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- Lean Six Sigma Approach to Improve the Production Process in the Mould Industry: a Case StudyPublication . Pereira, António M.H.; Silva, Miguel R.; Domingues, Mercedes A.G.; Sá, José C.Purpose: The purpose of this article is to explore the optimization of internal process is assumed as a critical factor to be capable of answering to the moulds industries. Consequently, it has been considered essential to adopt high-valued methodologies to support tooling industry in order to achieve global competitive advantages. For that purpose, this work aims to apply LEAN principles and techniques to support mould design and manufacturing processes. Methodology/Approach: The methodology used was based on PDCA/DMAIC, with the following stages: Define, Measure, Analyze, Improve and Control. For each stages was taken some of Lean Six Sigma techniques, such as Continuous Improvement, Value Stream Mapping, Pareto analysis and Overall Equipment Effectiveness. Findings: This study results was revealed that there are many areas on the organizations in the Mould Industry, when they utilize otimizations tools obtain hugt successes. With the Pareto analysis was carried out to show that events that contributes the most to the stops. The results were: unavailability of the operator (16.4%), programming the machine (14.4%) and tool exchange (12.4%) In the case of this Mould Industry study was obtained for the CNC machines studies, with the implementation of Lean Six Sigma tools as obtained a improvement about 20% of global OEE. Research Limitation/implication: This research was revealed that there the moulds are Project unique and difficult to analyze. Moreover, this paper reports that the approach LEAN Six Sigma is very interesting for the continuous improvement of processes and profitability of moulds industry. Originality/Value of paper: This research highlight areas of future research using of quality management methods and Lean Six Sigma tools to analyse and optimize production in the moulds industry. Therefore this research It is considered to promote and adopt high-valued methodologies to support tooling industry in order to achieve global competitive advantages.
- Development of an Additive Manufacturing System for the Deposition of Thermoplastics Impregnated with Carbon FibersPublication . Reis Silva, Miguel; Pereira, António M.; Alves, Nuno; Mateus, Gonçalo; Mateus, Artur; Malça, C.This work presents an innovative system that allows the oriented deposition of continuous fibers or long fibers, pre-impregnated or not, in a thermoplastic matrix. This system is used in an integrated way with the filamentary fusion additive manufacturing technology and allows a localized and oriented reinforcement of polymer components for advanced engineering applications at a low cost. To demonstrate the capabilities of the developed system, composite components of thermoplastic matrix (polyamide) reinforced with pre-impregnated long carbon fiber (carbon + polyamide), 1 K and 3 K, were processed and their tensile and flexural strength evaluated. It was demonstrated that the tensile strength value depends on the density of carbon fibers present in the composite, and that with the passage of 2 to 4 layers of fibers, an increase in breaking strength was obtained of about 366% and 325% for the 3 K and 1 K yarns, respectively. The increase of the fiber yarn diameter leads to higher values of tensile strength of the composite. The obtained standard deviation reveals that the deposition process gives rise to components with anisotropic mechanical properties and the need to optimize the processing parameters, especially those that lead to an increase in adhesion between deposited layers.
- Study on the fatigue strength of AA 6082-T6 adhesive lap jointsPublication . Pereira, António; Ferreira, J.M.; Antunes, F.V.; Bartolo, PauloA research study on the fatigue behaviour of aluminium alloy adhesive lap joints was carried out to understand the effect of surface pre-treatment and adherends thickness on the fatigue strength of adhesive joints. The adherend material used for the experimental tests was an aluminium alloy 6082-T6 in the form of thin sheets, and the adhesive used was a high strength epoxy (Araldite 420 A/B). The surface preparation included an abrasive preparation (AP joints) and sodium dichromate-sulphuric acid etch (CSA joints). A maximum fatigue strength was obtained for the CSA surface treatment with a 1.0 mm adherends' thickness. The fastest fatigue damage was related with a high surface roughness and a high stress perpendicular to adhesive surface, which helps to promote the adhesive failure. A numerical analysis was also performed to understand the effect of the adherends thickness on the stress level. Results showed an increase of the out-of-plane peak stresses with the increase of adherends thickness.
- Blind Guide: anytime, anywherePublication . Yánez, Daniel Vera; Marcillo, Diego; Fernandes, Hugo; Barroso, João; Pereira, AntónioEyesight is an important sense that helps humans to avoid dangers and navigate in our world. Blind people usually have enhanced accuracy and sensibility of their other natural senses in order to sense their surroundings. But sometimes this is not enough because the human senses can be affected by external sources of noise or disease. That is why technology has been used to develop many assistive tools. Artifacts like white canes or braille compasses help blind people moving around in the environment. In this article, the use of a system that detects and recognize nearby objects or obstacles is proposed, giving an audible feedback to the user. It is designed as a wireless system in order to be comfortable to be carried by the user. The system helps visual impaired people to move around in indoor or outdoor scenarios. The goals of this blind guide system is to detect obstacles that white canes or dogs cannot, extending its detection range.
- Integrated e-Healthcare System for Elderly SupportPublication . Pires, Pedro; Moreira Mendes, Luís Miguel; Mendes, Jorge; Rodrigues, Rúben; Pereira, AntónioThe fast rise of the population aging verified in the last decades brings new challenges to the modern societies. Most elderly persons have the usual problems related to the old age, like health chronic problems and sensory and cognitive impairments. Therefore, it becomes essential to ensure the quality of life, safety and well-being to all elderly persons. The evolution of the sensors technology, low-power microelectronics and wireless communication standards allows that the gerontechnology be increasingly available and present in our society. This paper presents an integrated e-healthcare system for elderly support, which allows monitoring the biomedical parameters of a person in real time, anywhere and in any situation without interfering with its daily routines. The developed system comprises a personal biomedical data acquisition subsystem and an information storage center. The developed sensorial devices are responsible for acquiring and transmit wirelessly the biomedical signals to a smartphone or tablet. The collected information can also be saved in a storage center, where it can be managed and maintained. The medical data are accessible to the responsible entities for creating the medical history of the elderly persons to ensure a well-founded diagnosis. The high processing capacity of the developed electronic system enables the implementation of advanced algorithms for detection of health problems in order to ensure the safety and wellbeing of the elderly throughout the day. The medical assistance platform also provides to the elderlies telemedicine consultations in the comfort of their home if the videoconferencing service of the platform is used.
- A Java Software Stack for Resource Poor Sensor Nodes: Towards Peer-to-Peer JiniPublication . Costa, Nuno; Pereira, António; Serôdio, CarlosSensor networks have been referred to as part of the background infrastructure required to achieve ubiquitous computing. This has recently promoted a considerable amount of attention from the research community that concluded that existing protocols and techniques for service discovery, such as JINI or UPnP are not suitable for the case of resource poor, battery-powered sensor nodes. We do not really agree with this approach. We think that those protocols could be a good starting point to "power-up" sensor nodes with poor resources for ubiquitous computing support. Starting from this principle and recognizing that existing sensor node system software is not suitable for our purpose, we decided to build a new sensor node software stack. The result was a stand-alone Java Virtual Machine, suitable for sensor nodes with poor resources, an implementation of the ubiquitous TCP/IP communication stack and Jini based middleware to achieve automatic service discover and usage. This software stack was tailored to perfectly fit in the state-of-the-art Mica2 class of sensor nodes.
- IntelligentCart: Architecture of an Innovative System for the Acquisition of Products in Grocery StoresPublication . Santos, Diana S.S.; Pereira, António; Gonçalves, RamiroLarge grocery stores are nowadays used by millions of people for the acquisition of an enlarging number of products. Product acquisition represents a complex process that comprises time spent in corridors, product location and checkout queues. On the other hand, it is becoming increasingly difficult for retailers to keep their clients loyal and to predict their needs due to the influence of competition and the lack of tools that discriminate consumption patterns. In this article it is presented the proposal of an architecture and solution of an innovative system for the acquisition of products in grocery stores (IntelligentCart). The IntelligentCart explores emerging mobile technologies and automatic identification technologies (such as RFID) as a way to improve the quality of services provided by retailers and to augment the consumer value thus allowing to save time and money.