• 한국시뮬레이션학회논문지
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• 제6권1호
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• pp.25-40
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• 1997

This study deals with an autonomous generation of simulation codes for the design of processes of c CIM system based on the concept of model transformation. We assume we have a functional model of an organization which is developed using the well-known IDEF0 methodology. Then, a modeling methodology, called PROWD(PRocess flOW Description), is suggested to develop the flow processes of the organization. To Derive simulation specifications for the transformed PROWD model, we define a module of a "unit system" for each activity of PROWD model. Then specifications for system entities and resources are derived from input/control/mechanism/output and entity flows of PROWD model. Entitiy queues are defined from the sates and events of unit systems. Finally, SIMAN model frame is generated from those specifications through a suggested algorithm. The implementability and validity of the proposed approach is tested by developing a prototype of a computer-assisted design system on the operation processes of FMS installed at SNU-ASRI (Seoul National University-Automation and Systems Research Institute).nstitute).

• Bulletin of the Korean Chemical Society
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• 제7권1호
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• pp.63-66
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• 1986

Concentration dependences of the isotropic Raman line widths for the $ {\nu}_1$ (C-H and C-D) and the ${\nu}_2\;(C{\equiv}N)$ modes for $CH_3CN$ and $CD_3CN\;in\;CCl_4$ solutions have been investigated. For the ${\nu}_1$ modes, the dephasing seems to be a good description for the isotropic line broadening in $CCl_4$ solution even though the concentration fluctuation can reproduce the experimental results also. For the ${\nu}_2$ modes, the concentration fluctuation was the dominant mechanism for the concentration-dependent line broadening.

• Journal of Korean Neurosurgical Society
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• 제62권3호
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• pp.265-271
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• 2019

The expansion and folding of the cerebral cortex occur during brain development and are critical factors that influence cognitive ability and sensorimotor skills. The disruption of cortical growth and folding may cause neurological disorders, resulting in severe intellectual disability and intractable epilepsy in humans. Therefore, understanding the mechanism that regulates cortical growth and folding will be crucial in deciphering the key steps of brain development and finding new therapeutic targets for the congenital anomalies of the cerebral cortex. This review will start with a brief introduction describing the anatomy of the brain cortex, followed by a description of our understanding of the proliferation, differentiation, and migration of neural progenitors and important genes and molecules that are involved in these processes. Finally, various types of disorders that develop due to malformation of the cerebral cortex will be discussed.

• Wind and Structures
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• 제31권6호
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• pp.549-560
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• 2020

Methods for stochastic simulation of non-Gaussian wind pressure have increasingly addressed the efficiency and accuracy contents to offer an accurate description of the extreme value estimation of the long-span and high-rise structures. This paper presents a linear prediction and z-transform (LPZ) based Cumulative distribution function (CDF) mapping algorithm for the simulation of multivariate non-Gaussian fluctuating wind pressure. The new algorithm generates realizations of non-Gaussian with prescribed marginal probability distribution function (PDF) and prescribed spectral density function (PSD). The inverse linear prediction and z-transform function (ILPZ) is deduced. LPZ is improved and applied to non-Gaussian wind pressure simulation for the first time. The new algorithm is demonstrated to be efficient, flexible, and more accurate in comparison with the FFT-based method and Hermite polynomial model method in two examples for transverse softening and longitudinal hardening non-Gaussian wind pressures.

• Korean Membrane Journal
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• 제7권1호
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• pp.1-18
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• 2005

The permeate flux decline due to membrane fouling can be addressed using a variety of theoretical stand-points. Judicious selection of an appropriate theory is a key toward successful prediction of the permeate flux. The essential criterion f3r such a decision appears to be a detailed characterization of the feed solution and membrane properties. Modem theories are capable of accurately predicting several properties of colloidal systems that are important in membrane separation processes from fundamental information pertaining to the particle size, charge, and solution ionic strength. Based on such information, it is relatively straight-forward to determine the properties of the concentrated colloidal dispersion in a polarized layer or the cake layer properties. Incorporation of such information in the framework of the standard theories of membrane filtration, namely, the convective diffusion equation coupled with an appropriate permeate transport model, can lead to reasonably accurate prediction of the permeate flux due to colloidal fouling. The schematic of the essential approach has been delineated in Figure 5. The modern approaches based on appropriate cell models appear to predict the permeate flux behavior in crossflow membrane filtration processes quite accurately without invoking novel theoretical descriptions of particle back transport mechanisms or depending on adjust-able parameters. Such agreements have been observed for a wide range of particle size ranging from small proteins like BSA (diameter ${\~}$6 nm) to latex suspensions (diameter ${\~}1\;{\mu}m$). There we, however, several areas that need further exploration. Some of these include: 1) A clear mechanistic description of the cake formation mechanisms that clearly identifies the disorder to order transition point in different colloidal systems. 2) Determining the structure of a cake layer based on the interparticle and hydrodynamic interactions instead of assuming a fixed geometrical structure on the basis of cell models. 3) Performing well controlled experiments where the cake deposition mechanism can be observed for small colloidal particles (< $1\;{\mu}m$). 4) A clear mechanistic description of the critical operating conditions (for instance, critical pressure) which can minimize the propensity of colloidal membrane fluting. 5) Developing theoretical approaches to account for polydisperse systems that can render the models capable of handing realistic feed solutions typically encountered in diverse applications of membrane filtration.

• 한국정보과학회논문지:데이타베이스
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• 제31권2호
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• pp.195-204
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• 2004

최근 차세대 웹으로 시멘틱 웹이 부각되고 있다. 시멘틱 웹상에서는 정보 리소스들이 서로 의 미적으로 연결되어, 이를 컴퓨터가 처리할 수 있다. Resource Description Framework (RDF)는 이런 의미적 연결성을 제공한다. RDF는 웹 리소스들의 메타 데이타를 표현하기 위한 데이타 모델이다. 시멘틱 웹이 발전하기 위해서는 RDF 데이타를 효율적으로 관리하기 위한 방법이 가장 중요하다 할 수 있다. 본 논문에서는 RDF 데이타를 XML 데이타베이스 시스템에 저장하고 이를 검색하는 기법을 제안한다. XML 데이타베이스 시스템을 사용함으로써 XML 데이타와 RDF 데이타를 통합적이고 효율적으로 관리할 수 있다. 또한, 효율적인 검색 방법과 성능을 향상시킬 수 있는 방법들을 제안하고 있다. 논문에서 제안한 질의 처리 기법은 기존의 연구보다 나은 성능을 보여준다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제9권3호
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• pp.20-26
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• 2004

2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD)로 오염된 토양의 현장 광분해 정화 과정에서 가장 중요한 이동 메커니즘인 지표에서의 증발 및 광분해에 의한 유기 용매의 이류 상방향 이동에 대한 수식화와 모델 개발을 수행하였다. 각 유체 분포에 대한 다상 유동 효과, 구동력으로서의 중력, k-S-p 관계의 정확한 묘사를 위한 van Genutchen 방정식을 포함한 유한요소법 기반의 수치 모델을 제안하였다. 실험실 규모의 비포화 토양 컬럼 내 용매 이동에 중요한 영향을 미치는 인자들을 조사하기 위하여 수행한 계산의 결과들을 제시하였다. 중력은 고투수성 토양의 유체 분포와 증발에 상당한 영향을 미쳤다. 토양의 종류 또한 증발 과정 중 유체 포화도 분포에 큰 영향을 미친다. 용매의 이류 이동량은 증발량이 증가할수록 초기 물 포화도가 감소할수록 증가하였다. 본 연구에서 수행한 시뮬레이션은 개발된 모델이 토양 환경 내에서 유기 용매의 이류 이동에 영향을 미치는 다양한 인자들의 영향을 분석하는데 유용함을 보여준다.

• 한국의사학회지
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• 제24권1호
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• pp.73-96
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• 2011

The BianMaiFa chapter, which is the first chapter of SongBon ShangHanLun, is the scholarly description(專論) of the pulse and pathological mechanism but has not been studied and published yet. This study is about article 11-23 which is the second part of The BianMaiFa chapter. We compared the original texts within the editions, comparing and analyzing the annotations of successive dynastic medical group. The articles of The SongBon ShangHanLun BianMaiFa chapter 11-23 is consisted as is shown: article 11 12 13 state about a dignosis of yin-yang, deficiency-excess, fluid-humor from difference of a pulse shape and a sign of recovery from a disease, article 14 states about a prognosis of a disease according to a pulse, article 15 states about a pulse from which we predict a recovery, article 16 states about normal pulse according to season, article 17 states about ups and downs of a disease according to yin-yang of day and night, article 18 states about a location of a disease in connection with a pulse, article 19 states about a pathological mechanism of a diarrhea through a anterior tibial pulse(趺陽脈), a lesser yin pulse(少陰脈), article 20 states about a cause of disease, a symptom, a therapy about a floating and tight pulse(浮緊脈), article 21 states about a pathological mechanism of symptoms through a anterior tibial pulse(趺陽脈), article 22 states about a pulse, a pathological mechanism, symptoms caused by erroneous treatment, article 23 states about a pulse, a symptom, a therapy with internal heat. The BianMaiFa chapter 11-23 discussed a diagnosis, a prognosis of a disease, understanding of pathological mechanism through pulse. And The BianMaiFa suggests a various use of pulse.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제11권1호
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• pp.36-49
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• 2005

최근에 시멘틱 웹에 대한 관심과 기대가 증가함에 따라 시멘틱 웹 기반의 웹서비스인 시멘틱 웹서비스에 대한 연구가 활발히 진행되고 있다. 기존의 웹서비스는 XML 기반의 웹서비스 기술 언어인 WSDL을 사용하지만 시멘틱 웹서비스에서는 DAML-S와 같은 온톨로지 언어기반의 웹서비스 기술 언어를 사용한다. 시멘틱 웹서비스에 대한 연구는 웹서비스 검색, 웹서비스 구동, 웹서비스 구성, 웹서비스 실행 모니터링 등의 관점에서 수행되고 있다 특히, 시멘틱 웹서비스 검색은 시멘틱 웹서비스의 궁극적인 목적을 달성하기 위한 가장 기반이 되는 분야로 기존의 정보 검색과는 다른 특징들을 가지고 있다. 즉, 시멘틱 웹 기술 언어에 적합한 저장 시스템과 검색 방법이 요구된다. 이에 부합하여 관련된 시스템이 많이 개발되고 있으나 지능로봇 응용과 같은 제한된 메모리 공간 및 디스크 공간을 가지는 임베디드 환경에서 기존의 시스템을 적용하기에는 부적합하다. 이와 관련하여, 이 논문에서는 임베디드 시스템 환경에서 시멘틱 웹서비스 검색에 이용될 수 있도록 하기 위해서 DAML-S 서비스 지원을 위한 효율적인 DAML+OIL 문서 관리 시스템을 개발하였다. 또한, 우리는 이 논문에서 소개한 시스템의 특성을 다른 시스템과 비교하여 기술한다.

• 한국도서관정보학회지
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• 제20권
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• pp.61-105
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• 1993

For decades, general services and accounting officers have been dominant forces in collection development activities in college and university libraries in Korea. The role of certified librarians has been rather peripheral. This has been allowed by the fact that library acquisitions departments had to be headed by non-librarian general administrative officers by the government regulation. The philosophy behind this regulation was that acquiring library materials was not any different from simple purchasing act of other useful goods in the marketplace. In affiliation with the element of general administrative officers, domestic book-sellers also had a great influence in collection building activities in college and university libraries in Korea. This has been made possible by the fact that no other people could su n.0, pply library materials, especially foreign library materials. It has been pointed out for years that the mechanism in which general administrative officers and domestic book-sellers had a greater say in library acquisitions activities was especially inefficient in acquiring wanted materials in wanted speed and in wanted price. In this mechanism, books and periodicals were mere goods. They were not perceived as intellectual property holding information and knowledge in them. Since the student movement to revolutionize the library system of the Pusan National University, September 1987 to December 1988, the creative and progressive elements in this university library have been making great efforts to change the acquisitions system in this library into a more efficient one by putting certified librarians at the center of the whole acquisitions process. These efforts have been successful to a certain degree. In this discursive study of the case of the Pusan National University Library, I have tried to achieve a social description of the library process in which progressively motivated librarians succeeded in alienating administrative officers and book-sellers and in grasping in their hands the hegemony in the collection building aspect of library activities. It has been discovered that this was possible only when the librarians were mature enough to have their kind of professionalism, i.e., professional ethics and craftsmanship.