Reliable Centralized Control of PMSM

In this paper, we introduce the development methodology of a reliable centralized control applied to a synchronous permanent magnet machine. The proposed system is nonlinear, we linearize around a point of application. The resulting model will then be used to reproduce the dynamic behavior of the machine for a reliable control. The controller is based on the standard h infinite to increase performance, reduce measurement noise, and to tolerate the outage of certain sensors. To illustrate the results, we made a comparison between a standard state feedback control and reliable h infinite robust control. The simulation results shows, that the system in case of technical placements poles loses classic performance in the presence of an outage, that the reliable centralized robust control remain satisfactory performance even in the presence of outage.

Significance of Short Story Cycle in Rachel Joyce’s A Snow Garden and Other Stories: An Analytical Study Using Complexity Theory

Rachel Joyce’s short story collection A Snow Garden and Other Stories (2015) is composed of seven stories which occur during a fortnight of the holiday, Christmas season. The collection uses narrative techniques which make it a unique set of stories. The stories have an urban setting and examine the intricacies of human relationships. The sense of interconnection highlighted by Joyce in the stories elevates it to a short story cycle. A short story cycle consists of individual stories which can stand on their own as complete narratives while also maintaining fictional links running through all the stories. The paper is an attempt to establish A Snow Garden and Other Stories as a short story cycle. It also argues that by narrating the interconnected nature of human lives Joyce’s work is exploring life as a complex system. As a scientific philosophy complexity theory explores the behavior of complex systems including human societies. Complex systems are self-organizing, dynamic, evolving networks that operate without any centralized control, similar to human societies. This paper will apply the principles of complex systems to reveal patterns of human behavior represented in Joyce’s work.

Analysis of the use of transformable elements in intelligent tunnel ventilation systems

All main and auxiliary equipment in the tunnel with an intelligent ventilation system are designed to ensure the safety. These systems “talk” and “listen” to each other, make decisions to switch on/off certain system(s) or part(s) thereof and duly inform the tunnel operator, who is authorized to the centralized control of all systems of necessity. The present article uses the numerical models to assess the efficiency of the transformable elements ensuring safe operation of the tunnels. The idea of their use is based on an artificial increase of the tunnel aerodynamic resistance by means of a flexible element, which will hamper the dissemination of combustion products, but not the movement of people through the tunnel and will help isolate clean and polluted air masses. Such resistance will be used to swiftly divide the tunnel carriageway into smaller sections what will help extinguish the fire as early as at its initial stage, prolong the evacuation time and save lives during the strong uncontrollable fires. As for the compact transformable element, it can be used in both, the operating and the planned tunnels, as it in practice does not reduce the volume of valuable underground space.

Security Techniques in MANET: A Study

MANET (mobile ad hoc network) is considered to be a network with no centralized control. This network typically faces two major challenges related to routing and security. Both these issues affect the performance of this network to a large extent. The black hole attack belongs to the category of active attacks that are launched to reduce the network throughput and other parameters. The research works carried out in the past used different techniques to isolate malicious nodes, but with the inclusion of extra hardware and software tools. The various techniques for the security in MANET are analyzed in terms of certain parameters. Keywords: MANET, Black Hole, Security Techniques

Design and Implementation of Distributed Controller Clustering for Solving the Issue of Single Failure in SDN Networks

Software-Defined Networks (SDN) It is a centralized control structure in the network that opens up new possibilities that did not exist before. The significant characteristic of this innovative approach is the focus on the capability of proposing networks of high dynamicity and programmability to transform the intelligence of underlying systems to the networks via controllers. The main issue of the SDN approach is found in its security, mainly due to its central-controlling architecture since the entire network is controlled from a central point. This makes it very vulnerable to single-point failure. In this paper, a fully Distributed SDN controller is proposed for solving the one point failure which exists within the single SDN controller. In general, the concept involves forming cluster of distributed controllers whereby each controller controls its domain and can thereby share the load within the network. The experimental results of the proposed system show an increase and enhancement in the performance of the network. The single-point failure issues have been overcome. The throughput of the proposed system increased with 20% while the packet loss rate was minimize with 33%.

Efficient Task Scheduling and Fair Load Distribution Among Federated Clouds

The federated cloud is the future generation of cloud computing, allowing sharing of computing and storage resources, and servicing of user tasks among cloud providers through a centralized control mechanism. However, a great challenge lies in the efficient management of such federated clouds and fair distribution of the load among heterogeneous cloud providers. In our proposed approach, called QPFS_MASG, at the federated cloud level, the incoming tasks queue are partitioned in order to achieve a fair distribution of the load among all cloud providers of the federated cloud. Then, at the cloud level, task scheduling using the Modified Activity Selection by Greedy (MASG) technique assigns the tasks to different virtual machines (VMs), considering the task deadline as the key factor in achieving good quality of service (QoS). The proposed approach takes care of servicing tasks within their deadline, reducing service level agreement (SLA) violations, improving the response time of user tasks as well as achieving fair distribution of the load among all participating cloud providers. The QPFS_MASG was implemented using CloudSim and the evaluation result revealed a guaranteed degree of fairness in service distribution among the cloud providers with reduced response time and SLA violations compared to existing approaches. Also, the evaluation results showed that the proposed approach serviced the user tasks with minimum number of VMs.

Discussion on Integrated Modeling Technology of New Generation Centralized Control Station Equipment Monitoring System

At present, the substation SCD model mainly aims at the modeling of primary equipment and secondary equipment, and the description of auxiliary equipment and substation area model is missing. According to the characteristics of equipment monitoring of the new generation centralized control station, the description of auxiliary equipment model and area model needs to be added to the original IEC61850 standard. In the first mock exam station, the current business requirements of centralized control station are analyzed. A unified model structure of master station is designed. Based on the definition of IEC61850 standard, a method and example of extending auxiliary device model and regional model are given. The proposed auxiliary equipment and area modeling method based on IEC61850 standard can make up for the shortcomings of the original standard, support the equipment monitoring of the new generation centralized control station and realize rich application functions.