共查询到20条相似文献,搜索用时 93 毫秒
1.
《运输经理世界》编辑部 《运输经理世界》2009,(1):4-4
盘点起伏跌宕的2008年.可谓悲喜交加。从年初抗冰雪保畅通到汶川大地震.应急运输接受超强度考验,从奥运火炬传递到北京奥运会、残奥会成功举办,运输保障队伍成功集结并奏响凯歌.从金融危机大网笼罩物流业,到群体群策应激反应……本刊力求忠实全面地记录下所有大事,给行业留下难忘的记忆。 相似文献
2.
基于金属磁记忆的智能清管器技术可行性研究 总被引:2,自引:0,他引:2
文中对基于金属磁记忆的智能清管器用于管道腐蚀检测的可行性进行探讨,介绍了金属磁记忆检测原理,以MSP430F149单片机为核心,采用HMC1021型磁阻传感器为探头,设计了漏磁场检测系统,对裸采和透过聚氨酯材料检测到的漏磁场法向分量HP(Y)的过零点以及最大梯度值进行了分析、计算.结果表明:透过一定厚度聚氨酯材料检测到的裂缝附近漏磁场法向分量HP(Y)的梯度值已不再突出,但微分值仍具有明显的特征.因此,基于金属磁记忆的智能清管器技术具有一定的可行性. 相似文献
3.
60后:快乐的牛拉车与满城的黄色面的
提到童年时代印象最深的交通工具,家在辽宁抚顺的张捷(化名)毫不犹豫的选择了牛拉车."那时候村里没有公路,最宽的路就是村民集体修的用来送粪的牛车路,更没见过汽车,村里送粪用的牛拉车是我见过的第一辆车.那可是我们小男孩眼中的宝贝."说起关于牛拉车的记忆,张捷眼中还有着儿时的兴奋. 相似文献
4.
5.
6.
7.
8.
“没活儿着急,有活儿着急,出了交通事故更着急!“初次见面,北京和众奥顺达物流有限公司董事长宋少波用这样三个短句道出了我国物流人这些年来的尴尬境地。对于已在运输这个行业摸爬滚打二十载的宋少波先生而言,这样的总结中暗含着丝丝苦涩记忆.蕴藏着缕缕心酸往事.更透露出隐隐无奈之情。 相似文献
9.
10.
11.
Pedestrians as compared to vehicular traffic enjoy a high degree freedom of movement even in heavily congested areas. Consequently, there are more alternative links available to pedestrians between a given origin‐destination (O‐D) pair. This paper describes a study done by the University of Calgary to evaluate the factors affecting the choice of route on intra‐CBD trips or trips within the Central Business District (CBD). An origin destination survey conducted in downtown Calgary, Alberta enabled the identification of the most significant factors influencing the choice. These factors were analyzed in relation to the physical characteristics of the location, personal characteristics of the trip maker and the type of the trip. It appears that most people chose the shortest link and factors such as the level of congestion, safety or visual attractions were only secondary. This suggests that the length should be made a major consideration when planning and designing pedestrian links. 相似文献
12.
13.
《Transportation Research Part A: General》1991,25(6):407-418
The main deficiency of most current modeling approaches to transportation can be identified as neglect of the integration of existing geographical knowledge in regard to the ex ante transport/land use modeling approaches, with its focus on territorial dynamics and theory development. This paper addresses this aspect of the problem by introducing a theoretical and methodological framework for the analysis of the interrelationship between land uses. The analysis attempts to determine to what extent the functional land use in a city can be considered an ordered pattern. The order sought does not rely on purely spatial configurations, but on the correlation of transportation and land use. The first section of this paper focuses on theoretical considerations. It stresses the fact that conventional approaches do not apply in the present context. It then suggests an alternative based on areas of influence and measured in terms of level of attractance of land uses. The second describes a procedure based on this alternative following the remarkable contribution of Hanjoul, Beguin and Thill. An application of this procedure to the analysis of Shanghai is then examined. Finally, an evaluation of the strategies for optimizing the interrelationship between land uses is presented. The paper concludes with a possible research agenda. 相似文献
14.
明确埋地管道防腐保温层的技术评价标准,对埋地钢质管道的安全运行,延长管道使用寿命具有重要意义。为了对埋地管道防腐保温层做出有效评价,从间接检测与开挖检测2个方面,结合现场检测数据,提出了基于防腐保温层的电流衰减率、绝缘电阻率、质量状况与厚度的分级评价标准及基于4种评价指标的综合评判方法。工程实践表明,该评价标准对防腐保温层是否存在失效能做出有效判断。 相似文献
15.
介绍了城市轨道交通工程中杂散电流不同的监测系统的构成,分析了集中式、分散式和智能型等监测系统的配置和功能,以及智能型实时在线监测系统的重要意义,为轨道交通工程杂散电流监测系统的选择与应用提供参考。 相似文献
16.
天然气自动计量系统有多种组态软件,由于软件的不相通性,造成了计量系统数据采集的通用性差、数据传输与入库的时效性差、数据利用的可靠性低.结合各组态软件的实际情况,从设计上充分利用Oracle大数据处理能力以及Partition(分区表)的特性,实现历史数据的存储,应用WebService与COM+数据访问组件提供多层数据访问架构,采用OPC与DDE工业数据交换协议,实现了各站场计量数据的实时上传,为连续数据采集和实时监控提供了可能,节约了改造成本. 相似文献
17.
18.
Joseph N. Prashker 《Transportation》1979,8(4):329-346
Reliability of travel modes was found to be the most important characteristic of transportation systems in several attitudinal investigations of individual travel behavior. This paper represents the first part of a research effort aimed at gaining a better understanding of the characteristics of reliability of transportation modes in urban travel. In this research, reliability characteristics are identified; their importance relative to each other is assessed, and an insight into possible structure of an objective reliability index is discussed. The research is based on perceived values of reliability, which were identified through a large attitudinal survey conducted in the Chicago metropolitan area. 相似文献
19.