937 resultados para Shifting Powers
Resumo:
Today the limitedness of fossil fuel resources is clearly realized. For this reason there is a strong focus throughout the world on shifting from fossil fuel based energy system to biofuel based energy system. In this respect Finland with its proven excellent forestry capabilities has a great potential to accomplish this goal. It is regarded that one of the most efficient ways of wood biomass utilization is to use it as a feedstock for fast pyrolysis process. By means of this process solid biomass is converted into liquid fuel called bio-oil which can be burnt at power plants, used for hydrogen generation through a catalytic steam reforming process and as a source of valuable chemical compounds. Nowadays different configurations of this process have found their applications in several pilot plants worldwide. However the circulating fluidized bed configuration is regarded as the one with the highest potential to be commercialized. In the current Master’s Thesis a feasibility study of circulating fluidized bed fast pyrolysis process utilizing Scots pine logs as a raw material was conducted. The production capacity of the process is 100 000 tonne/year of bio-oil. The feasibility study is divided into two phases: a process design phase and economic feasibility analysis phase. The process design phase consists of mass and heat balance calculations, equipment sizing, estimation of pressure drops in the pipelines and development of plant layout. This phase resulted in creation of process flow diagrams, equipment list and Microsoft Excel spreadsheet that calculates the process mass and heat balances depending on the bio-oil production capacity which can be set by a user. These documents are presented in the current report as appendices. In the economic feasibility analysis phase there were at first calculated investment and operating costs of the process. Then using these costs there was calculated the price of bio-oil which is required to reach the values of internal rate of return of 5%, 10%, 20%, 30%, 40%, and 50%.
Resumo:
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.
Resumo:
A direct procedure for the evaluation of imperfection sensitivity in bifurcation problems is presented. The problems arise in the context of the general theory of elastic stability for discrete structural systems, in which the energy criterion of stability of structures and the total potential energy formulation are employed. In cases of bifurcation buckling the sensitivity of the critical load with respect to an imperfection parameter e is singular at the state given by epsilon =0, so that, a regular perturbation expansion of the solution is not possible. In this work we describe a direct procedure to obtain the relations between the critical loads, the generalized coordinates at the critical state, the eigenvector, and the amplitude of the imperfection, using singular perturbation analysis. The expansions are assumed in terms of arbitrary powers of the imperfection parameter, so that both exponents and coefficients of the expansion are unknown. The solution of the series exponents is obtained by searching the least degenerate solution. The formulation is here applied to asymmetric bifurcations, for which explicit expressions of the coefficients are obtained. The use of the method is illustrated by a simple example, which allows consideration of the main features of the formulation.
Resumo:
Otsikon mukaisesti työ keskittyy venäläisten sotilaallisiin näkemyksiin. Arktista tutkimusta on sinällään tehty ja tehdään paljon, mutta todennäköisesti venäläistä sotilasajattelua mainitusta aiheesta ei ole tarkasteltu suomen kielellä. Työn aineisto on lähes kokonaan venäjänkielistä ja tutkittu aineisto koostuu kirjoittajista, joita – kuten Venäjällä sanotaan – pidetään alansa auktoriteetteina. Lähteet ovat julkisia.
Resumo:
I det här arbetet utformades en utvecklings- och investeringsplan för automatisk trafiksäkerhetsövervakning för åren 2011-2015 för landsvägsnätet i Egentliga Finland och Satakunta. Planen innehåller analys av den nuvarande verksamhetsmodellen och förslag hur verksamhetsmodellen kunde förbättras samt förslag om vilka vägavsnitt som ska få automatisk övervakning och vilka projekt som ska prioriteras under åren 2011-2015. Vidare beskrivs i planen den automatiska övervakningsteknik och verksamhetsmodell som används i Sverige samt åtgärdsförslag för att öka den automatiska trafikövervakningens acceptans. Den nuvarande verksamhetsmodellen och behovet av att utveckla den automatiska trafikövervakningen har utvärderats på basis av intervjuer med experter. Experterna ansåg att den nuvarande verksamhetsmodellen i huvudsak är funktionell och effektiv, eftersom man med relativt små kostnader har uppnått effektiva resultat. Den automatiska trafikövervakningen måste dock fortfarande utvecklas och Sveriges verksamhetsmodell ansågs vara en bra förebild och ett gott exempel. De viktigaste utvecklingsområdena ansågs vara utveckling av tekniken, snabbare informationsbehandling och automatisering, vilket skulle öka polisens resurser att verkställa övervakningen. Vägavsnitten som ska få automatisk övervakning under åren 2011-2015 prioriterades främst på basis av olycksfrekvens, antal olyckor, Tarva-beräkningsresultat, hastighetsdata och trafikmängder. Av olycksstatistiken har man främst uppmärksammat personskadeolyckor. Tarva-beräkningarna användes också för att utvärdera den automatiska trafikövervakningens inverkan och effektivitet. Enligt de intervjuade experterna är öppenhet kring övervakningen, synlig övervakningsapparatur och kontinuerlig informationsförmedling bland de viktigaste sätten att öka acceptansen. Genom att informera för man fram systemets fördelar och dess betydelse för trafiksäkerheten. Att förändra övervakningskamerans varumärke till säkerhetskamera enligt Sveriges modell ansågs även vara bra. I detta arbete presenteras en plan för att utveckla acceptansen för automatisk trafiksäkerhetsövervakning.
Resumo:
Concerns about the sustainability of large-scale, direct-drilled RR-soybeans (Glycine max), and RR-maize (Zea mays) under monoculture in central Argentina are growing steadily. An experiment was conducted during three consecutive years to determine the effects of crops and systems (monocultures and strips) and herbicide strategy on weed density, population rate of change (l), b community diversity (H´), crop yields and Land Equivalent Ratio (LER). Not only crops but also crop systems differentially influenced weed densities along their growth and development. For crop harvests, weed densities increased in both maize crop systems as compared to in the one for soybeans, but the lowest increase occurred in soybean strips. Differences were leveled by both herbicide strategies, which achieved 73% efficacy during the critical periods in both crops. l of annual monocotyledonous increased, thus shifting the weed community composition. Species richness and H´ were not affected by crop systems, but both herbicide strategies, particularly POST, either in soybeans in monoculture or in maize strips, significantly enhanced H´. Crop yields significantly increased in the maize-strip system with POST (Year 1) or PRE (Years 2 and 3) strategies, thus increasing LER above 1. Herbicide Environmental Load treatments fall within very low or low field use rating.
Resumo:
Organisatorista oppimista tapahtuu kaikissa organisaatioissa. Muuttuvassa toimintaympäristössä ja kovenevassa kilpailussa sellaiset organisaatiot pärjäävät parhaiten, jotka pystyvät oppimaan ja kehittämään toimintaa muita nopeammin. Tämän työn tavoitteena on tunnistaa, miten ja millaista organisatorista oppimista Lahden diakonian instituutissa tapahtuu ja miten se vaikuttaa opetuksen laatuun. Laatua lähestytään kahdesta eri näkökulmasta. Näitä ovat opetusministeriön laatusuositukset ja rahoitukseen vaikuttavat mittarit sekä opettajien itse laadukkaalle työlle määrittelemät kriteerit. Empiirinen osuus toteutetaan puolistrukturoiduin haastatteluin ja tutkimusmenetelmänä käytetään tapaustutkimusta. Haastateltavana on kuusi Lahden diakonian instituutin opettajaa. Tutkimuksen mukaan Lahden diakonian instituutissa tapahtuu organisatorista oppimista, mutta se ei ole riittävää, systemaattista tai tavoitteellista. Suurimmat esteet ovat sille varattujen resurssien puuttuminen, opettajien työn itsenäinen luonne ja yhteistyön vähyys, kiire sekä päätösvallan puuttuminen. Tutkimus kuitenkin osoittaa, että organisatorisella oppimisella voidaan vaikuttaa parantavasti myös opetuksen laatuun esimerkiksi uusien toimintamallien ja resurssien paremman kohdentamisen kautta.
Resumo:
Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
Resumo:
Tämän tutkimuksen tavoitteena on selvittää, voidaanko yritysten tilinpäätöstiedoista löytää sellaisia muuttujia, jotka pystyvät ennustamaan yritysten konkursseja ja onko yrityksen kannattavuudella, vakavaraisuudella ja maksuvalmiudella kaikilla yhtä suuri merkitys konkurssin ennustamisessa. Lisäksi tavoitteena on verrata mitkä eri muuttujat selittävät konkurssia eri vuosina. Tutkimus toteutetaan luomalla viidelle vuodelle ennen konkurssia ennustusmallit käyttäen logistista regressiota. Tutkimus on rajattu koskemaan suomalaisia pieniä ja keskisuuria osakeyhtiöitä. Tutkimuksessa käytetty aineisto koostuu vuonna 2012 konkurssiin menneistä yrityksistä ja näille satunnaisotannalla valituista toimivista vertailuyrityksistä. Tutkimuksesta on rajattu pois nuoret, alle neljä vuotta toimineet yritykset, koska näiden konkurssiprosessit eroavat jo pidemmän aikaa toimineiden yritysten konkursseista.
Resumo:
Concepts, models, or theories that end up shaping practices, whether those practices fall in the domains of science, technology, social movements, or business, always emerge through a change in language use. First, communities begin to talk differently, incorporating new vocabularies (Rorty, 1989), in their narratives. Whether the community’s new narratives respond to perceived anomalies or failures of the existing ones (Kuhn, 1962) or actually reveal inadequacies by addressing previously unrecognized practices (Fleck, 1979; Rorty, 1989) is less important here than the very phenomena that they introduce differences. Then, if the new language proves to be useful, for example, because it helps the community solve a problem or create a possibility that existing narratives do not, the new narrative will begin circulating more broadly throughout the community. If other communities learn of the usefulness of these new narratives, and find them sufficiently persuasive, they may be compelled to test, modify, and eventually adopt them. Of primary importance is the idea that a new concept or narrative perceived as useful is more likely to be adopted. We can expect that business concepts emerge through a similar pattern. Concepts such as “competitive advantage,” “disruption,” and the “resource based view,” now broadly known and accepted, were each at some point first introduced by a community. This community experimented with the concepts they introduced and found them useful. The concept “competitive advantage,” for example, helped researchers better explain why some firm’s outperformed others and helped practitioners more clearly understand what choices to make to improve the profit and growth prospects of their firms. The benefits of using these terms compelled other communities to consider, apply, and eventually adopt them as well. Were these terms not viewed as useful, they would not likely have been adopted. This thesis attempts to observe and anticipate new business concepts that may be emerging. It does so by seeking to observe a community of business practitioners that are using different language and appear to be more successful than a similar community of practitioners that are have not yet begun using this different language as extensively. It argues that if the community that is adopting new types of narratives is perceived as being more successful, their success will attract the attention of other communities who may then seek to adopt the same narratives. Specifically, this thesis compares the narratives used by a set of firms that are considered to be performing well (called Winners) with those of set of less-successful peers (called Losers). It does so with the aim of addressing two questions: - How do the strategic narratives that circulate within “winning” companies and their leaders differ from those circulating within “losing” companies and their leaders? - Given the answer to the first question: what new business strategy concepts are likely to emerge in the business community at large? I expected to observe “winning” companies shifting their language, abandoning an older set of narratives for newer ones. However the analysis indicates a more interesting dynamic: “winning” companies adopt the same core narratives as their “losing” peers with equal frequency yet they go beyond these. Both “winners” and “losers” seem to pursue economies of scale, customer captivity, best practices, and securing preferential access to resources with similar vigor. But “winners” seem to go further, applying three additional narratives in their pursuits of competitive advantage. They speak of coordinating what is uncoordinated, adopting what this thesis calls “exchanging the role of guest for that of host,” and “forcing a two-front battle” more frequently than their “loser” peers. Since these “winning” companies are likely perceived as being more successful, the unique narratives they use are more likely to be emulated and adopted. Understanding in what ways winners speak differently, therefore, gives us a glimpse into the possible future evolution of business concepts.
Resumo:
The role of catecholamines in the distribution of intrarenal blood flow and in single-nephron glomerular filtration rate (SNGFR) was evaluated in anesthetized Wistar rats by the Hanssen technique. Epinephrine (EPI) and norepinephrine (NOR) were infused to produce elevations of 20-30 mmHg in mean arterial pressure. Superficial and juxtamedullary nephron perfusion and filtration were determined by the presence of Prussian blue dye. In the control group, 100% of the nephrons presented a homogeneous pattern of perfusion and filtration. In contrast, a heterogeneous distribution of the dye was found even in the larger arteries (arciform and radial), indicating variable perfusion and filtration in both superficial and juxtamedullary nephrons. The effects of EPI and NOR were also evaluated in the superficial cortex by the micropuncture technique in two additional groups of Munich-Wistar rats. Mean SNGFR was 27% and 54% lower in the EPI- and NOR-treated groups, respectively. No change in mean intraglomerular hydraulic pressure was observed after EPI or NOR infusion in spite of a highly scattered pattern, indicating an important variability in perfusion along the superficial cortex, and/or different sensitivity of the pre- and post-glomerular arterioles. The present data suggest that EPI and NOR may affect intrarenal hemodynamics by modifying perfusion and filtration in both superficial and juxtamedullary glomeruli and not by shifting blood flow from superficial to juxtamedullary nephrons. The heterogeneous pattern of perfusion was a consequence of differential vasoconstriction along the intrarenal arteries, probably due to different density and/or sensitivity of the adrenergic receptor subtypes present in the intrarenal vascular tree.
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We investigated the effects of aerobic training on the efferent autonomic control of heart rate (HR) during dynamic exercise in middle-aged men, eight of whom underwent exercise training (T) while the other seven continued their sedentary (S) life style. The training was conducted over 10 months (three 1-h sessions/week on a field track at 70-85% of the peak HR). The contribution of sympathetic and parasympathetic exercise tachycardia was determined in terms of differences in the time constant effects on the HR response obtained using a discontinuous protocol (4-min tests at 25, 50, 100 and 125 watts on a cycle ergometer), and a continuous protocol (25 watts/min until exhaustion) allowed the quantification of the parameters (anaerobic threshold, VO2 AT; peak O2 uptake, VO2 peak; power peak) that reflect oxygen transport. The results obtained for the S and the T groups were: 1) a smaller resting HR in T (66 beats/min) when compared to S (84 beats/min); 2) during exercise, a small increase in the fast tachycardia (D0-10 s) related to vagal withdrawal (P<0.05, only at 25 watts) was observed in T at all powers; at middle and higher powers a significant decrease (P<0.05 at 50, 100 and 125 watts) in the slow tachycardia (D1-4 min) related to a sympathetic-dependent mechanism was observed in T; 3) the VO2 AT (S = 1.06 and T = 1.33 l/min) and VO2 peak (S = 1.97 and T = 2.47 l/min) were higher in T (P<0.05). These results demonstrate that aerobic training can induce significant physiological adaptations in middle-aged men, mainly expressed as a decrease in the sympathetic effects on heart rate associated with an increase in oxygen transport during dynamic exercise.
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The objective of this research is to demonstrate the use of Lean Six Sigma methodology in a manufacturing lead time improvement project. Moreover, the goal is to develop working solutions for the target company to improve its manufacturing lead time. The theoretical background is achieved through exploring the literature of Six Sigma, Lean and Lean Six Sigma. The development will be done in collaboration with the related stakeholders, by following the Lean Six Sigma improvement process DMAIC and by analyzing the process data from the target company. The focus of this research is in demonstrating how to use Lean Six Sigma improvement process DMAIC in practice, rather than in comparing Lean Six Sigma to other improvement methodologies. In order to validate the manufacturing system’s current state, improvement potential and solutions, statistical tools such as linear regression analysis were used. This ensured that all the decisions were as heavily based on actual data as possible. As a result of this research, a set of solutions were developed and implemented in the target company. These solutions included batch size reduction, bottleneck shift, first-in first-out queuing and shifting a data entry task from production planners to line workers. With the use of these solutions, the target company was able to reduce its manufacturing lead time by over one third.
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Biopolttoaineilla on tärkeä rooli tulevaisuuden energiahuollossa. Biopolttoaineiden käyttöä pyritäänkin lisäämään monin keinoin. Ensimmäisen sukupolven biopolttoaineet ovat jo olleet aikansa markkinoilla ja toisen sukupolven polttoaineet ovat saapumassa markkinoille. Tässä työssä tutkitaan eri biopolttoaine vaihtoehtoja ensimmäisestä toiseen sukupolveen sekä tutkitaan niiden käytön ongelmia. Biopolttoaineiden käyttö on lisääntynyt huomattavasti viime vuosien aikoina, jonka myötä on tullut esiin monia ongelmia. Ongelmia aiheuttavat niin ilmastolliset, taloudelliset, teknologiset kuin valtapoliittiset asiat.
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Toimittajien arviointi, luokittelu sekä suorituskyvyn mittaaminen ovat nousseet yhdeksi merkittäväksi tekijäksi yritysten pyrkiessä kilpailukyvyn parantamiseen. Sisäisten prosessien kehittämisen lisäksi painopistettä ollaan siirtämässä yhä enemmän toimittajien koordinointiin ja jopa heidän omien prosessiensa kehittämiseen. Globaalit markkinat ovat mahdollistaneet uusien toimittajien löytämisen, minkä seurauksena toimittajamäärä on kasvanut rajusti. Jatkuvan resurssien kiristämisen takia toimittajien kanssa tehtävän yhteistyön jatkuva seuranta ei kuitenkaan ole mahdollista. Yritysten tulee löytää juuri ne potentiaalisimmat toimittajat, joiden kanssa tehty yhteistyö tuottaa parhaimmat tulokset. Tutkimuksen tavoitteena on selvittää, kuinka toimittajayhteistyötä voitaisiin kehittää kokonaisvaltaisesti sekä tilaajan että toimittajan näkökulmasta. Tutkimuksen teoriaosuudessa keskitytään toimittajien arviointiin, luokitteluun ja suorituskyvyn mittaamiseen. Tutkimuksen empiriaosuus muodostuu teemahaastatteluista, jossa haastateltiin sekä toimittajia että tilaajia yhteistyön tekemisen näkökulmasta. Saatuja vastauksia analysoitiin aiempaa kirjallisuutta vastaan. Tuloksena esitetään kohdeyritykselle malli, jonka avulla voidaan löytää potentiaalisimmat toimittajat ja auttaa kehittämään yhteistyötä heidän kanssaan. Tutkimuksen merkittävimpinä havaintoina voidaan pitää liikevaihdon osuuden merkitystä kehitysaktiivisuuteen sekä ei-taloudellisten mittareiden huomioon ottamista.