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Article
Publication date: 4 September 2020

M. Vykunta Rao, Srinivasa Rao P. and B. Surendra Babu

Vibratory weld conditioning parameters have a great influence on the improvement of mechanical properties of weld connections. The purpose of this paper is to understand…

Abstract

Purpose

Vibratory weld conditioning parameters have a great influence on the improvement of mechanical properties of weld connections. The purpose of this paper is to understand the influence of vibratory weld conditioning on the mechanical and microstructural characterization of aluminum 5052 alloy weldments. An attempt is made to understand the effect of the vibratory tungsten inert gas (TIG) welding process parameters on the hardness, ultimate tensile strength and microstructure of Al 5052-H32 alloy weldments.

Design/methodology/approach

Aluminum 5052 H32 specimens are welded at different combinations of vibromotor voltage inputs and time of vibrations. Voltage input is varied from 50 to 230 V at an interval of 10 V. At each voltage input to the vibromotor, there are three levels of time of vibration, i.e. 80, 90 and 100 s. The vibratory TIG-welded specimens are tested for their mechanical and microstructural properties.

Findings

The results indicate that the mechanical properties of aluminum alloy weld connections improved by increasing voltage input up to 160 V. Also, it has been observed that by increasing vibromotor voltage input beyond 160 V, mechanical properties were reduced significantly. It is also found that vibration time has less influence on the mechanical properties of weld connections. Improvement in hardness and ultimate tensile strength of vibratory welded joints is 16 and 14%, respectively, when compared without vibration, i.e. normal weld conditions. Average grain size is measured as per ASTM E 112–96. Average grain size is in the case of 0, 120, 160 and 230 is 20.709, 17.99, 16.57 and 20.8086 µm, respectively.

Originality/value

Novel vibratory TIG welded joints are prepared. Mechanical and micro-structural properties are tested.

Details

World Journal of Engineering, vol. 17 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 16 September 2020

Venkata Suresh Bade, Srinivasa Rao P. and Govinda Rao P.

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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

Details

World Journal of Engineering, vol. 17 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 February 1997

Masoud Hemmasi, Lee A. Graf and Michael R. Williams

With U.S. health care costs increasing at three times the rate of inflation and Americans spending 50 percent more on health care than any other nation, health care…

Abstract

With U.S. health care costs increasing at three times the rate of inflation and Americans spending 50 percent more on health care than any other nation, health care practitioners will most certainly continue to focus upon cost containment and budgets (Guthrie, 1991). However, as suggested by some experts (e.g. Lytle and Mokwa, 1992), managerial approaches preoccupied with containing costs and financial budgeting are no longer sufficient for success, or maybe even survival, in today's intensely competitive marketplace. The major transformations in structure that have taken place in the health care industry throughout the 1980s call for more proactive and strategic approaches to planning and managing if health care organizations are to be successful in today's highly competitive environment.

Details

Competitiveness Review: An International Business Journal, vol. 7 no. 2
Type: Research Article
ISSN: 1059-5422

Article
Publication date: 1 February 1990

C.P. Rao, M. Krishna Erramilli and Gopala K. Ganesh

Why does a recession in the domestic market lead to a modificationof the firm′s export marketing behaviour? Based on an empirical studywhich investigated the behaviour of…

Abstract

Why does a recession in the domestic market lead to a modification of the firm′s export marketing behaviour? Based on an empirical study which investigated the behaviour of United States exporters during the 1980‐82 recession, evidence is provided which suggests that many firms which were adversely affected by the recession intensified their exports, and that these firms significantly modified their export marketing activities. The evidence also suggests that exporting firms change their export destinations during recessions. Finally, the factors which facilitated and inhibited export expansion during the recession are also examined.

Details

International Marketing Review, vol. 7 no. 2
Type: Research Article
ISSN: 0265-1335

Keywords

Article
Publication date: 28 November 2018

M.A. Mushahhid Majeed and Sreehari Rao Patri

This paper aims to resolve the sizing issues of analog circuit design by using proposed metaheuristic optimization algorithm.

Abstract

Purpose

This paper aims to resolve the sizing issues of analog circuit design by using proposed metaheuristic optimization algorithm.

Design/methodology/approach

The hybridization of whale optimization algorithm and modified gray wolf optimization (WOA-mGWO) algorithm is proposed, and the same is applied for the automated design of analog circuits.

Findings

The proposed hybrid WOA-mGWO algorithm demonstrates better performance in terms of convergence rates and average fitness of the function after testing it with 23 classical benchmark functions. Moreover, a rigorous performance evaluation is done with 20 independent runs using Wilcoxon rank-sum test.

Practical implications

For evaluating the performance of the proposed algorithm, a conventional two-stage operational amplifier is considered. The aspect ratios calculated by simulating the algorithm in MATLAB are later used to design the operational amplifier in Cadence environment using 180nm CMOS standard process.

Originality/value

The hybrid WOA-mGWO algorithm is tailored to improve the exploration ability of the algorithm by combining the abilities of two metaheristic algorithms, i.e. whale optimization algorithm and modified gray wolf optimization algorithm. To build further credence and to prove its profound existence in the latest state of the art, a statistical study is also conducted over 20 independent runs, for the robustness of the proposed algorithm, resulting in best, mean and worst solutions for analog IC sizing problem. A comparison of the best solution with other significant sizing tools proving the efficiency of hybrid WOA-mGWO algorithm is also provided. Montecarlo simulation and corner analysis are also performed to validate the endurance of the design.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 38 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Book part
Publication date: 17 January 2022

Samppa Kamara, Ahmad Arslan and Desislava Dikova

The current chapter is one of the first studies to specifically address the role of civil society organisations (CSOs) for entrepreneurship development in the…

Abstract

The current chapter is one of the first studies to specifically address the role of civil society organisations (CSOs) for entrepreneurship development in the disadvantaged context of Sierra Leone. It highlights the important role of CSOs in the petty trading (disadvantaged) entrepreneurial ecosystem. Based on qualitative analysis of interviewers undertaken with two CSOs and three entrepreneurial firms from disadvantaged backgrounds, our findings offer interesting insights into this phenomenon. The authors find that in the context of disadvantaged entrepreneurship development, CSOs are seen as more trustworthy by the general population than the government (public bodies). The government, through the national youth commission, also tried to collaborate with CSOs regarding entrepreneurial skills development in disadvantaged entrepreneurs. The findings further reveal that despite the appreciation of the role of CSOs for disadvantaged entrepreneurship development by public authorities in recent years, they still face many bureaucratic hurdles and delays in operations. Finally, our chapter reveals several dynamics associated with skills and competencies development in disadvantaged entrepreneurship in the Sierra Leone-specific context, where skills such as basic business planning, livestock handling, and financial management emerge as being highly useful.

Details

Disadvantaged Entrepreneurship and the Entrepreneurial Ecosystem
Type: Book
ISBN: 978-1-80071-450-2

Keywords

Book part
Publication date: 29 March 2016

Marc Wouters, Susana Morales, Sven Grollmuss and Michael Scheer

The paper provides an overview of research published in the innovation and operations management (IOM) literature on 15 methods for cost management in new product…

Abstract

Purpose

The paper provides an overview of research published in the innovation and operations management (IOM) literature on 15 methods for cost management in new product development, and it provides a comparison to an earlier review of the management accounting (MA) literature (Wouters & Morales, 2014).

Methodology/approach

This structured literature search covers papers published in 23 journals in IOM in the period 1990–2014.

Findings

The search yielded a sample of 208 unique papers with 275 results (one paper could refer to multiple cost management methods). The top 3 methods are modular design, component commonality, and product platforms, with 115 results (42%) together. In the MA literature, these three methods accounted for 29%, but target costing was the most researched cost management method by far (26%). Simulation is the most frequently used research method in the IOM literature, whereas this was averagely used in the MA literature; qualitative studies were the most frequently used research method in the MA literature, whereas this was averagely used in the IOM literature. We found a lot of papers presenting practical approaches or decision models as a further development of a particular cost management method, which is a clear difference from the MA literature.

Research limitations/implications

This review focused on the same cost management methods, and future research could also consider other cost management methods which are likely to be more important in the IOM literature compared to the MA literature. Future research could also investigate innovative cost management practices in more detail through longitudinal case studies.

Originality/value

This review of research on methods for cost management published outside the MA literature provides an overview for MA researchers. It highlights key differences between both literatures in their research of the same cost management methods.

Article
Publication date: 21 May 2020

Venkata Suresh Bade, Srinivasa Rao P. and Govinda Rao P.

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

World Journal of Engineering, vol. 17 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Book part
Publication date: 25 September 2017

Suraksha Gupta

Intentions of managers of pharmaceutical multinational enterprises (MNEs) to adopt business strategies, which will aid global health and wellbeing, are in some ways linked…

Abstract

Intentions of managers of pharmaceutical multinational enterprises (MNEs) to adopt business strategies, which will aid global health and wellbeing, are in some ways linked with their understanding of the returns that their company will receive from these investments. However, the MNE’s managers are unaware of business strategies that will allow them to link their business activities with the corporate objectives of contributing to Sustainable Development Goals (SDGs). Pharmaceutical companies are moving toward monopolistic practices by acquiring local companies for manufacturing purposes or by engaging local companies in contract manufacturing and directing the focus of these companies away from innovation and toward profit making. At the same time, pharmaceutical MNEs are promoting global health and wellbeing as their SDGs. This study uses knowledge from existing sources and expert insights to explain the returns that MNEs can get from their investments related to global health and wellbeing. One of the important recommendations from the ethical point of view is engaging local firms in the innovation process; from the marketing perspective, this study recommends the use of a corporate brand and not a product brand for offering generic medicines. The operations perspective explains how MNEs can incorporate the social agenda into their mainstream business strategies. Limitations of the study are discussed, and avenues for future research are explained.

Details

Multinational Enterprises and Sustainable Development
Type: Book
ISBN: 978-1-78743-163-8

Keywords

Book part
Publication date: 25 September 2017

Pervez N. Ghauri, Xiaolan Fu and Juha Väätänen

The relationship between multinational enterprises (MNEs) and host governments has seen different waves of trust and mistrust. Over the years, it has changed from a period…

Abstract

The relationship between multinational enterprises (MNEs) and host governments has seen different waves of trust and mistrust. Over the years, it has changed from a period of conflict after World War II, where MNEs were investing for purposes felt to be contradictory to government policies, to a more cooperative one, where countries are providing incentives and competing with each other to attract foreign direct investment (FDI). The 1990s saw the cooperative relationship leading to the danger of race to the bottom through excessive locational competition. In this chapter, we look at the past, present, and future state of this relationship as reported by different scholars from these periods. We look at the most influential literature from the 1970s onward and the current state of this relationship. Our analysis reveals that the increased tensions are caused by anxiety owing to unanticipated developments in the political economy, company strategies, and government policies. Thanks to globalization MNEs are increasingly becoming more powerful and often this process is accelerated owing to lack of any collaboration between MNEs and the governments. Thus, governments, particularly in emerging markets, are becoming more and more frustrated by the fact that on the one hand they want the MNEs to come and invest in their countries and, on the other hand, they feel that they cannot direct these MNEs to contribute toward economic development and poverty alleviation in their countries. In this chapter, we intend to evaluate the past and the present literature and look ahead to the future. Finally, on the basis of our own studies performed in this project and reported in different chapters of this book, we provide some policy guidelines for host country governments as to how they can encourage MNEs to contribute toward sustainable development and poverty reduction.

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