(NASA-CR-182100; ICASE-90-59; NAS 1.26:182100) Avail: NTIS HC/MF A03 CSCL 12A Runtime preprocessing plays a major role in many efficient algorithms in computer science, as well as playing an important role in exploiting multiprocessor architectures. Examples are given that elucidate the importance of runtime preprocessing and show how these optimizations can be integrated into compilers. To support the arguments, transformations implemented in prototype multiprocessor compilers are described and benchmarks from the iPSC2/860, the CM-2, and the Encore Multimax/320 are presented. 60 COMPUTER OPERATIONS AND HARDWARE Author Includes hardware for computer graphics, firmware, and data processing. For components see 33 Electronics and Electrical Engineering. N91-10601 National Aerospace Lab., Tokyo (Japan). A parallel computer is assumed as one of the future-oriented computer models. To prove its usefulness for clarifying the physical and engineering phenomena in aerospace, an architecture simulator is used which simulates movements of a parallel computer to verify the state of competition in the demand for reading/writing and the operation condition of the arithmetic operating unit and to evaluate the capacity of the computer. The architecture to be used in the project is presented. N91-10602# Department of Energy, Washington, DC. NASDA Gaetano J. Arnone, inventor (to DOE) (Los Alamos National Lab., NM.) 27 Feb. 1989 20 p (Contract W-7405-eng-36) (DE90-014681; US-Patent-Appl-SN-315871; Patents-US-A7315871) Avail: NTIS HC/MF A03 A programmable digital coincidence counter having multiple channels and featuring minimal dead time is disclosed. Neutron detectors supply electrical pulses to a synchronizing circuit which in turn inputs derandomized pulses to an adding circuit. A random access memory circuit connected as a programmable length shift register receives and shifts the sum of the pulses, and outputs to a serializer. A counter is input by the adding circuit and downcounted by the serializer, one pulse at a time. The decoded contents of the counter after each decrement is output to scalers. DOE N91-10603# Argonne National Lab., IL. ULTRA-THIN VERTICAL MAGNETO-OPTICAL MEDIA AND Samuel D. Bader, inventor (to DOE) and Chian Liu, inventor (to (Contract W-31-109-eng-38) (DE90-014589; US-Patent-Appl-SN-357246; Patents-US-A7357246) Avail: NTIS HC/MF A03 A high density information storage medium utilizing the properties of an ultrathin film was invented. The present invention includes an information storage medium comprised of an ultrathin film capable of possessing vertical magnetic orientation. The present invention also includes methods for the storage, retrieval of and erasure of data on the ultrathin film medium utilizes the temperature dependent magnetic coercivity of the ultrathin film medium. The retrieval of information from the ultrathin film medium is based on the Kerr effect property of the ultrathin film and employs detection of the rotation of a beam of polarized light. The invention also includes the beneficial utilization of the reflection of the laser from the underlying metallic substrate back through the magnetic film to enhance the rotation and reflectivity characteristics of the signal. DOE N91-10357# Meteorological Satellite Center, Tokyo (Japan). Shigenori Naito In its Meteorological Satellite Center Technical N91-10358# Meteorological Satellite Center, Tokyo (Japan). Taichi Takahashi In its Meteorological Satellite Center Technical 61 COMPUTER PROGRAMMING AND SOFTWARE Includes computer programs, routines, alogorithms, and specific applications, e.g., CAD/CAM. N91-10604 National Aerospace Lab., Tokyo (Japan). Keiji Komatsu Nov. 1987 31 p In JAPANESE The influence of the digital signal processing technology on the theoretical and experimetal aspects of the study on dynamic characteristics is becoming stronger day by day.The National Aerospace Laboratory (NAL) in these circumstances has written down and completed a basic library which makes it possible to easily conduct a time series analysis of structures and a numerical simulation with a fixed system using the programming language APL. APL was adopted since it has for its proceeding basis an array of interpreting methods capable of interactively executing a simulation and using a subroutine structure with the help of a functional language, which is characterized by the possibility of a clarifying algorithm with the aid of a short program list adapted to a time series handling. The beta method of Newmark is explained for the preparation of time series data on a structure, the program for plate bending, and three-dimensional beam by finite element method which forms its basis for inputting, the occurrence of M-series as external forces and the program for generating a In the National Aerospace Laboratory's NS system, some graphics processers are introduced. In order to assist in the use of those processors, graphics output libraries are provided in each processor. The user must learn those graphic output libraries for the various function of the processors and develop a drawing program for each piece of equipment used. In order to decrease the user's burden and to assist in the development efficiency of numerical simulation programs, the original library, the GCP library, was developed and improved. The functions of the software package and the program structure are explained in detail. Many aspects of software development with Ada have evolved as our Ada development environment has matured and personnel have become more experienced in the use of Ada. The Software Engineering Laboratory (SEL) has seen differences in the areas of cost, reliability, reuse, size, and use of Ada features. A first Ada project can be expected to cost about 30 percent more than an equivalent FORTRAN project. However, the SEL has observed significant improvements over time as a development environment progresses to second and third uses of Ada. The reliability of Ada projects is initially similar to what is expected in a mature FORTRAN environment. However, with time, one can expect to gain improvements as experience with the language increases. Reuse is one of the most promising aspects of Ada. The proportion of reusable Ada software on our Ada projects exceeds the proportion of reusable FORTRAN software on our FORTRAN projects. This result was noted fairly early in our Ada projects, and experience shows an increasing trend over time. Author N91-10608*# Maryland Univ., College Park. Inst. for Advanced TOWARDS A COMPREHENSIVE FRAMEWORK FOR REUSE: A (Contracts NSG-5123; N00014-87-K-0307; DE-AC05-84OR-21400) (UMIACS-TR-88-92; CS-TR-2158) Avail: NTIS HC/MF A16 CSCL 09B Reuse of products, processes and knowledge will be the key to enable the software industry to achieve the dramatic improvement in productivity and quality required to satisfy the anticipated growing demand. Although experience shows that certain kinds of reuse can be successful, general success has been elusive. A software life-cycle technology which allows broad and extensive reuse could provide the means to achieving the desired order-of-magnitude improvements. The scope of a comprehensive framework for understanding, planning, evaluating and motivating reuse practices and the necessary research activities is outlined. As a first step towards such a framework, a reuse-enabling software evolution environment model is introduced which provides a basis for the effective recording of experience, the generalization and tailoring of experience, the formalization of experience, and the (re-)use of experience. Author N91-10609*# National Aeronautics and Space Administration. THE SOFTWARE MANAGEMENT ENVIRONMENT (SME) (For primary document see N91-10606 01-61) The Software Management Environment (SME) is a research effort designed to utilize the past experiences and results of the Software Engineering Laboratory (SEL) and to incorporate this knowledge into a tool for managing projects. SME provides the software development manager with the ability to observe, compare, predict, analyze, and control key software development parameters such as effort, reliability, and resource utilization. The major components of the SME, the architecture of the system, and examples of the functionality of the tool are discussed. A COMMUNICATION CHANNEL MODEL OF THE SOFTWARE Robert C. Tausworthe In NASA, Goddard Space Flight Center, Avail: NTIS HC/MF A16 CSCL 09B Beginning research into a noisy communication channel analogy of software development process productivity, in order to establish quantifiable behavior and theoretical bounds is discussed. The analogy leads to a fundamental mathematical relationship between human productivity and the amount of information supplied by the developers, the capacity of the human channel for processing and transmitting information, the software product yield (object size) the work effort, requirements efficiency, tool and process efficiency, and programming environment advantage. An upper bound to productivity is derived that shows that software reuse is the only means that can lead to unbounded productivity growth; practical considerations of size and cost of reusable components may reduce this to a finite bound. Author Avail: NTIS HC/MF A16 CSCL 09B The Software Cost Engineering (SCE) methodology developed over the last two decades at IBM Systems Integration Division (SID) in Houston is utilized to cost the NASA Space Station Data Management System (DMS). An ongoing project to capture this methodology, which is built on a foundation of experiences and lessons learned, has resulted in the development of an internal-use-only, PC-based prototype that integrates algorithmic tools with knowledge-based decision support assistants. This prototype Software Cost Engineering Automation Tool (SCEAT) is being employed to assist in the DMS costing exercises. At the same time, DMS costing serves as a forcing function and provides a platform for the continuing, iterative development, calibration, and validation and verification of SCEAT. The data that forms the cost engineering database is derived from more than 15 years of development of NASA Space Shuttle software, ranging from low criticality, low complexity support tools to highly complex and highly critical onboard software. Author (For Jairus M. Hihn, Hamid Habib-agahi, and Shan Malhotra In NASA, A case study of the impact of Ada on a Command and Control project completed at the Jet Propulsion Laboratory (JPL) is given. The data for this study was collected as part of a general survey of software costs and productivity at JPL and other NASA sites. The task analyzed is a successful example of the use of rapid prototyping as applied to command and control for the U.S. Air Force and provides the U.S. Air Force Military Airlift Command with the ability to track aircraft, air crews and payloads worldwide. The task consists of a replicated database at several globally distributed sites. The local databases at each site can be updated within seconds after changes are entered at any one site. The system must be able to handle up to 400,000 activities per day. There are currently seven sites, each with a local area network of computers and a variety of user displays; the local area networks are tied together into a single wide area network. Using data obtained for eight modules, totaling approximately 500,000 source lines of code, researchers analyze the differences in productivities between subtasks. Factors considered are percentage of Ada used in coding, years of programmer experience, and the use of Ada tools and modern programming practices. The principle findings are the following. Productivity is very sensitive to programmer Avail: NTIS HC/MF A16 CSCL 09B Recent experiences with using Ada in a real time environment are described. The application was the control system for an experimental robotic arm. The objectives of the effort were to experiment with developing embedded applications in Ada, evaluating the suitability of the language for the application, and determining the performance of the system. Additional objectives were to develop a control system based on the NASA/NBS Standard Reference Model for Telerobot Control System Architecture (NASREM) in Ada, and to experiment with the control laws and how to incorporate them into the NASREM architecture. Author N91-10615*# Unisys Corp., Houston, TX. Operations Div. Daniel W. Drew and Michael Bishop In NASA, Goddard Space Avail: NTIS HC/MF A16 CSCL 09B Presented here is an approach developed at the Unisys Houston Operation Division, which supports the early identification of objects. This domain oriented analysis and development concept is based on entity relationship modeling and object data flow diagrams. These modeling techniques, based on the GOOD methodology developed at the Goddard Space Flight Center, support the translation of requirements into objects which represent the real-world problem domain. The goal is to establish a solid foundation of understanding before design begins, thereby giving greater assurance that the system will do what is desired by the customer. The transition from requirements to object oriented design is also promoted by having requirements described in terms of objects. Presented is a five step process by which objects are identified from the requirements to create a problem definition model. This process involves establishing a base line requirements list from which an object data flow diagram can be created. Entity-relationship modeling is used to facilitate the identification of objects from the requirements. An example is given of how semantic modeling may be used to improve the entity-relationship model and a brief discussion on how this approach might be used in a large scale development effort. Author A MODERNIZED PDL APPROACH FOR Ada SOFTWARE Paul Usavage, Jr. In NASA, Goddard Space Flight Center, Avail: NTIS HC/MF A16 CSCL 09B The desire to integrate newly available, graphically-oriented Computed Aided Software Engineering (CASE) tools with existing software design approaches is changing the way Program Design Language (PDL) or Process Description Language is used for large system development. In the approach documented here, Software Engineers use graphics tools to model the problem and to describe high level software design in diagrams. An Ada-based PDL is N91-10617*# Software Development Concepts, MD. REPRESENTING OBJECT ORIENTED SPECIFICATIONS AND DESIGNS WITH EXTENDED DATA FLOW NOTATIONS Jon Franklin Buser and Paul T. Ward In NASA, Goddard Space Flight Center, Proceedings of the Thirteenth Annual Software Engineering Workshop Nov. 1988 20 p (For primary document see N91-10606 01-61) Avail: NTIS HC/MF A16 CSCL 09B The issue of using extended data flow notations to document object oriented designs and specifications is discussed. Extended data flow notations, for the purposes here, refer to notations that are based on the rules of Yourdon/DeMarco data flow analysis. The extensions include additional notation for representing real-time systems as well as some proposed extensions specific to object oriented development. Some advantages of data flow notations are stated. How data flow diagrams are used to represent software objects are investigated. Some problem areas with regard to using data flow notations for object oriented development are noted. Some initial solutions to these problems are proposed. Author N91-10618*# Alabama Univ., Huntsville. (Grant NAG8-720) (NASA-CR-185880; NAS 1.26:185880; Rept-90-18-Vol-1) Avail: NTIS HC/MF A03 CSCL 09B This volume (1 of 4) gives a summary of the original AMPS software system configuration, points out some of the problem areas in the original software design that this project is to address, and in the appendix collects all the bimonthly status reports. The purpose of AMPS is to provide a self reliant system to control the generation and distribution of power in the space station. The software in the AMPS breadboard can be divided into three levels: the operating environment software, the protocol software, and the station specific software. This project deals only with the operating environment software and the protocol software. The present station specific software will not change except as necessary to conform to new data formats. N91-10619*# Alabama Univ., Huntsville. James W. McKee 1990 119 p (Grant NAG8-720) E.R. (NASA-CR-185881; NAS 1.26:185881; Rept-90-18-Vol-2) Avail: NTIS HC/MF A06 CSCL 09B This volume (2 of 4) contains the specification, structured flow charts, and code listing for the protocol. The purpose of an autonomous power system on a spacecraft is to relieve humans from having to continuously monitor and control the generation, storage, and distribution of power in the craft. This implies that algorithms will have been developed to monitor and control the power system. The power system will contain computers on which the algorithms run. There should be one control computer system that makes the high level decisions and sends commands to and receive data from the other distributed computers. This will require a communications network and an efficient protocol by which the computers will communicate. One of the major requirements on the protocol is that it be real time because of the need to control the power elements. E.R. N91-10620*# Alabama Univ., Huntsville. NETWORK, SYSTEM, AND STATUS SOFTWARE ENHANCEMENTS FOR THE AUTONOMOUSLY MANAGED ELECTRICAL POWER SYSTEM BREADBOARD. VOLUME 3: COMMANDS SPECIFICATION Research Report, Jun. 1988 May 1990 James W. McKee 1990 15 P (Grant NAG8-720) (NASA-CR-185882; NAS 1.26:185882; Rept-90-18-Vol-3) Avail: NTIS HC/MF A03 CSCL 09B This volume (3 of 4) contains the specification for the command language for the AMPS system. The volume contains a requirements specification for the operating system and commands and a design specification for the operating system and command. The operating system and commands sits on top of the protocol. The commands are an extension of the present set of AMPS commands in that the commands are more compact, allow multiple sub-commands to be bundled into one command, and have provisions for identifying the sender and the intended receiver. The commands make no change to the actual software that E.R. implement the commands. This volume (4 of 4) contains the description, structured flow charts, prints of the graphical displays, and source code to generate the displays for the AMPS graphical status system. The function of these displays is to present to the manager of the AMPS system a graphical status display with the hot boxes that allow the manager to get more detailed status on selected portions of the AMPS system. The development of the graphical displays is divided into two processes; the creation of the screen images and storage of them in files on the computer, and the running of the status program which uses the screen images. E.R. N91-10622# National Oceanic and Atmospheric Administration, (PB90-220310; NOAA-TM-ERL-WPL-176) Avail: NTIS HC/MF Over the next couple of years, Wave Propagation Laboratory (WPL) is making the transition from several different operating systems on its various platforms to UNIX, which is fast becoming the computer industry standard. The report records many of the tasks involved in converting from DEC's VMS (Virtual Memory System) operating system to ULTRIX on one of WPL's micro VAX's. It emphasizes the user's perspective and, thus, avoids most of the system-level work. It should, as a result, serve as a handy reference manual for those making the transition from VMS to ULTRIX. GRA N91-10623*# Michigan Univ., Ann Arbor. Radiation Lab. (NASA-CR-186929; NAS 1.26:186929; Rept-025921-15-T) Avail: NTIS HC/MF A03 CSCL 09B AUTOMESH-2D is a computer program specifically designed as a preprocessor for the scattering analysis of two dimensional bodies by the finite element method. This program was developed due to a need for reproducing the effort required to define and check the geometry data, element topology, and material properties. There are six modules in the program: (1) Parameter Specification; (2) Data Input; (3) Node Generation; (4) Element Generation; (5) Mesh Smoothing; and (5) Data File Generation. Author N91-10624# NSI Technology Services Corp., Corvallis, OR. D. L. Kugler and E. H. Lee 1990 8 P Interval estimates for nonlinear parameters using the linear approximation are sensitive to parameter curvature effects. The adequacy of the linear approximation interval is determined using the nonlinearity measures of Bates and Watts, and Clarke, and the profile t plots of Bates and Watts. These curvature measures and profile t plot calculations are implemented using the SAS/IML and SAS/NLIN procedures. N91-10625# Author National Aeronautical Lab., Bangalore (India). Structural Sciences Div. SCRIPT: GENERAL PURPOSE GRAPHICS PROGRAM; USER'S MANUAL (DE90-015147; UCRL-JC-104204; CONF-9009225-1) Avail: NTIS HC/MF A03 The user is presented with a method of converting a 3-D wire frame model into a technical illustration, detail, or assembly drawing. By using the 2D Program, entities can be mapped from 3-D model space into two-dimensional model space, as if they are being traced. Selected entities to be mapped can include circles, arcs, lines, and points. This program prompts the user to digitize the view to be mapped, specify the layers in which the new 2-D entities will reside, and select the entities, either by digitizing or windowing. The new 2-D entities are displayed in a small view which the program creates in the lower left corner of the drawing. DOE (Ma-55; ISBN-951-666-304-4; ISSN-0355-2713; ETN-90-97631) Avail: NTIS HC/MF A07 Two CASE (Computer Assisted Software Engineering) tools for CIM (Computer Integrated Manufacturing) are defined: CIMVIEW for high level, functional, top-down integration, company specific analysis and modeling, and CIMGLUE for low level, bottom-up integration, interfacing of existing applications. A method, STIF, is defined for interface program design to reduce the need to change the interface during the normal evolution of the applications. In CIMVIEW the user builds interactively a SA/SD data flow model of the functions of the company being examined. CIMGLUE, is a general tool to build conversion programs between almost any software packages a and b. The conversion program is built interactively utilizing example of package a's output and package b's input. Both CIMGLUE and CIMVIEW tools are described generally for different types of implementations. A CIMVIEW prototype was implemented based on common lisp and common windows. In the STIF (Semantically Transparent Interfacing) method the variable definitions of transferred items are isolated as much outside the interface as possible instead of using cross references inside the interface. This is done by embedding some elements of the definition language of package 1 into the definition language of package 2. Two example cases in which the method was applied are described. The interfaces are in use in practical industrial applications. ESA N91-10628*# Institute for Computer Applications in Science and Engineering, Hampton, VA. CONSERVATIVE PARALLEL SIMULATION OF PRIORITY David M. Nicol (College of William and Mary, Williamsburg, VA.) (NASA-CR-187438; ICASE-90-64; NAS 1.26:187438) Avail: NTIS HC/MF A03 CSCL 09B A conservative synchronization protocol is described for the parallel simulation of queueing networks having C job priority classes, where a job's class is fixed. This problem has long vexed designers of conservative synchronization protocols because of its seemingly poor ability to compute lookahead: the time of the next departure. For, a job in service having low priority can be preempted at any time by an arrival having higher priority and an arbitrarily small service time. The solution is to skew the event generation activity so that the events for higher priority jobs are generated farther ahead in simulated time than lower priority jobs. Thus, when a lower priority job enters service for the first time, all the higher priority jobs that may preempt it are already known and the job's departure time can be exactly predicted. Finally, the protocol was analyzed and it was demonstrated that good performance can be expected on the simulation of large queueing networks. Author N91-10629*# Institute for Computer Applications in Science and Engineering, Hampton, VA. A CONSERVATIVE APPROACH TO PARALLELIZING THE SHARKS WORLD SIMULATION Final Report David M. Nicol and Scott E. Riffe Oct. 1990 15 p Submitted for publication (Contract NAS1-18605; NAG1-1060; NSF ASC-88-19373) (NASA-CR-187440; NAS 1.26:187440; ICASE-90-67) Avail: NTIS HC/MF A03 CSCL 09B Parallelizing a benchmark problem for parallel simulation, the Sharks World, is described. The described solution is conservative, in the sense that no state information is saved, and no 'rollbacks' occur. The used approach illustrates both the principal advantage and principal disadvantage of conservative parallel simulation. The advantage is that by exploiting lookahead an approach was found that dramatically improves the serial execution time, and also achieves excellent speedups. The disadvantage is that if the model rules are changed in such a way that the lookahead is destroyed, it is difficult to modify the solution to accommodate the changes. Author N91-10630# Sandia National Labs., Albuquerque, NM. 1990 7 p Presented at the Workshop on Design and Assurance (DE90-016222; SAND-90-2255C; CONF-9010171-2) Avail: NTIS HC/MF A02 More than 20 years ago, a philosophy was developed for the design and analysis of hardware systems to ensure that they would |