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Composition-integral Type Operators from F（p, q, s） Spaces to Bloch-type Spaces

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Chinese Quarterly Journal of Mathematics 2012年第3期27卷 352-356页

作者： lv xiao-fen YING Shao-hong College of Mathematics and Science Xiamen University Xiamen 361005 China

This paper deals with the boundedness and compactness of the compositionintegral type operators T g, from F (p, q, s) spaces to(little) Bloch-type spaces in the unit ball of C n , where Tg,φf(z) =∫01fφ(tz)Rg(tz)(dt... 详细信息

关键词： F (p, q, s) space Bloch-type space boundedness compactness

Proton Spin from General Colour Symmetry Model

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Chinese Physics Letters 2001年第4期18卷 508-510页

作者： lv xiao-Fu LI Ying-Chuan SUN Ming-Shan WEN Xin-Min Department of Physics Sichuan UniversityChengdu 610064 Institute of Nuclear Science and Technology Sichuan UniversityChengdu 610064 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

The quark wave function in a proton has been calculated by using the global colour symmetry model. We find that the property of this wave function is closely related to the nonperturbative vacuum configuration. Using the wave function we make the calculation of the matrix element of the axial vector current of the quarks in the proton ground state. Its value is found to be 0.17, which is perfectly consistent with 0.23(+6).

关键词： configuration. state. quark

Effects of Ce-rich RE on microstructure and mechanical properties of as-cast Mg-8Li-3Al-2Zn-0.5Nd alloy with duplex structure

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Progress in Natural Science:Materials International 2019年第1期29卷 103-109页

作者： Xiang Peng Guohua Wu lv xiao Hao Ji Jie Zhang Wenbing Zou Zhongquan Li Wencai Liu National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong University Shanghai Spaceflight Precision Machinery Institute

The effects of Ce-rich RE on the microstructure and mechanical properties of as-cast Mg-8Li-3Al-2Zn-0.5Nd-x RE(x = 0, 1, 2, 3 wt%) alloys were investigated. The results indicated that the as-cast Mg-8Li-3Al-2Zn-0.5Nd alloy mainly consisted of α-Mg, β-Li, AlLi, MgLi2 Al and Al2 Nd phases. With the addition of Ce-rich RE in the alloy,Al3 RE and Al2 RE phases generated and gradually grew into net-like or block-like structure. With the addition of RE, Al-RE phases generated by consuming Al element and, thus, less Al element was dissolved in the matrix and less AlLi phase formed. Furthermore, less AlLi phase means that more Li element released to cause the increase ofβ-Li phase and refine the α-Mg phase. Under the influence of these factors, adding more RE led to higher elongation and lower tensile strength and hardness. With the addition of Ce-rich RE, the yield strength and ultimate tensile strength of the as-cast Mg-8Li-3Al-2Zn-0.5Nd alloy gradually decreased from 180 to 152 MPa and from 215 to 193 MPa, respectively, while the elongation was remarkably improved from 21.1% to 40.2%.

关键词： Mg-Li alloy Rare earth Ce Microstructure Mechanical property

Energy consumption optimization for edge computing-supported cellular networks based on optimal transport theory

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Science China(Information Sciences) 2024年第2期67卷 201-218页

作者： Xiangyu lv xiaohu GE Yi ZHONG Qiang LI Yong xiao School of Electronic Information and Communications Huazhong University of Science and Technology

With advancements in mobile communication technologies, there have been multiple user device(UD) connections to cellular networks. Because of changes in the spatial distribution of UDs and application requirements, the traditional offloading mechanism based on the nearest distance will result in heavy loads for some base stations(BSs). Because there is a high-order relationship between the energy consumption of the BS processing tasks and the number of computing tasks, the traditional offloading mechanism will result in high energy consumption, and UD’s offloading decision must be dynamically adjusted. The offloading decision of UDs is optimized based on detailed information about various parameters associated with a network from the standpoint of distribution. This information includes details regarding the spatial distribution of UDs,application requirements, and the offloading period of computing tasks. Based on optimal transport theory,an energy consumption optimization algorithm is suggested to lower the total amount of energy consumed by the offloading process of UDs’ computing tasks by reasonably planning the offloading BSs of the UDs in the networks. The simulation results show that the proposed offloading mechanism based on energy consumption optimization reduces the total energy consumption of the offloading process by 28.09% when compared to the traditional offloading mechanism, and the traffic managed by each BS is balanced.

关键词： optimal transport theory edge computing energy consumption reduction dynamic voltage frequency scaling

Growth of Self-Catalyzed InP Nanowires by Metalorganic Chemical Vapour Deposition

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Chinese Physics Letters 2012年第12期29卷 145-147页

作者： lv xiao-Long ZHANG Xia YAN Xin LIU xiao-Long CUI Jian-Gong LI Jun-Shuai HUANG Yong-Qing REN xiao-Min State Key Laboratory of Information Photonics&Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876

The fabrication of self-catalyzed InP nanowires(NWs)is investigated under different growth *** droplets induced by surface reconstruction act as nucleation sites for NW *** standing NWs with uniform cross sections are obtained under optimized *** is confirmed that the growth rate of NWs is strongly affected by the surface diffusion adatoms while contributions from the direct impingement of vapor species onto the In droplets can be *** results indicate that the droplet acts as an adatom collector rather than a ***,the diffusion flow rate of adatoms increases with time at the beginning of growth and stabilizes as the growth proceeds.

关键词： nanowires diffusion negligible

Formation and control of disinfection byproducts and toxicity during reclaimed water chlorination： A review

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Journal of Environmental Sciences 2017年第8期29卷 51-63页

作者： Ye Du xiao-Tong lv Qian-Yuan Wu Da-Yin Zhang Yu-Ting Zhou Lu Peng Hong-Ying Hu Environmental Simulation and Pollution Control State Key Joint Laboratory State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC) School of Environment Tsinghua University Beijing 100084 China Key Laboratory of Microorganism Application and Risk Control of Shenzhen Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China Shenzhen Environmental Science and New Energy Technology Engineering Laboratory Tsinghua-Berkeley Shenzhen Institute Shenzhen518055 China

Chlorination is essential to the safety of reclaimed water; however, this process leads to concern regarding the formation of disinfection byproducts（DBPs） and toxicity. This study reviewed the formation and control strategies for DBPs and toxicity in reclaimed water during *** regulated and emerging DBPs have been frequently detected in reclaimed water during chlorination at a higher level than those in drinking water, indicating they pose a greater risk to humans. Luminescent bacteria and Daphnia magna acute toxicity, anti-estrogenic activity and cytotoxicity generally increased after chlorination because of the formation of DBPs. Genotoxicity by umu-test and estrogenic activity were decreased after chlorination because of destruction of toxic chemicals. During chlorination, water quality significantly impacted changes in *** tended to attenuate toxicity changes by reacting with chlorine to form chloramine,while bromide tended to aggravate toxicity changes by forming hypobromous acid. During pretreatment by ozonation and coagulation, disinfection byproduct formation potential（DBPFP）and toxicity formation potential（TFP） occasionally increase, which is accompanied by DOC removal; thus, the decrease of DOC was limited to indicate the decrease of DBPFP and TFP. It is more important to eliminate the key fraction of precursors such as hydrophobic acid and hydrophilic neutrals. During chlorination, toxicities can increase with the increasing chlorine dose and contact time. To control the excessive toxicity formation, a relatively low chlorine dose and short contact time were required. Quenching chlorine residual with reductive reagents also effectively abated the formation of toxic compounds.

关键词： Reclaimed water Chlorination Disinfection byproducts Toxicity Precursor

Hybrid gradient vector fields for path-following guidance

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Defence Technology（防务技术） 2023年第10期28卷 165-182页

作者： Yi-yang Zhao Zhen Yang Wei-ren Kong Hai-yin Piao Ji-chuan Huang xiao-feng lv De-yun Zhou School of Electronics and Information Northwestern Polytechnical UniversityXi’An710072China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China The 93147th Unit of Chinese PLA Air Force Chengdu610091China

Guidance path-planning and following are two core technologies used for controlling un-manned aerial vehicles(UAVs)in both military and civilian ***,only a few approaches treat both the technologies *** this study,an innovative hybrid gradient vector fields for path-following guidance(HGVFs-PFG)algorithm is proposed to control fixed-wing UAVs to follow a generated guidance path and oriented target curves in three-dimensional space,which can be any combination of straight lines,arcs,and helixes as motion *** algorithm aids the creation of vector fields(VFs)for these motion primitives as well as the design of an effective switching strategy to ensure that only one VF is activated at any time to ensure that the complex paths are followed *** strategies designed in earlier studies have flaws that prevent the UAV from following arcs that make its turning angle too *** proposed switching strategy solves this problem by introducing the concept of the virtual ***,the performance of the HGVFs-PFG algorithm is verified using a reducedorder autopilot and four representative simulation *** simulation considers the constraints of the aircraft,and its results indicate that the algorithm performs well in following both lateral and longitudinal control,particularly for curved *** general,the proposed technical method is practical and competitive.

关键词： Unmanned aerial vehicle(UAV) Path-following guidance(PFG) Hybrid gradient vector field(HGVF) Switching strategy

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高速铁路接触网吊弦拉扭多工况耦合力学性能

计算机仿真 2024年第8期41卷 155-160页

作者：吕笑文刘叶诚谭海恒徐志彪五邑大学轨道交通学院广东江门529000

吊弦是电气化铁路接触网的重要组成部件,随着列车的不断提速,对高速铁路接触网吊弦提出了更高的要求。针对吊弦在拉-扭耦合应力下的服役工况,采用有限元仿真软件对其进行拉-扭多工况耦合模拟。仿真结果表明:纯扭转载荷作用下吊弦的轴向... 详细信息

吊弦是电气化铁路接触网的重要组成部件,随着列车的不断提速,对高速铁路接触网吊弦提出了更高的要求。针对吊弦在拉-扭耦合应力下的服役工况,采用有限元仿真软件对其进行拉-扭多工况耦合模拟。仿真结果表明:纯扭转载荷作用下吊弦的轴向位移及扭转角度与扭转载荷近似呈线性正相关,沿吊弦丝线截面圆周方向,等效应力呈层状分布;拉-扭耦合应力下,其扭转角随载荷的增大而增大,但应力分布无明显规律。特别地,当耦合电流作用时,拉-扭载荷作用下,吊弦丝线的局部应力显著增大,抗变形能力降低。

关键词：吊弦数值模拟力学性能拉扭耦合载流

微波消解-电感耦合等离子体发射光谱法测定锡矿中7种元素的研究

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广州化工 2024年第2期52卷 179-180,183页

作者：秦婷吕晓华张金龙王婷马玲乌鲁木齐海关技术中心新疆乌鲁木齐830063

采用微波消解-电感耦合等离子体发射光谱检测方法对锡矿中锌、铜、铁、铅、砷、锑、铋元素进行分析。锡矿样品以盐酸、硝酸、氢氟酸为消解液,经微波消解后,用电感耦合等离子体发射光谱仪测定消解液中锌、铜、铁、铅、砷、锑、铋元素含... 详细信息

采用微波消解-电感耦合等离子体发射光谱检测方法对锡矿中锌、铜、铁、铅、砷、锑、铋元素进行分析。锡矿样品以盐酸、硝酸、氢氟酸为消解液,经微波消解后,用电感耦合等离子体发射光谱仪测定消解液中锌、铜、铁、铅、砷、锑、铋元素含量。在选定的测定条件下,锌、铜、砷、锑、铋元素在浓度0~5 mg/L范围内,铁、铅元素在浓度0~20 mg/L范围内,线性关系良好,方法的检出限在0.0008%~0.0016%。该方法简便快速,稳定性好,结果准确可靠,适用于锡矿中常规元素含量的分析。

关键词：锡矿锌、铜、铁、铅、砷、锑、铋微波消解电感耦合等离子体发射光谱