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991.
《Climate Policy》2013,13(3):277-292
California is considering the adoption of a cap-and-trade regulatory mechanism for regulating the greenhouse gas emissions from electricity and perhaps other industries. Two options have been widely discussed for implementing cap-and-trade in the electricity industry. The first is to regulate the emissions from electricity at the load-serving entity (LSE) level. The second option for implementation of cap-and-trade has been called the ‘first-seller’ approach. Conceptually, under first-seller, individual sources (i.e. power plants) within California would be responsible for their emissions, as with traditional cap-and-trade systems. Emissions from imports would be assigned to the ‘importing firm’. An option that has not been as widely discussed is to implement a pure source-based system within California, effectively excluding imports from the cap-and-trade system altogether. This article examines these three approaches to implementing cap-and-trade for California's electricity sector. The article discusses many of the issues relating to measurement and the impacts on bidding and scheduling incentives that are created by the various regulatory regimes. 相似文献
992.
The discovery of the Crab Nebula as the first source of TeV gamma rays in 1989, using the technique of ground-based imaging air Cherenkov telescope, has marked the birthday of observational gamma astronomy in very high energy range. The team led by Trevor Weekes, after twenty years of trial and error, success and misfortune, step-by-step improvements in both the technique and understanding of gamma shower discrimination methods, used the 10 m diameter telescope on Mount Hopkins in Arizona, and succeeded measuring a 9σ signal from the direction of Crab Nebula. As of today over 160 sources of gamma rays of very different types, of both galactic and extra-galactic origin, have been discovered due to this technique. This is a really fast evolving branch in science, rapidly improving our understanding of the most violent and energetic sources and processes in the sky.The study of these sources provides clues to many basic questions in astrophysics, astro-particle physics, physics of cosmic rays and cosmology. Today’s telescopes, despite the young age of the technique, offer a solid performance. The technique is still maturing, leading to the next generation large instrument. This article is devoted to outlining the milestones in a long history that step-by-step have made this technique emerge and have brought about today’s successful source hunting. 相似文献
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995.
Adjoint Assimilation in Marine and an Example of Application 总被引:1,自引:1,他引:0
XU Qing LIU Yuguang and LU Xianqing Physical Oceanography Laboratory Ocean University of China Qingdao P.R.China 《中国海洋大学学报(英文版)》2005,4(1):14-20
This paper aims at a review of the work carried out to date on the adjoint assimilation of data in marine ecosystem models since 1995. The structure and feature of the adjoint assimilation in marine ecosystem models are also introduced. To illustrate the application of the adjoint technique and its merits, a 4-variable ecosystem model coupled with a 3-D physical model is established for the Bohai Sea and the Yellow Sea. The chlorophyll concentration data derived from the SeaWiFS ocean colour data are assimilated in the model with the technique. Some results are briefly presented. 相似文献
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997.
徐琼 《成都信息工程学院学报》2006,21(1):110-112
证明了由任意a尺度正交单尺度函数和任意一组正交滤波器生成a尺度r重正交多尺度函数的一个充分必要条件,并给出了a尺度r重正交多小波的一种构造方法. 相似文献
998.
讨论了一类实解析函数在极小(大)值点附近存在凸(凹)性区间的条件,得到了如下主要结果:若非常值函数y=f(x)在x0处取得极小(大)值,且在x0的某一邻域G内实解析的。则存在x0的一小邻域G^*包含G,使得原函数在G^*上为凸(凹)的。 相似文献
999.
We present the first CCD photometric UBVRI observations of the not-so-well-studied open cluster NGC 1624 (OCl 403, Cr 53; α2000 = 04 h 40 m 36 s; δ2000 = + 50˚ 27′ 42″ Trumpler class = I 2 p N). This cluster was observed on 01 February 2004 with the 2 m Himalayan Chandra Telescope at Hanle using a LN2 cooled 2k × 2k CCD. The cluster presents differential reddening with E(B-V) values ranging from 0.70 to 0.90 mag, which could be attributed to the presence of the HII region wherein the cluster is embedded. It is found to be at a distance of 6.025 ± 0.5 kpc and the age of this cluster is estimated to be ∼3.98 × 106 years. In view of these parameters, it can be considered as a young enough cluster located in the direction of the Perseus constellation with the galactic coordinates of l = 155˚.35 and b = + 02 ˚.58. Thus it could also be used as a suitable candidate for tracing the Outer Perseus spiral arm of our Galaxy. The initial mass function slope is derived as 1.65 ± 0.25 by applying the corrections for field star contamination and data incompleteness. This is in good agreement with the Salpeter value within the limits of errors. 相似文献
1000.
基于CC的防火墙安全功能分析 总被引:1,自引:0,他引:1
防火墙是网络安全的核心手段。依据基于CC(Common Criteria)制订的国家标准——包过滤防火墙安全技术要求和应用级防火墙安全技术要求,提出每项安全功能要求对应的实际安全措施,并分析当前防火墙未实现的安全功能要求。 相似文献