• 제어로봇시스템학회논문지
• /
• 제21권7호
• /
• pp.691-698
• /
• 2015

Inertial Navigation Systems (INS) are widely used as the main navigation device for aircraft. To get the initial attitude, the INS requires the initial alignment before navigation starts. An aircraft also needs an engine test procedure that causes some vibrations before flight. An INS can't be aligned in a vibration environment so the initial alignment is performed before the aircraft engine test. Therefore, the initial alignment time of an INS has been a major factor in limiting an aircraft's takeoff response time. In this paper, we designed an initial alignment algorithm that can be executed even in disturbances such as aircraft run-up. We demonstrated verification of the algorithm that is embedded on the real INS and testing methods to evaluate the alignment of the INS. We also analyzed the test results of the proposed initial alignment algorithm that is performed during a real aircraft run-up.

• 대한전자공학회논문지TE
• /
• 제42권4호
• /
• pp.15-20
• /
• 2005

엔진오일 교환 시기 예측은 엔진의 수명을 연장하고 연비를 증가시킨다. 그러나, 엔진오일의 교환 시기는 자동차를 주행한 거리나, 장거리를 운행한 차량, 단거리를 운행한 차량, 엔진오일의 종류 등에 따라서 크게 달라진다. 본 논문에서는 엔진오일 교환 시기를 예측함에 있어서 단지 주행 거리나 엔진오일의 색깔의 변화 등의 데이터를 퍼지 및 신경망 알고리즘을 이용하여 값을 구하였다. 모의실험결과, 지능형 엔진오일 교환 시스템이 기존의 사람이 예측하여 결정하는 방식 보다는 더 정확하게 엔진 오일을 교환할 수 있음을 입증할 수 있었다. 따라서 지금의 자동차에 이러한 알고리즘을 적용한다면 보다 편리한 차량이 될 것으로 기대한다.

• 한국자동차공학회논문집
• /
• 제7권7호
• /
• pp.167-180
• /
• 1999

A control-oriented nonlinear dynamic engine model is developed to represent a spark ignited engine over a wide range of operating conditions. The model includes intake manifold dynamics,. fuel film dynamics, and engine rotational dynamics with transport delays inherent in the four stroke engine cycles. The model is mathematically compact enough to run in real time, and can be used as an embedded model within a control algorithm or an observer. The model is validated with engine-dynamometer experimental data, and can be used in design and development of a powertrain controller.

• 한국시뮬레이션학회:학술대회논문집
• /
• 한국시뮬레이션학회 2003년도 추계학술대회 및 정기총회
• /
• pp.51-57
• /
• 2003

In operating distributed systems, proactive management is one of the major concerns for better quality of service and future capacity planning. In order to handle this management problem effectively, it is necessary to analyze performances of the distributed system and events generated by components in the system. This paper provides a rule-based event parsing engine for proactive management. Our event parsing engine uses object hooking-based and event-token approaches. The object hooking-based approach prepares new conditions and actions in Java classes and allows dynamically exchange them as hook objects in run time. The event-token approach allows the event parsing engine consider a proper sequence and relationship among events as an event token to trigger an action. We analyze the performance of our event parsing engine with two different implementations of rule structure; one is table-based and the other is tree-based.

• 한국게임학회 논문지
• /
• 제6권4호
• /
• pp.79-87
• /
• 2006

본 논문은 기계학습 기법을 이용한 게임 캐릭터를 제어하는 엔진을 설계하고 구현하는 것을 제안한다. 제안된 엔진은 실제 게임에서 상황 데이터를 추출하여 지식 데이터로 사용하므로 지능 캐릭터의 행동 패턴을 게이머들이 쉽게 인식하지 못하는 장점이 있다. 이를 위하여 상황 데이터를 추출하여 학습하는 모듈과 임의의 상황 데이터에 대하여 최적의 상황 제어를 판단하는 시험 모듈을 개발하는 것을 제안하였다. 구현된 엔진은 FEAR에 이식되고 Quake2 게임에 적용되었다. 또한 개발된 엔진의 올바른 동작과 효율성을 위하여 다양한 실험을 하였다. 실험으로부터 개발된 엔진이 올바르게 동작할 뿐만 아니라 제한된 시간 내에 효율적으로 동작함을 알 수 있었다.

• Journal of Advanced Marine Engineering and Technology
• /
• 제32권8호
• /
• pp.1303-1308
• /
• 2008

Keeping cooling water temperature higher within the allowable range helps marine engines to run in more efficient condition especially when the engine load is low. Temperature control of jacket cooling water in outlet side of main engine has been more widely adopted to ships these days for the purpose to reduce fuel consumption rate. But If the temperature sensor for the control loop is placed at the outlet of engine, it brings more difficulties in attaining stable and desirable properties due to dead times included in pipe length and engine itself comparing to the case where the measuring point is at the inlet side of main engine. In relation with this problem, Feed-forward control could be one of realistic solutions as it reveals good properties and requires less cost for system configuration. This study suggests a forward control system which leads to improved temperature control performances to disturbance signals which could arise from variation of engine load or weather condition. Two dead times in the modelling were described, considering pipe length between the actuator and the engine as well as the thermal process inside the engine. The results of analysis were shown by simulations to confirm responses under different conditions.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
• /
• 제12권6호
• /
• pp.379-385
• /
• 2006

가변적인 컴포넌트의 재사용성이나 적응성을 높이기 위해 룰 기반 컴포넌트 개발 방법들이 제안되고 있다. 룰 기반 컴포넌트 개발에서 사용하는 룰 엔진들은 룰을 표현하기 위해 추가적인 스크립트 언어가 필요하며 따라서 복잡한 비즈니스 룰을 표현하는데 어려움이 많다. 본 논문에서는 다양한 룰 표현과 성능 향상을 위한 컴파일러 기반의 룰 엔진을 제안한다. 제안한 룰 엔진은 룰의 컨디션과 액션 부분을 표현하기 위해 자바 프로그래밍 언어를 사용한다. 따라서 복잡한 비즈니스 룰을 쉽게 표현할 수 있으며 실행 시에 동적으로 룰의 컨디션과 액션 객체를 생성해서 실행시킬 수 있다. 성능 면에서도 제안한 룰 엔진은 스크립트 기반 룰 엔진보다 우수하다. 성능 실험에 의하면 컴파일러 기반의 룰 엔진 성능은 스크립트 기반 룰 엔진인 JSR-94 보다 2.5배의 높은 성능을 보이고 있다.

• 오토저널
• /
• 제10권6호
• /
• pp.72-84
• /
• 1988

Engine performance is one of the main objectives specified at the beginning of a new engine design project. The cycle simulation for SI engine is based on the zero-dimensional gas exchange model and a heat release expression by Viebe. This program also requires minimum input data and takes only a short time to run. Heat transfer from cylinder transfer formula. The flow coefficient (effective area) is calculated from valve lift using the standard flow coefficient curve and engine friction is calculated from the Millington and Hartles' engine friction formula. The chemical species considered in burned gas are 6 species CO, CO, H$_{2}$, H$_{2}$O, $O_{2}$, N$_{2}$ and the cylinder pressure, homogeneous cylinder temperature, gas composition and burned fraction are calculated at each crank angle through the cycle. To check the validity and accuracy, experimental study was done with 3 engines for measuring cylinder pressure, indicated mean effective pressure, brake mean effective pressure and air flow rate, etc. Despite its simple assumptions, cycle simulation showes excellent breathing and performance correlation when compared with data of tested engines, and have been proved useful in engine design.

• 한국자동차공학회논문집
• /
• 제15권2호
• /
• pp.22-27
• /
• 2007

Our environment is faced with serious problems related to the air pollution from automobiles in these days. In particular, the exhaust emissions of diesel engines are recognized as main causes of the air pollution. CRDI(common rail direct injection) diesel engine is widely used for the sake of minimization on exhaust emission. Because biodiesel fuel is a renewable and alternative fuel for diesel engine, its usability is expanded. In this study, a common rail diesel engine was run with 5% of biodiesel fuel(BDF 5%) more than 150 hours. Engine dynamometer testing was completed at regularly scheduled intervals to investigate the engine performance and exhaust emissions. The data of engine performance and exhaust emissions was sampled at 1 hour intervals for analysis. When a common rail diesel engine runs on BDF 5% for long time, power and energy consumption of the engine are similar to the case using diesel fuel. The smoke emission of BDF 5% was reduced in comparison with diesel fuel, that is, it was reduced approximately 15% at 4000rpm, and load of 90%. And, CO and $CO_2$ were reduced, too. On the other hand, NOx emission of biodiesel fuel was slightly increased about 2%, but it was almost same as a commercial diesel fuel.

• 한국정보처리학회논문지
• /
• 제7권2호
• /
• pp.328-336
• /
• 2000

본 논문에서는 사용자가 멀티미디어 문서를 쉽게 제작할 수 있고, 실행시 동적 프리젠테이션을 지원할 수 있는 멀티미디어 저작 시스템을 제안하고 있다. 본 시스템의 특징으로서는 미디어간의 시간 관계를 인과 관계를 바탕으로 새롭게 정의함으로서 실행 중에 발생될 수 있는 미디어들의 실행 시간 변경을 효과적으로 처리하고 있다. 또한, 멀티미디어 문서 저작중 발생될 수 있는 일관성 오류를 즉시 검증하여 피드백하는 동적 저작 기능을 지원하고 있다. 본 저작 시스템에서는 저작내용이 파싱 단계를 거치면서 트리 형태의 내부 구조로 표현되고 있으며, 실행 시간에 동적 프리젠테이션과 사용자 상호작용을 지원하기 위한 프리젠테이션 엔진이 개발되었다.