• Transactions of Materials Processing
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• v.20 no.5
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• pp.357-361
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• 2011

A beryllium copper alloy(C1720) sheet was stretch-drawn using different processes. A hemispherical punch was first used and the forming behavior was examined. Then, cylindrical cups with a hemispherical head were produced by either one-step drawing or two-step forming(sequential stretch forming-drawing). The one-step drawing showed the better formability than two-step forming. However, the two-step forming was the superior process in terms of attaining shape accuracy.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.250-253
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• 2001

This paper describes the effect of step bilge on motion characteristics of FPSO. The purpose of the present study is to investigate motion responses of FPSO with two types of step bilge. Model test result shows that the performance of the bottom type step bilge, that is designed to avoid collision, is as good as that of the side type step bilge.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2005.11a
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• pp.317-320
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• 2005

기존의 블라인드 등화(blind equalization) 알고리즘의 step-size는 임의의 값을 알고리즘에 적용하여 수렴속도와 정상 상태의 특성을 고려하여 최적한 step-size를 결정하였다. step-size를 크게 하면 수렴속도는 빠른 반면에 정상 상태에서 에러가 크고, step-size를 작게 하면 수렴속도는 느린 반면에 정상 상태에서 에러가 작아진다. 그렇기 때문에 수렴속도와 정상 상태를 고려해서 step-size를 결정해야 되고, 특별하게 정해지는 기준이 없기 때문에 연구자의 판단에 의해서 다르게 선택된다. 본 논문에서는 등화기 출력의 잔류 심벌간 간섭에 따라 step-size를 가변함으로서 수렴속도 및 정상 상태 성능을 개선한 가변 step-size를 갖는 블라인드 등화 알고리즘을 제안한다.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.10
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• pp.132-140
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• 2000

In conventional drilling, burr geometry can be changed according to the variation of drill geometry like point angle, rake angle. Step drilling is proposed to minimize the burr formation in drilling operation. The burr formed in first cutting can be removed in second cutting by the edge in step. The burr formed in second cutting by the edge in step can be minimized according to the change of geometry like, step angle and depth. The mechanism in step drilling is analyzed. Some step drills are applied to drilling the input shaft which is used for vehicle steering. To measure the burr formed in drilling, laser and height gage are used.

• Mycobiology
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• v.39 no.1
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• pp.67-69
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• 2011

A cell-free extract of Saccharomyces cerevisiae containing the angiotensin I-converting enzyme (ACE) inhibitory peptide was treated in a successive simulated gastric-intestinal bioreactor (step 1: amylase digestion, step 2: gastric fluid digestion, step 3: intestinal fluid digestion) to illustrate the absorption pattern of antihypertensive ACE inhibitory peptide, and the ACE inhibitory activities of each step were determined. Total ACE inhibitory activities of step 1, step 2, and step 3 were 55.96%, 80.09%, and 76.77%, respectively. The peptide sequence of each steps was analyzed by MS/MS spectrophotometry. Eleven kinds of representative peptide sequences were conserved in each step, and representative new peptides including RLPTESVPEPK were identified in step 3.

• Journal of Urban Science
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• v.9 no.1
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• pp.61-68
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• 2020

Steps are very common features in our living environment. Unfortunately, the occurrence of accidents on steps is thus inevitable. A failed visibility to recognize a step remains the most common attribute in these accidents. In this research, sensory scales of step visibility were created in order to examine the effects of two factors on step visibility in sensory testing methods; observation height from floor and eye condition while viewing a step from the descending direction. Results of sensory tests revealed strong influence of eye condition on step visibility. Influence of visual characteristics of each step was also examined and clarified.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.13
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• pp.283-302
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• 2000

The firms aim to acquire services and costs advantage from logistics outsourcing strategy. But it is very important to select optimum service provider. A checklist of the criteria for the evaluation of service providers follows : service quality, low cost, logistics information system, service network, financial stability, investments in plant and equipment, management attitude and lookout for the future strategic fit, cultural and psychological barriers etc. Also, a 8-step implement of logistics outsourcing strategy will be of help for maximizing benefits of logistics outsourcing. It follows : 1-step : logistics environment analysis, 2-step : check service provider availability, 3-step : logistics outsourcing determinant analysis, 4-step : select of optimum service provider, 5-step : contract with optimum service provider, 6-step : identify of remaining barriers, 7-step : performance of logistics outsourcing, 8-step : evaluation.

• Korean Journal of Computational Design and Engineering
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• v.12 no.5
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• pp.366-375
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• 2007

Although the STEP modularization is the major development methodology for STEP Application Protocol, there have been few studies on the STEP Modularization in Korea. The necessity of STEP Modularization research has been raised continuously. In addition, the importance became larger and larger because most of newly developing APs, including AP241, are developed using modularization approach. The object of this study is to investigate the basic structure and contents of AEC facilities related Application Modules using STEP Modularization. This study examines 1) the technical analysis regarding STEP Modularization, 2) application modules development regarding civil engineering elements of AP241; Aec_faciliteis_classification", "Aec_civil_item", and "Aec_civil_componet", 3) the developed application modules verification, and 4) the implementation methodology suggestion for application modules and modular AP.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.5
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• pp.179-184
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• 2006

In a power system, an out-of-step condition causes a variety of risk such as serious damage to system elements, tripping of loads and generators, mal-operation of relays, etc. Therefore, it is very important to detect the out-of- step condition and take a proper measure. This paper presents a study on implementation of out-of-step detection algorithm using VHDL(Very high speed Hardware Description Language). The structure of out-of-step detection algorithm is analyzed for development of out-of-step detection relay on the FPGA(Field Programmable Gate Array). The out-of-step algorithm is separated to 4 parts: DFT IP, complex power calculation IP, out-of-step detection IP, control unit. Each parts are developed and simulated by using VHDL.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1342-1349
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• 2006

오늘날의 제품개발환경은 분산환경에 존재하는 다양한 역량을 가진 참여자들의 협업을 요구하고 있으며, 협업은 참여자들이 필요로 하는 제품개발관련 정보들의 실시간 교환을 지원할 수 있도록 제품정보 간 상호운용성 확보를 기반으로 한다. STEP으로 알려진 ISO 10303은 제품개발의 전체적인 라이프사이클에서 필요한 제품정보의 표현과 공유 및 교환을 위한 대표적인 표준이다. 하지만 STEP을 이용하기 위해서는 각 도메인이 표준인 STEP 모델에 기반하여 제품정보를 모델링 하여야 한다. 그러나 대부분의 도메인은 자신의 목적에 따라 특화된 모델을 정의하고 사용하기 때문에 도메인에 특화된 형태의 제품정보모델을 STEP 모델로 변환할 수 있는 추가적인 메커니즘이 필요하다. 즉, STEP은 참조모델보다는 모든 도메인에서 제품정보모델링을 위해 사용가능한 표준의 정의에 초점을 맞춘다. 그러므로 참조모델로서의 STEP을 기반으로 다양한 도메인 특화된 제품정보모델 간 상호운용성 확보를 지원하기 위하여 본 논문에서는 STEP 제품정보모델의 시맨틱스를 체계적으로 정의할 수 있도록 온톨로지 구축을 통한 컨셉추얼 모델링을 수행한다. 컨셉추얼 모델링은 STEP 모델에 정확하고 완전한 의미를 부여하여, 다양한 도메인 특화된 모델 사이의 상호운용성 확보를 지원하고 참조모델로서 STEP의 능력을 확장한다.