Search results for: Abubakar Sadeeq Mohammed
639 Residual Modulus of Elasticity of Self-Compacting Concrete Incorporated Unprocessed Waste Fly Ash after Expose to the Elevated Temperature
Authors: Mohammed Abed, Rita Nemes, Salem Nehme
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The present study experimentally investigated the impact of incorporating unprocessed waste fly ash (UWFA) on the residual mechanical properties of self-compacting concrete (SCC) after exposure to elevated temperature. Three mixtures of SCC have been produced by replacing the cement mass by 0%, 15% and 30% of UWFA. Generally, the fire resistance of SCC has been enhanced by replacing the cement up to 15% of UWFA, especially in case of residual modulus of elasticity which considers more sensitive than other mechanical properties at elevated temperature. However, a strong linear relationship has been observed between the residual flexural strength and modulus of elasticity, where both of them affected significantly by the cracks appearance and propagation as a result of elevated temperature. Sustainable products could be produced by incorporating unprocessed waste powder materials in the production of concrete, where the waste materials, CO2 emissions, and the energy needed for processing are reduced.Keywords: self-compacting high-performance concrete, unprocessed waste fly ash, fire resistance, residual modulus of elasticity
Procedia PDF Downloads 128638 Nutrient Availability in River Ecosystems Follows Human Activities More than Climate Warming
Authors: Mohammed Abdulridha Hamdan
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To face the water crisis, understanding the role of human activities on nutrient concentrations in aquatic ecosystems needs more investigations compare to extensively studies which have been carried out to understand these impacts on water quality of different aquatic ecosystems. We hypothesized human activates on the catchments of Tigris river may change nutrient concentrations in water along the river. The results showed that phosphate concentration differed significantly among the studied sites due to distributed human activities, while nitrate concentration did not. Phosphate and nitrate concentrations were not affected by water temperature. We concluded that human activities on the surrounding landscapes could be more essential sources for nutrients of aquatic ecosystems than role of ongoing climate warming. Despite the role of warming in driving nutrients availability in aquatic ecosystems, our findings suggest to take the different activities on the surrounding catchments into account in the studies caring about trophic status classification of aquatic ecosystems.Keywords: phosphate, nitrate, anthropogenic, warming
Procedia PDF Downloads 99637 Nutrient Availability in River Ecosystems Follows Human Activities More than Climate Warming
Authors: Mohammed Abdulridha Hamdan
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To face the water crisis, understanding the role of human activities on nutrient concentrations in aquatic ecosystems needs more investigations compare to extensively studies, which have been carried out to understand these impacts on water quality of different aquatic ecosystems. We hypothesized human activates on the catchments of Tigris river may change nutrient concentrations in water along the river. The results showed that phosphate concentration differed significantly among the studied sites due to distributed human activities, while nitrate concentration did not. Phosphate and nitrate concentrations were not affected by water temperature. We concluded that human activities on the surrounding landscapes could be more essential sources for nutrients of aquatic ecosystems than role of ongoing climate warming. Despite the role of warming in driving nutrients availability in aquatic ecosystems, our findings suggest to take the different activities on the surrounding catchments into account in the studies caring about trophic status classification of aquatic ecosystems.Keywords: phosphate, nitrate, Anthropogenic, warming
Procedia PDF Downloads 80636 Investigation of Specific Wear Rate of Austenitic and Duplex Stainless Steel Alloys in High Temperatures
Authors: Dler Abdullah Ahmed, Zozan Ahmed Mohammed
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Wear as an unavoidable phenomenon in stainless steel contact sliding parts is investigated In this work. Two grades of austenitic AISI 304, and S31254, as well as duplexes of S32205, and AISI 2507, were chosen to compare their wear behavior in temperatures ranging from room temperature to 550°C. The experimental results show that AISI 304 austenitic and AISI 2205 duplex stainless steel had lower wear resistance compared with S31254 and AISI 2507 in various temperatures. When the temperature rose to 140°C, and the wear rate of all grades increased, AISI 304 had the highest at 7.028x10-4 mm3/Nm, and AISI 2507 had the lowest at 4.9033 x 10-4 mm3/Nm. At 300°C, the oxides began to form on the worn surfaces, causing the wear rate to slow. As a result, when temperatures exceeded 300°C, the specific wear rate decreased significantly in all specimens. According to the XRD patterns, the main types of oxides formed on worn surfaces were magnetite, hematite, and chromite.Keywords: wear, stainless steel, temperature, groove, oxide
Procedia PDF Downloads 59635 Investigation of Specific Wear Rate of Austenitic and Duplex Stainless Steel Alloys in High Temperatures
Authors: Dler Abdullah Ahmed, Zozan Ahmed Mohammed
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Wear as an unavoidable phenomenon in stainless steel contact sliding parts is investigated In this work. Two grades of austenitic AISI 304, and S31254, as well as duplexes of S32205, and AISI 2507, were chosen to compare their wear behavior in temperatures ranging from room temperature to 550°C. The experimental results show that AISI 304 austenitic and AISI 2205 duplex stainless steel had lower wear resistance compared with S31254 and AISI 2507 in various temperatures. When the temperature rose to 140°C, and the wear rate of all grades increased, AISI 304 had the highest at 7.028x10-4 mm3/Nm, and AISI 2507 had the lowest at 4.9033 x 10-4 mm3/Nm. At 300°C, the oxides began to form on the worn surfaces, causing the wear rate to slow. As a result, when temperatures exceeded 300°C, the specific wear rate decreased significantly in all specimens. According to the XRD patterns, the main types of oxides formed on worn surfaces were magnetite, hematite, and chromite.Keywords: wear, stainless steel, temperature, groove, oxide
Procedia PDF Downloads 54634 Issues in Translating Hadith Terminologies into English: A Critical Approach
Authors: Mohammed Riyas Pp
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This study aimed at investigating major issues in translating the Arabic Hadith terminologies into English, focusing on choosing the most appropriate translation for each, reviewing major Hadith works in English. This study is confined to twenty terminologies with regard to classification of Hadith based on authority, strength, number of transmitters and connections in Isnad. Almost all available translations are collected and analyzed to find the most proper translation based on linguistic and translational values. To the researcher, many translations lack precise understanding of either Hadith terminologies or English language and varieties of methodologies have influence on varieties of translations. This study provides a classification of translational and conceptual issues. Translational issues are related to translatability of these terminologies and their equivalence. Conceptual issues provide a list of misunderstandings due to wrong translations of terminologies. This study ends with a suggestion for unification in translating terminologies based on convention of Muslim scholars having good understanding of Hadith terminologies and English language.Keywords: english language, hadith terminologies, equivalence in translation, problems in translation
Procedia PDF Downloads 179633 Seismic Response and Sensitivity Analysis of Circular Shallow Tunnels
Authors: Siti Khadijah Che Osmi, Mohammed Ahmad Syed
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Underground tunnels are one of the most popular public facilities for various applications such as transportation, water transfer, network utilities and etc. Experience from the past earthquake reveals that the underground tunnels also become vulnerable components and may damage at certain percentage depending on the level of ground shaking and induced phenomena. In this paper a numerical analysis is conducted in evaluating the sensitivity of two types of circular shallow tunnel lining models to wide ranging changes in the geotechnical design parameter. Critical analysis has been presented about the current methods of analysis, structural typology, ground motion characteristics, effect of soil conditions and associated uncertainties on the tunnel integrity. The response of the tunnel is evaluated through 2D non-linear finite element analysis, which critically assesses the impact of increasing levels of seismic loads. The finding from this study offer significant information on improving methods to assess the vulnerability of underground structures.Keywords: geotechnical design parameter, seismic response, sensitivity analysis, shallow tunnel
Procedia PDF Downloads 435632 Assessment and Evaluation of Football Performance
Authors: Bulus Kpame, Mukhtar Mohammed Alhaji, Garba Jibril
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In any team sport, the most important variables that should be used to measure performance are physical condition, and technical and tactical performance. In a complex game like football, it is extremely difficult to measure the relative importance of each of these variables. However, physical fitness itself has been shown to consist of several components, like endurance, strength, flexibility, agility, coordination and speed. Each of these components has been shown to consist of several subcomponents. This paper attempts to describe a test battery to assess and evaluate physical performance in football players. This battery comprises a functional, structured training session of about 2.5hrs. it consists of quality rating of the warm-up procedure, tests of flexibility, football skills, power, speed, and endurance. Acceptable values for performance in each of the tests are also presented under each test. It is hoped that this battery of tests will be helpful to the coach in determining the effect of a specific training program. It would also be helpful to train physician and trainer, to monitor progress during rehabilitation after sustaining any injury.Keywords: assessment, evaluation, performance, programs
Procedia PDF Downloads 397631 Optimization of Friction Stir Spot Welding Process Parameters for Joining 6061 Aluminum Alloy Using Taguchi Method
Authors: Mohammed A. Tashkandi, Jawdat A. Al-Jarrah, Masoud Ibrahim
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This paper investigates the shear strength of the joints produced by friction stir spot welding process (FSSW). FSSW parameters such as tool rotational speed, plunge depth, shoulder diameter of the welding tool and dwell time play the major role in determining the shear strength of the joints. The effect of these four parameters on FSSW process as well as the shear strength of the welded joints was studied via five levels of each parameter. Taguchi method was used to minimize the number of experiments required to determine the fracture load of the friction stir spot-welded joints by incorporating independently controllable FSSW parameters. Taguchi analysis was applied to optimize the FSSW parameters to attain the maximum shear strength of the spot weld for this type of aluminum alloy.Keywords: Friction Stir Spot Welding, Al6061 alloy, Shear Strength, FSSW process parameters
Procedia PDF Downloads 420630 The Search of New Laws for a Gluten Kingdom
Authors: Mohammed Saleem Tariq
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The enthusiasm for gluten avoidance in a growing market is met by improvements in sensitive detection methods for analysing gluten content. Paradoxically, manufacturers employ no such systems in the production process but continue to market their product as gluten free, a significant risk posed to an undetermined coeliac population. The paper resonates with an immunological response that causes gastrointestinal scarring and villous atrophy with the conventional description of personal injury. The current developing regime in the UK however, it is discussed, has avoided creating specific rules to provide an adequate level of protection for this type of vulnerable ‘characteristic’. Due to the struggle involved with identifying an appropriate cause of action, this paper analyses whether a claim brought in misrepresentation, negligence and/or under the Consumer Protect Act 1987 could be sustained. A necessary comparison is then made with the approach adopted by the Americans with Disability Act 1990 which recognises this chronic disease as a disability. The ongoing failure to introduce a level of protection which matches that afforded to those who fall into any one of the ‘protected characteristics’ under the Equality Act 2010, is inconceivable given the outstanding level of legal vulnerability.Keywords: coeliac, litigation, misrepresentation, negligence
Procedia PDF Downloads 356629 Performance of Self-Compacting Mortars Containing Foam Glass Granulate
Authors: Brahim Safi, Djamila Aboutaleb, Mohammed Saidi, Abdelbaki Benmounah, Fahima Benbrahim
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The inorganic wastes are currently used in the manufacture of concretes as mineral additions by cement substitution or as fine/coarse aggregates by replacing traditional aggregates. In this respect, this study aims to valorize the mineral wastes in particular glass wastes to produce granulated foam glass (as fine aggregates). Granulated foam glasses (GFG) were prepared from the glass powder (glass cullet) and foaming agent (limestone) according to applied manufacturing of GFG (at a heat treatment 850 ° C for 20min). After, self-compacting mortars were elaborated with fine aggregate (sand) and other variant mortars with granulated foam glass at volume ratio (0, 30, 50 and 100 %). Rheological characterization tests (fluidity) and physic-mechanical (density, porosity /absorption of water and mechanical tests) were carried out on studied mortars. The results obtained show that a slightly decreasing of compressive strength of mortars having lightness very important for building construction.Keywords: glass wastes, lightweight aggregate, mortar, fluidity, density, mechanical strength
Procedia PDF Downloads 225628 Morphometrics Study of Apis florea and Apis mellifera from Different Locations in Sudan
Authors: Mohammed M. Ibrahim, A. A. Yusuf, Manuel Du, Fiona Mumoki
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The traditional honey bee species of Sudan is Apis mellifera, but in 1985, the dwarf bee Apis florea was introduced to the country, so now there are two species present. However, there are conflicting assessments regarding the subspecies of Apis mellifera colonies in Sudan. Likewise, it is unclear if, in the 40 years since its introduction, Apis florea has already developed regional differences or ecotypes. To shed light on these questions, we performed a morphology study on Sudanese honeybees. Samples of 10 to 20 honeybee workers per colony of the two species were collected from 16 locations, spanning different climatic zones in Sudan during 2021. Measurements were taken from 16 morphometric characteristics using a stereo-microscope equipped with an Image Analysis System (Moticam Image Plus 5.0 Digital Microscope Camera) to study their variability. The results indicate that in both species, the general means of various characters showed significant differences (p < 0.05) within a species between different locations, indicating that there might indeed be regional differences. However, more taxonomic investigation and, ideally also, molecular studies are needed in order to confirm the proper identification of subspecies and their ecotypes.Keywords: Apis, subspecies, morphology, Sudan
Procedia PDF Downloads 94627 Analyses and Optimization of Physical and Mechanical Properties of Direct Recycled Aluminium Alloy (AA6061) Wastes by ANOVA Approach
Authors: Mohammed H. Rady, Mohd Sukri Mustapa, S Shamsudin, M. A. Lajis, A. Wagiman
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The present study is aimed at investigating microhardness and density of aluminium alloy chips when subjected to various settings of preheating temperature and preheating time. Three values of preheating temperature were taken as 450 °C, 500 °C, and 550 °C. On the other hand, three values of preheating time were chosen (1, 2, 3) hours. The influences of the process parameters (preheating temperature and time) were analyzed using Design of Experiments (DOE) approach whereby full factorial design with center point analysis was adopted. The total runs were 11 and they comprise of two factors of full factorial design with 3 center points. The responses were microhardness and density. The results showed that the density and microhardness increased with decreasing the preheating temperature. The results also found that the preheating temperature is more important to be controlled rather than the preheating time in microhardness analysis while both the preheating temperature and preheating time are important in density analysis. It can be concluded that setting temperature at 450 °C for 1 hour resulted in the optimum responses.Keywords: AA6061, density, DOE, hot extrusion, microhardness
Procedia PDF Downloads 344626 Evaluation of Longitudinal and Hoop Stresses and a Critical Study of Factor of Safety (FoS) in Design of a Glass-Fiber Pressure Vessel
Authors: Zainul Huda, Mohammed Hani Ajani
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The design, manufacture, and operation of thin-walled pressure vessels must be based on maximum safe operating pressure and an adequate factor of safety (FoS). This research paper first reports experimental evaluation of longitudinal and hoops stresses based on working pressure as well as maximum pressure; and then includes a critical study of factor of safety (FoS) in the design of a glass fiber pressure vessel. Experimental work involved the use of measuring instruments and the readings from pressure gauges. Design calculations involved the computations of design stress and FoS; the latter was based on breaking strength of 55 MPa for the glass fiber (pressure-vessel material). The experimentally determined FoS value has been critically compared with the general FoS allowed in the design of glass fiber pressure vessels.Keywords: thin-walled pressure vessel, hoop stress, longitudinal stress, factor of safety (FoS), fiberglass
Procedia PDF Downloads 476625 Evaluation of Erosive Wear Resistance of Commercial Hard Coatings with Plasma Nitride and Without Plasma Nitride in Aluminium Die Casting
Authors: A. Mohammed, R. Lewis, M. Marshall
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Commonly used coatings to protect tools in die casting were used. A heat treatment and then surface coating can have a large effect on erosion damage. Samples have been tested to evaluate their resistances to erosive wear and to assess how this compares with behaviour seen for untreated material. Five commercial (PN + TiN), (PN + TiAlCN), (TiN X 2), (TiN), and (TiAlCN) coatings have been evaluated for their wear resistance. The objective was to permit an optimized selection of coatings to be used to give good resistance to erosive wear. A test-Rig has been developed to study the erosive wear in aluminium die casting and provide an environment similar to industrial operation that is more practical than using actual machines. These surfaces were analysed using a Scanning Electron Microscope (SEM) and Optical Microscopes each with a different level of resolution. Examination of coating materials revealed an important parameter associated with the failure of the coating materials.This was adhesion of the coating material to the substrate surface. A well-adhered coating withstands wear much better compared to the poorest-adhering coating.Keywords: solid particle erosion, PVD-coatings, steel, erosion testing
Procedia PDF Downloads 233624 Evaluating the Possibility of Expanding National Health Insurance Funding From Zakat, Sudan
Authors: Fawzia Mohammed Idris
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Zakat is an Islamic procedure for wealth distribution as a social protection mechanism for needy people. This study aimed to assess the possibility to expand the share of fund for national health insurance fund from zakat funds allocated for poor people by measuring the reduction of poverty that result from the investing on direct payment to the needy or by covering them in social health insurance. This study used stata regression as a statistical analysis tool and the finding clarified that there is no significant relationship between the poverty rate as the main indicator and, the number of poor people covered by national health insurance on one hand and the number of benefits poor people from the distribution of zakat fund. This study experienced many difficulties regarding the quality and the consistency of the data. The study suggested that a joint mission between national health insurance fund and zakat chamber to conduct study to assess the efficient use of zakat fund allocated to poor people.Keywords: health finance, poverty, social health insurance, zakat
Procedia PDF Downloads 138623 Learning Resources as Determinants for Improving Teaching and Learning Process in Nigerian Universities
Authors: Abdulmutallib U. Baraya, Aishatu M. Chadi, Zainab A. Aliyu, Agatha Samson
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Learning Resources is the field of study that investigates the process of analyzing, designing, developing, implementing, and evaluating learning materials, learners, and the learning process in order to improve teaching and learning in university-level education essential for empowering students and various sectors of Nigeria’s economy to succeed in a fast-changing global economy. Innovation in the information age of the 21st century is the use of educational technologies in the classroom for instructional delivery, it involves the use of appropriate educational technologies like smart boards, computers, projectors and other projected materials to facilitate learning and improve performance. The study examined learning resources as determinants for improving the teaching and learning process in Abubakar Tafawa Balewa University (ATBU), Bauchi, Bauchi state of Nigeria. Three objectives, three research questions and three null hypotheses guided the study. The study adopted a Survey research design. The population of the study was 880 lecturers. A sample of 260 was obtained using the research advisor table for determining sampling, and 250 from the sample was proportionately selected from the seven faculties. The instrument used for data collection was a structured questionnaire. The instrument was subjected to validation by two experts. The reliability of the instrument stood at 0.81, which is reliable. The researchers, assisted by six research assistants, distributed and collected the questionnaire with a 75% return rate. Data were analyzed using mean and standard deviation to answer the research questions, whereas simple linear regression was used to test the null hypotheses at a 0.05 level of significance. The findings revealed that physical facilities and digital technology tools significantly improved the teaching and learning process. Also, consumables, supplies and equipment do not significantly improve the teaching and learning process in the faculties. It was recommended that lecturers in the various faculties should strengthen and sustain the use of digital technology tools, and there is a need to strive and continue to properly maintain the available physical facilities. Also, the university management should, as a matter of priority, continue to adequately fund and upgrade equipment, consumables and supplies frequently to enhance the effectiveness of the teaching and learning process.Keywords: education, facilities, learning-resources, technology-tools
Procedia PDF Downloads 10622 Facile Synthesis of Novel Substituted Aryl-Thiazole (SAT) Analogs via One-Pot Multicomponent Reaction as Potent Cytotoxic Agents against Cancer Cell Lines
Authors: Salma Mirza, Syeda Asma Naqvi, Khalid Mohammed Khan, M. Iqbal Choudhary
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In this study twenty-five (25) newly synthesized compounds substituted aryl thiazoles (SAT) 1-25 were synthesized, and in vitro cytotoxicity of these compounds was evaluated against four cancer cell lines namely, MCF-7 (ER+ve breast), MDA-MB-231 (ER-ve breast), HCT116 (colorectal), and, HeLa (cervical) and compared with the standard anticancer drug doxorubicin with IC50 value of 1.56 ± 0.05 μM. Among them, compounds 1, 4-8 and 19 were found to be active against all four cell lines. Compound 20 was found to be selectively active against MCF7 cells with IC50 value of 40.21 ± 4.15 µM, whereas compound 19 was active against only MCF7 and HeLa cells with IC50 values of 46.72 ± 1.8 and 19.86 ± 0.11 μM, respectively. These results suggest that aryl thiazoles 1 and 4 deserve to be investigated further in vivo as anti-cancer agents.Keywords: anticancer agents, breast cancer cell lines (MCF7, MDA-MB-231), colorectal cancer cell line (HCT-116), cervical cancer cell line (HeLa), Thiazole derivatives
Procedia PDF Downloads 291621 Investigation of Steady State Infiltration Rate for Different Head Condition
Authors: Nour Aljafari, Mariam, S. Maani, Serter Atabay, Tarig Ali, Said Daker, Lara Daher, Hamad Bukhammas, Mohammed Abou Shakra
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This paper aims at determining the soil characteristics that influence the irrigation process of green landscapes and deciding on the optimum amount of water needed for irrigation. The laboratory experiments were conducted using the constant head methodology to determine the soil infiltration rates. The steady state infiltration rate was reached after 10 minutes of infiltration at a rate of 200 mm/hr. The effects of different water heads on infiltration rates were also investigated, and the head of 11 cm was found to be the optimum head for the test. The experimental results showed consistent infiltration results for the range between 11 cm and 15 cm. The study also involved finding the initial moisture content, which ranged between 5% and 25%, and finding the organic content, which occupied 1% to 2% of the soil. These results will be later utilized, using the water balance approach, to estimate the optimum amount of water needed for irrigation for changing weather conditions.Keywords: infiltration rate, moisture content, grass type, organic content
Procedia PDF Downloads 289620 Motives and Barriers of Using Airbnb: Findings from Mixed Method Approach
Authors: Ghada Mohammed, Mohamed Abdel Salam, Passent Tantawi
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The study aimed to investigate the impact of motives and barriers for Egyptian users to use Airbnb as a platform of peer-to-peer accommodation instead of hotels on overall attitude towards Airbnb. A sequential mixed-methods approach was adopted to this study and it proposed a comprehensive research model adapted from both literature and results of qualitative phase and then tested via an online questionnaire. The findings revealed that, motives, price, home benefits, privacy, and online reviews significantly explained overall attitude towards Airbnb, while the main barriers were respectively: perceived risk and distrust in which they can predict the overall attitude. While from the subjective norms, only social influence can predict behavioral intention to use Airbnb. The study may serve as a practical reference for practitioners as well as researchers when developing programs and strategies to manage Airbnb consumers' needs and decision process. Some of the main conclusions drawn from this study are that variety was one of the major things that users like about Airbnb and the most important motives are the functional ones like price rather than the experiential ones like authenticity.Keywords: airbnb, barriers, disruptive innovation, motives, sharing economy
Procedia PDF Downloads 138619 Mechanical Properties of ECAP-Biomedical Titanium Materials: A Review
Authors: Mohsin Talib Mohammed, Zahid A. Khan, Arshad N. Siddiquee
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The wide use of titanium (Ti) materials in medicine gives impetus to a search for development new techniques with elevated properties such as strength, corrosion resistance and Young's modulus close to that of bone tissue. This article presents the most recent state of the art on the use of equal channel angular pressing (ECAP) technique in evolving mechanical characteristics of the ultrafine-grained bio-grade Ti materials. Over past few decades, research activities in this area have grown enormously and have produced interesting results, including achieving the combination of conflicting properties that are desirable for biomedical applications by severe plastic deformation (SPD) processing. A comprehensive review of the most recent work in this area is systematically presented. The challenges in processing ultrafine-grained Ti materials are identified and discussed. An overview of the biomedical Ti alloys processed with ECAP technique is given in this review, along with a summary of their effect on the important mechanical properties that can be achieved by SPD processing. The paper also offers insights in the mechanisms underlying SPD.Keywords: mechanical properties, ECAP, titanium, biomedical applications
Procedia PDF Downloads 447618 Enhancement in the Absorption Efficiency of GaAs/InAs Nanowire Solar Cells through a Decrease in Light Reflection
Authors: Latef M. Ali, Farah A. Abed, Zheen L. Mohammed
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In this paper, the effect of the Barium fluoride (BaF2) layer on the absorption efficiency of GaAs/InAs nanowire solar cells was investigated using the finite difference time domain (FDTD) method. By inserting the BaF2 as antireflection with the dominant size of 10 nm to fill the space between the shells of wires on the Si (111) substrate. The absorption is significantly improved due to the strong reabsorption of light reflected at the shells and compared with the reference cells. The present simulation leads to a higher absorption efficiency (Qabs) and reaches a value of 97%, and the external quantum efficiencies (EQEs) above 92% are observed. The current density (Jsc) increases by 0.22 mA/cm2 and the open-circuit voltage (Voc) is enhanced by 0.11 mV. it explore the design and optimization of high-efficiency solar cells on low-reflective absorption efficiency of GaAs/InAs using simulation software tool. The changes in the core and shell diameters profoundly affects the generation and recombination process, thus affecting the conversion efficiency of solar cells.Keywords: nanowire solar cells, absorption efficiency, photovoltaic, band structures, FDTD simulation
Procedia PDF Downloads 40617 Microbial Quality of Beef and Mutton in Bauchi Metropolis
Authors: Abdullahi Mohammed
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The microbial quality of beef and mutton sold in four major markets of Bauchi metropolis was assessed in order to assist in ascertaining safety. Shops were selected from 'Muda Lawal', 'Yelwa', 'Wunti', and 'Gwallameji' markets. The total bacterial count was used as index of quality. A total of thirty two (32) samples were collected in two successive visits. The samples were packed and labelled in a sterile polythene bags for transportation to the laboratory. Microbial analysis was carried out immediately upon arrival under a septic condition, where aerobic plate was used in determining the microbial load. Result showed that beef and mutton from Gwallameji had the highest bacterial count of 9.065 X 105 cfu/ml and 8.325 X 105 cfu/ml for beef and mutton respectively followed by Wunti market (6.95 X 105 beef and 4.838 X 105 motton) and Muda Lawal (4.86 X 105 cfu/ml beef and 5.998 X 105 cfu/ml mutton). Yelwa had 5.175 X 105 and 5.30 X 105 for beef and mutton respectively. Bacterial species isolated from the samples were Escherichia coli, Salmonella spp, Streptococcus species and Staphylococcus species. However, results obtained from all markets showed that there was no significant differences between beef and mutton in terms of microbial quality.Keywords: beef, mutton, salmonella, sterile
Procedia PDF Downloads 449616 SA-SPKC: Secure and Efficient Aggregation Scheme for Wireless Sensor Networks Using Stateful Public Key Cryptography
Authors: Merad Boudia Omar Rafik, Feham Mohammed
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Data aggregation in wireless sensor networks (WSNs) provides a great reduction of energy consumption. The limited resources of sensor nodes make the choice of an encryption algorithm very important for providing security for data aggregation. Asymmetric cryptography involves large ciphertexts and heavy computations but solves, on the other hand, the problem of key distribution of symmetric one. The latter provides smaller ciphertexts and speed computations. Also, the recent researches have shown that achieving the end-to-end confidentiality and the end-to-end integrity at the same is a challenging task. In this paper, we propose (SA-SPKC), a novel security protocol which addresses both security services for WSNs, and where only the base station can verify the individual data and identify the malicious node. Our scheme is based on stateful public key encryption (StPKE). The latter combines the best features of both kinds of encryption along with state in order to reduce the computation overhead. Our analysisKeywords: secure data aggregation, wireless sensor networks, elliptic curve cryptography, homomorphic encryption
Procedia PDF Downloads 286615 Formulation and Physico-Mechanical Characterization of a Self-Compacting Concrete Containing Seashells as an Addition Material
Authors: Brahim Safi, Mohammed Saidi, A. Benmounah, Jozef Mitterpach
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The aim of this work is to study the rheological and physico-mechanical properties of a self-compacting concrete elaborated with sea shells as an addition cementitious (total replacement of limestone fillers) and sand (partial and total substitution fine aggregate). Also, this present study is registered in the context of sustainable development by using this waste type which caused environmental problems. After preparation the crushed shells (obtaining fine aggregate) and finely crushed shells (obtaining end powder), concretes were manufactured using these two products. Rheological characterization tests (fluidity, filling capacity and segregation) and physico-mechanical properties (density and strength) were carried on these concretes. The results obtained show that it can be used as fin addition (by total replacement of limestone) or also used as sand by total substitution of natural sand.Keywords: seashells, limestone, sand, self-compacting concrete, fluidity, compressive strength, flexural strength
Procedia PDF Downloads 268614 Anti Corruption Conventions in Nigeria: Legal and Administrative Challenges
Authors: Mohammed Albakariyu Kabir
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There is a trend in development discourse to understand and explain the level of corruption in Nigeria, its anti-corruption crusade and why it is failing, as well as its level of compliance with International standards of United Nations Convention against Corruption (UNCAC) & African Union Convention on Converting and Preventing Corruption) to which Nigeria is a signatory. This paper discusses the legal and Constitutional provisions relating to corrupt practices and safeguards in Nigeria, as well as the obstacles to the implementation of these Conventions.The paper highlights the challenges posed to the Anti-Corruption crusade by analysing the loopholes that exist both in administrative structure and in scope of the relevant laws. The paper argues that Nigerian Constitution did not make adequate provisions for the implementation of the conventions, hence a proposal which will ensure adequate provision for implementing the conventions to better the lives of Nigerians. The paper concludes that there is the need to build institutional parameters, adequate constitutional and structural safeguards, as well as to synergise strategies, collaborations and alliances to facilitate the timely domestication and implementation of the conventions.Keywords: anti-corruption, corruption, convention, domestication, poverty, state parties
Procedia PDF Downloads 438613 Effects of the Gap on the Cooling Performance of Microchannels Heat Sink
Authors: Mohammed W. Sulaiman, Chi-Chuan Wang
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Due to the improved performance of electronic systems, the demand for electronic cooling devices with high heat dissipation has increased. This research evaluates plain microchannel cold plates with a gap above the microchannels. The present study examines the effect of the gap above straight fin microchannels in the cold plate using the dielectric Novec 7000 as a working fluid. The experiments compared two transparency cover with the same geometry and dimension for the test section. One has a gap above the microchannels (GAM) 1/3 of fin height, and another one with no gap above the microchannels (NGAM); the mass flux ranges from 25 to 260 kg/m2s, while the heat flux spans from 50 to 150 W/cm2. The results show quite an improvement in performance with this space gap above the microchannels. The test results showed that the design of the GAM shows a superior heat transfer coefficient (HTC), up 90% than that of NCBM. The GAM design has a much lower pressure drop by about 7~24% compared to the NGAM design at different mass flux and heat flux at the fully liquid inlet. The proposed space gap of 0.33% of fin height above the microchannels enables the surface temperature to decrease by around 3~7 °C compared to no gap above the microchannels, especially at high heat fluxes.Keywords: microchannels, pressure drop, enhanced performance, electronic cooling, gap
Procedia PDF Downloads 65612 A Systematic Review in the Impacts of Skilled Parent Migration on Left-Behind Children: Gaps in the Existing Knowledge
Authors: Yassir Mohammed
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The study examines the impact of skilled parental migration on left-behind children. It uses the SCOPUS database to evaluate the existing literature from 1972 to 2022 and synthesizes data using the PRISMA framework and bibliometric method of analysis. 49 articles out of 202 papers were involved in the synthesis. International migration, outcome migration, consequence, parental migration, high-skill and left-behind children, and left-behind preschool were all searched. The research found that mental health issues, self-isolation, and physical harm have negative impacts, while sending children to good schools, having good academic records, and better medical care have positive impacts. The study also found that gender gaps increase in some countries while decreasing in others. Further research is needed on child maltreatment, academic performance, subjective well-being, societal effects, behavioral difficulties, and quality of life. The study only included peer-reviewed English publications in the final analysis.Keywords: parental migration, impact of migration, systematic review, left-behind children
Procedia PDF Downloads 61611 Is There Relationship between Cyberchondria and Emotional Intelligence among Omani University Students? A Descriptive Correlational Study
Authors: Mohammed Qutishat, Khaldoun Aldiabat, Khaled Bader, Mohammad Al Qadire
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Cyberchondria refers to the irrational increase of distress about the condition of one's health as a consequence of the World Wide Web quest for medical details. The aim of this study was to examine the relationship between emotional intelligence and cyberchondria among Omani university students. A descriptive correlational design was used to collect data from eligible 370 participants using the Emotional Intelligence Questionnaire, and the short-form version of the Cyberchondria Severity Scale (CSS-12) between January and May 2020 at XX University-Oman. The participants’ age ranged between 18 and 37 years (M = 20.28). The majority of the participants were female, 59.7% (n = 221), single 99.5% (368), in their second academic year, 29.2% (n =108). The mean score of cyberchondria experiences was 32.51, and the mean score of emotional intelligence was 34.91. Linear regression indicated a strong association between cyberchondria and emotional intelligence [F (34.639) = 5.885, P=.000], with a .086 R². In conclusion, the exchange of expertise and peer networking for health-related details utilizing the Internet can benefit students with and without having health problems. Further research and methods should be developed to help students track the online medical tools effectively for the right purposes.Keywords: emotional intelligence, cyberchondria, smartphone addiction, social media
Procedia PDF Downloads 235610 Perception of Aerospace Engineering Students in Saudi Arabia on Aviation Sustainability
Authors: Badr A. Al-Harbi, Fahd T. Abdullah, Mazen T. Wali, Mohammed W. Al-Obaidi, Reda M. Bakhdlg
Abstract:
Over the past few years, the aviation society had demonstrated a huge concern for securing the sustainability of commercial aviation. Future aerospace engineers in Saudi Arabia are expected to play a major role in dealing with these aspects, taking into consideration the expected growth in both traffic, passenger mileage, and fleet expansions in the region. In the present work, the authors investigate the perception of engineering students in the two undergraduate aerospace engineering programs in the Kingdom. A questionnaire was distributed using google forms and targeted approximately 300 students in both programs on several WhatsApp groups. Data collection was stopped after one week when a response rate above 35% was reached. The questionnaire aimed at assessing the students’ awareness of sustainable aviation and associated obstacles. The results obtained from the study indicate the necessity of introducing curricular modifications to address the subject with more targeted extracurricular activities and better use of social media, which is becoming a main source of students’ awareness.Keywords: aviation, engineering education, students’ perception, sustainable aviation
Procedia PDF Downloads 148