Discrete Dynamics in Nature and Society http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Rough Set Approach for Group Evacuation Behavior Analysis in Passenger Transport Hub Area Thu, 17 Apr 2014 16:57:52 +0000 http://www.hindawi.com/journals/ddns/2014/682147/ Evacuation behavior analysis is deemed to be one aspect of evacuation planning. However, existing studies have not discussed group evacuation decision-making in the face of disagreement among decision makers. In this paper, rough set theory is applied to analyze group evacuation decision-making in passenger transport hub area with various groups including kin, lover, friend, colleague, and classmate. In the approach, improved tabu search-based attribute reduction is proposed to find the minimal subset of attributes required to fully describe the information of group evacuation decision-making, and value reduction algorithm based on knowledge granulation is used to generate rules of group evacuation decision-making. Cross-validation procedure is adopted to estimate the performance of rough set theory. Experimental results indicate that rough set theory has favorable performance. Thus, the proposed approach provides a new way for evacuation behavior analysis. Peng Chen, Xiaofeng Ma, and Shunying Zhu Copyright © 2014 Peng Chen et al. All rights reserved. Parametrically Excited Oscillations of Second-Order Functional Differential Equations and Application to Duffing Equations with Time Delay Feedback Wed, 16 Apr 2014 06:32:01 +0000 http://www.hindawi.com/journals/ddns/2014/875020/ We study oscillatory behaviour of a large class of second-order functional differential equations with three freedom real nonnegative parameters. According to a new oscillation criterion, we show that if at least one of these three parameters is large enough, then the main equation must be oscillatory. As an application, we study a class of Duffing type quasilinear equations with nonlinear time delayed feedback and their oscillations excited by the control gain parameter or amplitude of forcing term. Finally, some open questions and comments are given for the purpose of further study on this topic. Mervan Pašić Copyright © 2014 Mervan Pašić. All rights reserved. Bifurcations in a Nonlinear Dynamical Model between Western Pacific Subtropical High Ridge Line Index and Its Summer Monsoon Impact Factors Tue, 15 Apr 2014 00:00:00 +0000 http://www.hindawi.com/journals/ddns/2014/709589/ The western Pacific subtropical high (WPSH) is closely related to Asian climate. Previous studies have shown that a precise dynamical model focusing on the interaction between WPSH and other summer monsoon factors has not been developed. Based on the concept of dynamical model reconstruction, this paper reconstructs a nonlinear dynamical model of subtropical high ridge line (SHRL) and summer monsoon factors from recent 20 years data. Then, using genetic algorithm (GA), model inversion and model parameter optimization are carried out. Based on the reconstructed dynamical model, dynamical characteristics of SHRL are analyzed and an aberrance mechanism is developed, in which the external forcings resulting in the WPSH anomalies are explored. Results show that the configuration and diversification of the SHRL equilibriums have better represented the abnormal activities of the SHRL in short and medium term. Change of SHRL brought by the combination of equilibriums is more complex than that brought by mutation. The mutation behavior from high-value to low-value equilibriums of the SHRL in summer corresponds with the southward drop of the SHRL. The combination behavior of the two steady equilibriums corresponds with disappearance of the “double-ridge” phenomenon of WPSH. Dynamical mechanisms of these phenomena are explained. Mei Hong, Ren Zhang, Longxia Qian, Jingjing Ge, and Jian Chen Copyright © 2014 Mei Hong et al. All rights reserved. Pinning Synchronization of One-Sided Lipschitz Complex Networks Sun, 13 Apr 2014 14:46:15 +0000 http://www.hindawi.com/journals/ddns/2014/627060/ This paper studies the pinning synchronization in complex networks with node dynamics satisfying the one-sided Lipschitz condition which is less conservative than the well-known Lipschitz condition. Based on M-matrix theory and Lyapunov functional method, some simple pinning conditions are derived for one-sided Lipschitz complex networks with full-state and partial-state coupling, respectively. A selective pinning scheme is further provided to address the selection of pinned nodes and the design of pinning feedback gains for one-sided Lipschitz complex networks with general topologies. Numerical results are given to illustrate the effectiveness of the theoretical analysis. Fang Liu, Qiang Song, Jinde Cao, and Jianquan Lu Copyright © 2014 Fang Liu et al. All rights reserved. Spectrum of Discrete Second-Order Difference Operator with Sign-Changing Weight and Its Applications Sun, 13 Apr 2014 14:08:39 +0000 http://www.hindawi.com/journals/ddns/2014/590968/ Let be an integer, and let. We discuss the spectrum of discrete linear second-order eigenvalue problems ,  , where is a parameter, changes sign and on . At last, as an application of this spectrum result, we show the existence of sign-changing solutions of discrete nonlinear second-order problems by using bifurcate technique. Ruyun Ma and Chenghua Gao Copyright © 2014 Ruyun Ma and Chenghua Gao. All rights reserved. A Bayesian Network Model for Origin-Destination Matrices Estimation Using Prior and Some Observed Link Flows Sun, 13 Apr 2014 11:19:59 +0000 http://www.hindawi.com/journals/ddns/2014/192470/ This paper presents a Bayesian network model for estimating origin-destination matrices. Most existing Bayesian methods adopt prior OD matrixes, which are always troublesome to be obtained. Since transportation systems normally have stored large amounts of historical link flows, a Bayesian network model using these prior link flows is proposed. Based on some observed link flows, the estimation results are updated. Under normal distribution assumption, the proposed Bayesian network model considers the level of total traffic flow, the variability of link flows, and the violation of the traffic flow conservation law. Both the point estimation and the corresponding probability intervals can be provided by this model. To solve the Bayesian network model, a specific procedure which can avoid matrix inversion is proposed. Finally, a numerical example is given to illustrate the proposed Bayesian network method. The results show that the proposed method has a high accuracy and practical applicability. Lin Cheng, Senlai Zhu, Zhaoming Chu, and Jingxu Cheng Copyright © 2014 Lin Cheng et al. All rights reserved. Cluster Anticonsensus of Multiagent Systems Based on the -Theory Wed, 09 Apr 2014 07:14:43 +0000 http://www.hindawi.com/journals/ddns/2014/254749/ We investigate the problem of cluster anticonsensus of multiagent systems. For multiagent continuous systems, a new control protocol is designed based on the -theory. Then by LaSalle's invariance principle we prove that if the graph is connected and bipartite, then the cluster anticonsensus is achieved by the proposed control protocol. On the other hand, a similar control protocol is designed for multiagent discrete-time systems. Then, sufficient conditions are given to guarantee the cluster anticonsensus of multiagent discrete-time systems by using the -theory and LaSalle's invariance principle. Numerical simulations show the effectiveness of our theoretical results. Liping Zhang, Haibo Jiang, and Shuguang Guo Copyright © 2014 Liping Zhang et al. All rights reserved. Investors’ Risk Preference Characteristics Based on Different Reference Point Wed, 09 Apr 2014 07:11:41 +0000 http://www.hindawi.com/journals/ddns/2014/158386/ Taking the stock market as a whole object, we assume that prior losses and gains are two different factors that can influence risk preference separately. The two factors are introduced as separate explanatory variables into the time-varying GARCH-M (TVRA-GARCH-M) model. Then, we redefine prior losses and gains by selecting different reference point to study investors’ time-varying risk preference. The empirical evidence shows that investors’ risk preference is time varying and is influenced by previous outcomes; the stock market as a whole exhibits house money effect; that is, prior gains can decrease investors’ risk aversion while prior losses increase their risk aversion. Besides, different reference points selected by investors will cause different valuation of prior losses and gains, thus affecting investors’ risk preference. Fenghua Wen, Zhifang He, Xu Gong, and Aiming Liu Copyright © 2014 Fenghua Wen et al. All rights reserved. Multiple Solutions for the Discrete -Laplacian Boundary Value Problems Tue, 08 Apr 2014 09:04:32 +0000 http://www.hindawi.com/journals/ddns/2014/213702/ By employing a critical point theorem, established by Bonanno, we prove the existence of three distinct solutions to boundary value problems of nonlinear difference equations with a discrete p-Laplacian operator. To demonstrate the applicability of our results, we also present an example. Yuhua Long and Haiping Shi Copyright © 2014 Yuhua Long and Haiping Shi. All rights reserved. Further Result on Passivity for Discrete-Time Stochastic T-S Fuzzy Systems with Time-Varying Delays Mon, 07 Apr 2014 13:59:18 +0000 http://www.hindawi.com/journals/ddns/2014/657621/ The passivity for discrete-time stochastic T-S fuzzy systems with time-varying delays is investigated. By constructing appropriate Lyapunov-Krasovskii functionals and employing stochastic analysis method and matrix inequality technique, a delay-dependent criterion to ensure the passivity for the considered T-S fuzzy systems is established in terms of linear matrix inequalities (LMIs) that can be easily checked by using the standard numerical software. An example is given to show the effectiveness of the obtained result. Ting Lei, Qiankun Song, and Zhenjiang Zhao Copyright © 2014 Ting Lei et al. All rights reserved. The Smoothness of Fractal Interpolation Functions on and on -Series Local Fields Mon, 07 Apr 2014 11:23:42 +0000 http://www.hindawi.com/journals/ddns/2014/904576/ A fractal interpolation function on a -series local field is defined, and its -type smoothness is shown by virtue of the equivalent relationship between the Hölder type space and the Lipschitz class Lip. The orders of the -type derivatives and the fractal dimensions of the graphs of Weierstrass type function on local fields are given as an example. The -fractal function on is introduced and the conclusion of its smoothness is improved in a more general case; some examples are shown to support the conclusion. Finally, a comparison between the fractal interpolation functions defined on and is given. Jing Li and Weiyi Su Copyright © 2014 Jing Li and Weiyi Su. All rights reserved. The Normality Criteria of Meromorphic Functions Concerning Shared Fixed-Points Sun, 06 Apr 2014 12:23:30 +0000 http://www.hindawi.com/journals/ddns/2014/654294/ We study the normality criteria of meromorphic functions concerning shared fixed-points; we obtain the following: Let be a family of meromorphic functions defined in a domain and a positive integer. For every , all zeros of are of multiplicity at least and all poles of are multiple. If and share in for each pair of functions and , then is normal. Wei Chen, Qi Yang, Wen-jun Yuan, and Hong-gen Tian Copyright © 2014 Wei Chen et al. All rights reserved. Analytic Continuation of Euler Polynomials and the Euler Zeta Function Thu, 03 Apr 2014 12:20:21 +0000 http://www.hindawi.com/journals/ddns/2014/568129/ We study that the Euler numbers and Euler polynomials are analytically continued to and . We investigate the new concept of dynamics of the zeros of analytica continued polynomials. Finally, we observe an interesting phenomenon of “scattering” of the zeros of . C. S. Ryoo Copyright © 2014 C. S. Ryoo. All rights reserved. Pullback Exponential Attractor for Second Order Nonautonomous Lattice System Thu, 03 Apr 2014 12:05:46 +0000 http://www.hindawi.com/journals/ddns/2014/237027/ We first present some sufficient conditions for the existence of a pullback exponential attractor for continuous process on the product space of the weighted spaces of infinite sequences. Then we prove the existence and continuity of a pullback exponential attractor for second order lattice system with time-dependent coupled coefficients in the weighted space of infinite sequences. Moreover, we obtain the upper bound of fractal dimension and attracting rate for the attractor. Shengfan Zhou, Hong Chen, and Zhaojuan Wang Copyright © 2014 Shengfan Zhou et al. All rights reserved. Stability Analysis for Fractional-Order Linear Singular Delay Differential Systems Thu, 03 Apr 2014 07:51:22 +0000 http://www.hindawi.com/journals/ddns/2014/850279/ We investigate the delay-independently asymptotic stability of fractional-order linear singular delay differential systems. Based on the algebraic approach, the sufficient conditions are presented to ensure the asymptotic stability for any delay parameter. By applying the stability criteria, one can avoid solving the roots of transcendental equations. An example is also provided to illustrate the effectiveness and applicability of the theoretical results. Hai Zhang, Daiyong Wu, Jinde Cao, and Hui Zhang Copyright © 2014 Hai Zhang et al. All rights reserved. A Conceptual Architecture for Adaptive Human-Computer Interface of a PT Operation Platform Based on Context-Awareness Thu, 03 Apr 2014 07:15:35 +0000 http://www.hindawi.com/journals/ddns/2014/371204/ We present a conceptual architecture for adaptive human-computer interface of a PT operation platform based on context-awareness. This architecture will form the basis of design for such an interface. This paper describes components, key technologies, and working principles of the architecture. The critical contents covered context information modeling, processing, relationship establishing between contexts and interface design knowledge by use of adaptive knowledge reasoning, and visualization implementing of adaptive interface with the aid of interface tools technology. Qing Xue, Xuan Han, Mingrui Li, and Minxia Liu Copyright © 2014 Qing Xue et al. All rights reserved. Note on the Stability Property of a Cooperative System Incorporating Harvesting Wed, 02 Apr 2014 14:36:04 +0000 http://www.hindawi.com/journals/ddns/2014/327823/ The stability of a kind of cooperative model incorporating harvesting is revisited in this paper. By using an iterative method, the global attractivity of the interior equilibrium point of the system is investigated. We show that the condition which ensures the existence of a unique positive equilibrium is enough to ensure the global attractivity of the positive equilibrium. Our results significantly improve the corresponding results of Wei and Li (2013). Xiangdong Xie, Fengde Chen, and Yalong Xue Copyright © 2014 Xiangdong Xie et al. All rights reserved. Synchronization of Fractional-Order Hyperchaotic Systems via Fractional-Order Controllers Tue, 01 Apr 2014 07:51:25 +0000 http://www.hindawi.com/journals/ddns/2014/408972/ In this paper, the synchronization of fractional-order chaotic systems is studied and a new fractional-order controller for hyperchaos synchronization is presented based on the Lyapunov stability theory. The proposed synchronized method can be applied to an arbitrary four-dimensional fractional hyperchaotic system. And we give the optimal value of control parameters to achieve synchronization of fractional hyperchaotic system. This approach is universal, simple, and theoretically rigorous. Numerical simulations of several fractional-order hyperchaotic systems demonstrate the universality and the effectiveness of the proposed method. Tianzeng Li, Yu Wang, and Yong Yang Copyright © 2014 Tianzeng Li et al. All rights reserved. A Nonparametric Operational Risk Modeling Approach Based on Cornish-Fisher Expansion Mon, 31 Mar 2014 13:52:18 +0000 http://www.hindawi.com/journals/ddns/2014/839731/ It is generally accepted that the choice of severity distribution in loss distribution approach has a significant effect on the operational risk capital estimation. However, the usually used parametric approaches with predefined distribution assumption might be not able to fit the severity distribution accurately. The objective of this paper is to propose a nonparametric operational risk modeling approach based on Cornish-Fisher expansion. In this approach, the samples of severity are generated by Cornish-Fisher expansion and then used in the Monte Carlo simulation to sketch the annual operational loss distribution. In the experiment, the proposed approach is employed to calculate the operational risk capital charge for the overall Chinese banking. The experiment dataset is the most comprehensive operational risk dataset in China as far as we know. The results show that the proposed approach is able to use the information of high order moments and might be more effective and stable than the usually used parametric approach. Xiaoqian Zhu, Jianping Li, Jianming Chen, Yingqi YangHuo, Lijun Gao, Jichuang Feng, Dengsheng Wu, and Yongjia Xie Copyright © 2014 Xiaoqian Zhu et al. All rights reserved. Modeling and Application of Pedestrian Safety Conflict Index at Signalized Intersections Mon, 31 Mar 2014 12:21:44 +0000 http://www.hindawi.com/journals/ddns/2014/314207/ Traffic conflict between turning vehicles and pedestrians is the leading cause of pedestrian fatalities at signalized intersections. In order to provide a solution for evaluating intersection safety for vulnerable road users, this paper first determines the most important factors in analyzing pedestrian-vehicle conflict and puts forward a pedestrian safety conflict index (SCI) model to establish a quantitative standard for safety evaluation of two- or multiphase intersections. A safety level system is then designed based on SCI to help categorize and describe the safety condition of intersections applicable to the model. Finally, the SCI model is applied to the evaluation of two intersections in the city of Changchun, the result of which complies with expectation, indicating the model’s potential in providing an improved approach for pedestrian-vehicle conflict evaluation study. Wei Cheng, Ning Zhang, Wei Li, and Jianfeng Xi Copyright © 2014 Wei Cheng et al. All rights reserved. The Evolution of the Strategies of Innovation Cooperation in Scale-Free Network Mon, 31 Mar 2014 11:56:10 +0000 http://www.hindawi.com/journals/ddns/2014/805373/ One of the important research works is corporate partnering and reliance on various forms of external collaboration. Although many researchers have focused on the knowledge-based work to help firms collaborate and share their knowledge, few have comprehensively considered the structure of network and cooperative strategies. Our paper differentiates three situations of innovation, and simulates the actions of cooperation between firms with different life cycles in industry cluster with the scale-free network structure. The simulation results show that (a) when the industry cluster develops, firms’ absorbability also is growing, but the behaviors of cooperation do not always increase as firms’ absorbability grows. Sometimes they exhibit inverted U-shape, U-shape, or liner trend. (b) Firms will cooperate to share their information or knowledge automatically if the payoff of the innovation is bigger. (c) The incentive policy does encourage the cooperation between the firms, but the incentive policy about compensation with each cooperation action is more effective than with the periodic fixed incentive. Bing Zhu and Wenping Wang Copyright © 2014 Bing Zhu and Wenping Wang. All rights reserved. Chaos and Hopf Bifurcation Analysis of the Delayed Local Lengyel-Epstein System Sun, 30 Mar 2014 15:52:54 +0000 http://www.hindawi.com/journals/ddns/2014/139375/ The local reaction-diffusion Lengyel-Epstein system with delay is investigated. By choosing as bifurcating parameter, we show that Hopf bifurcations occur when time delay crosses a critical value. Moreover, we derive the equation describing the flow on the center manifold; then we give the formula for determining the direction of the Hopf bifurcation and the stability of bifurcating periodic solutions. Finally, numerical simulations are performed to support the analytical results and the chaotic behaviors are observed. Qingsong Liu, Yiping Lin, Jingnan Cao, and Jinde Cao Copyright © 2014 Qingsong Liu et al. All rights reserved. Joint Optimal Pricing and Ordering Decisions for Seasonal Products with Weather-Sensitive Demand Thu, 27 Mar 2014 12:39:18 +0000 http://www.hindawi.com/journals/ddns/2014/105098/ Retailers selling seasonal products often face the challenge in matching their inventory levels with uncertain market demand which is sensitive to weather conditions, such as the average seasonal temperature. Therefore, how to make the joint ordering and pricing decisions may help retailers to increase their profits. In this paper, we address the joint determination of pricing and ordering decisions in a newsvendor setting, where a retailer (newsvendor) sells the seasonal products and faces demand risk due to weather uncertainty. We show that the maximum expected profit function is continuous and concave, so the optimal solution to the retail price and order quantity exists and it is the one and only solution. In addition, we numerically investigate the impacts of related parameters on the retailer’s expected profit and the optimal pricing and ordering decisions and illustrate some useful management insights into the economic behavior of firms. Hongyong Fu, Bin Dan, and Xiangkai Sun Copyright © 2014 Hongyong Fu et al. All rights reserved. The Effect of Impulsive Vaccination on Delayed SEIRS Epidemic Model Incorporating Saturation Recovery Tue, 25 Mar 2014 12:21:30 +0000 http://www.hindawi.com/journals/ddns/2014/426456/ A delay SEIRS model with pulse vaccination incorporating a general media coverage function and saturation recovery is investigated. Using the discrete dynamical system determined by the stroboscopic map, we obtain the existence of the disease-free periodic solution and its exact expression. Further, using the comparison theorem, we establish the sufficient conditions of global attractivity of the disease-free periodic solution. Moreover, we show that the disease is uniformly persistent if vaccination rate is less than . Finally, we discuss the effect of media coverage on controlling disease. Yongfeng Li, Dongliang Xie, and Jing-an Cui Copyright © 2014 Yongfeng Li et al. All rights reserved. Equilibrium Customer Strategies in the Geo/Geo/1 Queue with Single Working Vacation Sun, 23 Mar 2014 12:58:33 +0000 http://www.hindawi.com/journals/ddns/2014/309489/ This paper is concerned with the equilibrium balking strategies of customers in a Geo/Geo/1 queue with single working vacation. Instead of completely stopping service, the server works with a small probability during the working vacation period. As soon as no customers exist in the system, the server takes a single vacation. The customers decide for themselves whether to enter the system or balk based on a natural reward-cost structure, the information available about the status of the server, and the queue length on hand upon arrival. We obtain the equilibrium balking strategies in two cases: fully observable and fully unobservable cases, which depend on whether the customers know both the queue length and the state of the server or none of them. Finally, we present several numerical experiments that demonstrate the effect of some parameters on the equilibrium behavior. Fang Wang, Jinting Wang, and Feng Zhang Copyright © 2014 Fang Wang et al. All rights reserved. Smolyak-Grid-Based Flutter Analysis with the Stochastic Aerodynamic Uncertainty Sun, 23 Mar 2014 11:31:05 +0000 http://www.hindawi.com/journals/ddns/2014/174927/ How to estimate the stochastic aerodynamic parametric uncertainty on aeroelastic stability is studied in this current work. The aerodynamic uncertainty is more complicated than the structural one, and it takes more significant effect on the flutter boundary. First, the nominal unsteady aerodynamic influence coefficients were calculated with the doublet lattice method. Based on this nominal model, the stochastic uncertainty model for unsteady aerodynamic pressure coefficients was constructed with physical meaning. Afterwards, the methodology for flutter uncertainty quantification due to aerodynamic perturbation was developed, based on the nonintrusive polynomial chaos expansion theory. In order to enhance the computational efficiency, the integration algorithm, namely, Smolyak sparse grids, was employed to calculate the coefficients of the stochastic polynomial basis. Finally, the flutter uncertainty analysis methodology was applied to an aircraft's wing model. The influence of uncertainty with uniform distribution for aerodynamic pressure coefficients on flutter boundary was quantified. The numerical results indicate that, the influence of unsteady aerodynamic pressure due to the motion of coupling modes takes significant effect on flutter boundary. It is validated that the flutter uncertainty analysis based on Smolyak sparse grids integration is efficient and accurate for quantifying input uncertainty with high dimensions. Yuting Dai and Chao Yang Copyright © 2014 Yuting Dai and Chao Yang. All rights reserved. Finite-Time Stability and Stabilization of Networked Control Systems with Bounded Markovian Packet Dropout Sun, 23 Mar 2014 07:47:02 +0000 http://www.hindawi.com/journals/ddns/2014/176919/ The finite-time stability and stabilization problems of a class of networked control systems (NCSs) with bounded Markovian packet dropout are investigated. The main results provided in the paper are sufficient conditions for finite-time stability and stabilization via state feedback. An iterative approach is proposed to model NCSs with bounded packet dropout as jump linear systems (JLSs). Based on Lyapunov stability theory and JLSs theory, the sufficient conditions for finite-time stability and stabilization of the underlying systems are derived via linear matrix inequalities (LMIs) formulation. Lastly, an illustrative example is given to demonstrate the effectiveness of the proposed results. Yeguo Sun and Guanjun Li Copyright © 2014 Yeguo Sun and Guanjun Li. All rights reserved. Chaotic Characteristics and Application of Cooperative Game and Evolutionary Game Wed, 19 Mar 2014 09:26:55 +0000 http://www.hindawi.com/journals/ddns/2014/908093/ According to a dynamical multiteam Cournot game in exploitation of a renewable resource, a new dynamic Cournot duopoly game model with team players in exploitation of a renewable resource is built up in this paper. Based on the theory of bifurcations of dynamical systems, the stability of the system is studied and the local stable region of Nash equilibrium point is obtained. The effect of the output adjustment speed parameters and the weight parameter of the system on the dynamic characteristics of the system are researched. The complexity of the system is described via the bifurcation diagrams, the Lyapunov exponents, the phase portrait, the time history diagram, and the fractal dimension. Furthermore, the chaos control of the system is realized by the parameter adjustment method. At last, an evolutionary game as a special dynamic system is constructed and analyzed which is more useful and helpful in application. The derived results have very important theoretical and practical values for the renewable resource market and companies. Yujing Yang, Junhai Ma, and Hongliang Tu Copyright © 2014 Yujing Yang et al. All rights reserved. On the Steady-State System Size Distribution for a Discrete-Time Geo/G/1 Repairable Queue Wed, 19 Mar 2014 08:38:19 +0000 http://www.hindawi.com/journals/ddns/2014/924712/ This paper studies a discrete-time N-policy Geo/G/1 queueing system with feedback and repairable server. With a probabilistic analysis method and renewal process theory, the steady-state system size distribution is derived. Further, the steady-state system size distribution derived in this work is extremely suitable for numerical calculations. Numerical example illustrates the important application of steady-state system size distribution in system capacity design for a network access proxy system. Renbin Liu and Zhaohui Deng Copyright © 2014 Renbin Liu and Zhaohui Deng. All rights reserved. An Innovative Architecture of UTC GPS/INS System with Improved Performance under Severe Jamming Wed, 19 Mar 2014 07:43:28 +0000 http://www.hindawi.com/journals/ddns/2014/185618/ Ultratightly coupled (UTC) architecture is believed to be the best architecture for Global Positioning System (GPS) and Inertial Navigation System (INS) integration system due to the advanced data fusion strategy and effective mutual assistance between the subsystems. However the performance of UTC GPS/INS system will be degraded by severe jamming interference, especially when low-grade inertial measurement unit (IMU) is used. To solve this problem an innovative architecture of UTC GPS/INS system is proposed. Since GPS receiver’s antijamming ability is closely related to tracking loop bandwidth, adaptive tracking loop bandwidth based on the fuzzy logics is proposed to enhance antijamming ability for GPS receiver. The bandwidth will be adapted through a fuzzy logic controller according to the calculated carrier to noise intensity ratio . Moreover, fuzzy adaptive integration Kalman filter (IKF) is developed to improve estimation accuracy of IKF when measurement noises change. A simulation platform is established to evaluate the innovative architecture and results demonstrate that the proposed scheme improves navigation performance significantly under severe jamming conditions. Xueyun Wang, Jingjuan Zhang, Wei Wang, and Pengyu Gao Copyright © 2014 Xueyun Wang et al. All rights reserved.