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1.
The role of spatial spillover associated with the infrastructure–economy relationship has received increasing attention in the literature. Surprisingly, in previous studies, the potential spatial spillover effect of transportation infrastructure on economic output in the U.S. agricultural sector has not been taken into account given the sector’s importance in the economy and dependence on transportation. The broader effects, including the direct effect and spatial spillover effect, of transportation infrastructure on agricultural output across 44 states in the United States from 1981 to 2004 are estimated in this study. A spatial Durbin panel data model that catches spatial dependence in both dependent and explanatory variables is used. The results suggest that road disbursement in a given state has positive direct effects on its own agricultural output. Also, the spillover effect of road infrastructure on agricultural output in neighboring states varies with respect to the spatial weight matrix used in the model. Moreover, our analysis shows that enhancement in road infrastructure in the states in the U.S. central region has a larger positive spillover effect on agricultural output when compared to coastal or border states.  相似文献   

2.
The importance of “broader” economic effects of transportation infrastructure has recently become apparent. “Broader” refers to impacts beyond the geographic boundaries within which the infrastructure investments are undertaken. Approaches to estimate “broader” impacts in production and cost function models are evaluated. A contribution of this paper is the empirical demonstration with a cross-section of US states’ manufacturing data that ignoring broader effects of a spatially lagged dependent variable can lead to mis-statements of the overall productive impacts of public infrastructure. These inaccuracies can arise because of missing indirect effects and from specification bias that may directly impact the infrastructure elasticity.  相似文献   

3.
This study explores how and to what extent transport infrastructure investment affects the level of agglomeration and consequently impacts on firm productivity, using transport network data and micro-data for manufacturing firms in the Seoul region. A first-difference model with novel instrument variables is developed to obtain more precise results than those in previous studies, and the partial arbitrariness that exists in previous studies is reduced by using the estimated spatial-decay parameter. An accessibility indicator derived from a multi-modal travel model is also applied to increase the accuracy in the measurement of agglomeration. It is found that an increase in the degree to which transport infrastructure investment improves the level of agglomeration raises firm productivity, with a best estimated elasticity of 0.0452. The finding highlights the key role of transport infrastructure investment in strengthening the level of agglomeration and the resulting economic advantages for production and economic actors. It is suggested that a policy for transport projects be implemented to maximise their cost effectiveness and ensure that agglomeration is promoted in the area where they are developed.  相似文献   

4.
The achievement of good spatial accessibility and equity in the distribution of urban services is one of the supreme goals for urban planners. With Scottish Government backing, the City of Edinburgh Council (CEC) has started to construct a tram network to cater for the future needs of Scotland’s capital city by providing an integrated transport solution using trams and buses. Spatial Network Analysis of Public Transport Accessibility (SNAPTA) which is a GIS-based accessibility model has been developed to measure the accessibility by public transport to different urban services and activities. The model responds to several limitations in other existing accessibility models in planning practice. It offers an alternative and practical tool to help planners and decision makers in examining the strengths and weaknesses of land use – transport integration. SNAPTA has been applied to a pilot study in Edinburgh city to identify the contribution of the infrastructure improvements of the tram system and Edinburgh South Suburban Railway (ESSR) to improved accessibility by public transport to six types of activity opportunities. This paper outlines the concept and methodology of the SNAPTA model, and presents the findings related to this pilot study with a focus on changes in potential accessibility to jobs between four different public transport network scenarios. The accessibility values so obtained help to identify the gaps in the coverage of the public transport network and the efficiency in the spatial distribution of urban services and activities. The findings focus on whether the planned transport infrastructures for Edinburgh will lead to better accessibility and reduced inequity (in terms of accessibility) across the city.  相似文献   

5.
The purpose of this paper is to examine the effect of various aviation infrastructure dimensions over aviation fuel consumption reduction (AFCR) performance. This study is an effort that considers the role of dimensions collectively from all aspects belonging to aviation infrastructure. The relevance of dimensions and constructs for hypothesis development are based on extensive literature review. Exploratory factor analysis (EFA) and Confirmatory Factor Analysis (CFA) were performed in the consecutive purification processes. Also, hypothesis testing was conducted using Structural Equation Modeling (SEM). A customized questionnaire was developed for collecting data from both kinds of respondents: Aviation industry experts and academic experts. Out of 382 approaches through mail survey, a total of 194 valid responses were collected. Analysis of the results shows the positive and significant impact of various factors such as: airport design, airspace management and air traffic control over the aviation fuel consumption reduction. Maximum importance is adjudged on air traffic control (ATC) and airspace route flexibility. The results of this study will encourage airlines and airport development authorities to increase their insight over aviation infrastructure, also to perform deeper analysis and find out precise values for real life implications.  相似文献   

6.
Housing affordability is traditionally measured using the percentage of household income spent on housing. An important cost that is usually overlooked in measuring location affordability is the transportation or accessibility costs. In this paper, we present a modeling approach, driven by urban open data, to measure location affordability that incorporates both housing and transportation costs. We apply the developed model to assess housing affordability in Melbourne, Australia as a case study. Results suggest that neighbourhoods that appear to be affordable when only housing cost is considered are not necessarily affordable when transportation costs are taken into account. A negative correlation between housing affordability and transportation affordability is observed. We also identify the presence of a strong spatial clustering pattern in the affordability measure across the study area. A major methodological contribution of the paper is the inclusion of comprehensive private vehicle costs and public transportation expenses in the model that contributes to a more robust estimation and understanding of location affordability. The model also distinguishes between different trip purposes. Results suggest that plans and policies to improve housing affordability should be made in coordination with transportation infrastructure investment plans to ensure effective and equitable outcomes. Nevertheless, the focus of the paper is more on the measurement of affordability; rather than reviewing and recommending housing related policies.  相似文献   

7.
The notion of co-locating alliance carriers to their designated terminals in airports has gained significant interest in recent years. While benefits on the part of airlines are made clear by existing literature on alliance-hubbing, the tangible benefits to airport operators are less clear due to a lack of studies in the literature. This paper considers existing cases of London Heathrow, Paris Charles de Gaulle and Tokyo Narita Airport, and applies their operational practices to a medium-sized airport in Asia Pacific to evaluate the universal applicability of alliance member co-location. Although some operational and financial improvements are observed, the paper concludes that implementation of this concept should not be done through a one-size-fits-all approach.  相似文献   

8.
Using a robust transfer function model methodology, the present paper seeks to offer empirical evidence regarding the size and type of effects that low-cost carriers (LCCs) have had on traffic for charter carriers (CCs) in the Spanish airport system by geographic market. We show an unmistakable substitution relationship between CCs and LCCs in the latter's typical niche markets, national and European flights, while there is no reaction from the CCs in the segment of international flights outside the EU. Furthermore, substitution effects are smaller between CCs and LCCs on the domestic level than effects between LCCs and network carriers (NCs) and slightly larger on the European level. Lastly, CC traffic's different sensitivity to terrorist attacks, day of the week, air accidents and the economic crisis is also evident. CCs should therefore be considered an independent category that warrants individualized analyses.  相似文献   

9.
This paper investigates how the entry of low-cost carriers in Southern Italy has supported local and regional economic development in different ways: spreading the traffic demand during the year, increasing the rate of international tourism, generating new jobs and improving the income of the area. The evidence of traffic de-seasonality is quantified by an index, resulting in a decrease to all those airports specialized in low-cost services. Additionally, an assessment shows that the net impact driven by a low-cost route on the local economy is about €14.6 million per year.  相似文献   

10.
Replacing conventional vehicle taxis with electric vehicles would be an efficient measure to reduce greenhouse gas emissions. Due to the limited range and long charging times of current battery electric vehicles, it is of utmost importance to provide sufficient charging facilities. This article analyses the impact of the placement and charging power of charging stations on potential mileage and revenue of electric taxis on the example of Singapore. Therefore, we developed an agent-based electric taxi simulation model to investigate electric taxis’ driving profiles with respect to different vehicle types and charging infrastructure designs. This model is also capable of simulating conventional taxi driving profiles. The validation of these simulation results with real taxi data showed that the model is reproducing taxi driving profiles with high accuracy in great detail. We found out that electric taxis could reach the same mileage and revenue as conventional taxis if charging with a power of 160?kW is possible. Furthermore, we discovered that waiting times for available charging stations have a stronger effect on revenue than the length of detours to reach charging stations. Based on these findings, we concluded that it is more important to reduce waiting times by placing sufficient numbers of charging stations at each location before expanding the charging network by installing small numbers of charging stations at many locations.  相似文献   

11.
This study explores the level of segregation experienced by seniors, children/youth, and passengers with disabilities, compared to normal-fare passengers at their trip destination when using public transportation. One week's travel records of public transit passengers were extracted from Seoul's transport card data to compute dissimilarity and exposure indices, theoretically equivalent to those developed in segregation research, to capture destination-based segregation through mobility patterns. Additionally, a multigroup entropy index was computed to measure diversity by assessing the social mixture of all passenger flows in a spatial unit. The results revealed that segregation levels experienced by passengers based on their social groups are notably different depending on the time of day and the day of the week. The computed exposure measure illustrates that the potential interaction between the selected social groups and normal-fare passengers is relatively higher during peak hours on weekdays. The results also show that subway stations provide more opportunities for interaction among different social groups. These findings can contribute to a better understanding of social segregation through mobility patterns as well as the effective quantification of the public transport network performance in terms of providing an interaction opportunity for the groups.  相似文献   

12.
This paper examines how alliance co-specialization and scope extension affect firm value at the time of alliance formation and termination, and whether value creation upon alliance formation also explains value creation upon termination. Building on the relational view of the firm, we develop predictions that are tested using event study methodology and data on code-sharing alliances formed, extended, and terminated between 1994 and 2008. The findings suggest that from a stock market perspective alliance formation and termination can be seen as two interrelated events and that it is difficult to reverse initial valuations past the alliance formation phase. They also suggest that the stock market reacts to alliance formation more critically than to post-formation decisions such as alliance scope extensions and terminations.  相似文献   

13.
The demands on airport infrastructure around the world are both growing and changing. This paper explores what problems these changing demands imply for airports, and how they are coping with them. Growth in demand imposes a problem of allocation of scarce capacity in the short run—how well mechanisms such as the slot system are coping with them is explored. In the long term, increases in capacity are warranted, and how the emerging ownership and regulatory environments for airports will handle these is examined. Changes in patterns of demand will come from new business models, such as low-cost carriers and from new aircraft types, such as the Airbus A380—the implications of these for airports of these are considered. Finally, the issue of airport cost efficiency, and how ownership and regulatory environment impact on it, is examined.  相似文献   

14.
Survey data on reverse logistics processes from 284 Spanish firms are used to test a structural model that analyzes the importance of returned materials and the creation of logistics knowledge within processes of reverse logistics and their effects on organizational performance. The results show that the cost of reverse logistics and the value of returns were found to be positively related to reverse logistics activities. Further, their proper management and the creation of logistics knowledge that improves organizational performance.  相似文献   

15.
Survey data on reverse logistics processes from 284 Spanish firms are used to test a structural model that analyzes the importance of returned materials and the creation of logistics knowledge within processes of reverse logistics and their effects on organizational performance. The results show that the cost of reverse logistics and the value of returns were found to be positively related to reverse logistics activities. Further, their proper management and the creation of logistics knowledge that improves organizational performance.  相似文献   

16.
The rising demand for residential development in the urban fringe of Christchurch, New Zealand, has led to an increase in car use and lengthening journeys, both of which have serious environmental implications. In light of this, the relationship between urban form and transport was investigated in Christchurch through the analysis of journey to work data from 1991 and 2001. Low density suburban areas were found to generate and receive the highest percentages of car trips in both 1991 and 2001. It was also found that the majority of work-trips involved suburb-to-suburb commuting, rather than to the centre of the city. Average trip length did not increase substantially over this period, although increases were apparent in separate modes. Multivariate regression analysis established that the key variable determining modal split and trip length was the distance the residence was located from the central business district. Results were similar when compared to larger cities elsewhere.  相似文献   

17.
Recent advances in transportation geography demonstrate the ability to compute a metropolitan scale metric of social interaction opportunities based on the time-geographic concept of joint accessibility. The method we put forward in this article decomposes the social interaction potential (SIP) metric into interactions within and between social groups, such as people of different race, income level, and occupation. This provides a novel metric of exposure, one of the fundamental spatial dimensions of segregation. In particular, the SIP metric is disaggregated into measures of inter-group and intra-group exposure. While activity spaces have been used to measure exposure in the geographic literature, these approaches do not adequately represent the dynamic nature of the target populations. We make the next step by representing both the source and target population groups by space–time prisms, thus more accurately representing spatial and temporal dynamics and constraints. Additionally, decomposition of the SIP metric means that each of the group-wise components of the SIP metric can be represented at zones of residence, workplace, and specific origin–destination pairs. Consequently, the spatial variation in segregation can be explored and hotspots of segregation and integration potential can be identified. The proposed approach is demonstrated for synthetic cities with different population distributions and daily commute flow characteristics, as well as for a case study of the Detroit–Warren–Livonia MSA.  相似文献   

18.
未来,随着工业化、城市化进程的加快推进,我国客货运输需求在总量增长和结构上均呈现出新的阶段性特征。近年来,随着铁路市场化改革、运输技术进步和运输组织创新,铁路在适应运输需求发展上表现出越来越灵活的适应性和越来越强的竞争力。在新的发展形势下,有理由相信,铁路运输不但会强化其固有的技术经济优势,而且会表现出在客货运输需求发展变化上的适应性优势,从而在整个交通运输行业乃至国民经济的发展中发挥更加重要的作用。  相似文献   

19.
Finding time and cost efficiencies associated with preliminary and final design of transportation projects has become increasingly difficult. Major new complexities present interesting and challenging project management issues and many agencies have incrementally adapted the project development process to improve efficiencies. Yet our understanding of the project development process is limited and the incremental changes in the process have not resulted in major modifications in the way in which transportation project development is approached for most agencies. A time honored method for elucidating problems with project development and potential solutions to them has been through the use of governmental audits. For example, over the past 30 years some 14 performance audits and evaluations have conducted of the California transportation project development process. These California audits have suggested that voter or legislatively approved projects, in terms of time, cost, or scope, significantly enhance project efficiencies. In this study, we examine time and cost project development efficiencies between voter or legislatively approved projects and projects with standard scopes. We find no significant evidence that state highway projects with highly defined, voter or legislatively approved project scopes, time, or costs are any more likely to have lower project development costs or times than projects with non-voter approved scopes.  相似文献   

20.
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