Adaptation of Open Source 2D DIC Software Ncorr for Solid Mechanics Applications

This study focuses on establishing the utility of open source, MATLAB based 2D Digital Image Correlation (DIC) software Ncorr for solid mechanics applications. Various experiments like ring under diametral compression and beam under four point loading are conducted and corresponding displacement and strain fields are estimated using Ncorr. These results are compared with commercially available 2D DIC software Vic 2D from correlated solutions. The results generated from Ncorr are found to be in good agreement with its commercial counterpart Vic 2D

The pattern of infections among under-fives: a call for actions

INTRODUCTION Infectious diseases are by far the most frustrating challenges in the health systems of most tropical nations. Unlike other challenges, infections have their causes known and solutions at hand. Paediatric world is the most important victim of infectious ailments. Various models, interventions for reduction/elimination of infectious diseases have been put forth but the strategies (in most tropical nations) have not bore the anticipated fruits. OBJECTIVES To assess the pattern of infections and its association with nutritional status among under-five years population of Dodoma in August – September 2007. METHODOLOGY A descriptive, cross-sectional community based study was done at Makulu ward of Dodoma district involving 396 under five year population derived from 322 different families. Data was collected using a standard structured questionnaire and analysed using epi-info 6 software. RESULTS Among 396 children studied, 52.3% were females. Maximum representation was found in the age range of 12-23 months (mode at age of 14.0 months). More than half (50.8%) of all children surveyed were found to have fever (at the time of the survey) and 58.8% were reported to have had fever within a period of 1 month prior to conduction of the study. Among children with fever, 52.3% had a normal weight to age ratio. More than 90% of surveyed children were reported to have been weaned before 6 months of age. CONCLUSION The prevalence of fever was found to be high (reflecting infectious nature) in this study. RECOMMENDATIONS More analytical studies are needed in this area to explain for the nature and causes of fever in this age group at Makulu ward

Implementation of MAD and Mean Absolute Deviation based Smoothing Algorithm for Displacement Data in Digital Image Correlation Technique

This study aims at obtaining smoothed strain fields from digital image correlation technique (DIC), by smoothing the displacement fields prior to strain computation. Both median absolute deviation (MAD) and mean absolute deviation based smoothing algorithms are implemented for data smoothing. On implementation of these algorithms, the noise levels in the strain fields are found to be reduced to a greater extent. For executing the whole field smoothing algorithm, an accurate boundary encoding algorithm is also developed

Study for Design of Magneto Rheological Damper

Semi-active isolation system have received attention over the active and passive isolation system for vibration, mitigation of vibration in industrial application is the essential development. Magneto rheological damper quick response to sudden maneuvers with less power consumption leads to many research and design of MR damper for different design parameters and variable current input, in this present work designed a MR damper with all the requisite design parameter information compiled from earlier work., number of coils required to generate the effective magnetic flux field has been calculated to design the magneto rheological damper and to arrive maximum magnetic flux density vs dc current with proper proportion percentage of ferrite particles in MR fluid which further leads to calculate shear stress and damper force can produce by the designed MR damper at variable current input

Material Characterization of Carbon Fiber Reinforced Polymer Laminate Using Virtual Fields Method

Material Characterization of Carbon Fiber Reinforced Polymer Laminate Using Virtual Fields Metho

Increases in salience of ethnic identity at work: the roles of ethnic assignation and ethnic identification

To better understand how ethnicity is actually experienced within organisations, we examined reported increases in ethnic identity salience at work and responses to such increases. Thirty British black Caribbean graduate employees were interviewed about how and when they experienced their ethnic identity at work. The findings demonstrated that increased salience in ethnic identity was experienced in two key ways: through ‘ethnic assignation’ (a ‘push’ towards ethnic identity) and ‘ethnic identification’ (a ‘pull’ towards ethnic identity). We explore how and when ethnic assignation and ethnic identification occur at work, and their relevance to how workplaces are experienced by this group of minority ethnic employees. The findings suggest the need for further research attention to the dynamic and episodic nature of social identity, including ethnic identity, within organisations, and to the impact of such increases in salience of social identities on behaviour at work

Effect of Interface Crack and Corner Singularity in Bimaterial System – Experimental and Numerical Investigation

It is of great importance to study behavior of adhesively bonded dissimilar materials as they are widely used in electronic packaging, plastic integrated circuit, welded joints of dissimilar materials, composite materials etc. Due to mechanical loading, cyclic variation in climate or changes in moisture content of ambience leads to high stress at corners or interface, where discontinuities of geometry or material property is present. In this study an attempt has been made to study the behavior of small crack at the interface of aluminum/epoxy bimaterial system. Initially stress intensity factors are estimated experimentally by digital photoelasticity and then compared numerically with a finite element model. Experimentally, ten-step phase shifting technique is used to get isochromatic phase map without ambiguity and later it is unwrapped to get the total fringe order over the model domain. Three fringe photoelasticity technique is also used to get total fringe order. From this information stress intensity factor at interface crack tip is determined using simplified multi-parameter stress field equation of Deng involving over-deterministic least square approach. Numerically stress intensity factors are evaluated by virtual crack closure integral method. Numerically J-integral method is also used for evaluating stress intensity factors for interface crack. We may have to account for the effect of material mismatch as well as temperatute effect at material interfaces. A bimaterial wedge corner can also act as a source for high stress concentration, and it’s singularity is different from crack tip. In the present work, analytically order of singularity is found out for the aluminium/epoxy bimaterial system and using this, stress fields around the corner is predicted. For finding the order of singularity modified stress field equations of Seweryn has been used with appropriate boundary conditions. A linear elastic fracture mechanics frame work is applied for the entire study

Experimental Study and Optimization of Machining Parameters in Turning of AISI 1040 Steel with Micro-grooved WC Cutting Tools

In dry turning, control over chip formation and the need for the automated machining lead to an advancement in cutting tools. Such concern towards chip breakability is necessary in reducing tool wear, tool tip temperatures and surface roughness of workpiece material. The present study proposes a new development in the traditionally available cutting tools, which acts like a chip breaker. A series of micro-grooves are machined on the rake face of Tungsten carbide (WC) cutting tools using sinker Electric Discharge Machine (EDM). These micro-grooved tools are used to dissolve long continuous chips and heat from the cutting zone in the dry machining of AISI 1040 steel. The results of micro-grooved cutting tools have shown improvement in reducing the tool tip temperatures and surface roughness compared to the conventional cutting tools. The consolidated chip flow phenomenon of plain WC tools is used to decide the location of micro-grooves on the tool rake face. A Taguchi orthogonal array is used to design an experimental layout with minimum number of repetitions in the experiments. Signal-to-noise  ratios and ANOVA is used to understand and identify the significant factors & their level among the input variables on responses.From the results, it is identified that the cutting speed is the most influencing parameter for tool tip temperature at level 1 (i.e. 112 m/min) and surface roughness at level 5 (i.e. 720 m/min)