Optimal Deep Hybrid Boltzmann Machine Based Arabic Corpus Classification Model

Natural Language Processing (NLP) for the Arabic language has gained much significance in recent years. The most commonly-utilized NLP task is the ‘Text Classification’ process. Its main intention is to apply the Machine Learning (ML) approaches for automatically classifying the textual files into one or more pre-defined categories. In ML approaches, the first and foremost crucial step is identifying an appropriate large dataset to test and train the method. One of the trending ML techniques, i.e., Deep Learning (DL) technique needs huge volumes of different types of datasets for training to yield the best outcomes. The current study designs a new Dice Optimization with a Deep Hybrid Boltzmann Machine-based Arabic Corpus Classification (DODHBM-ACC) model in this background. The presented DODHBM-ACC model primarily relies upon different stages of pre-processing and the word2vec word embedding process. For Arabic text classification, the DHBM technique is utilized. This technique is a hybrid version of the Deep Boltzmann Machine (DBM) and Deep Belief Network (DBN). It has the advantage of learning the decisive intention of the classification process. To adjust the hyperparameters of the DHBM technique, the Dice Optimization Algorithm (DOA) is exploited in this study. The experimental analysis was conducted to establish the superior performance of the proposed DODHBM-ACC model. The outcomes inferred the better performance of the proposed DODHBM-ACC model over other recent approaches.     

An efficient online secondary path estimation for feedback active noise control systems

In practical cases for active noise control (ANC), the secondary path has usually a time varying behavior. For these cases, an online secondary path modeling method that uses a white noise as a training signal is required to ensure convergence of the system. The modeling accuracy and the convergence rate are increased when a white noise with a larger variance is used. However, the larger variance increases the residual noise, which decreases performance of the system and additionally causes instability problem to feedback structures. A sudden change in the secondary path leads to divergence of the online secondary path modeling filter. To overcome these problems, this paper proposes a new approach for online secondary path modeling in feedback ANC systems. The proposed algorithm uses the advantages of white noise with larger variance to model the secondary path, but the injection is stopped at the optimum point to increase performance of the algorithm and to prevent the instability effect of the white noise. In this approach, instead of continuous injection of the white noise, a sudden change in secondary path during the operation makes the algorithm to reactivate injection of the white noise to correct the secondary path estimation. In addition, the proposed method models the secondary path without the need of using off-line estimation of the secondary path. Considering the above features increases the convergence rate and modeling accuracy, which results in a high system performance. Computer simulation results shown in this paper indicate effectiveness of the proposed method.     

Controlled Forging of a Nb Containing Microalloyed Steel for Automotive Applications

Controlled forging of microalloyed steels is a viable economical process for the manufacture of automotive parts. Ferrite grain refinement and precipitation hardening are the major microstructural parameters to enhance the mechanical properties of the forged components. In the current study, a modified thermomechanical treatment for additional ferrite grain refinement is developed by exploiting the effect of Nb in increasing the T _NR (no recrystallization temperature) and via phase transformation from a pancaked austenite. This is accomplished by performing the final passes of forging below the T _NR temperature followed by a controlled cooling stage to produce a mixture of fine grained ferrite, small scaled acicular ferrite as well as a limited amount of martensite. The effect of processing parameters in terms of forging strain, cooling rate and aging condition on the microstructure and mechanical properties of a medium carbon, Nb containing microalloyed steel is investigated. An attempt is made to identify a suitable microstructure that provides a proper combination of high strength and good impact toughness. The processing-microstructure relationships for the proposed novel forging procedure are discussed, and directions for further improvements are outlined.     

Bi-alphabetic pulse compression radar signal design

Ternary sequences have superior merit factors but they cannot be transmitted with existing technology. It is proposed that a ternary sequence be coded into a binary sequence for the purpose of transmission. On reception it can be processed as a binary sequence as received and also decoded into a ternary sequence. These two interpretations provide a coincidence detection scheme for efficient target detection provided that the corresponding signal design problem is solved. Such an algorithm is developed by taking the merit factor as desideratum and the Hamming scan as optimization technique. Merit factor values obtained in some cases are further improved by implementing a back-tracking algorithm for bi-alphabetic sequence.     

An investigation into the effect of Cs promotion on the catalytic activity of NiO in the direct decomposition of N2O

A series of Cs promoted NiO catalysts have been prepared and tested for direct decomposition of N₂O. These catalysts are characterized by BET surface area, X-ray diffraction (XRD), temperature programmed reduction (TPR), temperature programmed desorption of N₂O (TPD-N₂O) and X-ray photo electron spectroscopy (XPS). The Cs promoted NiO catalysts exhibit higher activity for the decomposition of N₂O compared to bulk NiO. The catalyst with Cs/Ni ratio of 0.1 showed highest activity. The enhancement in catalytic activity of the Cs promoted catalysts is attributed to the change in the electronic properties of NiO. The characterization techniques suggest weakening of Ni–O bond thereby the desorption of oxygen becomes more facile during the reaction. The Cs promoted NiO catalyst is effective at low reaction temperature and also in the presence of oxygen and steam in the feed stream. IICT Communication No: 070523.     

Influence of electric discharge machining on fatigue limit of high strength aluminum alloy under finish machining

Abstract

The aim of this study was to investigate the fatigue limit of the electric discharge machined aluminum alloy 2024 T6. Machining was performed at 3, 6, 9, and 12 A discharge current values while all other parameters were kept constant. The fatigue tests were performed on a four-point rotating bending machine at the frequency of 50 Hz and at ambient temperature. Fatigue limits at 10⁷ cycles were determined using staircase (up-and-down) method and the obtained data was analyzed statistically. For reference purposes, fatigue strength of the conventionally turned specimens was also found by the same technique. The EDM surface is characterized by its morphology, roughness, hardness, and thickness of the resolidified layer. The effects of discharge current values on these surface characterizing parameters and subsequent influence on fatigue limit have been discussed.     

Synthesis of oxygenated fatty acid esters from santalbic acid ester

The reaction of methyl octadec-trans-11-en-9-ynoate (1) with mercuric sulfate in the presence or absence of sulfuric acid is described. Treatment of 1 with mercuric sulfate in absolute methanol yielded methyl 9(10)-oxoocta-dec-trans-11-enoates (Product A). This product, upon treatment withm-chloroperbenzoic acid, afforded methyltrans-11,12-epoxy-9-oxooctadecanoate (4) and methyl 10-oxooctadec-trans-11-enoate (2). Sodium borohydride reduction of A furnished the corresponding hydroxy esters. The treatment of 1 with mercuric sulfate in the presence of sulfuric acid gave as major product methyl 9(10)-oxo-11(12)-methoxyoctadecanoates and methyl 9(10)-oxoocta-dec-trans-11-enoates as a minor product. When methyl 11,12-epoxyoctadec-9-ynoate was reacted with acid in methanol, methyl 12-hydroxy-11-methoxyoctadec-9-ynoate was formed, which on treatment with zinc chloride in CCl₄ yielded methyl 9,12-epoxyoctadec-9,11-dienoate exclusively. The preparation of oxo fatty esters from the total methyl esters ofSantalum album was also demonstrated. The structures of the products were established by chemical derivatization and spectral characterization.     

Effect of P/Fe ratio on the structure and ammoxidation functionality of Fe-P-O catalysts

Bulk FePO₄ catalysts, with varying P/Fe atomic ratio in the range of 1–1.6, were prepared and characterized by XRD, FT-IR, TPR, Potentiometric titration, Laser Raman, TEM, XPS and TG/DTA techniques in order to study the influence of P/Fe atomic ratio on the nature and extent of the active phase formation. The data obtained from XRD and Laser Raman techniques suggested predominant formation of the quartz type iron phosphate at close to stoichiometric P/Fe ratio, but as the ratio increased beyond 1.4 a progressive transformation of monomeric phosphate into its polymeric form was observed. XPS spectra reflected the presence of iron in its 3+ state when P/Fe ≤ 1.2 and exists as Fe²⁺ and Fe³⁺ when P/Fe ≥ 1.4. The catalytic properties of these iron phosphates were studied in the vapor phase ammoxidation, taking 2-methylpyrazine (MP) to 2-cyanopyrazine (CP) as an example. The ammoxidation activity of the catalysts was found to be proportional to the extent of quartz phase formed which in turn was proportional to the redox property, as observed by the oxidation functionality of the catalysts in benzyl alcohol transformation. However, the selectivity to nitrile was found to be dependent on the acid strength of the catalysts.     

Improvement in end-use quality of spring wheat varieties grown in different eras

Evaluation of wheat cultivars from different eras allows scientists to determine changes in agronomic and end-use quality characteristics associated with grain yield and end-use quality improvement over time. Forty-four spring wheat cultivars introduced or released since 1933 were evaluated for quality improvement using canonical variant analysis. It was observed that there was a considerable improvement in protein content from 1933 to 1964 whereas the genetic potential for straight grade flour protein from 11.34% in 1933–1964 to 12.13% in 1991–1996. Crude protein increased by 6.95% from 1933 to 1996. Ash content and flour yield declined by 9.55% and 5.51%, respectively. Total chapati scores of modern cultivars were 8.97% higher than those of cultivars grown earlier. The average spread ratio and overall cookie scores increased almost 5.53% and 4.44%, respectively from 1933 to 1996. It was also observed that overall cookie scores were highest during the period 1981–1990. The average dry gluten and total chapati scores of varieties grown since 1991 were approximately 10.20% and 74.72% respectively, which were 4.72% and 8.97% higher than those of cultivars grown since 1933. Average spread ratio and overall cookie scores increased almost 5.53% and 4.44% from 1933 to 1996, respectively. The era (1991–1996) containing the modern varieties showed a substantial improvement in lysine content than the era containing the oldest wheat varieties. Similarly amino acid score was also found to be 4.26% higher than the varieties released during the period 1933–1964.     

Hydroelectromagnetic phenomenain solutions

Macroscopic motion of weakly conducting liquids under the joint influence of hydrodynamic, electric, and magnetic fields is considered. Physical peculiarities and mechanisms of the occurring of hydroelectro-magnetic convection, as well as its applications, are discussed.