The effect of dysprosium and strontium on the total ionic conductivity of ceria in the system Ce1-xDyx-ySryO2-δ was studied. In this system, few compositions were prepared with x=0.15, y=0.015, 0.03 and 0.045 by modi...The effect of dysprosium and strontium on the total ionic conductivity of ceria in the system Ce1-xDyx-ySryO2-δ was studied. In this system, few compositions were prepared with x=0.15, y=0.015, 0.03 and 0.045 by modified sol-gel process using maltose and pectin as organic precursors. Rietveld refinement of XRD patterns confirms the cubic structure with space group Fm3m . SEM images show relatively uniform grains with clean and distinct grain boundaries. Four probe AC impedance measurements were carried out to evaluate the total ionic conductivity in the temperature range of 150-500 ℃ and frequency range of 40 Hz-1 MHz. The composition Ce0.85Dy0.12Sr0.03O2-δshows higher electrical conductivity than single-doped ceria samples.展开更多
Effect of multi-directional forging(MDF)on wear properties of Mg-Zn alloys(with 2,4,and 6wt%Zn)is investigated.Dry sliding wear test was performed using pin on disk machine on MDF processed and homogenized samples.Wea...Effect of multi-directional forging(MDF)on wear properties of Mg-Zn alloys(with 2,4,and 6wt%Zn)is investigated.Dry sliding wear test was performed using pin on disk machine on MDF processed and homogenized samples.Wear behavior of samples was analyzed at loads of ION and 20 N,with sliding distances of 2000m and 4000m,at a sliding velocity of 3m/s.Microstructures of worn samples were observed under scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and x-ray diffraction(XRD)and the results were analyzed.Mechanical properties were evaluated using microhardness test.After 5 passes of MDF,the average grain size was found to be 30±4p m,22±3 pm,and 18±3 pm,in Mg-2%Zn,Mg-4%Zn,and Mg-6%Zn alloys,respectively,with significant improvement in hardness in all cases.Wear resistance was improved after MDF processing,as well as,with increment in Zn content in Mg alloy.However,it decreased when the load and the sliding distance increased.Worn surface exhibited ploughing,delamination,plastic deformation,and wear debris along sliding direction,and abrasive wear was found to be the main mechanism.展开更多
Cel-xSmxO2 （x=0, 0.1, 0.2 and 0.3） and Sm-doped ceria＋（2%-8%）Al2O3 were synthesized through sol-gel process followed by low temperature combustion. The synthesis, structure, densification, conductivity and therma...Cel-xSmxO2 （x=0, 0.1, 0.2 and 0.3） and Sm-doped ceria＋（2%-8%）Al2O3 were synthesized through sol-gel process followed by low temperature combustion. The synthesis, structure, densification, conductivity and thermal expansion were studied, and the structure and phase were confirmed by XRD. Dense ceramics were obtained through sintering the pellets at 1300 ℃. 2% and 4% Al2O3 were added into Ce0.8Sm0.2O2 to promote the densification at 1250 ℃. The surface morphology of the sintered pellets was analyzed using SEM. A two-probe AC impedance spectroscopy was used to study the total ionic conductivity.展开更多
Exploring anode materials with high energy and power density is one of the critical milestones in developing sodium-ion batteries/capacitors(SIBs/SICs).Here,the Mo and W-based bimetallic organic framework(Mo-W-MOF)wit...Exploring anode materials with high energy and power density is one of the critical milestones in developing sodium-ion batteries/capacitors(SIBs/SICs).Here,the Mo and W-based bimetallic organic framework(Mo-W-MOF)with core-shell structure is first formed by a facile strategy,followed by a selenization and carbonization strategy to finally prepare multileveled Mo WSe_(2)/WO_(3)/C anode materials with core-shell petal like curled nanosheet structure.Between the petal(MoSe_(2))-core(WO_(3))structure,the formation of WSe_(2)flakes by partial selenization on the surface of WO_(3)serves as a heterogeneous connection between MoSe_(2)and WO_(3).The enlarged layer distance(0.677 nm)between MoSe_(2)and WSe_(2)can facilitate the rapid transfer of Na+and electrons.The density functional theory(DFT)calculations verify that the Mo WSe_(2)/WO_(3)/C heterostructure performs excellent metallic properties.Ex-situ X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and transmission electron microscopy(TEM)confirm the activation process from the initial insertion reaction to the later conversion reaction.Resultantly,when employed as the anode of SIBs,a remarkable capacity of 384.3 mA h g-1after 950 cycles at 10 A g^(-1)is performed.Furthermore,the SICs assembled with commercial activated carbon(AC)as the cathode exhibits a remarkable energy density of 81.86 W h kg^(-1)(at 190 W kg^(-1))and 72.83 W h kg^(-1)(at 3800 W kg^(-1)).The unique structural design and the reaction investigation of the electrode process can provide a reference for the development of transition metal chalcogenides anodes.展开更多
In this work,the stress intensity factors(SIFs)for a wide range of semi-elliptical surface cracks with different inclination angles in a cylindrical bar subjected to pure tension were investigated numerically.The main...In this work,the stress intensity factors(SIFs)for a wide range of semi-elliptical surface cracks with different inclination angles in a cylindrical bar subjected to pure tension were investigated numerically.The main parameters considered to evaluate the SIFs were the crack size ratio(a/d),the crack aspect ratio(a/c),and the crack inclination angle(0).The dual-boundary element met hod implemented in software BEASY was used to compute the SIF values for cracks.Furt her more,the general closed-form solutions were proposed to evaluate the corresponding SIFs for Mode I,Mode II and Mode III types of fracture through curve fitting approaches.These solutions can provide accurate and reliable values of stress intensity factors for a crack on a cylindrical bar under pure tension in a rapid way compared to those obtained using computational models.In addition,these results can be used as inputs for failure studies and life evaluations of cracked cylinder under working conditions.展开更多
In recent times,pattern recognition of communication modulation signals has gained significant attention in several application areas such as military,civilian field,etc.It becomes essential to design a safe and robus...In recent times,pattern recognition of communication modulation signals has gained significant attention in several application areas such as military,civilian field,etc.It becomes essential to design a safe and robust feature extraction(FE)approach to efficiently identify the various signal modulation types in a complex platform.Several works have derived new techniques to extract the feature parameters namely instant features,fractal features,and so on.In addition,machine learning(ML)and deep learning(DL)approaches can be commonly employed for modulation signal classification.In this view,this paper designs pattern recognition of communication signal modulation using fractal features with deep neural networks(CSM-FFDNN).The goal of the CSM-FFDNN model is to classify the different types of digitally modulated signals.The proposed CSM-FFDNN model involves two major processes namely FE and classification.The proposed model uses Sevcik Fractal Dimension(SFD)technique to extract the fractal features from the digital modulated signals.Besides,the extracted features are fed into the DNN model for modulation signal classification.To improve the classification performance of the DNN model,a barnacles mating optimizer(BMO)is used for the hyperparameter tuning of the DNN model in such a way that the DNN performance can be raised.A wide range of simulations takes place to highlight the enhanced performance of the CSM-FFDNN model.The experimental outcomes pointed out the superior recognition rate of the CSM-FFDNN model over the recent state of art methods interms of different evaluation parameters.展开更多
At 12.8 MHz center frequency,the advanced miniaturized polymer-based planar high quality factor(Q)passive elements embedded bandpassfilter works in the L-band.Because most of the demands operate inside the spectrum,the...At 12.8 MHz center frequency,the advanced miniaturized polymer-based planar high quality factor(Q)passive elements embedded bandpassfilter works in the L-band.Because most of the demands operate inside the spectrum,the wideband or high-speed operation necessary to enhance must be acquired in microwave frequency ranges.The channel has a quiet,high-performance micro-filter with wideband rejection.Capacitors and inductors are used in the high quality factor(Q)passive components,and related networks are incorporated in thefilter.Embedded layers are concatenated using Three-Dimensional Integrated Circuit(3D-IC)integration,parasitics are removed,and interconnection losses are negotiated using de-embedding methods.A wireless application-based Liquid Crystalline Polymer(LCP)viewpoint is employed as a substrate material in this work.The polymer processes,their properties,and the incorporated high-Q Band Pass Filter Framework.The suggestedfilter model is computed and manufactured utilizing the L-band frequency spectrum,decreasing total physical length by 31%while increasing bandwidth by 45%.展开更多
In the agriculture field,one of the recent research topics is recognition and classification of diseases from the leaf images of a plant.The recognition of agricultural plant diseases by utilizing the image processing...In the agriculture field,one of the recent research topics is recognition and classification of diseases from the leaf images of a plant.The recognition of agricultural plant diseases by utilizing the image processing techniques will minimize the reliance on the farmers to protect the agricultural products.In this paper,Recognition and Classification of Paddy Leaf Diseases using Optimized Deep Neural Network with Jaya Algorithm is proposed.For the image acquisition the images of rice plant leaves are directly captured from the farm field for normal,bacterial blight,brown spot,sheath rot and blast diseases.In pre-processing,for the background removal the RGB images are converted into HSV images and based on the hue and saturation parts binary images are extracted to split the diseased and non-diseased part.For the segmentation of diseased portion,normal portion and background a clustering method is used.Classification of diseases is carried out by using Optimized Deep Neural Network with Jaya Optimization Algorithm(DNN_JOA).In order to precise the stability of this approach a feedback loop is generated in the post processing step.The experimental results are evaluated and compared with ANN,DAE and DNN.The proposed method achieved high accuracy of 98.9%for the blast affected,95.78%for the bacterial blight,92%for the sheath rot,94%for the brown spot and 90.57%for the normal leaf image.展开更多
The main objective of implementing charging stations is to ensure the good charging to theElectric Vehicles by using a solar PV array which is interconnected to the battery energy storagesystems. The charging station ...The main objective of implementing charging stations is to ensure the good charging to theElectric Vehicles by using a solar PV array which is interconnected to the battery energy storagesystems. The charging station regulates the supply voltage and frequency without the use of amechanical speed governor. It also assures that energy gained from grid or by the DG set willhave the unity power factor (UPF) when the load is nonlinear. Besides this, the Point of CommonCoupling (PCC) voltage is synchronised with the grid/generator voltage in order to providecontinuous charging. In order to increase the optimal efficiency of the charging stations, thecharging stations will perform the active/reactive power transfer from the vehicle to grid, vehicleto house and vehicle to vehicle (V2V) power transfer. The operational experiment of the chargingstation is simulated and verified by using MATLAB/SIMULINK.展开更多
基金the UGC for providing financial assistance under DSKPDF, BSR project No. F.4-2/2006(BSR)/13-389/2010 (BSR)
文摘The effect of dysprosium and strontium on the total ionic conductivity of ceria in the system Ce1-xDyx-ySryO2-δ was studied. In this system, few compositions were prepared with x=0.15, y=0.015, 0.03 and 0.045 by modified sol-gel process using maltose and pectin as organic precursors. Rietveld refinement of XRD patterns confirms the cubic structure with space group Fm3m . SEM images show relatively uniform grains with clean and distinct grain boundaries. Four probe AC impedance measurements were carried out to evaluate the total ionic conductivity in the temperature range of 150-500 ℃ and frequency range of 40 Hz-1 MHz. The composition Ce0.85Dy0.12Sr0.03O2-δshows higher electrical conductivity than single-doped ceria samples.
文摘Effect of multi-directional forging(MDF)on wear properties of Mg-Zn alloys(with 2,4,and 6wt%Zn)is investigated.Dry sliding wear test was performed using pin on disk machine on MDF processed and homogenized samples.Wear behavior of samples was analyzed at loads of ION and 20 N,with sliding distances of 2000m and 4000m,at a sliding velocity of 3m/s.Microstructures of worn samples were observed under scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and x-ray diffraction(XRD)and the results were analyzed.Mechanical properties were evaluated using microhardness test.After 5 passes of MDF,the average grain size was found to be 30±4p m,22±3 pm,and 18±3 pm,in Mg-2%Zn,Mg-4%Zn,and Mg-6%Zn alloys,respectively,with significant improvement in hardness in all cases.Wear resistance was improved after MDF processing,as well as,with increment in Zn content in Mg alloy.However,it decreased when the load and the sliding distance increased.Worn surface exhibited ploughing,delamination,plastic deformation,and wear debris along sliding direction,and abrasive wear was found to be the main mechanism.
文摘Cel-xSmxO2 （x=0, 0.1, 0.2 and 0.3） and Sm-doped ceria＋（2%-8%）Al2O3 were synthesized through sol-gel process followed by low temperature combustion. The synthesis, structure, densification, conductivity and thermal expansion were studied, and the structure and phase were confirmed by XRD. Dense ceramics were obtained through sintering the pellets at 1300 ℃. 2% and 4% Al2O3 were added into Ce0.8Sm0.2O2 to promote the densification at 1250 ℃. The surface morphology of the sintered pellets was analyzed using SEM. A two-probe AC impedance spectroscopy was used to study the total ionic conductivity.
基金supported by the National Natural Science Foundation of China(22008053,52002111)the Key Research and Development Program of Hebei Province(20310601D,205A4401D)the Ministry of Higher Education of Malaysia for the Fundamental Research Grant(FRGS/1/2018/STG02/UM/02/10)awarded to Woo Haw Jiunn and University of Malaya research grant(GPF 038B-2018)。
文摘Exploring anode materials with high energy and power density is one of the critical milestones in developing sodium-ion batteries/capacitors(SIBs/SICs).Here,the Mo and W-based bimetallic organic framework(Mo-W-MOF)with core-shell structure is first formed by a facile strategy,followed by a selenization and carbonization strategy to finally prepare multileveled Mo WSe_(2)/WO_(3)/C anode materials with core-shell petal like curled nanosheet structure.Between the petal(MoSe_(2))-core(WO_(3))structure,the formation of WSe_(2)flakes by partial selenization on the surface of WO_(3)serves as a heterogeneous connection between MoSe_(2)and WO_(3).The enlarged layer distance(0.677 nm)between MoSe_(2)and WSe_(2)can facilitate the rapid transfer of Na+and electrons.The density functional theory(DFT)calculations verify that the Mo WSe_(2)/WO_(3)/C heterostructure performs excellent metallic properties.Ex-situ X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and transmission electron microscopy(TEM)confirm the activation process from the initial insertion reaction to the later conversion reaction.Resultantly,when employed as the anode of SIBs,a remarkable capacity of 384.3 mA h g-1after 950 cycles at 10 A g^(-1)is performed.Furthermore,the SICs assembled with commercial activated carbon(AC)as the cathode exhibits a remarkable energy density of 81.86 W h kg^(-1)(at 190 W kg^(-1))and 72.83 W h kg^(-1)(at 3800 W kg^(-1)).The unique structural design and the reaction investigation of the electrode process can provide a reference for the development of transition metal chalcogenides anodes.
文摘In this work,the stress intensity factors(SIFs)for a wide range of semi-elliptical surface cracks with different inclination angles in a cylindrical bar subjected to pure tension were investigated numerically.The main parameters considered to evaluate the SIFs were the crack size ratio(a/d),the crack aspect ratio(a/c),and the crack inclination angle(0).The dual-boundary element met hod implemented in software BEASY was used to compute the SIF values for cracks.Furt her more,the general closed-form solutions were proposed to evaluate the corresponding SIFs for Mode I,Mode II and Mode III types of fracture through curve fitting approaches.These solutions can provide accurate and reliable values of stress intensity factors for a crack on a cylindrical bar under pure tension in a rapid way compared to those obtained using computational models.In addition,these results can be used as inputs for failure studies and life evaluations of cracked cylinder under working conditions.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2021R1F1A1063319).
文摘In recent times,pattern recognition of communication modulation signals has gained significant attention in several application areas such as military,civilian field,etc.It becomes essential to design a safe and robust feature extraction(FE)approach to efficiently identify the various signal modulation types in a complex platform.Several works have derived new techniques to extract the feature parameters namely instant features,fractal features,and so on.In addition,machine learning(ML)and deep learning(DL)approaches can be commonly employed for modulation signal classification.In this view,this paper designs pattern recognition of communication signal modulation using fractal features with deep neural networks(CSM-FFDNN).The goal of the CSM-FFDNN model is to classify the different types of digitally modulated signals.The proposed CSM-FFDNN model involves two major processes namely FE and classification.The proposed model uses Sevcik Fractal Dimension(SFD)technique to extract the fractal features from the digital modulated signals.Besides,the extracted features are fed into the DNN model for modulation signal classification.To improve the classification performance of the DNN model,a barnacles mating optimizer(BMO)is used for the hyperparameter tuning of the DNN model in such a way that the DNN performance can be raised.A wide range of simulations takes place to highlight the enhanced performance of the CSM-FFDNN model.The experimental outcomes pointed out the superior recognition rate of the CSM-FFDNN model over the recent state of art methods interms of different evaluation parameters.
文摘At 12.8 MHz center frequency,the advanced miniaturized polymer-based planar high quality factor(Q)passive elements embedded bandpassfilter works in the L-band.Because most of the demands operate inside the spectrum,the wideband or high-speed operation necessary to enhance must be acquired in microwave frequency ranges.The channel has a quiet,high-performance micro-filter with wideband rejection.Capacitors and inductors are used in the high quality factor(Q)passive components,and related networks are incorporated in thefilter.Embedded layers are concatenated using Three-Dimensional Integrated Circuit(3D-IC)integration,parasitics are removed,and interconnection losses are negotiated using de-embedding methods.A wireless application-based Liquid Crystalline Polymer(LCP)viewpoint is employed as a substrate material in this work.The polymer processes,their properties,and the incorporated high-Q Band Pass Filter Framework.The suggestedfilter model is computed and manufactured utilizing the L-band frequency spectrum,decreasing total physical length by 31%while increasing bandwidth by 45%.
文摘In the agriculture field,one of the recent research topics is recognition and classification of diseases from the leaf images of a plant.The recognition of agricultural plant diseases by utilizing the image processing techniques will minimize the reliance on the farmers to protect the agricultural products.In this paper,Recognition and Classification of Paddy Leaf Diseases using Optimized Deep Neural Network with Jaya Algorithm is proposed.For the image acquisition the images of rice plant leaves are directly captured from the farm field for normal,bacterial blight,brown spot,sheath rot and blast diseases.In pre-processing,for the background removal the RGB images are converted into HSV images and based on the hue and saturation parts binary images are extracted to split the diseased and non-diseased part.For the segmentation of diseased portion,normal portion and background a clustering method is used.Classification of diseases is carried out by using Optimized Deep Neural Network with Jaya Optimization Algorithm(DNN_JOA).In order to precise the stability of this approach a feedback loop is generated in the post processing step.The experimental results are evaluated and compared with ANN,DAE and DNN.The proposed method achieved high accuracy of 98.9%for the blast affected,95.78%for the bacterial blight,92%for the sheath rot,94%for the brown spot and 90.57%for the normal leaf image.
文摘The main objective of implementing charging stations is to ensure the good charging to theElectric Vehicles by using a solar PV array which is interconnected to the battery energy storagesystems. The charging station regulates the supply voltage and frequency without the use of amechanical speed governor. It also assures that energy gained from grid or by the DG set willhave the unity power factor (UPF) when the load is nonlinear. Besides this, the Point of CommonCoupling (PCC) voltage is synchronised with the grid/generator voltage in order to providecontinuous charging. In order to increase the optimal efficiency of the charging stations, thecharging stations will perform the active/reactive power transfer from the vehicle to grid, vehicleto house and vehicle to vehicle (V2V) power transfer. The operational experiment of the chargingstation is simulated and verified by using MATLAB/SIMULINK.
