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41.
王蕾 《科技和产业》2019,19(8):49-53
梳理国内外动力和储能电池产业发展情况,从产业规模、重点企业、产业链、培养方向等角度剖析了泰州市动力和储能电池产业的现状问题,并针对性地提出了发展建议。  相似文献   
42.
Luby变换(Luby Transform,LT)码作为信道编码应用于电力线通信(Power Line Communication,PLC),可实现电信号的可靠传输。度分布对LT码编译码性能的影响至关重要。为了得到更优的度分布,首先调整二进制指数分布(Binary Exponential Distribution,BED)中的度数比例,获得一种译码性能更优的改进的二进制指数分布(Improved BED,IBED)。然后,根据IBED在冗余度较小时译码成功率高,而冗余度增大后鲁棒孤子分布(Robust Soliton Distribution,RSD)的译码性能表现更佳的特点,通过求和归一化的方式将IBED与RSD两种度分布的优势进行有机结合,提出一种新型二进制鲁棒孤子分布(Binary RSD,BRSD)。仿真结果表明,与其他方法及传统的RSD相比,采用新度分布进行LT编码,可明显降低译码开销,并节约编译码耗时。将新型度分布应用于基于LT码的PLC系统中,能有效地抑制PLC信道中各种噪声对电信号的干扰,并提高通信效率。  相似文献   
43.
While the literature on business power and global finance has illuminated the ways in which financial institutions limit the policy autonomy of states in developing countries, we know much less about the circumstances under which the power of financiers is undermined. In this article, I advance explanations of these circumstances by arguing that state access to natural resource revenues reduces the power of financial institutions and enhances the capacity of the state to pursue central bank policies which violate the interests of major financiers. I employ a case study of central bank policy in Nigeria to probe this argument and find evidence that supports the claim that whenever the Nigerian government's access to resource revenues increased, the state's capacity to diverge from financiers’ preferred central bank policies and to advance its own preferences increased as well. The analysis provides the basis for broader propositions about the policy space of developing countries vis-à-vis financial institutions and the variability of structural power.  相似文献   
44.
周琼芳  张全斌 《科技和产业》2019,19(10):125-129
海上风电是最具规模化开发价值的可再生能源,预计2020年我国累计装机容量突破8.5GW。海上风电的运维成本在度电成本占比25%~40%。2019年起国家推行风电平价上网,对海上风电的发展带来深刻影响。通过海上风电度电成本分析,建立成本-效益模型。研究发现,风电设备的可靠性、可利用率决定了运维成本和度电成本的水平。基于成本-效益模型测算某海上风电项目的度电成本,风机设备可利用率为97.15%时,运维成本下降26.88%,度电成本最低,为0.575 2元/kW·h。  相似文献   
45.
Firms in emerging economies are faced with multiple, incompatible institutional forces in their environmental activities. Which of these forces will be dominant and instantiated within an organization is partly determined by the social relationships that a firm maintains with external actors. This paper investigates the relationship between board social ties and the level of environmental responsibility undertaken by firms in China, an emerging economy, by categorizing board social ties into three types in terms of the three isomorphic forces in the institutional field (coercive, normative and mimetic). Drawing on institutional and agency theories, using a sample of listed firms in environmentally sensitive industries, and a generalized least squares regression method, the results provide empirical evidence that ties that are linked to coercive and normative forces (i.e., political organizations and universities) are related to a higher level of environmental responsibility; however, those that are linked to mimetic forces (i.e., industrial peers) have a negative association with environmental responsibility, which is mitigated by CEO power. These findings suggest that the heterogeneous effects of board social ties on environmental responsibilities experienced by firms in a context of environmentalism are at an early stage.  相似文献   
46.
This paper examines consumption risk sharing among 16 regions in South Korea over the 2000–2016 period. The empirical results show that 91.8 percent of shocks to gross regional domestic product are smoothed in South Korea. Capital markets, the tax‐transfer system and credit markets absorb 29.9, 28.9 and 33.0 percent of shocks to gross regional domestic product, respectively. Most notably, South Korea relies more on credit markets for risk sharing than capital markets, an opposite pattern to advanced countries like the USA, Canada and Australia. Furthermore, the patterns of consumption risk sharing are different before and after the 2007–2008 global financial crisis, and differences in regional industrial structure and local development can influence these patterns. This paper attempts to infer the connection between these findings and both the rapid economic growth of South Korea and the Asian and global financial crises.  相似文献   
47.
This research examines the effect of desire for exclusivity on evaluations of luxury experiences and proposes a boundary condition for the effect. The scarcity effect literature suggests that consumers prefer scarce products due to limited supply because they appeal to consumers’ desire for exclusive consumption. Building on this thesis, the current research argues that luxury experiences are intrinsically scarce enough to appeal to consumers’ desire for exclusivity: Consumers with a strong desire for exclusivity will evaluate luxury experiences more favorably than those with a weak desire for exclusivity. A pilot study confirms a positive correlation between consumers’ desire for exclusivity and attitudes toward luxury experiences. Study 1 demonstrates that consumers with a strong desire for exclusivity show more favorable attitudes toward luxury experiences than those with a weak desire for exclusivity. Further, Study 2 finds that consumers’ power state (powerful vs. powerless) moderates the effect of desire for exclusivity on their affinity for luxury experiences: Only when feeling powerful do consumers with a strong desire for exclusivity evaluate luxury experience more favorably than those with a weak desire for exclusivity. However, this is not the case when consumers feel powerless.  相似文献   
48.
We use a modified version of the stochastic frontier model to estimate oligopoly markups above the perfectly competitive frontier, separating out deterministic markups from purely stochastic markups. Using data from 42 US food processing industries between 1990 and 2010, empirical results indicate a widespread incidence of oligopoly power, with Lerner indexes averaging approximately 21%. Further, the estimated markups increase with industrial concentration but decrease with price elasticities and imports. Finally, the estimated Lerner indexes are in the range of previous food industry estimates using New Empirical Industrial Organization (NEIO) models.  相似文献   
49.
《The World Economy》2018,41(3):674-698
We examine the interest rate sensitivity of both deposits and credits at Islamic and conventional banks in Turkey. We find that the bank lending channel is especially operative for Islamic banks. Impulse responses for conventional and Islamic banks reveal that Islamic bank depositors’ sensitivity to policy rate changes is substantially larger than that of conventional bank depositors. Next to heavily dependence on deposit funding, we consider that inertia in Islamic bank deposit rates impedes these banks to keep those depositors who consider the opportunity cost of monetary policy rates is unbearable. On the lending side, we obtain similar results, implying that tight monetary policy leads to a larger contraction in Islamic bank credits. This finding is a reflection of the favourable attitude of Islamic banks towards small and medium‐sized enterprise (SME) financing. When similar relationships are analysed for currency and inflation shocks, we again find larger responses for Islamic banks showing the cyclical nature of SME credits.  相似文献   
50.
多径效应导致基于信号接收强度(RSSI)的室内定位方法精度不高,采用更细粒度的物理层信道状态信息(CSI)可以区分不同路径,提高定位精度。在已有基于CSI室内定位方法的基础上,通过改进对数距离路径损耗模型,得到CSI与传输距离的关系,并结合目标位置所测得的CSI值回归出目标与发射端的距离,最后通过三边定位法预测出目标的位置坐标。实验表明,相比基于RSSI的定位方法以及已有的基于CSI的定位方法,所提方法2 m以内的误差概率提高了将近40%和20%,有效提高了定位精度。  相似文献   
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