Node deployment strategy optimization for wireless sensor network with mobile base station

The optimization of network performance in a movement-assisted data gathering scheme was studied by analyzing the energy consumption of wireless sensor network with node uniform distribution. A theoretically analytical method for avoiding energy hole was proposed. It is proved that if the densities of sensor nodes working at the same time are alternate between dormancy and work with non-uniform node distribution. The efficiency of network can increase by several times and the residual energy of network is nearly zero when the network lifetime ends.

Evaluation of a Mobile Station Electronic Health Record on Documentation Compliance and Nurses’ Attitudes

Electronic Health Record (EHR) Systems have been adopted by healthcare organizations for documentation of patient care. Often these information systems are embedded in mobile nurse stations. As part of assessing the impact of this technology it is important to determine the effect it has on charting compliance and user acceptance. Data were collected at a medical center in Taiwan in two stages. The first stage involved use of a 28-item medical review tool to measure charting compliance in 99 charts before and after implementation of the EHR system. In stage two, a survey was conducted with 709 nurse users to determine their level of mobile EHR acceptance 3 months after this documentation technology was initiated. Results demonstrated that EHR significantly improved documentation compliance in standardized data entry format (name, date, time), abbreviation, content correction/revision, patient care needs, and care goals. Analysis of data from the five categories of a user acceptance survey revealed the following results (based on a 4-point Likert scale): patient care (2.92), nursing efficiency (2.78), education and training (2.98), usability (2.61), and usage benefits (2.87). The study concluded that use of mobile nurse stations with EHR can improve documentation compliance and that although frequent system downtime needs improvement, nurses generally have positive attitudes toward this technology application.

Effects of Exposure to GSM Mobile Phone Base Station Signals on Salivary Cortisol,Alpha-Amylase,and Immunoglobulin A

Objective The present study aimed to test whether exposure to radiofrequency electromagnetic fields （RF-EMF） emitted by mobile phone base stations may have effects on salivary alpha-amylase, immunoglobulin A （IgA）, and cortisol levels. Methods Fifty seven participants were randomly allocated to one of three different experimental scenarios （22 participants to scenario 1, 26 to scenario 2, and 9 to scenario 3）. Each participant went through five 50-minute exposure sessions. The main RF-EMF source was a GSM-900-MHz antenna located at the outer wall of the building. In scenarios 1 and 2, the first, third, and fifth sessions were ＂low＂ （median power flux density 5.2 μW/m^2） exposure. The second session was ＂high＂ （2126.8 μW/m^2）, and the fourth session was ＂medium＂ （153.6 μW/m^2） in scenario 1, and vice versa in scenario 2. Scenario 3 had four ＂low＂ exposure conditions, followed by a ＂high＂ exposure condition. Biomedical parameters were collected by saliva samples three times a session. Exposure levels were created by shielding curtains. Results In scenario 3 from session 4 to session 5 （from ＂low＂ to ＂high＂ exposure）, an increase of cortisol was detected, while in scenarios 1 and 2, a higher concentration of alpha-amylase related to the baseline was identified as compared to that in scenario 3. IgA concentration was not significantly related to the exposure. Conclusions RF-EMF in considerably lower field densities than ICNIRP-gnidelines may influence certain psychobiological stress markers.

Analysis of Lightning Disaster of Eight Mobile Base Stations in a County Suffering Thunderstorm on June 23,2015 and Countermeasures

During the process of thunderstorm in a county on June 23,2015,eight mobile base stations in the region were damaged.The reasons for the damage caused by the thunderstorm were discussed through on-the-spot investigation,and some countermeasures were proposed.

Location correction technique based on mobile communication base station for earthquake population heat map

China has mobile phone penetration rate of over 96.2%.Mobile phone has become the largest Internet terminal for Chinese Internet users.Population geographic distribution in earthquake zones can be got based on mobile phone positioning and map matching.For reducing earthquake black-box stage,we propose a real-time collection,correction and schedule algorithm of population position data by four stream processing environments(Redis,Hbase,Kafka,and Spark Streaming)in this paper.For labeling precisely population geographic distribution on the network map,matching of population geographic coordinates and map coordinates are optimized by sample comparison based on location data of mobile communication base stations and prefecture level cities.The test result shows the proposed system is high efficient and can rapidly respond to any emerging parallel tasks during the earthquake.A high-precision heat map of affected population can be produced and published on-line within 2 min after the devastating earthquake happened.

ZTE Launched First SDR Base Station at GSMA Mobile World Congress 2008

ZTE Corporation ("ZTE"), a leading global provider of telecommunications equipment and network solutions,

Analysis of Dispersed Lightning Stroke around a Mobile Communication Base Station

A case of villagers suffering lightning stroke around the tower of a mobile communication base station was investigated to analyze its reasons,and the countermeasures against lightning stroke were proposed. The results show that the lightning stroke event is related to dispersed lightning stroke. To avoid the damage caused by lightning stroke,it is needed to equip a house in the dispersed lightning stroke zone with lightning protection system and spread lightning protection knowledge among the villagers.

NETWORK MANAGEMENT WITH SECURED MOBILE AGENT

Network management scheme must consider security challenges for the Mobile Agent paradigm to be accepted in the Internet computing world. Techniques to provide security solutions have been proposed and some have achieved good results. For example, it is possible to launch a code with a guarantee that it cannot attack the hosting sites. The main problem remaining, however, is protecting the mobile code against malicious service providers, the host problem. This paper proposed a Mobile Agent management scheme in a hierarchical level that provides to user a reliable and flexible global access to internet/network information services. We further described a protection mechanism to Mobile Agents against malicious hosts. As an effort to address host problems we first identify the kinds of attack that may be performed by malicious hosts, and propose a mechanism to prevent these attacks. At each agent host we introduce a trusted third party entity on each server called Secure Service Station (SSS) to carry out security actions.

Effects of Antenna Tilting on Transmitting Power in Mobile Cellular Communication Systems

Radio resources must be wisely managed, in wireless communication systems, when implementing different multiple access techniques. This perspective is pivotal since the variations in propagation channel are very fast and the system is highly complex due to random and unpredictable movement of mobile users continuously. The complexity in the cellular system periodically contributes to different interference levels, high or low, resulting in the degradation of the system capacity. Transmitter power control is an efficient technique to mitigate the effect of interference under fading conditions, combat the Near-Far problem and conserve the battery life. Several remedial measures—like space diversity, frequency diversity, route diversity, increase in antenna height, antenna tilting, etc.—have been tried by many operators to overcome the debilitating effect of multipath fading in fixed line-of-sight microwave and mobile communication links. Among these remedial measures, diversity techniques have been extensively studied in terms of improvement factor, whereas the concept of antenna tilting is relatively less explored compared with other remedial measures. In this study, the effect of antenna tilting on fixed and mobile communication links is investigated to find out the optimum tilting angles in terms of design parameters, as well as on quality of service (QoS). The paper established that a deviation of more than 1.5o in antenna elevation angle would impact on QoS requirements and seriously affect the quality of signal to be received by the mobile systems.

Electromagnetic Environment Impact of Mobile Communication Iron Tower on Adjacent Building and Its Countermeasures

For several lightning-strike disasters related to base station iron tower of mobile communication carrier operator, disaster-inducing factors were analyzed. The reason was as below： after lightning receptor of base station iron tower of mobile communication carder operator was struck by lightning, electromagnetic radiation was generated in the process lightning current leaking into the ground. In addition, it was lightning scattered- strike phenomenon induced by overhead lightning rod, that is, ground lightning falling density around overhead lightning rod was larger than mean at the site. Finally, some improvement measures were put forward.

A Solution Model to Protect Mobile Agents Against Malicious Host Attack

Within an agent server, the model introduces a trusted third party entity called Secure Service Station(SSS). The SSS is a non\|hardware component and is intended to prevent most attacks performed by malicious hosts, by providing mechanisms that ensure attack detection and provide integrity to mobile agents. This noble technique involves encapsulating partial results obtained on each intermediate host and binding these results together using a hash function, thus forming a strong bonded chain that cannot be compromised. An analytical model to explore the system performance was also developed.

电动汽车集中型充电站选址定容模型

针对充电和换电等单一模式的盲目建设,规划不集中带来的资源利用率低与部分充电需求得不到满足等问题,本文提出一种考虑充电和换电与移动充电的多种充电模式下集中型充电站选址与定容方法。首先,分析不同类型电动汽车的充电行为特性,模拟得到规划区域的充电需求分布;然后,基于最近距离原则采用排队论方法计算电动汽车充电损耗成本,优化移动充电设备自充电时刻,求得电动汽车自充电成本;最后,以集中型充电站建设维护成本、用户损失成本及设备自充电成本总和最小为目标建立选址定容模型,结合某城市部分实际道路网为研究区域,采用遗传算法求解模型,确定规划区域内集中型充电站建设数量、位置及不同设备的配置数量。结果表明:规划区域内建设8座集中型充电站总成本达到最低,充电需求车辆数量与充电功率变化对集中型充电站成本均有较大影响,且优化移动充电设备自充电调度管理,可降低集中型充电站高峰时期32.62%的电网负荷,提高了电网稳定性。

5G/B5G异构网络切换过程分析和移动性管理解决方案

有效的移动性管理对于确保5G异构网络预期的QoS和QoE至关重要。切换过程在移动性管理中起着至关重要的作用。在此过程中的故障可能会对5G通信网络的可靠性、稳定性和连接性产生不利影响。对5G HetNet的切换过程进行了分析,包括5G切换过程步骤、5G HetNet的三层切换、5G HetNet的关键切换参数。此外,针对具体问题,如超高速、负载均衡和小区间干扰,归纳总结了5G HetNet的移动性管理主要解决方案,并提出了5G/B5G HetNet的移动性管理新方法。

数字化技术在5G基站电磁辐射监测中的应用

介绍了一个基站电磁辐射数字化检测平台,该平台利用5G+互联网技术,实现了基站电磁辐射原始监测数据、频谱图的实时上传,以及基站电磁辐射监测的全要素、全流程管理,并结合CNAS实验室认可要求介绍了数字化检测系统投入应用时的注意事项。

车载机动式测控站结构设计

高机动性是电子装备提高战场生存能力的重要手段,本文针对新型机动测控站高机动性以及机动中工作的需求,提出了一种高度集成的一车一站车载机动式测控站,对其从整车布局、人机工程、热设计等多角度进行了论述,其共形相控阵天线阵面的设计理念既保证了系统空域的覆盖,也可以为内部工作人员创造优良的工作环境,通过专业软件对系统天线舱的力、热、磁、噪声等性能的分析评估,证明相关设计可以满足要求,其设计思路可为后续类似系统的研制提供借鉴。

分布式守时架构下的高精度时间比对技术研究

为了实现分布式联合守时系统建立需求,设计了远程时间比对系统,包含卫星共视、卫星双向和光纤双向三种时间比对手段,系统内使用的国产化设备比对精度与进口设备相当,实现了实验室间多手段、高精度钟差测量。使用移动校准站完成了时间比对设备相对零值校准,在相距50 km的实验室间开展长达20天的时间比对,试验结果表明,三种比对手段测量得到两地钟差均值相差小于1 ns,变化趋势相同,变化幅度相近,均可以准确测量得到两地钟差。

主动配电网-充换电站群-智慧社区群分层优化调度策略

为解决配电网、社区、充换电站3个利益主体之间难以保障能量最优交换和信息安全问题,提出一种主动配电网充换电站群智慧社区群的分层优化调度策略。首先,结合用户侧的储能需求和电动汽车充换电站的运行优化需求,在满足配电网经济运行的前提下建立电动汽车充换电站、配电网和社区共同参与的共享储能模式,上层为主动配电网运行模型,下层为社区和充换电站运行模型;其次,考虑各储能充换电站之间的交通流、能量流的时空特性,利用卡车对各电动汽车充换电站间的电池进行灵活调度,建立基于移动式储能车的电池时空共享模型;然后,为解决多主体(即充换电站、配电网、社区)参与的调度框架难以实现总体最优的问题,引入交替方向乘子法(alternating direction method of multipliers,ADMM)设计了社区充换电站配电网的3层能量共享模型;最后使用MATLAB对模型仿真编码求解。仿真结果表明:所提出的策略能够保障共享储能系统中各个主体隐私的安全性和用能的经济性,使能量共享形式更加多样化;可提高储能电池的使用效率和用能经济性,系统总成本降低了18%。

面向光伏电站除尘作业的移动机械臂抗倾覆稳定性研究

对光伏电站移动机械臂倾覆稳定性的研究是其安全、高效作业的前提。采用重力法分析移动机械臂在水平路面和倾斜路面的静态稳定性,以倾覆力矩为标识对移动平台与机械臂耦合状态下的稳定性进行分析,并利用Matlab和Adams仿真验证移动机械臂的稳定性,结果表明移动机械臂在水平路面上进行作业运动时处于稳定状态;通过分析移动机械臂在倾斜路面上的稳定性,确定其可安全操作的最大路面倾斜角度。

移动充电桩选址-路径优化及遗传-RSI两阶段算法

在我国“双碳”政策背景下,考虑载重、电量、充电桩服务能力等约束,构建以最小化总配送距离为目标的移动充电桩选址与电动汽车路径规划模型。随后,设计一种两阶段算法求解模型,第一阶段采用遗传算法规划初始配送路径,第二阶段采用RSI(recharge stations insertion)算法实现充电桩选址及路径调整。基于CVRP基准案例进行求解,结果表明车辆访问充电桩导致的配送距离平均增长率在5%以下。与粒子群和模拟退火作为一阶段的算法对比,遗传-RSI两阶段算法与这两种算法求解结果的Gap值分别为-4.04%和-3.65%。最后对“电耗率”等模型参数进行灵敏度分析。结果表明在物流公司专用电动车配送中,若使用专用充电桩并接受8%以下配送距离增长及相应的充电服务费,可采取移动充电桩选址与路径联合优化模式。