Dually sustainable urban mobility option: Shared-taxi operations with electric vehicles

Electric vehicles (EVs) are energy efficient and often presented as a zero-emission transport mode to achieve long-term decarbonization visions in the transport sector. The implementation of a sustainable transportation environment through EV utilization, however, requires the addressing of certain cost and environmental concerns such as limited driving range and battery-charging issues before its full potential can be realized. Nevertheless, a specific type of use of EVs, namely in taxi services, may elicit positive public opinion, as it promises a commitment toward sustainability in urban life. In light of this, this study proposes an integrated approach that combines EV operation with a conceptual design for shared-ride taxi services. As some productivity loss may be naturally expected due to the time spent in charging, it is important to look at whether such performance loss from the passenger and system standpoints can be offset with ingenuity in operational design. In this study, an EV taxi charge-replenishing scheme that can be coupled with a real-time taxi-dispatch algorithm is designed. The proposed EV charging schemes for taxi services are studied via simulations and the effects of the limited driving range and battery-charging details are examined from a system performance viewpoint. The simulation study also reveals illustrative results on the impact of the EV taxi fleet's operation on the charging system. Next, a real-time shared-taxi operation scheme that allows ride sharing with other passengers is proposed to maximize the operational efficiency. The simulation results suggest that the shared-taxi concept can be a viable option to improve on the limitations caused by EV operation. In addition, the importance of projected charging demands and queue delays at different charging locations are also addressed. Some limitations and a future research agenda are also discussed.     

Pareto efficient allocation of an in-motion wireless charging infrastructure for electric vehicles in a multipath network

Electric vehicles (EV) use an eco-friendly technology that limits the greenhouse gas emissions of the transport sector, but the limited battery capacity and the density of the battery are the major barriers to the widespread adoption of EV. To mitigate this, a good method seems to be the innovative wireless charging technology called ‘On-Line EV (OLEV)’, which is a contactless electric power transfer technology. This EV technology has the potential to charge the vehicle’s battery dynamically while the vehicle is in motion. This system helps to reduce not only the size of the battery but also its cost, and it also contributes to extending the driving range before the EV has to stop. The high cost of this technology requires an optimal location of the infrastructure along the route. For this reason, the objective of this paper is to study the problem of the location of the wireless charging infrastructure in a transport network composed of multiple routes between the origin and the destination. To find a strategic solution to this problem, we first and foremost propose a nonlinear integer programming solution to reach a compromise between the cost of the battery, which is related to its capacity, and the cost of installing the power transmitters, while maintaining the quality of the vehicle’s routing. Second, we adapt the multi-objective particle swarm optimization (MPSO) approach to our problem, as the particles were robust in solving nonlinear optimization problems. Since we have a multi-objective problem with two binary variables, we combine the binary and discrete versions of the particle swarm optimization approach with the multi-objective one. The port of Le Havre is presented as a case study to illustrate the proposed methodology. The results are analyzed and discussed in order to point out the efficiency of our resolution method.     

Electrification of a city bus network—An optimization model for cost-effective placing of charging infrastructure and battery sizing of fast-charging electric bus systems

The deployment of battery-powered electric bus systems within the public transportation sector plays an important role in increasing energy efficiency and abating emissions. Rising attention is given to bus systems using fast charging technology. This concept requires a comprehensive infrastructure to equip bus routes with charging stations. The combination of charging infrastructure and bus batteries needs a reliable energy supply to maintain a stable bus operation even under demanding conditions. An efficient layout of the charging infrastructure and an appropriate dimensioning of battery capacity are crucial to minimize the total cost of ownership and to enable an energetically feasible bus operation. In this work, the central issue of jointly optimizing the charging infrastructure and battery capacity is described by a capacitated set covering problem. A mixed-integer linear optimization model is developed to determine the minimum number and location of required charging stations for a bus network as well as the adequate battery capacity for each bus line. The bus energy consumption for each route segment is determined based on individual route, bus type, traffic, and other information. Different scenarios are examined in order to assess the influence of charging power, climate, and changing operating conditions. The findings reveal significant differences in terms of required infrastructure. Moreover, the results highlight a trade-off between battery capacity and charging infrastructure under different operational and infrastructure conditions. This paper addresses upcoming challenges for transport authorities during the electrification process of the bus fleets and sharpens the focus on infrastructural issues related to the fast charging concept.     

重庆“钉子户”事件的物权法分析

重庆"钉子户"事件引起了社会的广泛关注。该事件的产生涉及若干《物权法》上的问题,也反映了目前我国城市房屋拆迁制度存在的缺陷。弥补这些缺陷应在《物权法》中明确界定"公共利益"的范围、确定拆迁补偿的规则,从而进一步完善《物权法》中的征收制度。     

浅谈高校收费的管理和收费制度的建立

从我国高校收费的由来至目前高校收费及其管理现状到高校收费管理制度的改革和建议,浅议了在实行高等教育全面收费制度的今天,如何加强高校收费管理,制止各种乱收费现象,并尝试构建切实可行的高校收费管理制度.     

Socially optimal replacement of conventional with electric vehicles for the US household fleet

In this study, a framework is proposed for minimizing the societal cost of replacing gas-powered household passenger cars with battery electric ones (BEVs). The societal cost consists of operational costs of heterogeneous driving patterns' cars, government investments for charging deployment, and monetized environmental externalities. The optimization framework determines the timeframe needed for conventional vehicles to be replaced with BEVs. It also determines the BEVs driving range during the planning timeframe, as well as the density of public chargers deployed on a linear transportation network over time. We leverage data sets that represent US household driving patterns, as well as the automobile and the energy markets, to apply the model. Results indicate that it takes 8 years for 80% of our conventional vehicle sample to be replaced with electric vehicles, under the base case scenario. The socially optimal all-electric driving range is 204 miles, with chargers placed every 172 miles on a linear corridor. All public chargers should be deployed at the beginning of the planning horizon to achieve greater savings over the years. Sensitivity analysis reveals that the timeframe for the socially optimal conversion of 80% of the sample varies from 6 to 12 years. The optimal decision variables are sensitive to battery pack and vehicle body cost, gasoline cost, the discount rate, and conventional vehicles' fuel economy. Faster conventional vehicle replacement is achieved when the gasoline cost increases, electricity cost decreases, and battery packs become cheaper over the years.     

治理交通拥堵要从加强停车收费管理破题——对吉安市中心城区机动车停放及收费管理情况的调查

随着社会经济的发展,城市居民生活水平的提高,吉安市中心城区机动车保有量不断攀升,停车难、停车乱、停车收费不规范成为社会关注的热点。为了加强机动车收费管理,利用价格杠杆改善停车条件,规范交通秩序,吉安市物价局组织力量对市中心城区机动车停放及收费情况进行了调研,在了解机动车停车场建设、停车收费管理现状的基础上,分析了停车收费管理中存在的问题,提出了解决问题的建议。     

气垫带式输送机的优化设计

简单介绍了粮食仓储气垫带式输送机的优化设计。     

Airport Services and Airport Charging Systems: A Critical Review of The EU Common Framework

This paper reviews proposals contained in the Commission of the European Communities (CEC) Consultation Paper of 1995 and Draft Directive of 1997 on Airport Charges. Economic and practical problems associated with the CEC proposals are highlighted. The main conclusions are that the CEC proposals will be difficult to enforce because they are vague, implementation is left to the individual member states, and because they allow for a variety of approaches to charging systems which can include substantial cross-subsidisation across aeronautical and non-aeronautical uses at one or more airports. The fact that the Commission will not have significant powers of enforcement further reduces the impact which the proposals can have.     

ASSESSING CAPITAL CHARGING IN THE NATIONAL HEALTH SERVICE

Capital charging was introduced into the NHS in 1991, as one of the components of the internal market reforms. Having established context and rationale, this article reviews published surveys of capital charging. It then reports the results of a questionnaire survey conducted in 1994 which probed the views of finance and estates staff in NHS provider units in Scotland as to the efficacy and effects ofcapital charging. Strong support for the principle of capital charging was found, despite considerable evidence of implementation difficulties which had differentially impacted upon Health Boards. Respondents expected that the effects of capital charging would be lower investment and higher disposals, thus leading to a smaller NHS estate.