ppxscal/embedding_network huggingface dataset:
Learning to Classify Documents with Only a Small Positive Training Set
Authors: Xiao-Li Li, Bing Liu, See-Kiong Ng
Venue: Proceedings of the 18th European conference on Machine Learning (2007)

Many real-world classification applications fall into the class of positive and unlabeled (PU) learning problems. In many such applications, not only could the negative training examples be missing, the number of positive examples available for learning may also be fairly limited due to the impracticality of hand-labeling a large number of training examples. Current PU learning techniques have focused mostly on identifying reliable negative instances from the unlabeled set U. In this paper, we address the oft-overlooked PU learning problem when the number of training examples in the positive set P is small. We propose a novel technique LPLP (Learning from Probabilistically Labeled Positive examples) and apply the approach to classify product pages from commercial websites. The experimental results demonstrate that our approach outperforms existing methods significantly, even in the challenging cases where the positive examples in P and the hidden positive examples in U were not drawn from the same distribution.
SERvartuka: Dynamic Distribution of State to Improve SIP Server Scalability
Authors: Vijay A. Balasubramaniyan, Arup Acharya, Mustaque Ahamad, Mudhakar Srivatsa, Italo Dacosta, Charles P. Wright
Venue: Proceedings of the 2008 The 28th International Conference on Distributed Computing Systems (2008)

A growing class of applications, including VoIP, IM and Presence, are enabled by the Session Initiation Protocol (SIP). Requests in SIP typically traverse through multiple proxies. The availability of multiple proxies offers the flexibility to distribute proxy functionality across several nodes. In particular, after experimentally demonstrating that the resource consumption of maintaining state is significant, we define the problem of state distribution across multiple nodes when the goal is to increase overall call throughput. We first formulate this as an optimization problem and then derive a distributed algorithm from it. This distributed algorithm leads to the design and evaluation of SERvartuka, a more scalable SIP server that dynamically determines the number of SIP requests for which the server is stateful while delegating state maintenance for the remainder of the requests to a server further downstream. This design is in contrast to existing SIP servers that are statically configured to either be stateless or stateful and therefore result in sub-optimal call throughput. We implement SERvartuka on top of OpenSER, a commercial SIP proxy server and measure performance benefits of different server configurations. An example of our results is a 20% percent increase in call throughput when using our algorithm for a configuration of two servers in series.
A multi-layer fpga framework supporting autonomous runtime partial reconfiguration
Authors: Ronald F. Demara
Venue:  (2007)

Partial reconfiguration is a unique capability provided by several Field Programmable Gate Array (FPGA) vendors recently, which involves altering part of the programmed design within an SRAM-based FPGA at run-time. In this dissertation, a Multilayer Runtime Reconfiguration Architecture (MRRA) is developed, evaluated, and refined based on this technique for Autonomous Runtime Partial Reconfiguration of FPGA devices. Under the proposed MRRA paradigm, FPGA configurations can be manipulated at runtime using on-chip resources. Operations are partitioned into Logic, Translation, and Reconfiguration layers along with a standardized set of Application Programming Interfaces (APIs). At each level, resource details are encapsulated and managed for efficiency and portability during operation. An MRRA mapping theory is developed to link the general logic function and area allocation information to the device related physical configuration level data by using mathematical data structure and physical constraints. In some special certain scenarios, configuration bit stream data can be read and modified directly for fast operations, relying on the use of similar logic functions and common interconnection resources for communication. A corresponding logic control flow is also developed for MRRA to make the entire process autonomous.Several prototype MRRA systems are developed on a Xilinx Virtex II Pro platform. The Virtex II Pro on-chip PowerPC core and block RAM are employed to manage control operations while multiple physical interfaces establish and supplement autonomous reconfiguration capabilities. Area, speed and power optimization techniques are developed based on the developed Xilinx prototype. Evaluations and analysis of these prototype and techniques are performed on a number of benchmark and hashing algorithm case studies. The results indicate that the resource utilization, run-time performance and power consumptions using the developed architecture and approaches all achieve significant improvement compared with Xilinx proposed baseline reconfiguration flow.The Genetic Algorithm (GA) for FPGA fault tolerance is finally tested as an ultimate high-level application running on this architecture. It demonstrated that this is a hardware and software infrastructure that enables an FPGA to dynamically reconfigure itself efficiently under the control of a soft microprocessor core that is instantiated within the FPGA fabric. Such a system combines the benefits of intelligent control, fast reconfiguration and low overhead.
Enhancing Topology Preservation during Neural Field Development Via Wiring Length Minimization
Authors: Claudius Gläser, Frank Joublin, Christian Goerick
Venue: Proceedings of the 18th international conference on Artificial Neural Networks, Part I (2008)

We recently proposed a recurrent neural network model for the development of dynamic neural fields [1]. The learning regime incorporates homeostatic processes, such that the network is able to self-organize and maintain a stable operation mode even in face of experience-driven changes in synaptic strengths. However, the learned mappings do not necessarily have to be topology preserving. Here we extend our model by incorporating another mechanism which changes the positions of neurons in the output space. This algorithm operates with a purely local objective function of minimizing the wiring length and runs in parallel to the above mentioned learning process. We experimentally show that the incorporation of this additional mechanism leads to a significant decrease in topological defects and further enhances the quality of the learned mappings. Additionally, the proposed algorithm is not limited to our network model; rather it can be applied to any type of self-organizing maps.
Self-orienting wireless multimedia sensor networks for occlusion-free viewpoints
Authors: Nurcan Tezcan, Wenye Wang
Venue: Computer Networks: The International Journal of Computer and Telecommunications Networking (2008)

Wireless multimedia sensor networks (WMSN) are formations of a large number of compact form-factor computing devices that can capture multimedia content, such as video and audio, and communicate them over wireless channels. The efficiency of a WMSN heavily depends on the correct orientation (i.e., view) of its individual sensory units in the field. In this paper, we study the problem of self-orientation in WMSN, that is finding the most beneficial orientation for all multimedia sensors to maximize multimedia coverage. We propose a new algorithm to determine a node's multimedia coverage and find the sensor orientation that minimizes the negative effect of occlusions and overlapping regions in the sensing field. Our approach enables multimedia sensor nodes to compute their directional coverage leading to an efficient and self-configurable sensor orientation calculation. By using simulations, we show that the occlusion-free viewpoint approach increases the multimedia coverage significantly. The self-orientation methodology is designed in the form of a distributed algorithm, making it a suitable candidate for deployment in practical systems.
Transversal Waves in Nonlinear Signorini Model
Authors: Carlo Cattani, Ekaterina Nosova
Venue: Proceeding sof the international conference on Computational Science and Its Applications, Part I (2008)

Propagation of waves in hyperelastic composite materials is studied by using a nonlinear model based on Signorini potential. The nonlinear wave solution, excited by an ingoing transversal pulse, and the corresponding nonlinear effects are discussed and simulated.
Hack-a-Vote: Security Issues with Electronic Voting Systems
Authors: Jonathan Bannet, David W. Price, Algis Rudys, Justin Singer, Dan S. Wallach
Venue: IEEE Security and Privacy (2004)

In a quest for election legitimacy, officials are increasingly deploying direct recording electronic (DRE) voting systems. A project to assess their trustworthiness revealed both the ease of introducing bugs into such systems and the difficulty of detecting them during audits.
Hardware and software architecture for power quality analysis
Authors: Ricardo Lima, Damián Quiroga, Claudio Reineri, Fernando Magnago
Venue: Computers and Electrical Engineering (2008)

This paper presents a novel concept for power quality hardware and software architecture. Software tools related to detection, classification and characterization of power quality events can be integrated into a Distribution Control Center in which the interconnection between different subsystems is being carried out through the Internet allowing flexibility to the system. This system is implemented using wavelet analysis applied in all proposed algorithms. Different power quality events are taken as examples to illustrate the capabilities of the proposed method. The obtained results reveal that the proposed architecture is feasible to be implemented as an integral part of a control center system. The proposed system has the property of fast and accurate detection and classification of any power quality disturbance event and introduces a new PQ index determination that allows characterizing any type of disturbance including the non-periodic signals.
LS-Plan: An Effective Combination of Dynamic Courseware Generation and Learning Styles in Web-Based Education
Authors: Carla Limongelli, Filippo Sciarrone, Giulia Vaste
Venue: Proceedings of the 5th international conference on Adaptive Hypermedia and Adaptive Web-Based Systems (2008)

This paper presents LS-Plan, a system capable of providing Educational Hypermedia with adaptation and personalization. The architecture of LS-Plan is based on three main components: the Adaptation Engine, the Planner and the Teacher Assistant. Dynamic course generation is driven by an adaptation algorithm, based on Learning Styles, as defined by Felder-Silverman's model. The Planner, based on Linear Temporal Logic, produces a first Learning Objects Sequence, starting from the student's Cognitive State and Learning Styles, as assessed through pre-navigation tests. During the student's navigation, and on the basis of learning assessments, the adaptation algorithm can propose a new Learning Objects Sequence. In particular, the algorithm can suggest different learning materials either trying to fill possible cognitive gaps or by re-planning a newly adapted Learning Objects Sequence. A first experimental evaluation, performed on a prototype version of the system, has shown encouraging results.
A Branch and Bound Algorithm for Max-Cut Based on Combining Semidefinite and Polyhedral Relaxations
Authors: Franz Rendl, Giovanni Rinaldi, Angelika Wiegele
Venue: Proceedings of the 12th international conference on Integer Programming and Combinatorial Optimization (2007)

In this paper we present a method for finding exact solutions of the Max-Cut problem max x T Lx such that x ¿ { ¿ 1,1} n . We use a semidefinite relaxation combined with triangle inequalities, which we solve with the bundle method. This approach is due to [12] and uses Lagrangian duality to get upper bounds with reasonable computational effort. The expensive part of our bounding procedure is solving the basic semidefinite programming relaxation of the Max-Cut problem.We review other solution approaches and compare the numerical results with our method. We also extend our experiments to unconstrained quadratic 0-1 problems and to instances of the graph bisection problem.The experiments show, that our method nearly always outperforms all other approaches. Our algorithm, which is publicly accessible through the Internet, can solve virtually any instance with about 100 variables in a routine way.
Reflections on the Role of Static Analysis in Cooperative Bug Isolation
Authors: Ben Liblit
Venue: Proceedings of the 15th international symposium on Static Analysis (2008)

Cooperative Bug Isolation (CBI) is a feedback-directed approach to improving software quality. Developers provide instrumented applications to the general public, and then use statistical methods to mine returned data for information about the root causes of failure. Thus, users and developers form a feedback loop of continuous software improvement. Given CBI's focus on statistical methods and dynamic data collection, it is not clear how static program analysis can most profitably be employed. We discuss current uses of static analysis during CBI instrumentation and failure modeling. We propose novel ways in which static analysis could be applied at various points along the CBI feedback loop, from fairly concrete low-level optimization opportunities to hybrid failure-modeling approaches that may cut across current static/dynamic/statistical boundaries.
Data Failures
Authors: Simona Orzan, Mohammad Torabi Dashti
Venue: Proceedings of the 22nd international symposium on Distributed Computing (2008)

To improve the theoretical understanding of the byzantine model and enable a modular design of algorithms, we propose to decompose the byzantine behaviour into a data failure behaviour and a communication failure behaviour. We argue that the two failure types are orthogonal and we point out how they generate a range of several new interesting failure models, which are less difficult than byzantine, but different than the already well understood crash model. Such intermediate models are relevant and subject to recent studies, e.g. [2].
Evaluating the Effect of Tomosynthesis Acquisition Parameters on Image Texture: A Study Based on an Anthropomorphic Breast Tissue Software Model
Authors: Despina Kontos, Cuiping Zhang, Nicole Ruiter, Predrag R. Bakic, Andrew D. Maidment
Venue: Proceedings of the 9th international workshop on Digital Mammography (2008)

Mammographic texture features have been shown to correlate with the risk of developing breast cancer. Digital breast tomosynthesis (DBT) is an emerging 3D x-ray breast imaging modality with superior tissue visualization compared to mammography, having the potential to provide more accurate estimation of parenchymal texture features. In this paper, we investigate the effect of DBT acquisition parameters on computer-extracted texture features. DBT images were simulated using an anthropomorphic breast tissue software model allowing for variations in DBT acquisition geometry. Our results show that DBT acquisition geometry appears to have an impact on the computed texture features; angular range appears to have a greater effect than the selected number of source projections. We attribute this effect to the differences in image quality resulting from the different reconstruction geometries. Our ultimate goal is to determine the DBT acquisition geometry that provides the optimal image quality to estimate parenchymal texture.
Technical communique: New stability criteria for linear systems with interval time-varying delay
Authors: Xiefu Jiang, Qing-Long Han
Venue: Automatica (Journal of IFAC) (2008)

This paper investigates robust stability of uncertain linear systems with interval time-varying delay. The time-varying delay is assumed to belong to an interval and is a fast time-varying function. The uncertainty under consideration includes polytopic-type uncertainty and linear fractional norm-bounded uncertainty. A new Lyapunov-Krasovskii functional, which makes use of the information of both the lower and upper bounds of the interval time-varying delay, is proposed to drive some new delay-dependent stability criteria. In order to obtain much less conservative results, a tighter bounding for some term is estimated. Moreover, no redundant matrix variable is introduced. Finally, three numerical examples are given to show the effectiveness of the proposed stability criteria.
Electro-Optical DSP of Tera Operations per Second and Beyond (Extended Abstract)
Authors: Dan E. Tamir, Natan T. Shaked, Peter J. Wilson, Shlomi Dolev
Venue: Proceedings of the 1st international workshop on Optical SuperComputing (2008)

We present a vector-by-matrix multiplier architecture incorporating the high potential of optical computing within electronics. This architecture stems from advances in optical switching technology, optical communication, and laser on silicon, and overcomes previous bottlenecks implied by the speed of transferring information to the optical vector-by-matrix multiplier. Based on this architecture, we present in detail a feasible electro-optical DSP co-processor that can obtain more than 16-Tera integer operations per second. The use of the new architecture for several principal DSP applications is detailed, showing a significant improvement of at least two orders of magnitudes, over existing DSP technologies. Examples of possible applications, including motion estimation engine, string matching, and geometry engine systems, are provided. In addition, the architecture enables an improvement of previous solutions to bounded NP-complete problems by extensively reducing the size of the solver, while preserving an efficient computation time.
Experience report: erlang in acoustic ray tracing
Authors: Christian Convey, Andrew Fredricks, Christopher Gagner, Douglas Maxwell, Lutz Hamel
Venue: ACM SIGPLAN Notices (2008)

We investigated the relative merits of C++ and Erlang in the implementation of a parallel acoustic ray tracing algorithm for the U.S. Navy. We found a much smaller learning curve and better debugging environment for parallel Erlang than for pthreads-based C++ programming. Our C++ implementation outperformed the Erlang program by at least 12x. Attempts to use Erlang on the IBM Cell BE microprocessor were frustrated by Erlang's memory footprint.
Topic 8: Distributed Systems and Algorithms
Authors: Elsa María Macías López, Marc Shapiro
Venue: Proceedings of the 14th international Euro-Par conference on Parallel Processing (2008)

Fifteen papers were submitted to Topic 8. Each paper was reviewed by four of the topic chairs (a single paper received only three reviews). Three papers were ranked clearly above the others and three others were discussed in more depth between the chairs. As a result, the chairs proposed three papers for acceptance, and two more for discussion, one of which was accepted by the PC meeting.It is interesting to note that none of the top papers is a "hard-core" distributed systems paper, i.e., this year, there will be no papers on consensus, fault tolerance, or distributed algorithms. Instead all four papers focus on applications of distributed systems. This is not due to any particular bias by the committee, but simply reflects the quality and the spectrum of the submissions we received.
Efficient Broadcasting in Known Geometric Radio Networks with Non-uniform Ranges
Authors: Leszek Gąsieniec, Dariusz R. Kowalski, Andrzej Lingas, Martin Wahlen
Venue: Proceedings of the 22nd international symposium on Distributed Computing (2008)

We study here deterministic broadcasting in geometric radio networks (GRN) whose nodes have complete knowledge of the network. Nodes of a GRN are deployed in the Euclidean plane (R 2) and each of them can transmit within some range r assigned to it. We adopt model in which ranges of nodes are non-uniform and they are drawn from the predefined interval 0 ≤ r min ≤ r max . All our results are in the conflict-embodied model where a receiving node must be in the range of exactly one transmitting node in order to receive the message.We derive several lower and upper bounds on the time of deterministic broadcasting in GRNs in terms of the number of nodes n, a distribution of nodes ranges, and the eccentricity D of the source node (i.e., the maximum length of a shortest directed path from the source node to another node in the network). In particular:(1) We show that D + ¿(log(n ¿ D)) rounds are required to accomplish broadcasting in some GRN where each node has the transmission range set either to 1 or to 0. We also prove that the bound D + ¿(log(n ¿ D)) is almost tight providing a broadcasting procedure that works in this type of GRN in time D + O(logn).(2) In GRNs with a wider choice of positive node ranges from r min , ...,r max , we show that broadcasting requires $D+\Omega (\min\{\log {\frac {r_{max}}{r_{min}}},\log (n-D)\})$ rounds and that it can be accomplished in $O (D\log^2 \frac {r_{max}} {r_{min}})$ rounds subsuming the best currently known upper bound $O (D (\frac {r_{max}} {r_{min}})^4)$ provided in [15].(3) We also study the problem of simulation of minimum energy broadcasting in arbitrary GRNs. We show that energy optimal broadcasting that can be completed in h rounds in a conflict-free model may require up to h/2 additional rounds in the conflict-embodied model. This lower bound should be seen as a separation result between conflict-free and conflict-embodied geometric radio networks. Finally, we also prove that any h-hop broadcasting algorithm with the energy consumption ${\cal E}$ in a GRN can be simulated within O(hlog¿) rounds in the conflict-embodied model using energy $O({\cal E})$, where ¿ is the ratio between the largest and the shortest Euclidean distance between a pair of nodes in the network.
A Methodological Approach for the Effective Modeling of Bayesian Networks
Authors: Martin Atzmueller, Florian Lemmerich
Venue: Proceedings of the 31st annual German conference on Advances in Artificial Intelligence (2008)

Modeling Bayesian networks manually is often a tedious task. This paper presents a methodological view onto the effective modeling of Bayesian networks. It features intuitive techniques that are especially suited for inexperienced users: We propose a process model for the modeling task, and discuss strategies for acquiring the network structure. Furthermore, we describe techniques for a simplified construction of the conditional probability tables using constraints and a novel extension of the Ranked-Nodes approach. The effectiveness and benefit of the presented approach is demonstrated by three case studies.
A graph based approach to estimating lexical cohesion
Authors: Hayrettin Gürkök, Murat Karamuftuoglu, Markus Schaal
Venue: Proceedings of the second international symposium on Information interaction in context (2008)

Traditionally, information retrieval systems rank documents according to the query terms they contain. However, even if a document may contain all query terms, this does not guarantee that it is relevant to the query. The query terms can occur together in the same document, but may have been used in different contexts, expressing separate topics. Lexical cohesion is a characteristic of natural language texts, which can be used to determine whether the query terms are used in the same context in the document. In this paper we make use of a graph-based approach to capture term contexts and estimate the level of lexical cohesion in a document. To evaluate the performance of our system, we compare it against two benchmark systems using three TREC document collections.