Search results for: Ebrahim Rajabzadeh Ghatrami
55 Exploring the Impact of Additive Manufacturing on Supply Chains: A Game-Theoretic Analysis of Manufacturer-Retailer Dynamics
Authors: Mohammad Ebrahim Arbabian
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This paper investigates the impact of 3D printing, also known as additive manufacturing, on a multi-item supply chain comprising a manufacturer and retailer. Operating under a wholesale-price contract and catering to stochastic customer demand, this study delves into the largely unexplored realm of how 3D printing technology reshapes supply chain dynamics. A distinguishing aspect of 3D printing is its versatility in producing various product types, yet its slower production pace compared to traditional methods poses a challenge. We analyze the trade-off between 3D printing's limited capacity and its enhancement of production flexibility. By delineating the economic circumstances favoring 3D printing adoption by the manufacturer, we establish the Stackelberg equilibrium in the retailer-manufacturer game. Additionally, we determine optimal order quantities for the retailer considering 3D printing as an option for the manufacturer, ascertain optimal wholesale prices in the presence of 3D printing, and compute optimal profits for both parties involved in the supply chain.Keywords: additive manufacturing, supply chain management, contract theory, Stackelberg game, optimization
Procedia PDF Downloads 6154 Benders Decomposition Approach to Solve the Hybrid Flow Shop Scheduling Problem
Authors: Ebrahim Asadi-Gangraj
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Hybrid flow shop scheduling problem (HFS) contains sequencing in a flow shop where, at any stage, there exist one or more related or unrelated parallel machines. This production system is a common manufacturing environment in many real industries, such as the steel manufacturing, ceramic tile manufacturing, and car assembly industries. In this research, a mixed integer linear programming (MILP) model is presented for the hybrid flow shop scheduling problem, in which, the objective consists of minimizing the maximum completion time (makespan). For this purpose, a Benders Decomposition (BD) method is developed to solve the research problem. The proposed approach is tested on some test problems, small to moderate scale. The experimental results show that the Benders decomposition approach can solve the hybrid flow shop scheduling problem in a reasonable time, especially for small and moderate-size test problems.Keywords: hybrid flow shop, mixed integer linear programming, Benders decomposition, makespan
Procedia PDF Downloads 18853 Assessment of Golestan Dam Break Using Finite Volume Method
Authors: Ebrahim Alamatian, Seyed Mehdi Afzalnia
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One of the most vital hydraulic structures is the dam. Regarding the unrecoverable damages which may occur after a dam break phenomenon, analyzing dams’ break is absolutely essential. GOLESTAN dam is located in the western South of Mashhad city in Iran. GOLESTAN dam break might lead to severe problems due to adjacent tourist and entertainment areas. In this paper, a numerical code based on the finite volume method was applied for assessing the risk of GOLESTAN dam break. As to this issue, first, a canal with a triangular barrier was modeled so as to verify the capability of the concerned code. Comparing analytical, experimental and numerical results showed that water level in the model results is in a good agreement with the similar water level in the analytical solutions and experimental data. The results of dam break modeling are revealed that two of the bridges, that are PARTOIE and NAMAYESHGAH, located downstream in the flow direction, are at risk following the potential GOLESTAN dam break. Therefore, the required times to conduct the precautionary measures at bridges were calculated at about 12 and 21 minutes, respectively. Thus, it is crucial to announce people about the possible risks of the dam break in order to decrease likely losses.Keywords: numerical model, shallow water equations, GOLESTAN dam break, dry and wet beds modeling
Procedia PDF Downloads 14452 A New Method to Winner Determination for Economic Resource Allocation in Cloud Computing Systems
Authors: Ebrahim Behrouzian Nejad, Rezvan Alipoor Sabzevari
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Cloud computing systems are large-scale distributed systems, so that they focus more on large scale resource sharing, cooperation of several organizations and their use in new applications. One of the main challenges in this realm is resource allocation. There are many different ways to resource allocation in cloud computing. One of the common methods to resource allocation are economic methods. Among these methods, the auction-based method has greater prominence compared with Fixed-Price method. The double combinatorial auction is one of the proper ways of resource allocation in cloud computing. This method includes two phases: winner determination and resource allocation. In this paper a new method has been presented to determine winner in double combinatorial auction-based resource allocation using Imperialist Competitive Algorithm (ICA). The experimental results show that in our new proposed the number of winner users is higher than genetic algorithm. On other hand, in proposed algorithm, the number of winner providers is higher in genetic algorithm.Keywords: cloud computing, resource allocation, double auction, winner determination
Procedia PDF Downloads 35951 Small Fixed-Wing UAV Physical Based Modeling, Simulation, and Validation
Authors: Ebrahim H. Kapeel, Ehab Safwat, Hossam Hendy, Ahmed M. Kamel, Yehia Z. Elhalwagy
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Motivated by the problem of the availability of high-fidelity flight simulation models for small unmanned aerial vehicles (UAVs). This paper focuses on the geometric-mass inertia modeling and the actuation system modeling for the small fixed-wing UAVs. The UAV geometric parameters for the body, wing, horizontal and vertical tail are physically measured. Pendulum experiment with high-grade sensors and data analysis using MATLAB is used to estimate the airplane moment of inertia (MOI) model. Finally, UAV’s actuation system is modeled by estimating each servo transfer function by using the system identification, which uses experimental measurement for input and output angles through using field-programmable gate array (FPGA). Experimental results for the designed models are given to illustrate the effectiveness of the methodology. It also gives a very promising result to finalize the open-loop flight simulation model through modeling the propulsion system and the aerodynamic system.Keywords: unmanned aerial vehicle, geometric-mass inertia model, system identification, Simulink
Procedia PDF Downloads 17950 A Comparative Assessment of Membrane Bioscrubber and Classical Bioscrubber for Biogas Purification
Authors: Ebrahim Tilahun, Erkan Sahinkaya, Bariş Calli̇
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Raw biogas is a valuable renewable energy source however it usually needs removal of the impurities. The presence of hydrogen sulfide (H2S) in the biogas has detrimental corrosion effects on the cogeneration units. Removal of H2S from the biogas can therefore significantly improve the biogas quality. In this work, a conventional bioscrubber (CBS), and a dense membrane bioscrubber (DMBS) were comparatively evaluated in terms of H2S removal efficiency (RE), CH4 enrichment and alkaline consumption at gas residence times ranging from 5 to 20 min. Both bioscrubbers were fed with a synthetic biogas containing H2S (1%), CO2 (39%) and CH4 (60%). The results show that high RE (98%) was obtained in the DMBS when gas residence time was 20 min, whereas slightly lower CO2 RE was observed. While in CBS system the outlet H2S concentration was always lower than 250 ppmv, and its H2S RE remained higher than 98% regardless of the gas residence time, although the high alkaline consumption and frequent absorbent replacement limited its cost-effectiveness. The result also indicates that in DMBS when the gas residence time increased to 20 min, the CH4 content in the treated biogas enriched upto 80%. However, while operating the CBS unit the CH4 content of the raw biogas (60%) decreased by three fold. The lower CH4 content in CBS was probably caused by extreme dilution of biogas with air (N2 and O2). According to the results obtained here the DMBS system is a robust and effective biotechnology in comparison with CBS. Hence, DMBS has a better potential for real scale applications.Keywords: biogas, bioscrubber, desulfurization, PDMS membrane
Procedia PDF Downloads 22649 CFD Modeling of Mixing Enhancement in a Pitted Micromixer by High Frequency Ultrasound Waves
Authors: Faezeh Mohammadi, Ebrahim Ebrahimi, Neda Azimi
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Use of ultrasound waves is one of the techniques for increasing the mixing and mass transfer in the microdevices. Ultrasound propagation into liquid medium leads to stimulation of the fluid, creates turbulence and so increases the mixing performance. In this study, CFD modeling of two-phase flow in a pitted micromixer equipped with a piezoelectric with frequency of 1.7 MHz has been studied. CFD modeling of micromixer at different velocity of fluid flow in the absence of ultrasound waves and with ultrasound application has been performed. The hydrodynamic of fluid flow and mixing efficiency for using ultrasound has been compared with the layout of no ultrasound application. The result of CFD modeling shows well agreements with the experimental results. The results showed that the flow pattern inside the micromixer in the absence of ultrasound waves is parallel, while when ultrasound has been applied, it is not parallel. In fact, propagation of ultrasound energy into the fluid flow in the studied micromixer changed the hydrodynamic and the forms of the flow pattern and caused to mixing enhancement. In general, from the CFD modeling results, it can be concluded that the applying ultrasound energy into the liquid medium causes an increase in the turbulences and mixing and consequently, improves the mass transfer rate within the micromixer.Keywords: CFD modeling, ultrasound, mixing, mass transfer
Procedia PDF Downloads 18248 The Effect of Behavioral and Risk Factors of Investment Growth on Stock Returns
Authors: Majid Lotfi Ghahroud, Seyed Jalal Tabatabaei, Ebrahim Karami, AmirArsalan Ghergherechi, Amir Ali Saeidi
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In this study, the relationship between investment growth and stock returns of companies listed in Tehran Stock Exchange and whether their relationship -behavioral or risk factors- are discussed. Generally, there are two perspectives; risk-based approach and behavioral approach. According to the risk-based approach due to increase investment, systemic risk and consequently the stock returns are reduced. But due to the second approach, an excessive optimism or pessimism leads to assuming stock price with high investment growth in the past, higher than its intrinsic value and the price of stocks with lower investment growth, less than its intrinsic value. The investigation period is eight years from 2007 to 2014. The sample consisted of all companies listed on the Tehran Stock Exchange. The method is a portfolio test, and the analysis is based on the t-student test (t-test). The results indicate that there is a negative relationship between investment growth and stock returns of companies and this negative correlation is stronger for firms with higher cash flow. Also, the negative relationship between asset growth and stock returns is due to behavioral factors.Keywords: behavioral theory, investment growth, risk-based theory, stock returns
Procedia PDF Downloads 15647 Optimization of Turbocharged Diesel Engines
Authors: Ebrahim Safarian, Kadir Bilen, Akif Ceviz
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The turbocharger and turbocharging have been the inherent component of diesel engines, so that critical parameters of such engines, as BSFC(Brake Specific Fuel Consumption) or thermal efficiency, fuel consumption, BMEP(Brake Mean Effective Pressure), the power density output and emission level have been improved extensively. In general, the turbocharger can be considered as the most complex component of diesel engines, because it has closely interrelated turbomachinery concepts of the turbines and the compressors to thermodynamic fundamentals of internal combustion engines and stress analysis of all components. In this paper, a waste gate for a conventional single stage radial turbine is investigated by consideration of turbochargers operation constrains and engine operation conditions, without any detail designs in the turbine and the compressor. Amount of opening waste gate which extended between the ranges of full opened and closed valve, is demonstrated by limiting compressor boost pressure ratio. Obtaining of an optimum point by regard above mentioned items is surveyed by three linked meanline modeling programs together which consist of Turbomatch®, Compal®, Rital®madules in concepts NREC® respectively.Keywords: turbocharger, wastegate, diesel engine, concept NREC programs
Procedia PDF Downloads 24346 Experimental and Analytical Investigation of Seismic Behavior of Concrete Beam-Column Joints Strengthened by Fiber-Reinforced Polymers Jacketing
Authors: Ebrahim Zamani Beydokhti, Hashem Shariatmadar
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This paper presents an experimental and analytical investigation on the behavior of retrofitted beam-column joints subjected to reversed cyclic loading. The experimental program comprises 8 external beam–column joint connection subassemblages tested in 2 phases; one was the damaging phase and second was the repairing phase. The beam-column joints were no seismically designed, i.e. the joint, beam and column critical zones had no special transverse stirrups. The joins were tested under cyclic loading in previous research. The experiment had two phases named damage phase and retrofit phase. Then the experimental results compared with analytical results achieved from modeling in OpenSees software. The presence of lateral slab and the axial load amount were analytically investigated. The results showed that increasing the axial load and presence of lateral slab increased the joint capacity. The presence of lateral slab increased the dissipated energy, while the axial load had no significant effect on it.Keywords: concrete beam-column joints, CFRP sheets, lateral slab, axial load
Procedia PDF Downloads 14345 Providing a Suitable Model for Launching New Home Appliances Products to the Market
Authors: Ebrahim Sabermaash Eshghi, Donna Sandsmark
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In changing modern economic conditions of the world, one the most important issues facing managers of firms, is increasing the sales and profitability through sales of newly developed products. This is while purpose of decreasing unnecessary costs is one of the most essential programs of smart managers for more implementation with new conditions in current business. In modern life, condition of misgiving is dominant in all of the industries. Accordingly, in this research, influence of different aspects of presenting products to the market is investigated. This study is done through a Quantitative-Qualitative (Interviews and Questionnaire) approach. In sum, 103 of informed managers and experts of Pars-Khazar Company have been examined through census. Validity of measurement tools was approved through judgments of experts. Reliability of tools was gained through Cronbach's alpha coefficient in size of 0.930 and in sum, validity and reliability of tools were approved generally. Results of regression test revealed that the influence of all aspects of product introduction supported the performance of product, positively and significantly. In addition that influence of two new factors raised from the interview, namely Human Resource Management and Management of product’s pre-test on performance of products was approved.Keywords: introducing products, performance, home appliances, price, advertisement, production
Procedia PDF Downloads 21144 Evaluation of the Ardabil City Environmental Potential for Urban Development
Authors: Seiied Taghi Seiied Safavian, Ebrahim Fataei, Taghi Ebadi
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Urbanized population increasing has been a major driving force for physical development and expansion. In this regard, selecting optimal management strategies for sustainable development of cities as the most important population centers has gotten more attention by the city managers. One of the most important issues in planning a sustainable development is environmental sustainability. In this research, identifying the optimal physical development strategies of Ardabil city in the future condition have been investigated based on land-use planning principles and regularities. Determination of suitable lands of urban development was conducted through natural variables comprised of slope, topography, geology, distance from fault, underground water's depth, land-use strategies and earth shape using hierarchical process method (AHP) in Geographical information system (GIS). Region's potential capabilities and talents were estimated by environmental elements extraction and its measurement based on environmental criteria. Consequently, specified suitable areas for Ardabil city development were introduced. Results of this research showed that the northern part of the Ardabil city is the most suitable sites for physical development of this city regarding the environmental sustainability criteria.Keywords: urban development, environmental sustainability, Ardabil city, AHP, GIS
Procedia PDF Downloads 43043 Sensitivity Analysis of External-Rotor Permanent Magnet Assisted Synchronous Reluctance Motor
Authors: Hadi Aghazadeh, Seyed Ebrahim Afjei, Alireza Siadatan
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In this paper, a proper approach is taken to assess a set of the most effective rotor design parameters for an external-rotor permanent magnet assisted synchronous reluctance motor (PMaSynRM) and therefore to tackle the design complexity of the rotor structure. There are different advantages for introducing permanent magnets into the rotor flux barriers, some of which are to saturate the rotor iron ribs, to increase the motor torque density and to improve the power factor. Moreover, the d-axis and q-axis inductances are of great importance to simultaneously achieve maximum developed torque and low torque ripple. Therefore, sensitivity analysis of the rotor geometry of an 8-pole external-rotor permanent magnet assisted synchronous reluctance motor is performed. Several magnetically accurate finite element analyses (FEA) are conducted to characterize the electromagnetic performance of the motor. The analyses validate torque and power factor equations for the proposed external-rotor motor. Based upon the obtained results and due to an additional term, permanent magnet torque, added to the reluctance torque, the electromagnetic torque of the PMaSynRM increases.Keywords: permanent magnet assisted synchronous reluctance motor, flux barrier, flux carrier, electromagnetic torque, and power factor
Procedia PDF Downloads 33142 Radial Distribution Network Reliability Improvement by Using Imperialist Competitive Algorithm
Authors: Azim Khodadadi, Sahar Sadaat Vakili, Ebrahim Babaei
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This study presents a numerical method to optimize the failure rate and repair time of a typical radial distribution system. Failure rate and repair time are effective parameters in customer and energy based indices of reliability. Decrease of these parameters improves reliability indices. Thus, system stability will be boost. The penalty functions indirectly reflect the cost of investment which spent to improve these indices. Constraints on customer and energy based indices, i.e. SAIFI, SAIDI, CAIDI and AENS have been considered by using a new method which reduces optimization algorithm controlling parameters. Imperialist Competitive Algorithm (ICA) used as main optimization technique and particle swarm optimization (PSO), simulated annealing (SA) and differential evolution (DE) has been applied for further investigation. These algorithms have been implemented on a test system by MATLAB. Obtained results have been compared with each other. The optimized values of repair time and failure rate are much lower than current values which this achievement reduced investment cost and also ICA gives better answer than the other used algorithms.Keywords: imperialist competitive algorithm, failure rate, repair time, radial distribution network
Procedia PDF Downloads 66841 Effects of Smartphone Social Applications on Elderly People’s Quality of Life
Authors: Seyed Ebrahim Hosseini, Shahbaz Pervez
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As people go through aging, maintenance and improvement of the quality of life become more important for them. To know the role of smartphone technology and communications applications on quality of life, a sample group of old people living in Dar-Iran was selected for a quasi-experimental study. The participants were registered senior inhabitants from public health centers in Dar, Iran in 2022. The number of participants was 39. Participants were randomly categorized into intervention and control groups. A validated Persian version of the Control, Autonomy, Self-realisation, Pleasure scale (CASP-19) scale questionnaire was provided for them which answers were used for the quality of life assessment. The paired t-test between pre-and post-test (t= -8.45, p<.00), post-and follow-up-test (t= -2.12, p=.01), and pre-test and the follow-up test (t= -8.27, p<.00) in the intervention group revealed a considerable mean difference. Based on the results of paired t-test for the control group, this was not significant between pre-test and post-test (t= 1.26, p=.15), post-test and follow-up test (t= .33, p=.67) and pre-test and follow-up test (t= 1.85, p=.08) for quality of life. Considering the educational training associated with it, this study aimed at helping families and aging field practitioners to understand the essentiality of modern communication technology teaching in promoting a greater life quality of the elderly’s community.Keywords: Iranian elderly, quality of life, smartphone, social applications, CASP-19
Procedia PDF Downloads 14840 5-[Aryloxypyridyl (or Nitrophenyl)]-4H-1,2,4-Triazoles as Flexible Benzodiazepine Analogs: Synthesis, Receptor Binding Affinity and the Lipophilicity-Dependent Anti-Seizure Onset of Action
Authors: Latifeh Navidpour, Shabnam Shabani, Alireza Heidari, Manouchehr Bashiri, Azadeh Ebrahim-Habibi, Soraya Shahhosseini, Hamed Shafaroodi, Sayyed Abbas Tabatabai, Mahsa Toolabi
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A new series of 5-(2-aryloxy-4-nitrophenyl)-4H-1,2,4-triazoles and 5-(2-aryloxy-3-pyridyl)-4H-1,2,4-triazoles, possessing C-3 thio or alkylthio substituents, was synthesized and evaluated for their benzodiazepine receptor affinity and anti-seizure activity. These analogues revealed similar to significantly superior affinity to GABAA/ benzodiazepine receptor complex (IC50 values of 0.04–4.1 nM), relative to diazepam as the reference drug (IC50 value of 2.4 nM). To determine the onset of anti-seizure activity, the time-dependent effectiveness of i.p. administration of compounds on pentylenetetrazole induced seizure threshold was studied and a very good relationship was observed between the lipophilicity (cLogP) and onset of action of studied analogues (r2 = 0.964). The minimum effective dose of the compounds, determined at the time the analogues showed their highest activity, was demonstrated to be 0.025–0.1 mg/kg, relative to diazepam (0.025 mg/kg).Keywords: 1, 2, 4-triazole, flexible benzodiazepines, GABAA/bezodiazepine receptor complex, onset of action, PTZ induced seizure threshold
Procedia PDF Downloads 10439 The Trajectory of the Ball in Football Game
Authors: Mahdi Motahari, Mojtaba Farzaneh, Ebrahim Sepidbar
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Tracking of moving and flying targets is one of the most important issues in image processing topic. Estimating of trajectory of desired object in short-term and long-term scale is more important than tracking of moving and flying targets. In this paper, a new way of identifying and estimating of future trajectory of a moving ball in long-term scale is estimated by using synthesis and interaction of image processing algorithms including noise removal and image segmentation, Kalman filter algorithm in order to estimating of trajectory of ball in football game in short-term scale and intelligent adaptive neuro-fuzzy algorithm based on time series of traverse distance. The proposed system attain more than 96% identify accuracy by using aforesaid methods and relaying on aforesaid algorithms and data base video in format of synthesis and interaction. Although the present method has high precision, it is time consuming. By comparing this method with other methods we realize the accuracy and efficiency of that.Keywords: tracking, signal processing, moving targets and flying, artificial intelligent systems, estimating of trajectory, Kalman filter
Procedia PDF Downloads 45938 Effect of Drought Stress on Yield and Yield Components of Maize Cultivars in Golestan Province
Authors: Mojtaba Esmaeilzad Limoudehi, Ebrahim Amiri
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Water scarcity is now one of the leading challenges for human societies. In this regard, recognizing the relationship between soil, water, plant growth, and plant response to stress is very significant. In this paper, considering the importance of drought stress and the role of choosing suitable cultivars in resistance against drought, a split-plot experiment using early, intermediate, and late-maturing cultivars was carried out in Katul filed, Golestan province during two cultivation years of 2015 and 2016. The main factor was irrigation intervals at four levels, including 7 days, 14 days, 21 days, and 28 days. The subfactor was the subplot of six maize cultivars (two early maturing cultivars, two medium maturing cultivars, and two late-maturing cultivars). The results of variance analysis have revealed that irrigation interval and cultivars treatment have significant effects on the number of grain in each corn, number of rows in each corn, number of grain per row, the weight of 1000 grains, grain yield, and biomass yield. Although, the interaction of these two factors on the mentioned attributes was meaningful. The best grain yield was achieved at 7 days irrigation interval and late maturing maize cultivars treatment, which was equal to 12301 kg/ha.Keywords: corn, growth period, optimization, stress
Procedia PDF Downloads 14337 An Implementation of Fuzzy Logic Technique for Prediction of the Power Transformer Faults
Authors: Omar M. Elmabrouk., Roaa Y. Taha., Najat M. Ebrahim, Sabbreen A. Mohammed
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Power transformers are the most crucial part of power electrical system, distribution and transmission grid. This part is maintained using predictive or condition-based maintenance approach. The diagnosis of power transformer condition is performed based on Dissolved Gas Analysis (DGA). There are five main methods utilized for analyzing these gases. These methods are International Electrotechnical Commission (IEC) gas ratio, Key Gas, Roger gas ratio, Doernenburg, and Duval Triangle. Moreover, due to the importance of the transformers, there is a need for an accurate technique to diagnose and hence predict the transformer condition. The main objective of this technique is to avoid the transformer faults and hence to maintain the power electrical system, distribution and transmission grid. In this paper, the DGA was utilized based on the data collected from the transformer records available in the General Electricity Company of Libya (GECOL) which is located in Benghazi-Libya. The Fuzzy Logic (FL) technique was implemented as a diagnostic approach based on IEC gas ratio method. The FL technique gave better results and approved to be used as an accurate prediction technique for power transformer faults. Also, this technique is approved to be a quite interesting for the readers and the concern researchers in the area of FL mathematics and power transformer.Keywords: dissolved gas-in-oil analysis, fuzzy logic, power transformer, prediction
Procedia PDF Downloads 14436 An Evaluation of Kahoot Application and Its Environment as a Learning Tool
Authors: Muhammad Yasir Babar, Ebrahim Panah
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Over the past 20 years, internet has seen continual advancement and with the advent of online technology, various types of web-based games have been developed. Games are frequently being used among different age groups from baby boomers to generation Z. Games are not only used for entertainment but also utilized as a learning approach transmitting education to a level that is more interesting and effective for students. One of the popular web-based education games is Kahoot with growing popularity and usage, which is being used in different fields of studies. However, little knowledge is available on university students’ perception of Kahoot environment and application for learning subjects. Hence, the objective of the current study is to investigate students’ perceptions of Kahoot application and environment as a learning tool. The study employed a survey approach by distributing Google Forms –created questionnaire, with high level of reliability index, to 62 students (11 males and 51 females). The findings show that students have positive attitudes towards Kahoot application and its environment for learning. Regarding Kahoot application, it was indicated that activities created using Kahoot are more interesting for students, Kahoot is useful for collaborative learning, and Kahoot enhances interest in learning lesson. In terms of Kahoot environment, it was found that using this application through mobile is easy for students, its design is simple and useful, Kahoot-created activities can easily be shared, and the application can easily be used on any platform. The findings of the study have implications for instructors, policymakers and curriculum developers.Keywords: application, environment, Kahoot, learning tool
Procedia PDF Downloads 13335 The Effect of Tribulus Terresteris on Histomorphometrical Changes of Testis Induced by Ethanol Administration in Male Wistar Rats
Authors: Arash Esfandiari, Ebrahim Parsaei
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The purpose of this research was to survey the effect of tribulus terresteris on histomorphometrical changes of testis induced by ethanol administration in male wistar rats. Fifteen male wistar rats divided into three groups: 1- control group (n=5). 2- Experimental group I (IP received 1 mg/gr Alcohole 20% for 30 days) (n=5). 3- Experimental group II (IP received 1 mg/gr Alcohole 20% for 30 days and IP received 100 mg/kg tribulus terresteris 15 days before received Alcohole for 45 days) (n=5). All procedures and care of the animals were conducted following protocols approved by the ethical committee (Iranian Society for the Prevention of cruelty to animal, and Iranian Veterinary Organization). Results showed that the thickness of the wall of seminiferous tubule, the weight of testis, the number of spermatogenic cells were decreased in experimental group I. In addition, all of these parameters were increased in experimental group II compared with experimental group I. These decrement of all of parameters in experimental group I with significant difference in comparison control group (p≤ 0.05). But all of parameters had increment in experimental group II with no significant difference compared with control group (p≥ 0.05) and significant difference with experimental group I (p≤ 0.05).It is concluded that tribulus terresteris may prevent from reducing the number of spermatogenic cell that has been created by the consumption of alcohole.Keywords: ethanol, histomorphometric, testis, teribulus terresteris
Procedia PDF Downloads 60534 Investigating the Effect of Industrial Wastewater Application on the Concentration of Nitrate and Phosphate in the Soil of the Land Space of Chaharmahal and Bakhtiari Sefid Dasht Steel Company
Authors: Seyed Alireza Farrokhzad, Seyed Amin Alavi, Ebrahim Panahpour
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The use of industrial wastewater affects the properties of soil, including its chemical properties. This research was conducted randomly in order to investigate the effect of industrial wastewater application on the concentration of nitrate and phosphate in loamy soil in the land space of Chaharmahal and Bakhtiari Sefid Dasht Steel Company. Industrial wastewater was added in ten irrigation periods in the three months of summer 2022 and was used in a part of the land space of the factory. After finishing the irrigation process with wastewater, the soil nitrate and phosphate values were measured at the depths of 0-25, 25-50 and 50-100 cm. The results showed that adding sewage to the soil increased nitrate and phosphate. The increase of these ions in the soil became loamy. Also, the results showed that the amount of phosphate in the soil decreases with increasing depth, while the amount of nitrate in the soil increases with increasing depth, which is due to the high mobility of nitrate along the soil profile. Also, with the increase in the level of use of wastewater, the amount of nitrate accumulation in the lower layers of the soil increased.Keywords: industrial wastewater, soil chemical properties, loamy texture, land space
Procedia PDF Downloads 8433 The Design and Implementation of a Calorimeter for Evaluation of the Thermal Performance of Materials: The Case of Phase Change Materials
Authors: Ebrahim Solgi, Zahra Hamedani, Behrouz Mohammad Kari, Ruwan Fernando, Henry Skates
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The use of thermal energy storage (TES) as part of a passive design strategy can reduce a building’s energy demand. TES materials do this by increasing the lag between energy consumption and energy supply by absorbing, storing and releasing energy in a controlled manner. The increase of lightweight construction in the building industry has made it harder to utilize thermal mass. Consequently, Phase Change Materials (PCMs) are a promising alternative as they can be manufactured in thin layers and used with lightweight construction to store latent heat. This research investigates utilizing PCMs, with the first step being measuring their performance under experimental conditions. To do this requires three components. The first is a calorimeter for measuring indoor thermal conditions, the second is a pyranometer for recording the solar conditions: global, diffuse and direct radiation and the third is a data-logger for recording temperature and humidity for the studied period. This paper reports on the design and implementation of an experimental setup used to measure the thermal characteristics of PCMs as part of a wall construction. The experimental model has been simulated with the software EnergyPlus to create a reliable simulation model that warrants further investigation.Keywords: phase change materials, EnergyPlus, experimental evaluation, night ventilation
Procedia PDF Downloads 25632 An Empirical Research on Customer Knowledge Management in the Iranian Banks
Authors: Ebrahim Gharleghi
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This paper aims to examine how customer knowledge management (CKM) can be implemented in Iranian Banks in practice, with the focus on the human resource (people, technology and processes) as important factors of CKM. A conceptual model of an analytical CKM strategy for CKM in this Iranian Banks is developed from the findings and literature review. This article has been based on interviews and distributing the questionnaire. Data were collected from 260 managers from bank managers. The paper finds that hypotheses were tested using student’s t-test (one-sample t-test), Pearson correlation analysis and regression analysis. Test of hypotheses revealed that human, technology and processes factors positively and significantly influenced the implementation of CKM practices. These findings tend to corroborate our conceptual model. Human factor of CKM was found to be more significantly affecting appropriate CKM implementation than others CKM factors, indicating that this factor is more important than the others aspects of CKM. On the other hand, this factor is appropriate in Iranian Banks. Process is in second part and technology is in final part. This indicates that technology infrastructures are so weak in Iranian Banks for CKM implementation. In this paper there is little or no empirical evidence investigating the amount of the execution of the CKM in Iranian Banks. This paper rectifies this imbalance by clarifying the significance human, technology and processes factors in CKM implementation.Keywords: knowledge management, customer relationship management, customer knowledge management, integration, people, technology, process
Procedia PDF Downloads 27431 Interaction of Hemoglobin with Sodium Dodecyl Sulfate and Ascorbic Acid: A Chemometrics Study
Authors: Radnoosh Mirzajani, Ebrahim Mirzajani, Heshmatollah Ebrahimi-Najafabadi
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Introduction: Hydrogen peroxide can be produced over the interaction of sodium dodecyl sulfate (SDS) with hemoglobin which would facilitate the oxidation process of hemoglobin. The presence of ascorbic acid (AA) can hinder the extreme oxidation of oxyhemoglobin. Methods: Hemoglobin was purified from blood samples according to the method of Williams. UV-V is spectra of Hb solutions mixed with different concentrations of SDS and AA were recorded. Chemical components, concentration, and spectral profiles were estimated using MCR-ALS techniques. Results: The intensity of soret band of OxyHb decreased due to the interaction of Hb with SDS. Furthermore, changes were also observed for peaks at 575 and 540. Subspace plots confirm the presence of OxyHb, MetHb, and Hemichrom in each mixture. The resolved concentration profiles using MCR-ALS reveal that the mole fraction of OxyHb increased upon the presence of AA up to a concentration level of 3 mM. The higher concentration of AA shows a reverse effect. AA demonstrated a dual effect on the interaction of hemoglobin with SDS. AA disturbs the interaction of SDS and hemoglobin and exhibits an antioxidative effect. However, it caused a tiny decrease in the mole fraction of OxyHb. Conclusions: H2O2 produces upon the interaction of OxyHb with SDS. Oxidation of OxyHb facilitates due to overproduction of H2O2. Ascorbic acid interacts with H2O2 to form dehydroascorbic acid. Furthermore, the available free SDS was reduced because the Gibbs free energy for micelle production of SDS became more negative in the presence of AA.Keywords: hemoglobin, ascorbic acid, sodium dodecyl sulfate, multivariate curve resolution, antioxidant
Procedia PDF Downloads 11930 Novel Development on Orthopedic Prosthesis by Nanocrystalline Hydroxyapatite Nanocomposite Coated on 316 L Stainless Steel
Authors: Neriman Ozada, Ebrahim Karamian, Amirsalar Khandan, Sina Ghafoorpoor Yazdi
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Natural hydroxyapatite, NHA, coatings on the surface of 316 L stainless steel implants has been widely employed in order to achieve better osteoconductivity. For coating, the plasma spraying method is generally used because they ensure adhesion between the coating and the 316 L stainless steel (SS) surface. Some compounds such as zircon (ZrSiO4) is employed as an additive in an attempt to improve HA’s mechanical properties such as wear resistance and hardness. In this study wear resistance has been carried out in different chemical compositions of coating. Therefore, nanocomposites based on NHA containing of 0 wt.%, 5 wt.%, 10 wt.%, and 15 wt.% of zircon were used as a coating on the SS implants. The samples consisted of NHA, derived from calf heated at 850 °C for 3 h. The composite mixture was coated on SS by plasma spray method. The results were estimated using the scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques were utilized to characterize the shape and size of NHA powder. Disc wear test and Vickers hardness were utilized to characterize the coated nanocomposite samples. The prepared NHA powder had nano-scale morphological structure with the mean crystallite size of 30-50 nm in diameter. The wear resistance are almost 320, 380, 415, and 395 m/g and hardness are approximately 376, 391, 420, 410 VHN in ceramic composite materials containing ZrSiO4. The results have been shown that the best wear resistance and hardness occurred in the sample coated by NHA/ZrSiO4 containing of 10 wt.% of zircon.Keywords: zircon, 316 L stainless steel, wear resistance, orthopedic applications, plasma spray
Procedia PDF Downloads 43329 Feasibility Study of Iraq' Decomposition and Its Effects on the Region
Authors: Ebrahim Rahmani, Siyamak Moazeni
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According to the Iraq's first constitutional law (approved 2005), Iraq is an independent with sovereignty and its governmental structure is parliamentary democratic republic and federal. Even in reforms in 2009, this article of law did not changed at all. But considering the existence of this emphasis and clarity which is mentioned in the law, different and sometimes contradictory interpretations and positions are expressed about federalism in the way that we can say, considering the importance of the matter, federalism is a focus point to create and expansion of the cold war among leaders of different groups of the country. Iraq's today political and security position has granted the suitable opportunity to Iraq's Kurdistan in appearing of the recent security crisis to increase its share from the central political power or to achieve to its independent dream. The federalism the weakest point of Iraq's territorial integrity in a way that if different groups do not come to a consensus about it and do not think about a mechanism which is accepted by all of them, this can effect on and Iraq's political stability and security. Iraq's Kurdistan follows the option of disintegration and separation under the shadow of political and security changes, even with existence of some Iraqi groups' hopes regarding the improvement of situation after parliament election and also considering Masoud Barezani's power will for separation from Iraq as well as regarding special international changes and disintegration of Karime from Ukraine and ISIS crises; concerns have been created among regional and international powers and interior players. In this article, a paradox due constitutional law about federalism, Iraq's central government view and its politicians to the matter and the regional effect of this action on region's geopolitics are reviewed as well.Keywords: constitutional law, federalism, decomposition, Iraq's Kurdistan
Procedia PDF Downloads 32828 Topical Negative Pressure for Autologous Fat Grafting in Breast Augmentation
Authors: Mohamed Eftal Bin Mohamed Ebrahim, Alexander Varey
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Aim: Topical negative pressure has been shown to enhance angiogenesis during wound healing, both for open and closed wounds. Since angiogenesis is a key requirement for successful fat grafting, there may be a role for topical negative pressure as a means of enhancing the take rate during autologous fat grafting to breasts. Here we present a systematic review of the literature on this topic. Methods: Ovid and Embase were utilized, with searches ranging between 1960 – 2019. Terms (“Liposculpting” OR “Fat grafting” OR “Lipofilling” OR “Lipograft” OR “Fat transfer”) AND (“Negative Pressure” OR “Brava” OR “Kiwi”) AND (“Breast”) were merged as keywords. Inclusion criteria were females, autologous fat graft to breast with topical negative pressure prior to the procedure. Studies were excluded if there was no primary endpoint or non-original article. Results: Upon reviewing 219 articles, 2 met inclusion criteria. A total of 565 and 46 breasts in each article were treated respectively using the negative pressure device BRAVA®, with each cohort having different pre-and post-operative pressure settings. Khouri et al. cohort had higher graft survival (79%) compared to Del Vecchio et al. cohort (64%); however, the latter had fewer complications compared to Khouri’s cohort, e.g., fat necrosis, pneumothorax and infection. Conclusion: There is limited evidence regarding the use of topical negative pressure for fat grafting to the breasts. However, in the two studies published, the reported rates of success are high, suggesting there may be a benefit. Consequently, a randomized controlled trial on this area is required.Keywords: fat grafting, lipograft, negative pressure, breast, breast augmentation, brava
Procedia PDF Downloads 19227 The Effects of the War between Russia and Ukraine on Qatar’s Fossil and Renewable Energy Policies
Authors: Rahmat Hajimineh, Ebrahim Rezaei Rad
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The war between Russia and Ukraine is considered a very important event in international relations, especially after the end of the Cold War, a war that has had wide dimensions since its beginning. Dimensions that, in addition to political issues, have especially affected the world economy and especially the two countries. The most important issue in the field of the economy that was affected by the war between Russia and Ukraine was the issue of energy. Russia is one of the largest producers and suppliers of natural gas for European countries, and 40% of European gas is supplied by Russia. For this reason, it is natural that European countries have problems in this regard. On the other hand, Ukraine is considered the gateway to Europe for Russia regarding the export of natural gas. The war in Ukraine has had severe effects on gas and energy in Europe. From this point of view, European countries are looking to diversify their energy path by switching to renewable energies, and they are also looking at other energy-producing countries like Qatar to meet their energy needs. In this article, we are trying to investigate the impact of the war between Russia and Ukraine on Qatar's policies in the field of fossil and renewable energy. The descriptive-analytical method and the theoretical framework of energy security have been used to review this article. Based on this, the article examines the situation of fossil and renewable energies in Qatar and, on the other hand, the effects of the war in Ukraine on both energies in Qatar. The findings of this article also indicate that Qatar has made changes in its energy policies after the war in Ukraine, which seems to be possible due to its high potential, especially in the field of renewable and fossil energy. There is an export of surplus production of this country to other countries, especially European countries.Keywords: Ukraine War, fossil fuels, renewable energy, energy security, Qatar
Procedia PDF Downloads 9926 Outcomes of Live Renal Donors with a History of Nephrolithiasis
Authors: Bin Mohamed Ebrahim, Aminesh Singla, Henry Pleass
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Aim: There is an ongoing gap in renal transplantation between organs available for donation and recipients on the waiting list. Live donors with pre-existing or a history of renal calculi were thought to be a relative contraindication due to safety concerns for donors. We aim to review current literature assessing outcomes of donors who were found to have a history of renal calculi. Methods: Ovid and Embase were searched between 1960 to 2021 using key terms and Medical Subject Headings (MeSH) – nephrolithiasis, renal stones, renal transplantation and renal graft. Articles included conference proceedings and journal articles and were not excluded based on patient numbers. Studies were excluded if the specific organ was not identified, duplicated reports found or if post-transplant outcomes were not recorded. Outcomes were donor’s renal function or renal calculi recurrence postoperatively. Results: Upon reviewing 344 articles, 14 manuscripts met inclusion criteria. A total of 152 live donors were identified as having pre-existing or with a history of renal calculi at pre-operative workup. The mean stone size was 2.6 4mm (1 – 16) with a mean follow-up duration of 31.8 months (1 – 96). Seven studies had both outcomes. None showed renal complications or stone recurrence. The remaining studies contained 2 out of 84 patients having recurrent nephrolithiasis. Conclusion: Data suggests minimal morbidity involved for live renal donors with a history of nephrolithiasis. This should encourage surgeons to continue recruiting such donors for kidney transplantation.Keywords: renal transplantation, renal graft, nephrolithiasis, renal calculi, live donor
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