Application Research and Implementation of the CORBA-Based Web Distributed Network Management System

The distributed management has become an important tendency of development for the NMS (Network Management System) with the development of Internet. Based on the analysis of CORBA (Conmon Object Request Broker Architecture) technique, we mainly discuss about the applicability of the approach by which CORBA combined with Java has been applied to the system model and Web architecture: and address the applied frame and the interface definitions that are the, key technologies for implementing the Distributed Object Computing (DOC). In addition, we also conduct the research on its advantages and disadvantages and further expected improvements. Key words distributed Web network management - CORBA - Java CLC number TP 393.07 Foundation item: Supported by the QTNG (Integrated Network Management System) Project Foundation and QT-NMS (SDH NMS) Project Foundation of Wuhan Qingtian Information Industry Co., LTD of Hubei of China (SDH.001)Biography: WANG Feng (1979-), male Master candidate, research direction: administration of network and software engineering.

Design and Implementation of an Open Network Security Management Platform

In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it.

A New Approach for Database Fragmentation and Allocation to Improve the Distributed Database Management System Performance

The efficiency and performance of Distributed Database Management Systems (DDBMS) is mainly measured by its proper design and by network communication cost between sites. Fragmentation and distribution of data are the major design issues of the DDBMS. In this paper, we propose new approach that integrates both fragmentation and data allocation in one strategy based on high performance clustering technique and transaction processing cost functions. This new approach achieves efficiently and effectively the objectives of data fragmentation, data allocation and network sites clustering. The approach splits the data relations into pair-wise disjoint fragments and determine whether each fragment has to be allocated or not in the network sites, where allocation benefit outweighs the cost depending on high performance clustering technique. To show the performance of the proposed approach, we performed experimental studies on real database application at different networks connectivity. The obtained results proved to achieve minimum total data transaction costs between different sites, reduced the amount of redundant data to be accessed between these sites and improved the overall DDBMS performance.

Synergetic optimization operation method for distribution network based on SOP and PV

The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices that can flexibly control active and reactive power flows.With the exception of active power output,photovoltaic(PV)devices can provide reactive power compensation through an inverter.Thus,a synergetic optimization operation method for SOP and PV in a distribution network is proposed.A synergetic optimization model was developed.The voltage deviation,network loss,and ratio of photovoltaic abandonment were selected as the objective functions.The PV model was improved by considering the three reactive power output modes of the PV inverter.Both the load fluctuation and loss of the SOP were considered.Three multi-objective optimization algorithms were used,and a compromise optimal solution was calculated.Case studies were conducted using an IEEE 33-node system.The simulation results indicated that the SOP and PVs complemented each other in terms of active power transmission and reactive power compensation.Synergetic optimization improves power control capability and flexibility,providing better power quality and PV consumption rate.

Threshold-Based Software-Defined Networking(SDN)Solution for Healthcare Systems against Intrusion Attacks

The healthcare sector holds valuable and sensitive data.The amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast pace.Due to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and monitoring.In this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe attacks.These attacks reduce network performance,causing the degradation of different key performance indicators(KPIs)or,in the worst cases,a network failure which can threaten human lives.This can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or m-health.In this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various scenarios.We propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS attack.We then evaluate the accuracy and performance of the proposed TBDC approach.Our technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.

Planning Management of Multiagent-based Distributed Open Computing Environment Model

his paper examines planning management problems in a Multiagentbased Distributed Open Computing Environment Model (MDOCEM). First the meaning of planning management in MDOCEM is introduced, and then a formal method to describe the associated task partition problems is presented, and a heuristic algorithm which gives an approximate optimum solution is given. Finally the task coordination and integration of execution results are discussed.

Analytical Load Balancing Model in Distributed Open Flow Controller System

The Software Defined Network (SDN) is a concept based on a decoupling between the control plan and the data plan of a network. Thus, the network becomes programmable and can be coupled to the business applications of the users. The study that is discussed in this article looks at load planning and balancing in distributed controllers. To do this, a model and theoretical methods of performance evaluation related to appropriate software tools, to predict and control the quality of service offered to users is exposed. This paper exposed also a distributed architecture of controllers and then a module based on an adaptive load balancing algorithm that is fault tolerant and fluctuates controller loads. The experiments show a significant gain in efficiency of our solution.

Dynamic Cluster Key Management Scheme on Wireless Sensor Networks

Wireless sensor networks are open architectures, so any potential threat can easily intercept, wiretap and counterfeit the information. Therefore, the safety of WSN is very important. Since any single key system cannot guarantee the security of the wireless sensor network for communications, this paper introduces a hierarchical key management scheme based on the different abilities of different sensor nodes in the clustered wireless sensor network. In this scheme, the nodes are distributed into several clusters, and a cluster head must be elected for each cluster. Private communication between cluster heads is realized through the encryption system based on the identity of each head while private communication between cluster nodes in a same cluster head is achieved through the random key preliminary distribution system. Considering the characteristics of WSN, we adopt dynamic means called dynamic cluster key management scheme to deal with master key, so master key will be updated according to the changed dynamic network topology. For cluster head node plays a pivotal role in this scheme, a trust manage-ment system should be introduced into the election of the cluster head which will exclude the malicious node from outside the cluster, thus improve the whole network security.

An Advanced Energy Management System

A brief outline of Energy Management System (EMS) in China is given and OPEN-2000 EMS, combined with the novel technique of computer science, is introduced. The system has been developed by Power System Control Division of NARI and put into operation in the middle of 1998.

Review of Key Management Mechanisms in Wireless Sensor Networks

Recent advancements in wireless communication and microchip techniques have accelerated the development of wireless sensor networks (WSN). Key management in WSN is a critical and challenging problem because of the inner characteristics of sensor networks: deployed in hostile environments, limited resource and ad hoc nature. This paper investigates the constraints and special requirements of key management in sensor network environment, and some basic evaluation metrics are introduced. The key pre-distribution scheme is thought as the most suitable solution for key management problem in wireless sensor networks. It can be classified into four classes: pure probabilistic key pre-distribution, polynomial-based, Blom's matrix-based, and deterministic key pre-distribution schemes. In each class of methods, the related research papers are discussed based on the basic evaluation metrics. Finally, the possible research directions in key management are discussed.

GIS Enabled Condition Based Asset Management of Gas Distribution Network: A Case Study of Shahdara, Lahore Pakistan

World energy consumption increased by 56 percent, from 524 quadrillion Btu in 2010 to 820 quadrillion Btu in 2040. The increased demand in energy consumption is fulfilled by different renewable and non-renewable sources such as petroleum, natural gas, electricity, nuclear etc. Natural gas is one of the most important sources of energy. SNGPL has been managing a 94,263 km long gas pipelines network covering approximately the northern part of Pakistan. In this paper we have presented the use of condition based maintenance (CBM) management techniques with a?geographical information system (GIS) for asset management of a gas distribution network of?SNGPL. The continuous monitoring and updating of asset data reveal where the assets are located and which needs maintenance or which lies in critical condition. The system helps to save time and reduce visits to the sites and labour reduction.

Conflict and Emergency Management in a Post-Liberal World

The world is steadily moving to the post-liberal order with the urgent need of novel organizational and security approaches,also new levels of international cooperation,in order to support its stability and prosperity.The developed high-level Spatial Grasp Technology(SGT)and its Spatial Grasp Language(SGL)are briefed which may be particularly useful for solving numerous conflicts and crises problems emerging in different areas during this transitional period,in both local and global scale.SGT employs unlimited spatial scenario mobility and parallel holistic matching of distributed systems,with numerous communicating SGL interpreters potentially installed worldwide.Basic network creation and management operations are described in SGL which may operate on top of existing communication systems or serve individually as high level network protocols in case of non-local crises and disasters.Different operations on social networks are presented in SGL including finding strongest and weakest components with resultant changing of network topologies,also determining distances between different communities for preventing and predicting social conflicts.Fully distributed analysis,and tracing and simulation of multiple mobile objects in distributed spaces with complex routes are shown in SGL related to cruise missiles,defence objects and debris in outer space,as well as massively moving refugees through international borders.The proposed technology had trial implementations and applications in different countries,and its latest version can be readily installed by agreement on any platforms needed.

基于Open DSS的配电网低电压问题治理优化策略研究

电压质量低和系统网损较大是困扰偏远地区配电系统的两个主要问题,也是近几年配电网研究的重点。基于美国电科院(EPRI)开发的Open Distribution System Simulator(Open DSS)平台,进行了三相不平衡配电系统的潮流计算,分析了三相平衡负荷与不平衡负荷对电压和有功网损的影响。以Matlab为平台,设计了Open DSS的COM接口,使得在Matlab程序中能够反复调取Open DSS对配电网进行三相潮流计算,由此建立了配电网无功优化和低电压治理决策模型,将电压分段罚函数引入扩展的无功优化目标函数中,并将高斯罚函数用于处理无功优化变量,使得最终得到的解尽可能地逼近离散值。基于粒子群优化算法(PSO)实现了无功优化问题的求解。实际仿真算例验证了所建立的无功优化模型和算法的有效性与可行性。

HP Open View网管平台二次开发及工程应用

在阐述HPOpenView网络管理开发平台体系结构的基础上,详细分析了基于OpenView网管平台进行二次开发的原理,并说明了基于HPOpenView网管系统集成的方式和一般开发步骤。通过一个卫星会议电视系统网络管理应用开发的例子,说明了HPOpenView在工程中的实际应用,以及具体的二次开发的方法。最后,指出在HPOpenView网络管理平台上进行二次开发来实现网管应用的优势和对企业网络管理的现实意义。

A Privacy-preserving Energy Management System Based on Homomorphic Cryptosystem for IoT-enabled Active Distribution Network

Active distribution network(ADN),as a typically cyber-physical system,develops with the evolution of Internet of Things(IoTs),which makes the network vulnerable to cybersecurity threats.In this paper,the eavesdropping attacks that lead to privacy breaches are addressed for the IoT-enabled ADN.A privacy-preserving energy management system(EMS)is proposed and empowered by secure data exchange protocols based on the homomorphic cryptosystem.During the information transmission among distributed generators and load customers in the EMS,private information including power usage and electricity bidding price can be effectively protected against eavesdropping attacks.The correctness of the final solutions,e.g.,optimal market clearing price and unified power utilization ratio,can be deterministically guaranteed.The simulation results demonstrate the effectiveness and the computational efficiency of the proposed homomorphically encrypted EMS.

A Clustering-tree Topology Control Based on the Energy Forecast for Heterogeneous Wireless Sensor Networks

How to design an energy-efficient algorithm to maximize the network lifetime in complicated scenarios is a critical problem for heterogeneous wireless sensor networks (HWSN). In this paper, a clustering-tree topology control algorithm based on the energy forecast (CTEF) is proposed for saving energy and ensuring network load balancing, while considering the link quality, packet loss rate, etc. In CTEF, the average energy of the network is accurately predicted per round (the lifetime of the network is denoted by rounds) in terms of the difference between the ideal and actual average residual energy using central limit theorem and normal distribution mechanism, simultaneously. On this basis, cluster heads are selected by cost function (including the energy, link quality and packet loss rate) and their distance. The non-cluster heads are determined to join the cluster through the energy, distance and link quality. Furthermore, several non-cluster heads in each cluster are chosen as the relay nodes for transmitting data through multi-hop communication to decrease the load of each cluster-head and prolong the lifetime of the network. The simulation results show the efficiency of CTEF. Compared with low-energy adaptive clustering hierarchy (LEACH), energy dissipation forecast and clustering management (EDFCM) and efficient and dynamic clustering scheme (EDCS) protocols, CTEF has longer network lifetime and receives more data packets at base station. © 2014 Chinese Association of Automation.

Multi-source coordinated stochastic restoration for SOP in distribution networks with a two-stage algorithm

After suffering from a grid blackout, distributed energy resources(DERs), such as local renewable energy and controllable distributed generators and energy storage can be used to restore loads enhancing the system’s resilience. In this study, a multi-source coordinated load restoration strategy was investigated for a distribution network with soft open points(SOPs). Here, the flexible regulation ability of the SOPs is fully utilized to improve the load restoration level while mitigating voltage deviations. Owing to the uncertainty, a scenario-based stochastic optimization approach was employed,and the load restoration problem was formulated as a mixed-integer nonlinear programming model. A computationally efficient solution algorithm was developed for the model using convex relaxation and linearization methods. The algorithm is organized into a two-stage structure, in which the energy storage system is dispatched in the first stage by solving a relaxed convex problem. In the second stage, an integer programming problem is calculated to acquire the outputs of both SOPs and power resources. A numerical test was conducted on both IEEE 33-bus and IEEE 123-bus systems to validate the effectiveness of the proposed strategy.

Crowd Energy Management: New Paradigm for Electricity Market

The traditionally centralized approach of electricity networks is progressively undergoing a shift towards a decentralized, distributed structure. The local and crowd-based principle is transforming the existing supply chain and related activities into a value network （VN）. Previous researches on crowd value network concepts focus on the activities of infrastructure and load management and neglect activities that generate collaboration. Collaboration with and within crowds particularly demands a different mindset and management of sharing values, information, benefit, and risks. Furthermore, these concepts must integrate technical, processual, and social aspects. Thus, this article proposes a holistic framework of electricity VN management for crowd energy. It redefines VN activities for infrastructure and load management while appending VN activities for social electricity handling. Additionally, the framework illustrates the interactions among these three elements and concludes with an adaption cycle for the crowd value network.

Modeling the Proposal of the Simultaneous Purchases and Sales of Electricity and Gas for the Energy Market in a Microgrid Using the Harmony Search Algorithm

The use of different energy carriers together,known as an energy hub,has been a hot topic of research in recent years amongst scientists and researchers.The term energy hub refers to the simultaneous operation of various infrastructures for energy generation and transfer,which has gained momentum in the form of microgrids(MGs).This paper introduces a new strategy for the optimal performance of an MG consisting of different energy carriers for each day.In a smart distribution network(DN),MGs can reduce their own costs in the previous-day market by bidding on sales and purchases.The sales and purchases bidding problem is challenging due to different uncertainties,however.This paper proposes a two-stage strategy for making an optimal bid on electricity sales and purchases with electricity and gas price dependency in the previous-day and real-time markets for an energy hub.In this model,the MG behavior regarding the electricity and gas energy sales/purchase,the simultaneous effects of electricity and gas prices,as well as the energy carriers’dependence on one another are all examined.Due to the inherent uncertainty in the sources of clean energy production,the probabilistic model and the production and reduction scenario have been used in the paper to cover this issue.In the proposed grid,energy sales/purchases are presented in a multi-carrier MG in a two-stage model.This model is solved by using the harmony search algorithm in MATLAB.Numeric results demonstrate the benefits of this model in reducing energy hub costs of operation.

主动配电网潮流的全纯嵌入计算方法

配电网潮流计算是进行配电网规划和运行的重要基础。目前,配电网潮流求解方法主要有牛拉(Newton Raphson,NR)法和前推回代(forward backward substitution,FBS)法两大类,但NR法和FBS法在潮流收敛性和计算效率等方面均存在一定的不足。全纯嵌入法(holomorphic embedding method,HEM)是一种求解非线性潮流方程的新方法,它可以有效避免NR法和FBS法在配电网潮流求解过程中出现的上述问题,但现有HEM未充分考虑配电网中各类型分布式电源(distributed generation,DG)和智能软开关(soft open point,SOP)控制方式的多样性,且未构建计及负荷电压特性和频率特性的潮流模型,难以适用于不同运行模式下配电网潮流计算。针对上述问题,提出一种可求解含多类型DG和SOP且可运行在并网/孤岛模式的主动配电网统一全纯嵌入潮流计算方法。首先,根据负荷静态电压和频率特性,构建计及配电网频率和节点电压影响的负荷节点全纯嵌入潮流模型;其次,根据DG不同的控制方式以及配电网不同的运行模式,将DG所连节点等效为不同节点类型,构建各类DG的全纯嵌入潮流模型;再次,考虑SOP不同控制方式,构建SOP全纯嵌入潮流模型;从次,依据全纯嵌入潮流模型等式左右两侧同次幂级数系数相等原则,推导配电网各全纯函数幂级数系数的求解递推关系式,进而计算各全纯函数的各项幂级数系数,借助解析延拓理论求取电压和频率逼近值,实现配电网潮流的准确求解;最后,通过修改的IEEE-33节点测试系统和IEEE-123节点测试系统验证所提方法准确性和有效性。