浅谈航线工作中的线路检查

不管航空技术发展再快,技术再先进,系统的线路故障是都是不能避免的。几乎每一个系统都有电气线路的连接,而线路的故障在飞机所有故障当中占了相当大的比例,除了直接导致系统失效,还可能出现跳火,燃烧等现象,对安全的影响很大。本篇文章主要讲解线路分布在飞机不同的区域,不同的位置,受到环境温度,湿度,其他系统部件机械运动的影响等,其故障具有隐蔽、复杂、多样的特点,又由于排故时需要认真去测量检查,用的时间也相对较长,成功率依然偏低,还往往容易出现误换件,造成维修成本增加。     

A methodology for prioritising HSR corridors: from U.S. theory to Spanish practice

The assessment of methodologies to prioritise the construction of new high-speed rail (HSR) corridors has recently become a key issue for transport planners in countries like the U.S., where HSR does not exist. In a climate of financial instability since the onset of the global crisis of 2007–2008, support for new projects is being eroded by serious concerns over the extremely steep costs of high-speed rail, and there is a need for the scientific clarification of the procedure for prioritizing construction.In 2009 a new ranking methodology was developed and applied to 30,000 city pairs in the U.S. to determine their suitability for high-speed rail investment. The existing literature on ranking tools for prioritising HSR corridors is practically non-existent, and, as none of these U.S. lines has been built or put into in operation, this methodology has not been validated. The main aim of this paper is to contribute to these ranking models and highlight their importance in the HSR planning process. The preliminary ranking tool described in this work has been validated using data from the current HSR Spanish network. The results confirm the consistency of the model as a first approach to ranking pairs, mainly for the top O–D relations; however the model has some drawbacks chiefly due to the type of variables used, and their assigned weightings. Finally, some specific improvements are proposed for this ranking approach in order to provide policymakers with a useful tool when planning the construction of new HSR networks.     

Optimization of postal express line network under mixed driving pattern of trucks

Details about the movement of trucks on postal express lines are investigated to improve the performances of mail distribution. A mixed driving pattern of trucks is introduced to minimize the transportation cost of a postal express line network with a service level requirement. We formulate this problem as a mixed p meeting depots location with shipment scheduling problem and build a MINLP model. A two-level tabu search procedure based on shipment grouping method is developed. Through a series of computational experiments and sensitivity analysis on different instances, some managerial insights of the network under mixed driving pattern are revealed.     

Risk analysis of the EASA minimum fuel requirements considering the ACARE-defined safety target

We present the results of flight simulator experiments (60 runs) with randomly selected airline pilots under realistic operational conditions and discuss them in light of current fuel regulations and potential fuel starvation. The experiments were conducted to assess flight crew performance in handling complex technical malfunctions including decision-making in fourth-generation jet aircraft. Our analysis shows that the current fuel requirements of the European Aviation Safety Agency (EASA) are not sufficient to guarantee the safety target of the Advisory Council for Aviation Research and Innovation in Europe (ACARE), which is less than one accident in 10 million flights. To comply with this safety target, we recommend increasing the Final Reserve Fuel from 30 min to 45 min for jet aircraft. The minimum dispatched fuel upon landing should be at least 1 h.     

创新铁路新线管理模式 快速形成运输能力

面对新线集中投入运营,高速客运专线及电气化新设备从无到有的新形势,乌鲁木齐铁路局采取＂延伸管理＋业务外包＂的新线管理模式,确保实现安全标准、质量标准、管理标准、技术标准和作业标准＂五统一＂,快速形成新线运输能力,有效提高全局整体管理水平。     

哈大客运专线引入哈尔滨枢纽方案研究

按不同引入方式对拟建的哈大客运专线引入哈尔滨枢纽的方案进行了分析,确定了动车段的位置,并对各种引入方案的优缺点进行了比较。结合哈尔滨市的城市发展规划,在考虑与公共交通体系整体配合等相关问题的基础上,探讨了新建专线客运站的位置,分析了客运专线与既有铁路的衔接和运营分工。     

A Tribute to Our Founding Father,Professor Bernard J. “Bud” LaLonde

This editorial pays tribute to the founding editor of the Journal of Business Logistics, Professor Bernard J. “Bud” LaLonde, who passed away recently. Professor LaLonde's influence on the field—and the individuals that compose it—is immeasurable. We reflect on his career, achievements, and motivations for creating JBL. Further, we attempt to build on his proud legacy with an introduction of articles featured in the current issue.     

The Effect of Probabilistic Selling on the Optimal Product Mix

Determination of the merchandize assortment is an important decision for retailers since the composition and depth of the product mix greatly impact both unit sales and costs. This paper considers how Probabilistic Selling (PS), an emerging marketing strategy, impacts the type and number of products a retailer should carry. We find that adopting PS can alter the optimal number of products (i.e., encourage the retailer to offer more or fewer products), depending on demand- and supply-side factors. Furthermore, introducing probabilistic goods sometimes increases the optimal degree of product differentiation and sometimes reduces it. Specifically, less differentiated products are warranted if there are either few or many consumers with extreme tastes, but more differentiation is needed otherwise. Our analysis reveals that PS can serve either as a substitute to new product introduction (because it enables a retailer to serve a diverse market at a lower cost) or as a complement to new product introduction (since, under PS, a new product enables a retailer to offer additional probabilistic goods that utilize this new product as one of its components). In sum, our results indicate that a retailer must adjust its merchandize assortment appropriately in order to fully benefit from probabilistic selling.     

Sound Security,Safe Beijing

With the approach of the longawaited event, Chinese authorities have geared up to intensify security prepa-rations. In line with the ＂people-oriented＂ and ＂athletes-centered＂ ideas, Beijing will spare no efforts to provide quality services and to build a safe and comfortable environment that will satisfy all the Games＇ participants.     

Sinosteel：Extraordinary Moves in Industry Chess

Among the Fortune 500 firms,more and more images from China emerge out.On the 2008 list,Sinosteel Corporation,a landmark group of China industries quietly squeezes into the candidate line.As the largest steel service ＆ trade enterprise,its sales reached at RMB 111.24 billion,with a year-on-year increase of 83.03 percent,and the profit grew by 180.03 percent.On the Sinosteel 2008 Work Meeting,the president Huang Tianwen uttered,＂In the coming year,we will work for US$20 billion sales,and look forward to getting a position in Fortune 500 firms for ourselves.＂