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581.
ABSTRACT This paper studies incentive-based subsidy to transit systems to improve performance. It derives a formula for optimal effort that equalizes marginal cost and marginal benefit and derives some principles from it among which is that the larger the value of a transit system’s performance criterion the larger the effort it will exert to improve it. Next, using a constrained cost minimization approach it derives a nonlinear cost function that includes optimal effort and estimates it using an unbalanced panel data of single mode U.S. bus transit systems. The results show that optimal effort is the equivalent of seven full-time employees (15,243 labor hours) per year and in real terms it results in 0.6% cost saving (US$198,331) and US$836,796 in incentive subsidy per observation. The implications of these findings are examined. 相似文献
582.
Bicycle sharing systems (BSS) have increased in number rapidly since 2007. The potential benefits of BSS, mainly sustainability, health and equity, have encouraged their adoption through support and promotion by mayors in Europe and North America alike. In most cases municipal governments desire their BSS to be successful and, with few exceptions, state them as being so. New technological improvements have dramatically simplified the use and enforcement of bicycle return, resulting in the widespread adoption of BSS. Unfortunately little evaluation of the effectiveness of differently distributed and managed BSS has taken place. Comparing BSS systems quantitatively is challenging due to the limited data made available. The metrics of success presented by municipalities are often too general or incomparable to others making relative evaluations of BSS success arduous. This paper presents multiple methodologies allowing the estimation of the number of daily trips, the most significant measure of BSS usage, based on data that is commonly available, the number of bicycles available at a station over time. Results provide model coefficients as well as trip count estimates for select cities. Of four spatial and temporal aggregate models the day level aggregation is found to be most effective for estimation. In addition to trip estimation this work provides a rigorous formalization of station level data and the ability to distinguish spatio-temporal rebalancing quantities as well as new characteristics of BSS station use. 相似文献
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王庆云 《交通运输系统工程与信息》2019,19(6):1-5
交通运输与技术是需要深入探究的系统工程问题. 从技术与经济发展关系的角度入手,解读了新技术的应用与交通运输发展的关系;系统分析了交通运输中的技术、技术含量、技术含量判断方法等,指出新技术的应用要以提高运输效率和质量为目的;从系统工程的角度分析,得出交通运输系统的关键技术主要体现在交通基础设施、运输工具、装载设备、运输组织管理和服务水平等5个方面.最后简要介绍了交通运输领域部分新技术的应用情况. 相似文献
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基于模糊逻辑的天文定位中选星方式的建模与分析 总被引:1,自引:0,他引:1
基于模糊逻辑的方法,以天体的星等、高度和方位为主要依据,给出选星的模型;进而利用最小二乘法原理对多天体定位的误差进行处理。实验数据验证了该方法是合理有效的。 相似文献
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The paper reviews the current situation on-board microprocessor applications. It first describes the aspects of vehicle technology and performance that are the focus for on-board computing equipment, from engine management systems through to fully intergrated driver decision support. In the second section a wider perspective is taken by examining the interaction of the vehicle and its environment. The third and final section of the paper considers elements of communication which permit extensive transmission of vehicle and journey data for public and private use. The conclusion identifies factors which will influence the speed with which further applications will be adopted. 相似文献
590.
张尊 《交通部上海船舶运输科学研究所学报》1990,13(2):67-76
本文参照思维逻辑的基本原理,分析了专家们加权的过程,找出了专家们加权的机理,用模糊数学方法,建立了模拟专家们加权过程的数学模型,并用C语言使之在微机上得以实现。此外,本文还根据专家系统的基本思想,对指标的选择问题进行了初步探讨,用PROLOG语言将专家们的知识表达出来,再用接口技术将两门语言连接起来,构成了完整的程序——INDEX。本文最后以南京—香港航线上的散装水泥船为例,用INDEX程序进行运算,选出了指标和它们的加权数,基本上解决了指标的选择和加权问题。 相似文献