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《Energy Policy》2015
Rapid diffusion of renewable energy sources (RES) in the electricity power sector is crucial if the EU wants to fulfill its 2050 CO2 reduction commitments. For this reason, identifying and alleviating all barriers that hinder the development of RES is necessary to the successful deployment of these technologies. This paper discusses the main barriers in the diffusion of wind and photovoltaic (PV) solar power in the Greek electricity sector by drawing on the literature of technological innovation systems and system functions. Furthermore, we provide an explanation of the different diffusion rates between the two technologies. Inadequate financial resources, low grid capacity, delays in the issuance of building permits, opposition from local communities to the construction of wind farms and the lack of a stable institutional framework are among the most important barriers that inhibit the diffusion of the wind and PV solar power. The nature of the barriers identified in this study calls for policy intervention. 相似文献
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In modern cloud data centers, reconfigurable devices (FPGAs) are used as an alternative to Graphics Processing Units to accelerate data-intensive computations (e.g., machine learning, image and signal processing). Currently, FPGAs are configured to execute fixed workloads, repeatedly over long periods of time. This conflicts with the needs, proper to cloud computing, to flexibly allocate different workloads and to offer the use of physical devices to multiple users. This raises the need for novel, efficient FPGA scheduling algorithms that can decide execution orders close to the optimum in a short time. In this context, we propose a novel scheduling heuristic where groups of tasks that execute together are interposed by hardware reconfigurations. Our contribution is based on gathering tasks around a high-latency task that hides the latency of tasks, within the same group, that run in parallel and have shorter latencies. We evaluated our solution on a benchmark of 37500 random workloads, synthesized from realistic designs (i.e., topology, resource occupancy). For this testbench, on average, our heuristic produces optimum makespan solutions in 47.4% of the cases. It produces acceptable solutions for moderately constrained systems (i.e., the deadline falls within 10% of the optimum makespan) in 90.1% of the cases. 相似文献
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《The Journal of Strategic Information Systems》2022,31(2):101719
The paper develops a conceptual framework to study the constructs of information technology (IT)-supported value co-creation and co-destruction through shared processes of social interaction and resource integration as mediated by IT and embedded in interactive value formation practices. In particular, the elements of social interaction and resource integration are identified, and the role of IT is discussed. We conduct a systematic literature review and analyze the data using the service system perspective. Our research contributes by identifying the constructs of value-creating phenomena enabled by IT from the service system perspective and presenting a research agenda for further studies. 相似文献
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Resource allocation strategies in virtualized data centers have received considerable attention recently as they can have substantial impact on the energy efficiency of a data center. This led to new decision and control strategies with significant managerial impact for IT service providers. We focus on dynamic environments where virtual machines need to be allocated and deallocated to servers over time. Simple bin packing heuristics have been analyzed and used to place virtual machines upon arrival. However, these placement heuristics can lead to suboptimal server utilization, because they cannot consider virtual machines, which arrive in the future. We ran extensive lab experiments and simulations with different controllers and different workloads to understand which control strategies achieve high levels of energy efficiency in different workload environments. We found that combinations of placement controllers and periodic reallocations achieve the highest energy efficiency subject to predefined service levels. While the type of placement heuristic had little impact on the average server demand, the type of virtual machine resource demand estimator used for the placement decisions had a significant impact on the overall energy efficiency. 相似文献
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对风景名胜区和自然保护区实行特许经营的讨论 总被引:1,自引:0,他引:1
介绍了国外国家公园实行特许经营的经验,阐述特许经营的基本特征和实行特许经营的一些基本原则。揭示在我国的一些风景名胜区和自然保护区实行的“特许经营”所具有的整体性、垄断性和不公开、不透明等缺陷,分析了以经营等同于管理、以经营取代管理给国家级风景名胜区和自然保护区资源保护管理带来的种种弊端。风景名胜区和自然保护区的特许经营问题,需要进一步的理论研究、个案调查,从而推动立法进程。 相似文献
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It is well known that boric acid exhibits various toxic effects on plant, animal and human beings even at very low concentrations. Thus, the development of boron-removal technique from wastewater has been intensively investigated. In this study, a new hydrothermal treatment technique was developed to recover boron as recyclable precipitate Ca(2)B(2)O(5).H(2)O from aqueous solutions. As a result, it was found that the hydrothermal treatment using calcium hydroxide as a mineralizer converted boron in the aqueous media effectively into calcium borate, Ca(2)B(2)O(5).H(2)O. In the optimal hydrothermal condition, more than 99% of boron was collected from the synthetic wastewater of 500 ppm. Thus, the present hydrothermal treatment in the presence of calcium hydroxide is recommended as one of the effective techniques to recover boron from aqueous media. 相似文献
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西部山地城镇的生态化发展思考 总被引:2,自引:0,他引:2
经济与产业结构不合理、缺乏有效的产业支撑和经济手段、自然生态环境脆弱等是当前西部山地城镇化面临的主要问题.应以生态效益的最大化和山地环境的可持续性为前提,结合当前西部山地经济发展的实际情况,采取适合其生态产业发展的城镇化模式,使山地城镇化成为促进山地传统农业经济向生态农业经济转变的核心推动力. 相似文献
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