综合供能服务站建设规范的构建与解读

浙江省拟规划建设一批兼具电、气、油等多种能源补给和公共非供能服务功能的综合供能服务站。综合供能服务站的设计和建设尚缺少一种统一标准进行规范化。浙江省首次构建了综合供能服务站的建设规范,编制了浙江省地方标准《综合供能服务站建设规范》(DB 33/T 2136-2018),文章论述了该规范的构建过程、重点条目解读与应用情况,帮助综合供能服务站建设者们更好地理解规范、执行规范,有助于加快和规范综合供能服务站工程的建设,实现电、气、油等能源补给服务同其他各类公共非供能服务相结合形成公共供能服务新模式。

基于海洋能的离岸监测服役件供能系统设计

海洋能作为可再生清洁能源,近年来已有多种转换开发方法与装置设计方案提出,但大多集中于装置原理优劣以及供能量大小对比的研究,缺乏针对海洋公共平台及其服役件供能服务的集分析、设计、智能管理、固联以及安全保护等系统化研究。针对不同尺度的服务对象,文章提出了基于海洋可再生潮流能、波浪能的转换、储备以及服务一体化供能应用系统,分析设计了海洋能转换装置原理,提出总体设计思路。在此基础上,给出了电机效率匹配、供能与数据采集智能管理、多装置集成固联以及极端海况自适应保护分析原则与设计方法。结合现场实验验证系统的有效性,为海洋可再生能源的应用与服务提供帮助和参考。

Information System Functions for SmartGrid Management

The violently penetration of renewables in power supply network leads to situations, by which the offer exceeds the demand. Therefore, it is necessary to include a system for processes＇ management. SmartGrid is a platform over the power supply network. It is represented with its network and services, which also have to be managed. The paper aims to show the second stage of SmartGrid management modeling. It meets heterogeneous requirements of the actors--subscriber without photovoltaics, subscriber with photovoltaics, service provider, network operator, and network elements operator--to service and network management and is oriented to functional areas, covering the life cycle of power supply service： Design, Planning, Installation, Provision, Configuration, Maintenance, Performance, Accounting, Buying Up, Security and Subscriber Control. Functional models for existing networks--telecommunications--are used and they are adapted to power supply. The results are illustrated with three functional areas for service management： Accounting, Buying Up, and Performance. The synthesis of network management functions and network element management functions are similar.

Empowering Conditions for Good Water Governance-a Sustainable Model： Vilanculos Case Study （Mozambique）

This article shows the results of the project Empowering conditions for good water governance-a sustainable model： Vilanculos case study （Mozambique）, co-financed by the European Community. This project had the aim of improving sanitary conditions and increasing economic and financial sustainability of water services for the population of Vilanculos. The project has been developed and deployed with cooperation between Acque del Chiampo （an Italian water utility, near Vicenza）, the University of Brescia and the Vilanculos public water service utility, Empresa Mo^ambicana de Agua （EMA）. The paper reports analytical praxis for water distribution measurements, capable of providing essential data about the water network performances, to assess the eventual need for actions in order to solve possible and effective problems of the water service. These practices involve flow and pressure analyses, pinpointing of the network＇s criticalities and leakages by in-situ inspections along the network, managing the valves together with water service utility, as well as the use of a water distribution model to simulate the effects of the proposed interventions and specific software to automatically register bills and payments.

Modeling and Optimization of Bandwidth Supply Performance for Cloud-Assisted Video Systems under Flash Crowd

The large-scale and sudden video content access such as flash crowds results in huge bandwidth demand,which severely influence user quality of experience and quality of service of video systems.In this paper,we firstly discuss the main reason of generation of flash crowds for video streaming services and analyze key factor for balance recovery between supply and demand of upload bandwidth.We construct two models:bandwidth supply capacity model of video systems and bandwidth demand model of users,which measures usage amount of bandwidth of the cloud.Based on the built models,we further employ a community-based cooperative caching strategy of video resources to promote supply capacity of upload bandwidth of video systems.Extensive tests show how the proposed cooperative caching strategy achieves much better performance results in comparison with original solution.

Impact of public name resolving services on Akamai

To enhance user perceived performance,Akamai' s content distribution network(CDN) utilizes the domain name system(DNS) effectively to redirect users to close-by content replicas over short time scale.The use of DNS redirection has brought a significant advantage to Akamai' s CDN.However,the reliance on DNS also poses a fundamental threat to Akamai' s content distribution model.In particular,systematic evaluation and quantification illustrates the impact of recent emerging public DNS resolving services on Akamai' s CDN,including the degradation of corresponding user perceived performance and the benefit damnification of collaborating internet services providers(ISPs) that host Akamai's edge servers.The measurement demonstrates that a considerable penetration of public DNS resolving services(e.g.,OpenDNS and GoogleDNS) effectively corrupts the Akamai' s serving model,namely the large-scale server distribution and quick DNS redirection.

Intelligent Server Management Framework over Extensible Messaging and Presence Protocol

With the increasing importance of cloud services worldwide, the cloud infrastructure and platform management has become critical for cloud service providers. In this paper, a novel architecture of intelligent server management framework is proposed. In this framework, the communication layer is based on the Extensible Messaging and Presence Protocol (XMPP), which was developed for instant messaging and has been proven to be highly mature and suitable for mobile and large scalable deployment due to its extensibility and efficiency. The proposed architecture can simplify server management and increase flexibility and scalability when managing hundreds of thousands of servers in the cloud era.