Methods of experimental physics

CERN Document Server

Williams, Dudley

1962-01-01

Methods of Experimental Physics, Volume 3: Molecular Physics focuses on molecular theory, spectroscopy, resonance, molecular beams, and electric and thermodynamic properties. The manuscript first considers the origins of molecular theory, molecular physics, and molecular spectroscopy, as well as microwave spectroscopy, electronic spectra, and Raman effect. The text then ponders on diffraction methods of molecular structure determination and resonance studies. Topics include techniques of electron, neutron, and x-ray diffraction and nuclear magnetic, nuclear quadropole, and electron spin reson

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%.

Combined Teaching Method: An Experimental Study

Science.gov (United States)

Kolesnikova, Iryna V.

2016-01-01

The search for the best approach to business education has led educators and researchers to seek many different teaching strategies, ranging from the traditional teaching methods to various experimental approaches such as active learning techniques. The aim of this experimental study was to compare the effects of the traditional and combined…

Application of the photoelastic experimental hybrid method with new numerical method to the high stress distribution

International Nuclear Information System (INIS)

Hawong, Jai Sug; Lee, Dong Hun; Lee, Dong Ha; Tche, Konstantin

2004-01-01

In this research, the photoelastic experimental hybrid method with Hook-Jeeves numerical method has been developed: This method is more precise and stable than the photoelastic experimental hybrid method with Newton-Rapson numerical method with Gaussian elimination method. Using the photoelastic experimental hybrid method with Hook-Jeeves numerical method, we can separate stress components from isochromatics only and stress intensity factors and stress concentration factors can be determined. The photoelastic experimental hybrid method with Hook-Jeeves had better be used in the full field experiment than the photoelastic experimental hybrid method with Newton-Rapson with Gaussian elimination method

Results of experimental electromagnetic studies of the Crimean region

OpenAIRE

Burakhovich, T. K.; Kushnir, A. M.; Nikolaev, I. Yu.; Sheremet, E. M.; Shirkov, B. I.

2017-01-01

Spatial-temporal pattern of distribution of geomagnetic variations and the electric field on the Earth’s surface was obtained as a result of the modern experimental observations conducted in 2007—2013 along 9 profiles (48 points) by the methods of magnetotelluric sounding (MTS) and magnetovariation profiling (MVP). These profiles cross various geological structures of the Crimean region. It is possible to estimate the value of the electrical conductivity and vertical and horizontal geoelectri...

Experimental Methods for the Analysis of Optimization Algorithms

DEFF Research Database (Denmark)

, computational experiments differ from those in other sciences, and the last decade has seen considerable methodological research devoted to understanding the particular features of such experiments and assessing the related statistical methods. This book consists of methodological contributions on different...... in algorithm design, statistical design, optimization and heuristics, and most chapters provide theoretical background and are enriched with case studies. This book is written for researchers and practitioners in operations research and computer science who wish to improve the experimental assessment......In operations research and computer science it is common practice to evaluate the performance of optimization algorithms on the basis of computational results, and the experimental approach should follow accepted principles that guarantee the reliability and reproducibility of results. However...

Experimental methods in behavioral teratology

Energy Technology Data Exchange (ETDEWEB)

Zbinden, G.

1981-09-01

Efforts are made to develop toxicological techniques with which new behavioral teratogens can be recognized. The review describes the most important experimental methods which are presently explored, and which are based on a rich body of knowledge accumulated by experimental psychologists. Most of the tests were developed with small animals, mostly with rats. They range from the rather straightforward determination of various reflexes to complex behavioral situations involving mechanical devices, operant conditioning techniques and procedures evaluating social behavior. In applying these methods in routine toxicology, it is important to remember, that many behavioral effects determined in newborn and adult animals are subtle. Moreover, they are influenced by a large variety of environmental factors affecting the health and the behavior of the mothers and of the offspring in the early and later phases of development. Therefore, the experiments must be conducted under highly standardized conditions and must be controlled rigorously. It is concluded that the best experimental strategy for the evaluation of potential behavioral teratogens is not yet established. Therefore, it would be premature to decide on a fixed protocol to be included in routine animal safety experiments for drugs and other chemical substances.

Regularization of the double period method for experimental data processing

Science.gov (United States)

Belov, A. A.; Kalitkin, N. N.

2017-11-01

In physical and technical applications, an important task is to process experimental curves measured with large errors. Such problems are solved by applying regularization methods, in which success depends on the mathematician's intuition. We propose an approximation based on the double period method developed for smooth nonperiodic functions. Tikhonov's stabilizer with a squared second derivative is used for regularization. As a result, the spurious oscillations are suppressed and the shape of an experimental curve is accurately represented. This approach offers a universal strategy for solving a broad class of problems. The method is illustrated by approximating cross sections of nuclear reactions important for controlled thermonuclear fusion. Tables recommended as reference data are obtained. These results are used to calculate the reaction rates, which are approximated in a way convenient for gasdynamic codes. These approximations are superior to previously known formulas in the covered temperature range and accuracy.

An experimental method of characterization of deformable porous media

Directory of Open Access Journals (Sweden)

Sommier Alain

2012-04-01

Full Text Available A porous medium saturated with liquid and placed within a medium that undergoes a change in pressure reacts by shrinking. If the space contains the same liquid as the pores of the sample, then after a certain lapse of time the sample dilates. By measuring this dilation kinetic the specimen’s permeability can be approximated. This experimental method is called Dynamic Pressurisation. We set up an experimental apparatus to measure the permeability and the different agarose gel compressibility moduli. The liquid contained inside the gel pores is water. We have realized experiments in water and others in oil. In Scherer’s method the flow is considered only in the radial direction. To find the real permeability value we have built a numerical model considering that both the liquid and the solid are compressible. The simulations were compared to the experimental results and have allowed finding the real value of the permeability by considering the flow in both radial and axial directions.

The Bigfoot Drive; Experimental Results

Science.gov (United States)

Baker, Kevin; Thomas, Cliff; Khan, Shahab; Casey, Daniel; Spears, Brian; Nora, Ryan; Munro, Davis; Eder, David; Milovich, Jose; Berger, Dick; Strozzi, David; Goyon, Clement; Turnbull, David; Ma, Tammy; Izumi, Nobuhiko; Benedetti, Robin; Millot, Marius; Celliers, Peter; Yeamans, Charles; Hatarik, Robert; Landen, Nino; Hurricane, Omar; Callahan, Debbie

2016-10-01

The Bigfoot platform was developed on the National Ignition Facility to investigate low convergence, high adiabat, high rhoR hotspot implosions. This platform was designed to be less susceptible to wall motion, LPI and CBET and to be more robust against capsule hydrodynamic instabilities. To date experimental studies have been carried out at two hohlraum scales, a 5.75 and 5.4 mm diameter hohlraum. We will present experimental results from these tuning campaigns including the shape vs. cone fraction, surrogacy comparisons of self-emission from the capsules vs. radiography of the imploding capsule and doped vs. undoped capsules. Prepared by LLNL under Contract DE-AC52-07NA27344.

Experimental results supporting the concept of one-sided muon tomography

Energy Technology Data Exchange (ETDEWEB)

Boniface, K., E-mail: bonifak@mcmaster.ca [McMaster University, Hamilton, ON (Canada); Jonkmans, G. [Canadian Nuclear Laboratories, Chalk River, ON (Canada); Buijs, A. [McMaster University, Hamilton, ON (Canada); Erlandson, A.; Livingstone, S. [Canadian Nuclear Laboratories, Chalk River, ON (Canada)

2015-07-01

Naturally occurring cosmic-ray muons have been shown to exhibit properties ideal for imaging the interior of structures containing material of high density and atomic number. The commonly used method for 3D imaging requires two modules of detection in order to measure muon scattering. This paper provides experimental results for a novel 3D imaging method that uses a reconstruction algorithm common to medical imaging and only one module of detection in order to measure the attenuation of the muon flux at several angles of rotation around a structure. (author)

Experimental validation for calcul methods of structures having shock non-linearity

International Nuclear Information System (INIS)

Brochard, D.; Buland, P.

1987-01-01

For the seismic analysis of non-linear structures, numerical methods have been developed which need to be validated on experimental results. The aim of this paper is to present the design method of a test program which results will be used for this purpose. Some applications to nuclear components will illustrate this presentation [fr

Heavy ions testing experimental results on programmable integrated circuits

International Nuclear Information System (INIS)

Velazco, R.; Provost-Grellier, A.

1988-01-01

The natural radiation environment in space has been shown to produce anomalies in satellite-borne microelectronics. It becomes then mandatory to define qualification strategies allowing to choose the less vulnerable circuits. In this paper, is presented a strategy devoted to one of the most critical effects, the soft errors (so called upset). The method addresses programmable integrated circuits i.e. circuits able to execute an instruction or command set. Experimental results on representative circuits will illustrate the approach. 11 refs [fr

Calculating buoy response for a wave energy converter—A comparison of two computational methods and experimental results

Directory of Open Access Journals (Sweden)

Linnea Sjökvist

2017-05-01

Full Text Available When designing a wave power plant, reliable and fast simulation tools are required. Computational fluid dynamics (CFD software provides high accuracy but with a very high computational cost, and in operational, moderate sea states, linear potential flow theories may be sufficient to model the hydrodynamics. In this paper, a model is built in COMSOL Multiphysics to solve for the hydrodynamic parameters of a point-absorbing wave energy device. The results are compared with a linear model where the hydrodynamical parameters are computed using WAMIT, and to experimental results from the Lysekil research site. The agreement with experimental data is good for both numerical models.

Alignment procedure for the VIRGO interferometer: experimental results from the Frascati Prototype

International Nuclear Information System (INIS)

Babusci, D.; Giordano, G.; Matone, G.; Matone, L.; Sannibale, V.

1996-07-01

A small fixed-mirrors Michelson interferometer has been suggested for VIRGO. The experimental results are excellent and fully confirm the adequacy of the method. The minimum angular misalignment that can be detected in the present set-up is 10 nrad

Experimental Results of Guided Wave Travel Time Tomography

Science.gov (United States)

Volker, Arno; Mast, Arjan; Bloom, Joost

2010-02-01

Corrosion is one of the industries major issues regarding the integrity of assets. Currently inspections are conducted at regular intervals to ensure a sufficient integrity level of these assets. Both economical and social requirements are pushing the industry to even higher levels of availability, reliability and safety of installations. The concept of predictive maintenance using permanent sensors that monitor the integrity of an installation is an interesting addition to the current method of periodic inspections reducing uncertainty and extending inspection intervals. Guided wave travel time tomography is a promising method to monitor the wall thickness quantitatively over large areas. Obviously the robustness and reliability of such a monitoring system is of paramount importance. Laboratory experiments have been carried out on a 10″ pipe with a nominal wall thickness of 8 mm. Multiple, inline defects have been created with a realistic morphology. The depth of the defects was increased stepwise from 0.5 mm to 2 mm. Additionally the influences of the presence of liquid inside the pipe and surface roughness have been evaluated as well. Experimental results show that this method is capable of providing quantitative wall thickness information over a distance of 4 meter, with a sufficient accuracy such that results can be used for trending. The method has no problems imaging multiple defects.

Experimental methods for the analysis of optimization algorithms

CERN Document Server

Bartz-Beielstein, Thomas; Paquete, Luis; Preuss, Mike

2010-01-01

In operations research and computer science it is common practice to evaluate the performance of optimization algorithms on the basis of computational results, and the experimental approach should follow accepted principles that guarantee the reliability and reproducibility of results. However, computational experiments differ from those in other sciences, and the last decade has seen considerable methodological research devoted to understanding the particular features of such experiments and assessing the related statistical methods. This book consists of methodological contributions on diffe

Treating experimental data of inverse kinetic method by unitary linear regression analysis

International Nuclear Information System (INIS)

Zhao Yusen; Chen Xiaoliang

2009-01-01

The theory of treating experimental data of inverse kinetic method by unitary linear regression analysis was described. Not only the reactivity, but also the effective neutron source intensity could be calculated by this method. Computer code was compiled base on the inverse kinetic method and unitary linear regression analysis. The data of zero power facility BFS-1 in Russia were processed and the results were compared. The results show that the reactivity and the effective neutron source intensity can be obtained correctly by treating experimental data of inverse kinetic method using unitary linear regression analysis and the precision of reactivity measurement is improved. The central element efficiency can be calculated by using the reactivity. The result also shows that the effect to reactivity measurement caused by external neutron source should be considered when the reactor power is low and the intensity of external neutron source is strong. (authors)

Experimental and mathematical modeling methods for the investigation of toxicological interactions

International Nuclear Information System (INIS)

El-Masri, Hisham A.

2007-01-01

While procedures have been developed and used for many years to assess risk and determine acceptable exposure levels to individual chemicals, most cases of environmental contamination can result in concurrent or sequential exposure to more than one chemical. Toxicological predictions of such combinations must be based on an understanding of the mechanisms of action and interaction of the components of the mixtures. Statistical and experimental methods test the existence of toxicological interactions in a mixture. However, these methods are limited to experimental data ranges for which they are derived, in addition to limitations caused by response differences from experimental animals to humans. Empirical methods such as isobolograms, median-effect principle and response surface methodology (RSM) are based on statistical experimental design and regression of data. For that reason, the predicted response surfaces can be used for extrapolation across dose regions where interaction mechanisms are not anticipated to change. In general, using these methods for predictions can be problematic without including biologically based mechanistic descriptions that can account for dose and species differences. Mechanistically based models, such as physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models, include explicit descriptions of interaction mechanisms which are related to target tissues levels. These models include dose-dependent mechanistic hypotheses of toxicological interactions which can be tested by model-directed experimental design and used to identify dose regions where interactions are not significant

F(α) curves: Experimental results

International Nuclear Information System (INIS)

Glazier, J.A.; Gunaratne, G.; Libchaber, A.

1988-01-01

We study the transition to chaos at the golden and silver means for forced Rayleigh-Benard (RB) convection in mercury. We present f(α) curves below, at, and above the transition, and provide comparisons to the curves calculated for the one-dimensional circle map. We find good agreement at both the golden and silver means. This confirms our earlier observation that for low amplitude forcing, forced RB convection is well described by the one-dimensional circle map and indicates that the f(α) curve is a good measure of the approach to criticality. For selected subcritical experimental data sets we calculate the degree of subcriticality. We also present both experimental and calculated results for f(α) in the presence of a third frequency. Again we obtain agreement: The presence of random noise or a third frequency narrows the right-hand (negative q) side of the f(α) curve. Subcriticality results in symmetrically narrowed curves. We can also distinguish these cases by examining the power spectra and Poincare sections of the time series

Experimental results obtained at GANIL

International Nuclear Information System (INIS)

Borrel, V.

1993-01-01

A review of experimental results obtained at GANIL on the study of nuclear structure and nuclear reactions with secondary radioactive beams is presented. Mass measurements by means of the GANIL cyclotrons are described. The possibilities of GANIL/LISE3 for the production and separation of radioactive beams are illustrated through a large variety of experiments. (author). 19 refs., 8 figs

New experimental results on strangeness production

International Nuclear Information System (INIS)

Sapozhnikov, M.G.

1998-01-01

New experimental results on the production of φ and f 2 ' (1525) mesons in the annihilation of stopped antiprotons are discussed. The explanation of these facts in the framework of the polarized strangeness model is considered

AN EXPERIMENTAL ASSESSMENT OF THE PLATE HEAT EXCHANGER CHARACTERISTICS BY WILSON PLOT METHOD

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Jan Opatřil

2016-10-01

Full Text Available An aim of this paper is suggestion of the evaluation method based on the experimental data and the Wilson plot method for the Plate Heat Exchangers (PHE. For the purpose of the project the new experimental loop was built for the testing of PHE to obtain the overhaul heat transfer coefficient and pressure drop between inlet and outlet of the fluid. The measurement were done for three different PHE with the performance range 30-100kW. The working fluid was water on both sides of the PHE. The differences are in number of pates as well as in extrusion profiles. The Wilson plot evaluation method was involved for the processing experimental data. To obtain more accurate correlations between the experimental data and theoretical results yield of the Wilson plot, the method was enhanced by the measured pressure drop involving. This approach could be useful for PHE designing software and for the manufacturing company.

A method for experimental modal separation

Science.gov (United States)

Hallauer, W. L., Jr.

1977-01-01

A method is described for the numerical simulation of multiple-shaker modal survey testing using simulated experimental data to optimize the shaker force-amplitude distribution for the purpose of isolating individual modes of vibration. Inertia, damping, stiffness, and model data are stored on magnetic disks, available by direct access to the interactive FORTRAN programs which perform all computations required by this relative force amplitude distribution method.

Design and experimental results of the 1-T Bitter Electromagnet Testing Apparatus (BETA)

Science.gov (United States)

Bates, E. M.; Birmingham, W. J.; Romero-Talamás, C. A.

2018-05-01

The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) technical prototype of the 10 T Adjustable Long Pulsed High-Field Apparatus. BETA's final design specifications are highlighted in this paper which include electromagnetic, thermal, and stress analyses. We discuss here the design and fabrication of BETA's core, vessel, cooling, and electrical subsystems. The electrical system of BETA is composed of a scalable solid-state DC breaker circuit. Experimental results display the stable operation of BETA at 1 T. These results are compared to both analytical design and finite element calculations. Experimental results validate analytical magnet designing methods developed at the Dusty Plasma Laboratory. The theoretical steady state maxima and the limits of BETA's design are explored in this paper.

Review of experimental methods for evaluating effective delayed neutron fraction

Energy Technology Data Exchange (ETDEWEB)

Yamane, Yoshihiro [Nagoya Univ. (Japan). School of Engineering

1997-03-01

The International Effective Delayed Neutron Fraction ({beta}{sub eff}) Benchmark Experiments have been carried out at the Fast Critical Assembly of Japan Atomic Energy Research Institute since 1995. Researchers from six countries, namely France, Italy, Russia, U.S.A., Korea, and Japan, participate in this FCA project. Each team makes use of each experimental method, such as Frequency Method, Rossi-{alpha} Method, Nelson Number Method, Cf Neutron Source Method, and Covariance Method. In this report these experimental methods are reviewed. (author)

Experimental Methods for the Analysis of Optimization Algorithms

DEFF Research Database (Denmark)

of solution quality, runtime and other measures; and the third part collects advanced methods from experimental design for configuring and tuning algorithms on a specific class of instances with the goal of using the least amount of experimentation. The contributor list includes leading scientists......, computational experiments differ from those in other sciences, and the last decade has seen considerable methodological research devoted to understanding the particular features of such experiments and assessing the related statistical methods. This book consists of methodological contributions on different...

Acquisition of Psychomotor Skills in Dentistry: An Experimental Teaching Method.

Science.gov (United States)

Vann, William F., Jr.; And Others

1981-01-01

A traditional method of teaching psychomotor skills in a preclinical restorative dentistry laboratory course was compared with an experimental method. The experimental group was taught using a guided systematic approach that relied on detailed checklists and exhaustive faculty feedback. (Author/MLW)

Methods for experimental design principles and applications for physicists and chemists

CERN Document Server

Goupy, J

1993-01-01

A method for organizing and conducting scientific experiments is described in this volume which enables experimenters to reduce the number of trials run, while retaining all the parameters that may influence the result. The choice of ideal experiments is based on mathematical concepts, but the author adopts a practical approach and uses theory only when necessary. Written for experimenters by an experimenter, it is an introduction to the philosophy of scientific investigation. Researchers with limited time and resources at their disposal will find this text a valuable guide for solving specific problems efficiently. The presentation makes extensive use of examples, and the approach and methods are graphical rather than numerical. All calculations can be performed on a personal computer; readers are assumed to have no previous knowledge of the subject. The presentation is such that the beginner may acquire a thorough understanding of the basic concepts. However, there is also sufficient material to challenge t...

An analytical model for backscattered luminance in fog: comparisons with Monte Carlo computations and experimental results

International Nuclear Information System (INIS)

Taillade, Frédéric; Dumont, Eric; Belin, Etienne

2008-01-01

We propose an analytical model for backscattered luminance in fog and derive an expression for the visibility signal-to-noise ratio as a function of meteorological visibility distance. The model uses single scattering processes. It is based on the Mie theory and the geometry of the optical device (emitter and receiver). In particular, we present an overlap function and take the phase function of fog into account. The results of the backscattered luminance obtained with our analytical model are compared to simulations made using the Monte Carlo method based on multiple scattering processes. An excellent agreement is found in that the discrepancy between the results is smaller than the Monte Carlo standard uncertainties. If we take no account of the geometry of the optical device, the results of the model-estimated backscattered luminance differ from the simulations by a factor 20. We also conclude that the signal-to-noise ratio computed with the Monte Carlo method and our analytical model is in good agreement with experimental results since the mean difference between the calculations and experimental measurements is smaller than the experimental uncertainty

Validation of Experimental whole-body SAR Assessment Method in a Complex Indoor Environment

DEFF Research Database (Denmark)

Bamba, Aliou; Joseph, Wout; Vermeeren, Gunter

2012-01-01

Assessing experimentally the whole-body specific absorption rate (SARwb) in a complex indoor environment is very challenging. An experimental method based on room electromagnetics theory (accounting only the Line-Of-Sight as specular path) to assess the whole-body SAR is validated by numerical...... of the proposed method is that it allows discarding the computation burden because it does not use any discretizations. Results show good agreement between measurement and computation at 2.8 GHz, as long as the plane wave assumption is valid, i.e., for high distances from the transmitter. Relative deviations 0...

Numerical analysis of temperature field during hardfacing process and comparison with experimental results

Directory of Open Access Journals (Sweden)

Lazić Vukić N.

2014-01-01

Full Text Available The three-dimensional transient nonlinear thermal analysis of the hard facing process is performed by using the finite element method. The simulations were executed on the open source Salome platform using the open source finite element solver Code_Aster. The Gaussian double ellipsoid was selected in order to enable greater possibilities for the calculation of the moving heat source. The numerical results were compared with available experimental results.

Experimental verification of neutron emission method for measuring of fissile material content in spent fuel

International Nuclear Information System (INIS)

Abou-Zaid, A.A.; Pytel, K.

1999-01-01

A non-destructive method of measurement of fissile nuclides content remained in spent fuel from research reactor is presented. The method, called the neutron emission one, is based on counting of fission neutrons emitted from fissile isotopes: 235 U, 239 Pu, 241 Pu. Fissions are induced mainly by neutrons supplied by the external neutron source. Another effects contribute also to the measured neutron population, e. g. source neutrons from penetrating the fuel without being captured and scattered, neutrons (α,n) reactions and from spontaneous fissions of actinides. Complexity of phenomena occurring within the measurement facility required the detailed numerical simulation and experimental studies prior design of ultimate measurement stand. In the previous paper, the results of Monte Carlo simulation on optimisation of measuring stand for neutron emission method were presented. On the basis of those results, the experimental stand for Maria reactor fuel investigation has been designed and manufactured. The present paper, being the continuation of previous one, contains the description of experimental facility and the results of measurements for the fresh fuel (without burnup) and the fuel mock-up (without fissile materials). Although some discrepancies were found between Monte Carlo and experimental results, the main conclusions concerning the optimal geometry of measuring facility have been confirmed. (author)

Experimental method for investigating helium effects in irradiated vanadium

International Nuclear Information System (INIS)

Smith, D.L.; Matsui, H.; Greenwood, L.; Loomis, B.

1987-10-01

Analyses have been performed which indicate that an effective method for experimentally investigating helium effects in neutron irradiated vanadium base alloys can be developed. The experimental procedure involves only modest modifications to existing procedures currently used for irradiation testing of vanadium-base alloys in the FFTF reactor. Helium is generated in the vanadium alloy by decay of tritium which is either preinjected or generated within the test capsule. Calculations indicate that nearly constant He/dpa ratios of desired magnitude can be attained by proper selection of experimental parameters. The proposed method could have a major impact on the development of vanadium base alloys for fusion reactor applications. 8 refs., 4 figs

Shape sensing methods: Review and experimental comparison on a wing-shaped plate

Science.gov (United States)

Gherlone, Marco; Cerracchio, Priscilla; Mattone, Massimiliano

2018-05-01

Shape sensing, i.e., the reconstruction of the displacement field of a structure from some discrete surface strain measurements, is a fundamental capability for the structural health management of critical components. In this paper, a review of the shape sensing methodologies available in the open literature and of the different applications is provided. Then, for the first time, an experimental comparative study is presented among the main approaches in order to highlight their relative merits in presence of uncertainties affecting real applications. These approaches are, namely, the inverse Finite Element Method, the Modal Method and Ko's Displacement Theory. A brief description of these methods is followed by the presentation of the experimental test results. A cantilevered, wing-shaped aluminum plate is let deform under its own weight, leading to bending and twisting. Using the experimental strain measurements as input data, the deflection field of the plate is reconstructed using the three aforementioned approaches and compared with the actual measured deflection. The inverse Finite Element Method is proven to be slightly more accurate and particularly attractive because it is versatile with respect to the boundary conditions and it does not require any information about material properties and loading conditions.

Predictions of High Energy Experimental Results

Directory of Open Access Journals (Sweden)

Comay E.

2010-10-01

Full Text Available Eight predictions of high energy experimental results are presented. The predictions contain the $Sigma ^+$ charge radius and results of two kinds of experiments using energetic pionic beams. In addition, predictions of the failure to find the following objects are presented: glueballs, pentaquarks, Strange Quark Matter, magnetic monopoles searched by their direct interaction with charges and the Higgs boson. The first seven predictions rely on the Regular Charge-Monopole Theory and the last one relies on mathematical inconsistencies of the Higgs Lagrangian density.

Thermodynamic properties of 9-fluorenone: Mutual validation of experimental and computational results

International Nuclear Information System (INIS)

Chirico, Robert D.; Kazakov, Andrei F.; Steele, William V.

2012-01-01

Highlights: ► Heat capacities were measured for the temperature range 5 K to 520 K. ► Vapor pressures were measured for the temperature range 368 K to 668 K. ► The enthalpy of combustion was measured and the enthalpy of formation was derived. ► Calculated and derived properties for the ideal gas are in excellent accord. ► Thermodynamic consistency analysis revealed anomalous literature data. - Abstract: Measurements leading to the calculation of thermodynamic properties for 9-fluorenone (IUPAC name 9H-fluoren-9-one and Chemical Abstracts registry number [486-25-9]) in the ideal-gas state are reported. Experimental methods were adiabatic heat-capacity calorimetry, inclined-piston manometry, comparative ebulliometry, and combustion calorimetry. Critical properties were estimated. Molar entropies for the ideal-gas state were derived from the experimental studies at selected temperatures T between T = 298.15 K and T = 600 K, and independent statistical calculations were performed based on molecular geometry optimization and vibrational frequencies calculated at the B3LYP/6 − 31 + G(d,p) level of theory. Values derived with the independent methods are shown to be in excellent accord with a scaling factor of 0.975 applied to the calculated frequencies. This same scaling factor was successfully applied in the analysis of results for other polycyclic molecules, as described in recent articles by this research group. All experimental results are compared with property values reported in the literature. Thermodynamic consistency between properties is used to show that several studies in the literature are erroneous.

Reflectivity of 1D photonic crystals: A comparison of computational schemes with experimental results

Science.gov (United States)

Pérez-Huerta, J. S.; Ariza-Flores, D.; Castro-García, R.; Mochán, W. L.; Ortiz, G. P.; Agarwal, V.

2018-04-01

We report the reflectivity of one-dimensional finite and semi-infinite photonic crystals, computed through the coupling to Bloch modes (BM) and through a transfer matrix method (TMM), and their comparison to the experimental spectral line shapes of porous silicon (PS) multilayer structures. Both methods reproduce a forbidden photonic bandgap (PBG), but slowly-converging oscillations are observed in the TMM as the number of layers increases to infinity, while a smooth converged behavior is presented with BM. The experimental reflectivity spectra is in good agreement with the TMM results for multilayer structures with a small number of periods. However, for structures with large amount of periods, the measured spectral line shapes exhibit better agreement with the smooth behavior predicted by BM.

Development of advanced methods for analysis of experimental data in diffusion

Science.gov (United States)

Jaques, Alonso V.

. Case studies are presented to demonstrate the reliability and the stability of the method. To the best of our knowledge there is no published analysis of the effects of experimental errors on the reliability of the estimates for the diffusivities. For the case of linear multicomponent diffusion, we analyze the effects of the instrument analytical spot size, positioning uncertainty, and concentration uncertainty on the resulting values of the diffusivities. These effects are studied using Monte Carlo method on simulated experimental data. Several useful scaling relationships were identified which allow more rigorous and quantitative estimates of the errors in the measured data, and are valuable for experimental design. To further analyze anomalous diffusion processes, where traditional diffusional transport equations do not hold, we explore the use of fractional calculus in analytically representing these processes is proposed. We use the fractional calculus approach for anomalous diffusion processes occurring through a finite plane sheet with one face held at a fixed concentration, the other held at zero, and the initial concentration within the sheet equal to zero. This problem is related to cases in nature where diffusion is enhanced relative to the classical process, and the order of differentiation is not necessarily a second--order differential equation. That is, differentiation is of fractional order alpha, where 1 ≤ alpha < 2. For alpha = 2, the presented solutions reduce to the classical second-order diffusion solution for the conditions studied. The solution obtained allows the analysis of permeation experiments. Frequently, hydrogen diffusion is analyzed using electrochemical permeation methods using the traditional, Fickian-based theory. Experimental evidence shows the latter analytical approach is not always appropiate, because reported data shows qualitative (and quantitative) deviation from its theoretical scaling predictions. Preliminary analysis of

Experimental Methods in Psychology and Cognitive and Affective Neuroscience

OpenAIRE

Habekost, Thomas; Nielsen, Julie Hassing

2014-01-01

Laboratory experiments have always been important in psychology and are as commonly used today as ever due to the dominating position of cognitive research in international psychology. This trend has been further strengthened by recent developments in cognitive neuroscience, where experimental studies are central. Recently, experimental studies within the fi eld of affective neuroscience have also received attention. Notwithstanding, experimental methods remain controversial also in psychology...

A new method to determine the number of experimental data using statistical modeling methods

Energy Technology Data Exchange (ETDEWEB)

Jung, Jung-Ho; Kang, Young-Jin; Lim, O-Kaung; Noh, Yoojeong [Pusan National University, Busan (Korea, Republic of)

2017-06-15

For analyzing the statistical performance of physical systems, statistical characteristics of physical parameters such as material properties need to be estimated by collecting experimental data. For accurate statistical modeling, many such experiments may be required, but data are usually quite limited owing to the cost and time constraints of experiments. In this study, a new method for determining a rea- sonable number of experimental data is proposed using an area metric, after obtaining statistical models using the information on the underlying distribution, the Sequential statistical modeling (SSM) approach, and the Kernel density estimation (KDE) approach. The area metric is used as a convergence criterion to determine the necessary and sufficient number of experimental data to be acquired. The pro- posed method is validated in simulations, using different statistical modeling methods, different true models, and different convergence criteria. An example data set with 29 data describing the fatigue strength coefficient of SAE 950X is used for demonstrating the performance of the obtained statistical models that use a pre-determined number of experimental data in predicting the probability of failure for a target fatigue life.

Comparison the Results of Numerical Simulation And Experimental Results for Amirkabir Plasma Focus Facility

Science.gov (United States)

Goudarzi, Shervin; Amrollahi, R.; Niknam Sharak, M.

2014-06-01

In this paper the results of the numerical simulation for Amirkabir Mather-type Plasma Focus Facility (16 kV, 36μF and 115 nH) in several experiments with Argon as working gas at different working conditions (different discharge voltages and gas pressures) have been presented and compared with the experimental results. Two different models have been used for simulation: five-phase model of Lee and lumped parameter model of Gonzalez. It is seen that the results (optimum pressures and current signals) of the Lee model at different working conditions show better agreement than lumped parameter model with experimental values.

Comparison the results of numerical simulation and experimental results for Amirkabir plasma focus facility

International Nuclear Information System (INIS)

Goudarzi, Shervin; Amrollahi, R; Sharak, M Niknam

2014-01-01

In this paper the results of the numerical simulation for Amirkabir Mather-type Plasma Focus Facility (16 kV, 36μF and 115 nH) in several experiments with Argon as working gas at different working conditions (different discharge voltages and gas pressures) have been presented and compared with the experimental results. Two different models have been used for simulation: five-phase model of Lee and lumped parameter model of Gonzalez. It is seen that the results (optimum pressures and current signals) of the Lee model at different working conditions show better agreement than lumped parameter model with experimental values.

Experimental Method for Characterizing Electrical Steel Sheets in the Normal Direction

Directory of Open Access Journals (Sweden)

Thierry Belgrand

2010-10-01

Full Text Available This paper proposes an experimental method to characterise magnetic laminations in the direction normal to the sheet plane. The principle, which is based on a static excitation to avoid planar eddy currents, is explained and specific test benches are proposed. Measurements of the flux density are made with a sensor moving in and out of an air-gap. A simple analytical model is derived in order to determine the permeability in the normal direction. The experimental results for grain oriented steel sheets are presented and a comparison is provided with values obtained from literature.

PDX experimental results in FY82

International Nuclear Information System (INIS)

Kaye, S.M.; Bell, M.; Bol, K.

1983-08-01

This report presents a detailed summary of the major experimental results of PDX in FY82 and represents the efforts of the entire PDX group. Topics covered include β-scaling and fishbone studies, fluctuations, disruptions, impurities and impurity transport, power handling, limiter conditioning, edge studies, plasma fueling, counter-injection, and diagnostic development. A less detailed version will appear as the FY82 PDX contribution to the PPPL Annual Report

Experimental results of active control on a large structure to suppress vibration

Science.gov (United States)

Dunn, H. J.

1991-01-01

Three design methods, Linear Quadratic Gaussian with Loop Transfer Recovery (LQG/LTR), H-infinity, and mu-synthesis, are used to obtain compensators for suppressing the vibrations of a 10-bay vertical truss structure, a component typical of what may be used to build a large space structure. For the design process the plant dynamic characteristics of the structure were determined experimentally using an identification method. The resulting compensators were implemented on a digital computer and tested for their ability to suppress the first bending mode response of the 10-bay vertical truss. Time histories of the measured motion are presented, and modal damping obtained during the experiments are compared with analytical predictions. The advantages and disadvantages of using the various design methods are discussed.

Experimental Method for Plotting S-N Curve with a Small Number of Specimens

Directory of Open Access Journals (Sweden)

Strzelecki Przemysław

2016-12-01

Full Text Available The study presents two approaches to plotting an S-N curve based on the experimental results. The first approach is commonly used by researchers and presented in detail in many studies and standard documents. The model uses a linear regression whose parameters are estimated by using the least squares method. A staircase method is used for an unlimited fatigue life criterion. The second model combines the S-N curve defined as a straight line and the record of random occurrence of the fatigue limit. A maximum likelihood method is used to estimate the S-N curve parameters. Fatigue data for C45+C steel obtained in the torsional bending test were used to compare the estimated S-N curves. For pseudo-random numbers generated by using the Mersenne Twister algorithm, the estimated S-N curve for 10 experimental results plotted by using the second model, estimates the fatigue life in the scatter band of the factor 3. The result gives good approximation, especially regarding the time required to plot the S-N curve.

Reverse Schreinemakers Method for Experimental Analysis of Mixed-Solvent Electrolyte Systems

DEFF Research Database (Denmark)

Fosbøl, Philip Loldrup; Thomsen, Kaj; Stenby, Erling Halfdan

2009-01-01

the reverse Schreinemakers (RS) method. The method is based on simple mass balance principles similar to the wet residues method. It allows for accurate determination of the mixed-solvent phase composition even though part of the solvent may precipitate as complexes between solvent and salt. Discrepancies......A method based on Schreinemakers's tie-line theory of 1893 is derived for determining the composition and phase amounts in solubility experiments for multi-solvent electrolyte systems. The method uses the lever rule in reverse compared to Schreinemakers's wet residue method, and is therefore called...... from determining the composition of salt mixtures by pH titration are discussed, and the derived method significantly improves the obtained result from titration. Furthermore, the method reduces the required experimental work needed for analysis of phase composition. The method is applicable to multi...

Integrated visualization of simulation results and experimental devices in virtual-reality space

International Nuclear Information System (INIS)

Ohtani, Hiroaki; Ishiguro, Seiji; Shohji, Mamoru; Kageyama, Akira; Tamura, Yuichi

2011-01-01

We succeeded in integrating the visualization of both simulation results and experimental device data in virtual-reality (VR) space using CAVE system. Simulation results are shown using Virtual LHD software, which can show magnetic field line, particle trajectory, and isosurface of plasma pressure of the Large Helical Device (LHD) based on data from the magnetohydrodynamics equilibrium simulation. A three-dimensional mouse, or wand, determines the initial position and pitch angle of a drift particle or the starting point of a magnetic field line, interactively in the VR space. The trajectory of a particle and the stream-line of magnetic field are calculated using the Runge-Kutta-Huta integration method on the basis of the results obtained after pointing the initial condition. The LHD vessel is objectively visualized based on CAD-data. By using these results and data, the simulated LHD plasma can be interactively drawn in the objective description of the LHD experimental vessel. Through this integrated visualization, it is possible to grasp the three-dimensional relationship of the positions between the device and plasma in the VR space, opening a new path in contribution to future research. (author)

Evaluation of thermal ratchetting on axisymmetric thin shells at the free level of sodium: Experimental results and elastic analysis

International Nuclear Information System (INIS)

Cabrillat, M.T.; Gatt, J.M.; Schoulguine, P.; Skiara, A.

1993-01-01

Startup operations and load variations for a FBR reactor (Fast Breeder Reactor) cause sodium level variations in the vessels which exert stresses on the emergent shells in the free level area. The loading of these shells is mainly linked to the axial thermal gradient, primary stresses being generally low or negligible as are the radial thermal gradients. Under the effect of these variable axial thermal gradients, there is a risk of progressive deformation even in the absence of primary type stresses. The simplified methods of analysis (Bree diagram, efficiency diagram) proposed in the design codes (Code Case and RCCMR) are not applicable in this specific case where primary type stresses are negligible. In recent years, many studies and experimental programmes have been undertaken in order to propose more reliable methods of analysis for these structures. This paper describes the experimental program, called VINIL, developed at the CEA at Cadarache. After a brief description of the experimental facility and of the experimental results, this paper proposes an evaluation of the risk of progressive deformation on an elastic basis: various simplified methods of analysis were used and are compared with experimental results

Master-Slave synchronization of robot manipulators: experimental results

NARCIS (Netherlands)

Bondhus, A.K.; Pettersen, K.Y.; Nijmeijer, H.

2005-01-01

This paper presents experimental results for master-slave synchronization of two robot manipulators using a recently developed observer-controller scheme. The paper aims to investigate the value and the limitations of the theory. In particular, the theoretical result of uniform ultimate boundedness

A Normalized Transfer Matrix Method for the Free Vibration of Stepped Beams: Comparison with Experimental and FE(3D Methods

Directory of Open Access Journals (Sweden)

Tamer Ahmed El-Sayed

2017-01-01

Full Text Available The exact solution for multistepped Timoshenko beam is derived using a set of fundamental solutions. This set of solutions is derived to normalize the solution at the origin of the coordinates. The start, end, and intermediate boundary conditions involve concentrated masses and linear and rotational elastic supports. The beam start, end, and intermediate equations are assembled using the present normalized transfer matrix (NTM. The advantage of this method is that it is quicker than the standard method because the size of the complete system coefficient matrix is 4 × 4. In addition, during the assembly of this matrix, there are no inverse matrix steps required. The validity of this method is tested by comparing the results of the current method with the literature. Then the validity of the exact stepped analysis is checked using experimental and FE(3D methods. The experimental results for stepped beams with single step and two steps, for sixteen different test samples, are in excellent agreement with those of the three-dimensional finite element FE(3D. The comparison between the NTM method and the finite element method results shows that the modal percentage deviation is increased when a beam step location coincides with a peak point in the mode shape. Meanwhile, the deviation decreases when a beam step location coincides with a straight portion in the mode shape.

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

Experimental results for an experimental condensation heat exchanger with a spiral minichanel tube. Comparison to numerical imulations

Directory of Open Access Journals (Sweden)

Hrubý J.

2013-04-01

Full Text Available The paper describes new results for an experimental heat exchanger equipped with a single corrugated capillary tube, basic information about the measurements and the experimental setup. Some of the results were compared with numerical simulations.

Experimental Methods in Psychology and Cognitive and Affective Neuroscience

DEFF Research Database (Denmark)

Habekost, Thomas; Nielsen, Julie Hassing

2014-01-01

studies are central. Recently, experimental studies within the field of affective neuroscience have also received attention. Notwithstanding, experimental methods remain controversial also in psychology, and one should carefully weigh their advantages against their drawbacks.......Laboratory experiments have always been important in psychology and are as commonly used today as ever due to the dominating position of cognitive research in international psychology. This trend has been further strengthened by recent developments in cognitive neuroscience, where experimental...

Numerical and experimental results of a passive free yawing downwind wind turbine

Energy Technology Data Exchange (ETDEWEB)

Verelst, D.R.S.

2013-09-15

The background of this PhD study concerns a medium sized 3 bladed wind turbine in a free yawing and downwind configuration. Largely funded by an EU Marie-Curie IAPP grant, the project was jointly setup by the renewable energy consultant 3E, DTU Wind Energy and the TU Delft. The 3 bladed free yawing downwind concept is pursued in an attempt to increase the robustness of a wind turbine by eliminating the traditionally actively controlled, and sometimes failure prone yawing mechanism. Under certain conditions, such as for remote (off shore) and off grid applications, a decreased failure rate can increase the economical competitiveness significantly compared to more traditional power supplies. This work presents aeroelastic analysis and results of a wind tunnel test campaign for the 3 bladed free yawing downwind concept. The investigated topics concern free yawing stability and how it is affected by coning angle, blade sweep, and blade flexibility using both numerical and experimental methods. The wind tunnel tests were organized in the Open Jet Facility of the TU Delft, and the thesis discusses the experiment's design, construction, operation, and gives an analysis of the results. It provides a dataset to compare aeroelastic simulations with experimental results for varying yawed inflow conditions and free yawing stability. The experimental data scope is limited to rotor speed, tower base bending moment, yaw angle, and blade root flapwise bending moments measurements. Other work covered during the PhD study is a parametric blade sweep investigation for the NREL 5MW turbine, and a detailed study on load extrapolation methods based on aeroelastic simulations. It is concluded that the 3 bladed, free yawing, and downwind wind turbine can operate in a stable manner. However, numerical studies indicate a less stable operating region when the rotor flow is about to stall. The experiments confirmed the free yawing stability, but the unstable region indicated in the

Experimental Results for Direction of Arrival Estimation with a Single Acoustic Vector Sensor in Shallow Water

Directory of Open Access Journals (Sweden)

Alper Bereketli

2015-01-01

Full Text Available We study the performances of several computationally efficient and simple techniques for estimating direction of arrival (DOA of an underwater acoustic source using a single acoustic vector sensor (AVS in shallow water. Underwater AVS is a compact device, which consists of one hydrophone and three accelerometers in a packaged form, measuring scalar pressure and three-dimensional acceleration simultaneously at a single position. A very controlled experimental setup is prepared to test how well-known techniques, namely, arctan-based, intensity-based, time domain beamforming, and frequency domain beamforming methods, perform in estimating DOA of a source in different circumstances. Experimental results reveal that for almost all cases beamforming techniques perform best. Moreover, arctan-based method, which is the simplest of all, provides satisfactory results for practical purposes.

Calculation of Impedance from Multibunch Synchronous Phases: Theory and Experimental Results

International Nuclear Information System (INIS)

Prabhakar, Shyam

1998-01-01

A novel beam-based method for measuring the longitudinal impedance spectrum is demonstrated using experimental data from the PEP-II High Energy Ring (HER). The method uses a digital longitudinal feedback system from which the charge and synchronous phase are measured for every bucket. Calculation of the transfer function from fill shape to synchronous phase yields the impedance seen by the beam at revolution harmonics. The experimentally-derived longitudinal impedance function and lab measurements of the impedance of parked RF cavities are compared to suggest a mechanism for the occasional instability of low-order coupled bunch modes observed in the HER during commissioning in October 1997

Experimental study on reactivity measurement in thermal reactor by polarity correlation method

International Nuclear Information System (INIS)

Yasuda, Hideshi

1977-11-01

Experimental study on the polarity correlation method for measuring the reactivity of a thermal reactor, especially the one possessing long prompt neutron lifetime such as graphite on heavy water moderated core, is reported. The techniques of reactor kinetics experiment are briefly reviewed, which are classified in two groups, one characterized by artificial disturbance to a reactor and the other by natural fluctuation inherent in a reactor. The fluctuation phenomena of neutron count rate are explained using F. de Hoffman's stochastic method, and correlation functions for the neutron count rate fluctuation are shown. The experimental results by polarity correlation method applied to the β/l measurements in both graphite-moderated SHE core and light water-moderated JMTRC and JRR-4 cores, and also to the measurement of SHE shut down reactivity margin are presented. The measured values were in good agreement with those by a pulsed neutron method in the reactivity range from critical to -12 dollars. The conditional polarity correlation experiments in SHE at -20 cent and -100 cent are demonstrated. The prompt neutron decay constants agreed with those obtained by the polarity correlation experiments. The results of experiments measuring large negative reactivity of -52 dollars of SHE by pulsed neutron, rod drop and source multiplication methods are given. Also it is concluded that the polarity and conditional polarity correlation methods are sufficiently applicable to noise analysis of a low power thermal reactor with long prompt neutron lifetime. (Nakai, Y.)

Synergy between experimental and theoretical methods in the exploration of homogeneous transition metal catalysis

DEFF Research Database (Denmark)

Lupp, Daniel; Christensen, Niels Johan; Fristrup, Peter

2014-01-01

n this Perspective, we will focus on the use of both experimental and theoretical methods in the exploration of reaction mechanisms in homogeneous transition metal catalysis. We briefly introduce the use of Hammett studies and kinetic isotope effects (KIE). Both of these techniques can be complem......n this Perspective, we will focus on the use of both experimental and theoretical methods in the exploration of reaction mechanisms in homogeneous transition metal catalysis. We briefly introduce the use of Hammett studies and kinetic isotope effects (KIE). Both of these techniques can...... be complemented by computational chemistry – in particular in cases where interpretation of the experimental results is not straightforward. The good correspondence between experiment and theory is only possible due to recent advances within the applied theoretical framework. We therefore also highlight...

Influence of experimental methods on crossing in magnetic force-gap hysteresis curve of HTS maglev system

Energy Technology Data Exchange (ETDEWEB)

Lu Yiyun, E-mail: luyiyun6666@vip.sohu.co [Luoyang Institute of Science and Technology, Luoyang, Henan 471023 (China); Qin Yujie; Dang Qiaohong [Luoyang Institute of Science and Technology, Luoyang, Henan 471023 (China); Wang Jiasu [Applied Superconductivity Laboratory, Southwest Jiaotong University, P.O. Box 152, Chengdu, Sichuan 610031 (China)

2010-12-01

The crossing in magnetic levitation force-gap hysteresis curve of melt high-temperature superconductor (HTS) vs. NdFeB permanent magnet (PM) was experimentally studied. One HTS bulk and PM was used in the experiments. Four experimental methods were employed combining of high/low speed of movement of PM with/without heat insulation materials (HIM) enclosed respectively. Experimental results show that crossing of the levitation force-gap curve is related to experimental methods. A crossing occurs in the magnetic force-gap curve while the PM moves approaching to and departing from the sample with high or low speed of movement without HIM enclosed. When the PM is enclosed with HIM during the measurement procedures, there is no crossing in the force-gap curve no matter high speed or low speed of movement of the PM. It was found experimentally that, with the increase of the moving speed of the PM, the maximum magnitude of levitation force of the HTS increases also. The results are interpreted based on Maxwell theories and flux flow-creep models of HTS.

Influence of experimental methods on crossing in magnetic force-gap hysteresis curve of HTS maglev system

International Nuclear Information System (INIS)

Lu Yiyun; Qin Yujie; Dang Qiaohong; Wang Jiasu

2010-01-01

The crossing in magnetic levitation force-gap hysteresis curve of melt high-temperature superconductor (HTS) vs. NdFeB permanent magnet (PM) was experimentally studied. One HTS bulk and PM was used in the experiments. Four experimental methods were employed combining of high/low speed of movement of PM with/without heat insulation materials (HIM) enclosed respectively. Experimental results show that crossing of the levitation force-gap curve is related to experimental methods. A crossing occurs in the magnetic force-gap curve while the PM moves approaching to and departing from the sample with high or low speed of movement without HIM enclosed. When the PM is enclosed with HIM during the measurement procedures, there is no crossing in the force-gap curve no matter high speed or low speed of movement of the PM. It was found experimentally that, with the increase of the moving speed of the PM, the maximum magnitude of levitation force of the HTS increases also. The results are interpreted based on Maxwell theories and flux flow-creep models of HTS.

Experimental method for testing diffraction properties of reflection waveguide holograms.

Science.gov (United States)

Xie, Yi; Kang, Ming-Wu; Wang, Bao-Ping

2014-07-01

Waveguide holograms' diffraction properties include peak wavelength and diffraction efficiency, which play an important role in determining their display performance. Based on the record and reconstruction theory of reflection waveguide holograms, a novel experimental method for testing diffraction properties is introduced and analyzed in this paper, which uses a plano-convex lens optically contacted to the surface of the substrate plate of the waveguide hologram, so that the diffracted light beam can be easily detected. Then an experiment is implemented. The designed reconstruction wavelength of the test sample is 530 nm, and its diffraction efficiency is 100%. The experimental results are a peak wavelength of 527.7 nm and a diffraction efficiency of 94.1%. It is shown that the tested value corresponds well with the designed value.

Method to deterministically study photonic nanostructures in different experimental instruments

NARCIS (Netherlands)

Husken, B.H.; Woldering, L.A.; Blum, Christian; Tjerkstra, R.W.; Vos, Willem L.

2009-01-01

We describe an experimental method to recover a single, deterministically fabricated nanostructure in various experimental instruments without the use of artificially fabricated markers, with the aim to study photonic structures. Therefore, a detailed map of the spatial surroundings of the

Benzoic acid derivatives: Evaluation of thermochemical properties with complementary experimental and computational methods

International Nuclear Information System (INIS)

Verevkin, Sergey P.; Zaitsau, Dzmitry H.; Emeĺyanenko, Vladimir N.; Stepurko, Elena N.; Zherikova, Kseniya V.

2015-01-01

Highlights: • Vapor pressures of benzoic acid derivatives were measured. • Sublimation enthalpies were derived and compared with the literature. • Thermochemical data tested for consistency using additivity rules and computations. • Contradiction between available enthalpies of sublimation was resolved. • Pairwise interactions of substituents on the benzene ring were derived. - Abstract: Molar sublimation enthalpies of the methyl- and methoxybenzoic acids were derived from the transpiration method, static method, and TGA. Thermochemical data available in the literature were collected, evaluated, and combined with own experimental results. This collection together with the new experimental results reported here has helped to resolve contradictions in the available enthalpy data and to recommend sets of sublimation and formation enthalpies for the benzoic acid derivatives. Gas-phase enthalpies of formation calculated with the G4 quantum-chemical method were in agreement with the experiment. Pairwise interactions of the methyl, methoxy, and carboxyl substituents on the benzene ring were derived and used for the development of simple group-additivity procedures for estimation of the vaporization enthalpies, gas-phase, and liquid-phase enthalpies of formation of substituted benzenes.

Benzoic acid derivatives: Evaluation of thermochemical properties with complementary experimental and computational methods

Energy Technology Data Exchange (ETDEWEB)

Verevkin, Sergey P., E-mail: sergey.verevkin@uni-rostock.de [Department of Physical Chemistry and Department “Science and Technology of Life, Light and Matter”, University of Rostock, D-18059 Rostock (Germany); Department of Physical Chemistry, Kazan Federal University, 420008 Kazan (Russian Federation); Zaitsau, Dzmitry H. [Department of Physical Chemistry, Kazan Federal University, 420008 Kazan (Russian Federation); Emeĺyanenko, Vladimir N. [Department of Physical Chemistry and Department “Science and Technology of Life, Light and Matter”, University of Rostock, D-18059 Rostock (Germany); Stepurko, Elena N. [Chemistry Faculty and Research Institute for Physical Chemical Problems, Belarusian State University, 220030 Minsk (Belarus); Zherikova, Kseniya V. [Nikolaev Institute of Inorganic Chemistry of Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk (Russian Federation)

2015-12-20

Highlights: • Vapor pressures of benzoic acid derivatives were measured. • Sublimation enthalpies were derived and compared with the literature. • Thermochemical data tested for consistency using additivity rules and computations. • Contradiction between available enthalpies of sublimation was resolved. • Pairwise interactions of substituents on the benzene ring were derived. - Abstract: Molar sublimation enthalpies of the methyl- and methoxybenzoic acids were derived from the transpiration method, static method, and TGA. Thermochemical data available in the literature were collected, evaluated, and combined with own experimental results. This collection together with the new experimental results reported here has helped to resolve contradictions in the available enthalpy data and to recommend sets of sublimation and formation enthalpies for the benzoic acid derivatives. Gas-phase enthalpies of formation calculated with the G4 quantum-chemical method were in agreement with the experiment. Pairwise interactions of the methyl, methoxy, and carboxyl substituents on the benzene ring were derived and used for the development of simple group-additivity procedures for estimation of the vaporization enthalpies, gas-phase, and liquid-phase enthalpies of formation of substituted benzenes.

Evaluation of in-vehicle HMI using occlusion techniques: experimental results and practical implications.

Science.gov (United States)

Baumann, Martin; Keinath, Andreas; Krems, Josef F; Bengler, Klaus

2004-05-01

Despite the usefulness of new on-board information systems one has to be concerned about the potential distraction effects that they impose on the driver. Therefore, methods and procedures are necessary to assess the visual demand that is connected to the usage of an on-board system. The occlusion-method is considered a strong candidate as a procedure for evaluating display designs with regard to their visual demand. This paper reports results from two experimental studies conducted to further evaluate this method. In the first study, performance in using an in-car navigation system was measured under three conditions: static (parking lot), occlusion (shutter glasses), and driving. The results show that the occlusion-procedure can be used to simulate visual requirements of real traffic conditions. In a second study the occlusion method was compared to a global evaluation criterion based on the total task time. It can be demonstrated that the occlusion method can identify tasks which meet this criterion, but are yet irresolvable under driving conditions. It is concluded that the occlusion technique seems to be a reliable and valid method for evaluating visual and dialogue aspects of in-car information systems.

CISM-Course on Modern Optical Methods in Experimental Solid Mechanics

CERN Document Server

2000-01-01

The book covers the theories and physics of advanced new optical measuring methods and problems of experimental performance, recent achievements in the basic interferometric methods holography, speckle-interferometry, shearography as well as linear/non-linear photoelasticity and photoviscoelasticity, Moiré- and grid-techniques. It deals with theory and application of digital image processing, methods of data recording, data processing and -visualisation, with mathematical/numerical procedures for final evaluation of digitised measured data and the principle of hybrid techniques. It introduces into the new perceptions of methods in experimental solid mechanics and it should encourage scientists to deal intensively with the theories for further developments, and enables practitioners, to understand theory and physics of the new achievements at least and to apply the methods in research als well as in developments in practice.

Methods for the neutronic design of a Supersara experimental loop

International Nuclear Information System (INIS)

Casali, F.; Cepraga, D.

1982-01-01

This paper describes a method for the neutronic design of experimental loops irradiated in D 2 O experimental reactors, like Essor. The calculation approach concerns the definition of a Weigner-Seitz cell where the loop under examination be subjected to the same neutronic conditions as in the actual reactor

Experimental Verification of a Simple Method for Accurate Center of Gravity Determination of Small Satellite Platforms

Directory of Open Access Journals (Sweden)

Dario Modenini

2018-01-01

Full Text Available We propose a simple and relatively inexpensive method for determining the center of gravity (CoG of a small spacecraft. This method, which can be ascribed to the class of suspension techniques, is based on dual-axis inclinometer readings. By performing two consecutive suspensions from two different points, the CoG is determined, ideally, as the intersection between two lines which are uniquely defined by the respective rotations. We performed an experimental campaign to verify the method and assess its accuracy. Thanks to a quantitative error budget, we obtained an error distribution with simulations, which we verified through experimental tests. The retrieved experimental error distribution agrees well with the results predicted through simulations, which in turn lead to a CoG error norm smaller than 2 mm with 95% confidence level.

Method of Increasing Identification Accuracy under Experimental Tests of Dynamic Objects

Directory of Open Access Journals (Sweden)

Y. N. Pavlov

2015-01-01

Full Text Available The work concerns a problem of increasing identification accuracy of linear dynamic systems on the basis of experimental data obtained by applying test signals to the system.The work is aimed at considering a possibility to use the experimentally obtained hodograph counting to determine parameters of this system in a specific context of the linear dynamic system of the second order.An offer was to use a method of harmonious linearization and a described cut method.The type of frequency transfer function of the identified system was assumed as known.It was supposed that when obtaining the frequency characteristics of a real system there are disturbances interfering with experiment as a result of which points of experimentally received hodograph are random displaced.An identification problem solution was searched in a class of the hodograph set by the system model, which had the same type of frequency transfer function, as the type of frequency transfer function of the identified system.The unknown coefficients of frequency transfer function of the system model were searched through minimizing a proximity criterion (measure of the experimentally received hodograph of the system and of the system model hodograph over the entire aggregate of points. One of the authors described this criterion in the earlier publication.The solution to a problem of nonlinear dynamic system identification by the frequency hodograph was reduced to the solution of the system of equations of the rather unknown linear parameters of frequency transfer function of the system model.The program to simulate a process of the pseudo-experimental data, containing random errors, and determine parameters of this system is developed for a dynamic system of the second order.A conducted computing experiment is conducted to estimate an error at which the offered algorithm defines the values of parameters of this system.

Feedback control of a cupola - concepts and experimental results

Energy Technology Data Exchange (ETDEWEB)

Moore, K.L. [Idaho State Univ., Pocatello, ID (United States); Abdelrahman, M.A. [Tenn. Technological Univ., Cookeville, TN (United States); Larsen, E.; Clark, D. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States); King, P. [US Dept. of Energy Albany Research Center, Albany, OR (United States)

1998-10-01

In this paper we present some final results from a research project focused on introducing automatic control to the operation of cupola iron furnaces. The main aim of this research is to improve the operational efficiency and performance of the cupola furnace, an important foundry process used to melt iron. Previous papers have described the development of appropriate control system architectures for the cupola. These results are summarized. Then we describe the experimental results obtained with the U.S. Department of Energy Albany Research Center`s research cupola. First, experimental data is used to calibrate the model, which is taken as a first-order multivariable system with time delay. Then relative gain analysis is used to select loop pairings to be used in a multi-loop controller. The resulting controller pairs meltrate with blast volume, iron temperature with oxygen addition, and carbon composition with percent coke. Special (nonlinear) filters are used to compute meltrate from actual scale readings of the amount of iron produced and to smooth the temperature measurement. The temperature and meltrate loops use single-loop PI control. The composition loop uses a Smith predictor to discount the deadtime associated with mass transport through the furnace. Experimental results validate the conceptual controller design and provide proof-of-concept of the idea of controlling a foundry cupola. Future research directions are discussed, including the concept of an integrated, intelligent industrial process controller, or I{sup 3}PC.

Thermodynamic properties of 1-naphthol: Mutual validation of experimental and computational results

International Nuclear Information System (INIS)

Chirico, Robert D.; Steele, William V.; Kazakov, Andrei F.

2015-01-01

Highlights: • Heat capacities were measured for the temperature range 5 K to 445 K. • Vapor pressures were measured for the temperature range 370 K to 570 K. • Computed and derived properties for ideal gas entropies are in excellent accord. • The enthalpy of combustion was measured and shown to be consistent with reliable literature values. • Thermodynamic consistency analysis revealed anomalous literature data. - Abstract: Thermodynamic properties for 1-naphthol (Chemical Abstracts registry number [90-15-3]) in the ideal-gas state are reported based on both experimental and computational methods. Measured properties included the triple-point temperature, enthalpy of fusion, and heat capacities for the crystal and liquid phases by adiabatic calorimetry; vapor pressures by inclined-piston manometry and comparative ebulliometry; and the enthalpy of combustion of the crystal phase by oxygen bomb calorimetry. Critical properties were estimated. Entropies for the ideal-gas state were derived from the experimental studies for the temperature range 298.15 ⩽ T/K ⩽ 600, and independent statistical calculations were performed based on molecular geometry optimization and vibrational frequencies calculated at the B3LYP/6-31+G(d,p) level of theory. The mutual validation of the independent experimental and computed results is achieved with a scaling factor of 0.975 applied to the calculated vibrational frequencies. This same scaling factor was successfully applied in the analysis of results for other polycyclic molecules, as described in a series of recent articles by this research group. This article reports the first extension of this approach to a hydroxy-aromatic compound. All experimental results are compared with property values reported in the literature. Thermodynamic consistency between properties is used to show that several studies in the literature are erroneous. The enthalpy of combustion for 1-naphthol was also measured in this research, and excellent

Room temperature thin foil SLIM-cut using an epoxy paste: experimental versus theoretical results

International Nuclear Information System (INIS)

Bellanger, Pierre; Serra, Joao; Bouchard, Pierre-Olivier; Bernacki, Marc

2015-01-01

The stress induced lift-off method (SLIM) -cut technique allows the detachment of thin silicon foils using a stress inducing layer. In this work, results of SLIM-cut foils obtained using an epoxy stress inducing layer at room temperature are presented. Numerical analyses were performed in order to study and ascertain the important experimental parameters. The experimental and simulation results are in good agreement. Indeed, large area (5 × 5 cm 2 ) foils were successfully detached at room temperature using an epoxy thickness of 900 μm and a curing temperature of 150 °C. Moreover, three foils (5 × 3 cm 2 ) with thickness 135, 121 and 110 μm were detached from the same monocrystalline substrate. Effective minority carrier lifetimes of 46, 25 and 20 μs were measured using quasi-steady-state photoconductance technique in these foils after iodine ethanol surface passivation. (paper)

Method of vacuum correlation functions: Results and prospects

International Nuclear Information System (INIS)

Badalian, A. M.; Simonov, Yu. A.; Shevchenko, V. I.

2006-01-01

Basic results obtained within the QCD method of vacuum correlation functions over the past 20 years in the context of investigations into strong-interaction physics at the Institute of Theoretical and Experimental Physics (ITEP, Moscow) are formulated Emphasis is placed primarily on the prospects of the general theory developed within QCD by employing both nonperturbative and perturbative methods. On the basis of ab initio arguments, it is shown that the lowest two field correlation functions play a dominant role in QCD dynamics. A quantitative theory of confinement and deconfinement, as well as of the spectra of light and heavy quarkonia, glueballs, and hybrids, is given in terms of these two correlation functions. Perturbation theory in a nonperturbative vacuum (background perturbation theory) plays a significant role, not possessing drawbacks of conventional perturbation theory and leading to the infrared freezing of the coupling constant α s

Influence of different methods of internal bone fixation on characteristics of bone callus in experimental animals

Directory of Open Access Journals (Sweden)

Gajdobranski Đorđe

2014-01-01

Full Text Available Introduction. Correct choice of osteosynthesis method is a very important factor in providing the optimal conditions for appropriate healing of the fracture. There are still disagreements about the method of stabilization of some long bone fractures. Critically observed, no method of fracture fixation is ideal. Each osteosynthesis method has both advantages and weaknesses. Objective. The objective of this study was to compare the results of the experimental application of three different internal fixation methods: plate fixation, intramedullary nail fixation and self-dynamisable internal fixator (SIF. Methods. A series of 30 animals were used (Lepus cuniculus as experimental animals, divided into three groups of ten animals each. Femoral diaphysis of each animal was osteotomized and fixed with one of three implants. Ten weeks later all animals were sacrificed and each specimen underwent histological and biomechanical testing. Results. Histology showed that the healing process with SIF was more complete and bone callus was more mature in comparison to other two methods. During biomechanical investigation (computerized bending stress test, it was documented with high statistical significance that using SIF led to stronger healing ten weeks after the operation. Conclusion. According to the results obtained in this study, it can be concluded that SIF is a suitable method for fracture treatment.

Crack identification method in beam-like structures using changes in experimentally measured frequencies and Particle Swarm Optimization

Science.gov (United States)

Khatir, Samir; Dekemele, Kevin; Loccufier, Mia; Khatir, Tawfiq; Abdel Wahab, Magd

2018-02-01

In this paper, a technique is presented for the detection and localization of an open crack in beam-like structures using experimentally measured natural frequencies and the Particle Swarm Optimization (PSO) method. The technique considers the variation in local flexibility near the crack. The natural frequencies of a cracked beam are determined experimentally and numerically using the Finite Element Method (FEM). The optimization algorithm is programmed in MATLAB. The algorithm is used to estimate the location and severity of a crack by minimizing the differences between measured and calculated frequencies. The method is verified using experimentally measured data on a cantilever steel beam. The Fourier transform is adopted to improve the frequency resolution. The results demonstrate the good accuracy of the proposed technique.

Sodium fires. Progress achieved in research and experimental results

International Nuclear Information System (INIS)

Malet, J.C.; Duverger de Cuy, G.; Casselman, C.; Charpenel, J.; Natta, M.; Devillers, C.

1979-08-01

This paper describes the sodium fire programs undertaken by the CEA's Nuclear Safety Department. Experimental results concerning sodium ignition and combustion, sodium fire suppression, sodium aerosol filtration and sodium-concrete contact reactions are given and the applications of these results in the Super-Phenix reactor is discussed

Experimental Method for Measuring Dust Load on Surfaces in Rooms

DEFF Research Database (Denmark)

Lengweiler, Philip; Nielsen, Peter V.; Moser, Alfred

A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms, there is a n......A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms......, there is a need for better understanding of the mechanism of dust deposition and resuspension. With the presented experimental setup, the dust load on surfaces in a channel can be measured as a function of the environmental and surface conditions and the type of particles under controlled laboratory conditions....

A flashing driven moderator cooling system for CANDU reactors: Experimental and computational results

International Nuclear Information System (INIS)

Khartabil, H.F.

2000-01-01

A flashing-driven passive moderator cooling system is being developed at AECL for CANDU reactors. Preliminary simulations and experiments showed that the concept was feasible at normal operating power. However, flow instabilities were observed at low powers under conditions of variable and constant calandria inlet temperatures. This finding contradicted code predictions that suggested the loop should be stable at all powers if the calandria inlet temperature was constant. This paper discusses a series of separate-effects tests that were used to identify the sources of low-power instabilities in the experiments, and it explores methods to avoid them. It concludes that low-power instabilities can be avoided, thereby eliminating the discrepancy between the experimental and code results. Two factors were found to be important for loop stability: (1) oscillations in the calandria outlet temperature, and (2) flashing superheat requirements, and the presence of nucleation sites. By addressing these factors, we could make the loop operate in a stable manner over the whole power range and we could obtain good agreement between the experimental and code results. (author)

SiO2-Ta2O5 sputtering yields: simulated and experimental results

International Nuclear Information System (INIS)

Vireton, E.; Ganau, P.; Mackowski, J.M.; Michel, C.; Pinard, L.; Remillieux, A.

1994-09-01

To improve mirrors coating, we have modeled sputtering of binary oxide targets using TRIM code. First, we have proposed a method to calculate TRIM input parameters using on the one hand thermodynamic cycle and on the other hand Malherbe's results. Secondly, an iterative processing has provided for oxide steady targets caused by ionic bombardment. Thirdly, we have exposed a model to get experimental sputtering yields. Fourthly, for (Ar - SiO 2 ) pair, we have determined that steady target is a silica one. A good agreement between simulated and experimental yields versus ion incident angle has been found. For (Ar - Ta 2 O 5 ) pair, we have to introduce preferential sputtering concept to explain discrepancy between simulation and experiment. In this case, steady target is tantalum monoxide. For (Ar - Ta(+O 2 ) pair, tantalum sputtered by argon ions in reactive oxygen atmosphere, we have to take into account new concept of oxidation stimulated by ion beam. We have supposed that tantalum target becomes a Ta 2 O 5 one in reactive oxygen atmosphere. Then, following mechanism is similar to previous pair. We have obtained steady target of tantalum monoxide too. Comparison between simulated and experimental sputtering yields versus ion incident angle has given very good agreement. By simulation, we have found that tantalum monoxide target has at least 15 angstrom thickness. Those results are compatible with Malherbe's and Taglauer's ones. (authors)

Experimental study of self-backlighting method for opacity

International Nuclear Information System (INIS)

Ding Yaonan; Yang Jiamin; Li Sanwei; Cao Leifeng; Wang Yaomei; Zhang Wenhai; Chen Bo; Yu Yanning; Wang Hongbin

2001-01-01

Self-backlighting method for opacity measurement has been suggested and studied, based on the actual condition of Xingguang II laser facility. An 80 J and 350 nm laser, which has a duration of about 700 ps, irradiates on a newly designed target and creates intense X-ray radiation acting as both heating source and backlighter source. The heated sample has been spatially imaged to obtain X-ray spectra from X-ray source region, transmission region and self-emission region of the sample at the same shot by spatially resolved transmission grating spectrometer in which dispersed X-ray is recorded by X-ray CCD. The samples are low-Z CH foam with density of 0.042 g/cm 3 , thickness of 42 μm and mid-Z Al with density of 2.7 g/cm 3 , thickness of 0.5 μm or 1.0 μm. Mass absorption coefficients of the heated sample as function of the photon energy have been obtained experimentally in the same shot. The spectra line emitted from the heated CH foam has also been measured by OHM crystal spectrometer, which has been used to determine the temperature of the sample. The experimental results for opacity of carbon have been discussed

Comparison of leak opening and leak rate calculations to HDR experimental results

International Nuclear Information System (INIS)

Grebner, H.; Hoefler, A.; Hunger, H.

1993-01-01

During the last years a number of calculations of leak opening and leak rate for through cracks in piping components have been performed. Analyses are pre- or mostly post-calculations to experiments performed at the HDR facility under PWR operating conditions. Piping components under consideration were small diameter straight pipes with circumferential cracks, pipe bends with longitudinal or circumferential cracks and pipe branches with weldment cracks. The components were loaded by internal pressure and opening as well as closing bending moment. The finite element method and two-phase flow leak rate programs were used for the calculations. Results of the analyses are presented as J-integral values, crack opening displacements and areas and leak rates as well as comparisons to the experimental results

The experimental field work as practical learning method

Directory of Open Access Journals (Sweden)

Nicolás Fernández Losa

2014-11-01

Full Text Available This paper describes a teaching experience about experimental field work as practical learning method implemented in the subject of Organizational Behaviour. With this teaching experience we pretend to change the practical training, as well as in its evaluation process, in order to favour the development of transversal skills of students. For this purpose, the use of a practice plan, tackled through an experimental field work and carried out with the collaboration of a business organization within a work team (as organic unity of learning, arises as an alternative to the traditional method of practical teachings and allows the approach of business reality into the classroom, as well as actively promote the use of transversal skills. In particular, we develop the experience in three phases. Initially, the students, after forming a working group and define a field work project, should get the collaboration of a nearby business organization in which to obtain data on one or more functional areas of organizational behaviour. Subsequently, students carry out the field work with the realization of the scheduled visits and elaboration of a memory to establish a diagnosis of the strategy followed by the company in these functional areas in order to propose and justify alternative actions that improve existing ones. Finally, teachers assess the different field work memories and their public presentations according to evaluation rubrics, which try to objectify and unify to the maximum the evaluation criteria and serve to guide the learning process of students. The results of implementation of this teaching experience, measured through a Likert questionnaire, are very satisfactory for students.

DoSSiER: Database of Scientific Simulation and Experimental Results

CERN Document Server

Wenzel, Hans; Genser, Krzysztof; Elvira, Daniel; Pokorski, Witold; Carminati, Federico; Konstantinov, Dmitri; Ribon, Alberto; Folger, Gunter; Dotti, Andrea

2017-01-01

The Geant4, GeantV and GENIE collaborations regularly perform validation and regression tests for simulation results. DoSSiER (Database of Scientific Simulation and Experimental Results) is being developed as a central repository to store the simulation results as well as the experimental data used for validation. DoSSiER can be easily accessed via a web application. In addition, a web service allows for programmatic access to the repository to extract records in json or xml exchange formats. In this article, we describe the functionality and the current status of various components of DoSSiER as well as the technology choices we made.

Experimentally increasing sedentary behavior results in decreased life satisfaction

OpenAIRE

Edwards, Meghan K.; Loprinzi, Paul D.

2017-01-01

Background: No study has experimentally manipulated sedentary behavior and evaluated its effect on life satisfaction. Thus, the purpose of this study was to evaluate the effects of a free-living, sedentary behavior-inducing randomized controlled intervention on life satisfaction. Methods: Active, young adults between the ages of 18-35 were recruited and randomly assigned into a sedentary behavior intervention group (n = 26) or a control group (n = 13). The intervention group par...

Experimental innovations in surface science a guide to practical laboratory methods and instruments

CERN Document Server

Yates, John T

2015-01-01

This book is a new edition of a classic text on experimental methods and instruments in surface science. It offers practical insight useful to chemists, physicists, and materials scientists working in experimental surface science. This enlarged second edition contains almost 300 descriptions of experimental methods. The more than 50 active areas with individual scientific and measurement concepts and activities relevant to each area are presented in this book. The key areas covered are: Vacuum System Technology, Mechanical Fabrication Techniques, Measurement Methods, Thermal Control, Delivery of Adsorbates to Surfaces, UHV Windows, Surface Preparation Methods, High Area Solids, Safety. The book is written for researchers and graduate students.

Experimental and numerical investigation of the flow measurement method utilized in the steam generator of HTR-PM

Energy Technology Data Exchange (ETDEWEB)

Wang, Shiming; Ren, Cheng; Sun, Yangfei [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China); Tu, Jiyuan [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China); School of Aerospace, Mechanical & Manufacturing Engineering, RMIT University, Melbourne, VIC 3083 (Australia); Yang, Xingtuan, E-mail: yangxt107@sina.com [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China)

2016-08-15

Highlights: • The flow confluence process in the steam generator is very important for HTR-PM. • The complicated flow in the unique pipeline configuration is studied by both of experimental and numerical method. • The pressure uniformity at the bottom of the model was tested to evaluate the accuracy of the experimental results. • Flow separation and the secondary flow is described for explaining the nonuniformity of the flow distribution. - Abstract: The helium flow measurement method is very important for the design of HTR-PM. Water experiments and numerical simulation with a 1/5 scaled model are conducted to investigate the flow measurement method utilized in the steam generator of HTR-PM. Pressure information at specific location of the 90° elbows with the diameter of 46.75 mm and radius ratio of 1.5 is measured to evaluate the flow rate in the riser-pipes. Pressure uniformity at the bottom of the experimental apparatus is tested to evaluate the influence of the equipment error on the final experimental results. Numerical results obtained by using the realizable k–ε model are compared with the experimental data. The results reveal that flow oscillation does not occur in the confluence system. For every single riser-pipe, the flow is stable despite the nonuniformity of the flow distribution. The average flow rates of the two pipe series show good repeatability regardless of the increases and decreases of the average velocity. In the header box, the flows out of the riser-pipes encounter with each other and finally distort the pressure distribution and the nonuniformity of the flow distribution becomes more significant along with the increasing Reynolds number.

Comparison of calculated and experimental results of fuel bunching in VERA assemblies 1B, 3A and 5A

International Nuclear Information System (INIS)

Matthews, J.D.

1964-12-01

Comparison is made of experimental and calculated reactivity changes when the fuel plates of the VERA assemblies are bunched from 1/8 in. thickness to 1/2 in. In addition, U238 fine structure reaction rates are studied. The method used is that investigated in detail by James and Matthews ('A Perturbation Method for Multigroup Neutron Transport Calculations in Plane Lattices', AEEW - R 219), while the multigroup data sets used are both those of Yiftah, Okrent and Moldauer, and Roach. The method and data give only rough agreement with experimental reactivity changes, with a tendency to over-predict the results. U238 fission rates are in better agreement, though the method predicts too small a variation for the U238 capture rate across a cell. (author)

Experimental research on application of mutual-aid teaching method in technique teaching of university’s football elective course

Directory of Open Access Journals (Sweden)

Wu Jiarong

2016-01-01

Full Text Available With the social development and reform of education system, the quality-oriented education and lifelong education gradually become education reform goals of colleges and universities, the physical education of the higher education and university are also developed. This research adopts the literature data method, ques-tionnaire method, experimental method, mathematical statistics or other methods to do experiments for the stu-dents who take the football elective course (a total of 36 class hours per semester in Zhuhai College of Jilin University with the mutual-aid teaching method. The experimental results show that: First, there is a significant difference between achievements of the specific football technique of the students in the experimental group and the students in the control group (P <0.05; second, in the teaching evaluation, the failure rate of the students in the experimental group significantly reduces, and the pass rate and good rate significantly increases after experi-ment; third, the majority of students accept the mutual-aid teaching method; fourth, the mutual-aid teaching method can be used to significantly improve the learning motivation level of the students.

Method of computer generation and projection recording of microholograms for holographic memory systems: mathematical modelling and experimental implementation

International Nuclear Information System (INIS)

Betin, A Yu; Bobrinev, V I; Evtikhiev, N N; Zherdev, A Yu; Zlokazov, E Yu; Lushnikov, D S; Markin, V V; Odinokov, S B; Starikov, S N; Starikov, R S

2013-01-01

A method of computer generation and projection recording of microholograms for holographic memory systems is presented; the results of mathematical modelling and experimental implementation of the method are demonstrated. (holographic memory)

A Pragmatic Smoothing Method for Improving the Quality of the Results in Atomic Spectroscopy

Science.gov (United States)

Bennun, Leonardo

2017-07-01

A new smoothing method for the improvement on the identification and quantification of spectral functions based on the previous knowledge of the signals that are expected to be quantified, is presented. These signals are used as weighted coefficients in the smoothing algorithm. This smoothing method was conceived to be applied in atomic and nuclear spectroscopies preferably to these techniques where net counts are proportional to acquisition time, such as particle induced X-ray emission (PIXE) and other X-ray fluorescence spectroscopic methods, etc. This algorithm, when properly applied, does not distort the form nor the intensity of the signal, so it is well suited for all kind of spectroscopic techniques. This method is extremely effective at reducing high-frequency noise in the signal much more efficient than a single rectangular smooth of the same width. As all of smoothing techniques, the proposed method improves the precision of the results, but in this case we found also a systematic improvement on the accuracy of the results. We still have to evaluate the improvement on the quality of the results when this method is applied over real experimental results. We expect better characterization of the net area quantification of the peaks, and smaller Detection and Quantification Limits. We have applied this method to signals that obey Poisson statistics, but with the same ideas and criteria, it could be applied to time series. In a general case, when this algorithm is applied over experimental results, also it would be required that the sought characteristic functions, required for this weighted smoothing method, should be obtained from a system with strong stability. If the sought signals are not perfectly clean, this method should be carefully applied

Scaffolded Instruction Improves Student Understanding of the Scientific Method & Experimental Design

Science.gov (United States)

D'Costa, Allison R.; Schlueter, Mark A.

2013-01-01

Implementation of a guided-inquiry lab in introductory biology classes, along with scaffolded instruction, improved students' understanding of the scientific method, their ability to design an experiment, and their identification of experimental variables. Pre- and postassessments from experimental versus control sections over three semesters…

Majorana Thermosyphon Prototype Experimental Results

International Nuclear Information System (INIS)

Fast, James E.; Reid, Douglas J.; Aguayo Navarrete, Estanislao

2010-01-01

The Majorana demonstrator will operate at liquid Nitrogen temperatures to ensure optimal spectrometric performance of its High Purity Germanium (HPGe) detector modules. In order to transfer the heat load of the detector module, the Majorana demonstrator requires a cooling system that will maintain a stable liquid nitrogen temperature. This cooling system is required to transport the heat from the detector chamber outside the shield. One approach is to use the two phase liquid-gas equilibrium to ensure constant temperature. This cooling technique is used in a thermosyphon. The thermosyphon can be designed so the vaporization/condensing process transfers heat through the shield while maintaining a stable operating temperature. A prototype of such system has been built at PNNL. This document presents the experimental results of the prototype and evaluates the heat transfer performance of the system. The cool down time, temperature gradient in the thermosyphon, and heat transfer analysis are studied in this document with different heat load applied to the prototype.

An Experimental Comparison of Two Methods on Photosynthesis Driving Soil Respiration: Girdling and Defoliation.

Science.gov (United States)

Jing, Yanli; Guan, Dexin; Wu, Jiabing; Wang, Anzhi; Jin, Changjie; Yuan, Fenghui

2015-01-01

Previous studies with different experimental methods have demonstrated that photosynthesis significantly influences soil respiration (RS). To compare the experimental results of different methods, RS after girdling and defoliation was measured in five-year-old seedlings of Fraxinus mandshurica from June to September. Girdling and defoliation significantly reduced RS by 33% and 25% within 4 days, and 40% and 32% within the entire treatment period, respectively. The differential response of RS to girdling and defoliation was a result of the over-compensation for RS after girdling and redistribution of stored carbon after defoliation. No significant effect on RS was observed between girdling and defoliation treatment, while the soluble sugar content in fine roots was higher in defoliation than in girdling treatment, indicating that defoliation had less compensation effect for RS after interrupting photosynthates supply. We confirm the close coupling of RS with photosynthesis and recommend defoliation for further studies to estimate the effect of photosynthesis on RS.

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship-Quasi-Experimental Designs.

Science.gov (United States)

Schweizer, Marin L; Braun, Barbara I; Milstone, Aaron M

2016-10-01

Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt, nonrandomized interventions. Quasi-experimental studies can be categorized into 3 major types: interrupted time-series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship, including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. Infect Control Hosp Epidemiol 2016;1-6.

Experimental results on photon-photon interactions at Adone

International Nuclear Information System (INIS)

Baldini Celio, R.; Capon, G.; Fabbro, R. del; Santis, P. de; Grilli, M.; Iarocci, E.; Mencuccini, C.; Murtas, G.P.; Spinetti, M.; Valente, V.; Bacci, C.; Zorzi, C. de; Penso, G.; Stella, B.

1979-01-01

Experimental results for the reactions e + e - →e + e - +X are presented for X=e + e - ,μ + μ - ,π + π - ,eta'. A tagging technique has been used to detect final electrons and positrons. A QED test is performed and an upper limit of 20 keV is derived for the partial width GAMMA(eta'→γγ). (Auth.)

A composite experimental dynamic substructuring method based on partitioned algorithms and localized Lagrange multipliers

Science.gov (United States)

Abbiati, Giuseppe; La Salandra, Vincenzo; Bursi, Oreste S.; Caracoglia, Luca

2018-02-01

Successful online hybrid (numerical/physical) dynamic substructuring simulations have shown their potential in enabling realistic dynamic analysis of almost any type of non-linear structural system (e.g., an as-built/isolated viaduct, a petrochemical piping system subjected to non-stationary seismic loading, etc.). Moreover, owing to faster and more accurate testing equipment, a number of different offline experimental substructuring methods, operating both in time (e.g. the impulse-based substructuring) and frequency domains (i.e. the Lagrange multiplier frequency-based substructuring), have been employed in mechanical engineering to examine dynamic substructure coupling. Numerous studies have dealt with the above-mentioned methods and with consequent uncertainty propagation issues, either associated with experimental errors or modelling assumptions. Nonetheless, a limited number of publications have systematically cross-examined the performance of the various Experimental Dynamic Substructuring (EDS) methods and the possibility of their exploitation in a complementary way to expedite a hybrid experiment/numerical simulation. From this perspective, this paper performs a comparative uncertainty propagation analysis of three EDS algorithms for coupling physical and numerical subdomains with a dual assembly approach based on localized Lagrange multipliers. The main results and comparisons are based on a series of Monte Carlo simulations carried out on a five-DoF linear/non-linear chain-like systems that include typical aleatoric uncertainties emerging from measurement errors and excitation loads. In addition, we propose a new Composite-EDS (C-EDS) method to fuse both online and offline algorithms into a unique simulator. Capitalizing from the results of a more complex case study composed of a coupled isolated tank-piping system, we provide a feasible way to employ the C-EDS method when nonlinearities and multi-point constraints are present in the emulated system.

Literature in Focus: Statistical Methods in Experimental Physics

CERN Multimedia

2007-01-01

Frederick James was a high-energy physicist who became the CERN "expert" on statistics and is now well-known around the world, in part for this famous text. The first edition of Statistical Methods in Experimental Physics was originally co-written with four other authors and was published in 1971 by North Holland (now an imprint of Elsevier). It became such an important text that demand for it has continued for more than 30 years. Fred has updated it and it was released in a second edition by World Scientific in 2006. It is still a top seller and there is no exaggeration in calling it «the» reference on the subject. A full review of the title appeared in the October CERN Courier.Come and meet the author to hear more about how this book has flourished during its 35-year lifetime. Frederick James Statistical Methods in Experimental Physics Monday, 26th of November, 4 p.m. Council Chamber (Bldg. 503-1-001) The author will be introduced...

Preliminary Experimental Results for Indirect Vector-Control of Induction Motor Drives with Forced Dynamics

Directory of Open Access Journals (Sweden)

Jan Vittek

2003-01-01

Full Text Available The contribution presents an extension of indirect vector control of electric drives employing induction motors to 'Forced Dynamic Control'. This method of control offers an accurate realisation of dynamic response profiles, which can be selected by the user. The developed system can be integrated into a drive with a shaft position encoder or a shaft sensoriess drive, in which only the stator currents are measured. The applied stator voltages are determined by a computed inverter switching algorithm. Simulation results and preliminary experimental results for indirect vector control of an idle running induction motor indicate good agreement with the theoretical predictions.

Plant Disease Severity Assessment-How Rater Bias, Assessment Method, and Experimental Design Affect Hypothesis Testing and Resource Use Efficiency.

Science.gov (United States)

Chiang, Kuo-Szu; Bock, Clive H; Lee, I-Hsuan; El Jarroudi, Moussa; Delfosse, Philippe

2016-12-01

The effect of rater bias and assessment method on hypothesis testing was studied for representative experimental designs for plant disease assessment using balanced and unbalanced data sets. Data sets with the same number of replicate estimates for each of two treatments are termed "balanced" and those with unequal numbers of replicate estimates are termed "unbalanced". The three assessment methods considered were nearest percent estimates (NPEs), an amended 10% incremental scale, and the Horsfall-Barratt (H-B) scale. Estimates of severity of Septoria leaf blotch on leaves of winter wheat were used to develop distributions for a simulation model. The experimental designs are presented here in the context of simulation experiments which consider the optimal design for the number of specimens (individual units sampled) and the number of replicate estimates per specimen for a fixed total number of observations (total sample size for the treatments being compared). The criterion used to gauge each method was the power of the hypothesis test. As expected, at a given fixed number of observations, the balanced experimental designs invariably resulted in a higher power compared with the unbalanced designs at different disease severity means, mean differences, and variances. Based on these results, with unbiased estimates using NPE, the recommended number of replicate estimates taken per specimen is 2 (from a sample of specimens of at least 30), because this conserves resources. Furthermore, for biased estimates, an apparent difference in the power of the hypothesis test was observed between assessment methods and between experimental designs. Results indicated that, regardless of experimental design or rater bias, an amended 10% incremental scale has slightly less power compared with NPEs, and that the H-B scale is more likely than the others to cause a type II error. These results suggest that choice of assessment method, optimizing sample number and number of replicate

Numerical and experimental validation of a particle Galerkin method for metal grinding simulation

Science.gov (United States)

Wu, C. T.; Bui, Tinh Quoc; Wu, Youcai; Luo, Tzui-Liang; Wang, Morris; Liao, Chien-Chih; Chen, Pei-Yin; Lai, Yu-Sheng

2018-03-01

In this paper, a numerical approach with an experimental validation is introduced for modelling high-speed metal grinding processes in 6061-T6 aluminum alloys. The derivation of the present numerical method starts with an establishment of a stabilized particle Galerkin approximation. A non-residual penalty term from strain smoothing is introduced as a means of stabilizing the particle Galerkin method. Additionally, second-order strain gradients are introduced to the penalized functional for the regularization of damage-induced strain localization problem. To handle the severe deformation in metal grinding simulation, an adaptive anisotropic Lagrangian kernel is employed. Finally, the formulation incorporates a bond-based failure criterion to bypass the prospective spurious damage growth issues in material failure and cutting debris simulation. A three-dimensional metal grinding problem is analyzed and compared with the experimental results to demonstrate the effectiveness and accuracy of the proposed numerical approach.

Results from the Application of Uncertainty Methods in the CSNI Uncertainty Methods Study (UMS)

International Nuclear Information System (INIS)

Glaeser, H.

2008-01-01

Within licensing procedures there is the incentive to replace the conservative requirements for code application by a - best estimate - concept supplemented by an uncertainty analysis to account for predictive uncertainties of code results. Methods have been developed to quantify these uncertainties. The Uncertainty Methods Study (UMS) Group, following a mandate from CSNI, has compared five methods for calculating the uncertainty in the predictions of advanced -best estimate- thermal-hydraulic codes. Most of the methods identify and combine input uncertainties. The major differences between the predictions of the methods came from the choice of uncertain parameters and the quantification of the input uncertainties, i.e. the wideness of the uncertainty ranges. Therefore, suitable experimental and analytical information has to be selected to specify these uncertainty ranges or distributions. After the closure of the Uncertainty Method Study (UMS) and after the report was issued comparison calculations of experiment LSTF-SB-CL-18 were performed by University of Pisa using different versions of the RELAP 5 code. It turned out that the version used by two of the participants calculated a 170 K higher peak clad temperature compared with other versions using the same input deck. This may contribute to the differences of the upper limit of the uncertainty ranges.

Experimental methods for studying the diffusion of radioactive gases in solids. VII. Sorption method

International Nuclear Information System (INIS)

Bekman, I.N.

1983-01-01

The details of the use of a sorption method in the study of the diffusion of gasses and vapors labeled with radioactive tracers in solids have been considered. Three variants of diffusion systems, which permit the determination of the diffusion coefficient and the solubility constant of gases both from the increase in the amount of diffusate in the sample and from the decrease in its amount in the reservoir, have been tested. Different ways of conducting the experiment have been discussed. A universal method for taking into account the processes of the absorption and scattering of radiation in the material of the sample has been proposed. The experimental results were treated with the aid of a specially developed program package, which is realized on computers of the BESM-6 type. Various mathematical models of the diffusion of gases in solids have been analyzed. Solutions of the diffusion equations under the boundary conditions of the sorption method for the cases of diffusion with trapping, dissociative diffusion, and diffusion in a plate containing spherical inclusions have been obtained. The method has been tested in the example case of the diffusion of a radiative inert gas, viz., radon-22, in low-density polyethylene

Application of evolutionary algorithm methods to polypeptide folding: comparison with experimental results for unsolvated Ac-(Ala-Gly-Gly)5-LysH+

DEFF Research Database (Denmark)

Damsbo, Martin; Kinnear, Brian S; Hartings, Matthew R

2004-01-01

We present an evolutionary method for finding the low-energy conformations of polypeptides. The application, called FOLDAWAY,is based on a generic framework and uses several evolutionary operators as well as local optimization to navigate the complex energy landscape of polypeptides. It maintains...... mobility measurements. It has a flat energy landscape where helical and globular conformations have similar energies. FOLDAWAY locates several large groups of structures not found in previous molecular dynamics simulations for this peptide, including compact globular conformations, which are probably...... two complementary representations of the structures and uses the CHARMM force field for evaluating the energies. The method is applied to unsolvated Met-enkephalin and Ac-(Ala-Gly-Gly)(5)-Lys(+)H(+). Unsolvated Ac-(Ala-Gly-Gly)(5)-Lys(+)H(+) has been the object of recent experimental studies using ion...

The Experimental Study of the Inductive Heating Process by the cleating Method

Directory of Open Access Journals (Sweden)

Dorel Anton HOBLE

2009-05-01

Full Text Available The paper focuses on onemethod of welding of two coaxial cylinders, made ofdifferent materials. The method of welding usesinductive heating technology, and it is based on thedifferent dilatation coefficient of the materials, theinside material has an upper value of the dilatationcoefficient. In the paper it was analyzed the inducedpower density inside the ferromagnetic material, andthe distribution of the temperature field inside thestructure. The theoretical results were utilized tomake an experimental model.

Experimental Study of WBFC method for testing electromagnetic immunity of integrated circuits

OpenAIRE

香川, 直己; カガワ, ナオキ; Naoki, KAGAWA

2004-01-01

The author made a workbench faraday cage, WBFC, in order to estimate performance of the WBFC method for the measurement of common mode noise immunity of integrated circuits. In this report, characteristics of the constructed workbench faraday cage and results of experimental study of effects of the common mode noise on a circuit board including an electronic device are shown. Selected DUT, LM324 is popular operational amplifier for electrical circuits in vehicles.

Fission track dating of volcanic glass: experimental evidence for the validity of the Size-Correction Method

International Nuclear Information System (INIS)

Bernardes, C.; Hadler Neto, J.C.; Lattes, C.M.G.; Araya, A.M.O.; Bigazzi, G.; Cesar, M.F.

1986-01-01

Two techniques may be employed for correcting thermally lowered fission track ages on glass material: the so called 'size-correcting method' and 'Plateau method'. Several results from fission track dating on obsidian were analysed in order to compare the model rising size-correction method with experimental evidences. The results from this work can be summarized as follows: 1) The assumption that mean size of spontaneous and induced etched tracks are equal on samples unaffected by partial fading is supported by experimental results. If reactor effects such as an enhancing of the etching rate in the irradiated fraction due to the radiation damage and/or to the fact that induced fission releases a quantity of energy slightly greater than spontaneous one exist, their influence on size-correction method is very small. 2) The above two correction techniques produce concordant results. 3) Several samples from the same obsidian, affected by 'instantaneous' as well as 'continuous' natural fading to different degrees were analysed: the curve showing decreasing of spontaneous track mean-size vs. fraction of spontaneous tracks lost by fading is in close agreement with the correction curve constructed for the same obsidian by imparting artificial thermal treatements on induced tracks. By the above points one can conclude that the assumptions on which size-correction method is based are well supported, at least in first approximation. (Author) [pt

Gold Nanoparticles as Probes for Nano-Raman Spectroscopy: Preliminary Experimental Results and Modeling

Directory of Open Access Journals (Sweden)

V. Le Nader

2012-01-01

Full Text Available This paper presents an effective Tip-Enhanced Raman Spectrometer (TERS in backscattering reflection configuration. It combines a tip-probe nanopositioning system with Raman spectroscope. Specific tips were processed by anchoring gold nanoparticles on the apex of tapered optical fibers, prepared by an improved chemical etching method. Hence, it is possible to expose a very small area of the sample (~20 nm2 to the very strong local electromagnetic field generated by the lightning rod effect. This experimental configuration was modelled and optimised using the finite element method, which takes into account electromagnetic effects as well as the plasmon resonance. Finally, TERS measurements on single-wall carbon nanotubes were successfully performed. These results confirm the high Raman scattering enhancement predicted by the modelling, induced by our new nano-Raman device.

Molecular hyperpolarizabilities of push–pull chromophores: A comparison between theoretical and experimental results

Energy Technology Data Exchange (ETDEWEB)

Capobianco, A. [Dipartimento di Fisica E.R. Caianiello, Università di Salerno, via ponte don Melillo, I-84084 Fisciano (Italy); Centore, R. [Dipartimento di Chimica P. Corradini, Università di Napoli, via Cintia, I-80126 Napoli (Italy); Noce, C. [Dipartimento di Fisica E.R. Caianiello, Università di Salerno, via ponte don Melillo, I-84084 Fisciano (Italy); Peluso, A., E-mail: apeluso@unisa.it [Dipartimento di Chimica e Biologia, Università di Salerno, via ponte don Melillo, I-84084 Fisciano (Italy)

2013-01-16

Highlights: ► Electro-optical determined and MP2/DFT computed NLO properties have been compared. ► Significant dependence of dipole moments of elongated NLO chromophores on conformations has been found. ► A thorough comparison between MP2 and DFT/TD-DFT computational approaches has been carried out. ► The two-state model overestimates hyperpolarizability. - Abstract: Electric dipole moments and static first order hyperpolarizabilities of two push–pull molecules with an extended π electron systems have been evaluated at different computational levels and compared with the results of electro-optical absorption measurements, based on the two state model. Calculations show that: (i) the dipole moments of such elongated systems depend significantly on conformation, a thorough conformational search is necessary for a meaningful comparison between theoretical and experimental results; (ii) DFT methods, in particular CAM-B3LYP and M05-2X, yield dipole moments which compare well with those obtained by post Hartree–Fock methods (MP2) and by EOA measurements; (iii) theoretical first order hyperpolarizabilities are largely underestimated, both by MP2 and DFT methods, possibly because of the failure of two state model used in electro-optical measurements.

Experimental methods of reactor physics; Methodes experimentales de physique des reacteurs a neutrons thermiques

Energy Technology Data Exchange (ETDEWEB)

Breton, D; Lafore, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-01

This paper is a synthesis of various experimental methods in use with the reactors of the Commissariat a l'Energie Atomique. The main techniques used are mentioned and the difficulties encountered and the accuracy obtained are particularly dwelt upon. The application of these various methods to reactors in order to obtain specific results is also indicated. This paper consists of five parts. I - General methods. Macroscopic and microscopic flux distribution (anisotropy effect), power distribution, etc... II - Kinetic measurements a) pulsed neutron technique: apparatus and accuracy; application to {lambda}t and to anti reactivity measurements; application to graphite, light water and beryllium oxide. b) oscillation techniques: equipment and accuracy; application to the measurements of effective cross sections and resonance integrals. c) fluctuations: apparatus and technique of measurement. III - Poison methods. Description of methods for introducing and extracting the poison, difficulties encountered with light and heavy water, measurement of temperature coefficients and anti-reactivity. IV - Spectra measurements. Choice and development of foils, problems of measurement, application to spectral measurements for thermalization studies, application to dosimetry. V - Experimental shielding measurements. The technique and apparatus recently developed in this field are presented. (authors) [French] Cette communication fait une synthese des differentes methodes experimentales mises en oeuvre sur les reacteurs du CEA. Elle presente les principales techniques utilisees et insiste plus particulierement sur les difficultes rencontrees et la precision obtenue; elle indique egalement l'application de ces differentes methodes sur les reacteurs, en vue de l'obtention des resultats determines. Elle comporte cinq parties: I - METHODES GENERALES: Distribution de flux macroscopique et microscopique (effet d'anisotropie), distribution de puissance, etc... II - MESURES CINETIQUES: a

Experimental substantiation of methodic of 11-13 years old boxers’ coordination development

Directory of Open Access Journals (Sweden)

Yong Qiang Liu

2015-06-01

Full Text Available Purpose: experimental substantiation of methodic of junior boxers’ coordination training. Material: in the research 18 boxers of 11-13 year old age participated. In total, during 4 months 42 trainings were conducted. Total time of coordination load’s fulfillment at each training was 15-45 minutes. Results: dynamic of results in control tests was statistically confident in the tested parameters of movements. It proves effectiveness of usage the tasks with complex-coordination orientation, accented on impact on sensor-informational and motor systems of movements in junior boxers’ trainings. Conclusions: coordination training in boxing at initial stage shall include specialized varied means and methods, which would facilitate formation of motor condition and skills’ basis. Motor condition and skills are a reserve for further rising of coordination abilities’ level of junior sportsmen.

Algorithmic and experimental methods in algebra, geometry, and number theory

CERN Document Server

Decker, Wolfram; Malle, Gunter

2017-01-01

This book presents state-of-the-art research and survey articles that highlight work done within the Priority Program SPP 1489 “Algorithmic and Experimental Methods in Algebra, Geometry and Number Theory”, which was established and generously supported by the German Research Foundation (DFG) from 2010 to 2016. The goal of the program was to substantially advance algorithmic and experimental methods in the aforementioned disciplines, to combine the different methods where necessary, and to apply them to central questions in theory and practice. Of particular concern was the further development of freely available open source computer algebra systems and their interaction in order to create powerful new computational tools that transcend the boundaries of the individual disciplines involved.  The book covers a broad range of topics addressing the design and theoretical foundations, implementation and the successful application of algebraic algorithms in order to solve mathematical research problems. It off...

First experimental results on CMOS Integrated Nickel Electroplated Resonators

DEFF Research Database (Denmark)

Yalcinkaya, Arda Deniz; Hansen, Ole

2004-01-01

This paper presents experimental results on MEMS metallic add-on post-fabrication effects on complementary metal oxide semiconductor (CMOS) transistors. Two versions of add-on processing, that use either e-beam evaporation or magnetron sputtering, are compared through investigation of the electri...

Application of Statistical Methods to Activation Analytical Results near the Limit of Detection

DEFF Research Database (Denmark)

Heydorn, Kaj; Wanscher, B.

1978-01-01

Reporting actual numbers instead of upper limits for analytical results at or below the detection limit may produce reliable data when these numbers are subjected to appropriate statistical processing. Particularly in radiometric methods, such as activation analysis, where individual standard...... deviations of analytical results may be estimated, improved discrimination may be based on the Analysis of Precision. Actual experimental results from a study of the concentrations of arsenic in human skin demonstrate the power of this principle....

A new experimental design method to optimize formulations focusing on a lubricant for hydrophilic matrix tablets.

Science.gov (United States)

Choi, Du Hyung; Shin, Sangmun; Khoa Viet Truong, Nguyen; Jeong, Seong Hoon

2012-09-01

A robust experimental design method was developed with the well-established response surface methodology and time series modeling to facilitate the formulation development process with magnesium stearate incorporated into hydrophilic matrix tablets. Two directional analyses and a time-oriented model were utilized to optimize the experimental responses. Evaluations of tablet gelation and drug release were conducted with two factors x₁ and x₂: one was a formulation factor (the amount of magnesium stearate) and the other was a processing factor (mixing time), respectively. Moreover, different batch sizes (100 and 500 tablet batches) were also evaluated to investigate an effect of batch size. The selected input control factors were arranged in a mixture simplex lattice design with 13 experimental runs. The obtained optimal settings of magnesium stearate for gelation were 0.46 g, 2.76 min (mixing time) for a 100 tablet batch and 1.54 g, 6.51 min for a 500 tablet batch. The optimal settings for drug release were 0.33 g, 7.99 min for a 100 tablet batch and 1.54 g, 6.51 min for a 500 tablet batch. The exact ratio and mixing time of magnesium stearate could be formulated according to the resulting hydrophilic matrix tablet properties. The newly designed experimental method provided very useful information for characterizing significant factors and hence to obtain optimum formulations allowing for a systematic and reliable experimental design method.

Quantitative comparison between theoretical predictions and experimental results for the BCS-BEC crossover

International Nuclear Information System (INIS)

Perali, A.; Pieri, P.; Strinati, G.C.

2004-01-01

Theoretical predictions for the Bardeen-Cooper-Schrieffer-Bose-Einstein condensation crossover of trapped Fermi atoms are compared with recent experimental results for the density profiles of L 6 i. The calculations rest on a single theoretical approach that includes pairing fluctuations beyond mean-field. Excellent agreement with experimental results is obtained. Theoretical predictions for the zero-temperature chemical potential and gap at the unitarity limit are also found to compare extremely well with Quantum Monte Carlo simulations and with recent experimental results

Experimental Quasi-Microwave Whole-Body Averaged SAR Estimation Method Using Cylindrical-External Field Scanning

Science.gov (United States)

Kawamura, Yoshifumi; Hikage, Takashi; Nojima, Toshio

The aim of this study is to develop a new whole-body averaged specific absorption rate (SAR) estimation method based on the external-cylindrical field scanning technique. This technique is adopted with the goal of simplifying the dosimetry estimation of human phantoms that have different postures or sizes. An experimental scaled model system is constructed. In order to examine the validity of the proposed method for realistic human models, we discuss the pros and cons of measurements and numerical analyses based on the finite-difference time-domain (FDTD) method. We consider the anatomical European human phantoms and plane-wave in the 2GHz mobile phone frequency band. The measured whole-body averaged SAR results obtained by the proposed method are compared with the results of the FDTD analyses.

The experimental learning method for environmental education (Tamet in students from the National University of Central Perú

Directory of Open Access Journals (Sweden)

Rosa Haydeé Zárate Quiñones

2016-06-01

Full Text Available This research was conducted in order to apply the experimental method of learning for Sustainable Development in students of the Faculty of Forestry and Environmental Sciences of the National University of Central Peru. For its development we worked with a sample of 1062 students and a quasi-experimental design was used. Were employed different methods of mathematical theoretical, empirical and statistical level that allowed data collection, analysis and interpretation of results. A test of knowledge in Environmental Education for Sustainable Development to students, a questionnaire of perception and opinion, as well as a questionnaire of teacher training was applied. The experimental method used allowed the development of knowledge, habits and environmental values for sustainable development in students, contributing to the protection and conservation of the environment.

New computational and experimental methods for determining the elastic and strength characteristics of materials and for predicting the behavior of structures

Science.gov (United States)

Lyukshin, B. A.; Barashkov, V. N.; Gerasimov, A. V.; Elkin, E. E.; Likhachev, V. N.; Mudarisov, Sh. Sh.; Cherepanov, O. I.

1993-04-01

Experimental methods for determining the physicomechanical characteristics of powder, polymer, and composite materials under thermal-force static and dynamic loads are presented. The results of the experimental investigations are used in numerical methods for calculating the stress — strain state and the stability and for describing the supercritical behavior as well as in methods for efficient design of strong machine-building structures made from new constructional materials.

Validation of Code ASTEC with LIVE-L1 Experimental Results

International Nuclear Information System (INIS)

Bachrata, Andrea

2008-01-01

The severe accidents with core melting are considered at the design stage of project at Generation 3+ of Nuclear Power Plants (NPP). Moreover, there is an effort to apply the severe accident management to the operated NPP. The one of main goals of severe accidents mitigation is corium localization and stabilization. The two strategies that fulfil this requirement are: the in-vessel retention (e.g. AP-600, AP- 1000) and the ex-vessel retention (e.g. EPR). To study the scenario of in-vessel retention, a large experimental program and the integrated codes have been developed. The LIVE-L1 experimental facility studied the formation of melt pools and the melt accumulation in the lower head using different cooling conditions. Nowadays, a new European computer code ASTEC is being developed jointly in France and Germany. One of the important steps in ASTEC development in the area of in-vessel retention of corium is its validation with LIVE-L1 experimental results. Details of the experiment are reported. Results of the ASTEC (module DIVA) application to the analysis of the test are presented. (author)

Perturbation method for experimental determination of neutron spatial distribution in the reactor cell

International Nuclear Information System (INIS)

Takac, S.M.

1972-01-01

The method is based on perturbation of the reactor cell from a few up to few tens of percent. Measurements were performed for square lattice calls of zero power reactors Anna, NORA and RB, with metal uranium and uranium oxide fuel elements, water, heavy water and graphite moderators. Character and functional dependence of perturbations were obtained from the experimental results. Zero perturbation was determined by extrapolation thus obtaining the real physical neutron flux distribution in the reactor cell. Simple diffusion theory for partial plate cell perturbation was developed for verification of the perturbation method. The results of these calculation proved that introducing the perturbation sample in the fuel results in flattening the thermal neutron density dependent on the amplitude of the applied perturbation. Extrapolation applied for perturbed distributions was found to be justified

OIL DECONTAMINATION OF BOTTOM SEDIMENTS EXPERIMENTAL WORK RESULTS

Directory of Open Access Journals (Sweden)

Lushnikov Sergey V.

2006-08-01

Full Text Available This article presents the results of experimental work during 2004-2005 on oil decontamination of bottom sediments of Lake Schuchye, situated in the Komi Republic (Northern Russia. The cause of thecontamination were huge oil spills occurred after a series of accidental ruptures on the Harjaga-Usinsk and Vozej-Usinsk oil-pipe lines in 1994. Flotation technology was used for the cleaning of bottom sediments.157 tons of crude oil were removed during the course of 2-year experimental work from an area of 4,1 ha.The content of aliphatic and alicyclic oil hydrocarbons was reduced from 53,3 g/kg to 2,2 g/kg, on average.Hydrobiological investigations revealed that bottom sediments started to be inhabited by benthos organisms, dominantly Oligochaeta. Besides Oligochaeta, Chironomidae maggots and Bivalvia were detected. Theappearance of Macrozoobenthos organisms can serve as a bioindicator of water quality.

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship – Quasi-Experimental Designs

Science.gov (United States)

Schweizer, Marin L.; Braun, Barbara I.; Milstone, Aaron M.

2016-01-01

Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt non-randomized interventions. Quasi-experimental studies can be categorized into three major types: interrupted time series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. PMID:27267457

An experimental method for the optimization of anti-Compton spectrometer

CERN Document Server

Badran, H M

1999-01-01

The reduction of the Compton continuum can be achieved using a Compton suppression shield. For the first time, an experimental method is purposed for estimating the optimum dimensions of such a shield. The method can also provide information on the effect of the air gap, source geometry, gamma-ray energy, etc., on the optimum dimension of the active shield. The method employs the measurements of the Compton suppression efficiency in two dimensions using small size scintillation detectors. Two types of scintillation materials; NaI(Tl) and NE-102A plastic scintillators, were examined. The effect of gamma-ray energy and source geometry were also investigated using sup 1 sup 3 sup 7 Cs and sup 6 sup 0 Co sources with three geometries; point, cylindrical, and Marinelli shapes. The results indicate the importance of both NaI(Tl) and NE-102A guard detectors in surrounding the main detector rather than the distance above it. The ratio between the part of the guard detector above the surface of the main detector to th...

An experimental-numerical method for comparative analysis of joint prosthesis

International Nuclear Information System (INIS)

Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

2001-01-01

The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs

Sodium cleaning and disposal methods in experimental facilities

International Nuclear Information System (INIS)

Rajan, K.K.; Gurumoorthy, K.; Rajan, M.; Kale, R.D.

1997-01-01

At Indira Gandhi Centre for Atomic Research, major sodium facilities are designed and operated at Engineering Development Group as a part of development programme towards experimental and Prototype Fast Reactor. After the test programme many equipment and components were removed from the sodium facilities and sodium removal and disposal was carried out. The experience gained in different cleaning methods and waste sodium disposal are discussed. (author)

Experimental method for investigating γd→pn photodisintegration reaction on the linearly polarized photon beam of the Erevan synchrotron

International Nuclear Information System (INIS)

Agababyan, K.Sh.; Adamyan, F.V.; Ajrapetyan, A.V.

1985-01-01

The experimental method for measuring the asymmetry of the γd → pn photodisintegration reaction on the linearly polarized photon beam of the Erevan synchrotron is described. The results of Monte Carlo calculations, the calibration of apparatus, the procedure of measurements and experimental data processing are repored

Disorder Prediction Methods, Their Applicability to Different Protein Targets and Their Usefulness for Guiding Experimental Studies

Directory of Open Access Journals (Sweden)

Jennifer D. Atkins

2015-08-01

Full Text Available The role and function of a given protein is dependent on its structure. In recent years, however, numerous studies have highlighted the importance of unstructured, or disordered regions in governing a protein’s function. Disordered proteins have been found to play important roles in pivotal cellular functions, such as DNA binding and signalling cascades. Studying proteins with extended disordered regions is often problematic as they can be challenging to express, purify and crystallise. This means that interpretable experimental data on protein disorder is hard to generate. As a result, predictive computational tools have been developed with the aim of predicting the level and location of disorder within a protein. Currently, over 60 prediction servers exist, utilizing different methods for classifying disorder and different training sets. Here we review several good performing, publicly available prediction methods, comparing their application and discussing how disorder prediction servers can be used to aid the experimental solution of protein structure. The use of disorder prediction methods allows us to adopt a more targeted approach to experimental studies by accurately identifying the boundaries of ordered protein domains so that they may be investigated separately, thereby increasing the likelihood of their successful experimental solution.

Resonant pickups for non-destructive single-particle detection in heavy-ion storage rings and first experimental results

Energy Technology Data Exchange (ETDEWEB)

Sanjari, Mohammad Shahab

2013-04-26

Nuclear astrophysics studies on highly charged radionuclides benefit from accelerator facilities with storage rings, where exotic nuclides produced with small yields can be efficiently investigated. Currently there are two accelerator facilities capable of storing highly charged heavy ions, GSI in Darmstadt and IMP in Lanzhou. Non-destructive detection methods are often used for in-flight measurements based on frequency analysis. The sensitivity of such detection systems are of primary importance specially when number of stored ions is small. Furthermore, since the exotic nuclides of interest are as a rule short-lived, the detectors must be fast. One common form of such detectors are parallel plate SCHOTTKY monitors, on which particles induce a mirror charge at each passage. This method has been successfully used at ESR experimental storage ring of GSI since 1991. In this work we describe a new resonant SCHOTTKY pickup operating as a high sensitive cavity current monitor which was mounted and commissioned in the ESR early 2010. It was successfully used in several storage ring experiments. A very similar pickup was mounted in CSRe at IMP Lanzhou in 2011. First in-ring tests have been performed and new experimental results are pending. The spectral analysis of acquired signals by the new detector has enabled a broad range of new physics experiments. The theory of operation and first experimental results and future perspectives are presented in this thesis.

Resonant pickups for non-destructive single-particle detection in heavy-ion storage rings and first experimental results

International Nuclear Information System (INIS)

Sanjari, Mohammad Shahab

2013-01-01

Nuclear astrophysics studies on highly charged radionuclides benefit from accelerator facilities with storage rings, where exotic nuclides produced with small yields can be efficiently investigated. Currently there are two accelerator facilities capable of storing highly charged heavy ions, GSI in Darmstadt and IMP in Lanzhou. Non-destructive detection methods are often used for in-flight measurements based on frequency analysis. The sensitivity of such detection systems are of primary importance specially when number of stored ions is small. Furthermore, since the exotic nuclides of interest are as a rule short-lived, the detectors must be fast. One common form of such detectors are parallel plate SCHOTTKY monitors, on which particles induce a mirror charge at each passage. This method has been successfully used at ESR experimental storage ring of GSI since 1991. In this work we describe a new resonant SCHOTTKY pickup operating as a high sensitive cavity current monitor which was mounted and commissioned in the ESR early 2010. It was successfully used in several storage ring experiments. A very similar pickup was mounted in CSRe at IMP Lanzhou in 2011. First in-ring tests have been performed and new experimental results are pending. The spectral analysis of acquired signals by the new detector has enabled a broad range of new physics experiments. The theory of operation and first experimental results and future perspectives are presented in this thesis.

Acquiring molecular interference functions of X-ray coherent scattering for breast tissues by combination of simulation and experimental methods

International Nuclear Information System (INIS)

Chaparian, A.; Oghabian, M. A.; Changizi, V.

2009-01-01

Recently, it has been indicated that X-ray coherent scatter from biological tissues can be used to access signature of tissue. Some scientists are interested in studying this effect to get early detection of breast cancer. Since experimental methods for optimization are time consuming and expensive, some scientists suggest using simulation. Monte Carlo codes are the best option for radiation simulation: however, one permanent defect with Monte Carlo codes has been the lack of a sufficient physical model for coherent (Rayleigh) scattering, including molecular interference effects. Materials and Methods: It was decided to obtain molecular interference functions of coherent X-ray scattering for normal breast tissues by combination of modeling and experimental methods. A Monte Carlo simulation program was written to simulate the angular distribution of scattered photons for the normal breast tissue samples. Moreover, experimental diffraction patterns of these tissues were measured by means of energy dispersive X-ray diffraction method. The simulation and experimental data were used to obtain a tabulation of molecular interference functions for breast tissues. Results: With this study a tabulation of molecular interference functions for normal breast tissues Was prepared to facilitate the simulation diffraction patterns of the tissues without any experimental. Conclusion: The method may lead to design new systems for early detection of breast cancer.

A semantics-based method for clustering of Chinese web search results

Science.gov (United States)

Zhang, Hui; Wang, Deqing; Wang, Li; Bi, Zhuming; Chen, Yong

2014-01-01

Information explosion is a critical challenge to the development of modern information systems. In particular, when the application of an information system is over the Internet, the amount of information over the web has been increasing exponentially and rapidly. Search engines, such as Google and Baidu, are essential tools for people to find the information from the Internet. Valuable information, however, is still likely submerged in the ocean of search results from those tools. By clustering the results into different groups based on subjects automatically, a search engine with the clustering feature allows users to select most relevant results quickly. In this paper, we propose an online semantics-based method to cluster Chinese web search results. First, we employ the generalised suffix tree to extract the longest common substrings (LCSs) from search snippets. Second, we use the HowNet to calculate the similarities of the words derived from the LCSs, and extract the most representative features by constructing the vocabulary chain. Third, we construct a vector of text features and calculate snippets' semantic similarities. Finally, we improve the Chameleon algorithm to cluster snippets. Extensive experimental results have shown that the proposed algorithm has outperformed over the suffix tree clustering method and other traditional clustering methods.

Experimental method for laser-driven flyer plates for 1-D shocks

International Nuclear Information System (INIS)

Paisley, D. L.; Luo, S. N.; Swift, D. C.; Loomis, E.; Johnson, R.; Greenfield, S.; Peralta, P.; Koskelo, A.; Tonks, D.

2007-01-01

One-dimensional shocks can be generated by impacting flyer plates accelerated to terminal velocities by a confined laser-ablated plasma. Over the past few years, we have developed this capability with our facility-size laser, TRIDENT, capable of ≥500 Joules at multi-microsecond pulse lengths to accelerate 1-D flyer plates, 8-mm diameter by 0.1-2 mm thick. Plates have been accelerated to terminal velocities of 100 to ≥500 m/s, with full recovery of the flyer and target for post mortem metallography. By properly tailoring the laser temporal and spatial profile, the expanding confined plasma accelerates the plate away from the transparent sapphire substrate, and decouples the laser parameters from shock pressure profile resulting from the plate impact on a target. Since the flyer plate is in free flight on impact with the target, minimal collateral damage occurs to either. The experimental method to launch these plates to terminal velocity, ancillary diagnostics, and representative experimental data is presented

Experimental facility and void fraction calibration methods for impedance probes

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Fernando L. de; Rocha, Marcelo S., E-mail: floliveira@ipen.br, E-mail: msrocha@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

An experimental facility was designed and constructed with aims of to calibrate a capacitance probe for gas-liquid flow void fraction measurements. The facility is composed of a metallic hack with a vertical 2,300 mm high glass tube with 38 mm ID with stagnant water and compressed air bubbling system simulating the gas phase (vapor). At the lower part, a mixing section with a porous media element releases the air bubbles into the water, and the compressed air flow is measured by two calibrated rotameters. At the upper part a stagnant water tank separates the liquid and gas. Two pressure taps are located near the lower and upper sides of the glass tube for pressure difference measurement. The pressure difference is used for low void fraction values (0-15%) calibration methods, as described in the work. Two electrically controlled quick closing valves are installed between the porous media element and the upward separation tank for high void fraction values measurement (15-50%) used to calibrate the capacitance probe. The experimental facility design, construction, capacitance probe calibration methods and results, as well as flow pattern visualization, are presented. Finally, the capacitance probe will be installed on a natural circulation circuit mounted at the Nuclear Engineering Center (CEN/IPEN/CNEN-SP) for measurement of the instantaneous bulk void. Instantaneous signals generated by the capacitance probe will allow the determination of natural circulation loop global energy balance. (author)

Experimental facility and void fraction calibration methods for impedance probes

International Nuclear Information System (INIS)

Oliveira, Fernando L. de; Rocha, Marcelo S.

2013-01-01

An experimental facility was designed and constructed with aims of to calibrate a capacitance probe for gas-liquid flow void fraction measurements. The facility is composed of a metallic hack with a vertical 2,300 mm high glass tube with 38 mm ID with stagnant water and compressed air bubbling system simulating the gas phase (vapor). At the lower part, a mixing section with a porous media element releases the air bubbles into the water, and the compressed air flow is measured by two calibrated rotameters. At the upper part a stagnant water tank separates the liquid and gas. Two pressure taps are located near the lower and upper sides of the glass tube for pressure difference measurement. The pressure difference is used for low void fraction values (0-15%) calibration methods, as described in the work. Two electrically controlled quick closing valves are installed between the porous media element and the upward separation tank for high void fraction values measurement (15-50%) used to calibrate the capacitance probe. The experimental facility design, construction, capacitance probe calibration methods and results, as well as flow pattern visualization, are presented. Finally, the capacitance probe will be installed on a natural circulation circuit mounted at the Nuclear Engineering Center (CEN/IPEN/CNEN-SP) for measurement of the instantaneous bulk void. Instantaneous signals generated by the capacitance probe will allow the determination of natural circulation loop global energy balance. (author)

Laser long-range remote-sensing program experimental results

Science.gov (United States)

Highland, Ronald G.; Shilko, Michael L.; Fox, Marsha J.; Gonglewski, John D.; Czyzak, Stanley R.; Dowling, James A.; Kelly, Brian; Pierrottet, Diego F.; Ruffatto, Donald; Loando, Sharon; Matsuura, Chris; Senft, Daniel C.; Finkner, Lyle; Rae, Joe; Gallegos, Joe

1995-12-01

A laser long range remote sensing (LRS) program is being conducted by the United States Air Force Phillips Laboratory (AF/PL). As part of this program, AF/PL is testing the feasibility of developing a long path CO(subscript 2) laser-based DIAL system for remote sensing. In support of this program, the AF/PL has recently completed an experimental series using a 21 km slant- range path (3.05 km ASL transceiver height to 0.067 km ASL target height) at its Phillips Laboratory Air Force Maui Optical Station (AMOS) facility located on Maui, Hawaii. The dial system uses a 3-joule, (superscript 13)C isotope laser coupled into a 0.6 m diameter telescope. The atmospheric optical characterization incorporates information from an infrared scintillometer co-aligned to the laser path, atmospheric profiles from weather balloons launched from the target site, and meteorological data from ground stations at AMOS and the target site. In this paper, we report a description of the experiment configuration, a summary of the results, a summary of the atmospheric conditions and their implications to the LRS program. The capability of such a system for long-range, low-angle, slant-path remote sensing is discussed. System performance issues relating to both coherent and incoherent detection methods, atmospheric limitations, as well as, the development of advanced models to predict performance of long range scenarios are presented.

Experimental Methods for UAV Aerodynamic and Propulsion Performance Assessment

Directory of Open Access Journals (Sweden)

Stefan ANTON

2015-06-01

Full Text Available This paper presents an experimental method for assessing the performances and the propulsion power of a UAV in several points based on telemetry. The points in which we make the estimations are chosen based on several criteria and the fallowing parameters are measured: airspeed, time-to-climb, altitude and the horizontal distance. With the estimated propulsion power and knowing the shaft motor power, the propeller efficiency is determined at several speed values. The shaft motor power was measured in the lab using the propeller as a break. Many flights, using the same UAV configuration, were performed before extracting flight data, in order to reduce the instrumental or statistic errors. This paper highlights both the methodology of processing the data and the validation of theoretical results.

A Laplace method for under-determined Bayesian optimal experimental designs

KAUST Repository

Long, Quan; Scavino, Marco; Tempone, Raul; Wang, Suojin

2014-01-01

In Long et al. (2013), a new method based on the Laplace approximation was developed to accelerate the estimation of the post-experimental expected information gains (Kullback–Leibler divergence) in model parameters and predictive quantities

Recent mouse and rat methods for the study of experimental oral candidiasis.

Science.gov (United States)

Costa, Anna C B P; Pereira, Cristiane A; Junqueira, Juliana C; Jorge, Antonio O C

2013-07-01

The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis.

Recent mouse and rat methods for the study of experimental oral candidiasis

Science.gov (United States)

Costa, Anna CBP; Pereira, Cristiane A; Junqueira, Juliana C; Jorge, Antonio OC

2013-01-01

The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis. PMID:23715031

An innovative method for coordinate measuring machine one-dimensional self-calibration with simplified experimental process.

Science.gov (United States)

Fang, Cheng; Butler, David Lee

2013-05-01

In this paper, an innovative method for CMM (Coordinate Measuring Machine) self-calibration is proposed. In contrast to conventional CMM calibration that relies heavily on a high precision reference standard such as a laser interferometer, the proposed calibration method is based on a low-cost artefact which is fabricated with commercially available precision ball bearings. By optimizing the mathematical model and rearranging the data sampling positions, the experimental process and data analysis can be simplified. In mathematical expression, the samples can be minimized by eliminating the redundant equations among those configured by the experimental data array. The section lengths of the artefact are measured at arranged positions, with which an equation set can be configured to determine the measurement errors at the corresponding positions. With the proposed method, the equation set is short of one equation, which can be supplemented by either measuring the total length of the artefact with a higher-precision CMM or calibrating the single point error at the extreme position with a laser interferometer. In this paper, the latter is selected. With spline interpolation, the error compensation curve can be determined. To verify the proposed method, a simple calibration system was set up on a commercial CMM. Experimental results showed that with the error compensation curve uncertainty of the measurement can be reduced to 50%.

Investigation on bonding defects in ITER first wall beryllium armour components by combining analytical and experimental methods

Energy Technology Data Exchange (ETDEWEB)

Pérez, Germán, E-mail: german.perez.pichel@gmail.com; Mitteau, Raphaël; Eaton, Russell; Raffray, René

2015-12-15

Highlights: • Bonding defects at the ITER first wall beryllium armour are studied. • Experimental and analytical methods are combined. • Models supporting test results interpretation are proposed. • Guidelines for new experimental protocols are suggested. • Contribution to the definition of defects acceptance criteria. - Abstract: The reliability of the plasma facing components (PFCs) is essential for the efficient plasma operation in a fusion machine. This concerns especially the bond between the armour tiles facing the plasma and the heat sink material (copper alloy). The different thermal expansions of the bonded materials cause a stress distribution in the bond, which peaks at the bond edge. Under cyclic heat flux and accounting for the possible presence of bonding defects, this stress could reach a level where the component might be jeopardised. Because of the complexity of describing realistically by analyses and models the stress evolution in the bond, “design by experiments” is the main procedure for defining and qualifying the armour joint. Most of the existing plasma operation know-how on actively cooled PFCs has been obtained with carbon composite armour tiles. In ITER, the tiles of the first wall are made out of beryllium, which means that the know-how is progressively adapted to this specific bimetallic pair. Nonetheless, analyses are still performed for supporting the R&D experimental programme. This paper: explores methods for combining experimental results with finite element and statistical analyses; benchmarks test results; proposes hypothesis and rationales consistent with test results interpretations; suggests guidelines for defining possible further experimental protocols; and contributes to the definition of defects acceptance criteria.

Investigation on bonding defects in ITER first wall beryllium armour components by combining analytical and experimental methods

International Nuclear Information System (INIS)

Pérez, Germán; Mitteau, Raphaël; Eaton, Russell; Raffray, René

2015-01-01

Highlights: • Bonding defects at the ITER first wall beryllium armour are studied. • Experimental and analytical methods are combined. • Models supporting test results interpretation are proposed. • Guidelines for new experimental protocols are suggested. • Contribution to the definition of defects acceptance criteria. - Abstract: The reliability of the plasma facing components (PFCs) is essential for the efficient plasma operation in a fusion machine. This concerns especially the bond between the armour tiles facing the plasma and the heat sink material (copper alloy). The different thermal expansions of the bonded materials cause a stress distribution in the bond, which peaks at the bond edge. Under cyclic heat flux and accounting for the possible presence of bonding defects, this stress could reach a level where the component might be jeopardised. Because of the complexity of describing realistically by analyses and models the stress evolution in the bond, “design by experiments” is the main procedure for defining and qualifying the armour joint. Most of the existing plasma operation know-how on actively cooled PFCs has been obtained with carbon composite armour tiles. In ITER, the tiles of the first wall are made out of beryllium, which means that the know-how is progressively adapted to this specific bimetallic pair. Nonetheless, analyses are still performed for supporting the R&D experimental programme. This paper: explores methods for combining experimental results with finite element and statistical analyses; benchmarks test results; proposes hypothesis and rationales consistent with test results interpretations; suggests guidelines for defining possible further experimental protocols; and contributes to the definition of defects acceptance criteria.

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

Overview of experimental progress on understanding photon strength functions with an emphasis of the Oslo method

Science.gov (United States)

Krticka, Milan

2015-10-01

The so-called Photon Strength Functions (PSFs) for different multipolarities are, together with the Nuclear Level Density (NLD) the key entities describing the statistical γ-decay of nucleus. It is well known that PSFs at energies above the threshold for particle emission are well described by the Lorentzian shape of the Giant Electric Dipole Resonance (GEDR). On the other hand, shapes of RSFs at the low-energy tail of GEDR are known rather poorly. Information on the PSFs at the GEDR tail can be obtained from several different experimental techniques. They will be summarized and the most important ones briefly introduced in this contribution. Special emphasis will be put on the so-called Oslo method which allows simultaneous extraction of the NLD and the PSFs from particle- γ coincidence measurements. This method has been used for determining the NLD and the PSFs in many nuclei in A ~ 45- 240 range during past years. Examples of the most interesting results obtained with this method will be shown. The results will be compared to information on the PSFs available from other experimental techniques. The strengths and the weaknesses of the method will be thoroughly discussed.

Polarimetric Emission of Rain Events: Simulation and Experimental Results at X-Band

Directory of Open Access Journals (Sweden)

Nuria Duffo

2009-06-01

Full Text Available Accurate models are used today for infrared and microwave satellite radiance simulations of the first two Stokes elements in the physical retrieval, data assimilation etc. of surface and atmospheric parameters. Although in the past a number of theoretical and experimental works have studied the polarimetric emission of some natural surfaces, specially the sea surface roughened by the wind (Windsat mission, very limited studies have been conducted on the polarimetric emission of rain cells or other natural surfaces. In this work, the polarimetric emission (four Stokes elements of a rain cell is computed using the polarimetric radiative transfer equation assuming that raindrops are described by Pruppacher-Pitter shapes and that their size distribution follows the Laws-Parsons law. The Boundary Element Method (BEM is used to compute the exact bistatic scattering coefficients for each raindrop shape and different canting angles. Numerical results are compared to the Rayleigh or Mie scattering coefficients, and to Oguchi’s ones, showing that above 1-2 mm raindrop size the exact formulation is required to model properly the scattering. Simulation results using BEM are then compared to the experimental data gathered with a X-band polarimetric radiometer. It is found that the depolarization of the radiation caused by the scattering of non-spherical raindrops induces a non-zero third Stokes parameter, and the differential phase of the scattering coefficients induces a non-zero fourth Stokes parameter.

[Interactions of DNA bases with individual water molecules. Molecular mechanics and quantum mechanics computation results vs. experimental data].

Science.gov (United States)

Gonzalez, E; Lino, J; Deriabina, A; Herrera, J N F; Poltev, V I

2013-01-01

To elucidate details of the DNA-water interactions we performed the calculations and systemaitic search for minima of interaction energy of the systems consisting of one of DNA bases and one or two water molecules. The results of calculations using two force fields of molecular mechanics (MM) and correlated ab initio method MP2/6-31G(d, p) of quantum mechanics (QM) have been compared with one another and with experimental data. The calculations demonstrated a qualitative agreement between geometry characteristics of the most of local energy minima obtained via different methods. The deepest minima revealed by MM and QM methods correspond to water molecule position between two neighbor hydrophilic centers of the base and to the formation by water molecule of hydrogen bonds with them. Nevertheless, the relative depth of some minima and peculiarities of mutual water-base positions in' these minima depend on the method used. The analysis revealed insignificance of some differences in the results of calculations performed via different methods and the importance of other ones for the description of DNA hydration. The calculations via MM methods enable us to reproduce quantitatively all the experimental data on the enthalpies of complex formation of single water molecule with the set of mono-, di-, and trimethylated bases, as well as on water molecule locations near base hydrophilic atoms in the crystals of DNA duplex fragments, while some of these data cannot be rationalized by QM calculations.

Survey of engineering computational methods and experimental programs for estimating supersonic missile aerodynamic characteristics

Science.gov (United States)

Sawyer, W. C.; Allen, J. M.; Hernandez, G.; Dillenius, M. F. E.; Hemsch, M. J.

1982-01-01

This paper presents a survey of engineering computational methods and experimental programs used for estimating the aerodynamic characteristics of missile configurations. Emphasis is placed on those methods which are suitable for preliminary design of conventional and advanced concepts. An analysis of the technical approaches of the various methods is made in order to assess their suitability to estimate longitudinal and/or lateral-directional characteristics for different classes of missile configurations. Some comparisons between the predicted characteristics and experimental data are presented. These comparisons are made for a large variation in flow conditions and model attitude parameters. The paper also presents known experimental research programs developed for the specific purpose of validating analytical methods and extending the capability of data-base programs.

A photocurrent compensation method of bipolar transistors under high dose rate radiation and its experimental research

International Nuclear Information System (INIS)

Yin Xuesong; Liu Zhongli; Li Chunji; Yu Fang

2005-01-01

Experiment using discrete bipolar transistors has been performed to verify the effect of the photocurrent compensation method. The theory of the dose rate effects of bipolar transistors and the photocurrent compensation method are introduced. The comparison between the response of hardened and unhardened circuits under high dose rate radiation is discussed. The experimental results show instructiveness to the hardness of bipolar integrated circuits under transient radiation. (authors)

Theory, simulation and experimental results of the acoustic detection of magnetization changes in superparamagnetic iron oxide

Directory of Open Access Journals (Sweden)

Borgert Jörn

2011-06-01

Full Text Available Abstract Background Magnetic Particle Imaging is a novel method for medical imaging. It can be used to measure the local concentration of a tracer material based on iron oxide nanoparticles. While the resulting images show the distribution of the tracer material in phantoms or anatomic structures of subjects under examination, no information about the tissue is being acquired. To expand Magnetic Particle Imaging into the detection of soft tissue properties, a new method is proposed, which detects acoustic emissions caused by magnetization changes in superparamagnetic iron oxide. Methods Starting from an introduction to the theory of acoustically detected Magnetic Particle Imaging, a comparison to magnetically detected Magnetic Particle Imaging is presented. Furthermore, an experimental setup for the detection of acoustic emissions is described, which consists of the necessary field generating components, i.e. coils and permanent magnets, as well as a calibrated microphone to perform the detection. Results The estimated detection limit of acoustic Magnetic Particle Imaging is comparable to the detection limit of magnetic resonance imaging for iron oxide nanoparticles, whereas both are inferior to the theoretical detection limit for magnetically detected Magnetic Particle Imaging. Sufficient data was acquired to perform a comparison to the simulated data. The experimental results are in agreement with the simulations. The remaining differences can be well explained. Conclusions It was possible to demonstrate the detection of acoustic emissions of magnetic tracer materials in Magnetic Particle Imaging. The processing of acoustic emission in addition to the tracer distribution acquired by magnetic detection might allow for the extraction of mechanical tissue parameters. Such parameters, like for example the velocity of sound and the attenuation caused by the tissue, might also be used to support and improve ultrasound imaging. However, the method

Experimental Study on the Compressive Strength of Big Mobility Concrete with Nondestructive Testing Method

Directory of Open Access Journals (Sweden)

Huai-Shuai Shang

2012-01-01

Full Text Available An experimental study of C20, C25, C30, C40, and C50 big mobility concrete cubes that came from laboratory and construction site was completed. Nondestructive testing (NDT was carried out using impact rebound hammer (IRH techniques to establish a correlation between the compressive strengths and the rebound number. The local curve for measuring strength of the regression method is set up and its superiority is proved. The rebound method presented is simple, quick, and reliable and covers wide ranges of concrete strengths. The rebound method can be easily applied to concrete specimens as well as existing concrete structures. The final results were compared with previous ones from the literature and also with actual results obtained from samples extracted from existing structures.

Integral method of treatment of experimental data from radiochemical solar neutrino detectors

International Nuclear Information System (INIS)

Gavrin, V.N.; Kopylov, A.V.; Streltsov, A.V.

1985-01-01

An analysis is made of the statistical errors in solar neutrino detection by radiochemical detectors at different times of exposure. It is shown that short exposures (tau/sub e/ = one-half to one half-life) give minimal one-year error. The possibility is considered of the detection of the solar neutrino flux variation due to annual changes of the Earth-Sun distance. The integral method of treatment of the experimental data is described. Results are given of the statistical treatment of computer simulated data

Development of experimental method for self-wastage behavior in sodium-water reaction. Development of test rig (SWAT-2R) and study for experimental procedure

International Nuclear Information System (INIS)

Abe, Yuta; Shimoyama, Kazuhito; Kurihara, Akikazu

2014-07-01

In case of water leak from a penetrated crack on a tube of steam generator in the sodium cooled fast reactor (SFR), self-wastage, that increases the size of leak, may take place by corrosion related to chemical reaction between sodium and water. If the self-wastage continues in a certain period of time, the intact tube bundle may be damaged as a result of enlarged leak. For the safety evaluation of the accident, JAEA has been developing the analytical method of self-wastage using the multi-dimensional sodium-water reaction code. Experiments conducted so far used mainly crack-type test pieces. However, reproducibility was limited and it was difficult to evaluate individual effects of the phenomena in detail. This report describes the development of new experimental rig (SWAT-2R). SWAT-2R enables to examine corrosion effecting factors that were ambiguous in the previous studies. The report includes description of development of micro-leak test piece, examination of experimental procedure. The results will provide fundamental data for validation of the self-wastage analytical method. (author)

Optimal Control of Diesel Engines: Numerical Methods, Applications, and Experimental Validation

Directory of Open Access Journals (Sweden)

Jonas Asprion

2014-01-01

become complex systems. The exploitation of any leftover potential during transient operation is crucial. However, even an experienced calibration engineer cannot conceive all the dynamic cross couplings between the many actuators. Therefore, a highly iterative procedure is required to obtain a single engine calibration, which in turn causes a high demand for test-bench time. Physics-based mathematical models and a dynamic optimisation are the tools to alleviate this dilemma. This paper presents the methods required to implement such an approach. The optimisation-oriented modelling of diesel engines is summarised, and the numerical methods required to solve the corresponding large-scale optimal control problems are presented. The resulting optimal control input trajectories over long driving profiles are shown to provide enough information to allow conclusions to be drawn for causal control strategies. Ways of utilising this data are illustrated, which indicate that a fully automated dynamic calibration of the engine control unit is conceivable. An experimental validation demonstrates the meaningfulness of these results. The measurement results show that the optimisation predicts the reduction of the fuel consumption and the cumulative pollutant emissions with a relative error of around 10% on highly transient driving cycles.

Experimental installation of refrigeration solar-first results; Instalacion experimental de refrigeracion solar-primeros resultados

Energy Technology Data Exchange (ETDEWEB)

Moone, C.; Guallar, J.; Alonso, S.; Palacin, F.

2008-07-01

In this article they are and the first results of an installation of solar refrigeration composed by a field of flat solar collector are analysed and absorption chillers of simple effect (BrLi-H{sub 2}O), used to give cold to a gymnasium of the university sport pavilion. The data correspond to the registered experimental values during the summer of 2007 (months of June, Julio and August). (Author)

SPACE CHARGE SIMULATION METHODS INCORPORATED IN SOME MULTI - PARTICLE TRACKING CODES AND THEIR RESULTS COMPARISON

International Nuclear Information System (INIS)

BEEBE - WANG, J.; LUCCIO, A.U.; D IMPERIO, N.; MACHIDA, S.

2002-01-01

Space charge in high intensity beams is an important issue in accelerator physics. Due to the complicity of the problems, the most effective way of investigating its effect is by computer simulations. In the resent years, many space charge simulation methods have been developed and incorporated in various 2D or 3D multi-particle-tracking codes. It has becoming necessary to benchmark these methods against each other, and against experimental results. As a part of global effort, we present our initial comparison of the space charge methods incorporated in simulation codes ORBIT++, ORBIT and SIMPSONS. In this paper, the methods included in these codes are overviewed. The simulation results are presented and compared. Finally, from this study, the advantages and disadvantages of each method are discussed

SPACE CHARGE SIMULATION METHODS INCORPORATED IN SOME MULTI - PARTICLE TRACKING CODES AND THEIR RESULTS COMPARISON.

Energy Technology Data Exchange (ETDEWEB)

BEEBE - WANG,J.; LUCCIO,A.U.; D IMPERIO,N.; MACHIDA,S.

2002-06-03

Space charge in high intensity beams is an important issue in accelerator physics. Due to the complicity of the problems, the most effective way of investigating its effect is by computer simulations. In the resent years, many space charge simulation methods have been developed and incorporated in various 2D or 3D multi-particle-tracking codes. It has becoming necessary to benchmark these methods against each other, and against experimental results. As a part of global effort, we present our initial comparison of the space charge methods incorporated in simulation codes ORBIT++, ORBIT and SIMPSONS. In this paper, the methods included in these codes are overviewed. The simulation results are presented and compared. Finally, from this study, the advantages and disadvantages of each method are discussed.

Time-oriented experimental design method to optimize hydrophilic matrix formulations with gelation kinetics and drug release profiles.

Science.gov (United States)

Shin, Sangmun; Choi, Du Hyung; Truong, Nguyen Khoa Viet; Kim, Nam Ah; Chu, Kyung Rok; Jeong, Seong Hoon

2011-04-04

A new experimental design methodology was developed by integrating the response surface methodology and the time series modeling. The major purposes were to identify significant factors in determining swelling and release rate from matrix tablets and their relative factor levels for optimizing the experimental responses. Properties of tablet swelling and drug release were assessed with ten factors and two default factors, a hydrophilic model drug (terazosin) and magnesium stearate, and compared with target values. The selected input control factors were arranged in a mixture simplex lattice design with 21 experimental runs. The obtained optimal settings for gelation were PEO, LH-11, Syloid, and Pharmacoat with weight ratios of 215.33 (88.50%), 5.68 (2.33%), 19.27 (7.92%), and 3.04 (1.25%), respectively. The optimal settings for drug release were PEO and citric acid with weight ratios of 191.99 (78.91%) and 51.32 (21.09%), respectively. Based on the results of matrix swelling and drug release, the optimal solutions, target values, and validation experiment results over time were similar and showed consistent patterns with very small biases. The experimental design methodology could be a very promising experimental design method to obtain maximum information with limited time and resources. It could also be very useful in formulation studies by providing a systematic and reliable screening method to characterize significant factors in the sustained release matrix tablet. Copyright © 2011 Elsevier B.V. All rights reserved.

Testing methods of ECR ion source experimental platform

International Nuclear Information System (INIS)

Zhou Changgeng; Hu Yonghong; Li Yan

2006-12-01

The principle and structure of ECR ion source experimental platform were introduce. The testing methods of the parameters of single main component and the comprehensive parameters under the condition of certain beam current and beam spot diameter were summarized in process of manufacturing. Some appropriate testing dates were given. The existent questions (the parameters of plasma density in discharge chamber and accurate hydrogen flow, etc. can not be measured in operation) and resolutions were also put forward. (authors)

Experimental results from a stepped frequency GPR

Directory of Open Access Journals (Sweden)

G. M. Signore

2003-06-01

Full Text Available In the framework of a nationally funded project, a Ground Penetrating Radar (GPR has been developed by the Italian Consortium for Research on Advanced Remote Sensing Systems (CO.RI.S.T.A.. The system was described in a previous paper (Alberti et al., 2002. As new aspects, the system is a stepped frequency GPR that can work both in gated and ungated mode, and the antennas can be moved automatically in a controlled fashion. As aspects of geophysical interest, the system is exploitable in situations wherein a high resolution and a shallow penetration in the soil (a few meters are required. Possibly, this is an example of probing a landscape. This paper completes the results of Alberti et al. (2002, wherein laboratory tests where described, by providing the main results obtained during an outdoor experimental campaign, performed fi rst in a controlled site and then in an archaeological site.

Optimization of instrumental neutron activation analysis method by means of 2k experimental design technique aiming the validation of analytical procedures

International Nuclear Information System (INIS)

Petroni, Robson; Moreira, Edson G.

2013-01-01

In this study optimization of procedures and standardization of Instrumental Neutron Activation Analysis (INAA) methods were carried out for the determination of the elements arsenic, chromium, cobalt, iron, rubidium, scandium, selenium and zinc in biological materials. The aim is to validate the analytical methods for future accreditation at the National Institute of Metrology, Quality and Technology (INMETRO). The 2 k experimental design was applied for evaluation of the individual contribution of selected variables of the analytical procedure in the final mass fraction result. Samples of Mussel Tissue Certified Reference Material and multi-element standards were analyzed considering the following variables: sample decay time, counting time and sample distance to detector. The standard multi-element concentration (comparator standard), mass of the sample and irradiation time were maintained constant in this procedure. By means of the statistical analysis and theoretical and experimental considerations it was determined the optimized experimental conditions for the analytical methods that will be adopted for the validation procedure of INAA methods in the Neutron Activation Analysis Laboratory (LAN) of the Research Reactor Center (CRPq) at the Nuclear and Energy Research Institute (IPEN - CNEN/SP). Optimized conditions were estimated based on the results of z-score tests, main effect and interaction effects. The results obtained with the different experimental configurations were evaluated for accuracy (precision and trueness) for each measurement. (author)

Results of bone regenerate study after osteosynthesis with bioinert and calcium phosphate-coated bioactive implants in experimental femoral neck fractures (experimental study

Directory of Open Access Journals (Sweden)

K. S. Kazanin

2015-01-01

Full Text Available Objective - to analyze the results of X-ray, cytomorphometric and immunohistochemistry experimental studies of bone regenerates after osteosynthesis with bioinert and calcium phosphate-coated bioactive implants. Material and methods. The study was conducted on experimental femoral neck fractures in rabbit males. Reparative osteogenesis processes were studied in groups of bioinert titanium implant osteosynthesis and calcium phosphate-coated bioactive titanium implant osteosynthesis. The animals were clinically followed-up during the postoperative period. X-ray, cytomorphometric and immunohistochemistry studies of samples extracted from femoral bones were conducted over time on days 1, 7, 14, 30 and 60. The animal experiments were kept and treated according to recommendations of international standards, Helsinki Declaration on animal welfare and approved by the local ethics committee. All surgeries were performed under anesthesia, and all efforts were made to minimize the suffering of the animals. Results. In the animal group without femoral neck fracture osteosynthesis, femoral neck pseudoarthrosis was observed at the end of the experiment. The results of cytomorphometric and immunohistochemistry studies conducted on day 60 of the experiment confirmed that the cellular composition of the bone regenerate in the group of calcium phosphate-coated bioactive titanium implants corresponded to a more mature bone tissue than in the group of bioinert titanium implants. Conclusion. The results of the statistical analysis of cytomorphometric and immunohistochemistry data show that the use of calcium phosphate-coated bioactive titanium implants allows to achieve significantly earlier bone tissue regeneration.

Experimental verification on limit load estimation method for pipes with an arbitrary shaped circumferential surface flaw

International Nuclear Information System (INIS)

Li, Yinsheng; Hasegawa, Kunio; Miura, Naoki; Hoshino, Katsuaki

2010-01-01

When a flaw is detected in stainless steel pipes during in-service inspection, the limit load criterion given in the codes such as JSME Rules on Fitness-for-Service for Nuclear Power Plants or ASME Boiler and Pressure Vessel Code Section XI can be applied to evaluate the integrity of the pipe. However, in these codes, the limit load criterion is only provided for pipes containing a flaw with uniform depth, although many flaws with complicated shape such as stress corrosion cracking have been actually detected in pipes. In order to evaluate the integrity of the flawed pipes for general case, a limit load estimation method has been proposed by authors considering a circumferential surface flaw with arbitrary shape. The plastic collapse bending moment and corresponding stress are obtained by dividing the surface flaw into several segmented sub-flaws. In this paper, the proposed method was verified by comparing with experimental results. Four-point bending experiments were carried out for full scale stainless steel pipes with a symmetrical or non-symmetrical circumferential flaw. Estimated failure bending moments by the proposed method were found to be in good agreement with the experimental results, and the proposed method was confirmed to be effective for evaluating bending failure of pipes with flaw. (author)

The IPIRG-1 pipe system fracture tests: Experimental results

International Nuclear Information System (INIS)

Scott, P.; Olson, R.J.; Wilkowski, G.M.

1994-01-01

As part of the First International Piping Integrity Research Group (IPIRG-1) program, six dynamic pipe system experiments were conducted. The objective of these experiments was to generate experimental data to assess analysis methodologies for characterizing the fracture behavior of circumferentially cracked pipe in a representative piping system subjected to combined inertial and displacement-controlled stresses. A unique experimental facility was designed and constructed. The pipe system evaluated was an expansion loop with over 30 m (100 feet) of 16-inch nominal diameter Schedule 100 pipe. The experimental facility was equipped with special hardware to ensure that system boundary conditions could be appropriately modeled. The test matrix involved one uncracked and five cracked dynamic pipe system experiments. The uncracked-pipe experiment was conducted to evaluate the piping system damping and natural frequency characteristics. The cracked-pipe experiments were conducted to evaluate the fracture behavior, piping system response, and fracture stability characteristics of five different materials. All cracked-pipe experiments were conducted at PWR conditions. Material characterization efforts provided the tensile and fracture toughness properties of the different pipe materials at various strain rates and temperatures. Key results from the six pipe system experiments and material characterization efforts are presented. Detailed analyses will be published in a companion paper

Experimental method to predict avalanches based on neural networks

Directory of Open Access Journals (Sweden)

V. V. Zhdanov

2016-01-01

Full Text Available The article presents results of experimental use of currently available statistical methods to classify the avalanche‑dangerous precipitations and snowfalls in the Kishi Almaty river basin. The avalanche service of Kazakhstan uses graphical methods for prediction of avalanches developed by I.V. Kondrashov and E.I. Kolesnikov. The main objective of this work was to develop a modern model that could be used directly at the avalanche stations. Classification of winter precipitations into dangerous snowfalls and non‑dangerous ones was performed by two following ways: the linear discriminant function (canonical analysis and artificial neural networks. Observational data on weather and avalanches in the gorge Kishi Almaty in the gorge Kishi Almaty were used as a training sample. Coefficients for the canonical variables were calculated by the software «Statistica» (Russian version 6.0, and then the necessary formula had been constructed. The accuracy of the above classification was 96%. Simulator by the authors L.N. Yasnitsky and F.М. Cherepanov was used to learn the neural networks. The trained neural network demonstrated 98% accuracy of the classification. Prepared statistical models are recommended to be tested at the snow‑avalanche stations. Results of the tests will be used for estimation of the model quality and its readiness for the operational work. In future, we plan to apply these models for classification of the avalanche danger by the five‑point international scale.

Comparing the effects of community service and imprisonment on reconviction: results from a quasi-experimental Danish study

DEFF Research Database (Denmark)

Klement, Christian

2015-01-01

Objective This study compares reconviction rates for Danish offenders sentenced to community service and imprisonment. A large general sample of offenders (n = 1602) is examined. Methods The study relies on a quasi-experimental design and uses propensity score matching as well as logistic....... Results Imprisonment is associated with a higher rate of recidivism and the result is statistically significant at conventional statistical levels. Conclusions Community service (CS) compared to imprisonment appears to cause a lower reconviction rate in general. Additional research is needed to shed light...

Longitudinal bunch diagnostics using coherent transition radiation spectroscopy. Physical principles, multichannel spectrometer, experimental results, mathematical methods

International Nuclear Information System (INIS)

Schmidt, Bernhard; Wesch, Stephan; Behrens, Christopher; Koevener, Toke; Hass, Eugen; Casalbuoni, Sara

2018-03-01

The generation and properties of transition radiation (TR) are thoroughly treated. The spectral energy density, as described by the Ginzburg-Frank formula, is computed analytically, and the modifications caused by the finite size of the TR screen and by near-field diffraction effects are carefully analyzed. The principles of electron bunch shape reconstruction using coherent transition radiation are outlined. Spectroscopic measurements yield only the magnitude of the longitudinal form factor but not its phase. Two phase retrieval methods are investigated and illustrated with model calculations: analytic phase computation by means of the Kramers-Kronig dispersion relation, and iterative phase retrieval. Particular attention is paid to the ambiguities which are unavoidable in the reconstruction of longitudinal charge density profiles from spectroscopic data. The origin of these ambiguities has been identified and a thorough mathematical analysis is presented. The experimental part of the paper comprises a description of our multichannel infrared and THz spectrometer and a selection of measurements at FLASH, comparing the bunch profiles derived from spectroscopic data with those determined with a transversely deflecting microwave structure. A rigorous derivation of the Kramers-Kronig phase formula is presented in Appendix A. Numerous analytic model calculations can be found in Appendix B. The differences between normal and truncated Gaussians are discussed in Appendix C. Finally, Appendix D contains a short description of the propagation of an electromagnetic wave front by two-dimensional fast Fourier transformation. This is the basis of a powerful numerical Mathematica trademark code THzTransport, which permits the propagation of electromagnetic wave fronts through a beam line consisting of drift spaces, lenses, mirrors and apertures.

Longitudinal bunch diagnostics using coherent transition radiation spectroscopy. Physical principles, multichannel spectrometer, experimental results, mathematical methods

Energy Technology Data Exchange (ETDEWEB)

Schmidt, Bernhard; Wesch, Stephan; Behrens, Christopher [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Koevener, Toke [Hamburg Univ. (Germany); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Hass, Eugen [Hamburg Univ. (Germany); Casalbuoni, Sara [Karlsruhe Institute of Technology (Germany). Inst. for Beam Physics and Technology; Schmueser, Peter [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hamburg Univ. (Germany)

2018-03-15

The generation and properties of transition radiation (TR) are thoroughly treated. The spectral energy density, as described by the Ginzburg-Frank formula, is computed analytically, and the modifications caused by the finite size of the TR screen and by near-field diffraction effects are carefully analyzed. The principles of electron bunch shape reconstruction using coherent transition radiation are outlined. Spectroscopic measurements yield only the magnitude of the longitudinal form factor but not its phase. Two phase retrieval methods are investigated and illustrated with model calculations: analytic phase computation by means of the Kramers-Kronig dispersion relation, and iterative phase retrieval. Particular attention is paid to the ambiguities which are unavoidable in the reconstruction of longitudinal charge density profiles from spectroscopic data. The origin of these ambiguities has been identified and a thorough mathematical analysis is presented. The experimental part of the paper comprises a description of our multichannel infrared and THz spectrometer and a selection of measurements at FLASH, comparing the bunch profiles derived from spectroscopic data with those determined with a transversely deflecting microwave structure. A rigorous derivation of the Kramers-Kronig phase formula is presented in Appendix A. Numerous analytic model calculations can be found in Appendix B. The differences between normal and truncated Gaussians are discussed in Appendix C. Finally, Appendix D contains a short description of the propagation of an electromagnetic wave front by two-dimensional fast Fourier transformation. This is the basis of a powerful numerical Mathematica trademark code THzTransport, which permits the propagation of electromagnetic wave fronts through a beam line consisting of drift spaces, lenses, mirrors and apertures.

Zr-Fe-Sn Ternary System Phase Diagrams- New Experimental Results

International Nuclear Information System (INIS)

Nieva, N; Gomez, A; Arias, D

2004-01-01

New experimental results for the Zr-Fe-Sn ternary system are presented in this paper. The phases present and equilibrium relations for the 900 o C isothermal on the central zone of the Gibbs triangle are analysed. A set of ternary alloys was designed and obtained, and they were analysed by semi quantitative SEM- EDS, XRD, and metallographic samples. The resulting ternary phase diagrams are presented here (JCH)

Numerical models: Detailing and simulation techniques aimed at comparison with experimental data, support to test result interpretation

International Nuclear Information System (INIS)

Lin Chiwen

2001-01-01

This part of the presentation discusses the modelling details required and the simulation techniques available for analyses, facilitating the comparison with the experimental data and providing support for interpretation of the test results. It is organised to cover the following topics: analysis inputs; basic modelling requirements for reactor coolant system; method applicable for reactor cooling system; consideration of damping values and integration time steps; typical analytic models used for analysis of reactor pressure vessel and internals; hydrodynamic mass and fluid damping for the internal analysis; impact elements for fuel analysis; and PEI theorem and its applications. The intention of these topics is to identify the key parameters associated with models of analysis and analytical methods. This should provide proper basis for useful comparison with the test results

Numerical and experimental evaluation of masonry prisms by finite element method

Directory of Open Access Journals (Sweden)

C. F.R. SANTOS

Full Text Available Abstract This work developed experimental tests and numerical models able to represent the mechanical behavior of prisms made of ordinary and high strength concrete blocks. Experimental tests of prisms were performed and a detailed micro-modeling strategy was adopted for numerical analysis. In this modeling technique, each material (block and mortar was represented by its own mechanical properties. The validation of numerical models was based on experimental results. It was found that the obtained numerical values of compressive strength and modulus of elasticity differ by 5% from the experimentally observed values. Moreover, mechanisms responsible for the rupture of the prisms were evaluated and compared to the behaviors observed in the tests and those described in the literature. Through experimental results it is possible to conclude that the numerical models have been able to represent both the mechanical properties and the mechanisms responsible for failure.

Study of a vibrating plate: comparison between experimental (ESPI) and analytical results

Science.gov (United States)

Romero, G.; Alvarez, L.; Alanís, E.; Nallim, L.; Grossi, R.

2003-07-01

Real-time electronic speckle pattern interferometry (ESPI) was used for tuning and visualization of natural frequencies of a trapezoidal plate. The plate was excited to resonant vibration by a sinusoidal acoustical source, which provided a continuous range of audio frequencies. Fringe patterns produced during the time-average recording of the vibrating plate—corresponding to several resonant frequencies—were registered. From these interferograms, calculations of vibrational amplitudes by means of zero-order Bessel functions were performed in some particular cases. The system was also studied analytically. The analytical approach developed is based on the Rayleigh-Ritz method and on the use of non-orthogonal right triangular co-ordinates. The deflection of the plate is approximated by a set of beam characteristic orthogonal polynomials generated by using the Gram-Schmidt procedure. A high degree of correlation between computational analysis and experimental results was observed.

Experimental determination of the heat transfer coefficient in shell-and-tube condensers using the Wilson plot method

Directory of Open Access Journals (Sweden)

Havlik Jan

2017-01-01

Full Text Available This article deals with the experimental determination of heat transfer coefficients. The calculation of heat transfer coefficients constitutes a crucial issue in design and sizing of heat exchangers. The Wilson plot method and its modifications based on measured experimental data utilization provide an appropriate tool for the analysis of convection heat transfer processes and the determination of convection coefficients in complex cases. A modification of the Wilson plot method for shell-and-tube condensers is proposed. The original Wilson plot method considers a constant value of thermal resistance on the condensation side. The heat transfer coefficient on the cooling side is determined based on the change in thermal resistance for different conditions (fluid velocity and temperature. The modification is based on the validation of the Nusselt theory for calculating the heat transfer coefficient on the condensation side. A change of thermal resistance on the condensation side is expected and the value is part of the calculation. It is possible to improve the determination accuracy of the criterion equation for calculation of the heat transfer coefficient using the proposed modification. The criterion equation proposed by this modification for the tested shell-and-tube condenser achieves good agreement with the experimental results and also with commonly used theoretical methods.

Electrical and thermal behavior of unsaturated soils: experimental results

Science.gov (United States)

Nouveau, Marie; Grandjean, Gilles; Leroy, Philippe; Philippe, Mickael; Hedri, Estelle; Boukcim, Hassan

2016-05-01

When soil is affected by a heat source, some of its properties are modified, and in particular, the electrical resistivity due to changes in water content. As a result, these changes affect the thermal properties of soil, i.e., its thermal conductivity and diffusivity. We experimentally examine the changes in electrical resistivity and thermal conductivity for four soils with different grain size distributions and clay content over a wide range of temperatures, from 20 to 100 °C. This temperature range corresponds to the thermal conditions in the vicinity of a buried high voltage cable or a geothermal system. Experiments were conducted at the field scale, at a geothermal test facility, and in the laboratory using geophysical devices and probing systems. The results show that the electrical resistivity decreases and the thermal conductivity increases with temperature up to a critical temperature depending on soil types. At this critical temperature, the air volume in the pore space increases with temperature, and the resulting electrical resistivity also increases. For higher temperatures , the thermal conductivity increases sharply with temperature up to a second temperature limit. Beyond it, the thermal conductivity drops drastically. This limit corresponds to the temperature at which most of the water evaporates from the soil pore space. Once the evaporation is completed, the thermal conductivity stabilizes. To explain these experimental results, we modeled the electrical resistivity variations with temperature and water content in the temperature range 20 - 100°C, showing that two critical temperatures influence the main processes occurring during heating at temperatures below 100 °C.

Experimentally aided development of a turbine heat transfer prediction method

International Nuclear Information System (INIS)

Forest, A.E.; White, A.J.; Lai, C.C.; Guo, S.M.; Oldfield, M.L.G.; Lock, G.D.

2004-01-01

In the design of cooled turbomachinery blading a central role is played by the computer methods used to optimise the aerodynamic and thermal performance of the turbine aerofoils. Estimates of the heat load on the turbine blading should be as accurate as possible, in order that adequate life may be obtained with the minimum cooling air requirement. Computer methods are required which are able to model transonic flows, which are a mixture of high temperature combustion gases and relatively cool air injected through holes in the aerofoil surface. These holes may be of complex geometry, devised after empirical studies of the optimum shape and the most cost effective manufacturing technology. The method used here is a further development of the heat transfer design code (HTDC), originally written by Rolls-Royce plc under subcontract to Rolls-Royce Inc for the United States Air Force. The physical principles of the modelling employed in the code are explained without extensive mathematical details. The paper describes the calibration of the code in conjunction with a series of experimental measurements on a scale model of a high-pressure nozzle guide vane at non-dimensionally correct engine conditions. The results are encouraging, although indicating that some further work is required in modelling highly accelerated pressure surface flow

Advanced Supersonic Nozzle Concepts: Experimental Flow Visualization Results Paired With LES

Science.gov (United States)

Berry, Matthew; Magstadt, Andrew; Stack, Cory; Gaitonde, Datta; Glauser, Mark; Syracuse University Team; The Ohio State University Team

2015-11-01

Advanced supersonic nozzle concepts are currently under investigation, utilizing multiple bypass streams and airframe integration to bolster performance and efficiency. This work focuses on the parametric study of a supersonic, multi-stream jet with aft deck. The single plane of symmetry, rectangular nozzle, displays very complex and unique flow characteristics. Flow visualization techniques in the form of PIV and schlieren capture flow features at various deck lengths and Mach numbers. LES is compared to the experimental results to both validate the computational model and identify limitations of the simulation. By comparing experimental results to LES, this study will help create a foundation of knowledge for advanced nozzle designs in future aircraft. SBIR Phase II with Spectral Energies, LLC under direction of Barry Kiel.

Experimental results pertaining to the performance of thermal igniters

International Nuclear Information System (INIS)

Carmel, M.K.

1989-10-01

This report summarizes the results of various experimental programs regarding the performance of thermal igniters for the deliberate ignition of hydrogen in light water reactors. Experiments involving both premixed combustion and combustion with continuous hydrogen injection are reviewed. Combustion characteristics examined include flammability limits of hydrogen:air and hydrogen:air:steam mixtures, combustion pressure rises, combustion completeness, flame speeds, and heat transfer aspects. Comparisons of igniter type and igniter reliability under simulated reactor accident conditions are included. The results of the research programs provide a broad data base covering nearly all aspects of hydrogen combustion related to the performance of deliberate ignition systems

Optimization of instrumental neutron activation analysis method by means of 2{sup k} experimental design technique aiming the validation of analytical procedures

Energy Technology Data Exchange (ETDEWEB)

Petroni, Robson; Moreira, Edson G., E-mail: rpetroni@ipen.br, E-mail: emoreira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

In this study optimization of procedures and standardization of Instrumental Neutron Activation Analysis (INAA) methods were carried out for the determination of the elements arsenic, chromium, cobalt, iron, rubidium, scandium, selenium and zinc in biological materials. The aim is to validate the analytical methods for future accreditation at the National Institute of Metrology, Quality and Technology (INMETRO). The 2{sup k} experimental design was applied for evaluation of the individual contribution of selected variables of the analytical procedure in the final mass fraction result. Samples of Mussel Tissue Certified Reference Material and multi-element standards were analyzed considering the following variables: sample decay time, counting time and sample distance to detector. The standard multi-element concentration (comparator standard), mass of the sample and irradiation time were maintained constant in this procedure. By means of the statistical analysis and theoretical and experimental considerations it was determined the optimized experimental conditions for the analytical methods that will be adopted for the validation procedure of INAA methods in the Neutron Activation Analysis Laboratory (LAN) of the Research Reactor Center (CRPq) at the Nuclear and Energy Research Institute (IPEN - CNEN/SP). Optimized conditions were estimated based on the results of z-score tests, main effect and interaction effects. The results obtained with the different experimental configurations were evaluated for accuracy (precision and trueness) for each measurement. (author)

Recent experimental results on Coherent Pion production in neutrino interactions

Energy Technology Data Exchange (ETDEWEB)

Camilleri, L. [Columbia University, Nevis Labs Irvington on Hudson, New York 10533 (United States)

2012-08-15

Recent experimental results on charged current ({pi}{sup +}) coherent production by KEK and SciBooNE and neutral current ({pi}{sup 0}) production by MiniBooNE, SciBooNE and NOMAD will be discussed. The NOMAD results are at an average neutrino energy of 25 GeV whereas the energies of the other experiments are in an average energy range of 1-2 GeV. A comparison with some theoretical models will be presented.

An experimental design method leading to chemical Turing patterns.

Science.gov (United States)

Horváth, Judit; Szalai, István; De Kepper, Patrick

2009-05-08

Chemical reaction-diffusion patterns often serve as prototypes for pattern formation in living systems, but only two isothermal single-phase reaction systems have produced sustained stationary reaction-diffusion patterns so far. We designed an experimental method to search for additional systems on the basis of three steps: (i) generate spatial bistability by operating autoactivated reactions in open spatial reactors; (ii) use an independent negative-feedback species to produce spatiotemporal oscillations; and (iii) induce a space-scale separation of the activatory and inhibitory processes with a low-mobility complexing agent. We successfully applied this method to a hydrogen-ion autoactivated reaction, the thiourea-iodate-sulfite (TuIS) reaction, and noticeably produced stationary hexagonal arrays of spots and parallel stripes of pH patterns attributed to a Turing bifurcation. This method could be extended to biochemical reactions.

Experimental method and preliminary studies of the passive containment water film evaporation mass transfer

Energy Technology Data Exchange (ETDEWEB)

Li, Cheng [State Nuclear Power Technology Research, Beijing (China). Development Center; State Nuclear Power Research Institute, Beijing (China); Yang, Lin; Zhao, Wei; Zhou, Shan; Du, Wangfang; Gao, Zhan; Li, Honegsen [State Nuclear Power Technology Research, Beijing (China). Development Center

2017-05-15

For larger containments and higher operation parameters, characteristics of the outside cooling of the PCCS are very important for the analysis on the containment integrity. A preliminary analysis was made and a four-step experimental method was used to numerically analyze the falling water film evaporation for the advanced passive containment. Then, the water flow stability along the outside wall of the containment was studied. The results fit well with those correlations without airflow when the air velocity is less than 5.0 m/s. However, when the air velocity is larger than 5.0 m/s, the influence of the air velocity on the water film will appear and the mean water film thickness will be thicker. Based on the prototype operation parameters, experimental studies were carried and the results were compared with the Dittus-Boelter correlation within the operation ranges. A modification factor was proposed for the conservative application of this correlation for nuclear safety analysis.

A novel approach to the experimental study on methane/steam reforming kinetics using the Orthogonal Least Squares method

Science.gov (United States)

Sciazko, Anna; Komatsu, Yosuke; Brus, Grzegorz; Kimijima, Shinji; Szmyd, Janusz S.

2014-09-01

For a mathematical model based on the result of physical measurements, it becomes possible to determine their influence on the final solution and its accuracy. However, in classical approaches, the influence of different model simplifications on the reliability of the obtained results are usually not comprehensively discussed. This paper presents a novel approach to the study of methane/steam reforming kinetics based on an advanced methodology called the Orthogonal Least Squares method. The kinetics of the reforming process published earlier are divergent among themselves. To obtain the most probable values of kinetic parameters and enable direct and objective model verification, an appropriate calculation procedure needs to be proposed. The applied Generalized Least Squares (GLS) method includes all the experimental results into the mathematical model which becomes internally contradicted, as the number of equations is greater than number of unknown variables. The GLS method is adopted to select the most probable values of results and simultaneously determine the uncertainty coupled with all the variables in the system. In this paper, the evaluation of the reaction rate after the pre-determination of the reaction rate, which was made by preliminary calculation based on the obtained experimental results over a Nickel/Yttria-stabilized Zirconia catalyst, was performed.

Structural Analysis of InxGa1−xN/GaN MQWs by Different Experimental Methods

International Nuclear Information System (INIS)

Ding Bin-Beng; Pan Feng; Fa Tao; Cheng Feng-Feng; Yao Shu-De; Feng Zhe-Chuan

2011-01-01

Structural properties of In x Ga 1−x N/GaN multi-quantum wells (MQWs) grown on sapphire by metal organic chemical vapor deposition are investigated by synchrotron radiation x-ray diffraction (SRXRD), Rutherford backscattering/channelling (RBS/C) and high-resolution transmission electron microscopy. The sample consists of eight periods of In x Ga 1−x N/GaN wells of 2.1 nm thickness and 8.5 nm thickness of GaN barrier, and the results are very close, which verifies the accuracy of the three methods. The indium content in In x Ga 1−x N/GaN MQWs by SRXRD and RBS/C is estimated, and results are in general the same. By RBS/C random spectra, the indium atomic lattice substitution rate is 94.0%, indicating that almost all indium atoms in In x Ga 1−x N/GaN MQWs are at substitution, that the indium distribution of each layer in In x Ga 1−x N/GaN MQWs is very homogeneous and that the In x Ga 1−x N/GaN MQWs have a very good crystalline quality. It is not accurate to estimate indium content in In x Ga 1−x N/GaN MQWs by photoluminescence (PL) spectra, because the result from the PL experimental method is very different from the results by the SRXRD and RBS/C experimental methods. (cross-disciplinary physics and related areas of science and technology)

Verification of experimental dynamic strength methods with atomistic ramp-release simulations

Science.gov (United States)

Moore, Alexander P.; Brown, Justin L.; Lim, Hojun; Lane, J. Matthew D.

2018-05-01

Material strength and moduli can be determined from dynamic high-pressure ramp-release experiments using an indirect method of Lagrangian wave profile analysis of surface velocities. This method, termed self-consistent Lagrangian analysis (SCLA), has been difficult to calibrate and corroborate with other experimental methods. Using nonequilibrium molecular dynamics, we validate the SCLA technique by demonstrating that it accurately predicts the same bulk modulus, shear modulus, and strength as those calculated from the full stress tensor data, especially where strain rate induced relaxation effects and wave attenuation are small. We show here that introducing a hold in the loading profile at peak pressure gives improved accuracy in the shear moduli and relaxation-adjusted strength by reducing the effect of wave attenuation. When rate-dependent effects coupled with wave attenuation are large, we find that Lagrangian analysis overpredicts the maximum unload wavespeed, leading to increased error in the measured dynamic shear modulus. These simulations provide insight into the definition of dynamic strength, as well as a plausible explanation for experimental disagreement in reported dynamic strength values.

Experimental validation of the buildings energy performance (PEC assessment methods with reference to occupied spaces heating

Directory of Open Access Journals (Sweden)

Cristian PETCU

2010-01-01

provided by measurements and to those provided by the monthly calculation (NP 048-2006. The deviations of 1.45% and 2.2% respectively validate the hourly calculation model, as they actually have no physical significance. The report presents a phenomenological analysis of the building transfer functions synthesized as tev (τ, functions which attest their phenomenological objectivity in macro and hourly terms. The case studies completing the calculation models experimental validation emphasize unacceptably large differences between the results provided by the use of standardized calculation methods (Mc 001 / 2-2006 and SR EN 13790:2009 and those specific to the methods referred to in this report, experimentally validated.

Determination of processing-induced stresses and properties of layered and graded coatings: Experimental method and results for plasma-sprayed Ni-Al{sub 2}O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Kesler, O.; Finot, M.; Suresh, S. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials Science and Engineering; Sampath, S. [State Univ. of New York, Stony Brook, NY (United States). Dept. of Materials Science and Engineering

1997-08-01

An experimental method is proposed which enables the determination of processing-induced intrinsic stresses, elastic modulus, and coefficients of thermal expansion of surface coatings of homogeneous and graded compositions. In this method, a number of identical substrate specimens are coated simultaneously with surface layers of fixed or graded compositions, and specimens with different layer thicknesses are periodically removed from the deposition chamber. It is shown that the following results can be obtained from a knowledge of the strain or curvature and thermal history of the coated specimens, in conjunction with simple four-point bend tests and thermal loading/cycling at different temperatures: (i) the magnitude of the processing-induced intrinsic stresses through the thickness of the coating, (ii) the in-plane Young`s modulus, E, as a function of the coating thickness, (iii) the coefficient of thermal expansion, {alpha}, as a function of the coating thickness, (iv) the variation of E and {alpha} as a function of temperature at any thickness location within the coating, and (v) the separation of internal stresses arising from thermal expansion mismatch between different constituent phases or layers from those arising from the deposition process (so-called intrinsic or quench stresses). The thermomechanical analyses underlying this method are discussed in detail, and its significance and limitations are addressed. The proposed method is used to determine the evolution of processing-induced stresses during the successive build-up of plasma-sprayed Ni-Al{sub 2}O{sub 3} coatings of homogeneous and graded compositions.

The Trojan Horse method for nuclear astrophysics: Recent results for direct reactions

International Nuclear Information System (INIS)

Tumino, A.; Gulino, M.; Spitaleri, C.; Cherubini, S.; Romano, S.; Cognata, M. La; Pizzone, R. G.; Rapisarda, G. G.; Lamia, L.

2014-01-01

The Trojan Horse method is a powerful indirect technique to determine the astrophysical factor for binary rearrangement processes A+x→b+B at astrophysical energies by measuring the cross section for the Trojan Horse (TH) reaction A+a→B+b+s in quasi free kinematics. The Trojan Horse Method has been successfully applied to many reactions of astrophysical interest, both direct and resonant. In this paper, we will focus on direct sub-processes. The theory of the THM for direct binary reactions will be shortly presented based on a few-body approach that takes into account the off-energy-shell effects and initial and final state interactions. Examples of recent results will be presented to demonstrate how THM works experimentally

The Trojan Horse method for nuclear astrophysics: Recent results for direct reactions

Energy Technology Data Exchange (ETDEWEB)

Tumino, A.; Gulino, M. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy and Università degli Studi di Enna Kore, Enna (Italy); Spitaleri, C.; Cherubini, S.; Romano, S. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy and Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy); Cognata, M. La; Pizzone, R. G.; Rapisarda, G. G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Lamia, L. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy)

2014-05-09

The Trojan Horse method is a powerful indirect technique to determine the astrophysical factor for binary rearrangement processes A+x→b+B at astrophysical energies by measuring the cross section for the Trojan Horse (TH) reaction A+a→B+b+s in quasi free kinematics. The Trojan Horse Method has been successfully applied to many reactions of astrophysical interest, both direct and resonant. In this paper, we will focus on direct sub-processes. The theory of the THM for direct binary reactions will be shortly presented based on a few-body approach that takes into account the off-energy-shell effects and initial and final state interactions. Examples of recent results will be presented to demonstrate how THM works experimentally.

Liquid blanket MHD effects experimental results from LMEL facility at SWIP

International Nuclear Information System (INIS)

Xu Zengyu; Pan Chuanjie; Liu Yong; Pan Chuanhong; Reed, C.B.

2007-01-01

The self-cooled /helium-cooled liquid metal blanket concept is an attractive ITER and DEMO blanket candidate as it has low operating pressure, simplicity, and a convenient tritium breeding cycle. But MHD pressure drop remains a key issue, especially in ducts with flow channel inserts (FCI), where the reduction in MHD pressure drop is difficult to predict with existing tools, and there are no available experimental data to check current predictions. To understand well various kinds of MHD effects, it is important for us to analyze and understand FCI effects. In this paper, we present measurements of the MHD effects due to off normal power shutdown, two-dimensional effects due to channel velocity profiles, three-dimensional effects caused by manifolds, and surface/bulk instability effects as a result of insulator coating imperfections. These results were collected from the Liquid Metal Experimental Loop (LMEL) facility at Southwestern Institute of Physics, China and in collaboration with Argonne National Laboratory, US under an umbrella of the People's Republic of China/United States program of cooperation in magnetic fusion. Some results were observed for the first time, such as two dimensional effects and instabilities due to insulator coating imperfections. The experiments were conducted under the following conditions: a uniform magnetic field volume of 80 x 170 x 740 mm and a maximum value of magnetic field, B 0 , of 2 Tesla. The mean flow velocity v 0 was measured with an electromagnetic (EM) flow meter (error of 1.2%); a Liquid-metal Electro-magnetic Velocity Instrument (LEVI) was provided by Argonne National Laboratory. The flow was driven by two Electro-magnetic (EM) pumps (6.5+11.6 m3/h); the operating temperature was 85 centigrade degree due to self-heating by the EM pump and friction of the fluid against the loop piping. Experimental parameters were: Hartmann number, M, up to 3500, velocity v 0 up to 1.2 m/s under magnetic field, and B 0 =1.95 Tesla

Pathogenesis of acute radiation effects in the urinary bladder. Experimental results

International Nuclear Information System (INIS)

Doerr, W.; Eckhardt, M.; Ehme, A.; Koi, S.

1998-01-01

Purpose: The present review summarizes experimental studies of the pathogenesis of acute radiation-induced changes in urinary bladder function. Material and methods: Transurethral cystometry was used for longitudinal assessment of bladder function in mice. With this technique, radiation-induced changes in storage capacity can be quantified. In histological studies, changes in urothelial cell density and in urothelial protein expression during the acute radiation response were determined. Acetylsalicylic acid (ASA) was used for the treatment of acute functional changes. Results: The histological studies did not reveal any systematic fluctuations in urothelial cell density during the time of the acute radiation response. However, characteristic changes in the expression of proteins associated with urothelial cell function, differentiation and cell contact were observed, which correlated with the functional impairment. By local or systemical application of ASA, a significant restoration of bladder function compared to placebo treatment could be achieved. Conclusion: Acute functional radiation effects in the urinary bladder are not based on urothelial denudation. However, changes in protein expression indicate an impairment of the urothelial barrier function. The results of ASA treatment demonstrate that prostaglandins are involved in the response. Alterations in urothelial or endothelial prostaglandin metabolism may be primarily radiation-induced or secondary because of the impaired urothelial barrier. (orig.) [de

The Ramsey method in high-precision mass spectrometry with Penning traps Experimental results

CERN Document Server

George, S; Herfurth, F; Herlert, A; Kretzschmar, M; Nagy, S; Schwarz, S; Schweikhard, L; Yazidjian, C

2007-01-01

The highest precision in direct mass measurements is obtained with Penning trap mass spectrometry. Most experiments use the interconversion of the magnetron and cyclotron motional modes of the stored ion due to excitation by external radiofrequency-quadrupole fields. In this work a new excitation scheme, Ramsey's method of time-separated oscillatory fields, has been successfully tested. It has been shown to reduce significantly the uncertainty in the determination of the cyclotron frequency and thus of the ion mass of interest. The theoretical description of the ion motion excited with Ramsey's method in a Penning trap and subsequently the calculation of the resonance line shapes for different excitation times, pulse structures, and detunings of the quadrupole field has been carried out in a quantum mechanical framework and is discussed in detail in the preceding article in this journal by M. Kretzschmar. Here, the new excitation technique has been applied with the ISOLTRAP mass spectrometer at ISOLDE/CERN fo...

Incremental elongation or ratchetting - Experimental tests and practical method of analysis (on stainless steel 304L and 306L)

International Nuclear Information System (INIS)

Cousseran, Pierre; Lebey, Jacques; Roche, Roland; Clement, Gerard; Moulin, Didier.

1980-12-01

Ratchetting, or incremental elongation can be considered as a creep enhancement when cyclic deformations are added to a primary constant load. Under examination, it appears that theoretical models proposed till now do not fit correctly the actual behavior of materials. From experimental tests results performed in Saclay, a simplified method for prevention of ratcheting is proposed. A validation was made by using experimental data from various sources [fr

Recent experimental results on level densities for compound reaction calculations

International Nuclear Information System (INIS)

Voinov, A.V.

2012-01-01

There is a problem related to the choice of the level density input for Hauser-Feshbach model calculations. Modern computer codes have several options to choose from but it is not clear which of them has to be used in some particular cases. Availability of many options helps to describe existing experimental data but it creates problems when it comes to predictions. Traditionally, different level density systematics are based on experimental data from neutron resonance spacing which are available for a limited spin interval and one parity only. On the other hand reaction cross section calculations use the total level density. This can create large uncertainties when converting the neutron resonance spacing to the total level density that results in sizable uncertainties in cross section calculations. It is clear now that total level densities need to be studied experimentally in a systematic manner. Such information can be obtained only from spectra of compound nuclear reactions. The question is does level densities obtained from compound nuclear reactions keep the same regularities as level densities obtained from neutron resonances- Are they consistent- We measured level densities of 59-64 Ni isotopes from proton evaporation spectra of 6,7 Li induced reactions. Experimental data are presented. Conclusions of how level density depends on the neutron number and on the degree of proximity to the closed shell ( 56 Ni) are drawn. The level density parameters have been compared with parameters obtained from the analysis of neutron resonances and from model predictions

Closed Loop Two-Phase Thermosyphon of Small Dimensions: a Review of the Experimental Results

Science.gov (United States)

Franco, Alessandro; Filippeschi, Sauro

2012-06-01

A bibliographical review on the heat and mass transfer in gravity assisted Closed Loop Two Phase Thermosyphons (CLTPT) with channels having a hydraulic diameter of the order of some millimetres and input power below 1 kW is proposed. The available experimental works in the literature are critically analysed in order to highlight the main results and the correlation between mass flow rate and heat input in natural circulation loops. A comparison of different experimental apparatuses and results is made. It is observed that the results are very different among them and in many cases the experimental data disagree with the conventional theory developed for an imposed flow rate. The paper analyses the main differences among the experimental devices and try to understand these disagreements. From the present analysis it is evident that further systematic studies are required to generate a meaningful body of knowledge of the heat and mass transport mechanism in these devices for practical applications in cooling devices or energy systems.

Experimental results for TiO2 melting and release using cold crucible melting

International Nuclear Information System (INIS)

Hong, S. W.; Min, B. T.; Park, I. G.; Kim, H. D.

2000-01-01

To simulate the severe accident phenomena using the real reactor material which melting point is about 2,800K, the melting and release method for materials with high melting point should be developed. This paper discusses the test results for TiO 2 materials using the cold crucible melting method to study the melting and release method of actual corium. To melt and release of few kg of TiO2, the experimental facility is manufactured through proper selection of design parameters such as frequency and capacity of R.F generator, crucible size and capacity of coolant. The melting and release of TiO 2 has been successfully performed in the cold crucible of 15cm in inner diameter and 30cm in height with 30kW RF power generator of 370 KHz. In the melt delivery experiment, about 2.6kg of molten TiO2, 60% of initial charged mass, is released. Rest of it is remained in the watercage in form of the rubble crust formed at the top of crucible and melt crust formed at the interface between the water-cage and melt. Especially, in the melt release test, the location of the working coil is important to make the thin crust at the bottom of the crucible

Experimental and numerical results of a high frequency rotating active magnetic refrigerator

DEFF Research Database (Denmark)

Lozano, Jaime; Engelbrecht, Kurt; Bahl, Christian

2012-01-01

Experimental results for a recently developed prototype magnetic refrigeration device at The Technical University of Denmark (DTU) were obtained and compared with numerical simulation results. A continuously rotating active magnetic regenerator (AMR) using 2.8 kg packed sphere regenerators...

Experimental and numerical results of a high frequency rotating active magnetic refrigerator

DEFF Research Database (Denmark)

Lozano, Jaime; Engelbrecht, Kurt; Bahl, Christian R.H.

2014-01-01

Experimental results for a recently developed prototype magnetic refrigeration device at the Technical University of Denmark (DTU) were obtained and compared with numerical simulation results. A continuously rotating active magnetic regenerator (AMR) using 2.8 kg packed sphere regenerators...

Vertical Instability in EAST: Comparison of Model Predictions with Experimental Results

International Nuclear Information System (INIS)

Qian Jinping; Wan Baonian; Shen Biao; Xiao Bingjia; Sun Youwen; Shi Yuejiang; Lin Shiyao; Li Jiangang; Gong Xianzu

2008-01-01

Growth rates of the axisymmetric mode in elongated plasmas in the experimental advanced superconducting tokamak (EAST) are measured with zero feedback gains and then compared with numerically calculated growth rates for the reconstructed shapes. The comparison is made after loss of vertical position control. The open-loop growth rates were scanned with the number of vessel eigenmodes, which up to 20 is enough to make the growth rates settled. The agreement between the growth rates measured experimentally and the growth rates determined numerically is good. The results show that a linear RZIP model is essentially good enough for the vertical position feedback control.

Methods and experimental techniques in computer engineering

CERN Document Server

Schiaffonati, Viola

2014-01-01

Computing and science reveal a synergic relationship. On the one hand, it is widely evident that computing plays an important role in the scientific endeavor. On the other hand, the role of scientific method in computing is getting increasingly important, especially in providing ways to experimentally evaluate the properties of complex computing systems. This book critically presents these issues from a unitary conceptual and methodological perspective by addressing specific case studies at the intersection between computing and science. The book originates from, and collects the experience of, a course for PhD students in Information Engineering held at the Politecnico di Milano. Following the structure of the course, the book features contributions from some researchers who are working at the intersection between computing and science.

Optical bandgap of semiconductor nanostructures: Methods for experimental data analysis

Science.gov (United States)

Raciti, R.; Bahariqushchi, R.; Summonte, C.; Aydinli, A.; Terrasi, A.; Mirabella, S.

2017-06-01

Determination of the optical bandgap (Eg) in semiconductor nanostructures is a key issue in understanding the extent of quantum confinement effects (QCE) on electronic properties and it usually involves some analytical approximation in experimental data reduction and modeling of the light absorption processes. Here, we compare some of the analytical procedures frequently used to evaluate the optical bandgap from reflectance (R) and transmittance (T) spectra. Ge quantum wells and quantum dots embedded in SiO2 were produced by plasma enhanced chemical vapor deposition, and light absorption was characterized by UV-Vis/NIR spectrophotometry. R&T elaboration to extract the absorption spectra was conducted by two approximated methods (single or double pass approximation, single pass analysis, and double pass analysis, respectively) followed by Eg evaluation through linear fit of Tauc or Cody plots. Direct fitting of R&T spectra through a Tauc-Lorentz oscillator model is used as comparison. Methods and data are discussed also in terms of the light absorption process in the presence of QCE. The reported data show that, despite the approximation, the DPA approach joined with Tauc plot gives reliable results, with clear advantages in terms of computational efforts and understanding of QCE.

Experimental methods of investigation of kinetics and dynamics of nuclear reactors

International Nuclear Information System (INIS)

Costa Oliveira, Jaime M.

1969-03-01

The author presents experimental methods used to study kinetic and dynamic properties of nuclear reactors. Kinetic methods aim at determining characteristic parameters of the behaviour in time of neutrons. Dynamic methods aim at establishing the relationships between the reactor behaviour and its internal and external causes (notably the measurement of transfer functions). The author proposes a classification with respect to the excitation type: periodic excitation (reactivity sinusoidal modulation, source sinusoidal modulation, periodic pulse excitation), non periodic excitation (reactivity monitoring, reactivity linear variation, reactivity variation according to any given law, removal of starting source), random excitation (random reactivity or source excitation), natural fluctuations (alpha-Rossi method, methods of reduced variance, probabilistic methods, correlation methods, spectral analysis method). He also addresses space and energy effects. Applications are reported for low power and power reactors

Methods and experimental coefficients used in the computation of reactor shielding; Methodes et coefficients experimentaux pour le calcul des protections de reacteurs

Energy Technology Data Exchange (ETDEWEB)

Bourgeois, J; Lafore, P; Millot, J P; Rastoin, J; Vathaire, F de [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

1) The concept of an effective removal cross section has been developed in order more easily to compute reactor shielding thicknesses. We have built an experimental facility for the purpose of measuring effective removal cross sections, the value of which had not been published at that time. The first part of this paper describes the device or facility used, the computation method applied, and the results obtained. 2) Starting from this concept, we endeavoured to define a removal cross section as a function of energy. This enabled us to use the method for computations bearing on the attenuation of fast neutrons of any spectrum. An experimental verification was carried out for the case of fission neutrons filtered by a substantial thickness of graphite. 3) Finally, we outline a computation method enabling us to determine the sources of captured gamma rays by the age theory and we give an example of the application in a composite shield. (author) [French] 1) La notion de section efficace effective de deplacement a ete introduite pour calculer commodement les epaisseurs de protection des reacteurs. Nous avons construit un dispositif experimental destine a mesurer les sections efficaces effectives de deplacement dont la valeur n'avait pas ete publiee a cette epoque. La premiere partie de cette communication decrit le dispositif utilise, la methode de calcul employee et les resultats obtenus. 2) A partir de cette notion, nous avons essaye de definir une section efficace de deplacement fonction de l'energie. Ceci permet d'utiliser la methode du deplacement pour des calculs d'attenuation de neutrons rapides dont le spectre est quelconque. Une verification experimentale a ete faite dans le cas de neutrons de fission filtres par une epaisseur notable de graphite. 3) Enfin une methode de calcul permettant de determiner les sources de gamma de capture par la theorie de l'age est exposee et un exemple d'application donne dans une protection composite. (auteur)

LEARNING TO READ SCIENTIFIC RUSSIAN BY THE THREE QUESTION EXPERIMENTAL (3QX) METHOD.

Science.gov (United States)

ALFORD, M.H.T.

A NEW METHOD FOR LEARNING TO READ TECHNICAL LITERATURE IN A FOREIGN LANGUAGE IS BEING DEVELOPED AND TESTED AT THE LANGUAGE CENTRE OF THE UNIVERSITY OF ESSEX, COLCHESTER, ENGLAND. THE METHOD IS CALLED "THREE QUESTION EXPERIMENTAL METHOD (3QX)," AND IT HAS BEEN USED IN THREE COURSES FOR TEACHING SCIENTIFIC RUSSIAN TO PHYSICISTS. THE THREE…

Experimental results of the ATF in-line injection system

International Nuclear Information System (INIS)

Wang, X.J.; Srinivasan-Rao, T.; Batchelor, K.

1995-01-01

The initial experimental results of the Brookhaven accelerator test facility (ATF) in-line injector is presented. The ATF in-line injector employed a full copper RF gun with a pair of solenoid magnets for emittance compensation. The maximum acceleration field of the RF gun was measured to be 130 MV/m. The electron yield from the copper cathode was maximized using p- polarized laser and the Schottky effect. The quantum efficiency under optimum conditions was measured to be 0.04%. The measured electron bunch length was less than 11 ps, which agreed with the laser pulse length measurement using a streak camera. The normalized rms. emittance for 0.25 nC charge is 0.9 ± 0.1 mm-mrad, which is almost four times smaller than the emittance predicted by the space-charge effect for a non-emittance compensation photocathode RF gun. The normalized rms for 0.6 nC charge was measured range from 1 to 3 mm-mrad. This measurement was first experimental demonstration of emittance compensation in a high-gradient, S-band photocathode RF gun

High energy nucleus-nucleus collisions at CERN: Signatures, physical observables and experimental results

International Nuclear Information System (INIS)

Harris, J.W.

1988-02-01

Experimental results on high energy nucleus-nucleus collisions have become available with the recent experiments at CERN utilizing 200 GeV/n oxygen and sulfur beams. Physics motivations for these experiments are presented: a description of predicted signatures for possible formation of a quark-gluon plasma and physical observables that are expected to provide important information for understanding the dynamics of these collisions. A presentation will be made of some of the first experimental results to emerge from this new field. 28 refs., 9 figs

Dynamic Coefficients of a Tilting Pad With Active Lubrication: Comparison Between Theoretical and Experimental Results

DEFF Research Database (Denmark)

Cerda Varela, Alejandro Javier; Santos, Ilmar

2015-01-01

experimental results from the literature for industrial grade passive tilting pad bearings. This initial validation is followed by a comparison with experimental identification results obtained from a test rig featuring the active bearing design. Good overall agreement is observed in both configurations...

Some results of experimental investigation of super-deep penetration into the metal's targets

International Nuclear Information System (INIS)

Andilevko, S.K.; Roman, O.V.; Usherenko, S.M.; Shilkin, V.A.

1994-01-01

The phenomenon of Super-Deep Penetration (SDP) is briefly presented. Various experimental techniques, including that based on neutron-activated autoradiography (NAAR), for experimentally investigating this phenomenon are described. Results from a number of investigations in which the effect on SDP of initial target temperature, the dependence of the concentration on depth for different powder particles and the use of bimetallic targets, are reviewed. The complicated nature of the SDP process and the need for a wider range of experimental data if it is to be fully understood are discussed. (orig.)

F.E. analysis of seismic isolators: comparison with experimental results

International Nuclear Information System (INIS)

Fuller, K.N.G.; Gough, J.; Ahmadi, H.R.

1998-01-01

Analysis of seismic isolators is performed by the ABAQUS code. The force deformation behaviour of a circular layer of rubber bonded to rigid surface was investigated. This model is chosen because of its simplicity and the relatively short processing time required. A 3-dimensional model was used for finite element calculations. Comparison of calculated values with experimental results is shown

Adsorption of methanol molecule on graphene: Experimental results and first-principles calculations

Science.gov (United States)

Zhao, X. W.; Tian, Y. L.; Yue, W. W.; Chen, M. N.; Hu, G. C.; Ren, J. F.; Yuan, X. B.

2018-04-01

Adsorption properties of methanol molecule on graphene surface are studied both theoretically and experimentally. The adsorption geometrical structures, adsorption energies, band structures, density of states and the effective masses are obtained by means of first-principles calculations. It is found that the electronic characteristics and conductivity of graphene are sensitive to the methanol molecule adsorption. After adsorption of methanol molecule, bandgap appears. With the increasing of the adsorption distance, the bandgap, adsorption energy and effective mass of the adsorption system decreased, hence the resistivity of the system decreases gradually, these results are consistent with the experimental results. All these calculations and experiments indicate that the graphene-based sensors have a wide range of applications in detecting particular molecules.

Sample similarity analysis of angles of repose based on experimental results for DEM calibration

Science.gov (United States)

Tan, Yuan; Günthner, Willibald A.; Kessler, Stephan; Zhang, Lu

2017-06-01

As a fundamental material property, particle-particle friction coefficient is usually calculated based on angle of repose which can be obtained experimentally. In the present study, the bottomless cylinder test was carried out to investigate this friction coefficient of a kind of biomass material, i.e. willow chips. Because of its irregular shape and varying particle size distribution, calculation of the angle becomes less applicable and decisive. In the previous studies only one section of those uneven slopes is chosen in most cases, although standard methods in definition of a representable section are barely found. Hence, we presented an efficient and reliable method from the new technology, 3D scan, which was used to digitize the surface of heaps and generate its point cloud. Then, two tangential lines of any selected section were calculated through the linear least-squares regression (LLSR), such that the left and right angle of repose of a pile could be derived. As the next step, a certain sum of sections were stochastic selected, and calculations were repeated correspondingly in order to achieve sample of angles, which was plotted in Cartesian coordinates as spots diagram. Subsequently, different samples were acquired through various selections of sections. By applying similarities and difference analysis of these samples, the reliability of this proposed method was verified. Phased results provides a realistic criterion to reduce the deviation between experiment and simulation as a result of random selection of a single angle, which will be compared with the simulation results in the future.

Sample similarity analysis of angles of repose based on experimental results for DEM calibration

Directory of Open Access Journals (Sweden)

Tan Yuan

2017-01-01

Full Text Available As a fundamental material property, particle-particle friction coefficient is usually calculated based on angle of repose which can be obtained experimentally. In the present study, the bottomless cylinder test was carried out to investigate this friction coefficient of a kind of biomass material, i.e. willow chips. Because of its irregular shape and varying particle size distribution, calculation of the angle becomes less applicable and decisive. In the previous studies only one section of those uneven slopes is chosen in most cases, although standard methods in definition of a representable section are barely found. Hence, we presented an efficient and reliable method from the new technology, 3D scan, which was used to digitize the surface of heaps and generate its point cloud. Then, two tangential lines of any selected section were calculated through the linear least-squares regression (LLSR, such that the left and right angle of repose of a pile could be derived. As the next step, a certain sum of sections were stochastic selected, and calculations were repeated correspondingly in order to achieve sample of angles, which was plotted in Cartesian coordinates as spots diagram. Subsequently, different samples were acquired through various selections of sections. By applying similarities and difference analysis of these samples, the reliability of this proposed method was verified. Phased results provides a realistic criterion to reduce the deviation between experiment and simulation as a result of random selection of a single angle, which will be compared with the simulation results in the future.

Experimental Methods Applied in a Study of Stall Flutter in an Axial Flow Fan

Directory of Open Access Journals (Sweden)

John D. Gill

2004-01-01

Full Text Available Flutter testing is an integral part of aircraft gas turbine engine development. In typical flutter testing blade mounted sensors in the form of strain gages and casing mounted sensors in the form of light probes (NSMS are used. Casing mounted sensors have the advantage of being non-intrusive and can detect the vibratory response of each rotating blade. Other types of casing mounted sensors can also be used to detect flutter of rotating blades. In this investigation casing mounted high frequency response pressure transducers are used to characterize the part-speed stall flutter response of a single stage unshrouded axial-flow fan. These dynamic pressure transducers are evenly spaced around the circumference at a constant axial location upstream of the fan blade leading edge plane. The pre-recorded experimental data at 70% corrected speed is analyzed for the case where the fan is back-pressured into the stall flutter zone. The experimental data is analyzed using two probe and multi-probe techniques. The analysis techniques for each method are presented. Results from these two analysis methods indicate that flutter occurred at a frequency of 411 Hz with a dominant nodal diameter of 2. The multi-probe analysis technique is a valuable method that can be used to investigate the initiation of flutter in turbomachines.

Mixed-mode chaotic circuit with Wien-bridge configuration: The results of experimental verification

International Nuclear Information System (INIS)

Kilic, Recai

2007-01-01

In this paper, we deal with the experimentally implementation of inductorless Wien bridge-based mixed-mode chaotic circuit (MMCC) which is capable to exhibit both linear and nonlinear oscillations. The results of experimental implementation agree with the results of theoretical and computer simulation presented in literature. Since the proposed implementation of MMCC circuit uses different design blocks such as Wien bridge-based autonomous circuit part, CFOA (current feedback operational amplifier)-based floating inductance simulator, CFOA-based Chua's diode and switching mechanism, it offers very versatile chaotic circuit model for studying autonomous and nonautonomous chaotic dynamics

Development of method for experimental determination of wheel–rail contact forces and contact point position by using instrumented wheelset

International Nuclear Information System (INIS)

Bižić, Milan B; Petrović, Dragan Z; Tomić, Miloš C; Djinović, Zoran V

2017-01-01

This paper presents the development of a unique method for experimental determination of wheel–rail contact forces and contact point position by using the instrumented wheelset (IWS). Solutions of key problems in the development of IWS are proposed, such as the determination of optimal locations, layout, number and way of connecting strain gauges as well as the development of an inverse identification algorithm (IIA). The base for the solution of these problems is the wheel model and results of FEM calculations, while IIA is based on the method of blind source separation using independent component analysis. In the first phase, the developed method was tested on a wheel model and a high accuracy was obtained (deviations of parameters obtained with IIA and really applied parameters in the model are less than 2%). In the second phase, experimental tests on the real object or IWS were carried out. The signal-to-noise ratio was identified as the main influential parameter on the measurement accuracy. Тhе obtained results have shown that the developed method enables measurement of vertical and lateral wheel–rail contact forces Q and Y and their ratio Y / Q with estimated errors of less than 10%, while the estimated measurement error of contact point position is less than 15%. At flange contact and higher values of ratio Y / Q or Y force, the measurement errors are reduced, which is extremely important for the reliability and quality of experimental tests of safety against derailment of railway vehicles according to the standards UIC 518 and EN 14363. The obtained results have shown that the proposed method can be successfully applied in solving the problem of high accuracy measurement of wheel–rail contact forces and contact point position using IWS. (paper)

CFD and Experimental Studies on Wind Turbines in Complex Terrain by Improved Actuator Disk Method

Science.gov (United States)

Liu, Xin; Yan, Shu; Mu, Yanfei; Chen, Xinming; Shi, Shaoping

2017-05-01

In this paper, an onshore wind farm in mountainous area of southwest China was investigated through numerical and experimental methods. An improved actuator disk method, taking rotor data (i.e. blade geometry information, attack angle, blade pitch angle) into account, was carried out to investigate the flow characteristic of the wind farm, especially the wake developing behind the wind turbines. Comparing to the classic AD method and the situ measurements, the improved AD shows better agreements with the measurements. The turbine power was automatically predicted in CFD by blade element method, which agreed well with the measurement results. The study proved that the steady CFD simulation with improved actuator disk method was able to evaluate wind resource well and give good balance between computing efficiency and accuracy, in contrary to much more expensive computation methods such as actuator-line/actuator-surface transient model, or less accurate methods such as linear velocity reduction wake model.

Partition method and experimental validation for impact dynamics of flexible multibody system

Science.gov (United States)

Wang, J. Y.; Liu, Z. Y.; Hong, J. Z.

2018-06-01

The impact problem of a flexible multibody system is a non-smooth, high-transient, and strong-nonlinear dynamic process with variable boundary. How to model the contact/impact process accurately and efficiently is one of the main difficulties in many engineering applications. The numerical approaches being used widely in impact analysis are mainly from two fields: multibody system dynamics (MBS) and computational solid mechanics (CSM). Approaches based on MBS provide a more efficient yet less accurate analysis of the contact/impact problems, while approaches based on CSM are well suited for particularly high accuracy needs, yet require very high computational effort. To bridge the gap between accuracy and efficiency in the dynamic simulation of a flexible multibody system with contacts/impacts, a partition method is presented considering that the contact body is divided into two parts, an impact region and a non-impact region. The impact region is modeled using the finite element method to guarantee the local accuracy, while the non-impact region is modeled using the modal reduction approach to raise the global efficiency. A three-dimensional rod-plate impact experiment is designed and performed to validate the numerical results. The principle for how to partition the contact bodies is proposed: the maximum radius of the impact region can be estimated by an analytical method, and the modal truncation orders of the non-impact region can be estimated by the highest frequency of the signal measured. The simulation results using the presented method are in good agreement with the experimental results. It shows that this method is an effective formulation considering both accuracy and efficiency. Moreover, a more complicated multibody impact problem of a crank slider mechanism is investigated to strengthen this conclusion.

Comparison of OpenFOAM and EllipSys3D actuator line methods with (NEW) MEXICO results

Science.gov (United States)

Nathan, J.; Meyer Forsting, A. R.; Troldborg, N.; Masson, C.

2017-05-01

The Actuator Line Method exists for more than a decade and has become a well established choice for simulating wind rotors in computational fluid dynamics. Numerous implementations exist and are used in the wind energy research community. These codes were verified by experimental data such as the MEXICO experiment. Often the verification against other codes were made on a very broad scale. Therefore this study attempts first a validation by comparing two different implementations, namely an adapted version of SOWFA/OpenFOAM and EllipSys3D and also a verification by comparing against experimental results from the MEXICO and NEW MEXICO experiments.

[An experimental assessment of methods for applying intestinal sutures in intestinal obstruction].

Science.gov (United States)

Akhmadudinov, M G

1992-04-01

The results of various methods used in applying intestinal sutures in obturation were studied. Three series of experiments were conducted on 30 dogs--resection of the intestine after obstruction with the formation of anastomoses by means of double-row suture (Albert--Shmiden--Lambert) in the first series (10 dogs), by a single-row suture after V. M. Mateshchuk [correction of Mateshuku] in the second series, and bu a single-row stretching suture suggested by the author in the third series. The postoperative complications and the parameters of physical airtightness of the intestinal anastomosis were studied in dynamics in the experimental animals. The results of the study: incompetence of the anastomosis sutures in the first series 6, in the second 4, and in the third series one. Adhesions occurred in all animals of the first and second series and in 2 of the third series. Six dogs of the first series died, 4 of the second, and one of the third. Study of the dynamics of the results showed a direct connection of the complications with the parameters of the physical airtightness of the anastomosis, and the last-named with the method of the intestinal suture. Relatively better results were noted in formation of the anastomosis by means of our suggested stretshing continuous suture passed through the serous, muscular, and submucous coats of the intestine.

Experimental method for calculation of effective doses in interventional radiology; Metodo experimental para calculo de dosis efectivas en radiologia intervencionista

Energy Technology Data Exchange (ETDEWEB)

Herraiz Lblanca, M. D.; Diaz Romero, F.; Casares Magaz, O.; Garrido Breton, C.; Catalan Acosta, A.; Hernandez Armas, J.

2013-07-01

This paper proposes a method that allows you to calculate the effective dose in any interventional radiology procedure using an anthropomorphic mannequin Alderson RANDO and dosimeters TLD 100 chip. This method has been applied to an angio Radiology procedure: the biliary drainage. The objectives that have been proposed are: to) put together a method that, on an experimental basis, allows to know dosis en organs to calculate effective dose in complex procedures and b) apply the method to the calculation of the effective dose of biliary drainage. (Author)

Methods and experimental coefficients used in the computation of reactor shielding; Methodes et coefficients experimentaux pour le calcul des protections de reacteurs

Energy Technology Data Exchange (ETDEWEB)

Bourgeois, J; Lafore, P; Millot, J P; Rastoin, J; Vathaire, F de [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

1. The concept of an effective removal cross section has been developed in order more easily to compute reactor shielding thicknesses. We have built an experimental facility for the purpose of measuring effective removal cross sections, the value of which had not been published at that time. The first part of this paper describes the device or facility used, the computation method applied, and the results obtained. 2. Starting from this concept, we endeavored to define a removal cross section as a function of energy. This enabled us to use the method for computations bearing on the attenuation of fast neutrons of any spectrum. An experimental verification was carried out for the case of fission neutrons filtered by a substantial thickness of graphite. 3. Finally, we outline a computation method enabling us to determine the sources of captured gamma rays by the age theory and we give an example of the application in a composite shield. (author)Fren. [French] 1. La notion de section efficace effective de deplacement a ete introduite pour calculer commodement les epaisseurs de protection des reacteurs. Nous avons construit un dispositif experimental destine a mesurer les sections efficaces effectives de deplacement dont la valeur n'avait pas ete publiee a cette epoque. La premiere partie de cette communication decrit le dispositif utilise, la methode de calcul employee et les resultats obtenus. 2. A partir de cette notion, nous avons essaye de definir une section efficace de deplacement fonction de l'energie. Ceci permet d'utiliser la methode du deplacement pour des calculs d'attenuation de neutrons rapides dont le spectre est quelconque. Une verification experimentale a ete faite dans le cas de neutrons de fission filtres par une epaisseur notable de graphite. 3. Enfin une mde de calcul permettant de determiner les sources de gamma de capture par la theorie de l'age est exposee et un exemple d'application donne dans une protection composite. (auteur)

Comparison of ATHENA/RELAP results against ice experimental data

CERN Document Server

Moore-Richard, L

2002-01-01

In order to demonstrate the adequacy of the International Thermonuclear Experimental Reactor design from a safety stand point as well as investigating the behavior of two-phase flow phenomena during an ingress of coolant event, an integrated ICE test facility was constructed in Japan. The data generated from the ICE facility offers a valuable means to validate computer codes such as ATHENA /RELAP5, which is one of the codes used at the Idaho National Engineering And Environmental Laboratory (INEEL) to evaluate the safety of various fusion reactor concepts. In this paper we compared numerical results generated by the ATHENA code with corresponding test data from the ICE facility. Overall we found good agreement between the test data and the predicted results.

Experimental results for a novel rotary active magnetic regenerator

DEFF Research Database (Denmark)

Engelbrecht, Kurt; Eriksen, Dan; Bahl, Christian

2012-01-01

Active magnetic regenerator (AMR) refrigerators represent an alternative to vapor compression technology and have great potential in realizing cooling devices with high efficiency, which are highly desirable for a broad range of applications. The technology relies on the magnetocaloric effect...... in a solid refrigerant rather than the temperature change that occurs when a gas is compressed/expanded. This paper presents the general considerations for the design and construction of a high frequency rotary AMR device. Experimental results are presented at various cooling powers for a range of operating...

Cathodic protection simulation of above ground storage tank bottom: Experimental and numerical results

Energy Technology Data Exchange (ETDEWEB)

Schultz, Marcelo [Inspection Department, Rio de Janeiro Refinery - REDUC, Petrobras, Rio de Janeiro (Brazil); Brasil, Simone L.D.C. [Chemistry School, Federal University of Rio de Janeiro, UFRJ, Rio de Janeiro (Brazil); Baptista, Walmar [Corrosion Department, Research Centre - CENPES, Petrobras (Brazil); Miranda, Luiz de [Materials and Metallurgical Engineering Program, COPPE, UFRJ, Rio de Janeiro (Brazil); Brito, Rosane F. [Corrosion Department, Research Centre, CENPES, Petrobras, Rio de Janeiro (Brazil)

2004-07-01

The deterioration history of Above ground Storage Tanks (AST) of Petrobras' refineries - shows that the great incidence of corrosion in the AST bottom is at the external side. This is a problem in the disposability of storage crude oil and other final products. At this refinery, all AST's are built over a concrete base with a lot of pile to support the structure and distribute the charge homogeneously. Because of this it is very difficult to use cathodic protection as an anti-corrosive method for each one of these tanks. This work presents an alternative cathodic protection system to protect the external side of the tank bottom using a new metallic bottom, placed at different distance from the original one. The space between the two bottoms was filled with one of two kinds of soils, sand or clay, more conductive than the concrete. Using a prototype tank it was studied the potential distributions over the new tank bottom for different system parameters, as soil resistivity, number and position of anodes localized in the old bottom. These experimental results were compared to numerical simulations, carried out using a software based on the Boundary Element Method. The computer simulation validates this protection method, confirming to be a very useful tool to define the optimized cathodic protection system configuration. (authors)

Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures.

Science.gov (United States)

Nuyens, Filip; Deleuze, Jory; Maurage, Pierre; Griffiths, Mark D; Kuss, Daria J; Billieux, Joël

2016-06-01

Background and aims Multiplayer Online Battle Arena (MOBA) games have become the most popular type of video games played worldwide, superseding the playing of Massively Multiplayer Online Role-Playing Games and First-Person Shooter games. However, empirical studies focusing on the use and abuse of MOBA games are still very limited, particularly regarding impulsivity, which is an indicator of addictive states but has not yet been explored in MOBA games. In this context, the objective of the present study is to explore the associations between impulsivity and symptoms of addictive use of MOBA games in a sample of highly involved League of Legends (LoL, currently the most popular MOBA game) gamers. Methods Thirty-six LoL gamers were recruited and completed both experimental (Single Key Impulsivity Paradigm) and self-reported impulsivity assessments (s-UPPS-P Impulsive Behavior Scale, Barratt Impulsiveness Scale), in addition to an assessment of problematic video game use (Problematic Online Gaming Questionnaire). Results Results showed links between impulsivity-related constructs and signs of excessive MOBA game involvement. Findings indicated that impaired ability to postpone rewards in an experimental laboratory task was strongly related to problematic patterns of MOBA game involvement. Although less consistent, several associations were also found between self-reported impulsivity traits and signs of excessive MOBA game involvement. Conclusions Despite these results are preliminary and based upon a small (self-selected) sample, the present study highlights potential psychological factors related to the addictive use of MOBA games.

Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures

Science.gov (United States)

Nuyens, Filip; Deleuze, Jory; Maurage, Pierre; Griffiths, Mark D.; Kuss, Daria J.; Billieux, Joël

2016-01-01

Background and aims Multiplayer Online Battle Arena (MOBA) games have become the most popular type of video games played worldwide, superseding the playing of Massively Multiplayer Online Role-Playing Games and First-Person Shooter games. However, empirical studies focusing on the use and abuse of MOBA games are still very limited, particularly regarding impulsivity, which is an indicator of addictive states but has not yet been explored in MOBA games. In this context, the objective of the present study is to explore the associations between impulsivity and symptoms of addictive use of MOBA games in a sample of highly involved League of Legends (LoL, currently the most popular MOBA game) gamers. Methods Thirty-six LoL gamers were recruited and completed both experimental (Single Key Impulsivity Paradigm) and self-reported impulsivity assessments (s-UPPS-P Impulsive Behavior Scale, Barratt Impulsiveness Scale), in addition to an assessment of problematic video game use (Problematic Online Gaming Questionnaire). Results Results showed links between impulsivity-related constructs and signs of excessive MOBA game involvement. Findings indicated that impaired ability to postpone rewards in an experimental laboratory task was strongly related to problematic patterns of MOBA game involvement. Although less consistent, several associations were also found between self-reported impulsivity traits and signs of excessive MOBA game involvement. Conclusions Despite these results are preliminary and based upon a small (self-selected) sample, the present study highlights potential psychological factors related to the addictive use of MOBA games. PMID:27156376

Environmental assessment of a uranium experimental rock blasting in Portugal, using geophysical and hydrogeological methods

International Nuclear Information System (INIS)

Ramalho, E C; Midões, C; Costa, A; Lourenço, M C; Monteiro Santos, F A

2012-01-01

The Nisa uranium deposit, located in Central Portugal, has been known since the late 1960s. Some areas were explored at that time. Today, a few open pits and dumps remain in place and are a concern to local authorities. To assess the geoenvironmental problems caused by the main mining exploration composed of an experimental rock blasting, 3D electrical conductivity and resistivity models were made to develop a hydrogeological model to understand the possibility of contaminants transportation, such as uranium, from the dumps towards a dam located nearby. These 3D models were the support to show alteration layer thickness variations and fault zones at depths controlling groundwater circulation. Spectrometric surveys were also carried out and correlated with geology and geoelectrical structure. All this information was used in the construction of the 3D steady state hydrogeological model of the experimental rock blasting of Nisa. In this model, groundwater flow and the contaminant pathways were simulated. Some areas have very high radioactive values resulting from the geological formation characteristics and old dumps. However, results of the environmental assessment using geophysical and hydrogeological methods point to a critical situation restricted only to the area of the experimental rock blasting of the Nisa uranium deposit and its dumps. (paper)

Photoionization microscopy: Hydrogenic theory in semiparabolic coordinates and comparison with experimental results

Science.gov (United States)

Kalaitzis, P.; Danakas, S.; Lépine, F.; Bordas, C.; Cohen, S.

2018-05-01

Photoionization microscopy (PM) is an experimental method allowing for high-resolution measurements of the electron current probability density in the case of photoionization of an atom in an external uniform static electric field. PM is based on high-resolution velocity-map imaging and offers the unique opportunity to observe the quantum oscillatory spatial structure of the outgoing electron flux. We present the basic elements of the quantum-mechanical theoretical framework of PM for hydrogenic systems near threshold. Our development is based on the computationally more convenient semiparabolic coordinate system. Theoretical results are first subjected to a quantitative comparison with hydrogenic images corresponding to quasibound states and a qualitative comparison with nonresonant images of multielectron atoms. Subsequently, particular attention is paid on the structure of the electron's momentum distribution transversely to the static field (i.e., of the angularly integrated differential cross-section as a function of electron energy and radius of impact on the detector). Such 2D maps provide at a glance a complete picture of the peculiarities of the differential cross-section over the entire near-threshold energy range. Hydrogenic transverse momentum distributions are computed for the cases of the ground and excited initial states and single- and two-photon ionization schemes. Their characteristics of general nature are identified by comparing the hydrogenic distributions among themselves, as well as with a presently recorded experimental distribution concerning the magnesium atom. Finally, specificities attributed to different target atoms, initial states, and excitation scenarios are also discussed, along with directions of further work.

Mixed-mode chaotic circuit with Wien-bridge configuration: The results of experimental verification

Energy Technology Data Exchange (ETDEWEB)

Kilic, Recai [Erciyes University, Department of Electronic Engineering, 38039 Kayseri (Turkey)]. E-mail: kilic@erciyes.edu.tr

2007-05-15

In this paper, we deal with the experimentally implementation of inductorless Wien bridge-based mixed-mode chaotic circuit (MMCC) which is capable to exhibit both linear and nonlinear oscillations. The results of experimental implementation agree with the results of theoretical and computer simulation presented in literature. Since the proposed implementation of MMCC circuit uses different design blocks such as Wien bridge-based autonomous circuit part, CFOA (current feedback operational amplifier)-based floating inductance simulator, CFOA-based Chua's diode and switching mechanism, it offers very versatile chaotic circuit model for studying autonomous and nonautonomous chaotic dynamics.

Experimental research and use of finite elements method on mechanical behaviors of honeycomb structures assembled with epoxy-based adhesives reinforced with nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Akkus, Harun [Technical Sciences Vocational School, Amasya University, Amasya (Turkmenistan); Duzcukoglu, Hayrettin; Sahin, Omer Sinan [Mechanical Engineering Department, Selcuk University, Selcuk (Turkmenistan)

2017-01-15

This study utilized experimental and finite element methods to investigate the mechanical behavior of aluminum honeycomb structures under compression. Aluminum honeycomb composite structures were subjected to pressing experiments according to the standard ASTM C365. Resistive forces in response to compression and maximum compressive force values were measured. Structural damage was observed. In the honeycomb structure, the cell width decreased as the compressive force increased. Results obtained with finite element models generated using ANSYS Workbench 15 were validated. Experimental results paralleled the finite element modeling results. The ANSYS results were approximately 85 % reliable.

Experimental results from a flowing-lithium target

International Nuclear Information System (INIS)

Annese, C.E.; Schwartz, K.E.

1982-01-01

Hydraulic stability of a free surface lithium jet was demonstrated at 260 0 C and from the middle-vacuum region of 0.01 Pa (10 - 4 Torr) up to 124 kPa (18 psia). The jet is formed by flowing lithium at rates to 0.04 m 3 /s (600 GPM) through a precisely defined nozzle which directs the flow along a curved wall where velocities of up to 17 m/s are attained. This nozzle and curved wall configuration form the basis of the Fusion Materials Irradiation Test (FMIT) Facility lithium target. A full-size experimental model of this target is presently under test with flowing lithium in the Experimental Lithium System (ELS). The FMIT is being developed for the Department of Energy by the Westinghouse Hanford Company at the Hanford Engineering Development Laboratory

Primarily Experimental Results for a W Wire Array Z Pinch

International Nuclear Information System (INIS)

Kuai Bin; Aici, Qiu; Wang Liangping; Zeng Zhengzhong; Wang Wensheng; Cong Peitian; Gai Tongyang; Wei Fuli; Guo Ning; Zhang Zhong

2006-01-01

Primarily experimental results are given for a W wire array Z pinch imploded with up to 2 MA in 100 ns on a Qiangguang-I pulsed power generator. The configuration and parameters of the generator, the W wire array load assembly and the diagnostic system for the experiment are described. The total X-ray energy has been obtained with a averaged power of X-ray radiation of 1.28 TW

Plasma exhaust purification by thermal swing adsorption: Experimental results and modeling

International Nuclear Information System (INIS)

Ricapito, I.; Malara, R.C.

1996-01-01

For several years at the Joint Research Centre-Ispra laboratories, cyclic adsorption processes have been developed for the purification of the plasma exhaust stream of a deuterium-tritium fusion reactor. A purification process consisting of two coupled thermal swing adsorption systems seemed to be the most convenient process. In this context, a screening study was carried out to select the most suitable adsorbent materials and appropriate working temperatures. This was mainly done by experimental measurements of adsorption isotherms of the single components of the plasma exhaust stream and by a careful evaluation of the multicomponent adsorption equilibria. Experiments on adsorption dynamics were carried out in a pilot plant to demonstrate the feasibility and to evaluate the performance of the process. The experimental apparatus was designed to treat gas mixture flow rates up to 20 to 30 standard temperature and pressure l/h. A mathematical model was developed and tested against the experimental results to describe the adsorption process and, in particular, to evaluate and to optimize the process cycle time. 27 refs., 4 figs., 9 tabs

Experimental research on intraocular aqueous flow by PIV method.

Science.gov (United States)

Yang, Hongyu; Song, Hongfang; Mei, Xi; Li, Lin; Fu, Xineng; Zhang, Mindi; Liu, Zhicheng

2013-10-21

Aqueous humor flows regularly from posterior chamber to anterior chamber, and this flow much involves intraocular pressure, the eye tissue nutrition and metabolism. To visualize and measure the intraocular flow regular pattern of aqueous humor. Intraocular flow in the vitro eyeball is driven to simulate the physiological aqueous humor flow, and the flow field is measured by Particle Image Velocimetry(PIV). Fluorescent particle solution of a certain concentration was infused into the root of Posterior Chamber(PC) of vitro rabbit eye to simulate the generation of aqueous and was drained out at a certain hydrostatic pressure from the angle of Anterior Chamber(AC) to represent the drainage of aqueous. PIV method was used to record and calculate the flow on the midsagittal plane of the eyeball. Velocity vector distribution in AC has been obtained, and the distribution shows symmetry feature to some extent. Fluorescent particle solution first fills the PC as it is continuously infused, then surges into AC through the pupil, flows upwards toward the central cornea, reflecting and scattering, and eventually converges along the inner cornea surface towards the outflow points at the periphery of the eyeball. Velocity values around the pupillary margin are within the range of 0.008-0.012 m/s, which are close to theoretical values of 0.0133 m/s, under the driving rate of 100 μl/min. Flow field of aqueous humor can be measured by PIV method, which makes it possible to study the aqueous humor dynamics by experimental method. Our study provides a basis for experimental research on aqueous humor flow; further, it possibly helps to diagnose and treat eye diseases as shear force damage of ocular tissues and destructions on corneal endothelial cells from the point of intraocular flow field.

Experimental results on elongation control using dynamic input allocation at FTU

International Nuclear Information System (INIS)

Varano, G.; Boncagni, L.; Galeani, S.; Granucci, G.; Vitale, V.; Zaccarian, L.

2011-01-01

We report on the experimental results related to a recently proposed control scheme for the regulation of plasma elongation using the poloidal field coils available at FTU, already used for the horizontal position control. The proposed technique allows to realize elongation regulation as a secondary task using the same poloidal coils.

Energy-resolved computed tomography: first experimental results

International Nuclear Information System (INIS)

Shikhaliev, Polad M

2008-01-01

First experimental results with energy-resolved computed tomography (CT) are reported. The contrast-to-noise ratio (CNR) in CT has been improved with x-ray energy weighting for the first time. Further, x-ray energy weighting improved the CNR in material decomposition CT when applied to CT projections prior to dual-energy subtraction. The existing CT systems use an energy (charge) integrating x-ray detector that provides a signal proportional to the energy of the x-ray photon. Thus, the x-ray photons with lower energies are scored less than those with higher energies. This underestimates contribution of lower energy photons that would provide higher contrast. The highest CNR can be achieved if the x-ray photons are scored by a factor that would increase as the x-ray energy decreases. This could be performed by detecting each x-ray photon separately and measuring its energy. The energy selective CT data could then be saved, and any weighting factor could be applied digitally to a detected x-ray photon. The CT system includes a photon counting detector with linear arrays of pixels made from cadmium zinc telluride (CZT) semiconductor. A cylindrical phantom with 10.2 cm diameter made from tissue-equivalent material was used for CT imaging. The phantom included contrast elements representing calcifications, iodine, adipose and glandular tissue. The x-ray tube voltage was 120 kVp. The energy selective CT data were acquired, and used to generate energy-weighted and material-selective CT images. The energy-weighted and material decomposition CT images were generated using a single CT scan at a fixed x-ray tube voltage. For material decomposition the x-ray spectrum was digitally spilt into low- and high-energy parts and dual-energy subtraction was applied. The x-ray energy weighting resulted in CNR improvement of calcifications and iodine by a factor of 1.40 and 1.63, respectively, as compared to conventional charge integrating CT. The x-ray energy weighting was also applied

Some new experimental results on the Zr-Nb-Fe system

Energy Technology Data Exchange (ETDEWEB)

Ramos, C. [Departamento de Fisica - CAC - Comision Nacional de Energia Atomica, Av. Gral Paz 1499, (1650) San Martin, Buenos Aires (Argentina)]. E-mail: ciramos@cnea.gov.ar; Saragovi, C. [Departamento de Fisica - CAC - Comision Nacional de Energia Atomica, Av. Gral Paz 1499, (1650) San Martin, Buenos Aires (Argentina); Granovsky, M.S. [Departamento de Materiales - CAC - Comision Nacional de Energia Atomica, Av. Gral Paz 1499, (1650) San Martin, Buenos Aires (Argentina)

2007-06-30

The scope of this study is the identification and characterization of intermetallic phases and their binary and ternary fields in the Zr-Nb-Fe phase diagram. A construction of the central region of the phase diagram at 900 {sup o}C was proposed using new experimental results obtained by optical and scanning electron microscopies, X-ray diffraction and microprobe analysis. In addition to the well-known Laves C15-type (ZrNb)Fe{sub 2} phase (the polytypic C14 and C36 structures were not detected in the studied compositions), another Laves C14-type phase was found (Zr(NbFe){sub 2}). Watson and Bennett maps helped to predict the occurrence of both of these phases. Moreover, the validity of the Pettifor prediction model for Laves phases in pseudobinary systems with transition elements was checked, verifying the obtained experimental results in the Zr-Nb-Fe system. On the other hand it was determined that the Zr-Nb-Fe ternary system at 900 {sup o}C, as it happens in the binary Zr-Nb system, would have a miscibility gap ({beta}-Zr + {beta}-Nb) in the 25-70 at.% Nb composition range, accepting up to 3 at.% Fe approximately.

Comprehensive Evaluation of Algal Biofuel Production: Experimental and Target Results

Directory of Open Access Journals (Sweden)

Colin M. Beal

2012-06-01

Full Text Available Worldwide, algal biofuel research and development efforts have focused on increasing the competitiveness of algal biofuels by increasing the energy and financial return on investments, reducing water intensity and resource requirements, and increasing algal productivity. In this study, analyses are presented in each of these areas—costs, resource needs, and productivity—for two cases: (1 an Experimental Case, using mostly measured data for a lab-scale system, and (2 a theorized Highly Productive Case that represents an optimized commercial-scale production system, albeit one that relies on full-price water, nutrients, and carbon dioxide. For both cases, the analysis described herein concludes that the energy and financial return on investments are less than 1, the water intensity is greater than that for conventional fuels, and the amounts of required resources at a meaningful scale of production amount to significant fractions of current consumption (e.g., nitrogen. The analysis and presentation of results highlight critical areas for advancement and innovation that must occur for sustainable and profitable algal biofuel production can occur at a scale that yields significant petroleum displacement. To this end, targets for energy consumption, production cost, water consumption, and nutrient consumption are presented that would promote sustainable algal biofuel production. Furthermore, this work demonstrates a procedure and method by which subsequent advances in technology and biotechnology can be framed to track progress.

Coherent versus incoherent resonant emission: an experimental method for easy discrimination and measurement

Science.gov (United States)

Ceccherini, S.; Colocci, M.; Gurioli, M.; Bogani, F.

1998-11-01

The distinction between the coherent and the incoherent component of the radiation emitted from resonantly excited material systems is difficult experimentally, particularly when ultra-short optical pulses are used for excitation. We propose an experimental procedure allowing an easy measurement of the two components. The method is completely general and applicable to any kind of physical system; its feasibility is demonstrated on the resonant emission from excitons in a semiconductor quantum well.

Experimental study on two-dimensional film flow with local measurement methods

Energy Technology Data Exchange (ETDEWEB)

Yang, Jin-Hwa, E-mail: evo03@snu.ac.kr [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon 305-600 (Korea, Republic of); Cho, Hyoung-Kyu [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Kim, Seok [Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon 305-600 (Korea, Republic of); Euh, Dong-Jin, E-mail: djeuh@kaeri.re.kr [Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon 305-600 (Korea, Republic of); Park, Goon-Cherl [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of)

2015-12-01

Highlights: • An experimental study on the two-dimensional film flow with lateral air injection was performed. • The ultrasonic thickness gauge was used to measure the local liquid film thickness. • The depth-averaged PIV (Particle Image Velocimetry) method was applied to measure the local liquid film velocity. • The uncertainty of the depth-averaged PIV was quantified with a validation experiment. • Characteristics of two-dimensional film flow were classified following the four different flow patterns. - Abstract: In an accident condition of a nuclear reactor, multidimensional two-phase flows may occur in the reactor vessel downcomer and reactor core. Therefore, those have been regarded as important issues for an advanced thermal-hydraulic safety analysis. In particular, the multi-dimensional two-phase flow in the upper downcomer during the reflood phase of large break loss of coolant accident appears with an interaction between a downward liquid and a transverse gas flow, which determines the bypass flow rate of the emergency core coolant and subsequently, the reflood coolant flow rate. At present, some thermal-hydraulic analysis codes incorporate multidimensional modules for the nuclear reactor safety analysis. However, their prediction capability for the two-phase cross flow in the upper downcomer has not been validated sufficiently against experimental data based on local measurements. For this reason, an experimental study was carried out for the two-phase cross flow to clarify the hydraulic phenomenon and provide local measurement data for the validation of the computational tools. The experiment was performed in a 1/10 scale unfolded downcomer of Advanced Power Reactor 1400 (APR1400). Pitot tubes, a depth-averaged PIV method and ultrasonic thickness gauge were applied for local measurement of the air velocity, the liquid film velocity and the liquid film thickness, respectively. The uncertainty of the depth-averaged PIV method for the averaged

Experimental study on two-dimensional film flow with local measurement methods

International Nuclear Information System (INIS)

Yang, Jin-Hwa; Cho, Hyoung-Kyu; Kim, Seok; Euh, Dong-Jin; Park, Goon-Cherl

2015-01-01

Highlights: • An experimental study on the two-dimensional film flow with lateral air injection was performed. • The ultrasonic thickness gauge was used to measure the local liquid film thickness. • The depth-averaged PIV (Particle Image Velocimetry) method was applied to measure the local liquid film velocity. • The uncertainty of the depth-averaged PIV was quantified with a validation experiment. • Characteristics of two-dimensional film flow were classified following the four different flow patterns. - Abstract: In an accident condition of a nuclear reactor, multidimensional two-phase flows may occur in the reactor vessel downcomer and reactor core. Therefore, those have been regarded as important issues for an advanced thermal-hydraulic safety analysis. In particular, the multi-dimensional two-phase flow in the upper downcomer during the reflood phase of large break loss of coolant accident appears with an interaction between a downward liquid and a transverse gas flow, which determines the bypass flow rate of the emergency core coolant and subsequently, the reflood coolant flow rate. At present, some thermal-hydraulic analysis codes incorporate multidimensional modules for the nuclear reactor safety analysis. However, their prediction capability for the two-phase cross flow in the upper downcomer has not been validated sufficiently against experimental data based on local measurements. For this reason, an experimental study was carried out for the two-phase cross flow to clarify the hydraulic phenomenon and provide local measurement data for the validation of the computational tools. The experiment was performed in a 1/10 scale unfolded downcomer of Advanced Power Reactor 1400 (APR1400). Pitot tubes, a depth-averaged PIV method and ultrasonic thickness gauge were applied for local measurement of the air velocity, the liquid film velocity and the liquid film thickness, respectively. The uncertainty of the depth-averaged PIV method for the averaged

Characteristics of prompt fission gamma-ray emission - Experimental results and predictions

International Nuclear Information System (INIS)

Oberstedt, Andreas; Billnert, Robert; Oberstedt, Stephan

2014-01-01

Systematics from 2001, describing prompt fission gamma-ray spectra (PFGS) characteristics as function of mass and atomic number of the fissioning system, has been revisited and parameters have been revised based on recent experimental results. Although originally expressed for spontaneous and thermal neutron-induced fission, validity for fast neutrons was assumed and applied to predict PFGS characteristics for the reaction n + 238 U up to incident neutron energies of E n = 20 MeV. The results from this work are in good agreement with corresponding results from both model calculations and experiments. (authors)

An experimental-numerical method for comparative analysis of joint prosthesis; Un metodo numerico-experimental para el analisis comparativo de protesis articulares

Energy Technology Data Exchange (ETDEWEB)

Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

2001-07-01

The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs.

Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results.

Science.gov (United States)

Humada, Ali M; Hojabri, Mojgan; Sulaiman, Mohd Herwan Bin; Hamada, Hussein M; Ahmed, Mushtaq N

2016-01-01

A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions.

Theoretical and Experimental Results Regarding LENR/CF

International Nuclear Information System (INIS)

Robert W. Bass; Wm. Stan Gleeson

2000-01-01

We challenge the predominant view that low-energy nuclear reactions (LENRs) are prohibited by standard quantum mechanics (QM). This view, supposedly based on standard nuclear theory, need not apply in condensed-matter environments. These considerations indicate that seemingly novel experimental evidence of rapid aneutronic bulk-process transmutation, at extraordinarily low-energy levels, in a simple electrochemical reactor, can occur. This explains: (a) induced rapid decay of radioactive thorium into stable nuclides, e.g., Cu and (b) resulting, anomalous distribution of Cu isotopes. We reexamine arguments of Peebles cited as evidence that standard QM 'forbids' cold fusion (CF). We note oversimplifications in those and present an alternative, more sophisticated calculation (see Bass, Refs. 3 through 8) demonstrating that conventional wisdom about impenetrability of the 'Coulomb barrier' fails as a result of periodic-order-induced resonance. We also examine empirical evidence. In three independent tests of an LENR electrolysis cell, using different I-V-T (current/voltage/time) protocols, the percentage of radiation reduction (RR) transmutation achieved η=[23%, 50%, 83%] versus expended energy E=[0.6535, 32.5, 74.6] (Watt-hours), obtained by numerical integration of recorded product I · V for processing time T, provides near-perfect straight-line correlation: η=α·E + η 0 , α=0.8105, η 0 =22.888, (0.65 < E < 0.75)

Method to deterministically study photonic nanostructures in different experimental instruments.

Science.gov (United States)

Husken, B H; Woldering, L A; Blum, C; Vos, W L

2009-01-01

We describe an experimental method to recover a single, deterministically fabricated nanostructure in various experimental instruments without the use of artificially fabricated markers, with the aim to study photonic structures. Therefore, a detailed map of the spatial surroundings of the nanostructure is made during the fabrication of the structure. These maps are made using a series of micrographs with successively decreasing magnifications. The graphs reveal intrinsic and characteristic geometric features that can subsequently be used in different setups to act as markers. As an illustration, we probe surface cavities with radii of 65 nm on a silica opal photonic crystal with various setups: a focused ion beam workstation; a scanning electron microscope (SEM); a wide field optical microscope and a confocal microscope. We use cross-correlation techniques to recover a small area imaged with the SEM in a large area photographed with the optical microscope, which provides a possible avenue to automatic searching. We show how both structural and optical reflectivity data can be obtained from one and the same nanostructure. Since our approach does not use artificial grids or markers, it is of particular interest for samples whose structure is not known a priori, like samples created solely by self-assembly. In addition, our method is not restricted to conducting samples.

A comparative study to investigate burnup in research reactor fuel using two independent experimental methods

International Nuclear Information System (INIS)

Iqbal, M.; Mehmood, T.; Ayazuddin, S.K.; Salahuddin, A.; Pervez, S.

2001-01-01

Two independent experimental methods have been used for the comparative study of fuel burnup measurement in low enriched uranium, plate type research reactor. In the first method a gamma ray activity ratio method was employed. An experimental setup was established for gamma ray scanning using prior calibrated high purity germanium detector. The computer software KORIGEN gave the theoretical support. In the second method reactivity difference technique was used. At the same location in the same core configuration the fresh and burned fuel element's reactivity worth was estimated. For theoretical estimated curve, group cross-sections were generated using computer code WIMS-D/4, and three dimensional modeling was made by computer code CITATION. The measured burnup of different fuel elements using these methods were found to be in good agreement

Comparison of OpenFOAM and EllipSys3D actuator line methods with (NEW) MEXICO results

International Nuclear Information System (INIS)

Nathan, J; Masson, C; Meyer Forsting, A R; Troldborg, N

2017-01-01

The Actuator Line Method exists for more than a decade and has become a well established choice for simulating wind rotors in computational fluid dynamics. Numerous implementations exist and are used in the wind energy research community. These codes were verified by experimental data such as the MEXICO experiment. Often the verification against other codes were made on a very broad scale. Therefore this study attempts first a validation by comparing two different implementations, namely an adapted version of SOWFA/OpenFOAM and EllipSys3D and also a verification by comparing against experimental results from the MEXICO and NEW MEXICO experiments. (paper)

A method for modeling laterally asymmetric proton beamlets resulting from collimation

Energy Technology Data Exchange (ETDEWEB)

Gelover, Edgar; Wang, Dongxu; Flynn, Ryan T.; Hyer, Daniel E. [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Hill, Patrick M. [Department of Human Oncology, University of Wisconsin, 600 Highland Avenue, Madison, Wisconsin 53792 (United States); Gao, Mingcheng; Laub, Steve; Pankuch, Mark [Division of Medical Physics, CDH Proton Center, 4455 Weaver Parkway, Warrenville, Illinois 60555 (United States)

2015-03-15

Purpose: To introduce a method to model the 3D dose distribution of laterally asymmetric proton beamlets resulting from collimation. The model enables rapid beamlet calculation for spot scanning (SS) delivery using a novel penumbra-reducing dynamic collimation system (DCS) with two pairs of trimmers oriented perpendicular to each other. Methods: Trimmed beamlet dose distributions in water were simulated with MCNPX and the collimating effects noted in the simulations were validated by experimental measurement. The simulated beamlets were modeled analytically using integral depth dose curves along with an asymmetric Gaussian function to represent fluence in the beam’s eye view (BEV). The BEV parameters consisted of Gaussian standard deviations (sigmas) along each primary axis (σ{sub x1},σ{sub x2},σ{sub y1},σ{sub y2}) together with the spatial location of the maximum dose (μ{sub x},μ{sub y}). Percent depth dose variation with trimmer position was accounted for with a depth-dependent correction function. Beamlet growth with depth was accounted for by combining the in-air divergence with Hong’s fit of the Highland approximation along each axis in the BEV. Results: The beamlet model showed excellent agreement with the Monte Carlo simulation data used as a benchmark. The overall passing rate for a 3D gamma test with 3%/3 mm passing criteria was 96.1% between the analytical model and Monte Carlo data in an example treatment plan. Conclusions: The analytical model is capable of accurately representing individual asymmetric beamlets resulting from use of the DCS. This method enables integration of the DCS into a treatment planning system to perform dose computation in patient datasets. The method could be generalized for use with any SS collimation system in which blades, leaves, or trimmers are used to laterally sharpen beamlets.

A method for modeling laterally asymmetric proton beamlets resulting from collimation

International Nuclear Information System (INIS)

Gelover, Edgar; Wang, Dongxu; Flynn, Ryan T.; Hyer, Daniel E.; Hill, Patrick M.; Gao, Mingcheng; Laub, Steve; Pankuch, Mark

2015-01-01

Purpose: To introduce a method to model the 3D dose distribution of laterally asymmetric proton beamlets resulting from collimation. The model enables rapid beamlet calculation for spot scanning (SS) delivery using a novel penumbra-reducing dynamic collimation system (DCS) with two pairs of trimmers oriented perpendicular to each other. Methods: Trimmed beamlet dose distributions in water were simulated with MCNPX and the collimating effects noted in the simulations were validated by experimental measurement. The simulated beamlets were modeled analytically using integral depth dose curves along with an asymmetric Gaussian function to represent fluence in the beam’s eye view (BEV). The BEV parameters consisted of Gaussian standard deviations (sigmas) along each primary axis (σ x1 ,σ x2 ,σ y1 ,σ y2 ) together with the spatial location of the maximum dose (μ x ,μ y ). Percent depth dose variation with trimmer position was accounted for with a depth-dependent correction function. Beamlet growth with depth was accounted for by combining the in-air divergence with Hong’s fit of the Highland approximation along each axis in the BEV. Results: The beamlet model showed excellent agreement with the Monte Carlo simulation data used as a benchmark. The overall passing rate for a 3D gamma test with 3%/3 mm passing criteria was 96.1% between the analytical model and Monte Carlo data in an example treatment plan. Conclusions: The analytical model is capable of accurately representing individual asymmetric beamlets resulting from use of the DCS. This method enables integration of the DCS into a treatment planning system to perform dose computation in patient datasets. The method could be generalized for use with any SS collimation system in which blades, leaves, or trimmers are used to laterally sharpen beamlets

A method for modeling laterally asymmetric proton beamlets resulting from collimation

Science.gov (United States)

Gelover, Edgar; Wang, Dongxu; Hill, Patrick M.; Flynn, Ryan T.; Gao, Mingcheng; Laub, Steve; Pankuch, Mark; Hyer, Daniel E.

2015-01-01

Purpose: To introduce a method to model the 3D dose distribution of laterally asymmetric proton beamlets resulting from collimation. The model enables rapid beamlet calculation for spot scanning (SS) delivery using a novel penumbra-reducing dynamic collimation system (DCS) with two pairs of trimmers oriented perpendicular to each other. Methods: Trimmed beamlet dose distributions in water were simulated with MCNPX and the collimating effects noted in the simulations were validated by experimental measurement. The simulated beamlets were modeled analytically using integral depth dose curves along with an asymmetric Gaussian function to represent fluence in the beam’s eye view (BEV). The BEV parameters consisted of Gaussian standard deviations (sigmas) along each primary axis (σx1,σx2,σy1,σy2) together with the spatial location of the maximum dose (μx,μy). Percent depth dose variation with trimmer position was accounted for with a depth-dependent correction function. Beamlet growth with depth was accounted for by combining the in-air divergence with Hong’s fit of the Highland approximation along each axis in the BEV. Results: The beamlet model showed excellent agreement with the Monte Carlo simulation data used as a benchmark. The overall passing rate for a 3D gamma test with 3%/3 mm passing criteria was 96.1% between the analytical model and Monte Carlo data in an example treatment plan. Conclusions: The analytical model is capable of accurately representing individual asymmetric beamlets resulting from use of the DCS. This method enables integration of the DCS into a treatment planning system to perform dose computation in patient datasets. The method could be generalized for use with any SS collimation system in which blades, leaves, or trimmers are used to laterally sharpen beamlets. PMID:25735287

A hierarchy of models for simulating experimental results from a 3D heterogeneous porous medium

Science.gov (United States)

Vogler, Daniel; Ostvar, Sassan; Paustian, Rebecca; Wood, Brian D.

2018-04-01

In this work we examine the dispersion of conservative tracers (bromide and fluorescein) in an experimentally-constructed three-dimensional dual-porosity porous medium. The medium is highly heterogeneous (σY2 = 5.7), and consists of spherical, low-hydraulic-conductivity inclusions embedded in a high-hydraulic-conductivity matrix. The bimodal medium was saturated with tracers, and then flushed with tracer-free fluid while the effluent breakthrough curves were measured. The focus for this work is to examine a hierarchy of four models (in the absence of adjustable parameters) with decreasing complexity to assess their ability to accurately represent the measured breakthrough curves. The most information-rich model was (1) a direct numerical simulation of the system in which the geometry, boundary and initial conditions, and medium properties were fully independently characterized experimentally with high fidelity. The reduced-information models included; (2) a simplified numerical model identical to the fully-resolved direct numerical simulation (DNS) model, but using a domain that was one-tenth the size; (3) an upscaled mobile-immobile model that allowed for a time-dependent mass-transfer coefficient; and, (4) an upscaled mobile-immobile model that assumed a space-time constant mass-transfer coefficient. The results illustrated that all four models provided accurate representations of the experimental breakthrough curves as measured by global RMS error. The primary component of error induced in the upscaled models appeared to arise from the neglect of convection within the inclusions. We discuss the necessity to assign value (via a utility function or other similar method) to outcomes if one is to further select from among model options. Interestingly, these results suggested that the conventional convection-dispersion equation, when applied in a way that resolves the heterogeneities, yields models with high fidelity without requiring the imposition of a more

Experimental results of some cluster tests in NSRR

International Nuclear Information System (INIS)

Kobayashi, Shinsho; Ohnishi, Nobuaki; Yoshimura, Tomio; Lussie, W.G.

1978-01-01

The NSRR programme is in progress in JAERI using a pulsed reactor to evaluate the behavior of reactor fuels under reactivity accident conditions. This report describes briefly the experimental results and preliminary analysis of two cluster tests. In the cluster configuration of five fuel rods, the power distribution in outer fuel rods are not symmetric due to neutron absorption in central fuel rod. The cladding temperature on the exterior boundaries of the cluster is higher than that in interior. Good agreement was obtained between the calculated and measured cladding temperature histories. In the 3.8$ excess reactivity test, cluster averaged energy deposition of 237 cal/g.UO 2 , cladding melting and deformation were limited to the portions of the fuel rods that were on the exterior boundaries of the cluster. (auth.)

Tevatron physics results

CERN Multimedia

CERN. Geneva

2007-01-01

I will summarize the physics results from the Tevatron experiments with particular emphasis on the experimental methods used in different kinds of analysis. In particular, the Tevatron is a proton-antiproton collider that has now accumulated more than 2 fb^-1 of luminosity in the two experiments, called CDF and D0. In this lecture I will review the results on inclusive productions of jets, W- and Z-bosons, the results in the flavor sector, the measurements of top production, searches for Higgs boson production and searches for physics beyond the Standard Model. In each case I will explain the basic experimental concepts and methods needed for making the measurement.

CO2 Capture in Ionic Liquids: A Review of Solubilities and Experimental Methods

Directory of Open Access Journals (Sweden)

Elena Torralba-Calleja

2013-01-01

Full Text Available The growing concern of climate change and global warming has in turn given rise to a thriving research field dedicated to finding solutions. One particular area which has received considerable attention is the lowering of carbon dioxide emissions from large-scale sources, that is, fossil fuel power. This paper focuses on ionic liquids being used as novel media for CO2 capture. In particular, solubility data and experimental techniques are used at a laboratory scale. Cited CO2 absorption data for imidazolium-, pyrrolidinium-, pyridinium-, quaternary-ammonium-, and tetra-alkyl-phosphonium-based ionic liquids is reviewed, expressed as mole fractions (X of CO2 to ionic liquid. The following experimental techniques are featured: gravimetric analysis, the pressure drop method, and the view-cell method.

Armature reaction effects on a high temperature superconducting field winding of an synchronous machine: experimental results

DEFF Research Database (Denmark)

Mijatovic, Nenad; Jensen, Bogi Bech

2014-01-01

This paper presents experimental results from the Superwind laboratory setup. Particular focus in the paper has been placed on describing and quantifying the influence of armature reaction on performance of the HTS filed winding. Presented experimental results have confirmed the HTS field winding...

Technical Note: Experimental results from a prototype high-field inline MRI-linac

Energy Technology Data Exchange (ETDEWEB)

Liney, G. P., E-mail: gary.liney@sswahs.nsw.gov.au [Department of Medical Physics, Ingham Institute for Applied Medical Research, Liverpool NSW 2170 (Australia); Dong, B.; Zhang, K. [Department of Medical Physics, Ingham Institute for Applied Medical Research, Liverpool NSW 2170 (Australia); and others

2016-09-15

Purpose: The pursuit of real-time image guided radiotherapy using optimal tissue contrast has seen the development of several hybrid magnetic resonance imaging (MRI)-treatment systems, high field and low field, and inline and perpendicular configurations. As part of a new MRI-linac program, an MRI scanner was integrated with a linear accelerator to enable investigations of a coupled inline MRI-linac system. This work describes results from a prototype experimental system to demonstrate the feasibility of a high field inline MR-linac. Methods: The magnet is a 1.5 T MRI system (Sonata, Siemens Healthcare) was located in a purpose built radiofrequency (RF) cage enabling shielding from and close proximity to a linear accelerator with inline (and future perpendicular) orientation. A portable linear accelerator (Linatron, Varian) was installed together with a multileaf collimator (Millennium, Varian) to provide dynamic field collimation and the whole assembly built onto a stainless-steel rail system. A series of MRI-linac experiments was performed to investigate (1) image quality with beam on measured using a macropodine (kangaroo) ex vivo phantom; (2) the noise as a function of beam state measured using a 6-channel surface coil array; and (3) electron contamination effects measured using Gafchromic film and an electronic portal imaging device (EPID). Results: (1) Image quality was unaffected by the radiation beam with the macropodine phantom image with the beam on being almost identical to the image with the beam off. (2) Noise measured with a surface RF coil produced a 25% elevation of background intensity when the radiation beam was on. (3) Film and EPID measurements demonstrated electron focusing occurring along the centerline of the magnet axis. Conclusions: A proof-of-concept high-field MRI-linac has been built and experimentally characterized. This system has allowed us to establish the efficacy of a high field inline MRI-linac and study a number of the technical

Interpretation of PISCES -- A RF antenna system experimental results

International Nuclear Information System (INIS)

Rothweil, D.A.; Phelps, D.A.; Doerner, R.

1995-10-01

The paper describes experimental data from rf coupling experiments using one to four coil antenna arrays that encircle a linear magnetized plasma column. Experimental results using single turn coil that produce symmetric (i.e. m = 0), dipole (m = 1), and radial rf magnetic fields for coupling to ion waves are compared. By operating without a Faraday shield, it was observed for the first time that the plasma resistive load seen by these different antenna types tends to increase with the number of turns to at least the second power. A four-turn m = 0 coil experienced a record 3--5 Ω loading, corresponding to over 90% power coupling to the plasma. A four-turn m = 1 coil experienced up to 1--1.5 Ω loading, also higher than previous observations. First time observations using a two coil array of m = 0 coil are also reported. As predicted, the loading decreases with increasing phase between coil from 0 degree to 180 degree. Experiments using four coil arrays were difficult to optimize and interpret primarily due to complexity of the manual tuning. To facilitate this optimization in the future, a proposed feedback control system that automatically matches load variations between 0.2 and 10 Ω is described

Experimental and numerical results from hybrid retrofitted photovoltaic panels

International Nuclear Information System (INIS)

Rossi, Cecilia; Tagliafico, Luca A.; Scarpa, Federico; Bianco, Vincenzo

2013-01-01

Highlights: • The experimental study focuses on the feasibility of hybrid PV/T panels retrofitting. • The critical role of a thin layer of air between PV panel and back plate is evidenced. • The benefit of the addition of a conductive paste layer is analyzed via FEM simulations. • The use of wood ribs to stick the back plate represents a cheap effective solution. - Abstract: The aim of present study is to investigate different methodologies to achieve a better contact between a photovoltaic panel and a thermal plate, in order to cool the PV panel by means of water in the perspective of coupling it with a heat pump. It is believed that this kind of system allows to obtain a higher energy efficiency. The analysis is developed both experimentally and numerically, testing different kinds of configurations in different operating conditions. Simulations are employed to analyze the effect of the variations of the contact resistance between the panel and the thermal plates, demonstrating that the use of a conductive paste increases the overall performance of the panel. Results show interesting possibilities in terms of retrofitting of existing photovoltaic panels by employing very simple solutions, such as to fix the thermal plate on the rear of the panel by means of wood ribs

New experimental method for investigation of the nucleon polarizabilities

International Nuclear Information System (INIS)

Yevetska, O.; Watzlawik, S.; Ahrens, J.; Alkhazov, G.D.; Chizhov, V.P.; Maev, E.M.; Neumann-Cosel, P. von; Orischin, E.M.; Petrov, G.E.; Porte, J.-M.; Richter, A.; Sarantsev, V.V.; Schrieder, G.; Smirenin, Yu.V.

2010-01-01

At the continuous wave (cw) Superconducting Darmstadt Electron Linear Accelerator S-DALINAC, a new method has been developed for the determination of the electric (α-bar) and magnetic (β-bar) polarizabilities of the proton and the deuteron. For that purpose the energy and angular dependence of the differential cross-section for elastic γp and γd scattering of bremsstrahlung photons in the energy range between 20 and 100 MeV is measured by detecting the recoiling proton (deuteron) in coincidence with the scattered bremsstrahlung photon. α-bar and β-bar are then found by means of a best fit to a theoretical description of the scattering cross-section with these quantities as open parameters. The experimental setup consists of a bremsstrahlung photon facility, two specially designed high pressure hydrogen (deuterium) ionization chambers which serve as targets and detectors of the recoil proton (deuteron), NaI gamma spectrometers and several additional detectors for beam diagnostics and normalization. The whole setup was tested using bremsstrahlung photon beams with endpoint energies of 60 and 79.3 MeV. The results of the test experiments show that future high-statistics measurements are feasible.

Investigation on human serum albumin and Gum Tragacanth interactions using experimental and computational methods.

Science.gov (United States)

Moradi, Sajad; Taran, Mojtaba; Shahlaei, Mohsen

2018-02-01

The study on the interaction of human serum albumin and Gum Tragacanth, a biodegradable bio-polymer, has been undertaken. For this purpose, several experimental and computational methods were used. Investigation of thermodynamic parameters and mode of interactions were carried out using Fluorescence spectroscopy in 300 and 310K. Also, a Fourier transformed infrared spectra and synchronous fluorescence spectroscopy was performed. To give detailed insight of possible interactions, docking and molecular dynamic simulations were also applied. Results show that the interaction is based on hydrogen bonding and van der Waals forces. Structural analysis implies on no adverse change in protein conformation during binding of GT. Furthermore, computational methods confirm some evidence on secondary structure enhancement of protein as a presence of combining with Gum Tragacanth. Copyright © 2017 Elsevier B.V. All rights reserved.

Experimental and modelling results of a parallel-plate based active magnetic regenerator

DEFF Research Database (Denmark)

Tura, A.; Nielsen, Kaspar Kirstein; Rowe, A.

2012-01-01

The performance of a permanent magnet magnetic refrigerator (PMMR) using gadolinium parallel plates is described. The configuration and operating parameters are described in detail. Experimental results are compared to simulations using an established twodimensional model of an active magnetic...

Physical principles underlying the experimental methods for studying the orientational order of liquid crystals

International Nuclear Information System (INIS)

Limmer, S.

1989-01-01

The basic physical principles underlying different experimental methods frequently used for the determination of orientational order parameters of liquid crystals are reviewed. The methods that are dealt with here include the anisotropy of the diamagnetic susceptibility, birefringence, linear dichroism, Raman scattering, fluorescence depolarization, electron paramagnetic resonance (EPR), and nuclear magnetic resonance (NMR). The fundamental assertions that can be obtained by the different methods as well as their advantages, drawbacks and limitations are inspected. Typical sources of uncertainties and inaccuracies are discussed. To quantitatively evaluate the experimental data with reference to the orientational order the general tensor formalism developed by Schmiedel was employed throughout according to which the order matrix comprises 25 real elements yet. Within this context the interplay of orientational ordering and molecular conformation is scrutinized. (author)

Methods of experimental settlement of contradicting data in evaluated nuclear data libraries

Directory of Open Access Journals (Sweden)

V. A. Libman

2016-12-01

Full Text Available The latest versions of the evaluated nuclear data libraries (ENDLs have contradictions concerning data about neutron cross sections. To resolve this contradiction we propose the method of experimental verification. This method is based on using of the filtered neutron beams and following measurement of appropriate samples. The basic idea of the method is to modify the suited filtered neutron beam so that the differences between the neutron cross sections in accordance with different ENDLs become measurable. Demonstration of the method is given by the example of cerium, which according to the latest versions of four ENDLs has significantly different total neutron cross section.

Ultrasonic wave propagation through aberrating layers: experimental verification of the conjugate gradient Rayleigh method

NARCIS (Netherlands)

Ledoux, L.A.F.; Berkhoff, Arthur P.; Thijssen, J.M.

The Conjugate Gradient Rayleigh method for the calculation of acoustic reflection and transmission at a rough interface between two media was experimentally verified. The method is based on a continuous version of the conjugate gradient technique and plane-wave expansions. We measured the beam

Computer Class Role Playing Games, an innovative teaching methodology based on STEM and ICT: first experimental results

Science.gov (United States)

Maraffi, S.

2016-12-01

Context/PurposeWe experienced a new teaching and learning technology: a Computer Class Role Playing Game (RPG) to perform educational activity in classrooms through an interactive game. This approach is new, there are some experiences on educational games, but mainly individual and not class-based. Gaming all together in a class, with a single scope for the whole class, it enhances peer collaboration, cooperative problem solving and friendship. MethodsTo perform the research we experimented the games in several classes of different degrees, acquiring specific questionnaire by teachers and pupils. Results Experimental results were outstanding: RPG, our interactive activity, exceed by 50% the overall satisfaction compared to traditional lessons or Power Point supported teaching. InterpretationThe appreciation of RPG was in agreement with the class level outcome identified by the teacher after the experimentation. Our work experience get excellent feedbacks by teachers, in terms of efficacy of this new teaching methodology and of achieved results. Using new methodology more close to the student point of view improves the innovation and creative capacities of learners, and it support the new role of teacher as learners' "coach". ConclusionThis paper presents the first experimental results on the application of this new technology based on a Computer game which project on a wall in the class an adventure lived by the students. The plots of the actual adventures are designed for deeper learning of Science, Technology, Engineering, Mathematics (STEM) and Social Sciences & Humanities (SSH). The participation of the pupils it's based on the interaction with the game by the use of their own tablets or smartphones. The game is based on a mixed reality learning environment, giving the students the feel "to be IN the adventure".

Modern methods of experimental construction of texture complete direct pole figures by using X-ray data

Science.gov (United States)

Isaenkova, M.; Perlovich, Yu; Fesenko, V.

2016-04-01

Currently used methods for constructing texture complete direct pole figure (CDPF) based on the results of X-ray diffractometric measurements were considered with respect to the products of Zr-based alloys and, in particular, used in a nuclear reactor cladding tubes, for which the accuracy of determination of integral texture parameters is of the especial importance. The main attention was devoted to technical issues which are solved by means of computer processing of large arrays of obtained experimental data. Among considered questions there are amendments of the defocusing, techniques for constructing of complete direct pole figures and determination of integral textural parameters. The methods of reconstruction of complete direct pole figures by partial direct pole figures recorded up to tilt angles of sample ψ=70-80°: the method of extrapolation of data to an uninvestigated region of the stereographic projection, and the method of "sewing" of partial pole figures measured for three mutually perpendicular plane sections of the product. The limits of applicability of these methods, depending on the shape of the test product and the degree of inhomogeneity of the layer-by-layer texture, were revealed. On the basis of a large number of experimental data, the accuracy of the integral parameters used for calculation of the physical and mechanical properties of metals with a hexagonal crystal structure was found to be equal to 0.02, when taking into account the texture heterogeneity of regular products from Zr-based alloys.

Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results

Science.gov (United States)

Humada, Ali M.; Hojabri, Mojgan; Sulaiman, Mohd Herwan Bin; Hamada, Hussein M.; Ahmed, Mushtaq N.

2016-01-01

A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions. PMID:27035575

SPES-2, the full-height, full-pressure, test facility simulating the AP600 plant: Main results from the experimental campaign

International Nuclear Information System (INIS)

Medich, C.; Rigamonti, M.; Martinelli, R.; Tarantini, M.; Conway, L.

1995-01-01

The SPES-2 is a full height, full pressure experimental test facility reproducing the Westinghouse AP600 reactor with a scaling factor of 1/395. The experimental plant, designed and operated by SIET in Piacenza, consists of a full simulation of the AP600 primary core cooling system including all the passive and active safety systems. In 1992, Westinghouse, in cooperation with ENEL, ENEA, SIET and ANSALDO developed an experimental program to test the integrated behavior of the AP600 passive safety systems. The SPES-2 test matrix, concluded in November 1994, has examined the AP600 passive safety system response for a range of small break LOCAs at different locations on the primary system and on the passive system lines; single steam generator tube ruptures with both passive and active non-safety systems, and a main steam line break transient to demonstrate the capability of passive safety systems for rapid cooldown. Each of the tests has provided detailed experimental results for verification of the capability of the analysis methods to predict the integrated passive safety system behavior

Comparison of numerical results with experimental data for single-phase natural convection in an experimental sodium loop

International Nuclear Information System (INIS)

Ribando, R.J.

1979-01-01

A comparison is made between computed results and experimental data for single-phase natural convection in an experimental sodium loop. The tests were conducted in the Thermal-Hydraulic Out-of-Reactor Safety (THORS) Facility, an engineering-scale high temperature sodium facility at the Oak Ridge National Laboratory used for thermal-hydraulic testing of simulated LMFBR subassemblies at normal and off-normal operating conditions. Heat generation in the 19 pin assembly during these tests was typical of decay heat levels. Tests were conducted both with zero initial forced flow and with a small initial forced flow. The bypass line was closed in most tests, but open in one. The computer code used to analyze these tests [LONAC (LOw flow and NAtural Convection)] is an ORNL-developed, fast running, one-dimensional, single-phase finite difference model for simulating forced and free convection transients in the THORS loop

A review of experimental results obtained in Au-Au collisions at the RHIC-BNL energies using BRAHMS experimental set-up

International Nuclear Information System (INIS)

Jipa, Alexandru

2003-01-01

Ultrarelativistic heavy ion collisions are useful tools to investigate highly excited dense nuclear matter. At sufficiently high temperature, nuclear matter is expected to undergo a phase transition to quark-gluon plasma. Therefore, new experiments have been proposed to investigate the behaviour of the highly excited dense nuclear matter. One of the experiments performed at the Relativistic Heavy Ion Collider from Brookhaven National Laboratory is the BRAHMS Experiment. In the three running years many experimental data have been obtained. These data permitted to establish significant experimental results on charged pion, charged kaon, proton and antiproton production in Au-Au collisions at 130 A GeV and 200 A GeV in CMS. The present work summarizes the main experimental results on charged particle multiplicities, rapidity distributions, momentum spectra, antiparticle to particle ratios and connects these results with some interesting physical quantities. Their dependencies on the available energies in the CMS in similar collisions are included. Interesting behaviours with the increase of this energy are reported. The most interesting are related to the behaviour of the antiproton to proton ratio on the collision centrality and on the available energy in the centre of mass system, the strangeness production, Coulomb repulsion and slope parameters of the momentum spectra. A few new steps in the knowledge of the behaviour of the highly excited and dense nuclear matter can be reported. (authors)

THE MODERN TRENDS AND EXPERIMENTAL METHODS OF TRAINING FUTURE SPECIALISTS IN THE FIELD OF HISTRIONIC ART

Directory of Open Access Journals (Sweden)

Julia Sergeevna Skvortsova

2013-11-01

Full Text Available This article reflects the specific ways of training specialists in the sphere of histrionic art, contemporary trends and special scientific experiments in the education of actors.We consider the traditional aspects of histrionic art specialists’ occupational fitness and modern requirements upon actor’s psycho-physical training.There also follows historical parallels in studying actor’s energy in the researches of K. Stanislavsky, M. Chekhov, T. Reebo, W. James, A. Maneggetty as well as in the modern researches of L. Gracheva.And there was proved the reason for including some Yoga elements and Academician M.Norbecov’s exercises system into the actors training practice.In the article Yoga for actors considers as a system of emotional and physical preparation to the artistic creative work, as a method of self-control that let an actor be really deep in his creative condition.There also was described an advantageous result of applying at our experimental laboratory of actors Yoga classes some exercises that reveal connection of person’s carriage and his condition in the process of working on the outward demonstration of this or that emotion in order to create appropriate inner state.Object: Studying the influence on the productivity of actors’ professional education of the Yoga elements included into the actors’ psycho-technique practice training.Methods: theoretical, experimental and observational methods of research.Results: After using these methods during the classes the rate of student’s psycho-physical APPARATUS has extremely increased.The area of application: the educational process at artistic creative high schools.DOI: http://dx.doi.org/10.12731/2218-7405-2013-7-52

Experimental results for characterization of a tapered plastic optical fiber sensor based on SPR

Science.gov (United States)

Cennamo, N.; Galatus, R.; Zeni, L.

2015-05-01

The experimental results obtained with two different Plastic Optical Fiber (POF) geometries, tapered and not-tapered, for a sensor based on Surface Plasmon Resonance (SPR) are presented. SPR is used for determining the refractive index variations at the interface between a gold layer and a dielectric medium (aqueous medium). In this work SPR sensors in POF configurations, useful for bio-sensing applications, have been realized for the optimization of the sensitivity and experimentally tested. The results show as the sensitivity increases with the tapered POF configuration, when the refractive index of aqueous medium increases.

Experimental Methods Related to Coupled Fast-Thermal Systems at the RB Reactor

International Nuclear Information System (INIS)

Pesic, M.

2002-01-01

In addition to the review of RB reactor characteristics this presentation is focused on the coupled fast-thermal systems achieved at the reactor. The following experimental methods are presented: neutron spectra measurements; steady state experiments and kinetic measurements ( β eff ) related to the coupled fast-thermal cores

Experimental validation of the intrinsic spatial efficiency method over a wide range of sizes for cylindrical sources

Energy Technology Data Exchange (ETDEWEB)

Ortiz-Ramŕez, Pablo, E-mail: rapeitor@ug.uchile.cl; Larroquette, Philippe [Departamento de Física, Facultad de Ciencias, Universidad de Chile (Chile); Camilla, S. [Departamento de Física, Universidad Tecnológica Metropolitana (Chile)

2016-07-07

The intrinsic spatial efficiency method is a new absolute method to determine the efficiency of a gamma spectroscopy system for any extended source. In the original work the method was experimentally demonstrated and validated for homogeneous cylindrical sources containing {sup 137}Cs, whose sizes varied over a small range (29.5 mm radius and 15.0 to 25.9 mm height). In this work we present an extension of the validation over a wide range of sizes. The dimensions of the cylindrical sources vary between 10 to 40 mm height and 8 to 30 mm radius. The cylindrical sources were prepared using the reference material IAEA-372, which had a specific activity of 11320 Bq/kg at july 2006. The obtained results were better for the sources with 29 mm radius showing relative bias lesser than 5% and for the sources with 10 mm height showing relative bias lesser than 6%. In comparison with the obtained results in the work where we present the method, the majority of these results show an excellent agreement.

Experimental results of passive vibro-acoustic leak detection in SFR steam generator mock-up

International Nuclear Information System (INIS)

Moriot, J.; Gastaldi, O.; Maxit, L.; Guyader, J-L.; Perisse, J.; Migot, B.

2013-06-01

Regarding to GEN 4 context, it is necessary to fulfil the high safety standards for sodium fast reactors (SFR), particularly against water-sodium reaction which may occur in the steam generator units (SGU) in case of leak. This reaction can cause severe damages in the component in a short time. Detecting such a leak by visual in-sodium inspection is impossible because of sodium opacity. Hydrogen detection is then used but the time response of this method can be high in certain operating conditions. Active and passive acoustic leak detection methods were studied before SUPERPHENIX plant shutdown in 1997 to detect a water-into-sodium leak with a short time response. In the context of the new R and D studies for SFR, an innovative passive vibro-acoustic method is developed in the framework of a Ph.D. thesis to match with GEN 4 safety requirements. The method consists in assuming that a small leak emits spherical acoustic waves in a broadband frequency domain, which propagate in the liquid sodium and excite the SGU cylindrical shell. These spatially coherent waves are supposed to be buried by a spatially incoherent background noise. The radial velocities of the shell is measured by an array of accelerometers positioned on the external envelop of the SGU and a beam forming treatment is applied to increase the signal-to-noise ratio (SNR) and to detect and localize the acoustic source. Previous numerical experiments were achieved and promising results were obtained. In this paper, experimental results of the proposed passive vibro-acoustic leak detection are presented. The experiment consists in a cylindrical water-filled steel pipe representing a model of SGU shell without tube bundle. A hydro-phone emitting an acoustic signal is used to simulate an acoustic monopole. Spatially uncorrelated noise or water-flow induced shell vibrations are considered as the background noise. The beam-forming method is applied to vibration signals measured by a linear array of

Data base of reactor physics experimental results in Kyoto University critical assembly experimental facilities

International Nuclear Information System (INIS)

Ichihara, Chihiro; Fujine, Shigenori; Hayashi, Masatoshi

1986-01-01

The Kyoto University critical assembly experimental facilities belong to the Kyoto University Research Reactor Institute, and are the versatile critical assembly constructed for experimentally studying reactor physics and reactor engineering. The facilities are those for common utilization by universities in whole Japan. During more than ten years since the initial criticality in 1974, various experiments on reactor physics and reactor engineering have been carried out using many experimental facilities such as two solidmoderated cores, a light water-moderated core and a neutron generator. The kinds of the experiment carried out were diverse, and to find out the required data from them is very troublesome, accordingly it has become necessary to make a data base which can be processed by a computer with the data accumulated during the past more than ten years. The outline of the data base, the data base CAEX using personal computers, the data base supported by a large computer and so on are reported. (Kako, I.)

Note: Comparison experimental results of the laser heterodyne interferometer for angle measurement based on the Faraday effect

Science.gov (United States)

Zhang, Enzheng; Chen, Benyong; Zheng, Hao; Teng, Xueying; Yan, Liping

2018-04-01

A laser heterodyne interferometer for angle measurement based on the Faraday effect is proposed. A novel optical configuration, designed by using the orthogonal return method for a linearly polarized beam based on the Faraday effect, guarantees that the measurement beam can return effectively even though an angular reflector has a large lateral displacement movement. The optical configuration and measurement principle are presented in detail. Two verification experiments were performed; the experimental results show that the proposed interferometer can achieve a large lateral displacement tolerance of 7.4 mm and also can realize high precision angle measurement with a large measurement range.

Critical experiments carried out with a homogeneous plutonium solution. Experimental results. Theoretical interpretations

International Nuclear Information System (INIS)

Bouly, J.C.; Caizergues, R.; Deilgat, E.; Houelle, M.; Lecorche, P.

1967-01-01

This report groups together a series of experimental and theoretical studies on cylinders and plates of solution tried out at the Valduc Centre. a) Comparison of the theoretical and experimental results obtained on critical heights of solutions. b) Study of the effect of nitrogen, introduced in the form of the ion NO 3- , on the reactivity of fissile media. c) Study of the effect of 240 94 Pu on the reactivity of these media. d) Study of the influence of the dimensions of the inner cavity of annular cylinders, as well as of the influence of the moderator which may be introduced. Simple results were obtained which were easy to apply. An extrapolation to other geometries is made. (authors) [fr

Estimation of the drift eliminator efficiency using numerical and experimental methods

Directory of Open Access Journals (Sweden)

Stodůlka Jiří

2016-01-01

Full Text Available The purpose of the drift eliminators is to prevent water from escaping in significant amounts the cooling tower. They are designed to catch the droplets dragged by the tower draft and the efficiency given by the shape of the eliminator is the main evaluation criteria. The ability to eliminate the escaping water droplets is studied using CFD and using the experimental IPI method.

Application of experimental plans method to formulate a self compacting cement paste

Directory of Open Access Journals (Sweden)

Mebrouki, A.

2010-06-01

Full Text Available The self-compacting concrete formulation means to elaborate a self-compacting cement paste to which will be injected aggregates. The purpose of this work is to find the composition of this cement paste containing local materials (pozzolanic cement, limestone fillers, superplasticizer and water having self-compacting properties. The use of the experimental plans method shows that it is possible to delimit an experimental field bounded by the volumetric proportions of materials composing the paste. The field was transformed in equations form conditioned by implicit constraints, defining zones of minimal shearing threshold and maximum viscosity; numerical resolution submitted to the optimization criteria permitted to define the volumetric proportions of each mixing parameter contributing to the preparation of an optimal paste. After experimental checking to validate obtained results, conclusions are that, from results given by ternary diagrams and desirability’s functions, a composition of an optimal self-compacting cement pas was obtained.

En este trabajo se estudia la constitución de una pasta autocompactante a base de materiales locales argelinos (cemento binario de base puzolánica natural de Beni Saf y filler calizo de cantera. La reología de la pasta se estudia en función de las dosificaciones de cemento, caliza, superplastificante y agua. La fluidez de las pastas así formadas se deducen de los ensayos de escurrimiento del mini cono y del tiempo de flujo en el cono de Marsh. Utilizando el diseño estadístico de mezclas, el número de ensayos se ha visto considerablemente reducido, el problema se transformó en ecuaciones y después se resolvió numéricamente. A partir de las curvas de los diagramas ternarios, uniendo las respuestas de escurrimiento y el tiempo de flujo de las pastas en función de las dosificaciones en constituyentes y estudiando las funciones de conveniencia para cada respuesta, se terminará por deducir una

Experimental Learning in Nursing Literature Education

Directory of Open Access Journals (Sweden)

Eskandar Fathiazar

2015-08-01

Full Text Available ​Experimental learning is a type of discovery learning. This method of learning appears to be suitable for nursing education, but there is not enough evidence about it. As a result, in this non-systematic review article, after explaining experimental learning, its application in nursing will be presented based on literature review and with functional examples. According to the results, in this kind of learning, students practice with experimental cases and learn by failure in. Participants should have the main role and teachers act as mentors or learning facilitators. According to the literature, it seems useful to use this new method in nursing education.

Solubility of water in fluorocarbons: Experimental and COSMO-RS prediction results

International Nuclear Information System (INIS)

Freire, Mara G.; Carvalho, Pedro J.; Santos, Luis M.N.B.F.; Gomes, Ligia R.; Marrucho, Isabel M.; Coutinho, Joao A.P.

2010-01-01

This work aims at providing experimental and theoretical information about the water-perfluorocarbon molecular interactions. For that purpose, experimental solubility results for water in cyclic and aromatic perfluorocarbons (PFCs), over the temperature range between (288.15 and 318.15) K, and at atmospheric pressure, were obtained and are presented. From the experimental solubility dependence on temperature, the partial molar solution and solvation thermodynamic functions such as Gibbs free energy, enthalpy and entropy were determined and are discussed. The process of dissolution of water in PFCs is shown to be spontaneous for cyclic and aromatic compounds. It is demonstrated that the interactions between the non-aromatic PFCs and water are negligible while those between aromatic PFCs and water are favourable. The COSMO-RS predictive capability was explored for the description of the water solubility in PFCs and others substituted fluorocompounds. The COSMO-RS is shown to be a useful model to provide reasonable predictions of the solubility values, as well as to describe their temperature and structural modifications dependence. Moreover, the molar Gibbs free energy and molar enthalpy of solution of water are predicted remarkably well by COSMO-RS while the main deviations appear for the prediction of the molar entropy of solution.

Concepts to optimize stent-grafting of abdominal aortic aneurysms based on results of experimental studies

International Nuclear Information System (INIS)

Chavan, A.; Kirchhoff, T.; Baus, S.; Galanski, M.; Pichlmaier, M.

2001-01-01

Purpose. In the endoluminal therapy of abdominal aortic aneurysms, a short proximal aneurysm neck, endoleaks and the large size and stiffness of the introducer systems are responsible for many of the complications and sub-optimal outcomes. The purpose of the present review article is to to suggest strategies to minimize these complications based on the results of experimental studies in animals. Material and methods. After implanting various types of stents across the renal artery origins, the functional and morphological changes in the kidneys and renal vessels were studied by various authors. In order to prevent progressive widening of the proximal aneurysmal neck and graft dislocation, Sonesson et al. performed a laparoscopic banding around the proximal neck in pigs. To study the effects of endoleaks, Marty, Schurink and Pitton carried out pressure measurements in experimental aneurysms with and without endoleaks. Sakaguchi and Pavcnik developed the 'Twin-tube endografts' (TTEG) and the 'Bifurcated drum occluder endografts' (BDOEG) and tested them in dogs. Results. Up to 3 months after suprarenal stent placement, Chavan et al. detected no significant fall in the mean inulin clearance in sheep (140±46 ml/min before, 137±58 ml/min after). Nasim et al. and Malina et al. reported similar observations with respect to renal function. Suprarenal fixation may result in isolated thrombotic occlusions of the renal arteries and microinfarcts in the kidneys. Mean aortic diameters at the level of banding were significantly smaller in the animals with aortic banding as opposed to those in the control group without banding (8 mm vs 11 mm, p=0.004). The banding caused a secure proximal fixation of the stent-graft. Persistent endoleaks resulted in significantly higher intraaneurysmal pressures. Although the TTEG and the BDOEG stent-grafts required smaller sheaths, occlusions were observed in 8% (TTEG) and 60% (BDOEG) of the graft limbs. (orig.) [de

An Experimental Test of a Biodynamic Method of Weed Suppression: The Biodynamic Seed Peppers

Directory of Open Access Journals (Sweden)

Bruce Kenneth Kirchoff

2016-04-01

Full Text Available An experimental test of a biodynamic agriculture method of weed suppression was carried out in growth chambers to establish the feasibility of the method as a preliminary to field trials. Four generations of Brassica rapa plants were used in a randomized block design. Treated flats received ashed seeds prepared according to biodynamic indications. Seed weight and counts were measured at the end of each generation, and germination of the control and experimental seed was investigated at the end of generation four. The biodynamic seed peppers, created and applied as described here, had no effect on seed production or viability, and did not effectively inhibit reproduction of the targeted species over the course of four consecutive treatments.

Removal of arsenic from wastewaters by cryptocrystalline magnesite: complimenting experimental results with modelling

CSIR Research Space (South Africa)

Masindi, Vhahangwele

2016-02-01

Full Text Available -1 Journal of Cleaner Production Removal of arsenic from wastewaters by cryptocrystalline magnesite: complimenting experimental results with modelling Vhahangwele Masindi W. Mugera Gitari Keywords: Arsenic Mine leachates Cryptocrystalline...

FIRST EXPERIMENTAL RESULTS FROM DEGAS, THE QUANTUM LIMITED BRIGHTNESS ELECTRON SOURCE

International Nuclear Information System (INIS)

Zolotorev, Max S.; Commins, Eugene D.; Oneill, James; Sannibale, Fernando; Tremsin, Anton; Wan, Weishi

2008-01-01

The construction of DEGAS (DEGenerate Advanced Source), a proof of principle for a quantum limited brightness electron source, has been completed at the Lawrence Berkeley National Laboratory. The commissioning and the characterization of this source, designed to generate coherent single electron 'bunches' with brightness approaching the quantum limit at a repetition rate of few MHz, has been started. In this paper the first experimental results are described

Control strategy and experimental study on a novel defrosting method for air-source heat pump

International Nuclear Information System (INIS)

Liang Caihua; Zhang Xiaosong; Li Xiuwei; Chen Zhenqian

2010-01-01

A new defrosting method - the sensible heat defrosting method, aiming at shelving the various disadvantages of the conventional reverse cycle defrosting was proposed in this paper. The mechanism and process of this method was analysed. To guarantee the reliability, the self-organizing control algorithm with self-learning function was introduced based on the cardinal fuzzy control algorithm. Moreover, the control strategy was enacted; the corresponding self-organizing fuzzy control system was developed; the Micro Controller Unit (MCU) based control unit was accomplished; and the experimental study was conducted to investigate the sample machine of air-source heat pump system. The results of the experiments showed that the self-organizing control algorithm has good control characteristic and effect. On one hand, the adverse shock from the conventional reverse cycle defrosting to the refrigeration system could be avoided through this proposed method; on the other hand, the 'oil rush' could also be eliminated. Besides, the thermal comfort could be greatly improved since the temperature fluctuation range of the supplied water is narrowed by applying this new method in practice.

Experimental investigation of CO_2 separation by adsorption methods in natural gas purification

International Nuclear Information System (INIS)

Chen, S.J.; Fu, Y.; Huang, Y.X.; Tao, Z.C.; Zhu, M.

2016-01-01

Highlights: • The ideal swing adsorption tank can improve the adsorption performance. • Pure CO_2 adsorption experimental data agrees well with extended Langmuir model. • Langmuir-Freundlich model correlates CO_2/CH_4 mixture adsorption data fairly well. • The temperature increases in the order swing 2 > swing1 > static for pure CO_2 adsorption. • Swinging the adsorption tank can improve the separation efficiency. - Abstract: CO_2 separation for natural gas purification by the adsorption method was studied in detail using volumetric adsorption apparatus. The crystalline phase and microstructure of the experimental sample were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Micromeritics ASAP 2020 instrument. The XRD pattern proves that the experimental sample consists of 13X zeolites. The SEM images show that the 13X zeolites expose a large number of micro-channels on the surface of the particles. The microporous volume is 0.22 cm"3 (STP)/g. The ideal swing frequency for the adsorption tank can improve the adsorption performance of an adsorbent compared with a static adsorption tank. The pure CO_2 adsorption experimental data agrees well with the extended Langmuir model. The Langmuir-Freundlich model correlates the CO_2/CH_4 mixture adsorption experimental data fairly well. The relative errors between the simulated results and the experimental data are very little, which indicates that these fitted models are correct. The average selectivity of CO_2/CH_4 in a static and swing adsorption tank are, respectively, 3.57 and 3.93, considerably higher than 1, indicating preferential CO_2 adsorption over CH_4 in CO_2/CH_4 mixtures. This also shows that the swing can improve CO_2 separation for natural gas purification. For the three types of motion status, the temperature of the adsorption tank increased in the order swing 2 > swing1 > static state for pure CO_2 adsorption in 13X zeolites. The temperature variation decreased as the

Isolated Liver Perfusion Using Percutaneous Methods:[ql An Experimental Study in the Pig

International Nuclear Information System (INIS)

Harnek, Jan; Cwikiel, Wojciech; Bergqvist, Lennart; Persson, Bo; Stridbeck, Hans

1996-01-01

Purpose: To develop a method for isolated perfusion of the liver using radiological methods. Methods: Twenty-one pigs, weighing about 20 kg, were divided into three groups. By transjugular and transfemoral approaches two occlusion balloons were placed in the inferior vena cava cranial and caudal, respectively, to the origin of the hepatic veins. One occlusion balloon was placed transfemorally in the common hepatic artery. Another occlusion balloon was inserted in the main branch of the portal vein via the transjugular-transhepatic approach in 11 pigs (groups 1 and 2), and in 10 pigs (group 3) by a percutaneous transhepatic route. After inflation of the balloons, patency of the isolated liver circulation was evaluated by recirculation of 99 Tc m -labelled human albumin during 30 min. Blood tests were obtained after 1, 3, 5, 10, 15, and 30 min to evaluate leakage from the liver to the systemic circulation. Results: Increasing leakage to the systemic circulation from the isolated liver circulation was observed in groups 1 and 2. In the third group the leakage was less than 10%. Conclusion: In an experimental animal model, isolated perfusion of the liver with minor leakage to the systemic circulation may be achieved using radiological methods

Experimental results of two stage harmonic generation with picosecond pulses on the Stanford Mark III FEL

International Nuclear Information System (INIS)

Hooper, B.A.; Utah Univ., Salt Lake City; Stanford Univ., CA; Benson, S.V.; Madey, M.J.; Cutolo, A.; Naples Univ.

1988-01-01

We report experimental results on upper harmonic conversion using a lithium niobate and a beta barium borate crystal to quadruple the FEL light up into the visible and near infrared. The effects of finite linewidth, birefringent walk-off, and group velocity walk-off on conversion efficiency will be discussed with reference to the experimental results. (orig.)

Simulation and preliminary experimental results for an active neutron counter using a neutron generator for a fissile material accounting

International Nuclear Information System (INIS)

Ahn, Seong-Kyu; Lee, Tae-Hoon; Shin, Hee-Sung; Kim, Ho-Dong

2009-01-01

An active neutron coincidence counter using a neutron generator as an interrogation source has been suggested. Because of the high energy of the interrogation neutron source, 2.5 MeV, the induced fission rate is strongly affected by the moderator design. MCNPX simulation has been performed to evaluate the performance achieved with these moderators. The side- and bottom-moderator are significantly important to thermalize neutrons to induce fission. Based on the simulation results, the moderators are designed to be adapted to the experimental system. Their preliminary performance has been tested by using natural uranium oxide powder samples. For a sample of up to 3.5 kg, which contains 21.7 g of 235 U, 2.64 cps/g- 235 U coincidence events have been measured. Mean background error was 9.57 cps and the resultant coincidence error was 13.8 cps. The experimental result shows the current status of an active counting using a neutron generator which still has some challenges to overcome. However, the controllability of an interrogation source makes this system more applicable for a variety of combinations with other non-destructive methods like a passive coincidence counting especially under a harsh environment such as a hot cell. More precise experimental setup and tests with higher enriched samples will be followed to develop a system to apply it to an active measurement for the safeguards of a spent fuel treatment process.

The Experimental Stand for Research of Wakefield Method of Charged Particles Acceleration

International Nuclear Information System (INIS)

Kiselev, V.A.; Linnik, A.F.; Onishchenko, I.N.; Onishchenko, N.I.; Sotnikov, G.V.; Uskov, V.V.

2006-01-01

The experimental installation and diagnostic equipment with motivation to use for various researches of wakefield method of charged particles acceleration both in plasma and in dielectric structure has been described. The main parameters of a sequence of short relativistic electron bunch and values of physical characteristics of slow-down structures have been presented

Internal wave emission from baroclinic jets: experimental results

Science.gov (United States)

Borcia, Ion D.; Rodda, Costanza; Harlander, Uwe

2016-04-01

Large-scale balanced flows can spontaneously radiate meso-scale inertia-gravity waves (IGWs) and are thus in fact unbalanced. While flow-dependent parameterizations for the radiation of IGWs from orographic and convective sources do exist, the situation is less developed for spontaneously emitted IGWs. Observations identify increased IGW activity in the vicinity of jet exit regions. A direct interpretation of those based on geostrophic adjustment might be tempting. However, directly applying this concept to the parameterization of spontaneous imbalance is difficult since the dynamics itself is continuously re-establishing an unbalanced flow which then sheds imbalances by GW radiation. Examining spontaneous IGW emission in the atmosphere and validating parameterization schemes confronts the scientist with particular challenges. Due to its extreme complexity, GW emission will always be embedded in the interaction of a multitude of interdependent processes, many of which are hardly detectable from analysis or campaign data. The benefits of repeated and more detailed measurements, while representing the only source of information about the real atmosphere, are limited by the non-repeatability of an atmospheric situation. The same event never occurs twice. This argues for complementary laboratory experiments, which can provide a more focused dialogue between experiment and theory. Indeed, life cycles are also examined in rotating-annulus laboratory experiments. Thus, these experiments might form a useful empirical benchmark for theoretical and modeling work that is also independent of any sort of subgrid model. In addition, the more direct correspondence between experimental and model data and the data reproducibility makes lab experiments a powerful testbed for parameterizations. Here we show first results from a small rotating annulus experiments and we will further present our new experimental facility to study wave emission from jets and fronts.

Optimization Design Method and Experimental Validation of a Solar PVT Cogeneration System Based on Building Energy Demand

Directory of Open Access Journals (Sweden)

Chao Zhou

2017-08-01

Full Text Available Photovoltaic-thermal (PVT technology refers to the integration of a photovoltaic (PV and a conventional solar thermal collector, representing the deep exploitation and utilization of solar energy. In this paper, we evaluate the performance of a solar PVT cogeneration system based on specific building energy demand using theoretical modeling and experimental study. Through calculation and simulation, the dynamic heating load and electricity load is obtained as the basis of the system design. An analytical expression for the connection of PVT collector array is derived by using basic energy balance equations and thermal models. Based on analytical results, an optimized design method was carried out for the system. In addition, the fuzzy control method of frequency conversion circulating water pumps and pipeline switching by electromagnetic valves is introduced in this paper to maintain the system at an optimal working point. Meanwhile, an experimental setup is established, which includes 36 PVT collectors with every 6 PVT collectors connected in series. The thermal energy generation, thermal efficiency, power generation and photovoltaic efficiency have been given in this paper. The results demonstrate that the demonstration solar PVT cogeneration system can meet the building energy demand in the daytime in the heating season.

Internal stress distribution of X-ring using photoelastic experimental hybrid method

Energy Technology Data Exchange (ETDEWEB)

Bernard, Alunda Ouma [Dedan Kimathi University of Technology, Nyeri (Kenya); Hawong, Jai Sug; Lim, Hyun Seok [Yeungnam University, Gyeongsan (Korea, Republic of); Shin, Dong Chul [Koje College, Geoje (Korea, Republic of)

2014-05-15

Sealing elements are essential parts of many machines, and are used to prevent the loss of a fluid or gas. When such fluids are not properly sealed, catastrophic failures may result. Many different types of rings have been developed to suit various industrial needs. Considerable research has been done on the O-ring. We analyze the internal stresses developed in an X-ring under a uniform squeeze rate of 20%, which is suitable for static applications, using a photoelastic experimental hybrid method. The internal pressures applied were 0.98, 1.96, 2.94, 3.92, 4.90, and 5.88 MPa. We show that sealing rings with X geometry have considerably higher internal stresses than O-ring seals. In addition, we demonstrate that after extrusion, for an internal pressure of 5.88 MPa, the two lobes on the upper contact surface merge, thereby increasing the contact length of the upper side significantly. Extrusion in the X-ring occurred when the internal pressure was 4.90 MPa.

Test of the core design methods for the THTR 300 with experimental results from the critical facility KAHTER

Energy Technology Data Exchange (ETDEWEB)

Hofmann, K.; Huebner, A.; Brandes, S.; Krings, F.

1974-10-15

At the Kernforschungsanlage Juelich, core physics experiments with core 1 and core 2 of the critical facility for high temperature reactors KAHTER were carried out in 1973. Core 2 corresponds to the THTR initial core in its moderation ratio S = 7500. Selected experimental results on the critical mass, on control rod worths, and reaction rate distributions were used for testing the most important procedures for the THTR core physics design. The zero-dimensional spectrum program MUPO with its cross section library and the and neutron flux calculations in two-dimensional diffusion approximation by CRAM are of central importance. It proved to be important to introduce modifications specific to the KAHTER plant into the standard models. Thus the void effect (void above the pebble bed) was investigated with DOT-2 by transport theory and a correction was introduced for the critical masses calculated by diffusion theory. Another feature already contained in the standard procedure, the increase of the diffusion constants for the hollow spaces between the spheres, results in a correction of 3.8% < delta-k for KAHTER, whereas in the THTR 300 it only amounts to several tenths % delta-k. Critical masses are predicted with accuracies of < 1.5 % or with regard to reactivity < 0.65 % delta-k. The calculated values for the radial neutron flux distributions deviate from the measured values in the core area by approximately lo %. In the case of the axial profiles, deviations are observed at the pebble bed surface which can be explained by the upper void, which cannot be satisfactorily represented by the diffusion theory. Control rod worths are predicted quite well, i.e., to within +/- 5%. An exception is the bank of 4 reflector rods, where the applied model of the "grey curtain" is not accurate because of the large distances between rods. The calculated control rod worths for that case were found to be too low, which does, however, not result in a safety problem.

Experimental investigation of radiation effect on human thermal comfort by Taguchi method

International Nuclear Information System (INIS)

Arslanoglu, Nurullah; Yigit, Abdulvahap

2016-01-01

Highlights: • Radiation heat flux from lighting lamps on human thermal comfort is studied. • The effect of posture position on thermal comfort is investigated. • The effect of clothing color on thermal comfort is examined. • Radiation heat flux from halogen reflector lamp increase skin temperature more. • Posture position effect on thermal comfort is less than the other parameters. - Abstract: In this study, the effect of radiation heat flux of lighting lamps on human thermal comfort was investigated by using Taguchi method. In addition, at indoor conditions, clothing color and posture position under the radiation effect on thermal comfort were also investigated. For this purpose, experiments were performed in an air conditioned laboratory room in summer and autumn seasons. The amount of temperature rise on the back was considered as performance parameter. An L8 orthogonal array was selected as an experimental plan for the third parameters mentioned above for summer and autumn seasons. The results were analyzed for the optimum conditions using signal-to-noise (S/N) ratio and ANOVA method. The optimum results were found to be clear halogen lamp as lighting lamp, white as t-shirt color, standing as posture position, in summer season. The optimum levels of the lighting lamp, t-shirt color and posture position were found to be clear halogen lamp, white, sitting in autumn season, respectively.

Search for muonium to antimuonium conversion: Overview and recent experimental results

International Nuclear Information System (INIS)

Reiner Schaefer, H.

1988-01-01

The motivation for an experimental search for muonium to antimuonium conversion is briefly discussed. Results of measurements on limits for the strength of the coupling constant involved in this interaction are summarized with emphasis on the recently completed search, LAMPF E985. Plans are presented for an upcoming next generation experiment, LAMF E1073, which aims at an improvement in the sensitivity by more than two orders of magnitude

Summary on experimental methods for statistical transient analysis of two-phase gas-liquid flow

International Nuclear Information System (INIS)

Delhaye, J.M.; Jones, O.C. Jr.

1976-06-01

Much work has been done in the study of two-phase gas-liquid flows. Although it has been recognized superficially that such flows are not homogeneous in general, little attention has been paid to the inherent discreteness of the two-phase systems. Only relatively recently have fluctuating characteristics of two-phase flows been studied in detail. As a result, new experimental devices and techniques have been developed for use in measuring quantities previously ignored. This report reviews and summarizes most of these methods in an effort to emphasize the importance of the fluctuating nature of these flows and as a guide to further research in this field

Dimethyl Ether: New Advances in Wear Testing: Theoretical and Experimental Results

DEFF Research Database (Denmark)

Sivebæk, Ion Marius; Sorenson, Spencer C; Jakobsen, J.

2003-01-01

The issues addressed in this paper are investigation of the wear mechanisms present in the standard lubricity test for diesel oil: The High frequency reciprocating Rig (HFRR). The HFRR is a laboratory wear test using a ball on disk configuration. The result of a test is the wear scar diameter (WSD...... surfaces with long-range elasticity. This last property has enabled the model to correlate well with experimental results. The outcome of the alkane calculations indicates that the longer ones lubricate better than the shorts ones but not necessarily because of viscosity differences. The reason is more...

Bootstrap resampling: a powerful method of assessing confidence intervals for doses from experimental data

International Nuclear Information System (INIS)

Iwi, G.; Millard, R.K.; Palmer, A.M.; Preece, A.W.; Saunders, M.

1999-01-01

Bootstrap resampling provides a versatile and reliable statistical method for estimating the accuracy of quantities which are calculated from experimental data. It is an empirically based method, in which large numbers of simulated datasets are generated by computer from existing measurements, so that approximate confidence intervals of the derived quantities may be obtained by direct numerical evaluation. A simple introduction to the method is given via a detailed example of estimating 95% confidence intervals for cumulated activity in the thyroid following injection of 99m Tc-sodium pertechnetate using activity-time data from 23 subjects. The application of the approach to estimating confidence limits for the self-dose to the kidney following injection of 99m Tc-DTPA organ imaging agent based on uptake data from 19 subjects is also illustrated. Results are then given for estimates of doses to the foetus following administration of 99m Tc-sodium pertechnetate for clinical reasons during pregnancy, averaged over 25 subjects. The bootstrap method is well suited for applications in radiation dosimetry including uncertainty, reliability and sensitivity analysis of dose coefficients in biokinetic models, but it can also be applied in a wide range of other biomedical situations. (author)

Validation of thermohydraulic codes by comparison of experimental results with computer simulations

International Nuclear Information System (INIS)

Madeira, A.A.; Galetti, M.R.S.; Pontedeiro, A.C.

1989-01-01

The results obtained by simulation of three cases from CANON depressurization experience, using the TRAC-PF1 computer code, version 7.6, implanted in the VAX-11/750 computer of Brazilian CNEN, are presented. The CANON experience was chosen as first standard problem in thermo-hydraulic to be discussed at ENFIR for comparing results from different computer codes with results obtained experimentally. The ability of TRAC-PF1 code to prevent the depressurization phase of a loss of primary collant accident in pressurized water reactors is evaluated. (M.C.K.) [pt

Ansiedade experimental humana Human experimental anxiety

Directory of Open Access Journals (Sweden)

Frederico Guilherme Graeff

2007-01-01

Full Text Available CONTEXTO: A ansiedade experimental no ser humano constitui-se em ponte entre os modelos animais e os ensaios clínicos. OBJETIVO: Este artigo focaliza métodos químicos e psicológicos utilizados para provocar ansiedade experimental em seres humanos. MÉTODOS: Realizou-se revisão seletiva da literatura. RESULTADOS: Os desafios farmacológicos têm sido usados principalmente para induzir ataques de pânico em pacientes com transtorno de pânico, os quais são mais sensíveis a eles que indivíduos normais ou pacientes portadores de outros transtornos psiquiátricos. Uma das mais importantes contribuições deste método é a de ter mostrado que os agentes panicogênicos mais seletivos, como o lactato ou a inalação de CO2, não ativam o eixo hormonal do estresse. Entre os métodos psicológicos, destacam-se o condicionamento de respostas elétricas da condutância da pele, cujo perfil farmacológico se aproxima daquele do transtorno de ansiedade generalizada, e o teste da simulação do falar em público, cuja farmacologia é semelhante à do transtorno de pânico. CONCLUSÕES: Tais resultados salientam a diferença entre a neurobiologia da ansiedade e a do pânico.BACKGROUND: Human experimental anxiety methods bridge the gap between animal models and clinical assays. OBJECTIVE: This article is focused on chemical and psychological procedures used to generate experimental anxiety in human beings. METHODS: A selective review of the literature has been carried out. RESULTS: Pharmacological challenges have been mainly used to induce panic attacks in panic disorder patients, who are more susceptible than normal individuals or patients with other psychiatric disorders. One of the most important contributions of this method is to have shown that the most selective panicogenic agents, such as lactate or CO2 inhalation, do not activate the hormonal stress axis. Among the psychological methods stand the conditioning of the electrical skin conductance

Tilted wheel satellite attitude control with air-bearing table experimental results

Science.gov (United States)

Inumoh, Lawrence O.; Forshaw, Jason L.; Horri, Nadjim M.

2015-12-01

Gyroscopic actuators for satellite control have attracted significant research interest over the years, but their viability for the control of small satellites has only recently started to become clear. Research on variable speed gyroscopic actuators has long been focused on single gimbal actuators; double gimbal actuators typically operate at constant wheel spin rate and allow tilt angle ranges far larger than the ranges needed to operate most satellite missions. This research examines a tilted wheel, a newly proposed type of inertial actuator that can generate torques in all three principal axes of a rigid satellite using a spinning wheel and a double tilt mechanism. The tilt mechanism tilts the angular momentum vector about two axes providing two degree of freedom control, while variation of the wheel speed provides the third. The equations of motion of the system lead to a singularity-free system during nominal operation avoiding the need for complex steering logic. This paper describes the hardware design of the tilted wheel and the experimental setup behind both standalone and spherical air-bearing tables used to test it. Experimental results from the air bearing table are provided with the results depicting the high performance capabilities of the proposed actuator in torque generation.

Epistemology and expectations survey about experimental physics: Development and initial results

Directory of Open Access Journals (Sweden)

Benjamin M. Zwickl

2014-06-01

Full Text Available In response to national calls to better align physics laboratory courses with the way physicists engage in research, we have developed an epistemology and expectations survey to assess how students perceive the nature of physics experiments in the contexts of laboratory courses and the professional research laboratory. The Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS evaluates students’ epistemology at the beginning and end of a semester. Students respond to paired questions about how they personally perceive doing experiments in laboratory courses and how they perceive an experimental physicist might respond regarding their research. Also, at the end of the semester, the E-CLASS assesses a third dimension of laboratory instruction, students’ reflections on their course’s expectations for earning a good grade. By basing survey statements on widely embraced learning goals and common critiques of teaching labs, the E-CLASS serves as an assessment tool for lab courses across the undergraduate curriculum and as a tool for physics education research. We present the development, evidence of validation, and initial formative assessment results from a sample that includes 45 classes at 20 institutions. We also discuss feedback from instructors and reflect on the challenges of large-scale online administration and distribution of results.

Mathematic Modeling of Experimental Results on the Influence of Technological Factors on Production in Some Energy Crops

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Mona CRISTESCU

2018-06-01

Full Text Available The present article, based on data obtained from a study which analyzed the influence of technological and ecological factors on rape plants (Brassica napus production capacity - the Bolero variety – approaches the model of linear regression and the model of the smallest squares. The experimental results were mathematically interpreted using the “variance analysis” method. The study shows that the yields and therefore the profit rate for the studied rapeseed variety was of up to 55, 05%, depending on the seeding density (in this case: 100 germinable seeds / m2 , level of fertilization, as well as on the pedo-climatic conditions of the area

An experimental method to determine the electrostatic field enhancement factor of a practical conductor surface

DEFF Research Database (Denmark)

McAllister, Iain Wilson; Crichton, George C

1989-01-01

A method of determining the field enhancement factor of a practical conductor is presented. The method is developed from a modified theory of discharge onset in a gaseous medium. This modification incorporates the influence of conductor surface roughness. Onset data from an experimental study...

Experimental results concerning global observables from the CERN SPS heavy ion program

International Nuclear Information System (INIS)

Young, G.R.

1990-06-01

A brief overview is given of experimental results obtained during the initial operation of the heavy-ion program at the CERN SPS during the period 1986--1988. This paper confines itself to a presentation of results on so-called global observables, such as energy flow and multiplicity distributions, and on information extracted from them. Of particular interest among the latter are an estimate of the magnitude and spatial distribution of the energy density attained. 3 refs., 27 figs

Utility of the microculture method in non-invasive samples obtained from an experimental murine model with asymptomatic leishmaniasis.

Science.gov (United States)

Allahverdiyev, Adil M; Bagirova, Malahat; Cakir-Koc, Rabia; Elcicek, Serhat; Oztel, Olga Nehir; Canim-Ates, Sezen; Abamor, Emrah Sefik; Yesilkir-Baydar, Serap

2012-07-01

The sensitivity of diagnostic methods for visceral leishmaniasis (VL) decreases because of the low number of parasites and antibody amounts in asymptomatic healthy donors who are not suitable for invasive sample acquisition procedures. Therefore, new studies are urgently needed to improve the sensitivity and specificity of the diagnostic approaches in non-invasive samples. In this study, the sensitivity of the microculture method (MCM) was compared with polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and immunofluorescent antibody test (IFAT) methods in an experimental murine model with asymptomatic leishmaniasis. Results showed that the percent of positive samples in ELISA, IFAT, and peripheral blood (PB) -PCR tests were 17.64%, 8.82%, and 5.88%, respectively, whereas 100% positive results were obtained with MCM and MCM-PCR methods. Thus, this study, for the first time, showed that MCM is more sensitive, specific, and economic than other methods, and the sensitivity of PCR that was performed to samples obtained from MCM was higher than sensitivity of the PCR method sampled by PB.

Stimulating Contributions to Public Goods through Information Feedback: Some Experimental Results.

Directory of Open Access Journals (Sweden)

Marco A Janssen

Full Text Available In traditional public good experiments participants receive an endowment from the experimenter that can be invested in a public good or kept in a private account. In this paper we present an experimental environment where participants can invest time during five days to contribute to a public good. Participants can make contributions to a linear public good by logging into a web application and performing virtual actions. We compared four treatments, with different group sizes and information of (relative performance of other groups. We find that information feedback about performance of other groups has a small positive effect if we control for various attributes of the groups. Moreover, we find a significant effect of the contributions of others in the group in the previous day on the number of points earned in the current day. Our results confirm that people participate more when participants in their group participate more, and are influenced by information about the relative performance of other groups.

Recent experimental results and diagnostics on LHD

International Nuclear Information System (INIS)

Kawahata, Kazuo

2001-01-01

LHD is a superconducting heliotron type device with 1=2/m=10 continuous helical coils and three pairs of poloidal coils. The major and minor radii of the plasma are 3.5-3.9 m and 0.6 m, respectively. The plasma experiment was started at the end of March 1998 with the magnetic field of 1.5 T. Subsequently, the magnetic field has been gradually increased checking carefully the stability of the SC coils, and the maximum magnetic field used in the plasma experiment was 2.89 T at the magnetic axis of R ax =3.6 m. The heating power has been gradually increased, i.e., NBI up to 5.2 MW (with two beam lines), ICRF up to 2.7 MW (with two antenna system), and ECRH up to 1.0 MW (with six gyrotron tubes). The carbon tiles were installed as divertor plates to meet high power heatings, resulting in significant reduction in metal impurity concentration (Fe) and total radiation power. Upgrading of the key hardware system has led to (i) higher Te [Te(0)=4.4 keV at =5.3x10 18 m -3 and P abs =1.8 MW], (ii) higher confinement [τ E =0.3 s, Te(0)=1.1 keV at =6.5x10 19 m -3 and P abs =2.0 MW], (iii) higher stored energy W p dia =1.0 MJ, (iv) the highest β value in helical devices [2.4% at 1.3 T, >30% at 0.5 T]. In this workshop, we will report the recent experimental results on the LHD and plasma diagnostics related to mm and sub-mm wave diagnostics. (author)

Experimental results of a direct air-cooled ammonia–lithium nitrate absorption refrigeration system

International Nuclear Information System (INIS)

Llamas-Guillén, S.U.; Cuevas, R.; Best, R.; Gómez, V.H.

2014-01-01

Absorption thermal cooling systems driven by renewable energy are a viable option in order to reduce fossil fuel consumption and the associated emissions. This work shows the results of an air cooled absorption cooling prototype working with an ammonia–lithium nitrate mixture at high ambient temperatures. An absorption refrigeration system was designed and built. The prototype is a one stage ammonia–lithium nitrate air cooled chiller. The experimental system was instrumented to evaluate each component. This paper shows the operation conditions in the experimental unit as well as some of the heat loads encountered at different operating conditions. The system was operated successfully at ambient temperatures in the range of 25–35 °C. A series of test showed that even at ambient temperatures it can be operated at evaporator temperatures below 10 °C producing chilled water for air conditioning applications such as radiative cooling panels. The system proved to stabilize very quickly and no risk of crystallization was encountered so the first results are promising in order to continue with the development of a more advanced prototype. - Highlights: •Experimental results of a direct air-cooled ammonia–lithium nitrate system. •The prototype is a one stage ammonia–lithium nitrate air cooled chiller. •The absorption system was operated successfully at ambient temperatures. •Cooling loads of 4.5 kW were reached in the chilled water side

Phase diagram Fe-Sn-Sr. New experimental results

International Nuclear Information System (INIS)

Nieva, N; Jimenez, M.J; Gomez, A; Corvalan Moya, C; Arias, D

2012-01-01

Zr-based alloys are widely used in nuclear industry due to their specific characteristics. The information of the phase diagrams of the ternary system Fe-Zr-Sn is scarce. In this work we investigate, in a experimental way, the central and the Fe-Sn binary adjacent regions of the Fe-Sn-Zr Gibbs triangle at the temperature of 800 o C. For the experimental work, a set of seven ternary alloys was designed, produced and examined by different complementary techniques. There were performed two types of heat treatments: one of medium and another of long duration. We present a new proposal for the 800 o C isothermal section. The boundaries of the identified phases and the fields of one, two and three phases are indicated in the diagram

Experimental Results of Network-Assisted Interference Suppression Scheme Using Adaptive Beam-Tilt Switching

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Tomoki Murakami

2017-01-01

Full Text Available This paper introduces a network-assisted interference suppression scheme using beam-tilt switching per frame for wireless local area network systems and its effectiveness in an actual indoor environment. In the proposed scheme, two access points simultaneously transmit to their own desired station by adjusting angle of beam-tilt including transmit power assisted from network server for the improvement of system throughput. In the conventional researches, it is widely known that beam-tilt is effective for ICI suppression in the outdoor scenario. However, the indoor effectiveness of beam-tilt for ICI suppression has not yet been indicated from the experimental evaluation. Thus, this paper indicates the effectiveness of the proposed scheme by analyzing multiple-input multiple-output channel matrices from experimental measurements in an office environment. The experimental results clearly show that the proposed scheme offers higher system throughput than the conventional scheme using just transmit power control.

Shear or bending? Experimental results on large t-shaped prestressed conrete beams

NARCIS (Netherlands)

Ensink, S.W.H.; Van der Veen, C.; De Boer, A.

2015-01-01

Experimental results of four shear tests on two large prestressed concrete beams are compared to nonlinear analysis and design code calculations. The beams have a length of 12 m and a depth of 1.3 m and are reinforced with stirrups and pre-tensioning. The four tests consist of a single point load at

TH-AB-BRA-12: Experimental Results From the First High-Field Inline MRI-Linac

Energy Technology Data Exchange (ETDEWEB)

Keall, P [University of Sydney, Camperdown, New South Wales (Australia); Dong, B; Zhang, K; Liney, G [Ingham Institute for Applied Medical Research, Liverpool, New South Wales (Australia); Vial, P; Walker, A; Begg, J; Rai, R [Liverpool Hospital, Sydney, New South Wales (Australia); Holloway, L; Barton, M [Ingham Institute for Applied Medical Research, Liverpool, New South Wales (Australia); Liverpool Hospital, Sydney, New South Wales (Australia); Crozier, S [University of Queensland, Brisbane, Queensland (Australia)

2016-06-15

Purpose: The pursuit of real-time image guided radiotherapy using optimal tissue contrast has seen the development of several hybrid MRI-treatment systems, high field and low field, and inline and perpendicular configurations. As part of a new MRI-Linac program, an MRI scanner was integrated with a linear accelerator to enable investigations of a coupled inline MRI-Linac system. This work describes our experimental results from the first high-field inline MRI-Linac. Methods: A 1.5 Tesla magnet (Sonata, Siemens) was located in a purpose built RF cage enabling shielding from and close proximity to a linear accelerator with inline orientation. A portable linear accelerator (Linatron, Varian) was installed together with a multi-leaf collimator (Millennium, Varian) to provide dynamic field collimation and the whole assembly built onto a stainless-steel rail system. A series of MRI-Linac experiments was performed to investigate: (1) image quality with beam on measured using a macropodine (kangaroo) ex vivo phantom; (2) the noise as a function of beam state measured using a 6-channel surface coil array and; (3) electron focusing measured using GafChromic film. Results: (1) The macropodine phantom image quality with the beam on was almost identical to that with the beam off. (2) Noise measured with a surface RF coil produced a 25% elevation of background noise when the radiation beam was on. (3) Film measurements demonstrated electron focusing occurring at the center of the radiation field. Conclusion: The first high-field MRI-Linac has been built and experimentally characterized. This system has allowed us to establish the efficacy of a high field in-line MRI-Linac and study a number of the technical challenges and solutions. Supported by the Australian National Health and Medical Research Council, the Australian Research Council, the Australian Cancer Research Foundation and the Health and Hospitals Fund.

Optimization of aspergillus niger nutritional conditions using statistical experimental methods for bio-recovery of manganese from pyrolusite

International Nuclear Information System (INIS)

Mujeeb-ur-Rahman; Yasinzai, M.M.; Tareen, R.B.; Iqbal, A.; Gul, S.; Odhano, E.A.

2011-01-01

Optimization of aspergillus niger nutritional conditions using statistical experimental methods for bio-recovery of manganese from pyrolusite Mujeeb-ur-rahman, Mohammed Masoom Yasinzai, Rasool Bakhsh Tareen, Asim Iqbal, Ejaz Ali Odhano, Shereen Gul. The nutritional requirements for Aspergillus niger PCSIR-06 for bio-recovery of manganese from pyrolusite ore were optimized. Box-Bhenken design and response surface methodology were used for designing of experiment and statistical analysis of the results. This procedure limited the number of actual experiments to 54 for studying the possible interaction between six nutrients. The optimum concentration of the nutrients were Sucrose 148.5 g/L, KH/sub 2/PO/sub 4/ 0.50 g/L, NH/sub 4/NO/sub 3/ 0.33 g/L, MgSO/sub 4/ 0.41 g/L, Zn 23.76 mg/L, Fe 0.18 mg/L for Aspergillus niger to achieve maximum bio-recovery of manganese (82.47 +- 5.67%). The verification run confirmed the predicted optimized concentration of all the six ingredients for maximum bio leaching of manganese and successfully confirmed the use of Box-Bhenken experimental design for maximum bio-recovery. Results also revealed that small and less time consuming experimental designs could be efficient for optimization of bio-recovery processes. (author)

Thermal properties of adobe employed in Peruvian rural areas: Experimental results and numerical simulation of a traditional bio-composite material

Directory of Open Access Journals (Sweden)

Ginés A. Abanto

2017-06-01

Different adobes have been studied. Effective thermal conductivity and heat capacity were measured by means of a hot parallel-plate method. Density was estimated using a pycnometer and measuring physical dimensions and mass of each sample, which allowed the calculation of thermal effusivity and diffusivity. Some numerical simulation results displayed good agreement with experimental outcomes. The work presented here has implications for future studies of this traditional building material and might potentially help solving the problem of sustainable housing.

Preface of "The Second Symposium on Border Zones Between Experimental and Numerical Application Including Solution Approaches By Extensions of Standard Numerical Methods"

Science.gov (United States)

Ortleb, Sigrun; Seidel, Christian

2017-07-01

In this second symposium at the limits of experimental and numerical methods, recent research is presented on practically relevant problems. Presentations discuss experimental investigation as well as numerical methods with a strong focus on application. In addition, problems are identified which require a hybrid experimental-numerical approach. Topics include fast explicit diffusion applied to a geothermal energy storage tank, noise in experimental measurements of electrical quantities, thermal fluid structure interaction, tensegrity structures, experimental and numerical methods for Chladni figures, optimized construction of hydroelectric power stations, experimental and numerical limits in the investigation of rain-wind induced vibrations as well as the application of exponential integrators in a domain-based IMEX setting.

Considerations that may influence the result of trials assessing tensile strength in experimental surgery Considerações que podem influir no resultado de pesquisas que avaliam a resistência tênsil em cirurgia experimental

Directory of Open Access Journals (Sweden)

Lucas Félix Rossi

2007-12-01

Full Text Available PURPOSE: To provide information gathered upon the execution of trials assessing tensile strength in experimental surgeries. METHODS: Descriptive study considering details on the execution of trials assessing tensile strength in experimental surgery. RESULTS: The analysis of the rupture force in a mechanical test machine is an adequate technique since it provides precise and quick results. It can, undoubtedly, be developed in this context of the eminently mechanical analysis of trials on experimental surgery. CONCLUSION: The utilization of a mechanical test machine is a useful tool in the assessment of materials' strength, providing accurate results. Nevertheless the trials must be well structured analyzing the multiple variables so as to attain a pattern of constant reproducibility and to provide the necessary reliability.OBJETIVO: Fornecer informações advindas da experiência com a realização de trabalhos que avaliam a resistência tênsil em cirurgia experimental. MÉTODOS: Estudo descritivo considerando detalhes da execução de trabalhos que avaliam a resistência tênsil em cirurgia experimental. RESULTADOS: A análise da força de ruptura em máquina de ensaios mecânicos é uma técnica apropriada e que fornece resultados precisos e rápidos. Pode ser desenvolvida neste contexto da análise eminentemente mecânica de estudos em cirurgia experimental. CONCLUSÃO: A utilização da máquina de ensaios mecânicos é uma ferramenta útil na avaliação da resistência de materiais fornecendo resultados precisos. Entretanto os trabalhos devem ser estruturados analisando múltiplas variáveis para alcançar um padrão de reprodutibilidade constante e trazer a confiabilidade necessária ao estudo.

New experimental results on beam-plasma interaction in solenoids

International Nuclear Information System (INIS)

Arzhannikov, A.V.; Burdakov, A.V.; Kapitonov, V.A.

1988-01-01

New results are presented on studying the beam-plasma interaction and plasma heating dynamics at the INAR device. The specific features of the generation of ''hot'' (E greater than or ∼ 1 keV) plasma electrons containing the main part of the plasma energy are studied. In the case of a beam with a small initial angular spread, the ''hot'' electrons are shown to be mainly generated near the point where the beam is injected into the plasma. Also reported are the results of the experiments in which the magnetic field in the beam-plasma interaction region was increased up to 70 kOe. In this case, at the plasma length of 75 cm, the total beam energy losses exceed 40%. The growth of the plasma energy content at higher magnetic field is observed. The first stage of the GOL-3 experiment is described which is aimed at the study of the plasma heating is solonoid by a 100 kJ microsecond electron beam. This new experimental device is now ready for operation (author)

Inferring regulatory networks from experimental morphological phenotypes: a computational method reverse-engineers planarian regeneration.

Directory of Open Access Journals (Sweden)

Daniel Lobo

2015-06-01

Full Text Available Transformative applications in biomedicine require the discovery of complex regulatory networks that explain the development and regeneration of anatomical structures, and reveal what external signals will trigger desired changes of large-scale pattern. Despite recent advances in bioinformatics, extracting mechanistic pathway models from experimental morphological data is a key open challenge that has resisted automation. The fundamental difficulty of manually predicting emergent behavior of even simple networks has limited the models invented by human scientists to pathway diagrams that show necessary subunit interactions but do not reveal the dynamics that are sufficient for complex, self-regulating pattern to emerge. To finally bridge the gap between high-resolution genetic data and the ability to understand and control patterning, it is critical to develop computational tools to efficiently extract regulatory pathways from the resultant experimental shape phenotypes. For example, planarian regeneration has been studied for over a century, but despite increasing insight into the pathways that control its stem cells, no constructive, mechanistic model has yet been found by human scientists that explains more than one or two key features of its remarkable ability to regenerate its correct anatomical pattern after drastic perturbations. We present a method to infer the molecular products, topology, and spatial and temporal non-linear dynamics of regulatory networks recapitulating in silico the rich dataset of morphological phenotypes resulting from genetic, surgical, and pharmacological experiments. We demonstrated our approach by inferring complete regulatory networks explaining the outcomes of the main functional regeneration experiments in the planarian literature; By analyzing all the datasets together, our system inferred the first systems-biology comprehensive dynamical model explaining patterning in planarian regeneration. This method

Automation in dairy cattle milking: experimental results and considerations

Directory of Open Access Journals (Sweden)

Marisanna Speroni

2010-01-01

Full Text Available The results of two experimental programs financed to the Istituto Sperimentale per la Zootecnia are presented. The objective of the two Italian programs was the verify if automatic milking is a suitable practice for Italian dairy system. Results are summarised and compared to those obtained in other international projects. Results refer to animal behaviour, milk yield, milk quality an animal welfare. In a trial comparing cows milked with an automatic milking system and cows milked in a milking parlour, we observed that when the temperature and humidity are very high cows reduce their activity, have lower milking frequency and milk yield than in cold seasons. In comparison to milking parlour, automatic milking system did not increase milk yield which was affected significantly by season, stage of lactation, parity, season per treatment and parity per treatment. The causes of the negative results obtained by this group and by other international groups are discussed. We also presented the results obtained in four trials thereby four appetizers or flavourings were tested to improve efficiency of automatic milking system. Comparing the two milking systems, automatic milking determined a worsening of milk quality, but from these data is not possible to exclude the possibility to use automatic milking for Grana Padano and Parmigiano Reggiano-type cheeses. Animal welfare is not negatively influenced by automatic milking system, which has the potentiality to improve the control and care of cows.

Analysis of progressive distorsion. Validation of the method based on effective primary stress. Discussion of Anderson's experimental data

International Nuclear Information System (INIS)

Moulin, Didier.

1981-02-01

An empirical rule usable for design by analysis against progressive distorsion has been set up from experiments conducted in C.E.N. Saclay. This rule is checked with experimental data obtained by W.F. ANDERSON, this experiment is sufficiently different from the Saclay one to evaluate the merits of the rule. The satisfactory results achieved, are another validation of the efficiency diagram on which the method is based [fr

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)

Experimental thermodynamics experimental thermodynamics of non-reacting fluids

CERN Document Server

Neindre, B Le

2013-01-01

Experimental Thermodynamics, Volume II: Experimental Thermodynamics of Non-reacting Fluids focuses on experimental methods and procedures in the study of thermophysical properties of fluids. The selection first offers information on methods used in measuring thermodynamic properties and tests, including physical quantities and symbols for physical quantities, thermodynamic definitions, and definition of activities and related quantities. The text also describes reference materials for thermometric fixed points, temperature measurement under pressures, and pressure measurements. The publicatio

Theoretical and experimental investigation of multispectral photoacoustic osteoporosis detection method

Science.gov (United States)

Steinberg, Idan; Hershkovich, Hadas Sara; Gannot, Israel; Eyal, Avishay

2014-03-01

Osteoporosis is a widespread disorder, which has a catastrophic impact on patients lives and overwhelming related to healthcare costs. Recently, we proposed a multispectral photoacoustic technique for early detection of osteoporosis. Such technique has great advantages over pure ultrasonic or optical methods as it allows the deduction of both bone functionality from the bone absorption spectrum and bone resistance to fracture from the characteristics of the ultrasound propagation. We demonstrated the propagation of multiple acoustic modes in animal bones in-vitro. To further investigate the effects of multiple wavelength excitations and of induced osteoporosis on the PA signal a multispectral photoacoustic system is presented. The experimental investigation is based on measuring the interference of multiple acoustic modes. The performance of the system is evaluated and a simple two mode theoretical model is fitted to the measured phase signals. The results show that such PA technique is accurate and repeatable. Then a multiple wavelength excitation is tested. It is shown that the PA response due to different excitation wavelengths revels that absorption by the different bone constitutes has a profound effect on the mode generation. The PA response is measured in single wavelength before and after induced osteoporosis. Results show that induced osteoporosis alters the measured amplitude and phase in a consistent manner which allows the detection of the onset of osteoporosis. These results suggest that a complete characterization of the bone over a region of both acoustic and optical frequencies might be used as a powerful tool for in-vivo bone evaluation.

Analytical, Numerical, and Experimental Investigation on a Non-Contact Method for the Measurements of Creep Properties of Ultra-High-Temperature Materials

Science.gov (United States)

Lee, Jonghyun; Hyers, Robert W.; Rogers, Jan R.; Rathz, Thomas J.; Choo, Hahn; Liaw, Peter

2006-01-01

Responsive access to space requires re-use of components such as rocket nozzles that operate at extremely high temperatures. For such applications, new ultra-hightemperature materials that can operate over 2,000 C are required. At the temperatures higher than the fifty percent of the melting temperature, the characterization of creep properties is indispensable. Since conventional methods for the measurement of creep is limited below 1,700 C, a new technique that can be applied at higher temperatures is strongly demanded. This research develops a non-contact method for the measurement of creep at the temperatures over 2,300 C. Using the electrostatic levitator in NASA MSFC, a spherical sample was rotated to cause creep deformation by centrifugal acceleration. The deforming sample was captured with a digital camera and analyzed to measure creep deformation. Numerical and analytical analyses have also been conducted to compare the experimental results. Analytical, numerical, and experimental results showed a good agreement with one another.

Performance limits of direct cryogenically cooled silicon monochromators - experimental results at the APS

International Nuclear Information System (INIS)

Lee, W.-K.; Fernandez, P.; Mills, D.M.

2000-01-01

The successful use of cryogenically cooled silicon monochromators at third-generation synchrotron facilities is well documented. At the Advanced Photon Source (APS) it has been shown that, at 100 mA operation with the standard APS undulator A, the cryogenically cooled silicon monochromator performs very well with minimal (<2 arcsec) or no observable thermal distortions. However, to date there has not been any systematic experimental study on the performance limits of this approach. This paper presents experimental results on the performance limits of these directly cooled crystals. The results show that if the beam is limited to the size of the radiation central cone then, at the APS, the crystal will still perform well at twice the present 100 mA single 2.4 m-long 3.3 cm-period undulator heat load. However, the performance would degrade rapidly if a much larger incident white-beam size is utilized

Experimental comparison of the different methods for seismic qualification of electrical cabinets

International Nuclear Information System (INIS)

Buland, P.; Gauthier, G.; Simon, D.

1993-01-01

This paper presents the results of an experimental seismic study performed on a cabinet equipped with 96 acceleration sensitive relays located in four racks. The aim of this study is to verify the validity of the seismic qualification method proposed in the IEC 980 standard. The cabinet was primarily tested on a shaking table and the relay chatter was monitored. The interactions between the racks and the cabinet frame induce shocks which were correlated with some of the contact openings. The racks were afterwards tested individually with the accelerations recorded during the cabinet test. A comparison of relay chatter was performed for both test phases. An important reduction of relay chatter was noticed during the racks test. This is due to the fact that it is not possible to fully represent on shaking table the complex vibration environment (shocks) sustained by a rack in a cabinet

Study on the Growth of Holes in Cold Spraying via Numerical Simulation and Experimental Methods

Directory of Open Access Journals (Sweden)

Guosheng Huang

2016-12-01

Full Text Available Cold spraying is a promising method for rapid prototyping due to its high deposition efficiency and high-quality bonding characteristic. However, many researchers have noticed that holes cannot be replenished and will grow larger and larger once formed, which will significantly decrease the deposition efficiency. No work has yet been done on this problem. In this paper, a computational simulation method was used to investigate the origins of these holes and the reasons for their growth. A thick copper coating was deposited around the pre-drilled, micro-size holes using a cold spraying method on copper substrate to verify the simulation results. The results indicate that the deposition efficiency inside the hole decreases as the hole become deeper and narrower. The repellant force between the particles perpendicular to the impaction direction will lead to porosity if the particles are too close. There is a much lower flattening ratio for successive particles if they are too close at the same location, because the momentum energy contributes to the former particle’s deformation. There is a high probability that the above two phenomena, resulting from high powder-feeding rate, will form the original hole, which will grow larger and larger once it is formed. It is very important to control the powder feeding rate, but the upper limit is yet to be determined by further simulation and experimental investigation.

Experimental Method For Studying Habitual Behavior In Food Consumption

Directory of Open Access Journals (Sweden)

Naziha Kasraoui

2015-03-01

Full Text Available Abstract To investigate the process of habit formation in everyday life a sample of 126 participants students chooses an eating and drinking for three periods weeks. They completed the self-report habit each period and we have recorded their choices. All participants provided sufficient data for analysis and collected experimental data were examined over the study periods 3 weeks. Experimental analysis was used to examine the persistence of habit formation process in the behavior of participants. The game is carried out with 126 students and repeated for three periods. Using experimental laboratory data approach and economic analysis elasticity results show that into the presence of labor income and for 126 students of whom approximately 70 showed that habit formation process is persist in their behaviors along the three periods. The rest 30 of them who dont present habit formation in their behavior for the three periods did not materially affect our conclusion about the assumption of habit formation process. Participants to the game persistently spend too much in early periods they learn rapidly from their own experience to consume the same choice of meals and drinks. Their spending is closely linked to optimal consumption non conditional on earlier spending and they choose the same basket of goods in the future horizon which shows that theres a habit formation in the behaviors of participants.

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.

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

Processing considerations with plasma-based ion implantation of polymers: theoretical aspects, limitations, and experimental results

International Nuclear Information System (INIS)

Lacoste, A.; Pelletier, J.

2003-01-01

Processing of polymers using plasma-based ion implantation techniques (PBII) has general implications in terms of plasma specifications and pulse characteristics. In particular, the different aspects of the processing of polymer layers are discussed as functions of plasma density, pulse duration, and layer characteristics (thickness and permittivity). Clearly, severe limitations (true implantation energy, arcing) may appear for high-density plasmas as well as for long pulse durations, when processing polymer layers with thickness in the mm range. A review of the experimental results of ion implantation in polymeric materials via PBII processing is presented. The experimental results demonstrate the possibility of processing polymer layers with the PBII technique, but with severe limitations resulting from the process itself

The results of decontamination and decommissioning of experimental DUPIC equipment at PIEF 9405 hot cell

Energy Technology Data Exchange (ETDEWEB)

Lee, H. H.; Park, J. J.; Shin, J. M.; Cho, K. H.; Yang, M. S.; Lee, E. P. [Korea Atomic Energy Research Institute, Taejeon (Korea)

2002-02-01

The characterization experiment for powder and sintered fuel had been performed using about 1 kg-U spent PWR fuel at No. 9405 hot-cell in PIEF(Post Irradiated Experiment Facility) since early in 1999. Currently, the experiments in PIEF have been completed. Since all DUPIC equipment in hot-cell are contaminated by high radioactive material, the decontamination and dismantlement must be performed remotely by M/S manipulator. During the radioactive waste packing and transportation, the reduction method of radiation exposure has to be considered. This report describes the basic plan for dismantlement/decontamination of the characterization equipment (power and sintered fuel). And methods of measurement/packing/transportation, method of dismantlement/decontamination of the experimental apparatus and the reduction method of radiation dose exposure, etc. are explained in order. 7 refs., 42 figs., 10 tabs. (Author)

Experimental Analysis of a Heat Cost Allocation Method for Apartment Buildings

Directory of Open Access Journals (Sweden)

Fabio Saba

2017-03-01

Full Text Available The correct estimate of individual thermal energy consumptions, and consequently, a fair heat cost allocation among the residents of apartment buildings with centralized heating systems, represents an important driving force towards energy saving, energy efficiency and the reduction of pollutant emissions. Nowadays, in those contexts where direct heat meters cannot be used because of the layout of the hot water distribution system, electronic Heat Cost Allocators (HCAs have the highest market share for the assessment of individual thermal energy consumptions. The uncertainty associated with the parameterization of heat cost allocation devices and the installation effects arising in real applications can negatively affect the accuracy of these devices, as far as the estimation of the individual fractions of thermal energy consumption is concerned. This work deals with the experimental analysis of a novel heat cost allocation method for apartment buildings and its comparison with conventional HCAs. The method allows the indirect estimation of the thermal energy exchanged by water radiators without the need for surface temperature measurements, reducing some of the drawbacks associated with the on-site installation. The experimental analysis was carried out in a full-scale central heating system test facility available at the Italian National Metrology Institute (INRIM and characterized by SI-traceable direct heat meters installed on each water radiator.

Comparison of numerical results with experimental data for single-phase natural convection in an experimental sodium loop

International Nuclear Information System (INIS)

Ribando, R.J.

1979-01-01

A comparison is made between computed results and experimental data for a single-phase natural convection test in an experimental sodium loop. The test was conducted in the Thermal-Hydraulic Out-of-Reactor Safety (THORS) facility, an engineering-scale high temperature sodium loop at the Oak Ridge National Laboratory (ORNL) used for thermal-hydraulic testing of simulated Liquid Metal Fast Breeder Reactor (LMFBR) subassemblies at normal and off-normal operating conditions. Heat generation in the 19 pin assembly during the test was typical of decay heat levels. The test chosen for analysis in this paper was one of seven natural convection runs conducted in the facility using a variety of initial conditions and testing parameters. Specifically, in this test the bypass line was open to simulate a parallel heated assembly and the test was begun with a pump coastdown from a small initial forced flow. The computer program used to analyze the test, LONAC (LOw flow and NAtural Convection) is an ORNL-developed, fast-running, one-dimensional, single-phase, finite-difference model used for simulating forced and free convection transients in the THORS loop

Comparison of typical inelastic analysis predictions with benchmark problem experimental results

International Nuclear Information System (INIS)

Clinard, J.A.; Corum, J.M.; Sartory, W.K.

1975-01-01

The results of exemplary inelastic analyses are presented for a series of experimental benchmark problems. Consistent analytical procedures and constitutive relations were used in each of the analyses, and published material behavior data were used in all cases. Two finite-element inelastic computer programs were employed. These programs implement the analysis procedures and constitutive equations for Type 304 stainless steel that are currently used in many analyses of elevated-temperature nuclear reactor system components. The analysis procedures and constitutive relations are briefly discussed, and representative analytical results are presented and compared to the test data. The results that are presented demonstrate the feasibility of performing inelastic analyses, and they are indicative of the general level of agreement that the analyst might expect when using conventional inelastic analysis procedures. (U.S.)

[Experimental Methods and Result Analysis of a Variety of Spectral Reflectance Properties of the Thin Oil Film].

Science.gov (United States)

Ye, Zhou; Liu, Li; Wei, Chuan-xin; Gu, Qun; An, Ping-ao; Zhao, Yue-jiao; Yin, Da-yi

2015-06-01

In order to analysis the oil spill situation based on the obtained data in airborne aerial work, it's needed to get the spectral reflectance characteristics of the oil film of different oils and thickness as support and to select the appropriate operating band. An experiment is set up to measure the reflectance spectroscopy from ultraviolet to near-infrared for the film of five target samples, which means petrol, diesel, lubricating oil, kerosene and fossil, using spectral measurement device. The result is compared with the reflectance spectra of water in the same experimental environment, which shows that the spectral reflection characteristics of the oil film are related to the thickness and the type of the oil film. In case of the same thickness, the spectral reflectance curve of different types of film is far different, and for the same type of film, the spectral reflectance curve changes accordingly with the change of film thickness, therefore in terms of the single film, different film thickness can be distinguished by reflectance curves. It also shows that in terms of the same film thickness, the reflectance of diesel, kerosene, lubricants reaches peak around 380 nm wavelength, obviously different from the reflectance of water, and that the reflectance of crude oil is far less than that of water in more than 340 nm wavelength, and the obtained reflection spectrum can be used to distinguish between different types of oil film to some extent. The experiment covers main types of spilled oil, with data comprehensively covering commonly used detect spectral bands, and quantitative description of the spectral reflectance properties of film. It provides comprehensive theoretical and data support for the selection of airborne oil spill detection working band and the detection and analysis of water-surface oil spill.

Uncertainties and understanding of experimental and theoretical results regarding reactions forming heavy and superheavy nuclei

Science.gov (United States)

Giardina, G.; Mandaglio, G.; Nasirov, A. K.; Anastasi, A.; Curciarello, F.; Fazio, G.

2018-02-01

Experimental and theoretical results of the PCN fusion probability of reactants in the entrance channel and the Wsur survival probability against fission at deexcitation of the compound nucleus formed in heavy-ion collisions are discussed. The theoretical results for a set of nuclear reactions leading to formation of compound nuclei (CNs) with the charge number Z = 102- 122 reveal a strong sensitivity of PCN to the characteristics of colliding nuclei in the entrance channel, dynamics of the reaction mechanism, and excitation energy of the system. We discuss the validity of assumptions and procedures for analysis of experimental data, and also the limits of validity of theoretical results obtained by the use of phenomenological models. The comparison of results obtained in many investigated reactions reveals serious limits of validity of the data analysis and calculation procedures.

Tests of experimental fuel elements by the method of nuclear-thermal pulse loadings in 'HYDRA' reactor

International Nuclear Information System (INIS)

Nastoyashchaya, O.V.; Lebedev, Yu. M.; Chechurov, A.M.; Khvostionov, Ye

1997-01-01

The results of tests of experimental fuel elements with uranium dioxide fuel composition embedded in Al and Zr matrix with the enrichment from 90% to 36% in respect to U-235 performed at the pulse 'HYDRA' reactor are presented in this paper. Testing is performed in the frame-work of extensive research program studying the behavior of fuel elements (FE) of research and mini nuclear power systems in case of practically immediate energy release in the fuel taking place during the RIA-type accidents. Duration of the neutron pulse when testing in 'HYDRA' reactor is from 7 to 20 ms. The methods of diagnostics of the state of FE prior to and after testing in the reactor are developed and verified. Mathematical model describing temperature fields inside the FE in the process of testing. and accounting for non-uniformity of fuel composition has been developed in order to summarize experimental results. Experimental data on the limiting values of the energy density leading to deformation and degradation of FE depending on the type of fuel composition have been obtained and the mechanisms for the development of these processes have been determined. The nature of physical-chemical processes taking place in the fuel composition and fuel cladding depending on material composition under different levels of energy deposition is demonstrated. The data on hydrogen generation and radioactive product release out of fuel after failure of FE are presented. (author)

A novel full-field experimental method to measure the local compressibility of gas diffusion media

Energy Technology Data Exchange (ETDEWEB)

Lai, Yeh-Hung; Li, Yongqiang [Electrochemical Energy Research Lab, GM R and D, Honeoye Falls, NY 14472 (United States); Rock, Jeffrey A. [GM Powertrain, Honeoye Falls, NY 14472 (United States)

2010-05-15

The gas diffusion medium (GDM) in a proton exchange membrane (PEM) fuel cell needs to simultaneously satisfy the requirements of transporting reactant gases, removing product water, conducting electrons and heat, and providing mechanical support to the membrane electrode assembly (MEA). Concerning the localized over-compression which may force carbon fibers and other conductive debris into the membrane to cause fuel cell failure by electronically shorting through the membrane, we have developed a novel full-field experimental method to measure the local thickness and compressibility of GDM. Applying a uniform air pressure upon a thin polyimide film bonded on the top surface of the GDM with support from the bottom by a flat metal substrate and measuring the thickness change using the 3-D digital image correlation technique with an out-of-plane displacement resolution less than 0.5 {mu}m, we have determined the local thickness and compressive stress/strain behavior in the GDM. Using the local thickness and compressibility data over an area of 11.2 mm x 11.2 mm, we numerically construct the nominal compressive response of a commercial Toray trademark TGP-H-060 based GDM subjected to compression by flat platens. Good agreement in the nominal stress/strain curves from the numerical construction and direct experimental flat-platen measurement confirms the validity of the methodology proposed in this article. The result shows that a nominal pressure of 1.4 MPa compressed between two flat platens can introduce localized compressive stress concentration of more than 3 MPa in up to 1% of the total area at various locations from several hundred micrometers to 1 mm in diameter. We believe that this full-field experimental method can be useful in GDM material and process development to reduce the local hard spots and help to mitigate the membrane shorting failure in PEM fuel cells. (author)

A novel full-field experimental method to measure the local compressibility of gas diffusion media

Science.gov (United States)

Lai, Yeh-Hung; Li, Yongqiang; Rock, Jeffrey A.

The gas diffusion medium (GDM) in a proton exchange membrane (PEM) fuel cell needs to simultaneously satisfy the requirements of transporting reactant gases, removing product water, conducting electrons and heat, and providing mechanical support to the membrane electrode assembly (MEA). Concerning the localized over-compression which may force carbon fibers and other conductive debris into the membrane to cause fuel cell failure by electronically shorting through the membrane, we have developed a novel full-field experimental method to measure the local thickness and compressibility of GDM. Applying a uniform air pressure upon a thin polyimide film bonded on the top surface of the GDM with support from the bottom by a flat metal substrate and measuring the thickness change using the 3-D digital image correlation technique with an out-of-plane displacement resolution less than 0.5 μm, we have determined the local thickness and compressive stress/strain behavior in the GDM. Using the local thickness and compressibility data over an area of 11.2 mm × 11.2 mm, we numerically construct the nominal compressive response of a commercial Toray™ TGP-H-060 based GDM subjected to compression by flat platens. Good agreement in the nominal stress/strain curves from the numerical construction and direct experimental flat-platen measurement confirms the validity of the methodology proposed in this article. The result shows that a nominal pressure of 1.4 MPa compressed between two flat platens can introduce localized compressive stress concentration of more than 3 MPa in up to 1% of the total area at various locations from several hundred micrometers to 1 mm in diameter. We believe that this full-field experimental method can be useful in GDM material and process development to reduce the local hard spots and help to mitigate the membrane shorting failure in PEM fuel cells.

Experimental and raytrace results for throat-to-throat compound parabolic concentrators

Science.gov (United States)

Leviton, D. B.; Leitch, J. W.

1986-01-01

Compound parabolic concentrators are nonimaging cone-shaped optics with useful angular transmission characteristics. Two cones used throat-to-throat accept radiant flux within one well-defined acceptance angle and redistribute it into another. If the entrance cone is fed with Lambertian flux, the exit cone produces a beam whose half-angle is the exit cone's acceptance angle and whose cross section shows uniform irradiance from near the exit mouth to infinity. (The pair is a beam angle transformer). The design of one pair of cones is discussed, also an experiment to map the irradiance of the emergent beam, and a raytracing program which models the cones fed by Lambertian flux. Experimental results compare favorably with raytrace results.

Review of recent irradiation-creep results

International Nuclear Information System (INIS)

Coghlan, W.A.

1982-05-01

Materials deform faster under stress in the presence of irradiation by a process known as irradiation creep. This phenomenon is important to reactor design and has been the subject of a large number of experimental and theoretical investigations. The purpose of this work is to review the recent experimental results to obtain a summary of these results and to determine those research areas that require additional information. The investigations have been classified into four subgroups based on the different experimental methods used. These four are: (1) irradiation creep using stress relaxation methods, (2) creep measurements using pressurized tubes, (3) irradiation creep from constant applied load, and (4) irradiation creep experiments using accelerated particles. The similarity and the differences of the results from these methods are discussed and a summary of important results and suggested areas for research is presented. In brief, the important results relate to the dependence of creep on swelling, temperature, stress state and alloying additions. In each of these areas new results have been presented and new questions have arisen which require further research to answer. 65 references

Updating experimental results on light meson spectroscopy

International Nuclear Information System (INIS)

Diekmann, B.

1991-06-01

A recollection and summary is given on the understanding of light qanti q (q = u,d,s) mesons under the regime of the qanti q potential turning from a coulombic behaviour to a 'confining' one. In the second part the experimental knowledge obtained in the last years is updated: e + e - experiments, fixed target experiments with hadrons (kaons) and photons and panti p annihilations at LEAR discovered unknown objects and added new constraints on known but not fully understood states. (orig.)

Assessment of the Contour Method for 2-D Cross Sectional Residual Stress Measurements of Friction Stir Welded Parts of AA2024-T3—Numerical and Experimental Comparison

DEFF Research Database (Denmark)

Sonne, Mads Rostgaard; Carlone, Pierpaolo; Hattel, Jesper Henri

2017-01-01

The contour method is one of the newest techniques for obtaining residual stress fields from friction stir welded (FSW) parts, experimentally. This method has many advantages; however, edge effects coming from the process itself might introduce artifacts in the obtained results, and this was slig......The contour method is one of the newest techniques for obtaining residual stress fields from friction stir welded (FSW) parts, experimentally. This method has many advantages; however, edge effects coming from the process itself might introduce artifacts in the obtained results......) cross sectional map obtained by the method, peak stresses in tension are observed in the mid-section of the FSW butt-welded plates at the distance of the tool radius from the centerline. The corresponding numerical simulation indicates the same behavior because of the particular clamping conditions...

Effect of Chemistry Triangle Oriented Learning Media on Cooperative, Individual and Conventional Method on Chemistry Learning Result

Science.gov (United States)

Latisma D, L.; Kurniawan, W.; Seprima, S.; Nirbayani, E. S.; Ellizar, E.; Hardeli, H.

2018-04-01

The purpose of this study was to see which method are well used with the Chemistry Triangle-oriented learning media. This quasi experimental research involves first grade of senior high school students in six schools namely each two SMA N in Solok city, in Pasaman and two SMKN in Pariaman. The sampling technique was done by Cluster Random Sampling. Data were collected by test and analyzed by one-way anova and Kruskall Wallish test. The results showed that the high school students in Solok learning taught by cooperative method is better than the results of student learning taught by conventional and Individual methods, both for students who have high initial ability and low-ability. Research in SMK showed that the overall student learning outcomes taught by conventional method is better than the student learning outcomes taught by cooperative and individual methods. Student learning outcomes that have high initial ability taught by individual method is better than student learning outcomes that are taught by cooperative method and for students who have low initial ability, there is no difference in student learning outcomes taught by cooperative, individual and conventional methods. Learning in high school in Pasaman showed no significant difference in learning outcomes of the three methods undertaken.

Experimental validation of the twins prediction program for rolling noise. Pt.2: results

NARCIS (Netherlands)

Thompson, D.J.; Fodiman, P.; Mahé, H.

1996-01-01

Two extensive measurement campaigns have been carried out to validate the TWINS prediction program for rolling noise, as described in part 1 of this paper. This second part presents the experimental results of vibration and noise during train pass-bys and compares them with predictions from the

Experimental Study on Welded Headed Studs Used In Steel Plate-Concrete Composite Structures Compared with Contactless Method of Measuring Displacement

Science.gov (United States)

Kisała, Dawid; Tekieli, Marcin

2017-10-01

Steel plate-concrete composite structures are a new innovative design concept in which a thin steel plate is attached to the reinforced concrete beam by means of welded headed studs. The comparison between experimental studies and theoretical analysis of this type of structures shows that their behaviour is dependent on the load-slip relationship of the shear connectors used to ensure sufficient bond between the concrete and steel parts of the structure. The aim of this paper is to describe an experimental study on headed studs used in steel plate-concrete composite structures. Push-out tests were carried out to investigate the behaviour of shear connectors. The test specimens were prepared according to standard push-out tests, however, instead of I-beam, a steel plate 16 mm thick was used to better reflect the conditions in the real structure. The test specimens were produced in two batches using concrete with significantly different compressive strength. The experimental study was carried out on twelve specimens. Besides the traditional measurements based on LVDT sensors, optical measurements based on the digital image correlation method (DIC) and pattern tracking methods were used. DIC is a full-field contactless optical method for measuring displacements in experimental testing, based on the correlation of the digital images taken during test execution. With respect to conventional methods, optical measurements offer a wider scope of results and can give more information about the material or construction behaviour during the test. The ultimate load capacity and load-slip curves obtained from the experiments were compared with the values calculated based on Eurocodes, American and Chinese design specifications. It was observed that the use of the relationships developed for the traditional steel-concrete composite structures is justified in the case of ultimate load capacity of shear connectors in steel plate-concrete composite structures.

Experimental results of the effective water head in downcomer during reflood phase of a PWR LOCA

International Nuclear Information System (INIS)

Sudo, Yukio; Murao, Yoshio; Akimoto, Hajime

1980-08-01

The results and analysis of an experiment for the effective water head in downcomer with 50mm gap size are described. The main objective of the experiment was to clarify the effect of gap size on reflooding in a PWR LOCA. The effective water head in downcomer is the driving force for feeding emergency coolant into the core during reflood phase of a PWR LOCA. Discussions presented here follow those of a previous report in which experimental results and analysis were described for the case of 200mm gap size. Experimental Conditions were: Initial Wall Temperature = 200 -- 300 0 C, Back Pressure = 1 atm., Coolant Temperature = 71 -- 100 0 C, Extraction Water Velocity = 0 -- 2 cm/s, Gap Size = 50 mm. The effective water head history obtained in the experiment was compared with those predicted with Sudo's void fraction correlation. In the prediction, heat input to coolant was calculated from the response of measured wall temperature with heat condition analysis. The experimental results and analysis reveals that: (1) The effects of the gap size and initial wall temperature are evident, (2) The effect of extraction water velocity is negligible, and (3) The predicted history of effective water head is in good agreement with the experimental results except during the transient period in which the effective water head is descreasing. (author)

Out-of-plane buckling of pantographic fabrics in displacement-controlled shear tests: experimental results and model validation

Science.gov (United States)

Barchiesi, Emilio; Ganzosch, Gregor; Liebold, Christian; Placidi, Luca; Grygoruk, Roman; Müller, Wolfgang H.

2018-01-01

Due to the latest advancements in 3D printing technology and rapid prototyping techniques, the production of materials with complex geometries has become more affordable than ever. Pantographic structures, because of their attractive features, both in dynamics and statics and both in elastic and inelastic deformation regimes, deserve to be thoroughly investigated with experimental and theoretical tools. Herein, experimental results relative to displacement-controlled large deformation shear loading tests of pantographic structures are reported. In particular, five differently sized samples are analyzed up to first rupture. Results show that the deformation behavior is strongly nonlinear, and the structures are capable of undergoing large elastic deformations without reaching complete failure. Finally, a cutting edge model is validated by means of these experimental results.

An equivalent method for optimization of particle tuned mass damper based on experimental parametric study

Science.gov (United States)

Lu, Zheng; Chen, Xiaoyi; Zhou, Ying

2018-04-01

A particle tuned mass damper (PTMD) is a creative combination of a widely used tuned mass damper (TMD) and an efficient particle damper (PD) in the vibration control area. The performance of a one-storey steel frame attached with a PTMD is investigated through free vibration and shaking table tests. The influence of some key parameters (filling ratio of particles, auxiliary mass ratio, and particle density) on the vibration control effects is investigated, and it is shown that the attenuation level significantly depends on the filling ratio of particles. According to the experimental parametric study, some guidelines for optimization of the PTMD that mainly consider the filling ratio are proposed. Furthermore, an approximate analytical solution based on the concept of an equivalent single-particle damper is proposed, and it shows satisfied agreement between the simulation and experimental results. This simplified method is then used for the preliminary optimal design of a PTMD system, and a case study of a PTMD system attached to a five-storey steel structure following this optimization process is presented.

Some experimental results of the investigation of hadron-nucleus and nucleus-nucleus interactions

International Nuclear Information System (INIS)

Azimov, S.A.; Gulamov, K.G.; Chernov, G.M.

1978-01-01

Recent experimental data on the hadron-nucleus and nucleus-nucleus inelastic interactions are analyzed. A particular attention is paid to the description of the leading hadron spectra and of the spectra of nucleon recoils in hadron-nucleus interactions. Some of the results of the experimental studies of correlations between secondary particles are discussed. This discussion demonstrates that an analysis of the multiparticle phenomena is very promising regarding the discrimination between the different models for the hadron-nucleus and nucleus-nucleus interactions. It is pointed out that the actual mechanism of the hadron-nucleus and nucleus-nucleus interactions is a rather complex one and can be described comprehensively by none of the existing models

Uranium dioxide-sodium interactions. Development of a theoretical model. Fitting of this model to the experimental results

International Nuclear Information System (INIS)

Syrmalenios, Panayotis

1973-01-01

This research thesis addresses the issue of safety of fast neutron reactors, and more particularly is a contribution of the study of mechanisms of interaction between molten fuel and sodium. It aims at developing tools of prediction of consequences of three main types of accidents: local fusion of a fuel rod and contact of the fuel with the surrounding sodium, failure of an assembly due to the fusion of several rods and fuel-coolant interaction within the assembly, and fuel-coolant interaction at the level of the reactor core. The author first proposes a bibliographical analysis of experimental and theoretical studies related to this issue of interaction between a hot body and a cold liquid, and of its consequences. Then, he introduces a mathematical model and its resolution method, and reports the use of the associated code (Corfou) for the interpretation of experimental results: expulsion of cold sodium column by expansion of an overheated sodium mass, fusion of a rod by Joule effect, interaction between UO_2 molten by high frequency with liquid sodium. Finally, the author discusses a comparison between the Corfou code and other models which are being currently developed [fr

Comparison of typical inelastic analysis predictions with benchmark problem experimental results

International Nuclear Information System (INIS)

Clinard, J.A.; Corum, J.M.; Sartory, W.K.

1975-01-01

The results of exemplary inelastic analyses for experimental benchmark problems on reactor components are presented. Consistent analytical procedures and constitutive relations were used in each of the analyses, and the material behavior data presented in the Appendix were used in all cases. Two finite-element inelastic computer programs were employed. These programs implement the analysis procedures and constitutive equations for type 304 stainless steel that are currently used in many analyses of elevated-temperature nuclear reactor system components. The analysis procedures and constitutive relations are briefly discussed, and representative analytical results are presented and compared to the test data. The results that are presented demonstrate the feasibility of performing inelastic analyses for the types of problems discussed, and they are indicative of the general level of agreement that the analyst might expect when using conventional inelastic analysis procedures. (U.S.)

Sensitivity Analysis of Different Shapes of a Plastic Optical Fiber-Based Immunosensor for Escherichia coli: Simulation and Experimental Results.

Science.gov (United States)

Rodrigues, Domingos M C; Lopes, Rafaela N; Franco, Marcos A R; Werneck, Marcelo M; Allil, Regina C S B

2017-12-19

Conventional pathogen detection methods require trained personnel, specialized laboratories and can take days to provide a result. Thus, portable biosensors with rapid detection response are vital for the current needs for in-loco quality assays. In this work the authors analyze the characteristics of an immunosensor based on the evanescent field in plastic optical fibers with macro curvature by comparing experimental with simulated results. The work studies different shapes of evanescent-wave based fiber optic sensors, adopting a computational modeling to evaluate the probes with the best sensitivity. The simulation showed that for a U-Shaped sensor, the best results can be achieved with a sensor of 980 µm diameter by 5.0 mm in curvature for refractive index sensing, whereas the meander-shaped sensor with 250 μm in diameter with radius of curvature of 1.5 mm, showed better sensitivity for either bacteria and refractive index (RI) sensing. Then, an immunosensor was developed, firstly to measure refractive index and after that, functionalized to detect Escherichia coli . Based on the results with the simulation, we conducted studies with a real sensor for RI measurements and for Escherichia coli detection aiming to establish the best diameter and curvature radius in order to obtain an optimized sensor. On comparing the experimental results with predictions made from the modelling, good agreements were obtained. The simulations performed allowed the evaluation of new geometric configurations of biosensors that can be easily constructed and that promise improved sensitivity.

Sensitivity Analysis of Different Shapes of a Plastic Optical Fiber-Based Immunosensor for Escherichia coli: Simulation and Experimental Results

Directory of Open Access Journals (Sweden)

Domingos M. C. Rodrigues

2017-12-01

Full Text Available Conventional pathogen detection methods require trained personnel, specialized laboratories and can take days to provide a result. Thus, portable biosensors with rapid detection response are vital for the current needs for in-loco quality assays. In this work the authors analyze the characteristics of an immunosensor based on the evanescent field in plastic optical fibers with macro curvature by comparing experimental with simulated results. The work studies different shapes of evanescent-wave based fiber optic sensors, adopting a computational modeling to evaluate the probes with the best sensitivity. The simulation showed that for a U-Shaped sensor, the best results can be achieved with a sensor of 980 µm diameter by 5.0 mm in curvature for refractive index sensing, whereas the meander-shaped sensor with 250 μm in diameter with radius of curvature of 1.5 mm, showed better sensitivity for either bacteria and refractive index (RI sensing. Then, an immunosensor was developed, firstly to measure refractive index and after that, functionalized to detect Escherichia coli. Based on the results with the simulation, we conducted studies with a real sensor for RI measurements and for Escherichia coli detection aiming to establish the best diameter and curvature radius in order to obtain an optimized sensor. On comparing the experimental results with predictions made from the modelling, good agreements were obtained. The simulations performed allowed the evaluation of new geometric configurations of biosensors that can be easily constructed and that promise improved sensitivity.

Experimental implementation of a low-frequency global sound equalization method based on free field propagation

DEFF Research Database (Denmark)

Santillan, Arturo Orozco; Pedersen, Christian Sejer; Lydolf, Morten

2007-01-01

An experimental implementation of a global sound equalization method in a rectangular room using active control is described in this paper. The main purpose of the work has been to provide experimental evidence that sound can be equalized in a continuous three-dimensional region, the listening zone......, which occupies a considerable part of the complete volume of the room. The equalization method, based on the simulation of a progressive plane wave, was implemented in a room with inner dimensions of 2.70 m x 2.74 m x 2.40 m. With this method,the sound was reproduced by a matrix of 4 x 5 loudspeakers...... in one of the walls. After traveling through the room, the sound wave was absorbed on the opposite wall, which had a similar arrangement of loudspeakers, by means of active control. A set of 40 digital FIR filters was used to modify the original input signal before it was fed to the loudspeakers, one...

Experimental design and multicriteria decision making methods for the optimization of ice cream composition

Directory of Open Access Journals (Sweden)

Cristian Rojas

2012-03-01

Full Text Available The aim of the present work was to optimize the sensorial and technological features of ice cream. The experimental work was performed in two stages: 1 optimization of lactose enzymatic hydrolysis, and 2 optimization of the process and product. For the first stage a complete factorial design was developed, optimized using both response surface and the steepest ascent method. In the second stage a mixture design was performed, combining the process variables. The product with the best sensorial acceptance, high yield and low cost was selected. The acceptance of the product was developed by an untrained taster’s panel. As a main result the sensorial and technological features of the final product were improved, establishing the optimum parameters for its elaboration.

Experimental methods in natural convection

International Nuclear Information System (INIS)

Koster, J.N.

1982-11-01

Some common experimental techniques to determine local velocities and to visualize temperature fields in natural convection research are discussed. First the physics and practice of anemometers are discussed with emphasis put on optical anemometers. In the second and third case the physics and practice of the most developed interferometers are discussed; namely differential interferometry for visualization of temperature gradient fields and holographic interferometry for visualization of temperature fields. At the Institut fuer Reaktorbauelemente these three measuring techniques are applied for convection and pipe flow studies. (orig.) [de

Blanking and piercing theory, applications and recent experimental results

International Nuclear Information System (INIS)

Zaid, Adnan l O

2014-01-01

Blanking and piercing are manufacturing processes by which certain geometrical shapes are sheared off a sheet metal. If the sheared off part is the one required, the processes referred to as blanking and if the remaining part in the sheet is the one required, the process is referred to as piercing. In this paper, the theory and practice of these processes are reviewed and discussed The main parameters affecting these processes are presented and discussed. These include: the radial clearance percentage, punch and die geometrical parameters, for example punch and die profile radii. The abovementioned parameters on the force and energy required to effect blanking together with their effect on the quality of the products are also presented and discussed. Recent experimental results together with photomacrographs and photomicrographs are also included and discussed. Finally, the effect of punch and die wear on the quality of the blanks is alsogiven and discussed

Non-linear thermal analysis of light concrete hollow brick walls by the finite element method and experimental validation

International Nuclear Information System (INIS)

Diaz del Coz, J.J.; Nieto, P.J. Garcia; Rodriguez, A. Martin; Martinez-Luengas, A. Lozano; Biempica, C. Betegon

2006-01-01

The finite element method (FEM) is applied to the non-linear complex heat transfer analysis of light concrete hollow brick walls. The non-linearity is due to the radiation boundary condition inside the inner holes of the bricks. The conduction and convection phenomena are taking into account in this study for three different values of the conductivity mortar and two values for the brick. Finally, the numerical and experimental results are compared and a good agreement is shown

Non-linear thermal analysis of light concrete hollow brick walls by the finite element method and experimental validation

Energy Technology Data Exchange (ETDEWEB)

Del Coz Diaz, J.J.; Rodriguez, A. Martin; Martinez-Luengas, A. Lozano; Biempica, C. Betegon [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain); Nieto, P.J. Garcia [Departamento de Matematicas, Facultad de Ciencias, C/Calvo Sotelo s/n, 33007 Oviedo, Asturias (Spain)

2006-06-15

The finite element method (FEM) is applied to the non-linear complex heat transfer analysis of light concrete hollow brick walls. The non-linearity is due to the radiation boundary condition inside the inner holes of the bricks. The conduction and convection phenomena are taking into account in this study for three different values of the conductivity mortar and two values for the brick. Finally, the numerical and experimental results are compared and a good agreement is shown. [Author].

Non-linear thermal analysis of light concrete hollow brick walls by the finite element method and experimental validation

Energy Technology Data Exchange (ETDEWEB)

Diaz del Coz, J.J. [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain)]. E-mail: juanjo@constru.uniovi.es; Nieto, P.J. Garcia [Departamento de Matematicas, Facultad de Ciencias, C/Calvo Sotelo s/n, 33007 Oviedo, Asturias (Spain); Rodriguez, A. Martin [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain); Martinez-Luengas, A. Lozano [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain); Biempica, C. Betegon [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain)

2006-06-15

The finite element method (FEM) is applied to the non-linear complex heat transfer analysis of light concrete hollow brick walls. The non-linearity is due to the radiation boundary condition inside the inner holes of the bricks. The conduction and convection phenomena are taking into account in this study for three different values of the conductivity mortar and two values for the brick. Finally, the numerical and experimental results are compared and a good agreement is shown.

The Trojan Horse method for nuclear astrophysics: Recent results on resonance reactions

Energy Technology Data Exchange (ETDEWEB)

Cognata, M. La; Pizzone, R. G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Spitaleri, C.; Cherubini, S.; Romano, S. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania, Italy and Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Gulino, M.; Tumino, A. [Kore University, Enna, Italy and Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Lamia, L. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy)

2014-05-09

Nuclear astrophysics aims to measure nuclear-reaction cross sections of astrophysical interest to be included into models to study stellar evolution and nucleosynthesis. Low energies, < 1 MeV or even < 10 keV, are requested for this is the window where these processes are more effective. Two effects have prevented to achieve a satisfactory knowledge of the relevant nuclear processes, namely, the Coulomb barrier exponentially suppressing the cross section and the presence of atomic electrons. These difficulties have triggered theoretical and experimental investigations to extend our knowledge down to astrophysical energies. For instance, indirect techniques such as the Trojan Horse Method have been devised yielding new cutting-edge results. In particular, I will focus on the application of this indirect method to resonance reactions. Resonances might dramatically enhance the astrophysical S(E)-factor so, when they occur right at astrophysical energies, their measurement is crucial to pin down the astrophysical scenario. Unknown or unpredicted resonances might introduce large systematic errors in nucleosynthesis models. These considerations apply to low-energy resonances and to sub-threshold resonances as well, as they may produce sizable modifications of the S-factor due to, for instance, destructive interference with another resonance.

The Trojan Horse method for nuclear astrophysics: Recent results on resonance reactions

International Nuclear Information System (INIS)

Cognata, M. La; Pizzone, R. G.; Spitaleri, C.; Cherubini, S.; Romano, S.; Gulino, M.; Tumino, A.; Lamia, L.

2014-01-01

Nuclear astrophysics aims to measure nuclear-reaction cross sections of astrophysical interest to be included into models to study stellar evolution and nucleosynthesis. Low energies, < 1 MeV or even < 10 keV, are requested for this is the window where these processes are more effective. Two effects have prevented to achieve a satisfactory knowledge of the relevant nuclear processes, namely, the Coulomb barrier exponentially suppressing the cross section and the presence of atomic electrons. These difficulties have triggered theoretical and experimental investigations to extend our knowledge down to astrophysical energies. For instance, indirect techniques such as the Trojan Horse Method have been devised yielding new cutting-edge results. In particular, I will focus on the application of this indirect method to resonance reactions. Resonances might dramatically enhance the astrophysical S(E)-factor so, when they occur right at astrophysical energies, their measurement is crucial to pin down the astrophysical scenario. Unknown or unpredicted resonances might introduce large systematic errors in nucleosynthesis models. These considerations apply to low-energy resonances and to sub-threshold resonances as well, as they may produce sizable modifications of the S-factor due to, for instance, destructive interference with another resonance

A global analysis of recent experimental results: How well determined are the parton distribution functions?

International Nuclear Information System (INIS)

Morfin, J.G.

1990-08-01

Following is a brief summary of the results of an analysis of experimental data performed to extract the patron distribution functions. In contrast to other global analyses, this study investigated how the fit results depend on: Experimental Systematic Errors; Kinematic Cuts on the Analyzed Data and Choice of Initial Functional Forms, with a prime goal being a close look at the range of low-x behavior allowed by data. This is crucial for predictions for the SSC/LHC, HERA, and even at Tevatron Collider energies. Since all details can be found in the just released Fermilab preprint Parton Distributions from a Global QCD Analysis of Deep Inelastic Scattering and Lepton-Pair Production by J. G. M. and Wu-Ki Tung, this summary will be only a brief outline of major results. 11 refs., 13 figs

Stacking interactions between carbohydrate and protein quantified by combination of theoretical and experimental methods.

Directory of Open Access Journals (Sweden)

Michaela Wimmerová

Full Text Available Carbohydrate-receptor interactions are an integral part of biological events. They play an important role in many cellular processes, such as cell-cell adhesion, cell differentiation and in-cell signaling. Carbohydrates can interact with a receptor by using several types of intermolecular interactions. One of the most important is the interaction of a carbohydrate's apolar part with aromatic amino acid residues, known as dispersion interaction or CH/π interaction. In the study presented here, we attempted for the first time to quantify how the CH/π interaction contributes to a more general carbohydrate-protein interaction. We used a combined experimental approach, creating single and double point mutants with high level computational methods, and applied both to Ralstonia solanacearum (RSL lectin complexes with α-L-Me-fucoside. Experimentally measured binding affinities were compared with computed carbohydrate-aromatic amino acid residue interaction energies. Experimental binding affinities for the RSL wild type, phenylalanine and alanine mutants were -8.5, -7.1 and -4.1 kcal x mol(-1, respectively. These affinities agree with the computed dispersion interaction energy between carbohydrate and aromatic amino acid residues for RSL wild type and phenylalanine, with values -8.8, -7.9 kcal x mol(-1, excluding the alanine mutant where the interaction energy was -0.9 kcal x mol(-1. Molecular dynamics simulations show that discrepancy can be caused by creation of a new hydrogen bond between the α-L-Me-fucoside and RSL. Observed results suggest that in this and similar cases the carbohydrate-receptor interaction can be driven mainly by a dispersion interaction.

An experimental method to verify soil conservation by check dams on the Loess Plateau, China.

Science.gov (United States)

Xu, X Z; Zhang, H W; Wang, G Q; Chen, S C; Dang, W Q

2009-12-01

A successful experiment with a physical model requires necessary conditions of similarity. This study presents an experimental method with a semi-scale physical model. The model is used to monitor and verify soil conservation by check dams in a small watershed on the Loess Plateau of China. During experiments, the model-prototype ratio of geomorphic variables was kept constant under each rainfall event. Consequently, experimental data are available for verification of soil erosion processes in the field and for predicting soil loss in a model watershed with check dams. Thus, it can predict the amount of soil loss in a catchment. This study also mentions four criteria: similarities of watershed geometry, grain size and bare land, Froude number (Fr) for rainfall event, and soil erosion in downscaled models. The efficacy of the proposed method was confirmed using these criteria in two different downscaled model experiments. The B-Model, a large scale model, simulates watershed prototype. The two small scale models, D(a) and D(b), have different erosion rates, but are the same size. These two models simulate hydraulic processes in the B-Model. Experiment results show that while soil loss in the small scale models was converted by multiplying the soil loss scale number, it was very close to that of the B-Model. Obviously, with a semi-scale physical model, experiments are available to verify and predict soil loss in a small watershed area with check dam system on the Loess Plateau, China.

Experimental results for hydrocarbon refrigerant vaporization inside brazed plate heat exchangers at high pressure

DEFF Research Database (Denmark)

Desideri, Adriano; Ommen, Torben Schmidt; Wronski, Jorrit

2016-01-01

fluids at typical working conditions of ORC systems for low temperature waste heat recovery (WHR) applications. Based on these premises, a novel testrig has been recently designed and built at the Technical University of Denmark to simulate the evaporating condition occurring in a small capacity ORC...... power unit. In this contribution the preliminary experimental results obtained from the first experimental campaign carried out on the rig are reported. HFC-134a was selected as working fluid. The experiments were carried out at saturation temperature of 60, 70 and 80 °C and inlet and outlet qualities...

Photoelectrochemical water splitting standards, experimental methods, and protocols

CERN Document Server

Chen, Zhebo; Miller, Eric

2014-01-01

This book outlines many of the techniques involved in materials development and characterization for photoelectrochemical (PEC) - for example, proper metrics for describing material performance, how to assemble testing cells and prepare materials for assessment of their properties, and how to perform the experimental measurements needed to achieve reliable results towards better scientific understanding. For each technique, proper procedure, benefits, limitations, and data interpretation are discussed. Consolidating this information in a short, accessible, and easy to read reference guide will allow researchers to more rapidly immerse themselves into PEC research and also better compare their results against those of other researchers to better advance materials development. This book serves as a "how-to" guide for researchers engaged in or interested in engaging in the field of photoelectrochemical (PEC) water splitting. PEC water splitting is a rapidly growing field of research in which the goal is to deve...

Book Review "Cambridge handbook of experimental political science"

NARCIS (Netherlands)

Grimmelikhuijsen, Stephan

2014-01-01

Experimentation has formed the basis for modern scientific discovery. Francis Bacon (1561– 1626), “the father of empiricism,” was one of the first to propose a method of science based on experimentation that results in new theories that can again be tested by experimentation. At first, experiments

A comparison of two methods for prediction of response and rates of inbreeding in selected populations with the results obtained in two selection experiments

Directory of Open Access Journals (Sweden)

Verrier Etienne

2005-05-01

Full Text Available Abstract Selection programmes are mainly concerned with increasing genetic gain. However, short-term progress should not be obtained at the expense of the within-population genetic variability. Different prediction models for the evolution within a small population of the genetic mean of a selected trait, its genetic variance and its inbreeding have been developed but have mainly been validated through Monte Carlo simulation studies. The purpose of this study was to compare theoretical predictions to experimental results. Two deterministic methods were considered, both grounded on a polygenic additive model. Differences between theoretical predictions and experimental results arise from differences between the true and the assumed genetic model, and from mathematical simplifications applied in the prediction methods. Two sets of experimental lines of chickens were used in this study: the Dutch lines undergoing true truncation mass selection, the other lines (French undergoing mass selection with a restriction on the representation of the different families. This study confirmed, on an experimental basis, that modelling is an efficient approach to make useful predictions of the evolution of selected populations although the basic assumptions considered in the models (polygenic additive model, normality of the distribution, base population at the equilibrium, etc. are not met in reality. The two deterministic methods compared yielded results that were close to those observed in real data, especially when the selection scheme followed the rules of strict mass selection: for instance, both predictions overestimated the genetic gain in the French experiment, whereas both predictions were close to the observed values in the Dutch experiment.

Main Experimental Results of ISTC-1606 for Recycling and Transmutation in Molten Salt Systems

Energy Technology Data Exchange (ETDEWEB)

Ignatiev, Victor; Feynberg, Olga; Merzlyakov, Aleksandr; Surenkov, Aleksandr [Russian Research Center - Kurchatov Institute, Kurchatov sq. 1, Moscow, RF, 123182 (Russian Federation); Subbotin, Vladimir; Zakirov, Raul; Toropov, Andrey; Panov, Aleksandr [Russian Federal Nuclear Center - Institute of Technical Physics, Snezhinsk (Russian Federation); Afonichkin, Valery [Institute of High-Temperature Electrochemistry, Ekaterinburg (Russian Federation)

2008-07-01

To examine and demonstrate the feasibility of molten salt reactors (MSR) to reduce long lived waste toxicity and to produce efficiently electricity in closed fuel cycle, some national and international studies were initiated last years. In this paper main focus is placed on experimental evaluation of single stream Molten Salt Actinide Recycler and Transmuter (MOSART) system fuelled with different compositions of plutonium plus minor actinide trifluoride (AnF{sub 3}) from LWR spent nuclear fuel without U-Th support. This paper summarizes main experimental results of ISTC-1606 related to physical and chemical properties of fuel salt, container materials for fuel circuit, and fuel salt clean up of MOSART system. As result of ISTC-1606 studies claim is made, that the {sup 7}Li,Na,Be/F and {sup 7}Li,Be/F solvents selected for primary system appear to resolve main reactor physics, thermal hydraulics, materials compatibility, fuel salt clean up and safety problems as applied to the MOSART concept development. The created experimental facilities and the database on properties of fuel salt mixtures and container materials are used for a choice and improvement fuel salts and coolants for new applications of this high temperature technology for sustainable nuclear power development. (authors)

Main Experimental Results of ISTC-1606 for Recycling and Transmutation in Molten Salt Systems

International Nuclear Information System (INIS)

Ignatiev, Victor; Feynberg, Olga; Merzlyakov, Aleksandr; Surenkov, Aleksandr; Subbotin, Vladimir; Zakirov, Raul; Toropov, Andrey; Panov, Aleksandr; Afonichkin, Valery

2008-01-01

To examine and demonstrate the feasibility of molten salt reactors (MSR) to reduce long lived waste toxicity and to produce efficiently electricity in closed fuel cycle, some national and international studies were initiated last years. In this paper main focus is placed on experimental evaluation of single stream Molten Salt Actinide Recycler and Transmuter (MOSART) system fuelled with different compositions of plutonium plus minor actinide trifluoride (AnF 3 ) from LWR spent nuclear fuel without U-Th support. This paper summarizes main experimental results of ISTC-1606 related to physical and chemical properties of fuel salt, container materials for fuel circuit, and fuel salt clean up of MOSART system. As result of ISTC-1606 studies claim is made, that the 7 Li,Na,Be/F and 7 Li,Be/F solvents selected for primary system appear to resolve main reactor physics, thermal hydraulics, materials compatibility, fuel salt clean up and safety problems as applied to the MOSART concept development. The created experimental facilities and the database on properties of fuel salt mixtures and container materials are used for a choice and improvement fuel salts and coolants for new applications of this high temperature technology for sustainable nuclear power development. (authors)

EXPERIMENTAL TESTING OF DRAW—BEAD RESTRAINING FORCE IN SHEET METAL FORMING

Institute of Scientific and Technical Information of China (English)

J.H.Yang; J.Chen; 等

2003-01-01

Due to complexities of draw-bead restraining force calculated according to theory and depending on sheet metal forming properties experiment testing system,a simplified method to calculate draw-bead restraining force is put forward by experimental method in cup-shaped drawing process.The experimental results were compared with numer-ical results and proved agreement.It shows the method is effective.

Experimental Quasi-Microwave Whole-Body Averaged SAR Estimation Method Using Cylindrical-External Field Scanning

OpenAIRE

Kawamura, Yoshifumi; Hikage, Takashi; Nojima, Toshio

2010-01-01

The aim of this study is to develop a new whole-body averaged specific absorption rate (SAR) estimation method based on the external-cylindrical field scanning technique. This technique is adopted with the goal of simplifying the dosimetry estimation of human phantoms that have different postures or sizes. An experimental scaled model system is constructed. In order to examine the validity of the proposed method for realistic human models, we discuss the pros and cons of measurements and nume...

EXPERIMENTAL VALIDATION FOR THE TRAINING METHOD AND MATHEMATICAL MODEL OF THE PILOT SKILL FORMATION IN MAINTENANCE OF ATTITUDE ORIENTATION

Directory of Open Access Journals (Sweden)

Maksim BARABANOV

2017-12-01

Full Text Available In order to overcome the drawbacks in artificial horizon indicator (HI of inside-in type (a view from an aircraft (A/C, where pilots produce mistakes in maintenance of attitude orientation most of all, the authors offer a novel training method. The method is based on the hypothesis that the manipulative ability of a human visual system can be trained. A mathematical model for the data accumulation during the corresponding training procedure has been proposed. Construction, design and results of the model evaluation are presented in the article. The experimental results revealed the increase of the probability of faultless operation by the test group of up to 0,892, whereas the faultless operation probability of a control group was 0,726. Thus, the trainee-students have statistically increased the reliability for the maintenance of attitude orientation thanks to the proposed method, and the hypothesis was confirmed.

Deviations between experimental and theoretical results in Ar (e, 3e) double ionization

International Nuclear Information System (INIS)

Jia, C C; Lahmam-Bennani, A; Cappello, C Dal; Duguet, A; Avaldi, L

2003-01-01

The coplanar (e, 3e) relative cross sections for double ionization of argon have been measured at an electron impact energy of E 0 = 561.4 eV and under equal energy sharing among the two 'ejected' electrons, E b = E c = 9 eV. The scattering angle is fixed to θ a = 1.5 degrees, corresponding to a momentum transfer K=0.4 au to the target. The experimental results have been compared with calculations in the first Born approximation, which include only first-order processes in the target-projectile interaction. The comparison shows severe deviations between the experimental and theoretical results. These deviations are much larger than the ones previously observed in helium under comparable kinematics. To fill this gap between theory and experiment, a decisive improvement in the theory is needed. This can be achieved by improving the first-order calculations and by including higher-order processes such as the two-step mechanism, or even new mechanisms, for instance the simultaneous ejection of the pair of target electrons. (letter to the editor)

Thermal conductivity of silicic tuffs: predictive formalism and comparison with preliminary experimental results

International Nuclear Information System (INIS)

Lappin, A. R.

1980-07-01

Performance of both near- and far-field thermomechanical calculations to assess the feasibility of waste disposal in silicic tuffs requires a formalism for predicting thermal conductivity of a broad range of tuffs. This report summarizes the available thermal conductivity data for silicate phases that occur in tuffs and describes several grain-density and conductivity trends which may be expected to result from post-emplacement alteration. A bounding curve is drawn that predicts the minimum theoretical matrix (zero-porosity) conductivity for most tuffs as a function of grain density. Comparison of experimental results with this curve shows that experimental conductivities are consistently lower at any given grain density. Use of the lowered bounding curve and an effective gas conductivity of 0.12 W/m 0 C allows conservative prediction of conductivity for a broad range of tuff types. For the samples measured here, use of the predictive curve allows estimation of conductivity to within 15% or better, with one exception. Application and possible improvement of the formalism are also discussed

Use of the dynamic stiffness method to interpret experimental data from a nonlinear system

Science.gov (United States)

Tang, Bin; Brennan, M. J.; Gatti, G.

2018-05-01

The interpretation of experimental data from nonlinear structures is challenging, primarily because of dependency on types and levels of excitation, and coupling issues with test equipment. In this paper, the use of the dynamic stiffness method, which is commonly used in the analysis of linear systems, is used to interpret the data from a vibration test of a controllable compressed beam structure coupled to a test shaker. For a single mode of the system, this method facilitates the separation of mass, stiffness and damping effects, including nonlinear stiffness effects. It also allows the separation of the dynamics of the shaker from the structure under test. The approach needs to be used with care, and is only suitable if the nonlinear system has a response that is predominantly at the excitation frequency. For the structure under test, the raw experimental data revealed little about the underlying causes of the dynamic behaviour. However, the dynamic stiffness approach allowed the effects due to the nonlinear stiffness to be easily determined.

Simplified analytical methods and experimental correlations of damping in piping during dynamic high-level inelastic response

International Nuclear Information System (INIS)

Severud, L.K.

1987-01-01

Simplified methods for predicting equivalent viscous damping are used to assess damping contributions due to piping inelastic plastic hinge action and support snubbers. These increments are compared to experimental findings from shake and snap-back tests of several pipe systems. Good correlations were found confirming the usefulness of the simplified methods

Blanking and piercing theory, applications and recent experimental results

International Nuclear Information System (INIS)

Zaid, A. I. O.

2013-01-01

Blanking and piercing are manufacturing processes by which certain geometrical shapes are sheared off a sheet metal. If the sheared off part is the one required, the processes referred to as blanking and if the remaining part in the sheet is the one required, the process is referred to as piercing. In this paper, the theory and practice of these processes are reviewed and discussed The main parameters affecting these processes are presented and discussed. These include: the radial clearance percentage, punch and die geometrical parameters, for example punch and die profile radii. The above mentioned parameters on the force and energy required to effect blanking together with their effect on the quality of the products are also presented and discussed. Recent experimental results together with photomacrographs and photomicrographs are also included and discussed. Finally, the effect of punch and die wear on the quality of the blanks is also given and discussed. (author)

New particles: experimental results

International Nuclear Information System (INIS)

Augustin, J.E.

The results of studies on production and properties of psi(3100) and psi(3700) resonances are presented, particular attention being given to spin, parity, g-parity and isospin determination. Evidence obtained in the SPEAR and DORIS storage rings in psi'→γ chi and psi→γX intermediate states are presented, together with SPEAR results on e-μ events and high energy jet production. (39 references) [fr

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

Experimental research on charging characteristics of a solar photovoltaic system by the pressure-control method

Institute of Scientific and Technical Information of China (English)

Hua ZHU; Zhang-lu XU; Zi-juan CAO

2011-01-01

The charging characteristics of the valve-regulated lead acid (VRLA) battery driven by solar energy were experimentally studied through the pressure-control method in this paper. The aims of the research were to increase charging efficiency to make the most of solar energy and to improve charging quality to prolong life of battery. The charging process of a 12 V 12 A.h VRLA battery has been tested under the mode of a stand-alone photovoltaic (PV) system. Results show that the pressure-control method can effectively control PV charging of the VRLA battery and make the best of PV cells through the maximum power point tracking (MPPT). The damage of VRLA battery by excess oxygen accumulation can be avoided through the inner pressure control of VRLA battery. Parameters such as solar radiation intensity, charging power, inner pressure of the battery, and charging current and voltage during the charging process were measured and analyzed.

Experimental results on 2-30 keV bremsstrahlung from thick and thin targets

Energy Technology Data Exchange (ETDEWEB)

Shanker, R. [Atomic Physics Laboratory, Physics Department, Banaras Hindu University, Varanasi 221005 (India)]. E-mail: rshanker@bhu.ac.in

2006-10-15

The recent experimental investigations on electron bremsstrahlung produced from impact of 2-30 keV electrons with thick solid and thin gaseous targets are reviewed. The theoretical models describing the energy and angular distributions of bremsstrahlung photons are discussed with their brief outlines and formulations to explain the experimental data. The results on thick target bremsstrahlung (TTB) spectra produced by keV electrons have suggested that there is a need to develop a comprehensive theory for accounting the solid state effects. It is further noted that the prediction of the modified KKD formula gives a reasonable agreement with the TTB data, whereas a semi-empirical formula gives a better fit to the data for thick targets. The available experimental data for dependence of double differential cross-sections of emitted photons on impact energy and their emission angles for gaseous atoms and molecules exhibit a good agreement with the theoretical calculations of Kissel et al., [1983. Shape functions for atomic-field bremsstrahlung from electrons of kinetic energy 1-500 keV on selected neutral atoms 1

Experimental results from a pilot plant for the ammonia removal from drinkable supply

International Nuclear Information System (INIS)

Bruno, G.; Di Sabatino, B.

2001-01-01

Ion exchange represents a valid alternative to chlorination for ammonia removal from drinking water, because it allows to prevent the main disadvantage of the chlorination process, i.e. the production of chlorinated organic compounds, which may be cancerous, occurring when the water to be treated contains organic substances. Ion exchange can be carried out by means of natural zeolites. Zeolites are microcrystalline aluminosilicates minerals, being common constituents of the quaternary tuffs emitted by volcanic alkaline - potassic districts of Lazio (Italy). Particularly, phyllipsite and chabasite were selected among several zeolites species because of their high specific selectivity with ammonium ion and high theoretical exchange capacity (3.5 meq/g). The concentrations of such mineral in the rocks employed were about 40-50%. A preliminary experimental step was performed in order to select the main operative parameters. Then, a pilot plant was built up at the 'Acquedotto Municipale' of Turin (Italy), made by filtration columns. A nitrifying biomass was observed to grow onto the zeolite granules, thus forming a combined chemical-biological system allowing a high removal efficiency to be attained throughout the experimental campaigns. The present paper deals with the results obtained from a two-year experimental investigation [it

An experimental method for designing the municipal solid waste biodrying

International Nuclear Information System (INIS)

Rada, E.C.; Politecnico Univ., Bucarest; Franzinelli, A.; Taiss, M.; Ragazzi, M.; Panaitescu, V.; Apostol, T.

2005-01-01

In the management of Municipal Solid Waste (MSW), in agreement with the new European directives concerning the valorization of materials and energy recovery, a recent approach based on a one-stream Biological Mechanical Treatment (BMT) is spreading as an alternative to the traditional two-stream approach. The bio-mechanical treatment of MSW is an increasing option either as a pre-treatment before land filling or as a pre-treatment before combustion. In the present paper an experimental method for designing the Municipal Solid Waste bio-drying is proposed. That means this paper deals with the option of energy recovery. The aim is to provide design criteria for bio-drying plants independent from the patents available in the sector [it

A review of experimental methods for determining residual creep life

International Nuclear Information System (INIS)

Bolton, C.J.

1977-11-01

Experimental methods available for determining how much creep life remains at a particular time in the high temperature service of a component are reviewed. After a brief consideration of the limitations of stress rupture extrapolation techniques, the application of post-exposure creep testing is considered. Ways of assessing the effect of microstructural degradation on residual life are then reviewed. It is pointed out that while this type of work will be useful for certain materials, there are other materials in which 'mechanical damage' such as cavitation will be more important. Cavitation measurement techniques are therefore reviewed. The report ends with a brief consideration of the use of crack growth measurements in assessing the residual life of cracked components. (author)

Comparison of numerical results with experimental data for single-phase natural convection in an experimental sodium loop. [LMFBR

Energy Technology Data Exchange (ETDEWEB)

Ribando, R.J.

1979-01-01

A comparison is made between computed results and experimental data for a single-phase natural convection test in an experimental sodium loop. The test was conducted in the Thermal-Hydraulic Out-of-Reactor Safety (THORS) facility, an engineering-scale high temperature sodium loop at the Oak Ridge National Laboratory (ORNL) used for thermal-hydraulic testing of simulated Liquid Metal Fast Breeder Reactor (LMFBR) subassemblies at normal and off-normal operating conditions. Heat generation in the 19 pin assembly during the test was typical of decay heat levels. The test chosen for analysis in this paper was one of seven natural convection runs conducted in the facility using a variety of initial conditions and testing parameters. Specifically, in this test the bypass line was open to simulate a parallel heated assembly and the test was begun with a pump coastdown from a small initial forced flow. The computer program used to analyze the test, LONAC (LOw flow and NAtural Convection) is an ORNL-developed, fast-running, one-dimensional, single-phase, finite-difference model used for simulating forced and free convection transients in the THORS loop.

First results of Minimum Fisher Regularisation as unfolding method for JET NE213 liquid scintillator neutron spectrometry

International Nuclear Information System (INIS)

Mlynar, Jan; Adams, John M.; Bertalot, Luciano; Conroy, Sean

2005-01-01

At JET, the NE213 liquid scintillator is being validated as a diagnostic tool for spectral measurements of neutrons emitted from the plasma. Neutron spectra have to be unfolded from the measured pulse-height spectra, which is an ill-conditioned problem. Therefore, use of two independent unfolding methods allows for less ambiguity on the interpretation of the data. In parallel to the routine algorithm MAXED based on the Maximum Entropy method, the Minimum Fisher Regularisation (MFR) method has been introduced at JET. The MFR method, known from two-dimensional tomography applications, has proved to provide a new transparent tool to validate the JET neutron spectra measured with the NE213 liquid scintillators. In this article, the MFR method applicable to spectra unfolding is briefly explained. After a mention of MFR tests on phantom spectra experimental neutron spectra are presented that were obtained by applying MFR to NE213 data in selected JET experiments. The results tend to confirm MAXED observations

New dynamics information from experimental results obtained in d-Au collisions at RHIC-BNL energies

International Nuclear Information System (INIS)

Jipa, Alexandru

2004-01-01

During the last runs d-Au collisions at √s NN = 200 GeV have been investigated at RHIC-BNL using the BRAHMS Experiment. Some interesting experimental results on charged particle multiplicities, rapidity distributions, transverse momentum spectra, antiparticle to particle ratios, participant spectator evolution have been obtained. In this work the most interesting results are presented for different rapidity and collision centrality ranges. Taking into account the importance of the collision geometry and collision symmetry in the collision dynamics, comparisons with the similar experimental results obtained in Au-Au collisions have been done. New interesting results can be reported. The most significant are related to the evolution of the nuclear modification factor with rapidity and collision centrality. The high transverse momentum suppression and the behaviours in different rapidity and centrality ranges suggest strong initial state effects. These effects could be related to the gluonic structure of the colliding nuclei. Some insights on the Color Glass Condensate formation are possible. (author)

El método científico experimental en las clases de laboratorio de física / The experimental scientific method in Physics laboratory lessons

Directory of Open Access Journals (Sweden)

Landa, L. C.

2016-12-01

Full Text Available En el presente estudio los autores abordan la aplicación del método científico experimental en el proceso de enseñanza de la Física como parte del modelo de aprendizaje como investigación en la carrera de Matemática-Física. El análisis de diferentes resultados investigativos publicados en la última década posibilitó identificar avances significativos en este campo, sobre todo en cuanto a la operacionalización del método y la utilización de simulaciones y experimentos virtuales en la enseñanza de la Física, sin embargo, aún persisten insuficiencias en el proceder de los docentes que limitan la apropiación del método por parte de los estudiantes. En particular, se ofrece a los docentes una alternativa metodológica para la introducción del método científico experimental, en las prácticas de laboratorio de Física, que contribuye al tránsito de los estudiantes por los procedimientos del citado método. Finalmente se expone un ejemplo concreto del modo en que se aplicó la alternativa metodológica en una clase de laboratorio de Física. This article deals with the application of the experimental scientific method in the teaching and learning process in Mathematics-Physics career as a part of learning by researching model. The study of references and the analysis of former research findings allow identifying significant achievements in the last ten years, mainly about the application of the method and also the use of virtual experiments and simulation in teaching Physics. However, there are several shortcomings of procedural nature that hinder the students’ appropriation of the method. The main finding is a proposal of a teaching alternative to achieve the learning of the experimental scientific method and its procedures by the students. Finally, that teaching alternative is illustrated in a particular Physics laboratory lesson

Conservatism of loss-of-coolant accident licensing analysis compared to experimental results and best-estimate calculation

International Nuclear Information System (INIS)

Winkler, F.; Friedmann, P.

1986-01-01

The paper compares results of loss-of-coolant accident licensing analysis with experimental results and results of best-estimate calculations. The large safety margins resulting from the more realistic best-estimate results are used to show the high conservatism inherent in the licensing process of pressurized water reactors. (orig.) [de

Experimental Study on Solar Cooling Tube Using Thermal/Vacuum Emptying Method

Directory of Open Access Journals (Sweden)

Huizhong Zhao

2012-01-01

Full Text Available A solar cooling tube using thermal/vacuum emptying method was experimentally studied in this paper. The coefficient of performance (COP of the solar cooling tube was mostly affected by the vacuum degree of the system. In past research, the thermal vacuum method, using an electric oven and iodine-tungsten lamp to heat up the adsorbent bed and H2O vapor to expel the air from the solar cooling tube, was used to manufacture solar cooling tubes. This paper presents a novel thermal vacuum combined with vacuum pump method allowing an increased vacuum state for producing solar cooling tubes. The following conclusions are reached: the adsorbent bed temperature of solar cooling tube could reaches up to 233°C, and this temperature is sufficient to meet desorption demand; the refrigerator power of a single solar cooling tube varies from 1 W to 12 W; the total supply refrigerating capacity is about 287 kJ; and the COP of this solar cooling tube is about 0.215.

A dual tracer ratio method for comparative emission measurements in an experimental dairy housing

Science.gov (United States)

Mohn, Joachim; Zeyer, Kerstin; Keck, Margret; Keller, Markus; Zähner, Michael; Poteko, Jernej; Emmenegger, Lukas; Schrade, Sabine

2018-04-01

Agriculture, and in particular dairy farming, is an important source of ammonia (NH3) and non-carbon dioxide greenhouse gas (GHG) emissions. This calls for the development and quantification of effective mitigation strategies. Our study presents the implementation of a dual tracer ratio method in a novel experimental dairy housing with two identical, but spatially separated housing areas. Modular design and flexible floor elements allow the assessment of structural, process engineering and organisational abatement measures at practical scale. Thereby, the emission reduction potential of specific abatement measures can be quantified in relation to a reference system. Emissions in the naturally ventilated housing are determined by continuous dosing of two artificial tracers (sulphur hexafluoride SF6, trifluoromethylsulphur pentafluoride SF5CF3) and their real-time detection in the ppt range with an optimized GC-ECD method. The two tracers are dosed into different experimental sections, which enables the independent assessment of both housing areas. Mass flow emissions of NH3 and GHGs are quantified by areal dosing of tracer gases and multipoint sampling as well as real-time analysis of both tracer and target gases. Validation experiments demonstrate that the technique is suitable for both areal and point emission sources and achieves an uncertainty of less than 10% for the mass emissions of NH3, methane (CH4) and carbon dioxide (CO2), which is superior to other currently available methods. Comparative emission measurements in this experimental dairy housing will provide reliable, currently unavailable information on emissions for Swiss dairy farming and demonstrate the reduction potential of mitigation measures for NH3, GHGs and potentially other pollutants.

Experimental results on polarized structure functions in deep inelastic lepton-nucleon scattering

International Nuclear Information System (INIS)

Stuart, L.

1994-08-01

A summary is given of experimental results on spin structure functions of the proton g 1 p (x,Q 2 ), deuteron g 1 d (x,Q 2 ), and neutron g 1 n (x,Q 2 ) as measured in deep inelastic scattering of polarized leptons from a polarized target. All results are consistent with the Bjorken sum rule predictions at the Q 2 of each experiment. The data do not support the Ellis-Jaffe sum rule prediction for the proton which implies that the hencity carried by the strange quark may be nonzero and that the net quark helicity is smaller than expected from simple quark models

Study on natural convection in core barrel. Experimental and numerical results for band type spacer pads

International Nuclear Information System (INIS)

Hayashi, Kenji; Kawamata, Nobuhiro; Kamide, Hideki

2003-03-01

In a fast reactor an Inter-Wrapper Flow (IWF) is one of significant phenomena for decay heat removal under natural circulation condition, when a direct reactor auxiliary cooling system (DRACS) is adopted for decay heat removal system. Cold coolant provided by dipped heat exchangers (DHX) of DRACS can penetrate into the core barrel (region between the subassemblies) and it makes natural convection int he core barrel. Such IWF will depend on a spacer pad geometry of subassemblies. Water experiment, TRIF (Test Rig for Inter-wrapper Flow), was carried out for IWF in a reactor core. The test section modeled a 1/12th sector of the core and upper plenum of reactor vessel. Experimental parameters were the spacer pad geometry and flow path geometries connecting the upper plenum and core barrel. Numerical simulation using AQUA code was also performed to confirm applicability of a simulation method. An experimental series using a button type spacer pad had been carried out. Here a band type spacer pad was examined. Temperatures at subassembly wall were measured with parameter of the flow path geometries; one was a connection pipe between the upper plenum and core barrel and the other was flow hole in core former plates between the outermost subassemblies and the core barrel. It was found that these flow paths were effective to remove heat in the core in case of the band type spacer pad. A general purpose three dimensional analysis code, AQUA, was applied to the experimental analysis. Each subassembly and inter wrapper gap region were modeled by slab mesh geometry. Pressure loss coefficient at the pacer pad was set based on the geometry. The numerical simulation results were in good agreement with measured temperature profiles in the core. (author)

nuPRISM: An experimental method to remove neutrino interaction uncertainties from oscillation experiments

CERN Multimedia

CERN. Geneva

2014-01-01

Future experiments propose to make precision measurements of parameters in the neutrino mixing matrix, including the possibly maximal mixing angle theta23, and an unknown CP violating phase, dCP, by comparing the event rate of neutrinos and antineutrinos observed close to, and far from the source. Such "near to far" extrapolation methods must achieve percent level understanding of neutrino and antineutrino interactions; the interaction determines the relationship between experimental observables and the oscillation probability which depends on the neutrino energy. However, recent developments over the last 5 years demonstrate that our understanding of neutrino interactions is insufficient. In particular, the interaction of neutrinos on correlated pairs of nucleons has only recently been added to neutrino interaction simulations. The identification of these processes as interactions on a single nucleon results in a significant bias to the measured mixing parameters, even when near detector i...

An experimental design approach for optimization of spectrophotometric method for estimation of cefixime trihydrate using ninhydrin as derivatizing reagent in bulk and pharmaceutical formulation

Directory of Open Access Journals (Sweden)

Yogita B. Wani

2017-01-01

Full Text Available The aim of the present work is to use experimental design to screen and optimize experimental variables for developing a spectrophotometric method for determining cefixime trihydrate content using ninhydrin as a derivatizing reagent. The method is based on the reaction of the amino group of cefixime with ninhydrin in an alkaline medium to form a yellow-colored derivative (λmax 436 nm. A two-level full factorial design was utilized to screen the effect of ninhydrin reagent concentration (X1, volume of ninhydrin reagent (X2, heating temperature (X3 and heating time (X4 on the formation of the cefixime–ninhydrin complex Y (absorbance. One way ANOVA and Pareto ranking analyses have shown that the ninhydrin reagent concentration (X1, volume of ninhydrin reagent (X2 and heating temperature (X3 were statistically significant factors (P < 0.05 affecting the formation of the cefixime–ninhydrin complex Y (absorbance. A Box-Behnken experimental design with response surface methodology was then utilized to evaluate the main, interaction and quadratic effects of these three factors on the selected response. With the help of a response surface plot and contour plot the optimum values of the selected factors were determined and used for further experiments. These values were a ninhydrin reagent concentration (X1 of 0.2% w/v, volume of ninhydrin reagent (X2 of 1 mL and heating temperature (X3 of 80 °C. The proposed method was validated according to the ICH Q2 (R1 method validation guidelines. The results of the present study have clearly shown that an experimental design concept may be effectively applied to the optimization of a spectrophotometric method for estimating the cefixime trihydrate content in bulk and pharmaceutical formulation with the least number of experimental runs possible.

Comparison of simulated and experimental results of temperature distribution in a closed two-phase thermosyphon cooling system

Science.gov (United States)

Shaanika, E.; Yamaguchi, K.; Miki, M.; Ida, T.; Izumi, M.; Murase, Y.; Oryu, T.; Yanamoto, T.

2017-12-01

Superconducting generators offer numerous advantages over conventional generators of the same rating. They are lighter, smaller and more efficient. Amongst a host of methods for cooling HTS machinery, thermosyphon-based cooling systems have been employed due to their high heat transfer rate and near-isothermal operating characteristics associated with them. To use them optimally, it is essential to study thermal characteristics of these cryogenic thermosyphons. To this end, a stand-alone neon thermosyphon cooling system with a topology resembling an HTS rotating machine was studied. Heat load tests were conducted on the neon thermosyphon cooling system by applying a series of heat loads to the evaporator at different filling ratios. The temperature at selected points of evaporator, adiabatic tube and condenser as well as total heat leak were measured. A further study involving a computer thermal model was conducted to gain further insight into the estimated temperature distribution of thermosyphon components and heat leak of the cooling system. The model employed boundary conditions from data of heat load tests. This work presents a comparison between estimated (by model) and experimental (measured) temperature distribution in a two-phase cryogenic thermosyphon cooling system. The simulation results of temperature distribution and heat leak compared generally well with experimental data.

Faster methods for estimating arc centre position during VAR and results from Ti-6Al-4V and INCONEL 718 alloys

Science.gov (United States)

Nair, B. G.; Winter, N.; Daniel, B.; Ward, R. M.

2016-07-01

Direct measurement of the flow of electric current during VAR is extremely difficult due to the aggressive environment as the arc process itself controls the distribution of current. In previous studies the technique of “magnetic source tomography” was presented; this was shown to be effective but it used a computationally intensive iterative method to analyse the distribution of arc centre position. In this paper we present faster computational methods requiring less numerical optimisation to determine the centre position of a single distributed arc both numerically and experimentally. Numerical validation of the algorithms were done on models and experimental validation on measurements based on titanium and nickel alloys (Ti6Al4V and INCONEL 718). The results are used to comment on the effects of process parameters on arc behaviour during VAR.

Acoustic analysis in Mudejar-Gothic churches: experimental results.

Science.gov (United States)

Galindo, Miguel; Zamarreño, Teófilo; Girón, Sara

2005-05-01

This paper describes the preliminary results of research work in acoustics, conducted in a set of 12 Mudejar-Gothic churches in the city of Seville in the south of Spain. Despite common architectural style, the churches feature individual characteristics and have volumes ranging from 3947 to 10 708 m3. Acoustic parameters were measured in unoccupied churches according to the ISO-3382 standard. An extensive experimental study was carried out using impulse response analysis through a maximum length sequence measurement system in each church. It covered aspects such as reverberation (reverberation times, early decay times), distribution of sound levels (sound strength); early to late sound energy parameters derived from the impulse responses (center time, clarity for speech, clarity, definition, lateral energy fraction), and speech intelligibility (rapid speech transmission index), which all take both spectral and spatial distribution into account. Background noise was also measured to obtain the NR indices. The study describes the acoustic field inside each temple and establishes a discussion for each one of the acoustic descriptors mentioned by using the theoretical models available and the principles of architectural acoustics. Analysis of the quality of the spaces for music and speech is carried out according to the most widespread criteria for auditoria.

Acoustic analysis in Mudejar-Gothic churches: Experimental results

Science.gov (United States)

Galindo, Miguel; Zamarreño, Teófilo; Girón, Sara

2005-05-01

This paper describes the preliminary results of research work in acoustics, conducted in a set of 12 Mudejar-Gothic churches in the city of Seville in the south of Spain. Despite common architectural style, the churches feature individual characteristics and have volumes ranging from 3947 to 10 708 m3. Acoustic parameters were measured in unoccupied churches according to the ISO-3382 standard. An extensive experimental study was carried out using impulse response analysis through a maximum length sequence measurement system in each church. It covered aspects such as reverberation (reverberation times, early decay times), distribution of sound levels (sound strength); early to late sound energy parameters derived from the impulse responses (center time, clarity for speech, clarity, definition, lateral energy fraction), and speech intelligibility (rapid speech transmission index), which all take both spectral and spatial distribution into account. Background noise was also measured to obtain the NR indices. The study describes the acoustic field inside each temple and establishes a discussion for each one of the acoustic descriptors mentioned by using the theoretical models available and the principles of architectural acoustics. Analysis of the quality of the spaces for music and speech is carried out according to the most widespread criteria for auditoria. .

Visual Display of Scientific Studies, Methods, and Results

Science.gov (United States)

Saltus, R. W.; Fedi, M.

2015-12-01

The need for efficient and effective communication of scientific ideas becomes more urgent each year.A growing number of societal and economic issues are tied to matters of science - e.g., climate change, natural resource availability, and public health. Societal and political debate should be grounded in a general understanding of scientific work in relevant fields. It is difficult for many participants in these debates to access science directly because the formal method for scientific documentation and dissemination is the journal paper, generally written for a highly technical and specialized audience. Journal papers are very effective and important for documentation of scientific results and are essential to the requirements of science to produce citable and repeatable results. However, journal papers are not effective at providing a quick and intuitive summary useful for public debate. Just as quantitative data are generally best viewed in graphic form, we propose that scientific studies also can benefit from visual summary and display. We explore the use of existing methods for diagramming logical connections and dependencies, such as Venn diagrams, mind maps, flow charts, etc., for rapidly and intuitively communicating the methods and results of scientific studies. We also discuss a method, specifically tailored to summarizing scientific papers that we introduced last year at AGU. Our method diagrams the relative importance and connections between data, methods/models, results/ideas, and implications/importance using a single-page format with connected elements in these four categories. Within each category (e.g., data) the spatial location of individual elements (e.g., seismic, topographic, gravity) indicates relative novelty (e.g., are these new data?) and importance (e.g., how critical are these data to the results of the paper?). The goal is to find ways to rapidly and intuitively share both the results and the process of science, both for communication

Statistical method for the determination of the ignition energy of dust cloud - experimental validation

Energy Technology Data Exchange (ETDEWEB)

Bernard, S.; Lebecki, K.; Gillard, P.; Youinou, L.; Baudry, G. [University of Orleans, Bourges (France)

2010-05-15

Powdery materials such as metallic or polymer powders play a considerable role in many industrial processes. Their use requires the introduction of preventive safeguard to control the plants safety. The mitigation of an explosion hazard, according to the ATEX 137 Directive (1999/92/EU), requires the assessment of the dust ignition sensitivity. PRISME laboratory (University of Orleans) has developed an experimental set-up and methodology, using the Langlie test, for the quick determination of the explosion sensitivity of dusts. This method requires only 20 shots and ignition sensitivity is evaluated through the E{sub 50} (energy with an ignition probability of 0.5) A Hartmann tube, with a volume of 1.3l, was designed and built. Many results on the energy ignition thresholds of partially oxidised aluminium were obtained using this experimental device and compared to literature. E-50 evolution is the same as MIE but their respective values are different and MIE is lower than E{sub 50} however the link between E{sub 50} and MIE has not been elucidated In this paper, the Langlie method is explained in detail for the determination of the parameters (mean value E{sub 50} and standard deviation {sigma}) of the associated statistic law. The ignition probability versus applied energy is firstly measured for Lycopodium in order to validate the method A comparison between the normal and the lognormal law was achieved and the best fit was obtained with the lognormal law. In a second part, the Langlie test was performed on different dusts such as aluminium, cornstarch, lycopodium, coal, and PA12 in order to determine E-50 and {sigma} for each dust. The energies E{sub 05} and E{sub 10} corresponding respectively to an ignition probability of 0.05 and 0.1 are determined with the lognormal law and compared to MIE find in literature. E{sub 05} and E{sub 10} values of ignition energy were found to be very close and were in good agreement with MIE in the literature.

METHODS OF MEASURING THE EFFECTS OF LIGHTNING BY SIMULATING ITS STRIKES WITH THE INTERVAL ASSESSMENT OF THE RESULTS OF MEASUREMENTS

Directory of Open Access Journals (Sweden)

P. V. Kriksin

2017-01-01

Full Text Available The article presents the results of the development of new methods aimed at more accurate interval estimate of the experimental values of voltages on grounding devices of substations and circuits in the control cables, that occur when lightning strikes to lightning rods; the abovementioned estimate made it possible to increase the accuracy of the results of the study of lightning noise by 28 %. A more accurate value of interval estimation were achieved by developing a measurement model that takes into account, along with the measured values, different measurement errors and includes the special processing of the measurement results. As a result, the interval of finding the true value of the sought voltage is determined with an accuracy of 95 %. The methods can be applied to the IK-1 and IKP-1 measurement complexes, consisting in the aperiodic pulse generator, the generator of high-frequency pulses and selective voltmeters, respectively. To evaluate the effectiveness of the developed methods series of experimental voltage assessments of grounding devices of ten active high-voltage substation have been fulfilled in accordance with the developed methods and traditional techniques. The evaluation results confirmed the possibility of finding the true values of voltage over a wide range, that ought to be considered in the process of technical diagnostics of lightning protection of substations when the analysis of the measurement results and the development of measures to reduce the effects of lightning are being fulfilled. Also, a comparative analysis of the results of measurements made in accordance with the developed methods and traditional techniques has demonstrated that the true value of the sought voltage may exceed the measured value at an average of 28 %, that ought to be considered in the further analysis of the parameters of lightning protection at the facility and in the development of corrective actions. The developed methods have been

Experimental study of sodium droplet burning in free fall. Evaluation of preliminary test results

International Nuclear Information System (INIS)

Miyahara, Shinya; Ara, Kuniaki

1998-08-01

To study a sodium leak and combustion behavior phenomenologically and to construct the mechanistic evaluation method, an experimental series of a sodium droplet burning in free fall is under way. In this study, the accuracy of measurement technique used in the preliminary test was assessed and the modified technique was proposed for the next test series. Analytical study of the test results was also conducted to deduce dominant parameters and important measurement items which would play an important role in the droplet combustion behavior. The results and conclusions are as follows: (1) Assessment of measurement accuracy and modified technique proposed for the next test series. a) Control accuracy of sodium supply system using β-alumina solid electrolyte was sufficient for generation of objective size of single droplet. However, it is necessary to calibrate the correlation between the quantity of electric charge for sodium supply system and that of supplied sodium. b) Measurement accuracy of falling velocity using high-speed video was ±0.33 m/s at an upper part and ±0.48 m/s at a lower part of the measurement. To reduce the error, a high-speed stroboscopic method is recommended to measure the falling velocity of droplet. (2) Results of analytical study and deduced dominant parameters and important measurement items. a) The falling behavior of a burning droplet was described solving the equation of free falling motion for a rigid sphere. In the case of higher falling height, it is necessary to study the burning effects on the falling behavior. b) The mass burned of a falling droplet was calculated using the combustion model according to 'D 2 ' law during the full burning phase. It is necessary to study the dominant chemical reaction in the burning flame because the mass burned depends on the composition of the reaction products. c) The mass burned was calculated using surface oxidation model for preignition phase together with above model. However, it is

Induction methods and formation process of experimental myopia in guinea pigs

Directory of Open Access Journals (Sweden)

Mi-Duo Chen

2016-03-01

Full Text Available Myopia, especially high myopia, is one of the most important eye diseases in the world. For many years the researchers established a variety of animal models and animal experiments to explore the mechanism of development of myopia. Guinea pig is one of the most commonly used myopia models in recent years. It has obvious advantages in many aspects, and it is a kind of experimental animals which is worth to be further applied to different kinds of myopic experiments and to be studied thoroughly. This article reviews the induction methods and the forming process of the guinea pig myopia model.

Recent experimental results in sub- and near-barrier heavy-ion fusion reactions