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Face Feature Selection and Recognition Using Separability Criterion and Binary Particle Swarm Optimization Algorithm

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Chinese Journal of Electronics 2014年第2期23卷 361-365页

作者： yin Hongtao fu Ping SUN Zhen Automatic Test and Control Institute Harbin Institute of Technology

Discrete cosine transform(DCT) is an effective method to extract proper features for face recognition. Discrete cosine transform can only map the resource data to another data field instead of compress *** to select the DCT coefficients that are most effective for classification is an important problem. This paper proposes a novel method to search the best discriminant combination of DCT coefficients. A feature selection algorithm according to the separability criterion is used to preselect the DCT coefficients, and then follows a search algorithm based on binary particle swarm optimization and support vector machine to find an optimal combination of the DCT coefficient. The performance of the algorithm is assessed by computing the recognition rate and the number of selected features on ORL database and Cropped Yale database.

关键词： Separability criterion Binary particle swarm optimization Support vector machine Face recognition Feature selection

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期 80-87页

作者： Fang-Qian Wang yin Zhang Wei-Wei Wang Mei-Qian fu Hong-Bing Mo Wei-Dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

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Nonlinear Numerical Analysis of Vortex-Induced Vibration of A Three-Dimensional Deepwater Steep Wave Riser with Large Deformation Features

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China Ocean Engineering 2022年第4期36卷 601-613页

作者： CHENG Yong SONG fu-kai LI ming-xin School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

The cross-flow(CF)vortex-induced vibration(VIV)of a deepwater steep wave riser(SWR)subjected to uniform or shear flow loads is investigated *** model is based on a three-dimensional(3D)nonlinear elastic rod theory coupled with a wake oscillator *** this numerical simulation,the nonlinear motion equations of the riser with large deformation features are established in a global coordinate system to avoid the transformation between global and local coordinate systems,and are discretized with the time-domain finite element method(FEM).A wakeoscillator model is employed to study the vortex shedding,and the lift force generated by the wake flow is described in a van der Pol equation.A Newmark-βiterative scheme is used to solve their coupling equation for the VIV response of the *** developed model is validated against the existing experimental results for the VIV response of the top-tension riser(TTR).Then,the numerical simulations are executed to determine VIV characteristics of the *** effects of both flow velocity and the spanwise length of the flow field on the drag coefficient in the inline(IL)direction and the lift coefficient in the CF direction are investigated *** results indicate that compared with TTR,the low frequency and multi-modal vibration are the main components of the SWR due to the large deformation and flexible *** shear flow,the multi-frequency resonance dominates the VIV response of the SWR,especially at the hang-off segment.

关键词： steep wave riser vortex-induced vibration time domain simulation nonlinear finite element wake oscillator

Clinical study on the treatment of liver fibrosis due to hepatitis B by IFN-α1 and traditional medicine preparation

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World Journal of Gastroenterology 1999年第3期5卷 267-269页

作者： CHENG ming-Liang WU Ya-Yun HUANG Ke-fu LUO Tian-Yong DING Yi-Shen LU yin-yin LIU RenCaiand Wu Jun ming-Liang Cheng Ya-Yun Wu Tian-Yong Luo Yi-Shen Ding Yin-Yin Lu Jun Wu Department of Infectious Diseases Affiliated Hospital Guiyang Medical College Guiyang 550004 Guizhou Province China Ke-fu Huang Central Hospital of the Fifth Engineering Bureau of Railway Ministry Ren-Cai Liu Hospital of Bijie County Guizhou Province China ming-Liang Cheng male born on January 17 1959 in Guiyang Guizhou Province graduated from Guiyang Medical College as B.S. in 1982. Professor of Infectious Diseases specialized in hepatitis and hepatofibrosis having 38 papers and books published.

INTRODUCTIONIn China, liver fibrosis in most patients resulted from the viruses of hepatitis B. Both anti-virus and anti-fibrosis should be considered in designing a program for the treatment of liver fibrosis. Therefore, 40 cases of liver fibrosis due to hepatitis B were treated by using IFN-α1 and traditional medicinal preparations from February 1994 to April 1996. Good curative effect was achieved.

关键词： Clinical study on the treatment of liver fibrosis due to hepatitis B by IFN West and traditional medicine preparation

Experimental and Theoretical Study on the Self-Weight Penetration Velocity of Suction Anchor Foundations in Sand

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China Ocean Engineering 2023年第5期37卷 863-875页

作者： SUN Kai MA Hui-huan WANG fu-ming School of Civil Engineering Sun Yat-Sen University&Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Key Laboratory of Oceanic Civil Engineering Guangzhou 510275China

The application of the wellhead suction anchor in the second production test of natural gas hydrates(NGHs)in the South China Sea(SCS)was met with *** design incorporates a central conductor guide pipe,which distinguishes it from traditional suction ***,this addition resulted in a relatively high penetration resistance and a shallower penetration depth at the self-weight penetration *** mitigate this issue,the current study proposes an optimized design where the end of the suction foundation is *** installation characteristics of the traditional suction foundation and new suction foundation during self-weight penetration into sand are studied through laboratory tests and theoretical *** flat and sharpened bottom shapes are considered in the traditional and new suction *** effects of the initial penetration velocity on the initial penetration depth and soil plug and impact cavity characteristics are systematically *** results show that the self-weight penetration depth of the foundation with a sharpened bottom is 44.5%deeper than that of the foundation with a flat *** are cavities around the foundation at the self-weight penetration stage,and the penetration depth is overestimated by 15%-30%.Finally,a model for predicting the penetration depth of the new suction foundation is proposed.

关键词： suction foundation self-weight penetration penetration velocity soil plug sharpened bottom

Size effects on process performance and product quality in progressive microforming of shafted gears revealed by experiment and numerical modeling

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Advances in Manufacturing 2023年第1期11卷 1-20页

作者： Jun-Yuan Zheng Hui Liu ming-Wang fu Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China Research Institute for Advanced Manufacturing The Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China

As one of the indispensable actuating components in micro-systems,the shafted microgear is in great production *** is a manufacturing process to produce microgears to meet the *** to the small geometrical size,there are uncertain process performance and product quality issues in this production *** this study,the shafted microgears were fabricated in two different scaling factors with four grain sizes using a progressively extrusion-blanking *** explore the unknown of the process,grain-based modeling was proposed and employed to simulate the entire forming *** results show that when the grains are large,the anisotropy of single grains has an obvious size effect on the forming behavior and process performance;and the produced geometries and surface quality are worsened;and the deformation load is *** deformation zones were identified in the microstructures with different hardness and distributions of stress and *** simulation by using the proposed model successfully predicted the formation of zones and revealed the inhomogeneous deformation in the forming *** undesirable geometries of microgears including material unfilling,burr and inclination were observed on the shaft and teeth of gear,and the inclination size is increased obviously with grain *** avoid the formation of inclination and material unfilling,the punch was redesigned,and a die insert was added to constraint the bottom surface of the gear *** new products had then the better forming quality.

关键词： Microforming Microprocess performance Microforming quality Size effect affected deformation behavior Die design optimization

Environmental factors controlling soil warming and wetting during 2000-2020 in permafrost and non-permafrost regions across the Qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第2期15卷 285-296页

作者： Guo-An yin Jing LUO fu-Jun NIU ming-Hao LIU Ze-Yong GAO Tian-Chun DONG Wei-Heng NI State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co. Ltd.Xining 810000China University of Chinese Academy of Sciences Beijing 100049China

The Qinghai-Tibet Plateau(QTP)has experienced rapid environmental changes,including climate warming and wetting,since the *** environmental changes significantly impact the shallow soil hydrothermal conditions,which have key roles in land-atmosphere feedback and ecosystem ***,the spatial variations and responses of soil hydrothermal conditions to environmental changes over the QTP with permafrost(PF)and seasonal frost(SF)remain *** this study,we investigated the spatial variations in soil temperature(ST)and soil moisture(SM)changes over the QTP from 2000 to 2020 using 99 in-situ sites with observations at 4 depths(i.e.10,40,100 and 200 cm).The main environmental controlling factors were further identified using a calibrated statistical *** showed that significant(pming occurred at multiple soil layers during 2000-2020 with a wide variation(i.e.0.033-0.039℃ per year on average),whereas the warming rates at PF sites were two times greater than those at SF *** addition,the soil wetting rate was high over the SF region,whereas the soil wetting rate was low over the PF *** from air temperature,changes in thawing degree days and solar radiation(Srad)contributed most to soil warming in the PF region,whereas changes in rainfall,Srad and evaporation(EVA)have been identified as the key factors in the SF *** for soil wetting,changes in snowfall,freezing degree days and vegetation have noticeable nonlinear effects over the PF region,whereas changes in EVA,Srad and rainfall highlighted distinct linear and nonlinear effects in the SF *** findings enhance our understanding of the hydrothermal impacts of future environmental changes over the QTP.

关键词： Warming amd wetting Soil hydrothermal change Factor Permafrost Seasonal frost

Investigation Into Vibration Characteristic in Vibrothermography

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Photonic Sensors 2019年第2期9卷 108-114页

作者： yin LI Anbo ming Ruimin ZHANG Wei ZHANG Rocket Force University of Engineering Xi'an 710025China High-tech Institute Fan Gong-ting South Street on the 12thQingzhou 262550China

Vibration characteristic plays an important role in vibrothermography, which directly affects the heating during the test. In this work, involving all the contacts in the vibrothermography, the "double-mass-thiree-spring" model is established to explore the vibration characteristic. The obtained results show that ultrasonic gun vibrates at fundamental frequency (FF), while the specimen vibrates at multi-frequencies including FF, 2FF, 3FF, and 4FF, which is validated through experimental investigation results. Additionally, the model proposed in this work reveals a high order harmonics in the vibrothermography test and makes the specimen conduct the steady vibration, which indicates that the model is closer to the practical equipment and can ensure the heating efficiency induced by vibration of specimen to improve the detection capability.

关键词： Vibrothermography vibration characteristic “double-mass-three-spring” model

On parametric approach of aerial robots' visual navigation

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Journal of Systems Engineering and Electronics 2008年第5期19卷 1010-1016页

作者： Zhou Yu Huang Xianlin Jie ming yin Hang Harbin Inst. of Technology Harbin 150001 P. R. China

In aerial robots＇ visual navigation, it is essential yet very difficult to detect the attitude and position of the robots operated in real time. By introducing a new parametric model, the problem can be reduced from almost unmanageable to be partly solved, though not fully, as per the requirement. In this parametric approach, a multi-scale least square method is formulated first. By propagating as well as improving the parameters down from layer to layer of the image pyramid, a new global feature line can then be detected to parameterize the attitude of the robots. furthermore, this approach paves the way for segmenting the image into distinct parts, which can be realized by deploying a Bayesian classifier on the picture cell level. Comparison with the Hough transform based method in terms of robustness and precision shows that this multi-scale least square algorithm is considerably more robust to noises. Some discussions are also given.

关键词： parametric model aerial robots visual navigation multi-scale least square.