Bandwidth Efficient Livestreaming in Mobile Wireless Networks: A Peer-to-Peer ACIDE Solution

In this paper, a media distribution model, Active Control in an Intelligent and Distributed Environment (ACIDE), and solutions are proposed for video and audio livestreaming in mobile wireless networks. A base station and a cluster formed by a number of users are the essential components. Inside a cluster, users can establish peer to peer communications. The users that are members of a cluster are considered peers. This paper addresses the problem of minimizing the bandwidth allocated to a cluster of n peers such that a continuous media play of all the peers is guaranteed. The basic idea is to send the livestream media in packages. A media package is divided into n blocks. The distribution of blocks to the peers of a cluster follows a two-phase, multi-step approach. In phase 1 each peer receives one block with the optimal size from the base station. In phase 2, peers exchange their media blocks simultaneously in a few steps. Then the media package can be reconstructed and a live media can be played continuously. Allocated bandwidth, the amount of bandwidth the base station has to allocate to this cluster in order to play live streaming media without interruptions, is a function of many parameters such as the block sizes, download and upload bandwidth values of peers. This problem is formulated as an optimization problem. A solution is proposed to find the optimal block sizes such that the allocated bandwidth is minimized. Both theoretical model and simulations show that when the number of peers is large, the optimal allocated bandwidth approaches the lower bound that is the bandwidth required for multicasting. In other words, the allocated bandwidth may be reduced n times.Comment: 8 pages, 6 figures, Conference Submissio

Time-Optimal and Conflict-Free Mappings of Uniform Dependence Algorithms into Lower Dimensional Processor Arrays

Most existing methods of mapping algorithms into processor arrays are restricted to the case where n-dimensional algorithms or algorithms with n nested loops are mapped into (n—l)-dimensional arrays. However, in practice, it is interesting to map n-dimensional algorithms into (k —l)-dimensional arrays where k\u3c.n. For example, many algorithms at bit-level are at least 4-dimensional (matrix multiplication, convolution, LU decomposition, etc.) and most existing bit level processor arrays are 2-dimensional. A computational conflict occurs if two or more computations of an algorithm are mapped into the same processor and the same execution time. In this paper, necessary and sufficient conditions are derived to identify all mappings without computational conflicts, based on the Hermite normal form of the mapping matrix. These conditions are used to propose methods of mapping any n-dimensional algorithm into (k— l)-dimensional arrays, kn—3, optimality of the mapping is guaranteed

Partitioning of Uniform Dependency Algorithms for Parallel Execution on MIMD/ Systolic Systems

An algorithm can be modeled as an index set and a set of dependence vectors. Each index vector in the index set indexes a computation of the algorithm. If the execution of a computation depends on the execution of another computation, then this dependency is represented as the difference between the index vectors of the computations. The dependence matrix corresponds to a matrix where each column is a dependence vector. An independent partition of the index set is such that there are no dependencies between computations that belong to different blocks of the partition. This report considers uniform dependence algorithms with any arbitrary kind of index set and proposes two very simple methods to find independent partitions of the index set. Each method has advantages over the other one for certain kind of application, and they both outperform previously proposed approaches in terms of computational complexity and/or optimality. Also, lower bounds and upper bounds of the cardinality of the maximal independent partitions are given. For some algorithms it is shown that the cardinality of the maximal partition is equal to the greatest common divisor of some subdeterminants of the dependence matrix. In an MIMD/multiple systolic array computation environment, if different blocks of ail independent partition are assigned to different processors/arrays, the communications between processors/arrays will be minimized to zero. This is significant because the communications usually dominate the overhead in MIMD machines. Some issues of mapping partitioned algorithms into MIMD/systolic systems are addressed. Based on the theory of partitioning, a new method is proposed to test if a system of linear Diophantine equations has integer solutions

A new Approach to Erdos Collaboration Network using PageRank

Using the data on Paul Erdos, his co-authors and their co-authors, we can construct a network called the Erd?s Collaboration network. Then we do reduction, analysis and visualization with it using program Pajek. In this paper, we develop a reasonable academic influence measuring method applying PageRank algorithm on the case of the Erd?s Collaboration network. We find that ALON, NOGA M is the most influential mathematician in the network. In addition, to measure impact, we construct a dynamic model, whereas it needs too much data for us to calculate the dynamic index. Keywords: PageRank, Collaboration network, Network analysis

Introducing a method for modeling knowledge bases in expert systems using the example of large software development projects

Goal of this paper is to develop a meta-model, which provides the basis for developing highly scalable artificial intelligence systems that should be able to make autonomously decisions based on different dynamic and specific influences. An artificial neural network builds the entry point for developing a multi-layered human readable model that serves as knowledge base and can be used for further investigations in deductive and inductive reasoning. A graph-theoretical consideration gives a detailed view into the model structure. In addition to it the model is introduced using the example of large software development projects. The integration of Constraints and Deductive Reasoning Element Pruning are illustrated, which are required for executing deductive reasoning efficiently

The First Release of the CSTAR Point Source Catalog from Dome A, Antarctica

In 2008 January the 24th Chinese expedition team successfully deployed the Chinese Small Telescope ARray (CSTAR) to DomeA, the highest point on the Antarctic plateau. CSTAR consists of four 14.5cm optical telescopes, each with a different filter (g, r, i and open) and has a 4.5degree x 4.5degree field of view (FOV). It operates robotically as part of the Plateau Observatory, PLATO, with each telescope taking an image every 30 seconds throughout the year whenever it is dark. During 2008, CSTAR #1 performed almost flawlessly, acquiring more than 0.3 million i-band images for a total integration time of 1728 hours during 158 days of observations. For each image taken under good sky conditions, more than 10,000 sources down to 16 mag could be detected. We performed aperture photometry on all the sources in the field to create the catalog described herein. Since CSTAR has a fixed pointing centered on the South Celestial Pole (Dec =-90 degree), all the sources within the FOV of CSTAR were monitored continuously for several months. The photometric catalog can be used for studying any variability in these sources, and for the discovery of transient sources such as supernovae, gamma-ray bursts and minor planets.Comment: 1 latex file and 9 figures The paper is accepted by PAS

The sky brightness and transparency in i-band at Dome A, Antarctica

The i-band observing conditions at Dome A on the Antarctic plateau have been investigated using data acquired during 2008 with the Chinese Small Telescope ARray. The sky brightness, variations in atmospheric transparency, cloud cover, and the presence of aurorae are obtained from these images. The median sky brightness of moonless clear nights is 20.5 mag arcsec^{-2} in the SDSS $i$ band at the South Celestial Pole (which includes a contribution of about 0.06 mag from diffuse Galactic light). The median over all Moon phases in the Antarctic winter is about 19.8 mag arcsec^{-2}. There were no thick clouds in 2008. We model contributions of the Sun and the Moon to the sky background to obtain the relationship between the sky brightness and transparency. Aurorae are identified by comparing the observed sky brightness to the sky brightness expected from this model. About 2% of the images are affected by relatively strong aurorae.Comment: There are 1 Latex file and 14 figures accepted by A

MiR-365-3p is a negative regulator in IL-17-mediated asthmatic inflammation

BackgroundInterleukin-17, the major proinflammatory cytokine secreted by Th17 cells, makes essential contribution to pathogenesis of severe asthma, while the detailed mechanisms, especially the involvement of microRNAs which are also important participants in asthma progression, remains largely unclear.MethodsIn this study, we established a house dust mite (HDM) extract-induced murine asthmatic models and the miRNA expression in the lung tissues of mice were profiled by miRNA microarray assay. The effect of miR-365-3p on IL-17-mediated inflammation was examined by qRT-PCR and immunoblotting analysis. The involvement of ARRB2 as target gene of miR-365-3p was verified by overexpression or RNA interference.ResultsHDM extract-induced asthmatic inflammation was proved to be IL17-mediated and miR-365-3p was screened out to be the only miRNA exclusively responsive to IL-17. miR-365-3p, whose expression was significantly downregulated upon IL-17 stimulation, was demonstrated to exert remarkable anti-inflammatory effect to decrease IL-17-provoked inflammatory cytokines (KC/IL-8 and IL-6) in both airway epithelial cells and macrophages of murine and human origins, verifying its universal antagonizing activity against IL-17-initiated inflammation across the two species. ARRB2 was characterized as the key target of miR-365-3p to negate IL-17-induced inflammatory cytokines.ConclusionTaken together, our data supported the notion that miR-365-3p, which was diminished by IL-17 in murine and human asthmatic pathogenesis, functioned as an essential negative mediator in IL-17-stimuated inflammatory response by targeting ARRB2, which would shed new light to the understanding and therapeutics thereof of asthmatic inflammation

Structural Constraints Identified with Covariation Analysis in Ribosomal RNA

Covariation analysis is used to identify those positions with similar patterns of sequence variation in an alignment of RNA sequences. These constraints on the evolution of two positions are usually associated with a base pair in a helix. While mutual information (MI) has been used to accurately predict an RNA secondary structure and a few of its tertiary interactions, early studies revealed that phylogenetic event counting methods are more sensitive and provide extra confidence in the prediction of base pairs. We developed a novel and powerful phylogenetic events counting method (PEC) for quantifying positional covariation with the Gutell lab’s new RNA Comparative Analysis Database (rCAD). The PEC and MI-based methods each identify unique base pairs, and jointly identify many other base pairs. In total, both methods in combination with an N-best and helix-extension strategy identify the maximal number of base pairs. While covariation methods have effectively and accurately predicted RNAs secondary structure, only a few tertiary structure base pairs have been identified. Analysis presented herein and at the Gutell lab’s Comparative RNA Web (CRW) Site reveal that the majority of these latter base pairs do not covary with one another. However, covariation analysis does reveal a weaker although significant covariation between sets of nucleotides that are in proximity in the three-dimensional RNA structure. This reveals that covariation analysis identifies other types of structural constraints beyond the two nucleotides that form a base pair