• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.129-137
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• 2000

The powertrain is an important factor for the interior and exterior noise behavior of the vehicle Thus, the noise vibration and harshness(NVH) behavior of an engine is becoming a major target of the powertrain development. This paper describes the analyses with the aim to reduce the vibration and noise of an advanced inline 4-cylinder diesel engine block by use of CAE methods. The characteristics of an engine block as a main excitation source of car interior noise is studied. Particularly, The effect of balance shaft to reduce the 2nd order engine excitation force is calculated by forced vibration and radiated noise analysis. The engine exitation forces are obtained under real operating conditions. It is shown that the reduction of vibration and noise level by adapting blancing shaft is well predicted and rediated noise is directly related to the surface velocity of engine block.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.267-276
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• 1993

A kinetmatic stirling engine with a domed heater was designed, fabricated and test. In designing and fabrication of the engine various problems were confronted and solved. Among various parts of the engine, cooler and main seal needed sophisticated techniques to fabricated in order to prevent leakage of working gas from the parts and to ensure their proper functions in the engine. The engine had a series of experiment at various working gas pressure, heater temperatures and engine speeds to evaluate its performance. Indicated and brake power outputs and indicated and brake thermal efficiencies were determined from the experimental data. The engine resulted a little inferior performance to that of the GPU-3 engine of which performance was well reported . Several recommendations were made to improve the performance of the engine during the evaluation of its performance.

• Tribology and Lubricants
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• v.13 no.2
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• pp.8-15
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• 1997

It is very difficult to express the state of a tested engine objectively concerning the malfunction, failure and wear of an engine. The general method of engine evaluation is to express evaluator's opinion for the engine state after testing. However, these methods is only subjective evaluation because test engineers, designers, and evaluators does not easily coincide in opinion. Therefore, in this article, the method of engine rating are introduced in order to represent the qualitative trends into quantitative value. The purpose of Engine Rating is to assign a quantified value to the tribology state of a tested engines. Originally, this Engine Rating method have been used to evaluate the performance of engine oil quantitavely. Using this method, we can predict the proper interval of engine oil change due to its objectivity. So, we can prevent the frequent change of engine oil and protect the environmental contamination. Furthermore, this method can be used to tell the general state of a tested engine after finishing engine durability tests. A single merit scale is used to evaluate numerically the state of cleanliness and the mechanical condition. Generally, a part which is absolutely clean or shows no wear, is rated merit 10. A part which is absolutely dirty or very worn, is rated merit 0.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.73-80
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• 1999

Belief revision involves integrating new information with the current belief. It is a ubiquitous human activity. A critical feature of belief revision lies in its sequential nature. Railroad system can be described as organic. Engine drivers take a great role in this system. Recently, Hogarth and Einhorn(1992) have Posited a belief-adjustment model for updating beliefs. Based on a sequential anchoring and adjustment strategy, the model is important fro decision makers. The sequential nature of information processing is affected by some task variables. This will be mainly explained in this paper. The purpose of this study is to examine the engine drivers' belief revision process and factors which influence on the belief revision process. The factors are the order and the experience. Thereby, this will contribute to the study of engine drivers' behavior. The result of this study is summarized as follows. The order effect due to the order of presentation of the evidence exist. The difference of belief revision is due to The experience level.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.7
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• pp.86-93
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• 1999

Turbocharger has been used to increase the performance of diesel engine, especially ship engine , for years. Recently, the turbocharger is being adopted not only for an agricultural engine but also for an automobile engine. To improve the performance of diesel engine , the problem of the reduction of A/F ratio in high speed should be solved. Turbocharger is well known for its cost effectiveness, reliability and duration . In this study, an experiment was conducted to verify simulation program . The results for natural aspiration engine and turbocharged engine were compared. In order to estimate the characteristics of exhaust gas, D-13 mode was selected. Power, torque and BSFC of turbocharged engine were increased than those of natural aspiration engine by about 48%, 46% and 5%, respectively . The components in exhaust gas except NOx from turbocharger engine were less than the amount set up for 2000-year regulation.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.4
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• pp.65-69
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• 2001

Research on the development of CNG dedicated engine that has important meaning both as a clean fuel and an alterna- tive energy to reduce the exhaust emission from diesel engine are actively going on these days. In this study, in order to present the direction and application of CNG engine, we tested the CNG engine performance experimented by changing the parameters such as ignition timing, equivalent ratio. The engine performance experimented by changing the parameters such as ignition timing, equivalent ratio. The engine performance and exhaust emission were measured by engine performance model at maximum load condition with increasing the rpm in the range of 1,000∼2,200rpm. Also, the testing engine was heavy-duty CNG dedicated engine with displacement of 11,050cc.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.111-119
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• 1997

In this paper, engine-CVT consolidated control performance were investigated experimentally. Engine-CVT consolidated control was composed of engine throttle control based on power difference and CVT ratio control based on CVT ratio map. Experimental results showed that engine optimal operation was obtained while satisfying the driver's desire, i. e., following the given drive mode by engine-CVT consolidated control. Also, it was found that engine performance is subjected to inertia of the powertrain where the magnitude of acceleration changes abruptyly. Comparing with the results of CVT only control, the results of engine-CVT consolidated control showed better performance. Therefore, in order to meet the driver's desire as well as keeping the engine optimal operation, the engine-CVT consolidated control could be suggested as an integral solution.

• Tribology and Lubricants
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• v.14 no.4
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• pp.108-113
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• 1998

In order to investigate the characteristics of top ring groove deposit formation in diesel engine, engine test and simulation test were performed. From component analysis of used oils sampled from actual running engines, soot content in engine oil was selected as a main parameter for evaluating oil degradation. Deposit formation is highly related to soot content in lubricating oils. And high soot content oil accelerates deposit formation even in low temperature region below 26$0^{\circ}C$. In low temperature region below 26$0^{\circ}C$, deposit formation rate is mainly affected by top ring groove temperature. However, in high temperature region above 26$0^{\circ}C$, deposit formation rate is affected by soot content as well as top ring groove temperature. Therefore, soot content as well as top ring groove temperature should be kept a certain level in order to prevent troubles due to carbon deposit formation.

• International Journal of Contents
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• v.3 no.4
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• pp.8-14
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• 2007

This study focuses on modeling mobile 3D game engine and suggesting modified skinned-mesh schema based on JSR-184 in order to improve the performance in terms of memory consumption and time complexity. Most of the 3D games have used OpenGL-ES low-level APls, which may limit portability and fast developing time. Hence, the 3D mobile game engine providing high-level APls which works on GSM (Global System for Mobile Communication) phones on J2ME, is proposed here in order to optimize the performance for Java environment abiding JSR-184 standard. To prove performance enhancement, skinned-mesh schema on JSR-184 engine is modified and tested. The experimental results are shown.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.2
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• pp.161-167
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• 2005

The improvements of the propulsive engine efficiencies could reduce the fuel consumption. Therefore. for a marine main diesel engine the substantial increase of stroke bore ratio. so that the engine speed can be significantly reduced in order to increase the Propulsive efficiency. As a typical example. a Sulzer RTA 60C engine has acylinder diameter of 600 mm and each cylinder is capable of delivering 2.369 kW in the speed range 91-114 rpm. In order to Provide basic data for thermal system of marine engine. this work performs an experimental study of heat transfer in a square channel with one rib-roughened wall under sin91e mode of reciprocating oscillation. A selection of heat transfer measurements illustrates the manner by which the reciprocating channel with two opposite heating walls has the higher heat transfer Performance than with four heating wall.