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Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm

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Chinese Physics B 2012年第1期21卷 558-565页

作者： Zu Yun-Xiao zhou jie School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm is proposed, and a fitness function is provided. Simulations are conducted using the adaptive niche immune genetic algo- rithm, the simulated annealing algorithm, the quantum genetic algorithm and the simple genetic algorithm, respectively. The results show that the adaptive niche immune genetic algorithm performs better than the other three algorithms in terms of the multi-user cognitive radio network resource allocation, and has quick convergence speed and strong global searching capability, which effectively reduces the system power consumption and bit error rate.

关键词： cognitive radio networks niche genetic algorithm King map resource allocation

Additive-multiplicative Hazards Model for Case-Cohort Studies with Multiple Disease Outcomes

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 183-192页

作者： Jun-e LIU jie zhou School of Statistics and Management Shanghai University of Finance and Economics School of Management Huaibei Normal University School of Mathematics Capital Normal University

Case-cohort design is an efficient and economical design to study risk factors for diseases with expensive measurements, especially when the disease rate is low. When several diseases are of interest, multiple case-cohort design studies may be conducted using the same subcohort. To study the association between risk factors and each disease occurrence or death, we consider a general additive-multiplicative hazards model for case-cohort designs with multiple disease outcomes. We present an estimation procedure for the regression parameters of the additive-multiplicative hazards model, and show that the proposed estimator is consistent and asymptotically normal. Large sample approximation works well in finite sample studies in simulation. Finally, we apply the proposed method to a real data example for illustration.

关键词： case-cohort studies additive-multiplicative model marginal hazards model multiple disease out-comes

Regularity and Compactness of Stationary Map-Varifold Pairs

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Chinese Annals of Mathematics,Series B 2023年第6期44卷 929-944页

作者： Jiayu LI jie zhou Chaona ZHU School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China School of Mathematical Sciences Capital Normal UniversityBeijing 100148China School of Mathematics and Statistics Ningbo UniversityNingbo 315211ZhejiangChina

The authors introduce the conception of stationary map-varifold pairs and prove a compactness *** applications,they analyse the asymptotic structure of the pseudo tangent map of stationary harmonic *** stationary pair,they also get a strong convergence criterion about the map part and introduce the stratification of the singular set.

关键词： Stationary map-varifold pairs Regularity Compactness

Analysis and Optimization on Factors Affecting Forming Quality of Half Axle Gears Warm Precision Forging

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Chinese Journal of Mechanical Engineering 2010年第1期23卷 110-114页

作者： WANG Menghan CHEN Xihou zhou jie College of Material Science and Engineering Chongqing University Chongqing 400044 China School of Electronic Information and Automation Chongqing University of Technology Chongqing 400050 China

Half axle gears is produced by precision forging popularly because of the advantages in minimum machining allowances, lower material consumption and good service properties. But the forming quality of precision forging is difficult to control. Many simulations and analysis of precision forging process were taken by previous researchers. But no concrete method is proposed to evaluate and optimize the forming quality of half axel gears. The primary purpose of this work is improving the forming quality of half axel gears by analyzing and optimizing the affected factors of forming quality. The enclosed-die warm forging process of half axle gears was developed, and a new type of die-set used on double action hydraulic press was brought forward. The main influential factors of precision forming quality were analyzed after the forming process had been simulated by using finite element method（FEM）. These factors include die structure, web thickness and web position. A method used to evaluate the forming quality was established, which investigated the maximal forming load, the metal filling rate and the material damage factor. The FEM simulations of half axle gears precision forging were evaluated by this method. The results show that the best forming quality can be achieved when the punches were added with bosses, the web located at the middle plant of the gear, and the web thickness was 30 percent of the inner hole diameter. Verification experiments taking the above optimized parameters were performed on a 7.8 MN double action hydraulic press. The trial products were formed well. And their geometric precision meets the demand. The verification result shows that the optimization of the influential factors, according to the simulations and the evaluation method, can improve the forming quality. The new structure of precision forging die-set and the new evaluation method guarantee a high forming quality ofhalfaxel gears.

关键词： warm precision forging half axle gears forming quality die structure web

Combined effects of temperature and humidity on the interaction between tomato and Botrytis cinerea revealed by integration of histological characteristics and transcriptome sequencing

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Horticulture Research 2023年第2期10卷 53-64页

作者： Tianzhu Li jie zhou Jianming Li College of Horticulture Northwest Agricultural and Forestry UniversityYangling 712100China

The environment significantly impacts the interaction between plants and pathogens,thus remarkably affecting crop disease ***,the detailed combined mechanisms of temperature and humidity influencing this interaction remain *** this study,the interaction between tomato and Botrytis cinerea in various temperature and humidity conditions was analyzed by histological observation and a dual RNA-seq *** showed that low humidity was not favorable for mycelial growth,resulting in infection *** high and low temperatures at high humidity successfully inhibited pathogenic infection and disease incidence in the tomato plants,thus enhancing their resistance to *** high temperature and high humidity(HH)treatment induced the upregulation of light reaction genes,increased the net photosynthetic rate,and expanded the chloroplast morphology of infected *** HH treatment also inhibited the expression of cell cycle-related genes of ***,interfered with conidial germination andmycelial growth,and damagedmycelial cell *** and high humidity(LH)treatment induced the expression of cell wall modification genes and remodeled the cell wall morphology of tomatoes in response to *** addition,the downregulated fungal catabolic genes and the abnormal increase in electron density ofmycelial cells under LH treatment subsequently reduced the infection ability of *** results further explain the coupled effects of temperature and humidity on plant defenses and pathogen virulence,and provide a potential means to control gray mold.

关键词： inhibited histological humidity

Global Existence of Strong Solutions for the Generalized Navier-Stokes Equations with Damping

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 627-634页

作者： Xiao-jing CAI Yan-jie zhou School of mathematics and statistics Beijing Technology and Business UniversityBeijing 100048China

This paper mainly focus on the global existence of the strong solutions for the generalized NavierStokes equations with damping. We obtain the global existence and uniqueness when α ≥5/4 for β ≥ 1 and when 1/2+β/... 详细信息

关键词： generalized Navier-Stokes equations damping global existence

OPTIMAL TRACK SEEKING CONTROL OF DUAL-STAGE ACTUATOR FOR HIGH DENSITY HARD DISK DRIVES

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Acta Mechanica Solida Sinica 2006年第4期19卷 297-306页

作者： zhou Haomiao Wang jie zhou Youhe Zheng Xiaojing Department of Mechanics and Engineering Science College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China

Based on generalized the variation method, by introducing Hamilton function and Lagrange multiplier, this paper proposed a linear quadratic optimal control strategy for an incomplete controllable system with fixed terminal state and time. Applying the proposed optimal control to the simple two-input dual-stage actuator magnetic head positioning system with three degrees-of-freedom, the simulation results show that the system has no residual vibration at the terminal position and time, which can reduce the total access time during head positioning process. To verify the validation of the optimal control strategy of three degrees-of-freedom spring-mass models in actual magnetic head positioning of hard disk drives, a finite element model of an actual magnetic head positioning system is presented. Substituting the optimal control force from simple three degrees-of-freedom spring-mass models into the finite element model, the simulation results show that the magnetic head also has no residual vibration at the end of track-to-track travel. That is to say, the linear quadratic optimal control technique based on simple two-input dual- stage actuator system with three degrees-of-freedom proposed in this paper is of high reliability for the industrial application of an actual magnetic head positioning system.

关键词： hard disk drives optimal track seeking control generalized variation method residual vibrationless

Effects of ECAE processing temperature on the microstructure, mechanical properties, and corrosion behavior of pure Mg

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International Journal of Minerals,Metallurgy and Materials 2015年第6期22卷 639-647页

作者： Zhi Li Shi-jie zhou Nan Huang School of Materials Science and Engineering Southwest Jiaotong University School of Pharmacology Chengdu Medical College College of Materials and Chemistry & Chemical Engineering Chengdu University of Technology

A two-step equal channel angular extrusion（ECAE） procedure was used to process pure Mg. The effects of ECAE processing temperature on the microstructure, mechanical properties, and corrosion behavior of pure Mg were studied. The results show that the average grain size of pure Mg decreases with decreasing extrusion temperature. After ECAE processing at 473 K, fine and equiaxed grains（~9 μm） are obtained. The sample processed at 473 K exhibits the excellent mechanical properties, whereas the sample processed at 633 K has the lowest corrosion rate. The improved corrosion resistance and mechanical properties of pure Mg by ECAE are ascribed to grain refinement and microstructural modification.

关键词： magnesium equal channel angular pressing microstructure corrosion resistance mechanical properties

Rational Design of Biomolecules/Polymer Hybrids by Reversible Deactivation Radical Polymerization (RDRP) for Biomedical Applications

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Chinese Journal of Polymer Science 2021年第9期39卷 1093-1109页

作者： jie zhou Xiao-Yuan Zhang Zhi-Qiang Su State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Advanced Functional Polymer CompositesBeijing University of Chemical TechnologyBeijing 100029China

Hybrids,produced by hybridization of proteins,peptides,DNA,and other new biomolecules with polymers,often have unique functional *** properties,such as biocompatibility,stability and specificity,lead to various smart *** review mainly introduces biomolecule polymer hybrid materials by reversible deactivation radical polymerization(RDRP),emphasizing reverse addition-fragmentation chain transfer(RAFT)polymerization,and nitroxide mediated polymerization(NMP).It includes the methods of RDRP to improve the biocompatibility of biomedical materials and organisms by surface *** key to the current synthesis of biomolecule polymer hybrids is to control ***,this review describes several different kinds of biomolecule polymer hybrid materials and their applications in the biomedical *** progresses provide ideas for the investigation of biodegradable and highly bioactive biomedical soft tissue *** research hotspots of nanotechnology in biomedical fields are controlled drug release materials and gene therapy carrier *** showed that RDRP method could improve the therapeutic effect and reduce the dosage and side effects of the ***,by means of RDRP,the original materials can be modified to develop intelligent polymer materials as membrane materials with selective permeability and surface modification.

关键词： Biomolecule-polymer hybrids RDRP Biomedical applications Drug release Nanotechnology