A general partial discretizationmethodology for interlaminar stress computation in composite laminates

A two-point boundary value problem (BVP) is formed in the present work governed by a set of first-order coupled ordinary differential equations (ODEs) in terms of displacements and the transverse stresses through the thickness of laminate (in domain -h/2 < z < h/2) by introducing partial discretization methodology only in the plan area of the three dimensional (3D) laminate. The primary dependent variables in the ODEs are those which occur naturally on a plane z=a constant. An effective numerical integration (NI) technique is utilized for tackling the two-point BVP in an efficient manner. Numerical studies on cross-ply and angle-ply composite plates are performed and presented, involving both validation and solution of new problems

Use of proton pump inhibitors in dialysis unit in tertiary care hospital: a pharmaco-epidemiological study

Background: Proton pump inhibitors (PPI) are generally thought to be safer drug with fewer adverse effects. Though this class of the drug is thought to be well tolerated, a detail study about actual use of these agents in nephrology department is still awaited in many parts of India. There had been case reports and case series which were reporting PPIs producing acute interstitial nephritis progressing to acute renal failure. The risk of PPI treatment in haemodialysis patients remains unexplored. The aim of the study was to evaluate a drug utilization of PPI in patient undergoing haemodialysis procedure.Methods: In this study every day visit to the dialysis units of the hospitals was carried out. After taking consent from the patients, the information from the case-report form was noted like; age, sex, diagnosis, laboratory reports and drug prescried. No personally identifiable information about patient or physician was collected. After this an interview of patients was taken.Results: In this study, out of 126 patients 76.6% were male and 23.4% were female. Out of these 126 patients 88.89% patients were on PPI. Nearly 54% were using PPI for more than six months. Nearly 29% patients were using PPI for more than 12 months.Conclusions: As many case-reports and studies are suggesting, there is co-relation of PPI and acute interstitial nephritis from this study we suggest that especially in nephrology unit patients’, more caution must be exercised while using PPI

A study of assessment of knowledge, attitude and practice of antibiotic stewardship among healthcare providers in a tertiary care hospital of Sangli

Background: Antimicrobials are routinely used for variety of clinical conditions but are also misused leading to drug resistance bacteria in clinical practice. Consultants can gain the knowledge about it and can also have the depth of problem faced, their prescribing behavior mainly depends on their attitude and understanding of condition. Our aim of this study is to evaluate the knowledge and beliefs about antibiotics prescribing among health care workers in a tertiary care hospital of Sangli. Methods: Our present study was conducted in the Bharati hospital, BV (DU) medical college and hospital, Sangli. Ethical clearance from the institutional ethics committee was obtained and it was, cross-sectional questionnaire-based study carried out in the form of a survey in which a pretested, semi-structured, validated questionnaire was provided to junior residents, senior residents and faculty of different specialties and responses were recorded. Questionnaire comprises of 9 in knowledge, 10 in attitude and 10 in practice section. Results: Out of all participants 84.5% believed that no need of antibiotics for running and blocked nose. Majority 89.6% were expressed that sample culture should be sent before starting antibiotics. 90.4% participants believed that education of patients will help. Only 76.8% strictly adhere to the antibiotic policy of our hospital. Conclusions: The present study on antibiotic usage gives useful information about the knowledge, attitudes and practices of prescribers and help plan suitable educational modifications that aim at improving the antimicrobial prescribing and minimizing the development of drug resistance in our developing country

Semi-analytical solutions for static analysis of piezoelectric laminates

Displacement and stress analysis of an all-round simply supported piezoelectric laminate has been carried out with a new model. Formulation part has been developed using elasticity approach and the methodology is free from any a-priory assumption in thickness direction. The mathematical model is a set of mixed first ordered ordinary differential equations (ODEs). Solution is obtained using numerical integration in through-thickness direction. Accuracy of the proposed model is assessed by comparing numerical results for single layer piezoelectric plate as well as for multi-layered laminates with exact solutions available in literature and are found to be in good agreement with the same. Additional investigation has been performed to establish a few future references. (C) 2016 Elsevier Ltd. All rights reserved

Stress analyses of laminates under cylindrical bending

A semi-analytical approach for evaluation of stresses and displacements in composite and sandwich laminates Under cylindrical bending subjected to transverse load has been developed in this paper. Two dimensional (21)) partial differential equations (PDEs) of such a laminate are obtained by imposing plane-strain conditions of elasticity. The fundamental dependent variables are so selected in this formulation that they satisfy the continuity of displacements and transverse interlaminar stresses at the laminate interface through the thickness. The set of governing PDEs are transformed into a set Of Coupled first-order ordinary differential equations (ODEs) in thickness direction by assuming Suitable global orthogonal trigonometric functions for the fundamental variables satisfying the boundary conditions. These ODEs are numerically integrated by a specially formulated ODE integrator algorithm involving transformation of a two-point boundary value problem (BVP) into a set of initial value problems (IVPs). Numerical studies on both composite and sandwich laminates for various aspect ratios are performed and presented. Accuracy of the present approach is demonstrated by comparing the results with the available elasticity solution. It is seen that the present results are in excellent agreement with the elasticity solutions. Some new results for sandwich laminates and for uniform loading condition are presented for future reference. Copyright (c) 2006 , Ltd

2D semi-analytical solutions for single layer piezoelectric laminate subjected to electro-mechanical loading

Analysis of a piezoelectric laminate under plane strain condition of elasticity (cylindrical bending) has been performed with mixed semi-analytical model developed by Kant et al. (2007). The in-plane displacement, transverse displacement, transverse normal and shear stresses, electric potential and transverse electric displacement have been considered as fundamental dependent variables. The mathematical model consists of defining a two-point boundary value problem (BVP) governed by a set of coupled first order ordinary differential equations (ODEs). The accuracy and efficiency of the proposed model are assessed by comparing the numerical results from the present investigation with available elasticity solutions. (C) 2014 Elsevier Ltd. All rights reserved

Application of polymer composites in civil construction: a general review

Different applications of fiber reinforced polymer composites (FRPCs) for external strengthening in civil construction are reviewed in this paper. Experimental as well as analytical and numerical research contributions have been focussed in the review. The main structural components such as beams, columns and beam-column joints, have been reviewed and structural behavior of each component is discussed briefly. Finally, general concluding remarks are made along with possible future directions of research.© Elsevie

Nonlinear analysis of reinforced concrete beams strengthened with polymer composites

Strengthening of existing old structures has traditionally been accomplished by using conventional materials and techniques, viz., externally bonded steel plates, steel or concrete jackets, etc. Alternatively, fibre reinforced polymer composite (FRPC) products started being used to overcome problems associated with conventional materials in the mid 1950s because of their favourable engineering properties. Effectiveness of FRPC materials has been demonstrated through extensive experimental research throughout the world in the last two decades. However there is a need to use refined analytical tools to simulate response of strengthened system. In this paper, an attempt has been made to develop a numerical model of strengthened reinforced concrete (RC) beams with FRPC laminates. Material models for RC beams strengthened with FRPC laminates are described and verified through a nonlinear finite element (FE) commercial code, with the help of available experimental data. Three dimensional (3D) FE analysis has been performed by assuming perfect bonding between concrete and FRPC laminate. A parametric study has also been performed to examine effects of various parameters like fibre type, stirrup? spacing, etc. on the strengthening system. Through numerical simulation, it has been shown that it is possible to predict accurately the flexural response of RC beams strengthened with FRPC laminates by selecting an appropriate material constitutive model. Comparisons are made between the available experimental results in literature and FE analysis results obtained by the present investigators using load-deflection and load-strain plots as well as ultimate load of the strengthened beams. Furthermore, evaluation of crack patterns from FE analysis and experimental failure modes are discussed at the end