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81.
通过浮选机叶轮盖板部试用合成橡胶2 年多的实践,认为橡胶件具有重量轻、寿命长、经济效益显著等特点。证明采用备件质量与价格挂钩的方式,有利于提高备件质量。 相似文献
82.
综合分析丰城矿务局煤层瓦斯赋存情况和可供开采的瓦斯储量、瓦斯抽放及利用现状,借鉴国内外瓦斯发电的经验,提出了有效的综合利用设想———建立瓦斯发电厂。 相似文献
83.
本文通过介绍合肥荣事达集团CAD推广应用实施的全过程,分析CAD推广应用对企业发展的重要性和迫切性,以及CAD推广应用以后,给企业带来的生机和活力。 相似文献
84.
对工业企业的经济效益的综合评价展开了全面、细致的评述。从经济效益的界定、经济效益的分类和经济效益的评价等方面都一一作了扩展论述。并举出范例,对某企业年度的12项经济指标值,分别进行计算、加权、比较、分析,来判断说明该工业企业的综合经济效益水平。 相似文献
85.
电网企业配售电业务随着改革发展形势的变化,面临更强的市场竞争,用户对更加多元化、便捷化的能源电力服务的需求也愈加迫切,增值服务对于电网企业具有重要意义。以电网企业发展节能改造服务为例,通过构建相应指标体系及量化评估模型,实现对电网企业节能改造服务效益的综合评价,为电网企业评估节能改造服务的效益潜力提供决策支撑。 相似文献
86.
纤维素纤维赛络纺经济效益分析 总被引:1,自引:1,他引:0
为提高纤维素纤维纺纱的质量和经济效益,通过分析赛络纺工艺改进成纱强力和毛羽的特点,以竹浆纤维为例,计算了传统纺与赛络纺运行成本及赛络纺投资回收期.指出:纤维素类纤维采用赛络纺工艺的运行成本大于传统纺,但由于赛络纱质量较好、售价较高,因而可在较短的时间内实现投资回收. 相似文献
87.
甘蔗生产燃料乙醇--解决我国能源紧缺矛盾的最佳途径 总被引:9,自引:1,他引:8
本文指出,用甘蔗生产燃料乙醇,不会占用人的食粮和禽畜饲料,不会减少制糖原料和糖产量;乙醇的原料成本和加工成本都较用其他作物低;甘蔗单产和乙醇产量都较用其作物高;有成熟的甘蔗乙醇生产工艺和现成的生产设备;蔗农可获较种其他作物更高的收入,乙醇生产厂可获用其他作物作原料更高的效益。 相似文献
88.
V. Buytaert B. Muys N. Devriendt L. Pelkmans J.G. Kretzschmar R. Samson 《Renewable & Sustainable Energy Reviews》2011,15(8):3918-3933
Biomass is expected to play an increasingly significant role in the ‘greening’ of energy supply. Nevertheless, concerns are rising about the sustainability of large-scale energy crop production. Impacts must be assessed carefully before deciding whether and how this industry should be developed, and what technologies, policies and investment strategies should be pursued. There is need for a comprehensive and reliable sustainability assessment tool to evaluate the environmental, social and economic performance of biomass energy production. This paper paves the way for such a tool by analysing and comparing the performance and applicability of a selection of existing tools that are potentially useful for sustainability assessment of bioenergy systems. The selected tools are: Criteria And Indicators (C&I), Life Cycle Assessment (LCA), Environmental Impact Assessment (EIA), Cost Benefit Analysis (CBA), Exergy Analysis (EA) and System Perturbation Analysis (SPA). To evaluate the tools, a framework was constructed that consists of four evaluation levels: sustainability issues, tool attributes, model structure, area of application. The tools were then evaluated using literature data and with the help of a Delphi panel of experts. Finally, a statistical analysis was performed on the resulting data matrix to detect significant differences between tools. It becomes clear that none of the selected tools is able to perform a comprehensive sustainability assessment of bioenergy systems. Every tool has its particular advantages and disadvantages, which means that trade-offs are inevitable and a balance must be found between scientific accuracy and pragmatic decision making. A good definition of the assessment objective is therefore crucial. It seems an interesting option to create a toolbox that combines procedural parts of C&I and EIA, supplemented with calculation algorithms of LCA and CBA for respectively environmental and economic sustainability indicators. Nevertheless, this would require a more comprehensive interdisciplinary approach to align the different tool characteristics and focuses. 相似文献
89.
Architecture, engineering, and construction industry participants often find it pragmatic to implement a project-specific dispute resolution ladder (DRL) as a managerial tool to assist in the prompt resolution of claims and change orders (CCOs) that might arise during the project construction phase. This project-specific DRL consists of a single or multiple alternative dispute resolution (ADR) techniques that require capital expenditures to cover the expenses incurred by the owner’s/contractor’s employees and third-party neutrals. If a project-specific DRL is properly chosen, then the capital expenditures are outweighed by the expected benefits from the DRL implementation; namely, prompt resolution of the CCOs without incurring excessive cost overruns on an already financially stressed project budget, as well as avoiding the escalation of the claims to a dispute that requires long protracted litigation for final settlement. Typically, the decision as to which ADR techniques to include in the project-specific DRL is undertaken during the project planning phase prior to the actual occurrence of the CCOs. In this case, the project owner decide to invest in a DRL in exchange for the expected savings in the project. This decision regarding the project-specific DRL is usually done based on the experience of the project parties with the ADR techniques. However, such a decision needs to be guided by a financial tool that allows the project owner to evaluate alternative DRLs and choose the most economically feasible alternative based on the project and ADR characteristics. In this paper, a financial model is developed to evaluate DRL implementations in construction projects by drawing analogies from real option theory with exogenous competitive entry. More specifically, the occurrence of a given CCO will result in a reduction in the value of expected savings in the project due to DRL implementation. This is similar to the reduction in the gross value of a capital investment project in a commercial property due to competitive entry by another similar commercial property developer in the market. At the same time, the CCO resolution due to an effective DRL implementation will allow project owner to recover part of the losses in the expected savings in the project due to the DRL implementation. The model presented in this paper takes into account the characteristics of the various ADR techniques included in the project-specific DRL, and the characteristics of the CCOs occurring during the construction phase of the project. A case study of a real construction project is used to illustrate the practical implementation of the model. The results indicate that for this case project and from a financial point of view, the investment in the chosen project-specific DRL was not worthwhile because of the high uncertainty in the project, and the low effectiveness of the selected DRL. These conditions did not provide the owner with the anticipated advantage of the DRL implementation in reducing the value of the CCOs occurring in the project. At the same time the cost of the DRL implementation exceeded the actual savings attained in the project. 相似文献
90.
Project-specific dispute resolution ladders (DRLs) are typically implemented in construction projects to resolve issues arising between the project participants. The DRL typically consists of single or multiple alternative dispute resolution (ADR) techniques to address construction issues at the three levels of escalation: conflicts; disputes; and claims. However, a DRL requires significant investments to cover the direct costs incurred in-house by the project participants or, externally, if construction specialists and lawyers are recruited to assist in the resolution. Thus, the benefits of the DRL implementation in a construction project must outweigh its costs for the implementation to be worthwhile. This paper presents a methodology to study the effect of different resolution strategies on the value of the investment in a DRL using option/real option theories from financial engineering, process centric modeling, and system dynamics methodology. Of particular interest in this paper is the integration of these research methodologies into a computer model to support the evaluation of the DRL investment in a particular construction project by taking into account the characteristics of (1) the project and (2) the different ADR techniques chosen for the DRL implementation. Finally, an example is presented to illustrate the application of the computer model in a real construction project. The results of the simulation serve two main purposes. First, the results of the simulation are used to verify the intended model behavior in terms of proper integration of the three methodologies (i.e., real options, process centric, and system dynamics) in one computer system. Second, the model application to a real construction project using actual project data illustrates the potential of the model in providing the project participants with information related to the expected number of claims and change orders resolved at each level of the DRL, the change in the expected savings during the construction phase, and finally the value of the investment from the perspective of the project owner. 相似文献