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61.
公司诉讼风险的影响因素已得到学术界的广泛关注,但目前的研究较少从公司融资行为角度探讨,本文以2003-2015年中国A股上市公司为研究对象,探讨超额银行借款与公司诉讼风险之间的关系.实证研究发现,公司超额银行借款与诉讼风险存在显著正相关关系,公司内部控制水平的提高以及地区法律环境的改善可以显著弱化二者的正相关关系,并且公司内部控制与地区法律环境在弱化公司超额银行借款引起的诉讼风险过程中存在相互替代的关系.本文从公司超额银行借款行为出发,拓展了公司诉讼风险影响因素的研究视角;同时结合内部控制和地区法律环境,丰富了宏观环境对公司微观主体行为影响的研究.  相似文献   
62.
Traditional orthogonal strapdown inertial navigation sys-tem (SINS) cannot achieve satisfactory self-alignment accuracy in the stationary base: taking more than 5 minutes and al the iner-tial sensors biases cannot get ful observability except the up-axis accelerometer. However, the ful skewed redundant SINS (RSINS) can not only enhance the reliability of the system, but also improve the accuracy of the system, such as the initial alignment. Firstly, the observability of the system state includes attitude errors and al the inertial sensors biases are analyzed with the global perspective method: any three gyroscopes and three accelerometers can be assembled into an independent subordinate SINS (sub-SINS);the system state can be uniquely confirmed by the coupling connec-tions of al the sub-SINSs;the attitude errors and random constant biases of al the inertial sensors are observable. However, the ran-dom noises of the inertial sensors are not taken into account in the above analyzing process. Secondly, the ful-observable Kalman filter which can be applied to the actual RSINS containing random noises is established; the system state includes the position, ve-locity, attitude errors of al the sub-SINSs and the random constant biases of the redundant inertial sensors. At last, the initial self-alignment process of a typical four-redundancy ful skewed RSINS is simulated: the horizontal attitudes (pitch, rol ) errors and yaw error can be exactly evaluated within 80 s and 100 s respectively, while the random constant biases of gyroscopes and accelero-meters can be precisely evaluated within 120 s. For the ful skewed RSINS, the self-alignment accuracy is greatly improved, mean-while the self-alignment time is widely shortened.  相似文献   
63.
交叉销售是一种经常采用的市场营销方式,对提高销售商市场占有率起着重要作用. 考虑特价商品与相关商品存在交叉销售,其需求与价格和库存水平有关,有现货时会促进相关商品销售,缺货时顾客等待意愿受价格和时间共同影响,构造了一个新的短缺量滞后供给分数,建立了相应的经济订货批量模型(economic order quantity model,简称EOQ模型). 从理论上分析了模型唯一最优解存在的条件和相关的管理启示. 采用数值仿真研究了价格和时间敏感因子、需求相关因子等参数对销售商订货策略和平均利润的影响. 研究结果表明:特价商品销售价、有现货和缺货时间均存在一个合理范围,其中销售价在一定条件下不能超过某一固定值,缺货时间存在一个下限,当价格和时间敏感因子、需求相关因子和两种商品销售价与采购价之差增加时,应尽量减少缺货时间;当特价商品销售价高于该固定值时,有现货和缺货时间存在一个上限;在一定条件下,提高特价商品销售价会减少销售商整体收益.  相似文献   
64.
To study the effect of cooperative advertising on the supply chain of deteriorating items, this paper establishes a Stackelberg game model for a two-echelon deteriorating items supply chain composed of one manufacturer and one retailer under a given support program with an exogenous participation rate. The manufacturer as the leader determines the wholesale price and production rate, and the retailer as the follower determines the retail price and advertising strategies. The strategies of the players under the decentralized scenario and the centralized scenario are respectively characterized. Numerical simulations and sensitivity analysis are conducted to gain some managerial insights. It is shown that the pricing, advertising and production strategies are negatively correlated to deteriorating coefficient, and both the profit and the channel efficiency decrease with deteriorating coefficient; The interaction between price, advertising investment and production rate results in a higher retail price of the centralized channel compared to that of the decentralized channel; Implementing the cooperative advertising program does improve the performance of the supply chain in some cases and the participation rate roughly at 0.5 is most preferable, but it is also possible to distort incentive and damage the channel performance when the participation rate reaches a relatively high level.  相似文献   
65.
反恐斗争是一种特殊的军事斗争形式,是当前军事训练领域的一个重要内容。为满足国内城市“反恐、防恐”的需要,满足驻城部队军官指挥行动训练的需求,我们研制了防卫行动指挥训练模拟系统。首先介绍了该训练模拟系统要达到的总体战技指标、实现的主要功能,然后给出具体实现的硬件构成和各相应的模块子系统、各个分系统的相互关系,以及电台模拟与实时语音通信技术,最后介绍了系统研制过程当中所采用的关键技术。该系统在某装甲步兵分队应用后,反映效果较好、收效明显,对驻城区部队的“反恐”训练具有很强的推动作用。  相似文献   
66.
粒子群算法在投资组合中的应用   总被引:3,自引:0,他引:3  
张波  陈睿君  路璐 《系统工程》2007,25(8):108-110
投资组合面临现实证券市场中大量数据,求解组合模型是一个非线性整数规划问题,传统数学规划算法难以有效求解。为此,本文将粒子群算法应用到基于VaR的投资组合模型中,并通过上海证券交易所的实际数据进行计算机模拟,结果说明该算法所求最优投资组合是实用的和有效的。  相似文献   
67.
A frequency-domain-based sufficient condition is derived to guarantee the globally asymptotic stability of the simplest Takagi-Sugeno (T-S) fuzzy control system by using the circle criterion. The analysis is performed in the frequency domain, and hence the condition is of great significance when the frequency-response method, which is widely used in the linear control theory and practice, is employed to synthesize the simplest T-S fuzzy controller. Besides, this sufficient condition is featured by a graphical interpretation, which makes the condition straightforward to be used. Comparisons are drawn between the performance of the simplest T-S fuzzy controller and that of the linear compensator. Two numerical examples are presented to demonstrate how this sufficient condition can be applied to both stable and unstable plants.  相似文献   
68.
Energy saving is the most important issue in research and development for wireless sensor networks. A power control mechanism can reduce the power consumption of the whole network.Because the character of wireless sensor networks is restrictive energy,this paper proposes a distributed power control algorithm based on game theory for wireless sensor networks which objects of which are reducing power consumption and decreasing overhead and increasing network lifetime.The game theory and OPNET simulation shows that the power control algorithm converges to a Nash Equilibrium when decisions are updated according to a better response dynamic.  相似文献   
69.
In this paper, we investigate the global controllability of a class of n-dimensional affine nonlinear systems with n- 1 controls and constant control matrix. A necessary and sufficient condition for its global controllability has been obtained by using the methods recently developed. Furthermore, we generalize the above result to a class of affine nonlinear systems with a block-triangular-like structure. Finally, we will give three examples to show the applications of our results.  相似文献   
70.
针对当前车底阴影分割算法在复杂环境下鲁棒性较差以及最大类间方差(maximum between class variance, MBCV)多阈值分割算法不能自动确定阈值个数的问题,提出利用峰值自适应方法自动确定MBCV多阈值分割算法中阈值个数;然后,以阈值的个数为粒子群优化算法(particle swarm optimization, PSO)中粒子的维数,提出了一种改进的PSO MBCV算法的车底阴影分割。实验结果表明,该算法能有较低的误分类误差,能有效地分割出车底阴影。  相似文献   
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