WorldWideScience

Sample records for models experimental results

  1. Microplasticity of MMC. Experimental results and modelling

    Energy Technology Data Exchange (ETDEWEB)

    Maire, E. (Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, INSA, 69 Villeurbanne (France)); Lormand, G. (Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, INSA, 69 Villeurbanne (France)); Gobin, P.F. (Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, INSA, 69 Villeurbanne (France)); Fougeres, R. (Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, INSA, 69 Villeurbanne (France))

    1993-11-01

    The microplastic behavior of several MMC is investigated by means of tension and compression tests. This behavior is assymetric : the proportional limit is higher in tension than in compression but the work hardening rate is higher in compression. These differences are analysed in terms of maxium of the Tresca's shear stress at the interface (proportional limit) and of the emission of dislocation loops during the cooling (work hardening rate). On another hand, a model is proposed to calculate the value of the yield stress, describing the composite as a material composed of three phases : inclusion, unaffected matrix and matrix surrounding the inclusion having a gradient in the density of the thermally induced dilocations. (orig.).

  2. Waste glass corrosion modeling: Comparison with experimental results

    International Nuclear Information System (INIS)

    Bourcier, W.L.

    1994-01-01

    Models for borosilicate glass dissolution must account for the processes of (1) kinetically-controlled network dissolution, (2) precipitation of secondary phases, (3) ion exchange, (4) rate-limiting diffusive transport of silica through a hydrous surface reaction layer, and (5) specific glass surface interactions with dissolved cations and anions. Current long-term corrosion models for borosilicate glass employ a rate equation consistent with transition state theory embodied in a geochemical reaction-path modeling program that calculates aqueous phase speciation and mineral precipitation/dissolution. These models are currently under development. Future experimental and modeling work to better quantify the rate-controlling processes and validate these models are necessary before the models can be used in repository performance assessment calculations

  3. Verification of aseismic design model by using experimental results

    International Nuclear Information System (INIS)

    Mizuno, N.; Sugiyama, N.; Suzuki, T.; Shibata, Y.; Miura, K.; Miyagawa, N.

    1985-01-01

    A lattice model is applied as an analysis model for an aseismic design of the Hamaoka nuclear reactor building. With object to verify an availability of this design model, two reinforced concrete blocks are constructed on the ground and the forced vibration tests are carried out. The test results are well followed by simulation analysis using the lattice model. Damping value of the ground obtained from the test is more conservative than the design value. (orig.)

  4. Impact Flash Physics: Modeling and Comparisons With Experimental Results

    Science.gov (United States)

    Rainey, E.; Stickle, A. M.; Ernst, C. M.; Schultz, P. H.; Mehta, N. L.; Brown, R. C.; Swaminathan, P. K.; Michaelis, C. H.; Erlandson, R. E.

    2015-12-01

    horizontal. High-speed radiometer measurements were made of the time-dependent impact flash at wavelengths of 350-1100 nm. We will present comparisons between these measurements and the output of APL's model. The results of this validation allow us to determine basic relationships between observed optical signatures and impact conditions.

  5. Modeling of rock friction 1. Experimental results and constitutive equations

    International Nuclear Information System (INIS)

    Dieterich, J.H.

    1979-01-01

    Direct shear experiments on ground surfaces of a granodiorite from Raymond, California, at normal stresses of approx.6 MPa demonstrate that competing time, displacement, and velocity, effects control rock friction. It is proposed that the strength of the population of points of contacts between sliding surfaces determines frictional strength and that the population of contacts changes continuously with displacements. Previous experiments demonstrate that the strength of the contacts increases with the age of the contacts. The present experiments establish that a characteristic displacement, proportional to surface roughness, is required to change the population of contacts. Hence during slip the average age of the points of contact and therefore frictional strength decrease as slip velocity increases. Displacement weakening and consequently the potential for unstable slip occur whenever displacement reduces the average age of the contacts. In addition to this velocity dependency, which arises from displacement dependency and time dependency, the experiments also show a competing but transient increase in friction whenever slip velocity increases. Creep of the sliding surface at stresses below that for steady state slip also observed. Constitutive relationships are developed that permit quantitative simulation of the friction versus displacement data as a function of surface roughness and for different time and velocity histories. Unstable slip in experiments is controlled by these constitutive effects and by the stiffness of the experimental system. It is argued that analogous properties control earthquake instability

  6. An outcome-based learning model to identify emerging threats : experimental and simulation results.

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Moyano, I. J.; Conrad, S. H.; Andersen, D. F.; Decision and Information Sciences; SNL; Univ. at Albany

    2007-01-01

    The authors present experimental and simulation results of an outcome-based learning model as it applies to the identification of emerging threats. This model integrates judgment, decision making, and learning theories to provide an integrated framework for the behavioral study of emerging threats.

  7. Updating Finite Element Model of a Wind Turbine Blade Section Using Experimental Modal Analysis Results

    Directory of Open Access Journals (Sweden)

    Marcin Luczak

    2014-01-01

    Full Text Available This paper presents selected results and aspects of the multidisciplinary and interdisciplinary research oriented for the experimental and numerical study of the structural dynamics of a bend-twist coupled full scale section of a wind turbine blade structure. The main goal of the conducted research is to validate finite element model of the modified wind turbine blade section mounted in the flexible support structure accordingly to the experimental results. Bend-twist coupling was implemented by adding angled unidirectional layers on the suction and pressure side of the blade. Dynamic test and simulations were performed on a section of a full scale wind turbine blade provided by Vestas Wind Systems A/S. The numerical results are compared to the experimental measurements and the discrepancies are assessed by natural frequency difference and modal assurance criterion. Based on sensitivity analysis, set of model parameters was selected for the model updating process. Design of experiment and response surface method was implemented to find values of model parameters yielding results closest to the experimental. The updated finite element model is producing results more consistent with the measurement outcomes.

  8. 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

  9. Phase Partitioning of Common Alcohols With BTEX Compounds in Water: Comparison Between Modeling and Experimental Results

    Science.gov (United States)

    Lee, K. Y.

    2007-12-01

    This study compares the modeling and experimental results on the equilibrium phase partitioning behavior of three common alcohols (ethanol, isopropanol, and methanol) in a two-phase system consisting of water and a BTEX compound. A previously developed computer program is used to generate ternary phase diagrams for each alcohol-water-NAPL mixture combination, where the required activity coefficients are estimated using the UNIFAC model. A set of laboratory experiments is conducted to determine the maximum single-phase water content for every alcohol-water-NAPL mixture combination considered in this study, where the initial volume composition is 85 percent alcohol and 15 percent NAPL. Comparison of experimental results against UNIFAC- derived modeling results shows good agreement for mixtures containing ethanol and methanol, but relatively poor agreement for mixtures containing isopropanol.

  10. Study on driver model for hybrid truck based on driving simulator experimental results

    Directory of Open Access Journals (Sweden)

    Dam Hoang Phuc

    2018-04-01

    Full Text Available In this paper, a proposed car-following driver model taking into account some features of both the compensatory and anticipatory model representing the human pedal operation has been verified by driving simulator experiments with several real drivers. The comparison between computer simulations performed by determined model parameters with the experimental results confirm the correctness of this mathematical driver model and identified model parameters. Then the driver model is joined to a hybrid vehicle dynamics model and the moderate car following maneuver simulations with various driver parameters are conducted to investigate influences of driver parameters on vehicle dynamics response and fuel economy. Finally, major driver parameters involved in the longitudinal control of drivers are clarified. Keywords: Driver model, Driver-vehicle closed-loop system, Car Following, Driving simulator/hybrid electric vehicle (B1

  11. 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

  12. Computations for the 1:5 model of the THTR pressure vessel compared with experimental results

    International Nuclear Information System (INIS)

    Stangenberg, F.

    1972-01-01

    In this report experimental results measured at the 1:5-model of the prestressed concrete pressure vessel of the THTR-nuclear power station Schmehausen in 1971, are compared with the results of axis-symmetrical computations. Linear-elastic computations were performed as well as approximate computations for overload pressures taking into consideration the influences of the load history (prestressing, temperature, creep) and the effects of the steel components. (orig.) [de

  13. 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.

  14. Verification of simulation model with COBRA-IIIP code by confrontment of experimental results

    International Nuclear Information System (INIS)

    Silva Galetti, M.R. da; Pontedeiro, A.C.; Oliveira Barroso, A.C. de

    1985-01-01

    It is presented an evaluation of the COBRA IIIP/MIT code (of thermal hydraulic analysis by subchannels), comparing their results with experimental data obtained in stationary and transient regimes. It was done a study to calculate the spatial and temporal critical heat flux. It is presented a sensitivity study of simulation model related to the turbulent mixture and the number of axial intervals. (M.C.K.) [pt

  15. Isothermal (vapour + liquid) equilibrium of (cyclic ethers + chlorohexane) mixtures: Experimental results and SAFT modelling

    International Nuclear Information System (INIS)

    Bandres, I.; Giner, B.; Lopez, M.C.; Artigas, H.; Lafuente, C.

    2008-01-01

    Experimental data for the isothermal (vapour + liquid) equilibrium of mixtures formed by several cyclic ethers (tetrahydrofuran, tetrahydropyran, 1,3-dioxolane, and 1,4-dioxane) and chlorohexane at temperatures of (298.15 and 328.15) K are presented. Experimental results have been discussed in terms of both, molecular characteristics of pure compounds and potential intermolecular interaction between them using thermodynamic information of the mixtures obtained earlier. Furthermore, the influence of the temperature on the (vapour + liquid) equilibrium of these mixtures has been explored and discussed. Transferable parameters of the SAFT-VR approach together with standard combining rules have been used to model the phase equilibrium of the mixtures and a description of the (vapour + liquid) equilibrium of them that is in excellent agreement with the experimental data are provided

  16. Comparison of Experimental Surface and Flow Field Measurements to Computational Results of the Juncture Flow Model

    Science.gov (United States)

    Roozeboom, Nettie H.; Lee, Henry C.; Simurda, Laura J.; Zilliac, Gregory G.; Pulliam, Thomas H.

    2016-01-01

    Wing-body juncture flow fields on commercial aircraft configurations are challenging to compute accurately. The NASA Advanced Air Vehicle Program's juncture flow committee is designing an experiment to provide data to improve Computational Fluid Dynamics (CFD) modeling in the juncture flow region. Preliminary design of the model was done using CFD, yet CFD tends to over-predict the separation in the juncture flow region. Risk reduction wind tunnel tests were requisitioned by the committee to obtain a better understanding of the flow characteristics of the designed models. NASA Ames Research Center's Fluid Mechanics Lab performed one of the risk reduction tests. The results of one case, accompanied by CFD simulations, are presented in this paper. Experimental results suggest the wall mounted wind tunnel model produces a thicker boundary layer on the fuselage than the CFD predictions, resulting in a larger wing horseshoe vortex suppressing the side of body separation in the juncture flow region. Compared to experimental results, CFD predicts a thinner boundary layer on the fuselage generates a weaker wing horseshoe vortex resulting in a larger side of body separation.

  17. Soil gas and radon entry into a simple test structure: Comparison of experimental and modelling results

    DEFF Research Database (Denmark)

    Andersen, C.E.; Søgaard-Hansen, J.; Majborn, B.

    1994-01-01

    A radon test structure has been established at a field site at Riso National Laboratory. Measurements have been made of soil gas entry rates, pressure couplings and radon depletion. The experimental results have been compared with results obtained from measured soil parameters and a two......-dimensional steady-state numerical model of Darcy flow and combined diffusive and advective transport of radon. For most probe locations, the calculated values of the pressure couplings and the radon depletion agree well with the measured values, thus verifying important elements of the Darcy flow approximation......, and the ability of the model to treat combined diffusive and advective transport of radon. However, the model gives an underestimation of the soil gas entry rate. Even if it is assumed that the soil has a permeability equal to the highest of the measured values, the model underestimates the soil gas entry rate...

  18. Comparison of experimental data with results of some drying models for regularly shaped products

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, Ahmet [Aksaray University, Department of Mechanical Engineering, Aksaray (Turkey); Aydin, Orhan [Karadeniz Technical University, Department of Mechanical Engineering, Trabzon (Turkey); Dincer, Ibrahim [University of Ontario Institute of Technology, Faculty of Engineering and Applied Science, Oshawa, ON (Canada)

    2010-05-15

    This paper presents an experimental and theoretical investigation of drying of moist slab, cylinder and spherical products to study dimensionless moisture content distributions and their comparisons. Experimental study includes the measurement of the moisture content distributions of slab and cylindrical carrot, slab and cylindrical pumpkin and spherical blueberry during drying at various temperatures (e.g., 30, 40, 50 and 60 C) at specific constant velocity (U = 1 m/s) and the relative humidity {phi}=30%. In theoretical analysis, two moisture transfer models are used to determine drying process parameters (e.g., drying coefficient and lag factor) and moisture transfer parameters (e.g., moisture diffusivity and moisture transfer coefficient), and to calculate the dimensionless moisture content distributions. The calculated results are then compared with the experimental moisture data. A considerably high agreement is obtained between the calculations and experimental measurements for the cases considered. The effective diffusivity values were evaluated between 0.741 x 10{sup -5} and 5.981 x 10{sup -5} m{sup 2}/h for slab products, 0.818 x 10{sup -5} and 6.287 x 10{sup -5} m{sup 2}/h for cylindrical products and 1.213 x 10{sup -7} and 7.589 x 10{sup -7} m{sup 2}/h spherical products using the model-I and 0.316 x 10{sup -5}-5.072 x 10{sup -5} m{sup 2}/h for slab products, 0.580 x 10{sup -5}-9.587 x 10{sup -5} m{sup 2}/h for cylindrical products and 1.408 x 10{sup -7}-13.913 x 10{sup -7} m{sup 2}/h spherical products using the model-II. (orig.)

  19. RC Beams Strengthened with Mechanically Fastened Composites: Experimental Results and Numerical Modeling

    Directory of Open Access Journals (Sweden)

    Enzo Martinelli

    2014-03-01

    Full Text Available The use of mechanically-fastened fiber-reinforced polymer (MF-FRP systems has recently emerged as a competitive solution for the flexural strengthening of reinforced concrete (RC beams and slabs. An overview of the experimental research has proven the effectiveness and the potentiality of the MF-FRP technique which is particularly suitable for emergency repairs or when the speed of installation and immediacy of use are imperative. A finite-element (FE model has been recently developed by the authors with the aim to simulate the behavior of RC beams strengthened in bending by MF-FRP laminates; such a model has also been validated by using a wide experimental database collected from the literature. By following the previous study, the FE model and the assembled database are considered herein with the aim of better exploring the influence of some specific aspects on the structural response of MF-FRP strengthened members, such as the bearing stress-slip relationship assumed for the FRP-concrete interface, the stress-strain law considered for reinforcing steel rebars and the cracking process in RC members resulting in the well-known tension stiffening effect. The considerations drawn from this study will be useful to researchers for the calibration of criteria and design rules for strengthening RC beams through MF-FRP laminates.

  20. Model predictions and experimental results on self-heating prevention of stockpiled coals

    Energy Technology Data Exchange (ETDEWEB)

    Fierro, V.; Miranda, J.L.; Romero, C.; Andres, J.M.; Arriaga, A.; Schmal, D. [Instituto de Carboquimica, Zaragoza (Spain)

    2001-01-01

    The spontaneous combustion of coal stockpiles is a serious economic and safety problem. This phenomenon is analysed using a TNO-model modified to predict the spontaneous heating behaviour of coal piles built with 'Mezcla', a mixture of low rank coals from Teruel (Spain). The simulation carried out with the mathematical model for this coal showed that the pile porosity or voidage and wind speed play an important role, although voidage is decisive and controls the effect of the wind velocity. To reduce the negative effects of both factors, five test coal piles (2000-3000 t) were built and several measures were applied to four of them: periodic compaction, use of a low angle slope, protection of the stockpiled coal with an artificial wind barrier and covering it with an ash-water slurry. The heat losses were experimentally determined and it was found that the mathematical model gave predictions of the right order of magnitude of time, site of spontaneous combustion and magnitude of calorific losses. All the methods of protection applied to decrease the self-heating of coal were effective, but the experimental results indicate that the most economical way to avoid the heat losses is the use of an ash-water slurry to cover the coal pile. 28 refs., 8 figs., 5 tabs.

  1. Comparison of Computational and Experimental Microphone Array Results for an 18%-Scale Aircraft Model

    Science.gov (United States)

    Lockard, David P.; Humphreys, William M.; Khorrami, Mehdi R.; Fares, Ehab; Casalino, Damiano; Ravetta, Patricio A.

    2015-01-01

    An 18%-scale, semi-span model is used as a platform for examining the efficacy of microphone array processing using synthetic data from numerical simulations. Two hybrid RANS/LES codes coupled with Ffowcs Williams-Hawkings solvers are used to calculate 97 microphone signals at the locations of an array employed in the NASA LaRC 14x22 tunnel. Conventional, DAMAS, and CLEAN-SC array processing is applied in an identical fashion to the experimental and computational results for three different configurations involving deploying and retracting the main landing gear and a part span flap. Despite the short time records of the numerical signals, the beamform maps are able to isolate the noise sources, and the appearance of the DAMAS synthetic array maps is generally better than those from the experimental data. The experimental CLEAN-SC maps are similar in quality to those from the simulations indicating that CLEAN-SC may have less sensitivity to background noise. The spectrum obtained from DAMAS processing of synthetic array data is nearly identical to the spectrum of the center microphone of the array, indicating that for this problem array processing of synthetic data does not improve spectral comparisons with experiment. However, the beamform maps do provide an additional means of comparison that can reveal differences that cannot be ascertained from spectra alone.

  2. Investigation of sonar transponders for offshore wind farms: modeling approach, experimental setup, and results.

    Science.gov (United States)

    Fricke, Moritz B; Rolfes, Raimund

    2013-11-01

    The installation of offshore wind farms in the German Exclusive Economic Zone requires the deployment of sonar transponders to prevent collisions with submarines. The general requirements for these systems have been previously worked out by the Research Department for Underwater Acoustics and Marine Geophysics of the Bundeswehr. In this article, the major results of the research project "Investigation of Sonar Transponders for Offshore Wind Farms" are presented. For theoretical investigations a hybrid approach was implemented using the boundary element method to calculate the source directivity and a three-dimensional ray-tracing algorithm to estimate the transmission loss. The angle-dependence of the sound field as well as the weather-dependence of the transmission loss are compared to experimental results gathered at the offshore wind farm alpha ventus, located 45 km north of the island Borkum. While theoretical and experimental results are in general agreement, the implemented model slightly underestimates scattering at the rough sea surface. It is found that the source level of 200 dB re 1 μPa at 1 m is adequate to satisfy the detectability of the warning sequence at distances up to 2 NM (≈3.7 km) within a horizontal sector of ±60° if realistic assumptions about signal-processing and noise are made. An arrangement to enlarge the angular coverage is discussed.

  3. Dynamics of dual prism adaptation: relating novel experimental results to a minimalistic neural model.

    Directory of Open Access Journals (Sweden)

    Orlando Arévalo

    Full Text Available In everyday life, humans interact with a dynamic environment often requiring rapid adaptation of visual perception and motor control. In particular, new visuo-motor mappings must be learned while old skills have to be kept, such that after adaptation, subjects may be able to quickly change between two different modes of generating movements ('dual-adaptation'. A fundamental question is how the adaptation schedule determines the acquisition speed of new skills. Given a fixed number of movements in two different environments, will dual-adaptation be faster if switches ('phase changes' between the environments occur more frequently? We investigated the dynamics of dual-adaptation under different training schedules in a virtual pointing experiment. Surprisingly, we found that acquisition speed of dual visuo-motor mappings in a pointing task is largely independent of the number of phase changes. Next, we studied the neuronal mechanisms underlying this result and other key phenomena of dual-adaptation by relating model simulations to experimental data. We propose a simple and yet biologically plausible neural model consisting of a spatial mapping from an input layer to a pointing angle which is subjected to a global gain modulation. Adaptation is performed by reinforcement learning on the model parameters. Despite its simplicity, the model provides a unifying account for a broad range of experimental data: It quantitatively reproduced the learning rates in dual-adaptation experiments for both direct effect, i.e. adaptation to prisms, and aftereffect, i.e. behavior after removal of prisms, and their independence on the number of phase changes. Several other phenomena, e.g. initial pointing errors that are far smaller than the induced optical shift, were also captured. Moreover, the underlying mechanisms, a local adaptation of a spatial mapping and a global adaptation of a gain factor, explained asymmetric spatial transfer and generalization of prism

  4. Experimental checking results of mathematical modeling of the radiation environment sensor based on diamond detectors

    International Nuclear Information System (INIS)

    Gladchenkov, E V; Kolyubin, V A; Nedosekin, P G; Zaharchenko, K V; Ibragimov, R F; Kadilin, V V; Tyurin, E M

    2017-01-01

    Were conducted a series of experiments, the purpose of which had to verify the mathematical model of the radiation environment sensor. Theoretical values of the beta particles count rate from 90 Sr - 90 Y source registered by radiation environment sensor was compared with the experimental one. Theoretical (calculated) count rate of beta particles was found with using the developed mathematical model of the radiation environment sensor. Deviation of the calculated values of the beta particle count rate does not exceed 10% from the experimental. (paper)

  5. 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

    regenerator (AMR). In particular, the effect of geometric demagnetization in the regenerator is included in a simplified manner. The model and experimental data are in good agreement while the effect of demagnetization is seen to degrade the performance. It is concluded from the experiments that both thinner...

  6. Montmorillonite stability - experimental results

    International Nuclear Information System (INIS)

    Karnland, Ola; Birgersson, Martin; Olsson, Siv

    2012-01-01

    Document available in extended abstract form only. Several repository concepts for spent nuclear fuel comprise a bentonite buffer which encloses the fuel containers. The function of this bentonite buffer is critically dependent on the properties of the swelling mineral in the bentonite, which typically is montmorillonite in commercial high quality bentonites. The physical and chemical properties of the montmorillonite in bentonites have consequently been studied in various types of analyses in several countries, and the results have been the basis for the design of the bentonite buffer with respect to size, degree of compaction etc (SKB TR-10-47). Significant changes in the montmorillonite structure with time may change the properties of the bentonite buffer and jeopardize the isolating function. In nature, illite is the most common alteration product from montmorillonite, and a 50% alteration reduces, for instance, the swelling pressure by one order of magnitude. Fortunately, the process is very slow at typical repository temperatures, and also in the perspective of repository life-time no significant alteration is expected according to the available kinetic models. The models are, however, based on laboratory batch experiments performed at temperatures, which by necessity are much higher than what is planned for in a repository. Alternatively, the models are based on natural montmorillonite-to-illite alteration in e.g. deep sediments. In both cases there are divergences from repository conditions which limit the arguments for the bentonite buffer stability. The mechanism by which the montmorillonite-to-illite reaction takes place is not fully understood, but the overall process may be represented by the following schematic reaction: Na + montmorillonite + K + + Al 3+ → illite + SiO 2 + Na + . Aluminum may be supplied from the bentonite itself, but potassium has to be transported to the buffer from an external source in order to give a significant alteration in

  7. 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

  8. Modeled and experimental results of an omnidirectional free-space optical receiver architecture

    Science.gov (United States)

    Murshid, Syed H.; Lovell, Gregory L.; Finch, Michael F.

    2017-03-01

    Free-space optical (FSO) communications provide point-to-point connectivity while offering many advantages in size, weight, and power as compared to radio frequency. It has the potential to provide fiber-optic data rates without the need for lengthy fiber cables. Omnidirectional FSO, also known as O-FSO systems, provide a non-line-of-sight option for data communications. They are gaining popularity in short-distance networks. Most existing O-FSO links range from 1 to 100 m and present experimental/simulated data rates ranging between 5 kb/s and 1 Mb/s. A 2.5-Gb/s O-FSO system was recently reported with a range of 25 cm. This paper employs a fiber bundle as an O-FSO receiver. The energy collected by the receiver is related to the acceptance cone of each fiber. The fiber bundle integrates the optical power gathered by the individual fibers and couples it to the photodetector. Experimental data rates approaching 100 kb/s over a meter long system are presented, whereas simulated results support a data rate up to 52 Mb/s for distances approaching a kilometer. Theoretical and experimental optical power versus range is also presented for the proposed O-FSO architecture, using on-off keying.

  9. Combustion synthesis of TiB2-based cermets: modeling and experimental results

    International Nuclear Information System (INIS)

    Martinez Pacheco, M.; Bouma, R.H.B.; Katgerman, L.

    2008-01-01

    TiB 2 -based cermets are prepared by combustion synthesis followed by a pressing stage in a granulate medium. Products obtained by combustion synthesis are characterized by a large remaining porosity (typically 50%). To produce dense cermets, a subsequent densification step is performed after the combustion process and when the reacted material is still hot. To design the process, numerical simulations are carried out and compared to experimental results. In addition, physical and electrical properties of the products related to electrical contact applications are evaluated. (orig.)

  10. Wind Turbine Performance in Controlled Conditions: BEM Modeling and Comparison with Experimental Results

    Directory of Open Access Journals (Sweden)

    David A. Johnson

    2016-01-01

    Full Text Available Predictions of the performance of operating wind turbines are challenging for many reasons including the unsteadiness of the wind and uncertainties in blade aerodynamic behaviour. In the current study an extended blade element momentum (BEM program was developed to compute the rotor power of an existing 4.3 m diameter turbine and compare predictions with reported controlled experimental measurements. Beginning with basic blade geometry and the iterative computation of aerodynamic properties, the method integrated the BEM analysis into the program workflow ensuring that the power production by a blade element agreed with its lift and drag data at the same Reynolds number. The parametric study using the extended BEM algorithm revealed the close association of the power curve behaviour with the aerodynamic characteristics of the blade elements, the discretization of the aerodynamic span, and the dependence on Reynolds number when the blades were stalled. Transition prediction also affected overall performance, albeit to a lesser degree. Finally, to capture blade finite area effects, the tip loss model was adjusted depending on stall conditions. The experimental power curve for the HAWT of the current study was closely matched by the extended BEM simulation.

  11. Comparison of analytical models and experimental results for single-event upset in CMOS SRAMs

    International Nuclear Information System (INIS)

    Mnich, T.M.; Diehl, S.E.; Shafer, B.D.

    1983-01-01

    In an effort to design fully radiation-hardened memories for satellite and deep-space applications, a 16K and a 2K CMOS static RAM were modeled for single-particle upset during the design stage. The modeling resulted in the addition of a hardening feedback resistor in the 16K remained tentatively unaltered. Subsequent experiments, using the Lawrence Berkeley Laboratories' 88-inch cyclotron to accelerate krypton and oxygen ions, established an upset threshold for the 2K and the 16K without resistance added, as well as a hardening threshold for the 16K with feedback resistance added. Results for the 16K showed it to be hardenable to the higher level than previously published data for other unhardened 16K RAMs. The data agreed fairly well with the modeling results; however, a close look suggests that modification of the simulation methodology is required to accurately predict the resistance necessary to harden the RAM cell

  12. alpha-pinene oxidation by OH : Box model simulation of experimental results

    Science.gov (United States)

    Capouet, M.; Fantechi, G.; Peeters, J.; Noziere, B.; Muller, J.-F.

    2003-04-01

    A detailed gas-phase mechanism for the oxidation of alpha-pinene and pinonaldehyde by OH in the presence of NOx (Peeters et al., 2001; Fantechi et al., 2002) has been implemented in a box model. A module describing the gas/particle partitioning of the semi-volatile products has been developed and coupled to the gas-phase model. The estimation of the gas/particle partitioning coefficients requires the prediction of the saturation vapour pressures for the compounds produced in the mechanism. The method developed in this work is outlined and compared with two published methods : The Marrero and Gani (2001) and the UNIFAC ( Asher et al, 2002) methods. In order to validate the gas-phase mechanism and the partitioning model, we present comparisons of simulations results with time-dependent product concentrations measured in a series of laboratories experiments performed by Noziere et al. (1999). In these experiments, gaseous products as well as total secondary organic aerosol were measured in a variety of conditions (initial alpha-pinene, NOx, type of lamp and radical precursor). The results of these comparisons are discussed. An excellent agreement is generally observed for most gaseous products, in contrast with a very poor match between modelled and observed aerosol concentrations, pointing to the existence of missing heterogeneous processes.

  13. U.S. Department of Energy Reference Model Program RM1: Experimental Results.

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Craig [Univ. of Minnesota, Minneapolis, MN (United States); Neary, Vincent Sinclair [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gunawan, Budi [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Guala, Michele [Univ. of Minnesota, Minneapolis, MN (United States); Sotiropoulos, Fotis [Univ. of Minnesota, Minneapolis, MN (United States)

    2017-08-01

    The Reference Model Project (RMP), sponsored by the U.S. Department of Energy’s (DOE) Wind and Water Power Technologies Program within the Office of Energy Efficiency & Renewable Energy (EERE), aims at expediting industry growth and efficiency by providing nonproprietary Reference Models (RM) of MHK technology designs as study objects for opensource research and development (Neary et al. 2014a,b). As part of this program, MHK turbine models were tested in a large open channel facility at the University of Minnesota’s St. Anthony Falls Laboratory (UMN-SAFL). Reference Model 1 (RM1) is a 1:40 geometric scale dual-rotor axial flow horizontal axis device with counter-rotating rotors, each with a rotor diameter dT = 0.5m. Precise blade angular position and torque measurements were synchronized with three acoustic Doppler velocimeters (ADVs) aligned with each rotor and the midpoint for RM1. Flow conditions for each case were controlled such that depth, h = 1m, and volumetric flow rate, Qw = 2.425m3s-1, resulting in a hub height velocity of approximately Uhub = 1.05ms-1 and blade chord length Reynolds numbers of Rec ≈ 3.0x105. Vertical velocity profiles collected in the wake of each device from 1 to 10 rotor diameters are used to estimate the velocity recovery and turbulent characteristics in the wake, as well as the interaction of the counter-rotating rotor wakes. The development of this high resolution laboratory investigation provides a robust dataset that enables assessing turbulence performance models and their ability to accurately predict device performance metrics, including computational fluid dynamics (CFD) models that can be used to predict turbulent inflow environments, reproduce wake velocity deficit, recovery and higher order turbulent statistics, as well as device performance metrics.

  14. U.S. Department of Energy Reference Model Program RM1: Experimental Results

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Craig [Univ. of Minnesota, Minneapolis, MN (United States); Neary, Vincent Sinclair [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gunawan, Budi [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Guala, Michele [Univ. of Minnesota, Minneapolis, MN (United States); Sotiropoulos, Fotis [Univ. of Minnesota, Minneapolis, MN (United States)

    2014-10-01

    The Reference Model Project (RMP), sponsored by the U.S. Department of Energy’s (DOE) Wind and Water Power Technologies Program within the Office of Energy Efficiency & Renewable Energy (EERE), aims at expediting industry growth and efficiency by providing non-proprietary Reference Models (RM) of MHK technology designs as study objects for open-source research and development (Neary et al. 2014a,b). As part of this program, MHK turbine models were tested in a large open channel facility at the University of Minnesota’s St. Anthony Falls Laboratory (UMN-SAFL). Reference Model 1 (RM2) is a 1:40 geometric scale dual-rotor axial flow horizontal axis device with counter-rotating rotors, each with a rotor diameter dT = 0.5m. Precise blade angular position and torque measurements were synchronized with three acoustic Doppler velocimeters (ADVs) aligned with each rotor and the midpoint for RM1. Flow conditions for each case were controlled such that depth, h = 1m, and volumetric flow rate, Qw = 2.425m3s-1, resulting in a hub height velocity of approximately Uhub = 1.05ms-1 and blade chord length Reynolds numbers of Rec ≈ 3.0x105. Vertical velocity profiles collected in the wake of each device from 1 to 10 rotor diameters are used to estimate the velocity recovery and turbulent characteristics in the wake, as well as the interaction of the counter-rotating rotor wakes. The development of this high resolution laboratory investigation provides a robust dataset that enables assessing turbulence performance models and their ability to accurately predict device performance metrics, including computational fluid dynamics (CFD) models that can be used to predict turbulent inflow environments, reproduce wake velocity deficit, recovery and higher order turbulent statistics, as well as device performance metrics.

  15. RETRACTED — Simple and efficient ANN model proposed for the temperature dependence of EDFA gain based on experimental results

    Science.gov (United States)

    Yucel, Murat; Celebi, Fatih V.; Haldun Goktas, H.

    2013-02-01

    This study deals with the Artificial Neural Network (ANN) model of erbium-doped fiber amplifier (EDFA) gain in C band based on our experimental results at the temperature range of 0-60 °C. An ANN with three inputs and one output is considered where the inputs are signal power, wavelength, temperature and the output is EDFA gain. The network parameters are optimized by monitoring mean square error (MSE) at the output. The proposed dynamic model tremendously reduces the computational in the order of milliseconds which computes the EDFA gain at different operating conditions and is in very good agreement with our experimental findings.

  16. Sound propagation in forests: A comparison of experimental results and values predicted by the Nord 2000 model

    DEFF Research Database (Denmark)

    Tarrero, A.I.; Martín, M.A.; González, J.

    2008-01-01

    The purpose of the work described in this paper is twofold: (i) to present the results of an experimental investigation of the sound attenuation in different types of forest, and (ii) to validate a part of the Nord 2000 model. A number of measurements have been carried out in regular and irregular...

  17. Optimal piezoelectric beam shape for single and broadband vibration energy harvesting: Modeling, simulation and experimental results

    Science.gov (United States)

    Muthalif, Asan G. A.; Nordin, N. H. Diyana

    2015-03-01

    Harvesting energy from the surroundings has become a new trend in saving our environment. Among the established ones are solar panels, wind turbines and hydroelectric generators which have successfully grown in meeting the world's energy demand. However, for low powered electronic devices; especially when being placed in a remote area, micro scale energy harvesting is preferable. One of the popular methods is via vibration energy scavenging which converts mechanical energy (from vibration) to electrical energy by the effect of coupling between mechanical variables and electric or magnetic fields. As the voltage generated greatly depends on the geometry and size of the piezoelectric material, there is a need to define an optimum shape and configuration of the piezoelectric energy scavenger. In this research, mathematical derivations for unimorph piezoelectric energy harvester are presented. Simulation is done using MATLAB and COMSOL Multiphysics software to study the effect of varying the length and shape of the beam to the generated voltage. Experimental results comparing triangular and rectangular shaped piezoelectric beam are also presented.

  18. U.S. Department of Energy Reference Model Program RM2: Experimental Results

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Craig [Univ. of Minnesota, Minneapolis, MN (United States). St. Anthony Falls Laboratory (UMN-SAFL); Neary, Vincent Sinclair [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Gunawan, Budi [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Guala, Michele [Univ. of Minnesota, Minneapolis, MN (United States). St. Anthony Falls Laboratory (UMN-SAFL); Sotiropoulos, Fotis [Univ. of Minnesota, Minneapolis, MN (United States). St. Anthony Falls Laboratory (UMN-SAFL)

    2014-08-01

    The Reference Model Project (RMP), sponsored by the U.S. Department of Energy’s (DOE) Wind and Water Power Technologies Program within the Office of Energy Efficiency & Renewable Energy (EERE), aims at expediting industry growth and efficiency by providing non-proprietary Reference Models (RM) of MHK technology designs as study objects for open-source research and development (Neary et al. 2014a,b). As part of this program, MHK turbine models were tested in a large open channel facility at the University of Minnesota’s St. Anthony Falls Laboratory (UMN - SAFL) . Reference Model 2 (RM2) is a 1:15 geometric scale dual - rotor cross flow vertical axis device with counter - rotating rotors, each with a rotor diameter dT = 0.43m and rotor height, hT = 0.323 m. RM2 is a river turbine designed for a site modeled after a reach in the lower Mississippi River near Baton Rouge, Louisiana (Barone et al. 2014) . Precise blade angular position and torque measurements were synchronized with three acoustic Doppler velocimeters (ADV) aligned with each rotor and the midpoint for RM2 . Flow conditions for each case were controlled such that depth, h = 1m, and volumetric flow rate, Qw = 2. 35m3s-1 , resulting in a hub height velocity of approximately Uhub = 1. 2 ms-1 and blade chord length Reynolds numbers of Rec = 6 .1x104. Vertical velocity profiles collected in the wake of each device from 1 to 10 rotor diameters are used to estimate the velocity recovery and turbulent characteristics in the wake, as well as the interaction of the counter-rotating rotor wakes. The development of this high resolution laboratory investigation provides a robust dataset that enables assessing computational fluid dynamics (CFD) models and their ability to accurately simulate turbulent inflow environments, device performance metrics, and to reproduce wake velocity deficit, recovery and higher order

  19. A Neighborhood-Scale Green Infrastructure Retrofit: Experimental Results, Model Simulations, and Resident Perspectives

    Science.gov (United States)

    Jefferson, A.; Avellaneda, P. M.; Jarden, K. M.; Turner, V. K.; Grieser, J.

    2016-12-01

    Distributed green infrastructure approaches to stormwater management that can be retrofit into existing development are of growing interest, but questions remain about their effectiveness at the watershed-scale. In suburban northeastern Ohio, homeowners on a residential street with 55% impervious surface were given the opportunity for free rain barrels, rain gardens, and bioretention cells. Of 163 parcels, only 22 owners (13.5%) chose to participate, despite intense outreach efforts. After pre-treatment monitoring, 37 rain barrels, 7 rain gardens, and 16 street-side bioretention cells were installed in 2013-2014. Using a paired watershed approach, a reduction in up to 33% of peak flow and 40% of total runoff volume per storm was measured in the storm sewer. Using the monitoring data, a calibrated and validated SWMM model was built to explore the long-term effectiveness of the green infrastructure against a wider range of hydrological conditions. Model results confirm the effectiveness of green infrastructure in reducing surface runoff and increasing infiltration and evaporation. Based on 20 years of historical precipitation data, the model shows that the green infrastructure is capable of reducing flows by >40% at the 1, 2, and 5 year return period, suggesting some resilience to projected increases in precipitation intensity in a changing climate. Further, in this project, more benefit is derived from the street-side bioretention cells than from the rain barrels and gardens that treat rooftop runoff. Substantial hydrological gains were achieved despite low homeowner participation. Surveys indicate that many residents viewed stormwater as the city's problem and had negative perceptions of green infrastructure, despite slightly pro-environment values generally. Overall, this study demonstrates green infrastructure's hydrological effectiveness but raises challenging questions about overcoming social barriers retrofits at the neighborhood scale.

  20. 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.

  1. Modeling experimental stable isotope results from CO2 adsorption and diffusion experiments

    Science.gov (United States)

    Larson, T. E.

    2012-12-01

    steadily increased and became constant after two pore volumes of CO2 flushed through the column. Carbon and oxygen isotope values of the front of the peak (first pore volume) are 2‰ and 5‰ lower than the injected CO2 values, respectively. These results are fit very well using a mass transfer model that only includes binary diffusion between CO2 and helium that account for isotope substitution in the reduced mass coefficient. In contrast to these diffusion-dominated systems, CO2 break through curves from the illite packed column show strong adsorption effects that include a +180‰ increase in the carbon isotope ratio at the front of the peak followed by a 20‰ decrease. Up to 20 pore volumes of CO2 were flushed through the column before the carbon and oxygen isotope values stabilized to their starting values. These adsorption effects cannot be modeled using mass isotope effects alone, and instead must include additional parameters such as volume effects. These results demonstrate the importance of understanding the isotopic effects of CO2 in different substrates, and potentially offers a tracer tool that can be used to quantify surface area, transport distance, and surface reactivity of CO2. Additional applications may include more affectively determining transfer rates of CO2 across low permeability zones.

  2. Experimental and Numerical Modeling of Fluid Flow Processes in Continuous Casting: Results from the LIMMCAST-Project

    Science.gov (United States)

    Timmel, K.; Kratzsch, C.; Asad, A.; Schurmann, D.; Schwarze, R.; Eckert, S.

    2017-07-01

    The present paper reports about numerical simulations and model experiments concerned with the fluid flow in the continuous casting process of steel. This work was carried out in the LIMMCAST project in the framework of the Helmholtz alliance LIMTECH. A brief description of the LIMMCAST facilities used for the experimental modeling at HZDR is given here. Ultrasonic and inductive techniques and the X-ray radioscopy were employed for flow measurements or visualizations of two-phase flow regimes occurring in the submerged entry nozzle and the mold. Corresponding numerical simulations were performed at TUBAF taking into account the dimensions and properties of the model experiments. Numerical models were successfully validated using the experimental data base. The reasonable and in many cases excellent agreement of numerical with experimental data allows to extrapolate the models to real casting configurations. Exemplary results will be presented here showing the effect of electromagnetic brakes or electromagnetic stirrers on the flow in the mold or illustrating the properties of two-phase flows resulting from an Ar injection through the stopper rod.

  3. The force-length relationship of a muscle-tendon complex : experimental results and model calculations

    NARCIS (Netherlands)

    Bobbert, Maarten F.; Ettema, Gertjan C.; Huijing, Peter A.

    1990-01-01

    Models are useful when studying how architectural and physiological properties of muscle-tendon complexes are related to function, because they allow for the simulation of the behaviour of such complexes during natural movements. In the construction of these models, evaluation of their accuracy is

  4. Bioimpedance measurements in dentistry to detect inflammation: numerical modelling and experimental results.

    Science.gov (United States)

    Cosoli, G; Scalise, L; Tricarico, G; Russo, P; Cerri, G

    2017-06-01

    Bioimpedance measurements represent an advantageous method to evaluate the physio-pathological conditions of biological tissues and their use is spreading in different application fields, from the evaluation of body composition to the vital signs monitoring, passing through the individuation of cancer tissues and the detection of different substances (e.g. glucose measurements in people affected by diabetes). In fact, tissues electric properties vary with their conditions; for example, electrical conductivity increases when there is an inflammatory process, because of the presence of oedema, hyperaemia and infiltration. Inflammatory phenomena are frequent in dentistry, in diseases like periodontitis and peri-implantitis; however, at present the diagnosis is mainly done with the naked eye, by observing the gingiva redness and swelling. The aim of this work is to prove the feasibility of the inflammation detection by means of bioimpedance measurements. Both numerical simulations and preliminary experimental measurements provide significant outcomes in differentiating between healthy and inflamed tissues. Percentage differences in the impedance modulus equal to 4-20% (numerical simulations) and 35-56% (experimental measurements), respectively, depending on the considered conditions (e.g. electrodes characteristics and inflammation severity), were found. Such a measure could be integrated in electromedical devices designed, for example, for the therapy of peri-implantitis, in order to personalise the therapeutic dose in terms of intensity and duration and focusing it on the impaired area, minimising the effects on the surrounding tissues.

  5. Micronozzles: 3D numerical structural and gas dynamics modeling, fabrication, and preliminary experimental results

    Science.gov (United States)

    Borovkov, Alexei I.; Pyatishev, Evgenij N.; Lurie, Mihail S.; Korshunov, Andrey V.; Akulshin, Y. D.; Dolganov, A. G.; Sabadash, V. O.

    2001-02-01

    The tiny engines, founded on the principle of reactive thrust, are one of most perspective actuators developed by modern micromechanics. These engines can be applied for such apparent problems, as orientation and stabilization of small space objects, but also as local or distributed reactive thrust of new phylum of aerospace objects, for control of boundary layer of flying objects and in series of converting power devices of different purposes. Distinctive features of jet tiny engines are profitability (very large thrust-to-weight ratio) and high (milliseconds) response, which makes them to irreplaceable elements in control systems and, specially, in distributed power generations. These features are provided the minimum sizes, high pressure in working chambers and hypersonic velocity of propulsive jet. Topologically micronozzles are designed as the flat batch devices (3 layers as minimum). The lower and upper layers make flat walls of the nozzle and mainly influence on strength properties of the device. The mean layer reshapes geometry and determines gas dynamic characteristic of the nozzle. A special problem is the opening-up of the combustion-mixture, which is not esteemed in this work. It is necessary to allow for effect of considerable local stresses arising at the expense of static and dynamic loading at design of the jet tiny engines. Thermal gas dynamic processes in the chamber and nozzle determine the values and nature of these stresses, which are hardly studied for the microdevices. The priority is mathematical and experimental simulation of these processes. The most suitable object for initial phase of experimental simulation is the 'cold' engine. The demanded chamber static pressure is formed by external compressed air. In Laboratory of Microtechnology and MicroElectroMechanical Systems a number of such tiny engines with different shapes of the chamber's and the nozzles' surfaces were designed, made and tested. The engines were produced from photosensing

  6. Emanation thermal analysis study of synthetic gibbsite - Evaluation of experimental ETA results by mathematical modelling

    Czech Academy of Sciences Publication Activity Database

    Balek, Vladimír; Šubrt, Jan; Rouquerol, J.; Llewellyn, P.; Zeléňák, V.; Bountsewa, I. M.; Beckman, I. N.; Györyová, K.

    2003-01-01

    Roč. 71, č. 3 (2003), s. 773-782 2003 ISSN 1388-6150 R&D Projects: GA MŠk LN00A028; GA MŠk ME 344 Institutional research plan: CEZ:AV0Z4032918 Keywords : ETA * gibbsite * mathematical modelling Subject RIV: CA - Inorganic Chemistry Impact factor: 1.094, year: 2003

  7. Experimental Results and Integrated Modeling of Bacterial Growth on an Insoluble Hydrophobic Substrate (Phenanthrene)

    DEFF Research Database (Denmark)

    Adam, Iris K. U.; Rein, Arno; Miltner, Anja

    2014-01-01

    Metabolism of a low-solubility substrate is limited by dissolution and availability and can hardly be determined. We developed a numerical model for simultaneously calculating dissolution kinetics of such substrates and their metabolism and microbial growth (Monod kinetics with decay) and tested ...

  8. Modeling and experimental results for condensing supercritical CO2 power cycles.

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Steven Alan; Conboy, Thomas M.; Radel, Ross F.; Rochau, Gary Eugene

    2011-01-01

    This Sandia supported research project evaluated the potential improvement that 'condensing' supercritical carbon dioxide (S-CO{sub 2}) power cycles can have on the efficiency of Light Water Reactors (LWR). The analytical portion of research project identified that a S-CO{sub 2} 'condensing' re-compression power cycle with multiple stages of reheat can increase LWR power conversion efficiency from 33-34% to 37-39%. The experimental portion of the project used Sandia's S-CO{sub 2} research loop to show that the as designed radial compressor could 'pump' liquid CO{sub 2} and that the gas-cooler's could 'condense' CO{sub 2} even though both of these S-CO{sub 2} components were designed to operate on vapor phase S-CO{sub 2} near the critical point. There is potentially very high value to this research as it opens the possibility of increasing LWR power cycle efficiency, above the 33-34% range, while lowering the capital cost of the power plant because of the small size of the S-CO{sub 2} power system. In addition it provides a way to incrementally build advanced LWRs that are optimally designed to couple to S-CO{sub 2} power conversion systems to increase the power cycle efficiency to near 40%.

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

    International Nuclear Information System (INIS)

    Charles, M.; Lemaignan, C.

    1992-01-01

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

  10. Surgical treatment of cerebral ischemia by means of diode laser: first experimental results and comparison with theoretical model

    Science.gov (United States)

    Signorelli, C. D.; Giaquinta, A.; Iofrida, G.; Donato, G.; Signorelli, Fr.; Bellecci, C.; Lo Feudo, T.; Gaudio, P.; Gelfusa, M.

    2007-07-01

    In the present paper feasibility and potential advantages of using diode laser for surgical treatment of cerebral ischemia and intracranial aneurysms will be evaluated. At this purpose non linear mathematical model was developed and experimentally validated to investigate the effects of the changes in tissue physical properties, in terms of operating time, tensile strength and tissue damage during medical laser application. The numerical simulations have been carried on by a finite-elements based software package (FEMLAB). In vitro results of human saphenous veins of inferior limbs (n=55) after 799 nm diode laser soldering, combined with an indocyanine green-enhanced, will be presented. The simulations results and their comparison with experimental measurements will be reported.

  11. A comparison between experimental results and a mathematical model of the oxidation reactions induced by radiation of ferrous ions

    International Nuclear Information System (INIS)

    Sanchez-Mejorada, G.; Frias, D.; Negron-Mendoza, A.; Ramos-Bernal, S.

    2008-01-01

    The dependence of the response of chemical dosimeters as a function of the irradiation temperature is an important issue that has not yet been addressed within a mathematical modeling framework. The temperature dependence of the dose-response function has to be taken into account in practical applications, mainly in frozen food sterilization by radiation. Significant errors may occur if the dependence of the dosimeter response on the irradiation temperature is not taken into account properly. The experimental results obtained irradiating iron salt solutions at different temperatures below and above 0 deg. C show that the change in the valence of Fe 2+ as a function of dose are linear for both liquid and frozen solutions. This led us to conclude that the iron salt solution seems suitable for low-temperature applications having a linear dose-response up to 600 Gy, despite a progressive decrease of sensitivity as temperature decreases. A nonlinear differential model for the kinetics of reactions induced by radiation in iron salt solutions was established. In the model a temperature correction factor was included in order to take into account abrupt changes observed in the kinetics of the chemical process when the irradiated solution's allotropic phase changes from liquid to solid (ice). Fitting the kinetic model to the experimental results at different temperatures we found the temperature correction factors

  12. Experimental irradiation of UMo fuel: Pie results and modeling of fuel behaviour

    International Nuclear Information System (INIS)

    Languille, A.; Plancq, D.; Huet, F.; Guigon, B.; Lemoine, P.; Sacristan, P.; Hofman, G.; Snelgrove, J.; Rest, J.; Hayes, S.; Meyer, M.; Vacelet, H.; Leborgne, E.; Dassel, G.

    2002-01-01

    Seven full-sized U Mo plates containing ca. 8 g/cm 3 of uranium in the fuel meat have been irradiated since the beginning of the French U Mo development program. The first three of them with 20% 235 U enrichment were irradiated at maximum surfacic power under 150 W/cm 2 in the OSIRIS reactor up to 50% burn-up and are under examination. Their global behaviour is satisfactory: no failure and a low swelling. The other four plates were irradiated in the HFR Petten at maximum surfacic power between 150 and 250 W/cm 2 with two enrichments 20 and 35%. The experiment was stopped after two cycles due to a fuel failure. The post- irradiation examinations were completed in 2001 in Petten. Examinations showed a correct behaviour of 20% enriched plates and an abnormal behaviour of the two other plates (35%-enriched) with a clad failure on the plate 4. The fuel failure appears to result from a combination of factors that led to high corrosion cladding and high fuel meat temperatures. (author)

  13. Model for diffusion and porewater chemistry in compacted bentonite. Experimental arrangements and preliminary results of the porewater chemistry studies

    International Nuclear Information System (INIS)

    Muurinen, A.; Lehikoinen, J.

    1997-01-01

    This report describes the progress of the experimental research on the porewater chemistry in bentonite. The research is part of the project Microstructural and chemical parameters of bentonite as determinants of waste isolation efficiency within the Nuclear Fission Safety Program organized by The Commission of the European Communities. The study was started by a literature overview on the properties of bentonite, porewater-sampling methods and obtained results. On the basis of the literature study, porewater extraction by squeezing seemed the most promising method for further development. The apparatus developed in this study consists of a pressing apparatus, which is used to create the necessary long-term compression, and of the compaction cell where porewater is separated from bentonite and collected in a syringe. The constant log-term force is maintained by a strong spring. An experimental study of solution-bentonite interactions was initiated. The parameters varied are the bentonite density, bentonite-water ratio, composition of the solutions, and the composition of bentonite. The report presents the experimental arrangements, the preliminary results for studying the evolution of water chemistry and the results of pre-modelling. (orig.) (27 refs.)

  14. ASTRID: A 3D Eulerian software for subcooled boiling modelling - comparison with experimental results in tubes and annuli

    Energy Technology Data Exchange (ETDEWEB)

    Briere, E.; Larrauri, D.; Olive, J. [Electricite de France, Chatou (France)

    1995-09-01

    For about four years, Electricite de France has been developing a 3-D computer code for the Eulerian simulation of two-phase flows. This code, named ASTRID, is based on the six-equation two-fluid model. Boiling water flows, such as those encountered in nuclear reactors, are among the main applications of ASTRID. In order to provide ASTRID with closure laws and boundary conditions suitable for boiling flows, a boiling model has been developed by EDF and the Institut de Mecanique des Fluides de Toulouse. In the fluid, the heat and mass transfer between a bubble and the liquid is being modelled. At the heating wall, the incipient boiling point is determined according to Hsu`s criterion and the boiling heat flux is split into three additive terms: a convective term, a quenching term and a vaporisation term. This model uses several correlations. EDF`s program in boiling two-phase flows also includes experimental studies, some of which are performed in collaboration with other laboratories. Refrigerant subcooled boiling both in tubular (DEBORA experiment, CEN Grenoble) and in annular geometry (Arizona State University Experiment) have been computed with ASTRID. The simulations show the satisfactory results already obtained on void fraction and liquid temperature. Ways of improvement of the model are drawn especially on the dynamical part.

  15. ASTRID: A 3D Eulerian software for subcooled boiling modelling - comparison with experimental results in tubes and annuli

    International Nuclear Information System (INIS)

    Briere, E.; Larrauri, D.; Olive, J.

    1995-01-01

    For about four years, Electricite de France has been developing a 3-D computer code for the Eulerian simulation of two-phase flows. This code, named ASTRID, is based on the six-equation two-fluid model. Boiling water flows, such as those encountered in nuclear reactors, are among the main applications of ASTRID. In order to provide ASTRID with closure laws and boundary conditions suitable for boiling flows, a boiling model has been developed by EDF and the Institut de Mecanique des Fluides de Toulouse. In the fluid, the heat and mass transfer between a bubble and the liquid is being modelled. At the heating wall, the incipient boiling point is determined according to Hsu's criterion and the boiling heat flux is split into three additive terms: a convective term, a quenching term and a vaporisation term. This model uses several correlations. EDF's program in boiling two-phase flows also includes experimental studies, some of which are performed in collaboration with other laboratories. Refrigerant subcooled boiling both in tubular (DEBORA experiment, CEN Grenoble) and in annular geometry (Arizona State University Experiment) have been computed with ASTRID. The simulations show the satisfactory results already obtained on void fraction and liquid temperature. Ways of improvement of the model are drawn especially on the dynamical part

  16. Experimental investigation and modelling of surface roughness and resultant cutting force in hard turning of AISI H13 Steel

    Science.gov (United States)

    Boy, M.; Yaşar, N.; Çiftçi, İ.

    2016-11-01

    In recent years, turning of hardened steels has replaced grinding for finishing operations. This process is compared to grinding operations; hard turning has higher material removal rates, the possibility of greater process flexibility, lower equipment costs, and shorter setup time. CBN or ceramic cutting tools are widely used hard part machining. For successful application of hard turning, selection of suitable cutting parameters for a given cutting tool is an important step. For this purpose, an experimental investigation was conducted to determine the effects of cutting tool edge geometry, feed rate and cutting speed on surface roughness and resultant cutting force in hard turning of AISI H13 steel with ceramic cutting tools. Machining experiments were conducted in a CNC lathe based on Taguchi experimental design (L16) in different levels of cutting parameters. In the experiments, a Kistler 9257 B, three cutting force components (Fc, Ff and Fr) piezoelectric dynamometer was used to measure cutting forces. Surface roughness measurements were performed by using a Mahrsurf PS1 device. For statistical analysis, analysis of variance has been performed and mathematical model have been developed for surface roughness and resultant cutting forces. The analysis of variance results showed that the cutting edge geometry, cutting speed and feed rate were the most significant factors on resultant cutting force while the cutting edge geometry and feed rate were the most significant factor for the surface roughness. The regression analysis was applied to predict the outcomes of the experiment. The predicted values and measured values were very close to each other. Afterwards a confirmation tests were performed to make a comparison between the predicted results and the measured results. According to the confirmation test results, measured values are within the 95% confidence interval.

  17. Fly's proprioception-inspired micromachined strain-sensing structure: idea, design, modeling and simulation, and comparison with experimental results

    Science.gov (United States)

    Wicaksono, D. H. B.; Zhang, L.-J.; Pandraud, G.; French, P. J.; Vincent, J. F. V.

    2006-04-01

    A new strain-sensing structure inspired from insect's (especially the Fly) propricoception sensor is devised. The campaniform sensillum is a strain-sensing microstructure with very high sensitivity despite its small dimension (diameter ~10 µm in a relatively stiff material of insect's exocuticle (E = ~109 Pa). Previous work shows that the high sensitivity of this structure towards strain is due to its membrane-in-recess- and strainconcentrating- hole- features. Based on this inspiration, we built similar structure using silicon micromachining technology. Then a simple characterisation setup was devised. Here, we present briefly, finite-element modeling and simulation based on this actual sample preparation for the characterisation. As comparison and also to understand mechanical features responsible for the strain-sensitivity, we performed the modeling on different mechanical structures: bulk chunk, blind-hole, thorugh-hole, surface membrane, and membrane-in-recess. The actual experimental characterisation was performed previously using optical technique to membranein- recess micromachined Si structure. The FEM simulation results confirm that the bending stress and strain are concentrated in the hole-vicinity. The membrane inside the hole acts as displacement transducer. The FEM is in conformity with previous analytical results, as well as the optical characterisation result. The end goal is to build a new type MEMS strain sensor.

  18. HYDROïD humanoid robot head with perception and emotion capabilities :Modeling, Design and Experimental Results

    Directory of Open Access Journals (Sweden)

    Samer eAlfayad

    2016-04-01

    Full Text Available In the framework of the HYDROïD humanoid robot project, this paper describes the modeling and design of an electrically actuated head mechanism. Perception and emotion capabilities are considered in the design process. Since HYDROïD humanoid robot is hydraulically actuated, the choice of electrical actuation for the head mechanism addressed in this paper is justified. Considering perception and emotion capabilities leads to a total number of 15 degrees of freedom for the head mechanism which are split on four main sub-mechanisms: the neck, the mouth, the eyes and the eyebrows. Biological data and kinematics performances of human head are taken as inputs of the design process. A new solution of uncoupled eyes is developed to possibly address the master-slave process that links the human eyes as well as vergence capabilities. Modeling each sub-system is carried out in order to get equations of motion, their frequency responses and their transfer functions. The neck pitch rotation is given as a study example. Then, the head mechanism performances are presented through a comparison between model and experimental results validating the hardware capabilities. Finally, the head mechanism is integrated on the HYDROïD upper-body. An object tracking experiment coupled with emotional expressions is carried out to validate the synchronization of the eye rotations with the body motions.

  19. Experimental and modeling results of creep fatigue life of Inconel 617 and Haynes 230 at 850 C

    International Nuclear Information System (INIS)

    Chen, Xiang; Sokolov, Mikhail A.; Sham, Sam; Erdman, Donald L. III; Busby, Jeremy T.; Mo, Kun; Stubbins, James

    2013-01-01

    Creep fatigue testing of Ni-based superalloy Inconel 617 and Haynes 230 were conducted in the air at 850 C. Tests were performed with fully reversed axial strain control at a total strain range of 0.5%, 1.0% or 1.5% and hold time at maximum tensile strain for 3, 10 or 30 min. In addition, two creep fatigue life prediction methods, i.e. linear damage summation and frequency-modified tensile hysteresis energy modeling, were evaluated and compared with experimental results. Under all creep fatigue tests, Haynes 230 performed better than Inconel 617. Compared to the low cycle fatigue life, the cycles to failure for both materials decreased under creep fatigue test conditions. Longer hold time at maximum tensile strain would cause a further reduction in both material creep fatigue life. The linear damage summation could predict the creep fatigue life of Inconel 617 for limited test conditions, but considerably underestimated the creep fatigue life of Haynes 230. In contrast, frequency-modified tensile hysteresis energy modeling showed promising creep fatigue life prediction results for both materials.

  20. Experimental results on evaporation waves

    Science.gov (United States)

    Grana Otero, Jose; Parra Fabian, Ignacio

    2010-11-01

    A liquid contained in a vertical glass tube is suddenly depressurized from a high initial pressure down to one for which the stable state is vapour, so vaporization sets off at the free surface. For large enough evaporation rates, the planar vapour-liquid interface is Darrieus-Landau unstable [1], leading to the interface surface rippling close to the instability threshold. Further increasing the initial to final pressure ratio brings about evaporation waves [2,3], in which a highly corrugated front propagates downwards into the liquid. A new experimental method is presented as well as some experimental results obtained by tracking the evolution of the front with a high speed camera. In addition, a number of new phenomena related to the dynamics of bubbles growth at the walls has been uncovered. In particular, a new mode of propagation of the evaporation front is found. In this mode the front originates from below the interface, so the propagation is upwards against gravity with a curved but smooth front.[4pt] [1] F. J. Higuera, Phys. Fluids, V. 30, 679 (1987).[0pt] [2] J.E.Shepherd and B.Sturtevant, J.Fluid Mech., V.121,379 (1982).[0pt] [3] P.Reinke and G.Yadigaroglu, Int.J.Multiph. Flow, V.27,1487 (2001).

  1. CFD approach to modelling, hydrodynamic analysis and motion characteristics of a laboratory underwater glider with experimental results

    Directory of Open Access Journals (Sweden)

    Yogang Singh

    2017-06-01

    Full Text Available Underwater gliders are buoyancy propelled vehicle which make use of buoyancy for vertical movement and wings to propel the glider in forward direction. Autonomous underwater gliders are a patented technology and are manufactured and marketed by corporations. In this study, we validate the experimental lift and drag characteristics of a glider from the literature using Computational fluid dynamics (CFD approach. This approach is then used for the assessment of the steady state characteristics of a laboratory glider designed at Indian Institute of Technology (IIT Madras. Flow behaviour and lift and drag force distribution at different angles of attack are studied for Reynolds numbers varying from 105 to 106 for NACA0012 wing configurations. The state variables of the glider are the velocity, gliding angle and angle of attack which are simulated by making use of the hydrodynamic drag and lift coefficients obtained from CFD. The effect of the variable buoyancy is examined in terms of the gliding angle, velocity and angle of attack. Laboratory model of glider is developed from the final design asserted by CFD. This model is used for determination of static and dynamic properties of an underwater glider which were validated against an equivalent CAD model and simulation results obtained from equations of motion of glider in vertical plane respectively. In the literature, only empirical approach has been adopted to estimate the hydrodynamic coefficients of the AUG that are required for its trajectory simulation. In this work, a CFD approach has been proposed to estimate the hydrodynamic coefficients and validated with experimental data. A two-mass variable buoyancy engine has been designed and implemented. The equations of motion for this two-mass engine have been obtained by modifying the single mass version of the equations described in the literature. The objectives of the present study are to understand the glider dynamics adopting a CFD approach

  2. Thermal, chemical, and mass transport processes induced in abyssal sediments by the emplacement of nuclear wastes: Experimental and modelling results

    International Nuclear Information System (INIS)

    McVey, D.F.; Erickson, K.L.; Seyfried, W.E. Jr.

    1983-01-01

    In this chapter the authors discuss the current status of heat and mass transport studies in the marine red clay sediments that are being considered as a nuclear waste isolation medium and review analytical and experimental studies. Calculations based on numerical models indicate that for a maximum allowable sediment-canister interface temperatures of 200 0 to 250 0 C, the sediment can absorb about 1.5kW initial power from waste buried 30 m in the sediment in a canister that is 3 m long and 0.3 m in diameter. The resulting fluid displacement due to convections is found to be small, less than 1 m. Laboratory studies of the geochemical effects induced by heating sediment-seawater mixtures indicate that the canister and waste form should be designed to resist a hot, relatively acidic oxidizing environment. Since the thermally altered sediment volume of about 5.5 m/sup 3/ is small relative to the sediment volume overlying the canister, the acid and oxidizing conditions should significantly affect the properties of the far field only if thermodiffusional process (Soret effect) prove to be significant. If thermodiffusional effects are important, however, near-field chemistry will differ considerably from that predicted from results of constant temperature sediment-seawater interaction experiments

  3. The influence of melatonin and agomelatine on urodynamic parameters in experimental overactive bladder model – preliminary results

    Directory of Open Access Journals (Sweden)

    Łukasz Dobrek

    2011-11-01

    Full Text Available Introduction:Overactive bladder (OAB is a common disease entity with complex pathogenesis that involves neurogenic, myogenic and abnormal paracrine urothelial activity mechanisms. Our objective was to estimate bladder functioning in urodynamic studies in experimental, both acute (AOAB and chronic (COAB cyclophosphamide (CYP-evoked OAB model in response to melatonin (MLT; antioxidant and MT receptor agonist or agomelatine (AMT; MT receptor agonist and 5HT2C receptor antagonist.Material/Methods:Seven groups were studied: 1 – control, 2–4 – MLT treated AOAB and COAB rats, 5–7 – AMT treated AOAB and COAB rats. AOAB model was evoked by single CYP administration (IP 200 mg/kg body weight, while COAB one was induced by a four-time administration of CYP (IP 75 mg/kg body weight. Each group underwent urethane anesthesia to perform urodynamic recordings in resting conditions and after administration 50 (group 2 or 5, 75 (group 3 or 6 or 100 mg/kg (group 4 or 7 of melatonin (groups 2–4 or agomelatine (groups 5–7, followed by classical urodynamic parameters assessment.Results:Neither melatonin nor agomelatine did not affect urodynamic parameters in the AOAB rats. In COAB model, after 75 and 100 mg/kg of MLT we revealed an improvement in urodynamic parameters. AMT (75 and 100 mg/kg administration caused deterioration of urodynamic findings suggesting bladder overactivity exacerbation.Disscussion:In summary, melatonin ameliorates bladder overactivity in cyclophosphamide-induced COAB. Agomelatine, contrary to melatonin, aggravates bladder dysfunction in this group. These findings suggest that the improvement in urodynamic parameters after melatonin administration may be due to its antioxidative profile and is not related to MT receptors activation. However, agomelatine’s unfavorable action on the bladder, resulting in its overactivity in COAB group, may not only be the result of MT receptor activation without the concomitant antioxidative

  4. Comparison of modelling and experimental results of anode surface melting by femtosecond laser-stimulated electrical discharges in small gaps

    International Nuclear Information System (INIS)

    Chen Jian; He Lingna; Farson, Dave F; Rokhlin, Stanislav I

    2011-01-01

    Experiments and particle-in-cell simulations of femtosecond laser-stimulated electrical discharges in submicrometre gaps between scanning tunnelling microscope tip cathodes and gold film anodes are described. In experiments at applied potentials of 35 V and less, discharges were detected either as self-terminating low-current pulses with durations less than 10 ns and magnitudes less than 200 mA or as higher-current, longer-duration current waveforms. The probability of occurrence of low-current pulses increased as applied potential was decreased, being certain at low potentials of 20-25 V. Low-current pulse waveforms and surface melting of gold anodes predicted by the simulations were compared with experiments. Laser stimulation was modelled by introducing partially ionized electrode materials into the simulation domain at a controlled rate. Simulation results showed that the duration of low-current pulses was influenced by the time over which material was added to the gap region, establishing the importance of electrode vaporization on discharge duration. Subsequently, partially ionized electrode materials were preloaded into the gap in controlled amounts in subsequent simulations. Peak currents predicted by these simulations were nearly equal to the low-current pulse measurements but simulated pulse durations were shorter than experiments. Thus, the time axis of simulation current profiles was normalized for equality of charge transfer with experiments. Anode temperatures and melt diameters calculated from normalized simulated heat input profiles were well matched to experimental measurements.

  5. Doppler method leak detection for LMFBR steam generators. Pt. 1. Experimental results of bubble detection using small models

    International Nuclear Information System (INIS)

    Kumagai, Hiromichi

    1999-01-01

    To prevent the expansion of the tube damage and to maintain structural integrity in the steam generators (SGs) of fast breeder reactors (FBRs), it is necessary to detect precisely and immediately the leakage of water from heat transfer tubes. Therefore, an active acoustic method was developed. Previous studies have revealed that in practical steam generators the active acoustic method can detect bubbles of 10 l/s within 10 seconds. To prevent the expansion of damage to neighboring tubes, it is necessary to detect smaller leakages of water from the heat transfer tubes. The Doppler method is designed to detect small leakages and to find the source of the leak before damage spreads to neighboring tubes. To evaluate the relationship between the detection sensitivity of the Doppler method and the bubble volume and bubble size, the structural shapes and bubble flow conditions were investigated experimentally, using a small structural model. The results show that the Doppler method can detect the bubbles under bubble flow conditions, and it is sensitive enough to detect small leakages within a short time. The doppler method thus has strong potential for the detection of water leakage in SGs. (author)

  6. Polymer-coated compliant receivers for intact laser-induced forward transfer of thin films: experimental results and modelling

    Science.gov (United States)

    Feinaeugle, Matthias; Horak, Peter; Sones, Collin L.; Lippert, Thomas; Eason, Rob W.

    2014-09-01

    In this study, we investigate both experimentally and numerically laser-induced forward transfer (LIFT) of thin films to determine the role of a thin polymer layer coating the receiver with the aim of modifying the rate of deceleration and reduction of material stress preventing intact material transfer. A numerical model of the impact phase during LIFT shows that such a layer reduces the modelled stress. The evolution of stress within the transferred deposit and the substrate as a function of the thickness of the polymer layer, the transfer velocity and the elastic properties of the polymer are evaluated. The functionality of the polymer layer is verified experimentally by LIFT printing intact 1- m-thick bismuth telluride films and polymeric light-emitting diode pads onto a layer of 12-m-thick polydimethylsiloxane and 50-nm-thick poly(3,4-ethylenedioxythiophene) blended with poly(styrenesulfonate) (PEDOT:PSS), respectively. Furthermore, it is demonstrated experimentally that the introduction of such a compliant layer improves adhesion between the deposit and its substrate.

  7. Description of premixing with the MC3D code including molten jet behavior modeling. Comparison with FARO experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Berthoud, G.; Crecy, F. de; Meignen, R.; Valette, M. [CEA-G, DRN/DTP/SMTH, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)

    1998-01-01

    The premixing phase of a molten fuel-coolant interaction is studied by the way of mechanistic multidimensional calculation. Beside water and steam, corium droplet flow and continuous corium jet flow are calculated independent. The 4-field MC3D code and a detailed hot jet fragmentation model are presented. MC3D calculations are compared to the FARO L14 experiment results and are found to give satisfactory results; heat transfer and jet fragmentation models are still to be improved to predict better final debris size values. (author)

  8. TMX-U experimental results

    International Nuclear Information System (INIS)

    Simonen, T.C.; Allen, S.L.; Casper, T.A.

    1983-01-01

    This paper describes results from the Tandem Mirror Experiment-Upgrade (TMX-U). Mirror-confined electrons with 30 to 70 keV mean energy densities of 0.5 to 2.0 x 10 12 cm -3 and average betas of 3 to 5% are produced using electron-cyclotron resonant heating (ECRH). These results are consistent with an electron Fokker-Planck code. Improved ion-cyclotron microstability is observed using neutral beam injection at 47 0 to the magnetic axis, rather than at 90 0 as in the previous experiment, TMX. Strong end plugging has been produced using a combination of ECRH gyrotrons with sloshing-ion beam injection. In these low-density central cell experiments (3 x 10 11 cm -3 ) the axial losses (tau/sub parallel/ = 20 to 80 ms) are smaller than the nonambipolar radial losses (tau/sub perpendicular/ = 4 to 8 ms). Plugging has been achieved with a central cell density double that of the end plugs. Although no direct measurements are yet available to determine if a thermal barrier potential dip is generated, these experiments support many theoretical features of the thermal barrier concept

  9. Electrostatic Properties of PE and PTFE Subjected to Atmospheric Pressure Plasma Treatment; Correlation of Experimental Results with Atomistic Modeling

    Science.gov (United States)

    Trigwell, Steve; Boucher, Derrick; Calle, Carlos

    2006-01-01

    The use of an atmospheric pressure glow discharge (APGD) plasma was used at KSC to increase the hydrophilicity of spaceport materials to enhance their surface charge dissipation and prevent possible ESD in spaceport operations. Significant decreases in charge decay times were observed after tribocharging the materials using the standard KSC tribocharging test. The polarity and amount of charge transferred was dependent upon the effective work function differences between the respective materials. In this study, polyethylene (PE) and polytetrafluoroethylene (PTFE) were exposed to a He+O2 APGD. The pre and post treatment surface chemistry was analyzed by X-ray photoelectron spectroscopy and contact angle measurements. Semi-empirical and ab initio calculations were performed to correlate the experimental results with some plausible molecular and electronic structure features of the oxidation process. For the PE, significant surface oxidation was observed, as indicated by XPS showing C-O, C=O, and O-C=O bonding, and a decrease in the surface contact angle from 98.9 deg to 61.2 deg. For the PTFE, no C-O bonding appeared and the surface contact angle increased indicating the APGD only succeeded in cleaning the PTFE surface without affecting the surface structure. The calculations using the PM3 and DFT methods were performed on single and multiple oligomers to simulate a wide variety of oxidation scenarios. Calculated work function results suggest that regardless of oxidation mechanism, e.g. -OH, =0 or a combination thereof, the experimentally observed levels of surface oxidation are unlikely to lead to a significant change in the electronic structure of PE and that its increased hydrophilic properties are the primary reason for the observed changes in its electrostatic behavior. The calculations for PTFE argue strongly against significant oxidation of that material, as confirmed by the XPS results.

  10. Calcium and phosphate effects on growth and alkaloid production in Coffea arabica: experimental results and mathematical model.

    Science.gov (United States)

    Bramble, J L; Graves, D J; Brodelius, P

    1991-04-15

    Plant, mammalian, and microbial cells are commonly immobilized in calcium alginate gels for the production of valuable secondary metabolites. However, calcium ions are known to inhibit growth in various types of cells, and calcium is an integral part of such gels. Therefore, an investigation was conducted to evaluate the effect of calcium on the growth and alkaloid production of a model cell-line, Coffea arabica, in suspension culture before, attempting to immobilize such cells in alginate. A kinetic model was then developed from the results to describe cell growth and alkaloid production and the mechanism by which calcium influences these variables. In addition, it was observed that there was a characteristic relationship between the concentration of calcium in the external medium and the concentration of extra cellular and intracellular phosphate. The intracellular phosphate level was, in turn, related to the production of alkaloids. Using these results, a dynamic mathematical model of cell growth and alkaloid production was developed based on the proposed roles of calcium and phosphate. The model showed satisfactory agreement with three sets of experiments at different calcium concentrations. A possible linkage between the calcium and phosphate results is postulated based on the limited solubility of calcium phosphate.

  11. Caesium-137 and strontium-90 temporal series in the Tagus River: experimental results and a modelling study.

    Science.gov (United States)

    Miró, Conrado; Baeza, Antonio; Madruga, María J; Periañez, Raul

    2012-11-01

    The objective of this work consisted of analysing the spatial and temporal evolution of two radionuclide concentrations in the Tagus River. Time-series analysis techniques and numerical modelling have been used in this study. (137)Cs and (90)Sr concentrations have been measured from 1994 to 1999 at several sampling points in Spain and Portugal. These radionuclides have been introduced into the river by the liquid releases from several nuclear power plants in Spain, as well as from global fallout. Time-series analysis techniques have allowed the determination of radionuclide transit times along the river, and have also pointed out the existence of temporal cycles of radionuclide concentrations at some sampling points, which are attributed to water management in the reservoirs placed along the Tagus River. A stochastic dispersion model, in which transport with water, radioactive decay and water-sediment interactions are solved through Monte Carlo methods, has been developed. Model results are, in general, in reasonable agreement with measurements. The model has finally been applied to the calculation of mean ages of radioactive content in water and sediments in each reservoir. This kind of model can be a very useful tool to support the decision-making process after an eventual emergency situation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Competitive adsorption of arsenate and phosphate onto calcite; experimental results and modeling with CCM and CD-MUSIC

    Science.gov (United States)

    Sø, Helle Ugilt; Postma, Dieke; Jakobsen, Rasmus; Larsen, Flemming

    2012-09-01

    The competitive adsorption of arsenate and phosphate onto calcite was studied in batch experiments using calcite-equilibrated solutions. The solutions had circum-neutral pH (7-8.3) and covered a wide span in the activity of Ca2+ and CO32-. The results show that the adsorption of arsenate onto calcite is strongly reduced by the presence of phosphate, whereas phosphate adsorption is only slightly reduced by arsenate addition. Simultaneous and sequential addition (3 h apart) yields the same reduction in adsorption, underlining the high reversibility of the system. The reduction in adsorption of both arsenate and phosphate is most likely due to competition for the same sorption sites at the calcite surface, considering the similarity in sorption edges, pKa's and geometry of the two anions. The strong reduction in arsenate adsorption by competition with phosphate suggests that adsorption of arsenate onto calcite is of minor importance in most groundwater aquifers, as phosphate is often present at concentration levels sufficient to significantly reduce arsenate adsorption. The CD-MUSIC model for calcite was used successfully to model adsorption of arsenate and phosphate separately. By combining the models for single sorbate systems the competitive adsorption of phosphate and arsenate onto calcite in the binary system could be predicted. This is in contrast to the constant capacitance model (CCM) which under-predicted the competition when combining the models for single sorbate systems. This study clearly shows the importance of performing competitive adsorption studies for validation of multi-component models and for estimating the mobility of an ion in the environment.

  13. Experimental Results and Modeling of Low-Heat-Capacity TES Microcalorimeters for Soft-X-ray Spectroscopy

    Science.gov (United States)

    Eckart, Megan E.; Adams, Joseph S.; Bandler, Simon R.; Brekosky, Regis P.; Chervenak, James A.; Finkbeiner, Fred M.; Kelley, Richard L.; Kilbourne, Caroline A.; Scott Porter, F.; Sadleir, John E.; Smith, Stephen J.

    2009-12-01

    Transition-edge-sensor (TES) X-ray microcalorimeters have mostly been targeted at mid-band energies from 0.05-10 keV and high energies to above 100 keV. However, many other optimizations are possible. Here we present results from devices optimized for soft X-ray applications. For spectroscopy below 1 keV, the X-ray stopping power and heat capacity (C) of the TES itself are high enough that we can omit a separate absorber. The resulting devices have low C and the best-achievable energy resolution should be under 1 eV. We are interested in pursuing such devices primarily for astrophysical applications and laboratory astrophysics at LLNL's Electron-Beam Ion Trap. To this end, we have studied arrays in which `bare' TESs are interspersed with broad-band pixels that have absorbers. By extending the absorbers to cover the area where the leads contact the low-energy pixels, we have eliminated a significant source of non-Gaussian detector response. The bare devices are in a different regime from our typical devices in that C is ten times lower and the conductance to the bath is four times lower. We have explored this regime through simultaneous fitting of noise and impedance data. These data cannot be fit by the simple model we employ to describe our typical broad-band devices. In this contribution we present X-ray spectra and the results from modeling.

  14. A 3D active-passive numerical skeletal muscle model incorporating initial tissue strains. Validation with experimental results on rat tibialis anterior muscle.

    Science.gov (United States)

    Grasa, J; Ramírez, A; Osta, R; Muñoz, M J; Soteras, F; Calvo, B

    2011-10-01

    This paper presents a three-dimensional finite element model of skeletal muscle and its validation incorporating inital tissue strains. A constitutive relation was determined by using a convex free strain energy function (SEF) where active and passive response contributions were obtained fitting experimental data from the rat tibialis anterior (TA) muscle. The passive and active finite strains response was modelled within the framework of continuum mechanics by a quasi-incompressible transversely isotropic material formulation. Magnetic resonance images (MRI) were obtained to reconstruct the external geometry of the TA. This geometry includes initial strains also taken into account in the numerical model. The numerical results show excellent agreement with the experimental results when comparing reaction force-extension curves both in passive and active tests. The proposed constitutive model for the muscle is implemented in a subroutine in the commercial finite element software package ABAQUS.

  15. Effects of stratocumulus, cumulus, and cirrus clouds on the UV-B diffuse to global ratio: Experimental and modeling results

    International Nuclear Information System (INIS)

    López, María Laura; Palancar, Gustavo G.; Toselli, Beatriz M.

    2012-01-01

    Broadband measurements of global and diffuse UV-B irradiance (280-315 nm) together with modeled and measured diffuse to global ratios (DGR) have been used to characterize the influence of different types of clouds on irradiance at the surface. Measurements were carried out during 2000-2001 in Córdoba City, Argentina. The Tropospheric Ultraviolet Visible (TUV) model was used to analyze the behavior of the modeled DGRs for different cloud optical depths and at different altitudes and solar zenith angles (SZA). Different cloud altitudes were also tested, although only the results for a cloud placed at 1.5-2.5 km of altitude are shown. A total of 16 day with stratocumulus, 12 with cumulus, and 16 with cirrus have been studied and compared among them and also against 21 clear sky days. Different behaviors were clearly detected and also differentiated through the analysis of the averages and the standard deviations of the DGRs: 1.02±0.06 for stratocumulus, 0.74±0.18 for cumulus, 0.63±0.12 for cirrus, and 0.60±0.13 for the clear sky days, respectively. Stratocumulus clouds showed a low variability in the DGR values, which were concentrated close to one at all SZAs. DGR values for cumulus clouds presented a large variability at all SZAs, mostly associated with the different optical depths. Finally, the closeness between the DGR values for cirrus clouds and the DGR values for clear days showed that these clouds generally do not strongly affect the UV-B irradiance at the surface at any SZA. In the opposite side, stratocumulus clouds were identified as those with the largest effects, at all SZAs, on the UV-B irradiance at the surface.

  16. TransCom model simulations of hourly atmospheric CO2: Experimental overview and diurnal cycle results for 2002

    NARCIS (Netherlands)

    Law, R. M.; Peters, W.; Roedenbeck, C.; Aulagnier, C.; Baker, I.; Bergmann, D. J.; Bousquet, P.; Brandt, J.; Bruhwiler, L.; Cameron-Smith, P. J.; Christensen, J. H.; Delage, F.; Denning, A. S.; Fan, S.; Geels, C.; Houweling, S.; Imasu, R.; Karstens, U.; Kawa, S. R.; Kleist, J.; Krol, M. C.; Lin, S. -J.; Lokupitiya, R.; Maki, T.; Maksyutov, S.; Niwa, Y.; Onishi, R.; Parazoo, N.; Patra, P. K.; Pieterse, G.; Rivier, L.; Satoh, M.; Serrar, S.; Taguchi, S.; Takigawa, M.; Vautard, R.; Vermeulen, A. T.; Zhu, Z.

    2008-01-01

    [1] A forward atmospheric transport modeling experiment has been coordinated by the TransCom group to investigate synoptic and diurnal variations in CO2. Model simulations were run for biospheric, fossil, and air-sea exchange of CO2 and for SF6 and radon for 2000-2003. Twenty-five models or model

  17. TransCom model simulations of hourly atmospheric CO2: Experimental overview and diurnal cycle results for 2002

    NARCIS (Netherlands)

    Law, R. M.; Peters, W.; RöDenbeck, C.; Aulagnier, C.; Baker, I.; Bergmann, D. J.; Bousquet, P.; Brandt, J.; Bruhwiler, L.; Cameron-Smith, P. J.; Christensen, J. H.; Delage, F.; Denning, A. S.; Fan, S.; Geels, C.; Houweling, S.; Imasu, R.; Karstens, U.; Kawa, S. R.; Kleist, J.; Krol, M. C.; Lin, S.-J.; Lokupitiya, R.; Maki, T.; Maksyutov, S.; Niwa, Y.; Onishi, R.; Parazoo, N.; Patra, P. K.; Pieterse, G.; Rivier, L.; Satoh, M.; Serrar, S.; Taguchi, S.; Takigawa, M.; Vautard, R.; Vermeulen, A. T.; Zhu, Z.

    2008-01-01

    A forward atmospheric transport modeling experiment has been coordinated by the TransCom group to investigate synoptic and diurnal variations in CO2. Model simulations were run for biospheric, fossil, and air-sea exchange of CO2 and for SF6 and radon for 2000-2003. Twenty-five models or model

  18. Experimental results showing the internal three-component velocity field and outlet temperature contours for a model gas turbine combustor

    CSIR Research Space (South Africa)

    Meyers, BC

    2011-09-01

    Full Text Available A three-component flow field inside a can-type, forward flow experimental combustor was measured under non-reacting conditions. The combustor was run at atmospheric conditions with the air flow supplied from a fan and the outlet was straight...

  19. Single photon simultaneous K-shell ionization and K-shell excitation. I. Theoretical model applied to the interpretation of experimental results on H2O

    International Nuclear Information System (INIS)

    Carniato, S.; Selles, P.; Andric, L.; Palaudoux, J.; Penent, F.; Lablanquie, P.; Žitnik, M.; Bučar, K.; Nakano, M.; Hikosaka, Y.; Ito, K.

    2015-01-01

    We present in detail a theoretical model that provides absolute cross sections for simultaneous core-ionization core-excitation (K −2 V ) and compare its predictions with experimental results obtained on the water molecule after photoionization by synchrotron radiation. Two resonances of different symmetries are assigned in the main K −2 V peak and comparable contributions from monopolar (direct shake-up) and dipolar (conjugate shake-up) core-valence excitations are identified. The main peak is observed with a much greater width than the total experimental resolution. This broadening is the signature of nuclear dynamics

  20. Computations for a condenser. Experimental results

    International Nuclear Information System (INIS)

    Walden, Jean.

    1975-01-01

    Computations for condensers are presented with experimental results. The computations are concerned with the steam flux at the condenser input, and inside the tube bundle. Experimental results are given for the flux inside the condenser sleeve and the flow passing through the tube bundle [fr

  1. Comparison of Experimentally Measured Deformation of the Plate on the Subsoil and the Results of 3D Numerical Model

    Directory of Open Access Journals (Sweden)

    Labudková Jana

    2014-06-01

    Full Text Available The purpose of this paper is to compare the measured subsidence of the foundation in experiments and subsidence obtained from FEM calculations. When using 3D elements for creation of a 3D model, it is, in particular, essential to choose correctly the size of the modelled area which represents the subsoil, the boundary conditions and the size of the finite element network. The parametric study evaluates impacts of those parameters on final deformation. The parametric study is conducted of 168 variant models.

  2. Artificial neural network simulations and experimental results ...

    African Journals Online (AJOL)

    It was established that the experimental data fit the selected adsorption isotherms in the following order: Langmuir > Freundlich > Temkin > Dubinin-Radushkevich (D-R). Kinetic modelling was done using intra-particle diffusion, liquid-film, pseudo-first order and pseudo-second order models. With the aid of the normalised ...

  3. Detailed experimental results for laser acceleration staging

    Directory of Open Access Journals (Sweden)

    W. D. Kimura

    2001-10-01

    Full Text Available Detailed experimental results of staging two laser-driven, relativistic electron accelerators are presented. During the experiment called STELLA (staged electron laser acceleration, an inverse free-electron laser (IFEL is used to modulate the electron energy, thereby, causing ∼3 fs microbunches to form separated by the laser wavelength at 10.6 μm (equivalent to a 35 fs period. A second IFEL accelerates the electrons depending upon the phase of the microbunches entering the second IFEL with respect to the laser beam driving the second IFEL. The data presented includes electron energy spectra as a function of the phase delay and laser power driving the first IFEL. Also shown is a comparison with the computer model, which includes space charge and misalignment effects.

  4. Modeling of the Ionic Multi-Species Transport Phenomena in Electrokinetic Processes and Comparison with Experimental Results

    DEFF Research Database (Denmark)

    Paz-Garcia, Juan Manuel; Johannesson, Björn; Ottosen, Lisbeth M.

    2010-01-01

    . Electrical neutrality was continuously assured in the model by the inclusion of the Poisson-Boltzmann equation to the system of governing equations. Voltage differences were applied across the sample as boundary conditions in order to evaluate the competition between diffusion and electromigration terms......A model to predict the transport of ionic species within the pore solution of porous materials, under the effect of an external electric field has been developed. A Finite Elements method was implemented and used for the integration of the Nernst-Plank equations for each ionic species considered...

  5. On-line monitoring and modelling based process control of high rate nitrification - lab scale experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Pirsing, A. [Technische Univ. Berlin (Germany). Inst. fuer Verfahrenstechnik; Wiesmann, U. [Technische Univ. Berlin (Germany). Inst. fuer Verfahrenstechnik; Kelterbach, G. [Technische Univ. Berlin (Germany). Inst. fuer Mess- und Regelungstechnik; Schaffranietz, U. [Technische Univ. Berlin (Germany). Inst. fuer Mess- und Regelungstechnik; Roeck, H. [Technische Univ. Berlin (Germany). Inst. fuer Mess- und Regelungstechnik; Eichner, B. [Technische Univ. Berlin (Germany). Inst. fuer Anorganische und Analytische Chemie; Szukal, S. [Technische Univ. Berlin (Germany). Inst. fuer Anorganische und Analytische Chemie; Schulze, G. [Technische Univ. Berlin (Germany). Inst. fuer Anorganische und Analytische Chemie

    1996-09-01

    This paper presents a new concept for the control of nitrification in highly polluted waste waters. The approach is based on mathematical modelling. To determine the substrate degradation rates of the microorganisms involved, a mathematical model using gas measurement is used. A fuzzy-controller maximises the capacity utilisation efficiencies. The experiments carried out in a lab-scale reactor demonstrate that even with highly varying ammonia concentrations in the influent, the nitrogen concentrations in the effluent can be kept within legal limits. (orig.). With 11 figs.

  6. Comparison of five in vitro digestion models to in vivo experimental results: Lead bioaccessibility in the human gastrointestinal tract

    NARCIS (Netherlands)

    Wiele, T.R. van de; Oomen, A.G.; Wragg, J.; Cave, M.; Minekus, M.; Hack, A.; Cornelis, C.; Rompelberg, C.J.M.; Zwart, L.L. de; Klinck, B.; Wijnen, J. van; Verstraete, W.; Sips, A.J.A.M.

    2007-01-01

    This paper presents a multi-laboratory comparison study of in vitro models assessing bioaccessibility of soil-bound lead in the human gastrointestinal tract under simulated fasted and fed conditions. Oral bioavailability data from a previous human in vivo study on the same soil served as a reference

  7. Experimental result analysis for scaled model of UiTM tailless blended wing-body (BWB) Baseline 7 unmanned aerial vehicle (UAV)

    Science.gov (United States)

    Nasir, R. E. M.; Ahmad, A. M.; Latif, Z. A. A.; Saad, R. M.; Kuntjoro, W.

    2017-12-01

    Blended wing-body (BWB) aircraft having planform configuration similar to those previously researched and published by other researchers does not guarantee that an efficient aerodynamics in term of lift-to-drag ratio can be achieved. In this wind tunnel experimental study, BWB half model is used. The model is also being scaled down to 71.5% from the actual size. Based on the results, the maximum lift coefficient is found to be 0.763 when the angle is at 27.5° after which the model starts to stall. The minimum drag coefficient is 0.014, measured at zero angle of attack. The corrected lift-to-drag ratio (L/D) is 15.9 at angle 7.8°. The scaled model has a big flat surface that surely gives an inaccurate data but the data obtained shall give some insights for future perspective towards the BWB model being tested.

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  9. PEMFC modeling and experimental validation

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, J.V.C. [Federal University of Parana (UFPR), Curitiba, PR (Brazil). Dept. of Mechanical Engineering], E-mail: jvargas@demec.ufpr.br; Ordonez, J.C.; Martins, L.S. [Florida State University, Tallahassee, FL (United States). Center for Advanced Power Systems], Emails: ordonez@caps.fsu.edu, martins@caps.fsu.edu

    2009-07-01

    In this paper, a simplified and comprehensive PEMFC mathematical model introduced in previous studies is experimentally validated. Numerical results are obtained for an existing set of commercial unit PEM fuel cells. The model accounts for pressure drops in the gas channels, and for temperature gradients with respect to space in the flow direction, that are investigated by direct infrared imaging, showing that even at low current operation such gradients are present in fuel cell operation, and therefore should be considered by a PEMFC model, since large coolant flow rates are limited due to induced high pressure drops in the cooling channels. The computed polarization and power curves are directly compared to the experimentally measured ones with good qualitative and quantitative agreement. The combination of accuracy and low computational time allow for the future utilization of the model as a reliable tool for PEMFC simulation, control, design and optimization purposes. (author)

  10. The commissioning of the advanced radiographic capability laser system: experimental and modeling results at the main laser output

    Science.gov (United States)

    Di Nicola, J. M.; Yang, S. T.; Boley, C. D.; Crane, J. K.; Heebner, J. E.; Spinka, T. M.; Arnold, P.; Barty, C. P. J.; Bowers, M. W.; Budge, T. S.; Christensen, K.; Dawson, J. W.; Erbert, G.; Feigenbaum, E.; Guss, G.; Haefner, C.; Hermann, M. R.; Homoelle, D.; Jarboe, J. A.; Lawson, J. K.; Lowe-Webb, R.; McCandless, K.; McHale, B.; Pelz, L. J.; Pham, P. P.; Prantil, M. A.; Rehak, M. L.; Rever, M. A.; Rushford, M. C.; Sacks, R. A.; Shaw, M.; Smauley, D.; Smith, L. K.; Speck, R.; Tietbohl, G.; Wegner, P. J.; Widmayer, C.

    2015-02-01

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is the first of a kind megajoule-class laser with 192 beams capable of delivering over 1.8 MJ and 500TW of 351nm light [1], [2]. It has been commissioned and operated since 2009 to support a wide range of missions including the study of inertial confinement fusion, high energy density physics, material science, and laboratory astrophysics. In order to advance our understanding, and enable short-pulse multi-frame radiographic experiments of dense cores of cold material, the generation of very hard x-rays above 50 keV is necessary. X-rays with such characteristics can be efficiently generated with high intensity laser pulses above 1017 W/cm² [3]. The Advanced Radiographic Capability (ARC) [4] which is currently being commissioned on the NIF will provide eight, 1 ps to 50 ps, adjustable pulses with up to 1.7 kJ each to create x-ray point sources enabling dynamic, multi-frame x-ray backlighting. This paper will provide an overview of the ARC system and report on the laser performance tests conducted with a stretched-pulse up to the main laser output and their comparison with the results of our laser propagation codes.

  11. Groundwater-derived nutrient and trace element transport to a nearshore Kona coral ecosystem: Experimental mixing model results

    Directory of Open Access Journals (Sweden)

    Nancy G. Prouty

    2017-06-01

    New Hydrological Insights for the Region: Treated wastewater effluent was the main source for nutrient enrichment downstream at the Honokōhau Harbor site. Conservative mixing for some constituents, such as nitrate + nitrite, illustrate the effectiveness of physical mixing to maintain oceanic concentrations in the colloid (0.02–0.45 μm and truly dissolved (<0.02 μm forms. In contrast, the nonconservative behavior of phosphate highlights the importance of surface complexation reactions that can lead to higher concentrations based on conservative mixing alone. Results from this physiochemical mixing experiment demonstrate how relative availability of P can shift with adsorption behavior, affecting the mobility of phosphate in the environment. With a proposed 8-hectare wastewater treatment facility (WWTF to be constructed upslope of the Kaloko-Honokōhau National Historical Park (NHP, treated effluent is projected to add additional nutrients. Combined with high permeability, rapid discharge, and increased nutrient loading SGD will likely continue to serve as a persistent source of nutrients and potential contaminant to coral ecosystems.

  12. Micro-scale finite element modeling of ultrasound propagation in aluminum trabecular bone-mimicking phantoms: A comparison between numerical simulation and experimental results.

    Science.gov (United States)

    Vafaeian, B; Le, L H; Tran, T N H T; El-Rich, M; El-Bialy, T; Adeeb, S

    2016-05-01

    The present study investigated the accuracy of micro-scale finite element modeling for simulating broadband ultrasound propagation in water-saturated trabecular bone-mimicking phantoms. To this end, five commercially manufactured aluminum foam samples as trabecular bone-mimicking phantoms were utilized for ultrasonic immersion through-transmission experiments. Based on micro-computed tomography images of the same physical samples, three-dimensional high-resolution computational samples were generated to be implemented in the micro-scale finite element models. The finite element models employed the standard Galerkin finite element method (FEM) in time domain to simulate the ultrasonic experiments. The numerical simulations did not include energy dissipative mechanisms of ultrasonic attenuation; however, they expectedly simulated reflection, refraction, scattering, and wave mode conversion. The accuracy of the finite element simulations were evaluated by comparing the simulated ultrasonic attenuation and velocity with the experimental data. The maximum and the average relative errors between the experimental and simulated attenuation coefficients in the frequency range of 0.6-1.4 MHz were 17% and 6% respectively. Moreover, the simulations closely predicted the time-of-flight based velocities and the phase velocities of ultrasound with maximum relative errors of 20 m/s and 11 m/s respectively. The results of this study strongly suggest that micro-scale finite element modeling can effectively simulate broadband ultrasound propagation in water-saturated trabecular bone-mimicking structures. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. A regenerative elastocaloric device: Experimental results

    DEFF Research Database (Denmark)

    Engelbrecht, Kurt; Tusek, Jaka; Eriksen, Dan

    2017-01-01

    Elastocaloric cooling and heating is an alternative cooling technology that has potential to be highly efficient and environmentally friendly. Experimental results are reported for two elastocaloric regenerators made of NiTi alloys in the form of parallel plates in two plate thicknesses. For the ......Elastocaloric cooling and heating is an alternative cooling technology that has potential to be highly efficient and environmentally friendly. Experimental results are reported for two elastocaloric regenerators made of NiTi alloys in the form of parallel plates in two plate thicknesses...

  14. CONDUCTING AND ANALYZING THE RESULTS OF THE EXPERIMENTAL BOX TEST OF RETAINING WALL MODELS WITHOUT PILES AND ON THE PILE FOUNDATION

    Directory of Open Access Journals (Sweden)

    M. A. Lisnevskyi

    2015-08-01

    Full Text Available Purpose. Taking into consideration that the bearing capacity of the foundation may be insufficient, in the study it is assumed that pile foundation can be used to reduce the impact of the construction of new retaining structures on roads and railways near the existing buildings or in areas of dense urban development and ensure the stability of the foundation. To reduce the volume of excavation it is necessary to choose the economic structure of the retaining wall. To do this, one should explore stress-strain state (SSS of the retaining walls, to develop methods to improve their strength and stability, as well as to choose the most appropriate method of their analysis. Methodology. In the design of retaining walls foundation mat and piles are considered as independent elements. Since the combined effect of the retaining wall, piles and foundation mat as well as the effect of soil or rock foundation on the structure are considered not fully, so there are some limitations in the existing design techniques. To achieve the purpose the box tests of retaining walls models without piles and with piles for studying their interaction with the surrounding soil massif were conducted. Findings. Laboratory simulation of complex systems «surrounding soil – retaining wall – pile» was carried out and on the basis of the box test results were analyzed strains and its main parameters of the stress-strain state. Analysis of the results showed that the structure of a retaining wall with piles is steady and stable. Originality. So far, in Ukraine has not been carried out similar experimental box tests with models of retaining walls in such combinations. In the article has been presented unique photos and test results, as well as their analysis. Practical value. Using the methodology of experimental tests of the retaining wall models with piles and without them gives a wider opportunity to study stress-strain state of such structures.

  15. Comparison and validation of HEU and LEU modeling results to HEU experimental benchmark data for the Massachusetts Institute of Technology MITR reactor.

    Energy Technology Data Exchange (ETDEWEB)

    Newton, T. H.; Wilson, E. H; Bergeron, A.; Horelik, N.; Stevens, J. (Nuclear Engineering Division); (MIT Nuclear Reactor Lab.)

    2011-03-02

    The Massachusetts Institute of Technology Reactor (MITR-II) is a research reactor in Cambridge, Massachusetts designed primarily for experiments using neutron beam and in-core irradiation facilities. It delivers a neutron flux comparable to current LWR power reactors in a compact 6 MW core using Highly Enriched Uranium (HEU) fuel. In the framework of its non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used for nuclear weapons. In this geopolitical context, most research and test reactors both domestic and international have started a program of conversion to the use of Low Enriched Uranium (LEU) fuel. A new type of LEU fuel based on an alloy of uranium and molybdenum (UMo) is expected to allow the conversion of U.S. domestic high performance reactors like the MITR-II reactor. Towards this goal, comparisons of MCNP5 Monte Carlo neutronic modeling results for HEU and LEU cores have been performed. Validation of the model has been based upon comparison to HEU experimental benchmark data for the MITR-II. The objective of this work was to demonstrate a model which could represent the experimental HEU data, and therefore could provide a basis to demonstrate LEU core performance. This report presents an overview of MITR-II model geometry and material definitions which have been verified, and updated as required during the course of validation to represent the specifications of the MITR-II reactor. Results of calculations are presented for comparisons to historical HEU start-up data from 1975-1976, and to other experimental benchmark data available for the MITR-II Reactor through 2009. This report also presents results of steady state neutronic analysis of an all-fresh LEU fueled core. Where possible, HEU and LEU calculations were performed for conditions equivalent to HEU experiments, which serves as a starting point for safety analyses for conversion of MITR-II from the use of HEU

  16. Experimental Object-Oriented Modelling

    DEFF Research Database (Denmark)

    Hansen, Klaus Marius

    and discuss techniques for handling and representing uncertainty when modelling in experimental system development. These techniques are centred on patterns and styles for handling uncertainty in object-oriented software architectures. Tools We present the Knight tool designed for collaborative modelling...... in experimental system development and discuss its design, implementation, and evaluation. The tool has subsequently been successfully commercialized. In summary, this thesis presents techniques and tools that advance the effectiveness and efficiency of experimental modelling.......This thesis examines object-oriented modelling in experimental system development. Object-oriented modelling aims at representing concepts and phenomena of a problem domain in terms of classes and objects. Experimental system development seeks active experimentation in a system development project...

  17. Experimental results from the small isochronous ring

    Energy Technology Data Exchange (ETDEWEB)

    Eduard Pozdeyev

    2005-05-01

    The Small Isochronous Ring (SIR) is a compact, low-energy storage ring designed to investigate the beam dynamics of high-intensity isochronous cyclotrons and synchrotrons at the transition energy. The ring was developed at Michigan State University (MSU) and has been operational since December 2003. It stores 20 keV hydrogen beams with a peak current of 10-20 microamps for up to 200 turns. The transverse and longitudinal profiles of extracted bunches are measured with an accuracy of approximately 1 mm. The high accuracy of the measurements makes the experimental data attractive for validation of multi-particle space charge codes. The results obtained in the ring show a fast growth of the energy spread induced by the space charge forces. The energy spread growth is accompanied by a breakup of the beam bunches into separated clusters that are involved in the vortex motion specific to the isochronous regime. The experimental results presented in the paper show a remarkable agreement with simulations performed with the code CYCO. In this paper, we discuss specifics of space charge effects in the isochronous regime, present results of experiments in SIR, and conduct a detailed comparison of the experimental data with results of simulations.

  18. 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

  19. CEC thermal-hydraulic benchmark exercise on Fiploc verification experiment F2 in Battelle model containment. Experimental phases 2, 3 and 4. Results of comparisons

    International Nuclear Information System (INIS)

    Fischer, K.; Schall, M.; Wolf, L.

    1993-01-01

    The present final report comprises the major results of Phase II of the CEC thermal-hydraulic benchmark exercise on Fiploc verification experiment F2 in the Battelle model containment, experimental phases 2, 3 and 4, which was organized and sponsored by the Commission of the European Communities for the purpose of furthering the understanding and analysis of long-term thermal-hydraulic phenomena inside containments during and after severe core accidents. This benchmark exercise received high European attention with eight organizations from six countries participating with eight computer codes during phase 2. Altogether 18 results from computer code runs were supplied by the participants and constitute the basis for comparisons with the experimental data contained in this publication. This reflects both the high technical interest in, as well as the complexity of, this CEC exercise. Major comparison results between computations and data are reported on all important quantities relevant for containment analyses during long-term transients. These comparisons comprise pressure, steam and air content, velocities and their directions, heat transfer coefficients and saturation ratios. Agreements and disagreements are discussed for each participating code/institution, conclusions drawn and recommendations provided. The phase 2 CEC benchmark exercise provided an up-to-date state-of-the-art status review of the thermal-hydraulic capabilities of present computer codes for containment analyses. This exercise has shown that all of the participating codes can simulate the important global features of the experiment correctly, like: temperature stratification, pressure and leakage, heat transfer to structures, relative humidity, collection of sump water. Several weaknesses of individual codes were identified, and this may help to promote their development. As a general conclusion it may be said that while there is still a wide area of necessary extensions and improvements, the

  20. Role of soil-to-leaf tritium transfer in controlling leaf tritium dynamics: Comparison of experimental garden and tritium-transfer model results.

    Science.gov (United States)

    Ota, Masakazu; Kwamena, Nana-Owusua A; Mihok, Steve; Korolevych, Volodymyr

    2017-11-01

    Environmental transfer models assume that organically-bound tritium (OBT) is formed directly from tissue-free water tritium (TFWT) in environmental compartments. Nevertheless, studies in the literature have shown that measured OBT/HTO ratios in environmental samples are variable and generally higher than expected. The importance of soil-to-leaf HTO transfer pathway in controlling the leaf tritium dynamics is not well understood. A model inter-comparison of two tritium transfer models (CTEM-CLASS-TT and SOLVEG-II) was carried out with measured environmental samples from an experimental garden plot set up next to a tritium-processing facility. The garden plot received one of three different irrigation treatments - no external irrigation, irrigation with low tritium water and irrigation with high tritium water. The contrast between the results obtained with the different irrigation treatments provided insights into the impact of soil-to-leaf HTO transfer on the leaf tritium dynamics. Concentrations of TFWT and OBT in the garden plots that were not irrigated or irrigated with low tritium water were variable, responding to the arrival of the HTO-plume from the tritium-processing facility. In contrast, for the plants irrigated with high tritium water, the TFWT concentration remained elevated during the entire experimental period due to a continuous source of high HTO in the soil. Calculated concentrations of OBT in the leaves showed an initial increase followed by quasi-equilibration with the TFWT concentration. In this quasi-equilibrium state, concentrations of OBT remained elevated and unchanged despite the arrivals of the plume. These results from the model inter-comparison demonstrate that soil-to-leaf HTO transfer significantly affects tritium dynamics in leaves and thereby OBT/HTO ratio in the leaf regardless of the atmospheric HTO concentration, only if there is elevated HTO concentrations in the soil. The results of this work indicate that assessment models

  1. 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 + 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.

  2. 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.

  3. Fly's proprioception-inspired micromachined strain-sensing structure: idea, design, modeling and simulation, and comparison with experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Wicaksono, D H B [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Zhang, L-J [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Pandraud, G [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); French, P J [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Vincent, J F V [Department of Mech. Engineering, Bath University Bath, BA2 7AY (United Kingdom)

    2006-04-01

    A new strain-sensing structure inspired from insect's (especially the Fly) propricoception sensor is devised. The campaniform sensillum is a strain-sensing microstructure with very high sensitivity despite its small dimension (diameter {approx}10 {mu}m in a relatively stiff material of insect's exocuticle (E = {approx}10{sup 9} Pa). Previous work shows that the high sensitivity of this structure towards strain is due to its membrane-in-recess- and strainconcentrating-hole-features. Based on this inspiration, we built similar structure using silicon micromachining technology. Then a simple characterisation setup was devised. Here, we present briefly, finite-element modeling and simulation based on this actual sample preparation for the characterisation. As comparison and also to understand mechanical features responsible for the strain-sensitivity, we performed the modeling on different mechanical structures: bulk chunk, blind-hole, through-hole, surface membrane, and membrane-in-recess. The actual experimental characterisation was performed previously using optical technique to membrane in-recess micromachined Si structure. The FEM simulation results confirm that the bending stress and strain are concentrated in the hole-vicinity. The membrane inside the hole acts as displacement transducer. The FEM is in conformity with previous analytical results, as well as the optical characterisation result. The end goal is to build a new type MEMS strain sensor.

  4. Atmospheric Deposition Modeling Results

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset provides data on model results for dry and total deposition of sulfur, nitrogen and base cation species. Components include deposition velocities, dry...

  5. Fuel-rich, catalytic reaction experimental results

    Science.gov (United States)

    Rollbuhler, R. James

    1991-01-01

    Future aeropropulsion gas turbine combustion requirements call for operating at very high inlet temperatures, pressures, and large temperature rises. At the same time, the combustion process is to have minimum pollution effects on the environment. Aircraft gas turbine engines utilize liquid hydrocarbon fuels which are difficult to uniformly atomize and mix with combustion air. An approach for minimizing fuel related problems is to transform the liquid fuel into gaseous form prior to the completion of the combustion process. Experimentally obtained results are presented for vaporizing and partially oxidizing a liquid hydrocarbon fuel into burnable gaseous components. The presented experimental data show that 1200 to 1300 K reaction product gas, rich in hydrogen, carbon monoxide, and light-end hydrocarbons, is formed when flowing 0.3 to 0.6 fuel to air mixes through a catalyst reactor. The reaction temperatures are kept low enough that nitrogen oxides and carbon particles (soot) do not form. Results are reported for tests using different catalyst types and configurations, mass flowrates, input temperatures, and fuel to air ratios.

  6. 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.

  7. Results of the AVATAR project for the validation of 2D aerodynamic models with experimental data of the DU95W180 airfoil with unsteady flap

    DEFF Research Database (Denmark)

    Ferreira, C.; Gonzalez, A.; Baldacchino, D.

    2016-01-01

    is the application of flow control devices, such as flaps. In Task 3.2: Development of aerodynamic codes for modelling of flow devices on aerofoils and, rotors of the Avatar project, aerodynamic codes are benchmarked and validated against the experimental data of a DU95W180 airfoil in steady and unsteady flow......, for different angle of attack and flap settings, including unsteady oscillatory trailing-edge-flap motion, carried out within the framework of WP3: Models for Flow Devices and Flow Control, Task 3.1: CFD and Experimental Database. The aerodynamics codes are: AdaptFoil2D, Foil2W, FLOWer, MaPFlow, OpenFOAM, Q3UIC......, ATEFlap. The codes include unsteady Eulerian CFD simulations with grid deformation, panel models and indicial engineering models. The validation cases correspond to 18 steady flow cases, and 42 unsteady flow cases, for varying angle of attack, flap deflection and reduced frequency, with free and forced...

  8. 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.

  9. 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.

  10. Comparison with Experimental Results of Models and Modelling with Fuzzy Logic of the Effect on Surface Roughness of Cutting Parameters in Machining of Co28Cr6Mowrought Steels

    Science.gov (United States)

    Asilturk, Ilhan; AlperInce, Mehmet

    2017-06-01

    This study includes comparison with experimental results of models and modelling with fuzzy logic of the effect on surface roughness of cutting parameters (rotational speed (n), feed rate (f), depth of cut (a) and tool tip radius (r)) in CNC turning of Co28Cr6Mo wrought steels. Fuzzy logic modelswere established that can determine the optimum rotational speed, feed rate, depth of cut and tool tip radius for surface roughness (Ra) according to the hardness of material and type of cutting tool. In the model created using fuzzy logic, membership functions and foot widths of input parameters and output parameter were utilized. In the rule base, triangular (trim-f) membership functions were selected by the Mamdani approach. The results obtained using this fuzzymodel and experimental results were interpreted and compared with 2dimensional graphics.

  11. Progressive distortion. Use of experimental results

    International Nuclear Information System (INIS)

    Thomas, Pierre.

    1980-04-01

    In order to evaluate the risk of failure due to excessive distortion, concerning structures which are submitted to both primary stress P and secondary cyclic stress ΔQ, one can use some diagrams which give ranges of stress where the rachetting appears or not. A recent rachetting curve, in which one defines an effective primary stress Peff (which includes effects different from those of secondary stress ΔQ) is very general. That diagram, coming from experiments, appears to be conservative enough in order to define the risk of rachetting, and deserves being more validated. In that paper, we applied to that diagram the results of three bars test performed by Takeo Uga. In that very simple case, the secondary stress is a thermal stress, and the instantaneous characteristics of steel are the only requested. One can verify that after spotting experimental points on the diagram, all are well placed [fr

  12. A regenerative elastocaloric device: experimental results

    International Nuclear Information System (INIS)

    Engelbrecht, Kurt; Eriksen, Dan; Lei, Tian; Lee, Chong-Yi; Pryds, Nini; Tušek, Jaka; Tušek, Janez

    2017-01-01

    Elastocaloric cooling and heating is an alternative cooling technology that has the potential to be highly efficient and environmentally friendly. Experimental results are reported for two elastocaloric regenerators made of Ni–Ti alloys in the form of parallel plates in two plate thicknesses. For the regenerator made of 0.2 mm plates, a maximum no-load temperature span of 17.6 K was achieved for an applied strain of 4.3%. For the regenerator with 0.35 mm plates, a maximum temperature span of 19.9 K was reached for a strain of 3.5%. The 0.2 mm regenerator failed after approximately 5200 cycles and the 0.35 mm regenerator failed after approximately 5500 cycles. (paper)

  13. Experimental and modeling results on geochemical impacts of leaking CO2 from subsurface storage reservoirs to an unconfined oxidizing carbonate aquifer

    Science.gov (United States)

    Qafoku, N. P.; Bacon, D. H.; Shao, H.; Lawter, A.; Wang, G.; Brown, C. F.

    2013-12-01

    Deep subsurface storage and sequestration of CO2 has been identified as a potential mitigation technique for rising atmospheric CO2 concentrations. Sequestered CO2 represents a potential risk to overlying aquifers if the CO2 leaks from the deep storage reservoir. Experimental and modeling work is required to evaluate risks to groundwater quality and develop a systematic understanding on how CO2 leakage may cause important changes in aquifer chemistry and mineralogy by promoting dissolution/precipitation, adsorption/desorption, and redox reactions. Solid materials (rocks and slightly weathered rocks) from an unconfined aquifer, i.e., the Edwards Aquifer in Texas, were used in this investigation. The experimental part consisted of: 1) wet chemical acid extractions (8M HNO3 solution at 90 0C); 2) batch experiments conducted at low solid to solution ratios to study time-dependent releases of major, minor and trace elements during periodic or continuous exposure to CO2 gas; 3) hydraulically saturated column experiments conducted under continuous and stop-flow conditions using a CO2 gas saturated synthetic groundwater; 4) pre- and post-treatment solid phase characterization studies. Major variables tested included reaction time (0-336 hours), CO2 flow rate (50 to 350 ml/min), brine concentration (0.1 and 1 M NaCl), rock type and particle size fraction. We are currently investigating the solution composition effects (i.e., presence of contaminants in the initial solution) on the fate and behavior of potential contaminants (As, Pb and Cd) in these systems. Results from the solid phase characterization studies showed that the mineralogy of the Edwards aquifer materials was dominated by calcite. Quartz and montmorillonite were also present in some samples. Acid extractions confirmed that the solid phase had appreciable amounts of potential contaminants (As, Cd, Cr, Cu, Pb and Zn). However, the results from the batch and column experiments demonstrated that these contaminants

  14. Mechanism of Reaction in NaAlCl4 Molten Salt Batteries with Nickel Felt Cathodes and Aluminum Anodes. Part II: Experimental Results and Comparison with Model Calculations

    DEFF Research Database (Denmark)

    Knutz, B.C.; Berg, Rolf W.; Hjuler, Hans Aage

    1993-01-01

    The battery systems: Al/NaCl-AlCl3-Al(2)X(3)/Ni-felt (X = S, Se, Te) and the corresponding system without chalcogen have been studied experimentally at 175 degrees C. Charge/discharge experimental performed on cells with NaCl saturated melts, show that advantages with regard to rate capability an...... by coulometric titrations (performed on cells with slightly acidic NaCl-AlCl3 melts and small amounts of chalcogen) and compared with model calculations. Cells containing chalcogen revealed at least three voltage plateaus during cycling. The lowest plateau is associated with formation...

  15. Calculation of the Intensity of Physical Time Fluctuations Using the Standard Solar Model and its Comparison with the Results of Experimental Measurements

    Science.gov (United States)

    Morozov, A. N.

    2017-11-01

    The article reviews the possibility of describing physical time as a random Poisson process. An equation allowing the intensity of physical time fluctuations to be calculated depending on the entropy production density within irreversible natural processes has been proposed. Based on the standard solar model the work calculates the entropy production density inside the Sun and the dependence of the intensity of physical time fluctuations on the distance to the centre of the Sun. A free model parameter has been established, and the method of its evaluation has been suggested. The calculations of the entropy production density inside the Sun showed that it differs by 2-3 orders of magnitude in different parts of the Sun. The intensity of physical time fluctuations on the Earth's surface depending on the entropy production density during the sunlight-to-Earth's thermal radiation conversion has been theoretically predicted. A method of evaluation of the Kullback's measure of voltage fluctuations in small amounts of electrolyte has been proposed. Using a simple model of the Earth's surface heat transfer to the upper atmosphere, the effective Earth's thermal radiation temperature has been determined. A comparison between the theoretical values of the Kullback's measure derived from the fluctuating physical time model and the experimentally measured values of this measure for two independent electrolytic cells showed a good qualitative and quantitative concurrence of predictions of both theoretical model and experimental data.

  16. The effect of a combination of gabapentin and donepezil in an experimental pain model in healthy volunteers: Results of a randomized controlled trial.

    Science.gov (United States)

    Boyle, Yvonne; Fernando, Disala; Kurz, Hazel; Miller, Sam R; Zucchetto, Mauro; Storey, James

    2014-12-01

    This double-blind, placebo-controlled, 3-period cross-over, 4-treatment option, incomplete block study (ClinicalTrials.gov number NCT01485185), with an adaptive design for sample size re-estimation, was designed to evaluate gabapentin plus donepezil in an established experimental model of electrical hyperalgesia. Thirty healthy male subjects aged 18-55 years were randomized to receive gabapentin 900 mg or gabapentin 900 mg+donepezil 5mg for 2 of the 3 treatment periods, with 50% of subjects randomized to receive placebo (negative control) and 50% to gabapentin 1800 mg (positive control) for the remaining period. Each treatment period was 14 days. Gabapentin or corresponding placebo was administered on Day 13 and the morning of Day 14. Donepezil or corresponding placebo was administered nocturnally from Day 1-13 and the morning of Day 14. Co-primary endpoints were the area of pinprick hyperalgesia (260 mN von Frey filament) and allodynia (stroking by cotton bud) evoked by electrical hyperalgesia on Day 14. Gabapentin 1800 mg (n=14) significantly reduced the area of allodynia vs placebo (n=14; -12.83 cm(2); 95% confidence interval [CI] -23.14 to -2.53; P=0.015) with supportive results for hyperalgesia (-14.04 cm(2); 95% CI -28.49-0.41; P=0.057), validating the electrical hyperalgesia model. Gabapentin+donepezil (n=30) significantly reduced the area of hyperalgesia vs gabapentin 900 mg (n=30; -11.73 cm(2); 95% CI -21.04 to -2.42; P=0.014), with supportive results for allodynia (-6.62 cm(2); 95% CI -13.29-0.04; P=0.052). The adverse event profile for gabapentin+donepezil was similar to the same dose of gabapentin. Data are supportive of further clinical investigation of a gabapentin-and-donepezil combination in patients with an inadequate response to gabapentin. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  17. Comparison of the Experimental and Numerical Results of Modelling a 32-Oscillating Water Column (OWC, V-Shaped Floating Wave Energy Converter

    Directory of Open Access Journals (Sweden)

    John V. Ringwood

    2013-08-01

    Full Text Available Combining offshore wind and wave energy converting apparatuses presents a number of potentially advantageous synergies. To facilitate the development of a proposed floating platform combining these two technologies, proof of concept scale model testing on the wave energy converting component of this platform has been conducted. The wave energy component is based on the well-established concept of the oscillating water column. A numerical model of this component has been developed in the frequency domain, and the work presented here concerns the results of this modelling and testing. The results of both are compared to assess the validity and usefulness of the numerical model.

  18. 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.)

  19. Early changes in experimental osteoarthritis using the Pond-Nuki dog model: technical procedure and initial results of in vivo MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Libicher, Martin [University of Heidelberg, Department of Radiology, Heidelberg (Germany); Ivancic, Mate; Hoffmann, Volker; Wenz, Wolfram [University of Heidelberg, Department of Orthopaedics, Heidelberg (Germany)

    2005-02-01

    The purpose of this study was to prove the feasibility of combining in vivo MR imaging with the Pond-Nuki animal model for the evaluation of osteoarthritis. In an experimental study, 24 beagle dogs underwent transection of the anterior cruciate ligament of the left leg (modified Pond-Nuki model). The dogs were randomly assigned into four groups and examined by MRI after 6, 12, 24 and 48 weeks. MR imaging of both knees was performed under general anesthesia with the contralateral joint serving as control. In group 1 (6 weeks postoperatively), the first sign detected on MRI was subchondral bone marrow edema in the posteromedial tibia. After 12 weeks, erosion of the posteromedial tibial cartilage could be observed, followed by meniscus degeneration and osteophytosis after 24 and 48 weeks. The contralateral knee joint showed transient joint effusion, but no significant signs of internal derangement (P<0.001). By combining in vivo MR imaging with the Pond-Nuki model, it is possible to detect early signs of osteoarthritis. The first sign was posteromedial subchondral bone marrow edema in the tibia followed by progressive cartilage degeneration and joint derangement. The in vivo model therefore seems to be suitable for longitudinal studies or monitoring the therapeutic effects of osteoarthritis. (orig.)

  20. Understanding Leadership: An Experimental-Experiential Model

    Science.gov (United States)

    Hole, George T.

    2014-01-01

    Books about leadership are dangerous to readers who fantasize about being leaders or apply leadership ideas as if they were proven formulas. As an antidote, I offer an experimental framework in which any leadership-management model can be tested to gain experiential understanding of the model. As a result one can gain reality-based insights about…

  1. Experimental results on SUSY searches with top

    CERN Document Server

    Eifert, Till

    2014-01-01

    Searches for supersymmetric partner particles of the top and bottom quarks at the Large Hadron Collider are reviewed. The focus is on the status of searches for a relatively light partner of the top quark performed by the CMS and ATLAS Collaborations. No excess beyond Standard Model expectations is observed and exclusion limits are set on the masses of supersymmetric particles.

  2. Experimental results in muon-catalyzed fusion

    International Nuclear Information System (INIS)

    Jones, S.E.

    1990-01-01

    Overall, it may be possible to look back over the past decade of research and conclude that muon-catalyzed fusion yields have significantly exceeded expectations, leading to renewed speculation regarding applications. Concerning the muon catalysis cycling rate, it is concluded that reaction rates and the overall catalysis cycling rate deserve further exploration, and that the rates are sufficiently fast to permit many hundreds of fusions during the muon lifetime. Various ways in which muons may be lost from the catalysis cycle are then described and discussed, and good agreement is obtained between experimental alpha-muon sticking values at liquid density. These values lie below the theoretical expectation, an outstanding mystery in muon-catalyzed cold fusion. Considerable progress has been made in understanding the alpha-muon sticking probability and related mechanisms. It is also clear that sticking is the major bottleneck in the muon catalysis cycle. In connection with expected fusion yields, to produce power commercially using μcf alone would probably require an order-of-magnitude increase in the yield per muon, assuming advanced technology for muon production. (N.K.)

  3. Experimental Modeling of Dynamic Systems

    DEFF Research Database (Denmark)

    Knudsen, Morten Haack

    2006-01-01

    An engineering course, Simulation and Experimental Modeling, has been developed that is based on a method for direct estimation of physical parameters in dynamic systems. Compared with classical system identification, the method appears to be easier to understand, apply, and combine with physical...... insight. It is based on a sensitivity approach that is useful for choice of model structure, for experiment design, and for accuracy verification. The method is implemented in the Matlab toolkit Senstools. The method and the presentation have been developed with generally preferred learning styles in mind...

  4. 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

  5. Multibeam scanning electron microscope : Experimental results

    NARCIS (Netherlands)

    Mohammadi-Gheidari, A.; Hagen, C.W.; Kruit, P.

    2010-01-01

    The authors present the first results obtained with their multibeam scanning electron microscope. For the first time, they were able to image 196 (array of 14×14) focused beams of a multielectron beam source on a specimen using single beam scanning electron microscope (SEM) optics. The system

  6. Measuring forces in liver cutting: new equipment and experimental results.

    Science.gov (United States)

    Chanthasopeephan, Teeranoot; Desai, Jaydev P; Lau, Alan C W

    2003-12-01

    We are interested in modeling the liver cutting process as accurately as possible by determining the mechanical properties experimentally and developing a predictive model that is self-consistent with the experimentally determined properties. In this paper, we present the newly developed hardware and software to characterize the mechanical response of pig liver during (ex vivo) cutting. We describe the custom-made cutting apparatus, the data acquisition system, and the characteristics of the cutting force versus displacement plot. The force-displacement behavior appears to reveal that the cutting process consists of a sequence of intermittent localized crack extension in the tissue on the macroscopic scale. The macroscopic cutting force-displacement curve shows repeating self-similar units of localized linear loading followed by sudden unloading. The sudden unloading coincides with observed onset of localized crack growth. This experimental data were used to determine the self-consistent local effective Young's modulus for the specimens, to be used in finite element models. Results from finite element analyses models reveal that the magnitude of the self-consistent local effective Young's modulus determined by plane-stress and plane-strain varies within close bounds. Finally, we have also observed that the local effective Young's modulus determined by plane stress and plane strain analysis decreases with increasing cutting speed.

  7. Experimental results from the TUMAN 3 tokamak

    International Nuclear Information System (INIS)

    Golant, V.E.; Andrejko, M.V.; Askinazi, L.G.; Korneev, V.A.; Krikunov, S.V.; Lipin, B.M.; Lebedev, S.V.; Levin, L.S.; Podushnikova, K.A.; Razdobarin, G.T.; Rozhansky, V.A.; Rozhdestvensky, V.V.; Tendler, M.; Tukachinsky, A.S.; Jaroshevich, S.P.

    1995-01-01

    The open-quote open-quote TUMAN-3 close-quote close-quote Tokamak programme concentrates on issues of improved confinement. In 1989 the transition from an ordinary Ohmic regime into an improved confinement mode was achieved. The signatures of the H-mode in auxiliary heated tokamaks have been observed in this regime. The crucial role of the boundary radial electric field was found in the experiments with internal bias probe. Other techniques were demonstrated to disturb the boundary plasma which led to H-mode triggering: short increase of working gas puffing, minor radius magnetic compression and pellet injection. The role scaling of the energy confinement time in the Ohmic H-mode was obtained, which differs dramatically from the scaling for the ordinary Ohmic regime. There were found a strong dependence of τ E on plasma current and a weak dependence on density. The maximum value of τ E was 10 times longer than in the ordinary Ohmic region. The τ E scaling for the Ohmic H-mode is consistent with the scaling proposed for devices with powerful auxiliary heating. The results shows that H-mode physics is universal in tokamaks with different geometries and heating methods. (AIP) copyright 1995 American Institute of Physics

  8. Master function for the solid:solution equilibrium of DOC in taiga and tundra soils of N. Russia: experimental and modeling results

    Science.gov (United States)

    Oosterwoud, M. R.; van der Zee, S. E. A. T. M.; Meeussen, J. C. L.; Temminghoff, E. J. M.

    2012-04-01

    The formation and degradation of Dissolved Organic Carbon (DOC) in arctic environments is intensively investigated, in the context of DOC loading of arctic rivers and seas as well as climate change. However, chemical interaction studies are more scarce, in particular those involving modeling. We investigated DOC interactions in N. Russian taiga and tundra soils, and found that water extractable organic carbon (WEOC) comprises only a small fraction of total organic carbon, whereas DOC is again a small fraction of WEOC. The chemical composition of DOC in terms of humic, fulvic, and hydrophilic acids, the concentrations of dominant cations such as Ca and Al, and the solid iron oxide contents appear to differ profoundly for different soil horizons, as well as between taiga and tundra soils. To reconcile these differences, we processed the data with a simple Freundlich model and with advanced LCD (Ligand and Charge Distribution) modeling of DOC interactions. In the LCD modeling, a combination is made of advances such as CD-MUSIC, and Nica-Donnan approaches, that are implemented in the software ORCHESTRA (though adjusted for computational stability by us). To avoid fitting without good foundation, use is made of the generic parameterization of LCD in combination with measured, site-specific chemical data such as concentrations. We observe that the soil samples from both regions, soil types and horizons can be described with a single DOC sorption Freundlich isotherm. More interestingly, for the same set of samples, the LCD modeling enables us to cast DOC sorption into a single Master Function, that takes iron oxide content and Al and Ca concentrations of soil samples into account in a purely predictive way. Based on this Master Function, it is feasible to assess how DOC is sorbed onto the solid surface. In combination with DOC production and degradation models, our results provide a more balanced instrument to address changes in DOC loading to surface waters due to

  9. Two-channel analysis of QUELL experimental results

    CERN Document Server

    Bottura, L; Rosso, C

    2000-01-01

    We have improved the model presently used in the thermo-hydraulic code Gandalf, adapting it to cable-in-conduit conductors with central cooling channel such as those developed for the model coils of ITER. In particular the helium flow in an arbitrary number of parallel channels have now independent velocity and thermodynamic state (pressure and temperature). We demonstrate the capability of the new model by means of comparison to measurements taken during the QUELL experiment in SULTAN. We compare in particular data on heat slug at zero current and field in a broad range of energy inputs, as well as data on quench propagation, to simulation results obtained with the single channel approximation and the newly implemented two-channel model. The latter achieves significantly better agreement with experimental data, in particular in the case of slow heating transients such as in heat slug propagation tests. (10 refs).

  10. Low-dose benznidazole treatment results in parasite clearance and attenuates heart inflammatory reaction in an experimental model of infection with a highly virulent Trypanosoma cruzi strain.

    Science.gov (United States)

    Cevey, Ágata Carolina; Mirkin, Gerardo Ariel; Penas, Federico Nicolás; Goren, Nora Beatriz

    2016-04-01

    Chagas disease, caused by Trypanosoma cruzi, is the main cause of dilated cardiomyopathy in the Americas. Antiparasitic treatment mostly relies on benznidazole (Bzl) due to Nifurtimox shortage or unavailability. Both induce adverse drug effects (ADE) of varied severity in many patients, leading to treatment discontinuation or abandonment. Since dosage may influence ADE, we aimed to assess Bzl efficacy in terms of parasiticidal and anti-inflammatory activity, using doses lower than those previously reported. BALB/c mice infected with the T. cruzi RA strain were treated with different doses of Bzl. Parasitaemia, mortality and weight change were assessed. Parasite load, tissue infiltrates and inflammatory mediators were studied in the heart. Serum creatine kinase (CK) activity was determined as a marker of heart damage. The infection-independent anti-inflammatory properties of Bzl were studied in an in vitro model of LPS-treated cardiomyocyte culture. Treatment with 25 mg/kg/day Bzl turned negative the parasitological parameters, induced a significant decrease in IL-1β, IL-6 and NOS2 in the heart and CK activity in serum, to normal levels. No mortality was observed in infected treated mice. Primary cultured cardiomyocytes treated with Bzl showed that inflammatory mediators were reduced via inhibition of the NF-κB pathway. A Bzl dose lower than that previously reported for treatment of experimental Chagas disease exerts adequate antiparasitic and anti-inflammatory effects leading to parasite clearance and tissue healing. This may be relevant to reassess the dose currently used for the treatment of human Chagas disease, aiming to minimize ADE.

  11. Low-dose benznidazole treatment results in parasite clearance and attenuates heart inflammatory reaction in an experimental model of infection with a highly virulent Trypanosoma cruzi strain

    Directory of Open Access Journals (Sweden)

    Ágata Carolina Cevey

    2016-04-01

    Full Text Available Chagas disease, caused by Trypanosoma cruzi, is the main cause of dilated cardiomyopathy in the Americas. Antiparasitic treatment mostly relies on benznidazole (Bzl due to Nifurtimox shortage or unavailability. Both induce adverse drug effects (ADE of varied severity in many patients, leading to treatment discontinuation or abandonment. Since dosage may influence ADE, we aimed to assess Bzl efficacy in terms of parasiticidal and anti-inflammatory activity, using doses lower than those previously reported. BALB/c mice infected with the T. cruzi RA strain were treated with different doses of Bzl. Parasitaemia, mortality and weight change were assessed. Parasite load, tissue infiltrates and inflammatory mediators were studied in the heart. Serum creatine kinase (CK activity was determined as a marker of heart damage. The infection-independent anti-inflammatory properties of Bzl were studied in an in vitro model of LPS-treated cardiomyocyte culture. Treatment with 25 mg/kg/day Bzl turned negative the parasitological parameters, induced a significant decrease in IL-1β, IL-6 and NOS2 in the heart and CK activity in serum, to normal levels. No mortality was observed in infected treated mice. Primary cultured cardiomyocytes treated with Bzl showed that inflammatory mediators were reduced via inhibition of the NF-κB pathway. A Bzl dose lower than that previously reported for treatment of experimental Chagas disease exerts adequate antiparasitic and anti-inflammatory effects leading to parasite clearance and tissue healing. This may be relevant to reassess the dose currently used for the treatment of human Chagas disease, aiming to minimize ADE.

  12. Thermodynamics of binary mixtures of N-methyl-2-pyrrolidinone and ketone. Experimental results and modelling of the (solid + liquid) equilibrium and the (vapour + liquid) equilibrium. The modified UNIFAC (Do) model characterization

    Energy Technology Data Exchange (ETDEWEB)

    Domanska, Urszula [Faculty of Chemistry, Physical Chemistry Division, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw (Poland)]. E-mail: Ula@ch.pw.edu.pl; Lachwa, Joanna [Faculty of Chemistry, Physical Chemistry Division, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw (Poland)

    2005-07-15

    The (solid + liquid) equilibrium (SLE) of eight binary systems containing N-methyl-2-pyrrolidinone (NMP) with (2-propanone, or 2-butanone, or 2-pentanone, or 3-pentanone, or cyclopentanone, or 2-hexanone, or 4-methyl-2-pentanone, or 3-heptanone) were carried out by using a dynamic method from T = 200 K to the melting point of the NMP. The isothermal (vapour + liquid) equilibrium data (VLE) have been measured for three binary mixtures of NMP with 2-propanone, 3-pentanone and 2-hexanone at pressure range from p = 0 kPa to p = 115 kPa. Data were obtained at the temperature T = 333.15 K for the first system and at T = 373.15 K for the second two systems. The experimental results of SLE have been correlated using the binary parameters Wilson, UNIQUAC ASM and two modified NRTL equations. The root-mean-square deviations of the solubility temperatures for all the calculated values vary from (0.32 K to 0.68 K) and depend on the particular equation used. The data of VLE were correlated with one to three parameters in the Redlich-Kister expansion. Binary mixtures of NMP with (2-propanone, or 2-butanone, or 2-pentanone, or 3-pentanone, or cyclopentanone, or 2-hexanone, or 4-methyl-2-pentanone, or 3-heptanone) have been investigated in the framework of the modified UNIFAC (Do) model. The reported new interaction parameters for NMP-group (c-CONCH{sub 3}) and carbonyl group ( C=O) let the model consistently described a set of thermodynamic properties, including (solid + liquid) equilibrium (vapour + liquid) equilibrium, excess Gibbs energy and molar excess enthalpies of mixing. Our experimental and literature data of binary mixtures containing NMP and ketones were compared with the results of prediction with the modified UNIFAC (Do) model.

  13. Thermodynamics of binary mixtures of N-methyl-2-pyrrolidinone and ketone. Experimental results and modelling of the (solid + liquid) equilibrium and the (vapour + liquid) equilibrium. The modified UNIFAC (Do) model characterization

    International Nuclear Information System (INIS)

    Domanska, Urszula; Lachwa, Joanna

    2005-01-01

    The (solid + liquid) equilibrium (SLE) of eight binary systems containing N-methyl-2-pyrrolidinone (NMP) with (2-propanone, or 2-butanone, or 2-pentanone, or 3-pentanone, or cyclopentanone, or 2-hexanone, or 4-methyl-2-pentanone, or 3-heptanone) were carried out by using a dynamic method from T = 200 K to the melting point of the NMP. The isothermal (vapour + liquid) equilibrium data (VLE) have been measured for three binary mixtures of NMP with 2-propanone, 3-pentanone and 2-hexanone at pressure range from p = 0 kPa to p = 115 kPa. Data were obtained at the temperature T = 333.15 K for the first system and at T = 373.15 K for the second two systems. The experimental results of SLE have been correlated using the binary parameters Wilson, UNIQUAC ASM and two modified NRTL equations. The root-mean-square deviations of the solubility temperatures for all the calculated values vary from (0.32 K to 0.68 K) and depend on the particular equation used. The data of VLE were correlated with one to three parameters in the Redlich-Kister expansion. Binary mixtures of NMP with (2-propanone, or 2-butanone, or 2-pentanone, or 3-pentanone, or cyclopentanone, or 2-hexanone, or 4-methyl-2-pentanone, or 3-heptanone) have been investigated in the framework of the modified UNIFAC (Do) model. The reported new interaction parameters for NMP-group (c-CONCH 3 ) and carbonyl group ( C=O) let the model consistently described a set of thermodynamic properties, including (solid + liquid) equilibrium (vapour + liquid) equilibrium, excess Gibbs energy and molar excess enthalpies of mixing. Our experimental and literature data of binary mixtures containing NMP and ketones were compared with the results of prediction with the modified UNIFAC (Do) model

  14. Perturbative studies of toroidal momentum transport using neutral beam injection modulation in the Joint European Torus: Experimental results, analysis methodology, and first principles modeling

    DEFF Research Database (Denmark)

    Mantica, P.; Tala, T.; Ferreira, J.S.

    2010-01-01

    Perturbative experiments have been carried out in the Joint European Torus [Fusion Sci. Technol. 53(4) (2008)] in order to identify the diffusive and convective components of toroidal momentum transport. The torque source was modulated either by modulating tangential neutral beam power...... or by modulating in antiphase tangential and normal beams to produce a torque perturbation in the absence of a power perturbation. The resulting periodic perturbation in the toroidal rotation velocity was modeled using time-dependent transport simulations in order to extract empirical profiles of momentum...

  15. Prospects of experimentally reachable beyond Standard Model ...

    Indian Academy of Sciences (India)

    2016-01-06

    Jan 6, 2016 ... Dirac mass MH = ±M + μS/2. As μS does not play much role in any other prediction, we assume that it fits the neutrino oscillation data and one can determine it by inverting the inverse see-saw formula and using experimental results of neutrino masses and mixings. The model achieves precision gauge ...

  16. Experimental results from plasma transport on Prototype-Material Plasma Exposure eXperiment and comparison with B2-Eirene modeling

    Science.gov (United States)

    Kafle, N.; Caneses, J. F.; Biewer, T. M.; Owen, L.; Showers, M.; Donovan, D.; Caughman, J. B.; Goulding, R. H.; Rapp, Juergen

    2017-10-01

    Proto-MPEX at ORNL is a linear plasma device that combines a helicon plasma source with additional microwave and RF heating to deliver high plasma heat and particle fluxes to a target. Double Langmuir probes and Thomson scattering are being used to measure local Te and ne at various radial and axial locations. A recently constructed Mach- double probe provides the added capability of simultaneously measuring Te, ne, and Mach number. With this diagnostic, it is possible to infer the plasma flow, particle flux, and convective heat flux at different locations along the plasma column in Proto-MPEX. Preliminary results show Mach numbers of 0.6 and 0.8 in either direction away from the helicon source, and no flow near the source for the case where the peak magnetic field was 1.0 T. In addition, the Thomson Scattering system has been upgraded to measure ne and Te profiles at two axial locations, upstream at the electron heating location and downstream close to the target. Measurements of particle flow and flux profiles, heat flux, and profiles of ne and Te will be discussed. The extensive coverage provided by these diagnostics permits data-constrained B2-Eirene modeling of the entire plasma column, and comparison with results of modeling of high density mode plasmas will be presented. Supported by the US. D.O.E. contract DE-AC05-00OR22725.

  17. Genetic background can result in a marked or minimal effect of gene knockout (GPR55 and CB2 receptor in experimental autoimmune encephalomyelitis models of multiple sclerosis.

    Directory of Open Access Journals (Sweden)

    Sofia Sisay

    Full Text Available Endocannabinoids and some phytocannabinoids bind to CB1 and CB2 cannabinoid receptors, transient receptor potential vanilloid one (TRPV1 receptor and the orphan G protein receptor fifty-five (GPR55. Studies using C57BL/10 and C57BL/6 (Cnr2 (tm1Zim CB2 cannabinoid receptor knockout mice have demonstrated an immune-augmenting effect in experimental autoimmune encephalomyelitis (EAE models of multiple sclerosis. However, other EAE studies in Biozzi ABH mice often failed to show any treatment effect of either CB2 receptor agonism or antagonism on inhibition of T cell autoimmunity. The influence of genetic background on the induction of EAE in endocannabinoid system-related gene knockout mice was examined. It was found that C57BL/6.GPR55 knockout mice developed less severe disease, notably in female mice, following active induction with myelin oligodendrocyte glycoprotein 35-55 peptide. In contrast C57BL/6.CB2 (Cnr2 (Dgen receptor knockout mice developed augmented severity of disease consistent with the genetically and pharmacologically-distinct, Cnr2 (tm1Zim mice. However, when the knockout gene was bred into the ABH mouse background and EAE induced with spinal cord autoantigens the immune-enhancing effect of CB2 receptor deletion was lost. Likewise CB1 receptor and transient receptor potential vanilloid one knockout mice on the ABH background demonstrated no alteration in immune-susceptibility, in terms of disease incidence and severity of EAE, in contrast to that reported in some C57BL/6 mouse studies. Furthermore the immune-modulating influence of GPR55 was marginal on the ABH mouse background. Whilst sedative doses of tetrahydrocannabinol could induce immunosuppression, this was associated with a CB1 receptor rather than a CB2 receptor-mediated effect. These data support the fact that non-psychoactive doses of medicinal cannabis have a marginal influence on the immune response in MS. Importantly, it adds a note of caution for the translational

  18. Excision of sclerocorneal limbus in dogs and resulting clinical events: study of an experimental model Excisão do limbo esclerocorneano de cães e eventos clínicos decorrentes: estudo de um modelo experimental

    Directory of Open Access Journals (Sweden)

    A.T.J. Brunelli

    2006-02-01

    Full Text Available The consequences of complete removal of the sclerocorneal limbus epithelium were evaluated, as well as the model for such, in which n-heptanol and superficial keratectomy were used. The association of n-heptanol and keratectomy allowed a complete excision of stem cells. Moreover, the destruction of these cells led to significant tectonic alterations that could be employed as a feasible model for clinical experimentation of corneal transplantation.As conseqüências da completa remoção do epitélio do limbo esclerocorneano foram avaliadas, bem como o modelo utilizado para tal, em que se empregou o n-heptanol e a ceratectomia superficial. O n-heptanol e a ceratectomia associados possibilitaram a completa excisão das células-tronco. Da destruição dessas células decorrem alterações tectônicas significativas factíveis para estudos dos transplantes de córnea.

  19. Molecular Determinants for Ligand Binding at Serotonin 5-HT2Aand 5-HT2CGPCRs: Experimental Affinity Results Analyzed by Molecular Modeling and Ligand Docking Studies.

    Science.gov (United States)

    Córdova-Sintjago, Tania; Sakhuja, Rajeev; Kondabolu, Krishnakanth; Canal, Clinton E; Booth, Raymond G

    2012-12-15

    Ligands that activate the serotonin 5-HT 2C G protein-coupled receptor (GPCR) may be therapeutic for psychoses, addiction, and other neuropsychiatric disorders. Ligands that are antagonists at the closely related 5-HT 2A GPCR also may treat neuropsychiatric disorders; in contrast, 5-HT 2A activation may cause hallucinations. 5-HT 2C -specific agonist drug design is challenging because 5-HT 2 GPCRs share 80% transmembrane (TM) homology, same second messenger signaling, and no crystal structures are reported. To help delineate molecular determinants underlying differential binding and activation of 5-HT 2 GPCRs, 5-HT 2A , and 5-HT 2C homology models were built from the β 2 -adrenergic GPCR crystal structure and equilibrated in a lipid phosphatidyl choline bilayer performing molecular dynamics simulations. Ligand docking studies at the 5-HT 2 receptor models were conducted with the (2 R , 4 S )- and (2 S , 4 R )-enantiomers of the novel 5-HT 2C agonist/5-HT 2A/2B antagonist trans -4-phenyl- N,N -dimethyl-2-aminotetralin (PAT) and its 4'-chlorophenyl congners. Results indicate PAT-5-HT 2 molecular interactions especially in TM domain V are important for the (2 R , 4 S ) enantiomer, whereas, TM domain VI and VII interactions are more important for the (2 S , 4 R ) enantiomer.

  20. Mercury methylation, export and bioaccumulation in rice agriculture - model results from comparative and experimental studies in 3 regions of the California Delta, USA

    Science.gov (United States)

    Windham-Myers, L.; Fleck, J.; Eagles-Smith, C.; Ackerman, J.

    2013-12-01

    Seasonally flooded wetland ecosystems are often poised for mercury (Hg) methylation, thus becoming sources of methylmercury (MeHg) to in situ and downstream biota. The seasonal flooding associated with cultivation of rice (Oryza sativa) also generates MeHg, which may be stored in sediment or plants, bioaccumulated into fauna, degraded or exported, depending on hydrologic and seasonal conditions. While many U.S. waters are regulated for total Hg concentrations based on fish targets, California's Sacramento-San Joaquin Delta (Delta) will soon implement the first MeHg total maximum daily load (TMDL) control program. Since 2007, a conceptual model (DRERIP-MCM) and several ecosystem-level studies have been advanced to better understand the mechanisms behind Hg methylation, export and bioaccumulation within Delta wetlands, including rice agriculture. Three Delta rice-growing regions (Yolo Bypass, Cosumnes River, Central Delta) of varied soil characteristics, mining influences and hydrology, were monitored over full crop years to evaluate annual MeHg dynamics. In addition to fish tissue Hg accumulation, a broad suite of biogeochemical and hydrologic indices were assessed and compared between wetland types, seasons, and regions. In general, Delta rice fields were found to export MeHg during the post-harvest winter season, and promote MeHg uptake in fish and rice grain during the summer growing season. As described in a companion presentation (Eagles-Smith et al., this session), the experimental Cosumnes River study suggests that rice-derived dissolved organic carbon (DOC) fuels MeHg production and uptake into aquatic foodwebs. Explicit DRERIP-MCM linkages for the role of rice-DOC in MeHg production, export and bioaccumulation were verified across two summers (2011, 2012): rice biomass and root productivity influenced porewater DOC availability and microbial processes, which drove sediment MeHg production and flux to surface water, promoting MeHg bioaccumulation in fish

  1. Electrochemical desalination of bricks - Experimental and modeling

    DEFF Research Database (Denmark)

    Skibsted, Gry; Ottosen, Lisbeth M.; Jensen, Pernille Erland

    2015-01-01

    Chlorides, nitrates and sulfates play an important role in the salt-decay of porous materials in buildings and monuments. Electrochemical desalination is a technology able to remove salts from such porous materials in order to stop or prevent the decay. In this paper, experimental and numerical......-contaminated bricks with respect to the monovalent ions is discussed. Comparison between the experimental and the simulation results showed that the proposed numerical model is able to predict electrochemical desalination treatments with remarkable accuracy, and it can be used as a predictive tool...

  2. Insulator-based dielectrophoresis of microorganisms: theoretical and experimental results.

    Science.gov (United States)

    Moncada-Hernandez, Hector; Baylon-Cardiel, Javier L; Pérez-González, Victor H; Lapizco-Encinas, Blanca H

    2011-09-01

    Dielectrophoresis (DEP) is the motion of particles due to polarization effects in nonuniform electric fields. DEP has great potential for handling cells and is a non-destructive phenomenon. It has been utilized for different cell analysis, from viability assessments to concentration enrichment and separation. Insulator-based DEP (iDEP) provides an attractive alternative to conventional electrode-based systems; in iDEP, insulating structures are used to generate nonuniform electric fields, resulting in simpler and more robust devices. Despite the rapid development of iDEP microdevices for applications with cells, the fundamentals behind the dielectrophoretic behavior of cells has not been fully elucidated. Understanding the theory behind iDEP is necessary to continue the progress in this field. This work presents the manipulation and separation of bacterial and yeast cells with iDEP. A computational model in COMSOL Multiphysics was employed to predict the effect of direct current-iDEP on cells suspended in a microchannel containing an array of insulating structures. The model allowed predicting particle behavior, pathlines and the regions where dielectrophoretic immobilization should occur. Experimental work was performed at the same operating conditions employed with the model and results were compared, obtaining good agreement. This is the first report on the mathematical modeling of the dielectrophoretic response of yeast and bacterial cells in a DC-iDEP microdevice. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Exploring the performance of the SEDD model to predict sediment yield in eucalyptus plantations. Long-term results from an experimental catchment in Southern Italy

    Science.gov (United States)

    Porto, P.; Cogliandro, V.; Callegari, G.

    2018-01-01

    In this paper, long-term sediment yield data, collected in a small (1.38 ha) Calabrian catchment (W2), reafforested with eucalyptus trees (Eucalyptus occidentalis Engl.) are used to validate the performance of the SEdiment Delivery Distributed Model (SEDD) in areas with high erosion rates. At first step, the SEDD model was calibrated using field data collected in previous field campaigns undertaken during the period 1978-1994. This first phase allowed the model calibration parameter β to be calculated using direct measurements of rainfall, runoff, and sediment output. The model was then validated in its calibrated form for an independent period (2006-2016) for which new measurements of rainfall, runoff and sediment output are also available. The analysis, carried out at event and annual scale showed good agreement between measured and predicted values of sediment yield and suggested that the SEDD model can be seen as an appropriate means of evaluating erosion risk associated with manmade plantations in marginal areas. Further work is however required to test the performance of the SEDD model as a prediction tool in different geomorphic contexts.

  4. Review of experimental models: sinusitis in rabbits

    Directory of Open Access Journals (Sweden)

    André Coura Perez

    2014-10-01

    Full Text Available INTRODUCTION: In order to better understand the pathophysiology of rhinosinusitis, several attempts have been made to create the disease in an animal model. Among the studied rodents each has its advantages and disadvantages. Rabbits are considered more appropriate for studies that require surgical manipulation or invasive procedures. OBJECTIVES: To evaluate the most viable experimental model of rhinosinusitis in rabbits to be adopted in future studies. METHODS: An electronic search for studies with experimental models of rhinosinusitis in rabbits published in English and Portuguese between July of 1967 and January of 2013 was conducted in Medline, Pub Med, Cochrane, and CAPES databases, using the keywords "sinusitis", "rabbits", and "polyps". RESULTS: A total of 256 studies were retrieved, but in accordance with the inclusion and exclusion criteria, only ten studies were selected. Many different methods of response assessment were used in these studies. CONCLUSION: To date, there is no ideal experimental model for induction of acute or chronic rhinosinusitis in rabbits, but the rhinogenic model appears to be the most viable option for the continuity of studies of the disease.

  5. Bridge-in-a-backpack(TM) : task 3.2: investigating soil - structure interaction - modeling and experimental results of steel arches.

    Science.gov (United States)

    2015-07-01

    This report includes fulfillment of Task 3.2 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 3 is an investigation of soil-structure interaction for the FRP tubes. Task 3.2 is the : modeling ...

  6. Bridge-in-a-backpack(TM) task 3.3 : investigate soil-structure interaction-modeling and experimental results of concrete filled FRP tube arches.

    Science.gov (United States)

    2015-12-01

    This report includes fulfillment of Task 3.3 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 3 is an investigation of soil-structure interaction for the FRP tubes. Task 3.3 is the : modeling ...

  7. Dermal uptake directly from air under transient conditions: advances in modeling and comparisons with experimental results for human subjects

    DEFF Research Database (Denmark)

    Morrison, G C; Weschler, Charles J.; Bekö, Gabriel

    2016-01-01

    transfer of SVOCs to sinks like clothing or clean air. We test the model by simulating di-ethyl phthalate (DEP) and di-n-butyl phthalate (DnBP) exposures of six bare-skinned (Weschler et al. 2015, Environ. Health Perspect., 123, 928) and one clothed participant (Morrison et al. 2016, J. Expo. Sci. Environ...

  8. Intrabody application of eptotermin alpha enhances bone formation in osteoporotic fractures of the lumbar spine; however, fails to increase biomechanical stability - results of an experimental sheep model.

    Science.gov (United States)

    Eschler, Anica; Roepenack, Paula; Herlyn, Philipp Karl Ewald; Roesner, Jan; Martin, Heiner; Vollmar, Brigitte; Mittlmeier, Thomas; Gradl, Georg

    2015-01-01

    This study analyses the effect of eptotermin α application into fractured vertebrae. It is hypothesized that eptotermin α is capable to enhance bony healing of the osteoporotic spine. In 10 Merino sheep osteoporosis induction was performed by ovariectomy, corticosteroid therapy and calcium/phosphorus/vitamin D-deficient diet; followed by standardized creation of lumbar vertebral compression fractures (VCFs) type A3.1 and consecutive fracture reduction/fixation using expandable mesh cages. Randomly, intravertebral eptotermin α (G1) or no augmentation was added (G2). Macroscopic, micro-CT, and biomechanical evaluation assessed bony consolidation two months postoperatively: Micro-CT data revealed bony consolidation for all cases with significant increased callus development for G2 (60%) and BV/TV (bone volume/total volume 73.45%, osteoporotic vertebrae 35.76%). Neither group showed improved biomechanical stability. Eptotermin α enhanced mineralisation in VCFs in an experimental setup with use of cementless augmentation via an expandable cage. However, higher bone mineral density did not lead to superior biomechanical properties.

  9. Experimental Results and Model Calculations of a Hybrid Adsorption-Compression Heat Pump Based on a Roots Compressor and Silica Gel-Water Sorption

    Energy Technology Data Exchange (ETDEWEB)

    Van der Pal, M.; De Boer, R.; Wemmers, A.K.; Smeding, S.F.; Veldhuis, J.B.J.; Lycklama a Nijeholt, J.A.

    2013-10-15

    Thermally driven sorption systems can provide significant energy savings, especially in industrial applications. The driving temperature for operation of such systems limits the operating window and can be a barrier for market-introduction. By adding a compressor, the sorption cycle can be run using lower waste heat temperatures. ECN has recently started the development of such a hybrid heat pump. The final goal is to develop a hybrid heat pump for upgrading lower (<100C) temperature industrial waste heat to above pinch temperatures. The paper presents the first measurements and model calculations of a hybrid heat pump system using a water-silica gel system combined with a Roots type compressor. From the measurements can be seen that the effect of the compressor is dependent on where in the cycle it is placed. When placed between the evaporator and the sorption reactor, it has a considerable larger effect compared to the compressor placed between the sorption reactor and the condenser. The latter hardly improves the performance compared to purely heat-driven operation. This shows the importance of studying the interaction between all components of the system. The model, which shows reasonable correlation with the measurements, could proof to be a valuable tool to determine the optimal hybrid heat pump configuration.

  10. Selected Experimental Results from Heavy-Ion Collisions at LHC

    Directory of Open Access Journals (Sweden)

    Ranbir Singh

    2013-01-01

    Full Text Available We review a subset of experimental results from the heavy-ion collisions at the Large Hadron Collider (LHC facility at CERN. Excellent consistency is observed across all the experiments at the LHC (at center of mass energy sNN=2.76 TeV for the measurements such as charged particle multiplicity density, azimuthal anisotropy coefficients, and nuclear modification factor of charged hadrons. Comparison to similar measurements from the Relativistic Heavy Ion Collider (RHIC at lower energy (sNN=200 GeV suggests that the system formed at LHC has a higher energy density and larger system size and lives for a longer time. These measurements are compared to model calculations to obtain physical insights on the properties of matter created at the RHIC and LHC.

  11. First experimental application of bevacizumab-eluting PC coated stent for inhibition of vasa vasorum of atherosclerotic plaque: angiographic results in a rabbit atheromatic model.

    Science.gov (United States)

    Stefanadis, Christodoulos; Toutouzas, Konstantinos; Stefanadi, Elli; Kolodgie, Frank; Virmani, Renu; Kipshidze, Nicholas

    2006-01-01

    Atheromatosis is associated with angiogenesis, through the development of a dense net of vasa vasorum. The role of vascular endothelial growth factor (VEGF) is important in this process. Bevacizumab, an antibody specific for VEGF, has recently been applied in the clinical field. We hypothesized that local delivery of bevacizumab by stent would inhibit the development of vasa vasorum at the stented arterial segment in an atheromatic rabbit model. We used 10 New Zealand rabbits under atherogenic diet for 3 weeks. We immersed a BiodivYsio stent into a solution of 4 ml bevacizumab as in previous studies. Both eluting stents and non-eluting BiodivYsio stents were implanted in the middle segment of the 2 iliac arteries of the animals, with the same procedural characteristics. Sacrifice following repeat angiogram was scheduled after 28 days. In all animals the procedure of stent loading with bevacizumab and stent implantation was successful. There was no acute or subacute thrombosis. Iliac artery lumen diameters before and immediately after stent placement were similar in all stent treatment groups. At euthanasia stent lumen diameters were similar in all groups. All stents were angiographically patent at the time of euthanasia without aneurysm formation. Moreover, gross pathologic analysis did not show any evidence of vascular necrosis. Bevacizumab-eluting stent implantation in atheromatic rabbit iliac arteries is feasible and safe. This new approach for the treatment of stable and vulnerable plaques needs to be further investigated.

  12. An academic hospitalist model to improve healthcare worker communication and learner education: Results from a quasi-experimental study at a veterans affairs medical center

    Science.gov (United States)

    Saint, Sanjay; Fowler, Karen E; Krein, Sarah L; Flanders, Scott A; Bodnar, Timothy W; Young, Eric; Moseley, Richard H

    2013-01-01

    BACKGROUND Although hospitalists may improve efficiency and quality of inpatient care, their effect on healthcare-worker communication and education has been less well-studied. OBJECTIVE To test various approaches to improving healthcare-worker communication and learner education within the context of a newly designed academic hospital medicine program. DESIGN Before-and-after design with concurrent control group. SETTING A Midwestern Veterans Affairs medical center. INTERVENTION Multimodal systems redesign of 1 of 4 medical teams (Gold team) that included clinical modifications (change in rounding structure, with inclusion of nurses, a Clinical Care Coordinator, and a pharmacist) and educational interventions (providing explicit expectations of learners and providing a reading list for both learners and attending physicians). MEASUREMENTS Number of admissions, length of stay, readmissions, house officer and medical student ratings of attendings' teaching, medical student internal medicine National Board of Medical Examiners Subject Examination (“shelf” exam) scores, and clinical staff surveys. RESULTS Length of stay was reduced by about 0.3 days on all teams after the initiative began (P = 0.004), with no significant differences between Gold and non-Gold teams. The majority of physicians (83%) and nurses (68%) felt that including nurses during rounds improved healthcare-worker communication; significantly more nurses were satisfied with communication with the Gold team than with the other teams (71% vs 53%; P = 0.02). Gold attendings generally received higher teaching scores compared with non-Gold attendings, and third-year medical students on the Gold team scored significantly higher on the shelf exam compared with non–Gold team students (84 vs 82; P = 0.006). CONCLUSIONS Academic hospitalists working within a systems redesign intervention were able to improve healthcare-worker communication and enhance learner education without increasing

  13. Experimental Data in Vehicle Modeling

    Directory of Open Access Journals (Sweden)

    Tomasikova Maria

    2017-05-01

    Full Text Available This article is about a vehicle model which is created in software Matlab Simscape Driveline. In this model the motor is created like a subsystem by Simulink blocks and input data were measured by single roller dynamometer for cars (SRD. Measured data are the input into the model by Lookup Table block. The vehicle model is made by gear, differential, tire and vehicle body blocks. We studied the forces on tires, the vehicle velocity and the slip.

  14. Injury Based on Its Study in Experimental Models

    Directory of Open Access Journals (Sweden)

    M. Mendes-Braz

    2012-01-01

    Full Text Available The present review focuses on the numerous experimental models used to study the complexity of hepatic ischemia/reperfusion (I/R injury. Although experimental models of hepatic I/R injury represent a compromise between the clinical reality and experimental simplification, the clinical transfer of experimental results is problematic because of anatomical and physiological differences and the inevitable simplification of experimental work. In this review, the strengths and limitations of the various models of hepatic I/R are discussed. Several strategies to protect the liver from I/R injury have been developed in animal models and, some of these, might find their way into clinical practice. We also attempt to highlight the fact that the mechanisms responsible for hepatic I/R injury depend on the experimental model used, and therefore the therapeutic strategies also differ according to the model used. Thus, the choice of model must therefore be adapted to the clinical question being answered.

  15. Excess molar volumes and excess molar enthalpies of binary and ternary mixtures of 1-butanol, a tertiary amine (tri-n-butylamine or tri-n-octylamine) and n-hexane: Experimental results and ERAS-model calculations

    Energy Technology Data Exchange (ETDEWEB)

    Kwaterski, Matthias [Applied Thermodynamics, Institute of Physical Chemistry, University of Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg (Germany); Rezanova, Elena N. [Applied Thermodynamics, Institute of Physical Chemistry, University of Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg (Germany); Lichtenthaler, Ruediger N. [Applied Thermodynamics, Institute of Physical Chemistry, University of Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg (Germany)]. E-mail: R.Lichtenthaler@urz.uni-heidelberg.de

    2006-10-15

    Experimental data at T=298.15K and ambient pressure of excess molar volumes V{sub m}{sup E} and excess molar enthalpies H{sub m}{sup E} are reported for two ternary and the corresponding binary mixtures of {l_brace}1-butanol, tri-n-butylamine (TBA), or tri-n-octylamine (TOA), and n-hexane{r_brace}. A vibrating-tube densitometer was used to determine V{sub m}{sup E}. H{sub m}{sup E} was measured using a quasi-isothermal flow calorimeter. The experimental results are used to test the applicability of the ERAS model for describing both thermodynamic excess properties of ternary mixtures containing an alkanol, a tertiary amine and an n-alkane. Qualitative agreement of calculated values with experimental results was achieved using only system-specific parameters determined from binary mixtures. The results are explained in terms of the self-association between alkanol molecules, cross-association between the alkanol and the tertiary amines and structural effects.

  16. Experimental "evolutional machines": mathematical and experimental modeling of biological evolution

    Science.gov (United States)

    Brilkov, A. V.; Loginov, I. A.; Morozova, E. V.; Shuvaev, A. N.; Pechurkin, N. S.

    Experimentalists possess model systems of two major types for study of evolution continuous cultivation in the chemostat and long-term development in closed laboratory microecosystems with several trophic structure If evolutionary changes or transfer from one steady state to another in the result of changing qualitative properties of the system take place in such systems the main characteristics of these evolution steps can be measured By now this has not been realized from the point of view of methodology though a lot of data on the work of both types of evolutionary machines has been collected In our experiments with long-term continuous cultivation we used the bacterial strains containing in plasmids the cloned genes of bioluminescence and green fluorescent protein which expression level can be easily changed and controlled In spite of the apparent kinetic diversity of evolutionary transfers in two types of systems the general mechanisms characterizing the increase of used energy flow by populations of primer producent can be revealed at their study According to the energy approach at spontaneous transfer from one steady state to another e g in the process of microevolution competition or selection heat dissipation characterizing the rate of entropy growth should increase rather then decrease or maintain steady as usually believed The results of our observations of experimental evolution require further development of thermodynamic theory of open and closed biological systems and further study of general mechanisms of biological

  17. Surface physics theoretical models and experimental methods

    CERN Document Server

    Mamonova, Marina V; Prudnikova, I A

    2016-01-01

    The demands of production, such as thin films in microelectronics, rely on consideration of factors influencing the interaction of dissimilar materials that make contact with their surfaces. Bond formation between surface layers of dissimilar condensed solids-termed adhesion-depends on the nature of the contacting bodies. Thus, it is necessary to determine the characteristics of adhesion interaction of different materials from both applied and fundamental perspectives of surface phenomena. Given the difficulty in obtaining reliable experimental values of the adhesion strength of coatings, the theoretical approach to determining adhesion characteristics becomes more important. Surface Physics: Theoretical Models and Experimental Methods presents straightforward and efficient approaches and methods developed by the authors that enable the calculation of surface and adhesion characteristics for a wide range of materials: metals, alloys, semiconductors, and complex compounds. The authors compare results from the ...

  18. 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

  19. 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.

  20. 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. .

  1. Dynamic vehicle model for handling performance using experimental data

    Directory of Open Access Journals (Sweden)

    SangDo Na

    2015-11-01

    Full Text Available An analytical vehicle model is essential for the development of vehicle design and performance. Various vehicle models have different complexities, assumptions and limitations depending on the type of vehicle analysis. An accurate full vehicle model is essential in representing the behaviour of the vehicle in order to estimate vehicle dynamic system performance such as ride comfort and handling. An experimental vehicle model is developed in this article, which employs experimental kinematic and compliance data measured between the wheel and chassis. From these data, a vehicle model, which includes dynamic effects due to vehicle geometry changes, has been developed. The experimental vehicle model was validated using an instrumented experimental vehicle and data such as a step change steering input. This article shows a process to develop and validate an experimental vehicle model to enhance the accuracy of handling performance, which comes from precise suspension model measured by experimental data of a vehicle. The experimental force data obtained from a suspension parameter measuring device are employed for a precise modelling of the steering and handling response. The steering system is modelled by a lumped model, with stiffness coefficients defined and identified by comparing steering stiffness obtained by the measured data. The outputs, specifically the yaw rate and lateral acceleration of the vehicle, are verified by experimental results.

  2. Model refinement for offshore platforms: Experimental study

    Science.gov (United States)

    Zhang, Min; Chen, Zongli; Wu, Yanjian

    2017-08-01

    Offshore jacket platforms are widely used in offshore oil and gas exploitation. Finite element models of such structures need to have many degrees of freedom (DOFs) to represent the geometrical detail of complex structures, thereby leading to incompatibility in the number of DOFs of experimental models. To bring them both to the same order while ensuring that the essential eigen- properties of the refined model match those of experimental models, an extended model refinement procedure is presented in this paper. Vibration testing of an offshore jacket platform model is performed to validate the applicability of the proposed approach. A full-order finite element model of the platform is established and then tuned to meet the measured modal properties identified from the acceleration signals. Both model reduction and modal expansion methods are investigated, as well as various scenarios of sensor arrangements. Upon completion of the refinement, the updated jacket platform model matches the natural frequencies of the measured model well.

  3. 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.)

  4. Experimental models of demyelination and remyelination.

    Science.gov (United States)

    Torre-Fuentes, L; Moreno-Jiménez, L; Pytel, V; Matías-Guiu, J A; Gómez-Pinedo, U; Matías-Guiu, J

    2017-08-29

    Experimental animal models constitute a useful tool to deepen our knowledge of central nervous system disorders. In the case of multiple sclerosis, however, there is no such specific model able to provide an overview of the disease; multiple models covering the different pathophysiological features of the disease are therefore necessary. We reviewed the different in vitro and in vivo experimental models used in multiple sclerosis research. Concerning in vitro models, we analysed cell cultures and slice models. As for in vivo models, we examined such models of autoimmunity and inflammation as experimental allergic encephalitis in different animals and virus-induced demyelinating diseases. Furthermore, we analysed models of demyelination and remyelination, including chemical lesions caused by cuprizone, lysolecithin, and ethidium bromide; zebrafish; and transgenic models. Experimental models provide a deeper understanding of the different pathogenic mechanisms involved in multiple sclerosis. Choosing one model or another depends on the specific aims of the study. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Experimental summary talk. A summary of the experimental results presented at Moriond QCD 2001

    Energy Technology Data Exchange (ETDEWEB)

    Pietrzyk, B

    2001-06-01

    A summary of the experimental results presented at Moriond QCD 2001 are given. The author reviews results concerning the expected mass of the Higgs boson, the discovery of new particles, heavy-ion collision physics, structure functions, diffractive J/{psi} production, WW physics, heavy flavours and the first results given by BaBar and Belle installations.

  6. Experimental summary talk. A summary of the experimental results presented at Moriond QCD 2001

    International Nuclear Information System (INIS)

    Pietrzyk, B.

    2001-06-01

    A summary of the experimental results presented at Moriond QCD 2001 are given. The author reviews results concerning the expected mass of the Higgs boson, the discovery of new particles, heavy-ion collision physics, structure functions, diffractive J/Ψ production, WW physics, heavy flavours and the first results given by BaBar and Belle installations

  7. Experimental model of lead nephropathy

    Energy Technology Data Exchange (ETDEWEB)

    Khalil-Manesh, F.; Gonick, H.C. (Cedars-Sinai Medical Center, Los Angeles, CA (United States)); Cohen, A. (UCLA-Harbor General Hospital, Torrance, CA (United States)); Bergamaschi, E.; Mutti, A. (Univ. of Parma (Italy))

    1992-06-01

    Male Sprague-Dawley rats were exposed to high-dose (0.5%) lead acetate for periods ranging from 1 to 9 months; then lead exposure was discontinued, and animals were sacrificed after 12 months. Two additional groups of low-dose (0.01%) and high-dose (0.5%) rats were exposed to lead for 6 months, then lead was discontinued and the rats were treated with three 5-day courses of 0.5% DMSA (dimercaptosuccinic acid) over the next 6 months. Low-dose lead-treated rats showed no significant pathological changes with or without DMSA treatment, but exhibited a significant increase in GFR after DMSA. High-dose lead-treated animals showed no functional or pathological changes when lead exposure was discontinued after 1 month. However, when duration of exposure was 6 or 9 months, GFR was decreased and serum creatinine and urea nitrogen were increased as compared to controls. Tubulointerstitial disease was severe. Administration of DMSA resulted in an improvement in GFR and a decrease in albuminuria, together with a reduction in size and number of nuclear inclusion bodies in proximal tubules. However, tubulointerstitial scarring was only minimally reduced. It may be concluded that, except for brief initial exposure, discontinuation of high-dose lead exposure fails to reverse lead-induced renal damage. Treatment with the chelator, DMSA, improves renal function but has less effect on pathological alterations. As GFR improved after DMSA treatment in both low-dose and high-dose lead-treated rats, irrespective of the degree of pathological alterations, it may be concluded that the DMSA effect is most likely mediated by hemodynamic changes.

  8. Improving the physiological realism of experimental models.

    Science.gov (United States)

    Vinnakota, Kalyan C; Cha, Chae Y; Rorsman, Patrik; Balaban, Robert S; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A; Jeneson, Jeroen A L

    2016-04-06

    The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models. Here, the current state of suitable E-models, ranging from in vitro non-human cell organelles to in vivo human organ systems, is discussed. Specifically, challenges and recent progress in improving the physiological realism of E-models that may benefit the VPH project are highlighted and discussed using examples from the field of research on cardiovascular disease, musculoskeletal disorders, diabetes and Parkinson's disease.

  9. 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

  10. Influence of Hydraulic Design on Stability and on Pressure Pulsations in Francis Turbines at Overload, Part Load and Deep Part Load based on Numerical Simulations and Experimental Model Test Results

    International Nuclear Information System (INIS)

    Magnoli, M V; Maiwald, M

    2014-01-01

    Francis turbines have been running more and more frequently in part load conditions, in order to satisfy the new market requirements for more dynamic and flexible energy generation, ancillary services and grid regulation. The turbines should be able to be operated for longer durations with flows below the optimum point, going from part load to deep part load and even speed-no-load. These operating conditions are characterised by important unsteady flow phenomena taking place at the draft tube cone and in the runner channels, in the respective cases of part load and deep part load. The current expectations are that new Francis turbines present appropriate hydraulic stability and moderate pressure pulsations at overload, part load, deep part load and speed-no-load with high efficiency levels at normal operating range. This study presents series of investigations performed by Voith Hydro with the objective to improve the hydraulic stability of Francis turbines at overload, part load and deep part load, reduce pressure pulsations and enlarge the know-how about the transient fluid flow through the turbine at these challenging conditions. Model test measurements showed that distinct runner designs were able to influence the pressure pulsation level in the machine. Extensive experimental investigations focused on the runner deflector geometry, on runner features and how they could reduce the pressure oscillation level. The impact of design variants and machine configurations on the vortex rope at the draft tube cone at overload and part load and on the runner channel vortex at deep part load were experimentally observed and evaluated based on the measured pressure pulsation amplitudes. Numerical investigations were employed for improving the understanding of such dynamic fluid flow effects. As example for the design and experimental investigations, model test observations and pressure pulsation curves for Francis machines in mid specific speed range, around n qopt = 50

  11. EXPERIMENTAL MODEL OF INFESTATION IN OVINE OESTROSIS

    Directory of Open Access Journals (Sweden)

    DANIELA MOŢ

    2007-10-01

    Full Text Available The experimental model was been performed on 20 youth sheep, between 10-11months aged who were divided in two groups. The first group (10 animals containsonly healthy animals and represented the control group. The second group(experimental contains experimental infested animals with Oestrus ovis larvae, offirst stadium of evolution. Each sheep was been inoculated with 30 larvae onintranasal way. After three months from experimental infestation, the animals werebeen slaughtered and was made the necropsy. Were evaluated themorphopathological alterations and were been discovered the Oestrus ovis larvae.From the inoculated larvae 3 months ago were been founded 57.66 %. From these,16 % were on I stadium, 37.33 % II stadium and 4.33 % III stadium of evolution. Noclinical evident sign was observed in experimental infested sheep. This fact is inconcordance with other researchers observations, who demonstrated that theclinical reproduction of disease can be obtain only after 3-4 experimentaladministrations of Oestrus ovis larvae.

  12. Biokinetic models for radionuclides in experimental animals

    International Nuclear Information System (INIS)

    Morcillo, M. A.

    2003-01-01

    The biokinetic models for many radionuclides are, to a large extent, based on data obtained in experimental animals. The methods used in the experimental development of a biokinetic model can be classified in two groups (i) those applied during the experimental work, which include the activity determination of a given radionuclide at different times and in different biological media such as blood, serum, organs/tissues, urine, bile and faeces and (ii) those methods used for the analysis and study of the experimental data, based in mathematical tools. Some of these methods are reviewed,with special emphasis in the whole body macro autoradiography. To conclude, the contribution that this type of studies can have in two fields of radiation protection is discussed, namely optimization of dosimetric evaluations and decorporation of radionuclides. (Author)

  13. Endometriose: modelo experimental em ratas Endometriosis: experimental model in rats

    Directory of Open Access Journals (Sweden)

    Eduardo Schor

    1999-06-01

    that the free portion of the endometrium was directed towards the lumen of the abdominal cavity. After 21 days the animals were again operated to observe the size of the implants and to remove the ectopic endometrium for microscopic analysis. Results: we macroscopically observed a significant growth of the endometrial implants. Microscopic examination showed presence of glandular epithelium and stroma similar to topic epithelium. Conclusion: this model reproduces endometriosis in the female rat allowing a better study of this pathology, mainly the action of drugs on these implants.

  14. Volumetric and viscometric properties of binary mixtures of {l_brace}methyl tert-butyl ether (MTBE) + alcohol{r_brace} at several temperatures and p = 0.1 MPa: Experimental results and application of the ERAS model

    Energy Technology Data Exchange (ETDEWEB)

    Hoga, H.E. [Departamento de Engenharia Quimica, Centro Universitario da FEI, Avenida Humberto de Alencar, Castelo Branco 3972, 09850-901 Sao Bernardo do Campo, Sao Paulo (Brazil); Torres, R.B., E-mail: belchior@fei.edu.br [Departamento de Engenharia Quimica, Centro Universitario da FEI, Avenida Humberto de Alencar, Castelo Branco 3972, 09850-901 Sao Bernardo do Campo, Sao Paulo (Brazil)

    2011-08-15

    Highlights: > Binary mixtures of MTBE + alcohol have been studied. > Volumetric and viscometric properties have been determined at several temperatures. > Excess molar volumes have been used to test the applicability of the ERAS model. > The results are discussed in terms of chemical and structural effects. - Abstract: Densities and viscosities of binary mixtures of {l_brace}methyl tert-butyl ether (MTBE) + methanol, or +ethanol, or +1-propanol, or +2-propanol, or +1-butanol, or +1-pentanol, or +1-hexanol{r_brace} have been determined as a function of composition at several temperatures and atmospheric pressure. The temperatures studied were (293.15, 298.15, 303.15, and 308.15) K. The experimental results have been used to calculate the excess molar volume (V{sub m}{sup E}) and viscosity deviation ({Delta}{eta}). Both V{sub m}{sup E} and {Delta}{eta} values were negative over the entire range of mole fraction for all temperatures and systems studied. Moreover, the V{sub m}{sup E} values have been used to test the applicability of the Extended Real Associated Solution (ERAS) model.

  15. 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.

  16. On collisional disruption - Experimental results and scaling laws

    Science.gov (United States)

    Davis, D. R.; Ryan, E. V.

    1990-01-01

    Both homogeneous and inhomogeneous targets have been addressed by the present experimental consideration of the impact strengths, fragment sizes, and fragment velocities generated by cement mortar targets whose crushing strengths vary by an order of magnitude, upon impact of projectiles in the velocity range of 50-5700 m/sec. When combined with additional published data, dynamic impact strength is found to correlate with quasi-static material strengths for materials ranging in character from basalt to ice; two materials not following this trend, however, are weak mortar and clay targets. Values consistent with experimental results are obtainable with a simple scaling algorithm based on impact energy, material properties, and collisional strain rate.

  17. [Skin defect modeling in experimental animals].

    Science.gov (United States)

    Oleshko, A N; Kornienko, V V; Tkachenko, Yu A; Kurganskaya, V A

    2015-02-01

    To assess the skin regeneration and explore new medical devices for the treatment of skin defects is necessary to conduct long-term experiments using laboratory animals. Currently, there are many methods for skin trauma modeling but most of them have disadvantages that limit their use. The purpose of this work - the development of an experimental model of the formation of skin defect of various etiologies with the specified parameters of depth and area of damage to the absence of systemic effects on the animal's body. We have developed an installation that allows us to form a skin defect of mechanical, thermal and chemical etiology with area from 1.76 cm2 to 2.0 cm2. The experiment was conducted on 18 male laboratory rats to examine the effectiveness of current method and control the depth and area of the defect. As a result of the new methodology, we were able to carry out simulation skin injuries of different etiology on laboratory animals in the short term and reduce the severity of injuries to extend the life span of animals to monitor the repair processes, as well as to standardize the modeling of injuries according to the criteria of area and depth of the defect.

  18. Comparison of Calculated and Experimental Results for a Boiling/Condensing Experimental Facility

    Energy Technology Data Exchange (ETDEWEB)

    Carbajo, Juan J [ORNL; McDuffee, Joel Lee [ORNL; Felde, David K [ORNL

    2016-01-01

    A new experimental facility for materials irradiation and testing at the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) is being developed. Details of this facility have been presented before [1, 2]. A prototype of this facility, the Thermo-Syphon Test Loop (TSTL) has been built and experimental data have been obtained and analyzed [3, 4]. Pre-test calculations for this facility with the RELAP5-3D code [5] have been presented previously [6] as well as other calculations [7, 8] with the TRACE code [9]. The results of both codes were very different [7]. RELAP5-3D predicted much higher pressures and temperatures than TRACE. This paper compares calculated results with the TSTL experimental data.

  19. Experimental Verification of the Transient Model in an Enrichment Circuit

    International Nuclear Information System (INIS)

    Fernandino, Maria; Brasnarof, Daniel; Delmastro, Dario

    2003-01-01

    In the present work an experimental closed loop representing a single stage of an uranium gaseous diffusion enrichment cascade is described, loop that is used to experimentally validate an analytical model that describes the dynamics inside such a loop.The conditions established inside the experimental loop after a few working hours were reproduced by the analytical model, leaving the slower thermal phenomena taking place for future studies.Two kinds of perturbations were experimentally introduced: a change in the range of operation of one of the compressors and the addition of mass into the loop.Numerical and experimental results are compared and presented in this work. The analytical model proposed was verified against these two changes, with very good agreement in the time response and measured values.This analytical model allows us to determine the characteristic time response of the system

  20. Effect of policosanol on experimental thrombosis models.

    Science.gov (United States)

    Carbajal, D; Arruzazabala, M L; Más, R; Molina, V; Valdés, S

    1994-05-01

    Policosanol is a natural product, obtained from sugar cane wax (Saccharum officinarum L.) with which cholesterol-lowering effects have been demonstrated in experimental models, healthy volunteers and hypercholesterolemic patients. The effects of policosanol on experimental venous and arterial thrombosis in rats were investigated. Policosanol (25 mg/kg) significantly decreased the thrombus weight, in the venous thrombosis models, the protective effect persisting until 4 h after its oral administration. Policosanol (25 mg/kg single dose) was able to reduce rectal temperature variation induced by arterial thrombosis. Also at the same dose policosanol increased 6-keto-PGF1 alpha serum levels in rats.

  1. 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...

  2. Chronic irradiation of the gonads of rats: first experimental results

    International Nuclear Information System (INIS)

    Lemaire, Guy; Maas, Jean.

    1979-12-01

    The first experimental results obtained after acute (0.5 MeV neutrons) and chronic ( 60 Co gamma rays) irradiation of male rats are presented. The biological criterion was the weight loss of male gonads a parameter strongly correlated to germ-cell survivals. The purpose of this study was, to determine the RBE of 0.5 MeV neutrons for this particular criterion and to obtain new dynamic equilibrium in the germinal tissue after continuous exposure leading to the determination of the recovery and cell-renewal factors they imply [fr

  3. Experimental and simulational result multipactors in 112 MHz QWR injector

    Energy Technology Data Exchange (ETDEWEB)

    Xin, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ben-Zvi, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Belomestnykh, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Brutus, J. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Skaritka, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wu, Q. [Brookhaven National Lab. (BNL), Upton, NY (United States); Xiao, B. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    The first RF commissioning of 112 MHz QWR superconducting electron gun was done in late 2014. The coaxial Fundamental Power Coupler (FPC) and Cathode Stalk (stalk) were installed and tested for the first time. During this experiment, we observed several multipacting barriers at different gun voltage levels. The simulation work was done within the same range. The comparison between the experimental observation and the simulation results are presented in this paper. The observations during the test are consisted with the simulation predictions. We were able to overcome most of the multipacting barriers and reach 1.8 MV gun voltage under pulsed mode after several round of conditioning processes.

  4. Aromatic interactions impact ligand binding and function at serotonin 5-HT2C G protein-coupled receptors: receptor homology modelling, ligand docking, and molecular dynamics results validated by experimental studies

    Science.gov (United States)

    Córdova-Sintjago, Tania; Villa, Nancy; Fang, Lijuan; Booth, Raymond G.

    2014-02-01

    The serotonin (5-hydroxytryptamine, 5-HT) 5-HT2 G protein-coupled receptor (GPCR) family consists of types 2A, 2B, and 2C that share ∼75% transmembrane (TM) sequence identity. Agonists for 5-HT2C receptors are under development for psychoses; whereas, at 5-HT2A receptors, antipsychotic effects are associated with antagonists - in fact, 5-HT2A agonists can cause hallucinations and 5-HT2B agonists cause cardiotoxicity. It is known that 5-HT2A TM6 residues W6.48, F6.51, and F6.52 impact ligand binding and function; however, ligand interactions with these residues at the 5-HT2C receptor have not been reported. To predict and validate molecular determinants for 5-HT2C-specific activation, results from receptor homology modelling, ligand docking, and molecular dynamics simulation studies were compared with experimental results for ligand binding and function at wild type and W6.48A, F6.51A, and F6.52A point-mutated 5-HT2C receptors.

  5. Prospects of experimentally reachable beyond Standard Model ...

    Indian Academy of Sciences (India)

    2016-01-06

    Jan 6, 2016 ... Home; Journals; Pramana – Journal of Physics; Volume 86; Issue 2. Prospects of experimentally reachable beyond Standard Model physics in inverse see-saw motivated SO(10) GUT. Ram Lal Awasthi. Special: Supersymmetric Unified Theories and Higgs Physics Volume 86 Issue 2 February 2016 pp 223- ...

  6. Optimal Experimental Design for Model Discrimination

    Science.gov (United States)

    Myung, Jay I.; Pitt, Mark A.

    2009-01-01

    Models of a psychological process can be difficult to discriminate experimentally because it is not easy to determine the values of the critical design variables (e.g., presentation schedule, stimulus structure) that will be most informative in differentiating them. Recent developments in sampling-based search methods in statistics make it…

  7. Experimental results of astrophysical collisionless shock experiments from NIF

    Science.gov (United States)

    Park, Hye-Sook; Higginson, D.; Huntington, C.; Pollock, B.; Remington, B.; Rinderknecht, H.; Ross, J.; Ryutov, D.; Swadling, G.; Wilks, S.; Fiuza, F.; Sakawa, Y.; Spitkovsky, A.; Petrasso, R.; Li, C.; Zylstra, A.; Lamb, D.; Tzeferacos, P.; Gregori, G.; Meinecke, J.; Manuel, M.

    2017-10-01

    We discuss our laboratory experiments using the Omega and NIF lasers to investigate the dynamics of high Mach number collisionless shock formation in two interpenetrating plasma streams. It is believed that in astrophysical environments such shocks are the sites where seed magnetic fields are generated on a cosmologically fast timescale via the Weibel instability. Particle-in-cell (PIC) numerical simulations generate magnetic fields whose magnitude and scale are consistent with this concept. We will present recent experimental results as well as simulations and theoretical interpretations of these observations. The NIF experiments were able to observe the counter-streaming flow interactions through the transition from collisional to collisionless regimes. The latest proton radiography results will be presented. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  8. The VEGA PLASMAG-1 experiment: description and first experimental results

    International Nuclear Information System (INIS)

    Gringauz, K.; Klimenko, I.; Remizov, A.

    1986-02-01

    The PLASMAG-1 experiment on board the identical VEGA-1 and VEGA-2 space probes is described. The probes were launched to comet Halley with Venus flyby. The PLASMAG instruments were designed to explore the solar wind and the cometary plasma environment. This paper describes the main parts and sensors of PLASMAGs and their operating parameters. First experimental results are presented from the interplanetary space. From 1-6 April 1985, the probes crossed a high speed plasma stream of solar wind. The data observed are presented and some preliminary results of evaluation are given. The data are compared with the observations of the ICE space probe wich encountered the Giacobini-Zinner comet. (D.Gy.)

  9. Ion thruster modeling: Particle simulations and experimental validations

    International Nuclear Information System (INIS)

    Wang, Joseph; Polk, James; Brinza, David

    2003-01-01

    This paper presents results from ion thruster modeling studies performed in support of NASA's Deep Space 1 mission and NSTAR project. Fully 3-dimensional computer particle simulation models are presented for ion optics plasma flow and ion thruster plume. Ion optics simulation results are compared with measurements obtained from ground tests of the NSTAR ion thruster. Plume simulation results are compared with in-flight measurements from the Deep Space 1 spacecraft. Both models show excellent agreement with experimental data

  10. Experimental models for Murray’s law

    Science.gov (United States)

    Akita, Dai; Kunita, Itsuki; Fricker, Mark D.; Kuroda, Shigeru; Sato, Katsuhiko; Nakagaki, Toshiyuki

    2017-01-01

    Transport networks are ubiquitous in multicellular organisms and include leaf veins, fungal mycelia and blood vessels. While transport of materials and signals through the network plays a crucial role in maintaining the living system, the transport capacity of the network can best be understood in terms of hydrodynamics. We report here that plasmodium from the large, single-celled amoeboid Physarum was able to construct a hydrodynamically optimized vein-network when evacuating biomass from confined arenas of various shapes through a narrow exit. Increasingly thick veins developed towards the exit, and the network spanned the arena via repetitive bifurcations to give a branching tree. The Hausdorff distance from all parts of the plasmodium to the vein network was kept low, whilst the hydrodynamic conductivity from distal parts of the network to the exit was equivalent, irrespective of the arena shape. This combination of spatial patterning and differential vein thickening served to evacuate biomass at an equivalent rate across the entire arena. The scaling relationship at the vein branches was determined experimentally to be 2.53-3.29, consistent with predictions from Murray’s law. Furthermore, we show that mathematical models for self-organised, adaptive transport in Physarum simulate the experimental network organisation well if the scaling coefficient of the current-reinforcement rule is set to 3. In simulations, this resulted in rapid development of an optimal network that minimised the combined volume and frictional energy in comparison with other scaling coefficients. This would predict that the boundary shear forces within each vein are constant throughout the network, and would be consistent with a feedback mechanism based on a sensing a threshold shear at the vein wall.

  11. 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

  12. VEMAP 1: Selected Model Results

    Data.gov (United States)

    National Aeronautics and Space Administration — The Vegetation/Ecosystem Modeling and Analysis Project (VEMAP) was a multi-institutional, international effort addressing the response of biogeography and...

  13. Multiphysics modelling and experimental validation of high concentration photovoltaic modules

    International Nuclear Information System (INIS)

    Theristis, Marios; Fernández, Eduardo F.; Sumner, Mike; O'Donovan, Tadhg S.

    2017-01-01

    Highlights: • A multiphysics modelling approach for concentrating photovoltaics was developed. • An experimental campaign was conducted to validate the models. • The experimental results were in good agreement with the models. • The multiphysics modelling allows the concentrator’s optimisation. - Abstract: High concentration photovoltaics, equipped with high efficiency multijunction solar cells, have great potential in achieving cost-effective and clean electricity generation at utility scale. Such systems are more complex compared to conventional photovoltaics because of the multiphysics effect that is present. Modelling the power output of such systems is therefore crucial for their further market penetration. Following this line, a multiphysics modelling procedure for high concentration photovoltaics is presented in this work. It combines an open source spectral model, a single diode electrical model and a three-dimensional finite element thermal model. In order to validate the models and the multiphysics modelling procedure against actual data, an outdoor experimental campaign was conducted in Albuquerque, New Mexico using a high concentration photovoltaic monomodule that is thoroughly described in terms of its geometry and materials. The experimental results were in good agreement (within 2.7%) with the predicted maximum power point. This multiphysics approach is relatively more complex when compared to empirical models, but besides the overall performance prediction it can also provide better understanding of the physics involved in the conversion of solar irradiance into electricity. It can therefore be used for the design and optimisation of high concentration photovoltaic modules.

  14. 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

  15. 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.

  16. [Review of experimental models: sinusitis in rabbits].

    Science.gov (United States)

    Perez, André Coura; Buzatto, Guilherme Pietrucci; Dantas, Ivan de Picole; Dorgam, João Vicente; Valera, Fabiana Cardoso Pereira; Tamashiro, Edwin; Lima, Wilma Terezinha Anselmo

    2014-01-01

    In order to better understand the pathophysiology of rhinosinusitis, several attempts have been made to create the disease in an animal model. Among the studied rodents each has its advantages and disadvantages. Rabbits are considered more appropriate for studies that require surgical manipulation or invasive procedures. To evaluate the most viable experimental model of rhinosinusitis in rabbits to be adopted in future studies. An electronic search for studies with experimental models of rhinosinusitis in rabbits published in English and Portuguese between July of 1967 and January of 2013 was conducted in Medline, Pub Med, Cochrane, and CAPES databases, using the keywords "sinusitis", "rabbits", and "polyps". A total of 256 studies were retrieved, but in accordance with the inclusion and exclusion criteria, only ten studies were selected. Many different methods of response assessment were used in these studies. To date, there is no ideal experimental model for induction of acute or chronic rhinosinusitis in rabbits, but the rhinogenic model appears to be the most viable option for the continuity of studies of the disease. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  17. 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)

  18. Irradiation Design for an Experimental Murine Model

    International Nuclear Information System (INIS)

    Ballesteros-Zebadua, P.; Moreno-Jimenez, S.; Suarez-Campos, J. E.; Celis, M. A.; Larraga-Gutierrez, J. M.; Garcia-Garduno, O. A.; Rubio-Osornio, M. C.; Custodio-Ramirez, V.; Paz, C.

    2010-01-01

    In radiotherapy and stereotactic radiosurgery, small animal experimental models are frequently used, since there are still a lot of unsolved questions about the biological and biochemical effects of ionizing radiation. This work presents a method for small-animal brain radiotherapy compatible with a dedicated 6MV Linac. This rodent model is focused on the research of the inflammatory effects produced by ionizing radiation in the brain. In this work comparisons between Pencil Beam and Monte Carlo techniques, were used in order to evaluate accuracy of the calculated dose using a commercial planning system. Challenges in this murine model are discussed.

  19. Experimental results on electron beam combination and bunch frequency multiplication

    Directory of Open Access Journals (Sweden)

    Roberto Corsini

    2004-04-01

    Full Text Available The aim of the CLIC Test Facility CTF3 at CERN is to demonstrate the feasibility of the key points of the two-beam acceleration based compact linear collider study. In particular, it addresses the efficient generation of a drive beam with the appropriate time structure of the electron bunches in order to produce high power rf pulses at a frequency of 30 GHz. This time structure requires a high bunch repetition frequency. It is obtained by successive injections of bunch trains into an isochronous ring using transversely deflecting rf structures. The major goal of the now completed first phase of the CTF3 was to achieve the bunch train combination at low charge. In this paper, we give a description of the project and summarize the experimental results, with a focus on the successful bunch frequency multiplication for various factors up to 5.

  20. Self-organization scenario grounded on new experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Lozneanu, E. [Complex System Laboratory, Al. I. Cuza University, Blvd Carol I, No. 11, Iasi 700506 (Romania); Sanduloviciu, M. [Complex System Laboratory, Al. I. Cuza University, Blvd Carol I, No. 11, Iasi 700506 (Romania)], E-mail: msandu@uaic.ro

    2009-05-30

    Recently published experimental results proving that well-located plasma created in air by quick injection of energy naturally evolves into a coherent, apparently stable and luminous gaseous body, dubbed fireball, are explained considering a new scenario of self-organization. Bordered by a functional double layer emerged by direct conversion of thermal energy into electric field energy through a mechanism exploiting collective effects of quantum processes, the fireball survives for durations that depend on the environmental conditions. Based on this scenario of self-organization that evolves in a time span in which the second law of thermodynamics ceases to work, enigmas as the ball lightning and the origin of life becomes potentially explainable.

  1. Experimental Results of Rover-Based Coring and Caching

    Science.gov (United States)

    Backes, Paul G.; Younse, Paulo; DiCicco, Matthew; Hudson, Nicolas; Collins, Curtis; Allwood, Abigail; Paolini, Robert; Male, Cason; Ma, Jeremy; Steele, Andrew; hide

    2011-01-01

    Experimental results are presented for experiments performed using a prototype rover-based sample coring and caching system. The system consists of a rotary percussive coring tool on a five degree-of-freedom manipulator arm mounted on a FIDO-class rover and a sample caching subsystem mounted on the rover. Coring and caching experiments were performed in a laboratory setting and in a field test at Mono Lake, California. Rock abrasion experiments using an abrading bit on the coring tool were also performed. The experiments indicate that the sample acquisition and caching architecture is viable for use in a 2018 timeframe Mars caching mission and that rock abrasion using an abrading bit may be feasible in place of a dedicated rock abrasion tool.

  2. VEMAP 1: Selected Model Results

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The Vegetation/Ecosystem Modeling and Analysis Project (VEMAP) was a multi-institutional, international effort addressing the response of biogeography and...

  3. Delaminations in composite plates under transverse impact loads - Experimental results

    Science.gov (United States)

    Finn, Scott R.; He, Ye-Fei; Springer, George S.

    1993-01-01

    Tests were performed measuring the locations and geometries of delaminations in Fiberite T300/976 graphite/epoxy, Fiberite IM7/977-2 graphite-toughened epoxy, and ICI APC-2 graphite/PEEK plates subjected to transverse impact loads. The data provide specific information on the effects of impactor velocity, impactor mass, material, thickness of back ply group, difference in fiber orientation between adjacent ply groups, plate thickness, and impactor nose radius. The data were compared to the results of the Finn-Springer model. The model was found to describe the data with reasonable accuracy.

  4. Construction of a WMR for Trajectory Tracking Control: Experimental Results

    Directory of Open Access Journals (Sweden)

    R. Silva-Ortigoza

    2013-01-01

    Full Text Available This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x*,y* and orientation (φ*. Then, a low-level control law, based on a proportional integral (PI approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1 time-varying parametric trajectories such as straight lines and parabolas and (2 smooth curves fitted by cubic splines which are generated by the desired data points x1*,y1*,…,xn*,yn*. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software.

  5. Construction of a WMR for trajectory tracking control: experimental results.

    Science.gov (United States)

    Silva-Ortigoza, R; Márquez-Sánchez, C; Marcelino-Aranda, M; Marciano-Melchor, M; Silva-Ortigoza, G; Bautista-Quintero, R; Ramos-Silvestre, E R; Rivera-Díaz, J C; Muñoz-Carrillo, D

    2013-01-01

    This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x₁∗, y₁∗),..., (x(n)∗, y(n)∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software.

  6. Modeling of Cracked Beams by the Experimental Design Method

    Directory of Open Access Journals (Sweden)

    M. Serier

    Full Text Available Abstract The understanding of phenomena, no matter their nature is based on the experimental results found. In the most cases, this requires an important number of tests in order to put a reliable and useful observation served into solving the technical problems subsequently. This paper is based on independent and variables combination resulting from experimentation in a mathematical formulation. Indeed, mathematical modeling gives us the advantage to optimize and predict the right choices without passing each case by the experiment. In this work we plan to apply the experimental design method on the experimental results found by (Deokar, A, 2011, concerning the effect of the size and position of a crack on the measured frequency of a beam console, and validating the mathematical model to predict other frequencies

  7. Ischemic postconditioning: experimental models and protocol algorithms.

    Science.gov (United States)

    Skyschally, Andreas; van Caster, Patrick; Iliodromitis, Efstathios K; Schulz, Rainer; Kremastinos, Dimitrios T; Heusch, Gerd

    2009-09-01

    Ischemic postconditioning, a simple mechanical maneuver at the onset of reperfusion, reduces infarct size after ischemia/reperfusion. After its first description in 2003 by Zhao et al. numerous experimental studies have investigated this protective phenomenon. Whereas the underlying mechanisms and signal transduction are not yet understood in detail, infarct size reduction by ischemic postconditioning was confirmed in all species tested so far, including man. We have now reviewed the literature with focus on experimental models and protocols to better understand the determinants of protection by ischemic postconditioning or lack of it. Only studies with infarct size as unequivocal endpoint were considered. In all species and models, the duration of index ischemia and the protective protocol algorithm impact on the outcome of ischemic postconditioning, and gender, age, and myocardial temperature contribute.

  8. Delaminations in composite plates under transverse static loads - Experimental results

    Science.gov (United States)

    Finn, Scott R.; He, Yi-Fei; Springer, George S.

    1992-01-01

    Tests were performed measuring the damage initiation loads and the locations, shapes, and sizes of delaminations in Fiberite T300/976 graphite/epoxy, Fiberite IM7/977-2 graphite-toughened epoxy, and ICI APC-2 graphite-PEEK plates subjected to transverse static loads. The data were compared to the results of the Finn-Springer model, and good agreements were found between the measured and calculated delamination lengths and widths.

  9. New experimental model for training in videosurgery Novo modelo experimental para treinamento em videocirurgia

    Directory of Open Access Journals (Sweden)

    Danilo Malta Batista

    2012-10-01

    Full Text Available PURPOSE: To develop a new experimental model of lower cost for training in videosurgery. METHODS: This project was performed at the Nucleus of Experimental Surgery of the Bahiana School of Medicine and Public Health, based on previous models described in the literature and under the supervision of the full professor of Operative Technique and Experimental Surgery II. It was made a model cube-shaped, made of wood, with holes distributed in various locations, rubber stoppers for the holes and lined externally with carpet, and internally with laminate. RESULTS: The new experimental model is of low cost and reproduces quite faithfully several videosurgical procedures. CONCLUSION: Medical schools interested in the subject may adopt the new model for training in videosurgery without the need of high costs for making and using these models.OBJETIVO: Desenvolver um novo modelo experimental de baixo custo para treinamento em videocirurgia MÉTODOS: Este projeto foi conduzido no Núcleo de Cirurgia Experimental da Escola Bahiana de Medicina e Saúde Pública, baseado em modelos prévios descritos na literatura e sob a supervisão do professor titular de Técnica Operatória e Cirurgia Experimental II. Foi feito um modelo em formato de cubo, de madeira, com furos distribuídos em vários locais, tampas de borracha para os orifícios e forrado externamente com carpete e internamente com laminado. RESULTADOS: O novo modelo experimental desenvolvido é de baixo custo e reproduz de forma bastante fiel diversos procedimentos videocirúrgicos. CONCLUSÃO: Faculdades médicas interessadas no tema poderão adotar o novo modelo para o treinamento em videocirurgia sem que sejam necessários gastos elevados para a confecção e o uso desses modelos.

  10. Experimental results of chemical recording using thermally sensitive liposomes

    Science.gov (United States)

    Tanner, Maria E.; Vasievich, Elizabeth A.; Protz, Jonathan M.

    2008-04-01

    A new generation of inertial measurement technology is being developed enabling a 10-micron particle to be "aware" of its geospatial location and respond to this information. The proposed approach combines an inertially-sensitive nano-structure or nano fluid/structure system with a nano-sized chemical reactor that functions as an analog computer. By using chemistry to perform the necessary computational steps in our device, it is possible to overcome traditional limitations on device size. The proposed nanodevice utilizes mechanical sensing and chemical recording to record the time history of various state variables. Using a micro-track containing regions of different temperatures and thermally-sensitive liposomes (TSL), a range of accelerations can be recorded and the position determined. Through careful design, TSL can be developed that have unique transition temperatures and each class of TSL will contain a unique DNA sequence that serves as an identifier. Acceleration can be detected through buoyancy-driven convection. As the liposomes travel to regions of warmer temperature, they will release their contents at the recording site, thus documenting the acceleration. This paper will present the initial proof-of-concept experimental results achieved from chemical recording of the state variable temperature. The experiment focuses on the liposome release of the DNA due to temperature variations and subsequent binding and recording of the time history. These results prove the feasibility of this method of sensing and recording of the history of state variables.

  11. FRVT 2006 and ICE 2006 large-scale experimental results.

    Science.gov (United States)

    Phillips, P Jonathon; Scruggs, W Todd; O'Toole, Alice J; Flynn, Patrick J; Bowyer, Kevin W; Schott, Cathy L; Sharpe, Matthew

    2010-05-01

    This paper describes the large-scale experimental results from the Face Recognition Vendor Test (FRVT) 2006 and the Iris Challenge Evaluation (ICE) 2006. The FRVT 2006 looked at recognition from high-resolution still frontal face images and 3D face images, and measured performance for still frontal face images taken under controlled and uncontrolled illumination. The ICE 2006 evaluation reported verification performance for both left and right irises. The images in the ICE 2006 intentionally represent a broader range of quality than the ICE 2006 sensor would normally acquire. This includes images that did not pass the quality control software embedded in the sensor. The FRVT 2006 results from controlled still and 3D images document at least an order-of-magnitude improvement in recognition performance over the FRVT 2002. The FRVT 2006 and the ICE 2006 compared recognition performance from high-resolution still frontal face images, 3D face images, and the single-iris images. On the FRVT 2006 and the ICE 2006 data sets, recognition performance was comparable for high-resolution frontal face, 3D face, and the iris images. In an experiment comparing human and algorithms on matching face identity across changes in illumination on frontal face images, the best performing algorithms were more accurate than humans on unfamiliar faces.

  12. Seclazone Reactor Modeling And Experimental Validation

    Energy Technology Data Exchange (ETDEWEB)

    Osinga, T. [ETH-Zuerich (Switzerland); Olalde, G. [CNRS Odeillo (France); Steinfeld, A. [PSI and ETHZ (Switzerland)

    2005-03-01

    A numerical model is formulated for the SOLZINC solar chemical reactor for the production of Zn by carbothermal reduction of ZnO. The model involves solving, by the finite-volume technique, a 1D unsteady state energy equation that couples heat transfer to the chemical kinetics for a shrinking packed bed exposed to thermal radiation. Validation is accomplished by comparison with experimentally measured temperature profiles and Zn production rates as a function of time, obtained for a 5-kW solar reactor tested at PSI's solar furnace. (author)

  13. Experimental In Vivo Models of Candidiasis

    Directory of Open Access Journals (Sweden)

    Esther Segal

    2018-02-01

    Full Text Available Candidiasis is a multifaceted fungal disease including mucosal-cutaneous, visceral, and disseminated infections caused by yeast species of the genus Candida. Candida infections are among the most common human mycoses. Candida species are the third to fourth most common isolates from bloodstream infections in neutropenic or immunocompromised hospitalized patients. The mucosal-cutaneous forms—particularly vaginal infections—have a high prevalence. Vaginitis caused by Candida species is the second most common vaginal infection. Hence, candidiasis is a major subject for research, including experimental in vivo models to study pathogenesis, prevention, or therapy of the disease. The following review article will focus on various experimental in vivo models in different laboratory animals, such as mammals (mice, rats, rabbits, the fruit fly–Drosophila melanogaster, the larvae of the moth Galleria mellonella, or the free-living nematode Caenorhabditis elegans. The review will describe the induction of the different clinical forms of candidiasis in the various models and the validity of such models in mimicking the human clinical situations. The use of such models for the assessment of antifungal drugs, evaluation of potential vaccines to protect before candidiasis, exploration of Candida virulence factors, and comparison of pathogenicity of different Candida species will be included in the review. All of the above will be reported as based on published studies of numerous investigators as well as on the research of the author and his group.

  14. 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.

  15. Experimental results on recent applications of shot peening

    International Nuclear Information System (INIS)

    Zaid, A.I.O.

    2001-01-01

    Shot peening is a mechanical surface treatment by which the surface of an elastic plastic component is subjected to multiple impact of high speed hard spheres, hence introducing a compressive stress layer of certain depth below the surface. This compressive stress layer results in enhancement of the fatigue life of the component. In this paper, the mechanism of shot peening and the effect of the parameters related to it are reviewed and discussed. The effect of shot peening on the fatigue life of aluminum alloy 7075-T6 and the phenomenological aspects associated with it are also given and discussed. Also, the effect of shot peening on aluminum alloy 2024-T3 in the as received and peened conditions is presented and discussed. Butt single U and butt double vee joints were both investigated from which it was found that the butt single U joint possessed higher values of fatigue life than the double vee joint for the same shot peening intensity. Finally, experimental results on a recent application that is the effect of shot peening on the fatigue life of stainless steel 17-4PH prior to hard chromium plating are given and discussed. Comparison is also made among these results and those obtained in the case of the chromium plated without peening and as received conditions. It was found that shot peening caused an increase of 667% in the fatigue life of stainless steel 17-4PH at 0.57 Y stress level, whereas hard chromium plating was found to reduce its fatigue life and strength. Hence, chromium plating after shot peening is recommended. (author)

  16. Experimental result of poloidal limiter baking of Aditya tokamak

    International Nuclear Information System (INIS)

    Jadeja, K.A.; Arambhadiya, B.G.; Bhatt, S.B.; Bora, D.

    2005-01-01

    In tokamak Aditya, Poloidal limiter function as the operational limiter and are subjected to very high particles load and heat flux during plasma discharge. In addition, Poloidal limiter is the first material surface to come in contact with the hot plasma. In plasma discharge, the impurity generations from limiter are mostly by adsorbed particles. The baking of limiter provides high degassing rate and thermal desorption of adsorbed particles of limiter to reduce impurities from the limiter tiles. The series of experiments are done with different conditions like, Baking of limiter SS ring by heating element with and without limiter tiles in atmosphere and vacuum. Than Poloidal limiter is structured with 14 numbers of graphite tiles and electrical isolated to the vessel and support structure. As a heating element and for electrical isolation, Nychrome wire and ceramic block with ceramic tubes are used. In addition, Thermo couple and two DC power supply (0-10 Ampere) are used for limiter baking. Mass analyzer gives partial pressures of different species to observe effect of limiter baking. For the period of Poloidal limiter baking in Aditya, the partial pressures of different species like hydrogen, water vapor, and oxygen are extremely increased with time duration. This paper presents series of experimental results of poloidal limiter baking. (author)

  17. First experimental results with a new waterjet dissector: Erbejet 2.

    Science.gov (United States)

    Tschan, C A; Tschan, K; Krauss, J K; Oertel, J

    2009-11-01

    Waterjet dissection represents a useful technique for many surgical procedures. In this experimental study, the technical features and dissection qualities of the new Erbejet 2 with its new pump and nozzle applicator system are evaluated for its neurosurgical use compared to the established Helix Hydro-Jet. One hundred twenty-six fresh cadaveric pig brains were simultaneously cut with the Helix Hydro-Jet and Erbejet 2. Different pressure levels were applied to cerebral tissue with and without meninges, cerebellum and brainstem. Additionally, dissection characteristics of various cutting media were investigated. There was a nearly equal dissection quality at up to 10 bar of both instruments. In contrast to the Helix Hydro-Jet, Erbejet 2 application at higher pressures resulted in an almost linear increase of dissection depth with a small standard deviation. Smoother cutting margins and less foaming were found. Preserved vessels were observed with both devices. Hydroxyaethyl starch led, in contrast to Ringer's solution and isotonic saline solution, to increased dissection width and more foaming. The new Erbejet 2 is more precise, with almost linear correlation of pressure and dissection depth compared to the Helix Hydro-Jet. Less foaming and the possible application of various separating media are a considerable advantage. All things considered, the new Erbejet 2 offers more options to enlarge the field of neurosurgical indications for waterjet dissection.

  18. Models for Experimental High Density Housing

    Science.gov (United States)

    Bradecki, Tomasz; Swoboda, Julia; Nowak, Katarzyna; Dziechciarz, Klaudia

    2017-10-01

    The article presents the effects of research on models of high density housing. The authors present urban projects for experimental high density housing estates. The design was based on research performed on 38 examples of similar housing in Poland that have been built after 2003. Some of the case studies show extreme density and that inspired the researchers to test individual virtual solutions that would answer the question: How far can we push the limits? The experimental housing projects show strengths and weaknesses of design driven only by such indexes as FAR (floor attenuation ratio - housing density) and DPH (dwellings per hectare). Although such projects are implemented, the authors believe that there are reasons for limits since high index values may be in contradiction to the optimum character of housing environment. Virtual models on virtual plots presented by the authors were oriented toward maximising the DPH index and DAI (dwellings area index) which is very often the main driver for developers. The authors also raise the question of sustainability of such solutions. The research was carried out in the URBAN model research group (Gliwice, Poland) that consists of academic researchers and architecture students. The models reflect architectural and urban regulations that are valid in Poland. Conclusions might be helpful for urban planners, urban designers, developers, architects and architecture students.

  19. Experimental animal modelling for TB vaccine development

    Directory of Open Access Journals (Sweden)

    Pere-Joan Cardona

    2017-03-01

    Full Text Available Research for a novel vaccine to prevent tuberculosis is an urgent medical need. The current vaccine, BCG, has demonstrated a non-homogenous efficacy in humans, but still is the gold standard to be improved upon. In general, the main indicator for testing the potency of new candidates in animal models is the reduction of the bacillary load in the lungs at the acute phase of the infection. Usually, this reduction is similar to that induced by BCG, although in some cases a weak but significant improvement can be detected, but none of candidates are able to prevent establishment of infection. The main characteristics of several laboratory animals are reviewed, reflecting that none are able to simulate the whole characteristics of human tuberculosis. As, so far, no surrogate of protection has been found, it is important to test new candidates in several models in order to generate convincing evidence of efficacy that might be better than that of BCG in humans. It is also important to investigate the use of “in silico” and “ex vivo” models to better understand experimental data and also to try to replace, or at least reduce and refine experimental models in animals.

  20. Numerical Modeling and Experimental Testing of a Wave Energy Converter

    DEFF Research Database (Denmark)

    Zurkinden, Andrew Stephen; Kramer, Morten; Ferri, Francesco

    numerical values for comparison with the experimental test results which were carried out in the same time. It is for this reason why Chapter 4 does consist exclusively of numerical values. Experimental values and measured time series of wave elevations have been used throughout the report in order to a......) validate the numerical model and b) preform stochastic analysis. The latter technique is introduced in order to optimize the control parameters of the power take off system....

  1. 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

  2. Experimental model of arteriovenous fistula in pigs

    International Nuclear Information System (INIS)

    Suh, Dae Chul; Seo, Dong Man; Kim, Hyun Jin and others

    1997-01-01

    To establish an experimental model of arteriovenous fistula in pigs. Ten fistulas were created in eight pigs, and angiography was performed 3 to 5 days after surgery. A follow-up angiogram of three fistulas was obtained 2 to 12 weeks later. In one animal, pathologic examination showed occlusion 8 weeks after a successful operations. Eight angiograms of nine fistulas in seven pigs were obtained; one animal died due to cardiac failure. In six pigs, high-flow fistulas were shown to be present, and in two, the fistulas were slow flow; a pseudoaneurysm was seen in one. A follow-up angiogram obtained in three cases showed occlusion of the fistula. Pathologic examination of one animal showed fibrosis in the occluded portion of the fistula. An arteriovenous fistula model was surgically established in 80% of cases; during follow-up, three fistulas were seen to be occluded due to fibrosis. This model can therefore be used within one week of surgery

  3. Investigation of wax precipitation in crude oil: Experimental and modeling

    Directory of Open Access Journals (Sweden)

    Taraneh Jafari Behbahani

    2015-09-01

    Full Text Available In this work, a series of experiments were carried to investigation of rheological behavior of crude oil using waxy crude oil sample in the absence/presence of flow improver such as ethylene-vinyl acetate copolymer. The rheological data covered the temperature range of 5–30 °C. The results indicated that the performance of flow improver was dependent on its molecular weight. Addition of small quantities of flow improver, can improve viscosity and pour point of crude oil. Also, an Artificial Neural Network (ANN model using Multi-Layer Perceptron (MLP topology has been developed to account wax appearance temperature and the amount of precipitated wax and the model was verified using experimental data given in this work and reported in the literature. In order to compare the performance of the proposed model based on Artificial Neural Network, the wax precipitation experimental data at different temperatures were predicted using solid solution model and multi-solid phase model. The results showed that the developed model based on Artificial Neural Network can predict more accurately the wax precipitation experimental data in comparison to the previous models such as solid solution and multi-solid phase model with AADs less than 0.5%. Furthermore, the number of parameters required for the Artificial Neural Network (ANN model is less than the studied thermodynamic models.

  4. Superficial tension: experimental model with simple materials

    Directory of Open Access Journals (Sweden)

    Tintori Ferreira, María Alejandra

    2012-09-01

    Full Text Available In this work appears a didactic offer based on an experimental activity using materials of very low cost, orientated to achieving that the student understand and interpret the phenomenon of superficial tension together with the importance of the modeling in sciences. It has as principal aim of education bring the student over to the mechanics of the static fluids and the intermolecular forces, combining scientific contents with questions near to the student what provides an additional motivation to the reflection of the scientific investigation.

  5. Graphical Models for Quasi-Experimental Designs

    Science.gov (United States)

    Kim, Yongnam; Steiner, Peter M.; Hall, Courtney E.; Su, Dan

    2016-01-01

    Experimental and quasi-experimental designs play a central role in estimating cause-effect relationships in education, psychology, and many other fields of the social and behavioral sciences. This paper presents and discusses the causal graphs of experimental and quasi-experimental designs. For quasi-experimental designs the authors demonstrate…

  6. Experimental results from a diagnostic beam line for text

    International Nuclear Information System (INIS)

    Coupland, J.R.; Hammond, D.P.; Mepham, J.W.; Hancock, O.J.

    1987-01-01

    The experimental performance of a high brightness neutral beam system is described. The neutral beam serves as a diagnostic on the Fusion Research Center Tokamak TEXT, to measure impurities by observing optical spectra produced by collisions between the injected neutral beam and ions in the plasma

  7. Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

    Science.gov (United States)

    Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

    2013-01-01

    In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 degC temperature increase from the nominal vapor temperature. The 19 degC temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental

  8. Space Launch System Base Heating Test: Experimental Operations & Results

    Science.gov (United States)

    Dufrene, Aaron; Mehta, Manish; MacLean, Matthew; Seaford, Mark; Holden, Michael

    2016-01-01

    NASA's Space Launch System (SLS) uses four clustered liquid rocket engines along with two solid rocket boosters. The interaction between all six rocket exhaust plumes will produce a complex and severe thermal environment in the base of the vehicle. This work focuses on a recent 2% scale, hot-fire SLS base heating test. These base heating tests are short-duration tests executed with chamber pressures near the full-scale values with gaseous hydrogen/oxygen engines and RSRMV analogous solid propellant motors. The LENS II shock tunnel/Ludwieg tube tunnel was used at or near flight duplicated conditions up to Mach 5. Model development was based on the Space Shuttle base heating tests with several improvements including doubling of the maximum chamber pressures and duplication of freestream conditions. Test methodology and conditions are presented, and base heating results from 76 runs are reported in non-dimensional form. Regions of high heating are identified and comparisons of various configuration and conditions are highlighted. Base pressure and radiometer results are also reported.

  9. 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

  10. Results of experimental investigations to determine external tank protuberance loads using a 0.03-scale model of the Space Shuttle launch configuration (model 47-OTS) in the NASA/ARC unitary plan wind tunnel, volume 1

    Science.gov (United States)

    Houlihan, S. R.

    1992-01-01

    Data were obtained on a 3-percent model of the Space Shuttle launch vehicle in the NASA/Ames Research Center 11x11-foot and 9x7-foot Unitary Plan Wind Tunnels. This test series has been identified as IA190A/B and was conducted from 7 Feb. 1980 to 19 Feb. 1980 (IA190A) and from 17 March 1980 to 19 March 1980 and from 8 May 1980 to 30 May 1980 (IA190B). The primary test objective was to obtain structural loads on the following external tank protuberances: (1) LO2 feedline, (2) GO2 pressure line, (3) LO2 antigeyser line, (4) GH2 pressure line, (5) LH2 tank cable tray, (6) LO2 tank cable tray, (7) Bipod, (8) ET/SRB cable tray, and (9) Crossbeam/Orbiter cable tray. To fulfill these objectives the following steps were taken: (1) Eight 3-component balances were used to measure forces on various sections of 1 thru 6 above. (2) 315 pressure orifices were distributed over all 9 above items. The LO2 feedline was instrumented with 96 pressure taps and was rotated to four positions to yield 384 pressure measurements. The LO2 antigeyser line was instrumented with 64 pressure taps and was rotated to two positions to yield 128 pressure measurements. (3) Three Chrysler miniature flow direction probes were mounted on a traversing mechanism on the tank upper surface centerline to obtain flow field data between the forward and aft attach structures. (4) Schlieren photographs and ultraviolet flow photographs were taken at all test conditions. Data from each of the four test phases are presented.

  11. Results of Experimental Investigations to Determine External Tank Protuberance Loads Using a 0.03-Scale Model of the Space Shuttle Launch Configuration (Model 47-OTS) in the NASA/ARC Unitary Plan Wind Tunnel, Volume 2

    Science.gov (United States)

    Houlihan, S. R.

    1992-01-01

    Data were obtained on a 3-percent model of the Space Shuttle launch vehicle in the NASA/Ames Research Center 11x11-foot and 9x7-foot Unitary Plan Wind Tunnels. This test series has been identified as IA19OA/B and was conducted from 7 Feb. 1980 to 19 Feb. 1980 (IA19OA) and from 17 March 1980 to 19 March 1980 and from 8 May 1980 to 30 May 1980 (IA19OB). The primary test objective was to obtain structural loads on the following external tank protuberances: (1) LO2 feedline; (2) GO2 pressure line; (3) LO2 antigeyser line; (4) GH2 pressure line; (5) LH2 tank cable tray; (6) LO2 tank cable tray; (7) Bipod; (8) ET/SRB cable tray; and (9) Crossbeam/Orbiter cable tray. To fulfill these objectives the following steps were taken: Eight 3-component balances were used to measure forces on various sections of 1 thru 6 above; 315 pressure orifices were distributed over all 9 above items. The LO2 feedline was instrumented with 96 pressure taps and was rotated to four positions to yield 384 pressure measurements. The LO2 antigeyser line was instrumented with 64 pressure taps and was rotated to two positions to yield 128 pressure measurements; Three Chrysler miniature flow direction probes were mounted on a traversing mechanism on the tank upper surface centerline to obtain flow field data between the forward and aft attach structures; and Schlieren photographs and ultraviolet flow photographs were taken at all test conditions. Data from each of the four test phases are presented.

  12. Results of experimental investigations to determine external tank protuberance loads using a 0.03-scale model of the Space Shuttle launch configuration (model 47-OTS) in the NASA/ARC unitary plan wind tunnel, volume 1

    Science.gov (United States)

    Houlihan, S. R.

    1992-02-01

    Data were obtained on a 3-percent model of the Space Shuttle launch vehicle in the NASA/Ames Research Center 11x11-foot and 9x7-foot Unitary Plan Wind Tunnels. This test series has been identified as IA190A/B and was conducted from 7 Feb. 1980 to 19 Feb. 1980 (IA190A) and from 17 March 1980 to 19 March 1980 and from 8 May 1980 to 30 May 1980 (IA190B). The primary test objective was to obtain structural loads on the following external tank protuberances: (1) LO2 feedline, (2) GO2 pressure line, (3) LO2 antigeyser line, (4) GH2 pressure line, (5) LH2 tank cable tray, (6) LO2 tank cable tray, (7) Bipod, (8) ET/SRB cable tray, and (9) Crossbeam/Orbiter cable tray. To fulfill these objectives the following steps were taken: (1) Eight 3-component balances were used to measure forces on various sections of 1 thru 6 above. (2) 315 pressure orifices were distributed over all 9 above items. The LO2 feedline was instrumented with 96 pressure taps and was rotated to four positions to yield 384 pressure measurements. The LO2 antigeyser line was instrumented with 64 pressure taps and was rotated to two positions to yield 128 pressure measurements. (3) Three Chrysler miniature flow direction probes were mounted on a traversing mechanism on the tank upper surface centerline to obtain flow field data between the forward and aft attach structures. (4) Schlieren photographs and ultraviolet flow photographs were taken at all test conditions. Data from each of the four test phases are presented.

  13. Results of experimental investigations to determine external tank protuberance loads using a 0.03-scale model of the Space Shuttle launch configuration (Model 47-OTS) in the NASA/ARC unitary plan wind tunnel, volume 2

    Science.gov (United States)

    Houlihan, S. R.

    1992-02-01

    Data were obtained on a 3-percent model of the Space Shuttle launch vehicle in the NASA/Ames Research Center 11x11-foot and 9x7-foot Unitary Plan Wind Tunnels. This test series has been identified as IA19OA/B and was conducted from 7 Feb. 1980 to 19 Feb. 1980 (IA19OA) and from 17 March 1980 to 19 March 1980 and from 8 May 1980 to 30 May 1980 (IA19OB). The primary test objective was to obtain structural loads on the following external tank protuberances: (1) LO2 feedline; (2) GO2 pressure line; (3) LO2 antigeyser line; (4) GH2 pressure line; (5) LH2 tank cable tray; (6) LO2 tank cable tray; (7) Bipod; (8) ET/SRB cable tray; and (9) Crossbeam/Orbiter cable tray. To fulfill these objectives the following steps were taken: Eight 3-component balances were used to measure forces on various sections of 1 thru 6 above; 315 pressure orifices were distributed over all 9 above items. The LO2 feedline was instrumented with 96 pressure taps and was rotated to four positions to yield 384 pressure measurements. The LO2 antigeyser line was instrumented with 64 pressure taps and was rotated to two positions to yield 128 pressure measurements; Three Chrysler miniature flow direction probes were mounted on a traversing mechanism on the tank upper surface centerline to obtain flow field data between the forward and aft attach structures; and Schlieren photographs and ultraviolet flow photographs were taken at all test conditions. Data from each of the four test phases are presented.

  14. Rheological study of an hydrate slurry as secondary two-phase refrigerant. Experimental results and modelling; Etude rheologique d'une suspension d'hydrates en tant que fluide frigoporteur diphasique: resultats experimentaux et modelisation

    Energy Technology Data Exchange (ETDEWEB)

    Darbouret, M.

    2005-12-15

    Secondary two-phase fluids are suspensions of solid crystals. Thanks to the melting latent heat, they present a great interest for cold transportation. Moreover, they are a mean of reducing the amount of classical refrigerant. In the refrigeration field, ice slurries are already used. The goal is now to extend this technology to other temperature ranges suitable for other applications like freezing or air-conditioning. For an air-conditioning application, a TBAB (Tetra-Butyl-Ammonium Bromide) aqueous solution is studied. Under atmospheric pressure and for positive temperatures, this solution crystallizes into ice-like compounds named 'hydrates'. First, the physical properties of the aqueous solution and its crystallisation conditions were studied. Two different types of hydrates can appear. The goal of the experimental set-up is to study the rheological behaviour of two-phase fluids. Slurries are made in brushed-surface heat exchanger and pumped into pipes where flow rates and pressure drops are measured. The rheological behaviour of TBAB hydrates slurries can be described using a Bingham fluid model. We highlight that the two rheological parameters, which are the apparent viscosity and the yield shear stress, depend on the volume fraction of crystal of course, but also on the hydrate type, and on the initial concentration of the solution. The yield shear stress is interpreted as the consequence of the Van der Waals inter-particle interaction forces. Finally, possible stratification effects are modelled with a finite difference method. The principle is to calculate particle concentration and velocity profiles following the flow of the slurry. Calculations are validated with experimental velocity profiles published by P. Reghem (2002). This model underlines the influence of the particle distribution in the pipe on pressure drops. (author)

  15. Development of a fault test experimental facility model using Matlab

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Iraci Martinez; Moraes, Davi Almeida, E-mail: martinez@ipen.br, E-mail: dmoraes@dk8.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The Fault Test Experimental Facility was developed to simulate a PWR nuclear power plant and is instrumented with temperature, level and pressure sensors. The Fault Test Experimental Facility can be operated to generate normal and fault data, and these failures can be added initially small, and their magnitude being increasing gradually. This work presents the Fault Test Experimental Facility model developed using the Matlab GUIDE (Graphical User Interface Development Environment) toolbox that consists of a set of functions designed to create interfaces in an easy and fast way. The system model is based on the mass and energy inventory balance equations. Physical as well as operational aspects are taken into consideration. The interface layout looks like a process flowchart and the user can set the input variables. Besides the normal operation conditions, there is the possibility to choose a faulty variable from a list. The program also allows the user to set the noise level for the input variables. Using the model, data were generated for different operational conditions, both under normal and fault conditions with different noise levels added to the input variables. Data generated by the model will be compared with Fault Test Experimental Facility data. The Fault Test Experimental Facility theoretical model results will be used for the development of a Monitoring and Fault Detection System. (author)

  16. Development of a fault test experimental facility model using Matlab

    International Nuclear Information System (INIS)

    Pereira, Iraci Martinez; Moraes, Davi Almeida

    2015-01-01

    The Fault Test Experimental Facility was developed to simulate a PWR nuclear power plant and is instrumented with temperature, level and pressure sensors. The Fault Test Experimental Facility can be operated to generate normal and fault data, and these failures can be added initially small, and their magnitude being increasing gradually. This work presents the Fault Test Experimental Facility model developed using the Matlab GUIDE (Graphical User Interface Development Environment) toolbox that consists of a set of functions designed to create interfaces in an easy and fast way. The system model is based on the mass and energy inventory balance equations. Physical as well as operational aspects are taken into consideration. The interface layout looks like a process flowchart and the user can set the input variables. Besides the normal operation conditions, there is the possibility to choose a faulty variable from a list. The program also allows the user to set the noise level for the input variables. Using the model, data were generated for different operational conditions, both under normal and fault conditions with different noise levels added to the input variables. Data generated by the model will be compared with Fault Test Experimental Facility data. The Fault Test Experimental Facility theoretical model results will be used for the development of a Monitoring and Fault Detection System. (author)

  17. Linking Experimental Characterization and Computational Modeling in Microstructural Evolution

    Energy Technology Data Exchange (ETDEWEB)

    Demirel, Melik Cumhar [Univ. of Pittsburgh, PA (United States)

    2002-06-01

    It is known that by controlling microstructural development, desirable properties of materials can be achieved. The main objective of our research is to understand and control interface dominated material properties, and finally, to verify experimental results with computer simulations. In order to accomplish this objective, we studied the grain growth in detail with experimental techniques and computational simulations. We obtained 5170-grain data from an Aluminum-film (120μm thick) with a columnar grain structure from the Electron Backscattered Diffraction (EBSD) measurements. Experimentally obtained starting microstructure and grain boundary properties are input for the three-dimensional grain growth simulation. In the computational model, minimization of the interface energy is the driving force for the grain boundary motion. The computed evolved microstructure is compared with the final experimental microstructure, after annealing at 550 ºC. Two different measures were introduced as methods of comparing experimental and computed microstructures. Modeling with anisotropic mobility explains a significant amount of mismatch between experiment and isotropic modeling. We have shown that isotropic modeling has very little predictive value. Microstructural evolution in columnar Aluminum foils can be correctly modeled with anisotropic parameters. We observed a strong similarity between grain growth experiments and anisotropic three-dimensional simulations.

  18. Linking Experimental Characterization and Computational Modeling in Microstructural Evolution

    Energy Technology Data Exchange (ETDEWEB)

    Demirel, Melik Cumhur [Univ. of California, Berkeley, CA (United States)

    2002-06-01

    It is known that by controlling microstructural development, desirable properties of materials can be achieved. The main objective of our research is to understand and control interface dominated material properties, and finally, to verify experimental results with computer simulations. In order to accomplish this objective, we studied the grain growth in detail with experimental techniques and computational simulations. We obtained 5170-grain data from an Aluminum-film (120μm thick) with a columnar grain structure from the Electron Backscattered Diffraction (EBSD) measurements. Experimentally obtained starting microstructure and grain boundary properties are input for the three-dimensional grain growth simulation. In the computational model, minimization of the interface energy is the driving force for the grain boundary motion. The computed evolved microstructure is compared with the final experimental microstructure, after annealing at 550 ºC. Two different measures were introduced as methods of comparing experimental and computed microstructures. Modeling with anisotropic mobility explains a significant amount of mismatch between experiment and isotropic modeling. We have shown that isotropic modeling has very little predictive value. Microstructural evolution in columnar Aluminum foils can be correctly modeled with anisotropic parameters. We observed a strong similarity

  19. Experimental Oral Candidiasis in Animal Models

    Science.gov (United States)

    Samaranayake, Yuthika H.; Samaranayake, Lakshman P.

    2001-01-01

    Oral candidiasis is as much the final outcome of the vulnerability of the host as of the virulence of the invading organism. We review here the extensive literature on animal experiments mainly appertaining to the host predisposing factors that initiate and perpetuate these infections. The monkey, rat, and mouse are the choice models for investigating oral candidiasis, but comparisons between the same or different models appear difficult, because of variables such as the study design, the number of animals used, their diet, the differences in Candida strains, and the duration of the studies. These variables notwithstanding, the following could be concluded. (i) The primate model is ideal for investigating Candida-associated denture stomatitis since both erythematous and pseudomembranous lesions have been produced in monkeys with prosthetic plates; they are, however, expensive and difficult to obtain and maintain. (ii) The rat model (both Sprague-Dawley and Wistar) is well proven for observing chronic oral candidal colonization and infection, due to the ease of breeding and handling and their ready availability. (iii) Mice are similar, but in addition there are well characterized variants simulating immunologic and genetic abnormalities (e.g., athymic, euthymic, murine-acquired immune deficiency syndrome, and severe combined immunodeficient models) and hence are used for short-term studies relating the host immune response and oral candidiasis. Nonetheless, an ideal, relatively inexpensive model representative of the human oral environment in ecological and microbiological terms is yet to be described. Until such a model is developed, researchers should pay attention to standardization of the experimental protocols described here to obtain broadly comparable and meaningful data. PMID:11292645

  20. Experimental Analysis of Team Performance: Methodological Developments and Research Results.

    Science.gov (United States)

    1982-07-06

    most consistent sleep periods across days, and S3 showed a clear reorientation in his sleep episodes that persisted throughout Days 7-10. These latter...shifted her sleep pattern on Day 8, and she thereafter commenced sleep periods in the early hours (e.&., 1200) of an experimental "day." Finally, the...experiment. The novitiate participant is identified as "S4." Although the behavioral program was not oriented to time markers, sleep periods were generally

  1. 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...

  2. Aqueous two-phase systems of polyoxyethylene lauryl ether and potassium gluconate/potassium oxalate/potassium citrate at different temperature-experimental results and modeling of (liquid + liquid) equilibrium data

    International Nuclear Information System (INIS)

    Lu, Yang; Hao, Tongfan; Zhou, Yan; Han, Juan; Tan, Zhenjiang; Yan, Yongsheng

    2014-01-01

    Highlights: • The phase diagrams of POELE10-organic salts ATPSs were determined experimentally. • The experiential equations were used to correlate the binodal data. • The effect of salt on the binodal curve for the studied systems has been discussed. • The LLE data were correlated using the thermodynamic model. -- Abstract: The binodal data for the systems containing the POELE10 and KC 6 H 11 O 7 /K 2 C 2 O 4 /K 3 C 6 H 5 O 7 were determined at the T = (288.15, 298.15, 308.15) K. The three experiential equations were used to fit the binodal data and they achieved the satisfactory fitting effect. The effect of salt type on the phase-seperation ability of salt was studied. It was found that the phase-seperation ability of the salt with the higher valence anion is stronger than that with lower valence anion, namely, the order of the phase-seperation ability for the investigated salts is potassium citrate > potassium oxalate > potassium gluconate, which is also validated by the effective excluded volume (EEV). The (liquid + liquid) equilibrium data for the studied systems were determined and correlated by using the Pitzer–Debye–Hückel equation and Chen-NRTL model along with the Flory–Huggins equation, and good agreement was obtained with using these thermodynamic models

  3. Comparison of experimental and simulation results of 2D-draw-bend springback

    OpenAIRE

    T. Da Sisva Botelho; E. Bayraktar; G. Inglebert

    2006-01-01

    Purpose: This paper presents the results of experimental, analytical and numerical studies of draw-bendspringback on the response of steel blank strips.Design/methodology/approach: Springback, the elastically-driven change of shape of a part after forming, hasbeen simulated with 2-D plane strain finite elements model (ABAQUS). Springback simulations compared withexperimental test results under some test conditions and also sidewall curls were further discussed in this paper.Findings: The resu...

  4. INTERFACE DEFEAT OF LONG RODS IMPACTING BOROSILICATE GLASS EXPERIMENTAL RESULTS

    Science.gov (United States)

    2009-02-01

    impact velocity vc consumption velocity vF failure front velocity tCu time to penetrate the Cu buffer or cover plate tdwell time interval that rod...dwelled on glass surface = tpen – tCu tpen time to begin penetration after impact vhydro hydrodynamic penetration velocity, Eqn. (4) ρt target...impact velocity for bare borosilicate glass. Table 4. Further Analyses of Experimental Data oc dCu h vp tCu tpen tdwell Exp. [mm] [mm] [mm] [m/s

  5. Observer Based Sliding Mode Attitude Control: Theoretical and Experimental Results

    Directory of Open Access Journals (Sweden)

    U. Jørgensen

    2011-07-01

    Full Text Available In this paper we present the design of a sliding mode controller for attitude control of spacecraft actuated by three orthogonal reaction wheels. The equilibrium of the closed loop system is proved to be asymptotically stable in the sense of Lyapunov. Due to cases where spacecraft do not have angular velocity measurements, an estimator for the generalized velocity is derived and asymptotic stability is proven for the observer. The approach is tested on an experimental platform with a sphere shaped Autonomous Underwater Vehicle SATellite: AUVSAT, developed at the Norwegian University of Science and Technology.

  6. Experimental validation of the multiphase extended Leblond's model

    Science.gov (United States)

    Weisz-Patrault, Daniel

    2017-10-01

    Transformation induced plasticity is a crucial contribution of the simulation of several forming processes involving phase transitions under mechanical loads, resulting in large irreversible strain even though the applied stress is under the yield stress. One of the most elegant and widely used models is based on analytic homogenization procedures and has been proposed by Leblond et al. [1-4]. Very recently, a simple extension of the Leblond's model has been developed by Weisz-Patrault [8]. Several product phases are taken into account and several assumptions are relaxed in order to extend the applicability of the model. The present contribution compares experimental tests with numerical computations, in order to discuss the validity of the developed theory. Thus, experimental results extracted from the existing literature are analyzed. Results show a good agreement between measurements and theoretical computations.

  7. Modeling a nuclear reactor for experimental purposes

    International Nuclear Information System (INIS)

    Berta, V.T.

    1980-01-01

    The Loss-of-Fluid Test (LOFT) Facility is a scale model of a commercial PWR and is as fully functional and operational as the generic commercial counterpart. LOFT was designed and built for experimental purposes as part of the overall NRC reactor safety research program. The purpose of LOFT is to assess the capability of reactor safety systems to perform their intended functions during occurrences of off-normal conditions in a commercial nuclear reactor. Off-normal conditions arising from large and small break loss-of-coolant accidents (LOCA), operational transients, and anticipated transients without scram (ATWS) were to be investigated. This paper describes the LOFT model of the generic PWR and summarizes the experiments that have been conducted in the context of the significant findings involving the complex transient thermal-hydraulics and the consequent effects on the commercial reactor analytical licensing techniques. Through these techniques the validity of the LOFT model as a scaled counterpart of the generic PWR is shown

  8. Experimental models of autoimmune inflammatory ocular diseases

    Directory of Open Access Journals (Sweden)

    Fabio Gasparin

    2012-04-01

    Full Text Available Ocular inflammation is one of the leading causes of blindness and loss of vision. Human uveitis is a complex and heterogeneous group of diseases characterized by inflammation of intraocular tissues. The eye may be the only organ involved, or uveitis may be part of a systemic disease. A significant number of cases are of unknown etiology and are labeled idiopathic. Animal models have been developed to the study of the physiopathogenesis of autoimmune uveitis due to the difficulty in obtaining human eye inflamed tissues for experiments. Most of those models are induced by injection of specific photoreceptors proteins (e.g., S-antigen, interphotoreceptor retinoid-binding protein, rhodopsin, recoverin, phosducin. Non-retinal antigens, including melanin-associated proteins and myelin basic protein, are also good inducers of uveitis in animals. Understanding the basic mechanisms and pathogenesis of autoimmune ocular diseases are essential for the development of new treatment approaches and therapeutic agents. The present review describes the main experimental models of autoimmune ocular inflammatory diseases.

  9. Experimental measurements and thermodynamic modeling of refrigerant hydrates dissociation conditions

    International Nuclear Information System (INIS)

    Hashemi, Hamed; Babaee, Saeedeh; Mohammadi, Amir H.; Naidoo, Paramespri; Ramjugernath, Deresh

    2015-01-01

    Highlights: • Dissociation conditions of refrigerant hydrates are studied experimentally and theoretically. • Refrigerants R23, R134a, R125a, R22, R410A, R407C and R507C are studied experimentally. • A thermodynamic model able to predict refrigerant hydrates dissociation conditions is proposed. • The results show good agreement between the experimental and predicted values. - Abstract: This study aims to investigate dissociation conditions of refrigerant hydrates both experimentally and theoretically. For this purpose, dissociation conditions of refrigerants R23, R134a, R125a, R22, R410A, R407C and R507C have been measured experimentally. A thermodynamic model that is able to predict refrigerant hydrates dissociation conditions in the various phase equilibrium regions has been proposed as well. Refrigerants modeled in this study include pure refrigerants: R11, R12, R13, R22, R23, R32, R134a, R141b, R143a, R125a, R152a, and mixed refrigerants: R11 + R12, R11 + R114, R12 + R114, R32 + R125a + R134a (R407C), R32 + R125a (R410A). For the modeling of the fluid and hydrate phases, the Peng-Robinson equation of state modified by Stryjek and Vera and the MHV2 G E -EoS mixing rule along with the UNIFAC (original) activity coefficient and van der Waals–Platteeuw (vdW–P) models were employed. The results show good agreement between the experimental and predicted values

  10. Consumers’ Need of Privacy Protection – Experimental Results

    Directory of Open Access Journals (Sweden)

    Elżbieta Babula

    2017-06-01

    Full Text Available Protection of privacy in the information age is a growing challenge. Corporations and other institutions collect data and utilize them for various purposes, not all of which may be in favour of individuals. Yet still little is known of how individuals perceive the value of privacy and what is the individuals’ awareness of costs and benefits associated with data sharing. This article presents the experimental research on factors determining privacy behavior of consumers. We provide evidence, that the need of privacy protection depends on gender and is affected by priming. On the other hand, nor the type of purchased good nor the decision-making method had the significant impact in our study on willingness to disclose private data.

  11. Experimental MR imaging with Gd-DOTA: Preliminary results

    International Nuclear Information System (INIS)

    Schouman-Claeys, E.; Kien, P.; Caille, J.M.; Bonnemain, B.; Frija, G.

    1986-01-01

    To evaluate the paramagnetic properties of a new gadolinium chelate, Gd-DOTA, in vitro and in vivo MR imaging was performed with a 0.5-T supraconductive magnet. The in vitro study consisted in measuring the MR signal obtained with various concentrations of Gd-DOTA and Gd-DTPA in different solutions. Potentialization of the paramagnetic properties of both DOTA and DTPA can be achieved by deuterium, glycerol, and protein solutions. The in vivo study was performed in rabbits with various experimental lesions. Enhancement of anatomic details was obtained with both Gd-DOTA and Gd-DTPA. There was no significant difference between Gd-DOTA and Gd-DTPA, both for in vitro and in vivo experiments. Gd-DOTA appears to be a potential paramagnetic agent for MR imaging

  12. Defining Dynamic Characteristics of Multilink Pendulum System with Comparison of the Calculated and Experimental Results

    Directory of Open Access Journals (Sweden)

    V. A. Gribkov

    2015-01-01

    Full Text Available We consider the multilink pendulum system consisting of six physical pendulums. A pendulum (carrier has inertia parameters, which significantly exceed the remaining (carried ones placed on the carrier. In addition to the system under analysis, in particular, the paper presents a design scheme for a two-stage liquid fuel rocket using pendulums as the analogues of fluctuating fuel. Pendulum models also find application to solve problems of stabilization of space tether systems. The objective of the study is to determine dynamic characteristics of the said sixmembered pendulum system, as well as to identify specific dynamic properties inherent in objects of this kind. Dynamic characteristics of the system are determined by calculations. A physical model of the pendulum allowed us to compare the calculated and experimental results. To conduct the frequency tests of the pendulum model three pilot units have been created. The first two units turned out to be inappropriate for fulfilling the experimental tasks for various reasons. The third unit enabled us to obtain desirable experimental results. The "calculation–experiment” discrepancy on the natural frequencies of the pendulum model for the majority of frequencies was less than 5%. We analyzed the dynamic features of multilink pendulum systems "carried by the carrier unit links". The analysis results are applicable to the above-noted object classes of rocket and space technology.

  13. Effects of Anethole in Nociception Experimental Models

    Directory of Open Access Journals (Sweden)

    Alessandra Mileni Versuti Ritter

    2014-01-01

    Full Text Available This study investigated the antinociceptive activity of anethole (anethole 1-methoxy-4-benzene (1-propenyl, major compound of the essential oil of star anise (Illicium verum, in different experimental models of nociception. The animals were pretreated with anethole (62.5, 125, 250, and 500 mg/kg one hour before the experiments. To eliminate a possible sedative effect of anethole, the open field test was conducted. Anethole (62.5, 125, 250, and 500 mg/kg showed an antinociceptive effect in the writhing model induced by acetic acid, in the second phase of the formalin test (125 and 250 mg/kg in the test of glutamate (62.5, 125, and 250 mg/kg, and expresses pain induced by ACF (250 mg/kg. In contrast, anethole was not able to increase the latency time on the hot plate and decrease the number of flinches during the initial phase of the formalin test in any of the doses tested. It was also demonstrated that anethole has no association with sedative effects. Therefore, these data showed that anethole, at all used doses, has no sedative effect and has an antinociceptive effect. This effect may be due to a decrease in the production/release of inflammatory mediators.

  14. Effects of anethole in nociception experimental models.

    Science.gov (United States)

    Ritter, Alessandra Mileni Versuti; Ames, Franciele Queiroz; Otani, Fernando; de Oliveira, Rubia Maria Weffort; Cuman, Roberto Kenji Nakamura; Bersani-Amado, Ciomar Aparecida

    2014-01-01

    This study investigated the antinociceptive activity of anethole (anethole 1-methoxy-4-benzene (1-propenyl)), major compound of the essential oil of star anise (Illicium verum), in different experimental models of nociception. The animals were pretreated with anethole (62.5, 125, 250, and 500 mg/kg) one hour before the experiments. To eliminate a possible sedative effect of anethole, the open field test was conducted. Anethole (62.5, 125, 250, and 500 mg/kg) showed an antinociceptive effect in the writhing model induced by acetic acid, in the second phase of the formalin test (125 and 250 mg/kg) in the test of glutamate (62.5, 125, and 250 mg/kg), and expresses pain induced by ACF (250 mg/kg). In contrast, anethole was not able to increase the latency time on the hot plate and decrease the number of flinches during the initial phase of the formalin test in any of the doses tested. It was also demonstrated that anethole has no association with sedative effects. Therefore, these data showed that anethole, at all used doses, has no sedative effect and has an antinociceptive effect. This effect may be due to a decrease in the production/release of inflammatory mediators.

  15. Tendon healing in vivo. An experimental model.

    Science.gov (United States)

    Abrahamsson, S O; Lundborg, G; Lohmander, L S

    1989-01-01

    Flexor tendon segments were incubated in a diffusion chamber in the subcutis of rabbits. Tendons incubated up to 6 weeks in the diffusion chamber showed proliferating and migrating cells from the epitenon cell layer as well as viable endotenon cells. Explants frozen in liquid nitrogen prior to incubation showed no signs of extrinsic cell contamination and remained non-viable indicating that no cell penetration occurred through the Millipore filter and that cell division seen in non-frozen and incubated tendons was an expression of intrinsic cellular proliferative capacity of the tendon. In tendon segments incubated in chambers for three weeks, collagen synthesis was reduced by 50% and the rate of cell proliferation measured as 3H-thymidine incorporation, was 15 times that of native tendons. Frozen and incubated tendons showed only traces of remaining matrix synthesis or cell proliferation. With this experimental model we have histologically and biochemically shown that tendons may survive and heal while the nutrition exclusively could be based on diffusion and the tendons have an intrinsic capacity of healing. The described model enables further studies on tendon healing and its regulation.

  16. Comparison of analysis results with experimental results for ENEA and CRIEPI rubber bearings

    International Nuclear Information System (INIS)

    Yoo, B.; Lee, J.H.; Koo, G.H.

    1993-01-01

    In this paper, the preliminary structural analyses of ENEA HDRB and CRIEPI NRB were performed by using computer code ABAQUS, and the analysis results were compared with the test results provided by Italy and Japan thru IAEA. The test data for the rubbers used for the fabrication of bearings were also provided thru IAEA, and were utilized for the formulation of the rubber models for the analyses. The analyses performed for the rubber bearings are for the combined compression and shear and for the compression. The analysis results show a good agreement in shear strains when compared with the test results of HDRB and NRB for the combined compression and shear and for the compression benchmarks, but show relatively smaller responses in displacements for the compression with offsets benchmarks. (author)

  17. Numerical modeling of nitrogen oxide emission and experimental verification

    Directory of Open Access Journals (Sweden)

    Szecowka Lech

    2003-12-01

    Full Text Available The results of nitrogen reduction in combustion process with application of primary method are presented in paper. The reduction of NOx emission, by the recirculation of combustion gasses, staging of fuel and of air was investigated, and than the reduction of NOx emission by simultaneous usage of the mentioned above primary method with pulsatory disturbances.The investigations contain numerical modeling of NOx reduction and experimental verification of obtained numerical calculation results.

  18. Point Cloud Based Visibility Analysis : first experimental results

    NARCIS (Netherlands)

    Zhang, G.; van Oosterom, P.J.M.; Verbree, E.; Bregt, Arnold; Sarjakoski, Tapani; Lammeren, Ron van; Rip, Frans

    2017-01-01

    Visibility computed from a LiDAR point cloud offers several advantages compared to using a gridded digital height-model. With a higher resolution and detailed information, point cloud data can provide precise analysis as well as an opportunity to avoid the process of generating a surface

  19. Impact mechanics of ship collisions and validations with experimental results

    DEFF Research Database (Denmark)

    Zhang, Shengming; Villavicencio, R.; Zhu, L.

    2017-01-01

    Closed-form analytical solutions for the energy released for deforming and crushing ofstructures and the impact impulse during ship collisions were developed and published inMarine Structures in 1998 [1]. The proposed mathematical models have been used bymany engineers and researchers although...

  20. Experimental Measurement, Analysis and Modelling of Dependency ...

    African Journals Online (AJOL)

    We propose a direct method of measurement of the total emissivity of opaque samples on a range of temperature around the ambient one. The method rests on the modulation of the temperature of the sample and the infra-red signal processing resulting from the surface of the sample we model the total emissivity obtained ...

  1. Experimental results with hydrogen fueled internal combustion engines

    Science.gov (United States)

    De Boer, P. C. T.; Mclean, W. J.; Homan, H. S.

    1975-01-01

    The paper focuses on the most important experimental findings for hydrogen-fueled internal combustion engines, with particular reference to the application of these findings to the assessment of the potential of hydrogen engines. Emphasis is on the various tradeoffs that can be made, such as between maximum efficiency, maximum power, and minimum NO emissions. The various possibilities for induction and ignition are described. Some projections are made about areas in which hydrogen engines may find their initial application and about optimum ways to design such engines. It is shown that hydrogen-fueled reciprocal internal combustion engines offer important advantages with respect to thermal efficiency and exhaust emissions. Problems arising from preignition can suitably be avoided by restricting the fuel-air equivalence ratio to values below about 0.5. The direct cylinder injection appears to be a very attractive way to operate the engine, because it combines a wide range of possible power outputs with a high thermal efficiency and very low NO emissions at part loads.

  2. Experimental Investigation of the Vehicle–Ground Interaction – Experiment Preparation and Preliminary Results

    Directory of Open Access Journals (Sweden)

    Valašková Veronika

    2017-12-01

    Full Text Available Interaction of the moving vehicle and the ground represents the actual engineering, environmental and economic problem. Due to the complexity of the problem, a combination of the experimental measurement and the computational simulation to understand the interaction mechanism is the most beneficial approach. Results of the in-situ observation serve as an input for the numerical analysis and also as a background for the calibration of the model. Presented paper brings the summary of the experiment preparation and preliminary results which are necessary for further analyses and numerical models. Computational simulations will be helpful for understanding the vehicle-ground interaction when inputs will be verified by the experimental way at known boundary conditions.

  3. Molten carbonate fuel cell: dynamic numerical modeling and experimental investigation

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Elisangela Martins [National Institute for Space Research, Cachoeira Paulista, SP (Brazil). Combustion and Propulsion Lab.], e-mail: elisangela@lcp.inpe.br; Jabbari, Faryar [University of California, Irvine, CA (United States). Mechanical and Aerospace Engineering Dept.], e-mail: fjabbari@uci.edu; Brouwer, Jacob [University of California, Irvine, CA (United States). National Fuel Cell Research Center], e-mail: jb@nfcrc.uci.edu

    2006-07-01

    In this paper, a detailed model incorporating simplified geometric resolution of a molten carbonate fuel cell (MCFC) with detailed and dynamic simulation of all physical, chemical, and electrochemical processes in the stream-wise direction is presented. The model was developed using mass and momentum conservation, electrochemical and chemical reaction mechanisms, and heat transfer. Results from the model are compared with data from an experimental MCFC unit. Furthermore, the model was applied to predict dynamic variations of voltage, current and temperature in an MCFC as it responds to varying load demands. The voltage was evaluated by applying a model developed by Yu h and Selman (1991a, 1991b). The results show that the model can be used to predict voltage and dynamic response characteristics of an MCFC accurately and consistently for a variety of temperatures and pressures. (author)

  4. Polymorphic transition of tin under shock wave compression: Experimental results

    Directory of Open Access Journals (Sweden)

    Sinatti F.

    2012-08-01

    Full Text Available In this work, the β-bct polymorphic transition in tin is investigated by means of plate impact experiments. The Sn target surface is observed in a partially released state obtained thanks to a transparent lithium fluoride (LiF anvil. We report both measurements of interface velocity and temperature obtained using Photon Doppler Velocimetry and IR optical pyrometer on shock-loaded tin from 8 to 16 GPa. We show that the Mabire Model EOS associated to the SCG plasticity model provides an overall good estimate of the velocity profiles. However, depnding on the shock amplitude, its prediction of the temperature profile may be less satisfactory, hence underlining the need for future improvements in terms of phase transition kinetics description.

  5. RESULTS OF EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF THE HERRING SALTING

    Directory of Open Access Journals (Sweden)

    M. V. Shumanova

    2015-01-01

    Full Text Available To the salting process of fish many studies are devoted, both in experimental and in theoretical terms. Study of features of fish salting in historical terms can be divided into 3 groups. One group of researchers believes that osmotic pressure has a major influence during the salting process. Another group attributed this process to the influence of molecular diffusion. The third group considers that during this process takes place both osmosis and diffusion. Determination of the main characteristics (salinity, diffusion coefficients, time of salting, etc. is a very time-consuming task. This leads to the idea of searching for innovative research methods. Current state of science, in addition to theoretical solutions points to the possibility to determine the basic characteristics of salting and applying methods associated with the interaction of ultrasound and electromagnetic radiation with matter. In our studies, we have been producing laser beam scanning of salt solution and fish meat thickness. Scattered radiation is determined by the salt concentration, diffusion coefficients, the size of the diffusing particles. This method is called a photon correlation spectroscopy. It has been applied in our work. The dependence of the scattered light intensity on the concentration of sodium chloride solution (brine has been investigated. According to diffusion coefficient a diffusion in solution to herring skin a conclusion was made that salt solution obtains fractal structure and its size was determined. Also we determined diffusion coefficients depending on the temperature in the layers. The layers are brine-leather, leather, and herring meat thickness. The process of diffusion-osmotic equilibrium revealed at temperatures of 10-12 ° C. Suggested the possibility of higher quality of fish salting at low temperatures. On the basis of the selfsimilar solution of the differential diffusion equation, a formula for calculating time salting fish was obtained

  6. Second harmonic emission of a quasi optical gyrotron: experimental results

    International Nuclear Information System (INIS)

    Alberti, S.; Tran, M.Q.; Hogge, J.P.; Tran, T.M.; Bondeson, A.; Muggli, P.; Isaak, B.; Joedlicke, B.; Mathews, H.G.

    1989-01-01

    A quasi-optical (Q.O) gyrotron designed for operation at the fundamental (Ω ce =100 GHz) exhibits simultaneous emission at Ω ce and 2Ω ce . For a beam current of 4A, 20% of the total RF power is emitted at 2Ω ce . In order to understand the influence of the presence of the second harmonic on the operation at the fundamental, an extensive set of measurement has been carried out. A comparison with a theoretical model will be presented. (author) 5 figs., 3 refs

  7. New experimental results on electron cooling at COSY-Juelich

    International Nuclear Information System (INIS)

    Dietrich, J.; Maier, R.; Prasuhn, D.; Stein, H.J.; Kobets, A.; Meshkov, I.; Sidorin, A.; Smirnov, A.

    2007-01-01

    Recent results of electron cooling of proton beams at COSY-Juelich are reported. Cooling at an electron energy of 70 keV has been studied for the first time. At the injection energy level of COSY, corresponding to 24.5 keV electron energy, the features of the cooled proton beam at extremely low intensities have been investigated in order to find out whether an ordering of the proton beam can be achieved. Such investigations are motivated by the results of a numerical simulation of the ordering process by the BETACOOL code. (author)

  8. Systematic integration of experimental data and models in systems biology.

    Science.gov (United States)

    Li, Peter; Dada, Joseph O; Jameson, Daniel; Spasic, Irena; Swainston, Neil; Carroll, Kathleen; Dunn, Warwick; Khan, Farid; Malys, Naglis; Messiha, Hanan L; Simeonidis, Evangelos; Weichart, Dieter; Winder, Catherine; Wishart, Jill; Broomhead, David S; Goble, Carole A; Gaskell, Simon J; Kell, Douglas B; Westerhoff, Hans V; Mendes, Pedro; Paton, Norman W

    2010-11-29

    The behaviour of biological systems can be deduced from their mathematical models. However, multiple sources of data in diverse forms are required in the construction of a model in order to define its components and their biochemical reactions, and corresponding parameters. Automating the assembly and use of systems biology models is dependent upon data integration processes involving the interoperation of data and analytical resources. Taverna workflows have been developed for the automated assembly of quantitative parameterised metabolic networks in the Systems Biology Markup Language (SBML). A SBML model is built in a systematic fashion by the workflows which starts with the construction of a qualitative network using data from a MIRIAM-compliant genome-scale model of yeast metabolism. This is followed by parameterisation of the SBML model with experimental data from two repositories, the SABIO-RK enzyme kinetics database and a database of quantitative experimental results. The models are then calibrated and simulated in workflows that call out to COPASIWS, the web service interface to the COPASI software application for analysing biochemical networks. These systems biology workflows were evaluated for their ability to construct a parameterised model of yeast glycolysis. Distributed information about metabolic reactions that have been described to MIRIAM standards enables the automated assembly of quantitative systems biology models of metabolic networks based on user-defined criteria. Such data integration processes can be implemented as Taverna workflows to provide a rapid overview of the components and their relationships within a biochemical system.

  9. Experimental, statistical, and biological models of radon carcinogenesis

    International Nuclear Information System (INIS)

    Cross, F.T.

    1991-09-01

    Risk models developed for underground miners have not been consistently validated in studies of populations exposed to indoor radon. Imprecision in risk estimates results principally from differences between exposures in mines as compared to domestic environments and from uncertainties about the interaction between cigarette-smoking and exposure to radon decay products. Uncertainties in extrapolating miner data to domestic exposures can be reduced by means of a broad-based health effects research program that addresses the interrelated issues of exposure, respiratory tract dose, carcinogenesis (molecular/cellular and animal studies, plus developing biological and statistical models), and the relationship of radon to smoking and other copollutant exposures. This article reviews experimental animal data on radon carcinogenesis observed primarily in rats at Pacific Northwest Laboratory. Recent experimental and mechanistic carcinogenesis models of exposures to radon, uranium ore dust, and cigarette smoke are presented with statistical analyses of animal data. 20 refs., 1 fig

  10. Experimental, statistical and biological models of radon carcinogenesis

    International Nuclear Information System (INIS)

    Cross, F.T.

    1992-01-01

    Risk models developed for underground miners have not been consistently validated in studies of populations exposed to indoor radon. Imprecision in risk estimates results principally from differences between exposures in mines as compared with domestic environments and from uncertainties about the interaction between cigarette smoking and exposure to radon decay products. Uncertainties in extrapolating miner data to domestic exposures can be reduced by means of a broad-based health effects research programme that addresses the interrelated issues of exposure, respiratory tract dose, carcinogenesis (molecular/cellular and animal studies, plus developing biological and statistical models) and the relationship of radon to smoking and other co-pollutant exposures. This article reviews experimental animal data on radon carcinogenesis observed primarily in rats at Pacific Northwest Laboratory. Recent experimental and mechanistic carcinogenesis models of exposures to radon, uranium ore dust, and cigarette smoke are presented with statistical analyses of animal data. (author)

  11. The behavior of delaminations in composite materials - experimental results

    Science.gov (United States)

    Chermoshentseva, A. S.; Pokrovskiy, A. M.; Bokhoeva, L. A.

    2016-02-01

    Delamination is one of the most common failure modes of composite materials. It may occur as a consequence of imperfections in the production process or the effects of external factors during the operational life of the composite laminates, such as the impact by foreign objects. This paper presents the results of mechanical tests and the optimum degrees of filling the composite materials (CM) with hydrophobic powder (Tarkosil T-20) depending on the latter mass concentration. The results present test samples of the CM with the underlying interlayer defects. The samples were fabricated of twenty-ply pre-preg (fiberglass or carbon fiber). The industrial grade glass is T-25 (VM) specification 6-11-380-76. The composite materials have nanosized additives in structure. The volume concentration of nanopowders is varying from 0.1% to 0.5%. This kind of research has been done for the first time.

  12. Status of the MEG Experiment: Timing Counter Experimental Results

    CERN Document Server

    Valle, R; Dussoni, S; Cecchet, G; Rossella, M; Zanello, D

    2005-01-01

    The Timing Counter (TC) of the MEG experiment must achieve a time resolution equal or better than 100 ps FWHM (σ = 42.5 ps). The results obtained, at the Beam Test Facility (BTF) of Frascati/Italy, on two TC prototypes elements, permitted the selection of the scintillator, providing the best timing resolution, achieving an average resolution of 92 ps FWHM (σ = 39.2 ps) with a plastic scintillator.

  13. Experimental and numerical analysis of a knee endoprosthesis numerical model

    Directory of Open Access Journals (Sweden)

    L. Zach

    2016-07-01

    Full Text Available The aim of this study is to create and verify a numerical model for a Medin Modular orthopedic knee-joint implant by investigating contact pressure, its distribution and contact surfaces. An experiment using Fuji Prescale pressure sensitive films and a finite element analysis (FEA using Abaqus software were carried out. The experimental data were evaluated using a special designed program and were compared with the results of the analysis. The designed evaluation program had been constructed on the basis of results obtained from a supplementary calibration experiment. The applicability of the numerical model for the real endoprosthesis behavior prediction was proven on the basis of their good correlation.

  14. 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)

  15. Quark-Gluon Plasma: from lattice simulations to experimental results

    Science.gov (United States)

    Aarts, G.; Allton, C.; Kelly, A.; Skullerud, J.-I.; Kim, S.; Harris, T.; Ryan, S. M.; Lombardo, M. P.

    2014-07-01

    Theoretical studies of quarkonia can elucidate some of the important properties of the quark-gluon plasma, the state of matter realised when the temperature exceeds (150) MeV, currently probed by heavy-ion collisions experiments at BNL and the LHC. We report on our results of lattice studies of bottomonia for temperatures in the range 100 MeV lessapprox T lessapprox 450 MeV, introducing and discussing the methodologies we have applied. Of particular interest is the analysis of the spectral functions, where Bayesian methods borrowed and adapted from nuclear and condensed matter physics have proven very successful.

  16. Quark gluon plasma: Overview and experimental results from E-735

    International Nuclear Information System (INIS)

    Turkot, F.; Alexopoulos, T.; Allen, C.

    1988-01-01

    A brief review of the phenomenology associated with the effort to produce and observe quark-gluon plasma in particle collisions is presented. E-735 has taken data during the 1987 Tevatron-Collider run at /square root/s = 1.8 TeV in pursuit of this goal. Results in the correlation of with multiplicity for charged particles and p/sub t/ distributions for Λ/sup o/ and /bar Lambda//sup o/ are presented. 32 refs., 10 figs., 2 tabs

  17. Development of experimental alloxan model of diabetes mellitus

    Directory of Open Access Journals (Sweden)

    V.V. Semenko

    2017-05-01

    Full Text Available Background. One of the main causes that lead to the disability of diabetic patients is diabetic retinopathy (DR. The relevance of the problem of DR necessitates the development of optimal experimental models on experimental animals to find effective ways of correcting this pathology. The purpose of our work was to develop an experimental alloxan model of type 1 diabetes mellitus (DM for the study of DR, which would not result in the lethal outcome of experimental animals under the action of alloxan; histological examination of changes in the tissues of the eyeball in the reproduction of the DM model for the selection of new effective methods for the metabolic treatment of DR in the early stages. Materials and methods. The experiment was carried out on white outbred Wistar rats weighing 180–200 g. The first group consisted of 20 animals that were not subjected to any influence, served as a control; second group — 30 animals, in which DM was modeled by administration of alloxan and fructose. Results. When modeling DR, vessel changes in the form of wall fibrosis, edema of the endothelium and vasospasm were found. There was also a decrease in the amount of pigment granules, dystrophic changes in the cells of the ganglionic layer and a layer of retinal rods and cones, which coincides with the descriptions of damage to the coats of the eyeball in patients with DM. Conclusions. In our studies, we have calculated the optimal dose of alloxan administration, which does not lead to the death of rats (the lethality of rats was absent and is an effective model not only of DM in general, but also of DR.

  18. Target Soil Impact Verification: Experimental Testing and Kayenta Constitutive Modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Broome, Scott Thomas [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Flint, Gregory Mark [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Dewers, Thomas [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Newell, Pania [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-11-01

    This report details experimental testing and constitutive modeling of sandy soil deformation under quasi - static conditions. This is driven by the need to understand constitutive response of soil to target/component behavior upon impact . An experimental and constitutive modeling program was followed to determine elastic - plastic properties and a compressional failure envelope of dry soil . One hydrostatic, one unconfined compressive stress (UCS), nine axisymmetric compression (ACS) , and one uniaxial strain (US) test were conducted at room temperature . Elastic moduli, assuming isotropy, are determined from unload/reload loops and final unloading for all tests pre - failure and increase monotonically with mean stress. Very little modulus degradation was discernable from elastic results even when exposed to mean stresses above 200 MPa . The failure envelope and initial yield surface were determined from peak stresses and observed onset of plastic yielding from all test results. Soil elasto - plastic behavior is described using the Brannon et al. (2009) Kayenta constitutive model. As a validation exercise, the ACS - parameterized Kayenta model is used to predict response of the soil material under uniaxial strain loading. The resulting parameterized and validated Kayenta model is of high quality and suitable for modeling sandy soil deformation under a range of conditions, including that for impact prediction.

  19. Silicon drift detector with reduced lateral diffusion: experimental results

    CERN Document Server

    Sonsky, J; Huizenga, John R; Hollander, R W; Eijk, C W E; Sarro, P M

    2000-01-01

    In a standard multi-anode silicon drift detector electron cloud broadening during the drifting towards the anode pixels deteriorates the energy and position resolution. This makes the detector less applicable for detection of low-energy X-rays. The signal charge sharing between several anodes can be eliminated by introducing sawtooth-shaped p sup + field strips. The sawtooth structure results in small electric fields directed parallel to the sensor surface and perpendicular to the drift direction which produce gutters. The drifting electrons are confined in these gutters of one saw tooth period wide. For a detector with a sawtooth period of 500 mu m, we have measured the maximum number of fully confined electrons as a function of the potential gutter depth induced by different sawtooth angles.

  20. Experimental results on low alpha electron-storage rings

    International Nuclear Information System (INIS)

    Robin, D.; Hama, H.; Nadji, A.

    1995-09-01

    The authors report on experiments performed in two synchrotron light sources, UVSOR and Super-ACO, where the momentum compaction factor is reduced in order to reduce the bunch length. By controlling the second-order momentum compaction factor, UVSOR and Super-ACO have managed to reduce the first-order momentum compaction factor by 100. At low current the resulting bunch lengths are less than 10 ps, a factor of 10 smaller than normal. Measurements of current dependent bunch lengthening in UVSOR are presented and the cause of the bunch lengthening is determined to be potential-well distortion. The authors also show that by operating with a negative momentum compaction factor, SuperACO has achieved shorter bunch lengthening and higher peak currents than at positive momentum compaction

  1. Exact results for chaotic scattering and experimental validation

    Science.gov (United States)

    Guhr, Thomas

    2017-12-01

    As scattering experiments are the key tool to obtain information on nuclei and other quantum systems, the foundations of scattering theory were laid already a long time ago. Compound nucleus scattering prompted the study of generic statistical features. In the Heidelberg approach, those are taken into account by assuming that the reaction zone is fully quantum chaotic. Later on, this approach turned out to be applicable to a large variety of systems on different scales, including classical wave systems. For a long time, the distribution of the off-diagonal scattering-matrix elements resisted analytical treatment. In two recent studies [1, 2], we fully solved this problem and we also carried out a comparison with data from microwave experiments. Some comment are made on our very recent results for the cross-section distributions.

  2. [Experimental results of erbium:YAG laser vitrectomy].

    Science.gov (United States)

    Mrochen, M; Petersen, H; Wüllner, C; Seiler, T

    1998-01-01

    Vitrectomy performed by conventional guillotine devices includes the risk of mechanical damage to retina as well as other ocular structures. The present study aims to investigate the efficacy of the Er:YAG laser for vitreous liquefaction. Vitreous liquefaction by means of Er:YAG laser pulses was performed using a special handpiece. The output of an Er:YAG laser operating at 2.94 microns was coupled into a ZrF optical fibre (length 2 m) which ended inside a cavity located at the quartz tip (diameter 320 microns) of the handpiece where tissue ablation took place. The viscosity of the liquefied vitreous was determined by rotation viscosimetry and compared to liquefied vitreous obtained by mechanical vitrectomy. In addition, the aspiration flow (ml/min) was correlated to the repetition/cutting rate of the laser and the cutter. The temperature rise at the handpiece was recorded with a micro thermocouple. The cutting threshold was determined to 5 mJ +/- 3 mJ at a pulse duration of 200 microseconds. The viscosity of the vitreous liquefied with the Er:YAG laser was 31 +/- 10 mPa s which is similar to the results of mechanical vitrectomy (42 +/- 19 mPa s) but significant less than that of normal vitreous (880 +/- 280 mPa s). The aspiration of the laser handpiece in dependence to the repetition rate increases linear up to 2.6 ml/min at 30 Hz. The temperature increase at the handpiece was < 1 K under vitrectomy conditions (aspiration and irrigation) with an averaged laser power of 0.3 W (10 mJ at 30 Hz). The decreased vacuum forces used by the laser vitrectomy system may result in less mechanical stress to the retina as well as intravitreal structures which may be attached to it. An Er:YAG laser vitrectomy system may offer the potential of fewer complications during vitrectomy.

  3. Experimental results: Pilot plant calcine dissolution and liquid feed stability

    International Nuclear Information System (INIS)

    Herbst, R.S.; Fryer, D.S.; Brewer, K.N.; Johnson, C.K.; Todd, T.A.

    1995-02-01

    The dissolution of simulated Idaho Chemical Processing Plant pilot plant calcines, containing none of the radioactive actinides, lanthanides or fission products, was examined to evaluate the solubility of calcine matrix materials in acidic media. This study was a necessary precursor to dissolution and optimization experiments with actual radionuclide-containing calcines. The importance of temperature, nitric acid concentration, ratio of acid volume to calcine mass, and time on the amount, as a weight percentage of calcine dissolved, was evaluated. These parameters were studied for several representative pilot plant calcine types: (1) Run No. 74 Zirconia calcine; (2) Run No. 17 Zirconia/Sodium calcine; (3) Run No. 64 Zirconia/Sodium calcine; (3) Run No. 1027 Alumina calcine; and (4) Run No. 20 Alumina/Zirconia/Sodium calcine. Statistically designed experiments with the different pilot plant calcines indicated the effect of the studied process variables on the amount of calcine dissolved decreases in the order: Acid/Calcine Ratio > Temperature > HNO 3 Concentration > Dissolution Time. The following conditions are suitable to achieve greater than 90 wt. % dissolution of most Zr, Al, or Na blend calcines: (1) Maximum nitric acid concentration of 5M; (2) Minimum acid/calcine ratio of 10 mL acid/1 gram calcine; (3) Minimum dissolution temperature of 90 degrees C; and (4) Minimum dissolution time of 30 minutes. The formation of calcium sulphate (CaSO 4 ) precipitates was observed in certain dissolved calcine solutions during the dissolution experiments. Consequently, a study was initiated to evaluate if and under what conditions the resulting dissolved calcine solutions would be unstable with regards to precipitate formation. The results indicate that precipitate formation in the calcine solutions prepared under the above proposed dissolution conditions are not anticipated

  4. Bridge Testing With Ground-Based Interferometric Radar: Experimental Results

    Science.gov (United States)

    Chiara, P.; Morelli, A.

    2010-05-01

    The research of innovative non-contact techniques aimed at the vibration measurement of civil engineering structures (also for damage detection and structural health monitoring) is continuously directed to the optimization of measures and methods. Ground-Based Radar Interferometry (GBRI) represents the more recent technique available for static and dynamic control of structures and ground movements. Dynamic testing of bridges and buildings in operational conditions are currently performed: (a) to assess the conformity of the structure to the project design at the end of construction; (b) to identify the modal parameters (i.e. natural frequencies, mode shapes and damping ratios) and to check the variation of any modal parameters over the years; (c) to evaluate the amplitude of the structural response to special load conditions (i.e. strong winds, earthquakes, heavy railway or roadway loads). If such tests are carried out by using a non-contact technique (like GBRI), the classical issues of contact sensors (like accelerometers) are easily overtaken. This paper presents and discusses the results of various tests carried out on full-scale bridges by using a Stepped Frequency-Continuous Wave radar system.

  5. Experimentally increasing sedentary behavior results in decreased life satisfaction

    Directory of Open Access Journals (Sweden)

    Meghan K. Edwards

    2017-03-01

    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 participants were instructed to eliminate all exercise and restrict daily steps (as measured via pedometry to 5000 or less per day for one week. The control group was instructed to maintain regular levels of exercise and other physical activity for one week. Both groups completed the Satisfaction with Life Scale (SWLS pre-intervention and immediately post-intervention. Results: There was a significant group x time interaction (F = 32.75, P < 0.001, with post-hoc contrast tests indicating decreased SWLS score (indicating lower levels of life satisfaction in the intervention group during Visit 2 (post-intervention compared with Visit 1 (pre-intervention; this corresponded with a mean absolute (Visit 2 minus Visit 1 change of -8.58 (95% CI: -5.91, -11.24 for SWLS scores in the intervention group (31.1% reduction. Conclusion: A one-week sedentary behavior-inducing intervention may negatively impact life satisfaction in an active, young adult population. Regular physical activity may be imperative in avoiding negative life satisfaction-related consequences.

  6. First experimental results on the IShTAR testbed

    Energy Technology Data Exchange (ETDEWEB)

    D’Inca, R.; Jacquot, J.; Ochoukov, R.; Morgal, I.; Fünfgelder, H.; Faugel, H. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Crombe, K.; Louche, F.; Van Eester, D. [LPP-ERM-KMS, TEC partner, Brussels (Belgium); Heuraux, S.; Devaux, S.; Moritz, J.; Faudot, E. [Institut Jean Lamour UMR 7198 CNRS-Université de Lorraine, Nancy (France); Noterdaeme, J.-M. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Department of Applied Physics, Ghent University (Belgium)

    2015-12-10

    IShTAR (Ion cyclotron Sheath Test ARrangement) is a linear magnetized plasma test facility dedicated to the investigation of RF wave/plasma interaction [1] in the Ion Cyclotron Range of Frequencies (ICRF). It provides a better accessibility for the instrumentation than tokamaks while being representative of the neighboring region of the wave emitter. It is equipped with a magnetized plasma source (1 m long, 0.4 m diameter) powered by a helical antenna up to 3 kW at 11 MHz. We present the results of the first analysis of the plasma characteristics (plasma density, electron temperature) in function of the operating parameters (injected power, neutral pressure and magnetic field) as measured with fixed and movable Langmuir probes, spectrometer and cameras. The plasma is presently produced only by the helical antenna (no ICRF). We show that the plasma exists in three regime depending on the power level: the first two ones are stable and separated by a jump in density; a first spatial profile of the plasma density has been established for these modes; The third mode is unstable, characterized by strong oscillations of the plasma tube position.

  7. Regression Model Optimization for the Analysis of Experimental Data

    Science.gov (United States)

    Ulbrich, N.

    2009-01-01

    A candidate math model search algorithm was developed at Ames Research Center that determines a recommended math model for the multivariate regression analysis of experimental data. The search algorithm is applicable to classical regression analysis problems as well as wind tunnel strain gage balance calibration analysis applications. The algorithm compares the predictive capability of different regression models using the standard deviation of the PRESS residuals of the responses as a search metric. This search metric is minimized during the search. Singular value decomposition is used during the search to reject math models that lead to a singular solution of the regression analysis problem. Two threshold dependent constraints are also applied. The first constraint rejects math models with insignificant terms. The second constraint rejects math models with near-linear dependencies between terms. The math term hierarchy rule may also be applied as an optional constraint during or after the candidate math model search. The final term selection of the recommended math model depends on the regressor and response values of the data set, the user s function class combination choice, the user s constraint selections, and the result of the search metric minimization. A frequently used regression analysis example from the literature is used to illustrate the application of the search algorithm to experimental data.

  8. The rabbit as an experimental model in laryngology

    Directory of Open Access Journals (Sweden)

    Carneiro, Christiano de Giacomo

    2009-06-01

    Full Text Available Introduction: In the research in laryngology we normally use animal models. The animal experimentation may also contribute largely for this evolution, mainly for the easy access compared to human larynxes and for they are more easily controlled. Objective: The objective of this work is to analyze the laryngofissure with vocal cords graft as an experimental surgical technique in male adult rabbits. Method: We studied 46 New Zealand albino rabbits submitted to microsurgery in both vocal cords with autologous unilateral or bilateral graft of fat or fascia. Results: There were 4 losses of 3 animals until the first week of the postoperative period and another after 19 days after surgery. In the subsequent animals there were no infection, hematoma or sutures dehiscence. Conclusion: The study enables the conclusion that the experimental laryngofissure in rabbits is a safe method that may be used for laryngological studies.

  9. OPERA and MINOS Experimental Result Prove Big Bang Theory Invalid

    Science.gov (United States)

    Pressler, David E.

    2012-03-01

    The greatest error in the history of science is the misinterpretation of the Michelson-Morley Experiment. The speed of light was measured to travel at the same speed in all three directions (x, y, z axis) in ones own inertial reference system; however, c will always be measured as having an absolute different speed in all other inertial frames at different energy levels. Time slows down due to motion or a gravity field. Time is the rate of physical process. Speed = Distance/Time. If the time changes the distance must change. Therefore, BOTH mirrors must move towards the center of the interferometer and space must contract in all-three-directions; C-Space. Gravity is a C-Space condition, and is the cause of redshift in our universe-not motion. The universe is not expanding. OPERA results are directly indicated; at the surface of earth, the strength of the gravity field is at maximum-below the earth's surface, time and space is less distorted, C-Space; therefore, c is faster. Newtonian mechanics dictate that a spherical shell of matter at greater radii, with uniform density, produces no net force on an observer located centrally. An observer located on the sphere's surface, like our Earth's or a large sphere, like one located in a remote galaxy, will construct a picture centered on himself to be identical to the one centered inside the spherical shell of mass. Both observers will view the incoming radiation, emitted by the other observer, as redshifted, because they lay on each others radial line. The Universe is static and very old.

  10. Review of JT-60U experimental results in 2000

    International Nuclear Information System (INIS)

    2002-11-01

    The results of JT-60U experiments in 2000, from February to December, are reviewed. The performance under the full non-inductive current drive has been greatly advanced both in high β p H-mode plasmas and in reversed shear (RS) plasmas. In the high β p H-mode, with injection of the negative ion based neutral beam (NNB) of 360 keV and 4 MW into a high electron temperature plasma (T e (0) ∼ 13 keV), a high fusion triple product n D (0)T i (0)τ E = 2.0 x 10 20 keVm -3 s has been obtained at the plasma current of 1.5 MA, and the highest value of current drive efficiency of NNB (1.55 x 10 19 A/W/m 2 ) has been achieved. In RS, LHCD and NNB-CD were employed for current drive and high confinement (HH y2 ∼ 1.4) at high density (f GW ∼ 0.80) has been achieved. In the 110 GHz ECRF system, two more gyrotrons have been installed in addition to the one installed in 1999 and 1.5 MW was injected into the torus for 3 s. Complete stabilization of neoclassical tearing mode (NTM), realization of high confinement plasmas with T e ∼ T i , a high value (1 MA) of NNB-driven current in the high T e regime, and measurement of localized EC driven current were achieved with the upgraded EC system. The multiple pellet injection system has been newly installed. In high power NB heated plasmas, high-field-side pellet injection was more effective than low-field-side injection, and it extended the regime of high confinement high β p H-mode to a higher density. A new method, called CCS (Cauchy-condition surface method), for the control of the plasma position and shape in real-time became available and was found very useful especially for the control of plasma-wall clearance in LH and IC experiments. The active control of ITB strength by the switch of the injection direction of toroidal angular momentum was successfully demonstrated. In high triangularity H-mode plasmas, higher pressure and temperature at the edge pedestal were observed, which resulted in higher temperature and

  11. Selective experimental review of the Standard Model

    International Nuclear Information System (INIS)

    Bloom, E.D.

    1985-02-01

    Before disussing experimental comparisons with the Standard Model, (S-M) it is probably wise to define more completely what is commonly meant by this popular term. This model is a gauge theory of SU(3)/sub f/ x SU(2)/sub L/ x U(1) with 18 parameters. The parameters are α/sub s/, α/sub qed/, theta/sub W/, M/sub W/ (M/sub Z/ = M/sub W//cos theta/sub W/, and thus is not an independent parameter), M/sub Higgs/; the lepton masses, M/sub e/, Mμ, M/sub r/; the quark masses, M/sub d/, M/sub s/, M/sub b/, and M/sub u/, M/sub c/, M/sub t/; and finally, the quark mixing angles, theta 1 , theta 2 , theta 3 , and the CP violating phase delta. The latter four parameters appear in the quark mixing matrix for the Kobayashi-Maskawa and Maiani forms. Clearly, the present S-M covers an enormous range of physics topics, and the author can only lightly cover a few such topics in this report. The measurement of R/sub hadron/ is fundamental as a test of the running coupling constant α/sub s/ in QCD. The author will discuss a selection of recent precision measurements of R/sub hadron/, as well as some other techniques for measuring α/sub s/. QCD also requires the self interaction of gluons. The search for the three gluon vertex may be practically realized in the clear identification of gluonic mesons. The author will present a limited review of recent progress in the attempt to untangle such mesons from the plethora q anti q states of the same quantum numbers which exist in the same mass range. The electroweak interactions provide some of the strongest evidence supporting the S-M that exists. Given the recent progress in this subfield, and particularly with the discovery of the W and Z bosons at CERN, many recent reviews obviate the need for further discussion in this report. In attempting to validate a theory, one frequently searches for new phenomena which would clearly invalidate it. 49 references, 28 figures

  12. 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

  13. 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.

  14. CS model coil experimental log book

    International Nuclear Information System (INIS)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  15. 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.

  16. Automated detection of discourse segment and experimental types from the text of cancer pathway results sections.

    Science.gov (United States)

    Burns, Gully A P C; Dasigi, Pradeep; de Waard, Anita; Hovy, Eduard H

    2016-01-01

    Automated machine-reading biocuration systems typically use sentence-by-sentence information extraction to construct meaning representations for use by curators. This does not directly reflect the typical discourse structure used by scientists to construct an argument from the experimental data available within a article, and is therefore less likely to correspond to representations typically used in biomedical informatics systems (let alone to the mental models that scientists have). In this study, we develop Natural Language Processing methods to locate, extract, and classify the individual passages of text from articles' Results sections that refer to experimental data. In our domain of interest (molecular biology studies of cancer signal transduction pathways), individual articles may contain as many as 30 small-scale individual experiments describing a variety of findings, upon which authors base their overall research conclusions. Our system automatically classifies discourse segments in these texts into seven categories (fact, hypothesis, problem, goal, method, result, implication) with an F-score of 0.68. These segments describe the essential building blocks of scientific discourse to (i) provide context for each experiment, (ii) report experimental details and (iii) explain the data's meaning in context. We evaluate our system on text passages from articles that were curated in molecular biology databases (the Pathway Logic Datum repository, the Molecular Interaction MINT and INTACT databases) linking individual experiments in articles to the type of assay used (coprecipitation, phosphorylation, translocation etc.). We use supervised machine learning techniques on text passages containing unambiguous references to experiments to obtain baseline F1 scores of 0.59 for MINT, 0.71 for INTACT and 0.63 for Pathway Logic. Although preliminary, these results support the notion that targeting information extraction methods to experimental results could provide

  17. Results of an Experimental Study of the Langlee Wave Energy Converter

    DEFF Research Database (Denmark)

    Pecher, Arthur; Kofoed, Jens Peter; Espedal, J.

    2010-01-01

    This paper presents the results of the first experimental study of the Langlee wave energy converter (WEC), a semi-submerged oscillating wave surge converter. Its design extracts the energy from the surge motion of the waves through two pairs of working flaps, called water wings, which are placed...... symmetrically opposing each other. The results predict the power production performance of the Langlee WEC model for two locations of interest, a generic offshore location in the Danish part of the North Sea and at Horns Rev 1, a Danish offshore wind farm....

  18. Validation of the newborn larynx modeling with aerodynamical experimental data.

    Science.gov (United States)

    Nicollas, R; Giordano, J; Garrel, R; Medale, M; Caminat, P; Giovanni, A; Ouaknine, M; Triglia, J M

    2009-06-01

    Many authors have studied adult's larynx modelization, but the mechanisms of newborn's voice production have very rarely been investigated. After validating a numerical model with acoustic data, studies were performed on larynges of human fetuses in order to validate this model with aerodynamical experiments. Anatomical measurements were performed and a simplified numerical model was built using Fluent((R)) with the vocal folds in phonatory position. The results obtained are in good agreement with those obtained by laser Doppler velocimetry (LDV) and high-frame rate particle image velocimetry (HFR-PIV), on an experimental bench with excised human fetus larynges. It appears that computing with first cry physiological parameters leads to a model which is close to those obtained in experiments with real organs.

  19. Experimentally testing the standard cosmological model

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, D.N. (Chicago Univ., IL (USA) Fermi National Accelerator Lab., Batavia, IL (USA))

    1990-11-01

    The standard model of cosmology, the big bang, is now being tested and confirmed to remarkable accuracy. Recent high precision measurements relate to the microwave background; and big bang nucleosynthesis. This paper focuses on the latter since that relates more directly to high energy experiments. In particular, the recent LEP (and SLC) results on the number of neutrinos are discussed as a positive laboratory test of the standard cosmology scenario. Discussion is presented on the improved light element observational data as well as the improved neutron lifetime data. alternate nucleosynthesis scenarios of decaying matter or of quark-hadron induced inhomogeneities are discussed. It is shown that when these scenarios are made to fit the observed abundances accurately, the resulting conclusions on the baryonic density relative to the critical density, {Omega}{sub b}, remain approximately the same as in the standard homogeneous case, thus, adding to the robustness of the standard model conclusion that {Omega}{sub b} {approximately} 0.06. This latter point is the deriving force behind the need for non-baryonic dark matter (assuming {Omega}{sub total} = 1) and the need for dark baryonic matter, since {Omega}{sub visible} < {Omega}{sub b}. Recent accelerator constraints on non-baryonic matter are discussed, showing that any massive cold dark matter candidate must now have a mass M{sub x} {approx gt} 20 GeV and an interaction weaker than the Z{sup 0} coupling to a neutrino. It is also noted that recent hints regarding the solar neutrino experiments coupled with the see-saw model for {nu}-masses may imply that the {nu}{sub {tau}} is a good hot dark matter candidate. 73 refs., 5 figs.

  20. SIMULATION AND EXPERIMENTAL RESULTS FOR THE CLOSED LOOP CONTROLLED DC TO DC FORWARD CONVERTER

    Directory of Open Access Journals (Sweden)

    A. Palamalai VIJAYAKUMAR

    2017-06-01

    Full Text Available A Closed loop controlled DC to DC forward converter is a requisite for the server SMPS system. High efficiency, Isolation, Steady state voltage, Transient response, High switching frequency, reduced noises and range of steady state are all necessary requirements for the forward converter. In this paper, a 40 V forward converter for charging the battery of server SMPS is proposed. The proposed converter consists of a NPC-ARS circuit for soft switching on the primary side and an isolation transformer and a rectifier structure on the secondary side. With this modified NPC-ARS circuit topology, soft switching occurs during conversion and reduces the switching loss in this system. This paper proposed the simulation of closed loop controlled circuit, for the forward converter with RCD snubber, double forward converter and the Modified forward converter are analyzed and discussed in this paper. From comparison of performance in the closed loop model, a suitable converter is proposed for the sever SMPS system. The proposed circuit achieves steady state voltage, when the disturbance occurs. A 40 V proposed circuit is designed as experimental model to verify and compare the simulation and experimental results. This paper proposed the simulation and experimental results of the forward converter.

  1. Systematic effects in CALOR simulation code to model experimental configurations

    International Nuclear Information System (INIS)

    Job, P.K.; Proudfoot, J.; Handler, T.

    1991-01-01

    CALOR89 code system is being used to simulate test beam results and the design parameters of several calorimeter configurations. It has been bench-marked against the ZEUS, Dθ and HELIOS data. This study identifies the systematic effects in CALOR simulation to model the experimental configurations. Five major systematic effects are identified. These are the choice of high energy nuclear collision model, material composition, scintillator saturation, shower integration time, and the shower containment. Quantitative estimates of these systematic effects are presented. 23 refs., 6 figs., 7 tabs

  2. Experimental model of heterotopic ossification in Wistar rats

    Energy Technology Data Exchange (ETDEWEB)

    Zotz, T.G.G. [Escola Politécnica, Programa de Pós-Graduação em Tecnologia em Saúde, Pontifícia Universidade Católica do Paraná, Curitiba, PR (Brazil); Paula, J.B. de [Médico,Doutor em Engenharia Biomédica, Curitiba, PR (Brazil); Moser, A.D.L. [Escola Politécnica, Programa de Pós-Graduação em Tecnologia em Saúde, Pontifícia Universidade Católica do Paraná, Curitiba, PR (Brazil)

    2012-04-05

    Heterotopic ossification (HO) is a metaplastic biological process in which there is newly formed bone in soft tissues adjacent to large joints, resulting in joint mobility deficit. In order to determine which treatment techniques are more appropriate for such condition, experimental models of induced heterotopic bone formation have been proposed using heterologous demineralized bone matrix implants and bone morphogenetic protein and other tissues. The objective of the present experimental study was to identify a reliable protocol to induce HO in Wistar rats, based on autologous bone marrow (BM) implantation, comparing 3 different BM volumes and based on literature evidence of this HO induction model in larger laboratory animals. Twelve male Wistar albino rats weighing 350/390 g were used. The animals were anesthetized for blood sampling before HO induction in order to quantify serum alkaline phosphatase (ALP). HO was induced by BM implantation in both quadriceps muscles of these animals, experimental group (EG). Thirty-five days after the induction, another blood sample was collected for ALP determination. The results showed a weight gain in the EG and no significant difference in ALP levels when comparing the periods before and after induction. Qualitative histological analysis confirmed the occurrence of heterotopic ossification in all 12 EG rats. In conclusion, the HO induction model was effective when 0.35 mL autologous BM was applied to the quadriceps of Wistar rats.

  3. Experimental model of heterotopic ossification in Wistar rats

    International Nuclear Information System (INIS)

    Zotz, T.G.G.; Paula, J.B. de; Moser, A.D.L.

    2012-01-01

    Heterotopic ossification (HO) is a metaplastic biological process in which there is newly formed bone in soft tissues adjacent to large joints, resulting in joint mobility deficit. In order to determine which treatment techniques are more appropriate for such condition, experimental models of induced heterotopic bone formation have been proposed using heterologous demineralized bone matrix implants and bone morphogenetic protein and other tissues. The objective of the present experimental study was to identify a reliable protocol to induce HO in Wistar rats, based on autologous bone marrow (BM) implantation, comparing 3 different BM volumes and based on literature evidence of this HO induction model in larger laboratory animals. Twelve male Wistar albino rats weighing 350/390 g were used. The animals were anesthetized for blood sampling before HO induction in order to quantify serum alkaline phosphatase (ALP). HO was induced by BM implantation in both quadriceps muscles of these animals, experimental group (EG). Thirty-five days after the induction, another blood sample was collected for ALP determination. The results showed a weight gain in the EG and no significant difference in ALP levels when comparing the periods before and after induction. Qualitative histological analysis confirmed the occurrence of heterotopic ossification in all 12 EG rats. In conclusion, the HO induction model was effective when 0.35 mL autologous BM was applied to the quadriceps of Wistar rats

  4. Experimentation and numerical modeling of forging induced bending (FIB) process

    Science.gov (United States)

    Naseem, S.; van den Boogaard, A. H.

    2016-10-01

    Accurate prediction of the final shape using numerical modeling has been a top priority in the field of sheet and bulk forming. Better shape prediction is the result of a better estimation of the physical stress and strain state. For experimental and numerical investigations of such estimations, simple benchmark processes are used. In this paper a benchmark process involving forging (flattening) of sheet metal between punch and die with negative clearance is proposed. The introduced material flow results in bending. Easy measurability of the angle of this bend makes this process suitable for validation purpose. Physical experiments are performed to characterize this bending angle due to flattening. Furthermore a numerical model is developed to capture this phenomenon. The main focus of this paper is the validation of the numerical model in terms of accurate prediction of the physical results.

  5. 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.

  6. Experimentally Induced Mammalian Models of Glaucoma

    Directory of Open Access Journals (Sweden)

    Makoto Ishikawa

    2015-01-01

    Full Text Available A wide variety of animal models have been used to study glaucoma. Although these models provide valuable information about the disease, there is still no ideal model for studying glaucoma due to its complex pathogenesis. Animal models for glaucoma are pivotal for clarifying glaucoma etiology and for developing novel therapeutic strategies to halt disease progression. In this review paper, we summarize some of the major findings obtained in various glaucoma models and examine the strengths and limitations of these models.

  7. Effects of Erdosteine on Experimental Acute Pancreatitis Model.

    Science.gov (United States)

    Karapolat, Banu; Karapolat, Sami; Gurleyik, Emin; Yasar, Mehmet

    2017-10-01

    To create acute pancreatitis condition experimentally in rats using cerulein, and to reveal histopathological effects in pancreatic tissue with erdosteine. An experimental study. Department of General Surgery, Duzce University, Turkey, from June to October 2014. Thirty male Wistar albino rats were divided into three groups. No procedures were applied to Group 1. The rats in Group 2 and Group 3 were injected cerulein, to establish an experimental pancreatitis model and the blood amylase and lipase values were examined. The rats in Group 3 were given 10 mg/kg erdosteine. This treatment was continued for another 2 days and the rats were sacrificed. The pancreatic tissues were examined histopathologically for edema, inflammation, acinar necrosis, fat necrosis, and vacuolization. The lipase and amylase values and the histopathological examination of pancreatic tissues evidenced that the experimental acute pancreatitis model was established and edema, inflammation, acinar necrosis, fat necrosis, and vacuolization were observed in the pancreatic tissues. The statistical results suggest that erdosteine can decrease the edema, inflammation, acinar necrosis, fat necrosis and vacuolization scores in the tissues. The severity of acute pancreatitis, induced by cerulein in rats, is reduced with the use of erdosteine.

  8. CS model coil experimental log book

    Energy Technology Data Exchange (ETDEWEB)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  9. Experimental investigations and modelling of sodium-concrete interaction

    International Nuclear Information System (INIS)

    Schultheiss, G.F.; Deeg, H.J.

    1990-01-01

    The use of sodium as a coolant in liquid metal fast breeder reactors, fusion reactors, and solar plants requires special consideration of its chemical reactivity and related safety problems in the case of sodium leckage. On contact between hot sodium and concrete an interaction takes place resulting in energy release and hydrogen generation, which may contribute to containment loading by pressurization in a hypothetical accident situation. For this reason, sodium-concrete interactions were investigated experimentally and theoretically. The experiments revealed important effects of quartzitic material within the concrete and of the sodium temperature on the interaction mechanisms, the energy release and the consequent hydrogen production. The numerical model shows good agreement with the experimental results. (orig.) [de

  10. Histopathology of experimental myiasis in mice as a result of infestation and experimental implantation of Dermatobia hominis larvae.

    Science.gov (United States)

    Leite, A C R; Nascimento, M F A; Leite, L H R; Leite, V H R

    2011-05-01

    A laboratory model of myiasis as a result of Dermatobia hominis (L.) larvae was developed using mice as hosts. Mice in three groups were each infested with one newly hatched larva and skin biopsies processed for histopathology at 4, 12, and 20 d postinfestation (dpi). Mice in three other groups were each subjected to implantation of one larva collected from an infested (donor) mouse at 4, 12, and 20 dpi. Skin lesions of these receptor mice were then assessed at 10, 14, and 6 d postimplantation (dpimp), respectively. The inflammatory process in infested mice at 4 dpi was discrete, consisting of a thin necrotic layer around the larva, edema, many neutrophils, few eosinophils, mast cells, and proliferation of fibroblasts. At 12 dpi, there was a thicker necrotic layer, edema, many neutrophils and eosinophils, few mast cells, neoformation of capillaries, proliferation of the endothelium and fibroblasts, and early stages of fibrosis. These histopathological characteristics together with fibrosis were observed over a large area of the lesion at 20 dpi. Mice submitted to larval implantations demonstrated similar skin histopathology to that seen in the infested rodents, 10 dpimp corresponding to 12 dpi and 6 or 14 dpimp to 20 dpi. In all mice, the progressive acute inflammatory process followed a sequence linked to factors such as size of larvae and presence of secretory-excretory products. Both infested mice and those implanted experimentally with D. hominis larvae were shown to be suitable models for the study of the parasite-host relationship in this important zoonotic myiasis.

  11. Experimental model of cutaneous radiation injury in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Meirelles, Rafael Panisi de Campos [Universidade Federal de Sao Paulo (EPM/UNIFESP), SP (Brazil). Escola Paulista de Medicina; Hochman, Bernardo [Universidade Federal de Sao Paulo (EPM/UNIFESP), SP (Brazil). Escola Paulista de Medicina. Dept. de Cirurgia; Helene Junior, Americo; Fraga, Murillo Francisco Pires [Faculdade de Ciencias Medicas da Santa Casa de Sao Paulo (FCMSCSP), SP (Brazil). Dept. de Cirurgia. Divisao de Cirurgia Plastica; Lellis, Rute [Faculdade de Ciencias Medicas da Santa Casa de Sao Paulo (FCMSCSP), SP (Brazil). Divisao de Patologia; Ferreira, Lydia Masako, E-mail: rpcmeirelles@yahoo.com.br, E-mail: lydia.dcir@epm.br [Universidade Federal de Sao Paulo (EPM/UNIFESP), SP (Brazil). Escola Paulista de Mediciana. Divisao de Cirugia Plastica

    2013-07-01

    Purpose: to describe an experimental model of cutaneous radiation injury in rabbits. Methods: on this study eight six-month-old New Zealand male rabbits, with an average weight of 2.5kg were used. They were distributed in four groups (n=2 per group). The control group did not receive radiotherapy and the others received one radiotherapy session of 2000, 3000 and 4500 cGy, respectively. Photographic analysis and histopathological evaluation of the irradiated areas were carried out. Results: after 30 days, the animals from the control group had all their hair grown. In spite of that, the animals from group 2000 cGy had a 60-day alopecia and from group 3000 cGy, a 90-day alopecia. After the 30th day, the 3000cGy group demonstrated 90-day cutaneous radiation injuries, graded 3 and 4. One of the animals from group 4500 cGy died on the 7th day with visceral necrosis. The other from the same group had total skin necrosis. A progressive reduction of glands and blood vessels count and an increase on collagen deposition was observed. Conclusion: The proposed experimental model is reproducible. This study suggests that the dosage 4500cGy is excessive and the 3000 cGy is the most effective for this experimental model of cutaneous radiation injury in rabbits. (author)

  12. Experimental model of cutaneous radiation injury in rabbits

    International Nuclear Information System (INIS)

    Meirelles, Rafael Panisi de Campos; Hochman, Bernardo; Helene Junior, Americo; Fraga, Murillo Francisco Pires; Lellis, Rute; Ferreira, Lydia Masako

    2013-01-01

    Purpose: to describe an experimental model of cutaneous radiation injury in rabbits. Methods: on this study eight six-month-old New Zealand male rabbits, with an average weight of 2.5kg were used. They were distributed in four groups (n=2 per group). The control group did not receive radiotherapy and the others received one radiotherapy session of 2000, 3000 and 4500 cGy, respectively. Photographic analysis and histopathological evaluation of the irradiated areas were carried out. Results: after 30 days, the animals from the control group had all their hair grown. In spite of that, the animals from group 2000 cGy had a 60-day alopecia and from group 3000 cGy, a 90-day alopecia. After the 30th day, the 3000cGy group demonstrated 90-day cutaneous radiation injuries, graded 3 and 4. One of the animals from group 4500 cGy died on the 7th day with visceral necrosis. The other from the same group had total skin necrosis. A progressive reduction of glands and blood vessels count and an increase on collagen deposition was observed. Conclusion: The proposed experimental model is reproducible. This study suggests that the dosage 4500cGy is excessive and the 3000 cGy is the most effective for this experimental model of cutaneous radiation injury in rabbits. (author)

  13. Ionospheric topside models compared with experimental electron density profiles

    Directory of Open Access Journals (Sweden)

    S. M. Radicella

    2005-06-01

    Full Text Available Recently an increasing number of topside electron density profiles has been made available to the scientific community on the Internet. These data are important for ionospheric modeling purposes, since the experimental information on the electron density above the ionosphere maximum of ionization is very scarce. The present work compares NeQuick and IRI models with the topside electron density profiles available in the databases of the ISIS2, IK19 and Cosmos 1809 satellites. Experimental electron content from the F2 peak up to satellite height and electron densities at fixed heights above the peak have been compared under a wide range of different conditions. The analysis performed points out the behavior of the models and the improvements needed to be assessed to have a better reproduction of the experimental results. NeQuick topside is a modified Epstein layer, with thickness parameter determined by an empirical relation. It appears that its performance is strongly affected by this parameter, indicating the need for improvements of its formulation. IRI topside is based on Booker's approach to consider two parts with constant height gradients. It appears that this formulation leads to an overestimation of the electron density in the upper part of the profiles, and overestimation of TEC.

  14. An experimental and modeling study of diethyl carbonate oxidation

    KAUST Repository

    Nakamura, Hisashi

    2015-04-01

    Diethyl carbonate (DEC) is an attractive biofuel that can be used to displace petroleum-derived diesel fuel, thereby reducing CO2 and particulate emissions from diesel engines. A better understanding of DEC combustion characteristics is needed to facilitate its use in internal combustion engines. Toward this goal, ignition delay times for DEC were measured at conditions relevant to internal combustion engines using a rapid compression machine (RCM) and a shock tube. The experimental conditions investigated covered a wide range of temperatures (660-1300K), a pressure of 30bar, and equivalence ratios of 0.5, 1.0 and 2.0 in air. To provide further understanding of the intermediates formed in DEC oxidation, species concentrations were measured in a jet-stirred reactor at 10atm over a temperature range of 500-1200K and at equivalence ratios of 0.5, 1.0 and 2.0. These experimental measurements were used to aid the development and validation of a chemical kinetic model for DEC.The experimental results for ignition in the RCM showed near negative temperature coefficient (NTC) behavior. Six-membered alkylperoxy radical (RO˙2) isomerizations are conventionally thought to initiate low-temperature branching reactions responsible for NTC behavior, but DEC has no such possible 6- and 7-membered ring isomerizations. However, its molecular structure allows for 5-, 8- and 9-membered ring RO˙2 isomerizations. To provide accurate rate constants for these ring structures, ab initio computations for RO˙2⇌Q˙OOH isomerization reactions were performed. These new RO˙2 isomerization rate constants have been implemented in a chemical kinetic model for DEC oxidation. The model simulations have been compared with ignition delay times measured in the RCM near the NTC region. Results of the simulation were also compared with experimental results for ignition in the high-temperature region and for species concentrations in the jet-stirred reactor. Chemical kinetic insights into the

  15. Experimental results in nonlinear compensation of a one degree-of-freedom magnetic suspension

    Science.gov (United States)

    Trumper, David L.; Sanders, James C.; Nguyen, Tiep H.; Queen, Michael A.

    1992-01-01

    Nonlinear control techniques are of increasing interest in magnetic bearing applications. A one-degree-of-freedom magnetic suspension system has been constructed to serve as a test system for nonlinear control. The objective of this effort is to build an accurate model for the nonlinear suspension dynamics and to show the advantages of compensating for these nonlinearities by using a nonlinear controller. The results obtained with a nonlinear controller are experimentally demonstrated as superior to those obtained with a linear controller. Specifically, a controller which contains a force-control block yields transient responses which are largely independent of the operating point air gap.

  16. Preliminary Results on the Experimental Investigation of the Structure Functions of Bound Nucleons

    Energy Technology Data Exchange (ETDEWEB)

    Bodek, Arie [Univ. of Rochester, NY (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-08-01

    We present preliminary results on an experimental study of the nuclear modification of the longitudinal ($\\sigma_L$) and transverse ($\\sigma_T$) structure functions of nucleons bound in nuclear targets. The origin of these modifications (commonly referred as as the EMC effect) is not fully understood. Our measurements of R= $\\sigma_L / \\sigma_T$ for nuclei ($R_A$) and for deuterium ($R_D$) indicate that nuclear modifications of the structure functions of bound nucleons are different for the longitudinal and transverse structure functions, and that contrary to expectation from several theoretical models, $R_A< R_D$.

  17. Pneumatic Adaptive Absorber: Mathematical Modelling with Experimental Verification

    Directory of Open Access Journals (Sweden)

    Grzegorz Mikułowski

    2016-01-01

    Full Text Available Many of mechanical energy absorbers utilized in engineering structures are hydraulic dampers, since they are simple and highly efficient and have favourable volume to load capacity ratio. However, there exist fields of applications where a threat of toxic contamination with the hydraulic fluid contents must be avoided, for example, food or pharmacy industries. A solution here can be a Pneumatic Adaptive Absorber (PAA, which is characterized by a high dissipation efficiency and an inactive medium. In order to properly analyse the characteristics of a PAA, an adequate mathematical model is required. This paper proposes a concept for mathematical modelling of a PAA with experimental verification. The PAA is considered as a piston-cylinder device with a controllable valve incorporated inside the piston. The objective of this paper is to describe a thermodynamic model of a double chamber cylinder with gas migration between the inner volumes of the device. The specific situation considered here is that the process cannot be defined as polytropic, characterized by constant in time thermodynamic coefficients. Instead, the coefficients of the proposed model are updated during the analysis. The results of the experimental research reveal that the proposed mathematical model is able to accurately reflect the physical behaviour of the fabricated demonstrator of the shock absorber.

  18. Septic arthritis: immunopathogenesis, experimental models and therapy

    Science.gov (United States)

    2014-01-01

    Septic arthritis is an inflammatory disease of the joints that is started by an infection whose most common agent is Staphylococcus aureus. In this review we discuss some of the most arthritogenic bacterial factors and the contribution of innate and specific immune mechanisms to joint destruction. Special emphasis is given to the induction of experimental arthritis by S. aureus in mice. The improvement of therapy by association of antibiotics with down-modulation of immunity is also included. PMID:24822058

  19. Experimental comparison of models for ultrafast impact ionization is silicon

    DEFF Research Database (Denmark)

    Tarekegne, Abebe Tilahun; Iwaszczuk, Krzysztof; Jepsen, Peter Uhd

    2016-01-01

    We compare experimentally the exponential and quadratic (Keldysh formula) impact ionization models using THz induced impact ionization in silicon. We demonstrate that the exponential model offers the best description of impact ionization process for ultrashort electric filed pulses....

  20. VX hydrolysis by human serum paraoxonase 1: a comparison of experimental and computational results.

    Directory of Open Access Journals (Sweden)

    Matthew W Peterson

    Full Text Available Human Serum paraoxonase 1 (HuPON1 is an enzyme that has been shown to hydrolyze a variety of chemicals including the nerve agent VX. While wildtype HuPON1 does not exhibit sufficient activity against VX to be used as an in vivo countermeasure, it has been suggested that increasing HuPON1's organophosphorous hydrolase activity by one or two orders of magnitude would make the enzyme suitable for this purpose. The binding interaction between HuPON1 and VX has recently been modeled, but the mechanism for VX hydrolysis is still unknown. In this study, we created a transition state model for VX hydrolysis (VX(ts in water using quantum mechanical/molecular mechanical simulations, and docked the transition state model to 22 experimentally characterized HuPON1 variants using AutoDock Vina. The HuPON1-VX(ts complexes were grouped by reaction mechanism using a novel clustering procedure. The average Vina interaction energies for different clusters were compared to the experimentally determined activities of HuPON1 variants to determine which computational procedures best predict how well HuPON1 variants will hydrolyze VX. The analysis showed that only conformations which have the attacking hydroxyl group of VX(ts coordinated by the sidechain oxygen of D269 have a significant correlation with experimental results. The results from this study can be used for further characterization of how HuPON1 hydrolyzes VX and design of HuPON1 variants with increased activity against VX.

  1. Experimentally driven atomistic model of 1,2 polybutadiene

    Energy Technology Data Exchange (ETDEWEB)

    Gkourmpis, Thomas, E-mail: thomas.gkourmpis@borealisgroup.com [Polymer Science Centre, J. J. Thomson Physical Laboratory, Department of Physics, University of Reading, Reading RG6 6AF (United Kingdom); Mitchell, Geoffrey R. [Polymer Science Centre, J. J. Thomson Physical Laboratory, Department of Physics, University of Reading, Reading RG6 6AF (United Kingdom); Centre for Rapid and Sustainable Product Development, Institute Polytechnic Leiria, Marinha Grande (Portugal)

    2014-02-07

    We present an efficient method of combining wide angle neutron scattering data with detailed atomistic models, allowing us to perform a quantitative and qualitative mapping of the organisation of the chain conformation in both glass and liquid phases. The structural refinement method presented in this work is based on the exploitation of the intrachain features of the diffraction pattern and its intimate linkage with atomistic models by the use of internal coordinates for bond lengths, valence angles, and torsion rotations. Atomic connectivity is defined through these coordinates that are in turn assigned by pre-defined probability distributions, thus allowing for the models in question to be built stochastically. Incremental variation of these coordinates allows for the construction of models that minimise the differences between the observed and calculated structure factors. We present a series of neutron scattering data of 1,2 polybutadiene at the region 120–400 K. Analysis of the experimental data yields bond lengths for Cî—¸C and C î—» C of 1.54 Å and 1.35 Å, respectively. Valence angles of the backbone were found to be at 112° and the torsion distributions are characterised by five rotational states, a three-fold trans-skew± for the backbone and gauche± for the vinyl group. Rotational states of the vinyl group were found to be equally populated, indicating a largely atactic chan. The two backbone torsion angles exhibit different behaviour with respect to temperature of their trans population, with one of them adopting an almost all trans sequence. Consequently, the resulting configuration leads to a rather persistent chain, something indicated by the value of the characteristic ratio extrapolated from the model. We compare our results with theoretical predictions, computer simulations, RIS models and previously reported experimental results.

  2. Short note: the experimental geopotential model XGM2016

    Science.gov (United States)

    Pail, R.; Fecher, T.; Barnes, D.; Factor, J. F.; Holmes, S. A.; Gruber, T.; Zingerle, P.

    2018-04-01

    As a precursor study for the upcoming combined Earth Gravitational Model 2020 (EGM2020), the Experimental Gravity Field Model XGM2016, parameterized as a spherical harmonic series up to degree and order 719, is computed. XGM2016 shares the same combination methodology as its predecessor model GOCO05c (Fecher et al. in Surv Geophys 38(3): 571-590, 2017. doi: 10.1007/s10712-016-9406-y). The main difference between these models is that XGM2016 is supported by an improved terrestrial data set of 15^' × 15^' gravity anomaly area-means provided by the United States National Geospatial-Intelligence Agency (NGA), resulting in significant upgrades compared to existing combined gravity field models, especially in continental areas such as South America, Africa, parts of Asia, and Antarctica. A combination strategy of relative regional weighting provides for improved performance in near-coastal ocean regions, including regions where the altimetric data are mostly unchanged from previous models. Comparing cumulative height anomalies, from both EGM2008 and XGM2016 at degree/order 719, yields differences of 26 cm in Africa and 40 cm in South America. These differences result from including additional information of satellite data, as well as from the improved ground data in these regions. XGM2016 also yields a smoother Mean Dynamic Topography with significantly reduced artifacts, which indicates an improved modeling of the ocean areas.

  3. Short note: the experimental geopotential model XGM2016

    Science.gov (United States)

    Pail, R.; Fecher, T.; Barnes, D.; Factor, J. F.; Holmes, S. A.; Gruber, T.; Zingerle, P.

    2017-10-01

    As a precursor study for the upcoming combined Earth Gravitational Model 2020 (EGM2020), the Experimental Gravity Field Model XGM2016, parameterized as a spherical harmonic series up to degree and order 719, is computed. XGM2016 shares the same combination methodology as its predecessor model GOCO05c (Fecher et al. in Surv Geophys 38(3): 571-590, 2017. doi: 10.1007/s10712-016-9406-y). The main difference between these models is that XGM2016 is supported by an improved terrestrial data set of 15^' × 15^' gravity anomaly area-means provided by the United States National Geospatial-Intelligence Agency (NGA), resulting in significant upgrades compared to existing combined gravity field models, especially in continental areas such as South America, Africa, parts of Asia, and Antarctica. A combination strategy of relative regional weighting provides for improved performance in near-coastal ocean regions, including regions where the altimetric data are mostly unchanged from previous models. Comparing cumulative height anomalies, from both EGM2008 and XGM2016 at degree/order 719, yields differences of 26 cm in Africa and 40 cm in South America. These differences result from including additional information of satellite data, as well as from the improved ground data in these regions. XGM2016 also yields a smoother Mean Dynamic Topography with significantly reduced artifacts, which indicates an improved modeling of the ocean areas.

  4. Experimental validation of solid rocket motor damping models

    Science.gov (United States)

    Riso, Cristina; Fransen, Sebastiaan; Mastroddi, Franco; Coppotelli, Giuliano; Trequattrini, Francesco; De Vivo, Alessio

    2017-12-01

    In design and certification of spacecraft, payload/launcher coupled load analyses are performed to simulate the satellite dynamic environment. To obtain accurate predictions, the system damping properties must be properly taken into account in the finite element model used for coupled load analysis. This is typically done using a structural damping characterization in the frequency domain, which is not applicable in the time domain. Therefore, the structural damping matrix of the system must be converted into an equivalent viscous damping matrix when a transient coupled load analysis is performed. This paper focuses on the validation of equivalent viscous damping methods for dynamically condensed finite element models via correlation with experimental data for a realistic structure representative of a slender launch vehicle with solid rocket motors. A second scope of the paper is to investigate how to conveniently choose a single combination of Young's modulus and structural damping coefficient—complex Young's modulus—to approximate the viscoelastic behavior of a solid propellant material in the frequency band of interest for coupled load analysis. A scaled-down test article inspired to the Z9-ignition Vega launcher configuration is designed, manufactured, and experimentally tested to obtain data for validation of the equivalent viscous damping methods. The Z9-like component of the test article is filled with a viscoelastic material representative of the Z9 solid propellant that is also preliminarily tested to investigate the dependency of the complex Young's modulus on the excitation frequency and provide data for the test article finite element model. Experimental results from seismic and shock tests performed on the test configuration are correlated with numerical results from frequency and time domain analyses carried out on its dynamically condensed finite element model to assess the applicability of different equivalent viscous damping methods to describe

  5. Analytical modelling and experimental studies of SIS tunnel solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Cheknane, Ali [Laboratoire de Valorisation des Energies Renouvelables et Environnements Agressifs, Universite Amar Telidji de Laghouat, BP 37G route de Ghardaia, Laghouat (03000) Algerie (Algeria)], E-mail: cheknanali@yahoo.com

    2009-06-07

    This paper presents an experimental and computational study of semiconductor-insulator-semiconductor (SIS) tunnel solar cells. A transparent and conductive film of thallium trioxide Tl{sub 2}O{sub 3} has been deposited by anodic oxidation onto an n-Si(1 0 0) face to realize the SIS tunnel solar cells based on Si/SiO{sub x}/Tl{sub 2}O{sub 3}. An efficiency of 8.77% has been obtained under an incident power density of 33 mW cm{sup -2} illumination condition. A PSPICE model is implemented. The calculated results show that the theoretical values are in good agreement with experimental data. Moreover, the simulation clearly demonstrates that the performance of the tested device can be significantly improved.

  6. Improving the physiological realism of experimental models

    NARCIS (Netherlands)

    Vinnakota, Kalyan C.; Cha, Chae Y.; Rorsman, Patrik; Balaban, Robert S.; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A.; Jeneson, Jeroen A. L.

    The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these

  7. Results of steel containment vessel model test

    International Nuclear Information System (INIS)

    Luk, V.K.; Ludwigsen, J.S.; Hessheimer, M.F.; Komine, Kuniaki; Matsumoto, Tomoyuki; Costello, J.F.

    1998-05-01

    A series of static overpressurization tests of scale models of nuclear containment structures is being conducted by Sandia National Laboratories for the Nuclear Power Engineering Corporation of Japan and the US Nuclear Regulatory Commission. Two tests are being conducted: (1) a test of a model of a steel containment vessel (SCV) and (2) a test of a model of a prestressed concrete containment vessel (PCCV). This paper summarizes the conduct of the high pressure pneumatic test of the SCV model and the results of that test. Results of this test are summarized and are compared with pretest predictions performed by the sponsoring organizations and others who participated in a blind pretest prediction effort. Questions raised by this comparison are identified and plans for posttest analysis are discussed

  8. Use of linear programming models in experimentation with plant nutrients

    Directory of Open Access Journals (Sweden)

    Mauro Brino Garcia

    2013-06-01

    Full Text Available Nutrition is an important issue of plant cultivation and experimentation with plant nutrients is a supporting tool for agriculture. However, use of high purity grade reagents as nutrient sources can be expensive and increases the cost of an experiment. The objective of this study was to minimize the acquisition cost of high purity grade reagents in experiments on plant nutrient deficiency by using the missing element technique through linear programming models, and to generate recommendation tables for preparation of culture solutions, as well as to quantify gains through a simulated experiment. Two linear programming models were formulated containing concentration constraints for each nutrient in the culture solution. Model A was based on 16 reagents for preparation of the culture solution, while model B was based on 27 reagents, looking to increase choice options. Results showed that both models minimized the acquisition cost of reagents, allowing a 9.03% reduction in model A and a 25.98% reduction in model B. The missing sulfur treatment proved the most costly for reagent acquisition while the missing nitrogen treatment proved the least costly. It was concluded that the formulated models were capable of reducing acquisition costs of reagents, yet the recommendations generated by them should be tested and checked for practical viability.

  9. Hydroforming Of Patchwork Blanks — Numerical Modeling And Experimental Validation

    Science.gov (United States)

    Lamprecht, Klaus; Merklein, Marion; Geiger, Manfred

    2005-08-01

    In comparison to the commonly applied technology of tailored blanks the concept of patchwork blanks offers a number of additional advantages. Potential application areas for patchwork blanks in automotive industry are e.g. local reinforcements of automotive closures, structural reinforcements of rails and pillars as well as shock towers. But even if there is a significant application potential for patchwork blanks in automobile production, industrial realization of this innovative technique is decelerated due to a lack of knowledge regarding the forming behavior and the numerical modeling of patchwork blanks. Especially for the numerical simulation of hydroforming processes, where one part of the forming tool is replaced by a fluid under pressure, advanced modeling techniques are required to ensure an accurate prediction of the blanks' forming behavior. The objective of this contribution is to provide an appropriate model for the numerical simulation of patchwork blanks' forming processes. Therefore, different finite element modeling techniques for patchwork blanks are presented. In addition to basic shell element models a combined finite element model consisting of shell and solid elements is defined. Special emphasis is placed on the modeling of the weld seam. For this purpose the local mechanical properties of the weld metal, which have been determined by means of Martens-hardness measurements and uniaxial tensile tests, are integrated in the finite element models. The results obtained from the numerical simulations are compared to experimental data from a hydraulic bulge test. In this context the focus is laid on laser- and spot-welded patchwork blanks.

  10. Experimental validation of Swy-2 clay standard's PHREEQC model

    Science.gov (United States)

    Szabó, Zsuzsanna; Hegyfalvi, Csaba; Freiler, Ágnes; Udvardi, Beatrix; Kónya, Péter; Székely, Edit; Falus, György

    2017-04-01

    One of the challenges of the present century is to limit the greenhouse gas emissions for the mitigation of climate change which is possible for example by a transitional technology, CCS (Carbon Capture and Storage) and, among others, by the increase of nuclear proportion in the energy mix. Clay minerals are considered to be responsible for the low permeability and sealing capacity of caprocks sealing off stored CO2 and they are also the main constituents of bentonite in high level radioactive waste disposal facilities. The understanding of clay behaviour in these deep geological environments is possible through laboratory batch experiments of well-known standards and coupled geochemical models. Such experimentally validated models are scarce even though they allow deriving more precise long-term predictions of mineral reactions and rock and bentonite degradation underground and, therefore, ensuring the safety of the above technologies and increase their public acceptance. This ongoing work aims to create a kinetic geochemical model of Na-montmorillonite standard Swy-2 in the widely used PHREEQC code, supported by solution and mineral composition results from batch experiments. Several four days experiments have been carried out in 1:35 rock:water ratio at atmospheric conditions, and with inert and CO2 supercritical phase at 100 bar and 80 ⁰C relevant for the potential Hungarian CO2 reservoir complex. Solution samples have been taken during and after experiments and their compositions were measured by ICP-OES. The treated solid phase has been analysed by XRD and ATR-FTIR and compared to in-parallel measured references (dried Swy-2). Kinetic geochemical modelling of the experimental conditions has been performed by PHREEQC version 3 using equations and kinetic rate parameters from the USGS report of Palandri and Kharaka (2004). The visualization of experimental and numerous modelling results has been automatized by R. Experiments and models show very fast

  11. Determination of solubility profiles of eflucimibe polymorphs: experimental and modeling.

    Science.gov (United States)

    Teychene, S; Autret, J M; Biscans, B

    2006-04-01

    This work presents the determination of the phase diagram of two polymorphs of Eflucimibe in pure solvents and solvent mixtures at different temperatures. Solid phase changes were analysed by Differential Scanning Calorimetry. Solubility measurements show that the solubility of the two forms are very similar. Experimental data obtained in ethanol, reported in a Van t'Hoff plot, exhibit a transition temperature around 265 K. A single maximum is observed when solubility is plotted against the solubility parameters of solvents or solvent mixture and it is not related to a solid phase change. This phenomenon, known as a positive synergetic effect, has been explained in term of evolution of solute-solvents polar interactions. Several thermodynamics models (UNIFAC, UNIQUAC, Wilson, Scatchard Hildebrand ... ) were tested in order to predict the Liquid-Solid Equilibrium for this system. The semi empirical model UNIQUAC gives the best fit. The results obtained are in good agreement with the experimental data (mean deviation lower than 5%) and the solubility maximum found experimentally for each polymorph is also well described.

  12. DMFC anode polarization: Experimental analysis and model validation

    Science.gov (United States)

    Casalegno, A.; Marchesi, R.

    Anode two-phase flow has an important influence on DMFC performance and methanol crossover. In order to elucidate two-phase flow influence on anode performance, in this work, anode polarization is investigated combining experimental and modelling approach. A systematic experimental analysis of operating conditions influence on anode polarization is presented. Hysteresis due to operating condition is observed; experimental results suggest that it arises from methanol accumulation and has to be considered in evaluating DMFC performances and measurements reproducibility. A model of DMFC anode polarization is presented and utilised as tool to investigate anode two-phase flow. The proposed analysis permits one to produce a confident interpretation of the main involved phenomena. In particular, it confirms that methanol electro-oxidation kinetics is weakly dependent on methanol concentration and that methanol transport in gas phase produces an important contribution in anode feeding. Moreover, it emphasises the possibility to optimise anode flow rate in order to improve DMFC performance and reduce methanol crossover.

  13. Comparison of mixed layer models predictions with experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Faggian, P.; Riva, G.M. [CISE Spa, Divisione Ambiente, Segrate (Italy); Brusasca, G. [ENEL Spa, CRAM, Milano (Italy)

    1997-10-01

    The temporal evolution of the PBL vertical structure for a North Italian rural site, situated within relatively large agricultural fields and almost flat terrain, has been investigated during the period 22-28 June 1993 by experimental and modellistic point of view. In particular, the results about a sunny day (June 22) and a cloudy day (June 25) are presented in this paper. Three schemes to estimate mixing layer depth have been compared, i.e. Holzworth (1967), Carson (1973) and Gryning-Batchvarova models (1990), which use standard meteorological observations. To estimate their degree of accuracy, model outputs were analyzed considering radio-sounding meteorological profiles and stability atmospheric classification criteria. Besides, the mixed layer depths prediction were compared with the estimated values obtained by a simple box model, whose input requires hourly measures of air concentrations and ground flux of {sup 222}Rn. (LN)

  14. 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.

  15. A physiological production model for cacao : results of model simulations

    NARCIS (Netherlands)

    Zuidema, P.A.; Leffelaar, P.A.

    2002-01-01

    CASE2 is a physiological model for cocoa (Theobroma cacao L.) growth and yield. This report introduces the CAcao Simulation Engine for water-limited production in a non-technical way and presents simulation results obtained with the model.

  16. Experimental animal model for late postradiation reaction of the colon

    International Nuclear Information System (INIS)

    Trott, K.R.

    1987-01-01

    Experimental animal model worked out in Muenchen is discussed in which late postradiation reaction in Wistar rats following local irradiation of the colon manifests itself by appearance of colonic stenoses causing death of the animal. Clinical symptoms of this reaction together with results of histopathologic examination of the excised parts of the colon localized in the irradiated area are discussed. The relationships effect-dose obtained in this system for X radiation applying different regimen of dose fractionation and different total times of irradiation are presented. 8 refs., 5 figs., 1 tab. (author)

  17. Optimization of experimental human leukemia models (review

    Directory of Open Access Journals (Sweden)

    D. D. Pankov

    2012-01-01

    Full Text Available Actual problem of assessing immunotherapy prospects including antigenpecific cell therapy using animal models was covered in this review.Describe the various groups of currently existing animal models and methods of their creating – from different immunodeficient mice to severalvariants of tumor cells engraftment in them. The review addresses the possibility of tumor stem cells studying using mouse models for the leukemia treatment with adoptive cell therapy including WT1. Also issues of human leukemia cells migration and proliferation in a mice withdifferent immunodeficiency degree are discussed. To assess the potential immunotherapy efficacy comparison of immunodeficient mouse model with clinical situation in oncology patients after chemotherapy is proposed.

  18. Ideal Experimental Rat Models for Liver Diseases

    OpenAIRE

    Lee, Sang Woo; Kim, Sung Hoon; Min, Seon Ok; Kim, Kyung Sik

    2011-01-01

    There are many limitations for conducting liver disease research in human beings due to the high cost and potential ethical issues. For this reason, conducting a study that is difficult to perform in humans using appropriate animal models, can be beneficial in ascertaining the pathological physiology, and in developing new treatment modalities. However, it is difficult to determine the appropriate animal model which is suitable for research purposes, since every patient has different and dive...

  19. Performance of strength mis-match welded joints: Comparison of experimental and numerical results

    International Nuclear Information System (INIS)

    Hornet, P.; Eripret, Ch.; Kocak, M.; Junghans, E.

    1997-01-01

    It is known that the fracture behaviour of a welded structure with a weld metal or Heat Affected Zone (HAZ) crack is influenced by the mechanical properties of the neighbouring regions (weld metal, base metal and heat affected zone) the ligament size and the weld dimensions. In order to better understand those phenomena, a research programme using both numerical and experimental approaches has been conducted at EDF and GKSS research centres. Two 70 mm thick 316L austenitic stainless steel plates have been butt-welded using a TIG welding process. The weld metal yield strength is more than twice the base metal yield strength. From this overmatched weld, 25 mm thick Compact Tension, Single Edge Notched Bend and Center Cracked panels in Tension, specimens (a/W=0.5) have been prepared and tested at room temperature. The crack was located in the middle of the weld metal. Those experiments have been modeled by 3D finite element calculations using the Aster code developed at EDF/RSDD. This paper presents the comparison between the experimental and the numerical results in terms of load line displacement, crack mouth opening displacement and crack tip opening displacement measured experimentally using the δ-clip developed at GKSS. Moreover resistance curves determined on those various specimens are also compared, so as to investigate any geometry effect. (authors)

  20. An experimental comparison of modelling techniques for speaker ...

    Indian Academy of Sciences (India)

    Most of the existing modelling techniques for the speaker recognition task make an implicit assumption of sufficient data for speaker modelling and hence may lead to poor modelling under limited data condition. The present work gives an experimental evaluation of the modelling techniques like Crisp Vector Quantization ...

  1. An experimental comparison of modelling techniques for speaker ...

    Indian Academy of Sciences (India)

    Abstract. Most of the existing modelling techniques for the speaker recog- nition task make an implicit assumption of sufficient data for speaker modelling and hence may lead to poor modelling under limited data condition. The present work gives an experimental evaluation of the modelling techniques like Crisp.

  2. Interpreting Results from the Multinomial Logit Model

    DEFF Research Database (Denmark)

    Wulff, Jesper

    2015-01-01

    This article provides guidelines and illustrates practical steps necessary for an analysis of results from the multinomial logit model (MLM). The MLM is a popular model in the strategy literature because it allows researchers to examine strategic choices with multiple outcomes. However, there seem...... to be systematic issues with regard to how researchers interpret their results when using the MLM. In this study, I present a set of guidelines critical to analyzing and interpreting results from the MLM. The procedure involves intuitive graphical representations of predicted probabilities and marginal effects...... suitable for both interpretation and communication of results. The pratical steps are illustrated through an application of the MLM to the choice of foreign market entry mode....

  3. Ideal Experimental Rat Models for Liver Diseases.

    Science.gov (United States)

    Lee, Sang Woo; Kim, Sung Hoon; Min, Seon Ok; Kim, Kyung Sik

    2011-05-01

    There are many limitations for conducting liver disease research in human beings due to the high cost and potential ethical issues. For this reason, conducting a study that is difficult to perform in humans using appropriate animal models, can be beneficial in ascertaining the pathological physiology, and in developing new treatment modalities. However, it is difficult to determine the appropriate animal model which is suitable for research purposes, since every patient has different and diverse clinical symptoms, adverse reactions, and complications due to the pathological physiology. Also, it is not easy to reproduce identically various clinical situations in animal models. Recently, the Guide for the Care and Use of Laboratory Animals has tightened up the regulations, and therefore it is advisable to select the appropriate animals and decide upon the appropriate quantities through scientific and systemic considerations before conducting animal testing. Therefore, in this review article the authors examined various white rat animal testing models and determined the appropriate usable rat model, and the pros and cons of its application in liver disease research. The authors believe that this review will be beneficial in selecting proper laboratory animals for research purposes.

  4. Power-Based Setpoint Control : Experimental Results on a Planar Manipulator

    NARCIS (Netherlands)

    Dirksz, D. A.; Scherpen, J. M. A.

    In the last years the power-based modeling framework, developed in the sixties to model nonlinear electrical RLC networks, has been extended for modeling and control of a larger class of physical systems. In this brief we apply power-based integral control to a planar manipulator experimental setup.

  5. A new dietary model to study colorectal carcinogenesis: experimental design, food preparation, and experimental findings.

    Science.gov (United States)

    Rozen, P; Liberman, V; Lubin, F; Angel, S; Owen, R; Trostler, N; Shkolnik, T; Kritchevsky, D

    1996-01-01

    Experimental dietary studies of human colorectal carcinogenesis are usually based on the AIN-76A diet, which is dissimilar to human food in source, preparation, and content. The aims of this study were to examine the feasibility of preparing and feeding rats the diet of a specific human population at risk for colorectal neoplasia and to determine whether changes in the colonic morphology and metabolic contents would differ from those resulting from a standard rat diet. The mean daily food intake composition of a previously evaluated adenoma patient case-control study was used for the "human adenoma" (HA) experimental diet. Foods were prepared as for usual human consumption and processed by dehydration to the physical characteristics of an animal diet. Sixty-four female Sprague-Dawley rats were randomized and fed ad libitum the HA or the AIN-76A diet. Every eight weeks, eight rats from each group were sacrificed, and the colons and contents were examined. Analysis of the prepared food showed no significant deleterious changes; food intake and weight gain were similar in both groups. Compared with the controls, the colonic contents of rats fed the HA diet contained significantly less calcium, concentrations of neutral sterols, total lipids, and cholic and deoxycholic acids were increased, and there were no colonic histological changes other than significant epithelial hyperproliferation. This initial study demonstrated that the HA diet can be successfully processed for feeding to experimental animals and is acceptable and adequate for growth but induces significant metabolic and hyperproliferative changes in the rat colon. This dietary model may be useful for studies of human food, narrowing the gap between animal experimentation and human nutritional research.

  6. Scaled Experimental Modeling of VHTR Plenum Flows

    International Nuclear Information System (INIS)

    ICONE, 15

    2007-01-01

    The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. which has the goal of demonstrating the production of emissions free electricity and hydrogen by 2015. Various scaled heated gas and water flow facilities were investigated for modeling VHTR upper and lower plenum flows during the decay heat portion of a pressurized conduction-cooldown scenario and for modeling thermal mixing and stratification (''thermal striping'') in the lower plenum during normal operation. It was concluded, based on phenomena scaling and instrumentation and other practical considerations, that a heated water flow scale model facility is preferable to a heated gas flow facility and to unheated facilities which use fluids with ranges of density to simulate the density effect of heating. For a heated water flow lower plenum model, both the Richardson numbers and Reynolds numbers may be approximately matched for conduction-cooldown natural circulation conditions. Thermal mixing during normal operation may be simulated but at lower, but still fully turbulent, Reynolds numbers than in the prototype. Natural circulation flows in the upper plenum may also be simulated in a separate heated water flow facility that uses the same plumbing as the lower plenum model. However, Reynolds number scaling distortions will occur at matching Richardson numbers due primarily to the necessity of using a reduced number of channels connected to the plenum than in the prototype (which has approximately 11,000 core channels connected to the upper plenum) in an otherwise geometrically scaled model. Experiments conducted in either or both facilities will meet the objectives of providing benchmark data for the validation of codes proposed for NGNP designs and safety studies, as well as providing a better understanding of the complex flow phenomena in the plenums

  7. Scaled experimental modeling of VHTR plenum flows

    International Nuclear Information System (INIS)

    McCreery, Glenn E.; Condie, Keith G.; Schultz, Richard R.

    2007-01-01

    The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. Various scaled heated and unheated gas and water flow facilities were investigated for modeling VHTR upper and lower plenum flows during the decay heat portion of a pressurized conduction-cooldown scenario and for modeling thermal mixing and stratification ('thermal striping') in the lower plenum during normal operation. It was concluded, based on phenomena scaling and instrumentation and other practical considerations, that a heated water flow scale model facility is preferable to a heated gas flow facility and to unheated facilities which use fluids with ranges of density to simulate the buoyancy effect of heating. For a heated water flow lower plenum model, both the Richardson numbers and Reynolds numbers may be approximately matched for conduction-cooldown natural circulation conditions. Thermal mixing during normal operation may be simulated but at lower, but still fully turbulent, Reynolds numbers than in the prototype. Natural circulation flows in the upper plenum may also be simulated in a separate heated water flow facility that uses the same plumbing as the lower plenum model. However, scaling distortions will occur due primarily to the necessity of using a reduced number of channels connected to the upper plenum than in the prototype in an otherwise geometrically scaled model. Experiments conducted in either or both facilities will meet the objectives of providing benchmark data for the validation of codes proposed for NGNP designs and safety studies, as well as providing a better understanding of the complex flow phenomena in the plenums. (author)

  8. Scaled Experimental Modeling of VHTR Plenum Flows

    Energy Technology Data Exchange (ETDEWEB)

    ICONE 15

    2007-04-01

    Abstract The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. which has the goal of demonstrating the production of emissions free electricity and hydrogen by 2015. Various scaled heated gas and water flow facilities were investigated for modeling VHTR upper and lower plenum flows during the decay heat portion of a pressurized conduction-cooldown scenario and for modeling thermal mixing and stratification (“thermal striping”) in the lower plenum during normal operation. It was concluded, based on phenomena scaling and instrumentation and other practical considerations, that a heated water flow scale model facility is preferable to a heated gas flow facility and to unheated facilities which use fluids with ranges of density to simulate the density effect of heating. For a heated water flow lower plenum model, both the Richardson numbers and Reynolds numbers may be approximately matched for conduction-cooldown natural circulation conditions. Thermal mixing during normal operation may be simulated but at lower, but still fully turbulent, Reynolds numbers than in the prototype. Natural circulation flows in the upper plenum may also be simulated in a separate heated water flow facility that uses the same plumbing as the lower plenum model. However, Reynolds number scaling distortions will occur at matching Richardson numbers due primarily to the necessity of using a reduced number of channels connected to the plenum than in the prototype (which has approximately 11,000 core channels connected to the upper plenum) in an otherwise geometrically scaled model. Experiments conducted in either or both facilities will meet the objectives of providing benchmark data for the validation of codes proposed for NGNP designs and safety studies, as well as providing a better understanding of the complex flow phenomena in the plenums.

  9. Efficient experimental designs for sigmoidal growth models

    OpenAIRE

    Dette, Holger; Pepelyshev, Andrey

    2005-01-01

    For the Weibull- and Richards-regression model robust designs are determined by maximizing a minimum of D- or D1-efficiencies, taken over a certain range of the non-linear parameters. It is demonstrated that the derived designs yield a satisfactory solution of the optimal design problem for this type of model in the sense that these designs are efficient and robust with respect to misspecification of the unknown parameters. Moreover, the designs can also be used for testing the postulated for...

  10. Experimental and modelling studies of infiltration

    International Nuclear Information System (INIS)

    Giudici, M.

    2004-01-01

    This presentation describes a study of infiltration in the unsaturated soil with the objective of estimating the recharge to a phreatic aquifer. The study area is at the border of the city of Milan (Northern Italy), which draws water for both domestic and industrial purposes from ground water resources located beneath the urban area. The rate of water pumping from the aquifer system has been varying during the XX century, depending upon the number of inhabitants and the development of industrial activities. This caused variations with time of the depth of the water table below the ground surface and in turn some emergencies: the two most prominent episodes correspond to the middle '70s, when the water table in the city centre was about 30 m below the undisturbed natural conditions, and to the last decade, when the water table has raised at a rate of approximately 1 m/year and caused infiltrations in deep constructions (garages and building foundations, the underground railways, etc.). We have developed four ground water flow models at different scales, which share some characteristics: they are based on quasi-3D approximation (horizontal flow in the aquifers and vertical flow in the aquitards), conservative finite-differences schemes for regular grid with square cells in the horizontal plane and are implemented with proprietary computer codes. Among the problems that were studied for the development of these models, I recall some numerical problems, related to the behaviour of the phreatic aquifer under conditions of strong exploitation. Model calibration and validation for ModMil has been performed with a two-stage process, i.e., using some of the available data for model calibration and the remaining data for model validation. The application of geophysical exploration techniques, in particular seismic and geo-electrical prospecting, has been very useful to complete the data and information on the hydro-geological structure obtained from stratigraphic logs

  11. Experimental geothermal well at Bad Schinznach. First results; Geothermiebohrung Bad Schinznach. Erste Resultate

    Energy Technology Data Exchange (ETDEWEB)

    Haering, M.O. [Haering Geo-Project, Steinmaur (Switzerland)

    1997-12-01

    The spa of Bad Schinznach (Canton Argovia, Switzerland) endeavours to cover its heating requirements with geothermal energy. A recently drilled well to a depth of 890 meters encountered the regional acquifer of thermal water (Oberer Muschelkalk, Triassic) in three levels. Preliminary results indicate a productive aquifer in the uppermost level with a wellhead temperature of 42 C. An additional exploitation of the bottomhole formation temperature of 63 C is envisaged. (orig.) [Deutsch] Das Bad Schinznach (Kanton Aargau, Schweiz) moechte im Rahmen der wirtschaftlichen Moeglichkeiten seinen Waermebedarf mit der Nutzung des Thermalwassers aus dem Oberen Muschelkalk (Trias) decken. Eine neulich abgeteufte Bohrung bis auf 890 Meter Tiefe hat die Formation auf drei Niveaus angetroffen. Erste Resultate deuten auf ein nutzbares Vorkommen im obersten Horizont mit einer Austrittstemperatur von 42 C. Eine zusaetzliche Nutzung der hohen Formationstemperatur von 63 C auf Endtiefe wird erwogen. (orig.)

  12. Passive Nosetip Technology (PANT) Program. Volume X. Summary of Experimental and Analytical Results

    Science.gov (United States)

    1975-01-01

    Wool, 4. R., Powers , C. A., and Derbidge, T. C., "Passive Nosetip Technology (PANT), Interim Report, Volume V - Definition of Shape Change from Low ...techniques are being developed. Model preheating and model recovery techniques are also being developed. High power (50 MIW) arcjets provide simulation...Phenomenology from Low Tempera- ture Ablator Experiments Part I - Experimental Data, Series C (Preliminary Test Series) Part II - Experimental Data

  13. Isothermal coarse mixing: experimental and CFD modelling

    International Nuclear Information System (INIS)

    Gilbertson, M.A.; Kenning, D.B.R.; Hall, R.W.

    1992-01-01

    A plane, two-dimensional flow apparatus has been built which uses a jet of solid 6mm diameter balls to model a jet of molten drops falling into a tank of water to study premixing prior to a vapour explosion. Preliminary experiments with unheated stainless steel balls are here compared with computational fluid dynamics (CFD) calculations by the code CHYMES. (6 figures) (Author)

  14. New experimental model of multiple myeloma.

    Science.gov (United States)

    Telegin, G B; Kalinina, A R; Ponomarenko, N A; Ovsepyan, A A; Smirnov, S V; Tsybenko, V V; Homeriki, S G

    2001-06-01

    NSO/1 (P3x63Ay 8Ut) and SP20 myeloma cells were inoculated to BALB/c OlaHsd mice. NSO/1 cells allowed adequate stage-by-stage monitoring of tumor development. The adequacy of this model was confirmed in experiments with conventional cytostatics: prospidium and cytarabine caused necrosis of tumor cells and reduced animal mortality.

  15. 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...

  16. Neuroinflammatory targets and treatments for epilepsy validated in experimental models.

    Science.gov (United States)

    Aronica, Eleonora; Bauer, Sebastian; Bozzi, Yuri; Caleo, Matteo; Dingledine, Raymond; Gorter, Jan A; Henshall, David C; Kaufer, Daniela; Koh, Sookyong; Löscher, Wolfgang; Louboutin, Jean-Pierre; Mishto, Michele; Norwood, Braxton A; Palma, Eleonora; Poulter, Michael O; Terrone, Gaetano; Vezzani, Annamaria; Kaminski, Rafal M

    2017-07-01

    A large body of evidence that has accumulated over the past decade strongly supports the role of inflammation in the pathophysiology of human epilepsy. Specific inflammatory molecules and pathways have been identified that influence various pathologic outcomes in different experimental models of epilepsy. Most importantly, the same inflammatory pathways have also been found in surgically resected brain tissue from patients with treatment-resistant epilepsy. New antiseizure therapies may be derived from these novel potential targets. An essential and crucial question is whether targeting these molecules and pathways may result in anti-ictogenesis, antiepileptogenesis, and/or disease-modification effects. Therefore, preclinical testing in models mimicking relevant aspects of epileptogenesis is needed to guide integrated experimental and clinical trial designs. We discuss the most recent preclinical proof-of-concept studies validating a number of therapeutic approaches against inflammatory mechanisms in animal models that could represent novel avenues for drug development in epilepsy. Finally, we suggest future directions to accelerate preclinical to clinical translation of these recent discoveries. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  17. Wave Synchronizing Crane Control during Water Entry in Offshore Moonpool Operations - Experimental Results

    Directory of Open Access Journals (Sweden)

    Tor A. Johansen

    2004-01-01

    Full Text Available A new strategy for active control in heavy-lift offshore crane operations is suggested, by introducing a new concept referred to as wave synchronization. Wave synchronization reduces the hydrodynamic forces by minimization of variations in the relative vertical velocity between payload and water using a wave amplitude measurement. Wave synchronization is combined with conventional active heave compensation to obtain accurate control. Experimental results using a scale model of a semi-submerged vessel with a moonpool shows that wave synchronization leads to significant improvements in performance. Depending on the sea state and payload, the results indicate that the reduction in the standard deviation of the wire tension may be up to 50

  18. Maternal hypothyroidism: An overview of current experimental models.

    Science.gov (United States)

    Ghanbari, Mahboubeh; Ghasemi, Asghar

    2017-10-15

    Maternal hypothyroidism (MH) is the most common cause of transient congenital hypothyroidism. Different animal models are used for assessing developmental effects of MH in offspring. The severity and status of hypothyroidism in animal models must be a reflection of the actual conditions in humans. To obtain comparable results with different clinical conditions, which lead to MH in humans, several factors have been suggested for researchers to consider before designing the experimental models. Regarding development of fetal body systems during pregnancy, interference at different times provides different results and the appropriate time for induction of hypothyroidism should be selected based on accurate time of development of the system under assessment. Other factors that should be taken into consideration include, physiological and biochemical differences between humans and other species, thyroid hormone-independent effects of anti-thyroid drugs, circadian rhythms in TSH secretion, sex differences, physical and psychological stress. This review addresses essential guidelines for selecting and managing the optimal animal model for MH as well as discussing the pros and cons of currently used models. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Experimental Validation of a Permeability Model for Enrichment Membranes

    International Nuclear Information System (INIS)

    Orellano, Pablo; Brasnarof, Daniel; Florido Pablo

    2003-01-01

    An experimental loop with a real scale diffuser, in a single enrichment-stage configuration, was operated with air at different process conditions, in order to characterize the membrane permeability.Using these experimental data, an analytical geometric-and-morphologic-based model was validated.It is conclude that a new set of independent measurements, i.e. enrichment, is necessary in order to fully characterize diffusers, because of its internal parameters are not univocally determinated with permeability experimental data only

  20. Experimental Modeling of the Formation of Saucer-Shaped sills

    Science.gov (United States)

    Galland, O.; Planke, S.; Malthe-Sorenssen, A.

    2007-12-01

    Many magma intrusions in sedimentary basins are sills, and especially saucer-shaped sills. These features are observed in many places (i.e. South Africa; the Norwegian and North Sea; Siberia; Argentina). Sand injectites exhibit similar geometries. The occurrence of such features in so various settings suggests that their emplacement results from fundamental processes in sedimentary basins. To understand such processes, we performed experimental modeling of saucer-shaped sill emplacement. The experiments consist of injecting a molten low viscosity vegetable oil (model magma) at a constant flow rate into a fine-grained Coulomb silica flour (model rock). When the oil starts intruding, the initially flat surface of the model inflates and forms a smooth dome. At the end of the experiment, the oil erupts at the edge of the dome. After the experiment, the oil cools and solidifies, the resulting solid intrusion is unburied and exposed, and its upper surface digitalized. For our purpose, we did our experiments without external deformation. We performed two series of experiments with varying depth of injection. The first series consisted of injection into a homogeneous medium. The resulting intrusions were cone-sheets and dykes. The second series consisted of heterogeneous models where the heterogeneity was a weak layer made of a flexible net. The resulting intrusions were made of (1) a horizontal basal sill emplaced along the weakness, and (2) inclined sheets nucleating at the edges of the basal sill and propagating upward and outward. The inclined sheets exhibited a convex shape, i.e. a decreasing slope outward. In addition, the deeper the sills emplaced, the larger they were. Our experimental results are consistent with saucer-shaped features in nature. We infer from our results that the transition between the basal sills and the inclined sheets results from a transition of emplacement processes. We suggest that the basal sill emplace by open (mode I) fracturing, whereas

  1. Results of a model for premixed combustion oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Janus, M.C.; Richards, G.A.

    1996-09-01

    Combustion oscillations are receiving renewed research interest due to increasing use of lean premix (LPM) combustion to gas turbines. A simple, nonlinear model for premixed combustion is described in this paper. The model was developed to help explain specific experimental observations and to provide guidance for development of active control schemes based on nonlinear concepts. The model can be used to quickly examine instability trends associated with changes in equivalence ratio, mass flow rate, geometry, ambient conditions, etc. The model represents the relevant processes occurring in a fuel nozzle and combustor which are analogous to current LPM turbine combustors. Conservation equations for the fuel nozzle and combustor are developed from simple control volume analysis, providing a set of ordinary differential equations that can be solved on a personal computer. Combustion is modeled as a stirred reactor, with a bimolecular reaction rate between fuel and air. A variety of numerical results and comparisons to experimental data are presented to demonstrate the utility of the model. Model results are used to understand the fundamental mechanisms which drive combustion oscillations, effects of inlet air temperature and nozzle geometry on instability, and effectiveness of open loop control schemes.

  2. A DIDATIC EXPERIENCE IN BIOCHEMISTRY LABWORKS: THEORETICALVERSUS EXPERIMENTAL MODEL

    Directory of Open Access Journals (Sweden)

    B.C Rossi-Rodrigues

    2008-05-01

    Full Text Available Biochemistry labworks are fundamental to both the instrumentation and  for  the  establishment of important concepts. The labworks of Basic  Biochemistry  (BB280 for Biology students at UNICAMP have gone through several  improvements. The labworks are  now  structured  from simple  activities to more complex ones, and aimed  to  the student’s  autonomy  development  in the experiments planning and execution  over  the teaching  semester. The first practical activity is on buffer systems, and   it is based  on  the confrontation of a theoretical model with the  lab experiments results.  First of all, the students  simulate  a Titration  in  a computational environment, where students lay a theoretical model from their knowledge. In the theoretical model the buffer parameters are set according to the teacher instructions, and the experiment conditions are also set and tested.  The simulation results are used for planning  the experiment and to compare with the experimental ones.  After having the simulations concluded and having the experiment planned the students  perform  the  in lab  Titration with the parameters established in the simulation. The results obtained by students are presented in a report. We analyzed the reports from 76 BB280’s students in 2007(night class and day class. The students identified as the main causes of the discrepancy between theoretical and experimental data: 1 experimental errors, related to the lack of technical skill 2 limitation of equipment used 3 unexpected behavior of the substances  used. In addition to the theoretical content related to  labwork, the confrontation between the  simulation and experimentation provided the students with ability  to identify the main aspects of which can influence the quality of the data obtained.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    estimates obtained from vibration experiments. Modal testing results are influenced by numerous factors introducing uncertainty to the measurement results. Different experimental techniques applied to the same test item or testing numerous nominally identical specimens yields different test results...

  4. Protection of estrogen in portal hypertension gastropathy: an experimental model

    Directory of Open Access Journals (Sweden)

    Maria Isabel Morgan-Martins

    2011-09-01

    Full Text Available CONTEXT: Portal hypertension is a complication secondary to cirrhosis that is characterized by increased blood flow and/or vascular resistance in the portal system, causing the appearance of a hyperdynamic collateral circulation. Partial portal vein ligation is an experimental model used in rats to study the pathophysiological mechanisms involved in pre-hepatic portal hypertension. Estrogen E2 is an antioxidant molecule with various physiological actions. OBJECTIVES: To evaluate the antioxidant activity of endogenous estrogen in an experimental model of partial portal vein ligation by comparing intact with castrated rats. METHODS: Twenty Wistar rats, weighing on average 250 g were used and divided into four groups: sham-operated (SO; intact (I with partial portal vein ligation (I + PPVL, castrated (C and castrated with partial ligation of the vein (C + PPVL. Day 1: castration or sham-operation; day 7, PPVL surgery; on day 15 post-PPVL, portal pressure in the mesenteric vein of rats was measured on polygraph Letica. Lipid peroxidation in the stomach was assessed using the technique of thiobarbituric acid reactive substances and activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase. Statistical analysis was done with ANOVA - Student-Newman-Keuls (mean ± SE, and P<0.05 was considered as significant. RESULTS: Portal pressure was significantly increased in C + PPVL as compared to the other groups. There was no significant difference in the group of intact rats. TBARS showed significant damage in C and C + PPVL in relation to others. Antioxidant enzymes were significantly increased in the castrated rats with subsequent PPVL as compared to the other groups. CONCLUSION: We suggest that estrogen E2 plays a protective role in intact compared with castrated rats because it presents hydrophenolic radicals in its molecule, thus acting as an antioxidant in this experimental model.

  5. Experimental modeling of a deoiling hydrocyclone system

    DEFF Research Database (Denmark)

    Bram, Mads Valentin; Hassan, Abdiladif Ahmed; Hansen, Dennis Severin

    2015-01-01

    Hydrocyclones used in offshore oil & gas industries utilizes pressure difference ratio (PDR) control to maintain efficient oil and water separation. This separation will reduce the concentration of oil in the effluent water to fulfill the environmental safety limits of low oil concentrations....... This limitation causes the optimization of the separation process to be an important research. As oscillating flow affects the hydrocyclones performance, it is important to identify the dynamic model of the hydrocyclones to possibly optimize and improve the current PDR control solution. An in-house developed...

  6. Experimental modeling methods in Industrial Engineering

    Directory of Open Access Journals (Sweden)

    Peter Trebuňa

    2009-03-01

    Full Text Available Dynamic approaches to a management system of the present industrial practice, forcing businesses to address management issues in-house continuous improvement of production and non-production processes. Experience has repeatedly demonstrated the need for a system approach not only in analysis but also in the planning and actual implementation of these processes. Therefore, the contribution is focused on the description of the modeling in industrial practice by a system approach, in order to avoid erroneous application of the decision to the implementation phase, and thus prevent any longer applying methods "attempt - fallacy".

  7. Experimental validation of models for Plasma Focus devices

    International Nuclear Information System (INIS)

    Rodriguez Palomino, Luis; Gonzalez, Jose; Clausse, Alejandro

    2003-01-01

    Plasma Focus(PF) Devices are thermonuclear pulsators that produce short pulsed radiation (X-ray, charged particles and neutrons). Since Filippov and Mather, investigations have been used to study plasma properties. Nowadays the interest about PF is focused in technology applications, related to the use of these devices as pulsed neutron sources. In the numerical calculus the Inter institutional PLADEMA (PLAsmas DEnsos MAgnetizados) network is developing three models. Each one is useful in different engineering stages of the Plasma Focus design. One of the main objectives in this work is a comparative study on the influence of the different parameters involved in each models. To validate these results, several experimental measurements under different geometry and initial conditions were performed. (author)

  8. Astrocyte regulation of sleep circuits: experimental and modeling perspectives

    Directory of Open Access Journals (Sweden)

    Tommaso eFellin

    2012-08-01

    Full Text Available Integrated within neural circuits, astrocytes have recently been shown to modulate brain rhythms thought to mediate sleep function. Experimental evidence suggests that local impact of astrocytes on single synapses translates into global modulation of neuronal networks and behavior. We discuss these findings in the context of current conceptual models of sleep generation and function, each of which have historically focused on neural mechanisms. We highlight the implications and the challenges introduced by these results from a conceptual and computational perspective. We further provide modeling directions on how these data might extend our knowledge of astrocytic properties and sleep function. Given our evolving understanding of how local cellular activities during sleep lead to functional outcomes for the brain, further mechanistic and theoretical understanding of astrocytic contribution to these dynamics will undoubtedly be of great basic and translational benefit.

  9. An experimental and modeling study of n-octanol combustion

    KAUST Repository

    Cai, Liming

    2015-01-01

    This study presents the first investigation on the combustion chemistry of n-octanol, a long chain alcohol. Ignition delay times were determined experimentally in a high-pressure shock tube, and stable species concentration profiles were obtained in a jet stirred reactor for a range of initial conditions. A detailed kinetic model was developed to describe the oxidation of n-octanol at both low and high temperatures, and the model shows good agreement with the present dataset. The fuel\\'s combustion characteristics are compared to those of n-alkanes and to short chain alcohols to illustrate the effects of the hydroxyl moiety and the carbon chain length on important combustion properties. Finally, the results are discussed in detail. © 2014 The Combustion Institute.

  10. CFD Modeling and Experimental Validation of a Solar Still

    Directory of Open Access Journals (Sweden)

    Mahmood Tahir

    2017-01-01

    Full Text Available Earth is the densest planet of the solar system with total area of 510.072 million square Km. Over 71.68% of this area is covered with water leaving a scant area of 28.32% for human to inhabit. The fresh water accounts for only 2.5% of the total volume and the rest is the brackish water. Presently, the world is facing chief problem of lack of potable water. This issue can be addressed by converting brackish water into potable through a solar distillation process and solar still is specially assigned for this purpose. Efficiency of a solar still explicitly depends on its design parameters, such as wall material, chamber depth, width and slope of the zcondensing surface. This study was aimed at investigating the solar still parameters using CFD modeling and experimental validation. The simulation data of ANSYS-FLUENT was compared with actual experimental data. A close agreement among the simulated and experimental results was seen in the presented work. It reveals that ANSYS-FLUENT is a potent tool to analyse the efficiency of the new designs of the solar distillation systems.

  11. Computational and experimental model of transdermal iontophorethic drug delivery system.

    Science.gov (United States)

    Filipovic, Nenad; Saveljic, Igor; Rac, Vladislav; Graells, Beatriz Olalde; Bijelic, Goran

    2017-11-30

    The concept of iontophoresis is often applied to increase the transdermal transport of drugs and other bioactive agents into the skin or other tissues. It is a non-invasive drug delivery method which involves electromigration and electroosmosis in addition to diffusion and is shown to be a viable alternative to conventional administration routs such as oral, hypodermic and intravenous injection. In this study we investigated, experimentally and numerically, in vitro drug delivery of dexamethasone sodium phosphate to porcine skin. Different current densities, delivery durations and drug loads were investigated experimentally and introduced as boundary conditions for numerical simulations. Nernst-Planck equation was used for calculation of active substance flux through equivalent model of homogeneous hydrogel and skin layers. The obtained numerical results were in good agreement with experimental observations. A comprehensive in-silico platform, which includes appropriate numerical tools for fitting, could contribute to iontophoretic drug-delivery devices design and correct dosage and drug clearance profiles as well as to perform much faster in-silico experiments to better determine parameters and performance criteria of iontophoretic drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Hybrid Electric Vehicle Experimental Model with CAN Network Real Time Control

    Directory of Open Access Journals (Sweden)

    RATOI, M.

    2010-05-01

    Full Text Available In this paper an experimental model with a distributed control system of a hybrid electrical vehicle is presented. A communication CAN network of high speed (1 Mbps assures a distributed control of the all components. The modeling and the control of different operating regimes are realized on an experimental test-bench of a hybrid electrical vehicle. The experimental results concerning the variations of the mains variables (currents, torques, speeds are presented.

  13. Recent experimental results in sub- and near-barrier heavy-ion fusion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Montagnoli, Giovanna [Dipartimento di Fisica e Astronomia, Universita di Padova (Italy); INFN Sezione di Padova (Italy); Stefanini, Alberto M. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy)

    2017-08-15

    Recent advances obtained in the field of near and sub-barrier heavy-ion fusion reactions are reviewed. Emphasis is given to the results obtained in the last decade, and focus is mainly on the experimental work performed concerning the influence of transfer channels on fusion cross sections and the hindrance phenomenon far below the barrier. Indeed, early data of sub-barrier fusion taught us that cross sections may strongly depend on the low-energy collective modes of the colliding nuclei, and, possibly, on couplings to transfer channels. The coupled-channels (CC) model has been quite successful in the interpretation of the experimental evidences. Fusion barrier distributions often yield the fingerprint of the relevant coupled channels. Recent results obtained by using radioactive beams are reported. At deep sub-barrier energies, the slope of the excitation function in a semi-logarithmic plot keeps increasing in many cases and standard CC calculations overpredict the cross sections. This was named a hindrance phenomenon, and its physical origin is still a matter of debate. Recent theoretical developments suggest that this effect, at least partially, may be a consequence of the Pauli exclusion principle. The hindrance may have far-reaching consequences in astrophysics where fusion of light systems determines stellar evolution during the carbon and oxygen burning stages, and yields important information for exotic reactions that take place in the inner crust of accreting neutron stars. (orig.)

  14. Comparison of dynamic analysis of a Schilling hydraulic manipulator with experimental results

    International Nuclear Information System (INIS)

    Baker, C.P.; Lew, J.Y.; Evans, M.S.; Magee, D.P.

    1993-07-01

    Two independent models of the dynamics of a Schilling Titan II hydraulic manipulator were developed and compared in order to obtain an accurate model of the manipulator dynamics. These models will be used in the development of feedback control laws and active damping algorithms. One of the model is an analytical model which was developed open-quotes by handclose quotes with the assistance of computer symbolic manipulation. The other is a numerical model developed using a commercially available dynamics code. The data from these models were then compared with experimental data from an actual Titan II manipulator

  15. Mathematical Models and the Experimental Analysis of Behavior

    Science.gov (United States)

    Mazur, James E.

    2006-01-01

    The use of mathematical models in the experimental analysis of behavior has increased over the years, and they offer several advantages. Mathematical models require theorists to be precise and unambiguous, often allowing comparisons of competing theories that sound similar when stated in words. Sometimes different mathematical models may make…

  16. Experimental Tests of the Algebraic Cluster Model

    Science.gov (United States)

    Gai, Moshe

    2018-02-01

    The Algebraic Cluster Model (ACM) of Bijker and Iachello that was proposed already in 2000 has been recently applied to 12C and 16O with much success. We review the current status in 12C with the outstanding observation of the ground state rotational band composed of the spin-parity states of: 0+, 2+, 3-, 4± and 5-. The observation of the 4± parity doublet is a characteristic of (tri-atomic) molecular configuration where the three alpha- particles are arranged in an equilateral triangular configuration of a symmetric spinning top. We discuss future measurement with electron scattering, 12C(e,e’) to test the predicted B(Eλ) of the ACM.

  17. Experimental force modeling for deformation machining stretching ...

    Indian Academy of Sciences (India)

    ARSHPREET SINGH

    magnitude of forces rises significantly. The average resul- tant force rises to 768 N for 1.0 mm incremental step size from 327 N for 0.25 mm step size, keeping other parameters constant. It can be seen that the average resultant force is directly proportional to the incremental step size and fits well with the linear trend (Eq. 5) ...

  18. 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.

  19. Experimental tests of the standard model

    International Nuclear Information System (INIS)

    Nodulman, L.

    1998-01-01

    The title implies an impossibly broad field, as the Standard Model includes the fermion matter states, as well as the forces and fields of SU(3) x SU(2) x U(1). For practical purposes, I will confine myself to electroweak unification, as discussed in the lectures of M. Herrero. Quarks and mixing were discussed in the lectures of R. Aleksan, and leptons and mixing were discussed in the lectures of K. Nakamura. I will essentially assume universality, that is flavor independence, rather than discussing tests of it. I will not pursue tests of QED beyond noting the consistency and precision of measurements of α EM in various processes including the Lamb shift, the anomalous magnetic moment (g-2) of the electron, and the quantum Hall effect. The fantastic precision and agreement of these predictions and measurements is something that convinces people that there may be something to this science enterprise. Also impressive is the success of the ''Universal Fermi Interaction'' description of beta decay processes, or in more modern parlance, weak charged current interactions. With one coupling constant G F , most precisely determined in muon decay, a huge number of nuclear instabilities are described. The slightly slow rate for neutron beta decay was one of the initial pieces of evidence for Cabbibo mixing, now generalized so that all charged current decays of any flavor are covered

  20. Experimental tests of the standard model.

    Energy Technology Data Exchange (ETDEWEB)

    Nodulman, L.

    1998-11-11

    The title implies an impossibly broad field, as the Standard Model includes the fermion matter states, as well as the forces and fields of SU(3) x SU(2) x U(1). For practical purposes, I will confine myself to electroweak unification, as discussed in the lectures of M. Herrero. Quarks and mixing were discussed in the lectures of R. Aleksan, and leptons and mixing were discussed in the lectures of K. Nakamura. I will essentially assume universality, that is flavor independence, rather than discussing tests of it. I will not pursue tests of QED beyond noting the consistency and precision of measurements of {alpha}{sub EM} in various processes including the Lamb shift, the anomalous magnetic moment (g-2) of the electron, and the quantum Hall effect. The fantastic precision and agreement of these predictions and measurements is something that convinces people that there may be something to this science enterprise. Also impressive is the success of the ''Universal Fermi Interaction'' description of beta decay processes, or in more modern parlance, weak charged current interactions. With one coupling constant G{sub F}, most precisely determined in muon decay, a huge number of nuclear instabilities are described. The slightly slow rate for neutron beta decay was one of the initial pieces of evidence for Cabbibo mixing, now generalized so that all charged current decays of any flavor are covered.

  1. Experimental Validation of Flow Force Models for Fast Switching Valves

    DEFF Research Database (Denmark)

    Bender, Niels Christian; Pedersen, Henrik Clemmensen; Nørgård, Christian

    2017-01-01

    This paper comprises a detailed study of the forces acting on a Fast Switching Valve (FSV) plunger. The objective is to investigate to what extend different models are valid to be used for design purposes. These models depend on the geometry of the moving plunger and the properties of the surroun......This paper comprises a detailed study of the forces acting on a Fast Switching Valve (FSV) plunger. The objective is to investigate to what extend different models are valid to be used for design purposes. These models depend on the geometry of the moving plunger and the properties...... velocity is non-zero. This is the case in FSVs, where it results in an additional dampening effect, which is of relevance when analyzing contact-impact. Experimental data from different tests cases of a FSV has been gathered, with the plunger moving through a medium of either oil or air. This data is used...... to compare and validate different models, where an effort is directed towards capturing the fluid squeeze effect just before material on material contact. The test data is compared with simulation data relying solely on analytic formulations. The general dynamics of the plunger is validated...

  2. Experimental Septic Shock: Models and Mechanisms

    Science.gov (United States)

    1976-06-14

    I. Woolf, P. J. O’Regan, C. Beach, C. Hasinoff, and W. H. Sutherland. Impaired gluconeogenesis in dogs with E. coli bacteremia. Surgery 76:533, 1974...rats administered endotoxin (9,18), dogs given endotoxin (1,2,14) or live E. coli organisms (10,11,13), and nonhuman primates receiving endotoxin...8217 ’ • ,, - , -• --" :" ,• ... ., ., -. .- " - . ..... . . . I3 in dogs is 2.5 mg/kg, while even a dose of 40 mg/kg in one baboon did not result in its death during a 24-hour period. A separate

  3. Impact of model defect and experimental uncertainties on evaluated output

    International Nuclear Information System (INIS)

    Neudecker, D.; Capote, R.; Leeb, H.

    2013-01-01

    One of the current major problems in nuclear data evaluation is the unreasonably small evaluated uncertainties often obtained. These small uncertainties are partly attributed to missing correlations of experimental uncertainties as well as to deficiencies of the model employed for the prior information. In this article, both uncertainty sources are included in an evaluation of 55 Mn cross-sections for incident neutrons. Their impact on the evaluated output is studied using a prior obtained by the Full Bayesian Evaluation Technique and a prior obtained by the nuclear model program EMPIRE. It is shown analytically and by means of an evaluation that unreasonably small evaluated uncertainties can be obtained not only if correlated systematic uncertainties of the experiment are neglected but also if prior uncertainties are smaller or about the same magnitude as the experimental ones. Furthermore, it is shown that including model defect uncertainties in the evaluation of 55 Mn leads to larger evaluated uncertainties for channels where the model is deficient. It is concluded that including correlated experimental uncertainties is equally important as model defect uncertainties, if the model calculations deviate significantly from the measurements. -- Highlights: • We study possible causes of unreasonably small evaluated nuclear data uncertainties. • Two different formulations of model defect uncertainties are presented and compared. • Smaller prior than experimental uncertainties cause too small evaluated ones. • Neglected correlations of experimental uncertainties cause too small evaluated ones. • Including model defect uncertainties in the prior improves the evaluated output

  4. Experimental Investigation and Theoretical Modeling of Nanosilica Activity in Concrete

    Directory of Open Access Journals (Sweden)

    Han-Seung Lee

    2014-01-01

    Full Text Available This paper presents experimental investigations and theoretical modeling of the hydration reaction of nanosilica blended concrete with different water-to-binder ratios and different nanosilica replacement ratios. The developments of chemically bound water contents, calcium hydroxide contents, and compressive strength of Portland cement control specimens and nanosilica blended specimens were measured at different ages: 1 day, 3 days, 7 days, 14 days, and 28 days. Due to the pozzolanic reaction of nanosilica, the contents of calcium hydroxide in nanosilica blended pastes are considerably lower than those in the control specimens. Compared with the control specimens, the extent of compressive strength enhancement in the nanosilica blended specimens is much higher at early ages. Additionally, a blended cement hydration model that considers both the hydration reaction of cement and the pozzolanic reaction of nanosilica is proposed. The properties of nanosilica blended concrete during hardening were evaluated using the degree of hydration of cement and the reaction degree of nanosilica. The calculated chemically bound water contents, calcium hydroxide contents, and compressive strength were generally consistent with the experimental results.

  5. Carbide Type Influence on Tribological Properties of Hard Faced Steel Layer Part II- Experimental Results

    Directory of Open Access Journals (Sweden)

    V. Lazic

    2010-09-01

    Full Text Available In this paper is presented a preceding procedure that should be conducted in order to successfully regenerate damaged forging dies by the hard facing process. After the tool damage types identification, as well as their causes, we have chosen the procedure and the parameters of hard facing that we further corrected by conducting the test hard facings on models. Thus, we were able to relate the experimental results outputs with the repair technology, taking as a criterion the quality of the surface layers wear resistance such as friction coefficient and width of hard faced zone, hardness and its distribution in cross section, then microstructure of characteristic of hard faced zones, etc. This research points out significancy of tribological properties of certain types of carbides and their effects on metal matrix, in which carbides are embedded. Our tribological investigations have shown that the working life of the hard faced tool can be longer than that of the new tool.

  6. Benchmark of Space Charge Simulations and Comparison with Experimental Results for High Intensity, Low Energy Accelerators

    CERN Document Server

    Cousineau, Sarah M

    2005-01-01

    Space charge effects are a major contributor to beam halo and emittance growth leading to beam loss in high intensity, low energy accelerators. As future accelerators strive towards unprecedented levels of beam intensity and beam loss control, a more comprehensive understanding of space charge effects is required. A wealth of simulation tools have been developed for modeling beams in linacs and rings, and with the growing availability of high-speed computing systems, computationally expensive problems that were inconceivable a decade ago are now being handled with relative ease. This has opened the field for realistic simulations of space charge effects, including detailed benchmarks with experimental data. A great deal of effort is being focused in this direction, and several recent benchmark studies have produced remarkably successful results. This paper reviews the achievements in space charge benchmarking in the last few years, and discusses the challenges that remain.

  7. Experimental and numerical investigation of a simplified exhaust model

    Directory of Open Access Journals (Sweden)

    Balázs Vehovszky

    2016-10-01

    Full Text Available A simplified experimental equipment was built to investigate heat radiation and free convection around hot exhaust pipe. Temperatures were measured on the surface of the pipe as like as on heat insulating and -reflecting aluminum shield. Special care was taken to the temperature measuring method: result proved that inappropriate fixing of measuring thermocouples lead to an error of up to 30 % in the temperature-increase values. A detailed 1D numerical model was set up and parametrized so as to the calculation results can be fitted to measured temperature values. In this way thermal properties of the surfaces – as emissivities, absorption coefficients and convective heat transfer coefficients – were determined for temperature sweeps and stationary state cases. The used methods are to be further improved for real automotive parts and higher temperatures.

  8. Experimental characterisation of sprays resulting from impacts of liquid-containing projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Hostikka, Simo, E-mail: simo.hostikka@aalto.fi [Aalto University, Espoo (Finland); Silde, Ari; Sikanen, Topi; Vepsä, Ari; Paajanen, Antti [VTT Technical Research Centre of Finland Ltd, Espoo (Finland); Honkanen, Markus [Pixact Oy, Tampere (Finland)

    2015-12-15

    Highlights: • Detailed characterisation of sprays resulting from the impacts of water-filled metal projectiles on a hard wall. • Experimental measurements of spray speed, direction and droplet size. • Detailed analysis of overall spray evolution. • The spray characterisation information can be used in CFD analyses of aircraft impact fires. - Abstract: Modelling and analysing fires following aircraft impacts requires information about the behaviour of liquid fuel. In this study, we investigated sprays resulting from the impacts of water-filled metal projectiles on a hard wall. The weights of the projectiles were in the range of 38–110 kg, with 8.6–68 kg water, and the impact speeds varied between 96 and 169 m/s. The overall spray behaviour was observed with high-speed video cameras. Ultra-high-speed cameras were used in backlight configuration for measuring the droplet size and velocity distributions. The results indicate that the liquid leaves the impact position as a thin sheet of spray in a direction perpendicular to the projectile velocity. The initial spray speeds were 1.5–2.5 times the impact speed, and the Sauter mean diameters were in the 147–344 μm range. This data can be used as boundary conditions in CFD fire analyses, considering the two-phase fuel flow. The overall spray observations, including the spray deceleration rate, can be used for validating the model.

  9. Powered Paraglider Longitudinal Dynamic Modeling and Experimentation

    Science.gov (United States)

    Gibson, Colin P.

    Paragliders and similar controllable decelerators provide the benefits of a compact packable parachute with the improved glide performance and steering of a conventional wing, making them ideally suited for precise high offset payload recovery and airdrop missions. This advantage over uncontrollable conventional parachutes sparked interest from Oklahoma State University for implementation into its Atmospheric and Space Threshold Research Oklahoma (ASTRO) program, where payloads often descend into wooded areas. However, due to complications while building a powered paraglider to evaluate the concept, more research into its design parameters was deemed necessary. Focus shifted to an investigation of the effects of these parameters on the flight behavior of a powered system. A longitudinal dynamic model, based on Lagrange's equation for adaptability when adding free-hanging masses, was developed to evaluate trim conditions and analyze system response. With the simulation, the effects of rigging angle, fuselage weight, center of gravity (cg), and apparent mass were calculated through step thrust input cases. Test flights evaluated the behavior of the paraglider, and the design was revised based on observations and analysis. Rigging angle sets the power-off glide slope as well as thrust capacity and input response damping. At more negative angles the glide slope is steeper, can handle more thrust, and damps quicker at a lower frequency. The fuselage weight, or loading, affects thrust capacity and power-off sink rate, with heavier gliders capable of larger thrust inputs but faster descent speed; however, the glide slope remains unchanged. As the cg position is place forward of the attachment point the incidence angle and thrust line will rotate downward, while the opposite occurs moving aft. For the test vehicle, a slightly forward position allowed for the greatest thrust input, and far forward reduced performance for equivalent thrust compared to far aft. Three test

  10. Anti-granuloma activity of Coriandrum sativum in experimental models

    Science.gov (United States)

    Nair, Vinod; Singh, Surender; Gupta, Yogendra Kumar

    2013-01-01

    Background: Coriandrum sativum has been used in the traditional systems of medicine for management of arthritis and other inflammatory disorders. Objectives: In this study, we have evaluated the anti-inflammatory and anti-granuloma activities of Coriandrum sativum hydroalcoholic extract (CSHE) in experimental models. Materials and Methods: The anti-inflammatory activity of CSHE was evaluated using carrageenan-induced paw edema model and the anti-granuloma activity of CSHE was evaluated using the subcutaneous cotton pellet implantation-induced granuloma formation and stimulation of peritoneal macrophages with complete Freund's adjuvant. Serum tumor necrosis factor-α (TNF-α), IL-6, IL-1 β levels, and peritoneal macrophage expression of TNF-R1 were evaluated as markers of global inflammation. Results: CSHE at the highest dose tested (32 mg/kg) produced a significant reduction (P < 0.05) in paw edema after carrageenan administration. CSHE treatment also reduced dry granuloma weight in all treated animals. Serum IL-6 and IL-1 β levels were significantly (P < 0.05) lower in the CSHE (32 mg/kg)-treated group as compared to control. Although there was an increase in serum TNF-α level in the CSHE-treated group as compared to control, TNF-R1 expression on peritoneal macrophages was found to be reduced. Conclusion: Thus, the result of this study demonstrates the anti-inflammatory and anti-granuloma activities of CSHE in experimental models, and validates its traditional use for the management of arthritis and other inflammatory disorders. PMID:23741156

  11. Experimental Estimation Of Energy Damping During Free Rocking Of Unreinforced Masonry Walls. First Results

    International Nuclear Information System (INIS)

    Sorrentino, Luigi; Masiani, Renato; Benedetti, Stefano

    2008-01-01

    This paper presents an ongoing experimental program on unreinforced masonry walls undergoing free rocking. Aim of the laboratory campaign is the estimation of kinetic energy damping exhibited by walls released with non-zero initial conditions of motion. Such energy damping is necessary for dynamic modelling of unreinforced masonry local mechanisms. After a brief review of the literature on this topic, the main features of the laboratory tests are presented. The program involves the experimental investigation of several parameters: 1) unit material (brick or tuff), 2) wall aspect ratio (ranging between 14.5 and 7.1), 3) restraint condition (two-sided or one-sided rocking), and 4) depth of the contact surface between facade and transverse walls (one-sided rocking only). All walls are single wythe and the mortar is pozzuolanic. The campaign is still in progress. However, it is possible to present the results on most of the mechanical properties of mortar and bricks. Moreover, a few time histories are reported, already indicating the need to correct some of the assumptions frequent in the literature

  12. Experimental results to determine the separation performance of the packages used in cryogenic distillation isotopes

    International Nuclear Information System (INIS)

    Bornea, A.M.; Stefanescu, I.; Zamfirache, M.; Balteanu, O.; Preda, A.

    2007-01-01

    The cryogenic distillation of the hydrogen isotopes represents the back-end separation process most efficient and usually used in detritiation technologies. In our institute there were made many researches in the field of hydrogen isotopes separation. The first results were obtained based on an experimental installation - Pilot Plant for heavy water production - and in present days using a Detritiation Pilot Plant. In our Institute, was manufactured and patented a lot of hydrophilic package for isotopic distillation of water and hydrogen and also catalysts used for isotopic exchange waterhydrogen. This items was continuously developed in order to increase the isotopic separation efficiency. The goal of this paper is to determine by experimental work the performance of the package manufactured in our institute used in the cryogenic distillation process. To describe the separation performances was developed a mathematical model for the cryogenic distillation of the hydrogen isotopes. In order to determine the characteristics of the package, the installation was operated in the total reflux mode, for different flow rate for the liquid. There were made several experiments considering different operating conditions corresponding to various values for the refrigeration power in the column condenser. From the bottom and the top of the distillation column there were extracted samples in order to determine the isotopic composition. Processing the experimental data obtained from these tests using the Fenske relation, we obtained the separation efficiency function of the power inside the column boiler, operating pressure and also pressure drop along the package. This efficiency is describe by the number of theoretical plates per meter (NTT/m) or by equivalent height of one theoretical plate (IETT). (orig.)

  13. The use of Alloxan and Streptozotocin in Experimental Diabetes Models

    Directory of Open Access Journals (Sweden)

    Zehra Kurçer

    2012-06-01

    Full Text Available Diabetes is a chronic metabolic disease which leads to several acute and chronic complications, morbidity and mortality, and decreased lifespan and quality of life. Therefore, in research studies that aim to enlighten the pathogenesis of diabetes and investigate possible treatment strategies, experimental animal models of diabetes provide many advantages to the investigator. Models of diabetes obtained by chemical induction, diet, surgical manipulations or combination thereof and also new genetically modified animal models are some of the experimental models. Alloxan and streptozotocin (STZ, which are toxic glucose analogues that preferentially accumulate in pancreatic beta cells, are widely used toxic agents to induce experimental diabetes in animals. This review gives an overview on the use of alloxan and STZ to induce chemical diabetes models with reference to their mechanisms, utilizable doses, advantages and disadvantages in diabetes research. Turk Jem 2012; 16: 34-40

  14. Integral Reactor Containment Condensation Model and Experimental Validation

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qiao [Oregon State Univ., Corvallis, OR (United States); Corradini, Michael [Univ. of Wisconsin, Madison, WI (United States)

    2016-05-02

    This NEUP funded project, NEUP 12-3630, is for experimental, numerical and analytical studies on high-pressure steam condensation phenomena in a steel containment vessel connected to a water cooling tank, carried out at Oregon State University (OrSU) and the University of Wisconsin at Madison (UW-Madison). In the three years of investigation duration, following the original proposal, the planned tasks have been completed: (1) Performed a scaling study for the full pressure test facility applicable to the reference design for the condensation heat transfer process during design basis accidents (DBAs), modified the existing test facility to route the steady-state secondary steam flow into the high pressure containment for controllable condensation tests, and extended the operations at negative gage pressure conditions (OrSU). (2) Conducted a series of DBA and quasi-steady experiments using the full pressure test facility to provide a reliable high pressure condensation database (OrSU). (3) Analyzed experimental data and evaluated condensation model for the experimental conditions, and predicted the prototypic containment performance under accidental conditions (UW-Madison). A film flow model was developed for the scaling analysis, and the results suggest that the 1/3 scaled test facility covers large portion of laminar film flow, leading to a lower average heat transfer coefficient comparing to the prototypic value. Although it is conservative in reactor safety analysis, the significant reduction of heat transfer coefficient (50%) could under estimate the prototypic condensation heat transfer rate, resulting in inaccurate prediction of the decay heat removal capability. Further investigation is thus needed to quantify the scaling distortion for safety analysis code validation. Experimental investigations were performed in the existing MASLWR test facility at OrST with minor modifications. A total of 13 containment condensation tests were conducted for pressure

  15. Metabolic alterations in experimental models of depression

    Directory of Open Access Journals (Sweden)

    Maria G. Puiu

    2016-10-01

    Full Text Available Introduction: Major depressive disorder is one of the most prevalent psychiatric disorders and is associated with a severe impact on the personal functioning, thus with incurring significant direct and indirect costs. The presence of depression in patients with medical comorbidities increases the risks of myocardial infarction and decreases diabetes control, and adherence to treatment. The mechanism through which these effects are produced is still uncertain. Objectives of this study were to evaluate the metabolic alterations in female Wistar rats with induced depression, with and without administration of Agomelatine. The methods included two experiments. All data were analyzed by comparison with group I (control, and with each other. In the first experiment we induced depression by: exposure to chronic mild stress-group II; olfactory bulbectomy-group III; and exposure to chronic mild stress and hyperlipidic/ hyper caloric dietgroup IV. The second experiment was similar with the first but the rats received Agomelatine (0.16mg/ animal: group V (depression induced through exposure to chronic mild stress, VI (depression induced through olfactory bulbectomy and VII (depression induced through exposure to chronic mild stressing hyperlipidic/ hypercaloric diet. Weight, cholesterol, triglycerides and glycaemia were measured at day 0 and 28, and leptin value was measured at day 28. The results in the 1st experiment revealed significant differences (p<0.01 for weight and cholesterol in Group IV, for triglycerides in groups III and IV (p<0.001, and for glycaemia in group II. The 2nd experiment revealed significant differences (p<0.001 in group VII for weight and triglycerides, and in groups V and VI for triglycerides (p<0.01. In conclusion, significant correlations were found between high level of triglycerides and depression induced by chronic stress and olfactory bulbectomy. Agomelatine groups had a lower increase of triglycerides levels.

  16. Seismoelectric interface response : Experimental results and forward model

    NARCIS (Netherlands)

    Schakel, M.D.; Smeulders, D.M.J.; Slob, E.C.; Heller, H.K.J.

    2011-01-01

    Understanding the seismoelectric interface response is important for developing seismoelectric field methods for oil exploration and environmental/engineering geophysics. The existing seismoelectric theory has never been validated systematically by controlled experiments. We have designed and

  17. SSI on the Dynamic Behaviour of a Historical Masonry Building: Experimental versus Numerical Results

    Directory of Open Access Journals (Sweden)

    Francesca Ceroni

    2014-11-01

    Full Text Available A reliable procedure to identify the dynamic behaviour of existing masonry buildings is described in the paper, referring to a representative case study: a historical masonry palace located in Benevento (Italy. Since the building has been equipped with a permanent dynamic monitoring system by the Department of Civil Protection, some of the recorded data, acquired in various operating conditions, have been analysed with basic instruments of the Operational Modal Analysis in order to identify the main eigenfrequencies and vibration modes of the structure. The obtained experimental results have been compared to the numerical outcomes provided by three detailed Finite Element (FE models of the building. The influence of Soil-Structure Interaction (SSI has been also introduced in the FE model by a sub-structure approach where concentrated springs were placed at the base of the building to simulate the effect of soil and foundation on the global dynamic behaviour of the structure. The obtained results evidence that subsoil cannot a priori be disregarded in identifying the dynamic response of the building.

  18. The Danish national passenger modelModel specification and results

    DEFF Research Database (Denmark)

    Rich, Jeppe; Hansen, Christian Overgaard

    2016-01-01

    , the paper provides a description of a large-scale forecast model with a discussion of the linkage between population synthesis, demand and assignment. Secondly, the paper gives specific attention to model specification and in particular choice of functional form and cost-damping. Specifically we suggest...... a family of logarithmic spline functions and illustrate how it is applied in the model. Thirdly and finally, we evaluate model sensitivity and performance by evaluating the distance distribution and elasticities. In the paper we present results where the spline-function is compared with more traditional...... function types and it is indicated that the spline-function provides a better description of the data. Results are also provided in the form of a back-casting exercise where the model is tested in a back-casting scenario to 2002....

  19. Experimental and modeling studies of mass transfer in ...

    African Journals Online (AJOL)

    Gaining a better understanding of mass transfer problems in encapsulated cell systems and in tissue engineering requires both experimental investigations and mathematical modelling. Specific mass transfer studies are reviewed including oxygen transfer in immobilised animal cell culture systems, modelling of ...

  20. Modeling methods for merging computational and experimental aerodynamic pressure data

    Science.gov (United States)

    Haderlie, Jacob C.

    This research describes a process to model surface pressure data sets as a function of wing geometry from computational and wind tunnel sources and then merge them into a single predicted value. The described merging process will enable engineers to integrate these data sets with the goal of utilizing the advantages of each data source while overcoming the limitations of both; this provides a single, combined data set to support analysis and design. The main challenge with this process is accurately representing each data source everywhere on the wing. Additionally, this effort demonstrates methods to model wind tunnel pressure data as a function of angle of attack as an initial step towards a merging process that uses both location on the wing and flow conditions (e.g., angle of attack, flow velocity or Reynold's number) as independent variables. This surrogate model of pressure as a function of angle of attack can be useful for engineers that need to predict the location of zero-order discontinuities, e.g., flow separation or normal shocks. Because, to the author's best knowledge, there is no published, well-established merging method for aerodynamic pressure data (here, the coefficient of pressure Cp), this work identifies promising modeling and merging methods, and then makes a critical comparison of these methods. Surrogate models represent the pressure data for both data sets. Cubic B-spline surrogate models represent the computational simulation results. Machine learning and multi-fidelity surrogate models represent the experimental data. This research compares three surrogates for the experimental data (sequential--a.k.a. online--Gaussian processes, batch Gaussian processes, and multi-fidelity additive corrector) on the merits of accuracy and computational cost. The Gaussian process (GP) methods employ cubic B-spline CFD surrogates as a model basis function to build a surrogate model of the WT data, and this usage of the CFD surrogate in building the WT

  1. Using an experimental model for the study of therapeutic touch.

    Science.gov (United States)

    dos Santos, Daniella Soares; Marta, Ilda Estéfani Ribeiro; Cárnio, Evelin Capellari; de Quadros, Andreza Urba; Cunha, Thiago Mattar; de Carvalho, Emilia Campos

    2013-02-01

    to verify whether the Paw Edema Model can be used in investigations about the effects of Therapeutic Touch on inflammation by measuring the variables pain, edema and neutrophil migration. this is a pilot and experimental study, involving ten male mice of the same genetic strain and divided into experimental and control group, submitted to the chemical induction of local inflammation in the right back paw. The experimental group received a daily administration of Therapeutic Touch for 15 minutes during three days. the data showed statistically significant differences in the nociceptive threshold and in the paw circumference of the animals from the experimental group on the second day of the experiment. the experiment model involving animals can contribute to study the effects of Therapeutic Touch on inflammation, and adjustments are suggested in the treatment duration, number of sessions and experiment duration.

  2. Modelling and Experimental Investigation of an Active Damper

    Directory of Open Access Journals (Sweden)

    Rafael Luís Teixeira

    2006-01-01

    Full Text Available This paper presents a validation methodology of the dynamic behavior of an active viscous damper. The damper has two flexible metallic bellows connected to a rigid reservoir filled with fluid. When one of the bellows is connected to a vibrating structure a periodic flow passes through a variable internal orifice and the damping effect is produced. The size of the orifice is adjusted by a controlled linear piezoelectric actuator that positions the conical core into a conical cavity. The device finite element structural model consists of the valve body and its conical core that are assumed rigid and the flexible bellows are represented by two pistons with elastic suspensions. The flow developed inside the damper is modeled considering the fluid-structure interation, using the Lagrangean-Eulerian formulation. To validate the proposed model a prototype was constructed and experimental tests and numerical simulations are accomplished in the time domain, applying harmonic excitations. The results are compared using curves that relate the damping coefficient with the orifice size and with the input velocity applied at the bellows face. However, for the proper control design and system operation, the direct use of the finite element model becomes unviable due to its high computational time. Then, a reduced second order discrete dynamic model for the damper was developed. The model parameters are identified by analysis in the frequency domain, using impulsive excitation force, for constant and variable orifice sizes. At low excitation frequencies, the damper prototype behaves like a single degree of freedom system which damping factor changes with the orifice size A fuzzy controller was designed and it generates the orifice reference size associated to the desired damping factor. The active system presented better performance when compared to the passive one.

  3. Scale Model Thruster Acoustic Measurement Results

    Science.gov (United States)

    Vargas, Magda; Kenny, R. Jeremy

    2013-01-01

    The Space Launch System (SLS) Scale Model Acoustic Test (SMAT) is a 5% scale representation of the SLS vehicle, mobile launcher, tower, and launch pad trench. The SLS launch propulsion system will be comprised of the Rocket Assisted Take-Off (RATO) motors representing the solid boosters and 4 Gas Hydrogen (GH2) thrusters representing the core engines. The GH2 thrusters were tested in a horizontal configuration in order to characterize their performance. In Phase 1, a single thruster was fired to determine the engine performance parameters necessary for scaling a single engine. A cluster configuration, consisting of the 4 thrusters, was tested in Phase 2 to integrate the system and determine their combined performance. Acoustic and overpressure data was collected during both test phases in order to characterize the system's acoustic performance. The results from the single thruster and 4- thuster system are discussed and compared.

  4. CMS standard model Higgs boson results

    Directory of Open Access Journals (Sweden)

    Garcia-Abia Pablo

    2013-11-01

    Full Text Available In July 2012 CMS announced the discovery of a new boson with properties resembling those of the long-sought Higgs boson. The analysis of the proton-proton collision data recorded by the CMS detector at the LHC, corresponding to integrated luminosities of 5.1 fb−1 at √s = 7 TeV and 19.6 fb−1 at √s = 8 TeV, confirm the Higgs-like nature of the new boson, with a signal strength associated with vector bosons and fermions consistent with the expectations for a standard model (SM Higgs boson, and spin-parity clearly favouring the scalar nature of the new boson. In this note I review the updated results of the CMS experiment.

  5. Prediction for disruption erosion of ITER plasma facing components; a comparison of experimental and numerical results

    International Nuclear Information System (INIS)

    Laan, J.G. van der; Akiba, M.; Seki, M.; Hassanein, A.; Tanchuk, V.

    1991-01-01

    An evaluation is given for the prediction for disruption erosion in the International Thermonuclear Engineering Reactor (ITER). At first, a description is given of the relation between plasma operating paramters and system dimensions to the predictions of loading parameters of Plasma Facing Components (PFC) in off-normal events. Numerical results from ITER parties on the prediction of disruption erosion are compared for a few typical cases and discussed. Apart from some differences in the codes, the observed discrepancies can be ascribed to different input data of material properties and boundary conditions. Some physical models for vapour shielding and their effects on numerical results are mentioned. Experimental results from ITER parties, obtained with electron and laser beams, are also compared. Erosion rates for the candidate ITER PFC materials are shown to depend very strongly on the energy deposition parameters, which are based on plasma physics considerations, and on the assumed material loss mechanisms. Lifetimes estimates for divertor plate and first wall armour are given for carbon, tungsten and beryllium, based on the erosion in the thermal quench phase. (orig.)

  6. Colloid filtration in surface dense vegetation: experimental results and theoretical predictions.

    Science.gov (United States)

    Wu, Lei; Muñoz-Carpena, Rafael; Gao, Bin; Yang, Wen; Pachepsky, Yakov A

    2014-04-01

    Understanding colloid and colloid-facilitated contaminant transport in overland flow through dense vegetation is important to protect water quality in the environment, especially for water bodies receiving agricultural and urban runoff. In previous studies, a single-stem efficiency theory for rigid and clean stem systems was developed to predict colloid filtration by plant stems of vegetation in laminar overland flow. Hence, in order to improve the accuracy of the single-stem efficiency theory to real dense vegetation system, we incorporated the effect of natural organic matter (NOM) on the filtration of colloids by stems. Laboratory dense vegetation flow chamber experiments and model simulations were used to determine the kinetic deposition (filtration) rate of colloids under various conditions. The results show that, in addition to flow hydrodynamics and solution chemistry, steric repulsion afforded by NOM layer on the plants stem surface also plays a significant role in controlling colloid deposition on vegetation in overland flow. For the first time, a refined single-stem efficiency theory with considerations of the NOM effect is developed that describes the experimental data with good accuracy. This theory can be used to not only help construct and refine mathematical models of colloid transport in real vegetation systems in overland flow, but also inform the development of theories of colloid deposition on NOM-coated surfaces in natural, engineered, and biomedical systems.

  7. Models of Investor Forecasting Behavior — Experimental Evidence

    Directory of Open Access Journals (Sweden)

    Federico Bonetto

    2017-12-01

    Full Text Available Different forecasting behaviors affect investors’ trading decisions and lead to qualitatively different asset price trajectories. It has been shown in the literature that the weights that investors place on observed asset price changes when forecasting future price changes, and the nature of their confidence when price changes are forecast, determine whether price bubbles, price crashes, and unpredictable price cycles occur. In this paper, we report the results of behavioral experiments involving multiple investors who participated in a market for a virtual asset. Our goal is to study investors’ forecast formation. We conducted three experimental sessions with different participants in each session. We fit different models of forecast formation to the observed data. There is strong evidence that the investors forecast future prices by extrapolating past price changes, even when they know the fundamental value of the asset exactly and the extrapolated forecasts differ significantly from the fundamental value. The rational expectations hypothesis seems inconsistent with the observed forecasts. The forecasting models of all participants that best fit the observed forecasting data were of the type that cause price bubbles and cycles in dynamical systems models, and price bubbles and cycles ended up occurring in all three sessions.

  8. Optimal experimental designs for inverse quadratic regression models

    OpenAIRE

    Dette, Holger; Kiss, Christine

    2007-01-01

    In this paper optimal experimental designs for inverse quadratic regression models are determined. We consider two different parameterizations of the model and investigate local optimal designs with respect to the $c$-, $D$- and $E$-criteria, which reflect various aspects of the precision of the maximum likelihood estimator for the parameters in inverse quadratic regression models. In particular it is demonstrated that for a sufficiently large design space geometric allocation rules are optim...

  9. U-drawing of Fortiform 1050 third generation steels. Numerical and experimental results

    Science.gov (United States)

    Saenz de Argandoña, E.; Galdos, L.; Mendiguren, J.; Otero, I.; Mugarra, E.

    2017-09-01

    Elasto-plastic behavior of the third generation Fortiform 1050 steel has been analysed using cyclic tension-compression tests. At the same time, the pseudo elastic modulus evolution with plastic strain was analysed using cyclic loading and unloading tests. From the experiments, it was found that the cyclic behavior of the steel is strongly kinematic and elastic modulus decrease with plastic strain is relevant for numerical modelling. In order to numerically analyse a U-Drawing process, strip drawing tests have been carried out at different contact pressures and Filzek model has been used to fit the experimental data and implement a pressure dependent friction law in Autoform software. Finally, numerical predictions of springback have been compared with the experimentally ones obtained using a sensorized U-Drawing tooling. Different material and contact models have been examined and most influencing parameters have been identified to model the forming of these new steels.

  10. 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

    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...... and was characterized by a decreasing trend with respect to the mean evaporator quality.The frictional pressure drop showed a linear dependence on the mean quality value and increased as the saturation temperature decreased. The experimental heat transfer coefficients were compared with a well-known correlation...

  11. Analysis and presentation of experimental results with examples, problems and programs

    CERN Document Server

    Christodoulides, Costas

    2017-01-01

    This book is intended as a guide to the analysis and presentation of experimental results. It develops various techniques for the numerical processing of experimental data, using basic statistical methods and the theory of errors. After presenting basic theoretical concepts, the book describes the methods by which the results can be presented, both numerically and graphically. The book is divided into three parts, of roughly equal length, addressing the theory, the analysis of data, and the presentation of results. Examples are given and problems are solved using the Excel, Origin, Python and R software packages. In addition, programs in all four languages are made available to readers, allowing them to use them in analyzing and presenting the results of their own experiments. Subjects are treated at a level appropriate for undergraduate students in the natural sciences, but this book should also appeal to anyone whose work involves dealing with experimental results.

  12. Analysis of Dynamic Fracture Compliance Based on Poroelastic Theory - Part II: Results of Numerical and Experimental Tests

    Science.gov (United States)

    Wang, Ding; Ding, Pin-bo; Ba, Jing

    2018-03-01

    In Part I, a dynamic fracture compliance model (DFCM) was derived based on the poroelastic theory. The normal compliance of fractures is frequency-dependent and closely associated with the connectivity of porous media. In this paper, we first compare the DFCM with previous fractured media theories in the literature in a full frequency range. Furthermore, experimental tests are performed on synthetic rock specimens, and the DFCM is compared with the experimental data in the ultrasonic frequency band. Synthetic rock specimens saturated with water have more realistic mineral compositions and pore structures relative to previous works in comparison with natural reservoir rocks. The fracture/pore geometrical and physical parameters can be controlled to replicate approximately those of natural rocks. P- and S-wave anisotropy characteristics with different fracture and pore properties are calculated and numerical results are compared with experimental data. Although the measurement frequency is relatively high, the results of DFCM are appropriate for explaining the experimental data. The characteristic frequency of fluid pressure equilibration calculated based on the specimen parameters is not substantially less than the measurement frequency. In the dynamic fracture model, the wave-induced fluid flow behavior is an important factor for the fracture-wave interaction process, which differs from the models at the high-frequency limits, for instance, Hudson's un-relaxed model.

  13. Experimental models of transfusion-related acute lung injury.

    Science.gov (United States)

    Gilliss, Brian M; Looney, Mark R

    2011-01-01

    Transfusion-related acute lung injury (TRALI) is defined clinically as acute lung injury occurring within six hours of the transfusion of any blood product. It is the leading cause of transfusion-related death in the United States, but under-recognition and diagnostic uncertainty have limited clinical research to smaller case control studies. In this review we discuss the contribution of experimental models to the understanding of TRALI pathophysiology and potential therapeutic approaches. Experimental models suggest that TRALI occurs when a host, with a primed immune system, is exposed to an activating agent such as anti-leukocyte antibody or a biologic response modifier such as lysophosphatidylcholines. Recent work has suggested a critical role for platelets in antibody-based experimental models and identified potential therapeutic strategies for TRALI. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Experimental Models of Transfusion-Related Acute Lung Injury (TRALI)

    Science.gov (United States)

    Gilliss, Brian M.; Looney, Mark R.

    2010-01-01

    Transfusion-related acute lung injury (TRALI) is defined clinically as acute lung injury occurring within six hours of the transfusion of any blood product. It is the leading cause of transfusion-related death in the United States, but under-recognition and diagnostic uncertainty have limited clinical research to smaller case control studies. In this review we will discuss the contribution of experimental models to the understanding of TRALI pathophysiology and potential therapeutic approaches. Experimental models suggest that TRALI occurs when a host, with a primed immune system, is exposed to an activating agent such as anti-leukocyte antibody or a biologic response modifier such as lysophosphatidylcholines. Recent work has suggested a critical role for platelets in antibody-based experimental models and identified potential therapeutic strategies for TRALI. PMID:21134622

  15. Experimental Validation of a Dynamic Model for Lightweight Robots

    Directory of Open Access Journals (Sweden)

    Alessandro Gasparetto

    2013-03-01

    Full Text Available Nowadays, one of the main topics in robotics research is dynamic performance improvement by means of a lightening of the overall system structure. The effective motion and control of these lightweight robotic systems occurs with the use of suitable motion planning and control process. In order to do so, model-based approaches can be adopted by exploiting accurate dynamic models that take into account the inertial and elastic terms that are usually neglected in a heavy rigid link configuration. In this paper, an effective method for modelling spatial lightweight industrial robots based on an Equivalent Rigid Link System approach is considered from an experimental validation perspective. A dynamic simulator implementing the formulation is used and an experimental test-bench is set-up. Experimental tests are carried out with a benchmark L-shape mechanism.

  16. Modelling the spatial shape of nondiffracting beams: Experimental generation of Frozen Waves via computer generated holograms

    OpenAIRE

    Vieira, Tárcio A.; Zamboni-Rached, Michel; Gesualdi, Marcos R. R.

    2013-01-01

    In this paper we implement experimentally the spatial shape modelling of nondiffracting optical beams via computer generated holograms. The results reported here are the experimental confirmation of the so called Frozen Wave method, developed few years ago. Optical beams of this type can possess potential applications in optical tweezers, medicine, atom guiding, remote sensing, etc..

  17. Gastroprotective effect of Senecio candicans DC on experimental ulcer models.

    Science.gov (United States)

    Hariprasath, Lakshmanan; Raman, Jegadeesh; Nanjian, Raaman

    2012-03-06

    Senecio candicans DC (Asteraceae) is used as a remedy for gastric ulcer and stomach pain in the Nilgiris district, Tamil Nadu for which no scientific evidence exists. The present study was performed to evaluate the gastroprotective effects and acute oral toxicity of aqueous leaf extract of Senecio candicans (AESC) in experimental models. The antiulcerogenic activity of AESC was performed in two different ulcer models viz., pylorus-ligated model and ethanol-induced model using Wistar albino rats. Acute toxicity study was also performed to get information on the admissible dose for treatment of ulcer. Preliminary phytochemical screening of AESC was performed to find the active principles present, which are thus responsible for the antiulcerogenic activity. DPPH assay was performed to confirm the antioxidant activity of AESC. The acute toxicity study did not show any mortality up to 2500mg/kg b.w. of AESC. Both the ulcer models showed gastroprotective effect comparable to that of the standard Omeprazole. The results of antioxidant enzymes, histopathology sections, ATPase and mucus content of gastric secretion showed that several mechanisms are involved in the gastroprotective effect. The preliminary phytochemical screening revealed the presence of alkaloids, flavonoids and steroids in AESC. The DPPH assay confirmed the antioxidant activity of AESC. The traditional consumption of AESC for the treatment of gastric ulcer is thus true, the antioxidant constituents present in the extract plays a major role in the gastroprotective activity, but since Senecio species are known for the presence of pyrrolizidine alkaloids, a detailed study in future is required to describe the safe dose for a prolonged period. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  18. Experimental modeling of injectivity loss; Modelagem experimental da perda de injetividade

    Energy Technology Data Exchange (ETDEWEB)

    Bonato, Adriano Jose do Amaral Mello; Silva, Pedro Glauto de Farias e; Gomes, Vanessa Limeira Azevedo; Santos, Adriano dos [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2012-07-01

    Produced water reinjection, suspended particles are retained in the porous media causing formation damage and injectivity decline. In general the retention of the particles occurs near the side of injection, this fact occurs in most cases, due to the size exclusion. The modeling of filtration and the consequent formation damage is essential to the project management of water injection in oil reservoirs. Thus, mathematical models are studied to better predict the distribution of particles throughout the porous media and determine the parameters of adjustment to injectivity decline. Among these models, there is the classic model which consists in determining these parameters (coefficient of filtration and formation damage). The methodology used in modeling is given from the equations the mass conservation, kinetic particle retention, the modified Darcy equation and the function formation damage. This study aimed to improve experimental modeling, including development of software for acquisition and processing of experimental data, considering the variable number of pressure measurements along the sample. The software was developed using the Labview 2011 platform and allows the determination of relevant parameters to predict injectivity loss in water injection wells. Furthermore, based on the traditional model of filtration in porous media (including depth filtration and formation of the external plaster), the software was applied to predict injectivity loss in addition to the properties of the grout. Finally, the classical models for transporting suspensions and damage to the formation were observed. (author)

  19. 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.

  20. Revisiting Runoff Model Calibration: Airborne Snow Observatory Results Allow Improved Modeling Results

    Science.gov (United States)

    McGurk, B. J.; Painter, T. H.

    2014-12-01

    Deterministic snow accumulation and ablation simulation models are widely used by runoff managers throughout the world to predict runoff quantities and timing. Model fitting is typically based on matching modeled runoff volumes and timing with observed flow time series at a few points in the basin. In recent decades, sparse networks of point measurements of the mountain snowpacks have been available to compare with modeled snowpack, but the comparability of results from a snow sensor or course to model polygons of 5 to 50 sq. km is suspect. However, snowpack extent, depth, and derived snow water equivalent have been produced by the NASA/JPL Airborne Snow Observatory (ASO) mission for spring of 20013 and 2014 in the Tuolumne River basin above Hetch Hetchy Reservoir. These high-resolution snowpack data have exposed the weakness in a model calibration based on runoff alone. The U.S. Geological Survey's Precipitation Runoff Modeling System (PRMS) calibration that was based on 30-years of inflow to Hetch Hetchy produces reasonable inflow results, but modeled spatial snowpack location and water quantity diverged significantly from the weekly measurements made by ASO during the two ablation seasons. The reason is that the PRMS model has many flow paths, storages, and water transfer equations, and a calibrated outflow time series can be right for many wrong reasons. The addition of a detailed knowledge of snow extent and water content constrains the model so that it is a better representation of the actual watershed hydrology. The mechanics of recalibrating PRMS to the ASO measurements will be described, and comparisons in observed versus modeled flow for both a small subbasin and the entire Hetch Hetchy basin will be shown. The recalibrated model provided a bitter fit to the snowmelt recession, a key factor for water managers as they balance declining inflows with demand for power generation and ecosystem releases during the final months of snow melt runoff.

  1. Immersive visualization of dynamic CFD model results

    International Nuclear Information System (INIS)

    Comparato, J.R.; Ringel, K.L.; Heath, D.J.

    2004-01-01

    With immersive visualization the engineer has the means for vividly understanding problem causes and discovering opportunities to improve design. Software can generate an interactive world in which collaborators experience the results of complex mathematical simulations such as computational fluid dynamic (CFD) modeling. Such software, while providing unique benefits over traditional visualization techniques, presents special development challenges. The visualization of large quantities of data interactively requires both significant computational power and shrewd data management. On the computational front, commodity hardware is outperforming large workstations in graphical quality and frame rates. Also, 64-bit commodity computing shows promise in enabling interactive visualization of large datasets. Initial interactive transient visualization methods and examples are presented, as well as development trends in commodity hardware and clustering. Interactive, immersive visualization relies on relevant data being stored in active memory for fast response to user requests. For large or transient datasets, data management becomes a key issue. Techniques for dynamic data loading and data reduction are presented as means to increase visualization performance. (author)

  2. Linkage of PRA models. Phase 1, Results

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.L.; Knudsen, J.K.; Kelly, D.L.

    1995-12-01

    The goal of the Phase I work of the ``Linkage of PRA Models`` project was to postulate methods of providing guidance for US Nuclear Regulator Commission (NRC) personnel on the selection and usage of probabilistic risk assessment (PRA) models that are best suited to the analysis they are performing. In particular, methods and associated features are provided for (a) the selection of an appropriate PRA model for a particular analysis, (b) complementary evaluation tools for the analysis, and (c) a PRA model cross-referencing method. As part of this work, three areas adjoining ``linking`` analyses to PRA models were investigated: (a) the PRA models that are currently available, (b) the various types of analyses that are performed within the NRC, and (c) the difficulty in trying to provide a ``generic`` classification scheme to groups plants based upon a particular plant attribute.

  3. Engineering Glass Passivation Layers -Model Results

    Energy Technology Data Exchange (ETDEWEB)

    Skorski, Daniel C.; Ryan, Joseph V.; Strachan, Denis M.; Lepry, William C.

    2011-08-08

    The immobilization of radioactive waste into glass waste forms is a baseline process of nuclear waste management not only in the United States, but worldwide. The rate of radionuclide release from these glasses is a critical measure of the quality of the waste form. Over long-term tests and using extrapolations of ancient analogues, it has been shown that well designed glasses exhibit a dissolution rate that quickly decreases to a slow residual rate for the lifetime of the glass. The mechanistic cause of this decreased corrosion rate is a subject of debate, with one of the major theories suggesting that the decrease is caused by the formation of corrosion products in such a manner as to present a diffusion barrier on the surface of the glass. Although there is much evidence of this type of mechanism, there has been no attempt to engineer the effect to maximize the passivating qualities of the corrosion products. This study represents the first attempt to engineer the creation of passivating phases on the surface of glasses. Our approach utilizes interactions between the dissolving glass and elements from the disposal environment to create impermeable capping layers. By drawing from other corrosion studies in areas where passivation layers have been successfully engineered to protect the bulk material, we present here a report on mineral phases that are likely have a morphological tendency to encrust the surface of the glass. Our modeling has focused on using the AFCI glass system in a carbonate, sulfate, and phosphate rich environment. We evaluate the minerals predicted to form to determine the likelihood of the formation of a protective layer on the surface of the glass. We have also modeled individual ions in solutions vs. pH and the addition of aluminum and silicon. These results allow us to understand the pH and ion concentration dependence of mineral formation. We have determined that iron minerals are likely to form a complete incrustation layer and we plan

  4. Initial Experimental Results of a Laboratory Mini-Magnetosphere for Astronaut Protection

    Science.gov (United States)

    Bamford, R. A.; Bingham, R.; Gibson, K.; Thornton, A.; Bradford, J.; Hapgood, M.; Gargate, L.; Silva, L.; Norberg, C.; Todd, T.; Wilson, H.; Stamper, R.

    2007-12-01

    Radiation is a major scientific and technological challenge for manned missions to Mars. With an interplanetary flight time of months to years there is a high probability of Solar Energetic Particle events during the flight. Radiation damage to human tissue could result in acute sickness or death of the occupants of an unprotected spacecraft. Thus there is much interest in techniques to mitigate the effects of these events and of the exposure to cosmic rays. The experimental and modelling work presented here concerns one of several innovative "Active Shield" solutions being proposed [1]. The idea of generating an artificial magnetosphere to recreate the protective shield of the Earth's magnetic field for space craft travelling to the Moon or Mars was considered seriously in the 1960's during the Apollo era. With most of the space agencies around the world setting their sights returning to the Moon and then on to Mars, the idea of some sort of active field solution is experiencing a resurgence. Results from the laboratory experiment to determine the effectiveness of a mini-magnetosphere barrier to be able to expel a flowing energetic "solar wind" plasma will be presented. This is compared to a 3D hybrid simulation code that has been successfully compared to other astrophysical situations e.g. AMPTE artificial comet releases [2]. The experiment and modelling comparisons will demonstrate the scalability between the laboratory and astrophysical scale. [1] Adams, J.H. et al., "Revolutionary Concepts of Radiation Shielding for Human Exploration of Space", NASA/TM- 2005-213688, March 2005. [2] Gargate, L.; Bingham, R.; Fonseca, R. A.; Silva, L. O., "dHybrid: A massively parallel code for hybrid simulations of space plasmas", Computer Physics Communications, Volume 176, Issue 6, Pages 419-425, 15 March 2007, doi:10.1016/j.cpc.2006.11.013

  5. Experimental studies and modeling of an information embedded power system

    Science.gov (United States)

    Carullo, Stephen Paul

    This thesis develops a model of an electrical power system, with its inherent embedded communication system, for studying the characteristics of power system measurement errors due to communication delays. This model is referred to as an "information embedded power system" to emphasize the addition of a model of the communication system, that delivers measurements to a control center, to the standard model for the energy balance within the power system. These power system measurements are delivered across an Ethernet computer control network. An experimental platform was created in order to experimentally measure and characterize measurement delay errors (MDEs) in this information embedded power system. Several stochastic system models are developed, which are composed of both the physical infrastructure of the power system as well as the embedded computer network communication infrastructure. Both white noise and colored noise models are used to characterize MDEs. This type of analysis is an extension of traditional observability approaches, which usually only assume deterministic steady-state conditions in the power system and do not consider time delays in delivering measurements. The experimental platform is used to validate the developed model.

  6. Experimental studies on power transformer model winding provided with MOVs

    Directory of Open Access Journals (Sweden)

    G.H. Kusumadevi

    2017-05-01

    Full Text Available Surge voltage distribution across a HV transformer winding due to appearance of very fast rise time (rise time of order 1 μs transient voltages is highly non-uniform along the length of the winding for initial time instant of occurrence of surge. In order to achieve nearly uniform initial time instant voltage distribution along the length of the HV winding, investigations have been carried out on transformer model winding. By connecting similar type of metal oxide varistors across sections of HV transformer model winding, it is possible to improve initial time instant surge voltage distribution across length of the HV transformer winding. Transformer windings with α values 5.3, 9.5 and 19 have been analyzed. The experimental studies have been carried out using high speed oscilloscope of good accuracy. The initial time instant voltage distribution across sections of winding with MOV remains nearly uniform along length of the winding. Also results of fault diagnostics carried out with and without connection of MOVs across sections of winding are reported.

  7. Experimental investigation of statistical models describing distribution of counts

    International Nuclear Information System (INIS)

    Salma, I.; Zemplen-Papp, E.

    1992-01-01

    The binomial, Poisson and modified Poisson models which are used for describing the statistical nature of the distribution of counts are compared theoretically, and conclusions for application are considered. The validity of the Poisson and the modified Poisson statistical distribution for observing k events in a short time interval is investigated experimentally for various measuring times. The experiments to measure the influence of the significant radioactive decay were performed with 89 Y m (T 1/2 =16.06 s), using a multichannel analyser (4096 channels) in the multiscaling mode. According to the results, Poisson statistics describe the counting experiment for short measuring times (up to T=0.5T 1/2 ) and its application is recommended. However, analysis of the data demonstrated, with confidence, that for long measurements (T≥T 1/2 ) Poisson distribution is not valid and the modified Poisson function is preferable. The practical implications in calculating uncertainties and in optimizing the measuring time are discussed. Differences between the standard deviations evaluated on the basis of the Poisson and binomial models are especially significant for experiments with long measuring time (T/T 1/2 ≥2) and/or large detection efficiency (ε>0.30). Optimization of the measuring time for paired observations yields the same solution for either the binomial or the Poisson distribution. (orig.)

  8. Experimental and Numerical Modeling of Aerosol Delivery for Preterm Infants

    Directory of Open Access Journals (Sweden)

    Iñigo Aramendia

    2018-02-01

    Full Text Available Respiratory distress syndrome (RDS represents one of the major causes of mortality among preterm infants, and the best approach to treat it is an open research issue. The use of perfluorocarbons (PFC along with non-invasive respiratory support techniques has proven the usefulness of PFC as a complementary substance to achieve a more homogeneous surfactant distribution. The aim of this work was to study the inhaled particles generated by means of an intracorporeal inhalation catheter, evaluating the size and mass distribution of different PFC aerosols. In this article, we discuss different experiments with the PFC perfluorodecalin (PFD and FC75 with a driving pressure of 4–5 bar, evaluating properties such as the aerodynamic diameter (Da, since its value is directly linked to particle deposition in the lung. Furthermore, we develop a numerical model with computational fluid dynamics (CFD techniques. The computational results showed an accurate prediction of the airflow axial velocity at different downstream positions when compared with the data gathered from the real experiments. The numerical validation of the cumulative mass distribution for PFD particles also confirmed a closer match with the experimental data measured at the optimal distance of 60 mm from the catheter tip. In the case of FC75, the cumulative mass fraction for particles above 10 µm was considerable higher with a driving pressure of 5 bar. These numerical models could be a helpful tool to assist parametric studies of new non-invasive devices for the treatment of RDS in preterm infants.

  9. Instrumental and ethical aspects of experimental research with animal models

    Directory of Open Access Journals (Sweden)

    Mirian Watanabe

    2014-02-01

    Full Text Available Experimental animal models offer possibilities of physiology knowledge, pathogenesis of disease and action of drugs that are directly related to quality nursing care. This integrative review describes the current state of the instrumental and ethical aspects of experimental research with animal models, including the main recommendations of ethics committees that focus on animal welfare and raises questions about the impact of their findings in nursing care. Data show that, in Brazil, the progress in ethics for the use of animals for scientific purposes was consolidated with Law No. 11.794/2008 establishing ethical procedures, attending health, genetic and experimental parameters. The application of ethics in handling of animals for scientific and educational purposes and obtaining consistent and quality data brings unquestionable contributions to the nurse, as they offer subsidies to relate pathophysiological mechanisms and the clinical aspect on the patient.

  10. Modeling and Field Results from Seismic Stimulation

    International Nuclear Information System (INIS)

    Majer, E.; Pride, S.; Lo, W.; Daley, T.; Nakagawa, Seiji; Sposito, Garrison; Roberts, P.

    2006-01-01

    Modeling the effect of seismic stimulation employing Maxwell-Boltzmann theory shows that the important component of stimulation is mechanical rather than fluid pressure effects. Modeling using Biot theory (two phases) shows that the pressure effects diffuse too quickly to be of practical significance. Field data from actual stimulation will be shown to compare to theory

  11. Experimental Errors in QSAR Modeling Sets: What We Can Do and What We Cannot Do.

    Science.gov (United States)

    Zhao, Linlin; Wang, Wenyi; Sedykh, Alexander; Zhu, Hao

    2017-06-30

    Numerous chemical data sets have become available for quantitative structure-activity relationship (QSAR) modeling studies. However, the quality of different data sources may be different based on the nature of experimental protocols. Therefore, potential experimental errors in the modeling sets may lead to the development of poor QSAR models and further affect the predictions of new compounds. In this study, we explored the relationship between the ratio of questionable data in the modeling sets, which was obtained by simulating experimental errors, and the QSAR modeling performance. To this end, we used eight data sets (four continuous endpoints and four categorical endpoints) that have been extensively curated both in-house and by our collaborators to create over 1800 various QSAR models. Each data set was duplicated to create several new modeling sets with different ratios of simulated experimental errors (i.e., randomizing the activities of part of the compounds) in the modeling process. A fivefold cross-validation process was used to evaluate the modeling performance, which deteriorates when the ratio of experimental errors increases. All of the resulting models were also used to predict external sets of new compounds, which were excluded at the beginning of the modeling process. The modeling results showed that the compounds with relatively large prediction errors in cross-validation processes are likely to be those with simulated experimental errors. However, after removing a certain number of compounds with large prediction errors in the cross-validation process, the external predictions of new compounds did not show improvement. Our conclusion is that the QSAR predictions, especially consensus predictions, can identify compounds with potential experimental errors. But removing those compounds by the cross-validation procedure is not a reasonable means to improve model predictivity due to overfitting.

  12. 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

  13. Numerical and Experimental Modeling of the Static Response of ...

    African Journals Online (AJOL)

    This paper presents numerical and experimental modeling of the static response of simply supported thin-walled reinforced concrete box girder bridges. The work is executed to verify the validity of software developed by the authors for the finite strip analysis of continuous thin-walled box girder bridges and also to observe ...

  14. Experimental Analysis and Model Validation of an Opaque Ventilated Facade

    DEFF Research Database (Denmark)

    López, F. Peci; Jensen, Rasmus Lund; Heiselberg, Per

    2012-01-01

    Natural ventilation is a convenient way of reducing energy consumption in buildings. In this study an experimental module of an opaque ventilated façade (OVF) was built and tested for assessing its potential of supplying free ventilation and air preheating for the building. A numerical model was ...

  15. Active Photonic Crystal Switches: Modeling, Design and Experimental Characterization

    DEFF Research Database (Denmark)

    Heuck, Mikkel; Yu, Yi; Kristensen, Philip Trøst

    2013-01-01

    In this paper, we present recent progress in modeling, design, fabrication and experimental characterization of InP photonic crystal all-optical switches. Novel designs with increased flexibility and performance are presented, and their operation using high speed data signals is analyzed...

  16. An Interactive Multimedia Based Instruction in Experimental Modelling

    DEFF Research Database (Denmark)

    Knudsen, Morten; Nielsen, J.N.; Østergaard, J.

    1997-01-01

    A CD-ROM based interactive multimedia instruction in experimental modelling for Danish Engineering School teachers is described. The content is based on a new sensitivity approach for direct estimation of physical parameters in linear and nonlinear dynamic systems. The presentation is inspired...

  17. Novel sensors for food inspection modelling, fabrication and experimentation

    CERN Document Server

    Abdul Rahman, Mohd Syaifudin; Yu, Pak-Lam

    2014-01-01

    This book addresses presents recent developments of novel planar interdigital sensors for food inspection. It covers the fundamentals of sensors, their design, modelling and simulations, fabrications, characterizations, experimental investigations and analyses. This book will be useful for the engineers and researchers especially higher undergraduate, postgraduate students as well as practitioners working on the development of Electromagnetic Sensors.

  18. Endogenous opioid antagonism in physiological experimental pain models

    DEFF Research Database (Denmark)

    Werner, Mads U; Pereira, Manuel P; Andersen, Lars Peter H

    2015-01-01

    Opioid antagonists are pharmacological tools applied as an indirect measure to detect activation of the endogenous opioid system (EOS) in experimental pain models. The objective of this systematic review was to examine the effect of mu-opioid-receptor (MOR) antagonists in placebo-controlled, double...

  19. Capillary microreactors for lactic acid extraction: experimental and modelling study

    NARCIS (Netherlands)

    Susanti, Susanti; Winkelman, Jozef; Schuur, Boelo; Heeres, Hero; Yue, Jun

    2015-01-01

    Lactic acid is an important biobased chemical and, among others, is used for the production of poly-lactic acid. Down-stream processing using state of the art technology is energy intensive and leads to the formation of large amounts of salts. In this presentation, experimental and modeling studies

  20. Pruning Chinese trees : an experimental and modelling approach

    NARCIS (Netherlands)

    Zeng, Bo

    2001-01-01

    Pruning of trees, in which some branches are removed from the lower crown of a tree, has been extensively used in China in silvicultural management for many purposes. With an experimental and modelling approach, the effects of pruning on tree growth and on the harvest of plant material were studied.

  1. Two-phase flow experimental studies in micro-models

    NARCIS (Netherlands)

    Karadimitriou, N.K.

    2013-01-01

    The aim of this research project was to put more physics into theories of two-phase flow. The significance of including interfacial area as a separate variable in two-phase flow and transport models was investigated. In order to investigate experimentally the significance of the inclusion of

  2. Experimental validation of void fraction models for R410A air conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiaokui; Ding, Guoliang; Zhang, Ping; Han, Weizhe [Institute of Refrigeration and Cryogenics, Shanghai Jiaotong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Kasahara, Shinichi; Yamaguchi, Takahiro [Daikin Air-Conditioning R and D Laboratory, Ltd., 1304 Kanaoka-cho, Sakai, Osaka 591-8511 (Japan)

    2009-08-15

    This paper presents the combined void fraction models on the basis of flow pattern to choose suitable models for calculating the two-phase refrigerant mass of R410A air conditioners, and the model is validated experimentally. The existing single void fraction models are also evaluated experimentally. The Taitel-Dukler flow pattern map is recommended to use in the combined void fraction models. The results presented herein show that the calculated refrigerant mass using the combined void fraction models agrees relatively better with the measured refrigerant mass than that of the single void fraction models. T-B model (for intermittent flow) and Premoli model (for annular flow) are recommended for calculating the two-phase refrigerant mass in evaporator, and T-B model (for intermittent flow) and Harms model (for annular flow) are also indicated for calculating the two-phase refrigerant mass in condenser. (author)

  3. 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

  4. Pressurized thermal shocks: the JRC Ispra experimental test rig and analytical results

    International Nuclear Information System (INIS)

    Jovanovic, A.; Lucia, A.C.

    1990-01-01

    The paper tackles some issues of particular interest for the remanent (remaining) life prediction for the pressurized components exposed to pressurized thermal shock (PTS) loads, that have been tackled in analytical work performed in the framework of the MPA - JRC collaboration for the PTS experimental research at the JRC Ispra. These issues regard in general application of damage mechanics, fracture mechanics and artificial intelligence (including the treatment of uncertainties in the PTS analysis and experiments). The considered issues are essential for further understanding and modelling of the crack behaviour and of the component response in PTS conditions. In particular, the development of the FRAP preprocessor and development and implementation of a methodology for analysis of local non-stationary heat transfer coefficients during a PTS, have been explained more in detail. FRAP is used as a frontend, for the finite element code ABAQUS, for the heat transfer, stress and fracture mechanics analyses. The ABAQUS results are used further on, for the probabilistic fatigue crack growth analysis performed by the COVASTOL code. (author)

  5. Prediction of fatigue crack growth and experimental result on overload retardation

    International Nuclear Information System (INIS)

    Shibata, K.; Kawamura, T.; Hashimoto, M.

    1980-01-01

    The phenomena of crack growth retardation are frequently observed under variable amplitude or irregular loading fatigue tests. This paper describes a prediction method on crack growth retardation caused by an overload during fatigue loads. The prediction reported in this paper is performed by the following procedure using the yield strength and da/dN vs. ΔK relationship of the material. 1) Determination of the residual stress distribution caused by cyclic load and overload based on the Dugdale model. 2) Determination of the effective residual stress intensity factor and effective stress intensity range (ΔKsub(eff.)). 3) Prediction of the crack growth rate using ΔKsub(eff) and da/dN vs. ΔK relationship of the material. From the viewpoint to apply the prediction to a structural component, experiments have been carried out on steel pipes with an axial through thickness crack, which are subject to an overpressure during cyclic pressure. In the paper, the experimental results are compared with the prediction. (orig.)

  6. Atmosphere Behavior in Gas-Closed Mouse-Algal Systems: An Experimental and Modelling Study

    Science.gov (United States)

    Averner, M. M.; Moore, B., III; Bartholomew, I.; Wharton, R.

    1985-01-01

    A dual approach of mathematical modelling and laboratory experimentation aimed at examining the gas exchange characteristics of artificial animal/plant systems closed to the ambient atmosphere was initiated. The development of control techniques and management strategies for maintaining the atmospheric levels of carbon dioxide and oxygen at physiological levels is examined. A mathematical model simulating the atmospheric behavior in these systems was developed and an experimental gas closed system was constructed. These systems are described and preliminary results are presented.

  7. Experimental verification of mathematical model of the heat transfer in exhaust system

    Directory of Open Access Journals (Sweden)

    Petković Snežana

    2011-01-01

    Full Text Available A Catalyst convertor has maximal efficiency when it reaches working temperature. In a cold start phase efficiency of the catalyst is low and exhaust emissions have high level of air pollutants. The exhaust system optimization, in order to decrease time of achievement of the catalyst working temperature, caused reduction of the total vehicle emission. Implementation of mathematical models in development of exhaust systems decrease total costs and reduce time. Mathematical model has to be experimentally verified and calibrated, in order to be useful in the optimization process. Measurement installations have been developed and used for verification of the mathematical model of unsteady heat transfer in exhaust systems. Comparisons between experimental results and the mathematical model are presented in this paper. Based on obtained results, it can be concluded that there is a good agreement between the model and the experimental results.

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

    International Nuclear Information System (INIS)

    Stephan, G.

    1981-01-01

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

  9. Total laparoscopic gastrocystoplasty: experimental technique in a porcine model

    Directory of Open Access Journals (Sweden)

    Frederico R. Romero

    2007-02-01

    Full Text Available OBJECTIVE: Describe a unique simplified experimental technique for total laparoscopic gastrocystoplasty in a porcine model. MATERIAL AND METHODS: We performed laparoscopic gastrocystoplasty on 10 animals. The gastroepiploic arch was identified and carefully mobilized from its origin at the pylorus to the beginning of the previously demarcated gastric wedge. The gastric segment was resected with sharp dissection. Both gastric suturing and gastrovesical anastomosis were performed with absorbable running sutures. The complete procedure and stages of gastric dissection, gastric closure, and gastrovesical anastomosis were separately timed for each laparoscopic gastrocystoplasty. The end-result of the gastric suturing and the bladder augmentation were evaluated by fluoroscopy or endoscopy. RESULTS: Mean total operative time was 5.2 (range 3.5 - 8 hours: 84.5 (range 62 - 110 minutes for the gastric dissection, 56 (range 28 - 80 minutes for the gastric suturing, and 170.6 (range 70 to 200 minutes for the gastrovesical anastomosis. A cystogram showed a small leakage from the vesical anastomosis in the first two cases. No extravasation from gastric closure was observed in the postoperative gastrogram. CONCLUSIONS: Total laparoscopic gastrocystoplasty is a feasible but complex procedure that currently has limited clinical application. With the increasing use of laparoscopy in reconstructive surgery of the lower urinary tract, gastrocystoplasty may become an attractive option because of its potential advantages over techniques using small and large bowel segments.

  10. Establishment of a cerebral schistosomiasis experimental model in rabbits.

    Science.gov (United States)

    Wang, Peng; Wang, Dan; Chen, Shi-Jie; Wu, Ming-Can; Cheng, Xiang-Lin; Li, Jun-Chuan; Chen, Ting-Xuan; Zhu, Zhan-Sheng

    2011-04-01

    The present study aimed to establish a cerebral schistosomiasis model in rabbits, to provide a valuable tool for morphological analysis, clinical manifestation observation, as well as investigations into immunological reactions and pathogenesis of focal inflammatory reaction in neuroschistosomiasis (NS). Sixty New Zealand rabbits were randomly assigned into operation, sham-operation and normal groups. Rabbits in the operation group received direct injection of dead schistosome eggs into the brain, while their counterparts in the sham-operation group received saline injection. Rabbits in the normal group received no treatment. Base on the clinical manifestations, rabbits were sacrificed on days 3, 5, 7, 10, 20, and 30 post injection, and brain samples were sectioned and stained with hematoxylin-eosin. Sections were observed under the microscope. The rabbits in the operation group exhibited various neurological symptoms, including anorexy, partial and general seizures, and paralysis. The morphological analysis showed several schistosome eggs in the nervous tissue on day 3 post operation, with very mild inflammation. On days 7-10 post operation, several schistosome eggs were localized in proximity to red blood cells with many neutrophilic granulocytes and eosinophilic granulocytes around them. The schistosome eggs developed into the productive granuloma stage on days 14-20 post operation. On day 30, the schistosome eggs were found to be in the healing-by-fibrosis stage, and the granuloma area was replaced by fibrillary glia through astrocytosis. The sham-operation group and the normal group showed negative results. This method might be used to establish the cerebral schistosomiasis experimental model. Several factors need to be considered in establishing this model, such as the antigenic property of eggs, the time of scarification, and the clinical manifestations.

  11. Heterogeneity in Pure Microbial Systems: Experimental Measurements and Modeling.

    Science.gov (United States)

    González-Cabaleiro, Rebeca; Mitchell, Anca M; Smith, Wendy; Wipat, Anil; Ofiţeru, Irina D

    2017-01-01

    Cellular heterogeneity influences bioprocess performance in ways that until date are not completely elucidated. In order to account for this phenomenon in the design and operation of bioprocesses, reliable analytical and mathematical descriptions are required. We present an overview of the single cell analysis, and the mathematical modeling frameworks that have potential to be used in bioprocess control and optimization, in particular for microbial processes. In order to be suitable for bioprocess monitoring, experimental methods need to be high throughput and to require relatively short processing time. One such method used successfully under dynamic conditions is flow cytometry. Population balance and individual based models are suitable modeling options, the latter one having in particular a good potential to integrate the various data collected through experimentation. This will be highly beneficial for appropriate process design and scale up as a more rigorous approach may prevent a priori unwanted performance losses. It will also help progressing synthetic biology applications to industrial scale.

  12. Experimentally supported mathematical modeling of continuous baking processes

    DEFF Research Database (Denmark)

    Stenby Andresen, Mette

    and temperature) and control the process (air flow, temperature, and humidity) are therefore emphasized. The oven is furthermore designed to work outside the range of standard tunnel ovens, making it interesting for manufacturers of both baking products and baking equipment. A mathematical model describing......The scope of the PhD project was to increase knowledge on the process-to-product interactions in continuous tunnel ovens. The work has focused on five main objectives. These objectives cover development of new experimental equipment for pilot plant baking experiments, mathematical modeling of heat...... on mass transfer was examined through comparison of different modeling set-ups and experimental data. It was found that while the baking tray is likely to reduce the evaporation from the bottom surface, it is not correct to assume that no evaporation takes place at the covered surface. Parallel...

  13. Experimental assessment and modelling of nitrate utilisation for primary sludge.

    Science.gov (United States)

    Avcioğlu, E; Sözen, S; Orhon, D; van Loosdrecht, M C M

    2002-01-01

    Electron acceptor utilisation potential of filtered primary sludge under anoxic conditions was experimentally investigated. Major kinetic and stoichiometric parameters were assessed by means of model evaluation of nitrate profile obtained in batch reactors. ASM1, modified for endogenous decay, and ASM3 were used for model simulation. Both models provided consistent interpretation of experimental data. ASM1 yielded mu(H) and Y(HD) values of 6.1 d(-1) and 0.64 g cell COD(g COD)(-1) respectively for heterotrophic anoxic growth. The corresponding storage mechanism associated with ASM3 could be characterised by a k(STO) of 13 g COD (g COD d)(-1) and a Y(STO) of 0.78 g COD(g COD)(-1). The high k(STO) value suggests re-evaluation of the concept of readily biodegradable substrate as defined in ASM3 and tested in the study.

  14. Physics of human cooperation: experimental evidence and theoretical models

    Science.gov (United States)

    Sánchez, Angel

    2018-02-01

    In recent years, many physicists have used evolutionary game theory combined with a complex systems perspective in an attempt to understand social phenomena and challenges. Prominent among such phenomena is the issue of the emergence and sustainability of cooperation in a networked world of selfish or self-focused individuals. The vast majority of research done by physicists on these questions is theoretical, and is almost always posed in terms of agent-based models. Unfortunately, more often than not such models ignore a number of facts that are well established experimentally, and are thus rendered irrelevant to actual social applications. I here summarize some of the facts that any realistic model should incorporate and take into account, discuss important aspects underlying the relation between theory and experiments, and discuss future directions for research based on the available experimental knowledge.

  15. Coupled Michigan MHD - Rice Convection Model Results

    Science.gov (United States)

    de Zeeuw, D.; Sazykin, S.; Wolf, D.; Gombosi, T.; Powell, K.

    2002-12-01

    A new high performance Rice Convection Model (RCM) has been coupled to the adaptive-grid Michigan MHD model (BATSRUS). This fully coupled code allows us to self-consistently simulate the physics in the inner and middle magnetosphere. A study will be presented of the basic characteristics of the inner and middle magnetosphere in the context of a single coupled-code run for idealized storm inputs. The analysis will include region-2 currents, shielding of the inner magnetosphere, partial ring currents, pressure distribution, magnetic field inflation, and distribution of pV^gamma.

  16. Effects of tenoxicam in experimental corrosive esophagitis model.

    Science.gov (United States)

    Erbaş, M; Kiraz, H A; Küçük, A; Topaloğlu, N; Erdem, H; Şahin, H; Toman, H; Ozkan, M Turgut Alper

    2015-04-01

    Esophageal stricture, one of the important complications of corrosive esophagus, develops following edema and granulation tissue that forms during and after the inflammatory reactions. Tenoxicam, a non-steroid anti-inflammatory drug with a long half-life, prevents various leukocyte functions including phagocyte and histamine secretion by inhibiting prostaglandin synthesis and removes various oxygen radicals in the region of inflammation. We designed this as a histopathological study using tenoxicam in rats for which we created a corrosive esophagus model. After necessary authorizations were obtained, the study was performed in Çanakkale 18 Mart University experimental animal laboratory. Twenty-four Wistar albino rats, weighing 220-240 g, were used for the experiment. Experimental animals were randomized into three groups: tenoxicam group (group T, n:8), control group (group C, n:8), and sham group (group S, n:8). Tenoxicam 0.5 mg/kg/day was administered to animals in group T, where esophageal burn was developed experimentally, 5 mg/kg 0.9% NaCL was administered i.p. to rats in group C for 15 days, once in 24 hours. No procedure was applied to rats in group S. After 15 days, all animals were sacrificed under general anesthesia and their esophagi were extracted. As a result of histopathological evaluation, inflammation and fibroblast proliferation was not observed in rats in the sham group (group S). Intense inflammation was observed in six rats (6+/2-) in the control group, and fibroblast proliferation was observed as 5+/3-. And in treatment groups, inflammation was evaluated as 3+/5-, and fibroblast proliferation as 3+/5-. In our study, histopathologic damage score was higher in the control group (P < 0.005). We deduce that tenoxicam can be useful in the treatment of caustic esophageal injuries in the acute phase, but think that these drugs require further researches and clinical studies before routine clinical use. © 2014 International Society for Diseases

  17. Fuzzy logic analysis optimizations for pattern recognition - Implementation and experimental results

    Science.gov (United States)

    Hires, Matej; Habiballa, Hashim

    2017-07-01

    The article presents an practical results of optimization of the fuzzy logic analysis method for pattern recognition. The theoretical background of the proposed theory is shown in the former article extending the original fuzzy logic analysis method. This article shows the implementation and experimental verification of the approach.

  18. 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.

  19. The first experimental results on laser ion loading into superconducting ECR ion source at RIKEN

    CERN Document Server

    Arzumanyan, G M; Shirkov, G D; Yano, Y

    2002-01-01

    The first experimental results on ions and neutrals injection by means of laser ablation from metal targets into the RIKEN 18 GHz superconducting electron cyclotron resonance ion source (SC ECRIS) are presented. Pulsed aluminium ion currents up to Al sup 8 sup + were generated in the source. The difference in pulse shapes of various charge states of the extracted ion currents is registered

  20. Nuclear magnetic resonance. Present results and its application to renal pathology. Experimental study of hydronephrosis

    International Nuclear Information System (INIS)

    Bertrand, P.

    1987-01-01

    Results of proton nuclear magnetic resonance imaging and relaxation time measurement of experimental hydronephrosis in mice are presented. The study is preceded by a description of the physical principles underlying the phenomenon of nuclear magnetic resonance and of its biomedical applications and with a review of the clinical use of NMR imaging in renal pathology [fr

  1. 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

  2. At Odds: Reconciling Experimental and Theoretical Results in High School Physics

    Science.gov (United States)

    Gates, Joshua

    2009-01-01

    For this experiment, students are divided into 2 groups and presented with a static equilibrium force-balance problem to solve. One group works entirely experimentally and the other group theoretically, using Newton's laws. The groups present their seemingly dissimilar results and must reconcile them through discussion. (Contains 3 figures.)

  3. 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

  4. Experimental evaluation of the use of homogeneous and slip-flow two-phase dynamic models in evaporator modelling

    DEFF Research Database (Denmark)

    Jakobsen, Arne; Antonius, Jesper; Knudsen, Hans Jørgen Høgaard

    1999-01-01

    of the homogeneous model is approximately a factor 3 less than the charge calculated using the slip-flow model.The overall conclusion is that when one wants to investigate the dynamic behaviour due to the movement and amount of the refrigerant in the evaporator, then it is needed to use a slip-flow two-phase model...... shows that the dynamic response of the homogeneous model is too fast whereas the simulation results based on the slip-flow model agrees very well with the experimental results. Another difference in the results from the two types of models is the estimation of charge. The charge calculated by the use...

  5. Assessing incentive contracts for reducing residential electricity consumption: new experimental methods for new results

    International Nuclear Information System (INIS)

    Frachet, Laure

    2013-01-01

    Facing economic, political and environmental stakes, electricity providers are nowadays developing incentive tools, in order to reduce consumer's demand, particularly during peak demand periods. For residential customers, these tools can be tariffs (dynamic pricing of time-of-use tariffs), or informative devices or services (feedbacks on historical or real-time consumption, given on various media). They might go along with automation systems that can help cutting of some electric devices when needed. In order to evaluate the capacity of these settings among their customers, electricity utilities are developing quite a few studies, which are mainly field experiment often called pilots. During these pilots, demand response tools are implemented on a population sample. These long and expensive studies lid to quantitative and qualitative analysis. We have compiled about 40 of them and extract from this survey some generalizable teachings. We have shown what these results were and highlighted pilot programs' methodological limits. In order to propose a substitute to these heavy experimentations, we assessed the capacity or experimental economics. This relatively new discipline's objective is to evaluation the efficiency of institutions, like markets, but also to study what animate economic agents' behaviour, e.g. preferences, beliefs, cognitive biases, willingness to pay... We were also able to elaborate an experimental protocol dedicated to the evaluation of some demand response contracts' acceptability. The results collected during 14 experimental sessions gave us some innovative clues and insight on these contracts acceptability. But, beyond these results, we have demonstrated that even if experimental economics can't obviously be a substitute for field experiments, it can represent an interesting exploratory methodology. To sum up the experimental economics can take part of residential customers' behaviour understanding, performing

  6. Dermal uptake of phthalates from clothing: Comparison of model to human participant results

    DEFF Research Database (Denmark)

    Morrison, G. C.; Weschler, Charles J.; Beko, G.

    2017-01-01

    In this research, we extend a model of transdermal uptake of phthalates to include a layer of clothing. When compared with experimental results, this model better estimates dermal uptake of diethylphthalate and di-n-butylphthalate (DnBP) than a previous model. The model predictions are consistent...

  7. Graphical interpretation of numerical model results

    International Nuclear Information System (INIS)

    Drewes, D.R.

    1979-01-01

    Computer software has been developed to produce high quality graphical displays of data from a numerical grid model. The code uses an existing graphical display package (DISSPLA) and overcomes some of the problems of both line-printer output and traditional graphics. The software has been designed to be flexible enough to handle arbitrarily placed computation grids and a variety of display requirements

  8. Experimental Evaluation of Equivalent-Fluid Models for Melamine Foam

    Science.gov (United States)

    Allen, Albert R.; Schiller, Noah H.

    2016-01-01

    Melamine foam is a soft porous material commonly used in noise control applications. Many models exist to represent porous materials at various levels of fidelity. This work focuses on rigid frame equivalent fluid models, which represent the foam as a fluid with a complex speed of sound and density. There are several empirical models available to determine these frequency dependent parameters based on an estimate of the material flow resistivity. Alternatively, these properties can be experimentally educed using an impedance tube setup. Since vibroacoustic models are generally sensitive to these properties, this paper assesses the accuracy of several empirical models relative to impedance tube measurements collected with melamine foam samples. Diffuse field sound absorption measurements collected using large test articles in a laboratory are also compared with absorption predictions determined using model-based and measured foam properties. Melamine foam slabs of various thicknesses are considered.

  9. Experimental validation of a Bayesian model of visual acuity.

    LENUS (Irish Health Repository)

    Dalimier, Eugénie

    2009-01-01

    Based on standard procedures used in optometry clinics, we compare measurements of visual acuity for 10 subjects (11 eyes tested) in the presence of natural ocular aberrations and different degrees of induced defocus, with the predictions given by a Bayesian model customized with aberrometric data of the eye. The absolute predictions of the model, without any adjustment, show good agreement with the experimental data, in terms of correlation and absolute error. The efficiency of the model is discussed in comparison with image quality metrics and other customized visual process models. An analysis of the importance and customization of each stage of the model is also given; it stresses the potential high predictive power from precise modeling of ocular and neural transfer functions.

  10. Clean Sampling of an Englacial Conduit at Blood Falls, Antarctica - Some Experimental and Numerical Results

    Science.gov (United States)

    Kowalski, Julia; Francke, Gero; Feldmann, Marco; Espe, Clemens; Heinen, Dirk; Digel, Ilya; Clemens, Joachim; Schüller, Kai; Mikucki, Jill; Tulaczyk, Slawek M.; Pettit, Erin; Berry Lyons, W.; Dachwald, Bernd

    2017-04-01

    results of its deployment at Blood Falls. In contrast to conventional melting-probe applications, which can only melt vertically, the IceMole realized an oblique melting path to penetrate the englacial conduit. Experimental and numerical results on melting at oblique angles are rare. Besides reporting on the IceMole technology and the field deployment itself, we will compare and discuss the observed melting behavior with re-analysis results in the context of a recently developed numerical model. Finally, we will present our first steps in utilizing the model to infer on the ambient cryo-environment.

  11. New experimental results on the pion-nucleon interaction investigation in the resonance region

    Science.gov (United States)

    Sumachev, V. V.; Beloglazov, Yu. A.; Kovalev, A. I.; Kozlenko, N. G.; Kruglov, S. P.; Kulbardis, A. A.; Novinsky, D. V.; Trautman, V. Yu.; Alekseev, I. G.; Budkovsky, P. E.; Kanavets, V. P.; Koroleva, L. I.; Morozov, B. V.; Nesterov, V. M.; Ryltsov, V. V.; Sulimov, A. D.; Svirida, D. N.; Bazhanov, N. A.; Bunyatova, E. I.

    2002-03-01

    The spin rotation parameters A and R were measured for the elastic pion-proton scattering by the PNPI-ITEP collaboration in the D13 (1700), ΔS31(1900), ΔP33(1920) and ΔD33 (1940) resonances region. These resonances were absent in the set of partial wave analysis (PWA) of the Virginia Polytechnic Institute group (VPI), but was included in the tables of the Review of Particle Physics. The main goal of the experimental program was to resolve the current PWA’s disagreement in spin rotation parameters value predictions. Simultaneously with A and R the polarization parameter P was measured with the purpose to improve the experimental data base and estimate the experimental systematic errors. Our results for spin rotation parameters A and | R| are in agreement with PWA VPI predictions.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Experimental model of severe acute pancreatitis in rabbits Modelo experimental de pancreatite aguda grave em coelhos

    Directory of Open Access Journals (Sweden)

    Alberto Goldenberg

    2007-10-01

    Full Text Available PURPOSE: To develop an experimental model of severe acute pancreatitis in rabbits through a pancreatic ductal injection of sodium taurocholate. METHODS: Twenty-four albino rabbits of the New Zealand lineage were distributed into four groups of six animals (A, B, C and S. The rabbits of three experimental groups (A, B and C were submitted to a laparatomy and received a pancreatic ductal injection of 1ml/kg sodium taurocholate 5%. Also, they were submitted to further laparatomies after 4h, 8h and 12h, respectively. The control group (S was subdivided into two groups of three animals: in subgroup S1 only the pancreatic duct catheterization was performed whereas in subgroup S2 the pancreatic duct catheterization as well as an injection of 1ml/kg physiologic solution 0.9% were carried out. After 12 hours, the rabbits were evaluated. In the re-intervention, blood was collected to determine the amylasemia and a pancreatectomy was carried out to investigate interstitial infiltration, steatonecrosis and necrosis of the organ, using an optical microscope. RESULTS: There was an elevation of amylase in all groups thus proving the existence of acute pancreatitis. The size of the interlobular septum increased progressively with a greater variation between group S1 (0.13 and group C (0. 53 (p=0.035. While all the animals in group A exhibited focal cellular necrosis, it was more intense in the rabbits of group B and culminated with a high proportion of severe pancreatic necrosis in group C animals. The difference in the intensity of cellular necrosis showed statistic significance (p=0.001. CONCLUSION: The proposed experimental model demonstrated its reproducibility and effectiveness in producing severe acute pancreatitis in rabbits.OBJETIVO: Desenvolver modelo experimental de pancreatite aguda grave em coelhos por meio da injeção de taurocolato de sódio no ducto pancreático. MÉTODOS: Vinte e quatro coelhos albinos da linhagem Nova Zelândia foram distribu

  14. Ignalina NPP Safety Analysis: Models and Results

    International Nuclear Information System (INIS)

    Uspuras, E.

    1999-01-01

    Research directions, linked to safety assessment of the Ignalina NPP, of the scientific safety analysis group are presented: Thermal-hydraulic analysis of accidents and operational transients; Thermal-hydraulic assessment of Ignalina NPP Accident Localization System and other compartments; Structural analysis of plant components, piping and other parts of Main Circulation Circuit; Assessment of RBMK-1500 reactor core and other. Models and main works carried out last year are described. (author)

  15. Modeling clicks beyond the first result page

    NARCIS (Netherlands)

    Chuklin, A.; Serdyukov, P.; de Rijke, M.

    2013-01-01

    Most modern web search engines yield a list of documents of a fixed length (usually 10) in response to a user query. The next ten search results are usually available in one click. These documents either replace the current result page or are appended to the end. Hence, in order to examine more

  16. 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

  17. Transvaginal ultrasound ovarian diathermy: sheep as an experimental model

    Directory of Open Access Journals (Sweden)

    Pimentel Anita M

    2012-01-01

    Full Text Available Abstract Background Some techniques of transvaginal ovarian drilling have been previously described. Nevertheless a monopolar transvaginal ovarian cauterization, that use the expertise and safety of transvaginal puncture for oocyte captation seems to be an easier and feasible approach. The aim of this study was to develop a minimally invasive ovarian cauterization technique under transvaginal ultrasound control, and to evaluate the safety of the transvaginal ovarian monopolar cauterization, female sheep at reproductive age were used as an experimental model. Findings An experimental study was performed in a university research center. Seventeen female sheep (15 Corriedale e 2 Suffolk in reproductive age were submitted to transvaginal ovarian cauterization with a monopolar Valleylab Force 2 electrocautery. Macroscopic and microscopic lesions were assessed. Ovarian size were 1.31 cm2 ± 0,43 (Corriedale and 3.41 cm2 ± 0,64 (Suffolk. From 30 ovaries from Corriedale sheep punctured, only 3 were cauterized, presenting macroscopic and typical microscopic lesion. In the Suffolk sheep group, only one ovary was cauterized. No lesion could be found in the needle path. Conclusions This is the first experimental animal model described for ovarian cauterization needle guided by transvaginal ultrasound. The sheep does not seem to be the ideal animal model to study this technique. Another animal model, whose ovaries are better identified by transvaginal ultrasound should be sought for this technique, theoretically less invasive, before it could be offered safely to women with polycystic ovary syndrome.

  18. Establishing experimental model of human internal carotid artery siphon segment in canine common carotid artery

    International Nuclear Information System (INIS)

    Cui Xuee; Li Minghua; Wang Yongli; Cheng Yingsheng; Li Wenbin

    2005-01-01

    Objective: To study the feasibility of establishing experimental model of human internal carotid artery siphon segment in canine common carotid artery (CCA) by end-to-end anastomoses of one side common carotid artery segment with the other side common carotid artery. Methods: Surgical techniques were used to make siphon model in 8 canines. One side CCA was taken as the parent artery and anastomosing with the cut off contra-lateral CCA segment which has passed through within the S-shaped glass tube. Two weeks after the creation of models angiography showed the model siphons were patent. Results: Experimental models of human internal carotid artery siphon segment were successfully made in all 8 dogs. Conclusions: It is practically feasible to establish experimental canine common carotid artery models of siphon segment simulating human internal carotid artery. (authors)

  19. Evolution au cours du temps d'un grain de catalyseur d'hydrodémétallisation : module et simulation numérique de résultats expérimentaux Evolution in Time of a Hydrodemetallization Catalyst Pellet: Modeling and Numerical Simulation of Experimental Results

    Directory of Open Access Journals (Sweden)

    Bourseau P.

    2006-11-01

    Full Text Available On propose un modèle de désactivation lente d'un catalyseur de répartition poreuse bimodale par dépôt solide d'un des produits de réaction dans les pores. Le dépôt solide catalyse également la réaction, la désactivation s'effectuant par diminution de la surface spécifique et bouchage progressif des pores. Le modèle prend en compte les limitations diffusionnelles existant à l'intérieur du grain de catalyseur. Ce modèle utilise une représentation géométrique particulière des pores, et une loi de diffusion tenant compte de la variation des paramètres texturaux au cours du temps. Il suppose la connaissance expérimentale de la surface spécifique totale et de la distribution du volume poreux en fonction du diamètre des pores. Ce modèle a permis de retrouver avec un très bon accord quantitatif la courbe de captation des métaux (Ni + V en fonction du temps de fonctionnement obtenue expérimentalement pour un catalyseur d'hydrodémétallisation (HDM sur un pétrole brut de Boscan désasphalté. Il permet en outre de prédire la durée de vie et le taux d'occupation final du volume poreux d'un catalyseur d'HDM modèle. A model is proposed for the slow deactivation of a catalyst with a bimodal pore distribution by a solid deposit of one of the reaction products inside the pores. The solid deposit is by itself a catalyst for the reaction, with deactivation resulting from the progressive decrease of specific area and blockage of the pores. The model takes Intragranular diffusional limitations into account. This model uses an original geometric representation of the pores together with a diffusion law incorporating the variation of textural parameters in time. It requires the experimental determination of the total specific area and of pore volume distribution as a function of pore diameter. Numerical simulations with this model provided a very good quantitative fit with the capture curve for metals (Ni + V as a function of

  20. Double piezoelectric energy harvesting cell: modeling and experimental verification

    Science.gov (United States)

    Wang, Xianfeng; Shi, Zhifei

    2017-06-01

    In this paper, a novel energy transducer named double piezoelectric energy harvesting cell (DPEHC) consisting of two flex-compressive piezoelectric energy harvesting cells (F-C PEHCs) is proposed. At the very beginning, two F-C PEHCs, a kind of cymbal type energy transducer, are assembled together sharing the same end just in order to be placed steady. However, throughout an open-circuit voltage test, additional energy harvesting performance of the DPEHC prototype appears. Taking the interaction between the two F-C PEHCs into account, a mechanical model for analyzing the DPEHC is established. The electric output of the DPEHC under harmonic excitation is obtained theoretically and verified experimentally, and good agreement is found. In addition, as an inverse problem, the method for identifying the key mechanical parameters of the DPEHC is recommended. Finally, the additional energy harvesting performance of the DPEHC is quantitatively discussed. Numerical results show that the additional energy harvesting performance of the DPEHC is correlated with the key mechanical parameters of the DPEHC. For the present DPEHC prototype, the energy harvesting addition is over 400% compared with two independent F-C PEHCs under the same load condition.

  1. Experimental system model of a primary active fluid

    International Nuclear Information System (INIS)

    Deseigne, Julien

    2010-01-01

    Collective motion, such as flocks of birds or shoals of fish, is ubiquitous in nature. Such fundamentally out-of-equilibrium phenomena may be described with the new conceptual background of polar active matter, a system of polar particles which enables to use provided energy in order to move in their own directions. A 2D experimental system of vibrated polar disks that interact only by contact has been set up. These disks behave as random walkers, whose trajectories are characterized by a persistence length greater than their size and controlled by the angular fluctuations of their polarity. The interplay between the hard-core repulsion and the persistence of the motion leads to complex alignment modes. For instance, only 10 pc of the binary collisions correspond to an effective ferromagnetic alignment. Yet, spontaneous collective motion inside the system characterized by giant fluctuations of density have been observed. These results reveal the robustness of the polar order observed in theoretical and numerical models of 2D polar active matter on substrate

  2. Modeling experimental plasma diagnostics in the FLASH code: proton radiography

    Science.gov (United States)

    Flocke, Norbert; Weide, Klaus; Feister, Scott; Tzeferacos, Petros; Lamb, Donald

    2017-10-01

    Proton radiography is an important diagnostic tool for laser plasma experiments and for studying magnetized plasmas. We describe a new synthetic proton radiography diagnostic recently implemented into the FLASH code. FLASH is an open source, finite-volume Eulerian, spatially adaptive radiation hydrodynamics and magneto-hydrodynamics code that incorporates capabilities for a broad range of physical processes. Proton radiography is modeled through the use of the (relativistic) Lorentz force equation governing the motion of protons through 3D domains. Both instantaneous (one time step) and time-resolved (over many time steps) proton radiography can be simulated. The code module is also equipped with several different setup options (beam structure and detector screen placements) to reproduce a large variety of experimental proton radiography designs. FLASH's proton radiography diagnostic unit can be used either during runtime or in post-processing of simulation results. FLASH is publicly available at flash.uchicago.edu. U.S. DOE NNSA, U.S. DOE NNSA ASC, U.S. DOE Office of Science and NSF.

  3. Spherical sector model for describing the experimental small-angle neutron scattering data for dendrimers

    International Nuclear Information System (INIS)

    Rogachev, A. V.; Cherny, A. Yu.; Ozerin, A. N.; Gordeliy, V. I.; Kuklin, A. I.

    2007-01-01

    A new model for interpreting the results of small-angle neutron scattering from dendrimer solutions is proposed. The mathematical description is given and the theoretical small-angle scattering curves for spherical sectors with different parameters are presented. It is shown that the model proposed is in good agreement with the experimental results. Comparison of the experimental small-angle neutron scattering curves for polyallylcarbosilane dendrimers of the ninth generation with model scattering curves suggests that the inner dendrimer sphere is permeable to a solvent whose density is lower than the density of the solvent beyond the dendrimer by a factor of at least 2

  4. Error modelling and experimental validation of a planar 3-PPR parallel manipulator with joint clearances

    DEFF Research Database (Denmark)

    Wu, Guanglei; Bai, Shaoping; Kepler, Jørgen Asbøl

    2012-01-01

    This paper deals with the error modelling and analysis of a 3-PPR planar parallel manipulator with joint clearances. The kinematics and the Cartesian workspace of the manipulator are analyzed. An error model is established with considerations of both configuration errors and joint clearances. Using...... this model, the upper bounds and distributions of the pose errors for this manipulator are established. The results are compared with experimental measurements and show the effectiveness of the error prediction model....

  5. Experimentation with GRACE, the Generic Model of Emotions For Computational Applications

    Science.gov (United States)

    Dang, Thi-Hai-Ha; Duhaut, Dominique

    2009-03-01

    In this paper, we present a model of emotions that we proposed in EmotiRob project. First of all, we make a comparison of recent models of emotions and show that our model is generic in basing on the theories of emotions of Ortony et al., of Lazarus, of Scherer and then the personality theory of Meyers-Brigg and Meyers. Then, we present our experimentation with the first instance of the model and its result to validate our work.

  6. MHD seawater thruster performance: A comparison of predictions with experimental results from a two Tesla test facility

    Energy Technology Data Exchange (ETDEWEB)

    Picologlou, B. F.; Doss, E. D.; Geyer, H. K. [Argonne National Lab., IL (United States); Sikes, W. C.; Ranellone, R. F. [Newport News Shipbuilding and Dry Dock Co., VA (United States)

    1992-01-01

    A two Tesla test facility was designed, built, and operated to investigate the performance of magnetohydrodynamic (MHD) seawater thrusters. The results of this investigation are used to validate a design oriented MHD thruster performance computer code. The thruster performance code consists of a one-dimensional MHD hydrodynamic model coupled to a two-dimensional electrical model. The code includes major loss mechanisms affecting the performance of the thruster. Among these losses are the joule dissipation losses, frictional losses, electrical end losses, and single electrode potential losses. The facility test loop, its components, and their design are presented in detail. Additionally, the test matrix and its rationale are discussed. Representative experimental results of the test program are presented, and are compared to pretest computer model predictions. Good agreement between predicted and measured data has served to validate the thruster performance computer models.

  7. Experimental animal data and modeling of late somatic effects

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1988-01-01

    This section is restricted to radiation-induced life shortening and cancer and mainly to studies with external radiation. The emphasis will be on the experimental data that are available and the experimental systems that could provide the type of data with which to either formulate or test models. Genetic effects which are of concern are not discussed in this section. Experimental animal radiation studies fall into those that establish general principles and those that demonstrate mechanisms. General principles include the influence of dose, radiation quality, dose rate, fractionation, protraction and such biological factors as age and gender. The influence of these factors are considered as general principles because they are independent, at least qualitatively, of the species studied. For example, if an increase in the LET of the radiation causes an increased effectiveness in cancer induction in a mouse a comparable increase in effectiveness can be expected in humans. Thus, models, whether empirical or mechanistic, formulated from experimental animal data should be generally applicable

  8. Experimental animal data and modeling of late somatic effects

    Energy Technology Data Exchange (ETDEWEB)

    Fry, R.J.M.

    1988-01-01

    This section is restricted to radiation-induced life shortening and cancer and mainly to studies with external radiation. The emphasis will be on the experimental data that are available and the experimental systems that could provide the type of data with which to either formulate or test models. Genetic effects which are of concern are not discussed in this section. Experimental animal radiation studies fall into those that establish general principles and those that demonstrate mechanisms. General principles include the influence of dose, radiation quality, dose rate, fractionation, protraction and such biological factors as age and gender. The influence of these factors are considered as general principles because they are independent, at least qualitatively, of the species studied. For example, if an increase in the LET of the radiation causes an increased effectiveness in cancer induction in a mouse a comparable increase in effectiveness can be expected in humans. Thus, models, whether empirical or mechanistic, formulated from experimental animal data should be generally applicable.

  9. Maneuver simulation model of an experimental hovercraft for the Antarctic

    Science.gov (United States)

    Murao, Rinichi

    Results of an investigation of a hovercraft model designed for Antarctic conditions are presented. The buoyancy characteristics, the propellant control system, and simulation model control are examined. An ACV (air cushion vehicle) model of the hovercraft is used to examine the flexibility and friction of the skirt. Simulation results are presented which show the performance of the hovercraft.

  10. Some Experimental and Simulation Results on the Dynamic Behaviour of Spur and Helical Geared Transmissions with Journal Bearings

    Directory of Open Access Journals (Sweden)

    R. Fargère

    2012-01-01

    Full Text Available Some interactions between the dynamic and tribological behaviour of geared transmissions are examined, and a number of experimental and simulation results are compared. A model is introduced which incorporates most of the possible interactions between gears, shafts and hydrodynamic journal bearings. It combines (i a specific element for wide-faced gears that includes the normal contact conditions between actual mating teeth, that is, with tooth shape deviations and mounting errors, (ii shaft finite elements, and (iii the external forces generated by journal bearings determined by directly solving Reynolds' equation. The simulation results are compared with the measurement obtained on a high-precision test rig with single-stage spur and helical gears supported by hydrodynamic journal bearings. The experimental and simulation results compare well thus validating the simulation strategy both at the global and local scales.

  11. MRI monitoring of experimental cerebral ischaemia: comparison of two models

    International Nuclear Information System (INIS)

    Forsting, M.; Reith, W.; Doerfler, A.; Meyding-Lamade, U.; Sartor, K.

    1994-01-01

    The aim of this study was to compare two minimally invasive rat models of focal ischaemic stroke as to their ability to simulate clinical stroke reproducibly. In one model a focal infarct was induced using the photochemical Rose Bengal technique. The second model was based on transvascular occlusion of the middle cerebral artery using a cervical approach. In all animals we performed MRI at different times with two different paramagnetic contrast agents. The time course of blood-brain-barrier disruption in the Rose Bengal model differed entirely from that in human brain ischaemia. The experimental stroke showed marked contrast enhancement in the first hour after the onset of ischaemia. On the other hand, the MRI changes in the suture occlusion model were very similar to the changes observed in human brain ischaemia: no early disruption of the blood-brain-barrier and increased T2-signal 4-6 h after the onset of stroke. (orig.)

  12. COMPUTATIONAL AND EXPERIMENTAL MODELING OF SLURRY BUBBLE COLUMN REACTORS

    Energy Technology Data Exchange (ETDEWEB)

    Paul Lam; Dimitri Gidaspow

    2000-09-01

    The objective if this study was to develop a predictive experimentally verified computational fluid dynamics (CFD) model for gas-liquid-solid flow. A three dimensional transient computer code for the coupled Navier-Stokes equations for each phase was developed. The principal input into the model is the viscosity of the particulate phase which was determined from a measurement of the random kinetic energy of the 800 micron glass beads and a Brookfield viscometer. The computed time averaged particle velocities and concentrations agree with PIV measurements of velocities and concentrations, obtained using a combination of gamma-ray and X-ray densitometers, in a slurry bubble column, operated in the bubbly-coalesced fluidization regime with continuous flow of water. Both the experiment and the simulation show a down-flow of particles in the center of the column and up-flow near the walls and nearly uniform particle concentration. Normal and shear Reynolds stresses were constructed from the computed instantaneous particle velocities. The PIV measurement and the simulation produced instantaneous particle velocities. The PIV measurement and the simulation produced similar nearly flat horizontal profiles of turbulent kinetic energy of particles. This phase of the work was presented at the Chemical Reaction Engineering VIII: Computational Fluid Dynamics, August 6-11, 2000 in Quebec City, Canada. To understand turbulence in risers, measurements were done in the IIT riser with 530 micron glass beads using a PIV technique. The results together with simulations will be presented at the annual meeting of AIChE in November 2000.

  13. Peltier cells as temperature control elements: Experimental characterization and modeling

    International Nuclear Information System (INIS)

    Mannella, Gianluca A.; La Carrubba, Vincenzo; Brucato, Valerio

    2014-01-01

    The use of Peltier cells to realize compact and precise temperature controlled devices is under continuous extension in recent years. In order to support the design of temperature control systems, a simplified modeling of heat transfer dynamics for thermoelectric devices is presented. By following a macroscopic approach, the heat flux removed at the cold side of Peltier cell can be expressed as Q . c =γ(T c −T c eq ), where γ is a coefficient dependent on the electric current, T c and T c eq are the actual and steady state cold side temperature, respectively. On the other hand, a microscopic modeling approach was pursued via finite element analysis software packages. To validate the models, an experimental apparatus was designed and build-up, consisting in a sample vial with the surfaces in direct contact with Peltier cells. Both modeling approaches led to reliable prediction of transient and steady state sample temperature. -- Highlights: • Simplified modeling of heat transfer dynamics in Peltier cells. • Coupled macroscopic and microscopic approach. • Experimental apparatus: temperature control of a sample vial. • Both modeling approaches predict accurately the transient and steady state sample temperature

  14. WWER reactor fuel performance, modelling and experimental support. Proceedings

    International Nuclear Information System (INIS)

    Stefanova, S.; Chantoin, P.; Kolev, I.

    1994-01-01

    This publication is a compilation of 36 papers presented at the International Seminar on WWER Reactor Fuel Performance, Modelling and Experimental Support, organised by the Institute for Nuclear Research and Nuclear Energy (BG), in cooperation with the International Atomic Energy Agency. The Seminar was attended by 76 participants from 16 countries, including representatives of all major Russian plants and institutions responsible for WWER reactor fuel manufacturing, design and research. The reports are grouped in four chapters: 1) WWER Fuel Performance and Economics: Status and Improvement Prospects: 2) WWER Fuel Behaviour Modelling and Experimental Support; 3) Licensing of WWER Fuel and Fuel Analysis Codes; 4) Spent Fuel of WWER Plants. The reports from the corresponding four panel discussion sessions are also included. All individual papers are recorded in INIS as separate items

  15. Desorption of plutonium from montmorillonite: An experimental and modeling study

    Science.gov (United States)

    Begg, James D.; Zavarin, Mavrik; Kersting, Annie B.

    2017-01-01

    Desorption of plutonium (Pu) will likely control the extent to which it is transported by mineral colloids. We evaluated the adsorption/desorption behavior of Pu on SWy-1 montmorillonite colloids at pH 4, pH 6, and pH 8 using batch adsorption and flow cell desorption experiments. After 21 days adsorption, Pu(IV) affinity for montmorillonite displayed a pH dependency, with Kd values highest at pH 4 and lowest at pH 8. The pH 8 experiment was further allowed to equilibrate for 6 months and showed an increase in Kd, indicating that true sorption equilibrium was not achieved within the first 21 days. For the desorption experiments, aliquots of the sorption suspensions were placed in a flow cell, and Pu-free solutions were then pumped through the cell for a period of 12 days. Changes in influent solution flow rate were used to investigate the kinetics of Pu desorption and demonstrated that it was rate-limited over the experimental timescales. At the end of the 12-day flow cell experiments, the extent of desorption was again pH dependent, with pH 8 > pH 6 > pH 4. Further, at pH 8, less Pu was desorbed after an adsorption contact time of 6 months than after a contact time of 21 days, consistent with an aging of Pu on the clay surface. A conceptual model for Pu adsorption/desorption that incorporated known surface-mediated Pu redox reactions was used to fit the experimental data. The resulting rate constants indicated processes occurring on timescales of months and even years which may, in part, explain observations of clay colloid-facilitated Pu transport on decadal timescales. Importantly, however, our results also imply that migration of Pu adsorbed to montmorillonite colloids at long (50-100 year) timescales under oxic conditions may not be possible without considering additional phenomena, such as co-precipitation.

  16. Application of a LiFePO4 Battery Energy Storage System to Primary Frequency Control: Simulations and Experimental Results

    Directory of Open Access Journals (Sweden)

    Fabio Massimo Gatta

    2016-10-01

    Full Text Available This paper presents an experimental application of LiFePO4 battery energy storage systems (BESSs to primary frequency control, currently being performed by Terna, the Italian transmission system operator (TSO. BESS performance in the primary frequency control role was evaluated by means of a simplified electrical-thermal circuit model, taking into account also the BESS auxiliary consumptions, coupled with a cycle-life model, in order to assess the expected life of the BESS. Numerical simulations have been carried out considering the system response to real frequency measurements taken in Italy, spanning a whole year; a parametric study taking into account different values of governor droop and of BESS charge/discharge rates (C-rates was also performed. Simulations, fully validated by experimental results obtained thus far, evidenced a severe trade-off between expected lifetime and overall efficiency, which significantly restricts the choice of operating parameters for frequency control.

  17. Modelling and experimental studies on a mixed-mode natural convection solar crop-dryer

    Energy Technology Data Exchange (ETDEWEB)

    Forson, F.K. [Department of Mechanical Engineering, Kwame Nkrumah University of Science and Technology, Kumasi (Ghana); Nazha, M.A.A.; Rajakaruna, H. [School of Engineering and Technology, De Montfort University, Queens Building, Leicester LE1 9BH (United Kingdom)

    2007-03-15

    A mathematical model for drying agricultural products in a mixed-mode natural convection solar crop dryer (MNCSCD) using a single-pass double-duct solar air-heater (SPDDSAH) is presented. The model was developed in parallel with experimental work. The model comprises the air-heating process model, the drying model and the technical performance criteria model. The governing equations of the drying air temperature and humidity ratio; the material temperature and its moisture content; and performance criteria indicators are derived. The model requires the solution of a number of interrelated non-linear equations and a set of simultaneous differential equations. Results from experimental studies used for generating the required experimental data for validating the model are presented. Results of simulation runs using the model are presented and compared with the experimental data. It is shown that the model can predict the performance of the MNCSCD fairly accurately and therefore can be used as a design tool for prototype development. (author)

  18. Experimental and modeling studies of clay/polydicyclopentadiene resin nanocomposites

    Science.gov (United States)

    Yoonessi, Mitra

    Hybrid organic-inorganic nanocomposites have received considerable attention during the last five years due to their unexpected properties. This work incorporated nanodispersed organically modified montmorillonite clay into polydicyclopentadiene resin matrices. Montmorillonite consists of 1 nm platelet sheets with a 2:1 structure, consisting of an alumina octahedral layer sandwiched between two silica tetrahedral layers. The relative weak forces between platelets allow small molecules like water, solvents and monomers as well as polymers, to enter into the interlayer spacings between the platelet sheets. In-situ polymerization of highly delaminated clay/dicyclopentadiene (DCPD) dispersions was used to prepare clay/polydicyclopentadiene (polyDCPD) nanocomposites. Highly delaminated composites were characterized using X-ray diffraction, X-ray scattering and high resolution TEM. Composites with 0.5--1 weight percent of clay had higher Tg values and flexural moduli. The flow properties of the organically-modified montmorillonite/DCPD liquid dispersions were examined using a co-rotating viscometer. The dispersions with clay concentrations higher than 0.5wt% clay in DCPD showed thixotropic flow behavior. Small angle neutron scattering (SANS) experiments were performed to obtain anisotropic scattering of highly delaminated clay in DCPD due to the orientation of clay platelets and tactoids in the shear field. No anisotropic scattering was observed. The reason for this unexpected result is not yet understood. Highly delaminated organically-modified clay composites were examined using small angle neutron scattering (SANS) and ultra small angle neutron scattering (USANS). The SANS data from 0.5, 1 and 2wt% clay/polyDCPD composites with 2 different types of clay were fitted to the stacked disk model. The average number of clay layers per tactoid was predicted by fitting the experimental data to the stacked disk model. Extensive high-resolution TEM analyses were performed on

  19. Experimental Models of Transfusion-Related Acute Lung Injury (TRALI)

    OpenAIRE

    Gilliss, Brian M.; Looney, Mark R.

    2011-01-01

    Transfusion-related acute lung injury (TRALI) is defined clinically as acute lung injury occurring within six hours of the transfusion of any blood product. It is the leading cause of transfusion-related death in the United States, but under-recognition and diagnostic uncertainty have limited clinical research to smaller case control studies. In this review we will discuss the contribution of experimental models to the understanding of TRALI pathophysiology and potential therapeutic approache...

  20. On the model-free control of an experimental greenhouse

    OpenAIRE

    Lafont, Frédéric; Pessel, Nathalie; Balmat, Jean-François; Fliess, Michel

    2013-01-01

    International audience; In spite of a large technical literature, an efficient climate control of a greenhouse remains a very difficult task. Indeed, this process is a complex nonlinear system with strong meteorological disturbances. The newly introduced ''model-free control'' setting is employed here. It is easy to implement, and has already shown excellent performances in many other concrete domains. Successful experimental tests are presented and discussed. They are compared to a Boolean a...