用AVICap窗口类实现双目视频的捕获

讨论了利用微软提供的VFW(video for Windows)的AVICap窗口类进行视频捕获的基本方法，并结合作者开发的软件给出了在Windows环境下用VC 编程实现的双目视频捕获程序的关键源代码。     

用VC++5.0实现视频捕获编程

在桌面视频会议、可视电话等多媒体应用中,获得数字视频是一个关键的前提。在Video for Windows(VFW )出现之前,捕获数字视频是一项极其复杂的工作。Microsoft的Visual C++自从4.0版就开始支持Video forWindows(简称VFW),这给视频捕获编程带来了很大的方便。关于多媒体应用开发,市面流行资料中介绍较多的是MCI(媒体控制接口),而本文着重介绍的是如何使用Visual C++提供的AVICap窗口类进行视频捕获以及其中涉及到的概念和关键问题。     

Delphi中的数据集过滤和数据库连接

Borland公司的Delphi是当前最为方便的Windows程序设计工具之一。Delphi对访问数据库提供了强有力的支持，许多人以Delphi作为数据库开发工具。利用Delphi不仅可以极快地开发出高效的Windows程序，还可以开发出功能强大的数据库应用程序。     

Borland Delphi开发快速入门

一、简介及与VB 3.0 Pro版的比较 Delphi 1.0是Borland International于1995年2月发布的可视化开发工具,一经推出便引起了产业界的极大关注。美国五家最著名的PC杂志在1995年组织的Windows可视化应用程序开发系统评比中,Delphi 1.0一举击败竞争对手,荣登榜首。 在国内,Delphi作为Client/Server开发工具已经开始得到重视。与VB等开发工具相似,Delphi更广范的用途在于进行Windows下应用程序的快速开发(Rapid ApplicatonDevelopment),而不仅仅是像PowerBuilder和SQLWindows的C/S这样的开发环境。下面就对Delphi与流行的Visual Basic 3.0 Pro版作一个比较:     

Windows平台中视频采集卡应用程序的开发

介绍了如何在Windows平台中使用Delphi开发有关视频采集卡的应用程序,并给出了示例。由于使用的是Windows系统内置函数和消息,所以对于其它开发语言如VB,VC等同样适用。     

Delphi中新元件的创建与使用

元件(Component)是Delphi的核心,有了它用户能很轻松地开发出功能强大的Delphi应用程序。本文意在通过一个简单的例子向读者介绍如何创建并使用自己设计的元件。 一般来说,开发自己设计的元件要经过以下几步:元件设计、元件创建、为元件编写代码、在项目中使用此新元件(本文程序在Delphi3.0、4.0中通过)。     

基于Jabber的远程双向视频诊断技术研究

专家通过远程双向视频系统诊断农作物病虫害，是一种新兴且有效的病虫害防治方法。深入研究了Jabber和H．264编码技术，首先通过VFW技术捕获农作物病虫害的视频，H．264编码技术对视频进行压缩，压缩后的视频数据通过Jabber服务器进行传输，对端通过H．264解码播放农作物病虫害视频，从而实现远程诊断。客户端采用Delphi作为开发工具，服务器端采用Jabber2．0实现了设计。     

Delphi通过ADO技术访问数据库方法研究

Delphi是一种功能强大的编程语言,可以编写任何类型的程序。在众多的软件中,在数据库方面,Delphi表现出色,可以开发多种数据库结构的客户服务器模式数据库应用程序。文中研究了数据库程序开发中的最基本的一步,即如何用ADO连接数据库的方法。通过实例演示,展示了这种方法的细节,具有可操作性和可重复性,可供其他程序员借鉴,提高开发效率。     

基于Delphi的多线程同步方法的设计与实现

多线程程序具有广泛的应用前景,特别是在网络应用程序中,可以提高带宽利用率和程序反应速度.为了达到下载大型网站的目的,在编写离线浏览软件的过程中,需要下载大量的Web文件.其中一个技术要点就是多线程下载问题.为了解决这一难题,分析了进程的原理和机制,研究了Windows系统下多线程程序的设计方法,提出了在Delphi中实现多线程同步的新方法,提供了程序的设计框架,解决了一些技术难题,并在大型网站文件系统的下载软件中进行了试验与运用,为基于Delphi的多线程程序提供了具有普遍意义的设计思路.     

基于Web的动态环境下视频兴趣区的自动捕获系统设计

传统视频捕获系统无法解决动态环境下视频区的图像大幅度波动问题,捕获的视频兴趣区误差较高。因此,设计基于Web的动态环境下视频兴趣区的自动捕获系统,该系统中的视频读取模块从Web摄像头获取基带视频并进行解密工作,解密后的基带视频被存储为VGA格式的动态环境视频,随后将其传输到自动捕获模块。自动捕获模块对动态环境视频进行编程控制和实时存储操作,并为用户计算机提供设备接口,以实现用户对动态环境下视频兴趣区的自动捕获。系统后台Web服务端对自动捕获模块获取的视频信息进行自主交互,完成视频信息的存储、处理和系统资源的管理。软件给出了动态环境下视频兴趣区的自动捕获目标函数,以及动态环境视频的读取语言。实验结果表明,所设计的系统拥有捕获误差低的优点。     

Development of the readout system for waveguide multilayer optical card

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.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

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.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

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.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

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.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.