• Title/Summary/Keyword: Experimental Simulation

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Effect of Radioisotope Position on Performance of Industrial SPECT (방사성동위원소 위치에 따른 산업용 SPECT 성능에 미치는 영향)

  • Moon, Jinho;Kim, Jongbum;Jung, Sung-Hee
    • Journal of Radiation Industry
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    • v.6 no.3
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    • pp.245-249
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    • 2012
  • Demand of fluid flow visualization has increased in industrial processes, because medical imaging technology is highly developed. As a part of the industrial process imaging technology, industrial single photon emission computed tomography (SPECT) system was developed to measure the cross-sectional distribution of the process fluid. The SPECT consists of 36 NaI (Tl) detectors with the hexagonal configuration. Reconstructed images were acquired for various positions of radioactive source to estimate SPECT device performance. To evaluate the reliability of the experimental results, the Monte Carlo simulation results are compared with experimental results. In general, the experimental and simulation results were consistent. However, as the source position was getting far from the center of the reactor, the accuracy of reconstructed images was compromised. It seems to be due to the inconsistent spatial resolution of the collimators according to the source position.

Comparison of Experimental and Simulation Results for Flow Characteristics around Jet Impingement/Effusion Hole in Concave Hemispherical Surface (오목한 반구면의 Jet Impingement/Effusion Hole 주변 유동 특성에 대한 실험과 시뮬레이션의 비교)

  • Youn, Sungji;Seo, Heerim;Yeom, Eunseop
    • Journal of the Korean Society of Visualization
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    • v.20 no.2
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    • pp.28-37
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    • 2022
  • Flow characteristics of jet impingement over concave hemispherical surface with effusion cooling holes is relatively more complex than that of a flat surface, so the experimental validation for computational fluid dynamics (CFD) results is important. In this study, experimental results were compared with simulation results obtained by assuming different turbulence models. The vortex was observed in the region between the central jets where the recirculation structure appeared. The different patterns of vorticity distributions were observed for each turbulence models due to different interaction of the injected jet flow. Among them, the transition k-kl-ω model predicted similarly not only the jet potential core region with higher velocity, but also the recirculation region between the central jets. From the validation, it may be helpful to accurately predict heat and mass transfer in jet impingement/effusion hole system.

Experiment and simulation analysis on full scale double-layer concrete shell

  • Thanh Quang Khai Lam;Thi My Dung Do
    • Computers and Concrete
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    • v.31 no.1
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    • pp.9-21
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    • 2023
  • The published studies usually used analytical method, numerical methods or experimental method to determine the stress-strain state and displacement of the single-layer or multi-layer curved shell types, but with a small scale model. However, a full scale multi-layer doubly curved concrete shell roof model should be researched. This paper presents the results of the experiment and simulation analysis involving stress-strain state, sliding between layers, the formation and development of the full scale double-layer doubly curved concrete shell roof when this shell begins to crack. The results of the this study have constructed the load-sliding strain relationship; strain diagram; stress diagram in the shell layers; the Nx, Ny membrane force diagram and deflection of shell. Thisresults by experimental method on a full scale model of concrete have clarified the working of multi-layer doubly curved concrete shell roof. The experimental and simulation results are compared with each other and compared with the Sap2000 software.

A Study into the Effect of the CT Simulation Program on Clinical Education (전산화단층촬영 시뮬레이션 프로그램의 임상교육 효과에 관한 연구)

  • Kim, Yong-Wan;Kim, Jung-Sam;Lee, Kyung-Rok
    • Journal of radiological science and technology
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    • v.32 no.4
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    • pp.445-451
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    • 2009
  • The computed tomography(CT) simulation tool provides virtual experimental environment without using a high cost medical equipment. We made teaching materials for the CT simulation tools and educated the students and entry level of radio-technologists. We divided the experimental objects into two groups; students who took only theoretical classes (group 1) and students who took both theoretical and simulation classes (group 2). The results showed that the group 2 outperformed group 1 significantly, which indicates that the simulation program provides a good educational material for not only students but also radio-technologists.

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Simulation of the Forming Process of the Shielded Slot Plate for the Molten Carbonate Fuel Cell Using a Ductile Fracture Criterion (연성파괴조건을 사용한 용융탄산염 연료전지용 쉴디드 슬롯 플레이트의 성형 공정 유한요소 해석)

  • Lee, C.W.;Yang, D.Y.;Lee, S.R.;Kang, D.W.;Chang, I.G.;Lee, T.W.
    • Transactions of Materials Processing
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    • v.21 no.5
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    • pp.298-304
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    • 2012
  • The shielded slot plates for a molten carbonate fuel cell(MCFC) have a sheared corrugated trapezoidal pattern. In the FEM simulations for the production of the shielded slot plate, the user material subroutine VUMAT in the commercial FEM software ABAQUS was used to implement a ductile fracture criterion. The critical damage value for the ductile fracture criterion was determined by comparing the experimental results of the shearing process with the simulation results. Using the ductile fracture criterion, the FEM simulation of the three-dimensional forming process of the shielded slot plate was conducted. The effects of the shearing process on the forming process were examined through FEM simulation and experiments. The forming simulation of nine unit cells was conducted. Using the simulation results of the forming process, the deformed shape after springback was calculated. The experimental result shows good agreement with the simulation.

The Effects of Simulation-based Infection Control Training on the Intensive Care Unit Nurses' Perception, Clinical Performance, and Self-Efficacy of Infection Control (시뮬레이션기반 감염관리교육이 중환자실 간호사의 감염 관리에 대한 인식도, 임상 수행도, 자기효능감에 미치는 영향)

  • Cho, Sung Sook;Kim, Kyung Mi;Lee, Beoung Yeo;Park, Sun A
    • Journal of Korean Clinical Nursing Research
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    • v.18 no.3
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    • pp.381-390
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    • 2012
  • Purpose: This study was conducted to examine the effects of simulation-based infection control training on the ICU nurses' perception, clinical performance, and self-efficacy of infection control. Methods: Thirty-eight nurses were assigned into two groups using a career stratified randomization. In the experimental group, the subjects received a simulation-based infection control training, whereas the control group participated in a conventional lecture-based training. Two weeks after the completion of the training sessions, the participants were evaluated for perception, clinical performance, and self-efficacy regarding the infection control. Results: The experimental group that received simulation-based infection control training showed an improvement in perceiving the infection control compared to that of the control group, but the difference was not statistically significant. In terms of the clinical performance, the experimental group and the control group scored $26.05{\pm}3.22$ and $18.53{\pm}3.37$ points respectively, demonstrating a statistical significance (p<.001). There was no significant difference between the two groups in regards to the self-efficacy. Conclusion: The developed simulation-based infection control training showed positive effects in improving clinical performance of infection control over conventional lecture-based training, confirming that a simulation-based training is an effective method in advancing the practical performance of ICU nurses.

Effects of a Simulation-based Educational Program for Gastroendoscopic Surgery Patients (위내시경 수술을 받는 조기 위암 대상자를 위한 동영상 시뮬레이션 교육 프로그램의 효과)

  • Kwon, Su Young;Lee, Jia
    • Korean Journal of Adult Nursing
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    • v.25 no.5
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    • pp.494-503
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    • 2013
  • Purpose: The purpose of this study was to examine the effects of a simulation-based educational program on anxiety and discomfort in patients with early stage of stomach cancer or stomach adenoma undergoing gastroendoscopic surgery. Methods: The study employed a non-equivalence control group and non-synchronized design to prevent diffusion of treatment. Data were collected from 110 patients (experimental group=55, control group=55) admitted to a department of gastroenterology to undergo gastroendoscopic surgery for early stage of stomach cancer or stomach adenoma. The program was conducted as a 30-minute simulation-based education including 12 processes which patients would experience. Outcome variables were state anxiety, objective discomfort, and subjective discomfort. Results: The scores of state anxiety in the experimental group significantly decreased over time compared to those in the control group. The scores of objective and subjective discomfort after surgery in the experimental group were significantly lower than those in the control group. Conclusion: The study findings suggested that the simulation-based educational program making a person feel sense of real experiences could reduce anxiety and discomfort in gastroendoscopic surgery patients.

Target Scattering Echo Simulation for Active Sonar System in the Geometric Optics Region (기하광학영역에서의 능동소나 표적신호합성)

  • 신기철;박재은;김재수;최상문;김우식
    • The Journal of the Acoustical Society of Korea
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    • v.20 no.3
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    • pp.91-97
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    • 2001
  • Since the new field information of target signal is important in the development and verification of active sonar system, experimental method and simulation technique are widely used in order to analyze the detail characteristics of target scattered echoes. Therefore, in this paper, the scale target experiment is performed to develope and Improve the target signal simulation model. Since the experimental results show that the specular reflection is the major component among scattering mechanisms, the target signal simulation model based on the Geometric Optics Theory (GOT) is developed. Complex target is separated into simple shapes, known as canonical shape. The contribution from individual canonical shapes are summed with proper phase and amplitude to produce the target strength of the whole complex body. Simulated target signal is compared with the experimental results and discussed.

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Simulation of Pool Fire with Two Rooms Using FDS Model (화재분석모델을 이용한 이중격실화재 검증분석)

  • Kim, Bong-Hyun;Bae, Yong-Bum;Ryu, Su-Hyun;Lee, Gong-Hee;Kim, Yun-Il;Moon, Chan-Ki;Park, Jong-Seok
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.1332-1337
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    • 2008
  • Fire model shall be verified and validated to reliably predict the consequences of fires within its limitations. This study aims to predict pool fire with two rooms using FDS and to coompare FDS simulation results with PRISME experimental data which can be applicable to the fire of nuclear power plant facility. Four different sizes of grid (0.08m, 0.1m, 0.125m, 0.2m) are used in the simulation and the simulated results of specific quantities such as temperature, chemical composition, heat flux and heat release rate are compared to the experimental data. From this study, the FDS simulation results with the finer grid resolution show better similarity and trend with pool fire experimental data. The sensitivity analysis and the selection of the proper size grid are essential to predict the consequences of pool fire with two rooms reliably.

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Experimental and Computational Study on the Mold Shrinkage of PPS Resin in Injection Molded Specimen

  • Pak, Hyosang;Sim, Hyojin;Oh, Hyeon-Kyung;Lee, Guen-Ho;Kang, Min-A;Lyu, Min-Young
    • Elastomers and Composites
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    • v.55 no.2
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    • pp.120-127
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    • 2020
  • In this study, molding shrinkage of PPS resin was investigated. Two types of PPS resins with differing glass fiber and calcium carbonate content were used for this purpose. To observe mold shrinkage, molding conditions based on injection temperature, injection speed, and the position of the cushion were selected. Circular and rectangular specimens were used for the study model. Injection molding simulation was performed to predict the filling pattern and mold shrinkage, and the simulation results were compared with the experimental conclusions. It was observed that the mold shrinkage showed the highest shrinkage (distributed from 0.05% to 0.32%) dependence on the injection temperature, and the lowest shrinkage (distributed from 0.05% to 0.31%) dependence on the injection speed. The role of the position of the cushion in mold shrinkage was difficult to observe. The results of the simulation mostly agreed with the experimental results; however, for some molding conditions, the mold shrinkage in the simulation was overestimated as compared to that in the experiment.