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Journal of Systems Engineering and Electronics 2008年第5期19卷 996-1002页

作者： zhou Deyun zhou feng Coll. of Electronic Communication Northwestern Polytechnical Univ. Xi'an 710072 P. R. China

Under the complicated electromagnetism circumstance, the model of data fusion control and guidance of surface-to-air missile weapon systems is established. Such ways and theories as Elman-NN, radar tracking and filter＇s data fusion net based on the group method for data-processing （GMRDF） are applied to constructing the model of data fusion. The highly reliable state estimation of the tracking targets and the improvement in accuracy of control and guidance are obtained. The purpose is optimization design of data fusion control and guidance of surface-to-air missile weapon systems and improving the fighting effectiveness of surface-to-air missile weapon systems.

关键词： surface-to-air missile fusion neural net GMDH control and guidance.

A REMARK ON DUALITY FOR THE SUM OF CONVEX FUNCTIONS IN GENERAL BANACH SPACES

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Chinese Annals of Mathematics,Series B 1998年第3期19卷 249-254页

作者： zhou feng E China Normal Univ Dept Math Shanghai 200062 Peoples R China

The author gives a new proof of Attouch Brezis′ theorem concerned with the duality for the sum of convex functions in general Banach spaces, and gives also some sufficient conditions for the difference of two close... 详细信息

关键词： Conjugate convex function Asymptotic cone Infimal convolution

Investigation of electropolishing characteristics of tungsten in ecofriendly sodium hydroxide aqueous solution

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Advances in Manufacturing 2020年第3期8卷 265-278页

作者： Wei Han feng-zhou Fang Centre of Micro/Nano manufacturing Technology(MNMTDublin) University College DublinDublin 4Ireland State Key Laboratory of Precision Measuring Technology and Instruments Centre of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072People’s Republic of China

In this study,an eco-friendly electrolyte for electropolishing tungsten and the minimum material removal depth on the electropolished tungsten surface are investigated using an electrochemical etching *** a concentrated acid electrolyte,the polarization curve and current density transient are *** a NaOH electrolyte,the effects of interelectrode gap and electrolyte concentration on electropolishing are *** differences in electropolishing characteristics are compared among different electrolyte *** are etched on the electropolished tungsten surface to determine the minimum material removal depth on the tungsten *** results indicate the color effect due to a change in the thickness of the oxide film on the tungsten surface after electropolishing with a concentrated acid *** surface roughness decreases with the interelectrode gap width owing to the increased current density when using the NaOH ***,the electropolishing effect is less prominent with a significantly smaller gap because the generated bubbles are unable to escape from the narrow working gap in time.A material removal depth of less than 10 nm is achieved on the tungsten surface in an area of diameter 300 lm,using the electrochemical etching method.

关键词： Electropolishing NaOH solution Surface roughness Tungsten Etching

Crystallization Behavior of Anatase Films in Applied Electric Field Heating Process

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Journal of Rare Earths 2006年第z1期24卷 122-124页

作者： zhou feng Liang Kaiming Electromechanical and Materials Engineering College Dalian Maritime University Dalian 116026 China Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

In this research the TiO2 thin films were prepared by sol-gel dip coating. The crystallization of the films in the applied electric field heating process was thoroughly studied by many technique, differential thermal analysis (DTA), Raman spectroscopy and atomic force microscope (AFM). Furthermore the phase formation, microstructure and photo-catalytic activity of TiO2 film were studied under the condition of an electric field heating-treatment. It is found that the existence of applied electric field promotes the phase transformation from anatase to rutile. Studies on photo-catalytic degradation show that the photo-catalytic activity of TiO2 thin films in an applied electric field is higher.

关键词： crystallization electric field anatase

Optimal tool design in micro-milling of difficult-to-machine materials

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Advances in Manufacturing 2023年第2期11卷 222-247页

作者： Lorcan O'Toole feng-zhou Fang Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin 4Ireland State Key Laboratory of Precision Measuring Technology and Instruments Laboratory of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin300072People's Republic of China

The limitations of significant tool wear and tool breakage of commercially available fluted micro-end mill tools often lead to ineffective and inefficient manufacturing,while surface quality and geometric dimensions remain unacceptably *** is especially true for machining of difficult-to-machine(DTM)materials,such as super alloys and *** conventional fluted micro-tool designs are generally down scaled from the macro-milling tool ***,simply scaling such designs from the macro to micro domain leads to inherent design flaws,such as poor tool rigidity,poor tool strength and weak cutting edges,ultimately ending in tool ***,in this article a design process is first established to determine optimal micro-end mill tool designs for machining some typical DTM materials commonly used in manufacturing orthopaedic implants and micro-feature *** design process focuses on achieving robust stiffness and mechanical strength to reduce tool wear,avoid tool chipping and tool breakage in order to efficiently machine very hard ***,static stress and deflection finite element analysis(FEA)is carried out to identify stiffness and rigidity of the tool design in relation to the maximum deformations,as well as the Von Mises stress distribution at the cutting edge of the designed *** analysis and further optimisation of the FEA results,a verified optimum tool design is established for micro-milling DTM *** experimental study is then carried out to compare the optimum tool design to commercial tools,in regards to cutting forces,tool wear and surface quality.

关键词： Precision machining Micro-milling Difficult-to-machine(DTM) Tool wear Micro-tool design Surface quality

Sub-harmonicity,monotonicity formula and finite Morse index solutions of an elliptic equation with negative exponent

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Science China Mathematics 2015年第11期58卷 2301-2316页

作者： GUO ZongMing zhou feng Department of Mathematics Henan Normal University Center for PDEs and Department of Mathematics East China Normal University

A monotonicity formula for stable solutions to a class of weighted semilinear elliptic equations with ＂negative exponent＂ is established. It is well known that such a monotonieity formula plays an essential role in the study of finite Morse index solutions of equations with ＂positive exponent＂. Unlike the positive exponent case, we will see that both the monotonicity formula and the sub-harmonicity play crucial roles in classifying positive finite Morse index solutions to the equations with negative exponent and obtaining sharp results for their asymptotic behaviors.

关键词： sub-harmonicity monotonicity formula singular nonlinearity finite Morse index solutions

Significant photocatalytic enhancement in methylene blue degradation of Bi2WO6 photocatalysts via graphene hybridization

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Journal of Advanced Ceramics 2012年第1期1卷 72-78页

作者： feng zhou Yongfa ZHU Department of Materials Science and Engineering Dalian Maritime UniversityDalian 116026China Department of Chemistry Tsinghua UniversityBeijing 100084China

The hybridization of graphene with Bi_(2)WO_(6)photocatalysts was employed to enhance the photocatalytic *** photocatalytic activity enhancements were dependent on the amount of graphene and it was found that the optimal hybridized amount of graphene was about 1.5 wt%,which was close to the monolayer dispersing of graphene on Bi_(2)WO_(6)*** to four times of the photocatalytic activity was enhanced by the hybridization of graphene,compared with that of pristine Bi_(2)WO_(6).The enhancement mechanism of the photocatalytic activity was attributed to the higher separation efficiency and the inhibition of recombination of photoinduced electron-hole *** electronic interaction was verified by the photoelectrochemical measurements.

关键词： powders-chemical preparation carbon nanocomposites photocatalyst

A high precision visual localization sensor and its working methodology for an indoor mobile robot

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Frontiers of Information Technology & Electronic Engineering 2016年第4期17卷 365-374页

作者： feng-yu zhou Xian-feng YUAN Yang YANG Zhi-fei JIANG Chen-lei zhou School of Control Science and Engineering Shandong University School of Information Science and Engineering Shandong University

To overcome the shortcomings of existing robot localization sensors, such as low accuracy and poor robustness, a high precision visual localization system based on infrared-reflective artificial markers is designed and illustrated in detail in this paper. First, the hardware system of the localization sensor is developed. Secondly, we design a novel kind of infrared-reflective artificial marker whose characteristics can be extracted by the acquisition and processing of the infrared image. In addition, a confidence calculation method for marker identification is proposed to obtain the probabilistic localization results. Finally, the autonomous localization of the robot is achieved by calculating the relative pose relation between the robot and the artificial marker based on the perspective-3-point(P3P) visual localization algorithm. Numerous experiments and practical applications show that the designed localization sensor system is immune to the interferences of the illumination and observation angle changes. The precision of the sensor is ±1.94 cm for position localization and ±1.64° for angle localization. Therefore, it satisfies perfectly the requirements of localization precision for an indoor mobile robot.

关键词： Mobile robot Localization sensor Visual localization Infrared-reflective marker Embedded system

Selected-Mapping Peak-to-Average Power Reduction Method with Orthogonal Pilot Sequences in Underwater Acoustic OFDM System Without Side Information

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Chinese Journal of Electronics 2021年第1期30卷 160-163页

作者： QIAO Gang XING Siyu zhou feng Acoustic Science and Technology Laboratory Harbin Engineering University Key Laboratory of Marine Information Acquisition and Security (Harbin Engineering University) Ministry of Industry and Information Technology College of Underwater Acoustic Engineering Harbin Engineering University

A novel Selected-mapping(SLM) Peak-to-average power ratio(PAPR) reduction scheme requires no Side information(SI) in Underwater acoustic(UWA)OFDM system is proposed. In the proposed scheme,every distinct phase sequence is represented by a unique Orthogonal comb pilot sequence(OPS), and the orthogonal properties of the OPSs are used to distinguish the index of phase sequences at the receiver. Therefore, the proposed scheme does not need to reserve bits for transmitting SI,so that the data rate can be raised. Simulation results show that the PAPR reduction performance has almost 0.5 d B gains comparing to the Conventional SLM(C-SLM)scheme and the Bit error ratio(BER) performance is approximately the same as the SLM scheme with perfect SI. Field experimental results also demonstrate that the proposed scheme can differentiate phase sequences,therefore significantly enhance the quality of the UWA OFDM communication system.

关键词： 0.5dB gains OFDM modulation noise figure 0.5 dB Bit error ratio performance orthogonal pilot sequences orthogonal properties peak-to-average power reduction method C-SLM distinct phase sequence novel Selected-mapping phase sequences error statistics channel estimation UWA OFDM communication system unique Orthogonal comb pilot sequence Conventional SLM scheme perfect SI PAPR reduction performance Peak-to-average power ratio reduction scheme underwater acoustic communication underwater acoustic OFDM system

Amendment on the strain measurement of thin-walled human skull shell as intracranial pressure changes

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Journal of University of Science and Technology Beijing 2008年第2期15卷 202-208页

作者： Xianfang Yue Li Wang feng zhou School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China

The human skull, composed of tabula extema, tabula intema, and a porous diploe sandwiched in between, is deformed with changing intracranial pressure （ICP）. Because the human skull＇s thickness is only 6 mm, it is simplified as a thin-walled shell. The objective of this article is to analyze the strain of the thin-wailed shell by the stress-strain calculation of a human skull with changing ICP. Under the same loading conditions, using finite element analysis （FEA）, the strains of the human skull were calculated and the results were compared with the measurements of the simulative experiment in vitro. It is demonstrated that the strain of the thin-walled shell is totally measured by pasting the one-way strain foils on the exterior surface of the shell with suitable amendment for data. The amendment scope of the measured strain values of the thin-walled shell is from 13.04% to 22.22%.

关键词： human skull thin-wailed shell strain composite structure intracranial pressure finite element