Secure Key Management Based Mobile Authentication in Cloud

Authentication is important to the security of user data in a mobile cloud environment. Because of the server’s user credentials, it is subject to attacks. To maintain data authentication, a novel authentication mechanism is proposed. It consists of three independent phases: Registration, login, and authentication and key agreement. The user registers with the Registration Center (RC) by producing a secret number that isn’t stored in the phone, which protects against privileged insider attacks. The user and server generate a nonce for dynamic user identity and agree on a session secret key for safe communication. The passwords are not stored on the computer or provided in plain text, they are resistant to replay, guessing, and stolen verification attacks. The suggested protocol uses a one-way hash function and XOR operations, with the client having remote access to a large number of servers over a secure communication channel. Concentrates on HMAC and SHA3 for Collision Free Hashing and to overcome length extension attacks. HMACs are substantially less affected by collisions than their underlying hashing algorithms alone. So adding an HMAC to an MD5 or SHA hash would make it substantially more difficult to break via a rainbow table.     

Crystallography of solid–liquid interface and evolution of texture during directional solidification of Tb0.3Dy0.7Fe1.95 alloy

The effect of growth texture on the magnetostriction of ternary Tb_0.3Dy_0.7Fe_1.95 was studied by conducting unidirectional solidification experiments using a zoning set-up. Detailed texture evolutions were studied using X-ray diffraction on samples obtained by varying growth rates from 18 to 72 cm/h, under a temperature gradient of 100 °C/cm. The estimated texture co-efficient and pole figures of the samples indicate that during the onset of the solidification, <110> and <331>/‘rotated <110>’ texture components nucleate and grow in all the samples. However, as the solidification progresses, <112> texture component becomes dominant at higher growth rate. This results in an improvement of magnetostriction from 1000 to 1300 microstrains for samples grown at growth rates of 18 and 72 cm/h respectively. The transition of preferred growth direction occurs through intermediate orientations <123>. An attempt has been made in this paper to explain the occurrence of different growth texture by considering the stability of growing interface, its planar packing fraction and atomic stacking sequence of several low index planes.     

Blue Fluorescence and Bipolar Transport Materials Based on Anthracene and Their Application in OLEDs

The phenomenon of organic electroluminescence (EL) was first discovered from studies on anthracene crystals in the 1960s. Since then, its derivatives have been studied extensively in applications such as organic light-emitting diodes (OLEDs) and organic thin-film transistors because of their excellent EL, transport, and good electrochemical properties. A blue fluorescence emitter based on anthracene is also important in constructing hybrid tandem white OLEDs for lighting applications. This article provides a review about the development of blue host OLED materials based on molecules designed and derived from the core structure of anthracene and their application as bipolar charge-carrier transport materials in OLEDs. The recent development of efficient, stable, blue-doped p-i-n OLEDs with simplified device architecture based on the single common host 2-methyl-9,10-di(2-napthyl)anthracene, with its stable thin-film morphology, large band gap energy, high fluorescence quantum yield, and ambipolar charge-carrier transport properties, is also highlighted.     

Effect of thermomechanical processing on evolution of various phases in Ti-Nb alloys

This paper deals with the effect of thermomechanical processing on microstructural evolution of three alloys, viz. Ti-8Nb, Ti-12Nb and Ti-16Nb. The alloys were hot rolled at 800°C and then subjected to various heat treatments. Samples from hot-rolled alloys were given solution-treatment in β and α + β phase fields, respectively followed by water quenching and furnace cooling. The solution-treated alloys were subsequently aged at different temperatures for 24 h. Phases evolved after various heat treatments were studied using X-ray diffractometer, optical, scanning and transmission electron microscopes. The alloy Ti-8Nb exhibits α and β phases while the alloys Ti-12Nb and Ti-16Nb show the presence of α″, β and ω phases in the as-cast and hot-rolled conditions. The β solution treated and water quenched specimen of the alloy Ti-8Nb displays α″ phase while the alloys Ti-12Nb and Ti-16Nb exhibit α″, β and ω phases. The alloy Ti-8Nb shows the presence of α, β and ω phases while those of Ti-12Nb and Ti-16Nb display the presence of α, α″, β and ω in α + β solution treated and water quenched condition. The observation of ω phase in solution treated condition depends on the cooling rate and the Nb content while in the aged specimens, it is governed by aging temperature as well as the Nb content.     

Antifungal Activity of Some B,D-Seco Limonoids from Two Meliaceous Plants

Isolation and characterization of B,D-seco limonoids from Swietenia mahogani have been described. Seven limonoids from S. mahogani and five limonoids from Khaya senegalensis were tested for antifungal activity against the groundnut rust Puccinia arachidis. Mexicanolide, 3-acetoxy-mexicanolide, 3-hydroxymexicanolide, 2,3-dihydroxymexicanolide from K. senegalensis, and 6-acetylswietenine and 6-acetyl-3-tigloylswietenolide from S. mahogani effectively reduced the number of rust pustules on detached groundnut leaves. Possible correlation of structure to antifungal activity is discussed.     

Phase Transformation Textures in Hot-Rolled Binary Ti-Nb Alloys

The present work describes the phase transformation textures of three alloys, namely Ti-8Nb, Ti-12Nb, and Ti-16Nb after β and α + β solution treatments with different cooling rates. The strong, moderate, and weak variant selections have been observed depending on the alloy compositions and cooling rates. The β solution treated and water quenched (STWQ) specimens always exhibit a higher overall intensity than those of β solution treated and furnace cooled (STFC) specimens. This has been attributed to the presence of β phase, which has inhibited the growth of selected variants during cooling. The evidence of texture memory has also been observed after α → β→ α and α″ → β → α″ transformations. A combined effect of α _p, β, and ω phases has introduced different textures after α+β heat treatment than those of β heat-treated specimens. Extent of anisotropy in pole figures is more in water quenched (WQ) than those of furnace cooling (FC) specimens due to the development of equivalent orientations of individual crystallites during slow cooling.     

Rietveld refinement of the A3B (D019) and A2B (B82) phases in Ti–Sn and Ti–Ga alloys

The structures of A₃B (D0₁₉) and A₂B (B8₂) phases have been investigated using Rietveld refinement of XRD data. The analyzed chemistry of individual phases has been used to determine the site occupancy of initial models. The shifts in Ti atoms corresponding to 6(h) Wyckoff positions have been calculated in both the Ti₃Sn and Ti₃Ga phases. This is related to the presence of symmetry elements in D0₁₉ structure which in turn allows local shift due to different site occupancies resulting in different potentials. The nature of atomic shift is opposite in Ti₃Sn and Ti₃Ga phases. The site occupancy patterns of A₃B (Ti₃Sn, Ti₃Ga) and A₂B (Ti₂Sn and Ti₂Ga) are different due to unlike chemical compositions.     

Breast Calcifications and Histopathological Analysis on Tumour Detection by CNN

The most salient argument that needs to be addressed universally is Early Breast Cancer Detection (EBCD), which helps people live longer lives. The Computer-Aided Detection (CADs)/Computer-Aided Diagnosis (CADx) system is indeed a software automation tool developed to assist the health professions in Breast Cancer Detection and Diagnosis (BCDD) and minimise mortality by the use of medical histopathological image classification in much less time. This paper purposes of examining the accuracy of the Convolutional Neural Network (CNN), which can be used to perceive breast malignancies for initial breast cancer detection to determine which strategy is efficient for the early identification of breast cell malignancies formation of masses and Breast microcalcifications on the mammogram. When we have insufficient data for a new domain that is desired to be handled by a pre-trained Convolutional Neural Network of Residual Network (ResNet50) for Breast Cancer Detection and Diagnosis, to obtain the Discriminative Localization, Convolutional Neural Network with Class Activation Map (CAM) has also been used to perform breast microcalcifications detection to find a specific class in the Histopathological image. The test results indicate that this method performed almost 225.15% better at determining the exact location of disease (Discriminative Localization) through breast microcalcifications images. ResNet50 seems to have the highest level of accuracy for images of Benign Tumour (BT)/Malignant Tumour (MT) cases at 97.11%. ResNet50’s average accuracy for pre-trained Convolutional Neural Network is 94.17%.