10,702 research outputs found

    Pluto and the Platypus: An Odd Ball and an Odd Duck — On Classificatory Norms

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    Some astronomers believe that we have discovered that Pluto is not a planet. I contest this assessment. Recent discoveries of trans-Neptunian Pluto-sized objects do not require that we exclude Pluto from the planets. But the obvious alternative, that classificatory revision is a matter of arbitrary choice, is also unpalatable. I argue that this classificatory controversy — which I compare to the controversy about the classification of the platypus — illustrates how our classificatory practices are laden with normative commitments of a distinctive kind. I argue that the “norm-ladenness” of classification has philosophically significant ramifications for how we think about scientific disputes and debates in the metaphysics of classification such as the monism/pluralism debate

    Automatic calculation of thresholds for load dependent condition indicators by modelling of probability distribution functions – maintenance of gearboxes used in mining conveying system

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    Limit values for gearbox vibration-based condition indicators are key to determine in order to be able to estimate moment when object is in a need of maintenance. Further decision making process usually might utilize simple if-then-else rule using established threshold values. If diagnostic data takes the values from the Gaussian distribution, finding the decision boundaries is not difficult. Simplistically, that comes down to standard pattern recognition technique for “good condition” and “bad condition” based on probability density functions (PDFs) of diagnostic data. This situation is becoming more and more complicated when distribution is not Gaussian. Such cases require to develop much more advanced analytically solution. In this paper, we present the case of belt conveyor’s gearbox for which PDFs of diagnostic features overlap each other because of strong influence of time varying operating conditions on spectral features. New approach to automatic threshold recognition has been proposed based on modeling diagnostic features with Weibull distribution and using agglomerative clustering to distinguish classes of technical condition, which leads to determination of thresholds separating them

    A document analysis of the visibility of sustainability in TVE teacher education programme: the case of a Malaysian HEI

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    There has been a global call for institutions of learning to engage in Education for Sustainable Development (ESD) by leading world organisations. Although scholars advocate for an interdisciplinary approach to sustainability, the research literature shows that majority of sustainability issues are addressed through fields such as environmental and developmental education. There has also been a call for the integration of Sustainable Development (SD) in Technical and Vocational Education and Training (TVET) programmes by various scholars and bodies such as the United Nations Education, Scientific and Cultural Organisation (UNESCO). The issue, however, is that Technical and Vocational Education (TVE) programmes are not yet embracing this call to integrate ESD into their programmes. Hence, it is imperative to reiterate the intersection between TVE and SD and how the former can contribute significantly to the SD agenda. Therefore, by completing a qualitative documentary analysis of a TVE programme, using a Malaysian Higher Education Institution (HEI) as a case study, this paper discusses the visibility of sustainability in TVE programmes as well as explores the overarching goal of ESD and why it is especially crucial for TVE. Findings reveal that the concept of sustainability is only barely reflected in the TVE teacher training curriculum. Recommendations for practice change and further research are presented and discussed

    Non-destructive technologies for fruit and vegetable size determination - a review

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    Here, we review different methods for non-destructive horticultural produce size determination, focusing on electronic technologies capable of measuring fruit volume. The usefulness of produce size estimation is justified and a comprehensive classification system of the existing electronic techniques to determine dimensional size is proposed. The different systems identified are compared in terms of their versatility, precision and throughput. There is general agreement in considering that online measurement of axes, perimeter and projected area has now been achieved. Nevertheless, rapid and accurate volume determination of irregular-shaped produce, as needed for density sorting, has only become available in the past few years. An important application of density measurement is soluble solids content (SSC) sorting. If the range of SSC in the batch is narrow and a large number of classes are desired, accurate volume determination becomes important. A good alternative for fruit three-dimensional surface reconstruction, from which volume and surface area can be computed, is the combination of height profiles from a range sensor with a two-dimensional object image boundary from a solid-state camera (brightness image) or from the range sensor itself (intensity image). However, one of the most promising technologies in this field is 3-D multispectral scanning, which combines multispectral data with 3-D surface reconstructio

    The MiSa 1, A Agricultural Machine with Demining Capabilities

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    The MiSa 1 mobile plant by the BIGAT Engineering Office for Processing of Waste Ltd. is a agricultural machine designed to pick up and sift through soil, separate out metal fragments and undergrowth, and replace the cleaned soil. While BIGAT envisions many uses for the MiSa I mobile plant, they are particularly encouraged by its performance as an aid for mine clearance. The MiSa I is capable of clearing specific minefield areas of vegetation that is up to 15 years old, while at the same time sifting through the soil to a depth of 50cm, cleaning the soil of all manner of metal fragments, including ammunition, mines, and other unexploded ordnance (UXO). BIGAT acknowledges that the MiSa I is not appropriate for use on all minefield areas, but is encouraged by the results produced by the machine in tests thus far. The following article sets forth the detailed specifications of the MiSa 1, and examines the ways in which the machine may be used to aid mine clearance operations

    Electrostatic Sensors – Their Principles and Applications

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    Over the past three decades electrostatic sensors have been proposed, developed and utilised for the continuous monitoring and measurement of a range of industrial processes, mechanical systems and clinical environments. Electrostatic sensors enjoy simplicity in structure, cost-effectiveness and suitability for a wide range of installation conditions. They either provide unique solutions to some measurement challenges or offer more cost-effective options to the more established sensors such as those based on acoustic, capacitive, optical and electromagnetic principles. The established or potential applications of electrostatic sensors appear wide ranging, but the underlining sensing principle and resultant system characteristics are very similar. This paper presents a comprehensive review of the electrostatic sensors and sensing systems that have been developed for the measurement and monitoring of a range of process variables and conditions. These include the flow measurement of pneumatically conveyed solids, measurement of particulate emissions, monitoring of fluidised beds, on-line particle sizing, burner flame monitoring, speed and radial vibration measurement of mechanical systems, and condition monitoring of power transmission belts, mechanical wear, and human activities. The fundamental sensing principles together with the advantages and limitations of electrostatic sensors for a given area of applications are also introduced. The technology readiness level for each area of applications is identified and commented. Trends and future development of electrostatic sensors, their signal conditioning electronics, signal processing methods as well as possible new applications are also discussed

    A survey on computer vision technology in Camera Based ETA devices

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    Electronic Travel Aid systems are expected to make impaired persons able to perform their everyday tasks such as finding an object and avoiding obstacles easier. Among ETA devices, Camera Based ETA devices are the new one and with a high potential for helping Visually Impaired Persons. With recent advances in computer science and specially computer vision, Camera Based ETA devices used several computer vision algorithms and techniques such as object recognition and stereo vision in order to help VIP to perform tasks such as reading banknotes, recognizing people and avoiding obstacles. This paper analyses and appraises a number of literatures in this area with focus on stereo vision technique. Finally, after discussing about the methods and techniques used in different literatures, it is concluded that the stereo vision is the best technique for helping VIP in their everyday navigation

    Transient Detection and Classification

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    I provide an incomplete inventory of the astronomical variability that will be found by next-generation time-domain astronomical surveys. These phenomena span the distance range from near-Earth satellites to the farthest Gamma Ray Bursts. The surveys that detect these transients will issue alerts to the greater astronomical community; this decision process must be extremely robust to avoid a slew of ``false'' alerts, and to maintain the community's trust in the surveys. I review the functionality required of both the surveys and the telescope networks that will be following them up, and the role of VOEvents in this process. Finally, I offer some ideas about object and event classification, which will be explored more thoroughly by other articles in these proceedings.Comment: 4 pages. In Proceedings of Hot-wiring the Transient Universe (HTU) 2007. To be published in Astronomische Nachrichten, March 200

    Unit Operations of Particulate Solids

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    Suitable for practicing engineers and engineers in training, this book covers the most important operations involving particulate solids. Through clear explanations of theoretical principles and practical laboratory exercises, the text provides an understanding of the behavior of powders and pulverized systems. It also helps readers develop skills for operating, optimizing, and innovating particle processing technologies and machinery in order to carry out industrial operations. The author explores common bulk solids processing operations, including milling, agglomeration, fluidization, mixing, and solid-fluid separation

    Cognitive networks: brains, internet, and civilizations

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    In this short essay, we discuss some basic features of cognitive activity at several different space-time scales: from neural networks in the brain to civilizations. One motivation for such comparative study is its heuristic value. Attempts to better understand the functioning of "wetware" involved in cognitive activities of central nervous system by comparing it with a computing device have a long tradition. We suggest that comparison with Internet might be more adequate. We briefly touch upon such subjects as encoding, compression, and Saussurean trichotomy langue/langage/parole in various environments.Comment: 16 page
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