Diminuir a variabilidade de variáveis chaves do processo tornou-se um dos principais caminhos para quantificar os benefícios potenciais da melhoria do controle de processos, ou seja, com maior confiabilidade dos resultados é possível trabalhar em uma região próxima ao ponto de operação ótimo, o que se converte em ganho. Tal ganho pode ser materializado na forma de aumento da capacidade de produção da unidade, redução do consumo de energia, decréscimo de produtos fora de especificação, redução do tempo de transição entre produtos, melhoria na operabilidade, melhoria na qualidade final do produto, entre outros. Na presente dissertação é realizada uma revisão das principais metodologias que visam quantificar o potencial de alteração de variabilidade a qual uma malha de controle possa estar sujeita, além de propor um modelo de inferência que possa ser utilizado para predizer esse potencial de alteração de variabilidade, baseado em índices dados pelo Modelo de Inferência para Desempenho e Robustez. Neste trabalho é mostrado o procedimento utilizado para a construção do Modelo de Inferência de Variabilidade, o qual utiliza como entradas índices que possam ser facilmente quantificáveis e de características da planta (tempo morto e constante de tempo), usando somente dados em operação normal (sem mudanças no valor do setpoint). Para a sua obtenção, três diferentes métodos foram testados (a saber, Rede Neural, Mínimos Quadrados Parciais e Mínimos Quadrados Parciais Quadráticos), sendo os melhores resultados conseguidos ao se aplicar redes neurais. A eficácia do modelo de inferência proposto é ilustrada pela aplicação em casos de estudo nos quais o modelo de planta pode ser representado por funções de transferência de 1ª e de 2ª ordem com tempo morto e a aplicabilidade do mesmo é ilustrada ao utilizá-lo em um caso de estudo, desenvolvido em uma planta industrial. Nesse caso de estudo, procurou-se ainda analisar as principais malhas encontradas no cenário industrial. Os resultados obtidos para ambos os casos de estudo mostraram que a ferramenta desenvolvida apresenta um grande potencial de ser utilizada em projetos que contemplem a análise de pontos de melhoria da camada regulatória, uma vez que apresenta uma excelente capacidade de predizer a alteração de variabilidade a qual uma malha possa estar sujeita. / Reduction of the process variability has a significant impact into the process profitability. A reduction in the variance allows shifting the mean of the controlled variable closer to the constraint and thus ensures better performance like increase product throughput, increase yield of higher valued products, improve energy efficiency, decrease off-specification product, safer operation and reduced environmental impact, among others. In this dissertation, a bibliographic review of the main methodology used to estimate and assess the variance reduction is done. The main contribution of this work is to propose an inferential model to estimate the potential alteration in variance, based on indices determined by the Performance and Robustness Inferential Model. This work shows the procedure to build the Variability Inferential Model that assesses the potential alteration in variance of a given loop. The inputs variables are indices that can be easily calculated on-line and information about the plant (time delay and time constant) using only normal operating data (without excitation and/or setpoint activity). The set of input – output variables are fitted using different techniques (i.e., Neural Networks, Partial Least Squares and Quadratic Partial Least Squares). The best results are obtained by Neural Network. The efficacy of the Inferential Model is illustrated by application to first order plus time delay and second order plus time delay models. The proposed methodology was also applied to on a polyolefin plant, providing very good results, in a set of five loops, where the potential variance alteration is computed with small error, showing the efficacy of the methodology.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / As interrupÃÃes no fornecimento de energia elÃtrica provocam diversos prejuÃzos econÃmicos Ãs concessionÃrias e aos seus clientes cuja extensÃo està associada, principalmente, à freqÃÃncia e duraÃÃo do evento e ao tipo de consumidor. Para as concessionÃrias de distribuiÃÃo de energia elÃtrica, que sÃo fiscalizadas pelos ÃrgÃos reguladores e pela sociedade, o grande desafio à a diminuiÃÃo do tempo das interrupÃÃes e, conseqÃentemente, das perdas econÃmicas por elas ocasionadas. Este trabalho apresenta a concepÃÃo e aplicaÃÃo de uma metodologia de anÃlise de desempenho econÃmico dos serviÃos de atendimento emergencial ao consumidor de energia elÃtrica, considerando os impactos econÃmico-financeiros para a distribuidora e para os consumidores de se utilizar um sistema de gestÃo operacional que otimize os parÃmetros que medem este desempenho. No estudo de caso, efetuado sobre o sistema de atendimento emergencial (SAE) da Companhia de Eletricidade do Cearà â COELCE, tem-se como parÃmetro principal de desempenho a duraÃÃo equivalente da interrupÃÃo (DEC), definida pela AgÃncia Nacional de Energia ElÃtrica - ANEEL. Partindo-se do uso de um sistema computacional de gestÃo otimizadora, desenvolvido na Universidade Federal do Cearà (Sistema SAEDE), o qual otimiza o despacho e a alocaÃÃo das equipes de campo responsÃveis pelos serviÃos de reparo na rede elÃtrica, aplicou-se a metodologia proposta no intuito de verificar se haveria benefÃcios justificÃveis para investimentos em sistemas de gestÃo operacional do SAE tanto para a distribuidora quanto para os consumidores. Os principais resultados obtidos atravÃs da aplicaÃÃo da metodologia ao SAE da COELCE apontou que a utilizaÃÃo do Sistema SAEDE contribui para reduzir custos aos usuÃrios devidos Ãs falhas na entrega de energia pela Companhia e, tambÃm, diminui custos a ela imputados quando ocorrem distÃrbios na rede elÃtrica. / Interruptions in electrical supply system normally cause several economic damages both to supplier companies and to their customers which are hard to be estimated. The extension of these damages is a function of the frequency and duration of the blackout and it varies according to the consumerâs characteristics. In Brazil, electrical supplier companies are regulated by federal and state agencies on behalf of the consumers and their major challenge is to reduce breakdown time and consequent economic losses. This work presents the conception and application of a methodology to make the economic performance assessment of customerâs emergency attendance services, according to the parameters and standards set by the Federal Regulatory Agency (ANEEL) and focusing both the supplier and consumers costs related to system breakdown. The proposed methodology was applied to the case of a electrical distribution company in Ceara State, in the northeastern Brazil, to which an optimized operational management system (SAEDE System) was built. SAEDE System is a computational tool that was developed to optimize the dispatch and the staffing of the emergency attendance teams who are employed to repair electrical fails in the regional system. The proposed methodology was applied to search the benefits of investments derived from using SAEDE System in customerâs emergency attendance services of electrical supply Company in Ceara State. Main results of the study point out that the application of SAEDE System contributes to reduce both customerâs costs as well as company costs related to electrical system breakdown in the study area.

There is an impetus in the UK to move away from empirical pavement foundation design and the current method specification, towards an analytical design approach. For an analytical design approach to be adopted, the required performance properties of stiffness and resistance to permanent deformation of the foundation materials (sub grade and capping) need to be measured, both in the laboratory for design and in the field in order to ensure compliance. This thesis studies the influence of the sub grade on the constructability and performance of a series of full-scale pavement foundations. This has been achieved by measuring the performance parameters of several sub grade materials in the laboratory, using repeated load triaxial testing. These data have been compared to comparable data collected in situ using dynamic stiffness measuring devices during the construction of trial pavement foundations. The performance of the trial foundations has been measured during the placement and compaction of the different foundation materials, and again after their subsequent trafficking. The testing demonstrates the stress dependency of the foundation materials. The laboratory testing shows that the sub grade permanent deformation under cyclic loading (used to simulate construction operations) becomes unstable at a deviator stress of half the deviator stress at failure (0.5qmax)· The stiffness at this applied stress and above is shown to be approaching a consistent value. This indicates that large changes in the stiffness of inversely stress dependent fine grained soils occur below the deviator stress at which the permanent deformation becomes unstable. Significant variability of data has been found in the performance parameters measured (both in the laboratory and in the field) for samples of subgrade collected from small areas of the same site. However comparable patterns of stress dependency have been observed between measured laboratory and field performance using the different apparatus. The resistance to permanent deformation is shown to be a more critical design load case for construction than the need for adequate stiffness of support required to compact the foundation layers. The performance of a composite road foundation is shown to be material and site specific, and this will have important implications for design and site compliance testing.

Clinical performance assessment (CPA), which includes performance criteria, that define what students are expected to learn and practically demonstrate, is used to declare students competent by determining their level of skill. The purpose of this research was to explore student perceptions on the clinical assessment and how assessment contributed to enhancement of competency, and was driven by the question “How do oral hygiene students’ perceptions on clinical performance assessment (CPA) influence their learning experience?” A qualitative approach was followed, rooted in an interpretivist paradigm, using a case study design. The sample consisted of all 19 second-year oral hygiene students who wrote a narrative, and four of the 19 students with whom semi-structured interviews were held. Data was collected by asking the students to write the narratives, and after analysis thereof, the interviews were held. Data was analyzed throughout the data collection process, using a coding framework. The oral hygiene students understood that CPA tested their clinical skills as well as their theoretical knowledge, measures progression and improvement. They expressed negativity about the assessors' inconsistent use of performance criteria, inadequate feedback, and the unprofessional relationship of certain assessors with them. These issues led to frustration, confusion, and demotivation, and impacted negatively on students' learning and competency. Being humiliated in front of the patient or being shouted at led to demotivation. Students coped with assessment by adapting to what an assessor wanted, focusing on patient feedback, and just accepting the results. Students recommended that there be more feedback and discussion with the assessor about strengths and weaknesses. This was how they learned and became competent. They should be allowed to express an opinion and discuss issues with the assessor. / Dissertation (MEd)--University of Pretoria, 2008. / Curriculum Studies / unrestricted

Higher education institutions across the United States have developed global learning initiatives to support student achievement of global awareness and global perspective, but assessment options for these outcomes are extremely limited. A review of research for a global learning initiative at a large, Hispanic-serving, urban, public, research university in South Florida found a lack of instruments designed to measure global awareness and global perspective in the context of an authentic performance assessment. This quasi-experimental study explored the development of two rubrics for the global learning initiative and the extent to which evidence supported the rubrics’ validity and reliability. One holistic rubric was developed to measure students’ global awareness and the second to measure their global perspective. The study utilized a pretest/posttest nonequivalent group design. Multiple linear regression was used to ascertain the rubrics’ ability to discern and compare average learning gains of undergraduate students enrolled in two global learning courses and students enrolled in two non-global learning courses. Parallel pretest/posttest forms of the performance task required students to respond to two open-ended questions, aligned with the learning outcomes, concerning a complex case narrative. Trained faculty raters read responses and used the rubrics to measure students’ global awareness and perspective. Reliability was tested by calculating the rates of agreement among raters. Evidence supported the finding that the global awareness and global perspective rubrics yielded scores that were highly reliable measures of students’ development of these learning outcomes. Chi-square tests of frequency found significant rates of inter-rater agreement exceeding the study’s .80 minimum requirement. Evidence also supported the finding that the rubrics yielded scores that were valid measures of students’ global awareness and global perspective. Regression analyses found little evidence of main effects; however, post hoc analyses revealed a significant interaction between global awareness pretest scores and the treatment, the global learning course. Significant interaction was also found between global perspective pretest scores and the treatment. These crossover interactions supported the finding that the global awareness and global perspective rubrics could be used to detect learning differences between the treatment and control groups as well as differences within the treatment group.

Objective. To evaluate the validity and reliability evidence of the preceptor assessment of student tool (PAST) which was designed to assess doctor of pharmacy (PharmD) student rotation performance. Methods. Evaluation data were loaded into WINSTEPS software to conduct a Rasch rating scale analysis. Validity evidence was examined from construct and content validity perspectives, and reliability was assessed via student and item separation index and reliability coefficient. Data from 435 observations were included in the analysis. Results. All 19 items measured the same construct of interest and the five-point rating scale functioned appropriately and differentiated students' ability. However, the item/person map indicated an absence of items at the end of the measurement continuum. Conclusion. Although adding items at the end of the measurement continuum may be beneficial, PAST showed good validity and reliability evidence when used to evaluate PharmD student rotations and is suitable to assess mastery learning.

L'optique adaptative a révolutionné l'imagerie astronomique en permettant de corriger en temps réel les déformations du front d'onde introduites l'atmosphère, et d'atteindre la limite de diffraction des télescopes. Plus récemment, différentes modalités d'optique adaptative grand-champ ont permis de repousser les limites d'utilisation de ces instruments, compensant l'anisoplanétisme de l'atmosphère, et la faible couverture du ciel. L'asservissement de ces systèmes est sans aucun doute un point clé pour améliorer encore les performances de ces systèmes, pour ainsi converger vers les programmes scientifiques des futurs ELT.Le premier objectif de ces travaux de thèse est de définir un outil général d'analyse de performance, permettant de comparer, sous la forme de budgets d'erreur, différents régulateurs linéaires. Ceci permet d'améliorer les instruments actuels, ou de faire des choix dans la conception des futurs instruments des ELT. Pour cela, un formalisme d'analyse fréquentielle est développé dans le cadre de l'optique adaptative classique, et étendu au cas grand-champ. On montre que cet outil permet aussi bien de décomposer les performances calculées en simulation qu'à partir de données télémétriques enregistrées sur le ciel. De nouvelles stratégies de commande, basées sur de nouveaux modèles de perturbation sont proposées, et leur apport en performance discuté au regard de leur budget d'erreur. Ces résultats ont servi à la caractérisation d'une commande LQG tip-tilt avec filtrage de vibration qui doit être intégrée à l'instrument d'optique adaptative multi-conjuguée GeMS, au Chili. / Adaptive Optics (AO) systems have revolutionized ground-based astronomical imagery, allowing for real-time compensation of turbulence-induced deformations of the optical wavefront, and therefore allowing to reach the diffraction limit. More recently, wide-field AO modalities have been proposed to expand the operational range of instruments by compensating anisoplanatism and increase sky coverage. Controlling such systems is certainly a key issue to further improve their performance and to converge towards the goals of the ELTs science programs.The first objective of this thesis work is to define a general-purpose performance analysis tool, enabling to compare different linear controllers through their error budgets, in order to improve existing instruments or make choices in the design of future instruments. To achieve this aim, a frequency-domain formalism is developed for single-conjugated AO and extended to wide-field configurations. It is shown that this tool allows to decompose controller performance using either simulations or on-sky data. New control strategies based on new disturbance models (turbulence, vibrations...) are proposed, and the improvement in performance is discussed based on their error budget. Furthermore, these results contributed to characterize an LQG controller with vibration mitigation that is to be integrated in the tip/tilt loop of the multi-conjugate AO system GeMS, at Gemini South Observatory, in Chile.

The purpose of this study was to develop a valid and reliable measure and attendant rating scale for the assessment of the sight-reading skills of classical guitarists at the beginning of collegiate study. This study sought to answer the following questions: 1. What musical components and their ranges of values should be measured in a sight-reading assessment for entry-level collegiate classical guitarists? 2. Can a valid and reliable sight-reading assessment for classical guitarists be constructed? 3. Can a rating scale or other scoring mechanism be constructed that would be easy to use and promote a high degree of objectivity and reliability? Tentative standards were drawn from data acquired by means of an electronic survey questionnaire sent to collegiate guitar teachers throughout North America (N = 1,193) which yielded 241 responses. Musical elements that emerged from the survey results were validated by comparison with specific works from the guitar’s literature that were recommended by survey respondents as appropriate for testing sight-reading skills at the college-entry level, as well as with published sample sight-reading exams. The emergent elements were constructed into six short musical exams and a rating sheet for each, loosely patterned after the scoring mechanism of the Watkins-Farnum Performance Scale. These exams constituted the pilot test, which was administered to 14 student volunteers by their college guitar instructors. Internal reliability coefficients were obtained using several methods, all of which were strong (generally in the .82 to .98 range). Interrater reliability coefficients were also strong (.91 to .99). Based on analysis of the pilot results and suggestions from teachers, one of the original assessments was slightly modified, a new assessment was constructed, and rating sheets developed. The same procedures used in the pilot test were followed in the field test, which was administered to 28 volunteer students. Internal reliability using several methods resulted in coefficients generally in the .90 to .96 range, and interrater reliabilities ranged from .87 to .98.

Cloud VR/AR/MR (Virtual Reality, Augmented Reality, and Mixed Reality) services representa high-level architecture that combines large scale computer resources in a data-center structurestyle set up to render VR/AR/MR services using a combination of very high bandwidth, ultralow latency, high throughput, latest 5G (5th Generation) mobile networks to the end users.  VR refers to a three-dimensional computer-generated virtual environment made up ofcomputers, which can be explored by people for real time interaction. AR amplifies humanperception of the real world through overlapping of computer-generated graphics or interactivedata on a real-world image for enhanced experience.  According to the Virtual Reality Society’s account of the history of VR, it started from the360-degree murals from the nineteenth century [18]. Historically, live application of AR wasdisplayed when Myron Kruger used a combination of video cameras and projector in aninteractive environment in 1974. In 1998, AR was put into live display with the casting of avirtual yellow line marker during an NFL game. However, personal, and commercial use ofVR/AR was made possible starting with release of a DIY (Do it Yourself) headset calledGoogle Cardboard in 2014 by Google, which made use of a smartphone for the VR experience.In 2014, Samsung also introduced Gear VR which officially started the competition for VRdevices. Subsequently In 2014, Facebook acquired Oculus VR with the major aim ofdominating the high-end spectrum of VR headset [18]. Furthermore, wider adoption of ARbecame enhanced with the introduction of Apple’s ARKit (Augmented Reality Kit) whichserves as a development framework for AR applications for iPhones and iPads [18].  The first application of VR devices in the health industry was made possible due to healthworkers’ need to visualize complex medical data during surgery and planning of surgery in1994. Since then, commercial production of VR devices and availability of advanced networkand faster broadband have increased the adoption of VR services in the healthcare industryespecially in planning of surgery and during surgery itself [16]. Overall, the wide availabilityof VR/AR terminals, displays, controllers, development kits, advanced network, and robustbandwidth have contributed to making VR and AR services to be of valuable and importanttechnologies in the area of digital entertainment, information, games, health, military and soon. However, the solutions or services needed for the technology required an advancedprocessing platform which in most cases is not cost efficient in single-use scenarios.  The kind of devices, hardware, software required for the processing and presentation ofimmersive experiences is often expensive and dedicated to the current application itself.Technological improvement in realism and immersion means increase in cost of ownershipwhich often affected cost-benefit consideration, leading to slower adoption of the VR services[14] [15]. This is what has led to development of cloud VR services, a form of data-centerbased system, which serves as a means of providing VR services to end users from the cloudanywhere in the world, using its fast and stable transport networks. The content of the VR isstored in the cloud, after which the output in form of audio-visuals is coded and compressedusing suitable encoding technology, and thereafter transmitted to the terminals. The industrywide acceptance of the cloud VR services, and technology has made available access to payper-use-basis and hence access to high processing capability offered, which is used in iipresenting a more immersive, imaginative, and interactive experience to end users [11] [12].However, cloud VR services has a major challenge in form of network latency introduced fromcloud rendering down to the display terminal itself. This is most often caused by otherperformance indicators such as network bandwidth, coding technology, RTT (Return TripTime) and so on [19]. This is the major problem which this thesis is set to find out.  The research methodology used was a combination of empirical and experimental method,using quantitative approach as it entails the generation of data in quantitative form availablefor quantitative analysis. The research questions are: Research Question 1 (RQ1): What are the latency related performance indicators ofnetworked immersive media in mobile health applications? Research Question 2 (RQ2): What are the suitable network structures to achieve an efficientlow latency VR health application?  The answers gotten from the result analysis at the end of the simulation, show thatbandwidth, frame rate, and resolution are very crucial performance indicator to achieve theoptimal latency required for hitch-free cloud VR user experience, while the importance of otherindicators such as resolution and coding standard cannot be overemphasized. Combination ofedge and cloud architecture also proved to more efficient and effective for the achievement ofa low-latency cloud VR application functionality.  Conclusively, the answer to research question one was that, the latency relatedperformance indicators of networked immersive media in mobile health applications arebandwidth, frame rate, resolution, coding technology. For research question two, suitablenetwork structures includes edge network, cloud network and combination of cloud and edgenetwork, but in order to achieve an optimally low-latency network for cloud VR mobile healthapplication in education, combination of edge and cloud network architecture is recommended

Målet med detta arbete har varit att ta fram en metod för att bestämma prestandan för en pumpanläggning samt åtgärdsprogram för dessa. Detta med utgångspunkt från tidigare gjord forskning inom området. Testkörningar, beräkningar och simuleringar visar att det går att bestämma de undersökta anläggningarnas prestanda, samt dess möjligheter till förbättring med den framtagna metodiken. Arbetet visar även att undersökningens referensramar är av stor vikt för att värdera anläggningens prestanda samt kunna bestämma dess förbättringspotential. Testkörningarna gav prov på detta då jämförelsen för en av dessa anläggningar fick baseras på teoretisk och antagen data. Vilket bidrar till osäkerheten i bedömningen av den anläggningens förbättringspotential. Vid avvikelser i prestanda för anläggningen gentemot referensvärden bör förluster i anläggningens individuella delar bestämmas. Detta för att göra förbättringsinsatserna mer effektiva. Exempel på detta är att undvika byte till en effektivare pump när det är dess förutsättningar som det är fel på. De framtagna nyckeltalen visar på att en anläggning med hög verkningsgrad inte alltid kan likställas med lägre energianvändning jämfört med låg verkningsgrad. Vilket liknas med att nyckeltalen för den aktuella eller liknande anläggningar inte kan jämföras rakt av med anläggningar som har andra förutsättningar. Vidare visar studien på vikten av att säkerställa tillgänglig mätdata finns för att utföra analysen av en anläggning. Därmed blir förarbetet för att garantera att önskvärda parametrar blir mätta en dela av anläggningens prestandabedömning och förbättringsarbete. Då varje enskild anläggning har en mängd unika förutsättningar har dessa testanläggningar fått representera en variation av dessa. Vilka måste vid analysen beaktas för varje enskild anläggning för att förbättringarna ska kunna nå dess potential. / The purpose of this thesis has been to create a methodology to determine the performance of a pumping station and action program for it. The starting point of the thesis takes its steps in previously done research in the current field. Continuing with test runs, calculations and simulations shows that it´s possible to determine the performance of the station and improvements of it with the created methodology. The study also shows that frame of reference of the station is an important part of determining it´s performance and it´s potential of improvement. This was proven with the test runs that showed some difficulties in determining the stations intended performance. In those cases the stations is measured with theoretical and assumed values. This adds to the uncertainty of the stations actual potential of improvement. To determine the performance of the station against a reference value it´s important to determine what parts that affects the final result. The cause of that is to get more effective actions plans. Example of that is to avoid changing a water pump when it´s the prerequisites that are affecting the performance of the station. The produced key figures of the stations show that a station with high efficiency is not the same thing as low energy usage compared to a station with low efficiency. That can be compared with the key figures is only comparable with the actual station or ones alike. Other stations differences have to be taken accounted for when make comparisons. The study also reveals the importance of securing the necessary measuring data to be able perform the analysis of the station. Therefore is the preparatory work to acquire the key parameters of the station a part of the study that determines the performance and it´s improvement. Thou each and every station have its unique prerequisites the test run stations have served as an representation of these variations. These prerequisites have to be individually addressed for each and every station to be able to reach it´s potential of improvement.