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71.
Climate change is increasing the speed at which tangible coastal cultural heritage is changing in character or being lost through weathering, erosion, and inundation. Damages to coastal archeological sites, loss of access to historical sites, and the alteration of cultural landscapes will force changes in the way researchers can study sites, tourists can enjoy places, and descendant communities who have lived in particular areas for time immemorial, and local community members can utilize and relate to landscapes. In the USA, the National Park Service is a primary coastal cultural resource management organization. The National Park Service has been working on climate change adaptation for cultural resources for over a decade; however, there are few examples of parks in which long range climate change adaptation plans for cultural resources have been implemented. Building from 20 semi-structured interviews with cultural resource managers in three parks, we found that institutional structures within the National Park Service, as well as historical conceptual framings specific to the research, recreational, and interpretive values of cultural resources act as barriers to managers’ ability to design and implement climate change adaptation plans. Institutional barriers managers discussed include the dependence of climate change adaptation decisions partnership projects and the leveraging of budgetary and staff resources within NPS that may affect climate change adaptation capacity. We found that park managers often saw impacts in parks that may be associated with climate change, but found it difficult to separate normal maintenance from climate change affected deterioration, which may lead to status quo management actions rather than revised planning for a changing future regime. Conceptual barriers managers discussed revealed a conflict between preservation needs of research versus interpretive uses and while NPS guidance recommends prioritization of cultural resources for preservation at the park level, regional managers were more focused on this topic than park managers. As NPS moves forward with climate change adaptation planning, opportunities to develop and improve cultural resource preservation with new technologies, improved prioritization schemes, and include public input in resource preservation may help coastal managers overcome these barriers.  相似文献   
72.
Costs of producing “advanced” biofuels (those with the lowest GHG and land use impacts) have not decreased in recent years as envisioned by analysts. Despite aggressive policy incentives, no transition to a lower cost mature industry has occurred. Information about the cost dynamics and slow industry emergence is of major interest to policymakers and others seeking to understand the likely success – and cost – of incentive programs. This paper reviews literature on production cost at the plantgate – without considering taxes or delivery costs – for selected biofuel technology pathways using a levelized cost of fuel approach, applying common financing assumptions for capital amortization and converting all values to year 2016 dollars, and examines results in the current low carbon fuel policy context. The average production cost estimate for cellulosic ethanol was $4 per gallon-gasoline equivalent (gge). For drop-in fuels, the pyrolysis-biocrude-hydro treatment pathway had the lowest average production cost estimate at about $3.25/gge. Biomass to liquid (BTL) production cost estimates averaged $3.80/gge, while hydrotreated esters and fatty acids (HEFA) – the sole fuel studied gaining commercial traction – averaged about $3.70/gge. Estimate ranges did not allow any definitive rank ordering of the fuels by production cost. Production cost estimates are higher in later than in earlier publications for non-HEFA fuels due primarily to higher costs for feedstock and capital expenditure components. This may reflect learning from early but largely unsuccessful commercialization efforts that yielded more realistic (and higher cost) information and detail on feedstock provision and conversion processes.  相似文献   
73.
This paper analyzes the interdependency across two critical infrastructures of transportation and motor fueling supply chains, and investigates how vulnerability to climatic extremes in a fueling infrastructure hampers the resilience of a transportation system. The proposed model features both a bi-stage mathematical program and an extension to an ‘α-reliable mean-excess’ regret model. The former aspect allows decision makers to optimize the pre-disaster asset prepositioning against the maximum post-disaster system resilience. The latter aspect of the proposed model devalues the impact of ‘low-probability, high-cost’ sub-scenarios upon model results. The model reveals the reliance of post-disaster urban mobility on the interdependent critical infrastructure of motor fueling supply chains. The results also suggest how investment in the fueling infrastructure’s vulnerable elements protects urban mobility while the transportation network is stressed or under attack.  相似文献   
74.
Massachusetts, like many coastal states in the US, stands to be impacted from climate-induced sea level rise. As a result, climate-sensitive coastal policy instruments are critical for providing adequate adaptation options, including an option to allow coastal features to migrate inland. But the migration of coastal features is under threat due to extensive private armoring. This essay highlights specific regulatory instruments at the federal and state level dealing with hard armoring using Massachusetts as an example. It argues specific federal and state regulations legitimize and incentivize hard armoring over other coastal land use planning methods. The current level of armoring in Massachusetts is highlighted and implications under current federal and state policy frameworks are explained. Suggestions for coastal states planning for sea level rise are discussed, including the need for state planning to take the lead. Recommendations for changes at the federal level are also highlighted.  相似文献   
75.
通过UTM剪切试验确定黏层油的种类及其最佳用量;分别成型沥青混凝土+防裂材料+水泥混凝土的剪切试件,通过UTM剪切试验测定不同浸水条件下各试件的抗剪强度;采用现场拉拔试验测定不同防裂材料结构层的抗拉能力。结果表明:采用SBS改性沥青作为黏层油,其最佳用量为1.0 kg/m2;不同潮湿气候条件中聚酯玻纤布层间抗剪强度大于其余两种防裂材料层间抗剪强度;相同潮湿气候条件中聚酯玻纤布层间拉拔强度大于防水卷材层间拉拔强度。  相似文献   
76.
为明确地铁站环控系统各项运行措施的节能潜力,制定有针对性的节能运行方案。通过对我国各气候区的屏蔽门地铁站环控系统全年能耗进行大规模模拟,系统而定量分析常见的运行管理参数优化后的节能潜力,包括取消小新风空调的机械新风、加强屏蔽门气密性、提高站内空调温度、提高冷机COP和提高空调箱能效比。研究结果表明:对于寒冷、夏热冬冷和夏热冬暖地区的屏蔽门地铁站,环控系统节能潜力最大的优化措施是提高站内空调控制温度,各站平均节能潜力在17%~21%之间;其次是取消机械新风供应、提高冷机COP和提高空调箱能效比,相应节能潜力在12%~20%之间,各措施的节能潜力大小和排序在不同气候区之间存在差异;节能潜力最小的措施是增强屏蔽门气密性,各站平均节能潜力在1%~4%之间。综合优化上述运行管理参数,寒冷地区、夏热冬冷地区和夏热冬暖地区的典型屏蔽门地铁站环控系统的年节能量分别为22万k Wh/a、37万k Wh/a和61万k Wh/a,节能百分比分别为41%、48%和52%。研究成果可为我国各气候区屏蔽门地铁车站节能运行提供基础数据支撑。  相似文献   
77.
根据昆明的气候情况,昆明地铁通风空调系统在地下站台公共区仅设置了通风设备。文章详细介绍了昆明地铁通风空调系统的制式、参数和构成等,并对其节能减排、节省投资和节约运行费用等优势进行论述。  相似文献   
78.
The transportation system is one of the main sectors with significant climate impact. In the U.S. it is the second main emitter of carbon dioxide. Its impact in terms of emission of carbon dioxide is well recognized. But a number of aerosol species have a non-negligible impact. The radiative forcing due to these species needs to be quantified. A radiative transfer code is used. Remote sensing data is retrieved to characterize different regions. The radiative forcing efficiency for black carbon are 396 ± 200 W/m2/AOD for the ground mode and 531 ± 190 W/m2/AOD for the air transportation, under clear sky conditions. The radiative forcing due to contrail is 0.14 ± 0.06 W/m2 per percent coverage. Based on the forcing from the different species emitted by each mode of transportation, policies may be envisioned. These policies may affect demand and emissions of different modes of transportation. Demand and fleet models are used to quantify these interdependencies. Depending on the fuel price of each mode, mode shifts and overall demand reduction occur, and more fuel efficient vehicles are introduced in the fleet at a faster rate. With the introduction of more fuel efficient vehicles, the effect of fuel price on demand is attenuated. An increase in fuel price of 50 cents per gallon, scaled based on the radiative forcing of each mode, results in up to 5% reduction in emissions and 6% reduction in radiative forcing. With technologies, significant reduction in climate impact may be achieved.  相似文献   
79.
80.
There is a considerable body of studies on the relationship between daily transport activities and CO2 emissions. However, how these emissions vary in different weather conditions within and between the seasons of the year is largely unknown. Because individual activity–travel patterns are not static but vary in different weather conditions, it is immensely important to understand how CO2 emissions vary due to the change of weather. Using Swedish National Travel Survey data, with emission factors calculated through the European emission factor model ARTEMIS, this study is a first attempt to derive the amount of CO2 emission changes subject to the change of weather conditions. A series of econometric models was used to model travel behaviour variables that are crucial for influencing individual CO2 emissions. The marginal effects of weather variables on travel behaviour variables were derived. The results show an increase of individual CO2 emissions in a warmer climate and in more extreme temperature conditions, whereas increasing precipitation amounts and snow depths show limited effects on individual CO2 emissions. It is worth noting that the change in CO2 emissions in the scenario of a warmer climate and a more extreme temperature tends to be greater than the sum of changes in CO2 emissions in each individual scenario. Given that a warmer climate and more extreme weather could co-occur more frequently in the future, this result suggests even greater individual CO2 emissions than expected in such a future climate.  相似文献   
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