2,768 research outputs found
Parametrização automática de equipamentos de controlo de qualidade de diferentes tipos de condensadores
Dissertação de Mestrado em Engenharia Industrial - Automação e RobóticaA crescente necessidade do aumento da produtividade e da qualidade na
fabricação de produtos revolucionou o desenvolvimento industrial, visando a
utilização de novas tecnologias na produção, no sentido de aumentar a eficiência
e a flexibilidade das máquinas e dos processos industriais. Estes factores, aliados
à necessidade de criar novos produtos que obedeçam a regras e requisitos de
mercado muito restritos, conduziu à concepção e desenvolvimento das máquinas
SMA e SMAP na Vishay Electrónica Portugal.
É neste contexto que se apresenta o trabalho efectuado no âmbito desta
dissertação, orientando o estudo e a implementação de um sistema que efectue a
Parametrização Automática de Equipamentos de Controlo de Qualidade de
Diferentes Tipos de Condensadores.
As máquinas existentes no teste do controlo da qualidade na produção são
caracterizadas por não serem capazes de dar resposta às exigências de mercado,
uma vez que estas foram concebidas para a produção em massa.
Na sua maioria as máquinas referidas, apresentam problemas de flexibilização,
afinação e desempenho devido à sua baixa fiabilidade mecânica e aos seus
processos ainda muito manuais. Todos estes factores condicionam a garantia da
qualidade dos produtos fabricados.
O software desenvolvido permite ao operador validar a programação da máquina e
dos instrumentos de medida através da leitura óptica do código de barras 2D de
forma automática. As interfaces foram desenvolvidas com tecnologia Touch
Screen, tendo sempre presente o ambiente industrial, a facilidade de operação e
as restrições de operação.
A comunicação do software pela porta RS-232 com o autómato programável
(PLC) permite visualizar a distribuição de condensadores, os gráficos da evolução
da produção, as distribuições de Lote e Turno e o estado da máquina e dos
instrumentos de medida.
Nesta base, a integração das máquinas de teste SMA e SMAP, com o sistema
informático baseado numa plataforma cliente – servidor, possibilita a
automatização do processo de programação da máquina e dos instrumentos de
medida e interligação com outros softwares de apoio à produção, sistemas
operativos e base de dados.
As parametrizações, distribuições e anomalias são guardadas em base de dados
SQL Server na fase de Fecho de Controlo de Lote. Esta metodologia contribui
para a melhoria do processo de controlo da qualidade.The increasing necessity of improving the productivity and the quality in the
manufacture of products revolutionized the industrial development, aiming at the
use of new technologies in the production, in order to increase the efficiency and
the flexibility of the machines and the industrial processes. These factors, together
with the necessity to create new products that obey to the rules and very restricted
requirements of market, lead to the conception and development of machines SMA
and SMAP in Vishay Electrónica Portugal.
It is in this context that we present the work made in the scope of this dissertation,
guiding the study and the implementation of a system that makes the Automatic
Parametrization of Equipment of Quality control of Different Types of Capacitors.
The existing machines in the quality control test in the production are characterized
by not being capable to give reply to the market requirements, once these had
been conceived for the production in mass.
In their majority the related machines, present problems of flexibilization, refining
and performance due to their low mechanical reliability and to their still very
manual processes.
All these factors condition the guarantee of the manufactured product quality.
The developed software allows the operator to validate the programming of the
machine and the instruments of measure through the optic reading of the barcode
2D of automatic form.
The interfaces had been developed with Touch Screen technology, having always
present the industrial environment, the easiness of operation and the restrictions of
operation.
The communication of software by the RS-232 gate with the programmable
controller (PLC) allows to visualize the distribution of capacitors, the graphs of the
evolution of the production, the distributions of Lot and Shift and the state of the
machine and the instruments of measure.
In this base, the integration of the test machines SMA and SMAP, with the
informatics system based in a client - server platform, makes possible the
automatization of the process of programming the machine and the instruments of
measure and interconnection with other softwares of support to the production,
operative systems and database.
The parametrizations, distributions and anomalies are kept in database SQL
Server in the phase of Closing of Control of Lot. This methodology contributes for
the improvement of the process of control of the quality
Functional characterization of mitochondrial suspensions by cytofluorimetric techniques towards the screening of mitochondrial target drugs
Dissertação de mestrado em Bioquímica AplicadaBesides its role in respiration, mitochondria control other key metabolic
pathways, cell proliferation and regulated cell death, with a crucial role in the
regulation of the intrinsic apoptotic pathway. Recent studies have focused on the
screen for anti-cancer agents that induce apoptosis through permeabilization of the
mitochondrial outer membrane, leading to the cytosolic release of pro-apoptotic
proteins and to the activation of the caspase cascade and consequently to cell
dismantling.
In the present study, staining protocols were developed and optimized aiming
at the structural and functional characterization of isolated mitochondrial populations
from yeast cells and rat liver by flow cytometry. Mitotracker Green and Nonyl Acridine
Orange were used to measure changes in mitochondrial mass, 3,3'-
Dihexyloxacarbocyanine Iodide and Mitotracker Red CMXROS to monitor the electrical
potential of the inner membrane (Δψm), Mitotracker Red CM-H2XROS and
Dihydroethidium to evaluate the accumulation of ROS, and 2',7'-Bis-(2-Carboxyethyl)-
5-(and-6)-Carboxyfluorescein and Acetoxymethyl Ester (BCECF-AM) to measure the pH
of the mitochondrial matrix. Subsequent flow cytometry studies were designed to
evaluate the effect in mitochondria function of two well-known apoptosis inducers in
both mammalian cell lines and yeast cells, namely bovine lactoferrin (bLf) and acetate,
and to understand whether or not they act directly on mitochondria independently of
upstream cellular pathways. The results showed that both bLf and acetate promoted
changes in mitochondrial mass, matrix mitochondrial pH, Δψm and ROS levels of rat
liver mitochondria. Moreover, the assessment of the activity of the complexes of
electron transport chain (ETC) showed that bLf and acetate affect their activity and
trigger mitochondrial swelling. These results are particularly interesting since the two
compounds appear to induce in isolated mitochondria mainly the same alterations as
those occurring in whole cells, and which have been proposed to be involved in the
induction of cell death. Altogether, this study show that flow cytometry is a valuable
tool to study key mitochondrial functional parameters and to screen for mitochondriatargeted
drugs, including the anticancer agents, such as acetate and bLf.Para além do seu papel na respiração celular, as mitocôndrias controlam outros
aspetos chaves do metabolismo, bem como a proliferação celular e a morte celular
regulada, tendo um papel crucial na regulação da via apoptótica intrínseca. Estudos
recentes têm-se focado na procura de agentes anticancerígenos capazes de induzir
apoptose mediada pela permeabilização da membrana mitocondrial externa,
conduzindo à libertação de proteínas pró-apoptóticas e à ativação da cascata de
caspases e consequente desmantelamento celular. No presente estudo, foram
desenvolvidos e otimizados protocolos de marcação com vista à caracterização
estrutural e funcional por citometria de fluxo de populações de mitocôndrias isoladas
de células de levedura e de hepatócitos de rato. As sondas Mitotracker Green e laranja
de nonil-acridina foram usadas para medir variações da massa mitocondrial, o iodeto
de 3,3'-Dihexiloxacarbocianina e o Mitotracker Red CMXROS para medir o potencial
eléctrico da membrana mitocondrial interna (Δψm), o Mitotracker Red CM-H2XROS e
dihidroetídeo para avaliar a acumulação de ROS e o acetoximetil éster de (2',7'-Bis-(2-
Carboxietil)-5-(and-6)-carboxifluoresceína e(BCECF-AM) para medir o pH da matriz
mitocondrial. Os estudos subsequentes de citometria de fluxo foram desenhados para
avaliar o efeito de diferentes drogas na função mitocondrial, em particular da
lactoferrina bovina (bLf) e do acetato, dois reconhecidos indutores de apoptose, no
sentido de se compreender se atuam diretamente na mitocôndria independentemente
de outras vias celulares a montante. Os resultados mostraram que tanto a bLf como o
acetato promovem alterações na massa mitocondrial, pH da matriz mitocondrial, Δψm
e nos níveis de ROS em mitocôndrias isoladas de fígado de rato. Além disso, a avaliação
da atividade dos complexos da cadeia de transportadora de eletrões (ETC) mostrou
que a bLf e o acetato afetam a sua atividade e desencadeiam a tumefação
mitocondrial. Estes resultados são particularmente interessantes uma vez que os dois
compostos parecem induzir, em mitocôndrias isoladas as mesmas alterações que
ocorrem em células inteiras, e que têm sido propostas como estando envolvidas na
indução da morte celular. No seu conjunto, este estudo mostra que a citometria de
fluxo é uma ferramenta valiosa para o estudo da funcionalidade mitocondrial e para o
rastreio de drogas que têm como alvo a mitocôndria, incluindo agentes
anticancerígenos, tais como a bLf e o acetato
EDUCATION IN ORAL HEALTH: A Reflective Approach for Quality of Life.
This work aims at critical reflection on the actions that determine a good level of oral health. Health promotion is a process that can positively affect the quality of life of a population. Dental problems have a low priority compared to diseases considered to be of social relevance. Prevention of oral diseases must be developed at three levels: primary, secondary and tertiary. Self-diagnosis is extremely important, because the sooner the problem is detected and prevention services are activated, the greater the chances of an effective treatment. Among oral health problems, dental caries is considered a damage that deserves higher priority due to its high prevalence. Oral cancer gained the second degree of priority, due to its severity, followed by periodontal diseases. Education in oral health has been increasingly required, taking into account the low cost and the possibilities of dental impact on public health. Therefore, the role of educating should not be the exclusive responsibility of the professional conventionally called teacher, but of any citizen.This work aims at critical reflection on the actions that determine a good level of oral health. Health promotion is a process that can positively affect the quality of life of a population. Dental problems have a low priority compared to diseases considered to be of social relevance. Prevention of oral diseases must be developed at three levels: primary, secondary and tertiary. Self-diagnosis is extremely important, because the sooner the problem is detected and prevention services are activated, the greater the chances of an effective treatment. Among oral health problems, dental caries is considered a damage that deserves higher priority due to its high prevalence. Oral cancer gained the second degree of priority, due to its severity, followed by periodontal diseases. Education in oral health has been increasingly required, taking into account the low cost and the possibilities of dental impact on public health. Therefore, the role of educating should not be the exclusive responsibility of the professional conventionally called teacher, but of any citizen
Hospital competition under patient inertia: do switching costs stimulate quality provision?
Recent empirical evidence establishes previous use as a strong predictor of patient choice of hospital and indicates that switching costs explain a significant share of inertia in the hospital industry. In a model of competition between two semi-altruistic and horizontally differentiated hospitals with inherited demand, I investigate the effect of lower switching costs on quality provision and show that it depends on the hospitals' production technology and degree of altruism. If cost substitutability (complementarity) between quality and output is sufficiently weak (strong) relative to altruism, lower switching costs reduce quality at the high-volume hospital, average quality, and patient welfare. While milder patient preferences increase the scope for an increase in quality at both hospitals, it can only occur if hospitals are semi-altruistic. Finally, I show that the distribution of patients between hospitals matters. Even if hospital-level quality and patient welfare increase, lower switching costs may lead to lower average quality.This paper is financed by National Funds of the FCT – Portuguese Foundation for Science and Technology within
the project UID/ECO/03182/2019. I also thank FCT for the PhD Studentship SFRH/BD/129073/2017, financed
by National Funds of the FCT and the European Social Fund (ESF)
Effects of spin-orbit coupling on the Berezinskii-Kosterlitz-Thouless transition and the vortex-antivortex structure in two-dimensional Fermi gases
We investigate the Berezinskii-Kosterlitz-Thouless (BKT) transition in a
two-dimensional (2D) Fermi gas with spin-orbit coupling (SOC), as a function of
the two-body binding energy and a perpendicular Zeeman field. By including a
generic form of the SOC, as a function of Rashba and Dresselhaus terms, we
study the evolution between the experimentally relevant equal
Rashba-Dresselhaus (ERD) case and the Rashba-only (RO) case. We show that in
the ERD case, at fixed non-zero Zeeman field, the BKT transition temperature
is increased by the effect of SOC for all values of the binding
energy. We also find a significant increase in the value of the Clogston limit
compared to the case without SOC. Furthermore, we demonstrate that the
superfluid density tensor becomes anisotropic (except in the RO case), leading
to an anisotropic phase-fluctuation action that describes elliptic vortices and
antivortices, which become circular in the RO limit. This deformation
constitutes an important experimental signature for superfluidity in a 2D Fermi
gas with ERD SOC. Finally, we show that the anisotropic sound velocities
exhibit anomalies at low temperatures, in the vicinity of quantum phase
transitions between topologically distinct uniform superfluid phases.Comment: 5 pages, 3 figure
Quantum phase transitions and Berezinskii-Kosterlitz-Thouless temperature in a two-dimensional spin-orbit-coupled Fermi gas
We study the effect of spin-orbit coupling on both the zero-temperature and
non-zero temperature behavior of a two-dimensional (2D) Fermi gas. We include a
generic combination of Rashba and Dresselhaus terms into the system
Hamiltonian, which allows us to study both the experimentally relevant
equal-Rashba-Dresselhaus (ERD) limit and the Rashba-only (RO) limit. At zero
temperature, we derive the phase diagram as a function of the two-body binding
energy and Zeeman field. In the ERD case, this phase diagram reveals several
topologically distinct uniform superfluid phases, classified according to the
nodal structure of the quasiparticle excitation energies. Furthermore, we use a
momentum dependent SU(2)-rotation to transform the system into a generalized
helicity basis, revealing that spin-orbit coupling induces a triplet pairing
component of the order parameter. At non-zero temperature, we study the
Berezinskii-Kosterlitz-Thouless (BKT) phase transition by including phase
fluctuations of the order parameter up to second order. We show that the
superfluid density becomes anisotropic due to the presence of spin-orbit
coupling (except in the RO case). This leads both to elliptic vortices and
antivortices, and to anisotropic sound velocities. The latter prove to be
sensitive to quantum phase transitions between topologically distinct phases.
We show further that at a fixed non-zero Zeeman field, the BKT critical
temperature is increased by the presence of ERD spin-orbit coupling.
Subsequently, we demonstrate that the Clogston limit becomes infinite:
remains non-zero at all finite values of the Zeeman field. We
conclude by extending the quantum phase transition lines to non-zero
temperature, using the nodal structure of the quasiparticle spectrum, thus
connecting the BKT critical temperature with the zero-temperature results.Comment: 17 pages, 7 figure
Mobile contextual information gathering concerning a phone number
Nowadays there are many communication channels that people can use to communicate with each other and mobile phones continue to be one of the most used. Most of the mobile phones used today are smartphones having features such as Internet access or allowing the installation of third party applications.The advances in mobile technolgies alongside the increasing use of social networks and related applications for smartphones contributed to the increasing amount of information shared by people and companies today. On one side, this increasingly available information can be helpful to a person when trying to contextualize an incoming phone call; on the other side, it can also be helpful to companies employees' that talk to customers (for example, sales people or technical assistance people) having access to information about the person they are talking to helping them understand the context of a call and enabling them to offer a better service.Although there is increasingly available information about people and companies, the information can be spread across different places. Besides, there is the risk that the information stored is not accessed before or in the moment a person talks to another making it useless. Therefore, it would be interesting to aggregate the information available from different sources about a phone number and present it when needed (for example, when receiving a phone call).To address the problem described before, a prototype of an Android application for Smartphones was developed that tries to identify the person or company associated with a phone number collecting, in real time, information about that person or company. The collection and processing of the information resorts to parallel searches in different sources simultaneously using the information obtained in a source to search on another (chain collection). The information can come from public and/or private sources of information (only appliable for companies as they can resort to customers' databases) being displayed in a pop-up while in a phone call or when searching for a phone number
- …