Beijing, China

Beijing Union University

www.buu.edu.cn
Beijing, China

The Beijing Union University is a municipal university administered by the Beijing government of China. In order to facilitate the municipal development, BUU was established in the 1980s, incorporating vocational schools and taking over some of the satellite campuses affiliated to universities including Peking University, Tsinghua University, Renmin University, Beijing Foreign Studies University, Beijing International Studies University, etc. Wikipedia.

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Bian T.,Beijing Union University
Optics Communications | Year: 2017

All-dielectric slab waveguide filling the core with metamaterials of extreme anisotropy realizes the light transport being confined in a subdiffraction region with substantial energy concentration. The extreme anisotropy makes the evanescent waves in the claddings decay faster and the guided mode tightly localized in the core. Furthermore, the cutoff width can be decoupled from the group velocity of the mode, it can reach zero in the limit of extreme anisotropy but still sustain considerable group velocity. We analyze technically realizable cases and conclude that our work can contribute to improvements of various electromagnetic devices, from visible to microwave frequency regions. © 2017 Elsevier B.V.


Zhao J.-M.,Beijing Union University
Proceedings - 2016 8th International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2016 | Year: 2016

The uniform boundedness with respect to part of the retarded functional differential system variables is studied. The obtained result in this work utilize Lyapunov functions to determine the uniform boundedness of solutions of the Nonlinear retarded system. The result for the partial boundedness develop some theorems on uniform boundedness of ordinary differential system. An example is presented which demonstrates the result and gives insight into the new boundedness conditions. © 2016 IEEE.


Huang C.-E.,Beijing Union University | Li D.,Tsinghua University | Xue Y.,Tsinghua University
Control Engineering Practice | Year: 2013

A new control solution based on a unique active disturbance rejection control (ADRC) paradigm is proposed for the ALSTOM gasifier control problem. In the new control method, the disturbances, including unknown dynamics and external disturbances to the system, are treated as an augmented state that is estimated and then eliminated in real-time. A first-order ADRC scheme for the ALSTOM gasifier is designed. The simulation results show that the new control method is superior to the PI solution by Simm and Xue in terms of the integral of the absolute error of gas pressure disturbance tests at 0% load, the no-overshoot peak value of the gas temperature and the short time for the bed mass to return to the set point during a ramping test, and the ability to reject large coal quality disturbances. © 2012 Elsevier Ltd.


Wang Y.-P.,Beijing Union University
Research Journal of Applied Sciences, Engineering and Technology | Year: 2013

In order to conquer the premature convergence problem and lower the cost of computing of the basic Ant Colony Algorithm (ACA), we present an adaptive ant colony algorithm, named AACA, coupled with a Pareto Local Search (PLS) algorithm and apply to the Vehicle Routing Problem (VRP) and Capacitated VRP (CVRP). By using the information entropy, the algorithm adjusts the pheromone updating strategy adaptively. Experiments on various aspectsof the algorithm and computational results for some benchmark problems are reported. We compare our approach with some classic, powerful meta-heuristics and show that the proposed approach can obtain the better quality of the solutions. © Maxwell Scientific Organization, 2013.


We study the application of a kind of non-monotone line search's technique in conjugate gradient method. At present, most of the study of conjugate gradient methods are using Wolfe's monotone line search, by constructing the condition of Zoutendijk, we can get the conclusion that it's convergence by using reduction to absurdity. Here we study the global convergence of conjugate gradient methods with Armijo-type line search, the thought of proof wasn't using the method above mentioned.


InVO4/TiO2 nanocomposites were synthesized via a sol-gel process, and their microstructure and morphology were characterized by XRD and FESEM. XRD analysis indicated that incorporation of InVO4 with low content (In:Ti mole ratio of 1:200) could not change the crystallinity of anatase TiO2. The photocatalytic activity of anatase TiO2 increased for more than 2 folds by incorporating small amount of InVO4 into TiO2. The MB degradation rate kapp increased from 1.147×10-2 to 1.75×10-2 min-1 while the added Cr(IV) concentration was 5mg/L. The results indicated that simultaneous removal of aqueous Cr(IV) ions and organic compounds was feasible in the photocataltyic reactions under sunlight irradiation. © (2013) Trans Tech Publications, Switzerland.


Particle swarm optimization (PSO) is an evolutionary metaheuristic inspired by the flocking behavior of birds, which has successfully been used to solve several kinds of problems. In this paper, we refer to capacitated vehicle routing problem (CVRP) as the object to research distribution routing optimistic problem within transportation and logistics. An improved discrete particle swarm optimization (DPSO), a variant of PSO, combined with iterated local search (ILS) method is proposed. During the search process, the improved algorithm can adaptively adjust flying time of particles with the evolutionary generations and ILS ensures that the particles escaped from the local minimum. The experimental results for partial benchmark problems showed that the better results can be obtained by the method. © 2011 Published by Elsevier Ltd.


Zhang N.,Beijing Union University
Applied Mathematics and Information Sciences | Year: 2012

In communication network, WDM optical backbone network has become the primary long-distance options. In this paper, the structure of WDM optical networks are analyzed, the add-drop system in the architecture of WDM optical networks is discussed. In order to improve network efficiency, we analyzed the characteristics of network routing, and proposed a new routing design method. In communication network, a good routing is very important for network operation. Routing technologies manage the flow of data between network segments in optical communication network. In addition, we also discussed the WDM optical network switching technology.


In order to promote inventory management level, against the existing problem of spare parts management currently, the spare parts inventory management system of an enterprise engaged in casting and mechanical operations was studied. First, the simulation software Flexsim was used to model the original system. Then for the purpose of optimizing the system, ABC classification was proposed. According to the comparison of simulation results before and after optimization, optimized model can effectively improve the efficiency of inventory management. This can provide the reference of spare parts management for the other companies. © (2013) Trans Tech Publications, Switzerland.


Fang J.,Beijing Union University
Advances in Intelligent and Soft Computing | Year: 2012

This paper introduces a machine vision system for Chinese chess-playing robots which is usually regarded as a form of recreation. The machine vision system with two color cameras takes simultaneously two images of a chessboard and round pieces on the chessboard from different angles (views). Firstly, original images are handled by a series of image processing operations such as color conversion, binarization and denoise. Secondly, a hierarchical Hough transform algorithm was taken to detect lines and circles in the binarized image. Circles with reasonable radii nearly centered on the crossings of chessboard will be considered as pieces on the chessboard and its corresponding Chinese character inside the circle would be recognized based on BP neural network and ring intersection points. The 3D coordinates of pieces can be calculated through computation and then transformed to coordinates expressed by row and column. Finally, results of image processing and pattern recognition procedures will be sent to robot control system to manipulate end-effector of a robot to move round pieces from one place to another desired. Experimental results reveal that the designed machine vision system in this paper can work well with higher reliability. © 2012 Springer-Verlag GmbH Berlin Heidelberg.

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