Discrete Dynamics in Nature and Society http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. Multiproduct Multiperiod Newsvendor Problem with Dynamic Market Efforts Thu, 20 Oct 2016 14:31:20 +0000 http://www.hindawi.com/journals/ddns/2016/7674027/ We study a multiperiod multiproduct production planning problem where the production capacity and the marketing effort on demand are both considered. The accumulative impact of marketing effort on demand is captured by the Nerlove and Arrow (N-A) advertising model. The problem is formulated as a discrete-time, finite-horizon dynamic optimization problem, which can be viewed as an extension to the classic newsvendor problem by integrating with the N-A model. A Lagrangian relaxation based solution approach is developed to solve the problem, in which the subgradient algorithm is used to find an upper bound of the solution and a feasibility heuristic algorithm is proposed to search for a feasible lower bound. Twelve kinds of instances with different problem size involving up to 50 products and 15 planning periods are randomly generated and used to test the Lagrangian heuristic algorithm. Computational results show that the proposed approach can obtain near optimal solutions for all the instances in very short CPU time, which is less than 90 seconds even for the largest instance. Jianmai Shi and Yiping Bao Copyright © 2016 Jianmai Shi and Yiping Bao. All rights reserved. Topological Entropy of One Type of Nonoriented Lorenz-Type Maps Thu, 20 Oct 2016 09:22:05 +0000 http://www.hindawi.com/journals/ddns/2016/6987471/ Constructing a Poincaré map is a method that is often used to study high-dimensional dynamical systems. In this paper, a geometric model of nonoriented Lorenz-type attractor is studied using this method, and its dynamical property is described. The topological entropy of one-dimensional nonoriented Lorenz-type maps is also computed in terms of their kneading sequences. Guo Feng Copyright © 2016 Guo Feng. All rights reserved. The Optimization Model for Interregional Power System Planning considering Carbon Emissions Trading and Renewable Energy Quota Mechanism Tue, 18 Oct 2016 14:16:09 +0000 http://www.hindawi.com/journals/ddns/2016/8784624/ In China, the rapid construction of ultra-high-voltage (UHV) transmission lines promotes interregional resource optimizing configuration and interregional power system planning. This paper analyzes external environment of interregional power system planning from geographical, technical, and policy environments. Then, the paper takes the minimum system investment cost as the optimization objective and constructs the optimization model of interregional power system planning considering carbon emissions trading (CET) and renewable energy quota mechanism (REQ). Finally, this paper sets base scenario, carbon emissions trading scenario, renewable energy quota mechanism scenario, and comprehensive scenario for case simulation. The results show that interregional power system planning could connect power grids in different regions, enlarge wind power consumption space, and relieve the inconformity problem between power resource and load demand. CET and REQ can increase the installed proportion of clean energy and reduce carbon dioxide emissions, but the cost of transmission lines construction and system reserve will increase correspondingly. The optimization effect of REQ on power system planning is better than CET. When they are both introduced, the power structure will reach the best, carbon dioxide emissions will achieve the minimum, and comprehensive benefits will become more balanced. Liwei Ju, Zhongfu Tan, Huanhuan Li, Qingkun Tan, Xiangyu Zhang, and Wei Zhang Copyright © 2016 Liwei Ju et al. All rights reserved. Minimizing Investment Risk of Integrated Rail and Transit-Oriented-Development Projects over Years in a Linear Monocentric City Tue, 18 Oct 2016 12:27:37 +0000 http://www.hindawi.com/journals/ddns/2016/1840673/ Rail and transit-oriented-development (TOD) projects are simultaneously optimized in this paper, with special consideration given to yearly variation and spatial and temporal correlation of population densities. In the proposed model, the objective is to minimize the investment risk of integrated rail and TOD projects with a given required expected return on investment. The investment risk is optimized based on closed-form solutions of the design variables, including rail line length, the number of TOD projects, and the number of housing units in each TOD project. The closed-form solutions are given explicitly under the assumption of social welfare maximization. It is found that underestimation exists for rail and TOD projects without consideration of the correlation of spatial and temporal population densities. TOD projects can greatly improve the return on investment of the rail operator. A numerical example is also presented. Ding Liu, Xi Jiang, Lingyun Meng, and Ying-En (Ethan) Ge Copyright © 2016 Ding Liu et al. All rights reserved. The Modeling and Control of a Singular Biological Economic System with Time Delay in a Polluted Environment Mon, 17 Oct 2016 13:39:51 +0000 http://www.hindawi.com/journals/ddns/2016/5036305/ This paper brings up the idea of a biological economic system with time delay in a polluted environment. Firstly, by proper linear transformation and parametric method, the singular time-delay systems are transformed to differential time-delay systems. Then, using center manifold theory and Poincare normal form method, the direction of Hopf bifurcation and the stability and period of its periodic orbits are analysed. At last, we have performed numerical simulation to support the analytical results. Yi Zhang, Huiying Zhao, and Qingling Zhang Copyright © 2016 Yi Zhang et al. All rights reserved. Research on Cooperative Innovation Behavior of Industrial Cluster Based on Subject Adaptability Sun, 16 Oct 2016 15:07:18 +0000 http://www.hindawi.com/journals/ddns/2016/3069065/ From the perspective of the interactive cooperation among subjects, this paper portrays the process of cooperative innovation in industrial cluster, in order to capture the correlated equilibrium relationship among them. Through the utilization of two key tools, evolutionary stable strategy and replicator dynamics equations, this paper considers the cost and gains of cooperative innovation and the amount of government support as well as other factors to build and analyze a classic evolutionary game model. On this basis, the subject’s own adaptability is introduced, which is regarded as the system noise in the stochastic evolutionary game model so as to analyze the impact of adaptability on the game strategy selection. The results show that, in the first place, without considering subjects’ adaptability, their cooperation in industrial clusters depends on the cost and gains of innovative cooperation, the amount of government support, and some conditions that can promote cooperation, namely, game steady state. In the second place after the introduction of subjects’ adaptability, it will affect both game theory selection process and time, which means that the process becomes more complex, presents the nonlinear characteristics, and helps them to make faster decisions in their favor, but the final steady state remains unchanged. Xiaohui Jia, Minghui Jiang, and Lei Shi Copyright © 2016 Xiaohui Jia et al. All rights reserved. Time-Compact Scheme for the One-Dimensional Dirac Equation Sun, 16 Oct 2016 12:04:26 +0000 http://www.hindawi.com/journals/ddns/2016/3670139/ Based on the Lie-algebra, a new time-compact scheme is proposed to solve the one-dimensional Dirac equation. This time-compact scheme is proved to satisfy the conservation of discrete charge and is unconditionally stable. The time-compact scheme is of fourth-order accuracy in time and spectral order accuracy in space. Numerical examples are given to test our results. Jun-Jie Cao, Xiang-Gui Li, Jing-Liang Qiu, and Jing-Jing Zhang Copyright © 2016 Jun-Jie Cao et al. All rights reserved. Positive Solutions of a Diffusive Predator-Prey System including Disease for Prey and Equipped with Dirichlet Boundary Condition Sun, 16 Oct 2016 07:53:53 +0000 http://www.hindawi.com/journals/ddns/2016/2323752/ We study a three-dimensional system of a diffusive predator-prey model including disease spread for prey and with Dirichlet boundary condition and Michaelis-Menten functional response. By semigroup method, we are able to achieve existence of a global solution of this system. Extinction of this system is established by spectral method. By using bifurcation theory and fixed point index theory, we obtain existence and nonexistence of inhomogeneous positive solutions of this system in steady state. Xiaoqing Wen, Yue Chen, and Hongwei Yin Copyright © 2016 Xiaoqing Wen et al. All rights reserved. Coordinated Learning by Model Difference Identification in Multiagent Systems with Sparse Interactions Wed, 12 Oct 2016 06:55:57 +0000 http://www.hindawi.com/journals/ddns/2016/3207460/ Multiagent Reinforcement Learning (MARL) is a promising technique for agents learning effective coordinated policy in Multiagent Systems (MASs). In many MASs, interactions between agents are usually sparse, and then a lot of MARL methods were devised for them. These methods divide learning process into independent learning and joint learning in coordinated states to improve traditional joint state-action space learning. However, most of those methods identify coordinated states based on assumptions about domain structure (e.g., dependencies) or agent (e.g., prior individual optimal policy and agent homogeneity). Moreover, situations that current methods cannot deal with still exist. In this paper, a modified approach is proposed to learn where and how to coordinate agents’ behaviors in more general MASs with sparse interactions. Our approach introduces sample grouping and a more accurate metric of model difference degree to identify which states of other agents should be considered in coordinated states, without strong additional assumptions. Experimental results show that the proposed approach outperforms its competitors by improving the average agent reward per step and works well in some broader scenarios. Qi Zhang, Peng Jiao, Quanjun Yin, and Lin Sun Copyright © 2016 Qi Zhang et al. All rights reserved. Linear Pursuit Differential Game under Phase Constraint on the State of Evader Mon, 10 Oct 2016 06:35:45 +0000 http://www.hindawi.com/journals/ddns/2016/1289456/ We consider a linear pursuit differential game of one pursuer and one evader. Controls of the pursuer and evader are subjected to integral and geometric constraints, respectively. In addition, phase constraint is imposed on the state of evader, whereas pursuer moves throughout the space. We say that pursuit is completed, if inclusion is satisfied at some , where and are states of pursuer and evader, respectively, and is terminal set. Conditions of completion of pursuit in the game from all initial points of players are obtained. Strategy of the pursuer is constructed so that the phase vector of the pursuer first is brought to a given set, and then pursuit is completed. Askar Rakhmanov, Gafurjan Ibragimov, and Massimiliano Ferrara Copyright © 2016 Askar Rakhmanov et al. All rights reserved. Venture Investment Incentive Mechanisms and Simulation with Venture Entrepreneurs Having Multistage Efforts Based on Fairness Preference Theory Mon, 10 Oct 2016 05:53:07 +0000 http://www.hindawi.com/journals/ddns/2016/5862576/ When venture capital has been invested into venture companies, venture capitalists and venture entrepreneurs form a principal-agent relationship. Take into account the fact that the venture entrepreneur’s effort is a long process, because the effort is not the same at different stage. Therefore, efforts variables are seen as the multistage dynamic variable, and venture investment principal-agent model with venture entrepreneurs having multistage efforts is constructed on the basis of the classic principal-agent theory in the paper. Further, in the later stage effort of venture entrepreneurs is affected by the size of prestage benefit with venture capitalists and venture entrepreneurs; thus the fairness preference model is improved, and venture investment principal-agent model with venture entrepreneurs having multistage efforts is constructed on the basis of fairness preference theory. Both theoretical derivation and simulation have demonstrated that, under the condition of information asymmetry, if the fairness preference of venture entrepreneurs holds, then venture capitalists provide venture entrepreneurs with level higher than that without fairness preference, in every single stage venture entrepreneurs make efforts higher than those without fairness preference, and in two periods both venture investors and venture entrepreneurs gain total real gains higher than those in two periods without fair preference. Kaihong Wang, Chuan Ding, Jiacheng Chen, and Aimin Li Copyright © 2016 Kaihong Wang et al. All rights reserved. An Extreme Learning Machine Based on the Mixed Kernel Function of Triangular Kernel and Generalized Hermite Dirichlet Kernel Tue, 04 Oct 2016 12:24:40 +0000 http://www.hindawi.com/journals/ddns/2016/7293278/ According to the characteristics that the kernel function of extreme learning machine (ELM) and its performance have a strong correlation, a novel extreme learning machine based on a generalized triangle Hermitian kernel function was proposed in this paper. First, the generalized triangle Hermitian kernel function was constructed by using the product of triangular kernel and generalized Hermite Dirichlet kernel, and the proposed kernel function was proved as a valid kernel function of extreme learning machine. Then, the learning methodology of the extreme learning machine based on the proposed kernel function was presented. The biggest advantage of the proposed kernel is its kernel parameter values only chosen in the natural numbers, which thus can greatly shorten the computational time of parameter optimization and retain more of its sample data structure information. Experiments were performed on a number of binary classification, multiclassification, and regression datasets from the UCI benchmark repository. The experiment results demonstrated that the robustness and generalization performance of the proposed method are outperformed compared to other extreme learning machines with different kernels. Furthermore, the learning speed of proposed method is faster than support vector machine (SVM) methods. Senyue Zhang and Wenan Tan Copyright © 2016 Senyue Zhang and Wenan Tan. All rights reserved. A New Model of Stopping Sight Distance of Curve Braking Based on Vehicle Dynamics Tue, 04 Oct 2016 11:14:19 +0000 http://www.hindawi.com/journals/ddns/2016/4260705/ Compared with straight-line braking, cornering brake has longer braking distance and poorer stability. Therefore, drivers are more prone to making mistakes. The braking process and the dynamics of vehicles in emergency situations on curves were analyzed. A biaxial four-wheel vehicle was simplified to a single model. Considering the braking process, dynamics, force distribution, and stability, a stopping sight distance of the curve braking calculation model was built. Then a driver-vehicle-road simulation platform was built using multibody dynamic software. The vehicle test of brake-in-turn was realized in this platform. The comparison of experimental and calculated values verified the reliability of the computational model. Eventually, the experimental values and calculated values were compared with the stopping sight distance recommended by the Highway Route Design Specification (JTGD20-2006); the current specification of stopping sight distance does not apply to cornering brake sight distance requirements. In this paper, the general values and limits of the curve stopping sight distance are presented. Rong-xia Xia, De-hua Wu, Jie He, Ya Liu, and Deng-feng Shi Copyright © 2016 Rong-xia Xia et al. All rights reserved. Efficient Lattice Method for Valuing of Options with Barrier in a Regime Switching Model Mon, 03 Oct 2016 13:53:29 +0000 http://www.hindawi.com/journals/ddns/2016/2474305/ We propose an efficient lattice method for valuation of options with barrier in a regime switching model. Specifically, we extend the trinomial tree method of Yuen and Yang (2010) by calculating the local average of prices near a node of the lattice. The proposed method reduces oscillations of the lattice method for pricing barrier options and improves the convergence speed. Finally, computational results for the valuation of options with barrier show that the proposed method with interpolation is more efficient than the other tree methods. Youngchul Han and Geonwoo Kim Copyright © 2016 Youngchul Han and Geonwoo Kim. All rights reserved. Modeling the Frequency of Cyclists’ Red-Light Running Behavior Using Bayesian PG Model and PLN Model Wed, 28 Sep 2016 14:08:51 +0000 http://www.hindawi.com/journals/ddns/2016/2593698/ Red-light running behaviors of bicycles at signalized intersection lead to a large number of traffic conflicts and high collision potentials. The primary objective of this study is to model the cyclists’ red-light running frequency within the framework of Bayesian statistics. Data was collected at twenty-five approaches at seventeen signalized intersections. The Poisson-gamma (PG) and Poisson-lognormal (PLN) model were developed and compared. The models were validated using Bayesian values based on posterior predictive checking indicators. It was found that the two models have a good fit of the observed cyclists’ red-light running frequency. Furthermore, the PLN model outperformed the PG model. The model estimated results showed that the amount of cyclists’ red-light running is significantly influenced by bicycle flow, conflict traffic flow, pedestrian signal type, vehicle speed, and e-bike rate. The validation result demonstrated the reliability of the PLN model. The research results can help transportation professionals to predict the expected amount of the cyclists’ red-light running and develop effective guidelines or policies to reduce red-light running frequency of bicycles at signalized intersections. Yao Wu, Jian Lu, Hong Chen, and Qian Wan Copyright © 2016 Yao Wu et al. All rights reserved. Analyzing the Impact of Trucks on Traffic Flow Based on an Improved Cellular Automaton Model Mon, 26 Sep 2016 16:35:38 +0000 http://www.hindawi.com/journals/ddns/2016/1236846/ This paper aims to analyze the impact of trucks on traffic flow and propose an improved cellular automaton model, which considers both the performance difference between passenger cars and trucks and the behaviour change of passenger cars under the impact of trucks. A questionnaire survey has been conducted to find out whether the impact of trucks exists and how the behaviour of passenger car drivers changes under the impact of trucks. The survey results confirm that the impact of trucks exists and indicate that passenger car drivers will enlarge the space gap, decelerate, and change lanes in advance when they are affected. Simulation results show that traffic volume is still affected by percentages of trucks in the congestion phase in the proposed model compared with traditional heterogeneous cellular automaton models. Traffic volume and speed decrease with the impact of trucks in the congestion phase. The impact of trucks can increase traffic congestion as it increases. However, it has different influences on the speed variance of passenger cars in different occupancies. In the proposed model, the relative relationship of the space gap between car-following-truck and car-following-car is changeable at a certain value of occupancy, which is related to the impact of trucks. Dewen Kong, Xiucheng Guo, Bo Yang, and Dingxin Wu Copyright © 2016 Dewen Kong et al. All rights reserved. Strategic Deconfliction of 4D Trajectory and Perturbation Analysis for Air Traffic Control and Automation System Sun, 25 Sep 2016 13:32:52 +0000 http://www.hindawi.com/journals/ddns/2016/7028305/ Strategic 4D trajectory conflict-free planning is recognized as one of the core technologies of next-generation air traffic control and automation systems. To resolve potential conflicts during strategic 4D conflict-free trajectory planning, a protection-zone conflict-control model based on air traffic control separation constraints was proposed, in which relationships between expected arrival time and adjusted arrival time at conflicting waypoints for aircraft queues were built and transformed into dynamic linear equations under the definition of max-plus algebra. A method for strategic deconfliction of 4D trajectory was then proposed using two strategies: arrival time adjustment and departure time adjustment. In addition, departure time and flight duration perturbations were introduced to analyze the sensitivity of the planned strategic conflict-free 4D trajectories, and a robustness index for the conflict-free 4D trajectories was calculated. Finally, the proposed method was tested for the Shanghai air traffic control terminal area. The outcomes demonstrated that the planned strategic conflict-free 4D trajectories could avoid potential conflicts, and the slack time could be used to indicate their robustness. Complexity analysis demonstrated that deconfliction using max-plus algebra is more suitable for deconfliction of 4D trajectory with random sampling period in fix air route. Xinmin Tang, Yu Zhang, Ping Chen, Bo Li, and Songchen Han Copyright © 2016 Xinmin Tang et al. All rights reserved. The Hyper-Wiener Index of Trees of Order with Diameter Thu, 22 Sep 2016 14:18:47 +0000 http://www.hindawi.com/journals/ddns/2016/7241349/ The hyper-Wiener index is a kind of extension of the Wiener index, used for predicting physicochemical properties of organic compounds. The hyper-Wiener index is defined as with the summation going over all pairs of vertices in , and denotes the distance of the two vertices and in the graph . In this paper, we obtain the second-minimum hyper-Wiener indices among all the trees with vertices and diameter and characterize the corresponding extremal graphs. Gaixiang Cai, Guidong Yu, Jinde Cao, Ahmad Alsaedi, and Fuad Alsaadi Copyright © 2016 Gaixiang Cai et al. All rights reserved. On a Five-Dimensional Nonautonomous Schistosomiasis Model with Latent Period Thu, 22 Sep 2016 11:21:29 +0000 http://www.hindawi.com/journals/ddns/2016/8707258/ A five-dimensional nonautonomous schistosomiasis model which include latent period is proposed and studied. By constructing several auxiliary functions and using some skills, we obtain some sufficient conditions for the extinction and permanence (uniform persistence) of infectious population of the model. New threshold values of integral form are obtained. For the corresponding autonomous schistosomiasis model, our results are consistent with the past results. For the periodic and almost periodic cases, some corollaries for the extinction and permanence of the disease are established. In order to illustrate our theoretical analysis, some numerical simulations are presented. Shujing Gao, Yanfei Dai, and Dehui Xie Copyright © 2016 Shujing Gao et al. All rights reserved. Certain Concepts in -Polar Fuzzy Graph Structures Thu, 22 Sep 2016 09:16:17 +0000 http://www.hindawi.com/journals/ddns/2016/6301693/ We apply the concept of -polar fuzzy sets to graph structures. We introduce certain concepts in -polar fuzzy graph structures, including strong -polar fuzzy graph structure, -polar fuzzy -cycle, -polar fuzzy -tree, -polar fuzzy -cut vertex, and -polar fuzzy -bridge, and we illustrate these concepts by several examples. We present the notions of -complement of an -polar fuzzy graph structure and self-complementary, strong self-complementary, totally strong self-complementary -polar fuzzy graph structures, and we investigate some of their properties. Muhammad Akram, Noura Alshehri, and Rabia Akmal Copyright © 2016 Muhammad Akram et al. All rights reserved. Backup Sourcing Decisions for Coping with Supply Disruptions under Long-Term Horizons Wed, 21 Sep 2016 08:05:33 +0000 http://www.hindawi.com/journals/ddns/2016/6716058/ This paper studies a buyer’s inventory control problem under a long-term horizon. The buyer has one major supplier that is prone to disruption risks and one backup supplier with higher wholesale price. Two kinds of sourcing methods are available for the buyer: single sourcing with/without contingent supply and dual sourcing. In contingent sourcing, the backup supplier is capacitated and/or has yield uncertainty, whereas in dual sourcing the backup supplier has an incentive to offer output flexibility during disrupted periods. The buyer’s expected cost functions and the optimal base-stock levels using each sourcing method under long-term horizon are obtained, respectively. The effects of three risk parameters, disruption probability, contingent capacity or uncertainty, and backup flexibility, are examined using comparative studies and numerical computations. Four sourcing methods, namely, single sourcing with contingent supply, dual sourcing, and single sourcing from either of the two suppliers, are also compared. These findings can be used as a valuable guideline for companies to select an appropriate sourcing strategy under supply disruption risks. Jing Hou and Lijun Sun Copyright © 2016 Jing Hou and Lijun Sun. All rights reserved. State-Dependent Impulsive Control Strategies for a Tumor-Immune Model Tue, 20 Sep 2016 16:42:07 +0000 http://www.hindawi.com/journals/ddns/2016/2979414/ Controlling the number of tumor cells leads us to expect more efficient strategies for treatment of tumor. Towards this goal, a tumor-immune model with state-dependent impulsive treatments is established. This model may give an efficient treatment schedule to control tumor’s abnormal growth. By using the Poincaré map and analogue of Poincaré criterion, some conditions for the existence and stability of a positive order-1 periodic solution of this model are obtained. Moreover, we carry out numerical simulations to illustrate the feasibility of our main results and compare fixed-time impulsive treatment effects with state-dependent impulsive treatment effects. The results of our simulations say that, in determining optimal treatment timing, the model with state-dependent impulsive control is more efficient than that with fixed-time impulsive control. Kwang Su Kim, Giphil Cho, Lin-Fei Nie, and Il Hyo Jung Copyright © 2016 Kwang Su Kim et al. All rights reserved. On the Singularity of Multivariate Hermite Interpolation of Total Degree Tue, 20 Sep 2016 13:36:28 +0000 http://www.hindawi.com/journals/ddns/2016/7515876/ We study the singularity of multivariate Hermite interpolation of type total degree on nodes with . We first check the number of the interpolation conditions and the dimension of interpolation space. And then the singularity of the interpolation schemes is decided for most cases. Also some regular interpolation schemes are derived, a few of which are proved due to theoretical argument and most of which are verified by numerical method. There are some schemes to be decided and left open. Zhongyong Hu, Zhaoliang Meng, and Zhongxuan Luo Copyright © 2016 Zhongyong Hu et al. All rights reserved. Qualitative and Bifurcation Analysis of an SIR Epidemic Model with Saturated Treatment Function and Nonlinear Pulse Vaccination Sun, 18 Sep 2016 14:05:50 +0000 http://www.hindawi.com/journals/ddns/2016/9146481/ An SIR epidemic model with saturated treatment function and nonlinear pulse vaccination is studied. The existence and stability of the disease-free periodic solution are investigated. The sufficient conditions for the persistence of the disease are obtained. The existence of the transcritical and flip bifurcations is considered by means of the bifurcation theory. The stability of epidemic periodic solutions is discussed. Furthermore, some numerical simulations are given to illustrate our results. Xiangsen Liu and Binxiang Dai Copyright © 2016 Xiangsen Liu and Binxiang Dai. All rights reserved. Discrete Chaotic Dynamics for Economics and Social Science Thu, 15 Sep 2016 11:50:27 +0000 http://www.hindawi.com/journals/ddns/2016/3105084/ Christos K. Volos, Sundarapandian Vaidyanathan, Viet-Thanh Pham, and Esteban Tlelo-Cuautle Copyright © 2016 Christos K. Volos et al. All rights reserved. An Image Encryption Scheme Based on DNA Computing and Cellular Automata Thu, 08 Sep 2016 13:00:45 +0000 http://www.hindawi.com/journals/ddns/2016/5408529/ Networks have developed very quickly, allowing the speedy transfer of image information through Internet. However, the openness of these networks poses a serious threat to the security of image information. The field of image encryption has drawn attention for this reason. In this paper, the concepts of 1-dimensional DNA cellular automata and T-DNA cellular automata are defined, and the concept of reversible T-DNA cellular automata is introduced. An efficient approach to encryption involving reversible T-DNA cellular automata as an encryption tool and natural DNA sequences as the main keys is here proposed. The results of a simulation experiment, performance analysis, and comparison to other encryption algorithms showed this algorithm to be capable of resisting brute force attacks, statistical attacks, and differential attacks. It also enlarged the key space enormously. It meets the criteria for one-time pad and resolves the problem that one-time pad is difficult to save. Shihua Zhou, Bin Wang, Xuedong Zheng, and Changjun Zhou Copyright © 2016 Shihua Zhou et al. All rights reserved. The Impact of Subway Lines on Residential Property Values in Tianjin: An Empirical Study Based on Hedonic Pricing Model Thu, 08 Sep 2016 08:17:44 +0000 http://www.hindawi.com/journals/ddns/2016/1478413/ The construction of subways has an external impact on the urban environment. Among them, the most important acceleration function lies in the property values of housing near subway stations. Tianjin, the largest open coastal city in Northern China, is selected as the subject of the research in this paper by virtue of its unique background. The Hedonic Pricing Model is used in analysing the change in the value of the properties located within 1,000 metres of completed subway line 3 stations. Using the theories of land rent and land location, and a model of the impact of urban traffic on the surrounding real estate prices, we analyse the sphere of influence of Tianjin Metro Line 3 on real estate prices. Finally, the paper stresses the importance of urban construction and subway building and finds that different development strategies should be used according to the characteristics of the subway in various regions of the city. Hui Sun, Yuning Wang, and Qingbo Li Copyright © 2016 Hui Sun et al. All rights reserved. The Time Lags Effects of Innovation Input on Output in National Innovation Systems: The Case of China Wed, 07 Sep 2016 16:40:54 +0000 http://www.hindawi.com/journals/ddns/2016/1963815/ This paper investigates the time lags effects of innovation input on output in the national innovation systems (NIS). Firstly, we analyze the intrinsic properties of China’s NIS based on the conceptual framework and the causal loop diagram. Secondly, we construct a time lags distribution calculation model and employ the main innovation input indicators to measure the specific characteristics of time lags effects of innovation input on output for China in the period 2000–2012. The results indicate that there are considerable time lags in the four major feedback loops, and the distribution of time lags is various according to the characteristics of innovation input and influencing factors in the internal transformation. The trends of time lags from R&D personnel and industry-academia-research collaboration show steady growth, and the trends of time lags from R&D expenditure and government’s macro-control take inverted U-shaped pattern. Finally, we combine the estimation results of lags distribution calculation model with the analysis results of the causal loop diagram (including positive loops and negative loops) to provide some innovation policy suggestions. This study provides important implications for our understanding of the long-term complex lags effects of innovation input on output as well as for policy-makers designing and implementing the innovation strategies. Dan Wang, Xinli Zhao, and Zhenshan Zhang Copyright © 2016 Dan Wang et al. All rights reserved. Number of Forts in Iterated Logistic Mapping Wed, 07 Sep 2016 13:25:36 +0000 http://www.hindawi.com/journals/ddns/2016/4682168/ Using the theory of complete discrimination system and the computer algebra system MAPLE V.17, we compute the number of forts for the logistic mapping on parameterized by . We prove that if then the number of forts does not increase under iteration and that if then the number of forts is not bounded under iteration. Furthermore, we focus on the case of and give for each some critical values of for the change of numbers of forts. Kaixuan Yu and Zhiheng Yu Copyright © 2016 Kaixuan Yu and Zhiheng Yu. All rights reserved. On the Limit Cycles for Continuous and Discontinuous Cubic Differential Systems Wed, 07 Sep 2016 11:54:41 +0000 http://www.hindawi.com/journals/ddns/2016/4939780/ We study the number of limit cycles for the quadratic polynomial differential systems , having an isochronous center with continuous and discontinuous cubic polynomial perturbations. Using the averaging theory of first order, we obtain that 3 limit cycles bifurcate from the periodic orbits of the isochronous center with continuous perturbations and at least 7 limit cycles bifurcate from the periodic orbits of the isochronous center with discontinuous perturbations. Moreover, this work shows that the discontinuous systems have at least 4 more limit cycles surrounding the origin than the continuous ones. Ziguo Jiang Copyright © 2016 Ziguo Jiang. All rights reserved.