Build-Up an Economical Tool for Machining Operations Cost Estimation

Currently, there is a lack of affordable and simple tools for the estimation of these costs, especially for machining operations. This is particularly true for manufacturing SMEs, in which the cost estimation of machined parts is usually performed based only on required material for part production, or involves a time-consuming, non-standardized technical analysis. Therefore, a cost estimation tool was developed, based on the calculated machining times and amount of required material, based on the final drawing of the requested workpiece. The tool was developed primarily for milling machines, considering milling, drilling, and boring/threading operations. Regarding the considered materials, these were primarily aluminum alloys. However, some polymer materials were also considered. The tool first estimates the required time for total part production and then calculates the total cost. The total production time is estimated based on the required machining operations, as well as drawing, programming, and machine setup time. A part complexity level was also introduced, based on the number of details and operations required for each workpiece, which will inflate the estimated times. The estimation tool was tested in a company setting, comparing the estimated operation time values with the real ones, for a wide variety of parts of differing complexity. An average error of 14% for machining operation times was registered, which is quite satisfactory, as this time is the most impactful in terms of machining cost. However, there are still some problems regarding the accuracy in estimating finishing operation timesinfo:eu-repo/semantics/publishedVersio

Developing a Novel Fully Automated Concept to Produce Bowden Cables for the Automotive Industry

The automotive industry is one of the driving forces of the global industry; thus, it is a very competitive sector which creates a constant need for process improvement, regarding productivity, quality, and flexibility. Automation has proven to be a viable solution for these production problems, with the rising adoption of these automated system by companies that try to design and implement more flexible systems, while reducing costs and improving process quality. Furthermore, the use of automation reduces the manpower factor and its associated variability. In the present work, a new concept for a Bowden cable production process is presented by employing the design science research (DSR) methodology. The project starts with the analysis of the previous production concept, determining possible problems and improvements, as well as setting objectives/requirements for a possible new concept/equipment. This information was used to develop a new automated Bowden cable production equipment, implementing several changes to the old concept and filling a gap in the literature in this field. The developed system was implemented and tested. A considerable reduction in cycle time was registered by 25%, which resulted in an increase of 30% in process productivityinfo:eu-repo/semantics/publishedVersio

Using an Artificial Neural Network Approach to Predict Machining Time

One of the most critical factors in producing plastic injection molds is the cost estimation of machining services, which significantly affects the final mold price. These services’ costs are determined according to the machining time, which is usually a long and expensive operation. If it is considered that the injection mold parts are all different, it can be understood that the correct and quick estimation of machining times is of great importance for a company’s success. This article presents a proposal to apply artificial neural networks in machining time estimation for standard injection mold parts. For this purpose, a large set of parts was considered to shape the artificial intelligence model, and machining times were calculated to collect enough data for training the neural networks. The influences of the network architecture, input data, and the variables used in the network’s training were studied to find the neural network with greatest prediction accuracy. The application of neural networks in this work proved to be a quick and efficient way to predict cutting times with a percent error of 2.52% in the best case. The present work can strongly contribute to the research in this and similar sectors, as recent research does not usually focus on the direct prediction of machining times relating to overall production cost. This tool can be used in a quick and efficient manner to obtain information on the total machining cost of mold parts, with the possibility of being applied to other industry sectorsinfo:eu-repo/semantics/publishedVersio

A Novel Robotic Manipulator Concept for Managing the Winding and Extraction of Yarn Coils

Wire rope manufacturing is an old industry that maintains its place in the market due to the need for products with specific characteristics in different sectors. The necessity for modernization and performance improvement in this industry, where there is still a high amount of labor dedicated to internal logistics operations, led to the development of a new technology method, to overcome uncertainties related to human behaviour and fatigue. The removal of successive yarn coils from a twisting and winding machine, as well as cutting the yarn and connecting the other end to the shaft in order to proceed with the process, constitutes the main problem. As such, a mobile automatic system was created for this process, due to its automation potential, with a project considering the design of a 3D model. This novel robotic manipulator increased the useful production time and decreased the winding coil removal cycle time, resulting in a more competitive, fully automated product with the same quality. This system has led to better productivity and reliability of the manufacturing process, eliminating manual labor and its cost, as in previously developed works in other industriesThe authors want to thank Jorge Seabra and Carlos Fernandes from CETRIB/INEGI/LAETA due their continuous support.info:eu-repo/semantics/publishedVersio

Community viral load of HIV in Brazil, 2007 - 2011 : potential impact of highly active antiretroviral therapy (HAART) in reducing new infections

Objetivo: estimar o volume de vírus circulante de HIV na população brasileira e avaliar o potencial impacto da terapia antirretroviral (HAART) na redução de novas infecções, com o propósito de construir evidências e informações para subsidiar a implementação de políticas de saúde. Métodos : Ferramentas de análise espacial foram utilizadas para descrever os padrões existentes na densidade da carga viral utilizando o método Kernel quártico. As informações da carga viral e tratamento são oriundas da base conjunta do Sistema de Controle de Exames Laboratoriais (Siscel), com informações do histórico da carga viral do indivíduo e do Sistema de Controle Logístico de Medicamentos (Siclom), que controla a dispensa dos medicamentos para a terapia antirretroviral. Resultados: Observou-se que a carga viral comunitária (CVC) apresentou redução progressiva no período de 2007 a 2011, acompanhada de uma redução da carga viral média (CVCM) superior a 32% (22.900 cópias/mL em 2007 versus 15.418 cópias/mL em 2011). Nesse período, houve redução da CVCM em todas as grandes regiões do Brasil, embora o Norte e Nordeste tenham apresentado, respectivamente, CVCM 1,7 e 1,5 vezes a registrada no Sudeste. Em uma comparação entre os indivíduos que faziam ou não uso da HAART, observou-se aumento persistente da carga viral naqueles que não faziam uso da terapia de até 3,9 vezes em 2011. Conclusão: A abordagem apresentada neste estudo aponta a existência de aglomerados no espaço com altas concentrações. O uso do Kernel na identificação de aglomerados no espaço mostrou-se um bom instrumento para análise exploratória, possibilitando a visualização do risco em determinadas áreas geográficas sem as usuais divisões político-administrativas.Objectives: to estimate the human immunodeficiency virus (HIV) viral load in the Brazilian population and to assess the potential impact of highly active antiretroviral therapy (HAART) in reducing new infections to build evidences and to gather information to support health policies. Methods: Spatial analysis and modeling tools were used to describe the existing patterns of the viral load density, using the Kernel method. Data on viral load and treatment were retrieved from the databases Laboratory Tests Control System (SISCEL), which contains information on the individual's history of viral load, and Medication Logistics Control System (SICLOM), which controls the dispensing of drugs used for antiretroviral therapy. Results: It was observed that the community viral load (CVL) decreased progressively from 2007 to 2011, accompanied by a decrease of more than 32% in the mean CVL (CVLM) - 22,900 copies/mL in 2007 versus 15,418 copies/mL in 2011. During this period, there was a reduction of CVLM in all regions of Brazil, although North and Northeast showed, respectively, CVLM 1.7 and 1.5 times higher than that in the Southeast region. A comparison between the individuals who underwent and who did not undergo HAART showed an increase of up to 3.9 times in 2011 in the viral load among those who did not undergo the therapy. Conclusion: The approach presented in this study indicates the existence of clusters with high concentrations. The use of Kernel in the identification of clusters proved to be a good tool for exploratory analysis, enabling the risk identification in certain geographic areas without the usual political and administrative divisions

Increasing the Sustainability of Manufacturing Processes in Plastic Injection: Recovering Out-Of-Service Robots to Eliminate Manual Assembly Operations

In the 20th century, there was a burst concerning the development of the automobile industry, which has become an essential asset for society. With its evolution, this industry created a foundation that based its competitiveness on satisfying people’s needs with the highest possible quality and always respecting the delivery deadlines. With the growth in demand, the improvement of certain processes was needed to achieve the desired production goals, accomplished through automation and robotics, as production and assembly lines increasingly used fully automated processes. In plastic injection lines, production is constant and carried out quickly, so it is desirable to perform component assembly steps that immediately support the output of the injection mould parts. This work consists of adapting an obsolete robotic cell to be implemented in one of the production lines to insert components into the injected parts, replacing labour work. Through a mechanical project and an automation design, the equipment was concluded and is currently in production, fulfilling the necessary requirements and improving the process’ cycle time. This proves that it is possible to recover old equipment, which is able to improve current tasks and common needs in modern industry, increasing the economic sustainability of the processes and saving resourcesinfo:eu-repo/semantics/publishedVersio

QUALIDADE DE VIDA DOS ACADÊMICOS DE ENFERMAGEM DA UNIVERSIDADE ESTADUAL DE RORAIMA

A Qualidade de Vida (QV) é o reflexo da percepção do indivíduo quanto aos aspectos físico, psíquico e social de sua vida, variando de forma positiva ou negativa a depender do contexto em que esteja inserido. Assim, este estudo objetivou identificar o nível de Qualidade de Vida do discente de enfermagem da Universidade Estadual de Roraima. Trata-se de uma pesquisa descritiva, transversal e de abordagem quantitativa com 55 acadêmicos do curso superior de enfermagem. A coleta dos dados ocorreu entre os meses de novembro de 2022 e abril de 2023. Aplicou-se questionário para caracterização dos dados sociodemográficos, acadêmicos, sono, atividade física e alimentação. A percepção da Qualidade de Vida foi avaliada por meio do instrumento WHOQOL-Bref. Os dados foram tabulados em planilhas do Excel 2020 e analisados a partir do software JAMOVI®. Os resultados preliminares indicam que a média de idade dos discentes foi de 22,6 anos (dp=2,6), prevalecendo os indivíduos do gênero feminino, cor parda, solteiro, sem filhos, residindo na capital, carro como principal meio de transporte, morando com os pais, sem atividade laboral, satisfeitos com o curso, mantendo atividade física regular, sem alimentação saudável e com média de sono de 6,7 horas (dp=1,4). Referente aos escores de QV, apenas o Domínio Físico se mostrou insatisfatório, e a média geral foi de 60,2. Apesar da Qualidade de Vida geral se mostrar satisfatória, alguns aspectos merecem evidência, como a qualidade da alimentação e do sono, fatores que estão repercutindo de forma negativa no Domínio Físico dos acadêmicos

Applying the SMED Methodology to Tire Calibration Procedures

Due to the automotive industry’s strict demands, customers submit constant production pressure, leading to the adoption of new methodologies, techniques, and management ideas. The goal is always to minimise losses and waste. These demands also affect the maintenance department, which has to keep the balance between machines’ availability for production and ensuring that the machines’ proper running conditions translate into excellent-quality products. Thus, continuous improvement and correct management of maintenance activities are crucial for a company to maintain effective production, without defects, breakdowns, and accidents. Nevertheless, some maintenance activities should also prevent the degradation of equipment conditions in order to produce high-quality products. This paper presents an improvement of maintenance activities conducted on equipment that produces large tires. The main problems and technical difficulties of Machine Tolerance Check (MTC) activities are explored by analysing existing documents, internal knowledge, and changes to working methods. We discuss the implementation of the SMED (Single-Minute Exchange of Die) methodology in calibration procedures, as this method is commonly applied to machines’ setups to reduce downtime. At the end of the study, a 31% decrease in the duration of machine tolerance check activities was achieved, which led to a significant increase in the equipment’s availabilityinfo:eu-repo/semantics/publishedVersio

Cutting Forces Assessment in CNC Machining Processes: A Critical Review

Machining processes remain an unavoidable technique in the production of high-precision parts. Tool behavior is of the utmost importance in machining productivity and costs. Tool performance can be assessed by the roughness left on the machined surfaces, as well as of the forces developed during the process. There are various techniques to determine these cutting forces, such as cutting force prediction or measurement, using dynamometers and other sensor systems. This technique has often been used by numerous researchers in this area. This paper aims to give a review of the different techniques and devices for measuring the forces developed for machining processes, allowing a quick perception of the advantages and limitations of each technique, through the literature research carried out, using recently published worksThe present work was done and funded under the scope of the project ON-SURF (ANI | P2020 | POCI-01-0247-FEDER-024521, co-funded by Portugal 2020 and FEDER, through COMPETE 2020-Operational Programme for Competitiveness and Internationalisation. F.J.G. Silva also thanks INEGI-Instituto de Ciência e Inovação em Engenharia Mecânica e Engenharia Industria, due to its support.info:eu-repo/semantics/publishedVersio