ppxscal/embedding_network huggingface dataset:
Teaching C++ in a multi-user virtual environment
Authors: J. Mark Pullen, Eugene Norris, Mark Fix
Venue: ACM SIGCSE Bulletin (2000)

The Internet has opened tremendous possibilities for distance education, where teachers and students can be distributed worldwide. However, much of today's Internet-based teaching is limited to student access of Web-based multimedia documents. In this paper we describe new dimensions in distributed education that are possible in synchronous sessions where the students interact with the teacher in real time. We review and elaborate on the nature of the MUVE, a spatially oriented, network-accessed software environment that uses persistent object technology to promote student creativity and allow continuity between online sessions. We describe our experiences in using a MUVE to enable distributed education at the college level in graduate and undergraduate courses, and its use with high school students in the DARPA Computer-Assisted Education and Training Initiative (CAETI).
A Parallel Adaptive Gauss-Jordan Algorithm
Authors: N. Melab, E.-G. Talbi, S. Petiton
Venue: The Journal of Supercomputing (2000)

This paper presents a parallel adaptive version of the block-based Gauss-Jordan algorithm, utilized to invert large matrices. This version includes a characterization of the workload and a mechanism of its folding/unfolding. Furthermore, this paper proposes a work scheduling strategy and an application-oriented solution for the fault tolerance problem. The application is implemented and experimented with MARS1 in dedicated and non-dedicated environments. The results show that an absolute efficiency of 92% is possible on a cluster of DEC/ALPHA processors interconnected by a Gigaswitch network and an absolute efficiency of 67% can be obtained on an Ethernet network of SUN-Sparc 4 workstations. Moreover, the algorithm is tested on a meta-system including both the two parks of machines. Finally, an out-of-core solution for the algorithm is proposed. This solution allows a gain of 66% of data input operations and reduces the central memory space required for storing the data space of the algorithm by a factor q, where q is the dimension of the matrix to be inverted in terms of data blocks.
Unsupervised Multiresolution Segmentation for Images with Low Depth of Field
Authors: James Z. Wang, Jia Li, Robert M. Gray, Gio Wiederhold
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2001)

Unsupervised segmentation of images with low depth of field (DOF) is highly useful in various applications including image enhancement for digital cameras, target recognition, image indexing for content-based retrieval, and 3D microscopic image analysis. This paper describes a novel multiresolution image segmentation algorithm for low DOF images. The algorithm is designed to separate a sharply focused object-of-interest from other foreground or background objects. The algorithm is fully automatic in that all parameters are image independent. A multiscale approach based on high frequency wavelet coefficients and their statistics is used to perform context-dependent classification of individual blocks of the image. Unlike other edge-based approaches, our algorithm does not rely on the process of connecting object boundaries. The algorithm has achieved high accuracy when tested on more than 100 low DOF images, many with inhomogeneous foreground or background distractions. Compared with the state of the art algorithms, this new algorithm provides better accuracy at higher speed.
Automatic information extraction from web pages
Authors: Budi Rahardjo, Roland H. C. Yap
Venue: Proceedings of the 24th annual international ACM SIGIR conference on Research and development in information retrieval (2001)

Many web pages have implicit structure. In this paper, we show the feasibility of automatically extracting data from web pages by using approximate matching techniques. This can be applied to generate automatic wrappers or to notify/display web page differences, web page change monitoring, etc.
Using meta-level compilation to check FLASH protocol code
Authors: Andy Chou, Benjamin Chelf, Dawson Engler, Mark Heinrich
Venue: ACM SIGPLAN Notices (2000)

Building systems such as OS kernels and embedded software is difficult. An important source of this difficulty is the numerous rules they must obey: interrupts cannot be disabled for "too long," global variables must be protected by locks, user pointers passed to OS code must be checked for safety before use, etc. A single violation can crash the system, yet typically these invariants are unchecked, existing only on paper or in the implementor's mind.This paper is a case study in how system implementors can use a new programming methodology, metalevel compilation (MC), to easily check such invariants. It focuses on using MC to check for errors in the code used to manage cache coherence on the FLASH shared memory multiprocessor. The only real practical method known for verifying such code is testing and simulation. We show that simple, system-specific checkers can dramatically improve this situation by statically pinpointing errors in the program source. These checkers can be written by implementors themselves and, by exploiting the system-specific information this allows, can detect errors unreachable with other methods. The checkers in this paper found 34 bugs in FLASH code despite the care used in building it and the years of testing it has undergone. Many of these errors fall in the worst category of systems bugs: those that show up sporadically only after days of continuous use. The case study is interesting because it shows that the MC approach finds serious errors in well-tested, non-toy systems code. Further, the code to find such bugs is usually 10-100 lines long, written in a few hours, and exactly locates errors that, if discovered during testing, would require several days of investigation by an experienced implementor.The paper presents 8 checkers we wrote, their application to five different protocol implementations, and a discussion of the errors that we found.
Post-layout transistor sizing for power reduction in cell-based design
Authors: Masanori Hashimoto, Hidetoshi Onodera
Venue: Proceedings of the 2001 Asia and South Pacific Design Automation Conference (2001)

We propose a transistor sizing method that down-sizes MOSFETs inside a cell to eliminate redundancy of cell-based circuits as much as possible. Our method reduces power dissipation of detail-routed circuits while preserving interconnects. The effectiveness of our method is experimentally evaluated using 5 circuits. The power dissipation is reduced by 77% maximum and 65% on average without delay increase.
Information scent as a driver of Web behavior graphs: results of a protocol analysis method for Web usability
Authors: Stuart K. Card, Peter Pirolli, Mija Van Der Wege, Julie B. Morrison, Robert W. Reeder, Pamela K. Schraedley, Jenea Boshart
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2001)

The purpose of this paper is to introduce a replicable WWW protocol analysis methodology illustrated by application to data collected in the laboratory. The methodology uses instrumentation to obtain detailed recordings of user actions with a browser, caches Web pages encoutered, and videotapes talk-aloud protocols. We apply the current form of the method to the analysis of eight Web protocols, visualizing the structure of the interaction and showing the strong effect of information scent in determining the path followed.
An indirect chaining method for addressing on secondary keys
Authors: L. R. Johnson
Venue: Communications of the ACM (1961)

Methods for entering random-access files on the basis of one key are briefly surveyed. The widely used chaining method, based on a pseudo-random key transformation, is reviewed in more detail. An efficient generalization of the chaining method which permits recovery on additional keys is then presented.
Simplification by Cooperating Decision Procedures
Authors: Greg Nelson, Derek C. Oppen
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1979)

A method for combining decision procedures for several theories into a single decision procedure for their combination is described, and a simplifier based on this method is discussed. The simplifier finds a normal form for any expression formed from individual variables, the usual Boolean connectives, the equality predicate =, the conditional function if-then-else, the integers, the arithmetic functions and predicates +, -, and &le;, the Lisp functions and predicates car, cdr, cons, and atom, the functions store and select for storing into and selecting from arrays, and uninterpreted function symbols. If the expression is a theorem it is simplified to the constant true, so the simplifier can be used as a decision procedure for the quantifier-free theory containing these functions and predicates. The simplifier is currently used in the Stanford Pascal Verifier.
Computing in the RAIN: A Reliable Array of Independent Nodes
Authors: Vasken Bohossian, Chenggong C. Fan, Paul S. LeMahieu, Marc D. Riedel, Jehoshua Bruck, Lihao Xu
Venue: IEEE Transactions on Parallel and Distributed Systems (2001)

The RAIN project is a research collaboration between Caltech and NASA-JPL on distributed computing and data storage systems for future spaceborne missions. The goal of the project is to identify and develop key building blocks for reliable distributed systems built with inexpensive off-the-shelf components. The RAIN platform consists of a heterogeneous cluster of computing and/or storage nodes connected via multiple interfaces to networks configured in fault-tolerant topologies. The RAIN software components run in conjunction with operating system services and standard network protocols. Through software-implemented fault tolerance, the system tolerates multiple node, link, and switch failures, with no single point of failure. The RAIN technology has been transfered to Rainfinity, a start-up company focusing on creating clustered solutions for improving the performance and availability of Internet data centers. In this paper, we describe the following contributions: 1) fault-tolerant interconnect topologies and communication protocols providing consistent error reporting of link failures, 2) fault management techniques based on group membership, and 3) data storage schemes based on computationally efficient error-control codes. We present several proof-of-concept applications: a highly-available video server, a highly-available Web server, and a distributed checkpointing system. Also, we describe a commercial product, Rainwall, built with the RAIN technology.
The multiple variable order problem for binary decision diagrams: theory and practical application
Authors: Christoph Scholl, Bernd Becker, Andreas Brogle
Venue: Proceedings of the 2001 Asia and South Pacific Design Automation Conference (2001)

Reduced Ordered Binary Decision Diagrams (ROBDDs) gained widespread use in logic design verification, test generation, fault simulation, and logic synthesis [17, 7]. Since the size of an ROBDD heavily depends on the variable order used, there is a strong need to find variable orders that minimize the number of nodes in an ROBDD. In certain applications we have to cope with ROBDDs with different variable orders, whereas further manipulations of these ROBDDs require common variable orders. In this paper we give a theoretical background for this "Multiple Variable Order problem". Moreover, we solve the problem to transform ROBDDs with different variable orders into a good common variable order using dynamic variable ordering techniques.
Global Context Recovery: A New Strategy for Syntactic Error Recovery by Table-Drive Parsers
Authors: Ajit B. Pai, Richard B. Kieburtz
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1980)

Described is a method for syntactic error recovery that is compatible with deterministic parsing methods and that is able to recover from many errors more quickly than do other schemes because it performs global context recovery. The method relies on fiducial symbols, which are typically reserved key words of a language, to provide mileposts for error recovery. The method has been applied to LL(1) parsers, for which a detailed algorithm is given, and informally proved correct. The algorithm will always recover and return control to the parser if the text being analyzed satisfies only minimal requirements: that it contains one or more occurrences of fiducial symbols following the point at which an error is detected. Tables needed for error recovery have been automatically generated, along with parsing tables, by a parser constructor for the LL(1) grammars. A theoretical characterization of fiducial symbols is given, and the utility of this characterization in practice is discussed. It has been applied to a grammar for the programming language Pascal to aid in selection of a set of fiducial symbols. The error recovery scheme has been tested on a set of student-written Pascal program texts and is compared with other error recovery strategies.
A diagnosis of beginning programmers' misconceptions of BASIC programming statements
Authors: Piraye Bayman, Richard E. Mayer
Venue: Communications of the ACM (1983)

In the process of learning a computer language, beginning programmers may develop mental models for the language. A mental model refers to the user's conception of the &ldquo;invisible&rdquo; information processing that occurs inside the computer between input and output. In this study, 30 undergraduate students learned BASIC through a self-paced, mastery manual and simultaneously had hands-on access to an Apple II computer. After instruction, the students were tested on their mental models for the execution of each of nine BASIC statements. The results show that beginning programmers&mdash;although able to perform adequately on mastery tests in program generation&mdash;possessed a wide range of misconceptions concerning the statements they had learned. This paper catalogs beginning programmers' conceptions of &ldquo;what goes on inside the computer&rdquo; for each of nine BASIC statements.
Multiparadigm design of a simple relational database
Authors: Charles D. Knutson, Timothy A. Budd, Hugh Vidos
Venue: ACM SIGPLAN Notices (2000)

Multiparadigm programming languages (such as Leda) seek to merge elements of several programming paradigms into a single cohesive language that utilizes programming and conceptual aspects from various paradigms (including imperative, object-oriented, functional and logic). While there are relatively few fully multiparadigm languages, most popular languages increasingly incorporate aspects from multiple paradigms. Despite the fact that multiparadigm programming is an increasing reality, there are few methods for multiparadigm design. This paper uses Leda to explore multiparadigm program design via a simple database example. This paper is exploratory in nature, and exposes areas that should be researched further.
Decomposability, instabilities, and saturation in multiprogramming systems
Authors: P. J. Courtois
Venue: Communications of the ACM (1975)

A step-by-step approach to model the dynamic behavior and evaluate the performance of computing systems is proposed. It is based on a technique of variable aggregation and the concept of nearly decomposable systems, both borrowed from Econometrics. This approach is taken in order to identify in multiprogramming paging systems (i) unstable regimes of operations and (ii) critical computing loads which bring the system into states of saturation. This analysis leads to a more complete definition of the circumstances in which &ldquo;thrashing&rdquo; can set in.
Using the Bedside Wellness System During Chemotherapy Decreases Fatigue and Emesis in Cancer Patients
Authors: Hiroshi Oyama, Mayumi Kaneda, Noriyuki Katsumata, Tatsuo Akechi, Mieko Ohsuga
Venue: Journal of Medical Systems (2000)

Background: The bedside wellness system (BSW) is effective for decreasing stress and improving mental well-being and should help relieve the side effects and mental disorders of patients during cancer chemotherapy. Methods: The study was a randomized clinical trial. After giving informed consent, patients were randomly assigned to the BSW intervention or control groups. The patients were given the Hospital Anxiety and Depression Scale (HADS) test before the trial to evaluate their emotional baseline. The Cancer Fatigue Scale, which was developed at our institute, and face visual analog scale were used to measure the emotional state and subjective feelings before and after the trial. The degree of emesis was measured using a visual analogue scale after the experience. We set up the system in a room in the outpatient clinic of the National Cancer Center New Hospital Building. Results: The decreases in the fatigue score and emesis score 3&ndash;5 days after chemotherapy were statistically significant (both p < 0.05) and carry-over effects were detected. Conclusions: BSW intervention therapy is an effective way to treat fatigue and emesis. This virtual reality system is a new therapeutic method that can be used in palliative medicine.
Balanced truncation with spectral shaping for RLC interconnects
Authors: Payam Heydari, Massoud Pedram
Venue: Proceedings of the 2001 Asia and South Pacific Design Automation Conference (2001)

This paper presents a numerically stable and efficient algorithm for model reduction of large RLC networks using frequency-weighted balanced truncation technique. The salient features of this algorithm include guaranteed stability of the reduced transfer function as well as availability of provable frequency-weighted error bounds. Such frequency weighting is essential to provide better control over time-domain error of the reduced system. The first k largest singular values of the system are obtained using the Lanczos algorithm, and the Lyapunov equations are solved by an iterative Lyapunov equation solver. Experimental results demonstrate the higher accuracy of our technique compared to Krylov-subspace-based model reduction techniques and other truncated balanced realizations that do not use spectral shaping. Based on MATLAB simulations, the run-time of our method is only 5% more than that of PRIMA.
Is the Pollution Effect of the FEM Avoidable for the Helmholtz Equation Considering High Wave Numbers?
Authors: Ivo M. Babuska, Stefan A. Sauter
Venue: SIAM Review (2000)

The development of numerical methods for solving the Helmholtz equation, which behaves robustly with respect to the wave number, is a topic of vivid research. It was observed that the solution of the Galerkin finite element method (FEM) differs significantly from the best approximation with increasing wave number. Many attempts have been presented in the literature to eliminate this lack of robustness by various modifications of the classical Galerkin FEM.However, we will prove that, in two and more space dimensions, it is impossible to eliminate this so-called pollution effect. In contrast, we will present a generalized FEM in one dimension that behaves robustly (i.e., is pollution-free) with respect to the wave number.The theory developed in this paper can also be used for the comparison of different discretization methods with respect to the size of their pollution.
A methodology for the evaluation of the replacement of information network technology with applications
Authors: Rafiq Jamal-Aldeen, Saad Haj Bakry, Adnan Nouh
Venue: International Journal of Network Management (2000)

A methodology for the evaluation of the replacement of one network technology by another is presented here. The methodology is based on technical evaluations associated with the network capacity on the one hand, and an economic evaluation concerned with its services on the other. An application of the methodology to a case study shows that ATM should replace the available conventional packet switching over 64&sim;kbps digital technology immediately. Copyright &copy; 2000 John Wiley Sons, Ltd.
Short circuit power estimation of static CMOS circuits
Authors: Seung-Ho Jung, Jong-Humn Baek, Seok-Yoon Kim
Venue: Proceedings of the 2001 Asia and South Pacific Design Automation Conference (2001)

This paper presents a simple method to estimate short-circuit power dissipation for static CMOS logic circuits. Short-circuit current expression is derived by accurately interpolating peak points of actual current curves which is influenced by the gate-to-drain coupling capacitance. It is shown through simulations that the proposed technique yields better accuracy than previous methods when signal transition time and/or load capacitance decreases, which is a characteristic of the present technological evolution.
Logic of English grammar
Authors: Herbert G. Bohnert
Venue: Communications of the ACM (1962)

The logic of English grammar is being investigated by a process of approximative logical synthesis. Beginning with a kernel language which is an alphabetically spelled form of symbolic logic with English-like vocabulary, English-like extensions are constructed simulating selected features of English grammar. For each extended language, an algorithm is given which would permit a computer to make a left-to-right, word-by-word scan of an input sequence, to transform it by stages (as long as the sequence is found to be a well-formed formula of the extended language) into a sentence in the logical grammar of the kernel (or into a logical symbolization if desired). The algorithm thus constitutes simultaneously (1) a recognition grammar of the extended language, i.e., not just formation rules or productions, but a decision method for sentencehood, and (2) a portion of its transformation rules (defining a consequence relation). To date, languages have been constructed simulating the English determiners, (e.g., &ldquo;every&rdquo;, &ldquo;any&rdquo;, &ldquo;no&rdquo;, &ldquo;a&rdquo;) and the system of groupers (&ldquo;either&rdquo;, &ldquo;both&rdquo;, &ldquo;if&rdquo;) with precedence-ordered connectives (e.g., &ldquo;and&rdquo;, &ldquo;and furthermore&rdquo;, &ldquo;or&rdquo;, &ldquo;or else&rdquo;) by which English achieves the effect of parentheses. Work soon to be reported extends the analysis to relative, general and indefinite pronouns. It is expected that the algorithms will be embodied in computer programs within the year for purposes of comparison with results of human parsers.
Introducing computing to smaller colleges and universities&mdash;a progress report
Authors: Louis T. Parker,  Jr., Thomas M. Gallie, Frederick P. Brooks, James K. Ferrell
Venue: Communications of the ACM (1969)

By technical means that are now routine, computer service for smaller colleges and universities can be provided by remote terminals of a central facility. Access, however, is not enough&mdash;effective organizational and educational methodology for introducing computing at such institutions must also be developed. The experience of two years with a statewide network involving 41 institutions is discussed. Lessons include the importance of a separate organization representing the small colleges, the necessity for on-campus training for the institutions, the need for some special programming and documentation to support such users, and the development of curriculum by evolutionary means.
Authentication of signatures using public key encryption
Authors: Kellogg S. Booth
Venue: Communications of the ACM (1981)

One of Needham and Schroeder's proposed signature authentication protocols is shown to fail when there is a possibility of compromised keys: this invalidates one of the applications of their technique. A more elaborate mechanism is proposed which does not require a network clock, but does require a third party to the transaction. The latter approach is shown to be reliable in a fairly strong sense.