检索结果-南通市图书馆

Wearable UWB Antenna-Based Bending and Wet Performances for Breast Cancer Detection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第12期73卷 5575-5587页

作者： ali Hanafiah Rambe Muzammil Jusoh samir salem.al-bawri Mahmoud A.Abdelghany Department of Electrical Engineering Universitas Sumatera UtaraMedan20155Indonesia Advanced Communication Engineering(ACE) Centre of ExcellenceFaculty of Electronic Engineering TechnologyUniversiti Malaysia PerlisMalaysia Department of General Educational Development Faculty of Science and Information Technology(FSIT)Daffodil International UniversityDhaka1341Bangladesh Space Science Centre Climate Change InstituteUniversiti Kebangsaan MalaysiaBangiMalaysia Department of Electronics and Communication Engineering Faculty of EngineeringHadhramout UniversityAl-MukallaYemen Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Department of Electrical Engineering Faculty of EngineeringMinia UniversityMinia61519Egypt

This paper proposed integrating the communication system on the garment,which can be utilized to detect breast cancer at an early stage by using an ultra-wideband(UWB)wearable *** cancer is an abnormal cell that is located in the breast *** detection of breast cancer plays an important role,and it helps in the long term for all *** proposed UWB wearable antenna successfully operates at 3.1-10.6 GHz under an acceptable reflection coefficient of−10 *** fabricated wearable antenna was made from Shieldit Super and felt both conductive and nonconductive wearable *** measurement studies of bending angles have been carried out that covered 2°,4°,6°,8°,and 10°.In addition,the performance of UWB antennas in wet environments is studied in four stages:in water,instantly wet,nearly dry,and entirely *** is good agreement between the measured and simulated *** on the experimental results,the proposed antenna could be helpful for a home breast cancer detection system.

关键词： Wearable antenna UWB antenna bioelectromagnetic antenna propagation

Manipulating Nb-doped SrFeO_(3−δ)with excellent performance for proton-conducting solid oxide fuel cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2024年第5期13卷 579-589页

作者： Hailu Dai Hongzhe Du samir Boulfrad Shoufu Yu Lei Bi Qinfang Zhang School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China College of Science&Engineering Hamad Bin Khalifa UniversityDoha 34110Qatar School of Resource Environment and Safety Engineering University of South ChinaHengyang 421001China

Nb-doped SrFeO_(3−δ)(SFO)is used as a cathode in proton-conducting solid oxide fuel cells(H-SOFCs).First-principles calculations show that the SrFe0.9Nb0.1O_(3−δ)(SFNO)cathode has a lower energy barrier in the cathode reaction for H-SOFCs than the Nb-free SrFeO_(3−δ)*** experimental studies show that Nb doping substantially enhances the performance of the SrFeO_(3−δ)***,oxygen vacancies(VO)were introduced into SFNO using the microwave sintering method,further improving the performance of the SFNO *** mechanism behind the performance improvement owing to VO was revealed using first-principles calculations,with further optimization of the SFNO cathode achieved by developing a suitable wet chemical synthesis route to prepare nanosized SFNO *** method significantly reduces the grain size of SFNO compared with the conventional solid-state reaction method,although the solid-state reaction method is generally used for preparing Nb-containing *** a result of defect engineering and synthesis approaches,the SFNO cathode achieved an attractive fuel cell performance,attaining an output of 1764 mW·cm−2 at 700℃ and operating for more than 200 *** manipulation of Nb-doped SrFeO_(3−δ)can be seen as a“one stone,two birds”strategy,enhancing cathode performance while retaining good stability,thus providing an interesting approach for constructing high-performance cathodes for H-SOFCs.

关键词： SrFeO_(3−δ)-(SFO) cathode proton conductor solid oxide fuel cells(SOFCs)

An efficient improved Gradient Boosting for strain prediction in Near-Surface Mounted fiber-reinforced polymer strengthened reinforced concrete beam

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第8期18卷 1148-1168页

作者： Abdelwahhab KHATIR Roberto CAPOZUCCA samir KHATIR Erica MAGAGNINI Brahim BENAISSA Thanh CUONG-LE Structural Section DICEA Polytechnic University of MarcheAncona 60131Italy Centre for Engineering Application&Technology Solutions Ho Chi Minh City Open UniversityHo Chi Minh City 70000Vietnam Design Engineering Laboratory Toyota Technological InstituteNagoya 468-8511Japan

The Near-Surface Mounted(NSM)strengthening technique has emerged as a promising alternative to traditional strengthening methods in recent *** the past two decades,researchers have extensively studied its potential,advantages,and applications,as well as related parameters,aiming at optimization of construction ***,there is still a need to explore further,both from a static perspective,which involves accounting for the nonconservation of the contact section resulting from the bond-slip effect between fiber-reinforced polymer(FRP)rods and resin and is typically neglected by existing analytical models,as well as from a dynamic standpoint,which involves studying the trends of vibration frequencies to understand the effects of various forms of damage and the efficiency of *** address this gap in knowledge,this research involves static and dynamic tests on simply supported reinforced concrete(RC)beams using rods of NSM carbon fiber reinforced polymer(CFRP)and glass fiber reinforced polymer(GFRP).The main objective is to examine the effects of various strengthening *** research conducts bending tests with loading cycles until failure,and it helps to define the behavior of beam specimens under various damage degrees,including concrete *** analysis by free vibration testing enables tracking of the effectiveness of the reinforcement at various damage levels at each stage of the loading *** addition,application of Particle Swarm Optimization(PSO)and Genetic algorithm(GA)is proposed to optimize Gradient Boosting(GB)training performance for concrete strain prediction in NSM-FRP *** GB using Particle Swarm Optimization(GBPSO)and GB using Genetic algorithm(GBGA)systems were trained using an experimental data set,where the input data was a static applied load and the output data was the consequent *** models of GBPSO and GBGA have been shown to provide highly accurate results for predicting *** model

关键词： NSM technique fiber-reinforced polymer rods static and dynamic analysis GB PSO GA finite element analysis

Left-Handed Characteristics Tunable C-Shaped Varactor Loaded Textile Metamaterial for Microwave Applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第4期71卷 611-628页

作者： samir salem.al-bawri Mohammad Tariqul Islam Kabir Hossain Thennarasan Sabapathy Muzammil Jusoh Space Science Centre Climate Change InstituteUniversiti Kebangsaan MalaysiaBangi43600Malaysia Department of Electrical Electronic and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaUKMBangi43600SelangorMalaysia Advanced Communication Engineering(ACE) Centre of ExcellenceUniversiti Malaysia Perlis(UniMAP)PerlisMalaysia Faculty of Electronic Engineering Technology Universiti Malaysia Perlis(UniMAP)PerlisMalaysia

This paper presents a textile-based C-shaped split-ring resonators(SRR)metamaterial(MTM)unit cells with an electrical tunability *** proposed MTM was composed of two symmetrical C-shaped SRR combined with a central diagonal metal bar,whereas the RF varactor diode is placed on the backside of the splitted ground *** behavior of single and array MTM unit cells were analyzed while the achieved negative index physical characteristics were widely *** four different MTM arrays(i.e.,1×1,1×2,2×1,and 2×2)were analyzed in simulation,a 2×2-unit cell array was chosen to fabricate,and it was further undergone experimental *** proposed tunable MTM exhibits double negative(DNG)/left-handed properties with an average bandwidth of more than 2.8 ***,attainable negative permittivity and negative permeability are within 2.66 to 9.59 GHz and within 2.77 to 15 GHz,respectively,at the frequency of interest(between 1 and 15 GHz).Moreover,the proposed tunable MTM also showed tunable transmission coefficient *** proposed electrically tunable textile MTM might function in a dynamic mode,making it suitable for a variety of microwave-wearable applications.A satisfactory agreement between simulations and experiments were achieved,demonstrating that the proposed MTM can operate over a wide bandwidth.

关键词： Textile metamaterial metamaterial wearable antennas tunable metamaterials metasurface antennas DNG metamaterials

Controlled Synthesis of Bismuth Oxyhalides-based Nanomaterials and Their Catalytic Applications

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 Synthesis of Bismuth Oxyhalides-based Nanomateria...

作者： Ahmad samir Karimi Haqmal 北京化工大学

学位级别：硕士

卤氧化铋(BiOX,X=Cl、Br或I)因其独特的结构特性,如二维层状结构和大量暴露的表面原子,而受到广泛关注。这些特性使它们成高效的光催化剂,并被广泛应用于水处理、有机合成等领域。然而,它们在其他催化中的潜力,如作为金属铋的前体或作... 详细信息

卤氧化铋(BiOX,X=Cl、Br或I)因其独特的结构特性,如二维层状结构和大量暴露的表面原子,而受到广泛关注。这些特性使它们成高效的光催化剂,并被广泛应用于水处理、有机合成等领域。然而,它们在其他催化中的潜力,如作为金属铋的前体或作为单原子催化剂的载体,还处于起步阶段。在本论文中,我们研究了卤素离子和形貌对以卤氧化铋为前驱体合成的金属铋电催化剂的结构的影响,及其在氮还原反应(NRR)中的性能,并以氯氧化铋为载体制备了 Pt单原子催化剂,探究了其在苯乙炔反马仕加成硅氢化反应中的催化性能。本论文取得的主要研究成果如下:在第一个工作中,我们发展了一种电还原卤氧化铋制备的金属铋纳米片(BNSs)的合成方法,并将其应用于电催化氮还原反应(NRR)。BNSs可分别由具有不同卤素离子的卤氧化铋纳米片前体以及溴氧化铋纳米棒制备的。X射线衍射(XRD)表征结果显示成功形成了铋纳米片,而电子显微镜表明,以溴氧化铋纳米棒为前驱体制备的BNS1尺寸在70-120纳米之间,以溴氧化铋纳米片为前驱体制备的BNS2尺寸在150-200 nm之间。值得注意的是,在环境温度下,在0.1M Na2SO4水溶液中,在-0.6 VvsRHE时,BNS2的氨产率和法拉第效率分别为3.99 μ gNH3 mgBi-1 h-1和7.04%,而 BNS1 则分别为 2.52 μ gNH3 mgBi-1 h-1 和 4.93%。在第二个工作中,我们采用光沉积策略制备了沉积在氯氧化铋纳米片上的铂单原子催化剂(PtxBOC SAC,该催化剂在苯乙炔的反马氏硅氢化加成反应中表现出优异的催化性能。我们首先合成了氯化氧铋纳米片,然后通过光沉积方法沉积了铂单原子。透射电子显微镜、X射线衍射、X射线光电子能谱、能量色散X射线光谱和CO吸收红外光谱结果表明,铂以单原子的形式均匀分布在氯氧化铋纳米片上。电感耦合等离子体质谱结果表明,铂单原子催化剂的铂负载量在0.5 wt%-4.0 wt%范围内。其中,Pt1BOC在苯乙炔的反马氏氢化硅烷化反应中表现出最高的催化性能,转化频率为156 min-1。该值远高于铂纳米颗粒对比样,也高于文献报道的值。此外,该催化剂表现出优异的稳定性,在5个循环后催化性能没有明显衰减。

关键词：卤氧化铋氮还原反应光沉积单原子催化剂反马尔可夫尼科夫氢硅化化反应

Metamaterial-Based Compact Antenna with Defected Ground Structure for 5G and Beyond

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第5期71卷 2383-2399页

作者： Md.Mushfiqur Rahman Md.Shabiul Islam Mohammad Tariqul Islam samir salem.al-bawri Wong Hin Yong Faculty of Engineering Multimedia UniversityPersiaran MultimediaCyberjaya63100SelangorMalaysia Department of Electrical Electronic and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangi43600Malaysia Space Science Centre Climate Change InstituteUniversiti Kebangsaan Malaysia(UKM)Bangi43600Malaysia

In this paper,a unit cell of a single-negative metamaterial structure loaded with a meander line and defected ground structure(DGS)is investigated as the principle radiating element of an *** unit cell antenna causes even or odd mode resonances similar to the unit cell structure depending on the orientation of the microstrip feed used to excite the unit ***,the orientation which gives low-frequency resonance is considered *** unit cell antenna is then loaded with a meander line which is parallel to the split bearing side and connects the other two sides orthogonal to the split bearing *** modified structure excites another mode of resonance at high frequency when a meander line defect is loaded on the metallic ground *** parameters of the meander line structure,the DGS shape,and the unit cell are optimized to place these two resonances at different frequencies with proper frequency intervals to enhance the ***,the feed is placed in an offset position for better impedance matching without affecting the bandwidth The compact dimension of the antenna is 0.25λL×0.23λL×0.02λL,whereλL is the free space wavelength with respect to the center frequency of the impedance *** proposed antenna is fabricated and *** results reveal that the modified design gives monopole like radiation patterns which achieves a fractional operating bandwidth of 26.6%,from 3.26 to 4.26 GHz for|S11|al plane.

关键词： Split ring resonator(SRR) meander line defected ground structure compact antenna bandwidth enhancement 5G technology

Super Compact UWB Monopole Antenna for Small IoT Devices

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第11期73卷 2785-2799页

作者： Ahmed Jamal Abdullah al-Gburi Zahriladha Zakaria Merih Palandoken Imran Mohd Ibrahim A.A.althuwayb Sarosh Ahmad samir salem.al-bawri Department of Electronics and Computer Engineering(FKEKK) Center for Telecommunication Research and Innovation(CeTRI)Universiti Teknikal Malaysia Melaka(UTeM)Durian Tungal76100Malaysia Department of Electrical and Electronics Engineering Izmir Katip Celebi UniversityIzmir35620Turkey Electrical Engineering Department Jouf UniversitySakaka72388AljoufKingdom of Saudi Arabia Universidad Carloa III de Madrid Leganes28911MadridSpain Space Science Centre Climate Change InstituteUniversiti Kebangsaan Malaysia(UKM)Bangi43600Malaysia

This article introduces a novel,ultrawideband(UWB)planar monopole antenna printed on Roger RT/5880 substrate in a compact size for small Internet of Things(IoT)*** total electrical dimensions of the proposed compact UWB antenna are 0.19λo×0.215λo×0.0196λo with the overall physical sizes of 15 mm×17 mm×1.548 mm at the lower resonance frequency of 3.8 *** planar monopole antenna is fed through the linearly tapered microstrip line on a partially structured ground plane to achieve optimum impedance matching for UWB *** proposed compact UWB antenna has an operation bandwidth of 9.53 GHz from 3.026 GHz up to 12.556 GHz at−10 dB return loss with a fractional bandwidth(FBW)of about 122%.The numerically computed and experimentally measured results agree well in between.A detailed time-domain analysis is additionally accomplished to verify the radiation efficiency of the proposed antenna design for the ultra-wideband signal *** fabricated prototype of a compact UWB antenna exhibits an omnidirectional radiation pattern with the low peak measured gain required of 2.55 dBi at 10 GHz and promising radiation efficiency of 90%.The proposed compact planar antenna has technical potential to be utilized in UWB and IoT applications.

关键词： Internet of things(IoT) ultra-wideband(UWB)application compact UWB monopole antenna

Machine learning based models for predicting compressive strength of geopolymer concrete

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第7期18卷 1028-1049页

作者： Quang-Huy LE Duy-Hung NGUYEN Thanh SANG-TO samir KHATIR Hoang LE-MINH Amir H.GANDOMI Thanh CUONG-LE Center for Engineering Application and Technology Solutions Ho Chi Minh City Open UniversityHo Chi Minh 700000Vietnam Institute of Civil Engineering Ho Chi Minh City University of TransportHo Chi Minh 700000Vietnam Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia

Recently,great attention has been paid to geopolymer concrete due to its advantageous mechanical and environmentally friendly *** effort has been made in experimental studies to advance the understanding of geopolymer concrete,in which compressive strength is one of the most important *** facilitate engineering work on the material,an efficient predicting model is *** this study,three machine learning(ML)-based models,namely deep neural network(DNN),K-nearest neighbors(KNN),and support vector machines(SVM),are developed for forecasting the compressive strength of the geopolymer concrete.A total of 375 experimental samples are collected from the literature to build a database for the development of the predicting models.A careful procedure for data preprocessing is implemented,by which outliers are examined and removed from the database and input variables are standardized before feeding to the fitting *** standard K-fold cross-validation approach is applied for evaluating the performance of the models so that overfitting status is well managed,thus the generalizability of the models is *** effectiveness of the models is assessed via statistical metrics including root mean squared error(RMSE),mean absolute error(MAE),correlation coefficient(R),and the recently proposed performance index(PI).The basic mean square error(MSE)is used as the loss function to be minimized during the model fitting *** three ML-based models are successfully developed for estimating the compressive strength,for which good correlations between the predicted and the true values are obtained for DNN,KNN,and *** numerical results suggest that the DNN model generally outperforms the other two models.

关键词： geopolymer concrete compressive strength prediction machine-learning based model deep neural network K-nearest neighbor support vector machines

Decagonal C-Shaped CSRR Textile-Based Metamaterial for Microwave Applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第4期71卷 1677-1693页

作者： Kabir Hossain Thennarasan Sabapathy Muzammil Jusoh Ping Jack Soh samir salem.al-bawri Mohamed Nasrun Osman Hasliza A.Rahim Danai Torrungrueng Prayoot Akkaraekthalin Advanced Communication Engineering(ACE)Centre of Excellence Universiti Malaysia Perlis(UniMAP)Jalan TigaPengkalan Jaya Business CentreKangar01000Malaysia Faculty of Electronic Engineering Technology Universiti Malaysia Perlis(UniMAP)Kampus Alam UniMAP Pauh PutraArau02600Malaysia Centre for Wireless Communications(CWC) University of Oulu90014Finland Space Science Centre Climate Change InstituteUniversiti Kebangsaan MalaysiaBangi43600Malaysia Department of Teacher Training in Electrical Engineering Faculty of Technical EducationKing Mongkut’s University of Technology North Bangkok(KMUTNB)WongsawangBangsue10800Thailand Department of Electrical and Computer Engineering Faculty of EngineeringKing Mongkut’s University of Technology North Bangkok(KMUTNB)WongsawangBangsue10800Thailand

This paper introduces a decagonal C-shaped complementary splitring resonator(CSRR)textile-based metamaterial(MTM).The overall size of the proposed sub-wavelength MTM unit cell is 0.28λ0×0.255λ0 at 3 *** stopband behaviour was first studied prior analysing the negative index properties of the proposed *** is worth noting that in this work a unique way the experiments were *** both simulations and measurements,the proposed MTM exhibited negative-permittivity and negative-refractive index characteristics with an average bandwidth of more than 3 GHz(considering 1.7 to 8.2 GHz as the measurements were carried out within this range).In simulations,the MTM exhibited negative-permittivity properties within the range of 1.7 to 7.52 GHz and 7.96 to 8.2 GHz;and negative-refractive index from 1.7 to 2.23 GHz and 2.33 to 5.09 GHz and 5.63 to 7.45 *** measured from 1.7 to 8.2 GHz,negative-permittivity and negative-refractive index characteristics are exhibited throughout an average bandwidth of more than 3 ***,the transmission coefficient attained in simulations and measurements indicated about 3 GHz of bandwidth,from 1.7 to 3.88 GHz and from 6.68 to 7.4 *** satisfactory agreement between simulations and experiments indicates the potential of the proposed MTM for microwave applications.

关键词： Metamaterial textile metamaterial bioelectromagnetics metasurface antennas