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Combining Diffusion and Grey Models Based on Evolutionary Optimization algorithms to Forecast Motherboard Shipments

MATHEMATICAL PROBLEMS IN ENGINEERING 2012年第1期2012卷 1-10页

作者： Wang, Fu-Kwun Hsiao, Yu-Yao Chang, Ku-Kuang Natl Taiwan Univ Sci & Technol Dept Ind Management Taipei 106 Taiwan Natl Taiwan Univ Sci & Technol Grad Inst Management Taipei 106 Taiwan Takming Univ Sci & Technol Dept Logist Management Taipei 114 Taiwan

It is important for executives to predict the future trends. Otherwise, their companies cannot make profitable decisions and investments. The Bass diffusion model can describe the empirical adoption curve for new products and technological innovations. The Grey model provides short-term forecasts using four data points. This study develops a combined model based on the rolling Grey model (RGM) and the Bass diffusion model to forecast motherboard shipments. In addition, we investigate evolutionary optimization algorithms to determine the optimal parameters. Our results indicate that the combined model using a hybrid algorithm outperforms other methods for the fitting and forecasting processes in terms of mean absolute percentage error.

关键词： algorithm research TECHNOLOGICAL innovations MATHEMATICAL optimization DIFFUSION MOTHERBOARDS (Microcomputers) ERROR analysis (Mathematics)

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Approximate Analytic and Numerical Solutions to Lane-Emden Equation via Fuzzy Modeling Method

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MATHEMATICAL PROBLEMS IN ENGINEERING 2012年第1期2012卷 1-15页

作者： Wang, De-Gang Song, Wen-Yan Shi, Peng Karimi, Hamid Reza Univ Adelaide Sch Elect & Elect Engn Adelaide SA 5005 Australia Dalian Univ Technol Sch Control Sci & Engn Dalian 116024 Peoples R China Dongbei Univ Finance & Econ Dept Quantitat Econ Dalian 116025 Peoples R China Victoria Univ Sch Sci & Engn Melbourne Vic 8001 Australia Univ Agder Fac Sci & Technol Dept Engn N-4898 Grimstad Norway

A novel algorithm, called variable weight fuzzy marginal linearization (VWFML) method, is proposed. This method can supply approximate analytic and numerical solutions to Lane-Emden equations. And it is easy to be implemented and extended for solving other nonlinear differential equations. Numerical examples are included to demonstrate the validity and applicability of the developed technique.

关键词： LINEAR systems algorithm research NUMERICAL solutions to equations NONLINEAR difference equations DIFFERENCE equations

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A Numerical Study of Low-Thrust Limited Power Trajectories between Coplanar Circular Orbits in an Inverse-Square Force Field

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MATHEMATICAL PROBLEMS IN ENGINEERING 2012年第1期2012卷 1-24页

作者： Fernandes, Sandro da Silva Silveira Filho, Carlos Roberto Golfetto, Wander Almodovar Inst Tecnol Aeronaut Dept Matemat BR-12228900 Sao Jose Dos Campos SP Brazil EMBRAER SA Div Ensaio Voo BR-12227901 Sao Jose Dos Campos SP Brazil Dept Ciencia & Tecnol Aeroespacial Subdept Tecn BR-12228900 Sao Jose Dos Campos SP Brazil

A numerical study of optimal low-thrust limited power trajectories for simple transfer (no rendezvous) between circular coplanar orbits in an inverse-square force field is performed by two different classes of algorithms in optimization of trajectories. This study is carried out by means of a direct method based on gradient techniques and by an indirect method based on the second variation theory. The direct approach of the trajectory optimization problem combines the main positive characteristics of two well-known direct methods in optimization of trajectories: the steepest-descent (first-order gradient) method and a direct second variation (second-order gradient) method. On the other hand, the indirect approach of the trajectory optimization problem involves two different algorithms of the well-known neighboring extremals method. Several radius ratios and transfer durations are considered, and the fuel consumption is taken as the performance criterion. For small-amplitude transfers, the results are compared to the ones provided by a linear analytical theory.

关键词： algorithm research SPACE trajectories TRAJECTORY optimization ORBITAL mechanics LINEAR models (Statistics)

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A Multiplicative Noise Removal Approach Based on Partial Differential Equation Model

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MATHEMATICAL PROBLEMS IN ENGINEERING 2012年第1期2012卷 1-14页

作者： Chen, Bo Cai, Jin-Lin Chen, Wen-Sheng Li, Yan Shenzhen Univ Coll Math & Computat Sci Shenzhen 518060 Peoples R China

Multiplicative noise, also known as speckle noise, is signal dependent and difficult to remove. Based on a fourth-order PDE model, this paper proposes a novel approach to remove the multiplicative noise on images. In practice, Fourier transform and logarithm strategy are utilized on the noisy image to convert the convolutional noise into additive noise, so that the noise can be removed by using the traditional additive noise removal algorithm in frequency domain. For noise removal, a new fourth-order PDE model is developed, which avoids the blocky effects produced by second-order PDE model and attains better edge-preserve ability. The performance of the proposed method has been evaluated on the images with both additive and multiplicative noise. Compared with some traditional methods, experimental results show that the proposed method obtains superior performance on different PSNR values and visual quality.

关键词： PARTIAL differential equations NOISE control -- research algorithm research DIFFRACTION patterns FOURIER transforms

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Compressive genomics

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NATURE BIOTECHNOLOGY 2012年第7期30卷 627-630页

作者： Loh, Po-Ru Baym, Michael Berger, Bonnie MIT Dept Math & Comp Sci Cambridge MA 02139 USA MIT Artificial Intelligence Lab Cambridge MA 02139 USA Harvard Univ Sch Med Dept Syst Biol Boston MA USA

algorithms that compute directly on compressed genomic data allow analyses to keep pace with data generation.

关键词： GENOMICS GENETIC databases GENOMES algorithm research COMPUTERS in genetics

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The Application of Fuzzy Theory in Automatic Checking over Subjective Examination

The Application of Fuzzy Theory in Automatic Checking over S...

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2nd International Conference on Mechanical Engineering and Green Manufacturing (MEGM 2012)

作者： Gao, Shengyu Weinan Normal Univ Coll Math & Informat Sci Weinan 714000 Peoples R China

ISBN: (纸本)9783037853771

Having already carried on on-line examination under the network environment several years of history, regardless which kind examines it is,the problems is divided into objective and subjective. It have been very mature to Automatically grade examination papers in the objective by database technique For automatic checking over subjective examination, its procedure involves some restriction theory and technique development,such as artificial intelligence, natural language comprehension and mode identification etc., So far, there is no accepted *** paper put forward to the research direction of the algorithm in automatic checking over subjective examination by analyzing the present condition for grading examination papers.

关键词： Subjective problems Automatic marking Fuzzy mathematics algorithm research

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SOMO-m Optimization algorithm with Multiple Winners

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DISCRETE DYNAMICS IN NATURE AND SOCIETY 2012年第unknown期2012卷 1-13页

作者： Wu, Wei Khan, Atlas Dalian Univ Technol Dept Appl Math Dalian 116024 Peoples R China

Self-organizing map (SOM) neural networks have been widely applied in information sciences. In particular, Su and Zhao proposes in (2009) an SOM-based optimization (SOMO) algorithm in order to find a wining neuron, through a competitive learning process, that stands for the minimum of an objective function. In this paper, we generalize the SOM-based optimization (SOMO) algorithm to so-called SOMO-m algorithm with m winning neurons. Numerical experiments show that, for m > 1, SOMO-m algorithm converges faster than SOM-based optimization (SOMO) algorithm when used for finding the minimum of functions. More importantly, SOMO-m algorithm with m >= 2 can be used to find two or more minimums simultaneously in a single learning iteration process, while the original SOM-based optimization (SOMO) algorithm has to fulfil the same task much less efficiently by restarting the learning iteration process twice or more times.

关键词： research in information science MATHEMATICAL optimization research NEURONS algorithm research ITERATIVE methods (Mathematics)

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A Multiswarm Optimizer for Distributed Decision Making in Virtual Enterprise Risk Management

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DISCRETE DYNAMICS IN NATURE AND SOCIETY 2012年第unknown期2012卷 1-24页

作者： Shao, Yichuan Yao, Xingjia Tian, Liwei Chen, Hanning Chinese Acad Sci Shenyang Inst Automat Shenyang 110016 Peoples R China Shenyang Univ Coll Informat Sci & Engn Shenyang 110044 Peoples R China Shenyang Univ Technol Sch New Energy Engn Shenyang 110036 Peoples R China Shenyang Univ Sci & Technol Agcy Shenyang 110036 Peoples R China

We develop an optimization model for risk management in a virtual enterprise environment based on a novel multiswarm particle swarm optimizer called (PSO)-O-2. The main idea of (PSO)-O-2 is to extend the single population PSO to the interacting multiswarms model by constructing hierarchical interaction topology and enhanced dynamical update equations. With the hierarchical interaction topology, a suitable diversity in the whole population can be maintained. At the same time, the enhanced dynamical update rule significantly speeds up the multiswarm to converge to the global optimum. With five mathematical benchmark functions, (PSO)-O-2 is proved to have considerable potential for solving complex optimization problems. (PSO)-O-2 is then applied to risk management in a virtual enterprise environment. Simulation results demonstrate that the (PSO)-O-2 algorithm is more feasible and efficient than the PSO algorithm in solving this real-world problem.

关键词： MATHEMATICAL optimization research SWARM intelligence SIMULATION methods & models algorithm research STOCHASTIC convergence

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Convergence Study of Minimizing the Nonconvex Total Delay Using the Lane-Based Optimization Method for Signal-Controlled Junctions

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DISCRETE DYNAMICS IN NATURE AND SOCIETY 2012年第unknown期2012卷 1-14页

作者： Wong, C. K. Lee, Y. Y. City Univ Hong Kong Dept Civil & Architectural Engn Kowloon Hong Kong Peoples R China

This paper presents a 2D convergence density criterion for minimizing the total junction delay at isolated junctions in the lane-based optimization framework. The lane-based method integrates the design of lane markings and signal settings for traffic movements in a unified framework. The problem of delay minimization is formulated as a Binary Mix Integer Non Linear Program (BMINLP). A cutting plane algorithm can be applied to solve this difficult BMINLP problem by adding hyperplanes sequentially until sufficient numbers of planes are created in the form of solution constraints to replicate the original nonlinear surface in the solution space. A set of constraints is set up to ensure the feasibility and safety of the resultant optimized lane markings and signal settings. The main difficulty to solve this high-dimension nonlinear nonconvex delay minimization problem using cutting plane algorithm is the requirement of substantial computational efforts to reach a good-quality solution while approximating the nonlinear solution space. A new stopping criterion is proposed by monitoring a 2D convergence density to obtain a converged solution. A numerical example is given to demonstrate the effectiveness of the proposed methodology. The cutting-plane algorithm producing an effective signal design will become more computationally attractive with adopting the proposed stopping criterion.

关键词： STOCHASTIC convergence MATHEMATICAL optimization research NONLINEAR systems INTEGER programming algorithm research

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Numerical Treatment of the Model for HIV Infection of CD4⁺T Cells by Using Multistep Laplace Adomian Decomposition Method

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DISCRETE DYNAMICS IN NATURE AND SOCIETY 2012年第unknown期2012卷 1-11页

作者： Dogan, Nurettin Gazi Univ Fac Technol Dept Comp Engn TR-06500 Ankara Turkey

A new method for approximate analytic series solution called multistep Laplace Adomian Decomposition Method (MLADM) has been proposed for solving the model for HIV infection of CD4(+) T cells. The proposed method is modification of the classical Laplace Adomian Decomposition Method (LADM) with multistep approach. Fourth-order Runge-Kutta method (RK4) is used to evaluate the effectiveness of the proposed algorithm. When we do not know the exact solution of a given problem, generally we use the RK4 method for comparison since it is widely used and accepted. Comparison of the results with RK4 method is confirmed that MLADM performs with very high accuracy. Results show that MLADM is a very promising method for obtaining approximate solutions to the model for HIV infection of CD4(+) T cells. Some plots and tables are presented to show the reliability and simplicity of the methods. All computations have been made with the aid of a computer code written in Mathematica 7.

关键词： APPROXIMATION theory DECOMPOSITION (Mathematics) HIV infections research algorithm research T cells

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