25 resultados para measurement technology


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The starting point of this study is to direct more attention to the teacher and those entrepreneurship education practices taking place in formal school to find out solutions for more effective promotion of entrepreneurship education. For this objective, the strategy-level aims of entrepreneurship education need to be operationalised into measurable and understandable teacher-level practices. Furthermore, to enable the effective development of entrepreneurship education in basic and upper secondary level education, more knowledge is needed of the state of affairs of entrepreneurship education in teaching. The purpose of the study is to increase the level of understanding of teachers’ entrepreneurship education practices, and through this to develop entrepreneurship education. This study builds on the literature on entrepreneurship education and especially those elements referring to the aims, resources, benefits, methods, and practises of entrepreneurship education. The study comprises five articles highlighting teachers’ role in entrepreneurship education. In the first article the concept of entrepreneurship and the teachers role in reflection upon his/hers approaches to entrepreneurship education are considered. The second article provides a detailed analysis of the process of developing a measurement tool to depict the teachers’ activities in entrepreneurship education. The next three articles highlight the teachers’ role in directing the entrepreneurship education in basic and upper secondary level education. Furthermore, they analyse the relationship between the entrepreneurship education practises and the teachers’ background characteristics. The results of the study suggest a wide range of conclusions and implications. First, in spite of many outspoken aims connected to entrepreneurship education, teachers have not set any aims for themselves. Additionally, aims and results seem to mix. However, it is possible to develop teachers’ target orientation by supporting their reflection skills, and through measurement and evaluation increase their understanding of their own practices. Second, applying a participatory action process it is possible to operationalise teachers’entrepreneurship education practices. It is central to include the practitioners’ perspective in the development of measures to make sure that the concepts and aims of entrepreneurship education are understood. Third, teachers’ demographic or tenure-related background characteristics do not affect their entrepreneurship education practices, but their training related to entrepreneurship education, participation in different school-level or regional planning, and their own capabilities support entrepreneurship education. Fourth, a large number of methods are applied to entrepreneurship education, and the most often used methods were different kinds of discussions, which seem to be an easy, low-threshold way for teachers to include entrepreneurship education regularly in their teaching. Field trips to business enterprises or inviting entrepreneurs to present their work in schools are used fairly seldom. Interestingly, visits outside the school are more common than visitors invited to the school. In line, most of the entrepreneurship education practices take place in a classroom. Therefore it seems to be useful to create and encourage teachers towards more in-depth cooperation with companies (e.g. via joint projects) and to network systematically. Finally, there are plenty of resources available for entrepreneurship education, such as ready-made materials, external stakeholders, support organisations, and learning games, but teachers have utilized them only marginally.

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The most common reason for a low-voltage induction motor breakdown is a bearing failure. Along with the increasing popularity of modern frequency converters, bearing failures have become the most important motor fault type. Conditions in which bearing currents are likely to occur are generated as a side effect of fast du/dt switching transients. Once present, different types of bearing currents can accelerate the mechanical wear of bearings by causing deformation of metal parts in the bearing and degradation of the lubricating oil properties.The bearing current phenomena are well known, and several bearing current measurement and mitigation methods have been proposed. Nevertheless, in order to develop more feasible methods to measure and mitigate bearing currents, better knowledge of the phenomena is required. When mechanical wear is caused by bearing currents, the resulting aging impact has to be monitored and dealt with. Moreover, because of the stepwise aging mechanism, periodically executed condition monitoring measurements have been found ineffective. Thus, there is a need for feasible bearing current measurement methods that can be applied in parallel with the normal operation of series production drive systems. In order to reach the objectives of feasibility and applicability, nonintrusive measurement methods are preferred. In this doctoral dissertation, the characteristics and conditions of bearings that are related to the occurrence of different kinds of bearing currents are studied. Further, the study introduces some nonintrusive radio-frequency-signal-based approaches to detect and measure parameters that are associated with the accelerated bearing wear caused by bearing currents.

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The aim of the work presented in this study was to demonstrate the wide applicability of a single-label quenching resonance energy transfer (QRET) assay based on time-resolved lanthanide luminescence. QRET technology is proximity dependent method utilizing weak and unspecific interaction between soluble quencher molecule and lanthanide chelate. The interaction between quencher and chelate is lost when the ligand binds to its target molecule. The properties of QRET technology are especially useful in high throughput screening (HTS) assays. At the beginning of this study, only end-point type QRET technology was available. To enable efficient study of enzymatic reactions, the QRET technology was further developed to enable measurement of reaction kinetics. This was performed using proteindeoxyribonuclei acid (DNA) interaction as a first tool to monitor reaction kinetics. Later, the QRET was used to study nucleotide exchange reaction kinetics and mutation induced effects to the small GTPase activity. Small GTPases act as a molecular switch shifting between active GTP bound and inactive GDP bound conformation. The possibility of monitoring reaction kinetics using the QRET technology was evaluated using two homogeneous assays: a direct growth factor detection assay and a nucleotide exchange monitoring assay with small GTPases. To complete the list, a heterogeneous assay for monitoring GTP hydrolysis using small GTPases, was developed. All these small GTPase assays could be performed using nanomolar protein concentrations without GTPase pretreatment. The results from these studies demonstrated that QRET technology can be used to monitor reaction kinetics and further enable the possibility to use the same method for screening.

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In recent years, technological advancements in microelectronics and sensor technologies have revolutionized the field of electrical engineering. New manufacturing techniques have enabled a higher level of integration that has combined sensors and electronics into compact and inexpensive systems. Previously, the challenge in measurements was to understand the operation of the electronics and sensors, but this has now changed. Nowadays, the challenge in measurement instrumentation lies in mastering the whole system, not just the electronics. To address this issue, this doctoral dissertation studies whether it would be beneficial to consider a measurement system as a whole from the physical phenomena to the digital recording device, where each piece of the measurement system affects the system performance, rather than as a system consisting of small independent parts such as a sensor or an amplifier that could be designed separately. The objective of this doctoral dissertation is to describe in depth the development of the measurement system taking into account the challenges caused by the electrical and mechanical requirements and the measurement environment. The work is done as an empirical case study in two example applications that are both intended for scientific studies. The cases are a light sensitive biological sensor used in imaging and a gas electron multiplier detector for particle physics. The study showed that in these two cases there were a number of different parts of the measurement system that interacted with each other. Without considering these interactions, the reliability of the measurement may be compromised, which may lead to wrong conclusions about the measurement. For this reason it is beneficial to conceptualize the measurement system as a whole from the physical phenomena to the digital recording device where each piece of the measurement system affects the system performance. The results work as examples of how a measurement system can be successfully constructed to support a study of sensors and electronics.

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Unexpected changes in cash flow have started to occur more frequently after the financial crisis. The capital structures of companies have also changed, and financial flexibility as well as flexible asset management have therefore become more important. This thesis aims at presenting financial working capital management, a part of flexible asset management, as a possibility to gain financial flexibility and survive the changes. This thesis operates in the interface of corporate finance, strategic management and management accounting, and it has two main objectives: to examine financial working capital management and to develop measures of financial working capital. The research in this thesis has been conducted using archival research and design science. Qualitative comparative analysis and model building are used to formulate tools and strategies for financial working capital management. The tools are tested with simulations, case studies and statistical analysis. The empirical data is collected from companies listed in the Helsinki Stock Exchange. The results of this thesis indicate that there are several possible financial working capital management strategies. FOCAL matrix is created in the thesis to assist in the selection of a strategy. The results also imply that profitability can be improved by reducing financial working capital, which creates a need to change the financial working capital management strategy. Financial flow cycle, and its modification, is developed in this thesis to measure financial working capital. Financial working capital as a concept is presented in this thesis with an orientation towards the management view. New dimensions have also been produced to financial management and working capital management, while providing a holistic approach to financial flexibility. Financial working capital management strategies are presented to managers and practical tools are provided for decision-making.

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Tämä insinöörityö tehtiin Kuulonhuoltoliitto ry:n Esteetön kuuntelu -projektille. Työ käsittelee kuulolaitteen käyttäjän apuvälineenä käytettäviä induktiosilmukkajärjestelmiä. Induktiivisen äänensiirtojärjestelmän avulla huonokuuloinen saa kuunteluympäristöstään paremman signaali-kohinasuhteen ilman tilan kaikua ja taustahälyä. Tämä helpottaa kuuntelua esimerkiksi puhetilaisuuksissa. Työn tarkoituksena oli päivittää aiempia tutkimuksia kokoamalla uusin tietous induktiosilmukoiden tekniikasta. Kirjallisuustutkimuksen lisäksi kartoitettiin nykyinen silmukkavahvistinkanta haastattelemalla maahantuojia ja jälleenmyyjiä. Silmukkavahvistimien hintakartoituksen tarkoituksena oli rakentaa perusteet sopivan tehoisen ja hintaisen vahvistimen hankintaa varten suunniteltaessa induktiivisella äänensiirtojärjestelmällä varustettavia tiloja. Työ tarkastelee induktiivisen äänensiirtojärjestelmän ensisijaisen kohderyhmän, kuulokojeita käyttävien huonokuuloisten keskeisiä tarpeita ja heidän käyttämäänsä apuvälinetekniikkaa. Työ käy läpi audiotekniikan perusteita, sähkömagneettisen induktioilmiön, induktiivisen äänensiirtojärjestelmän rakenteen, sen ylikuulumisongelmat ja häiriötekijät sekä IEC:n 60118-4 edition 2.0 standardin CDV-luonnoksen mukaiset periaatteelliset asennusja mittausohjeet. IEC:n tuleva standardi tekee työstä ajankohtaisen. Työn tuloksena saatua tietoa voidaan käyttää Kuulonhuoltoliitto ry:n opas- ja tiedotusmateriaalin uudistamisessa, pohjana hyvän kuunteluympäristön malliratkaisujen ja esteettömyyskriteerien soveltamisessa. Työstä on hyötyä erityisesti Kuulonhuoltoliitto ry:n vapaaehtoiskartoittajille kuten myös kenelle tahansa aiheesta syvemmin kiinnostuneelle.

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This project focuses on studying and testing the benefits of the NX Remote Desktop technology in administrative use for Finnish Meteorological Institutes existing Linux Terminal Service Project environment. This was done due to the criticality of the system caused by growing number of users as the Linux Terminal Service Project system expands. Although many of the supporting tasks can be done via Secure Shell connection, testing graphical programs or desktop behaviour in such a way is impossible. At first basic technologies behind the NX Remote Desktop were studied, and after that started the testing of two possible programs, FreeNX and NoMachine NX server. Testing the functionality and bandwidth demands were first done in a closed local area network, and results were studied. The better candidate was then installed in a virtual server simulating actual Linux Terminal Service Project server at Finnish Meteorological Institute and connection from Internet was tested to see was there any problems with firewalls and security policies. The results are reported in this study. Studying and testing the two different candidates of NX Remote Desktop showed, that NoMachine NX Server provides better customer support and documentation. Security aspects of the Finnish Meteorological Institute had also to be considered, and since updates along with the new developing tools are announced in next version of the program, this version was the choice. Studies also show that even NoMachine promises a swift connection over an average of 20Kbit/s bandwidth, at least double of that is needed. This project gives an overview of available remote desktop products along their benefits. NX Remote Desktop technology is studied, and installation instructions are included. Testing is done in both, closed and the actual environment and problems and suggestions are studied and analyzed. The installation to the actual LTSP server is not yet made, but a virtual server is put up in the same place in the view of network topology. This ensures, that if the administrators are satisfied with the system, installation and setting up the system will go as described in this report.

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In this bachelor's thesis a relay card for capacitance measurements was designed, built and tested. The study was made for the research and development laboratory of VTI Technologies, which manufactures capacitive silicon micro electro mechanical accelerometers and pressure sensors. As the size of the sensors is decreasing the capacitance value of the sensors also decreases. The decreased capacitance causes a need for new and more accurate measurement systems. The technology used in the instrument measuring the capacitance dictates a framework how the relay card should be designed, thus the operating principle of the instrument must be known. To achieve accurate results the measurement instrument and its functions needed to be used correctly. The relay card was designed using printed circuit board design methods that minimize interference coupling to the measurement. The relay card that was designed in this study is modular. It consists of a separate CPU card, which was used to control the add-on cards connected to it. The CPU card was controlled from a computer through a serial bus. Two add-on cards for the CPU card were designed in this study. The first one was the measurement card, which could be used to measure 32 capacitive sensors. The second add-on card was the MUX card, which could be used to switch between two measurement cards. The capacitance measurements carried out through the MUX card and the measurement cards were characterized with a series of test measurements. The test measurement data was then analysed. The relay card design was confirmed to work and offer accurate measurement results up to a measurement frequency of 10 MHz. The length of the measurement cables limited the measurement frequency.

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Background Multiple sclerosis (MS) is a demyelinating disease of the central nervous system, which mainly affects young adults. In Finland, approximately 2500 out of 6000 MS patients have relapsing MS and are treated with disease modifying drugs (DMD): interferon- β (INF-β-1a or INF-β-1b) and glatiramer acetate (GA). Depending on the used IFN-β preparation, 2 % to 40 % of patients develop neutralizing antibodies (NAbs), which abolish the biological effects of IFN-β, leading to reduced clinical and MRI detected efficacy. According to the Finnish Current Care Guidelines and European Federation of Neurological Societis (EFNS) guidelines, it is suggested tomeasure the presence of NAbs during the first 24 months of IFN-β therapy. Aims The aim of this thesis was to measure the bioactivity of IFN-β therapy by focusing on the induction of MxA protein (myxovirus resistance protein A) and its correlation to neutralizing antibodies (NAb). A new MxA EIA assay was set up to offer an easier and rapid method for MxA protein detection in clinical practice. In addition, the tolerability and safety of GA were evaluated in patients who haddiscontinued IFN-β therapy due to side effects and lack of efficacy. Results NAbs developed towards the end of 12 months of treatment, and binding antibodies were detectable before or parallel with them. The titer of NAb correlated negatively with the amount of MxA protein and the mean values of preinjection MxA levels never returned to true baseline in NAb negative patients, but tended to drop in the NAb positive group. The test results between MxA EIA and flow cytometric analysis showed significant correlation. GA reduced the relapse rate and was a safe and well-tolerated therapy in IFN-β-intolerant MS patients. Conclusions NAbs inhibit the induction of MxA protein, which can be used as a surrogate marker of the bioactivity of IFN-β therapy. Compared to flow cytometricanalysis and NAb assay, MxA-EIA seemed to be a sensitive and more practical method in clinical use to measure the actual bioactivity of IFN-β treatment, which is of value also from a cost-effective perspective.