ppxscal/embedding_network huggingface dataset:
Efficient and secure source authentication with packet passports
Authors: Xin Liu, Xiaowei Yang, David Wetherall, Thomas Anderson
Venue: Proceedings of the 2nd conference on Steps to Reducing Unwanted Traffic on the Internet - Volume 2 (2006)

A key challenge in combating Denial of Service (DoS) attacks is to reliably identify attack sources from packet contents. If a source can be reliably identified, routers can stop an attack by filtering packets from the attack sources without causing collateral damage to legitimate traffic. This task is difficult because attackers may spoof arbitrary packet contents to hide their identities. This paper proposes a packet passport system to address this challenge. A packet passport efficiently and securely authenticates the source of a packet. A packet with a valid passport must have originated from the claimed source. The packet passport system can be incrementally deployed without introducing extra control messages. It also provides incentives for early adoption: a domain that deploys packet passport system can prevent other domains from spoofing its source identifiers. Our preliminary analysis suggests that the packet passport system can be implemented at high-speed routers with today's technologies.
Automated classification of non-functional requirements
Authors: Jane Cleland-Huang, Raffaella Settimi, Xuchang Zou, Peter Solc
Venue: Requirements Engineering (2007)

This paper describes a technique for automating the detection and classification of non-functional requirements related to properties such as security, performance, and usability. Early detection of non-functional requirements enables them to be incorporated into the initial architectural design instead of being refactored in at a later date. The approach is used to detect and classify stakeholders&#x2019; quality concerns across requirements specifications containing scattered and non-categorized requirements, and also across freeform documents such as meeting minutes, interview notes, and memos. This paper first describes the classification algorithm and then evaluates its effectiveness through reporting a series of experiments based on 30 requirements specifications developed as term projects by MS students at DePaul University. A new and iterative approach is then introduced for training or retraining a classifier to detect and classify non-functional requirements (NFR) in datasets dissimilar to the initial training sets. This approach is evaluated against a large free-form requirements document obtained from Siemens Logistics and Automotive Organization. Although to the NFR classifier is unable to detect all of the NFRs, it is useful for supporting an analyst in the error-prone task of manually discovering NFRs, and furthermore can be used to quickly analyse large and complex documents in order to search for NFRs.
A CMOS Low Voltage Charge Pump
Authors: Shantanu A. Bhalerao, Abhishek V. Chaudhary, Rajendra M. Patrikar
Venue: Proceedings of the 20th International Conference on VLSI Design held jointly with 6th International Conference: Embedded Systems (2007)

Charge pump circuits are used for obtaining higher voltages than normal power supply voltage in flash memories, DRAMs and low voltage designs. In this paper, we present a charge pump circuit in standard CMOS technology that is suited for low voltage operation. Our proposed charge pump uses a crossconnected NMOS cell as the basic element and PMOS switches are employed to connect one stage to the next. The simulated output voltages of the proposed 4 stage charge pump for input voltage of 0.9 V, 1.2 V, 1.5 V, 1.8 V and 2.1 V are 3.9 V, 5.1 V, 6.35 V, 7.51 V and 8.4 V respectively. This proposed charge pump is suitable for low power CMOS mixed-mode designs.
Coincidence Site Modules in 3-Space
Authors: Michael Baake, Peter Pleasants, Ulf Rehmann
Venue: Discrete Computational Geometry (2007)

The coincidence site lattice (CSL) problem and its generalization to &#x2124;-modules in Euclidean 3-space is revisited, and various results and conjectures are proved in a unified way, by using maximal orders in quaternion algebras of class number 1 over real algebraic number fields.
An empirical study of Chinese chunking
Authors: Wenliang Chen, Yujie Zhang, Hitoshi Isahara
Venue: Proceedings of the COLING/ACL on Main conference poster sessions (2006)

In this paper, we describe an empirical study of Chinese chunking on a corpus, which is extracted from UPENN Chinese Treebank-4 (CTB4). First, we compare the performance of the state-of-the-art machine learning models. Then we propose two approaches in order to improve the performance of Chinese chunking. 1) We propose an approach to resolve the special problems of Chinese chunking. This approach extends the chunk tags for every problem by a tag-extension function. 2) We propose two novel voting methods based on the characteristics of chunking task. Compared with traditional voting methods, the proposed voting methods consider long distance information. The experimental results show that the SVMs model outperforms the other models and that our proposed approaches can improve performance significantly.
A Vector Labeling Method for Solving Discrete Zero Point and Complementarity Problems
Authors: Gerard van der Laan, Dolf Talman, Zaifu Yang
Venue: SIAM Journal on Optimization (2007)

In this paper we establish the existence of a discrete zero point of a function from the $n$-dimensional integer lattice $\mathbb{Z}^n$ to the $n$-dimensional Euclidean space $\mathbb{R}^n$ under very general conditions with respect to the behavior of the function. The proof is constructive and uses a combinatorial argument based on a simplicial algorithm with vector labeling and lexicographic linear programming pivot steps. The algorithm provides an efficient method to find an exact solution. We also discuss how to adapt the algorithm for two related problems, namely, to find a discrete zero point of a function under a general antipodal condition and to find a solution to a discrete nonlinear complementarity problem. In both cases the modified algorithm provides a constructive existence proof, too. We further show that the algorithm for the discrete nonlinear complementarity problem generalizes the well-known Lemke&rsquo;s method to nonlinear environments. An economic application is also presented.
Sweeper: a lightweight end-to-end system for defending against fast worms
Authors: Joseph Tucek, James Newsome, Shan Lu, Chengdu Huang, Spiros Xanthos, David Brumley, Yuanyuan Zhou, Dawn Song
Venue: Proceedings of the 2nd ACM SIGOPS/EuroSys European Conference on Computer Systems 2007 (2007)

The vulnerabilities that plague computers cause endless grief to users. Slammer compromised millions of hosts in minutes; a hit-list worm would take under a second. Recently proposed techniques respond better than manual approaches, but require expensive instrumentation, which limits deployment. Although spreading "antibodies" (e.g. signatures) ameliorates this limitation, hosts depending on antibodies are defenseless until inoculation; to the fastest hit-list worms this delay is crucial. Additionally, most recently proposed techniques cannot provide recovery to provide continuous service after an attack. We propose a novel solution called Sweeper that provides both fast and accurate post-attack analysis and efficient recovery with low normal execution overhead. Sweeper in-novatively combines several techniques: (1) Sweeper uses lightweight monitoring techniques to detect a wide array of suspicious requests, providing a first level of defense. (2) By cleverly leveraging lightweight checkpointing, Sweeper postpones heavyweight monitoring until absolutely necessary --- after an attack is detected. Sweeper rolls back and re-executes multiple times to dynamically apply heavyweight analysis techniques via dynamic binary instrumentation. Since only the execution involved in the attack is analyzed, the analysis is efficient, yet thorough. (3) Based on the analysis results, Sweeper automatically generates low-overhead antibodies to prevent future attacks of the same vulnerability. (4) Finally, Sweeper again re-executes to perform fast recovery for continuous service. We implement Sweeper in a real system. Our experimental results with three real-world servers and four real security vulnerabilities show that Sweeper can detect an attack and generate antibodies in under 60 milliseconds. Our results also show that Sweeper imposes under 1% overhead during normal execution, clearly suitable for widespread production deployment (especially since Sweeper also allows partial deployment). Finally, we analytically show that, for a fast hit-list worm otherwise capable of infecting all vulnerable hosts in under a second, Sweeper contains the extent of infection to under 5%.
Computing Battery Lifetime Distributions
Authors: Lucia Cloth, Marijn R. Jongerden, Boudewijn R. Haverkort
Venue: Proceedings of the 37th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (2007)

The usage of mobile devices like cell phones, navigation systems, or laptop computers, is limited by the lifetime of the included batteries. This lifetime depends naturally on the rate at which energy is consumed, however, it also depends on the usage pattern of the battery. Continuous drawing of a high current results in an excessive drop of residual capacity. However, during intervals with no or very small currents, batteries do recover to a certain extend. We model this complex behaviour with an inhomogeneousMarkov reward model, following the approach of the so-called Kinetic battery Model (KiBaM). The state-dependent reward rates thereby correspond to the power consumption of the attached device and to the available charge, respectively. We develop a tailored numerical algorithm for the computation of the distribution of the consumed energy and show how different workload patterns influence the overall lifetime of a battery.
An empirical study of PLAD regression using the bootstrap
Authors: Athanassios Kondylis, Joe Whittaker
Venue: Computational Statistics (2007)

Partial LAD regression uses the L 1 norm associated with least absolute deviations (LAD) regression while retaining the same algorithmic structure of univariate partial least squares (PLS) regression. We use the bootstrap in order to assess the partial LAD regression model performance and to make comparisons to PLS regression. We use a variety of examples coming from NIR experiments as well as two sets of experimental data.
Adaptive space-time equalization for mobile receivers
Authors: J. S. Hammerschmidt
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 05 (2000)

We study the utilization of adaptive space-time (ST) signal processing for mobile receivers in frequency-selective cellular radio channels with cochannel interference and correlated fading. First, we introduce a bad urban spatio-temporal channel model for the perspective of a mobile multiple antenna receiver, present mobile array structures and inter-element correlations, and investigate cochannel interference conditions. We then conduct a comparative study for two promising combiner-equalizer structures, viz. a temporal decision-feedback equalizer (DFE) with a preselection diversity switch and a ST-DFE, all using recursive least squares (RLS) adaptation. Our results indicate that both techniques yield performance gains with respect to a single antenna receiver, with the more expensive joint space-time method often strongly superior to other setups. Finally, we present an efficient and stable structure for implementing the ST-DFE, using a QR-decomposition type of RLS adaptation.
Proceedings of the 12th ACM symposium on Access control models and technologies
Venue: Symposium on Access Control Models and Technologies (2007)

We are extremely pleased to have you at the 12th ACM SYMPOSIUM ON ACCESS CONTROL MODELS AND TECHNOLOGIES (SACMAT 2007) in Sophia Antipolis, France. SACMAT 2007 will be a forum for researchers and practitioners to discuss various timely topics in access control technologies and systems and their future directions. Access control has gone through numerous developments from access control for file systems to database systems and web-based computing systems architectures. Therefore, we hope that SACMAT 2007 will enable the generation of new paradigms for access control as well as enhance the existing approaches. The technical program, as in the past, has broad international participation of scholars and practitioners. It consists of 15 Sessions, including a keynote address, an industry report and two panels. We received 79 papers and selected 19 papers as regular papers and 9 papers as short papers. The topics vary from access control to trust management to privacy. All of the SACMAT 2007 papers were reviewed by those who are experts in the field. Each paper was reviewed by at least three reviewers and many of the papers had four reviews. Furthermore, extensive electronic discussions took place in making the selections for the symposium. We would like to express our sincere thanks to all the members of Program Committee for their efforts in evaluating and selecting the high quality papers. We would also like to express our special thanks to the Steering Committee of SACMAT 2007 for their enthusiastic support and encouragement for this workshop.
An on-the-fly bytecode compiler for Tcl
Authors: Brian T. Lewis
Venue: Proceedings of the 4th conference on USENIX Tcl/Tk Workshop, 1996 - Volume 4 (1996)

To improve the speed of interpreting Tcl programs, we are developing an on-the-fly bytecode compiler as part of the Tcl project at Sun Microsystems Laboratories. This new compilation system supports dual-ported objects that are stored in Tcl variables and passed to procedures instead of strings. These objects allow faster integer, list, and other operations by including an appropriate internal representation in addition to a string. Early performance results show significant improvement for some scripts. On a 167MHz UltraSPARC 1, lindex of the last element of a 100 element list takes 3 microseconds compared to 72 for the current Tcl interpreter. A set command that stores a new value in a local variable now takes less than 1 microsecond vs. 5.8 to 10 microseconds (depending on the length of the variable name) for the current system. This paper describes the design of the compiler and its current state, outlines its development plan, and gives some early performance results. It also describes some implications of the compiler for Tcl script and extension writers, and describes how to best take advantage of the compiler.
Analytical router modeling for networks-on-chip performance analysis
Authors: Umit Y. Ogras, Radu Marculescu
Venue: Proceedings of the conference on Design, automation and test in Europe (2007)

Networks-on-Chip (NoCs) have recently emerged as a scalable alternative to classical bus and point-to-point architectures. To date, performance evaluation of NoC designs is largely based on simulation which, besides being extremely slow, provides little insight on how different design parameters affect the actual network performance. Therefore, it is practically impossible to use simulation for optimization purposes. In this paper, we first present a generalized router model and then utilize this novel model for doing NoC performance analysis. The proposed model can be used not only to obtain fast and accurate performance estimates, but also to guide the NoC design process within an optimization loop. The accuracy of our approach and its practical use is illustrated through extensive simulation results.
Metadata Integration and Media Transcoding in Universal-Plug-and-Play (UPnP) Enabled Networks
Authors: M. Jakab, M. Kropfberger, M. Ofner, R. Tusch, H. Hellwagner, L. Boszormenyi
Venue: Proceedings of the 15th Euromicro International Conference on Parallel, Distributed and Network-Based Processing (2007)

Universal Plug and Play (UPnP) is a widely accepted standard for automatically detecting devices and services in a local area network as well as for describing and controlling them. In order to deal with multimedia devices and especially content, in 2002 the UPnP-AV standard definition was released. It defines device and service descriptions for Media Servers and Renderers. Thereby, the Media Server's Content Directory Service allows an easy management and the exchange of metadata about the provided media data. Media content became browsable by semantic meta information about it. There are still two major drawbacks of UPnP-AV, which make its usage in real world multimedia communication scenarios very difficult. First, searching for similar content on distributed Media Servers with a huge number of media files is not economically possible. Second, the media content must be consumed by Renderers as provided by the Servers, independently of their terminal capabilities and network connections. In order to deal with these two drawbacks, this work proposes a novel approach of metadata integration and media transcoding in UPnP networks. First, the Media Server is extended by a Control Point which offers discovery of other Media Servers and fetches metadata from their Content Directories. Furthermore, it integrates the gathered information in its own Content Directory. Control Points are then able to query this Integrating Media Server for a desired content, and get a network-complete search result. Second, terminal and network capabilities of the Render- ers are taken into account in order to transcode and transmit the content in a suitable way for the consuming device. These two approaches of metadata integration and media data adaptation enable searchable logical views on tailored multimedia content in UPnP-AV networks.
Mining periodic patterns with gap requirement from sequences
Authors: Minghua Zhang, Ben Kao, David W. Cheung, Kevin Y. Yip
Venue: ACM Transactions on Knowledge Discovery from Data (TKDD) (2007)

We study a problem of mining frequently occurring periodic patterns with a gap requirement from sequences. Given a character sequence S of length L and a pattern P of length l, we consider P a frequently occurring pattern in S if the probability of observing P given a randomly picked length-l subsequence of S exceeds a certain threshold. In many applications, particularly those related to bioinformatics, interesting patterns are periodic with a gap requirement. That is to say, the characters in P should match subsequences of S in such a way that the matching characters in S are separated by gaps of more or less the same size. We show the complexity of the mining problem and discuss why traditional mining algorithms are computationally infeasible. We propose practical algorithms for solving the problem and study their characteristics. We also present a case study in which we apply our algorithms on some DNA sequences. We discuss some interesting patterns obtained from the case study.
Mobile Devices for Personal Smart Spaces
Authors: Ivan Marsa-Maestre, Miguel A. Lopez-Carmona, Juan R. Velasco, Alvaro Paricio
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 02 (2007)

Personal mobile devices are on the way to become fully integrated in our everyday lives. Cell phones and PDAs, for instance, already offer their users some kinds of service personalization, like phone directories or calendar management. But service personalization through personal mobile devices can be taken one step further. In particular, we believe that personal devices can be used to integrate services provided within smart environments with the services provided at the personal devices themselves. In this paper, we present an approach for the seamless integration of personal devices and smart environments through the use of personal smart spaces.
Recommender systems and their impact on sales diversity
Authors: Daniel M. Fleder, Kartik Hosanagar
Venue: Proceedings of the 8th ACM conference on Electronic commerce (2007)

This paper examines the effect of recommender systems on the diversity of sales. Two anecdotal views exist about such effects. Some believe recommenders help consumers discover new products and thus increase sales diversity. Others believe recommenders only reinforce the popularity of already popular products. This paper is a first attempt to reconcile these seemingly incompatible views. We explore the question in two ways. First, modeling recommender systems analytically allows us to explore their path dependent effects. Second, turning to simulation, we increase the realism of our results by combining choice models with actual implementations of recommender systems. We arrive at three main results. One, some common recommenders lead to a net reduction in average sales diversity. Two, there exists path dependence, and in individual instances the same recommender can either increase or decrease diversity. Three, we show how basic design choices affect the outcome.
Structure-driven algorithms for equivalence verification and infeasibility checking
Authors: Karem A. Sakallah
Venue:  (2006)

Today's digital systems are at the forefront of modern technology. Electronic chips with a billion transistors are not a farfetched goal. For digital systems to continue pervading our lives, we must strive to build rigorous technologies for designing them and ensuring their functional correctness. The difficulty of this problem is a direct consequence of its inherent computational intractability; the design and verification tasks requires extensive computational resources. In this thesis, we tackle this problem by constructing scalable algorithms for verifying the correctness of these systems as well as identifying infeasiblities during their design.Our work addresses one problem of formal verification known as sequential equivalence verification. Despite considerable research, sequential verification algorithms are hindered by the inherent "state explosion" problem. Our premise is that verifying the sequential equivalence of actual circuits should be tractable. The simple intuition behind this assertion is that human designers routinely create "complex" designs and are able to cope with them. The inability of automatic verification tools to analyze these designs is due to their failure to recognize, and judiciously account for, the structure present in these systems. Thus, we explore and develop a battery of techniques whose aim is to identify and effectively utilize knowledge derived from the structure of real-life verification tasks.Identifying the causes of infeasibility of a set of contraints frequently arises during the design and verification of digital systems. These systems are modeled using Boolean formulas whose unsatisfiability usually identifies a problem that needs to be diagnosed and fixed. In design applications, for example, a large Boolean function is formed such that a feasible design is obtained when the function is satisfiable, and design infeasibility is indicated when the function is unsatisfiable. Without further analysis of the causes of unsatisliability, we have no clue as to what design constraints must be modified to make the design feasible. We develop algorithms for identifying the causes of infeasibility by extracting minimal unsatisfiable subformulas. We present algorithms for extracting single and multiple such subformulas as well as algorithms for extracting the smallest of such formulas in terms of its number of constraints.