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Article
Publication date: 16 August 2021

Mahendra Pratap, Anil Kumar Agrawal, Subhash Chandra Sati and Arun Kumar Saxena

The purpose of this paper is to improve the design of a solid square canopy of a parachute. The design improvements are brought out by providing minor slits in the canopy area…

175

Abstract

Purpose

The purpose of this paper is to improve the design of a solid square canopy of a parachute. The design improvements are brought out by providing minor slits in the canopy area. Proper designing of the parachute was carried out using theoretical investigation coupled with experimentation. This parachute is designed for launch of sonobuoy from fixed wing aircraft.

Design/methodology/approach

Literature review was carried out on the design of such parachutes for the launch of a sonobuoy from a high altitude to the water entry. Computational fluid dynamics (CFD) analysis provided the value of the coefficient of drag for the slit-cut square canopy parachute, with and without sonobuoy for different lengths of the slit. Besides the theoretical investigation, experimentation was also carried out to validate the design.

Findings

The experimentation was carried out on 58 and 75 gsm fabric canopies with the slit edge plain-cut with thermally sealed edges, stitched and strengthened. In the case of plain-cut slits on the canopy made of 75 gsm fabric, no tearing of the slit edge was observed in dynamic and flight tests.

Research limitations/implications

The present work has been carried out considering various assumptions and limited trial data specific to precision drop of 9 kg payload. The work can be adopted for bigger parachute for dropping of higher payloads.

Originality/value

Lab strength test, track dynamic and flight trials were conducted to acquire useful data for the present analysis. Besides the theoretical investigations and CFD analysis inherently based on numerous assumptions, experimentation was carried out as the sonobuoy deployment conditions are full of uncertainty. Dynamic and airdrop tests were conducted for this reason to determine design changes in the slits, both at the material level and on improvisations.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 10
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 29 June 2020

Anil Kumar Agrawal, Mahendra Pratap, Subhash Chandra Sati and Rajeev Kumar Upadhyay

The purpose of this paper is to optimize the design of a hybrid tether using probabilistic approach considering inherent random variation in the stress developed and the strength…

124

Abstract

Purpose

The purpose of this paper is to optimize the design of a hybrid tether using probabilistic approach considering inherent random variation in the stress developed and the strength it has. The variation in strength is mostly because of variation in diameter of the tether and the properties of the material along the length of the tether. As a result, classical design approach for the tether may not serve the purpose. For this purpose, a reliability-based design of hybrid tether is discussed in this paper.

Design/methodology/approach

A literature review was carried out on the design of tether and its operational reliability. It has been shown that the classical design approach does not serve the purpose, as the strategic operation has to be reliable enough, often requiring a measure of reliability required. A reliability-based approach has been presented to achieve the optimum design of a hybrid tether.

Findings

The optimization problem was carried out for different values of the safety factor to investigate the effect on the optimal design of tether. An analysis is carried out to show that one should not target a very high value of reliability or factor of safety, as it causes the self-weight of the tether to increase tremendously and its cost significantly.

Research limitations/implications

The present work has been carried out considering the limited data and can further be extended to determine more accurate reliability measures by considering more number of sample test data. The measured data is collected from limited required trials for demo; do not represent the exact population data.

Originality/value

Lab strength test and flight trials were conducted to acquire data for the present analysis. In field use, it was noticed that the tether degraded from top portion attached toward the balloon end because of maximum exposure and repeated usage.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 8
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 4 September 2017

Sagar Sikder, Subhash Chandra Panja and Indrajit Mukherjee

The purpose of this paper is to develop a new easy-to-implement distribution-free integrated multivariate statistical process control (MSPC) approach with an ability to recognize…

482

Abstract

Purpose

The purpose of this paper is to develop a new easy-to-implement distribution-free integrated multivariate statistical process control (MSPC) approach with an ability to recognize out-of-control points, identify the key influential variable for the out-of-control state, and determine necessary changes to achieve the state of statistical control.

Design/methodology/approach

The proposed approach integrates the control chart technique, the Mahalanobis-Taguchi System concept, the Andrews function plot, and nonlinear optimization for multivariate process control. Mahalanobis distance, Taguchi’s orthogonal array, and the main effect plot concept are used to identify the key influential variable responsible for the out-of-control situation. The Andrews function plot and nonlinear optimization help to identify direction and necessary correction to regain the state of statistical control. Finally, two different real life case studies illustrate the suitability of the approach.

Findings

The case studies illustrate the potential of the proposed integrated multivariate process control approach for easy implementation in varied manufacturing and process industries. In addition, the case studies also reveal that the multivariate out-of-control state is primarily contributed by a single influential variable.

Research limitations/implications

The approach is limited to the situation in which a single influential variable contributes to out-of-control situation. The number and type of cases used are also limited and thus generalization may not be debated. Further research is necessary with varied case situations to refine the approach and prove its extensive applicability.

Practical implications

The proposed approach does not require multivariate normality assumption and thus provides greater flexibility for the industry practitioners. The approach is also easy to implement and requires minimal programming effort. A simple application Microsoft Excel is suitable for online implementation of this approach.

Originality/value

The key steps of the MSPC approach are identifying the out-of-control point, diagnosing the out-of-control point, identifying the “influential” variable responsible for the out-of-control state, and determining the necessary direction and the amount of adjustment required to achieve the state of control. Most of the approaches reported in open literature are focused only until identifying influencing variable, with many restrictive assumptions. This paper addresses all key steps in a single integrated distribution-free approach, which is easy to implement in real time.

Details

International Journal of Quality & Reliability Management, vol. 34 no. 8
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 31 May 2024

Monojit Das, V.N.A. Naikan and Subhash Chandra Panja

The aim of this paper is to review the literature on the prediction of cutting tool life. Tool life is typically estimated by predicting the time to reach the threshold flank wear…

209

Abstract

Purpose

The aim of this paper is to review the literature on the prediction of cutting tool life. Tool life is typically estimated by predicting the time to reach the threshold flank wear width. The cutting tool is a crucial component in any machining process, and its failure affects the manufacturing process adversely. The prediction of cutting tool life by considering several factors that affect tool life is crucial to managing quality, cost, availability and waste in machining processes.

Design/methodology/approach

This study has undertaken the critical analysis and summarisation of various techniques used in the literature for predicting the life or remaining useful life (RUL) of the cutting tool through monitoring the tool wear, primarily flank wear. The experimental setups that comprise diversified machining processes, including turning, milling, drilling, boring and slotting, are covered in this review.

Findings

Cutting tool life is a stochastic variable. Tool failure depends on various factors, including the type and material of the cutting tool, work material, cutting conditions and machine tool. Thus, the life of the cutting tool for a particular experimental setup must be modelled by considering the cutting parameters.

Originality/value

This submission discusses tool life prediction comprehensively, from monitoring tool wear, primarily flank wear, to modelling tool life, and this type of comprehensive review on cutting tool life prediction has not been reported in the literature till now. The future suggestions provided in this review are expected to provide avenues to solve the unexplored challenges in this field.

Details

International Journal of Quality & Reliability Management, vol. 42 no. 2
Type: Research Article
ISSN: 0265-671X

Keywords

Available. Open Access. Open Access

Abstract

Details

Asian Association of Open Universities Journal, vol. 9 no. 1
Type: Research Article
ISSN: 1858-3431

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Article
Publication date: 4 February 2014

Subhash Chandra Sharma and Doug Hargreaves

Ideally, there is no wear in hydrodynamic lubrication regime. A small amount of wear occurs during start and stop of the machines and the amount of wear is so small that it is…

482

Abstract

Purpose

Ideally, there is no wear in hydrodynamic lubrication regime. A small amount of wear occurs during start and stop of the machines and the amount of wear is so small that it is difficult to measure with accuracy. Various wear measuring techniques have been used where out-of-roundness was found to be the most reliable method of measuring small wear quantities in journal bearings. This technique was further developed to achieve higher accuracy in measuring small wear quantities. The method proved to be reliable as well as inexpensive. The paper aims to discuss these issues.

Design/methodology/approach

In an experimental study, the effect of antiwear additives was studied on journal bearings lubricated with oil containing solid contaminants. The test duration was too long and the wear quantities achieved were too small. To minimise the test duration, short tests of about 90 min duration were conducted and wear was measured recording changes in variety of parameters related to weight, geometry and wear debris. The out-of-roundness was found to be the most effective method. This method was further refined by enlarging the out-of-roundness traces on a photocopier. The method was proved to be reliable and inexpensive.

Findings

Study revealed that the most commonly used wear measurement techniques such as weight loss, roughness changes and change in particle count were not adequate for measuring small wear quantities in journal bearings. Out-of-roundness method with some refinements was found to be one of the most reliable methods for measuring small wear quantities in journal bearings working in hydrodynamic lubrication regime. By enlarging the out-of-roundness traces and determining the worn area of the bearing cross-section, weight loss in bearings was calculated, which was repeatable and reliable.

Research limitations/implications

This research is a basic in nature where a rudimentary solution has been developed for measuring small wear quantities in rotary devices such as journal bearings. The method requires enlarging traces on a photocopier and determining the shape of the worn area on an out-of-roundness trace on a transparency, which is a simple but a crude method. This may require an automated procedure to determine the weight loss from the out-of-roundness traces directly. This method can be very useful in reducing test duration and measuring wear quantities with higher precision in situations where wear quantities are very small.

Practical implications

This research provides a reliable method of measuring wear of circular geometry. The Talyrond equipment used for measuring the change in out-of-roundness due to wear of bearings indicates that this equipment has high potential to be used as a wear measuring device also. Measurement of weight loss from the traces is an enhanced capability of this equipment and this research may lead to the development of a modified version of Talyrond type of equipment for wear measurements in circular machine components.

Originality/value

Wear measurement in hydrodynamic bearings requires long duration tests to achieve adequate wear quantities. Out-of-roundness is one of the geometrical parameters that changes with progression of wear in a circular shape components. Thus, out-of-roundness is found to be an effective wear measuring parameter that relates to change in geometry. Method of increasing the sensitivity and enlargement of out-of-roundness traces is original work through which area of worn cross-section can be determined and weight loss can be derived for materials of known density with higher precision.

Details

Industrial Lubrication and Tribology, vol. 66 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 18 September 2020

Thibault Weigelt and Erica Sharma

The purpose of this paper is to analyse the budget of the Indian family planning programme from a human rights perspective. Family planning services play an important role in the…

176

Abstract

Purpose

The purpose of this paper is to analyse the budget of the Indian family planning programme from a human rights perspective. Family planning services play an important role in the realisation of the reproductive rights of women. In India, the family planning programme is one of the largest in the world with thousands of patients, mostly women, accessing services every year. Although the Indian legal system guarantees the right to health, Indian women from marginalised sections of society still battle inadequate services and the absence of health care that respects their right to reproductive autonomy and choice. Therefore, the question is: in the presence of a strong legal framework, what are the factors that contribute to this phenomenon?

Design/methodology/approach

The authors have gathered data from the project implementation plans at the state level comparing year-wise expenditure for family planning against overall expenditure for reproductive, maternal and child health expenditure. The data are then compared to the number of women using sterilisation to suggest a relationship between both. Finally, the article relies on desk research to review scholarship on the Indian family planning programme and applicable human rights obligations.

Findings

The paper finds that social-economic rights such as the right to health are applicable to government spending and budgeting. It also finds current spending in the NHM is insufficient to guarantee women’s reproductive rights as the vast majority of resources are spend on sterilisation, thus limiting women’s ability to choose the number and spacing of children.

Research limitations/implications

The data used in this research bears one limitation: the propensity of the government to change the guidelines as to how States should present their budgets in the project implementation plans. The authors have adjusted the data so that it remains comparable. However, the adjustment was not possible for all expenditure data, which is why the current study is limited to the family planning programme alone.

Practical implications

The paper argues that to be human rights compliant, health budgets of the NHM need to be geared towards the specific needs of women in terms of family planning. Finally, the article briefly outlines the role played by human rights and human rights litigation in impacting government budgets.

Originality/value

India’s family planning programme has been examined from a performance and medical standpoint, focussing on medical indicators such as total fertility rate, unmet needs for family planning, amongst others. Academic scholarship has investigated through statistical analysis patterns of contraceptive use and contraceptive mix. What is absent, however, is an assessment of the programme from a right-based perspective by looking at the human rights obligations of India and their normative implications for the Indian family programme.

Details

International Journal of Human Rights in Healthcare, vol. 13 no. 4
Type: Research Article
ISSN: 2056-4902

Keywords

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Book part
Publication date: 11 November 2019

Sunil Kumar Sharma, Atri Sengupta and Subhash Chandra Panja

Grounded theory (GT) is a very crucial qualitative tool in research inquiry. It embraces systematic, inductive, and comparative inquiry method to construct a theory. GT is mostly…

Abstract

Grounded theory (GT) is a very crucial qualitative tool in research inquiry. It embraces systematic, inductive, and comparative inquiry method to construct a theory. GT is mostly appropriate to investigate organizational phenomena, which involves a change process. In this chapter, the authors focus on the emergence of GT as a research inquiry tool with the focus how GT evolves from classis grounded theory to constructivist ground theory. In the detailed method of GT, a focus is given on coding method along with theoretical sampling and theoretical saturation points. Despite being a powerful technique, GT has drawn a number of criticisms. Majority GT researchers consider the technique as an inductive method with a few exceptions, where it has been deliberated as a deductive method. However, in the line of Corley (2015), it can be argued that GT should be considered as a methodological approach to study inductive phenomena having less understanding of theoretical perspective. Chapter concludes with identifying future scope of study in the field of GT.

Details

Methodological Issues in Management Research: Advances, Challenges, and the Way Ahead
Type: Book
ISBN: 978-1-78973-973-2

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Article
Publication date: 2 May 2008

Shamas‐ur‐Rehman Toor and George Ofori

Recent research on leadership has focused on the exploration of the taxonomies of leadership antecedents (or “trigger events”) that significantly influence the development of the…

2338

Abstract

Purpose

Recent research on leadership has focused on the exploration of the taxonomies of leadership antecedents (or “trigger events”) that significantly influence the development of the attributes of leadership in individuals. These leadership antecedents – which may involve individuals, social institutions, and life experiences – constitute a worthwhile topic for research. This paper aims to report a study which explores the leadership antecedents that inspired leadership development among graduate project management students.

Design/methodology/approach

To ascertain the significance of leadership antecedents, a study was conducted at National University of Singapore. A questionnaire survey was used to collect data on taxonomies of various leadership antecedents which contributed to the development of leadership skills among the subjects. Of a total of 90 questionnaires, which were distributed, 58 completed questionnaires were received.

Findings

The results suggest that teachers, parents, and mentors are significant in the development of leadership among the emergent leaders. It was also noted that educational and occupational experiences play a central role in leadership development. Future studies can use qualitative approaches, especially grounded theory methodology, to develop comprehensive frameworks explaining leadership development process.

Research limitations/implications

The results of this exploratory study can form the basis for further work in the field of leadership development.

Originality/value

The taxonomy of leadership antecedents employed in this study can be used to design controlled interventions for leadership development in emergent project leaders and project management trainees.

Details

Engineering, Construction and Architectural Management, vol. 15 no. 3
Type: Research Article
ISSN: 0969-9988

Keywords

Available. Content available
Book part
Publication date: 11 November 2019

Abstract

Details

Methodological Issues in Management Research: Advances, Challenges, and the Way Ahead
Type: Book
ISBN: 978-1-78973-973-2

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