59 resultados para DISTANCES


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In nature, many animals use body coloration to communicate with each other. For example, colorations can be used as signals between individuals of the same species, but also to recognise individuals of other species, and if they may comprise a threat or not. Many animals use protective coloration to avoid predation. The two most common strategies of protective coloration are camouflage and aposematism. Camouflaged animals have coloration that minimises detection, usually by matching colours or structures in the background. Aposematic animals, on the other hand, signal to predators that they are defended. The defence can be physical structures, such as spikes and hairs, or chemical compounds that make the animal distasteful or even deadly toxic. In order for the warning signal to be effective, the predator has to recognise it as such. Studies have shown that birds for example, that are important visual predators on insects, learn to recognise and avoid unpalatable prey faster if they contrast the background or have large internal contrasts. Typical examples of aposematic species have conspicuous colours like yellow, orange or red, often in combination with black. My thesis focuses on the appearance and function of aposematic colour patterns. Even though researchers have studied aposematism for over a century, there is still a lot we do not know about the phenomenon. For example, as it is crucial that the predators recognise a warning signal, aposematic colorations should assumingly evolve homogeneously and be selected for maximal conspicuousness. Instead, there is an extensive variation of colours and patterns among warning colorations, and it is not uncommon to find typical cryptic colours, such as green and brown in aposematic colour patterns. One hypothesis to this variation is that an aposematic coloration does not have to be maximally signalling in order to be effective, instead it is sufficient to have distinct features that can be easily distinguished from edible prey. To be maximally conspicuous is one way to achieve this, but not the only way. Another hypothesis is that aposematic prey that do not exhibit maximal conspicuousness can exploit both camouflage and aposematism in a distance-dependent fashion, by being signalling when seen close up but camouflaged at a distance. Many prey animals also make use of both strategies by shifting colour at different ecological conditions such as seasonal variations, fluctuations in food resources or between life stages. Yet another explanation for the variation may be that prey animals are usually exposed to several predator species that vary in visual perception and tolerance towards various toxins. The aim with this thesis is, by studying their functions, to understand why aposematic warning signals vary in appearance, specifically in the level of conspicuousness, and if warning coloration can be combined with camouflage. In paper I, I investigated if the colour pattern of the aposematic larva of the Apollo butterfly (Parnassius apollo) can switch function with viewing distance, and be signalling at close range but camouflaged at a distance, by comparing detection time between different colour variants and distances. The results show that the natural coloration has a dual distance-dependent function. Moreover, the study shows that an aposematic coloration does not have to be selected for maximal conspicuousness. A prey animal can optimise its coloration primarily by avoiding detection, but also by investing in a secondary defence, which presence can be signalled if detected. In paper II, I studied how easily detected the coloration of the firebug (Pyrrhocoris apterus), a typical aposematic species, is at different distances against different natural backgrounds, by comparing detection time between different colour variants. Here, I found no distance-dependent switch in function. Instead, the results show that the coloration of the firebug is selected for maximal conspicuousness. One explanation for this is that the firebug is more mobile than the butterfly larva in study I, and movement is often incompatible with efficient camouflage. In paper III, I investigated if a seasonal related colour change in the chemically defended striated shieldbug (Graphosoma lineatum) is an adaptation to optimise a protective coloration by shifting from camouflage to aposematism between two seasons. The results confirm the hypothesis that the coloration expressed in the late summer has a camouflage function, blending in with the background. Further, I investigated if the internal pattern as such increased the effectiveness of the camouflage. Again, the results are in accordance with the hypothesis, as the patterned coloration was more difficult to detect than colorations lacking an internal pattern. This study shows how an aposematic species can optimise its defence by shifting from camouflage to aposematism, but in a different fashion than studied in paper I. The aim with study IV was to study the selection on aposematic signals by identifying characteristics that are common for colorations of aposematic species, and that distinguish them from colorations of other species. I compared contrast, pattern element size and colour proportion between a group of defended species and a group of undefended species. In contrast to my prediction, the results show no significant differences between the two groups in any of the analyses. One explanation for the non-significant results could be that there are no universal characteristics common for aposematic species. Instead, the selection pressures acting on defended species vary, and therefore affect their appearance differently. Another explanation is that all defended species may not have been selected for a conspicuous aposematic warning coloration. Taken together, my thesis shows that having a conspicuous warning coloration is not the only way to be aposematic. Also, aposematism and camouflage is not two mutually exclusive opposites, as there are prey species that exploit both strategies. It is also important to understand that prey animals are exposed to various selection pressures and trade-offs that affect their appearance, and determines what an optimal coloration is for each species or environment. In conclusion, I hold that the variation among warning colorations is larger and coloration properties that have been considered as archetypically aposematic may not be as widespread and representative as previously assumed.

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Tämän tutkimuksen päätavoitteena oli luoda yleisellä tasolla kustannusmalli maarakennuskonepalveluita tuottavien pk-yritysten käyttöön ja käytännön päätöstilanteiden avuksi osana päätöksenteko organisaation ja myyntityötä tekevän portaan kustannustarkkailuun. Mallin luomisen tarkoituksena oli että mallia voidaan helposti muokata erilaisten myyntitilanteiden kannattavuuksien tarkasteluun ja sitä kautta malli luo käyttäjilleen etulyöntiaseman luodessa pitkiä palvelusopimuksia ja erilaisten projektityömaiden myyntisopimuksia simuloimalla kaluston siirtokustannuksia olemassa olevien tiedettyjen kustannustekijöiden toimesta. Teollisuudessa ja palvelujentarjoajapuolella on vastaavia malleja esitetty, mutta erityisesti maarakennuspuolen ja konevuokrauksen kustannuslaskentamalleja ei julkisesta ole juurikaan saatavilla. Työn kustannusmallin muutoksia simuloitiin ja testattiin luomalla erilaisia kysyntäskenaarioita joista yksi esitellään tarkemmin työn testausosiossa. mallilla on helppo kasata kustannusdataa erilaisina yhtälöinä miten uudet työmaat ovat kannattavampia luomalla kokonaisvaltaisesti paljon lisää uusia työkohteita. Kustannusmallin rakentamiselle oli kysyntää ja tärkeänä tietona pidettiin kokonaisvaltaista muutosta ja tietoa millä tehollisilla tunneilla vastaavat hankinnat olisivat kannattavia. Työn teoriaosa pohjautuu pääasiassa hinnoittelun, kannattavuuden ja investointilaskelmien teoriaan, artikkeleihin ja tutkimuksiin sekä kirjoihin. Työn empiirinen osa perustuu arvioihin tämän hetken hintatasoista sekä arvioihin kustannusten kertymisestä maarakennuspalveluita tuottavissa pk-yrityksissä joissa organisaatiokaavio on matala ja toiminta tehokasta. Keskeisimmät tulokset liittyvät siihen miten kustannuksia tulee huomioida erilaisille asiakkaille ja millainen kustannusmalli on käyttökelpoinen eri tilanteissa.

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Hihnakuljettimia käytetään muun muassa voimalaitos- ja sellutehdasympäristöissä kuljettamaan kiinteää polttoainetta tai haketta pitkiä matkoja. Pitkät hihnakuljettimet asennetaan yleensä teräsristikoista rakennettujen kuljetinsiltojen sisään. Kuljetinsilta toimii siis hihnakuljettimen ja hoitokäytävän runkona sekä suojaa kuljetinta ja kuljetettavaa materiaalia säältä. Tässä diplomityössä on laadittu mitoitustyökalu, jolla voidaan nopeasti mitoittaa ristikkorakenteisen hihnakuljetinsillan sauvat sekä määrittää rakenteen massa. Laskentaohjelma on toteutettu Microsoft Excel -taulukkolaskentana. Sillan poikkileikkaus voi olla suljettu symmetrinen umpirakenne tai avorakenne, jossa on ulokkeellinen hoitotaso. Ristikon sauvat ovat RHS-putkia. Rakenteeseen voi vaikuttaa jatkuvia kuormia, pistekuormia sekä näistä johdetut, ekvivalenttiin staattiseen voimaan perustuvat maanjäristyskuormat. Diplomityössä on perehdytty mitoitustyökalussa sovellettuihin teorioihin. Voimasuureiden laskenta perustuu 2-tukisina palkkeina käsiteltävien siltalohkojen ratkaisuun ja palkkianalogiaan, jossa ristikon sauvavoimat ratkaistaan käsittelemällä ristikkoa palkkina. Sauvojen kestävyyden laskenta perustuu SFS-EN 1993-1-1 -normiin, joka on osa Eurocode -rakennesuunnittelunormistoa. Lisäksi työssä on käsitelty ristikkoliitosten mitoitusta SFS-EN 1993-1-8 mukaan. Mitoitusohjelman toimivuutta on testattu tarkastelemalla esimerkkisiltaa laaditulla mitoituspohjalla ja Autodesk Robot Professional 2013 -FE-analyysiohjelmisuolla. Tulosten perusteella mitoitustyökalua voidaan käyttää ainakin tarjousvaiheen nopeisiin tarkasteluihin ja omamassan määritykseen, mutta myös lopulliseen mitoitukseen, mikäli hyväksytään konservatiivinen mitoitus.

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This thesis investigates the influence of cultural distance on entrepreneurs’ negotiation behaviour. For this purpose, Turku was chosen as the unit of analysis due to the exponential demographic change experienced during the last two decades that has derived in a more diversified local environment. The research aim set for this study was to identify to what extent entrepreneurs face cultural distance, how cultural distance influences the entrepreneur’s negotiation behaviour and how can it be addressed in order to turn dissimilarities into opportunities. This study presented the relation and apparent dichotomy of cultural distance and global culture, including the component of diversity. The impact of cultural distance in the entrepreneurial mindset and its consequent effect in negotiation behaviour was presented too. Addressing questions about the way individuals perceive, behave and interact allowed the use of interviews for this qualitative research study. In the empirical part of this study it was found that negotiation behaviour differed in terms of how congenial entrepreneurs felt when managing cultural distance, encompassing their performance. It was also acknowledged that after time and effort, some of the personal traits were enhanced while others reduced, allowing for more flexibility and adaptation. Furthermore, depending on the level of trust and shared interests, entrepreneurs determined their attitudinal approach, being adaptive or reactive subject to situational aspects. Additionally, it was found that the acquisition of cultural savvy not necessarily conveyed to more creativity. This experiential learning capability led to the proposition of new ways of behaviour. Likewise, it was proposed that growing cultural intelligence bridge distances, reducing mistrusts and misunderstandings. The capability of building more collaborative relationships allows entrepreneurs to see cultural distance as a cultural perspective instead of as a threat. Therefore it was recommended to focus on proximity rather than distance to better identify and exploit untapped opportunities and better perform when negotiating in whichever cultural conditions.

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The main objective of this work has been to understand the ritual aspect of how private people use the Internet to mourn and honor their intimates in various online environments. The research material was compiled in 2007–2013 through ethnographic and autoethnographic observations in social media applications, online memorial websites, one shared virtual environment (Second Life) and one massive multi-player online role-playing game (World of Warcraft). The research material consists of – in addition to the ethnographic observations – three online surveys with 153 respondents (mainly from Finland, the United States and the United Kingdom). In addition, the researcher conducted 38 longer online interviews (i.e. via email, an avatar). The theoretical framework is derived from ritual theory, hermeneutic-phenomenological anthropology and discourse analysis. The research questions are as follows: Why are death rituals practiced in online environments? How are virtual memorials created in various online environments? What kind of systems of meanings are virtual memorials constructed from? The results indicate that online mourning and honoring is appropriated in addition to the “traditional” offline rituals. In online environments the bereaved can choose, where, when, how and with whom they share their grief and loss. Memorials are created in the web intentionally and unintentionally, where the latter refers inter alia to the Facebook profile of the deceased where his/her intimates gather to mourn and honor immediately after the death. The first refers to intentionally memorialized online places spaces via different service providers. Virtual memorials are a way to construct the identity of the deceased, as well as the bereaved in multiple ways. They also re-enforce and create a sense of communality both privately and publicly, and enable one meaningful online place where all the intimates of the deceased can gather together to mourn and honor despite the geographical or time distances. Tämä väitöstutkimus tarkastelee miten nykyiset kuolemanrituaalit ovat digitalisoituneet verkkoympäristöihin. Tutkimus on suoritettu verkkoetnografisin sekä autoetnografisin menetelmin sosiaalisen median sivustoilla, virtuaalimuistomerkkipalveluissa, yhdestä virtuaalimaailmassa (Second Life) sekä yhdestä reaaliaikaisessa verkkopelissä (World of Warcraft) vuosina 2007–2013. Tutkimusaineisto koostuu etnografisten havainnointien lisäksi kolmesta verkkokyselystä, joissa vastaajia on yhteensä 153 pääasiassa Suomesta, Yhdysvalloista sekä Iso-Britanniasta. Kyselyjen lisäksi tutkija on tehnyt myös 38 laajempaa verkkohaastattelua eri ympäristöissä (esim. sähköposti, avatar virtuaalimaailmassa). Teoreettinen kehys koostuu rituaaliteoriasta, hermeneuttis-phenomenologiasta sekä diskurssianalyysista. Tutkimuskysymykset ovat seuraavat: miksi kuolemanrituaaleja harjoitetaan verkkoympäristöissä, miten virtuaalisia muistomerkkejä luodaan verkkoon, sekä millaisista merkitysjärjestelmistä virtuaaliset muistomerkit muodostuvat? Tutkimustulosten mukaan verkkosureminen ja muistaminen ovat tulleet perinteisten kuolemanrituaalien rinnalle, jolloin sureva itse voi päättää miten, missä, milloin sekä kenen kanssa suree läheistään. Muistomerkkejä verkkoon luodaan suunnitellusti (intentional) sekä suunnittelemattomasti (unintentional), jolloin jälkimmäinen viittaa esimerkiksi edesmenneen Facebook profiiliin, missä hänen läheisensä kokoontuvat muistelemaan ja suremaan välittömästi kuoleman jälkeen. Ensimmäinen taas viittaa suunnitelmalliseen muistomerkin luomiseen, jota varten löytyy useita palveluntarjoajia. Virtuaalimuistomerkit ovat keino rakentaa sekä edesmenneen että surevan identiteettiä, vahvistaa ja luoda yhteisöllisyyttä niin yksityisesti kuin julkisesti, sekä luoda yksi yhteinen aina ja kaikkialta saavutettavissa oleva merkityksellinen paikka verkkoon, missä kaikki läheiset voivat ajasta ja paikasta riippumatta muistella ja surra läheistään.

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Työn tavoitteena oli tuottaa selvitys kohdeyrityksen kotimaan kuljetusten nykytilasta sekä toimenpidesuositus perusteluineen, onko tarpeellista kannustaa nykyisiä kuljetusalihankkijoita hankkimaan uutta kuljetuskalustoa. Lisäksi tutkimuksen tavoitteena oli selvittää ne tilanteet, joissa korkeampien kuormien hyödyntäminen olisi kaikkein kannattavinta kohdeyrityksen kannalta. Tutkimuksen teoriaosiossa käytiin läpi kuljetustoimintojen merkitystä yrityksissä, kerrottiin taustatietoa 1.10.2013 voimaantulleesta mitta- ja massauudistuksesta sekä kuljetuspalveluiden hinnoitteluun liittyviä seikkoja. Työn empiriaosiossa käsiteltiin tutkimukseen valittujen case – tehtaiden kotimaankuljetusten nykytilaa ja tehtaisiin liittyviä kuljetuskustannuslaskelmia tuloksineen, sekä nykytilan mukaisia että aiempaa suurempia sallittuja kuormia hyödynnettäessä. Lisäksi empiriaosiossa esitettiin laskelmiin perustuen toimenpidesuosituksia työn toimeksiantajalle. Työn keskeisin tulos oli, että mitta- ja massauudistusta kannattaa hyödyntää tilanteissa, joissa kuljetettavat määrät ovat mahdollisimmat suuria, välimatkat pitkiä ja joissa kuorma puretaan esim. satamassa. Käytännössä tämä toteutuu Pohjois-Suomesta Etelä-Suomeen suuntautuvissa kuljetuksissa ja se on myös kuljetusyritysten näkökulmasta kannattavin vaihtoehto.

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Identification of low-dimensional structures and main sources of variation from multivariate data are fundamental tasks in data analysis. Many methods aimed at these tasks involve solution of an optimization problem. Thus, the objective of this thesis is to develop computationally efficient and theoretically justified methods for solving such problems. Most of the thesis is based on a statistical model, where ridges of the density estimated from the data are considered as relevant features. Finding ridges, that are generalized maxima, necessitates development of advanced optimization methods. An efficient and convergent trust region Newton method for projecting a point onto a ridge of the underlying density is developed for this purpose. The method is utilized in a differential equation-based approach for tracing ridges and computing projection coordinates along them. The density estimation is done nonparametrically by using Gaussian kernels. This allows application of ridge-based methods with only mild assumptions on the underlying structure of the data. The statistical model and the ridge finding methods are adapted to two different applications. The first one is extraction of curvilinear structures from noisy data mixed with background clutter. The second one is a novel nonlinear generalization of principal component analysis (PCA) and its extension to time series data. The methods have a wide range of potential applications, where most of the earlier approaches are inadequate. Examples include identification of faults from seismic data and identification of filaments from cosmological data. Applicability of the nonlinear PCA to climate analysis and reconstruction of periodic patterns from noisy time series data are also demonstrated. Other contributions of the thesis include development of an efficient semidefinite optimization method for embedding graphs into the Euclidean space. The method produces structure-preserving embeddings that maximize interpoint distances. It is primarily developed for dimensionality reduction, but has also potential applications in graph theory and various areas of physics, chemistry and engineering. Asymptotic behaviour of ridges and maxima of Gaussian kernel densities is also investigated when the kernel bandwidth approaches infinity. The results are applied to the nonlinear PCA and to finding significant maxima of such densities, which is a typical problem in visual object tracking.

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This Licentiate thesis deals with hyperbolic type geometries in planar subdomains. It is known that hyperbolic type distance is always greater in a subdomain than in the original domain. In this work we obtain certain lower estimates for hyperbolic type distances in subdomains in terms of hyperbolic type distances of the original domains. In particular the domains that we consider are cyclic polygons and their circumcircles, sectors and supercircles.

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Industrial production of pulp and paper is an intensive consumer of energy, natural resources, and chemicals that result in a big carbon footprint of the final product. At present companies and industries aspire to calculate their gas emissions into the atmosphere in order to afterwards reduce atmospheric contamination. One of the approaches allowing to increase carbon burden from the pulp and paper manufacture is paper recycling. The general purpose of the current paper is to establish methods of quantifying and minimizing the carbon footprint of paper. The first target of this research is to derive a mathematical relationship between virgin fibre requirements with respect to the amount of recycled paper used in the pulp. One more purpose is to establish a model to be used to clarify the contribution of recycling and transportation to decreasing carbon dioxide emissions. For this study sensitivity analysis is used to investigate the robustness of obtained results. The results of the present study show that an increasing of recycling rate does not always lead to minimizing the carbon footprint. Additionally, we derived that transportation of waste paper throughout distances longer than 5800 km has no sense because the use of that paper will only increase carbon dioxide emissions and it is better to reject recycling at all. Finally, we designed the model for organization of a new supply chain of paper product to a customer. The models were implemented as reusable MATLAB frameworks.

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Toisen jäte on toisen raaka-aine – Kierrätys ja uudelleenvalmistus taloudellisesti ja ekologisesti kestävänä liiketoimintamahdollisuutena Väitöskirjatutkimus tarkastelee kierrätystä ja uudelleenvalmistusta sekä siihen perustuvaa kierrätysliiketoimintaa taloudellisesti ja ekologisesti kestävänä liiketoimintamahdollisuutena. Tässä kestävyys tarkoittaa jätekysymysten ratkaisemista tavalla, joka mahdollistaa kestävän kehityksen periaatteiden mukaisen yhteiskunnan kehittymisen. Jätteisiin liittyvät taloudelliset ja ekolo- giset kysymykset ovat merkittävä yhteiskunnallinen haaste. Tämä luo tarpeen tutkimukselle, jonka lähtökohtana on jätekysymysten moniulotteinen tarkas- telu ja yksittäisen yrityksen toiminnan suhteuttaminen osaksi laajempaa kokonaisuutta. Tässä tutkimuksessa jätteen hyödyntämistä materiaalina lähestytään sekä empiirisesti yrityksen näkökulmasta että teoreettisesti systeemiajattelun tarjoamasta laajemmasta perspektiivistä. Tutkimuksen tavoitteena on ymmär- tää kierrätystä ja uudelleenvalmistusta liiketoimintamahdollisuutena, niiden merkitystä yrityksessä, alueella ja kierrätystaloudessa sekä näiden vuorovai- kutteista suhdetta taloudelliseen ja ekologiseen kestävyyteen nähden. Tutki- muskysymys on tärkeä, koska siihen vastaamalla syvennetään ymmärrystä yrityksissä tapahtuvan kierrätyksen ja uudelleenvalmistuksen merkityksestä kestävämmän yhteiskunnan rakentumisessa. Tutkimuksen teoriaperusta pohjautuu teollisen ekologian kirjallisuuteen ja ekoteollisen kehityksen tutkimukseen. Kierrätysliiketoiminnan kestävyyden tarkastelu rakentuu tutkimuksessa teollisen ekologian ja ekoteollisen kehityk- sen lähtökohtana olevaan win-win-ajatteluun, jonka mukaan hyvä ympäristö- suorituskyky ja hyvä taloudellinen suorituskyky voivat vahvistaa toisiaan. Kierrätysliiketoiminnan teoreettisessa tarkastelussa keskeisiä elementtejä ovat kierrätystalouden malli, teollisen ekologian alueelliset systeemit, ekoteolliset verkostot ja yrityksen rooli teollista ekologiaa soveltavana toimijana. Tutki- muksen keskeisenä kontribuutiona on yritysnäkökulman integroiminen aiem- paa vahvemmin osaksi teollisen ekologian diskursseja. Kierrätysliiketoiminnan taloudelliseen ja ekologiseen kannattavuuteen ja sen myötä kestävyyteen liittyviä kysymyksiä on lähestytty tekemällä yritys- haastatteluja ja hyödyntämällä valmista haastatteluaineistoa. Tutkimusta varten haastattelin 10 kierrätysliiketoimintaa harjoittavaa yritystä vuosina 2007 ja 2008. Tämän lisäksi tutkimuksessa on hyödynnetty Turun ammatti- korkeakoulun ja Turku Science Parkin toteuttamassa RESU-hankkeessa (Kierrätysliiketoiminta ja resurssitehokkuus Varsinais-Suomen vahvuudeksi – RESU) vuosina 2013 ja 2014 kerättyä aineistoa. Hankkeessa haastateltiin yhteensä 25 jätemateriaalia hyödyntävää ja/tai tuottavaa yritystä. Aineistojen analysointimenetelmänä on sisällönanalyysi. Analyysin tulok- sena muodostettiin yhteensä viisi pääteemaa ja 12 alateemaa. Teemat kuvaavat kierrätysliiketoimintaa aiempaa moniulotteisemmin ja näin syventävät ymmär- rystä ilmiön merkityksestä kestävämmän yhteiskunnan rakentumisessa. Teolli- sen ekologian alaan kuuluvat kvalitatiiviset tutkimukset ovat melko harvinai- sia, joten tämän väitöstutkimuksen ilmeisenä vahvuutena on laadullisen tutkimusmenetelmän hyödyntäminen. Tutkimuksen tuloksena voidaan todeta, että kierrätystalouden kehittymistä edistävä kierrätysliiketoiminta on monimuotoista ja sisältää erilaisia liiketoi- mintamahdollisuuksia sekä arvoketjuja. Paikallistuntemus ja keskeinen sijainti jätemateriaalien tuottajien suhteen on tärkeä kriteeri kierrätysliiketoiminnassa, mutta jätemateriaaleja myös kuljetetaan pitkiä matkoja. Paikallisia tai alueelli- sia jätevirtoja hyödyntävä kierrätysliiketoiminta voi tukea alueellista kestä- vyyttä, mutta toisinaan myös keskitetty hyödyntäminen voi olla kestävä vaih- toehto. Yhteistyöverkostot ovat tärkeitä jätemateriaalin laadun ja saatavuuden näkökulmasta. Tutkimus osoittaa, että kierrätysliiketoimintaa harjoittavat yritykset ovat samalla sekä kierrätystalouden käytännön toimeenpanijoita että uuden toimintakulttuurin luojia. Tutkimuksen tulosten perusteella voidaan esittää johtopäätös, että kierrä- tysliiketoiminta on taloudellisesti ja ekologisesti kannattava liiketoimintamah- dollisuus. Win-win-ratkaisut eivät kuitenkaan takaa kierrätysliiketoiminnan kestävyyttä. Kierrätysliiketoiminnan kestävyyden arvioiminen edellyttää laajaa perspektiiviä ja toiminnan vaikutusten suhteuttamista mittakaavaan, ajalliseen ulottuvuuteen, interventioon ja sosiaalisiin kysymyksiin. Teolliseen ekologiaan perustuva kierrätysliiketoiminta luo mahdollisuuksia edistää kestävyyttä, joten tällä perusteella kierrätystä ja uudelleenvalmistusta voidaan pitää kestävänä liiketoimintamahdollisuutena. Avainsanat: kierrätysliiketoiminta, kierrätys, uudelleenvalmistus, systeemiajattelu, teollinen ekologia, ekoteollinen kehitys, kierrätystalous, win-win-ajattelu, kestävyys One company's waste is another's raw material –Recycling and remanufacturing as an economically and environmentally sustainable business opportunity The thesis investigates whether product recycling and remanufacturing can serve as a business opportunity that is economically and ecologically sustaina- ble. In this effort, my idea is to contribute to solving the waste issue in a manner that makes it possible to strive toward sustainable societal develop- ment. The economic and ecological questions associated with waste flows are a significant challenge. The complexity of the issue requires a multidimen- sional approach in which the operation of an individual company is viewed in the context of the larger societal system. In this thesis waste utilization as a resource with value is considered both from an empirical perspective on the firm as well as from a more general viewpoint offered by systems analysis. The objective of the thesis is to under- stand recycling and remanufacturing as a business opportunity. The thesis considers the meaning of recycling and remanufacturing for a single company, for the region the company is located and for the recycling economy. The objective of this study is important for it enhances the understanding of the product recycling and remanufacturing processes that take place within busi- ness organizations and how these processes affect societal sustainable development. The theoretical basis arises from industrial ecology and from the literature on eco-industrial development. The business-economic win-win situation and this vision serve as the basic position from which recycling business is inves- tigated in the thesis. In the theoretical discussion, key elements are recycling economy model, regional and local industrial ecosystems, eco-industrial networks and the role of a company as an actor that applies industrial ecology in practice. The main contribution of this study lies in integrating the company perspective more strongly into the industrial ecology discourses. The recycling business has been studied by conducting interviews in companies and by secondary analysis of an existing interview material. During 2007 and 2008 I made 10 interviews in companies that are active in recycling business. In addition, I used interview material gathered for the project “Recycling business and resource efficiency as the strength of Southwest Finland” (RESU) by Turku University of Applied Sciences and Turku Science Park during the period 2013–2014. This data covers altogether 25 businesses that either utilize and/or produce waste materials. The data has been analyzed using the content analysis method. This process led to the development of 5 main themes and 12 sub-themes. These themes describe the recycling business multi-dimensionally and thus understanding of the phenomenon and its role in building a sustainable society are substantially deepened in this research. In the field of industrial ecology qualitative studies are relatively rare and therefore the qualitative research approach is an evident strength of the thesis. The results show that the recycling business activity supporting recycling economy has diverse dimensions including various business opportunities and diverse value chains. The results show that for waste producers it is important to know the local situational factors and to have a central geographical location. Waste materials are, however, transported over long distances as well. The study indicates that local waste flow utilization can support regional sustainability, while occasionally a more centralized utilization can be sustain- able. Collaboration networks are important to secure the quality and availabil- ity of utilizable waste materials. The thesis demonstrates that the companies practicing recycling business serve simultaneously as actors that implement recycling economy and enhance a new operation culture within the business community. The overall conclusion of the thesis argues that recycling business is a business opportunity that can support both an economically and environmen- tally viable business operation. However, win-win solutions do not secure the sustainability of recycling business. The sustainability evaluation of recycling business requires a holistic systems perspective. The actions undertaken need to be considered with changing spatial and temporal system boundaries, societal intervention and placed in the context of relevant societal issues. Industrial ecology -based recycling business creates opportunities for sustain- ability and thus recycling and remanufacturing present an opportunity for sustainable business. Keywords: Recycling business; Recycling; Remanufacturing, Systems thinking; Industrial ecology; Eco-industrial development; Recycling Economy; Win-Win thinking; Sustainability

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Torrefaction is the partial pyrolysis of wood characterised by thermal degradation of predominantly hemicellulose under inert atmosphere. Torrefaction can be likened to coffee roasting but with wood in place of beans. This relatively new process concept makes wood more like coal. Torrefaction has attracted interest because it potentially enables higher rates of co-firing in existing pulverised-coal power plants and hence greater net CO2 emission reductions. Academic and entrepreneurial interest in torrefaction has sky rocketed in the last decade. Research output has focused on the many aspects of torrefaction – from detailed chemical changes in feedstock to globally-optimised production and supply scenarios with which to sustain EU emission-cutting directives. However, despite its seemingly simple concept, torrefaction has retained a somewhat mysterious standing. Why hasn’t torrefied pellet production become fully commercialised? The question is one of feasibility. This thesis addresses this question. Herein, the feasibility of torrefaction in co-firing applications is approached from three directions. Firstly, the natural limitations imposed by the structure of wood are assessed. Secondly, the environmental impact of production and use of torrefied fuel is evaluated and thirdly, economic feasibility is assessed based on the state of the art of pellet making. The conclusions reached in these domains are as follows. Modification of wood’s chemical structure is limited by its naturally existing constituents. Consequently, key properties of wood with regards to its potential as a co-firing fuel have a finite range. The most ideal benefits gained from wood torrefaction cannot all be realised simultaneously in a single process or product. Although torrefaction at elevated pressure may enhance some properties of torrefied wood, high-energy torrefaction yields are achieved at the expense of other key properties such as heating value, grindability, equilibrium moisture content and the ability to pelletise torrefied wood. Moreover, pelletisation of even moderately torrefied fuels is challenging and achieving a standard level of pellet durability, as required by international standards, is not trivial. Despite a reduced moisture content, brief exposure of torrefied pellets to water from rainfall or emersion results in a high level of moisture retention. Based on the above findings, torrefied pellets are an optimised product. Assessment of energy and CO2-equivalent emission balance indicates that there is no environmental barrier to production and use of torrefied pellets in co-firing. A long product transport distance, however, is necessary in order for emission benefits to exceed those of conventional pellets. Substantial CO2 emission reductions appear possible with this fuel if laboratory milling results carry over to industrial scales for direct co-firing. From demonstrated state-of-the-art pellet properties, however, the economic feasibility of torrefied pellet production falls short of conventional pellets primarily due to the larger capital investment required for production. If the capital investment for torrefied pellet production can be reduced significantly or if the pellet-making issues can be resolved, the two production processes could be economically comparable. In this scenario, however, transatlantic shipping distances and a dry fuel are likely necessary for production to be viable. Based on demonstrated pellet properties to date, environmental aspects and production economics, it is concluded that torrefied pellets do not warrant investment at this time. However, from the presented results, the course of future research in this field is clear.

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Tässä työssä tarkastellaan matkaviestinliikenteen yhteensovittamista Venäjän satelliittimaa-asemien kanssa taajuusalueella 3600 - 4200 MHz. Tutkimusmenetelminä ovat kirjallisuuskatsaus sekä häiriölaskennat. Tulosten perusteella taajuusaluetta ei voida käyttää vapaasti matkaviestinverkoille Suomessa, koska tukiasemat voivat aiheuttaa häiriöitä Venäjällä sijaitseville satelliittimaa-asemille pitkienkin matkojen päästä. Paras ratkaisuvaihtoehto tähän olisi Suomen ja Venäjän välinen sopimus taajuuden käytöstä ja sitä koskevista rajoitteista. Toinen vaihtoehto on käytön suunnittelu ja taajuuskoordinointi tapauskohtaisesti kunkin matkaviestinverkon tukiaseman osalta.

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The escalation in the number of mergers and acquisition transactions involving emerging market firms is a relatively recent phenomenon; as a consequence academic research in such topic is rather limited. The purpose of this research study was to discuss the possible reasons that led the acquisition failure of an emerging multinational firm and an Indonesian player. Extensive theoretical research was performed and it had been achieved, based on this, the finding of a framework that facilitated to understand the way in which the concepts of cultural distances and relate liabilities of foreignness in the process of acquisitions of foreign companies in emerging markets. The theoretical background collects literature related to acquisitions, models of cultural studies between nations and liabilities of foreignness. It has been generated a variety of frameworks that aid to understand the way that the institutional distance and cultural factors together with the concept of liabilities of foreignness can affect the process of market entry of an emerging multinational company to the extent that the best way to stop losing money is to abandon the project. The empirical research consisted of selective semi-structured interviews and an extensive research in available public data on the chosen study case of this research. There were several factors that were identified as the cause of the failure in the market entry of a Mexican multinational firm in Indonesia. The weakness shown by the local government authorities was used by the local community leaders who rioted because of discomfort. These groups were the ones who made the government submit to the extent that the agreements reached at the beginning of the deal were either canceled or modified in a way that favored always the local community. The contributions of this study fall into the knowledge field of emerging multinational firms and market entry process.

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The increasing performance of computers has made it possible to solve algorithmically problems for which manual and possibly inaccurate methods have been previously used. Nevertheless, one must still pay attention to the performance of an algorithm if huge datasets are used or if the problem iscomputationally difficult. Two geographic problems are studied in the articles included in this thesis. In the first problem the goal is to determine distances from points, called study points, to shorelines in predefined directions. Together with other in-formation, mainly related to wind, these distances can be used to estimate wave exposure at different areas. In the second problem the input consists of a set of sites where water quality observations have been made and of the results of the measurements at the different sites. The goal is to select a subset of the observational sites in such a manner that water quality is still measured in a sufficient accuracy when monitoring at the other sites is stopped to reduce economic cost. Most of the thesis concentrates on the first problem, known as the fetch length problem. The main challenge is that the two-dimensional map is represented as a set of polygons with millions of vertices in total and the distances may also be computed for millions of study points in several directions. Efficient algorithms are developed for the problem, one of them approximate and the others exact except for rounding errors. The solutions also differ in that three of them are targeted for serial operation or for a small number of CPU cores whereas one, together with its further developments, is suitable also for parallel machines such as GPUs.