• Title/Summary/Keyword: Model Experimental Research

Search Result 4,750, Processing Time 0.031 seconds

Neutron Cross Section Evaluation on Mo-95, Tc-99, Ru-101 and Rh-1()3 in the Fast Energy Region

  • Lee, Y. D.;J. H. Chang
    • Nuclear Engineering and Technology
    • /
    • v.34 no.6
    • /
    • pp.533-544
    • /
    • 2002
  • The neutron induced nuclear data for Mo-95, Tc-99, Ru-101 and Rh-103 was calculated and evaluated in the fast energy region. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated from the parameters. Spherical optical model, statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were used in the calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files The model- calculated total and capture cross sections were in good agreement with the reference experimental data. The direct capture contribution improved the capture cross sections in pre- equilibrium region. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

Evaluation of Neutron Cross Sections for Eu-153, Gd-155 and Gd-157

  • Lee, Y. D.;J. H. Chang
    • Nuclear Engineering and Technology
    • /
    • v.35 no.1
    • /
    • pp.35-44
    • /
    • 2003
  • The neutron induced nuclear data for Eu-153, Gd-155 and Cd-157 are calculated and evaluated in the high energy region. The evaluation procedure for deformed nuclei is setup by using Ecis-Empire codes. The energy dependent optical model potential parameters are searched based on the recent experimental data and applied up to 20 MeV. Optical model, full featured Hauser-Feshbach model and multistep direct and multistep compound model are used in the calculation. The direct-semidirect capture model and the direct coupled-channels contribution to discrete levels are introduced to improve the capture and inelastic scattering cross sections. The theoretically calculated cross sections are compared with the experimental data and the evaluated files. The model-calculated total and capture cross sections are in good agreement with the reference experimental data. The evaluated cross section results are compiled to ENDF-6 format and are expected to improve the ENDF/B-Vl.

NEUTRON CROSS SECTION DATA LIBRARY FOR PD-105, AG-109, XE-131 AND CS-133

  • LEE Y. D.;CHANG J. H.
    • Nuclear Engineering and Technology
    • /
    • v.37 no.1
    • /
    • pp.101-108
    • /
    • 2005
  • The neutron induced nuclear cross-section data for Pd-105, Ag-109, Xe-131, and Cs-133 were calculated and evaluated from an unresolved energy to 20 MeV. The energy dependent optical model potential parameters were extracted based on recent experimental data and applied up to 20 MeV. A spherical optical model and a statistical model for the equilibrium energy, and a multistep direct and a multistep compound model for the pre-equilibrium energy were used in the calculation. The direct capture model was recently introduced for fast neutron capture. The theoretically calculated cross-sections were compared with the experimental data and the evaluated files. The total and capture cross-sections calculated using the model were in good agreement with the reference experimental data. The evaluated cross-section results were compiled in ENDF-6 format and merged with the resonance component, already adopted in the ENDF/B-VI release 8. New data library files covering from thermal to 20 MeV were created. They are at the preliminary stage of an ENDF/B- VII release.

Neutron Cross Section Evaluation on Pr-141, Nd-143, Nd-145, Sm-147 and Sm-149

  • Lee, Y. D.;J. H. Chang
    • Nuclear Engineering and Technology
    • /
    • v.34 no.4
    • /
    • pp.370-381
    • /
    • 2002
  • The neutron induced nuclear data for Pr-141, Nd-143, Nd-145, Sm-147 and Sm-149 were calculated and evaluated from 10 keV to 20 MeV. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated. Spherical optical model , statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were introduced in Empire calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files. The model calculated total and capture cross sections were in good agreement with the reference experimental data. The capture cross sections in pre-equilibrium were enhanced in recent released Empire version. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

Education based on the health belief model to improve the level of physical activity

  • Khodaveisi, Masoud;Azizpour, Bahman;Jadidi, Ali;Mohammadi, Younes
    • Korean Journal of Exercise Nutrition
    • /
    • v.25 no.4
    • /
    • pp.17-23
    • /
    • 2021
  • [Purpose] This study aimed to investigate the effect of education based on the health belief model on the physical activity of the staff of the University of Medical Sciences. [Methods] This semi-experimental study was conducted on 130 university staff aged 25-50 years from the Hamadan University of Medical Sciences. Inclusion criteria were having at least 1 year of work experience, lack of acute and chronic physical and mental illnesses, and not using drugs that affect physical activity. The samples were randomly divided into two groups. The experimental group received three training sessions based on the health belief model. Before and 2 months after training, the control and experimental groups were evaluated via the following questionnaires: (1) demographic information questionnaire, (2) Health Belief Model Questionnaire, and (3) International Physical Activity Questionnaire. Finally, data were analyzed statistically. [Results] The training process resulted in a significant increase in the mean scores of the health belief model constructs in the experimental group, but changes in the control group were not significant. Self-efficacy was the strongest predictor of physical activity. [Conclusion] The health belief model is a useful model for improving individuals' understanding of the benefits of physical activity.

Centrifuge Model Experiments on Behaviors of Single Pile (단말뚝 거동에 관한 원심모형실험)

  • Yoo, Nam-Jae;Lee, Myeung-Woog;Lee, Jong-Ho
    • Journal of Industrial Technology
    • /
    • v.17
    • /
    • pp.111-118
    • /
    • 1997
  • This thesis is an experimental research of investigating behavior of single pile, subjected to the vertical compression loads, using the centrifuge facility located in the geotechnical engineering laboratory in Kangwon National University. Centrifugal model experiments of model pile were carried out changing diameter of model pile, relative density of sandy ground and the gravitational level applied in the centrifuge. Thus, their effects on the load-settlement behavior and the ultimate bearing capacity of pile were investigated. Experimental results obtained from centrifuge model tests were compared with the theoretical or semi-empirical equations to analyze values of ultimate bearing capacity of model pile. When we compare the ultimate bearing capacity of experimental results with the ultimate bearing capacity of theorical results, the experimental results appear more higher in the De Beer method and Meyerhof. Expecially, Terzaghi method is very same as the experimental results normally.

  • PDF

Experimental Study of Wave Run-up on Semi-submersible Offshore Structures in Regular Waves (규칙파 중 반잠수식 해양구조물 주위의 런업에 관한 실험 연구)

  • Kim, Namwoo;Nam, Bo Woo;Cho, Yoonsang;Sung, Hong Gun;Hong, Sa Young
    • Journal of Ocean Engineering and Technology
    • /
    • v.28 no.1
    • /
    • pp.6-11
    • /
    • 2014
  • This paper presents the results of an experimental study of wave run-ups on a semi-submersible offshore structure. A series of model tests with a 1:80 scale ratio were carried out in the two-dimensional wave basin of MOERI/KIOST. The experimental model had two columns and one pontoon. The model was fixed and wave elevations were measured at five points per column. Two different draft (operational & survival) conditions and three wave heights were considered under regular wave conditions. First, the nonlinear characteristics of wave run-ups are discussed by using the time series data. Then, the wave heights are compared with numerical results based on the potential flow model. The comparison shows fairly good correlation between the experiments and computations. Finally, wave run-ups under the operational and survival conditions are suggested.

Development of Stem Profile and Taper Equation for Carpinus laxiflora in Jeju Experimental Forests of Korea Forest Research Institute (국립산림과학원 제주시험림의 서어나무 수간형태와 수간곡선식 추정)

  • Chung, Young-Gyo;Kim, Dae-Hyun;Kim, Cheol-Min
    • Journal of agriculture & life science
    • /
    • v.44 no.4
    • /
    • pp.1-7
    • /
    • 2010
  • Data was collected to develop equation for predicting stemp taper for Carpinus laxiflora in Jeju Experimental Forests. The Models tested for choosing the best-fit equations were Max & Burkhart's model, Kozak's model, and Lee's model. Performance of the equations in predicting stem diameter at a specific point along a stem was evaluated with fit and validation statistics and distribution of residuals on predicted values. In result, all the three models gave slightly better values of fitting statistics. In plotting residuals against predicted diameter, Max & Burkhart's model showed underestimation in predicting small diameter and Lee's Model did the same in predicting small diameter. Based on the above analysis of the three models in predicting stem taper, Kozak's model was chosen for the best-fit stem taper equations, and its parameters were given for C. laxiflora. Kozak's model was used to develop a stem volume table of outside bark for C. laxiflora.

Experimental and numerical studies of mono-strand anchorage

  • Marceau, D.;Bastien, J.;Fafard, M.;Chabert, A.
    • Structural Engineering and Mechanics
    • /
    • v.12 no.2
    • /
    • pp.119-134
    • /
    • 2001
  • This paper deals with an experimental and numerical study of a mono-strand wedge anchor head mechanism. First, the experimental program is presented and monitored data such as wedge slippage, anchor deflection and strain distributions along external peripheral surfaces of the anchor head are presented and discussed. In accordance with the experimental set up, these data concern only the global behaviour of the mechanism and cannot provide valuable information such as internal stress-strains distributions, stress concentrations and percentage of yielded volume. Therefore, the second part of this paper deals with the development of an efficient numerical finite element model capable of providing mechanism of the core information. The numerical model which includes all kinematics/material/contact non-linearities is first calibrated using experimental data. Subsequently, a numerical study of the anchorage mechanism is performed and its behaviour is compared to the behaviour of a slightly geometrically modified mechanism where the external diameter has been increased by 5 mm. Finally, different topics influencing the anchorage mechanism behaviour are addressed such as lubrication and wedge shape.

Flexural and tensile properties of a glass fiber-reinforced ultra-high-strength concrete: an experimental, micromechanical and numerical study

  • Roth, M. Jason;Slawson, Thomas R.;Flores, Omar G.
    • Computers and Concrete
    • /
    • v.7 no.2
    • /
    • pp.169-190
    • /
    • 2010
  • The focus of this research effort was characterization of the flexural and tensile properties of a specific ultra-high-strength, fiber-reinforced concrete material. The material exhibited a mean unconfined compressive strength of approximately 140 MPa and was reinforced with short, randomly distributed alkali resistant glass fibers. As a part of the study, coupled experimental, analytical and numerical investigations were performed. Flexural and direct tension tests were first conducted to experimentally characterize material behavior. Following experimentation, a micromechanically-based analytical model was utilized to calculate the material's tensile failure response, which was compared to the experimental results. Lastly, to investigate the relationship between the tensile failure and flexural response, a numerical analysis of the flexural experiments was performed utilizing the experimentally developed tensile failure function. Results of the experimental, analytical and numerical investigations are presented herein.