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31.
Analysing the impact of urban policy interventions on urban growth, land use and transport (LUT) is crucial for urban planners, transport planners and policy-makers, especially in rapidly growing cities. This paper presents a cellular automata-based land-use/transport interaction model – Metronamica-LUTI – for Jeddah that is used to analyse the impact of different proposed policy interventions under two urban growth scenarios for the period 2011–2031. Used as an integrated policy impact assessment tool, the model demonstrates a strong reciprocal relationship between LUT in Jeddah. This study shows that relevant spatial information and integrated policy impact assessment can provide rich insights into the interaction between LUT, the appropriate policy to consider in place and time which traditional planning practice and typical static urban models cannot do.  相似文献   
32.
Beach “nourishment” consists of placing sand on an eroding beach. The widened beach provides increased storm protection to adjacent structures and improved recreational benefits, but is most often transient, requiring on-going, repeated nourishment episodes. Numerical models of beach nourishment typically address such questions as how long a widened beach will last; economic models compare the benefits and costs of preserving a stretch of beach without regard to its geomorphic evolution. Neither have addressed the physical nor economic interactions between adjacent nourishing communities. Here, we couple a numerical model of coastline evolution and a cost-benefit model of beach nourishment, allowing adjacent communities to make dynamic nourishment decisions. Beach nourishment benefits adjacent communities both “updrift” and “downdrift.” The total amount of money spent on nourishment activities can decrease by as much as 25% when adjacent communities both conduct on-going nourishment projects, as opposed to the case where each community nourishes in isolation.  相似文献   
33.
This paper investigates the open water performance of the Ka-series propellers at various pitch and expanded area ratios in combination with the 19A duct by employing the panel method panMARE and the RANSE code ANSYS-CFX. An efficient method, Caly, is developed in order to generate the 3D-geometry and the surface numerical grid of the ducted propellers. Caly can be coupled with ANSYS-TurboGrid to automatically produce 3D-grids for the RANSE solver. The numerical results are compared with published experimental data and the flow details are concluded and compared. The influences that the grid resolution, the panel arrangements of duct and blade, and the flow in gap between inside wall of the duct and blade tip on the numerical results are studied. Grids verification, turbulence model dependency analysis and Reynolds number scantling are also discussed.  相似文献   
34.
ABSTRACT

This paper describes a method to analyse and evaluate different trajectory planning methods and controller types for usage in automated vehicles. Its application is shown by using a novel trajectory planning approach considering comfort aspects (based on Rapidly Exploring Random Tree (RRT)), two different controllers to follow the planned path (cascade controller and flatness based controller) and a simulation method to obtain resulting lateral vehicle accelerations. The method is used to plan and drive a trajectory through a roundabout. It can be seen that the lateral accelerations of the controller-driven vehicle are in the range of the values used for planning. However, the results of both controllers show differences in lateral deviation and in smoothness of lateral accelerations. The simulation results are then compared to real-world test drives in the same roundabout. The measured lateral accelerations are in the same range as well but show a smoother progression than the two controller models.  相似文献   
35.
The paper describes some of the key issues that need to be addressed in the design and execution of underground structures to ensure their long term suitability as watertight units and outlines through practical examples of structures that have not achieved their design requirements which situations need to be considered. Waterproofing is not an exact science but a combination of theoretical knowledge and practical experience based on the five key factors: Environment, Design, Materials, Application and Use of the Structure.In conclusion the paper outlines the advances in crack control to date that can provide the necessary long term guarantees.The adoption of re - injectable crack inducers permitted the Client to save over 10% on construction costs and reduced the construction time by six months.  相似文献   
36.
The impact of new technologies has been mostly under-estimated in the past and, as a result, the transitions from one era to another have occurred more or less by chance. The MANTO research project is intended to avoid mischances. So it indicates potential developments in the telecommunications sector and, in particular, investigates their effects upon transport and settlement and also upon society, the economy and the environment. Nevertheless, MANTO does not merely take a look at the future, like the Greek oracle from whom it takes its name; by means of concrete recommendations, MANTO is intended to provide persons in responsible positions with a tool with which they can consciously organise that future. Risky developments are to be precluded in advance while desirable consequences are to be promoted. Explanation of the used term: MANTO was the daughter of the famous prophet Teiresios of Theben and a seer herself too. As a (German) abbreviation MANTO also stands for: human being (Mensch), offer (Angebot) and needs (Nachfrage) for transportation and telecommunication (Transport und Telekommunikation), considering economy and ecology (Oekonomie und Oekologie).  相似文献   
37.
The measurement of accessibility: Some preliminary results   总被引:4,自引:0,他引:4  
This paper presents an analysis of accessibility by private transport, using a Hansen type measure of accessibility. The data base is the 1962 London Travel Survey. The study is confined to car-owning households residing in inner London. A comparison of the patterns of accessibility associated with four measures of areal attractiveness - total employment, retail employment, households and population - is presented. The sensitivity of relative accessibilities to marginal changes in parameter values is analysed. Two aspects of the effect of the zoning system on the measurement of accessibility are investigated: the effects of zonal configuration and zonal aggregation. First, the implications of increasing the size of central area zones is analysed. Second, a comparison of patterns of accessibility calculated at the zonal and district levels is undertaken.[/p]  相似文献   
38.
2006年4月27日,由中国船东协会与中远集团共同主办的“航运市场与企业成长”论坛正式开幕。期间,美国联邦海事委员会主席史蒂文&;#183;布拉斯特先生,中国交通部水运司副司长张守国先生,中国钢铁工业协会副秘书长戚向东先生,英国克拉克森航运咨询公司董事总经理马丁&;#183;斯托普福德先生,美世管理顾问公司董事、合伙人曾伟民先生,中远散贷运输有限公司总经理张良先生,莱德系统公司副总裁兼中国区总经理克里斯托弗&;#183;伍德沃先生分别进行了精彩演讲,本文即为马丁&;#183;斯托普福德先生对国际集装箱班轮运输市场的展望。  相似文献   
39.
Smart card automated fare payment systems are being adopted by transit agencies around the world. The data-storage characteristics of smart cards present novel opportunities to enhance transit services. On the one hand, there are fare policies, where smart card holders are given specific rebates on the use of the service based on usage patterns or levels. On the other, there are non-fare policies, for instance if holders receive advantages, such as rebates and offers, from commercial partners. The purpose of this paper is to present a geodemographic framework to identify potential commercial partnerships that could exploit the characteristics of smart cards. The framework is demonstrated using data from Montreal, Canada. Household survey data, specifically trip ends, and business data points are jointly used to determine the exposure of various types of establishments to users of the Montreal Metro network. Spatial analysis of business establishments in the neighborhood of metro stations helps to identify potential commercial partners. The results illustrate the potential of geodemographic analysis to generate intelligence of commercial interest.  相似文献   
40.
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