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The purpose of this paper is to propose and develop PA2200-based composite powder containing 0-15 Wt.% magnesium oxide before directly using it in selective laser sintering (SLS) machine to produce end-use products for low-volume production in the engineering applications with keen focus to meet the functional requirements which rely on material properties.

The methodology reported emphasises PA2200-based composite powder containing 0-15 Wt.% magnesium oxide development for SLS process which starts with preparation and characterisation of composite material, thermal and rheological study of composite material to decide optimum process parameters for SLS process machine to get optimal part properties. Further, to verify composite material properties, a conventional casting methodology is used. The composition of composite materials those possessing good properties are further selected for processing in SLS process under optimal processing parameters.

The process parameters of SLS machine are material-dependent. The effect of temperature in X-ray diffraction profile is negligible in the case of magnesium oxide reinforced PA2200 composite material. The cyclic heating of material increases melting point temperature, this grounds to modify part bed temperature of material every time before processing on SLS machine to uphold build part properties, as well as material. With the rise in temperature, the Melt flow index and rheological property of materials change. The magnesium oxide reinforced PA2200 composite material has high thermal stability than pure PA2200 material. By the addition of small quantity of magnesium oxide, most of the mechanical property and flammability property improves while elongation at break (percentage) decreases significantly.

The proposed PA2200-based composite powder containing 0-15 Wt.% magnesium oxide material development system and casting metrology to verify developed material properties will be very useful to develop new composite material for SLS process with use of less material. The developed methodology has proven, especially in the case where non-experts or student need to develop composite material for SLS process according to the property requirement of applications.

Unlike earlier composite material development methodology, the projected methodology of polymer-based composite material and confirmation of material properties instead of commencing SLS process provides straight forward means for SLS process composite materials development with less use of the material and period of time.

This paper aims to investigate the specific tea tourism (TT) determinants. This paper uses the Porter’s Diamond model to critically examine how India and Sri Lanka gained a competitive advantage in the international market.

A cross-country study was conducted in which TT destinations in both India and Sri Lanka were considered for study. TT stakeholder perspectives were assessed through the Porter Diamond model, whereas data collection was based on a structured questionnaire that adopted the conceptual model (refer to the questionnaire as annex 1).

This study revealed that each determinant of Porter’s Diamond model (i.e. Factor Conditions – FC, Demand Conditions – DC, Related and Supporting Industry – RSI, Firm Strategy, Structure and Rivalry – SSR, Government – GO and Situational Force – SF) is playing a significant role in TT and India has an edge on Sri Lanka as a TT destination over each determinant of Porter Diamond model.

This study restricts its scope to the present TT stakeholders of India and Sri Lanka, comprising 6 latent variables and 31 indicators, offering opportunities for future research to tourists and local residents in TT using the same model variables, and indicators.

This study highlights the emerging TT destinations in India and Sri Lanka by sensitizing the competitiveness and comparativeness using Porter’s Diamond model through the partial least squares structural equation modeling.

This study reflects a unique way of exploring emerging TT destinations through Porter’s Diamond model, signifying the competitive advantage.

为了研究茶旅游的具体决定因素, 本文采用波特钻石模型批判性地检验印度和斯里兰卡如何在国际市场上获得竞争优势。

以印度和斯里兰卡作为茶旅游目的地进行的一项跨国研究。基于一项结构化问卷（附件1）进行数据收集, 并通过波特钻石模型评估茶旅游利益相关者的观点。

研究表明, 波特钻石模型的每个决定因素：因子条件（FC）、需求条件（DC）、相关和支持产业（RSI）、企业战略、结构和竞争（SSR）、政府（GO）和情境力量（SF）都在茶旅游中发挥着重要作用。作为茶旅游目的地, 印度比斯里兰卡在波特钻石模型的每个决定因素方面都更具有优势。

目前的研究范围仅限于印度和斯里兰卡目前的茶旅游利益相关者, 包括六个潜在变量和31个指标, 为未来研究茶旅游中游客和当地居民的未来研究使用相同的模型变量和指标提供了可能。

本研究使用波特钻石模型和PLS-SEM模型来突出印度和斯里兰卡作为新兴茶旅游目的地的竞争力和可比性。

这项研究展现了一种通过波特钻石模型来探索新兴茶旅游目的地的独特方法, 表明了它的竞争优势。

Para investigar los determinantes específicos del turismo del té, el documento actual emplea el modelo del Diamante de Porter, examinando de forma crítica, cómo India y Sri Lanka obtuvieron una ventaja competitiva en el mercado internacional.

Este estudio se llevó a cabo en dos destinos turísticos del té como India y Sri Lanka. Las perspectivas de las partes interesadas en el turismo del té se evaluaron a través del modelo del Diamante de Porter, mientras que la recopilación de datos se basó en un cuestionario estructurado, adaptado del modelo conceptual (consulte el cuestionario como anexo 1).

El estudio reveló que cada determinante del modelo del Diamante de Porter; Las condiciones de los factores (FC), las condiciones de la demanda (DC), la industria relacionada y de apoyo (RSI), la estrategia, la estructura y la rivalidad de la empresa (SSR), el gobierno (GO) y la fuerza situacional (SF) están desempeñando un papel importante en el turismo del té e India tiene una ventaja sobre Sri Lanka como destino de turismo de té sobre cada determinante del modelo de Porter.

El estudio actual restringe su alcance a las partes interesadas en el turismo del té de la India y Sri Lanka, que comprende seis variables latentes y 31 indicadores, ofreciendo oportunidades para futuras investigaciones a los turistas y residentes locales en el turismo del té utilizando las mismas variables e indicadores del modelo.

El presente estudio destaca los destinos emergentes del turismo del té en India y Sri Lanka, sensibilizando la competitividad y la comparabilidad, utilizando el modelo del diamante de Porter y el modelo PLS-SEM.

Este estudio refleja una forma única de explorar los destinos emergentes del turismo del té a través del modelo de diamante de Porter, lo que significa la ventaja competitiva.

The purpose of this paper is to develop a multi-item economic production quantity (EPQ) strategy under grey environment and space constraint. Since the “demand” cannot be predicted with certainty, it is assumed that data behave under grey environment and compare the proposed inventory model with other studies using crisp or fuzzy environments.

This paper is to optimise the cycle time and total cost of the multi-item EPQ inventory model. For this purpose, the Lagrangian coefficient is used to solve the constrained optimisation problem. The grey relational analysis approach and grey data are applied in developing the EPQ inventory model.

The results are compared with the analysis using crisp and fuzzy data. Sensitivity analysis is done to illustrate the effect of parameter variations on the optimal solution. The results of the study demonstrate that crisp data outperform the other two data in all scales problems in terms of cycle time and cost; grey data perform better in all scales problems than fuzzy data.

The contribution of this research is the use of grey data in developing the EPQ inventory model with space constraint.

The main objective of this research is to investigate if there is a long-term relationship between “terrorism” and sustainable “economic growth” in Big Ten Countries.

The data was tested via Panel ARDL Analysis. The growth rate (GR) is the dependent variable, and the “Global Terror Index (GTI)” is the independent variable as the terror indicator. The ratio of Foreign Direct Investment (FDI) to the Gross Domestic Product (GDP), and the ratio of External Balance (EB) to Gross Domestic Product (GDP) are included in the model as the control variables due to their effect on the growth rate. A Panel ARDL analysis is conducted to examine the existence of long-term co-integration between terror and the economy. The planning of the study, the formation of its theoretical and conceptual framework, and the literature research were carried out in 2 months, and the collection of data, the creation of the methodology and the analysis of the analyzes were carried out in 2 months, the interpretation of the findings and the development of policy recommendations were carried out within a period of 1 month. The entire study was completed in a total of 5 months.

Results showed that “Terror” has a negative impact on “Growth Rate” in the long term while “External Balance” and “Foreign Direct Investment” positively affect the Growth Rate. The coefficients for the short term are not statistically significant.

The sample is only limited to Big Ten including China, India, Indonesia, South Korea, Argentina, Brazil, Mexico, Turkey, Poland and South Africa. The period for annual data collection covers the years between 2002 and 2019 and due to the unavailability of data.

Considering the risks and the mutual negative effect that turns into a vicious circle between terrorism and the economy, it is necessary to eliminate the problems that cause terrorism in the mentioned countries, on the one hand, and to develop policies that will improve economic performance on the other.

Trustful law enforcement bodies have to be established and supported by all technological means to prevent terror. The conditions causing terror have to be investigated carefully and the problems causing terror or internal conflict have to be solved. International cooperation against terrorism has to be strengthened and partnerships, information, experience sharing have to be supported at the maximum levels.

It is certain that terror might have a negative influence on the performance of economies. But the limited number of studies within this vein and the small size of their sample groups mostly including single-country case studies require conducting a study by using a larger sample group of countries. Big Ten here represents at least half of the population of the world and different regions of the Globe.

The purpose of this paper is to propose and evaluate the selection of materials for the selective laser sintering (SLS) process, which is used for low-volume production in the engineering (e.g. light weight machines, architectural modelling, high performance application, manufacturing of fuel cell, etc.), medical and many others (e.g. art and hobbies, etc.) with a keen focus on meeting customer requirements.

The work starts with understanding the optimal process parameters, an appropriate consolidation mechanism to control microstructure, and selection of appropriate materials satisfying the property requirement for specific application area that leads to optimization of materials.

Fabricating the parts using optimal process parameters, appropriate consolidation mechanism and selecting the appropriate material considering the property requirement of applications can improve part characteristics, increase acceptability, sustainability, life cycle and reliability of the SLS-fabricated parts.

The newly proposed material selection system based on properties requirement of applications has been proven, especially in cases where non-experts or student need to select SLS process materials according to the property requirement of applications. The selection of materials based on property requirement of application may be used by practitioners from not only the engineering field, medical field and many others like art and hobbies but also academics who wish to select materials of SLS process for different applications.

The purpose of this paper is to capture the status of implementation of Six Sigma in various manufacturing industries and also examine the success of the Six Sigma by using different performance indicators.

The methodology of critical review involves the selection and classification of 112 research articles on the implementation of Six Sigma in different manufacturing industries. The selected articles are categorized by the following: articles distribution based on the year of publication, publication database, various journals, contribution of authors, continent, scale of industry, implemented approaches, focused industry, tools and techniques used in phases of Six Sigma methodology, and performance indicators used in Six Sigma implementation. Then after, future scopes of research opportunities are derived based on significant findings.

The literature revealed that: Very few work was undertaken on the implementation of Six Sigma in various manufacturing industries like ceramic, paper, gems and jewelry, cement, furniture, stone, fertilizer, forging, paper and surface treatment industries. Most of the researchers have considered very few performance indicators to identify the improvement after Six Sigma implementation. But, there is no clue regarding overall improvement in different perspectives after the implementation of Six Sigma. The financial indicators, personnel indicators, process indicators and customer indicators are useful to measure the overall improvement after the implementation of Six Sigma in the manufacturing sector.

The study was carried out on the implementation of Six Sigma methodology in various manufacturing industries, and various performance indicators were identified while implementing the Six Sigma methodology. Case studies pertaining to service industries were not covered here.

Very little research has been carried out to measure the overall success of implementing Six Sigma methodology in manufacturing industries. This paper will provide value to students, researchers and practitioners of Six Sigma by providing insight into the implementation of Six Sigma in manufacturing industries.

Additive manufacturing requires a systemic approach to help industry on technology applicability research. Towards this end, the purpose of this research is to help manufacturing business leaders decide whether digitalised manufacturing based on additive manufacturing are suitable for engineering applications and help them plan technology transfer decisions.

The methodology is based on case study research and action research, involving a mix of quantitative and qualitative research methods. The empirical part involved the study of the fatigue life of industrial component manufactured by laser sintering as well as a combination of quantitative and qualitative methods to define a strategic decision-making.

Laser-sintered plastic materials are suitable in end use automotive applications, especially when there are multiple product variations. Fatigue life of the tested coupling meets the design requirements. Additionally, production of mechanical parts can be substituted by additive methods while digitalising the manufacturing process to gain productivity, especially when there is a need for mass-customisation.

This research relies on a single case study research. The application used is unique and its technical empirical data cannot be transferred directly to other applications.

Industry practitioners can use this research to shed light on technology transferability challenges considering technical feasibility of additive polymer materials, economic aspects as well as strategic implications for implementing digitalised manufacturing methods based on additive manufacturing.

This research presents a combined study of technical and strategic factors for additive manufacturing transferability using an industrial mass-customisation case as an example. In addition, a new cost comparison model is presented including the impact of geometry variations.

The purpose of this paper is to study the influence of dimple textures on the friction and wear properties of tapered roller bearings (TRBs) with many pattern parameters, e.g. diameter, depth and area density under starved lubrication.

The pattern parameters include the dimple diameter (D; 60, 100 and 200 µm), dimple depth (H; 5, 10 and 20 µm) and area density (S; 6%, 12% and 24%). Dimples were fabricated on the outer ring (OR) of TRBs using a laser marking machine. The tribological properties of dimple-textured TRBs under starved lubrication were studied on a vertical universal friction wear tester with special friction pairs. The effect mechanisms of dimple textures on the tribological properties of TRBs are presented and summarized through experiments and discussions.

When dimple-textured TRBs revolve under starved lubrication, the average coefficients of friction (ACOF) and wear losses are markedly lower than those of non-textured bearings. S has the greatest influence on the COF curve. When D is 100 µm and S is 24%, the ACOF and wear losses are both lowest, i.e. 0.00426 and 0.51 mg, respectively. Under the same test conditions, compared with the non-textured group, its COF and wear loss decreased by 35.6% and 62.5%, respectively.

This work provides a useful reference for the research on the raceways of textured TRBs.

This paper aims to exploit an orthogonal space-time block code (OSTBC) and maximal ratio combining (MRC) techniques to evaluate error rate performance of multiple-input multiple-output system for different modulation schemes operating over single- and double-Weibull fading channels.

The authors provided a novel analytical expression for cumulative distribution function (CDF) of double-Weibull distribution in the form of Meijer-G function. They also evaluated probability density function (PDF) and CDF for single- and double-Weibull random variables. CDF-based closed-form expressions of symbol error rate (SER) are computed for the proposed systems’ design.

Based on simulation and analytical results, the authors have shown that double-Weibull fading which shows the cascaded nature of channel gives significantly poor SER performance compared to that of single-Weibull fading. Moreover, MRC offers an improved error rate performance compared to that of OSTBC. As the fading parameter increases for any modulation technique, the required signal-to-noise ratio (SNR) gap between single- and double-Weibull fading decreases. Finally, it is observed that the analytical results are a good approximation to simulation results.

For practical implication, the authors use a number of antennas at the base station, but solely to maximize performance, one can use receive diversity, i.e. MRC.

Using higher-order modulation (i.e. 16-QAM), 4 and 1 dB less SNR is required at high and less fading, respectively, in single-Weibull fading as compared to double-Weibull fading. Hence, at higher-order modulation, double-Weibull channel model performs better as compared to lower-order modulation.

Frugal innovation focuses on the core functionalities with the highest stakeholder benefits and directly targets user requirements. It has been widely adopted in developing countries, and extensively researched from both consumer and sustainable perspectives. However, few studies on frugal innovation consider “quality”, a seminal business management concept. This study focuses on this gap and uses a quality lens to understand frugal innovation.

This study adopts a mixed methodology. The Delphi focus group method is first applied to identify two cases of frugal innovation in the construction industry and a cross-case analysis done. Then, the analytic hierarchy process (AHP) is used to examine eight product quality dimensions to draw the final conclusions.

From Garvin’s concept of quality, frugal innovation focuses on performance and conformance. Furthermore, it prioritises a value-based approach the most.

This study examines frugal innovation from quality perspective. This opens up a new line of research which contributes to both streams. The study is based on construction which is a limitation of the study.

A quality-based frugal innovation understanding can be helpful in the conceptualisation, implementation and acceptance of the frugal innovation business model. It can provide clarity on the innovation's value proposition and also help in operationalisation of the business model.

Frugal encourages social entrepreneurs and understanding of the concept from quality perspective shall facilitate the operationalisation will become easier for them.

To the author’s knowledge, this is the first study at the interface of frugal innovation and quality management. Furthermore, the use of AHP to prioritise equality approaches and dimensions is an original contribution.