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Rudists(Bivalvia) from a Cretaceous Platform in Northern Egypt: Taxonomy and Paleobiogeography

Acta Geologica Sinica(English Edition) 2021年第6期95卷 1967-1983页

作者： yasser SALAMA Jamaan S.AJAREM Ahmed A.ALLAM Ahmed M.ALMALKI Geology Department Faculty of ScienceBeni-suef UniversityBeni-suef 65211Egypt Department of Zoology College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Department of Zoology Faculty of ScienceBeni-suef UniversityBeni-suef 65211Egypt

New well-preserved rudist materials come from the Barremian–Turonian marine formations in the Yelleg, Minsherah, Maaza, and Raghawi sections in North Sinai, northern Egypt. There, 17 discovered rudist species belonging to 13 genera and seven taxonomic families are described in detail as follows: Eoradiolites plicatus(Conrad), Eoradiolites liratus(Conrad), Praeradiolites ponsianus(d'Archiac), Archaeoradiolites sp., Bournonia africana Douvillé, Bournonia fourtaui Douville, Biradiolites lombricalis(d'Orbigny), Biradiolites zumoffeni Douville, Radiolites lewyi lewyi Parnes, Radiolites sauvagesi(d'Hombres-Firmas), Durania arnaudi(Choffat), Toucasia carinata(Matheron), Toucasia sp., Neocaprina raghawiensis Steuber and Bachmann, Sellaea sp., Ichthyosarcolites sp. and Horoiopleura sp.. The Cenomanian deposits in the northern Eastern desert of Egypt only contain E. liratus. The domination of the Cenomanian rudist species in North Sinai, however, is attributed to changes in the platform, which passes mainly from carbonate in the north to siliciclastics in the south. The presence of Horiopleura sp. in the late Barremian-early Aptian deposits is documented for the first time, which suggests the expansion of taxa of the genus Horiopleura Douville to North Sinai during this interval. The age of the rudist species is documented from the late Barremian-Turonian formations, with their geographic distribution in the Mediterranean region considered..

关键词： invertebrate paleontology mollusks rudists Taxonomy Paleobiogeography Barremian–Turonian Egypt

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Database Recovery Technique for Mobile Computing:A Game Theory Approach

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Computers, Materials & Continua 2022年第2期70卷 3205-3219页

作者： Magda M.Madbouly yasser F.Mokhtar Saad M.Darwish Institute of Graduate Studies and Research Alexandria UniversityAlexandriaEgypt Assistant General Manager IT DepartmentEgyptian Petrochemicals Co.AlexandriaEgypt

Contact between mobile hosts and database servers presents many problems in theMobile Database System(MDS).It is harmed by a variety of causes,including handoff,inadequate capacity,frequent transaction updates,and repeated failures,both of which contribute to serious issues with the information system’s ***,error tolerance technicality allows devices to continue performing their functions in the event of a *** aim of this paper is to identify the optimal recovery approach from among the available state-of-the-art techniques in MDS by employing game *** of the presented recovery protocols are chosen and evaluated in order to determine the most critical factors affecting the recovery mechanism,such as the number of processes,the time required to deliver messages,and the number of messages logged-in ***,using the suggested payout matrix,the game theory strategy is adapted to choose the optimum recovery technique for the specified environmental *** NS2 simulatorwas used to carry out the tests and apply the chosen recovery *** experiments validate the proposed model’s usefulness in comparison to other methods.

关键词： Mobile computing game theory decision making mobile database recovery

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DeepSun:machine-learning-as-a-service for solar flare prediction

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Research in Astronomy and Astrophysics 2021年第7期21卷 51-61页

作者： yasser Abduallah Jason T.L.Wang Yang Nie Chang Liu Haimin Wang Institute for Space Weather Sciences New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA Department of Computer Science New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA Big Bear Solar Observatory New Jersey Institute of Technology40386 North Shore LaneBig Bear CityCA 92314-9672USA Center for Solar-Terrestrial Research New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA

Solar flare prediction plays an important role in understanding and forecasting space *** main goal of the Helioseismic and Magnetic Imager(HMI), one of the instruments on NASA's Solar Dynamics Observatory, is to study the origin of solar variability and characterize the Sun's magnetic *** provides continuous full-disk observations of the solar vector magnetic field with high cadence data that lead to reliable predictive capability;yet, solar flare prediction effort utilizing these data is still limited. In this paper, we present a machine-learning-as-a-service(MLaa S) framework, called Deep Sun,for predicting solar flares on the web based on HMI's data products. Specifically, we construct training data by utilizing the physical parameters provided by the Space-weather HMI Active Region Patch(SHARP)and categorize solar flares into four classes, namely B, C, M and X, according to the X-ray flare catalogs available at the National Centers for Environmental Information(NCEI). Thus, the solar flare prediction problem at hand is essentially a multi-class(i.e., four-class) classification problem. The Deep Sun system employs several machine learning algorithms to tackle this multi-class prediction problem and provides an application programming interface(API) for remote programming users. To our knowledge, Deep Sun is the first MLaa S tool capable of predicting solar flares through the internet.

关键词： Sun:flares Sun:activity methods:data analysis

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On-chip parallel Fourier transform spectrometer for broadband selective infrared spectral sensing

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Microsystems & Nanoengineering 2020年第1期6卷 1267-1275页

作者： Alaa Fathy yasser M.Sabry Sebastien Nazeer Tarik Bourouina Diaa A.Khalil Faculty of Engineering Ain-Shams University1 Elsarayat St.AbbassiaCairoEgypt Si-Ware Systems 3 Khalid Ibn Al-Waleed St.HeliopolisCairoEgypt UniversitéParis-Est ESYCOM EA 2552ESIEE Paris93162 Noisy-le-GrandFrance

Optical spectrometers enable contactless chemical ***,decreasing both their size and cost appears to be a prerequisite to their widespread ***-scale implementation of optical spectrometers still requires tackling two main ***,operation over a broad spectral range extending to the infrared is required to enable covering the molecular absorption spectrum of a broad variety of *** is addressed in our work with an Micro-Electro Mechanical Systems(MEMS)-based Fourier transform infrared spectrometer with an embedded movable micro-mirror on a silicon ***,fine spectral resolutionΔλis also required to facilitate screening over several chemicals.A fundamental limit states thatΔλis inversely proportional to the mirror motion range,which cannot exceed the chip *** boost the spectral resolution beyond this limit,we propose the concept of parallel(or multi-core)FTIR,where multiple interferometers provide complementary optical paths using the same actuator and within the same *** concept scalability is validated with 4 interferometers,leading to approximately 3 times better spectral *** the atmospheric contents of a greenhouse gas are monitored,the methane absorption bands are successfully measured and discriminated using the presented device.

关键词： interferometer spectral mirror

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Influence of the pH,Pretreatment and Hydraulic Retention Time on the Enhancement of the Biohydrogen and Volatile Fatty Acids Production from Food Waste in the Semi-continuously Running Reactor

Influence of the pH,Pretreatment and Hydraulic Retention Tim...

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作者： REHAM yasser FAROUK HAMED 华中农业大学

学位级别：硕士

食物垃圾(FW)是一种未开发的资源,具有很高的资源回收能力。在暗发酵(DF)中使用FW作为底物被广泛研究,因为FW含有大量有机物质和水分,如脂质、淀粉和蛋白质。暗发酵具有从食物垃圾中生产高价值副产物生产的能力,如乳酸(LA),氢(H2),醇(Et... 详细信息

食物垃圾(FW)是一种未开发的资源,具有很高的资源回收能力。在暗发酵(DF)中使用FW作为底物被广泛研究,因为FW含有大量有机物质和水分,如脂质、淀粉和蛋白质。暗发酵具有从食物垃圾中生产高价值副产物生产的能力,如乳酸(LA),氢(H2),醇(EtOH),短链脂肪酸和甲烷。此外,已经证明氢是有前景的能源之一,对减少对化石燃料的依赖至关重要。另外,VFA也被广泛应用,如作为替代碳源的利用。本研究采用中温半连续的反应器系统,以食品垃圾废水为底物进行产氢和挥发性脂肪酸VFAs,研究PHP(预处理、HRT和pH)系统对氢和挥发性脂肪酸(VFA)产生的影响。另外,将PHP和非调控的系统进行比较。首先研究了酸碱度和预处理的影响。通过重复SAS分析表明,这些因素(酸碱度和预处理)对H2产率、VFA浓度、VFA/可溶性化学耗氧量(SCOD)和H2/SCOD这些指标有显著影响(P<0.0001)。邓肯比较表明,在pH=7条件下,化学处理(CT)的H2产率和产量最高,而在pH=6时,化学处理(CT)组的VFA产量和浓度最高,VFA浓度为55.44±2.39 g/L,产率为926.21±42.27mg/g SCOD,此时 H2 产量为 280.82±5.72 ml/L,产率为 4.44±0.10ml/g SCOD。最佳条件时(pH=6,CT预处理)发酵液中的丁酸盐和乙酸盐含量占总挥发性脂肪酸VFAs总量的62.43%。另一方面,实验结果表明,pH=5对H2和VFA的生成没有显著促进作用。此外,在pH=7和CT预处理的基础之上,本课题研究了水力停留时间(HRT)对发酵过程的影响。其中三种不同的HRT(2d、3d和4d)用于评估其对氢和VFA生产的影响。单因素方差分析表明,HRT对H2的产量和产率有显著影响,而在HRT=3d时出现H2的最高产量和产率,分别为263.82±18.44,5.19±0.40 ml/g SCOD。相反,HRT对VFA的产率无显著影响,当HRT在2d到4d内变化时,VFA浓度在36.03±1.72至40.19±1.53 g/L范围内波动。但是HRT对VFA的浓度有显著影响,在HRT=2d时VFA浓度达到最高值40.19±1.53 g/L。本实验产物以丁酸盐为主,占总VFA的50%。另外,结果表明,HRT=2d时的H2和VFA产量最低。通过聚合酶链反应(PCR)的变性梯度凝胶电泳(DGGE)-在16S rDNA分析的扩增的V3-V4区域,在所有HRT水平上均检测出产氢和产VFA的菌种。结果表明,微生物的高度多样性为HRT2,其具有最高的氢产率和VFA浓度。所检测出来的主要菌种是乳酸杆菌,事实证明,乳酸杆菌不会影响氢的产生,而梭菌属是产氢所必需的菌种。同时本研究发现,丁酸梭菌的存在是形成丁酸盐发酵的主要原因。此外,还对同一 HRT条件下PHP系统与非调控系统进行了比较研究。配对样本T检验表明,PHP系统与非调控系统对氢气和VFA的产生有显著性差异(P<0.0001)。非调控系统的氢气产率为0.19ml/L,PHP系统的氢气产率升高至263.82ml/L。PHP系统的VFA产量比非调控系统高1.8倍,因此PHP是一种可以提高H2和VFA产量的较为理想的工艺。

关键词：生物制氢餐厨垃圾挥发性脂肪酸 pH HRT 预处理

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Fatigue Life Estimation of High Strength 2090-T83 Aluminum Alloy under Pure Torsion Loading Using Various Machine Learning Techniques

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Fluid Dynamics & Materials Processing 2023年第8期19卷 2083-2107页

作者： Mustafa Sami Abdullatef Faten NAlzubaidi Anees Al-Tamimi yasser Ahmed Mahmood Electromechanical Engineering Department University of Technology-IraqBaghdadIraq

The ongoing effort to create methods for detecting and quantifying fatigue damage is motivated by the high levels of uncertainty in present fatigue-life prediction approaches and the frequently catastrophic nature of fatigue *** fatigue life of high strength aluminum alloy 2090-T83 is predicted in this study using a variety of artificial intelligence and machine learning techniques for constant amplitude and negative stress ratios(R?1).Artificial neural networks(ANN),adaptive neuro-fuzzy inference systems(ANFIS),support-vector machines(SVM),a random forest model(RF),and an extreme-gradient tree-boosting model(XGB)are trained using numerical and experimental input data obtained from fatigue tests based on a relatively low number of stress *** particular,the coefficients of the traditional force law formula are found using relevant numerical *** is shown that,in comparison to traditional approaches,the neural network and neuro-fuzzy models produce better results,with the neural network models trained using the boosting iterations technique providing the best *** strong models from weak models,XGB helps to predict fatigue life by reducing model partiality and variation in supervised *** neural models can be used to predict the fatigue life of alloys more accurately than neural networks and traditional methods.

关键词： Fatigue life high strength aluminum alloy 2090-T83 neuro-fuzzy tree boosting model neural networks adaptive neuro-fuzzy inference systems random forest support vector machines

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Rerouting end-face-TIR capable rays to significantly increase evanescent wave signal power

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Chinese Optics Letters 2011年第4期9卷 18-20页

作者： Jianjun Ma yasser Chiniforooshan Huacai Chen Jiahua Chen Wojtek J. Bock Andrea Cusano Centre de Recherche en Photonique Departement d'informatique et d'ingenierie Universite du Quebec en Outaouais Gatineau Quebec JSX 3X7 Canada College of Optical and Electronic Technology China Jiliang University Hangzhou 310018 China Optoelectronic Division Engineering Department University of Sannio Benevento Italy

The critical findings associated with end-face total internal reflection （TIR） phenomemon we proved before are reported. In particular, these findings reveal that the end-face-TIR capable rays experience enormous mode mixing when encountering a roughened end face. As a result, 94% of the overall detectable power is contributed by this effect. With a smooth fiber end face, this figure is mere 52%. We interpret the mechanism behind these unusual phenomena and its significance for the performance enhancement of fiber optic evanescent wave sensor.

关键词： Refractive index

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Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies

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Hepatobiliary & Pancreatic Diseases International 2022年第4期21卷 334-339页

作者： Maren Schulze yasser Elsheikh Markus Ulrich Boehnert Yasir Alnemary Saleh Alabbad Dieter Clemens Broering Organ Transplant Center of Excellence King Faisal Specialist Hospital&Research CentreP.O.Box 3354Riyadh 11211Saudi Arabia

Background:Over the past two decades robotic surgery has been introduced to many areas including liver *** liver surgery is an alternative minimally invasive ***,moving on to the complexity of living donor hepatectomies,the advantages of robotic versus laparoscopic approach have convinced us to establish the robotic platform as a standard for living donor ***:From November 2018 to January 2022,501 fully robotic donor hepatectomies,including 177 left lateral donor lobes,112 full left lobes and 212 full right lobes were *** were donated to 296 adult recipients and 205 pediatric *** age,sex,body weight,body mass index(BMI),graft weight,graft to body weight ratio(GBWR),operative time,blood loss,first warm ischemic time,pain score,length of intensive care unit(ICU)stay and hospital stay,and complications were retrospectively analyzed based on a prospectively kept *** were evaluated for graft and patient survival,age,sex,BMI,body weight,model of end-stage liver disease score,blood loss,transfusions,operative time,cold ischemic time,length of hospital stay and ***:There was no donor *** cases needed to be converted to open *** median blood loss was 60 mL(range 20-800),median donor operative time was 6.77 h(range 2.93-11.53),median length of hospital stay was 4 days(range 2-22).Complication rate in donors classified following ClavienDindo was 6.4%(n=32)with one grade Ⅲ ***-year actual recipient overall survival was 91.4%;87.5% for adult recipients and 97.1% for pediatric ***-year actual graft overall survival was 90.6%;87.5% for adult recipients and 95.1% for pediatric ***-hospital mortality was 6%,9.1%(27/296)for adult recipients and 1.4%(3/205)for pediatric *** recipients’morbidity was 19.8%(n=99).Twenty-eight recipients(5.6%)had biliary and 22(4.4%)vascular ***(12.0%)recipients needed to

关键词： Living liver donor Innovation Robotic donor surgery Donor safety Minimally invasive donor surgery

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The Role of Chest X-Ray in Monitoring Lung Changes among COVID-19 Patients in Gaza Strip

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Open Journal of Medical Imaging 2021年第2期11卷 29-47页

作者： Mahmoud Mousa Marwan Matar yasser Al Ajerami Ahmad Naijm Khalid Abu Shab Sadi Jaber fouad SJaber Hazem Dawoud Department of Radiology Gaza-European Hospital Gaza Strip Palestine Department of Medical Imaging Applied Medical Sciences Al-Azhar University Gaza Strip Palestine Department of Nursing Applied Medical Sciences Al-Azhar University Gaza Strip Palestine Department of Radiology Nasser Medical Complex Gaza Strip Palestine Valley Fever Institute UCLA Kern Medical Bakersfield USA Department of Chemistry and Biochemistry Ohio University Athens USA

Objective: To investigate the time course and findings severity of COVID-19 infection at chest radiography based on a 6-point radiological severity score, and correlates these with patients’ age and gender. Methods: This is a retrospective study of COVID-19 patients who were admitted at European Gaza Hospital and evaluated between October 6, 2020, and November 30, 2020. Baseline and serial chest radiographs, up to 4 images per patient, were reviewed and assessed for predominant pattern, side, and location of lung opacity. Utilized a 6-point scoring system, which divides the chest X-ray into 6 zones, to assess chest X-ray changes and correlate them with the severity of infection, age, and gender of patients. Results: The study included 136 COVID-19 patients: (51/136, 37%) were males and (85/136, 62.5%) were females, while age ranged from 7 months to 90 years with a mean age of 41.7 ± (19.5) years. Negative Chest x-rays were more observed than positive images. Ground-glass opacity was the most frequent pattern with a decreasing trend from 1st to 4th chest X-ray (from 33.8% to 3.7%), followed by consolidation (from 16.2% to 2.9%). Also, the commonest pattern of opacity was seen in peripheral areas (27/136, 19.9%), lower zone location (23/136, 16.9%), and bilateral opacity involvement (43/136;31.6%). No significant correlation was noticed between the patient’s gender, age, and severity score (P > 0.05). Conclusions: The 6-point chest X-ray severity score as a predictive tool in assessing the severity due to provide an assessment of the progression or regression pathway.

关键词： Chest X-Rays COVID 19 Lung Changes Scoring System Gaza Strip

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Irrigation and Thermal Buffering Using Mathematical Modeling

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Journal of Environmental & Earth Sciences 2024年第1期6卷 19-32页

作者： Yara yasser Elborolosy Harsho Sanyal Joseph Cataldo The Albert Nerken School of Engineering at the Cooper Union New YorkNY 10003US

Two methods of irrigation,drip,and sprinkler were studied to determine the response of the Javits green roof to *** control study was dry unirrigated *** irrigation consisted of irrigation tubes running through the green roof that would water the soil throughout and sprinkler irrigation used a sprinkler system to irrigate the green roof from *** all cases,the irrigated roofs had increased the soil moisture,reduced temperatures of both the upper and lower surfaces,reduced growing medium temperatures and reduced air temperatures above the green roof relative to the unirrigated *** buffered temperature fluctuations were also studied via air conditioner energy *** was a 28%reduction in air conditioner energy consumption and a 33%reduction in overall energy consumption between dry and irrigated *** of thermal resistance or S were determined for accuracy and for this study,there was little change which is ideal.A series of infra-red and thermal probe measurements were used to determine temperatures in the air and *** was determined that the sprinkler irrigation did a better job than the drip irrigation in keeping cooler temperatures within the green roof.A Mann-Whitney U test was performed to verify the variation in moisture temperatures buffering energy *** getting a p-value<0.05,it indicates that the model is accurate for prediction and medium temperatures were statistically different.

关键词： Green roofs Irrigation Drip Sprinkler Thermal buffering

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