ppxscal/embedding_network huggingface dataset:
Modelling Real P2P Networks: The Effect of Altruism
Authors: Dimitrios K. Vassilakis, Vasilis Vassalos
Venue: Proceedings of the Seventh IEEE International Conference on Peer-to-Peer Computing (2007)

We develop a model of the interaction of rational peers in an incentive-free Peer-to-Peer (P2P) network and use game theoretic analysis to derive results about peer and network behavior. We calculate and discuss Nash equilibria and predict peer behavior in terms of individual contribution. At the heart of our model is altruism, an intrinsic parameter reflecting peers inherent willingness to contribute. Two different approaches for modelling altruistic behavior and its attendant benefit are introduced and discussed. We consider the cases of P2P networks of peers that (i) have homogeneous altruism levels or (ii) have heterogeneous altruism levels, but with known probability distributions. We find that, under the effects of altruism, a substantial fraction of peers will contribute when altruism levels are within certain intervals, even though no incentive mechanism is used. Our results corroborate empirical evidence of large P2P networks surviving or even flourishing without or with barely functioning incentive mechanisms.
Alternative proof and interpretations for a recent state-dependent importance sampling scheme
Authors: Pieter-Tjerk Boer, Werner R. Scheinhardt
Venue: Queueing Systems: Theory and Applications (2007)

Recently, a state-dependent change of measure for simulating overflows in the two-node tandem queue was proposed by Dupuis et al. (Ann. Appl. Probab. 17(4):1306---1346, 2007), together with a proof of its asymptotic optimality. In the present paper, we present an alternative, shorter and simpler proof. As a side result, we obtain interpretations for several of the quantities involved in the change of measure in terms of likelihood ratios.
Well-posedness for equilibrium problems and for optimization problems with equilibrium constraints
Authors: Ya-Ping Fang, Rong Hu, Nan-Jing Huang
Venue: Computers Mathematics with Applications (2008)

In this paper we generalize the concepts of well-posedness to equilibrium problems and to optimization problems with equilibrium constraints. We establish some metric characterizations of well-posedness for equilibrium problems and for optimization problems with equilibrium constraints. We prove that under suitable conditions, the well-posedness is equivalent to the existence and uniqueness of solutions. The corresponding concepts of well-posedness in the generalized sense are also introduced and investigated for equilibrium problems and for optimization problems with equilibrium constraints.
Performance Evaluation of TD-Learning Methods for Bandwidth Provisioning
Authors: M. Jahanshahi, M. R. Meybodi
Venue: Proceedings of the 7th IEEE International Conference on Computer and Information Technology (2007)

Q-learning and SARSA are two methods of TD- learning. Researchers interested in this field proposed the Eligibility concept in order to speed up Q-learning and SARSA. They proved their claim by running the algorithms in a static environment. Authors of this paper have used Q-learning, SARSA and also their eligibility versions for bandwidth provisioning in DiffServ networks that is an absolutely dynamic environment. Performance of these methods in this absolutely dynamic environment is evaluated. Keyword - Queuing delay guarantee, Bandwidth provisioning, DiffServ architecture, TD-learning
The Evolution of Peripheral Devices in Microprocessor Systems
Authors: K. McKenzie
Venue: Computer (1978)

LSI I/O controllers solve system problems by efficiently interfacing the microcomputer to external units. 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
The Architectural Elements of a Symmetric Fault-Tolerant Multiprocessor
Authors: A. L. Hopkins
Venue: IEEE Transactions on Computers (1975)

A hybrid-redundant multiprocessor is proposed in which each processing unit and each memory module is triplicated for purposes of error detection and momentary error masking Reconfiguration allows spare units to replace failed units and allows surviving units to regroup after spares have been exhausted. An arbitrary number of processing units and memory modules can be accommodated. A hybrid-redundant bus system interconnects the processors and memories, where the initial redundancy of the buses is a design parameter. A specialized circuit called a bus guardian unit (BGU) is employed in numerous places to control reconfiguration and testing in such a way as to eliminate susceptibility to failure events that occur in one module at a time. Considerable emphasis is placed on dynamic testing. This approach is briefly compared to other fault-tolerant computer systems.
Effect of plasma treatments on interface chemistry and adhesion strength between porous SiO2 low-k film and SiC/SiN layers
Authors: Shou-Yi Chang, Yi-Chung Huang
Venue: Microelectronic Engineering (2008)

In this study, the interface chemistry and adhesion strengths between porous SiO"2 low-dielectric-constant film and SiN capping layer as well as SiC etch stop layer have been investigated under different plasma treatments. Elements of Si, O, and N constructed an interlayer region with mixing Si-N and Si-O bonds at the interface between the porous SiO"2 film and SiN capping layer. After plasma treatments especially O"2 plasma, the oxygen content at the interface increased, and the binding energy obviously shifted to a higher level. Under nanoindentation and nanoscratch tests, interface delamination occurred, and the interface adhesion strength was accordingly measured. After plasma treatments especially the O"2 plasma, more Si-O bonds of high binding energy existed at the interface, and thus the interface adhesion strength was effectively improved. The adhesion energy of SiO"2/SiN and SiC/SiO"2 interfaces was enhanced to 4.7 and 10.5J/m^2 measured by nanoindentation test, and to 1.3 and 2.0J/m^2 by nanoscratch test, respectively.
Virtual worlds: multi-disciplinary research opportunities
Authors: David A. Bray, Benn R. Konsynski
Venue: ACM SIGMIS Database (2007)

Virtual worlds are now a reality, representing intriguing environments for researchers from multiple fields to pursue collaborative investigations. To provide a background, we first highlight the basic business and sociological phenomena occurring in virtual worlds. Real world institutions, ranging from business to governmental organizations, are already experiencing the effects of increased growth in the number of individuals participating in these virtual world environments. We consider research paths from four representative perspectives: (1) information systems, (2) neurobiology, (3) political science, and (4) organizational governance research. Virtual world environments offer significant opportunities for research in many fields for study, including demonstration and examination of intra-world and inter-world practice and behavior.
Fix IT-business relationships through better decision rights
Authors: Varun Grover, Raymond M. Henry, Jason B. Thatcher
Venue: Communications of the ACM (2007)

"The perils of screwing up (with technology) are greater every year, making the stakes for effective communication even higher."---Stan Lepeak, VP of technology research services at MetaGroup.
Synchronization medium: a consistency maintenance component for mobile multiplayer games
Authors: Abdul Malik Khan, Sophie Chabridon, Antoine Beugnard
Venue: Proceedings of the 6th ACM SIGCOMM workshop on Network and system support for games (2007)

In multiplayer games, where many players take part in a game while communicating through a network, the players may have an inconsistent view of the game world because of the communication delays across the network. This problem of inconsistency is even more crucial when playing on a mobile phone via a 3G network where the communication delays can be of several seconds. Consistency maintenance algorithms must be used to have a uniform view of the game world. These algorithms are very complex and hard to program. In this paper, we discuss different consistency maintenance algorithms from the point of view of mobile devices and present an approach where the consistency concern is handled separately by a distributed component called synchronization medium, which is responsible for communication as well as consistency maintenance. The game logic components interact with the synchronization medium to communicate between them and synchronize their data. We argue that this separation of concerns reduces the burden on the game developer. Moreover, a medium offers a generic interface and is designed to be easily reused for different game applications. Finally, using a medium, different consistency maintenance approaches can be tested and compared easily for experimentation.
Suggestions on Pattern Transformation in UML-RT
Authors: Yifeng Sun, David Levy
Venue: Proceedings of the International Conference on Software Engineering Advances (2007)

The capsule-centric object-oriented (OO) UML-RT framework is being widely applied in modeling large-scale complex systems. Like general UML, it is important to have software patterns to cope with the complexity in the software structure and the constant changes in requirements. However, there are not yet adequate and explicit discussions on the application of software patterns in UML-RT, and it is difficult and unnecessary to develop UML-RT patterns from the scratch. In this paper, we present some suggestions to transform the widely used UML design patterns into UML-RT compliant patterns while keeping as much of the applicability, functionality and flexibility of the original patterns as possible.
Interfaces for musical activities and interfaces for musicians are not the same: the case for codes, a web-based environment for cooperative music prototyping
Authors: Evandro Manara Miletto, Luciano Vargas Flores, Marcelo Soares Pimenta, Jérôme Rutily, Leonardo Santagada
Venue: Proceedings of the 9th international conference on Multimodal interfaces (2007)

In this paper, some requirements of user interfaces for musical activities are investigated and discussed, particularly focusing on the necessary distinction between interfaces for musical activities and interfaces for musicians. We also discuss the interactive and cooperative aspects of music creation activities in CODES, a Web-based environment for cooperative music prototyping, designed mainly for novices in music. Aspects related to interaction flexibility and usability are presented, as well as features to support manipulation of complex musical information, cooperative activities and group awareness, which allow users to understand the actions and decisions of all group members cooperating and sharing a music prototype.
Iterative OFDM ARQ Receivers with Imbedded Pilots
Authors: Thomas Ketseoglou
Venue: Proceedings of the Third IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (2007)

An optimized Automatic Repeat Request (ARQ) iterative receiver for Orthogonal Frequency Division Multiplexing (OFDM) transmission, suitable for application in rapidly varying multipath channels is presented. The receiver is an optimized Maximum Aposteriori (MAP) Turbo proces- sor that exploits information from all available transmis- sions. The system uses an imbedded pilot structure in the frequency domain to initially estimate the channel. Further improvement of these estimates takes place based on the Expectation Maximization (EM) algorithm and the avail- able received vectors, including all antennas and transmis- sions of the OFDM word. We show that this configuration achieves high gains compared to a standard ARQ system with packet combining and a standard soft decision decod- ing of a higher constraint length, = 7 convolutional code when binary modulation is employed on the link, while the gains diminish for non-binary modulations.
JADE: A software framework for developing multi-agent applications. Lessons learned
Authors: Fabio Bellifemine, Giovanni Caire, Agostino Poggi, Giovanni Rimassa
Venue: Information and Software Technology (2008)

Since a number of years agent technology is considered one of the most innovative technologies for the development of distributed software systems. While not yet a mainstream approach in software engineering at large, a lot of work on agent technology has been done, many research results and applications have been presented, and some software products exists which have moved from the research community to the industrial community. One of these is JADE, a software framework that facilitates development of interoperable intelligent multi-agent systems and that is distributed under an Open Source License. JADE is a very mature product, used by a heterogeneous community of users both in research activities and in industrial applications. This paper presents JADE and its technological components together with a discussion of the possible reasons for its success and lessons learned from the somewhat detached perspective possible nine years after its inception.
OLAP over imprecise data with domain constraints
Authors: Doug Burdick, AnHai Doan, Raghu Ramakrishnan, Shivakumar Vaithyanathan
Venue: Proceedings of the 33rd international conference on Very large data bases (2007)

Several recent papers have focused on OLAP over imprecise data, where each fact can be a region, instead of a point, in a multi-dimensional space. They have provided a multiple-world semantics for such data, and developed efficient ways to answer OLAP aggregation queries over the imprecise facts. These solutions, however, assume that the imprecise facts can be interpreted independently of one another, a key assumption that is often violated in practice. Indeed, imprecise facts in real-world applications are often correlated, and such correlations can be captured as domain integrity constraints (e.g., repairs with the same customer names and models took place in the same city, or a text span can refer to a person or a city, but not both). In this paper we provide a framework for answering OLAP aggregation queries over imprecise data in the presence of such domain constraints. We first describe a relatively simple yet powerful constraint language, and formalize what it means to take into account such constraints in query answering. Next, we prove that OLAP queries can be answered efficiently given a database D* of fact marginals. We then exploit the regularities in the constraint space (captured in a constraint hypergraph) and the fact space to efficiently construct D*. We present extensive experiments over real-world and synthetic data to demonstrate the effectiveness of our approach.
Note: Robust information clustering incorporating spatial information for breast mass detection in digitized mammograms
Authors: Aize Cao, Qing Song, Xulei Yang
Venue: Computer Vision and Image Understanding (2008)

In this paper, we investigate a robust information clustering (RIC) algorithm incorporating spatial information for breast mass detection in digitized mammograms. The detection system employs RIC algorithm based on the raw region of interest (ROI) extracted from global mammogram by two steps of adaptive thresholding. Pixels on the fuzzy margin of a mass and noisy data were identified by RIC through the minimax optimization of mutual information. The memberships of the identified pixels (outliers) were recalculated by incorporating spatial distance information that takes into account of the influence of a neighborhood of 3x3 window. The algorithm is robust in the sense that both peak and valley of image intensity histogram are estimated and the pixels corresponding to valley in the histogram are clustered adaptively to image content. The purpose of the detection system is to locate the suspicious regions of mass candidates in the mammograms which will be further examined by other diagnostic techniques or by radiologists. The proposed method has been verified with 60 mammograms in the MiniMIAS database. The experimental results show that the detection system has a sensitivity of 90.7% at 2.57 false positives (FPs) per image.
External perfect hashing for very large key sets
Authors: Fabiano C. Botelho, Nivio Ziviani
Venue: Proceedings of the sixteenth ACM conference on Conference on information and knowledge management (2007)

We present a simple and efficient external perfect hashing scheme (referred to as EPH algorithm) for very large static key sets. We use a number of techniques from the literature to obtain a novel scheme that is theoretically well-understood and at the same time achieves an order-of-magnitude increase in the size of the problem to be solved compared to previous "practical" methods. We demonstrate the scalability of our algorithm by constructing minimum perfect hash functions for a set of 1.024 billion URLs from the World Wide Web of average length 64 characters in approximately 62 minutes, using a commodity PC. Our scheme produces minimal perfect hash functions using approximately 3.8 bits per key. For perfect hash functions in the range {0,...,2n - 1} the space usage drops to approximately 2.7 bits per key. The main contribution is the first algorithm that has experimentally proven practicality for sets in the order of billions of keys and has time and space usage carefully analyzed without unrealistic assumptions.
Concept and architecture of a centaur robot
Authors: Satoshi Tsuda, Kuniya Shinozaki, Ryohei Nakatsu
Venue: Proceedings of the 2nd international conference on Digital interactive media in entertainment and arts (2007)

Recently various types of robots are being studied and developed, which can be classified into two groups: humanoid types and animal types. Since each group has its own merits and demerits, a new type of robot is expected to emerge with greater strengths and fewer weaknesses. In this paper we propose a new type of robot called the "Centaur Robot" by merging the concepts of these two types of robots. This robot has a human-like upper body and a four-legged animal-like lower body. Due to this basic architecture, the robot has several merits, including human-like behaviors. It can also walk smoothly and stably even on non-smooth ground. We describe the basic concept of our centaur robot and then explain its hardware and software architectures as well as its merits.
Genetic programming for computational pharmacokinetics in drug discovery and development
Authors: Francesco Archetti, Stefano Lanzeni, Enza Messina, Leonardo Vanneschi
Venue: Genetic Programming and Evolvable Machines (2007)

The success of a drug treatment is strongly correlated with the ability of a molecule to reach its target in the patient's organism without inducing toxic effects. Moreover the reduction of cost and time associated with drug discovery and development is becoming a crucial requirement for pharmaceutical industry. Therefore computational methods allowing reliable predictions of newly synthesized compounds properties are of outmost relevance. In this paper we discuss the role of genetic programming in predictive pharmacokinetics, considering the estimation of adsorption, distribution, metabolism, excretion and toxicity processes (ADMET) that a drug undergoes into the patient's organism. We compare genetic programming with other well known machine learning techniques according to their ability to predict oral bioavailability (%F), median oral lethal dose (LD50) and plasma-protein binding levels (%PPB). Since these parameters respectively characterize the percentage of initial drug dose that effectively reaches the systemic blood circulation, the harmful effects and the distribution into the organism of a drug, they are essential for the selection of potentially good molecules. Our results suggest that genetic programming is a valuable technique for predicting pharmacokinetics parameters, both from the point of view of the accuracy and of the generalization ability.
Image-based Visual Servoing with Central Catadioptric Cameras
Authors: Gian Luca Mariottini, Domenico Prattichizzo
Venue: International Journal of Robotics Research (2008)

This paper presents an image-based visual servoing strategy for the autonomous navigation of a mobile holonomic robot from a current towards a desired pose, specified only through a current and a desired image acquired by the on-board central catadioptric camera. This kind of vision sensor combines lenses and mirrors to enlarge the field of view. The proposed visual servoing does not require any metrical information about the three-dimensional viewed scene and is mainly based on a novel geometrical property, the auto-epipolar condition, which occurs when two catadioptric views (current and desired) undergo a pure translation. This condition can be detected in real time in the image domain by observing when a set of so-called disparity conics have a common intersection. The auto-epipolar condition and the pixel distances between the current and target image features are used to design the image-based control law. Lyapunov-based stability analysis and simulation results demonstrate the parametric robustness of the proposed method. Experimental results are presented to show the applicability of our visual servoing in a real context.
Lightweight State Based Mutation Testing for Security
Authors: Songtao Zhang, Thomas Dean, Scott Knight
Venue: Proceedings of the Testing: Academic and Industrial Conference Practice and Research Techniques - MUTATION (2007)

State based protocols are protocols in which the handling of one message depends on the contents of previous messages. Testing such protocols, for security or for other purposes usually means specifying the state space of the protocol in some manner. This paper introduces a novel method of using an existing client to explore the state space. The messages exchanged between the client and test system are captured and mutated. To send the mutated test messages, the previous messages must be resent. Constraints expressed in an extended version of the Semantic Constraint Language are used to automatically derive the data dependencies between the messages.
A Basis for the Quantitative Comparison of Computer Number Systems
Authors: Shauchi Ong
Venue: IEEE Transactions on Computers (1983)

This paper describes aspects of an arithmetic design system (ADS) to support the quantitative evaluation of alternate number systems with respect to a given application and realization technology. In computer arithmetic we are concerned with establishing a correspondence between abstract quantities (numbers) and some physical representation (symbols), and with simulating the operations on these symbols. The ADS is intended to help study the cost and performance of alternate simulations. A finite number system is a triple consisting of a symbol set (elements are called "digit-vectors"), an interpretation set, a mapping between these two sets, and a set of operators (digit-vector algorithms) defined on its symbol set. A set of these digit vector algorithms are proposed for conducting arithmetic design. A number system matrix defines the digit vector algorithm for numerous number systems and a method for computing time and space complexity of compositions of these algorithms is proposed. An example of how the system could be used to compare addition, with and without out-of-range detection, for three number systems is given.