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1.
This paper addresses the planning of recyclable waste collection systems while accounting for economic and environmental concerns. Service areas and vehicle routes are defined for logistics networks with multiple depots where different products are collected. The problem is modeled as a multi-product, multi-depot vehicle routing problem with two objective functions: distance and CO2 emissions minimization. A decomposition solution method is developed and applied to a real case study. Six scenarios regarding different service areas and objective functions are studied. Savings of up to 22% in distance and 27% in CO2 emissions are achieved, exceeding economic and environmental goals.  相似文献   

2.
International aviation is responsible for between 2.5% and 3% of anthropogenic carbon dioxide (CO2) emissions that are partly held responsible for climate change. International aviation is not subject to any regulatory framework for the limitation of these emissions. From an economic point of view, the introduction of an emissions trading scheme would be an appropriate instrument to limit these emissions. This paper outlines the possibilities on how aviation could be included in existing emissions trading schemes and gives an overview on the current political discussion. It continues with an empirical estimation of the impacts on operating costs and transport demand for low cost, full service, holiday and regional airlines taking Ryanair, Lufthansa, Condor and Air Dolomiti as examples, under three different design options for an emissions trading scheme. Finally, conclusions about the impacts on intra-European and worldwide airline competition are drawn.  相似文献   

3.
Accessibility, or the ease to participate in activities and obtain resources in a given environment, is crucial for evaluating transportation systems. Greater accessibility is often achieved by increasing individuals' potential mobility. However, potential mobility, if realized by motorized modes, can also generate negative environmental impacts such as fossil fuel consumption and greenhouse gas (GHG) emissions. While the negative environmental impacts of greater mobility are acknowledged, there has been a lack of research to validate those impacts using empirical data, especially considering variations in individuals' mobility levels. This paper presents a method for estimating the expected environmental costs of accessibility represented by a network-time prism (NTP). A NTP delimits all accessible locations within a network and the available time for an individual to present at each location given a scheduled trip origin and destination, a time budget and the maximum achievable speeds along network edges. Estimating the expected environmental costs of a NTP involves three steps: (1) semi-Markov techniques to simulate the probabilities to move along network edges at given times; (2) the speed profiles for reachable edges, and (3) a cost function that translates speeds into environmental impacts. We focus on air quality and employ the motor vehicle emission simulator MOVESLite to estimate the CO2 emissions at both the edge and prism levels. We calibrate and validate the methods for experimental NTPs defined within the Phoenix, AZ, USA road and highway network using vehicles instrumented with GPS-enabled onboard diagnostic devices (OBD). We demonstrate the effectiveness of our method through two scenarios and investigate the impact of changes in mobility levels on the expected CO2 emissions associated with the experimental NTPs.  相似文献   

4.
Tourism travel under climate change mitigation constraints   总被引:1,自引:0,他引:1  
The paper first describes an inventory for 2005 giving the tourism related CO2 emission caused by global tourism, and presents a 30-year projection and a 45-year simulation. The study found that tourists cause 4.4% of global CO2 emissions. Also these emissions are projected to grow at an average rate of 3.2% per year up to 2035. This increase is problematic as globally a reduction of emissions by 3–6% is required to avoid ‘dangerous’ climate change. Using contemporary scenario techniques it appeared difficult to find a future tourist travel system consistent with CO2 emission reductions of up to 70% by 2050 with respect to 2005. Based on the model underlying the 30-year projection, 70 scenarios are presented in a ‘landscape’ graph exploring the effect of opportunities to reduce the emissions, but this attempt did not reach the large reductions envisaged. We therefore explored automated scenario generation as a way to define backcasting scenarios that both reach the emission reduction target and retain the highest possible economic value for the sector. The main contributions made by this study are (1) in comparing the value of different ways to approach a (desired) future and (2) giving insight into the kind of structural changes required within tourism and tourism transport in case very strong emission reductions are required. Finally the model showed signs of ‘complex’ behaviour.  相似文献   

5.
The EU Council intends to regulate air transport's full climate impact (i. e., CO2 and NOx, H2O, SOx, aerosols, contrails and contrail cirrus). A likely approach is the inclusion of all climate relevant species from aviation in the European Emissions Trading Scheme. We provide a proposal for this practice and analyze the economic impacts. Modelling results indicate that the cost effects of the EU-ETS addressing CO2 and non-CO2 emissions will be much larger than under the current scheme. This is because under the new approach, all climate relevant species are regulated and not just CO2. The cost effects also depend on the length and altitude of the flight. Both have consequences for the competitive environment of the airlines under the scheme. Especially the full service network carriers will have to bear a competitive disadvantage compared to airlines offering just short- and medium-haul services. Remarkably, some cost effects are in opposition to the corresponding results for an ETS for the regulation of CO2 alone.  相似文献   

6.
Accessibility has been conceptualized and applied in different ways, depending on the underlying political objectives. In the context of climate change and ambitious emission reduction targets, environmental concerns have risen high on the political agenda. Existing methods for assessing transport-related environmental impacts typically depend on realized or modeled travel behavior. Many of them do not entail a spatial dimension, ignore the importance of the land use component, lack scenario building capabilities or have limited communication value. Consequently, accessibility analysis and planning could make a valuable contribution towards a low carbon transition, but needs to attune to the specific objective of reducing transport-related greenhouse gas emissions. This paper introduces a novel conceptualization of location-based accessibility, where CO2 emissions are used as a travel cost in place of time or monetary costs. By identifying and assessing options for interventions in the land use and transport system, carbon-based accessibility instruments might serve a number of potential decision-making purposes related to low carbon mobility planning. Carbon-based accessibility of a business park in the Munich region is analyzed in multiple scenarios to demonstrate the application potential of the method. The experiential application focuses on the effects of changes in vehicle efficiency and occupancy rates of both car and transit, but also compares the resulting carbon-based accessibility levels to alternative sites with the transport system unchanged. Applying carbon-based accessibility instruments to real-world planning issues could enhance strategic decision-making processes in the context of climate change mitigation.  相似文献   

7.
Transport is a major user of carbon-based fuels, and it is increasingly being highlighted as the sector which contributes least to CO2 emission reduction targets. This paper reports on the findings of the VIBAT London study (www.vibat.org) which considers the role of the transport sector in reducing CO2 emissions in London.The analysis develops a transport and carbon simulation model (TC-SIM) for London. Within this, users are able to consider the implementation of a series of potential policy packages—low emission vehicles, alternative fuels, pricing regimes, public transport, walking and cycling, strategic and local urban planning, information and communication technologies, smarter choices, ecological driving and slower speeds, long distance travel substitution, freight transport and international air. They can select variable levels of application to help achieve headline CO2 emission reduction targets. The roles of carbon rationing and oil prices are also considered. TC-SIM can be played in different user modes: as ‘free riders’, ‘techno-optimists’, ‘enviro-optimists’, ‘complacent car addicts’ and other typical travel market segments, including a ‘free role’. Game playing or scenario testing such as this helps to highlight perceived levels of homogeneity of views within certain cohorts, the development of entrenched positions and the likely success in achieving objectives.The paper develops various policy packages, scenarios and pathways aimed at reducing transport CO2 emissions. It argues that strategic CO2 emission reduction targets are very ambitious relative to current progress, and that we need to act more effectively across a wide range of policy mechanisms, with a ‘high intensity application’ of many of the options, to get near to achieving these targets. A critical issue here will be in communicating and gaining greater ‘ownership’ of future lifestyle choices with stakeholders and the public, and participation tools such as TC-SIM could become increasingly important in this area.  相似文献   

8.
Climate change is a global problem and across the world there are major difficulties being experienced in reducing carbon dioxide (CO2) emissions. The transport sector in particular is finding it difficult to reduce CO2 emissions. This paper reports on two studies carried out by the authors in London (UK) and Delhi (India). It considers the common objectives for transport CO2 reduction, but the very different contexts and baselines, potentials for change, and some possible synergies.Different packages of measures are selected and scenarios developed for each context which are consistent with contraction and convergence objectives. CO2 reduction potentials are modelled and quantified by package and scenario. London is considering deep reductions on current transport CO2 emission levels; Delhi is seeking to break the huge projected rise in transport CO2 emissions.The scale of policy intervention required to achieve these goals is huge and there is certainly little public discussion of the magnitude of the changes required. The paper argues for a ‘strategic conversation’ at the city level, using scenario analysis, to discuss the priorities for intervention in delivering low carbon transport futures. A greater focus is required in developing participatory approaches to decision making, alongside network investments, urban planning, low emission vehicles and wider initiatives. Aspirations towards equitable target emissions may assist in setting sufficiently demanding targets. Only then is a wider awareness and ownership of potential carbon efficient transport futures likely to take place.  相似文献   

9.
Time-definite freight delivery common carriers, who pickup, consolidate and deliver small shipments are a key third-party logistics service provider in the supply chains. Under uncertain demands, carrier’s multistage stochastic integer load planning in the pure hub-and-spoke line-haul operations network is to determine multistage freight paths and distribute trailers over time while meeting operational restrictions, service requirements, and balancing trailer inventory at the termination of planning horizon. We developed a heuristic approach, scenario aggregation with embedded branching on the binary variables. The numerical experiments showed a proactive operations strategy with a lower operating cost than the conventionally deterministic approach.  相似文献   

10.
This study tried to clarify the magnitude of CO2 emissions from highway construction and maintenance in China through life cycle assessment (LCA) method. For this, 227 real highway projects constructed from the year 2000 to 2011 in Zhejiang Province, China are classified into six types by two categories of N road (62 projects without grand bridge, great bridge and tunnel) and Y road (165 projects with the same road structures) and three sub-categories of (i) newly constructed road, (ii) replacing pavement road and (iii) full rehabilitated road. Significant influential factors of LCA results were revealed through multivariate linear regression models, combined with data quality assessment and sensitivity analysis. Numerical interval of assessment results indicate that the construction emissions of N highway project are more centralized to no more than 2900 t/lane-km, while Y project have a normal upper boundary of construction CO2 emissions, about 5000 t/lane-km. The contribution of maintenance to CO2 emissions probably could exceed that of newly construction both for Y project and N project. In addition, the pavement replacing and rehabilitation could bring about large amount of CO2 emissions which even match with the CO2 emissions from cumulative traffic volume during highway's life cycle. There are common factors for six categories. Cement and steel are the top largest CO2 emissions contributors and sensitive factors for N road and Y road. The LCA results are not sensitive to the local construction materials but sensitive to the emission factor of diesel used in transportation and on-site construction.  相似文献   

11.
面向电子供应链的企业物流信息系统的开发和建设,有助于实现企业、供应商、销售商之间的协调发展,减少库存,降低操作成本,缩短交易时间等。根据电子供应链的网络环境特点,在研究制造业企业物流一般流程的基础上,根据主、辅制造商物流流程,提出企业物流信息系统的参考模型结构设计。  相似文献   

12.
Chengdu, the capital city of Sichuan province, is the fourth biggest city in China with over 15 million residents and 3.4 million vehicles. In Chengdu, transport and other mobile sources accounted for over 27% of the city's PM2.5 emissions (CDEPB, 2016), posing negative impacts on public health, local environment, and the climate. This study estimated impacts from transport-related emissions (CO2, CH4, N2O, PM10, PM2.5, NOX, SOX, CO, and HC) and evaluated the associated social cost for Chengdu from 2005 to 2013. The study also assessed the city's transport performance in terms of its eco-efficiency with the socioeconomic and environmental concerns. The activity-based methodology was adopted to produce the emission inventories, while utilizing meta-analysis and localizing the emission social cost factors based on Chengdu's economic and demographic reality to support social cost assessment. The study marks the first attempt in literature to evaluate Chengdu's transport emission social cost. The following were observed in the study: (i) in 2013, the social cost of all transport emissions in Chengdu was around US$3 billion, with the lowest estimate of US$449 million and the highest estimate of US$4.7 billion; (ii) trucks, private cars, and motorcycles were the major contributors, while NOX, PM2.5, and CO were the key pollutants to public health; (iii) if GHGs (CO2, CH4, and N2O) were excluded, the upper range of social cost of transport air pollutants would be from US$2.4 billion to US$4.1 billion, or 1.6%–2.8% of the Chengdu's GDP.  相似文献   

13.
In logistics networks involving one supply point (depot) and several geographically dispersed demand points (e.g., retail stores), delivery shortages will result if the design of delivery routes ignores random period-to-period fluctuations in customer demands. Delivery shortages may be costly enough for the depot to seek strategies to prevent them. A requirement for rational comparison of strategies is quantifying their effects on total supply chain costs. Accurate distance prediction models are developed to help satisfy this prerequisite for the transportation cost element. These models are integrated into a comparison of strategies on the basis of how these strategies affect inventory and transportation. The focus of findings from the comparison involves identifying the information cost thresholds for accepting/rejecting a demand-responsive strategy. The study's implications for choosing a strategy are presented. ©  相似文献   

14.
We propose an efficient evolutionary multi-objective optimization approach to the capacitated facility location–allocation problem (CFLP) for solving large instances that considers flexibility at the allocation level, where financial costs and CO2 emissions are considered simultaneously. Our approach utilizes suitably adapted Lagrangian Relaxation models for dealing with costs and CO2 emissions at the allocation level, within a multi-objective evolutionary framework at the location level. Thus our method assesses the robustness of each location solution with respect to our two objectives for customer allocation. We extend our exploration of selected solutions by considering a range of trade-offs for customer allocation.  相似文献   

15.
In the last few decades, the building evidence that CO2e emissions lead to climate change has pointed to a need to reduce CO2e emissions. This research uses five scenarios in the context of UK import trade to assess total CO2e emissions and costs of import re-routing containers. The overall objective is to assess possible carbon mitigation strategies for UK supply chains by using a combination of alternative ports and revised multimodal strategies. The model adopted includes three elements: port expansion, container handling and freight transport. The alternative scenarios explore different settings modal shift and short sea shipping.  相似文献   

16.
This study examines carbon dioxide (CO2) emission changes from livelihood transitions during tourism development to assess the environmental impact of pro-poor tourism (PPT) in China. The results indicate that livelihood transitions during PPT increased household income but also produced more CO2 emissions. CO2 emissions vary depending on factors including livelihood types after transition, income and household sizes, etc. The CO2 per unit of income from tourism-based livelihoods is higher than from non-tourism-based livelihoods. Different livelihood strategies post transition also affect emissions. Practical suggestions that may mitigate emissions while not compromising residents’ income levels are provided.  相似文献   

17.
Freight transportation and logistics act as the artery of the national economy. With a booming economy, China's freight transport sector has experienced dramatic growth in recent decades and has become a key driving force of China's CO2 emissions. Therefore, effective and efficient mitigation policies in the freight transport sector are critical for China to promote CO2 emission mitigation strategies. In contrast to other countries, China's challenge stems not only from technical issues but also from regional socioeconomic disparities, which in turn require the implementation of locally oriented policies. For this reason, an analysis based on regional disparity is of vital importance for future policy making. However, to date, there have been few pertinent studies on the freight transportation sector. To fill this gap, this paper aims to conduct an in-depth comparative study of CO2 emission characteristics and the driving forces in the freight transport sector in China's three regions (covering 31 provinces) from 1990 to 2007. The log mean Divisia index method (LMDI) is employed to analyse the driving forces, and the Gini coefficient is used to investigate regional inequity. Additionally, regional disparity is explored in-depth based on the analytical results and practical concerns. The results highlight that economic structure is a key driving force for emissions change and reveal significant regional disparity and inequity in freight transport emissions. The results are critical for future policy-making to address regional concerns.  相似文献   

18.
Everyday traffic accounts for a significant share of overall greenhouse gas emissions, in particular carbon dioxide (CO2). While several solutions have been proposed for decreasing the emissions, a new kind of land use planning is required in order to achieve long-term effects. This study focuses on the effect of large retail store locations in the urban structure on overall CO2 emissions, by using the Oulu region, Finland, as a case study. The aim was to utilize GIS tools to assess store locations in terms of CO2 emissions from private cars used for consumer traffic. In this case, not only are the locations of the existing and planned retail units investigated with respect to population distribution and car ownership, but the analysis is also carried out by regarding any location within the study area as a hypothetical site for a large retail unit. According to the applied method, CO2 values are lowest near the centre of the studied region, the region with the highest population density, although the city centre itself did not turn out to be the most optimal location for a retail store in terms of CO2 emissions. Nevertheless, by generally reducing trip length, a compact urban structure is an important way of achieving long-term cuts in CO2 emissions.  相似文献   

19.
Decreasing carbon dioxide (CO2) emissions is one of the most important tasks for the society in the 21st century. One possibility to decrease emissions originating from transportation is to utilize more rails instead of relying simply on road transportation. In the dry port concept an inland intermodal terminal is connected to a sea port using railways. This study analyzes impacts of dry ports in a Finnish context. We compare two different configurations: In the first one shippers drive directly to a sea port, while in the second one they use dry ports. The systems are evaluated by using discrete-event simulation. In the systems we are interested in two issues: (1) Level of CO2 emissions, and (2) Costs to transport the goods in different configurations. We use different scenarios for future energy prices and estimate both the costs and CO2 emission development in these scenarios. We also compare the results to a situation, where emissions are minimized instead of costs. Implications on larger scale are also discussed, for example in the Baltic Sea and North Sea area, where strict sulfur emission restrictions are seen to harm sea transport and increase concentration on small number of sea ports.  相似文献   

20.
We examine a joint inventory replenishment and shipment scheduling problem that arises in the context of a vendor-managed inventory (VMI) arrangement. Since a temporal shipment consolidation policy is being implemented, the inventory requirements at the vendor are affected by the timing and quantity of shipment release. The vendor’s problem is to determine an integrated policy for inventory replenishment and shipment release and to set its parameters. We develop analytical models for computing such integrated policies where it is economical to use common carriage for outbound transportation. We propose algorithmic approaches to set the optimal policy parameter values.  相似文献   

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