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991.
《Marine Policy》2015
To address long-standing allocation conflicts between the Pacific halibut commercial fishing sector and recreational charter (for-hire) sector in Alaska, an Alaska halibut catch sharing plan (CSP) is being implemented in 2014 that has a provision allowing the leasing of commercial individual fishing quota to recreational charter businesses. This one-way inter-sectoral trading allows for the charter sector to increase its share of the total allowable catch while compensating commercial fishermen. This type of catch shares program is novel in fisheries. In this paper, the literature on non-fisheries tradable permit programs (TPPs) that have similarities to the Alaska halibut CSP program is examined. Several successful TPPs are discussed, including ones from emissions trading programs, water quality trading programs, water markets, and transferable development rights programs. They are then evaluated in terms of their similarities and differences to the Alaska CSP program. Characteristics not part of the current CSP that other TPPs have used and that may increase the likelihood for the CSP to be effective in achieving its primary goals (if they are implemented) are identified, such as allowing more flexible transfers (e.g., internal transfers), intertemporal banking, cooperative structures, and multi-year leasing. 相似文献
992.
开挖与支护应力路径下硬岩破坏过程的真三轴与声发射试验研究 总被引:2,自引:2,他引:0
针对硬岩的脆性破坏问题,利用真三轴和声发射(AE)试验系统研究了灰岩试样在不同应力路径和应力水平下的力学特征与变形破坏机理、AE活动特征及能量释放规律。试验研究表明:(1)开挖卸荷应力路径下,试样强度受卸荷作用影响较大,且随中间主应力呈区间性变化,试样以脆性劈裂破坏为主;(2)开挖卸荷+支护的应力路径下,支护力显著改善了岩石的力学性质,破坏形式以张剪性破坏为主;(3)试样AE活动过程可以分为三个活跃期(裂隙压密阶段、卸荷阶段和失稳-破坏阶段)和两个相对平静期(弹性变形阶段和微破裂稳定发展阶段),AE信号表征参数“absolute energy”作为能量度量指标能够较好地定量描述和研究硬岩的脆性破坏过程。试验结果和许多工程开挖和支护过程中岩体的力学行为和支护作用类似,可为工程现场开挖支护设计提供试验依据和有益指导。 相似文献
993.
L. V. Didkovsky D. L. Judge A. R. Jones S. Wieman B. T. Tsurutani D. McMullin 《Astronomische Nachrichten》2007,328(1):36-40
The solar irradiance in the Extreme Ultraviolet (EUV) spectral bands has been observed with a 15 s cadence by the SOHO Solar EUV Monitor (SEM) since 1995. During remarkably intense solar flares the SEM EUV measurements are saturated in the central (zero) order channel (0.1–50.0 nm) by the flare soft X‐ray and EUV flux. The first order EUV channel (26–34 nm) is not saturated by the flare flux because of its limited bandwidth, but it is sensitive to the arrival of Solar Energetic Particles (SEP). While both channels detect nearly equal SEP fluxes, their contributions to the count rate is sensibly negligible in the zero order channel but must be accounted for and removed from the first channel count rate. SEP contribution to the measured SEM signals usually follows the EUV peak for the gradual solar flare events. Correcting the extreme solar flare SEMEUV measurements may reveal currently unclear relations between the flare magnitude, dynamics observed in different EUV spectral bands, and the measured Earth atmosphere response. A simple and effective correction technique based on analysis of SEM count‐rate profiles, GOES X‐ray, and GOES proton data has been developed and used for correcting EUV measurements for the five extreme solar flare events of July 14, 2000, October 28, November 2, November 4, 2003, and January 20, 2005. Although none of the 2000 and 2003 flare peaks were contaminated by the presence of SEPs, the January 20, 2005 SEPs were unusually prompt and contaminated the peak. The estimated accuracy of the correction is about ±7.5% for large X‐class events. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
994.
罗源湾区域入海非点源污染COD排放量估算 总被引:2,自引:0,他引:2
根据汇水流向,借助GIS进行罗源湾汇水区的划分;在ENVI软件下利用遥感分析技术提取土地利用类型;结合研究区域内主要溪流的水质监测结果和土地利用现状,利用反推法计算出农田污染单位面积COD负荷.在此基础上,采用排污系数法和单位面积污染负荷法分别计算出各汇水区农村生活污水、畜禽养殖、农田和村镇建设用地降雨径流的COD排放量.结果表明罗源湾入海非点源污染COD总排量为11 446.44t/a,其中农村生活污水的COD排放量最大,约占38.9%,其次是畜禽养殖、农田和村镇建设用地降雨径流污染.最后提出非点源污染控制的建议. 相似文献
995.
研究了高频电波加热电离层实验期间电子能量分布函数,利用美国HAARP和欧洲EISCAT实验中630.0 nm、557.7 nm与844.6 nm等气辉辐射测量结果,给出了在红光与绿光强度比值小于10和比值大于等于10两种情况下电子能量分布函数表达式,在3~100 eV电子能量范围内,分段幂指数因子随电子能量的增加而下降,并利用获得电子能量分布函数对其他电离层加热期间气辉辐射进行计算,红光与绿光辐射强度之比与实验测量结果相符,从而验证了获得的电子能量分布函数. 相似文献
996.
EXPERIMENT STUDY ON ACOUSTIC EMISSION,MICROSEISM AND CHARGE INDUCTION DURING FRACTURE PROCESS OF GRANITE WITH FAULT ZONE UNDER UNIAXIAL COMPRESSION
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As the rock samples will produce abnormal signals of acoustic emission, microseismic and charge signals under external loading, the waveform comprehensive monitoring devices are used to synchronously monitor acoustic emission, microseismic and charge signals during the deformation and failure process of granite with fault zone under uniaxial compression. The results show that, the granite with fault zone has obvious synchronous precursory signals of acoustic emission, microseism and charge induction in the elastic deformation stage, and has high amplitude synchronous precursory signals in the instability destruction stage. The influence of fault zone on granite samples strength is remarkable, and the uniaxial compressive strength of samples with the fault zone is greatly reduced. With the angle of the fault zone decreasing, the uniaxial compressive strength of the specimens is reduced, the samples are more liable to instability and the energy of instability destruction is greater. With the fault zone angle of granite samples decreasing, the acoustic emission, microseismic and charge induction signals increase in the deformation and failure process of samples. The samples stress decreases when the acoustic emission, microseismic and charge induction precursory signals appear synchronously. The duration of acoustic emission, microseismic and charge induction precursory signals is increasing in the instability destruction stage. When the angle of the fault zone reaches 30°, the mutability of acoustic emission, microseismic and charge induction signal increases, the time to enter the dangerous stage is much earlier, and the acoustic emission events of large magnitude increase significantly, and the large angle faults of coal mine are more dangerous. The intensive and high amplitude synchronous precursory signals of acoustic emission, microseism and charge induction are produced before the instability destruction, and the signals duration is shorter. The intensive and strongest synchronous precursory signals of acoustic emission, microseism and charge induction are produced in the instability destruction, and the signals duration is longer. Acoustic emission monitoring data can better reflect the micro rupture of rock. And combined with the acoustic emission, microseismic and charge induction precursory signals, the precursory information of rock instability destruction can be obtained more accurately. 相似文献
997.
从经济增长、资源承载利用、减排环保、科技创新和社会保障5个方面构建了区域绿色发展评价指标体系。通过熵权法确定各指标权重,结合TOPSIS方法测算了云南省2011~2015年各区域绿色发展指数。研究结果表明:进出口总额占GDP比重、万人专利申请数、万人专利授权数,万人独立研究和开发机构人员数和万人普通高校在校学生人数5个指标所占权重较大,是影响区域绿色发展的重要因素。昆明市绿色发展水平一直居首位,西双版纳州、德宏州、迪庆州、玉溪市、怒江州的绿色发展水平居前列。红河州、临沧市、文山州、普洱市和保山市相对绿色发展水平较低。云南省各地区绿色发展水平普遍较低,且空间差异明显;区域绿色发展水平仍有很大的提升空间。 相似文献
998.
999.
1000.
中国能源行业碳排放强度下降过程中的省际减排成效评价 总被引:2,自引:2,他引:0
采用矫正系数衡量各省份的减排有效性,根据各省份能源行业碳排放强度及产值份额构建自上而下的全国能源行业碳排强度恒等式,运用LMDI-Ⅰ分解方法获取各省份、各省份能源行业碳排放强度及产值份额对全国能源行业碳排放强度下降的贡献率,并遵循“减排有效性-碳排放强度贡献-省份综合贡献-减排有效性与省份综合贡献关系”的思路对中国能源行业碳排放强度下降过程中各省份的减排成效进行评价。结果显示:① 中国能源行业碳排放强度呈逐年下降趋势,2016年能源行业碳排放强度较2005年下降45%。② 超过一半的省份为减排有效区且数量呈增加趋势,而减排未达标的省份多数为经济欠发达地区,各省份间的减排路径存在显著差异。③ 多数省份能源行业碳排放强度的贡献率呈上升趋势,省份差异逐渐缩小。④ 省份减排综合贡献的进位赶超势头强劲,绝大多数省份对全国能源行业碳排放强度的下降作出了贡献,且多个省份的综合贡献等级呈正向发展,东部地区是主要的降排贡献区。⑤ 减排成效良好省份数量最多,中等区多散布于东部沿海地区及少数内陆地区,欠佳区在西部地区空间格局保持相对稳定。未来各省份不仅要根据自身的减排成效特征因地制宜的选择低碳发展道路,还应与全国碳排放强度的下降形成良性互动。 相似文献