This paper proposes an improved version of the Partial Reinforcement Optimizer(PRO),termed LNPRO.The LNPRO has undergone a learner phase,which allows for further communication of information among the PRO population,c...This paper proposes an improved version of the Partial Reinforcement Optimizer(PRO),termed LNPRO.The LNPRO has undergone a learner phase,which allows for further communication of information among the PRO population,changing the state of the PRO in terms of self-strengthening.Furthermore,the Nelder-Mead simplex is used to optimize the best agent in the population,accelerating the convergence speed and improving the accuracy of the PRO population.By comparing LNPRO with nine advanced algorithms in the IEEE CEC 2022 benchmark function,the convergence accuracy of the LNPRO has been verified.The accuracy and stability of simulated data and real data in the parameter extraction of PV systems are crucial.Compared to the PRO,the precision and stability of LNPRO have indeed been enhanced in four types of photovoltaic components,and it is also superior to other excellent algorithms.To further verify the parameter extraction problem of LNPRO in complex environments,LNPRO has been applied to three types of manufacturer data,demonstrating excellent results under varying irradiation and temperatures.In summary,LNPRO holds immense potential in solving the parameter extraction problems in PV systems.展开更多
We improve the genetic algorithm by combining it with a simulated annealing algorithm. The improved algorithm is used to extract model parameters of SOI MOSFETs, which are fabricated with standard 1.2μm CMOS/SOI tech...We improve the genetic algorithm by combining it with a simulated annealing algorithm. The improved algorithm is used to extract model parameters of SOI MOSFETs, which are fabricated with standard 1.2μm CMOS/SOI technology developed by the Institute of Microelectronics of the Chinese Academy of Sciences. The simulation results using this model are in excellent agreement with experimental results. The precision is improved noticeably compared to commercial software. This method requires neither a deeper understanding of SOl MOSFETs model nor more complex computations than conventional algorithms used by commercial software. Comprehensive verification shows that this model is applicable to a very large range of device sizes.展开更多
A novel parameter extraction technique suitable f or short channel length lightly-doped-drain (LDD) MOSFET's is proposed which seg ments the total gate bias range,and executes the linear regression in every subs ...A novel parameter extraction technique suitable f or short channel length lightly-doped-drain (LDD) MOSFET's is proposed which seg ments the total gate bias range,and executes the linear regression in every subs ections,yielding the gate bias dependent parameters,such as effective channel le ngth,parasitic resistance,and mobility,etc.This method avoids the gate bias rang e optimization,and retains the accuracy and simplicity of linear regression.The extracted gate bias dependent parameters are implemented in the compact I-V model which has been proposed for deep submicron LDD MOSFET's.The good agreemen ts between simulations and measurements of the devices on 0.18μm CMOS technolo gy indicate the effectivity of this technique.展开更多
Previous studies have often focused on monitoring grassland growth as the primary target of remote sensing investigations on grassland ecological restoration in the northern Tibetan Plateau,overlooking the crucial rol...Previous studies have often focused on monitoring grassland growth as the primary target of remote sensing investigations on grassland ecological restoration in the northern Tibetan Plateau,overlooking the crucial role played by gravel in the ecological restoration of these grasslands.This study utilizes supervised classification and segmentation techniques based on machine learning to extract gravel morphology profiles from field-sampled plot images and calculate their characteristic parameters.Employing a multivariate linear approach combined with Principal Component Analysis(PCA),a model for inferring gravel characteristic parameters is constructed.Statistical features,particle size characteristics,and spatial distribution patterns of gravel are analyzed.Results reveal that gravel predominantly exhibit sub-rounded shapes,with 80%classified as fine gravel.The coefficients of determination(R2)between gravel particle size and coverage,perimeter,and area are 0.444,0.724,and 0.557,respectively,indicating linear relationships.The cumulative contribution rate of the top five remote sensing factors is 95.44%,with the first geological factor contributing 77.64%,collectively reflecting the primary information of the 20 factors used.Modeling shows that areas with larger gravel particle sizes correspond to increased perimeter and coverage.Gravels in the Nagqu Prefecture of northern Xizang have a particle size range of 4-8 mm,primarily comprising fine gravel which accounts for 94.61%.These findings provide a scientific basis for extracting gravel characteristic parameters and understanding their spatial distribution variations in the northern Tibetan Plateau.展开更多
A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experiment...A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experimental data. The extraction strategy is straightforward and can be easily implemented as a CAD tool to model spiral inductors. The resulting circuit models will be very useful for RF circuit designers.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 sub circuit model for VDMOS is built according to its physical structure.Parameters and formulas describing the device are also derived from this model.Comparing to former results,this model avoids too many technic...A sub circuit model for VDMOS is built according to its physical structure.Parameters and formulas describing the device are also derived from this model.Comparing to former results,this model avoids too many technical parameters and simplify the sub circuit efficiently.As a result of numeric computation,this simple model with clear physical conception demonstrates excellent agreements between measured and modeled response (DC error within 5%,AC error within 10%).Such a model is now available for circuit simulation and parameter extraction.展开更多
Parameter extraction is an important step for circuit simulation methods that are based on physical models of semiconductor devices. A novel physical parameter extraction approach for Schottky diodes is proposed in th...Parameter extraction is an important step for circuit simulation methods that are based on physical models of semiconductor devices. A novel physical parameter extraction approach for Schottky diodes is proposed in this paper. By employing a set of analytical formulas, this approach extracts all of the necessary physical parameters of the diode chip in a unique way. It then extracts the package parasitic parameters with a curve-fitting method. To validate the proposed approach, a model HSMS-282 c commercial Schottky diode is taken as an example. Its physical parameters are extracted and used to simulate the diode＇s electrical characteristics. The simulated results based on the extracted parameters are compared with the measurements and a good agreement is obtained, which verifies the feasibility and accuracy of the proposed approach.展开更多
Current transport mechanism in Ni-germanide/n-type Ge Schottky diodes is investigated using current-voltage characterisation technique with annealing temperatures from 300 ℃ to 500℃. Based on the current transport m...Current transport mechanism in Ni-germanide/n-type Ge Schottky diodes is investigated using current-voltage characterisation technique with annealing temperatures from 300 ℃ to 500℃. Based on the current transport model, a simple method to extract parameters of the NiGe/Ge diode is presented by using the I-V characteristics. Parameters of NiGe/n-type Ge Schottky diodes fabricated for testing in this paper are as follows： the ideality factor n, the series resistance Rs, the zero-field barrier height Фb0, the interface state density Dit, and the interracial layer capacitance Ci. It is found that the ideality factor n of the diode increases with the increase of annealing temperature. As the temperature increases, the interface defects from the sputtering damage and the penetration of metallic states into the Ge energy gap are passivated, thus improving the junction quality. However, the undesirable crystallisations of Ni-germanide are observed together with NiGe at a temperature higher than 400℃. Depositing a very thin （-1 nm） heavily Ge-doped n＋ Ge intermediate layer can improve the NiGe film morphology significantly.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
A phase-derived velocity measurement method is proposed in a wideband coherent system,based on a precise echo model considering the inner pulse Doppler effect caused by fast moving targets.The Cramer-Rao low band of v...A phase-derived velocity measurement method is proposed in a wideband coherent system,based on a precise echo model considering the inner pulse Doppler effect caused by fast moving targets.The Cramer-Rao low band of velocity measurement precision is deduced,demonstrating the high precision of the proposed method.Simulations and out-field experiments further validate the effectiveness of the proposed method in high-precision measurement and micro-motion extraction for targets with weak reflection intensity.Compared with the long-time integration approaches for velocity measurement,the phase-derived method is easy to implement and meets the requirement for high data rate,which makes it suitable for micro-motion feature extraction in wideband systems.展开更多
This paper describes a method to extract electrical parameters of the through via in Package-on-Package(PoP)with interposer.Using the de-embedding technique electrical parameters of the through via are extracted.With ...This paper describes a method to extract electrical parameters of the through via in Package-on-Package(PoP)with interposer.Using the de-embedding technique electrical parameters of the through via are extracted.With the extracted electrical parameters of the through via,the effects of via height,the distance between signal and GND vias,and anti-pad clearance on the electrical characteristics are discussed.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
The method extracting the electromagnetic parameters from scattering coefficients was studied in this paper. The Support Vector Machine (SVM) method is used to solve the inverse problem of parameters extraction. The m...The method extracting the electromagnetic parameters from scattering coefficients was studied in this paper. The Support Vector Machine (SVM) method is used to solve the inverse problem of parameters extraction. The mapping relationship is set up by calculating a large number of S pa-rameters from the samples with different permittivity by using transmission line theory. The simulated data set is used as training data set for SVM. After the training, the SVM is used to predict the permittivity of material from the scattering coefficients.展开更多
An accurate and broad-band method for hetero-junction bipolar transistors(HBT)small-signal model parameters-extraction is presented in this paper.An equivalent circuit forthe HBT under a forward-bias condition is prop...An accurate and broad-band method for hetero-junction bipolar transistors(HBT)small-signal model parameters-extraction is presented in this paper.An equivalent circuit forthe HBT under a forward-bias condition is proposed for extraction of accessresistance and parasiticinductance.This method differs from previous ones by extracting the c-quivalent circuit parameterswithout using special test structure or global numerical optimization techniques.The mainadvantage of this method is that a unique and physically meaningful set of intrinsic parameters isextracted from impedance and admittance representation of the measured S-pa-rameters in thefrequency range of 1-12 GHz under different bias conditions.The method yields a deviation of lessthan 5%between measured and modeled S-parameters.展开更多
Indonesian oil sands were systematically separated to investigate their basic composition.The extraction effects of the solvents with different Hilderbrand solubility parameters(HSPs)on the bitumen of Indonesian oil s...Indonesian oil sands were systematically separated to investigate their basic composition.The extraction effects of the solvents with different Hilderbrand solubility parameters(HSPs)on the bitumen of Indonesian oil sands were compared.Furthermore,the Hansen solubility combination parameter(HSCP)and Teas triangle were used to explore rules in the separation of oil sands bitumen via solvent extraction.Finally,the saturates,aromatics,resins,and asphaltenes(SARA)fractions of the bitumen from Indonesian oil sands were analyzed.The results showed that the Indonesian oil sands were oil-wet with a bitumen content of 24.93%.The solvent extraction for bitumen could be accurately and conveniently selected based on the solubility parameter.When the HSPs of the extraction solvent were around 18–19 and the HSCPs were closer to a certain range(δ_(d)=17.5–18.0,δ_(p)=1–3.5,and δ_(h)=2–6),the extraction effect of bitumen from Indonesian oil sands improved,and the primary component affecting the extraction rate of bitumen were asphaltenes.展开更多
The paper presents an improved equivalent circuit parameters extraction method for the dumbbell-shaped defected ground structure (DGS). The new extraction parameters equations are obtained in closed-form expressions, ...The paper presents an improved equivalent circuit parameters extraction method for the dumbbell-shaped defected ground structure (DGS). The new extraction parameters equations are obtained in closed-form expressions, which contain S11 and S21. The DGS unit with center frequency of 5 GHz is designed and fabricated on a TLX substrate with thickness of 1 mm and dielectric constant of 2.55. The circuit simulated results are in good agreement with the measured results. This parameters extraction method can be widely used for the design and analysis of DGS .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
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
基金supported in part by the Natural Science Foundation of Zhejiang Province(LTGS23E070001).
文摘This paper proposes an improved version of the Partial Reinforcement Optimizer(PRO),termed LNPRO.The LNPRO has undergone a learner phase,which allows for further communication of information among the PRO population,changing the state of the PRO in terms of self-strengthening.Furthermore,the Nelder-Mead simplex is used to optimize the best agent in the population,accelerating the convergence speed and improving the accuracy of the PRO population.By comparing LNPRO with nine advanced algorithms in the IEEE CEC 2022 benchmark function,the convergence accuracy of the LNPRO has been verified.The accuracy and stability of simulated data and real data in the parameter extraction of PV systems are crucial.Compared to the PRO,the precision and stability of LNPRO have indeed been enhanced in four types of photovoltaic components,and it is also superior to other excellent algorithms.To further verify the parameter extraction problem of LNPRO in complex environments,LNPRO has been applied to three types of manufacturer data,demonstrating excellent results under varying irradiation and temperatures.In summary,LNPRO holds immense potential in solving the parameter extraction problems in PV systems.
文摘We improve the genetic algorithm by combining it with a simulated annealing algorithm. The improved algorithm is used to extract model parameters of SOI MOSFETs, which are fabricated with standard 1.2μm CMOS/SOI technology developed by the Institute of Microelectronics of the Chinese Academy of Sciences. The simulation results using this model are in excellent agreement with experimental results. The precision is improved noticeably compared to commercial software. This method requires neither a deeper understanding of SOl MOSFETs model nor more complex computations than conventional algorithms used by commercial software. Comprehensive verification shows that this model is applicable to a very large range of device sizes.
文摘A novel parameter extraction technique suitable f or short channel length lightly-doped-drain (LDD) MOSFET's is proposed which seg ments the total gate bias range,and executes the linear regression in every subs ections,yielding the gate bias dependent parameters,such as effective channel le ngth,parasitic resistance,and mobility,etc.This method avoids the gate bias rang e optimization,and retains the accuracy and simplicity of linear regression.The extracted gate bias dependent parameters are implemented in the compact I-V model which has been proposed for deep submicron LDD MOSFET's.The good agreemen ts between simulations and measurements of the devices on 0.18μm CMOS technolo gy indicate the effectivity of this technique.
基金funded by the Major R&D and Achievement Transformation Projects of Xizang(CGZH2024000416)Science and Technology Program of Xizang(XZ202402ZD0001)Major R&D and Achievement Transformation Projects of Qinghai(2022-QY-224)。
文摘Previous studies have often focused on monitoring grassland growth as the primary target of remote sensing investigations on grassland ecological restoration in the northern Tibetan Plateau,overlooking the crucial role played by gravel in the ecological restoration of these grasslands.This study utilizes supervised classification and segmentation techniques based on machine learning to extract gravel morphology profiles from field-sampled plot images and calculate their characteristic parameters.Employing a multivariate linear approach combined with Principal Component Analysis(PCA),a model for inferring gravel characteristic parameters is constructed.Statistical features,particle size characteristics,and spatial distribution patterns of gravel are analyzed.Results reveal that gravel predominantly exhibit sub-rounded shapes,with 80%classified as fine gravel.The coefficients of determination(R2)between gravel particle size and coverage,perimeter,and area are 0.444,0.724,and 0.557,respectively,indicating linear relationships.The cumulative contribution rate of the top five remote sensing factors is 95.44%,with the first geological factor contributing 77.64%,collectively reflecting the primary information of the 20 factors used.Modeling shows that areas with larger gravel particle sizes correspond to increased perimeter and coverage.Gravels in the Nagqu Prefecture of northern Xizang have a particle size range of 4-8 mm,primarily comprising fine gravel which accounts for 94.61%.These findings provide a scientific basis for extracting gravel characteristic parameters and understanding their spatial distribution variations in the northern Tibetan Plateau.
文摘A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experimental data. The extraction strategy is straightforward and can be easily implemented as a CAD tool to model spiral inductors. The resulting circuit models will be very useful for RF circuit designers.
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 sub circuit model for VDMOS is built according to its physical structure.Parameters and formulas describing the device are also derived from this model.Comparing to former results,this model avoids too many technical parameters and simplify the sub circuit efficiently.As a result of numeric computation,this simple model with clear physical conception demonstrates excellent agreements between measured and modeled response (DC error within 5%,AC error within 10%).Such a model is now available for circuit simulation and parameter extraction.
基金Project supported by the Joint Fund of the National Natural Science Foundation of China and the China Academy of Engineering Physics(Grant No.U1230112)
文摘Parameter extraction is an important step for circuit simulation methods that are based on physical models of semiconductor devices. A novel physical parameter extraction approach for Schottky diodes is proposed in this paper. By employing a set of analytical formulas, this approach extracts all of the necessary physical parameters of the diode chip in a unique way. It then extracts the package parasitic parameters with a curve-fitting method. To validate the proposed approach, a model HSMS-282 c commercial Schottky diode is taken as an example. Its physical parameters are extracted and used to simulate the diode＇s electrical characteristics. The simulated results based on the extracted parameters are compared with the measurements and a good agreement is obtained, which verifies the feasibility and accuracy of the proposed approach.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60936005 and 60976068)the New Century Excellent Talents of Ministry of Education of China (Grant No. NCET-05-0851)+1 种基金the Cultivation Fund of Key Scientific and Technical Innovation Project,Ministry of Education of China (Grant No. 708083)the Applied Materials Innovation Fund(Grant No. XA-AM-200701)
文摘Current transport mechanism in Ni-germanide/n-type Ge Schottky diodes is investigated using current-voltage characterisation technique with annealing temperatures from 300 ℃ to 500℃. Based on the current transport model, a simple method to extract parameters of the NiGe/Ge diode is presented by using the I-V characteristics. Parameters of NiGe/n-type Ge Schottky diodes fabricated for testing in this paper are as follows： the ideality factor n, the series resistance Rs, the zero-field barrier height Фb0, the interface state density Dit, and the interracial layer capacitance Ci. It is found that the ideality factor n of the diode increases with the increase of annealing temperature. As the temperature increases, the interface defects from the sputtering damage and the penetration of metallic states into the Ge energy gap are passivated, thus improving the junction quality. However, the undesirable crystallisations of Ni-germanide are observed together with NiGe at a temperature higher than 400℃. Depositing a very thin （-1 nm） heavily Ge-doped n＋ Ge intermediate layer can improve the NiGe film morphology significantly.
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.
基金Supported by the National Natural Science Foundation of China(61301189)111 Project of China(B14010)
文摘A phase-derived velocity measurement method is proposed in a wideband coherent system,based on a precise echo model considering the inner pulse Doppler effect caused by fast moving targets.The Cramer-Rao low band of velocity measurement precision is deduced,demonstrating the high precision of the proposed method.Simulations and out-field experiments further validate the effectiveness of the proposed method in high-precision measurement and micro-motion extraction for targets with weak reflection intensity.Compared with the long-time integration approaches for velocity measurement,the phase-derived method is easy to implement and meets the requirement for high data rate,which makes it suitable for micro-motion feature extraction in wideband systems.
基金supported by KEIT(0802DD-2007)funded by MKE(Ministry of Knowledge Economy)
文摘This paper describes a method to extract electrical parameters of the through via in Package-on-Package(PoP)with interposer.Using the de-embedding technique electrical parameters of the through via are extracted.With the extracted electrical parameters of the through via,the effects of via height,the distance between signal and GND vias,and anti-pad clearance on the electrical characteristics are discussed.
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.
基金Supported by the Project of National Key Laboratory Fund
文摘The method extracting the electromagnetic parameters from scattering coefficients was studied in this paper. The Support Vector Machine (SVM) method is used to solve the inverse problem of parameters extraction. The mapping relationship is set up by calculating a large number of S pa-rameters from the samples with different permittivity by using transmission line theory. The simulated data set is used as training data set for SVM. After the training, the SVM is used to predict the permittivity of material from the scattering coefficients.
基金Supported by the National Natural Science Foun dation of China(60444004)the AM Foundation of Shanghai Mu nicipal Science and Technology Commission of China(0109)
文摘An accurate and broad-band method for hetero-junction bipolar transistors(HBT)small-signal model parameters-extraction is presented in this paper.An equivalent circuit forthe HBT under a forward-bias condition is proposed for extraction of accessresistance and parasiticinductance.This method differs from previous ones by extracting the c-quivalent circuit parameterswithout using special test structure or global numerical optimization techniques.The mainadvantage of this method is that a unique and physically meaningful set of intrinsic parameters isextracted from impedance and admittance representation of the measured S-pa-rameters in thefrequency range of 1-12 GHz under different bias conditions.The method yields a deviation of lessthan 5%between measured and modeled S-parameters.
基金supported by the Natural Science Foundation of Jiangsu Province(Grant number:BK20140260)Joint Project of Industry-University-Research of Jiangsu Province(Grant number:BY2018158,BY2021590)State Key Laboratory of Heavy Oil Processing.
文摘Indonesian oil sands were systematically separated to investigate their basic composition.The extraction effects of the solvents with different Hilderbrand solubility parameters(HSPs)on the bitumen of Indonesian oil sands were compared.Furthermore,the Hansen solubility combination parameter(HSCP)and Teas triangle were used to explore rules in the separation of oil sands bitumen via solvent extraction.Finally,the saturates,aromatics,resins,and asphaltenes(SARA)fractions of the bitumen from Indonesian oil sands were analyzed.The results showed that the Indonesian oil sands were oil-wet with a bitumen content of 24.93%.The solvent extraction for bitumen could be accurately and conveniently selected based on the solubility parameter.When the HSPs of the extraction solvent were around 18–19 and the HSCPs were closer to a certain range(δ_(d)=17.5–18.0,δ_(p)=1–3.5,and δ_(h)=2–6),the extraction effect of bitumen from Indonesian oil sands improved,and the primary component affecting the extraction rate of bitumen were asphaltenes.
文摘The paper presents an improved equivalent circuit parameters extraction method for the dumbbell-shaped defected ground structure (DGS). The new extraction parameters equations are obtained in closed-form expressions, which contain S11 and S21. The DGS unit with center frequency of 5 GHz is designed and fabricated on a TLX substrate with thickness of 1 mm and dielectric constant of 2.55. The circuit simulated results are in good agreement with the measured results. This parameters extraction method can be widely used for the design and analysis of DGS .
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.
