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A Reverse Path Planning Approach for Enhanced Performance of Multi-Degree-of-Freedom Industrial Manipulators
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作者 Zhiwei Lin Hui Wang +3 位作者 Tianding Chen Yingtao Jiang Jianmei Jiang Yingpin Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1357-1379,共23页
In the domain of autonomous industrial manipulators,precise positioning and appropriate posture selection in path planning are pivotal for tasks involving obstacle avoidance,such as handling,heat sealing,and stacking.... In the domain of autonomous industrial manipulators,precise positioning and appropriate posture selection in path planning are pivotal for tasks involving obstacle avoidance,such as handling,heat sealing,and stacking.While Multi-Degree-of-Freedom(MDOF)manipulators offer kinematic redundancy,aiding in the derivation of optimal inverse kinematic solutions to meet position and posture requisites,their path planning entails intricate multiobjective optimization,encompassing path,posture,and joint motion optimization.Achieving satisfactory results in practical scenarios remains challenging.In response,this study introduces a novel Reverse Path Planning(RPP)methodology tailored for industrial manipulators.The approach commences by conceptualizing the manipulator’s end-effector as an agent within a reinforcement learning(RL)framework,wherein the state space,action set,and reward function are precisely defined to expedite the search for an initial collision-free path.To enhance convergence speed,the Q-learning algorithm in RL is augmented with Dyna-Q.Additionally,we formulate the cylindrical bounding box of the manipulator based on its Denavit-Hartenberg(DH)parameters and propose a swift collision detection technique.Furthermore,the motion performance of the end-effector is refined through a bidirectional search,and joint weighting coefficients are introduced to mitigate motion in high-power joints.The efficacy of the proposed RPP methodology is rigorously examined through extensive simulations conducted on a six-degree-of-freedom(6-DOF)manipulator encountering two distinct obstacle configurations and target positions.Experimental results substantiate that the RPP method adeptly orchestrates the computation of the shortest collision-free path while adhering to specific posture constraints at the target point.Moreover,itminimizes both posture angle deviations and joint motion,showcasing its prowess in enhancing the operational performance of MDOF industrial manipulators. 展开更多
关键词 reverse path planning Dyna-Q bidirectional search posture angle joint motion
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Triple reverse order law for the Drazin inverse
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作者 WANG Hua ZHONG Cheng-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期55-68,共14页
In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation relations.Moreover,the Drazin invertibility of sum is also obtained for two bounded linea... In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation relations.Moreover,the Drazin invertibility of sum is also obtained for two bounded linear operators and its expression is presented. 展开更多
关键词 Drazin inverse reverse order law space decomposition
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Mass transfer process of peanut protein extracted by bis(2-ethylhexyl)sodium sulfosuccinate reverse micelles
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作者 Chenxian Yang Tianci Li +5 位作者 Tingwei Zhu Xiaojie Duan Yibao Chen Yandong Xu Fusheng Chen Kunlun Liu 《Grain & Oil Science and Technology》 CAS 2024年第1期60-67,共8页
The liquid-liquid extraction method using reverse micelles can simultaneously extract lipid and protein of oilseeds,which have become increasingly popular in recent years.However,there are few studies on mass transfer... The liquid-liquid extraction method using reverse micelles can simultaneously extract lipid and protein of oilseeds,which have become increasingly popular in recent years.However,there are few studies on mass transfer processes and models,which are helpful to better control the extraction process of oils and proteins.In this paper,mass transfer process of peanut protein extracted by bis(2-ethylhexyl)sodium sulfosuccinate(AOT)/isooctane reverse micelles was investigated.The effects of stirring speed(0,70,140,and 210 r/min),temperature of extraction(30,35,40,45,and 50℃),peanut flour particle size(0.355,0.450,0.600,and 0.900 mm)and solidliquid ratio(0.010,0.0125,0.015,0.0175,and 0.020 g/mL)on extraction rate were examined.The results showed that extraction rate increased with temperature rising,particle size reduction as well as solid-liquid ratio increase respectively,while little effect of stirring speed(P>0.05)was observed.The apparent activation energy of extraction process was calculated as 10.02 kJ/mol and Arrhenius constant(A)was 1.91 by Arrhenius equation.There was a linear relationship between reaction rate constant and the square of the inverse of initial particle radius(1/r_(0)^(2))(P<0.05).This phenomenon and this shrinking core model were anastomosed.In brief,the extraction process was controlled by the diffusion of protein from the virgin zone interface of particle through the reacted zone and it was in line with the first order reaction.Mass transfer kinetics of peanut protein extracted by reverse micelles was established and it was verified by experimental results.The results provide an important theoretical guidance for industrial production of peanut protein separation and purification. 展开更多
关键词 AOT reverse micelles Peanut protein KINETICS Shrinking core model Mass transfer
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Exceptional reversed yield strength asymmetry in a rare-earth free Mg alloy containing quasicrystal precipitates
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作者 Qiang Yang Shuhui Lv +2 位作者 Zixiang Yan Zefeng Xie Xin Qiu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期687-699,共13页
This work reports an exceptional reversed yield strength asymmetry at room temperature for a rare-earth free magnesium alloy containing a mass of fine dispersed quasicrystal(I-phase)precipitates.Although exhibiting tr... This work reports an exceptional reversed yield strength asymmetry at room temperature for a rare-earth free magnesium alloy containing a mass of fine dispersed quasicrystal(I-phase)precipitates.Although exhibiting traditional basal texture,it owns an exceptional CYS/TYS as high as~1.17.Electron back-scattered diffraction(EBSD)and transmission electron microscopy(TEM)examinations indicate pyramidal and prismatic dislocations plus tensile twinning being activated after immediate yielding in compression while basal and non-basal dislocations in tension.I-phase particles transferred the concentrated stress by self-twinning to provide the driving force for tensile twin initiating in neighboring grains,thereby significantly increasing the critical resolved shear stress of tensile twinning to possibly the level of pyramidal slip,finally leading to the dominance of pyramidal slip plus tensile twinning in texture grains.This results in a higher contribution on yield strength by~55 MPa in compression than in tension,which reasonably agrees with the experimental yield strength difference(~38 MPa).It can be concluded that I-phase particles influence deformation modes in tension and in compression,finally result in reversed yield strength asymmetry. 展开更多
关键词 Magnesium alloy reversed yield strength asymmetry Transmission electron microscopy(TEM) TWINNING Dislocations
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The Inheritance and Application of Chinese Reverse Contrast Typeface Style
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作者 Suimeng Qin Albert Young Choi 《Psychology Research》 2024年第2期70-80,共11页
This paper discusses the inheritance and application of Chinese character reverse contrast typeface style.It begins by analyzing the visual features of Western reverse contrast typeface styles,with a focus on Caslon I... This paper discusses the inheritance and application of Chinese character reverse contrast typeface style.It begins by analyzing the visual features of Western reverse contrast typeface styles,with a focus on Caslon Italian and French Clarendon,providing a Western perspective reference for subsequent Chinese character reverse contrast typeface style designs.The paper then traces the origins of the Chinese reverse contrast style,from the calligraphy style"Lacquer Script"to the earliest printing type"フワンテール形",exploring the historical background and cultural significance of the Chinese reverse contrast style.In the methodology section of Chinese character reverse contrast typeface style design,the discussion is conducted from two dimensions:inheritance and application.In terms of inheritance,through an in-depth analysis of"Lacquer Script"and"フワンテール形"typeface style,the paper summarizes three basic theories for modern Chinese character reverse contrast typeface style design.In the application section,it examines in detail the two most influential recent typeface styles,"Ribaasu"and"Basic Artistic",outlining three directions of application:extreme horizontal stroke variations,exaggerated contrast,and diverse decorative strokes,showcasing new directions and possibilities for Chinese character reverse contrast typeface style design.This paper not only reviews the developmental history of the Chinese character reverse contrast typeface style but also analyzes the design methodology of Chinese character reverse contrast typeface style through specific case studies. 展开更多
关键词 reverse contrast fonts Chinese character font design design method
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Stresses in the Scapular Fossa Do Not Exceed the Yield Stress When Elevated up to 135 Degrees of Abduction after Reverse Shoulder Arthroplasty
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作者 Rina Sakai Tomonori Kenmoku +3 位作者 Ryo Tazawa Kazuhiro Yoshida Tomomi Mizuhashi Masanobu Ujihira 《Journal of Biomedical Science and Engineering》 2024年第2期35-40,共6页
Reverse shoulder arthroplasty (RSA) is an effective treatment for rotator cuff tears. Despite its advantages, complications occur at a high rate. Complications requiring revision include a high rate of base plate fail... Reverse shoulder arthroplasty (RSA) is an effective treatment for rotator cuff tears. Despite its advantages, complications occur at a high rate. Complications requiring revision include a high rate of base plate failure, 38% of which are due to instability. The primary stability the base plate ensures is a crucial factor and, thus, is the subject of much debate in clinical studies and biomechanical research. This study is aimed to provide data that will contribute to the base plate’s pri-mary stability and glenoid longevity by clarifying the stresses at the scapular fossa and base plate interface associated with elevation after RSA. A 3D finite element model was created from the DICOM data for the scapulohumeral joint and SMR shoulder system. For loading conditions, 30 N was applied for each posi-tion with abduction angles of 0, 45, 90, and 135 degrees. A three-dimensional fi-nite element analysis was performed using the static implicit method with LS-DYNA. The von Mises stresses in the scapular fossa were found not to exceed the yield stress on the bone even after elevation to an abduction angle of 135 de-grees after RSA. It is rough to uniformly compare the yield stress and the von Mises stress, but it was inferred that the possibility of fracture is low unless a large external force is applied. A maximum von Mises stress showed 0 degrees of abduction, suggesting that the lowered position is in a more severe condition than the elevated position. If better improvement is desired, it may be necessary to devise ways to reduce the stress on the upper screw. . 展开更多
关键词 reverse Shoulder Arthroplasty Finite Element Analysis Yield Stress GLENOID
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Impacts of Climate Change on Seawater Temperature and Total Dissolved Solids: Challenges and Sustainable Solutions for Reverse Osmosis Desalination in the Arabian Gulf Region
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作者 Ahmed Al Kubaish Jamal Salama 《Computational Water, Energy, and Environmental Engineering》 2024年第1期86-93,共8页
This article examines the influence of seawater temperature and total dissolved solids (TDS) on reverse osmosis (RO) desalination in the Arabian Gulf region, with a focus on the impact of climate change. The study hig... This article examines the influence of seawater temperature and total dissolved solids (TDS) on reverse osmosis (RO) desalination in the Arabian Gulf region, with a focus on the impact of climate change. The study highlights the changes in seawater temperature and TDS levels over the years and discusses their effects on the efficiency and productivity of RO desalination plants. It emphasizes the importance of monitoring TDS levels and controlling seawater temperature to optimize water production. The article also suggests various solutions, including intensive pre-treatment, development of high-performance membranes, exploration of alternative water sources, and regulation of discharges into the Gulf, to ensure sustainable water supply in the face of rising TDS levels and seawater temperature. Further research and comprehensive monitoring are recommended to understand the implications of these findings and develop effective strategies for the management of marine resources in the Arabian Gulf. 展开更多
关键词 Climate Change TEMPERATURE reverse Osmosis Seawater Total Dissolved Solids DESALINATION
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Reversed charge transfer induced by nickel in Fe-Ni/Mo_(2)C@nitrogen-doped carbon nanobox for promoted reversible oxygen electrocatalysis
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作者 Zhicheng Nie Lei Zhang +4 位作者 Qiliang Zhu Zhifan Ke Yingtang Zhou Thomas Wågberg Guangzhi Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期202-212,I0005,共12页
The interaction between metal and support is critical in oxygen catalysis as it governs the charge transfer between these two entities,influences the electronic structures of the supported metal,affects the adsorption... The interaction between metal and support is critical in oxygen catalysis as it governs the charge transfer between these two entities,influences the electronic structures of the supported metal,affects the adsorption energies of reaction intermediates,and ultimately impacts the catalytic performance.In this study,we discovered a unique charge transfer reversal phenomenon in a metal/carbon nanohybrid system.Specifically,electrons were transferred from the metal-based species to N-doped carbon,while the carbon support reciprocally donated electrons to the metal domain upon the introduction of nickel.This led to the exceptional electrocatalytic performances of the resulting Ni-Fe/Mo_(2)C@nitrogen-doped carbon catalyst,with a half-wave potential of 0.91 V towards oxygen reduction reaction(ORR)and a low overpotential of 290 m V at 10 mA cm^(-2)towards oxygen evolution reaction(OER)under alkaline conditions.Additionally,the Fe-Ni/Mo_(2)C@carbon heterojunction catalyst demonstrated high specific capacity(794 mA h g_(Zn)~(-1))and excellent cycling stability(200 h)in a Zn-air battery.Theoretical calculations revealed that Mo_(2)C effectively inhibited charge transfer from Fe to the support,while secondary doping of Ni induced a charge transfer reversal,resulting in electron accumulation in the Fe-Ni alloy region.This local electronic structure modulation significantly reduced energy barriers in the oxygen catalysis process,enhancing the catalytic efficiency of both ORR and OER.Consequently,our findings underscore the potential of manipulating charge transfer reversal between the metal and support as a promising strategy for developing highly-active and durable bi-functional oxygen electrodes. 展开更多
关键词 Metal-support interaction Charge transfer reversal Oxygen reduction reaction Oxygen evolution reaction Zinc-air battery
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A novel cationic collector for silicon removal from collophane using reverse flotation under acidic conditions 被引量:1
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作者 Zhongxian Wu Dongping Tao +2 位作者 Youjun Tao Man Jiang Patrick Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1038-1047,共10页
We analyzed a novel cationic collector using chemical plant byproducts,such as cetyltrimethylammonium bromide(CTAB)and dibutyl phthalate(DBP).Our aim is to establish a highly effective and economical process for the r... We analyzed a novel cationic collector using chemical plant byproducts,such as cetyltrimethylammonium bromide(CTAB)and dibutyl phthalate(DBP).Our aim is to establish a highly effective and economical process for the removal of quartz from collophane.A microflotation test with a 25 mg·L^(−1)collector at pH value of 6-10 demonstrates a considerable difference in the floatability of pure quartz and fluorapatite.Flotation tests for a collophane sample subjected to the first reverse flotation for magnesium removal demonstrates that a rough flotation process(using a 0.4 kg·t−1 new collector at pH=6)results in a collophane concentrate with 29.33wt%P_(2)O_(5)grade and 12.66wt%SiO2 at a 79.69wt%P_(2)O_(5)recovery,providing desirable results.Mechanism studies using Fourier transform infrared spectroscopy,zeta potential,and contact angle measurements show that the adsorption capacity of the new collector for quartz is higher than that for fluorapatite.The synergistic effect of DBP increases the difference in hydrophobicity between quartz and fluorapatite.The maximum defoaming rate of the novel cationic collector reaches 142.8 mL·min−1.This is considerably higher than that of a conventional cationic collector. 展开更多
关键词 cationic collector collophane DEFOAMING QUARTZ reverse flotation
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A novel SiC high-k superjunction power MOSFET integrated Schottky barrier diode with improved forward and reverse performance
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作者 Moufu Kong Zewei Hu +3 位作者 Ronghe Yan Bo Yi Bingke Zhang Hongqiang Yang 《Journal of Semiconductors》 EI CAS CSCD 2023年第5期53-61,共9页
A new SiC superjunction power MOSFET device using high-k insulator and p-type pillar with an integrated Schottky barrier diode(Hk-SJ-SBD MOSFET)is proposed,and has been compared with the SiC high-k MOSFET(Hk MOSFET),S... A new SiC superjunction power MOSFET device using high-k insulator and p-type pillar with an integrated Schottky barrier diode(Hk-SJ-SBD MOSFET)is proposed,and has been compared with the SiC high-k MOSFET(Hk MOSFET),SiC superjuction MOSFET(SJ MOSFET)and the conventional SiC MOSFET in this article.In the proposed SiC Hk-SJ-SBD MOSFET,under the combined action of the p-type region and the Hk dielectric layer in the drift region,the concentration of the N-drift region and the current spreading layer can be increased to achieve an ultra-low specific on-resistance(Ron,sp).The integrated Schottky barrier diode(SBD)also greatly improves the reverse recovery performance of the device.TCAD simulation results indicate that the Ron,sp of the proposed SiC Hk-SJ-SBD MOSFET is 0.67 mΩ·cm^(2)with a 2240 V breakdown voltage(BV),which is more than 72.4%,23%,5.6%lower than that of the conventional SiC MOSFET,Hk SiC MOSFET and SJ SiC MOSFET with the 1950,2220,and 2220V BV,respectively.The reverse recovery time and reverse recovery charge of the proposed MOSFET is 16 ns and18 nC,which are greatly reduced by more than 74%and 94%in comparison with those of all the conventional SiC MOSFET,Hk SiC MOSFET and SJ SiC MOSFET,due to the integrated SBD in the proposed MOSFET.And the trade-off relationship between the Ron,sp and the BV is also significantly improved compared with that of the conventional MOSFET,Hk MOSFET and SJ MOSFET as well as the MOSFETs in other previous literature,respectively.In addition,compared with conventional SJ SiC MOSFET,the proposed SiC MOSFET has better immunity to charge imbalance,which may bring great application prospects. 展开更多
关键词 SIC MOSFET specific on-resistance breakdown voltage HIGH-K SUPERJUNCTION switching performance reverse recovery characteristic
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An integrated split and dummy gates MOSFET with fast turn-off and reverse recovery characteristics
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作者 陈伟中 牟柳亭 +2 位作者 秦海峰 张红升 韩郑生 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期545-550,共6页
A power MOSFET with integrated split gate and dummy gate(SD-MOS) is proposed and demonstrated by the TCAD SENTAURUS.The split gate is surrounded by the source and shielded by the dummy gate.Consequently,the coupling a... A power MOSFET with integrated split gate and dummy gate(SD-MOS) is proposed and demonstrated by the TCAD SENTAURUS.The split gate is surrounded by the source and shielded by the dummy gate.Consequently,the coupling area between the split gate and the drain electrode is reduced,thus the gate-to-drain charge(Q_(GD)),reverse transfer capacitance(C_(RSS)) and turn-off loss(E_(off)) are significantly decreased.Moreover,the MOS-channel diode is controlled by the dummy gate with ultra-thin gate oxide t_(ox),which can be turned on before the parasitic P-base/N-drift diode at the reverse conduction,then the majority carriers are injected to the N-drift to attenuate the minority injection.Therefore,the reverse recovery charge(Q_(RR)),time(T_(RR)) and peak current(I_(RRM)) are effectively reduced at the reverse freewheeling state.Additionally,the specific on-resistance(R_(on,sp)) and breakdown voltage(BV) are also studied to evaluate the static properties of the proposed SD-MOS.The simulation results show that the Q_(GD) of 6 nC/cm^(2),the C_(RSS) of 1.1 pF/cm^(2) at the V_(DS) of 150 V,the QRR of 1.2 μC/cm^(2) and the R_(on,sp) of 8.4 mΩ·cm^(2) are obtained,thus the figures of merit(FOM) including Q_(GD) ×R_(on,sp) of50 nC·mΩ,E_(off) × R_(on,sp) of 0.59 mJ·mΩ and the Q_(RR) × R_(on,sp) of 10.1 μC·mΩ are achieved for the proposed SD-MOS. 展开更多
关键词 MOSFET split gate dummy gate TURN-OFF and reverse recovery
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Double Layer Composite Electrode Strategy for Efficient Perovskite Solar Cells with Excellent Reverse-Bias Stability
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作者 Chaofan Jiang Junjie Zhou +6 位作者 Hang Li Liguo Tan Minghao Li Wolfgang Tress Liming Ding Michael Grätzel Chenyi Yi 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第1期225-235,共11页
Perovskite solar cells(PSCs)have become the represent-atives of next generation of photovoltaics;nevertheless,their stability is insufficient for large scale deployment,particularly the reverse bias stability.Here,we ... Perovskite solar cells(PSCs)have become the represent-atives of next generation of photovoltaics;nevertheless,their stability is insufficient for large scale deployment,particularly the reverse bias stability.Here,we propose a transparent conducting oxide(TCO)and low-cost metal composite electrode to improve the stability of PSCs without sacrificing the efficiency.The TCO can block ion migrations and chemical reactions between the metal and perovskite,while the metal greatly enhances the conductivity of the composite electrode.As a result,composite electrode-PSCs achieved a power conversion efficiency(PCE)of 23.7%(certified 23.2%)and exhibited excellent stability,maintaining 95%of the initial PCE when applying a reverse bias of 4.0 V for 60 s and over 92%of the initial PCE after 1000 h continuous light soaking.This composite electrode strategy can be extended to different combinations of TCOs and metals.It opens a new avenue for improving the stability of PSCs. 展开更多
关键词 Composite electrode Perovskite solar cells STABILITY reverse bias Characterization
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Novel double channel reverse conducting GaN HEMT with an integrated MOS-channel diode
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作者 谢欣桐 张成 +3 位作者 赵智家 魏杰 罗小蓉 张波 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期97-102,共6页
A novel normally-off double channel reverse conducting(DCRC)HEMT with an integrated MOS-channel diode(MCD)is proposed and investigated by TCAD simulation.The proposed structure has two features:one is double heterojun... A novel normally-off double channel reverse conducting(DCRC)HEMT with an integrated MOS-channel diode(MCD)is proposed and investigated by TCAD simulation.The proposed structure has two features:one is double heterojunctions to form dual 2DEG channels named the 1^(st)path and the 2^(nd)path for reverse conduction,and the other is the MCD forming by the trench source metal,source dielectric,and Ga N.At the initial reverse conduction stage,the MCD acts as a switch to control the 1^(st)path which would be turned on prior to the 2^(nd)path.Because of the introduction of the 1^(st)path,the DCRC-HEMT has an additional reverse conducting channel to help enhance the reverse conduction performance.Compared with the conventional HEMT(Conv.HEMT),the DCRC-HEMT can obtain a low reverse turn-on voltage(VRT)and its VRTis independent of the gate-source bias(VGS)at the same time.The DCRC-HEMT achieves the VRTof 0.62 V,which is 59.7%and 75.9%lower than that of the Conv.HEMT at VGS=0 V and-1 V,respectively.In addition,the forward conduction capability and blocking characteristics almost remain unchanged.In the end,the key fabrication flows of DCRC-HEMT are presented. 展开更多
关键词 ALGAN/GAN HEMT double-channel reverse conduction
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Proper orthogonal decomposition based seismic source wavefield reconstruction for finite element reverse time migration
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作者 Wen-Zhuo Tan Bang-Yu Wu +1 位作者 Rui Li Bo Li 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期199-211,共13页
The large storage requirement is a critical issue in cross-correlation imaging-condition based reverse time migration(RTM),because it requires the operation of the source and receiver wavefields at the same time.The b... The large storage requirement is a critical issue in cross-correlation imaging-condition based reverse time migration(RTM),because it requires the operation of the source and receiver wavefields at the same time.The boundary value method(BVM),based on the finite difference method(FDM),can be used to reconstruct the source wavefield in the reverse time propagation in the same way as the receiver wavefield,which can reduce the storage burden of the RTM data.Considering that the FDM cannot well handle models with discontinuous material properties and rough interfaces,we develop a source wavefield reconstruction strategy based on the finite element method(FEM),using proper orthogonal decomposition(POD)to enhance computational efficiency.In this method,we divide the whole time period into several segments,and construct the POD basis functions to get a reduced order model(ROM)for the source wavefield reconstruction in each segment.We show the corresponding quantitative analysis of the storage requirement of the POD-FEM.Numerical tests on the homogeneous model show the effectiveness of the proposed method,while the layered model and part of the Marmousi model tests indicate that the POD-FEM can keep an excellent balance between computational efficiency and memory usage compared with the full-stored method(FSM)and the BVM,and can be effectively applied in imaging. 展开更多
关键词 reverse time migration Seismic wavefield reconstruction Finite element modeling Proper orthogonal decomposition
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Stable attenuation-compensated reverse time migration and its application to land seismic data
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作者 Xin-Ru Mu Qiang Mao Jian-Ping Huang 《Petroleum Science》 SCIE EI CSCD 2023年第5期2784-2795,共12页
Intrinsic attenuation of the earth causes energy loss and phase distortion in seismic wave propagation.To obtain high-resolution imaging results,these negative effects must be considered during reverse time migration(... Intrinsic attenuation of the earth causes energy loss and phase distortion in seismic wave propagation.To obtain high-resolution imaging results,these negative effects must be considered during reverse time migration(RTM).We can easily implement attenuation-compensated RTM using the constant Q viscoacoustic wave equation with decoupled amplitude attenuation and phase dispersion terms.However,the nonphysical amplitude-compensation process will inevitably amplify the high-frequency noise in the wavefield in an exponential form,causing the numerical simulation to become unstable.This is due to the fact that the amplitude of the compensation grows exponentially with frequency.In order to achieve stable attenuation-compensated RTM,we modify the analytic expression of the attenuation compensation extrapolation operator and make it only compensate for amplitude loss within the effective frequency band.Based on this modified analytic formula,we then derive an explicit time-space domain attenuation compensation extrapolation operator.Finally,the implementation procedure of stable attenuation-compensated RTM is presented.In addition to being simple to implement,the newly proposed attenuation-compensated extrapolation operator is superior to the conventional low-pass filter in suppressing random noise,which will further improve the imaging resolution.We use two synthetic and one land seismic datasets to verify the stability and effectiveness of the proposed attenuationcompensated RTM in improving imaging resolution in viscous media. 展开更多
关键词 Seismic attenuation reverse time migration Stability strategy Pseudospectral method
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High-performance vertical GaN field-effect transistor with an integrated self-adapted channel diode for reverse conduction
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作者 邓思宇 廖德尊 +3 位作者 魏杰 张成 孙涛 罗小蓉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期570-576,共7页
A vertical GaN field-effect transistor with an integrated self-adapted channel diode(CD-FET)is proposed to improve the reverse conduction performance.It features a channel diode(CD)formed between a trench source on th... A vertical GaN field-effect transistor with an integrated self-adapted channel diode(CD-FET)is proposed to improve the reverse conduction performance.It features a channel diode(CD)formed between a trench source on the insulator and a P-type barrier layer(PBL),together with a P-shield layer under the trench gate.At forward conduction,the CD is pinched off due to depletion effects caused by both the PBL and the metal-insulator-semiconductor structure from the trench source,without influencing the on-state characteristic of the CD-FET.At reverse conduction,the depletion region narrows and thus the CD turns on to achieve a very low turn-on voltage(V_(F)),preventing the inherent body diode from turning on.Meanwhile,the PBL and P-shield layer can modulate the electric field distribution to improve the off-state breakdown voltage(BV).Moreover,the P-shield not only shields the gate from a high electric field but also transforms part of C_(GD)to CGS so as to significantly reduce the gate charge(Q_(GD)),leading to a low switching loss(E_(switch)).Consequently,the proposed CD-FET achieves a low V_(F)of 1.65 V and a high BV of 1446 V,and V_(F),Q_(GD)and E_(switch)of the CD-FET are decreased by 49%,55%and 80%,respectively,compared with those of a conventional metal-oxide-semiconductor field-effect transistor(MOSFET). 展开更多
关键词 GaN field effect transistor reverse conduction integrated diode turn-on voltage
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A Whale Optimization Algorithm with Distributed Collaboration and Reverse Learning Ability
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作者 Zhedong Xu Yongbo Su +1 位作者 Fang Yang Ming Zhang 《Computers, Materials & Continua》 SCIE EI 2023年第6期5965-5986,共22页
Due to the development of digital transformation,intelligent algorithms are getting more and more attention.The whale optimization algorithm(WOA)is one of swarm intelligence optimization algorithms and is widely used ... Due to the development of digital transformation,intelligent algorithms are getting more and more attention.The whale optimization algorithm(WOA)is one of swarm intelligence optimization algorithms and is widely used to solve practical engineering optimization problems.However,with the increased dimensions,higher requirements are put forward for algorithm performance.The double population whale optimization algorithm with distributed collaboration and reverse learning ability(DCRWOA)is proposed to solve the slow convergence speed and unstable search accuracy of the WOA algorithm in optimization problems.In the DCRWOA algorithm,the novel double population search strategy is constructed.Meanwhile,the reverse learning strategy is adopted in the population search process to help individuals quickly jump out of the non-ideal search area.Numerical experi-ments are carried out using standard test functions with different dimensions(10,50,100,200).The optimization case of shield construction parameters is also used to test the practical application performance of the proposed algo-rithm.The results show that the DCRWOA algorithm has higher optimization accuracy and stability,and the convergence speed is significantly improved.Therefore,the proposed DCRWOA algorithm provides a better method for solving practical optimization problems. 展开更多
关键词 Whale optimization algorithm double population cooperation DISTRIBUTION reverse learning convergence speed
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REVERSE CARLESON MEASURES ON GENERALIZED FOCK SPACES
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作者 曹广福 何莉 张艺渊 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期655-667,共13页
In this paper,we characterize reverse Carleson measures for a class of generalized Fock spaces F^(p)_(φ),with 0<p<∞and withφsatisfying dd^(c)_(φ)■ω0.As an application of these results,we obtain several equ... In this paper,we characterize reverse Carleson measures for a class of generalized Fock spaces F^(p)_(φ),with 0<p<∞and withφsatisfying dd^(c)_(φ)■ω0.As an application of these results,we obtain several equivalent characterizations for invertible Toeplitz operators Tψ,induced by positive bounded symbols φ on F^(2)_(φ). 展开更多
关键词 reverse Carleson measures invertible Toeplitz operators generalized Fock spaces
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Feature-Based Augmentation in Sarcasm Detection Using Reverse Generative Adversarial Network
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作者 Derwin Suhartono Alif Tri Handoyo Franz Adeta Junior 《Computers, Materials & Continua》 SCIE EI 2023年第12期3637-3657,共21页
Sarcasm detection in text data is an increasingly vital area of research due to the prevalence of sarcastic content in online communication.This study addresses challenges associated with small datasets and class imba... Sarcasm detection in text data is an increasingly vital area of research due to the prevalence of sarcastic content in online communication.This study addresses challenges associated with small datasets and class imbalances in sarcasm detection by employing comprehensive data pre-processing and Generative Adversial Network(GAN)based augmentation on diverse datasets,including iSarcasm,SemEval-18,and Ghosh.This research offers a novel pipeline for augmenting sarcasm data with Reverse Generative Adversarial Network(RGAN).The proposed RGAN method works by inverting labels between original and synthetic data during the training process.This inversion of labels provides feedback to the generator for generating high-quality data closely resembling the original distribution.Notably,the proposed RGAN model exhibits performance on par with standard GAN,showcasing its robust efficacy in augmenting text data.The exploration of various datasets highlights the nuanced impact of augmentation on model performance,with cautionary insights into maintaining a delicate balance between synthetic and original data.The methodological framework encompasses comprehensive data pre-processing and GAN-based augmentation,with a meticulous comparison against Natural Language Processing Augmentation(NLPAug)as an alternative augmentation technique.Overall,the F1-score of our proposed technique outperforms that of the synonym replacement augmentation technique using NLPAug.The increase in F1-score in experiments using RGAN ranged from 0.066%to 1.054%,and the use of standard GAN resulted in a 2.88%increase in F1-score.The proposed RGAN model outperformed the NLPAug method and demonstrated comparable performance to standard GAN,emphasizing its efficacy in text data augmentation. 展开更多
关键词 Data augmentation Generative Adversarial Network(GAN) reverse GAN(RGAN) sarcasm detection
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Research Progress of Reverse Monte Carlo and Its Application in Josephson Junction Barrier Layer
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作者 Junling Qiu Huihui Sun Shuya Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2077-2109,共33页
As indispensable components of superconducting circuit-based quantum computers,Josephson junctions determine how well superconducting qubits perform.Reverse Monte Carlo(RMC)can be used to recreate Josephson junction’... As indispensable components of superconducting circuit-based quantum computers,Josephson junctions determine how well superconducting qubits perform.Reverse Monte Carlo(RMC)can be used to recreate Josephson junction’s atomic structure based on experimental data,and the impact of the structure on junctions’properties can be investigated by combining different analysis techniques.In order to build a physical model of the atomic structure and then analyze the factors that affect its performance,this paper briefly reviews the development and evolution of the RMC algorithm.It also summarizes the modeling process and structural feature analysis of the Josephson junction in combination with different feature extraction techniques for electrical characterization devices.Additionally,the obstacles and potential directions of Josephson junction modeling,which serves as the theoretical foundation for the production of superconducting quantum devices at the atomic level,are discussed. 展开更多
关键词 reverse Monte Carlo Josephson junction alumina barrier layer
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