Search results for: Sulaiman Ahmed
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1620

Search results for: Sulaiman Ahmed

1590 A New Floating Point Implementation of Base 2 Logarithm

Authors: Ahmed M. Mansour, Ali M. El-Sawy, Ahmed T. Sayed

Abstract:

Logarithms reduce products to sums and powers to products; they play an important role in signal processing, communication and information theory. They are primarily used for hardware calculations, handling multiplications, divisions, powers, and roots effectively. There are three commonly used bases for logarithms; the logarithm with base-10 is called the common logarithm, the natural logarithm with base-e and the binary logarithm with base-2. This paper demonstrates different methods of calculation for log2 showing the complexity of each and finds out the most accurate and efficient besides giving in- sights to their hardware design. We present a new method called Floor Shift for fast calculation of log2, and then we combine this algorithm with Taylor series to improve the accuracy of the output, we illustrate that by using two examples. We finally compare the algorithms and conclude with our remarks.

Keywords: logarithms, log2, floor, iterative, CORDIC, Taylor series

Procedia PDF Downloads 490
1589 Application of Nanofiltration Membrane for River Nile Water Treatment in Egypt

Authors: Tarek S. Jamil, Ahmed M. Shaban, Eman S. Mansor, Ahmed A. Karim, Azza M. Abdel Aty

Abstract:

In this manuscript, 35 m³/d NF unit was designed and applied for surface water treatment of river Nile water. Intake of Embaba drinking water treatment plant was selected to install that unit at since; it has the lowest water quality index value through the examined 6 sites in greater Cairo area. The optimized operating conditions were feed and permeate flow, 40 and 7 m³/d, feed pressure 2.68 bar and flux rate 37.7 l/m2.h. The permeate water was drinkable according to Egyptian Ministerial decree 458/2007 for the tested parameters (physic-chemical, heavy metals, organic, algal, bacteriological and parasitological). Single and double sand filters were used as pretreatment for NF membranes, but continuous clogging for sand filters moved us to use UF membrane as pretreatment for NF membrane.

Keywords: River Nile, NF membrane, pretreatment, UF membrane, water quality

Procedia PDF Downloads 676
1588 Influence of Chirp of High-Speed Laser Diodes and Fiber Dispersion on Performance of Non-Amplified 40-Gbps Optical Fiber Links

Authors: Ahmed Bakry, Moustafa Ahmed

Abstract:

We model and simulate the combined effect of fiber dispersion and frequency chirp of a directly modulated high-speed laser diode on the figures of merit of a non-amplified 40-Gbps optical fiber link. We consider both the return to zero (RZ) and non-return to zero (NRZ) patterns of the pseudorandom modulation bits. The performance of the fiber communication system is assessed by the fiber-length limitation due to the fiber dispersion. We study the influence of replacing standard single-mode fibers by non-zero dispersion-shifted fibers on the maximum fiber length and evaluate the associated power penalty. We introduce new dispersion tolerances for 1-dB power penalty of the RZ and NRZ 40-Gbps optical fiber links.

Keywords: bit error rate, dispersion, frequency chirp, fiber communications, semiconductor laser

Procedia PDF Downloads 613
1587 A Compilation of Nanotechnology in Thin Film Solar Cell Devices

Authors: Nurul Amziah Md Yunus, Izhal Abdul Halin, Nasri Sulaiman, Noor Faezah Ismail, Nik Hasniza Nik Aman

Abstract:

Nanotechnology has become the world attention in various applications including the solar cells devices due to the uniqueness and benefits of achieving low cost and better performances of devices. Recently, thin film solar cells such as cadmium telluride (CdTe), copper-indium-gallium-diSelenide (CIGS), copper-zinc-tin-sulphide (CZTS), and dye-sensitized solar cells (DSSC) enhanced by nanotechnology have attracted much attention. Thus, a compilation of nanotechnology devices giving the progress in the solar cells has been presented. It is much related to nanoparticles or nanocrystallines, carbon nanotubes, and nanowires or nanorods structures.

Keywords: nanotechnology, nanocrystalline, nanowires, carbon nanotubes, nanorods, thin film solar cells

Procedia PDF Downloads 597
1586 The Role of International Organizations in Educational Reform in Iraq

Authors: Thanaa M. Sulaiman

Abstract:

The Iraqi education system has suffered greatly as a result of wars, political instability, and economic problems. After the fall of Saddam’s regime in 2003, the Iraqi education system was proportionally the most impacted sector. The new administration prioritized educational reforms. International organizations, as well as foreign countries, were in the lead to achieve educational reforms. The current study aims to shed light on the reformation process and the roles of different stakeholders, especially international organizations. It also aims to explore the current problems facing the Iraqi education system. Additionally, it aims to explore the different programs and projects that are funded and implemented by international organizations and the impact of these programs and projects.

Keywords: Iraq, Iraqi education system, educational reform, international organizations

Procedia PDF Downloads 103
1585 Bismuth-Inhibitory Effects on Bacteria and Stimulation of Fungal Growth In vitro

Authors: Sulaiman B. Ali Alharbi, Bassam H. Mashat, Naif Abdullah Al-Harbi, Milton Wainwright, Abeer S. Aloufi, Sulamain Alnaimat

Abstract:

Bismuth salicylate was found to inhibit the growth of a range of bacteria and yeast, Candida albican. In general the growth of bacteria did not result in the increase in bismuth solubilisation, in contrast, bismuth solubilisation increased following the growth of C. albicans. A significant increase in the biomass (dry weight) of Aspergillus niger and Aspergillus oryzae occurred in vitro when these fungi were grown in the presence of bismuth salicylate. Biomass increase occurred over a range of bismuth compound additions, which in the case of A. oryzae was associated with the increase in the solubilisation of the insoluble bismuth compounds.

Keywords: bacterial inhibition, fungal growth stimulation, medical uses of bismuth, yeast inhibition

Procedia PDF Downloads 313
1584 Cascade Screening for Beta-Thalassemia in Pakistan: Relatives’ Experiences of a Decision Support Intervention in Routine Practice

Authors: Shenaz Ahmed, Hussain Jafri, Muhammed Faran, Wajeeha Naseer Ahmed, Yasmin Rashid, Yasmin Ehsan, Shabnam Bashir, Mushtaq Ahmed

Abstract:

Low uptake of cascade screening for βeta-Thalassaemia Major (β-TM) in the ‘Punjab Thalassaemia Prevention Project’ (PTPP) in Pakistan led to the development of a ‘decision support intervention for relatives’ (DeSIRe). This paper presents the experiences of relatives of children with β-TM of the DeSIRe following its use by PTPP field officers in routine clinical practice. Fifty-four semi-structured qualitative interviews were conducted (April to June 2021) with relatives in seven cities in the Punjab province (Lahore, Sheikhupura, Nankana Sahab, Kasur, Gujranwala, Multan, and Faisalabad). Thematic analysis shows that participants were satisfied with the content of the DeSIRe and its delivery by the field officers in a family meeting. They understood the main purpose of the DeSIRe was to improve their knowledge of β-TM and its inheritance, to enable them to make decisions about thalassemia carrier testing, particularly before marriage. While participants raised concerns about the stigma of testing positive, they believed the DeSIRe was an appropriate intervention, which supported relatives to make informed decisions. Our findings show the DeSIRe is appropriate for use by healthcare professionals in routine practice in a low-middle income country and has the potential to facilitate shared decision-making about cascade screening for thalassemia. Further research is needed to prove the efficacy of the DeSIRe.

Keywords: thalassemia, Pakistan, cascade screening, decision support

Procedia PDF Downloads 214
1583 Prevalence and Potential Risk Factors Associated with Skin Affection in Donkeys

Authors: Mohamed Z. Sayed-Ahmed, Ahmed M. Ahdy, Emad E. Younis, Sabry A. El-Khodary

Abstract:

Little research information is available on the prevalence of diseases of donkeys in Egypt. Across sectional study was undertaken between March 2009 and February 2010 to verify the prevalence of skin affection of donkeys. A total of 1134 donkeys in northern Egypt were investigated. A questionnaire was constructed to verify the number of infected contact animals as well as the associated factors. Physical examination was carried out, and the distribution of skin lesions was recorded. Skin scraping and biopsy were obtained to perform bacteriological, mycological, and histopathological examinations. Thirty-five (3.09%) out of 1134 noticed donkeys had skin affections including mange (18/35), dermatophytosis (6/35), bacterial dermatitis (6/35) urticaria (2/35) and allergic dermatitis (3/35). The present results indicate that mange and dermatophytosis are the prevalent skin diseases in donkeys. Contact with other animal species of contaminated environment may contribute to the occurrence of the diseases.

Keywords: donkeys, Egypt, prevalence, skin affection

Procedia PDF Downloads 167
1582 Sustainability Assessment of Municipal Wastewater Treatment

Authors: Yousra Zakaria Ahmed, Ahmed El Gendy, Salah El Haggar

Abstract:

In this paper, our methodology to assess sustainability of wastewater treatment technologies in Egypt is presented. The preliminary list of factors to be considered, as well as their ranking listed. The factors include, but are not limited to pollutants removal efficiency and energy consumption under the environmental dimension, construction cost, operation and maintenance costs and required land area cost under the economic dimension and public acceptance, noise and generating job opportunities for local residents. This methodology is intended to be a user-friendly screening tool to support the decision making process when investigating different wastewater treatment technologies in Egypt. Based on the research work results presented in this paper, it can be generally concluded that the categorization of some of the social and environmental aspects of sustainability is subjective and highly dependent on the local conditions and researchers’ background.

Keywords: sustainability, wastewater treatment, sustainability assessment, Egypt

Procedia PDF Downloads 472
1581 Effect of Neem Leaves Extract (Azadirachta Indica) on Blood Glucose Level and Lipid Profile in Normal and Alloxan-Diabetic Rabbits

Authors: Khalil Abdullah Ahmed Khalil, Elsadig Mohamed Ahmed

Abstract:

Extracts of various plants material capable of decreasing blood sugar have been tested in experimental animal models, and their effects confirmed. Neem or Margose (AzadirachtaIndica) is an indigenous plant believed to have antiviral, antifungal, antidiabetic, and many other properties. In this paper deals with a comparative study of effect of aqueous Neem leaves extract alone or in combination with glibenclamide on alloxan diabetic rabbits. Administration of crude aqueous Neem extract (CANE) alone (1.5 ml/kg/day) as well as the combination of CANE (1.5 ml/kg/day) with glibenclamide (0.25 mg/kg/day) significantly decreased (P<0.05) the concentrations of serum lipids, blood glucose and lipoprotein VLDL and LDL but significantly increased (P<0.05) the concentration of HDL. The change was observed significantly greater when the treatment was given in combination of CANE and glibenclamid than with CANE alone.

Keywords: aqueos neem leaves extract, hypoglycemic, hypolipidemic, cholesterol

Procedia PDF Downloads 136
1580 Street Begging: A Loss of Human Resource in Nigeria

Authors: Sulaiman Kassim Ibrahim

Abstract:

Human Resource is one of the most important elements in any country. They are very important in actualizing the potential of every sector in the country, i.e Agric, Education, Finance, Judiciary and all formal and informal sectors. The purpose of this study is to investigate the loss of human resource in Nigeria through street begging. The study used intensive literature review. Finding from the review indicate that a significant number of human resource are into street begging in the country undeveloped and untapped. The paper recommend that policy should be initiated to discourage street begging, develop this resource through education and empowerment, stop rural-urban migration by providing infrastructure in the rural areas and abolish informal (Almajiri or beggars school) and transform it into formal school.

Keywords: human resource, street begging, Nigeria, Almajiri

Procedia PDF Downloads 219
1579 Graphene-Oxide-Supported Coal-Layered Double Hydroxides: Synthesis and Characterizations

Authors: Shaeel A. Al Thabaiti, Sulaiman N. Basahel, Salem M. Bawaked, Mohamed Mokhtar

Abstract:

Nanosheets for cobalt-layered double hydroxide (Co-Al-LDH)/GO were successfully synthesized with different Co:M g:Al ratios (0:3:1, 1.5:1.5:1, and 3:0:1). The layered double hydroxide structure and morphology were determined using x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Temperature prgrammed reduction (TPR) of Co-Al-LDH showed reduction peaks at lower temperature which indicates the ease reducibility of this particular sample. The thermal behaviour was studied using thermal graviemetric technique (TG), and the BET-surface area was determined using N2 physisorption at -196°C. The C-C coupling reaction was carried out over all the investigated catalysts. The Mg–Al LDH catalyst without Co ions is inactive, but the isomorphic substitution of Mg by Co ions (Co:Mg:Al = 1.5:1.5:1) in the cationic sheet resulted in 88% conversion of iodobenzene under reflux. LDH/GO hybrid is up to 2 times higher activity than for the unsupported LDH.

Keywords: adsorption, co-precipitation, graphene oxide, layer double hydroxide

Procedia PDF Downloads 271
1578 Transient Analysis of Laminated Rubber Bearing Bridge during High Intensity Earthquake

Authors: N. M. Amin, W. N. A. W. Sulaiman

Abstract:

The effectiveness of the seismic response between 3D solid elements model and simplified beam elements model has been investigated. At present, the studies of the numerical modelling using 3D solid element are minimal due to numerical software constraint. The finite element analysis using 3D solid element was chosen to study displacement response of laminated rubber bearing (LRB) during high intensity Kobe earthquake. In this research a simply supported bridge (single span), fixed at support was analysed by using transient analysis subjected to real time history loading of Kobe earthquake.

Keywords: laminated rubber bearing, solid element, simplified beam element, transient analysis

Procedia PDF Downloads 401
1577 The Literary Works of Sir Sayeed Ahmed Khan and Its Impact on Indian Muslims

Authors: Mohammad Arifur Rahman

Abstract:

The research study aims to bring to light the contribution of sir Sayeed Ahmed in the realm of education and literature. Sir Sayeed Ahmed Khan (1817 –1898), commonly known as Sir Sayeed, was an Indian Muslim leader, Islamic modernist, philosopher and social reformer of the nineteenth century. He earned a reputation as a distinguished scholar while working as a jurist for British India. During the Indian Rebellion of 1857, he remained loyal to the British Empire and was noted for his actions in saving European lives. Believing that the future of Muslims was threatened by the rigidity of their orthodox outlook, Sir Sayeed began promoting Western–style scientific education by founding modern schools and journals and organizing Muslim entrepreneurs. He was one of the founders of the Aligarh Movement and Aligarh Muslim University. He began focusing on writing, from his early life, on various subjects, mainly educational issues. He launched his attempts to revive the spirit of progress within the Muslim community of India. Therefore, modern education became the pivot of his movement for the regeneration of the Indian Muslims. Sayeed Ahmed Khan found time for literary and scholarly pursuits. The range of his literary and scholarly interests was very wide, comprising all the major areas: education, law, philosophy, history, politics, archeology, journalism, Muslim modernism, literature, science and culture, mainly based on his comprehensive religious ideas should be well measured in view to making out him and his contribution to the context. The books written by himself and the books composed by him by some of the great writers like Altaf Hussein Hali, Hafee z Malick, Nasim Rashid, and Christian W. Troll were studied to understand him and his contribution. The readers of this paper would benefit from dispelling the hazy ideas about this great man of India who made an immense contribution. Further research should be undertaken to know more about the different sides of his thought and personality. The qualitative and the historical methods are adopted for the accomplishment of the work.

Keywords: thinker, reformer, educator and Philosopher, modernist

Procedia PDF Downloads 72
1576 Contact Temperature of Sliding Surfaces in AISI 316 Austenitic Stainless Steel During PIN on Disk Dry Wear Testing

Authors: Dler Abdullah Ahmed, Zozan Ahmed Mohammed

Abstract:

This study looked into contact surface temperature during a pin-on-disk test. Friction and wear between sliding surfaces raised the temperature differential between the contact surface and ambient temperatures Tdiff. Tdiff was significantly influenced by wear test variables. Tdiff rose with the increase of sliding speed and applied load while dropped with the increase in ambient temperature. The highest Tdiff was 289°C during the tests at room temperature and 2.5 m/s sliding speed, while the minimum was only 24 °C during the tests at 400°C and 0.5 m/s. However, the maximum contact temperature Tmax was found during tests conducted at high ambient temperatures. The Tmax was estimated based on the theoretical equation. The comparison of experimental and theoretical Tmax data revealed good agreement.

Keywords: pin on disk test, contact temperature, wear, sliding surface, friction, ambient temperature

Procedia PDF Downloads 37
1575 Effect of Ginger (Zingiber Officinal) Root Extract on Blood Glucose Level and Lipid Profile in Normal and Alloxan-Diabetic Rabbits

Authors: Khalil Abdullah Ahmed Khalil, Elsadig Mohamed Ahmed

Abstract:

Ginger is one of the most important medicinal plants, which is widely used in folk medicine. This study was designed to go further step and evaluate the hypoglycemic and hypolipidaemic effects of the aqueous ginger root extract in normal and alloxan diabetic rabbits. Results revealed that the aqueous ginger has a significant hypoglycemic effect (P<0.05) in diabetic rabbits but a non-significant hypoglycemic effect (P>0.05) in normal rabbits. There were also significant decreases in the concentrations (P<0.05) in serum cholesterol, triglycerides and LDL – cholesterol in both normal and diabetic rabbits. Although there was an elevation in serum HDL- cholesterol in both normal and diabetic rabbits, these elevations were non-significant (P>0.05). Our data suggest the aqueous ginger has a hypoglycemic effect in diabetic rabbits and lipid-lowering properties in both normal and diabetic rabbits.

Keywords: aqueous extract of ginger root (AEGR), hypoglycemic, cholesterol, triglyceride

Procedia PDF Downloads 254
1574 Application of Strong Optical Feedback to Enhance the Modulation Bandwidth of Semiconductor Lasers to the Millimeter-Wave Band

Authors: Moustafa Ahmed, Ahmed Bakry, Fumio Koyama

Abstract:

We report on the use of strong external optical feedback to enhance the modulation response of semiconductor lasers over a frequency passband around modulation frequencies higher than 60 GHz. We show that this modulation enhancement is a type of photon-photon resonance (PPR) of oscillating modes in the external cavity formed between the laser and the external reflector. The study is based on a time-delay rate equation model that takes into account both the strong feedback and multiple reflections in the external cavity. We examine the harmonic and intermodulation distortions associated with single and two-tone modulations in the mm-wave band of the resonant modulation. We show that compared with solitary lasers modulated around the carrier-photon resonance frequency, the present mm-wave modulated signal has lower distortions.

Keywords: semiconductor laser, optical feedback, modulation, harmonic distortion

Procedia PDF Downloads 713
1573 Antidiabetic and Antihyperlipaemic Effects of Aqueous Neem (Azadirachta Indica) Extract on Alloxan Diabetic Rabbits

Authors: Khalil Abdullah Ahmed Khalil, Elsadig Mohamed Ahmed

Abstract:

Extracts of various plants material capable of decreasing blood sugar have been tested in experimental animal models and their effects confirmed. Neem or Margose (Azadirachta Indica) is an indigenous plant believed to have antiviral, antifungal, antidiabetic and many other properties. This paper deals with a comparative study of the effect of aqueous Neem leaves extract alone or in combination with glibenclamide on alloxan diabetic rabbits. Administration of crude aqueous Neem extract (CANE) alone (1.5 ml/kg/day), as well as the combination of CANE (1.5 ml/kg/day) with glibenclamide (0.25 mg/kg/day) significantly, decreased (P<0.05) the concentrations of serum lipids, blood glucose and lipoprotein VLDL(very low-density lipoproteins) and LDL(low-density lipoproteins) but significantly increased (P<0.05) the concentration of HDL(high-density lipoprotein). The change was observed significantly greater when the treatment was given in combination of CANE and glibenclamid than with CANE alone.

Keywords: neem, hypoglycemic, hypolipidemic, cholesterol

Procedia PDF Downloads 225
1572 Reliability of Slender Reinforced Concrete Columns: Part 1

Authors: Metwally Abdel Aziz Ahmed, Ahmed Shaban Abdel Hay Gabr, Inas Mohamed Saleh

Abstract:

The main objective of structural design is to ensure safety and functional performance requirements of a structural system for its target reliability levels. In this study, the reliability index for the reinforcement concrete slender columns with rectangular cross section is studied. The variable parameters studied include the loads, the concrete compressive strength, the steel yield strength, the dimensions of concrete cross-section, the reinforcement ratio, and the location of steel placement. Risk analysis program was used to perform the analytical study. The effect of load eccentricity on the reliability index of reinforced concrete slender column was studied and presented. The results of this study indicate that the good quality control improve the performance of slender reinforced columns through increasing the reliability index β.

Keywords: reliability, reinforced concrete, safety, slender column

Procedia PDF Downloads 425
1571 Multi-Criteria Decision Making Approaches for Facility Planning Problem Evaluation: A Survey

Authors: Ahmed M. El-Araby, Ibrahim Sabry, Ahmed El-Assal

Abstract:

The relationships between the industrial facilities, the capacity available for these facilities, and the costs involved are the main factors in deciding the correct selection of a facility layout. In general, an issue of facility layout is considered to be an unstructured problem of decision-making. The objective of this work is to provide a survey that describes the techniques by which a facility planning problem can be solved and also the effect of these techniques on the efficiency of the layout. The multi-criteria decision making (MCDM) techniques can be classified according to the previous researches into three categories which are the use of single MCDM, combining two or more MCDM, and the integration of MCDM with another technique such as genetic algorithms (GA). This paper presents a review of different multi-criteria decision making (MCDM) techniques that have been proposed in the literature to pick the most suitable layout design. These methods are particularly suitable to deal with complex situations, including various criteria and conflicting goals which need to be optimized simultaneously.

Keywords: facility layout, MCDM, GA, literature review

Procedia PDF Downloads 172
1570 IoT: State-of-the-Art and Future Directions

Authors: Bashir Abdu Muzakkari, Aisha Umar Sulaiman, Mohamed Afendee Muhamad, Sanah Abdullahi Muaz

Abstract:

The field of the Internet of Things (IoT) is rapidly expanding and has the potential to completely change how we work, live, and interact with the world. The Internet of Things (IoT) is the term used to describe a network of networked physical objects, including machinery, vehicles, and buildings, which are equipped with electronics, software, sensors, and network connectivity. This review paper aims to provide a comprehensive overview of the current state of IoT, including its definition, key components, development history, and current applications. The paper will also discuss the challenges and opportunities presented by IoT, as well as its potential impact on various industries, such as healthcare, agriculture, and transportation. In addition, this paper will highlight the ethical and security concerns associated with IoT and the need for effective solutions to address these challenges. The paper concludes by highlighting the prospects of IoT and the directions for future research in this field.

Keywords: internet of things, IoT, sensors, network

Procedia PDF Downloads 146
1569 A Fully-Automated Disturbance Analysis Vision for the Smart Grid Based on Smart Switch Data

Authors: Bernardo Cedano, Ahmed H. Eltom, Bob Hay, Jim Glass, Raga Ahmed

Abstract:

The deployment of smart grid devices such as smart meters and smart switches (SS) supported by a reliable and fast communications system makes automated distribution possible, and thus, provides great benefits to electric power consumers and providers alike. However, more research is needed before the full utility of smart switch data is realized. This paper presents new automated switching techniques using SS within the electric power grid. A concise background of the SS is provided, and operational examples are shown. Organization and presentation of data obtained from SS are shown in the context of the future goal of total automation of the distribution network. The description of application techniques, the examples of success with SS, and the vision outlined in this paper serve to motivate future research pertinent to disturbance analysis automation.

Keywords: disturbance automation, electric power grid, smart grid, smart switches

Procedia PDF Downloads 285
1568 Variants of Mathematical Induction as Strong Proof Techniques in Theory of Computing

Authors: Ahmed Tarek, Ahmed Alveed

Abstract:

In the theory of computing, there are a wide variety of direct and indirect proof techniques. However, mathematical induction (MI) stands out to be one of the most powerful proof techniques for proving hypotheses, theorems, and new results. There are variations of mathematical induction-based proof techniques, which are broadly classified into three categories, such as structural induction (SI), weak induction (WI), and strong induction (SI). In this expository paper, several different variants of the mathematical induction techniques are explored, and the specific scenarios are discussed where a specific induction technique stands out to be more advantageous as compared to other induction strategies. Also, the essential difference among the variants of mathematical induction are explored. The points of separation among mathematical induction, recursion, and logical deduction are precisely analyzed, and the relationship among variations of recurrence relations, and mathematical induction are being explored. In this context, the application of recurrence relations, and mathematical inductions are considered together in a single framework for codewords over a given alphabet.

Keywords: alphabet, codeword, deduction, mathematical, induction, recurrence relation, strong induction, structural induction, weak induction

Procedia PDF Downloads 142
1567 Investigation of Specific Wear Rate of Austenitic and Duplex Stainless Steel Alloys in High Temperatures

Authors: Dler Abdullah Ahmed, Zozan Ahmed Mohammed

Abstract:

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 41
1566 Investigation of Specific Wear Rate of Austenitic and Duplex Stainless Steel Alloys in High Temperatures

Authors: Dler Abdullah Ahmed, Zozan Ahmed Mohammed

Abstract:

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 36
1565 Evaluation of Dynamic Log Files for Different Dose Rates in IMRT Plans

Authors: Saad Bin Saeed, Fayzan Ahmed, Shahbaz Ahmed, Amjad Hussain

Abstract:

The aim of this study is to evaluate dynamic log files (Dynalogs) at different dose rates by dose-volume histograms (DVH) and used as a (QA) procedure of IMRT. Seven patients of phase one head and neck cancer with similar OAR`s are selected randomly. Reference plans of dose rate 300 and 600 MU/Min with prescribed dose of 50Gy in 25 fractions for each patient is made. Dynalogs produced by delivery of reference plans processed by in-house MATLAB program which produces new field files contain actual positions of multi-leaf collimators (MLC`s) instead of planned positions in reference plans. Copies of reference plans are used to import new field files generated by MATLAB program and renamed as Dyn.plan. After dose calculations of Dyn.plans for different dose rates, DVH, and multiple linear regression tools are used to evaluate reference and Dyn.plans. The results indicate good agreement of correlation between different dose rate plans. The maximum dose difference among PTV and OAR`s are found to be less than 5% and 9% respectively. The study indicates the potential of dynalogs to be used as patient-specific QA of IMRT at different dose rate.

Keywords: IMRT, dynalogs, dose rate, DVH

Procedia PDF Downloads 511
1564 Design of Residential Geothermal Cooling System in Kuwait

Authors: Tebah KH A AlFouzan, Meznah Dahlous Ali Alkreebani, Fatemah Salem Dekheel Alrasheedi, Hanadi Bandar Rughayan AlNomas, Muneerah Mohammad Sulaiman ALOjairi

Abstract:

Article spotlights the heat transfer process based beneath the earth’s surface. The process starts by exchanging the heat found in the building as fluid in the pipes absorbs it, then transports it down the soil consuming cool temperature exchange, recirculating, and rebounding to deliver cool air. This system is a renewable energy that is reliable and sustainable. The analysis showed the disposal of fossil fuels, energy preservation, 400% efficiency, long lifespan, and lower maintenance. Investigation displays the system’s types of design, whether open or closed loop and piping layout. Finally, the geothermal cooling study presents the challenges of creating a prototype in Kuwait, as constraints are applicable due to geography.

Keywords: cooling system, engineering, geothermal cooling, natural ventilation, renewable energy

Procedia PDF Downloads 56
1563 Effect of Pulse Duration and Current to the EDM Process on Allegheny Ludlum D2 Tool Steel

Authors: S. Sulaiman, M. A. Razak, M. R. Ibrahim, A. A. Khan

Abstract:

An experimental work on the effect of different current and pulse duration on performance of EDM process of Allegheny Ludlum D2 Tool Steel (UNS T30402). The effect of varying the machining parameters on the machining responses such as material removal rate (MRR), electrode wear rate (EWR), and surface roughness (Ra) have been investigated. In this study, triangular shape and circular shape of copper was used as an electrode with surface area of 100 mm². The experiments were repeated for three different values of pulse duration (100 µs, 200 µs and 400 µs) with combination of three different values of discharge current (12 A, 16 A and 24 A). It was found that the pulse duration and current have significant effect on MRR, EWR and Ra. An increase in the pulse durations causes an increase in the MRR and Ra, but a decrease in the EWR. Meanwhile, the effect of currents on EDM performance shows that the increasing currents lead to an increase in the MRR, EWR and Ra.

Keywords: allegheny ludlum D2 tool steel, current, EDM, surface roughness, pulse duration

Procedia PDF Downloads 358
1562 RNA-Seq Analysis of the Wild Barley (H. spontaneum) Leaf Transcriptome under Salt Stress

Authors: Ahmed Bahieldin, Ahmed Atef, Jamal S. M. Sabir, Nour O. Gadalla, Sherif Edris, Ahmed M. Alzohairy, Nezar A. Radhwan, Mohammed N. Baeshen, Ahmed M. Ramadan, Hala F. Eissa, Sabah M. Hassan, Nabih A. Baeshen, Osama Abuzinadah, Magdy A. Al-Kordy, Fotouh M. El-Domyati, Robert K. Jansen

Abstract:

Wild salt-tolerant barley (Hordeum spontaneum) is the ancestor of cultivated barley (Hordeum vulgare or H. vulgare). Although the cultivated barley genome is well studied, little is known about genome structure and function of its wild ancestor. In the present study, RNA-Seq analysis was performed on young leaves of wild barley treated with salt (500 mM NaCl) at four different time intervals. Transcriptome sequencing yielded 103 to 115 million reads for all replicates of each treatment, corresponding to over 10 billion nucleotides per sample. Of the total reads, between 74.8 and 80.3% could be mapped and 77.4 to 81.7% of the transcripts were found in the H. vulgare unigene database (unigene-mapped). The unmapped wild barley reads for all treatments and replicates were assembled de novo and the resulting contigs were used as a new reference genome. This resultedin94.3 to 95.3%oftheunmapped reads mapping to the new reference. The number of differentially expressed transcripts was 9277, 3861 of which were uni gene-mapped. The annotated unigene- and de novo-mapped transcripts (5100) were utilized to generate expression clusters across time of salt stress treatment. Two-dimensional hierarchical clustering classified differential expression profiles into nine expression clusters, four of which were selected for further analysis. Differentially expressed transcripts were assigned to the main functional categories. The most important groups were ‘response to external stimulus’ and ‘electron-carrier activity’. Highly expressed transcripts are involved in several biological processes, including electron transport and exchanger mechanisms, flavonoid biosynthesis, reactive oxygen species (ROS) scavenging, ethylene production, signaling network and protein refolding. The comparisons demonstrated that mRNA-Seq is an efficient method for the analysis of differentially expressed genes and biological processes under salt stress.

Keywords: electron transport, flavonoid biosynthesis, reactive oxygen species, rnaseq

Procedia PDF Downloads 364
1561 The Current Status of Integrating Information and Communication Technology in Teaching at Sultan Qaboos University

Authors: Ahmed Abdelrahman, Ahmed Abdelraheem

Abstract:

There are many essential factors affecting the integration of information and communication technology (ICT) into teaching and learning, including technology infrastructure, institutional support, professional development, and faculty members’ beliefs regarding ICT integration. The present research project investigated the current status of integrating ICT into teaching and learning at Sultan Qaboos University (SQU). A sample of 220 faculty members from six different colleges and four administrators from the Center of Educational Technology (CET) and the Center for Information Systems (CIS) at SQU in Oman were chosen, and quantitative, qualitative design using a semi-structured questionnaire, interviews and checklists were employed. The findings show that SQU had a high availability of ICT infrastructure in terms of hardware, software, and support services, as well as adequate computer labs for educational purposes. However, the results also indicated that, although SQU provided a series of professional development workshops related to using ICT in teaching, few faculty members were interested. Furthermore, the finding indicated that the degree of ICT integration into teaching at SQU was at a medium level.

Keywords: information and communication technology, integration, professional development, teaching

Procedia PDF Downloads 139