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1.
Electrifying the Canon: The Impact of Computing on Classical Studies   总被引:1,自引:0,他引:1  
The article offers a case study of the relationshipbetween current developments in Classical Studies andthe impact of computing and IT. The first sectionsummarises the main features of the Classical Studiesenvironment, especially the deep seated changes whichhave been taking place. These changes are then relatedto specific initiatives in Research, Teaching andLearning. The discussion is framed by a statement ofmicro-criteria for the evaluation of new developmentsand by reference to the macro-climate of debate aboutthe nature of cyberspace, especially the dichotomybetween conceptions of post-modern diversity and ofEnlightenment images of rational structures. It issuggested that these debates mirror those with whichthe discipline itself engages.  相似文献   
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There have been increases in the number of organic dairy farms in the UK in recent years. However, there is little information on the impact of organic regulations on cow welfare. As part of a larger study, we aimed to investigate differences between organic and non-organic farms in management practices and winter housing quality. Forty organic and 40 non-organic farms throughout the UK were visited. Organic and non-organic farms were paired for housing type, and as far as possible for herd size, genetic merit and location. A detailed questionnaire covering key aspects of dairy management was carried out with each farmer. On a subset of twenty pairs, an assessment of the quality of the winter housing for both lactating and dry cows was undertaken, covering the parlour, bedding, loafing and feeding areas. Management practices and building conditions varied greatly within farm types and there was considerable overlap between organic and non-organic farms. Milk yield, level and composition of concentrate feed, management of heifers and calving, and use of 'alternative treatments' to prevent and treat mastitis differed between organic and non-organic farms. In all other respects there were no differences between farm types. Building dimensions per cow did not differ, even though organic recommendations advise greater space per cow than recommended for non-organic farms. The similarity between organic and non-organic farms in most respects indicates that cow housing and health, based on both the described management regimes and the farmers' perceptions of disease incidence, on organic dairy farms is neither compromised by the regulations, nor considerably better than on non-organic farms.  相似文献   
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Online social networks (OSNs) offer people the opportunity to join communities where they share a common interest or objective. This kind of community is useful for studying the human behavior, diffusion of information, and dynamics of groups. As the members of a community are always changing, an efficient solution is needed to query information in real time. This paper introduces the Follow Model to present the basic relationship between users in OSNs, and combines it with the MapReduce solution to develop new algorithms with parallel paradigms for querying. Two models for reverse relation and high-order relation of the users were implemented in the Hadoop system. Based on 75 GB message data and 26 GB relation network data from Twitter, a case study was realized using two dynamic discussion communities:#musicmonday and #beatcancer. The querying performance demonstrates that the new solution with the implementation in Hadoop significantly improves the ability to find useful information from OSNs.  相似文献   
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Molybdenum dithiolene complexes with the general formula [MoTp*(NO)(L)], where Tp* = tris(3,5-dimethylpyrazolyl)hydroborate and L = toluene-3,4-dithiolate (L1), 1,2-benzenedithiolate (L2), or 3,6-dichloro-1,2-benzenedithiolate (L3), were found to exhibit the chemical and physical properties required for a photosensitiser in a photoelectrochemical cell. These complexes were characterised using micro-elemental, spectroscopic (IR and UV–vis) and electrochemical analyses. Cyclic voltammetry (CV) was used to determine the oxidation/reduction potentials and to calculate the energy band gap. All of the complexes had an energy band gap in the range 1.45–1.48 eV, which extends far into the visible light region. A TiO2 thin film to be used as a photoanode for photoelectrochemical cells was prepared using the paste technique on a Fluorine-doped Tin Oxide (FTO) plate and characterised using scanning electron microscope (SEM) and X-ray diffractometer (XRD). The [MoTp*(NO)(L)]-doped TiO2 photoanodes were analysed photochemically in a 1.0 M NaOH electrolyte solution using SCE reference and platinum counterelectrodes. The [MoTp*(NO)(L3)]-doped TiO2 photoanode exhibited an increased photoinduced current compared with the undoped TiO2 photoanode. The Cl atoms on the dithiolene group offered a better interaction between the photosensitiser molecule and the TiO2 photocatalyst by providing a means for halogen atom-induced chemical bonding. Based on the band edge calculations and the subsequent photocurrent results, these complexes may be potential photosensitisers for use in the preparation of photoelectrodes for photoelectrochemical cells.  相似文献   
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The analysis of almost 200 Scottish Sphagnum moss samples collected over the past 170 years has revealed trends in the isotopic composition of lead similar to those previously established for dated Scottish lake sediments and peat bogs, lending credibility to these proxy records of atmospheric lead contamination and deposition. The effect of temporal variations in contributions from sources such as smelting of indigenous lead ores (206Pb/207Pb approximately 1.16-1.18), coal combustion (206Pb/207Pb approximately 1.17-1.19), and the use of imported Australian lead (206Pb/207Pb approximately 1.04) was clearly seen in the Scottish moss 206Pb/207Pb record. This showed some differences from the corresponding archival herbage record for the south of England, where the initial influence of Australian lead occurred earlier, at the end of the 19th century. A significant decline from a 206Pb/ 207Pb value of approximately 1.17 in the Scottish moss record began in the 1920s and continued until the 1980s (206Pb/207Pb approximately 1.12). The success of measures to reduce lead emissions to the atmosphere over the past 20 years in the U.K., in particular from petrol-engined vehicles using alkyl lead additives manufactured primarily from Australian lead, is evident in both the increasing 206Pb/207Pb ratio and falling lead concentration data for Scottish moss.  相似文献   
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Behavior of intact and damaged honeycombs: a finite element study   总被引:3,自引:0,他引:3  
The Young’s moduli, the elastic buckling strength and the plastic collapse strength of regular honeycombs with defects consisting of missing cells in the structure were analyzed using the finite element method. The behavior of intact honeycombs was first analyzed; the results of this numerical study are consistent with those of previous analyses. The effect of single, isolated defects of varying sizes and the effect of the separation distance between two defects on the elastic and plastic behaviors were then analyzed. Single, isolated defects reduce the modulus and strength. The elastic buckling strength of a honeycomb with a defect normalized by the intact strength decreases directly with the ratio of the minimum net cross-sectional area normalized by the intact cross-sectional area. The plastic collapse strength of a honeycomb with a defect normalized by the intact strength decreases less rapidly than the ratio of the minimum net cross-sectional area normalized by the intact cross-sectional area. Two closely spaced, separate defects interact to reduce the elastic buckling strength of a honeycomb; at a separation distance of about ten cells separate defects act independently. The separation distance between two defects has little effect on the Young’s modulus or the plastic collapse strength of a honeycomb. The finite element analysis allows localization behavior to be studied: we find that the localization strain decreases with increasing .  相似文献   
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Describes how the 2nd author's (see record 1975-02991-001) structural analysis of social behavior (SASB) offers a new approach to the old problem of how to measure the complex and elusive concepts that are critical to family theory and therapy. SASB includes a theoretical model and an assessment methodology that can be applied to disturbed family relationships and interaction patterns. It also provides operational definitions and measures of distressed family processes that have been linked to major psychopathology, such as double binds and pseudomutuality. The conceptual framework of SASB is compatible with family systems and psychodynamic theories, and it applies to a range of healthy and distressed family functioning. SASB's promise for family assessment is illustrated, and an overview of the SASB model and methods is presented. Several central concepts from selected theories of the schizophrenic's family are operationalized. (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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