In this study, the authors demonstrate the potential of hard-decision algorithm in industrial 5G NR channel coding. This study aims to show different forward error correction algorithms that can be expected in the con...
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In this study, the authors demonstrate the potential of hard-decision algorithm in industrial 5G NR channel coding. This study aims to show different forward error correction algorithms that can be expected in the context of cloud radio access network. Based on low density parity check (LDPC) min-sum (ms) algorithm, an improved hard-decision algorithm is proposed. The decoding process and performances are shown and compared with ms algorithm. To identify the advantage of this proposal, a test bench is launched in Cisco server using X86 chipset. Its results show a good trade-off between latency and performance.
Aiming at the problems of over stacking, warping deformation and rapid adjustment of layer thickness in electron beam additive manufacturing, the 3D printing slicing algorithm and partition scanning strategy for numer...
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Aiming at the problems of over stacking, warping deformation and rapid adjustment of layer thickness in electron beam additive manufacturing, the 3D printing slicing algorithm and partition scanning strategy for numerical control systems are studied. The GPU (graphics processing unit) is used to slice the 3D model, and the STL (stereolithography) file is calculated in parallel according to the normal vector and the vertex coordinates. The voxel information of the specified layer is dynamically obtained by adjusting the projection matrix to the slice height. The ms (marching squares) algorithm is used to extract the coordinate sequence of the binary image, and the ordered contour coordinates are output. In order to avoid shaking of the electron gun when the numerical control system is forming the microsegment straight line, and reduce metal overcrowding in the continuous curve C-0, the NURBS (non-uniform rational b-splines) basis function is used to perform curve interpolation on the contour data. Aiming at the deformation problem of large block components in the forming process, a hexagonal partition and parallel line variable angle scanning technology is adopted, and an effective temperature and deformation control strategy is formed according to the European-distance planning scan order of each partition. The results show that the NURBS segmentation fits closer to the original polysurface cut line, and the error is reduced by 34.2% compared with the STL file slice data. As the number of triangular patches increases, the algorithm exhibits higher efficiency, STL files with 1,483,132 facets can be cut into 4488 layers in 89 s. The slicing algorithm involved in this research can be used as a general data processing algorithm for additive manufacturing technology to reduce the waiting time of the contour extraction process. Combined with the partition strategy, it can provide new ideas for the dynamic adjustment of layer thickness and deformation control in the formin
The advancements in multimedia watermarking technologies have gained lots of attention in the past few years. A digital video watermarking is the data embedded in the video and sent to the recipient. Privacy is consid...
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The advancements in multimedia watermarking technologies have gained lots of attention in the past few years. A digital video watermarking is the data embedded in the video and sent to the recipient. Privacy is considered as the major issue in digital media while hiding the data by maintaining the video quality. This paper presents an optimization algorithm for video watermarking based on interesting regions. Here, the optimal regions for the video watermarking are selected using the proposed Chronological-Moth Search (Chronological-ms) approach, which is established by modifying the Moth Search (ms) algorithm using chronological concept. The employed fitness function contains cost function, which uses several parameters, like energy, edge, pixel intensity, brightness, and coverage. At first, the input video file is subjected to feature extraction, and the extracted features are employed for selecting the optimal regions using the proposed Chronological-ms. After that, the wavelet transform is given to the original image to obtain the wavelet coefficients. Here, the privacy message is divided into binary images using bit plane technique. Thus, the embedding process is carried out for hiding the secret message with the use of interesting regions identified using the proposed Chronological-ms algorithm and is retrieved at the extraction phase. The performance of the proposed Chronological-ms shows superior performance with correlation coefficient and PSNR of 1.00 and 98.741 dB, respectively. (C) 2019 Elsevier Ltd. All rights reserved.
The development mechanisms of an explosive cyclone over Central Mediterranean are examined, by relating the cloud patterns in the infrared, water vapour and visible channels of the Meteosat Second Generation (msG) sat...
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ISBN:
(纸本)9780819496386
The development mechanisms of an explosive cyclone over Central Mediterranean are examined, by relating the cloud patterns in the infrared, water vapour and visible channels of the Meteosat Second Generation (msG) satellite images, to the surface-upper air operational analyses and thermodynamic parameters, including potential and geostrophic vorticity analyses, potential and equivalent potential temperature, static stability and thermal heat fluxes. The specific case study derived from an updated climatology of Mediterranean explosive cyclones for the 2002-2010 period, being performed with the aid of the University of Melbourne Cyclone Tracking scheme (ms algorithm) and ERA-INTERIM datasets. It was found that during the ordinary cyclogenesis the increased mid-upper level relative humidity over Northern Algeria along with the enhanced moisture gradient in the area between Portugal and Spain;indicate the existence of a jet -streak, with the dry zone to be located on the cold side of the jet axis. The descent of the dry air is more pronounced within the left exit region of the jet streak in the poleward portion of an upper confluence zone. Six hours later, the eastward movement of the cloud pattern in the Northern African coasts significantly resembles the structure of a baroclinic leaf, being related to the early stages of surface frontogenesis, due to the deformation process within a strong wind field. During the time of rapid deepening, when the surface cyclone propagated from the Northern African coasts towards the area of Sicily - Gulf of Taranto, the development is characterised by the transition from the baroclinic leaf structure to the comma cloud one and finally the formation of a bent-back occlusion.
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