• 한국정보통신학회논문지
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• 제16권9호
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• pp.2050-2055
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• 2012

센서 네트워크가 대중화되면서 서로 다른 요구사항을 가진 다수의 응용 프로그램이 개발되고 있다. 특히, 센서 데이터의 특성상 손실되거나 시간이 지난 데이터는 의미가 없기 때문에 신뢰성과 실시간성은 매우 중요한 요구사항이다. 이를 위하여 다양한 연구들이 진행되었지만 대부분의 연구는 오직 하나의 요구사항만이 고려되었다. 이러한 문제점을 해결하기 위하여 본 논문에서는 두 개의 요구사항을 만족시키는 방안을 제안한다. 제안 메커니즘에서는 신뢰성을 위하여 개발된 MintRoute 프로토콜을 확장하여 실시간 서비스인 (m,k)-firm 스트림을 지원하도록 몇몇 기능을 확장하였다. 또한, 시뮬레이션을 통하여 성능 검증 및 제안된 프로토콜이 두 서비스에 적합함을 증명하였다.

• 항공우주산업기술동향
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• 제6권2호
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• pp.31-39
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• 2008

본 논문에서는, 위성 영상자료 표준화에 대한 정의 및 표준화에 따른 일반 사용자들의 요구사항들을 설명한다. 위성을 개발하고 운영하더라도 일반 사용자가 사용하지 않는다면 그 위성은 무용지물일 수밖에 없다. 일반 사용자가 위성 영상자료를 원활하게 사용하기 위해서는 위성 영상자료에 대한 표준화가 이루어져야하고 한국항공우주연구원은 아리랑 위성의 개발 기관으로서 위성 영상자료의 표준화를 완수해야한다. 위성 영상 자료의 표준화를 위해서는 위성 개발 요구사항, 국제 영상자료 표준화, 일반 사용자 요구사항들을 반영해야 하고, 일반 사용자들에게 제공되는 영상자료도 표준 형식을 수용해야한다. 또한 위성 영상자료 품질을 확보하기 위한 검보정 작업이 필수적으로 수행되어야 한다. 한국항공우주연구원은 이미 운영 중인 아리랑 위성 2호를 포함하여 다목적 실용위성5호와 3호의 표준화를 위한 작업을 단계별로 수행 중이다.

• 시스템엔지니어링학술지
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• 제11권2호
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• pp.75-83
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• 2015

This paper describes modeling & simulation(M&S) model for dynamic analysis of helicopter rotor blades. Simulation model is developed using Dymola tool which implements the open source language - Modelica. Modelica is appropriate for developing multibody dynamic analysis model. To develop an M&S model efficiently, model based systems engineering(MBSE) is applied. Some diagrams such as requirement diagram, block definition diagram and sequence diagram etc. are drawn to capture the concept of M&S model. This activity is done utilizing the open source tool - Papyrus.

• 시스템엔지니어링학술지
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• 제5권2호
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• pp.17-26
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• 2009

This paper is about that case study of the Tube Transportation System that the new transportation system offering passenger and logistic service in a metropolis having plenty of the floating population or between medium-sized cities, and solving large issues like terrible traffic jams and environmental problems etc. in this region. Also it presented that elicitation results of performance parameter and the categorization system of it applying a systematic analysis methodology. By the medium of this paper, It showed that definition, case study, performance parameters, and the categorization system of parameters of a general tube transportation system before developing requirements of a specific tube transportation system. From now on, it will come in pretty handy in systems engineering of activities to establish a concept of a new tube transportation systems and develop requirements.

• 한국군사과학기술학회지
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• 제3권1호
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• pp.127-137
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• 2000

The term system architecting(SA) is widely used in systems engineering area, however the explicit meaning of the term varies considerably from person to person depending on his expertise and viewpoints. In this paper, we surveyed the range of variations in definitions and present the summary. Additionally, the definition of robust system architecting is suggested along with the associated system architecture guides that can be followed during an architecture development. This guide exposes various viewpoints of architecture such as art side, requirement specification, system view, principles, tools and environment.

• Neonatal Medicine
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• 제17권2호
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• pp.161-167
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• 2010

Acute kidney injury (AKI), formerly referred to as acute renal failure (ARF) is defined as the sudden impairment of kidney function (estimated from the glomerular filtration rate [GFR]) that results in the lack of excretion of waste products. More than 30 definitions of AKI exist in the literature, most of which are based on serum creatinine. Lack of a uniform and multidimensional AKI definition has led to failure to recognize significant renal injury, delays in treatment, and inability to generalize single-study results. The RIFLE criteria were developed to standardize the diagnosis of ARF and in the process the term AKI has been proposed to encompass the entire spectrum of the syndrome from minor changes in renal function to requirement for renal replacement therapy. Large prospective studies are needed to test definitions and to better understand risk factors, incidence, independent outcomes, and mechanisms that lead to poor short- and long-term outcomes. Early biomarkers of AKI need to be explored in critically ill neonates.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.996-999
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• 2008

Aspheric polymer lens fabrication using isothermal compression molding is presented in this paper. Due to increasing definition of an image sensor, higher precision is required by a lens which can be used as a part of an imageforming optical module. Injection molding is a factory standard method for a polymer optical lens. But achievable precision using injection molding has a formidable limitation due to the machining of complex mold structure and melting and cooling down a polymer melt under high pressure condition during forming process. To overcome the precision requirement and limitation using injection molding method, isothermal compression molding is applied to fabrication of a polymer optical lens. The fabrication condition is determined by numerical simulations of temperature distribution and given material properties. Under the found condition, the lens having a high precision can successfully be reproduced and does not show birefringence which results often in optical degradation.

• 대한수학회지
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• 제46권2호
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• pp.225-236
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• 2009

The equicontinuity and scattering properties of continuous semi-flows are studied on a compact metric space. The main results are obtained as follows: first, the complexity function defined by the spanning set is bounded if and only if the system is equicontinuous; secondly, if a continuous semi-flow is topologically weak mixing, then it is pointwise scattering; thirdly, several equivalent conditions for the time-one map of a continuous semi-flow to be scattering are presented; Finally, for a minimal continuous map it is shown that the "non-dense" requirement is unnecessary in the definition of scattering by using open covers.

• 대한안전경영과학회지
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• 제2권3호
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• pp.47-59
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• 2000

Producing what customers need with near mass production efficiency, or mass customization, has been a major trend in industry. Effective definition of customer requirements is a pre-requisite for realizing mass customization. The new method, called "Design by Customers", is proposed. The proposed method is an approach for companies to communicate to customers about what the company can offer, to find out customer needs, to assist customers in making choices and to negotiate for agreements. In this paper, the design and manufacturing capabilities in making company are represented in a Product Family Architecture. Adaptive Conjoint Analysis is then applied help customers assert their needs, defined variations from base product, visualize their options and assess alternatives. A power supplier of a electronic appliance is shown as an example to demonstrated the suggested method.ed method.

• 대한조선학회논문집
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• 제40권6호
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• pp.30-36
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• 2003

To improve survivability of damaged ship, assessment of stability and structural safety, and behavior analysis in wave is required. Prediction of sinking time, damage stability and structural strength considering progressive flooding and dynamic force in wave is very important. To do it, a geometric model which can be express damaged ship is prepared. This paper described the geometric modeler for survivability assessment of damaged ship. The modeler is developed based on 3-D geometric modeling kernel, ACIS. The hull form and compartment definition is available fundamentally. And requirement for modeler contains data generation and interface for hydrostatic calculation, behavior analysis, and longitudinal strength analysis and so on. To easy access modeling system by conventional user such as crew, user interface is developing.