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1.
CO_2激光照射对大鼠免疫功能的影响富光华陈桂英(天津市职工医学院300071)(天津武警医学院)关键词CO_2激光,免疫功能EffectsofCO_2LaserIrradiationonImmuneFunctioninRats¥FuGuanghua;?..  相似文献   

2.
智能化脉冲和连续CO_2激光治疗系统曲世浦,吴磊,郑庭康,贾锋,范静逸,关奕奕(上海激光技术研究所200233)关键词超脉冲,智能化,CO_2激光IntellectualizedPulseandCWCO_2LaserTreatmentInstrume?..  相似文献   

3.
林波  赵仪 《光电子.激光》1995,6(5):267-269
氧气氛中高温超导Y_1B_(a2)C_(u3)O_X靶的激光等离子体光谱强度研究林波,赵仪,孙爱民,张树东,袁相津(西北师范大学物理系)StudyofSpectroscopicIntensityoftheLaser-InducedPlasmaofY-Ba...  相似文献   

4.
CO_2和CO激光激活介质用作相位共轭反射镜的非线性元件引言产生“长”脉冲(10~103μs)辐射的脉冲和脉冲一周期CO2激光器及co激光器可用于各种目的(例如材料加工、光泵等)。为了改善此类激光辐射角的方向性,可在非线性介质中产生四波相互作用应用辐...  相似文献   

5.
可调谐TEACO_2激光在AgGaSe_2晶体中的多波长倍频获成功中国科学院安微光机所承担的国家自然科学基金项目“可调谐TEACO2激光在AgGase2中的倍频研究”,经有关科研人员的共同努力,取得了突破性进展,在国内首次成功的实现了光棍选颁TEACO...  相似文献   

6.
李淑华  吕艳华 《激光杂志》1994,15(5):234-235
CO_2激光在肛肠科的应用李淑华,吕艳华,柴平,黄红(山东省潍坊市人民医院激光室)我院自1989年以来,应用CO_2激光治疗320例肛肠科疾患。其中包括外痔,血检性外痔、肛裂。这三种疾病都是临床上常见病,多发病。用CO_2激光聚焦法一次性治疗,经随访...  相似文献   

7.
CO_2激光治疗腱鞘囊肿2例山东省高密县痔瘘医院禚柏欣治疗方法:采用CO2激光输出功率30W,光斑直径0.2~0.3mm。常规皮肤消毒后,以2%利多卡因局部浸润麻醉,用CO2激光点射汽化囊肿中心,形成直径0.2~0.25cm小孔,深达囊腔,挤压排空腔?..  相似文献   

8.
CO_2激光照射对大鼠血浆血栓素和前列环素的影响傅征(南开大学生物化学及分子生物学系)富光华(天津卫生职工医院)徐东琴(天津中医学院病理教研室)PlasmaTxB_2and6-keto-PGF_(1α)ContentChangesinRatsTreat?..  相似文献   

9.
研究了CO2激光和He-Ne激光对酿酒酵母菌SaccharomycescerevisiaeAS2.1189的生理刺激作用和诱变效应;就两种激光不同的辐照剂量、酵母菌细胞的消长及其乙醇代谢的变化进行了比较。  相似文献   

10.
采用激光作热源合成了Al_2O_3-WO_3,Cr_2O_3-WO_3,Sb_2O_3-WO_3,CdO-WO_3,Fe_2O_3-WO_3等系列陶瓷材料。测量这些材料的阻温特性,结果表明这些材料都是负温度系数热敏电阻材料。讨论激光合成陶瓷工艺过程中所表现出来的特殊生长形态,这些形态与激光在合成材料中形成的温场分布、材料的导热特性、材料对激光的吸收等有关。通过理论计算得出的温场分布与实验结果很好符合。论述用激光作热源合成陶瓷与传统工艺相比所具有的独特优点,指出该工艺目前尚未解决的问题及今后的研究方向。  相似文献   

11.
Three alternative schemes for secure Virtual Private Network (VPN) deployment over the Universal Mobile Telecommunication System (UMTS) are proposed and analyzed. The proposed schemes enable a mobile node to voluntarily establish an IPsec-based secure channel to a private network. The alternative schemes differ in the location where the IPsec functionality is placed within the UMTS network architecture (mobile node, access network, and UMTS network border), depending on the employed security model, and whether data in transit are ever in clear-text, or available to be tapped by outsiders. The provided levels of privacy in the deployed VPN schemes, as well as the employed authentication models are examined. An analysis in terms of cost, complexity, and performance overhead that each method imposes to the underlying network architecture, as well as to the mobile devices is presented. The level of system reliability and scalability in granting security services is presented. The VPN management, usability, and trusted relations, as well as their behavior when a mobile user moves are analyzed. The use of special applications that require access to encapsulated data traffic is explored. Finally, an overall comparison of the proposed schemes from the security and operation point of view summarizes their relative performance. Christos Xenakis received his B.Sc. degree in computer science in 1993 and his M.Sc. degree in telecommunication and computer networks in 1996, both from the Department of Informatics and Telecommunications, University of Athens, Greece. In 2004 he received his Ph.D. from the University of Athens (Department of Informatics and Telecommunications). From 1998–2000 was with the Greek telecoms system development firm Teletel S.A., where was involved in the design and development of advanced telecommunications subsystems for ISDN, ATM, GSM, and GPRS. Since 1996 he has been a member of the Communication Networks Laboratory of the University of Athens. He has participated in numerous projects realized in the context of EU Programs (ACTS, ESPRIT, IST). His research interests are in the field of mobile/wireless networks, security and distributed network management. He is the author of over 15 papers in the above areas. Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Greece, in 1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and 1984, respectively. From 1983 to 1986, he was on the faculty of Electrical Engineering and Computer Science at the University of Connecticut, Storrs. From 1986 to 1994 he was on the faculty of the Electrical and Computer Engineering Department at Northeastern University, Boston, MA. During the period 1993–1994 he served as Director of the Communications and Digital Processing Research Center at Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks Laboratory (UoA-CNL) and the Networks Operations and Management Center. His research interests are in the design and performance analysis of broadband networks, and wireless/mobile communication systems and services. He has authored more than 150 papers in the above areas. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in the framework of the Advanced Communication Technologies & Services (ACTS) and Information Society Technologies (IST) programmes funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE). He is chairman of the board of the Greek Universities Network, the Greek Schools Network, and member of the board of the Greek Research Network. In 1994, he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications.  相似文献   

12.
随着企业规模逐渐扩大,远程用户、分支机构、合作伙伴也在不断增多,关键业务的需求增加,出现了一种通过公共网络(如Internet)来建立自己的专用网络的技术,这种技术就是虚拟专用网(简称VPN)。本文首先介绍了VPN的概念,对VPN的实现技术进行了分类和适用性分析,然后分析了各种类型的企业在信息安全方面的需求和限制,根据不同企业的特点提出了不同的VPN解决方案,最后,对VPN在集成电路企业中的应用做了简单的拓朴展示。  相似文献   

13.
Thanks to their structure, the SOI technologies present several intrinsic advantages for analog and RF applications. Indeed, as it is well established now, these technologies allow the reduction of the power consumption at a given operating frequency. Moreover, the high-insulating properties of SOI substrates, in particular when high resistivity substrate is used, make that these technologies are perfect candidates for mixed-signal applications. In the present paper, we will discuss the performances of the SOI technologies in radio-frequency range. First of all, the high-frequency behavior of SOI substrates, thanks to the characterization of transmission lines, will be shown. The impact of the SOI substrate resistivity on the performances of passive components will also be analyzed. Then, an overview of RF performances of SOI MOSFETs for two different architectures, fully- and partially-depleted, will be achieved and compared to the bulk ones. Finally, the influence of some specific parasitic effects, such as the kink effect, the self-heating effect and the kink-related excess noise, on the RF performances of SOI devices will be studied, thanks to a specific high-frequency characterization.  相似文献   

14.
徐春霞 《电子工程师》2004,30(5):65-67,73
在讨论了接入控制器(AC)网络管理系统安全重要性的基础上,分析了SNMP协议的应用,包括对其3个版本SNMPv1、SNMPv2及SNMPv3的优缺点的对比,并解释了该设备网络管理系统采用SNMPv3版本的原因.详细介绍了AC所实现的管理信息库的内容,包括RFC1213协议、IEEE 802.1x协议、RMON协议、Web DHCP、EAP_OTP、EAP_MD5、EAP_TLS、EAP_SIM等多种认证协议以及网络管理系统的五大功能.最后阐述了AC安全网络管理系统结构的设计与实现.  相似文献   

15.
自动测试系统中的总线技术   总被引:3,自引:2,他引:1  
自动测试系统满足现代科研生产中对测试高速度和高精度的要求,其发展方向是标准化、模块化和系列化,而标准的总线技术是满足这三化的关键技术,总线技术作为自动测试系统的核心,其发展推动了自动测试系统的更新换代.按照自动测试系统中出现的总线技术的顺序,依次对GPIB,VXI,PXI,LXI的基本特性、优缺点及应用进行概括,重点是结合在实际中组建自动测试系统对总线的选型,从宏观上比较了选取传统的卡式仪器总线或基于以太网的新型总线的因素.从而使用户在选取总线时更有针对性和目的性.  相似文献   

16.
雷达探鸟技术发展与应用综述   总被引:3,自引:0,他引:3  
探鸟雷达已成为机场鸟击防范、风力发电场鸟击风险评估、鸟类自然保护区鸟情观测与科学研究的重要工具。文中首先论述了探鸟雷达的主要组成部分。然后,分析了地面杂波、空域杂波和其他无关目标对探鸟雷达探测效果的影响,进而介绍了传统的杂波抑制方法和相参雷达杂波抑制技术,以及先进的探鸟雷达采用的目标检测、目标跟踪、目标显示、数据记录和雷达组网等数据处理技术。接着,给出了当前的探鸟雷达能够获取的目标轨迹、回波大小、回波强度、信号波动、飞行速度、飞行高度等反映飞鸟目标特性的主要指标。最后,描述了国内外四种典型雷达探鸟系统,并针对雷达探鸟技术的未来发展提出了一些思考及可行性建议。  相似文献   

17.
事件科普营销模式探究   总被引:1,自引:0,他引:1  
王勇  王蒲生 《科普研究》2013,8(2):26-30
从事件的视角看科普,已形成了社会公共事件、社会热点事件、社会突发事件等社会事件中嵌入科普的应急科普模式。但从科普的视角看事件,应急科普模式只是依托事件展开科普的组成部分,结合事件营销和科普营销的已有研究基础,本文提出事件科普营销模式,界定其依借公益性、聚焦性和危机性事件的内涵和依附性、新闻性、策划性三个特征,并从科学技术渗透疆常生活、资源整合、投入产出效率等角度论述其兴起的内在依据,并提出借势方式和造势方式下的四种路径。  相似文献   

18.
机器人系统通常用于人工介入成本过高、危险过大或者效率过低的任务。近年来,随着人工智能、自动驾驶、物联网等众多相关学科的全面发展,机器人在很多行业的应用也越来越广泛、成熟;与民众生活密切相关的物流机器人的配送应用也在逐步发展;互联网下,电商的充分发展为物流机器人的配送应用提供了明确的应用场景。而在抗击新型冠状病毒肺炎疫情时期,区域人群需要实行严格隔离,隔断病毒人传人的感染途径。针对这样的状况,物流机器人可发挥其巨大优势,为民众提供物资配送服务,可有效隔断病毒人际传播,避免人员配送过程中可能带来的病毒扩散风险,针对性地解决疫情隔离阶段物资供给最后一里的难题。  相似文献   

19.
为提高天馈问题被发现的准确性和维护效率,提出了基于高斯分布的最佳方向角解决方案来诊断运营商天馈覆盖问题。首先计算 UE 上报的具有定位信息的每个 MR 采样点与基站之间的位置方向信息,然后按照位置方向的一定角度间隔逐个统计各区间的MR采样点占比,取MR采样点占比最大的角度区间为该扇区的、基于用户热点分布的最佳天线方向角,最后将该最佳方向角与后台天线基础数据库中基站方向角进行比对,发现天馈系统接反、天线覆盖方向不合理、后台天线数据库错误等一系列天馈相关问题。经验证,采用该算法发现天馈问题的成本、准确率和效率较现有方法有明显改善?。  相似文献   

20.
建设应急专网是为了满足重特大灾害事故救援、应急处突、重大活动保障等统一指挥调度通信的需要,是维护社会公共安全的重要通信手段。随着无线电技术的快速发展,传统的窄带应急通信技术体制难以满足新形势下多媒体数据通信、互联互通、安全抗干扰等需求,数字化、宽带化、泛在化成为应急专网发展的必然趋势。首先,概述了应急专网通信的技术体制及发展趋势,介绍了全球应急专网通信研究框架,重点分析了美国、欧洲、亚太等国家和地区应急专网频谱规划及使用现状,最后结合我国应急专网频谱规划情况,从技术趋势、产业发展、频段选择、建设模式等方面提出了我国应急专网建设的建议。  相似文献   

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