On Transmission System Design for Wireless Broadcasting

This thesis considers aspects related to the design and standardisation of transmission systems for wireless broadcasting, comprising terrestrial and mobile reception. The purpose is to identify which factors influence the technical decisions and what issues could be better considered in the design process in order to assess different use cases, service scenarios and end-user quality. Further, the necessity of cross-layer optimisation for efficient data transmission is emphasised and means to take this into consideration are suggested. The work is mainly related terrestrial and mobile digital video broadcasting systems but many of the findings can be generalised also to other transmission systems and design processes. The work has led to three main conclusions. First, it is discovered that there are no sufficiently accurate error criteria for measuring the subjective perceived audiovisual quality that could be utilised in transmission system design. Means for designing new error criteria for mobile TV (television) services are suggested and similar work related to other services is recommended. Second, it is suggested that in addition to commercial requirements there should be technical requirements setting the frame work for the design process of a new transmission system. The technical requirements should include the assessed reception conditions, technical quality of service and service functionalities. Reception conditions comprise radio channel models, receiver types and antenna types. Technical quality of service consists of bandwidth, timeliness and reliability. Of these, the thesis focuses on radio channel models and errorcriteria (reliability) as two of the most important design challenges and provides means to optimise transmission parameters based on these. Third, the thesis argues that the most favourable development for wireless broadcasting would be a single system suitable for all scenarios of wireless broadcasting. It is claimed that there are no major technical obstacles to achieve this and that the recently published second generation digital terrestrial television broadcasting system provides a good basis. The challenges and opportunities of a universal wireless broadcasting system are discussed mainly from technical but briefly also from commercial and regulatory aspect

Expertise and decision making among clinicians in investigations of alleged child sexual abuse

The purpose of the present thesis was to explore different aspects of decision making and expertise in investigations of child sexual abuse (CSA) and subsequently shed some light on the reasons for shortcomings in the investigation processes. Clinicians’ subjective attitudes as well as scientifically based knowledge concerning CSA, CSA investigation and interviewing were explored. Furthermore the clinicians’ own view on their expertise and what enhances this expertise was investigated. Also, the effects of scientific knowledge, experience and attitudes on the decision making in a case of CSA were explored. Finally, the effects of different kinds of feedback as well as experience on the ability to evaluate CSA in the light of children’s behavior and base rates were investigated. Both explorative and experimental methods were used. The purpose of Study I was to investigate whether clinicians investigating child sexual abuse (CSA) rely more on scientific knowledge or on clinical experience when evaluating their own expertise. Another goal was to check what kind of beliefs the clinicians held. The connections between these different factors were investigated. A questionnaire covering items concerning demographic data, experience, knowledge about CSA, selfevaluated expertise and beliefs about CSA was given to social workers, child psychiatrists and psychologists working with children. The results showed that the clinicians relied more on their clinical experience than on scientific knowledge when evaluating their expertise as investigators of CSA. Furthermore, social workers possessed stronger attitudes in favor of children than the other groups, while child psychiatrists had more negative attitudes towards the criminal justice system. Male participants held less strong beliefs than female participants. The findings indicate that the education of CSA investigators should focus more on theoretical knowledge and decision making processes as well as the role of beliefs In Study II school and family counseling psychologists completed a Child Sexual Abuse Attitude and Belief Scale. Four CSA related attitude and belief subscales were identified: 1. The Disclosure subscale reflecting favoring a disclosure at any cost, 2. The Pro-Child subscale reflecting unconditional belief in children's reports, 3. The Intuition subscale reflecting favoring an intuitive approach to CSA investigations, and 4. The Anti Criminal Justice System subscale reflecting negative attitudes towards the legal system. Beliefs that were erroneous according to empirical research were analyzed separately. The results suggest that some psychologists hold extreme attitudes and many erroneous beliefs related to CSA. Some misconceptions are common. Female participants tended to hold stronger attitudes than male participants. The more training in interviewing children the participants have, the more erroneous beliefs and stronger attitudes they hold. Experience did not affect attitudes and beliefs. In Study III mental health professionals’ sensitivity to suggestive interviewing in CSA cases was explored. Furthermore, the effects of attitudes and beliefs related to CSA and experience with CSA investigations on the sensitivity to suggestive influences in the interview were investigated. Also, the effect of base rate estimates of CSA on decisions was examined. A questionnaire covering items concerning demographic data, different aspects of clinical experience, self-evaluated expertise, beliefs and knowledge about CSA and a set of ambiguous material based on real trial documents concerning an alleged CSA case was given to child mental health professionals. The experiment was based on a 2 x 2 x 2 x 2 (leading questions: yes vs no) x (stereotype induction: yes vs no) x (emotional tone: pressure to respond vs no pressure to respond) x (threats and rewards: yes vs no) between-subjects factorial design, in which the suggestiveness of the methods with which the responses of the child were obtained were varied. There was an additional condition in which the material did not contain any interview transcripts. The results showed that clinicians are sensitive only to the presence of leading questions but not to the presence of other suggestive techniques. Furthermore, the clinicians were not sensitive to the possibility that suggestive techniques could have been used when no interview transcripts had been included in the trial material. Experience had an effect on the sensitivity of the clinicians only regarding leading questions. Strong beliefs related to CSA lessened the sensitivity to leading questions. Those showing strong beliefs on the belief scales used in this study were even more prone to prosecute than other participants when other suggestive influences than leading questions were present. Controversy exists regarding effects of experience and feedback on clinical decision making. In Study IV the impact of the number of handled cases and of feedback on the decisions in cases of alleged CSA was investigated. One-hundred vignettes describing cases of suspected CSA were given to students with no experience with investigating CSA. The vignettes were based on statistical data about symptoms and prevalence of CSA. According to the theoretical likelihood of CSA the children described were categorized as abused or not abused. The participants were asked to decide whether abuse had occurred. They were divided into 4 groups: one received feedback on whether their decision was right or wrong, one received information about cognitive processes involved in decision making, one received both, and one did not receive feedback at all. The results showed that participants who received feedback on their performance made more correct positive decisions and participants who got information about decision making processes made more correct negative decisions. Feedback and information combined decreased the number of correct positive decisions but increased the number of correct negative decisions. The number of read cases had in itself a positive effect on correct positive decision.

Neurophysiologic diagnosis, clinical symptoms and neuropathologic findings in polyneuropathies

Tausta: Polyneuropatia (PNP) on ääreishermoston sairaus, joka aiheuttaa laaja-alaisia, yleensä symmetrisiä vaurioita ääreishermostossa. PNP:aan johtavia syitä on satoja. Tavoitteet: Löytää parhaat neurofysiologiset menetelmät uremian, myelooman hoidossa käytettävän talidomidin sekä Fabryn taudin aiheuttaman PNP:n diagnosoimiseksi. Fabryn taudissa tutkin lisäksi ohutsäieneuropatian aiheuttamia neuropatologisia löydöksiä iholta otetusta koepalasta. Tutkimuksissa kartoitettiin lisäksi PNP:n aiheuttamien subjektiivisten oireiden korrelaatio neurofysiologisten ja neuropatologisten löydösten kanssa. Munuaisten vajaatoimintaa sairastavilla potilailla tavoitteena oli tutkia dialyysihoidon tehon vaikutusta autonomisen hermoston toimintaan sekä yhden dialyysikerran vaikutusta neurofysiologisiin löydöksiin. Aineisto ja menetelmät: I: Tutkittiin 21 uremiapotilaan sensoristen ja motoristen hermojen vasteet, värinä- sekä lämpötuntokynnykset ennen ja jälkeen hemodialyysin. Subjektiiviset PNP oireet kartoitettiin PNP oireita kysyvillä kaavakkeella. II:12 talidomidi hoitoa saavaa myeloomapotilasta, tutkimuksen menetelmät olivat samat kuin tutkimuksessa I. III: 12 Fabryn tautia sairastavaa potilasta, edellä mainittujen neurofysiologisten tutkimusten lisäksi potilailta otettiin ihobiopsia säären alueelta. Ihobiopsiasta laskettiin ohuiden hermosyiden määrä koepalan värjäyksen jälkeen. Subjektiiviset PNP oireet kartoitettiin kyselykaavakkeella. Sydämen sykevaihtelu tutkittiin levossa taajuustason analyysillä. IV: 32 uremiapotilaan autonomisen hermoston toimintaa tutkittiin sydämen sykevaihtelun aikatason analysillä, paksujen myelinoituneiden säikeiden toimintaa tutkittiin perifeeristen sensoristen hermojen mittauksilla toistetusti noin 2.9 vuoden aikana. Tulokset: Ureemisen PNP:n diagnostiikassa herkimmät tutkimukset ovat F-aaltojen parametrit alaraajojen motorisista hermoista, värinätuntokynnys alaraajoista sekä suralishermon amplitudi. Positiiviset PNP oireet uremiassa korreloivat värinätunto-kynnyksen sekä sensoristen hermojen neurografialöydösten kanssa. Neurofysiologisten tutkimusten ajankohdalla dialyysiajankohtaan nähden ei ole merkitystä. Talidomidi-PNP on pääasiassa sensorinen, mutta motoriset syyt ovat lievästi vaurioituneet. Talidomidi PNP:ssa subjektiiviset oireet korreloivat huonosti neurofysiologisten löydösten kanssa. Fabryn taudissa naisilla on oletettua enemmän ohutsäieneuropatian aiheuttamia oireita ja löydöksiä. Paksujen säikeiden löydöksiä ei tullut esiin. Ohutsäieneuropatian diagnostiikassa ihobiopsia ja kvantitatiiviset tuntokynnysmittaustestit täydentävät toisiaan. Tehokas dialyysi parantaa autonomisen hermoston toimintaa uremiapotilailla. Päätelmät: Erityyppisten polyneuropatioiden diagnostiikassa pitää etukäteen valita PNP tyypille oikeat tutkimusmenetelmät raskaiden tutkimuspatterien vähentämiseksi sekä diagnostiikan parantamiseksi. PNP:n aiheuttamat oireet ja kliiniset löydökset pitää aina tutkia, mutta yksin ne eivät ole herkkiä PNP:n diagnostiikassa.

Determining risk potential through accidents and near-accidents: an empirical study in a steel factory

Fatal and permanently disabling accidents form only one per I cent of all occupational accidents but in many branches of industry they account for more than half the accident costs. Furthermore the human suffering of the victim and his family is greater in severe accidents than in slight ones. For both human and economic reasons the severe accident risks should be identified befor injuries occur. It is for this purpose that different safety analysis methods have been developed . This study shows two new possible approaches to the problem.. The first is the hypothesis that it is possible to estimate the potential severity of accidents independent of the actual severity. The second is the hypothesis that when workers are also asked to report near accidents, they are particularly prone to report potentially severe near accidents on the basis of their own subjective risk assessment. A field study was carried out in a steel factory. The results supported both the hypotheses. The reliability and the validity of post incident estimates of an accident's potential severity were reasonable. About 10 % of accidents were estimated to be potentially critical; they could have led to death or very severe permanent disability. Reported near accidents were significantly more severe, about 60 $ of them were estimated to be critical. Furthermore the validity of workers subjective risk assessment, manifested in the near accident reports, proved to be reasonable. The studied new methods require further development and testing. They could be used both in routine usage in work places and in research for identifying and setting the priorities of accident risks.

The Role of Network Competence in Internationalization of SMEs

Network competence is the ability of firms to manage their network of business relationships and to deal effectively with interactions in these relationships. The relationship between level of business relationship abilities of firms and their internationalization has been researched before, and found to be positive. However, what network competence specifically offers is an established scale with which to perform this examination quantitatively. This master’s thesis examined the role which this network competence plays in the internationalization of firms, more specifically in Finnish small and medium sized enterprises (SMEs). The theoretical part of the thesis consisted of examination into the nature of internationalization of SMEs, their business relationships, network competence and related concepts. The empirical part was conducted statistically with quantitative methods on data gathered from Finnish SMEs through a web-survey during 2008. Network competence was found to result in better internationalization among the examined Finnish SMEs with both subjective and objective performance measures, and firms with higher levels of network competence were found to be more likely to become international. On the other hand, speed of internationalization could not be linked to better network competence, and no clear industry-specific differences were found. The results show that by developing their network competence, Finnish SMEs can increase their chances of success and performance in their internationalization process

MCMC Analysis Of Classical Time Series Algorithms

Identification of order of an Autoregressive Moving Average Model (ARMA) by the usual graphical method is subjective. Hence, there is a need of developing a technique to identify the order without employing the graphical investigation of series autocorrelations. To avoid subjectivity, this thesis focuses on determining the order of the Autoregressive Moving Average Model using Reversible Jump Markov Chain Monte Carlo (RJMCMC). The RJMCMC selects the model from a set of the models suggested by better fitting, standard deviation errors and the frequency of accepted data. Together with deep analysis of the classical Box-Jenkins modeling methodology the integration with MCMC algorithms has been focused through parameter estimation and model fitting of ARMA models. This helps to verify how well the MCMC algorithms can treat the ARMA models, by comparing the results with graphical method. It has been seen that the MCMC produced better results than the classical time series approach.

Demonstration Platform for Visual Quality Metrics

This thesis presents two graphical user interfaces for the project DigiQ - Fusion of Digital and Visual Print Quality, a project for computationally modeling the subjective human experience of print quality by measuring the image with certain metrics. After presenting the user interfaces, methods for reducing the computation time of several of the metrics and the image registration process required to compute the metrics, and details of their performance are given. The weighted sample method for the image registration process was able to signifigantly decrease the calculation times while resulting in some error. The random sampling method for the metrics greatly reduced calculation time while maintaining excellent accuracy, but worked with only two of the metrics.

Paperin aistinvarainen arviointi

Paperin tärkeiden teknisten ominaisuuksien lisäksi myös paperin aistinvaraiset ominaisuudet ovat nousseet merkittäviksi parametreiksi paperia luonnehdittaessa. Aistinvaraisilla ominaisuuksilla tarkoitetaan ominaisuuksia, jotka ihminen aistii käsitellessään tuotetta. Tällaisia ominaisuuksia ovat esimerkiksi paperin karheus, liukkaus, jäykkyys sekä ääni paperia selattaessa. Paperin aistinvaraiset ominaisuudet luovat lukijalle mielikuvan lukemastaan lehdestä lehden sisällön lisäksi. Tämän työn tavoitteena oli kehittää olemassa olevan aistinvaraisten ominaisuuksien arviointiraadin toimintaa. Arviointimenetelmän tilalle pyrittiin löytämään toinen menetelmä sekä kehittämään uusi tulosten raportointimalli. Työssä käytettiin kahta subjektiivista arviointimenetelmää, parivertailua ja ranking-menetelmää. Tuloksia verrattiin aiemmin käytössä olleen referenssimenetelmän tuloksiin. Näytteistä arvioitiin karheus, liukkaus, tahmeus, jäykkyys, selailtavuus, äänen voimakkuus ja äänen laatu. Näiden lisäksi näytteiden miellyttävyyttä arvioitiin parivertailua käyttäen. Arvioitsijoiden yksimielisyyttä selvitettiin parivertailun yhteydessä. Näytteet olivat painamattomia, mutta painokoneen läpi menneitä lehtiformaattiin taitettuja. Visuaalisissa arvioinneissa käytettiin painettuja näytteitä samasta paperivalikoimasta. Arviointimenetelmien tuloksia vertailtaessa, voidaan menetelmien välillä havaita muutamia eroja. Sekä parivertailussa että ranking-menetelmässä näytteet jakaantuivat lähes kokonaan annetulle arviointiskaalalle, kun referenssimenetelmällä ne kasautuivat hyvin pienelle alueelle. Ranking-menetelmässä näytteet jakautuivat vielä laajemmalle kuin parivertailussa. Parivertailu erotteli näytteet paremmin toisistaan kuin referenssimenetelmä. Ranking-menetelmän ja parivertailun välillä vastaavaa eroa erotuskyvyssä ei havaittu. Tulosten perusteella voidaan sanoa, että parivertailu

Computational visual quality of digitally printed images

The problem of understanding how humans perceive the quality of a reproduced image is of interest to researchers of many fields related to vision science and engineering: optics and material physics, image processing (compression and transfer), printing and media technology, and psychology. A measure for visual quality cannot be defined without ambiguity because it is ultimately the subjective opinion of an “end-user” observing the product. The purpose of this thesis is to devise computational methods to estimate the overall visual quality of prints, i.e. a numerical value that combines all the relevant attributes of the perceived image quality. The problem is limited to consider the perceived quality of printed photographs from the viewpoint of a consumer, and moreover, the study focuses only on digital printing methods, such as inkjet and electrophotography. The main contributions of this thesis are two novel methods to estimate the overall visual quality of prints. In the first method, the quality is computed as a visible difference between the reproduced image and the original digital (reference) image, which is assumed to have an ideal quality. The second method utilises instrumental print quality measures, such as colour densities, measured from printed technical test fields, and connects the instrumental measures to the overall quality via subjective attributes, i.e. attributes that directly contribute to the perceived quality, using a Bayesian network. Both approaches were evaluated and verified with real data, and shown to predict well the subjective evaluation results.

Eurooppalainen näkökulma suomalaiseen kulttuurijohtamiseen ja suomalaiseen yhteiskuntaan sopeutuminen

Tässä tutkielmassa korostuu Euroopan sisäinen kulttuurillinen erilaisuus ja sen vaatimukset Suomessa toimiville monikansallisille organisaatioille. Eurooppalaista johtamista on tutkittu jo vuosikymmenten ajan, mutta erityisesti suomalaisesta, Suomessa työskentelevien eurooppalaisten näkökulmasta ei vastaavaa tutkimusta tiettävästi ole aiemmin tehty. Tutkimuksen tavoitteena on selvittää suomalaisen kulttuurin ja johtajuuden arvoeroja muiden Euroopan Unionin maiden kansalaisten näkökulmasta. Pohjois-Euroopan maista tutkimuksessa on mukana edustajia Ruotsista, Tanskasta ja Hollannista. Keski-Euroopan maista edustusta löytyy Saksasta ja Itävallasta, kun Etelä-Eurooppaa edustavat ranskalaiset ja italialaiset henkilöt. Itäisestä Euroopasta mukana on latvialaisia henkilöitä ja anglo-Euroopasta britannialaisia. Tutkimus kartoittaa tutkimukseen mukaan otettujen maiden yhteisö- ja johtamiskulttuurillisia törmäyskohtia suomalaisen kulttuurin kanssa, jotta Suomessa toimivat monikansalliset työyhteisöt löytäisivät yhä parempia strategioita eurooppalaisen ihmispääoman, eurooppalaisten työntekijöiden ja näiden osaamisen, johtamiseksi ja monikansallisen yhteisön toimivuuden ymmärtämiseksi ja parantamiseksi. Näitä törmäyskohtia tarkastellaan empiirisesti Hofsteden (1984) kulttuuridimensioiden, Housen ym. (1999) GLOBE-tutkimuksen ja Koopmanin ym. (1999) johtajuusulottuvuuksien avulla. Tutkimusaineisto koostuu Internet-pohjaisesta kyselystä, joka suoritettiin keväällä 2010. Siihen osallistui 75 Suomessa työskentelevää Euroopan Unionin kansalaista. Analysointimenetelmänä tutkimuksessa käytetään klusterointia, keskiarvoistuksia, Kruskall Wallisin testiä ja sisällönanalyysiä tukemaan määrällisen analyysin tuloksia ja tuomaan esiin siitä poikkeavia havaintoja. Tutkimuksen ytimessä on johtamiskulttuurilliset erot, joista tehdään laajempaa analyysiä edellä mainituin keinoin. Yhteisökulttuurillisia eroja havainnoidaan tutkimuskyselyyn perustuvien väittämien perusteella tehtyjen histogrammien avulla. Tutkimuksen tulokset osoittavat, että maantieteellinen, uskonnollinen tai poliittinen läheisyys eivät määritä kulttuurillista läheisyyttä tai johda kulttuurilliseen sopeutumiseen. Poliittinen raja kahden naapurin välillä saattaa johtaa saman asian kokemiseen kahdella täysin eri tavalla. Lisäksi tuloksista käy ilmi, että yhteisökulttuurilliset ja johtamiskulttuurilliset arvot eivät välttämättä kulje käsikkäin Suomessa työskentelevien eurooppalaisten näkökulmasta. Yleisinä kulttuurillisina kipukohtina tutkimuksessa nousee esiin suomalaisen kulttuurin sosiaalisuuden ja kommunikaation puutteellisuus, toisaalta suomalaiseen kulttuuriin sopeutumista helpottaa suomalainen rehellisyys ja suoruus. Johtamiskulttuurillisina haasteina eurooppalaiset kokevat suomalaisen tyyppijohtajan kyvyttömyyden riskien ottamiseen ja kannustusmenetelmien puutteet. Tämän lisäksi tutkimuksessa tulee ilmi useita tiettyihin kansallisuuksiin liittyviä törmäyskohtia. Tutkimus on nähtävä tämän hetken kuvauksena. Kulttuuritutkimus sisältää monia tekijöitä, jotka ovat jatkuvassa muutoksessa ja lisäksi hyvin subjektiivisia. Kulttuurijohtajuus merkitsee kuitenkin nyt ja tulevaisuudessa kykyä olla innovatiivinen, joustava ja herkkä sosiaalisille merkityksille.

Improving Quality of Life of Patients With Schizophrenia In Acute Psychiatric Wards

The overall goal of this study was to identify means by which the quality of life (QoL) of patients with schizophrenia could be improved in acute psychiatric wards. First, subjective QoL of patients (n=35) was explored. Second, two different QoL instruments (EuroQoL-5D, EQ-5D; Quality of Life Enjoyment and Satisfaction Questionnaire Short Form, Q-LES-Q SF) were examined. Third, patients’ (n=35) and nurses’ (n=29) perceptions of nursing interventions to support patients’ QoL were examined. Fourth, the effect of three different patient education methods on patients’ QoL (n=311) was compared. The data were collected during the period 2005-2007. Patients named health, family, leisure activities, work or study, and social relationships most frequently as their important QoL areas. It emerged that patients’ QoL was impaired. Examination of two QoL instruments showed that the EQ-5D has moderate and the Q-LES-Q SF good internal consistency. Moreover, both instruments proved to be reasonably valid and feasible for use with patients with schizophrenia. Altogether six nursing interventions which nurses use to support patients’ QoL, and which should be further developed were identified from nurses’ descriptions: interventions related to care planning, empowering interventions, social interventions, activating interventions, security interventions, and interventions to support physical health. Evaluation of different patient education methods showed that patients’ QoL improved significantly during follow-up. No significant differences between groups were found. In light of the findings it is recommended to assess QoL of patients with schizophrenia as a basis for care planning and care evaluation in clinical settings. Valid and feasible instruments should be used in this assessment. Moreover, it is recommend that nursing interventions should be further developed to better improve patients’ QoL.