Objects classification in still images using the region covariance descriptor

The goal of the Object Classification is to classify the objects in images. Classification aims for the recognition of generic classes, which is also known as Generic Object Recognition. This is quite different from Specific Object Recognition, such as recognizing specific person, own car, and etc. Human beings are generally better in recognizing generic classes than specific objects. Classification is a much harder problem to solve by artificial systems. Classification algorithm must be robust to changes in illumination, object scale, view point, and etc. The algorithm also has to manage large intra class variations and small inter class variations. In recent literature, some of the classification methods use Bag of Visual Words model. In this work the main emphasis is on region descriptor and representation of training images. Given a set of training images, interest points are detected through interest point detectors. Region around an interest point is described by a descriptor. Region covariance descriptor is adopted from porikli et al. [21], where they used this descriptor for object detection and classification. This region covariance descriptor is combined with Bag of Visual words model. We have used a different set of features for Classification task. Covariance of d-features, e.g. spatial location, Gaussian kernel with three different s values, first order Gaussian derivatives with two different s values, and second order Gaussian derivatives with four different s values, characterizes a region of interest. An image is also represented by Bag of Visual words obtained with both SIFT and Covariance descriptors. We worked on five datasets; Caltech-4, Caltech-3, Animal, Caltech-10, and Flower (17 classes), with first four taken from Caltech-256 and Caltech-101 datasets. Many researchers used Caltech-4 dataset for object classification task. The region covariance descriptor is outperforming SIFT descriptor on both Caltech-4 and Caltech-3 datasets, whereas Combined representation (SIFT + Covariance) is outperforming both SIFT and Covarianc

Electric-field-assisted growth of highly uniform and oriented gold nanotriangles on conducting glass substrates

A method for the growth of highly aligned gold nanotriangles (NTs) on conducting glass surfaces is described. This may be described as 'potential-assisted seed mediated growth'. Atomic force microscopy confirms that all the triangles observed are equilateral and are uniformly stacked. The NT-coated glass exhibits intense near-infrared absorption and strong surface-enhanced Raman activity

A fifteen atom silver cluster confined in bovine serum albumin

Luminescent Ag15 clusters confined in bovine serum albumin (BSA) have been prepared by a simple wet chemical route. The luminescence, exhibiting a maximum at 685 nm, is observable to the naked eye. The chemical composition of these clusters was analyzed using matrix assisted laser desorption ionization mass spectrometry (MALDI MS), X-ray photoelectron spectroscopy (XPS), and energy dispersive analysis of X-rays (EDAX). Intact Ag15@BSA is observed by MALDI MS. Multiple charge states of the cluster are observed confirming the mass assignment. The clusters showed a quantum yield of 10.71% in water and the luminescence was stable in a pH range of 1-12. Stability of the clusters was enhanced by the addition of polyvinylpyrrolidone (PVP). The clusters showed luminescence in the solid state as well. Evolution of clusters with variation in the amount of reducing agent added shows that the cluster formation goes through an intermediate state of bound silver, formed instantaneously after the addition of Ag+, which transforms to the cluster. High yield synthesis and exciting photophysical properties make our new material interesting for various applications such as biolabeling and imaging

Intra annual Variability of the Arabian Sea high salinity water mass in the South Eastern Arabian Sea during 2016 17

Intra-annual variability of the Arabian Sea high salinity water mass (ASHSW) in the South Eastern Arabian Sea (SEAS) and Gulf of Mannar (GoM) are addressed in this paper by utilisng the monthly missions carried out onboard INS Sagardhwani during 2016-17. Our observations revealed that the ASHSW was evident along the SEAS irrespective of seasons, whereas in the GoM the presence of ASHSW was observed during winter. The processes such as downwelling/up-welling, coastal currents, intrusion of low saline waters, stratification are clearly affects the spreading of the ASHSW. The characteristics such as core salinity value, depth and thickness of ASHSW exhibited remarkable spatio-temporal variability. Lateral mixing with the low saline waters in the region during winter reduces its core salinity. The intrusion of low saline waters was clearly seen upto 15 ON but the intrusion of low saline waters is not flowing through the GoM. The interface between the ASHSW and the prevailing low saline waters showed strong horizontal gradients of salinity. The presence of the ASHSW makes difference in the SLD and the below layer gradient which is sufficient to complicate or influence sound transmission. The spatio temporal variability of the ASHSW and its acoustic relevance are documented in this paper

Electric field enhancement and concomitant Raman spectral effects at the edges of a nanometre-thin gold mesotriangle

The local electric field enhancement at various regions of an individual nanometre-thin gold mesotriangle has been demonstrated both numerically and experimentally. This work provides, for the first time, direct experimental evidence of localized enhancement of Raman signals at three edges of nanometre-thin gold mesotriangles at single particle level, using Raman microscopy. Raman images were collected from mesotriangles of ~11 mm edge length and ~30 nm thickness, using adsorbed crystal violet as the probe molecule. Spatial distribution and the extent of electric field enhancement around a single mesotriangle are investigated theoretically by finite-difference time-domain (FDTD) simulations. Confocal Raman studies provided direct proof for the substantial electrical field enhancement at the edges and corners compared to the face of the mesotriangle. The simulated electric field enhancement was in the order, corner > edge > surface, which is in complete agreement with the experimental results

Metallocarbohedrenes: a new class of molecular clusters with cage structure

The chemistry of a new class of molecular clusters having closed cage structure, called metallocarbohedrenes or metcars, is described. These molecules of general formula M8C12, where M is a metal, were discovered in mass spectrometry experiments. By reacting laser-evaporated metal with hydrocarbons and cooling the reacton mixture in an inert atmosphere of helium, a number of metcar ions containing Ti, V, Hf, Zr, Mo, Cr and F e have been produced by different workers. The chemistry of these ions is gradually unfolding with several groups putting efforts in experimental and theoretical studies

Will “opt out” implementation save more lives; view of the South Asians’ in the UK

Organ transplantation is the gold standard treatment of choice for many patients with organ failure and has undoubtedly improved both the quality and longevity of life for the majority of patients. The success of human organ transplantation relies on the willingness of the public to donate their organs, either during their lifetime or after death. In the United Kingdom (UK), transplantation is limited by a shortage of donated organs, especially in the South Asian community. This leads to a disproportionate number of Asians waiting for transplants longer than the average waiting time, as often, most suitable matches are found between people of the same ethnic group. This disparity costs lives, and many who are waiting count down their days on the list and lead an agonizing life due to the scarcity of matching organ donors. This article is derived from a two phased study that sought to explore possible methods to increase the number of registered organ donors and cadaver organ retrieval in the South Asian community in the North West of England. A total of 907 participants completed the questionnaire and 10 semi structured interviews with individuals who declined to join the organ donor register were undertaken to understand the in-depth details of their negative attitude towards organ donation. This paper reflects on one of the focus areas of the study - the views of South Asians on the implementation of an opt-out system in the UK and to understand if the community will challenge or support such a donor recruitment method. This study was funded by the British Renal Society and supported by the Central Manchester Foundation Trust, University of Salford and National Health Service Blood and Transplant (NHSBT). Keywords: South Asian, Knowledge, Survey, Organ donation, Opt out, Opt in, Religio

Estimation of Compressional Wave Speed in Marine Sediments using Biot Stoll Model and Buckinghams Grain shearing Model

Acoustic properties of seafloor sediments can be estimated using theoretical models by giving geophysical properties of sediments as inputs to the respective models. Empirical relations connecting the geophysical and geoacoustic properties are available in literature. In this study an experimental assessment of two such theoretical models viz., Biot-Stoll model (BSM), a poro-elastic model and the Buckingham’s grain shearing (GS) model, a visco-elastic model is done by estimating the compressional wave speed. Compressional wave speed is measured using in-house developed sediment velocimeter and is compared with the speed estimated using both the models and a regression analysis was done. It was observed that the Coefficient of determination R2 for BSM and GS model are 0.769 and 0.729, respectively. It shows that once the constants used in GS model are evaluated for the Indian waters, then it can be used to estimate the acoustic properties of sediments

Generation of Groundwater Quality Index Map: A Case Study

Reliance on groundwater has been rapidly increasing, especially in the arid and semiarid regions, resulting in its overexploitation leading to deterioration of quality. Kurmapalli Vagu basin of Andhra Pradesh, a semi-critical region with respect to the stage of groundwater development is a good example. Its monitoring and assessment is imperative for devising preventive measures against health hazards. Groundwater samples from twenty five locations were collected and analyzed for various physico-chemical parameters in terms of Water Quality Index (WQI) to determine its suitability for drinking purposes. Seven locations were found to have WQI value within the limits. High values of WQI were mostly due to high content of Fluorides. WQI Contour map was generated to study spatial distribution of quality of groundwater. Suitable remedial measures and groundwater augmenting structures are proposed in the study area to improve the quality of groundwater. Keywords: Groundwater, WQI, Fluorosis, Groundwater augmenting structures