• Title/Summary/Keyword: Framework structure

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An FSI Simulation of the Metal Panel Deflection in a Shock Tube Using Illinois Rocstar Simulation Suite (일리노이 록스타 해석환경을 활용한 충격파관 내 금속패널 변형의 유체·구조 연성 해석)

  • Shin, Jung Hun;Sa, Jeong Hwan;Kim, Han Gi;Cho, Keum Won
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.5
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    • pp.361-366
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    • 2017
  • As the recent development of computing architecture and application software technology, real world simulation, which is the ultimate destination of computer simulation, is emerging as a practical issue in several research sectors. In this paper, metal plate motion in a square shock tube for small time interval was calculated using a supercomputing-based fluid-structure-combustion multi-physics simulation tool called Illinois Rocstar, developed in a US national R amp; D program at the University of Illinois. Afterwards, the simulation results were compared with those from experiments. The coupled solvers for unsteady compressible fluid dynamics and for structural analysis were based on the finite volume structured grid system and the large deformation linear elastic model, respectively. In addition, a strong correlation between calculation and experiment was shown, probably because of the predictor-corrector time-integration scheme framework. In the future, additional validation studies and code improvements for higher accuracy will be conducted to obtain a reliable open-source software research tool.

Fast Bayesian Inversion of Geophysical Data (지구물리 자료의 고속 베이지안 역산)

  • Oh, Seok-Hoon;Kwon, Byung-Doo;Nam, Jae-Cheol;Kee, Duk-Kee
    • Journal of the Korean Geophysical Society
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    • v.3 no.3
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    • pp.161-174
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    • 2000
  • Bayesian inversion is a stable approach to infer the subsurface structure with the limited data from geophysical explorations. In geophysical inverse process, due to the finite and discrete characteristics of field data and modeling process, some uncertainties are inherent and therefore probabilistic approach to the geophysical inversion is required. Bayesian framework provides theoretical base for the confidency and uncertainty analysis for the inference. However, most of the Bayesian inversion require the integration process of high dimension, so massive calculations like a Monte Carlo integration is demanded to solve it. This method, though, seemed suitable to apply to the geophysical problems which have the characteristics of highly non-linearity, we are faced to meet the promptness and convenience in field process. In this study, by the Gaussian approximation for the observed data and a priori information, fast Bayesian inversion scheme is developed and applied to the model problem with electric well logging and dipole-dipole resistivity data. Each covariance matrices are induced by geostatistical method and optimization technique resulted in maximum a posteriori information. Especially a priori information is evaluated by the cross-validation technique. And the uncertainty analysis was performed to interpret the resistivity structure by simulation of a posteriori covariance matrix.

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Analysis of Verbal Interaction within a Homogeneous Group in Inquiry Activity of the 'Use of Lenses' Unit in Elementary School (초등학교 '렌즈의 이용' 단원 탐구활동에서 나타나는 동질 모둠별 언어적 상호작용의 특징 분석)

  • Chung, Hee-Jung;Kwon, Gyeong-Pil
    • Korean Journal of Optics and Photonics
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    • v.28 no.6
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    • pp.327-333
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    • 2017
  • The purpose of this research was to analyze characteristics of verbal interactions of each homogeneous group in the learning of the 6th grade's 'Use of Lenses' Unit. For this research, six learning sessions were conducted in one 6th grade class composed of a high-academic-achievement group, an intermediate-academic-achievement group, and a low-academic-achievement group. All lessons were recorded, to analyze the verbal interactions of each group, and the transcribed data were analyzed using the verbal-interaction analytic framework. Results included: In the upper group, although opinions were presented more frequently, there were many negative verbal interactions in completing the tasks. The middle group was observed more specifically to accept peer opinions critically in their observational activities. The middle group's members were more active in presenting their opinions than listening to others' opinions. The lower group had difficulties in drawing conclusions because of a lack of ability to persuade peers or to respect the opinions of peers, even though the frequency of verbal interactions was higher than in other groups. Therefore, a homogeneous group structure is good for a simple activity involving a simple inquiry or an exchange of opinions, while a heterogeneous group structure is more effective in activities focused on understanding scientific concepts and knowledge.

Liquefaction-Induced Uplift of Geotechnical Buried Structures: Centrifuge Modeling and Seismic Performance-Based Design (지반 액상화에 의한 지중 매설구조물의 부상: 원심모형시험 및 내진성능설계)

  • Kang, Gi-Chun;Iai, Susumu
    • Journal of the Korean Geotechnical Society
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    • v.28 no.10
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    • pp.5-16
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    • 2012
  • Geotechnical buried structures with relatively light weight have been suffering from uplift damage due to liquefaction in the past earthquakes. The factor of safety approach by Koseki et al. (1997a), which is widely used in seismic design, predicts the triggering of uplift. However, a method for "quantitative" estimates of the uplift displacement has yet to be established. Estimation of the uplift displacement may be an important factor to be considered for designing underground structures under the framework of performance-based design (ISO23469, 2005). Therefore, evaluation of the uplift displacement of buried structure in liquefied ground during earthquakes is needed for a performance-based design as a practical application. In order to predict the uplift displacement quantitatively, a simplified method is derived based on the equilibrium of vertical forces acting on buried structures in backfill during earthquakes (Tobita et al., 2012). The method is verified through comparisons with results of centrifuge model tests and damaged sewerage systems after the 2004 Niigata-ken Chuetsu, Japan, earthquake. The proposed flow diagram for performance-based design includes estimation of the uplift displacement as well as liquefaction limit of backfill.

Financing and Knowledge Accumulation in the Film Industry: Spatial Characteristics of Korean and American Film Industry (영화산업의 자본조달구조와 지식축적과정에 대한 공간적 고찰: 한국과 미국 영화산업의 비교를 통하여)

  • Chung, SunWha
    • Journal of the Economic Geographical Society of Korea
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    • v.20 no.4
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    • pp.453-485
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    • 2017
  • One of the oldest chestnuts in economic geography is this: Cultural and creative industries strongly gather in large cities and this geographic concentration of economic activities leads to regional development. Of course, depending on the circumstances, such a proposition still holds good. But, under the current paradigm shift to knowledge-based economy, it may be open to question. This study aims to investigate financing and knowledge accumulation in the film industry through an alternative framework for explaining their spatial distributions, "formation mechanism of economic space." From the fact that their production organizations are formed on a project basis, project-based financing structure in the investment stage and knowledge accumulation process in the production stage form both axes of it. Film industry as the most mature industry among the cultural and creative industries does not always concentrate in a certain place (industrial agglomeration) or show metropolis-oriented preference. This allows us to reconsider our long brooding theory.

A Study of a Relapse Prevention Program for Alcoholics focused on Action Methods (행위기법을 중심으로 한 알코올의존 재발방지 프로그램 개발에 관한 연구)

  • No, In-Suk;Kim, Seong-Jae
    • Journal of East-West Nursing Research
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    • v.10 no.1
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    • pp.27-40
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    • 2004
  • Relapse is one of the most series problems in alcoholics treatment. Previous studies have shown that significant proportions of treated alcoholics show an early relapse and go through a chronic phase. It is necessity to find more effective relapse prevention program. The Purpose of this study was to develop a relapse prevention program that emphasis on group activities using various action methods. Previous studies revealed that there was no effective therapeutic strategy to prevent relapse and proposed that action methods were more practical ways to be able ti cope with high-risk situation than verbal methods such as discussions and lectures. The special attempt of this program was the application of various actions methods and the integration of many psychosocial therapeutic strategies as compared with many relapse prevention programs. The theoretical framework of this relapse prevention program was based on mainly the Marlatt's Relapse Prevention model and Prochescha and DiClemente's Transtheoretical model. This Program consists of eight structure sessions. Every session has three phase: Warm-up phase, action phase, and sharing phase as sociodrama structure. Sociodrama is based on many of the principles of adult learning. And sociodrama looks at how groups work through an understanding of systems and role theory. Therefore, in working with a group a therapist might explore with them the roles that people play, roles that are missing at present such a visionary and how people can develop new roles or new ways of playing existing roles. The researchers explained the purpose of this study to all participants after their agreement to participate. Voluntary informed consent was obtained from all participants. Every session allows participants to recognize personal specific high-risk situation and to examine possible coping behaviors creatively. Multiple solutions can be proposed, tested and evaluated dramatically, giving new insights or breakthroughs in thinking. This is vital for the initiation of change, and if appropriate, expanding new role development. The first two sessions aim at understanding of relapse process and recognize of high-risk situations focused on orientation about action methods. The next four sessions deal with high-risk situations. The last two sessions give participants opportunities to venture new life-styles. The methods and approaches used in this program utilized as a tool to explore and practice possible coping strategies. and this program can contribute to prevent relapse episode if tune with the particular high-risk situation by using active practices in safe environment.

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A Study on Job Rotation in Civil Service (공무원 순환보직에 관한 연구)

  • Kim, Kwang-ho
    • KDI Journal of Economic Policy
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    • v.30 no.2
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    • pp.61-97
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    • 2008
  • This paper aims at analyzing the practice of job rotation in the Korean government and putting forward policy suggestions. The Korean government is often accused of low capacity and weak competitiveness, which mainly result from the low expertise of public officials. Considering the high quality of human resources flowing into the public sector in Korea, solutions should be found from the structure of the system. This paper regards frequent position changes due to excessive job rotation as a key factor undermining the accumulation of expertise and conducts in-depth analyses. The current practice of frequent rotation shows that the average tenure period of government officials at director level and above is only about one year, far shorter than those in major developed countries, which causes many problems such as low efficiency, lack of accountability and policy consistency, and low opportunity for accumulating expertise. Simple models are set up to analyze job rotation and other alternative personnel management systems. Analyses find that it would be desirable to have each individual experience various positions during the initial rotation period to find his/her own aptitude, and then accumulate expertise by settling in at a certain specialized field for a prolonged period of time based on the revealed aptitude in mid and high positions. This turns out to be in line with the structure of the Career Development Program which is being introduced. The model-based analysis of this paper distinguishes this study from preceding ones conducted in the traditional framework of personnel management study. Practical measures to mitigate the problems of frequent job rotation include rotating within the area of specialty, narrowing the scope of transfer, and reinforcing the minimum tenure period. However, since the current frequent rotation is fundamentally attributable to the rank system based on seniority, the present civil service classification system needs to be converted into a position classification system in the long run.

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Crystal Structure of a Bromine Sorption Complex of Dehydrated Calcium and silver Exchanged Zeolite A (칼슘 및 은 이온으로 치환된 제올라이트 A를 탈수한 후 브롬을 흡착한 결정구조)

  • Bae, Myung-Nam;Kim, Un-Sik;Kim, Yang
    • Korean Journal of Crystallography
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    • v.8 no.2
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    • pp.127-131
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    • 1997
  • The crystal structure of a bromine sorption complex of vacuum-dehydrated Ag+ and Ca2+ exchanged zeolite A(a=12,234(1) Å) has been determined by single-crystal X-ray diffraction methods in the cubic space group Pm3m. The crystal was prepared by flow method using exchange solution in which mole ratio of AgNo3 and Ca(NO3)2 was 1:150 with a total concentration of 0.05M. The crystal was dehydrated at 360℃ and 2 ×10-6 Torr for 2days, followed by exposure to 180 Torr of Br2 vapor for 20min. full-matrix least-squares refinements converged to the final error indices of R1=0.111 and R2=0.101 using 90 reflections for which I>3o(I). About 3.1 Ag+ ions and 4.45 Ca2+ ions lie on the two crystallographically nonequivalent three-fold axes associated with 6-ring oxygens. A total of six bromine molecules are sorbed per unit cell. Each bromine molecule approaches a framework oxide ions axially (Br-Br-O=171(2)', O-Br=3.25(6) Å; and Br-Br=2,61(8) Å by a charge-transfer interaction.

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The Crystal Structure of an Iondine Sorption Complex of Dehydrated Calcium and Silver Exchanged Zeolite A ($Ag^+$이온과 $Ca^{2+}$이온으로 치환한 제올라이트 A를 탈수한 후 요오드를 흡착한 결정구조)

  • Bae, Myung-Nam;Kim, Yang;Kim, Un-Sik
    • Korean Journal of Crystallography
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    • v.6 no.2
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    • pp.118-124
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    • 1995
  • The crystal structure of an iodine sorption complex of vacumm-dehydrated Ag+ and Ca2+ exchanged zeolite A(a=12.174(3)Å) has been determined at 21℃ by single-crystal X-ray diffraction techniques in the cubic space group Pm3m. The crystal was prepared by flow method for three days using exchange solution in solution in which mole ratio of AgNO3 and Ca(NO3)2 was 1:150 with total concentration of 0.05 M. The complex was prepared by dehydration at 360℃ and 2×10-6 Torr for 2 days, followed by exposure to about 14.3 Torr of iodine vaporat 80℃ for 24 hours. Full-matrix least-squares refinement converged to the final error indices of R1=0.082, R2=0.068 using 122 reflections for which I > 3σ(I). Two Ag+ ions, 1.1 Ag+ ions, and 4.45 Ca2+ ions per unit cell are located on three different three-fold axes associated with 6-ring oxygens. Two Ag+ ions per unit cell are in the large cavity, 1.399(4)Å from the (111) plane of three oxygens. Another 1.1 Ag+ ions are found at opposite sites. Six iodine molecules are sorbed per unit cell. Each I2 molecule approaches a framework oxide ion axially (O-I=3.43(2)Å, I-I=2.92Å, I-I-O;166.1(3)°), by a charge transfer complex interaction. Two Ag+ ions make a close approach to the iodine molecules (Ag-I ; 2.73(2)Å).

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A Study on The Principles and Philosophical Basis of 'Sa Sang Medicine' (사상의학(四象醫學)의 원리(原理)와 철학적(哲學的) 배경(背景)에 대(對)한 고찰(考察))

  • Song, Jeong-Mo
    • Journal of Sasang Constitutional Medicine
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    • v.4 no.1
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    • pp.5-29
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    • 1992
  • In this study, the author researched the process in which the philosophical basis of 'Sa Sang Medicine (四象醫學)' and its methodology build up the principles of Sa Sang Medicine, and then, examined how the principles were applied to the theoretical system of Sa Sang Medicine. The conclusion would be summarized as follows. 1. 'Nae Kyung Medicine (內經醫學)' was developed under the concept that the cosmos's order and its moving rule could be directly applied to that of human body, which corresponded to the 'Theory of Hwang-No (黃老之學)'. On the contrary, Sa Sang Medicine is a thoroughly human-oriented theory formed in the Confucianism system. 2. Lee Jae-Ma's Substantialism can be briefed into 'Mind 心' (Tae Keuk 太極), 'Mind-Body 心身' (Yang Eui 兩儀) and 'Activity-Mind-Body-Matter 事心身物' (Sa Sang 四象), which respectively represents one-elemented substance, two-elemented substance and four-elemented substance. Especially, Sa Sang was used as a basic framework in which he recognized all the objects and phenomena. So, most critical significance of his substantialism consists in the intention of Sa Sang type classifying. 3. By the method of Sa Sang type classifying, Lee Jae-Ma not only redefined the main concepts of confucianism and developed a unique philosophy of his own, but also, in the field of medical science, resystemized and re-explained the structure and function of human body. 4. From the recognition that Activity-Mind-body-Matter (Sa Sang) are four different existence forms of energy 氣 (or four variation types of energy), Yi Jae-Ma thinks that the viscera of human body have a vertical structure of 'four parts 四焦' (upper, mid-upper, mid-lower and lower parts) and its physiological function is operated by the rising and falling action of four energy presentations (sorrow 哀, anger 怒, joy 喜 and pleasure 樂). 5. In "Gyuk Chi Go 格致藁", Lee Jae-Ma understood the concept of joy, anger, sorrow and pleasure on the basis of nature-emotion theory 性情論 from the philosophical viewpoint. But, from the medical viewpoint of "Dong Eui Su Se Bo Won 東醫壽世保元", he understood them on the basis of vital energy theory. That is, sorrow, anger, joy and pleasure are expression of advance or reverse of nature vital-energy 性氣 and emotion vital-energy 情氣. 6. The rising and falling action principle of four energy presentations (sorrow, anger, joy and pleasure) which produces and helps each other is an identical principles of Sa Sang Medicine, distinguished from the Oh-Haeng 五行 circulating principle in Nae Kyung Medicine. Through this principle, Lee Jae-Ma explained the viscera physiology of human body, pathology & diagnosis and pharmacology.

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