121 research outputs found
Redesigning a Manufacturing System Based on Functional Independence: The Case of a Tree Nursery
AbstractThe engineering of manufacturing systems encompasses two main areas of development: the manufacturing process (manufacturing technologies, and flow and handling of materials), and the production management (flow of information - signals). These two areas must be designed to perform according to the expressed needs. This paper shows that the Axiomatic Design (AD) theory can be used to analyse a manufacturing system to find the origin of the lack of productivity, and, subsequently, to redesign a solution avoiding the weakness points. A case study of a tree nursery of a large wood production enterprise was used to show the application of the axiomatic design principles, particularly through analysing the design equation and including new design parameters with the independence in mind. The redesign solution based on the independence of functions promoted the simplification of the information (signals) flow, avoiding the identification of each production element, and avoiding errors, which increases the productivity and the production volume, by elimination of waste of time in production operations. The proposed solution brought results that encourage the application of AD to increment the productivity of manufacturing systems, in alternative to expensive investments
O projecto de produtos únicos desenvolvidos em empresas de pequena dimensão
Dissertação apresentada para obtenção do Grau de Doutor em Engenharia Mecânica na especialidade de Projecto de Máquinas pela Universidade Nova de Lisboa,Faculdade de Ciências e TecnologiaO projecto de máquinas novas, desenvolvido em Pequenas e Médias Empresas Industriais,
nos casos em que as quantidades de produtos produzidos, a partir do mesmo projecto, são
muito pequenas, apresenta as características do projecto de protótipos, sendo cada projecto desenvolvido caso a caso e em função das necessidades particulares de cada cliente.
Por outro lado, os factores de escala dessas empresas e os prazos de entrega impostos pelo
mercado inviabilizam a obtenção e utilização de dados rigorosos, sendo o desenvolvimento
dos projectos realizado sob condições de grande incerteza, de diversos tipos e origens,acabando o produto final, que será entregue ao cliente, por ser um protótipo, cujos ensaios são feitos, muitas vezes, em condições reais de utilização.
Dada a inviabilidade de se reduzir por via experimental essas incertezas, foi desenvolvida uma metodologia para o processo de projecto de produtos únicos, de modo a torná-los insensíveis, dentro de limites razoáveis, às incertezas presentes na fase inicial do processo de projectar.
Com esta metodologia, que foi desenvolvida de acordo com as mais recentes teorias e
métodos existentes no âmbito da actividade de projecto, pretende-se minimizar o esforço
necessário para a redução daquelas incertezas, sendo os produtos resultantes desses projectos capazes de se adaptar às diversas condições a que possam vir a estar sujeitos.
Na metodologia criada, são utilizadas técnicas de projecto que incorporam soluções passíveis de serem adaptadas a diferentes situações, quer por modificação dos seus componentes, quer por intermutabilidade de componentes, em concepções modulares, cuja arquitectura é baseada em estruturas do tipo “plataforma”, as quais constituem a base comum a vários tipos de produtos, consoante os módulos que sejam adicionados à referida plataforma.
A metodologia proposta proporciona uma base lógica para uma estratégia do projecto de
engenharia, que leva em conta os modelos do processo de projecto mais adequados ao
projecto de produtos únicos, e que procura integrar, na medida do possível, as práticas de projecto seguidas na indústria. Faz-se, assim, a ligação entre a teoria e a prática do projecto de produtos únicos
A METHOD FOR AUTOMATIC RELOCATION OF SKIN MARKERS IN REARFOOT MOTION ANALYSIS
INTRODUCTION: The authors are collaborating in a project aiming at developing computer based strategies to improve the analysis of the visual and ground reaction forces signal during passive or active foot load. The main objectives of the project are the automatic detection of the skin markers in image sequences for kinematics analysis, and the synchronisation the visual and ground reaction force data acquisition systems to achieve dynamic joint measurements. In this paper, a method for automatic relocation of skin markers in rearfoot motion analysis is proposed. The results of preliminary tests are critically described on full paper.
METHODS: The visual signal is acquired using a high-speed digital camera (DALSA CA-D1), at 225 frames per second. A prototype system is being built, based on an IBM-PC running the Windows NT operating system. A windows interface has been developed, in order to facilitate data analysis. Data can be exported to a spreadsheet or to a statistical package for further processing. The experiments conduced focused on the observation of the ankle joint complex kinematics behaviour on the posterior aspect of the frontal plane during stance phase of walking barefoot. The skin markers have been clearly marked on the rear part of the leg and on the heel (black ink on a white stripe of tape). These markers are localised in the computer screen by hand, using the mouse, in the first frame of the sequence. The markers are automatically located in the other image frames of the sequence, using the proposed method, based on optimised block-matching. The space calibration procedure uses a scale marked by two targets located perpendicularly on the camera axis. These two points mark the horizontal. Comparison between the real measures of one well know rigid body and measures calculated trough the computer helps preventing some misbehaviour of the automatic analysis.
RESULTS: The prototype system was applied to recorded data of angular motion of the ankle joint complex during two walking tasks. Our detailed motion analysis scheme during these motor tasks was successful in using the proposed automatic relocation method, with great economy to the operator.
CONCLUSION: This automatic localisation solution represents a step towards the analysis of sequences acquired with high frame rates, justified by the fact that image acquisition with standard equipment (25 or 30 frames per second) presents strong aliasing problems. The method presented here is expected to be a useful tool for other kinematics behaviour studies
Impact of SM parameters and of the vacua of the Higgs potential in gravitational waves detection
In this work we discuss two different phases of a complex singlet extension
of the Standard Model (SM) together with an extension that also includes new
fermion fields, in particular, a Majoron model equipped with an inverse seesaw
mechanism. All considered scenarios contain a global symmetry
and allow for first-order phase transitions while only two of them are strong
enough to favour the detection of primordial gravitational waves (GWs) in
planned experiments such as LISA. In particular, this is shown to be possible
in the singlet extension with a non vanishing real VEV at zero temperature and
also in the model with extra fermions. In the singlet extension with no
additional fermions, the detection of GWs strongly depends on the
symmetry breaking pattern of the scalar potential at zero
temperature. We study for the first time the impact of the precision in the
determination of the SM parameters on the strength of the GWs spectrum. It
turns out that the variation of the SM parameters such as the Higgs boson mass
and top quark Yukawa coupling in their allowed experimental ranges has a
notable impact on GWs detectability prospects.Comment: 28 pages, 13 figure
EVIDÊNCIA CIENTÍFICA NO USO DA OSTEOPATIA E HIPNOSE CLÍNICA NO TRATAMENTO DOS SINTOMAS DA COVID-19
O objetivo desta revisão bibliográfica . O método da revisão foi de consulta à base de dados dos períodicos PubMed, Periódicos capes, ResearchGate, Jstor, BVS Saúde, do período de 2015 a 2020 com busca avançada cruzada entre o primeiro nome em inglês e português “osteopatia e hipnose clínica” com as variações das palavras: infecção, pneumonia e doenças do aparelho respiratório. Foram encontrados seis estudos com foco em pacientes hospitalizados, dos 638 artigos da osteopatia e 359 da hipnose clínica que atenderam aos critérios de inclusão da revisão bibliográfica. Dentre as técnicas encontradas de uso da Osteopatia estava o tratamento osteopático manipulativo (TMO) na melhoria da dor músculo esquelética, uma das queixas comuns entre os pacientes na pandemia. Para uso de hipnose clínica encontrou-se a utilização da técnica de tratamento de oito sessões em grupo de pacientes, como também em sessões individuais em pacientes com supervisão clínica semestral
Bioanalytical approach-ageing, exercise and oxidative stress
Abstract: Exercise interferes with the ageing, causing changes in markers of the antioxidant system, such as nitric oxide (NO) and uric acid.
Aim: The objective of this study was to evaluate if regular exercise affects the ageing process by causing changes in the antioxidant markers, nitric oxide and uric acid, in individuals aged ≥ 65 years, subjected to an exercise plan.
Methods: The study involved 12 participants distributed in an experimental and control group. The experimental group performed exercises guided by a physiotherapist during 12 weeks. Three blood samples were collected from participants: T0, at the start of the study; T1, after 12 weeks of exercise and T2, 12 weeks after finishing the exercise. NO and uric acid were quantified with commercial kits. The statistics were performed using SPSS and the ANOVA and Student t-tests were applied.
Result: In the experimental group, the mean values of NO showed an increase between T0 and T1, with a slight decrease between T1 and T2. Similar effects were observed for the uric acid concentration in the experimental group, with statistical significance from T0 to T1.
Conclusion: After exercise, there was an increase in blood uric acid and NO levels, highlighting the importance of moderate and controlled exercise practice. Therefore, exercise seems relevant and beneficial in activating antioxidant mechanisms.info:eu-repo/semantics/publishedVersio
Prototype of an affordable pressure-controlled emergency mechanical ventilator for COVID-19
We present a viable prototype of a simple mechanical ventilator intended as a
last resort to ventilate COVID-19 patients. The prototype implements the
pressure-controlled continuous mandatory ventilation mode (PC-CMV) with
settable breathing rates, inspiration/expiration time ratios and FiO2
modulation. Although safe, the design aims to minimize the use of technical
components and those used are common in industry, so its construction may be
possible in times of logistical shortage or disruption or in areas with reduced
access to technical materials and at a moderate cost, affordable to lower
income countries. Most of the device can be manufactured by modest technical
means and construction plans are provided.Comment: This version differs from version 2 in that it includes toxicological
and bio-safety tests and updated electronic
Macroecological patterns of species distribution, composition and richness of the Azorean terrestrial biota
We investigate the macroecological patterns of the terrestrial biota of the Azorean archipelago, namely the species-range size distributions, the distance decay of similarity, and the island species–area relationship (ISAR). We use the most recent up-to-date checklists to describe the diversity at the island level for nine groups (Lichens, Fungi, Diatoms, Bryophytes, Vascular Plants, Nematodes, Molluscs, Arthropods, Vertebrates). The particularities of the Azorean biota result in some differences to the patterns commonly found in other oceanic archipelagos. Strikingly, bryophytes, molluscs and vertebrates show a bimodal species-range size distribution, and vascular plants a right unimodal distribution due the high numbers of widespread species. Such high compositional homogeneity between islands also results in non-significant or even negative decays of similarity with distance among islands for most groups. Dispersal ability, together with other particular characteristics of each taxon, also shapes these distributions, as well as the relationships between island species richness, and area and time. Strikingly, the degree of departure of the richness of the whole archipelago from the SAR of its constituent islands largely depends on the dispersal ability of each group. Comparative studies with other oceanic archipelagos of the globe are however needed to understand the biogeographical and evolutionary processes shaping the remarkably low diversity of the Azorean biota
Descrição da biodiversidade terrestre e marinha dos Açores
1. Os Açores são um arquipélago isolado de nove ilhas oceânicas, pertence à região biogeográfica da Macaronésia e está entre as regiões mais ricas em fungos, plantas e animais da Europa. Este capítulo destaca o que sabemos sobre os fungos, a fauna e a flora dos habitats terrestres, dulçaquícolas e marinhos dos Açores. 2. Neste capítulo, são apresentadas as estimativas do número total de espécies e subespécies conhecidas actualmente nos Açores. Todos os grupos taxonómicos terrestres mais importantes foram analisados: fungos, líquenes, diatomáceas dulçaquícolas, briófitos (musgos, hepáticas e antocerotas), plantas vasculares (licófitas, fetos, gimnospérmicas e angiospérmicas), platelmintes (vermes), nemátodos, anelídeos (minhocas), moluscos terrestres (lesmas e caracóis), artrópodes (insectos, aracnídeos, milípedes, etc.) e vertebrados (peixes de água doce, anfíbios, répteis, aves e mamíferos). A presente obra inclui também espécies do ambiente marinho, como as algas (macroalgas), a maioria dos filos de invertebrados do litoral e os vertebrados marinhos (répteis, peixes e mamíferos). As listas de espécies e subespécies (Capítulos 2-15) são baseadas nos taxa identificados numa grande variedade de publicações, tendo essa informação sido compilada por um vasto grupo de especialistas. 3. Actualmente, o número total de taxa (espécies e subespécies) terrestres nos Açores está estimado em cerca de 6164 (cerca de 6112 espécies). A inclusão de uma listagem exaustiva das espécies de aves não-nidificantes e de uma listagem preliminar de espécies de aves potencialmente nidificantes acrescenta 325 espécies e subespécies ao total das espécies açorianas. 4. O número total de espécies e subespécies endémicas terrestres dos Açores é de cerca de 452 (411 espécies). Os animais são os mais diversos em endemismos, com 331 taxa (Arthropoda = 266; Mollusca = 49; Vertebrata = 14; Nematoda = 2), compreendendo cerca de 73% dos endemismos terrestres dos Açores. A percentagem de endemismo nos Mollusca (44%) é notável. As plantas vasculares contam com 73 endemismos, os Fungi (incluindo os líquenes) têm 34 e, tanto as diatomáceas dulçaquícolas como os briófitos, incluem sete espécies endémicas. 5. Quando comparada com os arquipélagos vizinhos da Macaronésia (Madeira e Canárias), a fauna e flora terrestres dos Açores é caracterizada por uma menor taxa de endemismo, de apenas 7%, contrastando com os cerca de 20% para a Madeira e de 30% para as Canárias. 6. No que diz respeito aos organismos marinhos, são listados 1883 taxa pertencentes a 16 filos. O número total de espécies e subespécies marinhas endémicas dos Açores é de cerca de 39, a maior parte delas moluscos (29 espécies). 7. O número total de taxa terrestres e marinhos (espécies e subespécies) nos Açores, está estimado em cerca de 8047. Os organismos marinhos agora listados, perfazem cerca de 23% da biodiversidade dos Açores. 8. O número total de taxa terrestres e marinhos (espécies e subespécies) endémicos dos Açores está estimado em cerca de 491.ABSTRACT: 1. The Azores is a remote oceanic archipelago of nine islands which belongs to the Macaronesia biogeographical region and is among the richest regions concerning fungi, plant and animal diversity in Europe. This chapter highlights what we know about the Azorean terrestrial, freshwater and marine Fungi, Flora and Fauna. 2. In this chapter we summarize the current estimates of the total number of species and subspecies presently known to occur in the Azores. The most important terrestrial taxonomic groups were studied: Fungi, Lichens, Bacillariophyta (freshwater diatoms), Bryophyta sensu lato (mosses, liverworts and hornworts), vascular plants – Tracheobionta, including Lycopodiophyta (quillworts), Pteridophyta (ferns), Pinophyta (gymnosperms) and Magnoliophyta (angiosperms), Platyhelminthes (flatworms), Nematoda (roundworms), Annelida (earthworms), Terrestrial Mollusca (slugs and snails), Arthropoda (millipedes, centipedes, mites, spiders, insects, etc.) and Vertebrata (freshwater fishes, amphibians, reptiles, birds and mammals). In addition, we expand this list to the marine realm, including Algae (macroalgae), coastal invertebrates (most Phyla) and marine vertebrates (fishes, reptiles and mammals). The list of species and subspecies (Chapters 2 to 15) is based on the taxa recognized in primary published literature sources, compiled by a vast group of experts. 3. Currently the total number of terrestrial taxa (species and subspecies) in the Azores is estimated of about 6164 (about 6112 species). The inclusion of an exhaustive listing of non breeding species and a preliminary list of potentially breeding species adds 325 species and subspecies of birds to the Azorean list of species. 4. The total number of terrestrial endemic species and/or subspecies from the Azores is about 452 (411 species). Animals are the most represented in this respect, with 331 taxa (Arthropoda = 266; Mollusca = 49; Vertebrata = 14; Nematoda = 2), that is, about 73% of the Azorean terrestrial endemics. The percentage of endemism within Mollusca (44%) is remarkable. Vascular plants have 73 endemic taxa, while Fungi (including Lichens) have 34, freshwater diatoms and bryophytes have seven endemic species each. 5. Compared to the other nearest Macaronesian archipelagos (Madeira and Canaries), the Azorean terrestrial fauna and flora is characterized by a lower percentage of endemism (only 7%, which contrasts with nearly 20% for Madeira and 30% for the Canary islands). 6. Concerning the marine organisms, we listed about 1883 taxa belonging to 16 Phyla. The total number of marine endemic species and/or subspecies from the Azores is about 39, most of them being molluscs (29 species). 7. Currently, the total number of terrestrial and marine taxa (species and subspecies) in the Azores is estimated in about 8047. The marine organisms currently listed make up about 23% of the Azorean biodiversity. 8. Currently, the total number of terrestrial and marine endemic taxa (species and subspecies) in the Azores is estimated of about 491
The Azorean Biodiversity Portal: an internet database for regional biodiversity outreach
Copyright © 2010 The Natural History Museum.There is a growing interest in academia to provide biodiversity data to both the scientific community and the public. We present an internet database of the terrestrial lichens, bryophytes, vascular plants, molluscs, arthropods, vertebrates and coastal invertebrates of the Azores archipelago (Portugal, North Atlantic): the Azorean Biodiversity Portal (ABP, http://www.azoresbioportal.angra.uac.pt/). This is a unique resource for fundamental research in systematics, biodiversity, education and conservation management. The ABP was based on a regional species database (ATLANTIS), comprised of grid-based spatial incidence information for c. 5000 species. Most of the data rely on a comprehensive literature survey (dating back to the 19th century) as well as unpublished records from recent field surveys in the Azores. The ABP disseminates the ATLANTIS database to the public, allowing universal, unrestricted access to much of its data. Complementarily, the ABP includes additional information of interest to the general public (e.g. literature on Macaronesian biodiversity) together with images from collections and/or live specimens for many species. In this contribution we explain the implementation of a regional biodiversity database, its architecture, achievements and outcomes, strengths and limitations; we further include a number of suggestions in order to implement similar initiatives
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