scholarly journals Probabilistic network sparsification with ego betweenness

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Amin Kaveh ◽  
Matteo Magnani ◽  
Christian Rohner
Keyword(s):  
High Density ◽  
Experimental Results ◽  
Topological Properties ◽  
Original Network ◽  
Probabilistic Networks ◽  
Probabilistic Network ◽  
Network Sparsification

AbstractSparsification is the process of decreasing the number of edges in a network while one or more topological properties are preserved. For probabilistic networks, sparsification has only been studied to preserve the expected degree of the nodes. In this work we introduce a sparsification method to preserve ego betweenness. Moreover, we study the effect of backboning and density on the resulting sparsified networks. Our experimental results show that the sparsification of high density networks can be used to efficiently and accurately estimate measures from the original network, with the choice of backboning algorithm only partially affecting the result.

Causal Probabilistic Network and Power Spectral Estimation Used in Sleep Stage Classification

1997 ◽  
Vol 36 (04/05) ◽  
pp. 41-46
Author(s):  
A. Kjaer ◽  
W. Jensen ◽  
T. Dyrby ◽  
L. Andreasen ◽  
J. Andersen ◽  
...  
Keyword(s):  
Sleep Stage ◽  
Spectral Estimation ◽  
Interrater Agreement ◽  
Probabilistic Networks ◽  
Probabilistic Network ◽  
Spectral Bands ◽  
Power Spectral ◽  
Stage Classification ◽  
Sleep Stage Classification ◽  
The Brain

Abstract.A new method for sleep-stage classification using a causal probabilistic network as automatic classifier has been implemented and validated. The system uses features from the primary sleep signals from the brain (EEG) and the eyes (AOG) as input. From the EEG, features are derived containing spectral information which is used to classify power in the classical spectral bands, sleep spindles and K-complexes. From AOG, information on rapid eye movements is derived. Features are extracted every 2 seconds. The CPN-based sleep classifier was implemented using the HUGIN system, an application tool to handle causal probabilistic networks. The results obtained using different training approaches show agreements ranging from 68.7 to 70.7% between the system and the two experts when a pooled agreement is computed over the six subjects. As a comparison, the interrater agreement between the two experts was found to be 71.4%, measured also over the six subjects.

scholarly journals STABILITY OF HIGH DENSITY CUBES IN RUBBLE MOUND BREAKWATERS

2020 ◽  
pp. 4
Author(s):  
Yalcin Yuksel ◽  
Marcel van Gent ◽  
Esin Cevik ◽  
H. Alper Kaya ◽  
Irem Gumuscu ◽  
...  
Keyword(s):  
Relative Density ◽  
Slope Angle ◽  
High Density ◽  
Experimental Results ◽  
Normal Density ◽  
Stability Number ◽  
Damage Initiation ◽  
Rubble Mound ◽  
The Stability ◽  
Rubble Mound Breakwaters

The stability number for rubble mound breakwaters is a function of several parameters and depends on unit shape, placing method, slope angle, relative density, etc. In this study two different densities for cubes in breakwater armour layers were tested to determine the influence of the density on the stability. The experimental results show that the stability of high density blocks were found to be more stable and the damage initiation for high density blocks started at higher stability numbers compared to normal density cubes.

scholarly journals Person Reidentification Model Based on Multiattention Modules and Multiscale Residuals

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Yongyi Li ◽  
Shiqi Wang ◽  
Shuang Dong ◽  
Xueling Lv ◽  
Changzhi Lv ◽  
...  
Keyword(s):  
Local Features ◽  
Attention Mechanism ◽  
Experimental Results ◽  
Original Network ◽  
Fine Grained ◽  
Backbone Network ◽  
Model Based ◽  
Local Branch ◽  
Feature Expression ◽  
Global And Local

At present, person reidentification based on attention mechanism has attracted many scholars’ interests. Although attention module can improve the representation ability and reidentification accuracy of Re-ID model to a certain extent, it depends on the coupling of attention module and original network. In this paper, a person reidentification model that combines multiple attentions and multiscale residuals is proposed. The model introduces combined attention fusion module and multiscale residual fusion module in the backbone network ResNet 50 to enhance the feature flow between residual blocks and better fuse multiscale features. Furthermore, a global branch and a local branch are designed and applied to enhance the channel aggregation and position perception ability of the network by utilizing the dual ensemble attention module, as along as the fine-grained feature expression is obtained by using multiproportion block and reorganization. Thus, the global and local features are enhanced. The experimental results on Market-1501 dataset and DukeMTMC-reID dataset show that the indexes of the presented model, especially Rank-1 accuracy, reach 96.20% and 89.59%, respectively, which can be considered as a progress in Re-ID.

Investigation of Graph-Based Detection in Iterative Decoding for Bit-Patterned Media Recording

2014 ◽  
Vol 979 ◽  
pp. 58-61
Author(s):  
Piya Kovintavewat
Keyword(s):  
Iterative Decoding ◽  
Intersymbol Interference ◽  
High Density ◽  
Soft Information ◽  
Experimental Results ◽  
Bit Patterned Media ◽  
Patterned Media ◽  
Recording Density ◽  
Moderate Complexity ◽  
Intertrack Interference

High-density bit-patterned media recording (BPMR) can be obtained by reducing the spacing between data bitislands in both the along-and across-track directions, thus leading to severe intersymbol interference (ISI) and intertrack interference (ITI) because of small bit and track pitches, respectively. Here, we propose to use the graph-based detector, instead of the trellis-based detector, in iterative decoding to combat the ISI and the ITI for a multi-head multi-track BPMR system. Specifically, the readback signal is sent to the graph-based detector before iteratively exchanging the soft information with a decoder. Experimental results indicate that at low to moderate complexity, the proposed scheme outperforms the existing schemes, especially at high recording density.

Natural Frequency Shift in a Centrifugal Compressor Impeller for High-Density Gas Applications

2011 ◽  
Author(s):  
Yohei Magara ◽  
Kazuyuki Yamaguchi ◽  
Haruo Miura ◽  
Naohiko Takahashi ◽  
Mitsuhiro Narita
Keyword(s):  
Centrifugal Compressor ◽  
Natural Frequencies ◽  
Mass Density ◽  
Mass Effect ◽  
Added Mass ◽  
High Density ◽  
Experimental Results ◽  
Centrifugal Compressors ◽  
Resonance Frequencies ◽  
Discharge Gas

In designing an impeller for centrifugal compressors, it is important to predict the natural frequencies accurately in order to avoid resonance caused by pressure fluctuations due to rotorstator interaction. However, the natural frequencies of an impeller change under high-density fluid conditions. The natural frequencies of pump impellers are lower in water than in air because of the added mass effect of water, and in high-pressure compressors the mass density of the discharge gas can be about one-third that of water. So to predict the natural frequencies of centrifugal compressor impellers, the influence of the gas must be considered. We previously found in the non-rotating case that some natural frequencies of an impeller decreased under high-density gas conditions but others increased and that the increase of natural frequencies is caused by fluid-structure interaction, not only the added mass effect but also effect of the stiffness of the gas. In order to develop a method for predicting natural frequencies of centrifugal compressor impellers for high-density gas applications, this paper presents experimental results obtained using a variable-speed centrifugal compressor with vaned diffusers. The maximum mass density of its discharge gas is approximately 300 kg/m3. The vibration stress on an impeller when the compressor was speeding up or slowing down was measured by strain gages, and the natural frequencies were determined by resonance frequencies. The results indicate that for high-density centrifugal compressors, some natural frequencies of an impeller increased in high-density gas. To predict this behavior, we developed a calculation method based on the theoretical analysis of a rotating disc. Its predictions are in good agreement with experimental results.

Effect of Electrical Pulse Ageing on Microstructure and Properties of Cu-2.5Fe-0.03P-0.1Zn Copper Alloy

2005 ◽  
Vol 475-479 ◽  
pp. 2635-2638
Author(s):  
Jin Liang Huang ◽  
Qiang Li ◽  
Ping Liu ◽  
Qi Ming Dong
Keyword(s):  
Electrical Conductivity ◽  
Theoretical Analysis ◽  
Copper Alloy ◽  
High Density ◽  
Experimental Results ◽  
Electrical Pulse ◽  
Lead Frame ◽  
Microstructure And Properties ◽  
Nano Size ◽  
The Ideal

Milisecond high density electrical pulse was used to age one of the typical IC lead frame materials Cu-2.5Fe-0.03P-0.1Zn copper alloy. The effects of electrical pulse aging on the microstructures, electrical conductivity and microhardness of this alloy were systematically investigated. The experimental results shown that the alloy phase precipitated in Cu-2.5Fe-0.03P-0.1Zn copper alloy during electrical pulse aging could be controlled to the order of nano-size and the ideal match of electrical conductivity and microhardness could be achieved in the condition of optimized parameters of electrical pulse. The electrical conductivity of the alloy was kept at above 60%IACS while the microhardness reached to HV115. A preliminary theoretical analysis was made to explain the unique action of electrical pulse.

Natural Frequency Shift in a Centrifugal Compressor Impeller for High-Density Gas Applications

2012 ◽  
Vol 135 (1) ◽  
Author(s):  
Yohei Magara ◽  
Kazuyuki Yamaguchi ◽  
Haruo Miura ◽  
Naohiko Takahashi ◽  
Mitsuhiro Narita
Keyword(s):  
Centrifugal Compressor ◽  
Natural Frequencies ◽  
Mass Density ◽  
Mass Effect ◽  
Added Mass ◽  
High Density ◽  
Experimental Results ◽  
Centrifugal Compressors ◽  
Resonance Frequencies ◽  
Discharge Gas

In designing an impeller for centrifugal compressors, it is important to predict the natural frequencies accurately in order to avoid resonance caused by pressure fluctuations due to rotor-stator interaction. However, the natural frequencies of an impeller change under high-density fluid conditions. The natural frequencies of pump impellers are lower in water than in air because of the added mass effect of water, and in high-pressure compressors the mass density of the discharge gas can be about one-third that of water. So to predict the natural frequencies of centrifugal compressor impellers, the influence of the gas must be considered. We previously found in the nonrotating case that some natural frequencies of an impeller decreased under high-density gas conditions but others increased and that the increase of natural frequencies is caused by fluid-structure interaction, not only the added mass effect but also effect of the stiffness of the gas. In order to develop a method for predicting natural frequencies of centrifugal compressor impellers for high-density gas applications, this paper presents experimental results obtained using a variable-speed centrifugal compressor with vaned diffusers. The maximum mass density of its discharge gas is approximately 300 kg/m3. The vibration stress on an impeller when the compressor was speeding up or slowing down was measured by strain gauges, and the natural frequencies were determined by resonance frequencies. The results indicate that for high-density centrifugal compressors, some natural frequencies of an impeller increased in high-density gas. To predict this behavior, we developed a calculation method based on the theoretical analysis of a rotating disk. Its predictions are in good agreement with experimental results.

A SELF-RECTIFYING BIPOLAR RRAM DEVICE BASED ON Ni/HfO2/n+-Si STRUCTURE

2014 ◽  
Vol 28 (04) ◽  
pp. 1450030
Author(s):  
YINGTAO LI ◽  
XINYU JIANG ◽  
CHUNLAN TAO
Keyword(s):  
Resistive Switching ◽  
High Density ◽  
Point Of View ◽  
The Self ◽  
Experimental Results ◽  
Schottky Junction ◽  
Conductive Filament ◽  
Switching Mechanism ◽  
Switching Characteristics

A bipolar RRAM device based on Ni / HfO 2/n+- Si structure with self-rectifying characteristics is demonstrated for high density cross-bar memory application. Experimental results indicate that Ni conductive filament generated at LRS plays an important role in resistive switching, resulting in the formation of a Schottky junction at the Ni -CF/n+- Si interface which determines the self-rectifying behavior at LRS. These results are very important from the point of view of understanding the self-rectifying switching mechanism and improving the resistive switching characteristics of self-rectifying RRAM devices.

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