• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2005년도 학술대회
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• pp.243-247
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• 2005

디지털 방송은 비디오, 오디오와 더불어 데이터를 전송할 수 있다. 데이터 영역에는 셋톱박스(STB)에서 수행되는 애플리케이션(Xlet)이 포함된다. 디지털 방송은 애플리케이션을 이용해 보다 진보된 인터랙티브 프로그램을 제공할 수 있다. 그러나 이러한 인터렉티브 TV에서 3차원 객체의 활용은 아직 여러 제한사항으로 인해 어려움이 있다. 현재 제정된 DVB-MHP, SCTE-OCAP, ATSC-ACAP 등의 데이터 방송 표준은 3D 객체를 표현하기 위한 구체적인 방법을 기술하지 않고 있다. 또한, 상용셋톱박스에 탑재된 자바 가상 머신(Java Virtual Machine)은 3D 객체를 렌더링(Rendering)하기 위한 API를 제공하지 않고 있다. 그리고 이를 위한 별도의 플러그인(Plug-in)도 제공하지 않는다. 본 논문에서는 Interactive TV에서 3차원 객체를 표현하기 위해 필요한 기본개념과 기술 및 데이터 방송 표준을 분석하고, 이들을 통합하여 polygon 기반의 3D Graphic Engine을 제안한다. 특히, 본 논문에서 제안하는 3D Graphic Engine API는 각각의 표준에서 가용한 공통 API를 기반으로 설계 되었으며, Java Virtual Machine 1.1 환경에서 구동될 수 있도록 구현되었다.

• 한국게임학회 논문지
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• 제6권1호
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• pp.21-28
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• 2006

본 논문에서는 OpenGL-ES 기반의 모바일 3D 블루투스 엔진을 설계 및 구현하였다. 기존 모바일 3D 네트워크 게임에서는 Wap(Wireless Application Protocol)과 VM 방식(Network)를 이용한 무선인터넷 게임이 주류를 이루고 있다. 그러나, 이들 모바일 네트워크 게임의 단점으로 지적되는 무선 네트워크 접속에 따른 지나친 통신 요금의 부담으로 인해 VM 형태를 기반으로 하는 다운로드형 게임 즉, 단독 실행형 게임이 인기를 끌고 있다. 본 논문에서는 이러한 모바일 네트워크 게임의 단점을 해결하기 위해 모바일 3D표준(C언어 기반)인 OpenGL-ES로 근거리에 있는 사람들이 무선 인터넷에 접속하지 않고, 모바일 3D 네트워크 게임을 즐길 수 있는 모바일 3D 블루투스 엔진을 제작하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.369-375
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• 2004

Gas turbine engine simulation in terms of transient, steady state performance and operational characteristics is complex work at the various engineering functions of aero engine manufacturers. Especially, efficiency of control system design and development in terms of cost, development period and technical relevance implies controlling diverse simulation and identification activities. The previous engine simulation has been accomplished within a limited analysis area such as fan, compressor, combustor, turbine, controller, etc. and this has resulted in improper engine performance and control characteristics because of limited interaction between analysis areas. In this paper, we propose a new simulation methodology for gas turbine engine performance analysis as well as its digital controller to solve difficulties as mentioned above. The novel method has particularities of (ⅰ) resulting in the integrated control simulation using almost every component/module analysis, (ⅱ) providing automated math model generation process of engine itself, various engine subsystems and control compensators/regulators, (ⅲ) presenting total sophisticated output results and easy understandable graphic display for a final user. We call this simulation system GT3GS (Gas Turbine 3D Graphic Simulator). GT3GS was built on both software and hardware technology for total simulation capable of high calculation flexibility as well as interface with real engine controller. All components in the simulator were implemented using COTS (Commercial Off the Shelf) modules. In addition, described here includes GT3GS main features and future works for better gas turbine engine simulation.

• 한국자동차공학회논문집
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• 제24권3호
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• pp.319-329
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• 2016

Globally, many researchers have been trying to improve the fuel economy of a vehicle for satisfying future $CO_2$ regulation and minimizing air pollution problem. For the same background, diesel engine and vehicle system optimization using simulation models have been key technologies for the improvement of vehicle system efficiency. Therefore, in this study, calibration method for the air breathing system of a WGT diesel engine using mean value model has been composed for efficient engine and vehicle optimization simulation researches. And virtual WGT performances have been calculated for a 2 cylinder downsized diesel engine system. From these researches, the calibration method for the boost pressure and EGR rate of a virtual diesel engine related with WGT performances could be composed and some of technical issue related with downsized diesel engine could be investigated.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2005년도 추계 종합학술대회 논문집
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• pp.19-24
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• 2005

현재의 모바일 게임시장은 플랫폼의 변화와 관련업체의 요구사항, 게임 전용폰과 게임포털 등의 등장으로 기존 저용량 2D 게임 위주의 서비스에서 이제 본격적으로 3D 게임 서비스 환경이 조성되고 있다. 본 논문에서는 최근 국내외 상용화된 모바일 3D 게임엔진의 사례를 비교 연구하여 3D 게임 엔진의 특징을 분석하고 게임 개발 환경을 고찰해보고자 한다.

• 한국추진공학회지
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• 제25권3호
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• pp.101-112
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• 2021

SpaceX는 Falcon 9과 Falcon Heavy의 재사용을 통해 다양한 탑재중량 포트폴리오를 구성하고, 한 종류의 엔진을 사용하여 발사체를 구성하며, 케로신 엔진에서 메탄 엔진으로의 전환, 3D 프린팅 사용 등 다양한 전략을 보여주고 있다. 본 연구에서는 아리랑 위성에서 천리안 위성까지 다양한 탑재중량 및 궤도를 감당할 수 있는 발사체 안을 구성하였으며, 케로신 가스발생기 사이클 엔진, 케로신다단연소 사이클 엔진, 메탄 다단연소 사이클 엔진을 사용한 10가지 발사체 안에 대해서 검토하였다. 10가지 안 중 35톤급 메탄 엔진을 사용한 재사용 발사체가 개발 가능성 측면에서 좋은 안으로 평가되었다.

• 한국자동차공학회논문집
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• 제8권3호
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• pp.12-17
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• 2000

In this study a heavy duty diesel engine was modified into a 11-liter 6-cylinder SPI CNG dedicated engine, which was tested to investigate the performance and exhaust emission under the maximum load condition as the engine speed was increased in the range of 1,000∼2,200 rpm. The exhaust emission was also measured at D-13 mode as well as AVL-8 mode.

• 한국자동차공학회논문집
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• 제22권3호
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• pp.210-219
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• 2014

The MPI dual injection engine can enhance the fuel efficiency and engine power. By using one injector per one intake port, MPI dual injection engine has an excellent fuel atomization and targeting injection. As the basic research for the MPI Dual injection engine design, this research was investigated in order to understand the characteristic of the in-cylinder flow and fuel behavior according to engine temperature condition and the fuel type in the MPI dual injection engines. The 3D unsteady CFD simulation for the MPI Dual injection engine was performed using STAR-CD. The engine operating condition was 2,000 rpm/WOT. The parameters for this study were fuel types, fuel temperatures and wall temperatures. As a result, the intake air amount, evaporated fuel in the cylinder and the fuel film on the wall were presented according to parameters that depend on the fuel properties and engine wall temperature. Also, the results were influenced by in-cylinder flow such as the intake flow, back flow and so on.

• 수산해양기술연구
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• 제16권2호
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• pp.69-76
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• 1980

This paper describes the measurement of the underwater noises produced by the engine vibration around the engine room of stern trawler MIS Sae-Ba-Da(2275GT, 3,600 PS) and pole kner M/S Kwan-Ak-San (243 GT, 1000 PS) while the ship is stopping. The underwater noise pressure level was measured with the underwater level meter of which measuring range is 100 to 200 dB(re bLPa). A and B denotes the maximum pressure level measured at right beneath the bottom of the engine room, while the main engine of the Sae-Ba-Da revoluted at 750 and 500 rpm, respectively. C denotes that of the main engine of the Kwan-Ak-San revoluted at 350 rpm, and D that of the generator of the Sae-Ba-Da revoluted at 720 rpm. Thus A, B, C and D were set for the standard sound source for the experiment. The results obtained are as follows: 1. The noise Pressure level at A, B, C and D were 170.5,165,153 and 158dB, respectively. 2. When the check points distanted vertically 1, 10, 20, 30, 40, 50m from the sound source, the underwater noise presure levels were 170.5, 155, 148, 144 and 138 dB and the directional angle was 116\ulcorner in case of A. 3. The sound level attenuated at the rate of 20dB per 10" meters of the horizontal distance from the sound sources. 4. The frequency distribution of the noise was 100Hz to 10KHz and predominant frequency was 700 to 800Hzminant frequency was 700 to 800Hz

• 수산해양기술연구
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• 제56권3호
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• pp.230-237
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• 2020

In order to design a diesel engine system and predict its performance, it is necessary to analyze the gas flow of the intake and exhaust system. A gas flow analysis in three-dimensional (3D) format needs a high-resolution workstation and enormous time for analysis. Therefore, the method of characteristics (MOC) was used for a gas flow analysis with a fast calculation time and a low-resolution workstation. An experiment was conducted on a single cylinder diesel engine to measure pressure in cylinder, intake pipe and exhaust pipe. The one-dimensional (1D) gas flow was analyzed under the same conditions as the experiment. The engine speed, valve timing and compression ratio were the same conditions and the intake pressure was inputted as the experimental results. Bent pipe such as an exhaust port that cannot be realized in 1D was omitted. As results of validation, the cylinder pressure showed accuracy, but the exhaust pipe pressure exhibited inaccuracy. This is considered as an error caused by the failure to implement a bent pipe such as an exhaust port. When analyzed in 3D, calculation time required 61 hours more based on a model of this study. In the future, we intend to implement a bent pipe that cannot be realized in 1D using 3D and prepare a method to supplement reliability by using 1D-3D coupling.