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1.
This article examines the use of inland mined sand and offshore dredged sand for beach nourishment projects in North Carolina, focusing on the question of whether inland mined sand is economically preferential for hot‐spot erosion control. Excavation, processing, and transport costs are presented, and cost efficiencies of hypothetical beach nourishment projects are compared. Cost analyses indicate that inland mined sand is economical for small projects (10,000–50,000 cubic yards), given that a clean sand source can be located within 15 miles of the nourishment site. The two factors primarily influencing per cubic yard costs of inland sand are overland transportation expenses and processing costs. The use of dredged offshore sand is less expensive for large projects (> 100,000 cubic yards) due to the economies of scale affecting dredge mobilization. Large beach nourishment projects in North Carolina will most likely continue to utilize offshore dredged sand.  相似文献   

2.
The livelihood of coastal communities is directly linked to the health of intertidal and marine ecosystems. Coastal zones and marine areas are rapidly changing and highly vulnerable to impacts from climate change, accelerating human development, and over-fishing. Quality of life and the benefits of coastal development can be greatly enhanced, and costs minimized, by projecting and comparing alternative policy outcomes before management decisions are made. This article describes the Marine Integrated Decision Analysis System (MIDAS), an interactive decision support tool designed to assist the users and managers of Belize's system of marine management areas (MMAs) in understanding the interactions among various ecological, socioeconomic, and governance conditions in a spatially explicit manner. MIDAS can simulate and visualize the likely effects of alternative management strategies and therefore provides an important tool for evaluating potential scenarios. We developed two MIDAS modules to address specific threats in Belize –spatial risk resulting from mangrove deforestation in coastal areas and the potential effect of an oil spill off the coast of Belize. Workshops conducted in Belize indicate that diverse user groups such as fishers, tourism operators, and public environmental agencies can successfully utilize MIDAS to understand MMA outcomes, and environmental risks.  相似文献   

3.
The project appraisal method in the Netherlands distinguishes direct effects, indirect distribution effects and indirect generative effects. Transport models are generally available for calculating the benefits of transport projects to travellers as part of the direct effects. The TIGRIS XL model, a Land-Use and Transport Interaction model, adds indirect distribution effects for the housing and labour market, by modelling changes in the spatial distribution of jobs and residents. This paper describes the current TIGRIS XL model and how it can be applied in the evaluation of transport projects. It refers to work done with the TIGRIS XL model to improve the calculation of the direct benefits by applying the so-called ‘logsum’ method. Finally it discusses ideas on how to extend the TIGRIS XL model to address indirect generative effects as well.The current TIGRIS XL model, its integration with the National Model System (the standard tool for the Dutch government to analyse the effects on passenger transport) and basic design principles are the starting point of such an exploration. These design principles include:
an emphasis on detail, both spatial as well as in socio-economic segments, to account for differences in the availability of choice alternatives and in choice behaviour, and to provide impacts by region and socio-economic group;
the requirement that the relationships used rest on an empirical foundation.
The post-processing methods proposed on this paper for the calculation of the direct benefits and indirect generative effects are consistent with these design principles. To calculate the indirect generative effects, a post-processing module is proposed which transforms changes in travel times and land-use into agglomeration effects. These agglomeration effects combine several of the generative effects, like scale economies, an increasing variety of products, labour market matches and knowledge spill-over. The effects of changes in the agglomeration indicator on productivity can be estimated with existing data sources, as was demonstrated in the UK (Graham, 2005).  相似文献   

4.
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   

5.
Shipping projects, as land-based ones, are evaluated by using different measures of merit based on discounted cash flows. The bulk carrying industry, where costs are known better than revenues, adopted the required freight rate (RFR) and its derivative the economic cost of transport (ECT) as its major measures of merit. Shipping is a business exposed to many unforeseen risks. Although many of these risks are beyond the control of the shipowners/operators, they should all be carefully weighed during the process of project selection designed for investment decisions. One such risk is the expropriation of shore-based facilities built by the shipping operator at one or more termini of the maritime distribution channel. The operator has to assess the value and probability of risk and translate them into a premium which he will levy on each unit of goods transported. Adding this premium to the required freight rate together with the inventory holding costs and marine insurance charges will produce the real economic cost of transport.  相似文献   

6.
Land use/transport models and economic assessment   总被引:1,自引:0,他引:1  
This paper discusses the economic assessment of policies using land use/transport models. It argues that conventional forms of assessment focussing only on transport changes can underestimate the economic benefits of a policy. The paper argues that the benefits need to be measured by the changes of prices at the end of a trip and not just by the changes in travel costs. Models that do not estimate the changes of prices at the end of a trip cannot properly assess the impact of a policy.The model used in this paper is based on the MEPLAN software and estimates the location of households and employment and the interaction between them. It also estimates the cost of living for households and the production costs for employment. With these costs, it is possible to calculate the wider economic benefits beyond transport.The paper illustrates the assessment of policies for the Cambridge sub-region involving investment in public transport, orbital highway and congestion charging policies. The results forecast by the model are assessed in terms of the conventional cost-benefit using traveller’s surplus as benefits and compared with a wider assessment measure of compensation variation. It demonstrates that the last measure encompasses the wider benefits associated with transport policies which are not taken into account in conventional cost-benefit analysis.  相似文献   

7.
The 1998 White Paper proposed integration as the solution to Great Britain’s land transport problems. Most commentators agree that this much vaunted New Deal for Transport has been a failure. Yet some ten years later policy papers from bodies such as the Institution of Civil Engineers and the Centre for Cities are still proposing integration as a possible panacea.There are a number of reasons for the failure of integrated transport over the last decade. The first is the failure to define the concept. The second is the failure to operationalise the concept. The third is the lack of an evidence base on the success of integrated transport policies. Evidence is now emerging in Britain on the benefits (and indeed the costs) of some aspects of integrated transport policies. The fourth, and perhaps the most crucial, is the lack of will in terms of politicians, civil servants and the public at large, to adopt the behavioural changes necessary for an integrated transport policy to be successful. A series of organisational and funding changes are proposed that could advance the prospects for integration.  相似文献   

8.
The Northern Sea Route (NSR) has tremendous potential for ocean shipping between Europe and Asia due to the savings from shorter transit time and distance. However, the Arctic area is environmentally vulnerable and thus there is a trade-off between NSR’s impacts on environment vs. its economic benefits, especially when compared with the traditional route, such as through the Suez Canal Route (SCR). This study estimates the market shares of different transport modes and alternative shipping routes for the container transport market between Europe and Asia, and the resulting environmental costs. Our result suggests that NSR can be a viable option under the status quo. However, its environmental costs tend to be higher than SCR due to small ship size and low load factor in the present, thus the development of NSR would lead to worse environment outcomes. If these issues can be resolved, NSR can benefit from lower operational and environmental costs, which will lead to higher market share and social welfare. Otherwise, increased use of NSR may lead to higher total environment costs than the status quo.  相似文献   

9.
A few cities in some of the larger developing countries in Latin America and Asia have made increasing use of multi-year concessions or franchises, competitively awarded to private companies, for construction and operation of urban transport infrastructure and for provision of public transport services. In view of the strong prospective growth of developing-country cities with large transport needs, and the rise in the emerging economies of potential new sources of private capital, it is important to see how effective PPP has so far been in this area. The experience is analyzed principally by thorough comparative review of what has actually happened for some of the main users to date: Bogotá, Santiago, São Paulo, Seoul, and several cities in both China and India. Despite delays and mistakes that have been made in development of most of the projects, the overall results, already delivered and in prospect, are very positive and urban public transport is benefiting substantially, with significant side effects on poorer people's access to work and to services, air pollution levels and road accident rates. The widest and most important advantage of the PPP arrangements, as compared with more conventional short-term contracting, is found to be the innovations, technical and managerial, developed, and, in particular, the mutual capacity building of the countries' private and public sectors and their more effective interaction. The experience in the six countries covered suggests that other developing-country cities may be best assisted to develop sound urban transport PPPs more rapidly through provision of help on chosen items among 7 elements that have proved particularly crucial but sometimes weak in the projects reviewed: Civic consultation systems, Land-use/Transport strategic planning, Land/property market management, Monitoring systems, Progressive policies, Economic regulation, and Public institutional framework for PPPs.  相似文献   

10.
Recent transport sector liberalisation, as well as global economic crisis, is favouring the implementation of transport infrastructure projects through Public–Private Partnerships (PPP). However, there is a debate as to whether PPP schemes are a better option than conventional procurement. To this end, an evaluation framework is proposed, to assess which of these two alternative schemes for transport projects financing is preferable for the public. The proposed framework is complimentary to the Value for Money (VfM) approach and is based on a Multi Criteria Analysis (MCA). The first step is the estimation of the Public Sector Comparator (PSC) for the case of conventional procurement, dealing with construction, maintenance and operation costs revenues, as well as any costs associated with risks undertaken by the public. As for the PPP case, it includes any payments by the public sector and related risks costs. The MCA is then applied only if the PPP is found preferable for the public sector. The latter considers additional impacts, including among others the social attributes of a particular scheme, job creation, environmental impacts and safety and security aspects. The proposed framework was applied to a pilot Bus Rapid Transit (BRT) corridor infrastructure project in the city of Indore, India, in order to demonstrate its validity. The framework and its application could provide useful guidance when considering PPP for a transport project, since it demonstrates in a transparent way the society's attitude towards this project, something that is critical to its acceptance.  相似文献   

11.
Government recently introduced the Transport Law Reform Bill, which if passed by Parliament, will allow foreign vessels to uplift and discharge cargoes and passengers along the coast of New Zealand. Coastal shipping is part of the domestic transport industry, which has benefitted from deregulation and considerable restructuring over the last decade. This paper provides a brief review of the coastal shipping industry in New Zealand and an overview of international cabotage laws. An alternative open coast shipping policy proposed by the New Zealand Shipping Federation, which is based on ‘level playing fields’ principles, is presented. The scope of cost benefit analysis is outlined and the potential costs and the potential costs and benefits of the Government's open coast shipping policy are summarized. Despite the potential costs to New Zealand of an open coast policy appearing to be considerably greater than the potential benefits. Government officials have not undertaken an empirical cost benefit analysis. The paperr concludes that hte clauses of the Transport Law Reform Bill relating to an open coast policy should be withdrawn and a full empirical cost benefit analysis should be undertaken to determine the best coastal shipping policy for New Zealand.  相似文献   

12.
One main theme of European Union’s in transport policy statements has been the increased role of railways in the reducing environmental impacts and costs of transport activity. One option to increase the modal share of rail transport is to utilize the dry port concept, particularly applicable to general cargo. At the Port of Gothenburg (Sweden) use of this concept in combination with rail transport has led to a reduction of CO2 emissions, and lower transport energy costs. The main objective and motivation of this research work are to examine through analytical models, how this same dry port concept could be implemented in the Finnish transportation network, with estimates of the benefits being gained.The research method of this study is macro gravitational models of distribution. Main input data for the models are distances and population in the area. The approach aims to research, how relative transport costs behave by increasing the number of dry port distribution locations. For the actual computation work the authors apply linear integer programming. Based on the results, the authors argue that relative transport costs can decrease considerably by increasing the number of dry ports, up to the level of six locations. This is considerably less than what is the current situation in Sweden. The found solution also differs from Sweden as the fragmented Finnish seaport system enables using numerous seaports instead of one, which further decreases inland transportation distances and volumes considerably. At the same time forthcoming sulphur emission reduction regulation (for sea transports) might impact the transportation network structure by decreasing sea transport and the number of seaports used. This might lead to a further increase in land-based hinterland transport.  相似文献   

13.
The diagnosis for urban transport sustainability depends on the context of different regions worldwide. We focus in this paper on West and North Africa which reveal similarities but also structural differences which are explored further. The importance of paratransit in its various forms is strongly observed in sub-Saharan Africa and to a lesser extent in North Africa. The attempts to regulate and organise this sector have been difficult; one interesting experience in Dakar occurred during a programme of fleet renewal. In parallel it is observed that there are positive but insufficient experiences of public transport authorities in some cities (Dakar, Abidjan) and similar projects postponed in other cities because of the institutional problems. One also observes the constant difficulties of designing sustainable schemes for bus companies. An answer to this crisis has been found in North Africa, through investment in new mass transport systems. However, mass transport projects in West Africa are very weak in comparison. The gap between public transport costs and income levels there remains a major obstacle to sustainable mobility exacerbated by the poverty of a significant part of the urban population in West Africa. Two other critical factors are also identified affecting sustainable mobility requirements, namely, the urban sprawl and increasing energy costs. Finally the conclusion recommends the use of research and expertise networks in order to help the design and the implementation of suited solutions.  相似文献   

14.
Some South African cities have initiated public transport transformation projects which, in most cases, ultimately envisage the in toto replacement of paratransit operations with formalised BRT systems. There are two likely outcomes: (1) complex negotiations with existing operators and budget constraints will result in the in toto transformation occurring over an extended period of time; or (2) in toto transformation will simply not occur. In either case, cities will depend, for decades, on a ‘hybrid’ public transport system that combines both formal and paratransit operators. This paper presents a case for policy recognition of hybrid systems, and explores how such systems might best be managed. The following categories of hybrid public transport systems are explored through case studies: (1) transformative processes in which paratransit operators are to form or assimilate into companies to operate new services, but this incorporation has proved difficult to complete and the operational and regulatory frameworks remain unchanged; and (2) transformative processes that, from the outset, anticipated a hybrid system and designed the outcome accordingly. A third category of hybrid transport systems, defined as transformative processes that have been amended following a realisation that in toto transformation is unattainable, is also introduced and discussed. The paper concludes by tentatively drawing lessons for appropriate public transport regulation, particularly with respect to Cape Town's transformation project. It is argued that a review of the current national regulatory framework is required to enable possible project modifications that acknowledge system hybridity. It is suggested that regulatory frameworks that accommodate the likely hybrid nature of public transport system outcomes have greater prospects of success than frameworks that do not. Furthermore, it is argued that contextually appropriate and successful public transport transformation projects do not necessarily require the in toto substitution of incumbent paratransit operators, and that they can be integrated with, and complement, formal services.  相似文献   

15.
深海油田的开发--当前国际应用及发展趋势   总被引:2,自引:0,他引:2  
张大刚 《中国造船》2005,46(4):41-46
本文概述了现有的采油平台设计先进技术对深海油田开发和对未来发展趋势的影响.现在正在进行和最近刚刚安装的深海项目有十几个,其中一些项目正在创立新的记录,成为这个行业新的"第一",这包括用辅助船体协助"干井"式平台的钻井,新的安装方法,加速的施工方法,和上张力采油管道直接由采油平台支撑.本文将对其中一些项目作较为详尽介绍.此外,作者还阐述了个人对深海发展面临的技术挑战的看法.这些挑战包括水深的限制,安装方法,采油管道的支撑,以及采油操作方面的问题.同时亦将概述一些能使深海采油延伸到这些新领域的先进技术.  相似文献   

16.
Over the preceding decade, the World Bank committed about US$7.5bn in loans for urban transport projects in its client countries, involving total project costs of nearly US$13bn. Projects are designed by the client city/national governments and the World Bank in an interactive, give-and-take process. As is common in development finance, urban transport projects entail an investment program and a set of policy and institutional initiatives. A majority of Bank-funded operations in this period focused on public transport modes. A clear and overarching strategic thrust is evident, favoring private delivery of services with a strong public role through city-specific regulatory agencies. Depending on the context, projects involved efforts to introduce private operators and competition into an all-public set-up, or tighten up weakly regulated, “informal” public transport markets. A notable feature of many projects in the latter context is the use of investments in bus rapid transit infrastructure to reach multiple goals: improve transport services, maintain affordability for low-income passengers, attract new passengers, reduce negative environmental impacts, and leverage complementary reforms of policies and institutions. The Bank’s program in China, unique in its local context of a dynamic urban society moving away from a near-universal reliance on bicycles, initially did not focus on public transport but on urban roads and traffic management. Towards the end of the last decade, the motorization process and the outlook of decision makers entering a more mature stage, projects in China started to converge towards what the rest of the Bank’s program was doing – searching for a more sustainable path to urban transport development.  相似文献   

17.
Dynamics of Russian dry ports   总被引:2,自引:0,他引:2  
The transportation of cargos in containers has been intensively developing over the last decades. The world pace of growth in container transport is about 11% annually while in the Russian Federation from 2003 to 2007 the average growth was 21%. Container transportation is going to increase due to the construction of huge infrastructure projects for the Winter Olympics games in Sochi 2014, which implies the transportation of the required material flow. Foreign car assembly on Russian territory is developing, supplied by component parts delivered from Japan and the Republic of Korea, as well as from China that now bring 21.3% import container transport to Russia. About 60% of Russian container traffic passes through seaports Saint Petersburg, Novorossiysk and Vladivostok. The scenarios for increasing capacity to meet demands ahead are enhancing the productivity of seaports sites or leading to the creation of terminals in the hinterland. Although the phenomenon of dry ports is spread all over the world, in Russia none of the seaports has sufficient number of these facilities. The inland terminals of Russian seaports will be analysed from a dry port perspective. Despite the impediments, there are ecological and economical benefits that are discussed in the article. The advantages to the transport chain suggest that dry ports are a promising area for Russian seaports’ welfare.  相似文献   

18.
The objective of the paper is to analyze evolution of urbanization, transport demand and supply in Greater Cairo (GC) over the last three decades of the 20th century. This is in addition to investigating the impact of city growth on energy consumption and emissions from transport. It utilizes results of 1971, 1978, 1987, 1998 and 2001 travel demand surveys, undertaken during the corresponding GC transport studies; each was published a year or two later. No further transport studies have been carried out in GC over the past decade and in view of the current political situation, it is not envisaged that similar studies will be undertaken in the near future. The analysis includes the evolution of daily trips, trip purpose share, modal share and number of cars. More recent trends for 2006/2007 vehicle registration by type and size are given. The evolution of transport supply covers projects until early 2012. In parallel estimates of the evolution of energy consumption and cost, emissions of greenhouse gases (CO2) and pollutants (CO, HC and NOx) are given for 1971/2001. The adopted estimation methodology is summarized. Comparative analysis of relevant evolution indexes and trends of growth between 1971 and 2001, taking the former as base year, is given. Land use and transport policies and projects that in some cases helped, directly or indirectly, to reduce traffic congestion, or at least prevented an increase, are addressed, commenting on their outcomes. Thus, transferable experience are useful to sister cities benefiting from successes and avoiding drawbacks. The evolution of the impact of GC metro on energy consumption and cost, and GHG emissions is given for 1987/2001, assuming the scenario “metro did not exist”. More recent impact analysis is given for 2007/2008, as the data allowed estimating traffic volumes that would have been added to the congested metro corridors under the above scenario; and the related fuel consumption and cost and GHGs. The paper ends with conclusions on GC evolution, learned lessons and suggests repeating similar work in other mega cities of the developing countries. Further research is emphasized, e.g., modeling the relationship between land use, transport, energy and emissions; modeling emission factors by vehicle type; and studying fuel-subsidy-reduction scenarios and their socio-economic effects.  相似文献   

19.
One of the most striking problems societies currently deal with is to assure adequate quality standards while improving accessibility within and between cities. In addition there is also a growing awareness that, to achieve a sustainable balance between private and public means of mobility, policies have to be able to send the correct signals in order to induce users adaptive behaviour, which in turn will provide the system with a reliable feedback on the needs for further investment and expansion of transport facilities. The definition and measurement of quality of service of the transport system is thus an objective aimed by both users and producers and it is often represented by the rather holistic concept of Level of Service (LoS). However, the LoS concept is not consciously used by users, on the contrary the user concentrates her comparative evaluation on what is simply known as quality. It is the planner that translates planned quality into LoS concept. So, LoS is a concept at the interface between the provider and the user. Given the interface character of the LoS concept an accounting framework for LoS should thus take into account the need to segregate the evaluation for passengers and freight transport and also distinguish between types of travellers in the case of passenger transport and types of commodities or logistic families in the case of freight transport. Moreover the bridge between the planner and the user view must be ensured. This paper reports the results of a research work dedicated to this topic.  相似文献   

20.
Given the private sector character of the UK port system it might well be thought that, so far as port development is concerned, the market ruled. There are of course permissions to be obtained, including planning consent under the Town and Country Planning Acts; but this process has not so far been considered to interfere with market function. Ports are already well used to the process of obtaining approval, to negotiations with objectors and environmental interests, and to mitigating the effects of development when defining projects and seeking approval.

However, as ports policy is being brought into line with transport policy generally, and in particular with Government policy for sustainable development, ports are being faced with a more challenging regulatory framework. The search for sustainable transport is leading Government towards a broader based approach to the approval of development applications in which market need and commercial viability are simply two of a number of considerations which ports must take into account in designing projects which also meet environmental concerns.

There has been a long standing requirement for developers of major projects to carry out Environmental Impact Assessments. In addition Government policy is set out in a number of publications, applying sustainability and the associated “New Approach to Transport Assessment” (NATA) to the ports sector. In a separate and broader initiative it has also considered a radical reform of the planning system and the establishment of national priorities for infrastructure combined with a simplification of the Public Inquiry process. In the event it has been decided not to establish national priorities in the ports sector, although the aim of simplification of the Inquiry process remains.

The aim of this paper is to explore the emerging theoretical and practical issues arising within the development approval process. These are of most concern in the development of major projects for cargoes which have broad hinterlands, and where there are competing locations for new facilities. The most important example of this is in the deep sea container sector where there is a demand for new capacity and a choice of widely spaced locations in the south east of the UK. Some comment will be made on this sector and on the issues arising at the Public Inquiries for the proposed container port developments at Dibden Bay (Southampton) and the London Gateway at Shellhaven on the north bank of the Thames.  相似文献   

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