参数不确定及有扰动的情况下欠驱动遥控无人潜水器鲁棒性建模、滑模控制及仿真研究（英文）

A dynamic model of a remotely operated vehicle(ROV) is developed. The hydrodynamic damping coefficients are estimated using a semi-predictive approach and computational fluid dynamic software ANSYS-CFX~(?) and WAMIT~(?). A sliding-mode controller(SMC) is then designed for the ROV model. The controller is subsequently robustified against modeling uncertainties,disturbances, and measurement errors. It is shown that when the system is subjected to bounded uncertainties, the SMC will preserve stability and tracking response. The paper ends with simulation results for a variety of conditions such as disturbances and parametric uncertainties.     

Calculating the return value using a mathematical model of significant wave height

This study presents a new method for calculating return values. The essence of the method is that it utilizes nonstationary data to calculate the return value for a region in the Northeast Pacific. The nonstationary data was obtained from a model which was previously developed for the behavior of the significant wave height as a function of time in the region. The method is illustrated by convolving two generalized Pareto distribution functions fitted to two parts of the model, computing a suitable extreme value from the new distribution function, and calculating the return value using this extreme value.     

Two-phase evaporative battery thermal management technology for EVs/HEVs

Electric vehicle’s motor draws power from battery to meet its power demand in different road profiles. Battery high discharged currents are causes of warming battery’s cells. The temperature of 40 ºC and above reduces battery life span. The rationale of fuzzy controlled evaporative battery thermal management system (EC-BThMS) development from this study is to control the battery temperature in the range of 20 ~ 40 ºC both in charging/discharging modes. The proposed system has been developed with estimating the total cooling loads and thermal behavior of the battery cells. A fuzzy controlling system has been introduced with the EC-BThMS to control the electro-compressor and the expansion valve based on the response of battery temperature sensors.A battery pack of 8.6 kWh equipped EV has been operated with 60 km/h on 0 % gradient and 40 km/h on 5 % gradient in IIUM campus while 130 km/h on 0 % gradient and 50 km/h on 3.67 % gradient in Malaysia International Formula circuit to study the battery temperature profile and percentage of battery power saving. Comparison has been made on the performance of EC-BThMS with air cooling battery thermal management system (AC-BThMS) by using same vehicle. Result shows that EC-BThMS can save energy 17.69 % more than AC-BThM 1 and 23 % more than AC-BThM 2.     

具有共轨式喷射系统的燃烧技术的新发展

新型MTU 4000系列柴油机，采用了一种新的共轨式喷射系统。它克服了传统喷射系统的典型约束，即喷射压力与柴油机转速有关，本文提出了有关燃烧技术发展的新措施，并要求充分利用共轨式喷射系统的优点，利用柴油机整个特性场中可获得的高的喷射压喷孔的数量，还可以应用更浅的活塞顶面盆槽从而将改善空气在燃烧室中的分布，最终可以降低有害物的排放和燃油消耗率。     

Financing public transport systems in Kuala Lumpur,Malaysia: challenges and prospects

Most major cities across the world today are facing an intractable challenge of financing public transport. In Kuala Lumpur for example, public transport services are somewhat poor in part because of the failure of major operators to secure ample funding. Previous funding programs implemented in the city have failed to produce a replicable model for financing public transport. Due to numerous financial problems and the dismal performance of privately owned transport firms, the State has in the recent past emerged as a key source of funding for the public transport sector in Kuala Lumpur. This article argues that, despite the insuperable challenges, prospects for the future funding of public transport in Kuala Lumpur appears to be good. The article also draws lessons from both Tokyo and Hong Kong. In order to address the funding deficit facing the public transport industry in the city it is crucial that more viable strategies and policies such as value capture and public–private sector partnerships are adopted by the urban authorities.

作用在双圆柱桩上波浪力准确解和有限差分解的比较

The wave force exerted on vertical piles of offshore structures is the main criterion in designing them.In structures with more than one large pile,the influence of piles on each other is one of the most important issues being concerned in past researches.An efficient method for determining the interaction of piles is introduced in present research.First the wave force is calculated by the exact method using the diffraction theory,then in the finite difference numerical method the force is calculated by adding the velocity potentials of each pile and integration of pressure on their surface.The results showed that the ratio of the wave force on each of the double piles to a single pile has a damped oscillation around unity in which the amplitude of oscillation decreases with the increase in the spacing parameter.Also different wave incident directions and diffraction parameters were used and the results showed that the numerical solution has acceptable accuracy when the diffraction parameter is larger than unity.     

Hydrodynamic Performance Prediction of Stepped Planing Craft Using CFD and ANNs

In the present paper, the hydrodynamic performance of stepped planing craft is investigated by computational fluid dynamics (CFD) analysis. For this purpose, th...     

船用动力控制系统可靠性仿真试验

船用动力装置控制系统的可靠性对整个系统是至关重要的。本文介绍的可靠性仿真程序，具有能好的人机界面，可实现故障树编辑的自动生成；求解系统可行度Ｒｓ（ｔ）平均故障间隔时间ＭＴＢＦ，分系统或设备模式的重要度；求解系统失效率曲线，进行不同设计方案的系统失效经曲线对比，以及不同失效率数据曲线的对比等。     

顺层岩质边坡软弱结构面加锚索剪切特性研究

采用数值模拟的方法建立三维模型,探讨在加预应力锚索情况下软弱面的剪切特性.通过改变锚索单元的参数,讨论软弱面变形特性以及剪切强度的变化规律.研究表明:在加预应力锚索后软弱面的剪切强度有所提高,并且加预应力锚索主要影响软弱面的粘聚力,而对内摩擦角的影响不大;当锚索倾角增大时,软弱面的粘聚力先增大而后减小.预应力锚索长度增加会导致软弱面粘聚力增大,但是存在一临界锚索长,当预应力锚索长大于此临界长度后,预应力锚索长对软弱面粘聚力的影响逐渐变小.在锚索无预应力情况下,软弱面的剪切应力位移曲线主要呈现出应变软化特性,在锚索有预应力情况下,则呈现出应变强化特性.