检索结果-南通市图书馆

Computational aerodynamic analysis on perimeter reinforced(PR)-compliant wing

Chinese Journal of Aeronautics 2013年第5期26卷 1093-1105页

作者： n.I.ismail A.H.Zulkifli M.Z.Abdullah M.Hisyam Basri norazharuddin Shah Abdullah Faculty of Mechanical Engineering Universiti Teknologi MARA40450 Shah AlamSelangorMalaysia School of Mechanical Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia School of Materials and Mineral Resources Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia

Abstract Implementing the morphing technique on a micro air vehicle （MAV） wing is a very chal- lenging task, due to the MAWs wing size limitation and the complex morphing mechanism. As a result, understanding aerodynamic characteristics and flow configurations, subject to wing structure deformation of a morphing wing MAV has remained obstructed. Thus, this paper presents the investigation of structural deformation, aerodynamics performance and flow formation on a pro- posed twist morphing MAV wing design named perimeter reinforced （PR）-compliant wing. The numerical simulation of two-way fluid structure interaction （FSI） investigation consist of a quasi- static aeroelastic structural analysis coupled with 3D incompressible Reynolds-averaged navier- Stokes and shear-stress-transport （RAnS-SST） solver utilized throughout this study. Verification of numerical method on a rigid rectangular wing achieves a good correlation with available exper- imental results. A comparative aeroelastic study between PR-compliant to PR and rigid wing per- formance is organized to elucidate the morphing wing performances. Structural deformation results show that PR-compliant wing is able to alter the wing＇s geometric twist characteristic, which has directly influenced both the overall aerodynamic performance and flow structure behavior. Despite the superior lift performance result, PR-compliant wing also suffers from massive drag penalty, which has consequently affected the wing efficiency in general. Based on vortices investigation, the results reveal the connection between these aerodynamic performances with vortices formation on PR-comoliant wing.

关键词： Aerodynamics Aeroelasticity Fluid structure interaction Micro air vehicle (MAV) Morphing wing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Estimating Loss Given Default Based on Beta Regression

引用

Computers, Materials & Continua 2021年第3期66卷 3329-3344页

作者： Jamil J.Jaber noriszura ismail Siti norafidah Mohd Ramli Baker Albadareen nawaf n.Hamadneh Department of Risk Management and Insurance The University of JordanAqaba77111Jordan Universiti Kebangsaan Malaysia Department of Mathematical SciencesMalaysia Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadh11673Saudi Arabia

Loss given default(LGD)is a key parameter in credit risk management to calculate the required regulatory minimum *** internal ratings-based(IRB)approach under the Basel II allows institutions to determine the loss given default(LGD)on their *** this study,we have estimated LGD for a credit portfolio data by using beta regression with precision parameter(∅)and mean parameter(μ).The credit portfolio data was obtained from a banking institution in Jordan;for the period of January 2010 untilDecember *** the first stage,we have used the“outstandingamount”and“amount of borrowing”to find LGD of each default borrower(494 out of 4393 borrower).In the second stage,we fit univariate parametric distributions to the LGD data to obtain the beta *** that,we have estimated the values of∅based on microeconomic variables(SPP,OE and LR).Moreover,we have estimated the values ofμbased on macroeconomic variables(GDP and Inflation rate).Finally,we have compared between six different link functions(Logit,loglog,probit,cloglog,cauchit,and log),which have used with∅andμ.The results show that Beta regression with probit link function has the highest R-squared with accepted measurements for logL,AIC and BIC.

关键词： Credit risk loss given default parametric distribution regression model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular characteristics,antibiogram and prevalence of multi-drug resistant Staphylococcus aureus (MDRSA) isolated from milk obtained from culled dairy cows and from cows with acute clinical mastitis

引用

Asian Pacific Journal of Tropical Biomedicine 2017年第8期7卷 694-697页

作者： Zuhair Bani ismail Department of Veterinary Clinical Sciences Faculty of Veterinary MedicineJordan University of Science and TechnologyIrbid22110Jordan

To study the molecular characteristics, antibiogram and prevalence of multi-drug resistant Staphylococcus aureus (S. aureus) (MDRSA) isolated from milk obtained from culled dairy cows and from cows with acute clinical *** were cultured from 188 quarter milk samples obtained from cows before culling (n = 139) and from cows affected with acute mastitis (n = 49) belonging to 10 dairy farms. The bacteria were identified using colony morphology, Gram staining and biochemical characteristics. S. aureus isolates were then subjected to molecular characterization using PCR targeting 16S rRnA and mecA gene to identify Methicillin resistant S. aureus (MRSA). The antibiogram of all isolates was performed using the Kirby-Bauer disk diffusion method against 10 commonly used antibiotics in dairy ***. aureus was isolated from 19 (13.7%) samples obtained from culled cows and 11 (22.4%) samples obtained from cows with acute mastitis. In both culled cows and cows with acute mastitis, in vitro antibiogram revealed that 100% of S. aureus isolates were resistant to erythromycin, penicillin G, streptomycin, doxycyclin, and trimethoprim/sulpha. The prevalence of MRSA in milk of culled cows and cows with acute mastitis was 26.3% and 18.2%, respectively, with an overall prevalence of 3.7% among all samples. All MRSA isolates were completely resistant to all tested antibiotics. All MRSA isolates were positive for the presence of the mecA *** carrying the mecA gene were isolated from mastitic milk from dairy cows in Jordan for the first time. MRSA may pose a potential health risk to the public, farm workers and veterinarians.

关键词： Antibiogram Mastitis pathogens Dairy cows Multi-drug resistance

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Direct C-H Bond Activation of Benzoxazole and Benzothiazole with Aryl Bromides Catalyzed by Palladium（Ⅱ）-n-heterocyclic Carbene Complexes

引用

Chinese Journal of Chemistry 2018年第9期36卷 837-844页

作者： Murat Kaloglu nazan Kaloglur ismail Ozdemir Department of Chemistry Faculty of Science and Arts inonu University 44280 Malatya Turkey Catalysis Research and Application Center inonu University 44280Malatya Turkey

Herein, we report that a series of novel palladium（II）-nHC complexes （nHC=n-heterocyclic carbene） were synthesized. The structures of all novel complexes were characterized by ^1H nMR, ^13C nMR, FT-IR spectroscopy and elemental analysis techniques. These palladium（ll）-nHC complexes were tested as efficient catalysts in the direct C-H bond activation of benzoxazole and benzothiazole with aryl bromides in the presence of 1 mol% catalyst loading at 150 ℃ for 4 h. Under the given conditions, various aryl bromides were successfully applied as the arylating reagents to achieve the 2-arylbenzoxazoles and 2-arylbenzothiazoles in acceptable to high yields.

关键词： benzimidazolium bromide benzoazoles direct C-H bond activation n-heterocyclic carbene palladium

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transition Metal Dichalcogenides(WS2 and MoS2)Saturable Absorbers for Mode-Locked Erbium-Doped Fiber Lasers

引用

Chinese Physics Letters 2017年第1期34卷 48-51页

作者： n.A.A.Kadir E.I.ismail A.A.Latiff H.Ahmad H.Arof S.W.Harun Department of Electrical Engineering Faculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia Photonics Research Center University of MalayaKuala Lumpur 50603Malaysia

We demonstrate an ultrafast fiber laser based on transition metal dichalcogenide materials which are tungsten disulfide (WS2) and molybdenum disulfide (MoS2) as saturable absorber (SA). These materials are fabricated via a simple drop-casting method. By employing WS2, we obtain a stable harmonic mode-locking at the threshold pump power of 184 mW, and the generated soliton pulse has 3.48 MHz of repetition rate. At the maximum pump power of 250 mW, we also obtain a small value of pulse duration, 2.43 ps with signal-to-noise ratio (SnR) of 57 dB. For MoS2 SA, the pulse is generated at 105 mW pump power with repetition rate of 1.16 MHz. However, the pulse duration cannot be detected by the autocorrelator device as the pulse duration recorded is 468 ns, with the SnR value of 35 dB.

关键词： WS2 and MoS2 SA Transition Metal Dichalcogenides Saturable Absorbers for Mode-Locked Erbium-Doped Fiber Lasers

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Stefan blowing effect on bioconvective flow of nanofluid over a solid rotating stretchable disk

引用

Propulsion and Power Research 2016年第4期5卷 267-278页

作者： n.A.Latiff M.J.Uddin A.I.Md.ismail School of Mathematical Sciences Universiti Sains MalaysiaPenang 11800Malaysia

A mathematical model for the unsteady forced convection over rotating stretchable disk in nanofluid containing microorganisms and taking into account Stefan blowing effect is presented theoretically and *** transfonnations are used to transform the governing boundary layer equations into non-linear ordinary differential equations,before being solved numerically using the Runge-Kutta-Fehlberg *** effect of the governing parameters on the dimensionless velocities,temperature,nanoparticle volume fraction(concentration),density of motile microorganisms as well as on the local skin friction,local nusselt,Sherwood number and motile microorganisms numbers are thoroughly examined via *** is observed that the Stefan blowing increases the local skin friction and reduces the heat transfer,mass transfer and microorganism transfer *** numerical results are in good agreement with those obtained from previous *** quantities results from this investigation show that the effects of higher disk stretching strength and suction case provides a good medium to enhance the heat,mass and microorganisms transfer compared to blowing case.

关键词： Stefan blowing Bio-nanofluid Stretching disk Rotating disk Heat transfer

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Influence of alkaline treatment and fiber loading on the physical and mechanical properties of kenaf/polypropylene composites for variety of applications

引用

Progress in natural Science:Materials International 2016年第6期26卷 657-664页

作者： Majid niaz Akhtar Abu Bakar Sulong M.K.Fadzly Radzi n.F.ismail M.R.Raza norhamidi Muhamad Muhammad Azhar Khan Department of Physics COMSATS Institute of Information Technology Department of Mechanical and Materials Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia Department of Basic Sciences and Humanities Muhammad Nawaz Sharief University of Engineering and Technology(MNSUET) Department of Mechanical Engineering COMSATS Institute of Information Technology Department of Physics The Islamia University of Bahawalpur

Due to current trend and increasing interest towards natural based fiber products, Kenaf(Hibiscus cannabinus)fibers have been used for the developments of many products. Therefore, Kenaf fiber-reinforced composites have been widely used in engineering and industrial applications. The present work deals with the fabricating and characterization of untreated and treated kenaf/polypropylene(PP)-reinforced composites. Composites of PP reinforced with treated and untreated kenaf fibers were fabricated using the injection molding *** fiber loadings of 10, 20, 30, 40, 50 wt% treated and untreated kenaf composites were also prepared. Xray diffraction(XRD), scanning electron microscopy(SEM), Fourier transform infrared(FTIR) spectroscopy and thermo gravimetric analysis(TGA) were performed on the treated, untreated kenaf fibers and kenaf/PP composites. Moreover, the alkaline-treated kenaf composites exhibit better physical, morphological, and mechanical properties because of the compatibility of kenaf with PP. However, variations in tensile and flexural properties depend on treatment and kenaf fiber contents. The percentage increase in the mechanical properties of the treated kenaf/PP composites relative to that of PP was also measured. In addition, 40 wt%kenaf fiber loading resulted in higher mechanical properties. By contrast, kenaf/PP composite with 50% fiber loading was not successfully prepared because of improper mixing and the burning of kenaf fibers in the PP matrix. To conclude, 40% kenaf/PP composites with superior physical and mechanical properties may be used in variety of applications such as automotive, sports, construction, animal bedding, and mass production industries.

关键词： Kenaf composites Microstructures Physical properties Mechanical Testing Injection-molding

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

n-Body Simulation Inspired by Metaheuristics Optimization

引用

Computer Systems Science & Engineering 2022年第6期41卷 1143-1155页

作者： Muhammad Ali ismail Maria Waqas Farah Sadiq national Center in Big Data and Cloud Computing Department of Computer and Info Systems EngineeringNED University of Engineering and TechnologyKarachiPakistan

The n-body problem in classical physics, is the calculation of force ofgravitational attraction of heavenly bodies towards each other. Solving this problem for many heavenly bodies has always posed a challenge to physicists andmathematicians. Large number of bodies, huge masses, long distances and exponentially increasing number of equations of motion of the bodies have been themajor hurdles in solving this problem for large and complex galaxies. Adventof high performance computational machines have mitigated the problem to muchextent, but still for large number of bodies it consumes huge amount of resourcesand days for computation. Conventional algorithms have been able to reduce thecomputational complexity from O n2 ð Þ to O nlogn ð Þ by splitting the space into atree or mesh network, researchers are still looking for improvements. In thisresearch work we propose a novel solution to n-body problem inspired by metaheuristics algorithms. The proposed algorithm is simulated for various time periods of selected heavenly bodies and analyzed for speed and accuracy. Theresults are compared with that of conventional algorithms. The outcomes showabout 50% time saving with almost no loss in accuracy. The proposed approachbeing a metaheuristics optimization technique, attempts to find optimal solution tothe problem, searching the entire space in a unique and efficient manner in a verylimited amount of time.

关键词： n-body problem metaheuristics optimization particle swarm optimization heavenly bodies

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Evaluation of DnA damage profile in obese women and its association to risk of metabolic syndrome,polycystic ovary syndrome and recurrent preeclampsia

引用

Genes & Diseases 2018年第4期5卷 367-373页

作者： Moushira Zaki walaa Basha Hala T.El-Bassyouni Safinaz El-Toukhy Tamer Hussein Biological Anthropology Department Medical Research DivisionNational Research CentreCairoEgypt Clinical Genetics Department National Research CentreCairoEgypt Medical Biochemistry Department Medical Research DivisionNational Research CentreCairoEgypt Reproductive Health Research Department Medical Research DivisionNational Research CentreCairoEgypt

Metabolic syndrome(MS)is a cluster of metabolic *** and MS are always accompanied by elevated oxidative stress which might affect cellular biomolecules such as *** aim of the present study is to investigate DnA damage profile in obese premenopausal women and its relation to the risk of MS,polycystic ovary syndrome(PCOS)and history of recurrent *** study included 90 obese women included cases with MS(nZ30),PCOS(n Z30)and previous history of recurrent preeclampsia(nZ30)and,age-matched healthy non-obese control women(n Z 50).The assessment of leukocyte DnA damage was done by comet assay for all cases and *** and biochemical parameters have been *** showed that mean percent of DnA damage was significantly higher in MS,PCOS as well as in women with the recurrent preeclampsia as compared to healthy *** high level of mean DnA damage frequency in obese women was significantly associated with the increased number of metabolic syndrome *** with 2,3 and 3e5 components showed significantly higher levels of DnA damage than ***,cases with 3e5 MS components showed significant higher DnA compared to those with the two *** PCOS,significant positive association between the mean frequency of DnA damage and waist circumference was *** study suggests that metabolic abnormalities,PCOS and recurrent pre-eclampsia might be contributed in development of DnA damage in obese *** damage can serve as an early marker for obesity complications in premenopausal women.

关键词： DnA damage Metabolic components Obesity PCOS Recurrent preeclampsia

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Controlled multilevel switching and artificial synapse characteristics in transparent HfAlO-alloy based memristor with embedded Tan nanoparticles

引用

Journal of Materials Science & Technology 2021年第36期95卷 203-212页

作者： Chandreswar Mahata Hassan Algadi Muhammad ismail Daewoong Kwon Sungjun Kim Division of Electronics and Electrical Engineering Dongguk UniversitySeoul 04620Republic of Korea Department of Electrical Engineering Faculty of EngineeringNajran UniversityP.O.Box 1988Najran 11001Saudi Arabia Department of Electrical Engineering Inha UniversityIncheonRepublic of Korea

Atomic layer deposition technique has been used to prepare tantalum nitride nanoparticles(Tan-nPs)and sandwiched between Al-doped HfO;layers to achieve ITO/HfAlO/Tan-nP/HfAlO/ITO RRAM *** electron microscopy along with energy dispersive spectroscopy confirms the presence of Tan-nPs.X-ray photoelectron spectroscopy suggests that part of Ta n converted to tantalum oxynitride(TaO_(x)n_(y))which plays an important role in stable cycle-to-cycle resistive *** trapping and oxygen vacancy creation were found to be modified after the inclusion of Ta n-nPs inside RRAM ***,HfAlO/TaO_(x)n_(y)interface due to the presence Tan-nPs improves the device-to-device switching reliability by reducing the probability of random rupture/formation of conductive filaments(CFs).DC endurance of more than 10^(3)cycles and memory data retention up to 10^(4)s was achieved with an insignificant variation of different resistance *** conductance was attained by controlling RESET voltage with stable data retention in multiple *** volatile threshold switching was monitored after controlling the CF forming at 200 nA current compliance with high selectivity of~10^(3).Synaptic learning behavior has been demonstrated by spike-rate-dependent plasticity(SRDP).Reliable potentiation and depression processes were observed after the application of suitable negative and positive pulses which shows the capability of the Tan–nPs based RRAM device for transparent synaptic devices.

关键词： RRAM ALD Tan-nanoparticles Threshold switching Spike-rate-dependent plasticity Multilevel conductance Synaptic properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：