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Experiences in effective use of Tcl/Tk

Description: Tcl/Tk (Toot Command Language and Tool Kit, pronounced ``tickle tee-kay``) is a scripting language supporting Motifm style X Window interfaces. It is extendible, allowing developers to embed additional functionality as commands in the language. However, the power and flexibility of the system leads to many variations or possibilities in its usage. We describe effective methods for taking advantage of Tcl/Tk to increase productivity and enhance the flexibility and adaptability of applications: writing simple Tcl/Tk scripts, extending the Tcl/Tk widget set, wrapping Tcl commands around existing classes and functions, and building Tcl/Tk and 3GL coprocesses. Examples are presented from working applications.
Date: June 1, 1995
Creator: Lee, R.W.
Partner: UNT Libraries Government Documents Department

Users manual for bfort: Producing Fortran interfaces to C source code

Description: In many applications, the most natural computer language to write in may be different from the most natural language to provide a library in. For example, many scientific computing applications are written in Fortran, while many software libraries-particularly those dealing with complicated data structures or dynamic memory management-are written in C. Providing an interface so that Fortran programs can call routines written in C can be a tedious and error-prone process. We describe here a tool that automatically generates a Fortran-callable wrapper for routines written in C, using only a small, structured comment and the declaration of the routine in C. This tool has been used on two large software packages, PETSc and the MPICH implementation of MPI.
Date: March 1, 1995
Creator: Gropp, W.
Partner: UNT Libraries Government Documents Department

CAMAC Driver Support for Windows NT{trademark} and Lunux{trademark}

Description: CAMAC is a Modular Instrumentation and Digital Interface System defined as a standardized instrumentation system for Computer Automated Measurement and Control. CAMAC hardware and software has been defined by the NIM Committee (National Instrumentation Methods Committee) of the US Department of Energy and the ESONE Committee (European Standards on Nuclear Electronics Committee) of European Laboratories. Fermi National Accelerator Laboratory has for many years produced software packages that follow the ANSI/IEEE standard 758-1979 for a variety of computers, CAMAC controller interfaces, and operating systems. In order to enable the re-use of existing hardware and software, Fermilab now supports standard routine libraries and drivers for Windows NT 4.0 and the Linux operating systems for the Jorway 411s SCSI Bus CAMAC Driver[l] and the Jorway73A SCSI Bus CAMAC Crate Controller. A number of test stands and small experiments both on-site and off-site are using this software for their CAMAC data acquisition needs.
Date: July 27, 1999
Creator: Streets, D.A. Slimmer and J.M.
Partner: UNT Libraries Government Documents Department

Overview of PV balance-of-systems technology: Experience and guidelines for utility ties in the United States of America

Description: The U.S. National Photovoltaic Program began in 1975 by supporting the development of terrestrial PV modules and hardware associated with grid-connected PV systems. Early PV-system demonstration programs were also supported and cost shared by the U.S. Department of Energy (DOE). A wide variety of PV systems were deployed, usually with utility participation. The early demonstration projects provided, and continue to provide, valuable PV system experience to utilities, designers and suppliers. As a result of experience gained, several important milestones in codes and standards pertaining to the design, installation and operation of photovoltaic (PV) systems have been completed. These code and standard activities were conducted through collaboration of participants from all sectors of the PV industry, utilities and the US DOE National Photovoltaic Program. Codes and standards that have been proposed, written, or modified include changes and additions for the 1999 National Electric Code{reg_sign} (NEC{reg_sign}), standards for fire and personnel safety, system testing, field acceptance, component qualification, and utility interconnection. Project authorization requests with the Institute of Electrical and Electronic Engineers (IEEE) have resulted in standards for component qualification and were further adapted for standards used to list PV modules and balance-of-system components. Industry collaboration with Underwriter Laboratories, Inc., with the American Society for Testing and Materials, and through critical input and review for international standards with the International Electrotechnical Commission have resulted in new and revised domestic and international standards for PV applications. Activities related to work on codes and standards through the International Energy Agency are also being supported by the PV industry and the US DOE. The paper shows relationships between activities in standards writing.
Date: October 1, 1997
Creator: Bower, W. & Whitaker, C.
Partner: UNT Libraries Government Documents Department

Low-power, parallel photonic interconnections for Multi-Chip Module applications

Description: New applications of photonic interconnects will involve the insertion of parallel-channel links into Multi-Chip Modules (MCMs). Such applications will drive photonic link components into more compact forms that consume far less power than traditional telecommunication data links. MCM-based applications will also require simplified drive circuitry, lower cost, and higher reliability than has been demonstrated currently in photonic and optoelectronic technologies. The work described is a parallel link array, designed for vertical (Z-Axis) interconnection of the layers in a MCM-based signal processor stack, operating at a data rate of 100 Mb/s. This interconnect is based upon high-efficiency VCSELs, HBT photoreceivers, integrated micro-optics, and MCM-compatible packaging techniques.
Date: December 31, 1994
Creator: Carson, R.F.; Lovejoy, M.L. & Lear, K.L.
Partner: UNT Libraries Government Documents Department

A DSP based power electronics interface for alternate/renewable energy systems. Quarterly report 3.

Description: This report is an update on the research project involving the implementation of a DSP based power electronics interface for alternate/renewable energy systems that was funded by the Department of Energy under the Inventions and Innovations program 1998. The objective of this research is to develop a utility interface (dc to ac converter) suitable to interconnect alternate/renewable energy sources to the utility system. The DSP based power electronics interface in comparison with existing methods will excel in terms of efficiency, reliability and cost. Moreover DSP-based control provides the flexibility to upgrade/modify control algorithms to meet specific system requirements. The proposed interface will be capable of maintaining stiffness of the ac voltages at the point of common coupling regardless of variation in the input dc bus voltage. This will be achieved without the addition of any extra components to the basic interface topology but by inherently controlling the inverter switching strategy in accordance to the input voltage variation.
Date: March 31, 2000
Partner: UNT Libraries Government Documents Department

An object oriented software bus

Description: This paper describes a new approach to development of software for highly integrated software-hardware systems such as used for data acquisition and control. This approach, called the Object Oriented Software Bus (OSB), is a way to develop software according to a common specification similar to the way interface hardware has been developed since the advent of bus structures for minicomputers and microcomputers. Key concept of the OSB is extension of the common use of objects to support user interface and data analysis functions to the development of software objects that directly correspond to real- world hardware interfaces and modules.
Date: December 31, 1995
Creator: McGirt, F. & Wilkerson, J.F.
Partner: UNT Libraries Government Documents Department

Design and testing of a high power, ultra-high vacuum, dual-directional coupler for the Advanced Photon Source (APS) linear accelerator

Description: Leaks and cracks have developed in the vacuum windows of the linac WR 284 waveguide directional couplers. In the existing coupler design the vacuum window is brazed to the waveguide. Replacement of a cracked window requires the removal of the component from the waveguide system resulting in a loss of vacuum in the waveguide. A new design has been developed and a prototype tested that utilizes bolted-in vacuum windows and allows for easier replacement of the windows in the system, while still providing suitable radio frequency (rf) specifications.
Date: July 1, 1995
Creator: Brauer, S.O.; Grelick, A.E.; Grimmer, J.; Otocki, R.D.; Kang, Y.W.; Noonan, J. et al.
Partner: UNT Libraries Government Documents Department

XTOD - XES Interface Control Document

Description: This document describes the interface between the LCLS XTOD System (WBS No.1.5) and the LCLS XES (WBS No.1.6). The interface locations ranging from the beam dump to the far experimental hall are identified. Subsystems that connect at or cross the boundary are identified.
Date: September 7, 2005
Creator: Trent, J
Partner: UNT Libraries Government Documents Department

Infrastructure and interfaces for large-scale numerical software.

Description: The complexity of large-scale scientific simulations often necessitates the combined use of multiple software packages developed by different groups in areas such as adaptive mesh manipulations, scalable algebraic solvers, and optimization. Historically, these packages have been combined by using custom code. This practice inhibits experimentation with and comparison of multiple tools that provide similar functionality through different implementations. The ALICE project, a collaborative effort among researchers at Argonne National Laboratory, is exploring the use of component-based software engineering to provide better interoperability among numerical toolkits. They discuss some initial experiences in developing an infrastructure and interfaces for high-performance numerical computing.
Date: June 10, 1999
Creator: Freitag, L.; Gropp, W. D.; Hovland, P. D.; McInnes, L. C. & Smith, B. F.
Partner: UNT Libraries Government Documents Department

A standard interface for debugger access to message queue information in MPI.

Description: This paper discusses the design and implementation of an interface that allows a debugger to obtain the information necessary to display the contents of the MPI message queues. The design has been implemented in the TotalView debugger, and dynamic libraries that conform to the interface exist for MPICH, as well as the proprietary MPI implementations from Compaq, IBM, and SGI.
Date: June 25, 1999
Creator: Cownie, J. & W., Gropp.
Partner: UNT Libraries Government Documents Department

Scalable Parallel Utopia

Description: This contribution proposes a 128 bit wide interface structure clocked at approximately 80 MHz that will operate at 10 Gbps as a strawman for a 0C192C Utopia Specification. In addition, the concept of scalable width of data transfers in order to maintain manageably low clock rates is proposed.
Date: October 1, 1998
Creator: King, D. & Pierson, L.
Partner: UNT Libraries Government Documents Department

A Simulation Study of the Virtual Interface Architecture

Description: The Virtual Interface Architecture (VIA) is an emerging standard for interconnecting commodity computing nodes into a cluster. Since VIA protocol. operations are implemented outside the operating system kernel (often, entirely in hardware), VIA transfers can be performed at very low delay, high throughput, and minimal CPU overhead. This makes VIA ideal when building large clusters that perform complex simulations of physical events, However, the scaling properties of VIA are less clear. This paper describes the design and results of a simulation model developed in OPNET to investigate VIA's ability to scale to clusters of> 1000 nodes.
Date: May 18, 1999
Creator: Hu, Tan Chang; Stans, Leonard & Tarman, Thomas D.
Partner: UNT Libraries Government Documents Department

The BUG BITBUS Universal Gateway

Description: The BITBUS Universal Gateway (BUG) provides a unique, cost effective solution to many different computer interface problems. Each BUG node, utilizing ``on board`` intelligence, has the ability to provide a communication link between BITBUS protocol and other computer-signal interfaces. Among them, IEEE-488, RS232, and raw analog and binary signal 1/0. BITBUS is a multidrop, multinode link with the ability to communicate over great distances. By using this method of signal transfer, along with the communication conversion ability of the BUG, one could accomplish such things as the ability to run IEEE-488 instruments over great distances, extend a multidrop links to RS232 instruments, and provide a convenient interface point for remote analog and binary 1/0 signals, all on one homogeneous network. The BUG not only provides this through the wired ``twisted pair`` standard of BITBUS, but extends the ability to fiber optic communications for signal transfer over extreme distances and through electrically ``noisy`` environments.
Date: February 1, 1996
Creator: Nawrocki, G.
Partner: UNT Libraries Government Documents Department

Interlock and control systems for a sector at the APS

Description: This report describes some basic elements of the various Interlock and Control Systems associated with the Front Ends and Beamlines. Some systems serve only the Front Ends; other serve both the Front Ends and the Beamlines, while the Experimental Controls are for the Beamlines only. Specific system requirements and design specifications are not in the scope of this report. They will be presented in the descriptions of the Experimental Floor Personnel Safety System (XF-PSS or, more often, PSS) and Equipment Protection System (XF-EPS or EPS), which will expand on the overview presented here. The main focus here is on the PSS and EPS in the context of their interactions and interface to the Storage Ring Access Control Interlock System (ACIS), and Ring Controls. The other systems are only mentioned to make the cross section complete. This paper is the first in series of three reports that jointly provide a full description of sector interlocks. The second report describes the PSS, and the third -- the EPS.
Date: September 9, 1993
Creator: Friedman, N.
Partner: UNT Libraries Government Documents Department

On the implementation of error handling in dynamic interfaces to scientific codes

Description: With the advent of powerful workstations with windowing systems, the scientific community has become interested in user friendly interfaces as a means of promoting the distribution of scientific codes to colleagues. Distributing scientific codes to a wider audience can, however, be problematic because scientists, who are familiar with the problem being addressed but not aware of necessary operational details, are encouraged to use the codes. A more friendly environment that not only guides user inputs, but also helps catch errors is needed. This thesis presents a dynamic graphical user interface (GUI) creation system with user controlled support for error detection and handling. The system checks a series of constraints defining a valid input set whenever the state of the system changes and notifies the user when an error has occurred. A naive checking scheme was implemented that checks every constraint every time the system changes. However, this method examines many constraints whose values have not changed. Therefore, a minimum evaluation scheme that only checks those constraints that may have been violated was implemented. This system was implemented in a prototype and user testing was used to determine if it was a success. Users examined both the GUI creation system and the end-user environment. The users found both to be easy to use and efficient enough for practical use. Moreover, they concluded that the system would promote distribution.
Date: November 1, 1993
Creator: Solomon, C.J.
Partner: UNT Libraries Government Documents Department

Recommendations for developing portable parallel I/O facilities forscientific applications

Description: We outline a plan to develop portable parallel I/O facilities for scientific applications on parallel computers. We recommend that efforts be focussed on three areas: a new standard I/O library for message passing environments, efficient parallel I/O implementations for data parallel programming in Fortran 90 and High Performance Fortran (which may require new parallel I/O commands), and the promotion of high performance parallel I/O facilities in high-level scientific toolkits. In the next year we will concentrate primarily on the first area, designing and implementing a portable parallel I/O library to work with the new MPI standard Message Passing Interface.
Date: December 1, 1994
Creator: Yates, R.K.
Partner: UNT Libraries Government Documents Department

High-speed connections for storage systems; HIPPI, fibre channel, and ATM: Whats happening?

Description: A group of eight Digital Equipment Corporation Alpha workstations is interconnected with ATM to form a cluster with supercomputer power. For output, each workstation drives a single ``tile`` on an 8-tile high-resolution frame buffer. A special purpose adapter is used to convert the workstation`s ATM format to the frame buffer`s HIPPI format. This paper discusses the rationale behind the workstation farm, and then describes the visualization output path in detail. To provide the system quickly, special emphasis was placed on making the design as simple as possible. The design choices are examined, and the resultant system is described. The oral presentation will include operational experiences.
Date: April 1, 1995
Creator: Tolmie, D.E.
Partner: UNT Libraries Government Documents Department

Computers and small satellites: How FORTE is utilizing the WWW as a {open_quotes}paperless{close_quotes} information resource and the development of a unique resource management planning tool

Description: The Fast-On-orbit Recording of Transient Events (FORTE) satellite is the second satellite to be developed and flown by Los Alamos National Laboratory and is scheduled to be launched August, 1997 by a Pegasus XL rocket. FORTE follows in the footsteps of the ALEXIS satellite in utilizing a very small operations crew for mission operations. Partially based upon the ALEXIS automation and World Wide Web (WWW) usage for data dissemination, FORTE began at an early stage of ground processing to use the web as a repository of information about all aspects of the satellite. Detailed descriptions of the various satellite and experiment components, cable diagrams, integration photographs as well as extensive test data have all been compiled into a single site as a means of archiving the data at a single location. In this manner, it is readily available during times of ground testing, ground station operation training as well as anomaly resolution. Small satellites usually require extensive effort to optimize operation under minimal resources. For the FORTE satellite, a unique planning tool has been developed over the past 2 years which balances the various resources of the satellite (power, memory, downlink, on board command buffer, etc.) to provide the maximum data acquisition. This paper will concentrate on a description of both the extensive web interface and the planning tool. 6 refs.
Date: October 1, 1997
Creator: Roussel-Dupre, D.; Carter, M. & Franz, R.
Partner: UNT Libraries Government Documents Department

Protocols and standard crate configuration for a typical CDF Run 2 readout crate

Description: This paper describes a standard for the readout and the trigger interface of a VMEbus based crate to be used by the front-end and trigger electronics of the CDF Run 2 experiment. Hereafter, this crate will be referred to as the CDF Readout Crate. The goal is to standardize the implementation of functions that are common among all systems (i.e. power distribution, timing signals, DAQ functions) while allowing some flexibility with other functions (e.g. cooling, rear transition modules, J3 backplanes, etc.). This allows designers of cards that satisfy this standard to have access to a common well defined crate system with interfaces to the trigger and DAQ system, allowing them to concentrate their efforts on the functions they need. This paper lists the mechanical specifications, readout scheme, backplane and signal distribution specifications of the CDF Readout Crate. The paper will also go into some detail on the TRigger And Clock + Event Readout (TRACER) module, a common CDF crate module which provides the crate interface to the system clock and the trigger system.
Date: November 5, 1999
Creator: al., Theresa Shaw et
Partner: UNT Libraries Government Documents Department

Implementing virtual reality interfaces for the geosciences

Description: For the past few years, a multidisciplinary team of computer and earth scientists at Lawrence Berkeley National Laboratory has been exploring the use of advanced user interfaces, commonly called {open_quotes}Virtual Reality{close_quotes} (VR), coupled with visualization and scientific computing software. Working closely with industry, these efforts have resulted in an environment in which VR technology is coupled with existing visualization and computational tools. VR technology may be thought of as a user interface. It is useful to think of a spectrum, ranging the gamut from command-line interfaces to completely immersive environments. In the former, one uses the keyboard to enter three or six-dimensional parameters. In the latter, three or six-dimensional information is provided by trackers contained either in hand-held devices or attached to the user in some fashion, e.g. attached to a head-mounted display. Rich, extensible and often complex languages are a vehicle whereby the user controls parameters to manipulate object position and location in a virtual world, but the keyboard is the obstacle in that typing is cumbersome, error-prone and typically slow. In the latter, the user can interact with these parameters by means of motor skills which are highly developed. Two specific geoscience application areas will be highlighted. In the first, we have used VR technology to manipulate three-dimensional input parameters, such as the spatial location of injection or production wells in a reservoir simulator. In the second, we demonstrate how VR technology has been used to manipulate visualization tools, such as a tool for computing streamlines via manipulation of a {open_quotes}rake.{close_quotes} The rake is presented to the user in the form of a {open_quotes}virtual well{close_quotes} icon, and provides parameters used by the streamlines algorithm.
Date: June 1, 1996
Creator: Bethel, W.; Jacobsen, J.; Austin, A.; Lederer, M. & Little, T.
Partner: UNT Libraries Government Documents Department