GIS在运营商运维体系中的应用思考

从电信运营商运维的现状出发,深入分析了GIS在电信运维中的应用技术,从GIS在运维中的应用范围、应用特点和对运维效率的提升等角度,对基于GIS的新型运维体系建设进行了探讨。     

可重构服务承载网主动保护算法研究

基于可重构柔性网络(RFNet,reconfigurable flexible network)构建可重构服务承载网(RSCN,reconfigurableservice carrying network)能够为终端用户提供满足业务特性需求的通信服务,有效地解决了传统互联网体系结构面临的困境。鉴于网络故障造成的负面影响,针对RSCN主动保护问题进行了数学建模和理论分析。为了尽量避免重要资源故障给网络带来的影响,设计了资源紧迫度感知的主路径构建子算法RSF-awareMLCA;为了提高RSCN的运行成功率并降低网络链路故障损失,设计了RSCN保护链路构建子算法RPLCA;结合2个子算法,设计了RSCN主动保护构建算法RAPA。最后,分析了算法的复杂度,从RSCN成功运行率、主链路利用率和平均网络链路故障损失3个方面验证了RAPA的优越性。     

Enhancing the Stability of Perovskite Quantum Dots by Encapsulation in Crosslinked Polystyrene Beads via a Swelling–Shrinking Strategy toward Superior Water Resistance

Organic/inorganic hybrid lead halide perovskites are promising optoelectronic materials due to their unique structure, excellent properties, and fascinating potential applications in lighting, photovoltaic, etc. However, perovskite materials are very sensitive to moisture and polar solvent, which greatly hinders their practical applications. Here, highly luminescent perovskite–polystyrene composite beads with uniform morphology are prepared via a simple swelling–shrinking strategy. This process is carried out only in nonpolar toluene and hexane without the addition of any polar reagents. As a result, the as‐prepared composite beads not only retain high luminescence but also exhibit superior water‐resistant property. The composites emit strong luminescence after being immersed into water over nine months. Moreover, even in some harsh environments such as acid/alkali aqueous solution, phosphate buffer solution, and Dulbecco's modified eagle medium biological buffers, they still preserve high luminescence. The applications in light‐emitting diodes and cellular labeling agents are also carried out to demonstrate their ultrastability.     

Novel Iron/Cobalt‐Containing Polypyrrole Hydrogel‐Derived Trifunctional Electrocatalyst for Self‐Powered Overall Water Splitting

Development of efficient, low‐cost, and durable electrocatalysts for the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is of significant importance for many electrochemical devices, such as rechargeable metal–air batteries, fuel cells, and water electrolyzers. Here, a novel approach for the synthesis of a trifunctional electrocatalyst derived from iron/cobalt‐containing polypyrrole (PPy) hydrogel is reported. This strategy relies on the formation of a supramolecularly cross‐linked PPy hydrogel that allows for efficient and homogeneous incorporation of highly active Fe/Co–N–C species. Meanwhile, Co nanoparticles are also formed and embedded into the carbon scaffold during the pyrolysis process, further promoting electrochemical activities. The resultant electrocatalyst exhibits prominent catalytic activities for ORR, OER, and HER, surpassing previously reported trifunctional electrocatalysts. Finally, it is demonstrated that the as‐obtained trifunctional electrocatalyst can be used for electrocatalytic overall water splitting in a self‐powered manner under ambient conditions. This work offers new prospects in developing highly active, nonprecious‐metal‐based electrocatalysts in electrochemical energy devices.     

湿法氧化Al0.85Ga0.15As时SiO2层的保护作用

本文研究了有无氧化硅保护层时Al0.85Ga0.15As层的高温湿法氧化。实验结果表明：氧化硅层对Al0.85Ga0.15As层的高温侧向湿法氧化速率基本无影响;被氧化区域SEM图像的衬度和有氧化硅保护层样品As拉曼峰的缺乏归因于被氧化区域中不存在氧化反应产物As,这有利于提高氧化层的热稳定性;有SiO2保护层样品的发光强度比无SiO2保护层样品的发光强度强的多,且具有SiO2保护层样品的发光峰位和半高全宽与氧化前的样品基本一致,而无SiO2保护层样品的发光峰位红移,半高宽展宽,这是由于氧化硅层阻止了GaAs盖层的氧化。     

Achieving efficient location privacy protection based on cache

With the development of mobile Internet and the popularization of intelligent terminals,location based services(LBS) has been widespread in navigation,social network and other fields.Due to the sensitivity of personal location information,data privacy protection related to location of mobile objects has become the hotspots of research.Considering the openness of the background information,and based on the information cache mechanism,a dummy selection algorithm was proposed to reduce the number of interactions between the user and the untrusted server and combine the k-anonymity to achieve efficient location privacy.Without relying on trusted third party,the scheme can prevent the attackers owned background information from inference attack,and the detail simulation results indicate its effectiveness and efficiency.     

Survey on differential privacy and its progress

With the arrival of the era of big data sharing,data privacy protection issues will be highlighted.Since its introduction in 2006,differential privacy technology has been widely researched in data mining and data publishing.In recent years,Google,Apple and other companies have introduced differential privacy technology into the latest products,and differential privacy technology has become the focus of academia and industry again.Firstly,the traditional centralized model of differential privacy was summarized,from the perspective of analysis of data mining and data released in the differential privacy way.Then the latest local differential privacy regarding data collection and data analysis based on the local model was described,involving crowdsourcing with random response technology,BloomFilter,statistical inference techniques.Finally,the main problems and solutions of differential privacy technology were summarized.     

直流固态功率控制器控制技术

直流固态功率控制器是智能开关装置,采用功率MOS管作为直流负载接通或断开直流电源的开关器件,能够实现过载、短路、超温等保护功能。通过DC-SSPC对直流负载进行远程控制,可随时获知负载的工作模式和运行状态,具备健康诊断和实时监控功能。主要研究了直流固态功率控制器工作原理及主要关键技术,并通过原理样机验证了直流固态功率控制器设计的可行性。     

紫外激光技术在船舶压载水处理系统中的应用

为了航行安全远洋船舶需要注入和排放压载水。压载水中的有害水生物和病原体同时也被搬运,并导致海洋水域环境的污染。控制该污染的核心措施之一是在船上增添压载水处理设备。紫外线激光二极管可以制造产生紫外线的辐射,能穿透细菌、病毒的细胞膜,破坏核酸结构,使之失去繁殖和自我复制能力,达到快速杀菌的效果。紫外激光压载水处理设备杀菌快速,无二次污染,使用安全,占地小,可操作性强,尤其适用于中小型船舶压载水处理系统。