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American Journal of Computational Mathematics 2017年第3期7卷 208-227页

作者： Muhammad Saqib Shahid Hasnain Daoud suleiman Mashat Department of Mathematics Numerical Analysis King Abdulaziz University Jeddah Saudi Arabia

To develop an efficient numerical scheme for two-dimensional convection diffusion equation using Crank-Nicholson and ADI, time-dependent nonlinear system is discussed. These schemes are of second order accurate in apace and time solved at each time level. The procedure was combined with Iterative methods to solve non-linear systems. Efficiency and accuracy are studied in term of L2, L∞ norms confirmed by numerical results by choosing two test examples. Numerical results show that proposed alternating direction implicit scheme was very efficient and reliable for solving two dimensional nonlinear convection diffusion equation. The proposed methods can be implemented for solving non-linear problems arising in engineering and physics.

关键词： Crank-Nicholson Taylor’s Series Newton’s Iterative Method Alternating Direction Implicit (ADI)

Higher Order Implicit Scheme for Nonlinear Time-Dependent Convection-Diffusion- Reaction Equation

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American Journal of Computational Mathematics 2022年第2期12卷 232-248页

作者： Uzair Ahmed Daoud suleiman Mashat Dalal Adnan Maturi Department of Mathematics King Abdulaziz University Jeddah Saudi Arabia

A mathematical model comprising of nonlinear reaction, diffusion, and convection mechanisms seen in natural and anthropogenic processes is numerically investigated here. It is proposed that a higher order numerical scheme of finite difference method be used in conjunction with an iterative approach in order to solve the nonlinear one dimensional convection-diffusion-reaction equation. To account for the wide variety of physical characteristics and boundary conditions, an iterative approach is presented that yields a reliable and precise solution every time. We examined the accuracy and operational efficiency of two distinct finite difference approaches. The efficiency of the system is determined by comparing the estimated results to the appropriate analytical solution by adhering to established norms. Coherence and convergence were analyzed for each approach. The simulation results demonstrate the efficacy and accuracy of these methods in solving nonlinear convection- diffusion-reaction equations. Convection-diffusion-reaction equation modeling is critical for employing the offered results in heat and mass transport processes.

关键词： Finite Difference Method (FDM) Crank-Nicholson (CN) Fourth Order Implicit (FOI) Convection-Diffusion-Reaction (CDR)

Environmental Geochemistry of Igarra Marble Mining District, Southwestern Nigeria

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Journal of Environmental Protection 2019年第6期10卷 722-737页

作者： Mohammed suleiman Chaanda Ovie Izeze Igbinosa Temple Osaze Department of Earth Sciences Federal University of Petroleum Resources Effurun Nigeria

The determination of the impacts of marble mining on the environment in Igarra was carried out via the analysis of soil and water samples as geological medium. Seven soil samples, ten water samples and five rock samples were collected. The samples collected were subjected to petro-graphic and geochemical analysis. The mean concentration of metals in soil from Ekpeshi were Cd (3.254 mg/kg), Co (786.554 mg/kg), Cu (12.911 mg/kg), Ni (18.942 mg/kg), Pb (5.5 mg/kg), and Zn (28.457 mg/kg) while the concentrations of the water samples collected from streams, taps and wells were Cd (0.116 mg/kg), Co (15.225 mg/kg), Cu (0.542 mg/kg), Ni (0.276 mg/kg), Pb (0.486 mg/kg), and Zn (0.742 mg/kg). Lead (Pb) showed high concentration of (0.486 mg/kg), Ni (0.276 mg/kg) and Cd (0.116 mg/kg) as against acceptable limits of 0.01mg/l, 0.02 mg/l (NIS) and 0.07 mg/l (WHO) 0.003 mg/l respectively, while in soil it showed high concentration of Cd (3.254 mg/kg) compared to the acceptable limit of 0.8 mg/kg set by the Dutch Standard limit for soil. Lead, Nickel and Cadmium are found to be in high concentration in both surface and underground water, and this calls for treating water in the study area before it’s used as drinking water via drilling water boreholes by the mining and processing companies operating in the area as a form of corporate social responsibility. Also, the provisions in the mining act should holistically be implemented to safe life and health of the populace of the immediately surroundings.

关键词： Marble Mining Heavy Metals Portable Drinking Water Soil Value Igarra

Assessing Internal Software Quality Attributes of the Object-Oriented and Service-Oriented Software Development Paradigms: A Comparative Study

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Journal of Software Engineering and Applications 2011年第4期4卷 244-252页

作者： Yaser I. Mansour suleiman H. Mustafa 不详

Service-Oriented Architecture (SOA) is becoming the dominant approach for developing and organizing distributed enterprise-wide applications. Although the concepts of SOA have been extensively described in the literature and in-dustry, the effects of adopting SOA on software quality are still unclear. The aim of the paper is to analyze how adopt-ing SOA can affect software quality as opposed to the Object-Oriented (OO) paradigm and expose the differential implications of adopting both paradigms on software quality. The paper provides a brief introduction of the architectural differences between the Service-Oriented (SO) and OO paradigms and a description of internal software quality metrics used for the comparison. The effects and differences are exposed by providing a case study architected for both paradigms. The quantitative measure concluded in the paper showed that a software system developed using SOA approach provides higher reusability and lower coupling among software modules, but at the same time higher complexity than those of the OO approach. It was also found that some of the existing OO software quality metrics are inapplicable to SOA software systems. As a consequence, new metrics need to be developed specifically to SOA software systems.

关键词： Service-Oriented Architecture Object-Orientation Internal Software Quality Attributes Software Quality Metrics

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Multiverse Spacetime

Journal of Energy and Power Engineering 2017年第9期11卷 584-588页

作者： K_haled (Moh'dKhalaf) suleiman Alnobani Chemical Engineering Jordan University of Science and Technology Irbid 22110 Jordan

A theological train of reasoning is avoided in this paper. The properties of the equal operator presented earlier by Alnobani are given here. A view of the present time is given. As a consequence of the presence of time state, the verses are arranged in couples and every verse including in which we live is a live verse in the same context of human life. This paper interferes with and changes the procedures and philosophy of mathematics itself. Space, mass and time are parts of one whole which is called simply time. The aim of this paper is to make the knowledge of its subject public, so other researchers can contribute to it. The concept of a gate between verses is investigated.

关键词： Time space multiverse gate.

Conceptual Analysis of a Time-Dependent Double-Diffusive Flow over a Semi-Infinite Vertical Plate

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Journal of Applied Mathematics and Physics 2014年第4期2卷 11-16页

作者： Sunday Ojima Abah Umar suleiman Joseph Enemona Idoko Department of Mathematics Statistics and Computer Science Kaduna Polytechnic Kaduna Nigeria

This study is devoted to the analysis of a one-dimensional time-dependent double-diffusive flow over a semi-infinite vertical plate, under a convective surface boundary condition. Using similarity variable, the governing nonlinear partial differential equations have been transformed into a set of coupled nonlinear ordinary differential equations, which are solved numerically by using shooting method alongside with Runge-Kutta integration scheme as embedded in Maple software programme. The numerical results of the skin-friction coefficient, the Nusselt and Sherwood numbers are discussed and depicted graphically.

关键词： Time-Dependent Double-Diffusive Flow Semi-Infinite Vertical Plate

岩藻多糖修饰聚碳酸酯聚氨酯膜表面以提高血液相容性

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岩藻多糖修饰聚碳酸酯聚氨酯膜表面以提高血液相容性

作者： Gasim Sebit Ahmed suleiman 天津大学

学位级别：硕士

生物材料的血液相容性是开发该材料最值得考虑的问题,因为接触血液的表面可能导致血栓从而引起血管堵塞或器官故障。移植材料的表面接触血液后会引发一连串凝聚反应,形成血块和血栓,使材料的效率低下。因此,本研究采用将氨基化岩藻多糖(... 详细信息

生物材料的血液相容性是开发该材料最值得考虑的问题,因为接触血液的表面可能导致血栓从而引起血管堵塞或器官故障。移植材料的表面接触血液后会引发一连串凝聚反应,形成血块和血栓,使材料的效率低下。因此,本研究采用将氨基化岩藻多糖(AFU)接枝到聚多巴胺(PDA)涂层的聚碳酸酯(PCU)薄膜表面,以创造可用于临床医疗的生物植入材料。岩藻多糖是一种从海洋中提取的多糖类物质,有抗凝和抗血栓的特性,具有提高血液相容性的潜力。由于岩藻多糖的异构性,直接对其进行氨基化改性是可行的,可通过引入带有活性官能团的间隔分子(环氧氯丙烷),使改性后的产物发生氨基化反应。这种方法在简单、可靠和易于操作方面比之前文献报告中的技术更优。本文通过傅里叶红外光谱(FTIR)和X射线光电子能谱(XPS)证实了岩藻多糖的成功接枝,由于岩藻多糖具有亲水性,改性后的薄膜亲水性显著提高。利用扫描电子显微镜(SEM)和原子力显微镜(AFM)观察了改性后表面的形貌,结果表明,接枝后的PCU表面比不接枝的表面更粗糙。此外,体外血液相容性评价显示,岩藻多糖修饰的PCU表面血小板粘附和活化较低,生成的凝血酶减少。综合研究结果表明,岩藻多糖的表面改性是一种改善血液接触材料血液相容性十分可行的方法。

关键词：岩藻多糖表面修饰血液相容性氨基化

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螺旋轴流式油气混输泵气液两相混输特性研究

螺旋轴流式油气混输泵气液两相混输特性研究

作者： OSAM ISHAG suleiman IBRAHIM 兰州理工大学

学位级别：硕士

螺旋轴流两相流是工程中最常见的流型,随着海上和陆上油田的发展,随着两相流的含气量和位置的不同,螺旋轴流多相流泵已成为研究热点。具有有效的工作方式和经济效益由于复杂的结构类型不同和流动介质的特性随着螺旋轴向气液多相泵的大... 详细信息

螺旋轴流两相流是工程中最常见的流型,随着海上和陆上油田的发展,随着两相流的含气量和位置的不同,螺旋轴流多相流泵已成为研究热点。具有有效的工作方式和经济效益由于复杂的结构类型不同和流动介质的特性随着螺旋轴向气液多相泵的大规模应用,泵内复杂的气液两相流逐渐成为一个棘手的难题,在这一点上,螺旋轴流油气混合输送泵的研究不再局限于优化和提高效率和性能,而更深入的研究是对气液两相流的研究。不同GVF和转速下的斜轴多相泵的相流特性,本文研究了以下主题,本文采用单级螺旋由研究组联合研究设计的轴流油气混合泵,并利用ANSYS对研究对象进行了流体模拟研究。其中,气液两相流模型使用欧拉多相流模型,湍流模型使用SST6)-模型,我们得到了以下结果:多相泵的性能满足设计要求,对额定扬程和效率进行了分析。除大流量小流量时实验效率低外,其他工况变化不大,表明与以前的设计相比,液压设计有所改进。GVF对不同入口GVF下压缩级的压力分布和速度分布的影响,我们已经获得了对泵压力的影响,速度将从入口到出口均匀变化。从第一级叶轮到第四级叶轮,流体的压力和速度逐渐增加。不同的GVF和输入速度对压差,效率,输入功率的影响为了满足传输的需求,当泵在油田运行时,应使用某些测量仪器。当GVF较低时,压差和效率不会明显降低,但是当GVF较高时,它们会明显下降。但是,当流向终端的流量达到其限制时,它们将不会对GVF的变化产生影响。但是,随着GVF的增加,入口功率会降低。多相泵必须随时调整速度以应对变化的GVF,以满足出口压力需求。基于本文的研究,为课题组对螺旋轴流式油气混输泵的气液分离产生“气穴-气堵”现象的演变机理的研究打下基础。

关键词：螺旋轴流油气混合输送泵气液两相流动态和静态级联混合运输的特点

吸气肌训练对改善脑卒中患者呼吸功能和步行能力的疗效：系统评价与Meta分析

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吸气肌训练对改善脑卒中患者呼吸功能和步行能力的疗效：系统评价...

作者： AHMAD suleiman GHAZI YACOUB 大连医科大学

学位级别：硕士

背景:脑卒中是由于大脑相关区域的出血或梗死而突然发生的局灶性神经功能损伤。既往的研究表明,神经损伤引发的肌无力不仅见于四肢的肌肉,也见于呼吸肌,表现为患侧肋间肌、膈肌、腹肌无力,导致呼吸功能异常、呼吸模式改变,减少了肺通气... 详细信息

背景:脑卒中是由于大脑相关区域的出血或梗死而突然发生的局灶性神经功能损伤。既往的研究表明,神经损伤引发的肌无力不仅见于四肢的肌肉,也见于呼吸肌,表现为患侧肋间肌、膈肌、腹肌无力,导致呼吸功能异常、呼吸模式改变,减少了肺通气量和呼吸流量,从而增加了呼吸系统并发症的风险。目的:本文使用系统评价与meta分析,目的是收集有关吸气肌训练（inspiratory muscle training,IMT）在改善脑卒中患者呼吸功能、呼吸肌力量与步行能力方面的功效的最新信息。方法:从2010年1月至2021年12月,本文在MEDLINE、EMBASE和Web of Science数据库中进行了在线检索,给出了具有95%置信区间的平均差和风险比。此外,本文使用了Cochrane工具评估偏倚风险。研究选择和数据提取:选取11项随机对照试验（randomized controlled trials,RCTs）,测量脑卒中后患者IMT与非IMT或假IMT的效果。我们提取了有关呼吸肌肉力量、呼吸功能和步行能力的数据。结果:我们的研究纳入了11项RCTs的299名参与者。患者的年龄范围为54至68岁,样本量大小范围为12至51名参与者。脑卒中发病的时间为14天至17.90个月。11篇文献中有5篇涉及急性和亚急性期的脑卒中患者（脑卒中时间少于6个月）,6篇涉及慢性期的脑卒中患者（脑卒中时间长于6个月）。对11篇文献进行的Meta分析显示,IMT对最大吸气压力（maximum inspiratory pressure,MIP）(MD=15.42,95%CI:1.23至29.62,P=0.03)、吸气肌耐力（inspiratory muscle endurance,IME）(MD=18.04,95%CI:10.50至25.58,P<0.00001)、1秒内用力呼气量（forced expired volume in 1 second,FEV）(MD=0.24,95%CI:0.11至0.38,P=0.0005)、用力肺活量（forced vital capacity,FVC）(MD=0.28,95%CI:0.15至0.41,P<0。0001)、呼气峰值流速（peak expiratory flow,PEF）(MD=0.37,95%CI:0.06至0.68,P=0.02)和6分钟步行试验（6-minute walk test,6-MWT）(MD=40.79,95%CI:26.36至55.23,P<0.00001)具有有利影响。对收集到的数据进行亚组分析后发现,对于脑卒中时间少于6个月的患者,吸气肌训练对肺功能FEV、FVC和步行能力（6-MWT）有更好的影响。结论:对于脑卒中时间少于6个月的患者,吸气肌训练干预在改善肺功能参数（FEV、FVC、PEF）、吸气肌力量（MIP、IME）和步行能力等方面具有显著效果。

关键词：吸气肌训练脑卒中呼吸功能步行能力

Development of River Rating Curves for Simple to Complex Hydraulic Structure Based on Calibrated HEC-RAS Hydraulic Model, in Kwale, Coastal Kenya

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Journal of Water Resource and Protection 2019年第4期11卷 468-490页

作者： Calvince Wara Mike Thomas suleiman Mwakurya Jacob Katuva Rural Focus Ltd. Nairobi Kenya University of Oxford Oxford UK

Accurate and reliable river flow information is critical to planning and management for sustainable water resources utilization. Most of engineering activities related to hydrologic designs, flood, drought, reservoirs and their operations are heavily dependent on the river flow information derived from river rating curve. The rating curve for a given river section is normally developed from a set of direct stage-discharge measurements for different periods. This involves considerable labour, risk and resources, and presupposes a complex and extensive measuring survey. Extrapolating the rating curve beyond the measured range, as common in many cases, is fraught with errors and uncertainties, due to the complex hydraulic behaviour of the surface water profile in transition from section, channel, downstream and flood plain controls which are often poorly understood with direct measurements. Hydraulic modeling has recently emerged as one of the more promising methods to efficiently develop accurate rating curves for a river section with simple or complex hydraulic structures and conditions. This paper explores the use of a Hydraulic Engineering Center-River Analysis System (HEC-RAS) model to review and develop river rating curves for three hydrometric stations on two rivers in Kwale, coastal Kenya. The HEC-RAS models were set up based on topographical (cross section and longitudinal) survey data for the reaches and engineering drawings for the hydraulic structures commonly used as section controls for flow measurement. The model was calibrated under unsteady state conditions against measured stage-discharge data which were captured using a Velocity Current Meter (Valeport) and an Acoustic Doppler Current Profiler (ADCP) for both low and high flow. The rating curves were extracted from model results and the uncertainty associated with each rating curve analyzed. The results obtained by the HEC-RAS model were satisfactory and deemed acceptable for predicting discharge acr

关键词： River Rating Curve Development Hydraulic Simulation of Stage-Discharge Relationship HEC-RAS Model Calibration