Lamprey eel harvesting has systematically and periodically occurred along the Siletz River and its tributaries for as many as hundreds, or thousands, or tens of thousands of years that human families and lamprey eel populations have coexisted in the Siletz Valley ecosystem. Historical, cultural, and biological information for the twentieth...
We believe concreteness, direct manipulation and responsiveness in a visual programming language increase its usefulness. However, these characteristics present a challenge in generalizing programs for reuse, especially when concrete examples are used as one way of achieving concreteness. In this paper, we present a technique to solve this problem by...
This PNW Extension publication provides an overview of various types of powderpost beetles, the symptoms associated with their damage, as well as tips for prevention and control.
This document defines the language Leda as currently implemented by the authors and Vinoo Cherian. Leda is an evolving research language and readers may wish to consult the bibliography for a variety of papers concerning its raison d'être. Our purpose here is to guide investigators in the use of a...
Most designers of object-based languages adopt a reference model of variables without explicit justification, despite its wide ranging consequences. This paper argues that the traditional container model of variables is more efficient than the reference model, nearly as flexible, and more appropriate to parallel and distributed systems. The topics addressed...
A weakness of many interactive visual programming languages (VPLs) is their static representations. Lack of an adequate static representation places a heavy cognitive burden on a VPL's programmers, because they must remember potentially long dynamic sequences of screen displays in order to understand a previously-written program. However, although this problem...
Dataparallel C is a SIMD extension to the standard C programming language. It is derived from the original C* language developed by Thinking Machines Corporation.. We have nearly completed a third-generation Dataparallel C compiler, which transforms Dataparallel C programs into SPMD-style C code suitable for compilation and execution on NCUBE...
Large integer factorization exemplifies a class of hard computational problems requiring the power of a supercomputer but which have algorithms decomposable into many large independent computations. The availability of internetworking provides the opportunity to solve such problems in distributed fashion on ordinary machines. Such a distributed network might contain a...
It often makes sense to write a program in the SIMD style, even if the program is to execute on a MIMD computer. Simulating physical events, in which all motion takes place simultaneously, is one area in which SIMD languages fit the applications particularly well. In this paper we present...
The Parallel Programming Support Environment (PPSE) is an experimental integrated set of tools for the design and construction of large software systems to run on parallel computers. The tools include a graphical de.sign editor, a graphical target machine description system, a task mapper/scheduler tool, parallel code generator, and graphical aids...
We are convinced that the combination of data-parallel languages and MIMD hardware can make an important contribution to high speed computing. The data-parallel paradigm is a natural way to solve a large number of problems arising in science and engineering. Data-parallel programs are easier to design, implement, and debug than...
We describe our third generation C* compiler for a hypercube multicomputer. This production quality compiler features a full implementation of the language, including general pointer-based communication and support for separate compilation. The compiler incorporates new optimizations and utilizes an improved set of communication primitives. It supports a variety of standard...
Parallel software development requires the flexibility to describe algorithms regardless of hardware specification, the ability to accommodate existing applications. and maintainability throughout the software life cycle. We propose the following model to address these issues. Our model incorporates aspects of the object-oriented and large grain data flow programming paradigms, and...
The coverage of a learning algorithm is the number of concepts that can be learned by that algorithm from samples of a given size. This paper asks whether good learning algorithms can be designed by maximizing their coverage. The paper extends a previous upper bound on the coverage of any...
This paper applies learning techniques to make engineering optimization more efficient and reliable. When the function to be optimized is highly non-linear, the search space generally forms several disjoint convex regions . Unless gradient-descent search is begun in the right region, the solution found will be suboptimal. This paper formalizes...
Visual Fortran D (VFD) is a graphical tool to assist parallel programmers in specifying data distributions. Its target is Fortran D, an extension to Fortran77 or Fortran90 which supports data parallelism. VFD provides an intuitive framework where the user employs simple, fast graphical manipulations to specify how data is to...
This paper describes HelpDez, a colored-Petri-net-based approach for the design, simulation, and construction of hypermedia help systems. The storage model, system capabilities, and user interface model of a hypermedia help system are examined. Colored Petri nets are chosen to model hypermedia help systems due to their graphical expressiveness and their...
Consider the problem of exploring a large state-space for a goal state where although many such states may exist in the state-space, finding any one state satisfying the requirements is sufficient. All the methods known until now for conducting such search in parallel using multiprocessors fail to provide consistent linear...
Heuristics for static scheduling of task graphs using list scheduling techniques have continued to improve by adding real-world factors such as processor speed, network transmission speed, interconnection topology, and link contention considerations to the basic task graph model. Yet, the resulting schedules do not fully model program loops and branches,...