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MIMO Hardware simulator Using standard Channel Models and Measurement Data at 2,2 and 3,5 GHz

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通讯和计算机（中英文版） 2013年第4期10卷 525-544页

作者： Bachir Habib Gheorghe Zaharia Hanna Farhat gha'fs.el Zein Institute of electronics and Telecommunications of Rennes IETR UMR CNRS 6164 Rennes 35708 France

High Prevalence of Musculos.eletal Disorders and self-Medication among street Vendors in Bangui, Central African Republic (CAR)

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Occupational Diseases and Environmental Medicine 2023年第4期11卷 199-212页

作者： H.D. Mossoro-Kpinde Perrin Ariel Kongbanda Augustin Balekouzou Henri saint Calvaire Diemer Julienne Anaïs Paola Demba yabada Chloé Naïgha Liliane Dengue Nzobe Gerard Grésenguet Mor Ndiaye Direction de la Médecine du Travail Ministère du Travail de l’Emploi de la Protection Sociale et de la Formation Professionnelle Bangui Central African Republic Département de santé Publique Faculté des Sciences de la Santé Université de Bangui Bangui Central African Republic Faculté des sciences de la santé Université de Bangui Bangui Central African Republic Comité National de Lutte contre le sIDA Bangui Central African Republic service de Médecine du Travail et de Médecine Légale Faculté de Médecine de Pharmacie et d’Odontologie Université Cheick Anta Diop Dakar Senegal

Introduction: Musculos.eletal disorders (MsDs) are a set of peri-articular conditions that result mainly in pain and functional discomfort. They represent a major occupational health problem in all areas of activity. The objective of this work was to determine the prevalence of MsDs among street vendors in the city of Bangui in the Central African Republic (CAR). Methods: A cross-sectional study was conducted from september 01 to October 31, 2021 in Bangui, the capital of CAR. The study population consisted of street vendors which were included at the entrance of 4 large markets of Bangui after giving informed consent. The sample size, calculated according to the schwartz formula, was 384. sociodemographic data (age, gender, level of education, marital status), professional data (the duration of sale in hours, the distance traveled per day);and health data (the health problems suffered by itinerant sellers and the means of dealing with them) were collected using a pre-established self-questionnaire. This collected data was processed using Microsoft Excel 2013 and Epi-Info version 7 software. Results: Among 384 street vendors included, women represented a quarter (24.9%). The average age was 27 years;the 25-34 age group was the most represented (50%). About two-thirds (64.8%) sold for at least 12 hours and traveled more than 10 km (69.3%) per day. The main health problems reported by street vendors were musculos.eletal disorders (95.8%). Their locations concerned the upper limbs shoulder 65.36% (251), elbow 24.22% (93). Non-ergonomic postures that stress the back and joints all day long, causing pain are risk factors for MsDs. These MsDs were treated by self-medication with non-steroidal anti-inflammatory drugs (22.0%), mainly sold on the street. Conclusion: MsDs dominated the health problems of street vendors. These problems raise the need for recognition and support for these workers to optimize their performance while preserving their health through awareness and

关键词： street Vendors Musculos.eletal Disorders Ergonomy self-Medication Central African Republic

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鹅头型汊道个体差异研究

四川大学学报（工程科学版） 2015年第2期47卷 8-14页

作者：刘亚李义天武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072 长江科学院水利部江湖治理与防洪重点实验室湖北武汉430010

鹅头分汊河道具有极度弯曲的平面外形与主支汊周期性移位交替的演变特性,在长江中下游广泛分布,但汊道之间平面形态及河势演变特征存在明显差异。以长江中下游鹅头分汊型河道演变分析为基础,从江心洲(滩)个数、汊道弯曲程度,河势演变周... 详细信息

鹅头分汊河道具有极度弯曲的平面外形与主支汊周期性移位交替的演变特性,在长江中下游广泛分布,但汊道之间平面形态及河势演变特征存在明显差异。以长江中下游鹅头分汊型河道演变分析为基础,从江心洲(滩)个数、汊道弯曲程度,河势演变周期长短、主支汊交替方式等方面总结了鹅头型分汊河道间的个体差异特征,并探讨了产生此差异的主要原因。结论表明,不同汊道进出口节点的走向及进口节点挑流作用的强弱是产生鹅头分汊型河道个体差异的主要原因:进出口节点转折角越大,鹅头型汊道越宽广;进口节点挑流作用越强,河势演变周期越短。

关键词：鹅头分汊河型河谷地貌个体差异

Grey Hole Attack Detection and Prevention Methods in Wireless sensor Networks

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Computer systems science & Engineering 2022年第7期42卷 373-386页

作者： Gowdham Chinnaraju s.Nithyanandam Department of Computer science and Engineering PRIST Deemed to be University613403India

Wireless sensor Networks(WsNs)gained wide attention in the past decade,thanks to its attractive features likeﬂexibility,monitoring capability,and *** overcomes the crucial problems experienced in network man-agement and facilitates the development of diverse network *** existence of dynamic and adaptive routing features facilitate the quick formation of such ***ﬂexible architecture also makes it highly vulnerable to dif-ferent sorts of attacks,for instance,Denial of service(Dos).Grey Hole Attack(gha)is the most crucial attack types since it creates a heavy impact upon the components of WsN and eventually degrades the performance of *** cur-rent study,a simple attack detection,prevention and reduction approach is *** is to secure the WsN from gha and other such attacks by warning and blocking the malicious suspensions and by examining the storage *** of blocking the entire host,the presented approach speciﬁcally elim-inates the malicious ***,in case of no malicious trafﬁc detection,the host gets *** current study,the researchers simulated the model under MATLAB environment and the outcomes showed an enhanced performance and increased utilization of Central Processing Unit(CPU)and packet delivery ratio.

关键词： Grey-Hole Attack WsN detection prevention reduction network performance

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长江中下游鹅头型汊道航道整治目标河型研究

水利学报 2015年第4期46卷 443-451页

作者：刘亚汪飞李义天武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072 长江科学院水利部江湖治理与防洪重点实验室湖北武汉430010 长江水利委员会水文局湖北武汉430010

鹅头分汊河型由于其汊道大幅平移及主支汊频繁交替,历来是碍航问题最为突出的河段,目前关于鹅头分汊河型的治理目标存在微弯分汊和微弯单一河型的争议。本文在总结鹅头分汊河型碍航特性的基础上,结合其滩槽格局成因,从分汊河道水流能量... 详细信息

鹅头分汊河型由于其汊道大幅平移及主支汊频繁交替,历来是碍航问题最为突出的河段,目前关于鹅头分汊河型的治理目标存在微弯分汊和微弯单一河型的争议。本文在总结鹅头分汊河型碍航特性的基础上,结合其滩槽格局成因,从分汊河道水流能量守恒原理出发,提出了鹅头分汊河道航道整治的目标河型:认为进口节点的挑流作用放大了水流的年内横向摆幅,使得边滩难以长期稳定;进出口节点的存在限制了汊道的延伸平移,因此保留分汊河型是适应这一特征的必然选择。同时保持两汊较大的阻力差异,削弱主支汊格局对进口水流条件的敏感性,将更有利于主航槽的稳定,即存在一定曲率差的分汊河型是鹅头型汊道航道整治的目标河型;具体河段的汊道曲率可根据进口水力特征及进出口河床高程差计算而得。

关键词：鹅头分汊河型河床演变航道整治

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鹅头分汊河型河道演变时空差异研究

应用基础与工程科学学报 2015年第4期23卷 705-714页

作者：刘亚李义天卢金友长江科学院水利部江湖治理与防洪重点实验室湖北武汉430010 武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

鹅头分汊河道为极度弯曲的分汊河型,具有河势周期性交替的演变共性,但其平面形态及河势变化特征因时因地而异.为探究长江中下游不同鹅头分汊型河道之间的空间性差异及同一汊道在不同周期演变中的时间性差异,本文从汊道弯曲程度、河势演... 详细信息

鹅头分汊河道为极度弯曲的分汊河型,具有河势周期性交替的演变共性,但其平面形态及河势变化特征因时因地而异.为探究长江中下游不同鹅头分汊型河道之间的空间性差异及同一汊道在不同周期演变中的时间性差异,本文从汊道弯曲程度、河势演变周期长短及滩槽冲淤变形幅度等方面总结了鹅头分汊型河道演变的时空差异性,并探讨了产生此差异的主要原因.研究表明,不同汊道进出口节点的走向及进口节点挑流作用的强弱是产生鹅头分汊型河道空间差异的主要原因;对于特定的鹅头型汊道,进口节点挑流作用在上游河势及年内径流过程的影响下发生强弱调整,这是造就其时间性差异的主要因素.

关键词：鹅头分汊河道河床演变时空差异

基于全球公顷和国家公顷的生态足迹核算差异分析

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中国人口·资源与环境 2007年第5期17卷 80-83页

作者：吴开亚王玲杰复旦大学公共管理与公共政策创新基地上海200433 厦门大学经济学院福建厦门361005

为对基于全球公顷或是国家公顷来核算生态足迹的差异进行比较分析,分别采用全球公顷法和国家公顷法对安徽省2003年生态足迹进行核算。全球公顷法核算的生态足迹需求、生态承载力、生态赤字分别为1.765 909 hm2/cap,0.435 083 hm2/cap,1.... 详细信息

为对基于全球公顷或是国家公顷来核算生态足迹的差异进行比较分析,分别采用全球公顷法和国家公顷法对安徽省2003年生态足迹进行核算。全球公顷法核算的生态足迹需求、生态承载力、生态赤字分别为1.765 909 hm2/cap,0.435 083 hm2/cap,1.330 826hm2/cap;而国家公顷法核算的结果则分别为0.955 026 hm2/cap,0.102 027 hm2/cap,0.852 999 hm2/cap。对核算结果差异的产生原因进行分析表明:①采用全球公顷法将会扩大国家生态足迹的核算误差;②全球平均产量难以体现产品之间的属性差异;③使用全球公顷法核算时的数据汇总难度大;④以国家为统计对象的全球公顷法在全球范畴内进行国际比较时具有优越性,但在对国家以下尺度进行生态超载分析时采用国家公顷法和国家平均产量更符合实际状况。

关键词：全球公顷国家公顷生态足迹核算安徽省

Carbon Footprint of Tourism sector in Portugal-Calculator Development

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Journal of Tourism and Hospitality Management 2021年第6期9卷 365-380页

作者： Marco Fernandes Pedro Neves Patrícia Araújo Isabel Brás.elisabete silva Polytechnic Institute of Viseu ViseuPortugal Biosphere Portugal ViseuPortugal

A carbon footprint(CF)calculator was developed to apply to a Portuguese touristic accommodation to contribute to a sustainable touristic *** some calculators are available online,they are related to the country reality or use outdated emission factors.A calculator based on national emission factors is *** calculator was developed in Microsoft Excel(version 365)and is based on the CO2e emissions resulting from electricity,water,fuels and food use,laundry and waste *** calculator development involved:study the accommodation emission sources,selection the environmental indicators,determination of the emission factors and development of the CF *** CF calculation was made considering the partial CF per component,a monthly and annual comparison of each indicator’s emissions contribution using *** emissions amount per overnight stay,per room,per area,were also assessed and these values were transformed into global hectare(gha).Avoided emissions calculation gives the information about the efforts in CF reduction,and two indicators were considered:electricity production from renewable energy sources and the amount of separated waste for *** was considered reforestation measures to achieve carbon *** calculator incorporates four components not often used:water,laundry,waste,food,and avoided emissions.

关键词： calculator carbon footprint greenhouse gases environmental indicators sustainable tourism

丰富环境对脑缺血大鼠突触界面结构修饰和PsD-95基因表达的影响

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心理学报 2008年第6期40卷 709-716页

作者：叶灵静徐晓虹王亚民张婧傅吉强钟浦峰朱艇浙江师范大学化学与生命科学学院金华321004

探讨丰富环境干预对局部脑缺血大鼠突触界面结构修饰和突触后致密物-95(postsynaptic density-95,PsD-95)mRNA表达的影响。栓塞健康雄性sprague-Dawley大鼠的右侧大脑中动脉,建立脑中动脉栓塞(mid-dle cerebral artery occlusion,MCAO)模型后,分为丰富环境缺血组(IE)、标准环境缺血组(Is),同时分别设丰富环境假手术组(sE)、标准环境假手术组(ss)。以Morris水迷宫检测大鼠的空间学习记忆能力,应用透射电镜、图像分析和细胞形态计量学技术,观察海马CA1区和额叶皮层突触界面结构变化,采用RT-PCR检测突触后脚手架蛋白PsD-95 mRNA的表达。结果表明:丰富环境干预能有效改善脑缺血导致的空间学习记忆能力下降,并对正常大鼠的空间学习记忆能力也有改善作用。同时,丰富环境干预能抑制局部脑缺血导致的突触数密度减少,该作用对额叶皮层特别明显;丰富环境干预不同程度地逆转脑缺血造成的突触界面参数变化,特别使突触间隙宽度显著减小、PsD厚度明显增加;并有效抑制因脑缺血诱导的PsD-95 mRNA表达下调。以上结果提示,丰富环境改善脑缺血大鼠的空间学习记忆能力可能与其促进缺血区边缘组织突触界面结构修饰,提高PsD-95 mRNA表达有关。

关键词：丰富环境短暂局部脑缺血突触界面结构 PsD-95 mRNA