Peroxidase antibody test for mucocutaneous leishmaniasis serology performance indexes and comparison with a fluorescent antibody test: Comparação com o desempenho da reação de imunofluorescência

Performance indexes of the peroxidase antibody test were compared to that of the fluorescent antibody test. The peroxidase antibody test had a statistically higher sensitivity and negative predictive value and a higher efficiency than the fluorescent antibody test but its specificity and positive predictive value were within the 95% confidence limits for the values found for the fluorescent antibody test. Such differences did not change when Chagas' disease and visceral leishmaniasis sera were included in index calculations. Statistical analysis showed that the two tests have a substantial degree of agreement but the immunofluorescent test had a specificity index and a positive predictive value equal to 100.0% when Chagas' disease and visceral leishmaniasis sera were not included in the calculations of the performance index; in this instance, a positive test result equals a disclosure of the disease attribute due to the inexistence of false positive results. The enzyme/ protein ratio of the peroxidase conjugate, resulting in heavy or light-labeled conjugates may pose technical problems to its use in serology tests.

Performance indexes of a dot-enzime-linked immunosorbent assay (dot-ELISA) and an ezyme-linked immunosorbent assay (IgG-ELISA) for field surveys of new world leishmaniasis

Diagnostic performance indexes of sensitivity, specificity, positive predictive value and efficiency were determined for dot-ELISA and IgG-ELISA tests in 340 leishmaniasis sera. Sensitivity of the dot-ELISA was significantly lower than IgG-ELISA's; the two tests had indexes of specificity and positive predictive value of the same magnitude. Seventy-eight sera gave a negative dot-ELISA test result and a positive IgG-ELISA test result. When sera were classified according to different criteria as how to interpret this diversity, the kappa statistic did not corroborate the classification indicating that the two tests display a substantial strength of agreement. The results presented indicate that performance indexes accrued in a survey where variables arc well known may be extrapolated to other population studies if the disease presents itself as highly prevalent (due to a selection bias or not) and may be expected to discriminate a disease status among test positives.

A comparison of performance indexes in DC-DC converters under different stabilizing state-dependent switching laws

This paper deals with the problem of establishing stabilizing state-dependent switching laws in DC-DC converters operating at continuous conduction mode (CCM) and comparing their performance indexes. Firstly, the nature of the problem is defined, that is, the study of switched affine systems, which may not share a common equilibrium point. The concept of stability is, therefore, broadened. Then, the central theorem is proposed, from which a family of switching laws can be derived, namely the minimum law and the hold state law. Some of these are proved to stabilize the basic DC-DC converters and then, their performances are compared to another law, from a previous work, by simulation, where a great reduction in overshoot is obtained. © 2011 IEEE.

Selection of early-maturing sweet orange cultivars by performance indexes

The objective of this work was to select adequate early-maturing sweet orange cultivars for the fresh fruit market and for industrial processing using performance indexes. Performance indexes for citrus were established from data collected in an experiment carried out in the southwest region of the state of Sao Paulo, involving 12 early-maturing sweet orange cultivars. New results were obtained by identifying cultivars with superior characteristics. In a comparison with 'Hamlin' sweet orange, a standard early-maturing cultivar, 'Valencia 2' and 'Salustiana' were considered better materials for the fresh fruit market, whereas 'Westin' sweet orange was identified as a superior cultivar for orange juice processing.

Dimensional synthesis of a spherical parallel manipulator based on the evaluation of global performance indexes

In this work, the dimensional synthesis of a spherical Parallel Manipulator (PM) with a -1S kinematic chain is presented. The goal of the synthesis is to find a set of parameters that defines the PM with the best performance in terms of workspace capabilities, dexterity and isotropy. The PM is parametrized in terms of a reference element, and a non-directed search of these parameters is carried out. First, the inverse kinematics and instantaneous kinematics of the mechanism are presented. The latter is found using the screw theory formulation. An algorithm that explores a bounded set of parameters and determines the corresponding value of global indexes is presented. The concepts of a novel global performance index and a compound index are introduced. Simulation results are shown and discussed. The best PMs found in terms of each performance index evaluated are locally analyzed in terms of its workspace and local dexterity. The relationship between the performance of the PM and its parameters is discussed, and a prototype with the best performance in terms of the compound index is presented and analyzed.

Acumulação tecnológica e aprimoramento de performance competitiva: evidências de diferenças e similaridades e médias empresas do setor metal-mecânico no estado do rio de janeiro

The main objective of this dissertation is to examine the implications of technological capacities in the improvement of technical performance indexes, specifically at the company level. These relationships were examined in a small sample of metal-working enterprises in the state of Rio de Janeiro (1960 to 2006). Although diverse studies on technological competences have been carried out in the last twenty years, a gap in empirical studies still exist that correlate the performance of companies in the context of developing countries, especially in Brazil. Aiming to contribute to a reduction of these gaps, this dissertation examines the questions by the light of available models in literature, which opting themselves to using operational indexes of companies. For drawing the accumulation of technological competences in this study, the metric proposal by Figueiredo (2000) shall be used indicating the levels of technological qualification in process, product, and equipment functions. The empirical evidence examined in this dissertation is both qualitative and quantitative in nature and were collected, first hand, through extensive field research involving informal interviews, meetings, direct-site observation and document analysis. In relation to the results, the evidence suggests that: - In terms of technological accumulation, a company reached Level 5 of technological capacity in process and organization of production as well as product and equipment. Three companies obtained Level 4 in the function process function while two others had reached the same technological level in the functions of product and equipment. Two companies had reached Level 3 in the product and equipment functions and one remained this level in the function of process; - In terms of the rate of accumulation of technological capacities, the observed companies had reached Level 4 needs 29 years in process function, 32 years in product function and 29 years in equipment function; - In terms of improvement performance pointers, a company which reached Level 5 of technological capacity improved in 70% of its indicators of performance, while the company that had achieved Level 4 had raised its pointers 60% and the other companies had gotten improved in the order of 40%. It was evidenced that the majority of the pointers of the companies with higher levels of technological capacities had obtained better performance. This dissertation contributes to advancing the strategic management of companies in metal-working segment to understanding internal accumulation of technological capacity and indicators of performance especially in the field of empirical context studied. This information offers management examples of how to improve competitive performance through the accumulation of technological capacities in the process, product and equipment functions.

A state-space modeling approach for active structural acoustic control

The demands for improvement in sound quality and reduction of noise generated by vehicles are constantly increasing, as well as the penalties for space and weight of the control solutions. A promising approach to cope with this challenge is the use of active structural-acoustic control. Usually, the low frequency noise is transmitted into the vehicle`s cabin through structural paths, which raises the necessity of dealing with vibro-acoustic models. This kind of models should allow the inclusion of sensors and actuators models, if accurate performance indexes are to be accessed. The challenge thus resides in deriving reasonable sized models that integrate structural, acoustic, electrical components and the controller algorithm. The advantages of adequate active control simulation strategies relies on the cost and time reduction in the development phase. Therefore, the aim of this paper is to present a methodology for simulating vibro-acoustic systems including this coupled model in a closed loop control simulation framework that also takes into account the interaction between the system and the control sensors/actuators. It is shown that neglecting the sensor/actuator dynamics can lead to inaccurate performance predictions.

Projecto de Controladores usando Redes Neuronais

Neste documento descreve-se o projeto desenvolvido na unidade curricular de Tese e Dissertação durante o 2º ano do Mestrado de Engenharia Eletrotécnica e de Computadores no ramo de Automação e Sistemas, no Departamento de Engenharia Eletrotécnica (DEE) do Instituto Superior de Engenharia do Porto (ISEP). O projeto escolhido teve como base o uso da tecnologia das redes neuronais para implementação em sistemas de controlo. Foi necessário primeiro realizar um estudo desta tecnologia, perceber como esta surgiu e como é estruturada. Por último, abordar alguns casos de estudo onde as redes neuronais foram aplicadas com sucesso. Relativamente à implementação, foram consideradas diferentes estruturas de controlo, e entre estas escolhidas a do sistema de controlo estabilizador e sistema de referência adaptativo. No entanto, como o objetivo deste trabalho é o estudo de desempenho quando aplicadas as redes neuronais, não se utilizam apenas estas como controlador. A análise exposta neste trabalho trata de perceber em que medida é que a introdução das redes neuronais melhora o controlo de um processo. Assim sendo, os sistemas de controlo utilizados devem conter pelo menos uma rede neuronal e um controlador PID. Os testes de desempenho são aplicados no controlo de um motor DC, sendo realizados através do recurso ao software MATLAB. As simulações efetuadas têm diferentes configurações de modo a tirar conclusões o mais gerais possível. Assim, os sistemas de controlo são simulados para dois tipos de entrada diferentes, e com ou sem a adição de ruído no sensor. Por fim, é efetuada uma análise das respostas de cada sistema implementado e calculados os índices de desempenho das mesmas.

Application of near surface mounted (NSM) strengthening technique to traditional timber frame walls

Timber frame buildings are well known as an efficient seismic resistant structure popular all over the world not only due to their seismic performance, but also to their low cost and the strength they offer. These constructions still exist today and it is important to be able to preserve them, so a better knowledge on their behaviour is sought. Furthermore, historic technologies could be used even in modern constructions to build seismic resistant buildings using more natural materials with lesser costs. A great rehabilitation effort is being carried out on this type of buildings, as their neglect has led to decay or their change in use and alterations to the structure has led to the need to retrofit such buildings; only recently studies on their behaviour have become available and only a few of them address the issue of possible strengthening techniques for this kind of walls. In this scope, an innovative retrofitting technique (near surface mounted steel flat bars) is proposed and validated on traditional timber frame walls based on an extensive experimental program. The results of the static cyclic tests on distinct wall typologies retrofitted with the NSM technique are herein presented and discussed in detail. The main features on deformation, lateral stiffness, lateral resistance and seismic performance indexes are analysed

Traditional timber frame walls: mechanical behavior analysis and retrofitting

Timber frame construction is characteristic of several historic city centres as well as of vernacular architecture in several countries around the world, either motivated by the availability of materials and construction traditions or by the need of reducing the seismic vulnerability of buildings, namely in south European countries, where this construction technique was adopted for seismic-resistance purposes. From past earthquakes, it has been seen that timber frame construction can be viewed as an interesting technology as it has exhibited a very reasonable behaviour when compared to other traditional construction techniques such as masonry walls. This chapter provides an overview of the main insights on the seismic performance of timber frame buildings from the evidences of past earthquakes and provides the main results of recent research focused on the in-plane cyclic behavior of timber frame walls with distinct geometrical configurations. Additionally, the main seismic performance indexes of timber frame walls, both unreinforced and retrofitted, are presented and discussed in detail.

Common snook fed in alternate and continuous regimens with diet supplemented with Bacillus subtilis probiotic

The objective of this work was to evaluate the addition of Bacillus subtilis probiotic to the feed of common snook (Centropomus undecimalis) fingerlings, in alternate and continuous regimens. Six hundred and sixty fish, with average length of 5.90±0.88 cm and weight of 1.92±0.28 g, were stocked in 12 cages of 1.0 m3, with 55 fish each. The experimental design was completely randomized, with three treatments and four replicates. The treatments consisted of diet with the addition of probiotic, provided in alternate regimen for 7 days and in continuous regimen; besides a control without probiotic in the feed. Zootechnical performance, body composition, immune response, and blood parameters were evaluated. No significant differences were observed in zootechnical performance indexes and in body composition of fish treated with probiotic, when compared to the control. Fish from the alternate regimen showed an increment in respiratory burst and a lower total erythrocyte count than fish from the continuous regimen and the control. Fish from the continuous regimen did not differ from those of the control. The addition of Bacillus subtilis does not increase growth rates of common snook fingerlings; however, it has an immunostimulant action when supplied in alternate regimen.

Paperikoneen laatusäätöjärjestelmän uusinnan vaikutukset laatusäätöjen suorituskykyyn

Tutkimuksen kohteena olleen UPM-Kymmene Oyj Kajaanin tehtaan PK3:n laatusäätöjärjestelmä ja mittapalkki uusittiin, jolloin haluttiin selvittää uusinnan vaikutuksia laatusäätöjen suorituskykyyn ja paperin laatuun. Työn kirjallisessa osassa perehdyttiin paperinvalmistusprosessin osiin kyseisen sanomalehtipaperikoneen tapauksessa sekä keskeisimpiin paperin laatuominaisuuksiin liittyviin mittaus- ja säätölaitteisiin sekä niiden toimintaan. Seurattaviksi paperin laatusuureiksi valittiin neliömassa, kuivamassa, kosteus ja paksuus, jotka ovat sanomalehtipaperin tärkeimpiä online-mitattavia ominaisuuksia. Paperin laatusuureiden seurantaan käytetään erilaisia tunnuslukuja ja työkaluja, joita on esitelty tässä työssä. Laatusuureiden konesuuntaisen ja poikkisuuntaisen seurannan tunnusluvuksi valittiin yleisesti käytössä oleva 2σ-keskiarvohajonta. Säätöjen suorituskykyä seurattiin suorituskykykolmion ohjausmatkaindeksien (CTI) ja erosuureen integraalien (IAE) avulla. Kokeellisessa osassa kerättiin mittaustietoja sekä vanhan että uuden laatusäätöjärjestelmän aikana. Seurattavat ajotilanteet paperikoneella jaettiin stabiiliin ajoon ja muutostilanteisiin, jotka käsittävät katkot ja lajinvaihtotilanteet. Stabiilin ajon aikana selvitettiin laatusuureiden hajontojen ja säätöjen suorituskykyindeksien normaaleissa tasoissa tapahtuneet muutokset. Muutostilanteiden osalta haluttiin selvittää, nopeuttaako järjestelmäuusinta katkoista toipumista ja lajinvaihtoaikaa. Stabiilin ajon seurannasta saatujen tulosten perusteella neliömassan ja kuivamassan konesuuntaiset hajonnat kasvoivat järjestelmäuusinnan myötä, mutta kosteuden konesuuntaiset hajonnat pienenivät. Laatusuureiden poikkisuuntaisista hajonnoista neliömassan sekä kuivamassan hajonnat kasvoivat ja kosteuden sekä paksuuden hajonnat pienenivät joidenkin lajien osalta. Poikkisuuntaisten laatusuureiden, etenkin paksuuden, toipuminen katkon jälkeen nopeutui. Myös lajinvaihtoon kuluva aika lyheni poikkisuuntaisilla laatusuureilla. Muutostilanteiden konesuuntaisten hajontojen asettumisajat eivät juuri parantuneet.

Using passive techniques for vibration damping in mechanical systems

This paper examines two passive techniques for vibration reduction in mechanical systems: the first one is based on dynamic vibration absorbers (DVAs) and the second uses resonant circuit shunted (RCS) piezoceramics. Genetic algorithms are used to determine the optimal design parameters with respect to performance indexes, which are associated with the dynamical behavior of the system over selected frequency bands. The calculation of the frequency response functions (FRFs) of the composite structure (primary system + DVAs) is performed through a substructure coupling technique. A modal technique is used to determine the frequency response function of the structure containing shunted piezoceramics which are bonded to the primary structure. The use of both techniques simultaneously on the same structure is investigated. The methodology developed is illustrated by numerical applications in which the primary structure is represented by simple Euler-Bernoulli beams. However, the design aspects of vibration control devices presented in this paper can be extended to more complex structures.

Vibration Attenuation in Rotating Machines Using Smart Spring Mechanism

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)