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植物分类学报 2006年第1期44卷 86-88页

作者：杨平厚郎楷永西北农林科技大学林学院陕西杨凌712100 中国科学院植物研究所系统与进化植物学开放研究实验室北京100093

对中国陕西产的兰科新种太白山鸟巢兰***&***作了描述和绘图。本新种与尖唇鸟巢兰***相似,但整个植株为灰黑色,花序轴被贴伏银灰色长柔毛,萼片、花瓣和唇瓣灰黑色而边缘为灰白色,唇瓣宽倒卵形或近圆形,先端具短尖而不同。

关键词：乌巢兰属太白山鸟巢兰兰科新种陕西中国

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盾构管片设计改进惯用法模型及其内力解析解

岩土力学 2008年第1期29卷 161-166页

作者：侯公羽杨悦刘波中国矿业大学(北京)力学与建筑工程学院北京100083 黑龙江科技学院哈尔滨150027

管片设计一直是地铁设计中亟待解决的难题之一。管片计算模型的建立主要是考虑接头和土层抗力两种因素对结构的影响。对现有管片计算模型的接头简化进行了改进,推导了改进惯用法模型的内力和位移求解公式;并结合北京地铁10号线工程实例... 详细信息

管片设计一直是地铁设计中亟待解决的难题之一。管片计算模型的建立主要是考虑接头和土层抗力两种因素对结构的影响。对现有管片计算模型的接头简化进行了改进,推导了改进惯用法模型的内力和位移求解公式;并结合北京地铁10号线工程实例资料,对惯用法模型及改进模型进行了对比分析,与数值计算结果进行了综合验证分析。研究结果表明,推导的公式是可靠的,对地铁管片的设计和施工具有理论和实践意义。

关键词：管片内力改进惯用法模型接头刚度折减解析解

Pure quantum gradient descent algorithm and full quantum variational eigensolver

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Frontiers of physics 2024年第2期19卷 221-234页

作者： Ronghang Chen Zhou Guang Cong Guo Guanru Feng Shi-Yao hou College of Physics and Electronic Engineering Center for Computational SciencesSichuan Normal UniversityChengdu 610068China Shenzhen SpinQ Technology Co. Ltd.Shenzhen 518045China DEEPROUTE.AI

Optimization problems are prevalent in various fields,and the gradient-based gradient descent algorithm is a widely adopted optimization ***,in classical computing,computing the numerical gradient for a function with variables necessitates at least d+1 function evaluations,resulting in a computational complexity of O(d).As the number of variables increases,the classical gradient estimation methods require substantial resources,ultimately surpassing the capabilities of classical ***,leveraging the principles of superposition and entanglement in quantum mechanics,quantum computers can achieve genuine parallel computing,leading to exponential acceleration over classical algorithms in some *** this paper,we propose a novel quantum-based gradient calculation method that requires only a single oracle calculation to obtain the numerical gradient result for a multivariate *** complexity of this algorithm is just O(1).Building upon this approach,we successfully implemented the quantum gradient descent algorithm and applied it to the variational quantum eigensolver(VQE),creating a pure quantum variational optimization *** with classical gradient-based optimization algorithm,this quantum optimization algorithm has remarkable complexity advantages,providing an efficient solution to optimization *** proposed quantum-based method shows promise in enhancing the performance of optimization algorithms,highlighting the potential of quantum computing in this field.

关键词： quantum algorithm gradient descent variational quantum algorithm

Parallel-Data-Based Social Evolution Modeling

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Tsinghua Science and Technology 2021年第6期26卷 878-885页

作者： Weishan Zhang Zhaoxiang hou Xiao Wang Zhidong Xu Xin Liu Fei-Yue Wang China University of Petroleum Qingdao 266580China Qingdao Academy of Intelligent Industry Qingdao 266111China State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100049China Institute of National Security National Defense UniversityBeijing 100081China

Abnormal or drastic changes in the natural environment may lead to unexpected events,such as tsunamis and earthquakes,which are becoming a major threat to national ***,no effective assessment approach can deduce a situation and determine the optimal response strategy when a natural disaster *** this study,we propose a social evolution modeling approach and construct a deduction model for self-playing,self-learning,and self-upgrading on the basis of the idea of parallel data and reinforcement *** proposed approach can evaluate the impact of an event,deduce the situation,and provide optimal strategies for *** the breakage of a submarine cable caused by earthquake as an example,we find that the proposed modeling approach can obtain a higher reward compared with other existing methods.

关键词： paral el data reinforcement learning decision-making

Chloride-Promoted Photoelectrochemical C-H Silylation of Heteroarenes

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Chinese Journal of Chemistry 2023年第22期41卷 2963-2968页

作者： Xin-Ru Zhao Yu-Chen Zhang Zhong-Wei hou Lei Wang Advanced Research Institute and School of Pharmaceutical Sciences Taizhou UniversityJiaojiangZhejiang 318000China Department of Chemistry Huaibei Normal UniversityHuaibeiAnhui 235000China State Key Laboratory of Organometalic Chemistry Shanghai lnstitute of Organic ChemistryChinese Academy of SciencsShanghai200032China

A photoelectrochemical approach for the C-H silylation of heteroarenes through dehydrogenation cross-coupling with H2 evolution has been *** photoelectrochemical C-H silylation depends on hydrogen atom transfer(HAT)from silanes to Cl-radical generated through the light-induced homolytic cleavage of Cl2,in which Cl2 was produced by electrochemical oxidation of chloride.A large number of silylated heterocyclic molecules are rapidly constructed in satisfactory yields without relying on oxidants and metal reagents.

关键词： Photoelectrochemistry Silyl radicals C-H silylation Dehydrogenation N-Heterocycles Cross-coupling Oxidation

Deep learning for joint channel estimation and feedback in massive MIMO systems

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Digital Communications and Networks 2024年第1期10卷 83-93页

作者： Jiajia Guo Tong Chen Shi Jin Geoffrey Ye Li Xin Wang Xiaolin hou National Mobile Communications Research Laboratory Southeast UniversityNanjing210096China Department of Electrical and Electronic Engineering Imperial College LondonLondonSW72AZUK DOCOMO Beijing Communications Laboratories Co. LtdBeijingChina

The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base ***,the accurate CsI is difficult to obtain due to the large amount of feedback overhead caused by massive *** this paper,we propose a deep learning based joint channel estimation and feedback framework,which comprehensively realizes the estimation,compression,and reconstruction of downlink channels in FDD massive MIMO *** networks are constructed to perform estimation and feedback explicitly and *** explicit network adopts a multi-Signal-to-Noise-Ratios(SNRs)technique to obtain a single trained channel estimation subnet that works well with different SNRs and employs a deep residual network to reconstruct the channels,while the implicit network directly compresses pilots and sends them back to reduce network *** module is also designed to generate data-bearing *** results show that the two proposed networks exhibit excellent performance of reconstruction and are robust to different environments and quantization errors.

关键词： Channel estimation CSI feedback Deep learning Massive MIMO FDD

Effect of Al_(2)O_(3)/Na_(2)O ratio and MnO on high-temperature properties of mold flux for casting peritectic steel

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Journal of Iron and Steel Research International 2022年第1期29卷 53-60页

作者： Le-jun Zhou Hao Luo Wan-lin Wang Xiong Yan hou-fa Wu School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina National Center for International Cooperation of Clean Metallurgy Changsha 410083HunanChina

The influences of Al_(2)O_(3)/Na_(2)O ratio and MnO content on high-temperature properties,such as melting,crystallization,heat transfer,and viscosity of mold flux for casting peritectic steel,have been *** results show that the melting temperatures of mold flux decrease,whereas the ratio of crystalline layers increases with the decrease in Al_(2)O_(3)/Na_(2)O ratio and increase in MnO *** average response temperatures of the three mold fluxes decrease from 566,525,to 512℃,respectively,which indicates that the heat transfer controlling ability of mold flux is promoted due to the increase in crystallization ability and addition of transition metal oxide ***,the viscosity-temperature curves suggest that the viscosity at 1300℃ decreases,but the break temperature increases with the reduction in Al_(2)O_(3)/Na_(2)O and addition of MnO.

关键词： Mold flux Peritectic steel Melting Crystallization Heat transfer Viscosity

Unimolecular artificial transmembrane channel with terminal dihydrogen phosphate groups showing transport selectivity for ammonium

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Chinese Chemical Letters 2020年第1期31卷 77-80页

作者： Jian-Yu Chen Qi Xiao Harekrushna Behera Jun-Li hou Department of Chemistry Fudan University

A new artificial transmembrane channel molecule bearing dihydrogen phosphate groups has been *** terminal dihydrogen phosphate groups enable the channel to be highly negatively charged at both ends of the channel *** artificial channel could incorporate into the lipid bilayer efficiently under low *** channel displays high NH4+/K+selectivity due to the electrostatic interaction and hydrogen bonding between NH4+and the terminal dihydrogen phosphate groups.

关键词： Artificial transmembrane channel Ammonium transport Dihydrogen phosphate Pillararene Transmembrane transport Transport selectivity

左心疾病相关肺动脉高压患者血钠水平与住院时间的相关性研究

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中国全科医学 2025年第9期28卷 1065-1071页

作者：孙琳施熠炜侯晓敏郭耘廷赵旭董霖聂继盛秦小江山西医科大学公共卫生学院山西省太原市030001 山西医科大学第一医院山西省太原市030001 山西医科大学基础医学院山西省太原市030001

背景左心疾病相关肺动脉高压(PH-LHD)是肺动脉高压(PH)中较常见的一种。研究表明,血钠水平与1类PH的严重程度和不良预后相关,然而,其对PH-LHD的影响鲜有报道。目的探讨PH-LHD患者的血钠水平与N末端脑利钠肽前体(NT-proBNP)、超声心动图... 详细信息

背景左心疾病相关肺动脉高压(PH-LHD)是肺动脉高压(PH)中较常见的一种。研究表明,血钠水平与1类PH的严重程度和不良预后相关,然而,其对PH-LHD的影响鲜有报道。目的探讨PH-LHD患者的血钠水平与N末端脑利钠肽前体(NT-proBNP)、超声心动图指标的关系,评价血钠水平对PH-LHD严重程度及住院时间的影响,为PH-LHD患者的临床诊疗及提高医院周转率提供理论依据。方法回顾性收集2020年1月—2022年2月在山西医科大学第一医院住院的360例PH-LHD患者的临床资料,依据患者的中位血钠水平139 mmol/L(血钠<135 mmol/L为低血钠)将患者分为3组:血钠<135 mmol/L组(50例)、血钠135~139 mmol/L组(136例)、血钠140~145 mmol/L组(174例)。采用Spearman秩相关分析探讨血钠水平与住院时间、NT-proBNP及超声心动图指标的相关性;采用Kaplan-Meier生存曲线分析比较不同血钠水平PH-LHD患者的住院时间;采用二元Logistic回归分析探讨血钠水平对PH-LHD患者住院时间的影响。结果3组PH-LHD患者年龄、住院时间、NT-proBNP、左心房前后径、右心房面积、左心室射血分数、缩短分数比较,差异有统计学意义(P<0.05);其中血钠140~145 mmol/L组患者的住院时间、NT-proBNP低于血钠<135 mmol/L组及血钠135~139 mmol/L组(P<0.05)。Spearman秩相关分析结果显示,PH-LHD患者血钠水平与住院时间(r_(s)=-0.176)、NT-proBNP(r_(s)=-0.135)、右心室前后径(r_(s)=-0.110)、肺动脉收缩压(r_(s)=-0.105)均呈负相关(P<0.05)。Kaplan-Meier生存曲线分析结果显示,3组血钠水平的PH-LHD患者住院时间比较,差异有统计学意义(χ^(2)=12.469,P=0.002)。二元Logistic回归分析校正各控制变量后结果显示,血钠水平升高是PH-LHD患者住院时间延长的保护因素(OR=0.916,95%CI=0.859~0.977,P=0.008);与血钠140~145mmol/L患者相比,血钠<135 mmol/L(OR=2.268,95%CI=1.049~4.903,P=0.037)及血钠135~139 mmol/L(OR=2.056,95%CI=1.163~3.635,P=0.013)患者住院时间延长的风险均升高。结论血钠水平与PH-LHD严重程度密切相关,血钠水平降低是PH-LHD患者住院时间延长的独立危险因素,是一种潜在的治疗考虑因素,可为PH-LHD的诊疗及医院周转提供新策略。

关键词：肺动脉高压左心疾病相关肺动脉高压血钠超声心动图住院时间 Logistic模型

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证据理论组合公式的分析与改进

计算机工程 2005年第7期31卷 21-23页

作者：杨海峰侯朝桢北京理工大学自动控制系北京100081

在分析D-S证据组合公式所存在问题的基础上,根据将冲突质量合理地分配到造成冲突的各个假设或命题中去这一原则,提出了一种新的证据组合公式,仿真结果表明,其组合高冲突性证据的结果符合人的经验与直觉。

关键词：数据融合证据理论组合公式冲突性证据