• 한국농공학회지
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• 제39권2호
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• pp.9-18
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• 1997

Abstract This paper presents a heuristic method for optimal design of water distribution system with multiple sources and potential links. In multiple source pipe network, supply rate at each source node affects the total cost of the system because supply rates are not uniquely determined. The Linear Minimum Cost Flow (LMCF) model may be used to a large scale pipe network with multiple sources to determine supply rate at each source node. In this study the heuristic method based on the LMCF is suggested to determine supply rate at each source node and then to optimize the given layout. The heuristic method in turn perturbs links in the longest path of the network to obtain the supply rates which make the optimal design of the pipe network. Once the best tree network is obtained, the frequency count of reconnecting links by considering link failure is in turn applied to form loop to enhance the reliability of the best tree network. A sample pipe network is employed to test the proposed method. The results show that the proposed method can yield a lower cost design than the LMCF alone and that the proposed method can be efficiently used to design irrigation systems or rural water distribution systems.

• 정보처리학회논문지C
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• 제9C권5호
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• pp.699-708
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• 2002

멀티미디어 연출을 재생하는 단말기나 통신망이 다양해짐에 따라 멀티미디어 데이터를 저장하고 있는 근원지의 데이터 서비스 품질과 재생하는 목적지의 서비스 품질이 다른 경우가 많이 발생하고 있다. 이러한 멀티미디어 연출을 재생하기 위해서 근원지의 데이터를 목적지에서 요구하는 재생 서비스 품질에 맞추어 변환하는 과정이 반드시 필요하다. 문제는 하나의 멀티미디어 연출 프로그램이라도 그것이 재생되는 단말기나 통신망의 환경에 따라 변환 경로가 달라져야 한다는 점이다. 즉 고정된 변환 경로를 사용할 수 없고 재생되는 단말기나 통신망이 정해지면 그에 맞는 변환 경로를 다시 생성해야 한다는 점이다. 본 논문은 주어진 변환 자원과 통신망을 고려하여 근원지 데이터를 목적지에서 요구하는 재생 서비스 품질에 맞게 변환하는 경로를 찾는 알고리즘과 그 경로가 목적지에서 요구하는 서비스 품질에 맞게 재생 가능한지를 검사하는 방법을 제시한다. 본 논문이 제시한 변환 경로를 생성하는 알고리즘은 변환 자원과 변환 규칙을 문맥 자유 문법(Context Free Grammar)으로 기술 할 수 있도록 함으로 변환 경로를 컴파일러 기법을 이용하여 생성할 수 있도록 하였다. 그리고 재생 가능성을 검사하기 위하여 변환 과정에서 소요되는 시간과 지연 등을 계산하는 방법과 요구하는 시간 내에 이루어 질 수 있는지 검사하는 방법을 제안하였다. 그리고 이러한 방식을 실험실에서 개발한 Transcore라는 멀티미디어 스트림 엔진과 VIP라고 하는 저작도구에 구현하였고 간단한 시나리오에 적용한 결과를 마지막으로 기술하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.19-19
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• 2005

This paper reports a novel magnetic force-based microfluidic immunoassay using microbeads and magnetic nanoparticles. The magnetic force-based immunoassay was devised first and successfully applied to detect the rabbit IgG as the model analyte of microfluidic sandwich immunoassay. The microchannels were fabricated by poly(dimethysiloxane) (PDMS) molding processes and bonded on a slide glass by plasma treatment. At the part of the inlet, sample solution was hydrodynamically focused. The focused microbeads of sample solution were flowed through the 150 ${\mu}m$ width channel of outlet. However, when the microbeads are conjugated with the superparamagnetic nanoparticles under the applied magnetic fields, they will switch their flow path and flow through the 95 ${\mu}m$ width channel of outlet. The movements of microbeads conjugated with magnetic nanoparticles were demonstrated by magnetic field $gradients.^{1)}$ High magnetic field gradients using micro electromagnets could be applied to this detection method for high sensitivity and lower detection limit. In addition, the multiplexed $immunoassay^{2)}$ using an encoded microbead which is immobilized with a certain antibody could be possible using this detection principle.

• Structural Engineering and Mechanics
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• 제74권3호
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• pp.313-323
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• 2020

Non-destructive tests are commonly used in construction industry to access the quality and strength of concrete. However, till date there is no non-destructive testing method that can be adopted to evaluate the bond condition of reinforced concrete beams. In this regard, the presented research work details the use of ultra-sonic pulse velocity test method to evaluate the bond condition of reinforced concrete beam. A detailed experimental research was conducted by testing four identical reinforced concrete beam samples. The samples were loaded in equal increments till failure and ultra-sonic pulse velocity readings were recorded along the length of the beam element. It was observed from experimentation that as the cracks developed in the sample, the ultra-sonic wave velocity reduced for the same path length. This reduction in wave velocity was used to identify the initiation, development and propagation of internal micro-cracks along the length of reinforcement. Using the developed experimental methodology, researchers were able to identify weak spots in bond along the length of the specimen. The proposed method can be adopted by engineers to access the quality of bond for steel reinforcement in beam members. This allows engineers to carryout localized repairs thereby resulting in reduction of time, cost and labor needed for strengthening. Furthermore, the methodology to apply the proposed technique in real-world along with various challenges associated with its application have also been highlighted.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1999년도 제29회 춘계학술대회
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• pp.38-46
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• 1999

Numerical methods are procured for evaluating the contact stresses, the dissipation of friction energy density and the fatigue cracking emanated from the contact surface under the partial slip condition. A rounded punch is used for the indenter pressing and slipping on the elastic half plane. Plane strain condition is assumed for the present analysis. Several sample calculations are carried out to investigate the effect of the punch roundness, the shear load path, and the crack obliquity and closure on the failure. It is found that the present methods can be a useful tool for studying the physical failure of the of the contacting materials such as fretting wear and fretting fatigue cracking.

• 간호행정학회지
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• 제12권1호
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• pp.23-31
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• 2006

Purpose: The purpose of this study was to test the empowerment structural model based on Kanter's work empowerment theory. Method: A predictive, nonexperimental design was used in a sample of 279 nurses from 3 university affiliated hospitals. Data were collected with self-administered questionnaires and analyzed using mean, standard deviation, pearson correlation coefficient and path analysis. Results: The results showed that the overall fitness of the hypothethical model to the data was good(chi-square=.7751, df=4, p=.942, GFI=.999, AGFI=.996, RMSEA=.000). Both formal power and informal power directly influenced on nurses' perceived empowerment level and empowerment directly influenced on nurses' organizational commitment and indirectly influenced on nurses' intent to stay. Conclusion: The results imply that hospital and nurse managers should provide the empowering working condition for nurses to be stayed in hospitals.

• 한국CDE학회논문집
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• 제9권3호
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• pp.246-252
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• 2004

Presented in this Paper is a Micro Machining Service .(MIMS) based on the World Wide Web technologies. In order to ensure easy access to the service, the web browsers are used as the user interface. The pan geometry as an STL file is uploaded with process parameter for 3-axis CNC milling. Depending on the predefined user level, novice or expert, the user interface requires different parameters for process planning. An STL-based CAM resides in the server and automatically provides NC codes upon user's request. Tool-paths for scanning and pencil-cut, which are interference-free and precise, are created by the curve-based polyhedral machining method. A couple of sample parts were fabricated by a micro endmill with 127 fm diameter. From the tests, the parts fabricated by scanning followed by pencil-cut resulted in less error(within 2%) than the parts machined only by scanning tool-path.

• 대한가정학회지
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• 제35권5호
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• pp.195-211
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• 1997

This thesis is conducted a survey of consumer problems and dissatisfaction and their complaining behavior. It analyzes the complex and varied consumer problems and dissatisfactions, then minimizes them and motivates active response. Also, this thesis is intended to provide fundamental study that may be used for the formulation of consumer protection polices. For this purpose, questionary survey method was used and the sample was taken from 603 housewives lives in Seoul. The major results of the study are summarized as follows; 1) Quality of product was the most frequent problem among consumer problems and dissatisfaction. 2) The level of consumer complaining behavior was 50.69/100 which is a little above median point. Non-complaining behavior was the most frequent, and followed by private/public behavior, public behavior and private behavior. 3) Path analysis of the variables affecting complaining behavior showed total causal effect to be biggest for degree of information search. The experience of consumer problems and dissatisfaction of consumers caused positive effect though causal relation.

• 가정과삶의질연구
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• 제15권4호
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• pp.41-54
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• 1997

The purpose of this study is to analyze information search according to consumer's prior knowledge and degree of importance of products. Questionnare survey method was used in this research. The sample was taken from 548 university students in Seoul from 19th of June to 26th of June in 1997. Statistical methods used in this study were Frequency, Percentage, Regression and path Analysis. The major findings are summarized as follows; 1) The level of Consumer's prior knowledge showed somewhat middle. 2) Degree of importance of products showed in order of quality, A/S extension exchange price reliance of a manufacturing company a design etc. 3) Information search for the consumer's prior knowledge and importance showed high on the whole. The more prior knowledge consumer have the better they recognize for the importance of products. Therefore consumers are more likely to search information.

• 유통과학연구
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• 제19권8호
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• pp.57-67
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• 2021

Purpose: The purpose of this study was to explain the application of TPB and personal happiness on donation behavior and willingness to donate. Research design, data, and methodology: The population of this research is people in Indonesia who have a tendency in its culture to donate. The sample size used was 245 people with a purposive sampling method. The analysis technique used is Path Analysis using SEM-PLS. Result: The results show that the subjective norm had appositive and significant effect on attitude to donate; subjective norm has appositive and significant effect on the donation behavior. Personal happiness has a positive and significant effect on attitude to donate, and personal happiness also has a positive and significant effect on the donation behavior, and the donation behavior has a positive and significant effect on the attitude to donate. Conclusions: Being a responsible person to other people's conditions, as you see other people needing help, you will feel that you have the power to help them. you are often helping people in need, which concludes you are a compassionate person.