ppxscal/embedding_network huggingface dataset:
Efficient importance sampling for ML estimation of SCD models
Authors: L. Bauwens, F. Galli
Venue: Computational Statistics Data Analysis (2009)

The evaluation of the likelihood function of the stochastic conditional duration (SCD) model requires to compute an integral that has the dimension of the sample size. ML estimation based on the efficient importance sampling (EIS) method is developed for computing this integral and compared with QML estimation based on the Kalman filter. Based on Monte Carlo experiments, EIS-ML estimation is found to be more precise statistically, but involves an acceptable loss of quickness of computations. The method is illustrated with real data and is shown to be easily applicable to extensions of the SCD model.
Software Test Design Through Behavioral Modeling
Authors: Shel Prince
Venue:  (2008)

Author Shel Prince presents a groundbreaking methodology for software-testing design that assures fewer bugs and thoroughly tested software applications in less time, and with less hassle, than traditional methods. The breakthrough involves Behavioral Modeling, a technique that produces the minimum size test suite for the maximum testing coverage. Addressing the three biggest problems facing anyone responsible for testing softwaretime constraints, too many bugs, and inadequate requirementsauthor Prince offers systematic and concrete solutions to these problems providing a scalable, actionable approach valid in an enterprise or boutique development environment. Sure to become a classic in the world of software testing best practices, Software Test Design through Behavioral Modeling removes the guesswork from test suite design and empowers end-users, developers, testers and project managers with the tools they need to move their projects into go-live status with confidence.
Design considerations for a heterogeneous tightly-coupled multiprocessor system
Authors: Kenichiro Noguchi, Isao Ohnishi, Hiroshi Morita
Venue: Proceedings of the May 19-22, 1975, national computer conference and exposition (1975)

In a multiprocessor system, processors share main memory and a single copy of the operating system in shared main memory controls the entire system. Basically each processor can execute, any of the programs in the system. (This type of multiprocessor system is sometimes called a tightly-coupled multiprocessor system to distinguish from another type of multiprocessor system in which each processor has its own main memory and operating system. In this paper a "multiprocessor system" means a "tightly-coupled multiprocessor system" unless otherwise noted.) A multiprocessor system usually consists of identical processors, which have same computing speeds as well as the same functional characteristics. In this paper a more general type of multiprocessor system which consists of processors of different computing speeds are discussed. The component processors are equivalent in the hardware functions but have different performance characteristics. This type of multiprocessor system, a heterogeneous multiprocessor system, has the following merits as compared with a homogeneous multiprocessor.
Particle-based fluid flow visualization on meshes
Authors: Khalid Djado, Richard Egli
Venue: Proceedings of the 6th International Conference on Computer Graphics, Virtual Reality, Visualisation and Interaction in Africa (2009)

This paper presents a new method for animating particles on an arbitrary triangular mesh starting from a fluid flow velocity field. The velocity field visualization with particles allows for the production of new special effects. An attraction constraint is introduced to correct a particle's velocity so its trajectory remains near the surface. A repulsion constraint is also used to ensure a better distribution of particles on the surface. Our velocity field is obtained by physically-based heuristics, implemented with a chain model. Our method is robust and yields good results, in particular for interactive simulations, even for systems with several thousand particles.
First workshop on transforming and weaving ontologies in model driven engineering (TWOMDE 2008)
Authors: Fernando Silva Parreiras, Jeff Z Pan, Uwe Assmann, Jakob Herinksson
Venue: ACM SIGMOD Record (2009)

The First International Workshop on Transforming and Weaving Ontologies in Model Driven Engineering (TWOMDE 2008), affiliated with the 11th International Conference on Model Driven Engineering Languages and Systems (MoD-ELS2008), brought together researchers and practitioners from the modeling community with experience or interest in MDE and in Knowledge Representation to discuss about: (1) how the scientific and technical results around ontologies, ontology languages and their corresponding reasoning technologies can be used fruitfully in MDE; (2) the role of ontologies in supporting model transformation; (3) and how ontologies can improve designing domain specific languages.
Where is social informatics?
Authors: Alexander Halavais
Venue: ACM SIGCAS Computers and Society (2004)

The term "social informatics," at least among those who work in one or more of the various fields it helps to unite, unavoidably elicits its originator and greatest advocate, Rob Kling. Kling coined the term in order to help describe a perspective in which information technologies were studied within their social contexts. It was also used to describe a new interdiscipline, one that drew computer science and the social sciences closer together, and that recognized a literature at this nexus as an emergent, cohesive whole. Kling answered the question "What is social informatics?" explicitly not only in widely read articles on the topic, but in public talks and private conversations. As the idea of social informatics has become more widely known, another question follows it: where is social informatics? Has it made an imprint on scholarly institutions? 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
A Reputation-Based Trust Evaluation Model for P2P E-Commerce
Authors: Wang Liang, Guo Yajun, Qi Mei
Venue: International Journal of Distributed Sensor Networks (2009)

P2P e-commerce as a new shopping pattern is developing rapidly, and users can transact with anybody anytime and anywhere in the P2P e-commerce system, but as users often interact with strangers, hence building trust among the users, make the users know each other well, estimate the risk of participating in a transaction, and enable to transact securely in the P2P e-commerce system is an urgent problem to be solved for P2P e-commerce nowadays. In order to settle the problem, this paper provides a novel reputation-based trust model in P2P e-commerce system. The main thought of the proposed trust model is that a node has two types of reputation: local reputation and global reputation. In the local reputation computing, we take the calculation of factors including the amount of transaction money and transaction time and so on, and in the global reputation computing, there are three factors introduced—the number of neighbor nodes, the direct trust level of neighbor nodes, and the trust evaluation weight of neighbor nodes, and finally the object node's trust level can be obtained by using the local reputation weight coefficient and the global reputation weight coefficient to integrate the node's local reputation with global reputation. We have conducted two experiments that show that our trust model contrast with the present typical trust models EigenRep and Beta in the aspects of the computing load and the successful transaction rate. The first experiment shows that the trust model has a lower computing load compared to the EigenRep and Beta, because we do not compute the node's reputation through the transitive recommending of the intermediate nodes; the second experiment shows that the trust model has a higher successful transaction rate when the malicious nodes exist in the system, and even the number of malicious nodes proportion is larger, the trust model also has a higher successful transaction rate. In conclusion, the trust model more roundly takes into account the factors affecting the local reputation and global reputation and can greatly improve their computing methods. The experiment results show that the trust model can reduce the trust level computing load, and have more improvements on the successful transaction rate and anti-attack capability compared to the existing trust models. But the trust model does not introduce the risk factor, and the logic of the trust mode is relatively simple, so our trust model still needs to be improved constantly.
Mechanical and thermal properties of poly(urethane urea) nanocomposites prepared with diamine-modified Laponite
Authors: Joe-Lahai Sormana, Santanu Chattopadhyay, J. Carson Meredith
Venue: Journal of Nanomaterials (2008)

Nanocomposites based on segmented poly(urethane urea) were prepared by reacting a poly(diisocyanate) with diamine-modified Laponite-RD nanoparticles that served as a chain extender. The nanocomposites were prepared at a constant NH2 to NCO mole ratio of 0.95, while varying the fraction of diamine-modified Laponite relative to the free diamine chain extender. Compared to neat poly(urethane urea), all nanocomposites showed increased tensile strength and elongation at break. As Laponite loading increased, tensile properties passed through a maximum at a particle concentration of 1 mass%, at which a 300% increase in tensile strength and 40% increase in elongation at break were observed. A maximum in urea and urethane hard-domain melting endotherms was also observed at this Laponite loading. Optimal mechanical and thermal properties coincided with a minimum in the size of the inorganic Laponite phase. Nanocomposites containing diamine-modified Laponite had higher tensile strengths than those with nonreactive monoamine-modified Laponite or diamine-modified Cloisite.
Audience identification for end user documentation
Authors: Janis G. Raymond
Venue: Proceedings of the June 7-10, 1982, national computer conference (1982)

Audience identification in writing is comparable to the analysis phase of systems development. Understanding who the users will be, what their business function is and how it relates to the computer system, and what the users need to know is the only way to write effective user documentation. Identifying the users determines the type and amount of detail to include as well as the format, tone, and level of the documentation. Audience identification is the planning phase of the documentation and as such controls the entire writing process. This paper presents guidelines for identifying end users and directing the documentation to their needs. 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
Demo CD "Relationship", a Demonstration
Authors: Franz Witzeling
Venue: Proceedings of the 1999 IEEE International Conference on Multimedia Computing and Systems - Volume 02 (1999)

The project consists of different parts: In "cyber office" a psychotherapeutic praxis is simulated where the "cyber client" uses through choosing different forms of new communication tools unconsciously the possibility of free projection. In "relationship" we offer a realistic life-scenario (ship tour) where the user plays a role game and has to solve different situations of conflict and communication.
Designing and managing an SNA network for growth
Authors: S. M. Schiffman
Venue: Proceedings of the May 16-19, 1983, national computer conference (1983)

The IBM Information Network is a nationwide System Network Architecture (SNA) network that offers network services and application offerings to end users. This paper describes the techniques used to design and manage the growth of the network. Emphasis is placed on the design process and the migration and implementation plans to expand the network while still providing 24-hour operation 7 days a week. Areas covered include adding processors, bandwidth, multiplexers, and end user devices.
Upper and Lower Bounds on Black-Box Steganography
Authors: Nenad Dedi&#x0107;, Gene Itkis, Leonid Reyzin, Scott Russell
Venue: Journal of Cryptology (2009)

We study the limitations of steganography when the sender is not using any properties of the underlying channel beyond its entropy and the ability to sample from it. On the negative side, we show that the number of samples the sender must obtain from the channel is exponential in the rate of the stegosystem. On the positive side, we present the first secret-key stegosystem that essentially matches this lower bound regardless of the entropy of the underlying channel. Furthermore, for high-entropy channels, we present the first secret-key stegosystem that matches this lower bound statelessly (i.e., without requiring synchronized state between sender and receiver).
A query processor for prediction-based monitoring of data streams
Authors: Sergio Ilarri, Ouri Wolfson, Eduardo Mena, Arantza Illarramendi, Prasad Sistla
Venue: Proceedings of the 12th International Conference on Extending Database Technology: Advances in Database Technology (2009)

Networks of sensors are used in many different fields, from industrial applications to surveillance applications. A common feature of these applications is the necessity of a monitoring infrastructure that analyzes a large number of data streams and outputs values that satisfy certain constraints. In this paper, we present a query processor for monitoring queries in a network of sensors with prediction functions. Sensors communicate their values according to a threshold policy, and the proposed query processor leverages prediction functions to compare tuples efficiently and to generate answers even in the absence of new incoming tuples. Two types of constraints are managed by the query processor: window-join constraints and value constraints. Uncertainty issues are considered to assign probabilistic values to the results returned to the user. Moreover, we have developed an appropriate buffer management strategy, that takes into account the contributions of the prediction functions contained in the tuples. We also present some experimental results that show the benefits of the proposal.
Flexible calling context reification for aspect-oriented programming
Authors: Alex Villazon, Walter Binder, Philippe Moret
Venue: Proceedings of the 8th ACM international conference on Aspect-oriented software development (2009)

Aspect-oriented programming (AOP) eases the development of profilers, debuggers, and reverse engineering tools. Such tools frequently rely on calling context information. However, current AOP technology, such as AspectJ, does not offer dedicated support for accessing complete calling context within aspects. In this paper, we introduce a novel approach to calling context reification that reconciles flexibility, efficiency, accuracy, and portability. It relies on a generic bytecode instrumentation framework ensuring complete bytecode coverage, including the standard Java class library. We compose our program transformations for calling context reification with the AspectJ weaver, providing the aspect developer an efficient mechanism to manipulate a customizable representation of the complete calling context. To highlight the benefits of our approach, we present ReCrash as an aspect using a stack-based calling context representation; ReCrash is an existing tool that generates unit tests to reproduce program failures. In comparison with the original ReCrash tool, our aspect resolves several limitations, is extensible, covers also the standard Java class library, and causes less overhead.
The Beowulf Analysis Symbolic INterface: Interactive Parallel Data Analysis for Everyone
Authors: Enrico Vesperini, David M. Goldberg, Stephen L. W. McMillan, James Dura, Douglas Jones
Venue: Computing in Science and Engineering (2009)

The advent of affordable parallel computers such as Beowulf PC clusters and, more recently, multicore PCs has been highly beneficial for a large number of scientists and smaller institutions that might not otherwise have access to substantial computing facilities. However, there hasn't been an analogous progress in the development and dissemination of parallel software—scientists need the expertise to develop parallel codes and must invest a significant amount of time in the development of tools even for the most common data-analysis tasks. The authors describe the Beowulf Analysis Symbolic INterface (BASIN), a multiuser parallel data analysis and visualization framework. BASIN is aimed at providing scientists with a suite of parallel libraries for astrophysical data analysis along with general tools for data distribution and parallel operations on distributed data that lets them easily develop new parallel libraries for their specific tasks.
Modeling and Simulation of Freeway Short-Term Traffic Flow Prediction
Authors: Chai Gan, Zhu Canghui
Venue: Proceedings of the 2009 International Conference on Advanced Computer Control (2009)

Freeway short-term traffic flow prediction can lay a solid foundation for analyzing the road traffic operation status and making real-time traffic surveillance strategies. Firstly, because of the complex modeling process and off-line prediction, differential method together with zero equalization in the data pretreatment and recursive least square method with forgetting factors in the parameter identification are used in establishing improved time-series prediction model. Secondly, as the difficulty in determining the initial value, the statistical method is used to generate initial value in modeling of Kalman filtering prediction model. Thirdly, because of the low speed of convergence in the BP neural network and the local minimum problem existing in the BP algorithm, RBF neural network is used in establishing the traffic volume prediction model. The results indicate that predictability of various models is confirmed, and the characteristic of individual models is also obtained.
Improving patient flow in a hospital emergency department
Authors: D. J. Medeiros, Eric Swenson, Christopher DeFlitch
Venue: Proceedings of the 40th Conference on Winter Simulation (2008)

Hospital emergency departments in the US are facing increasing challenges due to growth in patient demand for their services, and inability to increase capacity to match demand. We report on a new approach to patient flow in emergency departments, and a simulation model of the approach. Initial results from the model show that the approach is feasible, and a pilot study demonstrates substantial improvements in patient care.
Extraordinary computing: religion as a lens for reconsidering the home
Authors: Susan P. Wyche, Rebecca E. Griner
Venue: Proceedings of the 27th international conference on Human factors in computing systems (2009)

We present results from a study examining how American Protestant Christians' faith affects their domestic life. There are two contributions of this work for the HCI community. First, we provide empirical evidence demonstrating how topics of interest to HCI researchers (e.g., material artifacts, routines, and ICT use) are used for religious purposes. Our findings show how Christians distinguish these aspects of domestic life from their secular counterparts. Second, we use our findings to reflect on current directions of future domestic ICT applications. Specifically, we critically evaluate the "problem solving approaches dominating the design of future technologies, and present extraordinary computing or systems that promote and honor the special value accorded to some aspects of domestic life.
Straight-Line Grid Drawings of Label-Constrained Outerplanar Graphs with O(n logn) Area (Extended Abstract)
Authors: Md. Rezaul Karim, Md. Jawaherul Alam, Md. Saidur Rahman
Venue: Proceedings of the 3rd International Workshop on Algorithms and Computation (2009)

A straight-line grid drawing of a planar graph G is a drawing of G on an integer grid such that each vertex is drawn as a grid point and each edge is drawn as a straight-line segment without edge crossings. Any outerplanar graph of n vertices with the maximum degree d has a straight-line grid drawing with area O(dn logn). In this paper, we introduce a subclass of outerplanar graphs, which we call label-constrained outerplanar graphs, that admits straight-line grid drawings with O(n logn) area. We give a linear-time algorithm to find such a drawing. We also give a linear-time algorithm for recognition of label-constrained outerplanar graphs.
An educational project for master's program in computing
Authors: Juliana Peneva, Stanislav Ivanov, Petko Staynov
Venue: Proceedings of the 9th International Conference on Computer Systems and Technologies and Workshop for PhD Students in Computing (2008)

The curriculum of a specific master's program is discussed in thematic and methodological aspect. The general plan, the target group and the educational parameters of the program are represented. The features of the curriculum as thematic areas, learning activities and schedule are discussed. Some statistical data concerning the program implementation are also provided.
A MAC protocol for low-rate UWB wireless sensor networks using directional antennas
Authors: Eirini Karapistoli, Ioannis Gragopoulos, Ioannis Tsetsinas, Fotini-Niovi Pavlidou
Venue: Computer Networks: The International Journal of Computer and Telecommunications Networking (2009)

Ultra-wideband (UWB) is a key solution for wireless connectivity, characterized by ultralow power consumption and a good degree of robustness to interference and multipath fading. Evidence of its significance, is its recent use in the IEEE 802.15.4a standard. UWB technology with joint consideration of directional antennas can benefit when compared to classical omni-directional antennas from the energy conservation viewpoint, which is of fundamental concern when it comes to wireless sensor networks (WSNs). However, exploiting directionality requires new approach in the design of a medium access control (MAC) protocol to be applied. In this work, idle nodes continuously rotate their receiving beams over 360^o until a predefined preamble trailer is detected. The resulting scheme is a directional ultra-wideband MAC protocol, named DU-MAC, which deals effectively with the problem of deafness and the problem of determination of neighbors' location. Simulation-based studies will demonstrate the effectiveness of the proposed protocol in many critical parameters, such as throughput and network lifetime.
Framework for Illumination Invariant Vehicular Traffic Density Estimation
Authors: Pranam Janney, Glenn Geers
Venue: Proceedings of the 3rd Pacific Rim Symposium on Advances in Image and Video Technology (2009)

CCTV cameras are becoming a common fixture at the roadside. Their use varies from traffic monitoring to security surveillance. In this paper a novel technique, using Invariant Features of Local Textures (IFLT) Support Vector Machine (SVM), for estimating vehicular traffic density on a road segment is presented. The proposed approach is computationally efficient and robust to varying illumination. Experimental results have shown that the proposed framework can achieve high performance than extant state-of-the-art techniques in varying illumination conditions.