ppxscal/embedding_network huggingface dataset:
RADOS: a scalable, reliable storage service for petabyte-scale storage clusters
Authors: Sage A. Weil, Andrew W. Leung, Scott A. Brandt, Carlos Maltzahn
Venue: Proceedings of the 2nd international workshop on Petascale data storage: held in conjunction with Supercomputing '07 (2007)

Brick and object-based storage architectures have emerged as a means of improving the scalability of storage clusters. However, existing systems continue to treat storage nodes as passive devices, despite their ability to exhibit significant intelligence and autonomy. We present the design and implementation of RADOS, a reliable object storage service that can scales to many thousands of devices by leveraging the intelligence present in individual storage nodes. RADOS preserves consistent data access and strong safety semantics while allowing nodes to act semi-autonomously to self-manage replication, failure detection, and failure recovery through the use of a small cluster map. Our implementation offers excellent performance, reliability, and scalability while providing clients with the illusion of a single logical object store.
Fully dynamic biconnectivity in graphs
Authors: M. Rauch
Venue: Proceedings of the 33rd Annual Symposium on Foundations of Computer Science (1992)

The author presents an algorithm for maintaining the bi-connected components of a graph during a sequence of edge insertions and deletions. It requires linear storage and preprocessing time. The amortized running time for insertions and for deletions is O(m/sup 2/3/), where m is the number of edges in the graph. Each query of the form 'Are the vertices u and v biconnected?' can be answered in time O(1). This is the first sublinear algorithm for this problem. If the input is a planar embedded graph, the amortized running time for insertions and deletions drops to O( square root nlogn) and the worst case query time is O((logn)/sup 2/), where n is the number of vertices in the graph. The best previously known solution takes time O(n/sup 2/3/) per update or query.
Project-oriented resource assignment: from business process modelling to business process instantiation with operational performance consideration
Authors: Y. Zhou, Y. Chen
Venue: International Journal of Computer Integrated Manufacturing (2008)

Business process modelling is the description of business process chains and their associated aspects such as resources, information, organization and so on. Business process instantiation is the operational process-centred performance configuration through project-oriented task decomposition, resource assignment and activity arrangement. The present paper elucidates the links between business process modelling and project-oriented business process instantiation, and proposes the optimization model and algorithm of resource assignment of business processes in multi-project environment. Based on the extended AON (activity on node) graph, the trade-off analytical model between time and cost is developed considering resources, cost and time constraints as well as decision nodes such as OR and XOR (exclusively OR) besides AND junction in IDEF3 process models for multi-project resource assignment. The proposed algorithm employs genetic algorithm to deal with resource assignment and stack technique and unified time window to tackle resource constraints and decision nodes. The validity of the model and the effectiveness of the algorithm are revealed. The proposed methodology, model and algorithm of project-oriented resource assignment from business process modelling to business process instantiation are a useful support for the establishment of truly integrated enterprise modelling and analysis environment.
Trade-off scheme for fault tolerant connected dominating sets on size and diameter
Authors: Ning Zhang, Incheol Shin, Feng Zou, Weili Wu, My Tra Thai
Venue: Proceeding of the 1st ACM international workshop on Foundations of wireless ad hoc and sensor networking and computing (2008)

Connected Dominating Set (CDS) has been a well known approach for constructing a virtual backbone to alleviate the broadcasting storm in wireless networks. Current research has focused on minimizing the size and diameter or improving the fault tolerance of CDS. However, to our best knowledge, no existing research has considered these three important factors together in a single model. In this paper, we introduce the fault tolerant model studying a joint optimization problem in which the objective is to minimize the CDS size as well as the network latency. This model also addresses the tradeoffs between the objective functions. We next propose one approximation algorithm and two distributed algorithms with constant ratios for the model. Simulation results show that our algorithms can gain good tradeoffs between the three factors, which coincide with theoretical analysis. Moreover, our algorithms could obtain a better performance than previous work.
A fast joining operation for highly dynamic chord system
Authors: Xiao-Jin Ren, Guo-An Wang, Zhi-Min Gu, Zhi-Wei Gao
Venue: Proceedings of the 13th International Conference on Parallel and Distributed Systems - Volume 02 (2007)

Highly dynamic characteristic is one of the most important characteristics of P2P system in nature. Nodes may join in or leave the P2P system at any moment. Frequently joining or leaving must increase the maintenance overhead greatly in DHT system. To decrease the cost, we introduce a new join operation for Chord, named F-Join that is suitable for highly dynamic environments and can fast join in the system. F-Join builds finger table of node by the support of the fingers of the node&#x2019;s successor and predecessor. So, it decreases the lookup cost of building node&#x2019;s finger table and decreases the maintenance overheads finally. The theory and simulations show that F-Join can decrease the maintenance overheads greatly and improve the lookup performance.
Fault-tolerant wait-free shared objects
Authors: P. Jayanti, T. D. Chandra, S. Toueg
Venue: Proceedings of the 33rd Annual Symposium on Foundations of Computer Science (1992)

The authors classify object failures into two broad categories: responsive and non-responsive. They require that wait-free objects subject to responsive failures continue to respond (in finite time) to operation invocations. The responses may be incorrect. In contrast, wait-free objects subject to non-responsive failures are exempt from responding to operation invocations. Such objects may 'hang' on the invoking process. They divide responsive failures into three models: R-crash,R-omission, and R-arbitrary. They divide non-responsive failures into crash, omission, and arbitrary. An object subject to crash failure behaves correctly until it fails, and once it fails, it never responds to operation invocations. An object subject to omission failures may fail to respond to the invocations of an arbitrary subset of processes, but continue to respond to the invocations of the remaining processes (forever).
Interconnect Signaling and Layout Optimization to Manage Thermal Effects Due to Self Heating in On-Chip Signal Buses
Authors: Krishnan Sundaresan, Nihar R. Mahapatra
Venue: Proceedings of the 9th international symposium on Quality Electronic Design (2008)

Power dissipation in long interconnects and increasing wire temperatures due to (self) Joule heating are becoming important issues to address in nanometer-scale technologies. While many low-power bus encoding schemes have been proposed, no encoding techniques exist for explicitly reducing temperatures in high-speed on-chip signal buses. In this work, we propose: (1) an interconnect/wire signaling and layout optimization that considers self and inter-wire coupling activities and is tailored to data traffic characteristics; (2) an integer linear programming (ILP)technique to optimize bus energy and; (3) a novel methodology to add thermal constraints to this ILP optimization to reduce not only average but also peak wire temperatures. Our contributions enable a designer toefficiently explore the hottest wire temperature and total bus dynamic energy trade-off space. One such trade-off point yielded a thermally-constrained, energy-optimal encoding scheme that reduced wire temperatures by up to 12.26C (12.96C) for data(instruction) buses and significant average energy savings of 14.24% (16.17%) for data(instruction) bus. These results are still much better than energy reductions obtained by previous work.
The influence of 1nm AlN interlayer on properties of the Al0.3Ga0.7N/AlN/GaN HEMT structure
Authors: Lunchun Guo, Xiaoliang Wang, Cuimei Wang, Hongling Xiao, Junxue Ran, Weijun Luo, Xiaoyan Wang, Baozhu Wang, Cebao Fang, Guoxin Hu
Venue: Microelectronics Journal (2008)

The sheet carrier concentrations, conduction band profiles and amount of free carriers in the barriers have been determined by solving coupled Schrodinger and Poisson equation self-consistently for coherently grown Al"0"."3Ga"0"."7N/GaN and Al"0"."3Ga"0"."7N/AlN/GaN structures on thick GaN. The Al"0"."3Ga"0"."7N/GaN heterojunction structures with and without 1nm AlN interlayer have been grown by MOCVD on sapphire substrate, the physical properties for these two structures have been investigated by various instruments such as Hall measurement and X-ray diffraction. By comparison of the theoretical and experimental results, we demonstrate that the sheet carrier concentration and the electrons mobility would be improved by the introduction of an AlN interlayer for Al"0"."3Ga"0"."7N/GaN structure. Mechanisms for the increasing of the sheet carrier concentration and the electrons mobility will be discussed in this paper.
Lower bounds on the competitive ratio for mobile user tracking and distributed job scheduling
Authors: N. Alon
Venue: Proceedings of the 33rd Annual Symposium on Foundations of Computer Science (1992)

The authors prove a lower bound of Omega (log n/log log n) on the competitive ratio of any (deterministic or randomised) distributed algorithm for solving the mobile user problem on certain networks of n processors. The lower bound holds for various networks, including the hypercube, any network with sufficiently large girth, and any highly expanding graph. A similar Omega (log n/log log n) lower bound is proved for the competitive ratio of the maximum job delay of any distributed algorithm for solving a distributed scheduling problem on any of these networks. The proofs combine combinatorial techniques with tools from linear algebra and harmonic analysis and apply, in particular, a generalization of the vertex isoperimetric problem on the hypercube, which may be of independent interest.
An IMS Control and Access Layer PR-SCTP Based Network
Authors: E. Lopes Filho, G. T. Hashimoto, P. F. Rosa
Venue: Proceedings of the Fourth International Conference on Networking and Services (2008)

The recent growth of peer-to-peer traffic and the popularity of streaming video is a cause for possible instability of the networks because most of these services run over UDP, without any mechanism for congestion control. Moreover, the adaptive features of peer-to-peer traffic may lead a misuse of the classical QoS rules legitimately applied to end-user applications. This paper proposes the usage of the Partial Reliability extension of the Stream Control Transmission Protocol (PR-SCTP) as the unique transport entity in an IP Multimedia Subsystem (IMS) network control and access layer, to mitigate situations of traffic congestion. The IMS is a 3GPP standardized approach that enables convergence of data, voice, video and mobile network technology over an IP-based network. Session Initiation Protocol (SIP) and Session Description Protocol (SDP) are the groundwork to support the convergence proposed by IMS. PR-SCTP provides several features to improve the transport of SIP between the IMS entities and after introducing the motivation to this proposal, we discuss and compare the benefits and drawbacks of using PR-SCTP instead of TCP or UDP to transport SIP.
Five Simple Steps to Improve Your Website's Search Engine Ranking
Authors: P.,  Bensky
Venue:  (2007)

Over the past few years, search engine optimization has developed into something of a science as webmasters and business owners try to figure out how to trick the internet search engines into listing THEIR sites near the top of the search results list. A number of big, pricey books have been written on the subject. But it really is not that complicated! We've boiled it down to FIVE SIMPLE STEPS that just about anybody can follow. It's so simple that this book is fewer than 50 pages long! You won't get bogged down with boring, technical descriptions and geek-speak; this book is written in easy-to-read plain English, with plenty of examples and clear descriptions of technical terms where they are absolutely necessary. "But I'm not a web designer!" You don't need to be. You just need to be able to create simple web pages. "I don't have a budget for paid ads!" This book is not about paying for "sponsored links", adwords, or any other kind of paid advertising. The technique we describe will cost you nothing other than the price of this book and some of your time.
Rate Bounds on SSIM Index of Quantized Image DCT Coefficients
Authors: Sumohana S. Channappayya, Alan C. Bovik, Robert W. Heath Jr., Constantine Caramanis
Venue: Proceedings of the Data Compression Conference (2008)

In this paper, we derive bounds on the Structural SIMilarity (SSIM) Index as a function of quantization rate for fixed-rate uniform quantization of image discrete cosine transform (DCT) coefficients under thehigh rate assumption. The space domain SSIM Index is first expressed in terms of the DCT coefficients of the space domain vectors. The transform domain SSIM Index is then used to derive bounds on the average SSIM Index as a function of quantization rate for Gaussian and Laplacian sources. As an illustrative example, uniform quantization of the DCT coefficients of natural images is considered. We show that the SSIM Index between the reference and quantized images fall within the bounds for a large set of natural images. Further, we show using a simple example that the proposed bounds could be very useful for rate allocation problems in practical image and video coding applications.
HT-RLS: High-Throughput Web Tool for Analysis of DNA Microarray Data Using RLS classifiers
Authors: P. D'Onorio De Meo, D. Carrabino, M. D'Antonio, A. D'Addabbo, S. Liuni, F. Mignone, G. Pesole, N. Ancona
Venue: Proceedings of the 2008 Eighth IEEE International Symposium on Cluster Computing and the Grid (2008)

Gene expression from DNA microarray data offers biologists and pathologists the possibility to deal with the problem of disease (e.g. cancer) diagnosis and prognosis from a quantitative point of view. Microarray data provide a snapshot of the molecular status of a sample of cells in a given tissue, returning the expression levels of thousands of genes simultaneously. Several mathematical methods from learning theory, such as Regularized Least Squares (RLS) classifiers or Support Vector Machines (SVM), have been extensively adopted to classify gene expression data. These methods can be useful to answer some relevant questions such as 1) what is the right amount of data to build an accurate classifier? 2) How many and which genes are correlated with a specific pathology? The computational analysis to statistically estimate the accuracy of the chosen models is particularly time consuming, burning several days of CPU time and without high-throughput or high-performance tools becomes practically unfeasible to obtain results in a reasonable time for biomedical community. We have implemented an independent, flexible and scalable platform, for a high-throughput large-scale microarray gene expression data analysis and classification, based on R tool for statistical computing. It integrates databases and computational intensive algorithms, based on RLS classifiers and a powerful web client for data training and graphical visualization of predicted results. Our platform provides statistically significant answers to the study of the gene expression by means of microarray data and supplying useful information to relevant questions in the diagnosis and prognosis of diseases in a reasonable time. The web resource is available free of charge for academic and non-profit institutions.
Noise Generator with DSP96002
Authors: Zdenek Dokoupil, Karel Bartusek, Eva Gescheidtova
Venue: Proceedings of the Third International Conference on Systems (2008)

When measuring the transfer and properties of many electronic circuits it is necessary to use a measuring signal with noise of defined properties. In the paper, the design and software implementation are described of a generator of pseudorandom binary noise signal of adjustable length and with repetition of pseudorandom binary signal sequence. The parameters of noise outputs are stable, well defined and variable over a wide range. The Noise Generator described in this paper is a very simplified and software-emulated version of the HP 722A Noise Generator produced by Hewlett-Packard [1].
On the properties of spam-advertised URL addresses
Authors: Eleni Georgiou, Marios D. Dikaiakos, Athena Stassopoulou
Venue: Journal of Network and Computer Applications (2008)

The main purpose of most spam e-mail messages distributed on Internet today is to entice recipients into visiting World Wide Web pages that are advertised through spam. In essence, e-mail spamming is a campaign that advertises URL addresses at a massive scale and at minimum cost for the advertisers and those advertised. Nevertheless, the characteristics of URL addresses and of web sites advertised through spam have not been studied extensively. In this paper, we investigate the properties of URL-dissemination through spam e-mail, and the characteristics of URL addresses disseminated through spam. We conclude that spammers advertise URL addresses non-repetitively and that spam-advertised URLs are short-lived, elusive, and therefore hard to detect and filter. We also observe that reputable URL addresses are sometimes used as decoys against e-mail users and spam filters. These observations can be valuable for the configuration of spam filters and in order to drive the development of new techniques to fight spam.
FBBM: A New Backup Method with Data De-duplication Capability
Authors: Tianming Yang, Dan Feng, Jingning Liu, Yaping Wan
Venue: Proceedings of the 2008 International Conference on Multimedia and Ubiquitous Engineering (2008)

Data de-duplication eliminates multiple copies of the same file and repeated chunks or segments of data within those files, thus reduces disk capacity and bandwidth required for backups. Recently, driven by the needs of large-capacity/high performance data backup, data de-duplication is becoming a new research focus of the storage industry. In this paper, we present a fingerprint-based backup method named FBBM which performs data de-duplication in the backup. FBBM breaks files into variable sized chunks using anchor-based chunking scheme for the purpose of duplication detection. Chunks are stored on a write-once RAID (Redundant Array of Inexpensive Disks) and indexed and addressed by the hash of their content, this leads to intrinsically single instance storage. FBBM outperforms traditional backup methods in terms of storage and bandwidth saving. This makes it a promising tool for modern enterprises to backup or archive their ever-growing valuable data with low storage and bandwidth cost.
An efficient algorithm for mining frequent closed itemsets in dynamic transaction databases
Authors: Ruili Wang, Luofeng Xu, Stephen Marsland, Ramesh Rayudu
Venue: International Journal of Intelligent Systems Technologies and Applications (2008)

In this paper we propose an extension algorithm to CLOSET+, one of the most efficient algorithms for mining frequent closed itemsets in static transaction databases, to allow it to mine frequent closed itemsets in dynamic transaction databases. In a dynamic transaction database, transactions may be added, deleted and modified with time. Based on two variant tree structures, our algorithm retains the previous mined frequent closed itemsets and updates them by considering the changes in the transaction databases only. Hence, the frequent closed itemsets in the current transaction database can be obtained without rescanning the entire changed transaction database. The performance of the proposed algorithm is compared with CLOSET+, showing performance improvements for dynamic transaction databases compared to using mining algorithms designed for static transaction databases.
Simulation of clinical electrophysiology in 3D human atria: a high-performance computing and high-performance visualization application
Authors: Sanjay Kharche, Gunnar Seemann, Lee Margetts, Joanna Leng, Arun V. Holden, Henggui Zhang
Venue: Concurrency and Computation: Practice Experience (2008)

Atrial fibrillation (AF) is a common cardiac disease of genuine clinical concern with high rates of morbidity, leading to major personal and National Health Service costs. Computer modelling of AF using biophysically detailed cellular models with realistic 3D anatomical geometry allows investigation of the underlying ionic mechanisms in far more detail than with experimental physiology. We have developed a 3D virtual human atrium that combines detailed cellular electrophysiology including ion channel kinetics and homeostasis of ionic concentrations with anatomical details. The segmented anatomical structure and the multivariable nature of the system make the 3D simulations of AF computationally large and intensive. Computational demands are such that a full problem-solving environment requires access to resources of high-performance computing (HPC), high-performance visualization (HPV), remote data repositories and backend infrastructure. This is a classic example of eScience and Grid-enabled computing. This study was carried out using multiple processor shared memory systems and massively parallel distributed memory systems. With the envisaged increase in anatomical and molecular detail in our cardiac models the requirement for HPC resources is predicted to increase many fold (&sim; 1&ndash;10 teraflops). Distributed computing is essential, both through massively parallel systems (a single supercomputer) and multiple parallel systems made accessible through the Grid. Analysis and interpretation of results are enhanced by HPV, which in itself is a large data computing aspect of cardiac modelling. Copyright &copy; 2008 John Wiley & Sons, Ltd.
Lower bounds on the depth of monotone arithmetic computations
Authors: D. Coppersmith, B. Schieber
Venue: Proceedings of the 33rd Annual Symposium on Foundations of Computer Science (1992)

Consider an arithmetic expression of length n involving only the operations (+,*) and non-negative constants. The authors prove lower bounds on the depth of any binary computation tree over the same set of operations and constants that computes such an expression. In their main result they exhibit a family of arithmetic expressions that requires computation trees of depth at least 1.5 log/sub 2/n-O(1). The authors also consider the family of arithmetic expressions defined by alternating 5-3 trees. For this family they show a tight bound of 5/(log/sub 2/15)log/sub 2/n+O(1) on the depth of any computation tree. This is the best known tight bound for any family of arithmetic expressions.