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Recent progress on high-precision construction of nanoarchitectured SERS substrates for ultrasensitive bio-medical sensors
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作者 Heguang Liu Ben Mou +8 位作者 Jinxin Li Na Tian Yiming Feng Xiaodong Cui Yury Kapitonov Huageng Liang Caiyin You Yuan Li Tianyou Zhai 《Advanced Powder Materials》 2025年第4期30-57,共28页
Surface-enhanced Raman spectroscopy(SERS)has evolved from a laboratory technique to a practical tool for ultra-sensitive detection,particularly in the biomedical field,where precise molecular identification is crucial... Surface-enhanced Raman spectroscopy(SERS)has evolved from a laboratory technique to a practical tool for ultra-sensitive detection,particularly in the biomedical field,where precise molecular identification is crucial.Despite significant advancements,a gap remains in the literature,as no comprehensive review systematically addresses the high-precision construction of SERS substrates for ultrasensitive biomedical detection.This review fills that gap by exploring recent progress in fabricating high-precision SERS substrates,emphasizing their role in enabling ultrasensitive bio-medical sensors.We carefully examine the key to these advancements is the precision engineering of substrates,including noble metals,semiconductors,carbon-based materials,and two-dimensional materials,which is essential for achieving the high sensitivity required for ultrasensitive detection.Applications in biomedical diagnostics and molecular analysis are highlighted.Finally,we address the challenges in SERS substrate preparation and outline future directions,focusing on improvement strategies,design concepts,and expanding applications for these advanced materials. 展开更多
关键词 SERS SERS substrates high-precision construction Ultrasensitive bio-medical sensors Enhancement mechanism
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High-precision large-aperture single-frame interferometric surface profile measurement method based on deep learning
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作者 Liang Tang Mingzhi Han +3 位作者 Shuai Yang Ye Sun Lirong Qiu Weiqian Zhao 《International Journal of Extreme Manufacturing》 2025年第5期481-492,共12页
Large-aperture optical components are of paramount importance in domains such as integrated circuits,photolithography,aerospace,and inertial confinement fusion.However,measuring their surface profiles relies predomina... Large-aperture optical components are of paramount importance in domains such as integrated circuits,photolithography,aerospace,and inertial confinement fusion.However,measuring their surface profiles relies predominantly on the phase-shifting approach,which involves collecting multiple interferograms and imposes stringent demands on environmental stability.These issues significantly hinder its ability to achieve real-time and dynamic high-precision measurements.Therefore,this study proposes a high-precision large-aperture single-frame interferometric surface profile measurement(LA-SFISPM)method based on deep learning and explores its capability to realize dynamic measurements with high accuracy.The interferogram is matched to the phase by training the data measured using the small aperture.The consistency of the surface features of the small and large apertures is enhanced via contrast learning and feature-distribution alignment.Hence,high-precision phase reconstruction of large-aperture optical components can be achieved without using a phase shifter.The experimental results show that for the tested mirror withΦ=820 mm,the surface profile obtained from LA-SFISPM is subtracted point-by-point from the ground truth,resulting in a maximum single-point error of 4.56 nm.Meanwhile,the peak-to-valley(PV)value is 0.0758λ,and the simple repeatability of root mean square(SR-RMS)value is 0.00025λ,which aligns well with the measured results obtained by ZYGO.In particular,a significant reduction in the measurement time(reduced by a factor of 48)is achieved compared with that of the traditional phase-shifting method.Our proposed method provides an efficient,rapid,and accurate method for obtaining the surface profiles of optical components with different diameters without employing a phase-shifting approach,which is highly desired in large-aperture interferometric measurement systems. 展开更多
关键词 large-aperture optical components single-frame interferometric surface profile deep learning dynamic high-precision measurement
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An efficient and high-precision algorithm for solving multiple deformation modes of elastic beams
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作者 Yunzhou WANG Binbin ZHENG +2 位作者 Lingling HU Nan SUN Minghui FU 《Applied Mathematics and Mechanics(English Edition)》 2025年第9期1753-1770,共18页
The elliptic integral method(EIM) is an efficient analytical approach for analyzing large deformations of elastic beams. However, it faces the following challenges.First, the existing EIM can only handle cases with kn... The elliptic integral method(EIM) is an efficient analytical approach for analyzing large deformations of elastic beams. However, it faces the following challenges.First, the existing EIM can only handle cases with known deformation modes. Second,the existing EIM is only applicable to Euler beams, and there is no EIM available for higher-precision Timoshenko and Reissner beams in cases where both force and moment are applied at the end. This paper proposes a general EIM for Reissner beams under arbitrary boundary conditions. On this basis, an analytical equation for determining the sign of the elliptic integral is provided. Based on the equation, we discover a class of elliptic integral piecewise points that are distinct from inflection points. More importantly, we propose an algorithm that automatically calculates the number of inflection points and other piecewise points during the nonlinear solution process, which is crucial for beams with unknown or changing deformation modes. 展开更多
关键词 elastic beam elliptic integral deformation mode transition equilibrium path high-precision algorithm
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Research on Integrated Circuit Talent Stability Construction Based on Turnover Attribution in High-Precision, Specialized, and Innovative Enterprises
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作者 Mingjie Cheng Ziying Chen +1 位作者 Xiayuan Huang Zhixin Jian 《Proceedings of Business and Economic Studies》 2025年第5期87-94,共8页
With the intensifying competition in the integrated circuit(IC)industry,the high turnover rate of integrated circuit engineers has become a prominent issue affecting the technological continuity of high-precision,spec... With the intensifying competition in the integrated circuit(IC)industry,the high turnover rate of integrated circuit engineers has become a prominent issue affecting the technological continuity of high-precision,specialized,and innovative enterprises.As a representative of such enterprises,JL Technology has faced challenges to its R&D efficiency due to talent loss in recent years.This study takes this enterprise as a case to explore feasible paths to reduce turnover rates through optimizing training and career development systems.The research designs a method combining learning maps and talent maps,utilizes a competency model to clarify the direction for engineers’skill improvement,implements talent classification management using a nine-grid model,and achieves personalized training through Individual Development Plans(IDPs).Analysis of the enterprise’s historical data reveals that the main reasons for turnover are unclear career development paths and insufficient resources for skill improvement.After pilot implementation,the turnover rate in core departments decreased by 12%,and employee satisfaction with training increased by 24%.The results indicate that matching systematic talent reviews with dynamic learning resources can effectively enhance engineers’sense of belonging.This study provides a set of highly operational management tools for small and medium-sized high-precision,specialized,and innovative technology enterprises,verifies their applicability in such enterprises,and offers replicable experiences for similar enterprises to optimize their talent strategies[1]. 展开更多
关键词 high-precision specialized and innovative enterprises IC engineers Learning map Talent review Talent map
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Facile synthesis,multimode and tunable luminescence,and multifunctional applications of rare earth ions-activated lead-free double perovskite crystals
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作者 Huilin Li Guang Jia +3 位作者 Zhaoxin Meng Qile Guo Yunyu Bai Cuimiao Zhang 《Journal of Rare Earths》 2025年第10期2108-2116,I0002,共10页
Lead-free double perovskites have gained recognition as top luminescent materials due to their environmental friendliness,high chemical stability,structural adjustability,and excellent photoelectric properties.However... Lead-free double perovskites have gained recognition as top luminescent materials due to their environmental friendliness,high chemical stability,structural adjustability,and excellent photoelectric properties.However,the poor modulation of emission restricts their applications,and it is highly desirable to explore stable and efficient double perovskites with multimode luminescence and adjustable spectra for multifunctional photoelectric applications.Herein,the rare earth ions Ln^(3+)(Er^(3+)and Ho^(3+))-doped Cs_(2)NaYCl_(6):Sb^(3+)crystals were synthesized by a simple solvothermal route.The X-ray diffraction pattern(XRD),energy-dispersive spectroscopy(EDS),X-ray photoelectron spectroscopy(XPS),and elemental mapping images demonstrate that the Sb^(3+),Er^(3+),and Ho^(3+)ions have been homogeneously incorporated into the Cs_(2)NaYCl_(6)crystals.As anticipated,the emissio n spectra of Cs_(2)NaYCl_(6):Sb^(3+)/Ln^(3+)are composed of two bands.One broad blue band derives from self-trapped exciton(STE)in[SbCl_(6)]3-octahedra while another group of emission peaks stems from the f-f transitions of Ln^(3+)ions.The emission colors of Cs_(2)NaYCl_(6):Sb^(3+)/Ln^(3+)phosphors can be tuned in a wide range by modulating the doping concentrations of Ln^(3+)ions.The efficient energy transfer from STE to Ln^(3+)is the key point to achieving the efficient and tunable emissions Cs_(2)NaYCl_(6):Sb^(3+)/Ln^(3+)samples.Interestingly,Cs_(2)NaYCl_(6):Sb^(3+)/Ln^(3+)can also exhibit characteristic up-conversion luminescence of Ln^(3+)under nearinfrared(NIR)excitation besides the down-conversion luminescence,revealing that the materials may have potential applicability in multimode anti-counterfeiting and information encryption applications.Furthermore,the light emitting diodes(LEDs)assembled by Cs_(2)NaYCl_(6):Sb^(3+)and Cs_(2)NaYCl_(6):Sb^(3+)/Ln^(3+)phosphors display dazzling blue,green,and red emissions under a forward bias current,which indicates that the as-obtained double perovskites materials may have great potential in solid-state lighting and optoelectronic devices. 展开更多
关键词 Lead-free double perovskites Rare earthions doping Tunable luminescence multimode anti-counterfeiting LED devices
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Tailoring temperature response for a multimode fiber
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作者 Han Gao Haifeng Hu Qiwen Zhan 《Opto-Electronic Science》 2025年第1期12-24,共13页
This work introduces special states for light in multimode fibers featuring strongly enhanced or reduced correlations be-tween output fields in the presence of environmental temperature fluctuations.Using experimental... This work introduces special states for light in multimode fibers featuring strongly enhanced or reduced correlations be-tween output fields in the presence of environmental temperature fluctuations.Using experimentally measured multi-tem-perature transmission matrix,a set of temperature principal modes that exhibit resilience to disturbances caused by tem-perature fluctuations can be generated.Reversing this concept also allows the construction of temperature anti-principal modes,with output profiles more susceptible to temperature influences than the unmodulated wavefront.Despite changes in the length of the multimode fiber within the temperature-fluctuating region,the proposed approach remains capable of robustly controlling the temperature response within the fiber.To illustrate the practicality of the proposed spe-cial state,a learning-empowered fiber specklegram temperature sensor based on temperature anti-principal mode sensi-tization is proposed.This sensor exhibits outstanding superiority over traditional approaches in terms of resolution and accuracy.These novel states are anticipated to have wide-ranging applications in fiber communication,sensing,imaging,and spectroscopy,and serve as a source of inspiration for the discovery of other novel states. 展开更多
关键词 multimode fiber principal mode wavefront shaping optical fiber sensor temperature response
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Fusing Geometric and Temporal Deep Features for High-Precision Arabic Sign Language Recognition
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作者 Yazeed Alkharijah Shehzad Khalid +2 位作者 Syed Muhammad Usman Amina Jameel Danish Hamid 《Computer Modeling in Engineering & Sciences》 2025年第7期1113-1141,共29页
Arabic Sign Language(ArSL)recognition plays a vital role in enhancing the communication for the Deaf and Hard of Hearing(DHH)community.Researchers have proposed multiple methods for automated recognition of ArSL;howev... Arabic Sign Language(ArSL)recognition plays a vital role in enhancing the communication for the Deaf and Hard of Hearing(DHH)community.Researchers have proposed multiple methods for automated recognition of ArSL;however,these methods face multiple challenges that include high gesture variability,occlusions,limited signer diversity,and the scarcity of large annotated datasets.Existing methods,often relying solely on either skeletal data or video-based features,struggle with generalization and robustness,especially in dynamic and real-world conditions.This paper proposes a novel multimodal ensemble classification framework that integrates geometric features derived from 3D skeletal joint distances and angles with temporal features extracted from RGB videos using the Inflated 3D ConvNet(I3D).By fusing these complementary modalities at the feature level and applying a majority-voting ensemble of XGBoost,Random Forest,and Support Vector Machine classifiers,the framework robustly captures both spatial configurations and motion dynamics of sign gestures.Feature selection using the Pearson Correlation Coefficient further enhances efficiency by reducing redundancy.Extensive experiments on the ArabSign dataset,which includes RGB videos and corresponding skeletal data,demonstrate that the proposed approach significantly outperforms state-of-the-art methods,achieving an average F1-score of 97%using a majority-voting ensemble of XGBoost,Random Forest,and SVM classifiers,and improving recognition accuracy by more than 7%over previous best methods.This work not only advances the technical stateof-the-art in ArSL recognition but also provides a scalable,real-time solution for practical deployment in educational,social,and assistive communication technologies.Even though this study is about Arabic Sign Language,the framework proposed here can be extended to different sign languages,creating possibilities for potentially worldwide applicability in sign language recognition tasks. 展开更多
关键词 Arabic sign language recognition multimodal feature fusion ensemble classification skeletal data inflated 3D ConvNet(I3D)
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Ultra-compact wavelength multiplexer/demultiplexer based on subwavelength grating-assisted multimode interference coupler by inverse design
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作者 WEN Jin PAN Yu +1 位作者 WU Zhengwei ZHANG Ying 《Optoelectronics Letters》 2025年第9期513-519,共7页
We proposed and demonstrated the ultra-compact 1310/1550 nm wavelength multiplexer/demultiplexer assisted by subwavelength grating(SWG)using particle swarm optimization(PSO)algorithm in silicon-on-insulator(SOI)platfo... We proposed and demonstrated the ultra-compact 1310/1550 nm wavelength multiplexer/demultiplexer assisted by subwavelength grating(SWG)using particle swarm optimization(PSO)algorithm in silicon-on-insulator(SOI)platform.Through the self-imaging effect of multimode interference(MMI)coupler,the demultiplexing function for 1310 nm and 1550 nm wavelengths is implemented.After that,three parallel SWG-based slots are inserted into the MMI section so that the effective refractive index of the modes can be engineered and thus the beat length can be adjusted.Importantly,these three SWG slots significantly reduce the length of the device,which is much shorter than the length of traditional MMI-based wavelength demultiplexers.Ultimately,by using the PSO algorithm,the equivalent refractive index and width of the SWG in a certain range are optimized to achieve the best performance of the wavelength demultiplexer.It has been verified that the device footprint is only 2×30.68μm^(2),and 1 dB bandwidths of larger than 120 nm are acquired at 1310 nm and 1550 nm wavelengths.Meanwhile,the transmitted spectrum shows that the insertion loss(IL)values are below 0.47 dB at both wavelengths when the extinction ratio(ER)values are above 12.65 dB.This inverse design approach has been proved to be efficient in increasing bandwidth and reducing device length. 展开更多
关键词 subwavelength grating swg using effective refractive index mmi section subwavelength grating multimode interference coupler inverse design particle swarm optimization pso algorithm demultiplexing function
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Multimodal clinical parameters-based immune status associated with the prognosis in patients with hepatocellular carcinoma
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作者 Yu-Zhou Zhang Yuan-Ze Tang +4 位作者 Yun-Xuan He Shu-Tong Pan Hao-Cheng Dai Yu Liu Hai-Feng Zhou 《World Journal of Gastrointestinal Oncology》 2026年第1期75-91,共17页
Hepatocellular carcinoma presents with three distinct immune phenotypes,including immune-desert,immune-excluded,and immune-inflamed,indicating various treatment responses and prognostic outcomes.The clinical applicati... Hepatocellular carcinoma presents with three distinct immune phenotypes,including immune-desert,immune-excluded,and immune-inflamed,indicating various treatment responses and prognostic outcomes.The clinical application of multi-omics parameters is still restricted by the expensive and less accessible assays,although they accurately reflect immune status.A comprehensive evaluation framework based on“easy-to-obtain”multi-model clinical parameters is urgently required,incorporating clinical features to establish baseline patient profiles and disease staging;routine blood tests assessing systemic metabolic and functional status;immune cell subsets quantifying subcluster dynamics;imaging features delineating tumor morphology,spatial configuration,and perilesional anatomical relationships;immunohistochemical markers positioning qualitative and quantitative detection of tumor antigens from the cellular and molecular level.This integrated phenomic approach aims to improve prognostic stratification and clinical decision-making in hepatocellular carcinoma management conveniently and practically. 展开更多
关键词 Hepatocellular carcinoma Immune status PHENOTYPE multimodal parameters PROGNOSIS
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Multimodal artificial intelligence integrates imaging,endoscopic,and omics data for intelligent decision-making in individualized gastrointestinal tumor treatment
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作者 Hui Nian Yi-Bin Wu +5 位作者 Yu Bai Zhi-Long Zhang Xiao-Huang Tu Qi-Zhi Liu De-Hua Zhou Qian-Cheng Du 《Artificial Intelligence in Gastroenterology》 2026年第1期1-19,共19页
Gastrointestinal tumors require personalized treatment strategies due to their heterogeneity and complexity.Multimodal artificial intelligence(AI)addresses this challenge by integrating diverse data sources-including ... Gastrointestinal tumors require personalized treatment strategies due to their heterogeneity and complexity.Multimodal artificial intelligence(AI)addresses this challenge by integrating diverse data sources-including computed tomography(CT),magnetic resonance imaging(MRI),endoscopic imaging,and genomic profiles-to enable intelligent decision-making for individualized therapy.This approach leverages AI algorithms to fuse imaging,endoscopic,and omics data,facilitating comprehensive characterization of tumor biology,prediction of treatment response,and optimization of therapeutic strategies.By combining CT and MRI for structural assessment,endoscopic data for real-time visual inspection,and genomic information for molecular profiling,multimodal AI enhances the accuracy of patient stratification and treatment personalization.The clinical implementation of this technology demonstrates potential for improving patient outcomes,advancing precision oncology,and supporting individualized care in gastrointestinal cancers.Ultimately,multimodal AI serves as a transformative tool in oncology,bridging data integration with clinical application to effectively tailor therapies. 展开更多
关键词 multimodal artificial intelligence Gastrointestinal tumors Individualized therapy Intelligent diagnosis Treatment optimization Prognostic prediction Data fusion Deep learning Precision medicine
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AI-driven integration of multi-omics and multimodal data for precision medicine
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作者 Heng-Rui Liu 《Medical Data Mining》 2026年第1期1-2,共2页
High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging ... High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging foundation models and multimodal learning frameworks are enabling scalable and transferable representations of cellular states,while advances in interpretability and real-world data integration are bridging the gap between discovery and clinical application.This paper outlines a concise roadmap for AI-driven,transcriptome-centered multi-omics integration in precision medicine(Figure 1). 展开更多
关键词 high throughput transcriptomics multi omics single cell multimodal learning frameworks foundation models omics data modalitiesemerging ai driven precision medicine
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High-precision automatic measurement of two-dimensional geometric features based on machine vision 被引量:6
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作者 何博侠 何勇 +1 位作者 薛蓉 杨洪锋 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期428-433,共6页
To realize high-precision automatic measurement of two-dimensional geometric features on parts, a cooperative measurement system based on machine vision is constructed. Its hardware structure, functional composition a... To realize high-precision automatic measurement of two-dimensional geometric features on parts, a cooperative measurement system based on machine vision is constructed. Its hardware structure, functional composition and working principle are introduced. The mapping relationship between the feature image coordinates and the measuring space coordinates is established. The method of measuring path planning of small field of view (FOV) images is proposed. With the cooperation of the panoramic image of the object to be measured, the small FOV images with high object plane resolution are acquired automatically. Then, the auxiliary measuring characteristics are constructed and the parameters of the features to be measured are automatically extracted. Experimental results show that the absolute value of relative error is less than 0. 03% when applying the cooperative measurement system to gauge the hole distance of 100 mm nominal size. When the object plane resolving power of the small FOV images is 16 times that of the large FOV image, the measurement accuracy of small FOV images is improved by 14 times compared with the large FOV image. It is suitable for high-precision automatic measurement of two-dimensional complex geometric features distributed on large scale parts. 展开更多
关键词 machine vision two-dimensional geometric features high-precision measurement automatic measurement
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Tapered Multimode Interference Combiners for Coherent Receivers 被引量:1
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作者 武志刚 张伟刚 +5 位作者 王志 开桂云 袁树中 董孝义 宇高胜之 和田恭雄 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期328-335,共8页
A new tapered multimode interference (MMl)-based coherent lightwave combiner is reported. A comprehensive theoretical analysis of mode behaviors in the tapered MMI waveguide is presented, and the output characterist... A new tapered multimode interference (MMl)-based coherent lightwave combiner is reported. A comprehensive theoretical analysis of mode behaviors in the tapered MMI waveguide is presented, and the output characteristics of the tapered MMI combiners with various structures are demonstrated. The combiner is fabricated on a silicon-on-insulator (SO1) substrate. Due to its advantages of having no end-facet reflection,easy extension to a multi-port configuration, high tolerance for fabrication errors, and compact size, the tapered MMI is a good candidate for a coherent lightwave combiner to be used in large-scale photonic integrated circuits. 展开更多
关键词 integrated optics multimode interference COMBINER SILICON-ON-INSULATOR
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An Efficient MMI SOI Splitter with Multimode Input/Output Waveguides
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作者 方青 贺月娇 +2 位作者 辛红丽 李芳 刘育梁 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第2期276-280,共5页
A 1×8 multimode interference power splitter with multimode input/output waveguides in SOI material is designed by the beam propagation method and fabricated by the inductive coupled plasma etching technology for... A 1×8 multimode interference power splitter with multimode input/output waveguides in SOI material is designed by the beam propagation method and fabricated by the inductive coupled plasma etching technology for use in fiber optics communication systems.The fabricated device exhibits low loss and good coupling uniformity.The excess loss is lower than 0 8dB,and the uniformity is 0 45dB at the wavelength of 1550nm.Moreover,the polarization dependent loss is lower than 0 7dB at 1550nm.The device size is only 2mm×10mm. 展开更多
关键词 multimode interference power splitter SOI multimode input/output waveguides
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Coordinate unification method of high-precision composite measurement in two dimensions 被引量:2
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作者 文信 付鲁华 +2 位作者 赵炎 张恒 王仲 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期205-213,共9页
Multi-sensor coordinate unification in dimensional metrology is used in order to get holistic, more accurate and reliable information about a workpiece based on several or multiple measurement values from ... Multi-sensor coordinate unification in dimensional metrology is used in order to get holistic, more accurate and reliable information about a workpiece based on several or multiple measurement values from one or more sensors. Because of the problem that standard ball is deficient as a standard artifact in the coordinate unification of high-precision composite measurement in two dimensions (2D) , a new method is proposed in this paper which uses angle gauge blocks as standard artifacts to achieve coordinate unification between the image sensor and the tactile probe. By comparing the standard ball with the angle gauge block as a standard artifact, theoretical analysis and experimental results are given to prove that it is more precise and more convenient to use angle gauge blocks as standard artifacts to achieve coordinate unification of high-precision composite measurement in two dimensions. 展开更多
关键词 high-precision composite measurement image sensor tactile probe coordinate unification angle gauge block
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Multimode Process Fault Detection Using Local Neighborhood Similarity Analysis 被引量:6
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作者 邓晓刚 田学民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1260-1267,共8页
Traditional data driven fault detection methods assume unimodal distribution of process data so that they often perform not well in chemical process with multiple operating modes. In order to monitor the multimode che... Traditional data driven fault detection methods assume unimodal distribution of process data so that they often perform not well in chemical process with multiple operating modes. In order to monitor the multimode chemical process effectively, this paper presents a novel fault detection method based on local neighborhood similarity analysis(LNSA). In the proposed method, prior process knowledge is not required and only the multimode normal operation data are used to construct a reference dataset. For online monitoring of process state, LNSA applies moving window technique to obtain a current snapshot data window. Then neighborhood searching technique is used to acquire the corresponding local neighborhood data window from the reference dataset. Similarity analysis between snapshot and neighborhood data windows is performed, which includes the calculation of principal component analysis(PCA) similarity factor and distance similarity factor. The PCA similarity factor is to capture the change of data direction while the distance similarity factor is used for monitoring the shift of data center position. Based on these similarity factors, two monitoring statistics are built for multimode process fault detection. Finally a simulated continuous stirred tank system is used to demonstrate the effectiveness of the proposed method. The simulation results show that LNSA can detect multimode process changes effectively and performs better than traditional fault detection methods. 展开更多
关键词 multimode chemical PROCESS Fault detection LOCAL NEIGHBORHOOD SIMILARITY ANALYSIS Principal component ANALYSIS
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Multimode oscillation Q-switched erbium-doped fiber laser with a few-mode fiber cavity 被引量:3
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作者 HAN Si-meng YANG Kang +2 位作者 WANG Zhen-hong LIU Yan-ge WANG Zhi 《Optoelectronics Letters》 EI 2018年第6期417-420,共4页
We propose and demonstrate experimentally a multimode oscillation Q-switched erbium-doped fiber laser with a few-mode fiber cavity. The different coupling processes of reflection peaks of fiber Bragg gratings(FBGs) wh... We propose and demonstrate experimentally a multimode oscillation Q-switched erbium-doped fiber laser with a few-mode fiber cavity. The different coupling processes of reflection peaks of fiber Bragg gratings(FBGs) which act as cavity mirrors allow the different oscillating states. We obtain microsecond light pulse output states whose oscillation and output beams have different mode compositions, including high order mode. Such a structure enables the high order mode oscillation in the whole cavity with an all-fiber structure, which has potential applications in mode-division multiplexed systems and research of multimode nonlinear effect. 展开更多
关键词 multimode OSCILLATION Q-SWITCHED few-mode fibercavity
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Multimode Design and Analysis of an Integrated Leg-Arm Quadruped Robot with Deployable Characteristics 被引量:3
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作者 Fuqun Zhao Yifan Wu +4 位作者 Xinhua Yang Xilun Ding Kun Xu Sheng Guo Xiaodong Jin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期41-61,共21页
To improve locomotion and operation integration, this paper presents an integrated leg-arm quadruped robot(ILQR) that has a reconfigurable joint. First, the reconfigurable joint is designed and assembled at the end of... To improve locomotion and operation integration, this paper presents an integrated leg-arm quadruped robot(ILQR) that has a reconfigurable joint. First, the reconfigurable joint is designed and assembled at the end of the legarm chain. When the robot performs a task, reconfigurable configuration and mode switching can be achieved using this joint. In contrast from traditional quadruped robots, this robot can stack in a designated area to optimize the occupied volume in a nonworking state. Kinematics modeling and dynamics modeling are established to evaluate the mechanical properties for multiple modes. All working modes of the robot are classified, which can be defined as deployable mode, locomotion mode and operation mode. Based on the stability margin and mechanical modeling, switching analysis and evaluation between each mode is carried out. Finally, the prototype experimental results verify the function realization and switching stability of multimode and provide a design method to integrate and perform multimode for quadruped robots with deployable characteristics. 展开更多
关键词 Quadruped robot multimode design Mode switching Locomotion Operation
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Semi-vectorial analysis of a compact wavelength demultiplexer based on the tapered multimode interference coupler 被引量:1
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作者 肖金标 刘旭 +1 位作者 蔡纯 孙小菡 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期2015-2022,共8页
Based on a parabolically tapered multimode interference (MMI) coupler with a deep-etched SiO2/SiON rib waveguide, a compact wavelength demultiplexer operating at 1.30 and 1.55 μm wavelengths is proposed and analyse... Based on a parabolically tapered multimode interference (MMI) coupler with a deep-etched SiO2/SiON rib waveguide, a compact wavelength demultiplexer operating at 1.30 and 1.55 μm wavelengths is proposed and analysed by using three-dimensional semi-vectorial finite-difference beam propagation method (3D-SV-FD-BPM). The results show that a MMI section of 330.0 μm in length, which is only 76% length of a straight MMI coupler, is achieved with the contrasts of 42.3 and 39.2dB in quasi-TE mode, and 38.4 and 37.8dB in quasi-TM mode at wavelengths 1.30 and 1.55μm, respectively, and the insertion losses below 0.2dB at both wavelengths and in both polarization states, The alternating direction implicit algorithm with the Crank-Nicholson scheme is applied to the discretization of the 3D-SV-FD-BPM formulation along the longitudinal direction. Moreover, a modified FD scheme is constructed to approximate the resulting equations along the transverse directions, in which the discontinuities of the derivatives of magnetic field components Hy and Hx along the vertical and horizontal interfaces, respectively, are involved. 展开更多
关键词 wavelength demultiplexer multimode interference beam propagation method photonic integrated circuits
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Moho depth inversion in the Tibetan Plateau from high-precision gravity data 被引量:4
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作者 HuiYou He Jian Fang +3 位作者 HePing Sun DongMei Guo ZhiXin Xue Jing Hou 《Earth and Planetary Physics》 CAS CSCD 2023年第4期487-498,共12页
The Tibetan Plateau(TP)is the youngest orogenic belt resulting from a continental collision on the Earth.It is a natural laboratory for studying continental dynamics,such as continental convergence,plate subduction,an... The Tibetan Plateau(TP)is the youngest orogenic belt resulting from a continental collision on the Earth.It is a natural laboratory for studying continental dynamics,such as continental convergence,plate subduction,and plateau uplift.Investigating the deep structure of the TP has always been a popular issue in geological research.The Moho is the boundary between the crust and the mantle and therefore plays a crucial role in the Earth’s structure.Parameters such as depth and lateral variation,as well as the fine structure of the crust-mantle interface,reveal the lithospheric dynamics in the TP.Two methods are generally employed to study the Moho surface:seismic detection and gravity inversion.Seismic detection has the characteristic of high precision,but it is limited to a few cross-sectional lines and is quite costly.It is not suitable for and cannot be carried out over a large area of the TP.The Moho depth over a large area can be obtained through gravity inversion,but this method is affected by the nature of gravity data,and the accuracy of the inversion method is lower than that of seismic detection.In this work,a high-precision gravity field model was selected.The Parker-Oldenburg interface inversion method was used,within the constraints of seismic observations,and the Bott iteration method was introduced to enhance the inversion efficiency.The Moho depth in the TP was obtained with high precision,consistent with the seismic detection results.The research results showed that the shape of the Moho in the TP is complex and the variation range is large,reaching 60−80 km.In contrast with the adjacent area,a clear zone of sharp variation appears at the edge of the plateau.In the interior of the TP,the buried depth of the Moho is characterized by two depressions and two uplifts.To the south of the Yarlung Zangbo River,the Moho inclines to the north,and to the north,the Moho depresses downward,which was interpreted as the Indian plate subducting to the north below Xizang.The Moho depression on the north side of the Qiangtang block,reaching 72 km deep,may be a result of the southward subduction of the lithosphere.The Moho uplift of the Qiangtang block has the same strike as the Bangong−Nujiang suture zone,which may indicate that the area is compensated by a low-density and low-velocity mantle. 展开更多
关键词 GRAVITY MOHO Tibetan Plateau SGG-UGM-2(2159-order high-precision gravity field model)
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