• 한국해양공학회지
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• 제19권6호통권67호
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• pp.44-49
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• 2005

This paper investigates strength characteristics and stress-strain behaviors of unreinforced and reinforced lightweight soils. Lightweight soil, composed of dredged soil, cement, and air-foam, was reinforced by a waste fishing net, in order to increase its compressive strength. Test specimens were fabricated by various mixing conditions, such as cement content, initial water content, air content, and waste fishing net; then, unconfined compression tests were carried out on these specimens. From the test results, it was shown that reinforced lightweight soil had different behavior after failure, even though it had similar behavior as unreinforced lightweight soil before failure. The test results also showed that stress became constant after peak strength in reinforced lightweight soil, while the stress decreased continuously in unreinforced lightweight soil. It was observed that the strength was increased due to reinforcing effect by the waste fishing net for most cases, except high water content greater than $218\%$. In the case of high water content, a reinforcing effect is negligible, due to slip between waste fishing net and soil particles. In reinforced lightweight soil, secant modulus (E50) was increased, due to the inclusion of waste fishing net.

• Fisheries and Aquatic Sciences
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• 제3권2호
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• pp.156-162
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• 2000

Model experiments for a purse seine were carried out in order to measure the geometry of net shape and to estimate an enclosed volume by using 1177 scale model purse seine of 12.62m float line from an offshore mackerel purse seine. A model purse seine was set from a net box of shooting equipments and then pursing and hauling net by hauling equipment. The 3- D geometry shape of the purse seine net during hauling operation was measured by video image processing and tension of purse line by load cell. The 3-D geometry of the model purse seine during hauling operation could be represented with variables such as a ratio of shooting diameter or maximum net depth and a ratio of hauling operation time. Horizontal shapes of float line and lead line were varied from a circle after shooting to an ellipse with pursing and hauling. Projected lateral shape of purse line was observed and formulated as a shape of a water drop. The cross sectional shapes of curved net from two directions were varied such as sine function or polynomial curves. Therefore, enclosed volume of a purse seine in relation to fish school behaviour can be approximated using two main variables from relevant equations.

• 수산해양기술연구
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• 제41권3호
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• pp.227-233
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• 2005

In order to estimate the effective horse power(EHP) in towing net of a bottom trawl ship, the ship's resistance was calculated by using a series data of Yamagata and Wigley formula. Also the effective horse power for a ship(EHPs) was estimated versus the ship speed in sailing and the propulsive efficiency was calculated with the brake horse power and the effective horse power. Then the effective horse power for a ship and a trawl net were estimated in the application of the propulsive efficiency in towing net. The total effective horse power($EHP_T$) was average 187.6kW and the effective horse power for a 1.awl net($EHP_n$) was average 176.7kW at a smooth sea state in towing net. The ratio of $EHP_n$ to $EHP_T$ was about 94.0% and the value was higher slightly than was already informed at a smooth sea state. The power for keeping up a townet speed was required more about 20% of a maximum continuous power at a rather rough sea state than a smooth sea state. In the future, if the residual resistance is considered with a sea state, $EHP_n$ will be estimated more correctly Also the data of EHP estimated by this method will be used as the basic data to design a trawl net.

• 정보관리연구
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• 제29권2호
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• pp.1-17
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• 1998

분산되고 복잡한 정부 및 공공기관의 현행 기업지원체제의 어려움을 해소하기 위하여 창업, 자금, 기술, 입지, 판로, 무역투자 등 기업의 모든 경영활동에 관련된 정보를 체계적이고 종합적으로 구축, 제공하고 기업의 애로 및 민원을 신속히 발굴, 해소하기 위하여 정부 및 관련기관을 인터넷을 통해 상호 연계하는 종합기업서비스정보망의 구축과 이를 효율적으로 운영하기 위한 추진체계에 대하여 기술하였다.

• 한국철도학회논문집
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• 제13권6호
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• pp.570-576
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• 2010

본 논문에서 우리는 Petri Net을 사용하여 철도 선로를 모형화 하는 문제를 다루었다. Petri Net는 병행적, 비동기, 분산, 병렬, 비결정론, 확률론 등의 특성을 가진 정보처리시스템을 기술하고 시스템의 동적거동의 특성을 연구하기 위해 고안된 도식적, 수학적 모델링 도구이다. 검증 사례로서, 한국형 경량전철시험선 선로를 철도 시설물의 구성품(세그먼트, 궤도, 분기기, 승강장)으로 모델링하고, 대피선이 있는 단일 궤도에서 두 대의 열차가 동일한 방향에서 함께 진행하고 있거나 반대방향에서 동시에 진행을 하지만 충돌을 하지 않는다는 것을 보장하면서 설정된 진로를 이동하는 Peri Net 모형을 구현하였다.

• 임산에너지
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• 제21권1호
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• pp.25-31
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• 2002

경상북도 포항 지역에서 생육하는 평균 수령 37년생 상수리나무 천연림 생태계의 지상부 현존생물량 및 연순생산량을 분석하기 위해 2001년 8월에 총 10주의 표본목을 선정 벌목하였다. 수식 Wt=aD/sup b/ 를 사용하여 추정한 지상부 총 현존생물량은 115.47ton/ha으로 나타났다. 부위별 구성비는 수간목부 63.9%, 생지부 19.8%, 수피 14.0%, 그리고 잎 1.2%의 순으로 높았다. 총 연순생산량은 7.89ton/ha이었으며, 부위별 구성비는 현존생물량의 경우와는 다르게 수간목부, 수피, 생지부, 그리고 잎의 순 이었다.

• 한국CDE학회논문집
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• 제14권1호
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• pp.60-68
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• 2009

Because of the reduced product life-cycle, industries are making an effort to bring down the process planning time. In the traditional approach, we have to analyze established process planning, then design the time chart based on process information and drawing the formal time chart such as SOP(sequence of operation). Thereafter, it will be converted to PLC code that is a time consuming and redundant job. Similarly, Industrial automated process uses PLC Code to control the factory; however, control information and control code(PLC code) are difficult to understand. Hence, industries prefer writing new control code instead of using the existing one. It shows the lack of information reusability in the existing process planning. As a result, to reduce this redundancy and lack of reusability, we propose SOS-Net modeling method. Unlike past stabilized process planning that is rigid to any change; our proposed SOS-Net modeling method is more adaptable to the new changes. The SOS-Net model is easy to understand and easy to convert into PLC Code accordingly. Therefore, we can easily modify the control information and reuse it for new process planning. The proposed model plays an intermediary role between process planning and PLC code generation. It can reduce the process planning and implementation time as well as cost.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2002년도 춘계학술대회 논문집
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• pp.222-229
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• 2002

기존의 공급망이 디지털화되고 고객과 공급자간의 파트너쉽과 정보흐름에 있어서 고성능의 네트웍을 형성하는 새로운 개념의 네트 퀀을 가치넷 (value net)으로 정의한다. 이러한 가치넷은 고객이 그 중심에 위치하며 연관되는 제조 사이트와 공급자에 이르는 정보의 배분을 원활하게 해 준다. 본 연구의 목적은 복잡한 공급사슬의 흐름과정에서 발생하는 의사결정과정을 자동화하고 효율화하기 위해서 멀티에이전트를 이용한 프레임 을 설계하고 구매업무와 관련된 영역에 대하여 본 시스템을 구현해 보고자 하는 것이다. 에이전트의 지능적 판단을 위해서는 BDI (Belief, Desire, Intension) 모델을 이용하였다. 본 연구의 결과는 B2B 및 e-Business에서 에이전트를 이용한 조달 및 획득과 관련된 업무에 적용이 될 수 있다.무에 적용이 될 수 있다.

• ETRI Journal
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• 제37권5호
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• pp.856-866
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• 2015

A heterogeneous network (HetNet) is a network topology composed by deploying multiple HetNets under the coverage of macro cells (MCs). It can improve network throughput, extend cell coverage, and offload network traffic; for example, the network traffic of a 5G mobile communications network. A HetNet involves a mix of radio technologies and various cell types working together seamlessly. In a HetNet, coordination between MCs and small cells (SCs) has a positive impact on the performance of the networks contained within, and consequently on the overall user experience. Therefore, to improve user-perceived service quality, HetNets require high-efficiency network protocols and enhanced radio technologies. In this paper, we introduce a 5G HetNet comprised of MCs and both fixed and mobile SCs (mSCs). The featured mSCs can be mounted on a car, bus, or train and have different characteristics to fixed SCs (fSCs). In this paper, we address the technical challenges related to mSCs. In addition, we analyze the network performance under two HetNet scenarios-MCs and fSCs, and MCs and mSCs.

• 한국컴퓨터정보학회논문지
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• 제21권12호
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• pp.115-124
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• 2016

In this paper, a method to generate the extended model automatically on the critical elements in enterprise system based real time distributed architecture as well as the platform specific model(PSM) for Microsoft(MS) .NET platform is proposed. The key ideas of this method are real time distributed architecture should performed with satisfying strict constraints on life cycle of object and response time such as synchronization, transaction and so on, and .NET platform is able to implement functionalities including before mentioned by only specifying Attribute Code and maximizing advantages of MDA. In order to realize the ideas, functionalities which should be considered enterprise system development are specified and these are to be defined in Meta Model and extended UML profile. In addition, after definition of UML profile for .NET specification, by developing and applying these into plug-in of open source MDA tool, and extended models are generated automatically through this tool. Accordingly, by using proposed specification technology, the profile and tools easily and quickly reusable extended model can be generated even though low level of detailed information for functionalities which is considered in .NET platform and real time distributed architecture. In addition, because proposed profile is MOF which is basis of standard extended and applied, UML and MDA tools which observed MOF is reusable.