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A convenient look-up-table based method for the compensation of non-linear error in digital fringe projection 认领 引用 被引量：10
1
作者 Chen Xiong Jun Yao +1 位作者 Jubing Chen Hong Miao 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2016年第1期49-53,共5页
Although the structured light system that uses digital fringe projection has been widely implemented in three-dimensional surface profile measurement,the measurement system is susceptible to non-linear error.In this w... Although the structured light system that uses digital fringe projection has been widely implemented in three-dimensional surface profile measurement,the measurement system is susceptible to non-linear error.In this work,we propose a convenient look-up-table-based(LUT-based)method to compensate for the non-linear error in captured fringe patterns.Without extra calibration,this LUT-based method completely utilizes the captured fringe pattern by recording the full-field differences.Then,a phase compensation map is established to revise the measured phase.Experimental results demonstrate that this method works effectively. 展开更多
关键词 Phase measurement Digital fringe projection Non-linear error compensation Digital image processing
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A SCR method for uncertainty estimation in geodesy non-linear error propagation: Comparisons and applications 认领 引用 被引量：1
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作者 Chuanyi Zou Hao Ding Leyang Wang 《Geodesy and Geodynamics》 EI CSCD 2022年第4期311-320,共10页
We review three derivative-free methods developed for uncertainty estimation of non-linear error propagation, namely, MC(Monte Carlo), SUT(scaled unscented transformation), and SI(sterling interpolation). In order to ... We review three derivative-free methods developed for uncertainty estimation of non-linear error propagation, namely, MC(Monte Carlo), SUT(scaled unscented transformation), and SI(sterling interpolation). In order to avoid preset parameters like as these three methods need, we introduce a new method to uncertainty estimation for the first time, namely, SCR(spherical cubature rule), which is no need for setting parameters. By theoretical derivation, we prove that the precision of uncertainty obtained by SCR can reach second-order. We conduct four synthetic experiments, for the first two experiments, the results obtained by SCR are consistent with the other three methods with optimal setting parameters, but SCR is easier to operate than other three methods, which verifies the superiority of SCR in calculating the uncertainty. For the third experiment, real-time calculation is required, so the MC is hardly feasible. For the forth experiment, the SCR is applied to the inversion of seismic fault parameter which is a common problem in geophysics, and we study the sensitivity of surface displacements to fault parameters with errors. Our results show that the uncertainty of the surface displacements is the magnitude of ±10 mm when the fault length contains a variance of 0.01 km2. 展开更多
关键词 SCR method Uncertainty estimation Non-linear error propagation Inversion of seismic fault parameter
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A Method on Non-Linear Correction of Broadband LFMCW Signal Utilizing Its Relative Sweep Non-Linear Error 认领 引用
3
作者 Chen Zhuming Ding Yiyuan & Xiang Jingcheng Dept. of Electronic Engineering, UEST, Chengdu 610054, P. R. China 《Journal of Systems Engineering and Electronics》 EI 2001年第1期70-74,共5页
This paper presents a method on non-linear correction of broadband LFMCW signal utilizing its relative nonlinear error. The deriving procedure and the results simulated by a computer and tested by a practical system a... This paper presents a method on non-linear correction of broadband LFMCW signal utilizing its relative nonlinear error. The deriving procedure and the results simulated by a computer and tested by a practical system are also introduced. The method has two obvious advantages compared with the previous methods: (1) Correction has no relation with delay time td and sweep bandwidth B; (2) The inherent non-linear error of VCO has no influence on the correction and its last results. 展开更多
关键词 Computer simulation Control nonlinearities Error correction Frequency modulation Signal processing Variable frequency oscillators
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Multi-source errors evaluation of machine tools:from research gaps to methodologies and applications 认领 引用 被引量：1
4
作者 Jingang Sun Yanbin Zhang +14 位作者 Xiao Ma Benkai Li Min Yang Liandi Xu Haiyuan Xin Qinglong An Lida Zhu Qingfeng Bie Xianxin Yin Shouhai Chen Guanqun Li Yusuf Suleiman Dambatta Rui Xue Zhenwei Yu Changhe Li 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2026年第2期44-96,共53页
Multi-source errors,as critical obstacles limiting the accuracy retention and machining performance of machine tools,hold fundamental and strategic significance for achieving high-precision,high-efficiency,and high-re... Multi-source errors,as critical obstacles limiting the accuracy retention and machining performance of machine tools,hold fundamental and strategic significance for achieving high-precision,high-efficiency,and high-reliability machining in modern manufacturing systems.However,these errors typically exhibit complex characteristics such as strong coupling,time-variance,and nonlinearity,which challenge traditional methods of error identification,modeling,and compensation in terms of adaptability,real-time capability,and integration.Therefore,it is imperative to establish a systematic and intelligent multi-source error control framework.Firstly,this work systematically reviews typical error sources and their evolution mechanisms,evaluates multi-scale detection technologies including laser interferometry,double ball-bar systems,multi-sensor fusion,and vision-based systems,and constructs an intelligent error identification and evaluation framework.Next,it reviews classical modeling methods such as homogeneous transformation matrices,screw theory,thermal equilibrium models,finite element analysis,and modal analysis,compares physical modeling,data-driven,and hybrid modeling strategies,and develops an integrated multi-source error modeling architecture centered on digital twin technology and artificial intelligence.Furthermore,key technologies,including geometric error mapping and real-time compensation,online thermal error prediction and active temperature control,dynamic error suppression,and adaptive control,are summarized.A multi-level integrated error compensation architecture is proposed by combining physical models,data models,and cyber-physical synchronization.This architecture encompasses core processes such as error traceability and decoupling,dynamic prediction,real-time compensation,and closed-loop optimization,emphasizing engineering implementation mechanisms based on cyber-physical collaboration,multi-physics coupling,and multi-scale fusion,thereby effectively enhancing accuracy stability and control robustness under complex operating conditions.Finally,frontier challenges such as constructing high-fidelity coupled models from heterogeneous multi-source data,edge-cloud collaborative control,and cross-platform interoperability are discussed.The application prospects of multi-source error evaluation are also envisioned,providing theoretical foundations and technical support for the precise management and optimization of the entire lifecycle accuracy of machine tools. 展开更多
关键词 multi-source error evaluation error coupling integrated error modeling traceability and decoupling hybrid prediction closed-loop error compensation
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A contouring error prediction and compensation method for a blisk machining center 认领 引用
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作者 Dong WANG Ce HAN +7 位作者 Liping WANG Jinfeng LI Xuekun LI Yun ZHANG Hongli YANG Yongjie SUN Yiming CHEN Yunzhi LYU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第6期741-756,共16页
The aero-engine blisk has large size and complex structure,leading to drastic variations in driving axis speed during machining process,which brings a critical challenge for efficient and stable contouring error contr... The aero-engine blisk has large size and complex structure,leading to drastic variations in driving axis speed during machining process,which brings a critical challenge for efficient and stable contouring error control.Pure trajectory planning fails to perfectly smooth the variation of speed due to the complex structure of blisk.Additionally,advanced controllers often reduce the stability of control systems,limiting their application in commercial Computer Numerical Control(CNC)machine tools.To address these problems,this paper proposes an effective and practical contouring error prediction and compensation method for a blisk machining center.First,the tracking error of driving axis is accurately calculated to overcome the time delay in feedback.Subsequently,the contouring error is predicted combining the tracking error of driving axis with the geometrical structure of blisk machining center.In terms of contouring error compensation,speed feedforward compensation is employed to enhance the tracking performance of driving axis,while command modification is applied to further improve contouring accuracy without affecting system stability.Based on the experimental results,the tracking error of driving axis and contouring error achieve high prediction accuracy with the deviations of average values below 6.49%and 12.41%under three different motion conditions,respectively;moreover,the contouring error of the sample trajectory is reduced to the micron level after speed feedforward compensation,and further decreased more than 32.85%through command modification.A typical blisk sample is finally machined successfully,validates the effectiveness and practicability of the proposed method. 展开更多
关键词 Blisk machining center Contouring error Error compensation Error prediction Tracking error of driving axis
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Moving Beyond a Zero Tolerance Mindset:Embracing Action Errors in Construction 认领 引用
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作者 Peter E.D.Love Jane Matthews Weili Fang 《Engineering》 SCIE EI CSCD 2026年第2期159-164,共6页
Action errors-unintentional deviations from goals,rules,or standards-are an inevitable part of work in construction.Understanding how individuals and organizations can embrace and"learn through errors"(i.e.,... Action errors-unintentional deviations from goals,rules,or standards-are an inevitable part of work in construction.Understanding how individuals and organizations can embrace and"learn through errors"(i.e.,how to handle them effectively)is crucial for contributing to project success.However,within construction,a prevailing belief persists that errors can and should be eliminated,fostering a zero-tolerance mindset.Organizations that adopt this mindset risk stifling their capacity to learn,innovate,and improve profitability.While errors can indeed have negative consequences,they also play a vital role in enabling learning and innovation.Given the limited empirical research on action errors in construction,this paper aims to stimulate inquiry into this promising area of study.It briefly outlines different forms of error orientation and proposes directions for future research relevant to construction organizations.The contributions of this paper are twofold,as it:①advocates for construction organizations to broaden their understanding of errors to enhance their learning capability and②identifies ways in which organizations can improve their capacity to learn and innovate through error management. 展开更多
关键词 Action errors Construction Error prevention Error management Learning
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Statistical characteristics mining of measured machining error of multi-stage compressor blisks 认领 引用
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作者 Yue DAN Limin GAO +3 位作者 Yuyang HAO Qiusheng LUO Ruiyu LI Guang YANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第5期173-185,共13页
Blisks have been widely adopted in various aero-engines due to the advantages such as simple structure and low loss.However,influenced by machining errors,the geometric inconsistency of blisk blades is significant,lea... Blisks have been widely adopted in various aero-engines due to the advantages such as simple structure and low loss.However,influenced by machining errors,the geometric inconsistency of blisk blades is significant,leading to deviations in the compressor performance from the design and scatter increase.To accurately assess performance uncertainty effects of machining errors using uncertainty quantification methods,‘statistical characteristics of machining errors’as uncertainty quantification inputs are particularly critical.This study is the first to highlight measured machining errors'uncertainty analysis for blisks.Measured machining errors from the front,middle,and rear stages of multi-stage compressor blisks are analyzed regarding their systematic deviations and scatters along the radial direction,and probability distribution characteristics.The results show that due to differences in clamping and fixing methods,the statistical characteristics of machining errors for‘blisk'differ from those of‘single blade’.Additionally,variations in material properties and sizes of blades at different compressor stages lead to differences in the statistical characteristics of machining errors.For different sections,systematic deviations and scatters in machining errors are notably significant near the blade tip,making it challenging to ensure machining consistency.For different stages,machining errors of the rear stage blades are the most scattering.Compared with the design geometry,several phenomena observed in most blades,such as‘under deflection’,‘thicker pressure/suction surfaces’and‘larger leading-edge radius’,should be improved,owing to their adverse effects in compressors.Furthermore,probability distributions of machining errors exhibit characteristics such as‘skewness’,‘bimodality’,and‘data missing’,indicating that traditional normal distributions are insufficient for accurately characterizing the above distributions.The research results provide a clear demonstration of the machining capabilities of compressor blisks and offer data support for correctly constructing probability models of machining errors,thereby enabling accurate prediction of their performance uncertainty effects. 展开更多
关键词 Blade Compressor Machining error Measured data Statistical analysis
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Retaining local chemical effects:An error cancellation strategy for calculating standard gas-phase enthalpy of formation 认领 引用
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作者 Rui Liu Chaoyang Zhang +2 位作者 Linyuan Wang Zhiyu Huang Jian Liu 《Defence Technology（防务技术）》 SCIE EI CAS CSCD 2026年第1期172-179,共8页
Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches m... Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches may be ineffective for systems with strong localized chemical effects,as fragmenting specific substructures into simpler chemical bonds can introduce additional errors instead of mitigating them.To address this issue,we propose the Substructure-Preserved Connection-Based Hierarchy(SCBH),a method that automatically identifies and freezes substructures with significant local chemical effects prior to molecular fragmentation.The SCBH is validated by the gas-phase enthalpy of formation calculation of CHNO molecules.Therein,based on the atomization scheme,the reference and test values are derived at the levels of Gaussian-4(G4)and M062X/6-31+G(2df,p),respectively.Compared to commonly used approaches,SCBH reduces the average computational error by half and requires only15%of the computational cost of G4 to achieve comparable accuracy.Since different types of local effect structures have differentiated influences on gas-phase enthalpy of formation,substituents with strong electronic effects should be retained preferentially.SCBH can be readily extended to diverse classes of organic compounds.Its workflow and source code allow flexible customization of molecular moieties,including azide,carboxyl,trinitromethyl,phenyl,and others.This strategy facilitates accurate,rapid,and automated computations and corrections,making it well-suited for high-throughput molecular screening and dataset construction for gas-phase enthalpy of formation. 展开更多
关键词 Gas-phase enthalpy of formation Error cancellation Quantum chemical High throughput
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Quantum toric code decoding method based on syndrome-preliminary error fusion module and ResNet architecture 认领 引用
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作者 Nai-Hua Ji Ping-Li Song +2 位作者 Wei Wang Hui-Qian Sun Hong-Yang Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第6期649-659,共11页
Quantum error correction technology is based on the principle of redundant encoding,encoding logical quantum information into multiple physical qubits to provide important support for the stable operation of quantum c... Quantum error correction technology is based on the principle of redundant encoding,encoding logical quantum information into multiple physical qubits to provide important support for the stable operation of quantum computers.To address the issues of low decoding accuracy and limited feature extraction in quantum error correction,this paper proposes a toric code decoder based on a syndrome-preliminary error fusion module(SPEFM)and a ResNet architecture.This decoder takes full advantage of the correlations between X and Z errors.In the SPEFM,the syndrome and preliminary error predictions are deeply fused,while a unidirectional Swin transformer architecture is incorporated to extract global error features from the syndrome data,signiffiificantly improving both decoding accuracy and computational efffiificiency.In addition,this paper further extracts local error features from the fused features using the deep residual structure of ResNet,enhancing the decoder's ability to capture quantum error patterns.Experimental results show that the decoder is applicable to different code distances(d=4,6,8,10)under the depolarizing noise model.Its bit error rate is lower than that of the minimum weight perfect matching(MWPM)algorithm,and its logical error rate is lower than both the MWPM algorithm and the ResNet18 decoder.Furthermore,the decoding threshold is increased to 0.163,representing a 3.82%improvement over the MWPM algorithm threshold of 0.157. 展开更多
关键词 quantum error correction toric code ResNet Swin transformer
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High-precision color crosstalk coefficient calibration method based on phase error estimation 认领 引用
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作者 FENG Lu-yuan LIANG Jian +3 位作者 WANG Xiang-jun ZHAO Zong-yang CHEN Yi-fan WU Bin 《中国光学（中英文）》 EI CAS CSCD 北大核心 2026年第3期745-753,共9页
Color-coded fringe patterns have emerged as a key technique for enabling real-time three-dimen-sional(3D)shape measurement in fringe projection profilometry(FPP).However,color crosstalk inherent in color cameras remai... Color-coded fringe patterns have emerged as a key technique for enabling real-time three-dimen-sional(3D)shape measurement in fringe projection profilometry(FPP).However,color crosstalk inherent in color cameras remains a significant factor limiting measurement accuracy.To mitigate this issue,a high-pre-cision calibration method for color crosstalk coefficients is proposed to enable effective correction in this pa-per.Specifically,a crosstalk coefficient estimator is developed based on orthogonal phase-shifted fringe pat-terns,and the theoretical relationship between the crosstalk coefficients and phase error is derived.The color orthogonal fringes are then designed to project onto a standard planar target to acquire separated R,G,and B channel patterns.Finally,a particle swarm optimization(PSO)algorithm is introduced to optimize the crosstalk-induced phase errors and calibrate the crosstalk coefficients with high precision.Experimental val-idation based on a standard dual-sphere calibration plate shows that the diameter fitting errors of the two spheres are 0.0191 mm and 0.0160 mm,respectively,and the error in the calculated center-to-center distance is as low as 0.0120 mm,which demonstrate that the proposed method can effectively enhance the measure-ment accuracy and applicability of color cameras in fringe projection technology. 展开更多
关键词 fringe projection profilometry color crosstalk coefficient phase error orthogonal fringe pattern
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Research on ultraprecision turning and profile-error compensation technology for multi-axis linkage 认领 引用
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作者 Xipeng Guo Jiabin Yuan +1 位作者 Wei Shi Shaohui Yin 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2026年第1期60-69,共10页
In an ultraprecision turning process for small-diameter optical aspheric workpieces,tool-profile errors induce mid-frequency errors in the workpiece profile,limiting further improvements in precision.In this study,an ... In an ultraprecision turning process for small-diameter optical aspheric workpieces,tool-profile errors induce mid-frequency errors in the workpiece profile,limiting further improvements in precision.In this study,an XZB three-axis linkage ultraprecision machining method is proposed,and the effects of tool-center errors are analyzed.To address residual errors in Z-direction profile-error compensation,a workpiece normal-profile-error compensation method is proposed.After XZB three-axis linkage turning and compensation,the workpiece profile error(PV)reaches 0.086μm,surpassing the precision of XZ two-axis machining,and mid-frequency errors are reduced.Compared with Z-direction profile-error compensation,which results in a profile error of 0.092μm,normal-profile-error compensation reduces PV to 0.047μm,considerably improving aspheric accuracy.Experimental results demonstrate that XZB three-axis linkage machining significantly improves the aspheric workpiece profile,enhancing both its accuracy and surface quality.This method reduces mid-frequency errors,and the subsequent application of normal-profile-error compensation further refines the profile,achieving higher overall accuracy. 展开更多
关键词 Aspheric workpiece Ultraprecision turning XZB three-axis linkage Normal error compensation
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X-ray pulsar-based airborne clock error estimation using Gaussian process 认领 引用
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作者 Yusong WANG Yidi WANG +4 位作者 Kun JIANG Wenhai JIAO Minzhang SONG Liansheng LI Wei ZHENG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第4期541-550,共10页
In order to autonomously calibrate the airborne clocks of deep space explorers,this paper proposes an X-ray pulsar-based airborne clock error estimation method.A pulse phase propagation model incorporating the clock e... In order to autonomously calibrate the airborne clocks of deep space explorers,this paper proposes an X-ray pulsar-based airborne clock error estimation method.A pulse phase propagation model incorporating the clock error is derived.Given that both the clock noise and the pulsar timing noise are of power-law spectral densities,their combination is modeled as a Fractional Brownian Motion(FBM)with a fractional-order power spectral density.The clock error series is modeled as a Gaussian Process(GP)with a mean function in the form of 2-order polynomial and an FBM-based covariance function.Finally,the clock error and the hyperparameters of GP are fast estimated by an iterated estimation method.The proposed method is validated via the real clock error data of the G05 satellite in the Global Positioning System(GPS)and the real data of pulsars from the Neutron star Interior Composition ExploreR(NICER). 展开更多
关键词 Atomic clock Clock error estimation Fractional Brownian motion Gaussian process X-ray pulsar
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Modelling and experimental investigation of frequency splitting of hemispherical resonator with machining errors 认领 引用
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作者 Chuanzhen MA Henan LIU +1 位作者 Jian CHENG Mingjun CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第5期609-625,共17页
Hemispherical Resonator(HSR)is a typical high-performance component due to the complex coupling relationship between the machining errors and performance parameters.To understand the impact of machining errors on freq... Hemispherical Resonator(HSR)is a typical high-performance component due to the complex coupling relationship between the machining errors and performance parameters.To understand the impact of machining errors on frequency splitting,the frequency splitting model that couples the multiple machining errors was developed to elucidate the mechanism of frequency splitting and reveal the effect of geometric error parameters on frequency splitting innovatively.In addition,a method for characterizing machining errors is established to describe the circumferential mass uniformity of the hemispherical shell.Furthermore,measurement experiments of HSRs were performed to verify the accuracy of the model,and the results showed that the predicted errors of the model were within 15%.Both theoretical and experimental results demonstrated that the direct cause of frequency splitting is the uneven circumferential mass of HSR.In particular,the radial concentricity has the most significant influence on frequency splitting,followed by the coaxiality and roundness.Within the error range of 0–0.5μm,frequency splitting values change by 0.945 Hz,0.098 Hz,and 0.039 Hz,respectively.Furthermore,the coupling effect of machining errors and surface quality on frequency splitting was discussed,which showed machining errors is the predominant factor contributing to frequency splitting.This work not only enhance the understanding of the mechanism of frequency splitting,but also provide theoretical guidance for the parameter optimization involved in high-performance manufacturing of HSR. 展开更多
关键词 Frequency splitting Hemispherical resonator Machining errors Mass nonuniformity Surface quality
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Digital twin‐based error motion monitoring and prediction method for aerostatic spindle 认领 引用
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作者 Guoda Chen Shenghao Tang +2 位作者 Yuting Jiang Dingxu Zhou Dapeng Tan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第1期57-73,共17页
The aerostatic spindle is a key component of ultra-precision machine tools,and its error motion is crucial to machining accuracy and reliability.Spindle error motion is unavoidable,and its online monitoring and predic... The aerostatic spindle is a key component of ultra-precision machine tools,and its error motion is crucial to machining accuracy and reliability.Spindle error motion is unavoidable,and its online monitoring and prediction are quite important.Currently,there are relatively few studies on the online monitoring and prediction methods for the aerostatic spindle,and the level of intelligence is relatively low.To address this problem,an error motion monitoring system based on digital twin(DT)technology was established for the aerostatic spindle.A spindle error motion prediction method based on a mechanism and data fusion model(MDFM)was proposed.Additionally,a highly available and interactive aerostatic spindle DT service platform was developed.Experimental results have verified the good performance of this platform.The platform facilitates interaction between the physical and virtual entities of the aerostatic spindle,enabling three-dimensional visualization,monitoring,prediction,and simulation of spindle error motion,and shows good potential for engineering applications. 展开更多
关键词 Aerostatic spindle Digital twin Mechanism and data fusion model Spindle error motion monitoring
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Monitoring and correction of errors in state space representation products using PPP float ambiguity deviations and phase residuals in a wide-area network 认领 引用
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作者 Yunqing Tian Bao Shu +6 位作者 Yuhang Zheng Guillermo González‑Casado Yang Gao Li Wang Adria Rovira‑Garcia Guanwen Huang Qin Zhang 《Satellite Navigation》 SCIE EI CSCD 2026年第1期180-199,I0005,共20页
Real‑time Precise Point Positioning with Ambiguity Resolution(PPP‑AR)critically depends on high‑quality State Space Representation(SSR)products for satellite orbit,clock,and code/phase bias corrections.These products,... Real‑time Precise Point Positioning with Ambiguity Resolution(PPP‑AR)critically depends on high‑quality State Space Representation(SSR)products for satellite orbit,clock,and code/phase bias corrections.These products,however,often contain errors that can severely degrade user positioning performance.Existing network‑based quality monitor ing methods primarily rely on phase residuals to detect product errors.However,phase residuals are only effective in revealing SSR product errors after ambiguities have been fixed.Before ambiguities are fixed,the stable or slowly varying components of SSR product errors are absorbed into the float ambiguities,rendering such phase residuals insufficient to fully reveal SSR product errors.As a result,the products with unfixed ambiguities are typically tagged as unreliable due to their uncertain quality.This practice however reduces the availability of SSR products and limit user PPP‑AR performance,particularly in challenging environments where fewer satellites are visible.To address this limitation,this study proposes a method that effectively monitors SSR product quality by jointly considering the devi ations of float ambiguities from their true integer values and phase residuals associated with float ambiguities.Unlike the ambiguity‑fixed phase residuals,these indicators are derived directly from the float PPP solution and provide a unified measure of SSR product errors,regardless of whether the ambiguities remain float or are subsequently fixed.Furthermore,by leveraging the spatial common‑mode characteristics of the SSR product errors across a wide‑area network,the method derives the corrections to mitigate product error.After correction,the ambiguity‑float phase residuals serve as a unified quality indicator applicable to both ambiguity‑fixed and ambiguity‑float SSR products,enabling reliable quality assessment and anomaly detection.Validation using one month of real‑time SSR products from CNES demonstrates that the proposed method significantly improves the availability and reliability of SSR products.Compared with traditional monitoring methods based on ambiguity‑fixed phase residuals,the proposed method achieves a comparable and slightly higher ambiguity fixing rate(95.56%versus 92.83%),while significantly reducing the incorrect fixing rate from 0.69 to 0.09%.This improvement substantially mitigates the positioning degradation caused by incorrect ambiguity fixing,reducing the three‑dimensional Root Mean Square Error(RMSE)from 15.1 to 4.6 cm. 展开更多
关键词 Real‑time PPP Ambiguity fixing SSR product errors Ambiguity deviations Phase residuals Quality monitoring
Phase error of binary fringe from defocusing projection 认领 引用
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作者 QIAO Nao-sheng CAO Bin-fang 《中国光学（中英文）》 EI CAS CSCD 北大核心 2026年第4期954-961,共8页
Due to the nonlinear effects produced by the actual defocusing projection system,which affect the accuracy of phase measurement,the phase error of binary fringe defocusing projection was studied.Based on the analysis ... Due to the nonlinear effects produced by the actual defocusing projection system,which affect the accuracy of phase measurement,the phase error of binary fringe defocusing projection was studied.Based on the analysis of the current study status in the field,an expression for the intensity distribution of deformed fringe pattern signal in nonlinear systems is given,and the reasons for both high-order spectra components occurrence and their mixing with the fundamental frequency components,resulting in spectra overlapping,are analyzed.Defocus the projector to remove the higher-order harmonic components in the spectra domain and filter out one of the fundamental frequency components.An inverse Fourier transform was then performed on the spectra to obtain the expression of fringe intensity in the spatial domain.The continuous phase containing continuous signals was obtained using the phase-shift algorithm and phase unwrapping,and the expression for phase error after unwrapping in actual measurement systems was derived.The correct analysis of the basic principles has been verified through simulation and experiments.The simulation results indicate that the errors value obtained by the method mentioned in this paper are 34.51%for the binary fringe defocusing method,44.83%for sampling method of Ref.[1],and 67.83%for method of self-correction method of Ref.[10],respectively.The experiment results indicate that the phase recovered by using our method has good effects,and the corresponding phase error is relatively small. 展开更多
关键词 phase measurement defocusing projection system nonlinear phase-shifting phase error
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Preserving subnanometer-scale ranging precision in advanced multiwavelength interferometry via elimination of error magnification 认领 引用
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作者 RUITAO YANG JINXUAN WU +8 位作者 HAO SUN HAISU LV TUO XU FEIFEI YAN XIANG TIAN HONGXING YANG YISI DONG HAIJIN FU PENGCHENG HU 《Photonics Research》 SCIE EI CAS CSCD 2026年第7期2772-2782,共11页
In this study,we comprehensively reveal the error magnification mechanism in multiwavelength interferometry(MWI)for absolute distance measurement.An ideal linear relationship(ILR)between the phases of two wavelengths ... In this study,we comprehensively reveal the error magnification mechanism in multiwavelength interferometry(MWI)for absolute distance measurement.An ideal linear relationship(ILR)between the phases of two wavelengths is introduced.The phase measurement error in the orthogonal direction of the ILR is considerably magnified.To eliminate this error magnification,a coordinate transformation method is proposed to project the measured phase onto the ILR.Experimental results show that the measured Allan deviation decreases from 6.7μm to 0.9 nm at an averaging time of 8μs,reaching 22 pm at an averaging time of 40 ms.This advanced MWI approach enables subnanometer-scale high-precision,microsecond-scale high-speed absolute distance measurements without the need for additional hardware components,offering remarkable potential for future space missions and advanced manufacturing,such as synthetic aperture radars and segmented-mirror optical telescopes. 展开更多
关键词 coordinate transformation method phase measurement allan deviation de absolute distance measurementan error magnification multiwavelength interferometry mwi ideal linear relationship ilr subnanometer scale ranging
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Acute liver failure caused by amino acid or organic acid related inborn errors of metabolism 认领 引用
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作者 Ying Zhou Chi Chen Xin Yang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2026年第1期112-114,共3页
Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].... Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].Toxic intermediates will be produced due to the dysfunction of biochemical pathways.The liver is responsible for many essential metabolic processes,therefore it becomes one of the most severely affected organ by metabolic diseases[3].Early onset of liver disorders in IEMs includes jaundice,hepatomegaly,splenomegaly,ascites,hepatic encephalopathy,and liver failure[4].In infants and young children under 3 years old with acute liver failure(ALF),IEMs account for 18.9%-43%[5]. 展开更多
关键词 biochemical pathway toxic intermediates metabolic diseases early acute liver failure inborn errors metabolism iems organic acid dysfunction distinct enzyme metabolic processestherefore metabolic pathways
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Lagged effects of risk factors on the disability of older adults:A distributed lag non-linear model approach 认领 引用 被引量：1
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作者 Yitong Mao Zhiting Guo +2 位作者 Wen Gao Yuping Zhang Jingfen Jin 《International Journal of Nursing Sciences》 CSCD 2026年第1期53-60,I0004,I0005,共8页
Objectives This study aimed to explore the lagged and cumulative effects of risk factors on disability in older adults using distributed lag non-linear models(DLNMs).Methods We utilized data from the China Health and ... Objectives This study aimed to explore the lagged and cumulative effects of risk factors on disability in older adults using distributed lag non-linear models(DLNMs).Methods We utilized data from the China Health and Retirement Longitudinal Study(CHARLS).After feature selection via Elastic Net Regularization,we applied DLNMs to evaluate the lagged effects of risk factors.Disability was defined as the presence of any difficulties in basic activities of daily living(BADL).The cumulative relative risk(CRR)was calculated by summing the lag-specific risk estimates,representing the cumulative disability risk over the specified lag period.Effect modifications and sensitivity analyses were also performed.Results This study included a total of 2,318 participants.Early-phase lag factors,such as the difficulty in stooping(CRR=3.58;95%CI:2.31-5.55;P<0.001)and walking(CRR=2.77;95%CI:1.39-5.55;P<0.001),exerted the strongest effects immediately upon occurrence.Mid-phase lag factors,such as arthritis(CRR=1.51;95%CI:1.10-2.06;P=0.001),showed a resurgence in disability risk within 2-3 years.Late-phase lag factors,including depressive symptoms(CRR=2.38;95%CI:1.30-4.35;P<0.001)and elevated systolic blood pressure(CRR=1.64;95%CI:1.06-2.79;P=0.02),exhibited significant long-term cumulative risks.Conversely,grip strength(CRR=0.80;95%CI:0.54-0.95;P=0.02)and social participation(CRR=0.89;95%CI:0.73-0.99;P=0.04)were significant protective factors.Conclusions The findings underscore the importance of tailored interventions that account for various lag characteristics of different factors to effectively mitigate disability risk.Future studies should explore the underlying biological and sociological mechanisms of these lagged effects,identify intervention strategies that target risk factors with different lagged patterns,and evaluate their effectiveness. 展开更多
关键词 Ageing Disability Distributed lag non-linear models Nusing Risk factors
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Forecast errors of tropical cyclone track and intensity by the China Meteorological Administration from 2013 to 2022 认领 引用 被引量：1
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作者 Huanmujin Yuan Hong Wang +2 位作者 Yubin Li Kevin K.W.Cheung Zhiqiu Gao 《Atmospheric and Oceanic Science Letters》 CAS CSCD 2026年第1期72-77,共6页
This study presents a comprehensive evaluation of tropical cyclone(TC)forecast performance in the western North Pacific from 2013 to 2022,based on operational forecasts issued by the China Meteorological Administratio... This study presents a comprehensive evaluation of tropical cyclone(TC)forecast performance in the western North Pacific from 2013 to 2022,based on operational forecasts issued by the China Meteorological Administration.The analysis reveals systematic improvements in both track and intensity forecasts over the decade,with distinct error characteristics observed across various forecast parameters.Track forecast errors have steadily decreased,particularly for longer lead times,while error magnitudes have increased with longer forecast lead times.Intensity forecasts show similar progressive enhancements,with maximum sustained wind speed errors decreasing by 0.26 m/s per year for 120 h forecasts.The study also identifies several key patterns in forecast performance:typhoon-grade or stronger TCs exhibit smaller track errors than week or weaker systems;intensity forecasts systematically overestimate weaker TCs while underestimating stronger systems;and spatial error distributions show greater track inaccuracies near landmasses and regional intensity biases.These findings highlight both the significant advances in TC forecasting capability achieved through improved modeling and observational systems,and the remaining challenges in predicting TC changes and landfall behavior,providing valuable benchmarks for future forecast system development. 展开更多
关键词 Forecast error Tropical cyclone Track Intensity
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