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51.
5"E"因素会通过各种渠道对政治思想工作产生影响,可以通过畅通渠道,加强宣传、强化监督等手段引导其对新闻中心政治思想工作发挥积极作用。 相似文献
52.
通过对长株潭"3+5"城市群产业结构现状与同等收入水平的国际"标准"产业目标,发现长株潭"3+5"城市群的产业结构现状与国际"标准"产业目标结构差距较大,国际"标准"产业目标结构不宜作为其产业调整的近期目标结构.最后,结合长株潭"3+5"城市群内各市的发展现状,制定了各市产业调整的近期目标结构. 相似文献
53.
The multiple effects of carbon values on optimal rotation 总被引:2,自引:0,他引:2
Non-consumptive benefits which increase with crop age, like keeping carbon sequestered, lengthen optimal rotation compared with rotation for timber alone. High proposed carbon prices may extend rotation indefinitely. Carbon storage in wood products reduces this tendency. Biomass as an energy source displacing fossil fuels favours rotations near those of maximum biomass productivity. Use of sawn timber to displace structural materials with high embodied carbon favours somewhat longer rotations. Effects of rotation on soil carbon, and fossil carbon volatilised in harvesting operations, are further complications. Including all carbon effects results in optimal rotations somewhat longer than those based only on timber value, but shorter than those based on timber plus forest carbon. To include all factors intuitively is not possible: balanced appraisal needs economic calculations. 相似文献
54.
Accounting for Negative,Zero and Positive Willingness to Pay for Landscape Change in a National Park
Nick Hanley Sergio Colombo Bengt Kriström Fiona Watson 《Journal of Agricultural Economics》2009,60(1):1-16
In contingent valuation, despite the fact that many externalities manifest themselves as costs to some and benefits to others, most studies restrict willingness to pay to being non‐negative. In this paper, we investigate the impact of allowing for negative, zero and positive preferences for prospective changes in woodland cover in two UK national parks, the Lake District and the Trossachs. An extended spike model is used to accomplish this. The policy implications of not allowing for negative values in terms of aggregate benefits are also investigated, by comparing the extended spike model with a simple spike making use of only zero and positive bids, and a model which considers positive bids only. We find that ignoring negative values over‐states the aggregate benefits of a woodland planting project by up to 44%. 相似文献
55.
56.
5G系统使用解调参考信号(Demodulation Reference Signal,DMRS)用于下行信道估计,工程中通常采用插值法得到数据位置信道响应,考虑实际信道中噪声的影响,频域采用线性最小均方误差(Linear Minimum Mean Squared Error,LMMSE)插值算法。针对LMMSE需要获取信道先验统计特性以及存在矩阵求逆运算量大问题,利用信号时域内能量集中特点估计出信道均方根时延、信噪比和信道自相关矩阵,对于DMRS信号在频域上间隔较大、DMRS信号所在子载波相关性不强的问题,通过引入导频加密方法提升DMRS信号所在子载波间的相关性以提升信道估计性能,并通过滑动窗口插值方法进一步降低LMMSE算法求逆运算复杂度。仿真结果表明,所提算法均方误差和误码率总体均优于线性插值和基于矩阵奇异值分解的LMMSE算法,并与传统LMMSE算法相比性能极为接近,而且复杂度降低了99.85〖WT《Times New Roman》〗%〖WTBZ〗,适合实际工程应用。 相似文献
57.
刘星 《中国高新技术企业评价》2010,(1):11-13
快速傅里叶变换(FFT)是离散傅里叶变换(DFT)的快速算法,而分裂基FFT算法是所有FFT算法中一种效率较高的一种算法,有着广泛的应用。在高速的系统要求下,文章选择分裂基FFT算法作为实现高速FFT处理器的基本算法。文中设计采用了并行处理、流水线技术等有效的实现方法,在Virtex-5 FPGA平台上有着很好的效果,并且满足了高速的系统要求。结果显示,系统延时只有13个周期,并且在资源利用上面有很高的效率。 相似文献
58.
随着西部经济的进一步发展,该区内部经济发展不平衡的问题也日渐凸显。文章在梳理西部省区经济差异发展状况和产业结构演变历程的基础上,运用基尼系数对西部12省区进行了产业分解。结果表明,二、三产业发展水平是西部经济差异化扩大的主要因素,而地理集中程度又是导致西部二、三产业发展水平差异化的主要因素。 相似文献
59.
Designing and evaluating sustainable development pathways for semi‐subsistence crop–livestock systems: lessons from Kenya 下载免费PDF全文
Achieving the Sustainable Development Goals (SDGs) in African agriculture requires a better understanding why high levels of poverty and resource degradation persist in African agriculture despite decades of policy interventions and development projects. In this article, we hypothesize that policies need to account for the key features of the semi‐subsistence crop–livestock systems (CLS) in the region to become effective. The semi‐subsistence CLS are characterized by a high degree of biophysical and economic heterogeneity and a complex, diversified production system involving a combination of subsistence and cash crops with livestock. We investigated the potential for interventions proposed by the Government of Kenya to meet the SDGs by 2030. The analysis uses an integrated modeling approach designed to deal with the key features of these systems. A strategy that stimulates rural development, increases farm size to a sustainable level, and reduces distortions and inefficiencies in input and output markets could lead to a sustainable development pathway and achieve the SDGs for rural households dependent on CLS. 相似文献
60.
Dutch glasshouse firms are facing the introduction of a system of tradable CO2 emission quotas. This paper employs a non‐parametric method for modelling tradable CO2 emissions of Dutch glasshouse firms. The method is capable of generating shifts in CO2 emissions across the sample of firms. Moreover, changes in volumes of outputs produced and inputs used are computed. Results show that firms using a conventional heating technology will be net purchasers of CO2 emissions, whereas firms using more advanced heating technologies will sell part of their emission quota. 相似文献