Articles de revues sur le sujet « DoE calibration optimization »
Pour voir les autres types de publications sur ce sujet consultez le lien suivant : DoE calibration optimization.
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Consultez les 31 meilleurs articles de revues pour votre recherche sur le sujet « DoE calibration optimization ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Parcourez les articles de revues sur diverses disciplines et organisez correctement votre bibliographie.
1
Stubler, Timo, Matthias Niegl, Martin Förster, Peter E. Pfeffer et Ravi Abhishek. « Development and model-based calibration of the lateral controllers “steer-by-angle” and “steer-by-torque” of a lane keeping assistance system ». Proceedings of the Institution of Mechanical Engineers, Part D : Journal of Automobile Engineering 235, no 8 (24 janvier 2021) : 2136–47. http://dx.doi.org/10.1177/0954407020987437.
Texte intégralRésumé :
Advanced Driver Assistance Systems (ADAS) such as Lane Keeping Assistance (LKA) systems are in the focus of current vehicle developments. Of special interest is the calibration task, which plays an increasingly decisive role in early development stages. At this point it is essential to analyze the pre-calibrated controller concepts by appropriate simulation methods. A software toolchain is introduced, using Model-in-the-Loop (MiL) for the evaluation and calibration of the LKA system. Within, a Design-of-Experiment (DoE) tool is integrated together with the simulation environment. This enables the examination of the two different lateral controller concepts Steer-by-Angle (SbA) and Steer-by-Torque (SbT). Their lateral guidance performance is characterized by Key Performance Indicators (KPI), which are derived from simulation quantities of straight-line and cornering maneuvers. Further, statistical behavior models are generated based on those KPI and controller design variables (DV). The subsequent optimization process leads to high performances of both controllers. In particular, the SbA controller shows higher efficiency under the impact of disturbances as well as the reference reaction with lower settling times. Overall, the achieved lateral guidance performances indicate the potential of both control algorithms in an early development stage. With the software toolchain, a platform for further LKA system calibration and lateral guidance performance optimization is established.
2
Wang, Jun, Lizhong Shen, Yuhua Bi, Shaohua Liu et Mingding Wan. « Power recovery of a variable nozzle turbocharged diesel engine at high altitude by response surface methodology and sequential quadratic programming ». Proceedings of the Institution of Mechanical Engineers, Part D : Journal of Automobile Engineering 233, no 4 (21 février 2018) : 810–23. http://dx.doi.org/10.1177/0954407017753913.
Texte intégralRésumé :
Based on a review of the research methods about diesel engine performance recovery at high altitude and an experimental investigation, by optimizing variable nozzle turbocharger (VNT) and fuel supply system calibration parameters a novel method is proposed to enhance the performance of a turbocharged diesel engine at high altitude. At an altitude of 1920 m, four calibration parameters deeply affecting performance of the diesel engine were selected at the rated power condition, that is, injection quantity, injection timing, injection pressure, and VNT nozzle opening. In order to reduce thermal load of the diesel engine running in the plateau environment, reasonable coded levels of Design of Experiments (DoE) factors were chosen, and an experimental design matrix was selected based on the Box–Behnken design. The interaction effects of the four calibration parameters on engine performance were investigated using the response surface methodology. Power recovery optimization was carried out by means of sequential quadratic programming under a minimum smoke limit and durability constraints. The results show that this performance optimization method can effectively recover engine performance at high altitude. Moreover, it can, to an extent, alleviate the problems such as deterioration of fuel consumption and high thermal load induced by the rise in elevation. With optimized calibration parameters, the rated power of the diesel engine at an altitude of 1920 m proved to be recovered to that at sea level, and there was an increase of brake specific fuel consumption by less than 3% compared with that in the plain area, which met the performance and durability requirements for general turbocharged internal combustion engines at altitudes lower than 2000 m.
3
Huang, Chao-Tsai, Rui-Ting Xu, Po-Hsuan Chen, Wen-Ren Jong et Shia-Chung Chen. « Investigation on the machine calibration effect on the optimization through design of experiments (DOE) in injection molding parts ». Polymer Testing 90 (octobre 2020) : 106703. http://dx.doi.org/10.1016/j.polymertesting.2020.106703.
Texte intégral
4
Di Blasio, Gabriele, Mauro Viscardi et Carlo Beatrice. « DoE Method for Operating Parameter Optimization of a Dual-Fuel BioEthanol/Diesel Light Duty Engine ». Journal of Fuels 2015 (21 janvier 2015) : 1–14. http://dx.doi.org/10.1155/2015/674705.
Texte intégralRésumé :
In recent years, alcoholic fuels have been considered as an alternative transportation biofuel even in compression ignition engines either as blended in diesel or as premixed fuel in the case of dual-fuel configuration. Within this framework, the authors investigated the possibility to improve the combustion efficiency when ethanol is used in a dual-fuel light duty diesel engine. In particular, the study was focused on reducing the HC and CO emissions at low load conditions, acting on the most influential engine calibration parameters. Since this kind of investigation would require a significant number of runs, the statistical design of experiment methodology was adopted to reduce significantly its number. As required by the DoE approach, a set of factors (injection parameters, etc.) were selected. For each of them, two levels “high” and “low” were defined in a range of reasonable values. Combining the levels of all the factors, it was possible to evaluate the effects and the weight of each factor and of their combination on the outputs. The results identified the rail pressure, the pilot, and post-injection as the most influential emission parameters. Significant reductions of unburnt were found acting on those parameters without substantial penalties on the global engine performances.
5
Albers, Albert, Alexander Schwarz, Rolf Hettel et Matthias Behrendt. « Time Efficient Testing of Hybrid Electric Vehicles Using Automated Identificated Physical Model Structures ». Applied Mechanics and Materials 391 (septembre 2013) : 118–22. http://dx.doi.org/10.4028/www.scientific.net/amm.391.118.
Texte intégralRésumé :
Validation and optimization of technical systems are central activities in the product development process. One part of it is the calibration and validation on a level, which covers the whole vehicle. The aspect, that plays the most important role in both validation and optimization, is the driving condition. Especially in the case of hybrid vehicles, state variables like the state of charge (SOC) have great influence on the operating strategy and therefore on assessment criteria.The article’s objective is to present a procedure, which performs the conditioning and brings the planned maneuver into an order, which reduces the total needed conditioning duration. Thereby a lot of time can be saved, according to the type and amount of the possible maneuver and state values. In addition to optimizing the order of conventional maneuver, the procedure can be used to optimize the list of maneuver in a DOE-Plan. Thereby the maneuver of the individual criteria can be re-sorted as well as the designparametervariation. The IPEK-X-in-the-Loop framework (XiL) is the basis for the approach and will be used as a validation environment in an acoustic roller test bench with vehicle-in-the-loop technology.
6
Galindo, José, Héctor Climent, Joaquín de la Morena, David González-Domínguez, Stéphane Guilain et Thomas Besançon. « Experimental and modeling analysis on the optimization of combined VVT and EGR strategies in turbocharged direct-injection gasoline engines with VNT ». Proceedings of the Institution of Mechanical Engineers, Part D : Journal of Automobile Engineering 235, no 10-11 (19 mars 2021) : 2843–56. http://dx.doi.org/10.1177/09544070211004502.
Texte intégralRésumé :
The combination of a growing number of complex technologies in internal combustion engines (ICE) is commonplace, due to the need of complying with the tight pollutant regulations and achieving high efficiencies. Hence the work of calibration engineers is led by a constant increase in degrees of freedom in ICE design. In this research work, a wide analysis on the optimization of combined variable valve timing (VVT) and exhaust gases recirculation (EGR) strategies is developed, in order to reduce fuel consumption in a EURO 6 1.3l 4-stroke 4-cylinder, gasoline, turbocharged, direct-injection engine, also equipped with a variable nozzle turbine (VNT). For that purpose, a methodology which combines 1D engine simulations with limited experimental work was applied. First, the data from 25 experimental tests distributed into three steady engine operating conditions was used to calibrate a 1D model. Then, modeling parametric studies were performed to optimize VVT and EGR parameters. A total of 150 cases were simulated for each operating point, in which VVT settings and EGR rate were varied at iso-air mass flow and iso-intake manifold temperature. The optimization was based on finding the configuration of VVT and EGR systems which maximizes the indicated efficiency. All different cases modeled were also evaluated in terms of pumping and heat losses. Moreover, a deep assessment of instantaneous pressure traces and mass flows in intake and exhaust valves was given, to provide insights about the optimization procedure. Finally, the findings obtained by simulation were compared with the results from a design of experiments (DOE) composed of more than 300 tests, and the impact on engine fuel consumption was analyzed.
7
Tekeste, Mehari Z., Mohammad Mousaviraad et Kurt A. Rosentrater. « Discrete Element Model Calibration Using Multi-Responses and Simulation of Corn Flow in a Commercial Grain Auger ». Transactions of the ASABE 61, no 5 (2018) : 1743–55. http://dx.doi.org/10.13031/trans.12742.
Texte intégralRésumé :
Abstract. Grain augers are primary grain conveying equipment in agriculture. Quantitative prediction of dynamic grain flow in grain augers using discrete element modeling (DEM) has potential to support simulation-based engineering design of grain handling equipment. The objective of this study was to develop a DEM corn model using a multi-response calibration methodology and validation of combine-harvested corn flow in a commercial grain auger. Using a Latin hypercube design of experiment (DOE) sampling from four particle interaction DEM parameters values, 27 DEM simulations were generated for four DEM corn shape approximations (1-sphere, 2-spheres, 5-spheres, and 13-spheres) to create virtual DEM experiments of bucket-discharged and anchor-lifted angle of repose (AOR) tests. A surface meta-model was developed using the DEM interaction parameters as predictor variables, and normalized AOR expressed as a mean square error (MSE), i.e., the sum of square differences between DEM simulations and laboratory-measured AOR. Analysis of the MSE percentiles with lower error differences between DEM simulations and laboratory AOR and the computational effort required per simulation (h per simulation) showed that the 2-spheres DEM model had better performance than the 1-sphere, 5-spheres, and 13-spheres models. Using the best stepwise linear regression models of bucket AOR MSE (R2 of 0.9423 and RMSE of 94.56) and anchor AOR MSE (R2 of 0.5412 and RMSE of 78.02) and a surface profiler optimization technique, an optimized 2-spheres DEM corn model was generated. The DEM predicted AOR with relative errors of 8.5% for bucket AOR and 7.0% for anchor AOR. A DEM grain auger simulation used as a validation step also showed good agreement with the laboratory-measured steady-state mass flow rate (kg s-1) and static AOR (degrees) of corn piled on a flat surface, with DEM prediction relative error ranging from 2.8% to 9.6% and from 8.55% to 1.26%, respectively. Keywords: Corn, DEM, Discharge angle of repose, Discrete element modeling, Grain auger, Lift angle of repose.
8
Korsunovs, Aleksandrs, Felician Campean, Gaurav Pant, Oscar Garcia-Afonso et Efe Tunc. « Evaluation of zero-dimensional stochastic reactor modelling for a Diesel engine application ». International Journal of Engine Research 21, no 4 (29 avril 2019) : 592–609. http://dx.doi.org/10.1177/1468087419845823.
Texte intégralRésumé :
Prediction of engine-out emissions with high fidelity from in-cylinder combustion simulations is still a significant challenge early in the engine development process. This article contributes to this fast evolving body of knowledge by focusing on the evaluation of NO x emission prediction capability of a probability density function–based stochastic reactor engine models for a Diesel engine. The research implements a systematic approach to the study of the stochastic reactor engine model performance, underpinned by a detailed space-filling design of experiments (DoE)-based sensitivity analysis of both external and internal parameters, evaluating their effects on the accuracy in matching physical measurements of both in-cylinder conditions and NO x output. The approach proposed in this article introduces an automatic stochastic reactor engine model calibration methodology across the engine operating envelope, based on a multi-objective optimization approach. This aims to exploit opportunities for internal stochastic reactor engine model parameters tuning to achieve good overall modelling performance as a trade-off between physical in-cylinder measurements accuracy and the output NO x emission predictions error. The results from the case study provide a valuable insight into the effectiveness of the stochastic reactor engine model, showing good capability for NO x emissions prediction and trends, while pointing out the critical sensitivity to the external input parameters and modelling conditions.
9
A. Razak, J., N. Mohamad, M. A. Mahamood, R. Jaafar, I. S. Othman, M. M. Ismail, L. K. Tee, R. Junid et Z. Mustafa. « On the preparation of EPDM-g-MAH compatibilizer via melt-blending method ». Journal of Mechanical Engineering and Sciences 13, no 3 (27 septembre 2019) : 5424–40. http://dx.doi.org/10.15282/jmes.13.3.2019.14.0440.
Texte intégralRésumé :
This paper presents an experimental investigation to determine the optimum composition of maleic anhydride (MAH) and dicumyl peroxide (DCP) as initiator for ethylene-propylene-diene-monomer grafted MAH (EPDM-g-MAH) compatibilizer preparation, using response surface methodology (RSM) approach. EPDM-g-MAH was prepared in the laboratory scale by melt blending method using an internal mixer. For this study, the effects of MAH (2.50 – 7.50 wt.%) and DCP (0.10 – 0.30 wt.%) towards grafting efficiency was determined. Two level full factorial design of experiment (DOE) is applied to establish the relationship between these two independent factors of raw materials. Analysis of variance (ANOVA) and the optimization menu were utilized to decide the raw materials formulation with maximum grafting efficiency. Quantitative analysis based on infra-red (IR) spectral intensity supported by 1H-NMR spectral are used to propose for EPDM-g-MAH grafting mechanism. Standard calibration curve for quantity ratio plot was exponential with R2 = 89.19%. It was found that an optimum about 8.52% of MAF grafting efficiency has been yielded with DCP factor has contributed larger effect at 67.45% of contribution effect. Anhydride stretching of grafted C=O as confirmed by FTIR peak at 1713 cm-1 and 1770 – 1792 cm-1 has responsible for MAH grafting into EPDM rubber. Based on FTIR, 1H-NMR and 2D-COSY spectral analysis, reaction mechanism for EPDM-g-MAH grafting was successfully proposed with two possible termination steps.
10
Vidović, Tino, Ivan Tolj, Gojmir Radica et Natalia Bodrožić Ćoko. « Proton-Exchange Membrane Fuel Cell Balance of Plant and Performance Simulation for Vehicle Applications ». Energies 15, no 21 (31 octobre 2022) : 8110. http://dx.doi.org/10.3390/en15218110.
Texte intégralRésumé :
In this study, a newly developed zero-dimensional electrochemical model was used for modeling and controlling proton-exchange membrane fuel cell (PEMFC) performance. Calibration of the model was performed with measurements from the fuel cell stack. Subsequently, a compressor and a humidifier on the cathode side were sized and added to the existing model. The aim of this work was to model the PEMFC stack and balance of plant (BoP) components in detail to show the influence of operating parameters such as cathode pressure, stack temperature and cathode stoichiometric ratio on the performance and efficiency of the overall system compared to the original model using a newly developed real-time model. The model managed to predict the profile of essential parameters, such as temperature, pressure, power, voltage, etc. The most important conclusions from this particular case are: the cell power output is only slightly changed with the variations in stoichiometric ratio of the cathode side and adding an external compressor is valid only for high current applications, but in those cases, there is 10–22% power gain. Stack temperature is a very influential parameter. Optimal temperatures were determined through design of experiments (DoE) and for this case are in the 40–60 °C range, where for low current applications lower temperatures are better due lower activation loss (8% difference between 80 °C and 40 °C at 20 A current). For high current applications, due to lower ohmic losses, higher temperatures are desirable.
11
Duan, Lei, et Yang Zhang. « Optimization Design in Cooling Channels of Calibrator for Plastic Profile Extrusion Based on Numerical Simulation ». Applied Mechanics and Materials 494-495 (février 2014) : 677–80. http://dx.doi.org/10.4028/www.scientific.net/amm.494-495.677.
Texte intégralRésumé :
Hot plastic profile produced by extrusion die is cooled down and calibrated by calibrator. Therefore, the cooling and calibrating ability of the calibrator directly influence the quality and output of the profile. The key is to design the distribution of cooling channels in calibrator. By analyzing the heat transfer process during cooling in calibrator, the cooling process of plastic profile in calibrator is simulated. Based on the finite element analysis results, the optimization objective is established to obtain the cooling efficiency and uniformity of each node in the profile cross sections of the calibrators exit and finish the optimization design of the cooling channels positions.
12
Jie, Xiran, Bolun Zheng et Boxuan Gu. « Gain and Phase Calibration of Uniform Rectangular Arrays Based on Convex Optimization and Neural Networks ». Electronics 11, no 5 (25 février 2022) : 718. http://dx.doi.org/10.3390/electronics11050718.
Texte intégralRésumé :
A calibration method based on convex optimization (CVX) and neural networks is proposed for the large planar arrays of phased array three-dimensional imaging sonar systems. The method only needs an acoustic calibration source at an unknown position in the far field, and the direction of arrival (DOA) and gain and phase error are jointly estimated. The method uses a CVX algorithm to solve an optimization problem and initially estimates the DOA of the calibration source robustly. Subsequently, according to the estimation results, a neural network is used for fitting to obtain off-grid DOA estimation of the calibration source. Thereafter, spatial matched filtering is performed to obtain the gain and phase residual estimations. The root mean square error (RMSE) of the beam pattern calibrated by the method for uniform planar arrays can reach a value of 4.9542 × 10−5. The experimental results demonstrate the efficiency of the proposed method for gain and phase calibration.
13
Rakhmanov, S. R. « Mathematical simulation of seamless pipes extrusion and rational calibration of die ». Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 77, no 1 (19 janvier 2021) : 70–79. http://dx.doi.org/10.32339/0135-5910-2021-1-70-79.
Texte intégralRésumé :
Technology of seamless pipes production by extrusion enables to deform pipe workpieces made of low-plastic materials. However, low durability of the working instrument restricts the area of the technology application. The purpose of the work was to specify optimal parameters of technological processes of pipes extrusion. Minimization of energy and force parameters of the deformation zone and an increase of once-only metal deformation were accepted as criteria. They will enable to increase the presses productivity, increase durability of working instrument and accuracy of pipes geometric dimensions. A mathematical model of deformation zone and stressed state of pipe workpiece were elaborated. Influence of the die generatrix calibration and deformation zone parameters on the character of energy and force parameters change revealed. Dependence of energy and force parameters on the die calibration and geometric parameters of deformation zone for the press 50 MH was established. The results of mathematical simulation of pipes extrusion showed that along the whole deformation zone length, increase of metal flow speed results in an increase of tangential and normal stresses on the forming mandrel and calibrated die. The task of parametric optimization of die profile (calibration) was accomplished in interpretation of base variation Euler’s task for a determined functional of pipes extrusion. It was established that while the extrusion speed is increasing, the energy and force parameters of the deformation zone are getting pronounced dynamic character. At that, by optimization of die calibration, an increase of the extrusion press 50MH working instruments durability was reached, as follows: dies – by two times, mandrels – by 4 times, container bushes – by 40% and press-washers – by 2 times.
14
Wang, Peng, Yujun Kong et Mingxing Zhang. « Error Self-Calibration Algorithm for Acoustic Vector Sensor Array ». Journal of Sensors 2019 (4 septembre 2019) : 1–10. http://dx.doi.org/10.1155/2019/9052547.
Texte intégralRésumé :
In this paper, the errors of acoustic vector sensor array are classified, the impact factor of each error for the array signal model is derived, and the influence of each type of error on the direction-of-arrival (DOA) estimation performance of the array is compared by Monte Carlo experiments. Converting the directional error and location error to amplitude and phase errors, the optimization model and error self-calibration algorithm for acoustic vector sensor array are proposed. The simulation experiments and field experiment data processing of MEMS vector sensor array show that the proposed self-calibration algorithm has good parameter estimation performance and certain engineering practicability.
15
Wang, Qi Bing, Zhi Ming Wang et An Hua Peng. « Optimization Design of Cooling System of Vacuum Calibrator for Plastics Profile Extrusion ». Advanced Materials Research 168-170 (décembre 2010) : 959–62. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.959.
Texte intégralRésumé :
Plastic profile produced by extrusion die should be cooled down and calibrated by calibrator ,so the proper design of the cooling system in calibrator was very important to the profile quality .The cooling channels in calibrator were preliminarily designed according to target function, and peculiar heterotype optimum designs of the local cooling channels were carried out by means of numerical simulation , the cooling effect was improved obviously ,Based on enterprise resource planning ERP system and parallel project computer aided design/computer aided Engineering CAD/CAE intellectualized data-base network, design for the cooling system was more reasonable, and could meet the demands of customers much better.
16
Guo, Yiduo, Xiaowei Hu, Weike Feng et Jian Gong. « Low-Complexity 2D DOA Estimation and Self-Calibration for Uniform Rectangle Array with Gain-Phase Error ». Remote Sensing 14, no 13 (26 juin 2022) : 3064. http://dx.doi.org/10.3390/rs14133064.
Texte intégralRésumé :
Most subspace-based algorithms need exact array manifold for direction of arrival (DOA) estimation, while, in practical applications, the gain-phases of different array elements are usually inconsistent, degrading their estimation performance. In this paper, a novel low-complexity 2D DOA and gain-phase error estimation algorithm is proposed by adding auxiliary array elements in a uniform rectangular array (URA). Firstly, the URA is modeled as the Kronecker product of two uniform linear arrays (ULAs) to decouple the 2D DOA estimation. Then, several well-calibrated auxiliary array elements are added in the two ULAs, based on which the rotation invariant factor of the URA destroyed by the gain-phase error is reconstructed by solving constrained optimization problems. Lastly, ESPRIT is used to estimate the 2-D DOA and the gain-phase error coefficients. The closed-form expressions of the estimation CRBs are also derived, providing insight into the impact of gain-phase error on DOA estimation. Simulation results are used to validate the effectiveness of the proposed algorithm and the correctness of the theoretical analysis.
17
Zhang, Ron, John Tseng, Hala Shaba, Ellis Chau, Wael Zohni et Laura Mirkarimi. « Thermal Analysis of xFD DRAM Packages Through Simulation and Experimental Validation ». Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2013, DPC (1 janvier 2013) : 001646–80. http://dx.doi.org/10.4071/2013dpc-wp33.
Texte intégralRésumé :
The design optimization for thermal management of systems relies heavily on accurate thermal models of the individual components. Invensas is developing new packaging concepts that provide enhanced and reliable performance electrically, thermally and mechanically. These development efforts use predictive finite element analysis to drive the optimization of package design for improved thermo-mechanical strain and thermal management. Therefore, it is important to validate such models through rigorous experimental thermal measurements. This work represents the 2nd half of our effort in the area of multi-die face-down stack thermal analysis. As was presented last year for the dual die face-down stack analysis, we will present details of our quad die face-down package design, assembly and the thermal test protocols. We will outline our methodologies for measuring thermal performance and achieving tight tolerances in the experimental apparatus as well as guidelines for making appropriate assumptions for associated simulations. We examined JEDEC standard test conditions for natural convection and forced air flow at various air velocities. Comparing values obtained from experimental measurements with simulation data showed results that were within 10% margin in many cases. We will discuss in detail the important calibration protocol and considerations required in the experimental test area for enhanced precision.
18
Gupta, M. « Accurate Simulation of the Four Modes of Post-Die Extrudate Shape Distortion ». International Polymer Processing 36, no 1 (1 mars 2021) : 69–78. http://dx.doi.org/10.1515/ipp-2020-3995.
Texte intégralRésumé :
Abstract A combined flow, thermal and structural analysis is employed to simulate post-die extrudate distortion in different profile dies. All four factors which can cause extrudate distortion, namely, nonuniform exit velocity distribution, extrudate shrinkage, extrudate draw down, and deformed shape of the calibrator or sizer profile, are simulated. To analyze the effect of exit velocity variation on extrudate distortion, the parameterized geometry of a simple profile die is optimized using an extrusion die optimization software. The simulation results presented for a bi-layer profile die successfully demonstrate how gradually changing profile shape in successive calibrators/sizers can be used to simplify the die design for extrusion of complex profiles. The predicted extrudate shape and layer structure for the bi-layer die are found to accurately match with those in the extruded product.
19
Jiang, Xiaoqian, Aditya Menon, Shuang Wang, Jihoon Kim et Lucila Ohno-Machado. « Doubly Optimized Calibrated Support Vector Machine (DOC-SVM) : An Algorithm for Joint Optimization of Discrimination and Calibration ». PLoS ONE 7, no 11 (6 novembre 2012) : e48823. http://dx.doi.org/10.1371/journal.pone.0048823.
Texte intégral
20
Hu, Cheng Liang, Shogo Osaki, Bai Xuan Cai et Mitsuru Aoyama. « Optimization of the Steady Combined Forward and Backward Extrusion Test for Higher Sensitivity to Friction in Cold Forging ». Defect and Diffusion Forum 414 (24 février 2022) : 147–53. http://dx.doi.org/10.4028/p-225h26.
Texte intégralRésumé :
To improve the sensitivity of the steady combined forward and backward extrusion test proposed in previous work, an optimization job based on the finite element simulations was carried out. A raw material of 0.45% carbon steel was tested under different stain rates from 0.001s-1 to 1s-1 and different temperatures from 30°C to 400°C, and the material flow stresses were modelled by Hensel-Spittel equation. The deformation degree of the forward extrusion was set as 50%. The key parameters including the deformation degree of the backward extrusion, the ratio between the radius of the punch nose and the radius of the punch, the taper angle of the punch, the die angle, the sizing lands of the punch and the die were optimized. The sensitivity of the optimal design is improved about 20% compared with previous design when the friction factor is assumed as 0.03~0.15. The new group of calibration curves presents more scatter than the old group. The sensitivity improvement is also validated by the experimental works.
21
Bisri, Muhammad, Lily Montarcih Limantara et Dian Sisinggih. « Automatic calibration and sensitivity analysis of DISPRIN model parameters : A case study on Lesti watershed in East Java, Indonesia ». Journal of Water and Land Development 37, no 1 (1 juin 2018) : 141–52. http://dx.doi.org/10.2478/jwld-2018-0033.
Texte intégralRésumé :
AbstractThe Dee Investigation Simulation Program for Regulating Network (DISPRIN) model consists of eight tanks that are mutually interconnected. It contains 25 parameters involved in the process of transforming rainfall into runoff data. This complexity factor is the appeal to be explored in order to more efficiently. Parameterization process in this research is done by using Differential Evolution (DE) algorithm while parameters sensitivity analysis is done by using Monte Carlo simulation method. Software application models of merging the two concepts are called DISPRIN25-DE model and compiled using code program M-FILE from MATLAB. Results of research on Lesti watershed at the control point Tawangrejeni automatic water level recorder (AWLR) station (319.14 km2) in East Java Indonesia indicate that the model can work effectively for transforming rainfall into runoff data series. Model performance at the calibration stage provide value of NSE = 0.871 and PME = 0.343 while in the validation stage provide value of NSE = 0.823 and PME = 0.180. Good performance in the calibration process indicates that DE algorithm is able to solve problems of global optimization of the equations system with a large number of variables. The results of the sensitivity analysis of 25 parameters showed that 3 parameters have a strong sensitivity level, 7 parameters with a medium level and 15 other parameters showed weak sensitivity level to performance of DISPRIN model.
22
Graf, Gregor, Niki Nouri, Stefan Dietrich, Frederik Zanger et Volker Schulze. « Dual-Laser PBF-LB Processing of a High-Performance Maraging Tool Steel FeNiCoMoVTiAl ». Materials 14, no 15 (29 juillet 2021) : 4251. http://dx.doi.org/10.3390/ma14154251.
Texte intégralRésumé :
As part of an international research project (HiPTSLAM), the development and holistic processing of high-performance tool steels for AM is a promising topic regarding the acceptance of the laser powder bed fusion (PBF-LB) technology for functionally optimized die, forming and cutting tools. In a previous work, the newly developed maraging tool steel FeNiCoMoVTiAl was qualified to be processed by laser powder bed fusion (PBF-LB) with a material density of more than 99.9% using a suitable parameter set. To exploit further optimization potential, the influence of dual-laser processing strategies on the material structure and the resulting mechanical properties was investigated. After an initial calibration procedure, the build data were modified so that both lasers could be aligned to the same scanning track with a defined offset. A variation of the laser-based post-heating parameters enabled specific in-situ modifications of the thermal gradients compared to standard single-laser scanning strategies, leading to corresponding property changes in the produced material structure. An increase in microhardness of up to 15% was thus obtained from 411 HV up to 471 HV. The results of the investigation can be used to derive cross-material optimization potential to produce functionally graded high-performance components on PBF-LB systems with synchronized multi-laser technology.
23
Feuerhack, Andreas, Carolin Binotsch et Birgit Awiszus. « Formability of Hybrid Aluminum-Magnesium Compounds ». Key Engineering Materials 554-557 (juin 2013) : 21–28. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.21.
Texte intégralRésumé :
In the SFB 692 HALS (High-strength aluminum based lightweight materials for safety components), subproject B-3, the production of an aluminum magnesium compound by a hydrostatic co-extrusion process was investigated. The quality of these semi-finished products, especially the stability and robustness of the interface between the aluminum (AlMgSi1) sleeve and magnesium (AZ31) core, was of particular interest. Previous papers have described the first process optimization steps as the improvement of the die design as well as the numerical methods for identification of important process parameters and the development of a quality model for the interface. This paper describes the formability of such semi-finished products with subsequent forging processes, especially die forging. Therefore, two different die forging strategies were investigated. In the first approach the strand-shaped work piece, with a circular cross-section, was formed along its longitudinal axis with die forging. In the second approach the same geometry was radially formed with die forging. Thereby, the compound was formed in longitudinal direction up to an analytical equivalent strain value of 1.61 and in radial direction up to 1.38. First results showed that the interface of the aluminum magnesium compound is very stable and ductile enough to be forged. Dye penetration tests were performed to prove the stability of the interface in a first step. Then, micro sections were made to investigate the interface metallographically. No cracks or damages were detected with both test methods in the interface of the forged aluminum magnesium compound. Furthermore, numerical simulations were performed to analyze the forging processes in detail. Therefore, a full 3D simulation model was set-up with Forge2011 and the calibration was performed with the press force as well as the geometry aspects. The correlations between experiments and simulations are very well. By means of the calibrated simulation detailed analyses of interface section are performed and the stability of the interface was investigated. This shows that the compound quality reached by the hydrostatic co-extrusion process is very suitable for subsequent forming steps as die forging. The investigations show the potential of such hybrid compounds and clarify their application, especially in the automotive sector.
24
Kacor, Petr, Petr Bernat et Petr Moldrik. « Utilization of Two Sensors in Offline Diagnosis of Squirrel-Cage Rotors of Asynchronous Motors ». Energies 14, no 20 (13 octobre 2021) : 6573. http://dx.doi.org/10.3390/en14206573.
Texte intégralRésumé :
In the manufacture squirrel-cage rotors of asynchronous motors, a high standard of quality is required in every part of the production cycle. The die casting process usually creates porosity in the rotor bars. This most common defect in the rotor often remains hidden during the entire assembly of the machine and is usually only detected during final testing of the motor, i.e., at the end of the production process. This leads to unnecessary production costs. Therefore, the aim is to conduct a continuous control immediately after the rotor has been cast before further processing. In our paper, we are interested in selecting a suitable method of offline rotor diagnostics of an asynchronous motor that would be effective for these needs. In the first step, the selection of the method and its integration into the overall manufacturing process is carried out. The arrangement of the sensors and their calibration is then simulated on a 2D Finite Element Model of the rotor. The proposed offline measurement procedures and technologies are finally validated by testing measurements on a rotor that simulates the most frequently occurring faults. A test system is also developed that provides the operator continuous information about the running rotor measurements and makes it easier to evaluate the quality of the cast rotor by means of graphical visualization of the faults.
25
Schamel, Steven, et Milind D. Deo. « Role of Small-Scale Variations in Water Saturation in Optimization of Steamflood Heavy-Oil Recovery in the Midway-Sunset Field, California ». SPE Reservoir Evaluation & ; Engineering 9, no 02 (1 avril 2006) : 106–13. http://dx.doi.org/10.2118/83499-pa.
Texte intégralRésumé :
Summary In recovery of heavy oil by steamflood, efficiencies can be realized by limiting the placement of steam to the portions of the reservoir with highest oil saturations, thus reducing the disproportionate loss of heat to connate water. This optimization strategy requires knowledge of water-saturation (Sw) distributions within the heavy-oil reservoir at the scale of operations. Application of this strategy has contributed to the successful reactivation of the shut-in Pru Fee property in the Midway-Sunset field 1 mile west of Taft, a U.S. Dept. of Energy (DOE) Class 3 oil-technology demonstration project. The 40 new wells drilled and logged within the 40-acre Pru Fee property, together with a single continuous core, have permitted 3D mapping of Sw within the 250- to 350-ft-thick pay zone in the Monarch sand reservoir. Water saturations are observed to vary at three different scales:• A systematic vertical reduction in Sw through a 100- to 150-ft interval above the oil/water contact (OWC) caused by dominant capillary influence where the buoyancy effects are diminished by the low-density contrast of the 13°API oil and formation water.• Lateral variations in Sw on the scale of 10 to 100 ft caused principally by prior oil production from the reservoir, but modified by its internal stratigraphic architecture.• Bed-to-bed variations in Sw on the order of a few feet or less constrained by grain-size-controlled differences in porosity/permeability in these crudely graded sands. Overall production efficiency in the steamflood has been improved by limiting steam injection to the upper one-half to two-thirds of the pay zone, where Sw is lowest. Knowledge of the lateral variations in Sw has permitted more accurate appraisal of the effectiveness of individual producers and nine-spot injector/producer arrays. The recognition of the bed-to-bed variations has permitted a better petrophysical model for calibrating Sw calculated from logs. Introduction In recovery of heavy oil by steamflood, efficiencies can be realized by limiting the placement of steam to the portions of the reservoir with lowest water saturations (Sw), thus reducing the disproportionate loss of heat to connate water. The specific heat of heavy oil is less than half that of water, approximately 0.44 Btu lb-1F-1 (1.83 kJkg-1K-1) vs. 1.0 Btu lb-1F-1 (4.18 kJkg-1K-1), respectively (Burger et al. 1985). Effective execution of this optimization strategy requires knowledge of Sw distributions within the heavy-oil reservoir at the scale of operations. Application of this strategy has contributed to the successful reactivation of the shut-in Pru Fee property (Fig. 1) in the supergiant Midway-Sunset field 1 mile west of Taft, California, a DOE Class 3 oil-technology demonstration project. The Midway-Sunset field (Lennon 1990; Gregory 1996a) lies along the upturned western margin of the southern San Joaquin basin. Here, uppermost Miocene basin-center sands encased in organic-rich diatomite of the Monterey formation are close to the surface overlain unconformably by a thin cover of Pliocene and Pleistocene fluvial-lacustrine mudstones and sands (Nilsen 1996). The upper Miocene sands were emplaced into the basin from the granitic Salina Block situated immediately west of the San Andreas strike/slip fault, probably through point-source fan delta systems (Ryder and Thomson 1989; Hall and Link 1990). In the Midway-Sunset field, the uppermost Miocene sand reservoirs are debris flows and proximal turbidites of considerable thickness but irregular lateral continuity (Webb 1978). Transpressional growth folds forming adjacent to the tectonically active San Andreas fault system guided the debris flows into the synclines on the basin flanks (Webb 1978), thus creating thickened sand-reservoir "sweet spots." The Pru Fee property is located immediately south of the Spellacy anticline (Gregory 1996a) in a probable paleosynclinal trough. Although true anticlinal traps are common through most of the southern San Joaquin basin (Nilsen 1996), the oil pools in the Midway-Sunset field generally are related to unconformity or combination traps (Gregory 1996a). These are controlled by nested unconformities on the east-dipping Temblor range, with the top seal being Pleistocene Tulare shales, Pliocene Etchegoin shales, or diatomite mudstone within the upper Monterey formation itself. The diatomite mudstone encasing the sand bodies serves as both the lateral seal and the source rock. The trap at the Pru Fee property is an unconformity at the base of Etchegoin shales.
26
Zhu, Ling, Yan Wang, Anuj Pal et Guoming George Zhu. « Adaptive Design of Experiments for Automotive Engine Applications using Concurrent Bayesian Optimization ». ASME Letters in Dynamic Systems and Control, 1 avril 2022, 1–8. http://dx.doi.org/10.1115/1.4054222.
Texte intégralRésumé :
Abstract Most practical automotive problems require the design of experiments (DoE) over a number of different operating conditions to deliver optimal calibration parameters. DoE is especially crucial for automotive engine calibration problems due to its increasing complexity and nonlinearity. As the complexity of the system increases, the DOE applications require a significant amount of expensive testing. However, only a limited number of testings are available and desired. The current work addresses this issue by presenting an adaptive DoE method based on Bayesian optimization to find optimal parameter settings with a significantly reduced number of physical testings (or function evaluations). To further improve optimization efficiency, this work presents a new approach: Concurrent Bayesian optimization, which searches for optimal DoE under multiple operating conditions simultaneously. The method utilizes a surrogate model and a novel concurrent evolutionary multiobjective optimization method: concurrent NSGA-II, to solve adaptive DoE in multiple operating conditions with a limited number of function evaluations. The experimental study is carried out on a gasoline engine calibration problem using a high fidelity GT-SUITETM engine model. The experimental results demonstrate the effectiveness of the algorithm by optimizing engine performance with a significantly reduced number of expensive testings to achieve accurate optimal solutions. The method simultaneously performs engine calibration at eight different operating conditions using only 500 - 600 testings, compared to the traditional approach, where each operating condition requires 300 - 500 testings independently to achieve optimal results.
27
Ferreira, Fábio M. G., Eduardo N. Lages, Silvana M. B. Afonso et Paulo R. M. Lyra. « Using Design of Experiments and Design Optimization to Determine Statically Equivalent Mooring System on Truncated Water Depth ». Journal of Offshore Mechanics and Arctic Engineering 139, no 4 (16 mai 2017). http://dx.doi.org/10.1115/1.4036376.
Texte intégralRésumé :
Several procedures have been proposed and developed to overcome the challenge in ultradeepwaters testing. A realistic alternative approach uses a hybrid passive methodology through equivalent truncated mooring systems. Often, the searching for equivalent systems involves using a trial-and-error. As an alternative, researches on the use of optimization techniques to establish truncated mooring system with the required properties have been attempted in recent years. In the literature, it is available only approaches considering nongradient-based algorithms. These algorithms usually involve several parameters which require appropriate tuning to provide good performance. Our approach involves optimization algorithms based on gradient. We use a calibration method to perform a static adjustment of design variables to optimally fit truncated mooring system to full-depth mooring system, which proved efficient. A further feature of this work is related to the study of the influence of design variables on the response, through a methodology based on design of experiments (DOE), avoiding the use of irrelevant variables. It should be emphasized that to the authors' knowledge this DOE methodology presented was not seen in other works in this field. We will show that the methodology proposed in this work makes easy to find an equivalent mooring system on truncated water depth. We will present and discuss two fictitious cases, one case based on the literature and another case based on a real scenario. The results show a good agreement between truncated mooring system and full-depth mooring system for the static adjustment.
28
Abdulra’uf, L. B., et A. Lawal. « Application of Multivariate Data Analysis to the Determination of Multiclass Pesticide Residues in Fruits and Vegetables using Headspace Solid-Phase Microextraction Gas Chromatography-Mass Spectrometry ». Journal of Chemical Society of Nigeria 45, no 6 (31 octobre 2020). http://dx.doi.org/10.46602/jcsn.v45i6.538.
Texte intégralRésumé :
Design of experiment (DOE) was employed to develop a headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME/GC-MS) method for multiresidue analysis. The significance of SPME parameters was determined using Placket-Burman (P-B) design. The main effect and the interaction effect of the significant factors were also determined followed by the optimization of the significant factors using central composite design (CCD). A Minitab® statistical software was used to generate both the 27-4 Placket-Burman and the central composite design matrix. The same statistical software was also employed in the determination of the optimum level of the significant parameters using surface response optimizer and desirability surface plot. The most significant factors are: extraction temperature (90%), extraction time (80%), the pH and stirring rate (50% and 60% respectively). The optimum parameters are: Temperature, 62 °C; time, 34 min; NaCl, 10%; stirring, 350rpm; pH, 6. The figures of merit of analytical methodologies was determined using an internal standard calibration method. The linearity of the developed method ranges from 1- 500 µg/kg and correlation coefficient (R2) greater than 0.99. The average recovery was found between 74 – 115% and relative standard deviation ranges from 1.1 – 14%. The developed method was used to analyze 14 multiclass pesticide residues in two fruit (pear and grape) and two vegetable (lettuce and broccoli) samples, and the method was found to be satisfactory with LOD between 0.17 – 7.34 µg/kg and LOQ ranges from 0.55 – 24.50 µg/kg. Keyword: Design of experiment (DOE), solid phase microextraction, response surface optimizer, pesticide residues, Central composite Design
29
Suresh, R., M. Swamivelmanickam et S. Sivakrishnan. « Box-Behnken Design Approach for Optimization of a Liquid Chromatographic Method for the Determination of Anti Leukemic Drugs in Bulk and Pharmaceutical Formulations ». Journal of Pharmaceutical Research International, 17 décembre 2020, 67–77. http://dx.doi.org/10.9734/jpri/2020/v32i3530980.
Texte intégralRésumé :
To develop and validate a RP-HPLC method for the determination of selected anti- leukemic drugs in bulk and pharmaceutical formulations using Design of experiments. Development of the chromatographic method is based on design of experiments (DOE) approach, utilizing two level full factorial design for screening and Box-Behnken experimental design for optimization. In order to identify the significant parameters for the optimization, by simultaneously registering the main, interaction and quadratic effects of three factors such as volume of methanol (X1), concentration of buffer(X2) and flow rate (X3) on the selected responses like capacity factor K1 of first eluted peak (Y1), resolution of critical peaks RS (1,2) (Y2) and amp; RS (2,3) (Y3) and retention time of last peak tR4 (Y4) as responses. Analytes were separated on a Onyx monolithic- C18 (100×4.6mm) with mobile phase comprising Potassium dihydrogen orthophosphate (0.01M), Methanol and Acetonitrile in ratio of (30:34.29:35.71), with flow rate of 0.723 mL/min and pH 3.5 adjusted with dilute orthophosphoric acid. Total chromatographic analysis time per samples was approximately 5 minutes with DST(IS), IMT, IBT and SFN eluting with retention times of 2.64, 3.05, 3.81 and 4.59 minutes respectively. Calibration curves were linear over selected range 0.997 for the all analytes. The method was sensitive with the LODs were 10.457, 13.07 and 26.169 ng/mL and LOQs were 31.68, 39.6 and 79.3ng/mL for IMT, IBT and SFN respectively. Inter and Intra-day precision data (in terms of %RSD) was fond to be less than ≥3 respectively, Recoveries ranged ≥102±2% for Imatinib- Gleevec, Ibrutinib- Imbruvica and Sorafenib- Nexavar. The obtained results corroborated the potential of the proposed method for determination of all the three anti-leukemic drugs for routine analysis for products of similar type and composition.
30
Mandpe, Shilpa R., Vishal R. Parate et Jitendra B. Naik. « Experimental design approach, screening and optimization of system variables, analytical method development of flurbiprofen in nanoparticles and stability-indicating methods for high-pressure liquid chromatography ». Future Journal of Pharmaceutical Sciences 8, no 1 (5 septembre 2022). http://dx.doi.org/10.1186/s43094-022-00426-4.
Texte intégralRésumé :
Abstract Background The development of chromatographic method and the validation of a sensitive, simple, efficient, and reversed-phase high-performance liquid chromatography (RP-HPLC) approach were adopted for the drug flurbiprofen (FBP) in nanoparticles formulation by using a design of experiment (DoE). The critical method variables (CMVs) were screened using a statistical two-level fractional factorial design (FFD) followed by optimization of the selected CMVs that influence the analytical responses (ARs) of the RP-HPLC process by using two-level full factorial design. Results Statistical models are used to investigate the effects of system factors including column temperature, flow rate, and methanol in orthophosphoric acid (OPA) on the dependent responses, retention time, peak area, tailing factor, and theoretical plates in HPLC. The ideal column temperature (25 °C), flow rate (1 ml/min), and mobile phase (methanol 85 percent v/v in 0.05 percent OPA in water) were selected independently from the response surface at three levels (1, + 1, and 0) for further validation at constant solvent pH 2.75. Optimized method in the RP-HPLC resulted a retention time of 4.75 min, a peak area of 3975.12, a tailing factor of 0.73, and a total of 9697.7 theoretical plates followed by validation in accordance with the current ICH recommendations Q2 (R1). Linearity, precision, accuracy, assay, limit of detection (LOD), limit of quantification (LOQ), and robustness were all included in validation. The calibration curve was linear (r2 = 0.9997, slope = 70.72) for the concentration of 10 to 50 µg/ml, with a limit of detection of 0.14 µg/ml. Furthermore, stability-indicating methods demonstrate that drug degradation is highest in the presence of basic circumstances (about 96.49%), followed by oxidation (about 76.41%), and acidic conditions (about 48.12%), whereas drug is stable in some extent under neutral, photo (sunlight), and dry heat conditions. Conclusions Effect of independent variables on dependent responses was screened and optimized by using statistical software design. A method for drug development could be successfully implemented for the estimation of drug in nanoparticles formulation as well as for the routine analysis in bulk and pharmaceutical formulations. The high recovery and low relative standard deviation support the suitability of proposed method that could be employed. Graphical Abstract
31
Murasingh, S., J. Kuttippurath, S. Sandeep Dash, S. Raj, R. Remesan, Madan K. Jha et P. Kumar. « Long-term trends and projections of hydrological fluxes under RCP climate change scenarios for a mountainous river catchment of northeast India ». Journal of Water and Climate Change, 8 mars 2022. http://dx.doi.org/10.2166/wcc.2022.424.
Texte intégralRésumé :
Abstract The estimate of changes in hydrological fluxes from a climate change perspective is inevitable for assessing the sustainability of watersheds and conserving water resources. Here, we quantify and assess the changes in different hydrological flux components for the Manu-Deo River Basin (MDRB) of northeast India using Soil and Water Assessment Tool (SWAT) simulations and multi-temporal data at various resolutions. Sequential Uncertainty Fitting (SUFI-2) optimization is used to calibrate and validate the simulations for the periods 1984–2006 and 2007–2016 and for the four future representative concentration pathway (RCP) scenarios. The model performed reasonably well for the calibration and validation of daily data, in accordance with the Nash–Sutcliffe efficiency and coefficient of determination (0.54/0.55 and 0.52/0.72, respectively). The analysis for the period 1985–2013 reveals a decreasing trend in streamflow, which indicates increasing trends of drought there. Furthermore, it shows an increasing trend in evapotranspiration (ET) and decreasing trend for baseflow (BF), suggesting an adverse impact on agricultural production during lean periods. In addition, the RCP 2.6 and 6.0 scenarios for the monsoon season in future time scales are expected to cause a reduction in different flow components, although RCP 8.5 shows increased water availability there. The sub-basin-scale quantification and multi-temporal analysis of water availability under the present and future climate scenarios, as presented here, can assist water managers in formulating a suitable operational policy to implement a better decision-making framework for river and waterbody management. This is particularly important for mountainous regions, where input data are sparse and modelling of hydrological fluxes is challenging.