982 resultados para sociocultural theory
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The book presents a reconstruction, interpretation and critical evaluation of the Schumpeterian theoretical approach to socio-economic change. The analysis focuses on the problem of social evolution, on the interpretation of the innovation process and business cycles and, finally, on Schumpeter s optimistic neglect of ecological-environmental conditions as possible factors influencing social-economic change. The author investigates how the Schumpeterian approach describes the process of social and economic evolution, and how the logic of transformations is described, explained and understood in the Schumpeterian theory. The material of the study includes Schumpeter s works written after 1925, a related part of the commentary literature on these works, and a selected part of the related literature on the innovation process, technological transformations and the problem of long waves. Concerning the period after 1925, the Schumpeterian oeuvre is conceived and analysed as a more or less homogenous corpus of texts. The book is divided into 9 chapters. Chapters 1-2 describe the research problems and methods. Chapter 3 is an effort to provide a systematic reconstruction of Schumpeter's ideas concerning social and economic evolution. Chapters 4 and 5 focus their analysis on the innovation process. In Chapters 6 and 7 Schumpeter's theory of business cycles is examined. Chapter 8 evaluates Schumpeter's views concerning his relative neglect of ecological-environmental conditions as possible factors influencing social-economic change. Finally, chapter 9 draws the main conclusions.
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This thesis consists of an introduction, four research articles and an appendix. The thesis studies relations between two different approaches to continuum limit of models of two dimensional statistical mechanics at criticality. The approach of conformal field theory (CFT) could be thought of as the algebraic classification of some basic objects in these models. It has been succesfully used by physicists since 1980's. The other approach, Schramm-Loewner evolutions (SLEs), is a recently introduced set of mathematical methods to study random curves or interfaces occurring in the continuum limit of the models. The first and second included articles argue on basis of statistical mechanics what would be a plausible relation between SLEs and conformal field theory. The first article studies multiple SLEs, several random curves simultaneously in a domain. The proposed definition is compatible with a natural commutation requirement suggested by Dubédat. The curves of multiple SLE may form different topological configurations, ``pure geometries''. We conjecture a relation between the topological configurations and CFT concepts of conformal blocks and operator product expansions. Example applications of multiple SLEs include crossing probabilities for percolation and Ising model. The second article studies SLE variants that represent models with boundary conditions implemented by primary fields. The most well known of these, SLE(kappa, rho), is shown to be simple in terms of the Coulomb gas formalism of CFT. In the third article the space of local martingales for variants of SLE is shown to carry a representation of Virasoro algebra. Finding this structure is guided by the relation of SLEs and CFTs in general, but the result is established in a straightforward fashion. This article, too, emphasizes multiple SLEs and proposes a possible way of treating pure geometries in terms of Coulomb gas. The fourth article states results of applications of the Virasoro structure to the open questions of SLE reversibility and duality. Proofs of the stated results are provided in the appendix. The objective is an indirect computation of certain polynomial expected values. Provided that these expected values exist, in generic cases they are shown to possess the desired properties, thus giving support for both reversibility and duality.
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Apart from their intrinsic physical interest, spin-polarized many-body effects are expected to be important to the working of spintronic devices. A vast literature exists on the effects of a spin-unpolarized electron-hole plasma on the optical properties of a semiconductor. Here, we include the spin degree of freedom to model optical absorption of circularly polarized light by spin-polarized bulk GaAs. Our model is easy to implement and does not require elaborate numerics, since it is based on the closed-form analytical pair-equation formula that is valid in 3d. The efficacy of our approach is demonstrated by a comparison with recent experimental data.
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Within the Grassmannian U(2N)/U(N) x U(N) nonlinear sigma-model representation of localization, one can study the low-energy dynamics of both a free and interacting electron gas. We study the crossover between these two fundamentally different physical problems. We show how the topological arguments for the exact quantization of the Hall conductance are extended to include the Coulomb interaction problem. We discuss dynamical scaling and make contact with the theory of variable range hopping. (C) 2005 Pleiades Publishing, Inc.
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The surface of a soft elastic film becomes unstable and forms a self-organized undulating pattern because of adhesive interactions when it comes in contact proximity with a rigid surface. For a single film, the pattern length scale lambda, which is governed by the minimization of the elastic stored energy, gives lambda similar to 3h, where h is the film thickness. Based on a linear stability analysis and simulations of adhesion and debonding, we consider the contact instability of an elastic bilayer, which provides greater flexibility in the morphological control of interfacial instability. Unlike the case of a single film, the morphology of the contact instability patterns, debonding distance, and debonding force in a bilayer can be controlled in a nonlinear way by varying the thicknesses and shear moduli of the films. Interestingly, the pattern wavelength in a bilayer can be greatly increased or decreased compared to a single film when the adhesive contact is formed by the stiffer or the softer of the two films, respectively. In particular, lambda as small as 0.5h can be obtained. This indicates a new strategy for pattern miniaturization in elastic contact lithography.
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A study has been made of the problem of steady, one-dimensional, laminar flame propagation in premixed gases, with the Lewis number differing from (and equal to) unity. Analytical solutions, using the method of matched asymptotic expansions, have been obtained for large activation energies. Numerical solutions have been obtained for a wide range of the reduced activation temperature parameter (n {geometrically equal to} E/RTb), and the Lewis number δ. The studies reveal that the flame speed eigenvalue is linear in Lewis number for first order and quadratic in Lewis number for second order reactions. For a quick determination of flame speeds, with reasonable accuracy, a simple rule, expressing the flame speed eigenvalue as a function of the Lewis number and the centroid of the reaction rate function, is proposed. Comparisons have been made with some of the earlier works, for both first and second order reactions.
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Tämän tutkielman aiheena on kulttuurienvälisyys kulttuurienvälisessä kaksikielisessä opetuksessa (Educación Intercultural Bilingüe, EIB) Boliviassa ja erityisesti kulttuurienvälisen kaksikielisen koulutuksen maisteriohjelmassa (Maestría en Educación Intercultural Bilingüe), jota koordinoi PROEIB Andes -järjestö yhteistyössä Cochabamban Universidad Mayor de San Simónin kanssa. Tutkielman tarkoituksena on selvittää, miten kulttuurienvälisyys määritellään ja mitä se käytännössä merkitsee opetuksen eri osa-alueilla: sisällöissä, opetusmetodeissa ja -materiaaleissa sekä arvioinnissa. Koska kulttuurienvälisen kaksikielisen opetuksen toteutus ja tutkiminen eri Latinalaisen Amerikan maissa on tähän asti painottunut lähes yksinomaan perusopetukseen, pyrin työssäni keskittymään kulttuurienvälisyyden ilmentymiin nimenomaan bolivialaisessa korkeakoulukontekstissa. Tutkielman aineistona on käytetty kahdeksaa EIB -asiantuntijoiden teemahaastattelua, jotka FM Eila Isotalus on tehnyt Boliviassa vuonna 2004. Haastatteluaineisto analysoitiin teoriasidonnaista eli abduktiivista sisällönanalyysiä käyttäen. Tutkielman teoriatausta koostuu yhtäältä kulttuurienvälisyyteen ja monikulttuurisuuteen liittyvien käsitteiden määrittelystä, ja toisaalta kulttuurienväliseen opetukseen liittyvien mallien esittelystä. Aineiston analyysissä avuksi on ollut etenkin James A. Banksin teoria monikulttuurisen opetuksen viidestä ulottuvuudesta, joiden kautta on voitu pohtia kulttuurienvälisyyden toteutumista opetuksen eri osa-alueilla ja nostaa esille bolivialaisen kulttuurienvälisen opetuksen erityispiirteitä. Aineiston analyysissä ilmenee, että kulttuurienvälisyyden käsitteen määrittely on vahvasti kontekstisidonnainen ja jatkuva prosessi, johon vaikuttavat eri toimijoiden näkemykset ja vaatimukset. EIB -asiantuntijoiden esittämät määrittelyt voidaan jakaa makro- ja mikrososiaaliseen kategoriaan sen mukaan, nähdäänkö kulttuurienvälisyys ensisijaisesti yhteiskunnallisena vai yksilötason käsitteenä. Aineistossa korostuu ajatus latinalaisamerikkalaisesta kulttuurienvälisyydestä poliittisena käsitteenä, jonka keskiössä on vaatimus yhteiskunnallisten valtasuhteiden muutoksesta. Yksi suurimmista haasteista kulttuurienvälisyyden toteuttamisessa bolivialaisessa korkeakouluopetuksessa ovat akateemiseen kulttuuriin liittyvät perinteet, jotka vaikeuttavat uusien toimintatapojen omaksumista. Kulttuurienvälisyys opetuksessa on toistaiseksi tarkoittanut etupäässä sisältöjen monipuolistamista lisäämällä opetusohjelmiin elementtejä paikallisista kulttuureista. Tärkeänä askeleena EIB:n kehityksessä voidaan pitää painopisteen siirtymistä sisältökysymyksistä kulttuurienvälisten opetusmetodien luomiseen. Näiden opetusmenetelmien tulisi pohjautua ymmärrykseen oppimisesta kokonaisvaltaisena, yhteisöllisenä prosessina ja siten kuroa umpeen kuilua koulun ja yhteisöjen arkielämän välillä. Opetusmenetelmien ja -materiaalien suhteen keskeinen kulttuurienvälisyyteen liittyvä kysymys on intiaanikansojen suullisen kulttuurin ja tiedon jakamisen perinteiden hyödyntäminen opetuksessa. Maisteriohjelman opiskelijoiden arvioinnissa pyritään huomioimaan yksilön kokonaisvaltainen kehitys pelkkien opintosuoritusten sijasta, mutta arvosanoihin pohjautuvasta arvostelukäytännöstä ei ole toistaiseksi voitu luopua yliopiston vaatimusten vuoksi. Kaiken kaikkiaan kulttuurienvälisyyden toteuttaminen EIB:ssä ja maisteriohjelmassa on pitkän tähtäimen prosessi, joka vaatii perinteisten opetuskäytäntöjen kyseenalaistamista ja korkeakouluopetuksessa myös akateemisen kulttuurin haastamista. On oleellisen tärkeää, että prosessiin osallistuvat asiantuntijoiden ohella myös esimerkiksi opiskelijat, intiaaniyhteisöt ja -järjestöaktiivit.
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A theory and generalized synthesis procedure is advocated for the design of weir notches and orifice-notches having a base in any given shape, to a depth a, such that the discharge through it is proportional to any singular monotonically-increasing function of the depth of flow measured above a certain datum. The problem is reduced to finding an exact solution of a Volterra integral equation in Abel form. The maximization of the depth of the datum below the crest of the notch is investigated. Proof is given that for a weir notch made out of one continuous curve, and for a flow proportional to the mth power of the head, it is impossible to bring the datum lower than (2m − 1)a below the crest of the notch. A new concept of an orifice-notch, having discontinuity in the curve and a division of flow into two distinct portions, is presented. The division of flow is shown to have a beneficial effect in reducing the datum below (2m − 1)a from the crest of the weir and still maintaining the proportionality of the flow. Experimental proof with one such orifice-notch is found to have a constant coefficient of discharge of 0.625. The importance of this analysis in the design of grit chambers is emphasized.
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It is shown that there is a strict one-to-one correspondence between results obtained by the use of "restricted" variational principles and those obtained by a moment method of the Mott-Smith type for shock structure.
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Agriculture’s contribution to climate change is controversial as it is a significant source of greenhouse gases but also a sink of carbon. Hence its economic and technological potential to mitigate climate change have been argued to be noteworthy. However, social profitability of emission mitigation is a result from factors among emission reductions such as surface water quality impact or profit from production. Consequently, to value comprehensive results of agricultural climate emission mitigation practices, these co-effects to environment and economics should be taken into account. The objective of this thesis was to develop an integrated economic and ecological model to analyse the social welfare of crop cultivation in Finland on distinctive cultivation technologies, conventional tillage and conservation tillage (no-till). Further, we ask whether it would be privately or socially profitable to allocate some of barley cultivation for alternative land use, such as green set-aside or afforestation, when production costs, GHG’s and water quality impacts are taken into account. In the theoretical framework we depict the optimal input use and land allocation choices in terms of environmental impacts and profit from production and derive the optimal tax and payment policies for climate and water quality friendly land allocation. The empirical application of the model uses Finnish data about production cost and profit structure and environmental impacts. According to our results, given emission mitigation practices are not self-evidently beneficial for farmers or society. On the contrary, in some cases alternative land allocation could even reduce social welfare, profiting conventional crop cultivation. This is the case regarding mineral soils such as clay and silt soils. On organic agricultural soils, climate mitigation practices, in this case afforestation and green fallow give more promising results, decreasing climate emissions and nutrient runoff to water systems. No-till technology does not seem to profit climate mitigation although it does decrease other environmental impacts. Nevertheless, the data behind climate emission mitigation practices impact to production and climate is limited and partly contradictory. More specific experiment studies on interaction of emission mitigation practices and environment would be needed. Further study would be important. Particularly area specific production and environmental factors and also food security and safety and socio-economic impacts should be taken into account.
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A density-functional approach on the hexagonal graphene lattice is developed using an exact numerical solution to the Hubbard model as the reference system. Both nearest-neighbour and up to third nearest-neighbour hoppings are considered and exchange-correlation potentials within the local density approximation are parameterized for both variants. The method is used to calculate the ground-state energy and density of graphene flakes and infinite graphene sheet. The results are found to agree with exact diagonalization for small systems, also if local impurities are present. In addition, correct ground-state spin is found in the case of large triangular and bowtie flakes out of the scope of exact diagonalization methods.
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A theoretical solution has been obtained for the state of stress in a rectangular plate under a pair of symmetrically placed rigid indenters. The stress distributions along the two central axes have been calculated for a square plate assuming the pressure distribution under the indenters as uniform, parabolic and one resulting from 'constant displacement' on a semiinfinite boundary, for different ratios of indenter-width to side of square. The results are compared with those of photoelastic analysis of Berenbaum and Brodie and the validity of the solution is discussed. The solution has been extended to orthotropic materials and numerical results for one type of coal are given.