• 한국신뢰성학회지:신뢰성응용연구
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• 제16권2호
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• pp.125-133
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• 2016

Purpose: The purpose of this study is to evaluate durability of platform safety step system in railway. Method: We performed finite element analysis & durability analysis of platform safety step system with VPD (Virtual Product Development) techniques and examined the durability standard & qualification life through the rig test during no failure test time in reliability qualification test. We continued to test 1 million cycles in KRS (Korea Railway Standard) for system's robust design performance. Result: FEM analysis results are 14.9MPa & 14.7MPa of pin-joint, pivot and durability analysis result is above 1 million cycles. we calculated theoretically no failure test time 855,000 cycles and through the 1 million cycles durability rig test in KRS standard we confirmed product quality. Conclusion: This platform safety step system was designed very safe in terms of a mechanical strength & durability.

• 기술혁신연구
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• 제19권1호
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• pp.145-175
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• 2011

본 연구의 목적은 중소기업과 대학 간의 공동기술개발 과제의 성과에 영향을 미치는 결정요인을 밝히는 것이다. 산학 간 공동연구에 대한 기존 문헌을 분석한 결과 과제성과에 미치는 주요 결정요인은 동반자특성, 관리특성, 관계특성으로 구분할 수 있었다. 성과변수로는 협력 결과에 대한 만족도, 협력 관계 지속성, 기술과 제품 활용을 선택하였는데 이는 분석대상 과제가 중소기업과 대학 간의 공동과제이며 소규모이고 단기임을 고려한 것이다. 연구에 필요한 자료는 2009년 중소기업청에서 주관한 산학연 공동기술개발사업에서 지원된 1,082개 과제를 모집단으로 하고 우편설문 조사를 통해 수집하였다. 회수된 설문지는 기업체 200개, 대학 305개였다. 이중에서 동일 과제에 대하여 기업과 대학이 함께 응답한 것은 55개였다. 자료 분석은 다중회귀분석 방법을 통해 중소기업과 대학의 설문응답을 각각 개별적으로 검증하였고, 또한 동일 과제에 대하여 함께 응답한 결과를 결합하여 분석하였다. 기업을 대상으로 한 분석 결과는 인력전문성, 시설과 장비, 커뮤니케이션, 전략적 중요도, 신뢰가 주요 영향 요인으로 나타났다. 대학 측의 성과에는 협력경험, 목표설정 명확성, 전략적 중요도, 신뢰, 커미트먼트가 영향요인으로 나타났다. 동일 과제에 대한 중소기업과 대학의 설문 결과를 결합하여 분석한 결과는 연구시설장비, 과제관리 충실성, 커미트먼트가 영향요인으로 나타났다.

• Physical Therapy Rehabilitation Science
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• 제11권4호
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• pp.414-420
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• 2022

Objective: In this study, the test-retest reliability and validity were presented to evaluate the usability of isokinetic rehabilitation equipment for the knee joint. Design: Cross-sectional design, reliability & validity study. Methods: Thirty healthy adults participated in the study. A CSMI dynamometer was used as a standardized measuring device to present the validity of the equipment. It was measured based on the dominant leg. The average peak torque value was selected as the measurement variable. After the measurement, a questionnaire was conducted on safety, satisfaction, and performance through the usability evaluation questionnaire. Results: The knee joint isokinetic rehabilitation equipment showed high reliability with Intraclass Correlations Coefficients (ICC) =0.883~0.956. In order to check the validity of the equipment, the 95% confidence interval of the mean difference limit was confirmed by the Bland & Altman plot. As a result, all three angular velocities showed a smaller confidence interval in the flexion than in extension. There were less than 10 plots that were not included in 2 Standard Deviation (SD) between all measurements. As a result of the usability evaluation questionnaire, the average of the safety domain(4.9±0.4), satisfaction domain(4.1±0.8), performance domain(4.3±0.8). Conclusions: If the product is improved by supplementing the items identified in the usability evaluation process, it is judged that it can be used as a useful device in various knee joint rehabilitation fields.

• 조명전기설비학회논문지
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• 제24권2호
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• pp.27-32
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• 2010

본 논문은 반도체 공정에 사용되는 고속 EFEM(Equipment Front End Module) 장치의 새로운 성능평가시스템을 제안한다. 다관절 로봇으로 구성된 EFEM은 실리콘 웨이퍼 또는 포토마스크를 클린 스토리지 캐리어와 각종 계측 및 테스팅 시스템 사이를 이동시키는 반도체 자동화의 핵심장치이다. 성능평가 시스템 개발을 위한 이론과 실험적인 연구가 수행되었고, 그 결과는 고속 EFEM 장치의 성능 평가시스템이 적합함을 입증한다. 특히, WTO/TBT(Technical Barhers to Trade) 협정 및 PL(Product Liability)법에 대처하는데 매우 효과적이다.

• 한국산학기술학회논문지
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• 제15권3호
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• pp.1390-1395
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• 2014

본 연구는 대학에서 새로이 개발한 멀티크림의 속성별 가치를 추정하여 신제품의 가격을 책정하고 제품 개발 방향을 설정하는 등 마케팅 전략 수립을 위한 기초자료를 제공하는데 그 목적이 있다. 분석 방법으로는 선택형 실험을 이용하였으며, 조건부 로짓 모형을 추정하여 브랜드, 용기 형태, 기능성, 가격 등 각 속성별 한계지불의사금액을 도출하였다. 연구 결과 소비자의 한계지불의사금액은 브랜드에 있어서는 대기업이 개당 21,754원, 중소기업이 11,033원, 대학은 16,178원으로 나타났으며, 기능성에 있어서 보습효과 강화는 7,476원, 주름개선효과 강화는 12,107원으로 추정되었다. 대학 브랜드가 중소기업 브랜드보다 선호도가 더 높은 것으로 나타났으므로, 대학과 중소기업이 협력하여 공동으로 사업을 추진할 경우 저가 브랜드 시장에서 경쟁력을 높일 수 있을 것이다. 또한 보습효과나 주름개선효과 등 기능성을 강화한 제품을 개발할 필요도 있다.

• Applied Microscopy
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• 제45권2호
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• pp.89-94
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• 2015

This article briefly reviews the results of recently reported research on high-temperature Pb-free solder alloys and the research trend for characterization of the interfacial reaction layer. To improve the product reliability of high-temperature Pb-free solder alloys, thorough research is necessary not only to enhance the alloy properties but also to characterize and understand the interfacial reaction occurring during and after the bonding process. Transmission electron microscopy analysis is expected to play an important role in the development of high-temperature solders by providing accurate and reliable data with a high spatial resolution and facilitating understanding of the interfacial reaction at the solder joint.

• 전기학회논문지P
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• 제63권4호
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• pp.361-367
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• 2014

This paper is related to a new solar power conditioner for a built-in step-up chopper function. In the first step-up chopper proposed solar PV power conditioner for mutually connected in series with the input voltage of the bypass diodes are respectively connected to the positive terminal should install the mutual boosting chopper diode connected in series with the boost chopper switching element between the two power supply and at the same time the first and the second was connected to a second diode and a resonance inductor and a snubber capacitor in series with each other. And the common connection point between the bypass diode and the step-up chopper and the step-up chopper diode common connection point of the switching elements of the input voltage was set to the boost inductor for storing energy. In addition, between the step-up chopper and the step-up chopper diode and a switching element of a joint connection point of the first auxiliary diode and the second common connection point of the auxiliary diode was provided, the resonance capacitor. Between the step-up chopper and the step-up chopper diode and a switching element of a joint connection point and the common connection point of the resonance inductor snubber capacitor and connecting the third secondary diode, between two power supply lines is characterized by configuring the DC link capacitor bus lines in parallel. Therefore, it is possible to suppress the switching loss through, DC link bus lines, as well as there could seek miniaturization and weight reduction of the power conditioner itself by using a common capacitor of the non-polar non-polar electrolytic capacitor having a capacitor, the service life of the circuit can be extended and it is possible to greatly reduce the loss can be greatly improve the reliability of the product and the operation of the product itself.

• Journal of Welding and Joining
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• 제27권2호
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• pp.63-68
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• 2009

Microminiature heat exchanger has been applied to the gas turbine in order to increase energy efficiency. During the production of microminiature heat exchanger, however, it is very difficult to weld tube to tubesheet. In this study, therefore, welding process of resistance ring projection was used, and weld tensile tests were performed. Sound weld joint was obtained as a result of applying resistance ring projection welding to microminiature heat exchanger to tubesheet. Cold weld occurred at under 1600A. Even though tensile strength was increased with increasing current, splash occurred and tensile strength decreased at 2000A due to the excessive current. Therefore it was determine that the optimal current is 1900A. As result of tensile tests based on ASME code for tube to tubesheet weldment, rupture position was weldment due to Fs(Fractured section) of nugget, which was smaller than tube thickness (t), and it was proven as a partial strength welding because of the average joint efficiency fr = 0.90.

• 수산경영론집
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• 제50권4호
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• pp.11-28
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• 2019

In this study, the Inter-Korea Fisheries Cooperation Project was divided into four categories: North Korea's Fisheries Infrastructure Development Project, Fisheries Cooperation Project, Human Exchange Project, and North Korea Fisheries Investment Project. First, North Korea's fisheries infrastructure development projects include North Korea's fisheries resource research project, it's fisheries resource development project, and joint enforcement on illegal operation of Chinese ships. Second, fisheries cooperation projects include the operation of the North-South common fish area in the West Sea, the fishing project in North Korea's East sea, and the import of North Korean seafood. Third, human exchange projects include training of aquaculture technicians in North Korea, technology transfer and training of fishing vessels, and boarding of North Korea's fisherman in Korean fishing vessels. Fourth, North Korea's fisheries investment projects include aquaculture facilities and aquaculture feed support, aquatic product processing facilities and technology transfer, and fishery equipment support. However, as international sanctions are maintained in the international community to North Korea, Inter-Korea Fisheries cooperation, however, should be promoted according to the level of easing of international sanctions as international sanctions are maintained in the international community to North Korea. First, North Korea's fisheries resource research project, North Korea's fisheries resource creation project, joint enforcement on illegal operation of Chinese ships, and operation of the common fish area in the West Sea can be promoted if international sanctions are maintained at present, promote North Korea's fisheries resource research project. Second, boarding of North Korean's fisherman in Korean fishing vessels, conducting the fishing project in North Korea's East sea, and importing North Korean seafood can be aided if commercial transactions are possible with North Korea. Third, South Korea will support aquaculture facilities and aquatic feed, fisheries processing facilities and technology transfer, fishery equipment support, training of fisheries and aquaculture technicians, fishery fishing technology transfer, and training of fisherman when a comprehensive economic cooperation project is possible with North Korea.

• 한국CDE학회논문집
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• 제17권1호
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• pp.35-44
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• 2012

Many automobile manufacturers are doing experiment on manufacturing environments by using an augmented reality technology. However, system layout and process simulation by using the virtual reality technology have been performed actively more than by using the augmented reality technology in practical use so far. Existing automobile assembly by using the augmented reality requires the precise calibrating work after setting the robot because the existing augmented reality system for the automobile assembly system configuration does not include the end tip deflection and the robot joints deflection due to the heavy weight of product and gripper. Because the robot is used mostly at the automobile assembly, the deflection problem of the robot joint and the product in the existing augmented reality system need to be improved. Moreover camera lens calibration has to be performed precisely to use augmented reality. In order to improve this problem, this paper introduces a method of the software based calibration to apply the augmented reality effectively to the automobile assembly system. On the other hand, the camera lens calibration module and the direct compensation module of the virtual object displacement for the augmented reality were designed and implemented. Furthermore, the developed automobile assembly system oriented AR-system was verified by the practical test.