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BER analysis of MPSK space-time code with differential detection over correlated block-fading Rayleigh channel

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 18-25页

作者： zou yu-long ZHENG Bao-yu Institute of Signal Processing and Transmission Nanjing University of Postsand Telecommunications Nanjing 210003 China

MIMO technology proposed in recent years can effectively combat the multipath fading of wireless channel and can considerably enlarge the channel capacity, which has been investigated widely by researchers. However, its performance analysis over correlated block-fading Rayleigh channel is still an open and challenging objective. In this article, an analytic expression of bit error rate （BER） is presented for multiple phase shift keying （MPSK） space-time code, with differential detection over correlated block-fading Rayleigh channel. Through theoretical analysis of BER, it can be found that the differential space-time scheme without the need for channel state information （CSI） at receiver achieves distinct performance gain compared with the traditional nonspace-time system. And then, the system simulation is complimented to verify the above result, showing that the diversity system based on the differential space-time block coding （DSTBC） outperforms the traditional nonspacetime system with diversity gain in terms of BER. Furthermore, the numerical results also demonstrate that the error floor of the differential space-time system is much lower than that of the differential nonspace-time system.

关键词： differential space-time block code correlated blockfading Rayleigh channel CSI error floor

THEORETICAL XUV SPECTRA FROM CARBON-LIKE COBALT IONS BY RELATIVISTIC CONFIGURATION INTERACTION CALCULATION

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Chinese Physics Letters 1990年第5期7卷 216-218页

作者： zou yu LI Jiaming Institute of Applied Physics and Computation Mathmatics Beijing 100080 Institute of Physics Academia SinicaBeijing 100080

Allowed Δn=0 transitions of highly ionized metal atoms,which may appear in the solar spectra as well as in spectra from the high-temperature tokamak plasmas,lie in the extreme vacuum UV(XUV) region,100A≤λ≤*** we report our theoretical calculation of the Δn=0 transitions of C-like cobalt ions;it is in good agreement with the experimental *** theoretical calculations of the transition wave lengths and their oscillator strengths should be very helpful to identify the XUV spectra.

关键词： spectra measurement transitions

Cold Spray Additive Manufacturing:Microstructure Evolution and Bonding Features

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Accounts of Materials Research 2021年第11期2卷 1071-1081页

作者： yu zou Department of Materials Science and Engineering University of TorontoTorontoON M5S 3E4Canada

CONSPECTUS:Most metal additive manufacturing(AM)methods involve the melting or sintering of feedstock powder or wire using an energy source(laser,electron beam,or electric arc).Solid-state AM,sometimes also known as non-beam-based AM,is a process in which the deposited material does not melt and is built up layer-by-layer,typically through severe plastic *** considered to be a coating technique,by virtue of its high deposition rate,cold spray additive manufacturing(CSAM)is attractive as a solid-state AM *** the CSAM process,metal powder particles are impacted onto a substrate at a supersonic velocity and relatively low *** CSAM process reduces or eliminates many problems associated with melting or beambased AM methods,making the CSAM technically attractive for a wide range of applications,such as in the aerospace,automobile,marine,biomedical,machinery,and energy sectors.

关键词： Microstructure coating attractive

Relativistic Multichannel Theory:Theoretical Studies of Excited Energy Structure of Ar Atom

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Chinese Physics Letters 1995年第6期12卷 351-354页

作者： TONG Xiaomin zou yu LI Jiaming Institute of Physics Academia SinicaBeijing 100080

We here present a relativistic multichannel theory which can be regarded as an extension of traditional configuration interaction theories by including continuum configuration *** relativistic multichannel theory aims directly to calculate the compact set of physical parameters(μ_(α),U_(iα)) in multichannel quantum defect *** Ar atom as an example,we compare our calculated orbital energies with traditional configuration interaction calculations as well as experimental measurements.

关键词： theory. configuration relativistic

Properties and processing technologies of high-entropy alloys

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Materials Futures 2022年第2期1卷 9-20页

作者： Xuehui Yan yu zou Yong Zhang Beijing Advanced Innovation Center of Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Department of Materials Science and Engineering University of Toronto184 College StTorontoON M5S 3E4Canada

High-entropy alloys (HEAs) are emerging materials that are developed based on entropy, anddraw significant attention for the potential to design their chemical disorder to bring outdifferent structural and physical characteristics. Over the past two decades, significant salientefforts have been conducted to explore many unique and useful properties of HEAs, such asovercoming the strength–ductility trade-off, outstanding thermal stability, and excellent lowtemperature plasticity. Here, we review the key research topic of HEAs in the following threeaspects: (a) performance advantages and composition design, (b) performance-driven HEAs and(c) fabrication process-driven HEAs. Towards their industrial applications, our article reviews alarge range of methods to synthesise, fabricate and process HEAs. We also discuss the currentchallenges and future opportunities, mainly focusing on performance breakthroughs in HEAs.

关键词： high-entropy alloys review order and disorder properties processing

Coffee drinking and pancreatic cancer risk:A meta-analysis of cohort studies

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World Journal of Gastroenterology 2011年第9期17卷 1204-1210页

作者： Jie Dong Jian zou Xiao-Feng yu Department of Gastroenterology Huadong Hospital Fudan University Shanghai200040 China

AIM:To quantitatively assess the relationship between coffee consumption and incidence of pancreatic cancer in a meta-analysis of cohort studies. METHODS:We searched MEDLINE,EMBASE,Science Citation Index Expanded and bibliographies of retrieved *** were included if they reported relative risks(RRs)and corresponding 95%CIs of pancreatic cancer with respect to frequency of coffee *** performed random-effects meta-analyses and metaregressions of study-specific incremental estimates to determine the risk of pancreatic cancer associated with a 1 cup/d increment in coffee consumption. RESULTS:Fourteen studies met the inclusion criteria, which included 671 080 individuals(1496 cancer events) with an average follow-up of 14.9 *** with individuals who did not drink or seldom drank coffee per day,the pooled RR of pancreatic cancer was 0.82 (95%CI:0.69-0.95)for regular coffee drinkers,0.86 (0.76-0.96)for low to moderate coffee drinkers,and 0.68(0.51-0.84)for high *** subgroup analyses,we noted that,coffee drinking was associated witha reduced risk of pancreatic cancer in men,while this association was not seen in *** associations were also similar in studies from North America,Europe, and the Asia-Pacific region. CONCLUSION:Findings from this meta-analysis suggest that there is an inverse relationship between coffee drinking and risk of pancreatic cancer.

关键词： Coffee Cohort study Meta-analysis Pancreatic neoplasm

Dielectronic Recombination on He+ with Non-isolated Resonance Approach

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Chinese Physics Letters 2000年第2期17卷 96-98页

作者： zou yu ZHAO LI-Bo FANG quan-yu Institute of Applied Physics and Computational Mathematics Beijing 100088 Department of Applied Physics Beijing University of Aeronautics and AstronauticsBeijing 100083

Based on the relativistic multichannel theory, a non-isolated resonance approach has been developed to calculate the cross sections of dielectronic recombination on He+ for △n=1 and 2 transitions. A first order approximation is adopted for the radiative process. The convolved cross sections for the n≤3 states in both transitions are in good agreement with those of the observations. It is shown that the l-dependence of the field ionization and the radiative decay during the time-of-flight affect significantly the measurement of the cross sections near the initial state of the field ionization.

关键词： process transitions radiative

Relativistic Multichannel Theory:Scaling Behavior of Multichannel Quantum Defect Theory Parameters(μ_(α),U_(iα)) Along the Ne-Like Iso-electronic Sequence

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Chinese Physics Letters 1996年第4期13卷 269-272页

作者： zou yu TONG Xiao-min LI Jia-ming Institute of Physics Chinese Academy of SciencesBeijing 100080 Institute of Applied Physics and Computational Mathematics Beijing 100088

The compact physical parameters(μ_(α),U_(iα))in multichannel quantum defect theory(MQDT)can be directly calculated with relativistic multichannel theory(RMCT).Here we report a systematic study of the MQDT parameters(fiay Uia)with RMCT along the Ne-like iso-electronic sequence(including Ca^(10+),Fe^(16+),Ge^(22+),Ag^(37+) ions).We find that the physical parameters(μ_(α),U_(iα))show a very interesting scaling behavior along the iso-electronic sequence.

关键词： electronic MQDT scaling

云南省2020-2023年卫生资源发展状况分析

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卫生软科学 2025年第1期39卷 62-66页

作者：杨霞高峰邹钰范爽云南省健康医疗大数据中心云南昆明650118 云南省健康发展研究中心云南昆明650031

[目的]对云南省2020-2023年的卫生资源状况进行分析,为合理配置卫生资源、促进全省卫生健康事业发展提供参考。[方法]通过对2020-2023年云南省医疗卫生机构数、床位及人员等数据进行汇总分析,与全国、西部平均水平、“十四五”规划要求... 详细信息

[目的]对云南省2020-2023年的卫生资源状况进行分析,为合理配置卫生资源、促进全省卫生健康事业发展提供参考。[方法]通过对2020-2023年云南省医疗卫生机构数、床位及人员等数据进行汇总分析,与全国、西部平均水平、“十四五”规划要求进行对比。[结果]2020-2023年,云南省医疗卫生机构数从2020年的26,626个增加到2023年的28,768个,卫生人员从2020年的45.89万人增加到2023年的51.27万人,其中卫生技术人员从36.65万人增加到42.52万人;床位数从2020年的32.52万张增加到2023年的35.99万张。到2023年,每千人口医疗卫生机构床位数、执业(助理)医师数、注册护士数及每万人口全科医生数、公共卫生机构人员数分别为7.7张、3.14人、4.36人以及3.39人、8.6人。[结论]2020-2023年云南省各类卫生资源明显增加,卫生人力资源、床位资源增长较快,已逐步接近或超过“十四五”规划目标。但机构间发展不均衡,不同机构的病床使用情况存在差异,建议优化床位资源配置,继续加强执业(助理)医师、药师、公共卫生人员队伍建设,逐步促进机构间均衡发展。

关键词：卫生资源医疗卫生机构卫生人员床位十四五云南