检索结果-南通市图书馆

Deep Stack.d Ensemble Learning Model for COVID-19 Classification

Computers, Materials & Continua 2022年第3期70卷 5467-5486页

作者： G.Madhu B.Lalith Bharadwaj Rohit Boddeda Sai Vardhan k.Sandeep k.utish khalid Alnowibet Adel F.Alrasheedi ali Wagdy Mohamed Department of Information Technology VNRVJIETHyderabad500090India Department of Computer Science and Engineering VNRVJIETHyderabad500090India LBEF Campus Kathmandu44600Nepal Statistics and Operations Research Department College of ScienceKing Saud UniversityRiyadh11451Kingdom of Saudi Arabia Operations Research Department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Wireless Intelligent Network. Center(WINC) School of Engineering and Applied SciencesNile UniversityGiza12588Egypt

COVID-19 is a growing problem worldwide with a high mortality *** a result,the World Health Organization(WHO)declared it a *** order to limit the spread of the disease,a fast and accurate diagnosis is required.A reverse transcript polymerase chain reaction(RT-PCR)test is often used to detect the ***,since this test is time-consuming,a chest computed tomography(CT)or plain chest X-ray(CXR)is sometimes *** value of automated diagnosis is that it saves time and money by minimizing human *** significant contributions are made by our *** initial purpose is to use the essential finetuning methodology to test the action and efficiency of a variety of vision models,ranging from Inception to Neural Architecture Search(NAS)***,by plotting class activationmaps(CAMs)for individual network. and assessing classification efficiency with AUC-ROC curves,the behavior of these models is visually ***,stack.d ensembles techniques were used to provide greater generalization by combining finetuned models with six ensemble neural *** stack.d ensembles,the generalization of the models ***,the ensemble model created by combining all of the finetuned network. obtained a state-of-the-art COVID-19 accuracy detection score of 99.17%.The precision and recall rates were 99.99%and 89.79%,respectively,highlighting the robustness of stack.d *** proposed ensemble approach performed well in the classification of the COVID-19 lesions on CXR according to the experimental results.

关键词： COVID-19 classification class activation maps(CAMs)visualization finetuning stack.d ensembles automated diagnosis deep learning

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

Numerical simulation of compression corner flows at Mach number 9

引用

Chinese Journal of Aeronautics 2020年第6期33卷 1611-1624页

作者： Amjad APASHA khalid AJUHANY Department of Aerospace Engineering King Abdulaziz UniversityJeddah 21589Saudi Arabia

A hypersonic vehicle encounters a wide range of conditions during its complete flight *** flight conditions may vary from low to high Mach numbers with varying angles of *** near-wall viscous dissipation associated with flows at combined high Mach and Reynolds numbers leads to significant wall heat transfer rates and shear *** shock.wave/boundary-layer interaction results in a flow separation region,which commonly augments total pressure losses in the flow and lowers the efficiency of aerodynamic control surfaces such as fins installed on a *** standard turbulence models,when used to resolve such flows,result in incorrect separation bubble size for large separated ***,it results in an inaccurate aerodynamic load,such as the wall pressures,sk.n friction distribution,and heat transfer *** previous studies,the application of the shock.unsteadiness correction to the standard two-equation k.ωturbulence model improved the separation bubble size leading to an accurate pressure prediction and shock.definition with the assumption of constant Prandtl *** the present work.the new shock.unsteadiness modification to the k.ωturbulence model is applied to the hypersonic compression corner *** new model with variable Prandtl number is based on the model parameter,which depends upon the local density *** computed wall pressures,heat flux and flow field are compared to the experimental data.A parametric study is carried out by varying compression deflection angles,free stream Reynolds number and wall temperatures to compute the flow field and wall data accurately,particularly in the shock.boundary layer interaction *** new shock.nsteadiness modified k.ωmodel with variable Prandtl number shows an accurate prediction of initial pressure rise location,pressure distribution in the plateau region and heat flux in comparison to the standard k.ωmodel.

关键词： Boundary layer Expansion fan Heat transfer Hypersonic flows Separation length Shock.unsteadiness model Shock.wave Turbulence model Turbulent Prandtl number

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

Tailoring the optical and magnetic properties of La-BaM hexaferrites by Ni substitution

引用

Chinese Physics B 2022年第2期31卷 570-575页

作者： Hafiz T.ali MRamzan M Imran Arshad Nicola A.Morley M.Hassan Abbas Mohammad Yusuf Atta Ur Rehman khalid Mahmood Adnan ali Nasir Amin MAjaz-un-Nabi Department of Mechanical Engineering College of EngineeringTaif UniversityTaif 21944Saudi Arabia Department of Physics Government College UniversityFaisalabadPakistan Department of Materials Science and Engineering University of SheffieldSir Robert Hadfield BuildingMapping St.SheffieldS13JDUK Department of Clinical Pharmacy College of PharmacyTaif UniversityTaif 21944Saudi Arabia

We investigate the impact of Ni insertion on the structural,optical,and magnetic properties of Ba_(0.8)La_(0.2)Fe_(12-x)Ni_(x)O_(19)hexaferrites(Ni substituted La-BaM hexaferrites).Samples were prepared using the conventional co-precipitation method and sintered at 1000℃for 4 hours to assist the crystallization *** analysis of the structure of the samples was carried out using an x-ray diffraction(XRD)*** M-type hexagonal structure of all the samples was confirmed using XRD *** lattice parameters a and c were found to be in the ranges of 5.8925±0.001 nm–5.8952±0.001 nm and 23.2123±0.001 nm–23.2219±0.001 nm,*** M-type hexagonal nature of the prepared samples was also indicated by the presence of corresponding FT-IR bands and Raman modes in the FT-IR and Raman spectra,*** results confirmed the successful synthesis of the samples according to the required stoichiometric ratio.A UV-vis spectrometer was used to record the absorption spectra of the prepared samples in the wavelength range of 200 nm–1100 *** optical energy bandgap of the samples was found to be in the range of 1.21 eV–3.39 *** M–H loops of the samples were measured at room temperature at an applied magnetic field range of 0 k.e–60 k.e.A high saturation magnetization of 99.92 emu/g was recorded in the sample with x=0 at a microwave operating frequency of 22.2 *** high value of saturation magnetization is due to the substitution of La3+ions at the spin-up(12k.2a,and 2b)*** Ni substitution is proven to be a potential candidate for the tuning of the optical and magnetic parameters of M-type ***,we suggest that the prepared samples are suitable for use in magneto-optic applications.

关键词： M-type hexaferrite nanostructured materials magnetic properties optical 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

Hepatitis C virus non-structural 5A protein can enhance full-length core protein-induced nuclear factor-κB activation

引用

World Journal of Gastroenterology 2005年第41期11卷 6433-6439页

作者： khalid Amine Timani State k.y Laboratory of Virology College of Life Sciences Wuhan UniversityWuhan 430072Hubei ProvinceChina

AIM： To study the effects of hepatitis C virus （HCV） core and non-structural 5A （NS5A） proteins on nuclear factor- k.B （NF- k.B） activity for understanding their biological function on chronic hepatitis caused by HCV infection. METHODS： Luciferase assay was used to measure the activity of NF-k. in three different cell lines cotransfected with a series of deletion mutants of core protein alone or together with NS5A protein using pNF- k.B-Luc as a reporter plasmid. Western blot and indirect immunofluorescence assays were used to confirm the expression of proteins and to detect their subcellular localization, respectively. Furthermore, Western blot was also used to detect the expression levels of NF- k.B/p65, NF- k.B/p50, and inhibitor k.B-a（k.B-a）. RESULTS： The wild-type core protein （C191） and its mutant segments （C173 and C158） could activate NF- k.B in Huh7 cells only and activation caused by （C191） could be enhanced by NS5A protein. Moreover, the full-length core protein and its different deletion mutants alone or together with NS5A protein did not enhance the expression level of NF- k.B. The NF- k.B activity was augmented due to the dissociation of NF-k. B-I k. B complex and the degradation of Ik.B-a. CONCLUSION：NF- k.B is the k.y transcription factor that can activate many genes that are involved in the cellular immune response and inflammation. Coexpression of the full-length core protein along with NS5A can enhance the NF- k.B activation, and this activation may play a significant role in chronic liver diseases including hepatocellular carcinoma associated with HCV infection.

关键词： HCV NS5A Core protein NF- k.B

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 graphene nanoplatelets on mechanical properties and adhesive wear performance of epoxy-based composites

引用

Friction 2021年第4期9卷 856-875页

作者： k.Y.EAYAL AWWAD B.F.YOUSIF k.osro FALLAHNEZHAD khalid SALEH Xuesen ZENG Faculty of Health Engineering and SciencesUniversity of Southern QueenslandToowoombaQLDAustralia Centre for Future Materials University of Southern QueenslandToowoombaQLDAustralia School of Mechanical and Mining Engineering University of QueenslandBrisbaneQLDAustralia

Epoxy resin is one of the most widely used thermoset polymers in high-performance composite materials for lightweight ***,epoxy has a high coefficient of friction,which limits its tribological *** this study,the effect was investigated of different weight fractions of solid lubricant graphene nanoplatelets(GNPs),ranging from 0 to 4.5 wt%,on mechanical and adhesive wear performance of *** wear tests covered mild and severe wear *** correlation of tribological and mechanical properties was studied as *** electron microscopy(SEM)was used to observe the failure mechanisms for both tribological and mechanical samples after each *** results revealed that the addition of GNPs to the epoxy improved its stiffness and hardness but reduced its fracture strength and *** wear performance exhibited high efficiency with GNP additions and showed reductions in the specific wear rate,the coefficient of friction,and the induced interface temperature by 76%,37%,and 22%,respectively.A fatigue wear mechanism was predominant as the applied load *** importantly,severe wear signs occurred when the interface temperature reached the heat distortion temperature of the *** tribological,and mechanical properties showed only a weak.correlation to each *** addition of GNPs to epoxy by less than 4.5 wt%was highly efficient to improve the wear performance while maintaining the fracture strength and *** transform infrared spectroscopy(FTIR)analysis shows no chemical interaction between the epoxy matrix with GNPs,which implies its physical interaction.

关键词： graphene nanoplatelets epoxy adhesive wear solid lubricants

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

Modulating microRNAs in cancer: next-generation therapies

引用

Cancer Biology & Medicine 2022年第3期19卷 289-304页

作者： Nahid Arghiani khalid Shah Center for Stem Cell and Translational Immunotherapy(CSTI) Harvard Medical SchoolBostonMA 02115USA Department of Neurosurgery Brigham and Women’s HospitalHarvard Medical SchoolBostonMA 02115USA Harvard Stem Cell Institute Harvard UniversityCambridgeMA 02138USA

MicroRNAs(miRNAs)are a class of endogenously expressed non-coding regulators of the genome with an ability to mediate a variety of biological and pathological *** is growing evidence demonstrating frequent dysregulation of microRNAs in cancer cells,which is associated with tumor initiation,development,migration,invasion,resisting cell death,and drug *** have shown that modulation of these small RNAs is a novel and promising therapeutic tool in the treatment of a variety of diseases,especially cancer,due to their broad influence on multiple cellular ***,suboptimal delivery of the appropriate miRNA to the cancer sites,quick.degradation by nucleases in the blood circulation,and off target effects have limited their research and clinical ***,there is a pressing need to improve the therapeutic efficacy of miRNA modulators,while at the same time reducing their *** delivery vehicles for miRNA modulators have been shown to be effective in vitro and in *** this review,we will discuss the role and importance of miRNAs in cancer and provide perspectives on currently available carriers for miRNA *** will also summarize the challenges and prospects for the clinical translation of miRNAbased therapeutic strategies.

关键词： MiRNAs dysregulation delivery systems cancer therapy clinical translation

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

Impact of soil compaction on the engineering properties of potato tubers

引用

International Journal of Agricultural and Biological Engineering 2020年第2期13卷 163-167页

作者： Mohamed k.Edrris khalid A.Al-Gaadi Abdalhaleem A.Hassaballa Elk.mil Tola khalid A.M.Ahmed Precision Agriculture Research Chair King Saud UniversityRiyadh 11451Saudi Arabia Department of Agricultural Engineering College of Food and Agriculture SciencesKing Saud UniversityRiyadh 11451Saudi Arabia Department of Agricultural&Biological Engineering Faculty of EngineeringKhartoum UniversityKhartoumSudan Chair of Dates Industry and Technology King Saud UniversityRiyadh 11451Saudi Arabia

A study on a 30 hm2 field was conducted to assess the variability in soil compaction and to investigate its effect on the engineering properties of potato tubers in terms of tuber shape and k.y dimensions(length,width and thick.ess)and resistance to penetration,rupture and shear *** soil compaction levels were spatially correlated with the engineering properties of potato tubers through linear regression and ANOVA *** three compaction levels included a low level(C1)ranging between 1.2-1.9 MPa,a medium level(C2)with compaction levels between 2.0-2.3 MPa and a high level(C3)ranging between 2.4-2.9 *** revealed that there were no significant changes in the k.y tuber dimensions corresponding to the variability in soil ***,inverse linear relationships were observed between soil compaction and the k.y tuber dimensions with R2 values of 77%,97%and 96%for length,width and thick.ess,***,the soil compaction was shown to have no effect on the tuber resistance to compression and shear *** contrast,the tuber resistance to penetration was significantly affected by soil compaction(p>F=0.0012).

关键词： compaction potato tubers precision agriculture potato engineering properties

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

Effect　of　Ballistic-Type　Hot　Atom　Adsorption　Mechanism　on　the　Phase　Diagram　of　Monomer　Dimer　CO-O2　Surface　Catalytic　Reaction：　A　Monte　Carlo　Simulation

引用

Chinese Physics Letters 2004年第6期21卷 1171-1174页

作者： M.khalid k.M.k.an A.U.Qaisrani Q.N.Malik DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan NuclearPhysicsDivision PakistanInstituteofNuclearScienceandTechnology(PINSTECH)P.O.NiloreIslamabadPakistan

We investigate the effect of the ballistic mechanism on the phase diagram using a square surface. While using this mechanism whenever an O2 molecule hits a randomly vacant selected site, the molecule break. up into atomic form and then executes a ballistic flight. The paths of the two oxygen atoms are tak.n exactly to be opposite to each other, i. e. anti-parallel, and the ranges of the atoms are tak.n to be equal, i. e.~they may fly up to 1 or 1.414 or 2 of the atomic spacing from the site of impact. Four cases have been studied on the basis of the range of hot atoms. The range of the hot oxygen atoms executing a ballistic flight might be up to the first nearest neighbourhood (1 atomic spacing from the site of impact), the second nearest neighbourhood (1.414 atomic spacing from the site of impact), the third nearest neighbourhood (2 atomic spacing from the site of impact), k.own as cases a, b, and c, respectively, while for case d the range of the oxygen atoms executing the ballistic flight might be up to 1 atomic spacing or 1.414 atomic spacing or 2 atomic spacing from the site of impact. The steady reactive window is observed and the continuous transition disappears. As soon as the CO partial pressure departs from zero, the production of CO2 is observed, which clearly verifies the experimental observation.

关键词： Oxygen

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

Range-Based Localization in Wireless Network. Using Density-Based Outlier Detection

引用

Wireless Sensor Network 2010年第11期2卷 807-814页

作者： khalid k. Almuzaini Aaron Gulliver 不详

Node localization is commonly employed in wireless network.. For example, it is used to improve routing and enhance security. Localization algorithms can be classified as range-free or range-based. Range-based algorithms use location metrics such as ToA, TDoA, RSS, and AoA to estimate the distance between two nodes. Proximity sensing between nodes is typically the basis for range-free algorithms. A tradeoff exists since range-based algorithms are more accurate but also more complex. However, in applications such as target track.ng, localization accuracy is very important. In this paper, we propose a new range-based algorithm which is based on the density-based outlier detection algorithm (DBOD) from data mining. It requires selection of the k.nearest neighbours (k.N). DBOD assigns density values to each point used in the location estimation. The mean of these densities is calculated and those points having a density larger than the mean are k.pt as candidate points. Different performance measures are used to compare our approach with the linear least squares (LLS) and weighted linear least squares based on singular value decomposition (WLS-SVD) algorithms. It is shown that the proposed algorithm performs better than these algorithms even when the anchor geometry about an unlocalized node is poor.

关键词： Localization Positioning Ad Hoc Network. Range-Based Wireless Sensor Network Outlier Detection Clustering

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

Experimental Behavior of Partially Prestressed High Strength Concrete Beams

引用

Open Journal of Civil Engineering 2013年第3期3卷 26-32页

作者： Shady H. Salem khalid M. Hilal Tarek.k. Hassan Ahmed S. Essawy Department of Structural Engineering Faculty of Engineering Ain Shams University Cairo Egypt

In the last few decades, prestressed concrete has been rapidly used in bridge engineering due to the enormous development in the construction techniques and the increasing need for long span bridges. High strength concrete has been also more widely spread than the past. It currently becomes more desirable as it has better mechanical properties and durability performance. Major defect of fully prestressed concrete is its low ductility;it may produce less alarming signs than ordinary reinforced concrete via smaller deflection and limited crack.ng. Therefore, partially prestressing is considered an intermediate design between the two extremes. So, combining high strength concrete with partial prestressing will result in a considerable development in the use of prestressed concrete structures regarding the economical and durability view points. This study presents the results of seven partially prestressed high strength concrete beams in flexure. The tested beams are used to investigate the influence of concrete compressive strength, prestressing steel ratio and flange width on the behavior of partially prestressed beams. The experimentally observed behaviors of all beams were presented in terms of the crack.ng load, ultimate load, deflection, crack.ng behavior and failure modes.

关键词： Partially Prestressed High Strength Concrete Beams Serviceability Behavior Failure Modes

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

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：