Erkki Kurenniemen sähkösoittimet

Helsingin yliopiston "ääniteknillinen laboratorio" ja integroitu syntesoija ; Soittimia tilaustyönä ; Digelius Electronics Finland oy ja dimi-soittimet ; Kurenniemen soitinten toimintaperiaatteista ; Yhteenveto.

Rapid Scan Electron Paramagnetic Resonance (EPR) and Digital EPR Development

Rapid scan electron paramagnetic resonance (EPR) was developed in the Eaton laboratory at the University of Denver. Applications of rapid scan to wider spectra, such as for immobilized nitroxides, spin-labeled proteins, irradiated tooth and fingernail samples were demonstrated in this dissertation. The scan width has been increased from 55 G to 160 G. The signal to noise (S/N) improvement for slowly tumbling spin-labeled protein samples that is provided by rapid scan EPR will be highly advantageous for biophysical studies. With substantial improvement in S/N by rapid scan, the dose estimation for irradiated tooth enamels became more reliable than the traditional continuous wave (CW) EPR. An alternate approach of rapid scan, called field-stepped direct detection EPR, was developed to reconstruct wider EPR signals. A Mn2+ containing crystal was measured by field-stepped direct detection EPR, which had a spectrum more than 6000 G wide. Since the field-stepped direct detection extends the advantages of rapid scan to much wider scan ranges, this methodology has a great potential to replace the traditional CW EPR. With recent advances in digital electronics, a digital rapid scan spectrometer was built based on an arbitrary waveform generator (AWG), which can excite spins and detect EPR signals with a fully digital system. A near-baseband detection method was used to acquire the in-phase and quadrature signals in one physical channel. The signal was analyzed digitally to generate ideally orthogonal quadrature signals. A multiharmonic algorithm was developed that employed harmonics of the modulation frequencies acquired in the spectrometer transient mode. It was applied for signals with complicated lineshapes, and can simplify the selection of modulation amplitude. A digital saturation recovery system based on an AWG was built at X-band (9.6 GHz). To demonstrate performance of the system, the spin-lattice relaxation time of a fused quartz rod was measured at room temperature with fully digital excitation and detection.

Performance evaluation of the digital AM receiver /

Mode of access: Internet.

Eficiência energética e controlo de iluminação em edifícios

Dissertação para obtenção do grau de Mestre em Engenharia Electrotécnica Ramo de Energia

Sistema de Controlo Remoto de Luzes de Aeródromo

Este relatório apresenta o trabalho realizado no âmbito da unidade curricular de Dissertação do Mestrado em Engenharia Electrotécnica e de Computadores – área de especialização de Automação e Sistemas. O trabalho realizado consiste no desenvolvimento de um Sistema de Controlo Remoto de Luzes de Aeródromo (SCRLA) que pode ser aplicado em paralelo aos comandos locais de controlo das luzes de aproximação, pista ou circulação, entre outras, de uma infra-estrutura aeroportuária. O objectivo fundamental deste sistema consiste em permitir ao piloto de uma aeronave o acendimento das luzes do aeródromo desde a própria aeronave, recorrendo apenas ao equipamento de rádio VHF existente a bordo da mesma e que é normalmente usado para comunicações com os serviços de controlo de tráfego aéreo. Este sistema, em aeródromos com possível operação nocturna (e.g., heliportos de hospitais), permite uma redução dos custos associados a despesas com eventual pessoal técnico ou a redução da carga de trabalho neste, e uma diminuição do consumo de energia eléctrica, uma vez que as luzes apenas são acendidas quando necessário. Este sistema permite também reduzir a poluição luminosa no ambiente e contribui positivamente para a longevidade dos equipamentos luminosos. No desenvolvimento do sistema, foram adquiridos e/ou aplicados conhecimentos nas áreas de navegação aérea, infra-estruturas aeroportuárias, telecomunicações, normalização e estandardização, electrónicas analógica e digital, programação de baixo nível em microcontroladores, desenho e construção de circuitos impressos, desenho e construção mecânica.

Internal Combustion Engine's Throttle Control as a Motivational Theme for Teaching Microprocessors Systems Lab Classes

The increased fuel economy and driveability of modern internal combustion engine vehicles (ICEVs) are the result of the application of advanced digital electronics to control the operation of the internal combustion engine (ICE). Microprocessors (and micro controllers) play a key role in the engine control, by precisely controlling the amount of both air and fuel admitted into the cylinders. Air intake is controlled by utilizing a throttle valve equipped with a motor and gear mechanism as actuator, and a sensor enabling the measurement of the angular position of the blades. This paperwork presents a lab setup that allows students to control the throttle position using a microcontroller that runs a program developed by them. A commercial throttle body has been employed, whereas a power amplifier and a microcontroller board have been hand assembled to complete the experimental setup. This setup, while based in a high-tech, microprocessor-based solution for a real-world, engine operation optimization problem, has the potential to engage students around a hands-on multidisciplinary lab activity and ignite their interest in learning fundamental and advanced topics of microprocessors systems.

A methodology to analyze, design and implement very fast and robust controls of Buck-type converters

La electrónica digital moderna presenta un desafío a los diseñadores de sistemas de potencia. El creciente alto rendimiento de microprocesadores, FPGAs y ASICs necesitan sistemas de alimentación que cumplan con requirimientos dinámicos y estáticos muy estrictos. Específicamente, estas alimentaciones son convertidores DC-DC de baja tensión y alta corriente que necesitan ser diseñados para tener un pequeño rizado de tensión y una pequeña desviación de tensión de salida bajo transitorios de carga de una alta pendiente. Además, dependiendo de la aplicación, se necesita cumplir con otros requerimientos tal y como proveer a la carga con ”Escalado dinámico de tensión”, donde el convertidor necesitar cambiar su tensión de salida tan rápidamente posible sin sobreoscilaciones, o ”Posicionado Adaptativo de la Tensión” donde la tensión de salida se reduce ligeramente cuanto más grande sea la potencia de salida. Por supuesto, desde el punto de vista de la industria, las figuras de mérito de estos convertidores son el coste, la eficiencia y el tamaño/peso. Idealmente, la industria necesita un convertidor que es más barato, más eficiente, más pequeño y que aún así cumpla con los requerimienos dinámicos de la aplicación. En este contexto, varios enfoques para mejorar la figuras de mérito de estos convertidores se han seguido por la industria y la academia tales como mejorar la topología del convertidor, mejorar la tecnología de semiconducores y mejorar el control. En efecto, el control es una parte fundamental en estas aplicaciones ya que un control muy rápido hace que sea más fácil que una determinada topología cumpla con los estrictos requerimientos dinámicos y, consecuentemente, le da al diseñador un margen de libertar más amplio para mejorar el coste, la eficiencia y/o el tamaño del sistema de potencia. En esta tesis, se investiga cómo diseñar e implementar controles muy rápidos para el convertidor tipo Buck. En esta tesis se demuestra que medir la tensión de salida es todo lo que se necesita para lograr una respuesta casi óptima y se propone una guía de diseño unificada para controles que sólo miden la tensión de salida Luego, para asegurar robustez en controles muy rápidos, se proponen un modelado y un análisis de estabilidad muy precisos de convertidores DC-DC que tienen en cuenta circuitería para sensado y elementos parásitos críticos. También, usando este modelado, se propone una algoritmo de optimización que tiene en cuenta las tolerancias de los componentes y sensados distorsionados. Us ando este algoritmo, se comparan controles muy rápidos del estado del arte y su capacidad para lograr una rápida respuesta dinámica se posiciona según el condensador de salida utilizado. Además, se propone una técnica para mejorar la respuesta dinámica de los controladores. Todas las propuestas se han corroborado por extensas simulaciones y prototipos experimentales. Con todo, esta tesis sirve como una metodología para ingenieros para diseñar e implementar controles rápidos y robustos de convertidores tipo Buck. ABSTRACT Modern digital electronics present a challenge to designers of power systems. The increasingly high-performance of microprocessors, FPGAs (Field Programmable Gate Array) and ASICs (Application-Specific Integrated Circuit) require power supplies to comply with very demanding static and dynamic requirements. Specifically, these power supplies are low-voltage/high-current DC-DC converters that need to be designed to exhibit low voltage ripple and low voltage deviation under high slew-rate load transients. Additionally, depending on the application, other requirements need to be met such as to provide to the load ”Dynamic Voltage Scaling” (DVS), where the converter needs to change the output voltage as fast as possible without underdamping, or ”Adaptive Voltage Positioning” (AVP) where the output voltage is slightly reduced the greater the output power. Of course, from the point of view of the industry, the figures of merit of these converters are the cost, efficiency and size/weight. Ideally, the industry needs a converter that is cheaper, more efficient, smaller and that can still meet the dynamic requirements of the application. In this context, several approaches to improve the figures of merit of these power supplies are followed in the industry and academia such as improving the topology of the converter, improving the semiconductor technology and improving the control. Indeed, the control is a fundamental part in these applications as a very fast control makes it easier for the topology to comply with the strict dynamic requirements and, consequently, gives the designer a larger margin of freedom to improve the cost, efficiency and/or size of the power supply. In this thesis, how to design and implement very fast controls for the Buck converter is investigated. This thesis proves that sensing the output voltage is all that is needed to achieve an almost time-optimal response and a unified design guideline for controls that only sense the output voltage is proposed. Then, in order to assure robustness in very fast controls, a very accurate modeling and stability analysis of DC-DC converters is proposed that takes into account sensing networks and critical parasitic elements. Also, using this modeling approach, an optimization algorithm that takes into account tolerances of components and distorted measurements is proposed. With the use of the algorithm, very fast analog controls of the state-of-the-art are compared and their capabilities to achieve a fast dynamic response are positioned de pending on the output capacitor. Additionally, a technique to improve the dynamic response of controllers is also proposed. All the proposals are corroborated by extensive simulations and experimental prototypes. Overall, this thesis serves as a methodology for engineers to design and implement fast and robust controls for Buck-type converters.

Control point design using modular logic,

Mode of access: Internet.

Focus on Users – The National Digital Library of Finland

Heli Kautosen esitys Digital Humanities 2012 -konferenssissa Hampurissa 20.7.2012

The National Digital Library of Finland – Public Interface FINNA

Aki Lassilan esitys IFLA-konferenssissa Helsingissä 14.8.2012.

Digital Cultural Heritage at the National Library of Finland

Short presentation about how digital cultural heritage is created and collected by the National Library of Finland

The National Digital Library Finna Among Digital Research Infrastructures in Finland

Heli Kautosen esitys Epics, Digital Cultural Heritage and Vernacular Languages. Corpora and Databases in Oral Tradition Research -seminaarissa Helsingissä 2.3.2013.

Digital services development – cases of Finland and LIBER

The presentation of Kristiina Hormia-Poutanen in The National and University Library in Zagreb March 18, 2015.

Digital Transformation of Municipal Services in Finland

Digitalization has been widely adopted by private organizations of all sizes. As customers we are starting to expect a certain level of digital services from businesses and these expectations are evolving to consider the public sector services as well. Moreover, the Finnish municipalities are under pressure to cut costs and make their operation more efficient. This research aims in exploring the field of municipal digitalization in Finland with three main questions to answer: what are the motivations for municipalities for digital service transformation, what the main benefits of this transformation are and what are the challenges for the transformation. The research starts with examining the characteristics of municipal operation and reviewing some of the relevant digital service opportunities. In the empirical part of the research, 11 professionals related to the municipal field were interviewed using a semi-structured interview design. These interviewees were chosen from three important groups for the change: the service provider, municipal administration and municipal employees. The data gained from the interviews was first summarized according to the main topics chosen from the literature and then reflected on the digital services opportunities presented in the research. The motivations discovered in both the service provider and the city of Porvoo interviews were: tightening resources combined with increasing expectations, transparent structuring of information, supporting the shift into mobile and providing new channels for customers to participate. The benefits discovered in all groups were: efficiency, customer experience, transparent structuring of information, reducing manual input and responding to customer needs in service development. The challenges perceived by multiple groups were: change resistance, innovating new with no best practices and defining the scope and new operation model. The results of this research suggest that even with some challenges along the way, digitalization is a likely future for the Finnish public sector. The business case for the transformation is becoming increasingly evident on both municipal- and governmental levels.

Over the Air Download for Digital Television Receivers Upgrade

Over the air download is an important feature for terrestrial digital television systems. It provides a cheaper option for DTV receiver manufacturers to provide bug fixes and quality improvements to their products, allowing a shorter time to the market. This paper presents a mechanism proposal of an over the air download software update for the Brazilian system. This mechanism was specified considering the Brazilian DTV over the air download specifications, but it was extended considering efficiency, reliability and user transparency as requirements for software update. A proof of concept was implemented on a Linux based set-top box. The mechanism is divided into five main functional parts: download schedule, packets download, packets authentication, installation and error robustness. Some analyses were conducted upon the implementation considering the following criteria: download robustness and maximum downloading rate. (1)