Modulating the electronic structure of a photocatalyst and constructing spatially separated redox sites are key strategies for achieving the photocatalytic dual-channel generation of H_(2)O_(2).In this study,a graphen...Modulating the electronic structure of a photocatalyst and constructing spatially separated redox sites are key strategies for achieving the photocatalytic dual-channel generation of H_(2)O_(2).In this study,a graphene-modified non-compensated Cu/N-co-doped titanium dioxide(Cu-N-TiO_(2)/rGO)photocatalyst was designed for the efficient synthesis of H_(2)O_(2) via a dual-channel pathway.Precise modulation of the TiO_(2) conduction band position was achieved through the synergistic coupling of Cu 3d orbitals hybridized with Ti 3d orbitals and hybridization of N 2p orbitals with O 2p orbitals.This approach significantly improved the utilization of sunlight while satisfying the redox potential requirements.Cu doping not only promoted the formation of oxygen vacancies but also reduced the formation of Ti^(3+)ions,the photogenerated charge recombination centers.The non-compensated doping of N effectively increased the solubility of Cu^(2+)ions in the titanium dioxide lattice,enhanced the adsorption of hydroxyl radical intermediates,and created conditions for the subsequent hydroxyl radical combinations promoting the generation of H_(2)O_(2).In addition,the introduction of highly conductive graphene improved the interfacial carrier separation efficiency while realizing the spatial separation of redox sites,creating conditions for dual-channel reactions.The experimental results showed that the H_(2)O_(2) yield of Cu-N-TiO_(2)/rGO under simulated sunlight reached 1266.7μmol/L,which was 25.2 times higher than that of pristine TiO_(2).This study elucidated the synergistic mechanism of the energy band structure modulation and interfacial optimization,which provided a new idea for the design of dual-channel H_(2)O_(2) production photocatalysts.展开更多
Driven by pulse modulated radio-frequency plasma in capacitively coupled discharge are studied by source, the behavior of SiH4/N2/02 using a one-dimensional fluid model. Totally, 48 different species （electrons, ions...Driven by pulse modulated radio-frequency plasma in capacitively coupled discharge are studied by source, the behavior of SiH4/N2/02 using a one-dimensional fluid model. Totally, 48 different species （electrons, ions, neutrals, radicals and excited species） are involved in this simulation. Time evolution of the particle densities and electron temperature with different duty cycles are obtained, as well as the electronegativity nsiH-3 /ne of the main negative ion （Sill3 ）. The results show that, by reducing the duty cycle, higher electron temperature and particle density can be achieved for the same average dissipated power, and the ion energy can also be effectively reduced, which will offer evident improvement in plasma deposition processes compared with the case of continuous wave discharge.展开更多
N2O is a significant atmospheric greenhouse gas that contributes to global warming and climate change.In this work,the high sensitivity detection of atmospheric N2O is achieved using wavelength modulation spectroscopy...N2O is a significant atmospheric greenhouse gas that contributes to global warming and climate change.In this work,the high sensitivity detection of atmospheric N2O is achieved using wavelength modulation spectroscopy(WMS)with an inter-band cascade laser operating around 3.939μm.A Lab VIEW-based software signal generator and software lock-in amplifiers are designed to simplify the system.In order to eliminate the interference from water vapor,the detection was performed at a pressure of 0.1 atm(1 atm=1.01325×10^5 Pa)and a drying tube was added to the system.To improve the system performance for long term detection,a novel frequency locking method and 2 f/1 f calibration-free method were employed to lock the laser frequency and calibrate the power fluctuations,respectively.The Allan deviation analysis of the results indicates a detection limit of^20 ppb(1 ppb=1.81205μg/m3)for a 1 s integration time,and the optimal detection limit is^5 ppb for a 40-s integration time.展开更多
Accurate vehicle detection is essential for autonomous driving,traffic monitoring,and intelligent transportation systems.This paper presents an enhanced YOLOv8n model that incorporates the Ghost Module,Convolutional B...Accurate vehicle detection is essential for autonomous driving,traffic monitoring,and intelligent transportation systems.This paper presents an enhanced YOLOv8n model that incorporates the Ghost Module,Convolutional Block Attention Module(CBAM),and Deformable Convolutional Networks v2(DCNv2).The Ghost Module streamlines feature generation to reduce redundancy,CBAM applies channel and spatial attention to improve feature focus,and DCNv2 enables adaptability to geometric variations in vehicle shapes.These components work together to improve both accuracy and computational efficiency.Evaluated on the KITTI dataset,the proposed model achieves 95.4%mAP@0.5—an 8.97% gain over standard YOLOv8n—along with 96.2% precision,93.7% recall,and a 94.93%F1-score.Comparative analysis with seven state-of-the-art detectors demonstrates consistent superiority in key performance metrics.An ablation study is also conducted to quantify the individual and combined contributions of GhostModule,CBAM,and DCNv2,highlighting their effectiveness in improving detection performance.By addressing feature redundancy,attention refinement,and spatial adaptability,the proposed model offers a robust and scalable solution for vehicle detection across diverse traffic scenarios.展开更多
In this paper,a class of non-weight modules over the N=2 super-BMS_(3)algebra g_(ε)are completely constructed.Denote the Ramond type algebra g_(0)and Neveu-Schwarz type algebra g_(1)by g_(R) and g_(NS),respectively.L...In this paper,a class of non-weight modules over the N=2 super-BMS_(3)algebra g_(ε)are completely constructed.Denote the Ramond type algebra g_(0)and Neveu-Schwarz type algebra g_(1)by g_(R) and g_(NS),respectively.Let L=C L_(0)⊕C P_(0)⊕C G+0⊕C G_(0)^(−)and H=CL_(0)⊕CP_(0)be the Cartan subalgebras of g_(R) and g_(NS),respectively,and let h=CL_(0)⊕CP_(0)⊕CG_(0)^(+)be the 3-dimensional subalgebra of L.These modules over g_(R) are free of rank 1 as modules of the subalgebra h,while these modules over g NS are free of rank 2 as modules of the Cartan subalgebra H.In fact,these modules are isomorphic and reducible.In particular,the non-trivial free U(ɧ)-modules of rank 1 over g NS do not exist.From these modules,we give a complete classification of free U(ɧ)-modules of rank 1 over g_(R) and free U(ɧ)-modules of rank 2 over g NS separately.展开更多
The topological N=2 superconformal algebra was introduced by Dijkgraaf,Verlinde and Verlinde as the symmetry algebra of topological strings at d<1.We give a classification of irreducible Z×Z-graded modules of ...The topological N=2 superconformal algebra was introduced by Dijkgraaf,Verlinde and Verlinde as the symmetry algebra of topological strings at d<1.We give a classification of irreducible Z×Z-graded modules of the intermediate series over this infinite-dimensional Lie superalgebra.展开更多
由于IEEE802.15.6协议规定了在不同数据速率下,BAN物理层采用不同的调制方式,为此,文章以其为基础,提出一种基于查找表的联合调制算法。该算法通过分析π/2-DBPSK和π/4-DQPSK的原理,以合并查找表的方式实现两种调制方式的统一。最后,利...由于IEEE802.15.6协议规定了在不同数据速率下,BAN物理层采用不同的调制方式,为此,文章以其为基础,提出一种基于查找表的联合调制算法。该算法通过分析π/2-DBPSK和π/4-DQPSK的原理,以合并查找表的方式实现两种调制方式的统一。最后,利用Model Sim SE 10.1b对算法进行了逻辑功能验证,并编写Verilog硬件描述代码进行了FPGA的板级验证。展开更多
This paper proposes a sigma-delta fractional-N frequency synthesizer-based multi-standard I/Q carrier generation system.With reasonable frequency planning,the system can be used in multi-standard wireless communicatio...This paper proposes a sigma-delta fractional-N frequency synthesizer-based multi-standard I/Q carrier generation system.With reasonable frequency planning,the system can be used in multi-standard wireless communication applications（GSM,WCDMA,GPRS,TD-SCDMA,WLAN（802.11a/b/g））.The implementation is achieved by a 0.13μm RF CMOS process.The measured results demonstrate that three quadrature VCOs（QVCO） continuously cover the frequency from 3.1 to 6.1 GHz（65.2%）,and through the successive divide-by-2 prescalers to achieve the frequency from 0.75 to 6.1 GHz continuously.The chip was fully integrated with the exception of an off-chip filter.The entire chip area is only 3.78 mm^2,and the system consumes a 21.7 mA@1.2 V supply without output buffers.The lock-in time of the PLL frequency synthesizer is less than 4μs over the entire frequency range with a direct frequency presetting technique and the auxiliary non-volatile memory（NVM）can store the digital configuration signal of the system,including presetting signals to avoid the calibration process case by case.展开更多
文摘Modulating the electronic structure of a photocatalyst and constructing spatially separated redox sites are key strategies for achieving the photocatalytic dual-channel generation of H_(2)O_(2).In this study,a graphene-modified non-compensated Cu/N-co-doped titanium dioxide(Cu-N-TiO_(2)/rGO)photocatalyst was designed for the efficient synthesis of H_(2)O_(2) via a dual-channel pathway.Precise modulation of the TiO_(2) conduction band position was achieved through the synergistic coupling of Cu 3d orbitals hybridized with Ti 3d orbitals and hybridization of N 2p orbitals with O 2p orbitals.This approach significantly improved the utilization of sunlight while satisfying the redox potential requirements.Cu doping not only promoted the formation of oxygen vacancies but also reduced the formation of Ti^(3+)ions,the photogenerated charge recombination centers.The non-compensated doping of N effectively increased the solubility of Cu^(2+)ions in the titanium dioxide lattice,enhanced the adsorption of hydroxyl radical intermediates,and created conditions for the subsequent hydroxyl radical combinations promoting the generation of H_(2)O_(2).In addition,the introduction of highly conductive graphene improved the interfacial carrier separation efficiency while realizing the spatial separation of redox sites,creating conditions for dual-channel reactions.The experimental results showed that the H_(2)O_(2) yield of Cu-N-TiO_(2)/rGO under simulated sunlight reached 1266.7μmol/L,which was 25.2 times higher than that of pristine TiO_(2).This study elucidated the synergistic mechanism of the energy band structure modulation and interfacial optimization,which provided a new idea for the design of dual-channel H_(2)O_(2) production photocatalysts.
基金supported by National Natural Science Foundation of China (No.10775025)Important National Science & Technology Specific Project of China (No.2011ZX02403-001)Program for New Century Excellent Talents in University of China (NCET-08-0073)
文摘Driven by pulse modulated radio-frequency plasma in capacitively coupled discharge are studied by source, the behavior of SiH4/N2/02 using a one-dimensional fluid model. Totally, 48 different species （electrons, ions, neutrals, radicals and excited species） are involved in this simulation. Time evolution of the particle densities and electron temperature with different duty cycles are obtained, as well as the electronegativity nsiH-3 /ne of the main negative ion （Sill3 ）. The results show that, by reducing the duty cycle, higher electron temperature and particle density can be achieved for the same average dissipated power, and the ion energy can also be effectively reduced, which will offer evident improvement in plasma deposition processes compared with the case of continuous wave discharge.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2018YFC021330404,2017YFC0209703,and2016TFC0303900)
文摘N2O is a significant atmospheric greenhouse gas that contributes to global warming and climate change.In this work,the high sensitivity detection of atmospheric N2O is achieved using wavelength modulation spectroscopy(WMS)with an inter-band cascade laser operating around 3.939μm.A Lab VIEW-based software signal generator and software lock-in amplifiers are designed to simplify the system.In order to eliminate the interference from water vapor,the detection was performed at a pressure of 0.1 atm(1 atm=1.01325×10^5 Pa)and a drying tube was added to the system.To improve the system performance for long term detection,a novel frequency locking method and 2 f/1 f calibration-free method were employed to lock the laser frequency and calibrate the power fluctuations,respectively.The Allan deviation analysis of the results indicates a detection limit of^20 ppb(1 ppb=1.81205μg/m3)for a 1 s integration time,and the optimal detection limit is^5 ppb for a 40-s integration time.
文摘Accurate vehicle detection is essential for autonomous driving,traffic monitoring,and intelligent transportation systems.This paper presents an enhanced YOLOv8n model that incorporates the Ghost Module,Convolutional Block Attention Module(CBAM),and Deformable Convolutional Networks v2(DCNv2).The Ghost Module streamlines feature generation to reduce redundancy,CBAM applies channel and spatial attention to improve feature focus,and DCNv2 enables adaptability to geometric variations in vehicle shapes.These components work together to improve both accuracy and computational efficiency.Evaluated on the KITTI dataset,the proposed model achieves 95.4%mAP@0.5—an 8.97% gain over standard YOLOv8n—along with 96.2% precision,93.7% recall,and a 94.93%F1-score.Comparative analysis with seven state-of-the-art detectors demonstrates consistent superiority in key performance metrics.An ablation study is also conducted to quantify the individual and combined contributions of GhostModule,CBAM,and DCNv2,highlighting their effectiveness in improving detection performance.By addressing feature redundancy,attention refinement,and spatial adaptability,the proposed model offers a robust and scalable solution for vehicle detection across diverse traffic scenarios.
基金the support of National Natural Science Foundation of China(Nos.12071276,11931009 and 12226402)Science and Technology Commission of Shanghai Municipality(No.25ZR1401126)+1 种基金the support of National Natural Science Foundation of China(Nos.11871325 and 12271332)Shanghai Natural Science Foundation grant(No.22ZR1424600).
文摘In this paper,a class of non-weight modules over the N=2 super-BMS_(3)algebra g_(ε)are completely constructed.Denote the Ramond type algebra g_(0)and Neveu-Schwarz type algebra g_(1)by g_(R) and g_(NS),respectively.Let L=C L_(0)⊕C P_(0)⊕C G+0⊕C G_(0)^(−)and H=CL_(0)⊕CP_(0)be the Cartan subalgebras of g_(R) and g_(NS),respectively,and let h=CL_(0)⊕CP_(0)⊕CG_(0)^(+)be the 3-dimensional subalgebra of L.These modules over g_(R) are free of rank 1 as modules of the subalgebra h,while these modules over g NS are free of rank 2 as modules of the Cartan subalgebra H.In fact,these modules are isomorphic and reducible.In particular,the non-trivial free U(ɧ)-modules of rank 1 over g NS do not exist.From these modules,we give a complete classification of free U(ɧ)-modules of rank 1 over g_(R) and free U(ɧ)-modules of rank 2 over g NS separately.
基金supported by the National Natural Science Foundation of China(Grant Nos.11771279,11661063,11671247,11801363,11931009)the Natural Science Foundation of Shanghai(Grant No.16ZR1415000)the Fundamental Research Funds for the Central Universities(Grant No.JZ2019HGTB0056).
文摘The topological N=2 superconformal algebra was introduced by Dijkgraaf,Verlinde and Verlinde as the symmetry algebra of topological strings at d<1.We give a classification of irreducible Z×Z-graded modules of the intermediate series over this infinite-dimensional Lie superalgebra.
文摘由于IEEE802.15.6协议规定了在不同数据速率下,BAN物理层采用不同的调制方式,为此,文章以其为基础,提出一种基于查找表的联合调制算法。该算法通过分析π/2-DBPSK和π/4-DQPSK的原理,以合并查找表的方式实现两种调制方式的统一。最后,利用Model Sim SE 10.1b对算法进行了逻辑功能验证,并编写Verilog硬件描述代码进行了FPGA的板级验证。
基金Project supported by the Chinese National High-Tech Research and Development Program(Nos2009ZX03007-001,2009AA011606)the National Natural Science Foundation of China(No60976023)
文摘This paper proposes a sigma-delta fractional-N frequency synthesizer-based multi-standard I/Q carrier generation system.With reasonable frequency planning,the system can be used in multi-standard wireless communication applications（GSM,WCDMA,GPRS,TD-SCDMA,WLAN（802.11a/b/g））.The implementation is achieved by a 0.13μm RF CMOS process.The measured results demonstrate that three quadrature VCOs（QVCO） continuously cover the frequency from 3.1 to 6.1 GHz（65.2%）,and through the successive divide-by-2 prescalers to achieve the frequency from 0.75 to 6.1 GHz continuously.The chip was fully integrated with the exception of an off-chip filter.The entire chip area is only 3.78 mm^2,and the system consumes a 21.7 mA@1.2 V supply without output buffers.The lock-in time of the PLL frequency synthesizer is less than 4μs over the entire frequency range with a direct frequency presetting technique and the auxiliary non-volatile memory（NVM）can store the digital configuration signal of the system,including presetting signals to avoid the calibration process case by case.
