街谷空气污染研究评述及城市规划应对框架

对城市街道峡谷(街谷)空气污染领域的研究现状、发展趋势和存在问题进行分析。以科学问题的内涵和结构为基础,提出街谷空气污染问题的求解应答域及街谷空气污染防治未来所需研究的主要内容。根据公共安全管理的生命周期理论,建立"污染源管控、扩散途径优化、污染受体保护"的街谷空气污染防治策略,设计由街谷污染机制、风险预警与防治模型、规划设计与管理、信息支持平台等共同构成的科学行动框架。在城市环境问题突出的背景下,街谷空气污染防治的城市规划对策研究是对城市问题中关键领域的重要问题的积极应对。     

Cost-effectiveness of air pollution abatement in Poland

The aim of the paper is to discuss the concept of cost-effectiveness of national air pollution abatement programmes, analyze it from a region-wide perspective, and outline a framework for integrating international and domestic environmental priorities. The paper refers to air protection policy priorities adopted by the government of Poland in 1990, and reviews policy instruments envisaged for their implementation. Additionally, it discusses international priorities and how the government of Poland attempts to address these in its policy.After defining cost-effectiveness, this paper reviews how the choice of policy instruments influences the costs of pollution control policy. Then, the recent Polish experience with charges, environmental funds, and transferable permits is confronted with the cost-effectiveness principles. The paper concludes that Poland has developed an extensive system of pollution fees which serves a revenue-raising purpose and gives modest incentives to abate, although the cost-effectiveness of this mechanism needs improvement. A potential role for transferable permits is emphasized.     

城市的经济发展水平影响空气质量吗——基于中国31个省会城市和直辖市的经验验证

基于库茨涅兹曲线,并考虑到各城市的内生因素的影响,研究我国的经济发展水平和空气质量的关系,实证结果显示,我国省会城市、直辖市的曲线只存在库茨涅兹曲线拐点后面的部分,且倾斜程度十分微小,即表明近十年内,我国省会城市、直辖市的空气质量随着经济的发展,得到一定程度的改善,但是改善程度十分有限,城市的经济发展水平对其空气质量水平并不具有决定性作用,影响城市空气质量的最主要因素来自城市自身及其周边地区的工业排放物。     

我国外国航空运输业营业税征管现状与思考

本文以北京市地方税务局涉外税务分局所管辖的外国航空运输公司为例,从税收协定和税收政策方面分析我国税务机关在对外国航空运输业营业税征管中存在的问题,并针对问题提出建议。     

浅析美国空军ATE和TPS管理

本文讨论了美军空军自动测试设备(ATE)和测试程序集(TPS)管理政策,探讨美国空军采取的如何提高保障能力和缩减保障费用的措施。他们出台ATE和TPS政策的目的明确:一是减少针对特定武器系统的专用自动测试系统开发,提高通用化;二是利用新技术提高TPS的标准化和降低全寿命周期内的费用。     

Intermodal integration in air transportation: status quo, motives and future developments

Soaring air traffic, increasing urban expansion and airports operating at full capacity are reasons that have caused a discussion about improvements in airport landside access systems. One approach to better match customer demands and address airport congestion is to facilitate the intermodal integration of airports. Building on a survey on intermodal passenger air transportation, we elaborate on the current and future situation at major airports. Our findings indicate a high modal concentration and dependence on individual access modes. However, while airport managers intend to reduce the share of these modes, they plan to increase that of high-occupancy airport access modes. We analyze the underlying motives that cause airports to extend their connections to surface infrastructure. In a case study, we assess an intermodal best practice solution for the integration of air and rail.     

Study of the topology and robustness of airline route networks from the complex network approach: a survey and research agenda

Communication via air routes is an important issue in a world organized around a web city network. In this context, the robustness of network infrastructures, e.g. air transport networks, are a central issue in transport geography. Disruption of communication links by intentional causes (e.g., terrorist attack on an airport) or unintentional (e.g., weather inclemency) could be crucial for countries, regions and even the airlines affected themselves. Policymakers and the management of airlines and alliances should be able to reduce the effects of such interruptions in order to ensure good communication through air transport (i.e., maximize the robustness of their network at a reasonable cost). The literature review of the study of air transport route networks through an analysis of complex networks has highlighted a lack of contributions to the study of the topology and the robustness of such networks which contrasts, with advances undertaken for other transport networks or communication systems. This survey suggests areas in which research should be undertaken, based on the existing literature in other areas and from three different perspectives: global route networks, airline alliances, airlines and airports so as to help towards a better understanding of air traffic and, therefore, to be able to assess the potential damage of any airport being inoperative for a continent, country or airline.     

The potential of horizontal collaboration in airport ground freight services

Since the global economic crisis of 2007–2011, the increasingly dynamic and challenging air cargo market in Europe has forced freight forwarders to improve their performance. In addition to improving their internal transport efficiency, they have also started to look at previously unexplored opportunities for horizontal collaboration in landside airport transport. The aim of this study is to reveal the potential of air cargo transport collaboration on a horizontal level, i.e. between multiple freight forwarders within a single airport. Reviewing existing literature on horizontal collaboration, with a focus on the air cargo industry, we propose a conceptual framework for transport collaboration in the air cargo industry. Based on a comprehensive study on air cargo transport movements within Schiphol, using a simulation model based on company data of 10,747 shipments (6977 tons of cargo) for a period of 30 days, we find several interesting results. Our main finding is that horizontal collaboration can improve the transport performance, by maintaining a high frequency of transport movements and maintaining an acceptable throughput time for air cargo shipments, and at the same time reduce transport costs by up to 40%. For smaller freight forwarders, the frequency of transport deliveries can even increase, while still allowing them to improve the average load factor of transport movements.     

A novel heuristic approach for solving aircraft landing problem with single runway

Nowadays, airlines administrations are more willing to utilize optimization tools to control air traffic due to considerable increases in volume of air transports. A challenging problem in the field of air traffic is how to optimally schedule landing time of aircrafts and assign them to different runways such that early and late landing costs are minimized. This problem is called aircraft landing problem (ALP). This paper proposes a novel decomposition based heuristic by solving two sub-problems for the ALP with single runway. In the first sub-problem, we apply the adaptive large neighborhood search (ALNS) algorithm to find a sequence of aircrafts. The solution found in the first sub-problem will be sent to the second sub-problem, to check for the feasibility of the solution using CPLEX solver. A set of benchmark problem are taken from the OR library for the purpose of comparison with other existing approaches. The computational results exhibit that the proposed algorithm is capable of finding the best known optimal solution for all the instances.     

Searching for the sweet spot: The determinants of direct services from Canadian airports

In markets for scheduled passenger travel services, demand may be not independent of supply. On airline routes the speed, convenience and frequency of services affect demand along with price and other economic factors. This generates the possibility of multiple equilibria. For 185 domestic Canada and trans-border city-pair routes, of which 101 currently lack non-stop service, we find that twelve of the latter (all trans-border routes) have a “sweet spot” – although current passenger numbers do not justify non-stop service, were this to be introduced, it would turn out to be economically justified by the boost in the attractiveness of the route.