967 resultados para Function theory
Resumo:
We applied small-angle neutron scattering (SANS) and ultra small-angle neutron scattering (USANS) to monitor evolution of the CO2 adsorption in porous silica as a function of CO2 pressure and temperature in pores of different sizes. The range of pressures (0 < P < 345 bar) and temperatures (T=18 OC, 35 OC and 60 OC) corresponded to subcritical, near critical and supercritical conditions of bulk fluid. We observed that the adsorption behavior of CO2 is fundamentally different in large and small pores with the sizes D > 100 Å and D < 30 Å, respectively. Scattering data from large pores indicate formation of a dense adsorbed film of CO2 on pore walls with the liquid-like density (ρCO2)ads≈0.8 g/cm3. The adsorbed film coexists with unadsorbed fluid in the inner pore volume. The density of unadsorbed fluid in large pores is temperature and pressure dependent: it is initially lower than (ρCO2)ads and gradually approaches it with pressure. In small pores compressed CO2 gas completely fills the pore volume. At the lowest pressures of the order of 10 bar and T=18 OC, the fluid density in smallest pores available in the matrix with D ~ 10 Å exceeds bulk fluid density by a factor of ~ 8. As pressure increases, progressively larger pores become filled with the condensed CO2. Fluid densification is only observed in pores with sizes less than ~ 25 – 30 Å. As the density of the invading fluid reaches (ρCO2)bulk~ 0.8 g/cm3, pores of all sizes become uniformly filled with CO2 and the confinement effects disappear. At higher densities the fluid in small pores appears to follow the equation of state of bulk CO2 although there is an indication that the fluid density in the inner volume of large pores may exceed the density of the adsorbed layer. The equivalent internal pressure (Pint) in the smallest pores exceeds the external pressure (Pext) by a factor of ~ 5 for both sub- and supercritical CO2. Pint gradually approaches Pext as D → 25 – 30 Å and is independent of temperature in the studied range of 18 OC ≤ T ≤ 60 OC. The obtained results demonstrate certain similarity as well as differences between adsorption of subcritical and supercritical CO2 in disordered porous silica. High pressure small angle scattering experiments open new opportunities for in situ studies of the fluid adsorption in porous media of interest to CO2 sequestration, energy storage, and heterogeneous catalysis.
Resumo:
In this chapter, we are going to consider how language and practice interact in the process of supporting the learning of students with diverse abilities. You will learn that it is necessary for teachers to understand that while labels carry an administrative function in schools, when used carelessly they operate to stigmatise and exclude those whom we are working to include. This chapter will introduce the concept of equity and explain how the dilemma of difference emerges when we try to determine who should receive support and how. The chapter will also explain how an appreciation of language can help to inform and transform our pedagogy. An example of inclusion in action is provided to illustrate how inclusive language in practice can promote deep cultural changes that benefit both students and teachers. The process of determining appropriate and effective education of students with additional support requirements is troubled by what some refer to as the ‘dilemma of difference’. This dilemma derives mainly from the nature of language and our need to use certain words, terms and categories in order to share common understandings. Without these, educators cannot hope to arrive on the same page, yet such words can take on a life of their own; influencing thoughts, perspectives and attitudes in ways that far outstrip original intentions. The drive for clarity, however, through definition and diagnostic classification can ultimately obscure because of the cultural meanings that become invested within these terms through their use over time and in different professional contexts. In effect, trying to define “difference” in order to provide the right support to particular students is a process that entrenches normative boundaries that in turn create, accentuate and stigmatise whatever we have decided constitutes difference. Language is thus a powerful and dangerous weapon but, like other weapons, language can both hurt and defend. Understanding the power of language enables educators to use it both wisely and safely to the maximum benefit of their students. This chapter will discuss how teachers can recognise and support their students in ways that avoid stigma and the closure of stereotyping.
Resumo:
The main purpose of this longitudinal study was to investigate the role of motivational climates, perceived competence and motivational regulations as antecedents of self-reported physical activity during junior high school years. The participants included 237 Finnish students (101 girls, 136 boys) that were 13 years old at the first stage of the study. Students completed the motivational climate and perceived competence questionnaires at Grade 7, motivation towards physical education questionnaire at Grade 8, and self-reported physical activity questionnaire at Grade 9. A path analysis revealed a path from task-involving motivational climate via perceived competence and intrinsic motivation to self-reported physical activity. Perceived competence and intrinsic motivation were statistically significant mediators between task-involving motivational climate and self-reported physical activity. This finding supports the four-stage causal sequence model of motivation.
Resumo:
The issue of carbon sequestration rights has become topical following the United Nations Convention on Climate Change (United Nations 1992 at page 1414) and the subsequent Kyoto Protocol (United Nations Climate Change Secretariat 1998) which identified emissions trading as one of the mechanisms to reduce greenhouse gas emissions. Australian states have responded by creating a legal framework for the recognition of rights to bio-sequestered carbon. There is a lack of uniformity in the approach of each state to the recognition of these rights, which vary from the creation of new and novel interests in land to the adoption of more traditional rights such as a profit a prendre. Rights to bio-sequestered carbon are likely to have an impact on the utility, marketability, value and financing of rural land holdings. Despite the creation of the legal framework for recognition of rights to sequestrated carbon, there has been a delay in the introduction of a formalised carbon trading scheme in Australia. In the absence of an established carbon market, this paper addresses the applicability of contingent valuation theory to assess the value of bio-sequestered carbon rights to a rural land holder. Limitations and potential controversies associated with this application of contingent valuation theory are also addressed in this paper.
Resumo:
Much has been written on Michel Foucault’s reluctance to clearly delineate a research method, particularly with respect to genealogy (Harwood 2000; Meadmore, Hatcher, & McWilliam 2000; Tamboukou 1999). Foucault (1994, p. 288) himself disliked prescription stating, “I take care not to dictate how things should be” and wrote provocatively to disrupt equilibrium and certainty, so that “all those who speak for others or to others” no longer know what to do. It is doubtful, however, that Foucault ever intended for researchers to be stricken by that malaise to the point of being unwilling to make an intellectual commitment to methodological possibilities. Taking criticism of “Foucauldian” discourse analysis as a convenient point of departure to discuss the objectives of poststructural analyses of language, this paper develops what might be called a discursive analytic; a methodological plan to approach the analysis of discourses through the location of statements that function with constitutive effects.
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This study investigates the citation patterns of theoretical and empirical papers published in a top economics journal, namely American Economic Review, over a period of almost 30 years, while also exploring the determinants of citation success. The results indicate that empirical papers attract more citation success than theoretical studies. However, the pattern over time is very similar. Moreover, among empirical papers it appears that the cross-country studies are more successful than single country studies focusing on North America data or other regions.
Resumo:
This paper examines the role of first aid training in increasing adolescent helping behaviours when taught in a school-based injury prevention program, Skills for Preventing Injury in Youth (SPIY). The research involved the development and application of an extended Theory of Planned Behaviour (TPB), including “behavioural willingness in a fight situation,” “first aid knowledge” and “perceptions of injury seriousness”, to predict the relationship between participation in SPIY and helping behaviours when a friend is injured in a fight. From 35 Queensland high schools, 2500 Year 9 students (mean age = 13.5, 40% male) completed surveys measuring their attitudes, perceived behavioural control, subjective norms and behavioural intention, from the TPB, and added measures of behavioural willingness in a fight situation, perceptions of injury seriousness and first aid knowledge, to predict helping behaviours when a friend is injured in a fight. It is expected that the TPB will significantly contribute to understanding the relationship between participation in SPIY and helping behaviours when a friend is injured in a fight. Further analyses will determine whether the extension of the model significantly increases the variance explained in helping behaviours. The findings of this research will provide insight into the critical factors that may increase adolescent bystanders’ actions in injury situations.
Resumo:
The main aim of this paper is to describe an adaptive re-planning algorithm based on a RRT and Game Theory to produce an efficient collision free obstacle adaptive Mission Path Planner for Search and Rescue (SAR) missions. This will provide UAV autopilots and flight computers with the capability to autonomously avoid static obstacles and No Fly Zones (NFZs) through dynamic adaptive path replanning. The methods and algorithms produce optimal collision free paths and can be integrated on a decision aid tool and UAV autopilots.
Resumo:
Deep inelastic neutron scattering measurements on liquid 3He-4He mixtures in the normal phase have been performed on the VESUVIO spectrometer at the ISIS pulsed neutron source at exchanged wave vectors of about q≃120.0Å-1. The neutron Compton profiles J(y) of the mixtures were measured along the T=1.96K isotherm for 3He concentrations, x, ranging from 0.1 to 1.0 at saturated vapor pressures. Values of kinetic energies 〈T〉 of 3He and 4He atoms as a function of x, 〈T〉(x), were extracted from the second moment of J(y). The present determinations of 〈T〉(x) confirm previous experimental findings for both isotopes and, in the case of 3He, a substantial disagreement with theory is found. In particular 〈T〉(x) for the 3He atoms is found to be independent of concentration yielding a value 〈T〉3(x=0.1)≃12K, much lower than the value suggested by the most recent theoretical estimates of approximately 19 K.
Resumo:
The paper examines the impact of the introduction of no-fault divorce legislation in Australia. The approach used is rather novel, a hazard model of the divorce rate is estimated with the role of legislation captured via a time-varying covariate. The paper concludes that contrary to US empirical evidence, no-fault divorce legislation appears to have had a positive impact upon the divorce rate in Australia.
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The book examines the correlation between Intellectual Property Law – notably copyright – on the one hand and social and economic development on the other. The main focus of the initial overview is on historical, legal, economic and cultural aspects. Building on that, the work subsequently investigates how intellectual property systems have to be designed in order to foster social and economic growth in developing countries and puts forward theoretical and practical solutions that should be considered and implemented by policy makers, legal experts and the Word Intellectual Property Organization (WIPO).
Resumo:
The Theory of the Growth of The Firm by Edith Penrose, first published in 1959, is a seminal contribution to the field of management. Penrose's intention was to create a theory of firm growth which was logically consistent and empirically tractable (Buckley and Casson, 2007). Much attention, however, has been focused on her unintended contribution to the resource-based view (henceforth RBV) (e.g. Kor and Mahoney, 2004; Lockett and Thompson, 2004) rather than her firm growth theory. We feel that this is unfortunate because despite a rapidly growing body of empirical work, conceptual advancement in growth studies has been limited (Davidsson and Wiklund, 2000; Davidsson et ai., 2006; Delmar, 1997; Storey, 1994). The growth literature frequently references Penrose's work, but little explicit testing of her ideas has been undertaken. This is surprising given that Penrose's work remains the most comprehensive theory of growth to date. One explanation is that she did not formality present her arguments, favouring verbal exposition over formalized models (Lockett, 2005; Lockett and Thompson, 2004). However, the central propositions and conclusions of her theory can be operationalized and empirically tested.
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A value-shift began to influence global political thinking in the late 20th century, characterised by recognition of the need for environmentally, socially and culturally sustainable resource development. This shift entailed a move away from thinking of ‘nature’ and ‘culture’ as separate entities – the former existing to serve the latter – toward the possibility of embracing the intrinsic worth of the nonhuman world. Cultural landscape theory recognises ‘nature’ as at once both ‘natural’, and a ‘cultural’ construct. As such, it may offer a framework through which to progress in the quest for ‘sustainable development’. This study makes a contribution to this quest by asking whether contemporary developments in cultural landscape theory can contribute to rehabilitation strategies for Australian open-cut coal mining landscapes. The answer is ‘yes’. To answer the research question, a flexible, ‘emergent’ methodological approach has been used, resulting in the following outcomes. A thematic historical overview of landscape values and resource development in Australia post-1788, and a review of cultural landscape theory literature, contribute to the formation of a new theoretical framework: Reconnecting the Interrupted Landscape. This framework establishes a positive answer to the research question. It also suggests a method of application within the Australian open-cut coal mining landscape, a highly visible exemplar of the resource development landscape. This method is speculatively tested against the rehabilitation strategy of an operating open-cut coal mine, concluding with positive recommendations to the industry, and to government.
Resumo:
Research into hyperinsulinemic laminitis has progressed significantly in recent years with the use of the prolonged-euglycemic, hyperinsulinemic clamp (p-EHC). Previous investigations of laminitis pathophysiology have focused on digital vascular dysfunction, inflammation, altered glucose metabolism within the lamellae, and lamellar basement membrane breakdown by metalloproteinases. The etiopathogenesis of laminitis occurring in association with hyperinsulinemia is yet to be fully characterized, but it may not involve these mechanisms. Insulin stimulates cellular proliferation and can also affect other body systems, such as the insulin-like growth factor (IGF) system. Insulin-like growth factor-1 (IGF-1) is structurally homologous to insulin and, like insulin, binds with strong affinity to a specific tyrosine kinase receptor on the cell surface to produce its effects, which include promoting cell proliferation. Receptors for IGF-1 (IGF-1R) are present in the lamellar epidermis. An alternative theory for the pathogenesis of hyperinsulinemic laminitis is that uncontrolled cell proliferation, mediated through both the insulin receptor (InsR) and IGF-1R, leads to lengthening, weakening, and failure of the lamellae. An analysis of the proliferative activity of lamellar epidermal cells during the developmental and acute phases of hyperinsulinemic laminitis, and lamellar gene expression of the InsR and IGF-1R was undertaken.