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比特交织随机分层空时码的Turbo检测—译码方法

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通信学报 2006年第6期27卷 102-107,114页

作者：李小玮陈芳炯韦岗华南理工大学电子与信息学院广东广州510640

对于一种采用比特交织的随机分层结构的空时码,提出了一种应用Turbo原理的迭代检测—译码方法,新方法基于软干扰消除的BLAST检测和卷积码的SISO(softinputsoftoutput)译码,通过交换检测器和译码器之间的软信息,为迭代处理提供新的软信... 详细信息

对于一种采用比特交织的随机分层结构的空时码,提出了一种应用Turbo原理的迭代检测—译码方法,新方法基于软干扰消除的BLAST检测和卷积码的SISO(softinputsoftoutput)译码,通过交换检测器和译码器之间的软信息,为迭代处理提供新的软信息。新方法大大提高了系统的性能,计算机仿真结果和计算复杂度分析显示了新方法的应用潜力。

关键词：多入多出随机分层空时码比特交织 Turbo检测-译码软信息

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刍议农村社区建设

经济问题 2010年第9期 100-103页

作者：李小伟山西省社会科学院社会学研究所太原030006

农村社区建设的提出为解决农村社会发展严重滞后和农村治理方式的转变找到了切入点,农村社区建设面临着历史的发展机遇。同时,由政府主导的农村社区建设,在农村现有的治理体制所形成的基本社会秩序下面临发展困境。为此,必须变政府主导... 详细信息

农村社区建设的提出为解决农村社会发展严重滞后和农村治理方式的转变找到了切入点,农村社区建设面临着历史的发展机遇。同时,由政府主导的农村社区建设,在农村现有的治理体制所形成的基本社会秩序下面临发展困境。为此,必须变政府主导为引导,在这一发展模式下重新定位农村社区的功能,确定社区建设的内容,把握社区建设的内涵,走出农村社区发展的困境。

关键词：农村社区困境治理

Relationships between perceived social support and retention patients receiving methadone maintenance treatment in China mainland

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Chinese Nursing Research 2016年第1期3卷 11-15页

作者： Kai-Na Zhou Heng-Xin li xiao-li wei xiao-Mei li Gui-Hua Zhuang Department of Nursing Xi'an Jiaotong University Health Science CenterXi'anShaanxi 710061China iaotong University Health Science Center Xi'anShaanxi 710061China Xi'an Center for Disease Control and Prevention Xi'anShaanxi 710054China

Objective： The purpose of this study was to explore the relationships between perceived social support and retention in Chinese mainland patients receiving methadone maintenance treatment （MMT）. Methods： This was a cross-sectional two-year follow-up study. The data collected included patients＇ baseline characteristics, perceived social support and retention in MMT. Results： A total of 1212 patients completed the cross-sectional survey; 809 （66.7%） had good perceived social support and 458 （3Z8~） had experienced readmissions. With and without controlling for baseline characteristics, past retention had no significant influence on perceived social support. By the end of the follow-up, 527 （43.5%） patients had terminated MMT. The patients without good perceived social support were more likely to terminate treatment than those with good perceived social support [hazard ratio： 1.31, 95% confidence interval： 1.10, 1.57; 1.25 （1.04,1.51 ）] regardless of their baseline characteristics and past retention. Conclusions： Retention, thus, had no significant influence on perceived social support in MMT, whereas good oerceived social suooort was a stron~ orotective oredictor of retention.

关键词： Perceived social supportRetentionMethadoneMaintenance treatmentRelationship

Effect of Optimized Concentrations of Basic Fibroblast Growth Factor and Epidermal Growth Factor on Proliferation of Fibroblasts and Expression of Collagen： Related to Pelvic Floor Tissue Regeneration

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Chinese Medical Journal 2018年第17期131卷 2089-2096页

作者： Yuan-Yuan Jia Jing-Yi Zhou Yue Chang Fang An xiao-wei li xiao-Yue Xu Xiu-li Sun Chun-Yang Xiong Jian-liu Wang Department of Obstetrics and Gynecology Peking University People's Hospital Beijing 100044 China Beijing Key Laboratory of Female Pelvic Floor Disorders Beijing 100044 China Department of Mechanics and Bioengineering College of Engineering Peking University Beijing 100871 China

Background： Fibroblasts were the main seed cells in the studies of tissue engineering of the pelvic floor ligament. Basic fibroblast growth factor （bFGF） and epidermal growth factor （EGF） were widely studied but at various concentrations. This study aimed to optimize the concentrations of combined bFGF and EGF by evaluating their effects on proliferation and collagen secretion of fibroblasts. Methods： Fibroblasts were differentiated from rat adipose mesenchymal stem cells （ADSCs）. Flow cytometry and immunohistochemistry were used for cell identification. The growth factors were applied at concentrations of 0, 1, 10, and 100 ng/ml as three groups：（1） bFGF alone, （2） EGF alone, and （3） bFGF mixed with EGF. Cell proliferation was evaluated by Cell Counting Kit-8 assays. Expression of Type I and III collagen （Col-I and Col-1II） mRNAs was evaluated by real-time quantitative reverse transcription-polymerase chain reaction. Statistical analysis was performed with SPSS software and GraphPad Prism using one-way analysis of variance and multiple t-test. Results： ADSCs were successfully isolated from rat adipose tissue as identified by expression of typical surface markers CD29, CD44, CD90, and CD45 in flow cytometry. Fibroblasts induced from ADSC, compared with ADSCs, were with higher mRNA expression levels of Col I and Col III （F = 1.29, P = 0.0390）. bFGF, EGF, and the mixture ofbFGF with EGF can enhanced fibroblasts proliferation, and the concentration of 10 ng/ml of the mixture ofbFGF with EGF displayed most effectively （all P 〈 0.05）. The expression levels of Col-I and Col-Ill mRNAs in fibroblasts displayed significant increases in the 10 ng/ml bFGF combined with EGF group （all P 〈 0.05）. Conclusions： The optimal concentration of both bFGF and EGF to promote cell proliferation and collagen expression in fibroblasts was 10 ng/ml at which fibroblasts grew faster and secreted more Type I and III collagens into the extracellular matrix, which might contribute to the stabilit

关键词： Adipose Mesenchymal Stem Cells Basic Fibroblast Growth Factor Epidermal Growth Factor Fibroblasts Tissue Engineering

Intracoronary pressure gradient measurement in acute myocardial infarction patients with the no-reflow phenomenon during primary percutaneous coronary intervention

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Chinese Medical Journal 2020年第7期133卷 766-772页

作者： Ming-Dong Gao En-Yuan Zhang Yuan-Ying liu xiao-wei li Jian-Yong xiao Gen-Yi Sun Yin liu Department of Coronary Care Unit Tianjin Chest HospitalTianjin 300222China

Background:Various experimental and clinical studies have reported on coronary microcirculatory dysfunction("no-reflow"phenomenon).Nevertheless,pathogenesis and effective treatment are yet to be fully *** study aimed to measure the intracoronary pressure gradient in the no-reflow artery during emergent percutaneous coronary intervention and explore the potential mechanism of ***:From September 1st,2018 to June 30th,2019,intracoronary pressure in acute myocardial infarction patient was continuously measured by aspiration catheter from distal to proximal segment in the Department of Coronary Care Unit,Tianjin Chest Hospital,respectively in no-reflow arteries(no-reflow group)and arteries with thrombolysis in myocardial infarction-3 flow(control group).At least 12 cardiac cycles were consecutively recorded when the catheter was pulled *** forward systolic pressure gradient was calculated as proximal systolic pressure minus distal systolic *** between groups was made using the Student t test,Mann-Whitney U-test or Chi-square test,as ***:Intracoronary pressure in 33 no-reflow group and 26 in control group were *** intracoronary forward systolic pressure gradient was-1.3(-4.8,0.7)and 3.8(0.8,8.8)mmHg in no-reflow group and control group(Z=-3.989,Plic pressure gradient was-1.0(-3.2,0)and 4.6(0,16.5)mmHg in respective groups(Z=-3.851,Plic pressure gradient and Z=-3.530,Plic pressure gradient).Conclusions:No reflow during emergent coronary revascularization is significantly associated with local hemodynamic abnormalities in the coronary *** nicorandil administration at the distal segment of a coronary artery with an aspiration catheter could improve the microcir

关键词： Acute myocardial infarction Coronary hemodynamics Intracoronary pressure gradient No-reflow Primary percutaneous coronary intervention

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng Song Ihar Razanau Juanxiu xiao wei xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

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界面掀起和轴力对组合梁动力弯曲特性的影响

振动与冲击 2016年第8期35卷 124-131,137页

作者：杨骁李晓伟汪德江上海大学土木工程系上海200072

考虑组合梁界面的法向/切向部分相互作用以及各子梁轴力的二阶效应,利用Hamilton原理得到了位移描述的Euler-Bernoulli组合梁非线性动力弯曲及一阶近似的初边值问题,并应用微分求积法研究了考虑界面法向/切向部分相互作用组合梁的临界... 详细信息

考虑组合梁界面的法向/切向部分相互作用以及各子梁轴力的二阶效应,利用Hamilton原理得到了位移描述的Euler-Bernoulli组合梁非线性动力弯曲及一阶近似的初边值问题,并应用微分求积法研究了考虑界面法向/切向部分相互作用组合梁的临界荷载和固有频率。在通过与已有解析解和有限元结果对比验证本文微分求积法正确性和适用性的基础上,进行了参数分析,研究了组合梁界面刚度对组合梁动力特性和稳定性的影响以及轴力对组合梁固有频率的影响。数值结果表明:组合梁的固有频率与临界荷载随界面刚度的增加而增加,并逐步趋于完全作用组合梁的固有频率与临界荷载;当轴向压力逐渐增加并趋于临界载荷时,组合梁的一阶固有频率逐渐减小并趋于零,并且临界载荷随法向和切向刚度的增加而增加。

关键词：组合梁稳定性与动力特性界面滑移和掀起二阶效应微分求积法

Effect of aeration on fast gas pressure tests

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Mining Science and Technology 2009年第6期19卷 756-760页

作者： CHEN Yu-jia JIANG Cheng-lin li xiao-wei TANG Jun WANG Chen YANG Fei-long WANG Fa-kai ZHANG Chao-jie DENG Shu-hua School of Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Given the problem of the long time required for testing gas pressure, we propose a fast-test method in which we used a technique of fast borehole sealing and air replenishing. Based on the characteristics of gas emission from boreholes to be tested, we built a theoretical model for calculating parameters during the process of increasing natural pressure and aeration. Using this model, we investigated the effect of different aeration conditions on velocity of pressure tests. The result shows that: 1) aerating air into boreholes can speed up gas pressure tests and 2) the more similar the pressure of the aerated air to the original gas pressure, the smaller the gas volume absorbed by coal and the shorter the time needed in pressure test. A case study in the Lu’an mining area shows that the time needed for gas pressure test is only 4 h using our method of aeration and 29 h under conditions of increasing natural pressure, saving time by 86.2%. This case study also indicates that, by using the aeration method, only one hour is needed for gas pressure to reach a stable state, which breaks the record of the shortest time needed for gas pressure tests in China.

关键词： aeration gas pressure fast test aeration pressure adsorption quantity

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垂直分层空时码的迭代检测算法

华南理工大学学报（自然科学版） 2006年第6期34卷 17-20页

作者：李小玮韦岗陈芳炯华南理工大学电子与信息学院广东广州510640

为解决垂直分层空时码的最优最大似然(ML)检测难以实现,而常用检测算法的性能受到错误传播影响的问题,提出了一种垂直分层空时码的迭代检测(ID)算法.该算法利用多天线接收信号的软信息进行迭代并行消除干扰,有效地降低了错误传播的影响... 详细信息

为解决垂直分层空时码的最优最大似然(ML)检测难以实现,而常用检测算法的性能受到错误传播影响的问题,提出了一种垂直分层空时码的迭代检测(ID)算法.该算法利用多天线接收信号的软信息进行迭代并行消除干扰,有效地降低了错误传播的影响.仿真结果表明,ID算法的收敛速度快,其检测性能比常用的ZF-DFE算法有明显的提高;在低信噪比区域,ID算法的检测性能与ML算法相当.

关键词：多输入多输出系统垂直分层空时码迭代检测软信息