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91.
Higgins  Thomas J. 《Transportation》1985,12(4):343-359
The author examines new, flexible parking requirements in several U.S. cities and Canada. Flexible requirements provide relaxations in zoning code specifications for off-street parking in return for developer commitments to ridesharing measures, support of transit or in-lieu fees for public parking. Issues examined include whether developers take advantage of flexible requirements, whether agreements with developers lead to agreed-upon action, and whether actions lead to desired results. Based on experiences of several cities, implications and cautions are drawn for local planners. The first caution relates to cities using flexible requirements to collect in-lieu fees in support of public parking. Where cities delay providing parking, inflation may make it difficult to provide the desired parking supply. Or, developers may not choose to pay the fee, such as in the case where cities grant relaxations for other measures more attractive than paying the fees.Other implications relate to flexible requirements in support of ridesharing or transit. Developers will not necessarily take advantage of relaxations tied to support of these modes. Generally, developers will take the least-cost ways to gain relaxations. They may choose to provide the parking where transit or ridesharing measures are too costly or complex. Or, they may take relaxations easier to obtain than those for ridesharing and transit. Finally, even where developers do agree to ridesharing measures, the measures may not be effective. On the other hand, developer-sponsored actions have proven effective in some cities where tight or expensive parking prevails, or where neighborhood residents have organized against office commuters parking on neighborhood streets, or where other economic or community variables favor ridesharing and transit.  相似文献   
92.
This paper analyzes the complex interdependencies between residential relocation and daily travel behavior by focusing on modal change. To help explain changes in daily travel patterns after a long distance move between cities the concept of urban mobility cultures is introduced. This comprehensive approach integrates objective and subjective elements of urban mobility, such as urban form and socio-economics on the one hand, and lifestyle orientations and mode preferences on the other, within one socio-technical framework. Empirically, the study is based on a survey conducted among people who recently moved between the German cities Bremen, Hamburg and the Ruhr area. Bivariate analyses and linear multiple regression models are applied to analyze changes in car, rail-based and bicycle travel. This is done by integrating variables that account for urban mobility cultures and controlling for urban form, residential preferences and socio-demographics. A central finding of this study is, that changes in the use of the car and rail-based travel are much more dependent on local scale, such as neighborhood type and residential preferences, whereas cycling is more affected by city-wide attributes, which we addressed as mobility culture elements.  相似文献   
93.
A modelling system for coupled physical–biogeochemical simulations in the water column is presented here. The physical model component allows for a number of different statistical turbulence closure schemes, ranging from simple algebraic closures to two-equation turbulence models with algebraic second-moment closures. The biogeochemical module consists of models which are based on a number of state variables represented by their ensemble averaged concentrations. Specific biogeochemical models may range from simple NPZ (nutrient–phytoplankton–zooplankton) to complex ecosystem models. Recently developed modified Patankar solvers for ordinary differential equations allow for stable discretisations of the production and destruction terms guaranteeing conservative and non-negative solutions. The increased stability of these new solvers over explicit solvers is demonstrated for a plankton spring bloom simulation. The model system is applied to marine ecosystem dynamics the Northern North Sea and the Central Gotland Sea. Two different biogeochemical models are applied, a conservative nitrogen-based model to the North Sea, and a more complex model including an oxygen equation to the Baltic Sea, allowing for the reproduction of chemical processes under anoxic conditions. For both applications, earlier model results obtained with slightly different model setups could be basically reproduced. It became however clear that the choice for ecosystem model parameters such as maximum phytoplankton growth rates does strongly depend on the physical model parameters (such as turbulence closure models or external forcing).  相似文献   
94.
在航运物流链中,所有的货物都要经由海运码头。不管海铁联运,还是海运-卡车联运,或是海上转运,码头都是货物运输的中转站。海运码头运营商(以下简称为MTO)的运营对货物运输影响巨大。  相似文献   
95.
Abstract

The history of urban traffic control (UTC) throughout the past century has been a continued race to keep pace with ever more complex policy objectives and consistently increasing vehicle demand. Many benefits can be observed from an efficient UTC system, such as reduced congestion, increased economic efficiency and improved road safety and air quality.

There have been significant advances in vehicle detection and communication technologies which have enabled a series of step changes in the capabilities of UTC systems, from early (fixed time) signal plans to modern integrated systems. A variety of UTC systems have been implemented throughout the world, each with individual strengths and weaknesses; this paper seeks to compare the leading commercial systems (and some less well known systems) to highlight the key characteristics and differences before assessing whether the current UTC systems are capable of meeting modern transport policy obligations and desires.

This paper then moves on to consider current and future transport policy and the technological landscape in which UTC will need to operate over the coming decades, where technological advancements are expected to move UTC from an era of limited data availability to an era of data abundance.  相似文献   
96.
Abstract

In an efficient transportation system, traffic safety is an important issue and it is influenced by many factors. In a country like Iran, until now safety improvements are mainly concentrated on road engineering activities, without much attention for vehicle technology or driving behaviour. One important aspect of road safety engineering activities is the so‐called treatment of hotspots or dangerous accident locations. Until recently, accident hotspots were identified and remedied by the esxperts’ personal judgements and a handful of statistics without taking into account other important factors such as geometric and traffic conditions of the road network. This paper therefore aims to define and identify the criteria for accident hotspots, then giving a value to each criterion in order to develop a model to prioritize accident hotspots when traffic accident data is not available. To do this, the ‘Delphi’ method has been adopted and a prioritization model is produced by the use of a ‘Multiple Criteria Decision‐Making’ method. The procedure is illustrated on a collection of 20 road sections in Iran. In addition, the model is validated against an existing database of road sections containing safe locations and hotspots. Finally, a sensitivity analysis is carried out on the proposed method.  相似文献   
97.
Abstract

Public transport policy in the Madrid Metropolitan Area is often deemed as a success. In 1985, an important reform was carried out in order to create a new administrative authority to coordinate all public transport modes and establish a single fare for all of them. This reform prompted a huge growth in public transport usage, even though it reduced the funding coverage ratio of the transport system. Since then, Madrid’s public transport system has been undergoing an increasing level of subsidization, which might jeopardize the financial viability of the city public transport system in the future. In this paper, we present a detailed analysis of the evolution of the public transport funding policy in Madrid in recent years. We found that the increasing level of subsidy can hardly be explained on the basis of equity issues. Moreover, we claim that there is still room for a funding policy that makes the efficiency of the system compatible with its financial sustainability.  相似文献   
98.
这是库布齐     
酊然  Tom 《汽车生活》2009,(6):66-75
Jeep Wrangler共3部,Sahara长短版本各一,主角是Rubicon,由它们去挑衅中国第7大沙漠:内蒙古库布齐——去征服和嬉戏。  相似文献   
99.
迷幻公园     
Sonnet  Tom 《汽车生活》2009,(10):20-27
看过Nick Hornby在2007年写的Slam(砰!),才刚16岁的玩板少年Sam,意外地使初恋女友怀孕,简直崩溃。单亲妈妈生下他时才17岁,十足少女母亲,现在这位老妈刚刚32岁,仍然美丽诱人。要是你的哥们儿叫你喝酒都顺便邀请你老妈,你说你会不会很窘?  相似文献   
100.
The Paris Memorandum of Understanding (Paris MoU) has defined criteria aimed at better targeting of ships for Port State Control inspections. These criteria are mostly based on ship detentions or deficiencies. Another approach proposed in this paper is based on the concept of risk, combining in various ways the probability of the occurrence of casualties and the potential consequences of such occurrences. These measures are to help identify High Risk Vessels (HRV) and to inspect them accordingly.  相似文献   
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