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Application of Fuzzy Inference System in Gas Turbine Engine Fault Diagnosis Against Measurement Uncertainties 被引量:1
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作者 Shuai Ma Yafeng Wu +1 位作者 Zheng Hua Linfeng Gou 《Chinese Journal of Mechanical Engineering》 2025年第1期62-83,共22页
Robustness against measurement uncertainties is crucial for gas turbine engine diagnosis.While current research focuses mainly on measurement noise,measurement bias remains challenging.This study proposes a novel perf... Robustness against measurement uncertainties is crucial for gas turbine engine diagnosis.While current research focuses mainly on measurement noise,measurement bias remains challenging.This study proposes a novel performance-based fault detection and identification(FDI)strategy for twin-shaft turbofan gas turbine engines and addresses these uncertainties through a first-order Takagi-Sugeno-Kang fuzzy inference system.To handle ambient condition changes,we use parameter correction to preprocess the raw measurement data,which reduces the FDI’s system complexity.Additionally,the power-level angle is set as a scheduling parameter to reduce the number of rules in the TSK-based FDI system.The data for designing,training,and testing the proposed FDI strategy are generated using a component-level turbofan engine model.The antecedent and consequent parameters of the TSK-based FDI system are optimized using the particle swarm optimization algorithm and ridge regression.A robust structure combining a specialized fuzzy inference system with the TSK-based FDI system is proposed to handle measurement biases.The performance of the first-order TSK-based FDI system and robust FDI structure are evaluated through comprehensive simulation studies.Comparative studies confirm the superior accuracy of the first-order TSK-based FDI system in fault detection,isolation,and identification.The robust structure demonstrates a 2%-8%improvement in the success rate index under relatively large measurement bias conditions,thereby indicating excellent robustness.Accuracy against significant bias values and computation time are also evaluated,suggesting that the proposed robust structure has desirable online performance.This study proposes a novel FDI strategy that effectively addresses measurement uncertainties. 展开更多
关键词 Performance-based fault diagnosis Gas turbine engine Fuzzy inference system measurement uncertainty Regression and classification
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Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements
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作者 Peng Li Meifeng Cai +2 位作者 Shengjun Miao Yuan Li Yu Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期39-48,共10页
Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stre... Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution method.The results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with depth.There is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and messy.Moreover,there is no obvious relationship between the rock quality designation(RQD)and depth.The maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same depth.In addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data. 展开更多
关键词 overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification
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A centroid measurement method based on 3D scanning 被引量:1
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作者 HE Xin LI Zhen 《Journal of Measurement Science and Instrumentation》 2025年第2期186-194,共9页
The centroid coordinate serves as a critical control parameter in motion systems,including aircraft,missiles,rockets,and drones,directly influencing their motion dynamics and control performance.Traditional methods fo... The centroid coordinate serves as a critical control parameter in motion systems,including aircraft,missiles,rockets,and drones,directly influencing their motion dynamics and control performance.Traditional methods for centroid measurement often necessitate custom equipment and specialized positioning devices,leading to high costs and limited accuracy.Here,we present a centroid measurement method that integrates 3D scanning technology,enabling accurate measurement of centroid across various types of objects without the need for specialized positioning fixtures.A theoretical framework for centroid measurement was established,which combined the principle of the multi-point weighing method with 3D scanning technology.The measurement accuracy was evaluated using a designed standard component.Experimental results demonstrate that the discrepancies between the theoretical and the measured centroid of a standard component with various materials and complex shapes in the X,Y,and Z directions are 0.003 mm,0.009 mm,and 0.105 mm,respectively,yielding a spatial deviation of 0.106 mm.Qualitative verification was conducted through experimental validation of three distinct types.They confirmed the reliability of the proposed method,which allowed for accurate centroid measurements of various products without requiring positioning fixtures.This advancement significantly broadened the applicability and scope of centroid measurement devices,offering new theoretical insights and methodologies for the measurement of complex parts and systems. 展开更多
关键词 centroid measurement mass characteristic parameter 3D scanning 3D point cloud data no specialized positioning fixtures multi-point weighing method
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Accurate Measurements and Error Analysis of Bi_(2)Te_(3)-Based Low-Temperature Thermoelectrics
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作者 Jie Zhang Yixuan Ge +9 位作者 Minhua Huang Xiaohan Qin Chao Xin Linhan Wang Wenfeng Du Tianbo Lu Huaizhou Zhao Wenjie Liang Yongjun Cao Guodong Li 《Chinese Physics Letters》 2025年第5期100-116,共17页
The accurate characterization of thermoelectric properties at low temperatures is crucial for the development of high-performance thermoelectric cooling devices. While measurement errors of thermoelectric properties a... The accurate characterization of thermoelectric properties at low temperatures is crucial for the development of high-performance thermoelectric cooling devices. While measurement errors of thermoelectric properties at temperatures above room temperature have been extensively discussed, there is a lack of standard measurement protocols and error analyses for low-temperature transport properties. In this study, we present a measurement system capable of characterizing all three key thermoelectric parameters, i.e., Seebeck coefficient, electrical conductivity, and thermal conductivity, for a single sample across a temperature range of 10 K to 300 K. We investigated six representative commercial Bi_(2)Te_(3)-based samples(three N-type and three P-type). Using an error propagation model, we systematically analyzed the measurement uncertainties of the three intrinsic parameters and the resulting thermoelectric figure of merit. Our findings reveal that measurement uncertainties for both N-type and P-type Bi_(2)Te_(3)-based materials can be effectively maintained below 5% in the temperature range of 40 K to 300 K. However, the uncertainties increase to over 10% at lower temperatures, primarily due to the relatively smaller values of electrical resistivity and Seebeck coefficients in this regime. This work establishes foundational data for Bi_(2)Te_(3)-based thermoelectric materials and provides a framework for broader investigations of advanced low-temperature thermoelectrics. 展开更多
关键词 measurement system thermoelectric parameters low temperature measurements thermoelectric properties thermoelectric cooling devices error analyses standard measurement protocols characterization thermoelectric properties
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Measurement of emissivity with a new grey body and novel IR thermal sensor dubbed TMOS
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作者 Moshe Avraham Shlomi Bouscher +2 位作者 Jonathan Nemirovsky Yael Nemirovsky 《红外与毫米波学报》 北大核心 2025年第1期17-24,共8页
The concept of emissivity has been with the scientific and engineering world since Planck formulated his blackbody radiation law more than a century ago.Nevertheless,emissivity is an elusive concept even for ex⁃perts.... The concept of emissivity has been with the scientific and engineering world since Planck formulated his blackbody radiation law more than a century ago.Nevertheless,emissivity is an elusive concept even for ex⁃perts.It is a vague and fuzzy concept for the wider community of engineers.The importance of remote sensing of temperature by measuring IR radiation has been recognized in a wide range of industrial,medical,and environ⁃mental uses.One of the major sources of errors in IR radiometry is the emissivity of the surface being measured.In real experiments,emissivity may be influenced by many factors:surface texture,spectral properties,oxida⁃tion,and aging of surfaces.While commercial blackbodies are prevalent,the much-needed grey bodies with a known emissivity,are unavailable.This study describes how to achieve a calibrated and stable emissivity with a blackbody,a perforated screen,and a reliable and linear novel IR thermal sensor,18 dubbed TMOS.The Digital TMOS is now a low-cost commercial product,it requires low power,and it has a small form factor.The method⁃ology is based on two-color measurements,with two different optical filters,with selected wavelengths conform⁃ing to the grey body definition of the use case under study.With a photochemically etched perforated screen,the effective emissivity of the screen is simply the hole density area of the surface area that emits according to the blackbody temperature radiation.The concept is illustrated with ray tracing simulations,which demonstrate the approach.Measured results are reported. 展开更多
关键词 BLACKBODY grey body graybody cavity blackbody extended area blackbody EMISSIVITY IR thermometry remote temperature measurement
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Measurement and Characterization of Micro Corner-Cube Reflectors Array Using Coherent Denoising Interference and Physical Model-Based Neural Network
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作者 Xinlan Tang Lingbao Kong +4 位作者 Zhenzhen Ding Yuhan Wang Bo Wang Huixin Song Yanwen Shen 《Chinese Journal of Mechanical Engineering》 2025年第3期61-76,共16页
In modern industrial design trends featuring with integration,miniaturization,and versatility,there is a growing demand on the utilization of microstructural array devices.The measurement of such microstructural array... In modern industrial design trends featuring with integration,miniaturization,and versatility,there is a growing demand on the utilization of microstructural array devices.The measurement of such microstructural array components often encounters challenges due to the reduced scale and complex structures,either by contact or noncontact optical approaches.Among these microstructural arrays,there are still no optical measurement methods for micro corner-cube reflector arrays.To solve this problem,this study introduces a method for effectively eliminating coherent noise and achieving surface profile reconstruction in interference measurements of microstructural arrays.The proposed denoising method allows the calibration and inverse solving of system errors in the frequency domain by employing standard components with known surface types.This enables the effective compensation of the complex amplitude of non-sample coherent light within the interferometer optical path.The proposed surface reconstruction method enables the profile calculation within the situation that there is complex multi-reflection during the propagation of rays in microstructural arrays.Based on the measurement results,two novel metrics are defined to estimate diffraction errors at array junctions and comprehensive errors across multiple array elements,offering insights into other types of microstructure devices.This research not only addresses challenges of the coherent noise and multi-reflection,but also makes a breakthrough for quantitively optical interference measurement of microstructural array devices. 展开更多
关键词 Microstructural arrays measurement Optical measurement Coherent denoising Neural network Multi-reflection
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Recommended electrochemical measurement protocol for oxygen evolution reaction
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作者 Chao Wu Ying Tang +5 位作者 Anqi Zou Junhua Li Haoyan Meng Feng Gao Jiagang Wu Xiaopeng Wang 《DeCarbon》 2025年第2期24-49,共26页
Developing highly active and stable oxygen evolution reaction(OER)catalysts necessitates the establishment of a comprehensive OER catalyst database.However,the absence of a standardized benchmarking protocol has hinde... Developing highly active and stable oxygen evolution reaction(OER)catalysts necessitates the establishment of a comprehensive OER catalyst database.However,the absence of a standardized benchmarking protocol has hindered this progress.In this work,we present a systematic protocol for electrochemical measurements to thoroughly evaluate the activity and stability of OER electrocatalysts.We begin with a detailed introduction to constructing the electrochemical system,encompassing experimental setup and the selection criteria for electrodes and electrolytes.Potential contaminants originating from electrolytes,cells,and electrodes are identified and their impacts are discussed.We also examine the effects of external factors,such as temperature,magnetic fields,and natural light,on OER measurements.The protocol outlines operational mechanisms and recommended settings for various electrochemical techniques,including cyclic voltammetry(CV),potentiostatic electrochemical impedance spectroscopy(PEIS),Tafel slope analysis,and pulse voltammetry(PV).We summarize existing evaluation methodologies for assessing intrinsic activities and long-term stabilities of catalysts.Based on these discussions,we propose a comprehensive protocol for evaluating OER electrocatalysts’performance.Finally,we offer perspectives on advancing OER catalysts from laboratory research to industrial applications. 展开更多
关键词 Electrochemical measurement Oxygen evolution reaction Intrinsic activities STABILITIES Protocols for OER measurement
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AARPose:Real-time and accurate drogue pose measurement based on monocular vision for autonomous aerial refueling
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作者 Shuyuan WEN Yang GAO +3 位作者 Bingrui HU Zhongyu LUO Zhenzhong WEI Guangjun ZHANG 《Chinese Journal of Aeronautics》 2025年第6期552-572,共21页
Real-time and accurate drogue pose measurement during docking is basic and critical for Autonomous Aerial Refueling(AAR).Vision measurement is the best practicable technique,but its measurement accuracy and robustness... Real-time and accurate drogue pose measurement during docking is basic and critical for Autonomous Aerial Refueling(AAR).Vision measurement is the best practicable technique,but its measurement accuracy and robustness are easily affected by limited computing power of airborne equipment,complex aerial scenes and partial occlusion.To address the above challenges,we propose a novel drogue keypoint detection and pose measurement algorithm based on monocular vision,and realize real-time processing on airborne embedded devices.Firstly,a lightweight network is designed with structural re-parameterization to reduce computational cost and improve inference speed.And a sub-pixel level keypoints prediction head and loss functions are adopted to improve keypoint detection accuracy.Secondly,a closed-form solution of drogue pose is computed based on double spatial circles,followed by a nonlinear refinement based on Levenberg-Marquardt optimization.Both virtual simulation and physical simulation experiments have been used to test the proposed method.In the virtual simulation,the mean pixel error of the proposed method is 0.787 pixels,which is significantly superior to that of other methods.In the physical simulation,the mean relative measurement error is 0.788%,and the mean processing time is 13.65 ms on embedded devices. 展开更多
关键词 Autonomous aerial refueling Vision measurement Deep learning REAL-TIME LIGHTWEIGHT ACCURATE Monocular vision Drogue pose measurement
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Consistent fusion for distributed multi-rate multi-sensor linear systems with unknown correlated measurement noises
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作者 Peng WANG Hongbing JI +1 位作者 Yongquan ZHANG Zhigang ZHU 《Chinese Journal of Aeronautics》 2025年第7期389-407,共19页
This study investigates a consistent fusion algorithm for distributed multi-rate multi-sensor systems operating in feedback-memory configurations, where each sensor's sampling period is uniform and an integer mult... This study investigates a consistent fusion algorithm for distributed multi-rate multi-sensor systems operating in feedback-memory configurations, where each sensor's sampling period is uniform and an integer multiple of the state update period. The focus is on scenarios where the correlations among Measurement Noises(MNs) from different sensors are unknown. Firstly, a non-augmented local estimator that applies to sampling cases is designed to provide unbiased Local Estimates(LEs) at the fusion points. Subsequently, a measurement-equivalent approach is then developed to parameterize the correlation structure between LEs and reformulate LEs into a unified form, thereby constraining the correlations arising from MNs to an admissible range. Simultaneously, a family of upper bounds on the joint error covariance matrix of LEs is derived based on the constrained correlations, avoiding the need to calculate the exact error cross-covariance matrix of LEs. Finally, a sequential fusion estimator is proposed in the sense of Weighted Minimum Mean Square Error(WMMSE), and it is proven to be unbiased, consistent, and more accurate than the well-known covariance intersection method. Simulation results illustrate the effectiveness of the proposed algorithm by highlighting improvements in consistency and accuracy. 展开更多
关键词 Distributed multi-rate multisensor system Sensor data fusion Correlated measurement noise Equivalent measurement Consistent method
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Bayesian phase difference estimation based on single-photon projective measurement
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作者 Xu-Hao Yu Ying Wei +7 位作者 Ran Yang Wen-Hui Song Yingning Miao Wei Zhou Xinhui Li Xiaoqin Gao Yan-Xiao Gong Shi-Ning Zhu 《Chinese Physics B》 2025年第7期89-93,共5页
The estimation of quantum phase differences plays an important role in quantum simulation and quantum computation,yet existing quantum phase estimation algorithms face critical limitations in noisy intermediate-scale ... The estimation of quantum phase differences plays an important role in quantum simulation and quantum computation,yet existing quantum phase estimation algorithms face critical limitations in noisy intermediate-scale quantum(NISQ)devices due to their excessive depth and circuit complexity.We demonstrate a high-precision phase difference estimation protocol based on the Bayesian phase difference estimation algorithm and single-photon projective measurement.The iterative framework of the algorithm,combined with the independence from controlled unitary operations,inherently mitigates circuit depth and complexity limitations.Through an experimental realization on the photonic system,we demonstrate high-precision estimation of diverse phase differences,showing root-mean-square errors(RMSE)below the standard quantum limit𝒪(1/√N)and reaching the Heisenberg scaling𝒪(1/N)after a certain number of iterations.Our scheme provides a critical advantage in quantum resource-constrained scenarios,and advances practical implementations of quantum information tasks under realistic hardware constraints. 展开更多
关键词 Bayesian phase difference estimation single-photon projection measurement Heisenberg limit quantum information quantum state engineering and measurements
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Graph Based Two-Phase Procedure for Phasor Data Concentrator Planning in Wide Area Measurement System of Smart Grid
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作者 Ma Hailong Duan Tong +2 位作者 Yi Peng Jiang Yiming Zhang Jin 《China Communications》 2025年第11期291-304,共14页
The phasor data concentrator placement(PDCP)in wide area measurement systems(WAMS)is an optimization problem in the communication network planning for power grid.Instead of using the traditional integer linear program... The phasor data concentrator placement(PDCP)in wide area measurement systems(WAMS)is an optimization problem in the communication network planning for power grid.Instead of using the traditional integer linear programming(ILP)based modeling and solution schemes that ignore the graph-related features of WAMS,in this work,the PDCP problem is solved through a heuristic graphbased two-phase procedure(TPP):topology partitioning,and phasor data concentrator(PDC)provisioning.Based on the existing minimum k-section algorithms in graph theory,the k-base topology partitioning algorithm is proposed.To improve the performance,the“center-node-last”pre-partitioning algorithm is proposed to give an initial partition before the k-base partitioning algorithm is applied.Then,the PDC provisioning algorithm is proposed to locate PDCs into the decomposed sub-graphs.The proposed TPP was evaluated on five different IEEE benchmark test power systems and the achieved overall communication performance compared to the ILP based schemes show the validity and efficiency of the proposed method. 展开更多
关键词 industrial Internet minimum k-section phasor data concentrator placement phasor measurement unit smart grid topology partitioning wide area measurement system
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Adhesion of 2D Materials: Measurement and Modulation
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作者 Na Li Hongrong Wu +1 位作者 Changwei Sun Junhua Zhao 《Acta Mechanica Solida Sinica》 2025年第2期252-274,共23页
Two-dimensional(2D)materials are promising for next-generation electronic devices and systems due to their unique physical properties.The interfacial adhesion plays a vital role not only in the synthesis,transfer and ... Two-dimensional(2D)materials are promising for next-generation electronic devices and systems due to their unique physical properties.The interfacial adhesion plays a vital role not only in the synthesis,transfer and manipulation of 2D materials but also in the manufacture,integration and performance of the functional devices.However,the atomic thickness and limited lateral dimensions of 2D materials make the accurate measurement and modulation of their interfacial adhesion energy challenging.In this review,the recent advances in the measurement and modulation of the interfacial adhesion properties of 2D materials are systematically combed.Experimental methods and relative theoretical models for the adhesion measurement of 2D materials are summarized,with their scope of application and limitations discussed.The measured adhesion energies between 2D materials and various substrates are described in categories,where the typical adhesion modulation strategies of 2D materials are also introduced.Finally,the remaining challenges and opportunities for the interfacial adhesion measurement and modulation of 2D materials are presented.This paper provides guidance for addressing the adhesion issues in devices and systems involving 2D materials. 展开更多
关键词 2D materials ADHESION measurement MODULATION
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Risk Indicator Identification for Coronary Heart Disease via Multi-Angle Integrated Measurements and Sequential Backward Selection
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作者 Hui Qi Jingyi Lian Congjun Rao 《Computer Modeling in Engineering & Sciences》 2025年第10期995-1028,共34页
For the past few years,the prevalence of cardiovascular disease has been showing a year-on-year increase,with a death rate of 2/5.Coronary heart disease(CHD)rates have increased 41%since 1990,which is the number one d... For the past few years,the prevalence of cardiovascular disease has been showing a year-on-year increase,with a death rate of 2/5.Coronary heart disease(CHD)rates have increased 41%since 1990,which is the number one disease endangering human health in the world today.The risk indicators of CHD are complicated,so selecting effective methods to screen the risk characteristics can make the risk predictionmore efficient.In this paper,we present a comprehensive analysis ofCHDrisk indicators fromboth data and algorithmic levels,propose a method for CHDrisk indicator identification based on multi-angle integrated measurements and Sequential Backward Selection(SBS),and then build a risk prediction model.In the multi-angle integrated measurements stage,mRMR(Maximum Relevance Minimum Redundancy)is selected from the angle of feature correlation and redundancy of the dataset itself,SHAPRF(SHapley Additive exPlanations-Random Forest)is selected from the angle of interpretation of each feature to the results,and ARFS-RF(Algorithmic Randomness Feature Selection Random Forest)is selected from the angle of statistical interpretation of classification algorithm to measure the degree of feature importance.In the SBS stage,the features with low scores are deleted successively,and the accuracy of LightGBM(Light Gradient Boosting Machine)model is used as the evaluation index to select the final feature subset.This new risk assessment method is used to identify important factors affecting CHD,and the CHD dataset from the Kaggle website is used as the study subject.Finally,11 features are retained to construct a risk assessment indicator system for CHD.Using the LightGBM classifier as the core evaluationmetric,ourmethod achieved an accuracy of 0.8656 on the Kaggle CHD dataset(4238 samples,16 initial features),outperforming individual feature selection methods(mRMR,SHAP-RF,ARFS-RF)in both accuracy and feature reduction.This demonstrates the novelty and effectiveness of our multi-angle integrated measurement approach combined with SBS in building a concise yet highly predictive CHD risk model. 展开更多
关键词 CHD multi-angle integrated measurements SBS LightGBM
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Assessment of the Accuracy and Consistency of GNSS RTK Measurements Based on Private Continuously Operating Reference Stations(CORS)in Nairobi
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作者 Sammy Mwangi Matara David N.Siriba +2 位作者 John B.K.Kiema Sammy M.Musyoka Eliud Obanda 《International Journal of Geosciences》 2025年第11期837-849,共13页
The advancement of Global Navigation Satellite System(GNSS)technology has enhanced navigation and positioning accuracy,reliability,and availabil-ity.In Kenya,private organizations have installed CORS to support positi... The advancement of Global Navigation Satellite System(GNSS)technology has enhanced navigation and positioning accuracy,reliability,and availabil-ity.In Kenya,private organizations have installed CORS to support position ing and navigation services,allowing users to access GNSS RTK corrections for survey and mapping projects.However,the accuracy and consistency of GNSS RTK measurements from private CORS remain unverified,which this study aimed to address.A study in Nairobi,Kenya,examined the accuracy and consistency of private CORS by comparing GNSS RTK measurements over stable Survey of Kenya(SoK)control points using published coordinates as a reference.Large vertical coordinate value discrepancies(8.5 m-11 m)and relatively smaller horizontal coordinate value discrepancies(0.3 m-2.4 m)were observed.The discrepancies arise because the private CORS operate on an independent datum,not integrated with the Survey of Kenya(SoK)geo detic control network.The proximity of control points to CORS(less than 30 km)had minimal impact on measurement accuracy.To ensure accuracy and consistency,it is recommended that private CORS be integrated into the national grid,enhancing the reliability of GNSS RTK measurements for di verse survey and mapping applications.Alternatively,users relying on private CORS must localize or perform a site calibration of their rover receivers using at least three known control points to align their measurements with the Na-tional Grid. 展开更多
关键词 GNSS CORS National Grid RTK measurements
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Effect of quantum measurement errors on witnessing network topology
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作者 Shu-Yuan Yang Kan He Ming-Xing Luo 《Chinese Physics B》 2025年第9期38-46,共9页
The fragility and stochastic behavior of quantum sources make it crucial to witness the topology of quantum networks.Most previous theoretical methods are based on perfect assumptions of quantum measurements.In this w... The fragility and stochastic behavior of quantum sources make it crucial to witness the topology of quantum networks.Most previous theoretical methods are based on perfect assumptions of quantum measurements.In this work,we propose a method to witness network topology under imperfect assumptions of quantum measurements.We show that the discrimination between star and triangle networks depends on the specific error tolerances of local measurements.This extends recent results for witnessing the triangle network[Phys.Rev.Lett.132240801(2024)]. 展开更多
关键词 quantum network quantum measurement ERROR
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China’s High-Quality Technology Innovation:Scenario Narrative and Measurement System
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作者 Chen Qiangyuan Zhao Haoyun +1 位作者 Lin Sitong Shen Yu 《China Economist》 2025年第1期2-28,共27页
The world today is undergoing disruptive,transformative shifts driven by a new wave of technological revolutions and industrial changes.In this context,a central question for China’s innovation-driven development str... The world today is undergoing disruptive,transformative shifts driven by a new wave of technological revolutions and industrial changes.In this context,a central question for China’s innovation-driven development strategy is how to effectively identify and measure high-quality technological innovations.Drawing on the stylized facts and scenario narrative of China’s technological landscape,this paper proposes a framework and measurement system for evaluating high-quality technological innovations.While China’s top-level design for technological innovation is guided by policy documents,the increasing number of enterprises applying for“high-tech enterprise”status has coincided with a decline in the quality of patent filings.In response,this paper first underscores the challenges and necessity of measuring the quality of technological innovations.Second,we introduce the high-quality technological innovation indicators and employ them to assess the quality of tech innovations at the firm level,utilizing an approach that combines analogical narrative,gene coding,text analysis,semantic logic,and a database of granted invention patents in China.Third,we examine the systematic and individual biases inherent in citation counts,a commonly used indicator,under specific contexts,and employ a granular instrumental variable approach to validate the effectiveness of the indicators.Finally,we develop a“family tree”of the indicators and explore their application scenarios through a combination of established and extended indicators.Our findings provide a theoretical foundation for evaluating China’s technological innovation quality,inform policy incentives,and offer insights for academia to apply high-quality technological innovation indicators in different contexts. 展开更多
关键词 Innovation quality technological innovation measurement system family tree
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Issues and Countermeasures in Energy Measurement Management of Thermal Power Enterprises
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作者 Kunyang Li 《Journal of Electronic Research and Application》 2025年第1期134-140,共7页
To promote energy conservation,emission reduction,and sustainable development in thermal power enterprises,this study conducted a detailed analysis of the problems existing in measurement management in these enterpris... To promote energy conservation,emission reduction,and sustainable development in thermal power enterprises,this study conducted a detailed analysis of the problems existing in measurement management in these enterprises and explored targeted solutions.The analysis found that,faced with increasingly stringent environmental protection requirements and urgent needs to improve energy efficiency,thermal power enterprises must address the current issues in energy measurement management.They should actively respond to the national call for energy conservation and emission reduction,continuously optimize energy measurement management processes,improve energy utilization efficiency,reduce unnecessary energy consumption and emissions,and lay a solid foundation for the green transformation and sustainable development of the industry. 展开更多
关键词 Thermal power generation ENTERPRISE ENERGY measurement management
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A novel vector magnetic measurement system calibration method based on geomagnetic variation
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作者 Ji-hao Liu Xi-hai Li +2 位作者 Chao Niu Xiao-niu Zeng Yun Zhang 《Applied Geophysics》 2025年第1期35-42,232,共9页
Vector magnetic measurement is increasingly widely used.In order to improve the accuracy of vector magnetic measurement system on board a vehicle,researchers have proposed various calibration methods.Most of them requ... Vector magnetic measurement is increasingly widely used.In order to improve the accuracy of vector magnetic measurement system on board a vehicle,researchers have proposed various calibration methods.Most of them require altering the magnetic vector in the vehicle coordinate system.Exploring the use of geomagnetic variation to change the geomagnetic vector in the vehicle coordinate system,this paper proposes a novel vector magnetic measurement calibration method.In this method,a vector magnetometer mounted on a vehicle and an accurate vector magnetometer separately measure the geomagnetic field at diff erent locations within the same area.Based on the physical principle that the geomagnetic variation at two nearby locations is equal,the calibration parameters of the magnetometer on the vehicle can be determined through a set of equations containing the measurements from the two magnetometers.The theoretical derivation and simulation experiment results demonstrate the feasibility of this method.Therefore,it can serve as a new alternative calibration method,especially in scenarios where a high degree of accuracy in the estimation of calibration parameters is not required. 展开更多
关键词 vector magnetic measurement CALIBRATION geomagnetic variation
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Exploring recent breakthroughs in robotic biomechanical and electrophysiological measurement tools
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作者 Hui-Yao Shi Si Tang +3 位作者 Jia-Lin Shi Peng Yu Chan-Min Su Lian-Qing Liu 《Biomedical Engineering Communications》 2026年第1期35-47,共13页
Single-cell biomechanics and electrophysiology measuring tools have transformed biological research over the last few decades,which enabling a comprehensive and nuanced understanding of cellular behavior and function.... Single-cell biomechanics and electrophysiology measuring tools have transformed biological research over the last few decades,which enabling a comprehensive and nuanced understanding of cellular behavior and function.Despite their high-quality information content,these single-cell measuring techniques suffer from laborious manual processing by highly skilled workers and extremely low throughput(tens of cells per day).Recently,numerous researchers have automated the measurement of cell mechanical and electrical signals through robotic localization and control processes.While these efforts have demonstrated promising progress,critical challenges persist,including human dependency,learning complexity,in-situ measurement,and multidimensional signal acquisition.To identify key limitations and highlight emerging opportunities for innovation,in this review,we comprehensively summarize the key steps of robotic technologies in single-cell biomechanics and electrophysiology.We also discussed the prospects and challenges of robotics and automation in biological research.By bridging gaps between engineering,biology,and data science,this work aims to stimulate interdisciplinary research and accelerate the translation of robotic single-cell technologies into practical applications in the life sciences and medical fields. 展开更多
关键词 BIOMECHANICS ELECTROPHYSIOLOGY micro-nano manipulation automated cell measurement ROBOTICS
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Assessing Community Resilience:Validating a Universally Applicable Flood Resilience Measurement Framework and Tool
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作者 Stefan Hochrainer-Stigler Adriana Keating +6 位作者 Stefan Velev Dipesh Chapagain Jung-Hee Hyun Finn Laurien Raquel Guimaraes Romain Clercq-Roques Reinhard Mechler 《International Journal of Disaster Risk Science》 2025年第5期891-902,共12页
Understanding and strengthening community-level resilience to natural hazard-induced disasters is critical for the management of adverse impacts of such events and the growth of community well-being.A key gap in achie... Understanding and strengthening community-level resilience to natural hazard-induced disasters is critical for the management of adverse impacts of such events and the growth of community well-being.A key gap in achieving this is limited standardized and validated disaster resilience measurement frameworks that operate at local levels and are universally applicable.The Flood Resilience Measurement for Communities(FRMC)is a foremost tool for community flood resilience assessment.It follows a structured approach to comprehensively assess community flood resilience across five classes of capacities(capitals)to support strategic investment in resilience strengthening initiatives.The FRMC is a further development of an earlier version(the FRMT,the Flood Resilience Measurement Tool).The FRMT has been developed and applied between 2015 and 2017 in 118 flood prone communities across nine countries.It has been validated in terms of content and face validity as well as in terms of reliability.To reduce redundancy and survey eff ort,the FRMC holds a lesser number of indicators(44 versus 88)and has now been applied in over 320 communities across 20 countries.We examine the validation for the revised resilience construct and the new community applications and present a comprehensive overview of the statistical and user validation process and outcomes in both practical and scientific terms.The results confirm the validity,reliability as well as usefulness of the FRMC framework and tool.Furthermore,our approach and results provide insights for other resilience measurement approaches and their validation eff orts.We also present a comprehensive discussion about the dynamic aspects of flood resilience at community level,and the many validation aspects that need to be incorporated both in terms of quantification eff orts as well as usability on the ground. 展开更多
关键词 Community resilience Floods Resilience measurement Standardized tool UNIVERSAL Validation
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