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1.
In this article, the problem of computing an optimal heat input in Luikov's heat and mass transfer problem is detailed and analyzed. The main objective is the establishment of an optimal time-dependent heat flux profile with the goal of maximizing the temperature and moisture sensitivities of some parameters to this excitation in a drying process. Such maximization makes the estimation of the desired parameters possible, easier, and with limited uncertainty intervals. It also helps to reduce the linearity dependence between the parameters of interest and the number of temperature and moisture sensors used. The estimation of the optimal heat input is obtained with Uzawa's algorithm, while the estimation of parameters is performed with Levenberg-Marquardt's method of minimization of the ordinary least-square criterion. The six dimensionless parameters characterizing Luikov's equations are estimated successfully with this optimal heat flux profile, which also helps to reduce the number of both temperature and moisture sensors needed in the estimation procedure. By doing so, the objective of estimating simultaneously the six parameters which appear in the formulation of Luikov's physical problem is reached by using a limited transient temperature and/or moisture measurements taken anywhere in the drying medium.  相似文献   
2.
A spectrally integrated clear-sky and three-layer cloudy-sky models were developed to determine atmospheric transmittances and instantaneous surface insolation. Half-hourly observations at 8 km spatial resolution in optical and thermal infrared bands from an Indian geostationary satellite (Kalpana-1) Very High Resolution Radiometer (VHRR) sensor were used to provide inputs to these models in addition to global 8 day aerosol optical depth and columnar ozone. Sensitivity analysis of the clear-sky model showed a higher influence of aerosol on global insolation, diffuse insolation, and its fraction as compared with water vapour and ozone. The root mean square error (RMSE) of insolation estimates of the daily integral was found to be 2.05 MJ m?2 (~11.2% of measured mean) with a high correlation coefficient (r?=?0.93) when compared with in situ measurements during 1 August 2008 to 31 March 2010 over six locations in India. The errors were found to reduce to 7.5% over 3 to 5 day averages. The comparison of annual estimates and equivalent reanalysis fields showed a mean difference of the order of ±1.7 MJ m?2 over the majority of the Indian landmass.  相似文献   
3.
A new approach to capacitance transient analysis, based on the matrix pencil (MP) method, is proposed for deep level transient spectroscopy (DLTS) (MP-DLTS). The MP method offers the least statistical variance of the estimates in the presence of noise. Simulation tests have shown this method to lead to a significant improvement in DLTS resolution even for low trap concentrations. Its noise sensitivity and resolution are quantified and compared with five different DLTS analysis techniques. The MP-DLTS method is found to outperform both DLTS spectrum and direct transient analysis techniques. An experimental investigation of the electrically active defects induced by a germanium preamorphization step prior to dopant implantation was undertaken using the MP-DLTS method. Two electron traps were detected in all samples and characterized  相似文献   
4.
To test the effects of the annual fluctuation of the environmental factors on the starch properties in potato tuber development, starches were isolated from potato cultivars grown for ten consecutive years (2001–2010) on the experimental farm in Memuro, Hokkaido, the northernmost island of Japan. The median granule size, phosphorus content, and rapid visco‐analyzer pasting properties, peak viscosity, breakdown, and pasting temperature of these starches were analyzed. Daily temperature and precipitation records in Memuro were obtained from the Japan Meteorological Agency. Moreover, the correlation coefficients of yearly accumulated temperature and precipitation from flowering to harvesting with all the starch quality parameters were calculated. No relationships of accumulated temperature with median granule size, peak viscosity, and breakdown were found. The low phosphorus content was slightly associated with the high accumulated temperature. The pasting temperature was significantly and positively correlated with the accumulated temperature, suggesting that the pasting temperature strongly responds to the environmental temperature during potato tuber development. In contrast, all the starch quality parameters were almost irrespective of the precipitation during potato tuber development.  相似文献   
5.
Wireless sensor network (WSN) based on IEEE 802.15.4 technology continues to gain considerable importance. The present work is based on this standard and a cluster tree network topology. This network is divided into many subgroups, each of which is characterized by its special IEEE parameters (beacon order [BO] and superframe order [SO]). A mathematical model for computing energy consumption was proposed to enable personal area network (PAN) coordinator to detect the current energy level in the battery. The proposed adaptive intervention is based on a comparison between the remaining energy and the diverse thresholds, which lead to an auto‐management of energy consumption. The proposed approach was evaluated using Inetmanet/Omnet++ simulator.  相似文献   
6.

The current study is set to investigate the problem of planning trajectories for a multi-robot system in a dynamic environment. The planning study is conducted in a “barrier-free” and “with obstacle” environment, based on the artificial potential field (APF) technique. This study seeks to improve the APF method in order to have good trajectory planning of a multi-robot system. Also, for multi-robot mobile systems, one of the main technical considerations is the technique used to coordinate the movements of different robots. In this paper, we proposed a centralized architecture for the trajectory planning of a multi-robot system.

  相似文献   
7.
Understanding the correlation between structural features of small‐molecule drugs and their mode of action is a fascinating topic and crucial for the drug‐discovery process. However, in many cases, knowledge of the exact parameters that dictate the mode of action is still lacking. Following a large screening for ubiquitin specific protease 2 (USP2) inhibition, an effective para‐quinone‐based inhibitor with an unclear mode of action was identified. To gain a deeper understanding of the mechanism of inhibition, a set of para‐quinones were prepared and studied for USP2 inhibition, electrocatalysis, and reactive oxygen species (ROS) quantification. The excellent correlation obtained from the above‐mentioned studies disclosed a distinct pattern of “N?C=O?N” in the bicyclic para‐quinones to be a crucial factor for ROS generation, and demonstrated that minor changes in such a skeleton drastically altered the ROS‐generating ability. The knowledge acquired herein would serve as an important guideline for future medicinal chemistry optimization of related structures to select the preferred mode of action.  相似文献   
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9.
In this paper, a fault recovery approach using dynamic reference modification and reconfigurable linear quadratic regulator is proposed. The idea is to modify the reference according to the system constraints, which become more strict after fault occurrence to avoid any actuator saturation and ensure system stability. The effectiveness of the proposed method is evaluated by a performance index based on tracking reference error and illustrated by an aircraft example subject to actuator faults and constrained on the actuator dynamic ranges. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
10.
This paper investigates the feed forward back propagation neural network (FFBPNN) and the support vector machine (SVM) for the classification of two Maghrebian dialects: Tunisian and Moroccan. The dialect used by the Moroccan speakers is called “La Darijja” and that of Tunisians is called “Darija”. An Automatic Speech Recognition System is implemented in order to identify ten Arabic digits (from zero to nine). The implementation of our present system consists of two phases: The features extraction using a variety of popular hybrid techniques and the classification phase using separately the FFBPNN and the SVM. The experimental results showed that the recognition rates with both approaches have reached 98.3 % with FFBPNN and 97.5 % with SVM.  相似文献   
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