Flexible,thermal processable,self-healing,and fully bio-based starch plastics by constructing dynamic imine network

The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable sources.Starch is desirable for fabricating bioplastic due to its abundance and renewable nature.However,limitations such as brittleness,hydrophilicity,and thermal properties restrict its widespread application.To overcome these issues,covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base reactions.This strategy endowed starch plastic with excellent thermal processability,as evidenced by a low glass transition temperature(T_(g)=20.15℃).Through introducing Priamine with long carbon chains,the starch plastic demonstrated superior flexibility(elongation at break=45.2%)and waterproof capability(water contact angle=109.2°).Besides,it possessed a good thermal stability and self-adaptability,as well as solvent resistance and chemical degradability.This work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics.

基于Zigbee的煤矿安全生产监控系统设计与研究

针对目前有线式煤矿安全监控系统布线繁琐、灵活性差、安装及维护成本高等问题,将无线通信及物联网技术应用至煤矿安全生产监控中,提出了一种基于Zigbee无线传感器网络的煤矿安全监控系统设计方案,对多参数融合检测无线传感器节点及基站传感器节点进行设计,利用无线传感网络自组织、结构灵活等特点弥补目前有线系统缺陷,实现煤矿井下环境参数及人员信息的采集、传输与监控,有效提高煤矿安全生产监控水平。

基于Zigbee技术的无线辐射监测系统的建立

基于Zigbee技术的无线辐射监测系统可对众多辐射监测仪的监测数据进行实时采集和统计分析,无需布线,组网灵活。该辐射监测系统包括多台辐射监测仪及上位机监测平台。辐射监测仪负责测量辐射信息,并将辐射测量结果通过Zigbee模块发送出来。辐射监测平台负责接收辐射测量结果,并将数据在监测平台上进行显示和存储。对辐射监测仪和辐射监测系统进行测试,测试结果表明:辐射监测仪可对在环境本底的基础上增加0.1μSv/h的γ辐射给出可靠报警;辐射监测系统可自动进行无线网络连接,整体运行稳定,数据采集准确,可实现对各个辐射监测仪监测数据的实时采集和存储。

Home control system based on ZigBee wireless sensor networks

A new scheme of the home control system based on ZigBee wireless sensor networks is presented. The design and development of the software and hardware of the proposed system are given. In addition to the basic data acquisition and processing functions, the gateway supports the Bluetooth-based local interface and the general packet radio service （GPRS）-based remote interface. Users on the client service side can use a pocket PC or notebook PC to achieve real-time data acquisition and control instruction implementation, or remotely control the home control system through a mobile phone by sending a short message. The Labview graphical development environment is adopted to create PDA applications running on pocket PCs and monitoring platform established on notebook PCs. Except for the gateway, other nodes in the system work in sleep mode most of the time on the system, and thus it improves the lifetime of the whole system efficiently.

基于ZigBee通信网络的农机作业监测系统设计

首先,介绍了ZigBee通信网络技术,并设计了系统总体设计方案;然后,分别从转速测量模块、振动信号采集模块和割台高度检测设计了系统硬件部分;最后,针对设备节点和协调器两部分设计了ZigBee无线网络传输软件,实现了农机作业监测系统。测试结果表明:系统能够正确采集农机作业参数并通过无线网络发送到云平台,证明系统的可靠性和可行性。

ZigBee无线通信技术在智能家居网络中的应用

ZigBee无线通信技术在智能家居组网中具有重要的应用。为了探究其使用场景和方法,文章首先分析了基于ZigBee的智能家居网络组网方式,其次介绍了接收信号强度指示(Received Signal Strength Indicator,RSSI)算法的测距原理和DV-Hop算法的测点原理,最后针对两种算法的局限性,提出基于阈值的改进定位算法。

基于ZigBee无线传感网络的分簇时间同步算法

在无线传感网络中,时间同步技术在信道分配、数据收发、休眠调度中都有着关键作用。目前已有的时间同步算法,有些同步精度不高,有些需要进行频繁的数据交换导致功耗过大。因此设计出能同时满足高精度和低功耗两个要求的算法势在必行。提出的算法通过改变网络拓扑结构,构造分簇函数,选出簇头,进行分簇。在新的网络拓扑中,协调器与簇头之间通过频偏补偿来保证同步的精度,簇头与成员节点之间通过三次通信消除时延进行时间同步,从而实现全网时间同步。仿真结果表明,整个网络在较低功耗下也能有较高的同步精度。

基于多共引特征的ZigBee无线传感网络节点分类

ZigBee无线传感网络节点数量大、密度高、特征向量复杂,导致节点分类难度上升。在复杂的大差异节点特征中,研究以融合共引节点特征为基础的ZigBee无线传感网络节点分类方法。采集ZigBee无线传感网络节点数据,提取节点的embedding、入度、出度、集聚系数、PageRank值等有共引属性的特征,确定节点共引特征向量。利用搭建的节点分类模型,将提取的共引特征嵌入到模型空间内,通过引入注意力机制及多角度信息的融合完成分类模型的训练,利用训练好的模型对于ZigBee无线传感网络节点进行分类。实验结果表明,所提方法的micro-F1和macro-F1均随着节点的增多而降低,约为95.8、96.3,且并未出现上升的趋势,表明ZigBee无线传感网络节点分类效果好,综合效率高,可靠性强。

A Wireless Sensor Network Solution for Precision Agriculture Based on Zigbee Technology

The article has been retracted due to the investigation of complaints received against it. The Editorial Board found that substantial portions of the text quite like the one published in other journal. The problem is under investigation. This paper published in Vol.4 No.1, 2012, has been removed from this site temporally.

System Performance of Wireless Sensor Network Using LoRa–Zigbee Hybrid Communication

Wireless sensor network(WSN)is considered as the fastest growing technology pattern in recent years because of its applicability in varied domains.Many sensor nodes with different sensing functionalities are deployed in the monitoring area to collect suitable data and transmit it to the gateway.Ensuring communications in heterogeneous WSNs,is a critical issue that needs to be studied.In this research paper,we study the system performance of a heterogeneous WSN using LoRa–Zigbee hybrid communication.Specifically,two Zigbee sensor clusters and two LoRa sensor clusters are used and combined with two Zigbee-to-LoRa converters to communicate in a network managed by a LoRa gateway.The overall system integrates many different sensors in terms of types,communication protocols,and accuracy,which can be used in many applications in realistic environments such as on land,under water,or in the air.In addition to this,a synchronous management software on ThingSpeak Web server and Blynk app is designed.In the proposed system,the token ring protocol in Zigbee network and polling mechanism in LoRa network is used.The system can operate with a packet loss rate of less than 0.5%when the communication range of the Zigbee network is 630 m,and the communication range of the LoRa network is 3.7 km.On the basis of the digital results collected on the management software,this study proves tremendous improvements in the system performance.

The Optimization Study about Fault Self-Healing Restoration of Power Distribution Network Based on Multi-Agent Technology

In order to quickly and accurately locate the fault location of the distribution network and increase the stability of the distribution network,a fault recovery method based on multi-objective optimization algorithm is proposed.The optimization of the power distribution network fault system based on multiagent technology realizes fast recovery of multi-objective fault,solve the problem of network learning and parameter adjustment in the later stage of particle swarm optimization algorithm falling into the local extreme value dilemma,and realize the multi-dimensional nonlinear optimization of the main grid and the auxiliary grid.The system proposed in this study takes power distribution network as the goal,applies fuzzy probability algorithm,simplifies the calculation process,avoids local extreme value,and finally realizes the energy balance between each power grid.Simulation results show that the Multi-Agent Technology enjoys priority in restoring important load,shortening the recovery time of power grid balance,and reducing the overall line loss rate of power grid.Therefore,the power grid fault self-healing system can improve the safety and stability of the important power grid,and reduce the economic loss rate of the whole power grid.

基于ZigBee网络和自适应PSD算法的路灯分布式节能控制方法

当前照明系统缺乏分布式路灯动态化控制,浪费大量能源,为此,提出了基于ZigBee网络和自适应PSD算法的路灯分布式节能控制方法。通过ZigBee网络通信连接系统传感器、控制中心和照明终端,协调设备通信功能,实现信息快速传输储存。利用神经网络处理信号数据,提高系统信号检测和处理效率。在此基础上,利用自适应PSD算法识别路灯信号动态特征,进行自适应信号检测,调节信号数据偏差,精确检测数据结果,增强系统节能控制稳定程度,实现路灯分布式节能控制。由实验结果可知,研究方法将分布式路灯检测精准度提高到99%,熔池宽度稳定在3.5W/mm,具有良好的检测精准度和控制稳定性,可以对路灯进行节能控制。

The ZigBee Based Wireless Sensor and Actor Network in Intelligent Space Oriented to Home Service Robot

In the study of intelligent space oriented to home service robot, an important technology is how to construct an communication network which has the characters of high reliability and easy building. In this paper, based on the characteristics of ZigBee protocol, ZigBee technology is used to construct a wireless sensor and actor network. Several intelligent services based on ZigBee wireless sensor and actor network are shown to certify the reliability of this communication network. ZigBee wireless sensor and actor network builds an information bridge for the components in the intelligent space, the spatially distributed devices are connected together seamlessly. With this network, robot can share the mass information in the intelligent space and improve its performance with 'light-packs', devices in intelligent space, such as lamp, curtain can be controlled autonomously.

A Study on Priority Based ZigBee Network Performance Analysis with Tree Routing Method

The Wireless Sensor Network (WSN) is spatially distributed autonomous sensor to sense special task. WSN like ZigBee network forms simple interconnecting, low power, and low processing capability wireless devices. The ZigBee devices facilitate numerous applications such as pervasive computing, security monitoring and control. ZigBee end devices collect sensing data and send them to ZigBee Coordinator. The Coordinator processes end device requests. The effect of a large number of random unsynchronized requests may degrade the overall network performance. An effective technique is particularly needed for synchronizing available node’s request processing to design a reliable ZigBee network. In this paper, region based priority mechanism is implemented to synchronize request with Tree Routing Method. Riverbed is used to simulate and analyze overall ZigBee network performance. The results show that the performance of the overall priority based ZigBee network model is better than without a priority based model. This research paves the way for further designing and modeling a large scale ZigBee network.

Towards Interference-Aware ZigBee Transmissions in Heterogeneous Wireless Networks

Cross-technology interference(CTI)from diverse wireless networks such as ZigBee,Bluetooth,and Wi-Fi has become a severe problem in the 2.4 GHz Industrial Scientific and Medical(ISM)band.Especially,low power and lossy networks are vulnerable to the signal interferences from other aggressive wireless networks when they perform low power operations to conserve the energy consumption.This paper presents CoSense,which accurately detects ZigBee signals with a reliable signal correlation scheme in the presence of the CTI.The key concept of CoSense is to reduce false wake-ups of low power listening(LPL)by identifying the pre-defined ZigBee signatures.Our scheme is robust in the coexistence environment of diverse wireless technologies since the signal correlation works well in bad wireless channel conditions.It achieves standard compliance and transparency without any hardware and firmware changes.We have implemented CoSense on the Universal Software Radio Peripheral(USRP)platform to verify its feasibility.The experimental exploration reveals that CoSense significantly reduces the false-positive and false-negative rate under typical setting and the additional overhead is negligible.The results show that our scheme saves much energy by up to 63%in dynamic network interference scenarios where low-power ZigBee transmissions are overwhelmed by strong Wi-Fi signal interferences.

Zigbee Based Wireless Sensor and Actuator Network for Service Robot Intelligent Space

Wireless sensor and actuator network is the key technology of service robot intelligent space. This paper is concerned with design and implementation of a ZigBee based wireless sensor and actuator network (hereinafter referred to as ZWSAN), which has been applied in our service robot intelligent space successfully. Firstly, a simplified ZigBee stack applied to ZWSAN is proposed and the primitives of the stack are illustrated after a short overview of ZigBee protocols. Then the implementation of hardware module and software stack is introduced in detail as well as several representative devices integrated into ZWSAN, including environmental sensors for environmental perception, home devices controllers for device control, embedded speech recognition module for speech control, IMU module for abnormal behaviors detection and laser robot control for service robot navigation. An application example is described to demonstrate how the devices in ZWSAN to provide service cooperatively. Finally, we conclude this paper and discuss the future directions.

A WiFi-ZigBee Building Area Network Design of High Traffics AMI for Smart Grid

A WiFi-ZigBee hybrid BAN solution, namely WiZBAN, is proposed and implemented to cater for the development of high traffic AMI for smart grid application. It is important to highlight that the major challenge of WiZBAN is to handle the high density environment which results in heavy traffic loading and weak signal propagation. To overcome the captioned problem, Vertical Backbone Communication (VBC) and Horizontal Floor Communication (HFC) are defined for WiZBAN. The WiZBAN consists of WiZBAN Gateway (WiZGW), WiZBAN Meter Hub (WiZBAN) and WiZBAN In Home Display (WiZIHD) which caters for the smart grids services including smart metering and demand response. The WiZGW is the entrance of WiZBAN and connects WiZBAN to utilities. The WiZGW also teams up with WiZMH to enables VBC. On the other hand, WiZMH serves as the interception point of VBC and HFC. It interacts with smart meters and sets up the HFC together with WiZIHD to provide the user interface for end users. To shorten the transmission time, WiFi is adopted for VBC while ZigBee is applied to HCF to overcome the weak signal propagation. To investigate the performance of WiZBAN, a case study has been conducted based on an existing 23 floor residential building. From the measured and simulated results, the average round trip delay of demand response and smart metering are found to be 0.6 s and 9 s respectively.

Implementation of ZigBee Network Layer Based on AODVjr and Tree Hirarchical Route Algorisms

The basic functions and the relative concepts of ZigBee network are analyzed in this paper. The implementation method of ZigBee network layer is proposed, it includes how to build a new network, add a node to the network, send data and receive data. The distributing address assigning mechanism, the tree hierarchical route algorism and AODVjr algorism are implemented. Finally, the ZigBee network layer protocol is tested.

The Design of Wireless Sensor Network System based on ZigBee Technology

The paper design hardware platform based on network node, and analyze ZigBee protocol architecture and standards of each layer; on based of ZigBee protocol stack, we design the application program of network coordinator and terminal node to realize the data acquisition; design of network system has the characteristics of low cost, small volume, test results show that the mesh topology, network support, can be rapidly deployed, temperature, humidity, light intensity information of the smooth reading environment, that can be used for domestic environmental monitoring field.

基于ZigBee技术的造纸行业仓库系统的设计

为帮助造纸企业智能化周转、调拨和管理纸产品,应用ZigBee技术,完成对造纸行业仓库系统设计。首先,在介绍ZigBee技术相关概念的基础上完成系统架构和系统数据库设计;其次,分别设计货物出入库管理、数据查询、基本资料管理、资料统计、仓库监控等模块;最后,对系统性能进行测试。结果表明,本文系统具有并发能力强、稳定性强、负载均衡性强、安全可靠等特点,符合预期设计标准和要求。