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Solving Common Mathematical Problems

Mathematical Solutions Toolset is a collection of five software programs that rapidly solve some common mathematical problems.

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Interactive Display of Scenes With Annotations

ThreeDView is a computer program that enables high-performance interactive display of real-world scenes with annotations. ThreeDView was developed primarily as a component of the Science Activity Planner (SAP) software, wherein it is to be used to display annotated images of terrain acquired by exploratory robots on Mars and possibly other remote planets. The images can be generated from sets of multiple-texture image data in the Visible Scalable Terrain (ViSTa) format, which was described in “Format for Interchange and Display of 3D Terrain Data” (NPO-30600) NASA Tech Briefs, Vol. 28, No. 12 (December 2004), page 25. In ThreeDView, terrain data can be loaded rapidly, the geometric level of detail and texture resolution can be selected, false colors can be used to represent scientific data mapped onto terrain, and the user can select among navigation modes. Three-DView consists largely of modular Java software components that can easily be reused and extended to produce new high-performance, application-specific software systems for displaying images of three-dimensional real-world scenes.

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Tools for Designing and Analyzing Structures

Structural Design and Analysis Toolset is a collection of approximately 26 Microsoft Excel spreadsheet programs, each of which performs calculations within a different subdiscipline of structural design and analysis.

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Sizing Structures and Predicting Weight of a Spacecraft

EZDESIT is a computer program for choosing the sizes of structural components and predicting the weight of a spacecraft, aircraft, or other vehicle. In designing a vehicle, EZDESIT is used in conjunction with a finite-element structural- analysis program: Each structural component is sized within EZDESIT to withstand the loads expected to be encountered during operation, then the weights of all the structural finite elements are added to obtain the structural weight of the vehicle. The sizing of the structural components elements also alters the stiffness properties of the finite-element model. The finite-element analysis and structural component sizing are iterated until the weight of the vehicle converges to a prescribed iterative difference. The results of the sizing can be reviewed in two ways: 1. An interactive session of the EZDESIT program enables review of the results in a table that shows component types, component weights, and failure modes; and 2. The results are read into a finite-element preprocessing-and-postprocessing program and displayed on a graphical representation of the model.

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Stress Testing of Data-Communication Networks

NetStress is a computer program that stress-tests a data-communication network and components thereof. NetStress comprises two components running, respectively, in a transmitting system and a receiving system connected to a network under test. The novelty of the program is that is has the capability to generate/receive varied network loading traffic profiles, which prior known programs were incapable of producing (i.e., various packet sizes and various packet rates all combined to make a pseudo-random traffic pattern). The transmitting-system component generates increasingly stressful data traffic for transmission via the network. The receiving- system component analyzes the resulting traffic arriving in the receiving system, generating such statistics as the number of data packets successfully received, the number of dropped packets, and the number of packets received out of order. The packet sizes must be configured before the transmitting-system component is started, but the packet frequencies, numbers of packets in bursts, and burst times can be configured during execution. Typically, a test begins with transmission of data at low sustained rates. Then the sustained rates are increased and burst rates are modified while monitoring to determine whether the receiving-system component reports any losses. When significant losses are reported, the user seeks to determine whether a malfunction or deficiency has been found or normal network saturation has been attained. NetStress was written for execution in the VxWorks real-time operating system, but could easily be ported to other operating systems.

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Framework for Flexible Security in Group Communications

The Antigone software system defines a framework for the flexible definition and implementation of security policies in group communication systems. Antigone does not dictate the available security policies, but provides high-level mechanisms for implementing them. A central element of the Antigone architecture is a suite of such mechanisms comprising micro-protocols that provide the basic services needed by secure groups. Policies are implemented through the composition and configuration of these mechanisms. Mechanisms are composed in different ways to address new requirements and environ-mental constraints. The Antigone framework provides an easy-to-use application programming interface (API), from which secure group application programs can be built. Written entirely in the C++ programming language, the system consists of over 18,000 lines of source code and has been ported to several versions of Linux, FreeBSD, and SunOS. Information for accessing recent versions of the source code and related documentation is available at http://antigone.eecs.umich.edu.

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Integrated Modeling Environment

The Integrated Modeling Environment (IME) is a software system that establishes a centralized Web-based interface for integrating people (who may be geographically dispersed), processes, and data involved in a common engineering project. The IME includes software tools for life-cycle management, configuration management, visualization, and collaboration. It enables organized, efficient communication of engineering analyses and the statuses thereof. Key functions performed by use of the IME include creation, further development, and management of modeling analyses over their entire life cycles; publishing model and analysis information for availability and reuse throughout the user community; and managing legacy information without regard to original formats, database organizations, or computing platforms. The use of the IME creates an archive of analysis results, plus documentation that identifies the assumptions and data elements used for each analysis. This archive is configured to enable reuse of previous analysis results, and tracing of types and versions of software used for each step of each analysis. The IME utilizes a customized version of a commercial product-life-cycle-management application program that provides rich capabilities for managing configurations, workflows, data, and access through a single Web-based environment.

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