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Journal of Hydrodynamics 2004年第1期16卷 34-38页

作者： DONGYu-hong luxi-yun ZHUANGLi-xian DepartmentofMechanicsandMechanicalEngineering UniversityofScienceandTechnologyofChinaHefeiAnhui230026China

Thermally-stratified shear turbulent channel flow with temperatureoscillation on the bottom wall of the channel was investigated with the Large Eddy Simulation (LES)approach coupled with dynamic Sub-Grid-Scale (SGS) models. The effect of temperature oscillation onthe turbulent channel flow behavior was examined. The phase-averaged velocities and temperature, andflow structures at different Richardson numbers and periods of the oscillation was analyzed.

关键词： large eddy simulation (LES) turbulent channel flow thermally-stratifiedturbulence sub-grid scale (SGS) model oscillatory heat transfer temperature oscillation

Prediction of fatal adverse prognosis in patients with fever-related diseases based on machine learning:a retrospective study

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Chinese Medical Journal 2020年第5期133卷 583-589页

作者： Chun-hong Zhao Hui-Tao Wu He-Bin Che Ya-Nan Song Yu-Zhuo Zhao Kai-Yuan Li hong-Ju xiao Yong-Zhi Zhai xin Liu hong-xi lu Tan-Shi Li Medical School of Chinese People’s Liberation Army Beijing 100853China Department of Emergency The First Medical Center of Chinese People’s Liberation Army General HospitalBeijing 100853China National Engineering Laboratory for Medical Big Data Application Technology The First Medical Center to Chinese People’s Liberation Army General HospitalBeijing 100853China

Background:Fever is the most common chief complaint of emergency *** identification of patients at an increasing risk of death may avert adverse *** aim of this study was to establish an early prediction model of fatal adverse prognosis of fever patients by extracting key indicators using big data ***:A retrospective study of patients’data was conducted using the Emergency Rescue Database of Chinese People’s Liberation Army General *** were divided into the fatal adverse prognosis group and the good prognosis *** commonly used clinical indicators were *** feature elimination method was used to determine the optimal number of the included *** the training model,logistic regression,random forest,adaboost,and bagging were *** also collected the emergency room data from December 2018 to December 2019 with the same inclusion and exclusion *** performance of the model was evaluated by accuracy,F1-score,precision,sensitivity,and the areas under receiver operator characteristic curves(ROC-AUC).Results:The accuracy of logistic regression,decision tree,adaboost and bagging was 0.951,0.928,0.924,and 0.924,F1-scores were 0.938,0.933,0.930,and 0.930,the precision was 0.943,0.938,0.937,and 0.937,ROC-AUC were 0.808,0.738,0.736,and 0.885,***-AUC of ten-fold cross-validation in logistic and bagging models were 0.80 and 0.87,*** top six coefficients and odds ratio(OR)values of the variables in the logistic regression were cardiac troponin T(CTnT)(coefficient=0.346,OR=1.413),temperature(T)(coefficient=0.235,OR=1.265),respiratory rate(RR)(coefficient=–0.206,OR=0.814),serum kalium(K)(coefficient=0.137,OR=1.146),pulse oxygen saturation(SPO2)(coefficient=–0.101,OR=0.904),and albumin(ALB)(coefficient=–0.043,OR=0.958).The weights of the top six variables in the bagging model were:CTnT,RR,lactate dehydrogenase,serum amylase,heart rate,and systolic blood ***

关键词： Fever Infection Machine learning Prognosis

Orbitronics for energy-efficient magnetization switching

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Science China(Information Sciences) 2025年第1期68卷 398-399页

作者： Yuxuan YAO Daoqian ZHU Qingtao xiA Jianing LIANG Yuhao JIANG Zhiyang PENG Jiaxu LI Chen xiAO Renyou XU Wenwen WANG xiantao SHANG Shiyang lu Dapeng ZHU hong-xi LIU Kaihua CAO Weisheng ZHAO Fert Beijing Institute School of Integrated Circuit Science and Engineering Beihang University National Key Lab of Spintronics Institute of International Innovation Beihang University Qingdao Research Institute Beihang University Truth Memory Corporation

Spin-orbit torque （SOT）,as a promising writing method for magnetic random-access memory （MRAM）,has garnered widespread interest for over a decade [1].Heavy metals,such as β-W,have been broadly adopted as spin current sources,but suffer from phase change at a limited thickness,resulting in a dramatic reduction of the charge-tospin conversion efficiency θSH[2].The thickness limitation leads to stringent etching conditions and large distribution among devices,posing challenges for simultaneously satisfying SOT efficiency,etching-stop margins,and back-end-ofline （BEOL） compatibility.

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Cross-subcarrier precoder design for massive MIMO-OFDM downlink with symplectic optimization

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Science China(Information Sciences) 2025年

作者： Yu-Xuan ZHANG An-An lu xiang-Gen xiA xi-Qi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Electrical and Computer Engineering University of Delaware

We propose a cross-subcarrier precoder design(CSPD) for massive multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) downlink. This work aims to significantly improve the channel estimation and signal detection performance by enhancing the smoothness of the frequency domain effective channel. This is accomplished by designing a few vectors known as the transform domain precoding vectors(TDPVs), which are then transformed into the frequency domain to generate the precoders for a set of subcarriers. To combat the effect of channel aging, the TDPVs are optimized under imperfect channel state information(CSI). The optimal precoder structure is derived by maximizing an upper bound of the ergodic weighted sum-rate(WSR) and utilizing the a posteriori beam-based statistical channel model(BSCM). To avoid the large-dimensional matrix inversion, we propose an algorithm with symplectic optimization. Simulation results indicate that the proposed cross-subcarrier precoder design significantly outperforms conventional methods.

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氯化钠水溶液管外沸腾换热的模拟实验研究

同济大学学报（自然科学版） 2002年第9期30卷 1051-1055页

作者：李茂德熊丽红卢希红同济大学热能工程系上海200092

基于传热学实验研究的相似理论 ,对溴化锂吸收式制冷机高压发生器中常用的光管和外螺纹管的沸腾换热过程用氯化钠水溶液进行了模拟实验研究 ,得到了管壁面过热温度为 2～ 7℃和热流密度为 1～ 2 0kW·m-2下 ,光管和外螺纹管核态沸腾对... 详细信息

基于传热学实验研究的相似理论 ,对溴化锂吸收式制冷机高压发生器中常用的光管和外螺纹管的沸腾换热过程用氯化钠水溶液进行了模拟实验研究 ,得到了管壁面过热温度为 2～ 7℃和热流密度为 1～ 2 0kW·m-2下 ,光管和外螺纹管核态沸腾对流换热的实验数据 (包括在纯水、不同质量分数的氯化钠水溶液、单管光管、三管光管、单管螺纹管和三管螺纹管之间八种组合的沸腾热换工况 ) .通过将实验结果进行数据处理 ,并与溴化锂溶液沸腾换热工况的数据进行相似性比较和分析以后发现 ,结果吻合良好 .由此可知 ,通过调整和扩大模拟实验的范围 ,可以得到大量的模拟实验数据 .将这些实验数据稍作修整即可直接应用于溴化锂吸收式制冷机换热设计计算或校核计算过程 .

关键词：氯化钠水溶液沸腾换热模拟试验外螺纹管光管传热学对流换热

海洋经济发展背景下海洋类高校职业文化建设研究

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浙江海洋学院学报（人文科学版） 2017年第3期34卷 75-79页

作者：曹虹芦茜王征浙江海洋大学人文学院教师教育学院浙江舟山316022 浙江海洋大学学工部浙江舟山316022

本文从海洋强国的整体格局和海洋经济发展需求出发,探索和研究海洋类高校的职业文化,将对区域海洋经济的发展、高校海洋类人才培养、涉海类企业的人才需求和提升海洋类大学生个体成长的职业发展竞争力等都具有十分重要的意义。然从调查... 详细信息

本文从海洋强国的整体格局和海洋经济发展需求出发,探索和研究海洋类高校的职业文化,将对区域海洋经济的发展、高校海洋类人才培养、涉海类企业的人才需求和提升海洋类大学生个体成长的职业发展竞争力等都具有十分重要的意义。然从调查的现实情况来看,海洋类高校职业文化存在职业文化认知的模糊化、职业文化教育的碎片化、职业文化内容的简单化和职业文化队伍的边缘化四大现状。因此,构建"海洋特色文化元素+"思维模式、"涉海类企业文化要素+"双赢模式、"海洋传统文化+"生态模式、"企业人才+"合力育人模式的海洋经济特色的高校职业文化,是海洋类高校加强职业文化建设的有益尝试,也是提升海洋类高校服务区域经济功能的积极探索。

关键词：海洋经济海洋类高校职业文化

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北京和东北地区雷暴与太阳活动的关系

空间科学学报 1986年第1期 52-59页

作者：庄洪春吕锡从中国科学院空间物理研究所中国科学院空间物理研究所

太阳活动对于大气电性能可能会产生影响,而大气电性能在雷暴形成过程中可能会起着重要作用.因此,太阳活动对于大气电性能的影响,最终将有可能影响到雷暴的形成.本文用1957年到1978年北京地区和东北地区的10个气象站的13000多个雷暴资料... 详细信息

太阳活动对于大气电性能可能会产生影响,而大气电性能在雷暴形成过程中可能会起着重要作用.因此,太阳活动对于大气电性能的影响,最终将有可能影响到雷暴的形成.本文用1957年到1978年北京地区和东北地区的10个气象站的13000多个雷暴资料,用时序迭加法分析了雷暴数与太阳磁扇形界面通过、太阳耀斑及太阳黑子11年周期变化等的关系.结果表明,有些年分的雷暴数当行星际磁场方向由指向太阳变为离开太阳的磁扇形界面扫过地球时有相关影响,在界面通过前后3天内或7天后雷暴数明显增大.从季节来看,上半年的界面通过比下半年的界面通过对雷暴的影响大.在各种太阳耀斑分类统计分析中,看到出现在日面上西区特别是西一区(0°-30°)的耀斑对雷暴的影响显著.雷暴数与太阳黑子11年周期变化则没有很显著的相关关系.

关键词：太阳活动大气电行星际磁场磁扇形周期变化日面气象台站地球时扫过统计分析

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腹腔镜与腹式大子宫全切除术的对比分析

中国妇幼保健 2012年第13期27卷 1965-1967页

作者：王海波闫西红逯彩虹李萍周爱玲孟宪涛李保红解放军260医院妇产科河北石家庄050041

目的:比较腹腔镜和腹式大子宫全切除术的手术时间、术中出血量和术后病率,探讨腹腔镜下大子宫切除术的安全性和可行性。方法:回顾分析该院2007年1月～2010年1月大子宫切除术300例的临床资料,其中开腹150例,腹腔镜150例,对比分析两种术... 详细信息

目的:比较腹腔镜和腹式大子宫全切除术的手术时间、术中出血量和术后病率,探讨腹腔镜下大子宫切除术的安全性和可行性。方法:回顾分析该院2007年1月～2010年1月大子宫切除术300例的临床资料,其中开腹150例,腹腔镜150例,对比分析两种术式术中、术后各项参数。结果:腹腔镜组手术时间长于开腹组,差异有统计学意义(P<0.05),术中出血量明显少于开腹组,差异有统计学意义(P<0.05),腹腔镜组术后肛门排气时间、术后病率明显低于开腹组,差异有统计学意义(P<0.01)。结论:改良后的腹腔镜下大子宫全切术是安全可行的,该术式微创,对腹腔干扰小,术后病率低。

关键词：腹腔镜大子宫子宫全切除术手术治疗

A novel current-sharing scheme based on magamp

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1150-1156页

作者： Wen-xi YAO xiao-yuan hong Zheng-yu lu School of Electrical Engineering Zhejiang University Hangzhou 310027 China

The magamp (magnetic amplifier) is widely used in power supplies due to its low cost, simplicity and other advan-tages. This paper discusses a novel application of the magamp in switching power supplies, where the magamp is used to regulate pulse width modulation (PWM) instead of power signal in the main circuit. This method extends the application of the magamp in power supplies, and makes it possible to further regulate control signal when PWMs have been generated. Based on this applica-tion, a new current-sharing (CS) scheme using the magamp is proposed, which uses a modified inner loop CS structure. In this scheme PWMs are generated by one main controller, and CS is achieved by regulating PWMs using a magamp in each module. Compared with traditional application of the magamp, the new CS scheme can be used in most topologies and only requires magamps of low power capacity. Then a test circuit of parallel power supply is developed, in which CS is achieved by a PWM regulator with the magamp. The proposed scheme is also used to upgrade an electroplate power to make it capable of paralleling supplies. Experimental results show that the proposed scheme has good CS performance.

关键词： Current-sharing (CS) Magnetic amplifier (magamp) Parallel

Hamiltonian Forms for a Hierarchy of Discrete Integrable Coupling Systems

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Communications in Theoretical Physics 2008年第12期50卷 1269-1275页

作者： XU xi-xiang YANG hong-xiang lu Rong-Wu College of Science Shandong University of Science and Technology Qingdao 266510 China Department of Information Science and Technology Taishan College Tai＇an 271021 China

A semi-direct sum of two Lie algebras of four-by-four matrices is presented,and a discrete four-by-fourmatrix spectral problem is introduced.A hierarchy of discrete integrable coupling systems is *** obtainedintegrable coupling systems are all written in their Hamiltonian forms by the discrete variational ***,we prove that the lattice equations in the obtained integrable coupling systems are all Liouville integrable discreteHamiltonian systems.

关键词： integrable lattice equation semi-direct sum of Lie algebra integrable coupling system discrete variational identity Hamiltonian form Liouville integrability