Journal of Applied Mathematics http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Modelling Laser Milling of Microcavities for the Manufacturing of DES with Ensembles Thu, 17 Apr 2014 14:53:10 +0000 http://www.hindawi.com/journals/jam/2014/439091/ A set of designed experiments, involving the use of a pulsed Nd:YAG laser system milling 316L Stainless Steel, serve to study the laser-milling process of microcavities in the manufacture of drug-eluting stents (DES). Diameter, depth, and volume error are considered to be optimized as functions of the process parameters, which include laser intensity, pulse frequency, and scanning speed. Two different DES shapes are studied that combine semispheres and cylinders. Process inputs and outputs are defined by considering the process parameters that can be changed under industrial conditions and the industrial requirements of this manufacturing process. In total, 162 different conditions are tested in a process that is modeled with the following state-of-the-art data-mining regression techniques: Support Vector Regression, Ensembles, Artificial Neural Networks, Linear Regression, and Nearest Neighbor Regression. Ensemble regression emerged as the most suitable technique for studying this industrial problem. Specifically, Iterated Bagging ensembles with unpruned model trees outperformed the other methods in the tests. This method can predict the geometrical dimensions of the machined microcavities with relative errors related to the main average value in the range of 3 to 23%, which are considered very accurate predictions, in view of the characteristics of this innovative industrial task. Pedro Santos, Daniel Teixidor, Jesus Maudes, and Joaquim Ciurana Copyright © 2014 Pedro Santos et al. All rights reserved. Generalized Dimensional Ostrowski Type and Grüss Type Inequalities on Time Scales Thu, 17 Apr 2014 14:52:29 +0000 http://www.hindawi.com/journals/jam/2014/434958/ Some new generalized dimensional Ostrowski type and Grüss type integral inequalities on time scales are established in this paper. The present results unify continuous and discrete analysis, and extend some known results in the literature. Bin Zheng and Qinghua Feng Copyright © 2014 Bin Zheng and Qinghua Feng. All rights reserved. Discussion for -Matrices and It’s Application Thu, 17 Apr 2014 13:12:16 +0000 http://www.hindawi.com/journals/jam/2014/870592/ Nonsingular -matrices and positive stable matrices play an important role in the stability of neural network system. In this paper, some criteria for nonsingular -matrices are obtained by the theory of diagonally dominant matrices and the obtained result is introduced into identifying the stability of neural networks. So the criteria for nonsingular -matrices are expanded and their application on neural network system is given. Finally, the effectiveness of the results is illustrated by numerical examples. Guichun Han, Huishuang Gao, and Haitao Yang Copyright © 2014 Guichun Han et al. All rights reserved. Optimal Spatial Matrix Filter Design for Array Signal Preprocessing Thu, 17 Apr 2014 13:03:16 +0000 http://www.hindawi.com/journals/jam/2014/564976/ An efficient technique of designing spatial matrix filter for array signal preprocessing based on convex programming was proposed. Five methods were considered for designing the filter. In design method 1, we minimized the passband fidelity subject to the controlled overall stopband attenuation level. In design method 2, the objective function and the constraint in the design method 1 were reversed. In design method 3, the optimal matrix filter which has the general mean square error was considered. In design method 4, the left stopband and the right stopband were constrained with specific attenuation level each, and the minimized passband fidelity was received. In design method 5, the optimization objective function was the sum of the left stopband and the right stopband attenuation levels with the weighting factors 1 and γ, respectively, and the passband fidelity was the constraints. The optimal solution of the optimizations above was derived by the Lagrange multiplier theory. The relations between the optimal solutions were analyzed. The generalized singular value decomposition was introduced to simplify the optimal solution of design methods 1 and 2 and enhanced the efficiency of solving the Lagrange multipliers. By simulations, it could be found that the proposed method was effective for designing the spatial matrix filter. Haiyong Zhang, Dong Han, Kai Ji, Zhong Ren, Chi Xu, Lijuan Zhu, and Hongyan Tan Copyright © 2014 Haiyong Zhang et al. All rights reserved. A General Approximation Method for a Kind of Convex Optimization Problems in Hilbert Spaces Thu, 17 Apr 2014 12:10:09 +0000 http://www.hindawi.com/journals/jam/2014/156073/ The constrained convex minimization problem is to find a point with the property that , and   , , where is a nonempty, closed, and convex subset of a real Hilbert space , is a real-valued convex function, and is not Fréchet differentiable, but lower semicontinuous. In this paper, we discuss an iterative algorithm which is different from traditional gradient-projection algorithms. We firstly construct a bifunction defined as . And we ensure the equilibrium problem for equivalent to the above optimization problem. Then we use iterative methods for equilibrium problems to study the above optimization problem. Based on Jung’s method (2011), we propose a general approximation method and prove the strong convergence of our algorithm to a solution of the above optimization problem. In addition, we apply the proposed iterative algorithm for finding a solution of the split feasibility problem and establish the strong convergence theorem. The results of this paper extend and improve some existing results. Ming Tian and Li-Hua Huang Copyright © 2014 Ming Tian and Li-Hua Huang. All rights reserved. The Approximate Solution of Fredholm Integral Equations with Oscillatory Trigonometric Kernels Thu, 17 Apr 2014 12:06:04 +0000 http://www.hindawi.com/journals/jam/2014/172327/ A method for approximating the solution of weakly singular Fredholm integral equation of the second kind with highly oscillatory trigonometric kernel is presented. The unknown function is approximated by expansion of Chebychev polynomial and the coefficients are determinated by classical collocation method. Due to the highly oscillatory kernels of integral equation, the discretised collocation equation will give rise to the computation of oscillatory integrals. These integrals are calculated by using recursion formula derived from the fundamental recurrence relation of Chebyshev polynomial. The effectiveness and accuracy of the proposed method are tested by numerical examples. Qinghua Wu Copyright © 2014 Qinghua Wu. All rights reserved. Advanced Techniques in Computational Mechanics Thu, 17 Apr 2014 07:52:49 +0000 http://www.hindawi.com/journals/jam/2014/785181/ Luís Godinho, Daniel Dias-da-Costa, António Tadeu, and Delfim Soares Jr. Copyright © 2014 Luís Godinho et al. All rights reserved. The Determinants, Inverses, Norm, and Spread of Skew Circulant Type Matrices Involving Any Continuous Lucas Numbers Thu, 17 Apr 2014 06:40:15 +0000 http://www.hindawi.com/journals/jam/2014/239693/ We consider the skew circulant and skew left circulant matrices with any continuous Lucas numbers. Firstly, we discuss the invertibility of the skew circulant matrices and present the determinant and the inverse matrices by constructing the transformation matrices. Furthermore, the invertibility of the skew left circulant matrices is also discussed. We obtain the determinants and the inverse matrices of the skew left circulant matrices by utilizing the relationship between skew left circulant matrices and skew circulant matrix, respectively. Finally, the four kinds of norms and bounds for the spread of these matrices are given, respectively. Jin-jiang Yao and Zhao-lin Jiang Copyright © 2014 Jin-jiang Yao and Zhao-lin Jiang. All rights reserved. Lightweight Design of an Outer Tie Rod for an Electrical Vehicle Thu, 17 Apr 2014 06:09:32 +0000 http://www.hindawi.com/journals/jam/2014/942645/ The lightweight design of the outer tie rod installed on an electrical vehicle was achieved through material selection and optimization technique. The aluminum alloy Al6082M was selected as a steel-substitute, and its structural shape was optimized by applying metamodel-based optimization. In this process, finite element analysis was performed to predict the structural responses, such as buckling resistance and fatigue life. First, for an arbitrary base design made of steel, the structural responses were calculated. Then, the design variables were defined to find a lightweight design made of Al6082M. Secondly, metamodel-based optimization based on the kriging interpolation method was applied, leading to determination of an optimum design. The suggested optimum design has the minimum weight satisfying the critical design requirement. Finally, the numerical results of the buckling resistance and fatigue life were validated, through bucking and fatigue tests. Young-Chul Park, Seung-Kul Baek, Bu-Kyo Seo, Jong-Kyu Kim, and Kwon-Hee Lee Copyright © 2014 Young-Chul Park et al. All rights reserved. Metaheuristic Algorithm for Solving Biobjective Possibility Planning Model of Location-Allocation in Disaster Relief Logistics Thu, 17 Apr 2014 00:00:00 +0000 http://www.hindawi.com/journals/jam/2014/239868/ Thousands of victims and millions of affected people are hurt by natural disasters every year. Therefore, it is essential to prepare proper response programs that consider early activities of disaster management. In this paper, a multiobjective model for distribution centers which are located and allocated periodically to the damaged areas in order to distribute relief commodities is offered. The main objectives of this model are minimizing the total costs and maximizing the least rate of the satisfaction in the sense of being fair while distributing the items. The model simultaneously determines the location of relief distribution centers and the allocation of affected areas to relief distribution centers. Furthermore, an efficient solution approach based on genetic algorithm has been developed in order to solve the proposed mathematical model. The results of genetic algorithm are compared with the results provided by simulated annealing algorithm and LINGO software. The computational results show that the proposed genetic algorithm provides relatively good solutions in a reasonable time. Farnaz Barzinpour, Mohsen Saffarian, Ahmad Makoui, and Ebrahim Teimoury Copyright © 2014 Farnaz Barzinpour et al. All rights reserved. Grey Target Decision Method for a Variable Target Centre Based on the Decision Maker’s Preferences Thu, 17 Apr 2014 00:00:00 +0000 http://www.hindawi.com/journals/jam/2014/572529/ In multiattribute grey target decision making, the decision maker (DM) may have certain preferences for some attributes. The impacts of two types of DM’s preferences for some attribute values on alternatives were studied. To deal with the attribute preferences of a DM, a generalised grey target decision method was presented. The proposed method required that the index values of all alternatives were not normalised. The target centre index values can be obtained by substituting DM’s preference values for some of the original target centre index values as determined by the alternatives themselves. Following this, the proposed generalised method was used to calculate the target centre distances. A case study showed that this method of handling DM’s preferences for some attributes was effective. Jinshan Ma Copyright © 2014 Jinshan Ma. All rights reserved. A New Method for Predicting the Position of Gas Influx Based on PRP in Drilling Operations Wed, 16 Apr 2014 14:15:21 +0000 http://www.hindawi.com/journals/jam/2014/969465/ Accurately predicting the position of gas influx not only helps to analyze complex formation structure, but also can provide reference for taking effective measure, such as increasing mud density, increasing back pressure and casing packer, to suppress the gas influx. Predicting the accurate position of gas influx has been one of the urgent difficulties for drilling industry. With full consideration of the important factors such as the virtual mass force, viscous shear force, energy exchange, and narrow resistance, a new method for predicting the position of gas influx has been proposed based on pressure response time calculation. The gas equations of state (EOS), small perturbation theory, and the fourth-order Runge-Kutta method (R-K4) are adopted to solve the model. Also, the pressure response time plate (PRP) which presents the corresponding relationship between position of gas influx and wellhead parameters by several pressure wave response curves calculated by computer programming is given. The results showed that the PRP is unique at different well depth and gas influx rate, and the position of gas influx can be accurately determined by PRP with known wellhead parameters and detected response time. Therefore, without the help of downhole tools, the accurate mathematical method for predicting the position of gas influx is completely feasible. Xiangwei Kong, Yuanhua Lin, and Yijie Qiu Copyright © 2014 Xiangwei Kong et al. All rights reserved. Adaptive Failure Identification for Healthcare Risk Analysis and Its Application on E-Healthcare Wed, 16 Apr 2014 08:58:15 +0000 http://www.hindawi.com/journals/jam/2014/865241/ To satisfy the requirement for diverse risk preferences, we propose a generic risk priority number (GRPN) function that assigns a risk weight to each parameter such that they represent individual organization/department/process preferences for the parameters. This research applies GRPN function-based model to differentiate the types of risk, and primary data are generated through simulation. We also conduct sensitivity analysis on correlation and regression to compare it with the traditional RPN (TRPN). The proposed model outperforms the TRPN model and provides a practical, effective, and adaptive method for risk evaluation. In particular, the defined GRPN function offers a new method to prioritize failure modes in failure mode and effect analysis (FMEA). The different risk preferences considered in the healthcare example show that the modified FMEA model can take into account the various risk factors and prioritize failure modes more accurately. In addition, the model also can apply to a generic e-healthcare service environment with a hierarchical architecture. Kuo-Chung Chu and Lun-Ping Hung Copyright © 2014 Kuo-Chung Chu and Lun-Ping Hung. All rights reserved. Geometrical Variable Weights Buffer GM(1,1) Model and Its Application in Forecasting of China’s Energy Consumption Tue, 15 Apr 2014 16:16:22 +0000 http://www.hindawi.com/journals/jam/2014/131432/ In order to improve the application area and the prediction accuracy of GM(1,1) model, a novel Grey model is proposed in this paper. To remedy the defects about the applications of traditional Grey model and buffer operators in medium- and long-term forecasting, a Variable Weights Buffer Grey model is proposed. The proposed model integrates the variable weights buffer operator with the background value optimized GM(1,1) model to implement dynamic preprocessing of original data. Taking the maximum degree of Grey incidence between fitting value and actual value as objective function, then the optimal buffer factor is chosen, which can improve forecasting precision, make forecasting results embodying the internal trend of original data to the maximum extent, and improve the stability of the prediction. To verify the effectiveness of the proposed model, the energy consumption in China from 2002 to 2009 is used for the modeling to forecast the energy consumption in China from 2010 to 2020, and the forecasting results prove that the GVGM(1,1) model has remarkably improved the forecasting ability of medium- and long-term energy consumption in China. Wei Li and Han Xie Copyright © 2014 Wei Li and Han Xie. All rights reserved. Measurement of Congestion in the Simultaneous Presence of Desirable and Undesirable Outputs Tue, 15 Apr 2014 14:12:45 +0000 http://www.hindawi.com/journals/jam/2014/512157/ The concept of congestion, which is mainly applied in economics, refers to a situation where inputs are overinvested. Many studies have focused on congestion measurement by means of data envelopment analysis (DEA). However, most of the previous investigations only considered the framework of desirable outputs. In fact, firms in the real world unavoidably generate undesirable outputs (such as pollutants or wastes) along with desirable outputs. Therefore, a new scheme is required for measuring congestion in the simultaneous presence of both desirable and undesirable outputs. This paper develops a nonradial efficiency measure for including undesirable outputs into the environmental performance. Based on the proposed model, a new definition and a new approach are presented to deal with congestion in the simultaneous presence of desirable and undesirable outputs. Then, this paper uses the presented method to study the pollutants (waste gas emission and waste discharge) of 31 administrative regions of China. The finding indicates that 7 industries pay attention to the reduction of their pollutants accompanying improvement of their commercial targets. Consequently, they do not show congestion in any input. H. Zare-Haghighi, M. Rostamy-Malkhalifeh, and G. R. Jahanshahloo Copyright © 2014 H. Zare-Haghighi et al. All rights reserved. New Travelling Wave Solutions for Sine-Gordon Equation Tue, 15 Apr 2014 13:41:41 +0000 http://www.hindawi.com/journals/jam/2014/841416/ We propose a method to deal with the general sine-Gordon equation. Several new exact travelling wave solutions with the form of JacobiAmplitude function are derived for the general sine-Gordon equation by using some reasonable transformation. Compared with previous solutions, our solutions are more general than some of the previous. Yunchuan Sun Copyright © 2014 Yunchuan Sun. All rights reserved. Fare Design in Urban Transit Network considering Elastic Demand and Adverse Weather’s Impact Tue, 15 Apr 2014 12:50:19 +0000 http://www.hindawi.com/journals/jam/2014/197515/ Due to the disturbance of unexpected effects and adverse weather conditions, transit supply and demand manifests many uncertainties. In this paper, we take account of these uncertainties and propose a transit fare structure design model including both ground and underground public transportation. Such transit fare design problem is described through bilevel programming, in which the upper level is the transportation authority’s transit fare structure decision aiming to minimize the transit network’s total travel and operation cost, while the lower level is a transit network assignment model considering supply and demand uncertainties that influence passengers’ travel choice decisions. A heuristic algorithm is developed to solve the problem, and a numerical example is presented to illustrate the application. We get some important results: (1) a diversified fare structure considering uncertain weather’s impact is quite necessary; (2) when the value of time is at a high level, metro fare should be higher than bus fare; (3) the optimal metro and bus fare should be close under an extremely adverse weather condition; (4) fare structure could be quite different with varied value of time. Jiantong Zhang, Biyu Lv, Guichao Tian, and Wenchi Liu Copyright © 2014 Jiantong Zhang et al. All rights reserved. Least Squares Pure Imaginary Solution and Real Solution of the Quaternion Matrix Equation with the Least Norm Tue, 15 Apr 2014 12:30:03 +0000 http://www.hindawi.com/journals/jam/2014/857081/ Using the Kronecker product of matrices, the Moore-Penrose generalized inverse, and the complex representation of quaternion matrices, we derive the expressions of least squares solution with the least norm, least squares pure imaginary solution with the least norm, and least squares real solution with the least norm of the quaternion matrix equation , respectively. Shi-Fang Yuan Copyright © 2014 Shi-Fang Yuan. All rights reserved. Weak Projective Synchronization in Drive-Response Dynamical Networks with Time-Varying Delay and Parameter Mismatch Tue, 15 Apr 2014 12:19:26 +0000 http://www.hindawi.com/journals/jam/2014/356924/ This paper investigates the problem of projective synchronization in drive-response dynamical networks (DRDNs) with time-varying delay and parameter mismatch via impulsive control. Owing to projective factor and parameter mismatch, complete projective synchronization cannot be achieved. Therefore, a weak projective synchronization scheme is proposed to ensure that the DRDNs are in a state of synchronization with an error level. Based on the stability analysis of the impulsive functional differential equations, a general method of the weak projective synchronization with the error level is derived in DRDNs. Numerical simulations are provided to verify the correctness and effectiveness of the proposed method and results. Jiang Xu and Song Zheng Copyright © 2014 Jiang Xu and Song Zheng. All rights reserved. Semantic Consistency Checking in Building Ontology from Heterogeneous Sources Tue, 15 Apr 2014 10:41:04 +0000 http://www.hindawi.com/journals/jam/2014/181938/ Semantic collision is inevitable while building a domain ontology from heterogeneous data sources (semi-)automatically. Therefore, the semantic consistency is indispensable precondition for building a correct ontology. In this paper, a model-checking-based method is proposed to handle the semantic consistency problem with a kind of middle-model methodology, which could extract a domain ontology from structured and semistructured data sources semiautomatically. The method translates the middle model into the Kripke structure, and consistency assertions into CTL formulae, so a consistency checking problem is promoted to a global model checking. Moreover, the feasibility and correctness of the transformation is proved, and case studies are provided. Shihan Yang, Hongyan Tan, and Jinzhao Wu Copyright © 2014 Shihan Yang et al. All rights reserved. On the Numerical Solution of One-Dimensional Nonlinear Nonhomogeneous Burgers’ Equation Tue, 15 Apr 2014 09:55:05 +0000 http://www.hindawi.com/journals/jam/2014/598432/ The nonlinear Burgers’ equation is a simple form of Navier-Stocks equation. The nonlinear nature of Burgers’ equation has been exploited as a useful prototype differential equation for modeling many phenomena. This paper proposes two meshfree methods for solving the one-dimensional nonlinear nonhomogeneous Burgers’ equation. These methods are based on the multiquadric (MQ) quasi-interpolation operator and direct and indirect radial basis function networks (RBFNs) schemes. In the present schemes, the Taylors series expansion is used to discretize the temporal derivative and the quasi-interpolation is used to approximate the solution function and its spatial derivatives. In order to show the efficiency of the present methods, several experiments are considered. Our numerical solutions are compared with the analytical solutions as well as the results of other numerical schemes. Furthermore, the stability analysis of the methods is surveyed. It can be easily seen that the proposed methods are efficient, robust, and reliable for solving Burgers’ equation. Maryam Sarboland and Azim Aminataei Copyright © 2014 Maryam Sarboland and Azim Aminataei. All rights reserved. Analysis and Enhancement of a Password Authentication and Update Scheme Based on Elliptic Curve Cryptography Tue, 15 Apr 2014 09:52:30 +0000 http://www.hindawi.com/journals/jam/2014/247836/ Recently, a password authentication and update scheme has been presented by Islam and Biswas to remove the security weaknesses in Lin and Huang’s scheme. Unfortunately, He et al., Wang et al., and Li have found out that Islam and Biswas’ improvement was vulnerable to offline password guessing attack, stolen verifier attack, privilege insider attack, and denial of service attack. In this paper, we further analyze Islam and Biswas’ scheme and demonstrate that their scheme cannot resist password compromise impersonation attack. In order to remedy the weaknesses mentioned above, we propose an improved anonymous remote authentication scheme using smart card without using bilinear paring computation. In addition, the verifier tables are no longer existent, and the privacy of users could be protected better. Furthermore, our proposal not only inherits the advantages in Islam and Biswas’ scheme, but also provides more features, including preserving user anonymity, supporting offline password change, revocation, reregistration with the same identifier, and system update. Finally, we compare our enhancement with related works to illustrate that the improvement is more secure and robust, while maintaining low performance cost. Lili Wang Copyright © 2014 Lili Wang. All rights reserved. Energy-Efficient Probabilistic Routing Algorithm for Internet of Things Tue, 15 Apr 2014 07:13:11 +0000 http://www.hindawi.com/journals/jam/2014/213106/ In the future network with Internet of Things (IoT), each of the things communicates with the others and acquires information by itself. In distributed networks for IoT, the energy efficiency of the nodes is a key factor in the network performance. In this paper, we propose energy-efficient probabilistic routing (EEPR) algorithm, which controls the transmission of the routing request packets stochastically in order to increase the network lifetime and decrease the packet loss under the flooding algorithm. The proposed EEPR algorithm adopts energy-efficient probabilistic control by simultaneously using the residual energy of each node and ETX metric in the context of the typical AODV protocol. In the simulations, we verify that the proposed algorithm has longer network lifetime and consumes the residual energy of each node more evenly when compared with the typical AODV protocol. Sang-Hyun Park, Seungryong Cho, and Jung-Ryun Lee Copyright © 2014 Sang-Hyun Park et al. All rights reserved. A Novel Self-Adaptive Trust Region Algorithm for Unconstrained Optimization Tue, 15 Apr 2014 00:00:00 +0000 http://www.hindawi.com/journals/jam/2014/610612/ A new self-adaptive rule of trust region radius is introduced, which is given by a piecewise function on the ratio between the actual and predicted reductions of the objective function. A self-adaptive trust region method for unconstrained optimization problems is presented. The convergence properties of the method are established under reasonable assumptions. Preliminary numerical results show that the new method is significant and robust for solving unconstrained optimization problems. Yunlong Lu, Wenyu Li, Mingyuan Cao, and Yueting Yang Copyright © 2014 Yunlong Lu et al. All rights reserved. Exact Magnetothermoelastic Solution for a Hollow Sphere Subjected to Initial Stress, Rotation, and Magnetic Field Mon, 14 Apr 2014 13:17:50 +0000 http://www.hindawi.com/journals/jam/2014/920198/ We estimated an analytical solution of the displacement, stress, and temperature in a rotating isotropic homogeneous elastic medium hollow sphere subjected to periodic loading and magnetic field. The coupled theory of thermoelasticity is applied to determine an infinite velocity of heat propagation. The numerical calculations are carried out for the displacement, temperature, and stresses. The results obtained are displayed graphically to illustrate the effect of initial stress, rotation, and magnetic field which indicate to pronounce influence of rotation and magnetic field. S. M. Abo-Dahab, Nahed S. Hussein, and M. Al-Bokamy Copyright © 2014 S. M. Abo-Dahab et al. All rights reserved. Test Purpose Oriented I/O Conformance Test Selection with Colored Petri Nets Mon, 14 Apr 2014 13:17:48 +0000 http://www.hindawi.com/journals/jam/2014/645235/ This paper proposes an input-output conformance (IOCO) test selection method directed by test purpose model specified with colored Petri nets (CPN). Based on conformance testing oriented CPN models for specifying software functional behaviors and specific test purposes, respectively, feasible test cases are generated, guided by the CPN based IOCO relation, using synchronized model simulation with the proof of the soundness of test generation and the coverage towards test purposes. This test selection method integrates the merits the IOCO testing theory and the CPN modeling synergistically and is applied as a novel and applicable test selection method for actual testing practice of large-scale software systems. As the synchronized model simulation with two CPN models is irrespective of their model scale, the effectiveness and practicability of our test selection method are enhanced with scalability. Jing Liu, Xinming Ye, and Jiantao Zhou Copyright © 2014 Jing Liu et al. All rights reserved. Modeling and Optimization of Beam Pumping System Based on Intelligent Computing for Energy Saving Mon, 14 Apr 2014 13:10:13 +0000 http://www.hindawi.com/journals/jam/2014/317130/ Beam pumping system which is widely used in petroleum enterprises of China is one of the most energy-consuming equipment. It is difficult to be modeled and optimized due to its complication and nonlinearity. To address this issue, a novel intelligent computing based method is proposed in this paper. It firstly employs the general regression neural network (GRNN) algorithm to obtain the best model of the beam pumping system, and secondly searches the optimal operation parameters with improved strength Pareto evolutionary algorithm (SPEA2). The inputs of GRNN include the number of punching, the maximum load, the minimum load, the effective stroke, and the computational pump efficiency, while the outputs are the electric power consumption and the oil yield. Experimental results show that there is good overlap between model estimations and unseen data. Then sixty-one sets of optimum parameters are found based on the obtained model. Also, the results show that, under the optimum parameters, more than 5.34% oil yield is obtained and more than 3.75% of electric power consumption is saved. Xiaohua Gu, Taifu Li, Zhiqiang Liao, Liping Yang, and Ling Nie Copyright © 2014 Xiaohua Gu et al. All rights reserved. A Bio-Inspired QoS-Oriented Handover Model in Heterogeneous Wireless Networks Mon, 14 Apr 2014 09:57:42 +0000 http://www.hindawi.com/journals/jam/2014/920123/ We propose a bio-inspired model for making handover decision in heterogeneous wireless networks. It is based on an extended attractor selection model, which is biologically inspired by the self-adaptability and robustness of cellular response to the changes in dynamic environments. The goal of the proposed model is to guarantee multiple terminals’ satisfaction by meeting the QoS requirements of those terminals’ applications, and this model also attempts to ensure the fairness of network resources allocation, in the meanwhile, to enable the QoS-oriented handover decision adaptive to dynamic wireless environments. Some numerical simulations are preformed to validate our proposed bio-inspired model in terms of adaptive attractor selection in different noisy environments. And the results of some other simulations prove that the proposed handover scheme can adapt terminals’ network selection to the varying wireless environment and benefits the QoS of multiple terminal applications simultaneously and automatically. Furthermore, the comparative analysis also shows that the bio-inspired model outperforms the utility function based handover decision scheme in terms of ensuring a better QoS satisfaction and a better fairness of network resources allocation in dynamic heterogeneous wireless networks. Daxin Tian, Jianshan Zhou, Honggang Qi, Yingrong Lu, Yunpeng Wang, Jian Wang, and Anping He Copyright © 2014 Daxin Tian et al. All rights reserved. Application of EMD-Based SVD and SVM to Coal-Gangue Interface Detection Mon, 14 Apr 2014 08:58:02 +0000 http://www.hindawi.com/journals/jam/2014/283606/ Coal-gangue interface detection during top-coal caving mining is a challenging problem. This paper proposes a new vibration signal analysis approach to detecting the coal-gangue interface based on singular value decomposition (SVD) techniques and support vector machines (SVMs). Due to the nonstationary characteristics in vibration signals of the tail boom support of the longwall mining machine in this complicated environment, the empirical mode decomposition (EMD) is used to decompose the raw vibration signals into a number of intrinsic mode functions (IMFs) by which the initial feature vector matrices can be formed automatically. By applying the SVD algorithm to the initial feature vector matrices, the singular values of matrices can be obtained and used as the input feature vectors of SVMs classifier. The analysis results of vibration signals from the tail boom support of a longwall mining machine show that the method based on EMD, SVD, and SVM is effective for coal-gangue interface detection even when the number of samples is small. Wei Liu, Kai He, Qun Gao, and Cheng-yin Liu Copyright © 2014 Wei Liu et al. All rights reserved. Information Sharing and Channel Construction of Supply Chain under Asymmetric Demand Information Mon, 14 Apr 2014 07:25:13 +0000 http://www.hindawi.com/journals/jam/2014/107589/ Information sharing and marketing channel building have become an important problem of supply chain management theory and practice. The research of information sharing focused on traditional channel of supply chain between upstream and downstream enterprises; however, the research ignores the behavior of information sharing with potential entrants and composite structure characteristics about traditional marketing channel with the direct channel. This paper uses the model to research the effects brought about sharing demand information with potential entrants and building marketing channel, which reveals information sharing and channel building mechanism in the supply chain. The study found that the five-force model of Porter regards potential entrants only as a threat that is one-sided. When the channel competitiveness meets certain conditions, manufacturer and retailer will share demand information with potential entrants. Building composite marketing channel is the manufacturer's absolute dominant strategy. Channel construction will increase the entry barriers for potential entrants and weaken the effect of double marginalization; meanwhile, the performance of supply chain will be augmented. Guangdong Wu, Qingshan Kong, Jian-gang Shi, Hamid Reza Karimi, and Wei Zhang Copyright © 2014 Guangdong Wu et al. All rights reserved.