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841.
842.
本文阐述了企业文化的形成、内涵、个性及表达方式方面的特点,说明了企业文化的作用,同时结合中铁隧道集团公司的企业文化的创建,阐述了如何创建优良的企业文化。 相似文献
843.
SHIDong-yan QIUChang-hua XUEJun-fang HUANGMei 《船舶与海洋工程学报》2005,4(1):65-70
In the conceptual stage the function design process is realized by the computer aided application. After surveying on the function specification methods and the function modeling, a computer aided function design environment is analyzed. Subsequently based on a module library and principle catalogue, a solution finding process as a part of conceptual design is proposed for a creative design. In addition, a search algorithm to find the solution of adaptable function structure is also discussed. The concepts proposed in this paper can support the subsequent design stages, especially simulation for checking the function structure defects. 相似文献
844.
回顾运输管理信息系统(TMIS)建设的10年奋斗历程,简明扼要地介绍TMIS实现的功能,并畅想了铁路运输管理信息系统的发展方向. 相似文献
845.
Projecting future traffic is an important stage in any traffic and transportation planning study. Accurate traffic forecasting is vital for transportation planning, highway safety evaluation, traffic operations analysis, and geometric and pavement design among others. In view of its importance, this paper introduces a regression-based traffic forecasting methodology for a one dimensional capacity-constrained highway. Five different prediction functions are tested; the best was selected according to the accuracy of projections against historical traffic data. The three-parameter logistic function produced more accurate projections compared to other functions tested when highway capacity constraints were taken into consideration. The R 2 values at various test locations ranged from 88% to 98%, indicating good prediction capability. Using the Fisher's information matrix approach, the t-statistic test showed all parameters in the logistic function were highly statistically significant. To evaluate reliability of projections, predictive intervals were calculated at a 95% level of confidence. Predictions using the logistic function were also compared to those predicted using the compound growth rate and linear regression methods. The results show that the proposed methodology generates much more reasonable projections than current practices. 相似文献
846.
ABSTRACT In this paper we focus on the estimation of crowding in public transport – specifically urban rail systems – and its effect on perceived comfort. It is different from similar studies in the method it employs for estimating crowding levels in vehicles. Specifically, we formulate a function of time and location, which uses only passenger embarking data to estimate the number of passengers in vehicles. Then we convert the estimated crowding values into perceived discomfort levels by trip section. Our method depends on hourly seasonality assumptions but provides good estimates of crowding in urban rail systems even when passenger alighting data is not available. We illustrate the implementation of our model with the example of the Istanbul Metro system. 相似文献
847.
848.
为摆脱基于地理位置划分和建筑物分类标准来确定建筑物停车配建指标的局限,切实改善建筑物停车配建容易出现的不适应状态,增强停车配建的内稳性,采用本体论的理念,从停车配建的内在特征入手,对泊位功能进行划分,并结合区位条件属性的分析来修正已有停车配建标准,建立基于泊位功能划分和区位条件的停车配建方法,最后用实例对该方法进行了比较验证。结果表明:基于泊位功能划分和区位条件的停车配建方法更能反映建筑物的具体环境条件,符合区域规划战略的实际要求,适应交通环境的较大变化范围,可获得比较有效的配建指标,并具有良好的操作性。 相似文献
849.
以某顶推施工独塔斜拉桥钢箱梁为背景,在斜拉桥各种设计理论的基础上,提出了一种更适合于钢箱梁斜拉桥的索力优化方法。采用最小弯曲能量法初定成桥状态,力平衡法确定主梁的弯矩可行域,作为进一步约束优化的约束条件,从而得到斜拉桥各部件受力合理的成桥状态。 相似文献
850.