摩托车发动机冷却水套流场特性研究及结构改进

选取CFD流体分析软件STAR-CCM+对摩托车发动机冷却水套进行流场数值模拟及结构改进研究.结果表明,水套原方案缸孔布局不合理,导致冷却水套冷却液流动均匀性较差,排气侧及火花塞侧高温区域冷却较差,不利于高温区域冷却.在水套原方案上减小进气侧缸孔流通面积后,排气侧及火花塞侧冷却液流速明显提升,冷却液利用率提高,保证了高温区域的有效冷却.实验测试结果显示冷却水套结构改进后发动机的缸温降低8℃,表明冷却水套改进结构有效,冷却性能提升明显.研究方法及结果可为摩托车发动机冷却水套的结构设计提供理论参考.     

Business strategy and the management of digital marketing

The internet brought disruptive change to the business landscape through the creation of a whole host of digital marketing tactics. But with these new tactical options has come the need for marketing managers to (1) prioritize what they wish to accomplish and (2) determine which digital marketing tactics to invest in. We consider these issues from the perspective of four business strategies: prospectors, analyzers, low-cost defenders, and differentiated defenders. In this article, we provide marketing managers with insights into how businesses pursuing various strategies approach these digital marketing issues, with the ultimate goal being to assist managers in the efficient and effective implementation of their firm’s adopted strategy.     

Eco-driving by replicating best driving practices

Some transit companies have reduced up to 25% of their fuel consumption by training their drivers on eco-driving. We propose to further reduce fuel consumption by using best driving practices, which consist of guiding drivers on the recommended ranges of vehicle speed and engine RPM that lead to minimum fuel consumptions. These recommendations are obtained by monitoring the engine operational parameters used by drivers who have shown the lowest fuel consumption while driving vehicles of similar technology and running on the same section of the road. To demonstrate the applicability of this alternative, we monitored a fleet of 15 transit buses of recent technology serving a ～72-km long route of general characteristics during eight months of normal operation. For each kilometer, trips with the lowest fuel consumption were selected, and their interquartile ranges of RPM and speed were obtained. Then, a well-trained driver in eco-driving traveled over the same road with same type of buses, using these recommended ranges. Using his eco-driving training, he obtained a 0.5% reduction in fuel consumption with respect to the average of the population, and by using the best driving practices, his savings increased up to 10.1%. These savings were linked to an increase in the average energy efficiency of the engine from 27.6% to 28.9%, which demonstrates that when drivers use these best driving practices, they tend to operate the engine under conditions closer to the load—RPM engine area of engine highest efficiency.     

电控汽油/CNG两用燃料发动机氧传感器故障模拟试验

在自行开发的汽油/CNG两用燃料发动机故障模拟试验台上,完成了氧传感器的故障模拟试验,对比研究了故障对发动机动力性、经济性和排放等性能的影响。试验结果表明:氧传感器信号丢失后,怠速时转速下降,HC排放增加,CO和NOx排放降低;中等负荷时转矩和功率下降,气耗和比气耗下降,CO和NOx排放减少,HC排放增加;氧传感器信号失真后,ECU不能根据真实情况调节混合气的浓度,发动机运行状况与期望相差很大。     

分布式智能垂直搜索引擎系统的设计

本系统旨在开发一个网络环境下的分布式智能垂直搜索引擎系统,其所处理的原始对象以网页为主,它们分散在整个网络图的不同节点上,为提高平台的智能化、自动化,必须把平台作为一个整体进行开发,实现数据的自动采集(网络爬虫)、数据的信息抽取问题(网页解析),数据的高效加工(索引、存储、聚类),数据的有效利用(检索、聚类),最终形成一个统一的系统,实现并完善为解决这些问题所需要的基础环境(分布式存储与并行计算)。     

基于视景仿真技术的漫游系统的设计与实现

本文介绍了视景仿真技术在漫游系统中的具体应用。分析了用视景仿真技术进行系统实现时的两个关键环节,即三维模型的构建和漫游驱动引擎的实现,选择了MultiGen和OpenGVS作为漫游系统的开发平台,论述了从三维模型的构建到漫游驱动引擎实现的整个系统实现过程。     

Supporting capacity sharing in the cloud manufacturing environment based on game theory and fuzzy logic

This paper proposes a Framework for Capacity Sharing in Cloud Manufacturing (FCSCM) able to support the capacity sharing issue among independent firms. The success of geographical distributed plants depends strongly on the use of opportune tools to integrate their resources and demand forecast in order to gather a specific production objective. The framework proposed is based on two different tools: a cooperative game algorithm, based on the Gale–Shapley model, and a fuzzy engine. The capacity allocation policy takes into account the utility functions of the involved firms. It is shown how the capacity allocation policy proposed induces all firms to report truthfully their information about their requirements. A discrete event simulation environment has been developed to test the proposed FCSCM. The numerical results show the drastic reduction of unsatisfied capacity obtained by the model of cooperation implemented in this work.     

项目管理在发动机试车台测控系统建设项目中的应用

本文介绍了在发动机试车台测控系统建设中引入项目管理理念,遵循项目管理各过程,结合项目实际情况有效管理,最终完成项目,达到客户要求。     

基于单片机的校园智能同步电波钟的设计

本文介绍了一款高度同步的电波时钟的设计与制作。设计利用磁棒天线接收国家授时中心发射的68.5kHz长波时间信号,通过单片机进行实时解码,获取时间基准信号,用来校正电波时钟。实验结果表明,该电波钟在教室内使用能够实现显示时间高度准确且同步。     

基于IOS平台塔防游戏的设计与实现

目前随着我国3G网络的快速发展,智能手机的市场也日益扩大,其中最受欢迎的莫过于苹果公司生产的iPhone手机。本文介绍基于IOS平台的拥有良好操作性及娱乐性的小型塔防游戏开发过程。该游戏是运用Cocos2d引擎以及Xcode进行开发的,不仅实现了塔防游戏的基本对战功能,还增添了场景选择,音效设置等功能,游戏界面唯美,动画效果精彩,为手机游戏开发提供了参考。