9,740 research outputs found

    An automatic deep learning approach for coronary artery calcium segmentation

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    Coronary artery calcium (CAC) is a significant marker of atherosclerosis and cardiovascular events. In this work we present a system for the automatic quantification of calcium score in ECG-triggered non-contrast enhanced cardiac computed tomography (CT) images. The proposed system uses a supervised deep learning algorithm, i.e. convolutional neural network (CNN) for the segmentation and classification of candidate lesions as coronary or not, previously extracted in the region of the heart using a cardiac atlas. We trained our network with 45 CT volumes; 18 volumes were used to validate the model and 56 to test it. Individual lesions were detected with a sensitivity of 91.24%, a specificity of 95.37% and a positive predicted value (PPV) of 90.5%; comparing calcium score obtained by the system and calcium score manually evaluated by an expert operator, a Pearson coefficient of 0.983 was obtained. A high agreement (Cohen's k = 0.879) between manual and automatic risk prediction was also observed. These results demonstrated that convolutional neural networks can be effectively applied for the automatic segmentation and classification of coronary calcifications

    An adaptive stigmergy-based system for evaluating technological indicator dynamics in the context of smart specialization

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    Regional innovation is more and more considered an important enabler of welfare. It is no coincidence that the European Commission has started looking at regional peculiarities and dynamics, in order to focus Research and Innovation Strategies for Smart Specialization towards effective investment policies. In this context, this work aims to support policy makers in the analysis of innovation-relevant trends. We exploit a European database of the regional patent application to determine the dynamics of a set of technological innovation indicators. For this purpose, we design and develop a software system for assessing unfolding trends in such indicators. In contrast with conventional knowledge-based design, our approach is biologically-inspired and based on self-organization of information. This means that a functional structure, called track, appears and stays spontaneous at runtime when local dynamism in data occurs. A further prototyping of tracks allows a better distinction of the critical phenomena during unfolding events, with a better assessment of the progressing levels. The proposed mechanism works if structural parameters are correctly tuned for the given historical context. Determining such correct parameters is not a simple task since different indicators may have different dynamics. For this purpose, we adopt an adaptation mechanism based on differential evolution. The study includes the problem statement and its characterization in the literature, as well as the proposed solving approach, experimental setting and results.Comment: mail: [email protected]

    Continuous variable cloning via network of parametric gates

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    We propose an experimental scheme for the cloning machine of continuous quantum variables through a network of parametric amplifiers working as input-output four-port gates.Comment: 4 pages, 2 figures. To appear on Phys. Rev. Let

    Entangling macroscopic diamonds at room temperature: Bounds on the continuous-spontaneous-localization parameters

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    A recent experiment [K. C. Lee et al., Science 334, 1253 (2011)] succeeded in detecting entanglement between two macroscopic specks of diamonds, separated by a macroscopic distance, at room temperature. This impressive results is a further confirmation of the validity of quantum theory in (at least parts of) the mesoscopic and macroscopic domain, and poses a challenge to collapse models, which predict a violation of the quantum superposition principle, which is the bigger the larger the system. We analyze the experiment in the light of such models. We will show that the bounds placed by experimental data are weaker than those coming from matter-wave interferometry and non-interferometric tests of collapse models.Comment: 7 pages, 3 figures, v2: close to the published version, LaTe

    The three-body recombination of a condensed Bose gas near a Feshbach resonance

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    In this paper, we study the three-body recombination rate of a homogeneous dilute Bose gas with a Feshbach resonance at zero temperature. The ground state and excitations of this system are obtained. The three-body recombination in the ground state is due to the break-up of an atom pair in the quantum depletion and the formation of a molecule by an atom from the broken pair and an atom from the condensate. The rate of this process is in good agreement with the experiment on 23^{23}Na in a wide range of magnetic fields.Comment: 10 pages, 2 figures, to be published in Phys. Rev.

    Perencanaan Suksesi Pada Perusahaan Keluarga Di Kota Denpasar

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    The main objective of this study was to determine the succession planning a family business in the city of Denpasar . This research was conducted at the family business in Denpasar Data were analyzed qualitatively and quantitatively using a Likert scale and to determine the factors that influence succession planning in family business were analyzed with multiple linear regression using SPSS . The results found that succession planning in family business in the city of Denpasar has done well based on considerations mean value of 4:07 per cent . Values and characteristics successor positive effect on corporate succession planning families business in the city of Denpasar
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