• Journal of Electrical Engineering and Technology
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• 제9권2호
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• pp.733-738
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• 2014

We propose a new approach called as a peak time approach for faster detection of step initiation for the lower limb exoskeleton. As faster detection of step initiation is an important criterion in evaluating the lower limb exoskeleton, many studies have investigated approaches to detect step initiation faster, including using electromyography, the center of pressure, the heel-off time and the toe-off time. In this study, we will utilize vertical ground reaction force events to detect step initiation, and compare our approach with prior approaches. Additionally, we will predict the first step's heel strike time with vertical ground reaction force events from multiple regression equations to support our approach. The lower limb exoskeleton should assist the operator's movement much faster and more reliably with our approach.

• 정보관리연구
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• 제28권1호
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• pp.34-61
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• 1997

본고에서는 국내 대학도서관과 국외 프로젝트 등 전자문헌제공의 현황분석을 기반으로, 대학도서관이 수행해야 할 전자문헌제공의 단계별 모형을 제시하고자 한다. 모형의 단계는 이용자의 신청단계, 전자문헌 구축단계, 전자문헌 전송단계로 구성되며, 대학도서관은 전자문헌제공을 각 단계별로 실시하여 최신 정보를 요구하는 이용자의 정보 욕구를 충족시킬 수 있다.

• 소성∙가공
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• 제12권5호
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• pp.449-456
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• 2003

Multi-step induction heating process was applied to the powder compact melting technique as a new heating process to achieve pinpoint accuracy, faster cycle time, repeatability, non-contact and energy-efficient heat in a minimal amount of time. The objective of this study is the establishment of the input data diagram of multi step induction heating process for automation of the fabrication process of 6061 Al foams with desired density. At first, proper induction coil was designed to obtain a uniform temperature distribution over the entire cross sectional area of specimen. By using this coil, foaming experiments were performed to investigate the multi-step induction heating conditions such as capacity, temperature and time conditions of each heating and holding step. On the basis of the obtained multi-step induction heating conditions, relationship between final heating temperature and fraction of porosity was investigated.

• 대한기계학회논문집
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• 제12권5호
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• pp.984-991
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• 1988

본 연구에서는 유압관로에서 액주분리를 수반하는 유체 과도현상의 압력파형 에 때때로 관측되는 2단적 압력상승현상의 발생기구를 실험 및 이론적인 추론, 특성곡 선법을 사용한 수치해석을 통하여 명확히 구명함을 목적으로 한다.

• Bulletin of the Korean Chemical Society
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• 제21권4호
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• pp.419-424
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• 2000

In this study we have investigated the determination of proper time step in molecular dynamics simulation.Since the molecular dynamics is mathematically related to nonlinear dynamics, the analysis of eigenvalues isused to explain the relationship between the time step and dynamics. The tracings of H2 and CO2 molecular dynamics simulation agrees very well with the analytical solutions. For H2, the time step less than 1.823 fs pro-vides stable dynamics. ForCO2, 3.808 fs might be the maximum time step for proper molecular dynamics. Al-though this results were derived for most simple cases of hydrogen and carbon dioxide, we could quantitatively explain why improperly large time step destroyed the molecular dynamics. From this study we could set the guide line of the proper time step for stable dynamics simulation in molecular modeling software.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 1998년도 학술대회지 vol.1
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• pp.57-68
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• 1998

ㆍ STEP is an International Standard (ISO 10303) - that defines the methodology to create computer interpretable product data models. ㆍ STEP Implementation - allows exchange and sharing of product data while retaining semantics throughout the product life cycle. ' STEP is in deployment - PDM data exchange at Boeing and others - Geometry data exchange at GM and others ㆍ The STEP community overcomes obstacles - “They will never finish the standard” (done 1994) - “They will never be able to transfer solids” (done 1995) - “They will never make solids transfer reliable” (done 1997) - “They will never implement all those Application Protocols”(TBD)(omitted)

• 전력전자학회:학술대회논문집
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• 전력전자학회 1997년도 전력전자학술대회 논문집
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• pp.318-321
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• 1997

This paper is about improving characteristic of plant by using micro-step driver method in 5 phase step motor for satisfying the condition of low oscillation and high accuracy in soldering machine. We choose open loop control method for minimizing hardware system and use one chip microprocessor, power MOSFET nd some device to realize accurate micro-step driver system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.484-485
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• 2006

The one step type pole and two step type pole are used in KEPCO's distribution system. The neutral current may occurs in three-phase four-wire distribution system due to unbalanced load. This paper presents neutral current both one step type pole and two step type pole in distribution system.

• 대한전자공학회논문지
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• 제27권12호
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• pp.1810-1816
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• 1990

Step discontinuities of microstrip lines are analyzed using the mode-matching technique based on the well-known waveguide model. Including higher-order modes, the generalized scattering matrices are obtained. Asymmetrical step discontinuities as well as symmetrical step discontinuities are analyzed. The resonance characteristics of microstrip patches are calculated by cascading two microstrip step discontinuities through a uniform microstrip line. Experimental results agree well with theroretical ones.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.395-399
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• 1997

An international standard for the product model data, STEP, and a standard for the distributed object technology. CORBA, will play a very important role in the future manufacturing environment. These two technologies provide background for the sharing of product data and the integration of applications on the network. This paper describes a prototype CAD/CAE enviroment that is integrated on the network by STEP and CORBA. Several application servers and client software were developed to verify the proposed concept.