ppxscal/embedding_network huggingface dataset:
What is "next" in event processing?
Authors: Walker White, Mirek Riedewald, Johannes Gehrke, Alan Demers
Venue: Proceedings of the twenty-sixth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems (2007)

Event processing systems have wide applications ranging from managing events from RFID readers to monitoring RSS feeds. Consequently, there exists much work on them in the literature. The prevalent use of these systems is on-line recognition of patterns that are sequences of correlated events in event streams. Query semantics and implementation efficiency are inherently determined by the underlying temporal model: how events are sequenced (what is the "next" event), and how the time stamp of an event is represented. Many competing temporal models for event systems have been proposed, with no consensus on which approach is best. We take a foundational approach to this problem. We create a formal framework and present event system design choices as axioms. The axioms are grouped into standard axioms and desirable axioms. Standard axioms are common to the design of all event systems. Desirable axioms are not always satisfied, but are useful for achieving high performance. Given these axioms, we prove several important results. First, we show that there is a unique model up to isomorphism that satisfies the standard axioms and supports associativity, so our axioms are a sound and complete axiomatization of associative time stamps in eventsystems. This model requires time stamps with unbounded representations. We present a slightly weakened version of associativity that permits a temporal model with bounded representations. We show that adding the boundedness condition also results in a unique model, so again our axiomatization is sound and complete. We believe this model is ideally suited to be the standard temporal model for complex event processing.
Objecting to objects
Authors: Stephen C. Johnson
Venue: Proceedings of the USENIX Winter 1994 Technical Conference on USENIX Winter 1994 Technical Conference (1994)

Object Oriented Programming (OOP) is currently being hyped as the best way to do everything from promoting code reuse to forming lasting relationships with persons of your preferred sexual orientation. This paper tries to demystify the benefits of OOP. We point out that, as with so many previous software engineering fads, the biggest gains in using OOP result from applying principles that are older than, and largely independent of, OOP. Moreover, many of the claimed benefits are either not true or true only by chance, while occasioning some high costs that are rarely discussed. Most seriously, all the hype is preventing progress in tackling problems that are both more important and harder: control of parallel and distributed applications, GUI design and implementation, fault tolerant and real-time programming. OOP has little to offer these areas. Fundamentally, you get good software by thinking about it, designing it well, implementing it carefully, and testing it intelligently, not by mindlessly using an expensive mechanical process.
Adapting COTS Applications: an Experience Report
Authors: Robert Balzer, Alexander Egyed, Neil Goldman, Tim Hollebeek, Marcelo Tallis, David Wile
Venue: Proceedings of the 29th International Conference on Software Engineering Workshops (2007)

Over the last ten years, we have gained considerable experience with adapting COTS products to act variously as interfaces to problem-specific functionality and to provide such functionality itself. Several experimental implementations were based on a tool called the Briefing Associate that augmented Microsoft's PowerPoint to support the authoring of semantically grounded applications. Others were based on other Microsoft Office products, such as Access and Excel, and yet others were based on modeling tools such as IBM Rational Rose or Mathwork's MatLab. This report both gives a feeling for how applications can be augmented with such COTS interfaces and also discusses some of the problems that anyone adapting COTS tools is certain to face.
CyberBridges A Model Collaboration Infrastructure for e-Science
Authors: Heidi L. Alvarez, David Chatfield, Donald A. Cox, Eric Crumpler, Cassian D'Cunha, Ronald Gutierrez, Julio Ibarra, Eric Johnson, Kuldeep Kumar, Tom Milledge, Giri Narasimhan, S. Masoud Sadjadi, Chi Zhang
Venue: Proceedings of the Seventh IEEE International Symposium on Cluster Computing and the Grid (2007)

The "CyberBridges pilot project is an innovative model for creating a new generation of scientists and engineers who are capable of fully integrating cyberinfrastructure into the whole educational, professional, and creative process of their respective disciplines. CyberBridges augments graduate student education to include a foundation of understanding in Advanced Networking and Grid Infrastructure for High Performance Computing, and bridges the divide between the information technology community and diverse science and engineering disciplines. We demonstrate the effectiveness of CyberBridges by providing four case studies. Groundwork has begun to extend the outreach of CyberBridges for international research and education collaborations.
Thermal and mechanical simulation of bulk resonators
Authors: M. Morata, E. Figueras, I. Gracia, L. Fonseca, C. Cane
Venue: Proceedings of the Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (2003)

In this work, a mechanical silicon resonator fabricated on Silicon On Insulator (SOI) substrates, is simulated using ANSYS. Two different models are used depending on the objectives of the simulation. A 2D model is used for simulating the resonance frequency and the surface temperature distribution, as long as a 3-D model is necessary for more accurate thermal and stress-distribution analysis. Simple structures as cantilevers have been fabricated with different dimensions and preliminary results of the modal behaviour have been performed. As an example, fundamental modes around 3 kHz to 99 kHz and quality factors around 63 up to 1200 have been measured on structures of 1000/spl times/1000 /spl mu/m/sup 2/ and 300/spl times/300 /spl mu/m/sup 2/.
Dimensional reduction of 3D building models using graph theory and its application in building energy simulation
Authors: Christoph van Treeck, Ernst Rank
Venue: Engineering with Computers (2007)

Since the various people involved in the design process for a building project tend to hold conflicting views, this inevitably leads to a range of disparate models for planning and calculation purposes. In order to interpret the relevant geometrical, topological and semantical data for any given building model, we identify a structural component graph, a graph of room faces, a room graph and a relational object graph as aids and explain algorithms to derive these relations. We start with a building model by transferring its geometrical, topological and semantical data into a volume model, decomposing the latter into a so-called connection model and then extracting all air volume bodies and hulls of the model by means of further decomposition into elementary cyclic connection components. The technique is demonstrated within the scope of building energy simulation by deriving both a dimensionally reduced object model required for setting up a thermal multizone model and a geometrical model for defining single or multiple computational fluid dynamic domains in a building together with incidence matrices correlating these models. The algorithm is basically applicable to any building energy simulation tool.
A fuzzy perceptual model for map building and navigation of mobile robots
Authors: Eugenio Aguirre, José F. Argudo, Antonio González, Raúl Pérez
Venue: Integrated Computer-Aided Engineering (2004)

In the area of the intelligent mobile robots the hybrid reactive-deliberative architectures for navigation are aimed at an efficient integration of reactive and deliberative skills. Reactive skills allow the robot a fast reaction to unexpected events whereas deliberative skills permit the generation of plans to carry out tasks. In these systems a high level of accuracy in the modeling of the environment is not usually necessary but some representation structure is needed to generate safe paths for the robot navigation. Thus, the perception of the environment and the construction of useful models are two main problems to deal with. In this work, we propose a fuzzy perceptual model and a map building process which would allow us to build a world topological map giving us the possibility for reasoning and planning about the robot motion in the world. The perceptual model deals with the uncertainty and vagueness underlying the sensor data, it carries out the data fusion from different sensors and it allows us to establish various levels of interpretation in the sensor data. The topological map is used to generate high-level abstraction paths and then the navigation is carried out using our own hybrid architecture and taking into account the perceptual model to represent the robot's beliefs about the world. Experiments in simulation and in real office-like environments are shown for validating the proposal.
Local polynomial periodograms for signals with the time-varying frequency and amplitude
Authors: V. Katkovnik
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 03 (1996)

The estimation of the time-varying IF /spl Omega/(t) and amplitude A(t) of harmonic signals is considered. The nonparametric local polynomial approximation (LPA) is used in order to develop two new estimators, which enable one to estimate /spl Omega/(t), /spl Omega//sup (1)/(t), ..., /spl Omega/((m/sub /spl omega//-1))(t) and A(t), A/sup (1)/(t), ..., A((m/sub A/))(t), where m/sub /spl omega// and m/sub A/ are the degrees of the LPA of the phase and the amplitude. The a priori amplitude information about /spl Omega/(t), A(t) and their derivatives can be incorporated in order to improve the estimates. The estimators of the IF and the amplitude have forms of generalized periodograms and Fourier transforms respectively, where a polynomial function appears in the degree of the complex exponent usual for the Fourier transform. The asymptotic bias and covariance are obtained for the new estimators. In particular, it is shown that one of the new estimators ensures complete compensation of the disturbing influence of the time-varying amplitude for the estimation of the IF and vice versa.
Scalable kernel performance for internet servers under realistic loads
Authors: Gaurav Banga, Jeffrey C. Mogul
Venue: Proceedings of the annual conference on USENIX Annual Technical Conference (1998)

UNIX Internet servers with an event-driven architecture often perform poorly under real workloads, even if they perform well under laboratory benchmarking conditions. We investigated the poor performance of event-driven servers. We found that the delays typical in wide-area networks cause busy servers to manage a large number of simultaneous connections. We also observed that the select system call implementation in most UNIX kernels scales poorly with the number of connections being managed by a process. The UNIX algorithm for allocating file descriptors also scales poorly. These algorithmic problems lead directly to the poor performance of event-driven servers. We implemented scalable versions of the select system call and the descriptor allocation algorithm. This led to an improvement of up to 58% in Web proxy and Web server throughput, and dramatically improved the scalability of the system.
Gazing with pEYE: new concepts in eye typing
Authors: Anke Huckauf, Mario Urbina
Venue: Proceedings of the 4th symposium on Applied perception in graphics and visualization (2007)

Eye typing applications like a virtual keyboard are often straining to use. We developed various interfaces based on different theoretical ideas. In Iwrite, letters are selected by gazing towards the outer frame of the monitor. This should minimize the error rate, but to the disadvantage of speed. In a dynamic concept, StarWrite, moving letters are to be dragged directly onto the text window. The third implementation pEYEwrite is based on marking or pie menus which have already been shown to be powerful tools in mouse control. Preliminary testings demonstrated a superiority of pEYEwrite over the other concepts. Not only did pEYEwrite produce the fastest text entry, but also the largest increases in performance over several sessions. Data indicate that pie menus must be regarded as a helpful and powerful tool in various gaze control applications.
Vaulted VPN: compartmented virtual private networks on trusted operating systems
Authors: Tse-Huong Choo
Venue: Proceedings of the 8th conference on USENIX Security Symposium - Volume 8 (1999)

Virtual Private Networks for IPSec based on an intermediate packet-redirector in network-protocol stacks are becoming increasingly common for many standard operating systems and represent a well-understood method for retro-fitting such systems with IPSec support. This report describes how a different design structured around a Trusted Operating System can offer better security, performance and robustness. We describe in detail an implementation of an IPSec VPN consisting of a series of compartmented, concurrently executing IPSec stacks. The motivations and security-related benefits behind each design decision are discussed. In addition, we show how a configuration of independent IPSec stacks based on this design can be configured to execute in parallel for greater performance on single-threaded kernels, and how its design allows individual component-failures without affecting the system as a whole.
Knowledge-based Platform for Environmental Risk Management
Authors: Ladislav Hluchy, Ondrej Habala, Marian Babik, Michal Laclavik, Zoltan Balogh, Emil Gatial
Venue: Proceedings of the Sixth International Symposium on Parallel and Distributed Computing (2007)

We present a system for semantically-aided workflow management for SOA-based grid environment. The user can construct workflows of grid and web services just by stating the intended result, can see the workflow and its dynamic behavior in a graphical form, and can annotate the whole workflow, its parts, or its results. User experience, constructed workflows, and computed results can be shared between users. The system uses monitoring information to adapt to changes in the underlying infrastructure by extracting ontologically managed information about existing application services. One of its important features is also a transparency of the grid, and resulting ease of use even for application area experts not familiar with grid computing concepts. We also present the way this system is employed to predict flood hazards, using a series of simulation models for meteorology, hydrology, and hydraulics. The system is the result of the IST project K-Wf Grid.
Asymptotic Gauss--Jacobi quadrature error estimation for Schwarz--Christoffel integrals
Authors: David M. Hough
Venue: Journal of Approximation Theory (2007)

Numerical conformal mapping packages based on the Schwarz-Christoffel formula have been in existence for a number of years. Various authors, for good reasons of practical efficiency, have chosen to use composite n-point Gauss-Jacobi rules for the estimation of the Schwarz-Christoffel path integrals. These implementations rely on an ad hoc, but experimentally well-founded, heuristic for selecting the spacing of the integration end-points relative to the position of the nearby integrand singularities. In the present paper we derive an explicitly computable estimate, asymptotic as n->~, for the relevant Gauss-Jacobi quadrature error. A numerical example illustrates the potential accuracy of the estimate even at low values of n. It is apparent that the error estimate will allow the adaptive construction of composite rules in a manner that is more efficient than has been possible hitherto.
A Novel Distributed Topology Control Algorithm for Ad Hoc Networks
Authors: Peng He, Jiandong Li, Wei Dong
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 02 (2007)

Topology control for ad hoc networks aims to increase effective network capacity and conserve energy. In this paper we proposed a distributed topology control algorithm for ad hoc networks with directional antennas. The topology is controlled not only by adjusting the transmission powers of nodes but also by changing the antenna's pattern (direction). A node grows its transmission power until it finds some neighbor nodes in every sector of its directional antenna. We also employ two planarized optimizations that further reduce some redundant edges and make the topology as a planar graph eventually. The resulting network topology increases network lifetime by reducing transmission power and decreases traffic interference by having low node degrees. Simulation results demonstrate the effectiveness of the proposed algorithm.
Master's Degree in Digital Forensics
Authors: Philip Craiger, Lucille Ponte, Carrie Whitcomb, Mark Pollitt, Ronald Eaglin
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

Law enforcement agents at the local, state, and Federal levels have informed us of backlogs of computer-related crime cases ranging from 18 months to three years. The primary cause of these backlogs is the lack of educated and trained personnel to serve as digital forensics examiners. In response to this need, the University of Central Florida has created a Masters in Digital Forensics. This 30-hour degree is an interdisciplinary mix of technical, legal, ethical, and courtroom testimony-based courses. Students must complete a capstone course as well as a graduate internship to demonstrate proficiency in the knowledge and skills acquired from the courses.
A Policy Language for the Extended Reference Monitor in Trusted Operating Systems
Authors: Hyung Chan Kim, R. S. Ramakrishna, Wook Shin, Kouichi Sakurai
Venue: Proceedings of the The Second International Conference on Availability, Reliability and Security (2007)

The main focus of current research in Trusted Operating Systems (TOS) is on the enhanced access control of reference monitors which, in turn, control the individual operations on a given access instance. However, many real-life runtime attacks involve behavioral semantics. We have proposed an extended reference monitor to support both access and behavior controls. This results in a sequence of operations which are also of concern in security enforcement. This paper presents a policy language for the extended reference monitor. Our policy language is based on Domain and Type Enforcement (DTE) and Role-Based Access Control (RBAC). Permission is defined as an event and a state of behavior is represented as a fluent to be accorded with the convention of Event Calculus (EC). Behavior policies can be expressed with the EC style syntax as well as access control policies.
A convolutive source separation method with self-optimizing non-linearities
Authors: N. Charkani
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 05 (1999)

This paper deals with the separation of two convolutively mixed signals. The proposed approach uses a recurrent structure adapted by a generic rule involving arbitrary separating functions. These functions should ideally be set so as to minimize the asymptotic error variance of the structure. However, these optimal functions are often unknown in practice. The proposed alternative is based on a self-adaptive (sub-)optimization of the separating functions, performed by estimating the projection of the optimal functions on a predefined set of elementary functions. The equilibrium and stability conditions of this rule and its asymptotic error variance are studied. Simulations are performed for real mixtures of speech signals. They show that the proposed approach yields much better performance than classical rules.
Experiences with GroupLens: marking usenet useful again
Authors: Bradley N. Miller, John T. Riedl, Joseph A. Konstan
Venue: Proceedings of the annual conference on USENIX Annual Technical Conference (1997)

Collaborative filetering attempts to alleviate information overload by offering recommendations on whether information is valuable based on the opinions of those who have already evaluated it. Usenet news is an information source whose value is being severely diminished by the volume of low-quality and uninteresting information posted in its newsgroups. The GroupLens system applies collaborative filtering to Usenet news to demonstrate how we can restore the value of Usenet news by sharing our judgements of articles, with our identities protected by pseudonyms. This paper extends the original GroupLens work by reporting on a significantly enhanced system and the results of a seven week trial with 250 users and over 20,000 news articles. GroupLens has an open and flexible architecture that allows easy integration of new newsreader clients and ratings bureaus. We show ratings and prediction profiles for three news-groups, and assess the accuracy of the predictions.
Quantifying the Value of Visual and Haptic Position Feedback During Force-Based Motion Control
Authors: Katherine J. Kuchenbecker, Netta Gurari, Allison M. Okamura
Venue: Proceedings of the Second Joint EuroHaptics Conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (2007)

Controlling the motion of a prosthetic upper limb without visual feedback is extremely difficult because the wearer does not know the prosthesis' configuration. This paper describes an experiment designed to determine the relative importance of visual and haptic position feedback during targeted force-based motion by non-amputee human subjects as an analogy to prosthetic use. Subjects control the angle of a virtual proxy through an admittance relationship by generating torque at the MCP joint of the right index finger. During successive repetitions of a target acquisition task, the proxy's state is selectively conveyed to the user through graphical display, finger motion, and tactile stimulation. Performance metrics for each feedback condition will provide insights on the role of haptic position feedback and may help guide the development of future upper-limb prostheses.
Developing Linux software for fun turns into profit
Authors: Jo-Ellen Jo-Ellen, Mark Mathews
Venue: Proceedings of the 3rd annual conference on Atlanta Linux Showcase - Volume 3 (1999)

For the small, software company or individual consultant, there is an overpowering concern with regard to Linux development: investment pay off?". In the case of Absolute Value Software, the answer to that question is a resounding YES!
Learning styles and personality types of computer science students at a South African university
Authors: Vashti C. Galpin, Ian D. Sanders, Pei-yu Chen
Venue: ACM SIGCSE Bulletin (2007)

This research investigates the learning styles and personality types of Computer Science students at the University of the Witwatersrand in Johannesburg, South Africa using the Kolb Learning Style Inventory and the Keirsey Temperament Sorter, respectively. Students were found to be predominantly abstract intheir learning, and they did not show strong preferences on the reflective/active dimension hence they had either a Converger or Assimilator learning style which is consistent with prior research. Across the three years of undergraduate study, learning styles became more balanced in terms of the reflective/activedimension. Students were predominantly ISTJ, ISFJ, ESTJ or ESFJ in their personality types showing a strong presence of the SJ temperament which is associated with organisation, planning and decision-making. This result is less consistent with prior research. There were no significant differences over the three years in personality type.