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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Identifying Causes of Burden in Ecological Momentary Assessment Studies

Fadahunsi, Simeon, O'Donnell, Grace January 2022 (has links)
No description available.
52

Social Anhedonia in the Daily Lives of People with Schizophrenia: Examination of Anticipated and Consummatory Pleasure

Danielle Abel (16024717) 30 August 2023 (has links)
<p>  </p> <p>Social withdrawal is a disabling feature of schizophrenia. To understand its development, researchers have focused on social anhedonia— diminished pleasure from social interactions. Discrepancies in anticipated versus consummatory pleasure for non-social stimuli are well-documented in schizophrenia. Thus, a similar emotional paradox may underlie social anhedonia. If so, our understanding of social anhedonia—including how to treat it in schizophrenia—could be enhanced. This project used a 5-day experience sampling method (ESM) to measure discrepancies between anticipated and consummatory pleasure for real-world social activities in people with schizophrenia and healthy controls (<em>n=</em>30/group). Results suggest people with schizophrenia exhibited similar levels of anticipated and consummatory social pleasure as controls, and both groups were accurate in their short-term predictions of pleasure. Yet, healthy control participants were somewhat more precise in their short-term pleasure predictions, and clinical interviews revealed those with schizophrenia showed moderate deficits in long-term social pleasure prediction. Negative symptoms and cognitive impairment in schizophrenia were related to anticipated, but not consummatory, social pleasure, suggesting anhedonia is driven by deficits in thinking about pleasure, rather than inability to experience pleasure. Clinical implications include focusing on building upon short-term ability to predict pleasure in therapy in order to increase social motivation in schizophrenia. Moreover, exploratory analyses revealed differences in qualitative aspects of social activities such as level of engagement may lead to social anhedonia in schizophrenia and are a promising treatment target for addressing social dysfunction.</p>
53

Requirements and Analysis of an Overload Protection Mechanism for an Electromechanical Linear Actuator / Kravställning och Analys av Skyddsmekanism mot Överlast för Linjärt Elektromekaniskt Ställdon

Vesterberg, Mats January 2022 (has links)
Cascade Drives specializes in high-performance electromechanical linear actuators (EMA). The company has developed a range of linear rack and pinion actuators based on a patented load distribution technique that allows multiple pinions to interact with a single gear rack. A project where one of their EMAs is to be implemented into an excavator boom is about to be initiated. It is suspected that extreme shock loads are present in such applications. The shock loads could potentially cause problems for the structural integrity of the gear train. This master thesis focused on defining requirements for an overload protection mechanism and identifying and evaluating possible solutions that could be implemented into the EMA to protect it from damage. At the start of the thesis, a pre-study had already been conducted. The author found that the forces present during shock loading warrant some protection strategy to be researched and implemented into the EMA. A comprehensive multibody dynamics model (MBD) of the EMA was developed in MSC Adams (View) to validate the result from the pre-study. The MBD model was later expanded to include a torsional stiffness model derived from physical tests and the flexibility of the excavator boom itself, which was extracted from flexible body simulations of the excavator boom assembly in Adams. The expanded MBD model simulations revealed that a protection mechanism was needed in the thought application. Three protection mechanisms/strategies were simulated and evaluated in the MBD environment. A slipping solution in the form of a friction clutch, a disconnecting solution in the form of an electromagnetic clutch, and an active solution in which the electric motor was controlled to produce maximum torque in the opposite direction of motion at the point of impact to dampen the loads through the gear train. Running the motor in reverse at impact proved to be an insufficient strategy. Even for an idealized motor that combined the maximum torque from the strongest motor and the rotational inertia from the lightest motor available for the EMA, simulations resulted in loads above the static load limit through the gear train. The friction clutch was shown to be plausible but inefficient. The slipping torque of a friction clutch had to be detuned way below the static load limit due to the delays in peak torque throughout the gear train, which meant that the overall actuating force of the actuator was severely hampered. The electromechanical disconnecting clutch was proved to be the most promising alternative. The disconnecting clutch completely disengages the upstream components from the downstream components in the drive train, meaning that the overall system performance remained unchanged. The response times needed depended on where the clutch was installed, from around 16ms if only the motor was disengaged up to 17ms if both the motor and the brake were disengaged. Further analysis of triggering strategies and response times has to be conducted to definitely decide if an electromagnetic clutch is a viable option. Still, the result from this thesis shows that it is a promising path. / Cascade Drives är specialiserade på högpresterande elektromekaniska linjära ställdon. Företaget har utvecklat en rad linjära ställdon av kuggstångskonfiguration som bygger på en patenterad lastfördelningsteknik som möjliggör för flera pinjonger att interagera med en enda kuggstång. Ett projekt där ett av deras ställdon ska implementeras i en grävmaskinsbom är på väg att inledas och man misstänker att det i en sådan applikation kan uppstå extrema chocklaster, vilka potentiellt kan orsaka stora skador på ställdonets drivlina. Detta examensarbete fokuserade på att kravställa och analysera ett överbelastningsskydd och att identifiera och utvärdera olika möjliga lösningar som kan implementeras i ställdonet för att skydda det från skador. En förstudie kring problemet har redan genomförts där författaren fann att de krafter som uppstår vid chocklaster motiverar att någon form av skyddsstrategi undersöks och implementeras i ställdonet. En omfattande multibody dynamics (MBD) modell av ställdonet utvecklades i MSC Adams (View) för att validera resultatet från förstudien. MBD-modellen utvidgades senare till att innefatta en torsionsflexmodell härledd från fysiska tester och även flexibiliteten hos själva grävmaskinbommen som extraherades från flexible body-simuleringar av grävmaskinens bomaggregat i Adams. Resultat från de utökade MBD-modellsimuleringarna visade att en skyddsmekanism behövs för att skydda drivlinan i ställdonet mot överlast i den tänkta grävmaskinsapplikationen. Tre olika skyddsmekanismer/strategier simulerades och utvärderades i MBD-miljön. En glidande lösning i form av en friktionskoppling, en frånkopplande lösning i form av en elektromagnetisk koppling, och en aktiv lösning där elmotorn reglerades till att producera maximalt vridmoment bakåt vid tidpunkten för kollisionen för att minska belastningarna i drivlinan. Att köra motorn bakåt vid kollision visade sig vara otillräckligt. Även för en idealiserad motor som kombinerade det maximala vridmomentet från den starkaste motorn som simulerades med rotationströgheten från den lättaste motorn som simulerades resulterade simuleringar i krafter genom drivlinan överstigande den statiska maxbelastningen. Friktionskopplingen visade sig vara en möjlig men ineffektiv lösning. Friktionskopplingens utlösningsmoment måste trimmas ner långt under den statiska maxbelastningen på grund av tiden det tar för maxbelastningen att propagera genom drivlinan. Detta innebar att ställdonets totala prestanda minskade rejält. Den frånkopplande elektromekaniska lösningen visade sig vara det mest lovande alternativet. Det faktum att den frånkopplande kopplingen helt kopplar bort komponenterna uppströms från komponenterna nedströms i drivlinan innebar att systemets prestanda förblev oförändrad. Svarstiderna som krävdes berodde på var kopplingen var installerad, från cirka 16ms om bara motorn skulle kopplas ur och upp till 17ms om både motorn och bromsen kopplades ur. Ytterligare analyser av utlösningsstrategier och svarstider måste genomföras för att definitivt avgöra om en elektrisk frånkopplande koppling är ett bra alternativ, men resultaten från denna avhandling visar att det är en lovande väg.
54

Anomaly Detection for Water Quality Data

YAN, YAN January 2019 (has links)
Real-time water quality monitoring using automated systems with sensors is becoming increasingly common, which enables and demands timely identification of unexpected values. Technical issues create anomalies, which at the rate of incoming data can prevent the manual detection of problematic data. This thesis deals with the problem of anomaly detection for water quality data using machine learning and statistic learning approaches. Anomalies in data can cause serious problems in posterior analysis and lead to poor decisions or incorrect conclusions. Five time series anomaly detection techniques: local outlier factor (machine learning), isolation forest (machine learning), robust random cut forest (machine learning), seasonal hybrid extreme studentized deviate (statistic learning approach), and exponential moving average (statistic learning approach) have been analyzed. Extensive experimental analysis of those techniques have been performed on data sets collected from sensors deployed in a wastewater treatment plant. The results are very promising. In the experiments, three approaches successfully detected anomalies in the ammonia data set. With the temperature data set, the local outlier factor successfully detected all twenty-six outliers whereas the seasonal hybrid extreme studentized deviate only detected one anomaly point. The exponential moving average identified ten time ranges with anomalies. Eight of them cover a total of fourteen anomalies. The reproducible experiments demonstrate that local outlier factor is a feasible approach for detecting anomalies in water quality data. Isolation forest and robust random cut forest also rate high anomaly scores for the anomalies. The result of the primary experiment confirms that local outlier factor is much faster than isolation forest, robust random cut forest, seasonal hybrid extreme studentized deviate and exponential moving average. / Thesis / Master of Computer Science (MCS)
55

Surveillance de l’état de santé des actionneurs électromécaniques : application à l'aéronautique / Health-monitoring of electromechanical actuators : application to aeronautics

Breuneval, Romain 21 December 2017 (has links)
L’industrie aéronautique fait face à trois enjeux majeurs : la réduction de son empreinte environnementale, l’absorption de l’augmentation du trafic et le maintien d’un haut niveau de sécurité pour des systèmes de plus en plus complexes, à coûts équivalents. La maintenance prédictive permet de répondre en partie à ces trois enjeux. Les systèmes, dont on peut prédire la durée de vie peuvent être utilisés plus longtemps, ce qui diminue le nombre de composants utilisés sur la vie d’un avion. Prédire les pannes permet également d’augmenter la disponibilité des aéronefs en évitant les arrêts non planifiés. Enfin, le suivi de l’état de vieillissement de l’avion permet d’optimiser la maintenance et ainsi de réduire les coûts. Dans les années 2000, ces méthodologies ont été appliquées sur les moteurs. Elles commencent maintenant à se généraliser aux autres systèmes avioniques. Ainsi cette thèse concerne la mise au point de méthodologies amenant à la maintenance prédictive d’actionneurs électro – mécaniques (EMA) de commande de vol. Les problématiques et les contraintes (temps de calculs, quantités de mémoire…) liées à cette thématique sont détaillées. Dans un premier temps, le calcul de signatures de défauts est abordé. Une méthode pour les systèmes visécrou, basée sur l’identification d’un modèle de frottement, est proposée. Une deuxième méthode, reposant sur l’analyse des courants à partir d’une combinaison de décomposition modale empirique ensembliste complète et d’analyse aveugle de sources, est ensuite introduite. Ces deux méthodes sont testées sur des données issues de profils non opérationnels. Ces données sont issues d’un modèle de simulation représentant finement l’actionneur dans son environnement. L’ensemble des simulations représente des essais virtuels sur une population d’EMA. A partir de ces simulations, les signatures mises au point sont calculées. Puis, afin de valider ces signatures, des métriques de performances sont calculées. Le diagnostic par reconnaissance de formes est ensuite traité. Un algorithme reposant sur une combinaison de machine à vecteur de supports et de fonctions floues d’appartenances est proposé. Celui-ci peut notamment estimer la sévérité d’un défaut. Il permet également de détecter des points ne correspondant pas à la base d’apprentissage, qui peuvent représenter des défauts inconnus ou des points appartenant à plusieurs classes à la fois, pouvant représenter des cas de défauts combinés. L’architecture d’un système de diagnostic complet, basée sur l’algorithme conçu, est détaillée. Des validations expérimentales des méthodes de calcul de signatures et de diagnostic sont ensuite menées. Ces validations reposent sur trois bases issues de trois campagnes d’essais. La première repose sur des essais d’un EMA sain sur un banc représentatif. La deuxième concerne un moteur asynchrone en défaut en régime permanent. La dernière porte sur un moteur synchrone à aimants, de type aéronautique, en défaut de courtcircuit inter-spires en régime permanent. Le respect des contraintes par l’algorithme est vérifié. Enfin, des éléments pour aller vers le pronostic sont avancés. Le processus du pronostic est détaillé. Seule une partie de ce processus est traitée, sur des données issues de vieillissement de roulements. Dans un premier temps, le partitionnement de données de vieillissement pour créer des classes de sévérité de défaut est étudié. Cette tâche a amené à proposer une métrique, dite de cohérence temporelle, permettant de vérifier qu’un résultat de partitionnement satisfait aux contraintes pour le pronostic. Puis l’algorithme de classification proposé est validé sur les données partitionnées. Ceci amène à distinguer deux méthodes de validation, une approche dite diagnostic et une dite pronostic. Une méthode de normalisation, pour l’approche pronostic, est proposée. La prédiction des signatures dans le futur est ensuite traitée. Un algorithme de régression par vecteurs de support est utilisé [etc...] / The aeronautics industry is facing three major challenges: the reduction of its environmental impact, the absorption to the air traffic increase and a high level of safety for increasing complex systems, for equivalent costs. Predictive maintenance allows answering to these issues. Systems, for which the life can be predicted, can be used for a longer time. This reduces the number of components used in the lifetime of an aircraft. To predict failures also allow increasing the availability of aircrafts by avoiding unplanned downtime. Finally, monitoring the ageing of the aircraft allows to optimize maintenance and so to reduce costs. In the 2000s, these methodologies were applied to turbojets. It starts, now, to be generalized to others avionics systems. Therefore, this work deal with predictive maintenance methodologies for electromechanical actuator (EMA) for flight controls systems. Problems and constraints (computation time, memory quantities…) related to this subject are detailed. In a first part, fault feature computation methodologies are investigated. A first method is proposed for screw/nut systems. This method is based on the identification of a friction model. A second method, based on current analysis, is presented. This method uses a combination of empirical mode decomposition and independent component analysis. The two methods are tested on data from a non-operational profile. This data are from a simulation model which represents the EMA in the aircraft environment. The simulations performed represent virtual trials on a population of EMA. From these simulations, fault features are computed. Then, performances metrics are evaluated. Diagnosis by pattern recognition is then studied. An algorithm based on support vector machine and fuzzy membership functions is proposed. This algorithm can estimate the severity of a fault. It can also detect unknown observations, which can represent unknown faults or combined faults. The architecture of a global diagnosis system, based on the proposed algorithm, is detailed. Experimental validation of fault features computation and diagnosis algorithm is performed. These validations are based on three data bases. The first one is based on trials performed on a healthy EMA on a representative bench. The second consists in an induction motor at constant speed for different types of faults. The last one is from trials on a permanent magnet synchronous machine, of aeronautics type, for different kinds of short – circuit fault severities. The respect of the aeronautics constraints is verified. At last, elements for prognosis process are given. This process is detailed. Only a part of this process is treated, on a roller bearings benchmark database. First, the clustering for prognosis is studied. A metric, which allows verifying that the obtained clusters are coherent regarding time, and thus, checks the constraints for prognosis, is given. Then the proposed diagnosis algorithm is validated on the clustered data. This brought to perform two kinds of validation, a diagnosis oriented one and a prognosis oriented one. A method to normalize data for the prognosis oriented validation, based on sigmoid function, is given. The prediction of the features in the future is studied. A regression algorithm based on support vector regression is used. Finally, the diagnosis algorithm is applied to the predicted data. This allows to estimate the end of life, and so the remaining useful life for a given time. These estimations are evaluated regarding different kinds of performance metrics and regarding the constraints of the aeronautics applicative field
56

Ema Bovaryová a Tereza Desquegrová: ženy destruktivní nebo oběti? / Emma Bovary and Thérese Desquegroux: destructive womwn or victims?

Dobrovolná, Petra January 2012 (has links)
anglicky : Title of the thesis : Emma Bovary and Thérèse Desqueyroux : destructive women or victims ? Keywords : literature, G. Flaubert, F. Mauriac, Emma Bovary, Thérèse Desqueyroux, destructive women , victims, comparison Abstract : The thesis deals with two female characters of French novels from the 2nd half of the 19th century, Madame Bovary by Gustave Flaubert and Thérèse Desqueyroux by Françoise Mauriac. The life and work of the two authors are briefly described as well as the time when they lived. The longer part of the thesis presents a content analysis and a formal analysis of the novels. The thesis places particular emphasis on the analysis of the story, the main characters and turning points in their lives. The aim is then to compare the two heroines based on the previous analysis of the novels and to highlight what they have in common and in what they differ and to answer the question of whether or not Emma Bovary and Thérèse Desqueyroux are victims, victims of circumstances, or whether they are inherently destructive and rightly described as monsters. All the important points of the thesis are summarized in the conclusion.
57

Dimensioning Tools of MEA Actuator Systems, Including Modeling, Analysis and Technology Comparison

Torabzadeh-Tari, Mohsen January 2008 (has links)
Aircraft design is an example of complex engineering where dimensioning tools can be valuable for the designers and decision makers in the early stage of the development process. These tools can be in form of a database over key numbers for different components or technologies. One of the critical parts of an aircraft is the actuator system. Conventional hydraulic actuators are demanding regarding maintenance which implies high operation costs. Therefore in recent years the focus has been set on electro-hydrostatic and electro-mechanical actuators. The aim of this work is to build a platform which can make it easier for designers and decision makers to analyze, compare and optimize different technologies regarding the actuator system. For this reason a simplified quasi-static actuator model, including reactive power consumption has been developed. This model makes it possible to reduce the complexity of the actuator models to such extent that the resulting computional tool can be used for studies of the system performance during entire flight missions and/or for optimization. Power density, cost and weight of the actuator systems are some of the important key numbers for comparing purpose and as a platform for the dimensioning of the aircraft. The ambition is then to build up a database of different actuator solutions with the key technical parameters mentioned above, that can be used in modeling and dimensioning of an aircraft. In order to avoid time consuming finite element calculations when analyzing an electrical machine a reluctance network model can be used. The basic idea of the proposed network model is to divide the rotor and the stator into a grid of small reluctance elements and provide those that correspond to the permanent magnet and the air gap between the magnets with time varying reluctances. The suggested computationally approach constitute a fast way to evaluate permanent magnet electrical machines with the respect to their performance. A preferred electrical machine provided with balance teeth and concentrated windings showed good electromechanical and thermal behavior. A balance tooth is a tooth without winding between each adjacent phases that has a cooling effect on the nearest windings, resulting in less copper losses. The balance teeth increases the voltage-time area, leading to higher induced voltage and higher torque production. Another advantage of the chosen design is its redundancy and fault tolerance capabilities. The machine comprises two independent half machines that also offers a high level of redundancy with two separate power channels. / QC 20100914
58

Talking Story about Art and Life: Narratives of Contemporary Oceanic Artists and Their Work

Yamauchi, Chikako January 2014 (has links)
Talking Story about Art and Life: Narratives of Contemporary Oceanic Artists and Their Work takes a narrative, biographical approach to examine the lives and selected works of five contemporary Oceanic artists living and working in Aotearoa New Zealand – Ioane Ioane, Ema Tavola, Brett Graham, Robin White, and Siliga David Setoga. The narrative methodology, inspired by the Hawaiian notion of “talking story,” utilises informal conversations as sites of knowledge production. This approach allowed more personal and varied information to emerge, which speaks to the pluralities of identity. Instead of focusing primarily on visually analysing the creative output of the artists, their artworks and practices are incorporated as aspects of their voices that contribute to the narratives of their lives. The participants told stories that engage with the complexities intrinsic to their lives, revealing areas to research for the purpose of supporting their narratives. The supporting research investigates the notion of vā, Oceanic curatorial practices, trickster discourse, insider/outsider discourse, and fa‘a Sāmoa. In carrying out this investigation, this thesis illustrates choices artists are making to express their voices on their own terms. Bringing to light these choices also reminds viewers/readers that we can actively shape our own narratives. By privileging the artists’ stories told in their own words, this thesis honours Oceanic oral traditions and moves forward our understanding of these contemporary Oceanic artists and their artistic practices.
59

Techninės analizės taikymas Lietuvos vertybinių popierių rinkoje spekuliaciniai tikslais / Usage of technical analysis for speculative purposes in lithuanian stock market

Pekšys, Darius 26 June 2014 (has links)
Lietuvoje privatūs asmenys (spekuliantai) vis dažniau pasirenka įvairesnes investicijos formas. Viena iš sparčiai populiarėjančių investicijos formų – prekyba akcijomis Lietuvos vertybinių popierių biržoje tarpininkaujant finansų maklerių įmonėms. Investuotojai/spekuliantai norėtų žinoti, ar teorijoje aprašyta techninė analizė gali suteikti pakankamai informacijos, kad būtų galima apsispręsti, pirkti ar parduoti akcijas. Darbo tikslas yra nustatyti ar taikytini yra techninės analizės matematiniai modeliai Lietuvos vertybinių popierių rinkoje. Buvo taikomi penki pagrindiniai techninės analizės matematiniai modeliai: - paprastąjį slankųjį vidurkį (SMA); - eksponentinį slankųjį vidurkį (EMA); - slankaus vidurkio konvergencijos ir divergencijos indikatorių (MACD); - santykinio stiprumo indeksą (RSI); - stochastinį indikatorių; Buvo sukurta programinė įranga kuri, analizuodama pagal statistinius duomenis matematinių modelių generuojamus pirkimo pardavimo signalus, skaičiavo prekybos rezultatus. Tyrimo rezultatai parodė, kad krypties indikatorių SMA, EMA bei MACD naudojimas Lietuvos vertybinių popierių rinkoje pasitvirtino. Osciliatorių naudojimas Lietuvos vertybinių popierių rinkoje davė arba prastus arba neigiamus rezultatus. / There are more and more private persons (speculators) who a choosing different types of investment in Lithuania. More people are willing to participate in the stock trade in the Lithuanian stock market with brokers mediation. Investors/speculators are willing to know if technical analysis, that is well described in the theory, can give enough information that could lead to decision to buy or sell the stock. The goal of this study is to identify if the mathematical models, that are described by technical analysis, are possible to use in Lithuanian stock market. The mathematical models are: - simple moving average, SMA; - exponential moving average, EMA; - moving average convergence and divergence, MACD; - relative strength indicator, RSI; - Stochastic oscillator. The software was developed to calculate the result of all possible trades. All trades were made after receiving the signals according to mathematical calculations when statistic data where entered. The result of the study proved with positive results the use of trend indicators like SMA, EMA and MACD in Lithuanian stock market. The use of oscillators is not offered to use in Lithuanian stock market according to study results.
60

Energia metabolizável aparente para poedeiras Isa Label mantidas em ambiente de alta temperatura / Apparent metabolizable energy for Isa Label laying kept in high temperature environment

Macchi, Paloma de Matos 16 July 2015 (has links)
Made available in DSpace on 2016-08-15T20:31:32Z (GMT). No. of bitstreams: 1 PalomaMM_DISSERT.pdf: 1913188 bytes, checksum: a5ce6f6f4c89b77f39177c6480f067a3 (MD5) Previous issue date: 2015-07-16 / Brazil stands out in poultry production as the largest exporter and third largest producer of chicken, and among the ten largest producers of eggs. The demand for food and population growth make the poultry production chain essential to agribusiness, regional economy and strengthening family agriculture, providing highly nutritious affordable food. Genetic improvements and research in pet nutrition favored the success of the poultry industry in the country, however, there is little research on nutritional requirements for slow growth bloodlines in hot climate regions. The Isa Label is a strain with naked neck, slow growth bloodlines with two option for products, which has been widely used by farmers for being good producer of eggs and meat have with appreciable flavor. The amount of metabolizable energy used in feed is conditional factor for productivity of laying in high temperature conditions, and has considerable weight in food costs. The aim of this study was to determine the requirement of apparent metabolizable energy (AME) to Isa Label bird dual purpose in laying phase, 52 weeks old, under high temperature conditions, by evaluating performance, quality eggs and economic viability. They were distributed at random 90 laying in five treatments with nine replicates of two birds each. The treatments were 2,600; 2,675; 2,750; 2,825 and 2,900 kcal / kg of EMA in the feed. We evaluated: feed intake and EMA, laying rate, egg weight, egg mass, feed conversion and energy per mass and dozen eggs; and quality characteristics of eggs. The economic analysis was performed with the number of eggs produced, feed consumption and price per kilogram of feed. The results were productive performance and egg quality were statistically analyzed by polynomial regression with probability <5% significance level. The results of the economic analysis were submitted to descriptive statistics. Increasing the EMA level in poultry feed Isa Label in laying phase, not compromise performance between 52 and 64 weeks of age. The level 2,778 kcal / kg of EMA in the ration showed lower feed intake, while the 2,638 kcal / kg EMA level in the diet had lower power consumption under high temperature environment conditions. Internal and external quality of the eggs was not affected by EMA level in feed, but increased EMA in diets increased the width of the albumen and egg. The use level of 2,675 kcal / kg of EMA is economically viable for poultry Isa Label in stance phase, from 52 to 64 weeks of age under high temperature conditions / O Brasil se destaca na produção avícola como maior exportador e terceiro produtor mundial de frango, e entre os dez maiores produtores de ovos. A demanda por alimentos e o crescimento populacional tornam a cadeia produtiva avícola essencial ao agronegócio, economia regional e fortalecimento da agricultura familiar, fornecendo alimento de alto valor nutritivo a preço acessível. Melhorias genéticas e pesquisas em nutrição animal favoreceram o sucesso da avicultura no país, contudo, existem poucas pesquisas em exigências nutricionais para linhagens de crescimento lento em regiões de clima quente. A Isa Label é uma linhagem com pescoço pelado, crescimento lento e dupla aptidão, que vem sendo muito utilizada pelos criadores por ser boa produtora de ovos e possuir carne com sabor apreciável. A quantidade de energia metabolizável utilizada nas rações é fator condicional para produtividade de poedeiras em condições de altas temperaturas, e tem peso considerável nos custos com alimentação. O objetivo com este trabalho foi determinar a exigência de energia metabolizável aparente (EMA) para aves Isa Label de dupla aptidão em fase de postura, com 52 semanas de idade, sob condições de alta temperatura, por meio da avaliação de desempenho, qualidade de ovos e viabilidade econômica. Distribuíram-se ao acaso 90 poedeiras em cinco tratamentos, com nove repetições de duas aves, por unidade experimental. Os tratamentos foram: 2.600; 2.675; 2.750; 2.825 e 2.900 kcal/kg de EMA na ração. Avaliou-se: consumo de ração e de EMA, taxa de postura, peso do ovo, massa de ovo, conversão alimentar e energética por massa e dúzia de ovos; e características de qualidade de ovos. A análise econômica foi realizada com número de ovos produzidos, consumo de ração e preço por quilograma da ração. Os resultados foram de desempenho produtivo e qualidade de ovos foram submetidos à análise estatística por regressão polinomial com probabilidade < 5% de significância. Os resultados da análise econômica foram submetidos à estatística descritiva. O aumento do nível EMA na ração para aves Isa Label, em fase de postura, não comprometeu desempenho entre 52 e 64 semanas de idade. O nível 2.778 kcal/kg de EMA na ração apresentou menor consumo de ração, enquanto o nível 2.638 kcal/kg de EMA na ração apresentou menor consumo de energia, sob condições de alta temperatura ambiente. A qualidade interna e externa dos ovos não foi afetada pelo nível de EMA nas rações, porém o aumento de EMA nas rações aumentou a largura do albúmen e do ovo. A utilização do nível 2.675 kcal/kg de EMA é economicamente viável para aves Isa Label, em fase postura, entre 52 a 64 semanas de idade, sob condições de alta temperatura

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