调幅技术远比调频技术及数位广播技术简单,而且,广播也是现代社会不可缺少的一部分。所以，本文使用MATLAB软件下的Simulink对调幅广播进行建模与仿真。首先，介绍该课题研究的背景、目的、意义以及工作内容等。然后，在简要介绍MATLAB及Simulink的建模环境与仿真环境的基础上，通过对AM信号的调制与解调，对调幅广播系统系进行了仿真和分析，得出具体的仿真模型，并对仿真波形进行分析说明。最后，给出结论并提出好的改进方法。针对搭建的广播系统信噪比增益非常小，为了提高发射效率，采用另外一种幅度调制方式
Modulation technology is far more than the FM technology and digital broadcasting technology is simple.Moreover, the broadcast is an indispensable part of modern society.So,This paper use MATLAB software Simulink for the modeling and simulation of am radio.First of all, introduce the background, purpose, significance and content of the research.The brief introduction of the MATLAB and Simulink modeling environmentwith the simulation environment, on the basis of through the AM broadcast signal modulation and demodulation the AM broadcast system is the simulation and analysis, gives a detailed simulation model and simulation waveforms are analyzed.Finally (2017-03-22, matlab, 1089KB, 下载5次)
生公寓管理软件，是以高校的管理方式为实例而设计的一种实用型管理系统。本系统最大的特点是通用性、简单操作性，适用于同行业以及一些同类型的企业管理。随着学校寄宿人员的增多，公寓管理人员的负担越来越重，为了让所有公寓管理人员能从繁重的工作中解脱出来，实现无纸化办公；使工作更有条理，更方便，更有效率而开发出这套公寓管理软件。
软件从对学生的分房开始到最后的公寓管理全部电脑化。它主要包括：公寓、寝室的配置、住宿人员登记、卫生检查、公寓资产、学生违纪、值班老师记录以及对学生住宿情况查询，可以更快地了解到每个学生的住宿情况,使公寓的管理效率更高，做的更好！
Health and apartment management software, is a practical management system designed by colleges and universities for instance. The biggest feature of this system is versatile, simple operability, applicable to the same industry as well as some of the same type of enterprise management. With the increase of the boarding school staff, apartment managers increasingly heavy burden on all apartment managers freed from the heavy work to achieve the paperless office to make the work more organized, more convenient, more efficiency and the development of this apartment management software.
Software from the students of the housing distribution to the end of the apartment management is all computerized. It mainly includes: apartments, bedroom configuration, the registration of accommodation officers, health checks, apartment assets, student discipline, teacher on duty records and the student accommodation, you can quickly understand each student s accommodation, apartment management more effi (2012-02-19, Visual C++, 650KB, 下载3次)
首先，论文在分析了电缆故障种类及原因的基础上论证了研究电缆故障监测数据采
集与传输系统的必要性。紧接着又详细的阐述了虚拟检测技术的发展，更进一步证明了
基于 Lab VIEW 的电缆故障监测数据采集与传输系统设计的可行性，并且研究了故障信
息的小波分析及其在虚拟仪器中的实现，将小波变换引入到数据分析中，为更好的识别
故障信号提供了理论支持，并通过仿真验证了理论的可行性。
First, the paper analyzed the types and causes of cable failure on the basis of demonstrated research cable fault monitoring data collection and transmission system necessary. Then it was explained in detail the development of virtual testing technology, further proof of the cable fault Lab VIEW-based monitoring data collection and transmission system design, feasibility, and studied the fault information of the wavelet analysis and its implementation in the virtual instrument , the wavelet transform into the data analysis, to better identify the fault signal provides a theoretical support and simulation to verify the theoretical feasibility. (2011-11-08, LabView, 1764KB, 下载45次)
摘 要:定时恢复是数字接收机中的关键技术,基于某特定LEO低轨卫星通信系统应用,重点研究了异步时钟采
样恢复法的工作原理,提出了一种改进的Gardner定时误差检测算法,给出了整个定时环路的具体实现方案,并针对其
性能进行了分析。仿真结果表明,在大多普勒加速度的卫星信道环境下,该方案能够满足系统设计的要求,且实现结
构简单、优化,可大幅降低算法复杂度,在较高信噪比的情况下,具有更加优化的性能。
Abstract: The timing recovery is a key technology in the digital receiver, based on a particular application of LEO LEO satellite communication system, focus on the asynchronous sampling clock recovery method works, a modified Gardner timing error detection algorithm, given a concrete realization of the regular loop programs, and analyzed for its performance. Simulation results show that the acceleration of the satellite channels in large Doppler environment, the program can meet the requirements of system design and realization of simple structure, optimization, can significantly reduce the complexity of the algorithm, in the case of high SNR, with more optimized performance. (2010-12-31, Others, 398KB, 下载15次)
单工无线呼叫系统分发射和接收两大部分。发射部分采用锁相环式频率合成器技术， MC145152和MC12022芯片组成锁相环，将载波频率精确锁定在35MHz，输出载波的稳定度达到4×10-5，准确度达到3×10-5，由变容二极管V149和集成压控振荡器芯片MC1648实现对载波的调频调制；末级功放选用三极管2SC1970，使其工作在丙类放大状态，提高了放大器的效率，输出功率达到设计要求。接收部分以超大规模AM/FM立体声收音集成芯片CXA1238S为主体，灵敏度、镜像抑制、信噪比等各项性能指标均达到设计要求；音频功率放大器采用集成芯片LM386，电压放大倍数最大为200。采用PT2262/2272编码/解码电路实现了数据传输业务以及对台号的选择等功能；音频输入和数据输入可自动转换；AT89S52作为整个系统的控制部分，程序设计采用C语言在KEIL51的编译器上编程实现；显示采用128×64点阵型液晶显示。经测试，整机功能齐全，各项性能指标符合系统要求，接收波形稳定，无明显失真。
The simplex wireless-calling system consists of two parts: transmit part and receive part.The transmit part adopts the phase-locked loop pattern of frequency synthesizing technology and uses the MC145152 and MC12022 chips to compose the phase-locked loop.It locks the frequency of the carrier-wave at 35MHz.The stabilization of the carrier-wave can be 4×10-5,the accuracy can be 3×10-5.The frequency modulation and the confection of the carrier-wave are realized by the capacity-changing diode V149 and the integration voltage-control oscillator MC1648 chip.The end power amplifier uses the audion 2SC1970 to make it work in the third magnifying state,it improves the efficiency of the magnifier and the power of the output reaches the design demand.The receive part uses the super cosmically AM/FM dimensional sound stereo radio reception integration chip CXA1238S as the main part.The sensitivity、the mirror-control restrain、the SNR and every capability index all reach the design demand.The audio (2009-08-30, Others, 612KB, 下载156次)
搞过数据库系统的人都知道， 数据库系统中大量的基本功能无非是数据表的CRUD
增删改查和批量分页查询，Jdon框架结合对象设计和J2EE/JEE 设计理念将这个看似简
单功能开发过程抽象出来，放在框架中，并且随着应用程序一起运行，提供优化性能提
升等。
日常企业信息化过程中，经常会一些表单数据输入数据库，使用 Jdon 框架可以在
一两个小时内完成这样的应用，当你只需要快速建立一个软件应用系统，Jdon 框架正
好适合你，而且拥有灵活的拓展性和方便的维护性。
如果你希望马上手一个 Hello World的案例，可直接到“开发一个简单Jdon应用系
统”章节。
Been engaged in a database system knows that the database system, the basic functions of a large number of data tables is nothing more than CRUD
Additions and deletions to search and batch query page, Jdon object framework combining design and design concept J2EE/JEE this seemingly simple
Single-function development process from the abstract, on the framework, and together with the applications running, to provide optimal performance
Upgraded.
Day-to-day process of enterprise information, often some form of data entered into the database, using the framework can Jdon
12 hours to complete such an application, when you only need to quickly create a software application systems, Jdon framework is
Good for you, and have a flexible and easy to expand the maintenance.
If you wish to immediately hand the case of a Hello World directly to "develop a simple application of the Department of Jdon
EC "section. (2009-06-17, Java, 1877KB, 下载6次)
摘要:分析了影响同步电动机矢m:控制电流控制环动态特性的主要因索.指出同步电动机反电动势是
其中最重要的{一扰因索针对通常采用的F I(比例一积分)电流调 y器因下作频带的限制无法在较高转速时
抑制反电动势的影响.提出了前馈补偿和变电流环增益的设计方法.少}应用于基于数-f_信写处理器的矢m:控
制系统给出了系统结构及软硬件设计方案实验结果表明.该系统硬件简的一控制精l夏高.动态}h I能良好（.caj)
Abstract: This paper analyzes the impact of synchronous motor vector m: control of current control loop dynamic characteristics of the main due to demand. Pointed out that the synchronous motor counter electromotive force is one of the most important result of (1 nuisance claim against the usual method of FI (the proportion of points 1) current transfer y browser due to restrictions under the band can not be at a higher speed when the inhibitory effects of counter electromotive force. proposed feedforward compensation and variable gain current loop design method.) used on a number of less-f_ vector processor to write the letter m: control system gives the system architecture and hardware design The experimental results show. The system control hardware simple one fine summer of high-l.) h I can be dynamic sound (. caj) (2008-04-15, TEXT, 41KB, 下载6次)
JoyOA在业内首次提出“快乐办公”的概念，并具备业内领先的四大技术：
1、大文件上传技术
一般情况下通过Web方式上传文件，因技术的限制，只能上传下于4M甚至2M的文件，美特易通过自主研发的大文件上传组件，彻底打破这一局限，能够上传高大1000M的文件。
2、多角色管理技术
一个用户可同时具备多个权限，通过角色切换可以轻松完成不同部门的工作或管理任务。
3、指纹认证技术
为安全性有严格要求的企业或单位提供指纹识别登录系统，让你的系统像银行保险箱一样安全。
4、Web情报分析技术
监控竞争对手的产品、收集您感兴趣的财经信息、分析各大网络媒体上的热点消息，我们为您提供了强大的情报分析系统。
JoyOA 历经锤炼，吸取同类产品之精华，快乐办公，从JoyOA开始……
JoyOA the first in the industry "Happy office" concept, and with the four industry-leading technology : one, file uploads technology under normal circumstances through Web upload documents, due to technical limitations, only under upload 2M to 4M or even the document meete through our own research and development of large file uploads components, a complete breakdown of this limitation, tall 1000M able to upload the document. Two more of a technical management role users may also have a number of powers, through role-switching can ease the efforts of various departments, or administrative tasks. 3, fingerprint authentication technology for the strict safety requirements of the business or agency to provide fingerprint identification system log, let your system as safe as bank saf (2006-04-15, C++, 2823KB, 下载30次)
太原理工大学硕 士 学 位 论 文 摘 要 随着Internet/Intranet 建设的飞速发展,Web 服务作为当 前Internet 上最热门的一种服务,得到了广泛的应用。Web 技术 发展到今天,人们已经可以把数据库技术引入到Web 系统中。将 Web 与数据库结合起来,不仅把Web 与数据库的所有优点集中在 一起,而且充分利用了大量已有的数据库信息资源,可以使用户 在Web 浏览器上方便地检索和浏览数据库的内容,Web 数据库技 术为传统的信息系统应用模式转轨到新的应用模式提供了具体 解决方案,也为解决信息孤岛问题提供了思路。
Taiyuan University of Technology with a master's degree thesis Abstract Internet/Intranet construction of the rapid development of Web services as the current most popular on the Internet as a service, a wide range of applications. Web technology into today, people can turn the technology into the database to the Web system. Web and Database will combine not only the Web and database together all the advantages, but also made full use of the existing large database of information resources, allowing customers to the Web browser to facilitate the retrieval and browsing the contents of the database, Web database technology to the traditional information system applications model transition to the new model of application specific solutions, but also to address the issue of isolated isl (2005-04-14, MultiPlatform, 110KB, 下载48次)