The behavior of hydrogen absorption in the NdFeB Hydrogen Decrepitation process is affected by the shape of the NdFeB alloy, pressure and temperature curves of the reaction process, which makes the reaction process wi...
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ISBN:
(纸本)9783037858813
The behavior of hydrogen absorption in the NdFeB Hydrogen Decrepitation process is affected by the shape of the NdFeB alloy, pressure and temperature curves of the reaction process, which makes the reaction process with characteristics of nonlinear, time-varying parameters and coupling. In this study, we proposed a state space modeling method to describe the dynamic mechanism model of the hydrogen decrepitation process, and determine the main parameters of the model according to the mass balance, energy balance and kinetic equations. Then implemented the simulation model of the hydrogen absorption dynamic mechanism model using the matlab language. The simulation results were compared with the measured data, which verified the correctness of the model.
In the manufacturing process, process monitoring is very important. Real-time contrast (RTC) control chart outperforms existing monitoring methods. However, the performance of RTC control chart depends on the classifi...
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ISBN:
(纸本)9781577358091
In the manufacturing process, process monitoring is very important. Real-time contrast (RTC) control chart outperforms existing monitoring methods. However, the performance of RTC control chart depends on the classifier. The existing RTC charts use random forest (RF), support vector machine (SVM), or kernel linear discriminant analysis (KLDA) as a classifier. RF classifier can find cause of faults but the performance is lower than others. Therefore, we suggest the data representation method to improve the RF based RTC control chart. Symbolic aggregate approximation (SAX) is famous method to improve the performance of classification and clustering. We convert the input data by using SAX. We change the parameters of SAX such as alphabet size and breakpoints to improve the performance. Experiment shows that represented data is efficient method to improve the performance of RTC control chart.
The report explores process Automation Tool developed using Altair Hyper Works process Manager to automate UPD analysis, post processing of it and plotting the results. Such a tool assists CAE analysis engineer to cap...
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Tank-system is used in the process industry and needs to detect fault early to increase productivity. In recent years, research on fault detection by processing real-time sensing data has been actively conducted. The ...
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ISBN:
(纸本)9781728165301
Tank-system is used in the process industry and needs to detect fault early to increase productivity. In recent years, research on fault detection by processing real-time sensing data has been actively conducted. The early fault detection method makes the system dependable. In this paper, a fault detection method using Support Vector Machine (SVM) combined with ChangeFinder, both are machine learning methods, is proposed, and the effectiveness is confirmed by simulation and experiment.
The modal decomposition based on the spectra of the Koopman operator has gained much attention in various areas such as data science and optimal control, and dynamic mode decomposition (DMD) has been known as a data-d...
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ISBN:
(纸本)9781538613955
The modal decomposition based on the spectra of the Koopman operator has gained much attention in various areas such as data science and optimal control, and dynamic mode decomposition (DMD) has been known as a data-driven method for this purpose. However, there is a fundamental limitation in DMD and most of its variants;these methods are based on the premise that the target system is time-invariant at least within the data at hand. In this work, we aim to compute DMD on time-varying dynamical systems. To this end, we propose a probabilistic model that has factorially switching dynamic modes. In the proposed model, which is based on probabilistic DMD, observation at each time is expressed using a subset of dynamic modes, and the activation of the dynamic modes varies over time. We present an approximate inference method using expectation propagation and demonstrate the modeling capability of the proposed method with numerical examples of temporally-local events and transient phenomena.
Using detailed metrology and modeling, the excimer beam may be completely characterized making it possible to achieve good agreement among various test methods and allowing accurate prediction of the beam performance ...
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ISBN:
(纸本)0819431516
Using detailed metrology and modeling, the excimer beam may be completely characterized making it possible to achieve good agreement among various test methods and allowing accurate prediction of the beam performance in photolithographic and other applications. Full characterization consists of determining the intensity envelope, wavefront error, and detailed speckle structure statistics. The numerical model consists of a series of exact two-dimensional instantaneous representations of the complex amplitude propagated through the beam train, with time varying speckled structure and integration to generate the time-averaged beam envelope. The detailed description provides a means to validate simpler, but more approximate, theories and to determine the limits of accuracy of these simpler methods for various experiment configurations. We also show results of very recent time-resolved experiments of near-field and focal plane profiles.
A program is reported for nuclear reactor control using process computers for the Hungarian Atomic Energy Program in the course of which the first power plant is scheduled for the early 80s. The first results were ach...
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A program is reported for nuclear reactor control using process computers for the Hungarian Atomic Energy Program in the course of which the first power plant is scheduled for the early 80s. The first results were achieved by a hybrid computer system where the control algorithms were tested with an analog machine instead of an actual reactor. These results formed the basis of the present work to operating a 5 Mw nuclear reactor. Initially, a data acquisition system was developed and was commissioned at the end of 1976. Since then the system has been in continual operation for studying man-machine communications of different types; for developing an alarm analysis subsystem; and for preparing the next phase when the computer is due to play an active role in the reactor control. The data acquisition program is described.
Inverse thermal analysis of Ti-6Al-4V friction stir welds is presented that demonstrates application of a methodology using numerical-analytical basis functions and temperature-field constraint conditions. This analys...
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Inverse thermal analysis of Ti-6Al-4V friction stir welds is presented that demonstrates application of a methodology using numerical-analytical basis functions and temperature-field constraint conditions. This analysis provides parametric representation of friction-stir-weld temperature histories that can be adopted as input data to computational procedures for prediction of solid-state phase transformations and mechanical response. These parameterized temperature histories can be used for inverse thermal analysis of friction stir welds having process conditions similar those considered here. Case studies are presented for inverse thermal analysis of friction stir welds that use three-dimensional constraint conditions on calculated temperature fields, which are associated with experimentally measured transformation boundaries and weld-stir-zone cross sections.
A correlation for longitudinal mass flow of dissolved component against degree of concentration polarization has been developed. The developed solution is applicable to tube-side flow and based on the assumptions that...
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A correlation for longitudinal mass flow of dissolved component against degree of concentration polarization has been developed. The developed solution is applicable to tube-side flow and based on the assumptions that the flow is to be isothermal, laminar, incompressible and steady state. Balance equations for viscous and diffusion boundary layers are the core of the model. Integration of these equations over the control volume of the cylindrical configuration has been carried out. This model permits the analysis of the influence of mass flow, bulk concentration, and velocity on the degree of concentration polarization. It can also give mass flow using the degree of concentration polarization as an input variable. The presented solution can be segmented and built into a complicated algorithm of a membrane-based process. The solution does not contain digital integration and permits simulation and analysis of the influence of various factors. The calculated data are included.
In this work, we present (1) a methodology for collecting, evaluating, and utilizing human-annotated data about course syllabi in predictive models of student success, and (2) an empirical analysis of the predictivene...
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ISBN:
(纸本)9781450348706
In this work, we present (1) a methodology for collecting, evaluating, and utilizing human-annotated data about course syllabi in predictive models of student success, and (2) an empirical analysis of the predictiveness of such features as they relate to others in modeling end-of-course grades in traditional higher education courses. We present a two-stage approach to (1) that addresses several challenges unique to the annotation task, and address (2) using variable importance metrics from a series of exploratory models. We demonstrate that the process of supplementing traditional course data with human-annotated data can potentially improve predictive models with information not contained in university records, and highlight specific features that demonstrate these potential information gains.
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