• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.395-396
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• 2006

This paper presents the optimal design of Robot-Arm part use Design of Experiment(DOE). The DOE(Design of Experiment)was conducted to find out main effect factors for design of Robot-Arm part. In this design of Robot-Arm, 5 control factors include numbers of 4 level are selected and we make out L16 orthogonal array. Using this orthogonal array, find out optimal value and main effect factors of object function for design of Robot-Arm part by 16 times of test. We evidence this optimal value by using CATIA V5 Analysis.

• 한국자동차공학회논문집
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• 제3권2호
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• pp.77-85
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• 1995

Among mechanical friction losses in an engine, the piston assembly and cylinder components accounts for the majority of the losses. The movable bore technique has been developed and turned out to be the most reliable technique in measuring the instantaneous friction of piston assembly. The weakness of this system, however, was the presence of the protruded top of movable bore necessary for pressure balancing. Because of the protruded part the piston could not be taken out without disassembling the crankshaft. Present study was carried out with a system of removable top of the movable bore so that it was possible to make frequent piston removals. The effects from engine speed, oil viscosity, engine load and elastic contact pressure of piston rings on the frictional characteristics have been evaluated with the improved equipment. Also, frictions of each member of piston assembly were measured.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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• pp.443-448
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• 1998

With using artificial neural networks (ANNs), an analytical study related to the heated length effect on critical heat flux(CHF) has been carried out to make an improvement of the CHF prediction accuracy based on local condition correlations or table. It has been carried out to suggest a feasible criterion of the threshold length-to-diameter (L/D) value in which heated length could affect CHF. And within the criterion, a L/D correction factor has been developed through conventional regression. In order to validate the developed L/D correction factor, CHF experiment for various heated lengths have been carried out under low and intermediate pressure conditions. The developed threshold L/D correlation provides a new feasible criterion of L/D threshold value. The developed correction factor gives a reasonable accuracy fur the original database, showing the error of -2.18% for average and 27.75% for RMS, and promising results for new experimental data.

• Journal of Advanced Marine Engineering and Technology
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• 제26권6호
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• pp.661-669
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• 2002

Rapid tooling technique enables us to make dies and molds that produce prototype parts with the correct material at a substantially reduced cost and time. In this study, experiments on selective laser sintering of tungsten carbide-cobalt mixture were carried out to find optimal sintering conditions that will be applied to rapid metal tooling. The experiments were carried out within an air, an argon and a nitrogen atmosphere. Coupons of single layer were sintered at various laser powers, scanning speeds and scan spacings. Very severe oxidation took place within an air atmosphere. The oxidation is reduced significantly within an argon and a nitrogen atmosphere. The thickness of the sintered coupons is increased as the energy density, the laser energy Per unit scanned area, is increased. Several multi-layer sintering experiments were also carried out.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1465-1469
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• 2003

In general satellite verification process, the AOCS (Attitude & Orbit Control Subsystem) should be verified through several kinds of verification test which can be divided into two major category like FBT (Fixed Bed Test) and polarity test. And each test performed in different levels such as ETB (Electrical Test Bed) and satellite level. The test method of FBT is to simulate satellite dynamics with sensors and actuators supported by necessary environmental models in ETB level. The VDS (Vehicle Dynamic Simulator) try to make the real situation as possible as the on-board processor will undergo after launch. The purpose of FBT test is to verify that attitude control logic function and hardware interface is designed as expected with closed loop simulation. The VDS is one of major equipments for performing FBT and consists of software and hardware parts. The VDS operates in VME environments with target board, several commercial boards and custom boards based on the VxWorks real time operating system. In order to make time synchronization between VDS and satellite on-board processor, high reliable semaphore was implemented to make synchronization with the interrupt signal from on-board processor. In this paper, the real-time operating environment used on VDS equipment is introduced, and the hardware and software configurations of VDS summarized in the systematic point of view. Also, we try to figure out the operational concept of VDS and AOCS verification test method with close-loop simulation.

• 소성∙가공
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• 제18권2호
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• pp.135-143
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• 2009

In the casting industry field, a lot of researches have been carried out to maximize soundness and productivity and improve quality of mass produced products. The researches on the optimum mould design by using computer simulation have achieved a lot of accomplishments in the die-casting process especially. Their results are utilized to mass-produce sound products in their field. But there are some difficulties to use the simulation in order to make the design of product and mould. In general, repetitive calculations of computer simulation require much analyzing time in order to make sound design of them. Another difficulty is that only expertise technicians can analyze results of the simulation. In order to solve such a problem, we are building mould design optimization system which consists of knowledge-based module, simulation, optimization module and interactive modeler(it is based on the commercial modeler). By using and interacting between these modules of that system, we can easily make an optimum design of mould and construct the database. This study introduce the general process of the system and connection method between the modules is mentioned above and some examples to apply it to real product.

• 에너지공학
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• 제19권2호
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• pp.57-61
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• 2010

국내 에너지자원 자급률을 높이기 위해서는 적극적인 해외유전개발투자를 통한 생산 유 가스전 매입, M&A, 기존 생산광구 증산 등을 추진해야할 것이다. 이를 위해서는 생산 유 가스전 평가, 설계, 운영 등과 관련된 핵심 전략 기술에 대한 확보가 필수적이라고 할 수 있다. 향후 지속적인 연구개발 지원을 통한 생산광구평가와 생산 최적 설계.운영 기술 축적으로 해외 매입 가능한 유 가스전의 증가와 기존 유 가스전의 생산량 증대, 효율적인 광구 운영을 통한 석유 가스 자주개발률 제고를 기대할 수 있을 것이다.

• 한국농공학회지
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• 제12권2호
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• pp.1965-1970
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• 1970

The experiment was carried out in order to improve the leakage stopping work in the irrigation canal founding on the porous soil. But the experiment had many problems to be studied more owing to the insufficient time and facilities. The results obtained are summarized as follows; 1. Polyethylene film is estimated not to make strength decrease owing to buring in the subsoil, but to make owing to the sunlight. 2. Coated nylon shows the tendency to deteriorate strength when it is buried in the earth or exposed to the sun for long time, but leakage is all but impermeability generally. 3. Leakage loss rates for one hour show some differences in the canal to be full with water in accordance with operating methods, that is, the clay lining section is 12.6%, the coated nylon lining section is 1.7%, the polyethylene film lining section is 1.3%, respectively. 4. Leakage quantities per wetted perimeter unit area show $3.556cc/cm^2/hr$. in the clay lining section, $1.574cc/cm^2/hr$. in the coated nylon section, $0.695cc/cm^2/hr$. in the polyethylene film lining section, respectively. 5. When the construction fund make the clay lining section as a standard, the polyethylene film section is 92.1%, the coated nylon section is 174.2%, respectively. But, the unit cost of execution may be low when the polyethylene film and the coated nylon will enable to mass-produce for the purpose of execution.

• 성인간호학회지
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• 제16권3호
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• pp.366-377
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• 2004

Purpose: This study is a descriptive research study to develop the Nurse's Humor Questionnaire, and then analyze humor's appreciation and use by Korean nurses. Method: The three stages used to develop the questionnaire were to make a conceptual framework, make an open questionnaire through the 2nd preliminary inquiry, and make a structured questionnaire based on collected statements through the developed open questionnaire. The subjects that carried out completely a structured questionnaire were 337 nurses. Result: 1) The final developed questionnaire consists of 6 domains and 67 items. The reliability of 'When feeling humor's expression'(${\alpha}=0.7079$), 'The barrier factors of humor's use'(${\alpha}=0.7895$), and 'Humor's values' (${\alpha}=0.8336$) was high. 2) The results related to Humor's values of nurses that showed significant differences were as follow: (1) age, marital status, and current position (2) a negative correlation between stress and humor's values (3) humor's sources: daily life and conversation (4) frequency of used humor (5) types of used humor: word humor, imitation, adequate situation and technical terms, and (6) when using humor's expression: tense atmosphere, awkward atmosphere and adequate situation. Conclusion: The developed tool can be used for understanding nurse's humor. This will help to develop the humor program as a nursing intervention for health promotion.

• 한국농촌생활과학회지
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• 제5권2호
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• pp.199-205
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• 1994

In the process of industralization, Korea rural aged have played great role. By investing, educating, and supporting their brothers and children, rural aged transferred their economic surplus to non agricultural fields and urban areas. But they did not prepare for their old age. So in every agricultural policy implementation, special concern should be taken to rural aged. The rural home extension should be the major institution for the rural aged. This paper was carried out to find the direction and the policy task of rural guidance project for rural aged. This paper suggested the needs of support for the aged in family, economic status and income, and leisure. To support the aged in family, the rural home extension should teach them how to make good relationship between Mother-in-law and daughter in law and special support to families which composed of only rural aged(no children). The rural home extension program should provide special policy for job opportunity creation for the rural aged. The rural home extension should also make educational programs for useful utilization of leisure time of rural aged. The rural home extension should make major roles in rural aged related policy. So rural home extension workers are well trained in gerontology and more related information should be provided.