Beifang University of Nationalities

Ningxia, China

Beifang University of Nationalities

Ningxia, China

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Mao J.,Beifang University of Nationalities
Optical and Quantum Electronics | Year: 2012

Remote sensing technique of lidar belongs to the category of weak signal extraction under strong background noise. For effectively reducing the noise of lidar return signal, a wavelet analysis method using local threshold value is employed. In the local threshold value wavelet method, different threshold values are used to quantify the high frequency coefficients of every decomposition layer. Both the numerical simulation signal contaminated by random noise of different standard deviation and the practical Mie lidar returns were adopted, and the comparisons among sliding-window method, global threshold method and local threshold method were performed for verifying the feasibility of the local threshold method. Experiment results show that the local threshold wavelet method is a useful de-noising method which shows better effects of noise reduction than other two methods. © Springer Science+Business Media, LLC 2011.


Wang L.,Shanghai University of Sport | Qi J.,Beifang University of Nationalities
Adapted Physical Activity Quarterly | Year: 2015

This study examined the behavioral beliefs of physical education (PE) teachers about teaching students with disabilities in their general PE (GPE) classes and to identify the factors that contribute to their beliefs. A total of 195 PE teachers from a region in eastern China were surveyed. Results of the Physical Educators’ Attitudes Toward Teaching Individuals With Disabilities-III survey indicate that although some teachers felt that including students with disabilities in GPE classes provides benefit for them, they were concerned about the practical difficulties of teaching students with disabilities in GPE classes, the lack of support, and the possible rejection of students with disabilities by their peers. Moreover, the behavioral beliefs of teachers vary according to the disability conditions of the students. Results show that there is no significant effect of demographic factors on the beliefs of PE teachers. Quality of experience predicts positive beliefs. The study has important implication for teacher training, provision of equipment, and support from teacher assistants. © 2015 Human Kinetics, Inc.


Yu G.,Beifang University of Nationalities
Journal of Convergence Information Technology | Year: 2012

By using estimation algorithm to solve multi-objective optimization, multi-objective estimation of distribution algorithm with simulated binary crossover (MEDA-SBC) is proposed. The new population is only generated by sampling method in MEDA. MEDA-SBC generates the new population with sampling method and simulated binary crossover, which is different from general multi-objective estimation of distribution algorithm. The offspring population is generated by selection strategy of NSGA-II. Number experiments compared with NSGA-II, SPEA2 and MEDA on six benchmark problems, the simulation results show the effectiveness of the proposed MEDA-SBC.


Yu G.,Beifang University of Nationalities
International Journal of Advancements in Computing Technology | Year: 2011

In this paper, an improved multi-objective differential evolution algorithm(IDEA) is proposed for multi-objective optimization problems. In IDEA, the select operator combines the advantages of DE with the mechanisms of Pareto-based ranking and distance density, besides, a randomly migration strategy is proposed. IDEA is implemented on four classical multi-objective problems, the simulation results indicate that the proposed IDEA efficiently achieves two goals of multi-objective optimization problems: find the solutions converse to the true Pareto-front and uniform spread along the front.


Rong R.,Beifang University of Nationalities
Proceedings of the 28th Chinese Control and Decision Conference, CCDC 2016 | Year: 2016

Hyperspectral remote sensing technology is applied to many fields because of its super-multiband, high resolution and vast information. Its classification technology is a research hotspot now. Abundant information is not utilized fully in traditional remote sensing image classification method; so many improved algorithms are disappeared in order to enhance efficiency, accuracy and intelligence. The hyperspectral remote sensing image processing flow is introduced. Merit, demerits and development tendency of classification method are clarified. © 2016 IEEE.


Qian Y.,Beifang University of Nationalities
Proceedings of the 28th Chinese Control and Decision Conference, CCDC 2016 | Year: 2016

This paper presents a kind of new variable step size algorithm in which the changing of step size is associated with error signal. The error signal is bigger during the initial working period of system, and step size is bigger too in order to satisfy the need for faster convergence of adaptive system, then the error signal and the step size is smaller too, so the system is always in a stable state of convergence. By adjusting the very only regulatory factor in the algorithm, the step size can be adjusted easily to meet the needs of different filtering. MATLAB results show that the convergence, stability and filtering effect of adaptive system when using this algorithm are superior to fixed step size. © 2016 IEEE.


Li Y.,Shaanxi Normal University | Ma Z.,Shaanxi Normal University | Ma Z.,Beifang University of Nationalities
IEEE Transactions on Fuzzy Systems | Year: 2015

We study generalized possibilistic computation tree logic (GPoCTL) model checking in this paper, which is an extension of possibilistic computation logic model checking introduced by Li et al. (2014). The system is modeled by generalized possibilistic Kripke structures, and the verifying property is specified by a GPoCTL formula. Based on generalized possibility measures and generalized necessity measures, the method of GPoCTL model checking is discussed, and the corresponding algorithm and its complexity are shown in detail. Furthermore, the comparison between possibilistic computation tree logic and GPoCTL is given. Finally, a thermostat example is given to illustrate the GPoCTL model-checking method. © 2015 IEEE.


Liang X.,Beifang University of Nationalities | Li X.,CAS Institute of Mechanics
Communications in Computational Physics | Year: 2015

In this paper, direct numerical simulation (DNS) is presented for spatially evolving turbulent boundary layer over an isothermal flat-plate at Mâž = 2.25,5,6,8. When Mâž = 8, two cases with the ratio of wall-to-reference temperature Tω/Tž = 1.9 and 10.03 are considered respectively. The wall temperature approaches recovery temperatures for other cases. The characteristics of compressible turbulent boundary layer (CTBL) affected by freestream Mach number and wall temperature are investigated. It focuses on assessing compressibility effects and the validity of Morkovin's hypothesis through computing and analyzing the mean velocity profile, turbulent intensity, the strong Reynolds analogy (SRA) and possibility density function of dilatation term. The results show that, when the wall temperature approaches recovery temperature, the effects of Mach number on compressibility is insignificant. As a result, the compressibility effect is very weak and the Morkovin's hypothesis is still valid for Mach number even up to 8. However, when Mach number equal to 8, the wall temperature effect on the compressibility is sensitive. In this case, when Tω/Tž = 1.9, the Morkovin's hypothesis is not fully valid. The validity of classical SRA depends on wall temperature directly. A new modified SRA is proposed to eliminate such negative factor in near wall region. Finally the effects of Mach number and wall temperature on streaks are also studied. © Global Science Press Limited 2015.


Bai J.,Beifang University of Nationalities
Jisuanji Jicheng Zhizao Xitong/Computer Integrated Manufacturing Systems, CIMS | Year: 2014

Aiming at the problem that the existing 3D Computer Aided Design (CAD) model retrieval algorithm was difficult to capture engineering semantics in components and satisfy the needs of design reuse, a novel approach of 3D CAD model similarity assessment based on extended feature tree was proposed. Through defining the design features interactively and establishing the relationships between these features automatically, the boundary representation of 3D CAD model was taken as the input to build the extended feature tree. The 3D CAD model was given by extending feature trees and geometric attributes of design features comprehensively, and the similarity evaluation between 3D CAD models was realized through an approximate tree matching algorithm and an adaptive weighting scheme. Theoretical analysis and experimental results showed that the method could quickly retrieve similar 3D CAD models, and the retrieval results could reflect the design semantics of the model and meet the needs of design reuse.


Xu J.,Beifang University of Nationalities
Key Engineering Materials | Year: 2016

Ultrafine drug powders have higher bioavaibability than the larger signed particles. Ultrafine powders of clarithromycin were produced by anti-solvent recrystallization with the acetone - water solvent systems. The effects of volume ratio of clarithromycin acetone solution to anti-solvent, stirring speed, precipitation temperature and precipitation time on the preparation process were investigated. The results show that ultrafine powders can be yielded and well-controlled under the following optimal conditions: the volume ratio of clarithromycin acetone solution to anti-solvent 1:10, stirring speed 900 r/min, precipitation temperature 20°C, and precipitation time 10 min. The ultrafine powders with the rod-shape and the mean diameter of 1.8 μm with the narrow distribution were successfully obtained. The yield of drug powders is more than 83%. The powders were analyzed with FT-IR and metalloscope. The purity of drug powders is more than 98%, according with Chinese Pharmacopoeia. The operation of the experiment was very simple, and the powders were separated easily. © 2016 Trans Tech Publications, Switzerland.

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