Contamination o f wastewater is one of the rising global issues, and several studies are being conducted to perform efficient treatment processes with cost-effective methods. In this study, sugarcane bagasse was used ...
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Contamination o f wastewater is one of the rising global issues, and several studies are being conducted to perform efficient treatment processes with cost-effective methods. In this study, sugarcane bagasse was used as biomass to extract silica (Si) and biochar (BC) and was used further as fillers for aerogel formation with polyvinyl alcohol (PVA) polymer to eliminate Congo red dye from the solution. A batch study was conducted in each case, and the efficiency of dye removal, by different aerogel PVA, PVA-Si, and PVA-BC was studied. Experimental parameters were varied to analyze the effect of the various parameters in each case. The highest removal was 94.98% using PVA-Si aerogel at 300 min with 10 mg/L initial concentration of Congo red, pH 7, and temperature 30 degrees C. The adsorption capacity of Congo red was 29.49 mg/g by PVA-Si aerogel. The characterization of the aerogel showed the occupancy of various functional groups, modification in crystallographic structure, and surface alteration of aerogels. The analysis for the study of kinetics exhibited that the process of adsorption fitted the pseudo-second-order reaction for all the aerogels and also the thermodynamics data demonstrated that the adsorption process was spontaneous and endothermic. Also, from the isotherm modeling, it was observed that the process best fitted with the Freundlich isotherm model.
With the increasing complexity of industrial systems, the frequency of simultaneous faults within these systems is also on the rise, posing a challenge to traditional fault diagnosis methods that rely solely on sensor...
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With the increasing complexity of industrial systems, the frequency of simultaneous faults within these systems is also on the rise, posing a challenge to traditional fault diagnosis methods that rely solely on sensor data. To this end, a novel simultaneous fault diagnosis method for the whole process from data feature extraction to diagnosis model construction is proposed in this article. First, a multi-feature fusion feature extraction method integrating cloud model (CM) and dynamic-inner principal component analysis (DiPCA) is proposed, termed CM-DiPCA, which effectively captures the hidden uncertainties and dynamic characteristics embedded in the fault signals, thereby improving the ability of the diagnosis model to identify and distinguish various fault modes. Subsequently, a dual stochastic configuration network (dualSCN) framework is constructed to identify the fault category while determining the number of faults, significantly enhancing the self-adaptive capabilities and modeling efficiency of the diagnostic model. Moreover, considering the potential correlation between single and simultaneous faults, the CM-based overlap degree (OD) calculation is introduced into dualSCN, thereby reducing the adverse effects predicted only from a probabilistic perspective. The experimental results show that the proposed method exhibits advantages in identifying simultaneous faults and modeling efficiency compared with the existing methods.
Groundwater contamination risk mapping constitutes an important component of groundwater management and quality control. In the present study, we describe a method for such mapping that is more suitable for arid regio...
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Groundwater contamination risk mapping constitutes an important component of groundwater management and quality control. In the present study, we describe a method for such mapping that is more suitable for arid regions than other methods developed in previous work. Specifically, we integrate machine learning tools, interpolation and process-based models with a modified version of DRASTIC-AHP to evaluate groundwater vulnerability to nitrate contamination, and to map this contamination in Jiroft plain, Iran. The DRASTIC model provides a tool for evaluating aquifer vulnerability by using seven parameters related to the hydrogeological setting (depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone and hydraulic conductivity), while the criteria ratings and weights of these parameters are evaluated by means of an analytic hierarchy process (AHP). However, to obtain the risk map, the model predictions related to groundwater vulnerability are combined here with a contamination hazard map, which we estimate by applying ensemble modeling. This modeling builds on the occurrence probability predicted by means of a modeling framework that is based on generalized linear modeling (GLM), flexible discriminant analysis (FDA) and support vector machine (SVM). We find that the application of our ensemble modeling to predicting groundwater contamination in Jiroft plain leads to better results (AUC = 0.916, Kappa = 0.89, MSE = 0.18 and RMSE = 0.11) compared to the separated employment of the various machine learning (ML) methods, i.e., either SVM (AUC = 0.847, Kappa = 0.86, MSE = 0.19 and RMSE = 0.29), GLM (AUC = 0.829, Kappa = 0.81, MSE = 0.23 and RMSE = 0.37) or FDA (AUC = 0.816, Kappa = 0.8, MSE = 0.26 and RMSE = 0.42). Our integrated modeling framework provides an assessment of both regional patterns of groundwater contamination and an estimate of contamination impacts based on socio-environmental variables, being particularly suitable for appl
Serving as a dedicated process analytical technology (PAT) tool for biomass monitoring and control, the capacitance probe, or dielectric spectroscopy, is showing great potential in robust pharmaceutical manufacturing,...
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Serving as a dedicated process analytical technology (PAT) tool for biomass monitoring and control, the capacitance probe, or dielectric spectroscopy, is showing great potential in robust pharmaceutical manufacturing, especially with the growing interest in integrated continuous bioprocessing. Despite its potential, challenges still exist in terms of its accuracy and applicability, particularly when it is used to monitor cells during stationary and decline phases. In this study, data pre-processing methods were first evaluated through cross-validation, where the first-order derivative emerged as the most effective method to diminish variability in prediction accuracy across different training datasets. Subsequently, a segmented adaptive partial least squares (SA-PLS) model was developed, and its accuracy and universality were demonstrated through several validation studies using different clones and culture processes. Furthermore, a real-time viable cell density (VCD) auto-control system in perfusion culture was established, where the VCD was maintained around the target with notable precision and robustness. This model enhanced the monitoring capabilities of capacitance-based PAT tools throughout the cultivation, expanded their application in cell-specific automatic control strategies, and contributed vitally to the advancement of continuous manufacturing paradigms.
Manufacturing turbine blades using metal injection molding (MIM) is a complex process that requires precise control over parameters to achieve high dimensional accuracy. Inadequate management of shrinkage, frozen volu...
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Manufacturing turbine blades using metal injection molding (MIM) is a complex process that requires precise control over parameters to achieve high dimensional accuracy. Inadequate management of shrinkage, frozen volume, and volume filled leads to dimensional deviations, resulting in defects or reduced performance of turbine blades in operation. Optimizing these response factors ensures reliable production and high-quality turbine blades. This study investigates the influence of process parameters in metal injection molding by evaluating their significance and interaction. A three-level central composite design (CCD) approach-based response surface methodology analysis was applied to statistically specify the effect of important numerical and categorical process variables: mold temperature, melt temperature, injection time, flow rate on the critical response process output variables concerning product quality, namely shrinkage, frozen volume, and volume filled. By using a face-centered design, a total of 30 simulation data was fitted. analysis of variance (ANOVA) was then performed to assess the significance of factors and their interactions at a 95% confidence level (p < 0.05). Subsequently, empirical models were developed and rigorously validated against the simulation results. The optimum process parameters of the metal part were characterized as follows: mold temperature of 15 degrees C, 138 degrees C of melt temperature, 2.5 s of injection time, and 94 cm3/s flow rate. The results are expected to advance the metal injection molding industry by providing valuable references and enhancing the understanding of the optimization process.
Event data is a collection of recorded events that capture performed actions and observed states of business processes supported by information systems. It describes the times of event occurrences, event types, event ...
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ISBN:
(纸本)9783031758713;9783031758720
Event data is a collection of recorded events that capture performed actions and observed states of business processes supported by information systems. It describes the times of event occurrences, event types, event attributes, and process cases of events identified by one or more objects the events relate to. process mining uses event data to analyze and improve the processes in organizations. These processes are often performed by actors or agents, such as employees, resources, and systems, in different roles within organizations. In this paper, we present Agent System Event data (ASED), a new type of event data that describes business processes as interactions of agents. ASED provides a new scope for analyzing individual agents involved in multiple processes, interactions of agents, and systems of agents that enact the processes. We formalize ASED as a conceptual data model, discuss its dimensional datamodeling aspects, and argue that event data, in general, benefits from dimensional representation. We review existing event data types and discuss the complementary nature of existing models and ASED. Finally, we validate ASED by demonstrating its ability to express existing business process compliance rules, significantly expanding the scope of compliance analysis addressed by existing data models.
The shifted (or two-parameter) exponential distribution is a probability model that is widely used in many practical applications to model time-to-event data. In reliability analysis it has been frequently used for mo...
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The shifted (or two-parameter) exponential distribution is a probability model that is widely used in many practical applications to model time-to-event data. In reliability analysis it has been frequently used for modeling the lifetime of products with a warranty period. In this paper, we propose and study the properties of a run sum chart for monitoring shifted exponential lifetimes in order to detect a change in either or in both process parameters. Using the Markov chain method, we evaluate several performance measures, based on the run length distribution of the proposed chart, and investigate its performance for increasing and/or decreasing shifts in process parameters. The results of an extensive numerical study show that a properly designed run sum chart has an improved detection ability compared to that of a Shewhart-type Max chart for shifted exponential distribution. In addition, the proposed chart can be considered as a viable alternative to the CUSUM-type Max chart for shifted exponential distribution, since for a large number of out-of-control situations it requires approximately the same, if not less, time to detect them. Finally, for supporting the use of the proposed run sum chart in practice, we provide guidelines and empirical rules for selecting the values of its parameters, along with an illustrative numerical example.
Advanced manufacturing processes are often based on complex multiphysics phenomena that are either poorly understood or are computationally too expensive to simulate in the context of process design, control, or plann...
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Advanced manufacturing processes are often based on complex multiphysics phenomena that are either poorly understood or are computationally too expensive to simulate in the context of process design, control, or planning. Traditionally, simplified physics models with prescribed heuristics or purely data-driven surrogate models are used as alternatives in such applications. The concept of physics-informed machine learning (PIML) has been shown to have unique advantages over both of these alternatives in various fields of complex system analysis. In this paper, a new PIML approach is presented to model the geometry of the cut produced by a magnetically assisted laser-induced plasma micro-machining (M-LIPMM) process. This PIML architecture uses a neural network to auto-adapt the parametric boundary condition and physical properties used in a simplified finite difference-based physics model (of 2D heat conduction), as a function of the inputs namely the laser settings. This network also estimates the scaling and shifting parameters used by a convolutional neural network that takes the temperature profile predicted by the simplified heat conduction model to predict the width and depth of the machined cut. Trained on physical experiment data, the PIML approach compares favorably to a pure data-driven neural network model in extrapolation tests, while also providing physical insights (that the latter cannot). The PIML approach also provides an 85% better accuracy overall compared to the simplified physics model with heuristic settings.
Adaptive graph neural networks (AGNNs) have achieved remarkable success in industrial process soft sensing by incorporating explicit features that delineate the relationships between process variables. This article in...
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Adaptive graph neural networks (AGNNs) have achieved remarkable success in industrial process soft sensing by incorporating explicit features that delineate the relationships between process variables. This article introduces a novel GNN framework, termed entropy-regularized ensemble adaptive graph (E(2)AG), aimed at enhancing the predictive accuracy of AGNNs. Specifically, this work pioneers a novel AGNN learning approach based on mirror descent, which is central to ensuring the efficiency of the training procedure and consequently guarantees that the learned graph naturally adheres to the row-normalization requirement intrinsic to the message-passing of GNNs. Subsequently, motivated by multi-head self-attention mechanism, the training of ensembled AGNNs is rigorously examined within this framework, incorporating an entropy regularization term in the learning objective to ensure the diversity of the learned graph. After that, the architecture and training algorithm of the model are then concisely summarized. Finally, to ascertain the efficacy of the proposed E(2)AG model, extensive experiments are conducted on real-world industrial datasets. The evaluation focuses on prediction accuracy, model efficacy, and sensitivity analysis, demonstrating the superiority of E(2)AG in industrial soft sensing applications.
The idea of creating an epoxy-based gradient composition with hardeners of varying activities was proposed to control the exothermic effect during the curing process. Both resin and hardeners in powder form were selec...
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The idea of creating an epoxy-based gradient composition with hardeners of varying activities was proposed to control the exothermic effect during the curing process. Both resin and hardeners in powder form were selected to create a composition appropriate for the production of large-scale products. By modeling the thermal balance in Thermal Simulations software (Netzsch) based on data obtained from Thermokinetics 3 (Netzsch), a comparative analysis of temperature fields in thick-walled polymer samples of non-gradient and gradient compositions was carried out. A single-stage constant heating rate mode was developed to create a controlled gradient of the resin conversion from the inner layers of the part to the outer layers. The polymerization front is created by a certain ratio of hardeners with different reactivities in the layers of the matrix. The use of this method can lead to a reduction in the curing time, the prevention of overheating and a decrease in the residual stresses in the composite part.
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