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81.
我国可再生能源发展面临的问题及新机制的建立 总被引:7,自引:2,他引:5
中国可再生能源发展面临发电成本高、市场容量小、制造业薄弱、缺少立法支持和相应的运行机制等多种问题。解决这些问题的途径首先是推动可再生能源立法,其次,在立法的基础上进行可再生能源发展机制的创新,建立包括目标机制、定价机制、选择机制、补偿机制、交易机制和管理与服务机制等在内的运行机制。由于中国发展可再生能源要实现多种目标,因此不能依靠单一手段解决所有的问题。中国可再生能源发展的新机制应该是多种机制共同起作用的系统。 相似文献
82.
83.
WANG Jin-shu LIU Wei LIU Juan ZHOU Mei-ling 《材料研究与应用》2005,(3):616-620
Rare earth oxide doped molybdenum powders were prepared by the reduction of rare earth nitrites doped MoO3. The effect of rare earth oxide on the reduction behavior of molybdenum oxide had been studied by means of Temperature Programmed Reduction (TPR), thermal analysis, X-ray diffraction. Doping rare earth oxide in the powder could lower the reduction temperature of molybdenum oxide and decrease the particle size of molybdenum. The mechanism for the effects had been discussed in this paper. 相似文献
84.
介绍了一种用于稀土金属提纯的单晶炉,根据区熔法提纯单晶的特殊工艺要求,分析了其主要结构及特点。该设备也适用于多种激光晶体的生长和激光晶体的真空退火。 相似文献
85.
The syntheses,characterization and crystal structure of rare earth coordination compounds of five typicalextraction systems commonly used in the separation technology were reported.They are:(1)carboxylic acidsystem,(2)organophosphorous acid system,(3)quarternary ammonium salt system,(4)neutralorganophosphonate system and(5)synergistic system. 相似文献
86.
The kinetic behaviours of the substitution reaction of rare earth-PHA with CyDTA were studied systemati-cally.The relationship between the rate constant and atomic number was discussed.The rate differentiation val-ue R_d(R_d=lgk_(z n)-lgk_z)was proposed to evaluate the possibility of differential kinetic analysis.The R_d valuebetween the neighbouring lanthanide ions first increases and then decreases along with increasing atomic number,so that the middle and heavy rare earth mixture(such as Sm-Gd and Gd-Y)are ideal systems for thedifferential rate kinetic analysis. 相似文献
87.
在叙述国内外稀土市场基本情况的基础上,指出我国稀土行业目前存在的问题,并提出了发展湖南稀土工业的建议。 相似文献
88.
OrganicMetalogenyofWeatheringCrustREDepositChenZhicheng(陈志澄)(GuangdongColegeofPharmacy,Guangzhou510224,China)YuShoujun(俞受均金)... 相似文献
89.
Virtual prototyping is a useful approach for refining requirements for complex designs. However, the use of virtual reality (VR) technology can cause usability problems that can be interpreted as false positive requirements errors. The immersive scenario-based requirements engineering (ISRE) method guides the analysis of problems encountered during the testing of virtual prototypes and helps assign causes to either genuine requirements defects or to usability issues with VR technology. The method consists of techniques for walkthrough testing, testing with users, causal analysis of observed problems and the design of scenario-based analysis sessions. The method is described and its use illustrated with a case study of validating requirements for an aircraft maintenance application. 相似文献
90.
Both software organisations and the academic community are aware that the requirements phase of software development is in need of further support. We address this problem by creating a specialised Requirements Capability Maturity Model (R-CMM1). The model focuses on the requirements engineering process as defined within the established Software Engineering Institute’s (SEI’s) software process improvement framework. Our empirical work with software practitioners is a primary motivation for creating this requirements engineering process improvement model. Although all organisations in our study were involved in software process improvement (SPI), they all showed a lack of control over many requirement engineering activities.This paper describes how the requirements engineering (RE) process is decomposed and prioritised in accordance with maturity goals set by the SEI’s Software Capability Maturity Model (SW CMM). Our R-CMM builds on the SEI’s framework by identifying and defining recommended RE sub-processes that meet maturity goals. This new focus will help practitioners to define their RE process with a view to setting realistic goals for improvement.Sarah Beecham is a research fellow in the Department of Maths and Computing in The Open University in the UK. She is currently working on the EPSRC funded CRESTES project () looking into modelling resource estimation for long-lived software. She has recently completed her PhD for a program of work entitled “A Requirements-based Software Process Maturity Model”. Current research interests are in estimation for software evolution and maintenance and in the general areas of software process improvement. Her particular research interests are in empirical methods in software engineering and requirements engineering.Tracy Hall leads the Systems & Software Research Group in the Department of Computer Science at the University of Hertfordshire. She specialises in the empirical investigation of technical and non-technical issues within software engineering. During the past ten years Tracy has successfully collaborated with many companies on a variety of research projects. She is very active in the Empirical Software Engineering community and is regularly invited to talk about empirical methods both in the UK and abroad. Tracy is an accomplished researcher having published over twenty high quality journal papers.Austen Rainer Austen Rainer is a senior lecturer at the University of Hertfordshire. He studied for his PhD at Bournemouth University, in conjunction with IBM Hursley Park. His current research interests include open source software development, longitudinal case study research, and the credibility of empirical evidence for researchers and software practitioners. 相似文献