Shape Memory Alloy Nanostructures With Coupled Dynamic Thermo-Mechanical Effects

Employing the Ginzburg-Landau phase-field theory, a new coupled dynamic thermo-mechanical 3D model has been proposed for modeling the cubic-to-tetragonal martensitic transformations in shape memory alloy (SMA) nanostructures. The stress-induced phase transformations and thermo-mechanical behavior of nanostructured SMAs have been investigated. The mechanical and thermal hysteresis phenomena, local non-uniform phase transformations and corresponding non-uniform temperature and deformations distributions are captured successfully using the developed model. The predicted microstructure evolution qualitatively matches with the experimental observations. The developed coupled dynamic model has provided a better understanding of underlying martensitic transformation mechanisms in SMAs, as well as their effect on the thermo-mechanical behavior of nanostructures.Comment: 8 pages, 3 figure

Fine needle cytology of Kaposi’s sarcoma in heterosexual male

Kaposi’s sarcomas the most common malignancy associated with Human Herpesvirus-8 (HHV8) infection. Though name is sarcoma but it is low grade vascular neoplasm. It is the tumour which arises from endothelial lining of vessels as well as lymphatic channels. So it involved all sites such as skin, Gastro intestine, lungs along with lymph nodes. We are presenting one such case of 65 year immunocompromised Indian male presented with multiple non blanching reddish bluish nodules on all extremities, chest, back with submandibular and cervical lymphadenopathy. Fine needle aspiration cytology (FNAC) was performed and diagnosis was given low grade spindle cell neoplasm consistent with Kaposi’s sarcoma which was confirmed on histopathology as Kaposi’s sarcoma

Numerical analysis of complex systems evolution with phase transformations at different spatial scales

This paper shows the existence of a critical dimension for finite length nanowires exhibiting shape memory effects. We give a brief survey of phase transformations, their classifications, and provide the basis of mathematical models for the phenomena involving such transformations, focusing on shape memory effects at the nanoscale. Main results are given for the dynamic of square-to-rectangular transformations modelled on the basis of the modified Ginzburg-Landau theory. The results were obtained by solving a fully coupled system of partial differential equations, accounting for the thermal field, a feature typically neglected in recent publications on the subject when microstructures of nanowires were modelled with phase-field approximations. Representative examples are shown for nanowires of length 2000nm and widths ranging from 200nm to 50nm. The observed microstructure patterns are different from the bulk situation due to the fact that interfacial energy becomes comparable at the nanoscale with the bulk energy

Real Time Face Detection and Recognition: Overview and Suggested Approach

This paper presents the detailed analysis of the existing state-of-the-art real time face detection and recognition approaches and a possible solution to the identified problems. The analysis covers the face detection, pattern recognition and measurement of facial part. The analysis of the Viola-Jones is followed by a possible model approach. This approach is based on a combination of techniques and algorithms working on Viola–Jones object detection platform

Effect of Aspect Ratio and Boundary Conditions in Modeling Shape Memory Alloy Nanostructures with 3D Coupled Dynamic Phase-Field Theories

The behavior of shape memory alloy (SMA) nanostructures is influenced by strain rate and temperature evolution during dynamic loading. The coupling between temperature, strain, and strain rate is essential to capture inherent thermomechanical behavior in SMAs. In this paper, we propose a new 3D phase-field model that accounts for two-way coupling between mechanical and thermal physics. We use the strain-based Ginzburg-Landau potential for cubic-to-tetragonal phase transformations. The variational formulation of the developed model is implemented in the isogeometric analysis framework to overcome numerical challenges. We have observed a complete disappearance of the out-of-plane martensitic variant in a very high aspect ratio SMA domain as well as the presence of three variants in equal portions in a low aspect ratio SMA domain. The dependence of different boundary conditions on the microstructure morphology has been examined energetically. The tensile tests on rectangular prism nanowires, using the displacement based loading, demonstrate the shape memory effect and pseudoelastic behavior. We have also observed that higher strain rates, as well as the lower aspect ratio domains, resulting in high yield stress and phase transformations occur at higher stress during dynamic axial loading

ASSESSING THE IMPACT OF CANAL NETWORK ON SURFACE WATERLOGGING USING REMOTE SENSING DATASETS IN ROHTAK DISTRICT, HARYANA

Remote Sensing is a very reliable and expeditious technique for assessment and mapping of surface waterlogged areas. In this study band ratio based NDWI index (Normalized Difference Water Index) was used for extracting water pixels from optical imageries. To overcome the limitation of false positives and cloud penetration associated with optical imageries waterlogged areas was also extracted using SAR (Synthetic Aperture Radar) images. Thresholding of NDWI for optical image and Sigma0 for SAR images was done using their respective histograms to distinguish water and terrestrial features. The total surface waterlogged areas in the district was calculated by integrating the results from both optical and SAR images. It was found that surface waterlogged areas varies temporally from pre-monsoon to post-monsoon period in Rohtak district, Haryana. The surface waterlogged area for pre monsoon period is around 9.7 km2 and for post monsoon period is 17.86 km2. The canal and surface drain network in the district was digitized using the high resolution Sentinel 2 MSS images. Since most of the canals in the area are unlined a buffer of 500 m either side of the canals and surface drains was considered to assess the impact of seepage and leakage from canals and surface drains. It was found that more than 50% of the total surface waterlogged areas fall within this buffer, clearly indicating the contribution of leakages from canals and surface drains on surface waterlogging

TRAINING, EDUCATION, RESEARCH AND CAPACITY BUILDING NEEDS AND FUTURE REQUIREMENTS IN APPLICATIONS OF GEOSPATIAL TECHNOLOGY FOR WATER RESOURCES MANAGEMENT

In India, water resources are managed at different levels, i.e. at central level by Ministry of Water Resources, River Development & Ganga Rejuvenation, Central Water Commission and Central Ground Water Board, at states level by state water resources departments, and at local level by Municipal Corporation and Panchayati Raj Institutions (PRIs). As per India’s national water policy of year 2012 focuses on adaption to climate change, enhancement of water availability, water demand management by efficient water use practices, management of floods and droughts, water supply and sanitation, trans-boundary rivers, conservation of water bodies and infrastructure, and finally research and training needs for each theme. Geospatial technology has unique role in all aforementioned themes. Therefore, research and training in use of Geospatial Technology (GST) in water sector is needed for each theme at different levels of water administration and water utilisation. The current paper discusses the existing framework and content of capacity building in water sector and geospatial technology in use at various government organizations and institutes. The major gap areas and future capacity building requirements are also highlighted, along with duration and timelines of training/capacity building programs. The use of distance learning/educations tools, social media, and e-learning are also highlighted in promoting use of GST in water sector. The emerging technological trends such as, new remote sensing sensors for measuring water cycle components, ground sensors based field instruments, cloud based data integration and computational models, webGIS based water information portals and training needs of new technologies are also emphasised