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121.
A directed searching optimization algorithm (DSO) is proposed to solve constrained optimization problems in this paper. The proposed algorithm includes two important operations — position updating and genetic mutation. Position updating enables the non-best solution vectors to mimic the best one, which is beneficial to the convergence of the DSO; genetic mutation can increase the diversity of individuals, which is beneficial to preventing the premature convergence of the DSO. In addition, we adopt the penalty function method to balance objective and constraint violations. We can obtain satisfactory solutions for constrained optimization problems by combining the DSO and the penalty function method. Experimental results indicate that the proposed algorithm can be an efficient alternative on solving constrained optimization problems.  相似文献   
122.
变论域模糊控制器的控制函数被"复制"到后代中,往往存在着"失真"现象,这种现象的后果是造成算法本身的误差.针对这一问题,本文提出了一种基于Q学习算法的变论域模糊控制优化设计方法.本算法在变论域模糊控制算法基础上提出了一种利用伸缩因子、等比因子相互协调来调整论域的构想,且通过用Q学习算法来寻优参数使控制器性能指标最小,使其在控制过程中能够降低"失真率",从而进一步提高控制器性能.最后,把算法运用于一个二阶系统与非最小相位系统,实验表明,该算法不但具有很好的鲁棒性及动态性能,且与变论域模糊控制器比较起来,其控制性能也更加提高.  相似文献   
123.
研究开发了一种用于控制手柄的自然接触传感器组.该传感器组能够实时地测量皮肤血流容积、皮肤导电性、皮肤温度和握力等人体生理信号,同时不会改变和打扰人原来的工作状态.传感器的设计是基于自然接触理念,通过包覆的方式安置到控制手柄上,以保证人和传感器的自然接触,包覆有此类传感器的手柄称为智能控制手柄,实验结果显示智能控制手柄具...  相似文献   
124.
A structured-based neural network (NN) with backpropagation through structure (BPTS) algorithm is conducted for image classification in organizing a large image database, which is a challenging problem under investigation. Many factors can affect the results of image classification. One of the most important factors is the architecture of a NN, which consists of input layer, hidden layer and output layer. In this study, only the numbers of nodes in hidden layer (hidden nodes) of a NN are considered. Other factors are kept unchanged. Two groups of experiments including 2,940 images in each group are used for the analysis. The assessment of the effects for the first group is carried out with features described by image intensities, and, the second group uses features described by wavelet coefficients. Experimental results demonstrate that the effects of the numbers of hidden nodes on the reliability of classification are significant and non-linear. When the number of hidden nodes is 17, the classification rate on training set is up to 95%, and arrives at 90% on the testing set. The results indicate that 17 is an appropriate choice for the number of hidden nodes for the image classification when a structured-based NN with BPTS algorithm is applied.  相似文献   
125.
磁盘的随机I/O延时制约了存储系统的性能提高,具备高性能随机I/O特性的固态盘(solid state disk,SSD)逐渐成为关注的热点.分析了磁盘、Flash型SSD以及DRAM型SSD三类设备不同的性能特点,讨论了SSD存储加速技术的研究现状,提出了一种面向Lustre文件系统的固态盘存储加速系统架构,介绍和分析了各模块的构成与原理,提出了对象迁移策略.  相似文献   
126.
电子信息系统中信息传输控制技术   总被引:1,自引:1,他引:0       下载免费PDF全文
信息传输控制技术是决定信息正确传输的关键,该文针对目前电子信息系统中信息传输的现状和特点,提出构件化网络传输控制服务软件的设计方法,采用相关信息传输控制技术,建立信息传输组件架构和传输控制机制应用于工程实践。结果证明,该技术设计解决了目前困扰信息传输的相关实际问题,在提高信息传输的灵活性、实时高效性和可靠性等方面取得了明显的效果。  相似文献   
127.
The profile of the nano-mold can also influence the replication precision of the final 2D polymer nanochannels. In the present work, the aspect ratio of the nano-mold, the duty ratio of the nano-mold, and the thickness ratio were investigated by numerical simulation method. The replication precision of the 2D polymer nanochannels is evaluated by imprinting ratio. The simulation results show that the lower aspect ratio and duty ratio is associated with higher imprinting ratio. However, the imprinting ratio increases with the thickness ratio at beginning and then keeps nearly unchanged as the thickness ratio continuously increases. The proper thickness ratio is two. The imprinting temperature and pressure were also optimized according the imprinting ratio. The simulation results show that the optimal imprinting temperature and pressure were 120 °C and 1.5 MPa, respectively.  相似文献   
128.
Lu  Gui-Fu  Zou  Jian  Wang  Yong  Wang  Zhongqun 《Multimedia Tools and Applications》2017,76(14):15801-15816
Multimedia Tools and Applications - Null space based linear discriminant analysis (NSLDA) is a well-known feature extraction method, which can make use of the most discriminant information in the...  相似文献   
129.
A broadcasting multiple blind signature scheme based on quantum GHZ entanglement has been presented recently. It is said that the scheme’s unconditional security is guaranteed by adopting quantum key preparation, quantum encryption algorithm and quantum entanglement. In this paper, we prove that each signatory can get the signed message just by an intercept–resend attack. Then, we show there still exist some participant attacks and external attacks. Specifically, we verify the message sender Alice can impersonate each signatory to sign the message at will, and so is the signature collector Charlie. Also, we demonstrate that the receiver Bob can forge the signature successfully, and with respect to the external attacks, the eavesdropper Eve can modify the signature at random. Besides, we discover Eve can change the signed message at random, and Eve can impersonate Alice as the message sender without being discovered. In particular, we propose an improved scheme based on the original one and show that it is secure against not only the attacks mentioned above but also some collusion attacks.  相似文献   
130.
This paper studies the mean square quadratic (MSQ) detectability for multi-output networked systems over finite-state digital block-fading channels. The packet-loss rate of each digital fading channel depends on the channel power gain, as well as packet length and power level used for transmission. A finite-state random process is introduced to model time-varying fading channels, which characterizes various configurations of physical communication environment and/or different channel fading amplitudes. Necessary and sufficient conditions for MSQ detectability over finite-state Markov digital block-fading channels are given in the form of algebraic Riccati equations or linear matrix inequalities (LMIs). The estimation gain is given as a function of estimated/observed channel state. In addition, explicit conditions on network for MSQ detectability over finite-state independent identically distributed (i.i.d.) digital block-fading channels are presented in terms of the unstable poles of the multi-output plant. Finally, an application to Gilbert-Elliott channels (GECs) is provided to demonstrate the derived results.  相似文献   
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