International Journal of Production Research, 2019
Most shops in practice are constrained by more than one resource. Consequently, a large body of l... more Most shops in practice are constrained by more than one resource. Consequently, a large body of literature on dual resource constrained shops has emerged. This research typically focuses on worker assignment rules, with attention being on when and where to move workers. In contrast, the decision concerning who to reallocate to a station has received limited attention. The limited prior work assumes workers are assigned to a new station as soon as they become available or seeks to minimize the risk of worker idleness. Using simulation, we question this assumption and show that it can be beneficial to introduce additional worker idleness to ensure workers only work at their most efficient station(s). In general, it is less likely that there are several workers available for one station than it is for there to be multiple stations available for one worker. Consequently, the Who Rule is used less frequently than the Where rule and has less of an impact on performance. Finally, considering the criticality of work orders as part of the Where Rule is important in assembly shops; but if labor is heterogeneous then the focus should be on efficiency. The findings have important implications for research and practice.
The present paper presents the conceptual mechanical design of a Standing Frame for children with... more The present paper presents the conceptual mechanical design of a Standing Frame for children with mental deficiency. Those children deal with great difficulties in maintaining a correct biped posture, hindering certain system organs to work in its fullness. Thus, the target goal of this project is to provide a correct biped posture to the child with mental deficiency. To achieve this goal there were defined the main goals that the standing frame should fulfil: safety, comfort, adaptability, attractiveness and accessibility. After the definition of certain functions and specifications the final solution comes up. For this solution it was selected metallic materials (structure of the Standing Frame) and polymeric materials (supports). It was also needed to select a lifting system, to lift the child from the seat to the biped position. The best solution found was an hydraulic, linear and single acting actuator. In order to ecologically guide the project it was chosen materials with fabrication and recycling processes that allow the final solution to be the most ecologic as possible.
Integration of process planning and scheduling—A modified genetic algorithm-based approach
Computers & Operations Research, 2009
Traditionally, process planning and scheduling for parts were carried out in a sequential way, wh... more Traditionally, process planning and scheduling for parts were carried out in a sequential way, where scheduling was done after process plans had been generated. Considering the fact that the two functions are usually complementary, it is necessary to integrate them more tightly so that performance of a manufacturing system can be improved greatly. In this paper, a new integration model
The industry 4.0 revolution provides the machines with a sensory and communicational capacity, wh... more The industry 4.0 revolution provides the machines with a sensory and communicational capacity, which allows them to monitor and collect large amounts of information. This kind of data have an impact on planning, maintenance, and management of production, enabling real time reaction, efficiency increase, and the development of predictive and process improvement models. The most recent machines are prepared to communicate with the existing monitoring systems, however, many (around 60%) do not. The objective of this work is to present the proposal of a system for remote monitoring of equipment in real time that meets the requirements of low cost, simplicity, and flexibility. The system monitors the equipment in a simple and agile way, regardless of its sophistication, installation constraints and company resources. A prototype of a system was developed and tested both laboratory conditions and a productive environment. The proposed architecture of the system comprises of a sensor that ...
The so-called fourth industrial revolution brought a disruptive change in the way that communicat... more The so-called fourth industrial revolution brought a disruptive change in the way that communication technologies, distributed systems, intelligent data management, analytics and computational capability and other technologies are integrated to enable new functions and enhance capabilities not only to production systems, but also in many other domains such as education. Mobile Health (m-Health) education is one of these, where the number of applications and tools for m-Health education is extensive. The SARS-Cov2 (Covid-19) pandemic brought to life immense challenges towards education, technology, and the symbiosis with medicine. This paper introduces 31 of the current state-of-the-art m-Health education applications and analyses the results of an an inquiry to students and junior doctors during the confinement, designed to understanding their knowledge, use and trust regarding these apps. The results show that several applications are well perceived by their users and deserved thei...
To remain competitive, companies must continuously improve the processes at hand, be they adminis... more To remain competitive, companies must continuously improve the processes at hand, be they administrative, production, or logistics. The objective of the study described in this paper was to develop a decision-making tool based on a simulation model to support the production of knits and damask fabrics. The tool was used to test different control strategies for material flow, from the raw material warehouse to the finished product warehouse, and thus can also be used to evaluate the impacts of these strategies on the productivity. The data upon which the decision support tool was built were collected from five sectors of the plant: the raw material warehouse, knit production, damask production, finishing work, and the finished product warehouse. The decision support tool met the objectives of the project, with all five strategies developed showing positive results. Knit and damask production rates increased by up to 8% and 44%, respectively, and a reduction of 75% was observed in the...
In this work, a survey is made of the analysis of the resource selection process. We approach the... more In this work, a survey is made of the analysis of the resource selection process. We approach the process also from the point of view of conventional enterprises but with particular emphasis on the existent models in Agile/Virtual Enterprises in order to identify the main limitations and shortcomings of the process. This analysis was focused in the global process of the resource selection, namely in terms of the pre-selection and selection phases, requisites, mathematical models, tools and other relevant areas in the existent models. It is concluded that the resource pre-selection is an area that is not adequately explored in a systematic way. The value concept is not incorporated in the selection process. As a result, a reasoned analysis is not performed of the decision-making process for creating an Agile/Virtual Enterprise. These conclusions were made to envision a future approach that allows the incorporation of new areas that contribute to the improvement of the resource select...
The phenomenon of the enterprise organizational reconfiguration and its dynamics as a business al... more The phenomenon of the enterprise organizational reconfiguration and its dynamics as a business alignment enabler is discussed. Business alignment means the enterprise's actions undertaken to gain synergy between the business; that is, the market opportunity and the provision of the required, or innovative, product, with the required, or designed, specifications at the required, or proper, time, with the lowest cost and best possible return (financial or other). The enterprise's organization "fast reconfiguration," either as a proactive or as a reactive action, or "fast adaptation" or "flexibility" (as a "reactive" action), is seen as the main enabler of business alignment and the main requirement for achieving competitiveness. The need to keep a close alignment with the dynamic market environment in permanent change implies the high dynamics of the organizations' organization, or organizational structure, reconfiguration. The first part of the text presents enterprise's requirements for competitiveness and business alignment, while the second part discusses the phenomenon of the enterprise reconfigurability as the business alignment enabler. In the third part, an analysis of some organizational and management approaches, from the reconfigurability point of view, is presented. The text ends with a conclusion and references.
The implementation of the virtual enterprise (VE) model requires an agent, called a broker, who u... more The implementation of the virtual enterprise (VE) model requires an agent, called a broker, who undertakes several functions and whose increased performance contributes to the searched agility of this organisational model. From the set of functions that the broker can provide to the VE, there are some that may explicitly contribute to the process of VE integration. One of the processes that contributes to VE integration, either in the project phase, during the resources system configuration, or in the operation phase, when the system reconfiguration is required, is the resources system selection process. We will approach, in this work, the importance of the broker in the resources system selection through the comparison of his performance in that process to the performance expected of the VE itself, if the person for whom it is responsible (or principal) performs the same process. This comparison is made based on the simulation results obtained from a numeric demonstrator specifical...
In the last few years, the industrial, scientific, and technological fields have been subject to ... more In the last few years, the industrial, scientific, and technological fields have been subject to a revolutionary process of digitalization and automation called Industry 4.0. Its implementation has been successful mainly in the economic field of sustainability, while the environmental field has been gaining more attention from researchers recently. However, the social scope of Industry 4.0 is still somewhat neglected by researchers and organizations. This research aimed to study Industry 4.0 and sustainability themes using data science, by incorporating open data and open-source tools to achieve sustainable Industry 4.0. To that end, a quantitative analysis based on open data was developed using open-source software in order to study Industry 4.0 and sustainability trends. The main results show that manufacturing is a relevant value-added activity in the worldwide economy; that, foreseeing the importance of Industry 4.0, countries in America, Asia, Europe, and Oceania are incorporat...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
International Journal of Production Research, 2019
Most shops in practice are constrained by more than one resource. Consequently, a large body of l... more Most shops in practice are constrained by more than one resource. Consequently, a large body of literature on dual resource constrained shops has emerged. This research typically focuses on worker assignment rules, with attention being on when and where to move workers. In contrast, the decision concerning who to reallocate to a station has received limited attention. The limited prior work assumes workers are assigned to a new station as soon as they become available or seeks to minimize the risk of worker idleness. Using simulation, we question this assumption and show that it can be beneficial to introduce additional worker idleness to ensure workers only work at their most efficient station(s). In general, it is less likely that there are several workers available for one station than it is for there to be multiple stations available for one worker. Consequently, the Who Rule is used less frequently than the Where rule and has less of an impact on performance. Finally, considering the criticality of work orders as part of the Where Rule is important in assembly shops; but if labor is heterogeneous then the focus should be on efficiency. The findings have important implications for research and practice.
The present paper presents the conceptual mechanical design of a Standing Frame for children with... more The present paper presents the conceptual mechanical design of a Standing Frame for children with mental deficiency. Those children deal with great difficulties in maintaining a correct biped posture, hindering certain system organs to work in its fullness. Thus, the target goal of this project is to provide a correct biped posture to the child with mental deficiency. To achieve this goal there were defined the main goals that the standing frame should fulfil: safety, comfort, adaptability, attractiveness and accessibility. After the definition of certain functions and specifications the final solution comes up. For this solution it was selected metallic materials (structure of the Standing Frame) and polymeric materials (supports). It was also needed to select a lifting system, to lift the child from the seat to the biped position. The best solution found was an hydraulic, linear and single acting actuator. In order to ecologically guide the project it was chosen materials with fabrication and recycling processes that allow the final solution to be the most ecologic as possible.
Integration of process planning and scheduling—A modified genetic algorithm-based approach
Computers & Operations Research, 2009
Traditionally, process planning and scheduling for parts were carried out in a sequential way, wh... more Traditionally, process planning and scheduling for parts were carried out in a sequential way, where scheduling was done after process plans had been generated. Considering the fact that the two functions are usually complementary, it is necessary to integrate them more tightly so that performance of a manufacturing system can be improved greatly. In this paper, a new integration model
The industry 4.0 revolution provides the machines with a sensory and communicational capacity, wh... more The industry 4.0 revolution provides the machines with a sensory and communicational capacity, which allows them to monitor and collect large amounts of information. This kind of data have an impact on planning, maintenance, and management of production, enabling real time reaction, efficiency increase, and the development of predictive and process improvement models. The most recent machines are prepared to communicate with the existing monitoring systems, however, many (around 60%) do not. The objective of this work is to present the proposal of a system for remote monitoring of equipment in real time that meets the requirements of low cost, simplicity, and flexibility. The system monitors the equipment in a simple and agile way, regardless of its sophistication, installation constraints and company resources. A prototype of a system was developed and tested both laboratory conditions and a productive environment. The proposed architecture of the system comprises of a sensor that ...
The so-called fourth industrial revolution brought a disruptive change in the way that communicat... more The so-called fourth industrial revolution brought a disruptive change in the way that communication technologies, distributed systems, intelligent data management, analytics and computational capability and other technologies are integrated to enable new functions and enhance capabilities not only to production systems, but also in many other domains such as education. Mobile Health (m-Health) education is one of these, where the number of applications and tools for m-Health education is extensive. The SARS-Cov2 (Covid-19) pandemic brought to life immense challenges towards education, technology, and the symbiosis with medicine. This paper introduces 31 of the current state-of-the-art m-Health education applications and analyses the results of an an inquiry to students and junior doctors during the confinement, designed to understanding their knowledge, use and trust regarding these apps. The results show that several applications are well perceived by their users and deserved thei...
To remain competitive, companies must continuously improve the processes at hand, be they adminis... more To remain competitive, companies must continuously improve the processes at hand, be they administrative, production, or logistics. The objective of the study described in this paper was to develop a decision-making tool based on a simulation model to support the production of knits and damask fabrics. The tool was used to test different control strategies for material flow, from the raw material warehouse to the finished product warehouse, and thus can also be used to evaluate the impacts of these strategies on the productivity. The data upon which the decision support tool was built were collected from five sectors of the plant: the raw material warehouse, knit production, damask production, finishing work, and the finished product warehouse. The decision support tool met the objectives of the project, with all five strategies developed showing positive results. Knit and damask production rates increased by up to 8% and 44%, respectively, and a reduction of 75% was observed in the...
In this work, a survey is made of the analysis of the resource selection process. We approach the... more In this work, a survey is made of the analysis of the resource selection process. We approach the process also from the point of view of conventional enterprises but with particular emphasis on the existent models in Agile/Virtual Enterprises in order to identify the main limitations and shortcomings of the process. This analysis was focused in the global process of the resource selection, namely in terms of the pre-selection and selection phases, requisites, mathematical models, tools and other relevant areas in the existent models. It is concluded that the resource pre-selection is an area that is not adequately explored in a systematic way. The value concept is not incorporated in the selection process. As a result, a reasoned analysis is not performed of the decision-making process for creating an Agile/Virtual Enterprise. These conclusions were made to envision a future approach that allows the incorporation of new areas that contribute to the improvement of the resource select...
The phenomenon of the enterprise organizational reconfiguration and its dynamics as a business al... more The phenomenon of the enterprise organizational reconfiguration and its dynamics as a business alignment enabler is discussed. Business alignment means the enterprise's actions undertaken to gain synergy between the business; that is, the market opportunity and the provision of the required, or innovative, product, with the required, or designed, specifications at the required, or proper, time, with the lowest cost and best possible return (financial or other). The enterprise's organization "fast reconfiguration," either as a proactive or as a reactive action, or "fast adaptation" or "flexibility" (as a "reactive" action), is seen as the main enabler of business alignment and the main requirement for achieving competitiveness. The need to keep a close alignment with the dynamic market environment in permanent change implies the high dynamics of the organizations' organization, or organizational structure, reconfiguration. The first part of the text presents enterprise's requirements for competitiveness and business alignment, while the second part discusses the phenomenon of the enterprise reconfigurability as the business alignment enabler. In the third part, an analysis of some organizational and management approaches, from the reconfigurability point of view, is presented. The text ends with a conclusion and references.
The implementation of the virtual enterprise (VE) model requires an agent, called a broker, who u... more The implementation of the virtual enterprise (VE) model requires an agent, called a broker, who undertakes several functions and whose increased performance contributes to the searched agility of this organisational model. From the set of functions that the broker can provide to the VE, there are some that may explicitly contribute to the process of VE integration. One of the processes that contributes to VE integration, either in the project phase, during the resources system configuration, or in the operation phase, when the system reconfiguration is required, is the resources system selection process. We will approach, in this work, the importance of the broker in the resources system selection through the comparison of his performance in that process to the performance expected of the VE itself, if the person for whom it is responsible (or principal) performs the same process. This comparison is made based on the simulation results obtained from a numeric demonstrator specifical...
In the last few years, the industrial, scientific, and technological fields have been subject to ... more In the last few years, the industrial, scientific, and technological fields have been subject to a revolutionary process of digitalization and automation called Industry 4.0. Its implementation has been successful mainly in the economic field of sustainability, while the environmental field has been gaining more attention from researchers recently. However, the social scope of Industry 4.0 is still somewhat neglected by researchers and organizations. This research aimed to study Industry 4.0 and sustainability themes using data science, by incorporating open data and open-source tools to achieve sustainable Industry 4.0. To that end, a quantitative analysis based on open data was developed using open-source software in order to study Industry 4.0 and sustainability trends. The main results show that manufacturing is a relevant value-added activity in the worldwide economy; that, foreseeing the importance of Industry 4.0, countries in America, Asia, Europe, and Oceania are incorporat...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
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