The electrostatic discharge(ESD)protection circuit widely exists in the input and output ports of CMOS digital circuits,and fast rising time electromagnetic pulse(FREMP)coupled into the device not only interacts with ...The electrostatic discharge(ESD)protection circuit widely exists in the input and output ports of CMOS digital circuits,and fast rising time electromagnetic pulse(FREMP)coupled into the device not only interacts with the CMOS circuit,but also acts on the protection circuit.This paper establishes a model of on-chip CMOS electrostatic discharge protection circuit and selects square pulse as the FREMP signals.Based on multiple physical parameter models,it depicts the distribution of the lattice temperature,current density,and electric field intensity inside the device.At the same time,this paper explores the changes of the internal devices in the circuit under the injection of fast rising time electromagnetic pulse and describes the relationship between the damage amplitude threshold and the pulse width.The results show that the ESD protection circuit has potential damage risk,and the injection of FREMP leads to irreversible heat loss inside the circuit.In addition,pulse signals with different attributes will change the damage threshold of the circuit.These results provide an important reference for further evaluation of the influence of electromagnetic environment on the chip,which is helpful to carry out the reliability enhancement research of ESD protection circuit.展开更多
We propose a novel hybrid phase-locked loop (PLL) architecture for overcoming the trade-off between fast locking time and low spur. To reduce the settling time and meanwhile suppress the reference spurs, we employ a...We propose a novel hybrid phase-locked loop (PLL) architecture for overcoming the trade-off between fast locking time and low spur. To reduce the settling time and meanwhile suppress the reference spurs, we employ a wide-band single-path PLL and a narrow-band dual-path PLL in a transient state and a steady state, respectively, by changing the loop bandwidth according to the gain of voltage controlled oscillator (VCO) and the resister of the loop filter. The hybrid PLL is implemented in a 0.18-μm complementary metal oxide semiconductor (CMOS) process with a total die area of 1.4×0.46 mm2. The measured results exhibit a reference spur level of lower than -73 dB with a reference frequency of 10 MHz and a settling time of 20 μs with 40 MHz frequency jump at 2 GHz. The total power consumption of the hybrid PLL is less than 27 mW with a supply voltage of 1.8 V.展开更多
Incredible progress has been made in human action recognition(HAR),significantly impacting computer vision applications in sports analytics.However,identifying dynamic and complex movements in sports like badminton re...Incredible progress has been made in human action recognition(HAR),significantly impacting computer vision applications in sports analytics.However,identifying dynamic and complex movements in sports like badminton remains challenging due to the need for precise recognition accuracy and better management of complex motion patterns.Deep learning techniques like convolutional neural networks(CNNs),long short-term memory(LSTM),and graph convolutional networks(GCNs)improve recognition in large datasets,while the traditional machine learning methods like SVM(support vector machines),RF(random forest),and LR(logistic regression),combined with handcrafted features and ensemble approaches,perform well but struggle with the complexity of fast-paced sports like badminton.We proposed an ensemble learning model combining support vector machines(SVM),logistic regression(LR),random forest(RF),and adaptive boosting(AdaBoost)for badminton action recognition.The data in this study consist of video recordings of badminton stroke techniques,which have been extracted into spatiotemporal data.The three-dimensional distance between each skeleton point and the right hip represents the spatial features.The temporal features are the results of Fast Dynamic Time Warping(FDTW)calculations applied to 15 frames of each video sequence.The weighted ensemble model employs soft voting classifiers from SVM,LR,RF,and AdaBoost to enhance the accuracy of badminton action recognition.The E2 ensemble model,which combines SVM,LR,and AdaBoost,achieves the highest accuracy of 95.38%.展开更多
This brief article reviews a very particular and quite narrowfield,namely what has been done and what is needed to know for tannin adhesives for wood panels to succeed industrially.The present fashionable focus on bio...This brief article reviews a very particular and quite narrowfield,namely what has been done and what is needed to know for tannin adhesives for wood panels to succeed industrially.The present fashionable focus on bioadhe-sives has led to producing chemical adhesive formulations and approaches for tannin adhesives as a subject of academic publications.These,as good and original they might be,are and will still remain a rather empty aca-demic exercise if not put to the test of real industrial trials and industrial use.They will remain so without the“little”secrets and techniques outlined here that show that there is a great gap between developing an adhesive formulation in the laboratory and the hard reality to make it work where it does really count,in its industrial application.It outlines the fact that even more modern and excellent,newly developed bioadhesive formulations might well miserably fail once tried in the industry if the problems that always arise in their upgrading are not identified and solved,and solved well.It also outlines the fact that not only must costs always be taken into account and that a practical and possibly easy-to-handle approach must always be used,but too expensive or complex and unyielding adhesive systems are also often shown to be unusable or unsuitable in industry.展开更多
Two-dimensional(2D)materials have recently provided a new perspective on optoelectronics because of their unique layered structure and excellent physical properties.However,their potential use as optoelectric devices ...Two-dimensional(2D)materials have recently provided a new perspective on optoelectronics because of their unique layered structure and excellent physical properties.However,their potential use as optoelectric devices has been limited by the trade-off between photoresponsivity and response time.Here,based on a vertically stacked atomically thin p-n junction,we propose a gap-mode plasmon structure that simultaneously enables enhanced responsivity and rapid photodetection.The atomically thin 2D materials act as a spacer for enhancing the gap-mode plasmons,and their short transit length in the vertical direction allows fast photocarrier transport.We demonstrate a high responsivity of up to 8.67 A/W with a high operation speed that exceeds 35 MHz under a 30 nW laser power.Spectral photocurrent,absorption,and a numerical simulation are used to verify the effectiveness of the gap-mode plasmons in the device.We believe that the design strategy proposed in this study can pave the way for a platform to overcome the trade-off between responsivity and response time.展开更多
Two novel decyloxyphenylquinoxaline-based donor-acceptor (D-A) electroactive monomers bearing dialkoxythiophene as the donor unit are synthesized using Stille coupling reaction. The corresponding polymers, poly[2,3-...Two novel decyloxyphenylquinoxaline-based donor-acceptor (D-A) electroactive monomers bearing dialkoxythiophene as the donor unit are synthesized using Stille coupling reaction. The corresponding polymers, poly[2,3- bis(4-decyloxyphenyl)-5,8-bis(3,4-dimethoxylthiophen-2-yl)quinoxaline] (P1) and poly[2,3-bis(4-decyloxyphenyl)-5,8- bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)quinoxaline] (P2), are directly deposited onto the working electrode surface by electropolymerization. All materials were characterized by nuclear magnetic resonance (NMR), mass spectrometry (MS), scanning electron microscopy (SEM), cyclic voltammetry (CV), ultraviolet-visible absorption spectrometry (UV-Vis) and spectro-electrochemical measurements. Electrochemical studies demonstrate that both polymers are capable of showing both reasonable n- and p-doping processes, and advanced long-term switching stabilities. 3,4-Ethylenedioxythiophene substituted for 3,4-dimethoxythiophene as a donor unit, which enhances the conjugated double-bond character of the conducting polymer, thus leading to a lower electronic band-gap. Likewise, the neutral state color of the synthesized polymer tuned from blue to blue-green corresponding to the red shift of the maximum absorption wavelengths in the visible region. In addition, kinetics study of P1 revealed 42% (595 nm), 30% (839 nm) and 69% (1500 nm) transmittance changes (A7%), while P2 exhibited 32% (740 nm), 71% (2000 nm) at the dominant wavelengths. It was also observed that both films could switch quickly between the neutral state and oxidation state, with the response time less than 1 s both in visible and near infrared regions.展开更多
Background In high-energy and nuclear physics experiments,total absorption electromagnetic calorimeters made of inorganic crystals are known for their superb energy resolution and detection efficiency for photon and e...Background In high-energy and nuclear physics experiments,total absorption electromagnetic calorimeters made of inorganic crystals are known for their superb energy resolution and detection efficiency for photon and electron measurements.A crystal calorimeter is thus the choice for those experiments where precision measurements of photons and electrons are crucial for their physics missions.It is also known that the existing crystal detectors are neither bright nor fast enough nor radiation hard enough to survive severe radiation environment expected in future HEP experiments.Crystal detectors have also been proposed to build a homogeneous hadron calorimeter to achieve unprecedented jet mass resolution by duel readout of both Cherenkov and scintillation light,where the development of cost-effective crystal detectors is a crucial issue because of the 100 cubic meters crystal volume required.Purpose To develop novel inorganic crystal scintillatorbased detector concepts for future HEP experiments at the energy and intensity frontiers.Methods Optical and scintillation properties of novel inorganic crystal scintillators,such as excitation,emission and transmittance spectra,light output and decay time,are characterized before and after irradiation by ionization dose and hadrons.Their performance and radiation hardness are compared to the requirements,and feedback is given to the crystal manufacturers for quality improvement.Results As a result of this investigation,several inorganic crystal scintillator-based detector concepts are established for future HEP experiments,such as an LSO/LYSO crystalbased total absorption and/or sampling calorimeter concept,a barium fluoride crystal-based very fast crystal calorimeter concept,and a cost-effective inorganic scintillator-based homogeneous hadron calorimeter concept.Conclusion Bright,fast and radiation hard LYSO/LSO crystals may be used for a total absorption ECAL.An LYSO/W Shashlik sampling calorimeter will survive the harsh radiation environment expected at the HL-LHC.With sub-ns decay time of its fast scintillation component and excellent radiation hardness,barium fluoride crystals would provide more than ten times faster rate and timing capability,provided that their slow scintillation component is effectively suppressed to avoid pileup.PbF2,PbFCl and BSO crystals may provide a foundation for a homogeneous hadron calorimeter with dual readout for both Cherenkov and scintillation light to achieve unprecedented jet mass resolution for future lepton colliders.展开更多
基金National Natural Science Foundation of China(61974116)。
文摘The electrostatic discharge(ESD)protection circuit widely exists in the input and output ports of CMOS digital circuits,and fast rising time electromagnetic pulse(FREMP)coupled into the device not only interacts with the CMOS circuit,but also acts on the protection circuit.This paper establishes a model of on-chip CMOS electrostatic discharge protection circuit and selects square pulse as the FREMP signals.Based on multiple physical parameter models,it depicts the distribution of the lattice temperature,current density,and electric field intensity inside the device.At the same time,this paper explores the changes of the internal devices in the circuit under the injection of fast rising time electromagnetic pulse and describes the relationship between the damage amplitude threshold and the pulse width.The results show that the ESD protection circuit has potential damage risk,and the injection of FREMP leads to irreversible heat loss inside the circuit.In addition,pulse signals with different attributes will change the damage threshold of the circuit.These results provide an important reference for further evaluation of the influence of electromagnetic environment on the chip,which is helpful to carry out the reliability enhancement research of ESD protection circuit.
基金supported by the National Natural Science Foundation of China(Grant No.61307128)the National Basic Research Program of China(GrantNo.2010CB327505)+1 种基金the Specialized Research Found for the Doctoral Program of Higher Education of China(Grant No.20131101120027)the Basic Research Foundation of Beijing Institute of Technology of China(Grant No.20120542015)
文摘We propose a novel hybrid phase-locked loop (PLL) architecture for overcoming the trade-off between fast locking time and low spur. To reduce the settling time and meanwhile suppress the reference spurs, we employ a wide-band single-path PLL and a narrow-band dual-path PLL in a transient state and a steady state, respectively, by changing the loop bandwidth according to the gain of voltage controlled oscillator (VCO) and the resister of the loop filter. The hybrid PLL is implemented in a 0.18-μm complementary metal oxide semiconductor (CMOS) process with a total die area of 1.4×0.46 mm2. The measured results exhibit a reference spur level of lower than -73 dB with a reference frequency of 10 MHz and a settling time of 20 μs with 40 MHz frequency jump at 2 GHz. The total power consumption of the hybrid PLL is less than 27 mW with a supply voltage of 1.8 V.
基金supported by the Center for Higher Education Funding(BPPT)and the Indonesia Endowment Fund for Education(LPDP),as acknowledged in decree number 02092/J5.2.3/BPI.06/9/2022。
文摘Incredible progress has been made in human action recognition(HAR),significantly impacting computer vision applications in sports analytics.However,identifying dynamic and complex movements in sports like badminton remains challenging due to the need for precise recognition accuracy and better management of complex motion patterns.Deep learning techniques like convolutional neural networks(CNNs),long short-term memory(LSTM),and graph convolutional networks(GCNs)improve recognition in large datasets,while the traditional machine learning methods like SVM(support vector machines),RF(random forest),and LR(logistic regression),combined with handcrafted features and ensemble approaches,perform well but struggle with the complexity of fast-paced sports like badminton.We proposed an ensemble learning model combining support vector machines(SVM),logistic regression(LR),random forest(RF),and adaptive boosting(AdaBoost)for badminton action recognition.The data in this study consist of video recordings of badminton stroke techniques,which have been extracted into spatiotemporal data.The three-dimensional distance between each skeleton point and the right hip represents the spatial features.The temporal features are the results of Fast Dynamic Time Warping(FDTW)calculations applied to 15 frames of each video sequence.The weighted ensemble model employs soft voting classifiers from SVM,LR,RF,and AdaBoost to enhance the accuracy of badminton action recognition.The E2 ensemble model,which combines SVM,LR,and AdaBoost,achieves the highest accuracy of 95.38%.
文摘This brief article reviews a very particular and quite narrowfield,namely what has been done and what is needed to know for tannin adhesives for wood panels to succeed industrially.The present fashionable focus on bioadhe-sives has led to producing chemical adhesive formulations and approaches for tannin adhesives as a subject of academic publications.These,as good and original they might be,are and will still remain a rather empty aca-demic exercise if not put to the test of real industrial trials and industrial use.They will remain so without the“little”secrets and techniques outlined here that show that there is a great gap between developing an adhesive formulation in the laboratory and the hard reality to make it work where it does really count,in its industrial application.It outlines the fact that even more modern and excellent,newly developed bioadhesive formulations might well miserably fail once tried in the industry if the problems that always arise in their upgrading are not identified and solved,and solved well.It also outlines the fact that not only must costs always be taken into account and that a practical and possibly easy-to-handle approach must always be used,but too expensive or complex and unyielding adhesive systems are also often shown to be unusable or unsuitable in industry.
基金This work was supported by the National Research Foundation of Korea(NRF)through Basic Research Program(No.2019R1A2C2009171)Creative Materials Discovery Program(No.2016M3D1A1900035).
文摘Two-dimensional(2D)materials have recently provided a new perspective on optoelectronics because of their unique layered structure and excellent physical properties.However,their potential use as optoelectric devices has been limited by the trade-off between photoresponsivity and response time.Here,based on a vertically stacked atomically thin p-n junction,we propose a gap-mode plasmon structure that simultaneously enables enhanced responsivity and rapid photodetection.The atomically thin 2D materials act as a spacer for enhancing the gap-mode plasmons,and their short transit length in the vertical direction allows fast photocarrier transport.We demonstrate a high responsivity of up to 8.67 A/W with a high operation speed that exceeds 35 MHz under a 30 nW laser power.Spectral photocurrent,absorption,and a numerical simulation are used to verify the effectiveness of the gap-mode plasmons in the device.We believe that the design strategy proposed in this study can pave the way for a platform to overcome the trade-off between responsivity and response time.
基金financially supported by the National Natural Science Foundation of China(Nos.51473074 and 31400044)the General and Special Program of the Postdoctoral Science Foundation China(Nos.2013M530397 and 2014T70861)+1 种基金the Postgraduate Innovation Project of China University of Petroleum(East China)(No.YCX2015022)the Fundamental Research Funds for the Central Universities(No.15CX06049A)
文摘Two novel decyloxyphenylquinoxaline-based donor-acceptor (D-A) electroactive monomers bearing dialkoxythiophene as the donor unit are synthesized using Stille coupling reaction. The corresponding polymers, poly[2,3- bis(4-decyloxyphenyl)-5,8-bis(3,4-dimethoxylthiophen-2-yl)quinoxaline] (P1) and poly[2,3-bis(4-decyloxyphenyl)-5,8- bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)quinoxaline] (P2), are directly deposited onto the working electrode surface by electropolymerization. All materials were characterized by nuclear magnetic resonance (NMR), mass spectrometry (MS), scanning electron microscopy (SEM), cyclic voltammetry (CV), ultraviolet-visible absorption spectrometry (UV-Vis) and spectro-electrochemical measurements. Electrochemical studies demonstrate that both polymers are capable of showing both reasonable n- and p-doping processes, and advanced long-term switching stabilities. 3,4-Ethylenedioxythiophene substituted for 3,4-dimethoxythiophene as a donor unit, which enhances the conjugated double-bond character of the conducting polymer, thus leading to a lower electronic band-gap. Likewise, the neutral state color of the synthesized polymer tuned from blue to blue-green corresponding to the red shift of the maximum absorption wavelengths in the visible region. In addition, kinetics study of P1 revealed 42% (595 nm), 30% (839 nm) and 69% (1500 nm) transmittance changes (A7%), while P2 exhibited 32% (740 nm), 71% (2000 nm) at the dominant wavelengths. It was also observed that both films could switch quickly between the neutral state and oxidation state, with the response time less than 1 s both in visible and near infrared regions.
基金This work is supported by the U.S.Department of Energy,Office of High Energy Physics program under Award Number DE-SC0011925.
文摘Background In high-energy and nuclear physics experiments,total absorption electromagnetic calorimeters made of inorganic crystals are known for their superb energy resolution and detection efficiency for photon and electron measurements.A crystal calorimeter is thus the choice for those experiments where precision measurements of photons and electrons are crucial for their physics missions.It is also known that the existing crystal detectors are neither bright nor fast enough nor radiation hard enough to survive severe radiation environment expected in future HEP experiments.Crystal detectors have also been proposed to build a homogeneous hadron calorimeter to achieve unprecedented jet mass resolution by duel readout of both Cherenkov and scintillation light,where the development of cost-effective crystal detectors is a crucial issue because of the 100 cubic meters crystal volume required.Purpose To develop novel inorganic crystal scintillatorbased detector concepts for future HEP experiments at the energy and intensity frontiers.Methods Optical and scintillation properties of novel inorganic crystal scintillators,such as excitation,emission and transmittance spectra,light output and decay time,are characterized before and after irradiation by ionization dose and hadrons.Their performance and radiation hardness are compared to the requirements,and feedback is given to the crystal manufacturers for quality improvement.Results As a result of this investigation,several inorganic crystal scintillator-based detector concepts are established for future HEP experiments,such as an LSO/LYSO crystalbased total absorption and/or sampling calorimeter concept,a barium fluoride crystal-based very fast crystal calorimeter concept,and a cost-effective inorganic scintillator-based homogeneous hadron calorimeter concept.Conclusion Bright,fast and radiation hard LYSO/LSO crystals may be used for a total absorption ECAL.An LYSO/W Shashlik sampling calorimeter will survive the harsh radiation environment expected at the HL-LHC.With sub-ns decay time of its fast scintillation component and excellent radiation hardness,barium fluoride crystals would provide more than ten times faster rate and timing capability,provided that their slow scintillation component is effectively suppressed to avoid pileup.PbF2,PbFCl and BSO crystals may provide a foundation for a homogeneous hadron calorimeter with dual readout for both Cherenkov and scintillation light to achieve unprecedented jet mass resolution for future lepton colliders.