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921.
922.
Michael W. Hughes 《Engineering Management Journal; EMJ》2013,25(1):9-14
ABSTRACTThe Cassini Project, a NASA-funded exploration mission to Saturn that is being managed by the California Institute of Technology's Jet Propulsion Laboratory for NASA, has developed a distributed project schedule control system for complex development programs. The system is called the Cassini Management Information System (CMIS). The system was built to make schedule control simple, user-friendly, and low-cost. CMIS is distributed across a local area network of PCs and Macintosh computers and consists of four major modules: schedule control, action item tracking, work package implementation plan, and budget tracking. This article focuses on the schedule control module of CMIS. CMIS was one of the innovations introduced in response to the decrees of the U.S. Congress, and subsequently NASA, to conduct space exploration on a fixed-price basis. This article summarizes CMIS development history as a schedule control tool, its key features, and its use by more than 130 engineers and managers. 相似文献
923.
黄美琼 《计算机光盘软件与应用》2012,(2):204-205
本文首先从系统架构、功能模块、数据库进行分析,然后介绍了系统的界面设计和登陆模块、查询模块的详细设计。 相似文献
924.
当前,社会发展进入十三五新时代,以人为本充分体现了对社会生产中劳动力的强烈关注,因此安全生产是企业得以发展的最基础保证。石油企业作为国民经济的支柱产业,但又是高危行业,安全形势十分严峻。因此安全管理成为石油企业急需深入探究的问题。文章分析了石油企业目前在安全管理方面存在的问题,提出了在安全管理上采取的一些方法和措施。 相似文献
925.
作为银行传统业务方式的一种延伸,网上银行的方便、快捷、低成本受到银行和广大用户喜爱,网银的市场交易额每年都有较大的增长。但是,由于互联网的开放性和复杂性,网上银行的广泛应用也给不法分子可乘之机,严重威胁网银用户的个人隐私和资金的安全,研究制定用户使用网络银行安全防范措施,加大网络银行安全防范力度具有重要意义。 相似文献
926.
The City of Edmonton began its intersection safety device (ISD) program in 2009 with the installation of 50 cameras throughout the city. The ISDs are approach-specific and combine automated enforcement of red-light running and speed violations during the red and green phases of the intersection control. The goal of this study is to evaluate the safety performance of ISDs within the city of Edmonton, Canada and to identify factors that can lead to successful selection of future ISD sites. A before-and-after Empirical Bayes (EB) method is used to account for regression-to-the-mean and other confounding factors. A safety performance function and yearly calibration factors are developed using data from a set of reference intersections within Edmonton. The before-and-after analysis is applied at the overall intersection level and for each approach of the ISD intersections. The results showed significant reductions that ranged from 12% to 25% for total collisions, and from 33% to 43% for angle collisions. No significant reduction was observed for severe collisions at the intersection level, however significant reductions were found at the approach level at locations with a relatively higher collision history. The impact of site selection criteria on collision reduction was also evaluated. Greater reductions were found at sites with a higher collision frequency. Additionally, the impact of intersection characteristics on collision reduction was investigated. Speed limits, presence of separated right turn lane and the number of lanes were found to impact ISD collision reduction. 相似文献
927.
The paper analyzes spatial and temporal data on fatal train-pedestrian collisions in the Chicago metropolitan area between 2004 and 2012. In comparing different municipalities within the region, the density of grade crossings and stations is found to increase the frequency of unintentional deaths. However, unintentional deaths do not increase with train volume suggesting that pedestrians may exercise more care around busier lines. The distribution of apparent intentional deaths is less strongly related to the density of crossings and stations suggesting that those intending self-harm will seek out a point of access. Apparent intentional deaths are more prevalent on lines with frequent passenger trains, and in municipalities with higher incomes and lower population densities. While most of the apparent intentional deaths (about 70%) are not associated with any copycat activities, the dataset contains possible clusters of intentional deaths that are proximate in both time and space. There was also a highly publicized suicide that led to a 95% increase in apparent intentional deaths throughout the region in the 18 weeks following the incident. 相似文献
928.
Mensura Junuzovic Patrik Midlöv Sara Larsson Lönn Anders Eriksson 《Accident; analysis and prevention》2013
Since any firearm injury is potentially lethal, it is of great interest to prevent firearm incidents. This study investigated such incidents during hunting and Swedish hunters’ safety behaviour. A 48-item questionnaire was posted to a random sample of 1000 members of the Swedish Association for Hunting and Wildlife Management. The questions considered demographics, hunting experience/hunting habits/safety behaviour/attitudes and experience of careless weapon handling, hunters’ weapons and safety behaviour relating to weapons, health status, firearm incidents and their preventability, and personal comments on the questionnaire. The response rate was almost 50%. The mean age of the responders was 54 years; 5% were females. Almost none (1%) reported hunting under the influence of alcohol. Young age and male sex were positively associated with risk behaviour, although the presence of multiple risk behaviours in the same responder was not common. A very high degree of compliance with Swedish laws regarding weapon storage was reported. One-quarter of the responders had witnessed a firearm incident caused by another hunter, which in most situations did not result in human injury or death. An unsafetied weapon was the most common reported “cause” of these incidents. Experience of a firearm incident was not uncommon and the majority of the responders considered the incident in question to be preventable. This study provides a picture of the possible risk behaviour among hunters and the results suggest that future prevention work should target safer weapon handling. 相似文献
929.
An Eulerian circuit in a directed graph is one of the most fundamental Graph Theory notions. Detecting if a graph G has a unique Eulerian circuit can be done in polynomial time via the BEST theorem by de Bruijn, van Aardenne-Ehrenfest, Smith and Tutte (1941–1951) [15], [16] (involving counting arborescences), or via a tailored characterization by Pevzner, 1989 (involving computing the intersection graph of simple cycles of G), both of which thus rely on overly complex notions for the simpler uniqueness problem.In this paper we give a new linear-time checkable characterization of directed graphs with a unique Eulerian circuit. This is based on a simple condition of when two edges must appear consecutively in all Eulerian circuits, in terms of cut nodes of the underlying undirected graph of G. As a by-product, we can also compute in linear-time all maximal safe walks appearing in all Eulerian circuits, for which Nagarajan and Pop proposed in 2009 [12] a polynomial-time algorithm based on Pevzner characterization. 相似文献
930.
This paper analyses motorcycle educational content in a number of French motorcycle schools on the basis of a naturalistic study of riders’ and trainers’ behaviour. The aim is to specify the situations delivered in motorcycle schools and to study the rider's activity in these situations. The methodology includes ethnographic observation within the motorcycle schools and the longitudinal monitoring of 14 trainee motorcyclists during their initial training. The training situations were described by the combination of audio–visual recordings and interviews data (i.e. concomitant or interruptive verbalization, and self-confrontation data). The results permit to (1) compare the “real” and “official” durations of track and on-road training, (2) characterize the real training situations, (3) describe the preferred forms of instruction, and (4) conduct an in-depth analysis of the situations used during training in traffic. The discussion show, in first, the poverty of the training situations which are based on the repetition of the exercises in the test, and, in second, disparities between the riding situations encountered during training and the demands made by riding in natural traffic. The usefulness and the applications of this type of approach – based on the integration of the rider's point of view notably by self-confrontation interview – for understanding real riding behaviours and how such approaches could supplement vehicle-based data are discussed in a large conclusion. 相似文献