• 한국철도학회논문집
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• 제7권2호
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• pp.149-154
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• 2004

Pile Bridge Abutments constructed on a soft base are affected by a lateral flow. Laterl flow pressure acting on Pile is very difficult to calculate because of, interation of ground and Pile. So, it is different to estimate displacement of Pile Bridge Abutments. This paper studied about possibility of the displacement estimation of Pile Bridge Abutments by using the equivalent sheet pile wall theory that was Randolph proposed in 1981. Analysis program through using the SAGE CRISP that is FEM program. Analysis data used Centrifuge test results of Springman(1991), Bransby(1997) and Ellis(1997)'s paper. In conclusion, maxium displacement that is carried out by centrifuge test and numerical analysis has occured at the head of pile, as well as Maximum displacement of pile is closely similar. But the moment acting on pile of numerical analysis is under estimated compare to the centrifuge test. Through the comparative study, it is found that displacement estimation by equivalent sheet pile wall is in relatively good agreement with the results of centrifuge test.

• 산업기술연구
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• 제15권
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• pp.63-70
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• 1995

This paper presents an impact control algorithm for reducing the potentially damaging effects by interation of redundant manipulators with their environments. In the proposed control algorithm, the redundancy is resolved at the torque level by locally minimizing joint torque, subject to the operational space dynamic formulation which maps the joint torque set into the operational forces. For a given pre-impact velocity of the manipulator, the proposed approach is on generating joint space trajectories throughout the motion near the contact which instantaneously minimize the impulsive force which is a scalar function of manipulator's configurations. The comparative evaluation of the proposed algorithm with a local torque optimization algorithm with a local torque optimization algorithm without reducing impact is performed by computer simulation. The simulation results illustrate the effectiveness of the algorithm in reducing both the effects of impact and large torque requirements.

• 한국통신학회논문지
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• 제15권8호
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• pp.689-697
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• 1990

본 논문에서는 기존의 이중 케이블에서 전 이중방식 디지털 데이터 전송을 위한 적응 스토캐스틱 반복 알고리즘(Adaptive Stochasti Iteration Algorithm)을 제안하였다. 이 알고리즘을 이용한 반향제저기의 Step size는 반향의 크기에 따라서 변하므로 기존의 알고리즘에 의한 것 보다 10 배 이상의 높은 수렴율을 보였다. 그리고 이것은 기존의 반향 제거기 회로를 단순화 시키는 시퀸스 형태의 적응 디지털 필터와 결합하여 구현되며 LSI 수준으로 구현하기에 적합하다. 두 알고리즘에 대한 이론적인 분석을 제시하고 시뮬레이션 프로그램을 개발하였다.

• 약학회지
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• 제11권3_4호
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• pp.27-32
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• 1967

유화제또는 현탁화제로 쓰이고 있는 hydrophilic polymer의 일종인 acacia및 sodium alginate와 방부제와의 interaction에 관한 연구로서 Higuchi씨등 solubility mehtod를 실험방법으로 하여 고찰하였다. acacia는 용액중에서 혹종의 interation을 하나 o-hydroxybenzoic acid및 p-hydroxybenzoic acid의 methly, ethly, propyl, butyl ester 와는 그러한 interaction이 없다. sodium alginate는 butyl-p-hydroxybenzoate및 o-hydroxybezoic acid를 제외한 본실험에 사용한 방부제와는 용액내에서 interaction을 나타내었다. 방부제의 초농도와 acacia및 sodium alginate를 가하여 일정시간 반응시켜 평형에 도달했을때의 방부제의 농도와의 비인 K치는 acacia및 sodium alginate의 농도와 함수관계에 있음을 발견하였다.

• 대한가정학회지
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• 제38권3호
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• pp.71-84
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• 2000

This study firstly focused on development of an after-school program for school-aged children, and secondarily exploring the relationship between the after-school program and social competency of school-aged children. The program was composed of 10 two-hour sessions. The main goal of the program was to instill a sense of self-acknowledge, self-worth, responsibility and belonging to society and social activities. The subjects of this study were 29 children of first, second and third glades at the elementary schools in Seoul. This program was administered from March to May 1999. The data were analysed by frequency, mean, and paired t-test using the SAS program package. The major findings of this study were summarized as follows; There were significant differences in the degrees of social competency between before and after participating in the program(t=1,92 p<.05). The after-school program for school-aged children affect social competency variable as ‘initiative’(t=3,52 p<.001), but do not affect ‘sociability’, ‘responsibility’or ‘self-disclosure’. These results lead us to conclude that an after-school program of this type would be useful for developing peer-interation and for later social competency.

• 한국광학회지
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• 제10권2호
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• pp.114-119
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• 1999

편광에 기초한 Mach-Zehnder 간섭계 구조의 무작용 검출 시스템에 있어서, 두 가지 시스템의 결함, 즉 시스템 손실과 광자 검출기의 낮은 양자효율이 무작용 검출의 성능에 미치는 영향을 분석하였다. 이들 두 시스템 결함 모두가 얻을 수 있는 최대 검출효율을 제한하지만, 시스템 손실이 작을 때에는 양자효율은 덜 중요해짐을 보인다. 그리고 시스템 손실과 양자효율이 주어졌을 때, 얻을 수 있는 최대 검출효율을 예측하였다.

• 경영과정보연구
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• 제26권
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• pp.61-90
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• 2008

The purpose of this paper is to investigate the effects of anti-smoking advertising on attitude toward anti-smoking and behavioral intention to quit smoking in terms of audience's involvement with anti-smoking and knowledge on smoking. For this, a total of 10 hypothesis were established and statistically tested. According to the results, all but hypothesis 1-1(attitude toward anti-smoking is more favorable in the high involvement condition than in the low involvement condition) were unfortunately rejected. These results can be justified by theoretical explanations such as Hierarchy Effects Model or Elaboration Likelihood Model. In addition, some methodological reasons were provided as well.

• 소음진동
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• 제4권2호
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• pp.221-230
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• 1994

This paper deals with the dynamic stability and the nonlinear behavior of a check valve system. The nonlinear equations of motion of fluid-valve interation model are derived, which are composed of the unsteady Bernoulli's equation included the jet flow mechanism and equation of motion of a check valve formulated by one degree of freedom. Also, the derived equations of motion are nondimensionalized. According to the change of the nondimensional parameters, the stabilities of the system are analyzed, and the nonlinear interaction responses of the check valve and the passing flow rate are obtained. As the results, the stability charts are constructed for the variation of nondimensional parameters. It is shown that self-excited vibrations exist in a check valve system. And also the Hopf bifurcation and the periodic doubling are found. The presented theoretical model of a check valve system can be utilized to the design and operation of a piping system with the check valve.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 B
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• pp.720-725
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• 1995

The most important problems which should be considered in designing servo controllers are resonance effects and nonlinear friction. These problems exist in almost all the servo systems, especially for the robotic maniplators and numerical control systems and cause difficulties in designing controllers. In this paper, controller design procedure which employs $H_{\infty}$ control theory is proposed for the servo systems with these problems. Sometimes, for these systems, there is a possibility of limit cycles due to the interation between the nonlinear friction and integrator. To check the possibility of limit cycles, describing fuction method is used.

• 한국해양공학회지
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• 제13권1호통권31호
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• pp.51-61
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• 1999

When a structure is built on the ground under consolidation, the instant corresponding contact pressure which the upper structure exerts on the ground is established. But, as the consolidation of the ground proceeds, the contact pressure is changed because of the flexural rigidity of the upper structure. This varied contact pressure exerts influence on the consolidation behavior of the ground. And, this varied consolidation behavior exerts on the contact pressure in retum. This kind of interaction between the upper struture and the olwer ground under consolidation contimues till all the consolidation process in finished. So this problem cannot be defined as a linear problem. In this paper an approximation method which can analyse this non-linear interaction problem is proposed by the FEM.