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1.
非晶硅太阳能电池的新进展   总被引:1,自引:0,他引:1  
对非晶硅材料的物理性能及工艺优势进行了阐述,其中介绍了一种新型的刻划成图工艺,即等离子CVM,简单回顾了非晶硅太阳池的历史发展,分析了非晶硅太阳电池当前所存在的问题,提出了其发展的方向,其中,主要论述了叠层非晶硅太阳电池,并介绍了几种新型的非晶硅电池,最后,概括了非晶硅太阳电池的应用现状及前景。  相似文献   

2.
本叙述了Internet来自外部,内部,硬件,软件方面的十种安全威胁和攻击,给出了防火墙的限制,隔离,筛选,过滤和屏蔽作用,介绍了防火墙的六种基本结构类型,论滤了过滤路由器,双宿主主机,主机过滤,过滤子网和吊带式五种安全结构,分析了传统防火墙的七种不足,给出了目前防火墙混合应用包过滤技术,代理服务技术和其他一些技术的发展趋势。  相似文献   

3.
Wedding……     
兄弟结婚了,朋友结婚了,朋友的朋友结婚了;男的结婚了,女的结婚了,不男不女的也结婚了;有感情的结婚了,没感情的结婚了,认识不认识的结婚已经无所谓了……  相似文献   

4.
    
《印制电路资讯》2007,(4):79-79
马,本来自由自在的在山间撒野,渴了喝点山泉,累了就睡在地上晒太阳,无忧无虑。可是自从有了伯乐,马的命运就改变了,给它的头戴上笼辔,在它的背上置放鞍具,栓着它,马的死亡率已经是十之二三了,然后再逼着它运输东西,强迫它日行千里,在它的脚上钉上铁掌,马的死亡率就过半了。  相似文献   

5.
频道多了,节目也要跟上吴为忠文年岁渐长,早已过了不惑之年,到了这样的年龄,晚上如果没有公务缠身就懒得外出,看电视似乎成了我业余生活的一个主要内容。但是,电视看得多了,总忍不住要说三道四,这也许是一种职业病。我的住处已经装上了闭路电视,又与有线电视台联...  相似文献   

6.
本文简述了无线寻呼机制造技术的最新发展,详细介绍了寻呼机在小型化,增加信息存储,提高抗干扰能力,增加新功能方面采用的新技术,新方法,强调了模糊技术,纠错技术对提高寻呼机抗干扰能力的作用,最后,展望了寻呼机制造技术的发展趋势。  相似文献   

7.
移动通信网络优化服务由于借助了设备厂商和专业第三方优化服务公司的技术优势,很好地提升了现有网络运行的质量,弥补了网络运营商技术人员的缺口,培养了运行维护人员的专业技能,积极发挥了现有网络资源的利用率,有效地降低了网络的维护成本,提高了客户的满意度和运营效益,  相似文献   

8.
重庆市“教学与集邮”活动已走过10年的历程。10年来,存重庆邮政、邮协及各级教委的支持下,重庆市各中小学对“教学与集邮”展开了广泛深入的研究,组织了集邮活动,举办了集邮讲座,推出了一批“教学与集邮”校本教材,取得了累累硕槊。集邮进校园、进课堂,使集邮活动在校园扎根,大大丰富了校园文化内容,引发了广大青少年对集邮这项健康、文明活动的兴趣,拓宽了学生的综合宴践能力,陶冶了学生的高尚情操,提高了学生思想素质和文化艺术素养,培育了集邮队伍的生力军。  相似文献   

9.
《数码》2005,(8):116-116
现在数码单反相机的价格已经越来越低了,甚至还出现了5000元左右的产品。当然,相机有了,除了镜头之外,剩下的最重要的东西就是存储卡了,对于那些喜欢疯狂拍片的摄友来讲,这款4GB的高速CF卡成了他们的最佳选择,有了它,你再也不用担心使用数码伴侣会意外丢失数据了。而且从何种上来讲,也会方便100倍!  相似文献   

10.
介绍了安徽电视台开放式演播室的整体布局,逐一分析了电源,灯光,视频,音频,通话,指示,时钟和传输系统,其中重点介绍了视频和音频系统。  相似文献   

11.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

12.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

13.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

14.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

15.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

16.
Waveguide multilayer optical card (WMOC) is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling & processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic (VB) language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.  相似文献   

17.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

18.
The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.  相似文献   

19.
Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.  相似文献   

20.
An insert layer structure organic electroluminescent device(OLED) based on a new luminescent material (Zn(salen)) is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn(salen)/Liq/LiF/A1/CuPc/NPD/Zn(salen)/Liq/LiF/A1. Effective insert electrode layers comprising LiF(1nm)/Al(5 nm) are used as a single semitransparent mirror, and bilayer cathode LiF(1 nm)/A1(100 nm) is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.  相似文献   

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