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1.
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   

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.
EFECT is a generalised methodological framework for evaluating the impacts resulting from transportation projects with a specific orientation to environmental impacts. The innovative aspect of the methodological framework is the combination of Multi-Criteria Analysis (MCA) with Cost-Benefit Analysis (CBA) methods to come up with an overall assessment of transport initiatives’ impacts over different geographical regions and time periods. Thus, it addresses both spatial and time impacts of transportation networks for all modes. The framework comprises four steps: structuring, weighting, rating, and exploring. Uncertainty is explicitly treated in the framework through fuzzy sets or, indirectly, through sensitivity testing. EFECT, using an additive function combining MCA and CBA methods, provides simplicity and intuitive understanding of results. This allows the use of either a core approach with a basic set of criteria and weights, or the application of a more detailed evaluation, when needed. The way EFECT is applied and the results produced are presented through a case-study example.  相似文献   

4.
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   

5.
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   

6.
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   

7.
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   

8.
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   

9.
This paper discusses the key findings from a research project that assessed the impacts of the Port Authority of New York and New Jersey??s Time of Day Pricing Initiative on the behavior of passenger car users. The survey data, comprised of 505 observations, show that 7.4% of passenger trips changed behavior because of the time of day pricing initiative, and that demand is inelastic to tolls with elasticities in the range of ?0.11 to ?0.24. Passenger car users who changed behavior responded to time of day pricing by implementing multidimensional strategies (3.23 different behavioral changes per user on average), involving behavioral responses such as changes in facility usage, changes in time of travel, changes in the payment type, and changes in mode/occupancy. The most frequently cited behavioral response was to shift mode, either to transit or carpool, and maintain the original time of travel (done in 2.55% of trips), instead of changing time of travel and maintaining the use of the passenger car (0.69% of trips). This reluctance to change travel schedules is undoubtedly a reflection of the limited time of travel flexibility that, on average, was estimated to be 20.4 and 12.3 min for early and late arrival for work-related trips. This, in turn, suggests the need for comprehensive policies, possibly involving incentives or regulations to foster employers?? participation in staggered/flexible work hour programs. Such approaches, combined with time of day pricing, are likely to be more effective in balancing car traffic during the day. Other behavioral responses of significance were reduce the number of trips made during the weekday peak-hours (1.65%), and switching to EZ-Pass to take advantage of the toll discounts (0.81%).  相似文献   

10.
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   

11.
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   

12.
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   

13.
A review of the air pollution studies carried out to study the dispersion of vehicular exhaust emissions (VEEs) has been made. The review includes the modelling studies in the domain, primarily, of analytical modelling – deterministic mathematical models and numerical models, and statistical models. Various model performance evaluation and comparative assessment studies have also been discussed. Further, the studies conducted to model VEEs at the urban road intersection and urban street canyons have also been reviewed.  相似文献   

14.
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   

15.
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   

16.
Increasing awareness and concern about the status of mobility-disadvantaged groups in society has given rise to a wide body of research that focuses on the social exclusion dimension of transportation. To date, much of the empirical work on this topic is mainly spatial in nature despite recent developments that call for the inclusion of time use analyses in social exclusion research. In this paper we attempt to fill this gap by estimating activity and trip durations to determine whether poverty, old age, or being a single parent results in time use patterns indicative of exclusion. Given the importance of shopping and using services for social inclusion objectives, these activities are the focus of this investigation. In terms of methods, use of a multiple equation approach allows for the estimation of the daily duration of shopping activities and trips while simultaneously controlling for daily durations of four broad categories of activities as well as their associated travel times. The results indicate: that being a senior citizen increases travel durations while decreasing shopping activity durations; that coming from a low income household decreases shopping activity durations; and single-parent status does not impact shopping activity durations when holding income and other activity durations constant. These results highlight the feasibility and challenges of time-use and activity analysis in social exclusion research.  相似文献   

17.
This paper presents the evaluation results of three traffic solutions for the complex grade-separated intersection located in the old part of Belgrade at the junction with the new bridge over the Sava River. The corridor to which the intersection belongs together with the new river bridge are parts of a great urban artery called the Inner Half Semi-Ring Road (IHSRR). The traffic solutions that are evaluated are defined in the preliminary design phase, based on two opposed concepts: a complete grade separation of all intersection legs (the CPV alternative – ‘grade-separated’) and a grade separation designed to minimise construction costs (DMC 1 and 2 alternatives – ‘minimise cost’). The evaluation procedure is conducted in three steps: first, the score based on expert assessment of the functionality of the design solutions is determined; second, the alternatives are ranked according to the value of a set of state indicators obtained by micro-simulation using PTV–VISSIM 4.10; and third, the final score is obtained by multi-criteria evaluation using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. The results of the first evaluation step show a small advantage for DMC 2, a sub-alternative of the DMC 1 alternative. The results of the micro-simulation give advantage to the DMC 1 alternative. The multi-criteria evaluation provides a better ‘goodness factor’ for the CPV alternative against the DMC 1 alternative. At the same time, the least construction cost favours alternative DMC 1.  相似文献   

18.
Abstract

This paper summarizes the state-of-the-art for assessing the value of a statistical life (VSL) as a component of the costs of road accidents. It focuses on the most popular approaches for assessing the VSL, with respect to its theoretical foundations, current state-of-research and empirical evidence. Our paper also provides a first (to our knowledge) compendium of results for the VSL based on Stated Choice (SC) methods. Among the analysed alternatives, the willingness-to-pay (WTP) appears to be the leading approach for assessing the VSL and the SC methods represent the current state-of-the-art for determining the WTP for non-market goods. We conclude that the SC approach overcomes some of the most important shortcomings of the alternative approaches and offers a significant flexibility that can be used to address its own limitations. We also identify a significant need for research, as a gap between the methods employed in research (SC methods) and the state-of-the-practice (other methods) has emerged.  相似文献   

19.
Abstract

Women form an important part of the workforce originating from the slums in the city of Delhi, India. The paper illustrates that women spend more time travelling on slower modes of transport to access work; the faster modes are more expensive. Their time–poverty demands they look for work at shorter distances from home. The basic argument presented is that their ability to contribute to the alleviation of their standard of living and their status in society is severely curtailed by their limited mobility and the constrained accessibility to the transport system of the city. This transport deprivation becomes further exacerbated by the process of forced eviction and relocation of low‐income households to the periphery of the city, causing the women to lose livelihood opportunities.  相似文献   

20.
Current signal systems for managing road traffic in many urban areas around the world lack a coordinated approach to detecting the spatial and temporal evolution of congestion across control regions within city networks. This severely inhibits these systems’ ability to detect reliably, on a strategic level, the onset of congestion and implement effective preventative action. As traffic is a time-dependent and non-linear system, Chaos Theory is a prime candidate for application to Urban Traffic Control (UTC) to improve congestion and pollution management. Previous applications have been restricted to relatively uncomplicated motorway and inter-urban networks, arguably where the associated problems of congestion and vehicle emissions are less severe, due to a general unavailability of high-resolution temporal and spatial data that preserve the variability in short-term traffic patterns required for Chaos Theory to work to its full potential. This paper argues that this restriction can now be overcome due to the emergence of new sources of high-resolution data and large data storage capabilities. Consequently, this opens up the real possibility for a new generation of UTC systems that are better able to detect the dynamic states of traffic and therefore more effectively prevent the onset of traffic congestion in urban areas worldwide.  相似文献   

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