43104862
Program Derivation in Type Theory: A Partitioning Problem
Abstract Martin-Lof's type theory is a theory in which one can write both specifications and programs. By interpreting propositions as types, predicate logic is available when formulating a specification. The rules of type theory are formulated as tactics which makes a “top down” construction of programs possible. These ideas are illustrated by a formal derivation of a program for a partitioning problem.
30871480
Optimized Encodings of Fragments of Type Theory in First-Order Logic
16664439
An alternative approach for the evaluation of the neocognitron
The neocognitron network is analysed from the point of view of the contribution of the di erent layers to the nal classi cation. A variation to the neocognitron which gives improved performance is suggested. This variant combines the low level feature extraction capabilities of the initial layers with alternative classi ers such as LVQ and Class Based Means Clustering. This is shown to give performance which is superior to the either of those classi ers acting on their own, and to the neocognitron in its standard form on two di erent instances of the letter recognition problem.
195352472
Statistical simulation of symmetric multiprocessor systems
Statistical simulation is driven by a stream of randomly generated instructions, based on statistics collected during a single detailed simulation. This method can give accurate performance estimates within minutes, allowing a large design space to be simulated quickly. Prior work has applied this technique to superscalar processors. We evaluate the extension of statistical simulation to symmetric multiprocessing systems. Key program parameters are identified and program statistics are collected during detailed simulations for both multiprogrammed workloads (SpecInt) and parallel scientific workload (Splash-2). The accuracy of statistical simulation is evaluated at different levels of model detail, and it is shown that for multiprogrammed workloads a 10% average error can be achieved, and for parallel benchmark programs 15% average error can be achieved.
14227060
Visualization of design knowledge component relationships to facilitate reuse
Within the software development process, reuse at the requirements level has become an increasingly more compelling notion. Following a human-centric approach, this work focuses on both requirements and design solution reuse using a design knowledge repository. In recent years, many improvements have been made to increase reuse through design knowledge repositories, but retrieval of knowledge in the context of design activities continues to be a formidable challenge. We propose a new system, called CERVi, to browse a repository through visualization by exploiting relationships between units of knowledge (in our case, claims). These relationships are key to finding the most appropriate reusable knowledge based on design conditions. Testing shows that CERVi enhances the design knowledge selection process and helps users proceed through structured design decision making. Our approach would be most useful to those interested in unlocking the potential of design knowledge reuse.
932967
Modulation and Information Hiding in Images
We use concepts from communication theory to characterize information hiding schemes: the amount of information that can be hidden, its perceptibility, and its robustness to removal can be modeled using the quantities channel capacity, signal-to-noise ratio, and jamming margin. We then introduce new information hiding schemes whose parameters can easily be adjusted to trade off capacity, imperceptibility, and robustness as required in the application. The theory indicates the most aggressive feasible parameter settings. We also introduce a technique called predistortion for increasing resistance to JPEG compression. Analogous tactics are presumably possible whenever a model of anticipated distortion is available.
33417779
Implementing Large-Scale COTS Reengineering within the United States Department of Defense
This paper reports on empirical research into the organizational and process changes necessary to implement large-scale reengineering using COTS. The research goal is to identify how these changes can be effected within the context of the existing United States Department of Defense acquisition management, requirements management, and planning, programming, and budgeting systems. While this effort is still in its early stages, initial results indicate that there are significant challenges in developing and defending budget inputs to support an evolutionary COTS-oriented acquisition model. At the same time, recent changes in acquisition constraints and other mitigating circumstances are being exploited to improve the likelihood of success.