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Three compounds containing phenoxy acetohydrazide and their crystal structures were compared for derivatives of 2-methyl-phenoxy)acetohydrazide,2-(4-Methoxyphenoxy)acetohydrazide, and 2-(4-Methylphenoxy)acetohydrazide. Structures 1 and 3 crystallised in the monoclinic crystal system with fedorov groups P2/n and P21/c, whereas Structure 2 did so in the orthorhombic crystal system with fedorov group P212121. With the use of single crystal X-ray diffraction data taken at room temperature and full-matrix least-squares refinement techniques, the crystal structures of all three molecules were determined. The Reliable Index of the aforementioned compounds was discovered to be 0.0377 and 0.030 for derivatives 1 and 2, and 0.067 for compound 3. [ABSTRACT FROM AUTHOR]

To format Due to well-known features such as brushless designs, low costs, and reliable performance, The uses for induction motors are numerous. In recent years, many different control systems for induction motors have been created, and direct torque control has risen to prominence because of its simple control architecture and rapid dynamic torque responses. On the other hand, the direct torque control approach still has several disadvantages over other control systems; the most significant is the excessive torque ripple fresh approach that has been devised with space vector modulation. There are two hysteresis comparators discovered in a standard DTC drive. The DTC algorithm uses instant data to calculate the gate signals for operating or initialization for inverter. This uses average values, whereas the inverter switching signals use switching signals (notified by Sa, Sb, and Sc) are computed by this technique. High torque ripple and fluctuating switching frequency plague DTC drives using hysteresis comparators. The space vector, dependent on the reference torque and flux, is the most typical solution to these difficulties. A comparison of DTC and SVM-DTC is made in this work. Matlab-Simulink simulations with various techniques and no hysteresis band were compared. The torque and current ripple performances of the two control systems are compared. [ABSTRACT FROM AUTHOR]

For excellent performance of torque control In AC drive system, the direct torque control approach is applied. There are two hysteresis comparators are found in a standard DTC drive. Variable switching frequency and ripple of high torque plague DTC drives that use hysteresis comparators. The space vector, which is dependent upon some other value of torque and flux, is some kind of typical solution to these difficulties. The DTC-SVM techniques have a fixed frequency of switching. The space vector modulation methods are widely used in the control system. The switching signals which are used in DTC SVM techniques is based on averaged data, whereas the inverter is calculated using a space vector modulation method. This is primary distinction of DTC and DTC-SVM control approaches. Now, an advanced DTC-SVM method will be built on a VSI-fed Induction Motor in this thesis. To compensate for flux and torque defects, space vector modulation is a method that calculates the needed voltage space vector. F-logic control is a linguistic-based control algorithm strategy without the use of a mathematical model, which seeks to account for human understanding of how to regulate a system. The speed error which is denoted by e and change of speed error are the input value for the F-Logic controller. The speed error is derived by comparing the reference and actual speeds. Other benefits of using F-logic in F-controllers include reduced phase current distortion, faster torque response, and increased drive efficiency. [ABSTRACT FROM AUTHOR]

In this paper, the nonlinear Rosenau-Hyman equation with time dependent variable coefficients is considered for inves-tigating its invariant properties, exact solutions and conservation laws. Using Lie classical method, we derive point symmetries admitted by the governing equation. Symmetry reductions are performed for each components of optimal set. Also nonclassical approach is employed to find some additional supplementary symmetries and corresponding symmetry reductions are performed. Later three kinds of exact solutions of considered equation are presented graphically for different parameters. In addition, local conservation laws are constructed for the considered equation by multiplier approach. [ABSTRACT FROM AUTHOR]

A topic that evokes a large base for assorted studies, across numerous countries is soil classification. Recently, the world recorded an exorbitant rise in human population, the denouement is a higher demand for food and shelter. Both these factors directly demand exceptional study in geo technology, if not, a more reliable and faster method to do so. Conventional strategies taken by farmers are insufficient to meet the skyrocketing demands, and as a result, they must impede soil cultivation. This leads to the requirement to remain cognizant of the optimum soil type for a certain crop to maximize agricultural production. Several laboratory and field methods for classifying soil exist, however, these have constraints namely time and labour sine qua non. A need for a software-based soil categorization modus operandi that will assist humankind from a range of engineers to farmers, in reducing the time deviation is sought. This paper discusses apropos software, that allows soil classification to be achieved more efficiently. The functioning includes image processing and Computer vision-based soil classification methodologies, embodying the customary image assessing algorithms based on parameters, namely texture, colour, and particle size. [ABSTRACT FROM AUTHOR]

The compound crystallizes in the orthorhombic crystal system with space group P212121 having unit cell parameters: a=10.840(13), b=10.896(6), c=18.903(6) Å and Z=4. The crystal structure was solved by direct method using single crystal X-ray diffraction data collected at room temperature and refined by full-matrix least-squares procedures to a final R- value of 0.062 for 1044 observed reflections. [ABSTRACT FROM AUTHOR]

In the present study, the γ-Fe2O3 nanoparticles were prepared by using Ferritin solution via drop casting followed by annealing at 500°C for one hour in muffle furnace. The X-Ray diffraction (XRD) and Ultra Violet-Visible (UV-VIS) spectroscopy were carried out for phase identification and optical characterization. The γ- Fe2O3 phase was confirmed from the XRD analysis and the average crystallite size varied from approximately 19 to 24 nm calculated using Scherrer's formula.. The UV-VIS spectroscopy study implies dual band system with direct allowed band transitions at two values 2.21 and 2.58 eV using Tauc's relation. We compared two analysis schemes where, in one, the extrapolation of slope is used to find the band gap and in another singularity at Eg = hν identifies the band gap. In some systems, where, the dispersion in particle size smear the band edge; it is often difficult to find change of slope which causes ambiguity in determination of band gap. On the contrary, singularity approach eliminates the ambiguity in the analysis. [ABSTRACT FROM AUTHOR]

The present study aims to fabricate a novel design of composite structure i.e. a multi-layered sandwich structure with corrugated cores with different levels of CNT nanoparticles reinforcement. This study also analyses and compares the fundamental natural frequencies by performing modal analysis under different boundary conditions using impact hammer testing. The values of natural frequencies will help us understand the influence of CNT reinforcement on the structure as well as the properties of this structural design. Depending on this, the structures can be further applied in the aerospace industry like aircraft floors and wings. This is as a result owing to its high strength-to-weight ratio and stiffness. [ABSTRACT FROM AUTHOR]

A synchrotron beamline requires a set of reference values for calibration of photon beam energy, which are generally obtained from the absorption edges of different materials. However, due to oxidation and other chemical effects, these values are often different from the values of a pristine material. This makes the task of energy calibration difficult. In the present study, we have used a W/B4C multilayer for wavelength calibration for Soft x-ray reflectivity beamline (BL-03) at Indus-2. The structural parameters of the multilayer were obtained from Grazing Incidence X-ray Reflectivity (GIXRR) measurements. For energy calibration of soft x-ray beam, the reflectivity data at three different wavelengths were collected and analyzed to find correct wavelength values. The values so obtained were linearly interpolated to generate a curve for photon beam energy for 400-1500eV energy range. [ABSTRACT FROM AUTHOR]

In this study, we consider the Rosenau Hyman (RH) equation with arbitrary constant coefficients to examine its classical as well as nonclassical symmetries. Further optimal system for Lie algebra and corresponding similarity reductions are presented. Moreover, conservation laws are derived for the understudying equation. [ABSTRACT FROM AUTHOR]

A molecular dynamics simulation of small PuO2 nanocrystals consisting of 105−174 ions at the temperature T = 1700 K was carried out. The structures of the vertices and the surface created during thermal disordering and subsequent relaxation of these nanocrystals were studied. The vertices formed by two adjacent plutonium cations, as well as truncated vertices of the regular octahedron that consisted of 4 plutonium cations lying in the same plane (100), were most frequently encountered. Sharp vertices of the regular octahedron ending in one cation usually corresponded to metastable states of the crystal lattice or to crystallites with an increased specific energy. According to the results, sequences of the “magic numbers” were proposed to specify the sizes of plutonium dioxide nanocrystals characterized by the most stable surface. [ABSTRACT FROM AUTHOR]

We have scrutinized structural and electronic properties of SiXC (X=4,5,6) nanowires having a variant shape of cross-section. Properties of studied nanowires were drastically changed in compare to bulk Si and C structure. The density of charge (DOS) revealed delocalized metallic bonding for studied NWs. Number of conduction channel is slightly increased with the nanowire become bigger. All the considered nanowires are behaved as a poor metallic or semi metallic rather than semiconductor and insulator in bulk Si and C respectively. [ABSTRACT FROM AUTHOR]