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51.
利用离散小波变换获得青藏高原布格重力异常不同尺度的总水平梯度(HGM)和横向、纵向、对角分量平方和的平方根(HVDM)图像。结果表明:1)4、5阶小波细节之和的HGM高值区域存在于尼泊尔喜马拉雅地区、喜马拉雅东构造结和阿尔金断裂带中段,即青藏高原周缘较为活跃的构造带;2)尼泊尔喜马拉雅地区和阿尔金断裂带西段存在5阶小波逼近高值HGM,较高值HGM带呈现环青藏高原形态,反映了青藏高原与周缘构造块体地壳深度变化和岩石圈地幔顶部物质性质的差异性变化特征;3)HVDM高值带分布于喜马拉雅地区、喜马拉雅东构造结地区、阿尔金断裂带和龙门山断裂带,体现了青藏高原周缘构造带形态特征;4)2015尼泊尔Ms8.1地震发生在地壳深部的HGM高-低-高分布形态的低值区和HVDM高值带的边界,是印度板块和欧亚板块持续汇聚及周缘大型走滑断裂带的调节作用、累积能量释放的结果。 相似文献
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Jürgen Knödlseder Peter von Ballmoos Filippo Frontera Angela Bazzano Finn Christensen Margarida Hernanz Cornelia Wunderer 《Experimental Astronomy》2009,23(1):121-138
The gamma-ray imager (GRI) is a novel mission concept that will provide an unprecedented sensitivity leap in the soft gamma-ray
domain by using for the first time a focusing lens built of Laue diffracting crystals. The lens will cover an energy band
from 200–1,300 keV with an effective area reaching 600 cm2. It will be complemented by a single reflection multilayer coated mirror, extending the GRI energy band into the hard X-ray
regime, down to ∼10 keV. The concentrated photons will be collected by a position sensitive pixelised CZT stack detector.
We estimate continuum sensitivities of better than 10 − 7 ph cm − 2s − 1keV − 1 for a 100 ks exposure; the narrow line sensitivity will be better than 3 × 10 − 6 ph cm − 2s − 1 for the same integration time. As focusing instrument, GRI will have an angular resolution of better than 30 arcsec within
a field of view of roughly 5 arcmin—an unprecedented achievement in the gamma-ray domain. Owing to the large focal length
of 100 m of the lens and the mirror, the optics and detector will be placed on two separate spacecrafts flying in formation
in a high elliptical orbit. R&D work to enable the lens focusing technology and to develop the required focal plane detector
is currently underway, financed by ASI, CNES, ESA, and the Spanish Ministery of Education and Science. The GRI mission has
been proposed as class M mission for ESAs Cosmic Vision 2015–2025 program. GRI will allow studies of particle acceleration
processes and explosion physics in unprecedented detail, providing essential clues on the innermost nature of the most violent
and most energetic processes in the universe.
All authors are on behalf of a large international collaboration
The GRI mission has been proposed as an international collaboration between (in alphabetical order) Belgium (CSR), China (IHEP,
Tsinghua Univ.), Denmark (DNSC, Southern Univ.), France (CESR, APC, ILL, CSNSM, IAP, LAM), Germany (MPE), Ireland (UCD School
of Physics), Italy (INAF/IASF Rome, Bologna, Milano, Palermo; INAF/OA Brera, Roma; UNIFE, CNR/IMEM), Poland (NCAC), Portugal
(Combra Univ., Evora Univ.), Russia (SINP, MSU, Ioffe Inst.), Spain (IEEC-CSIC-IFAE, CNM-IMB), the Netherlands (SRON, Utrecht
Univ.), Turkey (Sabanci Univ.), United Kingdom (Univ. of Southampton, MSSL, RAL, Edinburgh Univ.), and the United States of
America (SSL UC Berkeley, Argonne National Lab., MSFC, GSFC, US NRL). 相似文献
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2015-2030年中国新型城镇化发展及其资金需求预测 总被引：2，自引：2，他引：0
未来的新型城镇化如何发展是政府和社会各界广泛关注的问题。本文利用时间序列预测法、Logistic曲线估算法、复合函数估算法及建立模型等方法,借助SPSS和ArcGIS平台,对2015-2030年全国及31个省市区的城镇化发展进行预测研究。根据预测结果,探讨了中国城镇化率70.12%背景下的城镇化质量空间分异状况,估算了2015-2030年全国及31个省市区新型城镇化建设的资金需求。结果表明：① 2015-2030年,中国人口、城镇化率将分别达到14.45亿和70.12 %;② 2015-2030年,人口红利将不存在,会承受人口总量最大的压力。城镇人口自身再生产7016.26万,需要城镇化的农村人口为31567.96万,城市人口净增加3.86亿;③ 2015-2030年,从中国城镇化率时—空分异变化来看,各省市区城镇化率发展的差异性很大,但都在增长,而且增长的幅度空间差异性很大。从城镇化质量来看,也存在着极大的差异,不仅如此,有些省区其城镇化质量与经济社会不相协调;④ 2015-2030年,全国新型城镇化建设所需资金105.38万亿元,而各省市区的资金需求并不均衡,差别极大,资金需求最多的是广东,最少的是西藏,相差148.09倍。最后,就新型城镇化发展及投资建设等方面提出了相关建议。 相似文献
54.
Luke Kemp 《Climate Policy》2016,16(8):1011-1028
The issue of US ratification of international environmental treaties is a recurring obstacle for environmental multilateralism, including the climate regime. Despite the perceived importance of the role of the US to the success of any future international climate agreement, there has been little direct coverage in terms of how an effective agreement can specifically address US legal participation. This article explores potential ways of allowing for US legal participation in an effective climate treaty. Possible routes forward include the use of domestic legislation such as section 115 (S115) of the Clean Air Act (CAA) and the use of sole–executive agreements, instead of Senate ratification. Legal participation from the US through sole–executive agreements is possible if the international architecture is designed to allow for their use. Architectural elements such as varying legality and participation across an agreement (variable geometry) could allow for the use of sole–executive agreements. Two broader models for a 2015 agreement with legal participation through sole–executive agreements are constructed based upon these options: a modified pledge and review system and a form of variable geometry composed of number of opt-out, voting-based protocols on specific issues accompanied by bilateral agreements on mitigation commitments with other major emitters through the use of S115 and sole–executive agreements under the Montreal Protocol and Chicago Convention (‘Critical Mass Governance'). While there is no single solution, Critical Mass Governance appears to provide the optimum combination of tools to effectively allow for US legal participation whilst ensuring an effective treaty.
Policy relevance
This article provides some recommendations on how to create an effective, legally binding treaty that allow for US legal participation without Senate approval. Given the recent election of a Republican majority in the US Senate and Congress, increasing willingness of the President to utilize his executive powers, as well as a strong shift in negotiations to appease US interests, the insights of this research are timely and relevant to delegations and other United Nations Framework Convention on Climate Change (UNFCCC) actors. It will also be of use to domestic US actors involved with climate policy by illustrating how to allow for effective and sustainable US multilateral engagement that bypasses domestic political gridlock. 相似文献
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基于2015年尼泊尔地震序列的破裂模型及均匀弹性半空间模型,计算了该地震序列传递到中国西藏境内发生在定日县地震和聂拉木县地震的应力.2015年尼泊尔地震序列导致定日县地震和聂拉木地震节面和滑动方向的库仑应力增加(2~3)×103 Pa和(2.4~3.1)×105 Pa,表明这两个地震受到尼泊尔地震序列的触发.其次,我们计算了2015年尼泊尔地震序列在中国大陆及其附近主要活动断层上产生的库仑应力变化.喜马拉雅主山前逆冲断裂和青藏高原内部的拉张正断层上的库仑应力有较大的增加,而青藏高原的走滑断裂,如阿尔金断裂、东昆仑断裂、玉树玛曲断裂、班公错断裂西部、嘉黎断裂的库仑应力有较大的降低.天山南北两侧的断裂库仑应力降低.而华北及东北、华南地区的库仑应力变化几乎可以忽略不计.最后,计算了该地震序列造成的水平应力变化.水平面应力在2015年尼泊尔地震序列北向(青藏高原大部和新疆区域)增加(拉张),而在地震序列东侧的西藏南部和川滇地区南部降低(压缩),在华北和东北仅有少许增加,在华南地区有少许降低.在中国西部,主压应力表现为以2015年地震序列为圆心的向外辐射状,而主张应力方向与同心圆切线方向大体一致.水平主压应力方向在东北地区为北东向,在华北地区为北东东向,在华南地区为南东东向.这种模式与现今构造应力场方向相似,表现了2015尼泊尔地震序列所代表的印度板块和欧亚板块的碰撞是中国大陆构造变形的主要动力来源. 相似文献