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A Unique Approach to Solve the System of Linear Equations
No full textSystem of linear equations is a set of linear equations with same types of variables. Aside from mathematics, systems of linear equations are used in information theory, communication theory, and related fields. This study is aimed at analyzing the available methods and develops a new solution which does not involve direct matrix inversion for system of linear equations. By comparing the different test results with an existing and very well-known method called gauss elimination method, it has been seen that in terms of numerical accuracy and computing time the proposed approach achieves improve results. Furthermore, even very large systems can be solved by this proposed algorithm given a cluster with sufficient resources
On the Behavior of Five-Phase Induction Motor Drive Under Normal and Faulty Conditions
No full textThis paper describes the importance and applications of multi-phase electrical machines. The components of the five-phase electrical drive were analyzed. Due to the MATLAB/Simulink model, the simulation of the electrical drive under normal mode and faulty conditions was carried out to analyze the performance of the five-phase induction motor. Several cases of faulty conditions caused by unbalanced voltage system were considered and the simulation results of stator phase’s currents, rotor speed and electromagnetic torque were analyzed in more detail. The importance of this study is related to the various applications of multi-phase machines in different fields of industry and a lot of scientific researches based on this topic. Simulation results have shown that the five-phase machine is very reliable and it has better fault tolerance due to its slightly affected by the unbalanced voltage system
The Power of Six Sigma Tool for Defect Reduction: Real Case from the Industrial Sector in Saudi Arabia
No full textAchieving the highest levels of quality is the main target for all companies in all sectors. The aspect of the highest quality differs from organization to another. It could mean exceeding customers` expectations, speed of delivery, feasibility, product quality, reduce total cost, or minimizing the total defects in processes/services. Six Sigma is practical work to get error-free business performance. One of the Six Sigma’s distinctive approaches to process and quality improvement is DAMIC (define, measure, analyze, improve and control). DAMIC model refers to five interconnected stages that systematically help organizations to solve problems and improve their processes. This work illustrated applying DAMIC model in the industrial sector. The data of this case obtained from a leading manufacturing company based on Jeddah, Kingdom of Saudi Arabia. Statistical analysis has been applied using EViews7 and SPSS25. A Cause-and- Effect diagram has been proposed. Whereas correction and improvement actions have been suggested by the quality team of the company
Numerical Study of Reinforced Concrete Beam by Using ABAQUS Software
No full textCracks are serious problems in the structural characteristics of a concrete structure due to several failure modes such as, flexural and shear. Reinforced concrete behaviour is complicated, and for a realistic simulation of such behaviour a prober material modelling has to be used. In this work an attempt has been made to simulate concrete and embedded reinforcement steel to predict the crack propagation in RC beam using a plastic damage behaviour by ABAQUS software. The proposed modelling has been validated against experimental results found in the literature. The results have shown that displacement associated with ultimate load is in a good agreement with experiment, as well as the failure load. The crack pattern indicated that the cracks will start from the tension zone in the bottom of RC beam and extended to top of beam
Coseismic ground deformation of the November 26, 2019 M6.4 earthquake of Durrës, Albania estimated by DInSAR
No full textAn earthquake of magnitude 6.4 occurred in Albania on November 26, 2019 at 03:54:12 (local time). The epicenter of the earthquake was about 20 km from the coastal city of Durrës. The earthquake caused severe damage. In order to estimate the ground deformation associated with the earthquake, a pair of Sentinel-1 radar images was analysed by Differential Interferometric Synthetic Aperture Radar (DInSAR) technique. A differential interferogram was formed using the two Sentinel-1 Single Look Complex (SLC) images. The flattened and filtered differential interferogram was unwrapped and converted to ground displacement. The results show that in the area of the epicenter the ground is uplifted at a maximum of 8 cm along the radar line-of-sight (LOS). The earthquake could be related with under thrusting of Adria microplate or fault processes within the under thrusted Adria microplate itself. Further monitoring by satellite imagery is needed to investigate the post-seismic ground deformation in the area
Analytical Study on the Influence of Rib Beams on the Stability of RCC Dome Structures
No full textDome systems are space structures which cover a big area with minimum support. It is a doubly curved shell structure. Dome is stronger, stable and sturdy than any other singly curved shell structures which are relevant to many civil engineering structures like an auditorium, exhibition hall, industrial structures, pinnacle protection of ground water tank etc. Modern concrete shell domes can be constructed to the ratio (thickness-toradius) of 1:800, using concrete and wire mesh and they are safe, aesthetically pleasing and long-lasting. The main aim of this study is to analyze the behaviour and strength of modern-day thin spherical shell domes made of concrete with and without rib beams using finite element technique with the help of SAP2000 software. The work consists of the erection of round domes with a massive diameter of 50m, 100m, and 150m with and without rib beams and a shell thickness of 15cm. Analytical study on all models was performed to study the influence of the big diameter and thickness of shell dome on stress distribution
Power system analysis: The case of Albania
No full textClimate change, sustainability and supply security are today priority themes worldwide. This paper presents the results of an Albanian power system analysis. An energy system analysis model based on linear programming is used for modelling and optimization. The analyses cover a number of scenarios where the studied system is subjected to changes by introducing other renewable energy sources, energy conservation measures and measures to promote renewable energy. The study shows that because of a combination of cheap hydropower, low electricity prices and rather high investment costs, it is very hard for new non-hydro renewable energy sources to be profitable with the prevailing market condition. Regional power exchange based on bilateral agreement in some way or another encourage dependency on import instead of facilitating the introduction of new renewable energy sources. On the other hand, solar wind power could be viable if market-based power prices or other policy measures are introduced to promote the use of solar and wind power
The Influence of Cavitations Phenomenon and Water Hammer in Batlava Pumping Station
No full textCavitations’ phenomenon and water hammer fall in group of critical characteristics of turbo machinery and are a pernicious phenomenon that may occur during their exploitation. Water hammer appears in case when pressures change as a result of rapidly changing water flow velocity. As a preventive measure by water hammer is slowdown of the flow velocity of the water and all recommendations based on this purpose are categorized into: slowdown water flow velocity, protection from pressure drop, etc. In this paper are analyzed the phenomenon of cavitations’ and water hammer through the mathematical model and based in the calculations are taken suitable measures in order to avoid such phenomena in the main drinking water supply system for residents of the city of Prishtina, Podujeva, Fushë Kosova and Obiliqi
Investigation of Factors Affecting Immunotherapy Treatment Results by Binary Logistic Regression and Classification Analysis
No full textThere are many factors that affect the success of immunotherapy treatment. In addition to the clinical examination, the investigation of these factors by different methods contributes to the researchers on prior knowledge and time. In this study, it was aimed to evaluate the application of logistic regression and data mining methods to evaluate the success of post-immunotherapy treatment. Bilateral logistic regression analysis with WTA and classification analysis with Weka were used to evaluate whether immunotherapy treatment was successful for warts. Decision tree structure is also discussed to determine the variables that affect classification success. According to the logistic regression result, the model is important because the probe. 0.022 <0.05. The classification result for the logistic regression model was calculated as 85.56%. This result shows that the model is successful. Data mining experiments were carried out with different classification algorithms. The best result was found in decision trees (with J48 algorithm) with 85.56% accuracy rate. According to the J48 algorithm decision tree structure, the variables that affect the outcome of the treatment were recorded as time, number of warts and age, respectively. Study results show that both methods yield parallel results. Decision tree algorithm is used as an alternative to classical statistical models. In particular, in cases where clinical research is limited, it will benefit researchers on topics such as transition to analysis, preliminary information gathering, time and effort
FPGA-Based Intelligent Traffic Controller with Remote Operation Mode
No full textThis paper covers the design and implementation of an intelligent traffic management system for an isolated intersection. The vehicular traffic management system employs Field Programmable Gate Array (FPGA) as the central decision-making unit and combines its speed and high number of I/O with other system components such as the ESP8266 Wi-Fi module, to record real-time traffic information and apportion greentime for each phase of traffic signal. The design and implementation incorporate three different operational modes namely, fixed time mode, sensor actuated mode and remote control mode, to alleviate vehicular traffic congestion and also reduce the risk of accidents at intersections. The incorporation of remote control mode, which enables an authorized personnel to remotely control the traffic, using a cloud-based application running on a portable device, makes this system different from previous works. Simulation using a prototype of the model on a model intersection, shows that the system can reduce waiting time and increase throughput at the intersections