远距离通讯

Aimed at the technology difficulty of intelligent inspect-alarm system on multi-point temperature detecting for the large storeroom for the remote distance,large roomage,high precision,based on the technology of PC and Microcontroller communication and scene-bus,the remote communication between PC and 8098 Microcontroller with current ring is introduced.The design method and realization technology of communication signals matching and software are introduced.

针对某大型飞机洞库温度智能检测报警系统研制中需要解决的距离远、空间大、精度要求高等技术难点，基于PC机与8098单片机通讯及现场总线技术，利用电流环实现了PC机与8098单片机之间的远程通讯，介绍了多机通讯信号匹配及软件设计方法和实现技术。

The thesis based on Yellow River Diversion Project. Through the research of the existing design of the supervising system of Yellow River Diversion Project, this passage pointed out some problems hard to be dealt with as follows:(1) Owing to the dispersion of control points and remote transfers of data, it cost a lot to construct the network of the supervising system and it was hard to implement the construction.(2) The connection mode of network needed to be taken into acount. Once the configuration of network changed or the nodes increased, the supervising system needed to be reconfigured.(3) Owing to the tanglesome physical communication line, the man-made communication error happened frequently.(4) When the communication malfunction occured, it needed various engineers to check and repair the fault.(5) It cost a lot to operate and maintain the supervising system.

本文以世界银行援建项目&Yellow River Diversion Project&(引黄入晋工程，编号：0015-K81062)为背景，在对引黄入晋工程的远程监控系统进行研究分析的过程中，指出了该系统在目前采用的有线光纤和有线电缆通讯技术下难以处理的一些问题：(1)由于监控点分散且传输距离较远，有线光纤和有线电缆的网络建设成本很高，实施困难；(2)需要考虑节点之间的连接形式，一旦网络结构发生变化或节点需要扩充，监控系统便需要调整，耗费大量的人力物力；(3)由于系统庞大，通讯的物理线路较为繁乱，在建设和维护阶段容易出现人为触碰等引起的通讯故障；(4)在出现通讯故障时，需要多方人员配合进行故障检测，不仅耗费人力和物力，且不利于故障排除；(5)运行和维护成本较高，需要很多运行维护人员进行大量繁杂的工作。

It can increase the automatic degree to sedimentation test as well as improve its test accuracy by on-line error compensation. And have the ability of field-bus communication and data storage, so the information can be communicated for long-distance or stored for long-term. With the SIMATIC S200 series PLC as a core and mated with the field-bus communication module and related components, I bring forward a complete design of hardware, and design some related procedure of the PLC and monitor computer.

本文将介绍一种基于数字信号处理和现场总线技术的新型高速公路沉降仪，不仅提高了沉降测试的自动化程度，而且通过在线误差补偿手段提高了测试精度，并且具备现场总线通讯和强大的数据存储能力，可实现信号的远距离传输或长期存储。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。