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The purpose of this paper is to investigate the prominence of mechanical excitations at the time of welding. In the past years, the process of welding technology has expanded its influence in manufacturing. The crucial drawback of conventional welding is prompted by internal stresses and distortions, which is the focal reason for weld defects. These weld defects can be diminished by the process called post-weld heat treatment (PWHT), which consumes more working hours and needs skilled workers. To replace these PWHT processes, mechanical vibrations are introduced during the process of welding to diminish these weld defects.

In the current research, the mechanical vibrations are transferred to weld-pool through vibro-motor and DC motor connected to the electrode. As per standards, the tensile test specimens were prepared for welding with different voltages of vibro-motor and DC motor respectively. The weld joints were tested for tensile strength and analyzed the microstructure at the fusion zone.

Melt-ability at fusion zone of 1018 mild steel was investigated by the single-stroke intense heat process of fusion welding. It is observed that the mechanical vibrations technique has a profound influence on the enhancement of the fusion zone characteristics and grain structure. The peak value of the tensile strength is observed at 100 s of vibration, 190 V of vibro-motor voltage and 18 V of electrode voltage. The tensile strength of the welded joints with vibrations is increased up to 22.64% when it is compared with conventional welding. The enhancement of the tensile strength of the weld bead was obtained because of the formation of fine grain structure. So, mechanical vibrations are identified as the most convenient method for improving the mild steel alloys weld quality.

A novel approach called mechanical vibrations during the process of welding is implemented for fusion zone refinement.

The purpose of this study is to explore the importance of vibrations during welding process. In recent years, welding has gained its supremacy in the field of production. The main set back of the welding process is induced residual stresses, which is a major cause for many welding defects. These defects can be minimized by post-weld heat treatment methods, which is a time consuming and laborious process. In the recent past, a technique of exciting the weld-pool by vibrating the work-pieces was also adopted to minimize the above-mentioned stresses. A novel technique of electrode vibration is another effective way of transferring the vibrations to the weld-pool to influence the induced residual stress.

In this research, the electrode is vibrated with the help of an electric motor. The specimens were prepared as per American Society for Testing and Materials standards and welded with varying frequencies and voltages. The weldments are tested for hardness along the weld bead and heat affected zone, also the microstructure of the fusion zone is analyzed.

It is observed that there is an improvement in the hardness because of the grain refinement, which is a result of proper excitation of the weld-pool. It is observed that there is an improvement in hardness test up to 28.69% when compared with the conventional welding process. The peak value of hardness is observed at a frequency of 4,450 Hz. This is because of fine grain structure at this frequency, which is observed through the microstructure analysis.

A novel technique is introduced to refine the weld-pool through electrode vibrations. To improve the hardness of the welded joints, vibrations play a major role by refining the grain structure. The vibrations are imparted with the help of a special equipment attached to the electrode.

The present work aims at improving the performance of the engine using optimized fuel injection strategies and operating parameters for plastic oil ethanol blends. To optimize and predict the engine injection and operational parameters, response surface methodology (RSM) and artificial neural networks (ANN) are used respectively.

The engine operating parameters such as load, compression ratio, injection timing and the injection pressure are taken as inputs whereas brake thermal efficiency (BTHE), brake-specific fuel consumption (BSFC), carbon monoxide (CO), hydrocarbons (HC), oxides of nitrogen (NO_x) and smoke emissions are treated as outputs. The experiments are designed according to the design of experiments, and optimization is carried out to find the optimum operational and injection parameters for plastic oil ethanol blends in the engine.

Optimum operational parameters of the engine when fuelled with plastic oil and ethanol blends are obtained at 8 kg of load, injection pressure of 257 bar, injection timing of 17° before top dead center and blend of 15%. The engine performance parameters obtained at optimum engine running conditions are BTHE 32.5%, BSFC 0.24 kg/kW.h, CO 0.057%, HC 10 ppm, NO_x 324.13 ppm and smoke 79.1%. The values predicted from ANN are found to be more close to experimental values when compared with the values of RSM.

In the present work, a comparative analysis is carried out on the prediction capabilities of ANN and RSM for variable compression ratio engine fuelled with ethanol blends of plastic oil. The error of prediction for ANN is less than 5% for all the responses such as BTHE, BSFC, CO and NO_x except for HC emission which is 12.8%.

This paper aims to deal with the optimization of engine operational parameters such as load, compression ratio and blend percentage of fuel using a combined approach of particle swarm optimization (PSO) with Derringer’s desirability.

The performance parameters such as brake thermal efficiency (BTHE), brake specific fuel consumption (BSFC), CO, HC, NO_x and smoke are considered as objectives with compression ratio, blend percentage and load as input factors. Optimization is carried out by using PSO coupled with the desirability approach.

From results, the optimum operating conditions are found to be at compression ratio of 18.5 per cent of fuel blend and 11 kg of load. At this input’s parameters of the engine, outputs performance parameters are found to be 34.84 per cent of BTHE, 0.29 kg/kWh of BSFC, 2.86 per cent of CO, 13 ppm of HC, 490 ppm of NO_x and 26.25 per cent of smoke.

The present study explores the abilities of both particle swarm algorithm and desirability approach when used together. The combined approach resulted in faster convergence and better prediction capability. The present approach predicted performance characteristics of the variable compression ratio engine with less than 10 per cent error.

This paper aims to deal with heat transfer enhancement because of transverse vibration on counter flow concentric pipe heat exchanger. Experiments were performed at different vibrator positions with varying amplitudes and frequencies.

Tests are carried out at 4 different vibration frequencies (20, 40, 60 and 100 Hz), 3 vibration amplitudes (23, 46 and 69 mm) and at 3 vibrator positions (1/4, 1/2 and 3/4 of pipe length) with respect to hot water inlet under turbulent flow condition.

Experimental results indicate that Nusselt number is enhanced to a maximum extent of 44% with vibration when compared to Nusselt number without vibration at a frequency of 40 Hz, an amplitude of 69 mm and at a vibrator position of one-fourth of pipe length with respect to hot water inlet.

Empirical correlation is developed from experimental data to estimate the heat transfer coefficient with vibration for experimental frequency range with an error estimate of approximately ±10%.

The gas tungsten arc welding (GTAW) process is a widely used process that produces quality weldments. But the high heat generation from the GTAW arc can cause extreme temperatures as high as 20,000°C. The residual stresses and deformations are high accordingly. One of the methods for decreasing residual stresses and deformations is to change the welding pattern. In the literature, there are not so many examples of modeling dealing with welding patterns. This paper aims to investigate the influence of welding patterns on the deformations.

In this work, back-stepping patterns and partitioning of the weld line were investigated and the distortions and residual stresses were calculated. By doing this, temperature-dependent thermophysical and thermo-mechanical material properties were used. The temperature distribution and deformation from experiments with the same welding conditions were used for validation purposes.

Seven different welding patterns were analyzed. There is only one pattern with a single partition. There are three patterns investigated for both two and three partitioned weldings. The minimum deformation and the optimum residual stress combination is obtained for the last pattern, which is a three partitioned and diverging pattern.

The most important aspect of this paper is that it deals with welding patterns, which is not much studied beforehand. The other important thing is that the structural part and the thermal part of the simulation were coupled mutually and validated according to experiments.

Purpose – The intent of this chapter is to examine the lessons that BRAC, a Bangladesh-based NGO, learned over the course of implementing its para-professional teacher model in Afghanistan and Bangladesh, and their implications for UNESCO's Education for All (EFA) initiative.Methodology – The objectives of this chapter are achieved by the analysis of secondary sources such as reports and academic articles.Findings – We find that through a combination of strong oversight and management, BRAC's para-teacher model compensates for its comparatively less formally trained teachers. This may serve as a model for nations implementing EFA initiatives by allowing them to hire more para-teachers as a cost-saving measure.Research limitations – This study is mainly reliant on secondary sources, which highlights the limited information on the quality of BRAC's education efforts in Afghanistan.Practical implications – Through a combination of strong oversight and practical training, BRAC has seemingly developed a robust para-teacher model, one that may be implemented in other contexts, especially in countries that are members of the EFA initiative and face a shortage of qualified teachers who can help achieve Universal Primary Education (UPE).Social implications – In addition to being a cost-saving measure for education, hiring para-teachers from local communities has the additional benefit of providing employment for women in rural communities, which may have a positive impact on women's empowerment.Value – This chapter provides a unique look at innovations in teacher training by NGOs and their implications for the global contexts of the EFA initiative.

The study is prompted by the fact that most SMEs may not have the wherewithal or the willingness to devote time and resources to strategy formulation but are focused to reconsider this position by the pressures of globalization.

Through a literature survey, a model suitable for SMEs is identified. An application of the selected model is presented. Applicability of strategic tools such as ERP in SMEs is examined. A case of a company, which has implemented ERP is analyzed.

SMEs need strategy but the strategy depends on the complexity of the process. The case study points to the need for top management support and commitment.

It is difficult to get financial data from individual SMEs as most SMEs are proprietorship concerns.

For countries, which are labor surplus, study on SMEs which are not capital intensive but create employment, has practical and social implication.

This paper attempts at filling research gaps on competitive strategies for SMEs.

The purpose of this paper is to examine the influence of cognition on knowledge sharing between members of the acquiring and acquired organisations in the post-acquisition integration process. It specifically analyses differentiation between in-groups and out-groups, the perception of organisational identity and interaction among members of the acquired and acquiring organisations and how these three factors affect knowledge sharing.

The authors develop theoretical propositions and conduct an explorative pilot study on the basis of original interview data conducted with ten respondents in four Indian IT companies that have acquired firms abroad.

The authors find evidence for supporting the negative effect of in- and out-groups differentiation and the positive effect of interpersonal interaction on knowledge sharing among employees of the acquired and acquiring organisations. There was indicative, but less compelling, evidence for the negative influence of inter-group competition and the positive influence of perceived shared organisational identity on knowledge sharing. Different from the established view, the authors find that when Indian firms acquire firms abroad, they immediately initiate knowledge flows from the targets rather than going through a long period of integration prior to acquiring knowledge from the targets.

The paper contributes to the scholarly conversation on cognition and knowledge sharing and argues that firms that are located in developing economies and that acquire firms abroad behave in a way somewhat different from what Western literature postulates. This invites for further studies, both theoretical and empirical, to shed light on this phenomenon. The present paper is focused only on one country, India, and on a single industry, the IT industry. It is limited in its empirical part, mainly due to enormous difficulties in getting access to the field.

The study demonstrates how central individuals are to the process of knowledge sharing and the accomplishment of organisational objectives in a post-acquisition context. Managers should understand that the knowledge their employees possess is a strategic asset, and therefore how they use it is influential in attaining organisational goals in general, and acquisition integration objectives in particular. The creation of task- and project-related communities or groups can help in establishing a shared organisational identity, especially after the turbulent event of one company acquiring another one. The creation of communities or groups where socialisation is encouraged can lead to employees interacting with one another and developing a sense of belongingness with the community or group. Over time, this belongingness can translate into a shared organisational identity, which is beneficial for the organisation. The findings suggest that the creation of task- or project-oriented communities and groups is a powerful way to achieve that.

The contribution of the paper is fourfold. First, while macro orientation dominates literature on the growth of the Indian IT industry, this study is conducted at the individual level of analysis, by focusing on managers in acquiring Indian IT firms. Second, whereas studies that have examined cognition and knowledge sharing have done so mainly through social capital lenses, this paper focuses on factors that are based on the inherent tendency of human beings to categorise themselves and other individuals. Third, the paper examines the links between cognition and knowledge sharing in an exciting context, namely, post-acquisition integration. Finally, while research on both post-acquisition integration and knowledge sharing is biased towards a Western context, this study investigates knowledge sharing and post-acquisition integration in the context of a major non-Western emerging economy.