ppxscal/embedding_network huggingface dataset:
A new two-server approach for authentication with short secrets
Authors: John Brainard, Ari Juels, Burt Kaliski, Michael Szydlo
Venue: Proceedings of the 12th conference on USENIX Security Symposium - Volume 12 (2003)

Passwords and PINs continue to remain the most widespread forms of user authentication, despite growing awareness of their security limitations. This is because short secrets are convenient, particularly for an increasingly mobile user population. Many users are interested in employing a variety of computing devices with different forms of connectivity and different software platforms. Such users often find it convenient to authenticate by means of passwords and short secrets, to recover lost passwords by answering personal or "life" questions, and to make similar use of relatively weak secrets. In typical authentication methods based on short secrets, the secrets (or related values) are stored in a central database. Often overlooked is the vulnerability of the secrets to theft en bloc in the event of server compromise. With this in mind, Ford and Kaliski and others have proposed various password "hardening" schemes involving multiple servers, with password privacy assured provided that some servers remain uncompromised. In this paper, we describe a new, two-server secure roaming system that benefits from an especially lightweight new set of protocols. In contrast to previous ideas, ours can be implemented so as to require essentially no intensive cryptographic computation by clients. This and other design features render the system, in our view, the most practical proposal to date in this area. We describe in this paper the protocol and implementation challenges and the design choices underlying the system.
Antfarm: tracking processes in a virtual machine environment
Authors: Stephen T. Jones, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
Venue: Proceedings of the annual conference on USENIX '06 Annual Technical Conference (2006)

In a virtualized environment, the VMM is the system's primary resource manager. Some services usually implemented at the OS layer, like I/O scheduling or certain kinds of security monitoring, are therefore more naturally implemented inside the VMM. Implementing such services at the VMM layer can be complicated by the lack of OS and application-level knowledge within a VMM. This paper describes techniques that can be used by a VMM to independently overcome part of the "semantic gap" separating it from the guest operating systems it supports. These techniques enable the VMM to track the existence and activities of operating system processes. Antfarm is an implementation of these techniques that works without detailed knowledge of a guest's internal architecture or implementation. An evaluation of Antfarm for two virtualization environments and two operating systems shows that it can accurately infer process events while incurring only a small 2.5% runtime overhead in the worst case. To demonstrate the practical benefits of process information in a VMM we implement an anticipatory disk scheduler at the VMM level. This case study shows that significant disk throughput improvements are possible in a virtualized environment by exploiting process information within a VMM.
Robust Adjusted Likelihood Function for Image Analysis
Authors: Rong Duan, Wei Jiang, Hong Man
Venue: Proceedings of the 35th Applied Imagery and Pattern Recognition Workshop (2006)

Model misspecification has been a major concern in practical model based image analysis. The underlying assumptions of generative processes usually can not exactly describe real-world data samples, which renders the maximum likelihood estimation (MLE) and the Bayesian decision methods unreliable. In this work we study a robust adjusted likelihood (RAL) function that can improve image classification performance under misspecified models. The RAL is calculated by raising the conventional likelihood function to a positive power and multiplying it with a scaling factor. Similar to model parameter estimation, these two new RAL parameters, i.e. the power and the scaling factor, are estimated from the training data using minimum error rate method. In two-category classification case, this RAL is equivalent to a linear discriminant function in loglikelihood space. To demonstrate the effectiveness of this RAL, we first simulate a model misspecification scenario, in which two Rayleigh sources are misspecified as Gaussian distributions. The Gaussian parameters and the RAL parameters are estimated accordingly from the training data, and the two RAL parameters are studied separately. The simulation results show that the Bayes decisions based on maximum-RAL yield higher classification accuracy than the decisions based on conventional maximum-likelihood. We further apply the RAL in automatic target recognition (ATR) of SAR images. Two target classes, i.e. t72 and bmp2, from MSTAR SAR target dataset are used in this study. The target signatures are modeled using Gaussian mixture models (GMMs) with five mixtures for each class. Image classification results again demonstrate a clear advantage of the proposed approach.
A proxy-based uncoordinated checkpointing scheme with pessimistic message logging for mobile grid systems
Authors: Nomica Imran, Imran Rao, Young-Koo Lee, Sungyoung Lee
Venue: Proceedings of the 16th international symposium on High performance distributed computing (2007)

Due to mobility, energy limitations, and unreliable wireless channels, applications running on mobile devices suffer from faults such as temporary disconnection and data loss. We, therefore, need a fault tolerance mechanism to guarantee their smooth working and performance. In this paper, we present a novel proxy-based uncoordinated checkpointing scheme with pessimistic message logging for efficient fault recovery in mobile Grid system. Simulation results show that this scheme is reliable, efficient and, at the sametime, consumes less network traffic.
The learning preferences of engineering students from two perspectives
Authors: P. Rosati
Venue: Proceedings of the 28th Annual Frontiers in Education - Volume 01 (1998)

The index of learning styles (ILS) is a self-report forced choice instrument created by Felder and Solomon which classifies the learning preferences of the respondent on four continuous scales: active/reflective; sensing/intuition; visual/verbal; and sequential/global. The ILS, although still under development, has already yielded insights into the learning preferences of engineering students and has shown significant differences between the average responses both of male and female students and also of first-year and fourth-year students. Additionally, a large group of engineering students at The University of Western Ontario (UWO), Canada, has completed both the ILS and also the well-known Myers-Briggs type indicator (MBTI). This UWO data reveals some strong connections between three of the ILS learning preference scales and the MBTI dimensions of psychological type. This paper presents the responses of engineering students to both the ILS and also to the MBTI. It also summarises the significant ILS response differences for male/female students, for first-year/fourth-year students and for students of different personality type on each of the four MBTI dimensions. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Cashmere: resilient anonymous routing
Authors: Li Zhuang, Feng Zhou, Ben Y. Zhao, Antony Rowstron
Venue: Proceedings of the 2nd conference on Symposium on Networked Systems Design & Implementation - Volume 2 (2005)

Anonymous routing protects user communication from identification by third-party observers. Existing anonymous routing layers utilize Chaum-Mixes for anonymity by relaying traffic through relay nodes called mixes. The source defines a static forwarding path through which traffic is relayed to the destination. The resulting path is fragile and shortlived: failure of one mix in the path breaks the forwarding path and results in data loss and jitter before a new path is constructed. In this paper, we propose Cashmere, a resilient anonymous routing layer built on a structured peer-to-peer overlay. Instead of single-node mixes, Cashmere selects regions in the overlay namespace as mixes. Any node in a region can act as the MIX, drastically reducing the probability of a mix failure. We analyze Cashmere's anonymity and measure its performance through simulation and measurements, and show that it maintains high anonymity while providing orders of magnitude improvement in resilience to network dynamics and node failures.
Understanding and dealing with operator mistakes in internet services
Authors: Kiran Nagaraja, Fábio Oliveira, Ricardo Bianchini, Richard P. Martin, Thu D. Nguyen
Venue: Proceedings of the 6th conference on Symposium on Opearting Systems Design & Implementation - Volume 6 (2004)

Operator mistakes are a significant source of unavailability in modern Internet services. In this paper, we first characterize these mistakes by performing an extensive set of experiments using human operators and a realistic three-tier auction service. The mistakes we observed range from software misconfiguration, to fault misdiagnosis, to incorrect software restarts. We next propose to validate operator actions before they are made visible to the rest of the system. We demonstrate how to accomplish this task via the creation of a validation environment that is an extension of the online system, where components can be validated using real workloads before they are migrated into the running service. We show that our prototype validation system can detect 66% of the operator mistakes that we have observed.
Numerical solutions of nonlinear evolution equations using variational iteration method
Authors: A. A. Soliman, M. A. Abdou
Venue: Journal of Computational and Applied Mathematics (2007)

The variational iteration method is used to solve three kinds of nonlinear partial differential equations, coupled nonlinear reaction diffusion equations, Hirota-Satsuma coupled KdV system and Drinefel'd-Sokolov-Wilson equations. Numerical solutions obtained by the variational iteration method are compared with the exact solutions, revealing that the obtained solutions are of high accuracy. He's variational iteration method is introduced to overcome the difficulty arising in calculating Adomian polynomial in Adomian method. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in mathematical physics.
Developing an Intelligent Assistant for Table Tennis Umpires
Authors: Patrick K. C. Wong
Venue: Proceedings of the First Asia International Conference on Modelling & Simulation (2007)

This paper outlines the idea and plan of developing an intelligent assistant for table tennis umpire in evaluating services. Table tennis is a fast sport. A service usually takes a few second to complete but there are many observations an umpire needs to take and makes a judgment before or soon after the service is complete. This is a complex task and the author believes the employment of videography, image processing and artificial intelligence (AI) technologies could help evaluating the service. The aim of this research is to develop an intelligent system which is able to track the location of the ball from live video images and evaluate the service according to the service rules. This is a pilot study and the focus is on the development of the techniques, rather than building a complete system. Various videography, image processing and artificial intelligence techniques will be experimented and evaluated. When a prototype system is built, it will be compared and tested against the judgements of a human umpire. Both the accuracy and rate of responses will be concerned. Furthermore, as well as aiding umpire, the system could also benefit players who want to have their services evaluated in real time without the need of having a human umpire present.
Signal-based design of wavelet filters
Authors: F. Moreau de Saint-Martin
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 03 (1996)

We address optimization and adaptation issues in designing the best wavelet filters for the representation or the compression of a given signal. A signal-based optimization technique is proposed and the application of this technique using different optimization criteria, corresponding to energy compaction, is considered. When applying this strategy to textures, for region-based image compression, we show that significant gain in a rate-distortion sense is achievable: up to 1.2 dB improvement is to be expected when compared to usual efficient filters (optimal in coding gain for AR(1) models). The choice of the optimization criterion is discussed for optimal performances in the rate-distortion sense.
Optimal suffix selection
Authors: Gianni Franceschini, S. Muthukrishnan
Venue: Proceedings of the thirty-ninth annual ACM symposium on Theory of computing (2007)

Given a string S[1·s n], the suffix selection problemis to find the kth lexicographically smallest amongst the n suffixes S[i·s n], for i=1,...,n. In particular, the fundamental question is if selection can be performed more efficiently than sorting all the suffixes. If one considered n numbers, they can be sorted using Θ(n log n) comparisonsand the classical result from 70's is that selection can be done using O(n) comparisons. Thus selection is provably more efficient than sorting, for n numbers. Suffix sorting can be done using Θ(n log n) comparisons, but does suffix selection need suffix sorting? We settle this fundamental problem by presenting an optimal, deterministic algorithm for suffix selection using O(n) comparisons.
Effort measurement in student software engineering projects
Authors: J. Tuya
Venue: Proceedings of the 30th Annual Frontiers in Education - Volume 01 (2000)

Teaching software engineering by means of student involvement in the team development of a product is the most effective way to teach the main issues of software engineering. Some of its difficulties are those of coordinating their work, measuring the time spent by the students (both in individual work and in meetings) and making sure that meeting time will not be excessive. Starting in the academic year 1998/1999, we assessed, improved and documented the development process for the student projects and found that measurement is one of the outstanding issues to be considered. Each week, the students report the time spent on the different project activities. We present and analyze the measurement results for our 16 student teams (each one with around 6 students). It is interesting to note that the time spent in meetings is usually too long, ranging from 46% in the requirements analysis phase to 21% in coding, mainly due to problems of coordination. Results from previous years are analyzed and presented to the following year's students for feedback. In the present year (2000), we have decreased the amount of time spent by the student doing group work, and improved the effectiveness and coordination of the teams.
Basic machine design software
Authors: R. Kumar
Venue: Proceedings of the 28th Annual Frontiers in Education - Volume 03 (1998)

Summary form only given. This abstract discusses software that is in the process of development and eventually will be used for the design of some basic electric machine mechanical components. Several textbooks and handbooks have been written about the machine elements as used in mechanical design. Although they have done an excellent job, educational software to automate the process is lacking. The textbooks cannot cover all the aspects of the design, as required for industrial applications, and complete the subject in a couple of semesters. On the other hand the information residing in handbooks is sometimes not as comprehensible as a textbook and, due to its voluminous size, finding data and facts is a cumbersome exercise. Keeping this in mind, this effort was undertaken to automate the design details of a variety of machine elements. This automation will help in information retrieval with ease and accuracy and also help to quickly perform design calculations. In its final form, the software will execute the design process by asking questions and then lead the end-user to select the appropriate factors and help in the mechanical component design. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Whodunit: transactional profiling for multi-tier applications
Authors: Anupam Chanda, Alan L. Cox, Willy Zwaenepoel
Venue: ACM SIGOPS Operating Systems Review (2007)

This paper is concerned with performance debugging of multi-tier applications, such as commonly found in servers and dynamic-content web sites. Existing tools and techniques for profiling such applications are not general enough to track and profile transactions in a generic multi-tier application. We propose transactional profiling that provides a general solution to this problem. We provide novel algorithms and techniques to track and profile transactions that flow through shared memory, events, stages or via interprocess communication using messages. We also measure interference among concurrent transactions. We describe the design and implementation of Whodunit, our prototype transactional profiler. We demonstrate the correctness of our proposed algorithm for tracking transaction flow through shared memory using Apache and MySQL. Using Whodunit we are able to track and profile transactions that flow through shared memory, events, stages or via message passing, and measure the interference among concurrent transactions. We illustrate the use of Whodunit in obtaining the transactional profile of web servers, a web proxy cache and a bookstore application.
Comparison of a neural network detector vs Neyman-Pearson optimal detector
Authors: D. Andina
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 06 (1996)

We optimize a neural network applied to binary detection such as those found in radar or sonar. Topics about designing the structure, training procedure and evaluating the performance, are discussed. The detector optimization is based on the use of a criterion function that yields a solution significantly superior to the typical sum-of-square-error. Using a modeled input, its performance is evaluated by Monte Carlo trials. As a result, detection curves are compared with the theoretical optimum ones (Neyman-Pearson detectors). For the model, and despite of the blind learning of the neural network, its performance is very close to optimal.
Point-to-Point Services in Hybrid Networks: Technologies and Performance Metrics
Authors: Athanassios Liakopoulos, Andreas Hanemann, Afrodite Sevasti
Venue: Proceedings of the Third International Conference on Networking and Services (2007)

Research networks, apart from pure IP packet-switched services, progressively introduce hybrid services, which combine packet switching and circuit switching technologies. Optical wavelengths (lambdas), SONET/SDH, 1/10 Gigabit Ethernet are examples of technologies stitched together in order to realize point-to-point (p2p) services that cross multiple domains. Network monitoring aims to detect anomalies, assess performance degradations and localize faults in a network. In this paper, we discuss the challenges of monitoring p2p hybrid services deployed in a multi-domain environment. We briefly discuss diverse methods of transporting Ethernet traffic over hybrid networks and present performance metrics related to various layer 1/2 technologies. We give an example of a hybrid service and discuss why it is challenging to identify service degradation problems in a multi-domain environment.
Exploiting partially overlapping channels in wireless networks: turning a peril into an advantage
Authors: Arunesh Mishra, Eric Rozner, Suman Banerjee, William Arbaugh
Venue: Proceedings of the 5th ACM SIGCOMM conference on Internet Measurement (2005)

Interference has always been considered as an unavoidable peril in wireless networks. A single data transmission is useful to some nodes and becomes interference to others. Based on channel of origin, interference can be categorized into co-channel (from transmissions on the same channel as the receiver) and adjacent-channel (transmissions on adjacent and overlapping channels). In this paper, we define specific mechanisms that can transform partially overlapped channels into an advantage, instead of a peril. We construct simple analytical and empirical models of such interference occurring in IEEE 802.11 networks, and illustrate two scenarios where such interference can be exploited. First, we apply partially overlapping channels to improve spatial channel re-use in Wireless LANs (WLANs). Second, we leverage such channels to enable nodes with a single radio interface to communicate more efficiently with their peers in 802.11 ad-hoc mode potentially using multi-hop paths. We evaluate both capabilities through testbed measurements.
The WHBA project: experiences "deeply embedding" NetBSD
Authors: Jason R. Thorpe, Allen K. Briggs
Venue: Proceedings of the BSD Conference 2003 on BSD Conference (2003)

Traditionally, use of BSD in an embedded application has been limited to "stand-alone" environments such as server appliances, wireless access points, and the control plane of routing equipment. Recently, Wasabi Systems was given the opportunity to use NetBSD in a more "deeply embedded" application, as the software on a PCI storage adapter card. This paper will introduce our specific application and describe the requirements of the storage adapter environment, the challenges presented by this type of environment, and the solutions we have developed to address these challenges, along with the results of our effort and some outstanding issues that warrant further study.
Argumentative feedback: a linguistically-motivated term expansion for information retrieval
Authors: Patrick Ruch, Imad Tbahriti, Julien Gobeill, Alan R. Aronson
Venue: Proceedings of the COLING/ACL on Main conference poster sessions (2006)

We report on the development of a new automatic feedback model to improve information retrieval in digital libraries. Our hypothesis is that some particular sentences, selected based on argumentative criteria, can be more useful than others to perform well-known feedback information retrieval tasks. The argumentative model we explore is based on four disjunct classes, which has been very regularly observed in scientific reports: PURPOSE, METHODS, RESULTS, CONCLUSION. To test this hypothesis, we use the Rocchio algorithm as baseline. While Rocchio selects the features to be added to the original query based on statistical evidence, we propose to base our feature selection also on argumentative criteria. Thus, we restrict the expansion on features appearing only in sentences classified into one of our argumentative categories. Our results, obtained on the OHSUMED collection, show a significant improvement when expansion is based on PURPOSE (mean average precision = +23%) and CONCLUSION (mean average precision = +41%) contents rather than on other argumentative contents. These results suggest that argumentation is an important linguistic dimension that could benefit information retrieval.