It is very difficult to realize digital rf , but we can realize digital if . digital if mainly include : digital up convert ( duc ^ digital down convert ( ddc ) , a / tk d / a and number control oscillator ( nco ) 目前实现射频数字化还有一定的困难，但可以实现中频部分数字化。数字中频处理主要包括数字上变频、数字下变频、 a d与d a的处理以及数控振荡器等。
The control system is a ddc system , which is the important part of the hulin heat _ supply control system . the hardware adopted in the system include industrial pc , signal input devices and signal output devices 该系统是虎林市集中供热监控系统的重要组成部分，是一个集中式数字直接控制系统。系统中采用的硬件主要有：工业控制计算机，信号采集设备和信号输出设备。
Also by return e - mail , we will appreciate sending us your proforma invoice cif new york included all charges ( ddc , baf , etc ) , and your sales contract , for our first trial order for the following models , for our study and confirmation 同时,请贵方用电子邮件传送贵方的形式发票,价格以cif纽约,包所有费用(包括ddc baf等)为基础,以及贵方的销售合同,型号请看以下试单,此供我方研究和确认
At the same time , as the chief agent of yamatake corporation of japan in the north and east of china , we provide all yamatake ' s ba products , including bms , ddc , sensors , control valves , butterfly valves , actuators and etc 同时我公司为日本山武公司华北区的系统首席代理商，向用户提供山武公司全套楼宇自控产品，包括系统控制软件、 ddc控制器、传感器、电动调节阀、蝶阀及风阀执行器等。
We use fieldbus technique controlling the boiler ' s running , instead of ddc and dcs controlling system . considering most boilers in our country were still using the normal analogy instrument and the whole digit intelligence appliance were not popularity 现场总线技术要求现场的设备传送数字信号，需要使用智能仪表，但当前我国大部分锅炉还是采用常规模拟仪表，全数字化智能仪表还未普及。
An system of cataloguing and retrieval of information is employed based on international classification standard - dewey decimal classification ( ddc ) and cataloguing rule - anglo - american cataloguing rules 2nd ed . ( aacr2 ) 资源中心内的馆藏资料是根据国际标准的杜威分类法deweydecimalclassification ( ddc )分类及按英美编目规则anglo - americancataloguingrules2nded . ( aacr2 )编目。
A direct digital control ( ddc ) system was adopted , which can grab the dynamic image of fruits in real time , and send the results of image processing to the parallel port of computer , then control several step motors " status at the same time 本研究采用计算机直接数字控制方式，对动态水果图像进行实时采集，并通过计算机的打印端口输出图像处理结果，实现同时对多个执行器的动作状态进行控制。
Also by return e - mail , we will appreciate sending us your proforma invoice cif new york included all charges ( ddc , baf , etc ) , and your sales contract , for our first trial order for the following models , for our study and confirmation 您若能通过邮件的方式发给我们关于纽约到岸价的销货清单(其中包含有的费用如ddc , baf等,以及您的销售合同以供我们首次订单,之后的模块产品研究及确认所需,我们仍将不胜感激
The paper begins with a profound analysis of software radio theory if digital receiver technique , pci bus system . brings forward an if digitalization receiver architecture , introduce the power and clock , adc , ddc , control part cpld , process part fpga , data buffer part in detail , gives the simulation of fpga and cpld . then introduces the pcb design , and process si simulation , gives the conclusion at the end 本文首先介绍了软件无线电以及中频数字化接收机的相关理论,其次,介绍了该中频数字化接收机的实现方案,详细说明本接收机中电源和时钟、 ad转换、数字下变频、控制芯片cpld 、处理芯片fpga 、数据缓冲等各模块的设计,给出fpga和cpld的仿真结果,然后,介绍了印刷电路板( pcb )设计,初步对pcb进行信号完整性分析( si )仿真,最后给出结论。
Based on the quick development of computer network , this thesis deals with how to apply network technology to civil and architectural engineering . the finished research contains as follows : the research on reraote - network - monitor - system , the realization of the data collection of ddc ( direct digital controller , multi - loop data circuit monitor ) , the communication , the real time control of remote network . moreover , the remote - network - monitor - system is applied in the engineering practice in which monitoring the security of high framed girder and plank 其中包括：研究了远程网络检测系统基本结构，实现了下位机(多路数据巡回检测仪)现场数据采集、下位机与上位机通信、远程网络实时控制采集过程等；成功编制了下位机与上位机通信软件和用于动态更新、存储数据的数据库系统；将远程网络检测系统应用于工程实例，完成了高层建筑框支梁安全性监测、不抽芯板专利技术检测。
