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排序方式: 共有193条查询结果,搜索用时 593 毫秒
61.
研究了空间铷钟和被动型氢钟的地面批量和寿命试验测试结果,以及卫星在轨试验所达到的最新性能结果。基于这些星载钟的试验结果,对全球卫星导航系统的地面时间站的关键设备及其相关算法作了简要描述,并介绍了一种新颖的在轨技术,即从星载原子钟组(ONCLE)直接产生高度稳健的时间频率信号。 相似文献
62.
In this paper, we compare different policy incentives for overcoming investment uncertainties that are typical for low-carbon technologies prior to their commercialisation, some of which may be attributable to market failures. The paper focuses on the particular case of carbon capture and storage (CCS) technologies and conducts a qualitative multi-criteria analysis of different public policy support schemes for CCS demonstration to evaluate their suitability. The assessed schemes include mandatory CCS, emission performance standards and several different financial incentives (in addition to the European Union Emission Trading Scheme). Based on the available literature and on experience in the UK and Germany with promotion instruments for low-carbon technologies, the results of our analysis suggest that two alternative schemes, a CCS bonus incentive or a carbon dioxide (CO2) price guarantee, perform best in comparison with the other assessed instruments. While they reduce the uncertainty of CCS investments in the face of low European Union Allowance prices, they also avoid significant adverse impacts on operational and investment decisions in electricity markets. 相似文献
63.
胶东望儿山金矿床构造-热事件时序:野外地质证据 总被引:7,自引:0,他引:7
望儿山金矿床是位于山东招远-莱州金矿区西部焦家金矿田内的一个大型金矿床,矿区内断裂构造发育,总体走向为NNE-NE,其控制了矿区蚀变带的展布;矿床由石英脉型矿体和蚀变岩型矿体组成,两者均严格受断裂构造的控制。通过对望儿山金矿床的野外地质考察,根据野外观察到的构造性质、切割关系以及地质体的穿插关系认为矿区内构造→热事件时... 相似文献
64.
杜康宁 《成都信息工程学院学报》1994,(3)
利用Z-80实时时钟制作老化产品的计时器,具体通过Z-80TP801单板机控制来实现,使老化产品时间更加准确。除了计时、分、秒外,还可以计天(日),计时的时间可在显示器上直接观察,使人们了解老化产品时间是否已到,从而增加老化产品时间的精确性。 相似文献
65.
A successful piece of applied research will not only influence the related problem perception within the scientific community, but also lead to much better understanding of a complex challenge, including the delivery of solutions. Ideally it may contribute significantly to reducing possible risk situations for people and/or the natural environment. In short, a successful study will have a broader impact beyond the sphere of science. Planning, timing, funding, networking, communication, and interdisciplinarity are identified as key aspects for a successful project and are being examined in their scope and boundary conditions, while not neglecting the particular role of local and regional people and authorities.Defining what makes a successful environmental geochemical study is clearly based upon experience and evidence found, and not upon any particular theoretical concept. Here, experience is drawn from the outcome of many projects and specifically first-hand from the complex ARSENEX project in Minas Gerais, Brazil. Against the backdrop of both perceived and real arsenic contamination of environmental compartments, including local people, all subsequent project steps and proposals were set up using a three-prong approach that sought to a) understand the processes, b) educate and inform the public and all other stakeholders and c) remediate the situation. 相似文献
66.
In this article the problem of credible commitment in carbon policy is discussed. Investors favour long-term predictability of the policy, but without any external enforcement mechanisms a commitment made by a government can be withdrawn, leading to scepticism and lack of credibility. This results in increased market risks and investment hold-up. Regulatory uncertainty stems from (i) strategic interactions between government and firms, (ii) potential learning about climate damage and abatement cost and (iii) political volatility. Although commitment to future policy encourages private investment, it also imposes costs in the form of reduced flexibility to accommodate new information or preferences. The article reviews devices that may help policy makers raise the level of commitment while also leaving some room for flexible adjustments. In particular, legislation of a long-term governance framework, delegation to an independent carbon agency and securitization of investors' stakes in emission markets offer palliative approaches. 相似文献
67.
基于人本原理的旅游社区居民激励机制的构建 总被引:1,自引:0,他引:1
社区居民的支持直接关乎地方的旅游形象甚至关乎旅游业发展成功与否。从人本原理和双因素理论出发,得出:要调动和维持居民的积极性,首先要注意诸如让居民监督旅游业发展、为社区建设服务等保健因素,以防止不满情绪的产生。但更重要的是要利用诸如参与规划制定、参与管理决策、鼓励居民持股、为居民提供培训和就业机会、培养居民自豪感等激励因素去激发居民的工作热情,努力工作,创造奋发向上的局面,因为只有激励因素才会增加居民的工作满意感。并且认为在今后的旅游业发展实践中,应开辟新的途径,让居民真正参与到旅游业的发展中并从中受益。 相似文献
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