994 resultados para Cumulative Prospect Theory
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This paper is a historical companion to a previous one, in which it was studied the so-called abstract Galois theory as formulated by the Portuguese mathematician Jos Sebastio e Silva (see da Costa, Rodrigues (2007)). Our purpose is to present some applications of abstract Galois theory to higher-order model theory, to discuss Silva's notion of expressibility and to outline a classical Galois theory that can be obtained inside the two versions of the abstract theory, those of Mark Krasner and of Silva. Some comments are made on the universal theory of (set-theoretic) structures.
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ABSTRACT When Hume, in the Treatise on Human Nature, began his examination of the relation of cause and effect, in particular, of the idea of necessary connection which is its essential constituent, he identified two preliminary questions that should guide his research: (1) For what reason we pronounce it necessary that every thing whose existence has a beginning should also have a cause and (2) Why we conclude that such particular causes must necessarily have such particular effects? (1.3.2, 14-15) Hume observes that our belief in these principles can result neither from an intuitive grasp of their truth nor from a reasoning that could establish them by demonstrative means. In particular, with respect to the first, Hume examines and rejects some arguments with which Locke, Hobbes and Clarke tried to demonstrate it, and suggests, by exclusion, that the belief that we place on it can only come from experience. Somewhat surprisingly, however, Hume does not proceed to show how that derivation of experience could be made, but proposes instead to move directly to an examination of the second principle, saying that, "perhaps, be found in the end, that the same answer will serve for both questions" (1.3.3, 9). Hume's answer to the second question is well known, but the first question is never answered in the rest of the Treatise, and it is even doubtful that it could be, which would explain why Hume has simply chosen to remove any mention of it when he recompiled his theses on causation in the Enquiry concerning Human Understanding. Given this situation, an interesting question that naturally arises is to investigate the relations of logical or conceptual implication between these two principles. Hume seems to have thought that an answer to (2) would also be sufficient to provide an answer to (1). Henry Allison, in his turn, argued (in Custom and Reason in Hume, p. 94-97) that the two questions are logically independent. My proposal here is to try to show that there is indeed a logical dependency between them, but the implication is, rather, from (1) to (2). If accepted, this result may be particularly interesting for an interpretation of the scope of the so-called "Kant's reply to Hume" in the Second Analogy of Experience, which is structured as a proof of the a priori character of (1), but whose implications for (2) remain controversial.
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In this article I intend to show that certain aspects of A.N. Whitehead's philosophy of organism and especially his epochal theory of time, as mainly exposed in his well-known work Process and Reality, can serve in clarify the underlying assumptions that shape nonstandard mathematical theories as such and also as metatheories of quantum mechanics. Concerning the latter issue, I point to an already significant research on nonstandard versions of quantum mechanics; two of these approaches are chosen to be critically presented in relation to the scope of this work. The main point of the paper is that, insofar as we can refer a nonstandard mathematical entity to a kind of axiomatical formalization essentially 'codifying' an underlying mental process indescribable as such by analytic means, we can possibly apply certain principles of Whitehead's metaphysical scheme focused on the key notion of process which is generally conceived as the becoming of actual entities. This is done in the sense of a unifying approach to provide an interpretation of nonstandard mathematical theories as such and also, in their metatheoretical status, as a formalization of the empirical-experimental context of quantum mechanics.
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Min avhandling behandlar hur oordnade material leder elektrisk strm. Bland materialen som studeras finns ledande polymerer, d.v.s. plaster som leder strm, och mer allmnt organiska halvledare. Av de hr materialen har man kunnat bygga elektroniska komponenter, och man hoppas p att kunna trycka hela kretsar av organiska material. Fr de hr tillmpningarna r det viktigt att frst hur materialen sjlva leder elektrisk strm. Termen oordnade material syftar p material som saknar kristallstruktur. Oordningen gr att elektronernas tillstnd blir lokaliserade i rummet, s att en elektron i ett visst tillstnd r begrnsad t.ex. till en molekyl eller ett segment av en polymer. Det hr kan jmfras med kristallina material, dr ett elektrontillstnd r utspritt ver hela kristallen (men i stllet har en vldefinierad rrelsemngd). Elektronerna (eller hlen) i det oordnade materialet kan rra sig genom att tunnelera mellan de lokaliserade tillstnden. Utgende frn egenskaperna fr den hr tunneleringsprocessen, kan man bestmma transportegenskaperna fr hela materialet. Det hr r utgngspunkten fr den s kallade hopptransportmodellen, som jag har anvnt mig av. Hopptransportmodellen innehller flera drastiska frenklingar. Till exempel betraktas elektrontillstnden som punktformiga, s att tunneleringssannolikheten mellan tv tillstnd endast beror p avstndet mellan dem, och inte p deras relativa orientation. En annan frenkling r att behandla det kvantmekaniska tunneleringsproblemet som en klassisk process, en slumpvandring. Trots de hr grova approximationerna visar hopptransportmodellen nd mnga av de fenomen som upptrder i de verkliga materialen som man vill modellera. Man kan kanske sga att hopptransportmodellen r den enklaste modell fr oordnade material som fortfarande r intressant att studera. Man har inte hittat exakta analytiska lsningar fr hopptransportmodellen, drfr anvnder man approximationer och numeriska metoder, ofta i form av datorberkningar. Vi har anvnt bde analytiska metoder och numeriska berkningar fr att studera olika aspekter av hopptransportmodellen. En viktig del av artiklarna som min avhandling baserar sig p r att jmfra analytiska och numeriska resultat. Min andel av arbetet har frmst varit att utveckla de numeriska metoderna och applicera dem p hopptransportmodellen. Drfr fokuserar jag p den hr delen av arbetet i avhandlingens introduktionsdel. Ett stt att studera hopptransportmodellen numeriskt r att direkt utfra en slumpvandringsprocess med ett datorprogram. Genom att fra statisik ver slumpvandringen kan man berkna olika transportegenskaper i modellen. Det hr r en s kallad Monte Carlo-metod, eftersom sjlva berkningen r en slumpmssig process. I stllet fr att flja rrelsebanan fr enskilda elektroner, kan man berkna sannolikheten vid jmvikt fr att hitta en elektron i olika tillstnd. Man stller upp ett system av ekvationer, som relaterar sannolikheterna fr att hitta elektronen i olika tillstnd i systemet med fldet, strmmen, mellan de olika tillstnden. Genom att lsa ekvationssystemet fs sannolikhetsfrdelningen fr elektronerna. Frn sannolikhetsfrdelningen kan sedan strmmen och materialets transportegenskaper berknas. En aspekt av hopptransportmodellen som vi studerat r elektronernas diffusion, d.v.s. deras slumpmssiga rrelse. Om man betraktar en samling elektroner, s sprider den med tiden ut sig ver ett strre omrde. Det r knt att diffusionshastigheten beror av elfltet, s att elektronerna sprider sig fortare om de pverkas av ett elektriskt flt. Vi har underskt den hr processen, och visat att beteendet r vldigt olika i endimensionella system, jmfrt med tv- och tredimensionella. I tv och tre dimensioner beror diffusionskoefficienten kvadratiskt av elfltet, medan beroendet i en dimension r linjrt. En annan aspekt vi studerat r negativ differentiell konduktivitet, d.v.s. att strmmen i ett material minskar d man kar spnningen ver det. Eftersom det hr fenomenet har uppmtts i organiska minnesceller, ville vi underska om fenomenet ocks kan uppst i hopptransportmodellen. Det visade sig att det i modellen finns tv olika mekanismer som kan ge upphov till negativ differentiell konduktivitet. Dels kan elektronerna fastna i fllor, tervndsgrnder i systemet, som r sdana att det r svrare att ta sig ur dem d elfltet r stort. D kan elektronernas medelhastighet och drmed strmmen i materialet minska med kande elflt. Elektrisk vxelverkan mellan elektronerna kan ocks leda till samma beteende, genom en s kallad coulombblockad. En coulombblockad kan uppst om antalet ledningselektroner i materialet kar med kande spnning. Elektronerna repellerar varandra och ett strre antal elektroner kan leda till att transporten blir lngsammare, d.v.s. att strmmen minskar.
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Lectio praecursoria Tampereen yliopistossa 17.8.2010.
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Tyn tavoitteena oli luoda tykalu kestomagneettikoneiden roottoreiden vsymisen analysointia varten. Tykalu toteutettiin siten, ett siihen voidaan liitt oikeasta koneesta mitattu kuormitusdata, sek tarvittavat materiaalitiedot. Kuormitusdata muunnetaan tykalussa jnnityshistoriaksi kyttmll elementtimenetelmn avulla laskettavaa skaalauskerrointa. Kestoin laskemiseen analyysitykalu kytt jnnitykseen perustuvaa menetelm sek rainflowmenetelm ja Palmgren-Minerin kumulatiivista vauriosnt. Lisksi tykalu tekee tutkittavalle tapaukselle Smithin vsymislujuuspiirroksen. Edell mainittujen menetelmien lisksi tyn teoriaosassa esiteltiin vsymisanalyysimenetelmist mys paikalliseen venymn perustuva menetelm sek murtumismekaniikka. Nm menetelmt jivt monimutkaisuutensa vuoksi toteuttamatta tykalussa. Vsymisanalyysitykalulla laskettiin kestoit kahdelle esimerkkitapaukselle. Kummassakin tapauksessa saatiin tulokseksi retn kestoik, mutta aksiaalivuokoneen roottorin dynaaminen varmuus oli pieni. Vaikka tulokset vaikuttavat jrkevilt, ne olisi viel hyv verifioida esimerkiksi kaupallisen ohjelmiston avulla tyden varmuuden saamiseksi.
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The application of the Extreme Value Theory (EVT) to model the probability of occurrence of extreme low Standardized Precipitation Index (SPI) values leads to an increase of the knowledge related to the occurrence of extreme dry months. This sort of analysis can be carried out by means of two approaches: the block maxima (BM; associated with the General Extreme Value distribution) and the peaks-over-threshold (POT; associated with the Generalized Pareto distribution). Each of these procedures has its own advantages and drawbacks. Thus, the main goal of this study is to compare the performance of BM and POT in characterizing the probability of occurrence of extreme dry SPI values obtained from the weather station of Ribeiro Preto-SP (1937-2012). According to the goodness-of-fit tests, both BM and POT can be used to assess the probability of occurrence of the aforementioned extreme dry SPI monthly values. However, the scalar measures of accuracy and the return level plots indicate that POT provides the best fit distribution. The study also indicated that the uncertainties in the parameters estimates of a probabilistic model should be taken into account when the probability associated with a severe/extreme dry event is under analysis.
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For number of reasons social responsibility in corporations has become a more essential part of business operations than before. Corporate social responsibility (CSR) is dealt with different means and aspects but the overall effects it has on organisations performance, communication and underline actions is indisputable. The thesis describes corporate social responsibility and the main objective was to observe how corporate social responsibility has developed in our case company with answering to main research question how CSR reporting has evolved in UPM-Kymmene Oyj? In addition following questions were also addressed: Is there a monetary value of CSR? What does proficient CSR report consist of? What does corporate social responsibility consist of? Qualitative research method, content analysis to be precise, was chosen and excessive literature study performed to find the theoretical back ground to perform the empirical part of the study. Data for the empirical part was collected from UPM-Kymmene Oyj financial data and annual reports. The study shows that UPM-Kymmene Oyj engagement to CSR and reporting of CSR matter have improved due time but still few managerial implications could be found. UPM-Kymmene Oyj economic key figures are only building shareholder value and stakeholders are identified in very general level. Also CSR data is scattered all over the annual report which causes problems to readers. The scientific importance of this thesis arises from the profound way CSR has been addressed in a holistic manner. Thus it is giving a good basis to understand the underlying reasons of CSR from society towards the organisation and vice versa.
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After decades of mergers and acquisitions and successive technology trends such as CRM, ERP and DW, the data in enterprise systems is scattered and inconsistent. Global organizations face the challenge of addressing local uses of shared business entities, such as customer and material, and at the same time have a consistent, unique, and consolidate view of financial indicators. In addition, current enterprise systems do not accommodate the pace of organizational changes and immense efforts are required to maintain data. When it comes to systems integration, ERPs are considered closed and expensive. Data structures are complex and the out-of-the-box integration options offered are not based on industry standards. Therefore expensive and time-consuming projects are undertaken in order to have required data flowing according to business processes needs. Master Data Management (MDM) emerges as one discipline focused on ensuring long-term data consistency. Presented as a technology-enabled business discipline, it emphasizes business process and governance to model and maintain the data related to key business entities. There are immense technical and organizational challenges to accomplish the single version of the truth MDM mantra. Adding one central repository of master data might prove unfeasible in a few scenarios, thus an incremental approach is recommended, starting from areas most critically affected by data issues. This research aims at understanding the current literature on MDM and contrasting it with views from professionals. The data collected from interviews revealed details on the complexities of data structures and data management practices in global organizations, reinforcing the call for more in-depth research on organizational aspects of MDM. The most difficult piece of master data to manage is the local part, the attributes related to the sourcing and storing of materials in one particular warehouse in The Netherlands or a complex set of pricing rules for a subsidiary of a customer in Brazil. From a practical perspective, this research evaluates one MDM solution under development at a Finnish IT solution-provider. By means of applying an existing assessment method, the research attempts at providing the company with one possible tool to evaluate its product from a vendor-agnostics perspective.
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Kirjallisuusarvostelu
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Tutkimuksen tarkoituksena on laadullisin menetelmin syvent tietoa tyikisten (2860-vuotiaiden) suomalaisten kvantitatiivisesti mitatun koherenssin tunteen takana olevista tekijist. Tutkimuksella halutaan tuottaa aineistolhtisesti tietoa siit, mitk ksitteet kuvaavat tutkittavien kerrottujen elmnkokemusten kautta selvitetty koherenssin tunnetta ja samalla lismn ymmrryst Antonovskyn salutogeenisesta teoreettisesta mallista. Tutkimukseen osallistuneet olivat Health and Social Support tutkimukseen vuosina 1998 ja 2003 osallistuneita. Koko kyseinen tutkimusotos edusti vuonna 1998 2024, 3034, 4044 ja 5054 -vuotiasta Suomen vest. Tutkimuksen metodina kytettiin glaserilaista grounded theory -metodologiaa. Tutkimuksen aineistonkeruu toteutettiin kolmessa eri vaiheessa. Ensimmisess vaiheessa haastateltiin 27 tutkittavaa. Toisessa vaiheessa haastateltavilta kerttiin lisaineistoa kirjallisesti. Kahdeksan vastasi thn pyyntn. Kolmannessa vaiheessa haastateltiin seitsem. Haastattelujen yhteydess haastateltavat tyttivt koherenssin tunteen mittarin (13-osainen). Aineisto analysoitiin koherenssipisteiden mukaisesti kolmena eri aineistona. Tulokseksi saatiin substantiivinen teoria. Tutkimuksen tuloksena kuvattiin sosiaalinen perusprosessi, joka nimitettiin Elmn kokonaisuudeksi tss hetkess. Sosiaalisen perusprosessin sisll on typologia. Jokaisesta koherenssipisteryhmst muodostettiin oma typologia. Kukin typologia sislsi nelj tyyppi. Sosiaalisen perusprosessin vaiheet olivat: ehdot tmn hetken taustalla, elminen ehtojen varassa ja uusia luoden (tietynlainen ihminen, elminen tss hetkess, kokonaisnkemys elmst) sek jatkaminen ehtojen varassa ja uusia luoden. Typologiat ovat nimeltn ehet, prjvt ja sinnittelijt. Haastateltavien kokemuksia ei analyysivaiheessa pyritty liittmn tiettyyn kontekstiin, vaan ne liittyivt toimintaan ja kyttytymiseen. Tulosten tarkasteluvaiheessa tehtiin kuitenkin lyhyt kuvaus elmnkulkututkimuksesta sek sosiaalisesta ja kulttuurisesta ympristst. Tutkimustulokset ovat kuvailevia ja niiden perusteella saadaan viitteit siit, millaiset asiat ovat yhteydess koherenssin tunteeseen ja mill tavalla yhteys rakentuu. Saatu substantiivinen teoria on ptev tss aineistossa. Tulokset noudattelevat Antonovskyn salutogeenista teoreettista mallia silt osin, ett mit korkeammat koherenssipisteet olivat, sit enemmn typologiassa oli eheytt lisvi tekijit. Eheys tuo elmn henkist liikkumavaraa, jota typologian tyypit (rakentava, ilmavasti elv, elmnmynteinen, juureva realisti) ilmentvt. Typologioiden kuvauksista voidaan lukea, ett kaikissa tyypeiss kuvataan vaikeita elmnkokemuksia. Olennaista on se, miten nihin vaikeuksiin suhtaudutaan. Eheill on parhaat edellytykset ksitell elmn haasteita. Voidaan kuitenkin todeta, ett kaikki thn tutkimukseen osallistuneet olivat selviytyji.
