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Sample records for relevant experimental parameters

  1. Measurements of relevant parameters in the formation of clathrate hydrates by a novel experimental apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Arca, S.; Di Profio, P.; Germani, R.; Savelli, G. [Perugia Univ., CEMIN, Perugia (Italy). Dept. of Chemistry

    2008-07-01

    There is a growing interest in understanding the thermodynamics and kinetics of clathrate hydrate formation. This paper presented a study that involved the design, construction, calibration, and testing of a new apparatus that could obtain as many parameters as possible in a single formation batch and that could measure unexplored clathrate hydrate parameters. The apparatus was capable of measuring equilibrium phases involving gaseous components. The paper described the conceptual design as well as the chamber, pressure line, temperature control, liquid addition line, and conductometric probe. The paper also discussed data acquisition, stirring, measurement examples, and internal illumination and video monitoring. It was concluded that refining measurements, particularly those concerning kinetic characterizations, is important in order to clarify several uncertain kinetic behaviors of clathrate hydrates. 6 refs., 16 figs.

  2. Experimental determination of mechanical parameters in sensorless ...

    Indian Academy of Sciences (India)

    V S S PAVAN KUMAR HARI

    pulse width modulation (PWM) selected. The three-phase .... and the simulation and experimental results are presented. ... between 0 and Ts due to the process of PWM. Hence, the .... MATLAB SIMULINK with the machine parameters in.

  3. Safe structural food bolus in elderly: the relevant parameters

    OpenAIRE

    Vandenberghe-Descamps, Mathilde; Septier, Chantal; Prot, Aurélie; Tournier, Carole; Hennequin, Martine; Vigneau, Evelyne; Feron, Gilles; Labouré, Hélène

    2017-01-01

    Mastication is essential to prepare food into a bolus ready to be swallowed safely, with no choking risk. Based on food bolus properties, a masticatory normative indicator was developed by Woda et al. (2010) to identify impaired masticatory function within good oral health population. The aim of the present study was to identify relevant parameters of bolus' structure to differentiate safe to unsafe bolus among elderly contrasting by their dental status.93 elderly, 58% with at least 7 posteri...

  4. Experimental evaluation of a modal parameter based system identification procedure

    Science.gov (United States)

    Yu, Minli; Feng, Ningsheng; Hahn, Eric J.

    2016-02-01

    Correct modelling of the foundation of a rotor bearing foundation system (RBFS) is an invaluable asset for the balancing and efficient running of turbomachinery. Numerical experiments have shown that a modal parameter based identification approach could be feasible for this purpose but there is a lack of experimental verification of the suitability of such a modal approach for even the simplest systems. In this paper the approach is tested on a simple experimental rig comprising a clamped horizontal bar with lumped masses. It is shown that apart from damping, the proposed approach can identify reasonably accurately the relevant modal parameters of the rig; and that the resulting equivalent system can predict reasonably well the frequency response of the rig. Hence, the proposed approach shows promise but further testing is required, since application to identifying the foundation of an RBFS involves the additional problem of accurately obtaining the force excitation from motion measurements.

  5. Simultaneous estimation of experimental and material parameters

    CSIR Research Space (South Africa)

    Jansen van Rensburg, GJ

    2012-07-01

    Full Text Available to the experimental data. An inverse analysis is performed that determines material properties and boundary conditions simultaneously. This idea is investigated using virtual experimental data. The virtual experimental data is obtained by performing a finite element...

  6. Electroconvulsive Therapy In Neuropsychiatry : Relevance Of Seizure Parameters

    Directory of Open Access Journals (Sweden)

    Gangadhar BN

    2000-01-01

    Full Text Available Electroconvulsive therapy (ECT is used to induce therapeutic seizures in various clinical conditions. It is specifically useful in depression, catatonia, patients with high suicidal risk, and those intolerant to drugs. Its beneficial effects surpass its side effects. Memory impairment is benign and transient. Its mechanism of action is unknown, though numerous neurotransmitters and neuroreceptors have been implicated. The standards of ECT practice are well established but still evolving in some particularly in unilateral ECT. Assessment of threshold by formula method may deliver higher stimulus dose compared with titration method. Cerebral seizure during ECT procedure is necessary. Motor (cuff method and EEG seizure monitoring are mandatory. Recent studies have shown some EEG parameters (amplitude, fractal dimension, symmetry, and post ictal suppression to be associated with therapeutic outcome. Besides seizure monitoring, measuring other physiological parameters such as heart rate (HR and blood pressure (BP may be useful indicators of therapeutic response. Use of ECT in neurological conditions as well as its application in psychiatric illnesses associated with neurological disorders has also been reviewed briefly.

  7. Method for extracting relevant electrical parameters from graphene field-effect transistors using a physical model

    International Nuclear Information System (INIS)

    Boscá, A.; Pedrós, J.; Martínez, J.; Calle, F.

    2015-01-01

    Due to its intrinsic high mobility, graphene has proved to be a suitable material for high-speed electronics, where graphene field-effect transistor (GFET) has shown excellent properties. In this work, we present a method for extracting relevant electrical parameters from GFET devices using a simple electrical characterization and a model fitting. With experimental data from the device output characteristics, the method allows to calculate parameters such as the mobility, the contact resistance, and the fixed charge. Differentiated electron and hole mobilities and direct connection with intrinsic material properties are some of the key aspects of this method. Moreover, the method output values can be correlated with several issues during key fabrication steps such as the graphene growth and transfer, the lithographic steps, or the metalization processes, providing a flexible tool for quality control in GFET fabrication, as well as a valuable feedback for improving the material-growth process

  8. Method for extracting relevant electrical parameters from graphene field-effect transistors using a physical model

    Energy Technology Data Exchange (ETDEWEB)

    Boscá, A., E-mail: alberto.bosca@upm.es [Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Dpto. de Ingeniería Electrónica, E.T.S.I. de Telecomunicación, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Pedrós, J. [Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Campus de Excelencia Internacional, Campus Moncloa UCM-UPM, Madrid 28040 (Spain); Martínez, J. [Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Dpto. de Ciencia de Materiales, E.T.S.I de Caminos, Canales y Puertos, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Calle, F. [Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Dpto. de Ingeniería Electrónica, E.T.S.I. de Telecomunicación, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Campus de Excelencia Internacional, Campus Moncloa UCM-UPM, Madrid 28040 (Spain)

    2015-01-28

    Due to its intrinsic high mobility, graphene has proved to be a suitable material for high-speed electronics, where graphene field-effect transistor (GFET) has shown excellent properties. In this work, we present a method for extracting relevant electrical parameters from GFET devices using a simple electrical characterization and a model fitting. With experimental data from the device output characteristics, the method allows to calculate parameters such as the mobility, the contact resistance, and the fixed charge. Differentiated electron and hole mobilities and direct connection with intrinsic material properties are some of the key aspects of this method. Moreover, the method output values can be correlated with several issues during key fabrication steps such as the graphene growth and transfer, the lithographic steps, or the metalization processes, providing a flexible tool for quality control in GFET fabrication, as well as a valuable feedback for improving the material-growth process.

  9. Experimental investigation of cutting parameters influence on ...

    Indian Academy of Sciences (India)

    429–445. c Indian Academy of Sciences ... This is employed for the manufacture of helicopter rotor blades and forging dies. ..... bij Xi X j +. ∑k i=1 bii X2 i ,. (2) where b0 is the free term of the regression equation, the .... Figure 1. Effect of cutting speed on surface roughness at various feed rates. ..... Experimental run order.

  10. Finding Relevant Parameters for the Thin-film Photovoltaic Cells Production Process with the Application of Data Mining Methods.

    Science.gov (United States)

    Ulaczyk, Jan; Morawiec, Krzysztof; Zabierowski, Paweł; Drobiazg, Tomasz; Barreau, Nicolas

    2017-09-01

    A data mining approach is proposed as a useful tool for the control parameters analysis of the 3-stage CIGSe photovoltaic cell production process, in order to find variables that are the most relevant for cell electric parameters and efficiency. The analysed data set consists of stage duration times, heater power values as well as temperatures for the element sources and the substrate - there are 14 variables per sample in total. The most relevant variables of the process have been found based on the so-called random forest analysis with the application of the Boruta algorithm. 118 CIGSe samples, prepared at Institut des Matériaux Jean Rouxel, were analysed. The results are close to experimental knowledge on the CIGSe cells production process. They bring new evidence to production parameters of new cells and further research. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. An experimental study on effect of process parameters in deep ...

    African Journals Online (AJOL)

    The effects of various deep drawing process parameters were determined by experimental study with the use of Taguchi fractional factorial design and analysis of variance for AA6111 Aluminum alloy. The optimum process parameters were determined based on their influence on the thickness variation at different regions ...

  12. Numerical and experimental investigation of geometric parameters in projection welding

    DEFF Research Database (Denmark)

    Kristensen, Lars; Zhang, Wenqi; Bay, Niels

    2000-01-01

    parameters by numerical modeling and experimental studies. SORPAS, an FEM program for numerical modeling of resistance welding, is developed as a tool to help in the phase of product design and process optimization in both spot and projection welding. A systematic experimental investigation of projection...... on the numerical and experimental investigations of the geometric parameters in projection welding, guidelines for selection of the geometry and material combinations in product design are proposed. These will be useful and applicable to industry.......Resistance projection welding is widely used for joining of workpieces with almost any geometric combination. This makes standardization of projection welding impossible. In order to facilitate industrial applications of projection welding, systematic investigations are carried out on the geometric...

  13. Using ANFIS for selection of more relevant parameters to predict dew point temperature

    International Nuclear Information System (INIS)

    Mohammadi, Kasra; Shamshirband, Shahaboddin; Petković, Dalibor; Yee, Por Lip; Mansor, Zulkefli

    2016-01-01

    Highlights: • ANFIS is used to select the most relevant variables for dew point temperature prediction. • Two cities from the central and south central parts of Iran are selected as case studies. • Influence of 5 parameters on dew point temperature is evaluated. • Appropriate selection of input variables has a notable effect on prediction. • Considering the most relevant combination of 2 parameters would be more suitable. - Abstract: In this research work, for the first time, the adaptive neuro fuzzy inference system (ANFIS) is employed to propose an approach for identifying the most significant parameters for prediction of daily dew point temperature (T_d_e_w). The ANFIS process for variable selection is implemented, which includes a number of ways to recognize the parameters offering favorable predictions. According to the physical factors influencing the dew formation, 8 variables of daily minimum, maximum and average air temperatures (T_m_i_n, T_m_a_x and T_a_v_g), relative humidity (R_h), atmospheric pressure (P), water vapor pressure (V_P), sunshine hour (n) and horizontal global solar radiation (H) are considered to investigate their effects on T_d_e_w. The used data include 7 years daily measured data of two Iranian cities located in the central and south central parts of the country. The results indicate that despite climate difference between the considered case studies, for both stations, V_P is the most influential variable while R_h is the least relevant element. Furthermore, the combination of T_m_i_n and V_P is recognized as the most influential set to predict T_d_e_w. The conducted examinations show that there is a remarkable difference between the errors achieved for most and less relevant input parameters, which highlights the importance of appropriate selection of input parameters. The use of more than two inputs may not be advisable and appropriate; thus, considering the most relevant combination of 2 parameters would be more suitable

  14. The estimation of effective doses using measurement of several relevant physical parameters from radon exposures

    International Nuclear Information System (INIS)

    Ridzikova, A; Fronka, A.; Maly, B.; Moucka, L.

    2003-01-01

    In the present investigation, we will be study the dose relevant factors from continual monitoring in real homes into account getting more accurate estimation of 222 Rn the effective dose. The dose relevant parameters include the radon concentration, the equilibrium factor (f), the fraction (fp) of unattached radon decay products and real time occupancy people in home. The result of the measurement are the time courses of radon concentration that are based on estimation effective doses together with assessment of the real time occupancy people indoor. We found out by analysis that year effective dose is lower than effective dose estimated by ICRP recommendation from the integral measurement that included only average radon concentration. Our analysis of estimation effective doses using measurement of several physical parameters was made only in one case and for the better specification is important to measure in different real occupancy houses. (authors)

  15. Safety analysis methodology with assessment of the impact of the prediction errors of relevant parameters

    International Nuclear Information System (INIS)

    Galia, A.V.

    2011-01-01

    The best estimate plus uncertainty approach (BEAU) requires the use of extensive resources and therefore it is usually applied for cases in which the available safety margin obtained with a conservative methodology can be questioned. Outside the BEAU methodology, there is not a clear approach on how to deal with the issue of considering the uncertainties resulting from prediction errors in the safety analyses performed for licensing submissions. However, the regulatory document RD-310 mentions that the analysis method shall account for uncertainties in the analysis data and models. A possible approach is presented, that is simple and reasonable, representing just the author's views, to take into account the impact of prediction errors and other uncertainties when performing safety analysis in line with regulatory requirements. The approach proposes taking into account the prediction error of relevant parameters. Relevant parameters would be those plant parameters that are surveyed and are used to initiate the action of a mitigating system or those that are representative of the most challenging phenomena for the integrity of a fission barrier. Examples of the application of the methodology are presented involving a comparison between the results with the new approach and a best estimate calculation during the blowdown phase for two small breaks in a generic CANDU 6 station. The calculations are performed with the CATHENA computer code. (author)

  16. Statistical approach for uncertainty quantification of experimental modal model parameters

    DEFF Research Database (Denmark)

    Luczak, M.; Peeters, B.; Kahsin, M.

    2014-01-01

    Composite materials are widely used in manufacture of aerospace and wind energy structural components. These load carrying structures are subjected to dynamic time-varying loading conditions. Robust structural dynamics identification procedure impose tight constraints on the quality of modal models...... represent different complexity levels ranging from coupon, through sub-component up to fully assembled aerospace and wind energy structural components made of composite materials. The proposed method is demonstrated on two application cases of a small and large wind turbine blade........ This paper aims at a systematic approach for uncertainty quantification of the parameters of the modal models estimated from experimentally obtained data. Statistical analysis of modal parameters is implemented to derive an assessment of the entire modal model uncertainty measure. Investigated structures...

  17. [Influence of reverse osmosis concentrate on physicochemical parameters of Sini decoction material system and their relevance].

    Science.gov (United States)

    Jin, Tang-Hui; Zhang, Liu-Hong; Zhu, Hua-Xu; Guo, Li-Wei; Li, Bo; Lu, Ming-Ming

    2014-04-01

    By studying the process of reverse osmosis system for traditional Chinese medicine materials physicochemical parameters affecting the osmotic pressure of its relevance, new compound system reverse osmosis process design methods were explored. Three concentrations materials for high, middle and low were dubbed with Sini decoction as a model drug, and pretreated by 50 thousand relative molecular weight cut-off ultrafiltration membrane. The viscosity, turbidity, conductivity, salinity, TDS, pH value and osmotic pressure of each sample were determined after the reverse osmosis to study the physical and chemical parameters between their respective correlations with the osmotic pressure, and characterized by HPLC chromatograms showing changes before and after the main chemical composition of samples of reverse osmosis. Conductivity-osmotic pressure, salinity-osmotic pressure of the linear correlation coefficient, TDS-osmotic pressure between the three sets of parameters were 0.963 8, 0.932 7, 0.973 7, respectively. Reverse osmosis concentrate and its characteristic spectrum ultrafiltrate HPLC similarity were up to 0. 968 or more, except the low concentrations. There is a significant correlation between the three physicochemical parameters (conductivity, salinity, TDS) and osmotic pressure of each sample system, and there is also significant linear correlation between salinity, conductivity, TDS. The original chemical composition of Sini decoction material concentrate was completely remained after the process of reverse osmosis.

  18. Investigation on gas medium parameters for an ArF excimer laser through orthogonal experimental design

    Science.gov (United States)

    Song, Xingliang; Sha, Pengfei; Fan, Yuanyuan; Jiang, R.; Zhao, Jiangshan; Zhou, Yi; Yang, Junhong; Xiong, Guangliang; Wang, Yu

    2018-02-01

    Due to complex kinetics of formation and loss mechanisms, such as ion-ion recombination reaction, neutral species harpoon reaction, excited state quenching and photon absorption, as well as their interactions, the performance behavior of different laser gas medium parameters for excimer laser varies greatly. Therefore, the effects of gas composition and total gas pressure on excimer laser performance attract continual research studies. In this work, orthogonal experimental design (OED) is used to investigate quantitative and qualitative correlations between output laser energy characteristics and gas medium parameters for an ArF excimer laser with plano-plano optical resonator operation. Optimized output laser energy with good pulse to pulse stability can be obtained effectively by proper selection of the gas medium parameters, which makes the most of the ArF excimer laser device. Simple and efficient method for gas medium optimization is proposed and demonstrated experimentally, which provides a global and systematic solution. By detailed statistical analysis, the significance sequence of relevant parameter factors and the optimized composition for gas medium parameters are obtained. Compared with conventional route of varying single gas parameter factor sequentially, this paper presents a more comprehensive way of considering multivariables simultaneously, which seems promising in striking an appropriate balance among various complicated parameters for power scaling study of an excimer laser.

  19. Creation of reliable relevance judgments in information retrieval systems evaluation experimentation through crowdsourcing: a review.

    Science.gov (United States)

    Samimi, Parnia; Ravana, Sri Devi

    2014-01-01

    Test collection is used to evaluate the information retrieval systems in laboratory-based evaluation experimentation. In a classic setting, generating relevance judgments involves human assessors and is a costly and time consuming task. Researchers and practitioners are still being challenged in performing reliable and low-cost evaluation of retrieval systems. Crowdsourcing as a novel method of data acquisition is broadly used in many research fields. It has been proven that crowdsourcing is an inexpensive and quick solution as well as a reliable alternative for creating relevance judgments. One of the crowdsourcing applications in IR is to judge relevancy of query document pair. In order to have a successful crowdsourcing experiment, the relevance judgment tasks should be designed precisely to emphasize quality control. This paper is intended to explore different factors that have an influence on the accuracy of relevance judgments accomplished by workers and how to intensify the reliability of judgments in crowdsourcing experiment.

  20. ANOVA parameters influence in LCF experimental data and simulation results

    Directory of Open Access Journals (Sweden)

    Vercelli A.

    2010-06-01

    Full Text Available The virtual design of components undergoing thermo mechanical fatigue (TMF and plastic strains is usually run in many phases. The numerical finite element method gives a useful instrument which becomes increasingly effective as the geometrical and numerical modelling gets more accurate. The constitutive model definition plays an important role in the effectiveness of the numerical simulation [1, 2] as, for example, shown in Figure 1. In this picture it is shown how a good cyclic plasticity constitutive model can simulate a cyclic load experiment. The component life estimation is the subsequent phase and it needs complex damage and life estimation models [3-5] which take into account of several parameters and phenomena contributing to damage and life duration. The calibration of these constitutive and damage models requires an accurate testing activity. In the present paper the main topic of the research activity is to investigate whether the parameters, which result to be influent in the experimental activity, influence the numerical simulations, thus defining the effectiveness of the models in taking into account of all the phenomena actually influencing the life of the component. To obtain this aim a procedure to tune the parameters needed to estimate the life of mechanical components undergoing TMF and plastic strains is presented for commercial steel. This procedure aims to be easy and to allow calibrating both material constitutive model (for the numerical structural simulation and the damage and life model (for life assessment. The procedure has been applied to specimens. The experimental activity has been developed on three sets of tests run at several temperatures: static tests, high cycle fatigue (HCF tests, low cycle fatigue (LCF tests. The numerical structural FEM simulations have been run on a commercial non linear solver, ABAQUS®6.8. The simulations replied the experimental tests. The stress, strain, thermal results from the thermo

  1. Outcome quality of in-patient cardiac rehabilitation in elderly patients--identification of relevant parameters.

    Science.gov (United States)

    Salzwedel, Annett; Nosper, Manfred; Röhrig, Bernd; Linck-Eleftheriadis, Sigrid; Strandt, Gert; Völler, Heinz

    2014-02-01

    Outcome quality management requires the consecutive registration of defined variables. The aim was to identify relevant parameters in order to objectively assess the in-patient rehabilitation outcome. From February 2009 to June 2010 1253 patients (70.9 ± 7.0 years, 78.1% men) at 12 rehabilitation clinics were enrolled. Items concerning sociodemographic data, the impairment group (surgery, conservative/interventional treatment), cardiovascular risk factors, structural and functional parameters and subjective health were tested in respect of their measurability, sensitivity to change and their propensity to be influenced by rehabilitation. The majority of patients (61.1%) were referred for rehabilitation after cardiac surgery, 38.9% after conservative or interventional treatment for an acute coronary syndrome. Functionally relevant comorbidities were seen in 49.2% (diabetes mellitus, stroke, peripheral artery disease, chronic obstructive lung disease). In three key areas 13 parameters were identified as being sensitive to change and subject to modification by rehabilitation: cardiovascular risk factors (blood pressure, low-density lipoprotein cholesterol, triglycerides), exercise capacity (resting heart rate, maximal exercise capacity, maximal walking distance, heart failure, angina pectoris) and subjective health (IRES-24 (indicators of rehabilitation status): pain, somatic health, psychological well-being and depression as well as anxiety on the Hospital Anxiety and Depression Scale). The outcome of in-patient rehabilitation in elderly patients can be comprehensively assessed by the identification of appropriate key areas, that is, cardiovascular risk factors, exercise capacity and subjective health. This may well serve as a benchmark for internal and external quality management.

  2. Parameter space of experimental chaotic circuits with high-precision control parameters

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Francisco F. G. de; Rubinger, Rero M. [Instituto de Física e Química, Universidade Federal de Itajubá, Itajubá, MG (Brazil); Sartorelli, José C., E-mail: sartorelli@if.usp.br [Universidade de São Paulo, São Paulo, SP (Brazil); Albuquerque, Holokx A. [Departamento de Física, Universidade do Estado de Santa Catarina, Joinville, SC (Brazil); Baptista, Murilo S. [Institute of Complex Systems and Mathematical Biology, SUPA, University of Aberdeen, Aberdeen (United Kingdom)

    2016-08-15

    We report high-resolution measurements that experimentally confirm a spiral cascade structure and a scaling relationship of shrimps in the Chua's circuit. Circuits constructed using this component allow for a comprehensive characterization of the circuit behaviors through high resolution parameter spaces. To illustrate the power of our technological development for the creation and the study of chaotic circuits, we constructed a Chua circuit and study its high resolution parameter space. The reliability and stability of the designed component allowed us to obtain data for long periods of time (∼21 weeks), a data set from which an accurate estimation of Lyapunov exponents for the circuit characterization was possible. Moreover, this data, rigorously characterized by the Lyapunov exponents, allows us to reassure experimentally that the shrimps, stable islands embedded in a domain of chaos in the parameter spaces, can be observed in the laboratory. Finally, we confirm that their sizes decay exponentially with the period of the attractor, a result expected to be found in maps of the quadratic family.

  3. The reaction between iodine and organic coatings under severe PWR accident conditions. An experimental parameter study

    Energy Technology Data Exchange (ETDEWEB)

    Hellmann, S; Funke, F; Greger, G U; Bleier, A; Morell, W [Siemens AG, Power Generation Group, Erlangen (Germany)

    1996-12-01

    An extensive experimental parameter study was performed on the deposition and on the resuspension kinetics in the reaction system iodine/organically coated surfaces. Both reactions in the gas phase and in the liquid phase were investigated and kinetic rate constants suitable for modelling were derived. Previous experimental studies on the reaction of iodine with organic coated surfaces were mostly limited to temperatures below 100{sup o}C. Thus, this parameter study aims at filling a gap and providing kinetic data on heterogeneous reactions with organic surfaces in the accident-relevant temperature range of 100-160{sup o}C. Two types of laboratory experiments carried out at Siemens/KWU using coatings representative for German power plants (epoxy-tape paint), namely gas phase tests and liquid phase tests. (author) 6 figs., 6 tabs., 5 refs.

  4. Optimization of Experimental Model Parameter Identification for Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Rosario Morello

    2013-09-01

    Full Text Available The smart grid approach is envisioned to take advantage of all available modern technologies in transforming the current power system to provide benefits to all stakeholders in the fields of efficient energy utilisation and of wide integration of renewable sources. Energy storage systems could help to solve some issues that stem from renewable energy usage in terms of stabilizing the intermittent energy production, power quality and power peak mitigation. With the integration of energy storage systems into the smart grids, their accurate modeling becomes a necessity, in order to gain robust real-time control on the network, in terms of stability and energy supply forecasting. In this framework, this paper proposes a procedure to identify the values of the battery model parameters in order to best fit experimental data and integrate it, along with models of energy sources and electrical loads, in a complete framework which represents a real time smart grid management system. The proposed method is based on a hybrid optimisation technique, which makes combined use of a stochastic and a deterministic algorithm, with low computational burden and can therefore be repeated over time in order to account for parameter variations due to the battery’s age and usage.

  5. Integrating retention soil filters into urban hydrologic models - Relevant processes and important parameters

    Science.gov (United States)

    Bachmann-Machnik, Anna; Meyer, Daniel; Waldhoff, Axel; Fuchs, Stephan; Dittmer, Ulrich

    2018-04-01

    Retention Soil Filters (RSFs), a form of vertical flow constructed wetlands specifically designed for combined sewer overflow (CSO) treatment, have proven to be an effective tool to mitigate negative impacts of CSOs on receiving water bodies. Long-term hydrologic simulations are used to predict the emissions from urban drainage systems during planning of stormwater management measures. So far no universally accepted model for RSF simulation exists. When simulating hydraulics and water quality in RSFs, an appropriate level of detail must be chosen for reasonable balancing between model complexity and model handling, considering the model input's level of uncertainty. The most crucial parameters determining the resultant uncertainties of the integrated sewer system and filter bed model were identified by evaluating a virtual drainage system with a Retention Soil Filter for CSO treatment. To determine reasonable parameter ranges for RSF simulations, data of 207 events from six full-scale RSF plants in Germany were analyzed. Data evaluation shows that even though different plants with varying loading and operation modes were examined, a simple model is sufficient to assess relevant suspended solids (SS), chemical oxygen demand (COD) and NH4 emissions from RSFs. Two conceptual RSF models with different degrees of complexity were assessed. These models were developed based on evaluation of data from full scale RSF plants and column experiments. Incorporated model processes are ammonium adsorption in the filter layer and degradation during subsequent dry weather period, filtration of SS and particulate COD (XCOD) to a constant background concentration and removal of solute COD (SCOD) by a constant removal rate during filter passage as well as sedimentation of SS and XCOD in the filter overflow. XCOD, SS and ammonium loads as well as ammonium concentration peaks are discharged primarily via RSF overflow not passing through the filter bed. Uncertainties of the integrated

  6. Parameter and state estimation of experimental chaotic systems using synchronization

    Science.gov (United States)

    Quinn, John C.; Bryant, Paul H.; Creveling, Daniel R.; Klein, Sallee R.; Abarbanel, Henry D. I.

    2009-07-01

    We examine the use of synchronization as a mechanism for extracting parameter and state information from experimental systems. We focus on important aspects of this problem that have received little attention previously and we explore them using experiments and simulations with the chaotic Colpitts oscillator as an example system. We explore the impact of model imperfection on the ability to extract valid information from an experimental system. We compare two optimization methods: an initial value method and a constrained method. Each of these involves coupling the model equations to the experimental data in order to regularize the chaotic motions on the synchronization manifold. We explore both time-dependent and time-independent coupling and discuss the use of periodic impulse coupling. We also examine both optimized and fixed (or manually adjusted) coupling. For the case of an optimized time-dependent coupling function u(t) we find a robust structure which includes sharp peaks and intervals where it is zero. This structure shows a strong correlation with the location in phase space and appears to depend on noise, imperfections of the model, and the Lyapunov direction vectors. For time-independent coupling we find the counterintuitive result that often the optimal rms error in fitting the model to the data initially increases with coupling strength. Comparison of this result with that obtained using simulated data may provide one measure of model imperfection. The constrained method with time-dependent coupling appears to have benefits in synchronizing long data sets with minimal impact, while the initial value method with time-independent coupling tends to be substantially faster, more flexible, and easier to use. We also describe a method of coupling which is useful for sparse experimental data sets. Our use of the Colpitts oscillator allows us to explore in detail the case of a system with one positive Lyapunov exponent. The methods we explored are easily

  7. Microwave generation for magnetic fusion energy applications: Task A -- Experimental and numerical study of microwave sources for ECRH incorporating depressed collectors and with ITER-relevant parameters, and Task B -- Theory and modeling of high frequency, high power gyrotron operation. Final report, July 15, 1994--July 14, 1995

    International Nuclear Information System (INIS)

    1995-01-01

    A proof-of-principle short pulse (∼ 100 ns) experiment has successfully demonstrated operation of a sheet-beam FEL amplifier with output power of 250 kW at 86 Ghz and with 24 dB saturated gain and ∼ 3% efficiency. Gain in the linear region was 30 dB. Measured performance parameters were in good agreement with predictions of a multi-mode, time dependence code. Also, a code has been developed to design depressed collectors which will enhance efficiency of ECRH sources (both FELs and gyrotrons). Extensive analytical and theoretical work in support of high power gyrotron development at Varian and MIT, and in support of ITER has been carried out. Specific studies are described. The effect of beam quality on the operation of the 145 GHz gyrotrons at MIT has been characterized using experimentally measured beam velocity distribution functions. The observed performance of these devices is consistent with a 10% RMS perpendicular velocity spread. An extensive study of mode competition in the 110 GHZ experiments at Varian and MIT has been carried out. Design criteria for the suppression of parasitic modes have been given for these experiments. The issues of mode competition and beam quality in the proposed 170 GHz megawatt gyrotrons for ITER have been investigated. Designs of cavities which eliminate unwanted modes have been made, and their sensitivity to beam quality studied. The constraints of lower power density and absence of mode competition coupled with the anticipated beam quality restrict efficiency. Efficiency can be improved by increasing the power density in the wall, improving beam quality, or perhaps by using a more advanced cavity. Studies of the causes of velocity spread in MIG guns have been initiated. Further, the effect of beam cavity misalignment on mode competition has been addressed

  8. Technical Note: Using experimentally determined proton spot scanning timing parameters to accurately model beam delivery time.

    Science.gov (United States)

    Shen, Jiajian; Tryggestad, Erik; Younkin, James E; Keole, Sameer R; Furutani, Keith M; Kang, Yixiu; Herman, Michael G; Bues, Martin

    2017-10-01

    To accurately model the beam delivery time (BDT) for a synchrotron-based proton spot scanning system using experimentally determined beam parameters. A model to simulate the proton spot delivery sequences was constructed, and BDT was calculated by summing times for layer switch, spot switch, and spot delivery. Test plans were designed to isolate and quantify the relevant beam parameters in the operation cycle of the proton beam therapy delivery system. These parameters included the layer switch time, magnet preparation and verification time, average beam scanning speeds in x- and y-directions, proton spill rate, and maximum charge and maximum extraction time for each spill. The experimentally determined parameters, as well as the nominal values initially provided by the vendor, served as inputs to the model to predict BDTs for 602 clinical proton beam deliveries. The calculated BDTs (T BDT ) were compared with the BDTs recorded in the treatment delivery log files (T Log ): ∆t = T Log -T BDT . The experimentally determined average layer switch time for all 97 energies was 1.91 s (ranging from 1.9 to 2.0 s for beam energies from 71.3 to 228.8 MeV), average magnet preparation and verification time was 1.93 ms, the average scanning speeds were 5.9 m/s in x-direction and 19.3 m/s in y-direction, the proton spill rate was 8.7 MU/s, and the maximum proton charge available for one acceleration is 2.0 ± 0.4 nC. Some of the measured parameters differed from the nominal values provided by the vendor. The calculated BDTs using experimentally determined parameters matched the recorded BDTs of 602 beam deliveries (∆t = -0.49 ± 1.44 s), which were significantly more accurate than BDTs calculated using nominal timing parameters (∆t = -7.48 ± 6.97 s). An accurate model for BDT prediction was achieved by using the experimentally determined proton beam therapy delivery parameters, which may be useful in modeling the interplay effect and patient throughput. The model may

  9. Some relevant parameters for assessing fire hazards of combustible mine materials using laboratory scale experiments.

    Science.gov (United States)

    Litton, Charles D; Perera, Inoka E; Harteis, Samuel P; Teacoach, Kara A; DeRosa, Maria I; Thomas, Richard A; Smith, Alex C

    2018-04-15

    When combustible materials ignite and burn, the potential for fire growth and flame spread represents an obvious hazard, but during these processes of ignition and flaming, other life hazards present themselves and should be included to ensure an effective overall analysis of the relevant fire hazards. In particular, the gases and smoke produced both during the smoldering stages of fires leading to ignition and during the advanced flaming stages of a developing fire serve to contaminate the surrounding atmosphere, potentially producing elevated levels of toxicity and high levels of smoke obscuration that render the environment untenable. In underground mines, these hazards may be exacerbated by the existing forced ventilation that can carry the gases and smoke to locations far-removed from the fire location. Clearly, materials that require high temperatures (above 1400 K) and that exhibit low mass loss during thermal decomposition, or that require high heat fluxes or heat transfer rates to ignite represent less of a hazard than materials that decompose at low temperatures or ignite at low levels of heat flux. In order to define and quantify some possible parameters that can be used to assess these hazards, small-scale laboratory experiments were conducted in a number of configurations to measure: 1) the toxic gases and smoke produced both during non-flaming and flaming combustion; 2) mass loss rates as a function of temperature to determine ease of thermal decomposition; and 3) mass loss rates and times to ignition as a function of incident heat flux. This paper describes the experiments that were conducted, their results, and the development of a set of parameters that could possibly be used to assess the overall fire hazard of combustible materials using small scale laboratory experiments.

  10. Experimental constraints on transport from dimensionless parameter scaling studies

    International Nuclear Information System (INIS)

    Petty, C.C.; Luce, T.C.; Baker, D.R.

    1998-02-01

    The scalings of heat transport with safety factor (q), normalized collisionality (v), plasma beta (β), and relative gyroradius (ρ*) have been measured on the DIII-D tokamak. The measured ρ* β and v scalings of heat transport indicate that E x B transport from drive wave turbulence is a plausible basis for anomalous transport. For high confinement (H) mode plasmas where the safety factor was varied at fixed magnetic shear, the effective (or one-fluid) thermal diffusivity was found to scale like χ eff ∝ q 2.3±0.64 , with the ion and electron fluids having the same q scaling to within the experimental errors except near the plasma edge. The scaling of the thermal confinement time with safety factor was in good agreement with this local transport dependence, τ th ∝ q -2.42±0.31 ; however, when the magnetic shear was allowed to vary to keep q 0 fixed during the (edge) safety factor scan, a weaker global dependence was observed, τ th ∝ q 95 -1.43±0.23 . This weaker dependence was mainly due to the change in the local value of q between the two types of scans. The combined ρ*, β, v and q scalings of heat transport for H-mode plasmas on DIII-D reproduce the empirical confinement scaling using physical (dimensionless) parameters with the exception of weaker power degradation

  11. Experimental constraints on transport from dimensionless parameter scaling studies

    International Nuclear Information System (INIS)

    Petty, C.C.; Luce, T.C.; Baker, D.R.; Ballet, B.; Carlstrom, T.N.; Cordey, J.G.; DeBoo, J.C.; Gohil, P.; Groebner, R.J.; Rice, B.W.; Thomas, D.M.; Wade, M.R.; Waltz, R.E.

    1998-01-01

    The scalings of heat transport with safety factor (q), normalized collisionality (ν), plasma beta (β), and relative gyroradius (ρ * ) have been measured on the DIII-D tokamak [Fusion Technol. 8, 441 (1985)]. The measured ρ * , β and ν scalings of heat transport indicate that ExB transport from drift wave turbulence is a plausible basis for anomalous transport. For high confinement (H) mode plasmas where the safety factor was varied at fixed magnetic shear, the effective (or one-fluid) thermal diffusivity was found to scale like χ eff ∝q 2.3±0.64 , with the ion and electron fluids having the same q scaling to within the experimental errors except near the plasma edge. The scaling of the thermal confinement time with safety factor was in good agreement with this local transport dependence, τ th ∝q -2.42±0.31 ; however, when the magnetic shear was allowed to vary to keep q 0 fixed during the (edge) safety factor scan, a weaker global dependence was observed, τ th ∝q 95 -1.43±0.23 . This weaker dependence was mainly due to the change in the local value of q between the two types of scans. The combined ρ * , β , ν and q scalings of heat transport for H-mode plasmas on DIII-D reproduce the empirical confinement scaling using physical (dimensional) parameters with the exception of weaker power degradation. copyright 1998 American Institute of Physics

  12. Experimental parameters research for oxides of synthesis by microwave

    Energy Technology Data Exchange (ETDEWEB)

    Ratmann, Ezequiel Cafumann; Moreira, Mário Lúcio; Ratmann, Cristiane Raubach; Cava, Sergio da Silva, E-mail: ezequiel.ratmann@gmail.com [Universidade Federal de Pelotas (UFPEL), RS (Brazil)

    2016-07-01

    Full text: The objective of this study is to investigate the influence of experimental parameter of zinc oxide (ZnO) in the structural and optical properties obtained by a microwave-assisted solvo thermal method. The method consists in obtaining ZnO at temperatures from 90 - 140 °C and subsequently characterized structurally and verify possible variations in optical characteristics through photoluminescence measurements. The characterizations were performed by X-ray diffraction, scanning electron microscopy and photoluminescence measurements. The results show that the change in temperature of synthesis does not affect the crystal structure of ZnO. The photoluminescence measurements show a shift only in the sample obtained at 120 °C temperature. A more detailed study on the 120°C system is necessary to be able to say that the effect observed in the optical property is due to the method of synthesis. References: [1] S. R. Pinnell, D. Fairhurst, R. Gillies, M. A. Mitchnick, and N. Kollias. Microfine zinc oxide is a superior sunscreen ingredient to microfine titanium dioxide, Dermatologic surgery, vol. 26, no. 4, pp. 309-314, 2000; [2] Efracio M. Flores. Influência do solvente nas propriedades estruturais e ópticas de sistema ZnO@ZnS core-shell, obtidos pelo método solvotérmico assistido por microondas. Dissertação de Mestrado. 2015. (author)

  13. Relevance and reliability of experimental data in human health risk assessment of pesticides.

    Science.gov (United States)

    Kaltenhäuser, Johanna; Kneuer, Carsten; Marx-Stoelting, Philip; Niemann, Lars; Schubert, Jens; Stein, Bernd; Solecki, Roland

    2017-08-01

    Evaluation of data relevance, reliability and contribution to uncertainty is crucial in regulatory health risk assessment if robust conclusions are to be drawn. Whether a specific study is used as key study, as additional information or not accepted depends in part on the criteria according to which its relevance and reliability are judged. In addition to GLP-compliant regulatory studies following OECD Test Guidelines, data from peer-reviewed scientific literature have to be evaluated in regulatory risk assessment of pesticide active substances. Publications should be taken into account if they are of acceptable relevance and reliability. Their contribution to the overall weight of evidence is influenced by factors including test organism, study design and statistical methods, as well as test item identification, documentation and reporting of results. Various reports make recommendations for improving the quality of risk assessments and different criteria catalogues have been published to support evaluation of data relevance and reliability. Their intention was to guide transparent decision making on the integration of the respective information into the regulatory process. This article describes an approach to assess the relevance and reliability of experimental data from guideline-compliant studies as well as from non-guideline studies published in the scientific literature in the specific context of uncertainty and risk assessment of pesticides. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Modelling of interplanetary pickup ion fluxes and relevance for LISM parameters

    International Nuclear Information System (INIS)

    Fahr, H.J.; Rucinski, D.

    1989-01-01

    It has been known for many years that neutral interstellar atoms enter the solar system from the upwind side and penetrate deep into the inner heliosphere. Helium atoms, in particular, advance towards very small solar distances before they are ionized and then again convected as He - pickup ions outwards with the solar wind. Since these ions were recently detected in space, we concentrate here on calculations of He + production rates and He + fluxes. It is shown that inside 1 a.u., the He - production is essentially determined both by solar e.u.v. photoionization and by electron impact ionization. We calculate He + production rates as a function of space coordinates, taking into account the core-halo structure of the energy distribution of solar wind electrons and their temperature distribution with distance according to relevant solar wind models. For this purpose, a newly developed program to compute He densities was used. In contrast to the production of H + , the He - production rates are found to be higher on the downwind axis than on the upwind axis by a factor of 5. We also determine partial and total He + ion fluxes as a function of solar distance and longitude. It is interesting to note that only the values for total fluxes agree well with the integrated He + fluxes measured by the SULEICA experiment aboard the AMPTE satellite. This indicates that pickup ions under the influence of the intrinsic MHD wave turbulence in the solar wind change their primary seed distribution function by rapid pitch-angle scattering and subsequent adiabatic cooling. To interpret the He + intensity profile along the orbit of the Earth in terms of LISM helium parameters, we point to the need to take into account carefully electron impact ionization in order to prevent misinterpretations. (author)

  15. Current Needs for the Experimental Investigation of the CHF Phenomenon Relevant to LWR Core Conditions

    International Nuclear Information System (INIS)

    Le Corre, J.M.

    2009-01-01

    The current achievements and needs toward the investigation, understanding and mechanistic prediction of the Critical Heat Flux (CHF) event, under PWR and BWR core conditions, are addressed in this paper. It is shown that, even when using advanced 3-D CFD simulation tools, the current approach to CHF mechanistic modeling has serious limitations. This is mainly due to the lack of information regarding the relevant two-phase flow pattern(s) (in particular near the heated wall) and associated mechanisms (at the meso and micro-scale) leading to the CHF event. Areas of current experimental needs are identified in order to address these shortcomings. In addition, the use of 1-D and 3-D numerical tools to mechanistically predict the CHF is discussed. It is shown that 3-D two-phase CFD codes may not be superior to 1-D codes without proper consideration of relevant constitutive relations. (author)

  16. Experimental Models of Vaginal Candidiasis and Their Relevance to Human Candidiasis

    Science.gov (United States)

    Sobel, Jack D.

    2016-01-01

    Vulvovaginal candidiasis (VVC) is a high-incidence disease seriously affecting the quality of life of women worldwide, particularly in its chronic, recurrent forms (RVVC), and with no definitive cure or preventive measure. Experimental studies in currently used rat and mouse models of vaginal candidiasis have generated a large mass of data on pathogenicity determinants and inflammation and immune responses of potential importance for the control of human pathology. However, reflection is necessary about the relevance of these rodent models to RVVC. Here we examine the chemical, biochemical, and biological factors that determine or contrast the forms of the disease in rodent models and in women and highlight the differences between them. We also appeal for approaches to improve or replace the current models in order to enhance their relevance to human infection. PMID:26883592

  17. Application of all relevant feature selection for failure analysis of parameter-induced simulation crashes in climate models

    Science.gov (United States)

    Paja, W.; Wrzesień, M.; Niemiec, R.; Rudnicki, W. R.

    2015-07-01

    The climate models are extremely complex pieces of software. They reflect best knowledge on physical components of the climate, nevertheless, they contain several parameters, which are too weakly constrained by observations, and can potentially lead to a crash of simulation. Recently a study by Lucas et al. (2013) has shown that machine learning methods can be used for predicting which combinations of parameters can lead to crash of simulation, and hence which processes described by these parameters need refined analyses. In the current study we reanalyse the dataset used in this research using different methodology. We confirm the main conclusion of the original study concerning suitability of machine learning for prediction of crashes. We show, that only three of the eight parameters indicated in the original study as relevant for prediction of the crash are indeed strongly relevant, three other are relevant but redundant, and two are not relevant at all. We also show that the variance due to split of data between training and validation sets has large influence both on accuracy of predictions and relative importance of variables, hence only cross-validated approach can deliver robust prediction of performance and relevance of variables.

  18. Application of all-relevant feature selection for the failure analysis of parameter-induced simulation crashes in climate models

    Science.gov (United States)

    Paja, Wiesław; Wrzesien, Mariusz; Niemiec, Rafał; Rudnicki, Witold R.

    2016-03-01

    Climate models are extremely complex pieces of software. They reflect the best knowledge on the physical components of the climate; nevertheless, they contain several parameters, which are too weakly constrained by observations, and can potentially lead to a simulation crashing. Recently a study by Lucas et al. (2013) has shown that machine learning methods can be used for predicting which combinations of parameters can lead to the simulation crashing and hence which processes described by these parameters need refined analyses. In the current study we reanalyse the data set used in this research using different methodology. We confirm the main conclusion of the original study concerning the suitability of machine learning for the prediction of crashes. We show that only three of the eight parameters indicated in the original study as relevant for prediction of the crash are indeed strongly relevant, three others are relevant but redundant and two are not relevant at all. We also show that the variance due to the split of data between training and validation sets has a large influence both on the accuracy of predictions and on the relative importance of variables; hence only a cross-validated approach can deliver a robust prediction of performance and relevance of variables.

  19. How to Select the most Relevant Roughness Parameters of a Surface: Methodology Research Strategy

    Science.gov (United States)

    Bobrovskij, I. N.

    2018-01-01

    In this paper, the foundations for new methodology creation which provides solving problem of surfaces structure new standards parameters huge amount conflicted with necessary actual floors quantity of surfaces structure parameters which is related to measurement complexity decreasing are considered. At the moment, there is no single assessment of the importance of a parameters. The approval of presented methodology for aerospace cluster components surfaces allows to create necessary foundation, to develop scientific estimation of surfaces texture parameters, to obtain material for investigators of chosen technological procedure. The methods necessary for further work, the creation of a fundamental reserve and development as a scientific direction for assessing the significance of microgeometry parameters are selected.

  20. A sEMG model with experimentally based simulation parameters.

    Science.gov (United States)

    Wheeler, Katherine A; Shimada, Hiroshima; Kumar, Dinesh K; Arjunan, Sridhar P

    2010-01-01

    A differential, time-invariant, surface electromyogram (sEMG) model has been implemented. While it is based on existing EMG models, the novelty of this implementation is that it assigns more accurate distributions of variables to create realistic motor unit (MU) characteristics. Variables such as muscle fibre conduction velocity, jitter (the change in the interpulse interval between subsequent action potential firings) and motor unit size have been considered to follow normal distributions about an experimentally obtained mean. In addition, motor unit firing frequencies have been considered to have non-linear and type based distributions that are in accordance with experimental results. Motor unit recruitment thresholds have been considered to be related to the MU type. The model has been used to simulate single channel differential sEMG signals from voluntary, isometric contractions of the biceps brachii muscle. The model has been experimentally verified by conducting experiments on three subjects. Comparison between simulated signals and experimental recordings shows that the Root Mean Square (RMS) increases linearly with force in both cases. The simulated signals also show similar values and rates of change of RMS to the experimental signals.

  1. Experimental evaluation of a quasi-modal parameter based rotor foundation identification technique

    Science.gov (United States)

    Yu, Minli; Liu, Jike; Feng, Ningsheng; Hahn, Eric J.

    2017-12-01

    Correct modelling of the foundation of rotating machinery is an invaluable asset in model-based rotor dynamic study. One attractive approach for such purpose is to identify the relevant modal parameters of an equivalent foundation using the motion measurements of rotor and foundation at the bearing supports. Previous research showed that, a complex quasi-modal parameter based system identification technique could be feasible for this purpose; however, the technique was only validated by identifying simple structures under harmonic excitation. In this paper, such identification technique is further extended and evaluated by identifying the foundation of a numerical rotor-bearing-foundation system and an experimental rotor rig respectively. In the identification of rotor foundation with multiple bearing supports, all application points of excitation forces transmitted through bearings need to be included; however the assumed vibration modes far outside the rotor operating speed cannot or not necessary to be identified. The extended identification technique allows one to identify correctly an equivalent foundation with fewer modes than the assumed number of degrees of freedom, essentially by generalising the technique to be able to handle rectangular complex modal matrices. The extended technique is robust in numerical and experimental validation and is therefore likely to be applicable in the field.

  2. Impact parameter determination in experimental analysis using neural network

    International Nuclear Information System (INIS)

    Haddad, F.; David, C.; Freslier, M.; Aichelin, J.; Haddad, F.; Hagel, K.; Li, J.; Mdeiwayeh, N.; Natowitz, J.B.; Wada, R.; Xiao, B.

    1997-01-01

    A neural network is used to determine the impact parameter in 40 Ca + 40 Ca reactions. The effect of the detection efficiency as well as the model dependence of the training procedure have been studied carefully. An overall improvement of the impact parameter determination of 25 % is obtained using this technique. The analysis of Amphora 40 Ca+ 40 Ca data at 35 MeV per nucleon using a neural network shows two well separated classes of events among the selected 'complete' events. (authors)

  3. Experimental Studies of the Transport Parameters of Warm Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Chouffani, Khalid [Idaho State Univ., Pocatello, ID (United States)

    2014-12-01

    There is a need to establish fundamental properties of matter and energy under extreme physical conditions. Although high energy density physics (HEDP) research spans a wide range of plasma conditions, there is one unifying regime that is of particular importance and complexity: that of warm dense matter, the transitional state between solid state condensed matter and energetic plasmas. Most laboratory experimental conditions, including inertial confinement implosion, fall into this regime. Because all aspects of laboratory-created high-energy-density plasmas transition through the warm dense matter regime, understanding the fundamental properties to determine how matter and energy interact in this regime is an important aspect of major research efforts in HEDP. Improved understanding of warm dense matter would have significant and wide-ranging impact on HEDP science, from helping to explain wire initiation studies on the Sandia Z machine to increasing the predictive power of inertial confinement fusion modeling. The central goal or objective of our proposed research is to experimentally determine the electrical resistivity, temperature, density, and average ionization state of a variety of materials in the warm dense matter regime, without the use of theoretical calculations. Since the lack of an accurate energy of state (EOS) model is primarily due to the lack of experimental data, we propose an experimental study of the transport coefficients of warm dense matter.

  4. Experimental and numerical investigation of plasma parameters in the magnetosheath

    Directory of Open Access Journals (Sweden)

    Dobreva Polya

    2018-01-01

    Full Text Available We investigate the behaviour of the plasma parameters in the magnetosheath in a case when Interball-1 satellite stayed in the magnetosheath, crossing the tail magnetopause. In our analysis we apply the numerical magnetosheath-magnetosphere model as a theoretical tool. The bow shock and the magnetopause are self-consistently determined in the process of the solution. The flow in the magnetosheath is governed by the Euler equations of compressible ideal gas. The magnetic field in the magnetosphere is calculated by a variant of the Tsyganenko model, modified to account for an asymmetric magnetopause. Also, the magnetopause currents in Tsyganenko model are replaced by numericaly calulated ones. Measurements from WIND spacecraft are used as a solar wind monitor. The results demonstrate a good agreement between the model-calculated and measured values of the parameters under investigation.

  5. Parameters for calculation of nuclear reactions of relevance to non-energy nuclear applications (Reference Input Parameter Library: Phase III). Summary report of the first research coordination meeting

    International Nuclear Information System (INIS)

    Capote Noy, R.

    2004-08-01

    A summary is given of the First Research Coordination Meeting on Parameters for Calculation of Nuclear Reactions of Relevance to Non-Energy Nuclear Applications (Reference Input Parameter Library: Phase III), including a critical review of the RIPL-2 file. The new library should serve as input for theoretical calculations of nuclear reaction data at incident energies up to 200 MeV, as needed for energy and non-energy modern applications of nuclear data. Technical discussions and the resulting work plan of the Coordinated Research Programme are summarized, along with actions and deadlines. Participants' contributions to the RCM are also attached. (author)

  6. Analysis of all dimensionful parameters relevant in gravitational dressing of conformal theories

    International Nuclear Information System (INIS)

    Dorn, H.; Otto, H.J.

    1992-01-01

    Starting from a covariant and background independent definition of normal ordered vertex operators we give an alternative derivation of the KPZ relation between conformal dimensions and their gravitational dressed partners. With our method we are able to study for arbitrary genus the dependence of N-point functions on all dimensionful parameters. Implications for the interpretation of gravitational dressed dimensions are discussed. (orig.)

  7. Experimental critical parameters of plutonium metal cylinders flooded with water

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    Forty-nine critical configurations are reported for experiments involving arrays of 3 kg plutonium metal cylinders moderated and reflected by water. Thirty-four of these describe systems assembled in the laboratory, while 15 others are derived critical parameters inferred from 46 subcritical cases. The arrays included 2x2xN, N = 2, 3, 4, and 5, in one program and 3x3x3 configurations in a later study. All were three-dimensional, nearly square arrays with equal horizontal lattice spacings but a different vertical lattice spacing. Horizontal spacings ranged from units in contact to 180 mm center-to-center; and vertical spacings ranged from about 80 mm to almost 400 mm center-to-center. Several nearly-equilateral 3x3x3 arrays exhibit an extremely sensitive dependence upon horizontal separation for identical vertical spacings. A line array of unreflected and essentially unmoderated canned plutonium metal units appeared to be well subcritical based on measurements made to assure safety during the manual assembly operations. All experiments were performed at two widely separated times in the mid-1970s and early 1980s under two programs at the Rocky Flats Plant`s Critical Mass Laboratory.

  8. Experimental critical parameters of plutonium metal cylinders flooded with water

    International Nuclear Information System (INIS)

    1996-07-01

    Forty-nine critical configurations are reported for experiments involving arrays of 3 kg plutonium metal cylinders moderated and reflected by water. Thirty-four of these describe systems assembled in the laboratory, while 15 others are derived critical parameters inferred from 46 subcritical cases. The arrays included 2x2xN, N = 2, 3, 4, and 5, in one program and 3x3x3 configurations in a later study. All were three-dimensional, nearly square arrays with equal horizontal lattice spacings but a different vertical lattice spacing. Horizontal spacings ranged from units in contact to 180 mm center-to-center; and vertical spacings ranged from about 80 mm to almost 400 mm center-to-center. Several nearly-equilateral 3x3x3 arrays exhibit an extremely sensitive dependence upon horizontal separation for identical vertical spacings. A line array of unreflected and essentially unmoderated canned plutonium metal units appeared to be well subcritical based on measurements made to assure safety during the manual assembly operations. All experiments were performed at two widely separated times in the mid-1970s and early 1980s under two programs at the Rocky Flats Plant's Critical Mass Laboratory

  9. Experimental setimeted of the some parameters of the conveyor belts

    Directory of Open Access Journals (Sweden)

    Marasová Daniela

    2001-12-01

    Full Text Available At present one of the most spread methods able to solve non-linear problems of the mechanics is theis the finite-element method. When solving problems of hyperelasticity by the finite-element method (FEM for introducing the input materials' constants of the body investigated, best - thought-out Money-Rivlin's theory is used. It is the method describing the behaviour of hyper-elastic materials with large elastic (reversible deformations. For the description of behaviour of the hyperelastic materials, can be used also the development from more members, comprising 5 or 9 materials' constants. The problem with the determining the hyperelastic materials' characteristics is one of the most important factors effecting the accuracy of the calculation result. The material's constants A and B are det-rmined experimentally from the practical tests, e.g.tensile, compressive or other and have to meet certain conditions. The paper shows the possibility how to determinate these matherials´ charakteris-tics and their verification by the mathematical model ANSYS.

  10. Status report [Parameters for calculation of nuclear reactions of relevance to non-energy nuclear applications

    International Nuclear Information System (INIS)

    Koning, A.

    2008-01-01

    Full text: Masses: Adopted Goriely HFB masses in TALYS as theoretical default instead of Moeller. Audi-Wapstra, Moeller and HFB masses tested formally with TALYS. Levels. Adopted latest discrete level update (2006) by Belgya (as sent by Capote) in TALYS. Tested with TALYS. Resonances. Adopted RIPL-2 D0 collection in TALYS. Tested by TALYS. Optical model. Coordinated Optical model segment for RIPL-3. Adopted Soukhovitskii CC potential as default for actinides. Covariances: Confirmed OMP parameter uncertainties from last meeting. Level density. Produced consistent set of level density parameters for CTM, BFM, GSM and HFM. Local models (per nucleus) and global models (systematics). With and without effective collective enhancement. Included and tested with TALYS Gamma-ray strength. Adopted Goriely HFB strength function tables as option (not default) in TALYS. Both formally tested and validated with TALYS. Fission. Adopted Sin-Capote WKB approximation in TALYS as option for fission calculations. Formally tested. RIPL-2/3 validation. Very extensive formal tests and validation procedures with TALYS. MONKEY code for random input files (has found RIPL errors in the past). Automatic comparison with all available EXFOR cross section data (for level density study). Started work on global parameter uncertainties (for covariances). SALTY nuclear data library (final version under construction): - 60 MeV n,g,p,d,t,h,a activation files for 1200 nuclides - 200 MeV n,g,p,d,t,h,a transport files for 250 nuclides RIPL is automatically being used by all TALYS users (and TALYS-related publications). TALYS-1.0 release in December 2007 (delay because of level densities). (author)

  11. Measuring reinforcement learning and motivation constructs in experimental animals: relevance to the negative symptoms of schizophrenia

    Science.gov (United States)

    Markou, Athina; Salamone, John D.; Bussey, Timothy; Mar, Adam; Brunner, Daniela; Gilmour, Gary; Balsam, Peter

    2013-01-01

    The present review article summarizes and expands upon the discussions that were initiated during a meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS; http://cntrics.ucdavis.edu). A major goal of the CNTRICS meeting was to identify experimental procedures and measures that can be used in laboratory animals to assess psychological constructs that are related to the psychopathology of schizophrenia. The issues discussed in this review reflect the deliberations of the Motivation Working Group of the CNTRICS meeting, which included most of the authors of this article as well as additional participants. After receiving task nominations from the general research community, this working group was asked to identify experimental procedures in laboratory animals that can assess aspects of reinforcement learning and motivation that may be relevant for research on the negative symptoms of schizophrenia, as well as other disorders characterized by deficits in reinforcement learning and motivation. The tasks described here that assess reinforcement learning are the Autoshaping Task, Probabilistic Reward Learning Tasks, and the Response Bias Probabilistic Reward Task. The tasks described here that assess motivation are Outcome Devaluation and Contingency Degradation Tasks and Effort-Based Tasks. In addition to describing such methods and procedures, the present article provides a working vocabulary for research and theory in this field, as well as an industry perspective about how such tasks may be used in drug discovery. It is hoped that this review can aid investigators who are conducting research in this complex area, promote translational studies by highlighting shared research goals and fostering a common vocabulary across basic and clinical fields, and facilitate the development of medications for the treatment of symptoms mediated by reinforcement learning and motivational deficits. PMID:23994273

  12. Measuring reinforcement learning and motivation constructs in experimental animals: relevance to the negative symptoms of schizophrenia.

    Science.gov (United States)

    Markou, Athina; Salamone, John D; Bussey, Timothy J; Mar, Adam C; Brunner, Daniela; Gilmour, Gary; Balsam, Peter

    2013-11-01

    The present review article summarizes and expands upon the discussions that were initiated during a meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS; http://cntrics.ucdavis.edu) meeting. A major goal of the CNTRICS meeting was to identify experimental procedures and measures that can be used in laboratory animals to assess psychological constructs that are related to the psychopathology of schizophrenia. The issues discussed in this review reflect the deliberations of the Motivation Working Group of the CNTRICS meeting, which included most of the authors of this article as well as additional participants. After receiving task nominations from the general research community, this working group was asked to identify experimental procedures in laboratory animals that can assess aspects of reinforcement learning and motivation that may be relevant for research on the negative symptoms of schizophrenia, as well as other disorders characterized by deficits in reinforcement learning and motivation. The tasks described here that assess reinforcement learning are the Autoshaping Task, Probabilistic Reward Learning Tasks, and the Response Bias Probabilistic Reward Task. The tasks described here that assess motivation are Outcome Devaluation and Contingency Degradation Tasks and Effort-Based Tasks. In addition to describing such methods and procedures, the present article provides a working vocabulary for research and theory in this field, as well as an industry perspective about how such tasks may be used in drug discovery. It is hoped that this review can aid investigators who are conducting research in this complex area, promote translational studies by highlighting shared research goals and fostering a common vocabulary across basic and clinical fields, and facilitate the development of medications for the treatment of symptoms mediated by reinforcement learning and motivational deficits. Copyright © 2013 Elsevier

  13. Atlas selection for hippocampus segmentation: Relevance evaluation of three meta-information parameters.

    Science.gov (United States)

    Dill, Vanderson; Klein, Pedro Costa; Franco, Alexandre Rosa; Pinho, Márcio Sarroglia

    2018-04-01

    Current state-of-the-art methods for whole and subfield hippocampus segmentation use pre-segmented templates, also known as atlases, in the pre-processing stages. Typically, the input image is registered to the template, which provides prior information for the segmentation process. Using a single standard atlas increases the difficulty in dealing with individuals who have a brain anatomy that is morphologically different from the atlas, especially in older brains. To increase the segmentation precision in these cases, without any manual intervention, multiple atlases can be used. However, registration to many templates leads to a high computational cost. Researchers have proposed to use an atlas pre-selection technique based on meta-information followed by the selection of an atlas based on image similarity. Unfortunately, this method also presents a high computational cost due to the image-similarity process. Thus, it is desirable to pre-select a smaller number of atlases as long as this does not impact on the segmentation quality. To pick out an atlas that provides the best registration, we evaluate the use of three meta-information parameters (medical condition, age range, and gender) to choose the atlas. In this work, 24 atlases were defined and each is based on the combination of the three meta-information parameters. These atlases were used to segment 352 vol from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Hippocampus segmentation with each of these atlases was evaluated and compared to reference segmentations of the hippocampus, which are available from ADNI. The use of atlas selection by meta-information led to a significant gain in the Dice similarity coefficient, which reached 0.68 ± 0.11, compared to 0.62 ± 0.12 when using only the standard MNI152 atlas. Statistical analysis showed that the three meta-information parameters provided a significant improvement in the segmentation accuracy. Copyright © 2018 Elsevier Ltd

  14. Correlation between mass transfer coefficient kLa and relevant operating parameters in cylindrical disposable shaken bioreactors on a bench-to-pilot scale.

    Science.gov (United States)

    Klöckner, Wolf; Gacem, Riad; Anderlei, Tibor; Raven, Nicole; Schillberg, Stefan; Lattermann, Clemens; Büchs, Jochen

    2013-12-02

    Among disposable bioreactor systems, cylindrical orbitally shaken bioreactors show important advantages. They provide a well-defined hydrodynamic flow combined with excellent mixing and oxygen transfer for mammalian and plant cell cultivations. Since there is no known universal correlation between the volumetric mass transfer coefficient for oxygen kLa and relevant operating parameters in such bioreactor systems, the aim of this current study is to experimentally determine a universal kLa correlation. A Respiration Activity Monitoring System (RAMOS) was used to measure kLa values in cylindrical disposable shaken bioreactors and Buckingham's π-Theorem was applied to define a dimensionless equation for kLa. In this way, a scale- and volume-independent kLa correlation was developed and validated in bioreactors with volumes from 2 L to 200 L. The final correlation was used to calculate cultivation parameters at different scales to allow a sufficient oxygen supply of tobacco BY-2 cell suspension cultures. The resulting equation can be universally applied to calculate the mass transfer coefficient for any of seven relevant cultivation parameters such as the reactor diameter, the shaking frequency, the filling volume, the viscosity, the oxygen diffusion coefficient, the gravitational acceleration or the shaking diameter within an accuracy range of +/- 30%. To our knowledge, this is the first kLa correlation that has been defined and validated for the cited bioreactor system on a bench-to-pilot scale.

  15. Inverse analyses of effective diffusion parameters relevant for a two-phase moisture model of cementitious materials

    DEFF Research Database (Denmark)

    Addassi, Mouadh; Johannesson, Björn; Wadsö, Lars

    2018-01-01

    Here we present an inverse analyses approach to determining the two-phase moisture transport properties relevant to concrete durability modeling. The purposed moisture transport model was based on a continuum approach with two truly separate equations for the liquid and gas phase being connected...... test, and, (iv) capillary suction test. Mass change over time, as obtained from the drying test, the two different cup test intervals and the capillary suction test, was used to obtain the effective diffusion parameters using the proposed inverse analyses approach. The moisture properties obtained...

  16. Experimental verification of different parameters influencing the fatigue S/N-curve

    International Nuclear Information System (INIS)

    Roos, E.; Maile, K.; Herter, K.-H.; Schuler, X.

    2005-01-01

    For the construction, design and operation of nuclear components the appropriate technical codes and standards provide detailed stress analysis procedures, material data and a design philosophy which guarantees a reliable behavior throughout the specified lifetime. Especially for cyclic stress evaluation the different codes and standards provide different fatigue analyses procedures to be performed considering the various (specified or measured) loading histories which are of mechanical and/or thermal origin and the geometric complexities of the components. In order to fully understand the background of the fatigue analysis included in the codes and standards as well as of the fatigue design curves used as a limiting criteria (to determine the fatigue life usage factor), it is important to understand the history, background as well as the methodologies which are important for the design engineers to get reliable results. The design rules according to the technical codes and standards provide for explicit consideration of cyclic operation, using design fatigue curves of allowable alternating loads (allowable stress or strain amplitudes) vs. number of loading cycles (S/N-curves), specific rules for assessing the cumulative fatigue damage (cumulative fatigue life usage factor) caused by different specified or monitored load cycles. The influence of different factors like welds, environment, surface finish, temperature, mean stress and size must be taken into consideration. In the paper parameters influencing the S/N-curves used within a fatigue analysis, like different type of material, the surface finish, the temperature, the difference between unwelded and welded areas, the strain rate as well as the influences of notches are verified on the basis of experimental results obtained by specimens testing in the LCF regime for high strain amplitudes. Thus safety margins relevant for the assessment of fatigue life depending on the different influencing parameters are

  17. On the design of experimental separation processes for maximum accuracy in the estimation of their parameters

    International Nuclear Information System (INIS)

    Volkman, Y.

    1980-07-01

    The optimal design of experimental separation processes for maximum accuracy in the estimation of process parameters is discussed. The sensitivity factor correlates the inaccuracy of the analytical methods with the inaccuracy of the estimation of the enrichment ratio. It is minimized according to the design parameters of the experiment and the characteristics of the analytical method

  18. An Experimental Study of the Local Parameters of a Damaged Cantilever

    DEFF Research Database (Denmark)

    Rytter, A.; Brincker, Rune; Kirkegaard, Poul Henning

    of results from experimental tests with six hollow section steel cantilevers containing a fatigue crack introduced from a narrow laser cut slot. The modal parameters have been identified for different size and location of a crack. The modal parameters have been estimated by mean of frequency domain and time...

  19. An Experimental Study of the Modal Parameters of a Damaged Cantilever

    DEFF Research Database (Denmark)

    Rytter, A.; Brincker, Rune; Kirkegaard, Poul Henning

    of results from experimental tests with six hollow section steel cantilevers containing a fatigue crack introduced from a narrow laser cut slot. The modal parameters have been identified for different size and location of a crack. The modal parameters have been estimated by mean of frequency domain and time...

  20. Repository environmental parameters and models/methodologies relevant to assessing the performance of high-level waste packages in basalt, tuff, and salt

    Energy Technology Data Exchange (ETDEWEB)

    Claiborne, H.C.; Croff, A.G.; Griess, J.C.; Smith, F.J.

    1987-09-01

    This document provides specifications for models/methodologies that could be employed in determining postclosure repository environmental parameters relevant to the performance of high-level waste packages for the Basalt Waste Isolation Project (BWIP) at Richland, Washington, the tuff at Yucca Mountain by the Nevada Test Site, and the bedded salt in Deaf Smith County, Texas. Guidance is provided on the identify of the relevant repository environmental parameters; the models/methodologies employed to determine the parameters, and the input data base for the models/methodologies. Supporting studies included are an analysis of potential waste package failure modes leading to identification of the relevant repository environmental parameters, an evaluation of the credible range of the repository environmental parameters, and a summary of the review of existing models/methodologies currently employed in determining repository environmental parameters relevant to waste package performance. 327 refs., 26 figs., 19 tabs.

  1. Repository environmental parameters and models/methodologies relevant to assessing the performance of high-level waste packages in basalt, tuff, and salt

    International Nuclear Information System (INIS)

    Claiborne, H.C.; Croff, A.G.; Griess, J.C.; Smith, F.J.

    1987-09-01

    This document provides specifications for models/methodologies that could be employed in determining postclosure repository environmental parameters relevant to the performance of high-level waste packages for the Basalt Waste Isolation Project (BWIP) at Richland, Washington, the tuff at Yucca Mountain by the Nevada Test Site, and the bedded salt in Deaf Smith County, Texas. Guidance is provided on the identify of the relevant repository environmental parameters; the models/methodologies employed to determine the parameters, and the input data base for the models/methodologies. Supporting studies included are an analysis of potential waste package failure modes leading to identification of the relevant repository environmental parameters, an evaluation of the credible range of the repository environmental parameters, and a summary of the review of existing models/methodologies currently employed in determining repository environmental parameters relevant to waste package performance. 327 refs., 26 figs., 19 tabs

  2. Radiometric parameters in freshwater samples of Centro Experimental Aramar (CTMSP/Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Marco Antonio P.V. [Laboratorio Radioecologico (LARE), Ipero, SP (Brazil). Dept. de Seguranca Nuclear; Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Experimental results are described obtained with gamma spectrometry, alpha and beta gross counts, liquid scintillation and fluorometry techniques for the measurement of background radiation in surface water samples, collected in Centro Experimental Aramar and surroundings, from 1988 to 2009. The estimated average background radiation concentrations in water samples in this region are low, related to the low level detection limits of the techniques, and indicates good water quality parameters, and low interference in the environment in Centro Experimental Aramar and region. (author)

  3. Theoretical and experimental determination of K - and L -shell x-ray relaxation parameters in Ni

    Science.gov (United States)

    Guerra, M.; Sampaio, J. M.; Parente, F.; Indelicato, P.; Hönicke, P.; Müller, M.; Beckhoff, B.; Marques, J. P.; Santos, J. P.

    2018-04-01

    Fluorescence yields (FY) for the Ni K and L shells were determined by a theoretical and an experimental group within the framework of the International Initiative on X-ray Fundamental Parameters (FPs) collaboration. Coster-Kronig (CK) parameters were also measured for the L shell of Ni. Theoretical calculations of the same parameters were performed using the Dirac-Fock method, including relativistic and QED corrections. The experimental values for the FY and CK were determined at the PTB laboratory in the synchrotron radiation facility BESSY II, Berlin, Germany, and are compared to the corresponding calculated values.

  4. Experimental and analytical determination of stability parameters for a balloon tethered in a wind

    Science.gov (United States)

    Redd, L. T.; Bennett, R. M.; Bland, S. R.

    1973-01-01

    Experimental and analytical techniques for determining stability parameters for a balloon tethered in a steady wind are described. These techniques are applied to a particular 7.64-meter-long balloon, and the results are presented. The stability parameters of interest appear as coefficients in linearized stability equations and are derived from the various forces and moments acting on the balloon. In several cases the results from the experimental and analytical techniques are compared and suggestions are given as to which techniques are the most practical means of determining values for the stability parameters.

  5. Characterization of an erbium doped fiber amplifier starting from its experimental parameters

    International Nuclear Information System (INIS)

    Bello J, M.; Kuzin, E.A.; Ibarra E, B.; Tellez G, R.

    2007-01-01

    In this paper we describe a method to characterize the gain of an erbium-doped fiber amplifier (EDFA) through the numerical simulation of the signal beam along the amplifier. The simulation is based on a model constituted by the propagation and rate equations for an erbium-doped fiber. The manipulation of these equations allows us to regroup the parameters present in an EDFA, which we have named the A, B, C, D parameters, and they can be obtained experimentally from an erbium-doped fiber. Experimental results show that the measurement of these parameters allow us to estimate with very good correspondence the amplifier gain. (Author)

  6. Monte Carlo calculations and experimental measurements of dosimetric parameters of the IRA-103Pd source

    International Nuclear Information System (INIS)

    Sadeghi, Mahdi; Hosseini, Hamed; Raisali, Gholamreza

    2008-01-01

    Full text: The use of 103 Pd seed sources for permanent prostate implantation has become a popular brachytherapy application. As recommended by AAPM the dosimetric characteristics of the new source must be determined using experimental and Monte Carlo simulations, before its use in clinical applications thus The goal of this report is the experimental and theoretical determination of the dosimetric characteristics of this source following the recommendations in the AAPM TG-43U1 protocol. Figure 1 shows the geometry of the IRA- 103 Pd source. The source consists of a cylindrical silver core, 0.3 cm long x 0.05 cm in diameter, onto which 0.5 nm layer of 103 Pd has been uniformly adsorbed. The effective active length of source is 0.3 cm and the silver core encapsulated inside a hollow titanium tube with 0.45 cm long, 0.07 cm and 0.08 inner and outer diameters and two caps. The Monte Carlo N-Particle (MCNP) code, version 4C, was used to determine the relevant dosimetric parameters of the source. The geometry of the Monte Carlo simulation performed in this study consisted of a sphere with 30 cm diameter. Dose distributions around this source were measured in two Perspex phantom using enough TLD chips. For these measurements, slabs of Perspex material were machined to accommodate the source and TLD chips. A value of 0.67± 1% cGy.h -1 .U -1 for, Λ, was calculated as the ratio of d(r 0 ,θ 0 ) and s K , that may be compared with Λ values obtained for 103 Pd sources. Result of calculations and measurements values of dosimetric parameters of the source including radial dose function, g(r), and anisotropy function, F(r,θ), has been shown in separate figures. The radial dose function, g(r), for the IRA- 103 Pd source and other 103 Pd sources is included in Fig. 2. Comparison between measured and Monte Carlo simulated dose function, g(r), and anisotropy function, F(r,θ), of this source demonstrated that they are in good agreement with each other and The value of Λ is

  7. Assessment of reduced-order unscented Kalman filter for parameter identification in 1-dimensional blood flow models using experimental data.

    Science.gov (United States)

    Caiazzo, A; Caforio, Federica; Montecinos, Gino; Muller, Lucas O; Blanco, Pablo J; Toro, Eluterio F

    2016-10-25

    This work presents a detailed investigation of a parameter estimation approach on the basis of the reduced-order unscented Kalman filter (ROUKF) in the context of 1-dimensional blood flow models. In particular, the main aims of this study are (1) to investigate the effects of using real measurements versus synthetic data for the estimation procedure (i.e., numerical results of the same in silico model, perturbed with noise) and (2) to identify potential difficulties and limitations of the approach in clinically realistic applications to assess the applicability of the filter to such setups. For these purposes, the present numerical study is based on a recently published in vitro model of the arterial network, for which experimental flow and pressure measurements are available at few selected locations. To mimic clinically relevant situations, we focus on the estimation of terminal resistances and arterial wall parameters related to vessel mechanics (Young's modulus and wall thickness) using few experimental observations (at most a single pressure or flow measurement per vessel). In all cases, we first perform a theoretical identifiability analysis on the basis of the generalized sensitivity function, comparing then the results owith the ROUKF, using either synthetic or experimental data, to results obtained using reference parameters and to available measurements. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Dietary supplementation of tiger nut alters biochemical parameters relevant to erectile function in l-NAME treated rats.

    Science.gov (United States)

    Olabiyi, Ayodeji A; Carvalho, Fabiano B; Bottari, Nathieli B; Lopes, Thauan F; da Costa, Pauline; Stefanelo, Naiara; Morsch, Vera M; Akindahunsi, Afolabi A; Oboh, Ganiyu; Schetinger, Maria Rosa

    2018-07-01

    Tiger nut tubers have been reportedly used for the treatment of erectile dysfunction (ED) in folk medicine without scientific basis. Hence, this study evaluated the effect of tiger nut on erectile dysfunction by assessing biochemical parameters relevant to ED in male rats by nitric oxide synthase (NOS) inhibitor, Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME) treatment. Rats were divided into five groups (n = 10) each: Control group; l-NAME plus basal diet; l-NAME plus Sildenafil citrate; diet supplemented processed tiger nut (20%) plus l-NAME;diet supplemented raw tiger nut (20%) plus l-NAME. l-NAME pre-treatment (40 mg/kg/day) lasted for 14 days. Arginase, acetycholinesterase (AChE) and adenosine deaminase (ADA) activities as well as nitric oxide levels (NO) in serum, brain and penile tissue were measured. l-NAME increased the activity of arginase, AChE and ADA and reduced NO levels. However, dietary supplementation with tiger nut caused a reduction on the activities of the above enzymes and up regulated nitric oxide levels when compared to the control group. The effect of tiger nut supplemented diet may be said to prevent alterations of the activities of the enzymes relevant in erectile function. Quercetin was revealed to be the most active component of tiger nut tuber by HPLC finger printing. Copyright © 2018. Published by Elsevier Ltd.

  9. Influence of several experimental parameters on As and Se leaching from coal fly ash samples

    International Nuclear Information System (INIS)

    Otero-Rey, Jose R.; Mato-Fernandez, Maria J.; Moreda-Pineiro, Jorge; Alonso-Rodriguez, Elia; Muniategui-Lorenzo, Soledad; Lopez-Mahia, Purificacion; Prada-Rodriguez, Dario

    2005-01-01

    Coal fly ash leaching process for As and Se is studied. Environmental parameters such as pH, temperature, solid-liquid ratio, particle size and leaching time are taken into account in order to simulate As and Se leaching process for disposal coal fly ash. Analysis of reference materials was carried out by using of hydride generation coupled to atomic fluorescence spectrometry. Plackett-Burman experimental design is used to know the significative parameters, and Box-Behnken experimental design is used to refine the results obtained for these significative parameters. pH and temperature shown a hardly influence in leaching process. Furthermore, leaching time was also significative. According our results, it may be assumed that percentage of As and Se leaching in experimental conditions tested is relatively low for acidic fly ashes

  10. Procedure for statistical analysis of one-parameter discrepant experimental data

    International Nuclear Information System (INIS)

    Badikov, Sergey A.; Chechev, Valery P.

    2012-01-01

    A new, Mandel–Paule-type procedure for statistical processing of one-parameter discrepant experimental data is described. The procedure enables one to estimate a contribution of unrecognized experimental errors into the total experimental uncertainty as well as to include it in analysis. A definition of discrepant experimental data for an arbitrary number of measurements is introduced as an accompanying result. In the case of negligible unrecognized experimental errors, the procedure simply reduces to the calculation of the weighted average and its internal uncertainty. The procedure was applied to the statistical analysis of half-life experimental data; Mean half-lives for 20 actinides were calculated and results were compared to the ENSDF and DDEP evaluations. On the whole, the calculated half-lives are consistent with the ENSDF and DDEP evaluations. However, the uncertainties calculated in this work essentially exceed the ENSDF and DDEP evaluations for discrepant experimental data. This effect can be explained by adequately taking into account unrecognized experimental errors. - Highlights: ► A new statistical procedure for processing one-parametric discrepant experimental data has been presented. ► Procedure estimates a contribution of unrecognized errors in the total experimental uncertainty. ► Procedure was applied for processing half-life discrepant experimental data. ► Results of the calculations are compared to the ENSDF and DDEP evaluations.

  11. Methodology to estimate parameters of an excitation system based on experimental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Saavedra-Montes, A.J. [Carrera 80 No 65-223, Bloque M8 oficina 113, Escuela de Mecatronica, Universidad Nacional de Colombia, Medellin (Colombia); Calle 13 No 100-00, Escuela de Ingenieria Electrica y Electronica, Universidad del Valle, Cali, Valle (Colombia); Ramirez-Scarpetta, J.M. [Calle 13 No 100-00, Escuela de Ingenieria Electrica y Electronica, Universidad del Valle, Cali, Valle (Colombia); Malik, O.P. [2500 University Drive N.W., Electrical and Computer Engineering Department, University of Calgary, Calgary, Alberta (Canada)

    2011-01-15

    A methodology to estimate the parameters of a potential-source controlled rectifier excitation system model is presented in this paper. The proposed parameter estimation methodology is based on the characteristics of the excitation system. A comparison of two pseudo random binary signals, two sampling periods for each one, and three estimation algorithms is also presented. Simulation results from an excitation control system model and experimental results from an excitation system of a power laboratory setup are obtained. To apply the proposed methodology, the excitation system parameters are identified at two different levels of the generator saturation curve. The results show that it is possible to estimate the parameters of the standard model of an excitation system, recording two signals and the system operating in closed loop with the generator. The normalized sum of squared error obtained with experimental data is below 10%, and with simulation data is below 5%. (author)

  12. A systematic study of distribution characters of infiltration parameters in an experimental basin by nuclear methods

    International Nuclear Information System (INIS)

    Gu Weizu; Lu Jieju; Lu Mingjiang; Chen Tingyang

    1988-01-01

    A case study of spatial variability of Philip's infiltration parameters was carried out in a small experimental catchment with an area of 0.8 ha by nuclear monitoring methods. Relationships between sorptivity S, parameter A and the average initial soil water content within 0.5 m depth of soil profiles over the catchment have been plotted. A watershed infiltration parameter distribution curve is set up and fitted approximately by f/F=1-(1-S/S M ) n . The parameters of composite infiltration response related to whole catchment are suggested. The author has studied it on an experimental basin by combined method of nuclear technology and micro-geomorphic analysis. The results are satisfactory. (author). 6 refs, 11 figs, 2 tabs

  13. Surgeon Reported Outcome Measure for Spine Trauma an International Expert Survey Identifying Parameters Relevant for The Outcome of Subaxial Cervical Spine Injuries

    NARCIS (Netherlands)

    Sadiqi, Said; Verlaan, Jorrit Jan; Lehr, A. M.; Dvorak, Marcel F.; Kandziora, Frank; Rajasekaran, S.; Schnake, Klaus J.; Vaccaro, Alexander R.; Oner, F. C.

    2016-01-01

    STUDY DESIGN.: International web-based survey OBJECTIVE.: To identify clinical and radiological parameters that spine surgeons consider most relevant when evaluating clinical and functional outcomes of subaxial cervical spine trauma patients. SUMMARY OF BACKGROUND DATA.: While an outcome instrument

  14. Discussion of the experimental methods of the estimation of the reaction impact parameter

    International Nuclear Information System (INIS)

    Muryn, B.; Dziunikowska, K.; Eskreys, A.; Coghen, T.

    1978-01-01

    Two methods of determination of the reaction impact parameter, the one proposed by Webber and other by Henyey and Pumplin, are compared and discussed. It is shown that the lower limits of the impact parameter bsub(L) obtained by means of these methods are comparable and are always very low (approximately < 0.5 fm). On the example of the Henyey - Pumplin method it is argued that the experimentally obtained values bsub(L) may be very unreliable estimates of the reaction impact parameter and that any comparison of different reactions or reactions channels may be meaningless. (author)

  15. Experimental investigation on dependency of interparticle distance in Coulomb crystal on various parameters

    OpenAIRE

    Adachi, Satoshi; Takayanagi, Masahiro; 足立 聡; 高柳 昌弘

    2007-01-01

    Dependency of interparticle distance in Coulomb crystal on various parameters such as plasma density, electron temperature, plasma potential and the Debye length are experimentally investigated. From the investigation, it is found that the interparticle distance is proportional to the Debye length.

  16. Experimental determination of lattice parameters for 2% enriched uranium heavy water reactor cores

    Energy Technology Data Exchange (ETDEWEB)

    Raisic, N; Takac, S; Markovic, H; Bosevski, T [Boris Kidric Institute of Nuclear Sciences Vinca, Belgrade (Yugoslavia)

    1963-04-15

    Systematic measurements of the buckling, infinite multiplication factor and the thermal utilization factor were made on a series of lattices for 2% enriched uranium tubular fuel elements in heavy water. This work represents the first phase of experimental verification of standard theoretical methods used for the determination of reactor parameters.

  17. Scale-up considerations relevant to experimental studies of nuclear waste-package behavior

    International Nuclear Information System (INIS)

    Coles, D.G.; Peters, R.D.

    1986-04-01

    Results from a study that investigated whether testing large-scale nuclear waste-package assemblages was technically warranted are reported. It was recognized that the majority of the investigations for predicting waste-package performance to date have relied primarily on laboratory-scale experimentation. However, methods for the successful extrapolation of the results from such experiments, both geometrically and over time, to actual repository conditions have not been well defined. Because a well-developed scaling technology exists in the chemical-engineering discipline, it was presupposed that much of this technology could be applicable to the prediction of waste-package performance. A review of existing literature documented numerous examples where a consideration of scaling technology was important. It was concluded that much of the existing scale-up technology is applicable to the prediction of waste-package performance for both size and time extrapolations and that conducting scale-up studies may be technically merited. However, the applicability for investigating the complex chemical interactions needs further development. It was recognized that the complexity of the system, and the long time periods involved, renders a completely theoretical approach to performance prediction almost hopeless. However, a theoretical and experimental study was defined for investigating heat and fluid flow. It was concluded that conducting scale-up modeling and experimentation for waste-package performance predictions is possible using existing technology. A sequential series of scaling studies, both theoretical and experimental, will be required to formulate size and time extrapolations of waste-package performance

  18. Theoretical and experimental studies relevant to interpretation of auroral emissions. Annual Report

    International Nuclear Information System (INIS)

    Keffer, C.E.

    1992-06-01

    The results obtained in the second year of a three year collaborative effort with MSFC are summarized. A succession of experimental studies was completed to determine the effects of the natural and induced space vehicle environment on the measurement of auroral images from space-based platforms. In addition, a global model which incorporates both auroral and dayglow emission sources is being developed to allow interpretation of measured auroral emissions. A description of work completed on these two tasks is presented

  19. The relevance of animal experimental results for the assessment of radiation genetic risks in man

    International Nuclear Information System (INIS)

    Stephan, G.

    1981-01-01

    No suitable data are available from man for the quantitative assessment of genetic radiation risk. Therefore, the results from experiments on animals must be utilized. Two hypotheses are presented here in drawing analogical conclusions from one species to another. Although the extrapolation of results from animal experiments remains an open question, the use of experimental results from mice seems to be justified for an assessment of the genetic radiation risk in man. (orig.) [de

  20. Time-Domain Simulations of Transient Species in Experimentally Relevant Environments

    Energy Technology Data Exchange (ETDEWEB)

    Ueltschi, Tyler W.; Fischer, Sean A.; Apra, Edoardo; Tarnovsky, Alexander N.; Govind, Niranjan; El-Khoury, Patrick Z.; Hess, Wayne P.

    2016-02-04

    Simulating the spectroscopic properties of short-lived thermal and photochemical reaction intermediates and products is a challenging task, as these species often feature atypical molecular and electronic structures. The complex environments in which such species typically reside in practice add further complexity to the problem. Herein, we tackle this problem in silico using ab initio molecular dynamics (AIMD) simulations, employing iso-CHBr3, namely H(Br)C-Br-Br, as a prototypical system. This species was chosen because it features both a non-conventional C-Br-Br bonding pattern, as well as a strong dependence of its spectral features on the local environment in which it resides, as illustrated in recent experimental reports. The spectroscopic properties of iso-CHBr3 were measured by several groups that captured this transient intermediate in the photochemistry of CHBr3 in the gas phase, in rare gas matrices at 5K, and in solution under ambient laboratory conditions. We simulate the UV-Vis and IR spectra of iso-CHBr3 in all three media, including a Ne cluster (64 atoms) and a methylcyclohexane cage (14 solvent molecules) representative of the matrix isolated and solvated species. We exclusively perform fully quantum mechanical static and dynamic simulations. By comparing our condensed phase simulations to their experimental analogues, we stress the importance of (i) conformational sampling, even at cryogenic temperatures, and (ii) using a fully quantum mechanical description of both solute and bath to properly account for the experimental observables.

  1. Improving the GIS-DRP Approach by Means of DelineatingRunoff Characteristics with New Discharge Relevant Parameters

    Directory of Open Access Journals (Sweden)

    Marco Hümann

    2013-01-01

    Full Text Available At present it is common to use geographic information system (GIS applications to assess runoff generation. One of these GIS-based tools to generate maps of dominant runoff processes is the so called GIS-DRP approach. The tool, which has been developed mainly based on agricultural areas, uses commonly available input data like a digital elevation model (DEM, geological information as well as land use information. The aim of this study is to test, validate and improve this GIS-DRP method for forested and silviculture areas. Hence, soil-hydrologic investigations and several mapping techniques of dominant runoff processes were conducted on 25 test-plots in four forested catchments in Rhineland-Palatinate (Germany and the Grand Duchy of Luxembourg. By comparing the results of the mapping techniques and those of the test plots, weak points in the original GIS-DRP method were detected. Subsequently, it was possible to enhance the GIS-DRP approach by incorporating new discharge relevant parameters like topsoil sealing, extreme weather events and semipermeability of the substratum. Moreover, the improved GIS-DRP approach can be widely used in different landscapes and for different fields of application. The adapted method can now support foresters and decision makers in forestry planning, answer questions concerning the landscape water balance and peripheral water retention or provide extra information for sustainable forest planning in times of a changing climate.

  2. Experimental Verification of Statistically Optimized Parameters for Low-Pressure Cold Spray Coating of Titanium

    Directory of Open Access Journals (Sweden)

    Damilola Isaac Adebiyi

    2016-06-01

    Full Text Available The cold spray coating process involves many process parameters which make the process very complex, and highly dependent and sensitive to small changes in these parameters. This results in a small operational window of the parameters. Consequently, mathematical optimization of the process parameters is key, not only to achieving deposition but also improving the coating quality. This study focuses on the mathematical identification and experimental justification of the optimum process parameters for cold spray coating of titanium alloy with silicon carbide (SiC. The continuity, momentum and the energy equations governing the flow through the low-pressure cold spray nozzle were solved by introducing a constitutive equation to close the system. This was used to calculate the critical velocity for the deposition of SiC. In order to determine the input temperature that yields the calculated velocity, the distribution of velocity, temperature, and pressure in the cold spray nozzle were analyzed, and the exit values were predicted using the meshing tool of Solidworks. Coatings fabricated using the optimized parameters and some non-optimized parameters are compared. The coating of the CFD-optimized parameters yielded lower porosity and higher hardness.

  3. Experimental Study of Plasma-Surface Interaction and Material Damage Relevant to ITER Type I Elms

    International Nuclear Information System (INIS)

    Makhlai, V.A.; Bandura, A.N.; Byrka, O.V. and others; Landman, I.; Neklyudov, I.M.

    2006-01-01

    The paper presents experimental investigations of main features of plasma surface interaction and energy transfer to the material surface in dependence on plasma heat loads. The experiments were performed with QSPA repetitive plasma pulses of the duration of 0.25 ms and the energy density up to 2.5 MJ/m 2 . Surface morphology of the targets exposed to QSPA plasma screams is analyzed. Relative contribution of the Lorentz force and plasma pressure gradient to the resulting surface profile is discussed. development of cracking on the tungsten surface and swelling of the surface are found to be in strong dependence on initial temperature of the target

  4. The GEKKO XII-HIPER (High Intensity Plasma Experimental Research) system relevant to ignition targets

    International Nuclear Information System (INIS)

    Miyanaga, N.; Nakatsuka, M.; Azechi, H.

    2001-01-01

    To test high gain targets surrogated in the planar geometry, we have constructed a new experimental system (HIPER) which provides the high ablation pressure with a uniform irradiance profile. These performances were achieved by bundling twelve beams of the existing GEKKO XII into a F/3 focus cone. The partially coherent light is introduced for the beam smoothing of a green foot pulse consisting of three beams, and the three-directional smoothing by spectral dispersion is utilized for residual nine beams delivering a blue main drive pulse. The detail of design concept and results of initial activation of this system are reported. (author)

  5. Fuel performance under normal PWR conditions: A review of relevant experimental results and models

    Science.gov (United States)

    Charles, M.; Lemaignan, C.

    1992-06-01

    Experiments conducted at Grenoble (CEA/DRN) over the past 20 years in the field of nuclear fuel behaviour are reviewed. Of particular concern is the need to achieve a comprehensive understanding of and subsequently overcome the limitations associated with high burnup and load-following conditions (pellet-cladding interaction (PCI), fission gas release (FGR), water-side corrosion). A general view is given of the organization of research work as well as some experimental details (irradiation, postirradiation examination — PIE). Based on various experimental programmes (Cyrano, Medicis, Anemone, Furet, Tango, Contact, Cansar, Hatac, Flog, Decor), the main contributions of the thermomechanical behaviour of a PWR fuel rod are described: thermal conductivity, in-pile densification, swelling, fission gas release in steady state and moderate transient conditions, gap thermal conductance, formation of primary and secondary ridges under PCI conditions. Specific programmes (Gdgrif, Thermox, Grimox) are devoted to the behaviour of particular fuels (gadolinia-bearing fuel, MOX fuel). Moreover, microstructure-based studies have been undertaken on fission gas release (fine analysis of the bubble population inside irradiated fuel samples), and on cladding behaviour (PCI related studies on stress-corrosion cracking (SCO, irradiation effects on zircaloy microstructure).

  6. Influence of experimental parameters on the microencapsulation of a photopolymerizable phase.

    Science.gov (United States)

    Pernot, J M; Brun, H; Pouyet, B; Sergent, M; Phan-Tan-Luu, R

    1993-01-01

    Conditions of microencapsulation by in situ polycondensation, using melamine-formaldehyde as wall material, are influenced by the chemical nature of the core to encapsulate. In our study concerning the encapsulation of a photopolymerizable phase containing an electrically charged compound, it was necessary to modify the experimental process to obtain capsules of good quality. We used the factorial design method of screening by utilization of an asymmetric matrix, according to the collapsing principle of Addleman. The advantage of this method is that it allows determination of the simultaneous influences of the 11 experimental parameters involved in this preparation. The calculation method can be applied to more than two levels for some of the factors. The continuously varying parameters were altered between two extreme levels, chosen to allow encapsulation. For discontinuous factors, such as the molecular weight of the modifying system or nature of the aminoplast, we used the commercially available compounds, respectively three and four kinds. The results of the obtained capsules were determined by comparing microphotographic pictures. With 16 experiments we found four more factors influencing quality of capsules. We also determined the most favourable levels for the other seven parameters. The results allowed us to find optimal conditions in the experimental field. We obtained capsules of a satisfactory quality for this purpose, using only minimum experimentation.

  7. The relevance of cytokines in the radiation-induced lung reaction. Experimental basis and clinical significance

    International Nuclear Information System (INIS)

    Ruebe, C.E.; Ruebe, C.; Rodemann, H.P.

    2004-01-01

    Methods: published data on radiation-induced cytokine expression from experimental and clinical studies are reviewed. Results and conclusion: the major pro-inflammatory cytokines in the radiation response of the lung include tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), and interleukin-6 (IL-6). Transforming growth factor-β (TGF-β) appears to be of particular importance in the development of lung fibrosis. First approaches with radioprotective agents and gene therapy to modify radiation-induced cytokine expression have been investigated for prevention of late effects of irradiation lung damage in animal experiments. Preliminary data of clinical studies suggest that elevated plasma TGF-β-levels during radiotherapy may predict the development of symptomatic radiation pneumonitis. The biological impacts of endogenous radiation-induced cytokine production by tumor cells in respect of tumor behavior, potential damage to normal tissue, and clinical status of the host still need to be determined more precisely. (orig.)

  8. An experimental and theoretical study of reaction steps relevant to the methanol-to-hydrocarbons reaction

    Energy Technology Data Exchange (ETDEWEB)

    Svelle, Stian

    2004-07-01

    The primary objective of the present work is to obtain new insight into the reaction mechanism of the zeolite catalyzed methanol-to-hydrocarbons (MTH) reaction. It was decided to use both experimental and computational techniques to reach this goal. An investigation of the n-butene + methanol system was therefore initiated. Over time, it became apparent that it was possible to determine the rate for the methylation of n-butene by methanol. The ethene and propene systems were therefore reexamined in order to collect kinetic information also for those cases. With the development of user-friendly quantum chemistry programs such as the Gaussian suite of programs, the possibility of applying quantum chemical methods to many types of problems has become readily available even for non-experts. When performing mechanistic studies, there is quite often a considerable synergy effect when combining experimental and computational approaches. The methylation reactions mentioned above turned out to be an issue well suited for quantum chemical investigations. The incentive for examining the halomethane reactivity was the clear analogy to the MTH reaction system. Alkene dimerization was also a reaction readily examined with quantum chemistry. As discussed in the introduction of this thesis, polymethylbenzenes, or their cationic counterparts, are suspected to be key intermediates in the MTH reaction. It was therefore decided to investigate the intrinsic reactivity of these species in the gas-phase by employing sophisticated mass spectrometric (MS) techniques in collaboration with the MS group at the Department of Chemistry, University of Oslo The data thus obtained will also be compared with results from an ongoing computational study on gas phase polymethylbenzenium reactivity. 6 papers presenting various studies are included. The titles are: 1) A Theoretical Investigation of the Methylation of Alkenes with Methanol over Acidic Zeolites. 2) A Theoretical Investigation of the

  9. An experimental and theoretical study of reaction steps relevant to the methanol-to-hydrocarbons reaction

    Energy Technology Data Exchange (ETDEWEB)

    Svelle, Stian

    2004-07-01

    The primary objective of the present work is to obtain new insight into the reaction mechanism of the zeolite catalyzed methanol-to-hydrocarbons (MTH) reaction. It was decided to use both experimental and computational techniques to reach this goal. An investigation of the n-butene + methanol system was therefore initiated. Over time, it became apparent that it was possible to determine the rate for the methylation of n-butene by methanol. The ethene and propene systems were therefore reexamined in order to collect kinetic information also for those cases. With the development of user-friendly quantum chemistry programs such as the Gaussian suite of programs, the possibility of applying quantum chemical methods to many types of problems has become readily available even for non-experts. When performing mechanistic studies, there is quite often a considerable synergy effect when combining experimental and computational approaches. The methylation reactions mentioned above turned out to be an issue well suited for quantum chemical investigations. The incentive for examining the halomethane reactivity was the clear analogy to the MTH reaction system. Alkene dimerization was also a reaction readily examined with quantum chemistry. As discussed in the introduction of this thesis, polymethylbenzenes, or their cationic counterparts, are suspected to be key intermediates in the MTH reaction. It was therefore decided to investigate the intrinsic reactivity of these species in the gas-phase by employing sophisticated mass spectrometric (MS) techniques in collaboration with the MS group at the Department of Chemistry, University of Oslo The data thus obtained will also be compared with results from an ongoing computational study on gas phase polymethylbenzenium reactivity. 6 papers presenting various studies are included. The titles are: 1) A Theoretical Investigation of the Methylation of Alkenes with Methanol over Acidic Zeolites. 2) A Theoretical Investigation of the

  10. Studies in nuclear structure relevant to Astrophysics: theoretical and experimental efforts

    International Nuclear Information System (INIS)

    Saha Sarkar, Maitreyee

    2016-01-01

    Experimental and theoretical investigations in the region around doubly magic neutron rich 132 Sn nucleus have recently revealed many intriguing issues concerning some newer aspects of nuclear structure in such exotic environments. These nuclei lie on or close to the path of the astrophysical r-process flow. A glimpse of the implication of these studies on the r-process nucleosynthesis will be discussed. Presently, the Nuclear Physics group in Saha Institute of Nuclear Physics is working for installation of a high-current, low energy Accelerator as the primary component of the Facility for Research in low Energy Nuclear Astrophysics (FRENA), a national facility, at Kolkata. Planning for future experiments has been undertaken for successful utilization of this facility. Implantation technique has been found to be one of the most effective methods to produce isotopically pure targets. We have prepared a few isotopically pure targets using this technique. Being the slowest process of the CNO cycle, study of the 14 N(p, γ) 15 O(Q = 7297 keV) capture reaction is of high astrophysical interest. From an experiment utilizing one of the newly prepared 14 N implanted targets, a preliminary estimate of the lifetime of 6792 keV state in 15 O has been obtained, using Doppler shift attenuation method (DSAM). The sensitivity of the results with respect to the uncertainties in various input quantities has been tested. This endeavour will be helpful to design a better experiment to extract more precise lifetime for this important state

  11. Experimental and theoretical data on ion-molecule-reactions relevant for plasma modelling

    International Nuclear Information System (INIS)

    Hansel, A.; Praxmarer, C.; Lindinger, W.

    1995-01-01

    Despite the fact that the rate coefficients of hundreds of ion-molecule-reactions have been published in the literature, much more data are required for the purpose of plasma modelling. Many ion molecule reactions have rate coefficients, k, as large as the collisional limiting value, k c , i.e. the rate coefficients k c at which ion-neutral collision complexes are formed are close to the actual rate coefficients observed. In the case of the interaction of an ion with a non polar molecule, k c , is determined by the Langevin limiting value k L being typically 10 -9 cm 3 s -1 . However, when ions react with polar molecules k c is predicted by the average dipole orientation (ADO) theory. These classical theories yield accurate rate coefficients at thermal and elevated temperatures for practically all proton transfer as well as for many charge transfer and hydrogen abstraction reactions. The agreement between experimental and calculated values is usually better than ±20% and in the case of proton transfer reactions the agreement seems to be even better as recent investigations have shown. Even the interaction of the permanent ion dipole with non polar and polar neutrals can be taken into account to predict reaction rate coefficients as has been shown very recently in reactions of the highly polar ion ArH 3 + with various neutrals

  12. Experimental kinetic parameters in the thermo-fluid-dynamic modelling of coal combustion

    International Nuclear Information System (INIS)

    Migliavacca, G.; Perini, M.; Parodi, E.

    2001-01-01

    The designing and the optimisation of modern and efficient combustion systems are nowadays frequently based on calculation tools for mathematical modelling, which are able to predict the evolution of the process starting from the first principles of physics. Otherwise, in many cases, specific experimental parameters are needed to describe the specific nature of the materials considered in the calculations. It is especially true in the modelling of coal combustion, which is a complex process strongly dependent on the chemical and physical features of the fuel. This paper describes some experimental techniques used to estimate the fundamental kinetic parameters of coal combustion and shows how this data may be introduced in a model calculation to predict the pollutant emissions from a real scale combustion plant [it

  13. EXPERIMENTAL DETERMINATION OF DOUBLE VIBE FUNCTION PARAMETERS IN DIESEL ENGINES WITH BIODIESEL

    Directory of Open Access Journals (Sweden)

    Radivoje B Pešić

    2010-01-01

    Full Text Available A zero-dimensional, one zone model of engine cycle for steady-state regimes of engines and a simplified procedure for indicator diagrams analysis have been developed at the Laboratory for internal combustion engines, fuels and lubricants of the Faculty of Mechanical Engineering in Kragujevac. In addition to experimental research, thermodynamic modeling of working process of diesel engine with direct injection has been presented in this paper. The simplified procedure for indicator diagrams analysis has been applied, also. The basic problem, a selection of shape parameters of double Vibe function used for modeling the engine operation process, has been solved. The influence of biodiesel fuel and engine working regimes on the start of combustion, combustion duration and shape parameter of double Vibe was determined by a least square fit of experimental heat release curve.

  14. A critical experimental study of integral physics parameters in simulated LMFBR meltdown cores

    International Nuclear Information System (INIS)

    Bhattacharyya, S.K.; Wade, D.C.; Bucher, R.G.; Smith, D.M.; McKnight, R.D.; Lesage, L.G.

    1978-01-01

    Integral physics parameters of several representative, idealized meltdown LMFBR configurations were measured in mockup critical assemblies on the ZPR-9 reactor at Argonne National Laboratory. The experiments were designed to provide data for the validation of analytical methods used in the neutronics part of LMFBR accident analysis. Large core distortions were introduced in these experiments (involving 18.5% core volume) and the reactivity worths of configuration changes were determined. The neutronics parameters measured in the various configurations showed large changes upon core distortion. Both diffusion theory and transport theory methods were shown to mispredict the experimental configuration eigenvalues. In addition, diffusion theory methods were shown to result in a non-conservative misprediction of the experimental configuration change worths. (author)

  15. Experimental estimations of the kinetics parameters of the IBR-2M reactor by stochastic noises

    International Nuclear Information System (INIS)

    Pepelyshev, Yu.N.; Tajybov, L.A.; Garibov, A.A.; Mekhtieva, R.N.

    2012-01-01

    Experimental investigations of stochastic fluctuations of pulse energy of the IBR-2M reactor have been carried out which allowed us to obtain some of the parameters of the reactor kinetics. At different levels of average power a sequence of values of pulse energy was recorded with the calculation of the distribution parameters. An ionization chamber with boron installed near the active zone was used as a neutron detector. The research results allowed us to estimate the average lifetime of prompt neutrons τ = (6.53±0.2)·10 -8 s, absolute power of the reactor and intensity of the source of spontaneous neutrons S sp ≤(6.72±0.12)·10 6 s -1 . It was shown that the experimental results are close to the calculated ones

  16. Early-Life Effects on Adult Physical Activity: Concepts, Relevance, and Experimental Approaches.

    Science.gov (United States)

    Garland, Theodore; Cadney, Marcell D; Waterland, Robert A

    Locomotion is a defining characteristic of animal life and plays a crucial role in most behaviors. Locomotion involves physical activity, which can have far-reaching effects on physiology and neurobiology, both acutely and chronically. In human populations and in laboratory rodents, higher levels of physical activity are generally associated with positive health outcomes, although excessive exercise can have adverse consequences. Whether and how such relationships occur in wild animals is unknown. Behavioral variation among individuals arises from genetic and environmental factors and their interactions as well as from developmental programming (persistent effects of early-life environment). Although tremendous progress has been made in identifying genetic and environmental influences on individual differences in behavior, early-life effects are not well understood. Early-life effects can in some cases persist across multiple generations following a single exposure and, in principle, may constrain or facilitate the rate of evolution at multiple levels of biological organization. Understanding the mechanisms of such transgenerational effects (e.g., exposure to stress hormones in utero, inherited epigenetic alterations) may prove crucial to explaining unexpected and/or sex-specific responses to selection as well as limits to adaptation. One area receiving increased attention is early-life effects on adult physical activity. Correlational data from epidemiological studies suggest that early-life nutritional stress can (adversely) affect adult human activity levels and associated physiological traits (e.g., body composition, metabolic health). The few existing studies of laboratory rodents demonstrate that both maternal and early-life exercise can affect adult levels of physical activity and related phenotypes. Going forward, rodents offer many opportunities for experimental studies of (multigenerational) early-life effects, including studies that use maternal

  17. Experimental Methodology for Determining Optimum Process Parameters for Production of Hydrous Metal Oxides by Internal Gelation

    Energy Technology Data Exchange (ETDEWEB)

    Collins, J.L.

    2005-10-28

    The objective of this report is to describe a simple but very useful experimental methodology that was used to determine optimum process parameters for preparing several hydrous metal-oxide gel spheres by the internal gelation process. The method is inexpensive and very effective in collection of key gel-forming data that are needed to prepare the hydrous metal-oxide microspheres of the best quality for a number of elements.

  18. Experimental determination and verification of the parameters used in a proton pencil beam algorithm

    International Nuclear Information System (INIS)

    Szymanowski, H.; Mazal, A.; Nauraye, C.; Biensan, S.; Ferrand, R.; Murillo, M.C.; Caneva, S.; Gaboriaud, G.; Rosenwald, J.C.

    2001-01-01

    We present an experimental procedure for the determination and the verification under practical conditions of physical and computational parameters used in our proton pencil beam algorithm. The calculation of the dose delivered by a single pencil beam relies on a measured spread-out Bragg peak, and the description of its radial spread at depth features simple specific parameters accounting individually for the influence of the beam line as a whole, the beam energy modulation, the compensator, and the patient medium. For determining the experimental values of the physical parameters related to proton scattering, we utilized a simple relation between Gaussian radial spreads and the width of lateral penumbras. The contribution from the beam line has been extracted from lateral penumbra measurements in air: a linear variation with the distance collimator-point has been observed. Analytically predicted radial spreads within the patient were in good agreement with experimental values in water under various reference conditions. Results indicated no significant influence of the beam energy modulation. Using measurements in presence of Plexiglas slabs, a simple assumption on the effective source of scattering due to the compensator has been stated, leading to accurate radial spread calculations. Dose measurements in presence of complexly shaped compensators have been used to assess the performances of the algorithm supplied with the adequate physical parameters. One of these compensators has also been used, together with a reference configuration, for investigating a set of computational parameters decreasing the calculation time while maintaining a high level of accuracy. Faster dose computations have been performed for algorithm evaluation in the presence of geometrical and patient compensators, and have shown good agreement with the measured dose distributions

  19. Experimental determination of chosen document elements parameters from raster graphics sources

    Directory of Open Access Journals (Sweden)

    Jiří Rybička

    2010-01-01

    Full Text Available Visual appearance of documents and their formal quality is considered to be as important as the content quality. Formal and typographical quality of documents can be evaluated by an automated system that processes raster images of documents. A document is described by a formal model that treats a page as an object and also as a set of elements, whereas page elements include text and graphic object. All elements are described by their parameters depending on elements’ type. For future evaluation, mainly text objects are important. This paper describes the experimental determination of chosen document elements parameters from raster images. Techniques for image processing are used, where an image is represented as a matrix of dots and parameter values are extracted. Algorithms for parameter extraction from raster images were designed and were aimed mainly at typographical parameters like indentation, alignment, font size or spacing. Algorithms were tested on a set of 100 images of paragraphs or pages and provide very good results. Extracted parameters can be directly used for typographical quality evaluation.

  20. Impact parameter sensitive study of inner-shell atomic processes in the experimental storage ring

    Science.gov (United States)

    Gumberidze, A.; Kozhuharov, C.; Zhang, R. T.; Trotsenko, S.; Kozhedub, Y. S.; DuBois, R. D.; Beyer, H. F.; Blumenhagen, K.-H.; Brandau, C.; Bräuning-Demian, A.; Chen, W.; Forstner, O.; Gao, B.; Gassner, T.; Grisenti, R. E.; Hagmann, S.; Hillenbrand, P.-M.; Indelicato, P.; Kumar, A.; Lestinsky, M.; Litvinov, Yu. A.; Petridis, N.; Schury, D.; Spillmann, U.; Trageser, C.; Trassinelli, M.; Tu, X.; Stöhlker, Th.

    2017-10-01

    In this work, we present a pilot experiment in the experimental storage ring (ESR) at GSI devoted to impact parameter sensitive studies of inner shell atomic processes for low-energy (heavy-) ion-atom collisions. The experiment was performed with bare and He-like xenon ions (Xe54+, Xe52+) colliding with neutral xenon gas atoms, resulting in a symmetric collision system. This choice of the projectile charge states was made in order to compare the effect of a filled K-shell with the empty one. The projectile and target X-rays have been measured at different observation angles for all impact parameters as well as for the impact parameter range of ∼35-70 fm.

  1. An experimental study of symmetric and asymmetric peak-fitting parameters for alpha-particle spectrometry

    International Nuclear Information System (INIS)

    Martin Sanchez, A.; Vera Tome, F.; Caceres Marzal, D.; Bland, C.J.

    1994-01-01

    A pulse-height spectrum of alpha-particle emissions at discrete energies can be fitted by the peak-shape functions generated by combining asymmetric truncated exponential functions with a symmetric Gaussian distribution. These functions have been applied successfully by several workers. A correlation was previously found between the variance of the symmetric Gaussian portion of the fitting function, and the parameter characterising the principal exponential tailing function. The results of a more detailed experimental study are reported, which involve varying the angle and the distance between the source and the detector. This analysis shows that the parameters of the symmetric and asymmetric parts of the fitted functions seem to depend on either the detector or the source. These parameters are influenced by the energy loss suffered by the alpha-particles as well as by the efficiency of charge collection in the solid-state detector. (orig.)

  2. Inference of missing data and chemical model parameters using experimental statistics

    Science.gov (United States)

    Casey, Tiernan; Najm, Habib

    2017-11-01

    A method for determining the joint parameter density of Arrhenius rate expressions through the inference of missing experimental data is presented. This approach proposes noisy hypothetical data sets from target experiments and accepts those which agree with the reported statistics, in the form of nominal parameter values and their associated uncertainties. The data exploration procedure is formalized using Bayesian inference, employing maximum entropy and approximate Bayesian computation methods to arrive at a joint density on data and parameters. The method is demonstrated in the context of reactions in the H2-O2 system for predictive modeling of combustion systems of interest. Work supported by the US DOE BES CSGB. Sandia National Labs is a multimission lab managed and operated by Nat. Technology and Eng'g Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell Intl, for the US DOE NCSA under contract DE-NA-0003525.

  3. Experimental studies of parameters affecting the heat generation in friction stir welding process

    Directory of Open Access Journals (Sweden)

    Mijajlović Miroslav M.

    2012-01-01

    Full Text Available Heat generation is a complex process of transformation of a specific type of energy into heat. During friction stir welding, one part of mechanical energy delivered to the welding tool is consumed in the welding process, another is used for deformational processes etc., and the rest of the energy is transformed into heat. The analytical procedure for the estimation of heat generated during friction stir welding is very complex because it includes a significant number of variables and parameters, and many of them cannot be fully mathematically explained. Because of that, the analytical model for the estimation of heat generated during friction stir welding defines variables and parameters that dominantly affect heat generation. These parameters are numerous and some of them, e. g. loads, friction coefficient, torque, temperature, are estimated experimentally. Due to the complex geometry of the friction stir welding process and requirements of the measuring equipment, adequate measuring configurations and specific constructional solutions that provide adequate measuring positions are necessary. This paper gives an overview of the process of heat generation during friction stir welding, the most influencing parameters on heat generation, constructional solutions for the measuring equipment needed for these experimental researches and examples of measured values.

  4. Experimental design for estimating parameters of rate-limited mass transfer: Analysis of stream tracer studies

    Science.gov (United States)

    Wagner, Brian J.; Harvey, Judson W.

    1997-01-01

    Tracer experiments are valuable tools for analyzing the transport characteristics of streams and their interactions with shallow groundwater. The focus of this work is the design of tracer studies in high-gradient stream systems subject to advection, dispersion, groundwater inflow, and exchange between the active channel and zones in surface or subsurface water where flow is stagnant or slow moving. We present a methodology for (1) evaluating and comparing alternative stream tracer experiment designs and (2) identifying those combinations of stream transport properties that pose limitations to parameter estimation and therefore a challenge to tracer test design. The methodology uses the concept of global parameter uncertainty analysis, which couples solute transport simulation with parameter uncertainty analysis in a Monte Carlo framework. Two general conclusions resulted from this work. First, the solute injection and sampling strategy has an important effect on the reliability of transport parameter estimates. We found that constant injection with sampling through concentration rise, plateau, and fall provided considerably more reliable parameter estimates than a pulse injection across the spectrum of transport scenarios likely encountered in high-gradient streams. Second, for a given tracer test design, the uncertainties in mass transfer and storage-zone parameter estimates are strongly dependent on the experimental Damkohler number, DaI, which is a dimensionless combination of the rates of exchange between the stream and storage zones, the stream-water velocity, and the stream reach length of the experiment. Parameter uncertainties are lowest at DaI values on the order of 1.0. When DaI values are much less than 1.0 (owing to high velocity, long exchange timescale, and/or short reach length), parameter uncertainties are high because only a small amount of tracer interacts with storage zones in the reach. For the opposite conditions (DaI ≫ 1.0), solute

  5. Propagation of a channelized debris-flow: experimental investigation and parameters identification for numerical modelling

    Science.gov (United States)

    Termini, Donatella

    2013-04-01

    Recent catastrophic events due to intense rainfalls have mobilized large amount of sediments causing extensive damages in vast areas. These events have highlighted how debris-flows runout estimations are of crucial importance to delineate the potentially hazardous areas and to make reliable assessment of the level of risk of the territory. Especially in recent years, several researches have been conducted in order to define predicitive models. But, existing runout estimation methods need input parameters that can be difficult to estimate. Recent experimental researches have also allowed the assessment of the physics of the debris flows. But, the major part of the experimental studies analyze the basic kinematic conditions which determine the phenomenon evolution. Experimental program has been recently conducted at the Hydraulic laboratory of the Department of Civil, Environmental, Aerospatial and of Materials (DICAM) - University of Palermo (Italy). The experiments, carried out in a laboratory flume appositely constructed, were planned in order to evaluate the influence of different geometrical parameters (such as the slope and the geometrical characteristics of the confluences to the main channel) on the propagation phenomenon of the debris flow and its deposition. Thus, the aim of the present work is to give a contribution to defining input parameters in runout estimation by numerical modeling. The propagation phenomenon is analyzed for different concentrations of solid materials. Particular attention is devoted to the identification of the stopping distance of the debris flow and of the involved parameters (volume, angle of depositions, type of material) in the empirical predictive equations available in literature (Rickenmanm, 1999; Bethurst et al. 1997). Bethurst J.C., Burton A., Ward T.J. 1997. Debris flow run-out and landslide sediment delivery model tests. Journal of hydraulic Engineering, ASCE, 123(5), 419-429 Rickenmann D. 1999. Empirical relationships

  6. Vegetation growth parameters and leaf temperature: Experimental results from a six plots green roofs' system

    International Nuclear Information System (INIS)

    Ferrante, Patrizia; La Gennusa, Maria; Peri, Giorgia; Rizzo, Gianfranco; Scaccianoce, Gianluca

    2016-01-01

    The paper provides a contribution for populating database of three physical parameters needed to model energy performance of buildings with green roofs: “coverage ratio” (σ_f), leaf area index (LAI) and leaf temperature (T_f). On purpose, six plant species were investigated experimentally: Phyla nordiflora, Aptenia lancifolia, Mesembryanthenum barbatus, Gazania nivea, Gazania uniflora, and Sedum. Proper ranges of the cited parameters have been found for each species. The here indicated ranges of σ_f values refer to different growth levels of the species in the same lapse of time, that is four months. Single measured LAI values are also reported for the same plants. As for the T_f (upper and lower layer), ranges of revealed temperatures refer to those detected from 10:30 a.m. to 16:30 p.m. of a selected day. Additionally, the dependence of T_f on climatic parameters was investigated. A linear equation resulted the best fitting curve for all experimental T_f data and the corresponding solar radiation data (with autocorrelation coefficients between 0.80 and 0.98). Furthermore, the effect potentially produced on building energy consumption by these species was analyzed using a simulation tool. Estimated cooling energy savings range approximately between 8% and 20% depending on adopted plants. - Highlights: • Green roof modeling requires the knowledge of various physical parameters. • Coverage ratio, leaf area index and leaves temperatures were measured for six species. • A tentative correlation between leaf temperature and climatic parameters was shown. • A correlation between LAI and coverage ratio was checked and discussed. • Potential effects of studied species on building energy consumption were investigated.

  7. An experimental analysis of illumination intensity and temperature dependency of photovoltaic cell parameters

    International Nuclear Information System (INIS)

    Cuce, Erdem; Cuce, Pinar Mert; Bali, Tulin

    2013-01-01

    Highlights: • R sh is rather sensitive to the variations in T c . • For higher G values, G ∗ is not affected from the variations in light intensity. • Ideality factor decreases linearly with increasing T c . • A linear decrease of R s and R sh has been observed with increasing T c . • Fill factor increases exponentially with G while it decreases linearly with T c . - Abstract: It is well known that accurate knowledge of photovoltaic cell parameters from the measured current–voltage characteristics is of vital importance for the quality control and the performance assessment of photovoltaic cells/modules. Although many attempts have been made so far for a thorough analysis of cell parameters, there are still significant discrepancies between the previously published results. In this regard, a detailed investigation of cell parameters through a comprehensive experimental and statistical work is important to elucidate the aforementioned contradictions. Therefore in the present work, effects of two main environmental factors on performance parameters of mono-crystalline and poly-crystalline silicon photovoltaic modules have been experimentally investigated. The experiments have been carried out under a calibrated solar simulator for various intensity levels and cell temperatures in the range 200–500 W/m 2 and 15–60 °C, respectively. The results indicated that light intensity has a dominant effect on current parameters. Photocurrent, short circuit current and maximum current increase linearly with increasing intensity level. A new term, solar intensity coefficient, has been defined first time to characterize the solar radiation dependency of current parameters. On the other hand, it has been observed that cell temperature has a dramatic effect on voltage parameters. Open circuit voltage and maximum voltage considerably decrease with increasing cell temperature. Temperature coefficients of voltage parameters have been calculated for each case. Shunt

  8. Calculation of kinetic parameters of Caliban metallic core experimental reactor from stochastic neutron measurements

    Energy Technology Data Exchange (ETDEWEB)

    Casoli, P.; Authier, N.; Baud, J. [Commissariat a l' energie Atomique, Centre de Valduc, 21120 Is-sur-Tille (France)

    2009-07-01

    Several experimental devices are operated by the Criticality and Neutron Science Research Department of the CEA Valduc Laboratory. One of these is the metallic core reactor Caliban. The knowledge of the fundamental kinetic parameters of the reactor is very useful, indeed necessary, to the operator. The purpose of this study was to develop and perform experiments allowing to determinate some of these parameters. The prompt neutron decay constant and particularly its value at criticality can be measured with reactor noise techniques such as the interval-distribution, the Feynman variance-to-mean, and the Rossi-{alpha} methods. By introducing the Nelson number, the effective delayed neutron fraction and the average neutron lifetime can also be calculated with the Rossi-{alpha} method. Subcritical, critical, and even supercritical experiments were performed. With the Rossi-{alpha} technique, it was found that the prompt neutron decay constant at criticality was (6.02*10{sup 5} {+-} 9%). Experiments also brought out the limitations of the used experimental parameters. (authors)

  9. Correlating neutron yield and reliability for selecting experimental parameters for a plasma focus machine

    International Nuclear Information System (INIS)

    Pross, G.

    Possibilities of optimizing focus machines with a given energy content in the sense of high neutron yield and high reliability of the discharges are investigated experimentally. For this purpose, a focus machine of the Mather type with an energy content of 12 kJ was constructed. The following experimental parameters were varied: the material of the insulator in the ignition zone, the structure of the outside electrode, the length of the inside electrode, the filling pressure and the amount and polarity of the battery voltage. An important part of the diagnostic program consists of measurements of the azimuthal and axial current distribution in the accelerator, correlated with short-term photographs of the luminous front as a function of time. The results are given. A functional schematic has been drafted for focus discharge as an aid in extensive optimization of focus machines, combining findings from theory and experiments. The schematic takes into account the multiparameter character of the discharge and clarifies relationships between the experimental parameters and the target variables neutron yield and reliability

  10. Objective image quality parameters of relevance in practice, measured for film-screen combinations - a contribution to quality assurance activities

    International Nuclear Information System (INIS)

    Angerstein, W.; Wolf, M.

    1986-01-01

    Objective measurement of the physico-technical parameters determining the image quality is the fastest and most accurate method of quality testing of the systems. The parameters in case of X-ray intensifying screens are imaging quality, servicable life, and mechanical properties. (orig./DG) [de

  11. Three-dimensional FEM model of FBGs in PANDA fibers with experimentally determined model parameters

    Science.gov (United States)

    Lindner, Markus; Hopf, Barbara; Koch, Alexander W.; Roths, Johannes

    2017-04-01

    A 3D-FEM model has been developed to improve the understanding of multi-parameter sensing with Bragg gratings in attached or embedded polarization maintaining fibers. The material properties of the fiber, especially Young's modulus and Poisson's ratio of the fiber's stress applying parts, are crucial for accurate simulations, but are usually not provided by the manufacturers. A methodology is presented to determine the unknown parameters by using experimental characterizations of the fiber and iterative FEM simulations. The resulting 3D-Model is capable of describing the change in birefringence of the free fiber when exposed to longitudinal strain. In future studies the 3D-FEM model will be employed to study the interaction of PANDA fibers with the surrounding materials in which they are embedded.

  12. Evaluation of Experimental Parameters in the Accelerated Aging of Closed-Cell Foam Insulation

    Energy Technology Data Exchange (ETDEWEB)

    Stovall, Therese K [ORNL; Vanderlan, Michael [ORNL; Atchley, Jerald Allen [ORNL

    2012-12-01

    The thermal conductivity of many closed-cell foam insulation products changes over time as production gases diffuse out of the cell matrix and atmospheric gases diffuse into the cells. Thin slicing has been shown to be an effective means of accelerating this process in such a way as to produce meaningful results. Efforts to produce a more prescriptive version of the ASTM C1303 standard test method led to the ruggedness test described here. This test program included the aging of full size insulation specimens for time periods of five years for direct comparison to the predicted results. Experimental parameters under investigation include: slice thickness, slice origin (at the surface or from the core of the slab), thin slice stack composition, product facings, original product thickness, product density, and product type. The test protocol has been completed and this report provides a detailed evaluation of the impact of the test parameters on the accuracy of the 5-year thermal conductivity prediction.

  13. Experimental determination of solubility parameters of oils as a function of pressure

    DEFF Research Database (Denmark)

    Verdier, Sylvain Charles Roland; Duong, Diep; Andersen, Simon Ivar

    2005-01-01

    In this work, the solubility parameter of dead and live crude oils was measured at 303.15 K and up to 300 bar, using the internal pressure approach. An indirect technique was chosen, using thermal expansivities (determined from microcalorimetric measurements) and isothermal compressibilities (cal...... are measured and given as input. Therefore, a more appropriate characterization method should give better results....... (calculated from density measurements). This method was tested on seven pure compounds, and the deviation with literature data is method based on the refractive index was used to examine the validity of the results for the oils, and a deviation of ... parameter was also calculated from two cubic equations of state and compared to experimental results. In this case, the deviations are larger (up to 6.5 MPa1/2), whereas this approach gives accurate results for pure compounds. This might be due to the characterization procedure, because the volumes...

  14. On determination of microphone response and other parameters by a hybrid experimental and numerical method

    DEFF Research Database (Denmark)

    Barrera Figueroa, Salvador; Jacobsen, Finn; Rasmussen, Knud

    2008-01-01

    to this problem is to measure the velocity distribution of the membrane by means of a non-contact method, such as laser vibrometry. The measured velocity distributions can be used together with a numerical formulation such as the Boundary Element Method for estimating the microphone response and other parameters...... such as the acoustic centres. In this work, a hybrid method is presented. The velocity distributions of condenser Laboratory Standard microphones were measured using a laser vibrometer. This measured velocity distribution was used for estimating the microphone responses and parameters. The agreement with experimental......Typically, numerical calculations of the pressure, free-field and random-incidence response of a condenser microphone are carried out on the basis of an assumed displacement distribution of the diaphragm of the microphone; the conventional assumption is that the displacement follows a Bessel...

  15. Experimental Characterization of Ultra-Wideband Channel Parameter Measurements in an Underground Mine

    Directory of Open Access Journals (Sweden)

    B. Nkakanou

    2011-01-01

    Full Text Available Experimental results for an ultra-wideband (UWB channel parameters in an underground mining environment over a frequency range of 3 GHz to 10 GHz are reported. The measurements were taken both in LOS and NLOS cases in two different size mine galleries. In the NLOS case, results were acquired for different corridor obstruction angles. The results were obtained during an extensive measurement campaign in the UWB frequency, and the measurement procedure allows both the large- and small-scale parameters such as the path loss exponent, coherence bandwidth, and so forth, to be quantified. The capacity of the UWB channel as a function of the physical depth of the mine gallery has also been recorded for comparison purposes.

  16. Changes in the basic experimental parameters of capillary gas chromatography in the 20th century.

    Science.gov (United States)

    Berezkin, V G; Viktorova, E N

    2003-01-24

    Studies of qualitative changes in capillary gas chromatography are of significant practical and scientific interest. This paper analyzes the evolution of the most important experimental chromatographic parameters over the last three decades and is based on the use of a new approach to scientometrical research that is referred to as applied scientometry. One essential feature of this approach is that it looks at the entire contents of each paper rather than only taking account its title, abstract. and references (as is typical for conventional scientometry). In this paper, we monitor how the most important chromatographic parameters, such as column length and diameter, layer thickness, stationary liquid phases, separation temperature mode. etc., have been evolving over the period 1970-2000. We used data from the following journals: Chromatographia, Journal of Chromatography, and Journal of High Resolution Chromatography and Chromatography Communications.

  17. 2000 CKM-triangle analysis a critical review with updated experimental inputs and theoretical parameters

    International Nuclear Information System (INIS)

    Roudeau, P.; Stocchi, A.; Ciuchini, M.; Lubicz, V.; D'Agostini, G.; Franco, E.; Martinelli, G.; Parodi, F.

    2000-12-01

    Within the Standard Model, a review of the current determination of the sides and angles of the CKM unitarity triangle is presented, using experimental constraints from the measurements of |ε K |, |V ub /V cb |, Δm d and from the limit on Δm s , available in September 2000. Results from the experimental search for B 0 s -B-bar 0 s oscillations are introduced in the present analysis using the likelihood. Special attention is devoted to the determination of the theoretical uncertainties. The purpose of the analysis is to infer regions where the parameters of interest lie with given probabilities. The BaBar '95% C.L. scanning' method is also commented. (authors)

  18. Experimental evaluation of local bubble parameters of subcooled boiling flow in a pressurized vertical annulus channel

    Energy Technology Data Exchange (ETDEWEB)

    Chu, In-Cheol, E-mail: chuic@kaeri.re.kr; Lee, Seung-Jun; Youn, Young Jung; Park, Jong Kuk; Choi, Hae Seob; Euh, Dong-Jin; Song, Chul-Hwa

    2017-02-15

    Experiments were performed to quantify the local bubble parameters such as void fraction, bubble velocity, interfacial area concentration, and Sauter mean diameter for the subcooled boiling flow of a refrigerant R-134a in a pressurized vertical annulus channel. Optical fiber void probe and double pressure boundary visualization windows were installed at four measurement stations with different elevations, thus enabling the quantification of local bubble parameters and observation of global boiling structure. Using high-resolution traverse systems for the optical fiber void probes and the heating tube, the radial profiles of the bubble parameters and their axial propagation can be evaluated at any elevation of the whole heating region. At this first phase of the experiments, three tests were conducted by varying the pressure, heat flux, mass flux, and local liquid subcooling. The radial profiles of the bubble parameters were obtained at seven elevations. The pressure condition of the present experiments covered the normal operating pressure of PWRs according to the similarity criteria. The present experimental data will be useful for thorough validation and improvement of the CMFD (Computation Multi-Fluid Dynamics) codes and constitutive relations.

  19. Experimental study on characteristics of interfacial parameter distribution for upward bubbly flow in inclined tube

    International Nuclear Information System (INIS)

    Xing Dianchuan; Yan Changqi; Sun Licheng; Liu Jingyu

    2013-01-01

    Experimental study on characteristics of interfacial parameter distribution for air-water bubbly flow in an inclined circular tube was performed by using the double sensor probe method. Parameters including radial distributions of local void fraction, bubble passing frequency, interfacial area concentration and bubble equivalent diameter were measured using the probe. The inner diameter of test section is 50 mm, and the liquid superficial velocity is 0.144 m/s, with the gas superficial velocity ranging from 0 to 0.054 m/is. The results show that bubbles obviously move toward the upper wall and congregate. The local interfacial area concentration, bubble passing frequency and void fraction have similar radial distribution profiles. Different from the vertical condition, for a cross-sectional area of the test section, the peak value near the upper side increases, while decreases or even disappears near the underside. The local parameter increases as the radial positions change from lower to upper location, and the increased slope becomes larger as the inclination angles increase. The equivalent bubble diameter doesn't vary with radial position, superficial gas velocity and inclination angle, and bubble aggregation and breaking up nearly doesn't occur. The mechanism of effects of inclination on local parameter distribution for bubbly flow is explained by analyzing the transverse force governing the bubble motion. (authors)

  20. A combined experimental and analytical approach for interface fracture parameters of dissimilar materials in electronic packages

    International Nuclear Information System (INIS)

    Kay, N.R.; Ghosh, S.; Guven, I.; Madenci, E.

    2006-01-01

    This study concerns the development of a combined experimental and analytical technique to determine the critical values of fracture parameters for interfaces between dissimilar materials in electronic packages. This technique utilizes specimens from post-production electronic packages. The mechanical testing is performed inside a scanning electron microscope while the measurements are achieved by means of digital image correlation. The measured displacements around the crack tip are used as the boundary conditions for the analytical model to compute the energy release rate. The critical energy release rate values obtained from post-production package specimens are obtained to be lower than those laboratory specimens

  1. Experimental parameters for quantitative surface analysis by medium energy ion scattering, ch. 1

    International Nuclear Information System (INIS)

    Turkenburg, W.C.; Kersten, H.H.; Colenbrander, B.G.; Jongh, A.P. de; Saris, F.W.

    1976-01-01

    A new UHV chamber for surface and surface layer analysis by collision spectroscopy of backscattered ions at medium energies is described. Experimental parameters like energy, angular and depth resolution, crystal alignment and background pressure are discussed. Formulae based on the use of an electrostatic energy analyser show that the analysis can be quantitative. Effects of beam induced build-up of a hydro-carbon layer, sputter cleaning and creation of radiation damage have been investigated for Cu (110) and Ni (110). Detection sensitivity for Carbon, Oxygen and Sulfur on Cu and Ni has been found to be 0.2, 0.1 and 0.03 of a monolayer respectively

  2. Optimizing experimental parameters for the projection requirement in HAADF-STEM tomography

    Energy Technology Data Exchange (ETDEWEB)

    Aveyard, R., E-mail: r.a.aveyard@tudelft.nl [Department of Imaging Physics, Delft University of Technology, 2628CJ Delft (Netherlands); Zhong, Z.; Batenburg, K.J. [Centrum Wiskunde and Informatica, Science Park 123, NL-1098 XG Amsterdam (Netherlands); Rieger, B., E-mail: b.rieger@tudelft.nl [Department of Imaging Physics, Delft University of Technology, 2628CJ Delft (Netherlands)

    2017-06-15

    Highlights: • The extent to which HAADF-STEM meets the projection requirement has been studied. • Multislice simulations used to model beam propagation and study signal linearity. • Propagation in crystalline and amorphous materials considered. • Optimal experimental set-up for the projection requirement is discussed. - Abstract: Tomographic reconstruction algorithms offer a means by which a tilt-series of transmission images can be combined to yield a three dimensional model of the specimen. Conventional reconstruction algorithms assume that the measured signal is a linear projection of some property, typically the density, of the material. Here we report the use of multislice simulations to investigate the extent to which this assumption is met in HAADF-STEM imaging. The use of simulations allows for a systematic survey of a range of materials and microscope parameters to inform optimal experimental design. Using this approach it is demonstrated that the imaging of amorphous materials is in good agreement with the projection assumption in most cases. Images of crystalline specimens taken along zone-axes are found to be poorly suited for conventional linear reconstruction algorithms due to channelling effects which produce enhanced intensities compared with off-axis images, and poor compliance with the projection requirement. Off-axis images are found to be suitable for reconstruction, though they do not strictly meet the linearity requirement in most cases. It is demonstrated that microscope parameters can be selected to yield improved compliance with the projection requirement.

  3. Optimizing experimental parameters for the projection requirement in HAADF-STEM tomography

    International Nuclear Information System (INIS)

    Aveyard, R.; Zhong, Z.; Batenburg, K.J.; Rieger, B.

    2017-01-01

    Highlights: • The extent to which HAADF-STEM meets the projection requirement has been studied. • Multislice simulations used to model beam propagation and study signal linearity. • Propagation in crystalline and amorphous materials considered. • Optimal experimental set-up for the projection requirement is discussed. - Abstract: Tomographic reconstruction algorithms offer a means by which a tilt-series of transmission images can be combined to yield a three dimensional model of the specimen. Conventional reconstruction algorithms assume that the measured signal is a linear projection of some property, typically the density, of the material. Here we report the use of multislice simulations to investigate the extent to which this assumption is met in HAADF-STEM imaging. The use of simulations allows for a systematic survey of a range of materials and microscope parameters to inform optimal experimental design. Using this approach it is demonstrated that the imaging of amorphous materials is in good agreement with the projection assumption in most cases. Images of crystalline specimens taken along zone-axes are found to be poorly suited for conventional linear reconstruction algorithms due to channelling effects which produce enhanced intensities compared with off-axis images, and poor compliance with the projection requirement. Off-axis images are found to be suitable for reconstruction, though they do not strictly meet the linearity requirement in most cases. It is demonstrated that microscope parameters can be selected to yield improved compliance with the projection requirement.

  4. An Empirical Study of Parameter Estimation for Stated Preference Experimental Design

    Directory of Open Access Journals (Sweden)

    Fei Yang

    2014-01-01

    Full Text Available The stated preference experimental design can affect the reliability of the parameters estimation in discrete choice model. Some scholars have proposed some new experimental designs, such as D-efficient, Bayesian D-efficient. But insufficient empirical research has been conducted on the effectiveness of these new designs and there has been little comparative analysis of the new designs against the traditional designs. In this paper, a new metro connecting Chengdu and its satellite cities is taken as the research subject to demonstrate the validity of the D-efficient and Bayesian D-efficient design. Comparisons between these new designs and orthogonal design were made by the fit of model and standard deviation of parameters estimation; then the best model result is obtained to analyze the travel choice behavior. The results indicate that Bayesian D-efficient design works better than D-efficient design. Some of the variables can affect significantly the choice behavior of people, including the waiting time and arrival time. The D-efficient and Bayesian D-efficient design for MNL can acquire reliability result in ML model, but the ML model cannot develop the theory advantages of these two designs. Finally, the metro can handle over 40% passengers flow if the metro will be operated in the future.

  5. Experimental study of dual fuel engine performance using variable LPG composition and engine parameters

    International Nuclear Information System (INIS)

    Elnajjar, Emad; Selim, Mohamed Y.E.; Hamdan, Mohammad O.

    2013-01-01

    Highlights: • The effect of using variable LPG is studied. • Five fuels with propane to butane % volume ratio are: 100-70-55-25-0. • 100% Propane composition shows the highest noise levels with similar performance. • At 45° BTDC injection timing 55% Propane LPG the only fuel experience knocking. • LPG fuels gave similar engine performance, with differences in levels of noise. - Abstract: The present work investigates experimentally the effect of LPG fuel with different composition and engine parameters on the performance of a dual compression engine. Five different blends of LPG fuels are used with Propane to Butane volume ratio of 100:0, 70:30, 55:45, 25:75, and 0:100. A single cylinder, naturally aspirated, four strokes, indirectly injected, water cooled modified Ricardo E6 engine, is used in this study. The study is carried out by measuring the cylinder pressure, engine load, engine speed, crank angle, and the fuel’s flow rate. The engine performance under variable LPG fuel composition, engine load, pilot fuel injection timing, compression ratio, pilot fuel mass and engine speed, are estimated by comparing the following engine parameters: the cylinder maximum pressure, the indicated mean effective pressure, the maximum rate of pressure rise, and the thermal efficiency. The experimental data indicates that the engine parameters are playing a major role on the engine’s performance. Different LPG fuel composition did not show a major effect on the engine efficiency but directly impacted the levels of generated combustion noise

  6. Electrodialytic desalination of brackish water: determination of optimal experimental parameters using full factorial design

    Science.gov (United States)

    Gmar, Soumaya; Helali, Nawel; Boubakri, Ali; Sayadi, Ilhem Ben Salah; Tlili, Mohamed; Amor, Mohamed Ben

    2017-12-01

    The aim of this work is to study the desalination of brackish water by electrodialysis (ED). A two level-three factor (23) full factorial design methodology was used to investigate the influence of different physicochemical parameters on the demineralization rate (DR) and the specific power consumption (SPC). Statistical design determines factors which have the important effects on ED performance and studies all interactions between the considered parameters. Three significant factors were used including applied potential, salt concentration and flow rate. The experimental results and statistical analysis show that applied potential and salt concentration are the main effect for DR as well as for SPC. The effect of interaction between applied potential and salt concentration was observed for SPC. A maximum value of 82.24% was obtained for DR under optimum conditions and the best value of SPC obtained was 5.64 Wh L-1. Empirical regression models were also obtained and used to predict the DR and the SPC profiles with satisfactory results. The process was applied for the treatment of real brackish water using the optimal parameters.

  7. Comparison of Instrumentation and Control Parameters Based on Simulation and Experimental Data for Reactor TRIGA PUSPATI

    International Nuclear Information System (INIS)

    Anith Khairunnisa Ghazali; Mohd Sabri Minhat

    2015-01-01

    Reactor TRIGA PUSPATI (RTP) undergoes safe operation for more than 30 years and the only research reactor in Malaysia. The main safety feature of Instrumentation and Control (I and C) system design is such that any failure in the electronic, or its associated components, does not lead to an uncontrolled rate of reactivity. There are no best models for RTP simulation was designed for study and research. Therefore, the comparison for I&C parameters are very essential, to design the best RTP model using MATLAB/ Simulink as close as the RTP. The simulation of TRIGA reactor type already develop using desktop reactor simulator such as Personal Computer Transient Analyzer (PCTRAN). The experimental data from RTP and simulation of PCTRAN shows some similarities and differences due to certain limitation. Currently, the structured RTP simulation was designed using MATLAB and Simulink tool that consist of ideal fission chamber, controller, control rod position, height to worth and RTP model. The study on this paper focus on comparison between real data from RTP and simulation result from PCTRAN on I&C parameters such as water level, fuel temperature, bulk temperature, power rated and rod position. The error analysis due to some similarities and differences of I&C parameters shall be obtained and analysed. The result will be used as reference for proposed new structured of RTP model. (author)

  8. Investigating dynamic parameters in HWZPR ased on the experimental and calculated results

    Energy Technology Data Exchange (ETDEWEB)

    Nasrazadani, Zahra; Behfamia, Manochehar; Khosandi, Jamshid; Mirvakili, Mohammad [Reactors Research School, Nuclear Science And Technology Research Institute, Atomic Energy Organization of Iran, Esfahan (Iran, Islamic Republic of)

    2016-10-15

    The neutron decay constant, α, and effective delayed neutron fraction, β{sub eff}, are important parameters for the control of the dynamic behavior of nuclear reactors. For the heavy water zero power reactor (HWZPR), this document describes the measurements of the neutron decay constant by noise analysis methods, including variance to mean (VTM) ratio and endogenous pulse source (EPS) methods. The measured α is successively used to determine the experimental value of the effective delayed neutron fraction as well. According to the experimental results, β{sub eff} of the HWZPR reactor under study is equal to 7.84e-3. This value is finally used to validate the calculation of the effective delayed neutron fraction by the Monte Carlo methods that are discussed in the document. Using the Monte Carlo N-Particle (MCNP)-4C code, a β{sub eff} value of 7.58e-3 was obtained for the reactor under study. Thus, the relative difference between the β{sub eff} values determined experimentally and by Monte Carlo methods was estimated to be < 4%.

  9. Deriving amplification factors from simple site parameters using generalized regression neural networks: implications for relevant site proxies

    Science.gov (United States)

    Boudghene Stambouli, Ahmed; Zendagui, Djawad; Bard, Pierre-Yves; Derras, Boumédiène

    2017-07-01

    Most modern seismic codes account for site effects using an amplification factor (AF) that modifies the rock acceleration response spectra in relation to a "site condition proxy," i.e., a parameter related to the velocity profile at the site under consideration. Therefore, for practical purposes, it is interesting to identify the site parameters that best control the frequency-dependent shape of the AF. The goal of the present study is to provide a quantitative assessment of the performance of various site condition proxies to predict the main AF features, including the often used short- and mid-period amplification factors, Fa and Fv, proposed by Borcherdt (in Earthq Spectra 10:617-653, 1994). In this context, the linear, viscoelastic responses of a set of 858 actual soil columns from Japan, the USA, and Europe are computed for a set of 14 real accelerograms with varying frequency contents. The correlation between the corresponding site-specific average amplification factors and several site proxies (considered alone or as multiple combinations) is analyzed using the generalized regression neural network (GRNN). The performance of each site proxy combination is assessed through the variance reduction with respect to the initial amplification factor variability of the 858 profiles. Both the whole period range and specific short- and mid-period ranges associated with the Borcherdt factors Fa and Fv are considered. The actual amplification factor of an arbitrary soil profile is found to be satisfactorily approximated with a limited number of site proxies (4-6). As the usual code practice implies a lower number of site proxies (generally one, sometimes two), a sensitivity analysis is conducted to identify the "best performing" site parameters. The best one is the overall velocity contrast between underlying bedrock and minimum velocity in the soil column. Because these are the most difficult and expensive parameters to measure, especially for thick deposits, other

  10. The impact of confinement scaling on ITER [International Thermonuclear Experimental Reactor] parameters

    International Nuclear Information System (INIS)

    Reid, R.L.; Galambos, J.D.; Peng, Y.K.M.

    1988-09-01

    Energy confinement scaling is a major concern in the design of the International Thermonuclear Experimental Reactor (ITER). The existing database for tokamaks can be fitted with a number of different confinement scaling expressions that have similar degrees of approximation. These scaling laws predict confinement times for ITER that vary by over an order of magnitude. The uncertainties in the form and magnitude of these scaling laws must be substantially reduced before the plasma performance of ITER can be predicted with adequate reliability. The TETRA systems code is used to calculate the dependence of major ITER parameters on the scaling laws currently in use. Design constraints of interest in the present phase of ITER consideration are used, and the minimum-cost devices arising from these constraints are reviewed. 9 refs., 13 figs., 4 tabs

  11. Experimental determination of the x-ray atomic fundamental parameters of nickel

    Science.gov (United States)

    Ménesguen, Y.; Lépy, M.-C.; Hönicke, P.; Müller, M.; Unterumsberger, R.; Beckhoff, B.; Hoszowska, J.; Dousse, J.-Cl; Błachucki, W.; Ito, Y.; Yamashita, M.; Fukushima, S.

    2018-02-01

    The x-ray atomic properties of nickel (Ni) were investigated in a unique approach combining different experimental techniques to obtain new, useful and reliable values of atomic fundamental parameters for x-ray spectrometric purposes and for comparison with theoretical predictions. We determined the mass attenuation coefficients in an energy range covering the L- and K-absorption edges, the K-shell fluorescence yield and the Kβ/Kα and Kβ1, 3/Kα1, 2 transition probability ratios. The obtained line profiles and linewidths of the Kα and Kβ transitions in Ni can be considered as the contribution of the satellite lines arising from the [KM] shake processes suggested by Deutsch et al (1995 Phys. Rev. A 51 283) and Ito et al (2016 Phys. Rev. A 94 042506). Comparison of the new data with several databases showed good agreement, but also discrepancies were found with existing tabulated values.

  12. Experimental research on dispersion parameters of ground water around the area of CIAE

    International Nuclear Information System (INIS)

    Yu Jun

    1993-01-01

    The dispersion are important parameters in modeling the migration of pollutant in the ground water. Due to the complexity of geological media, variant dispersion is expected according to the difference of the geological media. Three parts are included in physical simulation in the laboratory column, tracer experiment in the field and the prediction of dispersion using the stochastic model. Experimental results show that the dispersion obtained in the column are three orders of magnitude smaller than that obtained in the field. Using the field values of conductivity and stochastic theory, the calculated asymptotic longitudinal and lateral dispersion are 370 and 0.45 meters respectively and the correlation length is 400 meters approximately. Using the dispersion obtained from the formula in the paper can enhance the precision of the model prediction, the distance heeded to reach the Fick's dispersion is 6 km approximately

  13. [Experimental rationale for the parameters of a rapid method for oxidase activity determination].

    Science.gov (United States)

    Butorina, N N

    2010-01-01

    Experimental rationale is provided for the parameters of a rapid (1-2-min) test to concurrently determine the oxidase activity of all bacteria grown on the membrane filter after water filtration. Oxidase reagents that are the aqueous solutions of tetramethyl-p-phenylenediamine dihydrochloride and demethyl-p-phenylenediamine dihydrochloride have been first ascertained to exert no effect on the viability and enzymatic activity of bacteria after one-hour contact. An algorithm has been improved for the rapid oxidase activity test: the allowable time for bacteria to contact oxidase reagents and procedures for minimizing the effect on bacterial biochemical activity following the contact. An accelerated method based on lactose medium with tergitol 7 and Endo agar has been devised to determine coliform bacteria, by applying the rapid oxidase test: the time of a final response is 18-24 hours. The method has been included into GOST 52426-2005.

  14. Experimental design optimisation: theory and application to estimation of receptor model parameters using dynamic positron emission tomography

    International Nuclear Information System (INIS)

    Delforge, J.; Syrota, A.; Mazoyer, B.M.

    1989-01-01

    General framework and various criteria for experimental design optimisation are presented. The methodology is applied to estimation of receptor-ligand reaction model parameters with dynamic positron emission tomography data. The possibility of improving parameter estimation using a new experimental design combining an injection of the β + -labelled ligand and an injection of the cold ligand is investigated. Numerical simulations predict remarkable improvement in the accuracy of parameter estimates with this new experimental design and particularly the possibility of separate estimations of the association constant (k +1 ) and of receptor density (B' max ) in a single experiment. Simulation predictions are validated using experimental PET data in which parameter uncertainties are reduced by factors ranging from 17 to 1000. (author)

  15. A comparative study of parameters used in design and operation of desalination experimental facility versus the process parameters in a commercial desalination plant

    International Nuclear Information System (INIS)

    Hanra, M.S.; Verma, R.K.; Ramani, M.P.S.

    1982-01-01

    Desalination Experimental Facility (DEF) based on multistage flash desalination process has been set up by the Desalination Division of the Bhabha Atomic Research Centre, Bombay. The design parameters of DEF and materials used for various equipment and parts of DEF are mentioned. DEF was operated for 2300 hours in six operational runs. The range of operational parameters maintained during operation and observations on the performance of the materials of construction are given. Detailed comparison has been made for the orocess parameters in DEF and those in a large size plant. (M.G.B.)

  16. Relevant parameters in the micro silica selection for the self-flowing ultra-low cement castables production

    International Nuclear Information System (INIS)

    Studart, A.R.; Pandolfelli, V.C.; Rodrigues, J.A.; Vendrasco, S.L.

    1997-01-01

    Self-flowing ultra-low cement castables typically contain a large fraction of the particles, usually fume silica, which increase their flowability and mechanical strength at low temperatures. Fume silicas available in the market differ mainly from their amount of impurities. It is assumed that the content of soluble alkali and free carbon containing in this raw-material affects strongly the processing of self-flowing castable. In this work high alumina castables with gap-sized particle size distribution were prepared to evaluate their flowability, workability and mechanical strength for each sort of fume silica studied. It was observed that the amount of impurities affects both deflocculation and setting time of the castables and their cold and hot mechanical strength. Considerations regarding the physical and chemical characteristics relevant for selecting fume silicas for the production of self-flowing castables are presented and discussed. (author)

  17. Surgical Anatomy and Microvascular Surgical Technique Relevant to Experimental Renal Transplant in Rat Employing Aortic and Inferior Venacaval Conduits.

    Science.gov (United States)

    Shrestha, Badri Man; Haylor, John

    2017-11-15

    Rat models of renal transplant are used to investigate immunologic processes and responses to therapeutic agents before their translation into routine clinical practice. In this study, we have described details of rat surgical anatomy and our experiences with the microvascular surgical technique relevant to renal transplant by employing donor inferior vena cava and aortic conduits. For this study, 175 rats (151 Lewis and 24 Fisher) were used to establish the Fisher-Lewis rat model of chronic allograft injury at our institution. Anatomic and technical details were recorded during the period of training and establishment of the model. A final group of 12 transplanted rats were studied for an average duration of 51 weeks for the Lewis-to-Lewis isografts (5 rats) and 42 weeks for the Fisher-to-Lewis allografts (7 rats). Functional measurements and histology confirmed the diagnosis of chronic allograft injury. Mastering the anatomic details and microvascular surgical techniques can lead to the successful establishment of an experimental renal transplant model.

  18. Impact of errors in experimental parameters on reconstructed breast images using diffuse optical tomography.

    Science.gov (United States)

    Deng, Bin; Lundqvist, Mats; Fang, Qianqian; Carp, Stefan A

    2018-03-01

    largest deterioration due to cross-talk between signal channels. However, errors in optical images could be effectively controlled when experimental parameters were properly estimated during data acquisition and accounted for in the image processing procedure. Finally, optical images recovered using structural priors were, in general, less susceptible to experimental errors; however, lesion contrasts were more sensitive to errors when tumor locations were used as a priori info. Findings in this simulation study can provide guidelines for system design and operation in optical breast imaging studies.

  19. Experimental Research on The Deformability of a Geological Material: Initial Characterisation and Identification of Parameters

    International Nuclear Information System (INIS)

    Villar, M.V.; Udias, A.; Canamon, I.; Robles, J.

    2006-01-01

    This document reflects the work performed at CIEMAT (Engineered and Geological Barriers Group) in the framework of the RTD Project BTE2002-04244-C02-02 (DEF-NOSAT). The first phase of the project consisted on the selection and characterisation of a geological material fitted for unsaturated triaxial testing. The result obtained during this phase gave place to the selection of a silty clay from Alcala de Henares (Madrid, Spain). Compaction and permeability tests were performed as well as studies on mixtures of this soil with sand. With the selected mixtures (70/30 and 50/50 percent sand/soil) isotropic compression tests were carried out in the saturated sample. The results of these tests have allowed the determination of some of the parameters needed to model the mechanical behaviour of the soil. The report includes also a brief description of a methodology developed in the Department of Applied Mathematics and Computer Methods of the Universidad Politecnica de Madrid for getting these parameters by optimisation of the experimental results, as well as the results obtained. (Author) 25 refs

  20. Experimental Active Vibration Control in Truss Structures Considering Uncertainties in System Parameters

    Directory of Open Access Journals (Sweden)

    Douglas Domingues Bueno

    2008-01-01

    Full Text Available This paper deals with the study of algorithms for robust active vibration control in flexible structures considering uncertainties in system parameters. It became an area of enormous interest, mainly due to the countless demands of optimal performance in mechanical systems as aircraft, aerospace, and automotive structures. An important and difficult problem for designing active vibration control is to get a representative dynamic model. Generally, this model can be obtained using finite element method (FEM or an identification method using experimental data. Actuators and sensors may affect the dynamics properties of the structure, for instance, electromechanical coupling of piezoelectric material must be considered in FEM formulation for flexible and lightly damping structure. The nonlinearities and uncertainties involved in these structures make it a difficult task, mainly for complex structures as spatial truss structures. On the other hand, by using an identification method, it is possible to obtain the dynamic model represented through a state space realization considering this coupling. This paper proposes an experimental methodology for vibration control in a 3D truss structure using PZT wafer stacks and a robust control algorithm solved by linear matrix inequalities.

  1. Calculating the parameters of experimental data Gauss distribution using the least square fit method and evaluation of their accuracy

    International Nuclear Information System (INIS)

    Guseva, E.V.; Peregudov, V.N.

    1982-01-01

    The FITGAV program for calculation of parameters of the Gauss curve describing experimental data is considered. The calculations are based on the least square fit method. The estimations of errors in the parameter determination as a function of experimental data sample volume and their statistical significance are obtained. The curve fit using 100 points occupies less than 1 s at the SM-4 type computer

  2. Male reproductive system parameters in a two-generation reproduction study of ammonium perfluorooctanoate in rats and human relevance.

    Science.gov (United States)

    York, Raymond G; Kennedy, Gerald L; Olsen, Geary W; Butenhoff, John L

    2010-04-30

    Ammonium perfluorooctanoate (ammonium PFOA) is an industrial surfactant that has been used primarily as a processing aid in the manufacture of fluoropolymers. The environmental and metabolic stability of PFOA together with its presence in human blood and long elimination half-life have led to extensive toxicological studies in laboratory animals. Two recent publications based on observations from the Danish general population have reported: (1) a negative association between serum concentrations of PFOA in young adult males and their sperm counts and (2) a positive association among women with time to pregnancy. A two-generation reproduction study in rats was previously published (2004) in which no effects on functional reproduction were observed at doses up to 30mg ammonium PFOA/kg body weight. The article contained the simple statement: "In males, fertility was normal as were all sperm parameters". In order to place the recent human epidemiological data in perspective, herein we provide the detailed male reproductive parameters from that study, including sperm quality and testicular histopathology. Sperm parameters in rats from the two-generation study in all ammonium PFOA treatment groups were unaffected by treatment with ammonium PFOA. These observations reflected the normal fertility observations in these males. No evidence of altered testicular and sperm structure and function was observed in ammonium PFOA-treated rats whose mean group serum PFOA concentrations ranged up to approximately 50,000ng/mL. Given that median serum PFOA in the Danish cohorts was approximately 5ng/mL, it seems unlikely that concentrations observed in the general population, including those recently reported in Danish general population, could be associated causally with a real decrement in sperm number and quality.

  3. The study of influence of relevant physical parameters variations on the estimates of the effective doses of Rn-222

    International Nuclear Information System (INIS)

    Ridzikova, A.; Fronka, A.; Moucka, L.

    2004-01-01

    Based on the analysis of 12 weekly continuous measurements and 4 integral measurements performed in different seasons in actual apartment rooms, bedrooms in particular, we attempted to identify the uncertainties that are involved in the estimation of radiation doses to lung tissues. We found that the parameters of time of residence, concentration, and equilibrium factor can affect substantially the estimate of the overall early effective dose. The weekly averaged concentration measured in one term is not sufficient for a fairly accurate estimate; actually, the equilibrium factor f must also be known and the actual real individual time of residence must be estimated if we want to adopt this approach to the dose estimation

  4. A simplified model for predicting malaria entomologic inoculation rates based on entomologic and parasitologic parameters relevant to control.

    Science.gov (United States)

    Killeen, G F; McKenzie, F E; Foy, B D; Schieffelin, C; Billingsley, P F; Beier, J C

    2000-05-01

    Malaria transmission intensity is modeled from the starting perspective of individual vector mosquitoes and is expressed directly as the entomologic inoculation rate (EIR). The potential of individual mosquitoes to transmit malaria during their lifetime is presented graphically as a function of their feeding cycle length and survival, human biting preferences, and the parasite sporogonic incubation period. The EIR is then calculated as the product of 1) the potential of individual vectors to transmit malaria during their lifetime, 2) vector emergence rate relative to human population size, and 3) the infectiousness of the human population to vectors. Thus, impacts on more than one of these parameters will amplify each other's effects. The EIRs transmitted by the dominant vector species at four malaria-endemic sites from Papua New Guinea, Tanzania, and Nigeria were predicted using field measurements of these characteristics together with human biting rate and human reservoir infectiousness. This model predicted EIRs (+/- SD) that are 1.13 +/- 0.37 (range = 0.84-1.59) times those measured in the field. For these four sites, mosquito emergence rate and lifetime transmission potential were more important determinants of the EIR than human reservoir infectiousness. This model and the input parameters from the four sites allow the potential impacts of various control measures on malaria transmission intensity to be tested under a range of endemic conditions. The model has potential applications for the development and implementation of transmission control measures and for public health education.

  5. Theoretical and experimental evaluation of piezo-optic parameters and photoelastic constant in tetragonal PWO.

    Science.gov (United States)

    Natali, Pier Paolo; Montalto, Luigi; Daví, Fabrizio; Mengucci, Paolo; Ciriaco, Andrea; Paone, Nicola; Rinaldi, Daniele

    2018-02-01

    The tetragonal PbWO 4 (PWO) is one of the most important scintillating crystals, being used both in the Compact Muon Solenoid (CMS) experiment at the European Organization for Nuclear Research (CERN) and in the PANDA project at the Facility for Antiproton and Ion Research (FAIR). Light yield and other relevant scintillation properties depend, among many factors, also on the crystal mechanical quality. Accordingly, a detailed knowledge of crystal piezo-optic properties is a mandatory step toward understanding elasto-optic behavior and performing crystal quality control. In this paper, we evaluate for the first time, to the best of our knowledge, by means of both photoelastic and x-ray measurements, some components of the piezo-optic tensor; moreover, when the crystal is acted upon by a uniaxial stress, we obtain an evaluation for the rotation angle of the optic plane under stress as well as the photoelastic constant. These parameters are necessary to detect the residual stresses within the crystal, if any, and to give an overall quality measure. Such a methodology is in general suitable for any tetragonal crystals.

  6. An Experimental Seismic Data and Parameter Exchange System for Tsunami Warning Systems

    Science.gov (United States)

    Hoffmann, T. L.; Hanka, W.; Saul, J.; Weber, B.; Becker, J.; Heinloo, A.; Hoffmann, M.

    2009-12-01

    For several years GFZ Potsdam is operating a global earthquake monitoring system. Since the beginning of 2008, this system is also used as an experimental seismic background data center for two different regional Tsunami Warning Systems (TWS), the IOTWS (Indian Ocean) and the interim NEAMTWS (NE Atlantic and Mediterranean). The SeisComP3 (SC3) software, developed within the GITEWS (German Indian Ocean Tsunami Early Warning System) project, capable to acquire, archive and process real-time data feeds, was extended for export and import of individual processing results within the two clusters of connected SC3 systems. Therefore not only real-time waveform data are routed to the attached warning centers through GFZ but also processing results. While the current experimental NEAMTWS cluster consists of SC3 systems in six designated national warning centers in Europe, the IOTWS cluster presently includes seven centers, with another three likely to join in 2009/10. For NEAMTWS purposes, the GFZ virtual real-time seismic network (GEOFON Extended Virtual Network -GEVN) in Europe was substantially extended by adding many stations from Western European countries optimizing the station distribution. In parallel to the data collection over the Internet, a GFZ VSAT hub for secured data collection of the EuroMED GEOFON and NEAMTWS backbone network stations became operational and first data links were established through this backbone. For the Southeast Asia region, a VSAT hub has been established in Jakarta already in 2006, with some other partner networks connecting to this backbone via the Internet. Since its establishment, the experimental system has had the opportunity to prove its performance in a number of relevant earthquakes. Reliable solutions derived from a minimum of 25 stations were very promising in terms of speed. For important events, automatic alerts were released and disseminated by emails and SMS. Manually verified solutions are added as soon as they become

  7. The Numerical Calculation and Experimental Measurement of the Inductance Parameters for Permanent Magnet Synchronous Motor in Electric Vehicle

    Science.gov (United States)

    Jiang, Chao; Qiao, Mingzhong; Zhu, Peng

    2017-12-01

    A permanent magnet synchronous motor with radial magnetic circuit and built-in permanent magnet is designed for the electric vehicle. Finite element numerical calculation and experimental measurement are adopted to obtain the direct axis and quadrature axis inductance parameters of the motor which are vital important for the motor control. The calculation method is simple, the measuring principle is clear, the results of numerical calculation and experimental measurement are mutual confirmation. A quick and effective method is provided to obtain the direct axis and quadrature axis inductance parameters of the motor, and then improve the design of motor or adjust the control parameters of the motor controller.

  8. Experimental investigations relevant for hydrogen and fission product issues raised by the Fukushima accident

    Directory of Open Access Journals (Sweden)

    Sanjeev Gupta

    2015-02-01

    with the operation of passive safety systems in phenomena oriented and coupled effects experiments. In the present paper, potential hydrogen and fission product issues raised by the Fukushima accident are discussed. The discussion focuses on hydrogen and fission product behavior inside nuclear power plant containments under severe accident conditions. The relevant experimental investigations conducted in the technical scale containment THAI (thermal hydraulics, hydrogen, aerosols, and iodine test facility (9.2 m high, 3.2 m in diameter, and 60 m3 volume are discussed in the light of the Fukushima accident.

  9. Migration of radionuclides with ground water: a discussion of the relevance of the input parameters used in model calculations

    International Nuclear Information System (INIS)

    Jensen, B.S.

    1982-01-01

    It is probably obvious to all, that establishing the scientific basis of geological waste disposal by going deeper and deeper in detail, may fill out the working hours of hundreds of scientists for hundreds of years. Such an endeavor is, however, impossible to attain, and we are forced to define some criteria telling us and others when knowledge and insight is sufficient. In thepresent case of geological disposal one need to be able to predict migration behavior of a series of radionuclides under diverse conditions to ascertain that unacceptable transfer to the biosphere never occurs. We have already collected a huge amount of data concerning migration phenomena, some very useful, oter less so, but we still need investigatoins departing from the simple ideal concepts, which most often have provided modellers with input data to their calculations. I therefore advocate that basic research is pursued to the point where it is possible to put limits on the effect of the lesser known factors on the migration behavior of radionuclides. When such limits have been established, it will be possible to make calculations on the worst cases, which may also occur. Although I personally believe, that these extra investigations will prove additional safety in geological disposal, this fact will convince nobody, only experimental facts will do

  10. Arsenic mobilization in an oxidizing alkaline groundwater: Experimental studies, comparison and optimization of geochemical modeling parameters

    International Nuclear Information System (INIS)

    Hafeznezami, Saeedreza; Lam, Jacquelyn R.; Xiang, Yang; Reynolds, Matthew D.; Davis, James A.; Lin, Tiffany; Jay, Jennifer A.

    2016-01-01

    Arsenic (As) mobilization and contamination of groundwater affects millions of people worldwide. Progress in developing effective in-situ remediation schemes requires the incorporation of data from laboratory experiments and field samples into calibrated geochemical models. In an oxidizing aquifer where leaching of high pH industrial waste from unlined surface impoundments led to mobilization of naturally occurring As up to 2 mg L −1 , sequential extractions of solid phase As as well as, batch sediment microcosm experiments were conducted to understand As partitioning and solid-phase sorptive and buffering capacity. These data were combined with field data to create a series of geochemical models of the system with modeling programs PHREEQC and FITEQL. Different surface complexation modeling approaches, including component additivity (CA), generalized composite (GC), and a hybrid method were developed, compared and fitted to data from batch acidification experiments to simulate potential remediation scenarios. Several parameters strongly influence the concentration of dissolved As including pH, presence of competing ions (particularly phosphate) and the number of available sorption sites on the aquifer solids. Lowering the pH of groundwater to 7 was found to have a variable, but limited impact (<63%) on decreasing the concentration of dissolved As. The models indicate that in addition to lowering pH, decreasing the concentration of dissolved phosphate and/or increasing the number of available sorption sites could significantly decrease the As solubility to levels below 10 μg L −1 . The hybrid and GC modeling results fit the experimental data well (NRMSE<10%) with reasonable effort and can be implemented in further studies for validation. - Highlights: • Samples were collected from an oxidizing aquifer where high pH waste has led to mobilization of naturally occurring As. • Three surface complexation modeling approaches were used in modeling adsorption

  11. An Experimental Seismic Data and Parameter Exchange System for Interim NEAMTWS

    Science.gov (United States)

    Hanka, W.; Hoffmann, T.; Weber, B.; Heinloo, A.; Hoffmann, M.; Müller-Wrana, T.; Saul, J.

    2009-04-01

    In 2008 GFZ Potsdam has started to operate its global earthquake monitoring system as an experimental seismic background data centre for the interim NEAMTWS (NE Atlantic and Mediterranean Tsunami Warning System). The SeisComP3 (SC3) software, developed within the GITEWS (German Indian Ocean Tsunami Early Warning System) project was extended to test the export and import of individual processing results within a cluster of SC3 systems. The initiated NEAMTWS SC3 cluster consists presently of the 24/7 seismic services at IMP, IGN, LDG/EMSC and KOERI, whereas INGV and NOA are still pending. The GFZ virtual real-time seismic network (GEOFON Extended Virtual Network - GEVN) was substantially extended by many stations from Western European countries optimizing the station distribution for NEAMTWS purposes. To amend the public seismic network (VEBSN - Virtual European Broadband Seismic Network) some attached centres provided additional private stations for NEAMTWS usage. In parallel to the data collection by Internet the GFZ VSAT hub for the secured data collection of the EuroMED GEOFON and NEAMTWS backbone network stations became operational and the first data links were established. In 2008 the experimental system could already prove its performance since a number of relevant earthquakes have happened in NEAMTWS area. The results are very promising in terms of speed as the automatic alerts (reliable solutions based on a minimum of 25 stations and disseminated by emails and SMS) were issued between 2 1/2 and 4 minutes for Greece and 5 minutes for Iceland. They are also promising in terms of accuracy since epicenter coordinates, depth and magnitude estimates were sufficiently accurate from the very beginning, usually don't differ substantially from the final solutions and provide a good starting point for the operations of the interim NEAMTWS. However, although an automatic seismic system is a good first step, 24/7 manned RTWCs are mandatory for regular manual verification

  12. Experimental study on operating parameters of miniature loop heat pipe with flat evaporator

    International Nuclear Information System (INIS)

    Wang Shuangfeng; Huo Jiepeng; Zhang Xianfeng; Lin Zirong

    2012-01-01

    Miniature loop heat pipe (MLHP) with flat evaporator has been proved that it has the capability to fulfill the demand for the thermal management of high-power electronic system. To employ MLHP into practical application and obtain the best operating parameters, a copper-water MLHP with flat evaporator of 8 mm thick was fabricated and tested in the condition of different condenser locations and operating orientations. The results show that the condenser located close to the evaporator outlet and adverse orientation have positive impact on the operating temperature of the loop, but negative impact on the cooling capability of condenser. For better understanding of their effect on the heat transfer characteristics of MLHP, the start-up behaviors, thermal performance and the operating regimes are explored in detail. - Highlights: ► A copper-water MLHP with flat evaporator of only 8 mm thick was fabricated. ► The MLHP can be applied to electronic cooling. ► The effect of condenser locations was investigated for the first time. ► The experimental results were discussed and analyzed comprehensively. ► Some practical solutions for disadvantages of LHP operation were provided.

  13. Experimental studies on the effects of bolt parameters on the bearing characteristics of reinforced rock.

    Science.gov (United States)

    Cheng, Liang; Zhang, Yidong; Ji, Ming; Zhang, Kai; Zhang, Minglei

    2016-01-01

    Roadways supported by bolts contain support structures that are built into the rock surrounding the roadway, referred to as reinforced rocks in this paper. Using physical model simulation, the paper investigates the bearing characteristics of the reinforced rock under different bolt parameters with incrementally increased load. The experimental results show that the stress at the measurement point inside the structure varies with the kinetic pressure. The stress increases slowly as the load is initially applied, displays accelerated growth in the middle of the loading application, and decreases or remains constant in the later stage of the loading application. The change in displacement of the surrounding rock exhibits the following characteristics: a slow increase when the load is first applied, accelerated growth in the middle stage, and violent growth in the later stage. There is a good correlation between the change in the measured stress and the change in the surrounding rock displacement. Increasing the density of the bolt support and the length and diameter of the bolt improves the load-bearing performance of the reinforced rock, including its strength, internal peak stress, and residual stress. Bolting improves the internal structure of the surrounding rocks, and the deterioration of the surrounding rock decreases with the distance between the bolt supports.

  14. Design Parameters of Vortex Pumps: A Meta-Analysis of Experimental Studies

    Directory of Open Access Journals (Sweden)

    Angela Gerlach

    2017-01-01

    Full Text Available Vortex pumps can impel solid-containing fluids and are therefore widely applied, from wastewater transport to the food industry. Despite constant efforts to improve vortex pumps, however, they have remained relatively inefficient compared to conventional centrifugal pumps. To find an optimized design of vortex pumps, this paper provides a systematic analysis on experimental studies that investigated how variations in geometric parameters influence vortex pump characteristics, in particular the pump head, the pressure coefficient and the efficiency for best point operation. To this end, an extensive literature search was conducted, and eighteen articles with 53 primary investigations were identified and meta-integrated. This showed that it is not yet clarified how vortex pumps operate. Two different assumptions of the underlying operating principle of a vortex pump lead to diverging design principles. From the results of this meta-analysis, we deduce recommendations for a more efficient design of a vortex pump and emphasize further aspects on the underlying operating principle of a vortex pump.

  15. The reaction between iodine and silver under severe PWR accident conditions. An experimental parameter study

    Energy Technology Data Exchange (ETDEWEB)

    Funke, F; Greger, G U; Bleier, A; Hellmann, S; Morell, W [Siemens AG, Power Generation Group, Erlangen (Germany)

    1996-12-01

    An extensive experimental parameter study was performed on the kinetics in the reaction system I{sub 2}/Ag and I{sup -}/Ag in a laboratory-scale apparatus.Starting with I{sub 2} or I{sup -} solutions and silver powder suspensions, the decrease of soluted I{sub 2} or I{sup -}, respectively, due to fixation on the silver particles, was monitored as function of time using the radioactive tracer I-131. The measured data were analyzed using a model of first order kinetics with respect to the iodine concentration. However, the analysis using first order kinetics had to be performed separately in an early, fast reaction phase and in a late, slow reaction phase. The reason for this unexpected behaviour was not identified. Thus, rate constant, two for each test, were deduced from 14 I{sub 2}/Ag main tests and from 36 I{sup -}/Ag tests. No dependencies of the rate constants were found on the parameters temperature, initial iodine concentration, presence of boric acid, type of silver educt, and pretreatment of the silver educt prior to the tests. However, the stirring of the reaction solution generally enhanced the kinetics highlighting the importance of mass transfer. The I{sup -}/Ag reaction proceeded only if there was no inertization of the reaction solution by sparging with nitrogen. The temperature-independent rate constant for the early, fast I{sub 2}/Ag reaction phase is 2E-5 m/s. However, a smaller rate constant of 6E-6 m/s is recommended for use in source term calculations with IMPAIR, which already contains a first order model. Analogously, the temperature-independent I{sup -}/Ag reaction rate constant is 8E-6 m/s in an early, fast reaction phase. For use in source term calculations, a smaller rate constant of 2E-6 m/s is recommended. The lower bound of the I{sup -}/Ag rate constant was 3E-8 m/s which could be used in very conservative source term calculations. (author) 20 figs., 6 tabs., 15 refs.

  16. A Pre-normative study on the cyclic oxidation behaviour of PM chromium: the effect of experimental parameters

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, Y.P.; Haanappel, V.A.C.; Stroosnijder, M.F. [Commission of the European Communities, Ispra (Italy). Joint Research Centre; Caudron, E.; Buscail, H. [Lab. Vellave sur l' Elaboration et l' Etude des Materiaux, Equipe locale Univ. Blaise-Pascal Clermont-Fd 2 (France)

    2001-07-01

    In this study the importance of experimental parameters for the cyclic oxidation behaviour of chromium is discussed. In particular, the effect of different batches, sample geometry, maximum temperature during cyclic oxidation tests, and the effect of isothermal hold-time in relation to the oxidation behaviour are investigated in more detail. It is shown that small differences in the experimental method or material properties could already significantly influence the oxidation kinetics of the material under investigation. Consequently, poorly chosen and/or characterised experimental conditions can cause misleading results and even wrong conclusions. (orig.)

  17. Experimental and numerical investigations of oscillations in extracted material parameters for finite Bragg stacks using the NRW method

    DEFF Research Database (Denmark)

    Clausen, Niels Christian Jerichau; Arslanagic, Samel; Breinbjerg, Olav

    2012-01-01

    A 1D dielectric finite Bragg stack situated in a rectangular waveguide and illuminated by the fundamental TE10 mode is examined analytically, numerically, and experimentally. Calculated as well as measured scattering parameters are used to extract the effective/equivalent material parameters...... for three specific configurations of its constituent unit cell. Particular attention is devoted to the absence/presence of certain oscillations in the extracted material parameters, depending on the unit cell configuration. The results for the finite Bragg stack are further verified to agree with those...... of an infinite Bragg stack, for which the dispersion equation is used in conjunction with the Floquet-Bloch harmonics expansion to extract the material parameters. It is shown that the extracted material parameters for the finite and infinite Bragg stacks agree for the symmetric unit cell configuration....

  18. Gas migration in KBS-3 buffer bentonite. Sensitivity of test parameters to experimental boundary conditions

    International Nuclear Information System (INIS)

    Harrington, J.F.; Horseman, S.T.

    2003-01-01

    In the current Swedish repository design concept, hydrogen gas can be generated inside a waste canister by anaerobic corrosion of the ferrous metal liner. If the gas generation rate exceeds the diffusion rate of gas molecules in the buffer porewater, gas will accumulate in the void-space of a canister until its pressure becomes large enough for it to enter the bentonite as a discrete gaseous phase. Three long tenn gas injection tests have been performed on cylinders of pre-compacted MX80 bentonite. Two of these tests were undertaken using a custom-designed constant volume and radial flow (CVRF) apparatus. Gas was injected at a centrally located porous filter installed in the clay before hydration. Arrangements were made for gas to flow to three independently monitored sink-filter arrays mounted around the specimen. Axial and radial total stresses and internal porewater pressures were continuously monitored. Breakthrough and peak gas pressures were substantially larger than the sum of the swelling pressure and the external porewater. The third test was performed. using an apparatus which radially constrains the specimen during gas flow. Observed sensitivity of the breakthrough and peak gas pressures to the test boundary conditions suggests that gas entry must be accompanied by dilation of the bentonite fabric. In other words, there is a tendency for the volume of the specimen to increase during this process. The experimental evidence is consistent with the flow of gas along a relatively small number of crack-like pathways which propagate through the clay as gas pressure increases. Gas entry and breakthrough under constant volume boundary conditions causes a substantial increase in the total stress and the internal porewater pressure. It is possible to determine the point at which gas enters the clay by monitoring changes in these parameters. Localisation of gas flow within multiple pathways results, in nonuniform discharge rates at the sinks. When gas injection

  19. Bridges Dynamic Parameters Identification Based On Experimental and Numerical Method Comparison in Regard with Traffic Seismicity

    Science.gov (United States)

    Krkošková, Katarína; Papán, Daniel; Papánová, Zuzana

    2017-10-01

    The technical seismicity negatively affects the environment, buildings and structures. Technical seismicity means seismic shakes caused by force impulse, random process and unnatural origin. The vibration influence on buildings is evaluated in the Eurocode 8 in Slovak Republic, however, the Slovak Technical Standard STN 73 0036 includes solution of the technical seismicity. This standard also classes bridges into the group of structures that are significant in light of the technical seismicity - the group “U”. Using the case studies analysis by FEM simulation and comparison is necessary because of brief norm evaluation of this issue. In this article, determinate dynamic parameters by experimental measuring and numerical method on two real bridges are compared. First bridge, (D201 - 00) is Scaffold Bridge on the road I/11 leading to the city of Čadca and is situated in the city of Žilina. It is eleven - span concrete road bridge. The railway is the obstacle, which this bridge spans. Second bridge (M5973 Brodno) is situated in the part of Žilina City on the road of I/11. It is concrete three - span road bridge built as box girder. The computing part includes 3D computational models of the bridges. First bridge (D201 - 00) was modelled in the software of IDA Nexis as the slab - wall model. The model outputs are natural frequencies and natural vibration modes. Second bridge (M5973 Brodno) was modelled in the software of VisualFEA. The technical seismicity corresponds with the force impulse, which was put into this model. The model outputs are vibration displacements, velocities and accelerations. The aim of the experiments was measuring of the vibration acceleration time record of bridges, and there was need to systematic placement of accelerometers. The vibration acceleration time record is important during the under - bridge train crossing, about the first bridge (D201 - 00) and the vibration acceleration time domain is important during deducing the force

  20. Gas migration in KBS-3 buffer bentonite. Sensitivity of test parameters to experimental boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, J.F.; Horseman, S.T. [British Geological Survey, Nottingham (United Kingdom)

    2003-01-01

    In the current Swedish repository design concept, hydrogen gas can be generated inside a waste canister by anaerobic corrosion of the ferrous metal liner. If the gas generation rate exceeds the diffusion rate of gas molecules in the buffer porewater, gas will accumulate in the void-space of a canister until its pressure becomes large enough for it to enter the bentonite as a discrete gaseous phase. Three long tenn gas injection tests have been performed on cylinders of pre-compacted MX80 bentonite. Two of these tests were undertaken using a custom-designed constant volume and radial flow (CVRF) apparatus. Gas was injected at a centrally located porous filter installed in the clay before hydration. Arrangements were made for gas to flow to three independently monitored sink-filter arrays mounted around the specimen. Axial and radial total stresses and internal porewater pressures were continuously monitored. Breakthrough and peak gas pressures were substantially larger than the sum of the swelling pressure and the external porewater. The third test was performed. using an apparatus which radially constrains the specimen during gas flow. Observed sensitivity of the breakthrough and peak gas pressures to the test boundary conditions suggests that gas entry must be accompanied by dilation of the bentonite fabric. In other words, there is a tendency for the volume of the specimen to increase during this process. The experimental evidence is consistent with the flow of gas along a relatively small number of crack-like pathways which propagate through the clay as gas pressure increases. Gas entry and breakthrough under constant volume boundary conditions causes a substantial increase in the total stress and the internal porewater pressure. It is possible to determine the point at which gas enters the clay by monitoring changes in these parameters. Localisation of gas flow within multiple pathways results, in nonuniform discharge rates at the sinks. When gas injection

  1. Measurement of track opening contours of oblique incident 4He and 7Li-ions in CR-39: Relevance for calculation of track formation parameters

    International Nuclear Information System (INIS)

    Hermsdorf, D.; Reichelt, U.

    2010-01-01

    Solid State Nuclear Track Detectors (SSNTD) irradiated in realistic radiation fields exhibits after chemical etching very complex track images resulting from different species of particles and their energy spectra and randomly distributed angles of incidence or emission. Reading out such an etched detector surface with a light microscope, quite different track opening contours are observed. Beside the number of tracks, typically their major and minor axes are measured. In this work following problems arising from such experimental situations will be investigated: ·the measurement of track contour parameters for oblique incident 4 He and 7 Li-ions of different energies and angles in CR-39 detectors ·the theoretical description of the angular variation of both axes. ·the possibility to extract physical and spectroscopic information from major and minor track axes. This analysis is based on an intensive experimental program and the comprehensive study of theoretical models available for description of track revealing processes in CR-39.

  2. Determination of low-energy parameters of neutron-proton scattering in the the shape-parameter approximation from present-day experimental data

    International Nuclear Information System (INIS)

    Babenko, V. A.; Petrov, N. M.

    2010-01-01

    On the basis of the total cross sections for neutron-proton scattering in the region of laboratory energies below 150 keV, the value of σ 0 = 20.4288(146) b was obtained for the total cross sections for neutron-proton scattering at zero energy. This value is in very good agreement with the experimental cross sections obtained by Houke and Hurst, but it is at odds with Dilg's experimental cross section. By using the value that we found for σ 0 and the experimental values of the neutron-proton coherent scattering length f, the deuteron binding energy ε t , the deuteron effective radius ρ t (-ε t , -ε t ), and the total cross section in the region of energies below 5 MeV, the following values were found in the shape-parameter approximation for the low-energy parameters of neutron-proton scattering in the spin-triplet and spin-singlet states: a t = 5.4114(27) fm, r 0t = 1.7606(35) fm, v 2t = 0.157 fm 3 , a s = -23.7154(80) fm, r 0s = 2.706(67) fm, and v 2s = 0.491 fm 3 .

  3. Experimental Platform for measuring the parameters of magnetization of a transformer in a quasi-static transitional regime

    International Nuclear Information System (INIS)

    Milovanski, Vasil; , Blagoevgrad (Bulgaria))" data-affiliation=" (HMS “Acad. S. P. Corolov, Blagoevgrad (Bulgaria))" >Stoyanov, Krasimir; Milovanska, Stefani

    2013-01-01

    Some opportunities for development of an experimental module for magnetic research have been examined in the current paper. The goal is to attain a more accurate reading of the measured electrical signals which are directly related to the magnetic parameters and characteristics of the ferromagnetic material

  4. Technological parameter and experimental set-up influences on latch-up triggering level in bulk CMOS device

    International Nuclear Information System (INIS)

    Dubuc, J.P.; Azais, B.; Murcia, M. de

    1994-01-01

    This paper deals with experimental and simulation results on latch-up triggered by an electrical or X-rays pulse in CMOS/bulk devices. Test condition influences as well as the great importance of process parameters on latch-up immunity are emphasized. (author). 10 refs., 19 figs., 1 tab

  5. Experimental and Numerical Investigation of Design Parameters for Hydronic Embedded Thermally Active Surfaces

    DEFF Research Database (Denmark)

    Marcos-Meson, Victor; Pomianowski, Michal Zbigniew; E. Poulsen, Søren

    2015-01-01

    This paper evaluates the principal design parameters affecting the thermal performance of embedded hydronic Thermally Active Surfaces (TAS), combining the Response Surface Method (RSM) with the Finite Elements Method (FEM). The study ranks the combined effects of the parameters on the heat flux i...

  6. A study of calculation methodology and experimental measurements of the kinetic parameters for source driven subcritical systems

    International Nuclear Information System (INIS)

    Lee, Seung Min

    2009-01-01

    This work presents a theoretical study of reactor kinetics focusing on the methodology of calculation and the experimental measurements of the so-called kinetic parameters. A comparison between the methodology based on the Dulla's formalism and the classical method is made. The objective is to exhibit the dependence of the parameters on subcriticality level and perturbation. Two different slab type systems were considered: thermal one and fast one, both with homogeneous media. One group diffusion model was used for the fast reactor, and for the thermal system, two groups diffusion model, considering, in both case, only one precursor's family. The solutions were obtained using the expansion method. Also, descriptions of the main experimental methods of measurements of the kinetic parameters are presented in order to put a question about the compatibility of these methods in subcritical region. (author)

  7. Effect of nonlinear void reactivity on bifurcation characteristics of a lumped-parameter model of a BWR: A study relevant to RBMK

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Dinkar, E-mail: dinkar@iitk.ac.in [Nuclear Engineering and Technology Program, Indian Institute of Technology Kanpur, Kanpur 208 016 (India); Kalra, Manjeet Singh, E-mail: drmanjeet.singh@dituniversity.edu.in [DIT University, Dehradun 248 009 (India); Wahi, Pankaj, E-mail: wahi@iitk.ac.in [Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur 208 016 (India)

    2017-04-15

    Highlights: • A simplified model with nonlinear void reactivity feedback is studied. • Method of multiple scales for nonlinear analysis and oscillation characteristics. • Second order void reactivity dominates in determining system dynamics. • Opposing signs of linear and quadratic void reactivity enhances global safety. - Abstract: In the present work, the effect of nonlinear void reactivity on the dynamics of a simplified lumped-parameter model for a boiling water reactor (BWR) is investigated. A mathematical model of five differential equations comprising of neutronics and thermal-hydraulics encompassing the nonlinearities associated with both the reactivity feedbacks and the heat transfer process has been used. To this end, we have considered parameters relevant to RBMK for which the void reactivity is known to be nonlinear. A nonlinear analysis of the model exploiting the method of multiple time scales (MMTS) predicts the occurrence of the two types of Hopf bifurcation, namely subcritical and supercritical, leading to the evolution of limit cycles for a range of parameters. Numerical simulations have been performed to verify the analytical results obtained by MMTS. The study shows that the nonlinear reactivity has a significant influence on the system dynamics. A parametric study with varying nominal reactor power and operating conditions in coolant channel has also been performed which shows the effect of change in concerned parameter on the boundary between regions of sub- and super-critical Hopf bifurcations in the space constituted by the two coefficients of reactivities viz. the void and the Doppler coefficient of reactivities. In particular, we find that introduction of a negative quadratic term in the void reactivity feedback significantly increases the supercritical region and dominates in determining the system dynamics.

  8. Ethanol Production from Kitchen Garbage Using Zymomonas mobilis: Optimization of Parameters through Statistical Experimental Designs

    OpenAIRE

    Ma, H.; Wang, Q.; Gong, L.; Wang, X.; Yin, W.

    2008-01-01

    Plackett-Burman design was employed to screen 8 parameters for ethanol production from kitchen garbage by Zymomonas mobilis in simultaneous saccharification and fermentation. The parameters were divided into two parts, four kinds of enzymes and supplementation nutrients. The result indicated that the nutrient inside kitchen garbage could meet the requirement of ethanol production without supplementation, only protease and glucoamylase were needed to accelerate the ethanol production. The opti...

  9. Experimental Research and Mathematical Modeling of Parameters Effecting on Cutting Force and SurfaceRoughness in CNC Turning Process

    Science.gov (United States)

    Zeqiri, F.; Alkan, M.; Kaya, B.; Toros, S.

    2018-01-01

    In this paper, the effects of cutting parameters on cutting forces and surface roughness based on Taguchi experimental design method are determined. Taguchi L9 orthogonal array is used to investigate the effects of machining parameters. Optimal cutting conditions are determined using the signal/noise (S/N) ratio which is calculated by average surface roughness and cutting force. Using results of analysis, effects of parameters on both average surface roughness and cutting forces are calculated on Minitab 17 using ANOVA method. The material that was investigated is Inconel 625 steel for two cases with heat treatment and without heat treatment. The predicted and calculated values with measurement are very close to each other. Confirmation test of results showed that the Taguchi method was very successful in the optimization of machining parameters for maximum surface roughness and cutting forces in the CNC turning process.

  10. Changes of the more relevant PHTS parameters after the cleaning of the steam generators primary side at Embalse nuclear power plant

    International Nuclear Information System (INIS)

    Moreno, Carlos A.; Coutsiers, Ernesto; Acevedo, Paul; Pomerantz, Marcelo E.

    2003-01-01

    During the operation of the plant magnetite deposition occurs at the inner walls of Primary Heat Transport System (PHTS). This deposition is particularly significant at the U-tubes of steam generators. The consequence of this is the deterioration of heat transfer to the Secondary System. In order to minimize this impact, during the annual outage of 2000, the steam generators primary side cleaning by the SIVABLAST technique was carried out. This technique consists in blasting the inner walls with tiny stainless steel balls propelled by air at high pressure. This paper presents the change of the more relevant parameters of PHTS after that cleaning. The parameters analyzed and the main results are the following: 1) Inlet header temperature dropped 4.7 C degrees at full power; 2) Exit quality at the outlet headers decreased from 3,5% to 1,5%; 3) Global PHTS flow in single phase evaluated from: a) In-site instrumentation increased 4,6%; b) Thermalhydraulic code NUCIRC 1.0 increased 3,2%; c) measured flows at the instrumented fuel channels increased 4.4%. (author)

  11. Experimental and computational correlation of fracture parameters KIc, JIc, and GIc for unimodular and bimodular graphite components

    Science.gov (United States)

    Bhushan, Awani; Panda, S. K.

    2018-05-01

    The influence of bimodularity (different stress ∼ strain behaviour in tension and compression) on fracture behaviour of graphite specimens has been studied with fracture toughness (KIc), critical J-integral (JIc) and critical strain energy release rate (GIc) as the characterizing parameter. Bimodularity index (ratio of tensile Young's modulus to compression Young's modulus) of graphite specimens has been obtained from the normalized test data of tensile and compression experimentation. Single edge notch bend (SENB) testing of pre-cracked specimens from the same lot have been carried out as per ASTM standard D7779-11 to determine the peak load and critical fracture parameters KIc, GIc and JIc using digital image correlation technology of crack opening displacements. Weibull weakest link theory has been used to evaluate the mean peak load, Weibull modulus and goodness of fit employing two parameter least square method (LIN2), biased (MLE2-B) and unbiased (MLE2-U) maximum likelihood estimator. The stress dependent elasticity problem of three-dimensional crack progression behaviour for the bimodular graphite components has been solved as an iterative finite element procedure. The crack characterizing parameters critical stress intensity factor and critical strain energy release rate have been estimated with the help of Weibull distribution plot between peak loads versus cumulative probability of failure. Experimental and Computational fracture parameters have been compared qualitatively to describe the significance of bimodularity. The bimodular influence on fracture behaviour of SENB graphite has been reflected on the experimental evaluation of GIc values only, which has been found to be different from the calculated JIc values. Numerical evaluation of bimodular 3D J-integral value is found to be close to the GIc value whereas the unimodular 3D J-value is nearer to the JIc value. The significant difference between the unimodular JIc and bimodular GIc indicates that

  12. Comparison of different morphological parameters with duration of obstruction created experimentally in unilateral upper ureters: an animal model.

    Science.gov (United States)

    Panda, Shasanka Shekhar; Bajpai, Minu; Mallick, Saumyaranjan; Sharma, Mehar C

    2014-01-01

    The objective of the following study is to determine and to compare the different morphological parameters with duration of obstruction created experimentally in unilateral upper ureters of rats. Unilateral upper ureteric obstruction was created in 60 adult Wistar rats that were reversed after predetermined intervals. Rats were sacrificed and ipsilateral kidneys were subjected for analysis of morphological parameters such as renal height, cranio-caudal diameter, antero-posterior diameter, lateral diameter, volume of the pelvis and average cortical thickness: Renal height. Renal height and cranio-caudal diameter of renal pelvis after ipsilateral upper ureteric obstruction started rising as early as 7 days of creating obstruction and were affected earlier than antero-posterior and lateral diameter and also were reversed earlier than other parameters after reversal of obstruction. Renal cortical thickness and volume of the pelvis were affected after prolonged obstruction (> 3 weeks) and were the late parameters to be reversed after reversal of obstruction. Cranio-caudal diameter and renal height were the early morphological parameters to be affected and reversed after reversal of obstruction in experimentally created ipsilateral upper ureteric obstruction.

  13. Comparison of different morphological parameters with duration of obstruction created experimentally in unilateral upper ureters: An animal model

    Directory of Open Access Journals (Sweden)

    Shasanka Shekhar Panda

    2014-01-01

    Full Text Available Background: The objective of the following study is to determine and to compare the different morphological parameters with duration of obstruction created experimentally in unilateral upper ureters of rats. Materials and Methods: Unilateral upper ureteric obstruction was created in 60 adult Wistar rats that were reversed after predetermined intervals. Rats were sacrificed and ipsilateral kidneys were subjected for analysis of morphological parameters such as renal height, cranio-caudal diameter, antero-posterior diameter, lateral diameter, volume of the pelvis and average cortical thickness: Renal height. Results: Renal height and cranio-caudal diameter of renal pelvis after ipsilateral upper ureteric obstruction started rising as early as 7 days of creating obstruction and were affected earlier than antero-posterior and lateral diameter and also were reversed earlier than other parameters after reversal of obstruction. Renal cortical thickness and volume of the pelvis were affected after prolonged obstruction (> 3 weeks and were the late parameters to be reversed after reversal of obstruction. Conclusions: Cranio-caudal diameter and renal height were the early morphological parameters to be affected and reversed after reversal of obstruction in experimentally created ipsilateral upper ureteric obstruction.

  14. Experimental design approach to the process parameter optimization for laser welding of martensitic stainless steels in a constrained overlap configuration

    Science.gov (United States)

    Khan, M. M. A.; Romoli, L.; Fiaschi, M.; Dini, G.; Sarri, F.

    2011-02-01

    This paper presents an experimental design approach to process parameter optimization for the laser welding of martensitic AISI 416 and AISI 440FSe stainless steels in a constrained overlap configuration in which outer shell was 0.55 mm thick. To determine the optimal laser-welding parameters, a set of mathematical models were developed relating welding parameters to each of the weld characteristics. These were validated both statistically and experimentally. The quality criteria set for the weld to determine optimal parameters were the minimization of weld width and the maximization of weld penetration depth, resistance length and shearing force. Laser power and welding speed in the range 855-930 W and 4.50-4.65 m/min, respectively, with a fiber diameter of 300 μm were identified as the optimal set of process parameters. However, the laser power and welding speed can be reduced to 800-840 W and increased to 4.75-5.37 m/min, respectively, to obtain stronger and better welds.

  15. Model of twelve properties of a set of organic solvents with graph-theoretical and/or experimental parameters.

    Science.gov (United States)

    Pogliani, Lionello

    2010-01-30

    Twelve properties of a highly heterogeneous class of organic solvents have been modeled with a graph-theoretical molecular connectivity modified (MC) method, which allows to encode the core electrons and the hydrogen atoms. The graph-theoretical method uses the concepts of simple, general, and complete graphs, where these last types of graphs are used to encode the core electrons. The hydrogen atoms have been encoded by the aid of a graph-theoretical perturbation parameter, which contributes to the definition of the valence delta, delta(v), a key parameter in molecular connectivity studies. The model of the twelve properties done with a stepwise search algorithm is always satisfactory, and it allows to check the influence of the hydrogen content of the solvent molecules on the choice of the type of descriptor. A similar argument holds for the influence of the halogen atoms on the type of core electron representation. In some cases the molar mass, and in a minor way, special "ad hoc" parameters have been used to improve the model. A very good model of the surface tension could be obtained by the aid of five experimental parameters. A mixed model method based on experimental parameters plus molecular connectivity indices achieved, instead, to consistently improve the model quality of five properties. To underline is the importance of the boiling point temperatures as descriptors in these last two model methodologies. Copyright 2009 Wiley Periodicals, Inc.

  16. Do means-end chains exist? Experimental tests of their hierarchicity, automatic spreading activation, directionality, and self-relevance

    DEFF Research Database (Denmark)

    Scholderer, Joachim; Grunert, Klaus G.

    2004-01-01

    , bidirectionality, and self-relevance. The predictions were tested in altogether six experiments, using the same basic methodology. Two sessions were held with each participant. In a pilot session, a set of conventional MEC representations was elicited from each participant using the laddering technique. From......Despite its popularity in consumer research, means-end chain (MEC) theory suffers from problems of unconfirmed validity. Theoretically, MECs can be cast as associative networks with a three-layered structure that should exhibit four properties: hierarchicity, automatic spreading activation...

  17. The combined theoretical and experimental approach to arrive at optimum parameters in friction stir welding

    Science.gov (United States)

    Jagadeesha, C. B.

    2017-12-01

    Even though friction stir welding was invented long back (1991) by TWI England, till now there has no method or procedure or approach developed, which helps to obtain quickly optimum or exact parameters yielding good or sound weld. An approach has developed in which an equation has been derived, by which approximate rpm can be obtained and by setting range of rpm ±100 or 50 rpm over approximate rpm and by setting welding speed equal to 60 mm/min or 50 mm/min one can conduct FSW experiment to reach optimum parameters; one can reach quickly to optimum parameters, i.e. desired rpm, and welding speed, which yield sound weld by the approach. This approach can be effectively used to obtain sound welds for all similar and dissimilar combinations of materials such as Steel, Al, Mg, Ti, etc.

  18. Experimental study and process parameters analysis on the vacuum cooling of iceberg lettuce

    International Nuclear Information System (INIS)

    He Suyan; Li Yunfei

    2008-01-01

    The vacuum cooling of iceberg lettuce was described in this paper. Based on the energy and mass balance, a mathematical model was developed to analyze the performance of the vacuum cooler and the evaporation-boiling phenomena during vacuum cooling of iceberg lettuce. The temporal trends of total system pressure, produce temperature such as surface temperature, center temperature, mass-average temperature, the weight loss of iceberg lettuce during vacuum cooling were predicted. Validation experimentation is achieved in the designed vacuum cooler. The experimental data were compared with the simulation results. It was found that the differences of the temperature between the simulation and the experiments were within 1 deg. C. The amount of water evaporated from the iceberg lettuce by simulation was 3.32% during the whole vacuum cooling, while the tested water loss rate was 2.97%, the maximal deviation of weight loss was within 0.59%. The simulation results agreed well with the experimental data

  19. Experimental study and process parameters analysis on the vacuum cooling of iceberg lettuce

    Energy Technology Data Exchange (ETDEWEB)

    He Suyan [School of Mechanical and Electrical Engineering, Qingdao University, Qingdao 266071 (China)], E-mail: hesuyan67829@sina.com; Li Yunfei [Department of Food Science and Engineering, School of Agriculture and Biology, Shanghai Jiao Tong University (China)

    2008-10-15

    The vacuum cooling of iceberg lettuce was described in this paper. Based on the energy and mass balance, a mathematical model was developed to analyze the performance of the vacuum cooler and the evaporation-boiling phenomena during vacuum cooling of iceberg lettuce. The temporal trends of total system pressure, produce temperature such as surface temperature, center temperature, mass-average temperature, the weight loss of iceberg lettuce during vacuum cooling were predicted. Validation experimentation is achieved in the designed vacuum cooler. The experimental data were compared with the simulation results. It was found that the differences of the temperature between the simulation and the experiments were within 1 deg. C. The amount of water evaporated from the iceberg lettuce by simulation was 3.32% during the whole vacuum cooling, while the tested water loss rate was 2.97%, the maximal deviation of weight loss was within 0.59%. The simulation results agreed well with the experimental data.

  20. Experimental investigation of a draft tube spouted bed for effects of geometric parameters on operation

    DEFF Research Database (Denmark)

    Azizaddini, Seyednezamaddin; Lin, Weigang; Dam-Johansen, Kim

    2016-01-01

    Experiments are performed in a draft tube spouted bed (DTSB) to investigate effects of the operating conditions and the geometric parameters on the hydrodynamics. Geometry parameters, such as heights of the entrained zone, draft tube inner diameter, inner angle of the conical section were studied....... Increasing the draft tube inner diameter, sharper inner angle of the conical section and higher height of entrained zone increase the internal solid circulation rate and the pressure drop. Even though, for all different configurations, higher gas feeding rate leads to higher internal solid circulation rate...

  1. Experimental studies of keV energy neutron-induced reactions relevant to astrophysics and nuclear physics

    Energy Technology Data Exchange (ETDEWEB)

    Shima, T.; Kii, T.; Kikuchi, T.; Okazaki, F.; Kobayashi, T.; Baba, T.; Nagai, Y. [Tokyo Inst. of Tech. (Japan). Faculty of Science; Igashira, M.

    1997-03-01

    Nuclear reactions induced by keV energy neutrons provide a plenty of informations for studies of both astrophysics and nuclear physics. In this paper we will show our experimental studies of neutron- induced reactions of light nuclei in the keV energy region by means of a pulsed keV neutron beam and high-sensitivity detectors. Also we will discuss astrophysical and nuclear-physical consequences by using the obtained results. (author)

  2. Residual waters treatment by heterogeneous photocatalysis: a study of experimental parameters applied to the photoelectrocatalysis

    Directory of Open Access Journals (Sweden)

    Henrique de Santana

    2006-02-01

    Full Text Available In this paper, the use of electrochemically-assisted heterogeneous photo-catalysis will be discussed. Several operational parameters will also be discussed, in order to achieve optimum efficiency of this photo-degradation system, such as: the influence of variables as support electrolyte, applied potential, dye initial concentration, pH and choice of a UV source on dye degradation.

  3. Experimental study of some homeostatic parameters at late times after exposure to radiation

    International Nuclear Information System (INIS)

    Chertkov, K.S.; Andrianova, I.E.; Atamanova, O.M.; Filimonova, G.I.; Nesterova, T.A.; Sbitneva, M.F.; Glushkov, V.A.; Chotij, V.G.; Stejmatskaya, Z.A.

    1994-01-01

    Following radiation damage from LD 50 - LD 97 , changes in blood, immune and endocrine parameters were revealed and followed up in dogs at the time of late effects development, 3-18 months after exposure. The changes result from post-radiation immunodeficiency and resemble those observed in residents of radioactive contaminate areas or in men participated in Chernobyl accident amelioration

  4. Experimental parameter study for passive vortex generators on a 30% thick airfoil

    NARCIS (Netherlands)

    Baldacchino, D.; Simao Ferreira, C.; De Tavernier, D.A.M.; Timmer, W.A.; van Bussel, G.J.W.

    2018-01-01

    Passive vane-type vortex generators (VGs) are commonly used on wind turbine blades to mitigate the effects of flow separation. However, significant uncertainty surrounds VG design guidelines. Understanding the influence of VG parameters on airfoil performance requires a systematic approach

  5. Experimental study on two-phase flow parameters of subcooled boiling in inclined annulus

    International Nuclear Information System (INIS)

    Lee, Tae Ho; Kim, Moon Oh; Park, Goon Cherl

    1999-01-01

    Local two-phase flow parameters of subcooled flow boiling in inclined annulus were measured to investigate the effect of inclination on the internal flow structure. Two-conductivity probe technique was applied to measured local gas phasic parameters, including void by fraction, vapor bubble frequency, chord length, vapor bubble velocity and interfacial area concentration. Local liquid velocity was measured by Pitot tube. Experiments were conducted for three angles of inclination: 0 o (vertical), 30 o , 60 o . The system pressure was maintained at atmospheric pressure. The range of average void fraction was up to 10 percent and the average liquid superficial velocities were less than 1.3 m/sec. The results of experiments showed that the distributions of two-phase flow parameters were influenced by the angle of channel inclination. Especially, the void fraction and chord length distributions were strongly affected by the increase of inclination angle, and flow pattern transition to slug flow was observed depending on the flow conditions. The profiles of vapor velocity, liquid velocity and interfacial area concentration were found to be affected by the non-symmetric bubble size distribution in inclined channel. Using the measured distributions of local phasic parameters, an analysis for predicting average void fraction was performed based on the drift flux model and flowing volumetric concentration. And it was demonstrated that the average void fraction can be more appropriately presented in terms of flowing volumetric concentration. (Author). 18 refs., 2 tabs., 18 figs

  6. Experimentally-based optimization of contact parameters in dynamics simulation of humanoid robots

    NARCIS (Netherlands)

    Vivian, Michele; Reggiani, Monica; Sartori, Massimo

    2013-01-01

    With this work we introduce a novel methodology for the simulation of walking of a humanoid robot. Motion capture technology is used to calibrate the dynamics engine internal parameters and validate the simulated motor task. Results showed the calibrated contact model allows predicting dynamically

  7. Determination of the physical parameters distribution in spin transition compounds using experimental FORC diagram

    International Nuclear Information System (INIS)

    Tanasa, Radu; Linares, Jorge; Enachescu, Cristian; Varret, Francois; Stancu, Alexandru

    2006-01-01

    Spin transitions materials are characterized with an innovative experimental method, i.e. first-order reversal curve (FORC) diagram. The interpretation of the results is performed in the framework of two different Ising-like models: a mean-field approach and the exact solution done by the Monte Carlo entropic sampling (MCES) method

  8. Construction of an experimental simplified model for determining of flow parameters in chemical reactors, using nuclear techniques

    International Nuclear Information System (INIS)

    Araujo Paiva, J.A. de.

    1981-03-01

    The development of a simplified experimental model for investigation of nuclear techniques to determine the solid phase parameters in gas-solid flows is presented. A method for the measurement of the solid phase residence time inside a chemical reactor of the type utilised in the cracking process of catalytic fluids is described. An appropriate radioactive labelling technique of the solid phase and the construction of an eletronic timing circuit were the principal stages in the definition of measurement technique. (Author) [pt

  9. Experimental design for parameter estimation of two time-scale model of photosynthesis and photoinhibition in microalgae

    Czech Academy of Sciences Publication Activity Database

    Papáček, Š.; Čelikovský, Sergej; Rehák, Branislav; Štys, D.

    2010-01-01

    Roč. 80, č. 6 (2010), s. 1302-1309 ISSN 0378-4754 R&D Projects: GA ČR(CZ) GA102/08/0186 Institutional research plan: CEZ:AV0Z10750506 Keywords : Photosynthetic factory * Experimental design * Parameter estimation * Two-scale modeling Subject RIV: BC - Control Systems Theory Impact factor: 0.812, year: 2010 http://library.utia.cas.cz/separaty/2010/TR/celikovsky-0341543.pdf

  10. An optimal generic model for multi-parameters and big data optimizing: a laboratory experimental study

    Science.gov (United States)

    Utama, D. N.; Ani, N.; Iqbal, M. M.

    2018-03-01

    Optimization is a process for finding parameter (parameters) that is (are) able to deliver an optimal value for an objective function. Seeking an optimal generic model for optimizing is a computer science study that has been being practically conducted by numerous researchers. Generic model is a model that can be technically operated to solve any varieties of optimization problem. By using an object-oriented method, the generic model for optimizing was constructed. Moreover, two types of optimization method, simulated-annealing and hill-climbing, were functioned in constructing the model and compared to find the most optimal one then. The result said that both methods gave the same result for a value of objective function and the hill-climbing based model consumed the shortest running time.

  11. Experimental investigation on local parameter measurement using optical probes in two-phase flow under rolling condition

    International Nuclear Information System (INIS)

    Tian Daogui; Sun Licheng; Yan Changqi; Liu Guoqiang

    2013-01-01

    In order to get more local interfacial information as well as to further comprehend the intrinsic mechanism of two-phase flow under rolling condition, a method was proposed to measure the local parameters by using optical probes under rolling condition in this paper. An experimental investigation of two-phase flow under rolling condition was conducted using the probe fabricated by the authors. It is verified that the probe method is feasible to measure the local parameters in two'-phase flow under rolling condition. The results show that the interfacial parameters distribution near wall region has a distinct periodicity due to the rolling motion. The averaged deviation of the void fraction measured by the probe from that obtained from measured pressure drop is about 8%. (authors)

  12. Experimental determination of the dimensionless scaling parameter of energy transport in tokamaks

    International Nuclear Information System (INIS)

    Luce, T.C.; Petty, C.C.

    1995-07-01

    Controlled fusion experiments have focused on the variation of the plasma characteristics as the engineering or control parameters are systematically changed. This has led to the development of extrapolation formulae for prediction of future device performance using these same variables as a basis. Recently, it was noticed that present-day tokamaks can operate with all of the dimensionless variables which appear in the Vlasov-Maxwell system of equations at values projected for a fusion powerplant with the exception of the parameter ρ * , the gyroradius normalized to the machine size. The scaling with this parameter is related to the benefit of increasing the size of the machine either directly or effectively by increasing the magnetic field. It is exactly this scaling which is subject to systematic error in the inter-machine databases and the cost driver for any future machine. If this scaling can be fixed by a series of single machine experiments, much as the current and power scalings have been, the confidence in the prediction of future device performance would be greatly enhanced. While carrying out experiments of this type, it was also found that the ρ * scaling can illuminate the underlying physics of energy transport. Conclusions drawn from experiments on the DIII-D tokamak in these two areas are the subject of this paper

  13. CFD and experimental investigation of sloshing parameters for the safety assessment of HLM reactors

    Energy Technology Data Exchange (ETDEWEB)

    Myrillas, Konstantinos, E-mail: myrillas@vki.ac.be [von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640 Rhode-St-Genèse (Belgium); Planquart, Philippe, E-mail: philippe.planquart@vki.ac.be [von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640 Rhode-St-Genèse (Belgium); Simonini, Alessia, E-mail: Simonini@vki.ac.be [von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640 Rhode-St-Genèse (Belgium); Buchlin, Jean-Marie, E-mail: buchlin@vki.ac.be [von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640 Rhode-St-Genèse (Belgium); Schyns, Marc, E-mail: mschyns@SCKCEN.BE [SCK-CEN, Boeretang 200, B-2400 Mol (Belgium)

    2017-02-15

    Highlights: • Comparison of sloshing behavior in cylindrical tank using mercury and water. • Flow visualization of liquid sloshing in resonance case. • CFD simulations of sloshing with OpenFOAM, using the VOF method. • Qualitative and quantitative comparison of experimental and numerical results. • Evaluation of sloshing forces on the tank walls from numerical simulations. - Abstract: For the safety assessment of Heavy Liquid Metal nuclear reactors under seismic excitation, sloshing phenomena can be of great concern. The earthquake motions are transferred to the liquid coolant which oscillates inside the vessel, exerting additional forces on the walls and internal structures. The present study examines the case of MYRRHA, a multi-purpose experimental reactor with LBE as coolant, developed by SCK·CEN. The sloshing behavior of liquid metals is studied through a comparison between mercury and water in a cylindrical tank. Experimental investigation of sloshing is carried out using optical techniques with the shaking table facility SHAKESPEARE at the von Karman Institute. Emphasis is given on the resonance case, where maximum forces occur on the tank walls. The experimental cases are reproduced numerically with the CFD software OpenFOAM, using the VOF method to track the liquid interface. The non-linear nature of sloshing is observed through visualization, where swirling is shown in the resonance case. The complex behavior is well reproduced by the CFD simulations, providing good qualitative validation of the numerical tools. A quantitative comparison of the maximum liquid elevation inside the tank shows higher values for the liquid metal than for water. Some discrepancies are revealed in CFD results and the differences are quantified. From simulations it is verified that the forces scale with the density ratio, following similar evolution in time. Overall, water is demonstrated to be a valid option as a working liquid in order to evaluate the sloshing

  14. CFD and experimental investigation of sloshing parameters for the safety assessment of HLM reactors

    International Nuclear Information System (INIS)

    Myrillas, Konstantinos; Planquart, Philippe; Simonini, Alessia; Buchlin, Jean-Marie; Schyns, Marc

    2017-01-01

    Highlights: • Comparison of sloshing behavior in cylindrical tank using mercury and water. • Flow visualization of liquid sloshing in resonance case. • CFD simulations of sloshing with OpenFOAM, using the VOF method. • Qualitative and quantitative comparison of experimental and numerical results. • Evaluation of sloshing forces on the tank walls from numerical simulations. - Abstract: For the safety assessment of Heavy Liquid Metal nuclear reactors under seismic excitation, sloshing phenomena can be of great concern. The earthquake motions are transferred to the liquid coolant which oscillates inside the vessel, exerting additional forces on the walls and internal structures. The present study examines the case of MYRRHA, a multi-purpose experimental reactor with LBE as coolant, developed by SCK·CEN. The sloshing behavior of liquid metals is studied through a comparison between mercury and water in a cylindrical tank. Experimental investigation of sloshing is carried out using optical techniques with the shaking table facility SHAKESPEARE at the von Karman Institute. Emphasis is given on the resonance case, where maximum forces occur on the tank walls. The experimental cases are reproduced numerically with the CFD software OpenFOAM, using the VOF method to track the liquid interface. The non-linear nature of sloshing is observed through visualization, where swirling is shown in the resonance case. The complex behavior is well reproduced by the CFD simulations, providing good qualitative validation of the numerical tools. A quantitative comparison of the maximum liquid elevation inside the tank shows higher values for the liquid metal than for water. Some discrepancies are revealed in CFD results and the differences are quantified. From simulations it is verified that the forces scale with the density ratio, following similar evolution in time. Overall, water is demonstrated to be a valid option as a working liquid in order to evaluate the sloshing

  15. Experimental study and process parameters analysis on the vacuum cooling of iceberg lettuce

    Energy Technology Data Exchange (ETDEWEB)

    He, Su-Yan [School of Mechanical and Electrical Engineering, Qingdao University, Qingdao 266071 (China); Li, Yun-Fei [Department of Food Science and Engineering, School of Agriculture and Biology, Shanghai Jiao Tong University (China)

    2008-10-15

    The vacuum cooling of iceberg lettuce was described in this paper. Based on the energy and mass balance, a mathematical model was developed to analyze the performance of the vacuum cooler and the evaporation-boiling phenomena during vacuum cooling of iceberg lettuce. The temporal trends of total system pressure, produce temperature such as surface temperature, center temperature, mass-average temperature, the weight loss of iceberg lettuce during vacuum cooling were predicted. Validation experimentation is achieved in the designed vacuum cooler. The experimental data were compared with the simulation results. It was found that the differences of the temperature between the simulation and the experiments were within 1{sup o}C. The amount of water evaporated from the iceberg lettuce by simulation was 3.32% during the whole vacuum cooling, while the tested water loss rate was 2.97%, the maximal deviation of weight loss was within 0.59%. The simulation results agreed well with the experimental data. (author)

  16. Study of Parameters Effect on Hydrodynamics of a Gas-Solid Chamber Experimentally and Numerically

    Directory of Open Access Journals (Sweden)

    Rahimzadeh Hassan

    2012-04-01

    Full Text Available In this research, gas velocity, initial static bed height and particle size effect on hydrodynamics of a non-reactive gas–solid fluidized bed chamber were studied experimentally and computationally. A multi fluid Eulerian model incorporating the kinetic theory for solid particles was applied to simulate the unsteady state behavior of this chamber and momentum exchange coefficients were calculated by using the Syamlal- O’Brien drag functions. Simulation results were compared with the experimental data in order to validate the CFD model. Pressure drops predicted by the simulations at different particle sizes and initial static bed height were in good agreement with experimental measurements at superficial gas velocity higher than the minimum fluidization velocity. Simulation results also indicated that small bubbles were produced at the bottom of the bed. These bubbles collided with each other as they moved upwards forming larger bubbles. Furthermore, this comparison showed that the model can predict hydrodynamic behavior of gas solid fluidized bed chambers reasonably well.

  17. A constitutive model for the thermo-mechanical behaviour of fusion-relevant pebble beds and its application to the simulation of HELICA mock-up experimental results

    International Nuclear Information System (INIS)

    Vella, G.; Maio, P.A. Di; Giammusso, R.; Tincani, A.; Orco, G. Dell

    2006-01-01

    Within the framework of the activities promoted by European Fusion Development Agreement on the technology of the Helium Cooled Pebble Bed Test Blanket Module to be irradiated in one of the ITER equatorial ports, attention has been focused on the theoretical modelling of the thermo-mechanical constitutive behaviour of both beryllium and lithiated ceramics pebble beds, that are envisaged to act respectively as neutron multiplier and tritium breeder. The thermo-mechanical behaviour of the pebble beds and their nuclear performances in terms of tritium production depend on the reactor relevant conditions (heat flux and neutron wall load), the pebble sizes and the breeder cell geometries (bed thickness, pebble packing factor, bed overall thermal conductivity). ENEA-Brasimone and the Department of Nuclear Engineering (DIN) of the Palermo University have performed intense research activities intended to investigate fusion-relevant pebble bed thermo-mechanical behaviour by adopting both experimental and theoretical approaches. In particular, ENEA has carried out several experimental campaigns on small scale mock-ups tested in out-of-pile conditions, while DIN has developed a proper constitutive model that has been implemented on commercial FEM code, for the prediction of the thermal and mechanical performances of fusion-relevant pebble beds and for the comparison with the experimental results of the ENEA tests. In that framework, HELICA mock-up has been set-up and tested to investigate the behaviour of pebble bed in reactor-relevant geometries, providing useful data sets to be numerically reproduced by means of the DIN constitutive model, contributing to its assessment. The paper presents the constitutive model developed and the main experimental results of two test campaigns on HELICA mock-up carried out at HE-FUS 3 facility of ENEA Brasimone, the geometry of the mock-up, the adopted thermal and mechanical boundary conditions and the test operating conditions. The most

  18. Experimental Analysis of the Input Variables’ Relevance to Forecast Next Day’s Aggregated Electric Demand Using Neural Networks

    Directory of Open Access Journals (Sweden)

    Pablo García

    2013-06-01

    Full Text Available Thanks to the built in intelligence (deployment of new intelligent devices and sensors in places where historically they were not present, the Smart Grid and Microgrid paradigms are able to take advantage from aggregated load forecasting, which opens the door for the implementation of new algorithms to seize this information for optimization and advanced planning. Therefore, accuracy in load forecasts will potentially have a big impact on key operation factors for the future Smart Grid/Microgrid-based energy network like user satisfaction and resource saving, and new methods to achieve an efficient prediction in future energy landscapes (very different from the centralized, big area networks studied so far. This paper proposes different improved models to forecast next day’s aggregated load using artificial neural networks, taking into account the variables that are most relevant for the aggregated. In particular, seven models based on the multilayer perceptron will be proposed, progressively adding input variables after analyzing the influence of climate factors on aggregated load. The results section presents the forecast from the proposed models, obtained from real data.

  19. Recent experimental results on ICF target implosions by Z-pinch radiation sources and their relevance to ICF ignition studies

    International Nuclear Information System (INIS)

    Mehlhorn, T A; Bailey, J E; Bennett, G; Chandler, G A; Cooper, G; Cuneo, M E; Golovkin, I; Hanson, D L; Leeper, R J; MacFarlane, J J; Mancini, R C; Matzen, M K; Nash, T J; Olson, C L; Porter, J L; Ruiz, C L; Schroen, D G; Slutz, S A; Varnum, W; Vesey, R A

    2003-01-01

    Inertial confinement fusion capsule implosions absorbing up to 35 kJ of x-rays from a ∼220 eV dynamic hohlraum on the Z accelerator at Sandia National Laboratories have produced thermonuclear D-D neutron yields of (2.6±1.3) x 10 10 . Argon spectra confirm a hot fuel with T e ∼ 1 keV and n e ∼ (1-2) x 10 23 cm -3 . Higher performance implosions will require radiation symmetry control improvements. Capsule implosions in a ∼70 eV double-Z-pinch-driven secondary hohlraum have been radiographed by 6.7 keV x-rays produced by the Z-beamlet laser (ZBL), demonstrating a drive symmetry of about 3% and control of P 2 radiation asymmetries to ±2%. Hemispherical capsule implosions have also been radiographed in Z in preparation for future experiments in fast ignition physics. Z-pinch-driven inertial fusion energy concepts are being developed. The refurbished Z machine (ZR) will begin providing scaling information on capsule and Z-pinch in 2006. The addition of a short pulse capability to ZBL will enable research into fast ignition physics in the combination of ZR and ZBL-petawatt. ZR could provide a test bed to study NIF-relevant double-shell ignition concepts using dynamic hohlraums and advanced symmetry control techniques in the double-pinch hohlraum backlit by ZBL

  20. Recent experimental results on ICF target implosions by Z-pinch radiation sources and their relevance to ICF ignition studies

    International Nuclear Information System (INIS)

    Bailey, James E.; Chandler, Gordon Andrew; Vesey, Roger Alan; Hanson, David Lester; Olson, Craig Lee; Nash, Thomas J.; Matzen, Maurice Keith; Ruiz, Carlos L.; Porter, John Larry Jr.; Cuneo, Michael Edward; Varnum, William S.; Bennett, Guy R.; Cooper, Gary Wayne; Schroen, Diana Grace; Slutz, Stephen A.; MacFarlane, Joseph John; Leeper, Ramon Joe; Golovkin, I.E.; Mehlhorn, Thomas Alan; Mancini, Roberto Claudio

    2003-01-01

    Inertial confinement fusion capsule implosions absorbing up to 35 kJ of x-rays from a ∼220 eV dynamic hohlraum on the Z accelerator at Sandia National Laboratories have produced thermonuclear D-D neutron yields of (2.6 ± 1.3) x 10 10 . Argon spectra confirm a hot fuel with Te ∼ 1 keV and n e ∼ (1-2) x 10 23 cm -3 . Higher performance implosions will require radiation symmetry control improvements. Capsule implosions in a ∼70 eV double-Z-pinch-driven secondary hohlraum have been radiographed by 6.7 keV x-rays produced by the Z-beamlet laser (ZBL), demonstrating a drive symmetry of about 3% and control of P 2 radiation asymmetries to ±2%. Hemispherical capsule implosions have also been radiographed in Z in preparation for future experiments in fast ignition physics. Z-pinch-driven inertial fusion energy concepts are being developed. The refurbished Z machine (ZR) will begin providing scaling information on capsule and Z-pinch in 2006. The addition of a short pulse capability to ZBL will enable research into fast ignition physics in the combination of ZR and ZBL-petawatt. ZR could provide a test bed to study NIF-relevant double-shell ignition concepts using dynamic hohlraums and advanced symmetry control techniques in the double-pinch hohlraum backlit by ZBL.

  1. Laboratory testing of waste glass aqueous corrosion; effects of experimental parameters

    International Nuclear Information System (INIS)

    Ebert, W.L.; Mazer, J.J.

    1993-01-01

    A literature survey has been performed to assess the effects of the temperature, glass surface area/leachate volume ratio, leachant composition, leachant flow rate, and glass composition (actual radioactive vs. simulated glass) used in laboratory tests on the measured glass reaction rate. The effects of these parameters must be accounted for in mechanistic models used to project glass durability over long times. Test parameters can also be utilized to highlight particular processes in laboratory tests. Waste glass corrosion results as water diffusion, ion-exchange, and hydrolysis reactions occur simultaneously to devitrify the glass and release soluble glass components into solution. The rates of these processes are interrelated by the affects of the solution chemistry and glass alteration phases on each process, and the dominant (fastest) process may change as the reaction progresses. Transport of components from the release sites into solution may also affect the observed corrosion rate. The reaction temperature will affect the rate of each process, while other parameters will affect the solution chemistry and which processes are observed during the test. The early stages of corrosion will be observed under test conditions which maintain dilute leachates and the later stages will be observed under conditions that generate more concentrated leachate solutions. Typically, water diffusion and ion-exchange reactions dominate the observed glass corrosion in dilute solutions while hydrolysis reactions dominant in more concentrated solutions. Which process(es) controls the long-term glass corrosion is not fully understood, and the long-term corrosion rate may be either transport- or reaction-limited

  2. Wire Array Z-pinches on Sphinx Machine: Experimental Results and Relevant Points of Microsecond Implosion Physics

    Science.gov (United States)

    Calamy, H.; Hamann, F.; Lassalle, F.; Bayol, F.; Mangeant, C.; Morell, A.; Huet, D.; Bedoch, J. P.; Chittenden, J. P.; Lebedev, S. V.; Jennings, C. A.; Bland, S. N.

    2006-01-01

    Centre d'Etudes de Gramat (France) has developed an efficient long implosion time (800 ns) Aluminum plasma radiation source (PRS). Based on the LTD technology, the SPHINX facility is developed as a 1-3MJ, 1μs rise time, 4-10 MA current driver. In this paper, it was used in 1MJ, 4MA configuration to drive Aluminum nested wire arrays Z-pinches with K-shell yield up to 20 kJ and a FWHM of the x-ray pulse of about 50 ns. We present latest SPHINX experiments and some of the main physic issues of the microsecond regime. Experimental setup and results are described with the aim of giving trends that have been obtained. The main features of microsecond implosion of wire arrays can be analyzed thanks to same methods and theories as used for faster Z-pinches. The effect of load polarity was examined. The stability of the implosion , one of the critical point of microsecond wire arrays due to the load dimensions imposed by the time scale, is tackled. A simple scaling from 100 ns Z-pinch results to 800 ns ones gives good results and the use of nested arrays improves dramatically the implosion quality and the Kshell yield of the load. However, additional effects such as the impact of the return current can geometry on the implosion have to be taken into account on our loads. Axial inhomogeneity of the implosion the origin of which is not yet well understood occurs in some shots and impacts the radiation output. The shape of the radiative pulse is discussed and compared with the homogeneity of the implosion. Numerical 2D R-Z and R-θ simulations are used to highlight some experimental results and understand the plasma conditions during these microsecond wire arrays implosions.

  3. An experimental investigation of stimulated Brillouin scattering in laser-produced plasmas relevant to inertial confinement fusion

    International Nuclear Information System (INIS)

    Bradley, K.S.

    1993-01-01

    Despite the apparent simplicity of controlled fusion, there are many phenomena which have prevented its achievement. One phenomenon is laser-plasma instabilities. An investigation of one such instability, stimulated Brillouin scattering (SBS), is reported here. SBS is a parametric process whereby an electromagnetic wave (the parent wave) decays into another electromagnetic wave and an ion acoustic wave (the daughter waves). SBS impedes controlled fusion since it can scatter much or all of the incident laser light, resulting in poor drive symmetry and inefficient laser-plasma coupling. It is widely believed that SBS becomes convectively unstable--that is, it grows as it traverses the plasma. Though it has yet to be definitively tested, convective theory is often invoked to explain experimental observations, even when one or more of the theory's assumptions are violated. In contrast, the experiments reported here not only obeyed the assumptions of the theory, but were also conducted in plasmas with peak densities well below quarter-critical density. This prevented other competing or coexisting phenomena from occurring, thereby providing clearly interpretable results. These are the first SBS experiments that were designed to be both a clear test of linear convective theory and pertinent to controlled fusion research. A crucial part of this series of experiments was the development of a new instrument, the Multiple Angle Time Resolving Spectrometer (MATRS). MATRS has the unique capability of both spectrally and temporally resolving absolute levels of scattered light at many angles simultaneously, and is the first of its kind used in laser-plasma experiments. A detailed comparison of the theoretical predictions and the experimental observations is made

  4. Wire Array Z-pinches on Sphinx Machine: Experimental Results and Relevant Points of Microsecond Implosion Physics

    International Nuclear Information System (INIS)

    Calamy, H.; Hamann, F.; Lassalle, F.; Bayol, F.; Mangeant, C.; Morell, A.; Huet, D.; Bedoch, J.P.; Chittenden, J.P.; Lebedev, S.V.; Jennings, C.A.; Bland, S.N.

    2006-01-01

    Centre d'Etudes de Gramat (France) has developed an efficient long implosion time (800 ns) Aluminum plasma radiation source (PRS). Based on the LTD technology, the SPHINX facility is developed as a 1-3MJ, 1μs rise time, 4-10 MA current driver. In this paper, it was used in 1MJ, 4MA configuration to drive Aluminum nested wire arrays Z-pinches with K-shell yield up to 20 kJ and a FWHM of the x-ray pulse of about 50 ns. We present latest SPHINX experiments and some of the main physic issues of the microsecond regime. Experimental setup and results are described with the aim of giving trends that have been obtained. The main features of microsecond implosion of wire arrays can be analyzed thanks to same methods and theories as used for faster Z-pinches. The effect of load polarity was examined. The stability of the implosion , one of the critical point of microsecond wire arrays due to the load dimensions imposed by the time scale, is tackled. A simple scaling from 100 ns Z-pinch results to 800 ns ones gives good results and the use of nested arrays improves dramatically the implosion quality and the Kshell yield of the load. However, additional effects such as the impact of the return current can geometry on the implosion have to be taken into account on our loads. Axial inhomogeneity of the implosion the origin of which is not yet well understood occurs in some shots and impacts the radiation output. The shape of the radiative pulse is discussed and compared with the homogeneity of the implosion. Numerical 2D R-Z and R-θ simulations are used to highlight some experimental results and understand the plasma conditions during these microsecond wire arrays implosions

  5. Experimental Measures of Bus Comfort Levels Using Kinematic Parameters Recorded by Smartphone

    Energy Technology Data Exchange (ETDEWEB)

    Aquila, S. dell' ; Eboli, L.; Futia, G.; Mazzulla, G.; Pungillo, G.

    2016-07-01

    Comfort on board plays an essential role in the levels of satisfaction of a bus service perceived by passengers. The aim of this paper is to propose a measure of comfort based on two kinds of data: perceptions of passengers (subjective data) and accelerations of bus (objective data). For the collection of subjective data a questionnaire was addressed to a sample of university students, while a smartphone, equipped with GPS device and 3-axis accelerometer, was used to record the accelerations. Based on the recorded parameters, we determined the thresholds of the acceleration values beyond which the level of comfort cannot be considered as good.. (Author)

  6. Tire-road noise: an experimental study of tire and road design parameters

    OpenAIRE

    Bekke, Dirk; Wijnant, Ysbrand H.; Weegerink, Thijs; de Boer, Andries

    2013-01-01

    It is widely known that road traffic noise has negative influences on human health. Hence, as tire-road noise is considered to be the most dominant cause of road traffic noise above 30-50 km/h, a lot of research is performed by the two involving industries: road authorities/manufacturers and tire manufacturers. Usually, the parameters influencing exterior tire-road noise are often examined separately, whereas it is the tire-road interaction which obviously causes the actual noise. An integral...

  7. Using numerical simulations to extract parameters of toroidal electron plasmas from experimental data

    DEFF Research Database (Denmark)

    Ha, B. N.; Stoneking,, M. R.; Marler, Joan

    2009-01-01

    Measurements of the image charge induced on electrodes provide the primary means of diagnosing plasmas in the Lawrence Non-neutral Torus II (LNT II) [Phys. Rev. Lett. 100, 155001 (2008)]. Therefore, it is necessary to develop techniques that determine characteristics of the electron plasma from......, as in the cylindrical case. In the toroidal case, additional information about the m=1 motion of the plasma can be obtained by analysis of the image charge signal amplitude and shape. Finally, results from the numerical simulations are compared to experimental data from the LNT II and plasma characteristics...

  8. The piezo-magnetic parameters of Terfenol-D: An experimental viewpoint

    International Nuclear Information System (INIS)

    Davino, D.; Giustiniani, A.; Visone, C.

    2012-01-01

    Magnetostrictive and all multifunctional materials have experienced in the last decades a growing technological interest. Several contributions, in the literature, propose the above-mentioned materials in innovative sensors and actuators both for bulk and MEMS devices. More recently, magnetostrictive materials have been proposed for energy harvesting applications by exploiting the so-called Villari effect. In this case, the behavior and the amplitude of the piezo-magnetic coefficients are an important element to evaluate the conversion efficiency. Aim of this paper is to study the experimental behavior of the piezo-magnetic coefficients of a commercial Terfenol-D rod under controlled conditions.

  9. Experimental Analyses of the Major Parameters Affecting the Intensity of Outbursts of Coal and Gas

    Science.gov (United States)

    Nie, W.; Peng, S. J.; Xu, J.; Liu, L. R.; Wang, G.; Geng, J. B.

    2014-01-01

    With an increase in mining depth and production, the intensity and frequency of outburst of coal and gas have a tendency to increase. Estimating the intensity of outbursts of coal and gas plays an important role because of its relation with the risk value. In this paper, we described the semiquantitative relations between major parameters and intensity of outburst based on physical experiments. The results showed increment of geostress simulated by horizontal load (from 1.4, 2.4, 3.2, to 3.4 MPa) or vertical load (from 2, 3, 3.6, to 4 MPa) improved the relative intensity rate (3.763–7.403% and 1.273–7.99%); the increment of porosity (from 1.57, 2.51, 3, to 3.6%) improved the relative intensity rate from 3.8 to 13.8%; the increment of gas pressure (from 0, 0.5, 0.65, 0.72, 1, to 1.5 Mpa) induced the relative intensity rate to decrease from 38.22 to 0%; the increment of water content (from 0, 2, 4, to 8%) caused the relative intensity rate to drop from 5.425 to 0.5%. Furthermore, sensitivity and range analysis evaluates coupled factors affecting the relative intensity. In addition, the distinction with initiation of outburst of coal and gas affected by these parameters is discussed by the relative threshold of gas content rate. PMID:25162042

  10. Experimental verification of internal parameter in magnetically coupled boost used as PV optimizer in parallel association

    Science.gov (United States)

    Sawicki, Jean-Paul; Saint-Eve, Frédéric; Petit, Pierre; Aillerie, Michel

    2017-02-01

    This paper presents results of experiments aimed to verify a formula able to compute duty cycle in the case of pulse width modulation control for a DC-DC converter designed and realized in laboratory. This converter, called Magnetically Coupled Boost (MCB) is sized to step up only one photovoltaic module voltage to supply directly grid inverters. Duty cycle formula will be checked in a first time by identifying internal parameter, auto-transformer ratio, and in a second time by checking stability of operating point on the side of photovoltaic module. Thinking on nature of generator source and load connected to converter leads to imagine additional experiments to decide if auto-transformer ratio parameter could be used with fixed value or on the contrary with adaptive value. Effects of load variations on converter behavior or impact of possible shading on photovoltaic module are also mentioned, with aim to design robust control laws, in the case of parallel association, designed to compensate unwanted effects due to output voltage coupling.

  11. Experimental Investigation and Optimization of TIG Welding Parameters on Aluminum 6061 Alloy Using Firefly Algorithm

    Science.gov (United States)

    Kumar, Rishi; Mevada, N. Ramesh; Rathore, Santosh; Agarwal, Nitin; Rajput, Vinod; Sinh Barad, AjayPal

    2017-08-01

    To improve Welding quality of aluminum (Al) plate, the TIG Welding system has been prepared, by which Welding current, Shielding gas flow rate and Current polarity can be controlled during Welding process. In the present work, an attempt has been made to study the effect of Welding current, current polarity, and shielding gas flow rate on the tensile strength of the weld joint. Based on the number of parameters and their levels, the Response Surface Methodology technique has been selected as the Design of Experiment. For understanding the influence of input parameters on Ultimate tensile strength of weldment, ANOVA analysis has been carried out. Also to describe and optimize TIG Welding using a new metaheuristic Nature - inspired algorithm which is called as Firefly algorithm which was developed by Dr. Xin-She Yang at Cambridge University in 2007. A general formulation of firefly algorithm is presented together with an analytical, mathematical modeling to optimize the TIG Welding process by a single equivalent objective function.

  12. Why we should use simpler models if the data allow this: relevance for ANOVA designs in experimental biology

    Directory of Open Access Journals (Sweden)

    Lazic Stanley E

    2008-07-01

    Full Text Available Abstract Background Analysis of variance (ANOVA is a common statistical technique in physiological research, and often one or more of the independent/predictor variables such as dose, time, or age, can be treated as a continuous, rather than a categorical variable during analysis – even if subjects were randomly assigned to treatment groups. While this is not common, there are a number of advantages of such an approach, including greater statistical power due to increased precision, a simpler and more informative interpretation of the results, greater parsimony, and transformation of the predictor variable is possible. Results An example is given from an experiment where rats were randomly assigned to receive either 0, 60, 180, or 240 mg/L of fluoxetine in their drinking water, with performance on the forced swim test as the outcome measure. Dose was treated as either a categorical or continuous variable during analysis, with the latter analysis leading to a more powerful test (p = 0.021 vs. p = 0.159. This will be true in general, and the reasons for this are discussed. Conclusion There are many advantages to treating variables as continuous numeric variables if the data allow this, and this should be employed more often in experimental biology. Failure to use the optimal analysis runs the risk of missing significant effects or relationships.

  13. MRI in the early stage of spinal cord injury: does it have clinical relevance? An experimental study

    International Nuclear Information System (INIS)

    Hannmann, T.T.; Freund, M.

    2007-01-01

    Purpose: An experimental technique for producing a ventral spinal trauma which imitates a slipped intervertebral disc or a fractured vertebra was evaluated using magnetic resonance imaging and histology. The results were evaluated with respect to their clinical importance. Materials and Methods: A total of 69 Wistar rats were used for this study. An inflatable angioplasty balloon device was placed dorsally or ventrally to the spinal cord in order to produce a spinal trauma. 30 rats were used to compare neurological pathologies between ventral and dorsal trauma. 30 animals underwent graded ventral spinal cord compression. Magnetic resonance imaging was performed and the results were compared to histology. Results: Using this technique, the balloon device can be placed ventrally to the spinal cord. The compression time had a direct effect on changes on magnetic resonance images and edema in histology, but a longer compression time did not produce increased bleeding. The T2-weighted MRI scans showed hyperintense changes immediately after spinal compression. Therefore, they are the appropriate way for diagnosing acute spinal injuries. Although the T1-weighted MRI scans did not change after spinal compression, they are important for diagnosing epidural hematomas. (orig.)

  14. Radiosensitization by SAHA in Experimental Colorectal Carcinoma Models-In Vivo Effects and Relevance of Histone Acetylation Status

    International Nuclear Information System (INIS)

    Folkvord, Sigurd; Ree, Anne Hansen; Furre, Torbjorn; Halvorsen, Thomas; Flatmark, Kjersti

    2009-01-01

    Purpose: Histone deacetylase inhibitors are being evaluated as antitumor agents in ongoing clinical trials, and promising preclinical results, combined with favorable toxicity profiles, have rendered the drugs as interesting candidates for combination with other treatment modalities, such as radiotherapy. The aim of the present study was to evaluate the radiosensitizing properties of suberoylanilide hydroxamic acid (SAHA) and the possible requirement of histone hyperacetylation at radiation exposure. Methods and materials: Radiosensitization by SAHA was assessed in a colorectal carcinoma cell line and in two colorectal xenograft models by analysis of clonogenic survival and tumor growth delay, respectively. Histone acetylation status at radiation exposure was evaluated by Western blot. Results: In vitro, radiosensitization was demonstrated when cells were preincubated with SAHA, and, in the xenografts, tumor growth was delayed when the mice were treated with fractionated radiation combined with daily SAHA injections compared with radiation alone. Surprisingly, the SAHA-dependent growth delay was still present when radiation was delivered at restored baseline acetylation levels compared with maximal histone hyperacetylation. Conclusion: SAHA was an effective radiosensitizer in experimental colorectal carcinoma models, suggesting that histone deacetylase inhibition might constitute a valuable supplement to current multimodal treatment strategies in rectal cancer. The presence of histone hyperacetylation at radiation was not required to obtain an increased radiation response, questioning the validity of using histone hyperacetylation as a molecular marker for radiosensitivity.

  15. Colloid facilitated transport in fractured rocks: parameter estimation and comparison with experimental data

    International Nuclear Information System (INIS)

    Viswanthan, H.S.; Wolfsberg, A.V.; Reimus, P.W.; Ware, D.; Lu, G.

    2003-01-01

    Colloid-facilitated migration of plutonium in fractured rock has been implicated in both field and laboratory studies. Other reactive radionuclides may also experience enhanced mobility due to groundwater colloids. Model prediction of this process is necessary for assessment of contaminant boundaries in systems for which radionuclides are already in the groundwater and for performance assessment of potential repositories for radioactive waste. Therefore, a reactive transport model is developed and parameterized using results from controlled laboratory fracture column experiments. Silica, montmorillonite and clinoptilolite colloids are used in the experiments along with plutonium and Tritium. The goal of the numerical model is to identify and parameterize the physical and chemical processes that affect the colloid-facilitated transport of plutonium in the fractures. The parameters used in this model are similar in form to those that might be used in a field-scale transport model

  16. Influence of experimental parameters inherent to optical fibers on Quantum Key Distribution, the protocol BB84

    Directory of Open Access Journals (Sweden)

    L. Bouchoucha

    2018-03-01

    Full Text Available In this work, we represent the principle of quantum cryptography (QC that is based on fundamental laws of quantum physics. QC or Quantum Key Distribution (QKD uses various protocols to exchange a secret key between two communicating parties. This research paper focuses and examines the quantum key distribution by using the protocol BB84 in the case of encoding on the single-photon polarization and shows the influence of optical components parameters on the quantum key distribution. We also introduce Quantum Bit Error Rate (QBER to better interpret our results and show its relationship with the intrusion of the eavesdropper called Eve on the optical channel to exploit these vulnerabilities.

  17. THE EXPERIMENTAL DIDACTIC STAND FOR DETERMINING THE PARAMETERS OF THE GEAR WITH MAGNETORHEOLOGICAL CLUTCH AND BRAKE

    Directory of Open Access Journals (Sweden)

    Jerzy BAJKOWSKI

    2014-03-01

    Full Text Available In this paper the laboratory stand, designed to be used as a part of the Laboratory of Machine Design and Research which is part of the subject Fundamentals of Machine Design, is presented. Originally the laboratory stand was designed as an element of one of the research projects, and the adopted for didactic purposes. The students have the chance to get familiar with unique type of fluids controlled by the magnetic field and their application in the special purpose devices. The laboratory stand allows to conduct individual measurements of the torque, for different coil currents which generate the magnetic field. In the final report students provide the results with the individual analysis of the system parameters.

  18. Experimental determination of fuel element parameters; Eksperimentalno odredjivanje parametara gorivnog elementa

    Energy Technology Data Exchange (ETDEWEB)

    Takac, S; Zdravkoovic, Z; Ivkovic, N; Sotic, O; Krcevinac, S [Boris Kidric Institute of Nuclear Sciences Vinca, Beograd (Yugoslavia)

    1968-04-15

    The objective of the experiments described was to study the applicability of heterogeneous reactor theory. The properties of the following fuel elements were measured: natural uranium rod, 2% enriched uranium tube; natural uranium oxide fuel cluster. Thermal neutron flux density in and around a single fuel element, {gamma} thermal constant factor, and {eta} multiplication constant were analyzed for fuel cluster dependent on the lattice pitch of fuel pins in the cluster. Measurement {gamma} and {eta} values were compared to calculation results obtained by TER-3 code (Amoyal-Benoist method). Special attention was devoted to improvement of experimental technique and study of micro perturbation in simple and complex elementary cells with the aim to obtain exact thermal neutron flux distribution in reactor cell.

  19. Experimental investigations on steel-concrete composite columns for varying parameters

    Science.gov (United States)

    Aparna, V.; Vivek, D.; Neelima, Kancharla; Karthikeyan, B.

    2017-07-01

    In this study, the experimental investigations on steel tubes filled with different types of concrete are presented. Steel tubes filled with fibre reinforced concrete using lathe waste and steel tube with concerned confined with steel mesh were investigated. The combinations were compared with steel tubes with conventional concrete. A total of 4 concrete filled steel tube (CFST) combinations were made with tubes of diameter 100 mm with wall thickness 1.6 mm and a height of 300 mm. Axial compression test to examine the resisting capacity of the columns and push-out test for noting the bond strength were performed. Coupon tests were also conducted to determine the mechanical properties of steel. The structural behaviour of the composite columns was evaluated from on the test results. It was observed that steel tube filled fibre reinforced possessed better bond strength and resistance to axial load.

  20. Experimental basis for parameters contributing to energy dissipation in piping systems

    International Nuclear Information System (INIS)

    Ibanez, P.; Ware, A.G.

    1985-01-01

    The paper reviews several pipe testing programs to suggest the phenomena causing energy dissipation in piping systems. Such phenomena include material damping, plasticity, collision in gaps and between pipes, water dynamics, insulation straining, coupling slippage, restraints (snubbers, struts, etc.), and pipe/structure interaction. These observations are supported by a large experimental data base. Data are available from in-situ and laboratory tests (pipe diameters up to about 20 inches, response levels from milli-g's to responses causing yielding, and from excitation wave forms including sinusoid, snapback, random, and seismic). A variety of pipe configurations have been tested, including simple, bare, straight sections and complex lines with bends, snubbers, struts, and insulation. Tests have been performed with and without water and at zero to operating pressure. Both light water reactor and LMFBR piping have been tested

  1. Experimental investigation into effect of cutting parameters on surface integrity of hardened tool steel

    Science.gov (United States)

    Bashir, K.; Alkali, A. U.; Elmunafi, M. H. S.; Yusof, N. M.

    2018-04-01

    Recent trend in turning hardened materials have gained popularity because of its immense machinability benefits. However, several machining processes like thermal assisted machining and cryogenic machining have reveal superior machinability benefits over conventional dry turning of hardened materials. Various engineering materials have been studied. However, investigations on AISI O1 tool steel have not been widely reported. In this paper, surface finish and surface integrity dominant when hard turning AISI O1 tool steel is analysed. The study is focused on the performance of wiper coated ceramic tool with respect to surface roughness and surface integrity of hardened tool steel. Hard turned tool steel was machined at varying cutting speed of 100, 155 and 210 m/min and feed rate of 0.05, 0.125 and 0.20mm/rev. The depth of cut of 0.2mm was maintained constant throughout the machining trials. Machining was conducted using dry turning on 200E-axis CNC lathe. The experimental study revealed that the surface finish is relatively superior at higher cutting speed of 210m/min. The surface finish increases when cutting speed increases whereas surface finish is generally better at lower feed rate of 0.05mm/rev. The experimental study conducted have revealed that phenomena such as work piece vibration due to poor or improper mounting on the spindle also contributed to higher surface roughness value of 0.66Ra during turning at 0.2mm/rev. Traces of white layer was observed when viewed with optical microscope which shows evidence of cutting effects on the turned work material at feed rate of 0.2 rev/min

  2. Study of experimentally undetermined neutrino parameters in the light of baryogenesis considering type I and type II Seesaw models

    International Nuclear Information System (INIS)

    Kalita, Rupam

    2017-01-01

    We study to connect all the experimentally undetermined neutrino parameters namely lightest neutrino mass, neutrino CP phases and baryon asymmetry of the Universe within the framework of a model where both type I and type II seesaw mechanisms can contribute to tiny neutrino masses. In this work we study the effects of Dirac and Majorana neutrino phases in the origin of matter-antimatter asymmetry through the mechanism of leptogenesis. Type I seesaw mass matrix considered to a tri-bimaximal (TBM) type neutrino mixing which always gives non zero reactor mixing angle. The type II seesaw mass matrix is then considered in such a way that the necessary deviation from TBM mixing and the best fit values of neutrino parameters can be obtained when both type I and type II seesaw contributions are taken into account. We consider different contribution from type I and type II seesaw mechanism to study the effects of neutrino CP phases in the baryon asymmetry of the universe. We further study to connect all these experimentally undetermined neutrino parameters by considering various contribution of type I and type II seesaw. (author)

  3. Refined Dummy Atom Model of Mg(2+) by Simple Parameter Screening Strategy with Revised Experimental Solvation Free Energy.

    Science.gov (United States)

    Jiang, Yang; Zhang, Haiyang; Feng, Wei; Tan, Tianwei

    2015-12-28

    Metal ions play an important role in the catalysis of metalloenzymes. To investigate metalloenzymes via molecular modeling, a set of accurate force field parameters for metal ions is highly imperative. To extend its application range and improve the performance, the dummy atom model of metal ions was refined through a simple parameter screening strategy using the Mg(2+) ion as an example. Using the AMBER ff03 force field with the TIP3P model, the refined model accurately reproduced the experimental geometric and thermodynamic properties of Mg(2+). Compared with point charge models and previous dummy atom models, the refined dummy atom model yields an enhanced performance for producing reliable ATP/GTP-Mg(2+)-protein conformations in three metalloenzyme systems with single or double metal centers. Similar to other unbounded models, the refined model failed to reproduce the Mg-Mg distance and favored a monodentate binding of carboxylate groups, and these drawbacks needed to be considered with care. The outperformance of the refined model is mainly attributed to the use of a revised (more accurate) experimental solvation free energy and a suitable free energy correction protocol. This work provides a parameter screening strategy that can be readily applied to refine the dummy atom models for metal ions.

  4. Evaluation of the effect of conventionally prepared swarna makshika bhasma on different bio-chemical parameters in experimental animals

    Directory of Open Access Journals (Sweden)

    Sudhaldev Mohapatra

    2011-01-01

    Full Text Available Swarna makshika (chalcopyrite bhasma (SMB has been used for different therapeutic purposes since long in Ayurveda. The present study is conducted to evaluate the effect of conventionally prepared SMB on different bio-chemical parameters in experimental animals, for providing scientific data base for its logical use in clinical practice. The genuine SMB was prepared by following classical techniques of shodhana and marana most commonly used by different Ayurvedic drug manufacturers. Shodhana was done by roasting raw swarna makshika with lemon juice for three days and marana was performed by 11 putas . The experimental animals (rats were divided into two groups. SMB mixed with diluted honey was administered orally in therapeutic dose to Group SMB and diluted honey only was administered to vehicle control Group, for 30 days. The blood samples were collected twice, after 15 days and after 30 days of drug administration and different biochemical investigations were done. Biochemical parameters were chosen based on references from Ayurvedic classics and contemporary medicine. It was observed that Hb% was found significantly increased and LDL and VLDL were found significantly decreased in Group SMB when compared with vehicle control group. This experimental data will help the clinician for the logical use of SMB in different disease conditions with findings like low Hb% and high LDL, VLDL levels.

  5. Transfer of elements relevant to nuclear fuel cycle from soil to boreal plants and animals in experimental meso- and microcosms

    Energy Technology Data Exchange (ETDEWEB)

    Tuovinen, Tiina S., E-mail: tiina.tuovinen@uef.fi [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Kasurinen, Anne; Häikiö, Elina [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Tervahauta, Arja [Department of Biology, University of Eastern Finland, P.O. Box FI-70211, Kuopio (Finland); Makkonen, Sari; Holopainen, Toini; Juutilainen, Jukka [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland)

    2016-01-01

    Uranium (U), cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), thorium (Th) and zinc (Zn) occur naturally in soil but their radioactive isotopes can also be released into the environment during the nuclear fuel cycle. The transfer of these elements was studied in three different trophic levels in experimental mesocosms containing downy birch (Betula pubescens), narrow buckler fern (Dryopteris carthusiana) and Scandinavian small-reed (Calamagrostis purpurea ssp. Phragmitoides) as producers, snails (Arianta arbostorum) as herbivores, and earthworms (Lumbricus terrestris) as decomposers. To determine more precisely whether the element uptake of snails is mainly via their food (birch leaves) or both via soil and food, a separate microcosm experiment was also performed. The element uptake of snails did not generally depend on the presence of soil, indicating that the main uptake route was food, except for U, where soil contact was important for uptake when soil U concentration was high. Transfer of elements from soil to plants was not linear, i.e. it was not correctly described by constant concentration ratios (CR) commonly applied in radioecological modeling. Similar nonlinear transfer was found for the invertebrate animals included in this study: elements other than U were taken up more efficiently when element concentration in soil or food was low. - Highlights: • We studied transfer of elements in boreal food chain using meso- and microcosms. • Elements related to nuclear fuel cycle and mining were examined. • Higher uptake at lower soil concentrations was observed for primary producers. • Snails took up elements mainly from food but for U also soil was an element source. • Non-linear transfer of essential elements was observed for herbivore and decomposer.

  6. Can analysis of Platichthys flesus otoliths provide relevant data on historical metal pollution in estuaries? Experimental and in situ approaches

    International Nuclear Information System (INIS)

    Selleslagh, Jonathan; Echard, Aurélie; Pécheyran, Christophe; Baudrimont, Magalie; Lobry, Jérémy; Daverat, Françoise

    2016-01-01

    otoliths were complex, the concentrations were correlated with those in the water. Analysis of flounder specimens collected from 2007 to 2014 in the Gironde estuary (SW France) showed interannual variability in Pb concentrations, with higher values for fish otoliths from 2007 to 2010 than those from 2012 to 2014. This trend indicated a decrease in Pb in the Gironde estuary over the last decade, which is consistent with the results of other surveys on bivalves. Our study demonstrates that it is possible to use otolith microchemistry as a tool in assessing and retracing long-term metal pollution in estuarine systems. - Highlights: • Platichthys flesus was exposed to a cocktail of metals at realistic environmental concentrations. • Bioaccumulation of metals in tissue and otolith was linked to exposure level. • Cartography of metal in fish otolith was realized for the first time. • Otolith microchemistry of P. flesus was suggested as relevant tool to assess and retrace metal pollution. • Otoliths of P. flesus specimens collected from 2007 to 2014 in the Gironde estuary were analyzed

  7. Can analysis of Platichthys flesus otoliths provide relevant data on historical metal pollution in estuaries? Experimental and in situ approaches

    Energy Technology Data Exchange (ETDEWEB)

    Selleslagh, Jonathan, E-mail: Jonathan.Selleslagh@u-bordeaux.fr [Université de Bordeaux, CNRS, UMR EPOC 5805, Station Marine d' Arcachon, place du docteur Peyneau, 33120 Arcachon (France); Echard, Aurélie [IRSTEA Centre de Bordeaux, unité EABX, 50 avenue de Verdun, 33612 Cestas (France); Pécheyran, Christophe [Université de Pau et des pays de l' Adour, CNRS, LCABIE-IPREM UMR 5254, 64053 Pau (France); Baudrimont, Magalie [Université de Bordeaux, CNRS, UMR EPOC 5805, Station Marine d' Arcachon, place du docteur Peyneau, 33120 Arcachon (France); Lobry, Jérémy; Daverat, Françoise [IRSTEA Centre de Bordeaux, unité EABX, 50 avenue de Verdun, 33612 Cestas (France)

    2016-07-01

    otoliths were complex, the concentrations were correlated with those in the water. Analysis of flounder specimens collected from 2007 to 2014 in the Gironde estuary (SW France) showed interannual variability in Pb concentrations, with higher values for fish otoliths from 2007 to 2010 than those from 2012 to 2014. This trend indicated a decrease in Pb in the Gironde estuary over the last decade, which is consistent with the results of other surveys on bivalves. Our study demonstrates that it is possible to use otolith microchemistry as a tool in assessing and retracing long-term metal pollution in estuarine systems. - Highlights: • Platichthys flesus was exposed to a cocktail of metals at realistic environmental concentrations. • Bioaccumulation of metals in tissue and otolith was linked to exposure level. • Cartography of metal in fish otolith was realized for the first time. • Otolith microchemistry of P. flesus was suggested as relevant tool to assess and retrace metal pollution. • Otoliths of P. flesus specimens collected from 2007 to 2014 in the Gironde estuary were analyzed.

  8. Simulation and Experimental Determination of Technological Liquid Molding Parameters of Tubing Basalt Insulation

    Directory of Open Access Journals (Sweden)

    Yu. V. Badanina

    2015-01-01

    Full Text Available The article is dedicated to one of the most important and urgent tasks in mechanical engineering development - the creation of low-density and environmentally-friendly thermoinsulation from available cheap basalt fibers for products to operate at temperatures up to 700°C.One of the most effective applications of such thermo-insulation is to develop and provide highly porous coatings from short basalt fibers by liquid filtration for tubing (T to supply superheated up to 420° C steam under pressure of 35 MPa in the deep layers with severe highviscosity oil. Tubing with the short low-density basalt insulation can be used for a greater depth than the vacuum-insulated tubing, which are also called "thermo-cases", and do not fully meet business needs for long-term reliability of oil vacuum tubes, too large mass per unit length of their design and, as a consequence, the impossibility to use such pipes for deep wells.The aim of the work is to simulate a liquid filtration process of short fibers and determine technological parameters of producing thermal insulation coatings of tubing pipes from basalt fibers and mineral binder shaped as cylinders and cylindrical shells. The paper proposes a mathematical model of free filtration deposition of short fibers from liquid slurry, which describes dynamics of creating thermal insulation products and allows us to determine the rational parameters of their manufacturing process. It shows methods to improve the products quality while forming the thermal insulation by filtration through additional vacuum deposition of a filtrate chamber and the final prepressing of sediment layer, giving dimensions and shape to the final product.The paper defines a prescription hydro mass composition. It shows that to increase the compressive strength of highly fibrous rings and cylindrical shells it is necessary to use based on oxide А12O3 5-7% by weight mineral binder, which fixes basalt fibers in places of their contacts. It

  9. Experimental studies of relevance on zirconium nitrate raffinate sludge for its disposal as well as zirconium recovery

    International Nuclear Information System (INIS)

    Brahmananda Reddy, G.; Narasimha Murty, B.; Ravindra, H.R.

    2013-01-01

    One of the many routes of production of nuclear grade zirconium dioxide involve separation of zirconium and hafnium by solvent extraction of zirconium nitrate using tri-n-butyl phosphate followed by precipitation of zirconium with ammonia and finally calcination of the so obtained hydrated zirconia at elevated temperature. The zirconium feed solution as is generated from digestion of zirconium washed dried frit (produced by the caustic fusion of zircon sand which is one of the beach sand heavy minerals) in nitric acid contain considerable amount of sludge material and after solvent extraction this whole sludge material rests with raffinate. This sludge material has a scope to contain considerable amounts of zirconium along with other metal ions such as hafnium, aluminium, iron, etc. besides nitric acid and it constitutes one of the important solid wastes that needs to be disposed suitably. One of the disposal means of this sludge material is to use it as a land fill for which two important criteria are to be viz the pH of 10% solid waste solution should be near to neutral pH and the loss on ignition at 550℃ on dry basis of the sludge to be below 20%. In order to study the implications of presence of varying amounts of zirconium nitrate in the sludge on the pH of 10% solution of the sludge various synthetic zirconium nitrate solid waste were prepared using the sludge material generated at the laboratory during the analysis of zirconium washed dried frit. Presence of zirconium in the sludge is expected to decrease the overall pH of the 10% solution of the sludge because zirconium is prone to hydrolyze especially locally when zirconium ion comes into contact with water according to the chemical equation Zr 4+ H 2 O → ZrO 2+ + 2H + . From this equation, it is clear that for every one mole of zirconium ions two moles of hydrogen ions are produced. This is verified experimentally using the synthetically prepared sludge materials with varying amounts of zirconium

  10. Experimental researches of marine wave parameters in the Black Sea Basin

    Science.gov (United States)

    Panaitescu, Fanel-Viorel; Panaitescu, Mariana; Anton, Iulia-Alina

    2016-12-01

    In this paper are presented the process of measuring parameters of marine waves with performed devices which permit to obtain the values of the speed and current division marine wave amplitude and direction of the wave at each measurement, the number of measurements, date, hour, minute and second of measurement. This monitoring, which comprises the period of one year including, reveals an amplitude an annual average of the wave of hmed=1.53 m, obtained by taking maximum envelope appeared in a measurement range of 120 seconds. The value is unexpectedly high, taking into account of the fact that on the coastline it was found of: hmed =0.467 m at Constanta Station and hmed =0.23 m at Mangalia Station. These results reveal that there is a energy potential that exceeds expectations, much larger in the area of off shore, that is to say, in more than 12 Mm off shore, in front of the coastal zone. These measurements were applied with two devices-one device for measuring hidrostatic amplitude test and other device, ADV(Advanced Doppler velocymmeter).

  11. Experimental study on effects of drilling parameters on respirable dust production during roof bolting operations.

    Science.gov (United States)

    Jiang, Hua; Luo, Yi; McQuerrey, Joe

    2018-02-01

    Underground coalmine roof bolting operators exhibit a continued risk for overexposure to airborne levels of respirable coal and crystalline silica dust from the roof drilling operation. Inhaling these dusts can cause coal worker's pneumoconiosis and silicosis. This research explores the effect of drilling control parameters, specifically drilling bite depth, on the reduction of respirable dust generated during the drilling process. Laboratory drilling experiments were conducted and results demonstrated the feasibility of this dust control approach. Both the weight and size distribution of the dust particles collected from drilling tests with different bite depths were analyzed. The results showed that the amount of total inhalable and respirable dust was inversely proportional to the drilling bite depth. Therefore, control of the drilling process to achieve proper high-bite depth for the rock can be an important approach to reducing the generation of harmful dust. Different from conventional passive engineering controls, such as mist drilling and ventilation approaches, this approach is proactive and can cut down the generation of respirable dust from the source. These findings can be used to develop an integrated drilling control algorithm to achieve the best drilling efficiency as well as reducing respirable dust and noise.

  12. Experimentally verified inductance extraction and parameter study for superconductive integrated circuit wires crossing ground plane holes

    International Nuclear Information System (INIS)

    Fourie, Coenrad J; Wetzstein, Olaf; Kunert, Juergen; Meyer, Hans-Georg; Toepfer, Hannes

    2013-01-01

    As the complexity of rapid single flux quantum (RSFQ) circuits increases, both current and power consumption of the circuits become important design criteria. Various new concepts such as inductive biasing for energy efficient RSFQ circuits and inductively coupled RSFQ cells for current recycling have been proposed to overcome increasingly severe design problems. Both of these techniques use ground plane holes to increase the inductance or coupling factor of superconducting integrated circuit wires. New design tools are consequently required to handle the new topographies. One important issue in such circuit design is the accurate calculation of networks of inductances even in the presence of finite holes in the ground plane. We show how a fast network extraction method using InductEx, which is a pre- and post-processor for the magnetoquasistatic field solver FastHenry, is used to calculate the inductances of a set of SQUIDs (superconducting quantum interference devices) with ground plane holes of different sizes. The results are compared to measurements of physical structures fabricated with the IPHT Jena 1 kA cm −2 RSFQ niobium process to verify accuracy. We then do a parameter study and derive empirical equations for fast and useful estimation of the inductance of wires surrounded by ground plane holes. We also investigate practical circuits and show excellent accuracy. (paper)

  13. Experimental study on plasma parameters in the mushroom limiter shadow in the T-10 tokamak

    International Nuclear Information System (INIS)

    Alferov, A.A.; Vershkov, V.A.; Grashin, S.A.; Chankin, A.V.

    1988-01-01

    Plasma parameters in the shadow of mashroom limiter installed in the lower tokamak outlet are studied. Investigation into asymmetry of plasma fluxes to the ion and electrone limiter sides leads to a consumption concerning two meachanisms of its occurrance-toroidal plasma rotation and prevailing plasma departure to the wall through the external torus encirclement. Asymmetry of plasma drift potentials near the limiter observed during the experiment leads to current drift through the limiter close to Spitzer j s one. It is shown that with the increase of mean plasma density the plasma density in the limiter channels grows and its temperature is decreased so the charged particle losses for the limiter are weakly dependent on the mean density which is connected with plasma confinement degradation under the density reduction. A complete flux of charged particles to the limiter is comparable to their flux from plasma filament. Plasma flux into the channels is close to ambipolar one and the power fluxes to neutralization plates are of the order of 10 j s Te/e. Neutral gas pressure dependence in the volume under the limiter on the plasma fluxes to channels is nonlinear, the maximum pressure achieves 3x10 -2 T

  14. Correlation between muscle electrical impedance data and standard neurophysiologic parameters after experimental neurogenic injury

    International Nuclear Information System (INIS)

    Ahad, M; Rutkove, S B

    2010-01-01

    Previous work has shown that electrical impedance measurements of muscle can assist in quantifying the degree of muscle atrophy resulting from neuronal injury, with impedance values correlating strongly with standard clinical parameters. However, the relationship between such data and neurophysiologic measurements is unexplored. In this study, 24 Wistar rats underwent sciatic crush, with measurement of the 2–1000 kHz impedance spectrum, standard electrophysiological measures, including nerve conduction studies, needle electromyography, and motor unit number estimation (MUNE) before and after sciatic crush, with animals assessed weekly for 4 weeks post-injury. All electrical impedance values, including a group of 'collapsed' variables, in which the spectral characteristics were reduced to single values, showed reductions as high as 47.2% after sciatic crush, paralleling and correlating with changes in compound motor action potential amplitude, conduction velocity and most closely to MUNE, but not to the presence of fibrillation potentials observed on needle electromyography. These results support the concept that localized impedance measurements can serve as surrogate makers of nerve injury; these measurements may be especially useful in assessing nerve injury impacting proximal or axial muscles where standard quantitative neurophysiologic methods such as nerve conduction or MUNE cannot be readily performed

  15. Preventive effects of hydroalcoholic extract of saffron on hematological parameters of experimental asthmatic rats

    Directory of Open Access Journals (Sweden)

    Somayyeh Vosooghi

    2013-05-01

    Full Text Available Objective: Asthma is a chronic inflammatory disease of the respiratory airways distinguished by edema and infiltration of inflammatory immune cells. To test our hypothesis about the anti-inflammatory effect of saffron, we examined effects of Crocus sativus (C. sativus extract as a prophylactic anti-inflammatory agent in sensitized rats. Materials and Methods: To induce experimental asthma, rats were sensitized with injection and inhalation of ovalbumin (OA. Forty male Wistar rats were divided into 5 groups (n=8 for each: control, sensitized (asthma, and sensitized and pretreated with three different concentrations of extract, 50, 100, and 200 mg/kg, 2 times a week (group asthma+50EX, group asthma+100EX, and group asthma+200EX. After 32 days, total white blood cells (WBC counts, red blood cells (RBC, and platelet counts in blood were examined. Results: Total WBC number and eosinophil and neutrophil percentage in blood were increased, but lymphocyte decreased in sensitized animals compared with those of control group (pConclusion: Our findings indicated that the extract of C. sativus could be useful to prevent asthma as an anti-inflammatory treatment.

  16. Monte Carlo calculations and experimental measurements of dosimetric parameters of the IRA-103Pd brachytherapy source

    International Nuclear Information System (INIS)

    Sadeghi, Mahdi; Raisali, Gholamreza; Hosseini, S. Hamed; Shavar, Arzhang

    2008-01-01

    This article presents a brachytherapy source having 103 Pd adsorbed onto a cylindrical silver rod that has been developed by the Agricultural, Medical, and Industrial Research School for permanent implant applications. Dosimetric characteristics (radial dose function, anisotropy function, and anisotropy factor) of this source were experimentally and theoretically determined in terms of the updated AAPM Task group 43 (TG-43U1) recommendations. Monte Carlo simulations were used to calculate the dose rate constant. Measurements were performed using TLD-GR200A circular chip dosimeters using standard methods employing thermoluminescent dosimeters in a Perspex phantom. Precision machined bores in the phantom located the dosimeters and the source in a reproducible fixed geometry, providing for transverse-axis and angular dose profiles over a range of distances from 0.5 to 5 cm. The Monte Carlo N-particle (MCNP) code, version 4C simulation techniques have been used to evaluate the dose-rate distributions around this model 103 Pd source in water and Perspex phantoms. The Monte Carlo calculated dose rate constant of the IRA- 103 Pd source in water was found to be 0.678 cGy h -1 U -1 with an approximate uncertainty of ±0.1%. The anisotropy function, F(r,θ), and the radial dose function, g(r), of the IRA- 103 Pd source were also measured in a Perspex phantom and calculated in both Perspex and liquid water phantoms

  17. Effect of Small Intestine Strangulation Obstruction on Clinical and Histopathological Parameters An Experimental Study in Donkeys

    Directory of Open Access Journals (Sweden)

    Heba Mohamed M. Kuraa

    2011-06-01

    Full Text Available To study clinical and histopathological changes occur within the first 12 hours of strangulating obstruction of the small intestine in equine, twenty five adult donkeys were used in an experimental study. Strangulation obstruction of the small intestine was performed for 3, 6, 9 and 12 hours, respectively. Clinical examination was done before surgery and at 3 hours intervals postoperatively. After euthanasia, histopathological examination was made 10 cm, 1, 2 and 3 meters proximal to the strangulated part. Three hours postoperatively, the animals began to show signs of abdominal pain, they were looking around, stamping the hind feet, falling down suddenly. Nine hours postoperatively, animals showed signs of depression with intermittent nervous movements in the form of circle movement. After 12 hours, the animals were lying down; There were a significant reduction in the body temperature, respiratory rate, pulse rate, heart rate with significant increase in capillary refill time. Macroscopic changes of the strangulated part were congestion, edema, and dark red discoloration of the intestinal wall and mesentery. Distension of the intestine proximal to the strangulation extended more with increase the period of strangulation. Microscopic examination showed showed severe congestion, dark brown to blackish discoloration with fibrous shreds on the strangulated segment. Peticheal hemorrhages were observed in the intestinal wall and its mesentery for a distance up to 3 meters. The severity of signs varies according to the duration of obstruction which could give a remarkable justification of the prognosis of the patient and the availability of treatment.

  18. Evaluation of the low-level laser therapy application parameters for skin burn treatment in experimental model: a systematic review.

    Science.gov (United States)

    Brassolatti, Patricia; de Andrade, Ana Laura Martins; Bossini, Paulo Sérgio; Otterço, Albaiza Nicoletti; Parizotto, Nivaldo Antônio

    2018-05-05

    Burn is defined as a traumatic injury of thermal origin, which affects the organic tissue. Low-level laser therapy (LLLT) has gained great prominence as a treatment in this type of injury; however, the application parameters are still controversial in the literature. The aims of this study were to review the literature studies that use LLLT as a treatment in burns conducted in an experimental model, discuss the main parameters used, and highlight the benefits found in order to choose an appropriate therapeutic window to be applied in this type of injury. The selection of the studies related to the theme was carried out in the main databases (PubMed, Cochrane Library, LILACS, Web of Science, and Scopus in the period from 2001 to 2017). Subsequently, the articles were then chosen that fell within the inclusion criteria previously established. In the end, 22 were evaluated, and the main parameters were presented. The analyzed studies presented both LLLT use in continuous and pulsed mode. Differences between the parameters used (power, fluence, and total energy) were observed. In addition, the protocols are distinct as to the type of injury and the number of treatment sessions. Among the results obtained by the authors are the improvements in the local microcirculation and cellular proliferation; however, a study reported no effects with LLLT as a treatment. LLLT is effective in accelerating the healing process. However, there is immense difficulty in establishing the most adequate protocol, due to the great discrepancy found in the applied dosimetry values.

  19. Influence of a productive solution of uranium on some biochemical parameters of blood of an organism at experimental animals

    International Nuclear Information System (INIS)

    Svambaev, Z.A.; Svambaev, E.A.; Sultanbekov, G.A; Tusupbekova, S.T.

    2010-01-01

    In the work authors inform results on studying influence of a productive solution of uranium on some biochemical parameters of blood of an organism at experimental animals. It is established that all samples of a productive solution of uranium possesses high toxicity and causes destruction of experimental animals with infringement of a picture of blood. Experiments on influence on biochemical and hematology defined parameters of blood on chickens - broilers and on which female quails from daily age raised on cellular batteries in communities on 50 heads in conditions adequate to the requirement. Fed in plenty with the dry forages prepared according to 'Recommendations on the normalized feeding an agricultural bird' (1996), recipes 5-2; 6-1. To chickens in plenty allowed water from auto drinking bowls. Conditions of a micro climate corresponded to hygienic requirements. At carrying out of experiences studied the following parameters: preservation of a livestock, the reason of a withdrawal, weight of a body - weekly up to the end of experience, consumption of a forage, an expense of a forage for 1 kg of a gain have established weight of a body the methods standard in poultry farming. After application of a productive solution took blood from under wings of a vein and in blood have established maintenance of hemoglobin, quantity of red cells, leukocytes and a leukocyte of the formula, the maintenance of calcium and phosphorus. An application of a productive solution for experimental birds for the fifth day has caused clinical symptoms of a poisoning and destruction in groups. At the survived birds in blood it has been established changes biochemical and hematology. Week age chickens of skilled group lagged behind in growth development in comparison with control group on 30 % and at the end of the skilled period skilled have lagged behind in growth and development on 62 %. Among a livestock of chickens of skilled group of a case was more on 53 % on comparisons with the

  20. Parameter design and experimental study of a bifunctional isolator for optical payload protection and stabilization

    Science.gov (United States)

    Wang, Guang-yuan; Guan, Xin; Cao, Dong-jing; Tang, Shao-fan; Chen, Xiang; Liang, Lu; Zheng, Gang-tie

    2017-11-01

    requirement and the displacement restriction during launch are satisfied by tuning the nonlinear stiffness and damping parameters. A group of sample isolators are designed tested both statically and dynamically.

  1. Evaluation of DOE radionuclide solubility data and selected retardation parameters: description of calculational and confirmatory experimental activities

    International Nuclear Information System (INIS)

    Kelmers, A.D.; Clark, R.J.; Cutshall, N.H.; Johnson, J.S.; Kessler, J.H.

    1983-01-01

    An experimentally oriented program has been initiated to support the NRC analysis and licensing activities related to high-level nuclear waste repositories. The program will allow the NRC to independently confirm key geochemical values used in the site performance assessments submitted by the DOE candidate repository site projects. Key radionuclide retardation factor values, particularly radionuclide solubility and sorption values under site specific geochemical conditions, are being confirmed. The initial efforts are being directed toward basalt rock/groundwater systems relevant to the BWIP candidate site in the Pasco Basin. Future work will consider tuff (NNWSI candidate site in Yucca Mountain) and salt (unspecified ONWI bedded or domal salt sites) rock/groundwater systems. Initial experimental results with technetium have confirmed the BWIP values for basalt/groundwater systems under oxic redox conditions: high solubility and no sorption. Under reducing redox conditions, however, the experimental work did not confirm the proposed technetium values recommended by BWIP. In the presence of hydrazine to establish reducing conditions, an apparent solubility limit for technetium of about 5E-7 mol/L was encountered; BWIP recommended calculated values of 1E-12 or greater than or equal to 1E-14 mol/L. Experimental evidence concerning sorption of reduced technetium species is incomplete at this time. Equilibrium speciation and saturation indices were calculated for well water data sets from BWIP using the computer code PHREEQUE. Oversaturation was indicated for hematite and quartz in all data sets. Near surface samples were undersaturated with respect to calcite, but most deep samples were oversaturated with respect to calcite and other carbonate minerals

  2. Experimental parameters optimization of instrumental neutron activation analysis in order to determine selected elements in some industrial soils in Turkey

    International Nuclear Information System (INIS)

    Haciyakupoglu, Sevilay; Nur Esen, Ayse; Erenturk, Sema

    2014-01-01

    The purpose of this study is optimization of the experimental parameters for analysis of soil matrix by instrumental neutron activation analysis and quantitative determination of barium, cerium, lanthanum, rubidium, scandium and thorium in soil samples collected from industrialized urban areas near Istanbul. Samples were irradiated in TRIGA MARK II Research Reactor of Istanbul Technical University. Two types of reference materials were used to check the accuracy of the applied method. The achieved results were found to be in compliance with certified values of the reference materials. The calculated E n numbers for mentioned elements were found to be less than 1. The presented data of element concentrations in soil samples will help to trace the pollution as an impact of urbanization and industrialization, as well as providing database for future studies. - Highlights: • Optimization of experimental parameters is important for high sensitivity results by INAA. • Assessment of uncertainty sources is necessary to increase reliability of results. • The aim of this study is to determine a number of elements in industrial soil samples. • The higher concentrations of studied elements are due to rapid industrialization. • This baseline data can be used in future studies for other industrial areas

  3. Dissociation coefficients of protein adsorption to nanoparticles as quantitative metrics for description of the protein corona: A comparison of experimental techniques and methodological relevance

    KAUST Repository

    Hü hn, Jonas; Fedeli, Chiara; Zhang, Qian; Masood, Atif; del Pino, Pablo; Khashab, Niveen M.; Papini, Emanuele; Parak, Wolfgang J.

    2015-01-01

    Protein adsorption to nanoparticles is described as a chemical reaction in which proteins attach to binding sites on the nanoparticle surface. This process can be described with a dissociation coefficient, which tells how many proteins are adsorbed per nanoparticle in dependence of the protein concentration. Different techniques to experimentally determine dissociation coefficients of protein adsorption to nanoparticles are reviewed. Results of more than 130 experiments in which dissociation coefficients have been determined are compared. Data show that different methods, nanoparticle systems, and proteins can lead to significantly different dissociation coefficients. However, we observed a clear tendency of smaller dissociation coefficients upon less negative towards more positive zeta potentials of the nanoparticles. The zeta potential thus is a key parameter influencing protein adsorption to the surface of nanoparticles. Our analysis highlights the importance of the characterization of the parameters governing protein-nanoparticle interaction for quantitative evaluation and objective literature comparison.

  4. Dissociation coefficients of protein adsorption to nanoparticles as quantitative metrics for description of the protein corona: A comparison of experimental techniques and methodological relevance

    KAUST Repository

    Hühn, Jonas

    2015-12-31

    Protein adsorption to nanoparticles is described as a chemical reaction in which proteins attach to binding sites on the nanoparticle surface. This process can be described with a dissociation coefficient, which tells how many proteins are adsorbed per nanoparticle in dependence of the protein concentration. Different techniques to experimentally determine dissociation coefficients of protein adsorption to nanoparticles are reviewed. Results of more than 130 experiments in which dissociation coefficients have been determined are compared. Data show that different methods, nanoparticle systems, and proteins can lead to significantly different dissociation coefficients. However, we observed a clear tendency of smaller dissociation coefficients upon less negative towards more positive zeta potentials of the nanoparticles. The zeta potential thus is a key parameter influencing protein adsorption to the surface of nanoparticles. Our analysis highlights the importance of the characterization of the parameters governing protein-nanoparticle interaction for quantitative evaluation and objective literature comparison.

  5. Experimental Study of Direct Laser Deposition of Ti-6Al-4V and Inconel 718 by Using Pulsed Parameters

    Directory of Open Access Journals (Sweden)

    Kamran Shah

    2014-01-01

    Full Text Available Laser direct metal deposition (LDMD has developed from a prototyping to a single metal manufacturing tool. Its potential for creating multimaterial and functionally graded structures is now beginning to be explored. This work is a first part of a study in which a single layer of Inconel 718 is deposited on Ti-6Al-4V substrate. Single layer tracks were built at a range of powder mass flow rates using a coaxial nozzle and 1.5 kW diode laser operating in both continuous and pulsed beam modes. This part of the study focused on the experimental findings during the deposition of Inconel 718 powder on Ti-6Al-4V substrate. Scanning electron microscopy (SEM and X-ray diffraction analysis were performed for characterization and phase identification. Residual stress measurement had been carried out to ascertain the effects of laser pulse parameters on the crack development during the deposition process.

  6. Determination of heat transfer parameters by use of finite integral transform and experimental data for regular geometric shapes

    Science.gov (United States)

    Talaghat, Mohammad Reza; Jokar, Seyyed Mohammad

    2017-12-01

    This article offers a study on estimation of heat transfer parameters (coefficient and thermal diffusivity) using analytical solutions and experimental data for regular geometric shapes (such as infinite slab, infinite cylinder, and sphere). Analytical solutions have a broad use in experimentally determining these parameters. Here, the method of Finite Integral Transform (FIT) was used for solutions of governing differential equations. The temperature change at centerline location of regular shapes was recorded to determine both the thermal diffusivity and heat transfer coefficient. Aluminum and brass were used for testing. Experiments were performed for different conditions such as in a highly agitated water medium ( T = 52 °C) and in air medium ( T = 25 °C). Then, with the known slope of the temperature ratio vs. time curve and thickness of slab or radius of the cylindrical or spherical materials, thermal diffusivity value and heat transfer coefficient may be determined. According to the method presented in this study, the estimated of thermal diffusivity of aluminum and brass is 8.395 × 10-5 and 3.42 × 10-5 for a slab, 8.367 × 10-5 and 3.41 × 10-5 for a cylindrical rod and 8.385 × 10-5 and 3.40 × 10-5 m2/s for a spherical shape, respectively. The results showed there is close agreement between the values estimated here and those already published in the literature. The TAAD% is 0.42 and 0.39 for thermal diffusivity of aluminum and brass, respectively.

  7. SU-E-J-166: Sensitivity of Clinically Relevant Dosimetric Parameters to Contouring Uncertainty During Post Implant Dosimetry of Prostate Permanent Seed Implants

    Energy Technology Data Exchange (ETDEWEB)

    Mashouf, S [Sunnybrook Odette Cancer Centre, Toronto, ON (Canada); University of Toronto, Dept. of Radiation Oncology, Toronto, ON (Canada); Ravi, A; Morton, G; Song, W [Sunnybrook Odette Cancer Centre, Toronto, ON (Canada); University of Toronto, Dept. of Radiation Oncology, Toronto, ON (Canada); Sunnybrook Research Institute, Toronto, ON (Canada)

    2015-06-15

    Purpose: There is a strong evidence relating post-implant dosimetry for permanent seed prostate brachytherpy to local control rates. The delineation of the prostate on CT images, however, represents a challenge as it is difficult to confidently identify the prostate borders from soft tissue surrounding it. This study aims at quantifying the sensitivity of clinically relevant dosimetric parameters to prostate contouring uncertainty. Methods: The post-implant CT images and plans for a cohort of 43 patients, who have received I–125 permanent prostate seed implant in our centre, were exported to MIM Symphony LDR brachytherapy treatment planning system (MIM Software Inc., Cleveland, OH). The prostate contours in post-implant CT images were expanded/contracted uniformly for margins of ±1.00mm, ±2.00mm, ±3.00mm, ±4.00mm and ±5.00mm (±0.01mm). The values for V100 and D90 were extracted from Dose Volume Histograms for each contour and compared. Results: The mean value of V100 and D90 was obtained as 92.3±8.4% and 108.4±12.3% respectively (Rx=145Gy). V100 was reduced by −3.2±1.5%, −7.2±3.0%, −12.8±4.0%, −19.0±4.8%, − 25.5±5.4% for expanded contours of prostate with margins of +1mm, +2mm, +3mm, +4mm, and +5mm, respectively, while it was increased by 1.6±1.2%, 2.4±2.4%, 2.7±3.2%, 2.9±4.2%, 2.9±5.1% for the contracted contours. D90 was reduced by −6.9±3.5%, −14.5±6.1%, −23.8±7.1%, − 33.6±8.5%, −40.6±8.7% and increased by 4.1±2.6%, 6.1±5.0%, 7.2±5.7%, 8.1±7.3% and 8.1±7.3% for the same set of contours. Conclusion: Systematic expansion errors of more than 1mm may likely render a plan sub-optimal. Conversely contraction errors may Result in labeling a plan likely as optimal. The use of MRI images to contour the prostate should results in better delineation of prostate organ which increases the predictive value of post-op plans. Since observers tend to overestimate the prostate volume on CT, compared with MRI, the impact of the

  8. Experimental investigation and optimization of welding process parameters for various steel grades using NN tool and Taguchi method

    Science.gov (United States)

    Soni, Sourabh Kumar; Thomas, Benedict

    2018-04-01

    The term "weldability" has been used to describe a wide variety of characteristics when a material is subjected to welding. In our analysis we perform experimental investigation to estimate the tensile strength of welded joint strength and then optimization of welding process parameters by using taguchi method and Artificial Neural Network (ANN) tool in MINITAB and MATLAB software respectively. The study reveals the influence on weldability of steel by varying composition of steel by mechanical characterization. At first we prepare the samples of different grades of steel (EN8, EN 19, EN 24). The samples were welded together by metal inert gas welding process and then tensile testing on Universal testing machine (UTM) was conducted for the same to evaluate the tensile strength of the welded steel specimens. Further comparative study was performed to find the effects of welding parameter on quality of weld strength by employing Taguchi method and Neural Network tool. Finally we concluded that taguchi method and Neural Network Tool is much efficient technique for optimization.

  9. DEM modeling of ball mills with experimental validation: influence of contact parameters on charge motion and power draw

    Science.gov (United States)

    Boemer, Dominik; Ponthot, Jean-Philippe

    2017-01-01

    Discrete element method simulations of a 1:5-scale laboratory ball mill are presented in this paper to study the influence of the contact parameters on the charge motion and the power draw. The position density limit is introduced as an efficient mathematical tool to describe and to compare the macroscopic charge motion in different scenarios, i.a. with different values of the contact parameters. While the charge motion and the power draw are relatively insensitive to the stiffness and the damping coefficient of the linear spring-slider-damper contact law, the coefficient of friction has a strong influence since it controls the sliding propensity of the charge. Based on the experimental calibration and validation by charge motion photographs and power draw measurements, the descriptive and predictive capabilities of the position density limit and the discrete element method are demonstrated, i.e. the real position of the charge is precisely delimited by the respective position density limit and the power draw can be predicted with an accuracy of about 5 %.

  10. Determining experimentally the parameters of the unsteady thermal behaviour of homogeneously layered walls by the reference plates method

    International Nuclear Information System (INIS)

    Beron, Rodolphe

    1988-01-01

    In this work, we introduce an experimental determination method of parameters which are characteristics of the transfer functions of walls in buildings by the use of an easy equipment which use needs no significant constraint. This method called 'reference plates method' is based on the working out of the thermo-grams which result from any thermal perturbation. The first part of our work deals with the theoretical development of the methods of working out the measures used for both single-Iayered and multi-layered walls. The second part discusses the applying of the method on single-Iayered sample. The values of thermophysical characteristics of the wall is based on the working out of the heat equation written in terms an integral transformation which we take as Laplace's transformation. The case of multi-Iayered wall which we discuss in the third part, lead to the determination of 'z transforms coefficients' of the transfer functions of the studied wall. In addition to the theoretical study, we analyse the results of prospective experiments in the fourth part of our work and show the usefulness of such a measurement method. The last part is devoted to the presentation of the application of our work to the determination of thermal parameters of more general wall's configurations. (author) [fr

  11. Experimental Investigation on the Fatigue Mechanical Properties of Intermittently Jointed Rock Models Under Cyclic Uniaxial Compression with Different Loading Parameters

    Science.gov (United States)

    Liu, Yi; Dai, Feng; Dong, Lu; Xu, Nuwen; Feng, Peng

    2018-01-01

    Intermittently jointed rocks, widely existing in many mining and civil engineering structures, are quite susceptible to cyclic loading. Understanding the fatigue mechanism of jointed rocks is vital to the rational design and the long-term stability analysis of rock structures. In this study, the fatigue mechanical properties of synthetic jointed rock models under different cyclic conditions are systematically investigated in the laboratory, including four loading frequencies, four maximum stresses, and four amplitudes. Our experimental results reveal the influence of the three cyclic loading parameters on the mechanical properties of jointed rock models, regarding the fatigue deformation characteristics, the fatigue energy and damage evolution, and the fatigue failure and progressive failure behavior. Under lower loading frequency or higher maximum stress and amplitude, the jointed specimen is characterized by higher fatigue deformation moduli and higher dissipated hysteresis energy, resulting in higher cumulative damage and lower fatigue life. However, the fatigue failure modes of jointed specimens are independent of cyclic loading parameters; all tested jointed specimens exhibit a prominent tensile splitting failure mode. Three different crack coalescence patterns are classified between two adjacent joints. Furthermore, different from the progressive failure under static monotonic loading, the jointed rock specimens under cyclic compression fail more abruptly without evident preceding signs. The tensile cracks on the front surface of jointed specimens always initiate from the joint tips and then propagate at a certain angle with the joints toward the direction of maximum compression.

  12. Detection of angiogenesis-dependent parameters by functional MRI: Correlation between histomorphology and evaluation of clinical relevance as prognostic factor for the example of cervical carcinoma

    International Nuclear Information System (INIS)

    Hawighorst, H.; Knopp, M.V.; Schoenberg, S.O.; Essig, M.; Kaick, G. van; Schaeffer, U.; Knapstein, P.G.; Weikel, W.

    1998-01-01

    Purpose: Purpose of this study is to compare functional MRI parameters with histomorphological markers of tumor microvessel density (MVD) and permeability (vascular endothelial growth factor) and to determine the ultimate value of both approaches by correlation with disease outcome in patients with primary cancer of the uterine cervix. Method: Pharmacokinetic parameters were calculated from contrast-enhanced dynamic MR imaging series in 37 patients with biopsy-proven primary cervical cancer. On the operative whole mount specimens, histomorphological markers of tumor angiogenesis (MVD, VEGF) were compared with the MRI-derived parameters. For MRI and histomorphological data, Kaplan-Meier survival curves were calculated and compared using logrank statistics. Results: Significant (p [de

  13. Characterization of an erbium doped fiber amplifier starting from its experimental parameters; Caracterizacion de un amplificador de fibra dopada con erbio a partir de sus parametros experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Bello J, M.; Kuzin, E.A.; Ibarra E, B. [Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Luis Enrique Erro No. 1, TonantzintIa, 72000 Puebla (Mexico); Tellez G, R. [Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No 152, Delegacion Gustavo A. Madero, 07730 Mexico D.F. (Mexico)]. e-mail: mabello@inaoep.mx

    2007-07-01

    In this paper we describe a method to characterize the gain of an erbium-doped fiber amplifier (EDFA) through the numerical simulation of the signal beam along the amplifier. The simulation is based on a model constituted by the propagation and rate equations for an erbium-doped fiber. The manipulation of these equations allows us to regroup the parameters present in an EDFA, which we have named the A, B, C, D parameters, and they can be obtained experimentally from an erbium-doped fiber. Experimental results show that the measurement of these parameters allow us to estimate with very good correspondence the amplifier gain. (Author)

  14. An analytical and experimental approach for pressure distribution analysis of a particular lobe and plain bearing performance keeping in view of all impeding varying parameters associating with fixed lubrication SAE20W40

    International Nuclear Information System (INIS)

    Biswas, Nabarun; Chakraborti, Prasun; Belkar, Sanjay

    2016-01-01

    This paper presents both analytical and experimental pressure analysis approach of a typical Lobe and plain bearing for determining effective performance of the bearing. This is found to be dependent on several variables viz. angular velocity (1200-1900 rpm), load (300- 750 N) and pressure angle (0.deg.-180.deg.). This study in particular has been carried out for better rectifications and comparative prediction of lobe and plain bearing in terms of pressure distribution behavior under lubrication oil grade of SAE20W40. Influencing parameters were varied in this set up only to get optimum parametric combination considering all relevant practical issues. The experimentation was done based on significant directives of relevant literatures in these sectors. Attempt was made to compare the analytical findings with experimental results and found matched appreciably. After that attention was diverted to find the nature of pressure and load carrying capacity at various fluctuating speed and load with a fixed lubrication of SAE20W40 for appropriate decision making towards its characteristic performance. The analytical data generated by MATLAB are compared with experimental data which is generated by JBTR

  15. An analytical and experimental approach for pressure distribution analysis of a particular lobe and plain bearing performance keeping in view of all impeding varying parameters associating with fixed lubrication SAE20W40

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Nabarun; Chakraborti, Prasun [National Institute of Technology Agartala, Jirania (India); Belkar, Sanjay [Pravara Rural Engineering CollegeLoni, Rahata taluka (India)

    2016-05-15

    This paper presents both analytical and experimental pressure analysis approach of a typical Lobe and plain bearing for determining effective performance of the bearing. This is found to be dependent on several variables viz. angular velocity (1200-1900 rpm), load (300- 750 N) and pressure angle (0.deg.-180.deg.). This study in particular has been carried out for better rectifications and comparative prediction of lobe and plain bearing in terms of pressure distribution behavior under lubrication oil grade of SAE20W40. Influencing parameters were varied in this set up only to get optimum parametric combination considering all relevant practical issues. The experimentation was done based on significant directives of relevant literatures in these sectors. Attempt was made to compare the analytical findings with experimental results and found matched appreciably. After that attention was diverted to find the nature of pressure and load carrying capacity at various fluctuating speed and load with a fixed lubrication of SAE20W40 for appropriate decision making towards its characteristic performance. The analytical data generated by MATLAB are compared with experimental data which is generated by JBTR.

  16. Theory and experimental verifications of the resonator Q and equivalent electrical parameters due to viscoelastic and mounting supports losses.

    Science.gov (United States)

    Yong, Yook-Kong; Patel, Mihir S; Tanaka, Masako

    2010-08-01

    A novel analytical/numerical method for calculating the resonator Q and its equivalent electrical parameters due to viscoelastic, conductivity, and mounting supports losses is presented. The method presented will be quite useful for designing new resonators and reducing the time and costs of prototyping. There was also a necessity for better and more realistic modeling of the resonators because of miniaturization and the rapid advances in the frequency ranges of telecommunication. We present new 3-D finite elements models of quartz resonators with viscoelasticity, conductivity, and mounting support losses. The losses at the mounting supports were modeled by perfectly matched layers (PMLs). A previously published theory for dissipative anisotropic piezoelectric solids was formulated in a weak form for finite element (FE) applications. PMLs were placed at the base of the mounting supports to simulate the energy losses to a semi-infinite base substrate. FE simulations were carried out for free vibrations and forced vibrations of quartz tuning fork and AT-cut resonators. Results for quartz tuning fork and thickness shear AT-cut resonators were presented and compared with experimental data. Results for the resonator Q and the equivalent electrical parameters were compared with their measured values. Good equivalences were found. Results for both low- and high-Q AT-cut quartz resonators compared well with their experimental values. A method for estimating the Q directly from the frequency spectrum obtained for free vibrations was also presented. An important determinant of the quality factor Q of a quartz resonator is the loss of energy from the electrode area to the base via the mountings. The acoustical characteristics of the plate resonator are changed when the plate is mounted onto a base substrate. The base affects the frequency spectra of the plate resonator. A resonator with a high Q may not have a similarly high Q when mounted on a base. Hence, the base is an

  17. Experimental Investigation of Process Parameters in Drilling LM25 Composites Coated with Multi Wall Carbon Nano Tubes Using Sonication Process

    Directory of Open Access Journals (Sweden)

    Sangeetha M.

    2017-09-01

    Full Text Available Aluminium based metal matrix composites are widely used in automobile components such as cardan shaft of Chevrolet corvette, disc brake and engine push rod. In this experiment a Hybrid Metal Matrix Composites (HMMC are fabricated and drilled. Drilling is the process of making slots in disc brake and thread in the engine parts. The surface quality of the drilled specimen depends on the speed, feed, drill type and the thrust force. Thrust force plays the major role in drilling the specimen. In this experiment HMMCs are fabricated using two processes-called, sonication and casting. Sonication is the process of coating the carbon nanotubes over the silicon carbide particles (SiCp. Semisolid stir casting is used to reinforce the coated SiCp in the LM 25 alloy. A drilling process is performed on HMMC to analyse the extent to which the input parameters influence the thrust force and Ovality. The tools used for drilling are solid carbide tools of three different diameters. Taguchi’s experimental design is adopted for the drilling operation. A mathematical model is used to determine the influence of input parameters on the outputs thrust force and ovality. This paper proves the combination of N3, f1 and d1 of the carbide tool results in the lowest value of thrust force and ovality while drilling HMMCs. In this work the HMMC is prepared by coating the abrasive nature, silicon carbide particle and there is a good interfacial bonding between the reinforced particle and matrix and the drilling process becomes smoother. The new being of this article is the treated ceramics, SiCp with carbon nanotubes. This HMMC shows the improved mechanical properties compared to other metal matrix composites surveyed in the literatures.

  18. An experimental hut study to quantify the effect of DDT and airborne pyrethroids on entomological parameters of malaria transmission

    Science.gov (United States)

    2014-01-01

    Background Current malaria vector control programmes rely on insecticides with rapid contact toxicity. However, spatial repellents can also be applied to reduce man-vector contact, which might ultimately impact malaria transmission. The aim of this study was to quantify effects of airborne pyrethroids from coils and DDT used an indoor residual spray (IRS) on entomological parameters that influence malaria transmission. Methods The effect of Transfluthrin and Metofluthrin coils compared to DDT on house entry, exit and indoor feeding behaviour of Anopheles gambiae sensu lato were measured in experimental huts in the field and in the semi-field. Outcomes were deterrence - reduction in house entry of mosquitoes; irritancy or excito-repellency – induced premature exit of mosquitoes; blood feeding inhibition and effect on mosquito fecundity. Results Transfluthrin coils, Metofluthrin coils and DDT reduced human vector contact through deterrence by 38%, 30% and 8%, respectively and induced half of the mosquitoes to leave huts before feeding (56%, 55% and 48%, respectively). Almost all mosquitoes inside huts with Metofluthrin and Transfluthrin coils and more than three quarters of mosquitoes in the DDT hut did not feed, almost none laid eggs and 67%, 72% and 70% of all mosquitoes collected from Transfluthrin, Metofluthrin and DDT huts, respectively had died after 24 hours. Conclusion This study highlights that airborne pyrethroids and DDT affect a range of anopheline mosquito behaviours that are important parameters in malaria transmission, namely deterrence, irritancy/excito-repellency and blood-feeding inhibition. These effects are in addition to significant toxicity and reduced mosquito fecundity that affect mosquito densities and, therefore, provide community protection against diseases for both users and non-users. Airborne insecticides and freshly applied DDT had similar effects on deterrence, irritancy and feeding inhibition. Therefore, it is suggested that

  19. An experimental hut study to quantify the effect of DDT and airborne pyrethroids on entomological parameters of malaria transmission.

    Science.gov (United States)

    Ogoma, Sheila B; Lorenz, Lena M; Ngonyani, Hassan; Sangusangu, Robert; Kitumbukile, Mohammed; Kilalangongono, Masoudi; Simfukwe, Emmanuel T; Mseka, Anton; Mbeyela, Edgar; Roman, Deogratius; Moore, Jason; Kreppel, Katharina; Maia, Marta F; Moore, Sarah J

    2014-04-01

    Current malaria vector control programmes rely on insecticides with rapid contact toxicity. However, spatial repellents can also be applied to reduce man-vector contact, which might ultimately impact malaria transmission. The aim of this study was to quantify effects of airborne pyrethroids from coils and DDT used an indoor residual spray (IRS) on entomological parameters that influence malaria transmission. The effect of Transfluthrin and Metofluthrin coils compared to DDT on house entry, exit and indoor feeding behaviour of Anopheles gambiae sensu lato were measured in experimental huts in the field and in the semi-field. Outcomes were deterrence--reduction in house entry of mosquitoes; irritancy or excito-repellency--induced premature exit of mosquitoes; blood feeding inhibition and effect on mosquito fecundity. Transfluthrin coils, Metofluthrin coils and DDT reduced human vector contact through deterrence by 38%, 30% and 8%, respectively and induced half of the mosquitoes to leave huts before feeding (56%, 55% and 48%, respectively). Almost all mosquitoes inside huts with Metofluthrin and Transfluthrin coils and more than three quarters of mosquitoes in the DDT hut did not feed, almost none laid eggs and 67%, 72% and 70% of all mosquitoes collected from Transfluthrin, Metofluthrin and DDT huts, respectively had died after 24 hours. This study highlights that airborne pyrethroids and DDT affect a range of anopheline mosquito behaviours that are important parameters in malaria transmission, namely deterrence, irritancy/excito-repellency and blood-feeding inhibition. These effects are in addition to significant toxicity and reduced mosquito fecundity that affect mosquito densities and, therefore, provide community protection against diseases for both users and non-users. Airborne insecticides and freshly applied DDT had similar effects on deterrence, irritancy and feeding inhibition. Therefore, it is suggested that airborne pyrethroids, if delivered in suitable

  20. Gadolinium as a CT contrast agent: an experimental study for the effects of injection parameters in the rabbit brain model

    International Nuclear Information System (INIS)

    Kim, Hyun Jin; Choi, Hye Young; Lee, Sun Wha; Hwang, Ji Young

    2005-01-01

    We wanted to investigate the use of gadolinium based contrast agent (Gd-DTPA) for computed tomography (CT), and we also wanted to assess the effects of valuable injection parameters on enhancement in an experimental rabbit brain model. In vitro, attenuation measurements of serial dilutions of Gd-DTPA and iopromide were compared. In five rabbits, single level dynamic gadolinium-enhanced brain CT studies were obtained using different injection parameters. A comparision CT scan after iopromide administration was performed. The time-attenuation curves of the brain vessel and parenchyma were obtained and the magnitude of enhancement (Hmax) and the time to peak enhancement (Tmax) were analyzed. In vitro, the attenuation coefficient of undiluted Gd-DTPA (2,578 HU) was higher than that of iopromide (1,761 HU) at equimolar concentrations. In 5 rabbits, the time-attenuation curve demonstrated a distinct pattern with peak enhancement only in the brain vessel, but not in the brain parenchyma. There was increasing linear relationship between the injection rate of Gd-DTPA and Hmax, and a declining linear relationship with Tmax. The higher the concentration of Gd-DTPA, the higher Hmax was, but no significant difference was found for the Tmax. Higher volumes of Gd-DTPA revealed a higher Hmax and a delayed Tmax. Enhancement of the brain parenchyma on gadolinium-enhanced CT is minimal, while enhancement of the brain vessels is distinctive. The most important factor affecting Hmax of the vessel is the concentration of the contrast medium and the most important factor affecting Tmax of the vessel is volume of the contrast medium. The gadolinium-based contrast agent may be an reasonable alternative contrast agent for brain CT, and especially in cerebral vessels, and it may also be advantageous for brain parenchyma of those patients with BBB dysfunction

  1. Blood culture as a parameter of treatment effectiveness in experimental histoplasmosis of the hamster Hemocultivos como parametro de la eficacia del tratamiento de la histoplasmosis experimental en hamster

    Directory of Open Access Journals (Sweden)

    J. Finquelievich

    1995-04-01

    Full Text Available The aim of this study was to determine the value of blood culture as a parameter of treatment effectiveness in experimental histoplasmosis. A total of thirty five hamsters, weighing approximately 120g, were inoculated intracardiacly with 0.1 ml of a suspension containing 4 x 10(7 cells/ml of the yeast phase of H. capsulatum. Treatments were started one week after the infection and lasted for 3 weeks. The azoles, (itraconazole, saperconazole and fluconazole were administered once a day by gavage, at a dose of 8 mg/kg; Amphotericin B was given intraperitonealy every other day at a dose of 6mg/kg. Blood samples (1 ml were obtained by heart punction from the 4th day after infection and were seeded in Sabouraud honey-agar and BHI-agar. The hamsters that survived were killed one week after treatment completion and the following criteria were considered for treatment evaluation: 1 rate of spontaneous death, at the end of the experience; 2 microscopic examination of Giemsa smears from liver and spleen and 3 determination of CFU in spleen cultures. Amphotericin B was the most effective drug, with negative blood cultures at day 20, negative spleen cultures in all cases and all the animals survived until the end of the study. Fluconazole was the less effective drug, blood cultures were positive during the whole experience, spleen cultures showed a similar average of CFU when compared with the control animals and 42.8% of these animals died. Saperconazole and itraconazole showed a similar activity, with survival of all hamsters and negative blood cultures at 23 and 26 days respectively. Blood culture seems to be valuable parameter for treatments' evaluation in experimental histoplasmosis of the hamster.El propósito de esta investigación fue determinar el valor de los hemocultivos para juzgar la eficacia de los tratamientos en la histoplasmosis experimental. Treinta y cinco hamsters fueron inoculados por via intracardíaca con 0.1 ml de una suspensión de

  2. Theoretical and experimental research on the influence of multiple piezoelectric effects on physical parameters of piezoelectric actuator

    Directory of Open Access Journals (Sweden)

    Liping Shi

    2015-04-01

    Full Text Available Compared with the traditional actuator of machinery and electricity, the piezoelectric actuator has the advantages of a compact structure, small volume, no mechanical friction, athermancy and no electromagnetic interference. Therefore, it has high application value in the fields of MEMS, bioengineering, medical science and so on. This article draws conclusions from the influence of multiple piezoelectric effects on the physical parameters (dielectric coefficient, equivalent capacity, energy conversion and piezoelectric coefficient of piezoelectric actuators. These data from theoretical and experimental research show the following: (1 The rate between the dielectric coefficient of piezoelectric in mechanical freedom and clamping is obtained from the secondary direct piezoelectric effect, which enhances the dielectric property, increases the dielectric coefficient and decreases the coefficient of dielectric isolation; (2 Under external field, E n ( ex = E 1 , exterior stress T = 0, that is to say, under the boundary condition of mechanical freedom, piezoelectric can store electric energy and elasticity, which obtains power density, elastic density and an electromechanical coupling factor; (3 According to the piezoelectric strain S i ( 1 , piezoelectric displacement D m ( 2 and piezoelectric strain S i ( 3 of multiple piezoelectric effects, when the dielectric coefficient of the first converse piezoelectric effect ε33 is 1326 and the dielectric coefficient of the secondary direct piezoelectric effect increases to 3336, the dielectric coefficient of the ceramic chip increases. When the piezoelectric coefficient of the first converse piezoelectric effect d33 is 595 and the piezoelectric coefficient of the secondary direct piezoelectric effect decreases to 240, the piezoelectric coefficient of the ceramic chip will decrease. It is of major significance both in the applications and in basic theory to research the influence of multiple piezoelectric

  3. Influence of the operational parameters on bioelectricity generation in continuous microbial fuel cell, experimental and computational fluid dynamics modelling

    Science.gov (United States)

    Sobieszuk, Paweł; Zamojska-Jaroszewicz, Anna; Makowski, Łukasz

    2017-12-01

    The influence of the organic loading rate (also known as active anodic chamber volume) on bioelectricity generation in a continuous, two-chamber microbial fuel cell for the treatment of synthetic wastewater, with glucose as the only carbon source, was examined. Ten sets of experiments with different combinations of hydraulic retention times (0.24-1.14 d) and influent chemical oxygen demand concentrations were performed to verify the impact of organic loading rate on the voltage generation capacity of a simple dual-chamber microbial fuel cell working in continuous mode. We found that there is an optimal hydraulic retention time value at which the maximum voltage is generated: 0.41 d. However, there were no similar effects, in terms of voltage generation, when a constant hydraulic retention time with different influent chemical oxygen demand of wastewater was used. The obtained maximal voltage value (600 mV) has also been compared to literature data. Computational fluid dynamics (CFD) was used to calculate the fluid flow and the exit age distribution of fluid elements in the reactor to explain the obtained experimental results and identify the crucial parameters for the design of bioreactors on an industrial scale.

  4. An In Vitro Approach to Study Effects of Prebiotics and Probiotics on the Faecal Microbiota and Selected Immune Parameters Relevant to the Elderly.

    Science.gov (United States)

    Liu, Yue; Gibson, Glenn R; Walton, Gemma E

    2016-01-01

    The aging process leads to alterations of gut microbiota and modifications to the immune response, such changes may be associated with increased disease risk. Prebiotics and probiotics can modulate microbiome changes induced by aging; however, their effects have not been directly compared. The aim of this study was to use anaerobic batch culture fermenters to assess the impact of various fermentable carbohydrates and microorganisms on the gut microbiota and selected immune markers. Elderly volunteers were used as donors for these experiments to enable relevance to an aging population. The impact of fermentation supernatants on immune markers relevant to the elderly were assessed in vitro. Levels of IL-1β, IL-6, IL-8, IL-10 and TNF-α in peripheral blood mononuclear cell culture supernatants were measured using flow cytometry. Trans-galactooligosaccharides (B-GOS) and inulin both stimulated bifidobacteria compared to other treatments (pprebiotics and probiotics could lead to potentially beneficial effects to host health by targeting specific bacterial groups, increasing saccharolytic fermentation and decreasing inflammation associated with aging. Compared to probiotics, prebiotics led to greater microbiota modulation at the genus level within the fermenters.

  5. Analysis of water sorption isotherms of amorphous food materials by solution thermodynamics with relevance to glass transition: evaluation of plasticizing effect of water by the thermodynamic parameters.

    Science.gov (United States)

    Shimazaki, Eriko; Tashiro, Akiko; Kumagai, Hitomi; Kumagai, Hitoshi

    2017-04-01

    Relation between the thermodynamic parameters obtained from water sorption isotherms and the degree of reduction in the glass transition temperature (T g ), accompanied by water sorption, was quantitatively studied. Two well-known glassy food materials namely, wheat gluten and maltodextrin were used as samples. The difference between the chemical potential of water in a solution and that of pure water ([Formula: see text]), the difference between the chemical potential of solid in a solution and that of a pure solid ([Formula: see text]), and the change in the integral Gibbs free energy ([Formula: see text]) were obtained by analyzing the water sorption isotherms using solution thermodynamics. The parameter [Formula: see text] correlated well with ΔT g (≡T g  - T g0 ; where T g0 is the glass transition temperature of dry material), which had been taken to be an index of plasticizing effect. This indicates that plasticizing effect of water on foods can be evaluated through the parameter [Formula: see text].

  6. Design of a Data Catalogue for Perdigão-2017 Field Experiment: Establishing the Relevant Parameters, Post-Processing Techniques and Users Access

    Science.gov (United States)

    Palma, J. L.; Belo-Pereira, M.; Leo, L. S.; Fernando, J.; Wildmann, N.; Gerz, T.; Rodrigues, C. V.; Lopes, A. S.; Lopes, J. C.

    2017-12-01

    Perdigão is the largest of a series of wind-mapping studies embedded in the on-going NEWA (New European Wind Atlas) Project. The intensive observational period of the Perdigão field experiment resulted in an unprecedented volume of data, covering several wind conditions through 46 consecutive days between May and June 2017. For researchers looking into specific events, it is time consuming to scrutinise the datasets looking for appropriate conditions. Such task becomes harder if the parameters of interest were not measured directly, instead requiring their computation from the raw datasets. This work will present the e-Science platform developed by University of Porto for the Perdigao dataset. The platform will assist scientists of Perdigao and the larger scientific community in extrapolating the datasets associated to specific flow regimes of interest as well as automatically performing post-processing/filtering operations internally in the platform. We will illustrate the flow regime categories identified in Perdigao based on several parameters such as weather type classification, cloud characteristics, as well as stability regime indicators (Brunt-Väisälä frequency, Scorer parameter, potential temperature inversion heights, dimensionless Richardson and Froude numbers) and wind regime indicators. Examples of some of the post-processing techniques available in the e-Science platform, such as the Savitzky-Golay low-pass filtering technique, will be also presented.

  7. An In Vitro Approach to Study Effects of Prebiotics and Probiotics on the Faecal Microbiota and Selected Immune Parameters Relevant to the Elderly.

    Directory of Open Access Journals (Sweden)

    Yue Liu

    Full Text Available The aging process leads to alterations of gut microbiota and modifications to the immune response, such changes may be associated with increased disease risk. Prebiotics and probiotics can modulate microbiome changes induced by aging; however, their effects have not been directly compared. The aim of this study was to use anaerobic batch culture fermenters to assess the impact of various fermentable carbohydrates and microorganisms on the gut microbiota and selected immune markers. Elderly volunteers were used as donors for these experiments to enable relevance to an aging population. The impact of fermentation supernatants on immune markers relevant to the elderly were assessed in vitro. Levels of IL-1β, IL-6, IL-8, IL-10 and TNF-α in peripheral blood mononuclear cell culture supernatants were measured using flow cytometry. Trans-galactooligosaccharides (B-GOS and inulin both stimulated bifidobacteria compared to other treatments (p<0.05. Fermentation supernatants taken from faecal batch cultures supplemented with B-GOS, inulin, B. bifidum, L. acidophilus and Ba. coagulans inhibited LPS induced TNF-α (p<0.05. IL-10 production, induced by LPS, was enhanced by fermentation supernatants from faecal batch cultures supplemented with B-GOS, inulin, B. bifidum, L. acidophilus, Ba. coagulans and Bac. thetaiotaomicron (p<0.05. To conclude, prebiotics and probiotics could lead to potentially beneficial effects to host health by targeting specific bacterial groups, increasing saccharolytic fermentation and decreasing inflammation associated with aging. Compared to probiotics, prebiotics led to greater microbiota modulation at the genus level within the fermenters.

  8. Oral delivery of live yeast Debaryomyces hansenii modulates the main innate immune parameters and the expression of immune-relevant genes in the gilthead seabream (Sparus aurata L.).

    Science.gov (United States)

    Reyes-Becerril, Martha; Salinas, Irene; Cuesta, Alberto; Meseguer, José; Tovar-Ramirez, Dariel; Ascencio-Valle, Felipe; Esteban, Maria Angeles

    2008-12-01

    Microorganisms isolated from fish can be used as prophylactic tools for aquaculture in the form of probiotic preparations. The purpose of this study was to evaluate the effects of dietary administration of the live yeast Debaryomyces hansenii CBS 8339 on the gilthead seabream (Sparus aurata L.) innate immune responses. Seabream were fed control or D. hansenii-supplemented diets (10(6) colony forming units, CFU g(-1)) for 4 weeks. Humoral (seric alternative complement and peroxidase activities), and cellular (peroxidase, phagocytic, respiratory burst and cytotoxic activities) innate immune parameters and antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)) were measured from serum, head-kidney leucocytes and liver, respectively, after 2 and 4 weeks of feeding. Expression levels of immune-associated genes, Hep, IgM, TCR-beta, NCCRP-1, MHC-II alpha, CSF-1R, C3, TNF-alpha and IL-1 beta, were also evaluated by real-time PCR in head-kidney, liver and intestine. Humoral immune parameters were not significantly affected by the dietary supplementation of yeast at any time of the experiment. On the other hand, D. hansenii administration significantly enhanced leucocyte peroxidase and respiratory burst activity at week 4. Phagocytic and cytotoxic activities had significantly increased by week 2 of feeding yeast but unchanged by week 4. A significant increase in liver SOD activity was observed at week 2 of feeding with the supplemented diet; however CAT activity was not affected by the dietary yeast supplement at any time of the experiment. Finally, the yeast supplemented diet down-regulated the expression of most seabream genes, except C3, in liver and intestine and up-regulated all of them in the head-kidney. These results strongly support the idea that live yeast Debaryomyces hansenii strain CBS 8339 can stimulate the innate immune parameters in seabream, especially at cellular level.

  9. Effects of isolated vitamin B6 supplementation on oxidative stress and heart function parameters in experimental hyperhomocysteinemia

    Directory of Open Access Journals (Sweden)

    Roberta Hack Mendes

    2017-07-01

    Full Text Available Introduction: The purpose of this study was to investigate the effects of isolated vitamin B6 (VB6 supplementation on experimental hyperhomocysteinemia (Hhe induced by homocysteine thiolactone (HcyT. Methods: Fifteen male Wistar rats were divided into three groups according to their treatment. Animals received water and food ad libitum and an intragastric probe was used to administer water for 60 days (groups: CB6, HcyT, and HB6. On the 30th day of treatment, two groups were supplemented with VB6 in the drinking water (groups: CB6 and HB6. After 60 days of treatment, homocysteine (Hcy, cysteine, and hydrogen peroxide concentration, nuclear factor (erythroid-derived 2-like 2 (NRF2 and glutathione S-transferase (GST immunocontent, and superoxide dismutase (SOD, catalase (CAT, and GST activities were measured. Results: The HcyT group showed an increase in Hcy concentration (62% in relation to the CB6 group. Additionally, GST immunocontent was enhanced (51% in the HB6 group compared to the HcyT group. Also, SOD activity was lower (17% in the HB6 group compared to the CB6 group, and CAT activity was higher in the HcyT group (53% compared to the CB6 group. Ejection fraction (EF was improved in the HB6 group compared to the HcyT group. E/A ratio was enhanced in the HB6 group compared to the CB6 group. Correlations were found between CAT activity with myocardial performance index (MPI (r = 0.71; P = 0.06 and E/A ratio (r = 0.6; P = 0.01, and between EF and GST activity (r = 0.62; P = 0.02. Conclusions: These findings indicate that isolated VB6 supplementation may lead to the reduction of Hcy concentration and promotes additional benefits to oxidative stress and heart function parameters.   Keywords: Homocysteine; oxidative stress; vitamin B6.

  10. Final Report for NFE-07-00912: Development of Model Fuels Experimental Engine Data Base & Kinetic Modeling Parameter Sets

    Energy Technology Data Exchange (ETDEWEB)

    Bunting, Bruce G [ORNL

    2012-10-01

    The automotive and engine industries are in a period of very rapid change being driven by new emission standards, new types of after treatment, new combustion strategies, the introduction of new fuels, and drive for increased fuel economy and efficiency. The rapid pace of these changes has put more pressure on the need for modeling of engine combustion and performance, in order to shorten product design and introduction cycles. New combustion strategies include homogeneous charge compression ignition (HCCI), partial-premixed combustion compression ignition (PCCI), and dilute low temperature combustion which are being developed for lower emissions and improved fuel economy. New fuels include bio-fuels such as ethanol or bio-diesel, drop-in bio-derived fuels and those derived from new crude oil sources such as gas-to-liquids, coal-to-liquids, oil sands, oil shale, and wet natural gas. Kinetic modeling of the combustion process for these new combustion regimes and fuels is necessary in order to allow modeling and performance assessment for engine design purposes. In this research covered by this CRADA, ORNL developed and supplied experimental data related to engine performance with new fuels and new combustion strategies along with interpretation and analysis of such data and consulting to Reaction Design, Inc. (RD). RD performed additional analysis of this data in order to extract important parameters and to confirm engine and kinetic models. The data generated was generally published to make it available to the engine and automotive design communities and also to the Reaction Design Model Fuels Consortium (MFC).

  11. Modeling of Toxicity-Relevant Electrophilic Reactivity for Guanine with Epoxides: Estimating the Hard and Soft Acids and Bases (HSAB) Parameter as a Predictor.

    Science.gov (United States)

    Zhang, Jing; Wang, Chenchen; Ji, Li; Liu, Weiping

    2016-05-16

    According to the electrophilic theory in toxicology, many chemical carcinogens in the environment and/or their active metabolites are electrophiles that exert their effects by forming covalent bonds with nucleophilic DNA centers. The theory of hard and soft acids and bases (HSAB), which states that a toxic electrophile reacts preferentially with a biological macromolecule that has a similar hardness or softness, clarifies the underlying chemistry involved in this critical event. Epoxides are hard electrophiles that are produced endogenously by the enzymatic oxidation of parent chemicals (e.g., alkenes and PAHs). Epoxide ring opening proceeds through a SN2-type mechanism with hard nucleophile DNA sites as the major facilitators of toxic effects. Thus, the quantitative prediction of chemical reactivity would enable a predictive assessment of the molecular potential to exert electrophile-mediated toxicity. In this study, we calculated the activation energies for reactions between epoxides and the guanine N7 site for a diverse set of epoxides, including aliphatic epoxides, substituted styrene oxides, and PAH epoxides, using a state-of-the-art density functional theory (DFT) method. It is worth noting that these activation energies for diverse epoxides can be further predicted by quantum chemically calculated nucleophilic indices from HSAB theory, which is a less computationally demanding method than the exacting procedure for locating the transition state. More importantly, the good qualitative/quantitative correlations between the chemical reactivity of epoxides and their bioactivity suggest that the developed model based on HSAB theory may aid in the predictive hazard evaluation of epoxides, enabling the early identification of mutagenicity/carcinogenicity-relevant SN2 reactivity.

  12. Investigation of the influence of some experimental parameters on the position of the deposition zone in a temperature-gradient tube

    International Nuclear Information System (INIS)

    Helas, G.; Hoffmann, P.; Bachmann, K.

    1978-01-01

    An investigation of the influence of some experimental parameters on thermochromatographic separations has been carried out. It is shown that the position of the deposition zone depends on separation time, purity of the inert gas, and on type and amount of the chlorinating agent. The gas flow rate and the amount of the transported compounds have no influence within the limits of experimental conditions. From the experimental results it can be concluded that in some cases the deposited compounds react with the surface or with the excess gas. (author)

  13. Biomonitoring polycyclic aromatic hydrocarbons by Salix matsudana leaves: A comparison with the relevant air content and evaluation of environmental parameter effects

    Science.gov (United States)

    Zhao, Xiangai; He, Miao; Shang, Haibo; Yu, Hongling; Wang, Hao; Li, Huijie; Piao, Jingyi; Quinto, Maurizio; Li, Donghao

    2018-05-01

    Studies on seasonal distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) in Salix matsudana leaves covering its annual life cycle were carried out in order to evaluate plant leaf response sensitivity to air pollution. Salix matsudana leaves were collected throughout different development phases of plant leaf inclusive of bud break to fallen leaves, covering from spring (May) to autumn (November). Simultaneously, particle and gas samples were collected using a high volume air sampler. Seven different PAHs were determined simultaneously in these samples. The temperature dependence of the partitioning of PAHs in air and plant leaves was investigated and the results were incorporated into a mathematical model. The measured plant/air partition coefficients have been found to be exponentially proportional to the reciprocal temperature, in agreement with theoretical expectations. Furthermore, in order to define the influence of different parameters on PAH adsorption on plant leaves, area and lipid leaf content were also measured. Results demonstrated that temperature plays a very important role in PAHs partitioning and that this value should be carefully considered during sampling, in order to obtain the best correlation between PAHs concentration in air and leaves.

  14. Experimental identification of a comb-shaped chaotic region in multiple parameter spaces simulated by the Hindmarsh—Rose neuron model

    Science.gov (United States)

    Jia, Bing

    2014-03-01

    A comb-shaped chaotic region has been simulated in multiple two-dimensional parameter spaces using the Hindmarsh—Rose (HR) neuron model in many recent studies, which can interpret almost all of the previously simulated bifurcation processes with chaos in neural firing patterns. In the present paper, a comb-shaped chaotic region in a two-dimensional parameter space was reproduced, which presented different processes of period-adding bifurcations with chaos with changing one parameter and fixed the other parameter at different levels. In the biological experiments, different period-adding bifurcation scenarios with chaos by decreasing the extra-cellular calcium concentration were observed from some neural pacemakers at different levels of extra-cellular 4-aminopyridine concentration and from other pacemakers at different levels of extra-cellular caesium concentration. By using the nonlinear time series analysis method, the deterministic dynamics of the experimental chaotic firings were investigated. The period-adding bifurcations with chaos observed in the experiments resembled those simulated in the comb-shaped chaotic region using the HR model. The experimental results show that period-adding bifurcations with chaos are preserved in different two-dimensional parameter spaces, which provides evidence of the existence of the comb-shaped chaotic region and a demonstration of the simulation results in different two-dimensional parameter spaces in the HR neuron model. The results also present relationships between different firing patterns in two-dimensional parameter spaces.

  15. Experimental identification of a comb-shaped chaotic region in multiple parameter spaces simulated by the Hindmarsh—Rose neuron model

    International Nuclear Information System (INIS)

    Jia Bing

    2014-01-01

    A comb-shaped chaotic region has been simulated in multiple two-dimensional parameter spaces using the Hindmarsh—Rose (HR) neuron model in many recent studies, which can interpret almost all of the previously simulated bifurcation processes with chaos in neural firing patterns. In the present paper, a comb-shaped chaotic region in a two-dimensional parameter space was reproduced, which presented different processes of period-adding bifurcations with chaos with changing one parameter and fixed the other parameter at different levels. In the biological experiments, different period-adding bifurcation scenarios with chaos by decreasing the extra-cellular calcium concentration were observed from some neural pacemakers at different levels of extra-cellular 4-aminopyridine concentration and from other pacemakers at different levels of extra-cellular caesium concentration. By using the nonlinear time series analysis method, the deterministic dynamics of the experimental chaotic firings were investigated. The period-adding bifurcations with chaos observed in the experiments resembled those simulated in the comb-shaped chaotic region using the HR model. The experimental results show that period-adding bifurcations with chaos are preserved in different two-dimensional parameter spaces, which provides evidence of the existence of the comb-shaped chaotic region and a demonstration of the simulation results in different two-dimensional parameter spaces in the HR neuron model. The results also present relationships between different firing patterns in two-dimensional parameter spaces

  16. To problem of experimental determination of parameters of μ-atom charge-exchange process of hydrogen isotopes on He nuclei

    International Nuclear Information System (INIS)

    Bystritskij, V.M.; Stolupin, V.A.

    1990-01-01

    The kinetics of μ-atomic and μ-molecular processes occuring in hydrogen isotopes-helium mixture is observed. The expressions are obtained to determine the parameters of a process of the muon transition from hydrogen isotope μ atoms to helium nuclei with the use of different experimental methods. 18 refs.; 3 figs.; 1 tab

  17. Salton and Buckley’s Landmark Research in Experimental Text Information Retrieval. A Review of: Salton, G., & Buckley, C. (1990. Improving retrieval performance by relevance feedback. Journal of the American Society for Information Science, 41(4, 288–297.

    Directory of Open Access Journals (Sweden)

    Christine F. Marton

    2011-01-01

    Full Text Available Objectives – To compare the performance of the vector space model and the probabilistic weighting model of relevance feedback for the overall purpose of determining the most useful relevance feedback procedures. The amount of improvement that can be obtained from searching several test document collections with only one feedback iteration of each relevance feedback model was measured.Design – The experimental design consisted of 72 different tests: 2 different relevance feedback methods, each with 6 permutations, on 6 test document collections of various sizes. A residual collection method was utilized to ascertain the “true advantage provided by the relevance feedback process.” (Salton & Buckley, 1990, p. 293Setting – Department of Computer Science at Cornell University.Subjects – Six test document collections.Methods – Relevance feedback is an effective technique for query modification that provides significant improvement in search performance. Relevance feedback entails both “term reweighting,” the modification of term weights based on term use in retrieved relevant and non-relevant documents, and “query expansion,” which is the addition of new terms from relevant documents retrieved (Harman, 1992. Salton and Buckley (1990 evaluated two established relevance feedback models based on the vector space model (a spatial model and the probabilistic model, respectively. Harman (1992 describes the two key differences between these competing models of relevance feedback.[The vector space model merges] document vectors and original query vectors. This automatically reweights query terms by adding the weights from the actual occurrence of those query terms in the relevant documents, and subtracting the weights of those terms occurring in the non-relevant documents. Queries are automatically expanded by adding all the terms not in the original query that are in the relevant documents and non-relevant documents. They are expanded

  18. Design, calculation and experimental studies for liquid metal system main parameters in support of the liquid lithium fusion reactor

    International Nuclear Information System (INIS)

    Evtikhin, V.A.; Lyublinski, I.E.; Vertkov, A.V.

    2001-01-01

    A new concept of a Liquid Lithium Fusion Reactor and the first experimental results were presented at the 16th IAEA Conference on Fusion Energy. During the past two years theoretical estimations have been made, and calculated and experimental results have been obtained in confirmation of this concept and supporting its progress. The main results of this work are given in the paper. (author)

  19. Design, calculation and experimental studies for liquid metal system main parameters in support of the liquid lithium fusion reactor

    International Nuclear Information System (INIS)

    Evtikhin, V.A.; Lyublinski, I.E.; Vertkov, A.V.

    1999-01-01

    A new concept of a Liquid Lithium Fusion Reactor and the first experimental results were presented at the 16th IAEA Conference on Fusion Energy. During the past two years theoretical estimations have been made, and calculated and experimental results have been obtained in confirmation of this concept and supporting its progress. The main results of this work are given in the paper. (author)

  20. Simple and efficient machine learning frameworks for identifying protein-protein interaction relevant articles and experimental methods used to study the interactions.

    Science.gov (United States)

    Agarwal, Shashank; Liu, Feifan; Yu, Hong

    2011-10-03

    Protein-protein interaction (PPI) is an important biomedical phenomenon. Automatically detecting PPI-relevant articles and identifying methods that are used to study PPI are important text mining tasks. In this study, we have explored domain independent features to develop two open source machine learning frameworks. One performs binary classification to determine whether the given article is PPI relevant or not, named "Simple Classifier", and the other one maps the PPI relevant articles with corresponding interaction method nodes in a standardized PSI-MI (Proteomics Standards Initiative-Molecular Interactions) ontology, named "OntoNorm". We evaluated our system in the context of BioCreative challenge competition using the standardized data set. Our systems are amongst the top systems reported by the organizers, attaining 60.8% F1-score for identifying relevant documents, and 52.3% F1-score for mapping articles to interaction method ontology. Our results show that domain-independent machine learning frameworks can perform competitively well at the tasks of detecting PPI relevant articles and identifying the methods that were used to study the interaction in such articles. Simple Classifier is available at http://sourceforge.net/p/simpleclassify/home/ and OntoNorm at http://sourceforge.net/p/ontonorm/home/.

  1. TSOAK-M1: a computer code to determine tritium reaction/adsorption/release parameters from experimental results of air-detritiation tests

    International Nuclear Information System (INIS)

    Land, R.H.; Maroni, V.A.; Minkoff, M.

    1979-01-01

    A computer code has been developed which permits the determination of tritium reaction (T 2 to HTO)/adsorption/release and instrument correction parameters from enclosure (building) - detritiation test data. The code is based on a simplified model which treats each parameter as a normalized time-independent constant throughout the data-unfolding steps. Because of the complicated four-dimensional mathematical surface generated by the resulting differential equation system, occasional local-minima effects are observed, but these effects can be overcome in most instances by selecting a series of trial guesses for the initial parameter values and observing the reproducibility of final parameter values for cases where the best overall fit to experimental data is achieved. The code was then used to analyze existing small-cubicle test data with good success, and the resulting normalized parameters were employed to evaluate hypothetical reactor-building detritiation scenarios. It was concluded from the latter evaluation that the complications associated with moisture formation, adsorption, and release, particularly in terms of extended cleanup times, may not be as great as was previously thought. It is recommended that the validity of the TSOAK-M1 model be tested using data from detritiation tests conducted on large experimental enclosures (5 to 10 cm 3 ) and, if possible, actual facility buildings

  2. Extrapolated experimental critical parameters of unreflected and steel-reflected massive enriched uranium metal spherical and hemispherical assemblies

    International Nuclear Information System (INIS)

    Rothe, R.E.

    1997-12-01

    Sixty-nine critical configurations of up to 186 kg of uranium are reported from very early experiments (1960s) performed at the Rocky Flats Critical Mass Laboratory near Denver, Colorado. Enriched (93%) uranium metal spherical and hemispherical configurations were studied. All were thick-walled shells except for two solid hemispheres. Experiments were essentially unreflected; or they included central and/or external regions of mild steel. No liquids were involved. Critical parameters are derived from extrapolations beyond subcritical data. Extrapolations, rather than more precise interpolations between slightly supercritical and slightly subcritical configurations, were necessary because experiments involved manually assembled configurations. Many extrapolations were quite long; but the general lack of curvature in the subcritical region lends credibility to their validity. In addition to delayed critical parameters, a procedure is offered which might permit the determination of prompt critical parameters as well for the same cases. This conjectured procedure is not based on any strong physical arguments

  3. Experimental parameters differentially affect the humoral response of the cholera-toxin-based murine model of food allergy

    DEFF Research Database (Denmark)

    Kroghsbo, S.; Christensen, Hanne Risager; Frøkiær, Hanne

    2003-01-01

    Background: Recent studies have developed a murine model of IgE-mediated food allergy based on oral coadministration of antigen and cholera toxin (CT) to establish a maximal response for studying immunopathogenic mechanisms and immunotherapeutic strategies. However, for studying subtle...... interested in characterizing the individual effects of the parameters in the CT-based model: CT dose, antigen type and dose, and number of immunizations. Methods: BALB/c mice were orally sensitized weekly for 3 or 7 weeks with graded doses of CT and various food antigens (soy-trypsin inhibitor, ovalbumin...... of the antibody response depended on the type of antigen and number of immunizations. Conclusions: The critical parameters of the CT-based murine allergy model differentially control the intensity and kinetics of the developing immune response. Adjustment of these parameters could be a key tool for tailoring...

  4. Determination of delta sub(18) in water from delta sub(18) in equilibrated CO2: influence of changes in experimental parameters on the equilibration process

    International Nuclear Information System (INIS)

    Nestler, V.; Arora, H.L.

    1977-01-01

    The result of an isotopic exchange reaction is expressed in terms of the isotopic abundance ratios, the fractionation factor and the atom number ratio of the reactants. The general formula is applied to the CO 2 -H 2 O system and simplified by neglecting terms small in relation to the experimental error. The influence of variations in the experimental parameters on the equilibrium is discussed. It is found that changes in temperature as well as atom number ratio will influence the equilibration process appreciably [pt

  5. Classification of high-resolution multi-swath hyperspectral data using Landsat 8 surface reflectance data as a calibration target and a novel histogram based unsupervised classification technique to determine natural classes from biophysically relevant fit parameters

    Science.gov (United States)

    McCann, C.; Repasky, K. S.; Morin, M.; Lawrence, R. L.; Powell, S. L.

    2016-12-01

    Compact, cost-effective, flight-based hyperspectral imaging systems can provide scientifically relevant data over large areas for a variety of applications such as ecosystem studies, precision agriculture, and land management. To fully realize this capability, unsupervised classification techniques based on radiometrically-calibrated data that cluster based on biophysical similarity rather than simply spectral similarity are needed. An automated technique to produce high-resolution, large-area, radiometrically-calibrated hyperspectral data sets based on the Landsat surface reflectance data product as a calibration target was developed and applied to three subsequent years of data covering approximately 1850 hectares. The radiometrically-calibrated data allows inter-comparison of the temporal series. Advantages of the radiometric calibration technique include the need for minimal site access, no ancillary instrumentation, and automated processing. Fitting the reflectance spectra of each pixel using a set of biophysically relevant basis functions reduces the data from 80 spectral bands to 9 parameters providing noise reduction and data compression. Examination of histograms of these parameters allows for determination of natural splitting into biophysical similar clusters. This method creates clusters that are similar in terms of biophysical parameters, not simply spectral proximity. Furthermore, this method can be applied to other data sets, such as urban scenes, by developing other physically meaningful basis functions. The ability to use hyperspectral imaging for a variety of important applications requires the development of data processing techniques that can be automated. The radiometric-calibration combined with the histogram based unsupervised classification technique presented here provide one potential avenue for managing big-data associated with hyperspectral imaging.

  6. TRIP-ID: A tool for a smart and interactive identification of Magic Formula tyre model parameters from experimental data acquired on track or test rig

    Science.gov (United States)

    Farroni, Flavio; Lamberti, Raffaele; Mancinelli, Nicolò; Timpone, Francesco

    2018-03-01

    Tyres play a key role in ground vehicles' dynamics because they are responsible for traction, braking and cornering. A proper tyre-road interaction model is essential for a useful and reliable vehicle dynamics model. In the last two decades Pacejka's Magic Formula (MF) has become a standard in simulation field. This paper presents a Tool, called TRIP-ID (Tyre Road Interaction Parameters IDentification), developed to characterize and to identify with a high grade of accuracy and reliability MF micro-parameters from experimental data deriving from telemetry or from test rig. The tool guides interactively the user through the identification process on the basis of strong diagnostic considerations about the experimental data made evident by the tool itself. A motorsport application of the tool is shown as a case study.

  7. The quality of reconstructed 3D images in multidetector-row helical CT: experimental study involving scan parameters

    International Nuclear Information System (INIS)

    Shin, Ji Hoon; Lee, Ho Kyu; Choi, Choong Gon; Suh, Dae Chul; Lim, Tae Hwan; Kang, Weechang

    2002-01-01

    To determine which multidetector-row helical CT scanning technique provides the best-quality reconstructed 3D images, and to assess differences in image quality according to the levels of the scanning parameters used. Four objects with different surfaces and contours were scanned using multidetector-row helical CT at three detector-row collimations (1.25, 2.50, 5.00 mm), two pitches (3.0, 6.0), and three different degrees of overlap between the reconstructed slices (0%, 25%, 50%). Reconstructed 3D images of the resulting 72 sets of data were produced using volumetric rendering. The 72 images were graded on a scale from 1 (worst) to 5 (best) for each of four rating criteria, giving a mean score for each criterion and an overall mean score. Statistical analysis was used to assess differences in image quality according to scanning parameter levels. The mean score for each rating criterion, and the overall mean score, varied significantly according to the scanning parameter levels used. With regard to detector-row collimation and pitch, all levels of scanning parameters gave rise to significant differences, while in the degree of overlap of reconstructed slices, there were significant differences between overlap of 0% and of 50% in all levels of scanning parameters, and between overlap of 25% and of 50% in overall accuracy and overall mean score. Among the 18 scanning sequences, the highest score (4.94) was achieved with 1.25 mm detector-row collimation, 3.0 pitch, and 50% overlap between reconstructed slices. Comparison of the quality of reconstructed 3D images obtained using multidetector-row helical CT and various scanning techniques indicated that the 1.25 mm, 3.0, 50% scanning sequence was best. Quality improved as detector-row collimation decreased; as pitch was reduced from 6.0 to 3.0; and as overlap between reconstructed slices increased

  8. Experimental investigation of urea injection parameters influence on NOx emissions from blended biodiesel-fueled diesel engines.

    Science.gov (United States)

    Mehregan, Mina; Moghiman, Mohammad

    2018-02-01

    The present work submits an investigation about the effect of urea injection parameters on NO x emissions from a four-stroke four-cylinder diesel engine fueled with B20 blended biodiesel. An L 9 (3 4 ) Taguchi orthogonal array was used to design the test plan. The results reveal that increasing urea concentration leads to lower NO x emissions. Urea flow rate increment has the same influence on NO x emission. The same result is obtained by an increase in spray angle. Also, according to the analysis of variance (ANOVA), urea concentration and then urea flow rate are the most effective design parameters on NO x emissions, while spray angle and mixing length have less influence on this pollutant emission. Finally, since the result of confirmation test is in good agreement with the predicted value based on the Taguchi technique, the predictive capability of this method in the present study could be deduced.

  9. Experimental investigations on the effect of process parameters with the use of minimum quantity solid lubrication in turning

    Science.gov (United States)

    Makhesana, Mayur A.; Patel, K. M.; Mawandiya, B. K.

    2018-04-01

    Turning process is a very basic process in any field of mechanical application. During turning process, most of the energy is converted into heat because of the friction between work piece and tool. Heat generation can affect the surface quality of the work piece and tool life. To reduce the heat generation, Conventional Lubrication process is used in most of the industry. Minimum quantity lubrication has been an effective alternative to improve the performance of machining process. In this present work, effort has been made to study the effect of various process parameters on the surface roughness and power consumption during turning of EN8 steel material. Result revealed the effect of depth of cut and feed on the obtained surface roughness value. Further the effect of solid lubricant has been also studied and optimization of process parameters is also done for the turning process.

  10. An experimental study of dependence of hydro turbine vibration parameters on pressure pulsations in the flow path

    Science.gov (United States)

    Dekterev, D.; Maslennikova, A.; Abramov, A.

    2017-09-01

    The operation modes of the hydraulic power plant water turbine with the formation of a precessing vortex core were studied on the hydrodynamic set-up with the model of hydraulic unit. The dependence of low-frequency vibrations on flow pressure pulsations in the hydraulic unit was established. The results of the air injection effect on the vibrational parameters of the hydrodynamic set-up were presented.

  11. EXPERIMENTAL INVESTIGATION OF EMISSION AND PERFORMANCE PARAMETERS OF PONGAMIA BIODIESEL AND HHO GAS ADDITION IN A COMPRESSION IGNITION ENGINE

    OpenAIRE

    Allen Jeffrey.J1, Divya Meena.S2, Balaji.P3, Bharathi.K4, Arvind Raj.R5

    2018-01-01

    Nowadays the environmental pollution has been increased incredibly by using conventional fuels. To control this increase in pollution alternate fuels has to be used as supplement for conventional fuels. While using conventional fuels such as petrol and diesel in IC engine there is a chance of increase in emissions. Alternate fuels can control emissions. This work is based on the investigation of emission parameters of pongamia biodiesel and HHO gas addition in a CI engine. Pongamia biodiesel ...

  12. Electron microscopy of human peripheral nerves of clinical relevance to the practice of nerve blocks. A structural and ultrastructural review based on original experimental and laboratory data.

    Science.gov (United States)

    Reina, M A; Arriazu, R; Collier, C B; Sala-Blanch, X; Izquierdo, L; de Andrés, J

    2013-12-01

    The goal is to describe the ultrastructure of normal human peripheral nerves, and to highlight key aspects that are relevant to the practice of peripheral nerve block anaesthesia. Using samples of sciatic nerve obtained from patients, and dural sac, nerve root cuff and brachial plexus dissected from fresh human cadavers, an analysis of the structure of peripheral nerve axons and distribution of fascicles and topographic composition of the layers that cover the nerve is presented. Myelinated and unmyelinated axons, fascicles, epineurium, perineurium and endoneurium obtained from patients and fresh cadavers were studied by light microscopy using immunohistochemical techniques, and transmission and scanning electron microscopy. Structure of perineurium and intrafascicular capillaries, and its implications in blood-nerve barrier were revised. Each of the anatomical elements is analyzed individually with regard to its relevance to clinical practice to regional anaesthesia. Routine practice of regional anaesthetic techniques and ultrasound identification of nerve structures has led to conceptions, which repercussions may be relevant in future applications of these techniques. In this regard, the ultrastructural and histological perspective accomplished through findings of this study aims at enlightening arising questions within the field of regional anaesthesia. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  13. Experimental impact-parameter--dependent probabilities for K-shell vacancy production by fast heavy-ion projectiles

    International Nuclear Information System (INIS)

    Randall, R.R.; Bednar, J.A.; Curnutte, B.; Cocke, C.L.

    1976-01-01

    The impact-parameter dependence of the probability for production of target K x rays has been measured for oxygen projectiles on copper and for carbon and fluorine projectiles on argon at scaled velocities near 0.5. The O-on-Cu data were taken for 1.56-, 1.88-, and 2.69-MeV/amu O beams incident upon thin Cu foils. A thin Ar-gas target was used for 1.56-MeV/amu C and F beams, permitting measurements to be made for charge-pure C +4 , C +6 , F +9 and F +5 projectiles. Ar and Cu K x rays were observed with a Si(Li) detector and scattered projectiles with a collimated surface-barrier detector. Comparison of the shapes of the measured K-vacancy--production probability curves with predictions of the semiclassical Coulomb approximation (SCA) shows adequate agreement for the O-on-Cu system. For the higher ratio of projectile-to-target nuclear charge (Z 1 /Z 2 ) characterizing the C-on-Ar and F-on-Ar systems, the SCA predictions are entirely inadequate in describing the observed impact-parameter dependence. In particular, they cannot account for large probabilities found at large impact parameters. Furthermore, the dependence of the shapes on the projectile charge state is found to become pronounced at larger Z 1 /Z 2 . Attempts to account for this behavior in terms of alternative vacancy-production processes are discussed

  14. Adaptive Neuro-Fuzzy Determination of the Effect of Experimental Parameters on Vehicle Agent Speed Relative to Vehicle Intruder.

    Science.gov (United States)

    Shamshirband, Shahaboddin; Banjanovic-Mehmedovic, Lejla; Bosankic, Ivan; Kasapovic, Suad; Abdul Wahab, Ainuddin Wahid Bin

    2016-01-01

    Intelligent Transportation Systems rely on understanding, predicting and affecting the interactions between vehicles. The goal of this paper is to choose a small subset from the larger set so that the resulting regression model is simple, yet have good predictive ability for Vehicle agent speed relative to Vehicle intruder. The method of ANFIS (adaptive neuro fuzzy inference system) was applied to the data resulting from these measurements. The ANFIS process for variable selection was implemented in order to detect the predominant variables affecting the prediction of agent speed relative to intruder. This process includes several ways to discover a subset of the total set of recorded parameters, showing good predictive capability. The ANFIS network was used to perform a variable search. Then, it was used to determine how 9 parameters (Intruder Front sensors active (boolean), Intruder Rear sensors active (boolean), Agent Front sensors active (boolean), Agent Rear sensors active (boolean), RSSI signal intensity/strength (integer), Elapsed time (in seconds), Distance between Agent and Intruder (m), Angle of Agent relative to Intruder (angle between vehicles °), Altitude difference between Agent and Intruder (m)) influence prediction of agent speed relative to intruder. The results indicated that distance between Vehicle agent and Vehicle intruder (m) and angle of Vehicle agent relative to Vehicle Intruder (angle between vehicles °) is the most influential parameters to Vehicle agent speed relative to Vehicle intruder.

  15. A Comparative Experimental Study on the Use of Machine Learning Approaches for Automated Valve Monitoring Based on Acoustic Emission Parameters

    Science.gov (United States)

    Ali, Salah M.; Hui, K. H.; Hee, L. M.; Salman Leong, M.; Al-Obaidi, M. A.; Ali, Y. H.; Abdelrhman, Ahmed M.

    2018-03-01

    Acoustic emission (AE) analysis has become a vital tool for initiating the maintenance tasks in many industries. However, the analysis process and interpretation has been found to be highly dependent on the experts. Therefore, an automated monitoring method would be required to reduce the cost and time consumed in the interpretation of AE signal. This paper investigates the application of two of the most common machine learning approaches namely artificial neural network (ANN) and support vector machine (SVM) to automate the diagnosis of valve faults in reciprocating compressor based on AE signal parameters. Since the accuracy is an essential factor in any automated diagnostic system, this paper also provides a comparative study based on predictive performance of ANN and SVM. AE parameters data was acquired from single stage reciprocating air compressor with different operational and valve conditions. ANN and SVM diagnosis models were subsequently devised by combining AE parameters of different conditions. Results demonstrate that ANN and SVM models have the same results in term of prediction accuracy. However, SVM model is recommended to automate diagnose the valve condition in due to the ability of handling a high number of input features with low sampling data sets.

  16. Adaptive Neuro-Fuzzy Determination of the Effect of Experimental Parameters on Vehicle Agent Speed Relative to Vehicle Intruder.

    Directory of Open Access Journals (Sweden)

    Shahaboddin Shamshirband

    Full Text Available Intelligent Transportation Systems rely on understanding, predicting and affecting the interactions between vehicles. The goal of this paper is to choose a small subset from the larger set so that the resulting regression model is simple, yet have good predictive ability for Vehicle agent speed relative to Vehicle intruder. The method of ANFIS (adaptive neuro fuzzy inference system was applied to the data resulting from these measurements. The ANFIS process for variable selection was implemented in order to detect the predominant variables affecting the prediction of agent speed relative to intruder. This process includes several ways to discover a subset of the total set of recorded parameters, showing good predictive capability. The ANFIS network was used to perform a variable search. Then, it was used to determine how 9 parameters (Intruder Front sensors active (boolean, Intruder Rear sensors active (boolean, Agent Front sensors active (boolean, Agent Rear sensors active (boolean, RSSI signal intensity/strength (integer, Elapsed time (in seconds, Distance between Agent and Intruder (m, Angle of Agent relative to Intruder (angle between vehicles °, Altitude difference between Agent and Intruder (m influence prediction of agent speed relative to intruder. The results indicated that distance between Vehicle agent and Vehicle intruder (m and angle of Vehicle agent relative to Vehicle Intruder (angle between vehicles ° is the most influential parameters to Vehicle agent speed relative to Vehicle intruder.

  17. Development and Experimental Validation of Large Eddy Simulation Techniques for the Prediction of Combustion-Dynamic Process in Syngas Combustion: Characterization of Autoignition, Flashback, and Flame-Liftoff at Gas-Turbine Relevant Operating Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ihme, Matthias [Univ. of Michigan, Ann Arbor, MI (United States); Driscoll, James [Univ. of Michigan, Ann Arbor, MI (United States)

    2015-08-31

    The objective of this closely coordinated experimental and computational research effort is the development of simulation techniques for the prediction of combustion processes, relevant to the oxidation of syngas and high hydrogen content (HHC) fuels at gas-turbine relevant operating conditions. Specifically, the research goals are (i) the characterization of the sensitivity of syngas ignition processes to hydrodynamic processes and perturbations in temperature and mixture composition in rapid compression machines and ow-reactors and (ii) to conduct comprehensive experimental investigations in a swirl-stabilized gas turbine (GT) combustor under realistic high-pressure operating conditions in order (iii) to obtain fundamental understanding about mechanisms controlling unstable flame regimes in HHC-combustion.

  18. Experimental study on Response Parameters of Ni-rich NiTi Shape Memory Alloy during Wire Electric Discharge Machining

    Science.gov (United States)

    Bisaria, Himanshu; Shandilya, Pragya

    2018-03-01

    Nowadays NiTi SMAs are gaining more prominence due to their unique properties such as superelasticity, shape memory effect, high fatigue strength and many other enriched physical and mechanical properties. The current studies explore the effect of machining parameters namely, peak current (Ip), pulse off time (TOFF), and pulse on time (TON) on wire wear ratio (WWR), and dimensional deviation (DD) in WEDM. It was found that high discharge energy was mainly ascribed to high WWR and DD. The WWR and DD increased with the increase in pulse on time and peak current whereas high pulse off time was favourable for low WWR and DD.

  19. ESTIMATION OF HYDRAULIC CONDUCTIVITY AND CONTENT OF FINES FROM EXPERIMENTAL LAWS THAT CORELATE HYDRAULIC AND ELECTRIC PARAMETERS

    Directory of Open Access Journals (Sweden)

    Héctor José Peinado-Guevara

    2010-09-01

    Full Text Available Hydraulic conductivity is a basic element in the advancement of knowledge of a geological environment in both the flow and transport processes of pollutants for conservation projects, managementand environmental management and also for the development of public policies for protection of ecosystems, among others. The aim of this paper is to obtain the hydraulic conductivity (K and the finescontent (C of saturated granular half using two empirical laws. One correlates the electrical conductivity of saturated granular media σo and water saturated σw which depends on the formation factor(F, cation exchange capacity (CEC and the fines content in the saturated soil. Using data obtained from materials of 18 samples from 6 wells the relationships between F-C and CEC-C were obtained,so the equation reduces to a σo function in terms of σw and C, with a correlation coefficient of R = 0.97. A second experimental law is the one that results from the experimental relationship between K and C,being 1.4054 K 0.1804.C with a correlation coefficient of R = 0.96. From both experimental expressions relationships between K and C, a and C,and C are created so from every pair knowing one of them you get to know the other one. Under the scheme outlined electrical conductivity sections for the saturated medium and fines content are obtained,finding that the groundwater in the study area consists of a thin top layer and beneath it there is a predominantly sandy environment.

  20. Effect of Fluid Bypassing on the Experimentally Obtained Darcy and Non-Darcy Permeability Parameters of Ceramic Foam Filters

    Science.gov (United States)

    Akbarnejad, Shahin; Saffari Pour, Mohsen; Jonsson, Lage Tord Ingemar; Jönsson, Pӓr Göran

    2017-02-01

    Ceramic foam filters (CFFs) are used to remove solid particles and inclusions from molten metal. In general, molten metal which is poured on the top of a CFF needs to reach a certain height to build the required pressure (metal head) to prime the filter. To estimate the required metal head, it is necessary to obtain permeability coefficients using permeametry experiments. It has been mentioned in the literature that to avoid fluid bypassing, during permeametry, samples need to be sealed. However, the effect of fluid bypassing on the experimentally obtained pressure gradients seems not to be explored. Therefore, in this research, the focus was on studying the effect of fluid bypassing on the experimentally obtained pressure gradients as well as the empirically obtained Darcy and non-Darcy permeability coefficients. Specifically, the aim of the research was to investigate the effect of fluid bypassing on the liquid permeability of 30, 50, and 80 pores per inch (PPI) commercial alumina CFFs. In addition, the experimental data were compared to the numerically modeled findings. Both studies showed that no sealing results in extremely poor estimates of the pressure gradients and Darcy and non-Darcy permeability coefficients for all studied filters. The average deviations between the pressure gradients of the sealed and unsealed 30, 50, and 80 PPI samples were calculated to be 57.2, 56.8, and 61.3 pct. The deviations between the Darcy coefficients of the sealed and unsealed 30, 50, and 80 PPI samples found to be 9, 20, and 31 pct. The deviations between the non-Darcy coefficients of the sealed and unsealed 30, 50, and 80 PPI samples were calculated to be 59, 58, and 63 pct.

  1. DFT and experimental studies on structure and spectroscopic parameters of 3,6-diiodo-9-ethyl-9H-carbazole

    DEFF Research Database (Denmark)

    Radula-Janik, Klaudia; Kupka, Teobald; Ejsmont, Krzysztof

    2016-01-01

    The first report on crystal and molecular structure of 3,6-diiodo-9-ethyl-9H-carbazole is presented. Experimental room-temperature X-ray and 13C chemical shift studies were supported by advanced theoretical calculations using density functional theory (DFT). The 13C nuclear magnetic shieldings were...... predicted at the non-relativistic and relativistic level of theory using the zeroth-order regular approximation (ZORA). Theoretical relativistic calculations of chemical shifts of carbons C3 and C6, directly bonded to iodine atoms, produced a reasonable agreement with experiment (initial deviation from...

  2. PVTxy properties of CO2 mixtures relevant for CO2 capture, transport and storage: Review of available experimental data and theoretical models

    International Nuclear Information System (INIS)

    Li, Hailong; Jakobsen, Jana P.; Wilhelmsen, Oivind; Yan, Jinyue

    2011-01-01

    Highlights: → Accurate knowledge about the thermodynamic properties of CO 2 is essential in the design and operation of CCS systems. → Experimental data about the phase equilibrium and density of CO 2 -mixtures have been reviewed. → Equations of state have been reviewed too regarding CO 2 -mixtures. None has shown any clear advantage in CCS applications. → Identified knowledge gaps suggest to conducting more experiments and developing novel models. -- Abstract: The knowledge about pressure-volume-temperature-composition (PVTxy) properties plays an important role in the design and operation of many processes involved in CO 2 capture and storage (CCS) systems. A literature survey was conducted on both the available experimental data and the theoretical models associated with the thermodynamic properties of CO 2 mixtures within the operation window of CCS. Some gaps were identified between available experimental data and requirements of the system design and operation. The major concerns are: for the vapour-liquid equilibrium, there are no data about CO 2 /COS and few data about the CO 2 /N 2 O 4 mixture. For the volume property, there are no published experimental data for CO 2 /O 2 , CO 2 /CO, CO 2 /N 2 O 4 , CO 2 /COS and CO 2 /NH 3 and the liquid volume of CO 2 /H 2 . The experimental data available for multi-component CO 2 mixtures are also scarce. Many equations of state are available for thermodynamic calculations of CO 2 mixtures. The cubic equations of state have the simplest structure and are capable of giving reasonable results for the PVTxy properties. More complex equations of state such as Lee-Kesler, SAFT and GERG typically give better results for the volume property, but not necessarily for the vapour-liquid equilibrium. None of the equations of state evaluated in the literature show any clear advantage in CCS applications for the calculation of all PVTxy properties. A reference equation of state for CCS should, thus, be a future goal.

  3. Prediction of the time course of callus stiffness as a function of mechanical parameters in experimental rat fracture healing studies--a numerical study.

    Directory of Open Access Journals (Sweden)

    Tim Wehner

    Full Text Available Numerous experimental fracture healing studies are performed on rats, in which different experimental, mechanical parameters are applied, thereby prohibiting direct comparison between each other. Numerical fracture healing simulation models are able to predict courses of fracture healing and offer support for pre-planning animal experiments and for post-hoc comparison between outcomes of different in vivo studies. The aims of this study are to adapt a pre-existing fracture healing simulation algorithm for sheep and humans to the rat, to corroborate it using the data of numerous different rat experiments, and to provide healing predictions for future rat experiments. First, material properties of different tissue types involved were adjusted by comparing experimentally measured callus stiffness to respective simulated values obtained in three finite element (FE models. This yielded values for Young's moduli of cortical bone, woven bone, cartilage, and connective tissue of 15,750 MPa, 1,000 MPa, 5 MPa, and 1 MPa, respectively. Next, thresholds in the underlying mechanoregulatory tissue differentiation rules were calibrated by modifying model parameters so that predicted fracture callus stiffness matched experimental data from a study that used rigid and flexible fixators. This resulted in strain thresholds at higher magnitudes than in models for sheep and humans. The resulting numerical model was then used to simulate numerous fracture healing scenarios from literature, showing a considerable mismatch in only 6 of 21 cases. Based on this corroborated model, a fit curve function was derived which predicts the increase of callus stiffness dependent on bodyweight, fixation stiffness, and fracture gap size. By mathematically predicting the time course of the healing process prior to the animal studies, the data presented in this work provides support for planning new fracture healing experiments in rats. Furthermore, it allows one to transfer and

  4. Stability assessment and operating parameter optimization on experimental results in very small plasma focus, using sensitivity analysis

    Science.gov (United States)

    Jafari, Hossein; Habibi, Morteza

    2018-04-01

    Regarding the importance of stability in small-scale plasma focus devices for producing the repeatable and strength pinching, a sensitivity analysis approach has been used for applicability in design parameters optimization of an actually very low energy device (84 nF, 48 nH, 8-9.5 kV, ∼2.7-3.7 J). To optimize the devices functional specification, four different coaxial electrode configurations have been studied, scanning an argon gas pressure range from 0.6 to 1.5 mbar via the charging voltage variation study from 8.3 to 9.3 kV. The strength and efficient pinching was observed for the tapered anode configuration, over an expanded operating pressure range of 0.6 to 1.5 mbar. The analysis results showed that the most sensitive of the pinch voltage was associated with 0.88 ± 0.8mbar argon gas pressure and 8.3-8.5 kV charging voltage, respectively, as the optimum operating parameters. From the viewpoint of stability assessment of the device, it was observed that the least variation in stable operation of the device was for a charging voltage range of 8.3 to 8.7 kV in an operating pressure range from 0.6 to 1.1 mbar.

  5. Experimental study on effect of hydroalcoholic extract of Emblica officinalis fruits on glucose homeostasis and metabolic parameters

    Science.gov (United States)

    Patel, Snehal S.; Goyal, Ramesh K.; Shah, Rajendra S.; Tirgar, Pravin R.; Jadav, Pinakin D.

    2013-01-01

    Polyphenols from natural source are potential therapeutics that act alone or supplement anti-diabetic drugs in the prevention and treatment of diabetes. The present investigation was undertaken to study the effect of hydroalcoholic extract (HE) of fruits of Emblica officinalis on type 1 diabetic rats. Diabetes was induced by streptozotocin (STZ) (45 mg/kg i.v.). HE (100 mg/kg, p.o.) was administered for 4 weeks and at the end of treatment, blood samples were collected and analyzed for various biochemical parameters. STZ produced a diabetic state exhibiting all the cardinal symptoms such as loss of body weight, polydipsia, polyuria, glucosuria, polyphagia, hypoinsulinemia, and hyperglycemia associated with hypercholesterolemia and hypertriglyceridemia. Treatment with HE prevented cardinal symptoms and caused significant decrease in fasting serum glucose, AUCglucose, cholesterol, triglyceride, low-density lipoprotein (LDL) and very LDL in diabetic rats. However, insulin, AUCinsulin, and serum high-density lipoprotein level were not significantly altered by treatment. Treatment also reduced lipid peroxidation and increased anti-oxidant parameters in the liver homogenates of diabetic rats. Polyphenol enriched fraction of HE significantly improved disarranged carbohydrate and lipid metabolism of chemically induced diabetes in rats. The mechanism of its anti-diabetic activity appears to be either improvement in peripheral glucose utilization, increased insulin sensitivity, or anti-oxidant property. PMID:24696584

  6. Effect Analysis of Geometric Parameters on Stainless Steel Stamping Multistage Pump by Experimental Test and Numerical Calculation

    Directory of Open Access Journals (Sweden)

    Chuan Wang

    2013-01-01

    Full Text Available In order to improve the efficiency of stainless steel stamping multistage pump, quadratic regression orthogonal test, hydraulic design, and computational fluid dynamics (CFD are used to analyze the effect of pump geometric parameters. Sixteen impellers are designed based on the quadratic regression orthogonal test, which have three factors including impeller outlet slope, impeller blade outlet stagger angle, and impeller blade outlet width. Through quadratic regression equation, the function relationship between efficiency values and three factors is established. The optimal combination of geometric parameters is found through the analysis of the regression equation. To further study the influence of blade thickness on the performance of multistage pump, numerical simulations of multistage pump with different blade thicknesses are carried out. The influence law of blade thickness on pump performance is built from the external characteristics and internal flow field. In conclusion, with the increase of blade thickness, the best efficiency point of the pump shifts to the small flow rate direction, and the vortex regions inside the pump at rated flow gradually increase, which is the main reason that pump efficiency decreases along with the increase of the blade thickness at rated flow.

  7. MR imaging of experimental subdural bleeding. Correlates of brain deformation and tissue water content, and changes in vital physiological parameters

    International Nuclear Information System (INIS)

    Orlin, J.R.; Thuomas, K.Aa.; Ponten, U.; Bergstroem, K.; Zwetnow, N.N.

    1997-01-01

    Purpose: To evaluate morphological and physiological changes during acute lethal subdural bleeding in 2 models of anaesthetized dogs. Material and Methods: In model I, blood from the aorta was led into a collapsed subdural rubber balloon while in model II, the blood was directed into the subdural compartment over the left cerebral frontoparietal lobe. Eight vital physiological parameters were continuously registered. MR imaging visualized the compression and displacement of cerebral tissue, and assessed the dynamic changes in cerebral tissue water. Results: In model I, tissue herniation and compression of cerebral ventricles led to death at a haematoma volume corresponding to 8% of the intracranial volume. In model II, the extravasated blood progressed infratentorially and into the spinal sac with a volume that was 3 times larger than that of the lethal haematoma. Tissue water increased almost linearly during bleeding in both models. (orig.)

  8. Experimental Study of Three-body Cabibbo-suppressed D0 Decays and Extraction of Cp Violation Parameters

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Kalanand; /Nehru U.

    2008-02-22

    The authors present measurements of the relative branching ratios, Dalitz plot structures and CP-asymmetry values in the three-body singly Cabibbo-suppressed decays D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup 0} and D{sup 0} {yields} K{sup -}K{sup +}{pi}{sup 0} using data collected by the BABAR detector at the PEP-II asymmetric-energy ring at SLAC. The author applies the results of the D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup 0} analysis to extracting CP-violation parameters related to the CKM angle {gamma} (or {phi}{sub 3}) using the decay B{sup -} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} K{sup -}.

  9. A preliminary definition of the parameters of an experimental natural - uranium, graphite - moderated, helium - cooled power reactor

    International Nuclear Information System (INIS)

    Baltazar, O.

    1978-01-01

    A preliminary study of the technical characteristic of an experiment at 32 MWe power with a natural uconium, graphite-moderated, helium cooled reactor is described. The national participation and the use of reactor as an instrument for the technological development of future high temperature gas cooled reactor is considered in the choice of the reactor type. Considerations about nuclear power plants components based in extensive bibliography about similar english GCR reactor is presented. The main thermal, neutronic an static characteristic and in core management of the nuclear fuel is stablished. A simplified scheme of the secondary system and its thermodynamic performance is determined. A scheme of parameters calculation of the reactor type is defined based in the present capacity of calculation developed by Coordenadoria de Engenharia Nuclear and Centro de Processamento de Dados, IEA, Brazil [pt

  10. Operating experience of the TPA-1001 mini-computer in experimental control systems of main synchrophasotron parameters

    International Nuclear Information System (INIS)

    Kazanskij, G.S.; Khoshenko, A.A.

    1978-01-01

    The experience of application of a Mini-computer, TPA-1001 to control the basic parameters of a synchrophasotron is discussed. The available data have shown that the efficiency of a computer management and measurement system (CMMS) for an accelerator can be determined as a trade-off between the accelerator and the system reliability, and betWeen the system mobility and its softWare. At present, the system employs two VT-340 display units, an arithmetic unit and an accelerating frequency measurement loop. In addition, the system memory is expanded up to 12 K. A new interactive program has been developed which enables the user to interact with the system Via three units (a teletype and two display units). An accelerating frequency measuring and control flowchart has been implemented and covers the whole duty cycle, while its measuring accuracy is better than 4x10 -4

  11. Towards optimization of experimental parameters for studying Li-O2 battery discharge products in TEM using in situ EELS.

    Science.gov (United States)

    Basak, Shibabrata; Jansen, Jacob; Kabiri, Yoones; Zandbergen, Henny W

    2018-05-01

    The key to understanding the performance of Li-O 2 batteries is to study the chemical and structural properties of their discharge product(s) at the nanometer scale. Using TEM for this purpose poses challenges due to the sensitivity of samples to air and electron beams. This paper describes our use of in situ EELS to evaluate experimental procedures to reduce electron-beam degradation and presents methods to deal with air sensitivity. Our results show that Li 2 O 2 decomposition is dependent on the total dose and is approximately 4-5 times more pronounced at 80 than at 200 kV. We also demonstrate the benefits of using low-dose-rate STEM. We show further that a "graphene cell", which encapsulates the sample within graphene sheets, can protect the sample against air and e-beam damage. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Hydrocarbon deposition in gaps of tungsten and graphite tiles in Experimental Advanced Superconducting Tokamak edge plasma parameters

    International Nuclear Information System (INIS)

    Xu Qian; Yang Zhongshi; Luo Guangnan

    2015-01-01

    The three-dimensional (3D) Monte Carlo code PIC-EDDY has been utilized to investigate the mechanism of hydrocarbon deposition in gaps of tungsten tiles in the Experimental Advanced Superconducting Tokamak (EAST), where the sheath potential is calculated by the 2D in space and 3D in velocity particle-in-cell method. The calculated results for graphite tiles using the same method are also presented for comparison. Calculation results show that the amount of carbon deposited in the gaps of carbon tiles is three times larger than that in the gaps of tungsten tiles when the carbon particles from re-erosion on the top surface of monoblocks are taken into account. However, the deposition amount is found to be larger in the gaps of tungsten tiles at the same CH 4 flux. When chemical sputtering becomes significant as carbon coverage on tungsten increases with exposure time, the deposition inside the gaps of tungsten tiles would be considerable. (author)

  13. Non-spatial pre-training in the water maze as a clinically relevant model for evaluating learning and memory in experimental TBI.

    Science.gov (United States)

    Wagner, Amy K; Brayer, Samuel W; Hurwitz, Max; Niyonkuru, Christian; Zou, Huichao; Failla, Michelle; Arenth, Patricia; Manole, Mioara D; Skidmore, Elizabeth; Thiels, Edda

    2013-11-01

    Explicit and implicit learning and memory networks exist where each network can facilitate or inhibit cognition. Clinical evidence suggests that implicit networks are relatively preserved after traumatic brain injury (TBI). Non-spatial pre-training (NSPT) in the Morris Water Maze (MWM) provides the necessary behavioral components to complete the task, while limiting the formation of spatial maps. Our study utilized NSPT in the MWM to assess implicit and explicit learning and memory system deficits in the controlled cortical impact (CCI) model of TBI. 76 adult male Sprague-Dawley rats were divided: CCI vs. sham surgery, NSPT vs. No-NSPT, and cued vs. non-cued groups. NSPT occurred for 4d prior to surgery (dynamic hidden platform location, extra-maze cues covered, static pool entry point). Acquisition (d14-18), Probe/Visible Platform (d19), and Reversal (d20-21) trials were conducted with or without extra-maze cues. Novel time allocation and search strategy selection metrics were utilized. Results indicated implicit and explicit learning/memory networks are distinguishable in the MWM. In the cued condition, NSPT reduced thigmotaxis, improved place learning, and largely eliminated the apparent injury-induced deficits typically observed between untrained CCI and sham rats. However, among NSPT groups, incorporation of cues into search strategy selection for CCI rats was relatively impaired compared to shams. Non-cued condition performance showed sham/NSPT and CCI/NSPT rats perform similarly, suggesting implicit memory networks are largely intact 2weeks after CCI. Place learning differences between CCI/NSPT and sham/NSPT rats more accurately reflect spatial deficits in our CCI model compared to untrained controls. These data suggest NSPT as a clinically relevant construct for evaluating potential neurorestorative and neuroprotective therapies. These findings also support development of non-spatial cognitive training paradigms for evaluating rehabilitation relevant

  14. Experimental methods for screening parameters influencing the growth to product yield (Y(x/CH4 of a biological methane production (BMP process performed with Methanothermobacter marburgensis

    Directory of Open Access Journals (Sweden)

    Sébastien Bernacchi

    2014-12-01

    Full Text Available 1. Specht M, Brellochs J, Frick V, et al. (2010 Storage of renewable energy in the natural gas grid. Erdoel, Erdgas, Kohle 126: 342-345.2. Thauer RK, Kaster AK, Goenrich M, et al. (2010 Hydrogenases from methanogenic archaea, nickel, a novel cofactor, and H2 storage. Annu Rev Biochem 79: 507-536.3. Liu Y, Whitman WB (2008 Metabolic, phylogenetic, and ecological diversity of the methanogenic archaea. Ann N Y Acad Sci 1125: 171-189.4. Kaster AK, Goenrich M, Seedorf H, et al. (2011 More than 200 genes required for methane formation from H2 and CO2 and energy conservation are present in Methanothermobacter marburgensis and Methanothermobacter thermautotrophicus. Archaea ID 973848: 1-23.5. Seifert AH, Rittmann S, Herwig C (2014 Analysis of process related factors to increase volumetric productivity and quality of biomethane with Methanothermobacter marburgensis Appl Energ 132: 155-162.6. Bernacchi S, Weissgram M, Wukovits W, et al. (2014 Process efficiency simulation for key process parameters in biological methanogenesis. AIMS bioengineering 1: 53-71.7. Thauer RK, Kaster AK, Seedorf H, et al. (2008 Methanogenic archaea: ecologically relevant differences in energy conservation. Nat Rev Microbiol 6: 579-591.8. Schill N, van Gulik WM, Voisard D, et al. (1996 Continuous cultures limited by a gaseous substrate: development of a simple, unstructure mathematical model and experimental verification with Methanobacterium thermoautotrophicum. Biotechnol Bioeng 51: 645-658.9. Jud G, Schneider K, Bachofen R (1997 The role of hydrogen mass transfer for the growth kinetics of Methanobacterium thermoautotrophicum in batch and chemostat cultures. J Ind Microbiol Biotechnol 19: 246-251.10. Tsao JH, Kaneshiro SM, Yu SS, et al. (1994 Continuous culture of Methanococcus jannaschii, an extremely thermophilic methanogen. Biotechnol Bioeng 43: 258-261.11. Schill N, van Gulik WM, Voisard D, et al. (1996 Continuous cultures limited by a gaseous substrate: development of a

  15. Towards a generic procedure for the detection of relevant contaminants from waste electric and electronic equipment (WEEE) in plastic food-contact materials: a review and selection of key parameters.

    Science.gov (United States)

    Puype, Franky; Samsonek, Jiří; Vilímková, Věra; Kopečková, Šárka; Ratiborská, Andrea; Knoop, Jan; Egelkraut-Holtus, Marion; Ortlieb, Markus; Oppermann, Uwe

    2017-10-01

    Recently, traces of brominated flame retardants (BFRs) have been detected in black plastic food-contact materials (FCMs), indicating the presence of recycled plastics, mainly coming from waste electric and electronic equipment (WEEE) as BFRs are one of the main additives in electric applications. In order to evaluate efficiently and preliminary in situ the presence of WEEE in plastic FCMs, a generic procedure for the evaluation of WEEE presence in plastic FCMs by using defined parameters having each an associated importance level has been proposed. This can be achieved by combining parameters like overall bromine (Br) and antimony (Sb) content; additive and reactive BFR, rare earth element (REE) and WEEE-relevant elemental content and additionally polymer purity. In most of the cases, the WEEE contamination could be confirmed by combining X-ray fluorescence (XRF) spectrometry and thermal desorption/pyrolysis gas chromatography-mass spectrometry (GC-MS) at first. The Sb and REE content did not give a full confirmation as to the source of contamination, however for Sb the opposite counts: Sb was joined with elevated Br signals. Therefore, Br at first followed by Sb were used as WEEE precursors as both elements are used as synergetic flame-retardant systems. WEEE-specific REEs could be used for small WEEE (sWEEE) confirmation; however, this parameter should be interpreted with care. The polymer purity by Fourier-transform infrared spectrometer (FTIR) and pyrolysis GC-MS in many cases could not confirm WEEE-specific contamination; however, it can be used for purity measurements and for the suspicion of the usage of recycled fractions (WEEE and non-WEEE) as a third-line confirmation. To the best of our knowledge, the addition of WEEE waste to plastic FCMs is illegal; however, due to lack on screening mechanisms, there is still the breakthrough of such articles onto the market, and, therefore, our generic procedure enables the quick and effective screening of suspicious

  16. Experimental researches and comparison on aerodynamic parameters and cleaning efficiency of multi-level multi-channel cyclone

    Directory of Open Access Journals (Sweden)

    Aleksandras Chlebnikovas

    2015-10-01

    Full Text Available Multi-level multi-channel cyclone – the lately designed air cleaning device that can remove ultra-fine 20 μm particulatematter (PM from dusted air and reach over 95% of the overall cleaning efficiency. Multi-channel cyclone technology is based on centrifugal forces and has the resulting additional filtering process operation. Multi-level structure of cyclone allows to achieve higher air flow cleaning capacity at the same dimensions of the device, thus saving installation space required for the job, production and operating costs. Studies have examined the air flow parameters change in one–, two– and three–levels multichannel cyclone. These constructions differ according to the productivity of cleaned air under the constant peripheral and transitional (50/50 case air flow relations. Accordance with the results of air flow dynamics – velocity distribution of multi-channel cyclone, aerodynamic resistance and efficiency can be judged on the flow turbulence, the flow channel cross-section and select the most appropriate application. Cleaning efficiency studies were carried out using fine granite and wood ashes PM. The maximum cleaning efficiency was 93.3%, at an average of 4.5 g/m3, the aerodynamic resistance was equal to 1525 Pa.

  17. Convective drying of hawthorn fruit (Crataegus spp.): Effect of experimental parameters on drying kinetics, color, shrinkage, and rehydration capacity.

    Science.gov (United States)

    Aral, Serdar; Beşe, Ayşe Vildan

    2016-11-01

    Thin layer drying characteristics and physicochemical properties of hawthorn fruit (Crataegus spp.) were investigated using a convective dryer at air temperatures 50, 60 and 70°C and air velocities of 0.5, 0.9 and 1.3m/s. The drying process of hawthorn took place in the falling rate period, and the drying time decreased with increasing air temperature and velocity. The experimental data obtained during the drying process were fitted to eleven different mathematical models. The Midilli et al.'s model was found to be the best appropriate model for explaining the drying behavior of hawthorn fruit. Effective moisture diffusion coefficients (Deff) were calculated by Fick's diffusion model and their values varied from 2.34×10(-10)m(2)/s to 2.09×10(-9)m(2)/s. An Arrhenius-type equation was applied to determine the activation energies. While the shrinkage decreased, the rehydration ratio increased with increasing air temperature and air velocity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. LONG TERM EFFECTS OF AMELIORATIVE WORKS ON SOME SOIL QUALITY PARAMETERS FROM BAIA –MOLDOVA EXPERIMENTAL AGRICULTURAL DRAINAGE FIELD

    Directory of Open Access Journals (Sweden)

    V. Moca

    2009-10-01

    Full Text Available The soil-climatic conditions from Baia Depression – the hydrographical basin from the extra-Carpathian area of the Moldova River - have frequently determined the presence, under different forms, intensities and periods, of temporary water excess from soil. The underground drainage, as a measure of water excess control, with stagnant character, caused mainly by rainfall amounts registered for 1-5 consecutive days, was firstly arranged in pilot-experimental fields during 1972-1978. We followed the behaviour in exploitation of underground drainage technical solutions, as concerns the functional efficiency of the means of water excess removal and of the improved soil favourableness and/or suitability for crop growing.In order to assess the long-term effects of ameliorating works, applied in 1978 in the drainage field of Baia, on an area of 3.50 ha, we have qualitatively classified and estimated the albic stagnic glossic Luvosoil (S.R.T.S. – 2003, improved and unimproved. Based on this study, we have estimated the present favourableness for crops of the improved soil, as compared to unimproved soil, used as natural grassland, after an exploitation cycle of 30 years (1978- 2008.

  19. Experimental validation of energy parameters in parabolic trough collector with plain absorber and analysis of heat transfer enhancement techniques

    Science.gov (United States)

    Bilal, F. R.; Arunachala, U. C.; Sandeep, H. M.

    2018-01-01

    The quantum of heat loss from the receiver of the Parabolic Trough Collector is considerable which results in lower thermal efficiency of the system. Hence heat transfer augmentation is essential which can be attained by various techniques. An analytical model to evaluate the system with bare receiver performance was developed using MATLAB. The experimental validation of the model resulted in less than 5.5% error in exit temperature using both water and thermic oil as heat transfer fluid. Further, heat transfer enhancement techniques were incorporated in the model which included the use of twisted tape inserts, nanofluid, and a combination of both for further enhancement. It was observed that the use of evacuated glass cover in the existing setup would increase the useful heat gain up to 5.3%. Fe3O4/H2O nanofluid showed a maximum enhancement of 56% in the Nusselt number for the volume concentration of 0.6% at highest Reynolds number. Similarly, twisted tape turbulators (with twist ratio of 2) taken alone with water exhibited 59% improvement in Nusselt number. Combining both the heat transfer augmentation techniques at their best values revealed the Nusselt number enhancement up to 87%. It is concluded that, use of twisted tape with water is the best method for heat transfer augmentation since it gives the maximum effective thermal efficiency amongst all for the range of Re considered. The first section in your paper

  20. Experimental assessment of the influence of welding process parameters on Lamb wave transmission across ultrasonically welded thermoplastic composite joints

    Science.gov (United States)

    Ochôa, Pedro; Fernandez Villegas, Irene; Groves, Roger M.; Benedictus, Rinze

    2018-01-01

    One of the advantages of thermoplastic composites relative to their thermoset counterparts is the possibility of assembling components through welding. Ultrasonic welding in particular is very promising for industrialization. However, uncertainty in the fatigue and fracture behaviour of composites is still an obstacle to the full utilisation of these materials. Health monitoring is then of vital importance, and Lamb wave techniques have been widely recognised as some of the most promising approaches for that end. This paper presents the first experimental study about the influence of welding travel on the transmission of Lamb waves across ultrasonically welded thermoplastic composite joints in single-lap configuration. The main aim of this research is to start to understand how guided waves interact with the internal structure of ultrasonic welds, so that benign, manufacturing-related structural features can be distinguished from damaging ones in signal interpretation. The power transmission coefficient and the correlation coefficient proved to be suitable for analysing the wave propagation phenomena, allowing quantitative identification of small variations of weld-line thickness and intermolecular diffusion at the weld interface. The conclusions are used to develop a tentative damage detection criterion which can later on assist the design of a Lamb wave based structural health monitoring system for thermoplastic composite structures. The Lamb wave test results are backed up by phased-array inspections, which also provide some extra insight on the internal structure of ultrasonic welds.

  1. Experimental and ab initio study of the hyperfine parameters of ZnFe {sub 2}O{sub 4} with defects

    Energy Technology Data Exchange (ETDEWEB)

    Quintero, J. Melo; Salcedo Rodríguez, K. L.; Pasquevich, G. A.; Zélis, P. Mendoza; Stewart, S. J., E-mail: stewart@fisica.unlp.edu.ar; Rodríguez Torres, C. E.; Errico, L. A. [Universidad Nacional de La Plata, IFLP-CCT- La Plata-CONICET and Departamento de Física, Facultad de Ciencias Exactas, C. C. 67 (Argentina)

    2016-12-15

    We present a combined Mössbauer and ab initio study on the influence of oxygen-vacancies on the hyperfine and magnetic properties of the ZnFe {sub 2}O{sub 4} spinel ferrite. Samples with different degree of oxygen-vacancies were obtained from zinc ferrite powder that was thermally treated at different temperatures up to 650 {sup ∘}C under vacuum.Theoretical calculations of the hyperfine parameters, magnetic moments and magnetic alignment have been carried out considering different defects such as oxygen vacancies and cation inversion. We show how theoretical and experimental approaches are complementary to characterize the local structure around Fe atoms and interpret the observed changes in the hyperfine parameters as the level of defects increases.

  2. Experimental determination of submicron aerosol dry deposition velocity onto rural canopies: influence of aerosol size, of micro meteorological parameters and of the substrate

    International Nuclear Information System (INIS)

    Damay, P.

    2010-04-01

    To evaluate the impact of accidental or chronic pollutant releases on ecosystems, we must study the dry deposition of aerosols in rural areas. The lack of experimental data on the dry deposition velocity of particle sizes below 1 μm over rural environments leads to uncertainties regarding models and differences between them, which exceed one order of magnitude. The aim of this study is to develop a method, especially using an Electrical Low Pressure Impactor (Outdoor ELPIDEKATI) to determine aerosol dry deposition velocities (Vd) over rural areas through experimental measurements. This method is based on eddy covariance flux calculation and spectral analysis correction. Dry deposition velocities were obtained for atmospheric aerosols sizing from 7 nm to 2 μm, in the South-West of France on a flat terrain under varied meteorological conditions and varied substrates (maize, grass and earth). Vd was analysed as a function of the particle diameters, and the impact of micro meteorological parameters was studied. (author)

  3. Theoretical and experimental influence of aerosol assisted CVD parameters on the microstructural properties of magnetite nanoparticles and their response on the removal efficiency of arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Hernández-Salcedo, P.G.; Amézaga-Madrid, P., E-mail: patricia.amezaga@cimav.edu.mx; Monárrez-Cordero, B.E.; Antúnez-Flores, W.; Pizá-Ruiz, P.; Leyva-Porras, C.; Ornelas-Gutiérrez, C.; Miki-Yoshida, M.

    2015-09-15

    The development and optimization of methodologies to generate magnetite nanoparticles is currently an innovation topic. For a desired application such as arsenic removal from waste water, the generation of these nanostructures with specific microstructural properties is determinant. Therefore, it is necessary to understand the phenomenon during the nanoparticles formation process. Thus, in this work it is reported the influence of synthesis parameters of AACVD technique on the formation of magnetite nanoparticles. Parameters were according to: (1) synthesis temperature, (2) tubular reactor diameter, (3) concentration of the precursor solution and type of solvent, (4) carrier gas flow and (5) solvent type in the collection process. The effect of these synthesis parameters on the morphology, size and microstructure are discussed in detail and related with the mechanism of formation of the particles. Theoretical simulations were performed on two of these parameters (1 and 4). The microstructure and surface morphology of the different nanostructures obtained were characterized by field emission scanning electron and transmission electron microscopy. Subsequently two materials, were selected for further microstructural analysis. Finally, to determine the removal efficiency in the two materials the arsenic adsorption was evaluated. A major contribution of this work was the calculation of the number of spherical particles formed from a single drop of precursor solution. This calculation matched with the value found experimentally.

  4. Optimization of Experimental Conditions of the Pulsed Current GTAW Parameters for Mechanical Properties of SDSS UNS S32760 Welds Based on the Taguchi Design Method

    Science.gov (United States)

    Yousefieh, M.; Shamanian, M.; Saatchi, A.

    2012-09-01

    Taguchi design method with L9 orthogonal array was implemented to optimize the pulsed current gas tungsten arc welding parameters for the hardness and the toughness of super duplex stainless steel (SDSS, UNS S32760) welds. In this regard, the hardness and the toughness were considered as performance characteristics. Pulse current, background current, % on time, and pulse frequency were chosen as main parameters. Each parameter was varied at three different levels. As a result of pooled analysis of variance, the pulse current is found to be the most significant factor for both the hardness and the toughness of SDSS welds by percentage contribution of 71.81 for hardness and 78.18 for toughness. The % on time (21.99%) and the background current (17.81%) had also the next most significant effect on the hardness and the toughness, respectively. The optimum conditions within the selected parameter values for hardness were found as the first level of pulse current (100 A), third level of background current (70 A), first level of % on time (40%), and first level of pulse frequency (1 Hz), while they were found as the second level of pulse current (120 A), second level of background current (60 A), second level of % on time (60%), and third level of pulse frequency (5 Hz) for toughness. The Taguchi method was found to be a promising tool to obtain the optimum conditions for such studies. Finally, in order to verify experimental results, confirmation tests were carried out at optimum working conditions. Under these conditions, there were good agreements between the predicted and the experimental results for the both hardness and toughness.

  5. Détermination expérimentale des paramètres de Wilson Experimental Dertermination of Wilson Parameters

    Directory of Open Access Journals (Sweden)

    Monfort J.-P.

    2006-11-01

    Full Text Available La volabilité relative ait; =(yilxil(Y;lxi des constituants d'un mélange binaire a été mesurée à partir d'un nouveau dispositif expérimental, on reporte les données d'équilibre liquide-vapeur obtenues à 45'C de plusieurs binaires : toluène-acétoni-trile, benzène-acétonitrile et benzène-n-heptane. En ajustant à l'équation de Wilson les données expérimentales de «i/; de ces constituants ainsi que des volatilités relatives des constituants des mélanges d'hydrocarbures-alcools, obtenues dans un précédent travail, on calcule les paramètres énergétiques. La prédiction des points de bulle de mélanges binaires et ternaires obtenue à partir de ces paramètres est satisfaisante. La méthode expérimentale ainsi proposée convient particulièrement pour la sélection des solvant extractifs utilisés dans la distillation extractive. From a new expérimental method, relative volatilities aiti = (yilxil(yilxi for a binary mixture are obtained; vapor-liquid equilibrium data are presented for several systems, i.e. toluene-acétonitrile, benzene-acétonitrile and benzene-n-heptane at 45°C. The two adjustable energyparameters of thé Wilson équation, are obtained by adopting thé «,/j data for these binary mixtures and for alcohol-hydrocarbon mixtures previously studied. Theresults obtained in predicting bubble-pressure data for binary and ternary mixtures are consistent with experimental data.

  6. Thymic function and T cell parameters in a natural human experimental model of seasonal infectious diseases and nutritional burden

    Directory of Open Access Journals (Sweden)

    Morgan Gareth

    2011-06-01

    Full Text Available Abstract Background The study exploits a natural human experimental model of subsistence farmers experiencing chronic and seasonally modified food shortages and infectious burden. Two seasons existed, one of increased deprivation and infections (Jul-Dec, another of abundance and low infections (Jan-Jun; referred to as the hungry/high infection and harvest/low infection seasons respectively. Prior analysis showed a 10-fold excess in infectious disease associated mortality in young adults born in the hungry/high infection versus harvest/low infection season, and reduced thymic output and T cell counts in infancy. Here we report findings on the role of early life stressors as contributors to the onset of T cell immunological defects in later life. Methods We hypothesised that season of birth effects on thymic function and T cell immunity would be detectable in young adults since Kaplan-Meier survival curves indicated this to be the time of greatest mortality divergence. T cell subset analyses by flow-cytometry, sjTRECs, TCRVβ repertoire and telomere length by PCR, were performed on samples from 60 males (18-23 y selected to represent births in the hungry/high infection and harvest/low infection Results Total lymphocyte counts were normal and did not differ by birth season. CD3+ and CD4+ but not CD8+ counts were lower for those born during the hungry/high infection season. CD8+ telomere length also tended to be shorter. Overall, CD8+ TCRVβ repertoire skewing was observed with 'public' expressions and deletions seen in TCRVβ12/22 and TCRVβ24, respectively but no apparent effect of birth season. Conclusions We conclude that, although thymic function was unchanged, the CD4+ and CD3+ counts, and CD8+ telomere length results suggested that aspects of adult T cell immunity were under the influence of early life stressors. The endemicity of CMV and HBV suggested that chronic infections may modulate immunity through T cell repertoire development. The

  7. Development of a dual-energy computed tomography quality control program: Characterization of scanner response and definition of relevant parameters for a fast-kVp switching dual-energy computed tomography system.

    Science.gov (United States)

    Nute, Jessica L; Jacobsen, Megan C; Stefan, Wolfgang; Wei, Wei; Cody, Dianna D

    2018-04-01

    A prototype QC phantom system and analysis process were developed to characterize the spectral capabilities of a fast kV-switching dual-energy computed tomography (DECT) scanner. This work addresses the current lack of quantitative oversight for this technology, with the goal of identifying relevant scan parameters and test metrics instrumental to the development of a dual-energy quality control (DEQC). A prototype elliptical phantom (effective diameter: 35 cm) was designed with multiple material inserts for DECT imaging. Inserts included tissue equivalent and material rods (including iodine and calcium at varying concentrations). The phantom was scanned on a fast kV-switching DECT system using 16 dual-energy acquisitions (CTDIvol range: 10.3-62 mGy) with varying pitch, rotation time, and tube current. The circular head phantom (22 cm diameter) was scanned using a similar protocol (12 acquisitions; CTDIvol range: 36.7-132.6 mGy). All acquisitions were reconstructed at 50, 70, 110, and 140 keV and using a water-iodine material basis pair. The images were evaluated for iodine quantification accuracy, stability of monoenergetic reconstruction CT number, noise, and positional constancy. Variance component analysis was used to identify technique parameters that drove deviations in test metrics. Variances were compared to thresholds derived from manufacturer tolerances to determine technique parameters that had a nominally significant effect on test metrics. Iodine quantification error was largely unaffected by any of the technique parameters investigated. Monoenergetic HU stability was found to be affected by mAs, with a threshold under which spectral separation was unsuccessful, diminishing the utility of DECT imaging. Noise was found to be affected by CTDIvol in the DEQC body phantom, and CTDIvol and mA in the DEQC head phantom. Positional constancy was found to be affected by mAs in the DEQC body phantom and mA in the DEQC head phantom. A streamlined scan protocol

  8. Experimental determination of Henry's law constants of difluoromethane (HFC-32 and the salting-out effects in aqueous salt solutions relevant to seawater

    Directory of Open Access Journals (Sweden)

    S. Kutsuna

    2017-06-01

    Full Text Available Gas-to-water equilibrium coefficients, KeqS (in M atm−1, of difluoromethane (CH2F2, a hydrofluorocarbon refrigerant (HFC-32, in aqueous salt solutions relevant to seawater were determined over a temperature (T range from 276 to 313 K and a salinity (S range up to 51 ‰ by means of an inert-gas stripping method. From the van't Hoff equation, the KeqS value in water, which corresponds to the Henry's law constant (KH, at 298 K was determined to be 0.065 M atm−1. The salinity dependence of KeqS (the salting-out effect, ln(KH∕KeqS, did not obey the Sechenov equation but was proportional to S0. 5. Overall, the KeqS(T value was expressed by ln(KeqS(T  =  −49.71 + (77.70 − 0.134  ×  S0. 5  ×  (100∕T + 19.14  ×  ln(T∕100. By using this equation in a lower-tropospheric semi-hemisphere (30–90 °S of the Advanced Global Atmospheric Gases Experiment (AGAGE 12-box model, we estimated that 1 to 4 % of the atmospheric burden of CH2F2 resided in the ocean mixed layer and that this percentage was at least 4 % in the winter; dissolution of CH2F2 in the ocean may partially influence estimates of CH2F2 emissions from long-term observational data of atmospheric CH2F2 concentrations.

  9. Development and experimental evaluation of models for low capillary number two-phase flows in rough walled fractures relevant to natural gradient conditions

    International Nuclear Information System (INIS)

    Glass, R.J.; Yarrington, L.; Nicholl, M.J.

    1997-09-01

    The major results from SNL's Conceptual Model Development and Validation Task (WBS 1.2.5.4.6) as developed through exploration of small scale processes were synthesized in Glass et al. to give guidance to Performance Assessment on improving conceptual models for isothermal flow in unsaturated, fractured rock. There, pressure saturation and relative permeability curves for single fractures were proposed to be a function of both fracture orientation within the gravity field and initial conditions. We refer the reader to Glass et al. for a discussion of the implications of this behavior for Performance Assessment. The scientific research we report here substantiates this proposed behavior. We address the modeling of phase structure within fractures under natural gradient conditions relevant to unsaturated flow through fractures. This phase structure underlies the calculation of effective properties for individual fractures and hence fracture networks as required for Performance Assessment. Standard Percolation (SP) and Invasion Percolation (IP) approaches have been recently proposed to model the underlying phase saturation structures within the individual fractures during conditions of two-phase flow. Subsequent analysis of these structures yields effective two-phase pressure-saturation and relative permeability relations for the fracture. However, both of these approaches yield structures that are at odds with physical reality as we see in experiments and thus effective properties calculated from these structures are in error. Here we develop and evaluate a Modified Invasion Percolation (MIP) approach to better model quasi-static immiscible displacement in fractures. The effects of gravity, contact angle, local aperature field geometry, and local in-plane interfacial curvature between phases are included in the calculation of invasion pressure for individual sites in a discretized aperture field

  10. Relevance of physical fitness levels and exercise-related beliefs for self-reported and experimental pain in fibromyalgia: an explorative study.

    Science.gov (United States)

    de Bruijn, Saskia T; van Wijck, Albert J M; Geenen, Rinie; Snijders, Tom J; van der Meulen, Wout J T M; Jacobs, Johannes W G; Veldhuijzen, Dieuwke Swaantje

    2011-09-01

    It has been suggested that low physical fitness is a contributor to pain in fibromyalgia and that exercise-related beliefs play a role in the persistence of this association. Yet the association between physical fitness and pain is hardly explored in detail. The aim of this exploratory study in patients with fibromyalgia was to investigate the association of physical fitness levels with self-reported and experimental pain as well as with pain catastrophizing and activity-avoidance beliefs. Physical fitness of 18 patients with fibromyalgia was examined using maximal ergocycling and the 6-minute walking test (6MWT). Pain intensity was assessed using self-report scales and quantitative sensory testing. A reduced walking distance on the 6MWT was correlated with more severe self-reported pain on the Fibromyalgia Impact Questionnaire (r = -0.52, P physically fit and experienced more severe pain. The results demonstrate some associations between physical fitness and pain in fibromyalgia and point to the importance of activity avoidance. Although the causal directionality of the associations needs substantiation in clinical research, the findings support the notion that low fitness and activity-avoidance beliefs should be targeted while treating pain in fibromyalgia.

  11. Experimental study of divertor plasma-facing components damage under a combination of pulsed and quasi-stationary heat loads relevant to expected transient events at ITER

    International Nuclear Information System (INIS)

    Klimov, N S; Podkovyrov, V L; Kovalenko, D V; Zhitlukhin, A M; Barsuk, V A; Mazul, I V; Giniyatulin, R N; Kuznetsov, V Ye; Riccardi, B; Loarte, A; Merola, M; Koidan, V S; Linke, J; Landman, I S; Pestchanyi, S E; Bazylev, B N

    2011-01-01

    This paper concerns the experimental study of damage of ITER divertor plasma-facing components (PFCs) under a combination of pulsed plasma heat loads (representative of controlled ITER type I edge-localized modes (ELMs)) and quasi-stationary heat loads (representative of the high heat flux (HHF) thermal fatigue expected during ITER normal operations and slow transient events). The PFC's tungsten armor damage under pulsed plasma exposure was driven by (i) the melt layer motion, which leads to bridges formation between neighboring tiles and (ii) the W brittle failure giving rise to a stable crack pattern on the exposed surface. The crack width reaches a saturation value that does not exceed some tens of micrometers after several hundreds of ELM-like pulses. HHF thermal fatigue tests have shown (i) a peeling-off of the re-solidified material due to its brittle failure and (ii) a significant widening (up to 10 times) of the cracks and the formation of additional cracks.

  12. Experimental study of the vortex-induced vibration of drilling risers under the shear flow with the same shear parameter at the different Reynolds numbers.

    Science.gov (United States)

    Liangjie, Mao; Qingyou, Liu; Shouwei, Zhou

    2014-01-01

    A considerable number of studies for VIV under the uniform flow have been performed. However, research on VIV under shear flow is scarce. An experiment for VIV under the shear flow with the same shear parameter at the two different Reynolds numbers was conducted in a deep-water offshore basin. Various measurements were obtained by the fiber bragg grating strain sensors. Experimental data were analyzed by modal analysis method. Results show several valuable features. First, the corresponding maximum order mode of the natural frequency for shedding frequency is the maximum dominant vibration mode and multi-modal phenomenon is appeared in VIV under the shear flow, and multi-modal phenomenon is more apparent at the same shear parameter with an increasing Reynolds number under the shear flow effect. Secondly, the riser vibrates at the natural frequency and the dominant vibration frequency increases for the effect of the real-time tension amplitude under the shear flow and the IL vibration frequency is the similar with the CF vibration frequency at the Reynolds number of 1105 in our experimental condition and the IL dominant frequency is twice the CF dominant frequency with an increasing Reynolds number. In addition, the displacement trajectories at the different locations of the riser appear the same shape and the shape is changed at the same shear parameter with an increasing Reynolds number under the shear flow. The diagonal displacement trajectories are observed at the low Reynolds number and the crescent-shaped displacement trajectories appear with an increasing Reynolds number under shear flow in the experiment.

  13. Experimental study of the vortex-induced vibration of drilling risers under the shear flow with the same shear parameter at the different Reynolds numbers.

    Directory of Open Access Journals (Sweden)

    Mao Liangjie

    Full Text Available A considerable number of studies for VIV under the uniform flow have been performed. However, research on VIV under shear flow is scarce. An experiment for VIV under the shear flow with the same shear parameter at the two different Reynolds numbers was conducted in a deep-water offshore basin. Various measurements were obtained by the fiber bragg grating strain sensors. Experimental data were analyzed by modal analysis method. Results show several valuable features. First, the corresponding maximum order mode of the natural frequency for shedding frequency is the maximum dominant vibration mode and multi-modal phenomenon is appeared in VIV under the shear flow, and multi-modal phenomenon is more apparent at the same shear parameter with an increasing Reynolds number under the shear flow effect. Secondly, the riser vibrates at the natural frequency and the dominant vibration frequency increases for the effect of the real-time tension amplitude under the shear flow and the IL vibration frequency is the similar with the CF vibration frequency at the Reynolds number of 1105 in our experimental condition and the IL dominant frequency is twice the CF dominant frequency with an increasing Reynolds number. In addition, the displacement trajectories at the different locations of the riser appear the same shape and the shape is changed at the same shear parameter with an increasing Reynolds number under the shear flow. The diagonal displacement trajectories are observed at the low Reynolds number and the crescent-shaped displacement trajectories appear with an increasing Reynolds number under shear flow in the experiment.

  14. Affinity of Smectite and Divalent Metal Ions (Mg(2+), Ca(2+), Cu(2+)) with L-leucine: An Experimental and Theoretical Approach Relevant to Astrobiology.

    Science.gov (United States)

    Pandey, Pramod; Pant, Chandra Kala; Gururani, Kavita; Arora, Priyanka; Pandey, Neetu; Bhatt, Preeti; Sharma, Yogesh; Negi, Jagmohan Singh; Mehata, Mohan Singh

    2015-12-01

    Earth is the only known planet bestowed with life. Several attempts have been made to explore the pathways of the origin of life on planet Earth. The search for the chemistry which gave rise to life has given answers related to the formation of biomonomers, and their adsorption on solid surfaces has gained much attention for the catalysis and stabilization processes related to the abiotic chemical evolution of the complex molecules of life. In this communication, surface interactions of L-leucine (Leu) on smectite (SMT) group of clay (viz. bentonite and montmorillonite) and their divalent metal ion (Mg(2+), Ca(2+) and Cu(2+)) incorporated on SMT has been studied to find the optimal conditions of time, pH, and concentration at ambient temperature (298 K). The progress of adsorption was followed spectrophotometrically and further characterized by FTIR, SEM/EDS and XRD. Leu, a neutral/non polar amino acid, was found to have more affinity in its zwitterionic form towards Cu(2+)- exchanged SMT and minimal affinity for Mg(2+)- exchanged SMT. The vibrational frequency shifts of -NH3 (+) and -COO(-) favor Van der Waal's forces during the course of surface interaction. Quantum calculations using density functional theory (DFT) have been applied to investigate the absolute value of metal ion affinities of Leu (Leu-M(2+) complex, M = Mg(2+), Ca(2+), Cu(2+)) with the help of their physico-chemical parameters. The hydration effect on the relative stability and geometry of the individual species of Leu-M(2+) × (H2O)n, (n =2 and 4) has also been evaluated within the supermolecule approach. Evidence gathered from investigations of surface interactions, divalent metal ions affinities and hydration effects with biomolecules may be important for better understanding of chemical evolution, the stabilization of biomolecules on solid surfaces and biomolecular-metal interactions. These results may have implications for understanding the origin of life and the preservation of

  15. An experimental study of the effects of combined exposure to microwave and heat on gene expression and sperm parameters in mice

    Directory of Open Access Journals (Sweden)

    Faezeh A Gohari

    2017-01-01

    Full Text Available Objectives: Separate exposure to microwaves (MWs or heat had effects on expression levels of Bax and Bcl-2 and sperm parameters in studied group. Aims: The objectives of this research were to determine the effects of separate and combined exposure to 900-MHz MW (as representative of cell phone radiation and heat on gene expression and spermogram of male mice. Settings and Design: This experimental animal study was conducted in the school of public health. Materials and Methods: The study was done on 12 male mice randomly divided into four groups (21–23 g: control, test group 1 with separate exposure to 900-MHz MW, test group 2 with separate exposure to hot and sultry climate, and test group 3 with simultaneous whole body exposures to 900-MHz MW and hot and sultry climate. In all studied groups, gene expression and sperm parameters were measured. Results: Tissue samples in all test groups showed integrity of the seminiferous tubule followed by all types of germ line cells. Significant increases in the number of dead sperms in mice with separate exposure to heat were observed in comparison with the other studied groups (P < 0.05. The ratio of Bax expression was elevated to 0.015 ± 0.006 in mice after combined exposures to 900-MHz MW and heat. Conclusion: Separate and combined exposure to 900-MHz MW and heat may induce adverse effects on sperm parameters and gene expression of studied male mice.

  16. Tension-free vaginal tape versus lata fascia sling: The importance of transvulvar ultrasound in the assessment of relevant anatomical parameters in treatment of women with stress urinary incontinence

    Directory of Open Access Journals (Sweden)

    Frederico Teixeira Brandt

    2009-01-01

    Full Text Available Objective: To describe the relevance of transvulvar ultrasound in the assessment of anatomical differences induced by the lata fascia sling (LFS and tension-free vaginal tape (TVT procedures. Materials and Methods: Forty women with stress urinary incontinence (SUI, aged 30 to 60 years, have been treated with either LFS (20 patients or TVT (20 patients. The transvulvar ultrasound of the urethrovesical junction (UVJ and proximal urethra (PU has been used as the main investigational tool both pre- and post-operatively. The studied parameters were the vertical (VUVJD and horizontal (HUVJD UVJ distances, the pubourethral distance (PUD and the PU length. Results: The VUVJD did not vary significantly after the LFS surgery (P=0.10. The PUD became shorter (P=0.001 and the HUVJD became shorter only at rest (P=0.03 after the correction by LFS. The TVT procedure has led to shortening of the VUVJ displacement (P=0.0005 and of the PU length (P=0.02. Conclusions: The transvulvar ultrasound was of utmost importance in the demonstration that both the LFS and TVT surgical procedures elongate the PU, even though the LFS technique does it more efficiently. The LFS technique focus more on shortening the PUD and the TVT procedure focus more on the correction of the vertical UVJ displacement.

  17. Inventory parameters

    CERN Document Server

    Sharma, Sanjay

    2017-01-01

    This book provides a detailed overview of various parameters/factors involved in inventory analysis. It especially focuses on the assessment and modeling of basic inventory parameters, namely demand, procurement cost, cycle time, ordering cost, inventory carrying cost, inventory stock, stock out level, and stock out cost. In the context of economic lot size, it provides equations related to the optimum values. It also discusses why the optimum lot size and optimum total relevant cost are considered to be key decision variables, and uses numerous examples to explain each of these inventory parameters separately. Lastly, it provides detailed information on parameter estimation for different sectors/products. Written in a simple and lucid style, it offers a valuable resource for a broad readership, especially Master of Business Administration (MBA) students.

  18. Typical parameters of the plasma chemical similarity in non-isothermal reactive plasmas

    International Nuclear Information System (INIS)

    Gundermann, S.; Jacobs, H.; Miethke, F.; Rutsher, A.; Wagner, H.E.

    1996-01-01

    The substance of physical similarity principles is contained in parameters which govern the comparison of different realizations of a model device. Because similarity parameters for non-isothermal plasma chemical reactors are unknown to a great extent, an analysis of relevant equations is given together with some experimental results. Modelling of the reactor and experimental results for the ozone synthesis are presented

  19. The role of the experimental data base used to identify material parameters in predicting the cyclic plastic response of an austenitic steel

    International Nuclear Information System (INIS)

    Djimli, Lynda; Taleb, Lakhdar; Meziani, Salim

    2010-01-01

    The first objective of this paper investigates the influence of the previous strain history on ratcheting. New tests were performed where different strain-controlled histories have been applied prior to ratcheting tests. It is demonstrated that under the same conditions, one can observe ratcheting, plastic shakedown or elasticity according to the prior strain-controlled history. The second objective points out the correlation between the experimental data base devoted to the identification of the material parameters and the quality of the predictions in cyclic plasticity. The results suggest that the choice of the tests should be closely linked to the capabilities of the model. In particular, the presence of non proportional strain-controlled tests in the data base may be not a good choice if the model itself is not able to represent explicitly such a character. All tests considered here were performed on 304L SS at room temperature.

  20. Comprehensive distributed-parameters modeling and experimental validation of microcantilever-based biosensors with an application to ultrasmall biological species detection

    International Nuclear Information System (INIS)

    Faegh, Samira; Jalili, Nader

    2013-01-01

    Nanotechnological advancements have made a great contribution in developing label-free and highly sensitive biosensors. The detection of ultrasmall adsorbed masses has been enabled by such sensors which transduce molecular interaction into detectable physical quantities. More specifically, microcantilever-based biosensors have caught widespread attention for offering a label-free, highly sensitive and inexpensive platform for biodetection. Although there are a lot of studies investigating microcantilever-based sensors and their biological applications, a comprehensive mathematical modeling and experimental validation of such devices providing a closed form mathematical framework is still lacking. In almost all of the studies, a simple lumped-parameters model has been proposed. However, in order to have a precise biomechanical sensor, a comprehensive model is required being capable of describing all phenomena and dynamics of the biosensor. Therefore, in this study, an extensive distributed-parameters modeling framework is proposed for the piezoelectric microcantilever-based biosensor using different methodologies for the purpose of detecting an ultrasmall adsorbed mass over the microcantilever surface. An optimum modeling methodology is concluded and verified with the experiment. This study includes three main parts. In the first part, the Euler–Bernoulli beam theory is used to model the nonuniform piezoelectric microcantilever. Simulation results are obtained and presented. The same system is then modeled as a nonuniform rectangular plate. The simulation results are presented describing model's capability in the detection of an ultrasmall mass. Finally the last part presents the experimental validation verifying the modeling results. It was shown that plate modeling predicts the real situation with a degree of precision of 99.57% whereas modeling the system as an Euler–Bernoulli beam provides a 94.45% degree of precision. The detection of ultrasmall

  1. Experimental investigation of performance and emissions of a VCR diesel engine fuelled with n-butanol diesel blends under varying engine parameters.

    Science.gov (United States)

    Nayyar, Ashish; Sharma, Dilip; Soni, Shyam Lal; Mathur, Alok

    2017-09-01

    The continuous rise in the cost of fossil fuels as well as in environmental pollution has attracted research in the area of clean alternative fuels for improving the performance and emissions of internal combustion (IC) engines. In the present work, n-butanol is treated as a bio-fuel and investigations have been made to evaluate the feasibility of replacing diesel with a suitable n-butanol-diesel blend. In the current research, an experimental investigation was carried out on a variable compression ratio CI engine with n-butanol-diesel blends (10-25% by volume) to determine the optimum blending ratio and optimum operating parameters of the engine for reduced emissions. The best results of performance and emissions were observed for 20% n-butanol-diesel blend (B20) at a higher compression ratio as compared to diesel while keeping the other parameters unchanged. The observed deterioration in engine performance was within tolerable limits. The reductions in smoke, nitrogen oxides (NO x ), and carbon monoxide (CO) were observed up to 56.52, 17.19, and 30.43%, respectively, for B20 in comparison to diesel at rated power. However, carbon dioxide (CO 2 ) and hydrocarbons (HC) were found to be higher by 17.58 and 15.78%, respectively, for B20. It is concluded that n-butanol-diesel blend would be a potential fuel to control emissions from diesel engines. Graphical abstract ᅟ.

  2. An investigation of the effects of experimental parameters on the closed-loop control of photoionization/dissociation processes in acetophenone

    Science.gov (United States)

    Graham, Paul; Menkir, Getahun; Levis, Robert J.

    2003-06-01

    The photodissociation channels of acetophenone (C 6H 5)CO(CH 3), can be controlled by the use of tailored strong-field laser pulses together with a feedback loop incorporating an adaptive algorithm. This optimal control strategy is used to selectively cleave either the OCCH 3 or OCC 6H 5 bonds, monitored by detecting either mass 105 or 77, respectively. Varying the pulse chirp and duration prior to optimization is shown to affect the dynamic range of control. We show that it is possible to decrease the search space by limiting the retardance range of the spatial light modulator (SLM), or by decreasing the number of frequency elements manipulated by the SLM, and still achieve a certain degree of control over acetophenone dissociation. Performing consecutive experiments with identical experimental parameters and search criteria reveals that the learning algorithm may find solutions that have the same degree of control (various local solutions), with either similar SLM retardances or markedly different retardances. Comparison of the dynamic range of control between single-parameter optimizations (pulse energy and duration) with the tailored electric field profiles generated by the adaptive algorithm reveals an enhancement in the control of reaction product distributions in the latter scheme.

  3. Numerical Experimentation to Develop Design and Operational Parameters for Skimming Wells: A Case Study of the Chaj Doab of Punjab, Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam

    2015-07-01

    Full Text Available In the present study, MODFLOW-MT3D groundwater model was employed to perform numerical experimentation to develop design and operational parameters for SW (Skimming Wells based on hydrogeology and groundwater salinity conditions of Chaj Doab, Punjab, Pakistan. Numerical experimentation resulted in: (i a 1-strainer SW with discharge of 14 l/s (litres per second and penetration of 30% resulted in more saltwater upconing at 8 hours/day well operation compared to that occurred at 4 hours/day operation; (ii a 1-strainer well with penetration of 30% and operation of 8 hours/day caused higher saltwater upconing at 14 l/s discharge compared to that at 9 l/s discharge; (iii a 4-strainer well with penetration of 30% and operation of 8 hours/day also caused more saltwater upconing at 14 l/s well discharge compared to that at 9 l/s discharge. Similar trend was found for a 8- strainer well; and (iv 1- or 4- or 8-strainer well with 30-60% penetration, 9-14 l/s discharge and 4-8 hours/day operation could provide pumped groundwater of salinity less than 1000 ppm. Considering hydro-chemical performance and costs of wells, a 4-strainer well with 30% penetration, 9- 14 l/s discharge and 4-8 hours/day operation is recommended to skim groundwater of salinity less than 1000 ppm in Chaj Doab of Punjab, Pakistan

  4. Influence of Experimental Parameters Using the Dip-Coating Method on the Barrier Performance of Hybrid Sol-Gel Coatings in Strong Alkaline Environments

    Directory of Open Access Journals (Sweden)

    Rita B. Figueira

    2015-04-01

    Full Text Available Previous studies have shown that the barrier effect and the performance of organic-inorganic hybrid (OIH sol-gel coatings are highly dependent on the coating deposition method as well as on the processing conditions. However, studies on how the coating deposition method influences the barrier properties in alkaline environments are scarce. The aim of this experimental research was to study the influence of experimental parameters using the dip-coating method on the barrier performance of an OIH sol-gel coating in contact with simulated concrete pore solutions (SCPS. The influence of residence time (Rt, a curing step between each dip step and the number of layers of sol-gel OIH films deposited on hot-dip galvanized steel to prevent corrosion in highly alkaline environments was studied. The barrier performance of these OIH sol-gel coatings, named U(400, was assessed in the first instants of contact with SCPS, using electrochemical impedance spectroscopy and potentiodynamic methods. The durability and stability of the OIH coatings in SCPS was monitored during eight days by macrocell current density. The morphological characterization of the surface was performed by Scanning Electronic Microscopy before and after exposure to SCPS. Glow Discharge Optical Emission Spectroscopy was used to investigate the thickness of the U(400 sol-gel coatings as a function of the number of layers deposited with and without Rt in the coatings thickness.

  5. Experimental Research on The Deformability of a Geological Material: Initial Characterisation and Identification of Parameters; Estudio Experimental de la Deformabilidad de un Material Geologico: Caracterizacion Inicial e Identificacion de Parametros

    Energy Technology Data Exchange (ETDEWEB)

    Villar, M.V.; Udias, A.; Canamon, I.; Robles, J.

    2006-07-01

    This document reflects the work performed at CIEMAT (Engineered and Geological Barriers Group) in the framework of the RTD Project BTE2002-04244-C02-02 (DEF-NOSAT). The first phase of the project consisted on the selection and characterisation of a geological material fitted for unsaturated triaxial testing. The result obtained during this phase gave place to the selection of a silty clay from Alcala de Henares (Madrid, Spain). Compaction and permeability tests were performed as well as studies on mixtures of this soil with sand. With the selected mixtures (70/30 and 50/50 percent sand/soil) isotropic compression tests were carried out in the saturated sample. The results of these tests have allowed the determination of some of the parameters needed to model the mechanical behaviour of the soil. The report includes also a brief description of a methodology developed in the Department of Applied Mathematics and Computer Methods of the Universidad Politecnica de Madrid for getting these parameters by optimisation of the experimental results, as well as the results obtained. (Author) 25 refs.

  6. Optimization of Monte Carlo particle transport parameters and validation of a novel high throughput experimental setup to measure the biological effects of particle beams.

    Science.gov (United States)

    Patel, Darshana; Bronk, Lawrence; Guan, Fada; Peeler, Christopher R; Brons, Stephan; Dokic, Ivana; Abdollahi, Amir; Rittmüller, Claudia; Jäkel, Oliver; Grosshans, David; Mohan, Radhe; Titt, Uwe

    2017-11-01

    Accurate modeling of the relative biological effectiveness (RBE) of particle beams requires increased systematic in vitro studies with human cell lines with care towards minimizing uncertainties in biologic assays as well as physical parameters. In this study, we describe a novel high-throughput experimental setup and an optimized parameterization of the Monte Carlo (MC) simulation technique that is universally applicable for accurate determination of RBE of clinical ion beams. Clonogenic cell-survival measurements on a human lung cancer cell line (H460) are presented using proton irradiation. Experiments were performed at the Heidelberg Ion Therapy Center (HIT) with support from the Deutsches Krebsforschungszentrum (DKFZ) in Heidelberg, Germany using a mono-energetic horizontal proton beam. A custom-made variable range selector was designed for the horizontal beam line using the Geant4 MC toolkit. This unique setup enabled a high-throughput clonogenic assay investigation of multiple, well defined dose and linear energy transfer (LETs) per irradiation for human lung cancer cells (H460) cultured in a 96-well plate. Sensitivity studies based on application of different physics lists in conjunction with different electromagnetic constructors and production threshold values to the MC simulations were undertaken for accurate assessment of the calculated dose and the dose-averaged LET (LET d ). These studies were extended to helium and carbon ion beams. Sensitivity analysis of the MC parameterization revealed substantial dependence of the dose and LET d values on both the choice of physics list and the production threshold values. While the dose and LET d calculations using FTFP_BERT_LIV, FTFP_BERT_EMZ, FTFP_BERT_PEN and QGSP_BIC_EMY physics lists agree well with each other for all three ions, they show large differences when compared to the FTFP_BERT physics list with the default electromagnetic constructor. For carbon ions, the dose corresponding to the largest LET d

  7. Experimental research on the influence of system parameters on the composition shift for zeotropic mixture (isobutane/pentane) in a system occurring phase change

    International Nuclear Information System (INIS)

    Bao, Junjiang; Zhao, Li

    2016-01-01

    Highlights: • The influence of system parameters on the composition shift for zeotropic mixture is studied. • Zeotropic mixture isobutane/pentane is selected as the working fluids. • Circulating composition and charge have the inverse proportion relationship. • The relationship between circulating composition and charge composition is linear. - Abstract: Zeotropic mixture can improve the performance of the thermodynamic cycle ascribed to the better temperature match during the heat transfer process with the characteristics of temperature glide during evaporation and condensing processes. Another characteristic of zeotropic mixture is composition shift. Composition shift means that the circulating composition and charge composition is different and is mainly caused by the two-phase hold-up and different solubility in lubricating oil. The existence of composition shift will affect the design and operation of thermodynamic system. The previous study gave little information about the influence of system parameters on the composition shift in a system occurring phase change. This paper mainly discuss the influence of system parameters on the composition shift for zeotropic mixture in a system occurring phase change as well as the validation of the linear relationship between the circulating composition and the charge composition and the inverse proportion relationship between the circulating composition and the charge mass found based on our previous theory study (Zhao and Bao, 2014). With isobutane and pentane as the research object, the impact of the key system parameters (hot water temperature, mass flow rate of hot water, feed pump frequency, cold water temperature and evaporator length) on composition shift are experimentally carried out. The results show that when the hot water temperature, mass flow rate of hot water and evaporator length increase and cold water temperature decreases, circulating composition will increase. For feed pump frequency, when

  8. The electronic system for mechanical oscillation parameters registration

    Directory of Open Access Journals (Sweden)

    Bulavin L. A.

    2008-08-01

    Full Text Available On the basis of the 8-bit microcontroller Microchip PIC16F630 the digital electronic device for harmonic oscillation parameters registration was developed. The device features are simple electric circuit and high operating speed (response time is less than 10 microseconds. The relevant software for the computer-controlled recording of harmonic oscillation parameters was designed. The device can be used as a part of the experimental setup for consistent fluids rheological parameters measurements.

  9. Evaluation of Reaction Parameters of the Phenol Steam Reforming over Ni/Co on ZrO2 Using the Full Factorial Experimental Design

    Directory of Open Access Journals (Sweden)

    Walid Nabgan

    2016-08-01

    Full Text Available Full factorial experimental design with 32 runs was used to investigate the significant and interaction variable of the reaction parameters on phenol steam reforming toward hydrogen production. Effects of selected factors on the phenol conversion (Y1 and hydrogen yield (Y2 were evaluated. These factors were as follows: (A temperature (500 and 800 °C; (B feed flow rate (0.16–0.46 mL/min; (C catalyst weight (0.1–0.3 g; (D Ni-Co ratio (0–1; and (E phenol concentration in the feed (2–10 wt %. Ni and Co over ZrO2 support for catalytic performance of phenol steam reforming (SRP was prepared by the impregnation method. The result indicated that all the main independent variables had significant influence on the dependent variable of Y1 and Y2 with a range of 2.7%–96.8% and 21.4%–72.4%, respectively. Additionally, some interaction variables like AE, BE, CE, and DE have also influenced the Y1 and Y2 responses. This design showed that the best initial conditions that produced maximum Y1 and Y2 responses were at 800 °C, 0.16 mL/min feed flow rate, 0.3 g of catalyst, 0 ratio of Ni-Co (Co/ZrO2, and 10 wt % of phenol in the feed, where the phenol conversion was predicted to be 94.98% and the hydrogen yield was predicted to be 67.4%. Within the limits the variables were examined, a regression model which well-fitted the experimental data was proposed. The regression model were reduced to simplify and to get the significant regression coefficient with p-value less than 0.05.

  10. Experimental investigations on the influence of the photocathode laser pulse parameters on the electron bunch quality in an RF-photoelectron source

    International Nuclear Information System (INIS)

    Haenel, Marc

    2010-06-01

    Free Electron Lasers based on the SASE principle like the European XFEL require electron bunches having peak currents of several kiloamperes as well as very low transverse emittance. While high peak currents can be generated using longitudinal bunch compression techniques, the transverse emittance must have values as low as 1mmmrad already at the source. The development of electron sources fulfilling these demanding specifications is the goal of the Photo Injector Test Facility (PITZ) in DESY, Zeuthen site. The key component of a photoinjector is the electron gun cavity where the electrons bunches are generated and immediately accelerated. The extraction of the electrons is based on the photoelectric effect of the cathode which requires a laser system having special capabilities. In the first part of the thesis, measurements are presented which were performed to investigate whether the laser and the laser transport system fulfill these requirements. The second part of the thesis is dedicated to simulations as well as experimental studies on the impact of the temporal and spatial parameters of the laser pulses on the electron bunch quality. This influence is possible because the response time of the Cs 2 Te photocathode is short compared to the laser pulse duration. Based on these investigations, suggestions for improvements are given and tolerances for the laser pulse properties are defined. (orig.)

  11. Effects of Cuminum cyminum L. essential oil on some epididymal sperm parameters and histopathology of testes following experimentally induced copper poisoning in mice.

    Science.gov (United States)

    Sakhaee, E; Emadi, L; Azari, O; Kheirandish, R; Esmaili Nejad, M R; Shafiei Bafti, H

    2016-06-01

    Copper overload can cause sperm cell damage by inducing oxidative stress. On the other hand, cumin has a good antioxidant potential. Therefore, the aim of this study was to evaluate the effects of cumin on sperm quality and testicular tissue following experimentally induced copper poisoning in mice. Forty-eight mature male mice were divided into four equal groups as follows: group Cu which received 0.1 ml copper sulphate at dose of 100 mg kg(-1) , group Cc which received Cuminum cyminum at dose of 1 mg kg(-1) , treatment group which received copper sulphate (100 mg kg(-1) ) and treated with Cuminum cyminum (1 mg kg(-1) ), and control group which received the same volume of normal saline. Six mice in each group were sacrificed at week 4 and week 6. The results showed that sperm concentration, motility and viability in group Cu were significantly decreased at weeks 4 and 6, and severe degenerative changes were observed in testicular tissues in comparison with the control group. In treatment group, significant improvement in the sperm count, motility and viability, and normal architecture in most seminiferous tubules with organised epithelium was observed compared to the group Cu. The sperm quality parameters in the treatment group approached those of the control group. © 2015 Blackwell Verlag GmbH.

  12. Experimental investigations on the influence of the photocathode laser pulse parameters on the electron bunch quality in an RF-photoelectron source

    Energy Technology Data Exchange (ETDEWEB)

    Haenel, Marc

    2010-07-15

    Free Electron Lasers based on the SASE principle like the European XFEL require electron bunches having peak currents of several kiloamperes as well as very low transverse emittance. While high peak currents can be generated using longitudinal bunch compression techniques, the transverse emittance must have values as low as 1mmmrad already at the source. The development of electron sources fulfilling these demanding specifications is the goal of the Photo Injector Test Facility (PITZ) in DESY, Zeuthen site. The key component of a photoinjector is the electron gun cavity where the electrons bunches are generated and immediately accelerated. The extraction of the electrons is based on the photoelectric effect of the cathode which requires a laser system having special capabilities. In the first part of the thesis, measurements are presented which were performed to investigate whether the laser and the laser transport system fulfill these requirements. The second part of the thesis is dedicated to simulations as well as experimental studies on the impact of the temporal and spatial parameters of the laser pulses on the electron bunch quality. This influence is possible because the response time of the Cs{sub 2}Te photocathode is short compared to the laser pulse duration. Based on these investigations, suggestions for improvements are given and tolerances for the laser pulse properties are defined. (orig.)

  13. Online Power Management with Embedded Offline-Optimized Parameters for a Three-Source Hybrid Powertrain with an Experimental Emulation Application

    Directory of Open Access Journals (Sweden)

    Bedatri Moulik

    2016-06-01

    Full Text Available Real-time power management in the presence of one or more reversible energy storage systems is a current issue with hybrid electric vehicles (HEVs. To evaluate the potentials of rule-based power management, optimization with respect to two conflicting objectives, fuel consumption and state of charge (SoC deviation, is considered in this contribution. A modular structure of power management with decoupled offline and online parts is presented. The online part incorporates look-up tables (LUTs with parameters from the offline optimization part. This permits an inclusion of more LUTs corresponding to different drive patterns. The goal of this contribution is to combine the real-time applicability of rule-based power management and the multi-objective optimization property of genetic algorithms in a single control strategy. Component aging problems are addressed by suitable design. The influence of sizing is investigated. Finally, an experimental setup consisting of components capable of realizing the dynamics of real powertrain components is realized and introduced. A verification/plausibility assessment of modeled dynamics based on the literature is considered. This newly-introduced concept represents a class of power management, which is easy to implement, can tackle different objectives in real time, and adapt itself to unknown driver demands.

  14. Effect of ultrasonic treatment on reduction of Esherichia coli ATCC 25922 and egg quality parameters in experimentally contaminated hens' shell eggs.

    Science.gov (United States)

    Sert, Durmus; Aygun, Ali; Torlak, Emrah; Mercan, Emin

    2013-09-01

    In this study, hen eggs which were experimentally contaminated with Esherichia coli ATCC 25922 were used. Contaminated eggs were washed statically (S5 to S30; 0 kHz) and by ultrasonic waves (U5 to U30; 35 kHz) for given applications of time (5, 15 and 30 min), then the eggs were stored at 22°C for 14 days. Depending on the time of ultrasonic application, a significant increase in egg shell strength (P eggs which were washed by ultrasonic waves. Yolk width values of ultrasonic washed eggs diminished. E. coli was completely removed by 30 min of ultrasonic application. During storage E. coli growth was not detected on the eggs which were washed by ultrasonic waves except the eggs in U5 group (2.04 log CFU eggshell⁻¹) on the first day of storage. Depending on the time of ultrasonic application a significant increase in egg quality parameters (shell strength, albumen height, Haugh units, and yolk height) were observed. The application of ultrasound led to a significant reduction in E. coli numbers on egg shells. © 2013 Society of Chemical Industry.

  15. How carryover has an effect on recovery measures related to the area under the curve: theoretical and experimental investigations using cardiovascular parameters.

    Science.gov (United States)

    Sawada, Yukihiro; Kato, Yuichi

    2011-03-01

    This study examines cardiovascular recovery from mental stress. Investigating the absence or presence of carryover effect, the effect of the final reactivity observed at the end of stressful task on the successive recovery, was the major objective. A recently advocated recovery measure related to the area under the curve, mean recovery rate (MRR), was investigated, comparing with the two relatives of this type, total carryover (TCO) and literally area under the curve (AUC). At the onset, a detailed theoretical formulation of each measure was carried out, starting from its original definition. It was predicted that MRR, but not TCO or AUC, could be free from the carryover effect. Next, 88 male students underwent a 5-min mental arithmetic during which blood pressure and heart rate were measured. Nearly all the theoretical predictions (i.e., 5/6 for the three recovery measures by two cardiovascular parameters) were supported by experimental data. There was only one exception: for heart rate, there was a proportional relationship even for MRR versus the final reactivity. Vagal rebound in the recovery period was conceived as the main contributor of this contradiction. The implications of these results for the understanding of future directions in recovery studies are discussed.

  16. Experimental determination of some equilibrium parameter of Damavand tokamak by magnetic probe measurements for representing a physical model for plasma vertical movement.

    Science.gov (United States)

    Farahani, N Darestani; Davani, F Abbasi

    2015-10-01

    This investigation is about plasma modeling for the control of vertical instabilities in Damavand tokamak. This model is based on online magnetic measurement. The algebraic equation defining the vertical position in this model is based on instantaneous force-balance. Two parameters in this equation, including decay index, n, and lambda, Λ, have been considered as functions of time-varying poloidal field coil currents and plasma current. Then these functions have been used in a code generated for modeling the open loop response of plasma. The main restriction of the suitability analysis of the model is that the experiments always have to be performed in the presence of a control loop for stabilizing vertical position. As a result, open loop response of the system has been identified from closed loop experimental data by nonlinear neural network identification method. The results of comparison of physical model with identified open loop response from closed loop experiments show root mean square error percentage less than 10%. The results are satisfying that the physical model is useful as a Damavand tokamak vertical movement simulator.

  17. Parameters optimization using experimental design for headspace solid phase micro-extraction analysis of short-chain chlorinated paraffins in waters under the European water framework directive.

    Science.gov (United States)

    Gandolfi, F; Malleret, L; Sergent, M; Doumenq, P

    2015-08-07

    The water framework directives (WFD 2000/60/EC and 2013/39/EU) force European countries to monitor the quality of their aquatic environment. Among the priority hazardous substances targeted by the WFD, short chain chlorinated paraffins C10-C13 (SCCPs), still represent an analytical challenge, because few laboratories are nowadays able to analyze them. Moreover, an annual average quality standards as low as 0.4μgL(-1) was set for SCCPs in surface water. Therefore, to test for compliance, the implementation of sensitive and reliable analysis method of SCCPs in water are required. The aim of this work was to address this issue by evaluating automated solid phase micro-extraction (SPME) combined on line with gas chromatography-electron capture negative ionization mass spectrometry (GC/ECNI-MS). Fiber polymer, extraction mode, ionic strength, extraction temperature and time were the most significant thermodynamic and kinetic parameters studied. To determine the suitable factors working ranges, the study of the extraction conditions was first carried out by using a classical one factor-at-a-time approach. Then a mixed level factorial 3×2(3) design was performed, in order to give rise to the most influent parameters and to estimate potential interactions effects between them. The most influent factors, i.e. extraction temperature and duration, were optimized by using a second experimental design, in order to maximize the chromatographic response. At the close of the study, a method involving headspace SPME (HS-SPME) coupled to GC/ECNI-MS is proposed. The optimum extraction conditions were sample temperature 90°C, extraction time 80min, with the PDMS 100μm fiber and desorption at 250°C during 2min. Linear response from 0.2ngmL(-1) to 10ngmL(-1) with r(2)=0.99 and limits of detection and quantification, respectively of 4pgmL(-1) and 120pgmL(-1) in MilliQ water, were achieved. The method proved to be applicable in different types of waters and show key advantages, such

  18. Why relevance theory is relevant for lexicography

    DEFF Research Database (Denmark)

    Bothma, Theo; Tarp, Sven

    2014-01-01

    This article starts by providing a brief summary of relevance theory in information science in relation to the function theory of lexicography, explaining the different types of relevance, viz. objective system relevance and the subjective types of relevance, i.e. topical, cognitive, situational...... that is very important for lexicography as well as for information science, viz. functional relevance. Since all lexicographic work is ultimately aimed at satisfying users’ information needs, the article then discusses why the lexicographer should take note of all these types of relevance when planning a new...... dictionary project, identifying new tasks and responsibilities of the modern lexicographer. The article furthermore discusses how relevance theory impacts on teaching dictionary culture and reference skills. By integrating insights from lexicography and information science, the article contributes to new...

  19. Hemodynamic parameters and neurogenic pulmonary edema following spinal cord injury: an experimental model Parâmetros hemodinâmicos e edema pulmonar neurogênico após traumatismo raquimedular: modelo experimental

    Directory of Open Access Journals (Sweden)

    Manoel Baldoino Leal Filho

    2005-12-01

    Full Text Available Neurogenic pulmonary edema is a serious and always life-threatening complication following several lesions of the central nervous system. We report an experiment with 58 Wistar-Hanover adult male rats. Two groups were formed: control (n=4 and experimental (n=54. The experimental group sustained acute midthoracic spinal cord injury by Fogarty’s balloon-compression technique containing 20µL of saline for 5, 15, 30 or 60 seconds. The rats were anesthetized by intraperitoneal (i.p. sodium pentobarbital (s.p. 60 mg/Kg. The quantitative neurological outcome was presented at 4, 24 and 48 hours from compression to characterize the injury graduation in different groups. Poor outcome occurred with 60 seconds of compression. Six animals died suddenly with pulmonary edema. Using the procedure to investigate the pulmonary edema during 60 seconds of compression, followed by decompression and time-course of 60 seconds, 20 rats were randomly asigned to one of the following groups: control (1, n=4, anesthetized by i.p. s.p., 60 mg/Kg but without compression and experimental (2, n=7, anesthetized by i.p. xylazine 10 mg/Kg and ketamine 75 mg/Kg and (3, n=9, anesthetized by i.p. s.p., 60 mg/Kg. The pulmonary index (100 x wet lung weight / body weight was 0.395 ± 0.018 in control group, rose to 0.499 ± 0.060 in group 2, and was 0.639 ± 0.14 in group 3. Histologic examination of the spinal cord showed parenchymal ruptures and acute hemorrhage. Comparison of the pulmonary index with morphometric evaluation of edema fluid-filled alveoli by light microscopy showed that relevant intra-alveolar edema occurred only for index values above 0.55. The results suggest that the pulmonary edema induced by spinal compression is of neurogenic nature and that the type of anesthesia used might be important for the genesis of lung edema.Edema pulmonar neurogênico é complicação séria e aumenta o risco de vida em pacientes com várias lesões do sistema nervoso central

  20. An experimental palladium-103 seed (OptiSeedexp) in a biocompatible polymer without a gold marker: Characterization of dosimetric parameters including the interseed effect

    International Nuclear Information System (INIS)

    Abboud, F.; Scalliet, P.; Vynckier, S.

    2008-01-01

    to obtain relevant dosimetric data as required by TG-43U1 recommendations. Comparison of the results with previous studies of OptiSeed 103 [Phys. Med. Biol. 50, 1493-1504 (2005)]; [Appl. Radiat. Isot. 63, 311-321 (2005)], and of InterSource 103 [Appl. Radiat. Isot. 57, 805-811 (2002)] showed very good agreement for the dose rate constant and for the radial dose function. With respect to the anisotropy function, the relative dose (anisotropy value relative to 90 degree sign ) from the polymer seed at a distance of 3 cm was close to unity (105%) at 0 degree sign , whereas the relative values for the OptiSeed 103 with a gold marker and the titanium-encapsulated InterSource 103 seed decreased to 70% and 40%, respectively. The interseed effect from one seed was negligible and in the order of calculation uncertainty, making calculation of the dose rate distribution of the studied seeds, according to TG43U1 recommendations, more accurate and closer to reality. This feasibility study shows that due to the low energy of palladium-103, the negligible interseed effect and the reduced artifacts in postimplant medical imaging, this experimental plastic seed would be a good source for breast brachytherapy. This feasibility study was carried out in collaboration with IBt and will be continued with a study of its visibility in different tissues.

  1. Deep learning relevance

    DEFF Research Database (Denmark)

    Lioma, Christina; Larsen, Birger; Petersen, Casper

    2016-01-01

    train a Recurrent Neural Network (RNN) on existing relevant information to that query. We then use the RNN to "deep learn" a single, synthetic, and we assume, relevant document for that query. We design a crowdsourcing experiment to assess how relevant the "deep learned" document is, compared...... to existing relevant documents. Users are shown a query and four wordclouds (of three existing relevant documents and our deep learned synthetic document). The synthetic document is ranked on average most relevant of all....

  2. Generating three-parameter sensor

    Directory of Open Access Journals (Sweden)

    Filinyuk M. A.

    2014-08-01

    Full Text Available Generating sensors provide the possibility of getting remote information and its easy conversion into digital form. Typically, these are one-parameter sensors formed by combination of a primary transmitter (PT and a sine wave generator. Two-parameter sensors are not widely used as their implementation causes a problem with ambiguity output when measuring the PT. Nevertheless, the problem of creating miniature, thrifty multi-parameter RF sensors for different branches of science and industry remains relevant. Considering ways of designing RF sensors, we study the possibility of constructing a three-parameter microwave radio frequency range sensor, which is based on a two-stage three-parameter generalized immitance convertor (GIC. Resistive, inductive and capacitive PT are used as sensing elements. A mathematical model of the sensor, which describes the relation of the sensor parameters to the parameters of GIC and PT was developed. The basic parameters of the sensor, its transfer function and sensitivity were studied. It is shown that the maximum value of the power generated signal will be observed at a frequency of 175 MHz, and the frequency ranges depending on the parameters of the PT will be different. Research results and adequacy of the mathematical model were verified by the experiment. Error of the calculated dependences of the lasing frequency on PT parameters change, compared with the experimental data does not exceed 2 %. The relative sensitivity of the sensor based on two-stage GIC showed that for the resistive channel it is about 1.88, for the capacitive channel –1,54 and for the inductive channel –11,5. Thus, it becomes possible to increase the sensor sensitivity compared with the sensitivity of the PT almost 1,2—2 times, and by using the two stage GIC a multifunctional sensor is provided.

  3. Discovering Hidden Controlling Parameters using Data Analytics and Dimensional Analysis

    Science.gov (United States)

    Del Rosario, Zachary; Lee, Minyong; Iaccarino, Gianluca

    2017-11-01

    Dimensional Analysis is a powerful tool, one which takes a priori information and produces important simplifications. However, if this a priori information - the list of relevant parameters - is missing a relevant quantity, then the conclusions from Dimensional Analysis will be incorrect. In this work, we present novel conclusions in Dimensional Analysis, which provide a means to detect this failure mode of missing or hidden parameters. These results are based on a restated form of the Buckingham Pi theorem that reveals a ridge function structure underlying all dimensionless physical laws. We leverage this structure by constructing a hypothesis test based on sufficient dimension reduction, allowing for an experimental data-driven detection of hidden parameters. Both theory and examples will be presented, using classical turbulent pipe flow as the working example. Keywords: experimental techniques, dimensional analysis, lurking variables, hidden parameters, buckingham pi, data analysis. First author supported by the NSF GRFP under Grant Number DGE-114747.

  4. Parâmetros operacionais no processamento de zeólitas desativadas por fusão com KHSO4 Experimental parameters for spent zeolites processing via fusion with KHSO4

    Directory of Open Access Journals (Sweden)

    Luciano Aragão de Mendonça

    2007-04-01

    Full Text Available This work presents a study on the determination of the optimal experimental conditions for processing spent commercial zeolites in order to recover lanthanide elements and eventually other elements. The process is based on the fusion of the sample with potassium hydrogenosulfate (KHSO4. Three experimental parameters were studied: temperature, reaction time and catalyst/flux mass ratio. After fusion the solid was dissolved in water and the amount of insoluble matter was used to determine the efficiency of the process. The optimized experimental parameters depend on the composition of the sample processed. Under such conditions the insoluble residue corresponds to SiO2. Lanthanide elements and aluminum present in solution were isolated by conventional precipitation techniques; the yields were at least 75 wt%. The final generated wastes correspond to neutral colorless solutions containing alkali chlorides/sulfates and solids that can be disposed of in industrial dumps.

  5. Hydrogen isotopes transport parameters in fusion reactor materials

    International Nuclear Information System (INIS)

    Serra, E.; Ogorodnikova, O.V.

    1998-01-01

    This work presents a review of hydrogen isotopes-materials interactions in various materials of interest for fusion reactors. The relevant parameters cover mainly diffusivity, solubility, trap concentration and energy difference between trap and solution sites. The list of materials includes the martensitic steels (MANET, Batman and F82H-mod.), beryllium, aluminium, beryllium oxide, aluminium oxide, copper, tungsten and molybdenum. Some experimental work on the parameters that describe the surface effects is also mentioned. (orig.)

  6. A dynamic transfer model by means of experimental data collected after Chernobyl accident, for evaluating some parameters concerning the radioactive migration in the environment

    International Nuclear Information System (INIS)

    Monte, L.

    1988-01-01

    Using the environment contamination data collected during the Chernobyl accident, some important parameters for assessing the environmental transfer of 131 I and 137 Cs in dynamical conditions are determined

  7. Investigation of optimized experimental parameters including laser wavelength for boron measurement in photovoltaic grade silicon using laser-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Darwiche, S.; Benmansour, M.; Eliezer, N.; Morvan, D.

    2010-01-01

    The quantification of boron and other impurities in photovoltaic grade silicon was investigated using the LIBS technique with attention to the laser wavelength employed, temporal parameters, and the nature of the ambient gas. The laser wavelength was found to have a moderate effect on the performance of the process, while the type of purge gas and temporal parameters had a strong effect on the signal-to-background ratio (SBR) of the boron spectral emission, which was used to determine the boron concentration in silicon. The three parameters are not independent, meaning that for each different purge gas, different optimal temporal parameters are observed. Electron density was also calculated from Stark broadening of the 390.5 nm silicon emission line in order to better understand the different performances observed when using different gases and gating parameters. Calibration curves were made for boron measurement in silicon using certified standards with different purge gases while using the temporal parameters which had been optimized for that gas. By comparing the calibration curves, it was determined that argon is superior to helium or air for use as the analysis chamber purge gas with an UV laser.

  8. Development of an Agent-Based Model (ABM) to Simulate the Immune System and Integration of a Regression Method to Estimate the Key ABM Parameters by Fitting the Experimental Data

    Science.gov (United States)

    Tong, Xuming; Chen, Jinghang; Miao, Hongyu; Li, Tingting; Zhang, Le

    2015-01-01

    Agent-based models (ABM) and differential equations (DE) are two commonly used methods for immune system simulation. However, it is difficult for ABM to estimate key parameters of the model by incorporating experimental data, whereas the differential equation model is incapable of describing the complicated immune system in detail. To overcome these problems, we developed an integrated ABM regression model (IABMR). It can combine the advantages of ABM and DE by employing ABM to mimic the multi-scale immune system with various phenotypes and types of cells as well as using the input and output of ABM to build up the Loess regression for key parameter estimation. Next, we employed the greedy algorithm to estimate the key parameters of the ABM with respect to the same experimental data set and used ABM to describe a 3D immune system similar to previous studies that employed the DE model. These results indicate that IABMR not only has the potential to simulate the immune system at various scales, phenotypes and cell types, but can also accurately infer the key parameters like DE model. Therefore, this study innovatively developed a complex system development mechanism that could simulate the complicated immune system in detail like ABM and validate the reliability and efficiency of model like DE by fitting the experimental data. PMID:26535589

  9. Experimental determination of the electronic properties of application-relevant interfaces of organic semiconductors by means of photoelectron spectroscopy; Experimentelle Bestimmung der elektronischen Eigenschaften anwendungsrelevanter Grenzflaechen organischer Halbleiter mittels Photoelektronenspektroskopie

    Energy Technology Data Exchange (ETDEWEB)

    Grobosch, Mandy

    2009-07-01

    This thesis under the titel Experimental Determination of the Electronic Properties of Application-relevant Interfaces of Organic Semiconductors by means of Photoelectron Spectroscopy was drawn up at the Leibniz Institute for Solid-State and Materials Research (IFW) Dresden at the Institute for Solid-State Research (IFF) under the maintenance of Prof. Dr. B. Buechner. To the scientific study hereby came two types of application-relevant interfaces. On the one hand the influence of the electrode preparation under normal conditions by means of ex-situ purification procedures in comparison to in-situ prepared contacts on the electronic behaviour of the organic semiconductor sexithiophene on interfaces to metallic substrates was studied. As substrate materials hereby the metals silver, palladium, gold, and platinum came to application. In a second study the interfaces of the organic semiconductors sexithiophene and copper(II)-phthalocyanine in contact to thin films of the transition-metal oxide La{sub 0.7}Sr{sub 0.3}MnO{sub 3} were studied. Also here a comparing study for ex-situ and in-situ purificated La{sub 0.7}Sr{sub 0.3}MnO{sub 3} contacts was performed. The films applied for this were fabricated in the IWF Dresden at the Institute for Metallic Materials (IMW). Also in the framework of these studies the influence of oxygen on the electronic and chemical behaviour on the interfaces held the spotlight. [German] Diese Dissertation unter dem Titel Experimentelle Bestimmung der elektronischen Eigenschaften anwendungsrelevanter Grenzflaechen organischer Halbleiter mittels Photoelektronenspektroskopie wurde am Leibniz Institut fuer Festkoerper- und Werkstoffforschung (IFW) Dresden am Institut fuer Festkoerperforschung (IFF) unter der Betreuung von Prof. Dr. B. Buechner angefertigt. Zur wissenschaftlichen Untersuchung kamen hierbei zwei Typen anwendungsrelevanter Grenzflaechen. Zum einem wurde der Einfluss einer Elektrodenpraeparation unter Normalbedingungen mittels ex

  10. Experimental parameter identification of a multi-scale musculoskeletal model controlled by electrical stimulation: application to patients with spinal cord injury.

    Science.gov (United States)

    Benoussaad, Mourad; Poignet, Philippe; Hayashibe, Mitsuhiro; Azevedo-Coste, Christine; Fattal, Charles; Guiraud, David

    2013-06-01

    We investigated the parameter identification of a multi-scale physiological model of skeletal muscle, based on Huxley's formulation. We focused particularly on the knee joint controlled by quadriceps muscles under electrical stimulation (ES) in subjects with a complete spinal cord injury. A noninvasive and in vivo identification protocol was thus applied through surface stimulation in nine subjects and through neural stimulation in one ES-implanted subject. The identification protocol included initial identification steps, which are adaptations of existing identification techniques to estimate most of the parameters of our model. Then we applied an original and safer identification protocol in dynamic conditions, which required resolution of a nonlinear programming (NLP) problem to identify the serial element stiffness of quadriceps. Each identification step and cross validation of the estimated model in dynamic condition were evaluated through a quadratic error criterion. The results highlighted good accuracy, the efficiency of the identification protocol and the ability of the estimated model to predict the subject-specific behavior of the musculoskeletal system. From the comparison of parameter values between subjects, we discussed and explored the inter-subject variability of parameters in order to select parameters that have to be identified in each patient.

  11. Experimental investigation on the effect of intake air temperature and air-fuel ratio on cycle-to-cycle variations of HCCI combustion and performance parameters

    Energy Technology Data Exchange (ETDEWEB)

    Maurya, Rakesh Kumar; Agarwal, Avinash Kumar [Engine Research Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016 (India)

    2011-04-15

    Combustion in HCCI engines is a controlled auto ignition of well-mixed fuel, air and residual gas. Since onset of HCCI combustion depends on the auto ignition of fuel/air mixture, there is no direct control on the start of combustion process. Therefore, HCCI combustion becomes unstable rather easily, especially at lower and higher engine loads. In this study, cycle-to-cycle variations of a HCCI combustion engine fuelled with ethanol were investigated on a modified two-cylinder engine. Port injection technique is used for preparing homogeneous charge for HCCI combustion. The experiments were conducted at varying intake air temperatures and air-fuel ratios at constant engine speed of 1500 rpm and P-{theta} diagram of 100 consecutive combustion cycles for each test conditions at steady state operation were recorded. Consequently, cycle-to-cycle variations of the main combustion parameters and performance parameters were analyzed. To evaluate the cycle-to-cycle variations of HCCI combustion parameters, coefficient of variation (COV) of every parameter were calculated for every engine operating condition. The critical optimum parameters that can be used to define HCCI operating ranges are 'maximum rate of pressure rise' and 'COV of indicated mean effective pressure (IMEP)'. (author)

  12. An experimental analysis of process parameters to manufacture micro-channels in AISI H13 tempered steel by laser micro-milling

    Science.gov (United States)

    Teixidor, D.; Ferrer, I.; Ciurana, J.

    2012-04-01

    This paper reports the characterization of laser machining (milling) process to manufacture micro-channels in order to understand the incidence of process parameters on the final features. Selection of process operational parameters is highly critical for successful laser micromachining. A set of designed experiments is carried out in a pulsed Nd:YAG laser system using AISI H13 hardened tool steel as work material. Several micro-channels have been manufactured as micro-mold cavities varying parameters such as scanning speed (SS), pulse intensity (PI) and pulse frequency (PF). Results are obtained by evaluating the dimensions and the surface finish of the micro-channel. The dimensions and shape of the micro-channels produced with laser-micro-milling process exhibit variations. In general the use of low scanning speeds increases the quality of the feature in both surface finishing and dimensional.

  13. Optimal Design of Shock Tube Experiments for Parameter Inference

    KAUST Repository

    Bisetti, Fabrizio

    2014-01-06

    We develop a Bayesian framework for the optimal experimental design of the shock tube experiments which are being carried out at the KAUST Clean Combustion Research Center. The unknown parameters are the pre-exponential parameters and the activation energies in the reaction rate expressions. The control parameters are the initial mixture composition and the temperature. The approach is based on first building a polynomial based surrogate model for the observables relevant to the shock tube experiments. Based on these surrogates, a novel MAP based approach is used to estimate the expected information gain in the proposed experiments, and to select the best experimental set-ups yielding the optimal expected information gains. The validity of the approach is tested using synthetic data generated by sampling the PC surrogate. We finally outline a methodology for validation using actual laboratory experiments, and extending experimental design methodology to the cases where the control parameters are noisy.

  14. Experimental study of a model and parameters calculating annual mean atmospheric dispersion factor for a nuclear power plant to be build in coastal site

    International Nuclear Information System (INIS)

    Hu Erbang; Chen Jiayi; Zhang Maoshuan; Gao Zhanrong; Yao Rentai; Jia Peirong; Qiao Qingdang

    1999-01-01

    The author tries to develop a new model calculating annual mean atmospheric dispersion factor for a nuclear power plant to be build in coastal site based on field experiments. This model considers not only the difference between shore ward and off-shore but also the comprehensive effect of following factors: mixed layer and thermal internal boundary layer, mixing release and variation of diffusion parameters due to the distance from coast and so on. The various parameters needed in the model are obtained from the field atmospheric experiments done on the NPP site during 1995∼1996. There dimension joint frequency is got from wind and temperature measurements at 4 heights of a tower of 100 m; diffusion parameters shore ward and off-shore from turbulent measurement and wind tunnel simulation test; the parameters relative to sea and land breeze and thermal internal boundary layer are obtained from tests with low altitude radiosonde and lost balloon at 3 sites during two periods of Summer and Winter. Finally a comparison of the results given by this model and commonly used model provided by relative guides is done. The comparison shows that about 1 times under estimation is found for the maximum of annual mean atmospheric dispersion factor in common model because the effect from thermal internal boundary layer and other factors are neglected

  15. Graft copolymerization of acrylic acid to cassava starch-Evaluation of the influences of process parameters by an experimental design method

    NARCIS (Netherlands)

    Witono, J. R.; Noordergraaf, I. W.; Heeres, H. J.; Janssen, L. P. B. M.

    2012-01-01

    The graft copolymerization of cassava starch with acrylic acid was investigated using a free radical initiator system (Fe2+/H2O2 redox system) in water. A comprehensive understanding of the important variables and their interaction has been obtained by applying an experimental design method. In this

  16. Oxidative and proteolysis-related parameters of skeletal muscle from hamsters with experimental pulmonary emphysema: a comparison between papain and elastase induction.

    Science.gov (United States)

    Brunnquell, Cláudia R; Vieira, Nichelle A; Sábio, Laís R; Sczepanski, Felipe; Cecchini, Alessandra L; Cecchini, Rubens; Guarnier, Flávia A

    2015-06-01

    The objective of this study was to investigate whether emphysema induced by elastase or papain triggers the same effects on skeletal muscle, related to oxidative stress and proteolysis, in hamsters. For this purpose, we evaluated pulmonary lesions, body weight, muscle loss, oxidative stress (thiobarbituric acid-reactive substances, total and oxidized glutathiones, chemiluminescence stimulated by tert-butyl hydroperoxide and carbonyl proteins), chymotrypsin-like and calpain-like proteolytic activities and muscle fibre cross-sectional area in the gastrocnemius muscles of emphysemic hamsters. Two groups of animals received different intratracheal inductions of experimental emphysema: by 40 mg/ml papain (EP) or 5.2 IU/100 g animal (EE) elastase (n = 10 animals/group). The control group received intratracheal instillation of 300 μl sterile NaCl 0.9%. Compared with the control group, the EP group had reduced muscle weight (18.34%) and the EE group had increased muscle weight (8.37%). Additionally, tert-butyl hydroperoxide-initiated chemiluminescence, carbonylated proteins and chymotrypsin-like proteolytic activity were all elevated in the EP group compared to the CS group, while total glutathione was decreased compared to the EE group. The EE group showed more fibres with increased cross-sectional areas and increased calpain-like activity. Together, these data show that elastase and papain, when used to induce experimental models of emphysema, lead to different speeds and types of adaptation. These findings provide more information on choosing a suitable experimental model for studying skeletal muscle adaptations in emphysema. © 2015 The Authors. International Journal of Experimental Pathology © 2015 International Journal of Experimental Pathology.

  17. A new method for the continuous production of single dosed controlled release matrix systems based on hot-melt extruded starch: analysis of relevant process parameters and implementation of an in-process control.

    Science.gov (United States)

    Kipping, Thomas; Rein, Hubert

    2013-05-01

    In the present study, we evaluated a novel processing technique for the continuous production of hot-melt extruded controlled release matrix systems. A cutting technique derived from plastics industry, where it is widely used for cutting of cables and wires was adapted into the production line. Extruded strands were shaped by a rotary fly cutter. Special focus is laid on the development of a process analytical technology by evaluating signals obtained from the servo control of the rotary fly cutter. The intention is to provide a better insight into the production process and to offer the ability to detect small variations in process-variables. A co-rotating twin-screw extruder ZSE 27 HP-PH from Leistritz (Nürnberg, Germany) was used to plasticize the starch; critical extrusion parameters were recorded. Still elastic strands were shaped by a rotary fly-cutter type Dynamat 20 from Metzner (Neu-Ulm, Germany). Properties of the final products were analyzed via digital image analysis to point out critical parameters influencing the quality. Important aspects were uniformity of diameter, height, roundness, weight, and variations in the cutting angle. Stability of the products was measured by friability tests and by determining the crushing strength of the final products. Drug loading studies up to 70% were performed to evaluate the capacity of the matrix and to prove the technological feasibility. Changes in viscosities during API addition were analyzed by a Haake Minilab capillary rheometer. X-ray studies were performed to investigate molecular structures of the matrices. External shapes of the products were highly affected by die-swelling of the melt. Reliable reproducibility concerning uniformity of mass could be achieved even for high production rates (>2500cuts/min). Both mechanical strength and die-swelling of the products could be linked to the ratio of amylose to amylopectin. Formulations containing up to 70% of API could still be processed. Viscosity

  18. Molecular modeling and experimental studies on structure and NMR parameters of 9-benzyl-3,6-diiodo-9H-carbazole

    DEFF Research Database (Denmark)

    Radula-Janik, Klaudia; Kupka, Teobald; Ejsmont, Krzysztof

    2015-01-01

    A combined experimental and theoretical study has been performed on 9-benzyl-3,6-diiodo-9H-carbazole. Experimental X-ray (100.0 K) and room-temperature 13C NMR studies were supported by advanced density functional theory (DFT) calculations. The non relativistic structure optimization was performed...... and the 13C nuclear magnetic shieldings were predicted at the relativistic level of theory using the Zeroth Order Regular Approximation (ZORA). The changes in the benzene and pyrrole rings compared to the unsubstituted carbazole or the parent molecules were discussed in terms of aromaticity changes using...... the harmonic oscillator model of aromaticity (HOMA) and the nucleus independent chemical shift (NICS) indexes. Theoretical relativistic calculations of chemical shifts of carbons C3 and C6, directly bonded to iodine atoms, produced a reasonable agreement with experiment (initial deviation from experiment of 41...

  19. Experimental research of the influence of the strength of ore samples on the parameters of an electromagnetic signal during acoustic excitation in the process of uniaxial compression

    Science.gov (United States)

    Yavorovich, L. V.; Bespal`ko, A. A.; Fedotov, P. I.

    2018-01-01

    Parameters of electromagnetic responses (EMRe) generated during uniaxial compression of rock samples under excitation by deterministic acoustic pulses are presented and discussed. Such physical modeling in the laboratory allows to reveal the main regularities of electromagnetic signals (EMS) generation in rock massive. The influence of the samples mechanical properties on the parameters of the EMRe excited by an acoustic signal in the process of uniaxial compression is considered. It has been established that sulfides and quartz in the rocks of the Tashtagol iron ore deposit (Western Siberia, Russia) contribute to the conversion of mechanical energy into the energy of the electromagnetic field, which is expressed in an increase in the EMS amplitude. The decrease in the EMS amplitude when the stress-strain state of the sample changes during the uniaxial compression is observed when the amount of conductive magnetite contained in the rock is increased. The obtained results are important for the physical substantiation of testing methods and monitoring of changes in the stress-strain state of the rock massive by the parameters of electromagnetic signals and the characteristics of electromagnetic emission.

  20. Identification and determination of trapping parameters as key site parameters for CO2 storage for the active CO2 storage site in Ketzin (Germany) - Comparison of different experimental approaches and analysis of field data

    Science.gov (United States)

    Zemke, Kornelia; Liebscher, Axel

    2015-04-01

    Petrophysical properties like porosity and permeability are key parameters for a safe long-term storage of CO2 but also for the injection operation itself. The accurate quantification of residual trapping is difficult, but very important for both storage containment security and storage capacity; it is also an important parameter for dynamic simulation. The German CO2 pilot storage in Ketzin is a Triassic saline aquifer with initial conditions of the target sandstone horizon of 33.5 ° C/6.1 MPa at 630 m. One injection and two observation wells were drilled in 2007 and nearly 200 m of core material was recovered for site characterization. From June 2008 to September 2013, slightly more than 67 kt food-grade CO2 has been injected and continuously monitored. A fourth observation well has been drilled after 61 kt injected CO2 in summer 2012 at only 25 m distance to the injection well and new core material was recovered that allow study CO2 induced changes in petrophysical properties. The observed only minor differences between pre-injection and post-injection petrophysical parameters of the heterogeneous formation have no severe consequences on reservoir and cap rock integrity or on the injection behavior. Residual brine saturation for the Ketzin reservoir core material was estimated by different methods. Brine-CO2 flooding experiments for two reservoir samples resulted in 36% and 55% residual brine saturation (Kiessling, 2011). Centrifuge capillary pressure measurements (pc = 0.22 MPa) yielded the smallest residual brine saturation values with ~20% for the lower part of the reservoir sandstone and ~28% for the upper part (Fleury, 2010). The method by Cerepi (2002), which calculates the residual mercury saturation after pressure release on the imbibition path as trapped porosity and the retracted mercury volume as free porosity, yielded unrealistic low free porosity values of only a few percent, because over 80% of the penetrated mercury remained in the samples after

  1. Assessment of the failure behavior of dangerous goods containers made of high density polyethylene using relevant material parameters; Beurteilung des Versagensverhaltens von Gefahrengutbehaeltern aus Polyethylen hoher Dichte auf Basis relevanter Werkstoffkennwerte

    Energy Technology Data Exchange (ETDEWEB)

    Menrad, Andreas

    2013-09-01

    To obtain approval as dangerous goods packaging, different experimental tests are required to show the eligibility for the transportation of those goods. The data obtained from the material test performed on the pressed plates is not used to get absolute values for the failure time in an internal pressure test or the medium drop height. The goal is to see if there are changes in the behavior because a different HDPE is being used. All the jerrycans and pressed plates were specially made of four different materials to gain knowledge about the material properties. The plates and jerrycans were made of resin from the same batch to prevent variations caused by batch differences. The wall thickness is decisive and, therefore packagings were analyzed using computer tomography and the fringe projection technique. The results were compared to the magnetostatic measurement technique. The deformation under internal pressure was measured by digital image correlation. Deformations in the radial direction and the equivalent strains were determined. These deformations, strains, and their acceleration due to the swelling effect could be reproduced in the finite element analysis by using the temperature in the material model. The resistance against both internal pressure and absorption depend on the density of the material. Conditioning at elevated temperatures causes post crystallization and reduces internal stresses. Differences in the densities of the materials can be determined by using plates manufactured by compression molding. A higher density leads to a better performance under internal pressure. A correlation could be proved between the medium failure drop height (50 % of the packagings fail because of a crack) and the tensile impact strength of notched specimens cut out of the jerrycans side walls and the notched impact strength (NIS) of pressed plates. A higher NIS leads to a higher medium failure drop height. A low resistance against oxidative degradation will reduce

  2. Experimental determination of the atmospheric dispersion parameters at the Karlsruhe Nuclear Research Center for 60 m and 100 m emission heights. Pt. 1

    International Nuclear Information System (INIS)

    Thomas, P.; Dilger, H.; Huebschmann, W.; Schuettelkopf, H.; Vogt, S.; Kernforschungszentrum Karlsruhe G.m.b.H.

    1981-09-01

    Experiments have been carried out at the Karlsruhe Nuclear Research Center in order to investigate the atmospheric diffusion of pollutants. The influence on atmospheric diffusion of topographic conditions specific to the site is to be determined. For this purpose, halogenated hydrocarbons are emitted at 60 m and 100 m height; their local concentration distribution is measured at ground level downwind of the source. Part 1 of the report describes the diffusion experiments performed and presents the measured data in a detailed manner. The data include the coordinates of the sampling positions, the measured concentrations and the relevant meteorological data recorded during the experiments. The stability classes prevailing during the experiments are derived from these data and are indicated. (orig./HP) [de

  3. An assessment of the parameters and experimental data of the continuous water activity monitors operating in the upstream and downstream channels of the Paks nuclear power plant

    International Nuclear Information System (INIS)

    Nagy, Gy.; Feher, I.

    1986-03-01

    A NaI(Tl) scintillator was placed into a measuring vessel of 8 msup(3) volume for monitoring the effluents in the upstream and downstream channels of the Paks nuclear power plant. The effects of radioactivity, meteorological parameters, and the atmospheric pressure on the counting rates, and their daily and monthly average values in both channels were analyzed. The short-term increases of the monitor signals could be attributed to rainy weather. The sup(222)Rn countent of water was also evaluated. (author)

  4. An experimental determination of the parameters describing the K/sup + / to pi /sup +/ pi /sup 0/ pi /sup 0/ decay matrix element

    CERN Document Server

    Braun, H; Erriquez, O; Martyn, H U; Renton, P B; Romano, F; Vilain, P; Waldren, D

    1976-01-01

    The matrix element of the three pion decay mode of the kaon is expressed in terms of Mandelstam variables. An analysis of the Dalitz plot density distribution gives information on the parameters of the expression. From an analysis of the decays of stopping K/sup +/ mesons involving neutral pions in the CERN heavy-liquid bubble chamber filled with a propane ethane mixture, it is concluded that the energy dependence of the decay matrix element is compatible with a linear behaviour. (3 refs).

  5. Synthesis of fiber Bragg grating parameters from experimental reflectivity: a simplex approach and its application to the determination of temperature-dependent properties.

    Science.gov (United States)

    Lhommé, Frederic; Caucheteur, Christophe; Chah, Karima; Blondel, Michel; Mégret, Patrice

    2005-02-01

    A simple, accurate, and fast method to synthesize the physical parameters of a fiber Bragg grating numerically from its reflectivity is proposed and demonstrated. Our program uses the transfer matrix method and is based on a Nelder-Mead simplex optimization algorithm. It can be applied to both uniform and nonuniform (apodized and chirped) fiber Bragg gratings. The method is then used to synthesize a uniform Bragg grating from its reflectivity taken at different temperatures. It gives a good estimate of the thermal expansion coefficient and the thermo-optic coefficient of the fiber.

  6. Study of the experimental parameters associated to the determination of residual macro stresses in stainless steel tubes, through x-ray diffraction method

    International Nuclear Information System (INIS)

    Guimaraes, L.R.

    1990-01-01

    The basic principles related to the determination of residual macro stresses by X-rays diffractometry are present, whereas different techniques associated with the respective experimental errors are discussed. The residual stresses in two 304 L stainless steel tubes were measured using three models of diffractometers, Rigaku SG-8, Jeol JDX-11PA and Rigaku Strainflex. The measured values of stresses as well as the reproducibilities are examined. The suitability of peak location method, by fitting three data points to the parabolic function, is discussed through values of position and intensity obtained by two of the above diffractometers. (author)

  7. Study of the experimental parameters associated to the determination of residual macro stresses in stainless steel tubes through x-rays diffraction method

    International Nuclear Information System (INIS)

    Guimaraes, L.R.

    1990-01-01

    The basic principles related to the determination of residual macro stresses by X-rays diffractometry are present, whereas different techniques associated with the respective experimental errors are discussed. The residual stresses in two 304 L stainless steel tubes were measured using three models of diffractometers, Rigaku SG-8, Jeol JDX-11PA and Rigaku Strainflex. The measured values of stresses as well as the reproducibilities are examined. The suitability of peak location method, by fitting three data points to the parabolic function, is discussed through values of position and intensity obtained by two of the above diffractometers. (author)

  8. Time course of the rise in UV fluorescence intensity following irradiation and experimental conditions for the determination of this parameter in vital Ehrlich-ascitic tumour cells

    International Nuclear Information System (INIS)

    Merkle, K.

    1977-01-01

    The use of the impulse cytophotometric method of measurement in the UV region of the spectrum has allowed to determine the change of primary fluorescence intensity on vital unstained cells without the influence of UV exposure or other factors affecting the measuring result in an uncontrollable way. The studies on the influence of storage time and -temperature have shown that a storage time of up to 25 min at 20 0 C has no effect on the fluorescence intensity of Ehrlich ascites cells. On day 11 after inoculation the fluorescence level is about 20% higher than on day 8, but is much better reproducible at the latter date. After 600 rads gamma irradiation applied on the 6th day, this parameter starts oscillating around normal values and is stabilized within 20 hrs after irradiation; these values remain constant in the next 40 hrs. Even after exposure to 100, 200 and 300 rads gamma radiation a constant UV fluorescence intensity is registered in this time interval. Measurements of this parameter in the phase of relative constancy allow a clear-cut interpretation of the results of further radiobiological investigations. (author)

  9. Experimental estimation and optimization of process parameters under minimum quantity lubrication and dry turning of AISI-4340 with different carbide inserts

    Energy Technology Data Exchange (ETDEWEB)

    Saini, Akash; Setia, Sunil [Lovely Professional University, Phagwara (India); Dhiman, Suresh; Sharma, Rajesh [National Institute of Technology, Hamirpur (India)

    2014-06-15

    An experimental study has been performed on AISI 4340 steel in this paper. The influence of approach angle, feed rate, cutting speed and depth of cut has been on cutting forces and tool tip temperature has been experimentally investigated. Before conducting experiments on the AISI 4340 steel work-piece, the chemical composition test, microstructure test were performed and hardness of the work-piece was improved by heat treatment. A total of 64 experiments each by two different coated carbide inserts (PVD and CVD-coated) were conducted on AISI-4340 steel under different environmental conditions (dry and MQL machining). During the experiments, approach angle, cutting speed, feed rate are varied to four levels and the depth of cut is kept constant to investigate the effect of the same on the three cutting forces component and the temperature variations on the tool-tip. It is observed that the main cutting force was largest among the three cutting force components in case of AISI 4340 steel turning and MQL machining show beneficial effects compared to dry machining.

  10. Justification for parameters of a dynamic stabilizer of the experimental stand mobile unit in studying of active rotational working tools of tiller machines

    Directory of Open Access Journals (Sweden)

    Vladimir F. Kupryashkin

    2017-03-01

    Full Text Available Introduction: The article deals with design options and technological modes of the dynamic stabilizer of the experimental stand mobile unit for studying tillage machine active rotating work tools. Based on theoretical and experimental studies, the possibility the movable module instability was discovered. This negatively affects on implementing the experiment program trough the especific method. The need in engineering solutions for the defect correction is shown. In addition, the authors consider the structural features and characteristics of the used devices for providing the stabilization of the movable module in the study of active rotating work tools of tillage machines. An electromagnetic brake dynamic stabilizer in the structure of the existing rolling module was proposed as an engineering device. Materials and Methods: A theoretical study of rolling module stability, based on synthesis of basic regulations and laws of mechanics related to active rotating work tools was conducted. As a result of the theoretical research, a design scheme of movable module loading was created. This scheme includes the design features and structural power factors. Results: A database representing the settings of power specification in the motion stability determining the mobile unit was created. Further use of the database values allow supporting the most optimal location of the electromagnetic brake with its design options. Discussion and Conclusions: The research of the electromagnetic brake in a mobile unit promoted stabilizing the unit movement, increased the frequency of its use and provided data that are more precise during experiments.

  11. Experimental estimation and optimization of process parameters under minimum quantity lubrication and dry turning of AISI-4340 with different carbide inserts

    International Nuclear Information System (INIS)

    Saini, Akash; Setia, Sunil; Dhiman, Suresh; Sharma, Rajesh

    2014-01-01

    An experimental study has been performed on AISI 4340 steel in this paper. The influence of approach angle, feed rate, cutting speed and depth of cut has been on cutting forces and tool tip temperature has been experimentally investigated. Before conducting experiments on the AISI 4340 steel work-piece, the chemical composition test, microstructure test were performed and hardness of the work-piece was improved by heat treatment. A total of 64 experiments each by two different coated carbide inserts (PVD and CVD-coated) were conducted on AISI-4340 steel under different environmental conditions (dry and MQL machining). During the experiments, approach angle, cutting speed, feed rate are varied to four levels and the depth of cut is kept constant to investigate the effect of the same on the three cutting forces component and the temperature variations on the tool-tip. It is observed that the main cutting force was largest among the three cutting force components in case of AISI 4340 steel turning and MQL machining show beneficial effects compared to dry machining.

  12. Making Deferred Taxes Relevant

    NARCIS (Netherlands)

    Brouwer, Arjan; Naarding, Ewout

    2018-01-01

    We analyse the conceptual problems in current accounting for deferred taxes and provide solutions derived from the literature in order to make International Financial Reporting Standards (IFRS) deferred tax numbers value-relevant. In our view, the empirical results concerning the value relevance of

  13. Parsimonious relevance models

    NARCIS (Netherlands)

    Meij, E.; Weerkamp, W.; Balog, K.; de Rijke, M.; Myang, S.-H.; Oard, D.W.; Sebastiani, F.; Chua, T.-S.; Leong, M.-K.

    2008-01-01

    We describe a method for applying parsimonious language models to re-estimate the term probabilities assigned by relevance models. We apply our method to six topic sets from test collections in five different genres. Our parsimonious relevance models (i) improve retrieval effectiveness in terms of

  14. Study of castor oil polyurethane - poly(methyl methacrylate semi-interpenetrating polymer network (SIPN reaction parameters using a 2³ factorial experimental design

    Directory of Open Access Journals (Sweden)

    Fernanda Oliveira Vieira da Cunha

    2004-12-01

    Full Text Available In this work was employed a 2³ factorial experiment design to evaluate the castor oil polyurethane-poly(methyl methacrylate semi-IPN synthesis. The reaction parameters used as independent variables were NCO/OH molar ratio, polyurethane polymerization time and methyl methacrylate (MMA content. The semi-IPNs were cured over 28 h using two thermal treatments. The polymers were characterized by infrared and Raman spectroscopy, thermal analysis and swelling profiles in n-hexane. The glass transition temperature (Tg and the swelling were more affect by the NCO/OH molar ratio variation. The semi-IPNs showed Tg from - 27 to - 6 °C and the swelling range was from 3 to 22%, according to the crosslink density. The IPN mechanical properties were dependent on the cure temperature and MMA content in it. Lower elastic modulus values were observed in IPNs cured at room temperature.

  15. Changes in various metabolic parameters in blood and milk during experimental Escherichia coli mastitis for primiparous Holstein dairy cows during early lactation

    DEFF Research Database (Denmark)

    Moyes, Kasey M; Larsen, Torben; Sørensen, Peter

    2014-01-01

    BackgroundThe objective of this study was to characterize the changes in various metabolic parameters in blood and milk during IMI challenge with Escherichia coli (E. coli) for dairy cows during early lactation. Thirty, healthy primiparous Holstein cows were infused (h = 0) with ~20-40 cfu of live...... the effect of IMI challenge on metabolic responses of cows during early lactation.ResultsBy 12 h, E. coli was recovered from challenged quarters and shedding continued through 72 h. Rectal temperature peaked by 12 h post-challenge and returned to pre-challenge values by 36 h post-IMI challenge. Daily feed...... intake and milk yield decreased (P mastitis challenge. Plasma BHBA decreased (12 h; P

  16. Effects of iridoid-anthocyanin extract of Cornus mas L. on hematological parameters, population and proliferation of lymphocytes during experimental infection of mice with Trichinella spiralis.

    Science.gov (United States)

    Piekarska, Jolanta; Szczypka, Marianna; Kucharska, Alicja Z; Gorczykowski, Michał

    2018-05-01

    The influence of iridoid-anthocyanin aqueous extract of cornelian cherry fruits (CM) on hematological parameters, lymphocyte subsets and proliferation during Trichinella spiralis infection in mice was investigated. CM (100 mg/kg) was administered orally to T. spiralis-infected mice six times within a period encompassing three days prior to the infection and three days after the infection (dai). CM increased the percentage of CD3 + , CD4 + cells and CD4 + /CD8 + ratio and decreased total count of CD8 + and CD19 + splenocytes (5 th dai). An increase in total count of CD4 + , CD3 + , CD19 + splenocytes was observed (21 st dai). CM elevated the percentage of CD4 + cells (7 th dai) and CD4 + /CD8 + ratio (21 st dai) in MLN. CM increased (14 th dai) and then reduced (21 st dai) the percentage of CD8 + MLN lymphocytes and decreased total count of MLN CD8 + cells (21 st dai) and B cells (14 th dai). An activation of lymphocyte proliferation in spleen and simultaneous decrease in MLN on 5 th dai was observed. An increase in red blood cells parameters (5 th dai) and in leukocyte count (7 th dai) was found. A rise in platelet count was noticed both on 5 th and 7 th dai. Moreover, the number of adult T. spiralis on 5 th dai in mice receiving CM extract was lower than in the control mice. These results suggested that iridoid-anthocyanin aqueous extract of CM stimulated murine immune response during T. spiralis infection. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Study of the experimental parameters for the determination of Ca, Cr, Cu, Fe, Mn and Ni on nuclear grade UO2 by X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Salvador, V.L.R.

    1982-01-01

    An analytical method for the simultaneous determinations of low concentrations of Ca, Cr, Cu, Fe, Mn and Ni on the nuclear grade UO 2 by X-ray fluorescence technique, without the use of chemical treatment, is described. The optimization of the experimental conditions was established on the X-ray fluorescence spectrometer and a low limit of detection (4 - 7 μg/gU) was achieved which satisfies the requirement in the nuclear fuel specification. The samples were prepared in the form of double layer pressed pellets using boric acid as a binding agent. The characteristic first order K sub(α) line intensity of each minor component was measured and the values of its concentrations were deduced using respective standard calibrations curves. The precision, accuracy and acceptability of the method were determined for all elements. The values of the precision are in the range of 2 - 10% and the accuracy are lower than 7%. (Author) [pt

  18. [Influence of cattle cord blood fraction below 5 kD on biochemical parameters of blood in experimental chronic stomach ulcer in rats].

    Science.gov (United States)

    Gulevskiĭ, A K; Abakumova, E S; Moiseeva, N N; Dolgikh, O L

    2008-01-01

    Influence of cattle cord blood fraction (below 5 kD) on lipid peroxidation product content and alkaline phosphatase activity-in peripheral blood was studied on the experimental subchronic stomach ulcer model in rats. It has been shown that the fraction administrations normalize thiobarbituric-active product content and alkaline phosphatase activity in blood, which testifies to decreasing inflammatory reaction in the mucous membrane of the stomach. The fraction administrations accelerate the processes of regeneration of the mucous membrane of the stomach up to complete healing of ulcer defects. Cord blood fraction below 5 kD from cattle possesses antiulcer activity which is analogous to the actovegin activity. It has been shown by gel-penetrating chromatography that the pattern of cord blood fraction low molecular substances is different from the actovegin pattern both qualitatively and quantitatively.

  19. Experimental validation of a kinetic multi-component mechanism in a wide HCCI engine operating range for mixtures of n-heptane, iso-octane and toluene: Influence of EGR parameters

    International Nuclear Information System (INIS)

    Machrafi, Hatim

    2008-01-01

    The parameters that are present in exhaust gas recirculation (EGR) are believed to provide an important contribution to control the auto-ignition process of the homogeneous charge compression ignition (HCCI) in an engine. For the investigation of the behaviour of the auto-ignition process, a kinetic multi-component mechanism has been developed in former work, containing 62 reactions and 49 species for mixtures of n-heptane, iso-octane and toluene. This paper presents an experimental validation of this mechanism, comparing the calculated pressure, heat release, ignition delays and CO 2 emissions with experimental data performed on a HCCI engine. The validation is performed in a broad range of EGR parameters by varying the dilution by N 2 and CO 2 from 0 to 46 vol.%, changing the EGR temperature from 30 to 120 deg. C, altering the addition of CO and NO from 0 to 170 ppmv and varying the addition of CH 2 O from 0 to 1400 ppmv. These validations were performed respecting the HCCI conditions for the inlet temperature and the equivalence ratio. The results showed that the mechanism is validated experimentally in dilution ranges going up to 21-30 vol.%, depending on the species of dilution and over the whole range of the EGR temperature. The mechanism is validated over the whole range of CO and CH 2 O addition. As for the addition of NO, the mechanism is validated quantitatively up to 50 ppmv and qualitatively up to 170 ppmv

  20. Relevância do estado de hidratação na interpretação de parâmetros nutricionais em diálise peritoneal Relevance of hydration status on the interpretation of nutritional parameters in peritoneal dialysis

    Directory of Open Access Journals (Sweden)

    Aline de Araujo Antunes

    2011-02-01

    determinants of the hydration status of chronic peritoneal dialysis patients and investigated the effects of fluid overload on their nutritional status. METHODS: A cross-sectional study was conducted in 2006 to evaluate 27 chronic peritoneal dialysis patients from the Dialysis Center of the Medical School Hospital of Botucatu (SP, considering clinical, dialytic, laboratory, anthropometric and bioimpedance parameters. A linear multiple regression model was used to evaluate the influence of these parameters on hydration status. The sample was stratified according to hydration status, given by the ratio between extracellular water and total body water (0.47 for males and 0.52 for females, obtained by bioelectrical impedance. Analysis of covariance, Mann-Whitney test, chi-square test, and Fisher's exact test were used for making comparisons. The significance level was set at 5% (p≤0.05. RESULTS: Patients with greater urine volume and receiving automatic dialysis presented better hydration status. Patients with higher fluid overload, compared with those with lower overload, presented lower phase angle (M=4.2, SD=0.9 vs. M=5.7, SD=0.7º; p=0.006, lower albumin levels (M=3.06, SD=0.46 vs. M=3.55, SD=0.52g/dL; p=0.05, and higher percentage of triceps skinfold thickness (M=75.3, SD=36.9 vs. M= 92.1, SD=56.9; p=0.058. No other anthropometric differences were observed. CONCLUSION: Low levels of albumin and phase angle in patients with higher fluid overload were not related to worse nutritional status. This result suggests that one must consider the set of variables obtained by many methods and relate and interpret them comprehensively in order to obtain a reliable nutritional diagnosis of patients with fluid overload.

  1. SU-G-201-10: Experimental Determination of Modified TG-43 Dosimetry Parameters for the Xoft Axxent® Electronic Brachytherapy Source

    Energy Technology Data Exchange (ETDEWEB)

    Simiele, S; Palmer, B; DeWerd, L [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI (United States)

    2016-06-15

    Purpose: The establishment of an air kerma rate standard at NIST for the Xoft Axxent{sup ®} electronic brachytherapy source (Axxent{sup ®} source) motivated the establishment of a modified TG-43 dosimetry formalism. This work measures the modified dosimetry parameters for the Axxent{sup ®} source in the absence of a treatment applicator for implementation in Xoft’s treatment planning system. Methods: The dose-rate conversion coefficient (DRCC), radial dose function (RDF) values, and polar anisotropy (PA) were measured using TLD-100 microcubes with NIST-calibrated sources. The DRCC and RDF measurements were performed in liquid water using an annulus of Virtual Water™ designed to align the TLDs at the height of the anode at fixed radii from the source. The PA was measured at several distances from the source in a PMMA phantom. MCNP-determined absorbed dose energy dependence correction factors were used to convert from dose to TLD to dose to liquid water for the DRCC, RDF, and PA measurements. The intrinsic energy dependence correction factor from the work of Pike was used. The AKR was determined using a NIST-calibrated HDR1000 Plus well-type ionization chamber. Results: The DRCC was determined to be 8.6 (cGy/hr)/(µGy/min). The radial dose values were determined to be 1.00 (1cm), 0.60 (2cm), 0.42 (3cm), and 0.32 (4cm), with agreement ranging from (5.7% to 10.9%) from the work of Hiatt et al. 2015 and agreement from (2.8% to 6.8%) with internal MCNP simulations. Conclusion: This work presents a complete dataset of modified TG-43 dosimetry parameters for the Axxent{sup ®} source in the absence of an applicator. Prior to this study a DRCC had not been measured for the Axxent{sup ®} source. This data will be used for calculating dose distributions for patients receiving treatment with the Axxent{sup ®} source in Xoft’s breast balloon and vaginal applicators, and for intraoperative radiotherapy. Sources and partial funding for this work were provided by Xoft

  2. SU-G-201-10: Experimental Determination of Modified TG-43 Dosimetry Parameters for the Xoft Axxent® Electronic Brachytherapy Source

    International Nuclear Information System (INIS)

    Simiele, S; Palmer, B; DeWerd, L

    2016-01-01

    Purpose: The establishment of an air kerma rate standard at NIST for the Xoft Axxent"® electronic brachytherapy source (Axxent"® source) motivated the establishment of a modified TG-43 dosimetry formalism. This work measures the modified dosimetry parameters for the Axxent"® source in the absence of a treatment applicator for implementation in Xoft’s treatment planning system. Methods: The dose-rate conversion coefficient (DRCC), radial dose function (RDF) values, and polar anisotropy (PA) were measured using TLD-100 microcubes with NIST-calibrated sources. The DRCC and RDF measurements were performed in liquid water using an annulus of Virtual Water™ designed to align the TLDs at the height of the anode at fixed radii from the source. The PA was measured at several distances from the source in a PMMA phantom. MCNP-determined absorbed dose energy dependence correction factors were used to convert from dose to TLD to dose to liquid water for the DRCC, RDF, and PA measurements. The intrinsic energy dependence correction factor from the work of Pike was used. The AKR was determined using a NIST-calibrated HDR1000 Plus well-type ionization chamber. Results: The DRCC was determined to be 8.6 (cGy/hr)/(µGy/min). The radial dose values were determined to be 1.00 (1cm), 0.60 (2cm), 0.42 (3cm), and 0.32 (4cm), with agreement ranging from (5.7% to 10.9%) from the work of Hiatt et al. 2015 and agreement from (2.8% to 6.8%) with internal MCNP simulations. Conclusion: This work presents a complete dataset of modified TG-43 dosimetry parameters for the Axxent"® source in the absence of an applicator. Prior to this study a DRCC had not been measured for the Axxent"® source. This data will be used for calculating dose distributions for patients receiving treatment with the Axxent"® source in Xoft’s breast balloon and vaginal applicators, and for intraoperative radiotherapy. Sources and partial funding for this work were provided by Xoft Inc. (a subsidiary of i

  3. Study of the effect of some of the experimental parameters on the x-ray fluorescence determination of traces of hafnia in high purity zirconia

    International Nuclear Information System (INIS)

    Qurbani, J.M.; Khanna, P.P.; Agrawal, R.M.

    1974-01-01

    The effect of the following parameters : (i) analytical lines HfLsub(αsub(1)) or HfLsub(βsub(1,6)) or HfLsub(βsub(2)) (ii) detectors - scintillation or gas flow proportional (iii) collimators - fine or coarse (iv) x-ray tube voltage, current and power (v) order of diffraction : I or II of analysing crystal LiF (200), on the precision of the results and the sensitivity of the method in the x-ray fluorescence determination of traces of hafnia in high purity zirconia, has been studied. Philips semiautomatic x-ray spectrometer PW 1220 with associated equipment has been used. Synthetic standards containing HfO 2 in the range 20 ppm to 1 % in ZrO 2 , presented as double layer pellets have been used. LiF (200) analysing crystal, tungsten target x-ray tube, automatic pulse height selection and pulse height discrimination were used in all the cases. The set - 'HfLsub(βsub(1,6)) analytical line, fine collimator and gas flow proportional counter detector' - gave the best performance. (author)

  4. STAT3, a Key Parameter of Cytokine-driven Tissue Protection During Sterile Inflammation – the Case of Experimental Acetaminophen (Paracetamol-induced Liver Damage

    Directory of Open Access Journals (Sweden)

    Heiko eMühl

    2016-05-01

    Full Text Available Acetaminophen (APAP, N-acetyl-p-aminophenol, or paracetamol overdosing is a prevalent cause of acute liver injury. While clinical disease is initiated by overt parenchymal hepatocyte necrosis in response to the analgetic, course of intoxication is substantially influenced by associated activation of innate immunity. This process is supposed to be set in motion by release of danger associated molecular patterns (DAMPs from dying hepatocytes and is accompanied by an inflammatory cytokine response. Murine models of APAP-induced liver injury emphasize the complex role that DAMPs and cytokines play in promoting either hepatic pathogenesis or resolution and recovery from intoxication. Whereas the function of key inflammatory cytokines is controversially discussed, a subclass of specific cytokines capable of efficiently activating the hepatocyte signal transducer and activator of transcription (STAT-3 pathway stands out as being consistently protective in murine models of APAP intoxication. Those include foremost interleukin (IL-6, IL-11, IL-13, and IL-22. Above all, activation of STAT3 under the influence of these cytokines has the capability to drive hepatocyte compensatory proliferation, a key principle of the regenerating liver. Herein, the role of these specific cytokines during experimental APAP-induced liver injury is highlighted and discussed in a broader perspective. In hard-to-treat or at-risk patients standard therapy may fail and APAP intoxication can proceed towards a fatal condition. Focused administration of recombinant STAT3-activating cytokines may evolve as novel therapeutic approach under those ill-fated conditions.

  5. Determination of experimental parameters for evaluating the release of contaminants and their interaction with the environment at a waste disposal site

    International Nuclear Information System (INIS)

    Balzamo, S.; De Angelis, G.; Marchetti, A.

    1991-01-01

    A research programme has been undertaken at ENEA with the financial support of the Ministry for the Environment in the aim at evaluating the environmental impact of hazardous waste disposal. Experimental tests have been carried out in order to obtain a series of data on which models for the prediction of future contamination are based, in the frame of such programme. The release of toxic elements from solidified wastes, as well as the release mechanisms, were evaluated. The interaction between conditioned wastes and soil was assessed in laboratory, scale with the help of lysimeters using siliceous sand or natural pozzolan as simulants of ground soil. Moreover the relative mobility of different cation travelling through the soil was determined by measuring the linear distribution coefficient. Finally the permeabilities of both conditioned waste (k w ) and backfill material (k b ) were taken into account and related to each other. Due to the strict relationship existing between water permeability and cement capillary pores, measurement of cement porosity by Mercury intrusion porosimetry were also performed. The general conclusion of the research work was the validity of the data obtained needs to be confirmed by on site tests. (au)

  6. Using wavelet analysis to compare the QCD prediction and experimental data on R{sub e{sup +}e{sup -}} and to determine parameters of the charmonium states above the D anti D threshold

    Energy Technology Data Exchange (ETDEWEB)

    Henner, V.K. [University of Louisville, Department of Physics, Louisville, KY (United States); Perm State University, Department of Theoretical Physics, Perm (Russian Federation); Perm State Technical University, Department of Mathematics, Perm (Russian Federation); Davis, C.L. [University of Louisville, Department of Physics, Louisville, KY (United States); Belozerova, T.S. [Perm State University, Department of Theoretical Physics, Perm (Russian Federation)

    2015-10-15

    The first part of our analysis uses the wavelet method to compare the quantum chromodynamic (QCD) prediction for the ratio of hadronic to muon cross sections in electron-positron collisions, R, with experimental data for R over a center of mass energy range up to about 7 GeV. A direct comparison of the raw experimental data and the QCD prediction is difficult because the data have a wide range of structures and large statistical errors and the QCD description contains sharp quark-antiquark thresholds. However, a meaningful comparison can be made if a type of ''smearing'' procedure is used to smooth out rapid variations in both the theoretical and experimental values of R. A wavelet analysis (WA) can be used to achieve this smearing effect. The second part of the analysis concentrates on the 3.0-6.0 GeV energy region which includes the relatively wide charmonium resonances ψ(1{sup -}). We use the wavelet methodology to distinguish these resonances from experimental noise, background and from each other, allowing a reliable determination of the parameters of these states. Both analyses are examples of the usefulness of WA in extracting information in a model independent way from high energy physics data. (orig.)

  7. Exploration of parameters influencing the self-absorption losses in luminescent solar concentrators with an experimentally validated combined ray-tracing/Monte-Carlo model

    Science.gov (United States)

    Krumer, Zachar; van Sark, Wilfried G. J. H. M.; de Mello Donegá, Celso; Schropp, Ruud E. I.

    2013-09-01

    Luminescent solar concentrators (LSCs) are low cost photovoltaic devices, which reduce the amount of necessary semiconductor material per unit area of a photovoltaic solar energy converter by means of concentration. The device is comprised of a thin plastic plate in which luminescent species (fluorophores) have been incorporated.The fluorophores absorb the solar light and radiatively re-emit a part of the energy. Total internal reflection traps most of the emitted light inside the plate and wave-guides it to a narrow side facet with a solar cell attached, where conversion into electricity occurs. The eciency of such devices is as yet rather low, due to several loss mechanisms, of which self-absorption is of high importance. Combined ray-tracing and Monte-Carlosimulations is a widely used tool for efficiency estimations of LSC-devices prior to manufacturing. We have applied this method to a model experiment, in which we analysed the impact of self-absorption onto LSC-efficiency of fluorophores with different absorption/emission-spectral overlap (Stokes-shift): several organic dyes and semiconductor quantum dots (single compound and core/shell of type-II). These results are compared with the ones obtained experimentally demonstrating a good agreement. The validated model is used to investigate systematically the influence of spectral separation and luminescence quantum efficiency on the intensity loss inconsequence of increased self-absorption. The results are used to adopt a quantity called the self-absorption cross-section and establish it as reliable criterion for self-absorption properties of materials that can be obtained from fundamental data and has a more universal scope of application, than the currently used Stokes-shift.

  8. Study of relevant parameters of GEM-based detectors

    CERN Document Server

    Croci, Gabriele; Sauli, Fabio; Ragazzi, S

    2007-01-01

    The Gas Electron Multiplier consist of a thin Kapton insulating (50 $\\mu$m) foil copper-clad on both sides and perforated by a high density, regular matrix of holes (around 100 per square millimeter). Typically the distance between holes (pitch) is 140 $\\mu$m and diameters of about 70 $\\mu$m. The mesh is realised by conventional photolitographic methods as used for the fabrication of multi-layer board. Upon application of a potential difference between the GEM electrodes, a high dipole field develops in the holes focusing the field lines between the drift electrode and the readout element. Electron drift along the channel and the charge is amplified by a factor that depends on the field density and the length of the channel. Owing to their excellent position resolution and rate capability GEM-based detector are very suitable to be used in different applications: from the high energy physics to the medical field. The GEM temporal and rate gain stability was studied and it was discovered that the gain variation...

  9. Culturally Relevant Cyberbullying Prevention

    OpenAIRE

    Phillips, Gregory John

    2017-01-01

    In this action research study, I, along with a student intervention committee of 14 members, developed a cyberbullying intervention for a large urban high school on the west coast. This high school contained a predominantly African American student population. I aimed to discover culturally relevant cyberbullying prevention strategies for African American students. The intervention committee selected video safety messages featuring African American actors as the most culturally relevant cyber...

  10. Computational Design of Short Pulse Laser Driven Iron Opacity Measurements at Stellar-Relevant Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madison E. [Univ. of Florida, Gainesville, FL (United States)

    2017-05-20

    Opacity is a critical parameter in the simulation of radiation transport in systems such as inertial con nement fusion capsules and stars. The resolution of current disagreements between solar models and helioseismological observations would bene t from experimental validation of theoretical opacity models. Overall, short pulse laser heated iron experiments reaching stellar-relevant conditions have been designed with consideration of minimizing tamper emission and optical depth effects while meeting plasma condition and x-ray emission goals.

  11. Elucidation of mechanisms of actions of thymoquinone-enriched methanolic and volatile oil extracts from Nigella sativa against cardiovascular risk parameters in experimental hyperlipidemia.

    Science.gov (United States)

    Ahmad, Shafeeque; Beg, Zafarul H

    2013-06-13

    extracts especially, ME significantly improve cardiovascular risk parameters in treated rats, and can be used in reactive oxygen species disorders such as cardiovascular diseases.

  12. Using dynamic N-mixture models to test cavity limitation on northern flying squirrel demographic parameters using experimental nest box supplementation.

    Science.gov (United States)

    Priol, Pauline; Mazerolle, Marc J; Imbeau, Louis; Drapeau, Pierre; Trudeau, Caroline; Ramière, Jessica

    2014-06-01

    Dynamic N-mixture models have been recently developed to estimate demographic parameters of unmarked individuals while accounting for imperfect detection. We propose an application of the Dail and Madsen (2011: Biometrics, 67, 577-587) dynamic N-mixture model in a manipulative experiment using a before-after control-impact design (BACI). Specifically, we tested the hypothesis of cavity limitation of a cavity specialist species, the northern flying squirrel, using nest box supplementation on half of 56 trapping sites. Our main purpose was to evaluate the impact of an increase in cavity availability on flying squirrel population dynamics in deciduous stands in northwestern Québec with the dynamic N-mixture model. We compared abundance estimates from this recent approach with those from classic capture-mark-recapture models and generalized linear models. We compared apparent survival estimates with those from Cormack-Jolly-Seber (CJS) models. Average recruitment rate was 6 individuals per site after 4 years. Nevertheless, we found no effect of cavity supplementation on apparent survival and recruitment rates of flying squirrels. Contrary to our expectations, initial abundance was not affected by conifer basal area (food availability) and was negatively affected by snag basal area (cavity availability). Northern flying squirrel population dynamics are not influenced by cavity availability at our deciduous sites. Consequently, we suggest that this species should not be considered an indicator of old forest attributes in our study area, especially in view of apparent wide population fluctuations across years. Abundance estimates from N-mixture models were similar to those from capture-mark-recapture models, although the latter had greater precision. Generalized linear mixed models produced lower abundance estimates, but revealed the same relationship between abundance and snag basal area. Apparent survival estimates from N-mixture models were higher and less precise

  13. [Determination of deuterium concentration in foods and influence of water with modified isotopic composition on oxidation parameters and heavy hydrogen isotopes content in experimental animals].

    Science.gov (United States)

    Basov, A A; Bykov, I M; Baryshev, M G; Dzhimak, S S; Bykov, M I

    2014-01-01

    The article presents the results of the study of the deuterium (D) content in food products as well as the influence of deuterium depleted water (DDW) on the concentration of heavy hydrogen isotopes in the blood and lyophilized tissues of rats. The most significant difference in the content of D was found between potato and pork fat, which indexes the standard delta notation (δ) D in promille, related to the international standard SMOW (Standard Mean Ocean of Water) amounted to -83,2 per thousand and -250,7 per thousand, respectively (phydrogen atoms in the body. The data obtained in the experimental modeling of the diet of male Wistar rats in the age of 5-6 mo (weight 235 ± 16 g) using DDW (δD = -743,2 per thousand) instead of drinking water (δD = -37,0 per thousand) with identical mineral composition showed that after 2 weeks significant (p tissue") is due to different rates ofisotopic exchange reactions in plasma and tissues (liver, kidney, heart), which can be explained by entering into the composition of a modified diet of organic substrates with more than DDW concentration D, which are involved in the construction of cellular structures and eventually lead to a redistribution of D and change direction of D/H gradient "plasma

  14. Comparison of CFD simulations with experimental Jet Erosion Tests results

    OpenAIRE

    Mercier, F.; Bonelli, S.; Pinettes, P.; Golay, F.; Anselmet, F.; Philippe, P.

    2014-01-01

    The Jet Erosion Test (JET) is an experimental device increasingly used to quantify the resistance of soils to erosion. This resistance is characterised by two geotechnical parameters: the critical shear stress and the erosion coefficient. The JET interpretation model of Hanson and Cook (2004) provides an estimation of these erosion parameters. But Hanson's model is simplified, semi-empirical and several assumed hypotheses can be discussed. Our aim is to determine the relevance of the JET inte...

  15. Purified deoxynivalenol or feed restriction reduces mortality in rainbow trout, Oncorhynchus mykiss (Walbaum), with experimental bacterial coldwater disease but biologically relevant concentrations of deoxynivalenol do not impair the growth of Flavobacterium psychrophilum.

    Science.gov (United States)

    Ryerse, I A; Hooft, J M; Bureau, D P; Hayes, M A; Lumsden, J S

    2015-09-01

    Diets containing deoxynivalenol (DON) were fed to rainbow trout Oncorhynchus mykiss (Walbaum) for 4 weeks followed by experimental infection (intraperitoneal) with Flavobacterium psychrophilum (4.1 × 10(6) colony-forming units [CFU] mL(-1) ). Mortality of rainbow trout fed either 6.4 mg kg(-1) DON or trout pair-fed the control diet was significantly reduced (P trout fed the control diet to apparent satiation (trout were fed one of three experimental diets; a control diet, a diet produced with corn naturally contaminated with DON (3.3 mg kg(-1) DON) or a diet containing purified DON (3.8 mg kg(-1) ); however, these fish were not experimentally infected. The presence of DON resulted in significant reduction (P trout fed diets containing purified DON (3.8 mg kg(-1) ) was significantly higher (P < 0.05) at 35 day post-exposure compared with controls. The antimicrobial activity of DON was examined by subjecting F. psychrophilum in vitro to serial dilutions of the chemical. Complete inhibition occurred at a concentration of 75 mg L(-1) DON, but no effect was observed below this concentration (0-30 mg L(-1) ). © 2014 John Wiley & Sons Ltd.

  16. Experimental validation of a kinetic multi-component mechanism in a wide HCCI engine operating range for mixtures of n-heptane, iso-octane and toluene: Influence of EGR parameters

    Energy Technology Data Exchange (ETDEWEB)

    Machrafi, Hatim [LGPPTS, Ecole Nationale Superieure de Chimie de Paris/ Universite Pierre et Marie Curie (Paris 6), 11, rue de Pierre et Marie Curie, 75231 Paris Cedex 05 (France)

    2008-11-15

    The parameters that are present in exhaust gas recirculation (EGR) are believed to provide an important contribution to control the auto-ignition process of the homogeneous charge compression ignition (HCCI) in an engine. For the investigation of the behaviour of the auto-ignition process, a kinetic multi-component mechanism has been developed in former work, containing 62 reactions and 49 species for mixtures of n-heptane, iso-octane and toluene. This paper presents an experimental validation of this mechanism, comparing the calculated pressure, heat release, ignition delays and CO{sub 2} emissions with experimental data performed on a HCCI engine. The validation is performed in a broad range of EGR parameters by varying the dilution by N{sub 2} and CO{sub 2} from 0 to 46 vol.%, changing the EGR temperature from 30 to 120 C, altering the addition of CO and NO from 0 to 170 ppmv and varying the addition of CH{sub 2}O from 0 to 1400 ppmv. These validations were performed respecting the HCCI conditions for the inlet temperature and the equivalence ratio. The results showed that the mechanism is validated experimentally in dilution ranges going up to 21-30 vol.%, depending on the species of dilution and over the whole range of the EGR temperature. The mechanism is validated over the whole range of CO and CH{sub 2}O addition. As for the addition of NO, the mechanism is validated quantitatively up to 50 ppmv and qualitatively up to 170 ppmv. (author)

  17. The Limits to Relevance

    Science.gov (United States)

    Averill, M.; Briggle, A.

    2006-12-01

    Science policy and knowledge production lately have taken a pragmatic turn. Funding agencies increasingly are requiring scientists to explain the relevance of their work to society. This stems in part from mounting critiques of the "linear model" of knowledge production in which scientists operating according to their own interests or disciplinary standards are presumed to automatically produce knowledge that is of relevance outside of their narrow communities. Many contend that funded scientific research should be linked more directly to societal goals, which implies a shift in the kind of research that will be funded. While both authors support the concept of useful science, we question the exact meaning of "relevance" and the wisdom of allowing it to control research agendas. We hope to contribute to the conversation by thinking more critically about the meaning and limits of the term "relevance" and the trade-offs implicit in a narrow utilitarian approach. The paper will consider which interests tend to be privileged by an emphasis on relevance and address issues such as whose goals ought to be pursued and why, and who gets to decide. We will consider how relevance, narrowly construed, may actually limit the ultimate utility of scientific research. The paper also will reflect on the worthiness of research goals themselves and their relationship to a broader view of what it means to be human and to live in society. Just as there is more to being human than the pragmatic demands of daily life, there is more at issue with knowledge production than finding the most efficient ways to satisfy consumer preferences or fix near-term policy problems. We will conclude by calling for a balanced approach to funding research that addresses society's most pressing needs but also supports innovative research with less immediately apparent application.

  18. Parameter Estimation

    DEFF Research Database (Denmark)

    Sales-Cruz, Mauricio; Heitzig, Martina; Cameron, Ian

    2011-01-01

    of optimisation techniques coupled with dynamic solution of the underlying model. Linear and nonlinear approaches to parameter estimation are investigated. There is also the application of maximum likelihood principles in the estimation of parameters, as well as the use of orthogonal collocation to generate a set......In this chapter the importance of parameter estimation in model development is illustrated through various applications related to reaction systems. In particular, rate constants in a reaction system are obtained through parameter estimation methods. These approaches often require the application...... of algebraic equations as the basis for parameter estimation.These approaches are illustrated using estimations of kinetic constants from reaction system models....

  19. Relevant Subspace Clustering

    DEFF Research Database (Denmark)

    Müller, Emmanuel; Assent, Ira; Günnemann, Stephan

    2009-01-01

    Subspace clustering aims at detecting clusters in any subspace projection of a high dimensional space. As the number of possible subspace projections is exponential in the number of dimensions, the result is often tremendously large. Recent approaches fail to reduce results to relevant subspace...... clusters. Their results are typically highly redundant, i.e. many clusters are detected multiple times in several projections. In this work, we propose a novel model for relevant subspace clustering (RESCU). We present a global optimization which detects the most interesting non-redundant subspace clusters...... achieves top clustering quality while competing approaches show greatly varying performance....

  20. New experimental determination of the neutronic resonance parameters of {sup 237}Np below 500 eV; Nouvelle determination experimentale des parametres de resonances neutroniques de {sup 237}Np en dessous de 500 eV

    Energy Technology Data Exchange (ETDEWEB)

    Gressier, V

    1999-10-01

    For studies of future nuclear reactors dedicated to nuclear waste transmutation, an improvement of the accuracy of the neutron radiative capture cross section of {sup 237}Np appears necessary. In the framework of a collaboration between the Commissariat a l'Energie atomique (CEA) and Institute for Reference Materials and Measurement (IRMM, Geel, Bergium), a new determination of the resonance parameters of {sup 237}Np has been performed. Two types of experiments are carried out at GELINA, the IRMM pulsed neutron source, using the time of flight method: a transmission experiment which is related to the neutron total cross section and a capture experiment which gives the neutron radiative capture cross section. The resonance parameters presented in this work are extracted from the transmission data between 0 and 500 eV with the least square code REFIT, using the Reich-Moore formalism. In parallel, the Doppler effect is investigated. The commonly used free gas model appears inadequate below 20 eV for neptunium dioxide at room temperature. By the use of the program DOPUSH, which calculates the Doppler broadening with a harmonic crystal model according to Lamb's theory, we are able to produce abetter fit of the experimental data for the resonances of {sup 237}Np in NpO{sub 2} at low energy or temperatures. In addition to the resonance parameters, a study of their mean value and distribution is included in this work. (authors)

  1. SITE-94. Chemical and physical transport parameters for SITE-94

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Karin [Chalmers Univ. of Technology, Goeteborg (Sweden). Technical Environmental Planning

    1996-02-01

    Important parameters are the interactions of radionuclides with solid surfaces, parameters describing the geometrical conditions like porosity, data on water composition (ionic strength, pH, redox conditions, complex formers etc) and data on the solids that may be of importance to the water and radionuclide chemistry. In this report some of these data of relevance for the Aespoe site are discussed. Based on a literature survey, sorption data as well as values for some other parameters have been selected for rock, fracture fillings and bentonite relevant to the chemical conditions in and around a repository at Aespoe. A comparison to data used for earlier, site-specific as well as general, safety assessments of underground repositories has been performed. The data are recommendations for modelling of radionuclide release from a hypothetical high level waste repository at Aespoe. Since the data to a large extent are not based on experimental measurements, more accurate predictions may be expected if more experimental data are available. Before such studies are performed for a specific site, a variational analysis in order to evaluate the importance of the single parameters is recommended. After such a study, the key parameters may be investigated in detail and the modelling can be expected to be more accurate what concerns influence of single parameters. However, the uncertainty in conceptual areas like how to model accurately the long term hydrology of the site etc still remains. 32 refs.

  2. Is Information Still Relevant?

    Science.gov (United States)

    Ma, Lia

    2013-01-01

    Introduction: The term "information" in information science does not share the characteristics of those of a nomenclature: it does not bear a generally accepted definition and it does not serve as the bases and assumptions for research studies. As the data deluge has arrived, is the concept of information still relevant for information…

  3. Evaporation and vapor shielding of CFC targets exposed to plasma heat fluxes relevant to ITER ELMs

    International Nuclear Information System (INIS)

    Safronov, V.M.; Arkhipov, N.I.; Landman, I.S.; Pestchanyi, S.E.; Toporkov, D.A.; Zhitlukhin, A.M.

    2009-01-01

    Carbon fibre composite NB31 was tested at plasma gun facility MK-200UG by plasma heat fluxes relevant to Edge Localised Modes in ITER. The paper reports the results obtained on the evaporation threshold of carbon fibre composite, the velocity of carbon vapor motion along and across the magnetic field lines, and the parameters of carbon plasma such as temperature, density and ionization state. First experimental results on investigation of the vapor shield onset conditions are presented also. The obtained experimental data are compared with the results of numerical modeling.

  4. CALPHAD simulation of the Mg–(Mn, Zr)–Fe system and experimental comparison with as-cast alloy microstructures as relevant to impurity driven corrosion of Mg-alloys

    Energy Technology Data Exchange (ETDEWEB)

    Gandel, D.S., E-mail: darren.gandel@monash.edu [CAST Cooperative Research Centre (Australia); Department of Materials Engineering, Monash University, Clayton, VIC 3800 (Australia); Easton, M.A. [CAST Cooperative Research Centre (Australia); Department of Materials Engineering, Monash University, Clayton, VIC 3800 (Australia); Gibson, M.A. [CAST Cooperative Research Centre (Australia); CSIRO Process Science and Engineering, Clayton, VIC 3168 (Australia); Birbilis, N. [CAST Cooperative Research Centre (Australia); Department of Materials Engineering, Monash University, Clayton, VIC 3800 (Australia)

    2014-02-14

    Four Mg alloys with variations in the ratio of Mn, Zr and Fe additions were cast and their microstructures analysed via electron microscopy. Thermodynamic calculations of the expected phases using PANDAT were evaluated with actual as-cast microstructures. Some of the as-cast alloys did appear to form phases similar to those anticipated from the PANDAT calculations. Furthermore, there was a new Mn–Fe particle interaction observed that was not predicted, but which is posited to be responsible for the increase in corrosion resistance among Mn containing Mg alloys with Fe impurities. The experimental work herein has been shown to be invaluable in the understanding of this practically important system with sparingly soluble Fe and its potential influence on the corrosion of Mg alloys. - Highlights: • Alloy microstructure of the Mg-(Mn,Zr, Fe) system was analysed and reported. • CALPHAD analysis was used in conjunction with traditional SEM analysis techniques in this study. • A proposed Mn–Fe interaction within Mg has been observed for the first time. • Experimental validation of calculated phases is required to understand the effect of Mn and Zr on Mg.

  5. Optimising imaging parameters in experimental spiral CT

    International Nuclear Information System (INIS)

    Tiitola, M.; Vehmas, T.; Kivisaari, R.P.; Kivisaari, L.

    1997-01-01

    Purpose: This in vitro study was conducted to analyse lesion detection and relative radiation exposure in different CT techniques. Material and Methods: We used a plastic phantom (12 x 8 x 2 cm) containing holes filled with air or fluid of varying densities to simulate lesions. This was imaged with Siemens Somatom Plus S and GE High Speed Advantage units. We varied table feeds (3 and 6 mm/s in Siemens and 3 and 4.5 mm/s in GE) and increments (2 mm and 4 mm) while keeping collimation at 3 mm. The SmartScan program of GE and the reformating algorithm of Siemens were also analysed. To evaluate the different methods, the phatnom lesions were counted by 3 observers. Radiation exposures associated with each technique were also measured. Results: The images reformatted to a coronal direction were significantly inferior (p<0.01) to those in other techniques. The use of SmartScan did not influence lesion detection, nor did changes in pitch or increment. Spiral and non-spiral techniques proved to be equal. Radiation exposure was lowest when a greater pitch or the SmartScan program was used. Conclusion: Radiation exposure in CT can be limited without significantly impairing the image quality by using low-dose techniques. Reformatting to a coronal direction should be used with care as it debases the image quality. (orig.)

  6. Optimization of Experimental Parameters in preparing ...

    African Journals Online (AJOL)

    NICO

    2012-11-14

    Nov 14, 2012 ... Titanium films, anodic oxidation, multinanoporous films, photocatalytic activity. 1. .... 0.2 mol dm–3 methanol solution as an organic pollutant model in ..... obtained at lower cost by electrochemical oxidation on a titanium.

  7. Optimal Experimental Design for Large-Scale Bayesian Inverse Problems

    KAUST Repository

    Ghattas, Omar

    2014-01-06

    We develop a Bayesian framework for the optimal experimental design of the shock tube experiments which are being carried out at the KAUST Clean Combustion Research Center. The unknown parameters are the pre-exponential parameters and the activation energies in the reaction rate expressions. The control parameters are the initial mixture composition and the temperature. The approach is based on first building a polynomial based surrogate model for the observables relevant to the shock tube experiments. Based on these surrogates, a novel MAP based approach is used to estimate the expected information gain in the proposed experiments, and to select the best experimental set-ups yielding the optimal expected information gains. The validity of the approach is tested using synthetic data generated by sampling the PC surrogate. We finally outline a methodology for validation using actual laboratory experiments, and extending experimental design methodology to the cases where the control parameters are noisy.

  8. Clinical Relevance of Adipokines

    Directory of Open Access Journals (Sweden)

    Matthias Blüher

    2012-10-01

    Full Text Available The incidence of obesity has increased dramatically during recent decades. Obesity increases the risk for metabolic and cardiovascular diseases and may therefore contribute to premature death. With increasing fat mass, secretion of adipose tissue derived bioactive molecules (adipokines changes towards a pro-inflammatory, diabetogenic and atherogenic pattern. Adipokines are involved in the regulation of appetite and satiety, energy expenditure, activity, endothelial function, hemostasis, blood pressure, insulin sensitivity, energy metabolism in insulin sensitive tissues, adipogenesis, fat distribution and insulin secretion in pancreatic β-cells. Therefore, adipokines are clinically relevant as biomarkers for fat distribution, adipose tissue function, liver fat content, insulin sensitivity, chronic inflammation and have the potential for future pharmacological treatment strategies for obesity and its related diseases. This review focuses on the clinical relevance of selected adipokines as markers or predictors of obesity related diseases and as potential therapeutic tools or targets in metabolic and cardiovascular diseases.

  9. Information Needs/Relevance

    OpenAIRE

    Wildemuth, Barbara M.

    2009-01-01

    A user's interaction with a DL is often initiated as the result of the user experiencing an information need of some kind. Aspects of that experience and how it might affect the user's interactions with the DL are discussed in this module. In addition, users continuously make decisions about and evaluations of the materials retrieved from a DL, relative to their information needs. Relevance judgments, and their relationship to the user's information needs, are discussed in this module. Draft

  10. Topology of the interactions pattern in pharmaceutically relevant polymorphs of methylxanthines (caffeine, theobromine, and theophiline): combined experimental (¹H-¹⁴N nuclear quadrupole double resonance) and computational (DFT and Hirshfeld-based) study.

    Science.gov (United States)

    Latosińska, Jolanta Natalia; Latosińska, Magdalena; Olejniczak, Grzegorz A; Seliger, Janez; Žagar, Veselko

    2014-09-22

    Three anhydrous methylxanthines: caffeine (1,3,7-trimethylxanthine; 1,3,7-trimethyl-1H-purine-2,6-(3H,7H)-dione) and its two metabolites theophylline (1,3-dimethylxanthine; 1,3-dimethyl-7H-purine-2,6-dione) and theobromine (3,7-dimethyl-xanthine; 3,7-dimethyl-7H-purine-2,6-dione), which reveal multifaceted therapeutic potential, have been studied experimentally in solid state by (1)H-(14)N NMR-NQR (nuclear magnetic resonance-nuclear quadrupole resonance) double resonance (NQDR). For each compound the complete NQR spectrum consisting of 12 lines was recorded. The multiplicity of NQR lines indicates the presence of a stable β form of anhydrous caffeine at 233 K and stable form II of anhydrous theobromine at 213 K. The assignment of signals detected in NQR experiment to particular nitrogen atoms was made on the basis of quantum chemistry calculations performed for monomer, cluster, and solid at the DFT/GGA/BLYP/DPD level. The shifts due to crystal packing interactions were evaluated, and the multiplets detected by NQR were assigned to N(9) in theobromine and N(1) and N(9) in caffeine. The ordering theobromine > theophylline > caffeine site and theophylline theobromine theobromine) to π···π stacking (caffeine). Substantial differences in the intermolecular interactions in stable forms of methylxanthines differing in methylation (site or number) were analyzed within the Hirshfeld surface-based approach. The analysis of local environment of the nitrogen nucleus permitted drawing some conclusions on the nature of the interactions required for effective processes of recognition and binding of a given methylxanthine to A1-A(2A) receptor (target for caffeine in the brain). Although the interactions responsible for linking neighboring methylxanthines molecules in crystals and methylxanthines with targets in the human organism can differ significantly, the knowledge of the topology of interactions provides reliable preliminary information about the nature of this binding.

  11. Wavelet theory and belt finishing process, influence of wavelet shape on the surface roughness parameter values

    International Nuclear Information System (INIS)

    Khawaja, Z; Mazeran, P-E; Bigerelle, M; Guillemot, G; Mansori, M El

    2011-01-01

    This article presents a multi-scale theory based on wavelet decomposition to characterize the evolution of roughness in relation with a finishing process or an observed surface property. To verify this approach in production conditions, analyses were developed for the finishing process of the hardened steel by abrasive belts. These conditions are described by seven parameters considered in the Tagushi experimental design. The main objective of this work is to identify the most relevant roughness parameter and characteristic length allowing to assess the influence of finishing process, and to test the relevance of the measurement scale. Results show that wavelet approach allows finding this scale.

  12. [Relevant public health enteropathogens].

    Science.gov (United States)

    Riveros, Maribel; Ochoa, Theresa J

    2015-01-01

    Diarrhea remains the third leading cause of death in children under five years, despite recent advances in the management and prevention of this disease. It is caused by multiple pathogens, however, the prevalence of each varies by age group, geographical area and the scenario where cases (community vs hospital) are recorded. The most relevant pathogens in public health are those associated with the highest burden of disease, severity, complications and mortality. In our country, norovirus, Campylobacter and diarrheagenic E. coli are the most prevalent pathogens at the community level in children. In this paper we review the local epidemiology and potential areas of development in five selected pathogens: rotavirus, norovirus, Shiga toxin-producing E. coli (STEC), Shigella and Salmonella. Of these, rotavirus is the most important in the pediatric population and the main agent responsible for child mortality from diarrhea. The introduction of rotavirus vaccination in Peru will have a significant impact on disease burden and mortality from diarrhea. However, surveillance studies are needed to determine the impact of vaccination and changes in the epidemiology of diarrhea in Peru following the introduction of new vaccines, as well as antibiotic resistance surveillance of clinical relevant bacteria.

  13. Other relevant biological papers

    International Nuclear Information System (INIS)

    Shimizu, M.

    1989-01-01

    A considerable number of CRESP-relevant papers concerning deep-sea biology and radioecology have been published. It is the purpose of this study to call attention to them. They fall into three general categories. The first is papers of general interest. They are mentioned only briefly, and include text references to the global bibliography at the end of the volume. The second are papers that are not only mentioned and referenced, but for various reasons are described in abstract form. The last is a list of papers compiled by H.S.J. Roe specifically for this volume. They are listed in bibliographic form, and are also included in the global bibliography at the end of the volume

  14. New conducted electrical weapons: Electrical safety relative to relevant standards.

    Science.gov (United States)

    Panescu, Dorin; Nerheim, Max; Kroll, Mark W; Brave, Michael A

    2017-07-01

    We have previously published about TASER ® conducted electrical weapons (CEW) compliance with international standards. CEWs deliver electrical pulses that can inhibit a person's neuromuscular control or temporarily incapacitate. An eXperimental Rotating-Field (XRF) waveform CEW and the X2 CEW are new 2-shot electrical weapon models designed to target a precise amount of delivered charge per pulse. They both can deploy 1 or 2 dart pairs, delivered by 2 separate cartridges. Additionally, the XRF controls delivery of incapacitating pulses over 4 field vectors, in a rotating sequence. As in our previous study, we were motivated by the need to understand the cardiac safety profile of these new CEWs. The goal of this paper is to analyze the nominal electrical outputs of TASER XRF and X2 CEWs in reference to provisions of all relevant international standards that specify safety requirements for electrical medical devices and electrical fences. Although these standards do not specifically mention CEWs, they are the closest electrical safety standards and hence give very relevant guidance. The outputs of several TASER XRF and X2 CEWs were measured under normal operating conditions. The measurements were compared against manufacturer specifications. CEWs electrical output parameters were reviewed against relevant safety requirements of UL 69, IEC 60335-2-76 Ed 2.1, IEC 60479-1, IEC 60479-2, AS/NZS 60479.1, AS/NZS 60479.2, IEC 60601-1 and BS EN 60601-1. Our study confirmed that the nominal electrical outputs of TASER XRF and X2 CEWs lie within safety bounds specified by relevant standards.

  15. Systematic of delayed neutron parameters

    International Nuclear Information System (INIS)

    Isaev, S.G.; Piksaikin, V.M.

    2000-01-01

    The experimental studies of the energy dependence of the delayed neutron (DN) parameters for various fission systems has shown that the behaviour of a some combination of delayed neutron parameters has a similar features. On the basis of this findings the systematics of delayed neutron experimental data for thorium, uranium, plutonium and americium isotopes have been investigated with the purpose to find a correlation of DN parameters with characteristics of fissioning system as well as a correlation between the delayed neutron parameters themselves. It was presented the preliminary results which were obtained during study the physics interpretation of the results [ru

  16. User perspectives on relevance criteria

    DEFF Research Database (Denmark)

    Maglaughlin, Kelly L.; Sonnenwald, Diane H.

    2002-01-01

    , partially relevant, or not relevant to their information need; and explained their decisions in an interview. Analysis revealed 29 criteria, discussed positively and negatively, that were used by the participants when selecting passages that contributed or detracted from a document's relevance......This study investigates the use of criteria to assess relevant, partially relevant, and not-relevant documents. Study participants identified passages within 20 document representations that they used to make relevance judgments; judged each document representation as a whole to be relevant...... matter, thought catalyst), full text (e.g., audience, novelty, type, possible content, utility), journal/publisher (e.g., novelty, main focus, perceived quality), and personal (e.g., competition, time requirements). Results further indicate that multiple criteria are used when making relevant, partially...

  17. Copper(II) complex with 6-methylpyridine-2-carboxyclic acid: Experimental and computational study on the XRD, FT-IR and UV-Vis spectra, refractive index, band gap and NLO parameters.

    Science.gov (United States)

    Altürk, Sümeyye; Avcı, Davut; Başoğlu, Adil; Tamer, Ömer; Atalay, Yusuf; Dege, Necmi

    2018-02-05

    Crystal structure of the synthesized copper(II) complex with 6-methylpyridine-2-carboxylic acid, [Cu(6-Mepic) 2 ·H 2 O]·H 2 O, was determined by XRD, FT-IR and UV-Vis spectroscopic techniques. Furthermore, the geometry optimization, harmonic vibration frequencies for the Cu(II) complex were carried out by using Density Functional Theory calculations with HSEh1PBE/6-311G(d,p)/LanL2DZ level. Electronic absorption wavelengths were obtained by using TD-DFT/HSEh1PBE/6-311G(d,p)/LanL2DZ level with CPCM model and major contributions were determined via Swizard/Chemissian program. Additionally, the refractive index, linear optical (LO) and non-nonlinear optical (NLO) parameters of the Cu(II) complex were calculated at HSEh1PBE/6-311G(d,p) level. The experimental and computed small energy gap shows the charge transfer in the Cu(II) complex. Finally, the hyperconjugative interactions and intramolecular charge transfer (ICT) were studied by performing of natural bond orbital (NBO) analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. An experimental and numerical analysis of the HCCI auto-ignition process of primary reference fuels, toluene reference fuels and diesel fuel in an engine, varying the engine parameters

    Energy Technology Data Exchange (ETDEWEB)

    Machrafi, Hatim; Cavadias, Simeon [UPMC Universite Paris 06, LGPPTS, Ecole Nationale Superieure de Chimie de Paris, 11, rue de Pierre et Marie Curie, 75005 Paris (France); UPMC Universite Paris 06, Institut Jean Le Rond D' Alembert, 2, place de la Gare de Ceinture, 78210 St Cyr-I' Ecole (France); Gilbert, Philippe [UPMC Universite Paris 06, Institut Jean Le Rond D' Alembert, 2, place de la Gare de Ceinture, 78210 St Cyr-I' Ecole (France)

    2008-11-15

    For a future HCCI engine to operate under conditions that adhere to environmental restrictions, reducing fuel consumption and maintaining or increasing at the same time the engine efficiency, the choice of the fuel is crucial. For this purpose, this paper presents an auto-ignition investigation concerning the primary reference fuels, toluene reference fuels and diesel fuel, in order to study the effect of linear alkanes, branched alkanes and aromatics on the auto-ignition. The auto-ignition of these fuels has been studied at inlet temperatures from 25 to 120 C, at equivalence ratios from 0.18 to 0.53 and at compression ratios from 6 to 13.5, in order to extend the range of investigation and to assess the usability of these parameters to control the auto-ignition. It appeared that both iso-octane and toluene delayed the ignition with respect to n-heptane, while toluene has the strongest effect. This means that aromatics have higher inhibiting effects than branched alkanes. In an increasing order, the inlet temperature, equivalence ratio and compression ratio had a promoting effect on the ignition delays. A previously experimentally validated reduced surrogate mechanism, for mixtures of n-heptane, iso-octane and toluene, has been used to explain observations of the auto-ignition process. (author)

  19. Evaluation of semen parameters of boars (Sus scrofa experimentally infected with Toxoplasma gondii/ Avaliação dos parâmetros seminais de cachaços (Sus scrofa experimentalmente infectados com Toxoplasma gondii

    Directory of Open Access Journals (Sweden)

    Alvimar José da Costa

    2004-05-01

    Full Text Available Aiming to investigate the influence of T. gondii on semen parameters and spermatozoa morphology, eight boars were inoculated with T. gondii. Experimental groups consisted of: GI (n=3 1,5 x 104 oocysts of P strain; GII (n=3 1,0 x 106 tachyzoites of RH strain and GIII (n=2, control noninoculated. Evaluations of semen parameters (volume, motility, strength, concentration, study of spermatozoa morphology, serology (RIFI, parasitemia and hemograms were performed. For this purpose, blood and semen collection were carried out on days -2, -1, 1, 3, 5, 7, 9, 11, 14 and weekly until 84 days post-inoculation. Non hematimetrics alterations and clinical signs were observed on animals. Parasitemia was detected in an animal inoculated with oocysts, on the 7th day post inoculation (DPI and in a two pigs of GII (tachyzoites, on the 3rd and 49th DPI. Serology results revealed the presence of antibody anti-T. gondii on the animals inoculated with oocysts or tachyzoites since 7th DPI, with tittles of 256 and 64, reaching a maximal level of 4096 on days 11 and 9 post inoculation, respectively. The GIII (control was negative through out all experimental period. The semen parametersevaluated did not present any alteration due to toxoplasmosis. Significative differences (PCom o objetivo de investigar a influência do Toxoplasma gondii nos parâmetros seminais e na morfologia espermática de suínos, oito reprodutores foram inoculados com T. gondii, sendo constituídos os seguintes grupos experimentais: GI (n=3 1,5 x 104 oocistos da cepa P, via oral; GII (n=3 1,0 x 106 taquizoítos da cepa RH, via subcutânea e GIII (n=2, controle. Foram realizadas avaliações de parâmetros espermáticos (volume, motilidade, vigor, concentração, estudo da morfologia dos espermatozóides, exames sorológicos(RIFI, parasitemia e hemogramas. Para tanto, colheitas de sangue e sêmen foram realizadas nos dia -2, -1, 1, 3, 5, 7, 9, 11, 14 e semanalmente até 84 dias p

  20. Bomb parameters

    International Nuclear Information System (INIS)

    Kerr, George D.; Young, Rebert W.; Cullings, Harry M.; Christry, Robert F.

    2005-01-01

    The reconstruction of neutron and gamma-ray doses at Hiroshima and Nagasaki begins with a determination of the parameters describing the explosion. The calculations of the air transported radiation fields and survivor doses from the Hiroshima and Nagasaki bombs require knowledge of a variety of parameters related to the explosions. These various parameters include the heading of the bomber when the bomb was released, the epicenters of the explosions, the bomb yields, and the tilt of the bombs at time of explosion. The epicenter of a bomb is the explosion point in air that is specified in terms of a burst height and a hypocenter (or the point on the ground directly below the epicenter of the explosion). The current reassessment refines the energy yield and burst height for the Hiroshima bomb, as well as the locations of the Hiroshima and Nagasaki hypocenters on the modern city maps used in the analysis of the activation data for neutrons and TLD data for gamma rays. (J.P.N.)

  1. Electroweak interaction parameters

    International Nuclear Information System (INIS)

    Marciano, W.J.

    1984-01-01

    After a presentation of the experimentally determined parameters of the standard SU(3) x SU(2) x U(1) model the author discusses the definition of the Weinberg angle. Then masses and widths of the intermediate vector bosons are considered in the framework of the Weinberg-Salam theory with radiative corrections. Furthermore the radiative decays of these bosons are discussed. Then the relations between the masses of the Higgs boson and the top quark are considered. Thereafter grand unification is briefly discussed with special regards to the SU(5) prediction of some observable parameters. Finally some speculations are made concerning the observation of radiative decays in the UA1 experiments. (HSI)

  2. 16 CFR 1702.9 - Relevant experimental data.

    Science.gov (United States)

    2010-01-01

    ..., weight, sex and nutritional state of animals; (iii) Dosage level(s) and number of animals tested per... determined LD50 values. (4) In view of the fact that LD50 values in themselves do not necessarily reflect a... published work is submitted. (6) Acute toxicity studies submitted with petitions should have at least a...

  3. Long Pentraxin 3: Experimental and Clinical Relevance in Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Fabrizia Bonacina

    2013-01-01

    Full Text Available Pentraxin 3 (PTX3 is an essential component of the humoral arm of innate immunity and belongs, together with the C-reactive protein (CRP and other acute phase proteins, to the pentraxins' superfamily: soluble, multifunctional, pattern recognition proteins. Pentraxins share a common C-terminal pentraxin domain, which in the case of PTX3 is coupled to an unrelated long N-terminal domain. PTX3 in humans, like CRP, correlates with surrogate markers of atherosclerosis and is independently associated with the risk of developing vascular events. Studies addressing the potential physiopathological role of CRP in the cardiovascular system were so far inconclusive and have been limited by the fact that the sequence and regulation have not been conserved during evolution between mouse and man. On the contrary, the conservation of sequence, gene organization, and regulation of PTX3 supports the translation of animal model findings in humans. While PTX3 deficiency is associated with increased inflammation, cardiac damage, and atherosclerosis, the overexpression limits carotid restenosis after angioplasty. These observations point to a cardiovascular protective effect of PTX3 potentially associated with the ability of tuning inflammation and favor the hypothesis that the increased levels of PTX3 in subjects with cardiovascular diseases may reflect a protective physiological mechanism, which correlates with the immunoinflammatory response observed in several cardiovascular disorders.

  4. Relevance of experimental animal studies to the human experience

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1982-01-01

    Animal experiments are being used to examine a number of physical and biological factors that influence risk estimations though not usually in coordination with epidemiologists. It is clear that the different mechanisms involved in different types of tumors are reflected in the diversity of dose-response relationships. The forms of the dose-response relationships are influenced by both the initial events and their expression. Evidence is accumulating that many initiated cells do not get expressed as overt cancers and host factors may play a major role in the expression of potential tumor cells. There is a need for information about the relationship of the natural incidence and susceptibility to radiation induction for more tumor types. Such experiments will help answer the question of which risk estimate models are appropriate for different tumor types and can be carried out on animals. Perhaps because of the importance of host factors risk estimates as a percentage of the natural incidence appear to be similar for human beings and mice for a small number of tumor types. The elucidation of the mechanisms involved in different tissues while a slow business remains an important role of animal experiments

  5. Experimental investigation on the influence of instrument settings on pixel size and nonlinearity in SEM image formation

    DEFF Research Database (Denmark)

    Carli, Lorenzo; Genta, Gianfranco; Cantatore, Angela

    2010-01-01

    The work deals with an experimental investigation on the influence of three Scanning Electron Microscope (SEM) instrument settings, accelerating voltage, spot size and magnification, on the image formation process. Pixel size and nonlinearity were chosen as output parameters related to image...... quality and resolution. A silicon grating calibrated artifact was employed to investigate qualitatively and quantitatively, through a designed experiment approach, the parameters relevance. SEM magnification was found to account by far for the largest contribution on both parameters under consideration...

  6. Is QCD relevant to nuclear physics

    International Nuclear Information System (INIS)

    Thomas, A.W.

    1985-01-01

    A review is given of recent work on baryon structure in a number of QCD-motivated models. After establishing a prima facie case that the quark model should be relevant in a consistent description of the nucleus over a wide range of momentum transfer, the author looks for experimental confirmation. The discussion includes the search for exotic states, for a six quark component of the deuteron, and an up to date report on the interpretation of the EMC effect. (Auth.)

  7. Hydrogen interaction with fusion-relevant materials

    International Nuclear Information System (INIS)

    Caorlin, M.

    1990-01-01

    This paper is an outline of the work carried out at JRC Ispra in the Tritium-materials Interaction Laboratory, on the interaction of gaseous hydrogen with several materials of interest in the field of fusion technology. Experimental work is reported and a concise review of relevant theoretical and numerical supporting activity is given as well. A period of about seven years is covered since 1982. Current work and possible future extensions are also briefly mentioned. 11 figs., 18 refs

  8. LMFBR plant parameters

    International Nuclear Information System (INIS)

    1979-03-01

    This document contains up-to-date data on existing or firmly decided prototype or demonstration LMFBR reactors (Table I), on planned commercial size LMFBR according to the present status of design (Table II) and on experimental fast reactors such as BOR-60, DFR, EBR-II, FERMI, FFTF, JOYO, KNK-II, PEC, RAPSODIE-FORTISSIMO (Table III). Only corrected and revised parameters submitted by the countries participating in the IWGFR are included in this document

  9. HF Parameters of Induction Motor

    Directory of Open Access Journals (Sweden)

    M. N. Benallal

    2017-09-01

    Full Text Available This article describes the results of experimental studies of HF input and primary parameters. A simulation model in Matlab SimulinkTM of multiphase windings as ladder circuit of coils is developed. A method for determining the primary parameters of ladder equivalent circuits is presented.

  10. Experimental First Order Pairing Phase Transition in Atomic Nuclei

    International Nuclear Information System (INIS)

    Moretto, L G; Larsen, A C; Giacoppo, F; Guttormsen, M; Siem, S

    2015-01-01

    The natural log of experimental nuclear level densities at low energy is linear with energy. This can be interpreted in terms of a nearly 1st order phase transition from a superfluid to an ideal gas of quasi particles. The transition temperature coincides with the BCS critical temperature and yields gap parameters in good agreement with the values extracted from even- odd mass differences from rotational states. This converging evidence supports the relevance of the BCS theory to atomic nuclei

  11. Inferring relevance in a changing world

    Directory of Open Access Journals (Sweden)

    Robert C Wilson

    2012-01-01

    Full Text Available Reinforcement learning models of human and animal learning usually concentrate on how we learn the relationship between different stimuli or actions and rewards. However, in real world situations stimuli are ill-defined. On the one hand, our immediate environment is extremely multi-dimensional. On the other hand, in every decision-making scenario only a few aspects of the environment are relevant for obtaining reward, while most are irrelevant. Thus a key question is how do we learn these relevant dimensions, that is, how do we learn what to learn about? We investigated this process of representation learning experimentally, using a task in which one stimulus dimension was relevant for determining reward at each point in time. As in real life situations, in our task the relevant dimension can change without warning, adding ever-present uncertainty engendered by a constantly changing environment. We show that human performance on this task is better described by a suboptimal strategy based on selective attention and serial hypothesis testing rather than a normative strategy based on probabilistic inference. From this, we conjecture that the problem of inferring relevance in general scenarios is too computationally demanding for the brain to solve optimally. As a result the brain utilizes approximations, employing these even in simplified scenarios in which optimal representation learning is tractable, such as the one in our experiment.

  12. Animal experimentation.

    Science.gov (United States)

    Kolar, Roman

    2006-01-01

    Millions of animals are used every year in often times extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the "3Rs" concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, often times undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees' members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation.

  13. Transesophageal NOTES--a critical analysis of relevant problems.

    Science.gov (United States)

    Grund, Karl E; Lehmann, Thorsten G

    2010-10-01

    The transesophageal access route has not become a principal topic in the discussion about NOTES up to now. Analyzing the problems in this new field of surgery, however, the transesophageal route shows high relevance. Here, all possibilities, limitations, and problems of NOTES become obvious. This paper contains a critical analysis of the literature published to date (nine full papers, five abstracts). Nearly all publications represent experimental studies in living pigs. In most cases a submucosal tunnel technique is performed as access route to mediastinum, pleural cavity, and heart. Interventions and operations include simple mediastinoscopies as well as epicardial operations after exposition of the heart. For access and manipulation, conventional flexible endoscopes and instruments are used. Clips, T-bars, or a combination of both achieve the closure. Some studies rely on spontaneous closure of the incision without any suturing or approximation. In such experimental settings, the following results are presented: Access is achieved in 90% of cases, the aim of the operation is met in 92%, technical success in closure is achieved in 90%, healing of incision assessed as good in two of five studies, satisfactory in three of five studies. Mortality, ranging from 6 to 25%, and complication rates were (surprisingly) high. It has to be stressed that analyzing these papers published to date, no adequate attention is paid to basic facts and problems of general and thoracic surgery (e.g. different forms, prevention, diagnosis and therapy of pneumothorax or differentiated forms of ventilation). Relevant differences in the anatomy and physiology of the esophagus and mediastinum between humans and pigs should additionally be taken into account to choose optimal experimental parameters when transferring results to human settings. Moreover, requirements regarding sterility and hygiene in a structure like the mediastinum, which is at high risk from the point of view of infection

  14. Environmentally relevant approaches to assess nanoparticles ecotoxicity: A review

    Energy Technology Data Exchange (ETDEWEB)

    Bour, Agathe; Mouchet, Florence; Silvestre, Jérôme; Gauthier, Laury [Université de Toulouse (France); UPS, INP (France); EcoLab (Laboratoire d’écologie fonctionnelle et environnement) (France); ENSAT, Avenue de l’Agrobiopôle, F-31326 Castanet-Tolosan (France); CNRS (France); EcoLab (Laboratoire d’écologie fonctionnelle et environnement), F-31326 Castanet-Tolosan (France); Pinelli, Eric, E-mail: pinelli@ensat.fr [Université de Toulouse (France); UPS, INP (France); EcoLab (Laboratoire d’écologie fonctionnelle et environnement) (France); ENSAT, Avenue de l’Agrobiopôle, F-31326 Castanet-Tolosan (France); CNRS (France); EcoLab (Laboratoire d’écologie fonctionnelle et environnement), F-31326 Castanet-Tolosan (France)

    2015-02-11

    Highlights: • Integrated ecotoxicity of NPs from organism to community level is reviewed. • Trophic chains allow determining the implication of trophic route in NP toxicity. • The use of microcosms and mesocosms allows studies at larger scale. • Data concerning NP fate and effects in environmental conditions are lacking. - Abstract: Despite the increasing production and use of nanoparticles (NPs), there is a lack of knowledge about their environmental fate and ecotoxicity. Studies in environmentally relevant conditions are necessary to better assess these parameters, but such studies are rather rare. The present work represents first time that studies on engineered NPs using environmentally relevant exposure methods have been reviewed. These exposure methods differ from standardized protocols and can be classified into three groups: experimental trophic chains that allow study of the trophic route, multi-species exposures under laboratory conditions that allow for complex but controlled exposure and outdoor exposures that are more similar to environmentally realistic conditions. The majority of studies of micro- or mesocosms have focused on NP partitioning and bioaccumulation. The other major parameter that has been studied is NP ecotoxicity, which has been assessed in single species, in single species via the trophic route, and at the community level. The induction of biochemical defense systems, immunomodulation, effects on growth and reproduction, behavioral alterations and mortality have been used as indicators of major toxicity, depending on the species studied. The major effects of NPs on both microbial and algal communities include modifications of community compositions and diversities, decreased biomass and changes in community activities.

  15. Environmentally relevant approaches to assess nanoparticles ecotoxicity: A review

    International Nuclear Information System (INIS)

    Bour, Agathe; Mouchet, Florence; Silvestre, Jérôme; Gauthier, Laury; Pinelli, Eric

    2015-01-01

    Highlights: • Integrated ecotoxicity of NPs from organism to community level is reviewed. • Trophic chains allow determining the implication of trophic route in NP toxicity. • The use of microcosms and mesocosms allows studies at larger scale. • Data concerning NP fate and effects in environmental conditions are lacking. - Abstract: Despite the increasing production and use of nanoparticles (NPs), there is a lack of knowledge about their environmental fate and ecotoxicity. Studies in environmentally relevant conditions are necessary to better assess these parameters, but such studies are rather rare. The present work represents first time that studies on engineered NPs using environmentally relevant exposure methods have been reviewed. These exposure methods differ from standardized protocols and can be classified into three groups: experimental trophic chains that allow study of the trophic route, multi-species exposures under laboratory conditions that allow for complex but controlled exposure and outdoor exposures that are more similar to environmentally realistic conditions. The majority of studies of micro- or mesocosms have focused on NP partitioning and bioaccumulation. The other major parameter that has been studied is NP ecotoxicity, which has been assessed in single species, in single species via the trophic route, and at the community level. The induction of biochemical defense systems, immunomodulation, effects on growth and reproduction, behavioral alterations and mortality have been used as indicators of major toxicity, depending on the species studied. The major effects of NPs on both microbial and algal communities include modifications of community compositions and diversities, decreased biomass and changes in community activities

  16. Progress of LMJ-relevant implosions experiments on OMEGA

    Directory of Open Access Journals (Sweden)

    Casner A.

    2013-11-01

    Full Text Available In preparation of the first ignition attempts on the Laser Mégajoule (LMJ, an experimental program is being pursued on OMEGA to investigate LMJ-relevant hohlraums. First, radiation temperature levels close to 300 eV were recently achieved in reduced-scale hohlraums with modest backscatter losses. Regarding the baseline target design for fusion experiments on LMJ, an extensive experimental database has also been collected for scaled implosions experiments in both empty and gas-filled rugby-shaped hohlraums. We acquired a full picture of hohlraum energetics and implosion dynamics. Not only did the rugby hohlraums show significantly higher x-ray drive energy over the cylindrical hohlraums, but symmetry control by power balance was demonstrated, as well as high-performance D2 implosions enabling the use of a complete suite of neutrons diagnostics. Charged particle diagnostics provide complementary insights into the physics of these x-ray driven implosions. An overview of these results demonstrates our ability to control the key parameters driving the implosion, lending more confidence in extrapolations to ignition-scale targets.

  17. WIPP Compliance Certification Application calculations parameters. Part 1: Parameter development

    International Nuclear Information System (INIS)

    Howarth, S.M.

    1997-01-01

    The Waste Isolation Pilot Plant (WIPP) in southeast New Mexico has been studied as a transuranic waste repository for the past 23 years. During this time, an extensive site characterization, design, construction, and experimental program was completed, which provided in-depth understanding of the dominant processes that are most likely to influence the containment of radionuclides for 10,000 years. Nearly 1,500 parameters were developed using information gathered from this program; the parameters were input to numerical models for WIPP Compliance Certification Application (CCA) Performance Assessment (PA) calculations. The CCA probabilistic codes frequently require input values that define a statistical distribution for each parameter. Developing parameter distributions begins with the assignment of an appropriate distribution type, which is dependent on the type, magnitude, and volume of data or information available. The development of the parameter distribution values may require interpretation or statistical analysis of raw data, combining raw data with literature values, scaling of lab or field data to fit code grid mesh sizes, or other transformation. Parameter development and documentation of the development process were very complicated, especially for those parameters based on empirical data; they required the integration of information from Sandia National Laboratories (SNL) code sponsors, parameter task leaders (PTLs), performance assessment analysts (PAAs), and experimental principal investigators (PIs). This paper, Part 1 of two parts, contains a discussion of the parameter development process, roles and responsibilities, and lessons learned. Part 2 will discuss parameter documentation, traceability and retrievability, and lessons learned from related audits and reviews

  18. Physiological parameters

    International Nuclear Information System (INIS)

    Natera, E.S.

    1998-01-01

    The physiological characteristics of man depend on the intake, metabolism and excretion of stable elements from food, water, and air. The physiological behavior of natural radionuclides and radionuclides from nuclear weapons testing and from the utilization of nuclear energy is believed to follow the pattern of stable elements. Hence information on the normal physiological processes occurring in the human body plays an important role in the assessment of the radiation dose received by man. Two important physiological parameters needed for internal dose determination are the pulmonary function and the water balance. In the Coordinated Research Programme on the characterization of Asian population, five participants submitted data on these physiological characteristics - China, India, Japan, Philippines and Viet Nam. During the CRP, data on other pertinent characteristics such as physical and dietary were simultaneously being collected. Hence, the information on the physiological characteristics alone, coming from the five participants were not complete and are probably not sufficient to establish standard values for the Reference Asian Man. Nonetheless, the data collected is a valuable contribution to this research programme

  19. Material parameter identification and inverse problems in soft tissue biomechanics

    CERN Document Server

    Evans, Sam

    2017-01-01

    The articles in this book review hybrid experimental-computational methods applied to soft tissues which have been developed by worldwide specialists in the field. People developing computational models of soft tissues and organs will find solutions for calibrating the material parameters of their models; people performing tests on soft tissues will learn what to extract from the data and how to use these data for their models and people worried about the complexity of the biomechanical behavior of soft tissues will find relevant approaches to address this complexity.

  20. Pulsatility Index as a Diagnostic Parameter of Reciprocating Wall Shear Stress Parameters in Physiological Pulsating Waveforms.

    Directory of Open Access Journals (Sweden)

    Idit Avrahami

    Full Text Available Arterial wall shear stress (WSS parameters are widely used for prediction of the initiation and development of atherosclerosis and arterial pathologies. Traditional clinical evaluation of arterial condition relies on correlations of WSS parameters with average flow rate (Q and heart rate (HR measurements. We show that for pulsating flow waveforms in a straight tube with flow reversals that lead to significant reciprocating WSS, the measurements of HR and Q are not sufficient for prediction of WSS parameters. Therefore, we suggest adding a third quantity-known as the pulsatility index (PI-which is defined as the peak-to-peak flow rate amplitude normalized by Q. We examine several pulsating flow waveforms with and without flow reversals using a simulation of a Womersley model in a straight rigid tube and validate the simulations through experimental study using particle image velocimetry (PIV. The results indicate that clinically relevant WSS parameters such as the percentage of negative WSS (P[%], oscillating shear index (OSI and the ratio of minimum to maximum shear stress rates (min/max, are better predicted when the PI is used in conjunction with HR and Q. Therefore, we propose to use PI as an additional and essential diagnostic quantity for improved predictability of the reciprocating WSS.

  1. Evaluating automatic attentional capture by self-relevant information.

    Science.gov (United States)

    Ocampo, Brenda; Kahan, Todd A

    2016-01-01

    Our everyday decisions and memories are inadvertently influenced by self-relevant information. For example, we are faster and more accurate at making perceptual judgments about stimuli associated with ourselves, such as our own face or name, as compared with familiar non-self-relevant stimuli. Humphreys and Sui propose a "self-attention network" to account for these effects, wherein self-relevant stimuli automatically capture our attention and subsequently enhance the perceptual processing of self-relevant information. We propose that the masked priming paradigm and continuous flash suppression represent two ways to experimentally examine these controversial claims.

  2. Increasing process understanding by analyzing complex interactions in experimental data

    DEFF Research Database (Denmark)

    Naelapaa, Kaisa; Allesø, Morten; Kristensen, Henning Gjelstrup

    2009-01-01

    understanding of a coating process. It was possible to model the response, that is, the amount of drug released, using both mentioned techniques. However, the ANOVAmodel was difficult to interpret as several interactions between process parameters existed. In contrast to ANOVA, GEMANOVA is especially suited...... for modeling complex interactions and making easily understandable models of these. GEMANOVA modeling allowed a simple visualization of the entire experimental space. Furthermore, information was obtained on how relative changes in the settings of process parameters influence the film quality and thereby drug......There is a recognized need for new approaches to understand unit operations with pharmaceutical relevance. A method for analyzing complex interactions in experimental data is introduced. Higher-order interactions do exist between process parameters, which complicate the interpretation...

  3. Infecção experimental em suínos jovens com Leptospira interrogans sorovar wolffi: determinação de parâmetros bioquímicos Experimental infection by Leptospira interrogans serovar wolffi in young pigs: determination of biochemical parameters

    Directory of Open Access Journals (Sweden)

    José Carlos Rende

    2007-04-01

    were inoculated by the same way with 5.0mL of a cell culture containing 1.0x10(8cells/mL of Leptospira interrogans sorovar wolffi, wild strain L-10, isolated from a wild especies of brazilian "armadillo" (Dasypus novemcinctus. Three days after inoculation, blood was collected without anticoagulant; the same process was repeated at 72 hours intervals during eighteen days in both, control and experimental groups. Quantitative biochemical parameters were direct, indirect and total bilirubin, fatty acids and serum proteins. The experimental animals showed an increase of direct bilirubin three days after inoculation. Increases in indirect and total bilirubin were, also, observed after six days. Glucose, fatty acids and serum proteins decreased after the third day of inoculation. In conclusion, the increase in bilirubin levels could be due to acute hemolysis; hypoglycemia, hypolipidemia and hypoproteinemia that could be related to hepatic lesions and septicemia. All parameters returned to normal levels after fifteen days, in all animals tested.

  4. Optomechanical parameter estimation

    International Nuclear Information System (INIS)

    Ang, Shan Zheng; Tsang, Mankei; Harris, Glen I; Bowen, Warwick P

    2013-01-01

    We propose a statistical framework for the problem of parameter estimation from a noisy optomechanical system. The Cramér–Rao lower bound on the estimation errors in the long-time limit is derived and compared with the errors of radiometer and expectation–maximization (EM) algorithms in the estimation of the force noise power. When applied to experimental data, the EM estimator is found to have the lowest error and follow the Cramér–Rao bound most closely. Our analytic results are envisioned to be valuable to optomechanical experiment design, while the EM algorithm, with its ability to estimate most of the system parameters, is envisioned to be useful for optomechanical sensing, atomic magnetometry and fundamental tests of quantum mechanics. (paper)

  5. Profiles of Dialogue for Relevance

    Directory of Open Access Journals (Sweden)

    Douglas Walton

    2016-12-01

    Full Text Available This paper uses argument diagrams, argumentation schemes, and some tools from formal argumentation systems developed in artificial intelligence to build a graph-theoretic model of relevance shown to be applicable (with some extensions as a practical method for helping a third party judge issues of relevance or irrelevance of an argument in real examples. Examples used to illustrate how the method works are drawn from disputes about relevance in natural language discourse, including a criminal trial and a parliamentary debate.

  6. Efficient classification of complete parameter regions based on semidefinite programming

    Directory of Open Access Journals (Sweden)

    Parrilo Pablo A

    2007-01-01

    Full Text Available Abstract Background Current approaches to parameter estimation are often inappropriate or inconvenient for the modelling of complex biological systems. For systems described by nonlinear equations, the conventional approach is to first numerically integrate the model, and then, in a second a posteriori step, check for consistency with experimental constraints. Hence, only single parameter sets can be considered at a time. Consequently, it is impossible to conclude that the "best" solution was identified or that no good solution exists, because parameter spaces typically cannot be explored in a reasonable amount of time. Results We introduce a novel approach based on semidefinite programming to directly identify consistent steady state concentrations for systems consisting of mass action kinetics, i.e., polynomial equations and inequality constraints. The duality properties of semidefinite programming allow to rigorously certify infeasibility for whole regions of parameter space, thus enabling the simultaneous multi-dimensional analysis of entire parameter sets. Conclusion Our algorithm reduces the computational effort of parameter estimation by several orders of magnitude, as illustrated through conceptual sample problems. Of particular relevance for systems biology, the approach can discriminate between structurally different candidate models by proving inconsistency with the available data.

  7. Modelling low energy electron and positron tracks in biologically relevant media

    International Nuclear Information System (INIS)

    Blanco, F.; Munoz, A.; Almeida, D.; Ferreira da Silva, F.; Limao-Vieira, P.; Fuss, M.C.; Sanz, A.G.; Garcia, G.

    2013-01-01

    This colloquium describes an approach to incorporate into radiation damage models the effect of low and intermediate energy (0-100 eV) electrons and positrons, slowing down in biologically relevant materials (water and representative biomolecules). The core of the modelling procedure is a C++ computing programme named 'Low Energy Particle Track Simulation (LEPTS)', which is compatible with available general purpose Monte Carlo packages. Input parameters are carefully selected from theoretical and experimental cross section data and energy loss distribution functions. Data sources used for this purpose are reviewed showing examples of electron and positron cross section and energy loss data for interactions with different media of increasing complexity: atoms, molecules, clusters and condense matter. Finally, we show how such a model can be used to develop an effective dosimetric tool at the molecular level (i.e. nanodosimetry). Recent experimental developments to study the fragmentation induced in biologically material by charge transfer from neutrals and negative ions are also included. (authors)

  8. Relevance theory: pragmatics and cognition.

    Science.gov (United States)

    Wearing, Catherine J

    2015-01-01

    Relevance Theory is a cognitively oriented theory of pragmatics, i.e., a theory of language use. It builds on the seminal work of H.P. Grice(1) to develop a pragmatic theory which is at once philosophically sensitive and empirically plausible (in both psychological and evolutionary terms). This entry reviews the central commitments and chief contributions of Relevance Theory, including its Gricean commitment to the centrality of intention-reading and inference in communication; the cognitively grounded notion of relevance which provides the mechanism for explaining pragmatic interpretation as an intention-driven, inferential process; and several key applications of the theory (lexical pragmatics, metaphor and irony, procedural meaning). Relevance Theory is an important contribution to our understanding of the pragmatics of communication. © 2014 John Wiley & Sons, Ltd.

  9. Uncertainties of Molecular Structural Parameters

    International Nuclear Information System (INIS)

    Császár, Attila G.

    2014-01-01

    performed. Simply, there are significant disagreements between the same bond lengths measured by different techniques. These disagreements are, however, systematic and can be computed via techniques of quantum chemistry which deal not only with the motions of the electrons (electronic structure theory) but also with the often large amplitude motions of the nuclei. As to the relevant quantum chemical computations, since about 1970 electronic structure theory has become able to make quantitative predictions and thus challenge (or even overrule) many experiments. Nevertheless, quantitative agreement of quantum chemical results with experiment can only be expected when the motions of the atoms are also considered. In the fourth age of quantum chemistry we are living in an era where one can bridge quantitatively the gap between ‘effective’, experimental and ‘equilibrium’, computed structures at even elevated temperatures of interest thus minimizing any real uncertainties of structural parameters. The connections mentioned are extremely important as they help to understand the true uncertainty of measured structural parameters. Traditionally it is microwave (MW) and millimeterwave (MMW) spectroscopy, as well as gas-phase electron diffraction (GED), which yielded the most accurate structural parameters of molecules. The accuracy of the MW and GED experiments approached about 0.001Å and 0.1º under ideal circumstances, worse, sometimes considerably worse, in less than ideal and much more often encountered situations. Quantum chemistry can define both highly accurate equilibrium (so-called Born-Oppenheimer, r_e"B"O, and semiexperimental, r_e"S"E) structures and, via detailed investigation of molecular motions, accurate temperature-dependent rovibrationally averaged structures. Determining structures is still a rich field for research, understanding the measured or computed uncertainties of structures and structural parameters is still a challenge but there are firm and well

  10. Clinical relevance in anesthesia journals

    DEFF Research Database (Denmark)

    Lauritsen, Jakob; Møller, Ann M

    2006-01-01

    The purpose of this review is to present the latest knowledge and research on the definition and distribution of clinically relevant articles in anesthesia journals. It will also discuss the importance of the chosen methodology and outcome of articles.......The purpose of this review is to present the latest knowledge and research on the definition and distribution of clinically relevant articles in anesthesia journals. It will also discuss the importance of the chosen methodology and outcome of articles....

  11. Feasibility of a single-parameter description of equilibrium viscous liquid dynamics

    DEFF Research Database (Denmark)

    Pedersen, Ulf Rørbæk; Christensen, Tage Emil; Schrøder, Thomas

    2008-01-01

    Molecular dynamics results for the dynamic Prigogine-Defay ratio are presented for two glass-forming liquids, thus evaluating the experimentally relevant quantity for testing whether metastable-equilibrium liquid dynamics is described by a single parameter to a good approximation. For the Kob......-Andersen binary Lennard-Jones mixture as well as for an asymmetric dumbbell model liquid, a single-parameter description works quite well. This is confirmed by time-domain results where it is found that energy and pressure fluctuations are strongly correlated on the alpha time scale in the constant...

  12. DETERMINATION OF RELEVANT FEATURES OF A SCALE MODEL FOR A 55 000 DWT BULK CARRIER NECESSARY TO STUDY THE SHIP MANEUVERABILITY

    Directory of Open Access Journals (Sweden)

    ALECU TOMA

    2016-06-01

    Full Text Available The study method of a ship behavior based on practical tests on scale models is widely used both leading scientists and engineers, architects and researchers in the naval field. In this paper we propose to determine the parameters of a ship handling characteristics relevant to study the 55,000 dwt bulk carrier using a scale model. Scientific background for practical experimentation of this techniques necessary to built a scale model ship consists in applying the principles of similarity or "similitude". The scale model achieved by applying the laws of similarity must allow, through approximations available in certain circumstances, finding relevant parameters needed to simplify and solve the Navier-Stokes equations. These parameters are necessary for modeling the interaction between hull of the real ship and the fluid motion.

  13. Optimization of parameters of heat exchangers vehicles

    Directory of Open Access Journals (Sweden)

    Andrei MELEKHIN

    2014-09-01

    Full Text Available The relevance of the topic due to the decision of problems of the economy of resources in heating systems of vehicles. To solve this problem we have developed an integrated method of research, which allows to solve tasks on optimization of parameters of heat exchangers vehicles. This method decides multicriteria optimization problem with the program nonlinear optimization on the basis of software with the introduction of an array of temperatures obtained using thermography. The authors have developed a mathematical model of process of heat exchange in heat exchange surfaces of apparatuses with the solution of multicriteria optimization problem and check its adequacy to the experimental stand in the visualization of thermal fields, an optimal range of managed parameters influencing the process of heat exchange with minimal metal consumption and the maximum heat output fin heat exchanger, the regularities of heat exchange process with getting generalizing dependencies distribution of temperature on the heat-release surface of the heat exchanger vehicles, defined convergence of the results of research in the calculation on the basis of theoretical dependencies and solving mathematical model.

  14. Process Damping Parameters

    International Nuclear Information System (INIS)

    Turner, Sam

    2011-01-01

    The phenomenon of process damping as a stabilising effect in milling has been encountered by machinists since milling and turning began. It is of great importance when milling aerospace alloys where maximum surface speed is limited by excessive tool wear and high speed stability lobes cannot be attained. Much of the established research into regenerative chatter and chatter avoidance has focussed on stability lobe theory with different analytical and time domain models developed to expand on the theory first developed by Trusty and Tobias. Process damping is a stabilising effect that occurs when the surface speed is low relative to the dominant natural frequency of the system and has been less successfully modelled and understood. Process damping is believed to be influenced by the interference of the relief face of the cutting tool with the waveform traced on the cut surface, with material properties and the relief geometry of the tool believed to be key factors governing performance. This study combines experimental trials with Finite Element (FE) simulation in an attempt to identify and understand the key factors influencing process damping performance in titanium milling. Rake angle, relief angle and chip thickness are the variables considered experimentally with the FE study looking at average radial and tangential forces and surface compressive stress. For the experimental study a technique is developed to identify the critical process damping wavelength as a means of measuring process damping performance. For the range of parameters studied, chip thickness is found to be the dominant factor with maximum stable parameters increased by a factor of 17 in the best case. Within the range studied, relief angle was found to have a lesser effect than expected whilst rake angle had an influence.

  15. LMFBR plant parameters 1991

    International Nuclear Information System (INIS)

    1991-03-01

    The document has been prepared on the basis of information provided by the members of the IAEA International Working Group on Fast Reactors (IWGFR). It contains updated parameters of 27 experimental, prototype and commercial size liquid metal fast breeder reactors (LMFBRs). Most of the reactors are currently in operation, under construction or in an advanced planning stage. Parameters of the Clinch River Breeder Reactor (USA), PEC (Italy), RAPSODIE (France), DFR (UK) and EFFBR (USA) are included in the report because of their important role in the development of LMFBR technology from first LMFBRs to the prototype size fast reactors. Two more reactors appeared in the list: European Fast Reactor (EFR) and PRISM (USA). Parameters of these reactors included in this publication are based on the data from the papers presented at the 23rd Annual Meeting of the IWGFR. All in all more than four hundred corrections and additions have been made to update the document. The report is intended for specialists and institutions in industrialized and developing countries who are responsible for the design and operation of liquid metal fast breeder reactors

  16. Shippingport: A relevant decommissioning project

    International Nuclear Information System (INIS)

    Crimi, F.P.

    1988-01-01

    Because of Shippingport's low electrical power rating (72 MWe), there has been some misunderstanding on the relevancy of the Shippingport Station Decommissioning Project (SSDP) to a modern 1175 MWe commercial pressurized water reactor (PWR) power station. This paper provides a comparison of the major components of the reactor plant of the 72 MWe Shippingport Atomic Power Station and an 1175 MWe nuclear plant and the relevancy of the Shippingport decommissioning as a demonstration project for the nuclear industry. For the purpose of this comparison, Portland General Electric Company's 1175 MWe Trojan Nuclear Plant at Rainier, Oregon, has been used as the reference nuclear power plant. 2 refs., 2 figs., 1 tab

  17. Qualitative Parameters of Practice during University Studies

    Science.gov (United States)

    Stasiunaitiene, Egle; Norkute, Odeta

    2011-01-01

    In this article, relevance of practice during university studies is highlighted, as well as the main stages of its organisation, qualitative parameters, as well as criteria and indicators that validate them are defined. Discussion on the idea that taking into consideration qualitative parameters of organising practice as a component of studies…

  18. Electro-optical parameters of bond polarizability model for aluminosilicates.

    Science.gov (United States)

    Smirnov, Konstantin S; Bougeard, Daniel; Tandon, Poonam

    2006-04-06

    Electro-optical parameters (EOPs) of bond polarizability model (BPM) for aluminosilicate structures were derived from quantum-chemical DFT calculations of molecular models. The tensor of molecular polarizability and the derivatives of the tensor with respect to the bond length are well reproduced with the BPM, and the EOPs obtained are in a fair agreement with available experimental data. The parameters derived were found to be transferable to larger molecules. This finding suggests that the procedure used can be applied to systems with partially ionic chemical bonds. The transferability of the parameters to periodic systems was tested in molecular dynamics simulation of the polarized Raman spectra of alpha-quartz. It appeared that the molecular Si-O bond EOPs failed to reproduce the intensity of peaks in the spectra. This limitation is due to large values of the longitudinal components of the bond polarizability and its derivative found in the molecular calculations as compared to those obtained from periodic DFT calculations of crystalline silica polymorphs by Umari et al. (Phys. Rev. B 2001, 63, 094305). It is supposed that the electric field of the solid is responsible for the difference of the parameters. Nevertheless, the EOPs obtained can be used as an initial set of parameters for calculations of polarizability related characteristics of relevant systems in the framework of BPM.

  19. Dramatic lives and relevant becomings

    DEFF Research Database (Denmark)

    Henriksen, Ann-Karina; Miller, Jody

    2012-01-01

    of marginality into positions of relevance. The analysis builds on empirical data from Copenhagen, Denmark, gained through ethnographic fieldwork with the participation of 20 female informants aged 13–22. The theoretical contribution proposes viewing conflicts as multi-linear, multi-causal and non...

  20. Regularization in Matrix Relevance Learning

    NARCIS (Netherlands)

    Schneider, Petra; Bunte, Kerstin; Stiekema, Han; Hammer, Barbara; Villmann, Thomas; Biehl, Michael

    A In this paper, we present a regularization technique to extend recently proposed matrix learning schemes in learning vector quantization (LVQ). These learning algorithms extend the concept of adaptive distance measures in LVQ to the use of relevance matrices. In general, metric learning can

  1. Experimental investigation of the EPR parameters and molecular orbital bonding coefficients for VO{sup 2+} ion in NaH{sub 2}PO{sub 4}·2H{sub 2}O single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kalfaoğlu, Emel [Ondokuz Mayıs University, Faculty of Sciences, Department of Physics, 55139 Kurupelit-Samsun (Turkey); Karabulut, Bünyamin, E-mail: bbulut@omu.edu.tr [Ondokuz Mayıs University, Faculty of Engineering, Department of Computer Engineering, 55139 Kurupelit-Samsun (Turkey)

    2016-09-15

    Electron paramagnetic resonance (EPR) spectra of VO{sup 2+} ions in NaH{sub 2}PO{sub 4}·2H{sub 2}O single crystal have been studied. The spin-Hamiltonian parameters and molecular orbital bonding coefficients were calculated. The angular variation of the EPR spectra shows two different VO{sup 2+} complexes. These are located in different chemical environment and each environment contains four magnetically inequivalent VO{sup 2+} sites. The crystal field around VO{sup 2+} ion is approximately axially symmetric since a strong V=O bond distorts the crystal lattice. Spin Hamiltonian parameters and molecular orbital bonding coefficients were calculated from the EPR data and the nature of bonding in the complex was discussed together.

  2. Fitter. The package for fitting a chosen theoretical multi-parameter function through a set of data points. Application to experimental data of the YuMO spectrometer. Version 2.1.0. Long write-up and user's guide

    International Nuclear Information System (INIS)

    Solov'ev, A.G.; Stadnik, A.V.; Islamov, A.N.; Kuklin, A.I.

    2008-01-01

    Fitter is a C++ program aimed to fit a chosen theoretical multi-parameter function through a set of data points. The method of fitting is chi-square minimization. Moreover, the robust fitting method can be applied to Fitter. Fitter was designed to be used for a small-angle neutron scattering data analysis. Respective theoretical models are implemented in it. Some commonly used models (Gaussian and polynomials) are also implemented for wider applicability

  3. Parameter identification of an electrically actuated imperfect microbeam

    KAUST Repository

    Ruzziconi, Laura

    2013-12-01

    In this study we consider a microelectromechanical system (MEMS) and focus on extracting analytically the model parameters that describe its non-linear dynamic features accurately. The device consists of a clamped-clamped polysilicon microbeam electrostatically and electrodynamically actuated. The microbeam has imperfections in the geometry, which are related to the microfabrication process, resulting in many unknown and uncertain parameters of the device. The objective of the present paper is to introduce a simple but appropriate model which, despite the inevitable approximations, is able to describe and predict the most relevant aspects of the experimental response in a neighborhood of the first symmetric resonance. The modeling includes the main imperfections in the microstructure. The unknown parameters are settled via parametric identification. The approach is developed in the frequency domain and is based on matching both the frequency values and, remarkably, the frequency response curves, which are considered as the most salient features of the device response. Non-linearities and imperfections considerably complicate the identification process. Via the combined use of linear analysis and non-linear dynamic simulations, a single first symmetric mode reduced-order model is derived. Extensive numerical simulations are performed at increasing values of electrodynamic excitation. Comparison with experimental data shows a satisfactory concurrence of results not only at low electrodynamic voltage, but also at higher ones. This validates the proposed theoretical approach. We highlight its applicability, both in similar case-studies and, more in general, in systems. © 2013 Elsevier Ltd.

  4. varying elastic parameters distributions

    KAUST Repository

    Moussawi, Ali

    2014-12-01

    The experimental identication of mechanical properties is crucial in mechanics for understanding material behavior and for the development of numerical models. Classical identi cation procedures employ standard shaped specimens, assume that the mechanical elds in the object are homogeneous, and recover global properties. Thus, multiple tests are required for full characterization of a heterogeneous object, leading to a time consuming and costly process. The development of non-contact, full- eld measurement techniques from which complex kinematic elds can be recorded has opened the door to a new way of thinking. From the identi cation point of view, suitable methods can be used to process these complex kinematic elds in order to recover multiple spatially varying parameters through one test or a few tests. The requirement is the development of identi cation techniques that can process these complex experimental data. This thesis introduces a novel identi cation technique called the constitutive compatibility method. The key idea is to de ne stresses as compatible with the observed kinematic eld through the chosen class of constitutive equation, making possible the uncoupling of the identi cation of stress from the identi cation of the material parameters. This uncoupling leads to parametrized solutions in cases where 5 the solution is non-unique (due to unknown traction boundary conditions) as demonstrated on 2D numerical examples. First the theory is outlined and the method is demonstrated in 2D applications. Second, the method is implemented within a domain decomposition framework in order to reduce the cost for processing very large problems. Finally, it is extended to 3D numerical examples. Promising results are shown for 2D and 3D problems.

  5. The Improved Relevance Voxel Machine

    DEFF Research Database (Denmark)

    Ganz, Melanie; Sabuncu, Mert; Van Leemput, Koen

    The concept of sparse Bayesian learning has received much attention in the machine learning literature as a means of achieving parsimonious representations of features used in regression and classification. It is an important family of algorithms for sparse signal recovery and compressed sensing....... Hence in its current form it is reminiscent of a greedy forward feature selection algorithm. In this report, we aim to solve the problems of the original RVoxM algorithm in the spirit of [7] (FastRVM).We call the new algorithm Improved Relevance Voxel Machine (IRVoxM). Our contributions...... and enables basis selection from overcomplete dictionaries. One of the trailblazers of Bayesian learning is MacKay who already worked on the topic in his PhD thesis in 1992 [1]. Later on Tipping and Bishop developed the concept of sparse Bayesian learning [2, 3] and Tipping published the Relevance Vector...

  6. Numerical and experimental study of the influence of the operational parameters on the formation mechanisms of oxides of nitrogen during the combustion of mixtures of cellulosic and plastic materials; Etude experimentale et numerique de l'influence des parametres operatoires sur les mecanismes de formation des oxydes d'azote lors de la combustion de melanges de materiaux cellulosiques et plastiques

    Energy Technology Data Exchange (ETDEWEB)

    Andzi Barhe, T.

    2004-10-15

    The current thesis was performed within a collaboration between the Laboratoire de Combustion et de Detonique (LCD of the University of Poitiers) and the Laboratoire de Physique et de Chimie d'Environnement (LPCE) of the University of Ouagadougou. It was financed by Agency for Environment and Energy Management (ADEME). The principle object of this study is the optimisation of the combustion process during the incineration of waste. This optimisation is aimed at the reduction of the polluting emissions, principally CO and NO, during the incineration of cellulosic and plastic materials. It involves the analysis of the influence of the operational parameters on the polluting emissions and the control of reaction mechanisms of formation and reduction of these pollutants during the combustion process. Consequently, the study was performed in two parts: an experimental part and a numerical part. The experimental part was realised using a fixed bed counterflow reactor. This setup simulates the combustion within an industrial waste incinerator. The reactor allows the combustion of a vertical layer of waste mixture (wood, cardboard, PET, polyamide) to be followed. Three model mixtures representative of the makeup of household waste were studied in order to determine the influence of the composition of the waste on the emission of pollutants (CO and NO). The obtained results show that this parameter has a practically negligible influence within the tested parameter range. Consequently the formation of pollutants depends on the operating parameters - the equivalence ratio and the temperature. A numerical study of the influence of these parameters in order to show their impact on the mechanisms of pollutant formation and to determine the chemical mechanisms involved in the formation of oxides of nitrogen. The numerical study was performed with software developed at the LCD. This programme based on a detailed chemical model coupled to a simple physical model. It uses the

  7. LMFBR plant parameters

    International Nuclear Information System (INIS)

    1985-07-01

    This document has been prepared on the basis of information compiled by the members of the IAEA International Working Group on Fast Reactors (IWGFR). It contains parameters of 25 experimental, prototype and commercial size liquid metal fast breeder reactors (LMFBR). Most of the reactors are currently in operation, under construction or in an advanced planning stage. Parameters of the Clinch River Breeder Reactor (USA) are presented because its design was nearly finished and most of the components were fabricated at the time when the project was terminated. Three reactors (RAPSODIE (France), DFR (UK) and EFFBR (USA)) have been shut down. However, they are included in the report because of their important role in the development of LMFBR technology from first LMFBRs to the prototype size fast reactors. The first LMFBRs (CLEMENTINE (USA), EBR-1 (USA), BR-2 (USSR), BR-5 (USSR)) and very special reactors (LAMPRE (USA), SEFOR (USA)) were not recommended by the members of the IWGFR to be included in the report

  8. Climate-relevant monitorings in Germany

    International Nuclear Information System (INIS)

    Metternich, P.

    1993-01-01

    This catalogue contains so-called meta-data; i.e. information on data. For each measuring programme or set of data, users find the address (postal address, telephone, fax-number) of the respective contact person at the beginning of the entry. The catalogue has three parts: Part A is a compilation of monitoring programmes using conventional methods adopted on the ground. Part B contains research programmes or sets of data from the field of remote sensing. In part C, data sets from time series of climate-relevant parameters are described. Section A was additionally structured according so the compartments of the climate system: Atmosphere, hydrosphere, cryosphere, biosphere. (orig./KW) [de

  9. Biotropic parameters of magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Shishlo, M.A.

    The use of magnetic fields (MF) in biology and medicine to control biological systems has led to appearance of the term, biotropic parameters of MF. They include the physical characteristics of MF, which determine the primary biologically significant physicochemical mechanisms of field action causing formation of corresponding reactions on the level of the integral organism. These parameters include MF intensity, gradient, vector, pulse frequency and shape, and duration of exposure. Factors that elicit responses by the biological system include such parameter of MF interaction with the integral organism as localization of exposure and volume of tissues interacting with the field, as well as the initial state of the organism. In essence, the findings of experimental studies of biotropic parameters of MF make it possible to control physiological processes and will aid in optimizing methods of MF therapy.

  10. Experimental technique of neutron reflection

    International Nuclear Information System (INIS)

    Chen Bo; Huang Chaoqiang; Li Xinxi

    2006-12-01

    It is presented that the classifications, structures and components of neutron reflectometer (NR), as well s functions and parameters of each components, detailed characters of NR facility 'PRN-2M'. Based on the practical experiments, the basic experimental techniques, the measurement and the related experimental settings are described, including the choice of experimental conditions, adjustments of polarized neutron beam line, basic experimental technique and approach of measurement. The above can be an instruction for NR experiments and a reference for NR construction. (authors)

  11. Irradiation creep performance of graphite relevant for pebble bed HTRs

    International Nuclear Information System (INIS)

    Kleist, G.; O'Connor, M.F.

    1980-01-01

    Irradiation - induced creep in the core reflector component graphite of high temperature reactors is of primary importance to the core designer since it provides a mechanism for the relief of internal stresses arising from differential Wigner shrinkage and thermal expansion. The experimental determination of the extent of this creep for conditions relevant to the reactor is thus imperative

  12. An old test for new neurons: refining the Morris water maze to study the functional relevance of adult hippocampal neurogenesis

    Directory of Open Access Journals (Sweden)

    Alexander eGarthe

    2013-05-01

    Full Text Available The Morris water maze represents the de-facto standard for testing hippocampal function in laboratory rodents. In the field of adult hippocampal neurogenesis, however, using this paradigm to assess the functional relevance of the new neurons yielded surprisingly inconsistent results. While some authors found aspects of water maze performance to be linked to adult neurogenesis, others obtained different results or could not demonstrate any effect of manipulating adult neurogenesis.In this review we discuss evidence that the large diversity of protocols and setups used is an important aspect in interpreting the differences in the results that have been obtained. Even simple parameters such as pool size, number and configuration of visual landmarks, or number of trials can become highly relevant for getting the new neurons involved at all. Sets of parameters are often chosen with implicit or explicit concepts in mind and these might lead to different views on the function of adult-generated neurons.We propose that the classical parameters usually used to measure spatial learning performance in the water maze might not be particularly well suited to sensitively and specifically detect the supposedly highly specific functional changes elicited by the experimental modulation of adult hippocampal neurogenesis. As adult neurogenesis is supposed to affect specific aspects of information processing only in the hippocampus, any claim for a functional relevance of the new neurons has to be based on hippocampus-specific parameters. We also placed a special emphasis on the fact that the DG facilitates the differentiation between contexts as opposed to just differentiating places.In conclusion, while the Morris water maze has proven to be one of the most effective testing paradigms to assess hippocampus-dependent spatial learning, new and more specific questions ask for new parameters. Therefore, the full potential of the water maze task remains to be tapped.

  13. Microdosing: Concept, application and relevance

    Directory of Open Access Journals (Sweden)

    Tushar Tewari

    2010-01-01

    Full Text Available The use of microdose pharmacokinetic studies as an essential tool in drug development is still to catch on. While this approach promises potential cost savings and a quantum leap in efficiencies of the drug development process, major hurdles still need to be overcome before the technique becomes commonplace and part of routine practice. Clear regulations in Europe and the USA have had an enabling effect. The lack of enabling provisions for microdosing studies in Indian regulation, despite low risk and manifest relevance for the local drug development industry, is inconsistent with the country′s aspirations to be among the leaders in pharmaceutical research.

  14. Measuring the Michel parameter ξ''

    International Nuclear Information System (INIS)

    Knowles, P.; Deutsch, J.; Egger, J.; Fetscher, W.; Foroughi, F.; Govaerts, J.; Hadri, M.; Kirch, K.; Kistryn, S.; Lang, J.; Morelle, X.; Naviliat, O.; Ninane, A.; Prieels, R.; Severijns, N.; Simons, L.; Sromicki, J.; Vandormael, S.; Hove, P. van

    1999-01-01

    Unlike the majority of Michel parameters which are consistent with the Standard Model V-A interaction, the experimental value of ξ''(=0.65±0.36) [1] is poorly known. Our experiment will measure the longitudinal polarization, P L , of positrons emitted from the decay of polarized muons. The value of P L , equal to unity in the Standard Model, will decrease for high energy positrons emitted antiparallel to the muon spin if the combination of Michel parameters ξ''/ξξ' - 1 deviates from the Standard Model value of zero

  15. Experimental modeling of injectivity loss; Modelagem experimental da perda de injetividade

    Energy Technology Data Exchange (ETDEWEB)

    Bonato, Adriano Jose do Amaral Mello; Silva, Pedro Glauto de Farias e; Gomes, Vanessa Limeira Azevedo; Santos, Adriano dos [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2012-07-01

    Produced water reinjection, suspended particles are retained in the porous media causing formation damage and injectivity decline. In general the retention of the particles occurs near the side of injection, this fact occurs in most cases, due to the size exclusion. The modeling of filtration and the consequent formation damage is essential to the project management of water injection in oil reservoirs. Thus, mathematical models are studied to better predict the distribution of particles throughout the porous media and determine the parameters of adjustment to injectivity decline. Among these models, there is the classic model which consists in determining these parameters (coefficient of filtration and formation damage). The methodology used in modeling is given from the equations the mass conservation, kinetic particle retention, the modified Darcy equation and the function formation damage. This study aimed to improve experimental modeling, including development of software for acquisition and processing of experimental data, considering the variable number of pressure measurements along the sample. The software was developed using the Labview 2011 platform and allows the determination of relevant parameters to predict injectivity loss in water injection wells. Furthermore, based on the traditional model of filtration in porous media (including depth filtration and formation of the external plaster), the software was applied to predict injectivity loss in addition to the properties of the grout. Finally, the classical models for transporting suspensions and damage to the formation were observed. (author)

  16. Evaluation of cyclone geometry and its influence on performance parameters by computational fluid dynamics (CFD

    Directory of Open Access Journals (Sweden)

    W. P. Martignoni

    2007-03-01

    Full Text Available Cyclone models have been used without relevant modifications for more than a century. Most of the attention has been focused on finding new methods to improve performance pa