Discrete Dynamics in Nature and Society http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Complexity Quantification for Overhead Transmission Line Emergency Repair Scheme via a Graph Entropy Method Improved with Petri Net and AHP Weighting Method Sun, 21 Dec 2014 14:34:39 +0000 http://www.hindawi.com/journals/ddns/2014/761507/ According to the characteristics of emergency repair in overhead transmission line accidents, a complexity quantification method for emergency repair scheme is proposed based on the entropy method in software engineering, which is improved by using group AHP (analytical hierarchical process) method and Petri net. Firstly, information structure chart model and process control flowchart model could be built by Petri net. Then impact factors on complexity of emergency repair scheme could be quantified into corresponding entropy values, respectively. Finally, by using group AHP method, weight coefficient of each entropy value would be given before calculating the overall entropy value for the whole emergency repair scheme. By comparing group AHP weighting method with average weighting method, experiment results for the former showed a stronger correlation between quantified entropy values of complexity and the actual consumed time in repair, which indicates that this new method is more valid. Jing Zhou, Cunbin Li, Weihua Shen, and Ye Zhang Copyright © 2014 Jing Zhou et al. All rights reserved. Shifting Control Algorithm for a Single-Axle Parallel Plug-In Hybrid Electric Bus Equipped with EMT Sun, 21 Dec 2014 10:09:12 +0000 http://www.hindawi.com/journals/ddns/2014/618587/ Combining the characteristics of motor with fast response speed, an electric-drive automated mechanical transmission (EMT) is proposed as a novel type of transmission in this paper. Replacing the friction synchronization shifting of automated manual transmission (AMT) in HEVs, the EMT can achieve active synchronization of speed shifting. The dynamic model of a single-axle parallel PHEV equipped with the EMT is built up, and the dynamic properties of the gearshift process are also described. In addition, the control algorithm is developed to improve the shifting quality of the PHEV equipped with the EMT in all its evaluation indexes. The key techniques of changing the driving force gradient in preshifting and shifting compensation phases as well as of predicting the meshing speed in the gear meshing phase are also proposed. Results of simulation, bench test, and real road test demonstrate that the proposed control algorithm can reduce the gearshift jerk and the power interruption time noticeably. Yunyun Yang, Sen Wu, and Xiang Fu Copyright © 2014 Yunyun Yang et al. All rights reserved. Three-Level Supply Chain Coordination under Disruptions Based on Revenue-Sharing Contract with Price Dependent Demand Sun, 21 Dec 2014 00:10:28 +0000 http://www.hindawi.com/journals/ddns/2014/464612/ Considering the market demand is stochastic and dependent on price, this paper shows that the revenue-sharing contract could coordinate a three-level supply chain consisting of one manufacturer, one distributor, and one retailer under normal environment. However, the original revenue-sharing contract cannot coordinate the supply chain under disruptions in circumstances of certain incidents leading to significant changes in market demand and causing additional deviation costs. To solve the problem, this essay introduces two improved forms of revenue-sharing contract: a mixed contract form based on a quantity discount policy and a pure form, which are characterized by antidisruption ability. The model of improved revenue-sharing contract is optimized when the market demand is in the additive form or in the multiplicative form with price dependent demand. Formulas are given to calculate the optimal contract parameters. Finally, this essay demonstrates the accuracy of the model of improved revenue-sharing contract with the help of numerical examples. Qinghua Pang, Yuer Chen, and Yulu Hu Copyright © 2014 Qinghua Pang et al. All rights reserved. A Hybrid Artificial Bee Colony Algorithm for the Service Selection Problem Wed, 17 Dec 2014 07:04:33 +0000 http://www.hindawi.com/journals/ddns/2014/835071/ To tackle the QoS-based service selection problem, a hybrid artificial bee colony algorithm called -ABC is proposed, which incorporates the ant colony optimization mechanism into the artificial bee colony optimization process. In this algorithm, a skyline query process is used to filter the candidates related to each service class, which can greatly shrink the search space in case of not losing good candidates, and a flexible self-adaptive varying construct graph is designed to model the search space based on a clustering process. Then, based on this construct graph, different foraging strategies are designed for different groups of bees in the swarm. Finally, this approach is evaluated experimentally using different standard real datasets and synthetically generated datasets and compared with some recently proposed related service selection algorithms. It reveals very encouraging results in terms of the quality of solutions. Changsheng Zhang and Bin Zhang Copyright © 2014 Changsheng Zhang and Bin Zhang. All rights reserved. Critical Blow-Up and Global Existence for Discrete Nonlinear p-Laplacian Parabolic Equations Sun, 14 Dec 2014 09:18:47 +0000 http://www.hindawi.com/journals/ddns/2014/716327/ The goal of this paper is to investigate the blow-up and the global existence of the solutions to the discrete p-Laplacian parabolic equation , , , , , depending on the parameters and . Besides, we provide several types of the comparison principles to this equation, which play a key role in the proof of the main theorems. In addition, we finally give some numerical examples which exploit the main results. Soon-Yeong Chung Copyright © 2014 Soon-Yeong Chung. All rights reserved. Lifecycle-Based Swarm Optimization Method for Numerical Optimization Thu, 11 Dec 2014 09:30:21 +0000 http://www.hindawi.com/journals/ddns/2014/892914/ Bioinspired optimization algorithms have been widely used to solve various scientific and engineering problems. Inspired by biological lifecycle, this paper presents a novel optimization algorithm called lifecycle-based swarm optimization (LSO). Biological lifecycle includes four stages: birth, growth, reproduction, and death. With this process, even though individual organism died, the species will not perish. Furthermore, species will have stronger ability of adaptation to the environment and achieve perfect evolution. LSO simulates Biological lifecycle process through six optimization operators: chemotactic, assimilation, transposition, crossover, selection, and mutation. In addition, the spatial distribution of initialization population meets clumped distribution. Experiments were conducted on unconstrained benchmark optimization problems and mechanical design optimization problems. Unconstrained benchmark problems include both unimodal and multimodal cases the demonstration of the optimal performance and stability, and the mechanical design problem was tested for algorithm practicability. The results demonstrate remarkable performance of the LSO algorithm on all chosen benchmark functions when compared to several successful optimization techniques. Hai Shen, Yunlong Zhu, and Xiaodan Liang Copyright © 2014 Hai Shen et al. All rights reserved. Reconstruction of Dynamical Forecasting Model between Western Pacific Subtropical High Area Index and Its Summer Monsoon Impact Factors Based on the Improved Self-Memorization Principle Wed, 10 Dec 2014 00:10:57 +0000 http://www.hindawi.com/journals/ddns/2014/867632/ With the objective of tackling the problem of inaccurate long-term western pacific subtropical high (WPSH) forecasts, based on the concept of dynamical model reconstruction and improved self-memorization principle, a new dynamical forecasting model of WPSH area (SI) index is developed. To overcome the problem of single initial prediction value, the largest Lyapunov exponent is introduced to improve the traditional self-memorization function, making it more appropriate to describe the chaotic systems, such as WPSH; the equation reconstruction by actual data is used as its dynamical core to overcome the problem of relatively simple dynamical core. The developed dynamical forecasting model of SI index is used to predict WPSH strength in the long term. Through 10 experiments of the WPSH abnormal years, forecast results within 25 days are found to be good, with a correlation coefficient of about 0.80 and root mean square error under 8%, showing that the improved model has satisfactory long-term forecasting results. In particular the aberrance of the subtropical high can be drawn and forecast. It is acknowledged that mechanism for the occurrence and development of WPSH is complex, so the discussion in this paper is therefore exploratory. Mei Hong, Ren Zhang, Xi Chen, Shanshan Ge, Chengzu Bai, and Vijay P. Singh Copyright © 2014 Mei Hong et al. All rights reserved. On Exponential Stabilizability for a Class of Switched Nonlinear Systems with Mixed Time-Varying Delays Thu, 04 Dec 2014 12:03:48 +0000 http://www.hindawi.com/journals/ddns/2014/427893/ We study the exponential stabilizability for a class of switched nonlinear systems with mixed time-varying delays. By using a new technique developed for positive systems, we design the average dwell time switching under which the switched nonlinear system is exponentially stable for any bounded delays. Finally, numerical examples are worked out to illustrate the main theoretical result. Jie Qi and Yuangong Sun Copyright © 2014 Jie Qi and Yuangong Sun. All rights reserved. Existence and Uniqueness of Positive Solitons for a Second-Order Difference Equation Tue, 02 Dec 2014 12:29:29 +0000 http://www.hindawi.com/journals/ddns/2014/503496/ A discrete logistic steady-state equation with both positive and negative birth rate of population will be considered. By using sub- and upper-solution method, the existence of bounded positive solutions and the existence and uniqueness of positive solitons will be established. To this end, the Dirichlet eigenvalue problem with positive and negative coefficients is considered, and a general sub- and upper-solution theorem is also obtained. Xinfu Li, Guang Zhang, and Ying Wang Copyright © 2014 Xinfu Li et al. All rights reserved. Nonlinear Analysis on Traffic Flow Based on Catastrophe and Chaos Theory Thu, 27 Nov 2014 12:38:21 +0000 http://www.hindawi.com/journals/ddns/2014/535167/ We applied catastrophe and chaos theory to analyze the traffic nonlinear characteristics of expressway condition. Catastrophe theory was generally used to explore the mathematical relationships among the traffic data collected from highway conditions, which could not be appropriate for the urban expressway conditions. Traffic flow data collected from the 3rd ring road expressway in Beijing was used to build flow-density model and speed-density Greenshields model. Then the density was discussed based on the traffic wave speed function with cusp catastrophe theory; in particular, density conditions on median lanes and shoulder lanes were deeply discussed. Meanwhile the chaotic characteristics were analyzed based on the traffic temporal sequence data collected from 29 detectors located at the 3rd ring road expressway, and C-C method was used to reconstruct the phase space and the largest Lyapunov exponents were estimated by Wolf method and the small data sets method. The results indicated that the traffic operation catastrophe density on the median lanes was a bit higher than that on the shoulder lanes; additionally chaotic characteristics obviously existed in the local corridor composed of 29 detectors in the 3rd ring road expressway traffic flow system. Jian Gu and Shuyan Chen Copyright © 2014 Jian Gu and Shuyan Chen. All rights reserved. An Effective Privacy-Preserving Algorithm Based on Logistic Map and Rubik’s Cube Transformation Thu, 27 Nov 2014 12:14:41 +0000 http://www.hindawi.com/journals/ddns/2014/178585/ Security and privacy issues present a strong barrier for users to adapt to cloud storage systems. In this paper, a new algorithm for data splitting called EPPA is presented to strengthen the confidentiality of data by two-phase process. In EPPA, data object is organized to be several Rubik’s cubes executed for several rounds transformation at the first phase. In every round, chaotic logistic maps generate pseudorandom sequences to cover the plaintext by executing Exclusive-OR operation to form the cipher. Then logistic map is used to create rotation policies to scramble data information based on Rubik’s cube transformation. At the second phase, all cubes are unfolded and combined together as a cross-shaped cube, which will be partitioned into a few data fragments to guarantee that every fragment does not contain continuous bytes. These fragments are stored on randomly chosen servers within cloud environment. Analyses and experiments show that this approach is efficient and useable for the confidentiality of user data in cloud storage system. Wenbin Yao, Pengdi Ye, and Xiaoyong Li Copyright © 2014 Wenbin Yao et al. All rights reserved. A Simple Gaussian Measurement Bound for Exact Recovery of Block-Sparse Signals Wed, 26 Nov 2014 13:56:23 +0000 http://www.hindawi.com/journals/ddns/2014/104709/ We present a probabilistic analysis on conditions of the exact recovery of block-sparse signals whose nonzero elements appear in fixed blocks. We mainly derive a simple lower bound on the necessary number of Gaussian measurements for exact recovery of such block-sparse signals via the mixed norm minimization method. In addition, we present numerical examples to partially support the correctness of the theoretical results. The obtained results extend those known for the standard minimization and the mixed minimization methods to the mixed minimization method in the context of block-sparse signal recovery. Zhi Han, Jianjun Wang, Jia Jing, and Hai Zhang Copyright © 2014 Zhi Han et al. All rights reserved. Radial Basis Function Neural Network with Particle Swarm Optimization Algorithms for Regional Logistics Demand Prediction Wed, 26 Nov 2014 12:48:35 +0000 http://www.hindawi.com/journals/ddns/2014/414058/ Regional logistics prediction is the key step in regional logistics planning and logistics resources rationalization. Since regional economy is the inherent and determinative factor of regional logistics demand, it is feasible to forecast regional logistics demand by investigating economic indicators which can accelerate the harmonious development of regional logistics industry and regional economy. In this paper, the PSO-RBFNN model, a radial basis function neural network (RBFNN) combined with particle swarm optimization (PSO) algorithm, is studied. The PSO-RBFNN model is trained by indicators data in a region to predict the regional logistics demand. And the corresponding results indicate the model’s applicability and potential advantages. Zhineng Hu, Yixin Zhang, and Liming Yao Copyright © 2014 Zhineng Hu et al. All rights reserved. Adaptive Synchronization between Fractional-Order Chaotic Real and Complex Systems with Unknown Parameters Wed, 26 Nov 2014 11:46:01 +0000 http://www.hindawi.com/journals/ddns/2014/484039/ The complex modified projective synchronization (CMPS) between fractional-order chaotic real and complex systems is investigated for the first time. The parameters of both master and slave systems are assumed to be unknown in advance; moreover, the slave system is perturbed by unknown but bounded external disturbances. The master and slave systems that achieved CMPS can be synchronized up to a complex constant matrix. On the basis of frequency distributed model of fractional integrator and Lyapunov stability theory, a robust adaptive control law is designed to realize the CMPS for two different types of fractional-order chaotic systems. Meanwhile, to deal with these unknown parameters, some fractional-order type parametric update laws are provided. An example is given to demonstrate the effectiveness and feasibility of the proposed synchronization scheme. Xiaomin Tian Copyright © 2014 Xiaomin Tian. All rights reserved. A Novel Method for Decoding Any High-Order Hidden Markov Model Sun, 23 Nov 2014 09:13:06 +0000 http://www.hindawi.com/journals/ddns/2014/231704/ This paper proposes a novel method for decoding any high-order hidden Markov model. First, the high-order hidden Markov model is transformed into an equivalent first-order hidden Markov model by Hadar’s transformation. Next, the optimal state sequence of the equivalent first-order hidden Markov model is recognized by the existing Viterbi algorithm of the first-order hidden Markov model. Finally, the optimal state sequence of the high-order hidden Markov model is inferred from the optimal state sequence of the equivalent first-order hidden Markov model. This method provides a unified algorithm framework for decoding hidden Markov models including the first-order hidden Markov model and any high-order hidden Markov model. Fei Ye and Yifei Wang Copyright © 2014 Fei Ye and Yifei Wang. All rights reserved. A Scatter Search Approach for Multiobjective Selective Disassembly Sequence Problem Tue, 18 Nov 2014 09:31:44 +0000 http://www.hindawi.com/journals/ddns/2014/756891/ Disassembly sequence has received much attention in recent years. This work proposes a multiobjective optimization of model for selective disassembly sequences and maximizing disassembly profit and minimizing disassembly time. An improved scatter search (ISS) is adapted to solve proposed multiobjective optimization model, which embodies diversification generation of initial solutions, crossover combination operator, the local search strategy to improve the quality of new solutions, and reference set update method. To analyze the effect on the performance of ISS, simulation experiments are conducted on different products. The validity of ISS is verified by comparing the optimization effects of ISS and nondominated sorting genetic algorithm (NSGA-II). Xiwang Guo and Shixin Liu Copyright © 2014 Xiwang Guo and Shixin Liu. All rights reserved. Dynamic Traffic Network Model and Time-Dependent Braess’ Paradox Mon, 17 Nov 2014 12:26:48 +0000 http://www.hindawi.com/journals/ddns/2014/802129/ We propose a dynamic traffic network model and give the equilibrium condition and the equivalent variational inequality of the network. In this model, instead of the influence of inflow rate and output rate on the link congestion, the influence of the adjacent links at the same paths is considered; in this case, the equivalence between the equilibrium condition and the variational inequality is proved. Then we take an example about the paradox using the variational inequality and find that the probability and the severity that Braess’ paradox occurs change with the influence of other links changing. Subsequently, we discuss the influence of other links on whether the adding link works under the dynamic system optimal. At last, we give the relationship between the total congestion under dynamic user equilibrium and that under dynamic system optimal. The results imply that we should take some methods and adjust the interaction between links rationally with the dynamic change of traffic situations. Chunxue Zhao Copyright © 2014 Chunxue Zhao. All rights reserved. Codynamics of Four Variables Involved in Dengue Transmission and Its Control by Community Intervention: A System of Four Difference Equations Mon, 17 Nov 2014 11:31:49 +0000 http://www.hindawi.com/journals/ddns/2014/101965/ In the case of Dengue transmission and control, the interaction of nature and society is captured by a system of difference equations. For the purpose of studying the dynamics of these interactions, four variables involved in a Dengue epidemic, proportion of infected people (), number of mosquitoes involved in transmission (), mosquito habitats (), and population awareness (), are linked in a system of difference equations: , , , and , . The constraints have socioecological meaning. The initial conditions are such that , the parameters , and the parameters ,  ,  , and are positive. The paper is concerned with the analysis of solutions of the above system for . We studied the global asymptotic stability of the degenerate equilibrium. We also propose extensions of the above model and some open problems. We explored the role of memory in community awareness by numerical simulations. When the memory parameter is large, the proportion of infected people decreases and stabilizes at zero. Below a critical point we observe periodic oscillations. T. Awerbuch-Friedlander, Richard Levins, and M. Predescu Copyright © 2014 T. Awerbuch-Friedlander et al. All rights reserved. The Bifurcation and Control of a Single-Species Fish Population Logistic Model with the Invasion of Alien Species Sun, 16 Nov 2014 12:45:20 +0000 http://www.hindawi.com/journals/ddns/2014/548384/ The objective of this paper is to study systematically the bifurcation and control of a single-species fish population logistic model with the invasion of alien species based on the theory of singular system and bifurcation. It regards Spartina anglica as an invasive species, which invades the fisheries and aquaculture. Firstly, the stabilities of equilibria in this model are discussed. Moreover, the sufficient conditions for existence of the trans-critical bifurcation and the singularity induced bifurcation are obtained. Secondly, the state feedback controller is designed to eliminate the unexpected singularity induced bifurcation by combining harvested effort with the purification capacity. It obviously inhibits the switch of population and makes the system stable. Finally, the numerical simulation is proposed to show the practical significance of the bifurcation and control from the biological point of view. Yi Zhang, Qiaoling Zhang, Jinghao Li, and Qingling Zhang Copyright © 2014 Yi Zhang et al. All rights reserved. Stability of a Class of Fractional-Order Nonlinear Systems Sun, 16 Nov 2014 06:15:50 +0000 http://www.hindawi.com/journals/ddns/2014/724270/ In this letter stability analysis of fractional order nonlinear systems is studied. Some new sufficient conditions on the local (globally) asymptotic stability for a class of fractional order nonlinear systems with order are proposed by using properties of Mittag-Leffler function and the Gronwall inequality. And the corresponding stabilization criteria are also given. The numerical simulations of two systems with order and two systems with order illustrate the effectiveness and universality of the proposed approach. Tianzeng Li and Yu Wang Copyright © 2014 Tianzeng Li and Yu Wang. All rights reserved. Powertrain Matching and Optimization of Dual-Motor Hybrid Driving System for Electric Vehicle Based on Quantum Genetic Intelligent Algorithm Thu, 13 Nov 2014 14:36:04 +0000 http://www.hindawi.com/journals/ddns/2014/956521/ In order to increase the driving range and improve the overall performance of all-electric vehicles, a new dual-motor hybrid driving system with two power sources was proposed. This system achieved torque-speed coupling between the two power sources and greatly improved the high performance working range of the motors; at the same time, continuously variable transmission (CVT) was achieved to efficiently increase the driving range. The power system parameters were determined using the “global optimization method”; thus, the vehicle’s dynamics and economy were used as the optimization indexes. Based on preliminary matches, quantum genetic algorithm was introduced to optimize the matching in the dual-motor hybrid power system. Backward simulation was performed on the combined simulation platform of Matlab/Simulink and AVL-Cruise to optimize, simulate, and verify the system parameters of the transmission system. Results showed that quantum genetic algorithms exhibited good global optimization capability and convergence in dealing with multiobjective and multiparameter optimization. The dual-motor hybrid-driving system for electric cars satisfied the dynamic performance and economy requirements of design, efficiently increasing the driving range of the car, having high performance, and reducing energy consumption of 15.6% compared with the conventional electric vehicle with single-speed reducers. Yong Wang and Dongye Sun Copyright © 2014 Yong Wang and Dongye Sun. All rights reserved. Levenberg-Marquardt Algorithm for Mackey-Glass Chaotic Time Series Prediction Tue, 11 Nov 2014 07:57:34 +0000 http://www.hindawi.com/journals/ddns/2014/193758/ For decades, Mackey-Glass chaotic time series prediction has attracted more and more attention. When the multilayer perceptron is used to predict the Mackey-Glass chaotic time series, what we should do is to minimize the loss function. As is well known, the convergence speed of the loss function is rapid in the beginning of the learning process, while the convergence speed is very slow when the parameter is near to the minimum point. In order to overcome these problems, we introduce the Levenberg-Marquardt algorithm (LMA). Firstly, a rough introduction is given to the multilayer perceptron, including the structure and the model approximation method. Secondly, we introduce the LMA and discuss how to implement the LMA. Lastly, an illustrative example is carried out to show the prediction efficiency of the LMA. Simulations show that the LMA can give more accurate prediction than the gradient descent method. Junsheng Zhao, Yongmin Li, Xingjiang Yu, and Xingfang Zhang Copyright © 2014 Junsheng Zhao et al. All rights reserved. A Case-Based Reasoning Method for Remanufacturing Process Planning Tue, 11 Nov 2014 06:30:26 +0000 http://www.hindawi.com/journals/ddns/2014/168631/ Remanufacturing is a practice of growing importance due to its increasing environmental and economic benefits. Process planning plays a critical role in realizing a successful remanufacturing strategy. This paper presents a case-based reasoning method for remanufacturing process planning, which allows a process planner to rapidly retrieve, reuse, revise, and retain the solutions to past process problems. In the proposed method, influence factors including essential characteristics, failure characteristics, and remanufacturing processing characteristics are identified, and the local similarity of influence factors between the new case and the past cases is determined by nearest neighbor matching method, and then the vector of correction factor for local similarity is utilized in the nearest neighbor algorithm to improve the accuracy and effectiveness of case searching. To assess the usefulness and practicality of the proposed method, an illustrative example is given and the results are discussed. Fan Zhou, Zhigang Jiang, Hua Zhang, and Yan Wang Copyright © 2014 Fan Zhou et al. All rights reserved. Discrete Dynamic Gaming Models in Supply Chain Management and Project Management Mon, 10 Nov 2014 00:00:00 +0000 http://www.hindawi.com/journals/ddns/2014/960239/ Jun Zhuang, Xiaolin Xu, and Gangshu (George) Cai Copyright © 2014 Jun Zhuang et al. All rights reserved. Unsupervised SAR Image Segmentation Based on a Hierarchical TMF Model in the Discrete Wavelet Domain for Sea Area Detection Tue, 04 Nov 2014 08:59:32 +0000 http://www.hindawi.com/journals/ddns/2014/354704/ Unsupervised synthetic aperture radar (SAR) image segmentation is a fundamental preliminary processing step required for sea area detection in military applications. The purpose of this step is to classify large image areas into different segments to assist with identification of the sea area and the ship target within the image. The recently proposed triplet Markov field (TMF) model has been successfully used for segmentation of nonstationary SAR images. This letter presents a hierarchical TMF model in the discrete wavelet domain of unsupervised SAR image segmentation for sea area detection, which we have named the wavelet hierarchical TMF (WHTMF) model. The WHTMF model can precisely capture the global and local image characteristics in the two-pass computation of posterior distribution. The multiscale likelihood and the multiscale energy function are constructed to capture the intrascale and intrascale dependencies in a random field (). To model the SAR data related to radar backscattering sources, the Gaussian distribution is utilized. The effectiveness of the proposed model for SAR image segmentation is evaluated using synthesized and real SAR data. Jiajing Wang, Shuhong Jiao, Lianyang Shen, Zhenyu Sun, and Lin Tang Copyright © 2014 Jiajing Wang et al. All rights reserved. Movement Control in Recovering UUV Based on Two-Stage Discrete T-S Fuzzy Model Tue, 04 Nov 2014 08:00:42 +0000 http://www.hindawi.com/journals/ddns/2014/362787/ A two-stage discrete T-S fuzzy model controller, which is formed by a motion controller and a dynamic controller connected in series, is presented to solve UUV (unmanned underwater vehicle) movement control problem for recovering. The motion controller is designed based on the uncertain T-S model and the concept of discrete fuzzy vector. The position error between UUV and moving platform as the input of the motion controller is converted into the speed commands of UUV at the next time. The dynamic controller design is based on the theory of fuzzy region model and a relaxed condition for Lyapunov stabilization function is derived in the form of linear matrix inequalities, which generate force and torque required to complete the recovery task. The feasibility and the efficiency of the proposed control scheme are illustrated through the simulations that UUV follows moving platform. Zheping Yan, Bing Hao, Yibo Liu, and Shuping Hou Copyright © 2014 Zheping Yan et al. All rights reserved. A Dufort-Frankel Difference Scheme for Two-Dimensional Sine-Gordon Equation Wed, 29 Oct 2014 09:08:21 +0000 http://www.hindawi.com/journals/ddns/2014/784387/ A standard Crank-Nicolson finite-difference scheme and a Dufort-Frankel finite-difference scheme are introduced to solve two-dimensional damped and undamped sine-Gordon equations. The stability and convergence of the numerical methods are considered. To avoid solving the nonlinear system, the predictor-corrector techniques are applied in the numerical methods. Numerical examples are given to show that the numerical results are consistent with the theoretical results. Zongqi Liang, Yubin Yan, and Guorong Cai Copyright © 2014 Zongqi Liang et al. All rights reserved. Sampled-Data Consensus for High-Order Multiagent Systems under Fixed and Randomly Switching Topology Wed, 22 Oct 2014 11:26:58 +0000 http://www.hindawi.com/journals/ddns/2014/598965/ This paper studies the sampled-data based consensus of multiagent system with general linear time-invariant dynamics. It focuses on looking for a maximum allowable sampling period bound such that as long as the sampling period is less than this bound, there always exist linear consensus protocols solving the consensus problem. Both fixed and randomly switching topologies are considered. For systems under fixed topology, a necessary and sufficient sampling period bound is obtained for single-input multiagent systems, and a sufficient allowable bound is proposed for multi-input systems by solving the optimal control problem of certain system with uncertainty. For systems under randomly switching topologies, tree-type and complete broadcasting network with Bernoulli packet losses are discussed, and explicit allowable sampling period bounds are, respectively, given based on the unstable eigenvalues of agent’s system matrix and packet loss probability. Numerical examples are given to illustrate the results. Niu Jie and Li Zhong Copyright © 2014 Niu Jie and Li Zhong. All rights reserved. A Constrained Algorithm Based NMFα for Image Representation Wed, 22 Oct 2014 07:57:08 +0000 http://www.hindawi.com/journals/ddns/2014/179129/ Nonnegative matrix factorization (NMF) is a useful tool in learning a basic representation of image data. However, its performance and applicability in real scenarios are limited because of the lack of image information. In this paper, we propose a constrained matrix decomposition algorithm for image representation which contains parameters associated with the characteristics of image data sets. Particularly, we impose label information as additional hard constraints to the α-divergence-NMF unsupervised learning algorithm. The resulted algorithm is derived by using Karush-Kuhn-Tucker (KKT) conditions as well as the projected gradient and its monotonic local convergence is proved by using auxiliary functions. In addition, we provide a method to select the parameters to our semisupervised matrix decomposition algorithm in the experiment. Compared with the state-of-the-art approaches, our method with the parameters has the best classification accuracy on three image data sets. Chenxue Yang, Tao Li, Mao Ye, Zijian Liu, and Jiao Bao Copyright © 2014 Chenxue Yang et al. All rights reserved. Uniform Attractor for the Fractional Nonautonomous Long-Short Wave Equations Mon, 20 Oct 2014 00:00:00 +0000 http://www.hindawi.com/journals/ddns/2014/712183/ We firstly proved the existence and the uniqueness of the solution for the -periodic fractional nonautonomous long-short wave equations with translation compact force by using Galerkin method and then obtained the compact uniform attractor of the system. Huanmin Ge and Jie Xin Copyright © 2014 Huanmin Ge and Jie Xin. All rights reserved.