"交叉式数据线"在公共汽车和货车自动变速器中的应用

“交叉式数据线”是变速系统的最新研究内容，它能减少装配工作及提供附加功能，使用户获利。特别对目前仍配置手动变速器的长途公共汽车和货车，今后将设计成电控的“自动化手动”变速系统。车辆数据的总线系统、道路数据的总线系统和变速器集成化的机电模式是实现技术和为进一步改进提供巨大潜力的关键。ZF－AS Tronic作为ZF公司最新的自动变速系统采用了那些用于正常操作的技术并提供了高的寿命和驾驶舒适性，其优点是适合于所有使用者－车辆制造者、运输公司和驾驶员。全电子控制系统的典型特点是具有分布式模式结构、高网络功能和软件结构的可扩展能力。AS－Tronic将变速器的功能从简单的“变矩器功能”转变为现代化的“传动链操纵系统”。     

Status,causes and controls of cyanobacterial blooms in Lake Erie

The Laurentian Great Lakes are among the most prominent sources of fresh water in the world. Lake Erie's infamous cyanobacterial blooms have, however, threatened the health of this valuable freshwater resource for decades. Toxic blooms dominated by the cyanobacterium Microcystis aeruginosa have most recently been one of primary ecological concerns for the lake. These toxic blooms impact the availability of potable water, as well as public health and revenues from the tourism and fishery industries. The socioeconomic effects of these blooms have spurred research efforts to pinpoint factors that drive bloom events. Despite decades of research and mitigation efforts, these blooms have expanded both in size and duration in recent years. However, through continued joint efforts between the Canadian and United States governments, scientists, and environmental managers, identification of the factors that drive bloom events is within reach. This review provides a summary of historical and contemporary research efforts in the realm of Lake Erie's harmful cyanobacterial blooms, both in terms of experimental and management achievements and insufficiencies, as well as future directions on the horizon for the lake's research community.     

Evaluation of Performance of Diesel Particulate Filters Through Integrated Multi-Scale Computer Calculations

Wall-flow channel models and soot deposition models based on micro scale considerations are integrated into global 3D diesel particulate filter simulations. In addition, transient and steady-state simulations are combined to understand at the same time short- and long-time behaviour of the diesel particulate filter (DPF). The functionality of the simulation tool is achieved and correlations with measured data encourage the use of the model as a tool to predict DPF behaviour.     

Dairy cows trapped between performance demands and adaptability

The tremendous increase in the lactation performance of dairy cows during the last 60 years has had dramatic consequences on fertility and vitality (fitness) of the animals. Unprecedented average lactation performance levels have resulted in an equally unprecedented reduction in longevity. Economic pressure to further reduce the age at first calving is still high, although the negative correlation between precocious maturity and longevity is well documented in the relevant literature. Ever more aggressive selection and feeding measures are being taken to shorten the rearing time of heifers in order to reduce the cost of replacement heifers. An additional decrease in the stayability of cows has to be expected when the age at first calving is lowered even further. For reasons of profitability, dairy cows should complete an average of at least four lactations. Cows from the most important dairy breeds in the United States and Bavaria, Germany, already dropped below that crucial threshold many years ago. The same phenomenon has been observed in dairy cows in Austria over the past few years. Holstein cows that were culled in Austria in 2007 had an average of only 3.3 parities. To improve this situation, dairy cattle breeding programs should put a much higher emphasis on selection for traits of longevity and lifetime performance and, in return, markedly reduce the emphasis on selection for lactation performance in general and early‐lactation performance test results in particular. Over millions of years of evolutionary adaptation, cattle have acquired the ability to utilize fibrous low‐quality plant substrate. Only a strongly forage‐based feeding regimen is, in the long run, in accordance with their digestive and metabolic configuration. The massive use of concentrates (mostly grain) in cattle rations increases the risk of digestive and metabolic disorders in cattle and consequently leads to impaired animal welfare. Finally, the careful management of scarce resources demands that a closer look be taken at the food balance in dairy rations, i.e., an awareness of how much food that is edible for humans is being fed to livestock. Copyright © 2009 Society of Chemical Industry     

伊泰普工程设计和施工中的风险分析与管理

1　引言伊泰普水电工程为巴西和巴拉圭两国共有,并共同管理和运行。1970至1974年,对两国共有的巴拉那河界河河段,进行了广泛的可行性研究,确认了工程的规划设计方案。工程施工始于1975年5月2日。1978年10月20日实现了明渠导流。1982年10月23日水库蓄水至溢洪道高程。首台700ＭＷ机组于1984年5月5日开始投入运转。1991年4月10日,装机总容量12600ＭＷ水电站的第18台机组投产。对这个巨型工程的规划、设计和施工过程中进行关键决策时,应用风险分析与管理方法的若干成功实例予以介绍。工程最终的成功,包括其安全性、长期运行的可靠性以及工程的…