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Comparative studies on numerical sensitivity of different scenarios of enhanced oil recovery by water-alternating-gas(CO_(2))injection

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Petroleum Research 2023年第4期8卷 505-513页

作者： Saddam Mohammed Mohammed nasser Achinta Bera Vivek Ramalingam School of Energy Technology Pandit Deendayal Energy UniversityGandhinagarGujarat382007India

Enhanced oil recovery by CO_(2) injection technology(CO_(2)-EOR)plays a crucial role in enhancing oil production and the permanent sequestration of anthropogenic CO_(2) in depleted oil ***,the availability of CO_(2) in oil field locations and its mobility in contrast with reservoir fluids are prime challenges in CO_(2)-*** cost of CO_(2) and its availability at the oil fields has prompted investigations on efficient injection of CO_(2) at the fields to achieve the best sweep efficiency *** strategies such as water-alternating-gas(WAG),simultaneous vertical and horizontal WAG,simultaneous water injection into the aquifer and vertical WAG,water and gas injection simultaneously but separately(SS-WAG),and water and gas injection simultaneously but not separately(SNS-WAG)play a significant role,as well as the purity of CO_(2).In this work,the significance of the above criteria was investigated indi-vidually and in *** coupled sequence of injection rate,soaking time,WAG ratio,and purity of injected CO_(2) for enhancement of oil production were delineated.A realistic reservoir simulation model conceptualizing the CO_(2)-EOR system with five spot injection patterns was developed by the company *** history-matched model that was developed was used to investigate the sensitivity of the coupled effects to the criteria listed above on oil *** investigations quantitatively emphasized that purity and soaking time of CO_(2) have an inverse effect in the oil production rate and that SNS-WAG resulted in a better oil production rate than SS-WAG.

关键词： Water-alternating-gas Enhanced oil recovery Sensitivityanalysis Modelingand simulation Simultaneouslybut not separately water-alternating-gas(SS-WAG) Simultaneously pressure maintenance and WAG

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In vitro Evaluation of Seed Germination in Twelve Alfalfa Cultivars under Salt Stress

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Phyton-International Journal of Experimental Botany 2023年第1期92卷 111-120页

作者： Walid Soufan Yaser Hassan Dewir nasser A.Al-Suhaibani Plant Production Department College of Food and Agriculture SciencesKing Saud UniversityRiyadh11451Saudi Arabia

Alfalfa(Medicago sativa L.),when exposed to abiotic stress such as salinity,suffers significant losses in yield and *** present study evaluated the salinity tolerance of 12 alfalfa cultivars in vitro using five concentrations of sodium chloride(NaCl),ranging from 0 to 250 mmol L^(−1).The results obtained in the current study revealed that the Saudi cultivars,Kasimi and Hassawi,and the German cultivar(Berlin)had the highest salinity tolerance in terms of germination percentage(GP),corrected germination rate index(CGRI),days to reach 50%germination(GT_(50)),and ability to form cotyledonary and true *** mmol L^(−1) NaCl,the Saudi cultivar Kasimi cultivar showed GP,CGRI,and GT_(50) of 55.20%,123.15,and 3.77 days,***,the German cultivar(Berlin)showed GP,CGRI,and GT_(50) of 50.06%,86.61,and 5.17 days,*** findings might reveal a pivotal aspect in salt tolerance in *** results will help to select salt-tolerant alfalfa cultivars that could thrive in arid and semi-arid areas with salinity problems.

关键词： Medicago sativa L. salinity germination screening salt tolerance

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Damped Mathieu Equation with a Modulation Property of the Homotopy Perturbation Method

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Sound & Vibration 2022年第1期56卷 21-36页

作者： Yusry O.El-Dib nasser S.Elgazery Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

In this article,the main objective is to employ the homotopy perturbation method(HPM)as an alternative to classical perturbation methods for solving nonlinear equations having periodic *** a simple example,the nonlinear damping Mathieu equation has been *** this investigation,two nonlinear solvability conditions are *** of them was imposed in the first-order homotopy perturbation and used to study the stability behavior at resonance and non-resonance *** next level of the perturbation approaches another solvability condition and is applied to obtain the unknowns become clear in the solution for the firstorder solvability *** approach assumed here is so significant for solving many parametric nonlinear equations that arise within the engineering and nonlinear science.

关键词： Damped Mathieu Equation parametric nonlinear oscillator resonance instability homotopy perturbation method(HPM)

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CO_(2)utilization in syngas conversion to dimethyl ether and aromatics:Roles and challenges of zeolites-based catalysts

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Journal of Energy Chemistry 2023年第4期79卷 418-449页

作者： Ali A.Al-Qadri Galal A.nasser Haruna Adamu Oki Muraza Tawfik A.Saleh Department of Chemical Engineering King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Interdisciplinary Research Center for Hydrogen and Energy Storage(IRC-HES) King Fahd University of Petroleum&MineralsDhahran 31261Saudi Arabia Department of Environmental Management Technology and Department of ChemistryAbubakar Tafawa Balewa UniversityBauchiNigeria Department of Chemistry King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

Several studies have proven a strong correlation between global warming and CO_(2)***,38 billion tons of CO_(2)are approximately emitted into the *** CO_(2)via chemical conversion to clean fuels and value-added aromatics can substantially contribute to controlling the *** the thermodynamic and environmental limitations of hydrogenation of CO_(2)alone to value-added aromatics and fuels,CO_(2)utilization has currently emerged as a promising and practical approach for the production of fuels and aromatics with simultaneous utilization of both CO and CO_(2)*** such,the approach is economically ***_(2)could be converted directly to fuels by the hydrogenation process or as a part of a syngas *** ether(DME)is a clean fuel with a higher energy density,which could be used as a substituent for several fuels such as *** the same vein,value-added aromatics such as benzene,toluene,and xylene(BTX)can be produced from a similar ***,we report a review that collects the most recent studies for the conversion of CO_(2)to DME and aromatics via zeolite-based bifunctional *** highlighted the main routes for producing DME and aromatics,as well as thoroughly discussed the conducted studies on CO_(2)hydrogenation and CO_(2)-rich syngas utilized as feedstock for conversion to DME and *** CO_(2)hydrogenation mostly occurs through the methanol-mediated reaction route but is most often limited by low selectivity and catalyst deactivation,particularly in the utilization of CO_(2)alone for the reduction *** review takes an overview of the progress made so far and concluded by identifying the roles and challenges of zeolite-based catalysts for CO_(2)utilization and conversion to DME and ***,despite the incredible growth the field received in the last couple of years,however,many research challenges and opportunities associated with this process are still abou

关键词： Clean fuel DME Aromatics Bifunctional catalyst CO_(2)mitigation

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Intelligent Student Mental Health Assessment Model on Learning Management System

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Computer Systems Science & Engineering 2023年第2期44卷 1853-1868页

作者： nasser Ali Aljarallah Ashit Kumar Dutta Majed Alsanea Abdul Rahaman Wahab Sait AlMaarefa University Ad DiriyahRiyadh13713Kingdom of Saudi Arabia Department of Business Administration Majmaah UniversityAlMajmaah11952Kingdom of Saudi Arabia Department of Computer Science and Information Systems College of Applied SciencesAlMaarefa UniversityAd DiriyahRiyadh13713Kingdom of Saudi Arabia Department of Computing Arabeast CollegesRiyadh11583Kingdom of Saudi Arabia Department of Archives and Communication King Faisal UniversityAl AhsaHofuf31982Kingdom of Saudi Arabia

A learning management system(LMS)is a software or web based application,commonly utilized for planning,designing,and assessing a particular learning ***,the LMS offers a method of creating and delivering content to the instructor,monitoring students’involvement,and validating their *** mental health issues become common among studies in higher education globally,it is needed to properly determine it to improve mental *** article develops a new seven spot lady bird feature selection with opti-mal sparse autoencoder(SSLBFS-OSAE)model to assess students’mental health on *** major aim of the SSLBFS-OSAE model is to determine the proper health status of the students with respect to depression,anxiety,and stress(DAS).The SSLBFS-OSAE model involves a new SSLBFS model to elect a useful set of *** addition,OSAE model is applied for the classiﬁcation of mental health conditions and the performance can be improved by the use of cuckoo search optimization(CSO)based parameter tuning *** design of CSO algorithm for optimally tuning the SAE parameters results in enhanced classiﬁca-tion *** examining the improved classiﬁer results of the SSLBFS-OSAE model,a comprehensive results analysis is done and the obtained values highlighted the supremacy of the SSLBFS model over its recent methods interms of different measures.

关键词： Learning management system mental health assessment intelligent models machine learning feature selection performance assessment

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Optimal Resource Allocation in Fog Computing for Healthcare Applications

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Computers, Materials & Continua 2022年第6期71卷 6147-6163页

作者： Salman Khan Ibrar Ali Shah nasser Tairan Habib Shah Muhammad Faisal Nadeem Department of Computer Software Engineering University of Engineering and TechnologyMardan23200Pakistan Department of Computer Science College of Computer ScienceKing Khalid UniversityAbhaK.S.A Informatics Complex H-8Islamabad44000Pakistan

In recent years,the significant growth in the Internet of Things(IoT)technology has brought a lot of attention to information and communication *** IoT paradigms like the Internet of Vehicle Things(IoVT)and the Internet of Health Things(IoHT)create massive volumes of data every day which consume a lot of bandwidth and ***,to process such large volumes of data,the existing cloud computing platforms offer limited resources due to their distance from IoT ***,cloudcomputing systems produce intolerable latency problems for latency-sensitive real-time ***,a newparadigm called fog computingmakes use of computing nodes in the form of mobile devices,which utilize and process the real-time IoT devices data in orders of *** paper proposes workload-aware efficient resource allocation and load balancing in the fog-computing environment for the *** proposed algorithmic framework consists of the following components:task sequencing,dynamic resource allocation,and load *** consider electrocardiography(ECG)sensors for patient’s critical tasks to achieve maximum load balancing among fog nodes and to measure the performance of end-to-end delay,energy,network consumption and average *** proposed algorithm has been evaluated using the iFogSim tool,and results with the existing approach have been *** experimental results exhibit that the proposed technique achieves a 45%decrease in delay,37%reduction in energy consumption,and 25%decrease in network bandwidth consumption compared to the existing studies.

关键词： Fog computing internet of health things resource management

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Long-term complications of the transmeatal approach (Open Transcanal) in cochlear implants: A follow-up study

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Journal of Otology 2023年第1期18卷 33-37页

作者： Hesham Saleh Almofada nasser KAlmutairi Michael Steven Timms King Faisal Specialist Hospital and Research Center RiyadhSaudi Arabia Al Faisal University College of MedicineSaudi Arabia Saudi German Hospital DubaiUnited Arab Emirates

Objective: Multiple alternative approaches of cochlear implant surgery have been described, such as the suprameatal approach, transcanal approach, transmeatal approach and middle cranial fossa ***(open trnascanal) approach has not been adapted since first described in the clinical *** aimed to assess the long-term complications of the transmeatal approach in a series of 131 patients at our center between 2004 and ***: This study was a retrospective case series of all patients who underwent cochlear implants with the transmeatal(open transcanal) approach from May 2004 to December 2008 at King Faisal Specialist and Research Hospital(Riyadh, Saudi Arabia), which were conducted by the same ***: Complications were observed often with various combinations-recurrent otitis externa, posterior tympanic membrane perforation, electrode extrusion, cholesteatoma, and chronic mastoiditis. The overall long-term complication rate was 16%(21/131). The gap between the implantation and the diagnosis of a complication ranged from <1 year to 11 years. Major complications were as follows:cholesteatoma in 5(3.8%) patients, extrusion of the electrode in 5(3.8%) patients, and tympanic membrane perforation or deep retractions in 5(3.8%) patients. Minor complications were as follows: recurrent mastoiditis with/without concomitant temporary facial nerve palsy in 4(3%) patients, recurrent otitis externa infections in 7(5%) patients, and weakness of the posterior canal wall in 1 ***: The transmeatal approach posed an high rate of complications on long-term follow-up such as cholestetoma formation, extrusion of electrode or perielectrode reaction formation to tympanic membrane and external auditory canal.

关键词： Cochlear implant Transmeatal approach Open transcanal approach Surgical complication

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Determinants of overweight and obesity and preventive strategies in Pacific countries: a systematic review

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Global Health Journal 2022年第3期6卷 122-128页

作者： Tanebu Julia Tong Masoud Mohammadnezhad nasser Salem Alqahtani Ministry of Health and Medical Services Tarawa 487Kiribati Faculty of Health Studies School of Nursing and Healthcare LeadershipUniversity of BradfordBradfordWest Yorkshire BD71DPUnited Kingdom Department of Clinical Nutrition Northern Border UniversityArar 1321Saudi Arabia

Objective:This study aimed to explore more on contributing factors and prevention of overweight and obesity among Pacific ***:Using Cochrane library guideline,four electronic databases,PubMed,Embase,Scopus and CINAHL,were systematically searched from 2010 to *** strategy included key concepts,free text terms,and database-controlled vocabulary terms to identify articles on determinants and preventative strategies of overweight and obesity in the Pacific countries.A data extraction sheet was developed to extract relevant information required for analysis and theme development for this ***:A total of 22 articles were summarized and *** of overweight and obesity identified two themes:environmental related factors 13.6%(3/22)and sociocultural related factors 27.3%(6/22).The preventative strategies of overweight and obesity was categorized into behavioural change 22.7%(5/22),school-related 18.2%(4/22),and policies 50%(11/22).The quality assessment of articles showed“Good”68.2%(15/22),and“Fair”31.8%(7/22).Conclusion:This study highlighted two contributing,non-medication factors affecting overweight and obesity are both environmental and socio-cultural *** and obesity preventative strategies identified in the Pacific context considered behavioural change,knowledge enhancement,and policy *** research should aim at exploring the current preventative strategies in-depth,to appreciate the most feasible and recommended preventative approach within the Pacific society.

关键词： Determinants Preventative strategies Overweight Obesity Pacific Systematic review

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使用计算机断层扫描评估也门人口中松果体和脉络丛钙化的研究

使用计算机断层扫描评估也门人口中松果体和脉络丛钙化的研究

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作者： WDAAN RAMI nasser SALEH 吉林大学

学位级别：硕士

背景:松果体是位于间脑顶部,缰连合与后连合之间的红色小体,像松果一样的形状,是一个微小但功能强大的结构。它的颜色是红灰色,直径为5-8毫米。松果体属于内分泌或神经内分泌腺,对身体的稳态系统有重要影响,在各种身体功能中起着重要的... 详细信息

背景:松果体是位于间脑顶部,缰连合与后连合之间的红色小体,像松果一样的形状,是一个微小但功能强大的结构。它的颜色是红灰色,直径为5-8毫米。松果体属于内分泌或神经内分泌腺,对身体的稳态系统有重要影响,在各种身体功能中起着重要的作用。它负责产生褪黑素,控制包括生物钟、睡眠-觉醒周期、温度调节和免疫系统在内的各种生理过程。褪黑素还可以影响月经和生殖系统,并与肿瘤抑制有关。随着时间的推移,松果体会出现生理性钙化,但这种现象在一小部分儿童中也被观察到(8岁以下的儿童中有2%,青少年中有10%),到30岁时,大多数人的松果体均已出现钙化。脉络丛是由软脑膜及其上的血管与室管膜上皮共同构成的脉络组织,位于中枢神经系统的脑室内,是脑部另一个关键结构。在产生脑脊液中起着关键作用,每天产生约600毫升的液体。它在胎儿生长的第20周完成发育,室管膜细胞,它们覆盖在脑室上,形成了围绕脉络丛的连续层。到15岁时,大约5%的儿童和40岁的大多数成人观察到脉络丛的钙化。这些钙化通常可以在侧脑室、第三脑室、第四脑室、Luschka孔、Magendie孔和脉络膜裂中观察到。颅内钙化是指在脑组织内的血管壁上发生的钙沉积。虽然在某些区域的正常钙化通常无症状,但根据钙化的位置和程度,异常钙化的出现可能会导致临床症状的发生。生理性颅内钙化,如松果体和脉络丛钙化,更常见于老年人,通常不导致临床症状。然而,其他区域如血管或脑实质的钙化往往与一些临床症状相关,如帕金森病、痴呆、精神病和情绪障碍。随着现在医疗技术的不断发展,多种医疗技术不断出现并应用于临床,医疗工作人员可以通过如X线、计算机断层扫描(computed tomography,CT)、磁共振成像(Magnetic resonance imaging,MRI)和超声等多种手段来检测和诊断颅内钙化。其中,CT因其对钙化的识别更敏感,在颅内钙化的诊断中应用广泛。目的:本研究旨在利用CT扫描技术调查也门人群中松果体和脉络丛的钙化情况。比较也门不同年龄组和性别之间松果体和脉络丛的钙化率,找出松果体和脉络丛钙化大小的标准值,以及使用Hounsfield(HU)单位测量松果体和脉络丛钙化的密度,并探讨松果体和脉络丛钙化是否与某些疾病(如肾病、阿尔茨海默病、精神分裂症、糖尿病、睡眠障碍、心血管疾病、痴呆和高血压)的发展存在关联,研究这种生理钙化与疾病之间的关系。方法:本研究纳入了2021年7月至2021年12月期间在也门萨那市的政府医院和放射诊断中心的放射科使用飞利浦CT扫描仪进行脑部CT扫描的所有患者。共收集了300例病例并纳入研究,年龄1～90岁,分为1-10岁、11-20岁、21-30岁、31-40岁、41-50岁、51-60岁和60岁以上七个年龄段。通过Radi Ant DICOM查看器4.6.9程序对收集的入组人群数据进行松果体和脉络丛钙化的长度和宽度测量,并测量钙化的放射密度值(HU)。采用结构化问卷收集患者的现病史及既往史,问卷从患者处收集,年龄较小的患者信息从父母那里获取,问卷包括:肾脏疾病,阿尔茨海默氏症,精神分裂症,糖尿病,睡眠障碍,心血管疾病,痴呆症和高血压。并使用SPSS 21.0版本和Microsoft Excel 2013软件对数据进行分析。采用描述性统计,如频率和百分比,来描述样本特征。数据以表格、饼图和条形图的形式呈现。使用Pearson相关分析来确定松果体及脉络丛钙化与疾病之间的相关性。统计显著性的临界点设定为P<0.05。本研究共纳入样本300例,包括不同年龄组,将其分为1-10岁、11-20岁、21-30岁、31-40岁、41-50岁、51-60岁和60岁以上七个年龄段,其中分布最多的年龄组是1-10岁(21.0%)和60岁以上(20.3%)。从性别分布来看,男性161人(53.7%),女性139人(46.3%)。结果:对所有参与者的CT检查分析后发现,205名参与者(68.3%)存在松果体钙化,197名参与者(65.7%)有脉络丛钙化。对于脉络丛钙化而言,6名参与者(3.0%)出现右侧脉络膜丛钙化,13名参与者(6.6%)出现左侧脉络膜丛钙化,178名参与者(90.4%)出现双侧脉络膜丛钙化。松果体钙化发生率最高的是60岁以上年龄组,包括54名参与者(18.0%),发生率最低的是1-10岁年龄组,包括3名参与者(1.0%)。脉络丛钙化发生率最高的是60岁以上年龄组,包括57名参与者(19.0%)。发生率最低的是1-10岁年龄组,包括8名参与者(2.7%)。我们发现松果体和脉络丛钙化在老年人群中发生率最高,随着年龄的增长,生理性颅内钙化越来越普遍。松果体和脉络膜丛的钙化是一个随着年龄的增长而发生的自然过程,钙盐在组织中积累,形成坚硬的矿化结构,这一过程被认为与随着

关键词：松果体脉络丛钙化 CT

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Refraction characteristics of phononic crystals

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Acta Mechanica Sinica 2015年第4期31卷 481-493页

作者： Sia Nemat-nasser Department of Mechanical and Aerospace Engineering University of California

Some of the most interesting refraction prop- erties of phononic crystals are revealed by examining the anti-plane shear waves in doubly periodic elastic composites with unit cells containing rectangular and/or elliptical multi- inclusions. The corresponding band structure, group velocity, and energy-flux vector are calculated using a powerful mixed variational method that accurately and efficiently yields all the field quantities over multiple frequency pass-bands. The background matrix and the inclusions can be anisotropic, each having distinct elastic moduli and mass densities. Equifrequency contours and energy-flux vectors are read- ily calculated as functions of the wave-vector components. By superimposing the energy-flux vectors on equifrequency contours in the plane of the wave-vector components, and supplementing this with a three-dimensional graph of the corresponding frequency surface, a wealth of information is extracted essentially at a glance. This way it is shown that a composite with even a simple square unit cell con- taining a central circular inclusion can display negative or positive energy and phase velocity refractions, or simply performs a harmonic vibration （standing wave）, depending on the frequency and the wave-vector. Moreover, that the same composite when interfaced with a suitable homoge- neous solid can display：（1） negative refraction with negative phase velocity refraction; （2） negative refraction with pos- itive phase velocity refraction; （3） positive refraction with negative phase velocity refraction; （4） positive refraction with positive phase velocity refraction; or even （5） completereflection with no energy transmission, depending on the fre- quency, and direction and the wavelength of the plane-wave that is incident from the homogeneous solid to the interface. For elliptical and rectangular inclusion geometries, analyti- cal expressions are given for the key calculation quantities. Expressions for displacement, velocity, linear m

关键词： Doubly periodic composites - Phononiccrystals Band structure Group and energy-flux vectors

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