Neuromorphic Vision Sensing for CNN-based Action Recognition

Neuromorphic vision sensing (NVS) hardware is now gaining traction as a low-power/high-speed visual sensing technology that circumvents the limitations of conventional active pixel sensing (APS) cameras. While object detection and tracking models have been investigated in conjunction with NVS, there is currently little work on NVS for higher-level semantic tasks, such as action recognition. Contrary to recent work that considers homogeneous transfer between flow domains (optical flow to motion vectors), we propose to embed an NVS emulator into a multi-modal transfer learning framework that carries out heterogeneous transfer from optical flow to NVS. The potential of our framework is showcased by the fact that, for the first time, our NVS-based results achieve comparable action recognition performance to motion-vector or optical-flow based methods (i.e., accuracy on UCF-101 within 8.8% of I3D with optical flow), with the NVS emulator and NVS camera hardware offering 3 to 6 orders of magnitude faster frame generation (respectively) compared to standard Brox optical flow. Beyond this significant advantage, our CNN processing is found to have the lowest total GFLOP count against all competing methods (up to 7.7 times complexity saving compared to I3D with optical flow)

Graph-Based Object Classification for Neuromorphic Vision Sensing

Neuromorphic vision sensing (NVS) devices represent visual information as sequences of asynchronous discrete events (a.k.a., "spikes'") in response to changes in scene reflectance. Unlike conventional active pixel sensing (APS), NVS allows for significantly higher event sampling rates at substantially increased energy efficiency and robustness to illumination changes. However, object classification with NVS streams cannot leverage on state-of-the-art convolutional neural networks (CNNs), since NVS does not produce frame representations. To circumvent this mismatch between sensing and processing with CNNs, we propose a compact graph representation for NVS. We couple this with novel residual graph CNN architectures and show that, when trained on spatio-temporal NVS data for object classification, such residual graph CNNs preserve the spatial and temporal coherence of spike events, while requiring less computation and memory. Finally, to address the absence of large real-world NVS datasets for complex recognition tasks, we present and make available a 100k dataset of NVS recordings of the American sign language letters, acquired with an iniLabs DAVIS240c device under real-world conditions

Towards Quantitative Simulations of High Power Proton Cyclotrons

PSI operates a cyclotron based high intensity proton accelerator routinely at an average beam power of 1.3MW. With this power the facility is at the worldwide forefront of high intensity proton accelerators. The beam current is practically limited by losses at extraction and the resulting activation of accelerator components. Further intensity upgrades and new projects aiming at an even higher average beam power, are only possible if the relative losses can be lowered in proportion, thus keeping absolute losses at a constant level. Maintaining beam losses at levels allowing hands-on maintenance is a primary challenge in any high power proton machine design and operation. In consequence, predicting beam halo at these levels is a great challenge and will be addressed in this paper. High power hadron driver have being used in many disciplines of science and, a growing interest in the cyclotron technology for high power hadron drivers are being observed very recently. This report will briefly introduce OPAL, a tool for precise beam dynamics simulations including 3D space charge. One of OPAL's flavors (OPAL-cycl) is dedicated to high power cyclotron modeling and is explained in greater detail. We then explain how to obtain initial conditions for our PSI Ring cyclotron which still delivers the world record in beam power of 1.3 MW continuous wave (cw). Several crucial steps are explained necessary to be able to predict tails at the level of 3\sigma ... 4\sigma in the PSI Ring cyclotron. We compare our results at the extraction with measurements, obtained with a 1.18 MW cw production beam. Based on measurement data, we develop a simple linear model to predict beam sizes of the extracted beam as a function of intensities and confirm the model with simulations.Comment: Corrections and new figur

HEAT TRANSFER TO IMMERSED COOLING TUBES AND PARTICLES IN A FLUIDIZED BED REACTOR

A simple heat transfer model is utilized to determine the heat transfer coefficients for multiple tubes immersed in an industrial fluidized bed reactor supporting an exothermic reaction. From the temperatures at their outlets, superheating occurs in some blocks of tubes, but not in others. A four-zone heat transfer model is then used to evaluate the axial and lateral temperature differences due to the existence of a bottom un-cooled entrance zone and two cooled zones, corresponding to the regions where superheating does and does not occur

Synthesis of Positron Emission Tomography (PET) Images via Multi-channel Generative Adversarial Networks (GANs)

Positron emission tomography (PET) image synthesis plays an important role, which can be used to boost the training data for computer aided diagnosis systems. However, existing image synthesis methods have problems in synthesizing the low resolution PET images. To address these limitations, we propose multi-channel generative adversarial networks (M-GAN) based PET image synthesis method. Different to the existing methods which rely on using low-level features, the proposed M-GAN is capable to represent the features in a high-level of semantic based on the adversarial learning concept. In addition, M-GAN enables to take the input from the annotation (label) to synthesize the high uptake regions e.g., tumors and from the computed tomography (CT) images to constrain the appearance consistency and output the synthetic PET images directly. Our results on 50 lung cancer PET-CT studies indicate that our method was much closer to the real PET images when compared with the existing methods.Comment: 9 pages, 2 figure

Generalization of hysteresis modeling to anisotropic materials

An extension to the model of hysteresis has been presented earlier which included the effect of anisotropy in the modeling of the anhysteretic magnetization curves of uniaxially anisotropic single crystalline materials. Further exploration of this extension shown here considers different kinds of crystal anisotropy in materials. Theory considers that the differential susceptibility at any given field is determined by the displacement of the prevailing magnetization from the anhysteretic magnetization. Thus, it has been shown that the effect of anisotropy on magnetic hysteresis in materials can be incorporated into the model of hysteresis through the anisotropic anhysteretic. This extension is likely to be particularly useful in the case of hard magnetic materials which exhibit high anisotropy

Étude ethnobotanique et screening phytochimique de Caesalpinia benthamiana (Baill.) Herend. et Zarucchi (Caesalpiniaceae)

Les informations ethnobotaniques obtenues auprès de dix (10) tradithérapeutes du canton N\'Gadié dans le Département d\'Adzopé montrent que l\'utilisation de Caesalpinia benthamiana (Caesalpiniaceae) (Cb) contribue significativement aux soins de santé primaire pour le traitement des troubles de l\'érection. En effet, sur les quinze (15) espèces de plantes médicinales (réparties entre 14 familles) utilisées pour le traitement de diverses pathologies liées aux troubles de l\'érection, Cb est la plus fréquemment prescrite dans ledit canton. Un screening phytochimique réalisé sur cinq (5) extraits bruts des racines de Cb a révélé qu\'elles renferment des stérols, polyterpènes, flavonoïdes, saponines, tannins, sucres réducteurs, coumarines et des protéines.Ethnobotanical Informations obtained beside ten (10) traditional herbalists of the canton N\'Gadie in the Department of Adzope show that the use of Caesalpinia benthamiana(Caesalpiniaceae) (Cb) contributes significantly to primary health cares for the processing of erectile troubles. Indeed, on the fifteen (15) species of plant medicinal (distributed between 14 families) used for the various pathology processing linked to erectile troubles, Cb is the most frequently prescribed in the aforementioned canton. A phytochemical screening realized on five (5) extracted crude of roots of Cb has revealed that they contain the sterols, polyterpenes, flavonoids, saponines, tannins, reducing sugars, coumarins and proteins. Keywords: pharmacopée traditionnelle, Côte d\'Ivoire, Adzopé, screening phytochimique, érection, Caesalpinia benthamiana(Caesalpiniaceae)/traditional pharmacopoeia, Côte d'Ivoire, Adzope, erection, Caesalpinia benthamiana (Caesalpiniaceae)Sciences & Nature Vol. 4 (2) 2007: pp. 217-22