• 대한전기학회논문지
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• 제39권4호
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• pp.371-379
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• 1990

The decoupling problem has a great practical importance in that it simplifies greatly the control of a given system by reducing the multi-input multi-output systems. In this paper, we derive the necessary and sufficient conditions for decoupling 2-D F-MM II via state feedback. For the general case, the problem of determining the feedback matrix F involves the solution of nonlinear algebraic equations. Under certain conditions, however, it is shown that an explicit formula for F may be derived. In comparsion with the method for FM, it appears that this method for F-MM II is more general and the algorithm is simpler.

• 한국중재학회지:중재연구
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• 제25권3호
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• pp.135-154
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• 2015

The European Union has adopted the ADR Directive and ODR Regulation in 2013 with the purpose to strengthen the e-commerce within the EU. Not covered by these legislations is the trade in the B2B sector. The author examines the question of whether online ADR under the currently applicable legal framework would be possible in Germany. At the center of his review is the possibility of an arbitration clause which refers exclusively to an online ADR scheme, may be included in the General Terms and Conditions of an online trader.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 가을 학술발표회 논문집
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• pp.325-332
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• 1999

As part of the conceptual disign of cable and membrane structures, the adequate shape is decisive with respect to load bearing behaviour and aesthetic expression of the structure. The force densities which are the force-length ratio are very useful parameters for the description of equilibrium state of any general cable-net structures. Because equilibrium states are obtained by solving linear equations the force desity method has a advantage compared with other solution strategies. But if there are futher restrainted conditions in force density the linear method will be extended to nonlinear one. The numeriacl methods are based upon least square and general inverse method for sieving nonlinear eqations. In this paper, the results from two methods is compared through several examples.

• 전산구조공학
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• 제4권1호
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• pp.121-132
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• 1991

본 연구는 철근콘크리트 뼈대구조물의 실제적인 단부경계조건을 고려한 철근콘크리트 기둥에 대한 인접부재의 강성을 비선형거동과 부합시켜 해석하고, 인접부재의 단부구속효과를 고려한 중심축하중을 받는 장주의 극한강도를 해석하고저 해석모델을 정립하여 보-기둥의 2차강성매트릭스 해석법에 의하여 이론적으로 해석하는데 있다.

• 대한기계학회논문집
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• 제13권3호
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• pp.554-560
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• 1989

본 연구에서는 실제 운행시에 발생할 수 있는 최악의 경우를 모든 반기의 무게를 집중질량으로 고려한 충실한 해석을 통하여 구해보고자 하였다. 이를 위하여 하나의 구간에 여러 개의 집중질량이 달린 경우에 대한 선로방정식을 유도하였고, 최소반력을 구하기 위한 문제를 최적설계 문제로 정의한 다음, 이를 체험적 최적설계 기법(heuristic optimization technique)을 통하여 해결하였다. 또한 예재해석을 통하여 최악의 상태가 발생하게 될 일반적인 조건을 구하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.604-607
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• 2005

The free vibration of solid circular plates has been studied using the differential transformation method(DTM). The effects such as mass at edge and elastic restraints have been considered. In order to avoid the singularity problem at the solid circular center two regularity conditions were applied with respect to the number of circumferential nodal line. The non-dimensional natural frequencies of the general circular plates were obtained for various boundary conditions. The results obtained by this method were compared with previous works. DTM showed fast convergency, accuracy, efficiency and validity in solving vibration problem of general circular plates.

• Structural Engineering and Mechanics
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• 제69권4호
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• pp.427-437
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• 2019

In this study, an alternative solution procedure presented by using variational methods for analysis of shear deformable functionally graded material (FGM) beams with mixed formulation. By using the advantages of $G{\hat{a}}teaux$ differential approaches, a refined complex general functional and boundary conditions which comprises seven independent variables such as displacement, rotation, bending moment and higher-order bending moment, shear force and higher-order shear force, is derived for general thick-thin FGM beams via shear deformation beam theories. The mixed-finite element method (FEM) is employed to obtain a beam element which have a 2-nodes and total fourteen degrees-of-freedoms. A computer program is written to execute the analyses for the present study. The numerical results of analyses obtained for different boundary conditions are presented and compared with results available in the literature.

• 대한조선학회논문집
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• 제51권6호
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• pp.489-494
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• 2014

Estimation of correct ice load under various operating conditions is important during the design and the operation stages of an icebreaker. Normal operating conditions are expected from the official field ice trials and also from general ice transit action. In this paper ice load for the Korean icebreaking research vessel, ARAON, under normal operating condition, is discussed. Published ice load data from full-scale sea trials of six icebreakers were analysed to derive an empirical ice load prediction formula. The IBRV ARAON had sea ice trials during 2010 and 2012 summer season. Strain gauge signal were recorded during her icebreaking voyage and the measured strain data were converted to the equivalent hull stress values. The effect of ARAON's speed in ice and the hull stresses are investigated. By comparing the empirical formula and ice load calculation based von measured data, it is recommended to use the empirical ice load estimation formula for the initial design stage.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.100-104
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• 1993

In Part 1, we derived robust stability conditions for an LTI interconnected to time-varying nonlinear perturbations belonging to several classes of nonlinearities. These conditions were presented in terms of positive definite solutions to LMI. In this paper we address a problem of synthesizing feedback controllers for linear time-invariant systems under structured time-varying uncertainties, combined with a worst-case H$_{2}$ performance. This problem is introduced in [7, 8, 15, 35] in case of time-invariant uncertainties, where the necessary conditions involve highly coupled linear and nonlinear matrix equations. Such coupled equations are in general difficult to solve. A convex optimization approach will be employed in this synthesis problem in order to avoid solving highly coupled nonlinear matrix equations that commonly arises in multiobjective synthesis problem. Using LMI formulation, this convex optimization problem can in turn be cast as generalized eigenvalue minimization problem, where an attractive algorithm based on the method of centers has been recently introduced to find its solution [30, 361. In the present paper we will restrict our discussion to state feedback case with Popov multipliers. A more general case of output feedback and other types of multipliers will be addressed in a future paper.

• 대한한의학회지
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• 제32권6호
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• pp.67-73
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• 2011

Objectives: To examine the overview of fatigue-related health conditions in the Korean general population. Methods: Data were collected from 2,203 adults (1,126 men and 1,077 women) via a self-reporting questionnaire and their sleeping, exercise, stress, physical problems, use of functional food, and fatigue status were analyzed. Results: The average sleeping hours was about $6.6{\pm}2.0$ hrs per day, and 24.3% of subjects didn't exercise (over 30 min) in a week. Around 16.5% of subjects were under severe stress, and 46.1% (36.9% male vs. 55.6% female) had had trouble with at least one form of physical distress including dyspepsia, headache or muscular pain. 45.4% (37.2% male vs. 53.9% female) of subjects used functional supplements. 46.3% (42.8% male vs. 50.0% female) of subjects complained of chronic fatigue, and they were significantly different compared with no-fatigue subjects regarding severe stress status (8.6% vs. 24.0%), frequency of physical distress (33.2% vs. 69.9%), and use of functional supplements (41.6% vs. 49.8%). Conclusion: This result first reports the features of fatigue-related health conditions including prevalence of chronic fatigue in the Korean population. This data could be helpful to develop fatigue-focused traditional Korean medicine in the future.