• KIEAE Journal
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• v.13 no.1
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• pp.29-37
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• 2013

This study intended to introduce the method of designing an eco-friendly building based on BIM(Building Information Modeling) and BIM-based application. The proposed application aimed to generate the environmental performance of the designed alternative automatically in real-time manner in the process of architectural design. We focused on the feasibility of BIM-based eco-friendly design process and the applicability of the developed application for the architectural design practice. In this manner, in the end of paper, we proposed the so-call EcoBIM which is the performance evaluation module for the designed alternative using BIM in the real-time manner and the new design process with it. EcoBIM generate the coefficient of overall heat transmission of wall, roof and slab of the designed alternative with their physical characteristics such as thickness, thermal resistance and so on.

• Proceedings of the KIEE Conference
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• 2002.04a
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• pp.204-206
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• 2002

계통연계 풍력발전시스템의 특성을 고찰하기 위해서는 블레이드, wind turbine, 정류기, 인버터 등의 풍력발전시스템의 각 구성요소의 모델링과 적절한 제어 알고리즘에 대한 모의가 요구된다. 본 연구에서는 동기발전기를 풍력발전기로 사용하고 있는 계통연계형 풍력발전시스템의 출력 및 동특성을 모의하기 위한 전류제어형 전압원인버터의 PSCAD/EMTDC 모듈을 제시한다. 풍속의 가변특성에 의해 동기발전기에 들어오는 입력은 변하게 되고, 동기발전기가 동기주파수를 유지할 수 있도록 인버터에서는 이러한 입력과 동일한 출력을 낼 수 있어야 하며, 동시에 계통에서 허용하는 일정 전압과 계통주파수와 동일한 주파수를 갖는 출력을 공급해야 한다. 본 논문에서는 이를 위해 동기발전기의 주파수를 제어하는 전류제어형 전압원인버터 모듈을 소개한다. 모의를 통해 결과를 검증한다.

• Tribology and Lubricants
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• v.33 no.1
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• pp.31-35
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• 2017

Recently, international attention has been focused on the development of non-traditional energy resources such as shale gas and oil sands, due to the steep increase in the demand for natural resources. The materials incorporated in an oil gas plant module experience extreme environments, and are prone to various problem such as fracture, corrosion and abrasion due to low-temperature brittleness. In order to improve the plant life, it is necessary to perform characteristics study and performance evaluation of the materials. In particular, this paper explains the main set of materials which are most frequently used in oil sands plant project. In order to investigate wear characteristics, the authors carried out abrasive wear tests of TP 316, stainless steel and SS 400, structural rolled steel. For the analysis of the abrasive wear resistance of an oil sands plant, the authors carried out the test according to ASTM G 105 "Standard Test Method for Conducting Wet Sand/Rubber Wheel Abrasion Test" standard guidelines. The authors have derived the results from the data associated with the loss of mass with respect to wear rate. During the test, for a given wear length for 10,000 revolutions, the rotational speed and applied force of the rubber wheel were varied.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.6
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• pp.635-646
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• 2007

Human Powered Vessel Festival (HPVF) hosted by the College of Engineering of Chungnam National University, the Society of Naval Architects of Korea and the Korea Ocean Research & Development Institute has been held annually in Daejon since 1999. Solar boat powered by solar energy appeared for the first time in 2006, and it is expected that more new teams will enter this competition in the coming years. In this paper it is described that design procedures and manufacture processes of the solar boat named EPISODE. Firstly, It is aimed to understand compositions of the electric system and their performance properties and to show the design procedures using commercial design packages line WAVIS, CATIA, HCAD etc. Through the trial test, we confirmed ship speed, maneuverability, durability and operation condition of the electric system and found some problems. We plans to make reported problems go away and install hydrofoils for more improved speed performance.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.370-375
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• 2011

BIPV시스템 분야는 다른 PV 적용 기술 분야에 비해 빠르게 성장하고 있으나 소형 건축물 위주로 적용되었으며, 초고층 건축물과 같이 수직적으로 높은 건축물의 외부환경조건에 대응하기 위한 BIPV의 적용 방안은 현재까지 연구되어지지 않았다. 국내의 경우 선진국에 비해 초고층 건축물에 대한 BIPV시스템 적용기술은 아직 초기 연구단계에 불과하다. 초고층 건축물의 고유의 특징을 고려하여 초고층 건축물 파사드에 입사하는 일사량의 분포가 균일하지 않을 것이라고 예측하고 실측을 진행하였으며, 실측 결과의 분석을 통하여 초고층 건축물에서의 BIPV시스템 최적 설계방안을 제시하였다. 결론적으로 본 연구에서는 초고층 건축물의 외벽에 입사하는 일사량을 고려한 Unit형 BIPV설계 방안을 제시하였으며, 특히, 측정된 일사량 데이터를 활용하여 초고층 건축물에 적합한 인버터의 선정의 대안을 제시하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.174.2-174.2
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• 2016

도금은 크게 전해 도금과 무전해 도금으로 나눌 수 있다. 전기적 에너지를 사용하여 이온 상태의 금속을 환원시켜 석출함으로써 도금을 진행하는 전해 도금과는 달리 무전해 도금은 도금액 내의 환원제에 의해 금속 이온을 환원시켜 도금을 진행한다. 무전해 도금법은 전해 도금에 비해 전류 인가 장비가 필요하지 않아 도금 공정이 간단하고, 피도금체에 따른 인가 전류, 전압, 금속의 환원 전위 등을 계산하지 않아도 되기 때문에 전문적인 지식이 없어도 도금을 할 수 있다. 하지만 무전해 도금은 도금이 진행 될수록 도금액 내 금속 이온, 환원제의 농도 등이 수시로 변화하기 때문에 도금액의 조성을 파악하여 원하는 두께의 도금층을 형성하는 방법에 대한 연구가 필요하다. 본 연구에서는 무전해 도금액 내 환원제, 도금액 온도, 도금 시간을 변경하여 Ni 무전해 도금을 형성 하였고 그 특성을 평가하였다. 도금은 각각 플라스틱, RF module 유리 등 다양한 기판에 진행 하였으며, 도금 후 밀착성, 도금 두께 및 microstructure를 분석하였다. 도금 후 밀착성을 분석하기 위해 열처리 후 박리정도를 테스트를 하였고, 도금 두께 및 microstructure를 분석하기 위해 field emission scanning electron microscope (FE-SEM), energy-dispersive spectroscopy (EDS)를 사용하였다. 실험 결과, 두께 $3{\sim}5{\mu}m$ 급의 균일한 도금층이 형성된 것을 확인하였으며, $260^{\circ}C$에서 3회 열처리 후 박리성 평가 결과, 결함 없는 양호한 표면을 나타내었다.

• Journal of information and communication convergence engineering
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• v.11 no.4
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• pp.247-252
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• 2013

An intelligent light emitting diode (LED) dimming system is designed and implemented for energy-saving lighting systems. An LED light bulb is powered by an LED driver controlled by a microcontroller using pulse width modulation (PWM) signals. By changing the duty cycle of the PWM signals, the LED driver generates a driving current of up to 1,000 mA. The current consumption by the LED light bulb exhibits a very linear characteristic that indicates that the level of LED dimming can be finely tuned. Multiple sensors-lighting intensity and ultrasonic range sensors-are combined with the LED dimming system to realize an automatically controllable LED lighting system. The light intensity sensor is capable of sensing ambient light. The ultrasonic range sensor can detect objects from 0.15 to 5.6 m at a resolution of 0.0254 m. The collected information by the light intensity and ultrasonic range sensors is processed by the microcontroller that in turn automatically controls the brightness of the LED light bulb. The algorithm of the software for the LED dimming system is also described.

• The Transactions of the Korea Information Processing Society
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• v.2 no.3
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• pp.314-323
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• 1995

Recently, as users' understanding about software is raised, software developers devoted all their energy to satisfy users' needs. Accordingly, software is getting increase in volume and becoming complicated. As account of it, development and maintenance costs of software have been increased, and a large number of developers were projected in maintenance and development of new software. Software with good maintenability has a function in a module and is easy to read and simple. In this paper, for effective management of software complexity, I designed and implemented the system which accepts source program by input and measures product metrics and produce measurement value of factor items.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.2
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• pp.91-101
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• 2012

A 200 W portable polymer electrolyte membrane fuel cell (PEMFC) system is developed. The PEMFC system consists of an air-cooled fuel cell stack module, a fuel supply subsystem, a power management subsystem, and a control electronics subsystem. The control logic is designed for the stable system operation. The system-level performance evaluation discloses that the present PEMFC system provides a rated power output of 200.5 W at 13.4 V with the maximum balance-of-plant (BOP) efficiency of 72%, and maximum system efficiency based on lower heating value (LHV) is 37% at 120.7 W system power output.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.328-333
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• 2007

The purpose of this study is modelling of system air-conditioner for TRNSYS. System air-conditioner is operated by a variable capacity compressor and accommodated by multiple evaporators. By reason of these feature, realizing performance of system air-conditioner for TRNSYS was incomplete. In this study performance data of system air-conditioner and control logics are used to make system air-conditioner module for TRNSYS. Performance data contains total capacity, power input and capacity index of system air-conditioner. The simulation was carried out in a mode of temperature level control using TRNSYS 16. The simulation shows that the system air-conditioner model operate variable capacity and can compute capacity index and power input of system.