Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- Information dissemination (4)
- Online systems (4)
- Document storage (3)
- Information systems (3)
- Algorithms (2)
-
- Information retrieval (2)
- Learning systems (2)
- Least squares approximations (2)
- Neural networks (2)
- Recursive functions (2)
- Technology transfer (2)
- World Wide Web (2)
- 5 Y (1)
- Allocation (1)
- Artificial Neural Network Classification (1)
- Artificial intelligence (1)
- Automated Cancer Detection (1)
- Backpropagation (1)
- Benign Tumors (1)
- Client server systems (1)
- Color Images (1)
- Computer information security (1)
- Computer science (1)
- Computing (1)
- Constraint database (1)
- Constraint object (1)
- Convergence of numerical methods (1)
- Cutting force identification (1)
- Deadliest Skin Cancer Form (1)
- Discriminant Features (1)
- Publication
Articles 1 - 30 of 53
Full-Text Articles in Engineering
The Fat-Pyramid And Universal Parallel Computation Independent Of Wire Delay, Ronald I. Greenberg
The Fat-Pyramid And Universal Parallel Computation Independent Of Wire Delay, Ronald I. Greenberg
Computer Science: Faculty Publications and Other Works
This paper shows that a fat-pyramid of area Θ(A) requires only O(log A) slowdown to simulate any competing network of area A under very general conditions. The result holds regardless of the processor size (amount of attached memory) and number of processors in the competing networks as long as the limitation on total area is met. Furthermore, the result is valid regardless of the relationship between wire length and wire delay. We especially focus on elimination of the common simplifying assumption that unit time suffices to traverse a wire regardless of its length, since the assumption becomes more and more …
Objects To The Rescue! Or Httpd: The Next Generation Operating System, Andrew P. Black, Jonathan Walpole
Objects To The Rescue! Or Httpd: The Next Generation Operating System, Andrew P. Black, Jonathan Walpole
Computer Science Faculty Publications and Presentations
This position paper suggests that object-oriented operating systems may provide the means to meet the ever-growing demands of applications. As an example of a successful OOOS, we cite the http daemon. To support the contention that httpd is in fact an operating system, we observe that it implements uniform naming, persistent objects and an invocation meta-protocol, specifies and implements some useful objects, and provides a framework for extensibility.We also believe that the modularity that is characteristic of OO systems should provide a performance benefit rather than a penalty. Our ongoing work in the Synthetix project at OGI is exploring the …
Optimum Symbol-By-Symbol Detection Of Uncoded Digital Data Over The Gaussian Channel With Unknown Carrier Phase, Pooi Yuen Kam, Seng Siew Ng, Tock Soon Ng
Optimum Symbol-By-Symbol Detection Of Uncoded Digital Data Over The Gaussian Channel With Unknown Carrier Phase, Pooi Yuen Kam, Seng Siew Ng, Tock Soon Ng
Research Collection School Of Computing and Information Systems
A theory of optimum receiver design for symbol-by-symbol detection of an uncoded digital data sequence received over the Gaussian channel with unknown carrier phase is presented. Linear suppressed-carrier modulation is assumed. The work here aims at laying a conceptual foundation for optimum symbol-by-symbol detection, and rectifies existing approaches to the problem. The optimum receiver structure is obtained explicitly for an arbitrary carrier phase model, but its computational requirements are too heavy in general for any practical implementation. In one important special case, namely, the case in which the carrier phase can be treated as a constant over some K+1 symbol …
Automated Manpower Rostering: Techniques And Experience, C. M. Khoong, Hoong Chuin Lau, L. W. Chew
Automated Manpower Rostering: Techniques And Experience, C. M. Khoong, Hoong Chuin Lau, L. W. Chew
Research Collection School Of Computing and Information Systems
We present ROMAN, a comprehensive, generic manpower rostering toolkit that successfully handles a wide spectrum of work policies found in service organizations. We review the use of various techniques and methodologies in the toolkit that contribute to its robustness and efficiency, and relate experience gained in addressing manpower rostering problems in industry.
Identification Of Cutting Force In End Milling Operations Using Recurrent Neural Networks, Q. Xu, K. Krishnamurthy, Bruce M. Mcmillin, Wen Feng Lu
Identification Of Cutting Force In End Milling Operations Using Recurrent Neural Networks, Q. Xu, K. Krishnamurthy, Bruce M. Mcmillin, Wen Feng Lu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The problem of identifying the cutting force in end milling operations is considered in this study. Recurrent neural networks are used here and are trained using a recursive least squares training algorithm. Training results for data obtained from a SAJO 3-axis vertical milling machine for steady slot cuts are presented. The results show that a recurrent neural network can learn the functional relationship between the feed rate and steady-state average resultant cutting force very well. Furthermore, results for the Mackey-Glass time series prediction problem are presented to illustrate the faster learning capability of the neural network scheme presented here
A Recursive Least Squares Training Algorithm For Multilayer Recurrent Neural Networks, Q. Xu, K. Krishnamurthy, Bruce M. Mcmillin, Wen Feng Lu
A Recursive Least Squares Training Algorithm For Multilayer Recurrent Neural Networks, Q. Xu, K. Krishnamurthy, Bruce M. Mcmillin, Wen Feng Lu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Recurrent neural networks have the potential to perform significantly better than the commonly used feedforward neural networks due to their dynamical nature. However, they have received less attention because training algorithms/architectures have not been well developed. In this study, a recursive least squares algorithm to train recurrent neural networks with an arbitrary number of hidden layers is developed. The training algorithm is developed as an extension of the standard recursive estimation problem. Simulated results obtained for identification of the dynamics of a nonlinear dynamical system show promising results.
Production And Decay Of D1 (2420)0 And D2* (2460)0, Avery, P.; Et Al., M. Thulasidas
Production And Decay Of D1 (2420)0 And D2* (2460)0, Avery, P.; Et Al., M. Thulasidas
Research Collection School Of Computing and Information Systems
No abstract provided.
Constraint Objects, Divesh Srivastava, Raghu Ramakrishnan, Peter Revesz
Constraint Objects, Divesh Srivastava, Raghu Ramakrishnan, Peter Revesz
CSE Conference and Workshop Papers
We describe the Constraint Object Data Model (CODM), which enhances an object-based data model with existential constraints to naturally represent partially specified information. We present the Constraint Object Query Language (COQL), a declarative, rule-based query language that can be used to infer relationships about and monotonically refine information represented in the CODM. COQL has a model-theoretic and an equivalent fixed-point semantics, based on the notions of constraint entailment and "proofs in all possible worlds." We also provide a novel polynomial-time algorithm for quantifier elimination for set-order constraints, a restricted class of set constraints that uses membership of subset-equal.
A User-Level Process Package For Concurrent Computing, Ravi Konuru, Steve Otto, Jonathan Walpole, Robert Prouty, Jeremy Casas
A User-Level Process Package For Concurrent Computing, Ravi Konuru, Steve Otto, Jonathan Walpole, Robert Prouty, Jeremy Casas
Computer Science Faculty Publications and Presentations
A lightweight user-level process(ULP) package for parallel computing is described. Each ULP has its own register context, stack, data and heap space and communication with other ULPs is performed using locally synchronous, location transparent, message passing primitives. The aim of the package is to provide support for lightweight over-decomposition, optimized local communication and transparent dynamic migration. The package supports a subset of the Parallel Virtual Machine(PVM) interface[Sun90).
Learning And Teaching Of Boolean And Geometric Classes, H. David Mathias
Learning And Teaching Of Boolean And Geometric Classes, H. David Mathias
All Computer Science and Engineering Research
We consider the concept classes of DNF formulas and unions of discretized, axis-parallel d-dimensional boxes in discretized d-dimensional space with respect to several different learning models. In the model of learning with queries we present an algorithm to learn unions of boxes. We introduce a model of teaching that prevents illicit communication between the teacher and the leaner but that captures the intuitive aspect of teaching: a learner should perform at least as well with a cooperative teacher as with an adversarial teacher. We propose the study of teaching of DNF formulas and unions of boxes in this model. We …
Scheduling Of Unstructured Communication On The Intel Ipsc/860, Jhy-Chun Wang, Sanjay Ranka
Scheduling Of Unstructured Communication On The Intel Ipsc/860, Jhy-Chun Wang, Sanjay Ranka
College of Engineering and Computer Science - Former Departments, Centers, Institutes and Projects
In this paper we present several algorithms for decomposing all-to-many personalized communication into a set of disjoint partial permutations. These partial permutations avoid node contention as well as link contention. We discuss the theoretical complexity of these algorithms and study their effectiveness both from the view of static scheduling and from runtime scheduling. Experimental results for our algorithms are presented on the iPSC/860.
Strategies For The Parallel Training Of Simple Recurrent Neural Networks, Peter J. Mccann, Barry L. Kalman
Strategies For The Parallel Training Of Simple Recurrent Neural Networks, Peter J. Mccann, Barry L. Kalman
All Computer Science and Engineering Research
Two concurrent implementations of the method of conjugate gradients for training Elman networks are discussed. The parallelism is obtained in the computation of the error gradient and the method is therefore applicable to any gradient descent training technique for this form of network. The experimental results were obtained on a Sun Sparc Center 2000 multiprocessor. The Sparc 2000 is a shared memory machine well suited to coarse-grained distributed computations, but the concurrency could be extended to other architectures as well.
An Application-Oriented Error Control Scheme For High Speed Networks, Fengmin Gong, Gurudatta Parulkar
An Application-Oriented Error Control Scheme For High Speed Networks, Fengmin Gong, Gurudatta Parulkar
All Computer Science and Engineering Research
Many new network applications demand interprocess communication (IPC) services that are not supported by existing transport protocol mechanisms. Large bandwidth-delay products of high-speed networks also render the existing control mechanisms such as flow and error control less efficient. In particular, new error control schemes that can provide variable degrees of error recovery according to the applications requirements are needed. This paper presents the design, evaluation, and implementation of an application-oriented error control scheme that is aimed at supporting efficient IPC in high-speed networking environments. Our results show that the proposed error control scheme allows effective control of trade-off between the …
Visual Presentation Of Software Specifications And Designs, Gruia-Catalin Roman, Delbert Hart, Charles Calkins
Visual Presentation Of Software Specifications And Designs, Gruia-Catalin Roman, Delbert Hart, Charles Calkins
All Computer Science and Engineering Research
Formal methods hold the promise for high dependability in the design of critical software. However, software engineers who employ formal methods need to communicate their design decisions to users, customers, managers, and collegues who may not be in a position to acquire a full understanding of the formal notation being used. Visualizations derived from formal specifications and designs must be able to convey the required information precisely and reliably without the use of formal notation. This paper discusses a design methodology which attempts to integrate a design methodology based upon specification and program refinement with a state-of-the-art approach to rapid …
Connection Management In Reconfigurable Distributed Systems, Bala Swaminathan
Connection Management In Reconfigurable Distributed Systems, Bala Swaminathan
All Computer Science and Engineering Research
The Programmer's Playground takes a new approach to simplifying and supporting the construction of distributed applications. The approach, called I/O abstraction, separates the description of a system's communication structure from the descriptions of its computational components so that software modules written in existing programming languages cna be integrated flexibly and dynamically by both programmers and end-users. This separation is achieved by estabishing logical connectinos among the data interfaces of independent software modules. The logical connections provide a uniform high-level view of communication for both discrete and continuous data. The I/O abstraction approach inherits ideas from the I/O automaton model, a …
Electronic Document Distribution: Design Of The Anonymous Ftp Langley Technical Report Server, Michael L. Nelson, Gretchen L. Gottlich
Electronic Document Distribution: Design Of The Anonymous Ftp Langley Technical Report Server, Michael L. Nelson, Gretchen L. Gottlich
Computer Science Faculty Publications
An experimental electronic dissemination project, the Langley Technical Report Server (LTRS), has been undertaken to determine the feasibility of delivering Langley technical reports directly to the desktops of researchers worldwide. During the first six months, over 4700 accesses occurred and over 2400 technical reports were distributed. This usage indicates the high level of interest that researchers have in performing literature searches and retrieving technical reports at their desktops. The initial system was developed with existing resources and technology. The reports are stored as files on an inexpensive UNIX workstation and are accessible over the Internet. This project will serve as …
World Wide Web Implementation Of The Langley Technical Report Server, Michael L. Nelson, Gretchen L. Gottlich, David J. Bianco
World Wide Web Implementation Of The Langley Technical Report Server, Michael L. Nelson, Gretchen L. Gottlich, David J. Bianco
Computer Science Faculty Publications
On January 14, 1993, NASA Langley Research Center (LaRC) made approximately 130 formal, 'unclassified, unlimited' technical reports available via the anonymous FTP Langley Technical Report Server (LTRS). LaRC was the first organization to provide a significant number of aerospace technical reports for open electronic dissemination. LTRS has been successful in its first 18 months of operation, with over 11,000 reports distributed and has helped lay the foundation for electronic document distribution for NASA. The availability of World Wide Web (WWW) technology has revolutionized the Internet-based information community. This paper describes the transition of LTRS from a centralized FTP site to …
Visual Specification Of Interprocess And Intraprocess Communication, T. Paul Mccartney, Kenneth J. Goldman
Visual Specification Of Interprocess And Intraprocess Communication, T. Paul Mccartney, Kenneth J. Goldman
All Computer Science and Engineering Research
We present a visual specification language for constructing distributed applications and their direct manipulation graphical user interfaces. Each distributed application consists of a collection of independent modules and a configuration of logical connections that define communication among the data interfaces of the modules. Our specification language uses a single visual mechanism that allows end-users to define interprocess communication among distributed modules and to define intraprocess communication among objects within a module. This seamless specification provides a general encapsulation/abstraction mechanism and is designed to support dynamic change to the communication structure. User interfaces are completely decoupled from the module(s) they control.
Congestion Control In Atm Networks, Apostolos Dailianas, Andreas Bovopoulos
Congestion Control In Atm Networks, Apostolos Dailianas, Andreas Bovopoulos
All Computer Science and Engineering Research
No abstract provided.
Rationales And Argument Moves, R. P. Loui, Jeff Norman
Rationales And Argument Moves, R. P. Loui, Jeff Norman
All Computer Science and Engineering Research
No abstract provided.
Exact Learning Of Discretized Geometric Concepts, Nader H. Bshouty, Paul W. Goldberg, Sally A. Goldman, H. David Mathias
Exact Learning Of Discretized Geometric Concepts, Nader H. Bshouty, Paul W. Goldberg, Sally A. Goldman, H. David Mathias
All Computer Science and Engineering Research
We first present an algorithm that uses membership and equivalence queries to exactly identify a discretized geometric concept defined by the unioin of m axis-parallel boxes in d-dimensional discretized Euclidean space where each coordinate can have n discrete values. This algorithm receives at most md counterexamples and uses time and membership queries polynomial in m and log(n) for any constant d. Furthermore, all equivalence queries can be formulated as the union of O(mdlog(m)) axis-parallel boxes. Next, we show how to extend our algorithm to efficiently learn, from only equivalence queries, any discretized geometric concept generated from any number of halfspaces …
Learning From A Consistently Ignorant Teacher, Michael Frazier, Sally Goldman, Nina Mishra, Leonard Pitt
Learning From A Consistently Ignorant Teacher, Michael Frazier, Sally Goldman, Nina Mishra, Leonard Pitt
All Computer Science and Engineering Research
One view of computational learning theory is that of a learner acquiring the knowledge of a teacher. We introduce a formal model of learning capturing the idea that teachers may have gaps in their knowledge. The goal of the learner is still to acquire the knowledge of the teacher, but now the learner must also identify the gaps. This is the notion of learning from a consistently ignorant teacher. We consider the impact of knowledge gaps on learning, for example, monoton DNF and d-dimensional boxes, and show that leraning is still possible. Negatively, we show that knowledge gaps make learning …
Production Quality Video Over Broadband Networks: A Description Of The System And Two Interactive Applications, William D. Richard, Jerome R. Cox Jr., A. Maynard Engebretson, Jason Fritts And Brian L. Gottlieb And Craig Horn
Production Quality Video Over Broadband Networks: A Description Of The System And Two Interactive Applications, William D. Richard, Jerome R. Cox Jr., A. Maynard Engebretson, Jason Fritts And Brian L. Gottlieb And Craig Horn
All Computer Science and Engineering Research
The Washington University MultiMedia eXplorer (MMX) is a complete, host-independent multimedia system capable of transmitting and receiving JPEG-compressed video, CD-quality audio, and high-resolution radiographic images over the Washington University broadband ATM network. If the host is equipped with an ATM interface card, normal network traffic can be supported via an ATM extension port on the MMX. The major components of the MMX are an ATMizer and three multimedia channels. The ATMizer implements the host interface, the interface to the ATM network, and hte interface to the three multimdeia channels. This paper describes the architecture of the MMX, the software used …
Performance Comparison Of Asynchronous Adders, Mark A. Franklin, Tienyo Pan
Performance Comparison Of Asynchronous Adders, Mark A. Franklin, Tienyo Pan
All Computer Science and Engineering Research
In asynchronous systems, average function delays principally govern overall throughput. This paper compares the performance of six adder designs with respect to their average delays. Our results show that asynchronous addres (32 or 64-bits) with a hybrid structure (e.g., carry-select addres) run 20-40% faster than simple ripple-carry addres. Hybrid adders also outperform high-cost, strictly synchronous conditional-sum adders.
Self-Stabilization By Counter Flushing, George Varghese
Self-Stabilization By Counter Flushing, George Varghese
All Computer Science and Engineering Research
A useful way to design simple and robust protocols is to make them self-stabilitizing. We describe a simple technique for self-stabilization called counter flushign which is applicable to a number of distributed algorithms. A randomized version of counter flushing is shown to have extremely small expected stabilization time. We show how our technique helps to crisply understand and improve some previous distributed algorithms. Then we apply it to a variety of total algorithms for deadlock detection, propagation of information with feedback, resets and snapshots. Our stabilizing snapshot protocol has much better complexity than the previous stabilizing non-blocking snapshot protocol. Hence …
Practical Methods For Approximating Shortest Paths On A Convex Polytope In R3, John Hershberger, Subhash Suri
Practical Methods For Approximating Shortest Paths On A Convex Polytope In R3, John Hershberger, Subhash Suri
All Computer Science and Engineering Research
We propose a n extremely simple approximation scheme for computing shortest paths on the surface of a convex polytope in three dimensions. Given a convex polytope P with n vertices and two points p,q on its surface, let dp (p,q) denote the shortest path distance between p and q on the surface of P. Our algorithm produces a path of length at most 2 × dp(p,q) in time O(n). Extending this results, we can also compute ana pproximation of the shortest path tree rooted at an arbitrary point χ Є P in time O(n log n). In the approximate tree, …
An Evaluation Of The Pavane Visualization System, Kenneth C. Cox, Gruia-Catalin Roman
An Evaluation Of The Pavane Visualization System, Kenneth C. Cox, Gruia-Catalin Roman
All Computer Science and Engineering Research
The Pavane program visualization system is an implementation of the declarative paradigm of visualization. After a brief report on the status of the Pavane implementation, we present the results of an evaluation of the usability of Pavane. This evaluation is based on the use of Pavane by its developers to construct program visualizations, on its use in a classroom setting as a tool for examining executing programs, and on its application to some simple scientific visualizations.
Design Of A Large Scale Multimedia Server, Milind M. Buddhikot, Guru Parulkar, Jerome R. Cox Jr.
Design Of A Large Scale Multimedia Server, Milind M. Buddhikot, Guru Parulkar, Jerome R. Cox Jr.
All Computer Science and Engineering Research
Large scale multimedia storage servers will be an integral part of the emerging distributed multimedia computing infrastructure. However, given the modest rate of improvements in storage transfer rates, designing servers that meet the demands of multimedia applications is a challenging task that needs significant architectural innovation. Our research project, called Massively-parallel And Real-time Storage (MARS) architecture, is aimed at the design and prototype implementation of a large scale multimedia storage server. It uses some of the well-known techniques in parallel I/O, such as data striping and Redundant Arrays of Inexpensive Disks (RAID) and an innovative ATM based interconnect inside the …
Universal Continuous Media I/O: Design And Implementation, Charles D. Cranor, Gurudatta M. Parulkar
Universal Continuous Media I/O: Design And Implementation, Charles D. Cranor, Gurudatta M. Parulkar
All Computer Science and Engineering Research
The problem this paper addresses is how to modify an existing operating system's I/O subsystem to support new high-speed networks and high-bandwidth multimedia applications that will play an important role in future computing environments. The proposed I/O subsystem is called universal continuous media I/O (UCM I/O). This paper will cover the preliminary design of UCM I/O, some of the trade-offs and issues that need to be addressed in order to implement UCM I/O, and a summary of work in progress.
Learning One-Dimensional Geometric Patterns Under One-Sided Random Misclassification Noise, Paul W. Goldberg, Sally A. Goldman
Learning One-Dimensional Geometric Patterns Under One-Sided Random Misclassification Noise, Paul W. Goldberg, Sally A. Goldman
All Computer Science and Engineering Research
Developing the ability to recognize a landmark from a visual image of a robot's current location is a fundamental problem in robotics. We consider the problem of PAC-learning the concept class of geometric patterns where the target geometric pattern is a configuration of k points on the real line. Each instance is a configuration of n points on the real line, where it is labeled according to whether or not it visually resembles the target pattern. To capture the notion of visual resemblance we use the Hausdorff metric. Informally, two geometric patterns P and Q resemble each othe runder the …