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911.
船舶在规则纵浪中的混沌运动 总被引:2,自引:0,他引:2
Parametric resonance can lead to dangerously large rolling motions, endangering the ship, cargo and crew. The QR-factorization method for calculating (LCEs) Lyapunov Characteristic Exponents was introduced; parametric resonance stability of ships in longitudinal waves was then analyzed using LCEs. Then the safe and unsafe regions of target ships were then identified. The results showed that this method can be used to analyze ship stability and to accurately identify safe and unsafe operating conditions for a ship in longitudinal waves. 相似文献
912.
Solid oxide fuel cell (SOFC) has been identified as an effective and clean alternative choice for marine power system. This paper emphasizes on the dynamic modeling of SOFC power system and its performance based upon marine operating circumstance. A SOFC power system model has been provided considering thermodynamic and electrochemical reaction mechanism. Subcomponents of lithium ion battery, power conditioning unit, stack structure and controller are integrated in the model. The dynamic response of the system is identified according to the inertia of its subcomponent and controller. Validation of the whole system simulation at steady state and transit period are presented, concerning the effects of thermo inertia, control strategy and seagoing environment. The simulation results show reasonable accuracy compare with lab test. The models can be used to predict performance of a SOFC power system and identify the system response when part of the component parameter is adjusted. 相似文献
913.
一、案情简介某海事部门诉中石化粤东石油公司救助合同纠纷一案,广州海事法院于2005年5月19日受理后,依法组成合议庭,于7月7日召集双方当事人进行庭前证据交换,同日公开开庭进行了审理,本案现已审理终结。 相似文献
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Hyunkyu Kim Kyungsik Shin Iljoon Chang Kunsoo Huh 《International Journal of Automotive Technology》2018,19(6):1013-1022
The Autonomous Emergency Braking (AEB) systems have been actively studied for the safety enhancement and commercialized for the past few years. Because the driver tends to overly rely upon active safety systems, AEB needs to be designed to reflect the real road situations such as various road slope and friction coefficient. In this study, an AEB control algorithm is proposed to compensate for the effects of the slope and the friction of road. Based on the maximum possible deceleration for the real road conditions, the minimum braking distance is described with margin parameters for AEB activation control. The deceleration controller with a feedforward term is designed to avoid the collision during AEB operation on real road conditions. The proposed algorithm is validated in simulations first and the experimental verification is performed in the various slope conditions. 相似文献
916.
Jae Woo Chung Nam Ho Kim Deok Jin Kim Seong Sik Jang 《International Journal of Automotive Technology》2018,19(2):209-220
Recently, to improve vehicle fuel economy, as well as the performance of internal combustion engines, optimized system matching between a vehicle’s drivetrain and engine has become a very important technical issue. For this reason, the need for simulation research on engine and vehicle performance improvement has increased. But in general, since both engine simulation and vehicle simulation require initial engine calibration map input, a simple engine calibration method is required for the efficient configuration of various virtual engine calibration map setups. On this background, in this study, an example of waste gate turbocharger (WGT) cooled — exhaust gas recirculation (EGR) Diesel engine calibration using a test-based mean value engine model is presented as a suitable engine calibration map setting method. Also, the feasibility of an engine calibration model is confirmed through various engine tests. Using the simple model presented here, it is possible for diverse engine operating conditions and engine performance maps to be acquired. 相似文献
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