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Journal of Green Building 2017年第2期12卷 112-129页

作者： omar S.Asfour Faculty of Engineering Dept.of ArchitectureIslamic University of GazaP.O.Box 108Gaza CityPalestine

This study aims to examine the effect of building plan form on internal thermal comfort conditions in naturally ventilated open-plan buildings located in hot *** study examined the square and the rectangular plan forms in relation to several values of wind direction,building plan depth,and climatic *** study utilised CFD for ventilation prediction,DesignBuilder for thermal modelling,and the Tropical Summer Index(TSI)for thermal comfort *** three tools were integrated in a quantitative approach to fulfil the study *** study concluded that the use of area-weighted average velocity magnitude is more accurate in the assessment of natural ventilation performance,as it accounts for both internal velocity magnitude and *** study confirmed the common observation that the use of shallow building plans is more effective to increase internal air velocity and improve internal thermal *** some point of increased plan depth,the internal air velocity magnitude dramatically *** the three examined wind directions,this occurred when the plan depth exceeded 3H in the square cases and 2.5H in the rectangular ones,where H is the building *** value is much less than the commonly recommended maximum value of *** study also concluded that reducing building depth in the square cases has generally more potential to improve thermal comfort conditions when compared with the rectangular *** gross increase in Percentage of People Comfortable,PPC,in all the examined cases was 23%in the square cases,compared to 11%in the rectangular cases.

关键词： natural ventilation buildings open-plan thermal comfort hot climate

Low-Cost IMU Sensors for Satellite Maturity Improvement

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Computer Systems Science & Engineering 2022年第12期43卷 1315-1326页

作者： omar Ben Bahri Abdullah Alhumaidi Alotaibi Department of Science and Technology College of RanyahTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

The satellite technology proves its impact in the modern era with itswide benefits and applications. However, the cost of the development in this fieldpresents gaps in many countries, almost the developed countries. Therefore, thispaper provides a rich platform around low-cost sensors in order to improve maturity in space technology, mostly the system of attitude determination and *** development of this knowledge turns out to be very interesting in order toachieve a space mission which leads to the progression of the spatial technologyreadiness level (TRL) defined by the international measurement scale which isable to estimate the technological maturity. Thus, the idea is carried out for thedevelopment of low-cost sensors’ system for attitude determination around anArduino board. A sensor fusion method was applied on three types of sensors:accelerometer, magnetometer, and gyroscope in order to detect the reliable orientation. It is aimed to apply quaternion based Kalman filter on different platformthan previous systems. It is succeeded therefore to improve measurementaccuracy around low-cost sensor to achieve the main goal of this paper.

关键词： ADS IMU sensors kalman filter low-cost satellite

Genotype-based precision nutrition strategies for the prediction and clinical management of type 2 diabetes mellitus

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World Journal of Diabetes 2024年第2期15卷 142-153页

作者： omar Ramos-Lopez Medicine and Psychology School Autonomous University of Baja CaliforniaTijuana 22390Baja CaliforniaMexico

Globally,type 2 diabetes mellitus(T2DM)is one of the most common metabolic disorders.T2DM physiopathology is influenced by complex interrelationships between genetic,metabolic and lifestyle factors(including diet),which differ between populations and geographic *** fact,excessive consumptions of high fat/high sugar foods generally increase the risk of developing T2DM,whereas habitual intakes of plant-based healthy diets usually exert a protective ***,genomic studies have allowed the characterization of sequence DNA variants across the human genome,some of which may affect gene expression and protein functions relevant for glucose *** comprehensive literature review covers the impact of gene-diet interactions on T2DM susceptibility and disease progression,some of which have demonstrated a value as biomarkers of personal responses to certain nutritional ***,novel genotype-based dietary strategies have been developed for improving T2DM control in comparison to general lifestyle ***,progresses in other omics areas(epigenomics,metagenomics,proteomics,and metabolomics)are improving current understanding of genetic insights in T2DM clinical *** more investigation is still needed,the analysis of the genetic make-up may help to decipher new paradigms in the pathophysiology of T2DM as well as offer further opportunities to personalize the screening,prevention,diagnosis,management,and prognosis of T2DM through precision nutrition.

关键词： Type 2 diabetes mellitus Nutrigenetics Single nucleotide polymorphism Genotype Diet Precision nutrition

Simple operated multipurpose temperature control cryostat

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 793-796页

作者： ABBAS T.A. omar M.S. Department of Physics College of Science University of SalahaddinArbilIraqi KurdistanIraq

A suitable simple optical cryostat for optical, magneto-optical, electrical and thermo-electrical measurements was designed. It is suitable for use in a magnetic pool gap as narrow as less than 1 cm. Throughout a long period of time, the heat diffusion process of the cryostat can be easily operated at slow increase in sample temperature in a range 1.25 K/min at 200 K that will be reduced gradually to 0.66 K at room temperature. Liquid nitrogen was used to cool down the temperature. During the operation, the change in the measured energy gap of a semiconductor sample and other physical parameters resulting from the change of temperature can be corrected through the temperature coefficient of that parameter at the corresponding temperature. The cryostat was successfully used for all experiments mentioned above to measure the properties of a single crystal of GaP (Gallium Phosphate) semiconductor.

关键词： Optical cryostat Electrical cryostat Magneto-optical cryostat

Production of renewable fuels by blending bio-oil with alcohols and upgrading under supercritical conditions

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Frontiers of Chemical Science and Engineering 2019年第4期13卷 702-717页

作者： Sainab omar Suzanne Alsamaq Yang Yang Jiawei Wang Chemical Engineering and Applied Chemistry Aston UniversityBirmingham.B47ETUK European Biocncrgy Research Institute Aston UniversityBirminghamB47ETUK

The work studied a non-catalytic upgrading of fast pyrolysis bio-oil by blending under supercritical conditions using methanol,ethanol and isopropanol as solvent and hydrogen *** of the bio-oil and the upgraded bio-oils was carried out including moisture content,elemental content,pH,heating value,gas chromatography-mass spectrometry(GCMS),Fourier transform infrared radiation,13C nuclear magnetic resonance spectroscopy,and thermogravimetric analysis to evaluate the effects of blending and supercritical *** GCMS analysis indicated that the supercritical methanol reaction removed the acids in the bio-oil consequently the pH increased from 2.39 in the crude bio-oil to 4.04 after the supercritical methanol *** ester contents increased by 87.49% after the supercritical methanol reaction indicating ester formation could be the major deacidification mechanism for reducing the acidity of the bio-oil and improving its pH *** blending crude bio-oil with isopropanol was effective in increasing the C and H content,reducing the O content and increasing the heating value to 27.55 from 17.51 MJ·kg^-1 in the crude *** the supercritical isopropanol reaction,the heating value o f the liquid product slightly further increased to 28.85 MJ·kg^-1.

关键词： bio-oil blending supercritical upgrading characterisation

Nickel-titanium shape memory alloys made by selective laser melting:a review on process optimisation

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Advances in Manufacturing 2022年第1期10卷 24-58页

作者： omar Ahmed Mohamed Syed Hasan Masood Wei Xu School of Engineering Deakin UniversityGeelongVIC 3216Australia Department of Mechanical Engineering The Higher Institute of Engineering TechnologyBani WaledLibya Department of Mechanical and Product Design Engineering Swinburne University of TechnologyHawthornVIC 3122Australia

Selective laser melting(SLM)is a mainstream powder-bed fusion additive manufacturing(AM)process that creates a three-dimensional(3D)object using a high power laser to fuse fine particles of various metallic powders such as copper,tool steel,cobalt chrome,titanium,tungsten,aluminium and stainless *** the past decade,SLM has received significant attention due to its capability in producing dense parts with superior mechanical *** a premier shape memory alloy,the nickel-titanium(NiTi)shape memory alloy is attractive for a variety of biomedical applications due to its superior mechanical properties,superelasticity,corrosion resistance and *** paper presents a comprehensive review of the recent progress in NiTi alloys produced by the SLM process,with a particular focus on the relationship between processing parameters,resultant microstructures and *** research gaps,challenges and suggestions for future research are also addressed.

关键词： Additive manufacturing(AM) Selective laser melting(SLM) Microstructure NiTi alloy Mechanical properties

Modeling, analysis, and optimization of dimensional accuracy of FDM-fabricated parts using definitive screening design and deep learning feedforward artificial neural network

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Advances in Manufacturing 2021年第1期9卷 115-129页

作者： omar Ahmed Mohamed Syed Hasan Masood Jahar Lal Bhowmik School of Engineering Deakin UniversityGeelongAustralia Department of Mechanical Engineering Higher Institute of Engineering TechnologyBani WalidLibya Department of Mechanical and Product Design Engineering Swinburne University of TechnologyHawthornVIC 3122Australia Department of Health Science and Biostatistics Swinburne University of TechnologyHawthornVIC 3122Australia

Additive manufacturing(AM)technologies such as fused deposition modeling(FDM)rely on the quality of manufactured products and the process ***,the dimensional accuracy and stability of any AM process is essential for ensuring that customer specifications are satisfied at the highest standard,and variations are controlled without significantly affecting the functioning of processes,machines,and product *** study aims to investigate the effects of FDM fabrication conditions on the dimensional accuracy of cylindrical *** this study,a new class of experimental design techniques for integrated second-order definitive screening design(DSD)and an artificial neural network(ANN)are proposed for designing experiments to evaluate and predict the effects of six important operating *** determining the optimum fabrication conditions to obtain better dimensional accuracies for cylindrical parts,the time consumption and number of complex experiments are reduced considerably in this *** optimum fabrication conditions generated through a second-order DSD are verified with experimental *** results indicate that the slice thickness,part print direction,and number of perimeters significantly affect the percentage of length difference,whereas the percentage of diameter difference is significantly affected by the raster-to-raster air gap,bead width,number of perimeters,and part print ***,the results demonstrate that a second-order DSD integrated with an ANN is a more attractive and promising methodology for AM applications.

关键词： Artificial neural network(ANN) OptimizationDefinitive screening design(DSD) Analysis of variance(ANOVA) Fused deposition modeling(FDM) Dimensional accuracy

Performance of Desiccant-Based Cooling Systems in Hot-Humid Climates: A Review

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Energy Engineering 2021年第4期118卷 875-909页

作者： Maatouk Khoukhi omar Al Khatib Architectural Engineering Department College of EngineeringUnited Arab Emirates UniversityAl AinUnited Arab Emirates

This paper reviews the principle and application of the thermally activated desiccant cooling systems with their capability to perform efficiently in hot-humid *** paper first introduces the continuous increase of thermal comfort required in building and their relation with the consumption of conventional energy *** importance of desiccant cooling technology and its applications has been introduced as *** energy and environmental issues with the conventional energy supply and the demand with the environmental problems and conditions mainly related to indoor air quality have been also discussed in the second chapter of this *** third part of this paper deals with different techniques and systems applied for cooling and dehumidification including the principles of solid and liquid desiccant ***,these systems perform well in hothumid *** result of a case study of the solid desiccant cooling system combined with solar energy for the desiccant wheel regeneration has been presented in the last chapter in this paper to show the capability of these systems once well applied in a hot-humid climate.

关键词： Desiccant cooling energy performance thermal comfort environmental condition solar energy

A novel controllable crowbar based on fault type protection technique for DFIG wind energy conversion system using adaptive neuro-fuzzy inference system

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Protection and Control of Modern Power Systems 2018年第1期3卷 337-348页

作者： omar Noureldeen I.Hamdan Department of Electrical Engineering Faculty of EngineeringSouth Valley UniversityQena 83523Egypt

This paper proposes a novel controllable crowbar based on fault type(CBFT)protection technique for doubly fed induction generator(DFIG)wind energy conversion system connected to *** studied system consists of six DFIG wind turbines with a capacity of 1.5 MW for each of *** operation mechanism of proposed technique is used to connect a set of crowbar resistors in different connection ways via activation of controllable circuit breakers(CBs)depending on the detected fault *** each phase of DFIG,a crowbar resistor is connected in parallel with a controllable CB and all of them are connected in series to grid *** adaptive neuro-fuzzy inference system(ANFIS)networks are designed to detect the fault occurrence,classify the fault type,activate the CBs for crowbar resistors associated with faulted phases during fault period,and deactivate them after fault *** effectiveness of proposed CBFT protection technique is investigated for different fault types such as symmetrical and unsymmetrical faults taking into account the single-phase to ground fault is the most frequently fault type that occurs in power ***,a comparison between the behaviours of studied system in cases of using traditional parallel rotor crowbar,classical outer crowbar,and proposed CBFT protection techniques is *** fluctuations of DC-link voltage,active power,and reactive power for studied system equipped with different protection techniques are ***,the impacts of different crowbar resistance values on the accuracy of proposed technique are *** simulation results show that,the proposed technique enhances the stability of studied wind turbine generators and contributes in protection of their components during faults.

关键词： ANFIS networks Crowbar Power electronic converters DFIG wind turbines Fault types

Design of robust intelligent protection technique for large-scale grid-connected wind farm

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Protection and Control of Modern Power Systems 2018年第1期3卷 179-191页

作者： omar Noureldeen I.Hamdan Electrical Engineering Department Faculty of EngineeringSouth Valley UniversityQena 83523Egypt

This paper presents a design of robust intelligent protection technique using adaptive neuro-fuzzy inference system(ANFIS)approach to detect and classify the fault types during various faults occurrence in large-scale grid-connected wind ***,it is designed to determine the fault location and isolate the wind turbine generators located in the faulted zone during fault occurrence and reconnect them after fault *** studied wind farm has a total rating capacity of 120 MW,where it consists of 60 doubly fed induction generator(DFIG)wind turbines each has a capacity of 2 ***,the wind farm generators are positioned in 6 rows,where each row consists of 10 *** impacts of fault type,fault location,fault duration,cascaded faults,permanent fault and external grid fault on the behaviours of the generated active and reactive power are ***,the impacts of internal and external faults in cases of different transition resistances are *** simulation results indicate that,the proposed ANFIS protection technique has the ability to detect,classify and determine the fault location,then isolate the faulted zones during fault occurrence and reconnect them after fault ***,the wind turbines generators which are located in un-faulted zones can stay to deliver their generated active power to the grid during fault period.

关键词： ANFIS Fault location DFIG Wind farm Active power Reactive power