Error Transfer Research Articles

Dynamic artificial neural network model for ultralow temperature prediction in hydrogen storage tank

Hydrogen fuel cell vehicles are gaining popularity as an alternative to electric vehicles. To support their use, research on hydrogen-storage devices and charging stations is being conducted actively. However, high-pressure hydrogen dispensing can lead to a temperature increase and potential explosion hazards. Therefore, maintaining safe hydrogen temperatures during charging is crucial. However, accurately predicting temperature changes in hydrogen heat exchangers is challenging owing to rapidly changing operating conditions and large temperature differences. In this study, we adopt a deep-learning-based artificial neural network for predicting temporal temperature variations in low-temperature hydrogen heat exchangers. Two networks, namely, the deep neural network (DNN) and recurrent neural network (RNN), are constructed with Bayesian optimization based on the experimentally measured data from an ultralow-temperature hydrogen heat exchanger to predict temperature. Both models showed superior prediction accuracies of temperature within 3.11 % of mean absolute error (MAE) and heat transfer rates of the heat exchanger within 2.53 % of MAE. In particular, DNN modeling is recommended as a universal method for predicting the temperature when previous data are known, and RNN modeling is recommended for predicting the temperature for successive actions in a compressed-hydrogen system.

Theory and practice of hull dynamic deformation law and heading angle transfer error correction

In order to meet the demand of high-precision heading angle transmission in the transfer alignment of inertial navigation system on moving base, the analytical function relationship between the hull deformation and the turning angular velocity and angular acceleration was derived by using the classical beam theory based on the analysis of the equivalent load exerted by the hydrodynamic force and inertia force on the hull structure during the turning process under the combined action of the steering rudder moment and wave force. The objective law between the angular motion and the azimuth deformation angle of the hull under the combined action of maneuvering and sea waves was revealed. Finally, the correction coefficients were determined according to the left turn and right turn motions of the hull by using the measured data of the ship in the sea trial during the S-shape maneuvering navigation, and the azimuth deformation angle correction was completed. The results indicated that the application of the Qu's bending deformation correction formula could greatly reduce the influence of the hull flexural deformation on the heading angle accuracy, meet the needs of high-precision heading angle transmission, and fully verify the correctness of the hull azimuth deformation law and the heading angle transmission error correction theory. This theory and method provided technical support for establishing high-precision distributed digital reference in the field of transfer alignment of inertial navigation on moving base and the application of heading angle transfer of other shipborne equipment.

Key Technologies of Collaborative Target Detection between Self-propelled Anti-aircraft Weapons

In the case of a lack of target information, a self-propelled anti-aircraft weapon can complete its own combat functions by using the detection information of other vehicles through detection coordination technology. When using the detection coordination technology to process the detection information of other vehicles into information that can be used by the vehicle, the relative position and attitude of the vehicle and data transmission delay will affect the accuracy of the processed target information. With the system of detection collaborative technology expounded, emphasis is attached to the research on the detection coordination method based on pure angles without considering distance. A mathematical model of detection coordination technology is created, the approximate statistical law of the processed detection coordination information is obtained through the Monte Carlo method, and the influence of various factors on transmission error analyzed. In addition, the polynomial curve fitting method is used for time alignment, and the unscented Kalman filter method based on singular value decomposition adopted to reduce the information transfer error. The simulation results show the the method is effective for that end.

Free-space interferometer design for optical frequency dissemination and out-of-loop characterization below the 10−21-level

For improving the performance of optical frequency dissemination and the resolution of its out-of-loop (OOL) characterization, we investigate a compact free-space interferometer design in which a monolithic assembly forms the reference arm. Two interferometer designs are realized, and their environmental sensitivity is analyzed based on the properties of the materials involved. We elucidate that in these designs the temperature sensitivities of the out-of-loop signal paths are greater than for the reference arm. As the estimated temperature-variation-induced frequency transfer errors are observed to be the relevant limitation, the out-of-loop characterization signal can be regarded as a trustworthy upper limit of the frequency transfer error to a remote place. We demonstrate a fractional frequency transfer uncertainty and OOL characterization resolution of ≤2.7×10−21 over many measurement runs. With a value of (0.23±1.07)×10−22 the weighted mean offset is significantly below the best reported results so far.

Error Budget of Wafer Bonding Alignment System Based on Vision

Abstract Accurate wafer alignment is the key to achieving wafer bonding accuracy. High-precision wafer alignment systems typically use vision to locate the aligned Mark on two wafers, and use complex mechanisms to perform multiple composite movements to achieve functionality, making the coupling effect of multiple types of errors more complex and challenging the error budget of wafer alignment systems. This paper proposes an error budgeting method for such vision based multibody precision systems. This method takes the homogeneous transformation matrix (HTM) method as the core to model the system error and establish two types of error transfer chains. For the error chain involving visual measurement, an analysis method based on geometrical optics is proposed to consider the influence of the position and orientation errors of the optical path components. Then organize the possible error sources in the system and model the parameters of each error based on actual test results. Combined with the process flow, customize the error model for each link. Finally, perform Monte Carlo simulation. Using the aforementioned method to budget errors for a certain configuration of wafer alignment system, main error sources were identified, and accuracy indicators were proposed based on the alignment accuracy requirements of ± 200 nm. The rationality of the error budget conclusion in this study has been verified through experiments on the construction machine.

Research on Error Transfer Model and Simulation of Aircraft Gun Structure

In order to study the influence of structural motion and geometric error on the firing density during the firing of the aircraft gun, based on the multi-body dynamics theory, the structural topology of the aircraft gun was established, and the motion error coordinate relationship was constructed by the firing chain and the support chain of the aircraft gun. Establish motion transformation matrix and error transformation matrix between adjacent volumes. Further, the error transfer model of the aircraft gun firing process is constructed. The transmission law of the muzzle offset error caused during the firing of the aircraft gun is revealed. Then the model is simulated and analyzed, and the parameters such as test position error, motion error and muzzle vibration displacement under different firing rates are identified. Finally, the simulation results are compared with the experimental test results. The results show that the average error rate in the azimuth direction is 3.94%, and the average error rate in the pitch direction is 6.86%. The error rate in the pitch direction is significantly higher than that in the azimuth direction, and the measured offset values are higher than the simulated values, which verifies the validity and correctness of the model. It can meet the engineering design requirements and provide the basis for the structural design and optimization of the aircraft gun.

Numerical investigation on the effect of cylindrical turbulator on performance of corrugated plate-fin heat exchanger

The corrugated fin is one of the common fin types in plate-fin heat exchangers. The corrugated fins can promote fluid turbulence and separate or destroy the boundary layer. To further increase the turbulence of the fluid in the channel, the cylindrical turbulator is innovatively added to the corrugated finned channel, and its effects on heat transfer and flow resistance is investigated by numerical simulation. Moreover, the field synergy theory is used to analyze why the heat transfer effect of the channel is improved after adding the cylindrical turbulator. Considering the heat transfer effect and flow resistance synthetically, the comprehensive performance of the heat transfer channel can be improved by adding the cylindrical turbulator at low Reynolds numbers. Correspondingly, at high Reynolds numbers, adding the cylindrical turbulator will reduce the comprehensive performance. On this basis, the influence of corrugated channel geometric sizes on the heat transfer and flow properties is investigated. The correlations of Reynolds number, Prandtl number and geometric dimension on heat transfer and friction factor is established for different geometrical dimensions. The correctness of the correlation is verified by choosing four models with random geometric dimensions, and the average absolute error of heat transfer and friction factor is 6.45% and 5.53%.

Size-dependent errors in real-time electron density propagation.

Real-time (RT) electron density propagation with time-dependent density functional theory (TDDFT) or Hartree-Fock (TDHF) is one of the most popular methods to model the charge transfer in molecules and materials. However, both RT-TDHF and RT-TDDFT within the adiabatic approximation are known to produce inaccurate evolution of the electron density away from the ground state in model systems, leading to large errors in charge transfer and erroneous shifting of peaks in absorption spectra. Given the poor performance of these methods with small model systems and the widespread use of the methods with larger molecular and material systems, here we bridge the gap in our understanding of these methods and examine the size-dependence of errors in RT density propagation. We analyze the performance of RT density propagation for systems of increasing size during the application of a continuous resonant field to induce Rabi-like oscillations, during charge-transfer dynamics, and for peak shifting in simulated absorption spectra. We find that the errors in the electron dynamics are indeed size dependent for these phenomena, with the largest system producing the results most aligned with those expected from linear response theory. The results suggest that although the RT-TDHF and RT-TDDFT methods may produce severe errors for model systems, the errors in charge transfer and resonantly driven electron dynamics may be much less significant for more realistic, large-scale molecules and materials.

Mode I interlaminar fracture toughness of two-dimensional continuous fiber reinforced ceramic matrix composites using wedge-loaded double cantilever beam method

In this study, the wedge-loaded double cantilever beam (W-DCB) method was applied to evaluate the mode I interlaminar fracture toughness of two-dimensional (2D) continuous fiber-reinforced ceramic matrix composites (CMCs). Based on the elastic foundation theory, a W-DCB model was built and its compliance formula was derived by considering the axial force effect, shear effect, asymmetric propagation, and incomplete interlaminar contact. The friction effect was analyzed and measured using the theory of error transfer and a quasi-in-situ measurement method, respectively. The results reveal that rational selection of the wedge angle and friction coefficient can reduce the friction effect. Meanwhile, the W-DCB formula was comprehensively verified by compliance curves, crack tip behaviors, and the cohesive zone of 2D CMCs, which demonstrates its accuracy in conjunction with the experimental data. Finally, the energy release rate (ERR) of the 2D CMCs calculated using the W-DCB theory was consistent with the measured data.

Terminological collocations in trainee and professional legal translations

Abstract This paper examines how translation trainees deal with verb-noun terminological collocations when translating a legal text into their L2. The learner data is juxtaposed with professional translations of the same text and comparable non-translated documents. The results indicate that a large proportion of learner renditions is attested in the reference corpora. There is also a relatively high convergence between learners’ and experts’ choices and symmetrical variability. Unattested and inadequate equivalents demonstrate a large variability and low frequency of individual items, which suggests a lack of systematic patterns in mistranslations. The inadequacy of learner solutions is mainly caused by the choice of a collocate and results in information transfer and naturalness errors, with the former being more idiosyncratic and the latter more recurrent. In conclusion, we argue for viewing L2 collocational competence through the lens of genre requirements and professional practice rather than dichotomous categories of nativelike and non-nativelike collocations.

Lexical and grammatical errors analysis on Indonesian-English translation of EFL students in Indonesia

This current study aimed to find out lexical and grammatical errors in Indonesian to English translation texts made by Indonesian EFL learners in a private senior high school in Lampung. A qualitative case study design was adopted in this research. Documentation and literature review were used as the research instruments. To obtain the data, the researchers used 15 simple sentences and a short text in Indonesian. A total of 25 students participated as the sample in this research. The results suggested that there was a total of 402 errors made by the students and the students made more grammatical errors than lexical errors. Regardless of the discrepancy of students’ CEFR level, the most frequent errors found in students’ translation were omissions (24.13%), confusion of sense relations (18.16%), misformations (11.44%), and distortions (9.95%). After identifying the errors, the researcher also attempted to describe the possible sources of errors to fill the gap in previous studies. Based on the analysis, the possible factors influencing the errors were transfer of phonological system, transfer of lexico-semantic errors, transfer of morphological elements, transfer of grammatical elements, transfer of stylistic and cultural elements in interlingual errors and communication strategy-based errors and learning strategy-based errors in intralingual errors.

Analysis on quantifiable and controllable assembly technology for aeronautical thin-walled structures

Assembly affects the product's performance and reliability directly. The current assembly method based on geometric deviation quantity controlling, cannot guarantee the physical performance for complex aeronautical thin-walled structures effectively, such as assembly geometry accuracy and internal interactive stress. And assembly performance controlling is taken as the bottleneck problem that restricting the new aviation requirement of sub-millimeter assembly. In this paper, by proposing the accurate prediction and process-oriented adjustment&controlling strategies on assembly quality, construction on working mode with “quantifiable and controllable” characteristic was proposed, whose aim was to reduce the phenomenon of out-of-tolerance and deformation rebound error, and the ultimate goal is to reduce the uncertainty of assembly performance parameters. At the technical level, the academic development context and existing problems for assembling thin-walled structures were reviewed and analyzed, such as assembly process parameters optimization, assembly error transfer and accumulation, comprehensive adjustment on assembly quality, and virtual assembly simulation validation. Then the key future research trends for aeronautical structure assembly were also put forward, i.e. the force/deformation coordination among multi-type finite units for non-ideal assemblies, the dynamic construction of stiffness matrix for intermediate assemblies considering geometric nonlinearity, the adaptive balance on assembly performance driven by physical modeling and measured data, and the inverse optimization on assembly quality and parameters with intelligent data processing. This paper would lay a solid foundation for achieving the accurate assembly mode with the characteristics of “intelligent/scientific, and active/collaborative controlling on geometric shape and physical performance”, and higher assembly quality and efficiency could also be gained.

Vision-based Mobile Robotic Grinding for Large-scale Workpiece and Its Accuracy Analysis

In this article, a mobile robotic grinding system for large-scale workpiece is proposed. The mobile robot is equipped with a laser sensor, fringe projection scanner, and force-controlled grinding tool. The mobile robot can move in large spaces, calibrate the workpiece accurately, and perform grinding work automatically. A vision-based grinding strategy for the mobile robot is proposed, where the workpiece surface reconstruction and grinding path planning are generated by the measured point clouts. An error index is proposed to analyze the machining accuracy, which can reveal the primary error factor in the error transfer chain. Compared with the mobile robotic grinding based on the global measurement system in (Zhao et al., 2021), the proposed vision-based grinding process requires no precise CAD model of the workpiece and achieves better machining accuracy. Two experiments are conducted in this article, where a wind turbine blade and a part of the aircraft skin have been ground by the mobile robot. Experiments show that the mobile robot under the vision-based grinding strategy is suited for different continues surfaces, and it has great application prospects.

High Precision Mesh-Based Drone Image Stitching Based on Salient Structure Preservation and Regular Boundaries

Addressing problems such as obvious ghost, dislocation, and distortion resulting from the traditional stitching method, a novel drone image-stitching method is proposed using mesh-based local double-feature bundle adjustment and salient structure preservation which aims to obtain more natural panoramas.The proposed method is divided into the following steps. First, reducing parallax error is considered from both global and local aspects. Global bundle adjustment is introduced to minimize global transfer error, and then the local mesh-based feature-alignment model is incorporated into the optimization framework to achieve more accurate alignment. Considering the sensitivity of human eyes to linear structure, the global linear structure that runs through the images obtained by segment fusion is introduced to prevent distortions and align matching line segments better. Rectangular panoramas usually have better visual effects. Therefore, regular boundary constraint combined with mesh-based shape-preserving transform can make the results more natural while preserving mesh geometry. Two new evaluation metrics are also developed to quantify the performance of linear structure preservation and the alignment difference of matching line segments. Extensive experiments show that our proposed method can eliminate parallax and preserve global linear structures better than other state-of-the-art stitching methods and obtain more natural-looking stitching results.

Error simulation of atmospheric scattered radiance and its influence on slant visibility based on the SBDART model and Monte Carlo method.

Atmospheric scattered radiance is an important factor affecting slant visibility measurement in the daytime. This paper explores atmospheric scattered radiance errors and their influence on slant visibility measurements. Considering the difficulty in error synthesis of the radiative transfer equation, an error simulation scheme based on the Monte Carlo method is proposed. An error simulation and error analysis for atmospheric scattered radiance was carried out based on the Santa Barbara DISTORT atmospheric radiative transfer (SBDART) model and the Monte Carlo method. The error in aerosol parameters including the single-scattering albedo (SSA), the asymmetry factor, and the aerosol optical depth (AOD), was simulated by a random number and random error under different normal distributions, and the error influence of aerosol parameters on the error in the solar irradiance and 33-layer atmosphere scattered radiance is discussed in detail. The maximum relative deviations of the output scattered radiance at a certain slant direction are 5.98%, 1.47%, and 2.35%, when SSA, the asymmetry factor, and the AOD obey the normal distribution of (0, 5). The error sensitivity analysis also confirms that the SSA is the most sensitive factor affecting atmospheric scattered radiance and the total solar irradiance. Then, according to the error synthesis theory, we investigated the error transfer effect of three error sources related to the atmosphere based on the contrast ratio between the object and the background. The simulation results show that the error in the contrast ratio caused by solar irradiance and scattered radiance is lower than 6.2% and 2.84%, indicating the main role in contributing to the error transfer of slant visibility. Further, the comprehensive process of the error transfer in slant visibility measurements was demonstrated by a set of lidar experiments and the SBDART model. The results provide a reliable theoretical basis for the measurement of atmospheric scattered radiance and slant visibility, which is of great significance to improve the measurement accuracy of slant visibility.

An Identification Method for the “Effective Coupling Loss Factor” Based on the Hybrid FE-SEA Model

Due to the limitation of the SEA method, the hybrid FE-SEA method has become a powerful tool to solve the medium-frequency “acoustic-vibration problem”. However, in most cases, the solution process of the hybrid FE-SEA model is often accompanied by ill-posed matrix problems, such as the inverse solution of the matrix, and the calculation accuracy is not high, which affects the overall calculation accuracy of the hybrid FE-SEA model. In this paper, the calculation method for the effective coupling matrix of the hybrid FE-SEA model is further improved. Based on the basic parameter solving method of the hybrid FE-SEA model, the hybrid FE-SEA model for three-coupled systems is established. In this paper, the deterministic subsystem and the random subsystem response solving problem in three-coupled systems is studied. The method is extended to the multi-coupled system, and an improved calculation method for the coupling matrix of the hybrid FE-SEA model is proposed. On the basis of the weighted iterative method of the principal element, intermediate variables and error transfer are introduced. The parameter identification problem of the effective coupling loss factor of the hybrid FE-SEA model is solved, which provides a solution for parameter identification of the hybrid FE-SEA model.

Опыт и перспективы автоматизации управления перевозочным процессом скоростного транспорта городских агломераций

The article analyses the technological process of transportation process organization and its control in different systems of urban agglomeration rapid-transit transport. It is presented the generalization of organization technological schemes of transportation process at the compilation of normative documents-schedules of: train traffic, rolling stock turnover, work of locomotive teams. Common features, allowing to share automation and digitization positive experience from one transport systems to another, are revealed. As a typical example for urban agglomeration rapid-transit transport, the work of Moscow Central Ring in data flow diagram notation is considered. It has been shown that the conditions of traffic planning on Moscow Central Ring are analogous to active ones on the subway ring lines. As generalizing notions, there are: mixing, non-parallelism, zoning, non-autonomy. Corresponding illustrative examples are given. Congested experience in the sphere of control automation for transportation process of rapid-transit transport of urban agglomeration is considered on the examples of railway section Nizhniy Novgorod – Uren’ as well as Kaluzhsko-Rizhskaya line of Moscow subway (electrodepots “Kaluzhskoye” and “Sviblovo”). The article describes initial data sets for to perform train traffic schedule, the purpose of its performance has been formulated, limitations, reflecting the links between objects, inside the set of given resources, and limitations, being defined by rules of passenger service, have been revealed. Analysis, pursued in the article, has shown the perspective directions of automated transport systems development on knowledge accumulated bases. As a result of the application of complex approach to the solution of automated control tasks at the use of artificial intelligence technologies and big databases usage, it’s planned to increase the efficiency usage for given resources set, train traffic schedule implementation percentage and others; to reduce information transfer error number as well as those, appeared as a result of negative human factor influence and so on.

Economic Valuation and Benefit Transfer of Restoring the Teesta Riverine Ecosystem

This study seeks to understand the socio-economic and ecological impacts of the hydroelectric power projects along the upper basin of the river Teesta in Sikkim. This study estimates the non-market benefits of restoring the Teesta riverine ecosystem and evaluates the transferability of welfare estimates. This study is a first of its kind undertaken in the Teesta basin which uses a unique dataset of 830 households obtained from the affected regions of the river basin. During the study, nine villages adjacent to the river Teesta, dams, and powerhouses were identified and surveyed. Double bounded dichotomous choice questions were used to elicit willingness to pay (WTP). Both the logistic and normal distribution models were fitted and the results were mostly similar. The median WTP was INR 373.00 and the variables that described the rating on dams, ownership of property, monthly expenditure of the household, informal employment status, and satisfaction about the state of the river Teesta were among the significant variables in the model. The benefit function value transfer estimated was INR 232.00 with the percentage transfer error (PTE) of 61.9%.

Analysis of The Negative Transfer in Chinese Middle School Students Acquisition of English in Lexical Aspect

This paper mainly analyzes the negative transfer issues that Chinese middle school students generally have in their acquisition of English regarding lexical aspect. Data of the research is collected from the designed exercise completed by three middle school students with different English proficiency levels. Concerning all the lexical transfer errors that the students make, collocation and derivation are the two most common types. Regarding collocation, this paper argues that an English word with multiple Chinese equivalents leads to the use of wrong collocations in English. Regarding derivation, this paper finds that the changeable word form of different parts of speech in English causes the wrong use of the word form. In addition, several suggestions are offered to improve the negative transfer in the acquisition of English, which are using English-English dictionary, focusing on the language input, and making contrastive analysis.

How to accurately assess cultural ecosystem services by spatial value transfer? An answer based on the analysis of urban parks

Cultural ecosystem services (CESs) intangibly influence many aspects of public daily life, and when evaluating them, it is difficult to obtain perception data. Spatial value transfer predicts the ecosystem service value of policy sites based on the spatial associations of study sites with services value. This approach has the potential to produce an evaluation without perception data. Previous studies have preliminarily researched the validity and effects of using spatial value transfer to evaluate CESs, but, there are doubts about the transfer performance of indicators, differences among various CES types, and the impact of the physical environment. This study examines the above key points of spatial value transfer in depth, with urban parks as the study area to assess three types of CES values that are closely related to human well-being: aesthetic, historical and recreational value. Two popular indicators, area under the curve statistics and transfer error rate, are used to evaluate transfer performance. The results reveal that historical values have the best transfer performance, and transfer error is lower in transfers from small locations to large locations with environmental variable combinations that include road network, water coverage and attraction distribution. The transfer error rate indicator could not only assess the overall transfer performance but also generate maps to reflect the distribution and value of transfer error. We suggest that more knowledge of minor differences in physical factors and developing specific transfer coefficients for them are necessary to enhance the accuracy of CES evaluation by spatial value transfer.