99 research outputs found

    A Cognitive Framework for Understanding Counterintuitive Stories

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    Stories containing counterintuitive concepts are prevalent in a variety of cultural forms including folktales, TV and radio commercials, and religious parables. Cognitive scientists such as Boyer suggest that this may be because counterintuitive concepts are surprising and more memorable for people and therefore are more likely to become widespread in a culture. How and why people remember such concepts has been subject of some debate. This paper presents studies designed to test predictions of the context-based model of counterintuitive story understanding

    Active User Authentication for Smartphones: A Challenge Data Set and Benchmark Results

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    In this paper, automated user verification techniques for smartphones are investigated. A unique non-commercial dataset, the University of Maryland Active Authentication Dataset 02 (UMDAA-02) for multi-modal user authentication research is introduced. This paper focuses on three sensors - front camera, touch sensor and location service while providing a general description for other modalities. Benchmark results for face detection, face verification, touch-based user identification and location-based next-place prediction are presented, which indicate that more robust methods fine-tuned to the mobile platform are needed to achieve satisfactory verification accuracy. The dataset will be made available to the research community for promoting additional research.Comment: 8 pages, 12 figures, 6 tables. Best poster award at BTAS 201

    On the Effects of Code Cardinality for TH-PPM Ultra Wideband Systems, Journal of Telecommunications and Information Technology, 2008, nr 4

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    This paper demonstrates the effects of code cardinality at transmitter section on bit error rate (BER) performance of time hopping pulse position modulation (TH-PPM) based ultra wideband (UWB) indoor radio communication. In the transmitter, different code cardinality values have been chosen and correspondingly the effects on BER of the system have been investigated. The recently accepted IEEE 802.15.3a model of the UWB channel has been used as the propaga- tion channel model in indoor environment. Results show that the system BER performance is significantly dependent on the code cardinality value of time hopping code. For such higher code cardinality values as in the range from 30 to 50, the BER performance degrades severely. Finally, code cardinality in the range from 10 to 15 has been recommended for TH-PPM system in UWB indoor communications providing better BER performance for the same system data rate requirement

    Optimum receiver performance of TH-PPM ultra wideband system in multiple user interference, Journal of Telecommunications and Information Technology, 2007, nr 4

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    This paper demonstrates optimum receiver performance in terms of bit error rate (BER) for time hopping pulse position modulation (TH-PPM) ultra wideband (UWB) system in multiple user interference environment for indoor radio communication. Equal gain combining and selective gain combining have been demonstrated in terms of ideal RAKE (ARAKE), selective RAKE (SRAKE) and partial RAKE (PRAKE) receiver performances. The recently accepted IEEE 802.15.3a model of the UWB channel has been used to describe UWB propagation in indoor environment. Two channel scenarios named CM-1 and CM-3 for IEEE 802.15.3a channel model have been investigated principally. Finally, this paper concludes with an approximation of equivalence of number of fingers in SRAKE and PRAKE receivers as well as an indication of SNR gains achievable as the RAKE finger number is increased, espe- cially with multiple user interference (MUI), for a 16.6 Mbit/s UWB system

    Statistical dynamics of religion evolutions

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    A religion affiliation can be considered as a "degree of freedom" of an agent on the human genre network. A brief review is given on the state of the art in data analysis and modelization of religious "questions" in order to suggest and if possible initiate further research, ... after using a "statistical physics filter". We present a discussion of the evolution of 18 so called religions, as measured through their number of adherents between 1900 and 2000. Some emphasis is made on a few cases presenting a minimum or a maximum in the investigated time range, - thereby suggesting a competitive ingredient to be considered, beside the well accepted "at birth" attachement effect. The importance of the "external field" is still stressed through an Avrami late stage crystal growth-like parameter. The observed features and some intuitive interpretations point to opinion based models with vector, rather than scalar, like agents

    Memory for expectation-violating concepts:The effects of agents and cultural familiarity

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    Previous research has shown that ideas which violate our expectations, such as schema-inconsistent concepts, enjoy privileged status in terms of memorability. In our study, memory for concepts that violate cultural (cultural schema-level) expectations (e.g., "illiterate teacher", "wooden bottle", or "thorny grass") versus domain-level (ontological) expectations (e.g., "speaking cat", "jumping maple", or "melting teacher") was examined. Concepts that violate cultural expectations, or counter-schematic, were remembered to a greater extent compared with concepts that violate ontological expectations and with intuitive concepts (e.g., "galloping pony", "drying orchid", or "convertible car"), in both immediate recall, and delayed recognition tests. Importantly, concepts related to agents showed a memory advantage over concepts not pertaining to agents, but this was true only for expectation-violating concepts. Our results imply that intuitive, everyday concepts are equally attractive and memorable regardless of the presence or absence of agents. However, concepts that violate our expectations (cultural-schema or domain-level) are more memorable when pertaining to agents (humans and animals) than to non-agents (plants or objects/artifacts). We conclude that due to their evolutionary salience, cultural ideas which combine expectancy violations and the involvement of an agent are especially memorable and thus have an enhanced probability of being successfully propagated. © 2014 Porubanova et al

    The Effect of Fluid Flow Shear Stress and Substrate Stiffness on Yes-Associated Protein (YAP) Activity and Osteogenesis in Murine Osteosarcoma Cells

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    Osteosarcoma (OS) is an aggressive bone cancer originating in the mesenchymal lineage. Prognosis for metastatic disease is poor, with a mortality rate of approximately 40%; OS is an aggressive disease for which new treatments are needed. All bone cells are sensitive to their mechanical/ physical surroundings and changes in these surroundings can affect their behavior. However, it is not well understood how OS cells specifically respond to fluid movement, or substrate stiffness—two stimuli of relevance in the tumor microenvironment. We used cells from spontaneous OS tumors in a mouse engineered to have a bone-specific knockout of pRb-1 and p53 in the osteoblast lineage. We silenced Sox2 (which regulates YAP) and tested the effect of fluid flow shear stress (FFSS) and substrate stiffness on YAP expression/activity—which was significantly reduced by loss of Sox2, but that effect was reversed by FFSS but not by substrate stiffness. Osteogenic gene expression was also reduced in the absence of Sox2 but again this was reversed by FFSS and remained largely unaffected by substrate stiffness. Thus we described the effect of two distinct stimuli on the mechanosensory and osteogenic profiles of OS cells. Taken together, these data suggest that modulation of fluid movement through, or stiffness levels within, OS tumors could represent a novel consideration in the development of new treatments to prevent their progression

    Advancing the use of passive sampling in risk assessment and management of contaminated sediments: Results of an international passive sampling inter-laboratory comparison

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    This work presents the results of an international interlaboratory comparison on ex situ passive sampling in sediments. The main objectives were to map the state of the science in passively sampling sediments, identify sources of variability, provide recommendations and practical guidance for standardized passive sampling, and advance the use of passive sampling in regulatory decision making by increasing confidence in the use of the technique. The study was performed by a consortium of 11 laboratories and included experiments with 14 passive sampling formats on 3 sediments for 25 target chemicals (PAHs and PCBs). The resulting overall interlaboratory variability was large (a factor of ∼10), but standardization of methods halved this variability. The remaining variability was primarily due to factors not related to passive sampling itself, i.e., sediment heterogeneity and analytical chemistry. Excluding the latter source of variability, by performing all analyses in one laboratory, showed that passive sampling results can have a high precision and a very low intermethod variability
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