Time filter

Source Type

Vadodara, India

Desai P.,Navrachana University | Kant T.,Indian Institute of Technology Bombay
International Journal of Pressure Vessels and Piping | Year: 2013

A simplified and accurate semi analytical - numerical model is presented here to investigate the behavior of cylinders of finite length subjected to partially distributed band load. A diaphragm supported laminated cylinder under symmetric load which is considered as a two dimensional (2D) plane strain problem of elasticity in (r, z) direction. The boundary conditions are satisfied exactly in axial direction (z) by taking an analytical expression in terms of Fourier series expansion. Fundamental (basic) dependent variables are chosen in the radial coordinate of the cylinder. First order simultaneous ordinary differential equations are obtained as mathematical model which are integrated through an effective numerical integration technique by first transforming the boundary value problem (BVP) into a set of initial value problems (IVPs). The proposed method is successful in handling the 2D and three dimensional (3D) elasticity problems involving wide range of loadings, material properties and mixed variables. For cylinders subjected to band load, the convergence study is carried out and presented for different harmonics. The numerical results obtained are also first validated with existing literature for their accuracy. © 2013 Elsevier Ltd. Source

Desai P.,Navrachana University | Grace N.,Lawrence Technological University | Bebawy M.,Lawrence Technological University
Indian Concrete Journal | Year: 2012

This paper analyses a bridge model of spans 15.24 m (50') and 18.9 m (62') consisting of decked bulb T-beam girders subjected to transverse post tensioning. The numerical finite element model presented here determines the crack behaviour of the bridge using cohesive elements. A full depth high performance shear key is provided. The analysis considers AASHTO vehicle loadings as the static loading and includes temperature loadings. It was found that the bond between the shear key and bridge girder plays a major role in developing the longitudinal surface cracks on the bridges. It was also found that the transverse post tensioning and diaphragm spacing also affect the bridge stresses and displacements. ABAQUS finite element software was used to analyse the model. Data on bridge displacement is included in the results. Source

Singh M.P.,Navrachana University | Jain M.K.,Mohanlal Sukhadia University
2015 International Conference on Pervasive Computing: Advance Communication Technology and Application for Society, ICPC 2015 | Year: 2015

Instruction set architecture (ISA) of a processor fills the semantic gap between user and machine. A good ISA for a particular application should be able to address the issues of programmability, implementability, and compatibility. An application specific instruction set processor (ASIP) is a processor designed for a particular application. ISA customization is the process of integrating application specific ISEs (Instruction Set Extensions) into an ASIP's instruction set architecture. ISA customization pose a major challenge in realizing deigns for application specific processors. This paper is an attempt to investigate contemporary instruction set architectures and to identify issues in ISA customization for application specific instruction set processors. © 2015 IEEE. Source

Badgujar A.D.,Indian Institute of Technology Bombay | Badgujar A.D.,Navrachana University | Naik H.B.,Sardar Vallabhbhai National Institute of Technology, Surat | Atrey M.D.,Indian Institute of Technology Bombay
Physics Procedia | Year: 2015

Research on Stirling type Pulse Tube Cryocooler (PTC) is focused on achieving lower temperatures by cascading the stages or by multi-staging. Multi-staging can be done either by gas coupling or by thermal coupling of the stages. In the thermal coupling option, either a two stage cooler can pre-cool a single stage PTC to reach lower temperatures or a single stage PTC can cool a two stage PTC. In the present work, both these configurations are tested experimentally keeping the same two stage PTC. In case-1, the two stage PTC is used as a pre-cooling stage while in case-2, the single stage PTC is used as a pre-cooling stage. Length of the single stage is required and to be increased to match the two stages PTC for effective thermal coupling in case-1. The lowest temperature achieved in case-1 is 50.07 K where as in case-2 the lowest temperature achieved is 19.61 K at 17 bar charge pressure and 68 Hz frequency. The pressure drop in both the PTCs is compared to analyze the difference in performance. © 2015 The Authors. Source

Koppula P.,Navrachana University | Purohit N.,M. S. University of Baroda
Organic Communications | Year: 2013

With the aim of developing potential antimicrobial agents, a series of triazolo / tetrazolo isoquinolines incorporating both nitrogen and oxygen as part of the hetero aromatic ring were prepared from 4-alkyl-3-aroyl isocoumarins via a number of intermediate steps. Some novel coumarinoyl derivatives of isocoumarins were also synthesized starting from 4-alkyl-3-aroyl isocoumarin and characterized by FTIR, 1H NMR, Mass Spectroscopy and elemental analysis. All the title compounds 7a,b, 8a,b, 10a-g were evaluated for their antibacterial activity against S. Aureus (as gram positive), E. Coli (gram negative bacteria) and antifungal activity against Fusarium pallidoroseum & Chaetonium in vitro and analgesic activity which was tested in vivo on mice. Most of the compounds showed appreciable results for all the three activities. The relationship between the functional group variation and biological activity of the evaluated compound is discussed. The new compounds emerged as potential molecule for further development. © 2013 ACG Publications. Source

Discover hidden collaborations