19 resultados para Non-line-of-sight
em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland
Resumo:
Electric motors driven by adjustable-frequency converters may produce periodic excitation forces that can cause torque and speed ripple. Interaction with the driven mechanical system may cause undesirable vibrations that affect the system performance and lifetime. Direct drives in sensitive applications, such as elevators or paper machines, emphasize the importance of smooth torque production. This thesis analyses the non-idealities of frequencyconverters that produce speed and torque ripple in electric drives. The origin of low order harmonics in speed and torque is examined. It is shown how different current measurement error types affect the torque. As the application environment, direct torque control (DTC) method is applied to permanent magnet synchronous machines (PMSM). A simulation model to analyse the effect of the frequency converter non-idealities on the performance of the electric drives is created. Themodel enables to identify potential problems causing torque vibrations and possibly damaging oscillations in electrically driven machine systems. The model is capable of coupling with separate simulation software of complex mechanical loads. Furthermore, the simulation model of the frequency converter's control algorithm can be applied to control a real frequency converter. A commercial frequencyconverter with standard software, a permanent magnet axial flux synchronous motor and a DC motor as the load are used to detect the effect of current measurement errors on load torque. A method to reduce the speed and torque ripple by compensating the current measurement errors is introduced. The method is based on analysing the amplitude of a selected harmonic component of speed as a function oftime and selecting a suitable compensation alternative for the current error. The speed can be either measured or estimated, so the compensation method is applicable also for speed sensorless drives. The proposed compensation method is tested with a laboratory drive, which consists of commercial frequency converter hardware with self-made software and a prototype PMSM. The speed and torque rippleof the test drive are reduced by applying the compensation method. In addition to the direct torque controlled PMSM drives, the compensation method can also beapplied to other motor types and control methods.
Resumo:
In this dissertation, Active Galactic Nuclei (AGN) and their host galaxies are discussed. Together with transitional events, such as supernovae and gamma-ray bursts, AGN are the most energetic phenomena in the Universe. The dominant fraction of their luminosity originates from the center of a galaxy, where accreting gas falls into a supermassive black hole, converting gravitational energy to radiation. AGN have a wide range of observed properties: e.g. in their emission lines, radio emission, and variability. Most likely, these properties depend significantly on their orientation to our line-of-sight, and to unify AGN into physical classes it is crucial to observe their orientation-independent properties, such as the host galaxies. Furthermore, host galaxy studies are essential to understand the formation and co-evolution of galactic bulges and supermassive black holes. In this thesis, the main focus is on observationally characterizing AGN host galaxies using optical and near-infrared imaging and spectroscopy. BL Lac objects are a class of AGN characterized by rapidly variable and polarized continuum emission across the electromagnetic spectrum, and coredominated radio emission. The near-infrared properties of intermediate redshift BL Lac host galaxies are studied in Paper I. They are found to be large elliptical galaxies that are more luminous than their low redshift counterparts suggesting a strong luminosity evolution, and a contribution from a recent star formation episode. To analyze the stellar content of galaxies in more detail multicolor data, especially observations at blue wavelengths, are essential. In Paper III, optical - near-infrared colors and color gradients are derived for low redshift BL Lac host galaxies. They show bluer colors and steeper color gradients than inactive ellipticals which, most likely, are caused by a relatively young stellar population indicating a different evolutionary stage between AGN hosts and inactive ellipticals. In Paper II, near-infrared imaging of intermediate redshift radio-quiet quasar hosts is used to study their luminosity evolution. The hosts are large elliptical galaxies, but they are systematically fainter than the hosts of radio-loud quasars at similar redshifts, suggesting a link between the luminosity of the host galaxies and the radio properties of AGN. In Paper IV, the characteristics of near-infrared stellar absorption features of low redshift radio galaxies are compared with those of inactive early-type galaxies. The comparison suggests that early-type galaxies with AGN are in a different evolutionary stage than their inactive counterparts. Moreover, radio galaxies are found to contain stellar populations containing both old and intermediate age components.
Resumo:
Reaaliaikainen, ennakoiva kunnonvalvonta on erittäin tärkeä osa modernin tehtaan tai tuotantolinjan toimintaa. Diplomityön teettäjä haluaa edelleen kehittää akustiseen emissioon perustuvaa kunnonvalvonta järjestelmäänsä, jotta siitä olisi enemmän hyötyä asiakkaalle. Diplomityö sisältää johdannonakustiseen emissioon ja akustisiin emissio sensoreihin. Työn tavoitteena oli kehittää päätöksentekojärjestelmä, jota käytettäisiin työn teettäjän valmistamien sensoreiden antaman tiedon automatisoituun analysointiin. Työssä on vertailtu kolmea eri ohjelmistotoimittajaa ja heidän ohjelmiaan, ja tehty ehdotus hankittavasta ohjelmistosta. Lisäksi työssä on kehitetty ohjeita, joiden avulla ohjelmisto ohjelmoidaan tuottamaan reaaliaikaista tietoa ja huolto-ohjeita sen käyttäjille. Lisäksi työssä annetaan ehdotuksia kunnonvalvonta- ja päätöksentekojärjestelmän edelleen kehittämiseen.
Resumo:
Tämän kannattavuustutkimuksen lähtökohtana oli se, että Yhtyneet Sahat Oy:n Kaukaan sahalla ja Luumäen jatkojalostuslaitoksella haluttiin selvittää pellettitehtaan kannattavuus nykyisessä markkinatilanteessa. Tämä työon luonteeltaan teknis-taloudellinen selvitys eli ns. feasibility study. Pelletöintiprosessi on tekniikaltaan yksinkertainen eikä edellytä korkea teknologian laitteita. Toimiala on maailmanlaajuisesti varsin uusi. Suomessa pellettimarkkinat ovat vielä pienet ja kehittymättömät, mutta kasvua on viime vuosina tapahtunut. Valtaosa kotimaan tuotannosta menee vientiin. Investoinnin laskentaprosessissa saadut tuotannon alkuarvot sekä kustannusrakenteen määrittelyt ovat perustana varsinaisille kannattavuuslaskelmille. Laskelmista on selvitetty investointeihin liittyvät yleisimmät taloudelliset tunnusluvut ja herkimpiä muuttujia on tutkittu ja pohdittu herkkyysanalyysiä apuna käyttäen.
Resumo:
Tämän tutkimuksen aiheena on tilintarkastuksen historiallinen kehittyminen Suomessa runsaan sadan vuoden aikana. Tutkimuksen tavoitteena on analysoida osakeyhtiön tilintarkastuksen kehitystä ja yhdistää vuosisadan kehityspiirteet tilintarkastuksen kokonaiskuvaksi. Tutkittava periodi alkaa 1800-luvun lopulta ja päättyy 2000-luvun taitteeseen. Tutkimuksessa tarkastellaan suomalaista tilintarkastusinstituutiota, joka jaetaan kolmeen osaan: tilintarkastusta säätelevään normistoon (normit), tilintarkastajajärjestelmään (toimijat) ja tilintarkastuksen sisältöön (tehtävät). Tutkimuksessa tavoitellaan vastauksia kysymyksiin: mitä tarkastettiin, milloin tarkastettiin, kuka tarkasti ja miten tarkastettiin eri aikakausina? Tutkimus perustuu historialliseen lähdeaineistoon, jonka muodostavat tutkimusajanjakson lainsäädäntö, lainvalmisteluasiakirjat, viranomaisten ohjeet ja päätökset, alan järjestöjen suositukset, ammattilehtien artikkelit sekä laskentatoimen ja tilintarkastuksen ammattikirjallisuus. Metodologisesti tutkimus on teoreettinen, kvalitatiivinen historiantutkimus, jossa lähdeaineistoa käsitellään lähdekriittisesti ja osittain sisältöanalyysin keinoin. Tilintarkastusta säätelevässä normistossa keskeisiä lakeja ovat olleet osakeyhtiölaki, kirjanpitolaki ja tilintarkastuslaki. Lakisääteinen tilintarkastus alkoi vuoden 1895 osakeyhtiölaista, joka uudistui vuonna 1978 ja jälleen vuonna 1997. Kirjanpitolainsäädäntö on uudistunut viidesti: 1925 ja 1928, 1945, 1973, 1993 sekä 1997. Vuoden 1994 tilintarkastuslakiin koottiin tilintarkastuksen säädökset useista laeista. Muita normistoja ovat olleet EY:n direktiivit, Kilan ohjeet, KHT-yhdistyksen suositukset, Keskuskauppakamarin säännökset ja viimeisimpinä IAS- ja ISA-standardit. Ammattimainen tilintarkastajajärjestelmä saatiin maahamme kauppiaskokousten ansiosta. Ammattimaisena tilintarkastuksen toimijana aloitti Suomen Tilintarkastajainyhdistys vuonna 1911, ja sen toimintaa jatkoi KHT-yhdistys vuodesta 1925 alkaen. Tilintarkastajien auktorisointi siirtyi Keskuskauppakamarille vuonna 1924. HTM-tilintarkastajat ovat olleet alalla vuodesta 1950 lähtien. Kauppakamarijärjestö on toiminut hyväksyttyjen tilintarkastajien valvojana koko ammattimaisen tilintarkastustoiminnan ajan. Valtion valvontaa suorittaa VALA (Valtion tilintarkastuslautakunta). Koko tutkittavan periodin ajan auktorisoitujen tilintarkastajien rinnalla osakeyhtiöiden tarkastajina ovat toimineet myös maallikot.Tilintarkastuksen tehtäviin kuului vuoden 1895 osakeyhtiölain mukaan hallinnon ja tilien tarkastus. Myöhemmin sisältö täsmentyi tilinpäätöksen, kirjanpidon ja hallinnon tarkastukseksi. Tutkimusajanjakson alussa tilintarkastus oli manuaalista kaikkien tositteiden prikkausta ja virheiden etsimistä. Myöhemmin tarkastus muuttui pistokokeiksi. Kertatarkastuksesta siirryttiin jatkuvaan valvontatarkastukseen 1900-luvun alkupuolella. Dokumentoinnista ja työpapereista alkaa olla havaintoja 1930-luvulta lähtien. Atk-tarkastus yleistyi 1970- ja 1980-luvuilla, jolloin myös riskianalyyseihin alettiin kiinnittää huomiota. Hallinnon tarkastuksen merkitys on kasvanut kaiken aikaa. Tilintarkastuskertomukset olivat tutkimusajanjakson alussa vapaamuotoisia ja sisällöltään ilmaisurikkaita ja kuvailevia. Kertomus muuttui julkiseksi vuoden 1978 osakeyhtiölain myötä. Myöhemmin KHT-yhdistyksen vakiokertomusmallit yhdenmukaistivat ja pelkistivät raportointia. Tutkimuksen perusteella tilintarkastuksen historia voidaan jakaa kolmeen kauteen, jotka ovat tilintarkastusinstituution rakentumisen kausi (1895 - 1950), vakiintumisen kausi (1951 - 1985) ja kansainvälistymisen ja julkisuuden kausi (1986 alkaen). Tutkimusajanjakson jokaisella vuosikymmenellä keskusteltiin jatkuvasti tilintarkastajien riittävyydestä, alalle pääsyn ja tutkintojen vaikeudesta, tilintarkastajien ammattitaidon tasosta,hallinnon tarkastuksen sisällöstä, tilintarkastuskertomuksesta sekä maallikkotarkastajien asemasta. 1990-luvun keskeisimmät keskusteluaiheet olivat konsultointi, riippumattomuus, odotuskuilu sekä tilintarkastuksen taso ja laadunvalvonta. Analysoitaessa tilintarkastuksen muutoksia runsaan sadan vuoden ajalta voidaan todeta, että tilintarkastuksen ydintehtävät eivät juurikaan ole muuttuneet vuosikymmenien kuluessa. Osakeyhtiön tilintarkastus on edelleenkin laillisuustarkastusta. Sen tarkoituksena on yhä kirjanpidon, tilinpäätöksen ja hallinnon tarkastus. Tilintarkastajat valvovat osakkeenomistajien etua ja raportoivat heille tarkastuksen tuloksista. Tilintarkastuksen ulkoinen maailma sen sijaan on muuttunut vuosikymmenten saatossa. Kansainvälistyminen on lisännyt säännösten määrää, odotuksia ja vaatimuksia on nykyisin enemmän, uusi tekniikka mahdollistaa nopean tiedonkulun ja valvonta on lisääntynyt nykypäivää kohti tultaessa. Tilintarkastajan pätevyys perustuu nykyään tietotekniikan, tietojärjestelmien ja yrityksen toimialantuntemukseen. Runsaan sadan vuoden takaisen lain vaarinpitovaatimuksesta on tultu virtuaaliaikaiseen maailmaan!
Resumo:
In a centrifugal compressor the flow around the diffuser is collected and led to the pipe system by a spiral-shaped volute. In this study a single-stage centrifugal compressor with three different volutes is investigated. The compressorwas first equipped with the original volute, the cross-section of which was a combination of a rectangle and semi-circle. Next a new volute with a fully circular cross-section was designed and manufactured. Finally, the circular volute wasmodified by rounding the tongue and smoothing the tongue area. The overall performance of the compressor as well as the static pressure distribution after the impeller and on the volute surface were measured. The flow entering the volute was measured using a three-hole Cobra-probe, and flow visualisations were carriedout in the exit cone of the volute. In addition, the radial force acting on theimpeller was measured using magnetic bearings. The complete compressor with thecircular volute (inlet pipe, full impeller, diffuser, volute and outlet pipe) was also modelled using computational fluid dynamics (CFD). A fully 3-D viscous flow was solved using a Navier-Stokes solver, Finflo, developed at Helsinki University of Technology. Chien's k-e model was used to take account of the turbulence. The differences observed in the performance of the different volutes were quite small. The biggest differences were at low speeds and high volume flows,i.e. when the flow entered the volute most radially. In this operating regime the efficiency of the compressor with the modified circular volute was about two percentage points higher than with the other volutes. Also, according to the Cobra-probe measurements and flow visualisations, the modified circular volute performed better than the other volutes in this operating area. The circumferential static pressure distribution in the volute showed increases at low flow, constant distribution at the design flow and decrease at high flow. The non-uniform static pressure distribution of the volute was transmitted backwards across the vaneless diffuser and observed at the impeller exit. At low volume flow a strong two-wave pattern developed into the static pressure distribution at the impeller exit due to the response of the impeller to the non-uniformity of pressure. The radial force of the impeller was the greatest at the choke limit, the smallest atthe design flow, and moderate at low flow. At low flow the force increase was quite mild, whereas the increase at high flow was rapid. Thus, the non-uniformityof pressure and the force related to it are strong especially at high flow. Theforce caused by the modified circular volute was weaker at choke and more symmetric as a function of the volume flow than the force caused by the other volutes.
Resumo:
Previous studies have demonstrated that clinical pulpal pain can induce the expression of pro-inflammatory neuropeptides in the adjacent gingival crevice fluid (GCF). Vasoactive agents such as substance P (SP) are known to contribute to the inflammatory type of pain and are associated with increased blood flow. More recent animal studies have shown that application of capsaicin on alveolar mucosa provokes pain and neurogenic vasodilatation in the adjacent gingiva. Pain-associated inflammatory reactions may initiate expression of several pro- and anti-inflammatory mediators. Collagenase-2 (MMP-8) has been considered to be the major destructive protease, especially in the periodontitis-affected gingival crevice fluid (GCF). MMP-8 originates mostly from neutrophil leukocytes, the first line of defence cells that exist abundantly in GCF, especially in inflammation. With this background, we wished to clarify the spatial extensions and differences between tooth-pain stimulation and capsaicin-induced neurogenic vasodilatation in human gingiva. Experiments were carried out to study whether tooth stimulation and capsaicin stimulation of alveolar mucosa would induce changes in GCF MMP-8 levels and whether tooth stimulation would release neuropeptide SP in GCF. The experiments were carried out on healthy human volunteers. During the experiments, moderate and high intensity painful tooth stimulation was performed by a constant current tooth stimulator. Moderate tooth stimulation activates A-delta fibres, while high stimulation also activates C-fibres. Painful stimulation of the gingiva was achieved by topical application of capsaicin-moistened filter paper on the mucosal surface. Capsaicin is known to activate selectively nociceptive C-fibres of stimulated tissue. Pain-evoked vasoactive changes in gingivomucosal tissues were mapped by laser Doppler imaging (LDI), which is a sophisticated and non-invasive method for studying e.g. spatial and temporal characteristics of pain- and inflammation-evoked blood flow changes in gingivomucosal tissues. Pain-evoked release of MMP-8 in GCF samples was studied by immunofluorometric assay (IFMA) and Western immunoblotting. The SP levels in GCF were analysed by Enzyme immunoassay (EIA). During the experiments, subjective stimulus-evoked pain responses were determined by a visual analogue pain scale. Unilateral stimulation of alveolar mucosa and attached gingiva by capsaicin evoked a distinct neurogenic vasodilatation in the ipsilateral gingiva, which attenuated rapidly at the midline. Capsaicin stimulation of alveolar mucosa provoked clear inflammatory reactions. In contrast to capsaicin stimuli, tooth stimulation produced symmetrical vasodilatations bilaterally in the gingiva. The ipsilateral responses were significantly smaller during tooth stimulation than during capsaicin stimuli. The current finding – that tooth stimulation evokes bilateral vasodilatation while capsaicin stimulation of the gingiva mainly produces unilateral vasodilatation – emphasises the usefulness of LDI in clarifying spatial features of neurogenic vasoactive changes in the intra-oral tissues. Capsaicin stimulation of the alveolar mucosa induced significant elevations in MMP-8 levels and activation in GCF of the adjacent teeth. During the experiments, no marked changes occurred in MMP-8 levels in the GCF of distantly located teeth. Painful stimulation of the upper incisor provoked elevations in GCF MMP-8 and SP levels of the stimulated tooth. The GCF MMP-8 and SP levels of the non-stimulated teeth were not changed. These results suggest that capsaicin-induced inflammatory reactions in gingivomucosal tissues do not cross the midline in the anterior maxilla. The enhanced reaction found during stimulation of alveolar mucosa indicates that alveolar mucosa is more sensitive to chemical irritants than the attached gingiva. Analysis of these data suggests that capsaicin-evoked neurogenic inflammation in the gingiva can trigger the expression and activation of MMP-8 in GCF of the adjacent teeth. In this study, it is concluded that experimental tooth pain at C-fibre intensity can induce local elevations in MMP-8 and SP levels in GCF. Depending on the role of MMP-8 in inflammation, in addition to surrogated tissue destruction, the elevated MMP-8 in GCF may also reflect accelerated local defensive and anti-inflammatory reactions.
Resumo:
Electricity spot prices have always been a demanding data set for time series analysis, mostly because of the non-storability of electricity. This feature, making electric power unlike the other commodities, causes outstanding price spikes. Moreover, the last several years in financial world seem to show that ’spiky’ behaviour of time series is no longer an exception, but rather a regular phenomenon. The purpose of this paper is to seek patterns and relations within electricity price outliers and verify how they affect the overall statistics of the data. For the study techniques like classical Box-Jenkins approach, series DFT smoothing and GARCH models are used. The results obtained for two geographically different price series show that patterns in outliers’ occurrence are not straightforward. Additionally, there seems to be no rule that would predict the appearance of a spike from volatility, while the reverse effect is quite prominent. It is concluded that spikes cannot be predicted based only on the price series; probably some geographical and meteorological variables need to be included in modeling.
Resumo:
IT outsourcing refers to the way companies focus on their core competencies and buy the supporting functions from other companies specialized in that area. Service is the total outcome of numerous of activities by employees and other resources to provide solutions to customers' problems. Outsourcing and service business have their unique characteristics. Service Level Agreements quantify the minimum acceptable service to the user. The service quality has to be objectively quantified so that its achievement or non-achievement of it can be monitored. Usually offshoring refers to the transferring of tasks to low-cost nations. Offshoring presents a lot of challenges that require special attention and they need to be assessed thoroughly. IT Infrastructure management refers to installation and basic usability assistance of operating systems, network and server tools and utilities. ITIL defines the industry best practices for organizing IT processes. This thesis did an analysis of server operations service and the customers’ perception of the quality of daily operations. The agreed workflows and processes should be followed better. Service providers’ processes are thoroughly defined but both the customer and the service provider might disobey them. Service provider should review the workflows regarding customer functions. Customer facing functions require persistent skill development, as they communicate the quality to the customer. Service provider needs to provide better organized communication and knowledge exchange methods between the specialists in different geographical locations.
Resumo:
In this Thesis I discuss the exact dynamics of simple non-Markovian systems. I focus on fundamental questions at the core of non-Markovian theory and investigate the dynamics of quantum correlations under non-Markovian decoherence. In the first context I present the connection between two different non-Markovian approaches, and compare two distinct definitions of non-Markovianity. The general aim is to characterize in exemplary cases which part of the environment is responsible for the feedback of information typical of non- Markovian dynamics. I also show how such a feedback of information is not always described by certain types of master equations commonly used to tackle non-Markovian dynamics. In the second context I characterize the dynamics of two qubits in a common non-Markovian reservoir, and introduce a new dynamical effect in a wellknown model, i.e., two qubits under depolarizing channels. In the first model the exact solution of the dynamics is found, and the entanglement behavior is extensively studied. The non-Markovianity of the reservoir and reservoirmediated-interaction between the qubits cause non-trivial dynamical features. The dynamical interplay between different types of correlations is also investigated. In the second model the study of quantum and classical correlations demonstrates the existence of a new effect: the sudden transition between classical and quantum decoherence. This phenomenon involves the complete preservation of the initial quantum correlations for long intervals of time of the order of the relaxation time of the system.
Resumo:
The aim of the present dissertation is to investigate the marketing culture of research libraries in Finland and to understand the awareness of the knowledge base of library management concerning modern marketing theories and practices. The study was based onthe notion that a leader in an organisation can have large impact on its culture. Therefore, it was considered important to learn about the market orientation that initiates at the top management and flows throughout the whole organisationthus resulting in a particular kind of library culture. The study attempts to examine the marketing culture of libraries by analysing the marketing attitudes, knowledge (underlying beliefs, values and assumptions), behaviour (market orientation), operational policies and activities, and their service performance (customer satisfaction). The research was based on the assumption that if the top management of libraries has market oriented behaviour, then their marketing attitudes, knowledge, operational policies and activities and service performance should also be in accordance. The dissertation attempts to connect all these theoretical threads of marketing culture. It investigates thirty three academic and special libraries in the south of Finland. The library director and three to ten customers from each library participated as respondents in this study. An integrated methodological approach of qualitative as well as quantitative methods was used to gain knowledge on the pertinent issues lying behind the marketing culture of research libraries. The analysis of the whole dissertation reveals that the concept of marketing has very varied status in the Finnish research libraries. Based on the entire findings, three kinds of marketing cultures were emerged: the strong- the high fliers; the medium- the brisk runners; and the weak- the slow walkers. The high fliers appeared to be modern marketing believers as their marketing approach was customer oriented and found to be closer to the emerging notions of contemporary relational marketing. The brisk runners were found to be traditional marketing advocates as their marketing approach is more `library centred¿than customer defined and thus is in line of `product orientation¿ i.e. traditional marketing. `Let the interested customers come to the library¿ was appeared to be the hallmark of the slow walkers. Application of conscious market orientation is not reflected in the library activities of the slow walkers. Instead their values, ideology and approach to serving the library customers is more in tuneof `usual service oriented Finnish way¿. The implication of the research is that it pays to be market oriented which results in higher customer satisfaction oflibraries. Moreover, it is emphasised that the traditional user based service philosophy of Finnish research libraries should not be abandoned but it needs to be further developed by building a relational based marketing system which will help the libraries to become more efficient and effective from the customers¿ viewpoint. The contribution of the dissertation lies in the framework showing the linkages between the critical components of the marketing culture of a library: antecedents, market orientation, facilitators and consequences. The dissertationdelineates the significant underlying dimensions of market-oriented behaviour of libraries which are namely customer philosophy, inter-functional coordination,strategic orientation, responsiveness, pricing orientation and competition orientation. The dissertation also showed the extent to which marketing attitudes, behaviour, knowledge were related and impact of market orientation on the serviceperformance of libraries. A strong positive association was found to exist between market orientation and marketing attitudes and knowledge. Moreover, it also shows that a higher market orientation is positively connected with the service performance of libraries, the ultimate result being higher customer satisfaction. The analysis shows that a genuine marketing culture represents a synthesis of certain marketing attitudes, knowledge and of selective practices. This finding is particularly significant in the sense that it manifests that marketing culture consists of a certain sets of beliefs and knowledge (which form a specific attitude towards marketing) and implementation of a certain set of activities that actually materialize the attitude of marketing into practice (market orientation) leading to superior service performance of libraries.
Resumo:
The focus of this study is to examine the role of police and immigrants’ relations, as less is known about this process in the country. The studies were approached in two different ways. Firstly, an attempt was made to examine how immigrants view their encounters with the police. Secondly, the studies explored how aware the police are of immigrants’ experiences in their various encounters and interactions on the street level. An ancillary aim of the studies is to clarify, analyse and discuss how prejudice and stereotypes can be tackled, thereby contributing to the general debate about racism and discrimination for better ethnic relations in the country. The data in which this analysis was based is on a group of adults (n=88) from the total of 120 Africans questioned for the entire study (n=45) police cadets and (n=6) serving police officers from Turku. The present thesis is a compilation of five articles. A summary of each article findings follows, as the same data was used in all five studies. In the first study, a theoretical model was developed to examine the perceived knowledge of bias by immigrants resulting from race, culture and belief. This was also an attempt to explore whether this knowledge was predetermined in my attempt to classify and discuss as well as analyse the factors that may be influencing immigrants’ allegations of unfair treatment by the police in Turku. The main finding shows that in the first paper there was ignorance and naivety on the part of the police in their attitudes towards the African immigrant’s prior experiences with the police, and this may probably have resulted from stereotypes or their lack of experience as well as prior training with immigrants where these kinds of experience are rampant in the country (Egharevba, 2003 and 2004a). In exploring what leads to stereotypes, a working definition is the assumption that is prevalent among some segments of the population, including the police, that Finland is a homogenous country by employing certain conducts and behaviour towards ethnic and immigrant groups in the country. This to my understanding is stereotype. Historically this was true, but today the social topography of the country is changing and becoming even more complex. It is true that, on linguistic grounds, the country is multilingual, as there are a few recognised national minority languages (Swedish, Sami and Russian) as well as a number of immigrant languages including English. Apparently it is vital for the police to have a line of communication open when addressing the problem associated with immigrants in the country. The second paper moved a step further by examining African immigrants’ understanding of human rights as well as what human rights violation means or entails in their views as a result of their experiences with the police, both in Finland and in their country of origin. This approach became essential during the course of the study, especially when the participants were completing the questionnaire (N=88), where volunteers were solicited for a later date for an in-depth interview with the author. Many of the respondents came from countries where human rights are not well protected and seldom discussed publicly, therefore understanding their views on the subject can help to explain why some of the immigrants are sceptical about coming forward to report cases of batteries and assaults to the police, or even their experiences of being monitored in shopping malls in their new home and the reason behind their low level of trust in public authorities in Finland. The study showed that knowledge of human rights is notably low among some of the participants. The study also found that female respondents were less aware of human rights when compared with their male counterparts. This has resulted in some of the male participants focussing more on their traditional ways of thinking by not realising that they are in a new country where there is equality in sexes and lack of respect on gender terms is not condoned. The third paper focussed on the respondents’ experiences with the police in Turku and tried to explore police attitudes towards African immigrant clients, in addition to the role stereotype plays in police views of different cultures and how these views have impacted on immigrants’ views of discriminatory policing in Turku. The data is the same throughout the entire studies (n=88), except that some few participants were interviewed for the third paper thirty-five persons. The results showed that there is some bias in mass-media reports on the immigrants’ issues, due to selective portrayal of biases without much investigation being carried out before jumping to conclusions, especially when the issues at stake involve an immigrant (Egharevba, 2005a; Egharevba, 2004a and 2004b). In this vein, there was an allegation that the police are even biased while investigating cases of theft, especially if the stolen property is owned by an immigrant (Egharevba, 2006a, Egharevba, 2006b). One vital observation from the respondents’ various comments was that race has meaning in their encounters and interaction with the police in the country. This result led the author to conclude that the relation between the police and immigrants is still a challenge, as there is rampant fear and distrust towards the police by some segments of the participating respondents in the study. In the fourth paper the focus was on examining the respondents’ view of the police, with special emphasis on race and culture as well as the respondents’ perspective on police behaviour in Turku. This is because race, as it was relayed to me in the study, is a significant predictor of police perception (Egharevba, 2005a; Egharevba and Hannikianen, 2005). It is a known scientific fact that inter-group racial attitudes are the representation of group competition and perceived threat to power and status (Group-position theory). According to Blumer (1958) a sense of group threat is an essential element for the emergence of racial prejudice. Consequently, it was essential that we explored the existing relationship between the respondents and the police in order to have an understanding of this concept. The result indicates some local and international contextual issues and assumptions that were of importance tackling prejudice and discrimination as it exists within the police in the country. Moreover, we have to also remember that, for years, many of these African immigrants have been on the receiving end of unjust law enforcement in their various countries of origin, which has resulted in many of them feeling inferior and distrustful of the police even in their own country of origin. While discussing the issues of cultural difference and how it affects policing, we must also keep in mind the socio-cultural background of the participants, their level of language proficiency and educational background. The research data analysed in this study also confirmed the difficulties associated with cultural misunderstandings in interpreting issues and how these misunderstandings have affected police and immigrant relations in Finland. Finally, the fifth paper focussed on cadets’ attitudes towards African immigrants as well as serving police officers’ interaction with African clients. Secondly, the police level of awareness of African immigrants’ distrustfulness of their profession was unclear. For this reason, my questions in this fifth study examined the experiences and attitudes of police cadets and serving police officers as well as those of African immigrants in understanding how to improve this relationship in the country. The data was based on (n=88) immigrant participants, (n=45) police cadets and 6 serving police officers from the Turku police department. The result suggests that there is distrust of the police in the respondents’ interaction; this tends to have galvanised a heightened tension resulting from the lack of language proficiency (Egharevba and White, 2007; Egharevba and Hannikainen, 2005, and Egharevba, 2006b) The result also shows that the allegation of immigrants as being belittled by the police stems from the misconceptions of both parties as well as the notion of stop and search by the police in Turku. All these factors were observed to have contributed to the alleged police evasiveness and the lack of regular contact between the respondents and the police in their dealings. In other words, the police have only had job-related contact with many of the participants in the present study. The results also demonstrated the complexities caused by the low level of education among some of the African immigrants in their understanding about the Finnish culture, norms and values in the country. Thus, the framework constructed in these studies embodies diversity in national culture as well as the need for a further research study with a greater number of respondents (both from the police and immigrant/majority groups), in order to explore the different role cultures play in immigrant and majority citizens’ understanding of police work.
Resumo:
Ruostumattomien terästen hinta on kasvanut maailman laajuisen kysynnän kasvun seurauksena. Samoin on käynyt myös ruostumattomien terästen valmistukseen käytettävien seosaineiden hinnalle. Terästen valmistajat ovatkin kehittäneet lean duplex teräksiä vastatakseen hintatietoisten markkinoiden kysyntään. Näissä lean duplex teräksissä kalliita seosaineita kuten nikkeliä ja molybdeenia on korvattu typellä ja mangaanilla. Houkutteleviksi vaihtoehdoiksi perinteisille ruostumattomille teräksille lean duplex laadut tekee myös niiden hyvät lujuus- ja korroosio-ominaisuudet. Kirjallisuus osio esittelee lasereiden toimintaperiaatteen. Myös avaimenreikähitsauksen periaate on esitetty. Ruostumattomien terästen yleisimmät seosaineet ovat esitelty, kuten myös syy niiden seostamiseen. Ruostumattomat duplex-teräkset on esitelty samoin kuin lean duplex teräkset. Kokeellisen osion koehitsit hitsattiin osin samalla tuotantolinjalla lopputuotteen kanssa ja osin laboratoriossa. Koemateriaaleina olivat lean duplex teräkset 1.4162 ja 1.4362 joiden materiaalipaksuudet olivat 1.2 mm ja 1.5 mm. Hitsatuille lamelleille tehtiin painetestaus. Makroskopiaa ja valomikroskopiaa käytettiin koehitsien arvioinnissa kuten myös ristivetokoetta. Kiinnostavimmista hitseistä määritettiin myös faasisuhde. Lean duplex teräs 1.4362 havaittiin sopivammaksi laaduksi tämän kaltaisessa sovelluksessa, mutta myös laatu 1.4162 täyttää sovelluksen hitsille asetetut vaatimukset, tosin huomattavasti pienemmässä parametri ikkunassa. Valittu menetelmä faasisuhteen määrittämiseen osoittautui epätarkaksi, joten faasisuhteen osalta tämän tutkimuksen tulokset ovat vain suuntaa-antavia.
Resumo:
The desire to create a statistical or mathematical model, which would allow predicting the future changes in stock prices, was born many years ago. Economists and mathematicians are trying to solve this task by applying statistical analysis and physical laws, but there are still no satisfactory results. The main reason for this is that a stock exchange is a non-stationary, unstable and complex system, which is influenced by many factors. In this thesis the New York Stock Exchange was considered as the system to be explored. A topological analysis, basic statistical tools and singular value decomposition were conducted for understanding the behavior of the market. Two methods for normalization of initial daily closure prices by Dow Jones and S&P500 were introduced and applied for further analysis. As a result, some unexpected features were identified, such as a shape of distribution of correlation matrix, a bulk of which is shifted to the right hand side with respect to zero. Also non-ergodicity of NYSE was confirmed graphically. It was shown, that singular vectors differ from each other by a constant factor. There are for certain results no clear conclusions from this work, but it creates a good basis for the further analysis of market topology.