• 제목/요약/키워드: Effective

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Evaluation of the Excess Free Energy for Two-Center-Lennard-Jones Liquids Using the Vent Effective Acceptance Ratio

  • 홍성도
    • Bulletin of the Korean Chemical Society
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    • 제21권7호
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    • pp.697-700
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    • 2000
  • A method of calculating the excess Helmholtz free energy from the average of the bent effective acceptance ratio for two-center-Lennard-Jones liquids has been presented. The bent effective acceptance ratio has been newly composed from the acceptan ce ratio for the potential energy difference between a configuration in the Metropolis Monte Carlo procedure and random virtual configuration generated by the separate parallel Monte Carlo procedure and the Boltzmann factor for half the potential energy difference. The excess Helmholtz free energy was calculated directly from the average of the bent effective acceptance ratio through a single Metropolis Monte Carlo run. Because the separate parallel Monte Carlo procedure was used, this method can be applied to molecular dynamics simulations. For two-center-Lennard-Jones liquids, the average of the bent effective acceptance ratio gave better results than use of the modified effective acceptance ratio in the previous work.

실리카겔 충전층에서의 유효열전도율 측정 (Measurement of Effective Thermal Conductivity in Silica Gel Packed Bed)

  • 권오경;윤재호;김종하
    • 설비공학논문집
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    • 제16권12호
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    • pp.1126-1133
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    • 2004
  • This paper presents an experimental measurement of effective thermal conductivity in an adsorbent packed bed with silica gel A type. The effective thermal conductivity was measured under different conditions of the adsorbent bed temperature, pressure, particle size and water content by using the transient hot wire method. The measured effective thermal conductivity showed to become bigger with decreasing particle size or increasing water content, but it was a little affected with increasing bed temperature and pressure. The bed temperature was varied in the range of 1$0^{\circ}C$ (equation omitted) T (equation omitted) 5$0^{\circ}C$ and the pressure in the range of 10 kPa (equation omitted) P (equation omitted) 190 kPa. The results show that 0.10~0.18 W/mㆍK of effective thermal conductivity measured for the zero water content.

Energy-based evaluation of liquefaction potential of uniform sands

  • Sonmezer, Yetis Bulent
    • Geomechanics and Engineering
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    • 제17권2호
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    • pp.145-156
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    • 2019
  • Since behaviors of loose, dense, silty sands vary under seismic loading, understanding the liquefaction mechanism of sandy soils continues to be an important challenges of geotechnical earthquake engineering. In this study, 36 deformation controlled cyclic simple shear tests were performed and the liquefaction potential of the sands was investigated using three different relative densities (40, 55, 70%), four different effective stresses (25, 50, 100, 150 kPa) and three different shear strain amplitudes (2, 3.5, 5%) by using energy based approach. Experiments revealed the relationship between per unit volume dissipated energy with effective stress, relative density and shear strain. The dissipate energy per unit volume was much less affected by shear strain than effective stress and relative density. In other words, the dissipated energy is strongly dependent on relative density and effective stress. These results show that the dissipated energy per unit volume is very useful and may contain the non-uniform loading conditions of the earthquake spectrum. When multiple regression analysis is performed on experiment results, a relationship is proposed that gives liquefaction energy of sandy soils depending on relative density and effective stress parameters.

청폐사간탕(淸肺瀉肝湯)과 단미(單味)들이 Hypoxia-Reoxygenation에 의해 손상받은 Mouse Neuroblastoma 2a Cells에 미치는 영향(影響) (The effects of Chungpesagan-Tang and herbs on Mouse neuroblastoma 2a cells damaged by hypoxia-reoxygenation)

  • 문하경;김종우;강철훈;황의완
    • 동의신경정신과학회지
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    • 제16권2호
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    • pp.89-112
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    • 2005
  • Object : This study was designed to assess effect of Chungpesagan-Tang and herbs on Mouse neuroblastoma 2a cells damaged by hypoxia-reoxygenation. Method : Mouse neuroblastoma 2a (N2a) cells were measured by MTT assay and LDH assay after 48h hypoxia and 6h reoxygenation. Mouse neuroblastoma 2a (N2a) cells were treated by Chungpesagan-Tang and herbs. Result : In MTT assay of hypoxia all of herbs were almost ineffective and Hubak was a little effective. 2. In MTT assay of reoxygenation most of herbs were not effective. But Hubak was some effective. 3. In LDH assay of hypoxia all of herbs were effective. Especially Chungpesagan-Tang were equally effective on all of concentration. 4. In LDH assay of reoxygenation all of herbs were generally effective. Especially Chungpesagan-Tang and Baekji were highly effective and Kilkyung was also effective on low concentration. 5, The herbs were generally effective on LDH assay of hypoxia and reoxygenation. Conclusion : The results suggest that Chungpesagan-Tang and all of herbs may have protective effect on condition of oxidative stress and can be applied on the development of a new medicine for neurodegenerative disease like dementia.

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Performance Analysis of a Combination of Carry-in and Remarshalling Algorithms

  • PARK, Young-Kyu;UM, Kyung-Ho
    • 산경연구논집
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    • 제11권10호
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    • pp.75-89
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    • 2020
  • Purpose: The container terminal is an area that plays an important role in the country's import and export. As the volume of containers increased worldwide, competition between terminals became fiercer, and increasing the productivity of terminals became more important. Re-handling is a serious obstacle that lowers the productivity of terminal. There are two ways to reduce re-handling in the terminal yard. The first method is to load containers in terminal yards using effective carry-in algorithms that reduce re-handling. The second method is to carry out effective remarshalling. In this paper, the performance of various carry-in algorithms and various remarshalling algorithms are reviewed. Next, we try to find the most effective combination of carry-in algorithm and remarshalling algorithm. Research design, data and methodology: In this paper, we analyze the performance of the four carry-in algorithms, AP, MDF, LVF, RP and the four remarshalling algorithms, ASI, ASI+, ASO, ASO+. And after making all the combinations of carry-in algorithms and remarshalling algorithms, we compare their performance to find the best combination. To that end, many experiments are conducted with eight types of 100 bays through simulation. Results: The results of experiments showed that AP was effective among the carry-in algorithms and ASO+ was effective among remarshalling algorithms. In the case of the LVF algorithm, the effect of carrying in was bad, but it was found to be effective in finding remarshalling solution. And we could see that ASI+ and ASO+, algorithms that carry out remarshalling even if they fail to find remarshalling solution, are also more effective than ASI and ASO. And among the combinations of carry-in algorithms and remarshalling algorithms, we could see that the combination of AP algorithm and ASO+ algorithm was the most effective combination. Conclusion: We compared the performance of the carry-in algorithms and the remarshalling algorithms and the performance of their combination. Since the performance of the container yard has a significant effect on the performance of the entire container terminal, it is believed that the results of this experiment will be effective in improving the performance of the container terminal when carrying-in or when remarshalling.

청심온담탕(淸心溫膽湯)이 백서(白鼠)의 항경련(抗經攣), 해열(解熱), 진통(鎭痛), 진정(鎭靜) 및 GABAergic system에 미치는 영향(影響) (The effect of Anticonvulsion, Antipyretic, Analgesic, Sedative and GABAergic system on mice by ChongsimOndamTang)

  • 김재형;이상용
    • 동의신경정신과학회지
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    • 제8권1호
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    • pp.95-109
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    • 1997
  • In order to prove the experimental effectiveness of ChongsimOndamTang by categotizing COTⅠ, COTIⅡ, COTⅢ and COTⅣ according to the volume of COT extract,the anticonvulsion action, the antipyretic action, the analgesic action,the sedative action, and the activity of GABA transaminase, the actuvity concentration of GABA,the activity of GAD in GABAergic system comparing data with control group and observation data show the results as follows.1. The anticonvulsion effect on the convulsion induced by strychine it was significantly effective in COTⅣ and the time to death after the occurrence of the convulsion it was significantly effective in COTⅢ and COTⅣ, and the time to death after the occurrence the convulsion induced by the electrical shock of ECT unit it was significantly effective in all sample groups.2. The hypothemic effect was significantly effective in COT Ⅲ after 1 hour and 2 hour and was significantly effective COTⅣafter 1 hour and 4 hour, and the antipyretic effect on the febrile induced by endotoxin it was significantly effective in COTⅢ every 3 hour and was significantly effective in COTⅣ after 3 hour and 4 hour.3. The analgesic effect was significantly effective in COTⅢ and COTⅣ by decreasing the number of writhing syndrome.4. The sedative effect was decreased significantly all in COTⅢ and COTⅣ after 60 min, 90 min and 120 min.5. The activity of GABA transaminase was decreased significantly in COTⅡ and COTⅢ. 6. The activity concrntration of GABA was increased signifivantly in COTⅡ and COTⅢ. 7. The activity of GAD was increased significantly in COTⅡ and COTⅢ. The results show that ChongsimOndamTang can be an effective cure in mice on the anticonvulsion,the antipyretic , the analgesic,the sedative and the control of the GABAergic system in brain, and it can be used of the epilepsy and convulsive diseases clinically.

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전자선 에너지 및 조사야에 따른 유효선원 피부 간 거리 변화 (Variation of Effective SSD According to Electron Energies and Irradiated Field Sizes)

  • 양칠용;염하용;정태식
    • Radiation Oncology Journal
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    • 제5권2호
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    • pp.157-163
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    • 1987
  • It is known that fixed source to skin distance (SSD) cannot be used when the treatment field is sloped or larger than the size of second collimator in electron beam irradiation and inverse square law using effective ssd should be adopted. Effective SSDs were measured in different field sizes in each 6, 9, 12, 15 and 18MeV electron energy by suing NELAC 1018D linear accelerator of Kosin Medical Center. We found important parmeters of effective SSD. 1. Minimum effective SSD was 58.8cm in small field size of $6\pm6cm$ and maximum effective SSD was 94.9cm in large field size of $25\pm25cm$, with 6MeV energy. It's difference was 36.1cm. The dose rate at measuring point was quite different even with a small difference of SSD in small field $(6\times6cm)$ and low energy (6 MeV). 2. Effective SSD increased with field size in same electron energy. 3. Effective SSDs gradually increased with the electron energies and reached maximum at 12 or 15 MeV electron energy and decreased again at 18MeV electron energy in each identical field size. And so the effective SSD should be measured in each energy and field size for practical radiotherapy.

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생체역동학 모델을 이용한 감마선 방출 핵종의 유효반감기 계산 (Calculation of Effective Half-life of Gamma Emission Radionuclide using Bio-kinetic Model)

  • 이상경;정규환;이지연;김봉기;김정민
    • 방사선산업학회지
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    • 제12권4호
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    • pp.277-285
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    • 2018
  • Patients administered radioisotope for medical purposes are regulated by each country to quarantine them until their body's radioactivity contents decrease below release criteria. To predict the quarantine period and provide it to medical staffs and patients, it is necessary to approach the assessment of the exposure dose of persons due to patients in a realistic manner. For this purpose, a whole-body effective half-life should be applied to the dose assessment equation instead of the physical half-life. In this study, we constructed a bio-kinetic model for each nuclear species based on the ICRP publication to obtain a whole-body effective half-life of 10 unsealed gamma-ray emitting nuclei from the notification of Nuclear Safety and Security Commission, and calculated the effective half-life mathematically by simulating the distribution of the radioisotope administered in the whole body as well as each organ scale. The whole-body effective half-life of $^{198}Au$, $^{67}Ga$, $^{123}I$, $^{111}In$, $^{186}Re$, $^{99m}Tc$, and $^{201}TI$ were 1,93, 2.57, 0.295, 2.805, 1.561, 0.245, and 2.397 days respectively. However, it was found to be undesirable to offer a single value of the effective half-life of $^{125}I$, $^{131}I$, and $^{169}Yb$ because the changes in the effective half-life show no linearity. A bio-kinetic model created for the internal exposure assessment has been shown to be possible to calculate the effective half-life of radioisotopes administered in the patient's body, but subsequent studies of radiolabeled compounds are required as well.

균열성장 지연현상에 대한 유효 소성역 개념을 사용한 파괴역학적 연구 (A Fracture Mechanic's Study for Crack Growth Retardation Phenomenon using Effective Plastic Zone Concept)

  • 강용구;이태원;박창용
    • 한국기계가공학회지
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    • 제14권2호
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    • pp.112-120
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    • 2015
  • In this study, the growth rate of surface cracks (da/dN) during the retardation period was analyzed in terms of effective stress intensity factor range(${\Delta}K_{eff}^*$) obtained by using the proposed effective plastic zone concept. Effective stress intensity factors obtained by using the effective plastic zone concept were smaller than those obtained by using Willenborg analysis. On the growth rate of surface cracks analyzed by ${\Delta}K$, the dependence of overload stress levels appears. On the growth rate by ${\Delta}K_{eff}$ obtained by Willenborg analysis, there is a linear relationship with two different slops between da/dN and ${\Delta}K_{eff}$. However, on the growth rate by ${\Delta}K_{eff}^*$ obtained by the proposed effective plastic zone concept, there is a linear relationship between da/dN and ${\Delta}K_{eff}^*$ that coincides with the results of constant amplitude loading.

건뇌양(健腦揚)과 단미(單味)들이 Hypoxia-Reoxygenation에 의해 손상받은 Mouse Neuroblastoma 2a Cells에 미치는 영향(影響) (The Effects Kunnuetang and Herbs on Mouse Neuroblastoma 2a Cells Damaged by Hypoxia-reoxygenation)

  • 염창섭;김종우;강철훈;황의완
    • 동의신경정신과학회지
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    • 제16권2호
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    • pp.73-88
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    • 2005
  • Object : This study was designed to asses the effect of Kunnuetang and herbs on Mouse neuroblastoma 2a cells damaged by hypoxia-reoxygenation. Method : Mouse neuroblastoma 2a (N2a) cells were measured by MTT assay and LDH assay after 48h hypoxia and 6h reoxygenation. Mouse neuroblastoma 2a (N2a) cells were treated by Kunnuetang, Duchang and Daejo. Result : 1. Kunnuetang, was effective on LDH assay of hypoxia and reoxygenation. 2. Duchang and Daejo were generally effective on LDH assay of hypoxia and reoxygenation. 3. In MTT assay of hypoxia Kunnuetang was not effective. Duchung and Daejo were not generally effective on MTT assay, but in certain condition Herbs were effective. 4. In MTT assay of reoxygenation Kunnuetang and Daejo were not effective. But Duchung was effective in certain condition. Conclusion : The results suggest that Kunnuetang, Duchang and Daejo may have protective effect on vascular dementia and ad patient.

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