ppxscal/embedding_network huggingface dataset:
Scalable VPN routing via relaying
Authors: Changhoon Kim, Alexandre Gerber, Carsten Lund, Dan Pei, Subhabrata Sen
Venue: Proceedings of the 2008 ACM SIGMETRICS international conference on Measurement and modeling of computer systems (2008)

Enterprise customers are increasingly adopting MPLS (Multiprotocol Label Switching) VPN (Virtual Private Network) service that offers direct any-to-any reachability among the customer sites via a provider network. Unfortunately this direct reachability model makes the service provider's routing tables grow very large as the number of VPNs and the number of routes per customer increase. As a result, router memory in the provider's network has become a key bottleneck in provisioning new customers. This paper proposes Relaying, a scalable VPN routing architecture that the provider can implement simply by modifying the configuration of routers in the provider network, without requiring changes to the router hardware and software. Relaying substantially reduces the memory footprint of VPNs by choosing a small number of hub routers in each VPN that maintain full reachability information, and by allowing non-hub routers to reach other routers through a hub. Deploying Relaying in practice, however, poses a challenging optimization problem that involves minimizing router memory usage by having as few hubs as possible, while limiting the additional latency due to indirect delivery via a hub. We first investigate the fundamental tension between the two objectives and then develop algorithms to solve the optimization problem by leveraging some unique properties of VPNs, such as sparsity of traffic matrices and spatial locality of customer sites. Extensive evaluations using real traffic matrices, routing configurations, and VPN topologies demonstrate that Relaying is very promising and can reduce routing-table usage by up to 90%, while increasing the additional distances traversed by traffic by only a few hundred miles, and the backbone bandwidth usage by less than 10%.
Regularization using a parameterized trust region subproblem
Authors: Oleg Grodzevich, Henry Wolkowicz
Venue: Mathematical Programming: Series A and B (2008)

We present a new method for regularization of ill-conditioned problems, such as those that arise in image restoration or mathematical processing of medical data. The method extends the traditional trust-region subproblem, TRS, approach that makes use of the L-curve maximum curvature criterion, a strategy recently proposed to find a good regularization parameter. We apply a parameterized trust region approach to estimate the region of maximum curvature of the L-curve and find the regularized solution. This exploits the close connections between various parameters used to solve TRS. A MATLAB code for the algorithm is tested and a comparison to the conjugate gradient least squares, CGLS, approach is given and analysed.
Algorithm 879: EIGENTEST&mdash;a test matrix generator for large-scale eigenproblems
Authors: Che-Rung Lee, G. W. Stewart
Venue: ACM Transactions on Mathematical Software (TOMS) (2008)

Eigentest is a package that produces real test matrices with known eigensystems. A test matrix, called an eigenmat, is generated in a factored form, in which the user can specify the eigenvalues and has some control over the condition of the eigenvalues and eigenvectors. An eigenmat A of order n requires only O(n) storage for its representation. Auxiliary programs permit the computation of (A &minus; sI)b, (A &minus; sI)Tb, (A &minus; sI)&minus;1 b, and (A &minus; sI)&minus;T b in O(n) operations. A special routine computes specified eigenvectors of an eigenmat and the condition of its eigenvalue. Thus eigenmats are suitable for testing algorithms based on Krylov sequences, as well as others based on matrix-vector products. This article introduces the eigenmat and describes implementations in Fortran 77, Fortran 95, C, and Matlab.
Secure Web-Based Sharing of Health Information Services Using Ad-Hoc Dynamic Coalitions
Authors: S. Sampath, Ravi Iyer, K. S. Sridharan, Ravi Mukkamala, Sandhya Kapoor
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

Today, there is an increasing need for health-coalitions to handle situations such as the outbreak of diseases, earthquakes, or tsunamis throughout the world. Such situations arise most unexpectedly and need a rapid formation and deployment of a coalition of agencies to handle the situation. Interaction between coalition members (software systems) can be done using web services over the ubiquitous Internet. The coalition members securely share the information resources of the individual members. Absence of a means to guarantee such security, especially when interacting over the public Internet, prevents organizations from joining the coalitions. In this paper, we summarize the results of our work in building a prototype of health services coalition system. Our system offers confidentiality and integrity to all the participating members and the services they share by using secure web services. It employs a secure coalition service registry (CSR) for member organizations to register the services that they wish to share. It ensures that only authenticated members access the coalition. Finally, we describe the prototype and possible extensions to work.
Teaching complete embedded systems design process with graphical system design methodologies
Authors: Shekhar Sharad, Karl Muecke
Venue: Proceedings of the 13th International Conference on Parallel and Distributed Systems - Volume 02 (2007)

Embedded Systems Design is becoming essential for engineering students of all majors, not just electrical engineering or computer science. However, using traditional techniques to teach the embedded design process &#x2014; including the process to design, prototype and deploy an actual embedded system in a semester with traditional approaches presents substantial challenges to educators, especially teaching non-EE or CS majors. In this paper, we will explore an increasingly popular embedded design methodology that employs graphical design techniques to teach students the complete embedded systems design process in a semester and illustrate how graphical system design influences each of the three stages &#x2014; design, prototype and deploy with real-world examples
A database-oriented wrapper for ubiquitous data acquisition/access environments
Authors: Yuhei Akahoshi, Yutaka Kidawara, Katsumi Tanaka
Venue: Proceedings of the 2nd international conference on Ubiquitous information management and communication (2008)

Ubiquitous data acquisition/access environments are dynamic because the number and kinds of devices used to access information are constantly changing. System designers must often identify and incorporate devices and implement ad-hoc application systems based on the environment to execute tasks. The constant change in the environment and the huge number of devices make it difficult and time-consuming for system designers to construct application systems using existing programming styles. We propose a system construction platform based on a relational database mechanism. Devices and the functions are regarded as tables, tuples, and SQL queries. This platform makes it easy to manage huge numbers of devices in a ubiquitous data acquisition/access environment and provides a method of ad-hoc system construction that is accessible to many devices and can accommodate their functions.
APOGEE: automated project grading and instant feedback system for web based computing
Authors: Xiang Fu, Boris Peltsverger, Kai Qian, Lixin Tao, Jigang Liu
Venue: ACM SIGCSE Bulletin (2008)

Providing consistent, instant, and detailed feedback to students has been a great challenge in teaching Web based computing. We present the prototype of an automated grading system called ProtoAPOGEE for enriching students' learning experience and elevating faculty productivity. Unlike other automated graders used in introductory programming classes, ProtoAPOGEE emphasizes the examination of quality attributes of student project submissions, in addition to the basic functionality requirements. The tool is able to generate step by step play-back guidance for failed test cases, hence providing informative feedback to help students make reflective and iterative improvements in learning.
An attack on improved algebraic surface public-key cryptosystem (abstract only)
Authors: Maki Iwami
Venue: ACM Communications in Computer Algebra (2008)

Public key cryptography is widely used because it enables secure communication with a party accessing the site for the first time. But it is widely known that the quantum computers become available then the public key cryptosystems based on the discrete logarithm probrem such as RSA cryptosystem and Elliptic Curve cryptosystem will no longer be secure. To address these issues, Akiyama-Goto algebraic Surface Public-key Cryptosystem (ASC) was developed [1], and opened to general public at website as a research news of Toshiba corporation in 2005. Its security is based on a decision randomizing polynomial problem which is related to a problem of finding sections on fibered algebraic surfaces. This problem can be reduced to solving a multivariate equation system and it is known to be NP-complete. In 2007, in the case that public-key is in a certain form, Uchiyama and Tokunaga successed to attack in the sense of getting plain text from cipher text using reductions efficiently without solving section finding problem [2].And the abstract is introduced in CRYPTREC report 2006 [3] in the Appendix Chapter, which is known to be the important report related to e-Government recommended ciphers in Japan. Note that, at this point, the cryptosystem can be used safely if only we avoid to adopt using public key with vulnerability in the key generation step. However, the author suggested two algorithms applicable to all cases [5] i.e. the cryptosystem is completely broken. One is the generalization of Uchiyama-Tokunagas attack from polynomial ring over IFp to polynomial ring over rational function field. And the other takes advantages of Grobner base techniques so as to deal with in the polynomial ring over IFp. And in [6], the author also suggested methods for calculating zero point of the algebraic surface and a new attack utilizing it, and the approach resulted in the difficulty of making a suggestion of the invulnerable algebraic surface public-key cryptosystem without changing ideas progressively. On the other hand, Inanov-Volochs attack using trace map [9] was developed. In these background, Akiyama-Goto developed improved version of their Algebraic surface public-key cryptosystem (improved ASC) [8] on January 2008 [8] which has tolerance to Uchiyama-Gotos attack using reduction and Volochs attack using the trace map. Ivanov and Voloch suggested the substitution attack briefly on improved ASC in section 3 in [9], but the details are unspecified. In section 2, the improved ASC is described, and then, in section 3, a new reduction attack on the improved ASC is presented.
Latency and connectivity analysis tools for wireless mesh networks
Authors: Phoebus Chen, Shankar Sastry
Venue: Proceedings of the 1st international conference on Robot communication and coordination (2007)

There has been a recent rise in interest in building networked control systems over a wireless network, whether they be for robot navigation, multi-robot systems, or traditional industrial automation. The wireless networks in these systems must deliver packets between the controller and the actuators/sensors reliably and with low latency. Furthermore, they should be amenable to modeling and characterization so they can be designed as part of a complete control system. Mesh networks are particularly suited for control applications because they provide greater reliability through path diversity. This paper introduces tools for characterizing the end-to-end connectivity of two points in a wireless mesh network as a function of latency. In particular, we use tools derived from Markov chain models to compare end-to-end connectivity in two routing protocols running on the Data Link/MAC layer provided by Dust Network's Time Synchronized Mesh Protocol (TSMP): Directed Staged Flooding (DSF) and Dust Network's Unicast Path Diversity (UPD). These models also allow us to calculate the traffic load, the sensitivity of end-to-end connectivity to link estimation error, and the robustness of the network to node failure. The paper gives an example of how these tools can be used to evaluate the feasibility of running control applications over sensor networks.
AMABULO - A Model Architecture for Business Logic
Authors: Tobias Brückmann, Volker Gruhn
Venue: Proceedings of the 15th Annual IEEE International Conference and Workshop on the Engineering of Computer Based Systems (2008)

Models are widely used for communication and documentation purposes. They also tend to be used as parameters for code generation. Because these models have to be complete, consistent and correct we have to support modellers in keeping their models clean. The modeller should have the choice to select the preferred view and the needed level of detail for his modelling and model maintenance tasks. This paper proposes a model architecture named AMABULO for a model driven development process of business logic for information systems. The model architecture consists of a meta model, corresponding visual diagrams and an interchange format. With the use of AMABULO the development process for business logic is supported from analysis until code generation.
Teaching file input/output, loops, and if-statements via a red eye reduction assignment
Authors: Timothy Urness
Venue: Journal of Computing Sciences in Colleges (2008)

This paper describes a "nifty" programming assignment that requires students to use files, loops, and if-statements to implement an algorithm that will remove the red-eye artifact from an image. The assignment is most suitable for a CS1 course, but could be altered to accommodate a CS0 or CS2 course.
Proceedings of the 3rd international workshop on Sharing and reusing architectural knowledge
Venue: International Conference on Software Engineering (2008)

It is our great pleasure to welcome you to the 3rd Workshop on Sharing and Reusing Architectural Knowledge - SHARK 2008. This year's workshop continues its tradition of being the premier forum for intensive discussion and presentation of research results and experience reports on cutting-edge issues of the emerging field of Architectural Knowledge (AK). Over the past three years we have experienced an impressive increase in the number of research papers in scientific conferences and journals, dealing with architecture knowledge. There is also growing awareness between practitioners in the industry of the complicated issues and challenges that AK management (or lack thereof) entails. The mission of SHARK is to advance the state of the art and practice in the field of AK in both theory and practice. SHARK gives researchers and practitioners a unique opportunity to share their perspectives with others interested in the various aspects of this inter-disciplinary and multi-faceted field. The call for papers this year attracted 21 submissions from Europe, Asia, Latin America, Australia, the United States and Canada. The program committee accepted 13 papers that cover a variety of topics both directly related to AK, and also to other fields like requirements, patterns, evolution, Service-Oriented Architectures, Global Software Development, Embedded Systems and Software Product Lines. The resulting program reflects the truly multi-dimensional nature of this field. In addition, the program includes three invited talks that provide extra insight on three important aspects: Axel van Lamsweerde will discuss the Requirements Engineering perspective on AK; Jon Hal will argue that Requirements and Architecture are eventually two sides of the same coin; and Rich Hilliard will provide his insight on Architecture Documentation metamodels with respect to the international standard IEEE 1471 (revised into ISO/IEC 42010). We hope that these proceedings will serve as a valuable reference for AK researchers and practitioners.
User-generated descriptions of individual images versus labels of groups of images: A comparison using basic level theory
Authors: Abebe Rorissa
Venue: Information Processing and Management: an International Journal (2008)

Although images are visual information sources with little or no text associated with them, users still tend to use text to describe images and formulate queries. This is because digital libraries and search engines provide mostly text query options and rely on text annotations for representation and retrieval of the semantic content of images. While the main focus of image research is on indexing and retrieval of individual images, the general topic of image browsing and indexing, and retrieval of groups of images has not been adequately investigated. Comparisons of descriptions of individual images as well as labels of groups of images supplied by users using cognitive models are scarce. This work fills this gap. Using the basic level theory as a framework, a comparison of the descriptions of individual images and labels assigned to groups of images by 180 participants in three studies found a marked difference in their level of abstraction. Results confirm assertions by previous researchers in LIS and other fields that groups of images are labeled using more superordinate level terms while individual image descriptions are mainly at the basic level. Implications for design of image browsing interfaces, taxonomies, thesauri, and similar tools are discussed.
IR Drop Reduction via a Flip-Flop Resynthesis Technique
Authors: Jiun-Kuan Wu, Tsung-Yi Wu, Liang-Ying Lu, Kuang-Yao Chen
Venue: Proceedings of the 9th international symposium on Quality Electronic Design (2008)

Clock skew scheduling for peak current reduction is a conventional technique for solving IR-drop problem in physical design stage. In this paper, we propose two kinds of long delay flip-flops and a heuristic algorithm that is used to resynthesize flip-flops of a circuit. Because the switching times of flip-flops in the resynthesized circuit are staggered, the IR drop effect can be reduced. Unlike clock skew scheduling, our technique not only can be used in physical design stage but also in logic design stage. The other advantages of our technique over the clock skew optimization technique are that our technique has less area overhead and has more opportunities to find a better result.
An Expanded Stochastic Model in DAG Schemes
Authors: Kai Hu, Yan Jiang, Zhibin Yang, Shiran Chen
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

Previously, the second order moment of computation and communication times was taken into account in addition to their means in stochastic DAG schemes, in which the variation of computation and communication time caused by the heterogeneous distributed computing environment was considered. However, it is not optimal to consider only the variation caused by heterogeneous distributed computing environment. In this paper, it is proposed that the data placement policies of parallel program can also induce the variation of computation and communication time, and an expanded stochastic DAG is presented, in which the heterogeneity and the data placement policies of parallel program are considered together. Through the theoretic discursion of two matrix multiplying algorithms and experiments based on these two algorithms, the expanded definition has been validated. And the experiment results have been shown that a significant improvement in the parallel execution time of the expanded stochastic DAG can be achieved by optimizing the parallel algorithm, modifying the data placement policies and considering the heterogeneous environment.
Constant depth circuits, Fourier transform, and learnability
Authors: N. Linial
Venue: Proceedings of the 30th Annual Symposium on Foundations of Computer Science (1989)

Boolean functions in AC/sup O/ are studied using the harmonic analysis of the cube. The main result is that an AC/sup O/ Boolean function has almost all of its power spectrum on the low-order coefficients. This result implies the following properties of functions in AC/sup O/: functions in AC/sup O/ have low average sensitivity; they can be approximated well be a real polynomial of low degree; they cannot be pseudorandom function generators and their correlation with any polylog-wide independent probability distribution is small. An O(n/sup polylog(/ /sup sup)/ /sup (n)/)-time algorithm for learning functions in AC/sup O/ is obtained. The algorithm observed the behavior of an AC/sup O/ function on O(n/sup polylog/ /sup (n)/) randomly chosen inputs and derives a good approximation for the Fourier transform of the function. This allows it to predict with high probability the value of the function on other randomly chosen inputs.
Improved recommendation based on collaborative tagging behaviors
Authors: Shiwan Zhao, Nan Du, Andreas Nauerz, Xiatian Zhang, Quan Yuan, Rongyao Fu
Venue: Proceedings of the 13th international conference on Intelligent user interfaces (2008)

Considering the natural tendency of people to follow direct or indirect cues of other people's activities, collaborative filtering-based recommender systems often predict the utility of an item for a particular user according to previous ratings by other similar users. Consequently, effective searching for the most related neighbors is critical for the success of the recommendations. In recent years, collaborative tagging systems with social bookmarking as their key component from the suite of Web 2.0 technologies allow users to freely bookmark and assign semantic descriptions to various shared resources on the web. While the list of favorite web pages indicates the interests or taste of each user, the assigned tags can further provide useful hints about what a user thinks of the pages. In this paper, we propose a new collaborative filtering approach TBCF (Tag-based Collaborative Filtering) based on the semantic distance among tags assigned by different users to improve the effectiveness of neighbor selection. That is, two users could be considered similar not only if they rated the items similarly, but also if they have similar cognitions over these items. We tested TBCF on real-life datasets, and the experimental results show that our approach has significant improvement against the traditional cosine-based recommendation method while leveraging user input not explicitly targeting the recommendation system.
On the Consistency of Multiclass Classification Methods
Authors: Ambuj Tewari, Peter L. Bartlett
Venue: The Journal of Machine Learning Research (2007)

Binary classification is a well studied special case of the classification problem. Statistical properties of binary classifiers, such as consistency, have been investigated in a variety of settings. Binary classification methods can be generalized in many ways to handle multiple classes. It turns out that one can lose consistency in generalizing a binary classification method to deal with multiple classes. We study a rich family of multiclass methods and provide a necessary and sufficient condition for their consistency. We illustrate our approach by applying it to some multiclass methods proposed in the literature.