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1.
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   

2.
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   

3.
Abstract

Numerous studies have found that suburban residents drive more and walk less than residents in traditional neighbourhoods. What is less well understood is the extent to which the observed patterns of travel behaviour can be attributed to the residential built environment (BE) itself, as opposed to attitude‐induced residential self‐selection. To date, most studies addressing this self‐selection issue fall into nine methodological categories: direct questioning, statistical control, instrumental variables, sample selection, propensity score, joint discrete choice models, structural equations models, mutually dependent discrete choice models and longitudinal designs. This paper reviews 38 empirical studies using these approaches. Virtually all of the studies reviewed found a statistically significant influence of the BE remaining after self‐selection was accounted for. However, the practical importance of that influence was seldom assessed. Although time and resource limitations are recognized, we recommend usage of longitudinal structural equations modelling with control groups, a design which is strong with respect to all causality requisites.  相似文献   

4.
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   

5.
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   

6.
Paratransit refers to urban transport services “somewhere between private passenger transport and conventional public transport in terms of cost and quality of service” [Rimmer (1980), Paratransit: A commentary. Environ. Plan. A 12, 937–944]. Since the 1980s, a new form of paratransit—residents’ coach, which provides exclusive transport services to residents living in private housing estates—has emerged in Hong Kong. What was the background underlying the emergence and subsequent growth of residents’ coach services? Also, what was the role of residents’ coach in the public transport system of Hong Kong? With the completion of more railway extensions, should residents’ coach services be replaced? If so, what are the potential impacts on people’s life? This paper addresses the above research questions through a large-scale questionnaire survey that examined not only people’s modal choice but also their residential choice, socio-economic background and attitudes. The findings suggest that transport policy makers should pay more attention to examine new forms of paratransit and the ways of integrating them into the overall public transport system, both spatially and temporally. It is only through the development of an efficient and multi-modal transport system can the maximum potential of paratransit in filling the transport gap between conventional mass transit and private cars be realized.  相似文献   

7.
This paper describes an integrated methodology for identifying potential ‘quick wins’ for mode shift from road to passenger rail transport. Firstly, a procedure for analysing rail’s relative competitiveness in the market for passenger transport between large urban areas is developed and then applied to a UK case study. The purpose of such analysis is to allow the identification of flows where rail is currently relatively uncompetitive (in terms of journey time in particular) and to assess the reasons for this poor performance, so that the issues which suppress rail use may be addressed. In parallel, a framework, methodology and tool for the assessment of existing and potential capacity (trains, seats, TEUs, etc.) is developed for both passenger and freight traffic, to identify and address network constraints. An illustrative example of the use of these demand and capacity assessment tools is then presented, with the tools used to identify and evaluate flows where rail demand is suppressed by poor service quality and where spare capacity exists which would allow the passenger rail service to be improved without requiring significant investments in infrastructure. The effects of such improvements on demand are predicted, and the cost implications of operating such additional services are discussed. The analysis suggests that there may be significant potential for increasing rail’s mode share by providing additional inter-urban services where rail currently offers an inferior service.  相似文献   

8.
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   

9.
In order to attract more choice riders, transit service must not only have a high level of service in terms of frequency and travel time but also must be reliable. Although transit agencies continuously work to improve on-time performance, such efforts often come at a substantial cost. One inexpensive way to combat the perception of unreliability from the user perspective is real-time transit information. The OneBusAway transit traveler information system provides real-time next bus countdown information for riders of King County Metro via website, telephone, text-messaging, and smart phone applications. Although previous studies have looked at traveler response to real-time information, few have addressed real-time information via devices other than public display signs. For this study, researchers observed riders arriving at Seattle-area bus stops to measure their wait time while asking a series of questions, including how long they perceived that they had waited.The study found that for riders without real-time information, perceived wait time is greater than measured wait time. However, riders using real-time information do not perceive their wait time to be longer than their measured wait time. This is substantiated by the typical wait times that riders report. Real-time information users say that their average wait time is 7.5 min versus 9.9 min for those using traditional arrival information, a difference of about 30%. A model to predict the perceived wait time of bus riders was developed, with significant variables that include the measured wait time, an indicator variable for real-time information, an indicator variable for PM peak period, the bus frequency in buses per hour, and a self-reported typical aggravation level. The addition of real-time information decreases the perceived wait time by 0.7 min (about 13%).A critical finding of the study is that mobile real-time information reduces not only the perceived wait time, but also the actual wait time experienced by customers. Real-time information users in the study wait almost 2 min less than those arriving using traditional schedule information. Mobile real-time information has the ability to improve the experience of transit riders by making the information available to them before they reach the stop.  相似文献   

10.
We hypothesise that intra-household interaction influences home departure time and mode choice for the morning commute. In Indonesia, over 71% of vehicles on the road are motorcycles. This fact increases the significance of household interaction in influencing transport mode choice since the simplicity of the motorcycle allows a great degree of versatility in regard to multiple family member transport. To emphasise this point, our study focuses on the unique travel behaviour of adolescents during the school morning commute which, due to the use of the motorcycle, is a combination of the travel behaviour of accompanied children and escorting adults. Our study discovers that adolescents are likely to shift their school arrival time very early or close to the designated starting time in relation to motorcycle-based parental escort to school. In regard to mode choice, adolescent students prefer to be escorted by motorcycle rather than take public transport.  相似文献   

11.
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   

12.
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   

13.
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   

14.
Abstract

In this paper, a methodology for capturing the transit passenger’s point of view by using both rating and choice options is proposed. For this purpose, some discrete choice logit models are introduced; the models allow the probability of choice of some alternative transit services to be calculated, and the importance of each service aspect to be determined. The models are calibrated by using data collected by a survey in which a stated preferences experiment was proposed to a sample of passengers, and some judgements were expressed by them about their transit services, in terms of perceptions and expectations. The introduced methodology provides a relevant contribution from a practical viewpoint because it allows the identification of the most important aspects on overall service quality; it is useful to the transit operators for measuring service quality and for investing on the various service aspects in order to effectively improve transit services.  相似文献   

15.
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   

16.
Research has shown that parental attitudes are a significant predictor of children’s active commuting (walking or biking) to school. However, the impact of parental gender on parental attitudes, and the link between parental attitudes and the gender gap in parental chauffeuring behavior have not received much attention. This paper examines these questions by applying discrete choice models to California data from the 2009 National Household Travel Survey while controlling for a wide range of variables characterizing parents, their children, households, schools, and the local built environment. Our results, conveyed via odds ratios, show that mothers are more likely to have higher concerns about traffic volume, which in turn reduces the likelihood that their children will walk or bike to school. Moreover, even though parental attitudes significantly influence parental chauffeuring behavior, their ability to explain the gender chauffeuring gap is limited. When holding equal concerns, mothers are still more likely than fathers to chauffeur their children to school. Finally, while distance to school and several land use measures (e.g., population density, urbanization level, and percentage of renters) are statistically significant, the impact of an objective measure of walkability is quite small. These results suggest that interventions targeting an increase in children’s walking and biking to school should focus on the concerns of mothers, especially as they relate to traffic characteristics.  相似文献   

17.
In order to explore the control method of the intake air state in utility tunnels when the outside fresh air humidity is too high, taking the ventilation works of a utility tunnel section in Pingtan comprehensive experimental area as the research background, this paper proposes the control method of intake air state parameters for ventilation and dehumidification in utility tunnels under normal and accident conditions, by means of the effective ventilation and dehumidification duration prediction model, the evolutionary multi-objective algorithm (EMOA), and in combination with the ventilation control requirements. The results show that the intake air state parameter controller can be adjusted freely according to the different requirements of decision makers for ventilation fan working duration and dehumidifier working temperature and moisture content, and the optimized appropriate control objectives can be achieved, which is conducive to the real-time decision-making of the intake air state parameter control for ventilation and dehumidification in utility tunnels. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

18.
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   

19.
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   

20.
Moshe Givoni 《运输评论》2013,33(6):685-688
Abstract

This paper reports on what appears to be the first attempt to map the perceived holistic dynamics at work in contemporary Brazilian railway development. The published perspectives of recognized experts in the Brazilian railway industry were mapped using the problem structuring methodology known as Strategic Options Development and Analysis (SODA). SODA is essentially a cognitive mapping approach and, in this case, it enabled a classification of the issues involved in railway development, as well as the detailed analysis of particular causes and effects acting upon the issues. Two particularly disturbing results are discussed in some length: the detrimental effects of the alleged misappropriations of public funds, and the identification of a degenerative feedback loop system at the heart of railway decision‐making. Overall, the paper shows that the situation faced by railway development in Brazil is constituted by a dynamic interaction of non‐independent problems, indicating the presence of a complex problem‐system requiring conceptual structure in a manner that permits analysis without ignoring systemic integrity. As such, the paper serves as a platform from which further use of SODA in this context might be considered as a decision support tool.  相似文献   

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