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Optimization Design for the Sandwich Piezoelectric Transmitters in Acoustic Logging 认领 引用 被引量：2
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作者 魏倩 王秀明 +1 位作者 车承轩 丛健生 《Chinese Physics Letters》 SCIE EI CAS CSCD 2016年第7期102-104,共3页
An optimized transducer prototype with a sandwich structure vibrated longitudinally is proposed for a transmitter in acoustic logging, especially in acoustic logging while drilling, 5y taking account of drilling envir... An optimized transducer prototype with a sandwich structure vibrated longitudinally is proposed for a transmitter in acoustic logging, especially in acoustic logging while drilling, 5y taking account of drilling environments with high temperature and pressure, as well as strong collar drilling vibration during the drilling process. Aimed to improve the transmitting performance, numerical and experimental studies for the transducer optimization are conducted. The impact of location and length of the piezoelectric stack on resonance characteristics arid effective electromeehanical coupling coefficient is calculated and analyzed. Admittance and transmitting performance of the proposed transducer are measured in laboratory experiments, and the results are compared with simulated ones. It is shown that the newly proposed transducer has higher transmitting performance with lower resonance frequencies. This work provides theoretical and experimental bases for transducer designing and acoustic wave measurements in acoustic logging, especially in acoustic logging while drilling. 展开更多
关键词 of on in Optimization Design for the Sandwich Piezoelectric Transmitters in Acoustic Logging is for
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High Power RF Transmitters for ICRF Applications on EAST 认领 引用 被引量：3
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作者 毛玉周 袁帅 +9 位作者 赵燕平 张新军 陈根 R.KUMAZAWA 程艳 王磊 琚松青 邓旭 秦成明 杨磊 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第3期261-265,共5页
An Ion Cyclotron Range of Frequency （ICRF） system with a radio frequency （RF） power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak （EAST）. High RF power transmitters were de... An Ion Cyclotron Range of Frequency （ICRF） system with a radio frequency （RF） power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak （EAST）. High RF power transmitters were designed as a part of the research and development （R^D） for an ICRF system with long pulse operation at megawatt levels in a frequency range of 25 MHz to 70 MHz. Studies presented in this paper cover the following parts of the high power transmitter： the three staged high power amplifier, which is composed of a 5 kW wide- band solid state amplifier, a 100 kW tetrode drive stage amplifier and a 1.5 MW tetrode final stage amplifier, and the DC high voltage power supply （HVPS）. Based on engineering design and static examinations, the RF transmitters were tested using a matched dummy load where an RF output power of 1.5 MW was achieved. The transmitters provide 6 MW RF power in primary phase and will reach a level up to 12 MW after a later upgrade. The transmitters performed successfully in stable operations in EAST and HT-7 devices. Up to 1.8 MW of RF power was injected into plasmas in EAST ICRF heating experiments during the 2010 autumn campaign and plasma performance was greatly improved. 展开更多
关键词 power amplifier RF transmitter ICRF system EAST
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Sutureless Implantation of Acoustic Transmitters in Rainbow Trout Exceeding 2% Tag-to-Body Ratio 认领 引用
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作者 Ashley Kelican Nathan Huysman +1 位作者 Jill M. Voorhees Michael E. Barnes 《Advances in Bioscience and Biotechnology》 CAS 2022年第6期265-271,共7页
A novel sutureless surgical technique has been successfully used to implant acoustic transmitters in relatively large rainbow trout Oncorhynchus mykiss with a tag-to-body-ratio of 0.88%. This study examined the same t... A novel sutureless surgical technique has been successfully used to implant acoustic transmitters in relatively large rainbow trout Oncorhynchus mykiss with a tag-to-body-ratio of 0.88%. This study examined the same technique in smaller rainbow trout in two, 12-week trials comparing both sutured and sutureless surgical techniques. In the first trial using a tag-to-body-ratio of 1.9% ± 0.04%, tag retention was only 16.6% in fish without sutures, which was significantly lower than the 83.3% retention with sutured incisions. Similarly, in the second trial with a tag-to-body-ratio of 3.2% ± 0.03%, tag retention was 55.5% without sutures, which was significantly lower than the 90.0% retention using sutures. Mortality was not significantly different between treatments in either trial. The results of this study indicate that sutures must be used during surgeries to implant acoustic transmitters in relatively smaller fish with tag-to-body-ratios at or above 1.9%. 展开更多
关键词 Rainbow Trout Oncorhynchus mykiss Surgery Acoustic Transmitter
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EFFECTS OF MOXIBUSTION ON THE IMMUNITY AND THE CENTRAL NERVOUS TRANSMITTERS IN MICE WITH YANG DEFICIENCY 认领 引用
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作者 宋小鸽 唐照亮 +4 位作者 侯正明 陈全珠 袁静 章复清 朱舜丽 《World Journal of Acupuncture-Moxibustion》 CAS 1999年第4期47-50,共4页
In the present paper, the effects of moxibustion on the immune organs, on the multiplication reactivity of the splenic lymphocyte and the reactivity to the IL - 2, and on the transmitters in brain tissues of the mice ... In the present paper, the effects of moxibustion on the immune organs, on the multiplication reactivity of the splenic lymphocyte and the reactivity to the IL - 2, and on the transmitters in brain tissues of the mice with "yang deficiency" were studied. 30 mice were randomly divided into three groups: the normal group, the peng deficiency control group and the moxibustion treated group. Our study found out that in the mice of yang deficienly, the atrophy of the immunt organs was prevented, the reactivity of the splenocyte and the reactivity to IL - 2 were heightened, the amounts of the DA, NE and E in brain were increased significantly after moxibustion on the Point Shengshu. It can be held that moxibustion may protect the immune organs and regulate the immunity of the mouse with yang deficienly, and the effects may be contributed to the increase of the nervous transmitters in the brain. 展开更多
关键词 Immunity Central nervous transmitter Moxibustion Yang deficiency
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Lightning Protection Measures for TV Transmitters at High Mountain Transmitting Stations 认领 引用
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作者 HU Guocai HUANG Liangliang 《外文科技期刊数据库（文摘版）自然科学》 2021年第12期068-070,共3页
With the rapid development of science and technology, radio and television are becoming more and more popular. In addition, the continuous improvement of people's spiritual and cultural enthusiasm puts forward hig... With the rapid development of science and technology, radio and television are becoming more and more popular. In addition, the continuous improvement of people's spiritual and cultural enthusiasm puts forward higher requirements for radio and television. In order to ensure signal coverage, most radio and television stations choose high mountains. There are some problems and shortcomings when starting the mountain station. The integrity, integrity and reliability of radio station facilities and equipment depend on the security of transmissions and broadcasts. In order to ensure the safety and high-quality transmission of broadcast signals, the daily safety management of equipment in the computer room is very important. 展开更多
关键词 high mountain launch station television transmitter lightning protection
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Artificial modification of Earth's radiation belts by ground-based very-low-frequency(VLF)transmitters 认领 引用 被引量：15
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作者 Binbin NI Man HUA +4 位作者 Xudong GU Song FU Zheng XIANG Xing CAO Xin MA 《Science China Earth Sciences》 SCIE EI CAS CSCD 2022年第3期391-413,共23页
Wave-particle interactions play a fundamental role in the dynamic variability of Earth’s donut-shaped radiation belts that are highly populated by magnetically trapped energetic particles and characteristically separ... Wave-particle interactions play a fundamental role in the dynamic variability of Earth’s donut-shaped radiation belts that are highly populated by magnetically trapped energetic particles and characteristically separated by the slot devoid of high energetic electrons.Owing to the continuous accumulation of high-quality wave and particle measurements from multiple satellites in geospace,the important contribution of ground-based very-low-frequency(VLF)transmitter waves to the electron dynamics in the near-Earth space has been unprecedently advanced,in addition to those established findings of the significant effects of a variety of naturally occurring magnetospheric waves.This paper focuses on the artificial modification of Earth’s inner radiation belt and slot by artificial VLF transmitter emissions.We review the global distributions of VLF transmitter waves in geospace,their scattering effects on radiation belt electrons in terms of both theoretical and observational analyses,and diffusion simulation results of wave-particle interactions along with data-model comparisons.We start with a brief review of the radiation belt electron dynamics and an introduction of anthropogenic VLF transmitter waves.Subsequently,we review the global morphology of in situ VLF transmitter waves corresponding to different transmitter locations,including their day-night asymmetry,geographic distributions,seasonal and geomagnetic activity dependence,and wave propagation features.Existed theoretical and observational analyses of electron scattering effects by VLF transmitter waves are then reviewed to approach the underlying physics that can modulate the spatio-temporal variations of the electron radiation belts.Further Fokker-Planck electron diffusion simulations and their comparisons with realistic satellite observations clearly indicate that VLF transmitter emissions can effectively remove energetic electrons to produce a radially bifurcated electron belt,thereby quantitatively confirming the direct link between operations of VLF transmitters at ground and changes of the energetic electron environment in space.We finally discuss the unsolved problems and possible future research in this area,which has important implications for potential mitigation of the natural particle radiation environment with active means. 展开更多
关键词 VLF transmitters Wave-particle interactions Electron precipitation Earth’s radiation belts Flux bifurcation
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Mid-Infrared Light Exhibits Tissue-Specific Transmittance and Modulates Neural Signal Conduction Along Axons 认领 引用
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作者 Xi Liu Zhuoyi Wang +3 位作者 Zhi Qiao Yujie Xiao Hui Guo Yousheng Shu 《Neuroscience Bulletin》 SCIE CAS CSCD 2026年第7期1459-1472,共14页
Non-invasive infrared(IR)modulation requires IR photons to penetrate multi-layered cranial barriers,including skin,skull bone,and dura mater.However,the wavelength-dependent transmittance profiles and the modulatory e... Non-invasive infrared(IR)modulation requires IR photons to penetrate multi-layered cranial barriers,including skin,skull bone,and dura mater.However,the wavelength-dependent transmittance profiles and the modulatory effect of IR light on neural signals remain poorly understood.Using synchrotron radiation Fourier-transform infrared(SR-FTIR)microspectroscopy,we systematically mapped transmittance spectra of freshly isolated cranial tissue layers and brain tissues(gray matter and white matter)obtained from adult mice.The viability of brain tissue was maintained through microfluidic and oxygenated artificial cerebrospinal fluid(ACSF)perfusion during spectral acquisition.We identified two IR windows with relatively high transmittance through cranial tissues:a near-infrared(NIR)window(wavelength:1.5–3.0μm)and a mid-infrared(MIR)window(3.5–6.0μm).Notably,the MIR sub-band ranging from 5.2 to 5.7μm exhibited a relatively higher transmittance through neural tissue,particularly in axon bundles,compared to the surrounding bath solution.Further electrophysiological experiments revealed that MIR with a wavelength of 5.6μm substantially decreased the amplitude and duration of both somatic and axonal action potentials,while simultaneously facilitating their conduction velocity along both myelinated and unmyelinated axons.Together,these results identify specific IR bands that can penetrate the cranial tissue layers and reveal a wavelength-specific modulation of neural signals,providing a promising non-invasive strategy for IR neuromodulation. 展开更多
关键词 Action potential Light transmittance Mid-infrared light Neuromodulation SR-FTIR
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Influence of silicon ion implantation on the morphological features,structural properties,optical,and electrical behavior of CR-39 polymers 认领 引用
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作者 Bashir S Ahmad S +3 位作者 Ali N Umm-i-Kalsoom Rafique M S Husinsky W 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第7期516-526,共11页
The variations in morphological features,structural properties,optical characteristics,and electrical behavior induced by 610-keV Si ions in the CR-39 matrix have been investigated in the current research work.Polymer... The variations in morphological features,structural properties,optical characteristics,and electrical behavior induced by 610-keV Si ions in the CR-39 matrix have been investigated in the current research work.Polymer targets were irradiated with Si ions for various fluences spanning from 5×1013ions/cm2 to 35×1016ions/cm2.The implantation of ions in the polymeric target generally leads to chain scission,bond breaking,and cross-linking,along with the formation of free radicals and ions.To confirm these effects,various characterization techniques have been utilized.Optical microscopy reveals the creation of micro-cavities and cracks along the grain boundaries.Confocal microscopy demonstrates the formation of micro-sized hillocks.The formation of SiC phase at 890 cm-1following ion implantation was identified by Raman spectroscopy.Furthermore,in CR-39,a significant reduction in optical transmittance in the visible region is attributable to the formation of Si and carbonaceous clusters on the target surface.The enhancement in the electrical conductivity of the Si ion implanted polymer with an increase in ion fluence is attributable to fine crystallinity and the development of SiC bridges.The assessed temperature of the surface of the implanted polymer ranges from 2.2×104K to 6.2×104K.The LET(total linear energy transfer)value of 610-keV implanted ions and their depth are 63 eV/Å and 1.11µm recorded in CR-39,respectively,estimated by SRIM simulation.The improved morphological features,structural properties,optical characteristics,and electrical behavior of CR-39 make it beneficial for applications in packaging and electronic industries,medical sciences,and photonic devices. 展开更多
关键词 surface morphology carbonaceous clusters optical transmittance structural modification
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Dual Transmitter Oscillations for Ejaculation 认领 引用
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作者 Anqi Wei Shuqin Zhan +3 位作者 Hong Fan Huadong Xu Xinjiang Kang Changhe Wang 《Neuroscience Bulletin》 SCIE CAS CSCD 2026年第1期251-253,共3页
Male sexual behaviors,including mounting,intromission,and ejaculation,are not only critical for reproduction but also serve as a model for understanding how the brain orchestrates sequential motor and motivational pro... Male sexual behaviors,including mounting,intromission,and ejaculation,are not only critical for reproduction but also serve as a model for understanding how the brain orchestrates sequential motor and motivational processes.While previous studies have identified key brain regions involved in sexual behaviors,such as the medial preoptic area(MPOA)and the nucleus accumbens(NAc)[14],the neural mechanisms governing the transitions between different phases of male sexual behavior remain poorly understood. 展开更多
关键词 brain regions neural mechanisms male sexual behaviorsincluding mounting intromission sexual behaviorssuch dual transmitter oscillations ejaculation
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Novel photonic packet WDM ring networks with tunable transmitters and fixed receivers using multi-token protocol 认领 引用
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作者 高志国 陈宏伟 +1 位作者 陈明华 谢世钟 《Chinese Optics Letters》 EI CAS 2005年第9期503-506,共4页
A kind of novel architecture of unslotted photonic packet switching wavelength division multiplexing （WDM） ring network with tunable transmitters and fixed receivers was proposed. In the network the wavelength was u... A kind of novel architecture of unslotted photonic packet switching wavelength division multiplexing （WDM） ring network with tunable transmitters and fixed receivers was proposed. In the network the wavelength was used as optical packet label and node media access controller （MAC） address. Optical packets transmitter was made up of tunable laser that was modulated at 10, 40 Gb/s or higher. Optical packet receiver was made up of Bragg grating, circulator, and fixed receiver. Used as metropolitan access network, it is shown through simulation how a multi-token MAC protocol can be implemented to avoid packet collision and achieve efficient bandwidth utilization. Packet delay, throughput, and packet dropping probability results are presented under uniform and none uniform Possion traffic. 展开更多
关键词 Bandwidth Fiber Bragg gratings Packet networks Packet switching Throughput Transmitters
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A study on the response of planting density to 3D plant shape plasticity and population light transmittance of maize 认领 引用 被引量：1
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作者 Guangtao Wang Guanmin Huang +6 位作者 Weiliang Wen Sheng Wu Xianju Lu Bo Chen Xinming Ma Xinyu Guo Chunjiang Zhao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2026年第8期3208-3217,共10页
Traditional two-dimensional(2D)analyses of maize(Zea mays L.)plant shape plasticity and canopy transmission under varying planting densities have limitations in capturing spatial heterogeneity.This study used a three-... Traditional two-dimensional(2D)analyses of maize(Zea mays L.)plant shape plasticity and canopy transmission under varying planting densities have limitations in capturing spatial heterogeneity.This study used a three-dimensional(3D)phenotyping platform to investigate architectural plasticity across different maize varieties and planting densities.Seven novel 3D architectural parameters were developed,and 3D canopy models were constructed for light distribution simulation.At the vegetative stage 9(V9)stage,medium planting density(67,500 plants ha-1,MD)increased plant side width and convex hull volume by 7.2 and 11.4%,respectively,compared to low planting density(37,500 plants ha-1,LD).High planting density(97,500 plants ha-1,HD)increased the width and volume by 4.2 and 17.8%,respectively,compared with MD.Similar changes were maintained at the V13 stage.At the silking stage,the number of voxel volume plant(NVP)and projected area(PJA)decreased by 6.2 and 11.9%,respectively,under MD compared with LD,and by 4.9 and 3.6%,respectively,under HD compared with MD.Across all densities,PJA and NVP in both MC812 and JNK728 were consistently lower than in ZD958.A bottom light transmittance estimation model combining point cloud parameters with support vector regression achieved reliable predictions(R2=0.76,RMSE=2.89%).The 3D canopy model effectively simulated population light distribution(R2=0.83,RMSE=8.53%).NVP and PJA were identified as critical parameters affecting bottom canopy transmittance,suggesting their potential as 3D selection indices for maize density tolerance breeding.These findings provide insights into stage-specific architectural plasticity and light interception,supporting molecular design breeding of density-tolerant maize. 展开更多
关键词 maize planting density 3D phenotyping light transmittance 3D canopy model
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Achieving Enhanced Optical Transparency and Low-dielectric Properties in Meta-substituted Copolyimides for Flexible Substrates 认领 引用
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作者 Zi-Yang Liu Yan-Yu Gao +3 位作者 Cheng Wang Qian-Qian Yu Zhi-Long Zhang Lin-Ge Wang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2026年第2期341-351,I0008,共11页
The development of high-performance transparent substrates is critical for next-generation flexible electronic devices.Herein,we designed two novel meta-substituted diamines incorporating trifluoromethyl(―CF3)and ... The development of high-performance transparent substrates is critical for next-generation flexible electronic devices.Herein,we designed two novel meta-substituted diamines incorporating trifluoromethyl(―CF3)and methyl(―CH3)groups to synthesize colorless copolyimide(CPI)films via copolymerization with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)/3,3′,4,4′-biphenyltetracarboxylic dianhydride(BPDA).The combination of meta-substituted architecture and substituents enables the simultaneous attainment of an ultralow dielectric constant(D_k)and high transparency.The meta-substitution geometry and electronic effects of―CF3/―CH3 effectively suppressed charge-transfer complex(CTC)formation,expanded fractional free volume(FFV),and restricted π-electron conjugation,as validated by DFT calculations and wide-angle X-ray diffraction(WAXD)analysis.The optimized CPI film(PIA1-6FDA/BPDA(10/0))achieved outstanding transmittance(T450=88.15%),ultralow dielectric constant(Dk=2.08 at 1 k Hz),and minimal dielectric loss(Df=0.0012),while maintaining robust thermal stability(Td5%>523℃)and mechanical strength(σ=87.5 MPa).This work establishes a molecular engineering strategy to concurrently enhance the optical and dielectric properties,positioning meta-substituted CPIs as promising candidates for transparent flexible devices. 展开更多
关键词 Colorless polyimide Meta-substitution Dielectric constant Optical transmittance Flexible electronics
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Semitransparent Perovskite Solar Cells:Strategies,Prospects,and Challenges 认领 引用
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作者 Mohamad Firdaus Mohamad Noh Nurul Affiqah Arzaee +6 位作者 Siti Naqiyah Sadikin Muhammad Idzdihar Idris Chien Fat Chau Boon Kar Yap Jingsong Huang Ryousuke Ishikawa Ahmad Wafi Mahmood Zuhdi 《Nano-Micro Letters》 SCIE EI CAS CSCD 2026年第9期563-628,共66页
Perovskite solar cells(PSCs)have achieved efficiencies comparable to established photovoltaic technologies,positioning them as strong contenders for next-generation solar energy systems.Amid these advances,research ef... Perovskite solar cells(PSCs)have achieved efficiencies comparable to established photovoltaic technologies,positioning them as strong contenders for next-generation solar energy systems.Amid these advances,research efforts are now directed toward extending PSCs functionality by combining efficient power generation with optical transparency,leading to the emergence of semitransparent PSCs(ST-PSCs).Advancing this technology requires deeper understanding of its design principles,applications,economic viability,and performance limitations.Therefore,this review examines key strategies for achieving an optimal balance between efficiency and optical transparency in ST-PSCs across small-,large-scale,and flexible devices,with emphasis on the functional roles and optimization approaches of individual components.Particular attention is devoted to stability challenges,including degradation mechanisms and recent strategies for improving their durability.The versatility of ST-PSCs is further illustrated through their integration into advanced architectures such as tandem and bifacial configurations,as well as broader applications including building-integrated photovoltaics,agrivoltaic systems,and photovoltaic–photoelectrochemical hybrids for hydrogen production.A technoeconomic perspective is also provided,with emphasis on manufacturing cost and levelized cost of electricity for ST-PSCs.Finally,the remaining challenges,particularly related to long-term stability,scalability,cost,and area constraints,are critically discussed,along with potential pathways toward commercial realization of ST-PSC technology. 展开更多
关键词 Semitransparent perovskite solar cells Light utilization efficiency Average transmittance Tandem Building-integrated photovoltaics
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Overcoming optical/electrical losses in ultra-thin PEDOT:PSS-based interconnecting layers for efficient tandem solar cells 认领 引用
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作者 Bing Guo Ruihan Wu +8 位作者 Senyao Wang Jiaqi Li Bin Kan Zhaoyang Yao Xiangjian Wan Chenxi Li Lei Meng Yongfang Li Yongsheng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2026年第4期151-158,I0005,共8页
The interconnecting layer(ICL) plays a critical role in series-connected tandem solar cells(TSCs).However,the PEDOT:PSS layer,commonly used hole transport layer in ICL,still exhibits non-negligible light absorption,wh... The interconnecting layer(ICL) plays a critical role in series-connected tandem solar cells(TSCs).However,the PEDOT:PSS layer,commonly used hole transport layer in ICL,still exhibits non-negligible light absorption,which remains an obstacle to further improve the photovoltaic performance of TSCs.Here,we demonstrate an efficient strategy to mitigate optical and electrical losses in PEDOT:PSS-based ICLs by reconstructing PEDOT:PSS film via alkali metal carbonate(AMC) doping.AMC doping can increase the proportion of PEDOT in PEDOT:PSS thin films,allowing them to be ultra-thin but robust enough to isolate adjacent active layers.Comprehensive characterizations demonstrate that AMC doping promote increased transmittance,decreased resistance and optimized surface morphology for PEDOT:PSS films.As a result,both the short-circuit current density(Jsc) and power conversion efficiency(PCE) are improved after AMC doping in PEDOT:PSS for TSCs with different active layer combinations,exhibiting excellent universality in TSCs application.Notably,the PCEs of organic homo-TSCs and perovskite/organic TSCs with AMC doping reached 20.04 % and 26.05 %,respectively.Our work underscores the great potential of AMC doping in optimizing PEDOT:PSS films in ICL,offering an innovative pathway for fabricating highly efficient TSCs. 展开更多
关键词 Tandem solar cells PEDOT:PSS Interconnecting layer Transmittance Doping
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High Throughput 3D Phenotyping of Canopy Occupation Volume as Major Predictor of Rice Canopy Photosynthesis 认领 引用
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作者 ZHOU Jiaren SONG Qingfeng +4 位作者 LI Wanwan ZHANG Mengqi ZHANG Man ZHU Xinguang WANG Minjuan 《Rice science》 SCIE CAS CSCD 2026年第1期99-112,I0074-I0080,共14页
Canopy photosynthesis,rather than leaf photosynthesis,is highly related to plant biomass and yield formation.Studying canopy photosynthesis and identifying the parameters that control it can help optimize agricultural... Canopy photosynthesis,rather than leaf photosynthesis,is highly related to plant biomass and yield formation.Studying canopy photosynthesis and identifying the parameters that control it can help optimize agricultural management and achieve crop yield potential.Compared with traditional parameters,canopy occupation volume(COV)offers an integrative parameter on canopy architecture related to canopy photosynthetic rates.In this study,we developed a high-throughput method to derive COV for different rice varieties.We first used multi-perspective two-dimensional imaging to reconstruct three-dimensional point clouds of rice plants and developed a suite of pipelines to calculate plant height,leaf number,tiller number,and biomass,with R2 values of 91.8%,95.9%,82.3%,and 94.3%,respectively.We further employed point cloud data to reconstruct the surfaces of rice plants and construct a virtual canopy model of the rice population.Light distribution was simulated using a ray-tracing algorithm and canopy photosynthetic rates were simulated via photosynthetic rate-incident light intensity curve fitting.Furthermore,we systematically explored the relationships between canopy phenotypes and photosynthetic rates,and found that COV was the most effective predictor of canopy photosynthesis,achieving an R2 value of 92.1%.Adjustment in atmospheric transmittance showed that COV strongly correlated with canopy photosynthesis under different light conditions,with higher accuracy observed under diffuse light.Variations in planting density confirmed that this correlation remained strong at the community level.In summary,this study demonstrates that COV is closely linked to simulated canopy photosynthesis and the developed pipeline can support future agronomic and breeding research. 展开更多
关键词 canopy phenomics canopy photosynthesis canopy occupation volume three-dimensional canopy rice ray-tracing algorithm atmospheric transmittance
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Mechanical design of off-axis antenna for laser transmitter integration device 认领 引用
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作者 Boxiang HOU Qimeng CHEN +3 位作者 Liang GAO Lei YANG Qiang SUN Keyan DONG 《Optoelectronics Letters》 EI 2026年第6期327-331,共5页
To ensure the stability of the laser communication system under complex dynamic loads,an off-axis dual-mirror optical antenna system was developed.Thermal-mechanical coupling analysis and wavefront aberration evaluati... To ensure the stability of the laser communication system under complex dynamic loads,an off-axis dual-mirror optical antenna system was developed.Thermal-mechanical coupling analysis and wavefront aberration evaluation were conducted to predict the aberration under dynamic conditions and verify structural reliability.Based on D'Alembert's principle,an acceleration-temperature gradient coupling model was constructed,and a mapping between rigid body displacement and wavefront error was established.Simulation results indicate that the maximum deformation under composite loading is 0.065873 mm,and the root-mean-square(RMS)wavefront error increases from 0.047λto 0.068λ,remaining within the RMS<0.1λdesign threshold.The initial wavefront RMS measured by the ZYGO interferometer is 0.052λ,deviating from the simulated value of 0.047λby only 0.005λ.This validates the model's accuracy and offers theoretical and engineering support for high-precision optical design in space-based laser communication systems. 展开更多
关键词 wavefront aberration evaluation verify structural reliabilitybased rigid body displacement laser communication system off axis antenna laser transmitter predict aberration dynamic conditions dalemberts principlean
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First demonstration of lithium niobate photonic chip for dense wavelength-division multiplexing transmitters 认领 引用 被引量：7
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作者 Hongxuan Liu Bingcheng Pan +4 位作者 Huan Li Zejie Yu Liu Liu Yaocheng Shi Daoxin Dai 《Advanced Photonics》 SCIE EI CAS CSCD 2024年第6期55-66,共12页
Modern optical communications rely heavily on dense wavelength-division multiplexing(DWDM)technology because of its capability of significantly increasing transmission channels.Here,we demonstrate,for the first time t... Modern optical communications rely heavily on dense wavelength-division multiplexing(DWDM)technology because of its capability of significantly increasing transmission channels.Here,we demonstrate,for the first time to the best of our knowledge,a compact photonic chip for DWDM transmitters on lithiumniobate-on-insulator(LNOI)by introducing the array of 2×2 Fabry–Perot(FP)cavity electro-optic(EO)modulators.A four-channel LNOI photonic chip for DWDM is designed and realized with a channel spacing of 1.6 nm(which is the narrowest one reported until now for LNOI optical transmitters),exhibiting a total excess loss of 1.3 dB and high 3-dB EO bandwidths of>67 GHz for all channels.Specifically,these four 2×2 FP cavities are designed with broadened LNOI photonic waveguides in the cavity sections,and they are placed very closely on the chip so that their resonance wavelengths are aligned precisely with the desired channelspacing of∼1.6 nm.Finally,the generation of 4×80-Gbps on–off keying and 4×100-Gbps PAM4 signals is demonstrated successfully with four channels,and the power consumption is as low as∼5.1 fJ∕bit.The present photonic chip has a compact footprint of about 0.78 mm×0.58 mm,showing great potential to work with more than four channels and to be very useful for future large-capacity optical links. 展开更多
关键词 lithium niobate dense wavelength-division multiplexing electro-optic modulator transmitter Fabry-Perot cavity
Ultra-compact lithium niobate photonic chip for high-capacity and energy-efficient wavelength-division-multiplexing transmitters 认领 引用 被引量：18
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作者 Hongxuan Liu Bingcheng Pan +6 位作者 Yishu Huang Jianghao He Ming Zhang Zejie Yu Liu Liu Yaocheng Shi Daoxin Dai 《Light: Advanced Manufacturing》 2023年第2期57-66,共10页
Recently,high-performance thin-film lithium niobate optical modulators have emerged that,together with advanced multiplexing technologies,are highly expected to satisfy the ever-growing demand for high-capacity optica... Recently,high-performance thin-film lithium niobate optical modulators have emerged that,together with advanced multiplexing technologies,are highly expected to satisfy the ever-growing demand for high-capacity optical interconnects utilizing multiple channels.Accordingly,in this study,a compact lithium-niobate-on-insulator(LNOI)photonic chip was adopted to establish four-channel wavelength-division-multiplexing(WDM)transmitters,comprising four optical modulators based on ultracompact 2×2 Fabry-Perot cavities and a four-channel WDM filter based on multimode waveguide gratings.The fabricated chip with four wavelength channels has a total footprint as compact as 0.3×2.8 mm2,and exhibits an excess loss of~0.8 dB as well as low inter-channel crosstalk of<–22 dB.Using this LNOI photonic chip,high-capacity data transmissions of 320 Gbps(4×80 Gbps)on-off-keying signals and 400 Gbps(4×100 Gbps)four-level pulse amplitude signals were successfully realized with the ultra-low power consumption of 11.9 fJ/bit. 展开更多
关键词 Lithium niobate on insulator Fabry-Perot cavity Electro-optic Transmitter Wavelength-division multiplexing
Low-subrate sparse reconstruction with threshold-adaptive denoising and basis learning for infrared aerial imagery 认领 引用
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作者 Maoji QIU Hao LIU 《Optoelectronics Letters》 EI 2026年第2期98-104,共7页
Due to the property of infrared aerial imagery, the local prior is sufficient especially for low-subrate block compressive sensing(BCS) reconstruction of infrared aerial images, while its complexity is much lower than... Due to the property of infrared aerial imagery, the local prior is sufficient especially for low-subrate block compressive sensing(BCS) reconstruction of infrared aerial images, while its complexity is much lower than nonlocal prior. The typical low-subrates can effectively improve the BCS transmission efficiency and reduce the burden of transmitter hardware. Therefore, this paper proposes a low-subrate sparse reconstruction algorithm with threshold-adaptive denoising and basis learning(TDBL), which adopts both split Bregman iteration(SBI) and adaptive threshold to implement the model-based BCS reconstruction for infrared aerial imagery. The experimental results show that as compared with the state-of-the-art algorithms, the proposed algorithm can obtain better recovery quality and less runtime on both HIT-UAV and M200-XT2 DroneVehicle datasets. the transmission efficiency and reduce the burden of transmitter hardware. The current NSS-guided reconstruction algorithms are trained and tested on natural image datasets by using relatively high subrates(more than 0.1). Due to significant difference in image contrast and pixel distribution between UAV infrared images and natural images, the performance of these algorithms on UAV infrared image datasets may be difficult to meet expectations. In recent years, the improvement of BCS recovery quality is not obvious with very high complexity, where the core step is to build a suitable dictionary, and then solve the associated sparsity of the dictionary. Previous BCS algorithms usually utilize the special iterative shrinkagehresholding(IST)[11] method to solve the l0 minimization problem. For BCS recovery quality and runtime of UAV infrared imagery, split Bregman iteration(SBI)[12] is a competitive mechanism, so we propose the low-subrate sparse reconstruction with threshold-adaptive denoising and basis learning(TDBL) algorithm under various low-subrate cases. By analyzing the UAV infrared imagery, it is concluded that infrared aerial images are usually characterized by large number of pixels on some gray levels with double or triple peaks on the histogram, and contain more low-frequency components on the Fourier magnitude spectrum. By jointly considering both recovery quality and runtime, we solve the above l0 minimization problem of BCS reconstruction by the SBI method, instead of IST. To obtain gains during different reconstruction phases, we design an adaptive threshold ρ which is related to model-based methods, such as K-singular value decomposition(SVD) sparse coding[13] and orthogonal matching pursuit(OMP) noise constraint[14]. According to the characteristics of UAV infrared images, an updating expression of ρ is designed by combining image variance and mean value. 展开更多
关键词 model based compressive sensing split bregman iteration transmitter hardware infrared aerial imagery basis learning infrared aerial images threshold adaptive denoising low subrate sparse reconstruction
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Parametic Model for Optimization of Battery Capacity and Power Transmitters of On-line Electric Vehicles in Closed/Open Environments 认领 引用
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作者 Fatima Nisar Syed Haider +3 位作者 Imtiaz Alam Asad Waqar Toqeer Ahmed Mudassar Usman 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2023年第1期185-196,共12页
An on-line electric vehicle(OLEV)uses a wireless charging phenomenon,in which power transmitters are installed beneath the road and the OLEV’s battery is charged remotely.This paper deals with the optimization of two... An on-line electric vehicle(OLEV)uses a wireless charging phenomenon,in which power transmitters are installed beneath the road and the OLEV’s battery is charged remotely.This paper deals with the optimization of two key economic and design parameters,i.e.,the size of the battery and the power transmitters allocation.A complete model configuration of the OLEV system,including the vehicle design and power transmitter,is implemented using MATLAB/Simulink.The battery’s state of charge(SOC)rises and drops according to the vehicle’s velocity and power collection and consumption.The mixed integer programming(MIP)model is used for cost calculation.Therefore,with the help of the SOC graph and MIP model,the battery size and the number of power transmitters,along with their placements,are optimized.The proposed model is applicable to both closed and open environments as it accepts both regulated and deregulated velocities.Two test cases are performed for this purpose.The first test case deals with regulated velocity for which we have applied the KAIST campus OLEV’s velocity along with its 13 kWh battery size and 4 power transmitters,and then applied the suggested solution with the same velocity and route i.e.,8 power transmitters with shorter lengths and reduced battery size(3.25 kWh;one-fourth of the first case).SOC is found within limits at the end of the route,saving$1600 and validating the proposed model in this paper.For the second test case,we use deregulated velocity and optimize both parameters,using the same approach. 展开更多
关键词 Closed and open environments mixed integer programming on-line electrical vehicle power transmitters state of charge wireless charging
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