Methodology for predicting sequences of mean monthly clearness index and daily solar radiation data in remote areas: Application for sizing a stand-alone PV system

In this paper, a suitable adaptive neuro-fuzzy inference system (ANFIS) model is presented for estimating sequences of mean monthly clearness index () and total solar radiation data in isolated sites based on geographical coordinates. The magnitude of solar radiation is the most important parameter for sizing photovoltaic (PV) systems. The ANFIS model is trained by using a multi-layer perceptron (MLP) based on fuzzy logic (FL) rules. The inputs of the ANFIS are the latitude, longitude, and altitude, while the outputs are the 12-values of mean monthly clearness index . These data have been collected from 60 locations in Algeria. The results show that the performance of the proposed approach in the prediction of mean monthly clearness index is favorably compared to the measured values. The root mean square error (RMSE) between measured and estimated values varies between 0.0215 and 0.0235 and the mean absolute percentage error (MAPE) is less than 2.2%. In addition, a comparison between the results obtained by the ANFIS model and artificial neural network (ANN) models, is presented in order to show the advantage of the proposed method. An example for sizing a stand-alone PV system is also presented. This technique has been applied to Algerian locations, but it can be generalized for any geographical position. It can also be used for estimating other meteorological parameters such as temperature, humidity and wind speed.     

A New Coupled Solution for Interfacial Stresses Analysis in a Repaired Beam with an Adhesively Bonded Prestressed FRP Plate

This paper focuses on a new coupling solution for determining the elastic interfacial shear and normal stresses in an adhesive joint between a strengthening plate and a simply supported beam. The mismatch of the curvatures in the beam and plate is considered by including both the effect of the adherend shear deformations and the prestressed laminates model. This new method leads to the coupling of governing differential equations for the interfacial shear and normal stresses. Most of the other solutions in the literature assume that the beam and plate have an equal curvature to uncouple this effect. In this paper, however, a solution is presented to calculate the interfacial stresses of beams strengthened with a prestressed composite plate having a new rigidity model coupled with the shear lag effect, which are neglected by the previous studies. It is found that the present method can predict accurately stresses in the interior and near the ends of the adhesive layer, where the stress fields can be significantly influenced by the edge effects. A parametric study was carried out to show how the stress concentration and distribution are influenced by the dimensions of the adherends and the material properties of the strengthened beam.     

Detection of terahertz radiation with diode lasers

A standard commercial semiconductor is shown to be able to detect terahertz (THz) radiation at room temperature. A voltage variation across the active region of the device upon incident THz radiation is measured. The detected voltage signal scales linearly with the THz intensity measured with a Golay cell. A detailed analysis shows that thermal effects following the THz absorption by the carrier plasma play an important role in this detection process.     

Adaptive Generalized Predictive Control of Fractional Order Thermal Aluminum Rod

International Journal of Control, Automation and Systems - This paper presents the Adaptive Generalized Predictive Control (AGPC) of the heat conduction in a given aluminum rod modeled using...     

IRH-OF: A New Objective Function for RPL Routing Protocol in IoT Applications

Wireless Personal Communications - Faced to challenges of low power and lossy networks (LLN’s) as well as the nature of these networks without infrastructure, it remains the subject of...     

Neoadjuvant chemotherapy response evaluation in breast cancer based on mammogram registration and tumor segmentation

The standard approach for assessing the response of breast tumors to neoadjuvant chemotherapy is to monitor gross changes in tumor size as measured by physical exam and/or conventional imaging such as mammography. However, the deformable nature of the breast and variation in the imaging procedure, make it difficult to match the shape of breasts between serials of temporal mammograms, particularly when the tumor is shrinking due to the treatment. In this paper we propose a method for assessing residual tumor size following neoadjuvant chemotherapy by analyzing changes between pre-treatment and post-treatment mammograms. Our method consists of three steps: (1) pre-treatment and post-treatment mammograms were first registered in order to circumvent the problem of patient repositioning and breast deformation. (2) Tumors at corresponding locations were segmented using region growing segmentation, (3) and based on changes in tumor sizes the response rate is quantified. The proposed method has been tested on 6 breast cancer patients undergoing neoadjuvant chemotherapy, and the experimental results demonstrate that our approach may improve the ability of mammography to evaluate breast tumor response.     

CAD model simplification using a removing details and merging faces technique for a FEM simulation

The simulation process is currently used in the design and dimensioning of mechanical parts. With the progress of computer materials, the finite elements method (FEM) becomes the most used approach in the simulation of mechanical behaviour. The simulation process needs multiple Design-FEM loops. In order to accelerate those analysis loops, an adaptation of computer aided design (CAD) model is necessary. The adaptation step consists in the simplification of the CAD model geometry by eliminating details (holes, chamfers, fillet, etc.) and faces. In this paper, a novel technique of simplification of the CAD geometry is developed. This technique is a hybrid method based on a combination of the elimination details and merging faces. The merging of faces is based on the energetic method. With this approach, the computing time is reduced by the elimination of geometric details which do not boundary conditions. An implementation of the proposed algorithm on the Open Cascade platform is also presented. The results of the developed method are compared with a previous publication. The reduction of the computing time and the amelioration of the result precision highlight the efficiency of the presented method.     

A guided reactive GRASP for the capacitated multi-source Weber problem

The capacitated multi-source Weber problem entails finding both the locations of capacitated facilities on a plane and their customer allocations. A framework that uses adaptive learning and functional representation to construct the restricted candidate list (RCL) within a greedy randomized adaptive search procedure (GRASP) is put forward. An implementation of restricted regions that forbids new facilities to be located too close to the previously found facilities is also embedded into the search to build up the RCL more efficiently. The performance of this GRASP based approach is tested on three classes of instances with constant and variable capacities. Very competitive results are obtained when compared to the best known results from the literature.     

Spin-Wave Excitations in Evaporated Co/Pt Multilayers

The magnetic properties of evaporated Co/Pt multilayers have been studied by magnetic measurements and ferromagnetic resonance (FMR). The spin-wave resonances were observed in some multilayers in FMR experiments, which implied that spin waves were sustained by the whole and propagated through Pt layers. The relation of the resonance field H _res with the mode number n obeys the so-called n ² law and the interlayer coupling strength J _I has been determined. The temperature dependence of the spontaneous magnetization can be well described by Bloch’s law, in all multilayers. The increase of the spin-wave parameter B with decreasing cobalt thickness has been discussed. A spin-wave theory has been used to explain the temperature dependence of the magnetization and the approximate values for the bulk exchange interaction J _b and surface exchange interaction J _S for various Co/Pt multilayers have been obtained.     

Energy bands and spectral cues for Arabic vowels recognition

The present study examines the short and long Arabic vowels (/a/, /a:/, /i/, /i:/, /u/ and /u:/) with a new approach based on three methods: formant frequencies extraction, spectral moments and energy bands. Among Arabic language characteristics compared to other languages are long vowels which can be pronounced with different duration length. The formant frequencies are the most exploited in characterizing vowels in different languages nevertheless using only formants was not very significant for vowels identification especially when production duration augments. Therefore, our approach is to broaden previous studies and present new tools in order to characterize long vowels compared to short ones.