• International Journal of Safety
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• 제2권1호
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• pp.34-38
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• 2003

The lower and upper flash points of the flammable binary system, butylacetate+2-propanol were measured by air blowing tester. The shape of the concentration-temperature region of flash depended on the components of the mixture in solution. The experimental data were compared with the values calculated by the reduced model under an ideal solution assumption and the flash point-prediction models based on Van Laar equation. Good qualitative agreement was obtained with these models. The prediction results of these models can thus be applied to incorporate inherently safer design for chemical process, such as the determination of the safe storage conditions for flammable solutions.

• 한국국방경영분석학회지
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• 제26권2호
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• pp.75-89
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• 2000

This paper deals with complex system theory to describe guerrilla warfare situation using EINSTein (Enhanced ISAAC Neural Simulation Tool) simulation model. EINSTein model is an agent-based artificial "laboratory" for exploring self-organized emergent behavior in land combat. Many studies have shown that existing Lanchester equations used in most guerrilla warfare models do not describe changes of combat units, real guerrilla warfare situation and qualitative factors in combat. Future warfare will be information warfare with various weapon system and complex combat units. We have compared and tested results with Lanchester models and EINSTein model. And the EINSTein model has been applied and analyzed to guerrilla warfare model (C4I facilities, coastal, urbanized terrain critical facilities defense). The results show that the EINSTein model has a possibility to apply and analyze guerrilla warfare more properly than Lanchester models.

• 한국전기전자재료학회논문지
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• 제15권1호
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• pp.7-14
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• 2002

In this paper, neutral networks are used to build models of oxide film etched In CHF$_3$/CF$_4$ with a magnetically enhanced reactive ion etcher(MERIE). A statistical 2$\^$4-1/ experimental design plus one center point was used to characterize relationships between process factors and etch responses. The factors that were varied include radio frequence(rf) power, pressure, CHF$_3$ and CF$_4$ flow rates. Resultant 9 experiments were used to train neural networks and trained networks were subsequently tested on its appropriateness using additionally conducted 8 experiments. A total of 17 experiments were thus conducted for this modeling. The etch responses modeled are dc bias voltage, etch rate and etch uniformity A qualitative, good agreement was obtained between predicted and observed behaviors.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제6권1호
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• pp.45-57
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• 2000

현재 널리 사용되고 있는 네트워크 관리 기술들은 서로 다른 관리 정보 모델을 정의하여 사용하거나 다른 관리 프로토콜을 사용하여 통신하므로 호환성을 가지지 못한다. 이런 문제를 해결하기 위해서 여러 분산 패러다임들의 적용을 통해 이전 모델의 개선을 위한 연구들이 이루어지고 있다. 그러나 기존의 연구들은 그 모델의 효용성을 양적으로 제시하기보다는 질적이고 사고 중심적으로 제시하였다. 그래서, 본 논문에서는 모빌 에이전트 패러다임을 이용한 네트워크 관리 모델을 제안하고 그 적용의 양적인 실효성을 알아본다. 그 실효성의 양적 비교를 위해 여러 분산 패러다임과 새로이 제안하는 모델간의 효용성을 각 모델의 통신량 패러메터 모델을 통한 통신량 크기 비교를 통해서 제시한다.

• 인지과학
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• 제10권4호
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• pp.63-70
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• 1999

자동차 충돌 사고 재구성이란 사고 상황으로부터 가능한 모든 정보를 수집, 분석하여 충돌로 인한 사고 거동 및 원인을 규명하는 작업이다. 본 논문에서는 자동차 사고 재구성에 직접 적용이 가능하도록 개발된 충돌 재구성 시스템을 소개하고자 한다. 본 시스템은 정량적 충돌 재구성 시스템과 정성 적 충돌 추론 시스템을 통합하여, 상호 보완적 역할을 통해 기존의 단일 시스템이 갖는 제한점들을 극복할 수 있었다. 통합된 시스템은 충돌로 인한 거동에 대한 정확한 예측과 아울러 정성 적 충돌 거동 묘사를 제공한다. 강체 동역 학 이론에 기초한 충돌 역 해석 과정 시 정성 적 시뮬레이션을 통해 잘못된 가설을 검증하여, 모순되는 가설을 초기 단계에서 찾아낼 수 있게 하였다. 또한 이 과정에서 인과 관계에 근거한 정성 적 설명을 제공함으로써, 수치 모델에 의해 예측된 결과의 이해를 도울 수 있었다. 본 시스템은 자동차 충돌 사고의 충돌에 적용되어 유효성을 입증할 수 있었다.

• Human Ecology Research
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• 제55권6호
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• pp.581-592
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• 2017

This study investigated the occupational experiences of social workers in child care facilities. The participants of the study were six social workers in child care facilities. This qualitative research used a Consensual Qualitative Research (CQR) method that and classified the main findings into five categories and twelve sub-themes. This study revealed that child care professionals define themselves as "caregivers" and "role models." Positive effects of institutional life on a child were forming peer relationships and being able to use diverse services while negative effects included acquiring a social stigma, having problems in developing attachment between a child and a surrogate caregiver, developing passive attitude and weak will power from communal living. Meanwhile, conflicts with children and poor working conditions led to burnout for caregivers. Our recommendations on the direction of change for the facilities are: categorizing admitted children, supporting restoration of family functions, reinforcing support for children's preparation for an independent life, and developing expertise. This paper provides a better understanding of child care facilities as well as encourages further social discourse on institutionalized children in order to promote policy making and implementation.

• 한국시스템다이내믹스학회:학술대회논문집
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• 한국시스템다이내믹스학회 1999년도 창립학술대회발표논문집
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• pp.105-132
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• 1999

If a system such as a port has a large boundary and complexity, and the system's substance is considered as a black box, forecast accuracy will be very low. Furthermore various components in a port exert significant influence on each other. To copy with these problem the form of structure models were introduced by using SD method. The Competitive Ports Model had several sub-systems consisting of each Unit Port models, and each Unit Port model was made by quantitative, qualitative factors and their feedback loops. The fact that all components of one port have influence on the components of the other ports should be taken into account to construct Competitive Port Models. However, with the current approach that is impossible, and in this paper, therefore, models were simplified by HFP adapted to integrate level variables of unit port models. Although many studies on modelling of port competitive situation have been conducted, both theoretical frame and methodology are still very weak. In this study, a new algorithm called ESD(Extensional System Dynamics) for the evaluation of port competition was presented, and applied to simulate port systems in northeast Asia.

• 물과 미래
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• 제23권4호
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• pp.487-497
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• 1990

원자력·화력, 제철소 등의 임해공업시설로부터 온수 방출의 확산에 대한 정성, 정량적 예측은 환경관리 및 냉각수 취·배수로 설계에 매우 중요하다. 본 연구는 난류 및 부력효과가 강한 온배수의 주요 물리적 특성을 규명하고 실무에 많이 사용되고 있는 MIT 및 PDS 적분모델의 비교평가를 실시하였다. 일반적으로 MIT 및 PDS 모델은 성층화되지 않은 수역에서 주위수 및 제트 방출각도를 고려하여 온배수 거동을 산정하는 모델이다. 해석결과는 그 구성의 상이성에 의해 매우 다름이 규명되어, 온배수의 정확한 산정을 위해서는 난류모델을 이용한 수치모델의 개발 및 이의 적용이 요구된다.

• Structural Engineering and Mechanics
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• 제71권6호
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• pp.739-749
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• 2019

This article deals with the application of reliability analysis for determining the safety of simply supported beam under the uniformly distributed load. The uncertainties of the existing methods were taken into account and hence reliability analysis has been adopted. To accomplish this aim, Generalized Regression Neural Network (GRNN), Extreme Learning Machine (ELM) and Gaussian Process Regression (GPR) models are developed. Reliability analysis is the probabilistic style to determine the possibility of failure free operation of a structure. The application of probabilistic mathematics into the quantitative aspects of a structure and improve the qualitative aspects of a structure. In order to construct the GRNN, ELM and GPR models, the dataset contains Modulus of Elasticity (E), Load intensity (w) and performance function (${\delta}$) in which E and w are inputs and ${\delta}$ is the output. The achievement of the developed models was weighed by various statistical parameters; one among the most primitive parameter is Coefficient of Determination ($R^2$) which has 0.998 for training and 0.989 for testing. The GRNN outperforms the other ELM and GPR models. Other different statistical computations have been carried out, which speaks out the errors and prediction performance in order to justify the capability of the developed models.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.1142-1149
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• 2003

Various organizational factors effect successful implementation of IT enabled business transformation. Among them, the most critical success factor is deemed to overcoming change management problem. Lots of studies have been made on Implementation methodologies and business process formalizations to encourage organizational members to accept new business process changes. However, the logic or process redesign still depends on qualitative problem solving techniques mostly depending on basically human intuition such as brainstorming. cause-and-effect analysis. and so on. In this paper, we focused on developing analytic framework to design to-be business process structure. which can complement qualitative problem solving procedures. With effective use of IT as an enabler, we provide algorithmic framework applicable to designing various business process changes such as process automation, business process resequencing, and more radical process integration. The framework follows dynamic programming approach in the literature, which is based on the decision making paradigm of organizations to abstract business processes as quantitative decision models. As such, our research ran fill the gap of limited development of theory based analytic methodologies for business process design, by providing objective rationale to reach the consensus among the organizational members including senior management.