4,218 research outputs found

    Robust Minutiae Extractor: Integrating Deep Networks and Fingerprint Domain Knowledge

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    We propose a fully automatic minutiae extractor, called MinutiaeNet, based on deep neural networks with compact feature representation for fast comparison of minutiae sets. Specifically, first a network, called CoarseNet, estimates the minutiae score map and minutiae orientation based on convolutional neural network and fingerprint domain knowledge (enhanced image, orientation field, and segmentation map). Subsequently, another network, called FineNet, refines the candidate minutiae locations based on score map. We demonstrate the effectiveness of using the fingerprint domain knowledge together with the deep networks. Experimental results on both latent (NIST SD27) and plain (FVC 2004) public domain fingerprint datasets provide comprehensive empirical support for the merits of our method. Further, our method finds minutiae sets that are better in terms of precision and recall in comparison with state-of-the-art on these two datasets. Given the lack of annotated fingerprint datasets with minutiae ground truth, the proposed approach to robust minutiae detection will be useful to train network-based fingerprint matching algorithms as well as for evaluating fingerprint individuality at scale. MinutiaeNet is implemented in Tensorflow: https://github.com/luannd/MinutiaeNetComment: Accepted to International Conference on Biometrics (ICB 2018

    Neuromodulation: present and emerging methods.

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    Neuromodulation has wide ranging potential applications in replacing impaired neural function (prosthetics), as a novel form of medical treatment (therapy), and as a tool for investigating neurons and neural function (research). Voltage and current controlled electrical neural stimulation (ENS) are methods that have already been widely applied in both neuroscience and clinical practice for neuroprosthetics. However, there are numerous alternative methods of stimulating or inhibiting neurons. This paper reviews the state-of-the-art in ENS as well as alternative neuromodulation techniques-presenting the operational concepts, technical implementation and limitations-in order to inform system design choices

    Very small grains in the Milky Way and external galaxies

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    These studies of the infrared colors of reflection nebulae, HL HI clouds, HII regions and external galaxies have shown the following results. Different classes of objects locate in different regions on the R vs F sub v (60)/F sub v (100) diagram. This is determined both by differences in dust properties and by differences in the illuminating radiation field. For example, HL clouds and reflection nebulae almost have the same behavior since both are in the diffuse Interstellar Medium (ISM) and can be expected to have similar grain populations; the small difference in their infrared colors can be explained by the difference of the illuminating radiation field. On the other hand, the dramatic difference of R=vF sub v (12)/F sub v (far IR) between HII region and diffuse ISM may be due to the destruction of the Very Small Grain (VSG) component in the HII regions, although radiation transfer effects may play a part as well. The ratio R=vF sub v (12)/F sub v (far IR) is approximately constant in normal spiral galaxies. This implies that the mass ratio b=Mass (VSG)/Mass (dust) does not vary greatly from one galaxy to another

    Assessment of different urban traffic control strategy impacts on vehicle emissions

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    This paper investigates the influence of traffic signal control strategy on vehicle emissions, vehicle journey time and total throughput flow within a single isolated four-armed junction. Two pre-timed signal plans are considered, one with two-stages involving permissive-only opposing turns and the other with four-stages which has no conflicting traffic. Additionally, the increase in efficiency by utilising actuated signal timing where green time is re-optimised as flow values vary is investigated. A microscopic traffic simulation model is used to model flows and AIRE (Analysis of Instantaneous Road Emissions) microscopic emissions model is utilised to out- put emission levels from the flow data. A simple junction model shows that the two-stage signal plan is more efficient in both emis- sions and journey time. However, as the level of opposed turning vehicles and conflicting movement increases, the two-stage model moves to being the inferior signal plan choice and the four-stage plan outputs fewer emissions than the two-stage plan. A real-world example of a four-armed junction has been used in this study and from the traffic survey data and existing junction layout; it is rec- ommended that a two-stage plan is used as it produces lower amounts of emissions and shorter journey times compared to a four-stage plan. The results also show that nitrogen oxides (NOx) are the most sensitive to changes in flow followed by carbon dioxide (CO2), Black Carbon and then particulate matter (PM10)

    Optimal Inter-Release Time between Sequentially Released Products

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    Marketers routinely use timing as a segmentation device through sequential product releases. While there has been much theoretical research on the optimal introduction strategy of sequential releases, there is little empirical research on this problem. This paper develops an econometric model to empirically solve the inter-release timing problem: it involves (1) developing and estimating a structural model of consumers’ choice for sequentially released products and (2) using the estimates of the structural model to solve for the optimal inter-release time. The empirical application focuses on the movie industry, where we specifically address the issue of the inter-release time between a theatrical movie and its DVD version. We find that consumers are indeed forward looking; a shrinking movie-DVD release window does negatively impact box office revenues, but there is a tradeoff in that there is greater residual buzz from the movie marketing that supports the sales of DVD due to the shorter time window. This leads to an inverted U shaped relationship between movie-DVD release window and revenues, and the theater-DVD window that maximizes industry revenue for the average movie during the data period is 2.5 months

    Contact of Single Asperities with Varying Adhesion: Comparing Continuum Mechanics to Atomistic Simulations

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    Atomistic simulations are used to test the equations of continuum contact mechanics in nanometer scale contacts. Nominally spherical tips, made by bending crystals or cutting crystalline or amorphous solids, are pressed into a flat, elastic substrate. The normal displacement, contact radius, stress distribution, friction and lateral stiffness are examined as a function of load and adhesion. The atomic scale roughness present on any tip made of discrete atoms is shown to have profound effects on the results. Contact areas, local stresses, and the work of adhesion change by factors of two to four, and the friction and lateral stiffness vary by orders of magnitude. The microscopic factors responsible for these changes are discussed. The results are also used to test methods for analyzing experimental data with continuum theory to determine information, such as contact area, that can not be measured directly in nanometer scale contacts. Even when the data appear to be fit by continuum theory, extracted quantities can differ substantially from their true values

    Remission of obesity among a nationally representative sample of US children

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147066/1/ijpo12457.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147066/2/ijpo12457_am.pd
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