ppxscal/embedding_network huggingface dataset:
An economic model of the worldwide web
Authors: George Kouroupas, Elias Koutsoupias, Christos H. Papadimitriou, Martha Sideri
Venue: Special interest tracks and posters of the 14th international conference on World Wide Web (2005)

We believe that much novel insight into the worldwide web can be obtained from taking into account the important fact that it is created, used, and run by selfish optimizing agents: users, document authors, and search engines. On-going theoretical and experimental analysis of a simple abstract model of www creation and search based on user utilities illustrates this point: We find that efficiency is higher when the utilities are more clustered, and that power-law statistics of document degrees emerge very naturally in this context. More importantly, our work sets up many more elaborate questions, related, e.g., to www search algorithms seen as author incentives, to search engine spam, and to search engine quality and competition.
Quantum privacy and quantum wiretap channels
Authors: N. Cai, A. Winter, R. W. Yeung
Venue: Problems of Information Transmission (2004)

Following Schumacher and Westmoreland, we address the problem of the capacity of a quantum wiretap channel. We first argue that, in the definition of the so-called "quantum privacy," Holevo quantities should be used instead of classical mutual informations. The argument actually shows that the security condition in the definition of a code should limit the wiretapper's Holevo quantity. Then we show that this modified quantum privacy is the optimum achievable rate of secure transmission.
An analysis of search engine switching behavior using click streams
Authors: Yun-Fang Juan, Chi-Chao Chang
Venue: Special interest tracks and posters of the 14th international conference on World Wide Web (2005)

In this paper, we propose a simple framework to characterize the switching behavior between search engines based on click streams. We segment users into a number of categories based on their search engine usage during two adjacent time periods and construct the transition probability matrix across these usage categories. The principal eigenvector of the transposed transition probability matrix represents the limiting probabilities, which are proportions of users in each usage category at steady state. We experiment with this framework using click streams focusing on two search engines: one with a large market share and the other with a small market share. The results offer interesting insights into search engine switching. The limiting probabilities provide empirical evidence that small engines can still retain its fair share of users over time.
Application of Loop Reduction to Learning Program Behaviors for Anomaly Detection
Authors: Jidong Long, Daniel G. Schwartz, Sara Stoecklin, Mahesh K. Patel
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume I - Volume 01 (2005)

Evidence of some attacks can be manifested by abnormal sequences of system calls of programs. Most approaches that have been developed so far mainly concentrate on some program-specific behaviors and ignore some plain behaviors of programs. According to the concept of locality of reference, programs tend to spend most of their time on a few lines of code rather than other parts of the program. We use this finding to propose a method of loop reduction. A loop reduction algorithm, when applied to a series of system calls, eliminates redundant data. We did experiments for the comparison before and after loop reduction with the same detection approach. The preliminary results show that loop reduction improves the quality of training data by removing redundancy.
A statistics-based approach to incrementally update inverted files
Authors: Wann-Yun Shieh, Chung-Ping Chung
Venue: Information Processing and Management: an International Journal (2005)

Many information retrieval systems use the inverted file as indexing structure. The inverted file, however, requires inefficient reorganization when new documents are to be added to an existing collection. Most studies suggest dealing with this problem by sparing free space in an inverted file for incremental updates. In this paper, we propose a run-time statistics-based approach to allocate the spare space. This approach estimates the space requirements in an inverted file using only a little most recent statistical data on space usage and document update request rate. For best indexing speed and space efficiency, the amount of the spare space to be allocated is determined by adaptively balancing the trade-offs between reorganization reduction and space utilization. Experiment results show that the proposed space-sparing approach significantly avoids reorganization in updating an inverted file, and in the meantime, unused free space can be well controlled such that the file access speed is not affected.
Derandomization of auctions
Authors: Gagan Aggarwal, Amos Fiat, Andrew V. Goldberg, Jason D. Hartline, Nicole Immorlica, Madhu Sudan
Venue: Proceedings of the thirty-seventh annual ACM symposium on Theory of computing (2005)

We study the problem of designing seller-optimal auctions, i.e. auctions where the objective is to maximize revenue. Prior to this work, the only auctions known to be approximately optimal in the worst case employed randomization. Our main result is the existence of deterministic auctions that approximately match the performance guarantees of these randomized auctions. We give a fairly general derandomization technique for turning any randomized mechanism into an asymmetric deterministic one with approximately the same revenue. In doing so, we bypass the impossibility result for symmetric deterministic auctions and show that asymmetry is nearly as powerful as randomization for solving optimal mechanism design problems. Our general construction involves solving an exponential-sized flow problem and thus is not polynomial-time computable. To complete the picture, we give an explicit polynomial-time construction for derandomizing a specific auction with good worst-case revenue. Our results are based on toy problems that have a flavor similar to the hat problem from [3].
Object Recognition with Features Inspired by Visual Cortex
Authors: Thomas Serre, Lior Wolf, Tomaso Poggio
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 2 - Volume 02 (2005)

We introduce a novel set of features for robust object recognition. Each element of this set is a complex feature obtained by combining position- and scale-tolerant edge-detectors over neighboring positions and multiple orientations. Our systemýs architecture is motivated by a quantitative model of visual cortex. We show that our approach exhibits excellent recognition performance and outperforms several state-of-the-art systems on a variety of image datasets including many different object categories. We also demonstrate that our system is able to learn from very few examples. The performance of the approach constitutes a suggestive plausibility proof for a class of feedforward models of object recognition in cortex.
INTEGRATING USABILITY AND MARKETING ACTIVITIES: A METHOD FOR SUPPORTING ACCELERATED DESIGN STRATEGIES
Authors: R. Jay Ritchie, Judith A. List
Venue: ACM SIGCHI Bulletin (1991)

Although the practice of user-centered design is advocated in many organizations, engineering management issues may prevent early focus on system usability. Within the usability engineering cycle, practitioners consider task analysis and customer needs assessment a high priority. Market research activities occur early in the process, but usability information is not collected or passed to system developers. To improve and to accelerate the design process and to validate user preference findings, task analysis and market research surveys were performed concurrently during the design validation phase of a data communications product. The basic process steps included: forming a multidisciplinary team, identifying data sources, collecting data via interviews and event record review, transforming data into task models and product opinion matrices, and using the models and matrices to design a sample product. A number of benefits were observed using this method: improved economies of research and analysis time, increased strength of product opinion data, early product improvements, increased customer understanding of the product, and an improved product engineering process.
Design and evaluation of a TOP100 Linux Super Cluster system: Research Articles
Authors: Niklas Edmundsson, Erik Elmroth, Bo Kågström, Markus Mårtensson, Mats Nylén, Åke Sandgren, Mattias Wadenstein
Venue: Concurrency and Computation: Practice Experience (2004)

The High Performance Computing Center North (HPC2N) Super Cluster is a truly self-made high-performance Linux cluster with 240 AMD processors in 120 dual nodes, interconnected with a high-bandwidth, low-latency SCI network. This contribution describes the hardware selected for the system, the work needed to build it, important software issues and an extensive performance analysis. The performance is evaluated using a number of state-of-the-art benchmarks and software, including STREAM, Pallas MPI, the Atlas DGEMM, High-Performance Linpack and NAS Parallel benchmarks. Using these benchmarks we first determine the raw memory bandwidth and network characteristics; the practical peak performance of a single CPU, a single dual-node and the complete 240-processor system; and investigate the parallel performance for non-optimized dusty-deck Fortran applications. In summary, this &dollar;500&thinsp;000 system is extremely cost-effective and shows the performance one would expect of a large-scale supercomputing system with distributed memory architecture. According to the TOP500 list of June 2002, this cluster was the 94th fastest computer in the world. It is now fully operational and stable as the main computing facility at HPC2N. The system's utilization figures exceed 90&percnt;, i.e. all 240 processors are on average utilized over 90&percnt; of the time, 24 hours a day, seven days a week. Copyright &copy; 2004 John Wiley & Sons, Ltd.
Max-flow problem in undirected planar networks with node capacities being in NC
Authors: Xian-Chao Zhang, Ying-Yu Wan, Guo-Liang Chen
Venue: Journal of Computer Science and Technology (2004)

The max-flow problem in planar networks with only edge capacities has been proved to be in NC (Nickle's Class). This paper considers a more general version of the problem when the nodes as well as the edges have capacities. In a general network, the node-edge-capacity problem can be easily reduced to the edge-capacity problem. But in the case of planar network this reduction may destroy the planarity, and reduces the problem to the edge-capacity problem in a general network, which is P-complete. A recent contribution presents a new reduction for planar networks, that maintains the planarity. In this paper, it is proved that this reduction is in NC and thus the node-edge-capacity problem in undirected planar networks is in NC.
The MSOM Society Student Paper Competition: Extended Abstracts of 2004 Winners
Authors: Retsef Levi, Martin Pál, Robin O. Roundy, David B. Shmoys, Ravi Subramanian, Xinxin Hu, Gad Allon, Felipe Caro, Holly S. Lutze
Venue: Manufacturing Service Operations Management (2005)

As is our tradition at the journal, we are pleased to publish the extended abstracts from the winners of the 2004 MSOM Student Paper Competition. We do this to celebrate the achievements of these young scholars and provide you with the opportunity to learn about their work in more detail.The 2004 prize committee was chaired by Professor Phil Kaminsky (University of California, Berkeley). The other committee members were: Naren Agrawal (University of Santa Clara), Hyun-Soo Ahn (University of Michigan), Damian Beil (University of Michigan), Fernando Bernstein (Duke University), Izak Duenyas (University of Michigan), Wedad Elmaghraby (Georgia Institute of Technology), Jeremie Gallien (Massachusetts Institute of Technology), Teck Ho (University of Pennsylvania), Seyed Iravani (Northwestern University), Ananth Iyer (Purdue University), Eric Johnson (Dartmouth College), Roman Kapuscinski (University of Michigan), Pinar Keskinocak (Georgia Institute of Technology), Anton Kleywegt (Georgia Institute of Technology), Ãzalp Ãzer (Stanford University), Georgia Perakis (Massachusetts Institute of Technology), Alan Scheller-Wolf (Carnegie Mellon University), Sridhar Seshadri (New York University), Max Shen (University of California, Berkeley), David Simchi-Levi (Massachusetts Institute of Technology), Jay Swaminathan (University of North Carolina), Terry Taylor (Columbia University), Beril Toktay (INSEAD), Scott Webster (Syracuse University), and David Wu (Lehigh University).
Topic Detection in the news domain
Authors: Cormac Flynn, John Dunnion
Venue: Proceedings of the 2004 international symposium on Information and communication technologies (2004)

We discuss Topic Detection, a sub-task of the Topic Detection and Tracking (TDT) Project, and present initial results for both a baseline system and a set of extensions that attempt to model events and reportage in the news domain. Moreover, we describe a system that clusters live news feed and presents this data to the user in a variety of formats. We conclude that this system produces interesting and useful clusters, and outline some areas of future work.
Architectural Characterization of TCP/IP Packet Processing on the Pentium® M Microprocessor
Authors: Srihari Makineni, Ravi Iyer
Venue: Proceedings of the 10th International Symposium on High Performance Computer Architecture (2004)

A majority of the current and next generation server applications (web services, e-commerce, storage, etc.) employ TCP/IP as the communication protocol of choice. As a result, the performance of these applications is heavily dependent on the efficient TCP/IP packet processing within the termination nodes. This dependency becomes even greater as the bandwidth needs of these applications grow from 100 Mbps to 1Gbps to 10Gbps in the near future. Motivated by this, our work presented in this paper focuses on the following: (a) to understand the performance behavior of the various modes of TCP/IP processing, (b) to analyze the underlying architectural characteristics of TCP/IP packet processing and (c) to quantify the computational requirements of the TCP/IP packet processing component within realistic workloads. We achieve these goals by performing an in-depth analysis of packet processing performance on Intelýs state-of-the-art low power Pentium® M microprocessor running the Microsoft Windows* Server 2003 operating system. Some of our key observations are ¿(i) that the mode of TCP/IP operation can significantly affect the performance requirements, (ii) that transmit-side processing is largely computeintensive as compared to receive-side processing which is more memory-bound and (iii) that the computational requirements for sending/receiving packets can form a substantial component (28% to 40%) of commercial server workloads. From our analysis, we also discuss architectural as well as stack-related improvements that can help achieve higher server network throughput and result in improved application performance.
The PRC PAKTUS System: MUC-4 test results and analysis
Authors: Bruce Loatman
Venue: Proceedings of the 4th conference on Message understanding (1992)

In commenting on PRC's performance in MUC-3, we reported [1] that the component of our system that could most improve performance was discourse analysis. The MUC-4 exercise has strongly confirmed that view. We added a new discourse module to PAKTUS, made very few changes to the other system components, and the result was significantly improved performance. This paper discusses our test results, what we focused on for this task, what worked well, and what would improve performance further. A companion paper in this volume describes how our system functions.
Tuning query performance in mobile sensor databases
Authors: Vladimir Zadorozhny, Divyasheel Sharma, Prashant Krishnmurthy, Alexandros Labrinidis
Venue: Proceedings of the 6th international conference on Mobile data management (2005)

In this paper we propose a query-driven approach for tuning the time/energy trade-off in sensor networks with mobile sensors. The tuning factors include re-positioning of mobile sensors and changing their transmission ranges. We propose an algebraic query optimization framework that explores these factors while utilizing collision-free concurrent data transmissions with different degrees of data filtering and aggregation.
Exploiting Polymorphism in HW Design: a Case Study in the ATM Domain
Authors: Luigi Pomante
Venue: Proceedings of the international conference on Hardware/Software Codesign and System Synthesis: 2004 (2004)

The need of raising the level of abstraction and improving reuse in HW design suggests the adoption of an object-oriented (OO) design methodology based on SystemC-Plus (i.e. an enhanced SystemC). Such a methodology, developed during the ODETTE IST project, allows the exploitation of the key features of the OO paradigm (i.e. information hiding, inheritance, and polymorphism) at the behavioral level of description while guaranteeing synthesizability. In this context, the goal of this paper is to highlight advantages and drawbacks derived from the exploitation of polymorphism in the design of an ATM component: the UTOPIA Cells Handler.
Two-dimensional simultaneous subpixel estimation for area-based matching
Authors: Masao Shimizu, Masatoshi Okutomi
Venue: Systems and Computers in Japan (2005)

Area-based matching is a fundamental image processing operation to obtain the displacement between images. Also, the similarity interpolation method to estimate subpixel displacement is commonly used to enhance resolution. Conventionally, similarity interpolation estimation is performed by assuming that the horizontal and vertical displacements are independent. Almost no investigations of estimation error over the conventional method have been made, but it is inferred experientially that subpixel estimation with image interpolation or gradient-based methods is more precise than the similarity interpolation method. This paper proposes a novel 2D subpixel displacement estimation method based on similarity interpolation through modeling of 2D self-similarity. The proposed method requires no &ldquo;a priori&rdquo; knowledge of 2D similarity and no images at all. It adopts no iteration. Furthermore, the proposed method entails only slightly higher calculation costs than the conventional similarity interpolation method. The proposed method can obtain more precise estimation than both the conventional similarity interpolation method and the image interpolation method using comparison of subpixel estimation accuracy. An experiment using actual images demonstrates the effectiveness of the proposed method. &copy; 2005 Wiley Periodicals, Inc. Syst Comp Jpn, 36(2): 1&ndash;11, 2005; Published online in Wiley InterScience (). DOI 10.1002&sol;scj.20221
WILL THE REAL SCENARIO PLEASE STAND UP?
Authors: Robert L. Campbell
Venue: ACM SIGCHI Bulletin (1992)

At every phase of its development, human-computer interaction has had its devices for disabling critical thinking. In recent years, terms like "hypertext" and "groupware" have sometimes functioned that way. But such excesses have been countered by critical and debunking literature (e.g., Jones, 1987; Grudin, 1991). I would like to draw attention to another such device: the term "scenario". "Scenario" qualifies as a buzzword because it is extremely vague and has a myriad of uses. Indeed, it probably entered the HCI community from the US government bureaucracy, especially the military, where it remains a popular term for any detailed alternative possibility. Another established use is in business, in which a growth scenario describes the anticipated increase in demand for a product through the step-by-step fulfilment of a marketing plan.
dBBlue: low diameter and self-routing Bluetooth scatternet
Authors: Wen-Zhan Song, Xiang-Yang Li, Yu Wang, Weizhao Wang
Venue: Journal of Parallel and Distributed Computing (2005)

This paper addresses the problem of scatternet formation for single-hop Bluetooth-based wireless ad hoc networks, with minimal communication overhead. We adopt the well-known structure de Bruijn graph to form the backbone of Bluetooth scatternet, hereafter called dBBlue, such that every master node has at most seven slaves, every slave node is in at most two piconets, and no node assumes both master and slave roles. Our structure dBBlue also enjoys a nice routing property: the diameter of the graph is O(logn) and we can find a path with at most O(logn) hops for every pair of nodes without any routing table, where n is the total number of nodes in the network. Moreover, the network congestion is at most O(logn/n), assuming that a unit of total traffic demand is equally distributed among all pair of nodes. We discuss in detail a vigorous method to locally update the structure dBBlue using at most O(logn) communications when a node joins or leaves the network. In most cases, the cost of updating the scatternet is actually O(1) since a node can join or leave without affecting the remaining scatternet. The number of affected nodes is always bounded from above by a constant when a node joins or leaves the network. The dBBlue scatternet can be constructed incrementally when the nodes join the network one by one. To facilitate the self-routing and easy updating, a scalable MAC assignment mechanism is designed to guarantee the packet delivery even during scatternet updating. In addition, the structure formed by our method can sustain the faults of 2 nodes and the network is still guaranteed to be connected. If a node detects a fault of some neighboring master node or bridge slave node, it can dynamically re-route the packets and the path traveled by the packet is still at most O(logn) hops. Previously no method can guarantee all these properties although some methods can achieve some of the properties.
BINOCULAR: a system monitoring framework
Authors: Fatih Emekci, Sezai E. Tuna, Divyakant Agrawal, Amr El Abbadi
Venue: Proceeedings of the 1st international workshop on Data management for sensor networks: in conjunction with VLDB 2004 (2004)

Recent advances in hardware technology facilitate applications requiring a large number of sensor devices, where each sensor device has computational, storage, and communication capabilities. However these sensors are subject to certain constraints such as limited power, high communication cost, low computation capability, presence of noise in readings and low bandwidth. Since sensor devices are powered by ordinary batteries, power is a limiting resource in sensor networks and power consumption is dominated by communication. In order to reduce power consumption, we propose to use a linear model of temporal, spatial and spatio-temporal correlations among sensor readings. With this model, readings of all sensors can be estimated using the readings of a few sensors by using linear observers and multiple queries can be answered more efficiently. Since a small set of sensors are accessed for query processing, communication is significantly reduced. Furthermore, the proposed technique can also be beneficial at filtering out the noise which directly affects the accuracy of query results.
Tree-walking automata do not recognize all regular languages
Authors: Mikolaj Bojanczyk, Thomas Colcombet
Venue: Proceedings of the thirty-seventh annual ACM symposium on Theory of computing (2005)

Tree-walking automata are a natural sequential model for recognizing tree languages. Every tree language recognized by a tree-walking automaton is regular. In this paper, we present a tree language which is regular but not recognized by any (nondeterministic) tree-walking automaton. This settles a conjecture of Engelfriet, Hoogeboom and Van Best. Moreover, the separating tree language is definable already in first-order logic over a signature containing the left-son, right-son and ancestor relations.