2,902 research outputs found

    Heavy electrons: Electron droplets generated by photogalvanic and pyroelectric effects

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    Electron clusters, X-rays and nanosecond radio-frequency pulses are produced by 100 mW continuous-wave laser illuminating ferroelectric crystal of LiNbO_3. A long-living stable electron droplet with the size of about 100 mcm has freely moved with the velocity 0.5 cm/s in the air near the surface of the crystal experiencing the Earth gravitational field. The microscopic model of cluster stability, which is based on submicroscopic mechanics developed in the real physical space, is suggested. The role of a restraining force plays the inerton field, a substructure of the particles' matter waves, which a solitary one can elastically withstand the Coulomb repulsion of electrons. It is shown that electrons in the droplet are heavy electrons whose mass at least 1 million of times exceeds the rest mass of free electron. Application for X-ray imaging and lithography is discussed.Comment: 15 p., 3 fig

    Complexity and Action: Reflections on Decision Making and Cybernetics.

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    This paper highlights some theoretical and epistemological reflections about the relevance of action for managerial studies. These reflections show how the cybernetic paradigm of complexity management can be used for better decision making that unites knowledge and action in a comprising, dynamic, and evolving approach. Cybernetics can help to overcome the fear of decision making in the face of uncertainty in complex scenarios, and can be an effective tool for improving the viability and competitiveness of firms in the twenty-first century

    Information Theory’s failure in neuroscience: on the limitations of cybernetics

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    In Cybernetics (1961 Edition), Professor Norbert Wiener noted that “The role of information and the technique of measuring and transmitting information constitute a whole discipline for the engineer, for the neuroscientist, for the psychologist, and for the sociologist”. Sociology aside, the neuroscientists and the psychologists inferred “information transmitted” using the discrete summations from Shannon Information Theory. The present author has since scrutinized the psychologists’ approach in depth, and found it wrong. The neuroscientists’ approach is highly related, but remains unexamined. Neuroscientists quantified “the ability of [physiological sensory] receptors (or other signal-processing elements) to transmit information about stimulus parameters”. Such parameters could vary along a single continuum (e.g., intensity), or along multiple dimensions that altogether provide a Gestalt – such as a face. Here, unprecedented scrutiny is given to how 23 neuroscience papers computed “information transmitted” in terms of stimulus parameters and the evoked neuronal spikes. The computations relied upon Shannon’s “confusion matrix”, which quantifies the fidelity of a “general communication system”. Shannon’s matrix is square, with the same labels for columns and for rows. Nonetheless, neuroscientists labelled the columns by “stimulus category” and the rows by “spike-count category”. The resulting “information transmitted” is spurious, unless the evoked spike-counts are worked backwards to infer the hypothetical evoking stimuli. The latter task is probabilistic and, regardless, requires that the confusion matrix be square. Was it? For these 23 significant papers, the answer is No

    Investigating e-business practices in tourism :a comparative analysis of three countries

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    This study examined the behaviour of tourist companies in relation to the adoption of e-business technologies and applications. The study aimed to identify groups of companies with homogenous behaviour among three European countries (Greece, Portugal and Norway). Based on data from a European survey, the study employed two-step cluster analysis which revealed 14 clusters of common behaviour (five clusters in Greece, five in Portugal and four in Norway). These clusters were named as: Leaders’ ‘Technology Experts’, ‘Fast Adopters’ ‘Beginners’, ‘Late Adopters’. In Norway, the group ‘Late Adopters’ also included companies characterised as ‘Beginners’ in the other two countries. We suggest further investigation among European countries in order to reveal more groups of similar behaviour toward e-business adoption

    Homunculus strides again: why ‘information transmitted’ in neuroscience tells us nothing

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    Purpose – For half a century, neuroscientists have used Shannon Information Theory to calculate “information transmitted,” a hypothetical measure of how well neurons “discriminate” amongst stimuli. Neuroscientists’ computations, however, fail to meet even the technical requirements for credibility. Ultimately, the reasons must be conceptual. That conclusion is confirmed here, with crucial implications for neuroscience. The paper aims to discuss these issues. Design/methodology/approach – Shannon Information Theory depends upon a physical model, Shannon’s “general communication system.” Neuroscientists’ interpretation of that model is scrutinized here. Findings – In Shannon’s system, a recipient receives a message composed of symbols. The symbols received, the symbols sent, and their hypothetical occurrence probabilities altogether allow calculation of “information transmitted.” Significantly, Shannon’s system’s “reception” (decoding) side physically mirrors its “transmission” (encoding) side. However, neurons lack the “reception” side; neuroscientists nonetheless insisted that decoding must happen. They turned to Homunculus, an internal humanoid who infers stimuli from neuronal firing. However, Homunculus must contain a Homunculus, and so on ad infinitum – unless it is super-human. But any need for Homunculi, as in “theories of consciousness,” is obviated if consciousness proves to be “emergent.” Research limitations/implications – Neuroscientists’ “information transmitted” indicates, at best, how well neuroscientists themselves can use neuronal firing to discriminate amongst the stimuli given to the research animal. Originality/value – A long-overdue examination unmasks a hidden element in neuroscientists’ use of Shannon Information Theory, namely, Homunculus. Almost 50 years’ worth of computations are recognized as irrelevant, mandating fresh approaches to understanding “discriminability.

    Modern information literacy innovates library by systems thinking

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    Information literacy enables library users to well use modern sources of information in order to both create and apply knowledge. This competency can be more or less holistic with the level of holism having crucial consequences.To describe this particular need for holism systems thinking and information literacy are discussed, especially in relation to their creative and innovative use. We propose a Dialectical Systems Theory which can support this endeavor
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