• 수면정신생리
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• 제2권2호
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• pp.138-145
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• 1995

The causes of complicated chronic insomnia are very various and interact with vicious circle. Patient with this insomnia has generally a strong fear and frustration about failing to control of sleep and a deep mistrust toward doctor. To solve this complicated problems detailed history taking and sleep questionnaires are needed with objective polysomnography. Through these procedures, doctor should clarify causes of insomnia and explain them to patient in details and kindly. This process would be very helpful to restore the mistrustful relationship between patient and doctor and reduce patient's vague fear for insomnia. In treatment of complicated chronic insomnia, it is most important for patient to understand his problems and participate in the treatment schedule actively with assurance. Also doctor should encourage patient persistently not to be drop out. Most important factor for prognosis is patient's personality. Causes of complicated chronic insomnia are like these, overdose of hypnotics and sedatives, daily drinking alcohol with hypnotics, insomnia associated depression, delayed sleep phase syndrome, sleep state misperception, marked fear for insomnia, hyperarousal at bed, insomnia associated periodic leg movement and sleep apnea, chronic hypnotic insomnia, and immature personality. And possible treatments of these insomnias were discussed.

• Nuclear Engineering and Technology
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• 제39권3호
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• pp.207-214
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• 2007

A new Monte Carlo method for solving heat conduction problems is developed in this study. Differing from other Monte Carlo methods, it is a transport approximation to the heat diffusion process. The method is meshless and thus can treat problems with complicated geometry easily. To minimize the boundary effect, a scaling factor is introduced and its effect is analyzed. A set of problems, particularly the heat transfer in the fuel sphere of PBMR, is calculated by this method and the solutions are compared with those of an analytical approach.

• 한국경영과학회지
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• 제11권1호
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• pp.36-43
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• 1986

In this study, the fuzzy programming is extended to handle various types of membership functions by transformation of the complicated fuzzy programming problems into the equivalent crisp linear programming problems with single objective. It is well-known that the fuzzy programming problem with linear membership functions (i.e., ramp type) can be easily transformed into a linear programming problem by introducing one dummy variable to minimize the worst unwanted deviation. However, until recently not many researches have been done to handle various general types of complicated linear membership functions which might be more realistic than ramp-or triangular-type functions. In order to handle these complicated membership functions, the goal dividing concept, which is based on the fuzzy set operation (i. e., intersection and union operations), has been prepared. The linear model obtained using the goal dividing concept is more efficient and single than the previous models [4, 8]. In addition, this result can be easily applied to any nonlinear membership functions by piecewise approximation since the membership function is continuous and monotone increasing or decreasing.

• Journal of Ship and Ocean Technology
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• 제12권4호
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• pp.1-6
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• 2008

Nowadays, the computational capability and graphical power based on PCs increase very rapidly every year. As a result, the complicated engineering or scientific problems that could have only been handled by supercomputers a couple of decades ago can now be routinely run on PCs. Besides, the PCs can be assembled in parallel to increase its computational capability theoretically without limitation. The Web-based interface and communication tools are also being enhanced very rapidly and the real-time distance learning (E-Learning) and project cooperation on web get increasing attention. Using the-state-of-the-art computational method, a number of complicated and computationally intensive problems are being solved by PCs. The results can be well demonstrated on screen by graphics and animation tools. Those examples include the simulations of fully nonlinear waves, their interactions with floating bodies, global-motion analysis of multi-unit floating production system including complicated mooring lines and risers. Several examples will be presented in this regard. Also, Web and java-applet based educational tools have been developed at Texas A&M University for better understanding of waves and wave-body interactions. The background and examples of such Web-based educational tools published in Kim et al. (2003) are briefly introduced here.

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2004년도 정기학술대회
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• pp.37-72
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• 2004

Future Circuit Design means "Unimaginable Intricate Engineering Problems" Thus, Future Circuit Designers may be "Victims" of "Inexorably Complicated Signal Integrity Problems".(omitted)grity Problems".(omitted)tted)

• 한국안전학회지
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• 제22권5호
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• pp.50-56
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• 2007

In the past, a number of approaches, such as analytical, numerical or experimental methods, have been developed to deal with the soil-structure interaction effects. However, for many problems with complex geometry and material discontinuity most of approaches are nearly unpractical since it is difficult to model structures and complicated soil profiles precisely. This paper presents a soil-structure interaction analysis approach, which carl consider precisely characteristics of structures and complicated soil profiles. The presented approach overcomes the difficulties by adopting an unaligned mesh generation approach. From numerical examples, the applicability of the proposed approach is validated and dynamic responses of soil-structure systems subjected to earthquake loading are investigated considering characteristics of structures and complicated soil profiles.

• 한국콘텐츠학회논문지
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• 제16권3호
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• pp.476-487
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• 2016

심리정서행동의 복합적 문제를 나타내는 청소년의 수적인 증가와 욕구의 다양성에도 불구하고 이들을 통합적으로 지원하기 위한 구체적인 지원 프로그램은 거의 부재하며, 국내 전통적 사회서비스 전달체계는 복합적이고 복잡한 문제를 경험하는 청소년과 가족의 문제를 완화하지 못하는 한계를 갖고 있다. 따라서 본 연구는 복합적 문제를 나타내는 청소년을 위한 새로운 개입대안인 랩어라운드 모델의 국내적용 가능성을 탐색해보고자 한다. 이를 위해 사회과학의 대표적 데이터베이스 EBSCO를 활용하여 총 12편의 청소년에 적용된 사회복지분야 랩어라운드 연구를 선별하고, 이들의 연구동향을 분석하였다. 분석결과 첫째, 다양한 청소년 대상에 대한 랩어라운드 적용논문, 둘째, 랩어라운드의 일반적 특징과 관련된 논문, 셋째, 랩어라운드와 증거기반 실천 검증논문의 세 영역으로 구분되었고, 각 영역별로 논문에서 기술한 랩어라운드 특성을 제시하였다. 이러한 분석결과를 바탕으로 국내 적용가능한 랩어라운드의 실천적 대안을 제시하였다.

• Journal of Chest Surgery
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• 제17권3호
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• pp.424-431
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• 1984

• 한국안전학회지
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• 제21권3호
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• pp.87-93
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• 2006

When a structure is constructed at the site composed of soil, the behavior of a structure is much affected by the characteristics of soil. Therefore, the effect of soil-structure interaction is an important consideration in the design of a structure at the site composed of soil. Precise analysis of soil-structure interaction requires a proper description of soil profile. However, most of approaches are nearly unpractical for soil exhibiting material discontinuity and complex geometry since those cannot consider precisely complicated soil profiles. To overcome these difficulties, an improved integration method is adopted and enables to integrate easily over an element with material discontinuity. As a result the mesh can be generated rapidly and highly structured, leading to regular and precise stiffness matrix. The influence of soil profile on the response is examined by the presented method. It is seen that the presented method can be easily used on soil-structure interaction problems with complicated soil profile and produce reliable results regardless of material discontinuities.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 1999년도 추계학술대회-지능형 정보기술과 미래조직 Information Technology and Future Organization
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• pp.121-130
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• 1999

The objective of this paper is to apply Extended AND-OR Graph (EAOG)-related techniques to extract knowledge from a specific problem-domain and perform analysis in complicated decision making area. Expert systems use expertise about a specific domain as their primary source of solving problems belonging to that domain. However, such expertise is complicated as well as uncertain, because most knowledge is expressed in causal relationships between concepts or variables. Therefore, if expert systems can be used effectively to provide more intelligent support for decision making in complicated specific problems, it should be equipped with real-time inference mechanism. We develop two kinds of EAOG-driven inference mechanisms(1) EAOG-based forward chaining and (2) EAOG-based backward chaining. and The EAOG method processes the following three characteristics. 1. Real-time inference : The EAOG inference mechanism is suitable for the real-time inference because its computational mechanism is based on matrix computation. 2. Matrix operation : All the subjective knowledge is delineated in a matrix form, so that inference process can proceed based on the matrix operation which is computationally efficient. 3. Bi-directional inference : Traditional inference method of expert systems is based on either forward chaining or backward chaining which is mutually exclusive in terms of logical process and computational efficiency. However, the proposed EAOG inference mechanism is generically bi-directional without loss of both speed and efficiency.