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排序方式: 共有2719条查询结果,搜索用时 15 毫秒
1.
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   
2.
This paper constructs a model with four groups of households who have preferences over labor supply, consumption of polluting (energy related) and non-polluting (non-energy) goods, and emissions. It quantifies the model for the French economy and computes its optimal tax equilibria under nine second-best tax regimes. We find that the redistributive role of environmental taxes requires the polluting goods to be taxed at a rate much below their marginal social damage. These goods may even require an outright subsidy if the society values equality ‘a lot’. Secondly, if environmental taxes that have an exclusively externality-correcting role, they benefit all types—although the gains are rather modest. The gains and losses become more substantial when environmental taxes have a redistributive role as well. Third, setting the environmental tax at its Pigouvian level, rather than its optimal externality-correcting-cum-redistributive level, benefits the high-income group at the expense of the low-income groups. Fourth, nonlinear taxation of polluting goods, and nonlinear commodity taxation in general, is a powerful redistributive mechanism. Fifth, introducing environmental taxes in the current French tax system, with its suboptimal income taxes, results in substantial welfare gains for the highest income group and a sizable loss for the least well-off persons.  相似文献   
3.
诗歌是情感的艺术,诗人把内隐的丰富多变的情感外化为磁性的诗化语言,使之传承、发展与升华。阐述了诗歌情感的层次特性及在语言、押韵、节奏、意境等方面的表现,力图唤起人们对诗歌情感内在层次的关注。  相似文献   
4.
馆长对图书馆的事业发展至关重要.探讨了图书馆馆长治理图书馆的非权力影响力,即指依靠馆长自身的素养,即德、才、仁、情等因素,使馆长更具向心力、凝聚力,从而推动图书馆工作的有效地运作,促进图书馆事业的蓬勃发展.  相似文献   
5.
The focus of this paper is twofold. First, it examines the impact on work effort of changes in government purchases financed with lump‐sum taxes, in a neoclassical framework, with respect to four industrialised countries. Second, it reconsiders the expenditure–work effort relationship in a broader conceptual context that allows for distortionary taxation and a disaggregation of the income and substitution effects. Our findings are shown to cast doubt on the empirical plausibility of the prevailing (neoclassical and New Keynesian) models which seem to rely heavily on the lump‐sum tax notion, thus ignoring the substitution effects of distortionary taxation.  相似文献   
6.
Stock Market Valuation of Deferred Tax Assets: Evidence from Internet Firms   总被引:1,自引:0,他引:1  
Abstract:   We use the provisions of SFAS No. 109 , Accounting for Income Taxes , to examine the extent to which stock prices of Internet firms were associated with expectations of future profitability before versus after the 'market correction' in early 2000. We find that the valuation of deferred tax assets of firms with business models reliant on the level of web site traffic was significantly greater after the market correction. In our view, this evidence is consistent with pre‐correction mispricing.  相似文献   
7.
Over the last decade, an increasing percentage of the profits reported by U.S. corporations were earned by their foreign subsidiaries and retained outside the United States resulting in the deferral of income taxes. The American Jobs Creation Act of 2004 provided a temporary federal tax incentive to remit such earnings, which resulted in the repatriation of $140 billion by the 30 firms comprising the Dow Jones Industrial Average. An analysis of the financial reporting disclosures made by these firms reveals that a tax expense was not fully recognized on a substantial portion of the earnings until repatriation because of an exception for foreign reinvestments deemed to be essentially permanent in duration. The implications of the currently acceptable accounting for undistributed foreign earnings are discussed as well as recommendations to improve the relevancy and reliability of the disclosures required for this exception to comprehensive recognition of deferred taxes.  相似文献   
8.
城镇污水的资源化处理已成为世界潮流,是人类实现可持续发展的重要途径之一。我国城镇污水处理BOT项目面临的法律缺陷主要包括法律位阶较低,条文内容相当简陋,存在许多立法空白,条文存在诸多法律障碍等,针对污水处理BOT项目的法律缺陷,应由国务院制定BOT行政法规,明确特许协议性质和政府的法律地位,构建完整的、系统的城镇污水处理BOT项目的法律制度。  相似文献   
9.
This paper is focused on the cost of raising capital in Germany. A cross-sectional analysis of flotation cost data for 117 IPOs over the years 1993–1998 is presented. We find average flotation costs to be 7.77 percent of gross proceeds, while underwriting fees average 5.01 percent. Our results extend the literature in two important directions. First, contrary to the conventional economies of scale view we find marginal spreads to be rather constant in gross proceeds and to be higher for more risky and more complex offerings. Fixed costs amount to 5 to 9 percent of underwriting fees. Second, by applying a principal component analysis we find issue size, an issuer risk factor, and an offering method complexity factor to have an economicaly meaningful impact on underwriting fees.  相似文献   
10.
This paper uses a general two-sector model of endogenous growth to examine how the spirit of capitalism affects the relation between public finance and growth. The spirit of capitalism is defined as acquisitive personal objectives. We find that if the spirit of capitalism is present, an increase in the share of government spending in output reduces the long-run growth rate. The negative relationship between fiscal spending and growth is consistent with empirical evidence.  相似文献   
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