ppxscal/embedding_network huggingface dataset:
Distributed design review in virtual environments
Authors: Mike Daily, Mike Howard, Jason Jerald, Craig Lee, Kevin Martin, Doug McInnes, Pete Tinker
Venue: Proceedings of the third international conference on Collaborative virtual environments (2000)

In large distributed corporations, distributed design review offers the potential for cost savings, reduced time to market, and improved efficiency. It also has the potential to improve the design process by enabling wider expertise to be incorporated in design reviews. This paper describes the integration of several components to enable distributed virtual design review in mixed multi-party, heterogeneous multi-site 2D and immersive 3D environments. The system provides higher layers of support for collaboration including avatars, high fidelity audio, and shared artifact manipulation. The system functions across several interface environments ranging from CAVEs to Walls to desktop workstations. At the center of the software architecture is the Human Integrating Virtual Environment (HIVE) [6], a collaboration infrastructure and toolset to support research and development of multi-user, geographically distributed, 2D and 3D shared applications. The HIVE functions with VisualEyes software for visualizing 3D data in virtual environments. We also describe in detail the configuration and lessons learned in a two site, heterogeneous multi-user demonstration of the system between HRL Laboratories in Malibu, California and GM R D in Warren, Michigan.
New Devices for 3D Pose Estimation: Mantis Eyes, Agam Paintings, Sundials, and Other Space Fiducials
Authors: Alfred M. Bruckstein, Robert J. Holt, Thomas S. Huang, Arun N. Netravali
Venue: International Journal of Computer Vision (2000)

Several unconventional ideas for viewer/camera pose estimation are discussed. The methods proposed so far advocate the use of advanced image processing for identification and precise location of calibration objects in the images acquired, and base pose recovery on the identification of the viewing dependent deformations of these objects. We propose to more fully exploit the freedom in the design of &ldquo;space fiducials&rdquo; or calibration objects showing that we can build objects whose images directly encode, in easily identifiable gray-level/color or temporal patterns, the pose of their viewer. We also show how to construct high-precision fiducials, which can determine a viewing direction quite accurately when it is known to lie within a relatively narrow range.
PIROL: a case study for multidimensional separation of concerns in software engineering environments
Authors: Stephan Herrmann, Mira Mezini
Venue: ACM SIGPLAN Notices (2000)

In this paper, we present our experience with applying multidimensional separation of concerns to a software engineering environment. By comparing two different designs of our system, we show the importance of separating integration issues from the implementation of the individual concerns. We present a model in which integration issues are encapsulated into rst--class connector objects and indicate how this facilitates the understandability, maintenance and evolution of the system. We identify issues of binding time, binding granularity and binding cardinality as important criteria in selecting an appropriate model for separation of concerns. We finally show how a good choice following these criteria and considering the requirements of software engineering environments leads to a system with dynamic configurability, high--level component integration and support for multiple instantiable views.
&ldquo;Saccade pickers&rdquo; vs. &ldquo;fixation pickers&rdquo;: the effect of eye tracking instrumentation on research
Authors: Keith S. Karn
Venue: Proceedings of the 2000 symposium on Eye tracking research & applications (2000)

Users of most video-based eye trackers apply proximity algorithms to identify fixations and assume that saccades are what happen in between. Most video-based eye trackers sample at 60 Hz., a rate which is too low to reliably find small saccades in an eye position record. We propose to call these slower eye trackers and their typical proximity analysis routines &ldquo;fixation pickers.&rdquo; Systems such as dual-Purkinje-image (DPI) trackers, coil systems, and electro-oculography permit higher sampling rates, typically providing the 250 Hz or greater sampling frequency necessary to detect most saccades. Researchers using these types of eye trackers typically focus on identifying saccades using velocity based algorithms and assume that fixations are what happen in between these movements. We propose to call these faster eye trackers and their velocity-based analysis routines &ldquo;saccade pickers.&rdquo; Given that fixation pickers and saccade pickers extract different things from an eye position record, it is no wonder that the two systems yield different results. This discrepancy has become a problem in eye movement research. A study of cognitive processing conducted with one eye tracking system is likely to give results which cannot be easily compared to a study conducted with another eye tracker. Imagine that two investigators are both interested in studying visual search. Both choose the number of saccades as one of their dependent variables to measure search performance. One investigator chooses a video-based fixation picker. The other investigator chooses a DPI-based saccade picker. Because the saccade picker is tuned to identify smaller saccades, the investigator with the DPI tracker reports more saccades and fixations during an equivalent visual search task compared to the investigator with the video-based tracker. Both investigations are likely to produce valid results, but results which are not comparable to the other investigator's.
Tracing the lineage of view data in a warehousing environment
Authors: Yingwei Cui, Jennifer Widom Janet L. Wiener
Venue: ACM Transactions on Database Systems (TODS) (2000)

We consider the view data lineageproblem in a warehousing environment: For a given data item in a materialized warehouse view, we want to identify the set of source data items that produced the view item. We formally define the lineage problem, develop lineage tracing algorithms for relational views with aggregation, and propose mechanisms for performing consistent lineage tracing in a multisource data warehousing environment. Our result can form the basis of a tool that allows analysts to browse warehouse data, select view tuples of interest, and then &ldquo;drill-through&rdquo; to examine the exact source tuples that produced the view tuples of interest.
A Proof System for Communicating Sequential Processes
Authors: Krzysztof R. Apt, Nissim Francez, Willem P. de Roever
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1980)

An axiomatic proof system is presented for proving partial correctness and absence of deadlock (and failure) of communicating sequential processes. The key (meta) rule introduces cooperation between proofs, a new concept needed to deal with proofs about synchronization by message passing. CSP's new convention for distributed termination of loops is dealt with. Applications of the method involve correctness proofs for two algorithms, one for distributed partitioning of sets, the other for distributed computation of the greatest common divisor of n numbers.
Programming language methods in computer security
Authors: John C. Mitchell
Venue: ACM SIGPLAN Notices (2001)

This invited talk will give a personal view of the field of computer security and summarize some ways that methods from the study of programming language principles can be applied to problems in computer security. Some background information is provided here in this short document.
Java-based mobile asset location
Authors: Luca Deri
Venue: Mobile Networks and Applications (2001)

Owing to the way networks grow and the advent of mobile computing, the task of physically locating assets is becoming increasingly complex. Network management tools are usually not suitable for management of dynamically moving assets and provide almost no facilities for asset localisation. In addition, asset management products delegate to human operators the task to identify physical asset's location. JLocator is a Java-based system that allows both static and dynamic assets to be physically localised. Based on SNMP and Java, it enables users to locate assets through a simple web interface and allows asset management systems to take advantage of asset location information provided by JLocator. Finally, its distributed architecture makes it scalable and completely platform-independent.
Teaching computer graphics visual literacy to art and computer science students: advantages, resources and opportunities
Authors: Dena Eber, Rosalee Wolfe
Venue: ACM SIGGRAPH Computer Graphics (2000)

Although it is a requisite skill for success in industry, visual literacy in graphics is intimidating to computer science and art students. Computer science majors are uneasy about using their eyes to examine images while art students may not have much background in the technical terminology. This column is the second in a two-part series that discusses an interdisciplinary teaching technique that overcomes these obstacles. Part one was published in Computer Graphics 34(1) February 2000, pp. 24-26. With this approach students become more familiar with the limits and possibilities of the medium of computer graphics, learn how to analyze and talk about what visual images might mean and develop a deeper understanding of time constraints. In addition, they gain confidence with technological terminology and the idea of suggesting alternative algorithms to create a desired visual "look." As a result both computer science and art students become more able to communicate effectively about and with visual imagery.
A compiler for analyzing cryptographic protocols using noninterference
Authors: Antonio Durante, Riccardo Focardi, Roberto Gorrieri
Venue: ACM Transactions on Software Engineering and Methodology (TOSEM) (2000)

The Security Process Algebra (SPA) is a CCS-like specification languag e where actions belong to two different levels of confidentiality. It has been used to define several noninterference-like security properties whose verification has been automated by the tool CoSeC. In recent years, a method for analyzing security protocols using SPA and CoSeC has been developed. Even if it has been useful in analyzing small security protocols, this method has shown to be error-prone, as it requires the protocol description and its environment to be written by hand. This problem has been solved by defining a protocol specification language more abstract than SPA, called VSP, and a compiler CVS that automatically generates the SPA specification for a given protocol described in VSP. The VSP/CVS technology is very powerful, and its usefulness is shown with some case studies: the Woo-Lam one-way authentication protocol, for which a new attack to authentication is found, and the Wide Mouthed Frog protocol, where different kinds of attack are detected and analyzed.
Mechanization of tedious algebra&mdash;the e coefficients of theoretical chemistry
Authors: H. D. Wactlar, M. P. Barnett
Venue: Communications of the ACM (1964)

A table of formulas for certain integrals involving Legendre functions has been constructed mechanically by a program which performed algebraic operations. The formulas are all rational algebraic expressions in a single variable and were constructed by a recurrence procedure. They are of interest in molecular quantum chemistry. Trivial coding techniques were used to write the relevant programs in FORTRAN. The results were photocomposed on a Photon S-560 system, that was controlled by tapes which were punched directly from the computer output, so avoiding manual keyboarding, transcription errors and keyboarded correction.
Computer pattern recognition techniques: electrocardiographic diagnosis
Authors: Lawrence Stark, Mitsuharu Okajima, Gerald H. Whipple
Venue: Communications of the ACM (1962)

The use of programmed digital computers as general pattern classification and recognition devices is one phase of the current lively interest in artificial intelligence. It is important to choose a class of signals which is, at present, undergoing a good deal of visual inspection by trained people for the purpose of pattern recognition. In this way comparisons between machine and human performance may be obtained. A practical result also serves as additional motivation. Clinical electrocardiograms make up such a class of signals. The approach to the problem presented here centers upon the use of multiple adaptive matched filters that classify normalized signals. The present report gives some of the background for the application of this method.
Minimal perfect hash functions made simple
Authors: Richard J. Cichelli
Venue: Communications of the ACM (1980)

A method is presented for computing machine independent, minimal perfect hash functions of the form: hash value &larr; key length + the associated value of the key's first character + the associated value of the key's last character. Such functions allow single probe retrieval from minimally sized tables of identifier lists. Application areas include table lookup for reserved words in compilers and filtering high frequency words in natural language processing. Functions for Pascal's reserved words, Pascal's predefined identifiers, frequently occurring English words, and month abbreviations are presented as examples.
Embodied interaction in social virtual environments
Authors: Elisabeth Cuddihy, Deborah Walters
Venue: Proceedings of the third international conference on Collaborative virtual environments (2000)

The interaction models found in typical desktop virtual environments designed for social interactions need to be improved in order to provide an adequate sense of embodiment and appropriate levels of abstraction for collaborative tasks. In order to improve the kinds of user interfaces available in social desktop virtual environments, new mechanisms for embodied interaction are needed. Such mechanisms would allow the dynamic generation of user interface displaying currently available high-level actions that can be performed on objects. This paper evaluates the kinds of interactions currently available in social desktop virtual environments, explores how these interactions effect the end-user experience, and suggests possible solutions for improving a user's sense of embodiment and presence in such environments.
Modeling and Performance Comparison of Reliability Strategies for Distributed Video Servers
Authors: Jamel Gafsi, Ernst W. Biersack
Venue: IEEE Transactions on Parallel and Distributed Systems (2000)

Large scale video servers are typically based on disk arrays that comprise multiple nodes and many hard disks. Due to the large number of components, disk arrays are susceptible to disk and node failures that can affect the server reliability. Therefore, fault tolerance must be already addressed in the design of the video server. For fault tolerance, we consider parity-based as well as mirroring-based techniques with various distribution granularities of the redundant data. We identify several reliability schemes and compare them in terms of the server reliability and per stream cost. To compute the server reliability, we use continuous time Markov chains that are evaluated using the SHARPE software package. Our study covers independent disk failures and dependent component failures. We propose a new mirroring scheme called Grouped One-to-One scheme that achieves the highest reliability among all schemes considered. The results of this paper indicate that dividing the server into independent groups achieves the best compromise between the server reliability and the cost per stream. We further find that the smaller the group size, the better the trade-off between a high server reliability and a low per stream cost.
MOSIX: A Cluster Load-Balancing Solution for Linux
Authors: Ibrahim F. Haddad, Evangeline Paquin
Venue: Linux Journal (2001)

A clustered Linux telecom-grade internet server.
Dynamic verification of operating system decisions
Authors: R. S. Fabry
Venue: Communications of the ACM (1973)

Dynamic verification of a decision implies that every time the decision is made there is a consistency check performed on the decision using independent hardware and software. The dynamic verification of operating system decisions is used on the PRIME system being designed and constructed at the University of California, Berkeley. PRIME is an experimental time-sharing system which is to have the properties of continuous availability, data privacy, and cost effectiveness. The technique of dynamic verification allows the construction of an operating system which does not make certain decisions improperly even in the presence of a single hardware or software fault. Furthermore, multiple faults lead to unreliable operation only if the faults happen to reinforce each other. On PRIME, dynamic verification is used to ensure that one user's information cannot become available to another user gratuitously even in the presence of a single hardware or software fault. The amount of additional hardware and software required for dynamic verification can be modest.
Real-Time Data Semantics and Similarity-Based Concurrency Control
Authors: Tei-Wei Kuo, Aloysius K. Mok
Venue: IEEE Transactions on Computers (2000)

This paper formalizes the concept of similarity which has been used on an ad hoc basis by application engineers to provide more flexibility in concurrency control. We show how the usual correctness criteria of concurrency control, namely, final-state, view, and conflict serializability, can be weakened to incorporate similarity. We extend the weakened correctness criteria in [16] for real-time applications which may run continually, have concurrent transaction executions, or skip unimportant computations. A semantic approach based on the similarity concept is then taken to propose a sufficient condition for scheduling real-time transactions without locking of data.
B-Spline Based, Large-Signal DC and Microwave-Model for SOI MOSFETs
Authors: Siraj Akhtar, Patrick Roblin
Venue: Analog Integrated Circuits and Signal Processing (2000)

We present a large/small-signal, non-quasi-static, charge conserving, SOI MOSFET modeling technique suitable for DC and high frequency circuit design. The device model is extracted from small signal microwave iso-thermal Y-parameter data and DC I&ndash;V characteristics. Low frequency dispersions associated with self-heating and floating body effects are verified to not limit the performance of this technique since it relies on both DC and transient I&ndash;V characteristics. The technique is applied to the modeling of a short-channel, partially depleted, SOI nMOSFET simulated on PISCES. The model generated is incorporated into a circuit simulator, which is used to perform large-signal transient and harmonic balance simulations. The transient I&ndash;V and gate charge extracted from the iso-thermal small-signal microwave Y-parameters, are in excellent agreement with the iso-thermal transient I&ndash;V and gate charge obtained from PISCES, respectively. The model topology is extended with a parasitic bipolar sub-circuit which automatically calculates the DC operating point for self-biasing circuits. Transient and non-linear power characterization results predicted with this model agree well with those obtained from PISCES for a wide range of input power drives. A complete electro-thermal model is proposed and verified to be able to predict temperature and transient I&ndash;V response.
Nerd Work: attractors and barriers perceived by students entering the IT field
Authors: Martha E. Myers, Catherine M. Beise
Venue: Proceedings of the 2001 ACM SIGCPR conference on Computer personnel research (2001)

The purpose of this study is to investigate the factors that attract as well as discourage students who display an initial interest in IT careers. Factors influencing students one way or the other may include media images of IT, role models, gender, and age. The study proposes to investigate these factors by focusing on the first programming course that is standard in many IT curricula. Demographic factors of students who enroll and either withdraw, pass, or fail the course will be analyzed, and then the same students will be surveyed to examine in greater depth their perceptions, both negative and positive, about IT careers and IT professionals. The results will provide educators and practitioners with information about myths that students hold that need to be dispelled, as well as the possible need to convey more realistic perspectives on the breadth and variety of IT jobs. Identification of these factors can help in recruiting as well as retaining a greater number of qualified students and ultimately increasing the supply of qualified IT workers.
How to share a secret
Authors: Adi Shamir
Venue: Communications of the ACM (1979)

In this paper we show how to divide data D into n pieces in such a way that D is easily reconstructable from any k pieces, but even complete knowledge of k - 1 pieces reveals absolutely no information about D. This technique enables the construction of robust key management schemes for cryptographic systems that can function securely and reliably even when misfortunes destroy half the pieces and security breaches expose all but one of the remaining pieces.
Telemedicine: challenges and opportunities
Authors: Sang-Goo Lee, Seong K. Mun, Prakash Jha, Betty A. Levine, Duk-Woo Ro
Venue: Journal of High Speed Networks (2000)

Telemedicine is many things to many people. Only until a few years ago, telemedicine was equated to video teleconferencing between physicians, while nowadays, perhaps the most active area in telemedicine is the store-and-forward model. There is a big shift from private and dedicated modes of communications to connectivity through the Internet. Presented is a collection of applications that provide snapshots of this diversity. The key technical challenges identified from these experiences are connectivity and integration. Also, at issue are the evolution process through which a telemedicine application evolves and the ability to choose the right set of technology for the diverse type of telemedicine applications. With the projected improvements in speed and quality of the Internet, wireless communication, and personal computational devices, it is expected that various concepts of telemedicine will develop into standard practices in tomorrows health care.
A Posteriori Error Estimators for a Class of Variational Inequalities
Authors: Wenbin Liu, Ningning Yan
Venue: Journal of Scientific Computing (2000)

In this paper, we present an a posteriori error analysis for the finite element approximation of a variational inequality. We derive a posteriori error estimators of residual type, which are shown to provide upper bounds on the discretization error for a class of variational inequalities provided the solutions are sufficiently regular. Furthermore we derive sharp a posteriori error estimators with both lower and upper error bounds for a subclass of the obstacle problem which are frequently met in many physical models. For sufficiently regular solutions, these estimates are shown to be equivalent to the discretization error in an energy type norm. Our numerical tests show that these sharp error estimators are both reliable and efficient in guiding mesh adaptivity for computing the free boundaries.