J. Paulo Davim and Francisco Mata
Surface roughness, normally defined by the Ra and Rt/Rmax parameters, is an important topic in the manufacturing engineering, for controlling produced components. This paper…
Abstract
Surface roughness, normally defined by the Ra and Rt/Rmax parameters, is an important topic in the manufacturing engineering, for controlling produced components. This paper presents a study of the influence of cutting parameters on surface roughness in turning of glass‐fibre‐reinforced plastics (GFRPs). A plan of experiments was performed on controlled machining with cutting parameters prefixed in workpiece. A statistical technique, using orthogonal arrays and analysis of variance, has been employed to investigate the influence of cutting parameters on surface roughness in turning GFRPs tubes using polycrystalline diamond cutting tools. The objective was to obtain the contribution percentages of the cutting parameters (cutting velocity and feed rate) on the surface roughness in GFRPs workpiece.
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The purpose of this paper is to combine notions from the POST Model of Economic Geography and Learning Theory from International Business to study how firms may enhance their…
Abstract
Purpose
The purpose of this paper is to combine notions from the POST Model of Economic Geography and Learning Theory from International Business to study how firms may enhance their responsiveness to institutional processes and changes through different forms of international learning. Focussing on one form of institutional changes, namely pro-market reforms, the paper analyzes how firms may boost the potential benefits from such changes through international strategies that increase their access to knowledge spillovers and absorptive capacity. These strategies include international product diversification, enhancing innovation capabilities, informal institutional exposure, accumulated internationalization knowledge, and overall experiential knowledge.
Design/methodology/approach
The hypotheses are tested using generalized least squares models with AR(1) panel-specific autocorrelation and heteroskedasticity correction. Based on the preliminary analyses performed in these studies, the author also executes a Hausman test, Bartlett’s test, and James/Alexander’s test. The results of these analyses indicate that the use of random effects is appropriate; that moderating effects are present; and that multivariate analyses using these moderators are suitable, respectively.
Findings
The results indicate that pro-market reforms have a positive and significant effect on the profitability of firms from developing countries. Furthermore, they provide support for the positive moderating effects of international product diversification, innovation capabilities, informal institutional exposure, accumulated internationalization knowledge, and overall experiential knowledge. Together, these findings suggest that through their international strategic decisions, MNEs can enhance their access to knowledge and become more responsive to institutional changes in their home market.
Research limitations/implications
This paper contributes to the economic geography literature by linking the POST Model with the classification of types of knowledge from Learning Theory. The paper analyzes how characteristics of place, organization, space, and time play a different role for each of the three basic types of knowledge that is relevant for international firms: institutional, business, and internationalization. Furthermore, the paper contributes to the literature on reforms and firm profitability by delving deeper into the moderating effect of strategic decisions on the relationship between reforms and firm performance. This allows us to have a deeper comprehension of how various sources of international learning may enhance the responsiveness of firms to institutional changes.
Originality/value
The paper provides several important contributions to the international strategy literature. First, it contributes to Learning Theory by combining it with the POST Model of Economic Geography to study how each of the three sources of knowledge (and their subcomponents) can be further broken down into factors of place, organization, space, and time. Second, it contributes to the literature of institutional change by studying how knowledge acquired through vastly different means can provide firms with sources of competitive advantage over other local competitors when responding to institutional changes in their home market. Third, it contributes to the literature on reforms and profitability by studying five novel moderators of this relationship.
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Vitor Augusto Martins da Costa and Danielle Carvalho Ribeiro
This paper aims to answer the following question: Is PPP a financially viable alternative for the management of regional airports in Brazil?
Abstract
Purpose
This paper aims to answer the following question: Is PPP a financially viable alternative for the management of regional airports in Brazil?
Design/methodology/approach
The methodology is based on the case study of the innovative model of Zona da Mata Regional Airport management. It was used Value for Money as a method to compare this case with the conventional airport management alternative.
Findings
It was observed that, when compared to the airport management alternative through contracting third parties, the public–private partnership (PPP) provided a reduction of almost 70% of public spending on the management of this infrastructure. Besides the financial advantage, other benefits of this PPP contract were also observed.
Research limitations/implications
The analyses carried out in this study are not exhaustive and can be improved and remade as the life cycle of the PPP contract studied is progressed.
Practical implications
It was concluded, from the results found, that PPP is an efficient alternative for the management of regional airports in Brazil, and the model can be replicated for similar airports.
Originality/value
When analyzing the results of this innovative project of managing a regional airport through a PPP, this work made it possible to measure the positive impacts of this alternative and demonstrate the potential of the PPP as an alternative for the management of other regional airports in Brazil.
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Vitor da Mata Quintella, Antônio Francisco de Almeida da Silva Jr, Jose Ricardo Uchoa Cavalcanti Almeida and Marcelo Embiruçu
The purpose of this paper is to identify, measure and optimise financial risk and its effect on returns from innovation projects on an accrual basis and on a cash basis in a…
Abstract
Purpose
The purpose of this paper is to identify, measure and optimise financial risk and its effect on returns from innovation projects on an accrual basis and on a cash basis in a commodity industry.
Design/methodology/approach
A hypothetical case study, based on a real case, of a petrochemical commodity industry in Brazil was analysed with commodities pricing rules based on actual contracts. Earnings at risk (EaR) and cash flow at risk (CFaR) measures were applied, as well as a metric proposed in this paper called cash balance at risk (CBaR).
Findings
The paper demonstrates that financial risk measurement and optimisation are important issues in the decision-making process in the petrochemical industry. EaR, CFaR and CBaR measures are helpful when used alongside standard procedures of project evaluation. The findings also show that innovative technologies, in certain conditions, may act as “natural hedging”. It was found that the time delay between revenues and expenses leads to financial risk exposure to changes in prices and foreign exchange rates. Projects can use financing and hedging to boost their results.
Originality/value
An innovative project was compared with an expansion project in a petrochemical industry. A model for petrochemical commodities contract pricing was added in an analysis that included financing and hedging. The findings in this paper suggest that it is important to consider financial risk measures in project evaluation.
Objetivo
O objetivo deste trabalho é identificar, medir e otimizar o risco financeiro e seus efeitos sobre os resultados de projetos com inovação, tanto na perspectiva do regime contábil quanto do regime de caixa, em uma indústria de commodities.
Abordagem
Um estudo de caso hipotético, baseado em um caso real de uma indústria petroquímica brasileira, foi analisado com regras de precificação de commodities baseados em contratos reais. As métricas Earnings at Risk (EaR) e Cash Flow at Risk (CFaR) foram utilizadas, assim como uma métrica proposta neste trabalho, denominada Cash Balance at Risk (CBaR).
Resultados
Este artigo demonstrou que a mensuração e otimização do risco financeiro são questões importantes no processo de tomada de decisão em uma indústria petroquímica. As medidas EaR, CFaR e CBaR se apresentaram como contribuições ao processo padrão de avaliação de projetos. Os resultados também demonstraram que inovações tecnológicas, em certas condições, podem funcionar como um “hedge natural”. Foi verificado que descasamentos temporais entre recebimentos e despesas geram uma exposição financeira a oscilações em preços e em valores de moedas estrangeiras. Financiamento e hedge podem ser utilizados em conjunto para aprimorar resultados de projetos.
Originalidade/valor
Um projeto com inovação foi comparado com um projeto de expansão em uma indústria petroquímica. Foi realizada uma analise de risco que agrega ao financiamento e ao hedge o uso de contratos de precificação de commodities. Os resultados desse projeto demonstram que é importante considerar medidas de risco financeiro nas avaliações de projetos.
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Jose Matas, Francisco Javier Llorens-Montes and Nieves Perez
The objective of this study is to examine how emotions play a role in the firm’s reaction to disruptions in the supply chain. Drawing on the upper echelons theory, we evaluate…
Abstract
Purpose
The objective of this study is to examine how emotions play a role in the firm’s reaction to disruptions in the supply chain. Drawing on the upper echelons theory, we evaluate whether managers’ perception of collective emotions (CEs) in the supply environment affects the execution of specific organisational responses (bridging and buffering) to disruptive events. Furthermore, we investigate to what extent companies' own capabilities, such as supply chain resilience, influence this relationship.
Design/methodology/approach
A web-based survey was distributed among managers involved in supply chain relationship management (e.g. supply chain or purchasing managers). LinkedIn was used to identify and contact adequate respondents, and 221 valid responses were collected. The proposed theoretical model was empirically tested using structural equation modelling based on partial least squares (PLS-SEM).
Findings
Results suggest that emotions can shape a firm's response to supply chain disruptions. In fact, managers are more likely to pursue both bridging and buffering strategies as their perception of CEs increases. However, the intensity and underlying motivations for pursuing each strategy differ.
Originality/value
When CEs are perceived by buyer managers, stronger supply chain resilience incentivises the choice of cooperative practices within existing suppliers, thereby reinforcing pre-existing links. We conclude that combining companies' inherent variables or capabilities with managerial cognition and perceptions can improve our understanding of decision-making processes and buyer–supplier relationships.
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Francisco Rubio, Fares J. Abu‐Dakka, Francisco Valero and Vicente Mata
The purpose of this paper is to compare the quality and efficiency of five methods for solving the path planning problem of industrial robots in complex environments.
Abstract
Purpose
The purpose of this paper is to compare the quality and efficiency of five methods for solving the path planning problem of industrial robots in complex environments.
Design/methodology/approach
In total, five methods are presented for solving the path planning problem and certain working parameters have been monitored using each method. These working parameters are the distance travelled by the robot and the computational time needed to find a solution. A comparison of results has been analyzed.
Findings
After this study, it could be easy to know which of the proposed methods is most suitable for application in each case, depending on the parameter the user wants to optimize. The findings have been summarized in the conclusion section.
Research limitations/implications
The five techniques which have been developed yield good results in general.
Practical implications
The algorithms introduced are able to solve the path planning problem for any industrial robot working with obstacles.
Social implications
The path planning algorithms help robots perform their tasks in a more efficient way because the path followed has been optimized and therefore they help human beings work together with the robots in order to obtain the best results from them.
Originality/value
The paper shows which algorithm offers the best results, depending on the example the user has to solve and the parameter to be optimized.
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Francisco Rubio, Francisco Valero, Joseph Sunyer and Vicente Mata
The purpose of this paper is to solve the path‐planning problem of industrial robots in complex environments.
Abstract
Purpose
The purpose of this paper is to solve the path‐planning problem of industrial robots in complex environments.
Design/methodology/approach
A direct method (in each step, the path is been recorded) is presented in which the search of the path is made in the state space of the robotic system, and it makes use of the information generated about the characteristics of the process, introducing graph techniques for branching. The method poses an optimization problem that aims at minimizing the distance travelled by the significant points of the robot.
Findings
A new approach to solve the path‐planning problem has been introduced in which the behaviour of three operational parameters (computational time, distance travelled and number of configurations generated) have been analyzed so that the user can choose the most efficient algorithm depending on which parameter he is most interested in.
Research limitations/implications
A new technique has been introduced which yields good results as the examples show.
Practical implications
The algorithm is able to obtain the solution to the path‐planning problem for any industrial robot working in a complex environment.
Originality/value
Gives a new tool for solving the path‐planning problem.
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Nuria Rosillo, Angel Valera, Francesc Benimeli, Vicente Mata and Francisco Valero
The purpose of this paper is to present the development and validation of a methodology which allows modeling and solving the inverse and direct dynamic problem in real time in…
Abstract
Purpose
The purpose of this paper is to present the development and validation of a methodology which allows modeling and solving the inverse and direct dynamic problem in real time in robot manipulators.
Design/methodology/approach
The robot dynamic equation is based on the Gibbs‐Appell equation of motion, yielding a well‐structured set of equations that can be computed in real time. This paper deals with the implementation and calculation of the inverse and direct dynamic problem in robots, with an application to the real‐time control of a PUMA 560 industrial robot provided with an open control architecture based on an industrial personal computer.
Findings
The experimental results show the validity of the dynamic model and that the proposed resolution method for the dynamic problem in real time is suitable for control purposes.
Research limitations/implications
The accuracy of the applied friction model determines the accuracy of the identified overall model and consequently of the control. This is especially obvious in the case of the PUMA 560 robot, in which the presence of friction is remarkable in some of their joints. Hence, future work should focus on identifying a more precise friction model. The robot model could also be extended by incorporating rotor dynamics and could be applied for different robot configurations as parallel robots.
Originality/value
Gibbs‐Appell equations are used in order to develop the robotic manipulator dynamic model, instead of more usual dynamics formulations, due to several advantages that these exhibit. The obtained non‐physical identified parameters are adapted in order to enable their use in a control algorithm.