Several parameters of a commercial Si-based Schottky barrier diode (SBD) with unknown metal material and semiconductor-type have been investigated in this work from dark forward and reverse I-V characteristics in the ...Several parameters of a commercial Si-based Schottky barrier diode (SBD) with unknown metal material and semiconductor-type have been investigated in this work from dark forward and reverse I-V characteristics in the temperature (T) range of [274.5 K - 366.5 K]. Those parameters include the reverse saturation current (I<sub>s</sub>), the ideality factor (n), the series and the shunt resistances (R<sub>s</sub> and R<sub>sh</sub>), the effective and the zero bias barrier heights (Φ<sub>B</sub> and Φ<sub>B0</sub>), the product of the electrical active area (A) and the effective Richardson constant (A**), the built-in potential (V<sub>bi</sub>), together with the semiconductor doping concentration (N<sub>A</sub> or N<sub>D</sub>). Some of them have been extracted by using two or three different methods. The main features of each approach have been clearly stated. From one parameter to another, results have been discussed in terms of structure performance, comparison on one another when extracted from different methods, accordance or discordance with data from other works, and parameter’s temperature or voltage dependence. A comparison of results on Φ<sub>B</sub>, ΦB0</sub>, n and N<sub>A</sub> or N<sub>D</sub> parameters with some available data in literature for the same parameters, has especially led to clear propositions on the identity of the analyzed SBD’s metal and semiconductor-type.展开更多
In this work,forward current voltage characteristics for multi-quantum wells Al_(0.33)Ga_(0.67)As Schottky diode were measured at temperature ranges from 100 to 300 K.The main parameters of this Schottky diode,such as...In this work,forward current voltage characteristics for multi-quantum wells Al_(0.33)Ga_(0.67)As Schottky diode were measured at temperature ranges from 100 to 300 K.The main parameters of this Schottky diode,such as the ideality factor,barrier height,series resistance and saturation current,have been extracted using both analytical and heuristics methods.Differential evolution(DE),particle swarm optimization(PSO)and artificial bee colony(ABC)have been chosen as candidate heuristics algorithms,while Cheung technic was selected as analytical extraction method.The obtained results show clearly the high performance of DE algorithms in terms of parameters accuracy,convergence speed and robustness.展开更多
Extraction of accurate Photo Voltaic (PV) model parameters is a challenging task for PV simulator developers. To mitigate this challenging task a novel approach using Gravitational Search Algorithm (GSA) for accurate ...Extraction of accurate Photo Voltaic (PV) model parameters is a challenging task for PV simulator developers. To mitigate this challenging task a novel approach using Gravitational Search Algorithm (GSA) for accurate extraction of PV model parameters is proposed in this paper. GSA is a population based heuristic optimization method which depends on the law of gravity and mass interactions. In this optimization method, the searcher agents are collection of masses which interact with each other using laws of gravity and motion of Newton. The developed PV model utilizes mathematical equations and is described through an equivalent circuit model comprising of a current source, a diode, a series resistor and a shunt resistor including the effect of changes in solar irradiation and ambient temperature. The optimal values of photo-current, diode ideality factor, series resistance and shunt resistance of the developed PV model are obtained by using GSA. The simulations of the characteristic curves of PV modules (SM55, ST36 and ST40) are carried out using MATLAB/Simulink environment. Results obtained using GSA are compared with Differential Evolution (DE), which shows that GSA based parameters are better optimal when compared to DE.展开更多
This paper proposes a design and fine-tuning method for mixed electric and magnetic coupling filters.It derives the quantitative relationship between the coupling coefficients(electric and magnetic coupling,i.e.,EC an...This paper proposes a design and fine-tuning method for mixed electric and magnetic coupling filters.It derives the quantitative relationship between the coupling coefficients(electric and magnetic coupling,i.e.,EC and MC)and the linear coefficients of frequencydependent coupling for the first time.Different from the parameter extraction technique using the bandpass circuit model,the proposed approach explicitly relatesEC and MC to the coupling matrix model.This paper provides a general theoretic framework for computer-aided design and tuning of a mixed electric and magnetic coupling filter based on coupling matrices.An example of a 7th-order coaxial combline filter design is given in the paper,verifying the practical value of the approach.展开更多
An accurate and novel small-signal equivalent circuit model for GaN high-electron-mobility transistors(HEMTs)is proposed,which considers a dual-field-plate(FP)made up of a gate-FP and a source-FP.The equivalent circui...An accurate and novel small-signal equivalent circuit model for GaN high-electron-mobility transistors(HEMTs)is proposed,which considers a dual-field-plate(FP)made up of a gate-FP and a source-FP.The equivalent circuit of the overall model is composed of parasitic elements,intrinsic transistors,gate-FP,and source-FP networks.The equivalent circuit of the gate-FP is identical to that of the intrinsic transistor.In order to simplify the complexity of the model,a series combination of a resistor and a capacitor is employed to represent the source-FP.The analytical extraction procedure of the model parameters is presented based on the proposed equivalent circuit.The verification is carried out on a 4×250μm GaN HEMT device with a gate-FP and a source-FP in a 0.45μm technology.Compared with the classic model,the proposed novel small-signal model shows closer agreement with measured S-parameters in the range of 1.0 to 18.0 GHz.展开更多
This paper presents an accurate small-signal model for multi-gate GaAs pHEMTs in switching-mode.The extraction method for the proposed model is developed.A 2-gate switch structure is fabricated on a commercial 0.5μm ...This paper presents an accurate small-signal model for multi-gate GaAs pHEMTs in switching-mode.The extraction method for the proposed model is developed.A 2-gate switch structure is fabricated on a commercial 0.5μm AlGaAs/GaAs pHEMT technology to verify the proposed model.Excellent agreement has been obtained between the measured and simulated results over a wide frequency range.展开更多
A novel and accurate method is proposed to extract the intrinsic elements of the GaN high-electron-mobility transistor(HEMT) switch.The new extraction method is verified by comparing the simulated S-parameters with th...A novel and accurate method is proposed to extract the intrinsic elements of the GaN high-electron-mobility transistor(HEMT) switch.The new extraction method is verified by comparing the simulated S-parameters with the measured data over the 5-40 GHz frequency range.The percentage errors E_(ij) within 3.83% show the great agreement between the simulated S-parameters and the measured data.展开更多
Particle swarm optimization(PSO) and invasive weed optimization(IWO) algorithms are used for extracting the modeling parameters of materials useful for optics and photonics research community. These two bio-inspired a...Particle swarm optimization(PSO) and invasive weed optimization(IWO) algorithms are used for extracting the modeling parameters of materials useful for optics and photonics research community. These two bio-inspired algorithms are used here for the first time in this particular field to the best of our knowledge. The algorithms are used for modeling graphene oxide and the performances of the two are compared. Two objective functions are used for different boundary values. Root mean square(RMS) deviation is determined and compared.展开更多
The mathematical modeling of solar cells is essential for any optimization operation of the efficiency or the diagnosis of photovoltaic generator. The photovoltaic module is generally represented by an equivalent circ...The mathematical modeling of solar cells is essential for any optimization operation of the efficiency or the diagnosis of photovoltaic generator. The photovoltaic module is generally represented by an equivalent circuit whose parameters are experimentally calculated by using the characteristic current-tension, I-V. The precise determination of these parameters stays a challenge for the researchers, making to a big difference in the models and the digital methods dedicated to their characterizations. In the present paper, We are interested to characterize the parameters of single diode and two diodes models, in order to plan the behavior of the photovoltaic generator under real functioning conditions. We developed an identification method of the parameters using Newton Raphson method by using the software Matlab/Simulink. This method is the faster technique which allows the identification of several parameters and can be used in real time applications. The results of the proposed method show an accordance with the experimental and simulated characteristics of photovoltaic generator.展开更多
An improved parasitic parameter extraction method for InP high electron mobil-ity transistor(HEMT)is presented.Parasitic parameter extraction is the first step of model parameter extraction and its accuracy has a grea...An improved parasitic parameter extraction method for InP high electron mobil-ity transistor(HEMT)is presented.Parasitic parameter extraction is the first step of model parameter extraction and its accuracy has a great impact on the subsequent internal pa-rameter extraction.It is necessary to accurately determine and effectively eliminate the parasitic effect,so as to avoid the error propagation to the internal circuit parameters.In this paper,in order to obtain higher accuracy of parasitic parameters,parasitic parameters are extracted based on traditional analytical method and optimization algorithm to obtain the best parasitic parameters.The validity of the proposed parasitic parameter extraction method is verified with excellent agreement between the measured and modeled S-param-eters up to 40 GHz for InP HEMT.In 0.1-40 GHz InP HEMT,the average relative error of the optimization algorithm is about 9%higher than that of the analysis method,which verifies the validity of the parasitic parameter extraction method.The extraction of parasit-ic parameters not only provides a foundation for the high-precision extraction of small sig-nal intrinsic parameters of HEMT devices,but also lays a foundation for the high-preci-sion extraction of equivalent circuit model parameters of large signal and noise signals of HEMT devices.展开更多
Accurate PV system simulators are implemented with expensive software platforms using paid irradiance data.The main purpose of this paper is to develop and validate a PV system simulator,beginning with a solar cell pa...Accurate PV system simulators are implemented with expensive software platforms using paid irradiance data.The main purpose of this paper is to develop and validate a PV system simulator,beginning with a solar cell parameter extraction model,then test and validate long-termIrradiance data using free online source(Typical Meteorological Year TMY in(PVGIS)European website),and finally building full solar generator simulator to run in working real conditions.Comparing results with Accurate Paid PV simulators(which use theMuneer model)showed good accuracy of the proposed simulator.Work flow starts with the Irradiance model’s data processing,then solar cell 5 parameters model data processing(to extract cell parameters),and finally full system simulator.MATLAB coding programs in real working conditions are used for simulation.Results of solar cell parameter extraction show 99.6%to 99.99%matching with data sheet and cell performance under standard test conditions.Systemmodel simulation output shows 8%less yearly generated energy compared to the PVGIS 2022 long-term simulation(hourly basis(one-year time)).This is due to incident energy variations(between the years 2016 and 2022)of 4.02%.The novelty of the algorithm is the methodology,as it tests irradiance data on an hourly basis and validates results for a whole continuous year.Also,the 5-parameter solar cell model is used to be validated in long term analysis,not only STC conditions and could be applied on any PV solar cell.The algorithm and block diagramused are scalable,modular,and interchangeable with similarmodels to be tested.This simulator could test severalmethods andmodels in solar pv technology.展开更多
Electrical characterization analyses are proposed in this work using the Lambert function on Schottky junctions in GaN wide band gap semiconductor devices for extraction of physical parameters.The Lambert function is ...Electrical characterization analyses are proposed in this work using the Lambert function on Schottky junctions in GaN wide band gap semiconductor devices for extraction of physical parameters.The Lambert function is used to give an explicit expression of the current in the Schottky junction.This function is applied with defined conduction phenomena,whereas other work presented arbitrary(or undefined)conduction mechanisms in such parameters' extractions.Based upon AlGaN/GaN HEMT structures,extractions of parameters are undergone in order to provide physical characteristics.This work highlights a new expression of current with defined conduction phenomena in order to quantify the physical properties of Schottky contacts in AlGaN/GaN HEMT transistors.展开更多
We present a convenient and practical electromagnetic(EM)assisted small-signal model extraction method for InP double-heterojunction bipolar transistors(DHBTs).Parasitic parameters of pad and electrode fingers are ext...We present a convenient and practical electromagnetic(EM)assisted small-signal model extraction method for InP double-heterojunction bipolar transistors(DHBTs).Parasitic parameters of pad and electrode fingers are extracted by means of 3D EM simulation.The simulations with a new excitation scheme are closer to the actual on-wafer measurement conditions.Appropriate simulation settings are calibrated by comparing measurement and simulation of OPEN and SHORT structures.A simplerπ-type topology is proposed for the intrinsic model,in which the base-collector resistance Rμ,output resistance Rce are deleted,and a capacitance Cce is introduced to characterize the capacitive parasitic caused by the collector finger and emitter ground bar.The intrinsic parameters are all extracted by exact equations that are derived from rigorous mathematics.The method is characterized by its ease of implementation and the explicit physical meaning of extraction procedure.Experimental validations are performed at four biases for three InGaAs/InP HBT devices with 0.8×7μm,0.8×10μm and 0.8×15μm emitter,and quite good fitting results are obtained in the range of 0.1-50 GHz.展开更多
Microwave-assisted extraction(MAE)technology was used to extract silymarin from milk thistle seeds.The single factor experiments and quadratic orthogonal rotation regression combination design were adopted to study th...Microwave-assisted extraction(MAE)technology was used to extract silymarin from milk thistle seeds.The single factor experiments and quadratic orthogonal rotation regression combination design were adopted to study the effects of such factors as extraction time,extraction temperature,ethanol concentration and solid-liquid ratio on silymarin yield.Ultraviolet-Visible(UV-Vis)spectrophotometry method was employed to measure the silybin content.The optimal technological conditions for extracting silymarin from milk thistle seeds by MAE were determined,and then the extraction regression mathematical model was established.The importance orders of factors that influenced the extraction yield within the experimental model were as follows:ethanol concentration,the ratio of solid to liquid,extraction temperature and extraction time.The optimum extraction parameters were obtained as follows:extraction time 50 min,extraction temperature 130℃,ethanol concentration 85%(V/V),solid to liquid ratio 1∶40(g/mL),and under such conditions,experimental value of silymarin yield after being extracted three times is 59.33mg/g.The validation experiments verify that the established regression mathematical model can predict the extraction yield of silymarin accurately.展开更多
The measurement of banana pseudo-stem phenotypic parameters is a critical way to evaluate the growth status of bananas,and it can provide essential data support for mechanized cultivation operations such as fertilizat...The measurement of banana pseudo-stem phenotypic parameters is a critical way to evaluate the growth status of bananas,and it can provide essential data support for mechanized cultivation operations such as fertilization and pesticide application.Existing studies mainly measure the diameter of banana pseudo-stem as its phenotypic parameter.The banana pseudo-stem cross section was closer to an ellipse other than a standard circle,so the diameter parameter cannot adequately represent the phenotypic characteristics of the banana plant.In this study,an automatic measuring device for banana pseudo-stem phenotypic parameters was developed.The device,which integrates three different types of sensors:a laser ranging sensor,a rotary encoder,and a digital camera,were used to obtain the point cloud and image data of banana pseudo-stem.A K-means point clouds clustering algorithm based on Euclidean distance was proposed.The point cloud of banana pseudo-stem was identified and extracted.A three-dimensional reconstruction algorithm based on the ellipse model was also proposed.The three-dimensional contour of the pseudo-stem was calculated to obtain three types of phenotypic parameters:the long axis length,the short axis length,and the perimeter.Further,a synchronous trigger image acquisition mechanism was used to take pictures of pseudo-stems during measurement.It can be utilized for manual assessment of the growth status of the banana.Field experimental results showed that the three banana phenotypic parameters had a high correlation with the manual measurement results,and R^(2)is always more significant than 0.95,the total average measurement error and relative error were only 6.16 mm and 4.38%,respectively,both are within the acceptable agronomy range.In general,this method has good universality for plant stem detection,and the stem phenotypic parameters can be obtained by means of non-contact test,which is of great significance to the mechanized cultivation of the forest and fruit industry.展开更多
Blade-health monitoring is intensely required for turbomachinery because of the high failure risk of rotating blades.Blade-Tip Timing(BTT)is considered as the most promising technique for operational blade-vibration m...Blade-health monitoring is intensely required for turbomachinery because of the high failure risk of rotating blades.Blade-Tip Timing(BTT)is considered as the most promising technique for operational blade-vibration monitoring,which obtains the parameters that characterize the blade condition from recorded signals.However,its application is hindered by severe undersampling and stringent probe layouts.An inappropriate probe layout can make most of the existing methods invalid or inaccurate.Additionally,a general conflict arises between the allowed and required layouts because of arrangement restrictions.For the sake of economy and safety,parameter identification based on fewer probes has been preferred by users.In this work,a spatial-transformation-based method for parameter identification is proposed based on a single-probe BTT measurement.To present the general Sampling-Aliasing Frequency(SAFE)map definition,the traditional time-frequency analysis methods are extended to a time-sampling frequency.Then,a SAFE map is projected onto a parameter space using spatial transformation to extract the slope and intercept parameters,which can be physically interpreted as an engine order and a natural frequency using coordinate transformation.Finally,the effectiveness and robustness of the proposed method are verified by simulations and experiments under uniformly and nonuniformly variable speed conditions.展开更多
Extracting the unknown parameters of proton exchange membrane fuel cell(PEMFC)models accurately is vital to design,control,and simulate the actual PEMFC.In order to extract the unknown parameters of PEMFC models preci...Extracting the unknown parameters of proton exchange membrane fuel cell(PEMFC)models accurately is vital to design,control,and simulate the actual PEMFC.In order to extract the unknown parameters of PEMFC models precisely,this work presents an improved version of neural network algorithm(NNA),namely the multiple learning neural network algorithm(MLNNA).In MLNNA,six learning strategies are designed based on the created local elite archive and global elite archive to balance exploration and exploitation of MLNNA.To evaluate the performance of MLNNA,MLNNA is first employed to solve the well-known CEC 2015 test suite.Experimental results demonstrate that MLNNA outperforms NNA on most test functions.Then,MLNNA is used to extract the parameters of two PEMFC models including the BCS 500 W PEMFC model and the NedStack SP6 PEMFC model.Experimental results support the superiority of MLNNA in the parameter estimation of PEMFC models by comparing it with 10 powerful optimization algorithms.展开更多
A 10-bit 500 kHz low-power successive approximation register(SAR)analog-to-digital converter(ADC)for cryogenic infrared readout circuit is proposed.To improve the simulation accuracy of metal-oxidesemiconductor field-...A 10-bit 500 kHz low-power successive approximation register(SAR)analog-to-digital converter(ADC)for cryogenic infrared readout circuit is proposed.To improve the simulation accuracy of metal-oxidesemiconductor field-efect transistors(MOSFETs),corresponding modification in device model is presented on the basis of BSIM3v3 with parameter extraction at 77 K.Corresponding timing is adopted in comparator to eliminate the influence caused by abnormal performance of MOSFETs at 77 K.The SAR ADC is fabricated and verified by standard 0.35μm complementary metal oxide semiconductor(CMOS)process.At 77 K,measurement results show that signal to noise and distortion ratio(SNDR)is 54.74 dB and efective number of bits(ENOB)is 8.8 at the sampling rate of 500 kHz.The total circuit consumes 0.6 mW at 3.3 V power supply.展开更多
文摘Several parameters of a commercial Si-based Schottky barrier diode (SBD) with unknown metal material and semiconductor-type have been investigated in this work from dark forward and reverse I-V characteristics in the temperature (T) range of [274.5 K - 366.5 K]. Those parameters include the reverse saturation current (I<sub>s</sub>), the ideality factor (n), the series and the shunt resistances (R<sub>s</sub> and R<sub>sh</sub>), the effective and the zero bias barrier heights (Φ<sub>B</sub> and Φ<sub>B0</sub>), the product of the electrical active area (A) and the effective Richardson constant (A**), the built-in potential (V<sub>bi</sub>), together with the semiconductor doping concentration (N<sub>A</sub> or N<sub>D</sub>). Some of them have been extracted by using two or three different methods. The main features of each approach have been clearly stated. From one parameter to another, results have been discussed in terms of structure performance, comparison on one another when extracted from different methods, accordance or discordance with data from other works, and parameter’s temperature or voltage dependence. A comparison of results on Φ<sub>B</sub>, ΦB0</sub>, n and N<sub>A</sub> or N<sub>D</sub> parameters with some available data in literature for the same parameters, has especially led to clear propositions on the identity of the analyzed SBD’s metal and semiconductor-type.
文摘In this work,forward current voltage characteristics for multi-quantum wells Al_(0.33)Ga_(0.67)As Schottky diode were measured at temperature ranges from 100 to 300 K.The main parameters of this Schottky diode,such as the ideality factor,barrier height,series resistance and saturation current,have been extracted using both analytical and heuristics methods.Differential evolution(DE),particle swarm optimization(PSO)and artificial bee colony(ABC)have been chosen as candidate heuristics algorithms,while Cheung technic was selected as analytical extraction method.The obtained results show clearly the high performance of DE algorithms in terms of parameters accuracy,convergence speed and robustness.
文摘Extraction of accurate Photo Voltaic (PV) model parameters is a challenging task for PV simulator developers. To mitigate this challenging task a novel approach using Gravitational Search Algorithm (GSA) for accurate extraction of PV model parameters is proposed in this paper. GSA is a population based heuristic optimization method which depends on the law of gravity and mass interactions. In this optimization method, the searcher agents are collection of masses which interact with each other using laws of gravity and motion of Newton. The developed PV model utilizes mathematical equations and is described through an equivalent circuit model comprising of a current source, a diode, a series resistor and a shunt resistor including the effect of changes in solar irradiation and ambient temperature. The optimal values of photo-current, diode ideality factor, series resistance and shunt resistance of the developed PV model are obtained by using GSA. The simulations of the characteristic curves of PV modules (SM55, ST36 and ST40) are carried out using MATLAB/Simulink environment. Results obtained using GSA are compared with Differential Evolution (DE), which shows that GSA based parameters are better optimal when compared to DE.
基金supported by the National Natural Science Foundation of China under Grant No.62001339.
文摘This paper proposes a design and fine-tuning method for mixed electric and magnetic coupling filters.It derives the quantitative relationship between the coupling coefficients(electric and magnetic coupling,i.e.,EC and MC)and the linear coefficients of frequencydependent coupling for the first time.Different from the parameter extraction technique using the bandpass circuit model,the proposed approach explicitly relatesEC and MC to the coupling matrix model.This paper provides a general theoretic framework for computer-aided design and tuning of a mixed electric and magnetic coupling filter based on coupling matrices.An example of a 7th-order coaxial combline filter design is given in the paper,verifying the practical value of the approach.
文摘An accurate and novel small-signal equivalent circuit model for GaN high-electron-mobility transistors(HEMTs)is proposed,which considers a dual-field-plate(FP)made up of a gate-FP and a source-FP.The equivalent circuit of the overall model is composed of parasitic elements,intrinsic transistors,gate-FP,and source-FP networks.The equivalent circuit of the gate-FP is identical to that of the intrinsic transistor.In order to simplify the complexity of the model,a series combination of a resistor and a capacitor is employed to represent the source-FP.The analytical extraction procedure of the model parameters is presented based on the proposed equivalent circuit.The verification is carried out on a 4×250μm GaN HEMT device with a gate-FP and a source-FP in a 0.45μm technology.Compared with the classic model,the proposed novel small-signal model shows closer agreement with measured S-parameters in the range of 1.0 to 18.0 GHz.
文摘This paper presents an accurate small-signal model for multi-gate GaAs pHEMTs in switching-mode.The extraction method for the proposed model is developed.A 2-gate switch structure is fabricated on a commercial 0.5μm AlGaAs/GaAs pHEMT technology to verify the proposed model.Excellent agreement has been obtained between the measured and simulated results over a wide frequency range.
文摘A novel and accurate method is proposed to extract the intrinsic elements of the GaN high-electron-mobility transistor(HEMT) switch.The new extraction method is verified by comparing the simulated S-parameters with the measured data over the 5-40 GHz frequency range.The percentage errors E_(ij) within 3.83% show the great agreement between the simulated S-parameters and the measured data.
文摘Particle swarm optimization(PSO) and invasive weed optimization(IWO) algorithms are used for extracting the modeling parameters of materials useful for optics and photonics research community. These two bio-inspired algorithms are used here for the first time in this particular field to the best of our knowledge. The algorithms are used for modeling graphene oxide and the performances of the two are compared. Two objective functions are used for different boundary values. Root mean square(RMS) deviation is determined and compared.
文摘The mathematical modeling of solar cells is essential for any optimization operation of the efficiency or the diagnosis of photovoltaic generator. The photovoltaic module is generally represented by an equivalent circuit whose parameters are experimentally calculated by using the characteristic current-tension, I-V. The precise determination of these parameters stays a challenge for the researchers, making to a big difference in the models and the digital methods dedicated to their characterizations. In the present paper, We are interested to characterize the parameters of single diode and two diodes models, in order to plan the behavior of the photovoltaic generator under real functioning conditions. We developed an identification method of the parameters using Newton Raphson method by using the software Matlab/Simulink. This method is the faster technique which allows the identification of several parameters and can be used in real time applications. The results of the proposed method show an accordance with the experimental and simulated characteristics of photovoltaic generator.
文摘An improved parasitic parameter extraction method for InP high electron mobil-ity transistor(HEMT)is presented.Parasitic parameter extraction is the first step of model parameter extraction and its accuracy has a great impact on the subsequent internal pa-rameter extraction.It is necessary to accurately determine and effectively eliminate the parasitic effect,so as to avoid the error propagation to the internal circuit parameters.In this paper,in order to obtain higher accuracy of parasitic parameters,parasitic parameters are extracted based on traditional analytical method and optimization algorithm to obtain the best parasitic parameters.The validity of the proposed parasitic parameter extraction method is verified with excellent agreement between the measured and modeled S-param-eters up to 40 GHz for InP HEMT.In 0.1-40 GHz InP HEMT,the average relative error of the optimization algorithm is about 9%higher than that of the analysis method,which verifies the validity of the parasitic parameter extraction method.The extraction of parasit-ic parameters not only provides a foundation for the high-precision extraction of small sig-nal intrinsic parameters of HEMT devices,but also lays a foundation for the high-preci-sion extraction of equivalent circuit model parameters of large signal and noise signals of HEMT devices.
文摘Accurate PV system simulators are implemented with expensive software platforms using paid irradiance data.The main purpose of this paper is to develop and validate a PV system simulator,beginning with a solar cell parameter extraction model,then test and validate long-termIrradiance data using free online source(Typical Meteorological Year TMY in(PVGIS)European website),and finally building full solar generator simulator to run in working real conditions.Comparing results with Accurate Paid PV simulators(which use theMuneer model)showed good accuracy of the proposed simulator.Work flow starts with the Irradiance model’s data processing,then solar cell 5 parameters model data processing(to extract cell parameters),and finally full system simulator.MATLAB coding programs in real working conditions are used for simulation.Results of solar cell parameter extraction show 99.6%to 99.99%matching with data sheet and cell performance under standard test conditions.Systemmodel simulation output shows 8%less yearly generated energy compared to the PVGIS 2022 long-term simulation(hourly basis(one-year time)).This is due to incident energy variations(between the years 2016 and 2022)of 4.02%.The novelty of the algorithm is the methodology,as it tests irradiance data on an hourly basis and validates results for a whole continuous year.Also,the 5-parameter solar cell model is used to be validated in long term analysis,not only STC conditions and could be applied on any PV solar cell.The algorithm and block diagramused are scalable,modular,and interchangeable with similarmodels to be tested.This simulator could test severalmethods andmodels in solar pv technology.
基金Project supported by the French Department of Defense(DGA)
文摘Electrical characterization analyses are proposed in this work using the Lambert function on Schottky junctions in GaN wide band gap semiconductor devices for extraction of physical parameters.The Lambert function is used to give an explicit expression of the current in the Schottky junction.This function is applied with defined conduction phenomena,whereas other work presented arbitrary(or undefined)conduction mechanisms in such parameters' extractions.Based upon AlGaN/GaN HEMT structures,extractions of parameters are undergone in order to provide physical characteristics.This work highlights a new expression of current with defined conduction phenomena in order to quantify the physical properties of Schottky contacts in AlGaN/GaN HEMT transistors.
文摘We present a convenient and practical electromagnetic(EM)assisted small-signal model extraction method for InP double-heterojunction bipolar transistors(DHBTs).Parasitic parameters of pad and electrode fingers are extracted by means of 3D EM simulation.The simulations with a new excitation scheme are closer to the actual on-wafer measurement conditions.Appropriate simulation settings are calibrated by comparing measurement and simulation of OPEN and SHORT structures.A simplerπ-type topology is proposed for the intrinsic model,in which the base-collector resistance Rμ,output resistance Rce are deleted,and a capacitance Cce is introduced to characterize the capacitive parasitic caused by the collector finger and emitter ground bar.The intrinsic parameters are all extracted by exact equations that are derived from rigorous mathematics.The method is characterized by its ease of implementation and the explicit physical meaning of extraction procedure.Experimental validations are performed at four biases for three InGaAs/InP HBT devices with 0.8×7μm,0.8×10μm and 0.8×15μm emitter,and quite good fitting results are obtained in the range of 0.1-50 GHz.
文摘Microwave-assisted extraction(MAE)technology was used to extract silymarin from milk thistle seeds.The single factor experiments and quadratic orthogonal rotation regression combination design were adopted to study the effects of such factors as extraction time,extraction temperature,ethanol concentration and solid-liquid ratio on silymarin yield.Ultraviolet-Visible(UV-Vis)spectrophotometry method was employed to measure the silybin content.The optimal technological conditions for extracting silymarin from milk thistle seeds by MAE were determined,and then the extraction regression mathematical model was established.The importance orders of factors that influenced the extraction yield within the experimental model were as follows:ethanol concentration,the ratio of solid to liquid,extraction temperature and extraction time.The optimum extraction parameters were obtained as follows:extraction time 50 min,extraction temperature 130℃,ethanol concentration 85%(V/V),solid to liquid ratio 1∶40(g/mL),and under such conditions,experimental value of silymarin yield after being extracted three times is 59.33mg/g.The validation experiments verify that the established regression mathematical model can predict the extraction yield of silymarin accurately.
基金This work was financially supported by the Laboratory of Lingnan Modern Agriculture Project(Grant No.NT2021009)the National Key Research and Development Program of China(Grant No.2020YFD1000104)+2 种基金the China Agriculture Research System of MOF and MARA(Grant No.CARS-31-10)the Key-Areas Research and Development Program of Guangdong Province,China(Grant No.2019B020223002)the Department of Education Special Program of Guangdong Province,China(Grant No.2020KZDZX1036).
文摘The measurement of banana pseudo-stem phenotypic parameters is a critical way to evaluate the growth status of bananas,and it can provide essential data support for mechanized cultivation operations such as fertilization and pesticide application.Existing studies mainly measure the diameter of banana pseudo-stem as its phenotypic parameter.The banana pseudo-stem cross section was closer to an ellipse other than a standard circle,so the diameter parameter cannot adequately represent the phenotypic characteristics of the banana plant.In this study,an automatic measuring device for banana pseudo-stem phenotypic parameters was developed.The device,which integrates three different types of sensors:a laser ranging sensor,a rotary encoder,and a digital camera,were used to obtain the point cloud and image data of banana pseudo-stem.A K-means point clouds clustering algorithm based on Euclidean distance was proposed.The point cloud of banana pseudo-stem was identified and extracted.A three-dimensional reconstruction algorithm based on the ellipse model was also proposed.The three-dimensional contour of the pseudo-stem was calculated to obtain three types of phenotypic parameters:the long axis length,the short axis length,and the perimeter.Further,a synchronous trigger image acquisition mechanism was used to take pictures of pseudo-stems during measurement.It can be utilized for manual assessment of the growth status of the banana.Field experimental results showed that the three banana phenotypic parameters had a high correlation with the manual measurement results,and R^(2)is always more significant than 0.95,the total average measurement error and relative error were only 6.16 mm and 4.38%,respectively,both are within the acceptable agronomy range.In general,this method has good universality for plant stem detection,and the stem phenotypic parameters can be obtained by means of non-contact test,which is of great significance to the mechanized cultivation of the forest and fruit industry.
基金supported by the National Key Research and Development Program of China(No.2020YFB2010800)the National Natural Science Foundation of China(Nos.51875433 and 92060302)+1 种基金the Natural Science Foundation of Shaanxi Province,China(No.2019KJXX-043,2021JC-04)the Fundamental Research Funds for the Central Universities and the Foundation of Beilin District,China(No.GX2029)。
文摘Blade-health monitoring is intensely required for turbomachinery because of the high failure risk of rotating blades.Blade-Tip Timing(BTT)is considered as the most promising technique for operational blade-vibration monitoring,which obtains the parameters that characterize the blade condition from recorded signals.However,its application is hindered by severe undersampling and stringent probe layouts.An inappropriate probe layout can make most of the existing methods invalid or inaccurate.Additionally,a general conflict arises between the allowed and required layouts because of arrangement restrictions.For the sake of economy and safety,parameter identification based on fewer probes has been preferred by users.In this work,a spatial-transformation-based method for parameter identification is proposed based on a single-probe BTT measurement.To present the general Sampling-Aliasing Frequency(SAFE)map definition,the traditional time-frequency analysis methods are extended to a time-sampling frequency.Then,a SAFE map is projected onto a parameter space using spatial transformation to extract the slope and intercept parameters,which can be physically interpreted as an engine order and a natural frequency using coordinate transformation.Finally,the effectiveness and robustness of the proposed method are verified by simulations and experiments under uniformly and nonuniformly variable speed conditions.
基金This research was supported by the Postdoc Matching Fund Scheme(P0040875),the Hong Kong Polytechnic University.
文摘Extracting the unknown parameters of proton exchange membrane fuel cell(PEMFC)models accurately is vital to design,control,and simulate the actual PEMFC.In order to extract the unknown parameters of PEMFC models precisely,this work presents an improved version of neural network algorithm(NNA),namely the multiple learning neural network algorithm(MLNNA).In MLNNA,six learning strategies are designed based on the created local elite archive and global elite archive to balance exploration and exploitation of MLNNA.To evaluate the performance of MLNNA,MLNNA is first employed to solve the well-known CEC 2015 test suite.Experimental results demonstrate that MLNNA outperforms NNA on most test functions.Then,MLNNA is used to extract the parameters of two PEMFC models including the BCS 500 W PEMFC model and the NedStack SP6 PEMFC model.Experimental results support the superiority of MLNNA in the parameter estimation of PEMFC models by comparing it with 10 powerful optimization algorithms.
基金the National Major Scientific and Technological Special Project of China(No.2012ZX03004008)the Science and Technology Pillar Program of Tianjin(No.11ZCKFGX01400)
文摘A 10-bit 500 kHz low-power successive approximation register(SAR)analog-to-digital converter(ADC)for cryogenic infrared readout circuit is proposed.To improve the simulation accuracy of metal-oxidesemiconductor field-efect transistors(MOSFETs),corresponding modification in device model is presented on the basis of BSIM3v3 with parameter extraction at 77 K.Corresponding timing is adopted in comparator to eliminate the influence caused by abnormal performance of MOSFETs at 77 K.The SAR ADC is fabricated and verified by standard 0.35μm complementary metal oxide semiconductor(CMOS)process.At 77 K,measurement results show that signal to noise and distortion ratio(SNDR)is 54.74 dB and efective number of bits(ENOB)is 8.8 at the sampling rate of 500 kHz.The total circuit consumes 0.6 mW at 3.3 V power supply.