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1.
Abstract

This paper examines 42 business‐as‐usual (BAU) scenarios for future transport and traffic development in the Netherlands from the period 1970 to 2000. An important aspect of these scenarios is that they indicate the potential future state of the transport system if the policies in place at the time continue unchanged, thus raising issues which may require a policy response. This paper shows that in most of the important BAU transport scenario results of the past in the Netherlands, such as future car use and transport emissions, the policy makers were not misled. The prognoses for traffic congestion are an important exception as they underestimated the congestion problems that would arise. This paper shows that, based on the research it examines, BAU transport forecasting is an inaccurate practice. It is recommended that the BAU scenario designer communicates this high inaccuracy, enabling the policy maker to include the inherent future uncertainty in their decision‐making.  相似文献   

2.
The newly-built tunnel passing closely under the existing station will inevitably lead to settlement of the existing station, and especially deformation joints are prone to differential settlement. Based on the Suzhoujie Station of Beijing Subway Line 16 passing closely under the existing Line 10, this paper analyzes the overall settlement of the existing station and the differential settlement at deformation joints through a combination of field measurement and numerical simulation. The study results show that installing jacks significantly prevents the settlement of the existing station, after installation of jacks the settlement of the existing station is reduced by about 58%, and the jacking force of the jack shall be controlled between 180-450 t; the impact of construction on the single-deck station structure side at deformation joints is greater than that on the double-deck station structure side, the stress on the socket is gradually increased with the excavation of the lower tunnel, and reduced after installation of jacks, indicating that the jack can effectively reduce the tensile stress of the existing station and maintain the safety of the existing station; with the action of the jacking force of jacks, the settlement curve of the existing station presents a stepwise change at the jack installation points, while the upper ground surface settlement is relatively uniform. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

3.
Abstract

The economics literature offers many examples of studies of the economic impact of transportation infrastructure such as highways, ports, and airports; however, little attention has been paid to other types of infrastructure such as logistics platforms. This article is a first assessment of the economic effects of the largest logistics platform in Europe – PLAZA, the Zaragoza Logistics Platform – located in Spain. More precisely, this paper analyzes the economic significance of PLAZA on the economy of the Aragon region where it is located. The methodology is based on the application of input–output analysis to the final demand of logistics platform-based companies in a manner that is similar to well-established studies of the economic impacts of tourism on tourist expenditure. This makes it possible to quantify the various levels of economic effects (direct, indirect, and induced) in terms of jobs, salaries, and wages, turnover, gross operating surplus (GOS), and gross value added (GVA). The conclusions reveal the economic importance PLAZA has for the regional economy of Aragon, representing just over 2% of total GVA and 3% of turnover.  相似文献   

4.
In order to further evaluate the intelligent degree of the coal mining face scientifically and reasonably, this paper constructs a gray relational analysis based comprehensive evaluation model for the intelligent degree of mining face by deeply analyzing the influencing factors on the intelligent degree of mining face, such as surrounding rock detection, mining equipment, production system, supporting production system, organization and management, etc. By quantifying and scoring factors affecting the intelligence degree of mining face, using the hierarchical analysis method to obtain the weights and determine the correlations, the intelligence degrees of mining face are classified into four levels: excellent, good, medium and poor. Using the comprehensive evaluation model to empirically verify the 802 working face of Shaanxi Huangling Mining Co., Ltd., the calculated correlation is 0.765 8, which indicates that the intelligent degree of 802 working face is excellent according to the rating criteria, and it is consistent with the actual situation. Therefore, the comprehensive evaluation model based on gray relational analysis can accurately and objectively evaluate the intelligent degree of the mining face. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

5.
Although inevitably there are grey areas, a distinction may be drawn between environmental disbenefits arising from vehicles which cause annoyance, such as noise, or loss of peace and quiet, vibration, visual intrusion, severance, and those which endanger life and limb. Legislation implemented to reduce either category will inevitably generate costs.It is suggested that in evaluating legislation relating to environmental nuisance, attempts should be made carefully to measure the benefits, while for legislation when life and limb is involved a cost-effectiveness approach should be adopted. Methods currently available to measure environmental nuisance arising from vehicles, for example opinion surveys, observing the effect of changes in some independent indicator, and simulation exercises are critically examined. Using evidence from the Urban Motorway Committee Reports, Noise Advisory Council, Transport and Road Research Laboratory surveys on the effect of traffic in selected High Streets, and the Realistic Environment Assessment Laboratory, Social and Community Planning Research ping-pong technique, studies of house price differentials, and estimates of willingness-to-pay for exclusion facilities, an attempt is made to highlight the dilemma that while benefits of environmental nuisance legislation should be carefully weighed against the anti-pollution costs, techniques currently available for measuring such benefits are very underdeveloped.Paradoxically there is a far more clear-cut procedure for valuing benefits of policies affecting life and limb. Official accident evaluation policy in the U.K. is described, and legislation affecting life and limb is examined.Finally, difficulties of effectively enforcing legislation of both environmental nuisance and life and limb categories are illustrated.  相似文献   

6.
When car users’ are questioned about the advantages and disadvantages of car use the focus should not be on what they say, but on how they present their arguments to the interviewer. This paper shows such arguments can differ in kind. Swedish car users present the advantages––such as ‘time-saving’––by referring to personal and direct experience. The disadvantages are of two kinds. Some are related to direct experience, such as ‘costs’. Some are made credible by reference to public discourse, notably ‘environmental degradation’. This indicates that the facts about the advantages and environmental impacts are constructed in different ways. Facts about the advantages and some of the disadvantages are constructed in a direct and unreflexive way, situated in practical actions, and leave little room for negotiation. Facts about environmental impacts are constructed by others in a distanced and reflexive process, situated in laboratories, etc. Car users adopt these facts through various media. While the arguments on the advantages of car use are presented as unquestionable and absolute, scientific facts about the negative effects of car use are presented as relative and negotiable. This should be seen as a possible explanation why people do not reduce their own car use, although they say that car use in general ought to be limited.  相似文献   

7.
This paper examines the discretionary time-use of children, including the social context of children’s participations. Specifically, the paper examines participation and time investment in in-home leisure as well as five different types of out-of-home discretionary activities: (1) shopping, (2) social, (3) meals, (4) passive recreation (i.e., physically inactive recreation, such as going to the movies or a concert), and (5) active recreation (i.e., physically active recreation, such as playing tennis or running). The social context of children’s activity participation is also examined by focusing on the accompanying individuals in children’s activity engagement. The accompanying arrangement is classified into one of six categories: (1) alone, (2) with mother and no one else, (3) with father and no one else, (4) with both mother and father, and no one else, (5) with other individuals, but no parents, and (6) with other individuals and one or both parents. The utility-theoretic Multiple Discrete-Continuous Extreme Value (MDCEV) is employed to model time-use in one or more activity purpose–company type combinations. The data used in the analysis is drawn from the 2002 Child Development Supplement (CDS) to the U.S. Panel Study Income Dynamics (PSID). The results from the model can be used to examine the time-use choices of children, as well as to assess the potential impacts of urban and societal policies on children’s activity participation and time-use decisions. Our findings also emphasize the need to collect, in future travel surveys, more extensive and higher quality data capturing the intra- and inter-household interactions between individuals (including children). To our knowledge, the research in this paper is the first transportation-related study to rigorously and comprehensively analyze the social dimension of children’s activity participation.
Chandra R. Bhat (Corresponding author)Email:

Ipek Nese Sener   is currently a Ph.D. candidate in transportation engineering at The University of Texas at Austin. She received her M.S. degrees in Civil Engineering and in Architecture, and her B.S. degree in Civil Engineering from the Middle East Technical University in Ankara, Turkey. Dr. Chandra R. Bhat   has contributed toward the development of advanced econometric techniques for travel behavior analysis, in recognition of which he received the 2004 Walter L. Huber Award and the 2005 James Laurie Prize from the American Society of Civil Engineers (ASCE).  相似文献   

8.
The ancient Romans built an excellent system of roads, the development of which required systematic planning, creative design and high-quality construction and maintenance capabilities. At the empire’s peak about 85,000 km (53,000 miles) of road connected the capital Rome with its far-away frontiers. Twenty-nine major public roads radiated from Rome, the most famous of which was Via Appia (The Appian Way), also called the “queen of roads”. Built in 312 BC, it is the most illustrious example of Roman civil engineering skills; small sections of it are still in use today. What were the major reasons underlying this (and similar) massive and costly undertakings? How was it constructed so as to last for so many centuries? How much real resources were invested in its construction and what were the principal benefits? These are the main questions that this study aims to examine.  相似文献   

9.
Combining with the borehole gas concentration tests for the Sichuan red-bed section of the Chengdu-Guiyang Railway, this paper analyzes its correlation with the stratum chronology geological structure, and tunnel depth on the basis of data statistics, and puts forward the suggestion to qualitatively and quantitatively divide gas working areas. The results show that the correlation between the tunnel gas concentration and the stratum chronology is not significant in the Sichuan red-bed section of the Chengdu-Guiyang Railway (except coal-bearing strata); geological structure plays a controlling role in gas transport and accumulation; and the positive correlation between the gas concentration and the tunnel depth is significant. According to the above conclusions, it could qualitatively divide the gas working areas according to the geological structure and mapping information collected during the survey stage, and quantitatively divide the gas working areas according to the gas concentration test results. The final categorization of gas working areas can be determined by combining the qualitative and quantitative results. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

10.
Abstract

An introduction to random-utility-based multiregional input–output models used for the purpose of spatial economic and transport interaction modelling is provided. The main methodological developments and important results of a dozen applications from the years 1996–2013 are described. This is followed by an outlook of potential future directions. Further research is mainly needed in five areas: (a) overall validation of the method, perhaps through back-casting applications on infrastructure plans with observed trade impacts; (b) extensions of trade coefficient models to add realism and improve accuracy; (c) the use of multi-scale modelling to capture interdependencies between geographical scales and to improve the representation of exports and imports; (d) improvements in the representation of price effects, as well as innovation and technological progress, by way of variable technical coefficients; and (e) a deeper investigation of the algorithm used to include elastic selling prices.  相似文献   

11.
ABSTRACT

The economic development and spatial impacts of high-speed rail (HSR) are quite varied and mixed. Studies of economic impacts of HSR fall into two categories: predictions and empirical observations. We first review studies that examine predicted HSR impacts related to job growth, real estate development, and other economic effects. These are followed by studies examining observed effects of realized projects using the same categories. Several patterns emerge. Predictive studies are largely optimistic of the rail's positive effects. On the other hand, observational studies tend to identify both benefits and shortfalls. Yet, neither of these patterns are universal and depend on a number of other factors. One consistent pattern is that gains associated with HSR appear to be stronger in first-tier cities. Nevertheless, certain small towns and second-tier cities have undergone noteworthy transformations as a result of HSR, especially where the public sector has actively pursued new investment.  相似文献   

12.
13.
This paper questions some aspects of the technical soundness and public acceptability of environmental traffic management scheme of the kind advocated in the Buchanan report, Traffic in Towns. Practical studies have shown that in inner city areas in particular, and perhaps older built-up areas in general, the concept cannot be adequately defended against a wealth of variety of criticism from those whom it most directly affects, i.e. the public. Participation exercises have revealed public fears that the road closures associated with schemes will ruin the viability of local shops, worsen the environmental conditions along local roads chosen as distributors, cause even greater congestion on the main road network due to displaced traffic, and impede the accessibility of local people to their homes. In the light of these, it is suggested a flexible policy be adopted incorporating changes to the forms of vehicles and the manner in which they are used as well as changes to the physical form of the road network.The opinions expressed in this paper do not necessarily reflect those of the organisations to which the authors are attached.  相似文献   

14.
Abstract

This paper investigates route choice behaviour on freeways between Taipei and Taichung in Taiwan under the provision of real-time traffic information. Two types of route choice selection rules (the best-route and habitual-route) are analysed using ordered probit models to identify the major influences on freeway travellers’ route choice behaviour. The level of service associated with each route is defined as a generalised cost saving (GCS) and specified non-linearly with a threshold inherent to travellers. The marginal (dis)utility thresholds in the ‘best’ and ‘habitual’ behaviour models are identified through a goodness-of-fit grid. The results confirm that the thresholds for changing the inertia behaviour of drivers should be larger than the ones for choosing the best routes. In addition, the drivers are more likely to choose either the best or the habitual routes once the GCS are greater than the identified threshold values.  相似文献   

15.
Since immigrants will account for most urban growth in the United States for the foreseeable future, better understanding their travel patterns is a critical task for transportation and land use planners. Immigrants initially travel in personal vehicles far less than the US-born, even when controlling for demographics, but their reliance on autos increases the longer they live in the US. Cultural or habitual differences, followed by assimilation to auto use, could partly explain this pattern; and it may also be partly due to changes in locations and characteristics of home and work neighborhoods. Previous studies have rarely investigated non-work travel, and have not tested workplace land use measures, compared the relative influences of enclave and home neighborhood measures, or looked at the role of culturally-bound residential preferences or motivations for migration. This study relies on a unique and rich dataset consisting of a survey of US residents born in South Asia, Latin America, and the US, joined to spatial information in a GIS. I find that the home built environment is the most consistently influential factor in explaining the lower auto use of both recent and settled Latin American immigrants. Indian immigrants use autos less than would be expected given their home and work neighborhoods. There is little evidence that either ethnic enclaves, or cultural differences, play a role in lower auto use by immigrants. These results suggest there may be a role for neighborhood built environment policies in delaying immigrant assimilation to auto use in the US.  相似文献   

16.
In this paper, we take an initial look at the spatial and temporal flexibility in the activity patterns of the so-called “baby-boomer” cohort (born 1947–1966) in comparison with younger and older adults. Using a unique longitudinal survey carried in Quebec City from 2002 to 2005, we explore activity patterns and trip rates over a seven-day observation period during the first wave, and take a first look at some aspects of their evolution over two subsequent waves at about one-year intervals. We model the propensity to undertake activities within selected conventional non-work classifications such as “shopping” and “leisure”, and also according to respondents’ own perceptions of the spatial and temporal flexibility of each out-of-home activity that they had executed. While we cannot strictly separate cohort effects from age-related effects, after controlling for gender and household structure, we infer that age and related lifestyle effects dominate in explaining these propensities. However, the boomers were the only age stratum to increase their total out-of-home activity participation over the course of the panel, an intriguing starting point for the future study of this cohort.
Martin Lee-GosselinEmail:

Luis F. Miranda-Moreno   has been recently appointed as Assistant Professor in the Department of Civil Engineering and Applied Mechanics at McGill University. His research focuses on travel behaviour, transportation safety and evaluation of sustainable transport strategies. Martin Lee-Gosselin   recently retired as Full Professor at the Graduate School of Planning and CRAD, Université Laval, Québec, and is Visiting Professor at Imperial College London. His research interests are transport and telecommunications behaviour, survey methods, energy efficiency and the impacts of transport on the environment and public health.  相似文献   

17.
In the generally more dynamic modern business environment new modes of strategic planning have emerged, in which a premium is attached to the maintenance of flexibility in resource deployment. This paper discusses the principles involved, and considers the capacity of a segment of the sea ferry industry to exploit strategic flexibility as a means of coping with a rapidly changing environment. Potential sources of flexibility are examined in the paper and possible constraints identified. For the sector in question, it appears that strategic flexibility has been unduly limited by the nature of the resources employed, by prevailing corporate values, and by a tendency to respond to environmental uncertainty by short‐term reactions rather than long‐term measures. The general conclusion of the paper is that the sector examined, and possibly the industry as a whole, is strategically weak.  相似文献   

18.
Urban green spaces provide various social and environmental benefits that strongly improve the quality of life in a city. Municipalities are responsible for maintaining their green spaces in order to preserve these potentials. This paper supports municipalities in planning the transportation and disposal logistics of the green waste that is produced by the maintenance activities. The approach combines ecological issues like the seasonality of green waste generation and different types of biomass with economically driven decision making. We show how to determine cost efficient transportation plans for the disposal logistics and how to capture the seasonality of green waste generation when booking capacities at disposal facilities. It is also shown how a municipality can select the disposal facilities to cooperate with in a competitive environment where facilities offer capacities at differing conditions, as is the case for disposal sites that dump the green waste and for conversion plants that use the biomass for producing renewable energy. We illustrate the approach using case data of a major city in Germany.  相似文献   

19.
The effects of fuel price on travel demand for different income groups reveal the choices and constraints they are faced with. The first purpose of this study is to understand these underlying choices and constraints by examining the variation of fuel price elasticity of vehicle miles travelled (VMT) across income groups. On the other hand, the rebound effect—increase in VMT as a result of improvement in fuel efficiency may offset the negative effect of fuel price on VMT. The second purpose of this study is to compare the relative magnitudes of the fuel price elasticity of VMT and the rebound effect. A system of structural equations with VMT and fuel efficiency (MPG, miles per gallon) as endogenous variables is estimated for households at different income levels from 2009 National Household Travel Survey. Higher income households show greater fuel price elasticity than lower income households. Fuel price elasticities are found to be ?0.41 and ?0.35 for the two highest income groups, while an elasticity of ?0.24 for the lowest income group is identified. The rebound effect is found to be only significant for the lowest income households as 0.7. These findings suggest the potential ability of using fuel price as a tool to affect VMT. The study results also suggest possible negative consequences faced by lower income households given an increase in fuel price and call for more studies in this area.  相似文献   

20.
Rockburst is one of the main disasters for tunnelling under high ground stress. Taking the rockburst section of Ping'an Tunnel with high ground stress, which is located on Chengdu-Lanzhou Railway, as the study object, this paper adopts combined methods of filed measurement, numerical analysis, and laboratory test, and with respect to rockburst development mechanism, energy density change and rockburst strength it comprehensively analyzes the impact of two construction schemes (single-tube double-track tunnel system and double-tube single-track tunnel system) on the rockburst in deep-buried extra-long tunnels with high ground stress. The study results show that the order relation of maximum energy density at various locations of the tunnel is Uside wall >Uhance >Utunnel face >Uvault, and rockburst easily occurs at the working face of the tunnel section to be excavated and both side walls of excavated and supported section; compared with vault, hance, side wall and other locations, more energy would be released at the tunnel face, and the stress release holes shall be reasonably installed in the process of excavation; the doubletube single-track tunnel system scheme can effectively reduce the rockburst intensity and the rockburst hazards, so as to better avoid the occurrence of rockburst. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

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