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A novel 3D frequency domain SAGE algorithm with applications to parameter estimation in mm Wave massive MIMO indoor channels

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Science China(Information Sciences) 2017年第8期60卷 58-69页

作者： Rui feng Jie HUANG jian SUN Cheng-Xiang WANG Shandong Provincial Key Laboratory of Wireless Communication Technologies Shandong University State Key Laboratory of Millimeter Waves Southeast University Institute of Sensors Signals and Systems School of Engineering & Physical Sciences Heriot-Watt University

Millimeter wave(mm Wave) and massive multiple-input multiple-output(MIMO) wireless communication channels show some new characteristics different from conventional channels. In order to have an in-depth understanding of mm Wave massive MIMO channels, we conduct channel measurements at 16, 28, and 38 GHz frequency bands using virtual large horizontal planar arrays in an indoor office environment. First, a three dimensional(3D) frequency domain(FD) parameter estimation algorithm extended from the space alternating generalized expectation-maximization(SAGE) algorithm is proposed and used to process the measurement ***, by dividing the large array into several sub-arrays and calculating power delay profiles(PDPs), power azimuth angle profiles(PAAPs), and power elevation angle profiles(PEAPs), we analyze the changes of delay,azimuth angle of arrival(AAo A), and elevation Ao A(EAo A) over the large array. We find that the spatial cross-correlation functions(SCCFs) calculated along different directions of the planar array exhibit significant variations. Third, the comparison of the averaged PDPs(APDPs) at three different frequency bands shows that the attenuation increases when mm Wave channels move to high frequency bands. Furthermore, SCCFs of channels at three frequency bands are also compared for two uniform linear arrays(ULAs). We draw conclusion that the correlation coefficients can be affected by not only measurement environments, but also the relative angle between transmitter(Tx) pointing direction and receiver(Rx) large array, and the operating frequency bands.

关键词： millimeter wave bands massive MIMO 3D FD-SAGE algorithm planar array statistical properties

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Degradation of organics using LaFeO_(3)as a persulfate activator under low-intensity ultra-violet-light irradiation:Catalytic performance and mechanism

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Journal of Rare Earths 2022年第7期40卷 1043-1052页

作者： Yumei Li jian Fan Xiaonan feng Tao Tao School of Environment Huazhong University of Science and TechnologyWuhan 430074China School of Energy and Environment Inner Mongolia University of Science and TechnologyBaotou 014010China

ABO_(3)-type perovskite oxides with abounding defect structures and diverse physical chemistry attributes have been extensively studied in heterogeneous *** LaFeO_(3)perovskites fabricated via the sol-gel method were used as peroxydisulfate(PDS)activators for methylene blue(MB)degradation under low-intensity ultra-violet(UV)-light to evaluate the degradation efficiency of organic pollutants and *** results indicate that under low-intensity UV irradiation,the developed UV/LaFeO_(3)/PDS system shows excellent degradation ability of organic pollutants in a wide pH *** spin resonance and radical quenching experiments verify that SO_(4)^(·-),·OH,h^(+)and ^(1)O_(2)are generated during the activation process,and ^(1)O_(2)plays a dominant role in MB *** of low oxidation state Fe(Ⅱ)and O_(2)^(2-)/O^(-)on the LaFeO_(3)surface shows that oxygen vacancy,as the electron transfer mediator,enhances the redox cycle efficiency of Fe(Ⅱ)/Fe(Ⅲ).Photogenerated electrons of LaFeO_(3)involved in the cyclic transformation of Fe(Ⅱ)/Fe(Ⅲ)and PDS activation further increase the number of active radicals and thus promote the synergistic effect of photocatalytic coupled with sulfate radicalbased advanced oxidation processes.

关键词： LaFeO_(3) Peroxydisulfate Singlet oxygen Low-intensity UV-light Rare earths

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AWells-Riley/based COVID-19 infectiousrisk assessment model combining both short rangeandroom scale effects

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Building Simulation 2024年第1期17卷 93-111页

作者： Yinshuai feng Yifan Fan Xiaoyu Luo jian Ge College of Civil Engineering and Architecture Zhejiang UniversityHangzhouChina Center for Balance Architecture Zhejiang UniversityHangzhouChina International Research Center for Green Building and Low-Carbon City International CampusZhejiang UniversityHainingChina

There is growing evidence of the high transmission potential of COVID-19 through virus-laden *** aerosols are inhaled in various concentrations,an overall assessment of transmission risks at different indoor scales is ***,a comprehensive risk assessment method that evaluates the direct link between short-range and room-scale zones is stl *** this paper,a risk assessment model combining both short-range and room-scale effects is developed to obtain effective reproduction number in confined indoor environments,called Turbulent Jet Wells Riley(TJWR)*** with the viral load data and aerosol generation data of different human respiratory activities,the Monte Carlo simulation method is applied to calculate the quanta emission rate,which further provides the input parameters of the TJWR *** known outbreaks(Hangzhou banquet hall X,Guangzhou restaurant Y,and Hong Kong restaurant Z,China)are chosen to validate the TJWR *** show that the TJWR model is more efficient than the original Wells-Riley *** average relative error of the TJWR model ranges between 9%and 44%,while for the Wells-Riley model,it ranges between 57%and 78%.The TJWR model also proves that infection risk assessments using the well-mixed assumption can systematically underestimate the transmission risk for those close to the ***,there is a significant positive linear correlation between the total number of exposed individuals at the short-range and the effective reproduction *** newly developed TJWR model has great potential for rapid and real-time overall airborne transmission risk assessment in buildings and cities.

关键词： COVID-19 airborne transmission infection risk Wells-Riley model Monte Carlo simulation

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Quantum Mechanics Version of Wavelet Transform Studied by Virtue of IWOPTechnique

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Communications in Theoretical Physics 2004年第5期41卷 681-684页

作者： FANHong-Yi Lǖjian-feng DepartmentofPhysics ShanghaiJiaoTongUniversityShanghai200030China

Using the technique of integral within an ordered product (IWOP) of operators we show that the wavelet transform can be recasted to a matrix element of squeezing-displacing operator between the mother wavelet state vector and the state vector to be transformed in the context of quantum mechanics. In this way many quantum optical states'wavelet transform can be easily derived.

关键词： wavelet transform IWOP technique squeezing-displacing operator

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DNA-guided genome editing tool

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Science China(Life Sciences) 2016年第7期59卷 740-741页

作者： Dandan Zhang jian-feng Li Key Laboratory of Gene Engineering of the Ministry of Education State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant Resources School of Life Sciences Sun Yat-sen University

Technologies for targeted modification of eukaryotic genomes are of great value for elucidating and manipulating gene functions in fundamental and applied biological *** the past two decades,genome editing tools have evolved quickly from random DNA mutagenesis-inducing chemicals or ionizing radiation to programmable sequencespecific nucleases(SSNs)with the CRISPR/Cas technology as the most significant breakthrough(Gaj et al.,2013).

关键词：编辑工具基因组 DNA 引导序列特异性搜索技术基本操作改性过程

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Model and simulation of four-wheeled robot based on Mecanum wheel

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International Journal of Modeling, Simulation, and Scientific Computing 2017年第2期8卷 124-138页

作者： jianwei Zhao Yuanshuang Liu Yuanyuan Qu feng Bian Yu ban School of Mechanical Electronic and Information Engineering China University of Mining and Technology(Beijing)Beijing 100083 P.R.China

Based on Mecanum wheels and“Y”-shaped planetary wheels,we combine these two kinds of wheels’respective motion principle with their advantages to design a new type of four-wheeled robot:install the Mecanum wheels at the end of“Y”-shaped planetary wheel *** wheel designed based on Mecanum wheels and“Y”-shaped planetary wheel can adapt to the complex terrain such as stairs,steps,and at the same time it can achieve the rotation of the whole body in a limited *** paper studies the adaptability of the four-wheeled robot to the stairs,analyzing and calculating the parameters of the four-wheeled robot and the stairs.

关键词： Four-wheeled robot Mecanum wheel “Y”-shaped planetary wheel obstacle avoidance.

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Ellagic acid inhibits gastric cancer cells by modulating oxidative stress and inducing apoptosis

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Asian Pacific Journal of Tropical Biomedicine 2024年第4期14卷 162-169页

作者： jian Zheng Chun-feng Li Department of Diagnostic Radiology Division Harbin Medical University Cancer HospitalHeilongjiangChina Department of Gastrointestinal Surgical Ward Harbin Medical University Cancer HospitalHeilongjiangChina

Objective:To evaluate the anticancer effect of ellagic acid on gastric cancer ***:MTT assay was used to evaluate the effect of ellagic acid at different concentrations(0.5-100μg/mL)on gastric cancer AGS ***-qPCR and Western blot analyses were applied to assess apoptosis(BCL-2,CASP-3,and BAX)and autophagy(LC3,ATG5,and BECN1)in AGS cells treated with ellagic *** expression of invasion-related markers including TP53,CDKN2A,and PTEN was *** addition,cell cycle markers including cyclin A,B,D,and E were measured by *** stress markers were evaluated using ***:Ellagic acid inhibited the proliferation of AGS cells in a concentration-and time-dependent *** expression of BCL-2 was significantly decreased(P0.05).Moreover,the oxidative stress markers including SOD,TAC,and MDA were increased by ellagic acid(P<0.01).Conclusions:Ellagic acid can inhibit cell proliferation,induce apoptosis,and modulate oxidative stress in AGS ***,further in vivo and molecular studies are needed to verify its anticancer efficacy.

关键词： Ellagic acid Gastric cancer Apoptosis Autophagy Metastasis Proliferation

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Effects of Exogenous Silicon on Photosynthetic Capacity and Antioxidant Enzyme Activities in Chloroplast of Cucumber Seedlings Under Excess Manganese

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Agricultural Sciences in China 2009年第1期8卷 40-50页

作者： feng jian-peng SHI Qing-hua WANG Xiu-feng College of Horticultural Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R.China State Key Laboratory of Crop Biology Tai＇an 271018 P.R.China

Effects of silicon on photosynthetic parameters and antioxidant enzymes of chloroplast in cucumber seedlings under excess Mn were studied. Compared with the control, excess Mn significantly inhibited net photosynthetic rate （Pn）, stomatal conductance, as well as the maximum yield of the photosystem II photochemical reactions （Fv/Fm） and the quantum yield of photosysytem II electron transport （Φ PSII）, application of Si reversed the negative effects of excess Mn. In the further investigation, it was obtained that application of Si significantly increased the activities of enzymes related with ascorbate-glutathione cycle including ascorbate peroxidase （APX）, dehydroascorbate reductase （DHAR） and glutathione reductase （GR） in cucumber chloroplast under excess Mn, this could be responsible for the lower accumulation of H2O2 and lower lipid peroxidation of chloroplast induced by Mn, and resulted in keeping higher photosynthesis.

关键词： cucumber excess manganese photosynthesis chlorophyll fluorescence chloroplast antioxidant enzymes

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A Padé-Aided Analysis of Nonperturbative NN Scattering in ^1S0 Channel

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Communications in Theoretical Physics 2007年第4期47卷 699-704页

作者： YANG Ji-feng HUANG jian-Hua Department of Physics East China Normal University Shanghai 200062 China

We carried out a Padé approximant analysis on a compact factor of the T-matrlx for NN scattering to explore the nonperturbative renormalization prescription in a universal manner. The utilities and virtues for this ... 详细信息

关键词： nucleon-nucleon interactions nonperturbative renormalization Padé approximent

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Protein S-Nitrosylation in plants: Current progresses and challenges

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Journal of Integrative Plant Biology 2019年第12期61卷 1206-1223页

作者： jian feng Lichao Chen jianru Zuo Sainsbury Laboratory University of CambridgeCambridge CB21LRUK State Key Laboratory of Plant Genomics and National Center for Plant Gene Research CAS Center for Excellence in Molecular Plant SciencesInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China The University of Chinese Academy of Sciences Beijing 100049China

Nitric oxide(NO)is an important signaling molecule regulating diverse biological processes in all living organisms.A major physiological function of NO is executed via protein S-nitrosylation,a redox-based the past decade,significant progress has been made in functional characterization of S-nitrosylated proteins Inviteposttranslational modification by covalently adding a NO molecule to a reactive cysteine thiol of a target protein.S-nitrosylation is an evolutionarily conserved mechanism modulating multiple aspects of cellular *** *** evidence indicates that protein Snitrosylation is ubiquitously involved in the regulation of plant development and stress *** we review current understanding on the regulatory mechanisms of protein S-nitrosylation in various biological processes in plants and highlight key challenges in this field.

关键词： field. adding conserved

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