321 research outputs found

    Using Convolutional Neural Networks for the Helicity Classification of Magnetic Fields

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    The presence of non-zero helicity in intergalactic magnetic fields is a smoking gun for their primordial origin since they have to be generated by processes that break CP invariance. As an experimental signature for the presence of helical magnetic fields, an estimator QQ based on the triple scalar product of the wave-vectors of photons generated in electromagnetic cascades from, e.g., TeV blazars, has been suggested previously. We propose to apply deep learning to helicity classification employing Convolutional Neural Networks and show that this method outperforms the QQ estimator.Comment: 14 pages, extended version of a contribution to the proceedings of the 37.th ICRC 202

    Clinical and histopathological observations of autologous bone marrow stromal cells implantation on the regeneration of sciatic nerve neurotmesis in rabbit

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    The peripheral nerve injuries (PNI) is due to stretching and laceration. Therefore, the epineural repair technique is currently accepted as a standard method for peripheral nerve repair. Thirty-two (32) rabbits were divided equally into perineural nerve sutures as control group (CG) and bone marrow stromal cells (BMSCs) as the treatment group (TG). The aim of this study was to investigate the effect of the autologous BMSCs implantation on the regeneration of sciatic nerve neurotmesis in rabbits. There was significant improvement (p<0.05) of the motor and sensory functions in the TG animals as compared to the CG. Histopathological examinations of the proximal nerve stump in the CG showed mild adherence surrounding an anastomosed area, few vacuolation and plenty of collagen at the peri and epineurium. The anastomosed site showed the degeneration, disorientation and giant cell surrounding the stitches, while intraneurial scar tissues were seen in the distal segment at the 112th post operation day (POD). The histopathology of TG showed the activated Schwann cells, good myelination, minimum scar tissue, good orientation and remarkable angiogenesis at the 112th POD. BMSCs are capable of improving the motor and sensory functions and significantly promote the regeneration of sciatic nerve neurotmesis in rabbits.Key words: Clinical, histopathological, bone marrow stromal cells (BMSCs), neurotmesis, sciatic nerve, rabbit

    Robotic Harvesting of Fruiting Vegetables: A Simulation Approach in V-REP, ROS and MATLAB

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    In modern agriculture, there is a high demand to move from tedious manual harvesting to a continuously automated operation. This chapter reports on designing a simulation and control platform in V-REP, ROS, and MATLAB for experimenting with sensors and manipulators in robotic harvesting of sweet pepper. The objective was to provide a completely simulated environment for improvement of visual servoing task through easy testing and debugging of control algorithms with zero damage risk to the real robot and to the actual equipment. A simulated workspace, including an exact replica of different robot manipulators, sensing mechanisms, and sweet pepper plant, and fruit system was created in V-REP. Image moment method visual servoing with eye-in-hand configuration was implemented in MATLAB, and was tested on four robotic platforms including Fanuc LR Mate 200iD, NOVABOT, multiple linear actuators, and multiple SCARA arms. Data from simulation experiments were used as inputs of the control algorithm in MATLAB, whose outputs were sent back to the simulated workspace and to the actual robots. ROS was used for exchanging data between the simulated environment and the real workspace via its publish-and-subscribe architecture. Results provided a framework for experimenting with different sensing and acting scenarios, and verified the performance functionality of the simulator

    Effects of omental pedicle transposition on regeneration of neurotmesis sciatic nerve in rabbit

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    The present study was aimed at providing an understanding of the role of omental pedicle transposition in peripheral nerve regeneration by utilizing an established rabbit sciatic nerve regeneration model. Twelve adult New Zealand White rabbits (2-2.3kg) were divided into two groups (n=6) and acclimatized for 3 weeks. Complete blood examination, liver and kidney function tests were carried out during this period. In Group A, an end-to-end of sciatic nerve segment anastomosis was done, while that of Group B, the nerve anastomosis wrapped with omental pedicle was performed. The nerve specimens were collected from both groups for histopathological and ultrastructural evaluation after 16 weeks post surgery. Results showed that omental pedicle transpositioned (Group B) had more newly developed nerve fibres and less scar tissue. Ultrastructural examinations showed neuronal sprouting, whereas directions of regenerative nerve fibres were intraneural, but in the end-to-end anastomosis of group B showed that some of nerve fibres had extraneural

    An enhanced lossless compression with cryptography hybrid mechanism for ECG biomedical signal monitoring

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    Due to their use in daily life situation, demand for remote health applications and e-health monitoring equipment is growing quickly. In this phase, for fast diagnosis and therapy, information can be transferred from the patient to the distant clinic. Nowadays, the most chronic disease is cardiovascular diseases (CVDs). However, the storage and transmission of the ECG signal, consumes more energy, bandwidth and data security which is faced many challenges. Hence, in this work, we present a combined approach for ECG data compression and cryptography. The compression is performed using adaptive Huffman encoding and encrypting is done using AES (CBC) scheme with a 256-bit key. To increase the security, we include Diffie-Hellman Key exchange to authenticate the receiver, RSA key generation for encrypting and decrypting the data. Experimental results show that the proposed approach achieves better performance in terms of compression and encryption on MIT-BIH ECG dataset

    Implementation of variational iteration method for various types of linear and nonlinear partial differential equations

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    There are various linear and nonlinear one-dimensional partial differential equations that are the focus of this research. There are a large number of these equations that cannot be solved analytically or precisely. The evaluation of nonlinear partial differential equations, even if analytical solutions exist, may be problematic. Therefore, it may be necessary to use approximate analytical methodologies to solve these issues. As a result, a more effective and accurate approach must be investigated and analyzed. It is shown in this study that the Lagrange multiplier may be used to get an ideal value for parameters in a functional form and then used to construct an iterative series solution. Linear and nonlinear partial differential equations may both be solved using the variational iteration method (VIM) method, thanks to its high computing power and high efficiency. Decoding and analyzing possible Korteweg-De-Vries, Benjamin, and Airy equations demonstrates the method’s ability. With just a few iterations, the produced findings are very effective, precise, and convergent to the exact answer. As a result, solving nonlinear equations using VIM is regarded as a viable option

    Effect of friction and shear strength enhancement on delamination prediction

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    This study considers the intra-laminar damage mode in composite structures and its effect on delamination prediction. The progressive damage models for matrix cracking and fibre failure in ABAQUS, based on Hashin’s model, are only available for shell elements. The results presented here show that the predicted matrix cracking based on the damage model presently available in ABAQUS diverges from experimental results. A new model based on strain failure criteria, which can be used with both shell elements and 3D solid elements, has been developed. The effect of friction coefficient and enhancement factor on the delamination lobes within the delamination area was investigated, and it is shown that the intact zone can be captured in laminate [03/903]s and [903/03]s subjected to low-velocity impact, by using an enhancement factor of ¼ 0.75, and friction coefficient 0:5, together with the new model proposed here
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