• 대한기계학회논문집A
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• 제24권1호
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• pp.215-224
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• 2000

In order to reduce the variation effects of uncertainties in the engineering environments, new robust optimization method, which considers the uncertainties in design process, is proposed. Both design variables and system parameters are considered as random variables about their nominal values. To ensure the robustness of performance function, a new objective is set to minimize the variance of that function. Constraint variations are handled by introducing probability constraints. Probability constraints are solved by the advanced first order second moment (AFOSM) method based on the reliability theory. The proposed robust optimization method has an advantage that the second derivatives of the constraints are not required. The suggested method is examined by solving three examples and the results are compared with those for deterministic case and those available in literature.

• 한국해양공학회지
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• 제25권3호
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• pp.85-89
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• 2011

This study aimed to develop a wind turbine system for the domestic wind environments. The Taguchi method was applied to obtain the optimal design for a wind turbine with a wind-shield. The design parameters were defined to look for the shape of the wind turbine. Optimal parameters were determined on the basis of the analyzed level averages of the characteristics. According to the test results to which the optimal parameters were applied, the rpm improved. It was also found that a windshield 3/4 the size contributes to improving the efficiency of existing turbines.

• 한국실내디자인학회논문집
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• 제13권2호
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• pp.46-55
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• 2004

While transparency in general refers to the structure that is optically luminant or pleasant in its lightness, it is often synonymous with the concept of "modernistic." The advancement in construction and design technologies and the development of new materials with versatility adds even further diversity to transparency in architectural expression. The purpose of this study is to analyze various conceptions about transparency effects by comparing diverse expressions of visual lightness effects in space design. For this, I categorize and exemplify visual lightness effects of space applied to transparent materials. I argue that by utilizing transparent materials, the perception of space as well as boundaries between exterior and interior can be profoundly transformed. Space that overlaps through transparent boundaries creates atmosphere which deepens the architectural space environments.ironments.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.285-290
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• 2007

KALIMER-600 is a sodium cooled fast reactor with a fast spectrum neutron reactor core. The NSSS design has three heat transport systems of a PHTS (Primary Heat Transport System), a IHTS (Intermediate Heat Transport System) and a SGS (Steam Generation System). PHTS is a pool type and has a large amount of sodium in the pool. The mechanical design targets are maintaining the enough structural integrity for a seismic load of SSE 0.3g and the thermal and mechanical loads by the high temperature environments and an economical competitiveness when compared with other reactor types.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제8권1호
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• pp.61-67
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• 2002

It is the well-documented fact that most patients experience considerable stress in hospital. Stress is also a problem for families of patients, visitors and for hospital staffs. To promote wellness. It is fundamentally important that hospital be designed to foster copying with stress. By Literature review, this study presents stressors of patients, families, hospital staffs and various healing design elements. And then, it cross-checks the relations between stress-reducing conditions and healing design elements. Finally, this presents the healing design conditions for each stress-reducing conditions of patients, families and staffs.

• 한국조경학회지
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• 제22권3호
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• pp.163-174
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• 1994

In November of 1994, The Seoul Metropolitan Government celebrates its sixth centennial anniversary of becoming the capital city of Korea. In celebration of this anniversary, the Government decided to construct a plaza and sought design proposals in March of 1994. The authors collaborated on a design for the Time Capsule Plaza Competition and won fourth place among twenty-six entries. In the authors' design, the traditional oriental concept of time resonates within the site through the shape of a clock, a unique planting style, and an "Ancestral Tomb" which has a time capsule inside. The plaza is meant to be a symbol of the passage of time, the cycles of nature, and the repetitive actions of man. As for the spatial composition of the plaza, in accordance with the traditional Korean way of spatial arrangement, the plaza is divided into three parts: entry, primary, and secondary spaces. In reality, the plaza is created with the primary goal of providing modern outdoor space for people to rest and gather through the creation of pleasant environments and the introduction of traditional Korean garden elements.

• Journal of information and communication convergence engineering
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• 제9권2호
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• pp.166-171
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• 2011

This paper investigates the design issues of spectrum sensing in the cognitive radio (CR) networks of opportunistic unlicensed spectrum access. The cognitive radios can perform a communication using the incumbent user spectrum band without the interference caused by the cognitive radio users. In this case, the cognitive radios must know the real-time radio environments of the incumbent user spectrum band using the spectrum sensing, beacon signal, and geo-location database access. Then in this paper, we are going to provide spectrum sensing issues which include the sensing techniques, the regulatory requirements, the analysis of DTV detection threshold, and main considerations associated with the spectrum sensing design in cognitive radio systems. Also, this paper introduces design trade-offs in order to optimize the sensing parameters such as sensing time and sensing complexity.

• Journal of information and communication convergence engineering
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• 제15권2호
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• pp.117-122
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• 2017

Three-dimensional integrated circuits (3D ICs), starting with memory cubes, have entered the mainstream recently. The benefits many predicted in the past are indeed delivered, including higher memory bandwidth, smaller form factor, and lower energy. However, 3D ICs have yet to find their deployment in aerospace applications. In this paper we first present key design tools and methodologies for high performance, low power, and reliable 3D ICs that mainly target terrestrial applications. Next, we discuss research needs to extend their capabilities to ensure reliable operations under the harsh space environments. We first present a design methodology that performs fine-grained partitioning of functional modules in 3D ICs for power reduction. Next, we discuss our multi-physics reliability analysis tool that identifies thermal and mechanical reliability trouble spots in the given 3D IC layouts. Our tools will help aerospace electronics designers to improve the reliability of these 3D IC components while not degrading their energy benefits.

• 한국학교수학회논문집
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• 제7권2호
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• pp.67-79
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• 2004

교육/학습의 질이 실질적으로 향상되려면 연구가 교육 현장과 밀접하게 연계되어 실천 가능한 지식, 도구, 기술 등을 제공하여 주어야 한다. 실천적인 활용을 최우선으로 하는 설계-실험 연구의 다양한 연구 방법, 원칙, 주제 , 활동 내용 그리고 주요한 특징, 연구 사례 등을 소개한다.

• Steel and Composite Structures
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• 제4권4호
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• pp.265-280
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• 2004

In view of the mounting cost of rehabilitating deteriorating infrastructure, further compounded by intensified environmental concerns, it is now obvious that the evolvement and application of advanced composite structural materials to complement conventional construction materials is a necessity for sustainable construction. This study seeks alternative fill materials (polymer-based) to the much-limited cement concrete used in concrete-filled steel tubular structures. Polymers have been successfully used in other industries and are known to be much lighter, possess high tensile strength, durable and resistant to aggressive environments. Findings of this study relating to elasto-plastic characteristics of polymer concrete filled steel composite beams subjected to uniform bending highlight the enormous increase in stiffness, strength and ductility of the composite beams, over the empty steel tube. Moreover, polymer based materials were noted to present a wide array of properties that could be tailored to meet specific design requirements e.g., ductility based design or strength based design. Analytical formulations for design are also considered.