• 한국해양공학회지
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• 제33권5호
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• pp.447-453
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• 2019

Recently, environmental regulations have been strengthened for SOX, NOX, and CO2, which are ship exhaust gases. In addition, according to the 4th Industrial Revolution, research on autonomous ship technology has become active and interest in electric propulsion systems is increasing. This paper analyzes the power load characteristics of an electric propulsion ship, which is the basic technology for an autonomous ship, in terms of energy management. For the load analysis, data were collected for a 6,800 TEU container ship with a mechanical propulsion system, and the propulsion load was converted to an electric power load and clustered according to the characteristics using a SOM (Self-Organizing Map). As a result of the load analysis, it was confirmed that the load characteristics of the ship could be explained by the operation mode of the ship.

• 전기학회논문지
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• 제68권4호
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• pp.523-531
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• 2019

This paper deals with a wound-field synchronous machines(WFSM), with an electromagnet on its salient rotor, as an alternative to a permanent magnet in the rotor. We then examine the power performance characteristics, loss characteristics, V-curves and large short-circuit ratios for a large-scale synchronous generator, considering the leading and lagging operations, based on the finite-element method. We predict the performance of a 100MVA-class generator based on the operating range for a constant short-circuit ratio. At the last, We compared with the electromagnetic characteristics of three model according to number of slots.

• 한국식생활문화학회지
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• 제24권4호
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• pp.419-425
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• 2009

This study examined the effects of added amounts of shrimp powder on the physical and sensory properties of Jook for elderly foodservice operation. According to the amylograph data, the composite shrimp flour-wheat flour samples increased the gelatinization temperature, with increasing shrimp-flour content; moreover, initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and maximum viscosity were reduced. As the level of shrimp powder in samples increased, L-values decreased, and a-values and b-values increased. In addition, the Jook had higher viscosity and lower spreadability values as the amount of shrimp powder increased. Sensory characteristics, such as nutty taste, color, viscosity, and overall preference increased significantly with the addition of shrimp powder. In conclusion, to enhance the quality of Jook, a 3% addition of shrimp powder would be the most beneficial.

• 한국산학기술학회논문지
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• 제15권8호
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• pp.4809-4814
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• 2014

본 논문은 미세물분무 작동에 따른 화재 거동 및 제압 특성을 예측하는 데 있어서 FDS(Fire Dynamic Simulator)의 예측 성능을 평가하는 것을 목적으로 한다. 미세물분무의 초기액적분포 입력을 위해 Rosin-Rammler /log-normal 분포를 사용하였으며 모델 상수의 영향을 살펴보았다. 또한 미세물분무의 분사압력에 따른 화재 제압특성을 이전의 실험 결과와 비교함으로써 해석 모델을 검증하고 열유동 특성 및 가스 농도 변화를 분석하였다. 결과로부터 동일한 평균입경을 갖는 미세물분무도 액적분포의 특성에 따라 하부 위치에서의 액적 크기 및 속도에 큰 영향을 받고 있음을 확인할 수 있었다. 분무특성에 대한 실험결과와의 비교를 통해 적절한 초기입경분포를 결정하였으며 이를 이용하여 화재 시뮬레이션을 진행하였다. FDS 화재 시뮬레이션 결과는 온도의 변화 및 화재 제압 특성에 대하여 실험 결과와 좋은 일치를 보여주었다. 또한 미세물분무의 작동압력에 따른 열유동장 변화, 가스상 농도 변화의 예측에 있어 유용한 데이터를 제공할 수 있음을 확인하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(1)
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• pp.402-405
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• 2004

In this paper, the parallel operation of the IGBT and power stack for easy capacity enlargement series in the medium power capacity inverter system of the 660V voltage class is described. The parallel operation of the IGBT and power stack for 1.5MVA medium power inverter system's design is applied. The results of the parallel operation are described in this paper. The designed stack capacity for parallel operation is 800kVA class. For 1.5MVA inverter system, the 800kVA stack is applied with 2 parallel configurations. The 800kVA stack is designed with 3 parallel configurations of the IGBT Module. In this paper, the feasibility for easy capacity enlargement series in the medium power inverter by applying the parallel operation of the IGBT and power stack is verified. The experimental results show the good characteristics for the parallel operation of the IGBT and power stack.

• 한국주거학회논문집
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• 제25권3호
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• pp.131-143
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• 2014

The purpose of this study is to develop an operation manual of resident-driven community program by evaluating community program operation to realize a sustainable apartment complex and vitalize a community. To achieve this purpose, 8 community experts, who are in charge of 42 complexes of 7 autonomous districts among 25 districts in Seoul were interviewed from September 2013 to December 2013. Main results of the study are as follows. 1) Operational problems and improvements are deduced from evaluating operation process of community programs. It is found that smooth cooperation of main operators including a community vitalization association, a resident representative meeting and a control office is the most important. 2) Operation guideline for representative programs are suggested based on analysis of operational characteristics of 3 types of community programs; communication, recycling and environment management, according to program operation elements; material element, programming element, human element and finance element. 3) An operation manual of resident-oriented community program is presented after considering evaluation of operation processes and analysis of 3 types of operational elements of community programs.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1998년도 추계학술대회 및 정기총회
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• pp.12-16
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• 1998

The purpose of this paper is to develop a knowledge-based real-time decision support system to support decision makers for efficient berth operation of Inchon Port. In these days, the efficient berth operation has been many studied. The berth operation rules differ from port to port and the problem is highly dependent on natural, geographical and operational environment of port. In Inchon Port, the ship's entrance into port and departure from port is extremely affected by the status of dock and berth because of capacity restriction. First, we analyzed the specific characteristics of Inchon Port such as dock based on the data of 1997. And then, we construct the database of experts knowledge for berth utilization. Finally, we build the real-time decision support system for the efficient berth operation of Inchon Port to make the better berth allocation in case of not only regular scheduling but also dynamic scheduling such as delay in berth operation and exchange of ship between berths. The DSS is developed with graphic user interface(GUI) concept to help the user determining user interactive updating of the port status. Then this DSS will be provide decision maker with an efficient and fast way to berth allocation, and reduce wastes of time, space, and manpower in Inchon Port operation.

• 한국재료학회지
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• 제15권7호
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• pp.465-472
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• 2005

Preparation of copper film on PET substrate was carried out by cyclic operation of RF-magnetron­sputtering under continuous operation of ECR-CVD. The purpose of this study is aimed to an increase in deposition rate with keeping excellent adhesion between copper film and PET. In order to optimize the sputtering time under continuous ECR-CVD, cyclic operation concept is employed. By changing parameters of cyclic operation such as split of e and cycle time of A, the characteristics and thickness of the deposited copper film are controlled. As $\theta$ value increase, film thickness could confirm to increase and its surface resistivity value decreases. The highest adhesive strength appears at $\theta=0.33$ and cycle time of 30 min. The uniformity of copper film shows $5\%$ in our experimental range.

• 대한건축학회논문집:계획계
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• 제34권11호
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• pp.45-55
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• 2018

To reduce the energy consumption of HVAC system in buildings, thermally activated building system(TABS) has been applied to low energy building because of energy efficient performance and reduction of peak load. DOAS coupled with a parallel sensible cooling could be promising because TABS handles sensible heat load only. The purpose of this study was to evaluate the indoor thermal environment and cooling operation characteristic of TABS with dedicated outdoor air system(DOAS) in Korea climate. Indoor thermal environment and operation characteristic of TABS integrated with DOAS are investigated at different TABS operation schedules and climate conditions by simulation tests. The result shows that the DOAS is more suitable for hot and humid climates. And also it show that the potential of intermittent operation of TABS.

• 정보보호학회논문지
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• 제32권2호
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• pp.163-170
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• 2022

LEA는 2013년 국내에서 개발된 경량 블록암호이다. 본 논문에서는 블록 암호 운용 방식 중 CTR 운용 모드와 CTR 운용 모드를 활용하며 기밀성과 무결성을 제공하는 GCM 운용 모드의 구현을 진행한다. LEA-CTR의 최적화 구현은 CTR 운용 모드의 고정된 Nonce 값의 특성을 활용하여 사전 연산을 통한 연산 생략과 State 고정을 통해 State 간의 이동을 생략한 최적화 구현을 제안한다. 또한 제안 기법을 GCM 운용 모드에 적용 가능함을 보여주며, Galois Field(2¹²⁸) 곱셈 연산을 사용하는 GHASH 함수 구현을 통해 GCM 구현을 진행한다. 결과적으로 32-bit RISC-V상에서 제안하는 기법을 적용한 LEA-CTR의 경우 기존 연구 대비 2%의 성능 향상을 확인하였으며, 추후 다른 연구에서 성능 지표로 사용될 수 있도록 GCM 운용 모드의 성능을 제시한다.