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61.
This paper contributes an empirical test of key themes of the literature on natural resource conflict. Survey and interview data from an ongoing project in Azerbaijan provide insights into an unexpected lack of conflict in Azerbaijan related to the environment, resources and energy despite the predictions of resource conflict literature. We contend that questions about public perceptions about the environment and other daily concerns are critical if we are to understand who is likely (or unlikely) to be involved in conflict and why. The data presented in this paper demonstrate that Azerbaijani citizens rank environmental and resource issues among their immediate concerns and their top concerns for the country. However, compared to other day-to-day concerns such as the Nagorno-Karabakh conflict and economic concerns, environment-related concerns do not appear to be sufficient to motivate widespread violent conflict or citizen dissent related to environmental or natural resource conditions. 相似文献
62.
Scott W. White 《Natural Resources Research》2006,15(4):271-281
This paper updates a life-cycle net energy analysis and carbon dioxide emissions analysis of three Midwestern utility-scale
wind systems. Both the Energy Payback Ratio (EPR) and CO2 analysis results provide useful data for policy discussions regarding an efficient and low-carbon energy mix. The EPR is
the amount of electrical energy produced for the lifetime of the power plant divided by the total amount of energy required
to procure and transport the materials, build, operate, and decommission the power plants. The CO2 analysis for each power plant was calculated from the life-cycle energy input data.
A previous study also analyzed coal and nuclear fission power plants. At the time of that study, two of the three wind systems
had less than a full year of generation data to project the life-cycle energy production. This study updates the analysis
of three wind systems with an additional four to eight years of operating data.
The EPR for the utility-scale wind systems ranges from a low of 11 for a two-turbine system in Wisconsin to 28 for a 143-turbine
system in southwestern Minnesota. The EPR is 11 for coal, 25 for fission with gas centrifuge enriched uranium and 7 for gaseous
diffusion enriched uranium. The normalized CO2 emissions, in tonnes of CO2 per GWeh, ranges from 14 to 33 for the wind systems, 974 for coal, and 10 and 34 for nuclear fission using gas centrifuge and gaseous
diffusion enriched uranium, respectively. 相似文献
63.
山西沁水盆地煤层气成藏的微观动力能条件研究 总被引:2,自引:4,他引:2
煤层气成藏的微观动力能条件主要包括煤储层的孔隙—裂隙系统、煤储层的生气作用和储气作用两个方面。以山西沁水盆地为例,深入剖析了煤储层的孔隙—裂隙系统及其发育历程、煤储层的生气作用与能量聚散,阐明了煤层气成藏的微观动力能对成藏效应的控制作用。结果表明:构造作用对储层渗透率具有明显的控制作用,成烃增压致使能量聚集,成为盖层突破作用的主要驱动力,而能量放散则主要是通过煤储层孔隙—裂隙系统的产生、发展。根据上述研究成果,沁水盆地煤层气成藏的地质区划结果为:盆地南部的有利区带为阳城和晋城的北部地区,包括潘庄、樊庄、郑庄等地区;盆地中部的有利区带为安泽—沁源地区,位于盆地西斜坡的中南部;盆地北部的可能有利区带为寿阳东南部地区,位于榆次东北部和阳泉西南部之间。 相似文献
64.
注水煤体应力能 V-f 转化与释放机理研究 总被引:5,自引:0,他引:5
文章分析了在煤层注水湿润后煤体弹性能的转化与消耗过程,给出在湿润状态下能量由体变弹性能向形变弹性能转化进而自耗释放的理论模型。指出在坚硬干燥煤体中,注水后在水压力和毛细力的切割作用下,裂隙大量扩展,丰富了自由裂隙,产生更多的裂隙启发(裂隙切口),使原来近似的刚性煤体变成由裂隙分割的块体组成的组合体或半组合体。裂隙中水的粘滞作用及水分子吸附力使块体问粘性结合、刚度降低、形变增大。煤体形变弹性能自身消耗释放的形式有3种:产生剪应力导致自由裂隙问错动摩擦;强度降低,使裂隙启发被劈裂成自由裂隙;湿润煤体蠕变性增强,产生整体性移动作功。初步给出能量消耗的量化表达式。通过这一理论,能建立煤层注水湿润度与冲击地压灾害发生的更直接的关系,使进一步量化该关系成为可能。从更深层次解释煤层注水防治冲击地压的机理。 相似文献
65.
66.
67.
土壤热异常对地表能量平衡影响初探 总被引:3,自引:1,他引:3
将来自土壤深部的热通量引入off line的陆面过程模式 (NCAR—LSM ) ,通过长达 2a的数值试验对比分析了它对各层次土壤温度和地表能量平衡的影响。 在土壤底部引入 5W /m2 的热通量使底层土壤显著升温 ,但升温随着接近表层而迅速衰减。积分 3个月后 ,由地下进入地表的热流量增幅可达 1W/m2 以上 ,并持续增大到 5W /m2 ,地表最大升温约 0 .5K ,同时地表感热、蒸发潜热及长波辐射通量均有 1W /m2 左右的正异常 ;若将土壤热传导系数放大一个量级以加速热量交换 ,则地表升温提高到 1K以上 ,长波辐射增加 3W /m2 以上 ,超过了气溶胶全球平均的辐射效应。结果表明 :一定量值的土壤热异常对地表能量平衡和短期气候变化 (10 -1~ 10 1a)有着不可忽略的影响。同时 ,深入的资料分析、完善的陆面过程模式以及它与大气模式的耦合试验也是亟待进行的相关工作。 相似文献
68.
土壤热异常影响地表能量平衡的个例分析和数值模拟 总被引:6,自引:0,他引:6
The statistical relationship between soil thermal anomaly and short-term climate change is presented based on a typical case study. Furthermore, possible physical mechanisms behind the relationship are revealed through using an off-line land surface model with a reasonable soil thermal forcing at the bottom of the soil layer.In the first experiment, the given heat flux is 5 W m-2 at the bottom of the soil layer (in depth of 6.3 m)for 3 months, while only a positive ground temperature anomaly of 0.06℃ can be found compared to the control run. The anomaly, however, could reach 0.65℃ if the soil thermal conductivity was one order of magnitude larger. It could be even as large as 0.81℃ assuming the heat flux at bottom is 10 W m-2. Meanwhile, an increase of about 10 W m-2 was detected both for heat flux in soil and sensible heat on land surface, which is not neglectable to the short-term climate change. The results show that considerable response in land surface energy budget could be expected when the soil thermal forcing reaches a certain spatial-tem poral scale. Therefore, land surface models should not ignore the upward heat flux from the bottom of the soil layer. Moreover, integration for a longer period of time and coupled land-atmosphere model are also necessary for the better understanding of this issue. 相似文献
69.
Passive energy dissipation devices (EDDs), such as viscous dampers, viscoelastic dampers, etc., have been used to effectively reduce the dynamic response of civil infrastructures, such as buildings and bridges, subject to earthquakes and strong winds. The design of these passive energy dissipation devices (EDDs) involves the determination of the optimal locations and the corresponding capacities. In this paper, we present two optimal design methodologies for passive EDDs based on active control theories, including H∞ and H2 performances, respectively. The optimal design methodologies presented are capable of determining the optimal locations and the corresponding capacities of EDDs. Emphasis is placed on the application of linear matrix inequality (LMI) for the effective design of passive EDDs using the popular MATLAB toolboxes. One important advantage of the proposed approaches is that the computation of the structural response is not needed in the design process. The proposed optimal design methodologies have been applied to: (i) a 10‐storey building and a 24‐storey building both subject to earthquake excitations, and (ii) a 76‐storey wind‐excited benchmark building, to demonstrate the advantages of the proposed design methodologies over the conventional equal capacity design. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
70.
Dynamic damaging potential of ground motions must be evaluated by the response behaviour of structures, and it is necessary to indicate what properties of ground motions are most appropriate for evaluation. For that purpose, the behaviour of energy input process and hysteretic energy dissipation are investigated in this study. It is found that the momentary input energy that is an index for the intensity of input energy is related to the characteristics of earthquakes such as cyclic or impulsive, and to the response displacement of structures immediately. On the basis of these results, a procedure is proposed to predict inelastic response displacement of structures by corresponding earthquake input energy to structural dissipated damping and hysteretic energy. In this procedure the earthquake response of structures is recognized as an input and dissipation process of energy, and therefore structural properties and damaging properties of ground motions can be taken into account more generally. Lastly, the studies of the pseudodynamic loading test of reinforced concrete structure specimens subjected to ground motions with different time duration are shown. The purpose of this test is to estimate the damaging properties of ground motions and the accuracy of the proposed prediction procedure. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献