12,415 research outputs found
Evaluation of Time-Critical Communications for IEC 61850-Substation Network Architecture
Present-day developments, in electrical power transmission and distribution,
require considerations of the status quo. In other meaning, international
regulations enforce increasing of reliability and reducing of environment
impact, correspondingly they motivate developing of dependable systems. Power
grids especially intelligent (smart grids) ones become industrial solutions
that follow standardized development. The International standardization, in the
field of power transmission and distribution, improve technology influences.
The rise of dedicated standards for SAS (Substation Automation Systems)
communications, such as the leading International Electro-technical Commission
standard IEC 61850, enforces modern technological trends in this field. Within
this standard, a constraint of low ETE (End-to-End) latency should be
respected, and time-critical status transmission must be achieved. This
experimental study emphasis on IEC 61850 SAS communication standard, e.g. IEC
61850 GOOSE (Generic Object Oriented Substation Events), to implement an
investigational method to determine the protection communication delay. This
method observes GOOSE behaviour by adopting monitoring and analysis
capabilities. It is observed by using network test equipment, i.e. SPAN (Switch
Port Analyser) and TAP (Test Access Point) devices, with on-the-shelf available
hardware and software solutions
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Update of an early warning fault detection method using artificial intelligence techniques
This presentation describes a research investigation to access the feasibility of using an Artificial Intelligence (AI) method to predict and detect faults at an early stage in power systems. An AI based detector has been developed to monitor and predict faults at an early stage on particular sections of power systems. The detector for this early warning fault detection device only requires external measurements taken from the input and output nodes of the power system. The AI detection system is capable of rapidly predicting a malfunction within the system. Artificial Neural Networks (ANNs) are being used as the core of the fault detector. In an earlier paper [11], a computer simulated medium length transmission line has been tested by the detector and the results clearly demonstrate the capability of the detector. Today’s presentation considers a case study illustrating the suitability of this AI Technique when applied to a distribution transformer. Furthermore, an evolutionary optimisation strategy to train ANNs is also briefly discussed in this presentation, together with a ‘crystal ball’ view of future developments in the operation and monitoring of transmission systems in the next millennium
Evolvable Hardware Based Optimal Position Control of Quadcopter
Trading off performance metrics in control design for position tracking is unavoidable. This has severe consequences in mission-critical systems such as quadcopter applications. The controller area and propulsion energy are conflicting design parameters, whereas the reliability and tracking speed are related metrics to be optimized. In this research, a switching-based position controller was co-simulated with the quadcopter model. Performance analysis of the Field Programmable Gate Array (FPGA)-based controller validates a better scheme for tracking speed, propulsion energy, and reliability optimization under similar error performance. To improve the computation power and controller area, the dynamic partial reconfiguration(DPR) approach has been adapted and implemented on FPGA using the Vivado Integrated Development Environment (IDE), where a ranking-based approach brings into action either proportional derivative, sliding mode, or model predictive controllers for each dimension of position tracking. It is verified by analyzing the cumulative tracking speed, reliability, controller area, and propulsion energy metrics that the proposed controller can optimize all these metrics within three successive iterations of tracking either in the same direction or in any combination of directions. Concerning the implementation results of the controller with the switching-based controller, there is 6 % computation power and 30 % resource savings due to DPR
Automatic programming methodologies for electronic hardware fault monitoring
This paper presents three variants of Genetic Programming (GP) approaches for intelligent online performance monitoring of electronic circuits and systems. Reliability modeling of electronic circuits can be best performed by the Stressor - susceptibility interaction model. A circuit or a system is considered to be failed once the stressor has exceeded the susceptibility limits. For on-line prediction, validated stressor vectors may be obtained by direct measurements or sensors, which after pre-processing and standardization are fed into the GP models. Empirical results are compared with artificial neural networks trained using backpropagation algorithm and classification and regression trees. The performance of the proposed method is evaluated by comparing the experiment results with the actual failure model values. The developed model reveals that GP could play an important role for future fault monitoring systems.This research was supported by the International Joint Research Grant of the IITA (Institute of Information Technology Assessment) foreign professor invitation program of the MIC (Ministry of Information and Communication), Korea
Comparison of rhombic type micromixer to improve mixing efficiency in biomems application.
The term lab on chip and micro total analysis system stand synonymous for devices that require handling and processing of small amount of fluid to perform function such as sample preparation, separation, biosensing and detection. Constraint
to the long mixing channel and miniaturized in size but efficiently mixed between fluids. In this project, the three types of rhombic geometry design were studied to characterize mixing performance between the blood sample and reagents. Pure rhombic, branch rhombic and slanted groove rhombic glass based micromixer were proposed to study the mixing performance. The simulation was obtained using CoventorWare 2010. The laminar mixing between blood sample and reagent was simulated at low Reynolds number flow (Re <<1). Reagents used are toluene-low viscosity reagent and carbolic acid- higher viscosity reagent in comparison to blood.
mixing characterization will be optimized based on visualization result of the distribution field in term of viscosity. Image standard deviation (σ) is used to characterize fluid mixing; the lower σ, the better in fluids mixing properties. From
study, it was found that slanted groove rhombic gained the highest mixing efficiency followed by pure rhombic and branch rhombic. This is because grooves structure can improve surface contact area thus stretch and folds the laminar flows
Factors shaping the evolution of electronic documentation systems
The main goal is to prepare the space station technical and managerial structure for likely changes in the creation, capture, transfer, and utilization of knowledge. By anticipating advances, the design of Space Station Project (SSP) information systems can be tailored to facilitate a progression of increasingly sophisticated strategies as the space station evolves. Future generations of advanced information systems will use increases in power to deliver environmentally meaningful, contextually targeted, interconnected data (knowledge). The concept of a Knowledge Base Management System is emerging when the problem is focused on how information systems can perform such a conversion of raw data. Such a system would include traditional management functions for large space databases. Added artificial intelligence features might encompass co-existing knowledge representation schemes; effective control structures for deductive, plausible, and inductive reasoning; means for knowledge acquisition, refinement, and validation; explanation facilities; and dynamic human intervention. The major areas covered include: alternative knowledge representation approaches; advanced user interface capabilities; computer-supported cooperative work; the evolution of information system hardware; standardization, compatibility, and connectivity; and organizational impacts of information intensive environments
Delay measurements In live 5G cellular network
Abstract. 5G Network has many important properties, including increased bandwidth, increased data throughput, high reliability, high network density, and low latency. This thesis concentrate on the low latency attribute of the 5G Standalone (SA) mode and 5G Non-Standalone (NSA) mode.
One of the most critical considerations in 5G is to have low latency network for various delay-sensitive applications, such as remote diagnostics and surgery in healthcare, self-driven cars, industrial factory automation, and live audio productions in the music industry. Therefore, 5G employs various retransmission algorithms and techniques to meet the low latency standards, a new frame structure with multiple subcarrier spacing (SCS) and time slots, and a new cloud-native core.
For the low latency measurements, a test setup is built. A video is sent from the 5G User Equipment (UE) to the multimedia server deployed in the University of Oulu 5G test Network (5GTN) edge server. The University of Oulu 5GTN is operating both in NSA and SA modes. Delay is measured both for the downlink and the uplink direction with Qosium tool. When calculating millisecond-level transmission delays, clock synchronization is essential. Therefore, Precision Time Protocol daemon (PTPd) service is initiated on both the sending and receiving machines.
The tests comply with the specifications developed at the University of Oulu 5GTN for both the SA and the NSA mode. When the delay measurement findings were compared between the two deployment modes, it was observed that the comparison was not appropriate. The primary reason for this is that in the 5GTN, the NSA and the SA have entirely different data routing paths and configurations. Additionally, the author did not have sufficient resources to make the required architectural changes
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