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61.
会计是以货币为主要计量单位,对一定主体的经济活动进行全面、综合、连续、系统的核算与监督,并向有关方面提供会计信息的一种经济管理活动。而市场经济中的会计操守关系到会计和的生命线,是会计师的底线和灵魂。文章从会计诚信的必要性、会计诚信缺失的原因、会计诚信缺失的危害等方面加以分析,进而提出治理诚信缺失的对策。  相似文献   
62.
文章主要介绍了转向架构架焊接工艺补偿量计算系统的开发,通过将该系统对HXD1B型机车构架侧梁焊接收缩变形的计算,与实际焊接时产生的收缩变形尺寸进行对比,进而验证该系统的准确性。  相似文献   
63.
本文分析了公交企业树立市场营销观的必要性,对公交企业如何进行市场营销提出了一些建议。  相似文献   
64.
解读罗默的"一般剥削理论"   总被引:4,自引:0,他引:4  
罗默于1982年出版的《剥削和阶级的一般理论》是“分析的马克思主义”的经典之作,在这部著作中,罗默认为,马克思主义之所以陷入危机之中,是因为当代马克思主义者缺乏一个新的剥削理论,他从博奕论出发,提出了“一般剥削理论”,创建了“社会必要剥削”,“社会主义的剥削”等新概念,但这一理论也存在着难以消除的困难。  相似文献   
65.
Traffic signals, even though crucial for safe operations of busy intersections, are one of the leading causes of travel delays in urban settings, as well as the reason why billions of gallons of fuel are burned, and tons of toxic pollutants released to the atmosphere each year by idling engines. Recent advances in cellular networks and dedicated short-range communications make Vehicle-to-Infrastructure (V2I) communications a reality, as individual cars and traffic signals can now be equipped with communication and computing devices. In this paper, we first presented an integrated simulator with V2I, a car-following model and an emission model to simulate the behavior of vehicles at signalized intersections and calculate travel delays in queues, vehicle emissions, and fuel consumption. We then present a hierarchical green driving strategy based on feedback control to smooth stop-and-go traffic in signalized networks, where signals can disseminate traffic signal information and loop detector data to connected vehicles through V2I communications. In this strategy, the control variable is an individual advisory speed limit for each equipped vehicle, which is calculated from its location, signal settings, and traffic conditions. Finally, we quantify the mobility and environment improvements of the green driving strategy with respect to market penetration rates of equipped vehicles, traffic conditions, communication characteristics, location accuracy, and the car-following model itself, both in isolated and non-isolated intersections. In particular, we demonstrate savings of around 15% in travel delays and around 8% in fuel consumption and greenhouse gas emissions. Different from many existing ecodriving strategies in signalized road networks, where vehicles’ speed profiles are totally controlled, our strategy is hierarchical, since only the speed limit is provided, and vehicles still have to follow their leaders. Such a strategy is crucial for maintaining safety with mixed vehicles.  相似文献   
66.
社区教育资源是指可资学校教育活动的一切物质资源和精神资源的总和。它包括设施资源、人力资源、财力资源、文献资源、组织资源等。学校通过参与办理各种社区教育事业来开发与利用社区教育资源,可以扩充学校教育的功能,辅助学校的办学,促进学校教育的发展,同时可以推进建设学习型社区。  相似文献   
67.
The great majority of analyses made in transport economics use, explicitly or, more often, implicitly, the common assumption of perfect competition. This is the case, for instance, when infrastructure projects are evaluated using the mere sum of the surpluses of transport users and providers. Even when putting aside the question of externalities such as noise, safety or environmental quality, the real chain of economic interactions that takes place in transport provision or downstream of transport provision is not taken into account. Surely enough, describing and simulating this chain could be quite complex. Nevertheless, it is not uninteresting to try to estimate if it does make a big difference or not to make this approximation. The paper makes such an attempt for two broad kinds of applications of transport economics:  相似文献   
68.
Plug-in electric vehicles (PEVs) have the potential to reduce green house gas emissions from the transport sector. However, the limited electric range of PEVs could impede their market introduction. Still some potential users are willing to pay more for PEVs. The combined effect of these and other influencing factors as well as the resulting future market evolution are unclear. Here, we study the market evolution of PEVs in Germany until 2020. Our results reveal a great deal of uncertainty in the market evolution of PEVs due to external conditions and the users’ willingness to pay. We find the future share of PEVs in German passenger car stock to range from 0.4% to almost 3% by 2020. Energy prices have a large impact on PEV market evolution as a 25% increase in fuel prices would double the number of PEVs in stock by 2020 compared to a reference scenario. We find a special depreciation allowance for commercial vehicles and a subsidy of 1000 Euro as the most effective and efficient monetary policy options. The high uncertainty of the market evolution implies that policies to foster market diffusion of PEVs should be dynamically adaptable to react to changing framework conditions.  相似文献   
69.
The production and use of renewable fuels in the transport sector are rapidly increasing. Renewable fuel standard (RFS) is a strong regulatory component and quantitative policy expected to have a significant market impact. In Korea, RFS implementation was agreed upon in July 2013 and will be enforced beginning in July 2015. Drivers’ acceptance is the most important consideration for RFS introduction and sustainable implementation. This study analyzed Korean customer preferences for RFS and quantified their acceptance level according to policy design. A choice experiment was analyzed with a mixed logit model to reflect the heterogeneity of respondents’ preferences. Respondents were relatively sensitive to the price increase, while other attributes had little effect on acceptance of RFS. Differences between the influences of attributes on drivers’ acceptance should be considered when designing RFS implementation. Furthermore, it is recommended that the price of transportation fuels should be limited to an increase between KRW 10 and 20/liter (USD 8.879 × 10−3 and 1.776 × 10−2/liter) to ensure high acceptance level, secure a budget for infrastructure, and achieve substantial environmental improvement.  相似文献   
70.
诚信的信息披露是资本市场的基石,是确保建立公平、公开、公正资本市场的基本前提。我国证券市场由于发展迅速,在信息披露方面存在很多不完善的地方,从而造成财务舞弊事件时常发生,引起投资人及社会公众对上市公司的信任危机,严重影响了资本市场的发展。因此,建立完善的诚信信息披露机制是保证资本市场健康发展的有效途径。  相似文献   
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