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1.
The European Clean Vehicle Directive was introduced in 2009 to create an obligation on public authorities to take into account the impact of energy consumption, carbon dioxide (CO2) emissions and pollutant emissions into their purchasing decisions for road transport vehicles. This should stimulate the market for clean and energy-efficient vehicles and improve transport's impact on environment, climate change and energy use. Therefore the so-called ‘Operational Lifetime Cost’ of a vehicle is calculated, divided into the cost for energy consumption, CO2 and pollutant (nitrous oxide, particulate matter, non-methane hydrocarbons) emissions. In Belgium, a different methodology has been developed to calculate the environmental impact of a vehicle, called ‘Ecoscore’, based on a well-to-wheel approach. More pollutants are included compared to the Clean Vehicle methodology, but also indirect emissions are taken into account. In this paper, both methodologies are compared and used to analyze the environmental performance of passenger cars with different fuel types and from different vehicle segments. Similar rankings between both methodologies are obtained; however, the large impact of energy use (and CO2 emissions) in the Clean Vehicle methodology disadvantages compressed natural gas cars, as well as diesel cars equipped with particulate filters, compared to the Ecoscore methodology.  相似文献   
2.
This study examines airline passengers’ willingness to pay for carbon-offsets. Using the contingent valuation method of double-bounded dichotomous choice format and a survey of over 1000 Taiwanese passengers flying to countries in Asia, Europe, North America, and Oceania to gauge their willingness-to-pay for airline carbon-offsets. The results suggest that despite the trip characteristics and personal background, air travel passengers’ knowledge and perceptions of the carbon-offset scheme also greatly influence the stated willingness to pay.  相似文献   
3.
阐述了标度扩展AHP法的基本原理和步骤,基于该方法对三种典型战斗机的空战效能进行评估,结果表明,采用标度扩展的AHP法进行效能评估,可以减少计算量,并能提高结果的可信度。  相似文献   
4.
ABSTRACT

The literature on valuation of time charter contracts and real options in shipping generally relies on the complete markets hypothesis and the risk-neutrality of agents. However, these assumptions fail completely in some shipping market segments. This study proposes a numerical approach—based on discounting the certainty equivalent payoff at the risk-free rate—which incorporates the agent’s risk preferences through an exponential utility function. The method comprises an iterative Monte Carlo nested simulation with the real probability measure. This method is applied to a case of Suezmax tankers. The stochastic evolution of the time charter rates is modelled as a geometric mean-reverting process. The case study supports the applicability of the proposed method and evidences that the effect of risk preference may be significant, mainly for more risk-averse agents. Although the method involves intensive computation, it has the benefits of theoretical ease and flexibility, which could encourage utilisation by practitioners.  相似文献   
5.
工程量清单计价方法是国际上较为通用的一种先进的造价管理方法。文章指出我国水运工程造价领域应用工程量清单计价方法是必然趋势,并对计价模式进行了探讨,论述了其特点、意义及必须要做的工作。  相似文献   
6.
结合新颁布的《建设工程工程量清单计价规范》(2008年版),就投标报价策略技巧中采用的不平衡报价法进行探讨,并针对开发商的反不平衡报价措施提出了应对措施,对工程投标有一定借鉴意义。  相似文献   
7.
This article provides results on the net benefits generated from the natural resources in the Bohol Marine Triangle (BMT) in the Philippines. The BMT spans over 112,000 ha and its coastal ecosystems are rich in biodiversity and provide economic opportunities to the coastal communities. With a 10% discount rate, the accumulated total net benefits for the BMT resources over a 10-year period is US$11.54 million. Tourism and the municipal fisheries are the most important direct use values of the coastal and marine resources of the BMT accounting for 44% and 39% of the total net benefits. Annual revenues attributed to ecosystems were as follows: coral reefs, US$1.26 million; beach/intertidal area, US$1.12 million; marine waters, US$646,501; mangrove, US$239,561; and seagrass, US$105,990. The large market values indicate the dependence of the local community on the BMT coastal and marine resources. In the same way, non-market values show the important life-support functions of coastal and marine ecosystems. The net benefits reflect the magnitude of potential losses due to improper management of coastal and marine resources in the BMT. This valuation highlights the importance of the coastal services to the BMT economy and draws attention to the benefits the local stakeholders derive from BMT coastal resources. Policy measures can now take into account these values to justify a sufficient investment in coastal management efforts to sustain the flow of coastal services in the interest of current and future generations.  相似文献   
8.
建设工程实行工程量清单计价已开始推行。此文在介绍采用工程量清单计价的优点和意义的基础上,阐述工程量清单计价与定额计价存在的根本差异(定价方式和价格范围),并对存在的差异进行原因分析。通过分析与研究,提出缩小2种计价方式存在差异的应对措施:根据项目工期要求和对市场价格变化的预测,批复初步设计概算时应充分考虑预备费;缩短定额计价更新期,及时更新人工单价和主要材料价格;依据施工图编制工程量清单,研究开发工程量清单计价及管理系统软件,合理确定标的。  相似文献   
9.
高速公路作为投资大,建设周期长,回报率不高的公益性基础设施项目,决定了国家投入应是建设资金的主渠道,因此科学、合理、完善的政府投资高速公路计价依据十分重要。然而我国目前计价依据主要还是建立在计划时代条件下原有的定额体系的基础上,没有形成与工程量清单相适应的计价依据体系,而且工程定额的更新速度很慢,很难反应目前高速公路工程建设市场的实际情况。通过分析发达国家投资高速公路计价依据,从中参考一些值得借鉴的内容,进而对我国政府投资高速公路计价依据改革提出了几点建议。  相似文献   
10.
我国的工程造价长期以来按照传统的定额模式进行计价,目前推行工程量清单计价模式。工程量清单计价模式实行量价分离,由企业根据自身情况按市场规律自主报价,但是,工程量清单计价模式在并不成熟的市场经济条件下还不能彻底取代传统的定额计价模式,按定额编制概(预)算的造价管理方法仍然具有不可替代的作用,尽管如此,工程量清单计价的推行乃大势所趋。  相似文献   
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