Search results for: Abdul Hadi Mahmud
698 Modeling and Minimizing the Effects of Ferroresonance for Medium Voltage Transformers
Authors: Mohammad Hossein Mohammadi Sanjani, Ashknaz Oraee, Arian Amirnia, Atena Taheri, Mohammadreza Arabi, Mahmud Fotuhi-Firuzabad
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Ferroresonance effects cause overvoltage in medium voltage transformers and isolators used in electrical networks. Ferroresonance effects are nonlinear and occur between the network capacitor and the nonlinear inductance of the voltage transformer during saturation. This phenomenon is unwanted for transformers since it causes overheating, introduction of high dynamic forces in primary coils, and rise of voltage in primary coils for the voltage transformer. Furthermore, it results in electrical and thermal failure of the transformer. Expansion of distribution lines, design of the transformer in smaller sizes, and the increase of harmonics in distribution networks result in an increase of ferroresonance. There is limited literature available to improve the effects of ferroresonance; therefore, optimizing its effects for voltage transformers is of great importance. In this study, comprehensive modeling of a medium voltage block-type voltage transformer is performed. In addition, a recent model is proposed to improve the performance of voltage transformers during the occurrence of ferroresonance using damping oscillations. Also, transformer design optimization is presented in this study to show further improvements in the performance of the voltage transformer. The recently proposed model is experimentally tested and verified on a medium voltage transformer in the laboratory, and simulation results show a large reduction of the effects of ferroresonance.Keywords: optimization, voltage transformer, ferroresonance, modeling, damper
Procedia PDF Downloads 101697 Optical and Dielectric Properties of Self-Assembled 0D Hybrid Organic-Inorganic Insulator
Authors: S. Kassou, R. El Mrabet, A. Belaaraj, P. Guionneau, N. Hadi, T. Lamcharfi
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The organic–inorganic hybrid perovskite-like [C6H5C2H4NH3]2ZnCl4 (PEA-ZnCl4) was synthesized by saturated solutions method. X-ray powder diffraction, Raman spectroscopy, UV-visible transmittance, and capacitance meter measurements have been used to characterize the structure, the functional groups, the optical parameters, and the dielectric constants of the material. The material has a layered structure. The optical transmittance (T %) was recorded and applied to deduce the absorption coefficient (α) and optical band gap (Eg). The hybrid shows an insulator character with a direct band gap about 4.46 eV, and presents high dielectric constants up to a frequency of about 105 Hz, which suggests a ferroelectric behavior. The reported optical and dielectric properties can help to understand the fundamental properties of perovskite materials and also to be used for optimizing or designing new devices.Keywords: dielectric constants, optical band gap (eg), optical parameters, Raman spectroscopy, self-assembly organic inorganic hybrid
Procedia PDF Downloads 402696 A Computer-Aided System for Detection and Classification of Liver Cirrhosis
Authors: Abdel Hadi N. Ebraheim, Eman Azomi, Nefisa A. Fahmy
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This paper designs and implements a computer-aided system (CAS) to help detect and diagnose liver cirrhosis in patients with Chronic Hepatitis C. Our system reduces the required features (tests) the patient is asked to do to tests to their minimal best most informative subset of tests, with a diagnostic accuracy above 99%, and hence saving both time and costs. We use the Support Vector Machine (SVM) with cross-validation, a Multilayer Perceptron Neural Network (MLP), and a Generalized Regression Neural Network (GRNN) that employs a base of radial functions for functional approximation, as classifiers. Our system is tested on 199 subjects, of them 99 Chronic Hepatitis C.The subjects were selected from among the outpatient clinic in National Herpetology and Tropical Medicine Research Institute (NHTMRI).Keywords: liver cirrhosis, artificial neural network, support vector machine, multi-layer perceptron, classification, accuracy
Procedia PDF Downloads 461695 The Thermal Simulation of Hydraulic Cable Drum Trailers 15-Ton
Authors: Ahmad Abdul-Razzak Aboudi Al-Issa
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Thermal is the main important aspect in any hydraulic system since it is affected on the hydraulic system performance. Therefore must be simulated the hydraulic system -that was designed- in this aspect before constructing it. In this study, an existed expert system was using to simulate the thermal aspect of a designed hydraulic system that will be used in an industrial field. The expert system which is used in this study is (Hydraulic System Calculations), and its symbol (HSC). HSC had been designed and coded in an interactive program userfriendly named (Microsoft Visual Basic 2010).Keywords: fluid power, hydraulic system, thermal and hydrodynamic, expert system
Procedia PDF Downloads 500694 Assessing Green Metrics of Cement Supply Chain in Iran: A Fuzzy DEMATEL Approach
Authors: Hadi Badri Ahmadi, Xuping Wang
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Due to strict regulations and public awareness, corporations should develop policies to effectively decrease the negative environmental effects of their products and enhance their supply chain environmental sustainability. Assessment of environmental issues in the context of many industries has been studied in the previous literature. However, Iran cement industry has received less attention from researchers. Therefore, in this paper, we apply a Decision-Making Trial and Evaluation Laboratory (DEMATEL) approach to assess the relationships among green metrics of Iran cement industry supply chain under fuzzy environment. The study findings provide considerable insight for cement industry managers and experts in order to enhance the environmental sustainability of their supply chain and move towards sustainable development.Keywords: green supply chain, DEMATEL, fuzzy set theory, environmental sustainability, sustainable development, cement industry
Procedia PDF Downloads 413693 Psychological Dominance During and Afterward of COVID-19 Impact of Online-Offline Educational Learning on Students
Authors: Afrin Jaman Bonny, Mehrin Jahan, Zannatul Ferdhoush, Mumenunnessa Keya, Md. Shihab Mahmud, Sharun Akter Khushbu, Sheak Rashed Haider Noori, Sheikh Abujar
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In 2020, the SARS-CoV-2 pandemic had led all the educational institutions to move to online learning platforms to ensure safety as well as the continuation of learning without any disruption to students’ academic life. But after the reopening of those educational institutions suddenly in Bangladesh, it became a vital demand to observe students take on this decision and how much they are comfortable with the new habits. When all educational institutions were ordered to re-open after more than a year, data was collected from students of all educational levels. A Google Form was used to conduct this online survey, and a total of 565 students participated without being pressured. The survey reveals the students' preferences for online and offline education systems, as well as their mental health at the time including their behavior to get back to offline classes depending on getting vaccinated or not. After evaluating the findings, it is clear that respondents' choices vary depending on gender and educational level, with female and male participants experiencing various mental health difficulties and attitudes toward returning to offline classes. As a result of this study, the student’s overall perspective on the sudden reopening of their educational institutions has been analyzed.Keywords: covid-19 epidemic, educational proceeding, university students, school/college students, physical activity, online platforms, mental health, psychological distress
Procedia PDF Downloads 209692 A Longitudinal Study of the Readability of the Chairman’s Narratives in Corporate Reports: Malaysian Evidence
Authors: Azhar Abdul Rahman
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This paper examines the readability of the chairman’s narratives, as determined by the Flesch score, of a Malaysian public listed company’s corporate reports from 1962 to 2009. It partially supports earlier studies which demonstrated that corporate reports were difficult to read, and had shown very negligible decrease in difficulty over time. Net profit to sales and readability was significantly positively correlated but number of financial statements was significantly negatively correlated with readability.Keywords: chairman’s narratives, corporate communications, readability, longitudinal
Procedia PDF Downloads 453691 Secure Intelligent Information Management by Using a Framework of Virtual Phones-On Cloud Computation
Authors: Mohammad Hadi Khorashadi Zadeh
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Many new applications and internet services have been emerged since the innovation of mobile networks and devices. However, these applications have problems of security, management, and performance in business environments. Cloud systems provide information transfer, management facilities, and security for virtual environments. Therefore, an innovative internet service and a business model are proposed in the present study for creating a secure and consolidated environment for managing the mobile information of organizations based on cloud virtual phones (CVP) infrastructures. Using this method, users can run Android and web applications in the cloud which enhance performance by connecting to other CVP users and increases privacy. It is possible to combine the CVP with distributed protocols and central control which mimics the behavior of human societies. This mix helps in dealing with sensitive data in mobile devices and facilitates data management with less application overhead.Keywords: BYOD, mobile cloud computing, mobile security, information management
Procedia PDF Downloads 317690 Application of Golden Ratio in Contemporary Textile Industry and Its Effect on Consumer Preferences
Authors: Rafia Asghar, Abdul Hafeez
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This research aims to determine the influence of Fibonacci numbers and golden ratio through textile designs. This study was carried out by collecting a variety of designs from different textile industries. Top textile designers were also interviewed regarding golden ratio and its application on their designs and design execution process. This study revealed that most of the designs fulfilled the golden ratio and the designs that were according to golden ratio were more favorite to the consumers.Keywords: golden ratio, Fibonacci numbers, textile design, designs
Procedia PDF Downloads 718689 Evaluating the Quality of Private University Websites in Malaysia
Authors: Rubijesmin Abdul Latif
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This paper focuses on evaluating what are quality components of university websites in Malaysia especially the private universities. It is believed that with websites that prioritize quality, the websites will serve its intended users satisfactory. From the compiled analysis of other studies, quality components were identified and tested among 30 randomly selected respondents. Four Malaysia private university websites were compared and the highlights were better understanding of what users want for a quality university website.Keywords: website evaluation, criteria, quality, usability, user experience, university website
Procedia PDF Downloads 371688 The Effects of Different Doses of Caffeine on Young Futsal Players
Authors: Saead Rostami, Seyyed Hadi Hosseini Alavije, Aliakbar Torabi, Mohammad Bekhradi
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This study is about The effects of different doses of caffeine on young Futsal players. Young futsal players of selected ShahinShahr(a city in Esfahan province, Iran) team are sampled (24 people of 18.3±1.9 year- old). All players are members of youth team playing in Esfahan counties league. Having at least 5 years of experience, 2 practices and 1 match per week and lacking any limitation in the past 6 months are the most important requirements for sampling the players. Next, the study topic, its method, its uses, as ell possible risks are explained to the players. They signed a consent letter to take part in the study. Interest in the use of caffeine as an ergogenic aid has increased since the International Olympic Committee lifted the partial ban on its use. Caffeine has beneficial effects on various aspects of athletic performance, but its effects on training have been neglected. The purpose of this study was to investigate the acute effect of caffeine on testosterone and cortisole in young futsal players.Keywords: anabolic, catabolic, performance, testosterone cortisol ratio, RAST test
Procedia PDF Downloads 347687 Real-Time Loop-Mediated Isothermal Amplification Assay for Rapid Detection of Human Papillomavirus 16 in Oral Squamous Cell Carcinoma
Authors: Suharni Mohamad Suharni Mohamad, Nurul Izzati Hamzan Nurul Izzati Hamzan, Norhayu Abdul Rahman Norhayu Abdul Rahman, Siti Suraiya Md Noor Siti Suraiya Md Noor
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Human papillomavirus (HPV) is an important risk factor for development of oral cancer. HPV16 is the most common type found in HPV-positive squamous cell carcinoma. In the present study, we established a real-time loop-mediated isothermal amplification (real-time LAMP) for detection of HPV16. A set of six primers was specially designed to recognize eight distinct sequences of HPV16-E6. Detection and quantification was achieved by real-time monitoring using a real-time turbidimeter based on threshold time required for turbidity in the LAMP reaction. LAMP reagents (MgSO4, dNTPs, Bst polymerase concentrations) and various incubation times and temperatures were optimized. The sensitivity was determined using 10-fold serial dilutions of HPV16 standard strain. The specificity of was evaluated using other HPV genotypes. The optimized method was established with specifically designed primers by real-time detection in approximately 30 min at 65°C. The limit of detection of HPV16 using the LAMP assay was 10 pg/ml that could be detected in 30 min. The LAMP assay was 10 times more sensitive than the conventional PCR in detecting HPV16. No cross-reactivity with other HPV genotypes was observed. This quantitative real-time LAMP assay may improve diagnostic potential for the detection and quantification of HPV16 in clinical samples and epidemiological studies due to its rapidity, simplicity, high sensitivity and specificity. This assay will be further evaluated with HPV DNAs of saliva from patients with oral squamous cell carcinoma. Acknowledgement: This study was financially supported by the ScienceFund Grant, Ministry of Science, Technology and Innovation (305/PPSG/6113219).Keywords: Oral Squamous Cell Carcinoma (OSCC), Human Papillomavirus 16 (HPV16), Loop-Mediated Isothermal Amplification (LAMP), rapid detection
Procedia PDF Downloads 406686 Prognostic Value of C-Reactive Protein (CRP) in SARS-CoV-2 Infection: A Simplified Biomarker of COVID-19 Severity in Sub-Saharan Africa
Authors: Teklay Gebrecherkos, Mahmud Abdulkader, Tobias Rinke De Wit, Britta C. Urban, Feyissa Chala, Yazezew Kebede, Dawit Welday
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Background: C-reactive protein (CRP) levels are a reliable surrogate for interleukin-6 bioactivity that plays a pivotal role in the pathogenesis of cytokine storm associated with severe COVID-19. There is a lack of data on the role of CRP as a determinant of COVID-19 severity status in the African context. Methods: We determined the longitudinal kinetics of CRP levels on 78 RT-PCR-confirmed COVID-19 patients (49 non-severe and 29 severe cases) and 50 PCR-negative controls. Results: COVID-19 patients had overall significantly elevated CRP at baseline when compared to PCR-negative controls [median 11.1 (IQR: 2.0-127.8) mg/L vs. 0.9 (IQR: 0.5-1.9) mg/L; p=0.0004)]. Moreover, severe COVID-19 patients had significantly higher median CRP levels than non-severe cases [166.1 (IQR: 48.6-332.5) mg/L vs. 2.4 (IQR: 1.2-7.6) mg/L; p<0.00001)]. In addition, persistently elevated levels of CRP were exhibited among those with comorbidities and higher age groups. Area under receiver operating characteristic curve (AUC) analysis of CRP levels distinguished PCR-confirmed COVID-19 patients from the ones with PCR-negative non-COVID-19 individuals, with an AUC value of 0.77 (95% CI: 0.68-0.84; p=0.001). Moreover, it clearly distinguished severe from non-severe COVID-19 patients, with an AUC value of 0.83 (95% CI: 0.73-0.91). After adjusting for age and the presence of comorbidities, CRP levels above 30 mg/L were significantly associated with an increased risk of developing severe COVID-19 (adjusted relative risk 3.99 (95%CI: 1.35-11.82; p=0.013). Conclusions: Determining CRP levels in COVID-19 patients in African settings may provide a simple, prompt, and inexpensive assessment of the severity status at baseline and monitoring of treatment outcomes.Keywords: CRP, COVID-19, SARS-CoV-2, biomarker
Procedia PDF Downloads 82685 Comparison of Self-Efficacy and Life Satisfaction in Normal Users and Users with Internet Addiction
Authors: Mansour Abdi, Hadi Molaei Yasavoli
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The purpose of this research is to comparison of self- efficacy and life satisfaction in normal users and users with internet addiction. The present study was descriptive and causal-comparative. Therefore, 304 students were selected random sampling method from students of Semnan University and completed questionnaires of internet addiction (young), Self-Efficacy Questionnaire and Life Satisfaction (SWIS). For data analysis was used the Multivariate Analysis of Variance (MANOVA). The results showed that internet addiction users have lower levels of self-efficacy and life satisfaction in comparison with normal users and the difference in p=0/0005 significantly. The findings showed that 78 percent of the variance in the dependent variables of self-efficacy and life satisfaction by grouping variables (internet addiction users and normal) is determined. Finally, considering that the rate of self-efficacy and life satisfaction is effective in the incidence of Internet addiction, it is proposed required measures are taken to enhance self-efficacy and life satisfaction in Internet users.Keywords: self-efficacy, life satisfaction, users, internet addiction, normal users
Procedia PDF Downloads 491684 Hosoya Polynomials of Zero-Divisor Graphs
Authors: Abdul Jalil M. Khalaf, Esraa M. Kadhim
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The Hosoya polynomial of a graph G is a graphical invariant polynomial that its first derivative at x= 1 is equal to the Wiener index and second derivative at x=1 is equal to the Hyper-Wiener index. In this paper we study the Hosoya polynomial of zero-divisor graphs.Keywords: Hosoya polynomial, wiener index, Hyper-Wiener index, zero-divisor graphs
Procedia PDF Downloads 529683 Preliminary Seismic Hazard Mapping of Papua New Guinea
Authors: Hadi Ghasemi, Mark Leonard, Spiliopoulos Spiro, Phil Cummins, Mathew Moihoi, Felix Taranu, Eric Buri, Chris Mckee
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In this study the level of seismic hazard in terms of Peak Ground Acceleration (PGA) was calculated for return period of 475 years, using modeled seismic sources and assigned ground-motion equations. The calculations were performed for bedrock site conditions (Vs30=760 m/s). From the results it is evident that the seismic hazard reaches its maximum level (i.e. PGA≈1g for 475 yr return period) at the Huon Peninsula and southern New Britain regions. Disaggregation analysis revealed that moderate to large earthquakes occurring along the New Britain Trench mainly control the level of hazard at these locations. The open-source computer program OpenQuake developed by Global Earthquake Model foundation was used for the seismic hazard computations. It should be emphasized that the presented results are still preliminary and should not be interpreted as our final assessment of seismic hazard in PNG.Keywords: probabilistic seismic hazard assessment, Papua New Guinea, building code, OpenQuake
Procedia PDF Downloads 556682 The Role of Psychological Factors in Prediction Academic Performance of Students
Authors: Hadi Molaei, Yasavoli Davoud, Keshavarz, Mozhde Poordana
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The present study aimed was to prediction the academic performance based on academic motivation, self-efficacy and Resiliency in the students. The present study was descriptive and correlational. Population of the study consisted of all students in Arak schools in year 1393-94. For this purpose, the number of 304 schools students in Arak was selected using multi-stage cluster sampling. They all questionnaires, self-efficacy, Resiliency and academic motivation Questionnaire completed. Data were analyzed using Pearson correlation and multiple regressions. Pearson correlation showed academic motivation, self-efficacy, and Resiliency with academic performance had a positive and significant relationship. In addition, multiple regression analysis showed that the academic motivation, self-efficacy and Resiliency were predicted academic performance. Based on the findings could be conclude that in order to increase the academic performance and further progress of students must provide the ground to strengthen academic motivation, self-efficacy and Resiliency act on them.Keywords: academic motivation, self-efficacy, resiliency, academic performance
Procedia PDF Downloads 496681 IoT Based Agriculture Monitoring Framework for Sustainable Rice Production
Authors: Armanul Hoque Shaon, Md Baizid Mahmud, Askander Nobi, Md. Raju Ahmed, Md. Jiabul Hoque
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In the Internet of Things (IoT), devices are linked to the internet through a wireless network, allowing them to collect and transmit data without the need for a human operator. Agriculture relies heavily on wireless sensors, which are a vital component of the Internet of Things (IoT). This kind of wireless sensor network monitors physical or environmental variables like temperatures, sound, vibration, pressure, or motion without relying on a central location or sink and collaboratively passes its data across the network to be analyzed. As the primary source of plant nutrients, the soil is critical to the agricultural industry's continued growth. We're excited about the prospect of developing an Internet of Things (IoT) solution. To arrange the network, the sink node collects groundwater levels and sends them to the Gateway, which centralizes the data and forwards it to the sensor nodes. The sink node gathers soil moisture data, transmits the mean to the Gateways, and then forwards it to the website for dissemination. The web server is in charge of storing and presenting the moisture in the soil data to the web application's users. Soil characteristics may be collected using a networked method that we developed to improve rice production. Paddy land is running out as the population of our nation grows. The success of this project will be dependent on the appropriate use of the existing land base.Keywords: IoT based agriculture monitoring, intelligent irrigation, communicating network, rice production
Procedia PDF Downloads 153680 Analysis of Two-Phase Flow Instabilities in Conventional Channel of Nuclear Power Reactor
Authors: M. Abdur Rashid Sarkar, Riffat Mahmud
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Boiling heat transfer plays a crucial role in cooling nuclear reactor for safe electricity generation. A two phase flow is susceptible to thermal-hydrodynamic instabilities, which may cause flow oscillations of constant amplitude or diverging amplitude. These oscillations may induce boiling crisis, disturb control systems, or cause mechanical damage. Based on their mechanisms, various types of instabilities can be classified for a nuclear reactor. From a practical engineering point of view one of the major design difficulties in dealing with multiphase flow is that the mass, momentum, and energy transfer rates and processes may be quite sensitive to the geometric configuration of the heat transfer surface. Moreover, the flow within each phase or component will clearly depend on that geometric configuration. The complexity of this two-way coupling presents a major challenge in the study of multiphase flows and there is much that remains to be done. Yet, the parametric effects on flow instability such as the effect of aspect ratio, pressure drop, channel length, its orientation inlet subcooling and surface roughness etc. have been analyzed. Another frequently occurring instability, known as the Kelvin–Helmholtz instability has been briefly reviewed. Various analytical techniques for predicting parametric effect on the instability are analyzed in terms of their applicability and accuracy.Keywords: two phase flows, boiling crisis, thermal-hydrodynamic instabilities, water cooled nuclear reactors, kelvin–helmholtz instability
Procedia PDF Downloads 397679 Engineering Review of Recycled Concrete Production for Structural and Non-Structural Applications (Green Concrete)
Authors: Hadi Rouhi Belvirdi
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With the increasing demand for sustainable development, recycled materials are receiving more attention in construction projects. To promote sustainable development, this review article evaluates the feasibility of using recycled concrete in construction projects from an economic and environmental perspective. The results show that making concrete using recycled concrete is a suitable strategy for sustainable development. A complete examination of the physical and chemical properties of these recycled materials also provides important information about their suitability for use in the construction industry. Most of the studies do not show surprising results of the compressive or bending strength of these materials, and only the aspect of sustainable development of these materials is of interest. Their application can be investigated more in masonry and joinery works, but among them, some studies sometimes obtained more compressive and bending strength than the control sample, which can be used in concrete structures. Most of the cases introduced and discussed in this study can be implemented and help the country and the people of Iran preserve the environment and discuss sustainable development.Keywords: environmental recycling, sustainable development, recycled materials, construction management
Procedia PDF Downloads 27678 Diesel Engine Performance Optimization to Reduce Fuel Consumption and Emissions Issues
Authors: hadi kargar, bahador shabani
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In this article, 16 cylinder motor combustion CFD modeling with a diameter of 165 mm and 195 mm along the way to help the FIRE software to optimize its function to work. A three-dimensional model of the processes that formed inside the cylinder made that involves mixing the fuel and air, ignition and spraying. In this three-dimensional model, all chemical species, density of air fuel spraying and spray with full profile intended to detailed results from mixing the fuel and air, igniting the ignition advance, spray, and mixed media in different times and get fit by moving the piston. Optimal selection of the model for the shape of the piston and spraying fuel specifications (including the management of spraying, the number of azhneh hole, start time of spraying and spraying angle) to achieve the best fuel consumption and minimal pollution. The spray hole 6 and 7 in three different configurations with five spraying and gives the best geometry and various performances in the simulation. 6 hole spray angle, finally spraying 72.5 degrees and two forms of spraying a better performance in comparison with other items of their own.Keywords: spray, FIRE, CFD, optimize, diesel engine
Procedia PDF Downloads 419677 Political Corruption and Workplace Misconduct
Authors: Masako Darrough, Mahmud Hossain, Santanu Mitra
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The prevalent and increasing workplace misconduct in the United States presents a significant threat to social welfare. Despite efforts by enforcement agencies, U.S. workers remain vulnerable to employer exploitation, as evidenced by rising workplace injuries and discrimination lawsuits. While existing literature has identified several factors associated with unethical labor practices, the influence of political corruption remains largely unexplored. This paper aims to fill this gap by investigating the relationship between political corruption and workplace misconduct in the U.S. context. Using the data from the U.S. Bureau of Labor Statistics, the Equal Employment Opportunity Commission, and corruption convictions reported by the Department of Justice, we find a positive association between political corruption and workplace misconduct among U.S.-listed firms that are headquartered in different states from 2004 to 2022. Both unionization and stricter labor laws attenuate the positive association between corruption and unethical labor practices. Our analyses also address potential endogeneity concerns via difference-in-differences, instrumental variables, and propensity-score-matched analyses, reaffirming the robustness of our findings. This research contributes to the literature by shedding light on how corrupt political climates influence organizational operational behavior and unethical practices. It also underscores the importance of stakeholder trust and the role of regulatory frameworks and offers practical insights to policymakers by suggesting a judicious allocation of enforcement resources to more corrupt states.Keywords: workplace misconduct, political corruption, unionization, labor law strictness
Procedia PDF Downloads 22676 Mechanical Properties of Palm Oil-Based Resin Containing Unsaturated Polyester
Authors: Alireza Fakhari, Abdul Razak Rahmat
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In this study, new palm oil-based polymer systems have been produced by blending unsaturated polyester (UPE) and maleinated, acrylated epoxidized palm oil (MAEPO). The MAEPO/UPE ratio was varied between 10/90 and 40/60 wt%. The influences of various loadings of MAEPO (10, 20, 30, and 40 wt%) on tensile, flexural and impact properties of resulting polymer systems were investigated. The results revealed that, these bio-based polymer systems exhibit mechanical properties comparable to those of petroleum-based polymers.Keywords: palm oil, bio-based resin, renewable resources, unsaturated polyester resin
Procedia PDF Downloads 344675 Preparation of Sorbent Materials for the Removal of Hardness and Organic Pollutants from Water and Wastewater
Authors: Thanaa Abdel Moghny, Mohamed Keshawy, Mahmoud Fathy, Abdul-Raheim M. Abdul-Raheim, Khalid I. Kabel, Ahmed F. El-Kafrawy, Mahmoud Ahmed Mousa, Ahmed E. Awadallah
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Ecological pollution is of great concern for human health and the environment. Numerous organic and inorganic pollutants usually discharged into the water caused carcinogenic or toxic effect for human and different life form. In this respect, this work aims to treat water contaminated by organic and inorganic waste using sorbent based on polystyrene. Therefore, two different series of adsorbent material were prepared; the first one included the preparation of polymeric sorbent from the reaction of styrene acrylate ester and alkyl acrylate. The second series involved syntheses of composite ion exchange resins of waste polystyrene and amorphous carbon thin film (WPS/ACTF) by solvent evaporation using micro emulsion polymerization. The produced ACTF/WPS nanocomposite was sulfonated to produce cation exchange resins ACTF/WPSS nanocomposite. The sorbents of the first series were characterized using FTIR, 1H NMR, and gel permeation chromatography. The thermal properties of the cross-linked sorbents were investigated using thermogravimetric analysis, and the morphology was characterized by scanning electron microscope (SEM). The removal of organic pollutant was determined through absorption tests in a various organic solvent. The chemical and crystalline structure of nanocomposite of second series has been proven by studies of FTIR spectrum, X-rays, thermal analysis, SEM and TEM analysis to study morphology of resins and ACTF that assembled with polystyrene chain. It is found that the composite resins ACTF/WPSS are thermally stable and show higher chemical stability than ion exchange WPSS resins. The composite resin was evaluated for calcium hardness removal. The result is evident that the ACTF/WPSS composite has more prominent inorganic pollutant removal than WPSS resin. So, we recommend the using of nanocomposite resin as new potential applications for water treatment process.Keywords: nanocomposite, sorbent materials, waste water, waste polystyrene
Procedia PDF Downloads 429674 The Influence of Strengthening on the Fundamental Frequency and Stiffness of a Confined Masonry Wall with an Opening for а Door
Authors: Emin Z. Mahmud
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This paper presents the observations from a series of shaking-table tests done on a 1:1 scaled confined masonry wall model, with opening for a door – specimens CMDuS (confined masonry wall with opening for a door before strengthening) and CMDS (confined masonry wall with opening for a door after strengthening). Frequency and stiffness changes before and after GFRP (Glass Fiber Reinforced Plastic) wall strengthening are analyzed. Definition of dynamic properties of the models was the first step of the experimental testing, which enabled acquiring important information about the achieved stiffness (natural frequencies) of the model. The natural frequency was defined in the Y direction of the model by applying resonant frequency search tests. It is important to mention that both specimens CMDuS and CMDS are subjected to the same effects. The tests are realized in the laboratory of the Institute of Earthquake Engineering and Engineering Seismology (IZIIS), Skopje. The specimens were examined separately on the shaking table, with uniaxial, in-plane excitation. After testing, samples were strengthened with GFRP and re-tested. The initial frequency of the undamaged model CMDuS is 13.55 Hz, while at the end of the testing, the frequency decreased to 6.38 Hz. This emphasizes the reduction of the initial stiffness of the model due to damage, especially in the masonry and tie-beam to tie-column connection. After strengthening of the damaged wall, the natural frequency increases to 10.89 Hz. This highlights the beneficial effect of the strengthening. After completion of dynamic testing at CMDS, the natural frequency is reduced to 6.66 Hz.Keywords: behaviour of masonry structures, Eurocode, frequency, masonry, shaking table test, strengthening
Procedia PDF Downloads 130673 Neutronic Calculations for Central Test Loop in Heavy Water Research Reactor
Authors: Hadi Shamoradifar, Behzad Teimuri, Parviz Parvaresh, Saeed Mohammadi
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One of the experimental facilities of the heavy water research reactor is the central test loop (C.T.L). It is located along the central axial line of the vessel, and therefore will highly affect the neutronic parameters of the reactor, so from the neutronics point of view, C.T.L is the most important facility. It is mainly designed for fuel testing, thought other applications such as radioisotope production and neutron activation, can be imagine for it. All of the simulations were performed by MCNPX2.6. As a first step towards C.T.L analysis, the effect of D2O-filled, H2O-filled, and He-filled C.T.L on the effective multiplication factor (Keff.), have been evaluated. According to results, H2O-filled C.T.L has a higher thermal neutron, while He-filled C.T.L includes more resonance neutrons. In the next step thermal and total axial neutron fluxes, were calculated and used as the comparison parameters. The core without C.T.L (C.T.L replaced by heavy water) is selected as the reference case, and the effect of all other cases is calculated according to that.Keywords: heavy water reactor, neutronic calculations, central test loop, neutron activation
Procedia PDF Downloads 363672 Numerical Analysis of Fluid Mixing in Three Split and Recombine Micromixers at Different Inlets Volume Ratio
Authors: Vladimir Viktorov, M. Readul Mahmud, Carmen Visconte
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Numerical simulation were carried out to study the mixing of miscible liquid at different inlets volume ratio (1 to 3) within two existing mixers namely Chain, Tear-drop and one new “C-H” mixer. The new passive C-H micromixer is developed based on split and recombine principles, combining the operation concepts of known Chain mixer and H mixer. The mixing performances of the three micromixers were predicted by a preliminary numerical analysis of the flow patterns inside the channel in terms of the segregation or distribution of path lines. Afterward, the efficiency and the pressure drop were investigated numerically, taking into account species transport. All numerical calculations were computed at a wide range of Reynolds number from 1 to 100. Among the presented three micromixers, tear-drop provides fairly good efficiency except in the middle range of Re numbers but has high-pressure drop. In addition, inlets flow ratio has a significant influence on efficiency, especially at the Re number range of 10 to 50, Moreover maximum increase of efficiency is almost 10% when inlets flow ratio is increased by 1. Chain mixer presents relatively low mixing efficiency at low and middle range of Re numbers (5≤Re≤50) but has reasonable pressure drop. Furthermore, Chain mixer shows almost no dependence on inlets flow ratio. Whereas, C-H mixer poses excellent mixing efficiency (more than 93%) for all range of Re numbers and causes the lowest pressure drop, On top of that efficiency has slight dependency on inlets flow ratio. In addition, C-H mixer shows respectively about three and two times lower pressure drop than Tear-drop and Chain mixers.Keywords: CFD, micromixing, passive micromixer, SAR
Procedia PDF Downloads 482671 Predict Suspended Sediment Concentration Using Artificial Neural Networks Technique: Case Study Oued El Abiod Watershed, Algeria
Authors: Adel Bougamouza, Boualam Remini, Abd El Hadi Ammari, Feteh Sakhraoui
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The assessment of sediments being carried by a river is importance for planning and designing of various water resources projects. In this study, Artificial Neural Network Techniques are used to estimate the daily suspended sediment concentration for the corresponding daily discharge flow in the upstream of Foum El Gherza dam, Biskra, Algeria. The FFNN, GRNN, and RBNN models are established for estimating current suspended sediment values. Some statistics involving RMSE and R2 were used to evaluate the performance of applied models. The comparison of three AI models showed that the RBNN model performed better than the FFNN and GRNN models with R2 = 0.967 and RMSE= 5.313 mg/l. Therefore, the ANN model had capability to improve nonlinear relationships between discharge flow and suspended sediment with reasonable precision.Keywords: artificial neural network, Oued Abiod watershed, feedforward network, generalized regression network, radial basis network, sediment concentration
Procedia PDF Downloads 418670 The Influence of Strengthening on the Fundamental Frequency and Stiffness of a Confined Masonry Wall with an Opening for а Window
Authors: Emin Z. Mahmud
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Shaking table tests are planned in order to deepen the understanding of the behavior of confined masonry structures with or without openings. The tests are realized in the laboratory of the Institute of Earthquake Engineering and Engineering Seismology (IZIIS) – Skopje. The specimens were examined separately on the shaking table, with uniaxial, in-plane excitation. After testing, samples were strengthened with GFRP (Glass Fiber Reinforced Plastic) and re-tested. This paper presents the observations from a series of shaking-table tests done on a 1:1 scaled confined masonry wall model, with opening for a window – specimens CMWuS (before strengthening) and CMWS (after strengthening). Frequency and stiffness changes before and after GFRP wall strengthening are analyzed. Definition of dynamic properties of the models was the first step of the experimental testing, which enabled acquiring important information about the achieved stiffness (natural frequencies) of the model. The natural frequency was defined in the Y direction of the model by applying resonant frequency search tests. It is important to mention that both specimens CMWuS and CMWS are subjected to the same effects. The initial frequency of the undamaged model CMWuS is 18.79 Hz, while at the end of the testing, the frequency decreased to 12.96 Hz. This emphasizes the reduction of the initial stiffness of the model due to damage, especially in the masonry and tie-beam to tie-column connection. After strengthening the damaged wall, the natural frequency increases to 14.67 Hz. This highlights the beneficial effect of strengthening. After completion of dynamic testing at CMWS, the natural frequency is reduced to 10.75 Hz.Keywords: behaviour of masonry structures, Eurocode, frequency, masonry, shaking table test, strengthening
Procedia PDF Downloads 118669 Using Electro-Biogrouting to Stabilize of Soft Soil
Authors: Hamed A. Keykha, Hadi Miri
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This paper describes a new method of soil stabilisation, electro-biogrouting (EBM), for improvement of soft soil with low hydraulic conductivity. This method uses an applied voltage gradient across the soil to induce the ions and bacteria cells through the soil matrix, resulting in CaCO3 precipitation and an increase of the soil shear strength in the process. The EBM were used effectively with two injection methods; bacteria injection and products of bacteria injection. The bacteria cells, calcium ions and urea were moved across the soil by electromigration and electro osmotic flow respectively. The products of bacteria (CO3-2) were moved by electromigration. The results showed that the undrained shear strength of the soil increased from 6 to 65 and 70 kPa for first and second injection method respectively. The injection of carbonate solution and calcium could be effectively flowed in the clay soil compare to injection of bacteria cells. The detection of CaCO3 percentage and its corresponding water content across the specimen showed that the increase of undrained shear strength relates to the deposit of calcite crystals between soil particles.Keywords: Sporosarcina pasteurii, electrophoresis, electromigration, electroosmosis, biocement
Procedia PDF Downloads 528