• Journal of Mechanical Science and Technology
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• 제15권2호
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• pp.232-238
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• 2001

Fast Fourier Transformation is employed to convert the head variation of a pipeline in the time domain to the amplitude of the frequency domain. Applying method of characteristics to a pipeline provides a significant frequency range for a surge introduced from the valve modulation. Inverse Fast Fourier Transformation and a Finite Impulse Response Filter can be used to remove any possible noise existing from the significant frequency range of an unsteady condition. A filtered signal shows higher potential for the inverse calculation of leakage detection than the noise-added signal does. The respective performances of Inverse Fast Fourier Transformation and a Finite Impulse Response Filter are compared in terms of leakage detection capability. Characteristics of the frequency range for multiple leakages were investigated to validate the effectiveness of the noise control method in the frequency domain.

• 유공압시스템학회논문집
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• 제8권1호
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• pp.1-9
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• 2011

The main design factors which effect on operating speed of linear actuator for valve operation are mass of plunger, electromagnetic motive force, inductance, and return spring, and these factors are not independent but related with each other in view point of design and electromagnetic theory. It is impossible to increase the operating speed by only change the value of any one design factor. The change of any one value results in change of any value related it in various design factors. This paper presents a speed increasing method of linear actuator using a solenoid design method by some governing equations which are composed of electromagnetic theory and empirical knowledge and permanent magnets as assistant material, and proved the propriety by experiments.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.499-502
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• 2005

Nowadays, the stripping work of form has generated some problems such as increasing total constructing cost result from delayed work schedule by the stripping work of form and environmental issues by wasting the debonded form. According to recent research for form work, it has studied about permanent form to solve economic and environmental problem which is commented above. In this study, high performance permanent form method was developed and tested by adopting COM and TEN specimens adopted on the Compression and Tensile section then the structural behaviour was investigated. In the test result, the specimen adopted the form showed better structural performance than control specimen in the point of ductility, failure mode and ultimate load.

• 대한한방내과학회지
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• 제11권2호
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• pp.16-21
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• 1990

The above results of clinical medication about Kwangdongtang and KG-500 were not done saparately but were done as the assistant way at the same time when nerbmedication(sangjae, tangjae, extractjae) was medicated From the point of lmpro vement of symptom, clinical pathologic test. patient's feeling, synthetic efficiency decision, safety degree, usefullness degree, it is thought that KG-500 is more useful than kwangdongtang at any aspect.

• Journal of Mechanical Science and Technology
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• 제15권7호
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• pp.876-888
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• 2001

For a large scaled optimization based on response surface methods, an efficient quadratic approximation method is presented in the context of the trust region model management strategy. If the number of design variables is η, the proposed method requires only 2η+1 design points for one approximation, which are a center point and tow additional axial points within a systematically adjusted trust region. These design points are used to uniquely determine the main effect terms such as the linear and quadratic regression coefficients. A quasi-Newton formula then uses these linear and quadratic coefficients to progressively update the two-factor interaction effect terms as the sequential approximate optimization progresses. In order to show the numerical performance of the proposed method, a typical unconstrained optimization problem and two dynamic response optimization problems with multiple objective are solved. Finally, their optimization results compared with those of the central composite designs (CCD) or the over-determined D-optimality criterion show that the proposed method gives more efficient results than others.

• 동의신경정신과학회지
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• 제13권2호
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• pp.11-19
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• 2002

Objectives : This study aimed investigation of mutual relation to a psychosomatic disorder and Sasang Constitutinal Medicine. Results : 1. A view of the body and mind, Sasang Constitutinal Medicine is similar to Mind-Body Medicine that a thought of the mind is the central idea. But a viewpoint of the mind to Sasang Constitutinal Medicine is based on Confucianism idea 2. The Nature and Emotion(性情)-a symbol of Happiness, Anger, Sorrow joy(喜怒哀樂) show a characteristic of man relate to an attack of a disease also take a disease itself. But Mind-Body Medicine recognize an attack of a disease caused only by the mind. 3. Sasang Constitutinal Medicine emphasize the care of health by respective The Nature and Emotion(性情) to the treatment and prevention of disease and drug therapy is an assistant. This is similar to an important meaning at psycho therapy-suggestive therapy, autogenic training, relaxation training etc in Mind-Body Medicine. Conclusions : Therefore, Sasang Constitutinal Medicine's clinical use in aspect of psychiatry, must to study human nature regard to korean traditional thought-Confucianism idea

• 여성건강간호학회지
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• 제12권1호
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• pp.12-21
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• 2006

Purpose: This study was performed to provide data for improvement in clinical practice education through analyzing the status of clinical practice education in maternity nursing in four year course nursing schools in Korea. Method: Analyzed subjects were 43 schools out of 53 four year course nursing schools in Korea. Result: Credits in theory and clinical practice are on the decline. The relationship between goals and areas of clinical practice was not sufficient. The department was not efficient in meeting the demands between theory and practice. The number of students in a group according to clinical areas were thoughtfully assigned, and clinical practice was performed based on real situations. Instructors for clinical practice used practice lecturers, part-time lecturers, preceptors, and assistant instructors including faculty. Methods of practice education and evaluation were varied. Conclusion: A suitable philosophy and goals of clinical practice education maternity nursing should be established at this point in time. Furthermore, a study should be performed to analyze the relationship between goals and contents of clinical practice for maternity nursing. In addition, a standardized tool should be developed to evaluate clinical practice.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.781-786
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• 2007

본 연구는 정부의 주거복지 지원계획과 관련한 공공임대주택의 양적인 공급 증가에 따라 유지관리의 필요성의 부각되고 있는 시점에서 현행 공공임대주택의 특성과 유지관리 시스템의 분석을 통해 장기적으로 유지관리방식의 문제점 개선과 효율성 향상을 위한 웹기반 유지관리 시스템으로의 발전가능성과 더불어 한계점도 파악해 보았다. 이 결과를 토대로 하여 PDA와 같은 IT를 활용한 유비쿼터스 장비의 이용가능성과 사용에 따른 기대효과를 제시함으로서 현재 연구${\cdot}$개발된 유지관리시스템의 문제점을 보완하여 사용자위주의 시스템을 제시하였다.

• 드라이브 ㆍ 컨트롤
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• 제19권4호
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• pp.62-69
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• 2022

Construction machinery is exposed to accidents such as collisions, narrowness, and overturns during operation. In particular, mobile crane is operated only with the driver's vision and limited information of the assistant worker. Thus, there is a high risk of an accident. Recently, some collision avoidance device using sensors such as cameras and LiDAR have been applied. However, they are still insufficient to prevent collisions in the omnidirectional 3D space. In this study, a rotating LiDAR device was developed and applied to a 250-ton crane to obtain a full-space point cloud. An algorithm that could provide distance information and safety status to the driver was developed. Also, deep-learning segmentation algorithm was used to classify human-worker. The developed device could recognize obstacles within 100m of a 360-degree range. In the experiment, a safety distance was calculated with an error of 10.3cm at 30m to give the operator an accurate distance and collision alarm.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권8호
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• pp.2666-2687
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• 2022

As a new alternative communication scheme in 5G, unmanned aerial vehicle (UAV) is used as a relay in the remote base station (BS) for assistant communication. In order to ameliorate the quality of the backhaul link, a UAV backhaul transmission scheme based on improved Nash equilibrium (NE) strategy is proposed. First, the capacity of air-to-ground (A2G) channel by the link preprocess is maximized. Then, the maximum utility function of each UAV is used as the basis of obtaining NE point according to the backhaul channel and the backhaul congestion. Finally, the improved NE strategy is applied in multiple iterations until maximum utility functions of all the UAVs are reached, and the UAVs which are rejected by air-to-air (A2A) link during the process would participate in the source recovery process to construct a multi-hop backhaul network. Simulation results show that average effective backhaul rate, minimum effective backhaul rate increases by 10%, 28.5% respectively in ideal A2G channel, and 11.8%, 42.3% respectively in fading channel, comparing to pure NE strategy. And the average number of iterations is decreased by 5%.