With the increasing adoption of Web services, designing novel approaches for recommending relevant Web services has become of paramount importance especially to support many practical applications such as Web services composition. In this paper, a survey aiming at encompassing the state-of-the-art of interactive Web services composition recommendation approaches is presented. Both Web services composition and recommender systems concepts are introduced and their particular challenges are also discussed. Moreover, the need of using recommendation techniques to support Web services composition is also highlighted. The most relevant approaches dedicated to address this need are presented, categorized and compared.
Artificial neural networks aim to simulate the human nervous system using the interprocessing calculation methodology, but unfortunately cannot the preserve stimulus pattern. In this paper, we depend on the biological fact “information is coded within firing rate” and hence we propose an architecture for the preceptor in which the neurons' APs (Action Potentials) are transmitted in structures that represent the stimuli patterns, and the response of connected neuron through their synapses is highly proportional to the nature of these structures. The new preceptor that uses vector in space as input and the magic dyadic matrix shows a significant enhancement in many factors.
This paper demonstrates the basic information about the structure, the components, and the internal reactions of Nickel Metal Hydride (Ni-MH) batteries. Ni-MH batteries are leading in the market for being omnipresent in today's technology fields, powering everything from handsets to hybrid electric vehicles. A study on the chemical reactions inside Ni-MH batteries is to be represented briefly with highlighting on its specifications and mentioning some of the most important relevant applications of such batteries in today's industry. Moreover, the electric circuit model of Ni-MH batteries is to be discussed and taken into account in order to make sure that the reader will take note of all the needed primarily information about Ni-MH batteries.
This paper focuses on integrated comparative analysis of three kinds of classical states estimation algorithms from theory based on least squares method, including weighted least squares method, fast decoupled method, and the equivalent current measurement transformation method. The simulation experiment of IEEE14, 30 and 118 node system by MATLAB is carried out, then the efficiency analysis of three kinds of algorithms is done from the results of estimate, the number of iterations, the objective function and running time. Some conclusions are obtained. First, the weighted least squares method has the best estimation quality, good convergence rate, but the large amount of calculation, so it is not suitable for large-scale power system. Second, fast decoupled method has similar estimation quality. The weighted least squares method computes fast when the node system is small; the fast decoupled method has fast calculation speed when the node system is big. The process of fast decoupled method is relatively complex and applicable to high voltage system analysis. Third, the calculation speed of the equivalent current measurement transformation method is the fastest, but the estimation quality is the worst, and it is only suitable for the measurement system in which the measurement of the active power and reactive power is paired. Analysis and comparison of the results are helpful for selecting appropriate state estimation algorithm.
Heart failure comes in the top causes of death worldwide. The number of deaths from heart failure exceeds the number of deaths resulting from any other causes. Recent studies have focused on the use of machine learning techniques to develop predictive models that are able to predict the incidence of heart failure. The majority of these studies have used a binary output class, in which the prediction would be either the presence or absence of heart failure. In this study, a multi-level risk assessment of developing heart failure has been proposed, in which a five risk levels of heart failure can be predicted using C4.5 decision tree classifier. On the other hand, we are boosting the early prediction of heart failure through involving three main risk factors with the heart failure data set. Our predictive model shows an improvement on existing studies with 86.5% sensitivity, 95.5% specificity, and 86.53% accuracy.
In allusion to the defect that conventional weight least squares (WLS), when applied to the power system state estimation, generally takes the same weight. It causes large state estimation error. A state estimation method combining optimal weight setting with weighted least squares is proposed. On the basis of weighted least squares state estimation models, through the theoretical analysis of different kinds of voltage measurements, power injection measurements and power flow measurements data, which impact differently on the results, different weights are set corresponding to their measurement sensitivity in order to reduce the estimation errors. Finally, the algorithm is tested on IEEE14 bus system by MATLAB. Compared with the traditional weighted least squares, this method is similar with regard to iteration time. However, the voltage and phase angle state estimation accuracy can be improved by about 0.16 and 4.66 percentage points. Therefore, the algorithm has certain advantages and application value.
The evolution of battery management systems has imposed the necessity of evaluating batteries equivalent circuit models. The advantage of this type of modeling is to accurately estimate the dynamic aspects of a battery. Circuit parameters are identified for the purpose of forecasting different battery states. This paper presents multiple circuit models described in the literature. Four types of batteries are studied: Nickel-Metal Hybrid, Lithium-Ion, Lead-acid and Lithium Polymer.
Lithium-ion batteries have gained rapid popularity as an important means for the power sector. It is essential to model the battery in order to predict its behavior under various operating conditions to avoid any wrong operation and to safely manage to increase its life time. This paper introduces the most commonly used battery modelling techniques and their respective equivalent circuit models.
Fixed-width multipliers are widely used in digital signal processing (DSP) applications such as finite impulse response filter (FIR), fast Fourier transform (FFT) and discrete cosine transform (DCT). Baugh-Wooley multiplier is a preferred choice for the realization of 2's complement multiplication operation used in these applications. This paper presents the hardware realization and performance evaluation of 8×8 fixed-width modified Baugh-Wooley multiplier using state-of-the-art 7 series field programmable gate arrays (FPGAs) such as Virtex-7, Artix-7 and Zynq-7000, available from Xilinx. Different optimization goals are applied to the multiplier design and the performance is evaluated for area, speed and power. Simulation is done to verify the functionality of the design.
Nowadays, feature of electrical power becomes a main subject that takes concern of utilities and its customers. Due to undesired disturbances in power quality (PQ) field, many studies took place to analyze and detect the causes of power quality disturbances (PQD). This paper presents a testing of generated PQD on BIOPAC electrocardiogram (ECG). The generated disturbed signals are based on LabView software. The LabView can generate five categories of PQD in addition to the undisturbed signal. These categories are sags, swells, harmonics, and combination of sags and swells with harmonics. Each category can be easily controlled by a knob and different controls on the VI windows of the LabView software. In order to test these signals on the ECG, hardware was implemented. This hardware is based on NI myRIO 1900, Audio Amplifier of 12 Vout, and 12V/220V RMS AC step-up transformer.
In respect to the main goal of our ongoing work for maximizing the efficiency of wireless power transfer (WPT) systems, we focus in this paper on the results obtained from experiments conducted on a simulated WPT system after varying several design parameters. The selected parameters are classified into electrical design parameters related to the electrical circuit of the WPT system and the geometrical design parameters related directly to the coils used to transmit/receive the electric power. The model is simulated using Ansys/Maxwell 3-D software package. The results of this study have shown that the efficiency can be significantly improved by optimizing some simple, yet relevant, geometrical design parameters such as the size of the coils and/or by installing repeater coils between the transmitter and receiver.
