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Multi-Resources Management in 6G-Oriented Terrestrial-Satellite Network

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China Communications 2021年第9期18卷 24-36页

作者： shu fu Bibo Wu Shaohua Wu Fang Fang College of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Space Information Network and Intelligent Information fusion Chongqing UniversityChongqing 400044China Communication Engineering Research Centre Harbin Institute of Technology(Shenzhen)Guangdong 518055China Peng Cheng Laboratory Shenzhen 518055China Department of Engineering Durham UniversityDurham DH13LEU.K

The six-generation(6G)wireless network is expected to satisfy the requirements of ubiquitous connectivity and intelligent *** networks(TSN)enable seamless coverage for terrestrial users in a wide area,making it very promising in *** data traffic in TSNs surges,the integrated management for caching,computing,and communication(3C)has attracted much research *** this paper,we investigate the multi-resource management in the uplink and downlink transmission of TSN,*** particularly,we aim to guarantee both throughput fairness and data security in the uplink transmission of *** the intermittent communication of the satellite,we introduce two kinds of relays,i.e.,terrestrial relays(TRs)and aerial relays(ARs)to improve the system throughput performance in the downlink transmission of ***,we study a specific case of TSN with the uplink and downlink transmission,and the corresponding simulation results validate the effectiveness of our proposed schemes.

关键词： downlink transmission multi-resource management relay terrestrial-satellite networks up-link transmission

Spectral Parameters of Nd^(3+) in the Nd^(3+):GdMgB_5O_(10) Crystal

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Chinese Journal of Structural Chemistry 2005年第4期24卷 419-423页

作者： FANJun-Mei LINZhou-Bin ZHANGLi-Zhen HUZu-shu WANGGuo-fu StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatterTheChineseAcademyofSciencesFuzhouFujian350002China

The absorption and emission spectra of Nd3+:GdMgB5O10 crystal were inves- tigated. Based on Judd-Ofelt theory the three parameters of oscillator strength were obtained as follows: ?2 = 2.099×10-20 cm2, ?4 = 4.599×10-20 cm2 and ?6 = 5.139×10-20 cm2. The fluorescence branch rations were also obtained: β1 = 0.424, β2 = 0.474, β3 = 0.094 and β4 = 0.005. The radiative lifetime is 416 μs and quantum efficiency ηc 9.13%. The emission cross section σp (1.06 μm) is 4.38×10-19 cm2.

关键词： spectral parameters Nd3+:GdMgB5O10 crystal Judd-Ofelt theory

Accelerating Effect of Wetting-Drying Cycles on Steel Bar Corrosion in Concrete

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Journal of China University of Mining and Technology 2005年第3期15卷 197-202页

作者： LI Guo YUAN Ying-shu LI fu-min School of Architecture and Civil Engineering China University of Mining and Technology Xuzhou Jiangsu 221008 China

Raining and sun-shining processes in natural climate were simulated by water spraying and infrared lightshining alternately as wetting-drying cycles in accelerated durability test. The accelerating effects of the wet-ting-drying cycles and the variation of corrosion current density and corrosion potential of steel bar in concrete undersuch conditions were studied. The result shows that the main reason leading to accelerating corrosion of steel bar inconcrete is the wetting-drying cycles, which can cause the increase of corrosion potential difference between the an-ode and cathode of steel bar corrosion cell and the decrease of concrete resistance. Corrosion rate of the steel bar inconcrete under four typical conditions, including wetting-drying cycle, long time submerging in water, long time ex-posure to indoor and outdoor environment were measured and compared. The test results indicate that the corrosionrates under the four typical conditions are in the order of spraying and infrared light shining cycles, outdoor environ-ment, indoor environment, and submerging in water, respectively.

关键词： wetting-drying cycle concrete steel bar corrosion rate

The distribution characteristics of heavy metals in Guiyang urban soils

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Chinese Journal Of Geochemistry 2012年第2期31卷 174-180页

作者： LI Xiaoyan CAO Yijin QI Le shu fu School of Geographic and Environmental Sciences Guizhou Normal University Guiyang 550001 China

Guiyang is located in southwestern China,which is a famous tourism city,and is awarded the title of"the Summer Capital of China".A study on heavy metals in Guiyang urban soils was *** results showed that the concentrations of Cd,Cu,Ni,Pb and Zn in Guiyang urban soils are significantly higher than their background values and Cu,Zn and Pb in Guiyang soils are accumulated *** distribution characteristics of heavy metals in 3 districts are described as follows:the level of heavy metals in soils follows the order of Nanming District> Yunyan District>Xiaohe *** spatial distribution of metals in urban soils of Guiyang shows that the level of metals in the central and eastern parts of Guiyang is relatively high,and its characteristics are attributed to the influence of commercial activities,heavy traffic and industrial *** with some other cities in China,Guiyang is characterized by relatively high accumulation level of Cd,Cu,and Zn in its soils.

关键词：土壤重金属旅游城市贵阳市特征描述中国西南部重金属分布城市土壤土壤铜

NEW METHOD FOR PAPR REDUCTION BASED ON UNION STRATEGY IN OFDM SYSTEM

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Journal of Electronics(China) 2014年第5期31卷 427-432页

作者： Ji Ce fu shu Zhao Yue Institute of Information Science and Engineering Northeastern University

Because of the high Peak to Average Power Ratio(PAPR) in Orthogonal Frequency Division Multiplexing(OFDM) system, a union algorithm for PAPR reduction, combined with modified Active Constellation Extension Smart Gradient-Project(ACE-SGP) algorithm and adaptive clipping algorithm, is proposed in this paper. First of all, an adaptive strategy is used to control the size of clipping level A. Secondly, a novel step factor m is adopted to complete iterative computations in order to increase the convergence speed greatly. Simulation results show that the modified algorithm has reduced the PAPR and improved the convergence speed significantly without side information and any processing at the receiver end.

关键词： Orthogonal Frequency Division Multiplexing(OFDM) Peak to Average Power Ratio(PAPR) Active Constellation Extension(ACE) Smart Gradient-Project(SGP) Adaptive

Synthesis of Highly Branched Poly(ε-caprolactone) by Self-condensing Atom Transfer Radical Polymerization of Macroinimers

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Chinese Chemical Letters 2006年第3期17卷 373-376页

作者： Rui Xue LIU Yan SHI Zhi Feng fu shu Ke JIAO Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing University of Chemical Technology Beijing 100029

Branched poly（ε-capmlactone） was synthesized by self-condensing atom transfer radical polymerization of macroinimer, α-acryloyoxy-ω-2-bromopropionyloxy poly（ε-caprolactone）, which was prepared by enzyme-catalyzed ring-opening polymerization of ε-caprolactone with 2-hydroxylethyl acrylate as initiator and esterification of the ω-hydroxyl group of the obtained poly（ε-caprolactone） by 2-bromopropionyl bromide.

关键词： Self-condensing vinyl polymerization atom transfer radical polymerization branched polymers poly(ε-caprolactone).

Seepage safety monitoring model for an earth rock dam under influence of high-impact typhoons based on particle swarm optimization algorithm

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Water Science and Engineering 2017年第1期10卷 70-77页

作者： Yan Xiang shu-yan fu Kai Zhu Hui Yuan Zhi-yuan Fang Dam Safety Management Center of the Ministry of Water Resources Nanjing Hydraulic Research InstituteNanjing 210029China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China College of Mechanics and Materials Hohai UniversityNanjing 210098China School of Water Resources and Hydraulic Engineering Yunnan Agricultural UniversityKunming 650000China

Extreme hydrological events induced by typhoons in reservoir areas have presented severe challenges to the safe operation of hydraulic structures. Based on analysis of the seepage characteristics of an earth rock dam, a novel seepage safety monitoring model was constructed in this study. The nonlinear influence processes of the antecedent reservoir water level and rainfall were assumed to follow normal distributions. The particle swarm optimization （PSO） algorithm was used to optimize the model parameters so as to raise the fitting accuracy. In addition, a mutation factor was introduced to simulate the sudden increase in the piezometric level induced by short-duration heavy rainfall and the possible historical extreme reservoir water level during a typhoon. In order to verify the efficacy of this model, the earth rock dam of the Siminghu Reservoir was used as an example. The piezometric level at the SW1-2 measuring point during Typhoon Fitow in 2013 was fitted with the present model, and a corresponding theoretical expression was established. Comparison of fitting results of the piezometric level obtained from the present statistical model and traditional statistical model with monitored values during the typhoon shows that the present model has a higher fitting accuracy and can simulate the uprush feature of the seepage pressure during the typhoon perfectly.

关键词： Monitoring model Particle swarm optimization algorithm Earth rock dam Lagging effect Typhoon Seepage pressure Mutation factor Piezometric level

Limited value of procalcitonin,C-reactive protein,white blood cell,and neutrophil in detecting bacterial coinfection and guiding antibiotic use among children with enterovirus infection

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World Journal of Pediatrics 2022年第3期18卷 230-233页

作者： Rui-Mu Zhang Kun Tan shu fu Ji-Kui Deng Department of Infectious Diseases Shenzhen Children’s HospitalShenzhen 518038China

Procalcitonin(PCT),C-reactive protein(CRP),and white blood cell(WBC)have been used as markers of bacterial infection in children for *** studies have suggested PCT,CRP,WBC,and percentage of neutrophils(%N)may be useful in detecting bacterial infection in children[1-4].However,elevated levels of these biomarkers have also been noted in children with enterovirus infection[5-7].In a study involving 5692 hospitalized children with herpangina or hand,foot,and mouth disease(HFMD)in two periods of years,the medians of CRP were 50.1 and 42.5 mg/L,respectively.

关键词： enterovirus infection elevated

Microstructure and magnetic properties evolution of Al/CoCrFeNi nanocrystalline high-entropy alloy composite

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Rare Metals 2022年第6期41卷 2038-2046页

作者： Jun-Jie Wang Zong-De Kou shu fu Shang-shu Wu Si-Nan Liu Meng-Yang Yan Di Wang Si Lan Horst Hahn Tao Feng School of Material Science and Engineering Herbert Gleiter Institute of NanoscienceNanjing Universily of Science and TechnologyNanjing 210094China Institute of Nanotechnology Karlsruhe Institule of TechnologyKarlsruhe 76021Germany

A systematic microstructure-oriented magnetic property investigation for Al/CoCrFeNi nanocrystalline high-entropy alloys composite(nc-HEAC)is *** the initial state,the Al/CoCrFeNi nc-HEAC is composed of face-centered cubic(FCC)-Al,FCC-CoCrFeNi and hexagonal close-packed(HCP)-CoNi *** energy synchrotron radiation X-ray diffraction and high-resolution transmission electron microscopy were used to reveal the relationship between microstructure evolution and mag-netic mechanism of Al/CoCrFeNi nc-HEAC during heat *** low-temperature annealing stage,the mag-netic properties are mainly contributed by the HCP-CoNi *** the increase of temperature,the diffusion-in-duced phase transition process including the transformation of AlCoCrFeNi HEA from FCC to BCC structure and the growth of B2 phase plays a dominant role in the magnetic *** was found that the magnetic properties can be effectively regulated through the control of the thermal diffusion *** nano dual-phase thermal diffusion-induced phase transition behavior of nanocomposites pre-pared based on laser-IGC technology provides guidance for the diffusion process and microstructure evolution of two phases in composites.

关键词： Nanocry salline high-entropy alloy composites Diffusion-induced phase transition Magnetic Laser-inert gas condensation