601 research outputs found

    Henry Odera Oruka, Ecophilosophy and Climate Change

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    The purpose of this paper is to explore what Henry Odera Oruka, a renowned ecophilosopher and Director designate of an Ecophilosophy Centre, would have thought and argued in the sphere of climate change if he had remained alive beyond 1995 and up to the present time. The methodology of the paper combines an analytic and normative study of ethical issues concerning climate change that arose during the 1990s or have arisen during the subsequent period, with a critical examination of relevant international conferences of the period 1995 to 2012, and of intervening developments, together with inferences grounded in Odera’s knowledge, experience and interests to conclusions about attitudes, arguments and stances that he would have been likely to form in the course of that same period. The central argument of the paper is premised on key concerns of Odera, not least his concern for a “future beyond poverty” for Africa (the title of the World Futures Studies Federation Conference that he organised in Nairobi in 1995), and for characteristic African values. It is also premised on the impression likely to have been made on Odera by the remarks of Michel van Hulten at this Conference. It argues accordingly that Odera would have been likely to defend some version of the Contraction and Convergence strategy, modified to take account of recent discoveries about humanity’s carbon budget, and the extent to which much of this budget has already been consumed in the period since 1990 by the industrialised countries, to the detriment of developing countries such as the countries of Africa. This paper is relevant to Thought and Practice through presenting to scholars with broad interests in the humanities and social sciences an original examination of climate change ethics and its bearing on Africa, and of Odera’s likely attitudes, arguments and stances in this field, thus supplying suggestions about further research needing to be undertaken on these intellectual, social and political issues, with their special and vital importance for contemporary Africa. Key Words Henry Odera Oruka, ecophilosophy, climate change ethics, impacts of climate change on Africa, Contraction and Convergence, humanity’s carbon budget

    Electronic resource discovery systems: from user behaviour to design.

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    Information seeking is a central part of academic development for both students and researchers. However, this is often hindered by complex and highly complicated electronic resource discovery systems. One approach to improving these resources is to understand the difficulties and likely causes of problems when using current systems and how people develop their searching, retrieval and storage strategies. These might provide useful information about the requirements for future design. In this paper we present our findings from UBiRD, a project investigating user search behaviour in electronic resource discovery systems based on a qualitative study of 34 users from three UK universities. We then describe how the information gathered during the study helped inform the design of INVISQUE, a novel non-conventional interface for searching and querying on-line scholarly information. In addition, the theories and design principles used during the INVISQUE design are discussed

    Intrahousehold Resource Allocation in Rural Pakistan: A Semi-parametric Analysis

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    We estimate semiparametric Engel curves for rural Pakistan using a large household survey. This allows us to obtain consistent estimates of the effects of household size and composition on consumption patterns even when these demographic variables are correlated with an unknown function of income. The coefficients on the household composition variables are used to infer patterns of intrahousehold allocation. While there is little evidence of gender bias amongst children, adult males appear to get more than adult females. There is a tendency amongst males for workers to get more than dependents. There is no evidence of differential treatment of the elderly and higher birth-order children. We identify substantial economies of size in food consumption. We also find that Engel curces for food, adult goods and child goods are nonlinear, which suggests that the PIGLOG class of demand models in inappropriate.Semiparametric estimation, intrahousehold resource allocation, gender bias, Engel curves.

    A provenance task abstraction framework

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    Visual analytics tools integrate provenance recording to externalize analytic processes or user insights. Provenance can be captured on varying levels of detail, and in turn activities can be characterized from different granularities. However, current approaches do not support inferring activities that can only be characterized across multiple levels of provenance. We propose a task abstraction framework that consists of a three stage approach, composed of (1) initializing a provenance task hierarchy, (2) parsing the provenance hierarchy by using an abstraction mapping mechanism, and (3) leveraging the task hierarchy in an analytical tool. Furthermore, we identify implications to accommodate iterative refinement, context, variability, and uncertainty during all stages of the framework. A use case describes exemplifies our abstraction framework, demonstrating how context can influence the provenance hierarchy to support analysis. The paper concludes with an agenda, raising and discussing challenges that need to be considered for successfully implementing such a framework

    Charge order at the frontier between the molecular and solid states in Ba3NaRu2O9

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    We show that the valence electrons of Ba3NaRu2O9, which has a quasi-molecular structure, completely crystallize below 210 K. Using an extended Hubbard model, we show that the charge ordering instability results from long-range Coulomb interactions. However, orbital ordering, metal-metal bonding and formation of a partial spin gap enforce the magnitude of the charge separation. The striped charge order and frustrated hcp lattice of Ru2O9 dimers lead to competition with a quasi-degenerate charge-melted phase under photo-excitation at low temperature. Our results establish a broad class of simple metal oxides as models for emergent phenomena at the border between the molecular and solid states.Comment: Minor changes, with supporting information. To appear in Phys. Rev. Let

    Study of Magnetic Properties of A_2B^'NbO_6 (A=Ba,Sr, (BaSr): and B^'=Fe and Mn) double perovskites

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    We have studied the magnetic properties of Ba_2FeNbO_6 and Ba_2MnNbO_6. it is seen that Ba_2FeNbO_6 is an antiferromagnet with a weak ferromagnetic behaviour at 5K while Ba_2MnNbO_6 shows two magnetic transitions one at 45 K and the other at 12K. Electron spin resonance (ESR) measurements at room temperature show that the Mn compound does not show any Jahn-Teller distortion. It is also seen that the Neel temperature of the A_2FeNbO_6 (A=Ba,Sr, BaSr) compounds do not vary significantly. However variations in the average A-site ionic radius influence the formation of short range correlations that persist above T_N.Comment: 10 oages, 5 figures, MMM, to appear in J.Appl.Phy

    Substitution effect of Zn and Cu in MgB2 on Tc and structure

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    The investigation of Zn substitution in MgB2 polycrystalline samples shows that about 0.1 Zn can be substituted in the structure of Mg deficient samples while it can not be substituted in stoichiometric MgB2. As a result of the isovalent Zn substitution into the Mg position of Mg deficient samples the a and c lattice constants increase by about 0.17% and 0.2% respectively. Susceptibility measurements show a slight lowering of Tc by about 0.5 K for 0.05 Zn, which decreases to 0.2 K for 0.1 Zn substitution. Investigation of the pressure derivative of Tc shows dp/dTc = -0.15 K/kbar independent of Zn content. Substitution of Cu leads to multiphase samples without any changes of lattice constants, which indicates that Cu does not enter the structure of MgB2. The Cu substitution broadens the superconducting transition considerably, while the onset remains unchanged.Comment: 13 pages, 5 figure
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