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OPTIMAL ERROR ESTIMATE IN L~∞(J;L^2(Ω)) NORM OF FEM FOR A MODEL FOR COMPRESSIBLE MISCIBLE DISPLACEMENT IN POROUS MEDIA 被引量:2
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作者 程爱杰 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1995年第2期222-236,共15页
We’ll study the FEM for a model for compressible miscible displacement in porous media which includes molecular diffusion and mechanical dispersion in one-dimensional space.A class of vertices-edges-elements interpol... We’ll study the FEM for a model for compressible miscible displacement in porous media which includes molecular diffusion and mechanical dispersion in one-dimensional space.A class of vertices-edges-elements interpolation operator ink is introduced.With the help of ink(not elliptic projection),the optimal error estimate in L∞(J;L2(Ω)) norm of FEM is proved. 展开更多
关键词 Molecular diffusion and mechanical dispersion SINGLE-PHASE displacement Finite element method (FEM) Vertices-edges-elements interpolation Optimal error estimate in L(J L2 (Ω)) norm.
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Medical errors, infection-control breaches and the use of adulterated and misbranded medical devices 被引量:3
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作者 Lawrence F Muscarella 《World Journal of Clinical Infectious Diseases》 2012年第2期13-27,共15页
Several well-publicized cases of improper cleaning,disinfection or sterilization of contaminated reusable medical equipment that posed an increased risk of patientto-patient disease transmission were reported within t... Several well-publicized cases of improper cleaning,disinfection or sterilization of contaminated reusable medical equipment that posed an increased risk of patientto-patient disease transmission were reported within the past few years,resulting in the notification of approximately 20 000 patients.These medical errors,the specific infection-control standards they breached,and assessments of the risk of infection associated with each are discussed.Other topics discussed include the Food and Drug Administration’s(FDA)regulation of medical devices and infection-control products;the use of adulterated,misbranded,and investigational devices;consent decrees and associated Certificates of Medical Necessity;and informed patient consent.Focus is placed on liquid chemical sterilization,its history,and the FDA’s recent censure and discontinuation of a medical device labeled with this claim,namely,the STERIS System 1 processor.Recommendations are provided for healthcare facilities,regulatory agencies,manufacturers of reusable medical devices,and professional healthcare organizations and administrations to improve public health and prevent healthcareassociated infections. 展开更多
关键词 INFECTION CONTROL STERILIZATION Disinfection DISEASE NOTIFICATION Infectious DISEASE transmission Communicable DISEASE CONTROL Decontamination Medical errors Government regulation Equipment and supplies hospital ASEPTIC technique Liquid chemical STERILIZATION
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Human Factor Based Leadership: Critical Leadership Tools to Reduce Burnout and Latent Error in a Time of Accelerating Change 被引量:1
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作者 Michael R. Privitera 《Health》 2019年第9期1224-1245,共22页
The majority of errors in healthcare are from systems factors that create the latent conditions for error to occur. The majority of occupational stressors causing burnout are also the result of systemic factors. Advan... The majority of errors in healthcare are from systems factors that create the latent conditions for error to occur. The majority of occupational stressors causing burnout are also the result of systemic factors. Advances in technology create new levels of stress and expectations on healthcare workers (HCW) with an endless infusion of requirements from multiple authoritative sources that are tracked and monitored. The quality of care and safety of patients is affected by the wellbeing of HCWs who now practice in an environment that has become more complex to navigate, often expending limited neural resource (brainpower) on classifying, organizing, constantly making decisions on how and when they can accomplish what is required(extraneous cognitive load) in addition to direct patient care. New information demonstrates profound biological impact on the brains of those who have burnout in areas that affect the quality and safety of the decisions they make-which affects risk to patients in healthcare. Healthcare administration curriculum currently does not include ways to address these stress-induced problems in healthcare delivery. The science of human factors and ergonomics (HFE) promotes system performance and worker wellbeing. Patient safety is one component of system performance. Since many requirements come without resource to accomplish them, it becomes incumbent upon health system leadership to organize the means for completion of these to minimize the needless loss of brain power diverted away from the delivery of patient care. Human Factor-Based Leadership (HFBL) is an interactive, problem solving seminar series designed for healthcare leaders. The purpose is to provide relevant human factor science to integrate into their leadership and management decisions to make HCWs occupational environment more manageable and sustainable-which makes safer conditions for clinician wellbeing and patient care. After learning the content, a cohort of healthcare leaders believed that adequately addressing HFE in healthcare delivery would significantly reduce clinician burnout and risk of latent errors from upstream leadership decisions. An overview of the content of the seminars is described. Leadership feedback on usability of these seminars is reported. Three HFBL seminars described are Human Factor Relevance in Leadership, Biopsychosocial Approach to Wellness and Burnout, Human Factor Based Leadership: Examples and Applications. 展开更多
关键词 LEADERSHIP BURNOUT LATENT Conditions LATENT error Patient Safety Quality of Care Human Factor Science COGNITIVE Load OCCUPATIONAL Stress Work Environment Healthcare
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Acute liver failure caused by amino acid or organic acid related inborn errors of metabolism
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作者 Ying Zhou Chi Chen Xin Yang 《Hepatobiliary & Pancreatic Diseases International》 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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Parallel Algorithms for Residue Scaling and Error Correction in Residue Arithmetic
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作者 Hao-Yung Lo Ting-Wei Lin 《Wireless Engineering and Technology》 2013年第4期198-213,共16页
In this paper, we present two new algorithms in residue number systems for scaling and error correction. The first algorithm is the Cyclic Property of Residue-Digit Difference (CPRDD). It is used to speed up the resid... In this paper, we present two new algorithms in residue number systems for scaling and error correction. The first algorithm is the Cyclic Property of Residue-Digit Difference (CPRDD). It is used to speed up the residue multiple error correction due to its parallel processes. The second is called the Target Race Distance (TRD). It is used to speed up residue scaling. Both of these two algorithms are used without the need for Mixed Radix Conversion (MRC) or Chinese Residue Theorem (CRT) techniques, which are time consuming and require hardware complexity. Furthermore, the residue scaling can be performed in parallel for any combination of moduli set members without using lookup tables. 展开更多
关键词 Chinese REMAINDER Theorem (CRT) error Correction error Detection Parallel RESIDUE SCALING RESIDUE Number Systems (RNS) TARGET Race Distance (TRD) TARGET Residue-Digit Difference
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A Two-step Estimation Method of Troposphere Delay with Consideration of Mapping Function Errors 被引量:13
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作者 Haopeng FAN Zhongmiao SUN +1 位作者 Liping ZHANG Xiaogang LIU 《Journal of Geodesy and Geoinformation Science》 2020年第1期76-84,共9页
Mapping function errors are usually not taken into consideration, when space geodetic data observed by VLBI, GNSS and some other techniques are utilized to estimate troposphere delay, which could, however, probably br... Mapping function errors are usually not taken into consideration, when space geodetic data observed by VLBI, GNSS and some other techniques are utilized to estimate troposphere delay, which could, however, probably bring non-ignorable errors to solutions. After analyzing the variation of mapping function errors with elevation angles based on several-year meteorological data, this paper constructed a model of this error and then proposed a two-step estimation method of troposphere delay with consideration of mapping function errors. The experimental results indicate that the method put forward by this paper could reduce the slant path delay residuals efficiently and improve the estimation accuracy of wet tropospheric delay to some extent. 展开更多
关键词 TROPOSPHERIC DELAY mapping function errorS Very Long BASELINE Interferometry parameter weighted adjustment European CENTRE for Medium-Range Weather Forecasts
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Preventing diagnostic errors in critical care using millimeter-wave technology:A transformative approach to patient safety
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作者 Andreas G Siamarou 《World Journal of Critical Care Medicine》 2025年第4期223-234,共12页
BACKGROUND Diagnostic errors in critical care settings are a significant challenge,often leading to adverse patient outcomes and increased healthcare costs.Millimeter-wave(mmWave)technology,with its ability to provide... BACKGROUND Diagnostic errors in critical care settings are a significant challenge,often leading to adverse patient outcomes and increased healthcare costs.Millimeter-wave(mmWave)technology,with its ability to provide high-resolution,real-time data,offers a transformative solution to enhance diagnostic accuracy and patient safety.This paper explores the integration of mmWave technology in intensive care units(ICUs)to enable non-invasive monitoring,minimize diagnostic errors,and improve clinical decision-making.By addressing key challenges,including data latency,signal interference,and implementation feasibility,this approach has the potential to revolutionize patient monitoring systems and set a new standard for critical care delivery.The paper discusses the high prevalence of diagnostic errors in medical care,particularly in primary care and ICUs,and emphasizes the need for improvement in diagnostic accuracy.Diagnostic errors are responsible for a significant number of deaths,disabilities,prolonged hospitalizations and delays in diagnosis worldwide.AIM To address this issue,the paper proposes the use of ultrafast wireless medical big data transmission in primary care,specifically in remote smart sensors monitoring devices.It suggests that wireless transmission with a speed up to 100 Gb/s(12.5 Gbytes/s)within a short distance(1-10 meters)is necessary to reduce diagnostic errors.METHODS The method used in the study,includes system design and testing a channel sounder operating at 63.4-64.4 GHz frequency range.The system demonstrated dynamic range of 70 dB,noise level of-110 dBm,and a time resolution of 1 ns.The experiment measured the impulse response of the channel in 36 locations within the primary care/ICU scenario.RESULTS The system was tested in a simulated ICU environment to evaluate the Latency:Assessing the time delay in data transmission and processing.The results of the study showed that the system met the requirements of ICUs,providing excellent latency values.The delay spread and excess delay values were within acceptable limits,indicating successful resolution of ICU requirements.The paper suggests timely deployment of such a system.Impact on data transmission:A 100 MB magnetic resonance imaging scan can be transmitted in approximately 0.008 seconds;A 1 GB scan would take approximately 0.08 seconds;This capability could revolutionize healthcare,enabling real-time remote diagnostics and comparisons with artificial Intelligence models,even in large-scale systems.CONCLUSION The experiment demonstrated the feasibility of using high-speed wireless transmission for improved diagnostics in ICUs,offering potential benefits in terms of reduced errors and improved patient outcomes.The findings are deemed valuable to the medical community and public healthcare systems,and it is suggested further research in this area. 展开更多
关键词 Big data Primary care Diagnostics errors Smart health Internet of medical things mm wave technology Intensive care unit Remote sensors CONSULTATION Vital signs RADIOLOGY TELEMETRY
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Implications of rare neurological disorders and perceptual errors in natural and synthetic consciousness
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作者 Allen D. Allen 《World Journal of Neuroscience》 2013年第4期234-239,共6页
Recent theories on natural and synthetic consciousness overlook the geometric structure necessary for awareness of 3-dimensional space, as strikingly illustrated by left-neglect disorder. Furthermore, awareness of 3-d... Recent theories on natural and synthetic consciousness overlook the geometric structure necessary for awareness of 3-dimensional space, as strikingly illustrated by left-neglect disorder. Furthermore, awareness of 3-dimensional space entails some surprisingly tenacious optical illusions, as demonstrated by an experiment in the text. Awareness of linear time is also crucial and complex. As a consequence, synthetic consciousness cannot be realized by simply intercomnecting a large number of electronic circuits constructed from ordinary chips and transistors. Since consciousness is a subjective experience, there is no sufficient condition for consciousness that can be experimentally confirmed. The most we can hope for is agreement on the necessary conditions for consciousness. Toward that end, this paper reviews some relevant clinical phenomena. 展开更多
关键词 Human Brain CONSCIOUSNESS Artificial CONSCIOUSNESS Clinical NEUROLOGY Fractal Cortex Perceptual errorS NEUROLOGICAL Time EMOTIONAL PRECOGNITION Artificial Sociopath Quantum Mechanical Measurement
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Reduction of Systematic Error in Radiopharmaceutical Activity by Entropy Based Mutual Information
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作者 Palliyakarany T. K. Kumar Toshikazu Takeda 《World Journal of Nuclear Science and Technology》 2012年第1期1-5,共5页
The quality of the radiation dose depends upon the gamma count rate of the radionuclide used. Any reduction in error in the count rate is reflected in the reduction in error in the activity and consequently on the qua... The quality of the radiation dose depends upon the gamma count rate of the radionuclide used. Any reduction in error in the count rate is reflected in the reduction in error in the activity and consequently on the quality of dose. All the efforts so far have been directed only to minimize the random errors in count rate by repetition. In the absence of probability distribution for the systematic errors, we propose to minimize these errors by estimating the upper and lower limits by the technique of determinant in equalities developed by us. Using the algorithm we have developed based on the tech- nique of determinant inequalities and the concept of maximization of mutual information (MI), we show how to process element by element of the covariance matrix to minimize the correlated systematic errors in the count rate of 113 mIn. The element wise processing of covariance matrix is so unique by our technique that it gives experimentalists enough maneuverability to mitigate different factors causing systematic errors in the count rate and consequently the activity of 113 mIn. 展开更多
关键词 Random and Systematic errorS Covariance Matrix Limits for Correlated Elements by DETERMINANT INEQUALITIES Mutual INFORMATION REDUCTION of Systematic errorS by Maximizing Mutual INFORMATION
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Estimation under a Finite Mixture of Exponentiated Exponential Components Model and Balanced Square Error Loss 被引量:1
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作者 Essam K. AL-Hussaini Mohamed Hussein 《Open Journal of Statistics》 2012年第1期28-38,共11页
By exponentiating each of the components of a finite mixture of two exponential components model by a positive parameter, several shapes of hazard rate functions are obtained. Maximum likelihood and Bayes methods, bas... By exponentiating each of the components of a finite mixture of two exponential components model by a positive parameter, several shapes of hazard rate functions are obtained. Maximum likelihood and Bayes methods, based on square error loss function and objective prior, are used to obtain estimators based on balanced square error loss function for the parameters, survival and hazard rate functions of a mixture of two exponentiated exponential components model. Approximate interval estimators of the parameters of the model are obtained. 展开更多
关键词 Finite Mixtures Exponentiated EXPONENTIAL Distribution Maximum Likelihood ESTIMATION Bayes ESTIMATION SQUARE error and BALANCED SQUARE error LOSS Functions Objective Prior
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Performance analysis and design of MIMO-OFDM system using concatenated forward error correction codes 被引量:3
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作者 Arun Agarwal Saurabh N.Mehta 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1322-1343,共22页
This work investigates the performance of various forward error correction codes, by which the MIMO-OFDM system is deployed. To ensure fair investigation, the performance of four modulations, namely, binary phase shif... This work investigates the performance of various forward error correction codes, by which the MIMO-OFDM system is deployed. To ensure fair investigation, the performance of four modulations, namely, binary phase shift keying(BPSK), quadrature phase shift keying(QPSK), quadrature amplitude modulation(QAM)-16 and QAM-64 with four error correction codes(convolutional code(CC), Reed-Solomon code(RSC)+CC, low density parity check(LDPC)+CC, Turbo+CC) is studied under three channel models(additive white Guassian noise(AWGN), Rayleigh, Rician) and three different antenna configurations(2×2, 2×4, 4×4). The bit error rate(BER) and the peak signal to noise ratio(PSNR) are taken as the measures of performance. The binary data and the color image data are transmitted and the graphs are plotted for various modulations with different channels and error correction codes. Analysis on the performance measures confirm that the Turbo + CC code in 4×4 configurations exhibits better performance. 展开更多
关键词 bit error rate (BER) convolutional CODE (CC) forward error correction peak signal to noise ratio (PSNR) Turbo CODE
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FeatherGuard:A Data-Driven Lightweight Error Protection Scheme for DNN Inference on Edge Devices
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作者 Dong Hyun Lee Na Kyung Lee Young Seo Lee 《Computers, Materials & Continua》 2026年第2期2000-2016,共17页
There has been an increasing emphasis on performing deep neural network(DNN)inference locally on edge devices due to challenges such as network congestion and security concerns.However,as DRAM process technology conti... There has been an increasing emphasis on performing deep neural network(DNN)inference locally on edge devices due to challenges such as network congestion and security concerns.However,as DRAM process technology continues to scale down,the bit-flip errors in the memory of edge devices become more frequent,thereby leading to substantial DNN inference accuracy loss.Though several techniques have been proposed to alleviate the accuracy loss in edge environments,they require complex computations and additional parity bits for error correction,thus resulting in significant performance and storage overheads.In this paper,we propose FeatherGuard,a data-driven lightweight error protection scheme for DNN inference on edge devices.FeatherGuard selectively protects critical bit positions(that have a significant impact on DNN inference accuracy)against bit-flip errors,by considering various DNN characteristics(e.g.,data format,layer-wise weight distribution,actually stored logical values).Thus,it achieves high error tolerability during DNN inference.Since FeatherGuard reduces the bit-flip errors based on only a few simple arithmetic operations(e.g.,NOT operations)without parity bits,it causes negligible performance overhead and no storage overhead.Our experimental results show that FeatherGuard improves the error tolerability by up to 6667×and 4000×,compared to the conventional systems and the state-of-the-art error protection technique for edge environments,respectively. 展开更多
关键词 Edge AI DRAM reliability error protection bit-flip error deep neural networks
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Total score of the computer vision syndrome questionnaire predicts refractive errors and binocular vision anomalies
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作者 Mosaad Alhassan Tasneem Samman +5 位作者 Hatoun Badukhen Muhamad Alrashed Balsam Alabdulkader Essam Almutleb Tahani Alqahtani Ali Almustanyir 《International Journal of Ophthalmology(English edition)》 2026年第1期90-96,共7页
AIM:To evaluate the efficacy of the total computer vision syndrome questionnaire(CVS-Q)score as a predictive tool for identifying individuals with symptomatic binocular vision anomalies and refractive errors.METHODS:A... AIM:To evaluate the efficacy of the total computer vision syndrome questionnaire(CVS-Q)score as a predictive tool for identifying individuals with symptomatic binocular vision anomalies and refractive errors.METHODS:A total of 141 healthy computer users underwent comprehensive clinical visual function assessments,including evaluations of refractive errors,accommodation(amplitude of accommodation,positive relative accommodation,negative relative accommodation,accommodative accuracy,and accommodative facility),and vergence(phoria,positive and negative fusional vergence,near point of convergence,and vergence facility).Total CVS-Q scores were recorded to explore potential associations between symptom scores and the aforementioned clinical visual function parameters.RESULTS:The cohort included 54 males(38.3%)with a mean age of 23.9±0.58y and 87 age-matched females(61.7%)with a mean age of 23.9±0.53y.The multiple regression model was statistically significant[R²=0.60,F=13.28,degrees of freedom(DF=17122,P<0.001].This indicates that 60%of the variance in total CVS-Q scores(reflecting reported symptoms)could be explained by four clinical measurements:amplitude of accommodation,positive relative accommodation,exophoria at distance and near,and positive fusional vergence at near.CONCLUSION:The total CVS-Q score is a valid and reliable tool for predicting the presence of various nonstrabismic binocular vision anomalies and refractive errors in symptomatic computer users. 展开更多
关键词 computer vision syndrome refractive errors ACCOMMODATION VERGENCE binocular vision SYMPTOMS
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Bayesian Joint Modelling of Survival Time and Longitudinal CD4 Cell Counts Using Accelerated Failure Time and Generalized Error Distributions 被引量:1
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作者 Markos Abiso Erango Ayele Taye Goshu 《Open Journal of Modelling and Simulation》 2019年第1期79-95,共17页
Survival of HIV/AIDS patients is crucially dependent on comprehensive and targeted medical interventions such as supply of antiretroviral therapy and monitoring disease progression with CD4 T-cell counts. Statistical ... Survival of HIV/AIDS patients is crucially dependent on comprehensive and targeted medical interventions such as supply of antiretroviral therapy and monitoring disease progression with CD4 T-cell counts. Statistical modelling approaches are helpful towards this goal. This study aims at developing Bayesian joint models with assumed generalized error distribution (GED) for the longitudinal CD4 data and two accelerated failure time distributions, Lognormal and loglogistic, for the survival time of HIV/AIDS patients. Data are obtained from patients under antiretroviral therapy follow-up at Shashemene referral hospital during January 2006-January 2012 and at Bale Robe general hospital during January 2008-March 2015. The Bayesian joint models are defined through latent variables and association parameters and with specified non-informative prior distributions for the model parameters. Simulations are conducted using Gibbs sampler algorithm implemented in the WinBUGS software. The results of the analyses of the two different data sets show that distributions of measurement errors of the longitudinal CD4 variable follow the generalized error distribution with fatter tails than the normal distribution. The Bayesian joint GED loglogistic models fit better to the data sets compared to the lognormal cases. Findings reveal that patients’ health can be improved over time. Compared to the males, female patients gain more CD4 counts. Survival time of a patient is negatively affected by TB infection. Moreover, increase in number of opportunistic infection implies decline of CD4 counts. Patients’ age negatively affects the disease marker with no effects on survival time. Improving weight may improve survival time of patients. Bayesian joint models with GED and AFT distributions are found to be useful in modelling the longitudinal and survival processes. Thus we recommend the generalized error distributions for measurement errors of the longitudinal data under the Bayesian joint modelling. Further studies may investigate the models with various types of shared random effects and more covariates with predictions. 展开更多
关键词 ACCELERATED Failure Time BAYESIAN Joint Model CD4 Cell COUNT Generalized error Distribution HIV/AIDS Longitudinal Survival Analysis
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Gap Functions and Error Bounds for Set-Valued Vector Quasi Variational Inequality Problems
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作者 Rachana Gupta Aparna Mehra 《Applied Mathematics》 2017年第12期1903-1917,共15页
One of the classical approaches in the analysis of a variational inequality problem is to transform it into an equivalent optimization problem via the notion of gap function. The gap functions are useful tools in deri... One of the classical approaches in the analysis of a variational inequality problem is to transform it into an equivalent optimization problem via the notion of gap function. The gap functions are useful tools in deriving the error bounds which provide an estimated distance between a specific point and the exact solution of variational inequality problem. In this paper, we follow a similar approach for set-valued vector quasi variational inequality problems and define the gap functions based on scalarization scheme as well as the one with no scalar parameter. The error bounds results are obtained under fixed point symmetric and locally α-Holder assumptions on the set-valued map describing the domain of solution space of a set-valued vector quasi variational inequality problem. 展开更多
关键词 SET-VALUED VECTOR QUASI Variational Inequality Problem GAP FUNCTION Regularized GAP FUNCTION error Bounds Fixed Point Symmetric MAP α-Holder MAP
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Far-Field Pattern Reconstruction from Positioning Errors Affected Near-Field Data Acquired via Helicoidal Scanning
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作者 Francesco D’Agostin Flaminio Ferrara +2 位作者 Claudio Gennarelli Rocco Guerriero Massimo Migliozzi 《Journal of Electromagnetic Analysis and Applications》 2012年第2期60-68,共9页
In this paper, an effective technique to compensate the positioning errors in a near-field—far-field (NF-FF) transformation with helicoidal scanning for elongated antennas is presented and validated both numerically ... In this paper, an effective technique to compensate the positioning errors in a near-field—far-field (NF-FF) transformation with helicoidal scanning for elongated antennas is presented and validated both numerically and experimentally. It relies on a nonredundant sampling representation of the voltage measured by the probe, obtained by considering the antenna as enclosed in a cylinder ended in two half-spheres. An iterative scheme is used to reconstruct the helicoidal NF data at the points fixed by the representation from the acquired irregularly spaced ones. Once the helicoidal data have been retrieved, those needed by a classical NF-FF transformation with cylindrical scanning are efficiently evaluated by using an optimal sampling interpolation algorithm. Some numerical tests, assessing the accuracy of the approach and its stability with respect to random errors affecting the data, are reported. Experimental tests performed at the Antenna Characterization Lab of the University of Salerno further confirm the validity of the proposed technique. 展开更多
关键词 Antenna Measurements Near-FieldFar-Field TRANSFORMATIONS Helicoidal SCANNING Nonredundant Sampling REPRESENTATIONS of Electromagnetic Fields Probe Positioning errors Compensation
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Detection of co-phasing error in segmented mirror based on extended Young’s interferometry combined with Vision Transformer
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作者 LIU Yin-ling YAO Chi +3 位作者 OUYANG Shang-tao WAN Yi-rong CHEN Mo LI Bin 《中国光学(中英文)》 北大核心 2026年第1期205-218,共14页
Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the... Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the monolithic counterpart,the sub-mirrors must maintain precise co-phasing.Piston error critically degrades segmented mirror imaging quality,necessitating efficient and precise detection.To ad-dress the limitations that the conventional circular-aperture diffraction with two-wavelength algorithm is sus-ceptible to decentration errors,and the traditional convolutional neural networks(CNNs)struggle to capture global features under large-range piston errors due to their restricted local receptive fields,this paper pro-poses a method that integrates extended Young’s interference principles with a Vision Transformer(ViT)to detect piston error.By suppressing decentration error interference through two symmetrically arranged aper-tures and extending the measurement range to±7.95μm via a two-wavelength(589 nm/600 nm)algorithm.This approach exploits ViT’s self-attention mechanism to model global characteristics of interference fringes.Unlike CNNs constrained by local convolutional kernels,the ViT significantly improves sensitivity to inter-ferogram periodicity.The simulation results demonstrate that the proposed method achieves a measurement accuracy of 5 nm(0.0083λ0)across the range of±7.95μm,while maintaining an accuracy exceeding 95%in the presence of Gaussian noise(SNR≥15 dB),Poisson noise(λ≥9 photons/pixel),and sub-mirror gap er-ror(Egap≤0.2)interference.Moreover,the detection speed shows significant improvement compared to the cross-correlation algorithm.This study establishes an accurate,robust framework for segmented mirror error detection,advancing high-precision astronomical observation. 展开更多
关键词 segmented mirror co-phasing piston errors ViT Youngs interference principles
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Theoretical Modeling and Compensation of Errors in Industrial Robot Accuracy and Repeatability
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作者 Zhou Yang 《机械工程与设计(中英文版)》 2025年第2期14-17,共4页
Industrial robots are integral to modern manufacturing systems,enabling high precision,high throughput,and flexibility.However,errors in accuracy and repeatability,which arise from a variety of sources such as mechani... Industrial robots are integral to modern manufacturing systems,enabling high precision,high throughput,and flexibility.However,errors in accuracy and repeatability,which arise from a variety of sources such as mechanical wear,calibration issues,and environmental factors,can significantly impact the performance of industrial robots.This paper aims to explore the theoretical modeling of errors in industrial robot systems and propose compensation strategies to enhance their accuracy and repeatability.Key factors contributing to errors,such as kinematic,dynamic,and environmental influences,are discussed in detail.Additionally,the paper explores various compensation techniques,including geometric error compensation,dynamic compensation,and adaptive control approaches.Through the integration of error modeling and compensation methods,industrial robots can achieve improved performance,ensuring higher operational efficiency and product quality.The paper concludes by highlighting the challenges and future research directions for improving the accuracy and repeatability of industrial robots in practical applications. 展开更多
关键词 Industrial Robots ACCURACY REPEATABILITY error Modeling Compensation Strategies Kinematic errors Dynamic errors Adaptive Control
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Insights into Student Perceptions of Error Feedback and Improvement Preferences in Online Programming Education
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作者 Li Zhang Tianze Wang +1 位作者 Jing Jiang Yufei Zhou 《计算机教育》 2026年第3期176-189,共14页
Online programming platforms are popular in programming education.However,there has been no research investigating students’real opinions and expectations of the error feedback mechanisms,leaving educators without a ... Online programming platforms are popular in programming education.However,there has been no research investigating students’real opinions and expectations of the error feedback mechanisms,leaving educators without a solid data foundation when attempting to improve the error feedback mechanisms.This paper makes a survey of 834 students across various programming courses and investigates student perceptions of error feedback mechanisms on online programming platforms.It explores the effectiveness of existing feedback,student satisfaction,and preferences for potential improvements,focusing on automatic error localization and program repair mechanisms.Results reveal a significant portion of students are dissatisfied with current feedback due to its limited informativeness.Students also express a clear demand for stronger feedback mechanisms,such as error localization and repair hints.Nevertheless,they prefer feedback that subtly guides them toward solutions,rather than providing direct and explicit answers,valuing the opportunity to enhance their debugging skills.The findings suggest a need for balanced,educational-focused feedback mechanisms that aid learning while promoting independent problem-solving. 展开更多
关键词 error feedback Online programming education Program error localization Automated program repair
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