Rеkоnfigurаciја distributivnе mrеžе primеnоm mеtоdе pоmеrајućеg rеgistrа оtvоrеnih prеkidаčа

2021 ◽  
Vol 23 (2) ◽  
pp. 11-16
Author(s):  
Dаrkо Šоšić ◽  
◽  
Тоmislаv Rајić ◽  
Branko Stојаnоvić
Keyword(s):  
Network Performance ◽  
Distribution Network ◽  
Main Idea ◽  
Operating Conditions ◽  
Network Configuration ◽  
Monthly Basis ◽  
Radial Structure ◽  
The Status ◽  
Common Goals ◽  
Limited Service

Reconfiguration of the distribution network is a process of changing the status of individual switch equipment in order to achieve better operating conditions of the distribution network. Performance improvement may relate to a shorter or longer period of time. One of the most common goals in the problem of changing the configuration of the distribution network is to reduce the losses of active power. In this paper, the problem of reconfiguration of the distribution network will be solved by applying the method of moving register of open switches. The main idea of the method is to gradually close normally open branches, whereby it is necessary to open one normally closed branch from the formed loop in order to maintain the radial structure of the network. Due to the wear of the switchgear and its limited-service life, it is not desirable to change the network configuration for each time. This paper will consider achieving the most economical distribution network configuration on a monthly basis.

OPERATIONAL STATE OF BRIDGES OF UKRAINE

2019 ◽  
pp. 57-68
Author(s):  
Larysa Bodnar ◽  
Petro Koval ◽  
Sergii Stepanov ◽  
Liudmyla Panibratets
Keyword(s):  
Management System ◽  
The State ◽  
Operating Conditions ◽  
Bridge Management ◽  
Bridge Management System ◽  
Program Complex ◽  
Operating Condition ◽  
Software Complex ◽  
Automatic Mode ◽  
The Status

A significant part of Ukrainian bridges on public roads is operated for more than 30 years (94 %). At the same time, the traffic volume and the weight of vehicles has increased significantly. Insufficient level of bridges maintenance funding leads to the deterioration of their technical state. The ways to ensure reliable and safe operation of bridges are considered. The procedure for determining the predicted operational status of the elements and the bridge in general, which has a scientific novelty, is proposed. In the software complex, Analytical Expert Bridges Management System (AESUM), is a function that allows tracking the changes in the operational status of bridges both in Ukraine and in each region separately. The given algorithm of the procedure for determining the predicted state of the bridge using a degradation model is described using the Nassie-Schneidermann diagram. The model of the degradation of the bridge performance which is adopted in Ukraine as a normative one, and the algorithm for its adaptation to the AESUM program complex with the function to ensure the probabilistic predicted operating condition of the bridges in the automatic mode is presented. This makes it possible, even in case of unsatisfactory performance of surveys, to have the predicted lifetime of bridges at the required time. For each bridge element it is possible to determine the residual time of operation that will allow predict the state of the elements of the structure for a certain period of time in the future. Significant interest for specialists calls for the approaches to the development of orientated perspective plans for bridge inspection and monitoring of changes in the operational status of bridges for 2009-2018 in Ukraine. For the analysis of the state of the bridge economy, the information is available on the distribution of bridges by operating state related to the administrative significance of roads, by road categories and by materials of the structures. Determining the operating state of the bridge is an important condition for making the qualified decisions as regards its maintenance. The Analytical Expert Bridges Management System (AESUM) which is implemented in Ukraine, stores the data on the monitoring the status of bridges and performs the necessary procedures to maintain them in a reliable and safe operating condition. An important result of the work is the ability to determine the distribution of bridges on the public roads of Ukraine, according to operating conditions established in the program complex of AESUM, which is presented in accordance with the data of the current year. In conditions of limited funding and in case of unsatisfactory performance of surveys, it is possible to make the reasonable management decisions regarding the repair and the reconstruction of bridges. Keywords: bridge management system, operating condition, predicted operating condition, model of degradation, bridge survey plan, highway bridge.

Optimal placement of distributed generation based on DISCO’s additional benefit using self adaptive levy flight based black widow optimization

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Naga Lakshmi Gubbala Venkata ◽  
Jaya Laxmi Askani ◽  
Venkataramana Veeramsetty
Keyword(s):  
Distributed Generation ◽  
Distribution Network ◽  
Additional Benefit ◽  
Operating Conditions ◽  
Optimal Placement ◽  
Lévy Flight ◽  
Black Widow ◽  
Levy Flight ◽  
Simulation Performance ◽  
Self Adaptive

Abstract Optimal placement of Distributed Generation (DG) is a crucial challenge for Distribution Companies (DISCO’s) to run the distribution network in good operating conditions. Optimal positioning of DG units is an optimization issue where maximization of DISCO’s additional benefit due to the installation of DG units in the network is considered to be an objective function. In this article, the self adaptive levy flight based black widow optimization algorithm is used as an optimization strategy to find the optimum position and size of the DG units. The proposed algorithm is implemented in the IEEE 15 and PG & E 69 bus management systems in the MATLAB environment. Based on the simulation performance, it has been found that with the correct location and size of the DG modules, the distribution network can be run with maximum DISCO’s additional benefit.

scholarly journals Manufacturing, Characterisation and Mechanical Analysis of Polyacrylonitrile Membranes

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2378
Author(s):  
Mertol Tüfekci ◽  
Sevgi Güneş Durak ◽  
İnci Pir ◽  
Türkan Ormancı Acar ◽  
Güler Türkoğlu Demirkol ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Main Idea ◽  
Mechanical Analysis ◽  
Operating Conditions ◽  
Load Carrying Capacity ◽  
The Finite Element Method ◽  
Load Carrying ◽  
The Impact ◽  
Static Behaviour ◽  
Modelling Process

To investigate the effect of polyvinylpyrrolidone (PVP) addition and consequently porosity, two different sets of membranes are manufactured, since PVP is a widely used poring agent which has an impact on the mechanical properties of the membrane material. The first set (PAN 1) includes polyacrylonitrile (PAN) and the necessary solvent while the second set (PAN 2) is made of PAN and PVP. These membranes are put through several characterisation processes including tensile testing. The obtained data are used to model the static behaviour of the membranes with different geometries but similar loading and boundary conditions that represent their operating conditions. This modelling process is undertaken by using the finite element method. The main idea is to investigate how geometry affects the load-carrying capacity of the membranes. Alongside membrane modelling, their materials are modelled with representative elements with hexagonal and rectangular pore arrays (RE) to understand the impact of porosity on the mechanical properties. Exploring the results, the best geometry is found as the elliptic membrane with the aspect ratio 4 and the better RE as the hexagonal array which can predict the elastic properties with an approximate error of 12%.

scholarly journals A Flexible Load Control Strategy for Distribution Network to Reduce the Line Losses and to Eliminate the Transmission Congestion

2017 ◽  
Vol 2017 ◽  
pp. 1-16 ◽  
Author(s):  
Beibei Wang ◽  
Xiaoqing Hu ◽  
Peifeng Shen ◽  
Wenlu Ji ◽  
Yang Cao ◽  
...  
Keyword(s):  
Power Distribution ◽  
Distribution Systems ◽  
Renewable Energy Sources ◽  
Distribution Network ◽  
Test System ◽  
Operating Conditions ◽  
Load Control ◽  
Transmission Congestion ◽  
Heavy Load ◽  
Flexible Load

There are many uncertain factors in the modern distribution network, including the access of renewable energy sources and the heavy load level. The existence of these factors has brought challenges to the stability of the power distribution network, as well as increasing the risk of exceeding transmission capacity of distribution lines. The appearance of flexible load control technology provides a new idea to solve the above problems. Air conditioners (ACs) account for a great proportion of all loads. In this paper, the model of dispatching AC loads in the regional power grid is constructed, and the direct load control (DLC) method is adopted to reduce the load of ACs. An improved tabu search technique is proposed to solve the problem of network dispatch in distribution systems in order to reduce the resistive line losses and to eliminate the transmission congestion in lines under normal operating conditions. The optimal node solution is obtained to find the best location and reduction capacity of ACs for load control. To demonstrate the validity and effectiveness of the proposed method, a test system is studied. The numerical results are also given in this article, which reveal that the proposed method is promising.

Formation of a risk assessment model when selecting a foreign supplier under a foreign trade contract

2020 ◽  
Vol 26 (10) ◽  
pp. 82-87
Author(s):  
Lin Peng ◽  
Keyword(s):  
Supply Chain ◽  
Block Diagram ◽  
Operating Conditions ◽  
Assessment Model ◽  
Supply Chain Risk Management ◽  
Sources Of Information ◽  
Supply Chain Risk ◽  
Product Lines ◽  
Foreign Supplier ◽  
The Status

Many businesses that work with a large number of product lines face the problem of choosing a supplier of goods or services. The problem of finding suppliers is faced by most businesses that do business and are looking for new ways to optimize costs. Enterprises need to periodically search for suppliers, and this is much more difficult for them due to lack of experience, especially in relations with foreign suppliers. Procurement planning is carried out by selecting suppliers who must meet previously established criteria set by the company’s standards and legislation. The search and analysis of suppliers should be carried out systematically using all possible sources of information. At the present stage, conservative methods of searching, analyzing and selecting suppliers are being improved and supplemented with new forms and methods, but none of the existing methods of selecting a supplier properly takes into account the current operating conditions. Therefore, supply chain management is particularly relevant and requires improvement. The article suggests a model that allows identifying potentially unscrupulous suppliers even before the contract is executed in the supply chain and using management. The article presents a block diagram of the supply chain risk management model. The model specifies a key condition aimed at combining the work of all departments in order to increase the transparency of procedures. At the same time, the model will reduce the risks of the supply chain and improve the process of making logistics decisions within 3 main blocks. Information about the entire lifecycle of equipment, media, and items is stored in the supply chain information system, reflecting the status and attributes of all aspects and providing a variety of data support for decision - making

Detection and Ignoring of Blackhole Attack in Vanets Networks

2016 ◽  
Vol 6 (2) ◽  
pp. 1-10
Author(s):  
Chaima Bensaid ◽  
Sofiane Boukli Hacene ◽  
Kamel Mohamed Faraoun
Keyword(s):  
Black Hole ◽  
Communication Networks ◽  
Network Performance ◽  
Vehicular Networks ◽  
Data Communication ◽  
Main Idea ◽  
Black Hole Attack ◽  
Malicious Nodes ◽  
The Future ◽  
Detailed Simulation

Vehicular networks or VANET announce as the communication networks of the future, where the mobility is the main idea. These networks should be able to interconnect vehicles. The optimal goal is that these networks will contribute to safer roads and more effective in the future by providing timely information to drivers and concerned authorities. They are therefore vulnerable to many types of attacks among them the black hole attack. In this attack, a malicious node disseminates spurious replies for any route discovery in order to monopolize all data communication and deteriorate network performance. Many studies have focused on detecting and isolating malicious nodes in VANET. In this paper, the authors present two mechanisms to detect this attack. The main goal is detecting as well as bypass cooperative black hole attack. The authors' approaches have been evaluated by the detailed simulation study with NS2 and the simulation results shows an improvement of protocol performance.

Distribution Network Reconfiguration Using an Approximate Optimization Approach

2013 ◽  
Vol 303-306 ◽  
pp. 1276-1279
Author(s):  
Hai Na Rong ◽  
Yan Hui Qin
Keyword(s):  
Evolutionary Algorithm ◽  
Distribution Network ◽  
Operating Conditions ◽  
Distribution Automation ◽  
Optimization Approach ◽  
Network Reconfiguration ◽  
Power Network ◽  
Distribution Network Reconfiguration ◽  
Service Restoration ◽  
Integer Programming Problems

Power network reconfiguration is an important process in the improvement of operating conditions of a power system and in planning studies, service restoration and distribution automation when remote-controlled switches are employed. This paper presents the use of a quantum-inspired evolutionary algorithm to solve the distribution network reconfiguration problem. The quantum- inspired evolutionary algorithm is the combination product of quantum computing and evolutionary computation and is suitable for a class of integer programming problems such as the distribution network reconfiguration problem. After the analysis and formulation of the distribution network reconfiguration problem, the effectiveness and feasibility of the introduced method is verified by a large number of experiments.

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