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World Journal of Engineering and Technology 2016年第2期4卷 335-360页

作者： Rasheed Atif Fawad inam Department of Mechanical and Construction Engineering Faculty of Engineering and Environment Northumbria University Newcastle upon Tyne UK

Influence of topographical features on mechanical properties of monolithic epoxy samples has been studied. The topographical features studied include waviness (Wa), roughness average (Ra), root mean square value (Rq), and maximum roughness height (Rmax or Rz). The Rz of as-cast monolithic epoxy samples was 13.93 μm. By treating with velvet cloth, the Rz value significantly decreased to 2.28 μm. The Rz value of monolithic epoxy sample treated with abrasive paper 1200P was 4.85 μm which was also lower than that of as-cast monolithic epoxy samples. However, Rz values significantly increased by treating with abrasive papers 320P and 60P and became 20.32 μm and 39.32 μm, respectively. It was interesting to note that although Ra, Wa, and Rq, all increased by treating the monolithic epoxy samples with abrasive paper 1200P, however, Rz decreased by abrasive paper 1200P. A weight loss of up to 17% was observed in monolithic epoxy samples after the treatment with the abrasive papers. Both V-shaped and U-shaped notches were produced on the surfaces of the samples. The mechanical properties were significantly degraded due to surface notches mainly because of the associated stress concentration effect. The topographical features also influenced the dynamic mechanical properties and fracture mode.

关键词： Topography Fracture Toughness Monolithic Epoxy Mechanical Properties Fractography

Fractography Analysis of Monolithic Epoxy with Tailored Topography

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World Journal of Engineering and Technology 2016年第4期4卷 517-527页

作者： Rasheed Atif Fawad inam Department of Mechanical and Construction Engineering Faculty of Engineering and Environment Northumbria University Newcastle upon Tyne UK

The topographical features of fractured tensile, flexural, K1C, and impact specimens of monolithic epoxy have been studied and correlated with mechanical properties and surface features of samples before fracture. The topographical features studied include waviness (Wa), roughness average (Ra), root mean square value (Rq), and maximum roughness height (Rmax or Rz). As surface notches generate triaxial state of stress, therefore, the crack propagation is precipitated resulting in catastrophic failure. Although surfaces can be examined before fracture for any deleterious topographical elements, however, fractured surfaces can reveal finer details about the topography. It is because, as discussed in this article, surfaces with specific topography produce fracture patterns of peculiar aesthetics, and if delved deeper, they can further be used to estimate about the topography of surfaces before fracture. In addition, treating the samples with surfaces of specific topography can help improve the mechanical properties of monolithic epoxy.

关键词： Fractography Topography Monolithic Epoxy Fracture Toughness Mechanical Properties

Modeling and Simulation of Graphene Based Polymer Nanocomposites: Advances in the Last Decade

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Graphene 2016年第2期5卷 96-142页

作者： Rasheed Atif Fawad inam Department of Mechanical and Construction Engineering Faculty of Engineering and Environment Northumbria University Newcastle UK

Modeling and simulation allow methodical variation of material properties beyond the capacity of experimental methods. The polymers are one of the most commonly used matrices of choice for composites and have found applications in numerous fields. The stiff and fragile structure of monolithic polymers leads to the innate cracks to cause fracture and therefore the engineering applications of monolithic polymers, requiring robust damage tolerance and high fracture toughness, are not ubiquitous. In addition, when “many-parts” cling together to form polymers, a labyrinth of molecules results, which does not offer to electrons and phonons a smooth and continuous passageway. Therefore, the monolithic polymers are bad conductors of heat and electricity. However, it is well established that when polymers are embedded with suitable entities especially nano-fillers, such as metallic oxides, clays, carbon nanotubes, and other carbonaceous materials, their performance is propitiously improved. Among various additives, graphene has recently been employed as nano-filler to enhance mechanical, thermal, electrical, and functional properties of polymers. In this review, advances in the modeling and simulation of grapheme based polymer nanocomposites will be discussed in terms of graphene structure, topographical features, interfacial interactions, dispersion state, aspect ratio, weight fraction, and trade-off between variables and overall performance.

关键词： Graphene Polymer Nanocomposites Modeling Simulation

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Graphene 2016年第2期5卷 55-72页

作者： Rasheed Atif Fawad inam Department of Mechanical and Construction Engineering Faculty of Engineering and Environment Northumbria University Newcastle UK

Modeling and simulation allow methodical variation of material properties beyond the capacity of experimental methods. Due to the hexagonal structure of graphene, it is considered as frame-like structure. In the frame, covalent C-C bonds are taken as beams joined together with carbon atoms placed at the joints. Uniaxial beam elements, defined by their cross-sectional area, material properties, and moment of inertia represent the covalent bonds. The parameters of the beam elements are determined by establishing equivalence between structural and computational mechanics. However, the bonds connecting the carbon atoms do not have physical existence as they are a compromise between attractive and repulsive forces. Also, defects at nanoscale make graphene different from frame-like structure. In addition, the topography of graphene makes it non-linear structure and even the axial loading changes to eccentric loading. Here we show that, by using basic statics principles, disparities between graphene and frame-likes structures can be highlighted.

关键词： Modeling Graphene Frame-Like Structure Topographical Features Stress Concentration

Genome-wide association analysis for stripe rust resistance in spring wheat(Triticum aestivum L.) germplasm

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Journal of Integrative Agriculture 2020年第8期19卷 2035-2043页

作者： Sher MUHAMMAD Muhammad SAJJAD Sultan Habibullah khan Muhammad SHAHID Muhammad ZUBAIR Faisal Saeed AWAN Azeem iqbal khan Muhammad Salman MUBARAK Ayesha TAHIR Muhammad UMER Rumana KEYANI Muhammad inamAFZAL Irfan MANZOOR Javed Iqbal WATTOO Aziz-ur REHMAN Department of Bioinformatics and Biotechnology GC UniversityFaisalabad 38090Pakistan Department of Biosciences COMSATS University Islamabad(CUI)Islamabad 45550Pakistan Centre of Agricultural Biochemistry and Biotechnology(CABB) University of AgricultureFaisalabad 38000Pakistan Department of Plant Breeding and Genetics University of AgricultureFaisalabad 38000Pakistan Department of Biotechnology Faculty of Life SciencesUniversity of Central PunjabLahore 54000Pakistan Wheat Research Institute Ayub Agricultural Research Institute(AARI)Faisalabad 38950Pakistan

Stripe rust is a continuous threat to wheat crop all over the *** causes considerable yield losses in wheat crop every *** deployment of adult plant resistance(APR)genes in newly developing wheat cultivars is the most judicious strategy to combat this ***,we dissected the genetics underpinning stripe rust resistance in Pakistani wheat *** association panel of 94 spring wheat genotypes was phenotyped for two years to score the infestation of stripe rust on each accession and was scanned with 203 polymorphic *** on D’measure,linkage disequilibrium(LD)exhibited between loci distant up to 45 c ***-trait associations(MTAs)were determined using mixed linear model(MLM).Total 31 quantitative trait loci(QTLs)were observed on all 21 wheat *** QTLs were newly discovered as well as 19 QTLs and 35 previously reported Yr genes were validated in Pakistani wheat *** major QTLs were ***.2 AL and ***.3 BS(PVE,11.9%).Dissection of genes from the newly observed QTLs can provide new APR genes to improve genetic resources for APR resistance in wheat crop.

关键词： wheat Puccinia striiformis LD GWAS MTA PCoA

Staged endovascular reconstruction of complex traumatic intracranial carotid artery dissection

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Stroke & Vascular Neurology 2020年第3期5卷 308-310页

作者： Karan K Topiwala Mohammed Hussain Janhavi Modak inam Kureshi Amre Nouh Mubashir Pervez Brendan Killory Daniel Lee Neurology University of Connecticut School of MedicineFarmingtonConnecticutUSA Interventional Neuroradiology Hartford HospitalHartfordConnecticutUSA Neurosurgery Hartford HospitalHartfordConnecticutUSA Neurology Hartford HospitalHartfordConnecticutUSA

Case presenTaTion A 32-year old woman presented with traumatic facial injuries from a horseback riding *** was found to have a Glasgow Coma Score of 3T,left eyelid ptosis with a fixed-dilated pupil and a flaccid right upper *** angiogram of the head showed complex craniofacial injuries,including a transverse fracture transecting the clivus and the left petrous temporal bone,with SAH in the suprasellar *** was a bilateral engorgement of the superior ophthalmic veins,suggestive of bilateral CCF *** subtraction angiography(DSA)showed a left petrocavernous internal carotid artery dissection(ICAD).MRI of the brain demonstrated multiple embolic infarcts in the left middle cerebral artery(MCA)territory,despite therapeutic anticoagulation with heparin.

关键词： injuries dissection traumatic

Multi-Band Metamaterial Antenna for Terahertz Applications

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Computers, Materials & Continua 2023年第1期74卷 1765-1782页

作者： Adel Y.I.Ashyap M.inam M.R.Kamarudin M.H.Dahri Z.A.Shamsan K.Almuhanna F.Alorifi Faculty of Engineering Technology Universiti Tun Hussein Onn Malaysia(UTHM)Batu Pahat86400JohorMalaysia Centre for Telecommunication Research&Innovation(CETRI) Faculty of Electrical and Electronic Engineering TechnologyUniversiti Teknikal Malaysia Melaka(UTeM)Melaka76100Malaysia Department of Electronic Engineering Dawood University of Engineering and Technology74800KarachiPakistan Electrical Engineering Department College of EngineeringImam Mohammad Ibn Saud Islamic UniversityRiyadhSaudi Arabia

A multi-band metamaterial antenna is proposed to operate at the terahertz(THz)band for medical *** proposed structure is designed on a polyimide as a support layer,and its radiating elements are made of ***,the design is started with a conventional shape showing a single operating frequency at 1.1 *** achieve a multi-band operating frequency,the conventional shape was replaced with the proposed metamaterial as a radiating patch that has properties not exist in *** multi-band frequencies are obtained without compromising the overall size of the *** overall size is 600×600×25μm^(3).The operating frequencies are 0.36,0.49,0.69,0.87,and 1.04 THz.A full ground plane is used to behave as isolation between the design and the human body *** proposed design is investigated on free space and on the human body model,showing excellent performance in both *** achieved gains for the following frequencies 0.36,0.49,0.69,0.87,and 1.04 THz are 4.81,6.5,8.41,6.02,and 7.96 dB,respectively,while the efficiencies are 83.91%,96.28%,90.80%,91.71%,and 92.99%,*** conventional design was modified to have a partial ground to show the benefit of using the full *** design is loaded on the human body model and its performance is *** efficiency and gain are 6.61 dB and 95.58.7%for the case of no human body model,and 4.26 dB and 40.30%for the case of using a human body ***,the proposed metamaterial antenna will be useful for future medical applications in the THz band.

关键词： THz 5G a multi-band metamaterials 6G WBAN

Design of Secure and Traceable Requirement Engineering Process for Security-Sensitive Projects

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Journal of Software Engineering and Applications 2017年第12期10卷 873-883页

作者： Abdul Ahad Luqman Tariq Saba Niaz Muhammad inam Department of Computer Science Virtual University Lahore Pakistan Department of Computer Science Preston University Islamabad Pakistan Department of Computer Science Beijing University of Technology Beijing China

With continuous evolution in software industry, security is becoming very important in software projects. However, in many development methodologies, security is thought to be added in the project at later stages of the development lifecycle. There are also many proposed methodologies where the security measures are considered at requirement engineering stage of the development lifecycle, but many of them still do not seem adequate for applicability due to the reason that these approaches do not provide sufficient support for mapping the security requirements to the later stages of development. So, we are in need of a software requirement engineering approach, which is not only helpful in security requirement specification at requirement engineering stage but also provides support for using the specified security requirements at later stages of development. To meet this requirement, we introduce a new method Secure and Traceable Requirement Engineering Process (STREP). This method also helps the non-security-expert requirement engineers to specify requirements in such a way that the specified requirements can be used to derive security related test cases. STREP method not only deals with security issues of the system at requirement engineering stage, but also makes the security requirements more traceable to be used at later stages of development lifecycle, and as a result, secure systems are produced that are also usable as the customer wishes.

关键词： Traceable Usable Security Requirements Requirement Specification Development Lifecycle SRE Method

Periodic surface functional group density on graphene via laserinduced substrate patterning at Si/SiO2 interface

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Nano Research 2020年第9期13卷 2332-2339页

作者： Karolina A.Drogowska-Horna inam Mirza Alvaro Rodriguez Petr Kovaricek Juraj Sladek Thibault J.-Y.Derrien Mindaugas Gedvilas Gediminas Raciukaitis Otakar Frank Nadezhda M.Bulgakova Martin Kalbac J.Heyrovsky Institute of Physical Chemistry of the Czech Academy of Sciences Dolejskova 2155/318223 PragueCzech Republic HiLASE Centre Institute of Physics of the Czech Academy of SciencesZa Radnict 82825241 Dolni BrezanyCzech Republic Faculty of Nuclear Sciences and Physical Engineering Czech Technical University in PragueBrehova 78/711519Czech Republic Center for Physical Sciences and Technology Savanoriu Ave.231LT-023000VilniusLithuania

Controlling the spatial distribution of functional groups on two-dimensional(2D)materials on a micrometer scale and below represents a fascinating opportunity to achieve anisotropic(opto)electronic properties of these *** patterns of covalent functionalization can lead to pericxJic potentials in the monolayer;however,creating such superstructures is very ***,we describe an original approach to the periodic functionalization of graphene induced by substrate patterning using a pulsed ***-induced periodic surface structures(LIPSS)are produced on silicon wafers with thermally-grown oxide *** irradiation conditions for the formation of UPSS confined at the SiO2/Si interface have been *** imprint their periodicity to the reactivity of the monolayer graphene placed on the substrate via modulation of its local doping *** method is clean,straightforward and scalable with high spatial resolution.

关键词： two-dimensional(2D)materials graphene functionalization laser-induced periodic surface structures(LIPSS) periodic patterns Raman spectroscopy atomic force microscopy(AFM)

Missed Prevention of Mother-to-Child Transmission of HIV (PMTCT) Visits and Associated Programmatic Predictors: A Pilot Study

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Advances in Infectious Diseases 2017年第4期7卷 107-117页

作者： Augustine Ndaimani inam Chitsike Clara Haruzivishe Babill Stray-Pedersen Department of Nursing Science University of Zimbabwe College of Health Sciences Harare Zimbabwe Department of Paediatrics University of Zimbabwe College of Health Sciences Harare Zimbabwe Division of Women Rikshospitalet Institute of Clinical Medicine University of Oslo Oslo Norway

Missed Prevention of Mother-to-Child Transmission of HIV (PMTCT) visits have contributed to the delayed achievement of elimination of mother-to-child transmission of HIV. Missed visits promote attrition from prevention of mother-to-child transmission of HIV program and antiretroviral drug resistance. The purpose of the study was to determine the prevalence of missed PMTCT visits and its associated predictors. A descriptive cross sectional survey was carried out at a District Hospital in Goromonzi, Zimbabwe. Fifty-three women completed closed-ended questionnaires pertaining to PMTCT visits and exposure to PMTCT activities. A total of 24.5% missed at least one scheduled PMTCT visit. Statistically significant predictors of not missing a PMTCT visit were satisfaction with family support (β = −0.73, p = 0.029) and level of satisfaction with PMTCT services (β = −0.00076;p = 0.04). The number of days by which scheduled visits were missed were inversely correlated with visit number (β = −2.99, p = 0.04). Enhanced family support and quality improvement to improve patient satisfaction may reduce missed visits. Availing women with a more active role in PMTCT may also reduce the prevalence of missed visits.

关键词： Missed Visits Option B Plus Pilot Study PMTCT (Prevention of Mother-to-Child Transmission of HIV) Predictors