Mathematical Problems in Engineering https://www.hindawi.com The latest articles from Hindawi © 2017 , Hindawi Limited . All rights reserved. Optimization and Customer Utilities under Dynamic Lead Time Quotation in an Type Base Stock System Thu, 25 May 2017 08:04:21 +0000 http://www.hindawi.com/journals/mpe/2017/5805404/ In a manufacturing and inventory system, information on production and order lead time helps consumers’ decision whether they receive finished products or not by considering their own impatience on waiting time. In Savaşaneril et al. (2010), the optimal dynamic lead time quotation policy in a one-stage production and inventory system with a base stock policy for maximizing the system’s profit and its properties are discussed. In this system, each arriving customer decides whether he/she enters the system based on the quoted lead time informed by the system. On the other hand, the customer’s utility may be small under the optimal quoted lead time policy because the actual lead time may be longer than the quoted lead time. We use a utility function with respect to benefit of receiving products and waiting time and propose several kinds of heuristic lead time quotation policies. These are compared with optimal policies with respect to both profits and customer’s utilities. Through numerical examples some kinds of heuristic policies have better expected utilities of customers than the optimal quoted lead time policy maximizing system’s profits. Koichi Nakade and Hiroki Niwa Copyright © 2017 Koichi Nakade and Hiroki Niwa. All rights reserved. A Comprehensive Presentation of the Turbulent Plane Jet Theory with Passive Scalar Thu, 25 May 2017 06:18:18 +0000 http://www.hindawi.com/journals/mpe/2017/4369895/ We present a unified vision of the existing theoretical models for the turbulent plane jet, leading to new analytical profiles for scalar concentration and turbulent quantities, including a complete turbulent kinetic energy budget. Integrals of the budget terms are also computed. The present model is split into two variants. Both compare fairly well with referenced experimental data. D. Violeau Copyright © 2017 D. Violeau. All rights reserved. Risky Multicriteria Group Decision Making Based on Cloud Prospect Theory and Regret Feedback Thu, 25 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/9646303/ The assessment of risky linguistic variables has significant applications in multiattribute group decision problems. This paper focuses on risky multicriteria group decision making using linguistic variable assessment and proposes a new model which considers various and differential psychological behavior and the ambiguity of linguistic variable assessment across multicriteria risks. Based on the cloud prospect value assessment, this paper proposes a cloud prospect value aggregation method and consensus degree measurement. An improved feedback adjustment mechanism based on regret theory is employed as the consistency model, which complements prospect theory. The three theoretical methods together constitute the core elements of the proposed CPD (cloud prospect value consensus degree decision) model. The feasibility and validity of the new decision making model are demonstrated with a numerical example, and feedback performance was compared with conventional direct feedback. The proposed CPD approach satisfies given consistency threshold of 0.95 and 0.98 after three and four feedback loops, respectively. Compared to the proposed CPD method, direct feedback approach needs seven and ten feedback loops under the same threshold, respectively, which shows that the proposed model increases efficiency and accuracy of group decision making and significantly reduces time cost. Yan Song, Hao Yao, Shuang Yao, Donghua Yu, and Yan Shen Copyright © 2017 Yan Song et al. All rights reserved. Analysis of the Hydroelastic Performance of Very Large Floating Structures Based on Multimodules Beam Theory Wed, 24 May 2017 09:25:53 +0000 http://www.hindawi.com/journals/mpe/2017/6482527/ The hydroelastic behavior of very large floating structures (VLFSs) is investigated based on the proposed multimodules beam theory (MBT). To carry out the analysis, the VLFS is first divided into multiple submodules that are connected through their gravity center by a spatial beam with specific stiffness. The external force exerted on the submodules includes the wave hydrodynamic force as well as the beam bending force due to the relative displacements of different submodules. The wave hydrodynamic force is computed based on three-dimensional potential theory. The beam bending force is expressed in the form of a stiffness matrix. The motion response defined at the gravity center of the submodules is solved by the multibody hydrodynamic control equations; then both the displacement and the structure bending moment of the VLFS are determined from the stiffness matrix equations. To account for the moving point mass effects, the proposed method is extended to the time domain based on impulse response function (IRF) theory. The method is verified by comparison with existing results. Detailed results through the displacement and bending moment of the VLFS are provided to show the influence of the number of the submodules and the influence of the moving point mass. Jin Xu, Yonggang Sun, Zhifu Li, Xiantao Zhang, and Da Lu Copyright © 2017 Jin Xu et al. All rights reserved. Prediction Model of Mechanical Extending Limits in Horizontal Drilling and Design Methods of Tubular Strings to Improve Limits Wed, 24 May 2017 08:50:09 +0000 http://www.hindawi.com/journals/mpe/2017/2968231/ Mechanical extending limit in horizontal drilling means the maximum horizontal extending length of a horizontal well under certain ground and down-hole mechanical constraint conditions. Around this concept, the constrained optimization model of mechanical extending limits is built and simplified analytical results for pick-up and slack-off operations are deduced. The horizontal extending limits for kinds of tubular strings under different drilling parameters are calculated and drawn. To improve extending limits, an optimal design model of drill strings is built and applied to a case study. The results indicate that horizontal extending limits are underestimated a lot when the effects of friction force on critical helical buckling loads are neglected. Horizontal extending limits firstly increase and tend to stable values with vertical depths. Horizontal extending limits increase faster but finally become smaller with the increase of horizontal pushing forces for tubular strings of smaller modulus-weight ratio. Sliding slack-off is the main limit operation and high axial friction is the main constraint factor constraining horizontal extending limits. A sophisticated installation of multiple tubular strings can greatly inhibit helical buckling and increase horizontal extending limits. The optimal design model is called only once to obtain design results, which greatly increases the calculation efficiency. Wenjun Huang, Deli Gao, and Yinghua Liu Copyright © 2017 Wenjun Huang et al. All rights reserved. Modelling and Analysis on Emergency Evacuation from Metro Stations Wed, 24 May 2017 08:29:00 +0000 http://www.hindawi.com/journals/mpe/2017/2623684/ Efficient calculation on passenger evacuation performances under emergencies is crucial to the planning, design, and operation of metro systems as it is closely related to the safety of human lives. Four calculation methodologies including the China CDM, NFPA 130, control volume, and M/G/c/c models and a multiagent-based simulation approach are employed to calculate the evacuation time under a given number of evacuees in different application backgrounds by investigating impact factors and strategies of evacuation as well as moving speed of evacuees. The M/G/c/c model and multiagent-based simulation approach are also used to identify the bottleneck of evacuation in metro stations. A case study for the Xizhimen metro station in Beijing is carried out to validate the effectiveness of these methodologies to planners, designers, and operators in practice. The results show that the former two methodologies are concise quantitative methods while the latter ones are more capable of assessing the whole process and details of evacuation. Shaokuan Chen, Yue Di, Shuang Liu, and Baoshan Wang Copyright © 2017 Shaokuan Chen et al. All rights reserved. Stochastic Interest Model Based on Compound Poisson Process and Applications in Actuarial Science Wed, 24 May 2017 07:23:16 +0000 http://www.hindawi.com/journals/mpe/2017/3472319/ Considering stochastic behavior of interest rates in financial market, we construct a new class of interest models based on compound Poisson process. Different from the references, this paper describes the randomness of interest rates by modeling the force of interest with Poisson random jumps directly. To solve the problem in calculation of accumulated interest force function, one important integral technique is employed. And a conception called the critical value is introduced to investigate the validity condition of this new model. We also discuss actuarial present values of several life annuities under this new interest model. Simulations are done to illustrate the theoretical results and the effect of parameters in interest model on actuarial present values is also analyzed. Shilong Li, Chuancun Yin, Xia Zhao, and Hongshuai Dai Copyright © 2017 Shilong Li et al. All rights reserved. Effects of Compound -Distributed Sea Clutter on Angle Measurement of Wideband Monopulse Radar Wed, 24 May 2017 07:11:15 +0000 http://www.hindawi.com/journals/mpe/2017/2081718/ The effects of compound K-distributed sea clutter on angle measurement of wideband monopulse radar are investigated in this paper. We apply the conditional probability density function (pdf) of monopulse ratio (MR) error to analyze these effects. Based on the angle measurement procedure of the wideband monopulse radar, this conditional pdf is first deduced in detail for the case of compound -distributed sea clutter plus noise. Herein, the spatial correlation of the texture components for each channel clutter and the correlation of the texture components between the sum and difference channel clutters are considered, and two extreme situations for each of them are tackled. Referring to the measured sea clutter data, angle measurement performances in various K-distributed sea clutter plus noise circumstances are simulated, and the effects of compound K-distributed sea clutter on angle measurement are discussed. Hong Zhu, Yujian Pan, Weiwei Wu, Ning Tai, and Naichang Yuan Copyright © 2017 Hong Zhu et al. All rights reserved. Finite-Time Output Feedback Controller Based on Observer for the Time-Varying Delayed Systems: A Moore-Penrose Inverse Approach Wed, 24 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/2808094/ This study proposes a novel variable structure control (VSC) for the mismatched uncertain systems with unknown time-varying delay. The novel VSC includes the finite-time convergence sliding mode, invariance property, asymptotic stability, and measured output only. A necessary and sufficient condition guaranteeing the existence of sliding surface is given. A novel lemma is established to deal with the control design problem for a wider class of time-delay systems. A suitable reduced-order observer (ROO) is constructed to estimate unmeasured state variables of the systems. A novel finite-time output feedback controller (FTOFC) is investigated, which is based on the ROO tool and the Moore-Penrose inverse technique. Moreover, with the help of this lemma and the proposed FTOFC, restrictions on most existing works are also eliminated. In addition, an asymptotic stability analysis is implemented by means of the feasibility of the linear matrix inequalities (LMIs) and given desirable sliding mode dynamics. Finally, a MATLAB simulation result on a numerical example is performed to show the effectiveness and advantage of the proposed method. Cong-Trang Nguyen and Yao-Wen Tsai Copyright © 2017 Cong-Trang Nguyen and Yao-Wen Tsai. All rights reserved. Skin Friction Reduction Characteristics of Nonsmooth Surfaces Inspired by the Shapes of Barchan Dunes Wed, 24 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/6212605/ A new type of nonsmooth surface inspired by the shape of barchan dunes has been proposed and is intended to reduce skin friction, a major cause of overall drag. Simulations were carried out to obtain skin friction reduction characteristics for the nonsmooth surface using the commercial computational fluid dynamics software Fluent. A realizable -ε model was employed to assess the influence of the nonsmooth structure on turbulent flow and velocity fields. The numerical simulation results showed that the new nonsmooth surface possesses the desired skin friction reduction effect and that the maximum skin friction reduction percentage reached 33.63% at a fluid speed of 30 m/s. Various aspects of the skin friction reduction mechanism were discussed, including the distribution of velocity vectors and shear stress contours and the variations in boundary layer thickness. The accuracy of the flow field for the nonsmooth unit was further verified by particle image velocimetry test results. The new bionic nonsmooth surface, which exceeds the limitations of existing nonsmooth bionic structures, can effectively reduce skin friction and should provide insights into engineering applications in the future. Xiao-wen Song, Ming-xiao Zhang, and Peng-zhe Lin Copyright © 2017 Xiao-wen Song et al. All rights reserved. Modeling and Simulation Study of Designer’s Bidirectional Behavior of Task Selection in Open Source Design Process Wed, 24 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/6738139/ Open source design (OSD) is an emerging mode of product design. In OSD process, how to select right tasks directly influences the efficiency and quality of task completion, hence impacting the whole evolution process of OSD. In this paper, designer’s bidirectional behavior of task selection integrating passive selection based on website recommendation and autonomous selection is modeled. First, the model of passive selection behavior by website recommendation is proposed with application of collaborative filtering algorithm, based on a three-dimensional matrix including information of design agents, tasks, and skills; second, the model of autonomous selection behavior is described in consideration of factors such as skill and incentive; third, the model of bidirectional selection behavior is described integrating the aforementioned two selection algorithms. At last, contrast simulation analysis of bidirectional selection, passive selection based on website recommendation, and autonomous selection is proposed with ANOVA, and results show that task selection behavior has significant effect on OSD evolution process and that bidirectional selection behavior is more effective to shorten evolution cycle according to the experiment settings. In addition, the simulation study testifies the model of bidirectional selection by describing the task selection process of OSD in microperspective. Shuo Zhang and Yingzi Li Copyright © 2017 Shuo Zhang and Yingzi Li. All rights reserved. Analysis Bending Solutions of Clamped Rectangular Thick Plate Wed, 24 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/7539276/ The bending solutions of rectangular thick plate with all edges clamped and supported were investigated in this study. The basic governing equations used for analysis are based on Mindlin’s higher-order shear deformation plate theory. Using a new function, the three coupled governing equations have been modified to independent partial differential equations that can be solved separately. These equations are coded in terms of deflection of the plate and the mentioned functions. By solving these decoupled equations, the analytic solutions of rectangular thick plate with all edges clamped and supported have been derived. The proposed method eliminates the complicated derivation for calculating coefficients and addresses the solution to problems directly. Moreover, numerical comparison shows the correctness and accuracy of the results. Yang Zhong and Qian Xu Copyright © 2017 Yang Zhong and Qian Xu. All rights reserved. Robust L-Isomap with a Novel Landmark Selection Method Wed, 24 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/3930957/ Isomap is a widely used nonlinear method for dimensionality reduction. Landmark-Isomap (L-Isomap) has been proposed to improve the scalability of Isomap. In this paper, we focus on two important issues that were not taken into account in L-Isomap, landmark point selection and topological stability. At first, we present a novel landmark point selection method. It first uses a greedy strategy to select some points as landmark candidates and then removes the candidate points that are neighbours of other candidates. The remaining candidate points are the landmark points. The selection method can promote the computation efficiency without sacrificing accuracy. For the topological stability, we define edge density for each edge in the neighbourhood graph. According to the geometrical characteristic of the short-circuit edges, we provide a method to eliminate the short-circuit edge without breaking the data integrity. The approach that integrates L-Isomap with these two improvements is referred to as Robust L-Isomap (RL-Isomap). The effective performance of RL-Isomap is confirmed through several numerical experiments. Hao Shi, Baoqun Yin, Yu Kang, Chao Shao, and Jie Gui Copyright © 2017 Hao Shi et al. All rights reserved. Time Optimal Control of a Thermoelastic System Wed, 24 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/6047670/ This paper considers the numerical approximation for the time optimal control problem of a thermoelastic system with some control and state constraints. By the Galerkin finite element method (FEM), the original problem is projected into a semidiscrete optimal control problem governed by a system of ordinary differential equations. Then the optimal time and control parameterization method is applied to reduce the original system to an optimal parameter selection problem, in which both the optimal time and control are taken as decision variables to be optimized. This problem can be solved as a nonlinear optimization problem by a hybrid algorithm consisting of chaotic particle swarm optimization (CPSO) and sequential quadratic programming (SQP) algorithm. The numerical simulations demonstrate the effectiveness of the proposed numerical approximation method. Qiyu Liu, Qunxiong Zhu, Zhiqiang Geng, and Longjin Lv Copyright © 2017 Qiyu Liu et al. All rights reserved. A Universal High-Performance Correlation Analysis Detection Model and Algorithm for Network Intrusion Detection System Tue, 23 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/8439706/ In big data era, the single detection techniques have already not met the demand of complex network attacks and advanced persistent threats, but there is no uniform standard to make different correlation analysis detection be performed efficiently and accurately. In this paper, we put forward a universal correlation analysis detection model and algorithm by introducing state transition diagram. Based on analyzing and comparing the current correlation detection modes, we formalize the correlation patterns and propose a framework according to data packet timing and behavior qualities and then design a new universal algorithm to implement the method. Finally, experiment, which sets up a lightweight intrusion detection system using KDD1999 dataset, shows that the correlation detection model and algorithm can improve the performance and guarantee high detection rates. Hongliang Zhu, Wenhan Liu, Maohua Sun, and Yang Xin Copyright © 2017 Hongliang Zhu et al. All rights reserved. Research on Ciphertext-Policy Attribute-Based Encryption with Attribute Level User Revocation in Cloud Storage Tue, 23 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/4070616/ Attribute-based encryption (ABE) scheme is more and more widely used in the cloud storage, which can achieve fine-grained access control. However, it is an important challenge to solve dynamic user and attribute revocation in the original scheme. In order to solve this problem, this paper proposes a ciphertext-policy ABE (CP-ABE) scheme which can achieve attribute level user attribution. In this scheme, if some attribute is revoked, then the ciphertext corresponding to this attribute will be updated so that only the individuals whose attributes meet the access control policy and have not been revoked will be able to carry out the key updating and decrypt the ciphertext successfully. This scheme is proved selective-structure secure based on the -Parallel Bilinear Diffie-Hellman Exponent (BDHE) assumption in the standard model. Finally, the performance analysis and experimental verification have been carried out in this paper, and the experimental results show that, compared with the existing revocation schemes, although our scheme increases the computational load of storage service provider (CSP) in order to achieve the attribute revocation, it does not need the participation of attribute authority (AA), which reduces the computational load of AA. Moreover, the user does not need any additional parameters to achieve the attribute revocation except for the private key, thus saving the storage space greatly. Guangbo Wang and Jianhua Wang Copyright © 2017 Guangbo Wang and Jianhua Wang. All rights reserved. T-S Fuzzy Modelling and Attitude Control for Hypersonic Gliding Vehicles Tue, 23 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/6574527/ This paper addresses the T-S fuzzy modelling and attitude control in three channels for hypersonic gliding vehicles (HGVs). First, the control-oriented affine nonlinear model has been established which is transformed from the reentry dynamics. Then, based on Taylor’s expansion approach and the fuzzy linearization approach, the homogeneous T-S local modelling technique for HGVs is proposed. Given the approximation accuracy and controller design complexity, appropriate fuzzy premise variables and operating points of interest are selected to construct the T-S homogeneous submodels. With so-called fuzzy blending, the original plant is transformed into the overall T-S fuzzy model with disturbance. By utilizing Lyapunov functional approach, a state feedback fuzzy controller has been designed based on relaxed linear matrix inequality (LMI) conditions to stable the original plants with a prescribed performance of disturbance. Finally, numerical simulations are performed to demonstrate the effectiveness of the proposed T-S fuzzy controller for the original attitude dynamics; the superiority of the designed T-S fuzzy controller compared with other local controllers based on the constructed fuzzy model is shown as well. Weidong Zhang, Xianlin Huang, and Xiao-Zhi Gao Copyright © 2017 Weidong Zhang et al. All rights reserved. Sliding Mode Control of Cable-Driven Redundancy Parallel Robot with 6 DOF Based on Cable-Length Sensor Feedback Tue, 23 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/1928673/ The sliding mode control of the cable-driven redundancy parallel robot with six degrees of freedom is studied based on the cable-length sensor feedback. Under the control scheme of task space coordinates, the cable length obtained by the cable-length sensor is used to solve the forward kinematics of the cable-driven redundancy parallel robot in real-time, which is treated as the feedback for the control system. First, the method of forward kinematics of the cable-driven redundancy parallel robot is proposed based on the tetrahedron method and Levenberg-Marquardt method. Then, an iterative initial value estimation method for the Levenberg-Marquardt method is proposed. Second, the sliding mode control method based on the exponential approach law is used to control the effector of the robot, and the influence of the sliding mode parameters on control performance is simulated. Finally, a six-degree-of-freedom position tracking experiment is carried out on the principle prototype of the cable-driven redundancy parallel robot. The experimental results show that the robot can accurately track the desired position in six directions, which indicates that the control method based on the cable-length sensor feedback for the cable-driven redundancy parallel robot is effective and feasible. Wei Lv, Limin Tao, and Zhengnan Ji Copyright © 2017 Wei Lv et al. All rights reserved. Reconstructed Error and Linear Representation Coefficients Restricted by -Minimization for Face Recognition under Different Illumination and Occlusion Mon, 22 May 2017 10:14:47 +0000 http://www.hindawi.com/journals/mpe/2017/1458412/ The problem of recognizing human faces from frontal views with varying illumination, occlusion, and disguise is a great challenge to pattern recognition. A general knowledge is that face patterns from an objective set sit on a linear subspace. On the proof of the knowledge, some methods use the linear combination to represent a sample in face recognition. In this paper, in order to get the more discriminant information of reconstruction error, we constrain both the linear combination coefficients and the reconstruction error by -minimization which is not apt to be disturbed by outliners. Then, through an equivalent transformation of the model, it is convenient to compute the parameters in a new underdetermined linear system. Next, we use an optimization method to get the approximate solution. As a result, the minimum reconstruction error has contained much valuable discriminating information. The gradient of this variable is measured to decide the final recognition. The experiments show that the recognition protocol based on the reconstruction error achieves high performance on available databases (Extended Yale B and AR Face database). Xuegang Wu, Bin Fang, Yuan Yan Tang, Xiaoping Zeng, and Changyuan Xing Copyright © 2017 Xuegang Wu et al. All rights reserved. K-Line Patterns’ Predictive Power Analysis Using the Methods of Similarity Match and Clustering Mon, 22 May 2017 09:51:00 +0000 http://www.hindawi.com/journals/mpe/2017/3096917/ Stock price prediction based on K-line patterns is the essence of candlestick technical analysis. However, there are some disputes on whether the K-line patterns have predictive power in academia. To help resolve the debate, this paper uses the data mining methods of pattern recognition, pattern clustering, and pattern knowledge mining to research the predictive power of K-line patterns. The similarity match model and nearest neighbor-clustering algorithm are proposed for solving the problem of similarity match and clustering of K-line series, respectively. The experiment includes testing the predictive power of the Three Inside Up pattern and Three Inside Down pattern with the testing dataset of the K-line series data of Shanghai 180 index component stocks over the latest 10 years. Experimental results show that the predictive power of a pattern varies a great deal for different shapes and each of the existing K-line patterns requires further classification based on the shape feature for improving the prediction performance. Lv Tao, Yongtao Hao, Hao Yijie, and Shen Chunfeng Copyright © 2017 Lv Tao et al. All rights reserved. A Modified Lotka–Volterra Model for Diffusion and Substitution of Multigeneration DRAM Processing Technologies Sun, 21 May 2017 08:03:43 +0000 http://www.hindawi.com/journals/mpe/2017/3038203/ We attempt to develop an effective forecasting model for the diffusion and substitution of multigeneration Dynamic Random Access Memory (DRAM) processing technologies. We consider market share data and propose a modified Lotka–Volterra model, in which an additional constraint on the summation of market share is introduced. The mean absolute error is used to measure the accuracy of our market share predictions. Market share data in DRAM industries from quarter one (Q1) of 2005 to 2013 Q4 is collected to validate the prediction accuracy. Our model significantly outperforms other benchmark forecasting models of both revenue and market share data, including the Bass and Lotka–Volterra models. Compared to prior studies on forecasting the diffusion and substitution of multigeneration technologies, our model has two new perspectives: () allowing undetermined number of multigeneration technologies and inconsecutive adoption of new technologies and () requiring less data for forecasting newborn technologies. Hui-Chih Hung, Yu-Chih Chiu, and Muh-Cherng Wu Copyright © 2017 Hui-Chih Hung et al. All rights reserved. Division of Area of Fixation Interest for Real Vehicle Driving Tests Sun, 21 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/3674374/ The area of interest (AOI) reflects the degree of attention of a driver while driving. The division of AOI is visual characteristic analysis required in both real vehicle tests and simulated driving scenarios. Some key eye tracking parameters and their transformations can only be obtained after the division of AOI. In this study, 9 experienced and 7 novice drivers participated in real vehicle driving tests. They were asked to drive along a freeway section and a highway section, wearing the Dikablis eye tracking device. On average, 8132 fixation points for each driver were extracted. After coordinate conversion, the MSAP (Mean Shift Affinity Propagation) method is proposed to classify the distribution of fixation points into a circle type and a rectangle type. Experienced drivers’ fixation behavior falls into the circle type, in which fixation points are concentrated. Novice drivers’ fixation points, which are decentralized, are illustrated in the rectangle type. In the clustering algorithm, the damping coefficient determines the algorithm convergence, and the deviation parameter mainly affects the number of clusters, where larger values generate more clusters. This study not only provides the cluster type and cluster counts, but also presents the borderlines for each cluster. The findings provide significant contribution to eye tracking research. Qian Xu, Tang-yi Guo, Fei Shao, and Xue-jiao Jiang Copyright © 2017 Qian Xu et al. All rights reserved. Inverse Kinematics of a 7R 6-DOF Robot with Nonspherical Wrist Based on Transformation into the 6R Robot Thu, 18 May 2017 08:40:28 +0000 http://www.hindawi.com/journals/mpe/2017/2074137/ The 7R 6-DOF robots with hollow nonspherical wrist have been proven more suitable for spray painting applications. However, the inverse kinematics of this kind of robot is still imperfect due to the coupling between position and orientation of the end-effector (EE). In this paper, a new and efficient algorithm for the inverse kinematics of a 7R 6-DOF robot is proposed. The proposed inverse kinematics algorithm is a two-step method. The geometry of the 7R 6-DOF robot is analyzed. A comparison between the 7R 6-DOF robot and the well-known equivalent 6R robot is made. Based on this comparison, a rational transformation between these two kinds of robots is constructed. Then the general inverse kinematics algorithm of the equivalent 6R robot is applied to calculate the approximate solutions of the 7R 6-DOF robot, in the first step. The Damped Least-Squares (DLS) method is employed to derive the exact solutions, in the second step. The accuracy and efficiency of the algorithm are tested on a 7R 6-DOF painting robot. The results show that the proposed algorithm is more advantageous in the case without an approximate solution, such as the initial point of a continuous trajectory. Xuhao Wang, Dawei Zhang, and Chen Zhao Copyright © 2017 Xuhao Wang et al. All rights reserved. A Combined Fault Diagnosis Method for Power Transformer in Big Data Environment Thu, 18 May 2017 06:59:57 +0000 http://www.hindawi.com/journals/mpe/2017/9670290/ The fault diagnosis method based on dissolved gas analysis (DGA) is of great significance to detect the potential faults of the transformer and improve the security of the power system. The DGA data of transformer in smart grid have the characteristics of large quantity, multiple types, and low value density. In view of DGA big data’s characteristics, the paper first proposes a new combined fault diagnosis method for transformer, in which a variety of fault diagnosis models are used to make a preliminary diagnosis, and then the support vector machine is used to make the second diagnosis. The method adopts the intelligent complementary and blending thought, which overcomes the shortcomings of single diagnosis model in transformer fault diagnosis, and improves the diagnostic accuracy and the scope of application of the model. Then, the training and deployment strategy of the combined diagnosis model is designed based on Storm and Spark platform, which provides a solution for the transformer fault diagnosis in big data environment. Yan Wang and Liguo Zhang Copyright © 2017 Yan Wang and Liguo Zhang. All rights reserved. Supply Chain Model with Stochastic Lead Time, Trade-Credit Financing, and Transportation Discounts Thu, 18 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/6465912/ This model extends a two-echelon supply chain model by considering the trade-credit policy, transportations discount to make a coordination mechanism between transportation discounts, trade-credit financing, number of shipments, quality improvement of products, and reduced setup cost in such a way that the total cost of the whole system can be reduced, where the supplier offers trade-credit-period to the buyer. For buyer, the backorder rate is considered as variable. There are two investments to reduce setup cost and to improve quality of products. The model assumes lead time-dependent backorder rate, where the lead time is stochastic in nature. By using the trade-credit policy, the model gives how the credit-period would be determined to achieve the win-win outcome. An iterative algorithm is designed to obtain the global optimum results. Numerical example and sensitivity analysis are given to illustrate the model. Sung Jun Kim and Biswajit Sarkar Copyright © 2017 Sung Jun Kim and Biswajit Sarkar. All rights reserved. Automatic Image Annotation Based on Particle Swarm Optimization and Support Vector Clustering Thu, 18 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/8493267/ With the progress of network technology, there are more and more digital images of the internet. But most images are not semantically marked, which makes it difficult to retrieve and use. In this paper, a new algorithm is proposed to automatically annotate images based on particle swarm optimization (PSO) and support vector clustering (SVC). The algorithm includes two stages: firstly, PSO algorithm is used to optimize SVC; secondly, the trained SVC algorithm is used to annotate the image automatically. In the experiment, three datasets are used to evaluate the algorithm, and the results show the effectiveness of the algorithm. Zhangang Hao, Hongwei Ge, and Tianpeng Gu Copyright © 2017 Zhangang Hao et al. All rights reserved. Robust Adaptive Neural Control of Morphing Aircraft with Prescribed Performance Wed, 17 May 2017 06:17:26 +0000 http://www.hindawi.com/journals/mpe/2017/1401427/ This study proposes a low-computational composite adaptive neural control scheme for the longitudinal dynamics of a swept-back wing aircraft subject to parameter uncertainties. To efficiently release the constraint often existing in conventional neural designs, whose closed-loop stability analysis always necessitates that neural networks (NNs) be confined in the active regions, a smooth switching function is presented to conquer this issue. By integrating minimal learning parameter (MLP) technique, prescribed performance control, and a kind of smooth switching strategy into back-stepping design, a new composite switching adaptive neural prescribed performance control scheme is proposed and a new type of adaptive laws is constructed for the altitude subsystem. Compared with previous neural control scheme for flight vehicle, the remarkable feature is that the proposed controller not only achieves the prescribed performance including transient and steady property but also addresses the constraint on NN. Two comparative simulations are presented to verify the effectiveness of the proposed controller. Zhonghua Wu, Jingchao Lu, Jingping Shi, Yang Liu, and Qing Zhou Copyright © 2017 Zhonghua Wu et al. All rights reserved. The Loading Control Strategy of the Mobile Dynamometer Vehicle Based on Neural Network PID Wed, 17 May 2017 00:00:00 +0000 http://www.hindawi.com/journals/mpe/2017/5658983/ To solve the problems of low loading precision, slow response speed, and poor adaptive ability of a mobile dynamometer in a tractor traction test, a PID control strategy based on a radial basis function neural network with self-learning and adaptive ability is proposed. The mathematical model of the loading system is established, the algorithm of adaptive control is described, and the loading control method is simulated with MATLAB software. The system, which uses the NN-PID (neural network PID) control strategy, is used to test a YTO-MF554 tractor. Then, the proposed control strategy is validated. Results show that when the traction increases from 0 to 10 kN, the response time of the test system is 1.5 s, the average traction force in the stability range is 10.13 kN, and the maximum relative error of traction force is 2.2%. This control strategy can improve the response speed and steady-state accuracy and enhance the adaptive ability of the mobile dynamometer vehicle loading system. This study provides a reference for designing the adaptive controller of the mobile dynamometer vehicle loading system. Xianghai Yan, Liyou Xu, and Yuan Wang Copyright © 2017 Xianghai Yan et al. All rights reserved. GIF Video Sentiment Detection Using Semantic Sequence Tue, 16 May 2017 09:36:13 +0000 http://www.hindawi.com/journals/mpe/2017/6863174/ With the development of social media, an increasing number of people use short videos in social media applications to express their opinions and sentiments. However, sentiment detection of short videos is a very challenging task because of the semantic gap problem and sequence based sentiment understanding problem. In this context, we propose a SentiPair Sequence based GIF video sentiment detection approach with two contributions. First, we propose a Synset Forest method to extract sentiment related semantic concepts from WordNet to build a robust SentiPair label set. This approach considers the semantic gap between label words and selects a robust label subset which is related to sentiment. Secondly, we propose a SentiPair Sequence based GIF video sentiment detection approach that learns the semantic sequence to understand the sentiment from GIF videos. Our experiment results on GSO-2016 (GIF Sentiment Ontology) data show that our approach not only outperforms four state-of-the-art classification methods but also shows better performance than the state-of-the-art middle level sentiment ontology features, Adjective Noun Pairs (ANPs). Dazhen Lin, Donglin Cao, Yanping Lv, and Zheng Cai Copyright © 2017 Dazhen Lin et al. All rights reserved. Effects of Variable Production Rate and Time-Dependent Holding Cost for Complementary Products in Supply Chain Model Tue, 16 May 2017 07:30:31 +0000 http://www.hindawi.com/journals/mpe/2017/2825103/ Recently, a major trend is going to redesign a production system by controlling or making variable the production rate within some fixed interval to maintain the optimal level. This strategy is more effective when the holding cost is time-dependent as it is interrelated with holding duration of products and rate of production. An effort is made to make a supply chain model (SCM) to show the joint effect of variable production rate and time-varying holding cost for specific type of complementary products, where those products are made by two different manufacturers and a common retailer makes them bundle and sells bundles to end customers. Demand of each product is specified by stochastic reservation prices with a known potential market size. Those players of the SCM are considered with unequal power. Stackelberg game approach is employed to obtain global optimum solution of the model. An illustrative numerical example, graphical representation, and managerial insights are given to illustrate the model. Results prove that variable production rate and time-dependent holding cost save more than existing literature. Mitali Sarkar, Sun Hur, and Biswajit Sarkar Copyright © 2017 Mitali Sarkar et al. All rights reserved.