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991.
A new moored microstructure recorder (MMR) is designed, developed, tested, and evaluated. The MMR directly measures the high-frequency shear of velocity fluctuations, with which we can estimate the dissipation rate of turbulent kinetic energy. We summarize and discuss methods for estimating the turbulent kinetic energy dissipation rate. Instrument body vibrations contaminate the shear signal in an ocean field experiment, and a compensating correction successfully removes this contamination. In both tank test and ocean field experiment, the dissipation rate measured with the MMR agreed well with that measured using other instruments. 相似文献
992.
The relationship between economic development and energy consumption is revealed by employing cointegration theory, the index decomposition method, and a log-linear regression approach based on a case study of Jilin Province, China. The results suggest: 1) the economic development and energy consumption are interdetermined, whose relationship is positive and long-term. The economic development is highly depending on the energy in Jilin Province. 2) Under the condition of other unchanged factors, the change of industrial energy efficiency contributes to the energy saving, while that of industrial structure increases the energy consumption. 3) The industrial structure change enhances the energy intensity, but the energy utility efficiency change lowers it. From the view of contribution to the energy consumption, the contribution of industrial structure was more than that of the energy utility efficiency in 2000-2011. 4) In 2000-2011, the comprehensive energy intensity change and hydroelectricity energy intensity change were related to all industrial structures' change, and the influencing factors about structure of oil energy intensity change were more than those of coal energy intensity change; from the impact degree, agricultural proportion decreased exerted an positive and greater effect on lowering the energy intensity of comprehensive energy and hydroelectricity, and industrial one did on coal and natural gas. Some conclusions can be drawn as follows: the major way to promote the coordinated development of the industrial economy and energy consumption is to optimize the industrial structure by increasing the proportion of the tertiary industry and low energy consumption industrial sectors and to enhance the energy utility efficiency. 相似文献
993.
“Energy” presents a number of complex and interrelated challenges regarding the environment, economy, and politics. In this paper, we argue that cartography should help clarify our understanding of energy issues, but ask whether this has in fact been the case. In a review of over 100 articles pulled from twenty‐three peer‐reviewed geography journals, we qualitatively assess energy maps published since the early 20th century, examining trends in topic and cartographic technique. Energy maps in geography journals have focused on North America and Western Europe while relying on proportional symbols, grayscale production, and the analysis of energy phenomena at the national scale—tendencies that in many instances have limited our understanding of the ways in which energy is actually consumed. Simultaneously, cartographers are limited to the energy data available to them, frequently precluding small‐scale consumption analysis or consideration of diurnal and seasonal trends. We argue that the future of energy cartography relies on access to consumption data coupled with greater user interactivity. 相似文献
994.
995.
设计了一种近岸波浪动能发电设备,其特有的双通道结构可将海水的双向流动转化为叶轮的单向旋转。同时,根据近岸波浪能的特点,分析了近岸海水动能和远离海岸波浪波高的关系,研究了通过发电设备的水流速度和设备的流通面积。 相似文献
996.
东北地区风能资源空间分布特征与模拟 总被引:2,自引:1,他引:1
利用东北地区104个气象站1991~2010年观测资料和70个测风塔2009年6月~2010年5月测风资料,进行了风能资源空间分布特征分析,并利用中尺度模式WRF进行风能资源空间模拟,以研究观测站点稀少地区的风能资源分布特征。研究结果表明:1东北地区气象站和测风塔揭示的大风区域主要分布在平原和丘陵的高海拔地带。2中尺度模式WRF能够较好地模拟东北区域风速分布的气候特征,模拟结果既反映出平原大面积的大风区域,也可反映出山区因地形起伏造成的风速空间分布差异。3对风能资源参数模拟结果进行海拔高度订正,可以进一步提高模式计算结果的准确性和可靠性。4松嫩平原、辽河平原、三江平原70 m高度年平均风功率密度在300~500 W/m2之间,属于风能资源可利用区或较丰富区;在辽宁省西部、吉林省中部和黑龙江省中部丘陵以及东北地区东南部的呈东北-西南走向的中高山区的70 m年平均风功率密度可达300 W/m2以上,局部地方可达500 W/m2以上,风能资源丰富。 相似文献
997.
Impact of Anthropogenic Heat Release on Regional Climate in Three Vast Urban Agglomerations in China简 总被引:5,自引:0,他引:5
We simulated the impact of anthropogenic heat release (AHR) on the regional climate in three vast city agglomerations in China using the Weather Research and Forecasting model with nested high-resolution modeling.Based on energy consumption and high-quality land use data,we designed two scenarios to represent no-AHR and current-AHR conditions.By comparing the results of the two numerical experiments,changes of surface air temperature and precipitation due to AHR were quantified and analyzed.We concluded that AHR increases the temperature in these urbanized areas by about 0.5℃-1℃,and this increase is more pronounced in winter than in other seasons.The inclusion of AHR enhances the convergence of water vapor over urbanized areas.Together with the warming of the lower troposphere and the enhancement of ascending motions caused by AHR,the average convective available potential energy in urbanized areas is increased.Rainfall amounts in summer over urbanized areas are likely to increase and regional precipitation patterns to be altered to some extent. 相似文献
998.
Unlike previous studies on wind turbulence spectrum in the planetary boundary layer, this investigation focuses on high-altitude (1-5 km) wind energy spectrum and turbulence spectrum under various weather conditions. A fast Fourier transform (FFT) is used to calculate the wind energy and turbulence spectrum density at high altitudes (1-5 km) based on wind profiling radar (WPR) measurements. The turbulence spectrum under stable weather conditions at high altitudes is expressed in powers within a frequency range of 2 × 10-5-10-3 s-1, and the slope b is between -0.82 and -1.04, indicating that the turbulence is in the transition from the energetic area to the inertial sub-range. The features of strong weather are reflected less obviously in the wind energy spectrum than in the turbulence spectrum, with peaks showing up at different heights in the latter spectrum. Cold windy weather appears over a period of 1.5 days in the turbulence spectrum. Wide-range rainstorms exhibit two or three peaks in the spectrum over a period of 15-20 h, while in severe convective weather conditions, there are two peaks at 13 and 9 h. The results indicate that spectrum analysis of wind profiling radar measurements can be used as a supplemental and helpful method for weather analysis. 相似文献
999.
This article attempts to disentangle the determinants of the adoption of renewable energy support policies in developing and emerging countries. By analyzing policies already implemented in industrialized countries, we focus on the diffusion but not the invention of climate-relevant policies. We look at four different types of policies (renewable energy targets, feed-in tariffs, other financial incentives and framework policies) and consider both domestic factors and international diffusion mechanisms utilizing a discrete-time events history model with a logit link on a self-compiled dataset of grid-based electricity policy adoption in 112 developing and emerging countries from 1998 to 2009. In general, we find stronger support for the domestic determinants of policy adoption, but also substantial influence of international factors. Countries with a larger population and more wealth have a higher probability of adopting renewable energy policies. Only in some specific cases do natural endowments for producing renewable energy encourage governments to adopt policies, and hydro power resources even correlate negatively with the adoption of targets. Among the international determinants, emulation from colonial peers and membership within the EU seem to facilitate policy adoption. International climate finance is less relevant, as the Global Environmental Facility and the Clean Development Mechanism may only increase the adoption of frameworks and targets, but they have no influence on tariffs and incentives. 相似文献
1000.
Critical to the environmental success of sustainable innovations is the adoption by consumers. The consensus is that instrumental shortcomings of sustainable innovations inhibit their adoption. However, we argue that the adoption of sustainable innovations does not exclusively depend on their instrumental attributes. In addition, people may be motivated to adopt sustainable innovations because of their positive environmental and symbolic attributes, that is, they benefit the environment and can be used to signal positive characteristics to oneself and others. We studied the significance of instrumental, environmental and symbolic attributes for the adoption of two sustainable innovations: electric cars (Study 1) and local renewable energy systems (Study 2), following two methods. Results showed that when asked directly, participants claimed that instrumental and environmental attributes are most important for their decision to adopt sustainable innovations, while symbolic attributes were rated as less important. Interestingly, evaluations of the symbolic and environmental attributes of sustainable innovations, but not evaluations of their instrumental attributes, predicted different indicators of adoption (i.e., interest in, the acceptability of, and intention to adopt these sustainable innovations), suggesting that the significance of symbolic motives for adopting sustainable innovations may not be recognized by consumers. Moreover, favorable evaluations of symbolic attributes particularly enhanced interest in and acceptability of sustainable innovation when participants evaluated the instrumental attributes more negatively, but not when instrumental attributes were evaluated relatively positively. This suggests that the instrumental drawbacks of sustainable innovations may sometimes strengthen their positive signal, which can promote interest in sustainable innovations. 相似文献