Error Transfer Research Articles

Transfer accuracy of partially enclosed single hard vacuum-formed trays with 3D-printed models for lingual bracket indirect bonding: A prospective in-vivo study.

This study aims to evaluate the clinical transfer accuracy of partially enclosed single hard vacuum-formed trays based on three-dimensional (3D) printed models for lingual bracket indirect bonding. Thirty-two consecutive patients receiving lingual orthodontic treatment were enrolled. Digital models with ideal bracket positions were 3D-printed, followed by fabrication of partially enclosed single hard vacuum-formed trays. Digital impressions captured actual bracket positions and were compared to the ideal positions. One-tailed t-tests assessed if errors were within clinically acceptable thresholds of 0.5 mm for linear measurements and 2° for angular measurements. Mean bracket transfer errors were 0.052 mm, 0.076 mm, 0.106 mm, 0.795°, 1.344°, and 2.485° for mesiodistal, buccolingual, occlusogingival, rotation, tip, and torque, respectively. Transfer errors were statistically below the clinically acceptable thresholds for all dimensions except torque. Frequencies of acceptable transfer errors were 100%, 100%, 99.3%, 93.1%, 78.3%, and 54.0%, respectively. Partially enclosed single hard vacuum-formed trays with 3D-printed models transfer lingual brackets with high accuracy in the mesiodistal, buccolingual, and occlusogingival dimensions, rotation, and tip. However, the transfer of torque remains questionable.

Precision control mechanism of angular contact ball bearing based on error transfer

Precision control mechanism of angular contact ball bearing based on error transfer

Accuracy Analysis of a Multi-Closed-Loop Truss Antenna with Clearance

Surface accuracy is one of the most crucial indicators for evaluating the performance of a large deployable antenna. It depends on the accuracy of the truss structure of the truss antenna. This paper presents a novel method for accurate analysis of a large deployable truss antenna with 3D joint clearances. The proposed method does not depend on the structure’s style, which is suitable for general multi-closed-loop structures. Firstly, the clearance model of the truss structure is established using a vector description. Then, an error transfer path analysis method is proposed for the multi-closed-loop structure. The distribution probability of the truss antenna’s surface accuracy is also obtained. The efficiency of the method is validated through a numerical example of a planar mechanism with a multi-closed loop. The proposed method is also applied to analyze the surface accuracy of the large deployable antenna with a parabolic cylindrical truss.

Neuro-Adaptive-Based Fixed-Time Composite Learning Control for Manipulators With Given Transient Performance.

This article investigates an adaptive neural network (NN) control technique with fixed-time tracking capabilities, employing composite learning, for manipulators under constrained position error. The first step involves integrating the composite learning method into the NN to address the dynamic uncertainties that inevitably arise in manipulators. A composite adaptive updating law of NN weights is formulated, requiring adherence solely to the relaxed interval excitation (IE) conditions. In addition, for the output error, instead of knowing the initial conditions, this article integrates the error transfer function and asymmetric barrier function to achieve the specific performance for position error in both steady and transient states. Furthermore, the fixed-time control methodology and Lyapunov stability criterion are synergistically employed in order to guarantee the convergence of all signals in the manipulators to a compact neighborhood around the origin within a fixed-time. Finally, numerical simulation and experiments with the Baxter robot results both determine the capability of the NN composite learning technique and fixed-time control strategy.

How to Explain the Huge Differences in Rebound Estimates: A Meta-Regression Analysis of the Literature

Rebound effects are commonly defined as the relative gap between the potential and realized savings in resource use following efficiency improvements or sufficiency changes. While a considerable number of studies quantify rebound effects, empirical estimates vary widely. Reliable information on the magnitude of rebound effects is therefore still lacking, despite being essential to devise and adjust, for example, energy efficiency policies accordingly. Here, we present the first meta-regression analysis of microeconomic rebound effects at the household level, using forty-three studies with 1,118 estimates to determine average rebound effects and to explain heterogeneous empirical findings. We find that the total microeconomic rebound is, on average, about 41%–52%. The variance can be explained by differences in the type of data used, the scenario setup, and the specifics of the rebound estimation in the primary studies. Furthermore, we find only small absolute transfer errors, indicating a good predictability of rebound effects using our meta-regression model.

Calibration experiments for dual-comb IPDA XCO2 measurements using a variable pressure absorption cell

Measuring XCO2, the column-averaged dry-air mixing ratio of CO2 in the atmosphere, is essential for monitoring climate change and guiding mitigation efforts. Integrated Path Differential Absorption (IPDA) is a highly effective XCO2 measurement solution for space-borne lidar. However, the limited number of wavelengths limits its capabilities. IPDA, enhanced with Electro-Optical Frequency Comb (EOFC) technology, offers a robust solution. This study validates IPDA measurements using both asymmetric and symmetric Electro-Optic Dual-Comb Spectroscopy (EO-DCS) systems at 1572 nm. This indoor experimental system does not operate in a true lidar mode, but focuses on IPDA measurements of XCO2 through a transmission-style cell. We achieved atmospheric spectral transmittance by a variable pressure CO2 absorption cell, correlating pressures from 425 to 470 mb to XCO2 of 386.81–447.08 ppm. The XCO2 measurements of asymmetric/symmetric systems both exhibit excellent linearity. Their linear fittings yielded the Root Mean Square Error (RMSE) as low as 0.198/0.064 ppm, and the Mean Absolute Percentage Errors (MAPE) was as low as 0.0386%/0.0140%. This level of measurement performance has never been demonstrated in other works. Accuracy was assessed by comparing IPDA results with a pressure gauge, and precision was confirmed through repetitive measurements (1000 times over 10 min) and Allan variance analysis. Notably, our system operates effectively without frequency stabilization, showing tolerance to laser frequency drift—a significant advantage for IPDA applications. The entire experiment was conducted in a comparison between asymmetric and symmetric systems, especially in the analysis of absorption line residuals. We discuss the error transfer from phase to spectral transmittance and its implications and explained why the residuals in the asymmetric system were larger. These results underscore the superior performance of EO-DCS IPDA in measuring XCO2 and its promising potential for applications. To our knowledge, this is the only DCS IPDA calibration demonstration to date.

Examining negative transfer in Cantonese learners of English as a foreign language: an optimality theory approach to English syllable acquisition

Abstract The contrasting differences that exist in the English and Cantonese phonological systems result in divergent articulatory production between them. This article aims to investigate the negative transfer of Cantonese EFL learners in acquiring English consonant clusters and the constraint rankings of Cantonese and English syllable systems by comparing syllable structures and analyzing experimental statistics. The objective is to elucidate the reasons behind their negative transfer in English syllable acquisition. The research results demonstrated that Cantonese EFL learners found it easier to acquire consonant clusters in the onset position compared to the coda position. Additionally, an increase in consonants in the coda position posed greater difficulties for Cantonese EFL learners. The results also indicated that participants encountered the most problems with deletion, followed by substitution and epenthesis. The OT analysis reveals that the different rankings of faithfulness and markedness constraints in Cantonese and English led to transfer errors.

Modeling and Simulation of Wide-Frequency Characteristics of Electromagnetic Standard Voltage Transformer

To achieve the broadband applicability of standard voltage transformers in “dual high” power systems, an equivalent circuit model of the standard voltage transformer is first established. Using the complex magnetic permeability method and utilizing existing core parameters, the excitation impedance values are obtained. Next, based on the equivalent circuit model, the no-load error function of the standard voltage transformer is analyzed, and through simulation, the no-load error response curve of the standard voltage transformer in the frequency range of 20 Hz to 3000 Hz is derived. The simulation results indicate that within the 20 Hz to 700 Hz range, both the no-load ratio error and the no-load angular error meet the accuracy requirements, with the ratio error within ±0.05% and the angular error within 2′. Additionally, the derivation of the error transfer function demonstrates the correlation between the no-load error values and the number of turns and cross-sectional area of the standard voltage transformer. Simulation results, obtained by increasing and decreasing the number of turns and cross-sectional area by 10%, provide valuable insights for the error compensation and structural design of standard voltage transformers.

Method and Verification of Liquid Cooling Heat Dissipation Based on Internal Heat Source of Airborne Long-Focus Aerial Camera

The traditional passive heat dissipation method has low heat dissipation efficiency, which is not suitable for the heat dissipation of the concentrated heat source inside the long-focal aerial camera, resulting in temperature level changes and temperature gradients in the optical system near the heat source, which seriously affect the imaging performance of the aerial camera. To solve this problem, an active heat dissipation method of liquid cooling cycle is proposed in this paper. To improve the solving efficiency and ensure simulation accuracy, a dynamic boundary information transfer method based on grid area weighting is proposed. The thermal simulation results show that the liquid cooling method reduces the heat source temperature by 70.12%, and the boundary temperature transfer error is 0.015%. The accuracy of thermal simulation is verified by thermal test, and the simulation error is less than 6.44%. In addition, the performance of the optical system is further analyzed, and the results show that the MTF of the optical system is increased from 0.077 to 0.194 under the proposed active liquid cooling cycle heat dissipation method.

A Literature Review of Phonetic Transfer

Phonetic transfer stands out as a vital part of language transfer in second language acquisition. This paper renders a pithy literature review apropos of current studies concerning the phenomenon of phonetic transfer that is arguably contemplated from three phonetic transfer error pertinent aspects: segment, phonology and prosody for the purpose of gaining new insight for the future research.

Thermal Error Transfer Prediction Modeling of Machine Tool Spindle with Self-Attention Mechanism-Based Feature Fusion

Thermal errors affect machining accuracy in high-speed precision machining. The variability of machine tool operating conditions poses a challenge to the modeling of thermal errors. In this paper, a thermal error model based on transfer temperature feature fusion is proposed. Firstly, the temperature information fusion features are built as inputs to the model, which is based on a self-attention mechanism to assign weights to the temperature information and fuse the features. Secondly, an improved direct normalization-based adaptive matrix approach is proposed, updating the background matrix using an autoencoder and reconstructing the adaptive matrix to realize domain self-adaptation. In addition, for the improved adaptive matrix, a criterion for determining whether the working conditions are transferrable to each other is proposed. The proposed method shows high prediction accuracy while ensuring training efficiency. Finally, thermal error experiments are performed on a VCM850 CNC machine tool.

Sensitivity analysis and compensation for tooth surface deviation of spiral bevel gear machine tool

To analyze the quantitative mapping relationship between the geometric errors of the five-axis CNC machine tool and the tooth surface deviation of spiral bevel gears, and identify the key geometric errors that affect the machining deviation of the spiral bevel gear tooth surface, a sensitivity analysis method for tooth surface machining deviation of spiral bevel gear based on screw theory and EFAST method is proposed. Firstly, the machining model of the spiral bevel gear tooth surface based on the five-axis CNC machine tool is established. Then, the geometric error transfer model of the machine tool is established based on the screw theory. Combined with the EFAST global sensitivity analysis method, the key geometric errors that affect tooth surface deviation are identified. Finally, the reliability and effectiveness tests are performed by comparing the results to the local sensitivity analysis method and simulating compensation for the key geometric errors. The result of compensation shows that the tooth surface deviation is reduced significantly according to global sensitivity analysis. The feasibility of applying sensitivity analysis to control the tooth surface deviation of spiral bevel gears has been demonstrated.

Design and parameter optimization of solid-surface antenna parallel mechanism constructed by multi-loop spatial coupling units

The optimization of design and structural parameters of solid-surface antennas is crucial for the development of aerospace satellites. In this paper, the study explores an innovative parallel solid-surface antenna mechanism, inspired by the daisy bloom pattern, which realizes the characteristics of Fewer input-More output (Fi-Mo). A single-DOF deployable/foldable spatial multi-loop coupled mechanism model of the bionic daisy solid-surface antenna is established based on the single-axis tilting hinge, RSSR mechanism, and Bennett mechanism. The motion characteristics of the antenna mechanism are analyzed using the topology, position and orientation characteristic (POC) and inverse screw theory. The error transfer law of multi-loop mechanism is derived by the low-layer-loop sequence. The optimal configuration parameter set of the antenna deployment mechanism is determined using the NSGA-II genetic algorithm. Finally, the optimized antenna mechanism is subjected to physical simulation analysis to verify its stability and the accuracy of its deployment path.

Research on Machining Quality Prediction Method Based on Machining Error Transfer Network and Grey Neural Network

Machining quality prediction is the critical link of quality control in parts machining. With the advent of the Industry 4.0 era, intelligent manufacturing and data-driven technologies bring new ideas for quality control in complex machining processes. Quality control is complicated for multi-process, multi-condition, small-batch, and high-precision parts processing requirements. To solve this problem, this paper proposes a machining quality prediction method based on the machining error transfer network and the grey neural network. Initially, by constructing a processing error transfer network, the error transfer law in part processing is described, and the PageRank algorithm and the influence degree of the nodes are used to determine the critical quality features. Additionally, the problem of low prediction accuracy due to small sample data and multiple coupling relationships is solved using the grey neural network algorithm, and a high accuracy prediction of critical quality features is achieved. Finally, the effectiveness and reliability of the method are verified by the case of medium-speed marine diesel engine fuselage processing. The results indicate that this method not only effectively identifies critical quality features in the machining process of complex parts, but it also maintains a high predictive accuracy for these features, even with small samples and limited data.

Innovative feedback approach for high-performance low-voltage current mirror

The paper presents an approach to increase the performance in terms of input and output resistance of a low voltage flipped voltage follower (FVF) based current mirror. The proposed technique consists of substituting the main output transistor with a network of transistors in a feedback arrangement, designed to improve the output resistance. Furthermore, a low saturation onset transistor approach is used to improve the performance. Such an approach also helped in reducing the input resistance of the current mirror, which ranges in ohms. A wide current range of up to 1 mA is achieved at a minimal current transfer error of 0.38 %. This feedback mechanism-based current mirror exhibits an output resistance of 29.61 GΩ, an input resistance of 30.45 Ω, and a bandwidth of 1.464 GHz. The proposed current mirror runs on ±0.5 V supply voltage. The robustness of the proposed circuit is evaluated through process corner analysis, temperature mismatch assessment, and Monte-Carlo simulations. The performance characteristics of the proposed current mirror have been validated and simulated using Cadence Virtuoso and Spectre simulations on 0.18 μm UMC technology. The validation process included both pre-layout and post-layout simulation results.

Design and Optimization of a Cable-Driven Parallel Polishing Robot With Kinematic Error Modeling

Abstract This article presents the design and optimization of a cable-driven parallel polishing robot (CDPPR) with kinematic error modeling and introduces an improved nondominated sorting genetic algorithm II (NSGA-II) for multiobjective optimization. First, the mechanical design and kinematic and static modeling of the CDPPR are conducted. Subsequently, a kinematic error transfer model is established based on the evidence theory by considering the change of exit points of cables, and an error index is derived to measure the accuracy of the robot. Besides, another two performance indices including the workspace and static stiffness are proposed. Thus, a multiobjective optimization model is established to optimize the workspace, static stiffness, and error index, and an improved NSGA-II is developed. Finally, an experimental scaled prototype of the CDPPR is constructed, and numerical examples and experimental results demonstrate the effectiveness of the improved NSGA-II and the stability of the optimal configuration.

Construction of a Calibration Curve for Lycopene on a Liquid-Handling Platform─Wider Lessons for the Development of Automated Dilution Protocols.

Liquid-handling is a fundamental operation in synthetic biology─all protocols involve one or more liquid-handling operations. It is, therefore, crucial that this step be carefully automated in order to unlock the benefits of automation (e.g., higher throughput, higher replicability). In the paper, we present a study, conducted at the London Biofoundry at SynbiCITE, that approaches liquid-handling and its reliable automation from the standpoint of the construction of the calibration curve for lycopene in dimethyl sulfoxide (DMSO). The study has important practical industrial applications (e.g., lycopene is a carotenoid of industrial interest, DMSO is a popular extractant). The study was also an effective testbed for the automation of liquid-handling. It necessitated the development of flexible liquid-handling methods, which can be generalizable to other automated applications. In addition, because lycopene/DMSO is a difficult mix, it was capable of revealing issues with automated liquid-handling protocols and stress-testing them. An important component of the study is the constraint that, due to the omnipresence of liquid-handling steps, errors should be controlled to a high standard. It is important to avoid such errors propagating to other parts of the protocol. To achieve this, a practical framework based on regression was developed and utilized throughout the study to identify, assess, and monitor transfer errors. The paper concludes with recommendations regarding automation of liquid-handling, which are applicable to a large set of applications (not just to complex liquids such as lycopene in DMSO or calibration curves).

Legal Protection for Bank Customers for Bank Fund Transfer Errors

Legal Protection for Bank Customers for Bank Fund Transfer Errors

IVF laboratory management through workflow-based RFID tag witnessing and real-time information entry

BackgroundDual-person inspection in IVF laboratories cannot fully avoid mix-ups or embryo transfer errors, and data transcription or entry is time-consuming and redundant, often leading to delays in completing medical records.MethodsThis study introduced a workflow-based RFID tag witnessing and real-time information entry platform for addressing these challenges. To assess its potential in reducing mix-ups, we conducted a simulation experiment in semen preparation to analyze its error correction rate. Additionally, we evaluated its impact on work efficiency, specifically in operation and data entry. Furthermore, we compared the cycle costs between paper labels and RFID tags. Finally, we retrospectively analyzed clinical outcomes of 20,424 oocyte retrieval cycles and 15,785 frozen embryo transfer cycles, which were divided into paper label and RFID tag groups.ResultsThe study revealed that comparing to paper labels, RFID tag witnessing corrected 100% of tag errors, didn’t affect gamete/embryo operations, and notably shorten the time of entering data, but the cycle cost of RFID tags was significantly higher. However, no significant differences were observed in fertilization, embryo quality, blastocyst rates, clinical pregnancy, and live birth rates between two groups.ConclusionsRFID tag witnessing doesn’t negatively impact gamete/embryo operation, embryo quality and pregnancy outcomes, but it potentially reduces the risk of mix-ups or errors. Despite highly increased cost, integrating RFID tag witnessing with real-time information entry can remarkably decrease the data entry time, substantially improving the work efficiency. This workflow-based management platform also enhances operational safety, ensures medical informational integrity, and boosts embryologist’s confidence.

Ionospheric contributions to the excess power in high-redshift 21-cm power-spectrum observations with LOFAR

ABSTRACT The turbulent ionosphere causes phase shifts to incoming radio waves on a broad range of temporal and spatial scales. When an interferometer is not sufficiently calibrated for the direction-dependent ionospheric effects, the time-varying phase shifts can cause the signal to decorrelate. The ionosphere’s influence over various spatiotemporal scales introduces a baseline-dependent effect on the interferometric array. We study the impact of baseline-dependent decorrelation on high-redshift observations with the Low Frequency Array (LOFAR). Data sets with a range of ionospheric corruptions are simulated using a thin-screen ionosphere model, and calibrated using the state-of-the-art LOFAR epoch of reionization pipeline. For the first time ever, we show the ionospheric impact on various stages of the calibration process including an analysis of the transfer of gain errors from longer to shorter baselines using realistic end-to-end simulations. We find that direction-dependent calibration for source subtraction leaves excess power of up to two orders of magnitude above the thermal noise at the largest spectral scales in the cylindrically averaged autopower spectrum under normal ionospheric conditions. However, we demonstrate that this excess power can be removed through Gaussian process regression, leaving no excess power above the 10 per cent level for a $5~$ km diffractive scale. We conclude that ionospheric errors, in the absence of interactions with other aggravating effects, do not constitute a dominant component in the excess power observed in LOFAR epoch of reionization observations of the North Celestial Pole. Future work should therefore focus on less spectrally smooth effects, such as beam modelling errors.