Stroboscopic holographic interferometry of vibration with space-variant phase

A method employing pulsed illumination for the holographic analysis of vibration with space-variant phase is described. Superimposition of two stroboscopically recorded interference patterns to get the amplitude and the phase of vibration at the intersections of fringes is suggested. Contour maps of these two quantities over the entire object surface can then be prepared by interpolation. Detailed solutions are presented for single and double frequency vibrations.     

Low power test architecture for dynamic read destructive fault detection in SRAM

Dynamic Read Destructive Fault (dRDF) is the outcome of resistive open defects in the core cells of static random-access memories (SRAMs). The sensitisation of dRDF involves either performing multiple read operations or creation of number of read equivalent stress (RES), on the core cell under test. Though the creation of RES is preferred over the performing multiple read operation on the core cell, cell dissipates more power during RES than during the read or write operation. This paper focuses on the reduction in power dissipation by optimisation of number of RESs, which are required to sensitise the dRDF during test mode of operation of SRAM. The novel pre-charge architecture has been proposed in order to reduce the power dissipation by limiting the number of RESs to an optimised number of two. The proposed low power architecture is simulated and analysed which shows reduction in power dissipation by reducing the number of RESs up to 18.18%.     

Finite versus small strain discrete dislocation analysis of cantilever bending of single crystals

Plastic size effects in single crystals are investi-gated by using finite strain and small strain discrete dislo-cation plasticity to analyse the response of cantilever beam specimens. Crystals with both one and two active slip sys-tems are analysed, as well as specimens with different beam aspect ratios. Over the range of specimen sizes analysed here, the bending stress versus applied tip displacement response has a strong hardening plastic component. This hardening rate increases with decreasing specimen size. The hardening rates are slightly lower when the finite strain discrete disloca-tion plasticity (DDP) formulation is employed as curving of the slip planes is accounted for in the finite strain formulation. This relaxes the back-stresses in the dislocation pile-ups and thereby reduces the hardening rate. Our calculations show that in line with the pure bending case, the bending stress in cantilever bending displays a plastic size dependence. How-ever, unlike pure bending, the bending flow strength of the larger aspect ratio cantilever beams is appreciably smaller. This is attributed to the fact that for the same applied bend-ing stress, longer beams have lower shear forces acting upon them and this results in a lower density of statistically stored dislocations.     

Theoretical optimization of metalp–n silicon Schottky barrier solar cell

The theoretical optimization of the design parametersN _A ,N _D andW _P has been done for efficient operation of Au-p-n Si solar cell including thermionic field emission, dependence of lifetime and mobility on impurity concentrations, dependence of absorption coefficient on wavelength, variation of barrier height and hence the optimum thickness ofp region with illumination. The optimized design parametersN _D =5×10²⁰ m⁻³,N _A =3×10²⁴ m⁻³ andW _P =11.8 nm yield efficiencyη=17.1% (AM0) andη=19.6% (AM1). These are reduced to 14.9% and 17.1% respectively if the metal layer series resistance and transmittance with ZnS antireflection coating are included. A practical value ofW _P =97.0 nm gives an efficiency of 12.2% (AM1).     

Thermal degradation studies on some lanthanide—edta complexes containing hydrazinium cation

Lighter and heavier lanthanide(III) ions react with dihydrazinium salts of ethylenediaminetetraacetic acid (H4edta) in aqueous solution to yield hydrazinium lanthanide ethylenediaminetetraacetate hydrate, N₂H₅[Ln(edta)(H₂O)₃]·(H₂O)₅ where Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb and Dy. The numbers of water molecules present inside the coordination sphere have been confirmed by X-ray single crystal studies. The presence of five water molecules as lattice water is clearly shown by the mass loss from the TG analyses. Dehydration of a known amount (1 g) of each sample were carried out at constant temperature (100–110°C) for about 5 min further confirms the number of non-coordinated water molecules. The complexes after the removal of lattice water undergo multi-step decomposition to give respective metal oxide as the final product. The DTA shows endotherms for dehydration and exotherms for the decomposition of the anhydrous complexes. The formation of the metal oxides was confirmed by X-ray powder diffraction studies.     

A validated high-performance thin-layer chromatography method for the simultaneous quantification of 6-gingerol,guggulsterone E and guggulsterone Z in coded formulation AYUSH SG-5 prepared for rheumatoid arthritis

JPC – Journal of Planar Chromatography – Modern TLC - A new, simple, selective, sensitive, precise, and robust high-performance thin-layer chromatography (HPTLC) method for the...     

Vector bundles over normal varieties trivialized by finite morphisms

Let Y be a normal and projective variety over an algebraically closed field k and V a vector bundle over Y. We prove that if there exist a k-scheme X and a finite surjective morphism g : X → Y that trivializes V then V is essentially finite.     

Synthesis of maradolipid

The first synthesis of maradolipid, a unique dissymmetrically 6,6'-di-O-acylated trehalose glycolipid isolated from C. elegans, is accomplished in five steps starting from trehalose in 45% overall yield. The short synthesis relies on dissymmetrization of trehalose core via regioselective acylation of a 2,3,4,2',3',4'-hexa-O-TMS trehalose 6,6'-diol derivative as a key step.     

Automated oral cancer identification using histopathological images: a hybrid feature extraction paradigm

Oral cancer (OC) is the sixth most common cancer in the world. In India it is the most common malignant neoplasm. Histopathological images have widely been used in the differential diagnosis of normal, oral precancerous (oral sub-mucous fibrosis (OSF)) and cancer lesions. However, this technique is limited by subjective interpretations and less accurate diagnosis. The objective of this work is to improve the classification accuracy based on textural features in the development of a computer assisted screening of OSF. The approach introduced here is to grade the histopathological tissue sections into normal, OSF without Dysplasia (OSFWD) and OSF with Dysplasia (OSFD), which would help the oral onco-pathologists to screen the subjects rapidly. The biopsy sections are stained with H&E. The optical density of the pixels in the light microscopic images is recorded and represented as matrix quantized as integers from 0 to 255 for each fundamental color (Red, Green, Blue), resulting in a M×N×3 matrix of integers. Depending on either normal or OSF condition, the image has various granular structures which are self similar patterns at different scales termed "texture". We have extracted these textural changes using Higher Order Spectra (HOS), Local Binary Pattern (LBP), and Laws Texture Energy (LTE) from the histopathological images (normal, OSFWD and OSFD). These feature vectors were fed to five different classifiers: Decision Tree (DT), Sugeno Fuzzy, Gaussian Mixture Model (GMM), K-Nearest Neighbor (K-NN), Radial Basis Probabilistic Neural Network (RBPNN) to select the best classifier. Our results show that combination of texture and HOS features coupled with Fuzzy classifier resulted in 95.7% accuracy, sensitivity and specificity of 94.5% and 98.8% respectively. Finally, we have proposed a novel integrated index called Oral Malignancy Index (OMI) using the HOS, LBP, LTE features, to diagnose benign or malignant tissues using just one number. We hope that this OMI can help the clinicians in making a faster and more objective detection of benign/malignant oral lesions.