The Horsepower Reserve Formulation of Driveability for a Vehicle Fitted With a Continuously Variable Transmission

Summary A systematic methodology is developed for choosing the optimum ratio trajectory of a continuously variable transmission in a passenger vehicle. The optimum CVT ratio schedule is formulated as a constrained optimization problem with maximum fuel economy as the objective function and driveability concerns and physical limitations included as the constraints. The key notion to achieving good driveability is the introduction and definition of a horsepower reserve function that creates a consistent and desirable vehicle response under different driving conditions. Simulation results compare the optimized schedule's performance with several other possible ratio schedules, including the minimum brake specific fuel consumption map. Results from the optimized schedule indicate only a mild tradeoff between driveability and fuel economy relative to the other ratio schedules. The ratio optimization problem formulation and solution provide a novel and unique approach for systematically addressing driveability and fuel economy considerations associated with a continuously variable transmission.     

究竟哪个中国公司会最先进驻美国市场?

上月在拉斯维加斯召开美国汽车经销商联席会议时,我在J．D．Power国际圆桌会议被美国经销商狂轰乱炸,一次又一次被问及这样两个问题:谁来了?什么时候进入美国市场?     

悬索桥主缆新型防护涂装系统的应用

广东虎门大桥悬索桥主缆采用了一种有别于传统防腐观念（阴极保护）的新型主缆防护方法，该防护系统选用的聚氨酯涂料ＭａｘｉＦｌｅｘ具有极好的与钢铁粘结能力、很大的延伸率、较小的渗透率和较小的变形性，可对主缆起到很强的防护作用。介绍了该防护系统的构思、物理性能技术参数、防护系统的组成及涂装工艺。     

On the equivalence of common rearrangements for sum constrained travel estimation problems

This paper examines the problem of estimating the parameters of nonlinear sum constrained models by use of rearrangements to permit linear estimation methods. Over the years a number of different, and sometimes ingenious, techniques have been proposed but a remaining difficulty arises from the fact that different rearrangements lead to different parameter estimates. In this paper it is shown that while ordinary least squares certainly results in different estimates, generalised least squares leads to identical parameter estimates provided convergence to the true maximum likelihood estimates is achieved. In particular it is seen that estimates are invariant with choice of base or deletion of one equation and identical for the single base, multinominal logit, geometric mean and link constant versions. The findings of this paper apply to any sum-constrained model and in transportation these occur very frequently as mode choice problems, singly-constrained gravity models, and as route choice models in path assignment. While we develop all results in this paper in the context of an intercity passenger modal market share model, the transferability of these results to other problems should be recognised.     

Multi-objective signal control of urban junctions – Framework and a London case study

This paper presents an approach to multi-objective signal control using fuzzy logic. The signal control uses fuzzy logic where the membership functions are optimised according to the Bellman–Zadeh principle of fuzzy decision-making. This approach is both practical for the decision-maker and efficient, as it leads directly to a Pareto-optimal solution. Signal control priorities are ultimately a political decision. Therefore the tool developed in this research allows the traffic engineer to balance the objectives easily by setting acceptability and unacceptability thresholds for each objective. Particular attention is given in the example to pedestrian delays. The membership functions of the fuzzy logic are optimised by a genetic algorithm coupled to the VISSIM microscopic traffic simulator. The concept is illustrated with a case study of the Marylebone Road–Baker Street intersection in London at which pedestrians as well as vehicle flows are high. The results prove the feasibility of the framework and show the vehicle delays for a more pedestrian friendly signal control strategy.     

Prediction of ship steering capabilities with a fully nonlinear ship motion model. Part 1: Maneuvering in calm water

This paper introduces a new method for the prediction of ship maneuvering capabilities. The new method is added to a nonlinear six-degrees-of-freedom ship motion model named the digital, self-consistent ship experimental laboratory (DiSSEL). Based on the first principles of physics, when the ship is steered, the additional surge and sway forces and the yaw moment from the deflected rudder are computed. The rudder forces and moments are computed using rudder parameters such as the rudder area and the local flow velocity at the rudder, which includes contributions from the ship velocity and the propeller slipstream. The rudder forces and moments are added to the forces and moments on the hull, which are used to predict the motion of the ship in DiSSEL. The resulting motions of the ship influence the inflow into the rudder and thereby influence the force and moment on the rudder at each time step. The roll moment and resulting heel angle on the ship as it maneuvers are also predicted. Calm water turning circle predictions are presented and correlated with model test data for NSWCCD model 5514, a pre-contract DDG-51 hull form. Good correlations are shown for both the turning circle track and the heel angle of the model during the turn. The prediction for a ship maneuvering in incident waves will be presented in Part 2. DiSSEL can be applied for any arbitrary hull geometry. No empirical parameterization is used, except for the influence of the propeller slipstream on the rudder, which is included using a flow acceleration factor.     

An Assessment of Integrated Coastal Management Governance and Implementation Using the DPSIR Framework: KwaZulu-Natal,South Africa

Coastal areas are under increasing pressure driven by demands for coastal space, primarily though population growth, in migration and the need for space for socioeconomic activities. The pressures and associated changes to the coastal environment need to be managed to ensure long-term sustainability. South Africa has enacted an Integrated Coastal Management Act (ICM Act) to facilitate dedicated management of its coastal environment. The implementation has been met with a number of challenges, primarily relating to financial and human capacity constraints, particularly at the local government level. Given that the ICM Act devolves powers to local government, it is imperative that implementation challenges be addressed. This paper focuses on KwaZulu-Natal, one of four South African coastal regions, which is a renowned tourist destination and home to 11.1 million people (Statistics South Africa 2015 Statistics South Africa. 2015. Mid-Year Population Estimates. Statistical release P0302. Pretoria, South Africa: Statistics South Africa. [Google Scholar]). This paper considers the state of coastal management, as well as implementation challenges being experienced at a local governance level, and highlights ways to address these. Data were acquired through questionnaire surveys and semistructured interviews. The Drivers-Pressures-State-Impact-Response (DPSIR) framework was used to identify relevant ICM issues and concerns and develop potential actions for improving the implementation of coastal management activities and the ICM Act. In the assessment of the ICM governance and implementation to date, a key concern identified was a general lack of coastal management knowledge among officials. It was specifically identified that knowledgeable management and capacity-building required championing from the provincial government in order to more efficiently and effectively implement the objectives of the ICM Act through an improved understanding of the coastal environment, its functioning and management.     

用于汽车轻量化的结构粘接

人们对车辆的需求趋向于安全性更强、质量更轻且燃料利用效率更高等方面,一种采用了先进高强度钢材、工程塑料及轻质金属的轻型车车体结构也随之打入市场。如果将上述材料单独使用,就会给最大限度减轻车体质量的潜能带来限制。一种以化学基材为基础的结构粘合剂和结构泡沫塑料的应用,巧妙地将上述3种减轻车体质量的材料结合在一起,克服了安全性差．质量难以减轻和加工成本高等难题。     

外生性面神经雪旺氏细胞瘤的形成

为探讨外生性面神经雪旺氏细胞瘤的病理来源及病因 ,对 152 6耳颞骨连续切片进行组织病理学观察。结果发现 :39耳在面神经骨性管裂处显示神经外膜先天性缺损 ,神经主干由此疝出。其中31耳 ,在疝出面神经凸面有明显的雪旺氏细胞增生。这 31耳中 ,有 12耳在卵圆窗上方 ,1耳在面神经第二膝部形成小的外生性雪旺氏细胞瘤。提示 :管裂处神经外膜的先天性缺损是面神经由此疝出的组织解剖学原因。面神经疝出可能是刺激雪旺氏细胞增生 ,以致形成外生性面神经雪旺氏细胞瘤的直接原因。