Discrete Dynamics in Nature and Society http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Hierarchical Artificial Bee Colony Optimizer with Divide-and-Conquer and Crossover for Multilevel Threshold Image Segmentation Tue, 02 Sep 2014 13:23:49 +0000 http://www.hindawi.com/journals/ddns/2014/941534/ This paper presents a novel optimization algorithm, namely, hierarchical artificial bee colony optimization (HABC), for multilevel threshold image segmentation, which employs a pool of optimal foraging strategies to extend the classical artificial bee colony framework to a cooperative and hierarchical fashion. In the proposed hierarchical model, the higher-level species incorporates the enhanced information exchange mechanism based on crossover operator to enhance the global search ability between species. In the bottom level, with the divide-and-conquer approach, each subpopulation runs the original ABC method in parallel to part-dimensional optimum, which can be aggregated into a complete solution for the upper level. The experimental results for comparing HABC with several successful EA and SI algorithms on a set of benchmarks demonstrated the effectiveness of the proposed algorithm. Furthermore, we applied the HABC to the multilevel image segmentation problem. Experimental results of the new algorithm on a variety of images demonstrated the performance superiority of the proposed algorithm. Maowei He, Kunyuan Hu, Yunlong Zhu, Lianbo Ma, Hanning Chen, and Yan Song Copyright © 2014 Maowei He et al. All rights reserved. Set of Oscillation Criteria for Second Order Nonlinear Forced Differential Equations with Damping Tue, 02 Sep 2014 12:29:51 +0000 http://www.hindawi.com/journals/ddns/2014/545189/ By employing a generalized Riccati technique and an integral averaging technique, some new oscillation criteria are established for the second order nonlinear forced differential equation with damping. These results extend, improve, and unify some known oscillation criteria in the existing literature. Ambarka Abdalla Salhin, Ummul Khair Salma Din, Rokiah Rozita Ahmad, and Mohd Salmi Md Noorani Copyright © 2014 Ambarka Abdalla Salhin et al. All rights reserved. How Do Sociodemographics and Activity Participations Affect Activity-Travel? Comparative Study between Women and Men Tue, 02 Sep 2014 12:18:11 +0000 http://www.hindawi.com/journals/ddns/2014/374521/ Activity-travel behaviors of women and men are different because they have different social and household responsibilities. However, studies concerning gender differences are mainly limited in developed countries. This paper concentrates on gender role-based differences in activity-travel behavior in a typical developing country, namely, China. Using data from 3656 cases collected through surveys conducted in Shangyu, data processing, method choice, and descriptive analysis were conducted. Binary and ordered logistic regression models segmented by gender were developed to evaluate the mechanism through which individual sociodemographics, household characteristics, and activity participations affect the number of trip chain types and activities for women and men. The results show that women aged 30 to 50 perform less subsistence activities. However, the difference between the different age groups of men is not as significant. In addition, men with bicycles and electric bicycles have more subsistence and maintenance activities, whereas women do not have these attributes. Moreover, women with children under schooling age make more maintenance trip chains but less leisure trip chains and activities, whereas men are free from this influence. Furthermore, both women and men perform more subsistence activities if the duration increases, and men have less influences than women do. Min Yang, Wei Wang, Feifei Yu, and Jian Ding Copyright © 2014 Min Yang et al. All rights reserved. Global Dynamics of Infectious Disease with Arbitrary Distributed Infectious Period on Complex Networks Mon, 01 Sep 2014 12:49:21 +0000 http://www.hindawi.com/journals/ddns/2014/161509/ Most of the current epidemic models assume that the infectious period follows an exponential distribution. However, due to individual heterogeneity and epidemic diversity, these models fail to describe the distribution of infectious periods precisely. We establish a SIS epidemic model with multistaged progression of infectious periods on complex networks, which can be used to characterize arbitrary distributions of infectious periods of the individuals. By using mathematical analysis, the basic reproduction number for the model is derived. We verify that the depends on the average distributions of infection periods for different types of infective individuals, which extend the general theory obtained from the single infectious period epidemic models. It is proved that if , then the disease-free equilibrium is globally asymptotically stable; otherwise the unique endemic equilibrium exists such that it is globally asymptotically attractive. Finally numerical simulations hold for the validity of our theoretical results is given. Xiaoguang Zhang, Rui Song, Gui-Quan Sun, and Zhen Jin Copyright © 2014 Xiaoguang Zhang et al. All rights reserved. An Immunization Strategy Based on Propagation Mechanism Mon, 01 Sep 2014 11:45:02 +0000 http://www.hindawi.com/journals/ddns/2014/971497/ With the ubiquity of smart phones, wearable equipment, and wireless sensors, the topologies of networks composed by them change along with time. The immunization strategies in which network immune nodes are chosen by analyzing the static aggregation network topologies have been challenged. The studies about interaction propagations between two pathogens show that the interaction can change propagation threshold and the final epidemic size of each other, which provides a new thinking of immunization method. The eradication or inhibition of the virus can be achieved through the spread of its opposite party. Here, we put forward an immunization strategy whose implementation does not depend on the analysis of network topology. The immunization agents are randomly placed on a few of individuals of network and spread out from these individuals on network in a propagation method. The immunization agents prevent virus infecting their habitat nodes with certain immune success rate. The analysis and simulation of evolution equation of the model show that immune propagation has a significant impact on the spread threshold and steady-state density of virus on a finite size of BA networks. Simulations on some real-world networks also suggest that the immunization strategy is feasible and effective. Yixin Zhu, Fengli Zhang, and Wenqiang Guo Copyright © 2014 Yixin Zhu et al. All rights reserved. Allocating Freight Empty Cars in Railway Networks with Dynamic Demands Mon, 01 Sep 2014 07:29:41 +0000 http://www.hindawi.com/journals/ddns/2014/349341/ This paper investigates the freight empty cars allocation problem in railway networks with dynamic demands, in which the storage cost, unit transportation cost, and demand in each stage are taken into consideration. Under the constraints of capacity and demand, a stage-based optimization model for allocating freight empty cars in railway networks is formulated. The objective of this model is to minimize the total cost incurred by transferring and storing empty cars in different stages. Moreover, a genetic algorithm is designed to obtain the optimal empty cars distribution strategies in railway networks. Finally, numerical experiments are given to show the effectiveness of the proposed model and algorithm. Ce Zhao, Lixing Yang, and Shukai Li Copyright © 2014 Ce Zhao et al. All rights reserved. Optimal Road Toll Design from the Perspective of Sustainable Development Mon, 01 Sep 2014 00:00:00 +0000 http://www.hindawi.com/journals/ddns/2014/548427/ This paper investigates the optimal road toll design problem from the perspective of sustainable development at network-wide level. In this paper the sustainable development level of transportation system is quantitatively described with the total vehicular emission, total fuel consumption, and total travel time in the network. In order to simultaneously consider the impacts of all these three indicators on sustainability of transportation system, we integrate them into a sustainable development index (SD-index) by a linear combination, and then we establish the corresponding bilevel optimization model. The upper level problem is the network toll design problem to maximize the SD-index from the viewpoint of traffic managers, and the lower level problem is to depict travelers’ route choice behavior under a certain road toll scheme. Finally, a combined genetic algorithm and gradient projection algorithm (GA-GP) is used to solve the bilevel model, in which the GP algorithm solves the traffic assignment problem with road toll scheme in the lower level. In order to verify the proposed model and algorithm, we take the Nguyen-Dupuis network for the numerical example, and the computing results show that the model and algorithm are effective and efficient. Lin Cheng and Fei Han Copyright © 2014 Lin Cheng and Fei Han. All rights reserved. The Role of Constraints in a Segregation Model: The Asymmetric Case Sun, 31 Aug 2014 07:50:52 +0000 http://www.hindawi.com/journals/ddns/2014/569296/ We extend the analysis on the effects of the entry constraints on the dynamics of an adaptive segregation model of Shelling’s type when the two populations involved differ in numerosity, level of tolerance toward members of the other population, and speed of reaction. The model is described by a two-dimensional piecewise smooth dynamical system in discrete time, where the entry constraints represent possible exogenous controls imposed by an authority in order to regulate the maximum number of members of the two populations allowed to enter the system, usually the district in which they live in. In this paper, we investigate the nature of some particular border collision bifurcations and discuss the policy implications of the entry constraints in terms of segregation. The investigation reveals that asymmetries in the level of tolerance of the two populations involved may lead to phenomena of overreaction or overshooting in the adjustment process. In order to avoid the risk of segregation, suitable entry limitations must be imposed at least on the more tolerant population. Davide Radi, Laura Gardini, and Viktor Avrutin Copyright © 2014 Davide Radi et al. All rights reserved. Fare Optimality Analysis of Urban Rail Transit under Various Objective Functions Thu, 28 Aug 2014 00:00:00 +0000 http://www.hindawi.com/journals/ddns/2014/910736/ Urban rail transit fare strategies include fare structures and fare levels. We propose a rail transit line fare decision based on an operating plan that falls under elastic demand. Combined with the train operation plan, considering flat fare and distance-based fare, and based on the benefit analysis of both passenger flow and operating enterprises, we construct the objective functions and build an optimization model in terms of the operators’ interests, the system’s efficiency, system regulation goals, and the system costs. The solving algorithm based on the simulated annealing algorithm is established. Using as an example the Changsha Metro Line 2, we analyzed the optimized results of different models under the two fare structures system. Finally the recommendations of fare strategies are given. Lianbo Deng, Zhao Zhang, Kangni Liu, Wenliang Zhou, and Junfeng Ma Copyright © 2014 Lianbo Deng et al. All rights reserved. A Unified Weight Formula for Calculating the Sample Variance from Weighted Successive Differences Wed, 27 Aug 2014 15:20:07 +0000 http://www.hindawi.com/journals/ddns/2014/210761/ The basic formula to calculate sample variance is based on the sum of squared differences from mean. From computational perspective, mean calculation is nondesired as it can introduce computing errors. Previous researches have proposed to use weighted formula of the successive differences to calculate sample variance to avoid mean calculation. But their weighted formula is not in a unified format in the sense that it has to be represented as two formulas. This paper proposes a unified weight formula for sample variance calculation from weighted successive differences. A proof is provided to show that sample variance calculated using the proposed unified weighted formula is mathematically equivalent to the basic definition. Kuo-Hung Lo, Tien-Lung Sun, and Juei-Chao Chen Copyright © 2014 Kuo-Hung Lo et al. All rights reserved. An Improved Algorithm in Porosity Characteristics Analysis for Rock and Soil Aggregate Wed, 27 Aug 2014 08:14:06 +0000 http://www.hindawi.com/journals/ddns/2014/798235/ The rock and soil aggregate (RSA) is a special inhomogeneous multiphase geomaterial. It is crucial for stability of engineering by study of RSA mesodamage characteristic. This paper aims at investigating the porosity evolution characteristics of RSA by X-ray computed tomography (CT) under uniaxial compressive loading. X-ray tomography images were used to extract defects of RSA specimen under different compressive loading. In this paper, we proposed an improved Ostu method to calibrate the beam hardening phenomenon which is caused by X-ray. Also, based on this Ostu method, the outline of rock blocks in RSA is extracted, and the double gray level threshold of soil and rock block is obtained to ensure the reliability of the porosity calculation. We can conclude that the main reason of RSA cracking is the elasticity mismatch between rock blocks and soil, and the porosity evolution of RSA can be divided into four typical stages. These results may be useful to reveal the mesoscopic cracking mechanism and establish mesodamage evolution equation and constitutive relation for RSA. Yanfang Wu, Xiao Li, Yu Wang, and Bo Zhang Copyright © 2014 Yanfang Wu et al. All rights reserved. Particle Swarm Optimization Based on Local Attractors of Ordinary Differential Equation System Tue, 26 Aug 2014 07:22:29 +0000 http://www.hindawi.com/journals/ddns/2014/628357/ Particle swarm optimization (PSO) is inspired by sociological behavior. In this paper, we interpret PSO as a finite difference scheme for solving a system of stochastic ordinary differential equations (SODE). In this framework, the position points of the swarm converge to an equilibrium point of the SODE and the local attractors, which are easily defined by the present position points, also converge to the global attractor. Inspired by this observation, we propose a class of modified PSO iteration methods (MPSO) based on local attractors of the SODE. The idea of MPSO is to choose the next update state near the present local attractor, rather than the present position point as in the original PSO, according to a given probability density function. In particular, the quantum-behaved particle swarm optimization method turns out to be a special case of MPSO by taking a special probability density function. The MPSO methods with six different probability density functions are tested on a few benchmark problems. These MPSO methods behave differently for different problems. Thus, our framework not only gives an interpretation for the ordinary PSO but also, more importantly, provides a warehouse of PSO-like methods to choose from for solving different practical problems. Wenyu Yang, Wei Wu, Yetian Fan, and Zhengxue Li Copyright © 2014 Wenyu Yang et al. All rights reserved. On Ulam’s Type Stability of the Linear Equation and Related Issues Mon, 25 Aug 2014 07:25:10 +0000 http://www.hindawi.com/journals/ddns/2014/536791/ This is a survey paper concerning stability results for the linear functional equation in single variable. We discuss issues that have not been considered or have been treated only briefly in other surveys concerning stability of the equation. In this way, we complement those surveys. Janusz Brzdęk, Krzysztof Ciepliński, and Zbigniew Leśniak Copyright © 2014 Janusz Brzdęk et al. All rights reserved. Macroscopic Model and Simulation Analysis of Air Traffic Flow in Airport Terminal Area Mon, 25 Aug 2014 05:36:40 +0000 http://www.hindawi.com/journals/ddns/2014/741654/ We focus on the spatiotemporal characteristics and their evolvement law of the air traffic flow in airport terminal area to provide scientific basis for optimizing flight control processes and alleviating severe air traffic conditions. Methods in this work combine mathematical derivation and simulation analysis. Based on cell transmission model the macroscopic models of arrival and departure air traffic flow in terminal area are established. Meanwhile, the interrelationship and influential factors of the three characteristic parameters as traffic flux, density, and velocity are presented. Then according to such models, the macro emergence of traffic flow evolution is emulated with the NetLogo simulation platform, and the correlativity of basic traffic flow parameters is deduced and verified by means of sensitivity analysis. The results suggest that there are remarkable relations among the three characteristic parameters of the air traffic flow in terminal area. Moreover, such relationships evolve distinctly with the flight procedures, control separations, and ATC strategies. Honghai Zhang, Yan Xu, Lei Yang, and Hao Liu Copyright © 2014 Honghai Zhang et al. All rights reserved. Intuitionistic Fuzzy Planar Graphs Sun, 24 Aug 2014 05:44:48 +0000 http://www.hindawi.com/journals/ddns/2014/397823/ Graph theory has numerous applications in modern sciences and technology. Atanassov introduced the concept of intuitionistic fuzzy sets as a generalization of fuzzy sets. Intuitionistic fuzzy set has shown advantages in handling vagueness and uncertainty compared to fuzzy set. In this paper, we apply the concept of intuitionistic fuzzy sets to multigraphs, planar graphs, and dual graphs. We introduce the notions of intuitionistic fuzzy multigraphs, intuitionistic fuzzy planar graphs, and intuitionistic fuzzy dual graphs and investigate some of their interesting properties. We also study isomorphism between intuitionistic fuzzy planar graphs. Noura Alshehri and Muhammad Akram Copyright © 2014 Noura Alshehri and Muhammad Akram. All rights reserved. A Note on the Rate of Strong Convergence for Weighted Sums of Arrays of Rowwise Negatively Orthant Dependent Random Variables Wed, 20 Aug 2014 06:38:01 +0000 http://www.hindawi.com/journals/ddns/2014/368702/ Let be an array of rowwise negatively orthant dependent (NOD) random variables. The authors discuss the rate of strong convergence for weighted sums of arrays of rowwise NOD random variables and solve an open problem posed by Huang and Wang (2012). Qingxia Zhang and Dingcheng Wang Copyright © 2014 Qingxia Zhang and Dingcheng Wang. All rights reserved. Heterogeneous Fundamentalists in a Continuous Time Model with Delays Wed, 20 Aug 2014 00:00:00 +0000 http://www.hindawi.com/journals/ddns/2014/959514/ We develop a continuous time model with heterogeneous fundamentalists, imitators, and discrete time delays. We show that nonlinear dynamic phenomena, such as coexistence of attractors and local and global bifurcations, occur due to the existence of a time gap in the process of adjustment of market prices. Luca Gori, Luca Guerrini, and Mauro Sodini Copyright © 2014 Luca Gori et al. All rights reserved. Multiple-Decision Procedures for Testing the Homogeneity of Mean for Exponential Distributions Tue, 19 Aug 2014 09:04:27 +0000 http://www.hindawi.com/journals/ddns/2014/701074/ In multiple-decision procedures, a crucial objective is to determine the association between the probability of a correct decision (CD) and the sample size. A review of some methods is provided, including a subset selection formulation proposed by Huang and Panchapakesan, a multidecision procedure for testing the homogeneity of means by Huang and Lin, and a similar procedure for testing the homogeneity of variances by Lin and Huang. In this paper, we focus on the use of the Lin and Huang method for testing the null hypothesis of homogeneity of means for exponential distributions. We discuss the decision rule , evaluation of the critical value , and the infimum of for independent random samples from exponential distributions. In addition, we also observed that a lower bound for the probability of CD relative to the number of the common sample size is determined based on the desired probability of CD when the largest mean is sufficiently larger than the other means. We explain the results by using two examples. Han-Ching Chen, Her Pei Shan, and Nae-Sheng Wang Copyright © 2014 Han-Ching Chen et al. All rights reserved. Monotone Iterative Technique and Symmetric Positive Solutions to Fourth-Order Boundary Value Problem with Integral Boundary Conditions Mon, 18 Aug 2014 12:06:27 +0000 http://www.hindawi.com/journals/ddns/2014/583875/ The purpose of this paper is to investigate the existence of symmetric positive solutions for a class of fourth-order boundary value problem: , , , , where , . By using a monotone iterative technique, we prove that the above boundary value problem has symmetric positive solutions under certain conditions. In particular, these solutions are obtained via the iteration procedures. Huihui Pang and Chen Cai Copyright © 2014 Huihui Pang and Chen Cai. All rights reserved. Rumor-Propagation Model with Consideration of Refutation Mechanism in Homogeneous Social Networks Mon, 18 Aug 2014 08:55:55 +0000 http://www.hindawi.com/journals/ddns/2014/659273/ In recent years, increasing attention has been paid to how to effectively manage rumor propagation. Based on previous studies of rumor propagation and some strategies used by the authorities to refute rumors and manage rumor propagation, we develop a new rumor-propagation model with consideration of refutation mechanism. In this paper, we describe the dynamic process of rumor propagation by accounting for the refutation mechanism in homogeneous social networks. And then, we derive mean-field equations for rumor-propagation process. We then analyze the stability of the model with respect to changes in parameter values. Our results show that there exists a critical threshold that is inversely proportional to the average degree of the social networks and is positively correlated with the strength of the refutation mechanism. If the spreading rate is bigger than the critical threshold , rumors can be spread. Our numerical simulations in homogeneous networks demonstrate that increasing the ignorant’s refutation rate can reduce the peak value of spreaders density, which is better than increasing the spreader’s refutation rate . Therefore, based on the seriousness of the rumor propagation and the rumor-propagation rate, the authorities can choose effective strategies that increase the refutation rate so that they can reduce the maximum influence of the rumor. Laijun Zhao, Xiaoli Wang, Jiajia Wang, Xiaoyan Qiu, and Wanlin Xie Copyright © 2014 Laijun Zhao et al. All rights reserved. Positive Switched System Approach to Traffic Signal Control for Oversaturated Intersection Sun, 17 Aug 2014 11:04:44 +0000 http://www.hindawi.com/journals/ddns/2014/381567/ The online traffic signalization for intersection is addressed. A new model for intersection called positive switched system is presented. Then, based on the dissipativity analysis results for positive switched system, an online state-feedback control strategy for traffic signal in two-phase intersection section is proposed. A numerical example is provided to illustrate the effectiveness of our theoretical findings. Finally, in order to extend to more general cases, multiphase intersection is considered, and general dissipativity-based control is presented. Lin Du and Yun Zhang Copyright © 2014 Lin Du and Yun Zhang. All rights reserved. Existence of Positive Periodic Solutions for -Dimensional Nonautonomous System Sun, 17 Aug 2014 08:07:10 +0000 http://www.hindawi.com/journals/ddns/2014/268418/ In this paper we consider the existence, multiplicity, and nonexistence of positive periodic solutions for n-dimensional nonautonomous functional differential system , where are -periodic in and there exist -periodic functions such that for all with and , exist for ; are -periodic functions and , for ; is an -periodic function. We show that the system has multiple or no positive -periodic solutions for sufficiently large or small , respectively. Youjun Liu, Huanhuan Zhao, and Jurang Yan Copyright © 2014 Youjun Liu et al. All rights reserved. Fractional Order Stochastic Differential Equation with Application in European Option Pricing Wed, 13 Aug 2014 07:03:29 +0000 http://www.hindawi.com/journals/ddns/2014/621895/ Memory effect is an important phenomenon in financial systems, and a number of research works have been carried out to study the long memory in the financial markets. In recent years, fractional order ordinary differential equation is used as an effective instrument for describing the memory effect in complex systems. In this paper, we establish a fractional order stochastic differential equation (FSDE) model to describe the effect of trend memory in financial pricing. We, then, derive a European option pricing formula based on the FSDE model and prove the existence of the trend memory (i.e., the mean value function) in the option pricing formula when the Hurst index is between 0.5 and 1. In addition, we make a comparison analysis between our proposed model, the classic Black-Scholes model, and the stochastic model with fractional Brownian motion. Numerical results suggest that our model leads to more accurate and lower standard deviation in the empirical study. Qing Li, Yanli Zhou, Xinquan Zhao, and Xiangyu Ge Copyright © 2014 Qing Li et al. All rights reserved. Ananlysis of Carbon Emission Reduction and Power Dominance between Single Manufacturer and Single Retailer in Regulatory Cap and Trade System Mon, 11 Aug 2014 11:39:40 +0000 http://www.hindawi.com/journals/ddns/2014/523451/ In the cap and trade system, the paper analyses the Stackelberg game between the power asymmetrical retailer and manufacturer and designs a side-payment self-enforcing contract to resolve some arguments that the existing research overemphasizes spontaneity of participation in side-payment contracts design based on supply chain coordination and does not consider rationality and fairness of allocation of profit increment. Also, the numerical analysis was given. The research shows some important conclusions: in the supply chain, the dominant manufacturer is not able to encourage the retailer to improve its promotion level by increasing its carbon cutting level, but the optimal emission reduction level increases with the dominant retailer’s promotion level; the optimal promotion level, emission reduction, and product demand in a retailer leading supply chain are higher than those in a supply chain dominated by manufacturer; with the new side-payment self-enforcing contract, decentralized decision according to individual rationality incurs a collective reason effect in the centralized setting. Liang-jie Xia and Hua-wei Zhi Copyright © 2014 Liang-jie Xia and Hua-wei Zhi. All rights reserved. A Method to Transit the Rotor-to-Stator Rubbing to Normal Motion Using the Phase Characteristic Mon, 11 Aug 2014 08:01:46 +0000 http://www.hindawi.com/journals/ddns/2014/247691/ A method is proposed to transit the rotor-to-stator rubbing to no-rub motion through active auxiliary bearing. The key point of this technique is to express the attractive domain of no-rub motion based on the phase characteristic and to represent the desired status. The feedback actuation is applied by an active auxiliary bearing to drive the rotor approaching the desired status. After that, the control actuation is turned off. Although the desired status is still in rubbing, it is in the attractive domain of no-rub motion, and the response of the rotor is automatically attracted to no-rub motion. Jieqiong Xu, Qunhong Li, and Shimin Wang Copyright © 2014 Jieqiong Xu et al. All rights reserved. Dynamic CGE Model and Simulation Analysis on the Impact of Citizenization of Rural Migrant Workers on the Labor and Capital Markets in China Mon, 11 Aug 2014 06:10:33 +0000 http://www.hindawi.com/journals/ddns/2014/351947/ This paper investigates the effect of the policy of citizenization of rural migrant workers on the factor market in a dynamic CGE model, which contains multiple dimensions of labor heterogeneity, a labor-lagged adjustment mechanism, and a dynamic investment mechanism. The simulation results show that changes in supply in the labor market will affect the labor market structure, the relative factor price, and the investment in and the output of industries. Qi Wu and Hao Xiao Copyright © 2014 Qi Wu and Hao Xiao. All rights reserved. Discrete Weighted Pseudo Asymptotic Periodicity of Second Order Difference Equations Sun, 10 Aug 2014 13:28:42 +0000 http://www.hindawi.com/journals/ddns/2014/949487/ We define the concept of discrete weighted pseudo--asymptotically periodic function and prove some basic results including composition theorem. We investigate the existence, and uniqueness of discrete weighted pseudo--asymptotically periodic solution to nonautonomous semilinear difference equations. Furthermore, an application to scalar second order difference equations is given. The working tools are based on the exponential dichotomy theory and fixed point theorem. Zhinan Xia Copyright © 2014 Zhinan Xia. All rights reserved. Linear Control of Fractional-Order Financial Chaotic Systems with Input Saturation Wed, 06 Aug 2014 08:51:36 +0000 http://www.hindawi.com/journals/ddns/2014/802429/ In this paper, control of fractional-order financial chaotic systems with saturated control input is investigated by means of state-feedback control method. The saturation problem is tackled by using Gronwall-Bellman lemma and a memoryless nonlinearity function. Based on Gronwall inequality and Laplace transform technique, two sufficient conditions are achieved for the asymptotical stability of the fractional-order financial chaotic systems with fractional orders 0 < α ≤ 1 and 1 < α < 2, respectively. Finally, simulation studies are carried out to show the effectiveness of the proposed linear control method. Junhai Luo, Guanjun Li, and Heng Liu Copyright © 2014 Junhai Luo et al. All rights reserved. A Proposal to the Study of Contractions in Quasi-Metric Spaces Wed, 06 Aug 2014 08:19:35 +0000 http://www.hindawi.com/journals/ddns/2014/269286/ We investigate the existence and uniqueness of a fixed point of an operator via simultaneous functions in the setting of complete quasi-metric spaces. Our results generalize and improve several recent results in literature. Hamed H. Alsulami, Erdal Karapınar, Farshid Khojasteh, and Antonio-Francisco Roldán-López-de-Hierro Copyright © 2014 Hamed H. Alsulami et al. All rights reserved. Coordinating Three-Level Supply Chain by Revenue-Sharing Contract with Sales Effort Dependent Demand Tue, 05 Aug 2014 00:00:00 +0000 http://www.hindawi.com/journals/ddns/2014/561081/ Revenue-sharing contract is a kind of mechanism to improve performance or to achieve perfect coordination of supply chain. Considering a three-level supply chain consisting of a manufacturer, a distributor, and a retailer who faces a stochastic and sales effort dependent demand, the paper analyzes the impact of sales effort on supply chain coordination and expounds the reasons why traditional revenue-sharing contract cannot coordinate supply chain in this condition. Given three cases: only the retailer bears the sales effort cost, only the manufacturer bears the sales effort cost, and the retailer bears the sales effort cost with the manufacturer, the paper proposes an improved revenue-sharing contract based on quantity discount policy to coordinate the supply chain. It illustrates that improved revenue sharing contract can coordinate supply chain by implementing it in one transaction or two transactions of three-level supply chain. The model of improved revenue-sharing contract is optimized, respectively, by addition form and multiplication form with sales effort dependent demand. Formulas are given to determine the optimal contract parameters. Finally, numerical experiments are given to test the accuracy of the model of improved revenue-sharing contract. Qinghua Pang, Yuer Chen, and Yulu Hu Copyright © 2014 Qinghua Pang et al. All rights reserved.