Search results for: Mohamed Ahmed Tony
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2934

Search results for: Mohamed Ahmed Tony

1284 Numerical Study for Improving Performance of Air Cooled Proton Exchange Membrane Fuel Cell on the Cathode Channel

Authors: Mohamed Hassan Gundu, Jaeseung Lee, Muhammad Faizan Chinannai, Hyunchul Ju

Abstract:

In this study, we present the effects of bipolar plate design to control the temperature of the cell and ensure effective water management under an excessive amount of air flow and low humidification conditions in the proton exchange membrane fuel cell (PEMFC). The PEMFC model developed and applied to consider a three type of bipolar plate that is defined by ratio of inlet channel width to outlet channel width. Simulation results show that the design which has narrow gas inlet channel and wide gas outlet channel width (wide coolant inlet channel and narrow coolant outlet channel width) make the relative humidity and water concentration increase in the channel and the catalyst layer. Therefore, this study clearly demonstrates that the dehydration phenomenon can be decreased by using design of bipolar plate with narrow gas inlet channel and wide gas outlet channel width (wide coolant inlet channel and narrow coolant outlet channel width).

Keywords: PEMFC, air-cooling, relative humidity, water management, water concentration, oxygen concentration

Procedia PDF Downloads 278
1283 A Comparative Study on Indian and Greek Cotton Fiber Properties Correlations

Authors: Md. Nakib Ul Hasan, Md. Ariful Islam, Md. Sumon Miah, Misbah Ul Hoque, Bulbul Ahmed

Abstract:

The variability of cotton fiber characteristics has always been influenced by origin, weather conditions, method of culturing, and harvesting. Spinners work tirelessly to ensure consistent yarn quality by using the different origins of fibers to maximizes the profit margin. Spinners often fail to select desired raw materials of various origins to achieve an appropriate mixing plan due to the lack of knowledge on the interrelationship among fiber properties. The purpose of this research is to investigate the correlations among dominating fiber properties such as micronaire, strength, breaking elongation, upper half mean length, length uniformity index, short fiber index, maturity, reflectance, and yellowness. For this purpose, fiber samples from 500 Indian cotton bales and 350 Greek cotton bales were collected and tested using the high volume instrument (HVI). The fiber properties dataset was then compiled and analyzed using python 3.7 to determine the correlations matrix. Results show that Indian cotton fiber have highest correlation between strength-mat = 0.84, followed by SFI-Unf =-0.83, and Neps-Unf = -0.72. Greek cotton fiber, in contrast, have highest correlation between SFI-Unf =-0.98, followed by SFI-Mat = 0.89, +b-Len = 0.84, and Str-Mat = 0.74. Overall, the Greek cotton fiber showed a higher correlational matrix than compared to that of Indian cotton fiber.

Keywords: cotton fiber, fiber properties correlation, Greek cotton, HVI, Indian cotton, spinning

Procedia PDF Downloads 143
1282 Geophysical Contribution to Reveal the Subsurface Structural Setting Using Gravity, Seismic and Seismological Data in the Chott Belts, Southern Atlas of Tunisia

Authors: Nesrine Frifita, Mohamed Gharbi, Kevin Mickus

Abstract:

Physical methods based on gravity, seismic and seismological data were adopted to clarify the relationship between the distribution of seismicity and the crustal deformations under the chott belts and surrounding regions, in southern atlas of Tunisia. Gafsa and its surrounding were described as a moderate seismic zone, and the fault of Gafsa is one of most seismically active faults in Tunisia in general, and in the southern Atlas in particularly. The present work aims to prove a logical relationship between the distribution of seismicity and deformations which strongly related to thickness and density variations within the basement and sedimentary cover along the study area, through several physical methods; gravity, seismic and seismological data were interpreted to calculate physical propriety of the subsurface rocks, the depth and geometry of active faults and causatives bodies. Findings show that depths variation and mixed thin and thick skinned structural style characterizing the chott belts explain the moderate seismicity in the study area.

Keywords: potential fields, seismicity, Southern Atlas, Tunisia

Procedia PDF Downloads 97
1281 Application of Universal Distribution Factors for Real-Time Complex Power Flow Calculation

Authors: Abdullah M. Alodhaiani, Yasir A. Alturki, Mohamed A. Elkady

Abstract:

Complex power flow distribution factors, which relate line complex power flows to the bus injected complex powers, have been widely used in various power system planning and analysis studies. In particular, AC distribution factors have been used extensively in the recent power and energy pricing studies in free electricity market field. As was demonstrated in the existing literature, many of the electricity market related costing studies rely on the use of the distribution factors. These known distribution factors, whether the injection shift factors (ISF’s) or power transfer distribution factors (PTDF’s), are linear approximations of the first order sensitivities of the active power flows with respect to various variables. This paper presents a novel model for evaluating the universal distribution factors (UDF’s), which are appropriate for an extensive range of power systems analysis and free electricity market studies. These distribution factors are used for the calculations of lines complex power flows and its independent of bus power injections, they are compact matrix-form expressions with total flexibility in determining the position on the line at which line flows are measured. The proposed approach was tested on IEEE 9-Bus system. Numerical results demonstrate that the proposed approach is very accurate compared with exact method.

Keywords: distribution factors, power system, sensitivity factors, electricity market

Procedia PDF Downloads 457
1280 On Unification of the Electromagnetic, Strong and Weak Interactions

Authors: Hassan Youssef Mohamed

Abstract:

In this paper, we show new wave equations, and by using the equations, we concluded that the strong force and the weak force are not fundamental, but they are quantum effects for electromagnetism. This result is different from the current scientific understanding about strong and weak interactions at all. So, we introduce three evidences for our theory. First, we prove the asymptotic freedom phenomenon in the strong force by using our model. Second, we derive the nuclear shell model as an approximation of our model. Third, we prove that the leptons do not participate in the strong interactions, and we prove the short ranges of weak and strong interactions. So, our model is consistent with the current understanding of physics. Finally, we introduce the electron-positron model as the basic ingredients for protons, neutrons, and all matters, so we can study all particles interactions and nuclear interaction as many-body problems of electrons and positrons. Also, we prove the violation of parity conservation in weak interaction as evidence of our theory in the weak interaction. Also, we calculate the average of the binding energy per nucleon.

Keywords: new wave equations, the strong force, the grand unification theory, hydrogen atom, weak force, the nuclear shell model, the asymptotic freedom, electron-positron model, the violation of parity conservation, the binding energy

Procedia PDF Downloads 161
1279 Understanding of Heritage Values within University Education Systems in the Kingdom of Saudi Arabia

Authors: Mahmoud Tarek Mohamed Hammad

Abstract:

Despite the importance of the role and efforts made by the universities of the Kingdom of Saudi Arabia in reviving and preserving heritage architecture as an important cultural heritage in the Kingdom, The idea revolves around restoration and conservation processes and neglects the architectural heritage values, whose content can be used in sustainable contemporary architectural works. Educational values based on heritage architecture and how to integrate with the contemporary requirements were investigated in this research. For this purpose, by understanding the heritage architectural values as well as educational, academic process, the researcher presented an educational model of questionnaire forms for architecture students and the staff at the Architecture Department at Al-Baha University as a case study that serves the aims of the research. The results of the research show that heritage values especially those interview results are considered as a positive indicator of the importance of these values. The students and the staff need both to gain an understanding of heritage values as well as an understanding of theories of incorporating those values into the design process of contemporary local architecture. The research concludes that a correct understanding of the heritage values, its performance, and its reintegration with modern architecture technology should be focused on architectural education.

Keywords: heritage architecture, academic work, heritage values, sustainable contemporary local architectural

Procedia PDF Downloads 145
1278 Left to Right-Right Most Parsing Algorithm with Lookahead

Authors: Jamil Ahmed

Abstract:

Left to Right-Right Most (LR) parsing algorithm is a widely used algorithm of syntax analysis. It is contingent on a parsing table, whereas the parsing tables are extracted from the grammar. The parsing table specifies the actions to be taken during parsing. It requires that the parsing table should have no action conflicts for the same input symbol. This requirement imposes a condition on the class of grammars over which the LR algorithms work. However, there are grammars for which the parsing tables hold action conflicts. In such cases, the algorithm needs a capability of scanning (looking-ahead) next input symbols ahead of the current input symbol. In this paper, a ‘Left to Right’-‘Right Most’ parsing algorithm with lookahead capability is introduced. The 'look-ahead' capability in the LR parsing algorithm is the major contribution of this paper. The practicality of the proposed algorithm is substantiated by the parser implementation of the Context Free Grammar (CFG) of an already proposed programming language 'State Controlled Object Oriented Programming' (SCOOP). SCOOP’s Context Free Grammar has 125 productions and 192 item sets. This algorithm parses SCOOP while the grammar requires to ‘look ahead’ the input symbols due to action conflicts in its parsing table. Proposed LR parsing algorithm with lookahead capability can be viewed as an optimization of ‘Simple Left to Right’-‘Right Most’ (SLR) parsing algorithm.

Keywords: left to right-right most parsing, syntax analysis, bottom-up parsing algorithm

Procedia PDF Downloads 103
1277 Gas Lift Optimization Using Smart Gas Lift Valve

Authors: Mohamed A. G. H. Abdalsadig, Amir Nourian, G. G. Nasr, M. Babaie

Abstract:

Gas lift is one of the most common forms of artificial lift, particularly for offshore wells because of its relative down hole simplicity, flexibility, reliability, and ability to operate over a large range of rates and occupy very little space at the well head. Presently, petroleum industry is investing in exploration and development fields in offshore locations where oil and gas wells are being drilled thousands of feet below the ocean in high pressure and temperature conditions. Therefore, gas-lifted oil wells are capable of failure through gas lift valves which are considered as the heart of the gas lift system for controlling the amount of the gas inside the tubing string. The gas injection rate through gas lift valve must be controlled to be sufficient to obtain and maintain critical flow, also, gas lift valves must be designed not only to allow gas passage through it and prevent oil passage, but also for gas injection into wells to be started and stopped when needed. In this paper, smart gas lift valve has been used to investigate the effect of the valve port size, depth of injection and vertical lift performance on well productivity; all these aspects have been investigated using PROSPER simulator program coupled with experimental data. The results show that by using smart gas lift valve, the gas injection rate can be controlled which leads to improved flow performance.

Keywords: Effect of gas lift valve port size, effect water cut, vertical flow performance

Procedia PDF Downloads 277
1276 Role of Social Capital on Consumer Attitudes, Peer Influence and Behavioral Intentions: A Social Media Perspective

Authors: Qazi Mohammed Ahmed, Osman Sadiq Paracha, Iftikhar Hussain

Abstract:

The study aims to explore the unaddressed relationship between social capital and consumers’ underlying behavioral intentions. The study postulates that this association is mediated by the role of attitudes and peer influence. The research attains evidence from a usable sample of 673 responses. The majority consists of the young and energetic social media users of Pakistan that utilize virtual communities as a way of life. A variance based structural equation modeling has been applied through SmartPLS 3. The results reveal that social capital exerts a statistically supportive association with both attitudes and peer influence. Contrastingly, this predictor variable shows an insignificant linkage with behavioral intentions but this relationship is fully mediated by consumer attitudes and peer influence. The paper enhances marketing literature with respect to an unexplored society of Pakistan. It also provides a lens for the contemporary advertisers, in terms of supporting their social media campaigns with affiliative and cohesive elements. The study also identifies a series of predictor variables that could further be tested with attitudes, subjective norms and behavioral responses.

Keywords: social capital, consumer attitudes, peer influence, behavioral intentions

Procedia PDF Downloads 112
1275 Value Added by Spirulina Platensis in Two Different Diets on Growth Performance, Gut Microbiota, and Meat Quality of Japanese Quails

Authors: Mohamed Yusuf

Abstract:

Aim: The growth promoting the effect of the blue-green filamentous alga Spirulina platensis (SP) was observed on meat type Japanese quail with antibiotic growth promoter alternative and immune enhancing power. Materials and Methods: This study was conducted on 180 Japanese quail chicks for 4 weeks to find out the effect of diet type (vegetarian protein diet [VPD] and fish meal protein diet [FMPD])- Spirulina dose interaction (1 or 2 g/kg diet) on growth performance, gut microbiota, and sensory meat quality of growing Japanese quails (1-5 weeks old). Results: Data revealed improvement (p<0.05) of weight gain, feed conversion ratio, and European efficiency index due to 1, 2 g (SP)/kg VPD, and 2 g (SP)/kg FMPD, respectively. There was a significant decrease of ileum mean pH value by 1 g(SP)/kg VPD. Concerning gut microbiota, there was a trend toward an increase in Lactobacilli count in both 1; 2 g (SP)/kgVPD and 2 g (SP)/kg FMPD. It was concluded that 1 or 2 g (SP)/kg vegetarian diet may enhance parameters of performance without obvious effect on both meat quality and gut microbiota. Moreover, 1 and/or 2 g (SP) may not be invited to share fishmeal based diet for growing Japanese quails. Conclusion: Using of SP will support the profitable production of Japanese quails fed vegetable protein diet.

Keywords: isocaloric, isonitrogenous, meat quality, performances, quails, spirulina, spirulina

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1274 Fear and Anxiety among School Age Children Undergoing Dental Treatment in an Oral Health Unit

Authors: Maha Ibrahim Mohamed Khalifa

Abstract:

Background: Dental fear and anxiety lead to avoidance of dental treatment and deterioration of oral health. Aim of the study: To assess the levels of fear and anxiety among school-age children undergoing dental treatment. Setting: The study was conducted in Outpatient Dental Clinics at Benha Teaching Hospital. Research design: A descriptive research design was utilized to conduct the study. Sample: A purposive sample of 60 school-age children and their mothers attending at the previously mentioned setting was included. Tools: Three tools were used: Tool one: A structured interviewing questionnaire for Personal characteristics of children and their mothers. Tool two: Dental Subscale of Children's Fear Survey Schedule (CFSS-DS). Tool three: Modified Dental Anxiety Scale (MDAS). Results: It was illustrated that more than two-fifths (43.3%) of children had maximum fear and more than half of children (53.3%) had maximal anxiety. Conclusion: Many school-age children undergoing dental treatment suffer from high levels of fear and anxiety. Recommendations: The study recommended further research should be conducted to assess levels of fear and anxiety among children undergoing dental treatments and preferable nursing interventions for reducing their fears and anxieties.

Keywords: fear, anxiety, children, dental treatment

Procedia PDF Downloads 69
1273 Spectrum Allocation Using Cognitive Radio in Wireless Mesh Networks

Authors: Ayoub Alsarhan, Ahmed Otoom, Yousef Kilani, Abdel-Rahman al-GHuwairi

Abstract:

Wireless mesh networks (WMNs) have emerged recently to improve internet access and other networking services. WMNs provide network access to the clients and other networking functions such as routing, and packet forwarding. Spectrum scarcity is the main challenge that limits the performance of WMNs. Cognitive radio is proposed to solve spectrum scarcity problem. In this paper, we consider a cognitive wireless mesh network where unlicensed users (secondary users, SUs) can access free spectrum that is allocated to spectrum owners (primary users, PUs). Although considerable research has been conducted on spectrum allocation, spectrum assignment is still considered an important challenging problem. This problem can be solved using cognitive radio technology that allows SUs to intelligently locate free bands and access them without interfering with PUs. Our scheme considers several heuristics for spectrum allocation. These heuristics include: channel error rate, PUs activities, channel capacity and channel switching time. Performance evaluation of the proposed scheme shows that the scheme is able to allocate the unused spectrum for SUs efficiently.

Keywords: cognitive radio, dynamic spectrum access, spectrum management, spectrum sharing, wireless mesh networks

Procedia PDF Downloads 510
1272 Predictive Value of Coagulopathy in Patients with Isolated Blunt Traumatic Brain Injury: A Cohort of Pakistani Population

Authors: Muhammad Waqas, Shahan Waheed, Mohsin Qadeer, Ehsan Bari, Salman Ahmed, Iqra Patoli

Abstract:

Objective: To determine the value of aPTT, platelets and INR as the predictor of unfavorable outcomes in patients with blunt isolated traumatic brain injury. Methods: This was an observational cohort study conducted in a tertiary care facility from 1st January 2008 to 31st December 2012. All the patients with isolated traumatic brain injury presenting within 24 hours of injury were included in the study. Coagulation parameters at presentation were recorded and Glasgow Outcome Scale calculated on last follow up. Outcomes were dichotomized into favorable and unfavorable outcomes. Relationship of coagulopathy with GOS and unfavorable outcomes was calculated using Spearman`s correlation and area under curve ROC analysis. Results: 121 patients were included in the study. The incidence of coagulopathy was found to be 6 %. aPTT was found to a significantly associated with unfavorable outcomes with an AUC = 0.702 (95%CI = 0.602-0.802). Predictive value of platelets and INR was not found to be significant. Conclusion: Incidence of coagulopathy was found to be low in current population compared to data from the West. aPTT was found to be a good predictor of unfavorable outcomes compared with other parameters of coagulation.

Keywords: aPTT, coagulopathy, unfavorable outcomes, parameters

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1271 The Changing Face of Tourism-Making the Connection through Technological Advancement

Authors: Faduma Ahmed-Ali

Abstract:

The up and coming new generation of travelers will change how the world will achieve its global connectivity. The goal is that through people and technological advancement world-wide, people will be able to better explore the culture and beauty, as well as gain a better understanding of the core values of each host countries treasures. Through Rika's unique world connection model approach, the tourist can explore their destination with the help of local connections. Achieving a complete understanding of the host country while ensuring equal economic prosperity and cultural exchange is key to changing the face of tourism. A recent survey conducted by the author at Portland International Airport shows that over 50% of tourists entering Portland, Oregon are more eager to explore the city through local residents rather than an already planned itinerary created by travel companies. This new model, Rika, aims to shed light to the importance of connecting tourists with the technological tools that increase connectivity to the locals for a better travel experience and that fosters shared economic prosperity throughout a community achieving the goal of creating a sustainable, people driven economy.

Keywords: RIKA, tourism, connection, technology, economic impact, sustainability, hospitality, strategies, tourism development, environment

Procedia PDF Downloads 270
1270 Characterization of Laminar Flow and Power Consumption in Agitated Vessel with Curved Blade Agitator

Authors: Amine Benmoussa, Mohamed Bouanini, Mebrouk Rebhi

Abstract:

Stirring is one of the unifying processes which form part of the mechanical unit operations in process technology such chemical, biotechnological, pharmaceutical, petrochemical, cosmetic, and food processing. Therefore determining the level of mixing and overall behavior and performance of the mixing tanks are crucial from the product quality and process economics point of views. The most fundamental needs for the analysis of these processes from both a theoretical and industrial perspective are the knowledge of the hydrodynamic behavior and the flow structure in such tanks. Depending on the purpose of the operation carried out in mixer, the best choice for geometry of the tank and agitator type can vary widely. Initially, a local and global study namely the velocity and power number on a typical agitation system agitated by a mobile-type two-blade straight (d/D=0.5) allowed us to test the reliability of the CFD, the result were compared with those of experimental literature, a very good concordance was observed. The stream function, the velocity profile, the velocity fields and power number are analyzed. It was shown that the hydrodynamics is modified by the curvature of the mobile which plays a key role.

Keywords: agitated vessels, curved blade agitator, laminar flow, finite volume method

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1269 Effect of Rainflow Cycle Number on Fatigue Lifetime of an Arm of Vehicle Suspension System

Authors: Hatem Mrad, Mohamed Bouazara, Fouad Erchiqui

Abstract:

Fatigue, is considered as one of the main cause of mechanical properties degradation of mechanical parts. Probability and reliability methods are appropriate for fatigue analysis using uncertainties that exist in fatigue material or process parameters. Current work deals with the study of the effect of the number and counting Rainflow cycle on fatigue lifetime (cumulative damage) of an upper arm of the vehicle suspension system. The major part of the fatigue damage induced in suspension arm is caused by two main classes of parameters. The first is related to the materials properties and the second is the road excitation or the applied force of the passenger’s number. Therefore, Young's modulus and road excitation are selected as input parameters to conduct repetitive simulations by Monte Carlo (MC) algorithm. Latin hypercube sampling method is used to generate these parameters. Response surface method is established according to fatigue lifetime of each combination of input parameters according to strain-life method. A PYTHON script was developed to automatize finite element simulations of the upper arm according to a design of experiments.

Keywords: fatigue, monte carlo, rainflow cycle, response surface, suspension system

Procedia PDF Downloads 242
1268 Evaluation of Uniformity for Gafchromic Sheets for Film Dosimetry

Authors: Fayzan Ahmed, Saad Bin Saeed, Abdul Qadir Jangda

Abstract:

Gafchromic™ sheet are extensively used for the QA of intensity modulated radiation therapy and other in-vivo dosimetry. Intra-sheet Non-uniformity of scanner as well as film causes undesirable fluctuations which are reflected in dosimetry The aim of this study is to define a systematic and robust method to investigate the intra-sheet uniformity of the unexposed Gafchromic Sheets and the region of interest (ROI) of the scanner. Sheets of lot No#: A05151201 were scanned before and after the expiry period with the EPSON™ XL10000 scanner in the transmission mode, landscape orientation and 72 dpi resolution. ROI of (8’x 10’ inches) equal to the sheet dimension in the center of the scanner is used to acquire images with full transmission, block transmission and with sheets in place. 500 virtual grids, created in MATALB® are imported as a macros in ImageJ (1.49m Wayne Rasband) to analyze the images. In order to remove the edge effects, the outer 86 grids are excluded from the analysis. The standard deviation of the block transmission and full transmission are 0.38% and 0.66% confirming a higher uniformity of the scanner. Expired and non-expired sheets have standard deviations of 2.18% and 1.29%, show that uniformity decreases after expiry. The results are promising and indicates a good potential of this method to be used as a uniformity check for scanner and unexposed Gafchromic sheets.

Keywords: IMRT, film dosimetry, virtual grids, uniformity

Procedia PDF Downloads 468
1267 Unconventional Strategies for Combating Multidrug Resistant Bacterial Biofilms

Authors: Soheir Mohamed Fathey

Abstract:

Biofilms are complex biological communities which are hard to be eliminated by conventional antibiotic administration and implemented in eighty percent of humans infections. Green remedies have been used for centuries and have shown obvious effects in hindering and combating microbial biofilm infections. Nowadays, there has been a growth in the number of researches on the anti-biofilm performance of natural agents such as plant essential oil (EOs) and propolis. In this study, we investigated the antibiofilm performance of various natural agents, including four essential oils (EOs), cinnamon (Cinnamomum cassia), tea tree (Melaleuca alternifolia), and clove (Syzygium aromaticum), as well as propolis versus the biofilm of both Gram-positive pathogenic bacterium Staphylococcus aureus and Gram-negative pathogenic bacterium Pseudomonas aeruginosa which are major human and animal pathogens rendering a high risk due to their biofilm development ability. The antibiofilm activity of the tested agents was evaluated by crystal violet staining assay and detected by scanning electron and fluorescent microscopy. Antibiofilm performance declared a potent effect of the tested products versus the tested bacterial biofilms.

Keywords: biofilm, essential oils, electron microscopy, fluorescent

Procedia PDF Downloads 77
1266 Impact of Bacillus subtilis Exotoxins on Fecundity, Sex Hormones and Release of Schistosoma mansoni cercariae in Biomphalaria alexandrina Snails

Authors: Alaa A. Youssef, Mohamed A. El-Emam, Momeana B. Mahmoud, Mona Ragheb

Abstract:

Schistosomiasis, also known as bilharzia, is a disease caused by a parasitic trematode worm called Schistosoma. Biological control of the snail intermediate hosts of Schistosoma is one of the promising methods for eliminating this disease in Egypt. The molluscicidal activity of exotoxins secreted from Bacillus subtilis bacteria was studied. The effect of these exotoxins was studied on the fecundity of Biomphalaria alexandrina snails the intermediate host of Schistosoma mansoni; the fecundity includes the reproductive rate (R0) of B. alexandrina snails and levels of sex hormones (progesterone, testosterone, and estradiol). Moreover, the cercarial production of S. mansoni was determined. The results showed a significant reduction in the egg-laying capacity of the treated snails after exposure to sublethal concentrations ( LC10 and LC25) of B. Subtilis exotoxins; this reduction reached 70% at LC25. Moreover, B. Subtilis exotoxins' significantly suppressed the cercarial production of B. alexandrina snails. It is concluded that the exotoxins of Bacillus subtilis bacteria play an important role in the interference of the Schistosomiasis transmission, hence should be applied in the strategy of schistosomiasis control.

Keywords: schistosomiasis, Biomphalaria alexandrina snails, Bacillus subtilis bacteria, fecundity, sex hormones

Procedia PDF Downloads 124
1265 Measuring Delay Using Software Defined Networks: Limitations, Challenges, and Suggestions for Openflow

Authors: Ahmed Alutaibi, Ganti Sudhakar

Abstract:

Providing better Quality-of-Service (QoS) to end users has been a challenging problem for researchers and service providers. Building applications relying on best effort network protocols hindered the adoption of guaranteed service parameters and, ultimately, Quality of Service. The introduction of Software Defined Networking (SDN) opened the door for a new paradigm shift towards a more controlled programmable configurable behavior. Openflow has been and still is the main implementation of the SDN vision. To facilitate better QoS for applications, the network must calculate and measure certain parameters. One of those parameters is the delay between the two ends of the connection. Using the power of SDN and the knowledge of application and network behavior, SDN networks can adjust to different conditions and specifications. In this paper, we use the capabilities of SDN to implement multiple algorithms to measure delay end-to-end not only inside the SDN network. The results of applying the algorithms on an emulated environment show that we can get measurements close to the emulated delay. The results also show that depending on the algorithm, load on the network and controller can differ. In addition, the transport layer handshake algorithm performs best among the tested algorithms. Out of the results and implementation, we show the limitations of Openflow and develop suggestions to solve them.

Keywords: software defined networking, quality of service, delay measurement, openflow, mininet

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1264 Mechanical and Tribological Properties of Al7075 Reinforced with Graphene-Beryl Hybrid Metal Matrix Composites

Authors: Mohamed Haneef, Shanawaz Patil, Syed Zameer, Mohammed Mohsin Ali

Abstract:

The emerging technologies and trends of present generation requires downsizing the unwieldy structures to light weight structures on one hand and integration of varied properties on other hand to meet the application demands. In the present investigation an attempt is made to familiarize and best possibilities of reinforcing agent in aluminum 7075 matrix with naturally occurring beryl (Be) and graphene (Gr) to develop a new hybrid composite material. A stir casting process was used to fabricate with fixed volume fraction of 6wt% weight beryl and various volume fractions of 0.5wt%, 1wt%, 1.5wt% and 2wt% of graphene. The properties such as tensile strength, hardness and dry sliding wear behavior of hybrid composites were examined. The crystallite size and morphology of the graphene and beryl particles were analyzed with X-ray diffraction (XRD) and scanning electron microscopy (SEM) respectively. It was observed that ultimate tensile strength and hardness of the hybrid composite increased with increasing reinforcement volume fraction as compared to specimen without reinforcement additions. The dry sliding wear behavior of the hybrid composites decreases as compared to Al7075 alloy without reinforcement.

Keywords: Al7075, beryl, graphene, TEM, wear

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1263 Comparison Between Nano Composite and Pits and Fissure Sealant: In Vitro Study

Authors: Osama Safwat Mohamed

Abstract:

Pits and fissures dental caries can be prevented using sealant material. This study aimed to compare the microleakage and interfacial morphology of flowable nanocomposites and conventional pit and fissure sealants. 60 extracted intact and caries-free permanent mandibular third molars. The teeth were randomly divided into three groups (n = 20) according to the material used for pit and fissure sealant. Group I: Unfilled resin-based pits and fissure sealant, Group II: Unfilled resin-based pits and fissure sealant with bond and Group III: Nano flowable composite resin with bond. The results showed that nano-flowable composite was significantly better than the conventional sealants groups p = 0.000. As well there was better as well, there were gaps between sealants and the tooth surfaces in groups I and II, but for group III, there was close contact between the nano-flowable composite and tooth surfaces. It was concluded that nano-flowable composite showed better microleakage and interfacial morphology results than conventional pits and fissure sealant and offered promising results at the fissure sealing.

Keywords: pits and fissures, Sealant, nanocomposite, dental caries

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1262 Liquid-Liquid Extraction of Uranium(vi) from Aqueous Solution Using 1-Hydroxyalkylidene-1,1-Diphosphonic Acids

Authors: M. Bouhoun Ali, A. Y. Badjah Hadj Ahmed, M. Attou, A. Elias, M. A. Didi

Abstract:

The extraction of uranium(VI) from aqueous solutions has been investigated using 1-hydroxyhexadecylidene-1,1-diphosphonic acid (HHDPA) and 1-hydroxydodecylidene-1,1-diphosphonic acid (HDDPA), which were synthesized and characterized by elemental analysis and by FT-IR, 1H NMR, 31P NMR spectroscopy. In this paper, we propose a tentative assignment for the shifts of those two ligands and their specific complexes with uranium(VI). We carried out the extraction of uranium(VI) by HHDPA and HDDPA from [carbon tetrachloride + 2-octanol (v/v: 90%/10%)] solutions. Various factors such as contact time, pH, organic/aqueous phase ratio and extractant concentration were considered. The optimum conditions obtained were: contact time= 20 min, organic/aqueous phase ratio = 1, pH value = 3.0 and extractant concentration = 0.3M. The extraction yields are more significant in the case of the HHDPA which is equipped with a hydrocarbon chain, longer than that of the HDDPA. Logarithmic plots of the uranium(VI) distribution ratio vs. pHeq and the extractant concentration showed that the ratio of extractant to extracted uranium(VI) (ligand/metal) is 2:1. The formula of the complex of uranium(VI) with the HHDPA and the DHDPA is UO2(H3L)2 (HHDPA and DHDPA are denoted as H4L). A spectroscopic analysis has showed that coordination of uranium(VI) takes place via oxygen atoms.

Keywords: liquid-liquid extraction, uranium(vi), 1-hydroxyalkylidene-1, 1-diphosphonic acids, hhdpa, hddpa, aqueous solution

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1261 Efficacy of Defender 2% WS (Tebuconazole) and Imidal 70 WS (Imidacloprid) to Control Damping-Off Diseases and Early Insect Pests in Sesame in Rain Fed Areas, Sudan

Authors: Anas Fadlelmula, Elsafi M. M. Ahmed

Abstract:

The efficacy of Defender 2% WS (tebuconazole) and Imidal 70 WS (imidacloprid) to control damping-off diseases and early insect pests in sesame crop under rain fed conditions at Damazine and Gedarif areas was evaluated. Defender 2% WS with dosage rates 0.5, 0.75, 1.0 and 1.25 g/kg of seeds and Imidal 70 WS at 2.25, 3.0, and 3.75 g/ kg of seeds were tested singly and as a mixture during 2010/2011 and 2012/013. Sesame seeds treated with Defender at the rates of 0.5 g and 0.75 g/ kg of seeds gave a high significant increase in percent seedlings emergence (84% and 85%) respectively. Imidal 70 WS at rate of 3g/kg seed showed the least percent damaged leaves by sesame webworm (1.7%). However, the mixed Defender at rate 0.75g with Imidal at 3 g/kg seed, significantly gave a highest percentage of sesame seedling emergence (85.1%) and reduced the incidence of post-emergence damping off and percent damaged leaves to the least per cent (2.1% and 0.4% ) respectively, compared to other treatments. Consequently, the mixed treatment of 0.75 g of Defender + 3 g of Imidal improved the crop stand and significantly gave the highest yield (405.2 kg and 418.8 kg/fed) respectively in both sites compared to the other treatments.

Keywords: seed dressers, damage, daming off, insects

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1260 Dysbiosis of the Intestinal Microbiome in Colorectal Cancer Patients at Hospital of Amizour, Bejaia, Algeria

Authors: Adjebli Ahmed, Messis Abdelaziz, Ayeche Riad, Tighilet Karim, Talbi Melissa, Smaili Yanis, Lehri Mokrane, Louardiane Mustapha

Abstract:

Colorectal cancer is one of the most common types of cancer worldwide, and its incidence has been increasing in recent years. Data and fecal samples from colorectal cancer patients were collected at the Amizour Public Hospital's oncology department (Bejaia, Algeria). Microbiological and cohort study were conducted at the Biological Engineering of Cancers laboratory at the Faculty of Medicine of the University of Bejaia. All the data showed that patients aged between 50 and 70 years were the most affected by colorectal cancer, while the age categories of [30-40] and [40-50] were the least affected. Males were more likely to be at risk of contracting colorectal cancer than females. The most common types of colorectal cancer among the studied population were sigmoid cancer, rectal cancer, transverse colon cancer, and ascending colon cancer. The hereditary factor was found to be more dominant than other risk factors. Bacterial identification revealed the presence of certain pathogenic and opportunistic bacterial genera, such as E. coli, K. pneumoniae, Shigella sp, and Streptococcus group D. These results led us to conclude that dysbiosis of the intestinal microbiome is strongly present in colorectal cancer patients at the EPH of Amizour.

Keywords: microbiome, colorectal cancer, risk factors, bacterial identification

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1259 Molecular Detection and Characterization of Shiga Toxogenic Escherichia coli Associated with Dairy Product

Authors: Mohamed Al-Hazmi, Abdullah Al-Arfaj, Moussa Ihab

Abstract:

Raw, unpasteurized milk can carry dangerous bacteria such as Salmonella, E. coli, and Listeria, which are responsible for causing numerous foodborne illnesses. The objective of this study was molecular characterization of shiga toxogenic E. coli in raw milk collected from different Egyptian governorates by multiplex PCR. During the period of 25th May to 25th October 2012, a total of 320 bulk-tank milk samples were collected from 10 cow farms located in different Egyptian governorates. Bacteriological examination of milk samples revealed the presence of E. coli organisms in 65 samples (20.3%), serotyping of the E. coli isolates revealed, 35 strains (10.94%) O111, 15 strains (4.69%) O157: H7, 10 strains (3.13%) O128 and 5 strains (1.56%) O119. Multiplex PCR for detection of shiga toxin type 2 and intimin genes revealed positive amplification of 255 bp fragment of shiga toxin type 2 gene and 384 bp fragment of intimin gene from all E. coli serovar O157: H7, while from serovar O111 were 25 (71.43%), 20 (57.14%) and from serovar O128 were 6 (60%), 8 (80%), respectively. The results of multiplex PCR assay are useful for identification of STEC possessing the eaeA and stx2 genes.

Keywords: raw milk, E. coli, multiplex PCR, Shiga toxin type 2, intimin gene

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1258 A Computational Fluid Dynamics Study of Turbulence Flow and Parameterization of an Aerofoil

Authors: Mohamed Z. M. Duwahir, Shian Gao

Abstract:

The main objective of this project was to introduce and test a new scheme for parameterization of subsonic aerofoil, using a function called Shape Function. Python programming was used to create a user interactive environment for geometry generation of aerofoil using NACA and Shape Function methodologies. Two aerofoils, NACA 0012 and NACA 1412, were generated using this function. Testing the accuracy of the Shape Function scheme was done by Linear Square Fitting using Python and CFD modelling the aerofoil in Fluent. NACA 0012 (symmetrical aerofoil) was better approximated using Shape Function than NACA 1412 (cambered aerofoil). The second part of the project involved comparing two turbulent models, k-ε and Spalart-Allmaras (SA), in Fluent by modelling the aerofoils NACA 0012 and NACA 1412 in conditions of Reynolds number of 3 × 106. It was shown that SA modelling is better for aerodynamic purpose. The experimental coefficient of lift (Cl) and coefficient of drag (Cd) were compared with empirical wind tunnel data for a range of angle of attack (AOA). As a further step, this project involved drawing and meshing 3D wings in Gambit. The 3D wing flow was solved and compared with 2D aerofoil section experimental results and wind tunnel data.

Keywords: CFD simulation, shape function, turbulent modelling, aerofoil

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1257 SAMRA: Dataset in Al-Soudani Arabic Maghrebi Script for Recognition of Arabic Ancient Words Handwritten

Authors: Sidi Ahmed Maouloud, Cheikh Ba

Abstract:

Much of West Africa’s cultural heritage is written in the Al-Soudani Arabic script, which was widely used in West Africa before the time of European colonization. This Al-Soudani Arabic script is an African version of the Maghrebi script, in particular, the Al-Mebssout script. However, the local African qualities were incorporated into the Al-Soudani script in a way that gave it a unique African diversity and character. Despite the existence of several Arabic datasets in Oriental script, allowing for the analysis, layout, and recognition of texts written in these calligraphies, many Arabic scripts and written traditions remain understudied. In this paper, we present a dataset of words from Al-Soudani calligraphy scripts. This dataset consists of 100 images selected from three different manuscripts written in Al-Soudani Arabic script by different copyists. The primary source for this database was the libraries of Boston University and Cambridge University. This dataset highlights the unique characteristics of the Al-Soudani Arabic script as well as the new challenges it presents in terms of automatic word recognition of Arabic manuscripts. An HTR system based on a hybrid ANN (CRNN-CTC) is also proposed to test this dataset. SAMRA is a dataset of annotated Arabic manuscript words in the Al-Soudani script that can help researchers automatically recognize and analyze manuscript words written in this script.

Keywords: dataset, CRNN-CTC, handwritten words recognition, Al-Soudani Arabic script, HTR, manuscripts

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1256 A Study on the Influence of Aswan High Dam Reservoir Loading on Earthquake Activity

Authors: Sayed Abdallah Mohamed Dahy

Abstract:

Aswan High Dam Reservoir extends for 500 km along the Nile River; it is a vast reservoir in southern Egypt and northern Sudan. It was created as a result of the construction of the Aswan High Dam between 1958 and 1970; about 95% of the main water resources for Egypt are from it. The purpose of this study is to discuss and understand the effect of the fluctuation of the water level in the reservoir on natural and human-induced environmental like earthquakes in the Aswan area, Egypt. In summary, the correlation between the temporal variations of earthquake activity and water level changes in the Aswan reservoir from 1982 to 2014 are investigated and analyzed. This analysis confirms a weak relation between the fluctuation of the water level and earthquake activity in the area around Aswan reservoir. The result suggests that the seismicity in the area becomes active during a period when the water level is decreasing from the maximum to the minimum. Behavior of the water level in this reservoir characterized by a special manner that is the unloading season extends to July or August, and the loading season starts to reach its maximum in October or November every year. Finally, daily rate of change in the water level did not show any direct relation with the size of the earthquakes, hence, it is not possible to be used as a single tool for prediction.

Keywords: Aswan high dam reservoir, earthquake activity, environmental, Egypt

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1255 Correlation of IFNL4 ss469415590 and IL28B rs12979860 with the Hepatitis C Virus Treatment Response among Tunisian Patients

Authors: Khaoula Azraiel, Mohamed Mehdi Abassi, Amel Sadraoui, Walid Hammami, Azouz Msaddek, Imed Cheikh, Maria Mancebo, Elisabet Perez-Navarro, Antonio Caruz, Henda Triki, Ahlem Djebbi

Abstract:

IL28B rs12979860 genotype is confirmed as an important predictor of response to peginterferon/ribavirin therapy in patients with chronic hepatitis C (CHC). IFNL4 ss469415590 is a newly discovered polymorphism that could also affect the sustained virological response (SVR). The aim of this study was to evaluate the association of IL28B and IFNL4 genotypes with peginterferon/ribavirin treatment response in Tunisians patients with CHC and to determine which of these SNPs, was the stronger marker. A total of 120 patients were genotyped for both rs12979860 and ss469415590 polymorphisms. The association of each genetic marker with SVR was analyzed and comparison between the two SNPs was calculated by logistic regression models. For rs12979860, 69.6% of patients with CC, 41.8% with CT and 42.8% with TT achieved SVR (p = 0.003). Regarding ss469415590, 70.4% of patients with TT/TT genotype achieved SVR compared to 42.8% with TT/ΔG and 37.5% with ΔG /ΔG (p = 0.002). The presence of CC and TT/TT genotypes was independently associated with treatment response with an OR of 3.86 for each. In conclusion, both IL28B rs12979860 and IFNL4 ss469415590 variants were associated with response to pegIFN/RBV in Tunisian patients, without any additional benefit in performance for IFNL4. Our results are different from those detected in Sub-Saharan Africa countries.

Keywords: Hepatitis C virus, IFNL4, IL28B, Peginterferon/ribavirin, polymorphism

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