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Yes / This work investigates how batch reactors can be optimized to increase the yield of a desired product coupling two appealing techniques for process control and optimization: the nonlinear model predictive control (NMPC) and the dynamic real-time optimization (D-RTO). The overall optimization problem is formulated and applied to calculate the optimal operating parameters of a selected case study and the numerical results are compared to the traditional control/optimization techniques. It has been demonstrated in our previous work (Pahija et al, Selecting the best control methodology to improve the efficiency of discontinuous reactors, Computer Aided Chemical Engineering, 32, 805-810, 2013) that the control strategy can significantly affect optimization results and that the appropriate selection of the control methodology is crucial to obtain the real operational optimum (with some percent of improved yield). In this context, coupling NMPC and D-RTO seems to be the ideal way to improve the process yield. The results presented in this work have been obtained by using gPROMS® and MS C++ with algorithms of BzzMath library.

Trata do desenvolvimento de um porta-ferramenta translativo (PFT). Objetiva o microposicionamento relativo ferramenta/peça durante a usinagem de ultraprecisão, para atender à tolerâncias nanométricas. Define esse microposicionamento com o emprego de atuador piezelétrico. Mostra alguns aspectos de projeto aplicados à engenharia de precisão que foram usados no desenvolvimento do PFT. Relata as técnicas de controle aplicadas como PID e compensador por atraso de fase. Realiza uma análise para verificação dos modos de vibrar do PFT, identificando assim as freqüências naturais do sistema. Apresenta um modelo ideal, ou seja, todos os componentes foram fabricados e montados para a realização dos testes. Propõe que a estratégia de controle seja baseada em processar sinais adquiridos ao longo do microposicionamento da ferramenta para identificar a condição de posicionamento relativo ferramenta/peça e obter informações que foram posteriormente usadas em um controlador PID, para realimentação de posição. Conclui com a avaliação e testes experimentais de deslocamento da ferramenta de corte, até 25 &#956m; com freqüência, até 10 Hz, realizados com o PFT projetado. / This work deals with the development of a tool post (PFT) for the micropositioning of a tool during ultraprecision machining in the nanometric range. Micropositioning employing piezoelectric actuators is defined. Precision engineering designs aspects applied to the development of the PFT are discussed. Control techniques such as PID and phase-lag compensator are addressed. A computer simulation for the verification of the vibrating modes of the PFT, with the simultaneous identification of the natural frequencies is carried out. An ideal model - all components will be manufactured and assembled - is presented. A control strategy based on the processing of signals acquired during the micropositioning of the tool to identify the positioning condition and to obtain information to be used by a PID controller is proposed. Experimental tests are performed with displacement of the tool, up to 25 &#956m, with frequency, up to 10 Hz.

This study focuses on why people not longer want to be a part of a religious communion they have earlier been a part of. To examine this I have made seven interviews with people who have left their previous communions. Together with the methodological and theoretical discussions on discourse analysis, Richard Jenkins discussions on identity and theories concerning the post-modern society, I have made an analysis on how these people consider their previous communions and its members. They refer i.e. to the social control, the ‘closed’ culture and the non-questioning-culture that constitute the communions and its techniques. They also question why the communions present themselves as ‘good’, despite their deficiencies. Here I claim that in the same time these people question these techniques, they get exposed by them.

Syftet med föreliggande studie är att undersöka vilket synsätt som råder bland lärare i de lägre årskurserna gällande begreppet bedömning. Studiens metodologiska - och teoretiska utgångspunkter grundar sig i Foucaultiansk teoribildning. Empirin har samlats in genom två stycken fokusgruppintervjuer och materialet har analyserats med utgångspunkt i begrepp som governmentality och disciplinär makt. Resultatet visar att lärarna använder sig av flera styrtekniker som inryms av en dold maktutövning, vars primära mål är att forma och styra subjektet. / The purpose of this study is to describe and discuss the function of assessment in primary school. The methodological and the theoretical foundation take its point of departure in theories formulated by Michel Foucault. The empirical data is collected through two focus group interviews and the material is analyzed through the concepts of governmentality and power formations. The results show that teachers use multiple control techniques which are governed by a hidden exercise of power, with the primary aim to shape and control the subject.

<p>This study focuses on why people not longer want to be a part of a religious communion they have earlier been a part of. To examine this I have made seven interviews with people who have left their previous communions. Together with the methodological and theoretical discussions on discourse analysis, Richard Jenkins discussions on identity and theories concerning the post-modern society, I have made an analysis on how these people consider their previous communions and its members. They refer i.e. to the social control, the ‘closed’ culture and the non-questioning-culture that constitute the communions and its techniques. They also question why the communions present themselves as ‘good’, despite their deficiencies. Here I claim that in the same time these people question these techniques, they get exposed by them.</p>

Trata do desenvolvimento de um porta-ferramenta translativo (PFT). Objetiva o microposicionamento relativo ferramenta/peça durante a usinagem de ultraprecisão, para atender à tolerâncias nanométricas. Define esse microposicionamento com o emprego de atuador piezelétrico. Mostra alguns aspectos de projeto aplicados à engenharia de precisão que foram usados no desenvolvimento do PFT. Relata as técnicas de controle aplicadas como PID e compensador por atraso de fase. Realiza uma análise para verificação dos modos de vibrar do PFT, identificando assim as freqüências naturais do sistema. Apresenta um modelo ideal, ou seja, todos os componentes foram fabricados e montados para a realização dos testes. Propõe que a estratégia de controle seja baseada em processar sinais adquiridos ao longo do microposicionamento da ferramenta para identificar a condição de posicionamento relativo ferramenta/peça e obter informações que foram posteriormente usadas em um controlador PID, para realimentação de posição. Conclui com a avaliação e testes experimentais de deslocamento da ferramenta de corte, até 25 &#956m; com freqüência, até 10 Hz, realizados com o PFT projetado. / This work deals with the development of a tool post (PFT) for the micropositioning of a tool during ultraprecision machining in the nanometric range. Micropositioning employing piezoelectric actuators is defined. Precision engineering designs aspects applied to the development of the PFT are discussed. Control techniques such as PID and phase-lag compensator are addressed. A computer simulation for the verification of the vibrating modes of the PFT, with the simultaneous identification of the natural frequencies is carried out. An ideal model - all components will be manufactured and assembled - is presented. A control strategy based on the processing of signals acquired during the micropositioning of the tool to identify the positioning condition and to obtain information to be used by a PID controller is proposed. Experimental tests are performed with displacement of the tool, up to 25 &#956m, with frequency, up to 10 Hz.