1,177 research outputs found

    Sleep detection with photoplethysmography for wearable-based health monitoring

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    Remote health monitoring has gained increasing attention in the recent years. Detecting sleep patterns provides users with insights on their personal health issues, and can help in the diagnosis of various sleep disorders. Conventional methods are focused on the acceleration data, or are not suitable for continuous monitoring, like the polysomnography. Wearable devices enable a way to continuously measure photoplethysmography signal. Photoplethysmography signal contains information on multiple physiological systems, and can be used to detect sleep patterns. Sleep detection using wearable-based photoplethysmography signal offers a convenient and easy way to monitor health. In this thesis, a photoplethysmography-based sleep detection method for wearable-based health monitoring is described. This technique aims to separate wakefulness and asleep states with adequate accuracy. To examine the importance of good quality data in sleep detection, the quality of the signal is assessed. The proposed method uses statistical and heart rate based features extracted from the photoplethysmography signal. Using the most relevant features, various supervised learning algorithms are trained, compared and evaluated. These algorithms are logistic regression, decision tree, random forest, support vector machine, k-nearest neighbors, and Naive Bayes. The best performance is obtained by the random forest classifier. The method received an overall accuracy of 81 percent. It was able to detect the sleep periods with 86 percent accuracy and the awake periods with 74 percent accuracy. Motion artifacts occurring during the awake time caused distortion to the signal. Features related to the shape of the signal improved the accuracy of sleep detection, since signal distortion was associated with the awake time. It is concluded that photoplethysmography signal provides a good alternative for wearable-based sleep detection. Future studies with more comprehensive sleep level analysis could be conducted to provide valuable information on the quality of sleep.Viime vuosina etÀnÀ tapahtuva terveyden seuranta on saanut yhÀ enemmÀn huomiota. Unen tunnistaminen antaa kÀyttÀjille tietoa heidÀn henkilökohtaisista terveysongelmistaan ja voi auttaa erilaisten unihÀiriöiden diagnosoinnissa. Tavanomaiset menetelmÀt kÀyttÀvÀt kiihtyvyyteen perustuvaa dataa, tai eivÀt ole soveltuvia jatkuvaan seurantaan, kuten polysomnografia. Puettavan teknologian avulla fotopletysmografiasignaalin jatkuva mittaus on mahdollista. Fotopletysmografiasignaali sisÀltÀÀ tietoa useista fysiologisista jÀrjestelmistÀ ja sitÀ voidaan kÀyttÀÀ unen tunnistamiseen. Puettavan teknologian avulla mitatun fotopletysmografiasignaalin kÀyttö unen tunnistuksessa tarjoaa kÀtevÀn ja helpon tavan seurata terveyttÀ. TÀssÀ diplomityössÀ kuvataan fotopletysmografiaan perustuva unenhavaitsemismenetelmÀ, joka soveltuu puettavaa teknologiaa hyödyntÀvÀÀn terveyden seurantaan. Tekniikalla pyritÀÀn erottamaan hereillÀ olo ja uni riittÀvÀn tarkasti. Signaalin laatu arvioidaan, jotta voidaan tutkia datan laadun tÀrkeys unen tunnistuksessa. Kehitetty menetelmÀ kÀyttÀÀ tilastollisia ja sykkeeseen perustuvia ominaisuuksia, jotka on erotettu fotopletysmografiasignaalista. TÀrkeimpiÀ ominaisuuksia kÀyttÀmÀllÀ erilaisia valvottuja oppimisalgoritmeja koulutetaan, vertaillaan ja arvioidaan. KÀytetyt algoritmit ovat logistinen regressio, pÀÀtöspuu, satunnainen metsÀ, tukivektorikone, k-lÀhimmÀt naapurit ja Naive Bayes. Paras tulos saadaan kÀyttÀmÀllÀ satunnainen metsÀ -algoritmia. MenetelmÀllÀ saavutetaan 81 prosentin kokonaistarkkuus. Uni pystytÀÀn tunnistamaan 86 prosentin tarkkuudella ja hereillÀ olo 74 prosentin tarkkuudella. HereillÀ ollessa liikkeestÀ johtuvat hÀiriöt aiheuttavat vÀÀristymÀÀ signaaliin. Signaalin muotoon liittyvÀt ominaisuudet paransivat unentunnistuksen tarkkuutta, koska signaalin vÀÀristyminen yhdistettiin hereillÀoloaikaan. Tutkimuksen tuloksista voidaan tehdÀ johtopÀÀtös, ettÀ fotopletysmografiasignaali tarjoaa hyvÀn vaihtoehdon puettavaa teknologiaa hyödyntÀvÀÀn unen tunnistamiseen. Tulevaisuudessa unen eri vaiheita voitaisiin tutkia kattavammin, jolloin saataisiin arvokasta tietoa unen laadusta

    The Roots of Entrepreneurial Research

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    Research in entrepreneurship has a long radition and there is considerable knowledge within the field. However, in many instances, researches today do not do their ground work sufficiently well

    Why Do Politicians Implement Central Bank Independence Reforms?

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    It is something of a puzzle that politicians around the world have chosen to give up power to independent central banks, thereby reducing their possibilities to fine-tune the economy. In this paper the determinants of central bank independence (CBI) reforms are studied using a new data set on the possible event of such reforms in 119 countries. According to the data, as much as 81 countries had implemented CBI-reforms during the study period. The results indicate, moreover, that policymakers are more likely to delegate power to independent central banks when the foreign debt is relatively high. In non-OECD countries, the likelihood of a CBI-reform also seems to increase when policymakers face a high probability of getting replaced.Institutional reforms; inflation; time-inconsistency; political stability; probit

    Pioneers in Entrepreneurship Research, New Frontiers of Entrepreneurship

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    Growth Effects from Trade Diversification in The East African Community

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    The purpose of this thesis is to investigate the relationship between trade diversity and growth in the East African Community. This was done by measuring different levels of diversification in exports and further test if they could contribute to explaining the different growth levels between member countries. Using data collected for the five member countries; Burundi, Kenya, Rwanda, Tanzania and Uganda over a thirteen year period, the tests investigated whether the traditional growth models, with the assumption of unconditional convergence, could explain the different growth rates or if there seemed to be other underlying structures that can’t be explained through these models. A sign of divergence in growth was found indicating other explanatory variables than used in traditional models. Further adding measures of export diversity, a correlation between export diversity and GDP per capita growth was found

    Why won't water managers use new scientific computer models? The co-production of a perceived science-practice gap

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    The uptake of scientific computer models in water management is challenging. Scientists often face calls to improve stakeholder engagement procedures. However, the involvement of representatives of water management agencies has been common practice in scientific projects for at least a decade. It is therefore questionable whether more stakeholder involvement would lead to greater use of scientific models in water management. This study suggests that computer modeling has historically developed differently in water science and water management. Scientific research has focused on continuous improvement of model process representation, while water management has emphasised usability. Today, the reliance on modeling software packages in water management, exacerbated by the dynamics in the field, mitigates against the adoption of new scientific modeling tools.Die EinfĂŒhrung wissenschaftlicher Computermodelle in der Wasserwirtschaft ist eine Herausforderung. Wissenschaftler sehen sich dabei oft mit der Forderung konfrontiert, die Verfahren zur Einbindung von Interessengruppen zu verbessern. Die Einbeziehung von Vertretern der Wasserwirtschaftsbehörden ist jedoch seit mindestens einem Jahrzehnt bei wissenschaftlichen Projekten gĂ€ngige Praxis. Es ist daher fraglich, ob eine stĂ€rkere Beteiligung von Akteuren zu einer breiteren Nutzung wissenschaftlicher Modelle in der Wasserwirtschaft fĂŒhren wĂŒrde. Diese Studie legt nahe, dass sich die Computermodellierung in der Wasserwissenschaft und der Wasserwirtschaft historisch unterschiedlich entwickelt hat. In der wissenschaftlichen Forschung wurde der Schwerpunkt auf eine kontinuierliche Verbesserung der Modelle zur Prozessdarstellung gelegt, wĂ€hrend in der Wasserwirtschaft die Benutzerfreundlichkeit im Vordergrund stand. Heute steht die AbhĂ€ngigkeit von Modellierungssoftware in der Wasserwirtschaft, verstĂ€rkt durch die Dynamik in diesem Bereich, der EinfĂŒhrung neuer wissenschaftlicher Modellierungswerkzeuge entgegen

    Density of Tengmalm’s Owl in relation to food supply through a climate- and landscape gradient

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    SmĂ„dĂ€ggdjur har inventerats i VĂ€sterbottens lĂ€n sedan 1971. Inventeringen genererar bakgrundsdata över populationsdynamik hos smĂ„dĂ€ggdjur, vilket anvĂ€nds för tolkning av populationsförĂ€ndringar i kringliggande trofiska nivĂ„er. FrĂ„n och med 1980 finns Ă€ven inventeringsdata över pĂ€rlugglans, Aegolius funereus, hĂ€ckningsdensitet över samma omrĂ„den. Detta möjliggör en inblick i hur belĂ€ggning av pĂ€rluggla pĂ„verkas av en varierande sorktillgĂ„ng. PĂ€rlugglans basföda utgörs av skogssork, Myodes glaerolus, grĂ„siding, Myodes rufocanus, och Ă„kersork, Microtus agrestis, vilka Ă€ven Ă€r fokusarter för den hĂ€r studien. Tack vare den kontinuerliga inventeringen har det setts en minskning av grĂ„siding i Vindeln sedan 1971. Att undersöka huruvida pĂ€rlugglebelĂ€ggningen pĂ„verkats av grĂ„sidingens minskning Ă€r ett av mĂ„len med den hĂ€r studien. Det andra mĂ„let med studien Ă€r att undersöka om belĂ€ggningen av pĂ€rluggla följer sorktillgĂ„ngen mellan tre omrĂ„den med skillnader i klimat och landskapsstruktur. FokusomrĂ„dena Ă€r AmmarnĂ€s, Vindeln och kustlandet. Data frĂ„n pĂ€rluggleinventering jĂ€mförs med data frĂ„n sorkinventering över samma omrĂ„de. Resultaten tyder pĂ„ att belĂ€ggningen av pĂ€rluggla följer sorktillgĂ„ngen i respektive omrĂ„de och att bĂ„de sorktillgĂ„ng och pĂ€rlugglebelĂ€ggning Ă€r högst i anslutning till omrĂ„den med större andel Ă€ldre barrskog. Andelen hĂ€ckande pĂ€rlugglor i Vindeln har haft en minskande trend sedan grĂ„sidingen minskat i Vindeln, det Ă€r dock svĂ„rt att avgöra om orsaken Ă€r just grĂ„sidingens minskning eller om det beror pĂ„ att den totala sorktillgĂ„ngen minskade under en tioĂ„rsperiod eller andra faktorer.Since 1971 there has been an inventory of small mammals in the north of Sweden. The inventory generates background data of the dynamics in populations of small mammals which is used to understand changes in surrounding trophic levels. Since 1980 there is also inventory data of the breeding density of Tengmalm’s owl, Aegolius funereus, from the same areas. These two inventories enable analyses of how Tengmalm’s owl is affected by a varying vole supply. The staple food for Tengmalm’s owl consists of the bank vole, Myodes glaerolus, the grey-sided vole, Myodes rufocanus, and the field vole, Microtus agrestis. These three voles are also the focus species for this study. The long-term data from Vindeln has shown a considerable decrease of the grey-sided vole since 1971. The first aim with this study is to analyse if the breeding density of Tengmalm’s owl follows the vole supply through a climate- and landscape gradient. The focus areas are AmmarnĂ€s, Vindeln and the coast land. The second aim is to analyse whether the decrease of grey-sided vole influenced the breeding density of Tengmalm’s owl in Vindeln. The owl inventory data is compared with the vole inventory data from the same area. The results indicate that the breeding density of Tengmalm’s owl is correlated with the vole supply in each area. The vole supply and subsequently the breeding density of Tengmalm’s owl was higher in areas with larger proportion of older boreal forest. The breeding density of Tengmalm’s owl in Vindeln had a decreasing trend along with the grey-sided vole. Whether it is the lack of grey-sided vole which is the cause or not remains unclear. The low breeding density may as well be caused by a reduced total vole supply or other factors

    Future management of Laisriver Brown trout

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    The life history and coexistence of subpopulations of brown trout in the same drainage area are relatively well known. The three forms of trout; sea-run, lake-run and resident, can all be present in the same location at some period of their life cycle, e.g. during the parr stage or at spawning. Despite the presence of all three forms, mostly the sea-run strategy is targeted in management actions from fishery organizations. Commonly this is done by compensatory stocking, even though the survival and fate of stocked individuals are not fully understood. This study investigates the fate of two groups of brown trout in the Laisriver in northern Sweden; stocked sea-run hatchery-reared juveniles and wild adult trout. This was done by tagging and tracking using acoustic telemetry during 2019 and 2020 to 2021. In addition, a genetic comparison of the adult trout with a genetic baseline for the whole Vindelriver system. My results indicate that survival of stocked hatchery-reared juvenile trout is low and that wild adult trout in Laisriver is from a common origin with a genetic profile partly unique to Laisriver and that they can adopt both resident and anadromous life histories. The home range size for the adult trout that has adopted a resident life history reached over 80 km including both stream sections and lakes but was limited to the Laisriver only. My conclusion is that future management actions should aim on enhancing the resident trout stock rather than stocks assumed to be purely sea-run. I suggest that this should be done by habitat restoration measures and improved fishing regulations to protect the important large trout individuals. Finally, I highlight the need for future monitoring of movement patterns of adult trout to increase the knowledge which will lead to further improved management actions in the future

    Kyvykkyydet, rakennemuutos ja ilmastopolitiikka

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    In order to hold the global warming below 2 degrees Celsius, also developing countries are required to urgently limit their greenhouse gas emissions. However, developing countries tend to fear that climate policy measures could harm their development. Assessing whether or not such worries are justified requires deep understanding of the drivers of economic development. On the one hand, it is currently widely accepted that societal capabilities, including aspects like institutions, various infrastructure, human capital and social capital, are the determinants of long-term economic performance. On the other hand, development is known to be accompanied by structural change. Recent empirical evidence provides support to the hypothesis that capabilities and structural change are fundamentally linked. It seems that the expansion and the diversification of production contribute to capabilities which then enable further diversification into productive activities that require these capabilities. This thesis seeks to explain how societal capabilities, structural change and development interact, and what this interaction implies for climate policy. A multi-sector endogenous growth model driven by the interplay of capabilities and structural change is proposed. The model implies that if climate policy interferes with structural change by harming the operation of some sectors, economic growth may temporarily slow down or even permanently stagnate. Hence, climate policy can threat development, whereby poorer countries are more severely affected. To avoid adverse effects, this theory suggests a focus on capabilities in policy design.Jotta ilmaston lÀmpeneminen voitaisiin rajoittaa kahteen asteeseen, myös kehittyvien maiden on pikaisesti rajoitettava kasvihuonekaasupÀÀstöjÀÀn. Useat kehittyvÀt maat kuitenkin pelkÀÀvÀt, ettÀ ilmastopolitiikka voi vahingoittaa niiden taloudellista kehitystÀ. Jotta voitaisiin arvioida, onko huoli perusteltu, on ymmÀrrettÀvÀ taloudellisen kehityksen ajureita. On yleisesti tunnustettua, ettÀ yhteiskunnalliset kyvykkyydet, sisÀltÀen muun muassa instituutiot, erilaisen infrastruktuurin sekÀ inhimillisen ja sosiaalisen pÀÀoman, mÀÀrittÀvÀt talouden kehityksen pitkÀllÀ aikavÀlillÀ. Toisaalta talouden rakennemuutoksen tiedetÀÀn lÀhes poikkeuksetta esiintyvÀn talouden kehityksen yhteydessÀ. ViimeisimmÀt empiiriset tutkimustulokset tukevat hypoteesia, jonka mukaan kyvykkyydet ja rakennemuutos liittyvÀt perustavanlaatuisesti toisiinsa. Vaikuttaa siltÀ, ettÀ tuotannon laajentaminen ja monipuolistaminen kehittÀvÀt kyvykkyyksiÀ. Uudet kyvykkyydet taas mahdollistavat uudenlaiset tuotantoaktiviteetit, joille juuri nÀmÀ kyvykkyydet ovat toimintaedellytys. TÀmÀ diplomityö pyrkii selittÀmÀÀn yhteiskunnallisten kyvykkyyksien, rakennemuutoksen ja taloudellisen kehityksen vuorovaikutusta ja sen seurauksia ilmastopolitiikan kannalta. TyössÀ esitetÀÀn monisektorinen endogeeninen talouskasvumalli, jossa kyvykkyyksien ja rakennemuutoksen vuorovaikutus on kasvun ajuri. Mallin valossa talouskasvu saattaa vÀliaikaisesti hidastua tai jopa pysyvÀsti lamaantua, jos ilmastopolitiikka puuttuu rakennemuutokseen hÀiritsemÀllÀ joidenkin sektorien toimintaa. TÀten ilmastopolitiikka voi uhata kehitystÀ. Vaikutukset vÀhemmÀn kehittyneisiin maihin ovat suurempia. Jotta vahingolliset seuraukset voidaan vÀlttÀÀ, tÀmÀ teoria kehottaa huomioimaan kyvykkyydet politiikan suunnittelussa

    Matkailu ja ympÀristöystÀvÀllisyys : Suomeen saapuvien matkailijoiden kokemuksia matkailupalveluista

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    TÀmÀn opinnÀytetyön tarkoituksena on luoda parempi ymmÀrrys siitÀ, tuoko vastuullisuus arvoa asiakkaille sekÀ kuinka paljon matkailijat arvostavat vastuullisuutta matkoillaan. Tavoitteena oli selvittÀÀ, millaista arvoa palvelujen ympÀristöystÀvÀllisyys muodostaa Suomeen saapuville matkailijoille. OpinnÀytetyö suoritettiin toimeksiantona Suomen Reilun Matkailun yhdistys Ry:lle. Teoreettinen viitekehys kÀsittelee matkailua sekÀ sen eri muotoja, kestÀvÀÀ matkailua sekÀ erilaisia matkailutyyppejÀ. LÀhdeaineistona kÀytettiin matkailutilastoja etenkin Suomesta. Suomen matkailutilastoja apuna kÀyttÀen oli mahdollista saada tietoa matkailun kehityksestÀ ja nykytilasta. LisÀksi teoriaosuudessa kÀsitellÀÀn palvelun arvoa, sen muodostumista, sekÀ ympÀristöystÀvÀllisyyttÀ matkailupalveluissa. Tutkimus toteutettiin laadullisella eli kvalitatiivisella menetelmÀllÀ, ja aineistoa kerÀttiin teemahaastattelujen avulla, joita kertyi yhteensÀ 9 kappaletta. Haastateltavat olivat 20 - 30 vuotiaita Suomeen saapuneita itsenÀisiÀ matkailijoita. Tutkimukseen ei rajattu kansallisuutta, ja haastateltavat saapuivat useista eri maista. Haastattelut toteutettiin maaliskuun aikana pÀÀkaupunkiseudulla. Haastateltavista enemmistö majoittui HelsingissÀ sijaitsevissa hostelleissa, ja osa ystÀviensÀ luona. Tutkimuksen tuloksista selvisi, ettÀ haastateltavat olivat tietoisia heidÀn matkojensa vaikutuksista ympÀristöön. Erityisesti negatiiviset vaikutukset ympÀristöön olivat haastateltavilla tiedossa ja niitÀ pyrittiinkin omilla valinnoillaan minimoimaan. He eivÀt palveluita valittaessaan halunneet tuottaa valinnoillaan lisÀhaittaa ympÀristölle, vaikka he eivÀt aktiivisesti etsineetkÀÀn kaikista ympÀristöystÀvÀllistÀ vaihtoehtoa. Tulevaisuudessa tÀrkeÀÀ olisi tutkia lisÀÀ sekÀ asiakaskokemusta, ettÀ palvelun tuottamaa arvoa asiakkaille, etenkin matkailun osalta Suomessa
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