518 research outputs found

    A report on Greek history education

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    Segmentation-Aware Convolutional Networks Using Local Attention Masks

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    We introduce an approach to integrate segmentation information within a convolutional neural network (CNN). This counter-acts the tendency of CNNs to smooth information across regions and increases their spatial precision. To obtain segmentation information, we set up a CNN to provide an embedding space where region co-membership can be estimated based on Euclidean distance. We use these embeddings to compute a local attention mask relative to every neuron position. We incorporate such masks in CNNs and replace the convolution operation with a "segmentation-aware" variant that allows a neuron to selectively attend to inputs coming from its own region. We call the resulting network a segmentation-aware CNN because it adapts its filters at each image point according to local segmentation cues. We demonstrate the merit of our method on two widely different dense prediction tasks, that involve classification (semantic segmentation) and regression (optical flow). Our results show that in semantic segmentation we can match the performance of DenseCRFs while being faster and simpler, and in optical flow we obtain clearly sharper responses than networks that do not use local attention masks. In both cases, segmentation-aware convolution yields systematic improvements over strong baselines. Source code for this work is available online at http://cs.cmu.edu/~aharley/segaware

    Deep Learning for Semantic Part Segmentation with High-Level Guidance

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    In this work we address the task of segmenting an object into its parts, or semantic part segmentation. We start by adapting a state-of-the-art semantic segmentation system to this task, and show that a combination of a fully-convolutional Deep CNN system coupled with Dense CRF labelling provides excellent results for a broad range of object categories. Still, this approach remains agnostic to high-level constraints between object parts. We introduce such prior information by means of the Restricted Boltzmann Machine, adapted to our task and train our model in an discriminative fashion, as a hidden CRF, demonstrating that prior information can yield additional improvements. We also investigate the performance of our approach ``in the wild'', without information concerning the objects' bounding boxes, using an object detector to guide a multi-scale segmentation scheme. We evaluate the performance of our approach on the Penn-Fudan and LFW datasets for the tasks of pedestrian parsing and face labelling respectively. We show superior performance with respect to competitive methods that have been extensively engineered on these benchmarks, as well as realistic qualitative results on part segmentation, even for occluded or deformable objects. We also provide quantitative and extensive qualitative results on three classes from the PASCAL Parts dataset. Finally, we show that our multi-scale segmentation scheme can boost accuracy, recovering segmentations for finer parts.Comment: 11 pages (including references), 3 figures, 2 table

    Learning morphological phenomena of Modern Greek an exploratory approach

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    This paper presents a computational model for the description of concatenative morphological phenomena of modern Greek (such as inflection, derivation and compounding) to allow learners, trainers and developers to explore linguistic processes through their own constructions in an interactive openā€ended multimedia environment. The proposed model introduces a new language metaphor, the ā€˜puzzleā€metaphorā€™ (similar to the existing ā€˜turtleā€metaphorā€™ for concepts from mathematics and physics), based on a visualized unificationā€like mechanism for pattern matching. The computational implementation of the model can be used for creating environments for learning through design and learning by teaching

    Approaching mythology in the history curriculum of compulsory education in Greece

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    Myth can be a first step in historicizing the past and at the same time in appreciating ancient cultures and developing the essential skill of empathy. A main objective of the history curriculum for the third grade of primary school in Greece is for children at 8 and 9 years old to familiarize themselves with the basic cultural elements of the origins of Greek, European and global civilization. Ancient Greek myths are taught using references and links to the myths of other peoples and cultures, and by identifying similarities and differences in the interpretation of the world within the framework of a multi-perspective, intercultural approach. Myths also depict the relationship between man and nature. They constitute manā€™s attempt to interpret the physical and social environment. In addition, myths present the relationship between man and the divine in the early stages of cultural evolution, and at the same time provide evidence of the culture of a historical period. Pupils become aware of the fact that myths used to have a symbolic and ritualistic function, which aimed to initiate younger members into the acceptable practices and values of their community. Myths provided meaningful models of action (exempla) through their allegorical nature. Moreover, myths facilitate the analysis of human behaviour by introducing the schema of cause and effect. Mythical thought seeks to understand causality, which is also the primary aim of science. In this sense, mythical discourse is connected to scientific discourse. Within the framework of a methodological approach based on these theoretical assumptions, this paper also includes a presentation of educational activities and pupilsā€™ perceptions as part of a survey conducted in a third-grade primary school class in Greece

    Some Advances in Nonlinear Speech Modeling Using Modulations, Fractals, and Chaos

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    In this paper we briefly summarize our on-going work on modeling nonlinear structures in speech signals, caused by modulation and turbulence phenomena, using the theories of modulation, fractals, and chaos as well as suitable nonlinear signal analysis methods. Further, we focus on two advances: i) AM-FM modeling of fricative sounds with random modulation signals of the 1/f-noise type and ii) improved methods for speech analysis and prediction on reconstructed multidimensional attractors. 1

    Development of an optimized method for the detection of airborne viruses with real-time PCR analysis

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    <p>Abstract</p> <p>Background</p> <p>Airborne viruses remain one of the major public health issues worldwide. Detection and quantification of airborne viruses is essential in order to provide information regarding public health risk assessment.</p> <p>Findings</p> <p>In this study, an optimized new, simple, low cost method for sampling of airborne viruses using Low Melting Agarose (LMA) plates and a conventional microbial air sampling device has been developed. The use of LMA plates permits the direct nucleic acids extraction of the captured viruses without the need of any preliminary elution step. Molecular detection and quantification of airborne viruses is performed using real-time quantitative (RT-)PCR (Q(RT-)PCR) technique. The method has been tested using Adenoviruses (AdVs) and Noroviruses (NoVs) GII, as representative DNA and RNA viruses, respectively. Moreover, the method has been tested successfully in outdoor experiments, by detecting and quantifying human adenoviruses (HAdVs) in the airborne environment of a wastewater treatment plant.</p> <p>Conclusions</p> <p>The great advantage of LMA is that nucleic acids extraction is performed directly on the LMA plates, while the eluted nucleic acids are totally free of inhibitory substances. Coupled with QPCR the whole procedure can be completed in less than three (3) hours.</p

    BLSM: A Bone-Level Skinned Model of the Human Mesh

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    We introduce BLSM, a bone-level skinned model of the human body mesh where bone scales are set prior to template synthesis, rather than the common, inverse practice. BLSM first sets bone lengths and joint angles to specify the skeleton, then specifies identity-specific surface variation, and finally bundles them together through linear blend skinning. We design these steps by constraining the joint angles to respect the kinematic constraints of the human body and by using accurate mesh convolution-based networks to capture identity-specific surface variation. We provide quantitative results on the problem of reconstructing a collection of 3D human scans, and show that we obtain improvements in reconstruction accuracy when comparing to a SMPL-type baseline. Our decoupled bone and shape representation also allows for out-of-box integration with standard graphics packages like Unity, facilitating full-body AR effects and image-driven character animation. Additional results and demos are available from the project webpage: http://arielai.com/blsm

    DenseReg: fully convolutional dense shape regression in-the-wild

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    In this paper we propose to learn a mapping from image pixels into a dense template grid through a fully convolutional network. We formulate this task as a regression problem and train our network by leveraging upon manually annotated facial landmarks ā€œin-the-wildā€. We use such landmarks to establish a dense correspondence field between a three-dimensional object template and the input image, which then serves as the ground-truth for training our regression system. We show that we can combine ideas from semantic segmentation with regression networks, yielding a highly-accurate ā€˜quantized regressionā€™ architecture. Our system, called DenseReg, allows us to estimate dense image-to-template correspondences in a fully convolutional manner. As such our network can provide useful correspondence information as a stand-alone system, while when used as an initialization for Statistical Deformable Models we obtain landmark localization results that largely outperform the current state-of-the-art on the challenging 300W benchmark. We thoroughly evaluate our method on a host of facial analysis tasks, and demonstrate its use for other correspondence estimation tasks, such as the human body and the human ear. DenseReg code is made available at http://alpguler.com/DenseReg.html along with supplementary materials
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