Search results for: operation and preventive maintenance schedules
1111 A Low-cost Reconfigurable Architecture for AES Algorithm
Authors: Yibo Fan, Takeshi Ikenaga, Yukiyasu Tsunoo, Satoshi Goto
Abstract:
This paper proposes a low-cost reconfigurable architecture for AES algorithm. The proposed architecture separates SubBytes and MixColumns into two parallel data path, and supports different bit-width operation for this two data path. As a result, different number of S-box can be supported in this architecture. The throughput and power consumption can be adjusted by changing the number of S-box running in this design. Using the TSMC 0.18μm CMOS standard cell library, a very low-cost implementation of 7K Gates is obtained under 182MHz frequency. The maximum throughput is 360Mbps while using 4 S-Box simultaneously, and the minimum throughput is 114Mbps while only using 1 S-BoxKeywords: AES, Reconfigurable architecture, low cost
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20671110 Patient’s Knowledge and Use of Sublingual Glyceryl Trinitrate Therapy in Taiping Hospital, Malaysia
Authors: Wan Azuati Wan Omar, Selva Rani John Jasudass, Siti Rohaiza Md Saad
Abstract:
Background: The objectives of this study were to assess patient’s knowledge of appropriate sublingual glyceryl trinitrate (GTN) use as well as to investigate how patients commonly store and carry their sublingual GTN tablets. Methodology: This was a cross-sectional survey, using a validated researcher-administered questionnaire. The study involved cardiac patients receiving sublingual GTN attending the outpatient and inpatient departments of Taiping Hospital, a non-academic public care hospital. The minimum calculated sample size was 92, but 100 patients were conveniently sampled. Respondents were interviewed on 3 areas, including demographic data, knowledge and use of sublingual GTN. Eight items were used to calculate each subject’s knowledge score and six items were used to calculate use score. Results: Of the 96 patients who consented to participate, majority (96.9%) were well aware of the indication of sublingual GTN. With regards to the mechanism of action of sublingual GTN, 73 (76%) patients did not know how the medication works. Majority of the patients (66.7%) knew about the proper storage of the tablet. In relation to the maximum number of sublingual GTN tablets that can be taken during each angina episode, 36.5% did not know that up to 3 tablets of sublingual GTN can be taken during each episode of angina. Fifty four (56.2%) patients were not aware that they need to replace sublingual GTN every 8 weeks after receiving the tablets. Majority (69.8%) of the patients demonstrated lack of knowledge with regards to the use of sublingual GTN as prevention of chest pain. Conclusion: Overall, patients’ knowledge regarding the self-administration of sublingual GTN is still inadequate. The findings support the need for more frequent reinforcement of patient education, especially in the areas of preventive use, storage and drug stability.
Keywords: Glyceryl trinitrate, knowledge, adherence.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35041109 Role of Sequestration of CO2 Due to the Carbonation in Total CO2 Emission Balance in Concrete Life
Authors: P. P. Woyciechowski
Abstract:
Calculation of the carbon footprint of cement concrete is a complex process including consideration of the phase of primary life (components and concrete production processes, transportation, construction works, maintenance of concrete structures) and secondary life, including demolition and recycling. Taking into consideration the effect of concrete carbonation can lead to a reduction in the calculated carbon footprint of concrete. In this paper, an example of CO2 balance for small bridge elements made of Portland cement reinforced concrete was done. The results include the effect of carbonation of concrete in a structure and of concrete rubble after demolition. It was shown that important impact of carbonation on the balance is possible only when rubble carbonation is possible. It was related to the fact that only the sequestration potential in the secondary phase of concrete life has significant value.Keywords: Carbon footprint, balance of carbon dioxide in nature, concrete carbonation, the sequestration potential of concrete.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8321108 Remaining Useful Life Prediction Using Elliptical Basis Function Network and Markov Chain
Authors: Yi Yu, Lin Ma, Yong Sun, Yuantong Gu
Abstract:
This paper presents a novel method for remaining useful life prediction using the Elliptical Basis Function (EBF) network and a Markov chain. The EBF structure is trained by a modified Expectation-Maximization (EM) algorithm in order to take into account the missing covariate set. No explicit extrapolation is needed for internal covariates while a Markov chain is constructed to represent the evolution of external covariates in the study. The estimated external and the unknown internal covariates constitute an incomplete covariate set which are then used and analyzed by the EBF network to provide survival information of the asset. It is shown in the case study that the method slightly underestimates the remaining useful life of an asset which is a desirable result for early maintenance decision and resource planning.Keywords: Elliptical Basis Function Network, Markov Chain, Missing Covariates, Remaining Useful Life
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16621107 Software Obsolescence Drivers in Aerospace: An Industry Analysis
Authors: Raúl González Muñoz, Essam Shehab, Martin Weinitzke, Chris Fowler, Paul Baguley
Abstract:
Software applications have become crucial for the aerospace industry, providing a wide range of functionalities and capabilities. However, due to the considerable time difference between aircraft and software life cycles, obsolescence has turned into a major challenge for industry in last decades. This paper aims to provide a view on the different causes of software obsolescence within aerospace industry, as well as a perception on the importance of each of them. The key research question addressed is what drives software obsolescence in the aerospace industry, managing large software application portfolios. This question has been addressed by conducting firstly an in depth review of current literature and secondly by arranging an industry workshop with professionals from aerospace and consulting companies. The result is a set of drivers of software obsolescence, distributed among three different environments and several domains. By incorporating monitoring methodologies to assess those software obsolescence drivers, benefits in maintenance efforts and operations disruption avoidance are expected.Keywords: Aerospace industry, obsolescence drivers, software lifecycle, software obsolescence.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9421106 Conceptual Multidimensional Model
Authors: Manpreet Singh, Parvinder Singh, Suman
Abstract:
The data is available in abundance in any business organization. It includes the records for finance, maintenance, inventory, progress reports etc. As the time progresses, the data keep on accumulating and the challenge is to extract the information from this data bank. Knowledge discovery from these large and complex databases is the key problem of this era. Data mining and machine learning techniques are needed which can scale to the size of the problems and can be customized to the application of business. For the development of accurate and required information for particular problem, business analyst needs to develop multidimensional models which give the reliable information so that they can take right decision for particular problem. If the multidimensional model does not possess the advance features, the accuracy cannot be expected. The present work involves the development of a Multidimensional data model incorporating advance features. The criterion of computation is based on the data precision and to include slowly change time dimension. The final results are displayed in graphical form.Keywords: Multidimensional, data precision.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14581105 Investigating Causes of Pavement Deterioration in Khartoum State, Sudan
Authors: Magdi M. E. Zumrawi
Abstract:
It is quite essential to investigate the causes of pavement deterioration in order to select the proper maintenance technique. The objective of this study was to identify factors cause deterioration of recently constructed roads in Khartoum state. A comprehensive literature concerning the factors of road deterioration, common road defects and their causes were reviewed. Three major road projects with different deterioration reasons were selected for this study. The investigation involved field survey and laboratory testing on those projects to examine the existing pavement conditions. The results revealed that the roads investigated experienced severe failures in the forms of cracks, potholes, and rutting in the wheel path. The causes of those failures were found mainly linked to poor drainage, traffic overloading, expansive subgrade soils, and the use of low quality materials in construction. Based on the results, recommendations were provided to help highway engineers in selecting the most effective repair techniques for specific kinds of distresses.Keywords: Pavement, deterioration, causes, failures.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 49761104 Drought Resilient Water Supply: Establishment of Groundwater Treatment Plant at Construction Sites in Taichung City
Authors: Shang-Hsin Ou, Yang-Chun Lin, Ke-Hao Cheng
Abstract:
The year 2021 marked a historic drought in Taiwan, posing unprecedented challenges due to record-low rainfall and inadequate reservoir storage. The central region experienced water scarcity, leading to the implementation of "Groundwater Utilization at Construction Sites" for drought-resilient livelihood water supply. This study focuses on the establishment process of temporary groundwater treatment plants at construction sites in Taichung City, serving as a reference for future emergency response and the utilization of construction site groundwater. To identify suitable sites for groundwater reuse projects, site selection operations were carried out based on relevant water quality regulations and assessment principles. Subsequently, the planning and design of temporary water treatment plants were conducted, considering the water quality, quantity, and on-site conditions of groundwater wells associated with construction projects. The study consolidates the major water treatment facilities at each site and addresses encountered challenges during the establishment process. Practical insights gained from operating temporary groundwater treatment plants are presented, including improvements related to stable water quality, water quantity, equipment operation, and hydraulic control. In light of possible future droughts, this study provides an outlook and recommendations to expedite and improve the setup of groundwater treatment plants at construction sites. This includes considering on-site water abstraction, treatment, and distribution conditions. The study aims to provide concise guidelines for setting up and managing temporary groundwater treatment plants at construction sites, drawing insights from Taichung City's establishment process. It offers recommendations for addressing challenges like water quality, quantity, equipment operation, and regulation compliance. By sharing these insights, it aims to aid regions facing similar emergencies, ensuring sustainable water supply and societal stability amidst water shortages and droughts.
Keywords: Drought resilience, groundwater treatment, construction site, water supply.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 711103 Evaluation of Risk Attributes Driven by Periodically Changing System Functionality
Authors: Dariusz Dymek, Leszek Kotulski
Abstract:
Modeling of the distributed systems allows us to represent the whole its functionality. The working system instance rarely fulfils the whole functionality represented by model; usually some parts of this functionality should be accessible periodically. The reporting system based on the Data Warehouse concept seams to be an intuitive example of the system that some of its functionality is required only from time to time. Analyzing an enterprise risk associated with the periodical change of the system functionality, we should consider not only the inaccessibility of the components (object) but also their functions (methods), and the impact of such a situation on the system functionality from the business point of view. In the paper we suggest that the risk attributes should be estimated from risk attributes specified at the requirements level (Use Case in the UML model) on the base of the information about the structure of the model (presented at other levels of the UML model). We argue that it is desirable to consider the influence of periodical changes in requirements on the enterprise risk estimation. Finally, the proposition of such a solution basing on the UML system model is presented.Keywords: Risk assessing, software maintenance, UML, graph grammars.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13851102 Development and Analysis of a Machine to Equally Apply Mineral Fertilizer to Soil on Slopes
Authors: Qurbanov Huseyn Nuraddin
Abstract:
Reliable food supply of the population of a country is one of the main directions of the state's economic policy. Grain growing, which is the basis of agriculture, is important in this area. In the cultivation of cereals on slopes, the application of equal amounts of mineral fertilizers to under the soil before sowing is a very important technological process. The low level of technical equipment in this area prevents producers from providing the country with the necessary quality cereals. Experience in the operation of modern technical means has shown that at present, there is a need to provide an equal amount of fertilizer to under the soil on slopes, fully meeting the agro-technical requirements. No fundamental changes have been made to the industrial machines that fertilize under the soil, and unequal application of fertilizers to under the soil on slopes has been applied. This technological process leads to the destruction of new seedlings and reduced productivity due to intolerance to frost during the winter for the plant planted in the fall. In special climatic conditions, there is an optimal fertilization rate for each agricultural product. The application of fertilizers to the soil is one of the conditions that increase their efficiency in the field. As can be seen, the development of a new technical proposal for fertilizing and plowing the slopes in equal amounts on the slopes, improving the technological and design parameters, taking into account the physical and mechanical properties of fertilizers, is very important. Taking into account the above-mentioned issues, a combined plough was developed in our laboratory. Combined plough carries out pre-sowing technological operation in the cultivation of cereals, providing a smooth equal amount of mineral fertilizers to under the soil on the slopes. Mathematical models of a smooth spreader that evenly distributes fertilizers in the field have been developed. Thus, diagrams and graphs obtained without distribution on the eight partitions of the smooth spreader are constructed under the inclined angles of the slopes. Percentage and productivity of equal distribution in the field were noted by practical and theoretical analysis.
Keywords: Combined plough, mineral fertilizer, equal sowing, fertilizer norm, grain-crops, sowing fertilizer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3891101 A Research on DC Voltage Offsets Generated by PWM-Controlled Inverters
Authors: Marios N. Moschakis
Abstract:
The increasing penetration of Distributed Generation and storage connected to the distribution network via PWM converters increases the possibility of a DC-component (offset) in voltage or current flowing into the grid. This occurs when even harmonics are present in the network voltage. DC-components can affect the operation and safety of several grid components. Therefore, an investigation of the way they are produced is important in order to take appropriate measures for their elimination. Further research on DC-components that appear on output voltage of converters is performed for different parameters of PWM technique and characteristics of even harmonics.
Keywords: Asymmetric even harmonics, DC-offsets, distributed generation, electric machine drive systems, power quality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 36851100 Improvement of Realization Quality of Aerospace Products Using Augmented Reality Technology
Authors: Nuran Bahar, Mehmet A. Akcayol
Abstract:
In the aviation industry, many faults may occur frequently during the maintenance processes and assembly operations of complex structured aircrafts because of their high dependencies of components. These faults affect the quality of aircraft parts or developed modules adversely. Technical employee requires long time and high labor force while checking the correctness of each component. In addition, the person must be trained regularly because of the ever-growing and changing technology. Generally, the cost of this training is very high. Augmented Reality (AR) technology reduces the cost of training radically and improves the effectiveness of the training. In this study, the usage of AR technology in the aviation industry has been investigated and the effectiveness of AR with heads-up display glasses has been examined. An application has been developed for comparison of production process with AR and manual one.
Keywords: Aerospace, assembly quality, augmented reality, heads-up display.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17441099 Current Drainage Attack Correction via Adjusting the Attacking Saw Function Asymmetry
Authors: Yuri Boiko, Iluju Kiringa, Tet Yeap
Abstract:
Current drainage attack suggested previously is further studied in regular settings of closed-loop controlled Brushless DC (BLDC) motor with Kalman filter in the feedback loop. Modeling and simulation experiments are conducted in a MATLAB environment, implementing the closed-loop control model of BLDC motor operation in position sensorless mode under Kalman filter drive. The current increase in the motor windings is caused by the controller (p-controller in our case) affected by false data injection of substitution of the angular velocity estimates with distorted values. Operation of multiplication to distortion coefficient, values of which are taken from the distortion function synchronized in its periodicity with the rotor’s position change. A saw function with a triangular tooth shape is studied herewith for the purpose of carrying out the bias injection with current drainage consequences. The specific focus here is on how the asymmetry of the tooth in the saw function affects the flow of current drainage. The purpose is two-fold: (i) to produce and collect the signature of an asymmetric saw in the attack for further pattern recognition process, and (ii) to determine conditions of improving stealthiness of such attack via regulating asymmetry in saw function used. It is found that modification of the symmetry in the saw tooth affects the periodicity of current drainage modulation. Specifically, the modulation frequency of the drained current for a fully asymmetric tooth shape coincides with the saw function modulation frequency itself. Increasing the symmetry parameter for the triangle tooth shape leads to an increase in the modulation frequency for the drained current. Moreover, such frequency reaches the switching frequency of the motor windings for fully symmetric triangular shapes, thus becoming undetectable and improving the stealthiness of the attack. Therefore, the collected signatures of the attack can serve for attack parameter identification via the pattern recognition route.
Keywords: Bias injection attack, Kalman filter, BLDC motor, control system, closed loop, P-controller, PID-controller, current drainage, saw-function, asymmetry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1551098 Flexible Manufacturing System
Authors: Peter Kostal, Karol Velisek
Abstract:
Flexible manufacturing system is a system that is able to respond to changed conditions. In general, this flexibility is divided into two key categories and several subcategories. The first category is the so called machine flexibility which enables to make various products by the given machinery. The second category is routing flexibility enabling to execute the same operation by various machines. Flexible manufacturing systems usually consist of three main parts: CNC machine tools, transport system and control system. A higher level of flexible manufacturing systems is represented by the so called intelligent manufacturing systems.
Keywords: drawing-free manufacturing, flexible manufacturing system, industrial robot, material flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 49591097 Feature Weighting and Selection - A Novel Genetic Evolutionary Approach
Authors: Serkawt Khola
Abstract:
A feature weighting and selection method is proposed which uses the structure of a weightless neuron and exploits the principles that govern the operation of Genetic Algorithms and Evolution. Features are coded onto chromosomes in a novel way which allows weighting information regarding the features to be directly inferred from the gene values. The proposed method is significant in that it addresses several problems concerned with algorithms for feature selection and weighting as well as providing significant advantages such as speed, simplicity and suitability for real-time systems.Keywords: Feature weighting, genetic algorithm, pattern recognition, weightless neuron.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18551096 A Review on Marine Search and Rescue Operations Using Unmanned Aerial Vehicles
Authors: S. P. Yeong, L. M. King, S. S. Dol
Abstract:
There have been rigorous research and development of unmanned aerial vehicles in the field of search and rescue (SAR) operation recently. UAVs reduce unnecessary human risks while assisting rescue efforts through aerial imagery, topographic mapping and emergency delivery. The application of UAVs in offshore and nearshore marine SAR missions is discussed in this paper. Projects that integrate UAV technology into their systems are introduced to highlight the great advantages and capabilities of UAVs. Scenarios where UAVs could provide invaluable assistance are also suggested.Keywords: Marine SAR, nearshore, offshore, search and rescue, UAS, UAV.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 55331095 Evaluating Psychologist Practice Competencies through Multisource Feedback: An International Research Design
Authors: Jac W. Andrews, J. B. Hale
Abstract:
Effective practicing psychologists require ongoing skill development that is constructivist and recursive in nature, with mentor, colleague, co-worker, and patient feedback critical to successful acquisition and maintenance of professional competencies. This paper will provide an overview of the nature and scope of psychologist skill development through multisource feedback (MSF) or 360 degree evaluation, present a rationale for its use for assessing practicing psychologist performance, and advocate its use in psychology given the demonstrated model utility in other health professions. The paper will conclude that an international research design is needed to assess the feasibility, reliability, and validity of MSF system ratings intended to solicit feedback from mentors, colleagues, coworkers, and patients about psychologist competencies. If adopted, the MSF model could lead to enhanced skill development that fosters patient satisfaction within and across countries.
Keywords: Psychologist, multisource feedback, psychologist competency, professionalism.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22281094 Validation of Solar PV Inverter Harmonics Behaviour at Different Power Levels in a Test Network
Authors: Wilfred Fritz
Abstract:
Grid connected solar PV inverters need to be compliant to standard regulations regarding unwanted harmonic generation. This paper gives an introduction to harmonics, solar PV inverter voltage regulation and balancing through compensation and investigates the behaviour of harmonic generation at different power levels. Practical measurements of harmonics and power levels with a power quality data logger were made, on a test network at a university in Germany. The test setup and test results are discussed. The major finding was that between the morning and afternoon load peak windows when the PV inverters operate under low solar insolation and low power levels, more unwanted harmonics are generated. This has a huge impact on the power quality of the grid as well as capital and maintenance costs. The design of a single-tuned harmonic filter towards harmonic mitigation is presented.
Keywords: Harmonics, power quality, pulse width modulation, total harmonic distortion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18431093 Requirements Engineering for Enterprise Applications Development: Seven Challenges in Higher Education Environment
Authors: Jamaludin Sallim
Abstract:
This paper describes the challenges on the requirements engineering for developing an enterprise applications in higher education environment. The development activities include software implementation, maintenance, and enhancement and support for online transaction processing and overnight batch processing. Generally, an enterprise application for higher education environment may include Student Information System (SIS), HR/Payroll system, Financial Systems etc. By the way, there are so many challenges in requirement engineering phases in order to provide two distinctive services that are production processing support and systems development.Keywords: enterprise applications development, enterprise information systems, business process, requirement engineering, requirement standards, software development activities, software requirement reviews.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17191092 Analysis of Surface Spalling on a First Intermediate Roll in Sendzirmir Mills
Authors: Shiang-Cheng Jeng, Horng-Shing Chiou
Abstract:
A first intermediate roll of Sendzirmir mills was failure by surface spalling during operation. After analyzing by visual, stereo microscope, optical microscope, scanning electron microscope, glow-discharged spectrometer and hardness test, respectively, the results show that some voids and cracks existed on the contact surface as well as subsurface. Further examination verified inadequate hardness and inclusions were responsible for the failure of surface spalling.Keywords: Sendzirmir mills; surface spalling; fatigue failure;inclusion; contact stress
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22931091 Fuzzy Shortest Paths Approximation for Solving the Fuzzy Steiner Tree Problem in Graphs
Authors: Miloš Šeda
Abstract:
In this paper, we deal with the Steiner tree problem (STP) on a graph in which a fuzzy number, instead of a real number, is assigned to each edge. We propose a modification of the shortest paths approximation based on the fuzzy shortest paths (FSP) evaluations. Since a fuzzy min operation using the extension principle leads to nondominated solutions, we propose another approach to solving the FSP using Cheng's centroid point fuzzy ranking method.Keywords: Steiner tree, single shortest path problem, fuzzyranking, binary heap, priority queue.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16951090 Technique for Online Condition Monitoring of Surge Arrestors
Authors: Anil S. Khopkar, Kartik S. Pandya
Abstract:
Lightning overvoltage phenomenon in power systems cannot be avoided; however, it can be controlled to certain extent. To prevent system failure, power system equipment must be protected against overvoltage. Metal Oxide Surge Arrestors (MOSA) are connected in the system to provide protection against overvoltages. Under normal working conditions, MOSA function as, insulators, offering a conductive path during overvoltage events. MOSA consists of zinc oxide elements (ZnO Blocks) which has non-linear V-I characteristics. The ZnO blocks are connected in series and fitted in ceramic or polymer housing. Over time, these components degrade due to continuous operation. The degradation of zinc oxide elements increases the leakage current flowing through the surge arrestors. This increased leakage current results in elevated temperatures within the surge arrester, further decreasing the resistance of the zinc oxide elements. Consequently, the leakage current increases, leading to higher temperatures within the MOSA. This cycle creates thermal runaway conditions for the MOSA. Once a surge arrester reaches the thermal runaway condition, it cannot return to normal working conditions. This condition is a primary cause of premature failure of surge arrestors. Given that MOSA constitutes a core protective device for electrical power systems against transients, it contributes significantly to the reliable operation of power system networks. Therefore, periodic condition monitoring of surge arrestors is essential. Both online and offline condition monitoring techniques are available for surge arrestors. Offline condition monitoring techniques are not as popular because they require the removal of surge arrestors from the system, which requires system shutdown. Therefore, online condition monitoring techniques are more commonly used. This paper presents an evaluation technique for the surge arrester condition based on leakage current analysis. The maximum amplitudes of total leakage current (IT), fundamental resistive leakage current (IR), and third harmonic resistive leakage current (I3rd) are analyzed as indicators for surge arrester condition monitoring.
Keywords: Metal Oxide Surge Arrester, MOSA, Over voltage, total leakage current, resistive leakage current, third harmonic resistive leakage current, capacitive leakage current.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 851089 Using Combination of Optimized Recurrent Neural Network with Design of Experiments and Regression for Control Chart Forecasting
Authors: R. Behmanesh, I. Rahimi
Abstract:
recurrent neural network (RNN) is an efficient tool for modeling production control process as well as modeling services. In this paper one RNN was combined with regression model and were employed in order to be checked whether the obtained data by the model in comparison with actual data, are valid for variable process control chart. Therefore, one maintenance process in workshop of Esfahan Oil Refining Co. (EORC) was taken for illustration of models. First, the regression was made for predicting the response time of process based upon determined factors, and then the error between actual and predicted response time as output and also the same factors as input were used in RNN. Finally, according to predicted data from combined model, it is scrutinized for test values in statistical process control whether forecasting efficiency is acceptable. Meanwhile, in training process of RNN, design of experiments was set so as to optimize the RNN.Keywords: RNN, DOE, regression, control chart.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16591088 Theoretical Study on a Thermal Model for Large Power Transformer Units
Authors: Traian Chiulan, Brandusa Pantelimon
Abstract:
The paper analyzes the large power transformer unit regimes, indicating the criteria for the management of the voltage operating conditions, as well as the change in the operating conditions with the load connected to the secondary winding of the transformer unit. Further, the paper presents the software application for the evaluation of the transformer unit operation under different conditions. The software application was developed by means of virtual instrumentation.
Keywords: Operating regimes, power transformer, overload, lifetime, virtual instrumentation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16391087 Structural Rehabilitation, Retrofitting and Strengthening of Reinforced Concrete Structures
Authors: Manish Kumar
Abstract:
Reinforced cement concrete is getting extensively used for construction of different type of structures for the last one century. During this period, we have constructed many structures like buildings, bridges, industrial structures, pavement, water tanks etc. using this construction material. These structures have been created with huge investment of resources. It is essential to maintain those structures in functional condition. Since deterioration in RCC Structures is a common and natural phenomenon it is required to have a detailed plan, methodology for structural repair and rehabilitation shall be in place for dealing such issues. It is important to know exact reason of distress, type of distress and correct method of repair concrete structures. The different methods of repair are described in paper according to distress category which can be refereed for repair. Major finding of the study is that to protect our structure we need to have maintenance frequency and correct material to be chosen for repair. Also workmanship during repair needs to be taken utmost care for quality repair.Keywords: Deterioration, functional condition, reinforced cement concrete, resources.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 46951086 Self-Tuning Power System Stabilizer Based on Recursive Least Square Identification and Linear Quadratic Regulator
Authors: J. Ritonja
Abstract:
Available commercial applications of power system stabilizers assure optimal damping of synchronous generator’s oscillations only in a small part of operating range. Parameters of the power system stabilizer are usually tuned for the selected operating point. Extensive variations of the synchronous generator’s operation result in changed dynamic characteristics. This is the reason that the power system stabilizer tuned for the nominal operating point does not satisfy preferred damping in the overall operation area. The small-signal stability and the transient stability of the synchronous generators have represented an attractive problem for testing different concepts of the modern control theory. Of all the methods, the adaptive control has proved to be the most suitable for the design of the power system stabilizers. The adaptive control has been used in order to assure the optimal damping through the entire synchronous generator’s operating range. The use of the adaptive control is possible because the loading variations and consequently the variations of the synchronous generator’s dynamic characteristics are, in most cases, essentially slower than the adaptation mechanism. The paper shows the development and the application of the self-tuning power system stabilizer based on recursive least square identification method and linear quadratic regulator. Identification method is used to calculate the parameters of the Heffron-Phillips model of the synchronous generator. On the basis of the calculated parameters of the synchronous generator’s mathematical model, the synthesis of the linear quadratic regulator is carried-out. The identification and the synthesis are implemented on-line. In this way, the self-tuning power system stabilizer adapts to the different operating conditions. A purpose of this paper is to contribute to development of the more effective power system stabilizers, which would replace currently used linear stabilizers. The presented self-tuning power system stabilizer makes the tuning of the controller parameters easier and assures damping improvement in the complete operating range. The results of simulations and experiments show essential improvement of the synchronous generator’s damping and power system stability.
Keywords: Adaptive control, linear quadratic regulator, power system stabilizer, recursive least square identification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11231085 Neuro-Fuzzy System for Equalization Channel Distortion
Authors: Rahib H. Abiyev
Abstract:
In this paper the application of neuro-fuzzy system for equalization of channel distortion is considered. The structure and operation algorithm of neuro-fuzzy equalizer are described. The use of neuro-fuzzy equalizer in digital signal transmission allows to decrease training time of parameters and decrease the complexity of the network. The simulation of neuro-fuzzy equalizer is performed. The obtained result satisfies the efficiency of application of neurofuzzy technology in channel equalization.
Keywords: Neuro-fuzzy system, noise equalization, neuro-fuzzy equalizer, neural system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16321084 Centralized Controller for Microgrid
Authors: Adel Hamad Rafa
Abstract:
This paper, proposes a control system for use with microgrid consiste of multiple small scale embedded generation networks (SSEG networks) connected to the 33kV distribution network. The proposed controller controls power flow in the grid-connected mode of operation, enables voltage and frequency control when the SSEG networks are islanded, and resynchronises the SSEG networks with the utility before reconnecting them. The performance of the proposed controller has been tested in simulations using PSCAD.
Keywords: Microgrid, Small scale embedded generation, island mode, resynchronisation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20311083 Photovoltaic Small-Scale Wastewater Treatment Project for Rural and New-Cultivated Areas in Egypt
Authors: Fadia M. A. Ghali
Abstract:
The problem of wastewater treatment in Egypt is a two-fold problem; the first part concerning the existing rural areas, the second one dealing with new industrial/domestic areas. In Egypt several agricultural projects have been initiated by the government and the private sector as well, in order to change its infrastructure. As a reliable energy source, photovoltaic pumping systems have contributed to supply water for local rural communities worldwide; they can also be implemented to solve the problem “wastewater environment pollution". The solution of this problem can be categorised as recycle process. In addition, because of regional conditions past technologies are being reexamined to select a smallscale treatment system requiring low construction and maintenance costs. This paper gives the design guidelines of a Photovoltaic Small- Scale Wastewater Treatment Plant (PVSSWTP) based on technologies that can be transferred.
Keywords: Renewable energy sources, Photovoltaic, small-scale projects, wastewater treatment.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26021082 A Fuzzy Implementation for Optimization of Storage Locations in an Industrial AS/RS
Authors: C. Senanayake, S. Veera Ragavan
Abstract:
Warehousing is commonly used in factories for the storage of products until delivery of orders. As the amount of products stored increases it becomes tedious to be carried out manually. In recent years, the manual storing has converted into fully or partially computer controlled systems, also known as Automated Storage and Retrieval Systems (AS/RS). This paper discusses an ASRS system, which was designed such that the best storage location for the products is determined by utilizing a fuzzy control system. The design maintains the records of the products to be/already in store and the storage/retrieval times along with the availability status of the storage locations. This paper discusses on the maintenance of the above mentioned records and the utilization of the concept of fuzzy logic in order to determine the optimum storage location for the products. The paper will further discuss on the dynamic splitting and merging of the storage locations depending on the product sizes.Keywords: ASRS, fuzzy control systems, MySQL database, dynamic splitting and merging.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2142