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Study of Luminous Emission from a Coaxial Plasma Discharge Device in the Presence of External Transverse magnetic Field

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Energy and Power Engineering 2011年第4期3卷 444-449页

作者： tarek m. Allam Hanaa A. El-Sayed Hanaa m. Soliman 不详

The experimental investigations in this paper are focused on the study of luminous radiation emission from coaxial plasma discharge device and the effect of applied transverse magnetic field Btr on it. The experiment was done in (1.5 KJ - 10 KV) coaxial plasma discharge device. The discharge is operated in Nitrogen gas at pressures from 1 to 2.2 torr. Helmholtz magnetic coils are placed outside the coaxial electrodes with its axis at a distance = 3 cm from the coaxial electrodes muzzle, then Btr with a maximum induction ≈ 0.85 T is applied perpendicularly to the expanded plasma from the coaxial electrodes muzzle. The diagnostics used in the measurements include a Rogowsky coil and a photomultiplier tube equipped with light collimator. The experimental results showed that the maximum intensity of luminous radiation is detected at axial distance (side view) z = 8 cm and gas pressure, P = 2.2 torr. It also showed that the maximum value of axial luminous plasma zone velocity = 2.383 × 106 cm/s at z = 11 cm and P = 1.4 torr. In mode of presence of external Btr, the investigations have shown that, at P = 1.4 torr the maximum intensity of luminous radiation (detected at end-view position) is reduced by 17%, the full width at half maximum, FWHm of luminous radiation signal is increased by 40 times, while the luminous radiation signal is delayed by ta = 438 μs. In two modes of operation ta and FWHm have approximately a minimum values at P = 1.4 torr.

关键词： Coaxial Discharge Luminous Radiation Transverse magnetic Field Energy Losses

The Effect of Starvation on the Biochemical Composition of the Digestive Gland, the Gonads and the Adductor muscle of the Scallop Flexopectenglaber

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Food and Nutrition Sciences 2013年第4期4卷 405-413页

作者： Khaoula Telahigue tarek Hajji Imen Rabeh m’hamed El Cafsi Research Unit of Physiology and Aquatic Environment Faculty of Sciences of Tunis University of Tunis El Manar Tunis Tunisia

The effects of the starvation trial on the biochemical composition and the fatty acid dynamics in the triacylglycerol fraction of the digestive gland, gonads and adductor muscle of the scallop Flexopecten glaber were assessed. Results show that three weeks of food deprivation induce depletion of carbohydrates and a significant decrease in proteins and lipids. The noteworthy patterns recorded for the various classes of lipids were the increase of the amount of phosphatidylethanolamine against a strong decline of mono-diacylglycerols, triacylglycerol and phosphatidylserine classes in gonads. These results reflect the ability of Flexopecten glaber to remodel endogenous lipid classes in order to avoid the gonads deterioration. In the starved specimens, severe declines of the n-3 polyunsaturated fatty acid group were recorded in the triacylglycerol fraction of digestive gland and adductor muscle against the increase of this group in gonads. These results confirm the role of triacylglycerol as a polyunsaturated fatty acids reservoir and pointed out to their mobilization from storage organs to the developing gonads during the food shortage trial. Examination of fatty acid data revealed that food deprivation lead Flexopecten glaber to invest in saving and accumulation of highly unsaturated fatty acids in gonads. This applies mainly to the arachidonic acid (20:4n-6) and the docosahexaenoic acid (22:6n-3).

关键词： Starvation Scallop Chemical Composition Organs Fatty Acid

The Effect of Core Eccentricity on the Structural Behavior of Concrete Tall Buildings

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Journal of Civil Engineering and Architecture 2024年第3期18卷 112-117页

作者： tarek Anwar Taha Awida Civil and Architecture Engineering Department College of EngineeringInternational University of Kuwait(IUK)Ardiya Government AreaKuwait

The main purpose of this paper is to investigate the effect of core eccentricity on the structural behavior of concrete tall *** buildings of 55 floors with plan dimensions 48.0×48.0 m2 were *** cases of main core locations are studied:centric(A),eccentric by one sixth(B)and one third(C)of building *** three-dimensional finite element method has been used in conducting structural analysis through ETABS *** and lateral(wind and seismic)loadings are applied to all building *** has been concluded that the core location is the prime parameter governing the structural behavior of tall *** the first two cases(A,B)have acceptable and similar structural behaviors conforming to code limits,in the third case(C),the building behavior came beyond code *** author introduced remedial action by adding two secondary cores in the opposite direction of the main core(C-R)to restore the building behavior to the code *** results of this action were satisfactory.

关键词： Concrete tall buildings core eccentricity structural behavior gravity wind seismic loadings

Intelligent Sign multi-Language Real-Time Prediction System with Effective Data Preprocessing

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Journal of Computer and Communications 2023年第10期11卷 120-134页

作者： Doaa E. Elmatary Doaa m. maher Areeg tarek Ibrahim Department of Communications and Computers AlSafwa High Institute of Engineering Qalyubia Egypt

A multidisciplinary approach for developing an intelligent sign multi-language recognition system to greatly enhance deaf-mute communication will be discussed and implemented. This involves designing a low-cost glove-based sensing system, collecting large and diverse datasets, preprocessing the data, and using efficient machine learning models. Furthermore, the glove is integrated with a user-friendly mobile application called “Life-sign” for this system. The main goal of this work is to minimize the processing time of machine learning classifiers while maintaining higher accuracy performance. This is achieved by using effective preprocessing algorithms to handle noisy and inconsistent data. Testing and iterating approaches have been applied to various classifiers to refine and improve their accuracy in the recognition process. Additionally, the Extra Trees (ET) classifier has been identified as the best algorithm, with results proving successful gesture prediction at an average accuracy of about 99.54%. A smart optimization feature has been implemented to control the size of data transferred via Bluetooth, allowing for fast recognition of consecutive gestures. Real-time performance has been measured through extensive experimental testing on various consecutive gestures, specifically referring to Arabic Sign Language (ArSL). The results have demonstrated that the system guarantees consecutive gesture recognition with a lower delay of 50 milliseconds.

关键词： Hand Gesture Translator Sign multi-Language machine Learning models Deaf-mute Community

Novel Cascade Refrigeration Cycle for Cold Supply Chain of COVID-19 Vaccines at Ultra-Low Temperature -80°C Using Ethane (R170) Based Hydrocarbon Pair

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World Journal of Engineering and Technology 2021年第2期9卷 309-336页

作者： tarek A. mouneer Abdelrahman m. Elshaer mohamed H. Aly mechanical Engineering Department Benha Faculty of Engineering Benha University Benha Egypt mechanical Power Engineering Department Faculty of Engineering Helwan University Cairo Egypt

Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80°C to transport and store its COVID-19 vaccines. This research presents the thermodynamic analysis on cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, and the hydrocarbon (HC) refrigerant pair Propane/Ethane, namely R290/R170. Besides, the results of R22/R170 pair, which is not recommended to be used due to phase out of R22 as per montréal Protocol, are included as base case to compare the novel hydrocarbon pairs in CRS and the old trend of refrigerant pairs. Thermodynamic properties of all these pairs were investigated and compared under different intermediate temperature used in CRS heat exchanger, which thermally connected both the Low and High temperature cycles (LTC) and (HTC). By applying the first law of thermodynamics, the coefficients of performance (COPs) and the specific power consumptions (SPC) in kW/TR are presented and compared. In addition, by applying the second law of thermodynamics the exergetic efficiencies were estimated. The results reveal the promising opportunity of using the HC pair (R290/R170). The minimum SPC in kW/TR is recorded for the pair R123/R170. One the other hand, the highest exegetic efficiency values are observed to be 40%, 38%, and 35% for the pairs R123/R170, R290/R170, and R134/R170, respectively. This research concludes that the HC pair (R290/R170) is highly recommended for CRS applications either to transport the COVID-19 or store it in cold storage rooms in hospitals and clinics. All precautionary measures should be carefully applied in design and operation of HC pair (R290/R170) due to its flammability hazard.

关键词： Cascade Refrigeration Cold Supply Chain COVID-19 Vaccine Ultra-Low Temperature -80°C Hydrocarbon Refrigerants Refrigerant Pair

Steady State Simulation of a Novel Process for the Co-production of Vinyl Acetate and Acetic Acid

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Journal of Chemistry and Chemical Engineering 2011年第1期5卷 30-36页

作者： Hadir Wahid Fawzy Fouad tarek m. moustafa Ahmed Soliman Department of Chemical Engineering Cairo University Egypt

A new process for the co-production of vinyl acetate monomer and acetic acid from ethane feedstock was studied. Various configurations were proposed and simulation results were given for each case to optimize process variables. This new process offers an overall yield values above 70% with minimum separation steps involved and the possibility of utilities integration. The process does not involve any CO production, thus becoming environmentally more favorable. The initial capital investment of the proposed process is much lower compared to the conventional route.

关键词： Vinyl acetate acetic acid ethane ethylene.

Impact of cirrhosis on surgical outcome after pancreaticoduodenectomy

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World Journal of Gastroenterology 2013年第41期19卷 7129-7137页

作者： Ayman El Nakeeb Ahmad m Sultan tarek Salah mohamed El Hemaly Emad Hamdy Ali Salem Ahmed moneer Rami Said Ahmed AbuEleneen mostafa Abu Zeid Talaat Abdallah mohamed Abdel Wahab Gastroenterology surgical center Mansoura UniversityMansoura 35516Egypt

AIm:To elucidate surgical outcomes of pancreaticoduodenectomy(PD)in patients with liver ***:We studied retrospectively all patients who underwent PD in our centre between January 2002and December *** A comprised patients with cirrhotic livers,and Group B comprised patients with non-cirrhotic *** cirrhotic patients had ChildPugh classes A and B(patient’s score less than 8).Preoperative demographic data,intra-operative data and postoperative details were *** primary outcome measure was hospital mortality *** outcomes analysed included duration of the operation,postoperative hospital stay,postoperative morbidity and survival ***:Only 67/442 patients(15.2%)had cirrhotic *** blood loss and blood transfusion were significantly higher in group A(P=0.0001).The mean surgical time in group A was significantly longer than that in group B(P=0.0001).Wound complications(P=0.02),internal haemorrhage(P=0.05),pancreatic fistula(P=0.02)and hospital mortality(P=0.0001)were significantly higher in the cirrhotic *** stay was significantly longer in group A(P=0.03).The median survival was 19 mo in group A and 24 mo in group *** hypertension(PHT)was present in 16/67 cases of cirrhosis(23.9%).The intraoperative blood loss and blood transfusion were significantly higher in patients with PHT(P=0.001).Postoperative morbidity(0.07)and hospital mortality(P=0.007)were higher in cirrhotic patients with ***:Patients with periampullary tumours and well-compensated chronic liver disease should be routinely considered for PD at high volume centres with available expertise to manage liver *** is associated with an increased risk of postoperative morbidity in patients with liver cirrhosis;therefore,it is only recommended in patients with Child A cirrhosis without portal hypertension.

关键词： Periampullary tumour Liver cirrhosis Portal hypertension Pancreaticoduodenectomy

Protein seeding in Alzheimer's disease and Parkinson's disease: Similarities and differences

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World Journal of Neurology 2014年第4期4卷 23-35页

作者： tarek Ibrahim JoAnne mcLaurin Sunnybrook Research Institute and Department of Laboratory medicine and Pathobiology University of Toronto Toronto M4N 3M5 Canada

Neurodegenerative pathology can be seeded by introduction of misfolded proteins and peptides into the nervous system. models of Alzheimer's disease(AD) and Parkinson's disease(PD) have both demonstrated susceptibility to this seeding mechanism, emphasizing the role of misfolded conformations of disease-specific proteins and peptides in disease progression. Thinking of the amyloidogenic amyloid-beta peptide(Aβ) and alpha-synuclein(α-syn), of AD and PD, respectively, as prionoids requires a comparison of these molecules and the mechanisms underlying the progression of disease. Aβ and α-syn, despite their size differences, are both natively unstructured and misfold into β-structured conformers. Additionally, several studies implicate the significant role of membrane interactions, such as those with lipid rafts in the plasma membrane, in mediating protein aggregation and transfer of Aβ and α-syn between cells that may be common to both AD and PD. Examination of inter-neuronal transfer of proteins/peptides provides evidence into the core mechanism of neuropathological propagation. Specifically, uptake of aggregates likely occurs by the endocytic pathway, possibly in response to their formation of membrane pores via a mechanism shared with pore-forming toxins. Failure of cellular clearance machinery to degrade misfolded proteins favours their release into the extracellular space, where they can be taken up by directly connected, nearby neurons. Although similarities between AD and PD are frequent and include mechanistically similar transfer processes, what differentiates these diseases, in terms of temporal and spatial patterns of propagation, may be in part due to the differing kinetics of protein misfolding. Several examples of animal models demonstrating seeding and propagation by exogenous treatment with Aβ and α-syn highlight the importance of both the environment in which these seeds are formed as well as the environment into which the seeds are propagated. Although

关键词： Alzheimer’s disease Parkinson’s disease Prionoid Seeding Propagation Protein misfolding

Existence Theorem for a Nonlinear Functional Integral Equation and an Initial Value Problem of Fractional Order in L1(R+)

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Applied mathematics 2013年第2期4卷 402-409页

作者： Ibrahim Abouelfarag Ibrahim tarek S. Amer Yasser m. Aboessa mathematics Department Faculty of Science and Education Taif University Al-Khurmah Branch Taif KSA

The aim of this paper is to study the existence of integrable solutions of a nonlinear functional integral equation in the space of Lebesgue integrable functions on unbounded interval, L1(R+). As an application we deduce the existence of solution of an initial value problem of fractional order that be studied only on a bounded interval. The main tools used are Schauder fixed point theorem, measure of weak noncompactness, superposition operator and fractional calculus.

关键词： Nonlinear Functional Integral Equation Volterra Operator measure of Weak Noncompactness Fractional Calculus Schauder Fixed Point Theorem