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61.
Preface     
Different from traditional tax audit, supervision with self-audit is a combination of audit by the taxpayer himself and audit by the tax authority. This paper mainly studies a taxpayer’s optimal policy of tax evasion under supervision with self-audit and its related properties, in order to deduce some effective suggestions and theoretical bases to restrain tax evasion. Assuming that only a certain proportion of evaded tax can be discovered when the audit is executed, the authors first formulate a static model with self-audit. This model is divided into two stages. At the first stage, taxpayers declare their taxes, then the tax authority chooses audit objects, based on a known probability, and announces the result; if the taxpayer is chosen, he will enter the second stage, during which he has a chance to pay the evaded tax and the corresponding late fees and then is audited by the tax authority. The authors show the existence and uniqueness of the optimal amount of tax evasion at the first stage and the optimal proportion to self-expose at the second stage. The authors also discuss the related properties of the interior solution, and do elasticity analyses on some parameters. Besides, the authors extend the static model into the corresponding two-period model, and study the existence and uniqueness of the solution of the extended model. Finally, under the assumption that tax evasion can only be discovered with a certain probability when the audit is executed, the authors formulate another static model with self-audit and investigate its properties. This research is partially supported by the National Natural Science Foundation of China under Grant Nos. 60674082, 70221001, and 70731003.  相似文献   
62.
Different from traditional tax audit, supervision with self-audit is a combination of audit by the taxpayer himself and audit by the tax authority. This paper mainly studies a taxpayer's optimal policy of tax evasion under supervision with self-audit and its related properties, in order to deduce some effective suggestions and theoretical bases to restrain tax evasion. Assuming that only a certain proportion of evaded tax can be discovered when the audit is executed, the authors first formulate a static model with self-audit. This model is divided into two stages. At the first stage, taxpayers declare their taxes, then the tax authority chooses audit objects, based on a known probability, and announces the result; if the taxpayer is chosen, he will enter the second stage, during which he has a chance to pay the evaded tax and the corresponding late fees and then is audited by the tax authority. The authors show the existence and uniqueness of the optimal amount of tax evasion at the first stage and the optimal proportion to self-expose at the second stage. The authors also discuss the related properties of the interior solution, and do elasticity analyses on some parameters. Besides, the authors extend the static model into the corresponding two-period model, and study the existence and uniqueness of the solution of the extended model. Finally, under the assumption that tax evasion can only be discovered with a certain probability when the audit is executed, the authors formulate another static model with self-audit and investigate its properties.  相似文献   
63.
仿青蛙跳跃机器人运动学研究   总被引:1,自引:0,他引:1  
提出了仿青蛙跳跃机器人机构模型及运动学研究的方法。基于对青蛙运动的研究,提出了仿青蛙机器人单侧跳跃机构的分析模型,采用D-H法,建立了机器人起跳与腾空两个阶段,其前肢和后肢的运动学方程,进行了正、逆运动学研究。分析机器人四肢的运动空间,并通过实例计算,验证了研究结果和生物学实测结果相一致,从而证明了这一仿生跳跃机构模型的可行性和仿生机构运动研究方法的有效性。得出的结论将为仿青蛙跳跃机器人的设计及控制提供理论基础。  相似文献   
64.
1 IntroductionTheJobShopSchedulingProblemisawell-knownNP-hardproblem,whichattractslotsofmathematiciansallovertheworldspendingmuchtimeandenergyinthisfield.Uptonowtherearemanyefficientheuristicalgorithms,whichhadalreadybeendeveloped,buttheinfeasiblesolutioncertainlypossessesthemajorityofsearchspacewhichhasinfluencedtheefficiencyofthesealgorithms.Atthemoment,noonehasbeenfoundtobededicatingtothequantitativeanalysisoftheinfeasiblesolutionproblem.InthispaperthestructureofinfeasiblesolutiontoJSS…  相似文献   
65.
考虑具有单重延误休假的MxG(MG)1可修排队系统,其中休假时间、服务时间、修理时间和延误休假时间都为任意分布(不一定是连续型),采用一种较简洁的方法,我们获得队长的瞬态解、平稳解和队长的随机分解表达式,同时给出了一些特殊情形下队长的随机分解结果  相似文献   
66.
Spurious signals in direct digital frequency synthesizers (DDFSs) are partly caused by amplitude quantization and phase truncation, which affect their application to many wireless telecommunication systems. Thee signals are deterministic and periodic in the time domain, so they appear as line spectra in the frequency domain. Two types of spurious signals due to amplitude quantization are exactly formulated and compared in thetime and frequency domains respectively. Then the frequency spectra and power levels of the spurious signals due to amplitude quantization in the absence of phase-accumulator truncation are emphatically analyzed, and the effects of the DDFS parameter variations on the spurious signals are thoroughly studied by computer simulation. And several important conclusions are derived which can provide theoretical support for parameter choice and spurious performance evaluation in the application of DDFSs.  相似文献   
67.
递推加权最小二乘算法的研究   总被引:1,自引:0,他引:1  
通常在使用递推加权最小二乘算法时,需要设计矩阵列满秩.从极限理论的角度出发,对设计矩阵列不满秩时加权最小二乘估计的递推算法进行了理论证明和分析,得出了在任意第n步,未知参数估计值收敛于由前n组数据所决定的极小范数加权最小二来解,并且此解是唯一的,仿真结果同样验证了该结论的正确性.  相似文献   
68.
利用分布估计算法(EDA)的全局搜索性能及差分进化(DE)算法的局部优化能力,提出了一种多目标优化问题的混合智能求解方法DE-EDA.DE-EDA的子代个体由两部分构成,一部分按差分进化算法生成,另一部分则是通过对分布估计算法的概率模型进行随机采样生成.利用模拟退火技术在线调整尺度因子Pr,即在进化的初期选择较大的Pr,以保证EDA起主导作用,由EDA引导DE搜索向Pareto前端,增加全局搜索能力,然后在进化的过程中逐渐降低Pr,使得DE逐渐占据主导作用,确保解精确收敛到Pareto前端.通过4组基准函数来测试算法性能,并与NSGA-Ⅱ和DE算法进行实验比较,结果表明该方法不仅解的多样性和分布性好,而且能够有效提高种群进化的收敛速度,是一种求解多目标优化问题的有效方法.  相似文献   
69.
传统直接转矩控制转矩、磁链和电流脉动较大,速度传感器的安装容易使系统可靠性降低、成本增加.为解决以上问题,采用扩展卡尔曼滤波器对定子磁链进行观测,并对转速进行估计,实现表面式永磁同步电机无速度传感器直接转矩控制,克服传统直接转矩控制中积分器的缺陷,保持直接转矩控制固有的转矩响应快和系统鲁棒生强的优点,能够对电机参数变化、负载扰动具有较强的鲁棒性,有效地改善了系统的动、静态运行生能,仿真和实验验证了该方法的可行性和有效性.  相似文献   
70.
巫庆辉  邵诚 《系统仿真学报》2007,19(1):89-92,215
定子磁场定向的直接转矩控制逐渐被广泛应用于高性能异步电机调速系统。定子磁链估计精度是影响控制系统动态、稳态性能的主要因素。由于定子电阻参数变化及低通滤波器的影响,尤其低速运行时,传统定子磁链估计方法的估计精度及快速性往往很差。提出了一个全新的改进U-I模型定子磁链估计方案,不仅解决了定子电阻整定补偿问题。而且解决了低通滤波器截止频率优化补偿问题.在此基础上,建立直接转矩控制方案的仿真系统,仿真结果表明提出的方案能够使异步电机在低速到高速范围内都能得到令人满意的性能。  相似文献   
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