A Multi Hidden Recurrent Neural Network with a Modified Grey Wolf Optimizer

Identifying university students' weaknesses results in better learning and can function as an early warning system to enable students to improve. However, the satisfaction level of existing systems is not promising. New and dynamic hybrid systems are needed to imitate this mechanism. A hybrid system (a modified Recurrent Neural Network with an adapted Grey Wolf Optimizer) is used to forecast students' outcomes. This proposed system would improve instruction by the faculty and enhance the students' learning experiences. The results show that a modified recurrent neural network with an adapted Grey Wolf Optimizer has the best accuracy when compared with other models.Comment: 34 pages, published in PLoS ON

Bounds for the relative n-th nilpotency degree in compact groups

The line of investigation of the present paper goes back to a classical work of W. H. Gustafson of the 1973, in which it is described the probability that two randomly chosen group elements commute. In the same work, he gave some bounds for this kind of probability, providing information on the group structure. We have recently obtained some generalizations of his results for finite groups. Here we improve them in the context of the compact groups.Comment: 9 pages; to appear in Asian-European Journal of Mathematics with several improvement

Formal Analysis of Linear Control Systems using Theorem Proving

Control systems are an integral part of almost every engineering and physical system and thus their accurate analysis is of utmost importance. Traditionally, control systems are analyzed using paper-and-pencil proof and computer simulation methods, however, both of these methods cannot provide accurate analysis due to their inherent limitations. Model checking has been widely used to analyze control systems but the continuous nature of their environment and physical components cannot be truly captured by a state-transition system in this technique. To overcome these limitations, we propose to use higher-order-logic theorem proving for analyzing linear control systems based on a formalized theory of the Laplace transform method. For this purpose, we have formalized the foundations of linear control system analysis in higher-order logic so that a linear control system can be readily modeled and analyzed. The paper presents a new formalization of the Laplace transform and the formal verification of its properties that are frequently used in the transfer function based analysis to judge the frequency response, gain margin and phase margin, and stability of a linear control system. We also formalize the active realizations of various controllers, like Proportional-Integral-Derivative (PID), Proportional-Integral (PI), Proportional-Derivative (PD), and various active and passive compensators, like lead, lag and lag-lead. For illustration, we present a formal analysis of an unmanned free-swimming submersible vehicle using the HOL Light theorem prover.Comment: International Conference on Formal Engineering Method

Properties of Alumina-Magnesia Cutting Tools

The  high speed cutting tools that made from ceramic materials, alumina based, it is very important for the machining process. It has a hot hardness and abrasive resistance and chemical stability at the high temperature, but it has a brittleness and low fracture strength. In this study, synthesis samples from the α-alumina(Al2O3) doping with magnesia (MgO) with different percentage (0.35, 0.75, 1.1 % wt.)  and compare with the pure alumina properties. It is using cold uniaxial pressing (200 MPa) and sintered at (1500ᵒC) remain three hours for this samples. The purpose was to study the effect of the doping on the mechanical and physical properties and the ability to enhancing it. Numerical simulation was worked for the contact and friction between  the ceramic cutting tool and the workpiece material (AISI 1006 steel). This numerical methods dependent on ABAQUS Ver.6.14 program. The results show that ability of cutting and chip formation and successfully  propagation through this type of cutting tools without failure it at high speed (150-250)m/min. Also, the stress and heat generated due to ceramic cutting tool was presented The result appeared increasing in the hardness and the density value by the doping with MgO. By increase the percentage of magnesia that given enhanced the properties. The MgO as a second phase reduce alumina grain size and increase the hardness and the wear resistance to cutting tools. Small amount of magnesia enhanced the densification rate grain growth and accelerate the sintering rate. The magnesia doping enable to sinter the mixture alumina-magnesia to near theoretical density. The best result was found with 0.75% MgO at 1500oC (HV 19GPa). Keywords: ceramic, cutting tool, Johnson cook, Abaqus ,numerical. DOI: 10.7176/IEL/9-3-05 Publication date: April 30th 201

Age and growth analysis of the fish Mastacembelus armatus (Lacepede) from River Nayar, Garhwal Himalaya, Uttarakhand

The ability to age fish accurately is essential in understanding the dynamics of fish population. Age and growth determination in Mastacembelus armatus was assessed by the scale method which was verified by the length-frequency distribution method. The scales were small, elongated and the focus was shifted slightly uppish from the centre. The fish length and scale radius relationship was found linear (Scale radius = 6.974 + 0.452 Fish length; r = 0.9746) and authenticated the age analysis. Back calculation method was used to find out the size of fish at annulus formation, which confirmed four age rings in M. armatus  at the size of 14.07±0.92,  26.05±4.99,  37.96± 2.59  and  48.48±6.06 cm respectively. First two age rings were observed in the fish length group 30-40 cm, the third ring was observed in 40-50 cm and the fourth ring in 50-60 cm length group. The finding was dully validated by length-frequency distribution method. The growth annual increment (h) of M. armatus shows that the length increment was 14.07, 13.32, 11.91 and 10.52 cm during 1st, 2nd, 3rd and 4th year respectively. It shows that the fish grows continuously during its entire life period. The average growth (? h) was observed as 12.12 cm. annually. The assessment of age and growth rate of fish is a prerequisite to generate the information on recruitment, longevity and fluctuations in fishery caused by various year classes which is an important tool for rational exploitation of fish stock