Structure-related magnetic fabric studies : implications for deformed and undeformed Precambrian rocks

The aim of this thesis research was to gain a better understanding of the emplacement of rapakivi granite intrusions, as well as the emplacement of gold-bearing hydrothermal fluids in structurally controlled mineralizations. Based on investigations of the magnetic fabric, the internal structures could be analysed and the intrusion mechanisms for rapakivi granite intrusions and respectively different deformation stages within gold-bearing shear and fault zones identified. Aeromagnetic images revealed circular structures within the rapakivi granite batholiths of Wiborg, Vehmaa and Åland. These circular structures represent intrusions that eventually build up these large batholiths. The rapakivi granite intrusions of Vehmaa, Ruotsinpyhtää within the Wiborg batholith and Saltvik intrusions within the Åland batholith all show bimodal magnetic susceptibilities with paramagnetic and ferromagnetic components. The distribution of the bimodality is related to different magma batches of the studied intrusions. The anisotropy of magnetic susceptibility (AMS) reveals internal structures that cannot be studied macroscopically or by microscope. The Ruotsinpyhtää and Vehmaa intrusions represent similar intrusion geometries, with gently to moderately outward dipping magnetic foliations. In the case of Vehmaa, the magnetic lineations are gently plunging and trend in the directions of the slightly elongated intrusion. The magnetic lineations represent magma flow. The shapes of the AMS ellipsoids are also more planar (oblate) in the central part of the intrusion, whereas they become more linear (prolate) near the margin. These AMS results, together with field observations, indicate that the main intrusion mechanism has involved the subsidence of older blocks with successive intrusion of fractionated magma during repeated cauldron subsidence. The Saltvik area within the Åland batholith consists of a number of smaller elliptical intrusions of different rapakivi types forming a multiple intrusive complex. The magnetic fabric shows a general westward dipping of the pyterlite and eastward dipping of the contiguous even-grained rapakivi granite, which indicates a central inflow of magma batches towards the east and west resulting from a laccolitic emplacement of magma batches, while the main mechanism for space creation was derived from subsidence. The magnetic fabric of structurally controlled gold potential shear and fault zones in Jokisivu, Satulinmäki and Koijärvi was investigated in order to describe the internal structures and define the deformation history and emplacement of hydrothermal fluids. A further aim of the research was to combine AMS studies with palaeomagnetic methods to constrain the timing for the shearing event relative to the precipitation of ferromagnetic minerals and gold. All of the studied formations are dominated by monoclinic pyrrhotite. The AMS directions generally follow the tectonic structures within the formations. However, internal variations in the AMS direction as well as the shapes of the AMS ellipsoids are observed within the shear zones. In Jokisivu and Satulinmäki in particular, the magnetic signatures of the shear zone core differ from the margins. Furthermore, the shape of the magnetic fabric in the shear zone core of Jokisivu is dominated by oblate shapes, whereas the margins exhibit prolate shapes. These variations indicate a later effect of the hydrothermal fluids on the general shear event. The palaeo-magnetic results reveal a deflection from the original Svecofennian age geomagnetic direction. These results, coupled with correlations between the orientation of the NRM vectors and the magnetic and rock fabrics, imply that the gold-rich hydrothermal fluids were emplaced pre/syntectonically during the late stages of the Svecofennian orogeny.

UMTS-radioverkon ja GSM-runkoverkon yhdistävän moduulin järjestelmätestaus

Tämän diplomityön aiheena oli tutkia ATM-moduulin järjestelmätestaustarpeita. ATM-moduuli on osa Nokian kolmannen generaation matkapuhelinverkkoarkkitehtuuria. Työ tehtiin Nokia Networks Oyj:lle MSC&HLR-tuotelinjan järjestelmätestausjaokselle. Työssä käsitellään aluksi GSM- ja UMTS-verkkojen arkkitehtuureja, protokollia ja toimintoja, sekä tutustutaan ATM-tekniikkaan, jota käytetään UMTS-liityntäverkon tiedonvälityksessä. Tämän jälkeen perehdytään ATM-moduulin rakenteeseen ja toimintoihin. Työssä perehdytään järjestelmätestauksen eri osa-alueisiin, niiden testilaitteille asettamiin vaatimuksiin sekä hahmotellaan järjestelmätestauksen päälinjoja.

Critical elements underpinning the emergence of the medical game ecosystem: gamifying traumatic brain injury rehabilitation in Finland

The healthcare sector is currently in the verge of a reform and thus, the medical game research provide an interesting area of research. The aim of this study is to explore the critical elements underpinning the emergence of the medical game ecosystem with three sub-objectives: (1) to seek who are the key actors involved in the medical game ecosystem and identify their needs, (2) to scrutinise what types of resources are required in medical game development and what types of relationships are needed to secure those resources, and (3) to identify the existing institutions (‘the rules of the game’) affecting the emergence of the medical game ecosystem. The theoretical background consists of service ecosystems literature. The empirical study conducted is based on the semi-structured theme interviews of 25 experts in three relevant fields: games and technology, health and funding. The data was analysed through a theoretical framework that was designed based upon service ecosystems literature. The study proposes that the key actors are divided into five groups: medical game companies, customers, funders, regulatory parties and complementors. Their needs are linked to improving patient motivation and enhancing the healthcare processes resulting in lower costs. Several types of resources, especially skills and knowledge, are required to create a medical game. To gain access to those resources, medical game companies need to build complex networks of relationships. Proficiency in managing those value networks is crucial. In addition, the company should take into account the underlying institutions in the healthcare sector affecting the medical game ecosystem. Three crucial institutions were identified: validation, lack of innovation supporting structures in healthcare and the rising consumerisation. Based on the findings, medical games cannot be made in isolation. A developmental trajectory model of the emerging medical game ecosystem was created based on the empirical data. The relevancy of relationships and resources is dependent on the trajectory that the medical game company at that time resides. Furthermore, creating an official and documented database for clinically valdated medical games was proposed to establish the medical game market and ensure an adequate status for the effective medical games. Finally, ecosystems approach provides interesting future opportunities for research on medical game ecosystems.

Information management in aircraft maintenance

Well managed information promotes competitive advantage and economic value for the company. The challenge is to use information effectively in complex networks. Decision making in network is complicated due to many independent sources of information. The aim of the present study was to identify and map the internal information flows and used information resourced by functions and roles, to make proposals to the case organization to improve the information management and to improve the situational awareness and process flows. In the present study, an inductive approach was applied, with the aim to find out gaps and bottlenecks of information flow of an aircraft maintenance organization and its network. The empirical part was conducted with observing the processes and with questionnaires. Theoretical part of this study consists on reviewing relevant literature on maintenance management in aviation and information management in aviation. Together with empirical evidence and the literature used in the study the gaps were found and suggestions for improvements were done. The outcome of this study contributes the organization in its bigger goal to improve the productivity. The information management of the network is one actor in the field and will pave the way to smoother operation and situational awareness. The lack of rules and requirements for information management and spreading is a challenge in information management. The excessive data overburden may cause problem in the actors’ situation-awareness due to non-availability of the right information.

Critical elements underpinning the emergence of the medical game ecosystem:gamifying traumatic brain injury rehabilitation in Finland

The healthcare sector is currently in the verge of a reform and thus, the medical game research provide an interesting area of research. The aim of this study is to explore the critical elements underpinning the emergence of the medical game ecosystem with three sub-objectives: (1) to seek who are the key actors involved in the medical game ecosystem and identify their needs, (2) to scrutinise what types of resources are required in medical game development and what types of relationships are needed to secure those resources, and (3) to identify the existing institutions (‘the rules of the game’) affecting the emergence of the medical game ecosystem. The theoretical background consists of service ecosystems literature. The empirical study conducted is based on the semi-structured theme interviews of 25 experts in three relevant fields: games and technology, health and funding. The data was analysed through a theoretical framework that was designed based upon service ecosystems literature. The study proposes that the key actors are divided into five groups: medical game companies, customers, funders, regulatory parties and complementors. Their needs are linked to improving patient motivation and enhancing the healthcare processes resulting in lower costs. Several types of resources, especially skills and knowledge, are required to create a medical game. To gain access to those resources, medical game companies need to build complex networks of relationships. Proficiency in managing those value networks is crucial. In addition, the company should take into account the underlying institutions in the healthcare sector affecting the medical game ecosystem. Three crucial institutions were identified: validation, lack of innovation supporting structures in healthcare and the rising consumerisation. Based on the findings, medical games cannot be made in isolation. A developmental trajectory model of the emerging medical game ecosystem was created based on the empirical data. The relevancy of relationships and resources is dependent on the trajectory that the medical game company at that time resides. Furthermore, creating an official and documented database for clinically validated medical games was proposed to establish the medical game market and ensure an adequate status for the effective medical games. Finally, ecosystems approach provides interesting future opportunities for research on medical game ecosystems

Design and implementation of FPGA-based LQ control of active magnetic bearings

The need for high performance, high precision, and energy saving in rotating machinery demands an alternative solution to traditional bearings. Because of the contactless operation principle, the rotating machines employing active magnetic bearings (AMBs) provide many advantages over the traditional ones. The advantages such as contamination-free operation, low maintenance costs, high rotational speeds, low parasitic losses, programmable stiffness and damping, and vibration insulation come at expense of high cost, and complex technical solution. All these properties make the use of AMBs appropriate primarily for specific and highly demanding applications. High performance and high precision control requires model-based control methods and accurate models of the flexible rotor. In turn, complex models lead to high-order controllers and feature considerable computational burden. Fortunately, in the last few years the advancements in signal processing devices provide new perspective on the real-time control of AMBs. The design and the real-time digital implementation of the high-order LQ controllers, which focus on fast execution times, are the subjects of this work. In particular, the control design and implementation in the field programmable gate array (FPGA) circuits are investigated. The optimal design is guided by the physical constraints of the system for selecting the optimal weighting matrices. The plant model is complemented by augmenting appropriate disturbance models. The compensation of the force-field nonlinearities is proposed for decreasing the uncertainty of the actuator. A disturbance-observer-based unbalance compensation for canceling the magnetic force vibrations or vibrations in the measured positions is presented. The theoretical studies are verified by the practical experiments utilizing a custom-built laboratory test rig. The test rig uses a prototyping control platform developed in the scope of this work. To sum up, the work makes a step in the direction of an embedded single-chip FPGA-based controller of AMBs.

Delivery system for location based information in wireless IP networks

Tämä työ esittelee uuden tarjota paikasta riippuvaa tietoa langattomien tietoverkkojen käyttäjille. Tieto välitetään jokaiselle käyttäjälle tietämättä mitään käyttäjän henkilöllisyydestä. Sovellustason protokollaksi valittiin HTTP, joka mahdollistaa tämän järjestelmän saattaa tietoa perille useimmille käyttäjille, jotka käyttävät hyvinkin erilaisia päätelaitteita. Tämä järjestelmä toimii sieppaavan www-liikenteen välityspalvelimen jatkeena. Erilaisten tietokantojen sisällä on perusteella järjestelmä päättää välitetäänkö tietoa vai ei. Järjestelmä sisältää myös yksinkertaisen ohjelmiston käyttäjien paikantamiseksi yksittäisen tukiaseman tarkkuudella. Vaikka esitetty ratkaisu tähtääkin paikkaan perustuvien mainosten tarjoamiseen, se on helposti muunnettavissa minkä tahansa tyyppisen tiedon välittämiseen käyttäjille.

Magnetic sputtering of complex oxides

HTSC materials are relevant in modern microelectronics, because of their transformation from the normal state to the superconducting. That is why the idea of producing HTSC in industrial amounts is actual nowadays. To decrease cost of their production it is important to use magnetron sputtering systems which give the best results for essential parameters. Modeling is the simplest and the fastest way to determine optimum sputtering condition. This thesis concentrates on determination the phases of the whole sputtering process and to find out basic factors of each phase using the modeling. It was find out, that the main factors which influence on the mode of occurrence of the initial stages are the current density of the magnetron discharge and the pressure of sputtering gas. With the modeling also velocity dependences were obtained for YBCO and SmFeAsO. These were compared and difference between them was examined. To support represented model comparison was made with experimental results. This showed that the model gives good results, very similar to the experimental ones. The results of this work were published in annual conference of the finnish physical society.

Broadband excitation in the system identification of active magnetic bearing rotor systems

One of the targets of the climate and energy package of the European Union is to increase the energy efficiency in order to achieve a 20 percent reduction in primary energy use compared with the projected level by 2020. The energy efficiency can be improved for example by increasing the rotational speed of large electrical drives, because this enables the elimination of gearboxes leading to a compact design with lower losses. The rotational speeds of traditional bearings, such as roller bearings, are limited by mechanical friction. Active magnetic bearings (AMBs), on the other hand, allow very high rotational speeds. Consequently, their use in large medium- and high-speed machines has rapidly increased. An active magnetic bearing rotor system is an inherently unstable, nonlinear multiple-input, multiple-output system. Model-based controller design of AMBs requires an accurate system model. Finite element modeling (FEM) together with the experimental modal analysis provides a very accurate model for the rotor, and a linearized model of the magneticactuators has proven to work well in normal conditions. However, the overall system may suffer from unmodeled dynamics, such as dynamics of foundation or shrink fits. This dynamics can be modeled by system identification. System identification can also be used for on-line diagnostics. In this study, broadband excitation signals are adopted to the identification of an active magnetic bearing rotor system. The broadband excitation enables faster frequency response function measurements when compared with the widely used stepped sine and swept sine excitations. Different broadband excitations are reviewed, and the random phase multisine excitation is chosen for further study. The measurement times using the multisine excitation and the stepped sine excitation are compared. An excitation signal design with an analysis of the harmonics produced by the nonlinear system is presented. The suitability of different frequency response function estimators for an AMB rotor system are also compared. Additionally, analytical modeling of an AMB rotor system, obtaining a parametric model from the nonparametric frequency response functions, and model updating are discussed in brief, as they are key elements in the modeling for a control design. Theoretical methods are tested with a laboratory test rig. The results conclude that an appropriately designed random phase multisine excitation is suitable for the identification of AMB rotor systems.

AMB system for high-speed motors using automatic commissioning

The general trend towards increasing e ciency and energy density drives the industry to high-speed technologies. Active Magnetic Bearings (AMBs) are one of the technologies that allow contactless support of a rotating body. Theoretically, there are no limitations on the rotational speed. The absence of friction, low maintenance cost, micrometer precision, and programmable sti ness have made AMBs a viable choice for highdemanding applications. Along with the advances in power electronics, such as signi cantly improved reliability and cost, AMB systems have gained a wide adoption in the industry. The AMB system is a complex, open-loop unstable system with multiple inputs and outputs. For normal operation, such a system requires a feedback control. To meet the high demands for performance and robustness, model-based control techniques should be applied. These techniques require an accurate plant model description and uncertainty estimations. The advanced control methods require more e ort at the commissioning stage. In this work, a methodology is developed for an automatic commissioning of a subcritical, rigid gas blower machine. The commissioning process includes open-loop tuning of separate parts such as sensors and actuators. The next step is to apply a system identi cation procedure to obtain a model for the controller synthesis. Finally, a robust model-based controller is synthesized and experimentally evaluated in the full operating range of the system. The commissioning procedure is developed by applying only the system components available and a priori knowledge without any additional hardware. Thus, the work provides an intelligent system with a self-diagnostics feature and an automatic commissioning.

One chip solution for low-cost active magnetic bearing system

In this work the implementation of the active magnetic bearing control system in a single FPGA is studied. Requirements for the full magnetic bearing control system are reviewed. Different control methods for active magnetic bearings are described shortly. Flux and the current base controllers are implemented in a FPGA. Suitability of the con-trollers for a low-cost magnetic bearing application is studied. Floating-point arithmetic’s are used in the controllers to ease designing burden and improve calculation precision. Per-formance of the flux controller is verified with simulations.

Chaotic Behaviour of Active Magnetic Bearing System by Time Series Analysis

Chaotic behaviour is one of the hardest problems that can happen in nonlinear dynamical systems with severe nonlinearities. It makes the system's responses unpredictable. It makes the system's responses to behave similar to noise. In some applications it should be avoided. One of the approaches to detect the chaotic behaviour is nding the Lyapunov exponent through examining the dynamical equation of the system. It needs a model of the system. The goal of this study is the diagnosis of chaotic behaviour by just exploring the data (signal) without using any dynamical model of the system. In this work two methods are tested on the time series data collected from AMB (Active Magnetic Bearing) system sensors. The rst method is used to nd the largest Lyapunov exponent by Rosenstein method. The second method is a 0-1 test for identifying chaotic behaviour. These two methods are used to detect if the data is chaotic. By using Rosenstein method it is needed to nd the minimum embedding dimension. To nd the minimum embedding dimension Cao method is used. Cao method does not give just the minimum embedding dimension, it also gives the order of the nonlinear dynamical equation of the system and also it shows how the system's signals are corrupted with noise. At the end of this research a test called runs test is introduced to show that the data is not excessively noisy.

Energy Management System for LVDC Island Networks

Recent developments in power electronics technology have made it possible to develop competitive and reliable low-voltage DC (LVDC) distribution networks. Further, islanded microgrids—isolated small-scale localized distribution networks— have been proposed to reliably supply power using distributed generations. However, islanded operations face many issues such as power quality, voltage regulation, network stability, and protection. In this thesis, an energy management system (EMS) that ensures efficient energy and power balancing and voltage regulation has been proposed for an LVDC island network utilizing solar panels for electricity production and lead-acid batteries for energy storage. The EMS uses the master/slave method with robust communication infrastructure to control the production, storage, and loads. The logical basis for the EMS operations has been established by proposing functionalities of the network components as well as by defining appropriate operation modes that encompass all situations. During loss-of-powersupply periods, load prioritizations and disconnections are employed to maintain the power supply to at least some loads. The proposed EMS ensures optimal energy balance in the network. A sizing method based on discrete-event simulations has also been proposed to obtain reliable capacities of the photovoltaic array and battery. In addition, an algorithm to determine the number of hours of electric power supply that can be guaranteed to the customers at any given location has been developed. The successful performances of all the proposed algorithms have been demonstrated by simulations.