• 한국자동차공학회논문집
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• 제12권4호
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• pp.24-30
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• 2004

As the environmental pollution becomes serious global problem, the regulation of emission exhausted from automobiles is strengthened. Therefore, it is very important to know how to reduce the NOx and PM simultaneously in diesel engines, which has lot of merits such as high thermal efficiency, low fuel consumption and durability. By this reason, the new concept called as Homogeneous Charge Compression Ignition(HCCI) engines are spotlighted because this concept reduced NOx and P.M. simultaneously. However, there is trade off between output and NOx in a HCCI engine. In this study, output and emission characteristics for a gasoline direct injection type HCCI engine were investigated to clarify the effects of intake air temperature, injection time and mixture formation. From these experiments, we found that the smoke was not produced when the fuel was injected earlier than BTDC 90$^{\circ}$. In addition, the output was increased because of delay of ignition time and NOx emission was decreased because of homogeneous charge of first injection in case of split injection.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.391-394
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• 2008

Global warming and air pollution have increased the amount $CO_2$ in the atmosphere. In order to decrease the amount of $CO_2$, lots of researches are conducted toward using Hydrogen energy. Because of its high efficiency energy level and environmental friendly features, many companies have researched on developing hydrogen engine system and distributed generation system. Especially, the focus of this research provides the operation method of linear generator for hydrogen fuel combustion linear engine. During an ignition, linear generator is operated by motor to create the initial condition of engine combustion. Once the engine combustion is stabilized, the generator supplies electric power to grid. In order to stabilize the engine, linear generator is required to control mover frequency, direction, and force; Hence the PCS(Power Conversion System) place three H-bridge type inverter stacks in parallel to control phase current independently. As well, by using Back-to-Back method, it can receive electric power from both end.

• 한국항공우주학회지
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• 제34권1호
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• pp.95-102
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• 2006

펄스형 플라즈마 전기추력기의 설계기술과 제어기법에 있어서는 과거의 기술에 비하여 많은 도약을 하였다. 그리고, 펄스형 플라즈마 전기추력기의 충전된 전기에너지는 추력기 구동시 중요한 비중을 차지함을 알 수 있다. 펄스형 플라즈마 전기추력기는 매 분사시 축전기에 충전된 전기에너지를 방전시켜 분사 시키므로서 추력을 얻는 장치이다. 따라서, 매 분사시 균일한 추력을 얻고자 할 경우에는 동작시점에서 균일한 전기 에너지가 충전되어 있어야 한다. 따라서, 본 논문에서는 매 분사시 균일한 추력을 얻기 위한 기법과 축전기와 추력기 엔진간의 기하학적 연결에 따른 안정성을 연구하였다.

• 로봇학회논문지
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• 제11권4호
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• pp.270-276
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• 2016

This paper proposes a design methodology of self-reconfigurable kinematics and control engine for modular and reconfigurable robots. A modular manipulator has been proposed to meet the requirement of task adaptation in versatile needs for service and industrial robot area and the function of self-reconfiguration is required to extend the application of modular robots. Kinematic and dynamic contexts are extracted from the module and assembly information and related codes are automatically generated including controller. Thus a user can easily build and use a modular robot without professional knowledge. Simulation results are presented to verify the validity of the proposed method.

• 한국자동차공학회논문집
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• 제16권5호
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• pp.106-112
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• 2008

Modern vehicles require a high degree of refinement, including good drive ability to meet customer demands. Vehicle drive ability, which becomes a key decisive factor for marketability, is affected by many parameters such as engine control and the dynamic characteristics in drive lines. This paper focuses on the simulation of FTP-75 mode which is considered with spark timing control on transient condition. The acceleration is the most important factor for vehicle fuel economy. The retard of spark timing increases in proportion to acceleration. Likewise, bsfc(break specific fuel consumption) which is affected by spark timing also increases in proportion to acceleration. The result of simulation considered transient condition shows 0.3% of error comparing with a test on chassis-dynamometer.

• 한국분무공학회지
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• 제20권4호
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• pp.247-253
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• 2015

Recently, the engine calibration technique has been much more complicated than that of the past engine case in order to satisfy the strict emission regulations. The current calibration method for the diesel engine which has an increasing market is both costly and time-consuming. New engine calibration method is required to develop for high-quality diesel engines with low cost and release it at the appropriate time. This study provides the optimal calibrating technique for complex engine systems using statistical modeling and numerical optimization. Firstly, it design a test plan based on Design of Experiments, a V-optimality methodology which is suitable looking for set-points, and determine the shape of test engine response. Secondly, it uses functions to make linear regression model for data analysis and optimization to fit the models of engines behavior. Finally, it generates the optimal calibrations obtained directly from empirical engine models using Grey Relational Analysis and compares the calibrations with data. This method can develop a process for systematically identifying the optimal balance of engine emissions.

• 동력기계공학회지
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• 제22권1호
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• pp.5-10
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• 2018

In order to employ factorial design on electronically-controlled diesel engine, effects of 5 factors on specific fuel consumption, nitrogen oxides and carbon monoxide were examined by fractional and full factorial design in this research. There were different results between fractional and full factorial design, then effect of variables as ambient condition and measurement of fuel consumption were confirmed. It was shown that ambient condition affected uniformly trend of nitrogen oxides and carbon monoxide. However, both ambient condition and measurement of fuel consumption had nothing to do with trend of specific fuel consumption and therefore it must be careful to employ factorial design on specific fuel consumption as response.

• 한국콘텐츠학회논문지
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• 제18권1호
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• pp.1-9
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• 2018

본 논문에서는 눈을 깜빡(eye-blink)일 때 발생하는 안전도(EOG, electro-oculogram) 신호를 이용하여 손을 사용하지 않는 가상현실 HMD(head mounted display)용 키보드 시스템을 제안하였다. 본 시스템은 디스플레이 소자, 자이로스코프센서, 중력센서, 뇌전도(EEG, electro-encephalogram) 센서 등으로 구성되며, 시스템의 제어 및 그래픽 처리 등을 위한 Unity3D 엔진으로 가상현실 HMD용 키보드 시스템을 구현하였다. 구현된 키보드의 방식은 한글의 경우 천지인 키보드 방식을 사용하였으며 영어, 숫자, 기호의 경우 $3{\times}4$ 방식을 사용하여 공간상의 문제를 해결하였다. 구현된 시스템을 통해 손을 사용하지 않고 목의 움직임과 안전도만으로 가상현실 HMD의 키보드 입력이 가능함을 확인하였다.

• 드라이브 ㆍ 컨트롤
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• 제14권1호
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• pp.35-40
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• 2017

Whereas fuel economy of a vehicle is measured using a chassis dynamometer, that of construction machinery such as an excavator shall be presumably measured using simulated work cycle. In order to measure fuel consumption under a simulated work cycle, a measurement methodology, while excavator operates in dynamic(transient) motion, needs to be examined and developed. In this work, three methods (gravimetry, ECU CAN signal and mass flow meter) are studied and compared. This work reveals that when ECU CAN signal is properly calibrated and evaluated, compared to gravimetry or mass flowmeter, it could be used to measure fuel consumption with accuracy and thus for approval of the fuel economy of construction machinery.

• 대한전자공학회논문지TC
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• 제46권10호
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• pp.34-42
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• 2009

HAO는 로직 기반의 코바 컴포넌트 개발을 수용하기 위해 FPGA에 탑재되는 ORB엔진이다. 본 논문은 표준 코바와 HAO 간 연동을 제공하기 위한 과정으로, 표준 ORB간 연동 프로토콜인 GIOP의 구체화 방안에 대해 기술한다. 구체적으로, 시스템 보드의 하드웨어 자원을 직접 사용한다는 관점에서 HAO Core가 하드웨어 독립성을 갖도록 하여야 하며, 공유 자원에 대한 빠른 제어 반환을 고려한 최적화 방안을 포함해야 한다.