• Geomechanics and Engineering
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• 제11권3호
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• pp.439-455
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• 2016

This paper presented solutions of displacement and stress for a circular opening which is reinforced with grouted rock bolt. It satisfies the Mohr-Coulomb (M-C) or generalized Hoek-Brown (H-B) failure criterion, and exhibits elastic-brittle-plastic or strain-softening behavior. The numerical stepwise produce for strain-softening rock mass reinforced with grouted rock bolt was developed with non-associative flow rules and two segments piecewise linear functions related to a principle strain-dependent plastic parameter, to model the transition from peak to residual strength. Three models of the interaction mechanism between grouted rock bolt and surrounding rock proposed by Fahimifar and Soroush (2005) were adopted. Based on the axial symmetrical plane strain assumption, the theoretical solution of the displacement and stress were proposed for a circular tunnel excavated in elastic-brittle-plastic and strain-softening rock mass compatible with M-C or generalized H-B failure criterion, which is reinforced with grouted rock bolt. It showed that Fahimifar and Soroush's (2005) solution is a special case of the proposed solution for n = 0.5. Further, the proposed method is validated through example comparison calculated by MATLAB programming. Meanwhile, some particular examples for M-C or generalized H-B failure criterion have been conducted, and parametric studies were carried out to highlight the influence of different parameters (e.g., the very good, average and very poor rock mass). The results showed that, stress field in plastic region of surrounding rock with considering the supporting effectiveness of the grouted rock bolt is more than that without considering the effectiveness of the grouted rock bolt, and the convergence and plastic radius are reduced.

• 한국국방경영분석학회지
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• 제3권2호
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• pp.49-77
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• 1977

Weapon systems are curcial instruments for the security of a nation and critical elements for the victory in a war. Since modern weapon systems tend to be capital-intensive with high precision and quality, they become more and more complex and diversified; their acquisition costs become huge; and their technological obsolescence becomes accelerated. Therefore, the systematic management of weapon acquisition process would be one of the most important defense tasks at the national level. To analyze such problems and find solutions, this paper has studied various aspects related to the efficient management of weapon system acquisition. After brief summarization of the general characteristics of weapon systems, their effectiveness, and developmental trend, the paper discusses the defense management policies and techniques for the weapon systems. Specifically, four alternative acquisition methods such as indigenous R & D, foreign purchase, co-production and joint-production are discussed and analyzed by systems approach. The systems analysis procedure to evaluate and select weapon acquisition method is as follows; 1) to analyze the merits and demerits of the alternative methods, 2) to screen unrealistic alternatives through the consideration of significant factors such as political, economic, military, technological, and social constraints, 3) to evaluate and select an optimal one among the remaining acquisition methods after the cost-effectivenss analysis. For the base of cost-effectivess analysis, cost analysis model as well as effectiveness analysis model of each acquisition method are developed.

• 한국중재학회지:중재연구
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• 제21권1호
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• pp.87-107
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• 2011

There are two methods to resolve conflicts related to constructions which are through lawsuits and ADR (Alternative Dispute Resolution) just like any other conflicts. Along with the special characteristics pertaining to the conflicts related to constructions, the advantages that ADR is in possession of such as its cost, duration and professionalism, resolving conflicts through ADR has been considered to be more logical than any other options recently. In Korea's case at present, the resolution of conflicts regarding constructions through ADR is mostly dependent on administrative mediation or through arbitration. However, in the case of the administrative mediation, its usage rate is very low due to problems caused by problems in its running and effectiveness. In the case of arbitration, the services of the Korean Commercial Arbitration Board is comparatively used more but because of the fact that arbitration relies on a single trial system and the fact that its executive powers while having the same effectiveness as the final ruling does not get acknowledged leads to the phenomena of avoiding its usage. In addition, in relation to the selective arbitration clause, the problem of effectiveness of the arbitrative agreement is becoming a hindrance to the activation and promotion of the arbitration process. Furthermore, in the case where the ordering body is the government, the public servant involved in the case avoiding the arbitration process because of concerns of being penalized by the internal and external audit within the institution is becoming a problem as well. These problems are not only limited to conflicts regarding constructions and there needs to be actions taken to promote the activation of ADR by enacting a basic law. The more important issue at hand however is offering a resolution measure that would be the most appropriate for users and this could probably be done only through actions such as implementing the American partnering system or the dispute adjudication board system so that they can supervise the resolution of conflicts through mediation, arbitration, and assistance as well as offering consultations regarding conflicts related to constructions.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.810-813
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• 2003

Wide spread using of mobile and handy electronic apparatus is giving rise to a question on the harmfulness of health and causing troubles when electical and electronic equipments are in use. This paper reports on the experimental results obtained by using a pliable and structured specimen that has a long shape aperture, made of stainless steel fibers. Based on the TEM mode transfer structure that was designed and manufactured through HFSS, we measured electromagnetic shielding effectives, where the network analyzer was applied. We could draw a conclusion from this research that the metal fabric showed a good electromagnetic shielding effect, mainly by means of the good reflex loss at the fiber surface. Even though the material itself possesses a good absorption loss. the specimen revealed that structural factors. e.g.. the shape of the aperture. the size of the aperture, etc., can have a more influence on the shielding effect than the components of material have. A special notice is required for modeling and analyzing the electromagnetic characteristics of metal fabrics, because there exists a strong possibility that multiple reflection can happen on the surface of metal fibers. which can presume a model of fiber bundle and fabric structure.

• 인간행동과 음악연구
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• 제3권1호
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• pp.1-11
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• 2006

미국에서는 1975년 장애아동교육법(Education for All Handicapped Children Act)이 시행되면서 특수교육 프로그램에서 일하는 음악치료사의 역할이 확대되기 시작하였고, 학령기 아동을 위한 음악치료의 역사는 반세기가 넘었다. 우리나라의 경우 2005년에 개정된 특수교육계획에서 특수교육이 필요한 학생의 치료교육에 대한 지원을 확대하고 각 지역 교육청별로 특수교육 지원센터를 두어 치료교육 교사를 배치 시행하는 안을 발표하여 학교 현장에서의 음악치료 보급이 시작되는 단계라 할 수 있다. 이에 본 연구는 2005년 특수교육계획이 시행된 지 6개월 정도 지난 시점에서 초등학교 음악치료와 관련된 특수교사들과 음악치료사들의 의견과 학교 현장에서의 음악치료 현황 및 실태는 어떠한지를 알아보고 그에 따른 개선점이나 문제점을 제시하는 데에 그 목적을 두었다. 이를 위해 본 연구와 관련된 선행 연구들과 문헌들을 조사 검토하고, 2005년 10월 18일부터 11월 2일에 걸쳐 특수교사 65명과 음악치료사 30명을 대상으로 초등학교 특수학급에서의 음악치료 현황과 인식도, 기대도 등에 관한 설문 조사를 실시하여 그 결과를 기술통계 처리하였다. 분석된 결과에 의하면, 특수교사와 음악치료사는 초등학교의 음악치료 필요성에 대해 인식하고 있으며 음악치료의 효과에 대해서도 긍정적인 기대를 보이는 것으로 나타났다. 또한, 음악치료 프로그램의 질을 높이고 체계화하기 위해서는 악기 및 음악치료실의 완비가 무엇보다도 시급한 것으로 나타났다. 이를 위해 국가나 학교 차원에서의 적극적인 행 재정적 지원이 있어야 한다는 지적도 있었다. 특수학교나 특수학급을 비롯한 지역사회 복지관, 조기교육 현장 등 장애아동이 있는 모든 곳에서 치료교육에 대한 학부모들의 요구는 최근 들어 증가하고 있다. 본 연구는 초등학교 현장에서 치료와 교육을 접목시킨 음악치료교육에 대한 전반적인 조사를 통해 초등학교에서 음악치료교육의 필요성을 제시하였다는 데 그 의의가 있다고 하겠다.

• 정보관리연구
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• 제20권2호
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• pp.100-128
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• 1989

산업연구원(産業硏究院)의 기존(旣存) 컴퓨터 자원(資源)을 이용(利用)하여 정보자료실(情報資料室)의 자료관리(資料管理) 및 이용자(利用者)서비스 측면(側面)의 효율성(效率性)을 기할 수 있는 자료관리(資料管理)토탈시스템구축(構築)을 목표(目標)로 시스템을 전문도서(專門圖書)시스템과 연속간행물(連續刊行物)시스템으로 나누어 개발(開發)하였다. 본고(本稿)에서는 현재 운용(運用)되고 있는 전문도서(專門圖書)시스템의 목록(目錄), 검색(檢索) 및 대출(貸出)시스템에 대해 기술하였다.

• Journal of international Conference on Electrical Machines and Systems
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• 제3권2호
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• pp.155-161
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• 2014

Industrial Static Var Generator (SVG) is typically applied at or near the load center to mitigate voltage fluctuation, flicker, phase unbalance, non-sine distortion or other load-related disturbance. Special attention is paid to the influence of grid voltage quality on SVG current, the non-sine distortion and unbalance of grid voltage causes not only the AC current distortion and unbalance but also the DC voltage fluctuation. In order to let the inverter voltage contain the fundamental negative sequence and harmonic component corresponding to the grid voltage, a new dual-loop control scheme is proposed to suppress the influence in this paper. The harmonic and negative sequence voltage decomposition algorithm and DC voltage control are also introduced. All these analyses can guide the practical applications. The simulation results verify the feasibility and effectiveness of the present control strategy and analyses.

• 한국콘텐츠학회논문지
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• 제5권4호
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• pp.197-203
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• 2005

멀티플랫폼을 지향하는 유비쿼터스 e-Loaming 시스템에서는 보다 다양한 매체를 통한 온라인 학습이 이루어지기 때문에 상호작용 촉진이 매우 중요하다. 본 논문에서는 온라인 학습에서 매우 절실히 요구되는 상호작용 촉진 학습 설계를 사이버강의에 적용하고 피드백을 통해서 고찰하였다. 향후에는 감성공학과 같은 기반기술을 적용한 보다 효율적인 상호작용을 지원하는 학습 설계가 모색되어야 할 것이다.

• 제어로봇시스템학회논문지
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• 제10권7호
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• pp.611-617
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• 2004

This paper presents a simple method of rotational motion estimation and correction for roll axis stabilization of an image. The scheme first computes the rotation center by taking least squares of selected local velocity vectors, and the rotational angle is found from special subset of motion vectors. Roll motion correction is then performed by the nearest neighbor interpolation technique. To show the effectiveness of our approach, the synthetic and real images are evaluated, resulting in better performance than the previous ones.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2529-2534
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• 2003

A quadruped walking robot has a superior adaptablility as well as highly adaptable mobility in various environments. These special advantages are outstanding in the mobile robot group. In this work, we introduce the method for omni-directional gait and rotational gait which is the generalized control algorithm to perform any direction commands. In addition, to improve the stability of quadruped walking robot, we performed the optimization between walking angle and sequence of feet. The proposed ideas are applied to the actual design of MRWALLSPECT III(Multifunctional Robot for Wall inSpection version 3) that is designed to inspect of the large surface of industrial utilities. By implementing the proposed idea on the robot, it’s effectiveness is experimentally confirmed.