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defence Technology（防务技术） 2020年第6期16卷 1098-1105页

作者： suhad d.salman Mechanical Engineering department College of EngineeringMustansiriyah UniversityBaghdadIraq

due to notable characteristics,sustainability concept and environmental issues,hybridisation natural with synthetic fibres to fabricate composites have been rapidly gaining market share in different applications(structural,military,aerospace and automotive vehicles).Compression,tension and fatigue tests of various stacking sequences of plain jute/carbon reinforced(PVB)polyvinyl butyral by hot hydraulic press technique were experimentally *** types of fabricated composites with various constituents(jute,carbon and their hybrids)were fabricated and ***,fatigue lifetime of hybrids increases with increasing the carbon content relative to the jute fibre *** the other hand,Jute composites possess high strain compared to pure carbon composite,which gives an overall improvement in mechanical ***,H1 hybrid with Carbon/Jute/Carbon sequences offers similar fatigue stiffness behaviour of H3 hybrid with Carbon/Jute/Carbon/Jute sequences when subjected to cyclic *** composite(C)exhibited the highest fatigue resistance,whiles jute composite(J)possessed the highest strain and semi brittle trends in both mechanical and fatigue *** concluded that plain jute fibres could partially replace high-cost synthetic carbon fibres to produce more eco-friendly hybrids to be utilised in different composites industries.

关键词： Plain woven jute Carbon fabric Hybrid composite Mechanical Cyclic loading Morphological Fatigue properties

Flutter analysis of hybrid metal-composite low aspect ratio trapezoidal wings in supersonic flow

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Chinese Journal of Aeronautics 2017年第1期30卷 196-203页

作者： Shokrollahi Saeed Shafaghat salman department of Aerospace Engineering Malek Ashtar University of Technology

An effective 3d supersonic Mach box approach in combination with non-classical hybrid metal-composite plate theory has been used to investigate flutter boundaries of trapezoidal low aspect ratio wings. The wing structure is composed of two main components including aluminum material（in-board section） and laminated composite material（out-board section）. A global Ritz method is used with simple polynomials being employed as the trial functions. The most important objective of the present research is to study the effect of composite to metal proportion of hybrid wing structure on flutter boundaries in low supersonic regime. In addition, the effect of some important geometrical parameters such as sweep angle, taper ratio and aspect ratio on flutter boundaries were studied. The results obtained by present approach for special cases like pure metallic wings and results for high supersonic regime based on piston theory show a good agreement with those obtained by other investigators.

关键词： Assumed mode method Flutter Hybrid trapezoidal plateMach box method Supersonic flow

Bifurcation and Stability Analysis of the Hamiltonian-Casimir Model of Liquid Sloshing

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Chinese Physics Letters 2012年第6期29卷 46-49页

作者： salman Ahmad YUE Bao-Zeng department of Humanities&Sciences Institute of Space TechnologyIslamabad 44000Pakistan department of Mechanics School of Aerospace EngineeringBeijing Institute of TechnologyBeijing 100081

Motion stability of a spacecraft is discussed.A canonical Hamiltonian model for liquid sloshing is presented for a moving rigid *** equivalent mechanical pendulum model is used to represent the fuel slosh inside the *** this model sloshing is represented by the moving mass,the rest of the mass of the spacecraft is assumed to be *** spacecraft structure is considered to be an elliptical rigid shape and the steady rotation along the x-axis is taken as the major-axis *** stability for the present model is analyzed using the Lyapunov theory with Casimir energy *** for stability and instability are derived for a steady principal axis rotation of the rigid *** results are presented to distribute the region into stable and unstable *** this,the nonlinear behavior of the system is analyzed under the influence of an external force acting *** is observed through a bifurcation *** time history map and phase portrait are also presented to analyze the nonlinear behavior of the system.

关键词： Hamiltonian rotation stability

design of a P-&-O algorithm based MPPT charge controller for a stand-alone 200W PV system

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Protection and Control of Modern Power Systems 2018年第1期3卷 268-275页

作者： salman salman Xin AI Zhouyang WU State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

Solar cells convert sun light into electricity,but have the major drawbacks of high initial cost,low photo-conversion efficiency and *** current-voltage characteristics of the solar cells depend on solar insolation level and temperature,which lead to the variation of the maximum power point(MPP).Herein,to improve photovoltaic(PV)system efficiency,and increase the lifetime of the battery,a microcontroller-based battery charge controller with maximum power point tracker(MPPT)is designed for harvesting the maximum power available from the PV system under given insolation and temperature *** different MPPT techniques,perturb and observe(P&O)technique gives excellent results and thus is *** work involves the design of MPPT charge controller using dC/dC buck converter and microcontroller.A prototype MPPT charge controller is tested with a 200 W PV panel and lead acid *** results show that the designed MPPT controller improves the efficiency of the PV panel when compared to conventional charge controllers.

关键词： PV system Maximum power point tracker(MPPT) Perturb and observe(P&O)technique Charge controller Microcontroller

Impact of slip boundary on sloshing motions in partially filled containers

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Chinese Science Bulletin 2011年第25期56卷 2674-2678页

作者： AHMAd.salman department of Mechanics School of Aerospace Engineering Beijing Institute of Technology

Sloshing is a kind of fluid motion inside partially filled containers. In spacecraft and other partially filled moving containers, sloshing plays an important role. The contact line between the fluid and solid boundary affects the fluid movement and sloshing during motion. A physical model for steady fluid flow with a partial slip boundary is presented and equations for this model are derived for cylindrical (tube-shaped) tanks. This gives a nonlinear system of differential equations that is solved numerically by using a Successive Over-Relaxation (SOR) technique and graphical results are shown. Variations in steady fluid flow are observed with changes in the slip length and some useful results are derived. The effects on the microscopic radius of the fluid layer in a capillary tube are also shown through graphical results.

关键词：部分填充晃动滑移容器流体运动物理模型流体流动图形显示

Significance of including lid thickness and particle shape factor in numerical modeling for prediction of particle trap efficiency of invert trap

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Water Science and Engineering 2024年第2期17卷 166-176页

作者： salman Beg deo Raj Kaushal department of Civil Engineering Indian Institute of Technology DelhiNew Delhi 110016India

Sediment accumulation on the bed of open sewers and drains reduces hydraulic efficiency and can cause localized *** invert traps installed underneath the bed of open sewers and drains can eliminate sediment build-up by catching sediment *** three-dimensional(3d)computational studies have examined the particle trapping performance of invert traps of different shapes and depths under varied sediment and flow conditions,considering particles as *** two-dimensional and 3d numerical modeling,researchers assumed the lid geometry to be a thin line and a plane,*** this 3d numerical study,the particle trapping efficiency of a slotted irregular hexagonal invert trap fitted at the flume bottom was examined by incorporating the particle shape factor of non-spherical sewage solid particles and the thicknesses of upstream and downstream lids over the trap in the discrete phase model of the ANSYS Fluent 2020 R1 *** volume of fluid(VOF)and the realizable k-turbulence models were used to predict the velocity *** two-dimensional particle image velocimetry(PIV)was used to measure the velocity field inside the invert *** results showed that the thicknesses of upstream and downstream lids affected the velocity field and turbulent kinetic energy at all flow *** joint impact of the particle shape factor and lid thickness on the trap efficiency was *** both the lid thickness and particle shape factor were considered in the numerical modeling,trap efficiencies were underestimated,with relative errors of-8.66%to-0.65%in comparison to the experimental values of Mohsin and Kaushal(2017).They were also lower than the values predicted by Mohsin and Kaushal(2017),which showed an overall overestimation with errors of-2.3%to 17.4%.

关键词： Invert trap Lid thickness Particle image velocimetry Particle shape factor Turbulent kinetic energy Scanning electron microscope

Computational investigation of powder coating of nanoparticles in supersonic and hypersonic impactors

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Particuology 2013年第3期11卷 273-281页

作者： Nima Niksefat Mousa Farhadi Kurosh Sedighi salman Nourouzi Faculty of Mechanical Engineering Babol University of Technology

In this study, numerical simulation of flow field in a supersonic/hypersonic impactor with one or two nozzles was carried out using a commercial computational fluid dynamics （CFd） software FLUENT. The objective was to investigate the effects of working parameters such as pressure ratio （50 〈 Po]Pb 〈 800）, nozzle diameters （d=0.23, 0.27, 0.45 mm）, nozzle to plate distance （0.5 〈L/d〈 50）, particle diameter （1 nm〈 dp 〈 100 nm ） and angle between two nozzles. A single-phase 3d unsteady-state model was implemented by the software. For this purpose, a user-defined function （UdF） was employed to implement nanoparticles for different assumptions of Cunningham correction factor. An axisymmetric form of the compressible Navier-Stokes and energy equations was used for both fluid flow and temperature; Lagrangian particle trajectory analysis was used for particle motion. Using the variable Cunningham cor- rection factor showed suitable agreement with experimental data in comparison with other methods. Results show that increase of the distance between nozzle and impaction plate causes increase of Mach number, the distance between bow shock and impaction plate, and the collection efficiency. Maximum jet velocity, distance between bow shock and impaction plate and collection efficiency increase by using two nozzles in supersonic and hypersonic imoactors.

关键词： Impactor Supersonic and hypersonic flow Nanoparticles Aerosol Aerodynamics

Resolvability in Circulant Graphs

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Acta Mathematica Sinica,English Series 2012年第9期28卷 1851-1864页

作者： Muhammad.salman Imran JAVAId Muhammad Anwar CHAUdHRY Center for Advanced Studies in Pure and Applied Mathematics Bahauddin Zakariya University

A set W of the vertices of a connected graph G is called a resolving set for G if for every two distinct vertices u, v E V（G） there is a vertex w E W such that d（u, w） ≠ d（v, w）. A resolving set of minimum cardinality is called a metric basis for G and the number of vertices in a metric basis is called the metric dimension of G, denoted by dim（G）. For a vertex u of G and a subset S of V（G）, the distance between u and S is the number minses d（u,s）. A k-partition II = {$1,$2,..., Sk} of V（G） is called a resolving partition if for every two distinct vertices u, v E V（G） there is a set Si in H such that d（u, Si） ≠ d（v, Si）. The minimum k for which there is a resolving k-partition of V（G） is called the partition dimension of G, denoted by pd（G）. The circulant graph is a graph with vertex set Zn, an additive group of integers modulo n, and two vertices labeled i and j adjacent if and only if i - j （rood n） E C, where C C Zn has the property that C = -C and 0 ￠ C. The circulant graph is denoted by Xn,△ where A = ｜C｜. In this paper, we study the metric dimension of a family of circulant graphs Xn,3 with connection set C = {1, 3, n - 1} and prove that dim（Xn,3） is independent of choice of n by showing that dim（Xn,a） = {3 for all n ≡0 （mod 4）,4 for all n≡2 （mod4）.We also study the partition dimension of a family of circulant graphs Xm,4 with connection set C = {±1, ±2} and prove that pd（Xn,4） is independent of choice of n and show that pd（X5,4） = 5 and pd（Xn,a） ={ 3 for all odd n≥9,4 for all even n≥6 and n=7.

关键词： Circulant graphs metric dimension partition dimension

A Simple Human Vulnerability Index to Climate Change Hazards for Pakistan

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International Journal of disaster Risk Science 2012年第3期3卷 163-176页

作者： Fazal Ali Khan Ali salman Social Science and Economics department Shaheed Zulfikar Ali Bhutto Institute of Science and Technology(SZABIST)Islamabad 44000Pakistan Rural Support Programmes Network(RSPN) Islamabad 44000Pakistan development Pool Islamabad 44000Pakistan

This article explores the spatial pattern of vulnerability to climate change hazards in Pakistan by developing a Human Vulnerability Index(HVI). For this purpose, we use Population Census 1998 and Agriculture Census 2000 data. The HVI places the 103 districts of Pakistan in rank order and looks at whether there is a correlation between human vulnerability and exposure to disaster of the districts with respect to climate change hazards such as floods. The HVI is further validated using an independent flood recovery data set. The study found that the HVI is a useful tool for identifying vulnerable regions and districts for resource allocation. But the HVI is a poor tool for vulnerability assessment at community and household levels. For this purpose we used logistic regression analysis, which indicates that the adult literacy rate, ownership of livestock, and access to electricity are the three(out of six) key variables that play a critical positive role in recovery after the 2010 floods. The primary data collected from households also reveal that the 2010 Pakistan floods have equally affecte d standing crops, livestock, and house structures. More than two-thirds of sample households had rebuilt their house structures, whereas livestock recovery was negligible since the floods. We also found that the 2010 floods affected some of the poverty regions of the country, but that there is a very weak systematic correlation between human vulnerability and disaster exposure.

关键词： floods disaster district

Surgical outcome of laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass for resolution of type 2 diabetes mellitus:A systematic review and meta-analysis

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World Journal of Gastroenterology 2020年第8期26卷 865-876页

作者： salman Yousuf Guraya Tim Strate Clinical Sciences department College of MedicineUniversity of SharjahSharjah 27272United Arab Emirates department of Surgery Reinbek HospitalAcademic Teaching Hospital of the University of HamburgReinbek D-21465Germany

BACKGROUNd Bariatric procedures are considered superior to medical therapies in managing type 2 diabetes mellitus(T2dM).Laparoscopic Roux-en-Y gastric bypass(LRYGB)and laparoscopic sleeve gastrectomy(LSG)are the most commonly used procedures for weight loss and comorbidity resolution ***,it is not yet known whether the degree of T2dM is influenced by the choice of bariatric *** To quantitatively compare T2dM resolution over 1-5 years follow-up by LRYGB and LSG in morbidly obese *** We searched the selected databases for full-text English language clinical studies that compared the effectiveness of LRYGB and LSG for T2dM *** manager 5.3 was used for data analysis,and the overall effect summary was represented in a forest *** From 1,650 titles retrieved by an initial search,we selected nine studies for this *** found insignificant differences for T2dM resolution by LRYGB and LSG,with an odds ratio of 0.93(95%CI:0.64-1.35,Z statistics=0.38,P=0.71).Additionally,subset analyses for T2dM resolution showed insignificant differences after 24 mo(χ^2=1.24,df=4,P=0.87,overall Z effect=0.23),36 mo(χ^2=0.41,df=2,P=0.81,overall Z effect=0.51),and 60 mo(χ^2=4.75,df=3,P=0.19,overall Z effect=1.20)by LRYGB and *** study reports a T2dM remission rate of 82.3%by LRYGB and 80.7%by *** This study reports similar T2dM resolution rates by both LRYGB and LSG during 1-5 years of ***,long-term follow-up of 10 years is needed to further substantiate these findings.

关键词： Morbid obesity Type 2 diabetes mellitus Laparoscopic sleeve gastrectomy Laparoscopic Roux-en-Y gastric bypass