基于Zig Bee技术的无线火灾报警系统构建,带原文的外文翻译

原文

Construction of Wireless Fire Alarm System Based on

ZigBee Technology

MA Shu-guang

Department of Fire Commanding, The Armed Police Academy, Langfang, 065000, China

Abstract

This paper points out the defect of wired automatic fire alarm system in used, and the necessity and possibility of constructing wireless fire alarm system. ZigBee technology based on IEEE802.15.4 and its characteristics are introduced. We also give out a method of constructing wireless fire alarm system based on ZigBee, including the design of construction, hardware and software.

? 2011 Published by Elsevier Ltd.

Keywords: ZigBee; wireless sensor; automatic fire alarm

1. Introduction

Most fire sensor networks are built based on CAN bus in currently used automatic fire alarm system, in which signals and data are transferred through cable. Compared to traditional distributed cable network, bus network have greatly improved in expansibility and difficulty of construction and maintenance. But there are still some defects. The cables are easily to be eroded, bitten by rats, frayed, causing to high fault rate and high false alarm rate. The cable transmission distance is limited, usually no more than 1km, otherwise the attenuation and interference will lead to failure of system.

We may conceive that, constructing automatic fire alarm system in wireless transmission way, can avoid above problems. A new way of wireless signal relay also can increase alarm signal transmission distance. With microelectronics and wireless communication technology development in recent years, this can become a reality. This paper introduces a method of constructing automatic fire alarm system based on ZigBee technology.

2. ZigBee Technology

ZigBee is an alternative name of IEEE 802.15.4, a wireless network protocol released in 2005. ZigBee technology is a two-way radio communication technology, mainly suitable for automatic control and remote controlbased on wireless communication. It can be embedded in various consuming electronics, family and building automation equipment, industrial control equipment, various sensors equipment, also supporting the geographical location function. ZigBee has the following features:

Low power dissipation. Due to short working cycle, it has low power dissipation in sending and receiving messages, and adopts a sleep mode. Two 5# dry batteries can support a node work for 6 to 24 months, or even longer.

Low cost. Dramatically simplifying the protocol and reducing the requirement of communication controller, causes very low cost. The modules are cheap, and ZigBee protocol patent is free.

Low transmission rate. It works at 250kbps rate, satisfying the application requirements of

low data transmission rate.

Short distance. The transmission distance between adjacent nodes is usually 10 ~ 100m. If increase transmitting power of RF, the distance can be 1-3km. If through the routing and communication relay, the distance will be even more.

Short time delay. ZigBee has optimization in time delay sensitive application, the communication delay and activated delay from dormancy is very short. Generally, from sleeping to working, just needs 15ms, and the nodes connecting to network needs only

30ms.

High capacity. ZigBee network can be constructed in different types. A master node can manage 254 nodes, still can extend to bigger network by each node. Total network can have 65535 nodes in theory.

High security. ZigBee provides a three-level safe mode, including data integrity checking and authenticating, using Access Control List (ACL) to prevent illegal data acquisition, using Advanced Encryption Standard (AES128) symmetrical passwords to determine the security attribute flexibly.

Free frequency band. It uses direct sequence spread spectrum technology, working at global free ISM 2.4GHz frequency band. Usually, application accord with the following conditions can consider using ZigBee technology:[2]

the equipment cost low, transmitting data volume is small

equipment is small in size, unfit to place big battery or power module

unfit to replace batteries frequently or inconvenience for charging repeatedly

cover a wide range of communication, many equipment in network , but only for monitoring and controlling Automatic fire alarm system has almost all of the above characteristics, so it’s very suitable to be built based on ZigBee technology.

3. System Designing

3.1. System Structure

Fig.1 System structure

The system uses ZigBee wireless network to achieve fire monitoring and automatic alarming, mainly includes three parts: the data acquisition nodes, data sink nodes and fire control center, [3] as shown in Fig. 1.

Data acquisition node is an embedded wireless sensor module integrating sensors, main control unit (MCU) and radio frequency (RF) communication functions. After preprocessing the

fire signals detected by the sensors, itchooses an optimal path to send them to the data sink node. The data sink nodes sends the data from the sensor network to the fire control center. When necessary, the data may also be sent to the fire control center by external network, such as Internet. Fire control center consists of supervision host and server. The server is used to store fire control data, electronic map, etc. The supervision host is used for data processing and statistical evaluation, displaying alarm information through peripheral equipment, and for data management, data query and interaction with the user.

3.2. System hardware

The system hardware mainly consists of data collector and data receiver. Data collector consists of sensors, MCU, RF chips, etc. MCU and RF chips are connected by PCI bus, they constitute the wireless transmission module. With the same kind of wireless module, data receiver communicates with the PC through RS232 asynchronous serial interface. In one direction, the control signals are emitted from the host to the data collector in wireless way, in another direction, the collected data is uploaded to the host. When fire signal is detected by the sensors, the fire control center will process and statistically evaluate the data, and convert it to suitable alarming indicator according with the pre-set rules, then send out alarm signals.

Diagram of the system hardware structure is shown in Fig. 2.

Fig.2 System hardware structure

MCU can choose 8 or 16-bit single-chip microcomputer with on-chip integrated ROM, such as MCS51 series, HCS08 series or MSP430 series MCU., Taking MC9S08GT60 for example, one type of HCS08 series, it works at 1.8V voltage, integrated 4KB RAM and 60KB Flash ROM, and integrated 8 channels 10-bit ADC, 2 SCI interface and 1 SPI interface. It also has corresponding internal clock module and background debug interface. [4] The MCU of the data collector receives the signal sent by the sensor, then sends it to RF chip after A/D conversion. While the MCU of the data receiver receives the data sent from the RF chip, and send it through RS232 interface to the up computer for further analysis. When necessary, it may also directly drive simple audible or visual alarm devices such as buzzer, LED, etc.

RF chip can choose ZigBee wireless transceiver series, CC series of TI or MC series of Freescale. They both work at 2.4 GHz band. Taking MC13192 for example, it is a low cost, low power consumption, high performance RF chip accord with ZigBee standard. It mainly consists of analysis receiving-transmission unit, digital modems, onchip frequency synthesizer, power manager and MCU interface. It’s working band is 2.405 ~ 2.480 GHz, data transfer rate is

250kbps, working frequency band can be divided into 16 channels, each channel bandwidth

5MHz. Due to the low transmission rate and the large bandwidth of the channel, so the SNR is very high, anti-jamming capability is strong.

External crystal provides the clock needed by MC13192, and the on-chip frequency synthesizer output signals provide the clock for MCU. Read-write operation on MC13192 is achieved through a standard four-wire SPI by the MCU. It should be pointed out that, most MCUs and RF chips produced by different companies can be collocated flexibly, but in practical engineering, it is suggested to use the products from same company in order to ensure the stability of the system. Also, embedded chips integrated MCU and RF chip can be adopted.

3.3. System software

System software includes three parts: wireless sensor node procedures, data sink node procedures and center monitoring procedures.

Wireless sensor nodes periodically detect environmental parameters. When the system begins to work, MCUs and RF chips are initialized firstly, then chooses the channel, opens interrupt for receiving data. Then initialize ADC and collect data to process. If there is an alarm signal, the signal, sensor node address and the collected data will be combined as alarm data, and translated into ZigBee communication protocol packets. Selecting an optimal communication path, the packets are sent to the data sink node, and waiting for the returned confirmation. Thus, a whole ZigBee wireless communication is completed. After receiving the confirmation returned from the sink node, the sensor node will stay at low power mode automatically. In addition, when the sensor node receiving a request from the sink node, it can collect data immediately, in order to realize real-time, active monitoring. The sensor node procedure is shown in Fig.3.

The sink node procedure is mainly to receive data from wireless sensor, confirming, then send it to the supervision host through RS232 interface.

Located in the fire control center, the supervision host is used for receiving the data sent by the sink nodes, monitoring , alarming, and controlling working condition of the sensor nodes. The monitoring procedure in upper computer is designed based on serial communication.

VC++ provides serial communication ActiveX can easily operate on serial port. Software sends request through serial port, indicating the data receiving process by a progress bar, and can display the data waveform through a display interface instantly, and save data to database for further analysis or inquiry at the same time.

Fig. 3 Flow chart of sensor node procedure

4. Conclusion

The wireless automatic fire alarm system constructed based on ZigBee overcomes the limitations of the cable alarm system and avoids high power consumption of the other wireless communications technology. Compared with existing wireless sensor network, it has some advantages such as low cost, high network capacity, long life. And system installation does less damage to buildings, conveniently to place nodes and maintenance. Avoiding the unsafe factors of fire, lightning strike in cable systems, it is suitable for various occasions, especially for fire control in museums, ancient building group , with a wide application prospect.

翻译

基于Zig Bee技术的无线火灾报警系统构建

MA Shu-guang

摘要

本文指出了有线火灾自动报警系统在应用中的缺陷，以及构建无线火灾报警系统的必要性和可能性。对基于IEEE802.15.4的Zig Bee技术及其特点进行了介绍。我们也给出了一个构建基于Zig Bee无线火灾报警系统的方法，包括结构设计，硬件和软件。

关键词：ZigBee;无线传感器；火灾自动报警

1。简介

大多数火灾传感器网络都建立在基于总线用于火灾自动报警系统，其中信号和数据通过电缆传输。与传统的有线网络相比，总线网络大大提高了可扩展性和施工难度和维修难度。但它仍有一些缺陷。该电缆是容易被腐蚀，被老鼠咬破，磨损，导致故障率高、误报率高。本电缆传输距离有限，传输距离通常不超过一公里，否则衰减和干扰会导致系统工作失败。我们可以设想，建设中的火灾自动报警系统的无线传输方式，可以避免以上问题。一种新无线信号继电器的传输方式的也可以增加报警信号传输距离。随着微电子技术和无线通信技术在最近几年的发展，这种新技术可以成为现实。本文介绍构建基于Zig Bee技术的自动报警火灾系统的方法。

2. ZigBee 技术

Zig Bee技术是IEEE 802.15.4另一个名称，一个发布于2005年的无线网络协议。Zig Bee 技术是一种基于无线通信的双向无线通信技术，主要适用于自动控制和远程控制。它可以被嵌入在各种消费电子，家庭和建筑中的自动化设备，工业控制设备，各种传感器设备，也支持地理位置函数。Zig Bee具有以下特点：

?低功耗。由于工作循环期短，它具有低功耗的发送和接收信息的特点，并可以采用一个睡眠模式。两个5#的干电池可以支持节点工作6到24个月，甚至更长。

?成本低。大大简化了协议和降低了通信控制的器要求，所以成本非常低。该模块很便宜，再者Zig Bee协议是免费的。

?低传输速率。它的速率为250kbps，满足应用要求，数据传输率低。

?短距离。相邻节点之间的传输距离通常为10米~100米。如果增加RF的传输功率，距离可以达到1-3km。如果通过路由和通信中继，距离会甚至会更长。

?延迟时间短。Zig Bee已优化延时灵敏的应用，通信延迟和从休眠激活延迟很短。一般来说，从睡眠到工作，只需要15毫秒，和节点连接到网络只需要30毫秒。

?高容量。Zig Bee网络可以构造不同类型。一个主节点可以管理254个节点，仍然可以扩展到更大的网络和每个节点。理论上在网络中总共有65535个节点。

?安全性高。Zig Bee提供三个层次的安全模式，包括数据完整性检查和认证，使用访问控制列表（ACL）防止非法数据采集，采用先进的加密标准（aes128）确定密码安全属性灵活。

?免费频段。它采用直接序列扩频技术，工作在全球自由频率带。通常，应用符合以下条件可以考虑使用Zig Bee技术：[ 2]

?设备成本低，传输数据量小

?设备尺寸小，不适合大电池或电源模块

?不宜经常更换电池或不便反复充电

?涵盖的沟通范围广泛，在所有网络中的设备的监测和控制系统中，但只有火灾自动报警系统几乎符合所有上述特征，所以它非常适合建造在Zig Bee技术的基础上。

3。系统设计

3.1。系统结构

Fig.1 System structure

该系统采用Zig Bee无线网络实现火灾监测和自动报警，主要包括三部分：数据采集节点，数据汇聚节点和消防控制中心，[ 3].如图1。

数据采集节点是一个嵌入式无线传感器模块的集成传感器，主控单元（单片机）和射频（射频）通信功能。经过预处理的火灾传感器探测到的信号，选择最优路径发送到数据汇聚节点。数据汇聚节点通过传感器网络发送数据到消防控制中心。必要时，数据也可能被发送到消防控制中心的外部网络，如因特网。消防控制中心由监控主机和服务器组成。服务器是用来存储控制数据，电子地图，等。监控主机进行数据处理和统计评价，通过外围设备显示报警信息，数据管理，数据查询和与用户的互动。

3.2。系统硬件

系统硬件主要由数据采集器和数据接收机组成。数据采集器由传感器，单片机，射频芯片组成，单片机和射频芯片等连接总线，它们构成了无线传输模块。有同类型的无线模块，数据通信接收器与计算机通过RS 232进行异步串行接口。在同一个方向，控制信号是通过无线的方式用电脑从主机发射到数据采集器，在另一个方向，收集的数据上传到主机。当火警信号由传感器检测，消防控制中心要处理和统计评价数据，并根据预先设定的规则将其转换为适当的报警指示，然后发出报警信号。

图2系统硬件结构如图2所示。

Fig.2 System hardware structure

单片机可选择8或16位单片机，具有片上集成功能，如MCS 51系列，MSP 430系列单片机的HCS 08系列，以mc9s08gt60为例。一个类型的HCS 08系列，他在1.8v的电压下工作，集成4kb RAM和60kb闪存存储器，集成8通道10位模数转换器，2个SCI界面和

1个SPI界面。它也有相应的内部时钟模块和后台调试接口。[ 4] 该数据采集器的单片机接收到传感器发出的信号，然后发送到射频芯片后转换。当数据接收器的单片机接收射频芯片发送的数据，并把它通过RS 232接口上计算机的进一步分析。必要时，也可以直接驱动简单声响或视觉报警装置如蜂鸣器，发光二极管，等。

射频芯片可以选择Zig Bee无线收发器系列，TI的CC系列或飞思卡尔的MC系列。他们两个都工作在2.4GHz频带。以mc13192为例，它是一种低成本，低功耗，高性能射频芯片，符合ZigBee标准。它主要包括分析收发单元，数字调制解调器，片上的频率合成器，电源管理器与单片机的接口。它工作在2.405~2.480 GHz，数据传输速率是250kbps，工作频段可分为16个通道，每个通道的带宽5兆赫。由于低传输速率和通道的频带宽，使信噪比很高，抗干扰能力强。

外部晶振时钟需mc13192提供，片内频率合成器输出信号为单片机提供时钟。在mc13192上的读写操作是通过一个标准的四线接口单片机实现。应该指出的是，不同的公司生产的大多数微控制器和射频芯片可以灵活配置，但在实际工程中，为保证系统的稳定性，还是建议使用同一公司生产的产品。此外，也可以采纳嵌入式芯片集成微控制器和射频芯片。

3.3。系统软件

系统软件包括三部分：无线传感器节点，数据汇聚节点和中心监控程序。[ 5]

无线传感器节点要定期的进行环境参数的检测。当系统开始工作，初始化单片机和射频的芯片，然后选择渠道，打开中断接收数据。然后初始化模数转换器数据采集开始进程。如果有一个报警信号，那这个报警信号，传感器节点的地址，收集到的数据将结合成一组报警数据，并翻译成Zig Bee通信协议数据包。选择一个最佳的通信路径，数据包被发送到数据汇聚节点，并等待确认返回。这样，一个完整的Zig Bee无线通信就完成了。在从节点收到确认后，传感器节点将自动停留在低功耗模式下。此外，当传感器节点从源节点接到一个请求，它可以收集数据，以实现实时主动的监控。传感器节点程序是显示在图3.

汇聚节点的程序主要是从无线传感器接收数据，确认信息，然后通过RS 232接口发送到监控主机。

安装在消防控制中心的主机，用于接收汇聚节点发送的数据，监测，报警，控制传感器节点的工作状态。上位机上的监控程序事基于多种通信协议设计的。VC++提供的ActiveX 系列串行通信能简单的在串行端口上实现操作。软件通过串口发送请求，通过进程指示数据接收的进展，并可以通过波形显示界面来显示数据，同时能将数据保存到数据库进一步分析或调查。

Fig. 3 Flow chart of sensor node procedure

4。结论

基于Zig Bee的无线火灾自动报警系统的构建克服了电缆报警系统和避免其他无线通信技术的高功率消耗的局限性。与现有的无线传感器网络相比，它具有低成本，高容量，长寿命。同时系统安装时不破坏建筑物安装节点和维护方便。避免发生火灾的不安全的因素，电缆系统中的闪电击，适用于各种场合，特别是对博物馆的消防，古建筑群。具有广阔的应用前景。

1外文文献翻译原文及译文汇总

华北电力大学科技学院 毕业设计（论文）附件 外文文献翻译 学号：121912020115姓名：彭钰钊 所在系别：动力工程系专业班级：测控技术与仪器12K1指导教师：李冰 原文标题：Infrared Remote Control System Abstract 2016 年 4 月 19 日

红外遥控系统 摘要 红外数据通信技术是目前在世界范围内被广泛使用的一种无线连接技术，被众多的硬件和软件平台所支持。红外收发器产品具有成本低，小型化，传输速率快，点对点安全传输，不受电磁干扰等特点，可以实现信息在不同产品之间快速、方便、安全地交换与传送，在短距离无线传输方面拥有十分明显的优势。红外遥控收发系统的设计在具有很高的实用价值，目前红外收发器产品在可携式产品中的应用潜力很大。全世界约有1亿5千万台设备采用红外技术，在电子产品和工业设备、医疗设备等领域广泛使用。绝大多数笔记本电脑和手机都配置红外收发器接口。随着红外数据传输技术更加成熟、成本下降，红外收发器在短距离通讯领域必将得到更广泛的应用。 本系统的设计目的是用红外线作为传输媒质来传输用户的操作信息并由接收电路解调出原始信号，主要用到编码芯片和解码芯片对信号进行调制与解调，其中编码芯片用的是台湾生产的PT2262，解码芯片是PT2272。主要工作原理是：利用编码键盘可以为PT2262提供的输入信息，PT2262对输入的信息进行编码并加载到38KHZ的载波上并调制红外发射二极管并辐射到空间，然后再由接收系统接收到发射的信号并解调出原始信息，由PT2272对原信号进行解码以驱动相应的电路完成用户的操作要求。 关键字：红外线；编码；解码；LM386；红外收发器。 1 绪论

外文文献翻译ZigBee：无线技术-低功耗传感器网络

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文献出处：Thronson P. Toward Comprehensive Reform of America’s Emergency Law Regime [J]. University of Michigan Journal of Law Reform, 2013, 46(2). 原文 TOWARD COMPREHENSIVE REFORM OF AMERICA’S EMERGENCY LAW REGIME Patrick A. Thronson Unbenownst to most Americans, the United States is presently under thirty presidentially declared states of emergency. They confer vast powers on the Executive Branch, including the ability to financially incapacitate any person or organization in the United States, seize control of the nation’s communications infrastructure, mobilize military forces, expand the permissible size of the military without congressional authorization, and extend tours of duty without consent from service personnel. Declared states of emergency may also activate Presidential Emergency Action Documents and other continuity-of-government procedures, which confer powers on the President—such as the unilateral suspension of habeas corpus—that appear fundamentally opposed to the American constitutional order.

通信工程项目毕业材料外文翻译

用于多跳认知无线电网络的分布式网络编码控制信道 Alfred Asterjadhi等著 1 前言 大多数电磁频谱由政府机构长期指定给公司或机构专门用于区域或国家地区。由于这种资源的静态分配，许可频谱的许多部分在许多时间和/或位置未使用或未被充分利用。另一方面，几种最近的无线技术在诸如IEEE802.11，蓝牙，Zigbee之类的非许可频段中运行，并且在一定程度上对WiMAX进行操作;这些技术已经看到这样的成功和扩散，他们正在访问的频谱- 主要是2.4 GHz ISM频段- 已经过度拥挤。为了为这些现有技术提供更多的频谱资源，并且允许替代和创新技术的潜在开发，最近已经提出允许被许可的设备（称为次要用户）访问那些许可的频谱资源，主要用户未被使用或零星地使用。这种方法通常被称为动态频谱接入（DSA），无线电设备发现和机会性利用未使用或未充分利用的频谱带的能力通常称为认知无线电（CR）技术。 DSA和CR最近都引起了无线通信和网络界的极大关注。通常设想两种主要应用。第一个是认知无线接入（CW A），根据该认知接入点，认知接入点负责识别未使用的许可频谱，并使用它来提供对次用户的接入。第二个应用是我们在这个技术中研究的应用，它是认知自组织网络（CAN），也就是使用 用于二级用户本身之间通信的无许可频谱，用于诸如点对点内容分发，环境监控，安全性等目的，灾难恢复情景通信，军事通信等等。 设计CAN系统比CW A有更多困难，主要有两个原因。第一是识别未使用的频谱。在CW A中，接入点的作用是连接到互联网，因此可以使用简单的策略来推断频谱可用性，例如查询频谱调节器在其地理位置的频谱可用性或直接与主用户协商频谱可用性或一些中间频谱经纪人另一方面，在CAN中，与频谱调节器或主要用户的缺乏直接通信需要二级用户能够使用检测技术自己识别未使用的频谱。第二个困难是辅助用户协调媒体访问目的。在CW A中存在接入点和通常所有二级用户直接与之通信（即，网络是单跳）的事实使得直接使用集中式媒体接入控制（MAC）解决方案，如时分多址（TDMA）或正交频分多址（OFDMA）。相反，预计CAN将跨越多跳，缺少集中控制器;而对于传统的单通道多跳自组织网络而言，这个问题的几个解决方案是已知的，因为假设我们处理允许设备访问的具有成

英文翻译与英文原文.陈--

翻译文献：INVESTIGATION ON DYNAMIC PERFORMANCE OF SLIDE UNIT IN MODULAR MACHINE TOOL （对组合机床滑台动态性能的调查报告） 文献作者：Peter Dransfield, 出处：Peter Dransfield, Hydraulic Control System-Design and Analysis of TheirDynamics, Springer-Verlag, 1981 翻译页数：p139—144 英文译文： 对组合机床滑台动态性能的调查报告 【摘要】这一张纸处理调查利用有束缚力的曲线图和状态空间分析法对组合机床滑台的滑动影响和运动平稳性问题进行分析与研究，从而建立了滑台的液压驱动系统一自调背压调速系统的动态数学模型。通过计算机数字仿真系统，分析了滑台产生滑动影响和运动不平稳的原因及主要影响因素。从那些中可以得出那样的结论，如果能合理地设计液压缸和自调背压调压阀的结构尺寸. 本文中所使用的符号如下： s1-流源，即调速阀出口流量； S el—滑台滑动摩擦力 R一滑台等效粘性摩擦系数： I1—滑台与油缸的质量 12—自调背压阀阀心质量 C1、c2—油缸无杆腔及有杆腔的液容； C2—自调背压阀弹簧柔度； R1, R2自调背压阀阻尼孔液阻， R9—自调背压阀阀口液阻 S e2—自调背压阀弹簧的初始预紧力； I4, I5—管路的等效液感 C5、C6—管路的等效液容： R5, R7-管路的等效液阻； V3, V4—油缸无杆腔及有杆腔内容积； P3, P4—油缸无杆腔及有杆腔的压力 F—滑台承受负载， V—滑台运动速度。本文采用功率键合图和状态空间分折法建立系统的运动数学模型，滑台的动态特性可以能得到显著改善。

污水处理外文翻译(带原文)

提高塔式复合人工湿地处理农村生活污水的 脱氮效率1 摘要： 努力保护水源，尤其是在乡镇地区的饮用水源，是中国污水处理当前面临的主要问题。氮元素在水体富营养化和对水生物的潜在毒害方面的重要作用，目前废水脱氮已成为首要关注的焦点。人工湿地作为一种小型的，处理费用较低的方法被用于处理乡镇生活污水。比起活性炭在脱氮方面显示出的广阔前景，人工湿地系统由于溶解氧的缺乏而在脱氮方面存在一定的制约。为了提高脱氮效率，一种新型三阶段塔式混合湿地结构----人工湿地（thcw）应运而生。它的第一部分和第三部分是水平流矩形湿地结构，第二部分分三层，呈圆形，呈紊流状态。塔式结构中水流由顶层进入第二层及底层，形成瀑布溢流，因此水中溶解氧浓度增加，从而提高了硝化反应效率，反硝化效率也由于有另外的有机物的加入而得到了改善，增加反硝化速率的另一个原因是直接通过旁路进入第二部分的废水中带入的足量有机物。常绿植物池柏（Taxodium ascendens），经济作物蔺草（Schoenoplectus trigueter），野茭白（Zizania aquatica），有装饰性的多花植物睡莲（Nymphaea tetragona），香蒲（Typha angustifolia）被种植在湿地中。该系统对总悬浮物、化学需氧量、氨氮、总氮和总磷的去除率分别为89%、85%、83%、83% 和64%。高水力负荷和低水力负荷（16 cm/d 和32 cm/d）对于塔式复合人工湿地结构的性能没有显著的影响。通过硝化活性和硝化速率的测定，发现硝化和反硝化是湿地脱氮的主要机理。塔式复合人工湿地结构同样具有观赏的价值。 关键词： 人工湿地；硝化作用；反硝化作用；生活污水；脱氮；硝化细菌；反硝化细菌 １. 前言 对于提高水源水质的广泛需求，尤其是提高饮用水水源水质的需求是目前废水深度处理的技术发展指向。在中国的乡镇地区，生活污水是直接排入湖泊、河流、土壤、海洋等水源中。这些缺乏处理的污水排放对于很多水库、湖泊不能达到水质标准是有责任的。许多位于中国的乡镇地区的社区缺乏足够的生活污水处理设备。由于山区地形、人口分散、经济基础差等原因，废水的收集和处理是很成问题的。由于资源短缺，经济欠发达地区所采取的废水处理技术必须低价高效，并且要便于施用，能量输入及维护费用较低，而且要保证出水能达标。建造在城市中基于活性污泥床的废水集中处理厂，对于小乡镇缺乏经济适用性，主要是由于污水收集结构的建造费用高。 1Ecological Engineering，Fen xia ，Ying Li。

外文翻译

图 1. 感测节点的构建模块 火灾探测装置的设计建立在2个印刷电路板上。其中最简单的一种火灾探测电路组成应该包括一个触摸按钮和一个蜂鸣器用来处理和控制，主电路板指示灯，数据处理和无线数据用来传输。 主电路板是传感装置中最重要的一部分，因为它测量所有的烟雾、气体和温度，并将它们发送到控制中心作为报警信号。适当的能量处理要求电子传感器具备低功耗的微控制器，空调接口和收发器。单片机芯片选择的是pic24fj128ga306（钱德勒，亚利桑那州，美国）。无线模块与交换数据的IEEE 802.15.4标准通过无线基站节点在868兆赫以下。该基站节点作为传感器网络和用户（或办公室，如果系统是用于工业应用）之间的网关。电源由一节AA型锂cr123-3v 1600 mAh电池构成。一个拥有自主产权的传感装置，从硬件的设计，再到作出选择，都必须确保功能齐全，低功耗。此外，该软件还集成了节能模式。电池能够持续5年左右。 无线模块：基于芯片的无线模块是一个低功耗设备可用的mrf89xa收发器。mcp9700a 温度传感器是一种低成本、低功耗的模拟传感器，不需要额外的信号调理电路。电压输出直接连接到ADC输入单片机。该传感器用于测量应用程序的温度变化。 烟雾传感器：这种传感器拥有光电检测烟雾技术和光散射原理运作。使用一束由sfh4551发光二极管（LED）发出的光从欧司朗（雷根斯堡，Baviera，德国）在暗室，防止接收驱动（从一个sfh2500欧司朗光电二极管）检测由黑材料由于光的吸收光的通道。在该腔室中，当烟雾粒子进入光路径时，光照到粒子上，并被反射到光敏装置上，以提醒微控制器。图2显示了腔室的几何形状。

5G无线通信网络中英文对照外文翻译文献

5G无线通信网络中英文对照外文翻译文献(文档含英文原文和中文翻译)

翻译： 5G无线通信网络的蜂窝结构和关键技术 摘要 第四代无线通信系统已经或者即将在许多国家部署。然而，随着无线移动设备和服务的激增，仍然有一些挑战尤其是4G所不能容纳的，例如像频谱危机和高能量消耗。无线系统设计师们面临着满足新型无线应用对高数据速率和机动性要求的持续性增长的需求，因此他们已经开始研究被期望于2020年后就能部署的第五代无线系统。在这篇文章里面，我们提出一个有内门和外门情景之分的潜在的蜂窝结构，并且讨论了多种可行性关于5G无线通信系统的技术，比如大量的MIMO技术，节能通信，认知的广播网络和可见光通信。面临潜在技术的未知挑战也被讨论了。 介绍 信息通信技术（ICT）创新合理的使用对世界经济的提高变得越来越重要。无线通信网络在全球ICT战略中也许是最挑剔的元素，并且支撑着很多其他的行业，它是世界上成长最快最有活力的行业之一。欧洲移动天文台（EMO）报道2010年移动通信业总计税收1740亿欧元,从而超过了航空航天业和制药业。无线技术的发展大大提高了人们在商业运作和社交功能方面通信和生活的能力无线移动通信的显著成就表现在技术创新的快速步伐。从1991年二代移动通信系统(2G)的初次登场到2001年三代系统（3G）的首次起飞，无线移动网络已经实现了从一个纯粹的技术系统到一个能承载大量多媒体内容网络的转变。4G无线系统被设计出来用来满足IMT-A技术使用IP面向所有服务的需求。在4G系统中，先进的无线接口被用于正交频分复用技术（OFDM），多输入多输出系统（MIMO）和链路自适应技术。4G无线网络可支持数据速率可达1Gb/s的低流度，比如流动局域无线访问，还有速率高达100M/s的高流速，例如像移动访问。LTE系统和它的延伸系统LTE-A，作为实用的4G系统已经在全球于最近期或不久的将来部署。 然而，每年仍然有戏剧性增长数量的用户支持移动宽频带系统。越来越多的

外文翻译原文

204/JOURNAL OF BRIDGE ENGINEERING/AUGUST1999

JOURNAL OF BRIDGE ENGINEERING /AUGUST 1999/205 ends.The stress state in each cylindrical strip was determined from the total potential energy of a nonlinear arch model using the Rayleigh-Ritz method. It was emphasized that the membrane stresses in the com-pression region of the curved models were less than those predicted by linear theory and that there was an accompanying increase in ?ange resultant force.The maximum web bending stress was shown to occur at 0.20h from the compression ?ange for the simple support stiffness condition and 0.24h for the ?xed condition,where h is the height of the analytical panel.It was noted that 0.20h would be the optimum position for longitudinal stiffeners in curved girders,which is the same as for straight girders based on stability requirements.From the ?xed condition cases it was determined that there was no signi?cant change in the membrane stresses (from free to ?xed)but that there was a signi?cant effect on the web bend-ing stresses.Numerical results were generated for the reduc-tion in effective moment required to produce initial yield in the ?anges based on curvature and web slenderness for a panel aspect ratio of 1.0and a web-to-?ange area ratio of 2.0.From the results,a maximum reduction of about 13%was noted for a /R =0.167and about 8%for a /R =0.10(h /t w =150),both of which would correspond to extreme curvature,where a is the length of the analytical panel (modeling the distance be-tween transverse stiffeners)and R is the radius of curvature.To apply the parametric results to developing design criteria for practical curved girders,the de?ections and web bending stresses that would occur for girders with a curvature corre-sponding to the initial imperfection out-of-?atness limit of D /120was used.It was noted that,for a panel with an aspect ratio of 1.0,this would correspond to a curvature of a /R =0.067.The values of moment reduction using this approach were compared with those presented by Basler (Basler and Thurlimann 1961;Vincent 1969).Numerical results based on this limit were generated,and the following web-slenderness requirement was derived: 2 D 36,500a a =1?8.6?34 (1) ? ??? t R R F w ?y where D =unsupported distance between ?anges;and F y =yield stress in psi. An extension of this work was published a year later,when Culver et al.(1973)checked the accuracy of the isolated elas-tically supported cylindrical strips by treating the panel as a unit two-way shell rather than as individual strips.The ?ange/web boundaries were modeled as ?xed,and the boundaries at the transverse stiffeners were modeled as ?xed and simple.Longitudinal stiffeners were modeled with moments of inertias as multiples of the AASHO (Standard 1969)values for straight https://www.wendangku.net/doc/314896616.html,ing analytical results obtained for the slenderness required to limit the plate bending stresses in the curved panel to those of a ?at panel with the maximum allowed out-of-?atness (a /R =0.067)and with D /t w =330,the following equa-tion was developed for curved plate girder web slenderness with one longitudinal stiffener: D 46,000a a =1?2.9 ?2.2 (2) ? ? ? t R f R w ?b where the calculated bending stress,f b ,is in psi.It was further concluded that if longitudinal stiffeners are located in both the tension and compression regions,the reduction in D /t w will not be required.For the case of two stiffeners,web bending in both regions is reduced and the web slenderness could be de-signed as a straight girder panel.Eq.(1)is currently used in the ‘‘Load Factor Design’’portion of the Guide Speci?cations ,and (2)is used in the ‘‘Allowable Stress Design’’portion for girders stiffened with one longitudinal stiffener.This work was continued by Mariani et al.(1973),where the optimum trans-verse stiffener rigidity was determined analytically. During almost the same time,Abdel-Sayed (1973)studied the prebuckling and elastic buckling behavior of curved web panels and proposed approximate conservative equations for estimating the critical load under pure normal loading (stress),pure shear,and combined normal and shear loading.The linear theory of shells was used.The panel was simply supported along all four edges with no torsional rigidity of the ?anges provided.The transverse stiffeners were therefore assumed to be rigid in their directions (no strains could be developed along the edges of the panels).The Galerkin method was used to solve the governing differential equations,and minimum eigenvalues of the critical load were calculated and presented for a wide range of loading conditions (bedding,shear,and combined),aspect ratios,and curvatures.For all cases,it was demonstrated that the critical load is higher for curved panels over the comparable ?at panel and increases with an increase in curvature. In 1980,Daniels et al.summarized the Lehigh University ?ve-year experimental research program on the fatigue behav-ior of horizontally curved bridges and concluded that the slen-derness limits suggested by Culver were too severe.Equations for ‘‘Load Factor Design’’and for ‘‘Allowable Stress Design’’were developed (respectively)as D 36,500a =1?4?192(3)? ?t R F w ?y D 23,000a =1?4 ?170 (4) ? ? t R f w ?b The latter equation is currently used in the ‘‘Allowable Stress Design’’portion of the Guide Speci?cations for girders not stiffened longitudinally. Numerous analytical and experimental works on the subject have also been published by Japanese researchers since the end of the CURT project.Mikami and colleagues presented work in Japanese journals (Mikami et al.1980;Mikami and Furunishi 1981)and later in the ASCE Journal of Engineering Mechanics (Mikami and Furunishi 1984)on the nonlinear be-havior of cylindrical web panels under bending and combined bending and shear.They analyzed the cylindrical panels based on Washizu’s (1975)nonlinear theory of shells.The governing nonlinear differential equations were solved numerically by the ?nite-difference method.Simple support boundary condi-tions were assumed along the curved boundaries (top and bot-tom at the ?ange locations)and both simple and ?xed support conditions were used at the straight (vertical)boundaries.The large displacement behavior was demonstrated by Mi-kami and Furunishi for a range of geometric properties.Nu-merical values of the load,de?ection,membrane stress,bend-ing stress,and torsional stress were obtained,but no equations for design use were presented.Signi?cant conclusions include that:(1)the compressive membrane stress in the circumfer-ential direction decreases with an increase in curvature;(2)the panel under combined bending and shear exhibits a lower level of the circumferential membrane stress as compared with the panel under pure bending,and as a result,the bending moment carried by the web panel is reduced;and (3)the plate bending stress under combined bending and shear is larger than that under pure bending.No formulations or recommendations for direct design use were made. Kuranishi and Hiwatashi (1981,1983)used the ?nite-ele-ment method to demonstrate the elastic ?nite displacement be-havior of curved I-girder webs under bending using models with and without ?ange rigidities.Rotation was not allowed (?xed condition)about the vertical axis at the ends of the panel (transverse stiffener locations).Again,the nonlinear distribu-