Self-configuring virtual networks rely on structured P2P routing to provide seamless connectivity among nodes through overlay routing of virtual IP packets, support decentralized hole-punching to establish bi-directio...
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ISBN:
(纸本)9781595939975
Self-configuring virtual networks rely on structured P2P routing to provide seamless connectivity among nodes through overlay routing of virtual IP packets, support decentralized hole-punching to establish bi-directional communication links among nodes behind network address translators, and dynamic configuration of virtual IP addresses. Our experiences with deployments of virtual networks in support of wide-area overlays of virtual workstations (WOWs) reveal that connectivity constraints imposed by symmetric NATs and by Internet route outages often hinder P2P overlay structure maintenance and routability, subsequently limiting the ability of WOWs to deliver high-throughput computing through aggregation of resources in different domains. In this paper, we describe and evaluate two novel approaches which are generally applicable and fully decentralized, and show that they improve routability of structured P2P networks in such connectivity constrained environments: (1) a fault-tolerant routing algorithm based on simulated annealing from optimization theory, and (2) tunneling of connections between adjacent nodes (in the P2P identifier space) over common neighbors when direct communication is not possible. Simulation-based analyses show that when pairs of nodes only have 70% chance of being able to communicate directly, the described approaches improve all-to-all routability of the network horn 90% to 99%. We have implemented these techniques in the IP-over-P2P (IPOP) virtual network and have conducted experiments with a 80-node WOW Condor pool, demonstrating that, at 81% probability of establishing a pair-wise connection, annealing and tunneling combined allow all nodes to be connected to the pool, compared to only 160 nodes in the absence of these techniques. Copyright 2008 ACM.
In this paper, we propose a spatial temporal video-text detection technique which proceed in two principal steps: potential text region detection and a filtering process. In the first step we divide dynamically each p...
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In this paper, we propose a spatial temporal video-text detection technique which proceed in two principal steps: potential text region detection and a filtering process. In the first step we divide dynamically each pair of consecutive video frames into sub block in order to detect change. A significant difference between homologous blocks implies the appearance of an important object which may be a text region. The temporal redundancy is then used to filter these regions and forms an effective text region. The experimentation driven on a variety of video sequences shows the effectiveness of our approach by obtaining a 89,39% as precision rate and 90,19 as recall.
For Internet forum Points of Interest(PoI),existing analysis methods are usually lack of usability analysis under different conditions and ignore the long-term variation,which lead to blindness in method *** address t...
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For Internet forum Points of Interest(PoI),existing analysis methods are usually lack of usability analysis under different conditions and ignore the long-term variation,which lead to blindness in method *** address this problem,this paper proposed a PoI variation prediction framework based on similarity analysis between long and short *** on the framework,this paper presented 5 PoI analysis algorithms which can be categorized into 2 types,i.e.,the traditional sequence analysis methods such as autoregressive integrated moving average model(ARIMA),support vector regressor(SVR),and the deep learning methods such as convolutional neural network(CNN),long-short term memory network(LSTM),Transformer(TRM).Specifically,this paper firstly divides observed data into long and short windows,and extracts key words as PoI of each ***,the PoI similarities between long and short windows are calculated for training and ***,series of experiments is conducted based on real Internet forum *** results show that,all the 5 algorithms could predict PoI variations well,which indicate effectiveness of the proposed *** the length of long window is small,traditional methods perform better,and SVR is the *** the contrary,the deep learning methods show superiority,and LSTM performs *** results could provide beneficial references for PoI variation analysis and prediction algorithms selection under different parameter configurations.
Today's mobile devices or smartphones have a revolutionary impact on how we communicate, especially after the advent of devices like smart watches and Google glasses that require new ways to interact with them. To...
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In this article, we investigate the use of joint a-entropy for 3D ear matching by incorporating the local shape feature of 3D ears into the joint a-entropy. First, we extract a sut^cient number of key points from the ...
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In this article, we investigate the use of joint a-entropy for 3D ear matching by incorporating the local shape feature of 3D ears into the joint a-entropy. First, we extract a sut^cient number of key points from the 3D ear point cloud, and fit the neighborhood of each key point to a single-value quadric surface on product parameter regions. Second, we define the local shape feature vector of each key point as the sampling depth set on the parametric node of the quadric surface. Third, for every pair of gallery ear and probe ear, we construct the minimum spanning tree (MST) on their matched key points. Finally, we minimize the total edge weight of MST to estimate its joint a-entropy the smaller the entropy is, the more similar the ear pair is. We present several examples to demonstrate the advantages of our algorithm, including low time complexity, high recognition rate, and high robustness. To the best of our knowledge, it is the first time that, in computer graphics, the classical information theory of joint a-entropy is used to deal with 3D ear shape recognition.
In this paper, we demonstrate six types of metamaterial absorbers (MMAs) by measuring their absorptivities in an X-band (8 12 GHz) rectangular waveguide. Some of the MMAs have been demonstrated previously by using...
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In this paper, we demonstrate six types of metamaterial absorbers (MMAs) by measuring their absorptivities in an X-band (8 12 GHz) rectangular waveguide. Some of the MMAs have been demonstrated previously by using the free space measurement method, and the others are proposed firstly in this paper. The measured results show that all of the six MMAs exhibit high absorptivities above 98%, which have similar absorbing characteristics to those measured in the free space. The numerically obtained surface current densities for each MMA show that the absorbing mechanism is the same as that under the free space conditions. Such a demonstration method is superior to the conventional free space measurement method due to the small-scale test samples required, the simple measure device, and its low cost. Most importantly, the proposed method opens a way to enable MMAs to be used in microwave applications such as matched terminations.
In this paper, we present a new variant to show results of information retrieval process. Search results proposed here are in the form of textual abstract instead of returning a list of links pointing to relevant web ...
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In this paper, we present a new variant to show results of information retrieval process. Search results proposed here are in the form of textual abstract instead of returning a list of links pointing to relevant web documents. Our current work materializes collaboration between two independent axes: Semantic Web and Fuzzy Logic. The automatic abstract generation represents an extension of our previous works aimed to create an information retrieval system dedicated for kids.
With the spread of online social media websites, a huge amount of online content is continuously provided. However, some contents gain an important attention from users while other contents are completely ignored. Thi...
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In this paper, we propose a pseudo-relevance feedback approach based on linear operators: vector space basis change and cross product. The aim of pseudo-relevance feedback methods based on vector space basis change IB...
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Motivated by humans' ability to lipread, the visual component is considered to yield information in the speech recognition system. The lip-reading is the perception of the speech purely based on observing the talk...
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Motivated by humans' ability to lipread, the visual component is considered to yield information in the speech recognition system. The lip-reading is the perception of the speech purely based on observing the talker lip movements. The major difficulty of the lip- reading system is the extraction of the visual speech descriptors. In fact, to ensure this task it is necessary to carry out an automatic localization and tracking of the labial gestures. We present in this paper a new automatic approach for lip and point of interest localization on a speaker's face based both on the color information of mouth and a geometric model of lips. This hybrid solution makes our method more tolerant to noise and artifacts in the image. Experiments revealed that our lip POI localization approach for lip-reading purpose is promising. The presented results show that our system recognizes 94.64 % of French visemes.
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