• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1998년도 추계 학술대회논문집
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• pp.19-22
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• 1998

Automatic mesh generation procedures applied to industrial now problems lead to complex mesh topologies where usually no special considerations to mesh resolution are taken. In the present study a fast and flexible solution algorithm in combination with generalized higher order discretization schemes is presented and its application to intake port calculation is demonstrated.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.225-227
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• 2006

The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) first developed ADVISOR in 1994. Between 1998 and 2003 it was downloaded by more than 7,000 individuals, corporations, and universities world-wide. In early 2003 NREL initiated the commercialisation of ADVISOR through a public solicitation. AVL responded and was awarded the exclusive rights to license and distribute ADVISOR world-wide. AVL is committed to continuously enhance ADVISOR's capabilities. Provides rapid analysis of the performance and fuel economy of conventional and advanced, light and heavy-duty vehicle models as well as hybrid electric and fuel cell vehicle models. ADVISOR Simulates the Following Vehicle Characteristics. - Optimal drivetrain component sizes that provide the best fuel economy Vehicle's ablility to follow the speed trace - Amount of fuel and/or electric energy required by various vehicle concepts - Peak power and efficiency achieved by the drivetrain components - Torque and speed distribution of the engine - Average efficiency of the transmission - Gradeability of vehicles at various velocities

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.141-142
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• 2014

This numerical study was carried out to optimize dual fuel combustion on natural gas-diesel in static chamber. Spray experiments conducted under conditions of premixed methan 0%, 5% and 10%. In the results, penetration decreases when premixed methane is increasing. Constants of numerical models were acquired from results of spray experiments to enhance accuracy of numerical study. And dual fuel engine simulation was implemented by using AVL-FIRE with acquired constants.

• 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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• 제17권2호
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• pp.20-25
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• 2009

For many years there has been a trend to increased electrical energy consumption in cars caused by the replacement of mechanical parts by electronic or mechanical devices as well as the introduction of new electronic features. Whereas the number of electrical consumers continues to increase, the battery is still the only passive power source available. Because of this reason, needs for driving power of the engine accessories such as alternator system have increased. Usually, conventional alternator system is directly driven by the crankshaft of engine with belt. Since this increase bring about additional fuel economy. To improve this system automobile makers develops new controled alternator system. This paper focuses on fuel economy improvement according to control of alternator. In this paper, researches are performed on effect of type of Alternator system on fuel economy by experiment. And it is also calculated the effect on vehicle fuel economy using computer simulation with AVL cruise software. As a result, 0.64% of vehicle fuel economy improvement can be achieved in a vehicle with controled Alternator system compared to a vehicle with conventional Alternator system in NEDC mode.

• 한국산학기술학회논문지
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• 제13권2호
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• pp.498-503
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• 2012

엔진 회전속도가 1,500rpm 이상 일 때 차량의 가속 페달을 놓은 경우 인젝터 연료분사가 중지된다. 이것을 연료차단(fuel-cut) 기능이라 부르고, 현대의 대부분의 차량들은 이 기능을 장착하고 있다. 이 기능은 많은 경우 고속도로의 내리막 구간에서 작동된다. 이렇게 연료차단이 발생하는 경우 차량의 $CO_2$ 배출 가스는 '0'이 된다. 서해안 고속도로에서 이 연료 차단 기능을 사용하면 2,000cc 승용차의 $CO_2$ 배출량은 4% 감소한다. 그리고 내리막 구간의 경우 가장 효율적인 운전 패턴을 찾기 위하여 연료차단 기능을 AVL사의 CRUISE 소프트웨어로 시뮬레이션 하였다. 연비향상을 위해서 급격한 내리막 구간일 경우 연료 차단을 위한 차량의 하한 속도를 높게 유지해야 한다는 것을 CRUISE 소프트웨어 시뮬레이션으로 알 수 있었다. 또한 가장 우수한 연비 성능은 내리막 구간 내에서 연료차단과 재가속이 완료되어야 함을 알 수 있었다.

• Journal of Advanced Marine Engineering and Technology
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• 제34권5호
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• pp.645-652
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• 2010

본 연구의 목적은 다양한 분위기 압력 하에서 커먼레일 디젤인젝터를 통해 분사되는 비증발 디젤 분무특성에 관한 연구이다. 디젤분무의 거시적 특성으로 분무관통거리와 분무각을 음영사진과 이미지프로세싱으로 연구하였다. 수치해석은 상용 CFD프로그램인 AVL-FIRE를 사용하였다. 분열모델은 WAVE모델을 사용하였으며 표준 $k-{\varepsilon}$난류모델을 적용하였다. 분무각과 Zeuch법을 적용한 연료 분사율을 수치해석의 입력값으로 사용하였다. 분무관통거리를 실험값과 비교하여 좋은 결과를 얻었고 수치해석을 통하여 노즐팁 하류방향으로 분무의 각 구간별 액적입경분포를 알아보았다.

• 한국항공우주학회지
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• 제50권12호
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• pp.857-866
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• 2022

고정익 UAV는 다른 항공기 플랫폼보다 항속거리와 항속시간에서 큰 이점을 가진다. 이러한 이유로 군에서 정찰용으로 많이 사용된다. 본 연구에서는 랜딩기어를 포함한 고정익 UAV의 모델링을 실시하고, 비행조종컴퓨터에 사용될 유도 및 제어기 설계 및 HILS 환경 구축을 실시하였다. 또한 이륙, 순항, 착륙의 모든 과정을 자동으로 수행하는 오토파일럿 시스템을 제작하였다. 연구에 사용한 고정익 UAV를 Datcom 및 AVL 공력해석 소프트웨어를 사용하여 공력계수를 추출하고 6자유도 모델링을 실시하였다. 비행조종컴퓨터는 항공기의 16개의 비행모드를 분별하여 Carrot Chasing 기반 유도 명령을 생성하는 유도기와 Nonlinear Dynamic Inversion 기법을 사용한 제어기로 구성되어있다. SIMULINK를 사용하여 구현된 모델링과 비행조종컴퓨터는 RTNgine을 사용하여 HILS 환경을 제작하여 고정익 UAV의 통합 시뮬레이션 환경을 제작하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권6호
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• pp.2429-2449
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• 2018

Dynamic data possession verification is a common requirement in cloud storage systems. After the client outsources its data to the cloud, it needs to not only check the integrity of its data but also verify whether the update is executed correctly. Previous researches have proposed various schemes based on Merkle Hash Tree (MHT) and implemented some initial improvements to prevent the tree imbalance. This paper tries to take one step further: Is there still any problems remained for optimization? In this paper, we study how to raise the efficiency of data dynamics by improving the parts of query and rebalancing, using a new data structure called Rank-Based Merkle AVL Tree (RB-MAT). Furthermore, we fill the gap of verifying multiple update operations at the same time, which is the novel batch updating scheme. The experimental results show that our efficient scheme has better efficiency than those of existing methods.

• 신재생에너지
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• 제2권2호
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• pp.23-27
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• 2006

The power split hybrid powertrain is considered to be one of the most prospective configuration for the hybrid electric vehicle (HEV). Toyota Prius, representing this type of vehicle, showed outstanding performances in fuel efficiency, emission reduction and acceleration. The excellence is largely due to the fact that it utilizes almost all operation modes of HEV. Those modes include ZEV (Zero Emission Vehicle) driving, idle stop, fuel cut-off, power assist, active charging, regenerative braking and so forth. In this paper, a few of the mode operations were simulated using AVL Cruise. Also, control logics to operate the powertrain in each mode were developed. The states of powertrain components were displayed and analyzed. By controlling the three components (engine, motor and generator), it was possible to run the powertrain in several hybrid operation modes.