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61.
Utilizing information from plate tectonics characteristics, volcanic activities, and geothermal anomaly, this paper identifies areas where hot dry rock (HDR) may exist as potential geothermal resource in China. Further investigations are also carried out in the paper based on results from regional tectonics, volcanic geology and lithology, as well as data from geothermal displays, geochemistry, geophysics, and shallow borehole temperature measurements. The study reveals several promising areas of HDR geothermal resource in China, including Tengchong of Yunnan province, Qiongbei of Hainan province, Changbaishan of Jilin province, Wudalianchi of Heilongjiang province, and the Southern Tibet area. A 3D static heat conduction model was developed to study the underground temperature gradient characteristics of the Rehai geothermal field in Tengchong and the Yangbajing geothermal field in Tibet. The model adopted is a geological block 10 km deep from the ground surface and 50 km wide in each of the horizontal directions (2500 km2 area). The numerical simulation results in evaluations on the quantities of the HDR geothermal resource in Rehai and Yangbajing geothermal fields. The paper shows that there is abundant HDR geothermal resource with large exploitation value in China. If developed with a power capacity of 1×108 kW, the Rehai and Yangbajing fields along would be able to generate electricity for 1560 years. 相似文献
62.
上世纪后半期以来,世界油价变化已经历了4个阶段:第一阶段为二战后到1973年平稳的特低油价期,第二阶段为以两次石油危机为主体的油价剧烈动荡期,第三阶段为1986~1999年起伏的较低油价期,第四阶段为2000~2013年剧烈起伏的高油价期。此次油价下跌意味着进入了第五阶段——动荡中的油价较低期。它起因于国际石油市场供大于需的积累,雄厚的剩余产能和过量的石油储备是其两个明显标志;肇发于以沙特为首的海合会国家不愿看到自己的市场份额被侵占而不再减产保价,同时又叠加了世界经济疲软、美元指数走高的市场形势影响。市场供需将在新的低油价下达到新的平衡。低油价将首先对财政油价高且国内经济低迷的石油输出国产生强烈冲击,也将影响到生产成本低的石油输出国;而对石油消费国则是利大于弊,并将促进世界经济的回升;对于一些高成本的油气生产也会产生明显影响,最终将促使世界石油市场格局发生重大变化。低油价期的再次出现,还会使以化石能源为主体的时代比某些人预期的要长,但这也为多种新能源的发展争取了时间,从而使其更从容更健康地走向成熟。 相似文献
63.
DiscussionontheNetworkMethodforCalculatingRadiantInterchangeWithinanEnclosure¥H.J.Kang;W.Q.Tao(SchoolofEnergyandPowerEngineer... 相似文献
64.
Dong-Ki Kang Fawaz Al-Hazemi Seong-Hwan Kim Min Chen Limei Peng Chan-Hyun Youn 《Mobile Networks and Applications》2016,21(5):793-805
As cloud computing models have evolved from clusters to large-scale data centers, reducing the energy consumption, which is a large part of the overall operating expense of data centers, has received much attention lately. From a cluster-level viewpoint, the most popular method for an energy efficient cloud is Dynamic Right Sizing (DRS), which turns off idle servers that do not have any virtual resources running. To maximize the energy efficiency with DRS, one of the primary adaptive resource management strategies is a Virtual Machine (VM) migration which consolidates VM instances into as few servers as possible. In this paper, we propose a Two Phase based Adaptive Resource Management (TP-ARM) scheme that migrates VM instances from under-utilized servers that are supposed to be turned off to sustainable ones based on their monitored resource utilizations in real time. In addition, we designed a Self-Adjusting Workload Prediction (SAWP) method to improve the forecasting accuracy of resource utilization even under irregular demand patterns. From the experimental results using real cloud servers, we show that our proposed schemes provide the superior performance of energy consumption, resource utilization and job completion time over existing resource allocation schemes. 相似文献
65.
Woo-Tag Kang Jeong-Seok Kim Kang-Yoon Lee Yoo-Cheol Shin Tae-Heon Kim Yong-Jik Park Jong-Woo Park 《Electron Device Letters, IEEE》2000,21(1):9-11
The leakage current characteristics of the cobalt silicided NMOS transistors with a junction depth of 800 Å have been studied. In order to minimize the junction leakage current, the thickness of the CoSi2 layer should he controlled under 300 Å and the Si surface damage induced by the gate spacer etch should be minimized. The post furnace annealing after the second silicidation by the rapid thermal annealing (RTA) process also affected the leakage current characteristics. The gate induced drain leakage (GIDL) current was not affected by the lateral encroachment of CoSi2 layer into the channel direction when the gate spacer length was larger than 400 Å 相似文献
66.
In this paper, on-surface measured equation of invariance (OSMEI) method is implemented for capacitance extraction of electrostatic multiconductor interconnect problems. OSMEI uses the same mesh as that in method of moments (MoM), but generates highly sparse matrices rather than a full matrix. In comparison with “standard” MEI which contains a few finite difference (FD) or finite element (FE) mesh layers, the number of unknowns and the computation memory can be saved. For each OSMEI equation in the multiconductor interconnects, a given node on a given conductor is forced into coupling with the few adjacent nodes on conductor itself and the few sampled nodes on other conductors. Thus, the system sparse matrices can be generated. The convergent behavior of the capacitance with the number of the nodes in the OSMEI equations has been widely investigated, Numerical examples of the capacitance extraction for two-dimensional (2-D) and three-dimensional (3-D) multiconductor interconnects show that the computing errors are within 24%. The OSMEI method may become a powerful technique for the more complex interconnect problems 相似文献
67.
In this paper, we investigate the effects of the spatial fading correlation on the performance of a multiple-input multiple-output (MIMO) adaptive antenna system with optimum combining (OC) in the presence of multiple cochannel interferers over a correlated Rayleigh fading channel. Based on the Khatri's distribution functions of quadratic forms in complex Gaussian random matrices, we develop a unified determinant representation of those joint eigenvalue distributions. Taking into account the spatial correlation among the antenna elements at the transmitter or receiver, we derive the closed-form formulas for the probability density function and outage probability of the maximum output signal-to-interference ratio (SIR) in an interference-limited MIMO-OC system. Furthermore, the average output SIR and error probability are also investigated. From numerical examples, we show that a new theoretical approach gives a simple and accurate way to assess the performance of the MIMO-OC system over arbitrarily correlated fading channels 相似文献
68.
巡航导弹景象匹配算法适应性研究 总被引:6,自引:1,他引:6
文章针对景象匹配制导的需求,研究了去均值归一化、基于直方图拉伸和基于局部平滑相关匹配算法,分析了算法的适应性、计算量和实时性等,比较了每种算法的优缺点.结合巡航导弹的使用,讨论了影响匹配结果的一些基本的、可能的因素,主要是环境因素.用三种分辨率的图像作了大量的实验,针对这些算法的匹配概率及地物适应性等方面进行了编程验证和综合分析,给出了有关结论. 相似文献
69.
石家庄电业局采用SR500-S系统,解决了下辖17个县局和变电站的通信与数据传输,为此介绍了系统的组成、工作原理、接口方式及特点,并展望了1对N点微波通信的发展。 相似文献
70.
The goal of telecommunication may be to enable the participants in distant places to communicate with each other in an environment as if they were in the same room. This paper introduces the reason why realistic audio display is useful in telecommunication, reviews some approaches to its implementation, and proposes an audio teleconference model which realizes a two-way telecommunication with realistic sensations using binaural and auralization techniques. 相似文献