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Wavefronts of a Nonlocal State-dependent Time Delay Model

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Acta Mathematica Sinica,English Series 2020年第1期36卷 77-92页

作者： rui jun XIE Rong yuan Zhi Hui YANG School of Statistics and Applied Mathematics Anhui University of Finance and EconomicsBengbu 233030P.R.China School of Mathematical sciences Beijing Normal UniversityBeijing 100875P.R.China

This paper is concerned with the travelling wavefronts of a nonlocal dispersal cooperation model with harvesting and state-dependent delay,which is assumed to be an increasing function of the population density with lower and upper ***,state-dependent delay is introduced into a nonlocal reaction-diffusion *** conditions of Schauder's fixed point theorem are proved by constructing a reasonable set of functionsΓ(see Section 2)and a pair of upper-lower solutions,so the existence of traveling wavefronts is *** present study is continuation of a previous work that highlights the Laplacian diffusion.

关键词： Nonlocality state-dependent delay cooperation traveling wavefronts

Max-utility subcarrier allocation for heterogeneous services in wireless OFDM system

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The Journal of china Universities of Posts and Telecommunications 2009年第1期16卷 51-57页

作者： CHEN Zi-xiong SUN Kai yuan jun wang Ying Key Laboratory of Universal Wireless Communication Beijing University of Posts and Telecommunications Beijing 100876 China college of Eleclxonic Information Engineering Inner Mongolia University Hohhot 010021 China

In future wireless network, one user will require multiple homogeneous or heterogeneous services simultaneously. Then, the scheduling algorithm is not only responsible for assigning a resource block to different users but also sharing the assigned resource block among multiple services for one user. Most of the traditional scheduling algorithms are designed to serve one service per user, and cannot be applied directly to this scenario because of the fairness criterion. This article focuses on adaptive resource allocation for multiple services per user at the downlink of orthogonal frequency division multiplexing （OFDM） based system. This article addresses this integrative resource scheduling problem based on utility function. First, the optimal algorithm for dynamic subcarrier allocation and share is deduced for homogeneous best-effort service system. Then the algorithm is extended to heterogeneous services system by classifying the delay sensitive service according to the head-of-line packet delay. The design goal is to maximize aggregate utility function to exploit multiuser diversity gain to the greatest extent even as guaranteeing quality of service （QoS） for delay sensitive service.

关键词： heterogeneous service multiuser diversity radio resource scheduling utility function

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跳水训练数据管理与分析系统设计与应用

体育科学 2004年第10期24卷 41-45页

作者：熊媛张毅陈小平姜侃清华大学自动化系北京100084 清华大学体育教研部北京100084 清华大学电子工程系北京100084

根据跳水队训练和比赛的实际需要 ,将计算机辅助训练系统应用于跳水训练 ,建立了一套跳水训练数据管理与分析系统。该系统基于 Visual Basic6 .0编程平台进行开发 ,连接 Access数据库 ,并留有视频处理功能接口。结合实际需求给出了系统... 详细信息

根据跳水队训练和比赛的实际需要 ,将计算机辅助训练系统应用于跳水训练 ,建立了一套跳水训练数据管理与分析系统。该系统基于 Visual Basic6 .0编程平台进行开发 ,连接 Access数据库 ,并留有视频处理功能接口。结合实际需求给出了系统的设计思想和总体框架 ,分析了系统功能结构以及信息处理结构。

关键词：跳水数据管理分析系统设计应用

An improved cross-domain role mapping mechanism

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An improved cross-domain role mapping mechanism

Selective targeted adsorption and inactivation of antibiotic-resistant bacteria by Cr-loaded mixed metal oxides

2010 International Conference on Circuit and Signal Processing (ICCSP 2010) & 2010 Second IITA International Joint Conference on Artificial Intelligence (IITA-JCAI 2010)

作者： jun Zheng,Yichun Chen School of Computer science and Technology beijing Institute of Technology beijing 100081,china Qikun Zhang,yuan TAN and Qiongxin Liu School of Computer science and Technology beijing Institute of Technology beijing 100081,china

Aimed at the aberrations of inter-domain role mapping issues including privilege-aberration and role aberration,an improved inter-domain role mapping mechanism was purposed in this article,and it can guarantee the consistency of the user privilege and the relationships among *** makes utility of the role-privilege relation,and maintains a "permitted privilege list" and a "forbidden privilege list" for each role,and thus provides more flexibility for role mapping,and it can determine whether a certain role-mapping is legal within constant time using closure algorithm,and to make that algorithm more efficiency,a pre-calculation method is purposed.

关键词： role mapping inter-domain role-privilege utility

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Frontiers of Environmental science & Engineering 2022年第6期16卷 1-12页

作者： Yanlin Li Bo wang Lei Zhu Yixing yuan Lujun Chen jun Ma State Key Laboratory of Urban Water Resources and Environment(SKLUWRE) Harbin Institute of TechnologyHarbin 150090China Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology School of Environmental Science and Safety EngineeringTianjin University of TechnologyTianjin 300384China Jiangsu Yihuan Group Co. Ltd.Yixing 214206China School of Environment Tsinghua UniversityBeijing 100084China

Herein we provide a novel high-efficiency nanocomposite for bacterial capture based on mixed metal oxides(MMOs)with deleterious chromium *** both the layer structure of layered double hydroxides(LDHs)and the magnetic properties of Fe,MMOs enrich the location of ionic forms on the surface,providing a good carrier for adsorption of the heavy metal Cr(VI).The capacity for adsorption of Cr(VI)by MMOs can be as high as 98.80 mg/*** prepared Cr(VI)-MMOs achieved extremely expeditious location of gram-negative antibiotic-resistant ***-1 by identifying lipid ***-MMOs with a Cr loading of 19.70 mg/g had the best bactericidal effect,and the concentration of ***-1 was decreased from~10^(8) to~10^(3) CFU/mL after 30 min of *** binding of nitrogen and phosphorus hydrophilic groups to chromate generated realistic models for density functional theory(DFT)*** specific selectivity of MMOs toward bacterial cells was improved by taking Cr(VI)as a transferable medium,thereby enhancing the antibacterial activity of *** the combined action of chemical and physical reactions,Cr(VI)-MMOs achieved high capacity for inactivation of ***,the metallic elements ratio in Cr-MMOs remained stable in their initial valence states after *** guaranteed high removal efficiency for both heavy metals and bacteria,allowing recycling of the adsorbent in practical applications.

关键词： Heavy metal adsorption Magnetic hydrotalcite ARBs removal Cr(VI)-MMOs combined antibacterial activity

Facile and Cost-Efficient Synthesis of Photovoltaic Polymers via Direct Arylation Coupling

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Chinese Journal of Polymer science 2023年第11期41卷 1663-1685,I0004页

作者： Xiao-Chen wang yuan Zhang Jia-Xin Yang Jin-jun Shao Ming-Feng wang Yong-Fang Li School of Materials science and Engineering Shaanxi Normal UniversityXi'an 710119China Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) School of Flexible Electronics(Future Technologies)Nanjing Tech UniversityNanjing 211816China School of science and Engineering The Chinese University of Hong KongShenzhen 518172China beijing National Laboratory for Molecular sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

As the high calibre candidate of lightweight and flexible solar cells,polymer solar cells(PSCs)have made tremendous progress in recent ***,the active photovoltaic materials in PSCs are mainly synthesized by metal-mediated coupling reaction requiring harsh reaction conditions,multiple-step synthesis,and cumbersome purification,which is not cost-efficient and may bring toxicity *** is not favorable to the production of photovoltaic polymers and PSC devices on a large scale,and therefore unsuitable for the PSCs *** arylation coupling reaction via aromatic C―H bonds activation enables the synthesis of conjugated polymers under mild conditions and simultaneously reduces synthetic steps,difficulty,and toxic reaction *** review provides an overview of the history of preparing representative photovoltaic polymers utilized in PSCs through direct arylation reactions and discusses the activity and selectivity of C―H bonds in typical building blocks under different reaction ***,the impact of direct arylation condition on defect formation and photovoltaic performance of the photovoltaic polymers is addressed and compared with conventional Stille coupling methods.

关键词： Photovoltaic polymers Direct arylation coupling C―H bonds activation Polymer solar cells(PSCs) Organic solar cells(OSCs) Low-cost

Discovering the ultralow thermal conductive A_(2)B_(2)O_(7)-type high-entropy oxides through the hybrid knowle dge-assiste d data-driven machine learning

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Journal of Materials science & Technology 2024年第1期168卷 131-142页

作者： Ying Zhang Ke Ren William Yi wang Xingyu Gao ruihao yuan jun wang Yiguang wang Haifeng Song Xiubing Liang Jinshan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Innovation Center NPU ChongqingChongqing 401135China Institute of Advanced Structure Technology Beijing Institute of TechnologyHaidian DistrictBeijing 100081China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Defense Innovation Institute Academy of Military Sciences of the PLA of ChinaBeijing 100071China

Lattice engineering and distortion have been considered one kind of effective strategies for discovering advanced *** instinct chemical flexibility of high-entropy oxides(HEOs)motivates/accelerates to tailor the target properties through phase transformations and lattice ***,a hybrid knowledge-assisted data-driven machine learning(ML)strategy is utilized to discover the A_(2)B_(2)O_(7)-type HEOs with low thermal conductivity(κ)through 17 rare-earth(RE=Sc,Y,La-Lu)solutes optimized A-site.A designing routine integrating the ML and high throughput first principles has been proposed to predict the key physical parameter(KPPs)correlated to the targetedκof advanced *** the smart-designed 6188(5RE_(0.2))_(2)Zr_(2)O_(7)HEOs,the best candidates are addressed and validated by the princi-ples of severe lattice distortion and local phase transformation,which effectively reduceκby the strong multi-phonon scattering and weak interatomic ***,(Sc_(0.2)Y_(0.2)La_(0.2)Ce_(0.2)Pr_(0.2))_(2)Zr_(2)O_(7)with predictedκbelow 1.59 Wm^(−1)K^(−1)is selected to be verified,which matches well with the ex-perimentalκ=1.69 Wm^(−1)K^(−1)at 300 K and could be further decreased to 0.14 Wm^(−1)K^(−1)at 1473 ***,the coupling effects of lattice vibrations and charges on heat transfer are revealed by the cross-validations of various models,indicating that the weak bonds with low electronegativity and few bond-ing charge density and the lattice distortion(r∗)identified by cation radius ratio(r A/r B)should be the KPPs to decreaseκ*** work supports an intelligent designing strategy with limited atomic and electronic KPPs to accelerate the development of advanced multi-component HEOs with proper-ties/performance at multi-scales.

关键词： High-entropy oxides Thermal conductivity Pyrochlore Key physical parameter First-Principles

Picosecond time-resolved X-ray ferromagnetic resonance measurements at Shanghai synchrotron radiation facility

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Nuclear science and Techniques 2022年第5期33卷 126-134页

作者： Xia Yang Jie-Feng Cao jun-Qin Li Fang-yuan Zhu rui Yu Jian He Zi-Long Zhao Yong wang Ren-Zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China university of Chinese Academy of sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

An experimental picosecond time-resolved X-ray ferromagnetic resonance(TR-XFMR)apparatus with a time resolution of 13 ps(RMS)or 31 ps(FWHM)was constructed and demonstrated in the 07U and 08U1A soft X-ray beamlines at the Shanghai Synchrotron Radiation Facility(SSRF)using pump-probe detection and X-ray magnetic circular dichroism(XMCD)*** and time-resolved ferromagnetic resonance was excited by continuous microwave phase-locking of the bunch clock within the photon beam during synchrotron radiation and was characterized by detecting the magnetic circular dichroism signals of the elements of interest in the magnetic *** this equipment,we measured the amplitude of the element-specific moment precession during ferromagnetic resonance(FMR)at 2 GHz in a single Ni81Fe19layer.

关键词： Ferromagnetic resonance Time resolution Pump-probe Synchrotron radiation

Influence of hot rolling on the microstructure of lean duplex stainless steel 2101

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International Journal of Minerals,Metallurgy and Materials 2019年第10期26卷 1266-1273页

作者： Zhi-jun Gao Jing-yuan Li Zhi-hui Feng Yi-de wang School of material science and engineering University of Science and Technology BeijingBeijing100083China Institute of Engineering Technology University of Science and Technology BeijingBeijing100083China

In this work, the microstructure and the strain partitioning of lean duplex stainless steel 2101 (LDX 2101) during different hot-rolling processes are investigated by optical microscopy and electron-backscattered diffraction (EBSD). The results show that the LDX 2101 exhibits poor thermoplasticity at high temperature. The four-pass hot-rolled plates show fewer edge-cracking defects and superior thermoplasticity compared with the two-pass hot-rolled plates prepared at different temperature. The phase boundary is the weakest site in the LDX 2101. The cracks are initiated and propagated along the phase boundaries during the hot-rolling process. According to the EBSD analysis, the increase of the hot-rolling pass can dramatically improve the strain distribution in ferrite and austenite phases and promote the strain transmission in the constituent phases, thereby improving the coordinated deformation ability of the two phases. This effect further in- creases the thermoplasticity and reduces the formation of edge cracks in LDX 2101.

关键词： lean duplex stainless steel hot-rolling process thermoplasticity strain distribution