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On the Detection of Multiple-Access Spatial Modulations

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Chinese Journal of Electronics 2017年第1期26卷 172-178页

作者： zhou enzhi HAO Li Key Lab of Information Coding and Transmission Southwest Jiaotong University

The detection problem for the Multipleaccess Spatial modulations(M-SM) is investigated in this paper, where multiple transmitters adopting spatial modulation communicate to the receiver at the same *** optimal Maximum-likelihood(ML) detection suffers from the high computational complexity, while Sphere decoding(SD) can not reduce the complexity effectively because of the multiple active antennas in M-SM. In order to avoid the high complexity, a Space-alternating generalized expectation-maximization(SAGE) algorithm aided List-pro jection(S-LP) detector is proposed and applied to M-SM systems. The received signal vector is firstly projected onto the subspaces spanned by the columns of channel matrices corresponding to the possible active antennas. Then some combinations of antenna indices with the largest pro jections are selected as candidate index sets,based on which, a modified SAGE algorithm is applied to update the candidate symbols. Both analysis and simulation results show that the proposed S-LP detector achieves a near-optimum performance with a significantly reduced complexity compared with ML and SD detection.

关键词： Multiple-input multiple-output(MIMO) Spatial modulation(SM) Multi-user detection

Optimization of pore structure and wet tribological properties of paper-based friction materials using chemical foaming technology

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Friction 2022年第9期10卷 1317-1334页

作者： Chang LI Jie FEI enzhi zhou Rui LU Xiaohang CAI Yewei FU Hejun LI State Key Laboratory of Solidification Processing Shaanxi Province Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi’an 710072China

Paper-based friction materials are porous materials that exhibit anisotropy;they exhibit random pore sizes and quantities during their preparation,thereby rendering the control of their pore structure *** with different pore structures are obtained by introducing chemical foaming technology during their preparation to regulate their pore structure and investigate the effect of pore structure on the properties of paper-based friction *** results indicate that the skeleton density,total pore area,average pore diameter,and porosity of the materials increase after chemical foaming treatment,showing a more open pore *** addition of an organic chemical foaming agent improves the curing degree of the matrix ***,the thermal stability of the materials improves significantly,and the hardness and elastic modulus of the matrix increase by 73.7%and 49.4%,*** dynamic friction coefficient increases and the wear rate is reduced considerably after optimizing the pore *** wear rate,in particular,decreases by 47.7%from 2.83×10^(−8) to 1.48×10^(−8)cm^(3)/J as the foaming agent content *** importantly,this study provides an effective method to regulate the pore structure of wet friction materials,which is conducive to achieving the desired tribological properties.

关键词： paper-based friction materials chemical foaming technology pore structure tribological properties

Frequency and risk factors of psychological distress among individuals with epilepsy before and during the outbreak of the SARS-CoV-2 Omicron variant in China:an online questionnaire survey

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Acta Epileptologica 2024年第1期7卷 36-43页

作者： Xiaoting Hao Qi Zhang Chenxi Zhong enzhi Li Yingqi Jiang Jiajun Xu Yuanyuan Li Dong zhou Bo Yan Department of Neurology West China HospitalSichuan University No37 Guoxue AlleyChengduSichuan Province610000China Department of Psychiatry and Mental Health West China HospitalSichuan University/West China School of Clinical MedicineSichuan UniversityChengdu610000China Department of Neurology Chengdu Shangjin Nanfu HospitalChengdu611730China West China School of Nursing Sichuan University Chengdu610000China Department of Clinical Research Management West China HospitalSichuan UniversityChengdu610000China

Background The COVID-19 pandemic substantially increases the risk of severe psychological distress among people with epilepsy(PWE),especially those with monthly household income12 should consult a psychiatrist,especially during major *** study was aimed to compare the frequency of psychological distress among Chinese PWE before and during the outbreak of the SARS-CoV-2 Omicron variant,and to identify risk factors for such *** In this prospective study,we collected sociodemographic data of PWE aged>14 years,who were treated at our center during December 1 to 15,*** participants completed the 6-item Kessler Psychological Distress Scale before the outbreak and again during the *** visitors who were unrelated to those patients during the outbreak were included as a *** logistic regression analysis was performed to identify risk factors of severe psychological distress and its *** Of the 223 PWE,127 were tested positive for SARS-CoV-2,while 174 of 218 controls were positive for *** neurological symptoms were similar between PWE and controls with *** average Kessler score of PWE was significantly higher during the outbreak than before it(9.93±3.98 vs.8.52±0.23,P<0.001).The average score of controls during the outbreak(5.146±0.35,P<0.001)was significantly lower than that of the *** identified three independent predictors for severe psychological distress in PWE during the outbreak,i.e.,monthly household income<5000 RMB(OR=0.252,95%CI 0.064–0.998,P=0.048),severe psychological distress before the outbreak(OR=0.067,95%CI 0.026–0.174,P<0.001),and seizure onset within 30 days before the assessment during the outbreak(OR=0.356,95%CI 0.157–0.805,P=0.013).Of the three predictors,the last one was also an independent predictor for exacerbation of psychological distress during the outbreak(OR=0.302,95%CI 0.123–0.741,P

关键词： Epilepsy Neurological symptoms Psychological distress COVID-19 pandemic

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思想政治教育内容寻源中国传统文化的合理性

科教导刊 2017年第12X期 87-88页

作者：周恩智张鸿韬北方民族大学宁夏银川750021 周口师范学院河南周口466001

从理论的严谨性和系统性要求的角度来说,对思想政治教育内容寻源中国传统文化的合理性进行充分解析,是基本的前期逻辑梳理;尝试从增强思想政治教育实效性的角度剖析其内容选择的传统文化指向,是一种完全必要的研究和探讨。中国传统文化... 详细信息

从理论的严谨性和系统性要求的角度来说,对思想政治教育内容寻源中国传统文化的合理性进行充分解析,是基本的前期逻辑梳理;尝试从增强思想政治教育实效性的角度剖析其内容选择的传统文化指向,是一种完全必要的研究和探讨。中国传统文化中积极的内容建构起一座精神财富的宝库,其优秀的品质与人们对价值和意义的执着追求相契合,就更加能够引起共鸣、获得认可;道德的全人类性、先在的主体认同基因、中国传统文化的"根基"地位以及"文化自信"对思想政治教育的影响也是思想政治教育内容寻源中国传统文化具有合理性的有力支撑。

关键词：思想政治教育内容中国传统文化合理性

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肌电假肢手抓握力控制系统的设计与实现

传感器与微系统 2020年第9期39卷 94-96,100页

作者：周恩至张翼邓华中南大学高性能复杂制造国家重点实验室湖南长沙410083

为使上肢残疾者佩戴的肌电假肢手能够稳定地抓握物体,设计了一种基于表面肌电(sEMG)信号和力敏电阻器(FSR)的假肢手抓握力控制系统。系统以数字信号处理器(DSP)-ARM双处理器作为控制核心,通过sEMG传感器采集上肢残疾者手臂的表面肌电信... 详细信息

为使上肢残疾者佩戴的肌电假肢手能够稳定地抓握物体,设计了一种基于表面肌电(sEMG)信号和力敏电阻器(FSR)的假肢手抓握力控制系统。系统以数字信号处理器(DSP)-ARM双处理器作为控制核心,通过sEMG传感器采集上肢残疾者手臂的表面肌电信号,从中解码期望的抓握力;通过FSR传感器采集假肢手抓握物体时的实际抓握力,作为反馈信号;然后运用无模型自适应控制方法实现假肢手抓握力的闭环控制。抓握力控制实验表明:该系统能够控制假肢手以期望力稳定地抓握物体。

关键词：表面肌电(sEMG)信号力敏电阻假肢手抓握力控制力解码无模型自适应控制

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辽宁爪鲵种群的空间遗传结构

野生动物学报 2024年第1期45卷 110-117页

作者：李振鑫贺晨刘恩志周瑜杨宝田董丙君沈阳师范大学生命科学学院沈阳110034

利用13个微卫星位点对4个地理种群的辽宁爪鲵(Onychodactylus zhaoermii)进行遗传多样性及空间遗传结构研究,结果表明:230个样本中共检测到69个等位基因,各种群的差异等位基因数(Na)为1.538~4.462,遗传多样性较低。除本溪县新开村种群(... 详细信息

利用13个微卫星位点对4个地理种群的辽宁爪鲵(Onychodactylus zhaoermii)进行遗传多样性及空间遗传结构研究,结果表明:230个样本中共检测到69个等位基因,各种群的差异等位基因数(Na)为1.538~4.462,遗传多样性较低。除本溪县新开村种群(PopⅣ)外,岫岩县华山村(PopⅠ)种群、辽阳县鸡爪村(PopⅡ)种群、辽阳县韩家村(PopⅢ)种群间无显著遗传分化,遗传变异主要来源于种群内部。在以水系划分种群时,表现出一定的遗传差异。在采样位点直线距离小于500 m时,辽宁爪鲵个体间具有较高的遗传相似性。4个种群之间存在3个屏障,结合地理因素,PopⅣ与其他3个种群之间形成了显著的地理阻隔,建议将各地理种群确立为一个管理单元,加强栖息地保护,减少生境片段化对辽宁爪鲵野生资源的影响。

关键词：辽宁爪鲵微卫星遗传多样性空间遗传结构

Finite element simulation on the deep drawing of titanium thin-walled surface part

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Rare Metals 2010年第1期29卷 108-113页

作者： GAO enzhi, LI Hongwei, KOU Hongchao, CHANG Hui, LI Jinshan, and zhou Lian State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The deep drawing of titanium thin-walled surface part was simulated based on a self-developed three-dimensional finite element model. After an investigation on forming rules, a virtual orthogonal experimental design was adopted to determine the significance of processing parameters, such as die radius, blank holder force, and friction coefficient, on the forming process. The distributions of thickness and equivalent plastic strain of the drawn part were evaluated. The results show that die radius has a relative major influence on the deep drawing process, followed by friction coefficient and blank holder force.

关键词： deep drawing titanium alloy finite element simulation orthogonal experiment processing parameters

Disease awareness and dietary habits of patients with epilepsy in western China:a cross-sectional study

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Acta Epileptologica 2021年第1期3卷 220-225页

作者： Qi Zhang Wenjing Li enzhi Li Xiao Yang Nanya Hao Bo Yan Dong zhou Xiaoting Hao Department of Neurology West China HospitalSichuan UniversityChengdu 610000Sichuan ProvinceChina Department of Clinical Research Management West China HospitalSichuan UniversityChengdu 610000China West China School of Nursing Sichuan UniversityChengdu 610000China Outpatient Department West China HospitalSichuan UniversityChengdu 610000China

Background:The optimal management of epilepsy includes engaging patients through education on knowledge of the disease,its treatment and diet ***:This was a cross-sectional survey-based cohort study,aimed to investigate the awareness of epilepsy in Chinese patients and to understand their dietary *** were consecutively enrolled from epileptic patients treated in a single epilepsy center from October 1,2019 to February 29,2020.A self-reported questionnaire(Cronbach’sα=0.758)consisting of 3 parts was sent to 407 patients with *** questionnaire included items on demographic information,epilepsy features,awareness of epilepsy treatment and dietary ***:About half of the patients(53.8%,219/407)thought epilepsy was curable and only 80%knew that the first choice of treatment is *** 58.6%of the patients with low educational level preferred the use of antiepileptic drugs(p=0.014),52.7%believed that the medication should not be stopped immediately after seizure control(p=0.026),especially after surgery(40.5%,p=0.011).Patients with lower household monthly incomes had less awareness of the use of antiepileptic drugs than patients with higher incomes:only 39.2 and 49.8%of patients with lower incomes thought that the drugs could be stopped after epilepsy surgery or seizure control,respectively,compared to 51.6 and 66.1%with higher ***(86.2%),caffeine(56.8%)and strong tea(49.1%)were top three foods considered by the patients to be avoided to prevent *** 30.2%of patients identified at least one food that made them susceptible to ***:Patient education on epilepsy,antiepileptic drugs and diet for management of seizures should be provided especially to patients with less education,lower income or inaccurate beliefs of epilepsy in Western China.

关键词： Epilepsy Awareness Antiepileptic drug Dietary habit Epilepsy education Survey

Fracture distribution in overburden strata induced by underground mining

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Deep Underground Science and Engineering 2022年第1期1卷 58-64页

作者： Wenli Yao enzhi Wang Xiaoli Liu Ran zhou Department of Hydraulic Engineering State Key Laboratory of Hydroscience and EngineeringTsinghua UniversityBeijingChina Department of Hydraulic Engineering YSD Rail Transit Construction Company LimitedGuangzhouChina

Coal-mining activities give rise to a series of ecological environmental problems,such as ground settlement and groundwater *** fact,they are mainly caused by mining-induced ***,it is necessary to study the mining-induced fracture distribution to identify the behavior of rock mass ***,the fractures in overburden strata cannot be directly measured owing to the special ***,the majority of previous studies are based on experiments or *** this reason,this study first used a discrete element method to simulate the shape of mining-induced fractures in overburden ***,a geophysical tool of transient electromagnetic method(TEM)was used to investigate the mining-induced fracture *** on the low-resistivity anomaly area,the water-rich area in overburden strata was analyzed to be mainly caused by fracture *** the mutual authentication between numerical simulation and TEM results,the mining-induced fractures in overburden strata were *** study can enhance the understanding of mining-induced fracture distribution on the one hand and guarantee the coal mining safety on the other,thus guiding the coordinated development between coal mining and environmental protection.

关键词： groundwater seepage mining-induced fracture numerical simulation rock mass deformation TEM