975 resultados para similarity relations
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Since 2009, all Australian states require young people to be ‘earning or learning’ until age 17. Secondary schools and vocational colleges now accommodate students for whom the conventional academic pathways of the past were not designed. The paper reflects on a project designed to explore the moral orders in these institutional settings for managing such students in extended compulsory schooling. Originally designed as classroom ethnographies, the project involved observations over three to four weeks and interviews with teachers and students in five sites in towns experiencing high youth unemployment. The project aimed to support teachers to work productively in such classrooms with such students, under the assumption that teachers orchestrate classroom interactions. However, it became clear events in these classrooms were being shaped by relations and parties above and beyond the classroom, as much as by those present. Teachers and students were observed to both comply with, and push against, the layers of policy and institutional processes regulating their behaviours. This paper re-thinks the original project through the gaze and resources of institutional ethnography, to better account for the layers of accountabilities and documentation practices that impacted on both teacher and student behaviours. By tracing the extended webs of ‘ruling relations’, it shows both how teachers and students could make trouble for the institutional moral order, and then be held accountable for this trouble.
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Advances in neural network language models have demonstrated that these models can effectively learn representations of words meaning. In this paper, we explore a variation of neural language models that can learn on concepts taken from structured ontologies and extracted from free-text, rather than directly from terms in free-text. This model is employed for the task of measuring semantic similarity between medical concepts, a task that is central to a number of techniques in medical informatics and information retrieval. The model is built with two medical corpora (journal abstracts and patient records) and empirically validated on two ground-truth datasets of human-judged concept pairs assessed by medical professionals. Empirically, our approach correlates closely with expert human assessors ($\approx$ 0.9) and outperforms a number of state-of-the-art benchmarks for medical semantic similarity. The demonstrated superiority of this model for providing an effective semantic similarity measure is promising in that this may translate into effectiveness gains for techniques in medical information retrieval and medical informatics (e.g., query expansion and literature-based discovery).
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Introduction A pedagogical relationship - the relationship produced through teaching and learning - is, according to phenomenologist Max van Maanen, ‘the most profound relationship an adult can have with a child’ (van Maanen 1982). But what does it mean for a teacher to have a ‘profound’ relationship with a student in digital times? What, indeed, is an optimal pedagogical relationship at a time when the exponential proliferation and transformation of information across the globe is making for unprecedented social and cultural change? Does it involve both parties in a Facebook friendship? Being snappy with Snapchat? Tumbling around on Tumblr? There is now ample evidence of a growing trend to displace face-to-face interaction by virtual connections. One effect of these technologically mediated relationships is that a growing number of young people experience relationships as ‘mile-wide, inch-deep’ phenomena. It is timely, in this context, to explore how pedagogical relationships are being transmuted by Big Data, and to ask about the implications this has for current and future generations of professional educators.
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Purpose The purpose of this paper is to explore what the attitudes of small firm owner-managers are to developing the skills of their key resources and then examine how these and other factors affect owner-managers’ preferences for training these employees. Design/methodology/approach This study of training in small road transport firms in West Australia is cast in light of the literature on human resource management in small firms underpinned by insights drawn using the resource based view of the firm. Small firms (less than 20 people) dominate this industry, while the increasing freight task, and extreme distances between West Australian ports, towns and mines highlight this sectors’ importance. Survey results from 39 small road transport firms and interviews with nine owner-managers are analysed. Findings Legislative, regulatory and licensing requirements were shown to be a key determinant of skills development. Employers ensured that basic standards for employee certification and qualification were met, as the penalty for not doing so would be too high. Regulations drove the need for certain types of training – licenses, fatigue management, occupational health and safety, handling dangerous goods, the Maritime Security Identification Card card, forklift license, mine site inductions – while owner-managers knew where to get the training their staff needed. Although regulation appeared most visible in prescribing what happened in relation to training for drivers, the relevance of owner-managers’ attitudes could not be ignored, nor could conditions in the firms external environment as this shaped how these requirements were met. Research limitations/implications The RBV is useful in showing how skill development enabled similarity in skills across firms, while the attitudes owner-managers and economic and social conditions meant what happened in firms around skill development varied. The importance of small firm owner-managers’ attitudes are clearly highlighted and shown to influence organizational decisions and choices around training, but these were not independent of the regulatory framework and the economic and social conditions within which the firm operated. The small firms in this study did engage workers in formal training when necessary but it was put in the context of the idiosyncratic approach of the owner-manager and the day-to-day needs of the firm. “Training” was essentially about ensuring certain types of skills were held by employees and then passing on knowledge to ensure the behavior of employees was consistent with the owner-manager’s vision for the firm in its current environment. Originality/value Ways industry and government can encourage training activity that goes beyond the day-to-day firm needs are suggested.
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Studies of semantic context effects in spoken word production have typically distinguished between categorical (or taxonomic) and associative relations. However, associates tend to confound semantic features or morphological representations, such as whole-part relations and compounds (e.g., BOAT-anchor, BEE-hive). Using a picture-word interference paradigm and functional magnetic resonance imaging (fMRI), we manipulated categorical (COW-rat) and thematic (COW-pasture) TARGET-distractor relations in a balanced design, finding interference and facilitation effects on naming latencies, respectively, as well as differential patterns of brain activation compared with an unrelated distractor condition. While both types of distractor relation activated the middle portion of the left middle temporal gyrus (MTG) consistent with retrieval of conceptual or lexical representations, categorical relations involved additional activation of posterior left MTG, consistent with retrieval of a lexical cohort. Thematic relations involved additional activation of the left angular gyrus. These results converge with recent lesion evidence implicating the left inferior parietal lobe in processing thematic relations and may indicate a potential role for this region during spoken word production.
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Objects presented in categorically related contexts are typically named slower than objects presented in unrelated contexts, a phenomenon termed semantic interference. However, not all semantic relationships induce interference. In the present study, we investigated the influence of object part-relations in the blocked cyclic naming paradigm. In Experiment 1 we established that an object's parts do induce a semantic interference effect when named in context compared to unrelated parts (e.g., leaf, root, nut, bark; for tree). In Experiment 2) we replicated the effect during perfusion functional magnetic resonance imaging (fMRI) to identify the cerebral regions involved. The interference effect was associated with significant perfusion signal increases in the hippocampal formation and decreases in the dorsolateral prefrontal cortex. We failed to observe significant perfusion signal changes in the left lateral temporal lobe, a region that shows reliable activity for interference effects induced by categorical relations in the same paradigm and is proposed to mediate lexical-semantic processing. We interpret these results as supporting recent explanations of semantic interference in blocked cyclic naming that implicate working memory mechanisms. However, given the failure to observe significant perfusion signal changes in the left temporal lobe, the results provide only partial support for accounts that assume semantic interference in this paradigm arises solely due to lexical-level processes.
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Contemporary models of spoken word production assume conceptual feature sharing determines the speed with which objects are named in categorically-related contexts. However, statistical models of concept representation have also identified a role for feature distinctiveness, i.e., features that identify a single concept and serve to distinguish it quickly from other similar concepts. In three experiments we investigated whether distinctive features might explain reports of counter-intuitive semantic facilitation effects in the picture word interference (PWI) paradigm. In Experiment 1, categorically-related distractors matched in terms of semantic similarity ratings (e.g., zebra and pony) and manipulated with respect to feature distinctiveness (e.g., a zebra has stripes unlike other equine species) elicited interference effects of comparable magnitude. Experiments 2 and 3 investigated the role of feature distinctiveness with respect to reports of facilitated naming with part-whole distractor-target relations (e.g., a hump is a distinguishing part of a CAMEL, whereas knee is not, vs. an unrelated part such as plug). Related part distractors did not influence target picture naming latencies significantly when the part denoted by the related distractor was not visible in the target picture (whether distinctive or not; Experiment 2). When the part denoted by the related distractor was visible in the target picture, non-distinctive part distractors slowed target naming significantly at SOA of -150 ms (Experiment 3). Thus, our results show that semantic interference does occur for part-whole distractor-target relations in PWI, but only when distractors denote features shared with the target and other category exemplars. We discuss the implications of these results for some recently developed, novel accounts of lexical access in spoken word production.
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Automated digital recordings are useful for large-scale temporal and spatial environmental monitoring. An important research effort has been the automated classification of calling bird species. In this paper we examine a related task, retrieval of birdcalls from a database of audio recordings, similar to a user supplied query call. Such a retrieval task can sometimes be more useful than an automated classifier. We compare three approaches to similarity-based birdcall retrieval using spectral ridge features and two kinds of gradient features, structure tensor and the histogram of oriented gradients. The retrieval accuracy of our spectral ridge method is 94% compared to 82% for the structure tensor method and 90% for the histogram of gradients method. Additionally, this approach potentially offers a more compact representation and is more computationally efficient.
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Investigations on the phase relations and dielectric properties of (1 -x)BaTiO3 + xNd2/3TiO 3 (BNT) ceramics sintered in air below 1650 K have been carried out. X-ray powder diffraction studies indicate apparent phase singularity for compositions with x < 0.3. Nd2Ti207 is detected at higher neodymium concentrations. The unit cell parameter changes continuously with neodymium content, and BaTiO3 is completely cubic at room temperature with x -- 0.0525, whereas electron diffraction studies indicate that the air-sintered BNT ceramics with x > 0.08 contain additional phases that are partly amorphous even to an electron beam. SEM observations reveal that BaTiO3 grains are mostly covered by a molten intergranular phase, and show the presence of randomly distributed Nd2Ti207 grains. Energy dispersive X-ray analysis shows the Ba-Nd-Ti ternary composition of the intergranular phase. Differential thermal analysis studies support the formation of a partial melt involving dissolution-precipitation of boundary layers of BaTiO3 grains. These complex phase relations are accounted for in terms of the phase instability of BaTiO3 with large cation-vacancy concentration as a result of heavy Nd 3+ substitution. The absence of structural intergrowth in (1 - x)BaTiO3 + xNd2/3TiO3 under oxidative conditions leads to a separation of phases wherein the new phases undergo melting and remain X-ray amorphous. BNT ceramics with 0.1 < x < 0.3 have ~eff >~ 104 with tan 6 < 0.1 and nearly flat temperature capacitance characteristics. The grain-size dependence of ee,, variations of ~eff and tan 6 with the measuring frequency, the non-ohmic resistivities, and the non-linear leakage currents at higher field-strengths which are accompanied by the decrease in eeff and rise in tan 3, are explained on the basis of an intergranular (internal boundary layer) dielectric characteristic of these ceramics.
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The structure of time dependent jets in rotating fluids using similarity transformations is studied theoretically for which exact solutions are discussed. Approximate solution using a modified yon Mises transformation is also explored.
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In previous experiments, increased leaf-Phosphorus (P) content with increasing P supply enhanced the individual leaf expansion and water content of fresh cotton leaves in a severely drying soil. In this paper, we report on the bulk water content of leaves and its components, free and bound water, along with other measures of plant water status, in expanding cotton leaves of various ages in a drying soil with different P concentrations. The bound water in living tissue is more likely to play a major role in tolerance to abiotic stresses by maintaining the structural integrity and/or cell wall extensibility of the leaves, whilst an increased amount of free water might be able to enhance solute accumulation, leading to better osmotic adjustment and tolerance to water stress, and maintenance of the volumes of sub-cellular compartments for expansive leaf growth. There were strong correlations between leaf-P%, leaf water (total, free and bound water) and leaf expansion rate (LER) under water stress conditions in a severely drying soil. Increased soil-P enhanced the uptake of P from a drying soil, leading to increased supply of osmotically active inorganic solutes to the cells in growing leaves. This appears to have led to the accumulation of free water and more bound water, ultimately leading to increased leaf expansion rates as compared to plants in low P soil under similar water stress conditions. The greater amount of bound and free water in the high-P plants was not necessarily associated with changes in cell turgor, and appears to have maintained the cell-wall properties and extensibility under water stressed conditions in soils that are nutritionally P-deficient.
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Phase relations in the system Ta-Rh-O were determined by analysis of quenched samples corresponding to thirteen compositions inside the ternary triangle after equilibration at 1273 K. All the Ta-Rh alloys were found to be in equilibrium with Ta2O5. Only one ternary oxide TaRhO4 was detected. Based on phase relations in the ternary system, a solid-state electrochemical cell, incorporating calcia-stabilized zirconia as the electrolyte, was designed to measure the standard Gibbs energy of formation (Delta G degrees, J mol(-1)) of TaRhO4 in the temperature range from 900 to 1300 K. For the reaction, 1/2 beta-Ta2O5 + 1/2 Rh2O3(ortho) -> TaRhO4 Delta G degrees = -42993 + 5.676T (+/- 85) The calculated decomposition temperatures of TaRhO4 are 1644 +/- 5K in pure O-2 and 1543 +/- 5K in air at a total pressure p(o) = 0.1 MPa. Thermodynamic properties of TaRhO4 at 298.15K have been evaluated from the results. The limited experimental thermodynamic data for Rh-rich alloys available in the literature are in fair accord with Miedema's model. The Gibbs energies of formation of the different phases in the binary system Ta-Rh were estimated based on these inputs, consistent with the binary phase diagram. Based on the thermodynamic information on the stability of various phases, an oxygen potential diagram for the system Ta-Rh-O at 1273K was constructed. Also presented are temperature-composition diagrams for the ternary system at constant oxygen partial pressures (po(2)/p(o) = 0.212 and 10(-6)) calculated form the basic data.