Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-06
..., ``Configuration Management Plans for Digital Computer Software used in Safety Systems of Nuclear Power Plants... Digital Computer Software Used in Safety Systems of Nuclear Power Plants AGENCY: Nuclear Regulatory..., Reviews, and Audits for Digital Computer Software Used in Safety Systems of Nuclear Power Plants.'' This...
'I'm good, but not that good': digitally-skilled young people's identity in computing
NASA Astrophysics Data System (ADS)
Wong, Billy
2016-12-01
Computers and information technology are fast becoming a part of young people's everyday life. However, there remains a difference between the majority who can use computers and the minority who are computer scientists or professionals. Drawing on 32 semi-structured interviews with digitally skilled young people (aged 13-19), we explore their views and aspirations in computing, with a focus on the identities and discourses that these youngsters articulate in relation to this field. Our findings suggest that, even among digitally skilled young people, traditional identities of computing as people who are clever but antisocial still prevail, which can be unattractive for youths, especially girls. Digitally skilled youths identify with computing in different ways and for different reasons. Most enjoy doing computing but few aspired to being a computer person. Implications of our findings for computing education are discussed especially the continued need to broaden identities in computing, even for the digitally skilled.
Synthetic mixed-signal computation in living cells
Rubens, Jacob R.; Selvaggio, Gianluca; Lu, Timothy K.
2016-01-01
Living cells implement complex computations on the continuous environmental signals that they encounter. These computations involve both analogue- and digital-like processing of signals to give rise to complex developmental programs, context-dependent behaviours and homeostatic activities. In contrast to natural biological systems, synthetic biological systems have largely focused on either digital or analogue computation separately. Here we integrate analogue and digital computation to implement complex hybrid synthetic genetic programs in living cells. We present a framework for building comparator gene circuits to digitize analogue inputs based on different thresholds. We then demonstrate that comparators can be predictably composed together to build band-pass filters, ternary logic systems and multi-level analogue-to-digital converters. In addition, we interface these analogue-to-digital circuits with other digital gene circuits to enable concentration-dependent logic. We expect that this hybrid computational paradigm will enable new industrial, diagnostic and therapeutic applications with engineered cells. PMID:27255669
Exploration of operator method digital optical computers for application to NASA
NASA Technical Reports Server (NTRS)
1990-01-01
Digital optical computer design has been focused primarily towards parallel (single point-to-point interconnection) implementation. This architecture is compared to currently developing VHSIC systems. Using demonstrated multichannel acousto-optic devices, a figure of merit can be formulated. The focus is on a figure of merit termed Gate Interconnect Bandwidth Product (GIBP). Conventional parallel optical digital computer architecture demonstrates only marginal competitiveness at best when compared to projected semiconductor implements. Global, analog global, quasi-digital, and full digital interconnects are briefly examined as alternative to parallel digital computer architecture. Digital optical computing is becoming a very tough competitor to semiconductor technology since it can support a very high degree of three dimensional interconnect density and high degrees of Fan-In without capacitive loading effects at very low power consumption levels.
Digital circuits for computer applications: A compilation
NASA Technical Reports Server (NTRS)
1972-01-01
The innovations in this updated series of compilations dealing with electronic technology represent a carefully selected collection of digital circuits which have direct application in computer oriented systems. In general, the circuits have been selected as representative items of each section and have been included on their merits of having universal applications in digital computers and digital data processing systems. As such, they should have wide appeal to the professional engineer and scientist who encounter the fundamentals of digital techniques in their daily activities. The circuits are grouped as digital logic circuits, analog to digital converters, and counters and shift registers.
ERIC Educational Resources Information Center
Onaral, Banu; And Others
This report describes the development of a Drexel University electrical and computer engineering course on digital filter design that used interactive computing and graphics, and was one of three courses in a senior-level sequence on digital signal processing (DSP). Interactive and digital analysis/design routines and the interconnection of these…
The Domain Shared by Computational and Digital Ontology: A Phenomenological Exploration and Analysis
ERIC Educational Resources Information Center
Compton, Bradley Wendell
2009-01-01
The purpose of this dissertation is to explore and analyze a domain of research thought to be shared by two areas of philosophy: computational and digital ontology. Computational ontology is philosophy used to develop information systems also called computational ontologies. Digital ontology is philosophy dealing with our understanding of Being…
Digital and biological computing in organizations.
Kampfner, Roberto R
2002-01-01
Michael Conrad unveiled many of the fundamental characteristics of biological computing. Underlying the behavioral variability and the adaptability of biological systems are these characteristics, including the ability of biological information processing to exploit quantum features at the atomic level, the powerful 3-D pattern recognition capabilities of macromolecules, the computational efficiency, and the ability to support biological function. Among many other things, Conrad formalized and explicated the underlying principles of biological adaptability, characterized the differences between biological and digital computing in terms of a fundamental tradeoff between adaptability and programmability of information processing, and discussed the challenges of interfacing digital computers and human society. This paper is about the encounter of biological and digital computing. The focus is on the nature of the biological information processing infrastructure of organizations and how it can be extended effectively with digital computing. In order to achieve this goal effectively, however, we need to embed properly digital computing into the information processing aspects of human and social behavior and intelligence, which are fundamentally biological. Conrad's legacy provides a firm, strong, and inspiring foundation for this endeavor.
The Correlates of the Digital Divide and Their Impact on College Student Learning
ERIC Educational Resources Information Center
Tien, Flora F.; Fu, Tsu-Tan
2008-01-01
By focusing on two dimensions of the digital divide--computer use and computer knowledge, this study explores four research questions: (1) What are the undergraduates doing with the computers they use at colleges? (2) How do undergraduates perform in regard to computer knowledge and skills? (3) With what is the digital divide among college…
Digital computer technique for setup and checkout of an analog computer
NASA Technical Reports Server (NTRS)
Ambaruch, R.
1968-01-01
Computer program technique, called Analog Computer Check-Out Routine Digitally /ACCORD/, generates complete setup and checkout data for an analog computer. In addition, the correctness of the analog program implementation is validated.
NASA Astrophysics Data System (ADS)
Brown, Gail Laverne
The presence of a digital divide, computer and information technology integration effectiveness, and barriers to continued usage of computer and information technology were investigated. Thirty-four African American and Caucasian American students (17 males and 17 females) in grades 9--11 from 2 Georgia high school science classes were exposed to 30 hours of hands-on computer and information technology skills. The purpose of the exposure was to improve students' computer and information technology skills. Pre-study and post-study skills surveys, and structured interviews were used to compare race, gender, income, grade-level, and age differences with respect to computer usage. A paired t-test and McNemar test determined mean differences between student pre-study and post-study perceived skills levels. The results were consistent with findings of the National Telecommunications and Information Administration (2000) that indicated the presence of a digital divide and digital inclusion. Caucasian American participants were found to have more at-home computer and Internet access than African American participants, indicating that there is a digital divide by ethnicity. Caucasian American females were found to have more computer and Internet access which was an indication of digital inclusion. Sophomores had more at-home computer access and Internet access than other levels indicating digital inclusion. Students receiving regular meals had more computer and Internet access than students receiving free/reduced meals. Older students had more computer and Internet access than younger students. African American males had been using computer and information technology the longest which is an indication of inclusion. The paired t-test and McNemar test revealed significant perceived student increases in all skills levels. Interviews did not reveal any barriers to continued usage of the computer and information technology skills.
Computer Storage and Retrieval of Position - Dependent Data.
1982-06-01
This thesis covers the design of a new digital database system to replace the merged (observation and geographic location) record, one file per cruise...68 "The Digital Data Library System: Library Storage and Retrieval of Digital Geophysical Data" by Robert C. Groan) provided a relatively simple...dependent, ’geophysical’ data. The system is operational on a Digital Equipment Corporation VAX-11/780 computer. Values of measured and computed
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-22
... Digital Computer Software Used in Safety Systems of Nuclear Power Plants AGENCY: Nuclear Regulatory..., ``Verification, Validation, Reviews, and Audits for Digital Computer Software used in Safety Systems of Nuclear... NRC regulations promoting the development of, and compliance with, software verification and...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-22
... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Test Documentation for Digital Computer Software...) is issuing for public comment draft regulatory guide (DG), DG-1207, ``Test Documentation for Digital... practices for test documentation for software and computer systems as described in the Institute of...
Stapleton, Brandon M; Lin, Wei-Shao; Ntounis, Athanasios; Harris, Bryan T; Morton, Dean
2014-09-01
This clinical report demonstrated the use of an implant-supported fixed dental prosthesis fabricated with a contemporary digital approach. The digital diagnostic data acquisition was completed with a digital diagnostic impression with an intraoral scanner and cone-beam computed tomography with a prefabricated universal radiographic template to design a virtual prosthetically driven implant surgical plan. A surgical template fabricated with computer-aided design and computer-aided manufacturing (CAD/CAM) was used to perform computer-guided implant surgery. The definitive digital data were then used to design the definitive CAD/CAM-fabricated fixed dental prosthesis. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Spectroscopic analysis and control
Tate; , James D.; Reed, Christopher J.; Domke, Christopher H.; Le, Linh; Seasholtz, Mary Beth; Weber, Andy; Lipp, Charles
2017-04-18
Apparatus for spectroscopic analysis which includes a tunable diode laser spectrometer having a digital output signal and a digital computer for receiving the digital output signal from the spectrometer, the digital computer programmed to process the digital output signal using a multivariate regression algorithm. In addition, a spectroscopic method of analysis using such apparatus. Finally, a method for controlling an ethylene cracker hydrogenator.
Scalable hybrid computation with spikes.
Sarpeshkar, Rahul; O'Halloran, Micah
2002-09-01
We outline a hybrid analog-digital scheme for computing with three important features that enable it to scale to systems of large complexity: First, like digital computation, which uses several one-bit precise logical units to collectively compute a precise answer to a computation, the hybrid scheme uses several moderate-precision analog units to collectively compute a precise answer to a computation. Second, frequent discrete signal restoration of the analog information prevents analog noise and offset from degrading the computation. And, third, a state machine enables complex computations to be created using a sequence of elementary computations. A natural choice for implementing this hybrid scheme is one based on spikes because spike-count codes are digital, while spike-time codes are analog. We illustrate how spikes afford easy ways to implement all three components of scalable hybrid computation. First, as an important example of distributed analog computation, we show how spikes can create a distributed modular representation of an analog number by implementing digital carry interactions between spiking analog neurons. Second, we show how signal restoration may be performed by recursive spike-count quantization of spike-time codes. And, third, we use spikes from an analog dynamical system to trigger state transitions in a digital dynamical system, which reconfigures the analog dynamical system using a binary control vector; such feedback interactions between analog and digital dynamical systems create a hybrid state machine (HSM). The HSM extends and expands the concept of a digital finite-state-machine to the hybrid domain. We present experimental data from a two-neuron HSM on a chip that implements error-correcting analog-to-digital conversion with the concurrent use of spike-time and spike-count codes. We also present experimental data from silicon circuits that implement HSM-based pattern recognition using spike-time synchrony. We outline how HSMs may be used to perform learning, vector quantization, spike pattern recognition and generation, and how they may be reconfigured.
NASA Technical Reports Server (NTRS)
Neiner, G. H.; Cole, G. L.; Arpasi, D. J.
1972-01-01
Digital computer control of a mixed-compression inlet is discussed. The inlet was terminated with a choked orifice at the compressor face station to dynamically simulate a turbojet engine. Inlet diffuser exit airflow disturbances were used. A digital version of a previously tested analog control system was used for both normal shock and restart control. Digital computer algorithms were derived using z-transform and finite difference methods. Using a sample rate of 1000 samples per second, the digital normal shock and restart controls essentially duplicated the inlet analog computer control results. At a sample rate of 100 samples per second, the control system performed adequately but was less stable.
Sandgren, Buster; Crafoord, Joakim; Garellick, Göran; Carlsson, Lars; Weidenhielm, Lars; Olivecrona, Henrik
2013-10-01
Digital radiographic images in the anterior-posterior and lateral view have been gold standard for evaluation of peri-acetabular osteolysis for patients with an uncemented hip replacement. We compared digital radiographic images and computer tomography in detection of peri-acetabular osteolysis and devised a classification system based on computer tomography. Digital radiographs were compared with computer tomography on 206 hips, with a mean follow up 10 years after surgery. The patients had no clinical signs of osteolysis and none were planned for revision surgery. On digital radiographs, 192 cases had no osteolysis and only 14 cases had osteolysis. When using computer tomography there were 184 cases showing small or large osteolysis and only 22 patients had no osteolysis. A classification system for peri-acetabular osteolysis is proposed based on computer tomography that is easy to use on standard follow up evaluation. Copyright © 2013 Elsevier Inc. All rights reserved.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-22
... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Software Unit Testing for Digital Computer Software...) is issuing for public comment draft regulatory guide (DG), DG-1208, ``Software Unit Testing for Digital Computer Software used in Safety Systems of Nuclear Power Plants.'' The DG-1208 is proposed...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-02
... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Software Unit Testing for Digital Computer Software... revised regulatory guide (RG), revision 1 of RG 1.171, ``Software Unit Testing for Digital Computer Software Used in Safety Systems of Nuclear Power Plants.'' This RG endorses American National Standards...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-24
... Digital Computer-Based Instrumentation and Control Systems.'' This BTP is to be cited as the acceptance criteria for Diversity and Defense-in-Depth in Digital Computer-Based Instrumentation and Control Systems... Evaluation of Diversity and Defense-in-Depth in Digital Computer-Based Instrumentation and Control Systems...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-22
... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Developing Software Life Cycle Processes for Digital... Software Life Cycle Processes for Digital Computer Software used in Safety Systems of Nuclear Power Plants... clarifications, the enhanced consensus practices for developing software life-cycle processes for digital...
Real-time simulation of the TF30-P-3 turbofan engine using a hybrid computer
NASA Technical Reports Server (NTRS)
Szuch, J. R.; Bruton, W. M.
1974-01-01
A real-time, hybrid-computer simulation of the TF30-P-3 turbofan engine was developed. The simulation was primarily analog in nature but used the digital portion of the hybrid computer to perform bivariate function generation associated with the performance of the engine's rotating components. FORTRAN listings and analog patching diagrams are provided. The hybrid simulation was controlled by a digital computer programmed to simulate the engine's standard hydromechanical control. Both steady-state and dynamic data obtained from the digitally controlled engine simulation are presented. Hybrid simulation data are compared with data obtained from a digital simulation provided by the engine manufacturer. The comparisons indicate that the real-time hybrid simulation adequately matches the baseline digital simulation.
Digital Documentation: Using Computers to Create Multimedia Reports.
ERIC Educational Resources Information Center
Speitel, Tom; And Others
1996-01-01
Describes methods for creating integrated multimedia documents using recent advances in print, audio, and video digitization that bring added usefulness to computers as data acquisition, processing, and presentation tools. Discusses advantages of digital documentation. (JRH)
A study of digital holographic filter generation
NASA Technical Reports Server (NTRS)
Calhoun, M.; Ingels, F.
1976-01-01
Problems associated with digital computer generation of holograms are discussed along with a criteria for producing optimum digital holograms. This criteria revolves around amplitude resolution and spatial frequency limitations induced by the computer and plotter process.
Digital receiver study and implementation
NASA Technical Reports Server (NTRS)
Fogle, D. A.; Lee, G. M.; Massey, J. C.
1972-01-01
Computer software was developed which makes it possible to use any general purpose computer with A/D conversion capability as a PSK receiver for low data rate telemetry processing. Carrier tracking, bit synchronization, and matched filter detection are all performed digitally. To aid in the implementation of optimum computer processors, a study of general digital processing techniques was performed which emphasized various techniques for digitizing general analog systems. In particular, the phase-locked loop was extensively analyzed as a typical non-linear communication element. Bayesian estimation techniques for PSK demodulation were studied. A hardware implementation of the digital Costas loop was developed.
Automatic Mexican sign language and digits recognition using normalized central moments
NASA Astrophysics Data System (ADS)
Solís, Francisco; Martínez, David; Espinosa, Oscar; Toxqui, Carina
2016-09-01
This work presents a framework for automatic Mexican sign language and digits recognition based on computer vision system using normalized central moments and artificial neural networks. Images are captured by digital IP camera, four LED reflectors and a green background in order to reduce computational costs and prevent the use of special gloves. 42 normalized central moments are computed per frame and used in a Multi-Layer Perceptron to recognize each database. Four versions per sign and digit were used in training phase. 93% and 95% of recognition rates were achieved for Mexican sign language and digits respectively.
Conversion of cardiac performance data in analog form for digital computer entry
NASA Technical Reports Server (NTRS)
Miller, R. L.
1972-01-01
A system is presented which will reduce analog cardiac performance data and convert the results to digital form for direct entry into a commercial time-shared computer. Circuits are discussed which perform the measurement and digital conversion of instantaneous systolic and diastolic parameters from the analog blood pressure waveform. Digital averaging over a selected number of heart cycles is performed on these measurements, as well as those of flow and heart rate. The determination of average cardiac output and peripheral resistance, including trends, is the end result after processing by digital computer.
NASA Technical Reports Server (NTRS)
Tranter, W. H.; Turner, M. D.
1977-01-01
Techniques are developed to estimate power gain, delay, signal-to-noise ratio, and mean square error in digital computer simulations of lowpass and bandpass systems. The techniques are applied to analog and digital communications. The signal-to-noise ratio estimates are shown to be maximum likelihood estimates in additive white Gaussian noise. The methods are seen to be especially useful for digital communication systems where the mapping from the signal-to-noise ratio to the error probability can be obtained. Simulation results show the techniques developed to be accurate and quite versatile in evaluating the performance of many systems through digital computer simulation.
Digital video technology, today and tomorrow
NASA Astrophysics Data System (ADS)
Liberman, J.
1994-10-01
Digital video is probably computing's fastest moving technology today. Just three years ago, the zenith of digital video technology on the PC was the successful marriage of digital text and graphics with analog audio and video by means of expensive analog laser disc players and video overlay boards. The state of the art involves two different approaches to fully digital video on computers: hardware-assisted and software-only solutions.
Digital pathology in nephrology clinical trials, research, and pathology practice.
Barisoni, Laura; Hodgin, Jeffrey B
2017-11-01
In this review, we will discuss (i) how the recent advancements in digital technology and computational engineering are currently applied to nephropathology in the setting of clinical research, trials, and practice; (ii) the benefits of the new digital environment; (iii) how recognizing its challenges provides opportunities for transformation; and (iv) nephropathology in the upcoming era of kidney precision and predictive medicine. Recent studies highlighted how new standardized protocols facilitate the harmonization of digital pathology database infrastructure and morphologic, morphometric, and computer-aided quantitative analyses. Digital pathology enables robust protocols for clinical trials and research, with the potential to identify previously underused or unrecognized clinically useful parameters. The integration of digital pathology with molecular signatures is leading the way to establishing clinically relevant morpho-omic taxonomies of renal diseases. The introduction of digital pathology in clinical research and trials, and the progressive implementation of the modern software ecosystem, opens opportunities for the development of new predictive diagnostic paradigms and computer-aided algorithms, transforming the practice of renal disease into a modern computational science.
Utilization of KSC Present Broadband Communications Data System for Digital Video Services
NASA Technical Reports Server (NTRS)
Andrawis, Alfred S.
2002-01-01
This report covers a visibility study of utilizing present KSC broadband communications data system (BCDS) for digital video services. Digital video services include compressed digital TV delivery and video-on-demand. Furthermore, the study examines the possibility of providing interactive video on demand to desktop personal computers via KSC computer network.
Digital Tools: Enhancing Painting Skills among Malaysian Secondary School Students
ERIC Educational Resources Information Center
Samah, Azimah A.; Putih, Abu Talib; Hussin, Zaharah
2016-01-01
Digital tools refer to software applications in the production of artworks particularly in painting. Digital art work is materialized by using computers, software and a combination of computer peripherals such as tablet support. With the aid of electronic equipment, digital artists manipulate pixels or coloring with light to compose the work and…
ERIC Educational Resources Information Center
van Langeveld, Mark Christensen
2009-01-01
Digital character production courses have traditionally been taught in art departments. The digital character production course at the University of Utah is centered, drawing uniformly from art and engineering disciplines. Its design has evolved to include a synergy of computer science, functional art and human anatomy. It gives students an…
Utilization of KSC Present Broadband Communications Data System For Digital Video Services
NASA Technical Reports Server (NTRS)
Andrawis, Alfred S.
2001-01-01
This report covers a visibility study of utilizing present KSC broadband communications data system (BCDS) for digital video services. Digital video services include compressed digital TV delivery and video-on-demand. Furthermore, the study examines the possibility of providing interactive video on demand to desktop personal computers via KSC computer network.
Lewis hybrid computing system, users manual
NASA Technical Reports Server (NTRS)
Bruton, W. M.; Cwynar, D. S.
1979-01-01
The Lewis Research Center's Hybrid Simulation Lab contains a collection of analog, digital, and hybrid (combined analog and digital) computing equipment suitable for the dynamic simulation and analysis of complex systems. This report is intended as a guide to users of these computing systems. The report describes the available equipment' and outlines procedures for its use. Particular is given to the operation of the PACER 100 digital processor. System software to accomplish the usual digital tasks such as compiling, editing, etc. and Lewis-developed special purpose software are described.
The use of self-organising maps for anomalous behaviour detection in a digital investigation.
Fei, B K L; Eloff, J H P; Olivier, M S; Venter, H S
2006-10-16
The dramatic increase in crime relating to the Internet and computers has caused a growing need for digital forensics. Digital forensic tools have been developed to assist investigators in conducting a proper investigation into digital crimes. In general, the bulk of the digital forensic tools available on the market permit investigators to analyse data that has been gathered from a computer system. However, current state-of-the-art digital forensic tools simply cannot handle large volumes of data in an efficient manner. With the advent of the Internet, many employees have been given access to new and more interesting possibilities via their desktop. Consequently, excessive Internet usage for non-job purposes and even blatant misuse of the Internet have become a problem in many organisations. Since storage media are steadily growing in size, the process of analysing multiple computer systems during a digital investigation can easily consume an enormous amount of time. Identifying a single suspicious computer from a set of candidates can therefore reduce human processing time and monetary costs involved in gathering evidence. The focus of this paper is to demonstrate how, in a digital investigation, digital forensic tools and the self-organising map (SOM)--an unsupervised neural network model--can aid investigators to determine anomalous behaviours (or activities) among employees (or computer systems) in a far more efficient manner. By analysing the different SOMs (one for each computer system), anomalous behaviours are identified and investigators are assisted to conduct the analysis more efficiently. The paper will demonstrate how the easy visualisation of the SOM enhances the ability of the investigators to interpret and explore the data generated by digital forensic tools so as to determine anomalous behaviours.
System design and implementation of digital-image processing using computational grids
NASA Astrophysics Data System (ADS)
Shen, Zhanfeng; Luo, Jiancheng; Zhou, Chenghu; Huang, Guangyu; Ma, Weifeng; Ming, Dongping
2005-06-01
As a special type of digital image, remotely sensed images are playing increasingly important roles in our daily lives. Because of the enormous amounts of data involved, and the difficulties of data processing and transfer, an important issue for current computer and geo-science experts is developing internet technology to implement rapid remotely sensed image processing. Computational grids are able to solve this problem effectively. These networks of computer workstations enable the sharing of data and resources, and are used by computer experts to solve imbalances of network resources and lopsided usage. In China, computational grids combined with spatial-information-processing technology have formed a new technology: namely, spatial-information grids. In the field of remotely sensed images, spatial-information grids work more effectively for network computing, data processing, resource sharing, task cooperation and so on. This paper focuses mainly on the application of computational grids to digital-image processing. Firstly, we describe the architecture of digital-image processing on the basis of computational grids, its implementation is then discussed in detail with respect to the technology of middleware. The whole network-based intelligent image-processing system is evaluated on the basis of the experimental analysis of remotely sensed image-processing tasks; the results confirm the feasibility of the application of computational grids to digital-image processing.
Study of a hybrid multispectral processor
NASA Technical Reports Server (NTRS)
Marshall, R. E.; Kriegler, F. J.
1973-01-01
A hybrid processor is described offering enough handling capacity and speed to process efficiently the large quantities of multispectral data that can be gathered by scanner systems such as MSDS, SKYLAB, ERTS, and ERIM M-7. Combinations of general-purpose and special-purpose hybrid computers were examined to include both analog and digital types as well as all-digital configurations. The current trend toward lower costs for medium-scale digital circuitry suggests that the all-digital approach may offer the better solution within the time frame of the next few years. The study recommends and defines such a hybrid digital computing system in which both special-purpose and general-purpose digital computers would be employed. The tasks of recognizing surface objects would be performed in a parallel, pipeline digital system while the tasks of control and monitoring would be handled by a medium-scale minicomputer system. A program to design and construct a small, prototype, all-digital system has been started.
Classified one-step high-radix signed-digit arithmetic units
NASA Astrophysics Data System (ADS)
Cherri, Abdallah K.
1998-08-01
High-radix number systems enable higher information storage density, less complexity, fewer system components, and fewer cascaded gates and operations. A simple one-step fully parallel high-radix signed-digit arithmetic is proposed for parallel optical computing based on new joint spatial encodings. This reduces hardware requirements and improves throughput by reducing the space-bandwidth produce needed. The high-radix signed-digit arithmetic operations are based on classifying the neighboring input digit pairs into various groups to reduce the computation rules. A new joint spatial encoding technique is developed to present both the operands and the computation rules. This technique increases the spatial bandwidth product of the spatial light modulators of the system. An optical implementation of the proposed high-radix signed-digit arithmetic operations is also presented. It is shown that our one-step trinary signed-digit and quaternary signed-digit arithmetic units are much simpler and better than all previously reported high-radix signed-digit techniques.
NASA Technical Reports Server (NTRS)
Ladson, C. L.; Brooks, Cuyler W., Jr.
1975-01-01
A computer program developed to calculate the ordinates and surface slopes of any thickness, symmetrical or cambered NACA airfoil of the 4-digit, 4-digit modified, 5-digit, and 16-series airfoil families is presented. The program produces plots of the airfoil nondimensional ordinates and a punch card output of ordinates in the input format of a readily available program for determining the pressure distributions of arbitrary airfoils in subsonic potential viscous flow.
Evaluation of Digital Technology and Software Use among Business Education Teachers
ERIC Educational Resources Information Center
Ellis, Richard S.; Okpala, Comfort O.
2004-01-01
Digital video cameras are part of the evolution of multimedia digital products that have positive applications for educators, students, and industry. Multimedia digital video can be utilized by any personal computer and it allows the user to control, combine, and manipulate different types of media, such as text, sound, video, computer graphics,…
Flight test validation of a design procedure for digital autopilots
NASA Technical Reports Server (NTRS)
Bryant, W. H.
1983-01-01
Commercially available general aviation autopilots are currently in transition from an analogue circuit system to a computer implemented digital flight control system. Well known advantages of the digital autopilot include enhanced modes, self-test capacity, fault detection, and greater computational capacity. A digital autopilot's computational capacity can be used to full advantage by increasing the sophistication of the digital autopilot's chief function, stability and control. NASA's Langley Research Center has been pursuing the development of direct digital design tools for aircraft stabilization systems for several years. This effort has most recently been directed towards the development and realization of multi-mode digital autopilots for GA aircraft, conducted under a SPIFR-related program called the General Aviation Terminal Operations Research (GATOR) Program. This presentation focuses on the implementation and testing of a candidate multi-mode autopilot designed using these newly developed tools.
1991-03-31
I AD-A232 768 I Annual Report Analysis of Polarizing Optical Systems for Digital Optical Computing with I ’ Symmetric Self Electrooptic Devices I To...TTU AND SuSiIU S. PUNDIN mUMBERS Polarizing Optical Systems for Digital Optical Computing with Symmetric Self Electrooptic Devices AFOSR-89-0542 C...UTION COO$ UNLIMITED 13. ABSTRACT (MAxnum00woUw Two architectural approaches have dominated the field of optical computing . The first appAch uses
ERIC Educational Resources Information Center
Ba, Harouna; Tally, Bill; Tsikalas, Kallen
The EDC (Educational Development Center) Center for Children and Technology (CCT) and Computers for Youth (CFY) completed a 1-year comparative study of children's use of computers in low- and middle-income homes. The study explores the digital divide as a literacy issue, rather than merely a technical one. Digital literacy is defined as a set of…
Digital data storage systems, computers, and data verification methods
Groeneveld, Bennett J.; Austad, Wayne E.; Walsh, Stuart C.; Herring, Catherine A.
2005-12-27
Digital data storage systems, computers, and data verification methods are provided. According to a first aspect of the invention, a computer includes an interface adapted to couple with a dynamic database; and processing circuitry configured to provide a first hash from digital data stored within a portion of the dynamic database at an initial moment in time, to provide a second hash from digital data stored within the portion of the dynamic database at a subsequent moment in time, and to compare the first hash and the second hash.
NASA Astrophysics Data System (ADS)
Cunningham, Sally Jo
The current crop of digital libraries for the computing community are strongly grounded in the conventional library paradigm: they provide indexes to support searching of collections of research papers. As such, these digital libraries are relatively impoverished; the present computing digital libraries omit many of the documents and resources that are currently available to computing researchers, and offer few browsing structures. These computing digital libraries were built 'top down': the resources and collection contents are forced to fit an existing digital library architecture. A 'bottom up' approach to digital library development would begin with an investigation of a community's information needs and available documents, and then design a library to organize those documents in such a way as to fulfill the community's needs. The 'home grown', informal information resources developed by and for the machine learning community are examined as a case study, to determine the types of information and document organizations 'native' to this group of researchers. The insights gained in this type of case study can be used to inform construction of a digital library tailored to this community.
NASA Astrophysics Data System (ADS)
Cook, Perry R.
This chapter covers algorithms, technologies, computer languages, and systems for computer music. Computer music involves the application of computers and other digital/electronic technologies to music composition, performance, theory, history, and the study of perception. The field combines digital signal processing, computational algorithms, computer languages, hardware and software systems, acoustics, psychoacoustics (low-level perception of sounds from the raw acoustic signal), and music cognition (higher-level perception of musical style, form, emotion, etc.).
Arunyanak, Sirikarn P; Harris, Bryan T; Grant, Gerald T; Morton, Dean; Lin, Wei-Shao
2016-07-01
This report describes a digital approach for computer-guided surgery and immediate provisionalization in a partially edentulous patient. With diagnostic data obtained from cone-beam computed tomography and intraoral digital diagnostic scans, a digital pathway of virtual diagnostic waxing, a virtual prosthetically driven surgical plan, a computer-aided design and computer-aided manufacturing (CAD/CAM) surgical template, and implant-supported screw-retained interim restorations were realized with various open-architecture CAD/CAM systems. The optional CAD/CAM diagnostic casts with planned implant placement were also additively manufactured to facilitate preoperative inspection of the surgical template and customization of the CAD/CAM-fabricated interim restorations. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Optical memories in digital computing
NASA Technical Reports Server (NTRS)
Alford, C. O.; Gaylord, T. K.
1979-01-01
High capacity optical memories with relatively-high data-transfer rate and multiport simultaneous access capability may serve as basis for new computer architectures. Several computer structures that might profitably use memories are: a) simultaneous record-access system, b) simultaneously-shared memory computer system, and c) parallel digital processing structure.
Two-dimensional radiant energy array computers and computing devices
NASA Technical Reports Server (NTRS)
Schaefer, D. H.; Strong, J. P., III (Inventor)
1976-01-01
Two dimensional digital computers and computer devices operate in parallel on rectangular arrays of digital radiant energy optical signal elements which are arranged in ordered rows and columns. Logic gate devices receive two input arrays and provide an output array having digital states dependent only on the digital states of the signal elements of the two input arrays at corresponding row and column positions. The logic devices include an array of photoconductors responsive to at least one of the input arrays for either selectively accelerating electrons to a phosphor output surface, applying potentials to an electroluminescent output layer, exciting an array of discrete radiant energy sources, or exciting a liquid crystal to influence crystal transparency or reflectivity.
Will the digital computer transform classical mathematics?
Rotman, Brian
2003-08-15
Mathematics and machines have influenced each other for millennia. The advent of the digital computer introduced a powerfully new element that promises to transform the relation between them. This paper outlines the thesis that the effect of the digital computer on mathematics, already widespread, is likely to be radical and far-reaching. To articulate this claim, an abstract model of doing mathematics is introduced based on a triad of actors of which one, the 'agent', corresponds to the function performed by the computer. The model is used to frame two sorts of transformation. The first is pragmatic and involves the alterations and progressive colonization of the content and methods of enquiry of various mathematical fields brought about by digital methods. The second is conceptual and concerns a fundamental antagonism between the infinity enshrined in classical mathematics and physics (continuity, real numbers, asymptotic definitions) and the inherently real and material limit of processes associated with digital computation. An example which lies in the intersection of classical mathematics and computer science, the P=NP problem, is analysed in the light of this latter issue.
[Overall digitalization: leading innovation of endodontics in big data era].
Ling, J Q
2016-04-09
In big data era, digital technologies bring great challenges and opportunities to modern stomatology. The applications of digital technologies, such as cone-beam CT(CBCT), computer aided design,(CAD)and computer aided manufacture(CAM), 3D printing and digital approaches for education , provide new concepts and patterns to the treatment and study of endodontic diseases. This review provides an overview of the application and prospect of commonly used digital technologies in the development of endodontics.
Comparison of digital controllers used in magnetic suspension and balance systems
NASA Technical Reports Server (NTRS)
Kilgore, William A.
1990-01-01
Dynamic systems that were once controlled by analog circuits are now controlled by digital computers. Presented is a comparison of the digital controllers presently used with magnetic suspension and balance systems. The overall responses of the systems are compared using a computer simulation of the magnetic suspension and balance system and the digital controllers. The comparisons include responses to both simulated force and position inputs. A preferred digital controller is determined from the simulated responses.
Digital Workflow for Computer-Guided Implant Surgery in Edentulous Patients: A Case Report.
Oh, Ji-Hyeon; An, Xueyin; Jeong, Seung-Mi; Choi, Byung-Ho
2017-12-01
The purpose of this article was to describe a fully digital workflow used to perform computer-guided flapless implant placement in an edentulous patient without the use of conventional impressions, models, or a radiographic guide. Digital data for the workflow were acquired using an intraoral scanner and cone-beam computed tomography (CBCT). The image fusion of the intraoral scan data and CBCT data was performed by matching resin markers placed in the patient's mouth. The definitive digital data were used to design a prosthetically driven implant position, surgical template, and computer-aided design and computer-aided manufacturing fabricated fixed dental prosthesis. The authors believe this is the first published case describing such a technique in computer-guided flapless implant surgery for edentulous patients. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
On the Rapid Computation of Various Polylogarithmic Constants
NASA Technical Reports Server (NTRS)
Bailey, David H.; Borwein, Peter; Plouffe, Simon
1996-01-01
We give algorithms for the computation of the d-th digit of certain transcendental numbers in various bases. These algorithms can be easily implemented (multiple precision arithmetic is not needed), require virtually no memory, and feature run times that scale nearly linearly with the order of the digit desired. They make it feasible to compute, for example, the billionth binary digit of log(2) or pi on a modest workstation in a few hours run time. We demonstrate this technique by computing the ten billionth hexadecimal digit of pi, the billionth hexadecimal digits of pi-squared, log(2) and log-squared(2), and the ten billionth decimal digit of log(9/10). These calculations rest on the observation that very special types of identities exist for certain numbers like pi, pi-squared, log(2) and log-squared(2). These are essentially polylogarithmic ladders in an integer base. A number of these identities that we derive in this work appear to be new, for example a critical identity for pi.
Matrix-vector multiplication using digital partitioning for more accurate optical computing
NASA Technical Reports Server (NTRS)
Gary, C. K.
1992-01-01
Digital partitioning offers a flexible means of increasing the accuracy of an optical matrix-vector processor. This algorithm can be implemented with the same architecture required for a purely analog processor, which gives optical matrix-vector processors the ability to perform high-accuracy calculations at speeds comparable with or greater than electronic computers as well as the ability to perform analog operations at a much greater speed. Digital partitioning is compared with digital multiplication by analog convolution, residue number systems, and redundant number representation in terms of the size and the speed required for an equivalent throughput as well as in terms of the hardware requirements. Digital partitioning and digital multiplication by analog convolution are found to be the most efficient alogrithms if coding time and hardware are considered, and the architecture for digital partitioning permits the use of analog computations to provide the greatest throughput for a single processor.
Digitized adiabatic quantum computing with a superconducting circuit.
Barends, R; Shabani, A; Lamata, L; Kelly, J; Mezzacapo, A; Las Heras, U; Babbush, R; Fowler, A G; Campbell, B; Chen, Yu; Chen, Z; Chiaro, B; Dunsworth, A; Jeffrey, E; Lucero, E; Megrant, A; Mutus, J Y; Neeley, M; Neill, C; O'Malley, P J J; Quintana, C; Roushan, P; Sank, D; Vainsencher, A; Wenner, J; White, T C; Solano, E; Neven, H; Martinis, John M
2016-06-09
Quantum mechanics can help to solve complex problems in physics and chemistry, provided they can be programmed in a physical device. In adiabatic quantum computing, a system is slowly evolved from the ground state of a simple initial Hamiltonian to a final Hamiltonian that encodes a computational problem. The appeal of this approach lies in the combination of simplicity and generality; in principle, any problem can be encoded. In practice, applications are restricted by limited connectivity, available interactions and noise. A complementary approach is digital quantum computing, which enables the construction of arbitrary interactions and is compatible with error correction, but uses quantum circuit algorithms that are problem-specific. Here we combine the advantages of both approaches by implementing digitized adiabatic quantum computing in a superconducting system. We tomographically probe the system during the digitized evolution and explore the scaling of errors with system size. We then let the full system find the solution to random instances of the one-dimensional Ising problem as well as problem Hamiltonians that involve more complex interactions. This digital quantum simulation of the adiabatic algorithm consists of up to nine qubits and up to 1,000 quantum logic gates. The demonstration of digitized adiabatic quantum computing in the solid state opens a path to synthesizing long-range correlations and solving complex computational problems. When combined with fault-tolerance, our approach becomes a general-purpose algorithm that is scalable.
ERIC Educational Resources Information Center
Morris, Jonathan Padraig
2011-01-01
Attempts to bridge the Digital Divide have seen vast investment in Information Communication Technology in schools. In the United Kingdom, the Computers for Pupils initiative has invested 60 million British Pounds of funds to help some of the most disadvantaged secondary school pupils by putting a computer in their home. This paper charts and…
1981-11-30
COMPUTER PROGRAM USER’S MANUAL FOR FIREFINDER DIGITAL TOPOGRAPHIC DATA VERIFICATION LIBRARY DUBBING SYSTEM 30 NOVEMBER 1981 by: Marie Ceres Leslie R...Library .............................. 1-2 1.2.3 Dubbing .......................... 1-2 1.3 Library Process Overview ..................... 1-3 2 LIBRARY...RPOSE AND SCOPE This manual describes the computer programs for the FIREFINDER Digital Topographic Data Veri fication-Library- Dubbing System (FFDTDVLDS
Computer Instructional Aids for Undergraduate Control Education. 1978 Edition.
ERIC Educational Resources Information Center
Volz, Richard A.; And Others
This work represents the development of computer tools for undergraduate students. Emphasis is on automatic control theory using hybrid and digital computation. The routine calculations of control system analysis are presented as students would use them on the University of Michigan's central digital computer and the time-shared graphic terminals…
Test and control computer user's guide for a digital beam former test system
NASA Technical Reports Server (NTRS)
Alexovich, Robert E.; Mallasch, Paul G.
1992-01-01
A Digital Beam Former Test System was developed to determine the effects of noise, interferers and distortions, and digital implementations of beam forming as applied to the Tracking and Data Relay Satellite 2 (TDRS 2) architectures. The investigation of digital beam forming with application to TDRS 2 architectures, as described in TDRS 2 advanced concept design studies, was conducted by the NASA/Lewis Research Center for NASA/Goddard Space Flight Center. A Test and Control Computer (TCC) was used as the main controlling element of the digital Beam Former Test System. The Test and Control Computer User's Guide for a Digital Beam Former Test System provides an organized description of the Digital Beam Former Test System commands. It is written for users who wish to conduct tests of the Digital Beam forming Test processor using the TCC. The document describes the function, use, and syntax of the TCC commands available to the user while summarizing and demonstrating the use of the commands wtihin DOS batch files.
An all digital phase locked loop for FM demodulation.
NASA Technical Reports Server (NTRS)
Greco, J.; Garodnick, J.; Schilling, D. L.
1972-01-01
A phase-locked loop designed with all-digital circuitry which avoids certain problems, and a digital voltage controlled oscillator algorithm are described. The system operates synchronously and performs all required digital calculations within one sampling period, thereby performing as a real-time special-purpose computer. The SNR ratio is computed for frequency offsets and sinusoidal modulation, and experimental results verify the theoretical calculations.
28 CFR 75.6 - Statement describing location of books and records.
Code of Federal Regulations, 2011 CFR
2011-07-01
...- or computer-manipulated image, digital image, or picture, or other matter (including but not limited... the book, magazine, periodical, film, videotape, digitally- or computer-manipulated image, digital image, picture, or other matter to affix the statement. In this paragraph, the term “copy” includes...
ERIC Educational Resources Information Center
Lanham, Richard A.
1989-01-01
Traces the early history of the electronic digital computer and the viewpoints held concerning the computer from its inception to its present status. Highlights three key words ("mimesis,""topic," and "decorum") to develop the rhetoricality of the personal computer as a communications device. (KEH)
ERIC Educational Resources Information Center
Hill, Linda L.; Crosier, Scott J.; Smith, Terrence R.; Goodchild, Michael; Iannella, Renato; Erickson, John S.; Reich, Vicky; Rosenthal, David S. H.
2001-01-01
Includes five articles. Topics include requirements for a content standard to describe computational models; architectures for digital rights management systems; access control for digital information objects; LOCKSS (Lots of Copies Keep Stuff Safe) that allows libraries to run Web caches for specific journals; and a Web site from the U.S.…
MDA-image: an environment of networked desktop computers for teleradiology/pathology.
Moffitt, M E; Richli, W R; Carrasco, C H; Wallace, S; Zimmerman, S O; Ayala, A G; Benjamin, R S; Chee, S; Wood, P; Daniels, P
1991-04-01
MDA-Image, a project of The University of Texas M. D. Anderson Cancer Center, is an environment of networked desktop computers for teleradiology/pathology. Radiographic film is digitized with a film scanner and histopathologic slides are digitized using a red, green, and blue (RGB) video camera connected to a microscope. Digitized images are stored on a data server connected to the institution's computer communication network (Ethernet) and can be displayed from authorized desktop computers connected to Ethernet. Images are digitized for cases presented at the Bone Tumor Management Conference, a multidisciplinary conference in which treatment options are discussed among clinicians, surgeons, radiologists, pathologists, radiotherapists, and medical oncologists. These radiographic and histologic images are shown on a large screen computer monitor during the conference. They are available for later review for follow-up or representation.
Divergence of Digital World of Teachers
ERIC Educational Resources Information Center
Uzunboylu, Huseyin; Tuncay, Nazime
2010-01-01
There exists great diversity in the teachers' digital world. Teachers are being discriminated based on numerous educational gaps. This paper seeks to assess the extent of the digital divide among the North Cyprus vocational teachers along the four axes: age, Internet access, computer access, and performance (computing knowledge/experience). A…
A computer program for obtaining airplane configuration plots from digital Datcom input data
NASA Technical Reports Server (NTRS)
Roy, M. L.; Sliwa, S. M.
1983-01-01
A computer program is described which reads the input file for the Stability and Control Digital Datcom program and generates plots from the aircraft configuration data. These plots can be used to verify the geometric input data to the Digital Datcom program. The program described interfaces with utilities available for plotting aircraft configurations by creating a file from the Digital Datcom input data.
1982-01-29
N - Nw .VA COMPUTER PROGRAM USER’S MANUAL FOR . 0FIREFINDER DIGITAL TOPOGRAPHIC DATA VERIFICATION LIBRARY DUBBING SYSTEM VOLUME II DUBBING 29 JANUARY...Digital Topographic Data Verification Library Dubbing System, Volume II, Dubbing 6. PERFORMING ORG. REPORT NUMER 7. AUTHOR(q) S. CONTRACT OR GRANT...Software Library FIREFINDER Dubbing 20. ABSTRACT (Continue an revWee *Ide II necessary end identify by leek mauber) PThis manual describes the computer
ECDSA B-233 with Precomputation 1.0 Beta Version
DOE Office of Scientific and Technical Information (OSTI.GOV)
Draelos, Timothy; Schroeppel, Richard; Schoeneman, Barry
2009-12-11
This software, written in C, performs two functions: 1) the generation of digital signatures using ECDSA with the B-233 curve and a table of precomputed values, and 2) the generation and encryption of a table of precomputed values to support the generation of many digital signatures. The computationally expensive operations of ECDSA signature generation are precomputed, stored in a table, and protected with AES encryption. This allows digital signatures to be generated in low-power, computationally-constrained environments, such as are often found in non-proliferation monitoring applications. The encrypted, precomputed table and digital signature generation software are used to provide public keymore » data authentication for sensor data. When digital data is presented for signing, a set of values from the table is decrypted and used to generate an ECDSA digital signatureThis software, written in C, performs two functions: 1) the generation of digital signatures using ECDSA with the B-233 curve and a table of precomputed values, and 2) the generation and encryption of a table of precomputed values to support the generation of many digital signatures. The computationally expensive operations of ECDSA signature generation are precomputed, stored in a table, and protected with AES encryption. This allows digital signatures to be generated in low-power, computationally-constrained environments, such as are often found in non-proliferation monitoring applications. The encrypted, precomputed table and digital signature generation software are used to provide public key data authentication for sensor data. When digital data is presented for signing, a set of values from the table is decrypted and used to generate an ECDSA digital signature« less
ERIC Educational Resources Information Center
Anderson, Greg; And Others
1996-01-01
Describes the Computer Science Technical Report Project, one of the earliest investigations into the system engineering of digital libraries which pioneered multiinstitutional collaborative research into technical, social, and legal issues related to the development and implementation of a large, heterogeneous, distributed digital library. (LRW)
NASA Technical Reports Server (NTRS)
Giddings, L.; Boston, S.
1976-01-01
A method for digitizing zone maps is presented, starting with colored images and producing a final one-channel digitized tape. This method automates the work previously done interactively on the Image-100 and Data Analysis System computers of the Johnson Space Center (JSC) Earth Observations Division (EOD). A color-coded map was digitized through color filters on a scanner to form a digital tape in LARSYS-2 or JSC Universal format. The taped image was classified by the EOD LARSYS program on the basis of training fields included in the image. Numerical values were assigned to all pixels in a given class, and the resulting coded zone map was written on a LARSYS or Universal tape. A unique spatial filter option permitted zones to be made homogeneous and edges of zones to be abrupt transitions from one zone to the next. A zoom option allowed the output image to have arbitrary dimensions in terms of number of lines and number of samples on a line. Printouts of the computer program are given and the images that were digitized are shown.
Two schemes for rapid generation of digital video holograms using PC cluster
NASA Astrophysics Data System (ADS)
Park, Hanhoon; Song, Joongseok; Kim, Changseob; Park, Jong-Il
2017-12-01
Computer-generated holography (CGH), which is a process of generating digital holograms, is computationally expensive. Recently, several methods/systems of parallelizing the process using graphic processing units (GPUs) have been proposed. Indeed, use of multiple GPUs or a personal computer (PC) cluster (each PC with GPUs) enabled great improvements in the process speed. However, extant literature has less often explored systems involving rapid generation of multiple digital holograms and specialized systems for rapid generation of a digital video hologram. This study proposes a system that uses a PC cluster and is able to more efficiently generate a video hologram. The proposed system is designed to simultaneously generate multiple frames and accelerate the generation by parallelizing the CGH computations across a number of frames, as opposed to separately generating each individual frame while parallelizing the CGH computations within each frame. The proposed system also enables the subprocesses for generating each frame to execute in parallel through multithreading. With these two schemes, the proposed system significantly reduced the data communication time for generating a digital hologram when compared with that of the state-of-the-art system.
Universe creation on a computer
NASA Astrophysics Data System (ADS)
McCabe, Gordon
The purpose of this paper is to provide an account of the epistemology and metaphysics of universe creation on a computer. The paper begins with F.J. Tipler's argument that our experience is indistinguishable from the experience of someone embedded in a perfect computer simulation of our own universe, hence we cannot know whether or not we are part of such a computer program ourselves. Tipler's argument is treated as a special case of epistemological scepticism, in a similar vein to 'brain-in-a-vat' arguments. It is argued that Tipler's hypothesis that our universe is a program running on a digital computer in another universe, generates empirical predictions, and is therefore a falsifiable hypothesis. The computer program hypothesis is also treated as a hypothesis about what exists beyond the physical world, and is compared with Kant's metaphysics of noumena. It is argued that if our universe is a program running on a digital computer, then our universe must have compact spatial topology, and the possibilities of observationally testing this prediction are considered. The possibility of testing the computer program hypothesis with the value of the density parameter Ω0 is also analysed. The informational requirements for a computer to represent a universe exactly and completely are considered. Consequent doubt is thrown upon Tipler's claim that if a hierarchy of computer universes exists, we would not be able to know which 'level of implementation' our universe exists at. It is then argued that a digital computer simulation of a universe, or any other physical system, does not provide a realisation of that universe or system. It is argued that a digital computer simulation of a physical system is not objectively related to that physical system, and therefore cannot exist as anything else other than a physical process occurring upon the components of the computer. It is concluded that Tipler's sceptical hypothesis, and a related hypothesis from Bostrom, cannot be true: it is impossible that our own experience is indistinguishable from the experience of somebody embedded in a digital computer simulation because it is impossible for anybody to be embedded in a digital computer simulation.
Gimpel, Charlotte; Kain, Renate; Laurinavicius, Arvydas; Bueno, Gloria; Zeng, Caihong; Liu, Zhihong; Schaefer, Franz; Kretzler, Matthias; Holzman, Lawrence B.; Hewitt, Stephen M.
2017-01-01
Abstract The introduction of digital pathology to nephrology provides a platform for the development of new methodologies and protocols for visual, morphometric and computer-aided assessment of renal biopsies. Application of digital imaging to pathology made substantial progress over the past decade; it is now in use for education, clinical trials and translational research. Digital pathology evolved as a valuable tool to generate comprehensive structural information in digital form, a key prerequisite for achieving precision pathology for computational biology. The application of this new technology on an international scale is driving novel methods for collaborations, providing unique opportunities but also challenges. Standardization of methods needs to be rigorously evaluated and applied at each step, from specimen processing to scanning, uploading into digital repositories, morphologic, morphometric and computer-aided assessment, data collection and analysis. In this review, we discuss the status and opportunities created by the application of digital imaging to precision nephropathology, and present a vision for the near future. PMID:28584625
Barisoni, Laura; Gimpel, Charlotte; Kain, Renate; Laurinavicius, Arvydas; Bueno, Gloria; Zeng, Caihong; Liu, Zhihong; Schaefer, Franz; Kretzler, Matthias; Holzman, Lawrence B; Hewitt, Stephen M
2017-04-01
The introduction of digital pathology to nephrology provides a platform for the development of new methodologies and protocols for visual, morphometric and computer-aided assessment of renal biopsies. Application of digital imaging to pathology made substantial progress over the past decade; it is now in use for education, clinical trials and translational research. Digital pathology evolved as a valuable tool to generate comprehensive structural information in digital form, a key prerequisite for achieving precision pathology for computational biology. The application of this new technology on an international scale is driving novel methods for collaborations, providing unique opportunities but also challenges. Standardization of methods needs to be rigorously evaluated and applied at each step, from specimen processing to scanning, uploading into digital repositories, morphologic, morphometric and computer-aided assessment, data collection and analysis. In this review, we discuss the status and opportunities created by the application of digital imaging to precision nephropathology, and present a vision for the near future.
Stone, J.J. Jr.; Bettis, E.S.; Mann, E.R.
1957-10-01
The electronic digital computer is designed to solve systems involving a plurality of simultaneous linear equations. The computer can solve a system which converges rather rapidly when using Von Seidel's method of approximation and performs the summations required for solving for the unknown terms by a method of successive approximations.
An improved data transfer and storage technique for hybrid computation
NASA Technical Reports Server (NTRS)
Hansing, A. M.
1972-01-01
Improved technique was developed for transferring and storing data at faster than real time speeds on hybrid computer. Predominant advantage is combined use of electronic relays, track and store units, and analog-to-digital and digital-to-analog conversion units of hybrid computer.
YF-12 cooperative airframe/propulsion control system program, volume 1
NASA Technical Reports Server (NTRS)
Anderson, D. L.; Connolly, G. F.; Mauro, F. M.; Reukauf, P. J.; Marks, R. (Editor)
1980-01-01
Several YF-12C airplane analog control systems were converted to a digital system. Included were the air data computer, autopilot, inlet control system, and autothrottle systems. This conversion was performed to allow assessment of digital technology applications to supersonic cruise aircraft. The digital system was composed of a digital computer and specialized interface unit. A large scale mathematical simulation of the airplane was used for integration testing and software checkout.
"I'm Good, but Not That Good": Digitally-Skilled Young People's Identity in Computing
ERIC Educational Resources Information Center
Wong, Billy
2017-01-01
Computers and information technology are fast becoming a part of young people's everyday life. However, there remains a difference between the majority who can use computers and the minority who are computer scientists or professionals. Drawing on 32 semi-structured interviews with digitally skilled young people (aged 13-19), we explore their…
Comprehensive Digital Imaging Network Project At Georgetown University Hospital
NASA Astrophysics Data System (ADS)
Mun, Seong K.; Stauffer, Douglas; Zeman, Robert; Benson, Harold; Wang, Paul; Allman, Robert
1987-10-01
The radiology practice is going through rapid changes due to the introduction of state-of-the-art computed based technologies. For the last twenty years we have witnessed the introduction of many new medical diagnostic imaging systems such as x-ray computed tomo-graphy, digital subtraction angiography (DSA), computerized nuclear medicine, single pho-ton emission computed tomography (SPECT), positron emission tomography (PET) and more re-cently, computerized digital radiography and nuclear magnetic resonance imaging (MRI). Other than the imaging systems, there has been a steady introduction of computed based information systems for radiology departments and hospitals.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-22
... Computer Software and Complex Electronics Used in Safety Systems of Nuclear Power Plants AGENCY: Nuclear...-1209, ``Software Requirement Specifications for Digital Computer Software and Complex Electronics used... Electronics Engineers (ANSI/IEEE) Standard 830-1998, ``IEEE Recommended Practice for Software Requirements...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hopwood, J.E.; Affeldt, B.
An IBM personal computer (PC), a Gerber coordinate digitizer, and a collection of other instruments make up a system known as the Coordinate Digitizer Interactive Processor (CDIP). The PC extracts coordinate data from the digitizer through a special interface, and then, after reformatting, transmits the data to a remote VAX computer, a floppy disk, and a display terminal. This system has improved the efficiency of producing printed circuit-board artwork and extended the useful life of the Gerber GCD-1 Digitizer. 1 ref., 12 figs.
A Digital Divide? Class and Gender in the Computer Practices of Two Mexicano Families.
ERIC Educational Resources Information Center
Menard-Warwick, Julia; Dabach, Dafney Blanca
The purpose of this paper is to critically re-examine the popular concept of a developing "digital divide." Based on qualitative studies of the computer practices of two Mexicano families resident in California, the paper argues with Warschauer (2001) that the "digital divide" should be seen as a continuum of varying degrees of…
Simulated Laboratory in Digital Logic.
ERIC Educational Resources Information Center
Cleaver, Thomas G.
Design of computer circuits used to be a pencil and paper task followed by laboratory tests, but logic circuit design can now be done in half the time as the engineer accesses a program which simulates the behavior of real digital circuits, and does all the wiring and testing on his computer screen. A simulated laboratory in digital logic has been…
SCANIT: centralized digitizing of forest resource maps or photographs
Elliot L. Amidon; E. Joyce Dye
1981-01-01
Spatial data on wildland resource maps and aerial photographs can be analyzed by computer after digitizing. SCANIT is a computerized system for encoding such data in digital form. The system, consisting of a collection of computer programs and subroutines, provides a powerful and versatile tool for a variety of resource analyses. SCANIT also may be converted easily to...
NASA Astrophysics Data System (ADS)
Saxena, Nishank; Hofmann, Ronny; Alpak, Faruk O.; Berg, Steffen; Dietderich, Jesse; Agarwal, Umang; Tandon, Kunj; Hunter, Sander; Freeman, Justin; Wilson, Ove Bjorn
2017-11-01
We generate a novel reference dataset to quantify the impact of numerical solvers, boundary conditions, and simulation platforms. We consider a variety of microstructures ranging from idealized pipes to digital rocks. Pore throats of the digital rocks considered are large enough to be well resolved with state-of-the-art micro-computerized tomography technology. Permeability is computed using multiple numerical engines, 12 in total, including, Lattice-Boltzmann, computational fluid dynamics, voxel based, fast semi-analytical, and known empirical models. Thus, we provide a measure of uncertainty associated with flow computations of digital media. Moreover, the reference and standards dataset generated is the first of its kind and can be used to test and improve new fluid flow algorithms. We find that there is an overall good agreement between solvers for idealized cross-section shape pipes. As expected, the disagreement increases with increase in complexity of the pore space. Numerical solutions for pipes with sinusoidal variation of cross section show larger variability compared to pipes of constant cross-section shapes. We notice relatively larger variability in computed permeability of digital rocks with coefficient of variation (of up to 25%) in computed values between various solvers. Still, these differences are small given other subsurface uncertainties. The observed differences between solvers can be attributed to several causes including, differences in boundary conditions, numerical convergence criteria, and parameterization of fundamental physics equations. Solvers that perform additional meshing of irregular pore shapes require an additional step in practical workflows which involves skill and can introduce further uncertainty. Computation times for digital rocks vary from minutes to several days depending on the algorithm and available computational resources. We find that more stringent convergence criteria can improve solver accuracy but at the expense of longer computation time.
Enhancing Tele-robotics with Immersive Virtual Reality
2017-11-03
graduate and undergraduate students within the Digital Gaming and Simulation, Computer Science, and psychology programs have actively collaborated...investigates the use of artificial intelligence and visual computing. Numerous fields across the human-computer interaction and gaming research areas...invested in digital gaming and simulation to cognitively stimulate humans by computers, forming a $10.5B industry [1]. On the other hand, cognitive
Digital Maps, Matrices and Computer Algebra
ERIC Educational Resources Information Center
Knight, D. G.
2005-01-01
The way in which computer algebra systems, such as Maple, have made the study of complex problems accessible to undergraduate mathematicians with modest computational skills is illustrated by some large matrix calculations, which arise from representing the Earth's surface by digital elevation models. Such problems are often considered to lie in…
Promoting Gender Equality in Digital Literacy
ERIC Educational Resources Information Center
Ertl, Bernhard; Helling, Kathrin
2011-01-01
This article deals with gender phenomena in the context of digital literacy. Studies show that computer use, computer skills, and computer-related self-concepts are subject to gender differences. These differences may affect classroom interactions as well as learning processes and have therefore to be considered carefully by teachers who apply…
Digital Data Transmission Via CATV.
ERIC Educational Resources Information Center
Stifle, Jack; And Others
A low cost communications network has been designed for use in the PLATO IV computer-assisted instruction system. Over 1,000 remote computer graphic terminals each requiring a 1200 bps channel are to be connected to one centrally located computer. Digital data are distributed to these terminals using standard commercial cable television (CATV)…
ERIC Educational Resources Information Center
Sargent, John
The Office of Technology Policy analyzed Bureau of Labor Statistics' growth projections for the core occupational classifications of IT (information technology) workers to assess future demand in the United States. Classifications studied were computer engineers, systems analysts, computer programmers, database administrators, computer support…
Sarpeshkar, R
2014-03-28
We analyse the pros and cons of analog versus digital computation in living cells. Our analysis is based on fundamental laws of noise in gene and protein expression, which set limits on the energy, time, space, molecular count and part-count resources needed to compute at a given level of precision. We conclude that analog computation is significantly more efficient in its use of resources than deterministic digital computation even at relatively high levels of precision in the cell. Based on this analysis, we conclude that synthetic biology must use analog, collective analog, probabilistic and hybrid analog-digital computational approaches; otherwise, even relatively simple synthetic computations in cells such as addition will exceed energy and molecular-count budgets. We present schematics for efficiently representing analog DNA-protein computation in cells. Analog electronic flow in subthreshold transistors and analog molecular flux in chemical reactions obey Boltzmann exponential laws of thermodynamics and are described by astoundingly similar logarithmic electrochemical potentials. Therefore, cytomorphic circuits can help to map circuit designs between electronic and biochemical domains. We review recent work that uses positive-feedback linearization circuits to architect wide-dynamic-range logarithmic analog computation in Escherichia coli using three transcription factors, nearly two orders of magnitude more efficient in parts than prior digital implementations.
Sarpeshkar, R.
2014-01-01
We analyse the pros and cons of analog versus digital computation in living cells. Our analysis is based on fundamental laws of noise in gene and protein expression, which set limits on the energy, time, space, molecular count and part-count resources needed to compute at a given level of precision. We conclude that analog computation is significantly more efficient in its use of resources than deterministic digital computation even at relatively high levels of precision in the cell. Based on this analysis, we conclude that synthetic biology must use analog, collective analog, probabilistic and hybrid analog–digital computational approaches; otherwise, even relatively simple synthetic computations in cells such as addition will exceed energy and molecular-count budgets. We present schematics for efficiently representing analog DNA–protein computation in cells. Analog electronic flow in subthreshold transistors and analog molecular flux in chemical reactions obey Boltzmann exponential laws of thermodynamics and are described by astoundingly similar logarithmic electrochemical potentials. Therefore, cytomorphic circuits can help to map circuit designs between electronic and biochemical domains. We review recent work that uses positive-feedback linearization circuits to architect wide-dynamic-range logarithmic analog computation in Escherichia coli using three transcription factors, nearly two orders of magnitude more efficient in parts than prior digital implementations. PMID:24567476
NASA Astrophysics Data System (ADS)
Cataldo, Franca
The world is at the dawn of a third industrial revolution, the digital revolution, that brings great changes the world over. Today, computing devices, the Internet, and the World Wide Web are vital technology tools that affect every aspect of everyday life and success. While computing technologies offer enormous benefits, there are equally enormous safety and security risks that have been growing exponentially since they became widely available to the public in 1994. Cybercriminals are increasingly implementing sophisticated and serious hack attacks and breaches upon our nation's government, financial institutions, organizations, communities, and private citizens. There is a great need for computer scientists to carry America's innovation and economic growth forward and for cybersecurity professionals to keep our nation safe from criminal hacking. In this digital age, computer science and cybersecurity are essential foundational ingredients of technological innovation, economic growth, and cybersecurity that span all industries. Yet, America's K-12 education institutions are not teaching the computer science and cybersecurity skills required to produce a technologically-savvy 21st century workforce. Education is the key to preparing students to enter the workforce and, therefore, American K-12 STEM education must be reformed to accommodate the teachings required in the digital age. Keywords: Cybersecurity Education, Cybersecurity Education Initiatives, Computer Science Education, Computer Science Education Initiatives, 21 st Century K-12 STEM Education Reform, 21st Century Digital Literacies, High-Tech Innovative Problem-Solving Skills, 21st Century Digital Workforce, Standardized Testing, Foreign Language and Culture Studies, Utica College, Professor Chris Riddell.
Digital optical conversion module
Kotter, D.K.; Rankin, R.A.
1988-07-19
A digital optical conversion module used to convert an analog signal to a computer compatible digital signal including a voltage-to-frequency converter, frequency offset response circuitry, and an electrical-to-optical converter. Also used in conjunction with the digital optical conversion module is an optical link and an interface at the computer for converting the optical signal back to an electrical signal. Suitable for use in hostile environments having high levels of electromagnetic interference, the conversion module retains high resolution of the analog signal while eliminating the potential for errors due to noise and interference. The module can be used to link analog output scientific equipment such as an electrometer used with a mass spectrometer to a computer. 2 figs.
Digital optical conversion module
Kotter, Dale K.; Rankin, Richard A.
1991-02-26
A digital optical conversion module used to convert an analog signal to a computer compatible digital signal including a voltage-to-frequency converter, frequency offset response circuitry, and an electrical-to-optical converter. Also used in conjunction with the digital optical conversion module is an optical link and an interface at the computer for converting the optical signal back to an electrical signal. Suitable for use in hostile environments having high levels of electromagnetic interference, the conversion module retains high resolution of the analog signal while eliminating the potential for errors due to noise and interference. The module can be used to link analog output scientific equipment such as an electrometer used with a mass spectrometer to a computer.
Color engineering in the age of digital convergence
NASA Astrophysics Data System (ADS)
MacDonald, Lindsay W.
1998-09-01
Digital color imaging has developed over the past twenty years from specialized scientific applications into the mainstream of computing. In addition to the phenomenal growth of computer processing power and storage capacity, great advances have been made in the capabilities and cost-effectiveness of color imaging peripherals. The majority of imaging applications, including the graphic arts, video and film have made the transition from analogue to digital production methods. Digital convergence of computing, communications and television now heralds new possibilities for multimedia publishing and mobile lifestyles. Color engineering, the application of color science to the design of imaging products, is an emerging discipline that poses exciting challenges to the international color imaging community for training, research and standards.
Tree-Structured Digital Organisms Model
NASA Astrophysics Data System (ADS)
Suzuki, Teruhiko; Nobesawa, Shiho; Tahara, Ikuo
Tierra and Avida are well-known models of digital organisms. They describe a life process as a sequence of computation codes. A linear sequence model may not be the only way to describe a digital organism, though it is very simple for a computer-based model. Thus we propose a new digital organism model based on a tree structure, which is rather similar to the generic programming. With our model, a life process is a combination of various functions, as if life in the real world is. This implies that our model can easily describe the hierarchical structure of life, and it can simulate evolutionary computation through mutual interaction of functions. We verified our model by simulations that our model can be regarded as a digital organism model according to its definitions. Our model even succeeded in creating species such as viruses and parasites.
Digital computer processing of peach orchard multispectral aerial photography
NASA Technical Reports Server (NTRS)
Atkinson, R. J.
1976-01-01
Several methods of analysis using digital computers applicable to digitized multispectral aerial photography, are described, with particular application to peach orchard test sites. This effort was stimulated by the recent premature death of peach trees in the Southeastern United States. The techniques discussed are: (1) correction of intensity variations by digital filtering, (2) automatic detection and enumeration of trees in five size categories, (3) determination of unhealthy foliage by infrared reflectances, and (4) four band multispectral classification into healthy and declining categories.
Pilot Study of Bovine Interdigital Cassetteless Computed Radiography
EL-SHAFAEY, El-Sayed Ahmed Awad; AOKI, Takahiro; ISHII, Mitsuo; YAMADA, Kazutaka
2013-01-01
ABSTRACT Twenty-one limbs of bovine cadavers (42 digits) were exposed to interdigital cassetteless imaging plate using computed radiography. The radiographic findings included exostosis, a rough planta surface, osteolysis of the apex of the distal phalanx and widening of the laminar zone between the distal phalanx and the hoof wall. All these findings were confirmed by computed tomography. The hindlimbs (19 digits) showed more changes than the forelimbs (10 digits), particularly in the lateral distal phalanx. The cassetteless computed radiography technique is expected to be an easily applicable method for the distal phalanx rather than a conventional cassette-plate and/or the film-screen cassetteless methods. PMID:23782542
A 21st Century Science, Technology, and Innovation Strategy for Americas National Security
2016-05-01
areas. Advanced Computing and Communications The exponential growth of the digital economy, driven by ubiquitous computing and communication...weapons- focused R&D, many of the capabilities being developed have significant dual-use potential. Digital connectivity, for instance, brings...scale than traditional recombinant DNA techniques, and to share these designs digitally . Nanotechnology promises the ability to engineer entirely
ERIC Educational Resources Information Center
Watkins, Ryan; Engel, Laura C.; Hastedt, Dirk
2015-01-01
The rise of digital information and communication technologies (ICT) has made the acquisition of computer and information literacy (CIL) a leading factor in creating an engaged, informed, and employable citizenry. However, are young people, often described as "digital natives" or the "net generation," developing the necessary…
US GeoData: Digital cartographic and geographic data
,
1985-01-01
The increasing use of computers for storing and analyzing earth science information has sparked a growth in the demand for various types of cartographic data in digital form. The production of map data in computerized form is called digital cartography, and it involves the collection, storage, processing, analysis, and display of map data with the aid of computers. The U.S. Geological Survey, the Nation's largest earth science research agency, has expanded its national mapping program to incorporate operations associated with digital cartography, including the collection of planimetric, elevation, and geographic names information in digital form. This digital information is available for use in meeting the multipurpose needs and applications of the map user community.
Plans for wind energy system simulation
NASA Technical Reports Server (NTRS)
Dreier, M. E.
1978-01-01
A digital computer code and a special purpose hybrid computer, were introduced. The digital computer program, the Root Perturbation Method or RPM, is an implementation of the classic floquet procedure which circumvents numerical problems associated with the extraction of Floquet roots. The hybrid computer, the Wind Energy System Time domain simulator (WEST), yields real time loads and deformation information essential to design and system stability investigations.
NASA Astrophysics Data System (ADS)
Cook, Perry
This chapter covers algorithms, technologies, computer languages, and systems for computer music. Computer music involves the application of computers and other digital/electronic technologies to music composition, performance, theory, history, and perception. The field combines digital signal processing, computational algorithms, computer languages, hardware and software systems, acoustics, psychoacoustics (low-level perception of sounds from the raw acoustic signal), and music cognition (higher-level perception of musical style, form, emotion, etc.). Although most people would think that analog synthesizers and electronic music substantially predate the use of computers in music, many experiments and complete computer music systems were being constructed and used as early as the 1950s.
On the Need for Research Evidence to Guide the Design of Computer Games for Learning
ERIC Educational Resources Information Center
Mayer, Richard E.
2015-01-01
Computer games for learning (also called video games or digital games) have potential to improve education. This is the intriguing idea that motivates this special issue of the "Educational Psychologist" on "Psychological Perspectives on Digital Games and Learning." Computer games for learning are games delivered via computer…
A Method for Identifying Contours in Processing Digital Images from Computer Tomograph
NASA Astrophysics Data System (ADS)
Roşu, Şerban; Pater, Flavius; Costea, Dan; Munteanu, Mihnea; Roşu, Doina; Fratila, Mihaela
2011-09-01
The first step in digital processing of two-dimensional computed tomography images is to identify the contour of component elements. This paper deals with the collective work of specialists in medicine and applied mathematics in computer science on elaborating new algorithms and methods in medical 2D and 3D imagery.
Mental Computation or Standard Algorithm? Children's Strategy Choices on Multi-Digit Subtractions
ERIC Educational Resources Information Center
Torbeyns, Joke; Verschaffel, Lieven
2016-01-01
This study analyzed children's use of mental computation strategies and the standard algorithm on multi-digit subtractions. Fifty-eight Flemish 4th graders of varying mathematical achievement level were individually offered subtractions that either stimulated the use of mental computation strategies or the standard algorithm in one choice and two…
Proceedings of the Fourth Annual Workshop on the Use of Digital Computers in Process Control.
ERIC Educational Resources Information Center
Smith, Cecil L., Ed.
Contents: Computer hardware testing (results of vendor-user interaction); CODIL (a new language for process control programing); the design and implementation of control systems utilizing CRT display consoles; the systems contractor - valuable professional or unnecessary middle man; power station digital computer applications; from inspiration to…
A Digital Computer Simulation of Cardiovascular and Renal Physiology.
ERIC Educational Resources Information Center
Tidball, Charles S.
1979-01-01
Presents the physiological MACPEE, one of a family of digital computer simulations used in Canada and Great Britain. A general description of the model is provided, along with a sample of computer output format, options for making interventions, advanced capabilities, an evaluation, and technical information for running a MAC model. (MA)
Removing the center from computing: biology's new mode of digital knowledge production.
November, Joseph
2011-06-01
This article shows how the USA's National Institutes of Health (NIH) helped to bring about a major shift in the way computers are used to produce knowledge and in the design of computers themselves as a consequence of its early 1960s efforts to introduce information technology to biologists. Starting in 1960 the NIH sought to reform the life sciences by encouraging researchers to make use of digital electronic computers, but despite generous federal support biologists generally did not embrace the new technology. Initially the blame fell on biologists' lack of appropriate (i.e. digital) data for computers to process. However, when the NIH consulted MIT computer architect Wesley Clark about this problem, he argued that the computer's quality as a device that was centralized posed an even greater challenge to potential biologist users than did the computer's need for digital data. Clark convinced the NIH that if the agency hoped to effectively computerize biology, it would need to satisfy biologists' experimental and institutional needs by providing them the means to use a computer without going to a computing center. With NIH support, Clark developed the 1963 Laboratory Instrument Computer (LINC), a small, real-time interactive computer intended to be used inside the laboratory and controlled entirely by its biologist users. Once built, the LINC provided a viable alternative to the 1960s norm of large computers housed in computing centers. As such, the LINC not only became popular among biologists, but also served in later decades as an important precursor of today's computing norm in the sciences and far beyond, the personal computer.
NASA Astrophysics Data System (ADS)
Xiong, Ting; He, Zhiwen
2017-06-01
Cloud computing was first proposed by Google Company in the United States, which was based on the Internet center, providing a standard and open network sharing service approach. With the rapid development of the higher education in China, the educational resources provided by colleges and universities had greatly gap in the actual needs of teaching resources. therefore, Cloud computing of using the Internet technology to provide shared methods liked the timely rain, which had become an important means of the Digital Education on sharing applications in the current higher education. Based on Cloud computing environment, the paper analyzed the existing problems about the sharing of digital educational resources in Jiangxi Province Independent Colleges. According to the sharing characteristics of mass storage, efficient operation and low input about Cloud computing, the author explored and studied the design of the sharing model about the digital educational resources of higher education in Independent College. Finally, the design of the shared model was put into the practical applications.
Digital model as an alternative to plaster model in assessment of space analysis
Kumar, A. Anand; Phillip, Abraham; Kumar, Sathesh; Rawat, Anuradha; Priya, Sakthi; Kumaran, V.
2015-01-01
Introduction: Digital three-dimensional models are widely used for orthodontic diagnosis. The purpose of this study was to appraise the accuracy of digital models obtained from computer-aided design/computer-aided manufacturing (CAD/CAM) and cone-beam computed tomography (CBCT) for tooth-width measurements and the Bolton analysis. Materials and Methods: Digital models (CAD/CAM, CBCT) and plaster model were made for each of 50 subjects. Tooth-width measurements on the digital models (CAD/CAM, CBCT) were compared with those on the corresponding plaster models. The anterior and overall Bolton ratios were calculated for each participant and for each method. The paired t-test was applied to determine the validity. Results: Tooth-width measurements, anterior, and overall Bolton ratio of digital models of CAD/CAM and CBCT did not differ significantly from those on the plaster models. Conclusion: Hence, both CBCT and CAD/CAM are trustable and promising technique that can replace plaster models due to its overwhelming advantages. PMID:26538899
NASA Astrophysics Data System (ADS)
Zacharovas, Stanislovas; Nikolskij, Andrej; Kuchin, Jevgenij
2011-02-01
We have created a programming tool which uses image data provided by webcam connected to personal computer and gives user an ability to see the future digital hologram preview on his computer screen, before sending video data to holographic printing companies. In order to print digital hologram, one needs to have a sequence of images of the same scene taken from different angles and nowadays web cameras - stand-alone or incorporated into mobile computer, can be an acceptable source of such image sequences. In this article we are describing this DIY holographic imaging process in details.
Near real-time digital holographic microscope based on GPU parallel computing
NASA Astrophysics Data System (ADS)
Zhu, Gang; Zhao, Zhixiong; Wang, Huarui; Yang, Yan
2018-01-01
A transmission near real-time digital holographic microscope with in-line and off-axis light path is presented, in which the parallel computing technology based on compute unified device architecture (CUDA) and digital holographic microscopy are combined. Compared to other holographic microscopes, which have to implement reconstruction in multiple focal planes and are time-consuming the reconstruction speed of the near real-time digital holographic microscope can be greatly improved with the parallel computing technology based on CUDA, so it is especially suitable for measurements of particle field in micrometer and nanometer scale. Simulations and experiments show that the proposed transmission digital holographic microscope can accurately measure and display the velocity of particle field in micrometer scale, and the average velocity error is lower than 10%.With the graphic processing units(GPU), the computing time of the 100 reconstruction planes(512×512 grids) is lower than 120ms, while it is 4.9s using traditional reconstruction method by CPU. The reconstruction speed has been raised by 40 times. In other words, it can handle holograms at 8.3 frames per second and the near real-time measurement and display of particle velocity field are realized. The real-time three-dimensional reconstruction of particle velocity field is expected to achieve by further optimization of software and hardware. Keywords: digital holographic microscope,
NASA Astrophysics Data System (ADS)
Ceres, M.; Heselton, L. R., III
1981-11-01
This manual describes the computer programs for the FIREFINDER Digital Topographic Data Verification-Library-Dubbing System (FFDTDVLDS), and will assist in the maintenance of these programs. The manual contains detailed flow diagrams and associated descriptions for each computer program routine and subroutine. Complete computer program listings are also included. This information should be used when changes are made in the computer programs. The operating system has been designed to minimize operator intervention.
Modified-Signed-Digit Optical Computing Using Fan-Out
NASA Technical Reports Server (NTRS)
Liu, Hua-Kuang; Zhou, Shaomin; Yeh, Pochi
1996-01-01
Experimental optical computing system containing optical fan-out elements implements modified signed-digit (MSD) arithmetic and logic. In comparison with previous optical implementations of MSD arithmetic, this one characterized by larger throughput, greater flexibility, and simpler optics.
Precision digital control systems
NASA Astrophysics Data System (ADS)
Vyskub, V. G.; Rozov, B. S.; Savelev, V. I.
This book is concerned with the characteristics of digital control systems of great accuracy. A classification of such systems is considered along with aspects of stabilization, programmable control applications, digital tracking systems and servomechanisms, and precision systems for the control of a scanning laser beam. Other topics explored are related to systems of proportional control, linear devices and methods for increasing precision, approaches for further decreasing the response time in the case of high-speed operation, possibilities for the implementation of a logical control law, and methods for the study of precision digital control systems. A description is presented of precision automatic control systems which make use of electronic computers, taking into account the existing possibilities for an employment of computers in automatic control systems, approaches and studies required for including a computer in such control systems, and an analysis of the structure of automatic control systems with computers. Attention is also given to functional blocks in the considered systems.
NASA Technical Reports Server (NTRS)
Shiva, S. G.
1978-01-01
Several high level languages which evolved over the past few years for describing and simulating the structure and behavior of digital systems, on digital computers are assessed. The characteristics of the four prominent languages (CDL, DDL, AHPL, ISP) are summarized. A criterion for selecting a suitable hardware description language for use in an automatic integrated circuit design environment is provided.
Trend Alert: A History Teacher's Guide to Using Podcasts in the Classroom
ERIC Educational Resources Information Center
Swan, Kathleen Owings; Hofer, Mark
2009-01-01
A "podcast" (an amalgam of the word broadcast and the iPod digital audio player) is essentially a broadcast of digital audio files on the web that users can listen to on their computer or digital audio player (e.g., iPod). Podcasts can be automatically delivered to an iPod or computer whenever new content is available. This unique feature of…
Histopathological Image Analysis: A Review
Gurcan, Metin N.; Boucheron, Laura; Can, Ali; Madabhushi, Anant; Rajpoot, Nasir; Yener, Bulent
2010-01-01
Over the past decade, dramatic increases in computational power and improvement in image analysis algorithms have allowed the development of powerful computer-assisted analytical approaches to radiological data. With the recent advent of whole slide digital scanners, tissue histopathology slides can now be digitized and stored in digital image form. Consequently, digitized tissue histopathology has now become amenable to the application of computerized image analysis and machine learning techniques. Analogous to the role of computer-assisted diagnosis (CAD) algorithms in medical imaging to complement the opinion of a radiologist, CAD algorithms have begun to be developed for disease detection, diagnosis, and prognosis prediction to complement to the opinion of the pathologist. In this paper, we review the recent state of the art CAD technology for digitized histopathology. This paper also briefly describes the development and application of novel image analysis technology for a few specific histopathology related problems being pursued in the United States and Europe. PMID:20671804
Tapie, L; Lebon, N; Mawussi, B; Fron Chabouis, H; Duret, F; Attal, J-P
2015-01-01
As digital technology infiltrates every area of daily life, including the field of medicine, so it is increasingly being introduced into dental practice. Apart from chairside practice, computer-aided design/computer-aided manufacturing (CAD/CAM) solutions are available for creating inlays, crowns, fixed partial dentures (FPDs), implant abutments, and other dental prostheses. CAD/CAM dental solutions can be considered a chain of digital devices and software for the almost automatic design and creation of dental restorations. However, dentists who want to use the technology often do not have the time or knowledge to understand it. A basic knowledge of the CAD/CAM digital workflow for dental restorations can help dentists to grasp the technology and purchase a CAM/CAM system that meets the needs of their office. This article provides a computer-science and mechanical-engineering approach to the CAD/CAM digital workflow to help dentists understand the technology.
A Medical Image Backup Architecture Based on a NoSQL Database and Cloud Computing Services.
Santos Simões de Almeida, Luan Henrique; Costa Oliveira, Marcelo
2015-01-01
The use of digital systems for storing medical images generates a huge volume of data. Digital images are commonly stored and managed on a Picture Archiving and Communication System (PACS), under the DICOM standard. However, PACS is limited because it is strongly dependent on the server's physical space. Alternatively, Cloud Computing arises as an extensive, low cost, and reconfigurable resource. However, medical images contain patient information that can not be made available in a public cloud. Therefore, a mechanism to anonymize these images is needed. This poster presents a solution for this issue by taking digital images from PACS, converting the information contained in each image file to a NoSQL database, and using cloud computing to store digital images.
Automated attendance accounting system
NASA Technical Reports Server (NTRS)
Chapman, C. P. (Inventor)
1973-01-01
An automated accounting system useful for applying data to a computer from any or all of a multiplicity of data terminals is disclosed. The system essentially includes a preselected number of data terminals which are each adapted to convert data words of decimal form to another form, i.e., binary, usable with the computer. Each data terminal may take the form of a keyboard unit having a number of depressable buttons or switches corresponding to selected data digits and/or function digits. A bank of data buffers, one of which is associated with each data terminal, is provided as a temporary storage. Data from the terminals is applied to the data buffers on a digit by digit basis for transfer via a multiplexer to the computer.
Characterization of a 16-Bit Digitizer for Lidar Data Acquisition
NASA Technical Reports Server (NTRS)
Williamson, Cynthia K.; DeYoung, Russell J.
2000-01-01
A 6-MHz 16-bit waveform digitizer was evaluated for use in atmospheric differential absorption lidar (DIAL) measurements of ozone. The digitizer noise characteristics were evaluated, and actual ozone DIAL atmospheric returns were digitized. This digitizer could replace computer-automated measurement and control (CAMAC)-based commercial digitizers and improve voltage accuracy.
Status of emerging standards for removable computer storage media and related contributions of NIST
NASA Technical Reports Server (NTRS)
Podio, Fernando L.
1992-01-01
Standards for removable computer storage media are needed so that users may reliably interchange data both within and among various computer installations. Furthermore, media interchange standards support competition in industry and prevent sole-source lock-in. NIST participates in magnetic tape and optical disk standards development through Technical Committees X3B5, Digital Magnetic Tapes, X3B11, Optical Digital Data Disk, and the Joint Technical Commission on Data Permanence. NIST also participates in other relevant national and international standards committees for removable computer storage media. Industry standards for digital magnetic tapes require the use of Standard Reference Materials (SRM's) developed and maintained by NIST. In addition, NIST has been studying care and handling procedures required for digital magnetic tapes. NIST has developed a methodology for determining the life expectancy of optical disks. NIST is developing care and handling procedures for optical digital data disks and is involved in a program to investigate error reporting capabilities of optical disk drives. This presentation reflects the status of emerging magnetic tape and optical disk standards, as well as NIST's contributions in support of these standards.
Mendonca, Derick A; Naidoo, Sybill D; Skolnick, Gary; Skladman, Rachel; Woo, Albert S
2013-07-01
Craniofacial anthropometry by direct caliper measurements is a common method of quantifying the morphology of the cranial vault. New digital imaging modalities including computed tomography and three-dimensional photogrammetry are similarly being used to obtain craniofacial surface measurements. This study sought to compare the accuracy of anthropometric measurements obtained by calipers versus 2 methods of digital imaging.Standard anterior-posterior, biparietal, and cranial index measurements were directly obtained on 19 participants with an age range of 1 to 20 months. Computed tomographic scans and three-dimensional photographs were both obtained on each child within 2 weeks of the clinical examination. Two analysts measured the anterior-posterior and biparietal distances on the digital images. Measures of reliability and bias between the modalities were calculated and compared.Caliper measurements were found to underestimate the anterior-posterior and biparietal distances as compared with those of the computed tomography and the three-dimensional photogrammetry (P < 0.001). Cranial index measurements between the computed tomography and the calipers differed by up to 6%. The difference between the 2 modalities was statistically significant (P = 0.021). The biparietal and cranial index results were similar between the digital modalities, but the anterior-posterior measurement was greater with the three-dimensional photogrammetry (P = 0.002). The coefficients of variation for repeated measures based on the computed tomography and the three-dimensional photogrammetry were 0.008 and 0.007, respectively.In conclusion, measurements based on digital modalities are generally reliable and interchangeable. Caliper measurements lead to underestimation of anterior-posterior and biparietal values compared with digital imaging.
ERIC Educational Resources Information Center
Kim, SugHee; Chung, KwangSik; Yu, HeonChang
2013-01-01
The purpose of this paper is to propose a training program for creative problem solving based on computer programming. The proposed program will encourage students to solve real-life problems through a creative thinking spiral related to cognitive skills with computer programming. With the goal of enhancing digital fluency through this proposed…
Developing Digital Immigrants' Computer Literacy: The Case of Unemployed Women
ERIC Educational Resources Information Center
Ktoridou, Despo; Eteokleous-Grigoriou, Nikleia
2011-01-01
Purpose: The purpose of this study is to evaluate the effectiveness of a 40-hour computer course for beginners provided to a group of unemployed women learners with no/minimum computer literacy skills who can be characterized as digital immigrants. The aim of the study is to identify participants' perceptions and experiences regarding technology,…
Applications in Data-Intensive Computing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shah, Anuj R.; Adkins, Joshua N.; Baxter, Douglas J.
2010-04-01
This book chapter, to be published in Advances in Computers, Volume 78, in 2010 describes applications of data intensive computing (DIC). This is an invited chapter resulting from a previous publication on DIC. This work summarizes efforts coming out of the PNNL's Data Intensive Computing Initiative. Advances in technology have empowered individuals with the ability to generate digital content with mouse clicks and voice commands. Digital pictures, emails, text messages, home videos, audio, and webpages are common examples of digital content that are generated on a regular basis. Data intensive computing facilitates human understanding of complex problems. Data-intensive applications providemore » timely and meaningful analytical results in response to exponentially growing data complexity and associated analysis requirements through the development of new classes of software, algorithms, and hardware.« less
Generalized dynamic engine simulation techniques for the digital computer
NASA Technical Reports Server (NTRS)
Sellers, J.; Teren, F.
1974-01-01
Recently advanced simulation techniques have been developed for the digital computer and used as the basis for development of a generalized dynamic engine simulation computer program, called DYNGEN. This computer program can analyze the steady state and dynamic performance of many kinds of aircraft gas turbine engines. Without changes to the basic program, DYNGEN can analyze one- or two-spool turbofan engines. The user must supply appropriate component performance maps and design-point information. Examples are presented to illustrate the capabilities of DYNGEN in the steady state and dynamic modes of operation. The analytical techniques used in DYNGEN are briefly discussed, and its accuracy is compared with a comparable simulation using the hybrid computer. The impact of DYNGEN and similar all-digital programs on future engine simulation philosophy is also discussed.
Generalized dynamic engine simulation techniques for the digital computer
NASA Technical Reports Server (NTRS)
Sellers, J.; Teren, F.
1974-01-01
Recently advanced simulation techniques have been developed for the digital computer and used as the basis for development of a generalized dynamic engine simulation computer program, called DYNGEN. This computer program can analyze the steady state and dynamic performance of many kinds of aircraft gas turbine engines. Without changes to the basic program DYNGEN can analyze one- or two-spool turbofan engines. The user must supply appropriate component performance maps and design-point information. Examples are presented to illustrate the capabilities of DYNGEN in the steady state and dynamic modes of operation. The analytical techniques used in DYNGEN are briefly discussed, and its accuracy is compared with a comparable simulation using the hybrid computer. The impact of DYNGEN and similar all-digital programs on future engine simulation philosophy is also discussed.
Generalized dynamic engine simulation techniques for the digital computers
NASA Technical Reports Server (NTRS)
Sellers, J.; Teren, F.
1975-01-01
Recently advanced simulation techniques have been developed for the digital computer and used as the basis for development of a generalized dynamic engine simulation computer program, called DYNGEN. This computer program can analyze the steady state and dynamic performance of many kinds of aircraft gas turbine engines. Without changes to the basic program, DYNGEN can analyze one- or two-spool turbofan engines. The user must supply appropriate component performance maps and design point information. Examples are presented to illustrate the capabilities of DYNGEN in the steady state and dynamic modes of operation. The analytical techniques used in DYNGEN are briefly discussed, and its accuracy is compared with a comparable simulation using the hybrid computer. The impact of DYNGEN and similar digital programs on future engine simulation philosophy is also discussed.
NASA Technical Reports Server (NTRS)
Peri, Frank, Jr.
1992-01-01
A flight digital data acquisition system that uses the MIL-STD-1553B bus for transmission of data to a host computer for control law processing is described. The instrument, the Remote Interface Unit (RIU), can accommodate up to 16 input channels and eight output channels. The RIU employs a digital signal processor to perform local digital filtering before sending data to the host. The system allows flexible sensor and actuator data organization to facilitate quick control law computations on the host computer. The instrument can also run simple control laws autonomously without host intervention. The RIU and host computer together have replaced a similar larger, ground minicomputer system with favorable results.
NASA Technical Reports Server (NTRS)
Nagle, H. T., Jr.
1972-01-01
A three part survey is made of the state-of-the-art in digital filtering. Part one presents background material including sampled data transformations and the discrete Fourier transform. Part two, digital filter theory, gives an in-depth coverage of filter categories, transfer function synthesis, quantization and other nonlinear errors, filter structures and computer aided design. Part three presents hardware mechanization techniques. Implementations by general purpose, mini-, and special-purpose computers are presented.
NASA Technical Reports Server (NTRS)
Bailey, David H.; Borwein, Jonathan M.; Borwein, Peter B.; Plouffe, Simon
1996-01-01
This article gives a brief history of the analysis and computation of the mathematical constant Pi=3.14159 ..., including a number of the formulas that have been used to compute Pi through the ages. Recent developments in this area are then discussed in some detail, including the recent computation of Pi to over six billion decimal digits using high-order convergent algorithms, and a newly discovered scheme that permits arbitrary individual hexadecimal digits of Pi to be computed.
The potential of multi-port optical memories in digital computing
NASA Technical Reports Server (NTRS)
Alford, C. O.; Gaylord, T. K.
1975-01-01
A high-capacity memory with a relatively high data transfer rate and multi-port simultaneous access capability may serve as the basis for new computer architectures. The implementation of a multi-port optical memory is discussed. Several computer structures are presented that might profitably use such a memory. These structures include (1) a simultaneous record access system, (2) a simultaneously shared memory computer system, and (3) a parallel digital processing structure.
Digital Ethics: Computers, Photographs, and the Manipulation of Pixels.
ERIC Educational Resources Information Center
Mercedes, Dawn
1996-01-01
Summarizes negative aspects of computer technology and problems inherent in the field of digital imaging. Considers the postmodernist response that borrowing and alteration are essential characteristics of the technology. Discusses the implications of this for education and research. (MJP)
Jargon that Computes: Today's PC Terminology.
ERIC Educational Resources Information Center
Crawford, Walt
1997-01-01
Discusses PC (personal computer) and telecommunications terminology in context: Integrated Services Digital Network (ISDN); Asymmetric Digital Subscriber Line (ADSL); cable modems; satellite downloads; T1 and T3 lines; magnitudes ("giga-,""nano-"); Central Processing Unit (CPU); Random Access Memory (RAM); Universal Serial Bus…
Digital Storytelling as an Interactive Digital Media Context
ERIC Educational Resources Information Center
Anderson, Kate T.; Chua, Puay Hoe
2010-01-01
Digital storytelling involves the creation of short, personal narratives combining images, sounds, and text in a multimedia computer-based platform. In education, digital storytelling has been used to foster learning in formal and informal spaces worldwide. The authors offer a critical discussion of claims about digital storytelling's usefulness…
ERIC Educational Resources Information Center
Prensky, Marc
2006-01-01
"Digital natives" refer to today's students because they are native speakers of technology, fluent in the digital language of computers, video games, and the Internet. Those who were not born into the digital world are referred to as digital immigrants. Educators, considered digital immigrants, have slid into the 21st century--and into the digital…
Cellular automaton supercomputing
NASA Technical Reports Server (NTRS)
Wolfram, Stephen
1987-01-01
Many of the models now used in science and engineering are over a century old. And most of them can be implemented on modern digital computers only with considerable difficulty. Some new basic models are discussed which are much more directly suitable for digital computer simulation. The fundamental principle is that the models considered herein are as suitable as possible for implementation on digital computers. It is then a matter of scientific analysis to determine whether such models can reproduce the behavior seen in physical and other systems. Such analysis was carried out in several cases, and the results are very encouraging.
The research of laser marking control technology
NASA Astrophysics Data System (ADS)
Zhang, Qiue; Zhang, Rong
2009-08-01
In the area of Laser marking, the general control method is insert control card to computer's mother board, it can not support hot swap, it is difficult to assemble or it. Moreover, the one marking system must to equip one computer. In the system marking, the computer can not to do the other things except to transmit marking digital information. Otherwise it can affect marking precision. Based on traditional control methods existed some problems, introduced marking graphic editing and digital processing by the computer finish, high-speed digital signal processor (DSP) control marking the whole process. The laser marking controller is mainly contain DSP2812, digital memorizer, DAC (digital analog converting) transform unit circuit, USB interface control circuit, man-machine interface circuit, and other logic control circuit. Download the marking information which is processed by computer to U disk, DSP read the information by USB interface on time, then processing it, adopt the DSP inter timer control the marking time sequence, output the scanner control signal by D/A parts. Apply the technology can realize marking offline, thereby reduce the product cost, increase the product efficiency. The system have good effect in actual unit markings, the marking speed is more quickly than PCI control card to 20 percent. It has application value in practicality.
ERIC Educational Resources Information Center
Choudhury, Sayeed; Hobbs, Benjamin; Lorie, Mark; Flores, Nicholas; Coleman, Anita; Martin, Mairead; Kuhlman, David L.; McNair, John H.; Rhodes, William A.; Tipton, Ron; Agnew, Grace; Nicholson, Dennis; Macgregor, George
2002-01-01
Includes four articles that address issues related to digital libraries. Highlights include a framework for evaluating digital library services, particularly academic research libraries; interdisciplinary approaches to education about digital libraries that includes library and information science and computing; digital rights management; and the…
Seminar on Understanding Digital Control and Analysis in Vibration Test Systems
NASA Technical Reports Server (NTRS)
1975-01-01
The advantages of the digital methods over the analog vibration methods are demonstrated. The following topics are covered: (1) methods of computer-controlled random vibration and reverberation acoustic testing, (2) methods of computer-controlled sinewave vibration testing, and (3) methods of computer-controlled shock testing. General algorithms are described in the form of block diagrams and flow diagrams.
Reliability modeling of fault-tolerant computer based systems
NASA Technical Reports Server (NTRS)
Bavuso, Salvatore J.
1987-01-01
Digital fault-tolerant computer-based systems have become commonplace in military and commercial avionics. These systems hold the promise of increased availability, reliability, and maintainability over conventional analog-based systems through the application of replicated digital computers arranged in fault-tolerant configurations. Three tightly coupled factors of paramount importance, ultimately determining the viability of these systems, are reliability, safety, and profitability. Reliability, the major driver affects virtually every aspect of design, packaging, and field operations, and eventually produces profit for commercial applications or increased national security. However, the utilization of digital computer systems makes the task of producing credible reliability assessment a formidable one for the reliability engineer. The root of the problem lies in the digital computer's unique adaptability to changing requirements, computational power, and ability to test itself efficiently. Addressed here are the nuances of modeling the reliability of systems with large state sizes, in the Markov sense, which result from systems based on replicated redundant hardware and to discuss the modeling of factors which can reduce reliability without concomitant depletion of hardware. Advanced fault-handling models are described and methods of acquiring and measuring parameters for these models are delineated.
Computer Graphics Instruction in VizClass
ERIC Educational Resources Information Center
Grimes, Douglas; Warschauer, Mark; Hutchinson, Tara; Kuester, Falko
2005-01-01
"VizClass" is a university classroom environment designed to offer students in computer graphics and engineering courses up-to-date visualization technologies. Three digital whiteboards and a three-dimensional stereoscopic display provide complementary display surfaces. Input devices include touchscreens on the digital whiteboards, remote…
ERIC Educational Resources Information Center
Negroponto, Nicholas
1995-01-01
According to the author's book "Being Digital," our world is shifting from atoms to bits. Digitally rendered information, combined with personal computing power and networks, will make computers active participants in our everyday lives. "Teaching-disabled" classrooms will move from passivity to active participation and…
NASA Technical Reports Server (NTRS)
Patterson, G.
1973-01-01
The data processing procedures and the computer programs were developed to predict structural responses using the Impulse Transfer Function (ITF) method. There are three major steps in the process: (1) analog-to-digital (A-D) conversion of the test data to produce Phase I digital tapes (2) processing of the Phase I digital tapes to extract ITF's and storing them in a permanent data bank, and (3) predicting structural responses to a set of applied loads. The analog to digital conversion is performed by a standard package which will be described later in terms of the contents of the resulting Phase I digital tape. Two separate computer programs have been developed to perform the digital processing.
Lin, Wei-Shao; Metz, Michael J; Pollini, Adrien; Ntounis, Athanasios; Morton, Dean
2014-12-01
This dental technique report describes a digital workflow with digital data acquisition at the implant level, computer-aided design and computer-aided manufacturing fabricated, tissue-colored, anodized titanium framework, individually luted zirconium oxide restorations, and autopolymerizing injection-molded acrylic resin to fabricate an implant-supported, metal-ceramic-resin fixed complete dental prosthesis in an edentulous mandible. The 1-step computer-aided design and computer-aided manufacturing fabrication of titanium framework and zirconium oxide restorations can provide a cost-effective alternative to the conventional metal-resin fixed complete dental prosthesis. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Rasmusson, Maria; Åberg-Bengtsson, Lisbeth
2015-01-01
Data from a Swedish PISA-sample were used (1) to identify a digital reading factor, (2) to investigate gender differences in this factor (if found), and (3) to explore how computer game playing might relate to digital reading performance and gender. The analyses were conducted with structural equation modeling techniques. In addition to an overall…
User’s Manual for the Modular Analysis-Package Libraries ANAPAC and TRANL
1977-09-01
number) Computer software Fourier transforms Computer software library Interpolation software Digitized data...disregarded to give the user a simplified plot. (b) The last digit of ISPACE determines the type of line to be drawn, provided KODE is not...negative. If the last digit of ISPACE is 0 a solid line is drawn 1 a dashed line is drawn - - - 2 a dotted line is drawn .... 3 a dash-dot line is
Digital computer operation of a nuclear reactor
Colley, R.W.
1982-06-29
A method is described for the safe operation of a complex system such as a nuclear reactor using a digital computer. The computer is supplied with a data base containing a list of the safe state of the reactor and a list of operating instructions for achieving a safe state when the actual state of the reactor does not correspond to a listed safe state, the computer selects operating instructions to return the reactor to a safe state.
Digital computer operation of a nuclear reactor
Colley, Robert W.
1984-01-01
A method is described for the safe operation of a complex system such as a nuclear reactor using a digital computer. The computer is supplied with a data base containing a list of the safe state of the reactor and a list of operating instructions for achieving a safe state when the actual state of the reactor does not correspond to a listed safe state, the computer selects operating instructions to return the reactor to a safe state.
NCSTRL: Design and Deployment of a Globally Distributed Digital Library.
ERIC Educational Resources Information Center
Davies, James R.; Lagoze, Carl
2000-01-01
Discusses the development of a digital library architecture that allows the creation of digital libraries within the World Wide Web. Describes a digital library, NCSTRL (Networked Computer Science Technical Research Library), within which the work has taken place and explains Dienst, a protocol and architecture for distributed digital libraries.…
,
1990-01-01
The development of geographic information systems (GIS) is a rapidly growing industry that supports natural resources, studies, land management, environmental analysis, and urban and transporation planning. The increasing use of computers for storing and analyzing earth science information has greatly expanded the demand for digital cartographic and geographic data. Digital cartography involves the collection, storage, processing, analysis, and display of map data with the aid of computers. The U.S. Geological Survey (USGS), the Nation's largest earth science research agency, through its National Mapping Program, has expanded digital cartography operations to include the collection of elevation, planimetric, land use and land cover, and geographic names information in digital form. This digital information is available on 9-track magnetic tapes and, in the case of 1:2,000,000-scale planimetric digital line graph data, in Compact Disc Read Only Memory (CD-ROM) format. Digital information can be used with all types of geographic and land information systems.
Hardware synthesis from DDL. [Digital Design Language for computer aided design and test of LSI
NASA Technical Reports Server (NTRS)
Shah, A. M.; Shiva, S. G.
1981-01-01
The details of the digital systems can be conveniently input into the design automation system by means of Hardware Description Languages (HDL). The Computer Aided Design and Test (CADAT) system at NASA MSFC is used for the LSI design. The Digital Design Language (DDL) has been selected as HDL for the CADAT System. DDL translator output can be used for the hardware implementation of the digital design. This paper addresses problems of selecting the standard cells from the CADAT standard cell library to realize the logic implied by the DDL description of the system.
Digital Textbooks. Research Brief
ERIC Educational Resources Information Center
Johnston, Howard
2011-01-01
Despite their growing popularity, digital alternatives to conventional textbooks are stirring up controversy. With the introduction of tablet computers, and the growing trend toward "cloud computing" and "open source" software, the trend is accelerating because costs are coming down and free or inexpensive materials are becoming more available.…
Computer considerations for real time simulation of a generalized rotor model
NASA Technical Reports Server (NTRS)
Howe, R. M.; Fogarty, L. E.
1977-01-01
Scaled equations were developed to meet requirements for real time computer simulation of the rotor system research aircraft. These equations form the basis for consideration of both digital and hybrid mechanization for real time simulation. For all digital simulation estimates of the required speed in terms of equivalent operations per second are developed based on the complexity of the equations and the required intergration frame rates. For both conventional hybrid simulation and hybrid simulation using time-shared analog elements the amount of required equipment is estimated along with a consideration of the dynamic errors. Conventional hybrid mechanization using analog simulation of those rotor equations which involve rotor-spin frequencies (this consititutes the bulk of the equations) requires too much analog equipment. Hybrid simulation using time-sharing techniques for the analog elements appears possible with a reasonable amount of analog equipment. All-digital simulation with affordable general-purpose computers is not possible because of speed limitations, but specially configured digital computers do have the required speed and consitute the recommended approach.
NASA Technical Reports Server (NTRS)
1973-01-01
Techniques are considered which would be used to characterize areospace computers with the space shuttle application as end usage. The system level digital problems which have been encountered and documented are surveyed. From the large cross section of tests, an optimum set is recommended that has a high probability of discovering documented system level digital problems within laboratory environments. Defined is a baseline hardware, software system which is required as a laboratory tool to test aerospace computers. Hardware and software baselines and additions necessary to interface the UTE to aerospace computers for test purposes are outlined.
El-Shafey, A; Kassab, A
2013-04-01
The purpose of the present study was to provide a detailed computed tomography (CT) and cross-sectional anatomic reference of the normal metatarsus and digits for the camel and buffalo, as well as to compare between metatarsus and digits in these animals to outstand a basis for diagnosis of their diseases. Advantages, including depiction of detailed cross-sectional anatomy, improved contrast resolution and computer reformatting, make it a potentially valuable diagnostic technique. The hind limbs of 12 healthy adult camel and buffalo were used. Clinically relevant anatomic structures were identified and labelled at each level in the corresponding images (CT and anatomic slices). CT images were used to identify the bony and soft tissue structures of the metatarsus and digits. The knowledge of normal anatomy of the camel and buffalo metatarsus and digits would serve as initial reference to the evaluation of CT images in these species. © 2012 Blackwell Verlag GmbH.
Digital Humanities: What Can Libraries Offer?
ERIC Educational Resources Information Center
Wong, Shun Han Rebekah
2016-01-01
The collaborative aspect of digital humanities is one of the core values of the field. Specialists and organizations involved in digital humanities partnerships may include individual scholars focusing on a particular area, multiple scholars across disciplines, computer scientists, or digital humanities centers. Through a quantitative analysis of…
NASA Technical Reports Server (NTRS)
1978-01-01
A triplex digital flight control system was installed in a NASA F-8C airplane to provide fail operate, full authority control. The triplex digital computers and interface circuitry process the pilot commands and aircraft motion feedback parameters according to the selected control laws, and they output the surface commands as an analog signal to the servoelectronics for position control of the aircraft's power actuators. The system and theory of operation of the computer by pass and servoelectronics are described and an automated ground test for each axis is included.
The computation of pi to 29,360,000 decimal digits using Borweins' quartically convergent algorithm
NASA Technical Reports Server (NTRS)
Bailey, David H.
1988-01-01
The quartically convergent numerical algorithm developed by Borwein and Borwein (1987) for 1/pi is implemented via a prime-modulus-transform multiprecision technique on the NASA Ames Cray-2 supercomputer to compute the first 2.936 x 10 to the 7th digits of the decimal expansion of pi. The history of pi computations is briefly recalled; the most recent algorithms are characterized; the implementation procedures are described; and samples of the output listing are presented. Statistical analyses show that the present decimal expansion is completely random, with only acceptable numbers of long repeating strings and single-digit runs.
Distributing digital video to multiple computers
Murray, James A.
2004-01-01
Video is an effective teaching tool, and live video microscopy is especially helpful in teaching dissection techniques and the anatomy of small neural structures. Digital video equipment is more affordable now and allows easy conversion from older analog video devices. I here describe a simple technique for bringing digital video from one camera to all of the computers in a single room. This technique allows students to view and record the video from a single camera on a microscope. PMID:23493464
Digital Immersive Virtual Environments and Instructional Computing
ERIC Educational Resources Information Center
Blascovich, Jim; Beall, Andrew C.
2010-01-01
This article reviews theory and research relevant to the development of digital immersive virtual environment-based instructional computing systems. The review is organized within the context of a multidimensional model of social influence and interaction within virtual environments that models the interaction of four theoretical factors: theory…
A system for automatic analysis of blood pressure data for digital computer entry
NASA Technical Reports Server (NTRS)
Miller, R. L.
1972-01-01
Operation of automatic blood pressure data system is described. Analog blood pressure signal is analyzed by three separate circuits, systolic, diastolic, and cycle defect. Digital computer output is displayed on teletype paper tape punch and video screen. Illustration of system is included.
Micro computed tomography (CT) scanned anatomical gateway to insect pest bioinformatics
USDA-ARS?s Scientific Manuscript database
An international collaboration to establish an interactive Digital Video Library for a Systems Biology Approach to study the Asian citrus Psyllid and psyllid genomics/proteomics interactions is demonstrated. Advances in micro-CT, digital computed tomography (CT) scan uses X-rays to make detailed pic...
Peering into the Future of Advertising.
ERIC Educational Resources Information Center
Hsia, H. J.
All areas in mass communications (i.e., newspapers, magazines, television, radio, films, photos, and books) will be transformed because of the increasing sophistication of computer users, the decreasing costs for interactive computer systems, and the global adoption of integrated services digital networks (ISDN). ISDN refer to the digitization of…
Teaching Multimedia Data Protection through an International Online Competition
ERIC Educational Resources Information Center
Battisti, F.; Boato, G.; Carli, M.; Neri, A.
2011-01-01
Low-cost personal computers, wireless access technologies, the Internet, and computer-equipped classrooms allow the design of novel and complementary methodologies for teaching digital information security in electrical engineering curricula. The challenges of the current digital information era require experts who are effectively able to…
Photography/Digital Imaging: Parallel & Paradoxical Histories.
ERIC Educational Resources Information Center
Witte, Mary Stieglitz
With the introduction of photography and photomechanical printing processes in the 19th century, the first age of machine pictures and reproductions emerged. The 20th century introduced computer image processing systems, creating a digital imaging revolution. Rather than concentrating on the adversarial aspects of the computer's influence on…
NASA Technical Reports Server (NTRS)
1973-01-01
Design and development efforts for a spaceborne modular computer system are reported. An initial baseline description is followed by an interface design that includes definition of the overall system response to all classes of failure. Final versions for the register level designs for all module types were completed. Packaging, support and control executive software, including memory utilization estimates and design verification plan, were formalized to insure a soundly integrated design of the digital computer system.
Photogrammetry and computer-aided piping design
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keneflick, J.F.; Chirillo, R.D.
1985-02-18
Three-dimensional measurements taken from photographs of a plant model can be digitized and linked with computer-aided piping design. This can short-cut the design and construction of new plants and expedite repair and retrofitting projects. Some designers bridge the gap between model and computer by digitizing from orthographic prints obtained via orthography or the laser scanning of model sections. Such valve or fitting then processed is described in this paper. The marriage of photogrammetry and computer-aided piping design can economically produce such numerical drawings.
Image analysis and machine learning in digital pathology: Challenges and opportunities.
Madabhushi, Anant; Lee, George
2016-10-01
With the rise in whole slide scanner technology, large numbers of tissue slides are being scanned and represented and archived digitally. While digital pathology has substantial implications for telepathology, second opinions, and education there are also huge research opportunities in image computing with this new source of "big data". It is well known that there is fundamental prognostic data embedded in pathology images. The ability to mine "sub-visual" image features from digital pathology slide images, features that may not be visually discernible by a pathologist, offers the opportunity for better quantitative modeling of disease appearance and hence possibly improved prediction of disease aggressiveness and patient outcome. However the compelling opportunities in precision medicine offered by big digital pathology data come with their own set of computational challenges. Image analysis and computer assisted detection and diagnosis tools previously developed in the context of radiographic images are woefully inadequate to deal with the data density in high resolution digitized whole slide images. Additionally there has been recent substantial interest in combining and fusing radiologic imaging and proteomics and genomics based measurements with features extracted from digital pathology images for better prognostic prediction of disease aggressiveness and patient outcome. Again there is a paucity of powerful tools for combining disease specific features that manifest across multiple different length scales. The purpose of this review is to discuss developments in computational image analysis tools for predictive modeling of digital pathology images from a detection, segmentation, feature extraction, and tissue classification perspective. We discuss the emergence of new handcrafted feature approaches for improved predictive modeling of tissue appearance and also review the emergence of deep learning schemes for both object detection and tissue classification. We also briefly review some of the state of the art in fusion of radiology and pathology images and also combining digital pathology derived image measurements with molecular "omics" features for better predictive modeling. The review ends with a brief discussion of some of the technical and computational challenges to be overcome and reflects on future opportunities for the quantitation of histopathology. Copyright © 2016 Elsevier B.V. All rights reserved.
Digital terrain tapes: user guide
,
1980-01-01
DMATC's digital terrain tapes are a by-product of the agency's efforts to streamline the production of raised-relief maps. In the early 1960's DMATC developed the Digital Graphics Recorder (DGR) system that introduced new digitizing techniques and processing methods into the field of three-dimensional mapping. The DGR system consisted of an automatic digitizing table and a computer system that recorded a grid of terrain elevations from traces of the contour lines on standard topographic maps. A sequence of computer accuracy checks was performed and then the elevations of grid points not intersected by contour lines were interpolated. The DGR system produced computer magnetic tapes which controlled the carving of plaster forms used to mold raised-relief maps. It was realized almost immediately that this relatively simple tool for carving plaster molds had enormous potential for storing, manipulating, and selectively displaying (either graphically or numerically) a vast number of terrain elevations. As the demand for the digital terrain tapes increased, DMATC began developing increasingly advanced digitizing systems and now operates the Digital Topographic Data Collection System (DTDCS). With DTDCS, two types of data elevations as contour lines and points, and stream and ridge lines are sorted, matched, and resorted to obtain a grid of elevation values for every 0.01 inch on each map (approximately 200 feet on the ground). Undefined points on the grid are found by either linear or or planar interpolation.
Floating-point system quantization errors in digital control systems
NASA Technical Reports Server (NTRS)
Phillips, C. L.; Vallely, D. P.
1978-01-01
This paper considers digital controllers (filters) operating in floating-point arithmetic in either open-loop or closed-loop systems. A quantization error analysis technique is developed, and is implemented by a digital computer program that is based on a digital simulation of the system. The program can be integrated into existing digital simulations of a system.
[Possibilities of use of digital imaging in forensic medicine].
Gaval'a, P; Ivicsics, I; Mlynár, J; Novomeský, F
2005-07-01
Based on the daily practice with digital photography and documentation, the authors point out the achievements of the computer technologies implementation to the practice of forensic medicine. The modern methods of imaging, especially the digital photography, offer a wide spectrum of use in forensic medicine--the digital documentation and archivation of autopsy findings, the possibility of immediate consultation of findings with another experts via Internet, and many others. Another possibility is a creation of digital photographic atlas of forensic medicine as a useful aid in pre- and postgradual study. Thus the application of the state-of-the-art computer technologies to the forensic medicine discloses the unknown before possibilities for further development of such a discipline of human medical sciences.
Digital avionics design and reliability analyzer
NASA Technical Reports Server (NTRS)
1981-01-01
The description and specifications for a digital avionics design and reliability analyzer are given. Its basic function is to provide for the simulation and emulation of the various fault-tolerant digital avionic computer designs that are developed. It has been established that hardware emulation at the gate-level will be utilized. The primary benefit of emulation to reliability analysis is the fact that it provides the capability to model a system at a very detailed level. Emulation allows the direct insertion of faults into the system, rather than waiting for actual hardware failures to occur. This allows for controlled and accelerated testing of system reaction to hardware failures. There is a trade study which leads to the decision to specify a two-machine system, including an emulation computer connected to a general-purpose computer. There is also an evaluation of potential computers to serve as the emulation computer.
Design requirements for ubiquitous computing environments for healthcare professionals.
Bång, Magnus; Larsson, Anders; Eriksson, Henrik
2004-01-01
Ubiquitous computing environments can support clinical administrative routines in new ways. The aim of such computing approaches is to enhance routine physical work, thus it is important to identify specific design requirements. We studied healthcare professionals in an emergency room and developed the computer-augmented environment NOSTOS to support teamwork in that setting. NOSTOS uses digital pens and paper-based media as the primary input interface for data capture and as a means of controlling the system. NOSTOS also includes a digital desk, walk-up displays, and sensor technology that allow the system to track documents and activities in the workplace. We propose a set of requirements and discuss the value of tangible user interfaces for healthcare personnel. Our results suggest that the key requirements are flexibility in terms of system usage and seamless integration between digital and physical components. We also discuss how ubiquitous computing approaches like NOSTOS can be beneficial in the medical workplace.
Visual Form Perception Can Be a Cognitive Correlate of Lower Level Math Categories for Teenagers.
Cui, Jiaxin; Zhang, Yiyun; Cheng, Dazhi; Li, Dawei; Zhou, Xinlin
2017-01-01
Numerous studies have assessed the cognitive correlates of performance in mathematics, but little research has been conducted to systematically examine the relations between visual perception as the starting point of visuospatial processing and typical mathematical performance. In the current study, we recruited 223 seventh graders to perform a visual form perception task (figure matching), numerosity comparison, digit comparison, exact computation, approximate computation, and curriculum-based mathematical achievement tests. Results showed that, after controlling for gender, age, and five general cognitive processes (choice reaction time, visual tracing, mental rotation, spatial working memory, and non-verbal matrices reasoning), visual form perception had unique contributions to numerosity comparison, digit comparison, and exact computation, but had no significant relation with approximate computation or curriculum-based mathematical achievement. These results suggest that visual form perception is an important independent cognitive correlate of lower level math categories, including the approximate number system, digit comparison, and exact computation.
Techniques for digital enhancement of Landsat MSS data using an Apple II+ microcomputer
NASA Technical Reports Server (NTRS)
Harrington, J. A., Jr.; Cartin, K. F.
1984-01-01
The information provided by remotely sensed data collected from orbiting platforms has been useful in many research fields. Particularly convenient for evaluation are generally digital data stored on computer compatible tapes (CCT's). The major advantages of CCT's are the quality of the data and the accessibility to computer manipulation. Minicomputer systems are widely used for the required computer processing operations. However, microprocessor-related technological advances make it now possible to process CCT data with computing systems which can be obtained at a much lower price than minicomputer systems. A detailed description is provided of the design considerations of a microcomputer-based Digital Image Analysis System (DIAS). Particular attention is given to the algorithms which are incorporated for eighter edge enhancement or smoothing Landsat multispectral scanner data.
Reduction of lithologic-log data to numbers for use in the digital computer
Morgan, C.O.; McNellis, J.M.
1971-01-01
The development of a standardized system for conveniently coding lithologic-log data for use in the digital computer has long been needed. The technique suggested involves a reduction of the original written alphanumeric log to a numeric log by use of computer programs. This numeric log can then be retrieved as a written log, interrogated for pertinent information, or analyzed statistically. ?? 1971 Plenum Publishing Corporation.
A Computational Model of Selection by Consequences
ERIC Educational Resources Information Center
McDowell, J. J.
2004-01-01
Darwinian selection by consequences was instantiated in a computational model that consisted of a repertoire of behaviors undergoing selection, reproduction, and mutation over many generations. The model in effect created a digital organism that emitted behavior continuously. The behavior of this digital organism was studied in three series of…
An Undergraduate Experiment in Alarm System Design.
ERIC Educational Resources Information Center
Martini, R. A.; And Others
1988-01-01
Describes an experiment involving data acquisition by a computer, digital signal transmission from the computer to a digital logic circuit and signal interpretation by this circuit. The system is being used at the Illinois Institute of Technology. Discusses the fundamental concepts involved. Demonstrates the alarm experiment as it is used in…
NASA Technical Reports Server (NTRS)
Simon, M. K.
1980-01-01
A technique is presented for generating phase plane plots on a digital computer which circumvents the difficulties associated with more traditional methods of numerical solving nonlinear differential equations. In particular, the nonlinear differential equation of operation is formulated.
An Undergraduate Electrical Engineering Course on Computer Organization.
ERIC Educational Resources Information Center
Commission on Engineering Education, Washington, DC.
Outlined is an undergraduate electrical engineering course on computer organization designed to meet the need for electrical engineers familiar with digital system design. The program includes both hardware and software aspects of digital systems essential to design function and correlates design and organizational aspects of the subject. The…
Definition and trade-off study of reconfigurable airborne digital computer system organizations
NASA Technical Reports Server (NTRS)
Conn, R. B.
1974-01-01
A highly-reliable, fault-tolerant reconfigurable computer system for aircraft applications was developed. The development and application reliability and fault-tolerance assessment techniques are described. Particular emphasis is placed on the needs of an all-digital, fly-by-wire control system appropriate for a passenger-carrying airplane.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-02
... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Software Requirement Specifications for Digital Computer Software Used in Safety Systems of Nuclear Power Plants AGENCY: Nuclear Regulatory Commission... issuing a revised regulatory guide (RG), revision 1 of RG 1.172, ``Software Requirement Specifications for...
APQ-102 imaging radar digital image quality study
NASA Technical Reports Server (NTRS)
Griffin, C. R.; Estes, J. M.
1982-01-01
A modified APQ-102 sidelooking radar collected synthetic aperture radar (SAR) data which was digitized and recorded on wideband magnetic tape. These tapes were then ground processed into computer compatible tapes (CCT's). The CCT's may then be processed into high resolution radar images by software on the CYBER computer.
Kautiainen, S; Koivusilta, L; Lintonen, T; Virtanen, S M; Rimpelä, A
2005-08-01
The prevalence of overweight and obesity has increased among children and adolescents, as well as among adults, and television viewing has been suggested as one cause. Playing digital games (video, computer and console games), or using computer may be other sedentary behaviors related to the development of overweight and obesity. To study the relationships of times spent on viewing television, playing digital games and using computer to overweight among Finnish adolescents. Mailed cross-sectional survey. Nationally representative samples of 14-, 16-, and 18-y-old (N=6515, response rate 70%) in 2001. Overweight and obesity were assessed by body mass index (BMI). The respondents reported times spent daily on viewing television, playing digital games (video, computer and console games) and using computer (for e-mail, writing and surfing). Data on timing of biological maturation, intensity of weekly physical activity and family's socio economic status were taken into account in the statistical analyses. Increased times spent on viewing television and using computer were associated with increased prevalence of overweight (obesity inclusive) among girls: compared to girls viewing television <1 h daily, the adjusted odds ratio (OR) for being overweight was 1.4 when spending 1-3 h, and 2.0 when spending > or =4 h daily on viewing television. In girls using computer > or =1 h daily, the OR for being overweight was 1.5 compared to girls using computer <1 h daily. The results were similar in boys, although not statistically significant. Time spent on playing digital games was not associated with overweight. Overweight was associated with using information and communication technology (ICT), but only with certain forms of ICT. Increased use of ICT may be one factor explaining the increased prevalence of overweight and obesity at the population level, at least in girls. Playing digital games was not related to overweight, perhaps by virtue of game playing being less sedentary or related to a different lifestyle than viewing television and using computer.
Digital Libraries Are Much More than Digitized Collections.
ERIC Educational Resources Information Center
Peters, Peter Evan
1995-01-01
The digital library encompasses the application of high-performance computers and networks to the production, distribution, management, and use of knowledge in research and education. A joint project by three federal agencies, which is investing in digital library initiatives at six universities, is discussed. A sidebar provides issues to consider…
An Interactive Graphics Program for Investigating Digital Signal Processing.
ERIC Educational Resources Information Center
Miller, Billy K.; And Others
1983-01-01
Describes development of an interactive computer graphics program for use in teaching digital signal processing. The program allows students to interactively configure digital systems on a monitor display and observe their system's performance by means of digital plots on the system's outputs. A sample program run is included. (JN)
(In)Forming: The Affordances of Digital Fabrication in Architectural Education
ERIC Educational Resources Information Center
Cabrinha, Mark Newell
2010-01-01
This research focuses on the effect of technology on the culture of architectural education through the lens of digital fabrication (CAD/CAM). As the computer was introduced into design education long before digital fabrication was accessible, design culture has prioritized image over material experience. Digital fabrication enables a material…
Digital Libraries--Methods and Applications
ERIC Educational Resources Information Center
Huang, Kuo Hung, Ed.
2011-01-01
Digital library is commonly seen as a type of information retrieval system which stores and accesses digital content remotely via computer networks. However, the vision of digital libraries is not limited to technology or management, but user experience. This book is an attempt to share the practical experiences of solutions to the operation of…
Preliminary development of digital signal processing in microwave radiometers
NASA Technical Reports Server (NTRS)
Stanley, W. D.
1980-01-01
Topics covered involve a number of closely related tasks including: the development of several control loop and dynamic noise model computer programs for simulating microwave radiometer measurements; computer modeling of an existing stepped frequency radiometer in an effort to determine its optimum operational characteristics; investigation of the classical second order analog control loop to determine its ability to reduce the estimation error in a microwave radiometer; investigation of several digital signal processing unit designs; initiation of efforts to develop required hardware and software for implementation of the digital signal processing unit; and investigation of the general characteristics and peculiarities of digital processing noiselike microwave radiometer signals.
[The procedure for documentation of digital images in forensic medical histology].
Putintsev, V A; Bogomolov, D V; Fedulova, M V; Gribunov, Iu P; Kul'bitskiĭ, B N
2012-01-01
This paper is devoted to the novel computer technologies employed in the studies of histological preparations. These technologies allow to visualize digital images, structurize the data obtained and store the results in computer memory. The authors emphasize the necessity to properly document digital images obtained during forensic-histological studies and propose the procedure for the formulation of electronic documents in conformity with the relevant technical and legal requirements. It is concluded that the use of digital images as a new study object permits to obviate the drawbacks inherent in the work with the traditional preparations and pass from descriptive microscopy to their quantitative analysis.
Memory device for two-dimensional radiant energy array computers
NASA Technical Reports Server (NTRS)
Schaefer, D. H.; Strong, J. P., III (Inventor)
1977-01-01
A memory device for two dimensional radiant energy array computers was developed, in which the memory device stores digital information in an input array of radiant energy digital signals that are characterized by ordered rows and columns. The memory device contains a radiant energy logic storing device having a pair of input surface locations for receiving a pair of separate radiant energy digital signal arrays and an output surface location adapted to transmit a radiant energy digital signal array. A regenerative feedback device that couples one of the input surface locations to the output surface location in a manner for causing regenerative feedback is also included
Malta Barbosa, João; Tovar, Nick; A Tuesta, Pablo; Hirata, Ronaldo; Guimarães, Nuno; Romanini, José C; Moghadam, Marjan; Coelho, Paulo G; Jahangiri, Leila
2017-07-08
This work aims to present a pilot study of a non-destructive dental histo-anatomical analysis technique as well as to push the boundaries of the presently available restorative workflows for the fabrication of highly customized ceramic restorations. An extracted human maxillary central incisor was subject to a micro computed tomography scan and the acquired data was transferred into a workstation, reconstructed, segmented, evaluated and later imported into a Computer-Aided Design/Computer-Aided Manufacturing software for the fabrication of a ceramic resin-bonded prosthesis. The obtained prosthesis presented an encouraging optical behavior and was used clinically as final restoration. The digitally layered restorative replication of natural tooth morphology presents today as a clear possibility. New clinical and laboratory-fabricated, biologically inspired digital restorative protocols are to be expected in the near future. The digitally layered restorative replication of natural tooth morphology presents today as a clear possibility. This pilot study may represent a stimulus for future research and applications of digital imaging as well as digital restorative workflows in service of esthetic dentistry. © 2017 Wiley Periodicals, Inc.
Implementation of a Target State Estimator for the Air-to-Air Attack Mode of the AFTI/F-16.
1987-12-01
presents a discussion of the portion of the AFTI/F-16 aircraft relative to this thesis, including sensors and the digital flight control system ( DFCS ...system ( DFCS ). All sensor data are digitized and sent to one or more digital computers for processing. The flight control computers convert flight...the square of the magnitude of the target’s inertial turn rate, is developed from the application of the Coriolis theorem, written as Id Td dt dt
V/STOL AND digital avionics system for UH-1H
NASA Technical Reports Server (NTRS)
Liden, S.
1978-01-01
A hardware and software system for the Bell UH-1H helicopter was developed that provides sophisticated navigation, guidance, control, display, and data acquisition capabilities for performing terminal area navigation, guidance and control research. Two Sperry 1819B general purpose digital computers were used. One contains the development software that performs all the specified system flight computations. The second computer is available to NASA for experimental programs that run simultaneously with the other computer programs and which may, at the push of a button, replace selected computer computations. Other features that provide research flexibility include keyboard selectable gains and parameters and software generated alphanumeric and CRT displays.
Computed tomographic contrast tenography of the digital flexor tendon sheath of the equine hindlimb.
Agass, Rachel; Dixon, Jonathon; Fraser, Barny
2018-05-01
Pre-surgical investigation of digital flexor tendon sheath pathology remains challenging with current standard imaging techniques. The aim of this prospective, anatomical, pilot study was to describe the anatomy of the equine hind limb digital flexor tendon sheath using a combination of computed tomography (CT) and computed tomographic contrast tenography in clinically normal cadaver limbs. Ten pairs of hind limbs with no external abnormalities were examined from the level of the tarsometatarsal joint distally. Limbs initially underwent non-contrast CT examination using 120 kVp, 300 mAs, and 1.5 mm slice thickness. Sixty millilitres of ioversol iodinated contrast media and saline (final concentration 100 mg/ml) were injected using a basilar sesamoidean approach. The computed tomographic contrast tenography examination was then repeated, before dissection of the specimens to compare gross and imaging findings. The combined CT and computed tomographic contrast tenography examinations provided excellent anatomical detail of intra-thecal structures. The borders of the superficial and deep digital flexor tendons, and the manica flexoria were consistently identifiable in all limbs. Detailed anatomy including that of the mesotenons, two of which are previously undescribed, and the plantar annular ligament were also consistently identifiable. Dissection of all 10 pairs of limbs revealed there to be no pathology, in accordance with the imaging findings. In conclusion, the combination of CT and computed tomographic contrast tenography may be useful adjunctive diagnostic techniques to define digital flexor tendon sheath pathology prior to surgical exploration in horses. © 2017 American College of Veterinary Radiology.
NASA Astrophysics Data System (ADS)
Papers are presented on ISDN, mobile radio systems and techniques for digital connectivity, centralized and distributed algorithms in computer networks, communications networks, quality assurance and impact on cost, adaptive filters in communications, the spread spectrum, signal processing, video communication techniques, and digital satellite services. Topics discussed include performance evaluation issues for integrated protocols, packet network operations, the computer network theory and multiple-access, microwave single sideband systems, switching architectures, fiber optic systems, wireless local communications, modulation, coding, and synchronization, remote switching, software quality, transmission, and expert systems in network operations. Consideration is given to wide area networks, image and speech processing, office communications application protocols, multimedia systems, customer-controlled network operations, digital radio systems, channel modeling and signal processing in digital communications, earth station/on-board modems, computer communications system performance evaluation, source encoding, compression, and quantization, and adaptive communications systems.
NASA Technical Reports Server (NTRS)
Lillesand, T. M.; Meisner, D. E. (Principal Investigator)
1980-01-01
An investigation was conducted into ways to improve the involvement of state and local user personnel in the digital image analysis process by isolating those elements of the analysis process which require extensive involvement by field personnel and providing means for performing those activities apart from a computer facility. In this way, the analysis procedure can be converted from a centralized activity focused on a computer facility to a distributed activity in which users can interact with the data at the field office level or in the field itself. A general image processing software was developed on the University of Minnesota computer system (Control Data Cyber models 172 and 74). The use of color hardcopy image data as a primary medium in supervised training procedures was investigated and digital display equipment and a coordinate digitizer were procured.
Study on the application of mobile internet cloud computing platform
NASA Astrophysics Data System (ADS)
Gong, Songchun; Fu, Songyin; Chen, Zheng
2012-04-01
The innovative development of computer technology promotes the application of the cloud computing platform, which actually is the substitution and exchange of a sort of resource service models and meets the needs of users on the utilization of different resources after changes and adjustments of multiple aspects. "Cloud computing" owns advantages in many aspects which not merely reduce the difficulties to apply the operating system and also make it easy for users to search, acquire and process the resources. In accordance with this point, the author takes the management of digital libraries as the research focus in this paper, and analyzes the key technologies of the mobile internet cloud computing platform in the operation process. The popularization and promotion of computer technology drive people to create the digital library models, and its core idea is to strengthen the optimal management of the library resource information through computers and construct an inquiry and search platform with high performance, allowing the users to access to the necessary information resources at any time. However, the cloud computing is able to promote the computations within the computers to distribute in a large number of distributed computers, and hence implement the connection service of multiple computers. The digital libraries, as a typical representative of the applications of the cloud computing, can be used to carry out an analysis on the key technologies of the cloud computing.
Optical information processing at NASA Ames Research Center
NASA Technical Reports Server (NTRS)
Reid, Max B.; Bualat, Maria G.; Cho, Young C.; Downie, John D.; Gary, Charles K.; Ma, Paul W.; Ozcan, Meric; Pryor, Anna H.; Spirkovska, Lilly
1993-01-01
The combination of analog optical processors with digital electronic systems offers the potential of tera-OPS computational performance, while often requiring less power and weight relative to all-digital systems. NASA is working to develop and demonstrate optical processing techniques for on-board, real time science and mission applications. Current research areas and applications under investigation include optical matrix processing for space structure vibration control and the analysis of Space Shuttle Main Engine plume spectra, optical correlation-based autonomous vision for robotic vehicles, analog computation for robotic path planning, free-space optical interconnections for information transfer within digital electronic computers, and multiplexed arrays of fiber optic interferometric sensors for acoustic and vibration measurements.
A computational- And storage-cloud for integration of biodiversity collections
Matsunaga, A.; Thompson, A.; Figueiredo, R. J.; Germain-Aubrey, C.C; Collins, M.; Beeman, R.S; Macfadden, B.J.; Riccardi, G.; Soltis, P.S; Page, L. M.; Fortes, J.A.B
2013-01-01
A core mission of the Integrated Digitized Biocollections (iDigBio) project is the building and deployment of a cloud computing environment customized to support the digitization workflow and integration of data from all U.S. nonfederal biocollections. iDigBio chose to use cloud computing technologies to deliver a cyberinfrastructure that is flexible, agile, resilient, and scalable to meet the needs of the biodiversity community. In this context, this paper describes the integration of open source cloud middleware, applications, and third party services using standard formats, protocols, and services. In addition, this paper demonstrates the value of the digitized information from collections in a broader scenario involving multiple disciplines.
Hydraulic logic gates: building a digital water computer
NASA Astrophysics Data System (ADS)
Taberlet, Nicolas; Marsal, Quentin; Ferrand, Jérémy; Plihon, Nicolas
2018-03-01
In this article, we propose an easy-to-build hydraulic machine which serves as a digital binary computer. We first explain how an elementary adder can be built from test tubes and pipes (a cup filled with water representing a 1, and empty cup a 0). Using a siphon and a slow drain, the proposed setup combines AND and XOR logical gates in a single device which can add two binary digits. We then show how these elementary units can be combined to construct a full 4-bit adder. The sequencing of the computation is discussed and a water clock can be incorporated so that the machine can run without any exterior intervention.
Method and apparatus for digitally based high speed x-ray spectrometer
Warburton, W.K.; Hubbard, B.
1997-11-04
A high speed, digitally based, signal processing system which accepts input data from a detector-preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system achieves high throughputs at low cost by dividing the required digital processing steps between a ``hardwired`` processor implemented in combinatorial digital logic, which detects the presence of the x-ray signals in the digitized data stream and extracts filtered estimates of their amplitudes, and a programmable digital signal processing computer, which refines the filtered amplitude estimates and bins them to produce the desired spectral analysis. One set of algorithms allow this hybrid system to match the resolution of analog systems while operating at much higher data rates. A second set of algorithms implemented in the processor allow the system to be self calibrating as well. The same processor also handles the interface to an external control computer. 19 figs.
Method and apparatus for digitally based high speed x-ray spectrometer
Warburton, William K.; Hubbard, Bradley
1997-01-01
A high speed, digitally based, signal processing system which accepts input data from a detector-preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system achieves high throughputs at low cost by dividing the required digital processing steps between a "hardwired" processor implemented in combinatorial digital logic, which detects the presence of the x-ray signals in the digitized data stream and extracts filtered estimates of their amplitudes, and a programmable digital signal processing computer, which refines the filtered amplitude estimates and bins them to produce the desired spectral analysis. One set of algorithms allow this hybrid system to match the resolution of analog systems while operating at much higher data rates. A second set of algorithms implemented in the processor allow the system to be self calibrating as well. The same processor also handles the interface to an external control computer.
Optical design of cipher block chaining (CBC) encryption mode by using digital holography
NASA Astrophysics Data System (ADS)
Gil, Sang Keun; Jeon, Seok Hee; Jung, Jong Rae; Kim, Nam
2016-03-01
We propose an optical design of cipher block chaining (CBC) encryption by using digital holographic technique, which has higher security than the conventional electronic method because of the analog-type randomized cipher text with 2-D array. In this paper, an optical design of CBC encryption mode is implemented by 2-step quadrature phase-shifting digital holographic encryption technique using orthogonal polarization. A block of plain text is encrypted with the encryption key by applying 2-step phase-shifting digital holography, and it is changed into cipher text blocks which are digital holograms. These ciphered digital holograms with the encrypted information are Fourier transform holograms and are recorded on CCDs with 256 gray levels quantized intensities. The decryption is computed by these encrypted digital holograms of cipher texts, the same encryption key and the previous cipher text. Results of computer simulations are presented to verify that the proposed method shows the feasibility in the high secure CBC encryption system.
Image compression system and method having optimized quantization tables
NASA Technical Reports Server (NTRS)
Ratnakar, Viresh (Inventor); Livny, Miron (Inventor)
1998-01-01
A digital image compression preprocessor for use in a discrete cosine transform-based digital image compression device is provided. The preprocessor includes a gathering mechanism for determining discrete cosine transform statistics from input digital image data. A computing mechanism is operatively coupled to the gathering mechanism to calculate a image distortion array and a rate of image compression array based upon the discrete cosine transform statistics for each possible quantization value. A dynamic programming mechanism is operatively coupled to the computing mechanism to optimize the rate of image compression array against the image distortion array such that a rate-distortion-optimal quantization table is derived. In addition, a discrete cosine transform-based digital image compression device and a discrete cosine transform-based digital image compression and decompression system are provided. Also, a method for generating a rate-distortion-optimal quantization table, using discrete cosine transform-based digital image compression, and operating a discrete cosine transform-based digital image compression and decompression system are provided.
Raji, A R; Sardari, K; Mohammadi, H R
2008-06-01
The purpose of this study was to define the structures of the digits and hoof in Holstein dairy cattle by using computed tomography scan (CT scan). Transverse, sagittal and dorsoplantar CT images of two isolated cattle cadaver digits were obtained using a Siemens ARTX2 Somatom. The CT images were compared to corresponding frozen cross-sections. Relevant anatomical structures were identified and labelled at each level. The CT images provided anatomical detail of the digits and hoof in Holstein dairy cattle. Transversal images provided excellent depiction of anatomical structures when compared to corresponding frozen cross-sections. The information presented in this paper would serve as an initial reference to the evaluation of CT images of the digits and hoof in Holstein dairy cattle.
Evaluation of user input methods for manipulating a tablet personal computer in sterile techniques.
Yamada, Akira; Komatsu, Daisuke; Suzuki, Takeshi; Kurozumi, Masahiro; Fujinaga, Yasunari; Ueda, Kazuhiko; Kadoya, Masumi
2017-02-01
To determine a quick and accurate user input method for manipulating tablet personal computers (PCs) in sterile techniques. We evaluated three different manipulation methods, (1) Computer mouse and sterile system drape, (2) Fingers and sterile system drape, and (3) Digitizer stylus and sterile ultrasound probe cover with a pinhole, in terms of the central processing unit (CPU) performance, manipulation performance, and contactlessness. A significant decrease in CPU score ([Formula: see text]) and an increase in CPU temperature ([Formula: see text]) were observed when a system drape was used. The respective mean times taken to select a target image from an image series (ST) and the mean times for measuring points on an image (MT) were [Formula: see text] and [Formula: see text] s for the computer mouse method, [Formula: see text] and [Formula: see text] s for the finger method, and [Formula: see text] and [Formula: see text] s for the digitizer stylus method, respectively. The ST for the finger method was significantly longer than for the digitizer stylus method ([Formula: see text]). The MT for the computer mouse method was significantly longer than for the digitizer stylus method ([Formula: see text]). The mean success rate for measuring points on an image was significantly lower for the finger method when the diameter of the target was equal to or smaller than 8 mm than for the other methods. No significant difference in the adenosine triphosphate amount at the surface of the tablet PC was observed before, during, or after manipulation via the digitizer stylus method while wearing starch-powdered sterile gloves ([Formula: see text]). Quick and accurate manipulation of tablet PCs in sterile techniques without CPU load is feasible using a digitizer stylus and sterile ultrasound probe cover with a pinhole.
NASA Astrophysics Data System (ADS)
Wang, Rui
It is known that high intensity radiated fields (HIRF) can produce upsets in digital electronics, and thereby degrade the performance of digital flight control systems. Such upsets, either from natural or man-made sources, can change data values on digital buses and memory and affect CPU instruction execution. HIRF environments are also known to trigger common-mode faults, affecting nearly-simultaneously multiple fault containment regions, and hence reducing the benefits of n-modular redundancy and other fault-tolerant computing techniques. Thus, it is important to develop models which describe the integration of the embedded digital system, where the control law is implemented, as well as the dynamics of the closed-loop system. In this dissertation, theoretical tools are presented to analyze the relationship between the design choices for a class of distributed recoverable computing platforms and the tracking performance degradation of a digital flight control system implemented on such a platform while operating in a HIRF environment. Specifically, a tractable hybrid performance model is developed for a digital flight control system implemented on a computing platform inspired largely by the NASA family of fault-tolerant, reconfigurable computer architectures known as SPIDER (scalable processor-independent design for enhanced reliability). The focus will be on the SPIDER implementation, which uses the computer communication system known as ROBUS-2 (reliable optical bus). A physical HIRF experiment was conducted at the NASA Langley Research Center in order to validate the theoretical tracking performance degradation predictions for a distributed Boeing 747 flight control system subject to a HIRF environment. An extrapolation of these results for scenarios that could not be physically tested is also presented.
ERIC Educational Resources Information Center
Kilickaya, Ferit; Krajka, Jaroslaw
2012-01-01
Both teacher- and learner-made computer visuals are quite extensively reported in Computer-Assisted Language Learning literature, for instance, filming interviews, soap operas or mini-documentaries, creating storyboard projects, authoring podcasts and vodcasts, designing digital stories. Such student-made digital assets are used to present to…
ERIC Educational Resources Information Center
Johnson, James E.; Christie, James F.
2009-01-01
This article examines how play is affected by computers and digital toys. Research indicates that when computer software targeted at children is problem-solving oriented and open-ended, children tend to engage in creative play and interact with peers in a positive manner. On the other hand, drill-and-practice programs can be quite boring and limit…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-06
... Documents Access and Management System (ADAMS): You may access publicly available documents online in the... Management Plans for Digital Computer Software used in Safety Systems of Nuclear Power Plants,'' issued for... Used in Safety Systems of Nuclear Power Plants AGENCY: Nuclear Regulatory Commission. ACTION: Revision...
Design Principles for "Thriving in Our Digital World": A High School Computer Science Course
ERIC Educational Resources Information Center
Veletsianos, George; Beth, Bradley; Lin, Calvin; Russell, Gregory
2016-01-01
"Thriving in Our Digital World" is a technology-enhanced dual enrollment course introducing high school students to computer science through project- and problem-based learning. This article describes the evolution of the course and five lessons learned during the design, development, implementation, and iteration of the course from its…
Novoselov, V P; Fedorov, S A
1999-01-01
UNISCAN scanner with PC was used at department of medical criminology and at the histological department of the Novosibirsk Regional Bureau of Forensic Medical Expert Evaluations. The quality of images obtained by computers and digital photography is not inferior to that of traditional photographs.
Academic Achievement Enhanced by Personal Digital Assistant Use
ERIC Educational Resources Information Center
Bick, Alexander
2005-01-01
Research during the past decade suggests that integrating computing technology in general, and mobile computers in particular, into the educational environment has positive effects. This is the first long-term study of high school Personal Digital Assistant use. It involved three-parts, 146 students during four years. Part one found that PDA use…
Digital-Computer Processing of Graphical Data. Final Report.
ERIC Educational Resources Information Center
Freeman, Herbert
The final report of a two-year study concerned with the digital-computer processing of graphical data. Five separate investigations carried out under this study are described briefly, and a detailed bibliography, complete with abstracts, is included in which are listed the technical papers and reports published during the period of this program.…
NASA Technical Reports Server (NTRS)
Fegley, K. A.; Hayden, J. H.; Rehmann, D. W.
1974-01-01
The feasibility of formulating a methodology for the modeling and analysis of aerospace electrical power processing systems is investigated. It is shown that a digital computer may be used in an interactive mode for the design, modeling, analysis, and comparison of power processing systems.
Phantom feet on digital radionuclide images and other scary computer tales
DOE Office of Scientific and Technical Information (OSTI.GOV)
Freitas, J.E.; Dworkin, H.J.; Dees, S.M.
1989-09-01
Malfunction of a computer-assisted digital gamma camera is reported. Despite what appeared to be adequate acceptance testing, an error in the system gave rise to switching of images and identification text. A suggestion is made for using a hot marker, which would avoid the potential error of misinterpretation of patient images.
What Is A Picture Archiving And Communication System (PACS)?
NASA Astrophysics Data System (ADS)
Marceau, Carla
1982-01-01
A PACS is a digital system for acquiring, storing, moving and displaying picture or image information. It is an alternative to film jackets that has been made possible by recent breakthroughs in computer technology: telecommunications, local area nets and optical disks. The fundamental concept of the digital representation of image information is introduced. It is shown that freeing images from a material representation on film or paper leads to a dramatic increase in flexibility in our use of the images. The ultimate goal of a medical PACS system is a radiology department without film jackets. The inherent nature of digital images and the power of the computer allow instant free "copies" of images to be made and thrown away. These copies can be transmitted to distant sites in seconds, without the "original" ever leaving the archives of the radiology department. The result is a radiology department with much freer access to patient images and greater protection against lost or misplaced image information. Finally, images in digital form can be treated as data for the computer in image processing, which includes enhancement, reconstruction and even computer-aided analysis.
NASA Technical Reports Server (NTRS)
Heffley, R. K.; Jewell, W. F.; Whitbeck, R. F.; Schulman, T. M.
1980-01-01
The effects of spurious delays in real time digital computing systems are examined. Various sources of spurious delays are defined and analyzed using an extant simulator system as an example. A specific analysis procedure is set forth and four cases are viewed in terms of their time and frequency domain characteristics. Numerical solutions are obtained for three single rate one- and two-computer examples, and the analysis problem is formulated for a two-rate, two-computer example.
Dastane, A; Vaidyanathan, T K; Vaidyanathan, J; Mehra, R; Hesby, R
1996-01-01
It is necessary to visualize and reconstruct tissue anatomic surfaces accurately for a variety of oral rehabilitation applications such as surface wear characterization and automated fabrication of dental restorations, accuracy of reproduction of impression and die materials, etc. In this investigation, a 3-D digitization and computer-graphic system was developed for surface characterization. The hardware consists of a profiler assembly for digitization in an MTS biomechanical test system with an artificial mouth, an IBM PS/2 computer model 70 for data processing and a Hewlett-Packard laser printer for hardcopy outputs. The software used includes a commercially available Surfer 3-D graphics package, a public domain data-fitting alignment software and an inhouse Pascal program for intercommunication plus some other limited tasks. Surfaces were digitized before and after rotation by angular displacement, the digital data were interpolated by Surfer to provide a data grid and the surfaces were computer graphically reconstructed: Misaligned surfaces were aligned by the data-fitting alignment software under different choices of parameters. The effect of different interpolation parameters (e.g. grid size, method of interpolation) and extent of rotation on the alignment accuracy was determined. The results indicate that improved alignment accuracy results from optimization of interpolation parameters and minimization of the initial misorientation between the digitized surfaces. The method provides important advantages for surface reconstruction and visualization, such as overlay of sequentially generated surfaces and accurate alignment of pairs of surfaces with small misalignment.
Pearson, Adam M; Spratt, Kevin F; Genuario, James; McGough, William; Kosman, Katherine; Lurie, Jon; Sengupta, Dilip K
2011-04-01
Comparison of intra- and interobserver reliability of digitized manual and computer-assisted intervertebral motion measurements and classification of "instability." To determine if computer-assisted measurement of lumbar intervertebral motion on flexion-extension radiographs improves reliability compared with digitized manual measurements. Many studies have questioned the reliability of manual intervertebral measurements, although few have compared the reliability of computer-assisted and manual measurements on lumbar flexion-extension radiographs. Intervertebral rotation, anterior-posterior (AP) translation, and change in anterior and posterior disc height were measured with a digitized manual technique by three physicians and by three other observers using computer-assisted quantitative motion analysis (QMA) software. Each observer measured 30 sets of digital flexion-extension radiographs (L1-S1) twice. Shrout-Fleiss intraclass correlation coefficients for intra- and interobserver reliabilities were computed. The stability of each level was also classified (instability defined as >4 mm AP translation or 10° rotation), and the intra- and interobserver reliabilities of the two methods were compared using adjusted percent agreement (APA). Intraobserver reliability intraclass correlation coefficients were substantially higher for the QMA technique THAN the digitized manual technique across all measurements: rotation 0.997 versus 0.870, AP translation 0.959 versus 0.557, change in anterior disc height 0.962 versus 0.770, and change in posterior disc height 0.951 versus 0.283. The same pattern was observed for interobserver reliability (rotation 0.962 vs. 0.693, AP translation 0.862 vs. 0.151, change in anterior disc height 0.862 vs. 0.373, and change in posterior disc height 0.730 vs. 0.300). The QMA technique was also more reliable for the classification of "instability." Intraobserver APAs ranged from 87 to 97% for QMA versus 60% to 73% for digitized manual measurements, while interobserver APAs ranged from 91% to 96% for QMA versus 57% to 63% for digitized manual measurements. The use of QMA software substantially improved the reliability of lumbar intervertebral measurements and the classification of instability based on flexion-extension radiographs.
Evolution of synchronization and desynchronization in digital organisms.
Knoester, David B; McKinley, Philip K
2011-01-01
We present a study in the evolution of temporal behavior, specifically synchronization and desynchronization, through digital evolution and group selection. In digital evolution, a population of self-replicating computer programs exists in a user-defined computational environment and is subject to instruction-level mutations and natural selection. Group selection links the survival of the individual to the survival of its group, thus encouraging cooperation. Previous approaches to engineering synchronization and desynchronization algorithms have taken inspiration from nature: In the well-known firefly model, the only form of communication between agents is in the form of flash messages among neighbors. Here we demonstrate that populations of digital organisms, provided with a similar mechanism and minimal information about their environment, are capable of evolving algorithms for synchronization and desynchronization, and that the evolved behaviors are robust to message loss. We further describe how the evolved behavior for synchronization mimics that of the well-known Ermentrout model for firefly synchronization in biology. In addition to discovering self-organizing behaviors for distributed computing systems, this result indicates that digital evolution may be used to further our understanding of synchronization in biology.
Techtalk: Cloud Computing and Developmental Education
ERIC Educational Resources Information Center
Holschuh, Douglas R.; Caverly, David C.
2010-01-01
Techtalk in Volume 33 has been addressing the digital divide in technology, first through the use of mobile phones and then through the development of digital literacies with digital storytelling. This third and final column in the series looks at bridging both the hardware/software divide and the digital literacies divide through the educational…
Digital Photography and Its Impact on Instruction.
ERIC Educational Resources Information Center
Lantz, Chris
Today the chemical processing of film is being replaced by a virtual digital darkroom. Digital image storage makes new levels of consistency possible because its nature is less volatile and more mutable than traditional photography. The potential of digital imaging is great, but issues of disk storage, computer speed, camera sensor resolution,…
Using Digital Classrooms to Conduct 4-H Club Meetings
ERIC Educational Resources Information Center
West, Patricia; Fuhrman, Nicholas E.; Morgan, A. Christian; Duncan, Dennis W.
2012-01-01
Using computer technology and digital classrooms to conduct 4-H Club meetings is an efficient way to continue delivering quality 4-H programming during times of limited resources and staff. Nineteen Junior and Senior 4-H'ers participated in seven digital classroom workshops using the Wimba Classroom application. These digital classroom sessions…
New Integrated Video and Graphics Technology: Digital Video Interactive.
ERIC Educational Resources Information Center
Optical Information Systems, 1987
1987-01-01
Describes digital video interactive (DVI), a new technology which combines the interactivity of the graphics capabilities in personal computers with the realism of high-quality motion video and multitrack audio in an all-digital integrated system. (MES)
Digital flight control research
NASA Technical Reports Server (NTRS)
Potter, J. E.; Stern, R. G.; Smith, T. B.; Sinha, P.
1974-01-01
The results of studies which were undertaken to contribute to the design of digital flight control systems, particularly for transport aircraft are presented. In addition to the overall design considerations for a digital flight control system, the following topics are discussed in detail: (1) aircraft attitude reference system design, (2) the digital computer configuration, (3) the design of a typical digital autopilot for transport aircraft, and (4) a hybrid flight simulator.
Digital multicolor printing: state of the art and future challenges
NASA Astrophysics Data System (ADS)
Kipphan, Helmut
1995-04-01
During the last 5 years, digital techniques have become extremely important in the graphic arts industry. All sections in the production flow for producing multicolor printed products - prepress, printing and postpress - are influenced by digitalization, in an evolutionary and revolutionary way. New equipment and network techniques bring all the sections closer together. The focus is put on high-quality multicolor printing, together with high productivity. Conventional offset printing technology is compared with the leading nonimpact printing technologies. Computer to press is contrasted with computer to print techniques. The newest available digital multicolor presses are described - the direct imaging offset printing press from HEIDELBERG with new laser imaging technique as well as the INDIGO and XEIKON presses based on electrophotography. Regarding technical specifications, economic calculations and print quality, it is worked out that each technique has its own market segments. An outlook is given for future computer to press techniques and the potential of nonimpact printing technologies for advanced high-speed multicolor computer to print equipment. Synergy effects from the NIP-technologies to the conventional printing technologies and vice versa are possible for building up innovative new products, for example hybrid printing systems. It is also shown that there is potential for improving the print quality, based on special screening algorithms, and a higher number of grey levels per pixel by using NIP-technologies. As an intermediate step in digitalization of the production flow, but also as an economical solution computer to plate equipment is described. By producing printed products totally in a digital way, digital color proofing as well as color management systems are needed. The newest high-tech equipment using NIP-technologies for producing proofs is explained. All in all it is shown that the state of the art in digital multicolor printing has reached a very high level in technology, productivity and quality, but that there is still space for improvements and innovations. Manufacturers of equipment and producers of printed products can take part in a successful evolution-changes, chances and challenges must be recognized and considered for future orientated activities and investments.
Documentation of surgical specimens using digital video technology.
Melín-Aldana, Héctor; Carter, Barbara; Sciortino, Debra
2006-09-01
Digital technology is commonly used for documentation of specimens in anatomic pathology and has been mainly limited to still photographs. Technologic innovations, such as digital video, provide additional, in some cases better, options for documentation. To demonstrate the applicability of digital video to the documentation of surgical specimens. A Canon Elura MC40 digital camcorder was used, and the unedited movies were transferred to a Macintosh PowerBook G4 computer. Both the camcorder and specimens were hand-held during filming. The movies were edited using the software iMovie. Annotations and histologic photographs may be easily incorporated into movies when editing, if desired. The finished movies are best viewed in computers which contain the free program QuickTime Player. Movies may also be incorporated onto DVDs, for viewing in standard DVD players or appropriately equipped computers. The final movies are on average 2 minutes in duration, with a file size between 2 and 400 megabytes, depending on the intended use. Because of file size, distribution is more practical via CD or DVD, but movies may be compressed for distribution through the Internet (e-mail, Web sites) or through internal hospital networks. Digital video is a practical, easy, and affordable methodology for specimen documentation, permitting a better 3-dimensional understanding of the specimens. Discussions with colleagues, student education, presentation at conferences, and other educational activities can be enhanced with the implementation of digital video technology.
Active flutter suppression using optical output feedback digital controllers
NASA Technical Reports Server (NTRS)
1982-01-01
A method for synthesizing digital active flutter suppression controllers using the concept of optimal output feedback is presented. A convergent algorithm is employed to determine constrained control law parameters that minimize an infinite time discrete quadratic performance index. Low order compensator dynamics are included in the control law and the compensator parameters are computed along with the output feedback gain as part of the optimization process. An input noise adjustment procedure is used to improve the stability margins of the digital active flutter controller. Sample rate variation, prefilter pole variation, control structure variation and gain scheduling are discussed. A digital control law which accommodates computation delay can stabilize the wing with reasonable rms performance and adequate stability margins.
NASA Astrophysics Data System (ADS)
Chang, S. S. L.
State of the art technology in circuits, fields, and electronics is discussed. The principles and applications of these technologies to industry, digital processing, microwave semiconductors, and computer-aided design are explained. Important concepts and methodologies in mathematics and physics are reviewed, and basic engineering sciences and associated design methods are dealt with, including: circuit theory and the design of magnetic circuits and active filter synthesis; digital signal processing, including FIR and IIR digital filter design; transmission lines, electromagnetic wave propagation and surface acoustic wave devices. Also considered are: electronics technologies, including power electronics, microwave semiconductors, GaAs devices, and magnetic bubble memories; digital circuits and logic design.
The thinking of Cloud computing in the digital construction of the oil companies
NASA Astrophysics Data System (ADS)
CaoLei, Qizhilin; Dengsheng, Lei
In order to speed up digital construction of the oil companies and enhance productivity and decision-support capabilities while avoiding the disadvantages from the waste of the original process of building digital and duplication of development and input. This paper presents a cloud-based models for the build in the digital construction of the oil companies that National oil companies though the private network will join the cloud data of the oil companies and service center equipment integrated into a whole cloud system, then according to the needs of various departments to prepare their own virtual service center, which can provide a strong service industry and computing power for the Oil companies.
Texture functions in image analysis: A computationally efficient solution
NASA Technical Reports Server (NTRS)
Cox, S. C.; Rose, J. F.
1983-01-01
A computationally efficient means for calculating texture measurements from digital images by use of the co-occurrence technique is presented. The calculation of the statistical descriptors of image texture and a solution that circumvents the need for calculating and storing a co-occurrence matrix are discussed. The results show that existing efficient algorithms for calculating sums, sums of squares, and cross products can be used to compute complex co-occurrence relationships directly from the digital image input.
NASA Technical Reports Server (NTRS)
Rushby, John
1991-01-01
The formal specification and mechanically checked verification for a model of fault-masking and transient-recovery among the replicated computers of digital flight-control systems are presented. The verification establishes, subject to certain carefully stated assumptions, that faults among the component computers are masked so that commands sent to the actuators are the same as those that would be sent by a single computer that suffers no failures.
MAGIC Computer Simulation. Volume 1: User Manual
1970-07-01
vulnerability and MAGIC programs. A three-digit code is assigned to each component of the target, such as armor, gun tube; and a two-digit code is assigned to...A review of the subject Magic Computer Simulation User and Analyst Manuals has been conducted based upon a request received from the US Army...1970 4. TITLE AND SUBTITLE MAGIC Computer Simulation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT
Synthetic Analog and Digital Circuits for Cellular Computation and Memory
Purcell, Oliver; Lu, Timothy K.
2014-01-01
Biological computation is a major area of focus in synthetic biology because it has the potential to enable a wide range of applications. Synthetic biologists have applied engineering concepts to biological systems in order to construct progressively more complex gene circuits capable of processing information in living cells. Here, we review the current state of computational genetic circuits and describe artificial gene circuits that perform digital and analog computation. We then discuss recent progress in designing gene circuits that exhibit memory, and how memory and computation have been integrated to yield more complex systems that can both process and record information. Finally, we suggest new directions for engineering biological circuits capable of computation. PMID:24794536
Emulating a million machines to investigate botnets.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rudish, Donald W.
2010-06-01
Researchers at Sandia National Laboratories in Livermore, California are creating what is in effect a vast digital petridish able to hold one million operating systems at once in an effort to study the behavior of rogue programs known as botnets. Botnets are used extensively by malicious computer hackers to steal computing power fron Internet-connected computers. The hackers harness the stolen resources into a scattered but powerful computer that can be used to send spam, execute phishing, scams or steal digital information. These remote-controlled 'distributed computers' are difficult to observe and track. Botnets may take over parts of tens of thousandsmore » or in some cases even millions of computers, making them among the world's most powerful computers for some applications.« less
ERIC Educational Resources Information Center
McConnell, Terry
2004-01-01
Monica Adams, head librarian at Robinson Secondary in Fairfax country, Virginia, states that librarians should have the technical knowledge to support projects related to digital video editing. The process of digital video editing and the cables, storage issues and the computer system with software is described.
Hybrid acousto-optic and digital equalization for microwave digital radio channels
NASA Astrophysics Data System (ADS)
Anderson, C. S.; Vanderlugt, A.
1990-11-01
Digital radio transmission systems use complex modulation schemes that require powerful signal-processing techniques to correct channel distortions and to minimize BERs. This paper proposes combining the computation power of acoustooptic processing and the accuracy of digital processing to produce a hybrid channel equalizer that exceeds the performance of digital equalization alone. Analysis shows that a hybrid equalizer for 256-level quadrature amplitude modulation (QAM) performs better than a digital equalizer for 64-level QAM.
Color camera computed tomography imaging spectrometer for improved spatial-spectral image accuracy
NASA Technical Reports Server (NTRS)
Wilson, Daniel W. (Inventor); Bearman, Gregory H. (Inventor); Johnson, William R. (Inventor)
2011-01-01
Computed tomography imaging spectrometers ("CTIS"s) having color focal plane array detectors are provided. The color FPA detector may comprise a digital color camera including a digital image sensor, such as a Foveon X3.RTM. digital image sensor or a Bayer color filter mosaic. In another embodiment, the CTIS includes a pattern imposed either directly on the object scene being imaged or at the field stop aperture. The use of a color FPA detector and the pattern improves the accuracy of the captured spatial and spectral information.
NASA Technical Reports Server (NTRS)
Adams, J. R.; Hawley, S. W.; Peterson, G. R.; Salinger, S. S.; Workman, R. A.
1971-01-01
A hardware and software specification covering requirements for the computer enhancement of structural weld radiographs was considered. Three scanning systems were used to digitize more than 15 weld radiographs. The performance of these systems was evaluated by determining modulation transfer functions and noise characteristics. Enhancement techniques were developed and applied to the digitized radiographs. The scanning parameters of spot size and spacing and film density were studied to optimize the information content of the digital representation of the image.
Visual Form Perception Can Be a Cognitive Correlate of Lower Level Math Categories for Teenagers
Cui, Jiaxin; Zhang, Yiyun; Cheng, Dazhi; Li, Dawei; Zhou, Xinlin
2017-01-01
Numerous studies have assessed the cognitive correlates of performance in mathematics, but little research has been conducted to systematically examine the relations between visual perception as the starting point of visuospatial processing and typical mathematical performance. In the current study, we recruited 223 seventh graders to perform a visual form perception task (figure matching), numerosity comparison, digit comparison, exact computation, approximate computation, and curriculum-based mathematical achievement tests. Results showed that, after controlling for gender, age, and five general cognitive processes (choice reaction time, visual tracing, mental rotation, spatial working memory, and non-verbal matrices reasoning), visual form perception had unique contributions to numerosity comparison, digit comparison, and exact computation, but had no significant relation with approximate computation or curriculum-based mathematical achievement. These results suggest that visual form perception is an important independent cognitive correlate of lower level math categories, including the approximate number system, digit comparison, and exact computation. PMID:28824513
The iPad and EFL Digital Literacy
NASA Astrophysics Data System (ADS)
Meurant, Robert C.
In future, the uses of English by non-native speakers will predominantly be online, using English language digital resources, and in computer-mediated communication with other non-native speakers of English. Thus for Korea to be competitive in the global economy, its EFL should develop L2 Digital Literacy in English. With its fast Internet connections, Korea is the most wired nation on Earth; but ICT facilities in educational institutions need reorganization. Opportunities for computer-mediated second language learning need to be increased, providing multimedia-capable, mobile web solutions that put the Internet into the hands of all students and teachers. Wi-Fi networked campuses allow any campus space to act as a wireless classroom. Every classroom should have a teacher's computer console. All students should be provided with adequate computing facilities, that are available anywhere, anytime. Ubiquitous computing has now become feasible by providing every student on enrollment with a tablet: a Wi-Fi+3G enabled Apple iPad.
NASA Technical Reports Server (NTRS)
Smith, Dean Lance
1993-01-01
Work continued on the design of two IBM PC/AT compatible computer interface boards. The boards will permit digital data to be transmitted over a composite video channel from the Orbiter. One board combines data with a composite video signal. The other board strips the data from the video signal.
Math modeling and computer mechanization for real time simulation of rotary-wing aircraft
NASA Technical Reports Server (NTRS)
Howe, R. M.
1979-01-01
Mathematical modeling and computer mechanization for real time simulation of rotary wing aircraft is discussed. Error analysis in the digital simulation of dynamic systems, such as rotary wing aircraft is described. The method for digital simulation of nonlinearities with discontinuities, such as exist in typical flight control systems and rotor blade hinges, is discussed.
Leveraging Learning for Generation I [and] The Haves and Have Nots of the Digital Divide.
ERIC Educational Resources Information Center
Angulo, Martha; Feldman, Sandra
2001-01-01
The Internet's effects are spreading. Schools are purchasing computer programs, assisted by state, federal, and corporate grants. K-12 schools spent nearly $7 billion on instructional technology in 2000. The digital divide is narrowing; Generation I kids have greater computer access at home and at school. In a sidebar, Sandra Feldman urges…
ERIC Educational Resources Information Center
Mostmans, Lien; Vleugels, Chris; Bannier, Stijn
2012-01-01
Young people are often referred to as digital natives, who are familiar with digital technologies such as computers, the Internet and mobile phones for communication, entertainment and accessing information. As a result scholars have called for an educational approach that bypasses the traditional unidirectional lecture teaching style, and applies…
ERIC Educational Resources Information Center
Mattoon, Cassandra; Bates, Alan; Shifflet, Rena; Latham, Nancy; Ennis, Sarah
2015-01-01
The authors investigated benefits of digital technology compared with traditional manipulatives in relation to preschoolers' development and learning of computational skills. The sample consisted of twenty four 4-and 5-year old children who attended a half-day prekindergarten program five times a week in a university laboratory school in the…
A Digital Simulation Program for Health Science Students to Follow Drug Levels in the Body
ERIC Educational Resources Information Center
Stavchansky, Salomon; And Others
1977-01-01
The Rayetheon Scientific Simulation Language (RSSL) program, an easily-used simulation on the CDC/6600 computer at the University of Texas at Austin, offers a simple method of solving differential equations on a digital computer. It is used by undergraduate biopharmaceutics-pharmacokinetics students and graduate students in all areas. (Author/LBH)
Computer Problems Can Infuriate Even the Most Tech Savvy
ERIC Educational Resources Information Center
Goldsborough, Reid
2004-01-01
Which high-tech products give you the most grief? Surprisingly, more people singled out TiVo and replay digital recording systems than personal computers, according to a recent survey by Best Buy. Nine percent of people said they found these TV devices difficult to use. The same percentage found PDAs (personal digital assistants) difficult. Only 2…
Computer Forensics: Is It the Next Hot IT Subject?
ERIC Educational Resources Information Center
Williams, Victor G.; Revels, Ken
2006-01-01
Digital Forensics is not just the recovery of data or information from computer systems and their networks. It is not a procedure that can be accomplished by software alone, and most important, it is not something that can be accomplished by other than a trained IT forensic professional. Digital Forensics is an emerging science and was developed…
Digital data collection in forest dynamics plots
Faith Inman-Narahari; Christian Giardina; Rebecca Ostertag; Susan Cordell; Lawren Sack
2010-01-01
Summary 1. Computers are widely used in all aspects of research but their application to in-field data collection for forest plots has rarely been evaluated. 2. We developed digital data collection methods using ESRI mapping software and ruggedized field computers to map and measure ~30 000 trees in two 4-ha forest dynamics plots in wet and dry...
NASA Technical Reports Server (NTRS)
Ratner, R. S.; Shapiro, E. B.; Zeidler, H. M.; Wahlstrom, S. E.; Clark, C. B.; Goldberg, J.
1973-01-01
This final report summarizes the work on the design of a fault tolerant digital computer for aircraft. Volume 2 is composed of two parts. Part 1 is concerned with the computational requirements associated with an advanced commercial aircraft. Part 2 reviews the technology that will be available for the implementation of the computer in the 1975-1985 period. With regard to the computation task 26 computations have been categorized according to computational load, memory requirements, criticality, permitted down-time, and the need to save data in order to effect a roll-back. The technology part stresses the impact of large scale integration (LSI) on the realization of logic and memory. Also considered was module interconnection possibilities so as to minimize fault propagation.
Computational Modeling and Treatment Identification in the Myelodysplastic Syndromes.
Drusbosky, Leylah M; Cogle, Christopher R
2017-10-01
This review discusses the need for computational modeling in myelodysplastic syndromes (MDS) and early test results. As our evolving understanding of MDS reveals a molecularly complicated disease, the need for sophisticated computer analytics is required to keep track of the number and complex interplay among the molecular abnormalities. Computational modeling and digital drug simulations using whole exome sequencing data input have produced early results showing high accuracy in predicting treatment response to standard of care drugs. Furthermore, the computational MDS models serve as clinically relevant MDS cell lines for pre-clinical assays of investigational agents. MDS is an ideal disease for computational modeling and digital drug simulations. Current research is focused on establishing the prediction value of computational modeling. Future research will test the clinical advantage of computer-informed therapy in MDS.
NASA Astrophysics Data System (ADS)
Divayana, D. G. H.; Adiarta, A.; Abadi, I. B. G. S.
2018-01-01
The aim of this research was to create initial design of CSE-UCLA evaluation model modified with Weighted Product in evaluating digital library service at Computer College in Bali. The method used in this research was developmental research method and developed by Borg and Gall model design. The results obtained from the research that conducted earlier this month was a rough sketch of Weighted Product based CSE-UCLA evaluation model that the design had been able to provide a general overview of the stages of weighted product based CSE-UCLA evaluation model used in order to optimize the digital library services at the Computer Colleges in Bali.
Design of a fault tolerant airborne digital computer. Volume 1: Architecture
NASA Technical Reports Server (NTRS)
Wensley, J. H.; Levitt, K. N.; Green, M. W.; Goldberg, J.; Neumann, P. G.
1973-01-01
This volume is concerned with the architecture of a fault tolerant digital computer for an advanced commercial aircraft. All of the computations of the aircraft, including those presently carried out by analogue techniques, are to be carried out in this digital computer. Among the important qualities of the computer are the following: (1) The capacity is to be matched to the aircraft environment. (2) The reliability is to be selectively matched to the criticality and deadline requirements of each of the computations. (3) The system is to be readily expandable. contractible, and (4) The design is to appropriate to post 1975 technology. Three candidate architectures are discussed and assessed in terms of the above qualities. Of the three candidates, a newly conceived architecture, Software Implemented Fault Tolerance (SIFT), provides the best match to the above qualities. In addition SIFT is particularly simple and believable. The other candidates, Bus Checker System (BUCS), also newly conceived in this project, and the Hopkins multiprocessor are potentially more efficient than SIFT in the use of redundancy, but otherwise are not as attractive.
Performance evaluation of digital phase-locked loops for advanced deep space transponders
NASA Technical Reports Server (NTRS)
Nguyen, T. M.; Hinedi, S. M.; Yeh, H.-G.; Kyriacou, C.
1994-01-01
The performances of the digital phase-locked loops (DPLL's) for the advanced deep-space transponders (ADT's) are investigated. DPLL's considered in this article are derived from the analog phase-locked loop, which is currently employed by the NASA standard deep space transponder, using S-domain to Z-domain mapping techniques. Three mappings are used to develop digital approximations of the standard deep space analog phase-locked loop, namely the bilinear transformation (BT), impulse invariant transformation (IIT), and step invariant transformation (SIT) techniques. The performance in terms of the closed loop phase and magnitude responses, carrier tracking jitter, and response of the loop to the phase offset (the difference between in incoming phase and reference phase) is evaluated for each digital approximation. Theoretical results of the carrier tracking jitter for command-on and command-off cases are then validated by computer simulation. Both theoretical and computer simulation results show that at high sampling frequency, the DPLL's approximated by all three transformations have the same tracking jitter. However, at low sampling frequency, the digital approximation using BT outperforms the others. The minimum sampling frequency for adequate tracking performance is determined for each digital approximation of the analog loop. In addition, computer simulation shows that the DPLL developed by BT provides faster response to the phase offset than IIT and SIT.
Vaccaro, Calogero; Busetto, Roberto; Bernardini, Daniele; Anselmi, Carlo; Zotti, Alessandro
2012-03-01
To evaluate the precision and accuracy of assessing bone mineral density (BMD) by use of mean gray value (MGV) on digitalized and digital images of conventional and digital radiographs, respectively, of ex vivo bovine and equine bone specimens in relation to the gold-standard technique of dual-energy x-ray absorptiometry (DEXA). Left and right metatarsal bones from 11 beef cattle and right femurs from 2 horses. Bovine specimens were imaged by use of conventional radiography, whereas equine specimens were imaged by use of computed radiography (digital radiography). Each specimen was subsequently scanned by use of the same DEXA equipment. The BMD values resulting from each DEXA scan were paired with the MGVs obtained by use of software on the corresponding digitalized or digital radiographic image. The MGV analysis of digitalized and digital x-ray images was a precise (coefficient of variation, 0.1 and 0.09, respectively) and highly accurate method for assessing BMD, compared with DEXA (correlation coefficient, 0.910 and 0.937 for conventional and digital radiography, respectively). The high correlation between MGV and BMD indicated that MGV analysis may be a reliable alternative to DEXA in assessing radiographic bone density. This may provide a new, inexpensive, and readily available estimate of BMD.
Digital microscopy. Bringing new technology into focus.
2010-06-01
Digital microscopy enables the scanning of microscope slides so that they can be viewed, analyzed, and archived on a computer. While the technology is not yet widely accepted by pathologists, a switch to digital microscopy systems seems to be inevitable in the near future.
Digital Image Access & Retrieval.
ERIC Educational Resources Information Center
Heidorn, P. Bryan, Ed.; Sandore, Beth, Ed.
Recent technological advances in computing and digital imaging technology have had immediate and permanent consequences for visual resource collections. Libraries are involved in organizing and managing large visual resource collections. The central challenges in working with digital image collections mirror those that libraries have sought to…
Digital systems design language. Design synthesis of digital systems
NASA Technical Reports Server (NTRS)
Shiva, S. G.
1979-01-01
The Digital Systems Design Language (DDL) is implemented on the SEL-32 computer systems. The details of the language, translator and simulator programs are included. Several example descriptions and a tutorial on hardware description languages are provided, to guide the user.
High-End Computing Challenges in Aerospace Design and Engineering
NASA Technical Reports Server (NTRS)
Bailey, F. Ronald
2004-01-01
High-End Computing (HEC) has had significant impact on aerospace design and engineering and is poised to make even more in the future. In this paper we describe four aerospace design and engineering challenges: Digital Flight, Launch Simulation, Rocket Fuel System and Digital Astronaut. The paper discusses modeling capabilities needed for each challenge and presents projections of future near and far-term HEC computing requirements. NASA's HEC Project Columbia is described and programming strategies presented that are necessary to achieve high real performance.
NASA Technical Reports Server (NTRS)
Ohri, A. K.; Owen, H. A.; Wilson, T. G.; Rodriguez, G. E.
1974-01-01
The simulation of converter-controller combinations by means of a flexible digital computer program which produces output to a graphic display is discussed. The procedure is an alternative to mathematical analysis of converter systems. The types of computer programming involved in the simulation are described. Schematic diagrams, state equations, and output equations are displayed for four basic forms of inductor-energy-storage dc to dc converters. Mathematical models are developed to show the relationship of the parameters.
A serial digital data communications device. [for real time flight simulation
NASA Technical Reports Server (NTRS)
Fetter, J. L.
1977-01-01
A general purpose computer peripheral device which is used to provide a full-duplex, serial, digital data transmission link between a Xerox Sigma computer and a wide variety of external equipment, including computers, terminals, and special purpose devices is reported. The interface has an extensive set of user defined options to assist the user in establishing the necessary data links. This report describes those options and other features of the serial communications interface and its performance by discussing its application to a particular problem.
Digital optical interconnects for photonic computing
NASA Astrophysics Data System (ADS)
Guilfoyle, Peter S.; Stone, Richard V.; Zeise, Frederick F.
1994-05-01
A 32-bit digital optical computer (DOC II) has been implemented in hardware utilizing 8,192 free-space optical interconnects. The architecture exploits parallel interconnect technology by implementing microcode at the primitive level. A burst mode of 0.8192 X 1012 binary operations per sec has been reliably demonstrated. The prototype has been successful in demonstrating general purpose computation. In addition to emulating the RISC instruction set within the UNIX operating environment, relational database text search operations have been implemented on DOC II.
Yu, Q
2018-04-09
Computer aided design and computer aided manufacture (CAD/CAM) technology is a kind of oral digital system which is applied to clinical diagnosis and treatment. It overturns the traditional pattern, and provides a solution to restore defect tooth quickly and efficiently. In this paper we mainly discuss the clinical skills of chair-side CAD/CAM system, including tooth preparation, digital impression, the three-dimensional design of prosthesis, numerical control machining, clinical bonding and so on, and review the outcomes of several common kinds of materials at the same time.
NASA Technical Reports Server (NTRS)
Hayden, W. L.; Robinson, L. H.
1972-01-01
Spectral analyses of angle-modulated communication systems is studied by: (1) performing a literature survey of candidate power spectrum computational techniques, determining the computational requirements, and formulating a mathematical model satisfying these requirements; (2) implementing the model on UNIVAC 1230 digital computer as the Spectral Analysis Program (SAP); and (3) developing the hardware specifications for a data acquisition system which will acquire an input modulating signal for SAP. The SAP computational technique uses extended fast Fourier transform and represents a generalized approach for simple and complex modulating signals.
Grajski, Kamil A.
2016-01-01
Mechanisms underlying the emergence and plasticity of representational discontinuities in the mammalian primary somatosensory cortical representation of the hand are investigated in a computational model. The model consists of an input lattice organized as a three-digit hand forward-connected to a lattice of cortical columns each of which contains a paired excitatory and inhibitory cell. Excitatory and inhibitory synaptic plasticity of feedforward and lateral connection weights is implemented as a simple covariance rule and competitive normalization. Receptive field properties are computed independently for excitatory and inhibitory cells and compared within and across columns. Within digit representational zones intracolumnar excitatory and inhibitory receptive field extents are concentric, single-digit, small, and unimodal. Exclusively in representational boundary-adjacent zones, intracolumnar excitatory and inhibitory receptive field properties diverge: excitatory cell receptive fields are single-digit, small, and unimodal; and the paired inhibitory cell receptive fields are bimodal, double-digit, and large. In simulated syndactyly (webbed fingers), boundary-adjacent intracolumnar receptive field properties reorganize to within-representation type; divergent properties are reacquired following syndactyly release. This study generates testable hypotheses for assessment of cortical laminar-dependent receptive field properties and plasticity within and between cortical representational zones. For computational studies, present results suggest that concurrent excitatory and inhibitory plasticity may underlie novel emergent properties. PMID:27504086
Digital signal conditioning for flight test instrumentation
NASA Technical Reports Server (NTRS)
Bever, Glenn A.
1991-01-01
An introduction to digital measurement processes on aircraft is provided. Flight test instrumentation systems are rapidly evolving from analog-intensive to digital intensive systems, including the use of onboard digital computers. The topics include measurements that are digital in origin, as well as sampling, encoding, transmitting, and storing data. Particular emphasis is placed on modern avionic data bus architectures and what to be aware of when extracting data from them. Examples of data extraction techniques are given. Tradeoffs between digital logic families, trends in digital development, and design testing techniques are discussed. An introduction to digital filtering is also covered.
Accuracy of five intraoral scanners compared to indirect digitalization.
Güth, Jan-Frederik; Runkel, Cornelius; Beuer, Florian; Stimmelmayr, Michael; Edelhoff, Daniel; Keul, Christine
2017-06-01
Direct and indirect digitalization offer two options for computer-aided design (CAD)/ computer-aided manufacturing (CAM)-generated restorations. The aim of this study was to evaluate the accuracy of different intraoral scanners and compare them to the process of indirect digitalization. A titanium testing model was directly digitized 12 times with each intraoral scanner: (1) CS 3500 (CS), (2) Zfx Intrascan (ZFX), (3) CEREC AC Bluecam (BLU), (4) CEREC AC Omnicam (OC) and (5) True Definition (TD). As control, 12 polyether impressions were taken and the referring plaster casts were digitized indirectly with the D-810 laboratory scanner (CON). The accuracy (trueness/precision) of the datasets was evaluated by an analysing software (Geomagic Qualify 12.1) using a "best fit alignment" of the datasets with a highly accurate reference dataset of the testing model, received from industrial computed tomography. Direct digitalization using the TD showed the significant highest overall "trueness", followed by CS. Both performed better than CON. BLU, ZFX and OC showed higher differences from the reference dataset than CON. Regarding the overall "precision", the CS 3500 intraoral scanner and the True Definition showed the best performance. CON, BLU and OC resulted in significantly higher precision than ZFX did. Within the limitations of this in vitro study, the accuracy of the ascertained datasets was dependent on the scanning system. The direct digitalization was not superior to indirect digitalization for all tested systems. Regarding the accuracy, all tested intraoral scanning technologies seem to be able to reproduce a single quadrant within clinical acceptable accuracy. However, differences were detected between the tested systems.
Local sharpening and subspace wavefront correction with predictive dynamic digital holography
NASA Astrophysics Data System (ADS)
Sulaiman, Sennan; Gibson, Steve
2017-09-01
Digital holography holds several advantages over conventional imaging and wavefront sensing, chief among these being significantly fewer and simpler optical components and the retrieval of complex field. Consequently, many imaging and sensing applications including microscopy and optical tweezing have turned to using digital holography. A significant obstacle for digital holography in real-time applications, such as wavefront sensing for high energy laser systems and high speed imaging for target racking, is the fact that digital holography is computationally intensive; it requires iterative virtual wavefront propagation and hill-climbing to optimize some sharpness criteria. It has been shown recently that minimum-variance wavefront prediction can be integrated with digital holography and image sharpening to reduce significantly large number of costly sharpening iterations required to achieve near-optimal wavefront correction. This paper demonstrates further gains in computational efficiency with localized sharpening in conjunction with predictive dynamic digital holography for real-time applications. The method optimizes sharpness of local regions in a detector plane by parallel independent wavefront correction on reduced-dimension subspaces of the complex field in a spectral plane.
3D Computer aided treatment planning in endodontics.
van der Meer, Wicher J; Vissink, Arjan; Ng, Yuan Ling; Gulabivala, Kishor
2016-02-01
Obliteration of the root canal system due to accelerated dentinogenesis and dystrophic calcification can challenge the achievement of root canal treatment goals. This paper describes the application of 3D digital mapping technology for predictable navigation of obliterated canal systems during root canal treatment to avoid iatrogenic damage of the root. Digital endodontic treatment planning for anterior teeth with severely obliterated root canal systems was accomplished with the aid of computer software, based on cone beam computer tomography (CBCT) scans and intra-oral scans of the dentition. On the basis of these scans, endodontic guides were created for the planned treatment through digital designing and rapid prototyping fabrication. The custom-made guides allowed for an uncomplicated and predictable canal location and management. The method of digital designing and rapid prototyping of endodontic guides allows for reliable and predictable location of root canals of teeth with calcifically metamorphosed root canal systems. The endodontic directional guide facilitates difficult endodontic treatments at little additional cost. Copyright © 2016. Published by Elsevier Ltd.
NASA Technical Reports Server (NTRS)
Cowings, Patricia S.; Naifeh, Karen; Thrasher, Chet
1988-01-01
This report contains the source code and documentation for a computer program used to process impedance cardiography data. The cardiodynamic measures derived from impedance cardiography are ventricular stroke column, cardiac output, cardiac index and Heather index. The program digitizes data collected from the Minnesota Impedance Cardiograph, Electrocardiography (ECG), and respiratory cycles and then stores these data on hard disk. It computes the cardiodynamic functions using interactive graphics and stores the means and standard deviations of each 15-sec data epoch on floppy disk. This software was designed on a Digital PRO380 microcomputer and used version 2.0 of P/OS, with (minimally) a 4-channel 16-bit analog/digital (A/D) converter. Applications software is written in FORTRAN 77, and uses Digital's Pro-Tool Kit Real Time Interface Library, CORE Graphic Library, and laboratory routines. Source code can be readily modified to accommodate alternative detection, A/D conversion and interactive graphics. The object code utilizing overlays and multitasking has a maximum of 50 Kbytes.
Compressed digital holography: from micro towards macro
NASA Astrophysics Data System (ADS)
Schretter, Colas; Bettens, Stijn; Blinder, David; Pesquet-Popescu, Béatrice; Cagnazzo, Marco; Dufaux, Frédéric; Schelkens, Peter
2016-09-01
signal processing methods from software-driven computer engineering and applied mathematics. The compressed sensing theory in particular established a practical framework for reconstructing the scene content using few linear combinations of complex measurements and a sparse prior for regularizing the solution. Compressed sensing found direct applications in digital holography for microscopy. Indeed, the wave propagation phenomenon in free space mixes in a natural way the spatial distribution of point sources from the 3-dimensional scene. As the 3-dimensional scene is mapped to a 2-dimensional hologram, the hologram samples form a compressed representation of the scene as well. This overview paper discusses contributions in the field of compressed digital holography at the micro scale. Then, an outreach on future extensions towards the real-size macro scale is discussed. Thanks to advances in sensor technologies, increasing computing power and the recent improvements in sparse digital signal processing, holographic modalities are on the verge of practical high-quality visualization at a macroscopic scale where much higher resolution holograms must be acquired and processed on the computer.
Digital Poetry: A Narrow Relation between Poetics and the Codes of the Computational Logic
NASA Astrophysics Data System (ADS)
Laurentiz, Silvia
The project "Percorrendo Escrituras" (Walking Through Writings Project) has been developed at ECA-USP Fine Arts Department. Summarizing, it intends to study different structures of digital information that share the same universe and are generators of a new aesthetics condition. The aim is to search which are the expressive possibilities of the computer among the algorithm functions and other of its specific properties. It is a practical, theoretical and interdisciplinary project where the study of programming evolutionary language, logic and mathematics take us to poetic experimentations. The focus of this research is the digital poetry, and it comes from poetics of permutation combinations and culminates with dynamic and complex systems, autonomous, multi-user and interactive, through agents generation derivations, filtration and emergent standards. This lecture will present artworks that use some mechanisms introduced by cybernetics and the notion of system in digital poetry that demonstrate the narrow relationship between poetics and the codes of computational logic.
Which Disc Player for Education? A Comparative Evaluation.
ERIC Educational Resources Information Center
Leveridge, Leo L.; Lyons, David S.
1983-01-01
Advantages and disadvantages of videodisc players using digital program dumps are discussed. Indicates that, although digital dumps on videodiscs can be used to deliver interactive audiovisual programs about as effectively as external computer programs, disadvantages greatly outweigh advantages. Thus, digital program dumps recorded on videodiscs…
A National Consideration of Digital Equity
ERIC Educational Resources Information Center
Davis, T.; Fuller, M.; Jackson, S.; Pittman, J.; Sweet, J.
2007-01-01
The National Center for Education Statistics (NCES) report, "Computer and Internet Use by Students in 2003" (NCES, 2006) reveals that the digital divide continues to exist, particularly along demographic and socioeconomic lines. Though an exact definition remains elusive, the term "digital divide" generally refers to the…
Improved stereo matching applied to digitization of greenhouse plants
NASA Astrophysics Data System (ADS)
Zhang, Peng; Xu, Lihong; Li, Dawei; Gu, Xiaomeng
2015-03-01
The digitization of greenhouse plants is an important aspect of digital agriculture. Its ultimate aim is to reconstruct a visible and interoperable virtual plant model on the computer by using state-of-the-art image process and computer graphics technologies. The most prominent difficulties of the digitization of greenhouse plants include how to acquire the three-dimensional shape data of greenhouse plants and how to carry out its realistic stereo reconstruction. Concerning these issues an effective method for the digitization of greenhouse plants is proposed by using a binocular stereo vision system in this paper. Stereo vision is a technique aiming at inferring depth information from two or more cameras; it consists of four parts: calibration of the cameras, stereo rectification, search of stereo correspondence and triangulation. Through the final triangulation procedure, the 3D point cloud of the plant can be achieved. The proposed stereo vision system can facilitate further segmentation of plant organs such as stems and leaves; moreover, it can provide reliable digital samples for the visualization of greenhouse tomato plants.
Reljin, Branimir; Milosević, Zorica; Stojić, Tomislav; Reljin, Irini
2009-01-01
Two methods for segmentation and visualization of microcalcifications in digital or digitized mammograms are described. First method is based on modern mathematical morphology, while the second one uses the multifractal approach. In the first method, by using an appropriate combination of some morphological operations, high local contrast enhancement, followed by significant suppression of background tissue, irrespective of its radiology density, is obtained. By iterative procedure, this method highly emphasizes only small bright details, possible microcalcifications. In a multifractal approach, from initial mammogram image, a corresponding multifractal "images" are created, from which a radiologist has a freedom to change the level of segmentation. An appropriate user friendly computer aided visualization (CAV) system with embedded two methods is realized. The interactive approach enables the physician to control the level and the quality of segmentation. Suggested methods were tested through mammograms from MIAS database as a gold standard, and from clinical praxis, using digitized films and digital images from full field digital mammograph.
Neural Computation and the Computational Theory of Cognition
ERIC Educational Resources Information Center
Piccinini, Gualtiero; Bahar, Sonya
2013-01-01
We begin by distinguishing computationalism from a number of other theses that are sometimes conflated with it. We also distinguish between several important kinds of computation: computation in a generic sense, digital computation, and analog computation. Then, we defend a weak version of computationalism--neural processes are computations in the…
Synthetic analog and digital circuits for cellular computation and memory.
Purcell, Oliver; Lu, Timothy K
2014-10-01
Biological computation is a major area of focus in synthetic biology because it has the potential to enable a wide range of applications. Synthetic biologists have applied engineering concepts to biological systems in order to construct progressively more complex gene circuits capable of processing information in living cells. Here, we review the current state of computational genetic circuits and describe artificial gene circuits that perform digital and analog computation. We then discuss recent progress in designing gene networks that exhibit memory, and how memory and computation have been integrated to yield more complex systems that can both process and record information. Finally, we suggest new directions for engineering biological circuits capable of computation. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Examining the Relationship between Digital Game Preferences and Computational Thinking Skills
ERIC Educational Resources Information Center
Yildiz, Hatice Durak; Yilmaz, Fatma Gizem Karaoglan; Yilmaz, Ramazan
2017-01-01
The purpose of this study is to identify whether computational thinking skills among secondary school students differ depending on the type of digital games they play. The participants of this study were 202 secondary school students at 5th, 6th, 7th and 8th grades during 2016-2017 academic year. Correlational survey method was used during this…
What's in a Name? The Anatomy of Defining New/Multi/Modal/Digital/Media Texts
ERIC Educational Resources Information Center
Lauer, Claire
2012-01-01
In a 2009 "Computers and Composition" article, I examined how the terms multimedia and multimodal were used in academic and industry situations. This webtext extends that argument to investigate the ways in which a variety of other terms, including digital media and new media, are defined by scholars in the fields of computers and composition and…
ERIC Educational Resources Information Center
Marschalek, Douglas G.
1988-01-01
Describes study of children in grades one, three, and five that examined their active processing and short term memory (STM) of color, contour, and interior pattern of shapes found in computer digitized pictures. Age-related differences are examined, and the role of processing visual information in the learning process is discussed. (12…
Fly-by-Wire Systems Enable Safer, More Efficient Flight
NASA Technical Reports Server (NTRS)
2012-01-01
Using the ultra-reliable Apollo Guidance Computer that enabled the Apollo Moon missions, Dryden Flight Research Center engineers, in partnership with industry leaders such as Cambridge, Massachusetts-based Draper Laboratory, demonstrated that digital computers could be used to fly aircraft. Digital fly-by-wire systems have since been incorporated into large airliners, military jets, revolutionary new aircraft, and even cars and submarines.
ERIC Educational Resources Information Center
Mikelic Preradovic, Nives; Lešin, Gordana; Šagud, Mirjana
2016-01-01
The aim of this study is to investigate perceptions of parents in Croatia towards advantages and disadvantages of computer use in general as well as their children's computer use and to reveal parents' concerns and opinions about digital technology (DT) education in kindergarten. The paper reports on research findings from one of the large public…
Computer Skills and Digital Media Uses among Young Students in Rio de Janeiro
ERIC Educational Resources Information Center
Duarte, Rosalia; Cazelli, Sibele; Migliora, Rita; Coimbra, Carlos
2013-01-01
The main purpose of this paper is provide information relevant for the formulation of new policies for the integration of technology in education from the discussion of research results that analyse computer skills and digital media uses among students (between 12 to 18 years old) from schools in the city of Rio de Janeiro, Brazil. The schools…
NASA Technical Reports Server (NTRS)
Preston, K., Jr.
1972-01-01
The characteristics of the holographic logic computer are discussed. The holographic operation is reviewed from the Fourier transform viewpoint, and the formation of holograms for use in performing digital logic are described. The operation of the computer with an experiment in which the binary identity function is calculated is discussed along with devices for achieving real-time performance. An application in pattern recognition using neighborhood logic is presented.
ERIC Educational Resources Information Center
Tsai, Chia-Wen; Shen, Pei-Di; Lin, Rong-An
2015-01-01
This study investigated, via quasi-experiments, the effects of student-centered project-based learning with initiation (SPBL with Initiation) on the development of students' computing skills. In this study, 96 elementary school students were selected from four class sections taking a course titled "Digital Storytelling" and were assigned…
ERIC Educational Resources Information Center
Hall, Brian R.
2012-01-01
As digital natives continue rolling onto college campuses around the country, the questions surrounding digital ethics grow. Students do not know life without modern technology, computers, mobile devices, the Internet and their lifestyle has developed around this mass. Unlike their predecessors, they do not recognize a difference between the…
A Short History of the Computer.
ERIC Educational Resources Information Center
Leon, George
1984-01-01
Briefly traces the development of computers from the abacus, John Napier's logarithms, the first computer/calculator (known as the Differential Engine), the first computer programming via steel punched cards, the electrical analog computer, electronic digital computer, and the transistor to the microchip of today's computers. (MBR)
Digital Plasma Control System for Alcator C-Mod
NASA Astrophysics Data System (ADS)
Ferrara, M.; Wolfe, S.; Stillerman, J.; Fredian, T.; Hutchinson, I.
2004-11-01
A digital plasma control system (DPCS) has been designed to replace the present C-Mod system, which is based on hybrid analog-digital computer. The initial implementation of DPCS comprises two 64 channel, 16 bit, low-latency cPCI digitizers, each with 16 analog outputs, controlled by a rack-mounted single-processor Linux server, which also serves as the compute engine. A prototype system employing three older 32 channel digitizers was tested during the 2003-04 campaign. The hybrid's linear PID feedback system was emulated by IDL code executing a synchronous loop, using the same target waveforms and control parameters. Reliable real-time operation was accomplished under a standard Linux OS (RH9) by locking memory and disabling interrupts during the plasma pulse. The DPCS-computed outputs agreed to within a few percent with those produced by the hybrid system, except for discrepancies due to offsets and non-ideal behavior of the hybrid circuitry. The system operated reliably, with no sample loss, at more than twice the 10kHz design specification, providing extra time for implementing more advanced control algorithms. The code is fault-tolerant and produces consistent output waveforms even with 10% sample loss.
Geometric processing of digital images of the planets
NASA Technical Reports Server (NTRS)
Edwards, Kathleen
1987-01-01
New procedures and software have been developed for geometric transformation of images to support digital cartography of the planets. The procedures involve the correction of spacecraft camera orientation of each image with the use of ground control and the transformation of each image to a Sinusoidal Equal-Area map projection with an algorithm which allows the number of transformation calculations to vary as the distortion varies within the image. When the distortion is low in an area of an image, few transformation computations are required, and most pixels can be interpolated. When distortion is extreme, the location of each pixel is computed. Mosaics are made of these images and stored as digital databases. Completed Sinusoidal databases may be used for digital analysis and registration with other spatial data. They may also be reproduced as published image maps by digitally transforming them to appropriate map projections.
Digital templating for THA: a simple computer-assisted application for complex hip arthritis cases.
Hafez, Mahmoud A; Ragheb, Gad; Hamed, Adel; Ali, Amr; Karim, Said
2016-10-01
Total hip arthroplasty (THA) is the standard procedure for end-stage arthritis of the hip. Its technical success relies on preoperative planning of the surgical procedure and virtual setup of the operative performance. Digital hip templating is one methodology of preoperative planning for THA which requires a digital preoperative radiograph and a computer with special software. This is a prospective study involving 23 patients (25 hips) who were candidates for complex THA surgery (unilateral or bilateral). Digital templating is done by radiographic assessment using radiographic magnification correction, leg length discrepancy and correction measurements, acetabular component and femoral component templating as well as neck resection measurement. The overall accuracy for templating the stem implant's exact size is 81%. This percentage increased to 94% when considering sizing within 1 size. Digital templating has proven effective, reliable and essential technique for preoperative planning and accurate prediction of THA sizing and alignment.
Computer aided design of digital controller for radial active magnetic bearings
NASA Technical Reports Server (NTRS)
Cai, Zhong; Shen, Zupei; Zhang, Zuming; Zhao, Hongbin
1992-01-01
A five degree of freedom Active Magnetic Bearing (AMB) system is developed which is controlled by digital controllers. The model of the radial AMB system is linearized and the state equation is derived. Based on the state variables feedback theory, digital controllers are designed. The performance of the controllers are evaluated according to experimental results. The Computer Aided Design (CAD) method is used to design controllers for magnetic bearings. The controllers are implemented with a digital signal processing (DSP) system. The control algorithms are realized with real-time programs. It is very easy to change the controller by changing or modifying the programs. In order to identify the dynamic parameters of the controlled magnetic system, a special experiment was carried out. Also, the online Recursive Least Squares (RLS) parameter identification method is studied. It can be realized with the digital controllers. Online parameter identification is essential for the realization of an adaptive controller.
NASA Technical Reports Server (NTRS)
Hrach, F. J.; Arpasi, D. J.; Bruton, W. M.
1975-01-01
A self-learning, sensor fail-operational, control system for the TF30-P-3 afterburning turbofan engine was designed and evaluated. The sensor fail-operational control system includes a digital computer program designed to operate in conjunction with the standard TF30-P-3 bill-of-materials control. Four engine measurements and two compressor face measurements are tested. If any engine measurements are found to have failed, they are replaced by values synthesized from computer-stored information. The control system was evaluated by using a realtime, nonlinear, hybrid computer engine simulation at sea level static condition, at a typical cruise condition, and at several extreme flight conditions. Results indicate that the addition of such a system can improve the reliability of an engine digital control system.
Digital tape unit test facility software
NASA Technical Reports Server (NTRS)
Jackson, J. T.
1971-01-01
Two computer programs are described which are used for the collection and analysis of data from the digital tape unit test facility (DTUTF). The data are the recorded results of skew tests made on magnetic digital tapes which are used on computers as input/output media. The results of each tape test are keypunched onto an 80 column computer card. The format of the card is checked and the card image is stored on a master summary tape via the DTUTF card checking and tape updating system. The master summary tape containing the results of all the tape tests is then used for analysis as input to the DTUTF histogram generating system which produces a histogram of skew vs. date for selected data, followed by some statistical analysis of the data.
Cost-effective handling of digital medical images in the telemedicine environment.
Choong, Miew Keen; Logeswaran, Rajasvaran; Bister, Michel
2007-09-01
This paper concentrates on strategies for less costly handling of medical images. Aspects of digitization using conventional digital cameras, lossy compression with good diagnostic quality, and visualization through less costly monitors are discussed. For digitization of film-based media, subjective evaluation of the suitability of digital cameras as an alternative to the digitizer was undertaken. To save on storage, bandwidth and transmission time, the acceptable degree of compression with diagnostically no loss of important data was studied through randomized double-blind tests of the subjective image quality when compression noise was kept lower than the inherent noise. A diagnostic experiment was undertaken to evaluate normal low cost computer monitors as viable viewing displays for clinicians. The results show that conventional digital camera images of X-ray images were diagnostically similar to the expensive digitizer. Lossy compression, when used moderately with the imaging noise to compression noise ratio (ICR) greater than four, can bring about image improvement with better diagnostic quality than the original image. Statistical analysis shows that there is no diagnostic difference between expensive high quality monitors and conventional computer monitors. The results presented show good potential in implementing the proposed strategies to promote widespread cost-effective telemedicine and digital medical environments. 2006 Elsevier Ireland Ltd
Construction of a Digital Learning Environment Based on Cloud Computing
ERIC Educational Resources Information Center
Ding, Jihong; Xiong, Caiping; Liu, Huazhong
2015-01-01
Constructing the digital learning environment for ubiquitous learning and asynchronous distributed learning has opened up immense amounts of concrete research. However, current digital learning environments do not fully fulfill the expectations on supporting interactive group learning, shared understanding and social construction of knowledge.…
Creating the Future of Games and Learning
ERIC Educational Resources Information Center
Squire, Kurt
2015-01-01
Games for learning are poised to enter mainstream education. Several factors driving this movement are the following: (1) Digital distribution through cloud computing services and ubiquitous connectivity which will make digital learning tools--such as games--affordable and easily accessible; (2) The proliferation of digital devices; (3) Digital…
Designing Digital Environments for Art Education/Exploration.
ERIC Educational Resources Information Center
Milekic, Slavko
2000-01-01
Examines the role of digital technology in the context of art education and art exploration. Discusses the development of digital environments as the next step in the evolution of traditional computers, whose main characteristic is support for simultaneous multiple-user interactions and for social and collaborative activities. (LRW)
Microcomputer-Based Digital Signal Processing Laboratory Experiments.
ERIC Educational Resources Information Center
Tinari, Jr., Rocco; Rao, S. Sathyanarayan
1985-01-01
Describes a system (Apple II microcomputer interfaced to flexible, custom-designed digital hardware) which can provide: (1) Fast Fourier Transform (FFT) computation on real-time data with a video display of spectrum; (2) frequency synthesis experiments using the inverse FFT; and (3) real-time digital filtering experiments. (JN)
Digital Audio Tape: Yet Another Archival Media?
ERIC Educational Resources Information Center
Vanker, Anthony D.
1989-01-01
Provides an introduction to the technical aspects of digital audiotape and compares it to other computer storage devices such as optical data disks and magnetic tape cartridges in terms of capacity, transfer rate, and cost. The current development of digital audiotape standards is also discussed. (five references) (CLB)
28 CFR 75.6 - Statement describing location of books and records.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Statement describing location of books... of books and records. (a) Any producer of any book, magazine, periodical, film, videotape, digitally... the book, magazine, periodical, film, videotape, digitally- or computer-manipulated image, digital...
28 CFR 75.6 - Statement describing location of books and records.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Statement describing location of books... of books and records. (a) Any producer of any book, magazine, periodical, film, videotape, digitally... the book, magazine, periodical, film, videotape, digitally- or computer-manipulated image, digital...
28 CFR 75.6 - Statement describing location of books and records.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Statement describing location of books... of books and records. (a) Any producer of any book, magazine, periodical, film, videotape, digitally... the book, magazine, periodical, film, videotape, digitally- or computer-manipulated image, digital...
28 CFR 75.6 - Statement describing location of books and records.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Statement describing location of books... of books and records. (a) Any producer of any book, magazine, periodical, film, videotape, digitally... the book, magazine, periodical, film, videotape, digitally- or computer-manipulated image, digital...
Digital Social Network Mining for Topic Discovery
NASA Astrophysics Data System (ADS)
Moradianzadeh, Pooya; Mohi, Maryam; Sadighi Moshkenani, Mohsen
Networked computers are expanding more and more around the world, and digital social networks becoming of great importance for many people's work and leisure. This paper mainly focused on discovering the topic of exchanging information in digital social network. In brief, our method is to use a hierarchical dictionary of related topics and words that mapped to a graph. Then, with comparing the extracted keywords from the context of social network with graph nodes, probability of relation between context and desired topics will be computed. This model can be used in many applications such as advertising, viral marketing and high-risk group detection.
Digital Mammography with a Mosaic of CCD Arrays
NASA Technical Reports Server (NTRS)
Jalink, Antony, Jr. (Inventor); McAdoo, James A. (Inventor)
1998-01-01
A digital mammography device uses a mosaic of electronic digital imaging arrays to scan an x-ray image is discussed. The mosaic of arrays is repositioned several times to expose different portions of the image, until the entire image is scanned. The data generated by the arrays during each exposure is stored in a computer. After the final exposure, the computer combines data of the several partial images to produce a composite of the original x-ray image. An aperture plate is used to reduce scatter and the overall exposure of the patient to x-rays.
Satellite-aided evaluation of population exposure to air pollution
NASA Technical Reports Server (NTRS)
Todd, W. J.; George, A. J., Jr.; Bryant, N. A.
1979-01-01
The evaluation of population exposure to air pollution through the computer processing of Landsat digital land use data, along with total suspended particulate estimates and population data by census tracts, is demonstrated. Digital image processing was employed to analyze simultaneously data from Landsat MSS bands 4 through 7 in order to extract land use and land cover information. The three data sets were spatially registered in a digital format, compatible with integrated computer processing, and cross-tabulated. A map illustrating relative air quality by 2-sq km cells for the residential population in the Portland, Oregon area is obtained.
Battlefield awareness computers: the engine of battlefield digitization
NASA Astrophysics Data System (ADS)
Ho, Jackson; Chamseddine, Ahmad
1997-06-01
To modernize the army for the 21st century, the U.S. Army Digitization Office (ADO) initiated in 1995 the Force XXI Battle Command Brigade-and-Below (FBCB2) Applique program which became a centerpiece in the U.S. Army's master plan to win future information wars. The Applique team led by TRW fielded a 'tactical Internet' for Brigade and below command to demonstrate the advantages of 'shared situation awareness' and battlefield digitization in advanced war-fighting experiments (AWE) to be conducted in March 1997 at the Army's National Training Center in California. Computing Devices is designated the primary hardware developer for the militarized version of the battlefield awareness computers. The first generation of militarized battlefield awareness computer, designated as the V3 computer, was an integration of off-the-shelf components developed to meet the agressive delivery requirements of the Task Force XXI AWE. The design efficiency and cost effectiveness of the computer hardware were secondary in importance to delivery deadlines imposed by the March 1997 AWE. However, declining defense budgets will impose cost constraints on the Force XXI production hardware that can only be met by rigorous value engineering to further improve design optimization for battlefield awareness without compromising the level of reliability the military has come to expect in modern military hardened vetronics. To answer the Army's needs for a more cost effective computing solution, Computing Devices developed a second generation 'combat ready' battlefield awareness computer, designated the V3+, which is designed specifically to meet the upcoming demands of Force XXI (FBCB2) and beyond. The primary design objective is to achieve a technologically superior design, value engineered to strike an optimal balance between reliability, life cycle cost, and procurement cost. Recognizing that the diverse digitization demands of Force XXI cannot be adequately met by any one computer hardware solution, Computing Devices is planning to develop a notebook sized military computer designed for space limited vehicle-mounted applications, as well as a high-performance portable workstation equipped with a 19', full color, ultra-high resolution and high brightness active matrix liquid crystal display (AMLCD) targeting the command posts and tactical operations centers (TOC) applications. Together with the wearable computers Computing Devices developed at the Minneapolis facility for dismounted soldiers, Computing Devices will have a complete suite of interoperable battlefield awareness computers spanning the entire spectrum of battle digitization operating environments. Although this paper's primary focus is on a second generation 'combat ready' battlefield awareness computer or the V3+, this paper also briefly discusses the extension of the V3+ architecture to address the needs of the embedded and command post applications.3080
NASA Astrophysics Data System (ADS)
Grubert, Emily; Siders, Anne
2016-09-01
Digitally-aided reviews of large bodies of text-based information, such as academic literature, are growing in capability but are not yet common in environmental fields. Environmental sciences and studies can benefit from application of digital tools to create comprehensive, replicable, interdisciplinary reviews that provide rapid, up-to-date, and policy-relevant reports of existing work. This work reviews the potential for applications of computational text mining and analysis tools originating in the humanities to environmental science and policy questions. Two process-oriented case studies of digitally-aided environmental literature reviews and meta-analyses illustrate potential benefits and limitations. A medium-sized, medium-resolution review (∼8000 journal abstracts and titles) focuses on topic modeling as a rapid way to identify thematic changes over time. A small, high-resolution review (∼300 full text journal articles) combines collocation and network analysis with manual coding to synthesize and question empirical field work. We note that even small digitally-aided analyses are close to the upper limit of what can be done manually. Established computational methods developed in humanities disciplines and refined by humanities and social science scholars to interrogate large bodies of textual data are applicable and useful in environmental sciences but have not yet been widely applied. Two case studies provide evidence that digital tools can enhance insight. Two major conclusions emerge. First, digital tools enable scholars to engage large literatures rapidly and, in some cases, more comprehensively than is possible manually. Digital tools can confirm manually identified patterns or identify additional patterns visible only at a large scale. Second, digital tools allow for more replicable and transparent conclusions to be drawn from literature reviews and meta-analyses. The methodological subfields of digital humanities and computational social sciences will likely continue to create innovative tools for analyzing large bodies of text, providing opportunities for interdisciplinary collaboration with the environmental fields.
The direction of cloud computing for Malaysian education sector in 21st century
NASA Astrophysics Data System (ADS)
Jaafar, Jazurainifariza; Rahman, M. Nordin A.; Kadir, M. Fadzil A.; Shamsudin, Syadiah Nor; Saany, Syarilla Iryani A.
2017-08-01
In 21st century, technology has turned learning environment into a new way of education to make learning systems more effective and systematic. Nowadays, education institutions are faced many challenges to ensure the teaching and learning process is running smoothly and manageable. Some of challenges in the current education management are lack of integrated systems, high cost of maintenance, difficulty of configuration and deployment as well as complexity of storage provision. Digital learning is an instructional practice that use technology to make learning experience more effective, provides education process more systematic and attractive. Digital learning can be considered as one of the prominent application that implemented under cloud computing environment. Cloud computing is a type of network resources that provides on-demands services where the users can access applications inside it at any location and no time border. It also promises for minimizing the cost of maintenance and provides a flexible of data storage capacity. The aim of this article is to review the definition and types of cloud computing for improving digital learning management as required in the 21st century education. The analysis of digital learning context focused on primary school in Malaysia. Types of cloud applications and services in education sector are also discussed in the article. Finally, gap analysis and direction of cloud computing in education sector for facing the 21st century challenges are suggested.
Chalazonitis, A N; Koumarianos, D; Tzovara, J; Chronopoulos, P
2003-06-01
Over the past decade, the technology that permits images to be digitized and the reduction in the cost of digital equipment allows quick digital transfer of any conventional radiological film. Images then can be transferred to a personal computer, and several software programs are available that can manipulate their digital appearance. In this article, the fundamentals of digital imaging are discussed, as well as the wide variety of optional adjustments that the Adobe Photoshop 6.0 (Adobe Systems, San Jose, CA) program can offer to present radiological images with satisfactory digital imaging quality.
Design Principles of Next-Generation Digital Gaming for Education.
ERIC Educational Resources Information Center
Squire, Kurt; Jenkins, Henry; Holland, Walter; Miller, Heather; O'Driscoll, Alice; Tan, Katie Philip; Todd, Katie.
2003-01-01
Discusses the rapid growth of digital games, describes research at MIT that is exploring the potential of digital games for supporting learning, and offers hypotheses about the design of next-generation educational video and computer games. Highlights include simulations and games; and design principles, including context and using information to…
Three Essays on Digital Evolution
ERIC Educational Resources Information Center
Zhang, Zhewei
2016-01-01
Digital products are rapidly shaping our world into a ubiquitous computing world. Because of its unique characteristics, digital artifacts are generative and highly evolving through the recombination of existing elements as well as by the invention of new elements. In this thesis, I first propose an evolutionary view to examine how digital…
How Digital Scaffolds in Games Direct Problem-Solving Behaviors
ERIC Educational Resources Information Center
Sun, Chuen-Tsai; Wang, Dai-Yi; Chan, Hui-Ling
2011-01-01
Digital systems offer computational power and instant feedback. Game designers are using these features to create scaffolding tools to reduce player frustration. However, researchers are finding some unexpected effects of scaffolding on strategy development and problem-solving behaviors. We used a digital Sudoku game named "Professor Sudoku" to…
Digital Natives Come to Preschool: Implications for Early Childhood Practice
ERIC Educational Resources Information Center
Zevenbergen, Robyn
2007-01-01
This article explores the implications of young learners' dispositions towards the use of digital technologies in contemporary early childhood settings. It is proposed that young learners have grown up in very different social conditions from previous generations, mainly through the saturation of digital technologies, in particular computers. This…
Reaching Digital Natives on Their Terms
ERIC Educational Resources Information Center
Dessoff, Alan
2010-01-01
From replacing print textbooks with digital content created by teachers or gathered from outside sources to encouraging students to explore the world around them digitally, many districts are creating a new type of student-friendly teaching and learning environment that goes beyond just adding computers to classrooms. Through a wide range of…
Digital Data Collection and Analysis: Application for Clinical Practice
ERIC Educational Resources Information Center
Ingram, Kelly; Bunta, Ferenc; Ingram, David
2004-01-01
Technology for digital speech recording and speech analysis is now readily available for all clinicians who use a computer. This article discusses some advantages of moving from analog to digital recordings and outlines basic recording procedures. The purpose of this article is to familiarize speech-language pathologists with computerized audio…
Camera! Action! Collaborate with Digital Moviemaking
ERIC Educational Resources Information Center
Swan, Kathleen Owings; Hofer, Mark; Levstik, Linda S.
2007-01-01
Broadly defined, digital moviemaking integrates a variety of media (images, sound, text, video, narration) to communicate with an audience. There is near-ubiquitous access to the necessary software (MovieMaker and iMovie are bundled free with their respective operating systems) and hardware (computers with Internet access, digital cameras, etc.).…
Digital Simulations: Facilitating Transition for Students with Disabilities
ERIC Educational Resources Information Center
Zionch, Allenda
2011-01-01
Today's students are digital natives. From computers to MP3 players, the everyday use of technology in society underscores the necessity of using technology in education. The use of digital simulations especially has had positive outcomes for students with disabilities in generalizing various life skills necessary for transition beyond high…
Engineer Modeling Study. Volume II. Users Manual.
1982-09-01
Distribution Center, Digital Equip- ment Corporation, 1980). The following paragraphs briefly describe each of the major input sections...abbreviation 3. A sequence number for post-processing 4. Clock time 5. Order number pointer (six digits ) 6. Job number pointer (six digits ) 7. Unit number...KIT) Users Manual (Boeing Computer % Services, Inc., 1977). S VAX/VMS Users Manual. Volume 3A (Software Distribution Center, Digital Equipment
ERIC Educational Resources Information Center
Gyabak, Khendum; Godina, Heriberto
2011-01-01
This qualitative study examines the use of digital storytelling as an instructional intervention for bridging the digital divide among public school students in rural Bhutan. Primary participants for the study included elementary school children who had never been previously exposed to computer technology and were recipients of a donated classroom…
Reducing the Digital Divide among Children Who Received Desktop or Hybrid Computers for the Home
ERIC Educational Resources Information Center
Zilka, Gila Cohen
2016-01-01
Researchers and policy makers have been exploring ways to reduce the digital divide. Parameters commonly used to examine the digital divide worldwide, as well as in this study, are: (a) the digital divide in the accessibility and mobility of the ICT infrastructure and of the content infrastructure (e.g., sites used in school); and (b) the digital…
Computer Aided Detection of Breast Masses in Digital Tomosynthesis
2008-06-01
the suspicious CAD location were extracted. For the second set, 256x256 ROIs representing the - 8 - summed slab of 5 slices (5 mm) were extracted...region hotelling observer, digital tomosynthesis, multi-slice CAD algorithms, biopsy 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18...developing computer-aided detection ( CAD ) tools for mammography. Although these tools have shown promise in identifying calcifications, detecting
ERIC Educational Resources Information Center
Nunn, Samuel
1993-01-01
Assessed the impact of the Mobile Digital Terminal technology (computers used to communicate with remote crime databases) on motor vehicle theft clearance (arresting a perpetrator) and recovery rates in Fort Worth (Texas), using a time series analysis. Impact has been ambiguous, with little evidence of improved clearance or recovery. (SLD)
A real-time digital computer program for the simulation of a single rotor helicopter
NASA Technical Reports Server (NTRS)
Houck, J. A.; Gibson, L. H.; Steinmetz, G. G.
1974-01-01
A computer program was developed for the study of a single-rotor helicopter on the Langley Research Center real-time digital simulation system. Descriptions of helicopter equations and data, program subroutines (including flow charts and listings), real-time simulation system routines, and program operation are included. Program usage is illustrated by standard check cases and a representative flight case.
NASA Technical Reports Server (NTRS)
Danielson, E. F.; Hipskind, R. S.; Gaines, S. E.
1980-01-01
Results are presented from computer processing and digital filtering of radiosonde and radar tracking data obtained during the ITCZ experiment when coordinated measurements were taken daily over a 16 day period across the Panama Canal Zone. The temperature relative humidity and wind velocity profiles are discussed.
A computational model of selection by consequences.
McDowell, J J
2004-05-01
Darwinian selection by consequences was instantiated in a computational model that consisted of a repertoire of behaviors undergoing selection, reproduction, and mutation over many generations. The model in effect created a digital organism that emitted behavior continuously. The behavior of this digital organism was studied in three series of computational experiments that arranged reinforcement according to random-interval (RI) schedules. The quantitative features of the model were varied over wide ranges in these experiments, and many of the qualitative features of the model also were varied. The digital organism consistently showed a hyperbolic relation between response and reinforcement rates, and this hyperbolic description of the data was consistently better than the description provided by other, similar, function forms. In addition, the parameters of the hyperbola varied systematically with the quantitative, and some of the qualitative, properties of the model in ways that were consistent with findings from biological organisms. These results suggest that the material events responsible for an organism's responding on RI schedules are computationally equivalent to Darwinian selection by consequences. They also suggest that the computational model developed here is worth pursuing further as a possible dynamic account of behavior.
Xu, Qun; Wang, Xianchao; Xu, Chao
2017-06-01
Multiplication with traditional electronic computers is faced with a low calculating accuracy and a long computation time delay. To overcome these problems, the modified signed digit (MSD) multiplication routine is established based on the MSD system and the carry-free adder. Also, its parallel algorithm and optimization techniques are studied in detail. With the help of a ternary optical computer's characteristics, the structured data processor is designed especially for the multiplication routine. Several ternary optical operators are constructed to perform M transformations and summations in parallel, which has accelerated the iterative process of multiplication. In particular, the routine allocates data bits of the ternary optical processor based on digits of multiplication input, so the accuracy of the calculation results can always satisfy the users. Finally, the routine is verified by simulation experiments, and the results are in full compliance with the expectations. Compared with an electronic computer, the MSD multiplication routine is not only good at dealing with large-value data and high-precision arithmetic, but also maintains lower power consumption and fewer calculating delays.
NASA Technical Reports Server (NTRS)
Svalbonas, V.; Levine, H.; Ogilvie, P.
1975-01-01
Engineering programming information is presented for the STARS-2P (shell theory automated for rotational structures-2P (plasticity)) digital computer program, and FORTRAN 4 was used in writing the various subroutines. The execution of this program requires the use of thirteen temporary storage units. The program was initially written and debugged on the IBM 370-165 computer and converted to the UNIVAC 1108 computer, where it utilizes approximately 60,000 words of core. Only basic FORTRAN library routines are required by the program: sine, cosine, absolute value, and square root.
Roskovensky, John K [Albuquerque, NM
2009-01-20
A method of detecting clouds in a digital image comprising, for an area of the digital image, determining a reflectance value in at least three discrete electromagnetic spectrum bands, computing a first ratio of one reflectance value minus another reflectance value and the same two values added together, computing a second ratio of one reflectance value and another reflectance value, choosing one of the reflectance values, and concluding that an opaque cloud exists in the area if the results of each of the two computing steps and the choosing step fall within three corresponding predetermined ranges.
Measurement of fault latency in a digital avionic mini processor, part 2
NASA Technical Reports Server (NTRS)
Mcgough, J.; Swern, F.
1983-01-01
The results of fault injection experiments utilizing a gate-level emulation of the central processor unit of the Bendix BDX-930 digital computer are described. Several earlier programs were reprogrammed, expanding the instruction set to capitalize on the full power of the BDX-930 computer. As a final demonstration of fault coverage an extensive, 3-axis, high performance flght control computation was added. The stages in the development of a CPU self-test program emphasizing the relationship between fault coverage, speed, and quantity of instructions were demonstrated.
NASA Technical Reports Server (NTRS)
Denning, Peter J.
1988-01-01
The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.
Flynn, Allen J; Bahulekar, Namita; Boisvert, Peter; Lagoze, Carl; Meng, George; Rampton, James; Friedman, Charles P
2017-01-01
Throughout the world, biomedical knowledge is routinely generated and shared through primary and secondary scientific publications. However, there is too much latency between publication of knowledge and its routine use in practice. To address this latency, what is actionable in scientific publications can be encoded to make it computable. We have created a purpose-built digital library platform to hold, manage, and share actionable, computable knowledge for health called the Knowledge Grid Library. Here we present it with its system architecture.
Advanced reliability modeling of fault-tolerant computer-based systems
NASA Technical Reports Server (NTRS)
Bavuso, S. J.
1982-01-01
Two methodologies for the reliability assessment of fault tolerant digital computer based systems are discussed. The computer-aided reliability estimation 3 (CARE 3) and gate logic software simulation (GLOSS) are assessment technologies that were developed to mitigate a serious weakness in the design and evaluation process of ultrareliable digital systems. The weak link is based on the unavailability of a sufficiently powerful modeling technique for comparing the stochastic attributes of one system against others. Some of the more interesting attributes are reliability, system survival, safety, and mission success.
Qubits and quantum Hamiltonian computing performances for operating a digital Boolean 1/2-adder
NASA Astrophysics Data System (ADS)
Dridi, Ghassen; Faizy Namarvar, Omid; Joachim, Christian
2018-04-01
Quantum Boolean (1 + 1) digits 1/2-adders are designed with 3 qubits for the quantum computing (Qubits) and 4 quantum states for the quantum Hamiltonian computing (QHC) approaches. Detailed analytical solutions are provided to analyse the time operation of those different 1/2-adder gates. QHC is more robust to noise than Qubits and requires about the same amount of energy for running its 1/2-adder logical operations. QHC is faster in time than Qubits but its logical output measurement takes longer.
Issues for bringing digital libraries into public use
NASA Technical Reports Server (NTRS)
Flater, David W.; Yesha, Yelena
1993-01-01
In much the same way that the field of artificial intelligence produced a cult which fervently believed that computers would soon think like human beings, the existence of electronic books has resurrected the paperless society as a utopian vision to some, an apocalyptic horror to others. In this essay we have attempted to provide realistic notions of what digital libraries are likely to become if they are a popular success. E-books are capable of subsuming most of the media we use today and have the potential for added functionality by being interactive. The environmental impact of having millions more computers will be offset to some degree, perhaps even exceeded, by the fact that televisions, stereos, VCR's, CD players, newspapers, magazines, and books will become part of the computer system or be made redundant. On the whole, large-scale use of digital libraries is likely to be a winning proposition. Whether or not this comes to pass depends on the directions taken by today's researchers and software developers. By involving the public, the effort being put into digital libraries can be leveraged into something which is big enough to make a real change for the better. If digital libraries remain the exclusive property of government, universities, and large research firms, then large parts of the world will remain without digital libraries for years to come, just as they have remained without digital phone service for far too long. If software companies try to scuttle the project by patenting crucial algorithms and using proprietary data formats, all of us will suffer. Let us reverse the errors of the past and create a truly open digital library system.
Simpson, V; Hughes, M; Wilkinson, J; Herrick, A L; Dinsdale, G
2018-03-01
Digital ulcers are a major problem in patients with systemic sclerosis (SSc), causing severe pain and impairment of hand function. In addition, digital ulcers heal slowly and sometimes become infected, which can lead to gangrene and necessitate amputation if appropriate intervention is not taken. A reliable, objective method for assessing digital ulcer healing or progression is needed in both the clinical and research arenas. This study was undertaken to compare 2 computer-assisted planimetry methods of measurement of digital ulcer area on photographs (ellipse and freehand regions of interest [ROIs]), and to assess the reliability of photographic calibration and the 2 methods of area measurement. Photographs were taken of 107 digital ulcers in 36 patients with SSc spectrum disease. Three raters assessed the photographs. Custom software allowed raters to calibrate photograph dimensions and draw ellipse or freehand ROIs. The shapes and dimensions of the ROIs were saved for further analysis. Calibration (by a single rater performing 5 repeats per image) produced an intraclass correlation coefficient (intrarater reliability) of 0.99. The mean ± SD areas of digital ulcers assessed using ellipse and freehand ROIs were 18.7 ± 20.2 mm 2 and 17.6 ± 19.3 mm 2 , respectively. Intrarater and interrater reliability of the ellipse ROI were 0.97 and 0.77, respectively. For the freehand ROI, the intrarater and interrater reliability were 0.98 and 0.76, respectively. Our findings indicate that computer-assisted planimetry methods applied to SSc-related digital ulcers can be extremely reliable. Further work is needed to move toward applying these methods as outcome measures for clinical trials and in clinical settings. © 2017, American College of Rheumatology.
Historical perspective on computer development and glossary of terms.
Honeyman, J C; Dwyer, S J
1993-01-01
This article contains a concise history of the development of mechanical and electronic computers, descriptions of the milestones in software development, discussion of the introduction and adoption of computers in radiology, and a glossary of computer terms used frequently in radiology. One of the earliest devices designed to mechanize calculations was the calculating clock, built in 1623. The first programmable electronic computer, the ENIAC (electronic numerical integration and computer), was completed in 1945 at the University of Pennsylvania. Software has developed from early machine language through fourth-generation languages and graphic user interfaces used today. The computer was introduced to radiology initially in the 1960s in nuclear medicine and is now incorporated in many digital imaging modalities throughout radiology. The development of picture archiving and communication systems has resulted in the implementation of several totally digital departments of radiology.
Chen, Zhiyu; Li, Ya; Deng, Xuliang; Wang, Xinzhi
2014-06-01
Fiber-reinforced composite dowels have been widely used for their superior biomechanical properties; however, their preformed shape cannot fit irregularly shaped root canals. This study aimed to describe a novel computer-aided method to create a custom-made one-piece dowel-and-core based on the digitization of impressions and clinical standard crown preparations. A standard maxillary die stone model containing three prepared teeth each (maxillary lateral incisor, canine, premolar) requiring dowel restorations was made. It was then mounted on an average value articulator with the mandibular stone model to simulate natural occlusion. Impressions for each tooth were obtained using vinylpolysiloxane with a sectional dual-arch tray and digitized with an optical scanner. The dowel-and-core virtual model was created by slicing 3D dowel data from impression digitization with core data selected from a standard crown preparation database of 107 records collected from clinics and digitized. The position of the chosen digital core was manually regulated to coordinate with the adjacent teeth to fulfill the crown restorative requirements. Based on virtual models, one-piece custom dowel-and-cores for three experimental teeth were milled from a glass fiber block with computer-aided manufacturing techniques. Furthermore, two patients were treated to evaluate the practicality of this new method. The one-piece glass fiber dowel-and-core made for experimental teeth fulfilled the clinical requirements for dowel restorations. Moreover, two patients were treated to validate the technique. This novel computer-aided method to create a custom one-piece glass fiber dowel-and-core proved to be practical and efficient. © 2013 by the American College of Prosthodontists.
NASA Astrophysics Data System (ADS)
Moore, Craig S.; Wood, Tim J.; Saunderson, John R.; Beavis, Andrew W.
2017-09-01
The use of computer simulated digital x-radiographs for optimisation purposes has become widespread in recent years. To make these optimisation investigations effective, it is vital simulated radiographs contain accurate anatomical and system noise. Computer algorithms that simulate radiographs based solely on the incident detector x-ray intensity (‘dose’) have been reported extensively in the literature. However, while it has been established for digital mammography that x-ray beam quality is an important factor when modelling noise in simulated images there are no such studies for diagnostic imaging of the chest, abdomen and pelvis. This study investigates the influence of beam quality on image noise in a digital radiography (DR) imaging system, and incorporates these effects into a digitally reconstructed radiograph (DRR) computer simulator. Image noise was measured on a real DR imaging system as a function of dose (absorbed energy) over a range of clinically relevant beam qualities. Simulated ‘absorbed energy’ and ‘beam quality’ DRRs were then created for each patient and tube voltage under investigation. Simulated noise images, corrected for dose and beam quality, were subsequently produced from the absorbed energy and beam quality DRRs, using the measured noise, absorbed energy and beam quality relationships. The noise images were superimposed onto the noiseless absorbed energy DRRs to create the final images. Signal-to-noise measurements in simulated chest, abdomen and spine images were within 10% of the corresponding measurements in real images. This compares favourably to our previous algorithm where images corrected for dose only were all within 20%.
Shade matching assisted by digital photography and computer software.
Schropp, Lars
2009-04-01
To evaluate the efficacy of digital photographs and graphic computer software for color matching compared to conventional visual matching. The shade of a tab from a shade guide (Vita 3D-Master Guide) placed in a phantom head was matched to a second guide of the same type by nine observers. This was done for twelve selected shade tabs (tests). The shade-matching procedure was performed visually in a simulated clinic environment and with digital photographs, and the time spent for both procedures was recorded. An alternative arrangement of the shade tabs was used in the digital photographs. In addition, a graphic software program was used for color analysis. Hue, chroma, and lightness values of the test tab and all tabs of the second guide were derived from the digital photographs. According to the CIE L*C*h* color system, the color differences between the test tab and tabs of the second guide were calculated. The shade guide tab that deviated least from the test tab was determined to be the match. Shade matching performance by means of graphic software was compared with the two visual methods and tested by Chi-square tests (alpha= 0.05). Eight of twelve test tabs (67%) were matched correctly by the computer software method. This was significantly better (p < 0.02) than the performance of the visual shade matching methods conducted in the simulated clinic (32% correct match) and with photographs (28% correct match). No correlation between time consumption for the visual shade matching methods and frequency of correct match was observed. Shade matching assisted by digital photographs and computer software was significantly more reliable than by conventional visual methods.
42 CFR 37.42 - Chest radiograph specifications-digital radiography systems.
Code of Federal Regulations, 2014 CFR
2014-10-01
... resolution, modulation transfer function (MTF), image signal-to-noise and detective quantum efficiency must... Information Object Definitions, sections: Computed Radiography Image Information Object Definition; Digital X...
ROC Analysis of Chest Radiographs Using Computed Radiography and Conventional Analog Films
NASA Astrophysics Data System (ADS)
Morioka, Craig A.; Brown, Kathy; Hayrapetian, Alek S.; Kangarloo, Hooshang; Balter, Stephen; Huang, H. K.
1989-05-01
Receiver operating characteristic is used to compare the image quality of films obtained digitally using computed radiography (CR) and conventionally using analog film following fluoroscopic examination. Similar radiological views were obtained by both modalities. Twenty-four cases, some with a solitary noncalcified nodule and/or pneumothorax, were collected. Ten radiologists have been tested viewing analog and CR digital films separately. Final results indicate that there is no statistically significant difference in the ability to detect either a pneumothorax or a solitary noncalcified nodule when comparing CR digital film with conventional analog film. However, there is a trend that indicated the area under the ROC curves for detection of either a pneumothorax or solitary noncalcified nodule were greater for the analog film than for the digital film.
Digital hand atlas and computer-aided bone age assessment via the Web
NASA Astrophysics Data System (ADS)
Cao, Fei; Huang, H. K.; Pietka, Ewa; Gilsanz, Vicente
1999-07-01
A frequently used assessment method of bone age is atlas matching by a radiological examination of a hand image against a reference set of atlas patterns of normal standards. We are in a process of developing a digital hand atlas with a large standard set of normal hand and wrist images that reflect the skeletal maturity, race and sex difference, and current child development. The digital hand atlas will be used for a computer-aided bone age assessment via Web. We have designed and partially implemented a computer-aided diagnostic (CAD) system for Web-based bone age assessment. The system consists of a digital hand atlas, a relational image database and a Web-based user interface. The digital atlas is based on a large standard set of normal hand an wrist images with extracted bone objects and quantitative features. The image database uses a content- based indexing to organize the hand images and their attributes and present to users in a structured way. The Web-based user interface allows users to interact with the hand image database from browsers. Users can use a Web browser to push a clinical hand image to the CAD server for a bone age assessment. Quantitative features on the examined image, which reflect the skeletal maturity, will be extracted and compared with patterns from the atlas database to assess the bone age. The relevant reference imags and the final assessment report will be sent back to the user's browser via Web. The digital atlas will remove the disadvantages of the currently out-of-date one and allow the bone age assessment to be computerized and done conveniently via Web. In this paper, we present the system design and Web-based client-server model for computer-assisted bone age assessment and our initial implementation of the digital atlas database.
Parra-Cabrera, Cesar; Achille, Clement; Kuhn, Simon; Ameloot, Rob
2018-01-02
Computer-aided fabrication technologies combined with simulation and data processing approaches are changing our way of manufacturing and designing functional objects. Also in the field of catalytic technology and chemical engineering the impact of additive manufacturing, also referred to as 3D printing, is steadily increasing thanks to a rapidly decreasing equipment threshold. Although still in an early stage, the rapid and seamless transition between digital data and physical objects enabled by these fabrication tools will benefit both research and manufacture of reactors and structured catalysts. Additive manufacturing closes the gap between theory and experiment, by enabling accurate fabrication of geometries optimized through computational fluid dynamics and the experimental evaluation of their properties. This review highlights the research using 3D printing and computational modeling as digital tools for the design and fabrication of reactors and structured catalysts. The goal of this contribution is to stimulate interactions at the crossroads of chemistry and materials science on the one hand and digital fabrication and computational modeling on the other.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Satake, Shin-ichi; Kanamori, Hiroyuki; Kunugi, Tomoaki
2007-02-01
We have developed a parallel algorithm for microdigital-holographic particle-tracking velocimetry. The algorithm is used in (1) numerical reconstruction of a particle image computer using a digital hologram, and (2) searching for particles. The numerical reconstruction from the digital hologram makes use of the Fresnel diffraction equation and the FFT (fast Fourier transform),whereas the particle search algorithm looks for local maximum graduation in a reconstruction field represented by a 3D matrix. To achieve high performance computing for both calculations (reconstruction and particle search), two memory partitions are allocated to the 3D matrix. In this matrix, the reconstruction part consists of horizontallymore » placed 2D memory partitions on the x-y plane for the FFT, whereas, the particle search part consists of vertically placed 2D memory partitions set along the z axes.Consequently, the scalability can be obtained for the proportion of processor elements,where the benchmarks are carried out for parallel computation by a SGI Altix machine.« less
MICROPROCESSOR-BASED DATA-ACQUISITION SYSTEM FOR A BOREHOLE RADAR.
Bradley, Jerry A.; Wright, David L.
1987-01-01
An efficient microprocessor-based system is described that permits real-time acquisition, stacking, and digital recording of data generated by a borehole radar system. Although the system digitizes, stacks, and records independently of a computer, it is interfaced to a desktop computer for program control over system parameters such as sampling interval, number of samples, number of times the data are stacked prior to recording on nine-track tape, and for graphics display of the digitized data. The data can be transferred to the desktop computer during recording, or it can be played back from a tape at a latter time. Using the desktop computer, the operator observes results while recording data and generates hard-copy graphics in the field. Thus, the radar operator can immediately evaluate the quality of data being obtained, modify system parameters, study the radar logs before leaving the field, and rerun borehole logs if necessary. The system has proven to be reliable in the field and has increased productivity both in the field and in the laboratory.
Tsai, Hsin-yi Sandy; Shillair, Ruth; Cotten, Shelia R.
2017-01-01
This study examines how older adults learn to use tablet computers. Learning to use new technologies can help older adults to be included in today’s digital society. However, learning to use new technologies is not always easy, especially for older adults. This study focuses on how older adults learn to use a specific technology, tablet computers, and the role that social support plays in this process. Data for this project are from 21 in-depth interviews with individuals who own tablet computers. We examine how older adults engage with tablet devices and increase their digital literacy. The findings suggest that, for older adults to start to use tablets, social support plays an important role. In addition, a key way that many participants report gaining expertise with the technology is through “playing around” with the tablets. Suggestions for how to help older adults learn to use new technologies are detailed. PMID:26491029
Tsai, Hsin-Yi Sandy; Shillair, Ruth; Cotten, Shelia R
2017-01-01
This study examines how older adults learn to use tablet computers. Learning to use new technologies can help older adults to be included in today's digital society. However, learning to use new technologies is not always easy, especially for older adults. This study focuses on how older adults learn to use a specific technology, tablet computers, and the role that social support plays in this process. Data for this project are from 21 in-depth interviews with individuals who own tablet computers. We examine how older adults engage with tablet devices and increase their digital literacy. The findings suggest that, for older adults to start to use tablets, social support plays an important role. In addition, a key way that many participants report gaining expertise with the technology is through "playing around" with the tablets. Suggestions for how to help older adults learn to use new technologies are detailed. © The Author(s) 2015.
1991-09-27
AD-A241 692 II I] II I11 ANNUAL REPORT VOLUME 1 PART 2 TASK 1: DIGITAL EMULATION TECHNOLOGY LABORATOIRY REPORT NO. AR-0142-91-001 September 27, 1991... DIGITAL EMULATION TECHNOLOGY LABORATORY Contract No. DASG60-89-C-0142 Sponsored By The United States Army ? trategic Defense Command COMPUTER...ANNUAL REPORT VOLUME 1 PART 2 TASK 1: DIGITAL EMULATION TECHNOLOGY LABORATORY September 27, 1991 Authors Thomas R. Collins and Stephen R. Wachtel
NASA Astrophysics Data System (ADS)
Wang, Bo
2018-04-01
Based on the digitized information and network, digital campus is an integration of teaching, management, science and research, life service and technology service, and it is one of the current mainstream construction form of campus function. This paper regarded the "mobile computing" core digital environment construction development as the background, explored the multiple management system technology content design and achievement of multimedia classrooms in digital campus and scientifically proved the technology superiority of management system.
15 CFR Supplement No. 1 to Part 746 - Examples of Luxury Goods
Code of Federal Regulations, 2010 CFR
2010-01-01
... (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS...) Personal digital assistants (PDAs) (3) Personal digital music players (4) Computer laptops (g...
28 CFR 75.7 - Exemption statement.
Code of Federal Regulations, 2011 CFR
2011-07-01
..., periodical, film, videotape, digitally- or computer-manipulated image, digital image, picture, or other... pubic area of any person, made before March 18, 2009; (3) The matter contains only some combination of...
28 CFR 75.7 - Exemption statement.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., periodical, film, videotape, digitally- or computer-manipulated image, digital image, picture, or other... pubic area of any person, made before March 18, 2009; (3) The matter contains only some combination of...
Digital processing of mesoscale analysis and space sensor data
NASA Technical Reports Server (NTRS)
Hickey, J. S.; Karitani, S.
1985-01-01
The mesoscale analysis and space sensor (MASS) data management and analysis system on the research computer system is presented. The MASS data base management and analysis system was implemented on the research computer system which provides a wide range of capabilities for processing and displaying large volumes of conventional and satellite derived meteorological data. The research computer system consists of three primary computers (HP-1000F, Harris/6, and Perkin-Elmer 3250), each of which performs a specific function according to its unique capabilities. The overall tasks performed concerning the software, data base management and display capabilities of the research computer system in terms of providing a very effective interactive research tool for the digital processing of mesoscale analysis and space sensor data is described.
Program for the analysis of time series. [by means of fast Fourier transform algorithm
NASA Technical Reports Server (NTRS)
Brown, T. J.; Brown, C. G.; Hardin, J. C.
1974-01-01
A digital computer program for the Fourier analysis of discrete time data is described. The program was designed to handle multiple channels of digitized data on general purpose computer systems. It is written, primarily, in a version of FORTRAN 2 currently in use on CDC 6000 series computers. Some small portions are written in CDC COMPASS, an assembler level code. However, functional descriptions of these portions are provided so that the program may be adapted for use on any facility possessing a FORTRAN compiler and random-access capability. Properly formatted digital data are windowed and analyzed by means of a fast Fourier transform algorithm to generate the following functions: (1) auto and/or cross power spectra, (2) autocorrelations and/or cross correlations, (3) Fourier coefficients, (4) coherence functions, (5) transfer functions, and (6) histograms.
NASA Technical Reports Server (NTRS)
1986-01-01
Digital Imaging is the computer processed numerical representation of physical images. Enhancement of images results in easier interpretation. Quantitative digital image analysis by Perceptive Scientific Instruments, locates objects within an image and measures them to extract quantitative information. Applications are CAT scanners, radiography, microscopy in medicine as well as various industrial and manufacturing uses. The PSICOM 327 performs all digital image analysis functions. It is based on Jet Propulsion Laboratory technology, is accurate and cost efficient.
Collaborative learning model inquiring based on digital game
NASA Astrophysics Data System (ADS)
Yuan, Jiugen; Xing, Ruonan
2012-04-01
With the development of computer education software, digital educational game has become an important part in our life, entertainment and education. Therefore how to make full use of digital game's teaching functions and educate through entertainment has become the focus of current research. The thesis make a connection between educational game and collaborative learning, the current popular teaching model, and concludes digital game-based collaborative learning model combined with teaching practice.
Quantum Cascade Laser Tuning by Digital Micromirror Array-controlled External Cavity
2014-01-01
P. Vujkovic-Cvijin, B. Gregor, A. C. Samuels, E. S. Roese, Quantum cascade laser tuning by digital micromirror array-controlled external cavity...REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Quantum cascade laser tuning by digital micromirror array-controlled...dimensional digital micromirror array (DMA) is described. The laser is tuned by modulating the reflectivity of DMA micromirror pixels under computer
Watermarking 3D Objects for Verification
1999-01-01
signal (audio/ image /video) pro- cessing and steganography fields, and even newer to the computer graphics community. Inherently, digital watermarking of...quality images , and digital video. The field of digital watermarking is relatively new, and many of its terms have not been well defined. Among the dif...ferent media types, watermarking of 2D still images is comparatively better studied. Inherently, digital water- marking of 3D objects remains a
Hybrid computer technique yields random signal probability distributions
NASA Technical Reports Server (NTRS)
Cameron, W. D.
1965-01-01
Hybrid computer determines the probability distributions of instantaneous and peak amplitudes of random signals. This combined digital and analog computer system reduces the errors and delays of manual data analysis.
Computers in Electrical Engineering Education at Virginia Polytechnic Institute.
ERIC Educational Resources Information Center
Bennett, A. Wayne
1982-01-01
Discusses use of computers in Electrical Engineering (EE) at Virginia Polytechnic Institute. Topics include: departmental background, level of computing power using large scale systems, mini and microcomputers, use of digital logic trainers and analog/hybrid computers, comments on integrating computers into EE curricula, and computer use in…
Marolf, Angela; Blaik, Margaret; Ackerman, Norman; Watson, Elizabeth; Gibson, Nicole; Thompson, Margret
2008-01-01
The role of digital imaging is increasing as these systems are becoming more affordable and accessible. Advantages of computed radiography compared with conventional film/screen combinations include improved contrast resolution and postprocessing capabilities. Computed radiography's spatial resolution is inferior to conventional radiography; however, this limitation is considered clinically insignificant. This study prospectively compared digital imaging and conventional radiography in detecting small volume pneumoperitoneum. Twenty cadaver dogs (15-30 kg) were injected with 0.25, 0.25, and 0.5 ml for 1 ml total of air intra-abdominally, and radiographed sequentially using computed and conventional radiographic technologies. Three radiologists independently evaluated the images, and receiver operating curve (ROC) analysis compared the two imaging modalities. There was no statistical difference between computed and conventional radiography in detecting free abdominal air, but overall computed radiography was relatively more sensitive based on ROC analysis. Computed radiographic images consistently and significantly demonstrated a minimal amount of 0.5 ml of free air based on ROC analysis. However, no minimal air amount was consistently or significantly detected with conventional film. Readers were more likely to detect free air on lateral computed images than the other projections, with no significant increased sensitivity between film/screen projections. Further studies are indicated to determine the differences or lack thereof between various digital imaging systems and conventional film/screen systems.
Silveira-Neto, Nicolau; Flores, Mateus Ericson; De Carli, João Paulo; Costa, Max Dória; Matos, Felipe de Souza; Paranhos, Luiz Renato; Linden, Maria Salete Sandini
2017-11-01
This research evaluated detail registration in peri-implant bone using two different cone beam computer tomography systems and a digital periapical radiograph. Three different image acquisition protocols were established for each cone beam computer tomography apparatus, and three clinical situations were simulated in an ex vivo fresh pig mandible: buccal bone defect, peri-implant bone defect, and bone contact. Data were subjected to two analyses: quantitative and qualitative. The quantitative analyses involved a comparison of real specimen measures using a digital caliper in three regions of the preserved buccal bone - A, B and E (control group) - to cone beam computer tomography images obtained with different protocols (kp1, kp2, kp3, ip1, ip2, and ip3). In the qualitative analyses, the ability to register peri-implant details via tomography and digital periapical radiography was verified, as indicated by twelve evaluators. Data were analyzed with ANOVA and Tukey's test (α=0.05). The quantitative assessment showed means statistically equal to those of the control group under the following conditions: buccal bone defect B and E with kp1 and ip1, peri-implant bone defect E with kp2 and kp3, and bone contact A with kp1, kp2, kp3, and ip2. Qualitatively, only bone contacts were significantly different among the assessments, and the p3 results differed from the p1 and p2 results. The other results were statistically equivalent. The registration of peri-implant details was influenced by the image acquisition protocol, although metal artifacts were produced in all situations. The evaluators preferred the Kodak 9000 3D cone beam computer tomography in most cases. The evaluators identified buccal bone defects better with cone beam computer tomography and identified peri-implant bone defects better with digital periapical radiography.
The 2nd Symposium on the Frontiers of Massively Parallel Computations
NASA Technical Reports Server (NTRS)
Mills, Ronnie (Editor)
1988-01-01
Programming languages, computer graphics, neural networks, massively parallel computers, SIMD architecture, algorithms, digital terrain models, sort computation, simulation of charged particle transport on the massively parallel processor and image processing are among the topics discussed.
ERIC Educational Resources Information Center
Ludlow, Barbara L.; Foshay, John B.; Duff, Michael C.
Video presentations of teaching episodes in home, school, and community settings and audio recordings of parents' and professionals' views can be important adjuncts to personnel preparation in special education. This paper describes instructional applications of digital media and outlines steps in producing audio and video segments. Digital audio…
Computer Says No: An Analysis of Three Digital Food Education Resources
ERIC Educational Resources Information Center
Gard, Michael; Enright, Eimear
2016-01-01
What kind of thing will food education become in digitised classrooms? Drawn from a broader research project concerned with the "e turn" in school health and physical education, this paper analyses three examples of digital food education (DEF). This is done by considering the role of digital technology in changing--or not…
NASA Technical Reports Server (NTRS)
Boorstyn, R. R.
1973-01-01
Research is reported dealing with problems of digital data transmission and computer communications networks. The results of four individual studies are presented which include: (1) signal processing with finite state machines, (2) signal parameter estimation from discrete-time observations, (3) digital filtering for radar signal processing applications, and (4) multiple server queues where all servers are not identical.
Colloquium: Digital Technologies--Help or Hindrance for the Humanities?
ERIC Educational Resources Information Center
Barker, Elton; Bissell, Chris; Hardwick, Lorna; Jones, Allan; Ridge, Mia; Wolffe, John
2012-01-01
This article offers reflections arising from a recent colloquium at the Open University on the implications of the development of digital humanities for research in arts disciplines, and also for their interactions with computing and technology. Particular issues explored include the ways in which the digital turn in humanities research is also a…
Digital Learning: Meeting the Challenges and Embracing the Opportunities for Teachers. Issue Brief
ERIC Educational Resources Information Center
Collier, Denise; Burkholder, Karla; Branum, Tabitha
2013-01-01
Today's students are often called "digital-age learners"--reflecting their technological savvy and free-agent approach to learning. With their iPods, iPhones, computer games, social media pages, and text messaging, these digital-age students have access to resources and knowledge beyond traditional school structures and practices. These…
Digital Video for Fostering Self-Reflection in an ePortfolio Environment
ERIC Educational Resources Information Center
Cheng, Gary; Chau, Juliana
2009-01-01
The ability to self-reflect is widely recognized as a desirable learner attribute that can induce deep learning. Advances in computer-mediated communication technologies have led to intense interest in higher education in exploring the potential of digital tools, particularly digital video, for fostering self-reflection. While there are reports…
ERIC Educational Resources Information Center
Williamson, Ronald
2011-01-01
A "screenager" is a slang term used to describe teenagers who spend lots of time in front of digital screens (iPods, iPads, computers, other digital devices) (Webpodedia, 2011). The term is also used to describe the digital generation, students who are skilled at using technology to learn and communicate (Scherer, 2011). Given their comfort with…
Comparing Online to Face-To-Face Delivery of Undergraduate Digital Circuits Content
ERIC Educational Resources Information Center
LaMeres, Brock J.; Plumb, Carolyn
2014-01-01
This paper presents a comparison of online to traditional face-to-face delivery of undergraduate digital systems material. Two specific components of digital content were compared and evaluated: a sophomore logic circuits course with no laboratory, and a microprocessor laboratory component of a junior-level computer systems course. For each of…
Digital Literacy Practices among Youth Populations: A Review of the Literature
ERIC Educational Resources Information Center
Blummer, Barbara
2008-01-01
Digital literacy includes a range of abilities from basic computing skills to the creation of multimodal texts. This literature review examines eleven articles that track the digital literacy practices of youth populations or individuals between the ages of 12 and 17. It describes the practices of these individuals through three perspectives,…
The Use of Digitized Images in Developing Software for Young Children.
ERIC Educational Resources Information Center
Wright, June L.
1992-01-01
Parents and children interacted with computer-based representations of a park, one with animated picture graphics and one with digitized full motion video. Children who interacted with the digitized representation replayed the program more and showed a stronger cognitive focus on the representation than did the other children. (LB)
Cooperative Development of the Digital Library: Identifying and Working with Potential Partners.
ERIC Educational Resources Information Center
Poland, Jean
In a university environment, the library can benefit from interest in the digital future on the part of other concerned groups. Computer science departments are natural partners in the development of digital libraries. Professional societies, for-profit companies, and foundations are also potential sources of support. Cornell University Library…
Designing Computer-Based Learning Contents: Influence of Digital Zoom on Attention
ERIC Educational Resources Information Center
Glaser, Manuela; Lengyel, Dominik; Toulouse, Catherine; Schwan, Stephan
2017-01-01
In the present study, we investigated the role of digital zoom as a tool for directing attention while looking at visual learning material. In particular, we analyzed whether minimal digital zoom functions similarly to a rhetorical device by cueing mental zooming of attention accordingly. Participants were presented either static film clips, film…
Young Children's Learning with Digital Media
ERIC Educational Resources Information Center
Lieberman, Debra A.; Bates, Cynthia H.; So, Jiyeon
2009-01-01
This article reviews a selection of studies on digital media and learning for young children ages 3 to 6. The range of digital media for this age group is growing and includes computer-delivered and online activities; console video games; handheld media, occasionally with GPS or an accelerometer, in cell phones and other wireless mobile devices;…
Developing Competencies by Playing Digital Sports-Games
ERIC Educational Resources Information Center
Kretschmann, Rolf
2010-01-01
The idea of digital game-based learning (DGBL) is that students (or players) learn something by playing a computer or video game and that an educator can employ digital games to assist and boost both formal and informal learning. There is game software that is not specifically produced for educational use but which is nonetheless regularly…
Digital simulation of hybrid loop operation in RFI backgrounds.
NASA Technical Reports Server (NTRS)
Ziemer, R. E.; Nelson, D. R.
1972-01-01
A digital computer model for Monte-Carlo simulation of an imperfect second-order hybrid phase-locked loop (PLL) operating in radio-frequency interference (RFI) and Gaussian noise backgrounds has been developed. Characterization of hybrid loop performance in terms of cycle slipping statistics and phase error variance, through computer simulation, indicates that the hybrid loop has desirable performance characteristics in RFI backgrounds over the conventional PLL or the costas loop.
Subpicosecond Optical Digital Computation Using Conjugate Parametric Generators
1989-03-31
Using Phase Conjugate Farametric Generators ..... 12. PERSONAL AUTHOR(S) Alfano, Robert- Eichmann . George; Dorsinville. Roger! Li. Yao 13a. TYPE OF...conjugation-based optical residue arithmetic processor," Y. Li, G. Eichmann , R. Dorsinville, and R. R. Alfano, Opt. Lett. 13, (1988). [2] "Parallel ultrafast...optical digital and symbolic computation via optical phase conjugation," Y. Li, G. Eichmann , R. Dorsinville, Appl. Opt. 27, 2025 (1988). [3
98. View of IBM digital computer model 7090 magnet core ...
98. View of IBM digital computer model 7090 magnet core installation. ITT Artic Services, Inc., Official photograph BMEWS Site II, Clear, AK, by unknown photographer, 17 September 1965. BMEWS, clear as negative no. A-6606. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK
Information collection and processing of dam distortion in digital reservoir system
NASA Astrophysics Data System (ADS)
Liang, Yong; Zhang, Chengming; Li, Yanling; Wu, Qiulan; Ge, Pingju
2007-06-01
The "digital reservoir" is usually understood as describing the whole reservoir with digital information technology to make it serve the human existence and development furthest. Strictly speaking, the "digital reservoir" is referred to describing vast information of the reservoir in different dimension and space-time by RS, GPS, GIS, telemetry, remote-control and virtual reality technology based on computer, multi-media, large-scale memory and wide-band networks technology for the human existence, development and daily work, life and entertainment. The core of "digital reservoir" is to realize the intelligence and visibility of vast information of the reservoir through computers and networks. The dam is main building of reservoir, whose safety concerns reservoir and people's safety. Safety monitoring is important way guaranteeing the dam's safety, which controls the dam's running through collecting the dam's information concerned and developing trend. Safety monitoring of the dam is the process from collection and processing of initial safety information to forming safety concept in the brain. The paper mainly researches information collection and processing of the dam by digital means.
The digital implementation of control compensators: The coefficient wordlength issue
NASA Technical Reports Server (NTRS)
Moroney, P.; Willsky, A. S.; Houpt, P. K.
1979-01-01
There exists a number of mathematical procedures for designing discrete-time compensators. However, the digital implementation of these designs, with a microprocessor for example, has not received nearly as thorough an investigation. The finite-precision nature of the digital hardware makes it necessary to choose an algorithm (computational structure) that will perform 'well-enough' with regard to the initial objectives of the design. This paper describes a procedure for estimating the required fixed-point coefficient wordlength for any given computational structure for the implementation of a single-input single-output LOG design. The results are compared to the actual number of bits necessary to achieve a specified performance index.
Galloway, Joel M.; Vecchia, Aldo V.
2014-01-01
Modeled sulfate concentrations generally were highest (greater than 750 milligrams per liter) in basins in western North Dakota and lowest (less than 250 milligrams per liter) in basins in the upper Sheyenne River and upper James River. Area-weighted means for the basin characteristics also were computed for 10-digit and 8-digit hydrologic units for streams in North Dakota and modeled sulfate concentrations were computed from the characteristics. The resulting distribution of modeled sulfate concentrations was similar to the distribution of estimates for the 12-digit hydrologic units, but less variable because the basin characteristics were averaged over larger areas.
Digital Image Correlation Engine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Turner, Dan; Crozier, Paul; Reu, Phil
DICe is an open source digital image correlation (DIC) tool intended for use as a module in an external application or as a standalone analysis code. It's primary capability is computing full-field displacements and strains from sequences of digital These images are typically of a material sample undergoing a materials characterization experiment, but DICe is also useful for other applications (for example, trajectory tracking). DICe is machine portable (Windows, Linux and Mac) and can be effectively deployed on a high performance computing platform. Capabilities from DICe can be invoked through a library interface, via source code integration of DICe classesmore » or through a graphical user interface.« less
Computerized digital dermoscopy.
Gewirtzman, A J; Braun, R P
2003-01-01
Within the past 15 years, dermoscopy has become a widely used non-invasive technique for physicians to better visualize pigmented lesions. Dermoscopy has helped trained physicians to better diagnose pigmented lesions. Now, the digital revolution is beginning to enhance standard dermoscopic procedures. Using digital dermoscopy, physicians are better able to document pigmented lesions for patient follow-up and to get second opinions, either through teledermoscopy with an expert colleague or by using computer-assisted diagnosis. As the market for digital dermoscopy products begins to grow, so do the number of decisions physicians need to make when choosing a system to fit their needs. The current market for digital dermoscopy includes two varieties of relatively simple and cheap attachments which can convert a consumer digital camera into a digital dermoscope. A coupling adapter acts as a fastener between the camera and an ordinary dermoscope, whereas a dermoscopy attachment includes the dermoscope optics and light source and can be attached directly to the camera. Other options for digital dermoscopy include complete dermoscopy systems that use a hand-held video camera linked directly to a computer. These systems differ from each other in whether or not they are calibrated as well as the quality of the camera and software interface. Another option in digital skin imaging involves spectral analysis rather than dermoscopy. This article serves as a guide to the current systems available and their capabilities.
Evolving Digital Ecological Networks
Wagner, Aaron P.; Ofria, Charles
2013-01-01
“It is hard to realize that the living world as we know it is just one among many possibilities” [1]. Evolving digital ecological networks are webs of interacting, self-replicating, and evolving computer programs (i.e., digital organisms) that experience the same major ecological interactions as biological organisms (e.g., competition, predation, parasitism, and mutualism). Despite being computational, these programs evolve quickly in an open-ended way, and starting from only one or two ancestral organisms, the formation of ecological networks can be observed in real-time by tracking interactions between the constantly evolving organism phenotypes. These phenotypes may be defined by combinations of logical computations (hereafter tasks) that digital organisms perform and by expressed behaviors that have evolved. The types and outcomes of interactions between phenotypes are determined by task overlap for logic-defined phenotypes and by responses to encounters in the case of behavioral phenotypes. Biologists use these evolving networks to study active and fundamental topics within evolutionary ecology (e.g., the extent to which the architecture of multispecies networks shape coevolutionary outcomes, and the processes involved). PMID:23533370
Comparative analysis of autofocus functions in digital in-line phase-shifting holography.
Fonseca, Elsa S R; Fiadeiro, Paulo T; Pereira, Manuela; Pinheiro, António
2016-09-20
Numerical reconstruction of digital holograms relies on a precise knowledge of the original object position. However, there are a number of relevant applications where this parameter is not known in advance and an efficient autofocusing method is required. This paper addresses the problem of finding optimal focusing methods for use in reconstruction of digital holograms of macroscopic amplitude and phase objects, using digital in-line phase-shifting holography in transmission mode. Fifteen autofocus measures, including spatial-, spectral-, and sparsity-based methods, were evaluated for both synthetic and experimental holograms. The Fresnel transform and the angular spectrum reconstruction methods were compared. Evaluation criteria included unimodality, accuracy, resolution, and computational cost. Autofocusing under angular spectrum propagation tends to perform better with respect to accuracy and unimodality criteria. Phase objects are, generally, more difficult to focus than amplitude objects. The normalized variance, the standard correlation, and the Tenenbaum gradient are the most reliable spatial-based metrics, combining computational efficiency with good accuracy and resolution. A good trade-off between focus performance and computational cost was found for the Fresnelet sparsity method.
NASA Technical Reports Server (NTRS)
Joyce, A. T.
1974-01-01
Significant progress has been made in the classification of surface conditions (land uses) with computer-implemented techniques based on the use of ERTS digital data and pattern recognition software. The supervised technique presently used at the NASA Earth Resources Laboratory is based on maximum likelihood ratioing with a digital table look-up approach to classification. After classification, colors are assigned to the various surface conditions (land uses) classified, and the color-coded classification is film recorded on either positive or negative 9 1/2 in. film at the scale desired. Prints of the film strips are then mosaicked and photographed to produce a land use map in the format desired. Computer extraction of statistical information is performed to show the extent of each surface condition (land use) within any given land unit that can be identified in the image. Evaluations of the product indicate that classification accuracy is well within the limits for use by land resource managers and administrators. Classifications performed with digital data acquired during different seasons indicate that the combination of two or more classifications offer even better accuracy.
Use of laser 3D surface digitizer in data collection and 3D modeling of anatomical structures
NASA Astrophysics Data System (ADS)
Tse, Kelly; Van Der Wall, Hans; Vu, Dzung H.
2006-02-01
A laser digitizer (Konica-Minolta Vivid 910) is used to obtain 3-dimensional surface scans of anatomical structures with a maximum resolution of 0.1mm. Placing the specimen on a turntable allows multiple scans allaround because the scanner only captures data from the portion facing its lens. A computer model is generated using 3D modeling software such as Geomagic. The 3D model can be manipulated on screen for repeated analysis of anatomical features, a useful capability when the specimens are rare or inaccessible (museum collection, fossils, imprints in rock formation.). As accurate measurements can be performed on the computer model, instead of taking measurements on actual specimens only at the archeological excavation site e.g., a variety of quantitative data can be later obtained on the computer model in the laboratory as new ideas come to mind. Our group had used a mechanical contact digitizer (Microscribe) for this purpose, but with the surface digitizer, we have been obtaining data sets more accurately and more quickly.
Teaching and Learning Physics in a 1:1 Laptop School
NASA Astrophysics Data System (ADS)
Zucker, Andrew A.; Hug, Sarah T.
2008-12-01
1:1 laptop programs, in which every student is provided with a personal computer to use during the school year, permit increased and routine use of powerful, user-friendly computer-based tools. Growing numbers of 1:1 programs are reshaping the roles of teachers and learners in science classrooms. At the Denver School of Science and Technology, a public charter high school where a large percentage of students come from low-income families, 1:1 laptops are used often by teachers and students. This article describes the school's use of laptops, the Internet, and related digital tools, especially for teaching and learning physics. The data are from teacher and student surveys, interviews, classroom observations, and document analyses. Physics students and teachers use an interactive digital textbook; Internet-based simulations (some developed by a Nobel Prize winner); word processors; digital drop boxes; email; formative electronic assessments; computer-based and stand-alone graphing calculators; probes and associated software; and digital video cameras to explore hypotheses, collaborate, engage in scientific inquiry, and to identify strengths and weaknesses of students' understanding of physics. Technology provides students at DSST with high-quality tools to explore scientific concepts and the experiences of teachers and students illustrate effective uses of digital technology for high school physics.
Soyama, Takeshi; Sakuhara, Yusuke; Kudo, Kohsuke; Abo, Daisuke; Wang, Jeff; Ito, Yoichi M; Hasegawa, Yu; Shirato, Hiroki
2016-07-01
This preliminary study compared ultrasonography-computed tomography (US-CT) fusion imaging and conventional ultrasonography (US) for accuracy and time required for target identification using a combination of real phantoms and sets of digitally modified computed tomography (CT) images (digital/real hybrid phantoms). In this randomized prospective study, 27 spheres visible on B-mode US were placed at depths of 3.5, 8.5, and 13.5 cm (nine spheres each). All 27 spheres were digitally erased from the CT images, and a radiopaque sphere was digitally placed at each of the 27 locations to create 27 different sets of CT images. Twenty clinicians were instructed to identify the sphere target using US alone and fusion imaging. The accuracy of target identification of the two methods was compared using McNemar's test. The mean time required for target identification and error distances were compared using paired t tests. At all three depths, target identification was more accurate and the mean time required for target identification was significantly less with US-CT fusion imaging than with US alone, and the mean error distances were also shorter with US-CT fusion imaging. US-CT fusion imaging was superior to US alone in terms of accurate and rapid identification of target lesions.
The impact of digital imaging in the field of cytopathology.
Pantanowitz, Liron; Hornish, Maryanne; Goulart, Robert A
2009-03-06
With the introduction of digital imaging, pathology is undergoing a digital transformation. In the field of cytology, digital images are being used for telecytology, automated screening of Pap test slides, training and education (e.g. online digital atlases), and proficiency testing. To date, there has been no systematic review on the impact of digital imaging on the practice of cytopathology. This article critically addresses the emerging role of computer-assisted screening and the application of digital imaging to the field of cytology, including telecytology, virtual microscopy, and the impact of online cytology resources. The role of novel diagnostic techniques like image cytometry is also reviewed.
Farahani, Navid; Post, Robert; Duboy, Jon; Ahmed, Ishtiaque; Kolowitz, Brian J; Krinchai, Teppituk; Monaco, Sara E; Fine, Jeffrey L; Hartman, Douglas J; Pantanowitz, Liron
2016-01-01
Digital slides obtained from whole slide imaging (WSI) platforms are typically viewed in two dimensions using desktop personal computer monitors or more recently on mobile devices. To the best of our knowledge, we are not aware of any studies viewing digital pathology slides in a virtual reality (VR) environment. VR technology enables users to be artificially immersed in and interact with a computer-simulated world. Oculus Rift is among the world's first consumer-targeted VR headsets, intended primarily for enhanced gaming. Our aim was to explore the use of the Oculus Rift for examining digital pathology slides in a VR environment. An Oculus Rift Development Kit 2 (DK2) was connected to a 64-bit computer running Virtual Desktop software. Glass slides from twenty randomly selected lymph node cases (ten with benign and ten malignant diagnoses) were digitized using a WSI scanner. Three pathologists reviewed these digital slides on a 27-inch 5K display and with the Oculus Rift after a 2-week washout period. Recorded endpoints included concordance of final diagnoses and time required to examine slides. The pathologists also rated their ease of navigation, image quality, and diagnostic confidence for both modalities. There was 90% diagnostic concordance when reviewing WSI using a 5K display and Oculus Rift. The time required to examine digital pathology slides on the 5K display averaged 39 s (range 10-120 s), compared to 62 s with the Oculus Rift (range 15-270 s). All pathologists confirmed that digital pathology slides were easily viewable in a VR environment. The ratings for image quality and diagnostic confidence were higher when using the 5K display. Using the Oculus Rift DK2 to view and navigate pathology whole slide images in a virtual environment is feasible for diagnostic purposes. However, image resolution using the Oculus Rift device was limited. Interactive VR technologies such as the Oculus Rift are novel tools that may be of use in digital pathology.
Digital optical computers at the optoelectronic computing systems center
NASA Technical Reports Server (NTRS)
Jordan, Harry F.
1991-01-01
The Digital Optical Computing Program within the National Science Foundation Engineering Research Center for Opto-electronic Computing Systems has as its specific goal research on optical computing architectures suitable for use at the highest possible speeds. The program can be targeted toward exploiting the time domain because other programs in the Center are pursuing research on parallel optical systems, exploiting optical interconnection and optical devices and materials. Using a general purpose computing architecture as the focus, we are developing design techniques, tools and architecture for operation at the speed of light limit. Experimental work is being done with the somewhat low speed components currently available but with architectures which will scale up in speed as faster devices are developed. The design algorithms and tools developed for a general purpose, stored program computer are being applied to other systems such as optimally controlled optical communication networks.
Method and system for redundancy management of distributed and recoverable digital control system
NASA Technical Reports Server (NTRS)
Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)
2012-01-01
A method and system for redundancy management is provided for a distributed and recoverable digital control system. The method uses unique redundancy management techniques to achieve recovery and restoration of redundant elements to full operation in an asynchronous environment. The system includes a first computing unit comprising a pair of redundant computational lanes for generating redundant control commands. One or more internal monitors detect data errors in the control commands, and provide a recovery trigger to the first computing unit. A second redundant computing unit provides the same features as the first computing unit. A first actuator control unit is configured to provide blending and monitoring of the control commands from the first and second computing units, and to provide a recovery trigger to each of the first and second computing units. A second actuator control unit provides the same features as the first actuator control unit.
Applications of a digital darkroom in the forensic laboratory
NASA Astrophysics Data System (ADS)
Bullard, Barry D.; Birge, Brian
1997-02-01
Through a joint agreement with the Indiana-Marion County Forensic Laboratory Services Agency, the Institute for Forensic Imaging conducted a pilot program to investigate crime lab applications of a digital darkroom. IFI installed and staffed a state-of-the-art digital darkroom in the photography laboratory of the Indianapolis-Marion County crime lab located at Indianapolis, Indiana. The darkroom consisted of several high resolution color digital cameras, image processing computer, dye sublimation continuous tone digital printers, and CD-ROM writer. This paper describes the use of the digital darkroom in several crime lab investigations conducted during the program.
ERIC Educational Resources Information Center
Taylor, Jack A.
1983-01-01
Peripheral components for music instruction include a music keyboard, a digital music synthesizer, and music listening devices. Computers can teach sight-singing, playing an instrument, dictation, and composition. Computer programs should be interactive with students. (KC)
Network-Physics(NP) Bec DIGITAL(#)-VULNERABILITY Versus Fault-Tolerant Analog
NASA Astrophysics Data System (ADS)
Alexander, G. K.; Hathaway, M.; Schmidt, H. E.; Siegel, E.
2011-03-01
Siegel[AMS Joint Mtg.(2002)-Abs.973-60-124] digits logarithmic-(Newcomb(1881)-Weyl(1914; 1916)-Benford(1938)-"NeWBe"/"OLDbe")-law algebraic-inversion to ONLY BEQS BEC:Quanta/Bosons= digits: Synthesis reveals EMP-like SEVERE VULNERABILITY of ONLY DIGITAL-networks(VS. FAULT-TOLERANT ANALOG INvulnerability) via Barabasi "Network-Physics" relative-``statics''(VS.dynamics-[Willinger-Alderson-Doyle(Not.AMS(5/09)]-]critique); (so called)"Quantum-computing is simple-arithmetic(sans division/ factorization); algorithmic-complexities: INtractibility/ UNdecidability/ INefficiency/NONcomputability / HARDNESS(so MIScalled) "noise"-induced-phase-transitions(NITS) ACCELERATION: Cook-Levin theorem Reducibility is Renormalization-(Semi)-Group fixed-points; number-Randomness DEFINITION via WHAT? Query(VS. Goldreich[Not.AMS(02)] How? mea culpa)can ONLY be MBCS "hot-plasma" versus digit-clumping NON-random BEC; Modular-arithmetic Congruences= Signal X Noise PRODUCTS = clock-model; NON-Shor[Physica A,341,586(04)] BEC logarithmic-law inversion factorization:Watkins number-thy. U stat.-phys.); P=/=NP TRIVIAL Proof: Euclid!!! [(So Miscalled) computational-complexity J-O obviation via geometry.
Method for acquiring, storing and analyzing crystal images
NASA Technical Reports Server (NTRS)
Gester, Thomas E. (Inventor); Rosenblum, William M. (Inventor); Christopher, Gayle K. (Inventor); Hamrick, David T. (Inventor); Delucas, Lawrence J. (Inventor); Tillotson, Brian (Inventor)
2003-01-01
A system utilizing a digital computer for acquiring, storing and evaluating crystal images. The system includes a video camera (12) which produces a digital output signal representative of a crystal specimen positioned within its focal window (16). The digitized output from the camera (12) is then stored on data storage media (32) together with other parameters inputted by a technician and relevant to the crystal specimen. Preferably, the digitized images are stored on removable media (32) while the parameters for different crystal specimens are maintained in a database (40) with indices to the digitized optical images on the other data storage media (32). Computer software is then utilized to identify not only the presence and number of crystals and the edges of the crystal specimens from the optical image, but to also rate the crystal specimens by various parameters, such as edge straightness, polygon formation, aspect ratio, surface clarity, crystal cracks and other defects or lack thereof, and other parameters relevant to the quality of the crystals.
A high-accuracy optical linear algebra processor for finite element applications
NASA Technical Reports Server (NTRS)
Casasent, D.; Taylor, B. K.
1984-01-01
Optical linear processors are computationally efficient computers for solving matrix-matrix and matrix-vector oriented problems. Optical system errors limit their dynamic range to 30-40 dB, which limits their accuray to 9-12 bits. Large problems, such as the finite element problem in structural mechanics (with tens or hundreds of thousands of variables) which can exploit the speed of optical processors, require the 32 bit accuracy obtainable from digital machines. To obtain this required 32 bit accuracy with an optical processor, the data can be digitally encoded, thereby reducing the dynamic range requirements of the optical system (i.e., decreasing the effect of optical errors on the data) while providing increased accuracy. This report describes a new digitally encoded optical linear algebra processor architecture for solving finite element and banded matrix-vector problems. A linear static plate bending case study is described which quantities the processor requirements. Multiplication by digital convolution is explained, and the digitally encoded optical processor architecture is advanced.
Apparatus for direct-to-digital spatially-heterodyned holography
Thomas, Clarence E.; Hanson, Gregory R.
2006-12-12
An apparatus operable to record a spatially low-frequency heterodyne hologram including spatially heterodyne fringes for Fourier analysis includes: a laser; a beamsplitter optically coupled to the laser; an object optically coupled to the beamsplitter; a focusing lens optically coupled to both the beamsplitter and the object; a digital recorder optically coupled to the focusing lens; and a computer that performs a Fourier transform, applies a digital filter, and performs an inverse Fourier transform. A reference beam and an object beam are focused by the focusing lens at a focal plane of the digital recorder to form a spatially low-frequency heterodyne hologram including spatially heterodyne fringes for Fourier analysis which is recorded by the digital recorder, and the computer transforms the recorded spatially low-frequency heterodyne hologram including spatially heterodyne fringes and shifts axes in Fourier space to sit on top of a heterodyne carrier frequency defined by an angle between the reference beam and the object beam and cuts off signals around an original origin before performing the inverse Fourier transform.
Digital Mammography with a Mosaic of CCD-Arrays
NASA Technical Reports Server (NTRS)
Jalink, Antony, Jr. (Inventor); McAdoo, James A. (Inventor)
1996-01-01
The present invention relates generally to a mammography device and method and more particularly to a novel digital mammography device and method to detect microcalcifications of precancerous tissue. A digital mammography device uses a mosaic of electronic digital imaging arrays to scan an x-ray image. The mosaic of arrays is repositioned several times to expose different portions of the image, until the entire image is scanned. The data generated by the arrays during each exposure is stored in a computer. After the final exposure, the computer combines data of the several partial images to produce a composite of the original x-ray image. An aperture plate is used to reduce scatter and the overall exposure of the patient to x-rays. The novelty of this invention is that it provides a digital mammography device with large field coverage, high spatial resolution, scatter rejection, excellent contrast characteristics and lesion detectability under clinical conditions. This device also shields the patient from excessive radiation, can detect extremely small calcifications and allows manipulation and storage of the image.
Lanis, Alejandro; Álvarez Del Canto, Orlando
2015-01-01
The incorporation of virtual engineering into dentistry and the digitization of information are providing new perspectives and innovative alternatives for dental treatment modalities. The use of digital surface scanners with surgical planning software allows for the combination of the radiographic, prosthetic, surgical, and laboratory fields under a common virtual scenario, permitting complete digital treatment planning. In this article, the authors present a clinical case in which a guided implant surgery was performed based on a complete digital surgical plan combining the information from a cone beam computed tomography scan and the virtual simulation obtained from the 3Shape TRIOS intraoral surface scanner. The information was imported to and combined in the 3Shape Implant Studio software for guided implant surgery planning. A surgical guide was obtained by a 3D printer, and the surgical procedure was done using the Biohorizons Guided Surgery Kit and its protocol.
Ammann, Alexander
2016-01-01
"Digitality" (as opposed to "digitalization"--the conversion from the analog domain to the digital domain) will open up a whole new world that does not originate from the analog world. Contemporary research in the field of neural concepts and neuromorphic computing systems will lead to convergences between the world of digitality and the world of neuronality, giving the theme "Knowledge and Culture" a new meaning. The simulation of virtual multidimensional and contextual spaces will transform the transfer of knowledge from a uni- and bidirectional process into an interactive experience. We will learn to learn in a ubiquitous computing environment and will abandon conventional curriculum organization principles. The adaptation of individualized ontologies will result in the emergence of a new world of knowledge in which knowledge evolves from a cultural heritage into a commodity.
Digital image processing of bone - Problems and potentials
NASA Technical Reports Server (NTRS)
Morey, E. R.; Wronski, T. J.
1980-01-01
The development of a digital image processing system for bone histomorphometry and fluorescent marker monitoring is discussed. The system in question is capable of making measurements of UV or light microscope features on a video screen with either video or computer-generated images, and comprises a microscope, low-light-level video camera, video digitizer and display terminal, color monitor, and PDP 11/34 computer. Capabilities demonstrated in the analysis of an undecalcified rat tibia include the measurement of perimeter and total bone area, and the generation of microscope images, false color images, digitized images and contoured images for further analysis. Software development will be based on an existing software library, specifically the mini-VICAR system developed at JPL. It is noted that the potentials of the system in terms of speed and reliability far exceed any problems associated with hardware and software development.
Accurate computation of gravitational field of a tesseroid
NASA Astrophysics Data System (ADS)
Fukushima, Toshio
2018-02-01
We developed an accurate method to compute the gravitational field of a tesseroid. The method numerically integrates a surface integral representation of the gravitational potential of the tesseroid by conditionally splitting its line integration intervals and by using the double exponential quadrature rule. Then, it evaluates the gravitational acceleration vector and the gravity gradient tensor by numerically differentiating the numerically integrated potential. The numerical differentiation is conducted by appropriately switching the central and the single-sided second-order difference formulas with a suitable choice of the test argument displacement. If necessary, the new method is extended to the case of a general tesseroid with the variable density profile, the variable surface height functions, and/or the variable intervals in longitude or in latitude. The new method is capable of computing the gravitational field of the tesseroid independently on the location of the evaluation point, namely whether outside, near the surface of, on the surface of, or inside the tesseroid. The achievable precision is 14-15 digits for the potential, 9-11 digits for the acceleration vector, and 6-8 digits for the gradient tensor in the double precision environment. The correct digits are roughly doubled if employing the quadruple precision computation. The new method provides a reliable procedure to compute the topographic gravitational field, especially that near, on, and below the surface. Also, it could potentially serve as a sure reference to complement and elaborate the existing approaches using the Gauss-Legendre quadrature or other standard methods of numerical integration.
Digital Model of Railway Electric Traction Lines
NASA Astrophysics Data System (ADS)
Garg, Rachana; Mahajan, Priya; Kumar, Parmod
2017-08-01
The characteristic impedance and propagation constant define the behavior of signal propagation over the transmission lines. The digital model for railway traction lines which includes railway tracks is developed, using curve fitting technique in MATLAB. The sensitivity of this model has been computed with respect to frequency. The digital sensitivity values are compared with the values of analog sensitivity. The developed model is useful for digital protection, integrated operation, control and planning of the system.
Massively parallel information processing systems for space applications
NASA Technical Reports Server (NTRS)
Schaefer, D. H.
1979-01-01
NASA is developing massively parallel systems for ultra high speed processing of digital image data collected by satellite borne instrumentation. Such systems contain thousands of processing elements. Work is underway on the design and fabrication of the 'Massively Parallel Processor', a ground computer containing 16,384 processing elements arranged in a 128 x 128 array. This computer uses existing technology. Advanced work includes the development of semiconductor chips containing thousands of feedthrough paths. Massively parallel image analog to digital conversion technology is also being developed. The goal is to provide compact computers suitable for real-time onboard processing of images.
Monitoring land degradation in southern Tunisia: A test of LANDSAT imagery and digital data
NASA Technical Reports Server (NTRS)
Hellden, U.; Stern, M.
1980-01-01
The possible use of LANDSAT imagery and digital data for monitoring desertification indicators in Tunisia was studied. Field data were sampled in Tunisia for estimation of mapping accuracy in maps generated through interpretation of LANDSAT false color composites and processing of LANDSAT computer compatible tapes respectively. Temporal change studies were carried out through geometric registration of computer classified windows from 1972 to classified data from 1979. Indications on land degradation were noted in some areas. No important differences, concerning results, between the interpretation approach and the computer processing approach were found.
Digital image processing using parallel computing based on CUDA technology
NASA Astrophysics Data System (ADS)
Skirnevskiy, I. P.; Pustovit, A. V.; Abdrashitova, M. O.
2017-01-01
This article describes expediency of using a graphics processing unit (GPU) in big data processing in the context of digital images processing. It provides a short description of a parallel computing technology and its usage in different areas, definition of the image noise and a brief overview of some noise removal algorithms. It also describes some basic requirements that should be met by certain noise removal algorithm in the projection to computer tomography. It provides comparison of the performance with and without using GPU as well as with different percentage of using CPU and GPU.
Animations, games, and virtual reality for the Jing-Hang Grand Canal.
Chen, Wenzhi; Zhang, Mingmin; Pan, Zhigeng; Liu, Gengdai; Shen, Huaqing; Chen, Shengnan; Liu, Yong
2010-01-01
Digital heritage, an effective method to preserve and present natural and cultural heritage, is engaging many heritage preservation specialists and computer scientists. In particular, computer graphics researchers have become involved, and digital heritage has employed many CG techniques. For example, Daniel Pletinckx and his colleagues employed VR in a real museum at Ename, Belgium, and Zhigeng Pan and his colleagues applied it to construct a virtual Olympics museum. Soo-Chang Pei and his colleagues focused on restoring ancient Chinese paintings. Here, we describe how we've applied animations, computer games, and VR to China's famous Jing-Hang Grand Canal.
Robust Routing Protocol For Digital Messages
NASA Technical Reports Server (NTRS)
Marvit, Maclen
1994-01-01
Refinement of ditigal-message-routing protocol increases fault tolerance of polled networks. AbNET-3 is latest of generic AbNET protocols for transmission of messages among computing nodes. AbNET concept described in "Multiple-Ring Digital Communication Network" (NPO-18133). Specifically aimed at increasing fault tolerance of network in broadcast mode, in which one node broadcasts message to and receives responses from all other nodes. Communication in network of computers maintained even when links fail.
A statistical package for computing time and frequency domain analysis
NASA Technical Reports Server (NTRS)
Brownlow, J.
1978-01-01
The spectrum analysis (SPA) program is a general purpose digital computer program designed to aid in data analysis. The program does time and frequency domain statistical analyses as well as some preanalysis data preparation. The capabilities of the SPA program include linear trend removal and/or digital filtering of data, plotting and/or listing of both filtered and unfiltered data, time domain statistical characterization of data, and frequency domain statistical characterization of data.
97. View of International Business Machine (IBM) digital computer model ...
97. View of International Business Machine (IBM) digital computer model 7090 magnetic core installation, international telephone and telegraph (ITT) Artic Services Inc., Official photograph BMEWS site II, Clear, AK, by unknown photographer, 17 September 1965, BMEWS, clear as negative no. A-6604. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK
A digital computer simulation and study of a direct-energy-transfer power-conditioning system
NASA Technical Reports Server (NTRS)
Burns, W. W., III; Owen, H. A., Jr.; Wilson, T. G.; Rodriguez, G. E.; Paulkovich, J.
1974-01-01
A digital computer simulation technique, which can be used to study such composite power-conditioning systems, was applied to a spacecraft direct-energy-transfer power-processing system. The results obtained duplicate actual system performance with considerable accuracy. The validity of the approach and its usefulness in studying various aspects of system performance such as steady-state characteristics and transient responses to severely varying operating conditions are demonstrated experimentally.
NASA Astrophysics Data System (ADS)
Meurant, Robert C.
Second Language (L2) Digital Literacy is of emerging importance within English as a Foreign Language (EFL) in Korea, and will evolve to become regarded as the most critical component of overall L2 English Literacy. Computer-based Internet-hosted Learning Management Systems (LMS), such as the popular open-source Moodle, are rapidly being adopted worldwide for distance education, and are also being applied to blended (hybrid) education. In EFL Education, they have a special potential: by setting the LMS to force English to be used exclusively throughout a course website, the meta-language can be made the target L2 language. Of necessity, students develop the ability to use English to navigate the Internet, access and contribute to online resources, and engage in computer-mediated communication. Through such pragmatic engagement with English, students significantly develop their L2 Digital Literacy.
Accuracy and Landmark Error Calculation Using Cone-Beam Computed Tomography–Generated Cephalograms
Grauer, Dan; Cevidanes, Lucia S. H.; Styner, Martin A.; Heulfe, Inam; Harmon, Eric T.; Zhu, Hongtu; Proffit, William R.
2010-01-01
Objective To evaluate systematic differences in landmark position between cone-beam computed tomography (CBCT)–generated cephalograms and conventional digital cephalograms and to estimate how much variability should be taken into account when both modalities are used within the same longitudinal study. Materials and Methods Landmarks on homologous cone-beam computed tomographic–generated cephalograms and conventional digital cephalograms of 46 patients were digitized, registered, and compared via the Hotelling T2 test. Results There were no systematic differences between modalities in the position of most landmarks. Three landmarks showed statistically significant differences but did not reach clinical significance. A method for error calculation while combining both modalities in the same individual is presented. Conclusion In a longitudinal follow-up for assessment of treatment outcomes and growth of one individual, the error due to the combination of the two modalities might be larger than previously estimated. PMID:19905853
Ventura Ferreira, Nuno; Leal, Nuno; Correia Sá, Inês; Reis, Ana; Marques, Marisa
2014-01-01
The fabrication of digital prostheses has acquired growing importance not only for the possibility for the patient to overcome psychosocial trauma but also to promote grip functionality. An application method of three dimensional-computer-aided design technologies for the production of passive prostheses is presented by means of a fifth finger amputee clinical case following bilateral hand replantation.Three-dimensional-computerized tomography was used for the collection of anthropometric images of the hands. Computer-aided design techniques were used to develop the digital file-based prosthesis from the reconstruction images by inversion and superimposing the contra-lateral finger images. The rapid prototyping manufacturing method was used for the production of a silicone bandage prosthesis prototype. This approach replaces the traditional manual method by a virtual method that is basis for the optimization of a high speed, accurate and innovative process.
Seomun, GyeongAe; Kim, YoungHwan; Lee, Jung-Ah; Jeong, KwangHoon; Park, Seon-A; Kim, Miran; Noh, Wonjung
2014-04-01
To better understand environmental electromagnetic wave exposure during the use of digital textbooks by elementary school students, we measured numeric values of the electromagnetic fields produced by tablet personal computers (TPCs). Specifically, we examined the distribution of the electromagnetic waves for various students' seating positions in an elementary school that uses digital textbooks. Electric and magnetic fields from TPCs were measured using the HI-3603 Visual Display Terminal/ Very Low Frequency (VDT/VLF) radiation measurement system. Electromagnetic field values from TPCs measured at a student's seat and at a teacher's computer were deemed not harmful to health. However, electromagnetic field values varied based on the distance between students, other electronic devices such as a desktop computers, and student posture while using a TPC. Based on these results, it is necessary to guide students to observe proper posture and to arrange seats at an appropriate distance in the classroom.
[Profile, competencies and digital fluency of nurses in the Professional Improvement Program].
Tanabe, Lyvia Pini; Kobayashi, Rika Miyahara
2013-08-01
A descriptive exploratory study conducted in the city of São Paulo, which aimed to identify the profile, competencies and digital fluency of nurses in the Professional Improvement Program in handling technology at work. The population, composed by 60 nurses in the program, answered a questionnaire with data about profile, digital fluency and professional competencies. The participants were found to be: 95.0% female, 61.7% between 23 and 25 years old, 75.0% from public schools, 58.3% enrolled in cardiovascular nursing, 98.3% had contact with computing resources during graduation, 100.0% had a computer at home, 86.7% accessed the internet daily, 96.7% used Messenger and 58.3% had an intermediate level of knowledge and skill in computing. Professional competencies required for technology management referred to knowing how to be innovative, creative, and updated to identify and manage software and to use technological resources.
Fundamental Concepts of Digital Image Processing
DOE R&D Accomplishments Database
Twogood, R. E.
1983-03-01
The field of a digital-image processing has experienced dramatic growth and increasingly widespread applicability in recent years. Fortunately, advances in computer technology have kept pace with the rapid growth in volume of image data in these and other applications. Digital image processing has become economical in many fields of research and in industrial and military applications. While each application has requirements unique from the others, all are concerned with faster, cheaper, more accurate, and more extensive computation. The trend is toward real-time and interactive operations, where the user of the system obtains preliminary results within a short enough time that the next decision can be made by the human processor without loss of concentration on the task at hand. An example of this is the obtaining of two-dimensional (2-D) computer-aided tomography (CAT) images. A medical decision might be made while the patient is still under observation rather than days later.
ERIC Educational Resources Information Center
Wise, Stuart; Greenwood, Janinka; Davis, Niki
2011-01-01
The music industry in the 21st century uses digital technology in a wide range of applications including performance, composition and in recording and publishing. Much of this digital technology is freely available via downloads from the internet, as part of software included with computers when they are purchased and via applications that are…
Digital Game-Based Learning for K-12 Mathematics Education: A Meta-Analysis
ERIC Educational Resources Information Center
Byun, JaeHwan; Joung, Eunmi
2018-01-01
Digital games (e.g., video games or computer games) have been reported as an effective educational method that can improve students' motivation and performance in mathematics education. This meta-analysis study (a) investigates the current trend of digital game-based learning (DGBL) by reviewing the research studies on the use of DGBL for…
Taking Digital Creativity to the Art Classroom: Mystery Box Swap
ERIC Educational Resources Information Center
Shin, Ryan
2010-01-01
Today's students are the first generation to grow up with computers, cell-phones, video games, music and video players, and other digital technologies. As "digital natives", a new term coined by Prensky (2001), they spend more time reading text messaging lines than lines from books, and they spend more time on Facebook than putting their energies…
Academics' Attitudes toward Using Digital Games for Learning & Teaching in Malaysia
ERIC Educational Resources Information Center
Noraddin, Enas Mohamed; Kian, Neo Tse
2014-01-01
Digital (or computer) games have been extremely attractive to gamers of all ages, especially the young ones. They spend much time playing such games for pleasure and entertainment. Harnessing digital games for education has been attempted in some advanced countries where teachers seemed to be receptive to the idea. In Malaysia no major study has…
A Computer-Assisted Learning Model Based on the Digital Game Exponential Reward System
ERIC Educational Resources Information Center
Moon, Man-Ki; Jahng, Surng-Gahb; Kim, Tae-Yong
2011-01-01
The aim of this research was to construct a motivational model which would stimulate voluntary and proactive learning using digital game methods offering players more freedom and control. The theoretical framework of this research lays the foundation for a pedagogical learning model based on digital games. We analyzed the game reward system, which…
ERIC Educational Resources Information Center
Prosser, Andrew
2014-01-01
Digital storytelling is already used extensively in language education. Web documentaries, particularly in terms of design and narrative structure, provide an extension of the digital storytelling concept, specifically in terms of increased interactivity. Using a model of interactive, non-linear storytelling, originally derived from computer game…
Digital Troposcatter Performance Model
1983-12-01
Dist Speia DIIBUTON STATEMR AO Approved tot public relemg ** - DistributionUnlimited __________ Communications. Control and Information Systems ...for digital troposcatter communication system design is described. Propagation and modem performance *are modeled. These include Path Loss and RSL...designing digital troposcatter systems . A User’s Manual Report discusses the use of the computer program TROPO. The description of the structure and logical
NASA Technical Reports Server (NTRS)
Bendura, R. J.; Renfroe, P. G.
1974-01-01
A detailed discussion of the application of a previously method to determine vehicle flight attitude using a single camera onboard the vehicle is presented with emphasis on the digital computer program format and data reduction techniques. Application requirements include film and earth-related coordinates of at least two landmarks (or features), location of the flight vehicle with respect to the earth, and camera characteristics. Included in this report are a detailed discussion of the program input and output format, a computer program listing, a discussion of modifications made to the initial method, a step-by-step basic data reduction procedure, and several example applications. The computer program is written in FORTRAN 4 language for the Control Data 6000 series digital computer.
A computational model of selection by consequences.
McDowell, J J
2004-01-01
Darwinian selection by consequences was instantiated in a computational model that consisted of a repertoire of behaviors undergoing selection, reproduction, and mutation over many generations. The model in effect created a digital organism that emitted behavior continuously. The behavior of this digital organism was studied in three series of computational experiments that arranged reinforcement according to random-interval (RI) schedules. The quantitative features of the model were varied over wide ranges in these experiments, and many of the qualitative features of the model also were varied. The digital organism consistently showed a hyperbolic relation between response and reinforcement rates, and this hyperbolic description of the data was consistently better than the description provided by other, similar, function forms. In addition, the parameters of the hyperbola varied systematically with the quantitative, and some of the qualitative, properties of the model in ways that were consistent with findings from biological organisms. These results suggest that the material events responsible for an organism's responding on RI schedules are computationally equivalent to Darwinian selection by consequences. They also suggest that the computational model developed here is worth pursuing further as a possible dynamic account of behavior. PMID:15357512
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trease, Lynn L.; Trease, Harold E.; Fowler, John
2007-03-15
One of the critical steps toward performing computational biology simulations, using mesh based integration methods, is in using topologically faithful geometry derived from experimental digital image data as the basis for generating the computational meshes. Digital image data representations contain both the topology of the geometric features and experimental field data distributions. The geometric features that need to be captured from the digital image data are three-dimensional, therefore the process and tools we have developed work with volumetric image data represented as data-cubes. This allows us to take advantage of 2D curvature information during the segmentation and feature extraction process.more » The process is basically: 1) segmenting to isolate and enhance the contrast of the features that we wish to extract and reconstruct, 2) extracting the geometry of the features in an isosurfacing technique, and 3) building the computational mesh using the extracted feature geometry. “Quantitative” image reconstruction and feature extraction is done for the purpose of generating computational meshes, not just for producing graphics "screen" quality images. For example, the surface geometry that we extract must represent a closed water-tight surface.« less
The application of virtual reality systems as a support of digital manufacturing and logistics
NASA Astrophysics Data System (ADS)
Golda, G.; Kampa, A.; Paprocka, I.
2016-08-01
Modern trends in development of computer aided techniques are heading toward the integration of design competitive products and so-called "digital manufacturing and logistics", supported by computer simulation software. All phases of product lifecycle: starting from design of a new product, through planning and control of manufacturing, assembly, internal logistics and repairs, quality control, distribution to customers and after-sale service, up to its recycling or utilization should be aided and managed by advanced packages of product lifecycle management software. Important problems for providing the efficient flow of materials in supply chain management of whole product lifecycle, using computer simulation will be described on that paper. Authors will pay attention to the processes of acquiring relevant information and correct data, necessary for virtual modeling and computer simulation of integrated manufacturing and logistics systems. The article describes possibilities of use an applications of virtual reality software for modeling and simulation the production and logistics processes in enterprise in different aspects of product lifecycle management. The authors demonstrate effective method of creating computer simulations for digital manufacturing and logistics and show modeled and programmed examples and solutions. They pay attention to development trends and show options of the applications that go beyond enterprise.
Scalable Multiprocessor for High-Speed Computing in Space
NASA Technical Reports Server (NTRS)
Lux, James; Lang, Minh; Nishimoto, Kouji; Clark, Douglas; Stosic, Dorothy; Bachmann, Alex; Wilkinson, William; Steffke, Richard
2004-01-01
A report discusses the continuing development of a scalable multiprocessor computing system for hard real-time applications aboard a spacecraft. "Hard realtime applications" signifies applications, like real-time radar signal processing, in which the data to be processed are generated at "hundreds" of pulses per second, each pulse "requiring" millions of arithmetic operations. In these applications, the digital processors must be tightly integrated with analog instrumentation (e.g., radar equipment), and data input/output must be synchronized with analog instrumentation, controlled to within fractions of a microsecond. The scalable multiprocessor is a cluster of identical commercial-off-the-shelf generic DSP (digital-signal-processing) computers plus generic interface circuits, including analog-to-digital converters, all controlled by software. The processors are computers interconnected by high-speed serial links. Performance can be increased by adding hardware modules and correspondingly modifying the software. Work is distributed among the processors in a parallel or pipeline fashion by means of a flexible master/slave control and timing scheme. Each processor operates under its own local clock; synchronization is achieved by broadcasting master time signals to all the processors, which compute offsets between the master clock and their local clocks.
CILT2000: Ubiquitous Computing--Spanning the Digital Divide.
ERIC Educational Resources Information Center
Tinker, Robert; Vahey, Philip
2002-01-01
Discusses the role of ubiquitous and handheld computers in education. Summarizes the contributions of the Center for Innovative Learning Technologies (CILT) and describes the ubiquitous computing sessions at the CILT2000 Conference. (Author/YDS)
ERIC Educational Resources Information Center
Marty, Paul F.; Rayward, W. Boyd; Twidale, Michael B.
2003-01-01
Discusses museum informatics that studies how information science and technology affect the museum environment. Examines digital technology; information organization and access; digitization, personal computers, and the Internet; data sharing; standards; social impacts of new technologies; collaboration; consortia; multimedia exhibits; virtual…
NASA Astrophysics Data System (ADS)
DiSalvo, Elizabeth Betsy
The implementation of a learning environment for young African American males, called the Glitch Game Testers, was launched in 2009. The development of this program was based on formative work that looked at the contrasting use of digital games between young African American males and individuals who chose to become computer science majors. Through analysis of cultural values and digital game play practices, the program was designed to intertwine authentic game development practices and computer science learning. The resulting program employed 25 African American male high school students to test pre-release digital games full-time in the summer and part-time in the school year, with an hour of each day dedicated to learning introductory computer science. Outcomes for persisting in computer science education are remarkable; of the 16 participants who had graduated from high school as of 2012, 12 have gone on to school in computing-related majors. These outcomes, and the participants' enthusiasm for engaging in computing, are in sharp contrast to the crisis in African American male education and learning motivation. The research presented in this dissertation discusses the formative research that shaped the design of Glitch, the evaluation of the implementation of Glitch, and a theoretical investigation of the way in which participants navigated conflicting motivations in learning environments.
The graphic cell method: a new look at digitizing geologic maps
Hanley, J.T.
1982-01-01
The graphic cell method is an alternative method of digitizing areal geologic information. It involves a discrete-point sampling scheme in which the computer establishes a matrix of cells over the map. Each cell and the whole cell is assigned the identity or value of the geologic information that is recognized at its center. Cell size may be changed to suit the needs of the user. The computer program resolves the matrix and identifies potential errors such as multiple assignments. Input includes the digitized boundaries of each geologic formation. This method should eliminate a primary bottleneck in the creation and testing of geomathematical models in such disciplines as resource appraisal. ?? 1982.
Digital hardware implementation of a stochastic two-dimensional neuron model.
Grassia, F; Kohno, T; Levi, T
2016-11-01
This study explores the feasibility of stochastic neuron simulation in digital systems (FPGA), which realizes an implementation of a two-dimensional neuron model. The stochasticity is added by a source of current noise in the silicon neuron using an Ornstein-Uhlenbeck process. This approach uses digital computation to emulate individual neuron behavior using fixed point arithmetic operation. The neuron model's computations are performed in arithmetic pipelines. It was designed in VHDL language and simulated prior to mapping in the FPGA. The experimental results confirmed the validity of the developed stochastic FPGA implementation, which makes the implementation of the silicon neuron more biologically plausible for future hybrid experiments. Copyright © 2017 Elsevier Ltd. All rights reserved.
Choudhri, Asim F; Radvany, Martin G
2011-04-01
Medical imaging is commonly used to diagnose many emergent conditions, as well as plan treatment. Digital images can be reviewed on almost any computing platform. Modern mobile phones and handheld devices are portable computing platforms with robust software programming interfaces, powerful processors, and high-resolution displays. OsiriX mobile, a new Digital Imaging and Communications in Medicine viewing program, is available for the iPhone/iPod touch platform. This raises the possibility of mobile review of diagnostic medical images to expedite diagnosis and treatment planning using a commercial off the shelf solution, facilitating communication among radiologists and referring clinicians.
Engineering studies related to Skylab program. [assessment of automatic gain control data
NASA Technical Reports Server (NTRS)
Hayne, G. S.
1973-01-01
The relationship between the S-193 Automatic Gain Control data and the magnitude of received signal power was studied in order to characterize performance parameters for Skylab equipment. The r-factor was used for the assessment and is defined to be less than unity, and a function of off-nadir angle, ocean surface roughness, and receiver signal to noise ratio. A digital computer simulation was also used to assess to additive receiver, or white noise. The system model for the digital simulation is described, along with intermediate frequency and video impulse response functions used, details of the input waveforms, and results to date. Specific discussion of the digital computer programs used is also provided.
GEOMETRIC PROCESSING OF DIGITAL IMAGES OF THE PLANETS.
Edwards, Kathleen
1987-01-01
New procedures and software have been developed for geometric transformations of images to support digital cartography of the planets. The procedures involve the correction of spacecraft camera orientation of each image with the use of ground control and the transformation of each image to a Sinusoidal Equal-Area map projection with an algorithm which allows the number of transformation calculations to vary as the distortion varies within the image. When the distortion is low in an area of an image, few transformation computations are required, and most pixels can be interpolated. When distortion is extreme, the location of each pixel is computed. Mosaics are made of these images and stored as digital databases.
Application of digital control to a magnetic model suspension and balance model
NASA Technical Reports Server (NTRS)
Luh, P. B.; Covert, E. E.; Whitaker, H. P.; Haldeman, C. W.
1978-01-01
The feasibility of using a digital computer for performing the automatic control functions for a magnetic suspension and balance system (MSBS) for use with wind tunnel models was investigated. Modeling was done using both a prototype MSBS and a one dimensional magnetic balance. A microcomputer using the Intel 8080 microprocessor is described and results are given using this microprocessor to control the one dimensional balance. Hybrid simulations for one degree of freedom of the MSBS were also performed and are reported. It is concluded that use of a digital computer to control the MSBS is eminently feasible and should extend both the accuracy and utility of the system.
Digital pulse processing for planar TlBr detectors
NASA Astrophysics Data System (ADS)
Nakhostin, M.; Hitomi, K.; Ishii, K.; Kikuchi, Y.
2010-04-01
We report on a digital pulse processing algorithm for correction of charge trapping in the planar TlBr detectors. The algorithm is performed on the signals digitized at the preamplifier stage. The algorithm is very simple and is implemented with little computational effort. By using a digitizer with a sampling rate of 250 MSample/s and 8 bit resolution, an energy resolution of 6.5% is achieved at 511 keV with a 0.7 mm thick detector.
1991-06-01
intensive systems, including the use of onboard digital computers. Topics include: measurements that are digital in origin, sampling, encoding, transmitting...Individuals charged with designing aircraft measuring systems to become better acquainted with new solutions to their requirements. This volume Is...concerned with aircraft measuring systems as related to flight test and flight research. Measure - ments that are digital in origin or that must be
Integrating TV/digital data spectrograph system
NASA Technical Reports Server (NTRS)
Duncan, B. J.; Fay, T. D.; Miller, E. R.; Wamsteker, W.; Brown, R. M.; Neely, P. L.
1975-01-01
A 25-mm vidicon camera was previously modified to allow operation in an integration mode for low-light-level astronomical work. The camera was then mated to a low-dispersion spectrograph for obtaining spectral information in the 400 to 750 nm range. A high speed digital video image system was utilized to digitize the analog video signal, place the information directly into computer-type memory, and record data on digital magnetic tape for permanent storage and subsequent analysis.
Preliminary clinical evaluation of hard- and soft-copy digitized chest radiography
NASA Astrophysics Data System (ADS)
Rian, Roger L.; Smerud, Michael J.; Guinn, Todd
1994-05-01
The digital applications in radiology are a controversial advanced which potentially will influence all areas of patient imaging. It is utilized and accepted in angiography, computed tomography, magnetic resonance, nuclear imaging and sonography. More recently Computed Radiography has gained credibility in mobile scenarios as well as specific applications from cervical spine radiography to digital fluoroscopy. Usually this acceptance is related to benefits of lesser radiation exposure or an improved presentation with an incorrect radiographic technique. One advantage of interpreting from digital information is the potential manipulation of the image presentation to the observer through windowing, leveling and edge enhancement pre and/or during image review. Additionally this digital data can be transmitted over distance and represented as hard and/or soft copy for primary or consultative review. The number and quality of the images to be viewed, the environment of the review station as well as the observer experience with conventional radiographic as well as digital image evaluation are important aspects of delivering the radiologist's product i.e. the final interpretation. This paper assesses that product, specifically addressing the question `Is the radiologist's report the same whether derived from the original analog image or from its digitized image.' The object of this study is to determine whether a digital system (3M PACS) designed for consultative viewing in a satellite department can also be used directly for primary diagnosis of conventional chest exams.
NASA Astrophysics Data System (ADS)
Lhamon, Michael Earl
A pattern recognition system which uses complex correlation filter banks requires proportionally more computational effort than single-real valued filters. This introduces increased computation burden but also introduces a higher level of parallelism, that common computing platforms fail to identify. As a result, we consider algorithm mapping to both optical and digital processors. For digital implementation, we develop computationally efficient pattern recognition algorithms, referred to as, vector inner product operators that require less computational effort than traditional fast Fourier methods. These algorithms do not need correlation and they map readily onto parallel digital architectures, which imply new architectures for optical processors. These filters exploit circulant-symmetric matrix structures of the training set data representing a variety of distortions. By using the same mathematical basis as with the vector inner product operations, we are able to extend the capabilities of more traditional correlation filtering to what we refer to as "Super Images". These "Super Images" are used to morphologically transform a complicated input scene into a predetermined dot pattern. The orientation of the dot pattern is related to the rotational distortion of the object of interest. The optical implementation of "Super Images" yields feature reduction necessary for using other techniques, such as artificial neural networks. We propose a parallel digital signal processor architecture based on specific pattern recognition algorithms but general enough to be applicable to other similar problems. Such an architecture is classified as a data flow architecture. Instead of mapping an algorithm to an architecture, we propose mapping the DSP architecture to a class of pattern recognition algorithms. Today's optical processing systems have difficulties implementing full complex filter structures. Typically, optical systems (like the 4f correlators) are limited to phase-only implementation with lower detection performance than full complex electronic systems. Our study includes pseudo-random pixel encoding techniques for approximating full complex filtering. Optical filter bank implementation is possible and they have the advantage of time averaging the entire filter bank at real time rates. Time-averaged optical filtering is computational comparable to billions of digital operations-per-second. For this reason, we believe future trends in high speed pattern recognition will involve hybrid architectures of both optical and DSP elements.
Computational approach to integrate 3D X-ray microtomography and NMR data
NASA Astrophysics Data System (ADS)
Lucas-Oliveira, Everton; Araujo-Ferreira, Arthur G.; Trevizan, Willian A.; Fortulan, Carlos A.; Bonagamba, Tito J.
2018-07-01
Nowadays, most of the efforts in NMR applied to porous media are dedicated to studying the molecular fluid dynamics within and among the pores. These analyses have a higher complexity due to morphology and chemical composition of rocks, besides dynamic effects as restricted diffusion, diffusional coupling, and exchange processes. Since the translational nuclear spin diffusion in a confined geometry (e.g. pores and fractures) requires specific boundary conditions, the theoretical solutions are restricted to some special problems and, in many cases, computational methods are required. The Random Walk Method is a classic way to simulate self-diffusion along a Digital Porous Medium. Bergman model considers the magnetic relaxation process of the fluid molecules by including a probability rate of magnetization survival under surface interactions. Here we propose a statistical approach to correlate surface magnetic relaxivity with the computational method applied to the NMR relaxation in order to elucidate the relationship between simulated relaxation time and pore size of the Digital Porous Medium. The proposed computational method simulates one- and two-dimensional NMR techniques reproducing, for example, longitudinal and transverse relaxation times (T1 and T2, respectively), diffusion coefficients (D), as well as their correlations. For a good approximation between the numerical and experimental results, it is necessary to preserve the complexity of translational diffusion through the microstructures in the digital rocks. Therefore, we use Digital Porous Media obtained by 3D X-ray microtomography. To validate the method, relaxation times of ideal spherical pores were obtained and compared with the previous determinations by the Brownstein-Tarr model, as well as the computational approach proposed by Bergman. Furthermore, simulated and experimental results of synthetic porous media are compared. These results make evident the potential of computational physics in the analysis of the NMR data for complex porous materials.
On the impact of approximate computation in an analog DeSTIN architecture.
Young, Steven; Lu, Junjie; Holleman, Jeremy; Arel, Itamar
2014-05-01
Deep machine learning (DML) holds the potential to revolutionize machine learning by automating rich feature extraction, which has become the primary bottleneck of human engineering in pattern recognition systems. However, the heavy computational burden renders DML systems implemented on conventional digital processors impractical for large-scale problems. The highly parallel computations required to implement large-scale deep learning systems are well suited to custom hardware. Analog computation has demonstrated power efficiency advantages of multiple orders of magnitude relative to digital systems while performing nonideal computations. In this paper, we investigate typical error sources introduced by analog computational elements and their impact on system-level performance in DeSTIN--a compositional deep learning architecture. These inaccuracies are evaluated on a pattern classification benchmark, clearly demonstrating the robustness of the underlying algorithm to the errors introduced by analog computational elements. A clear understanding of the impacts of nonideal computations is necessary to fully exploit the efficiency of analog circuits.
NASA Astrophysics Data System (ADS)
Marinos, Alexandros; Briscoe, Gerard
Cloud Computing is rising fast, with its data centres growing at an unprecedented rate. However, this has come with concerns over privacy, efficiency at the expense of resilience, and environmental sustainability, because of the dependence on Cloud vendors such as Google, Amazon and Microsoft. Our response is an alternative model for the Cloud conceptualisation, providing a paradigm for Clouds in the community, utilising networked personal computers for liberation from the centralised vendor model. Community Cloud Computing (C3) offers an alternative architecture, created by combing the Cloud with paradigms from Grid Computing, principles from Digital Ecosystems, and sustainability from Green Computing, while remaining true to the original vision of the Internet. It is more technically challenging than Cloud Computing, having to deal with distributed computing issues, including heterogeneous nodes, varying quality of service, and additional security constraints. However, these are not insurmountable challenges, and with the need to retain control over our digital lives and the potential environmental consequences, it is a challenge we must pursue.
Institutionalizing human-computer interaction for global health
Gulliksen, Jan
2017-01-01
ABSTRACT Digitalization is the societal change process in which new ICT-based solutions bring forward completely new ways of doing things, new businesses and new movements in the society. Digitalization also provides completely new ways of addressing issues related to global health. This paper provides an overview of the field of human-computer interaction (HCI) and in what way the field has contributed to international development in different regions of the world. Additionally, it outlines the United Nations’ new sustainability goals from December 2015 and what these could contribute to the development of global health and its relationship to digitalization. Finally, it argues why and how HCI could be adopted and adapted to fit the contextual needs, the need for localization and for the development of new digital innovations. The research methodology is mostly qualitative following an action research paradigm in which the actual change process that the digitalization is evoking is equally important as the scientific conclusions that can be drawn. In conclusion, the paper argues that digitalization is fundamentally changing the society through the development and use of digital technologies and may have a profound effect on the digital development of every country in the world. But it needs to be developed based on local practices, it needs international support and to not be limited by any technological constraints. Particularly digitalization to support global health requires a profound understanding of the users and their context, arguing for user-centred systems design methodologies as particularly suitable. PMID:28838309
Digital interactive learning of oral radiographic anatomy.
Vuchkova, J; Maybury, T; Farah, C S
2012-02-01
Studies reporting high number of diagnostic errors made from radiographs suggest the need to improve the learning of radiographic interpretation in the dental curriculum. Given studies that show student preference for computer-assisted or digital technologies, the purpose of this study was to develop an interactive digital tool and to determine whether it was more successful than a conventional radiology textbook in assisting dental students with the learning of radiographic anatomy. Eighty-eight dental students underwent a learning phase of radiographic anatomy using an interactive digital tool alongside a conventional radiology textbook. The success of the digital tool, when compared to the textbook, was assessed by quantitative means using a radiographic interpretation test and by qualitative means using a structured Likert scale survey, asking students to evaluate their own learning outcomes from the digital tool. Student evaluations of the digital tool showed that almost all participants (95%) indicated that the tool positively enhanced their learning of radiographic anatomy and interpretation. The success of the digital tool in assisting the learning of radiographic interpretation is discussed in the broader context of learning and teaching curricula, and preference (by students) for the use of this digital form when compared to the conventional literate form of the textbook. Whilst traditional textbooks are still valued in the dental curriculum, it is evident that the preference for computer-assisted learning of oral radiographic anatomy enhances the learning experience by enabling students to interact and better engage with the course material. © 2011 John Wiley & Sons A/S.
ERIC Educational Resources Information Center
Travis, John
1991-01-01
A discipline in which scientists seek to simulate and synthesize lifelike behaviors within computers, chemical mixtures, and other media is discussed. A computer program with self-replicating digital "organisms" that evolve as they compete for computer time and memory is described. (KR)
Thermal radiation view factor: Methods, accuracy and computer-aided procedures
NASA Technical Reports Server (NTRS)
Kadaba, P. V.
1982-01-01
The computer aided thermal analysis programs which predicts the result of predetermined acceptable temperature range prior to stationing of these orbiting equipment in various attitudes with respect to the Sun and the Earth was examined. Complexity of the surface geometries suggests the use of numerical schemes for the determination of these viewfactors. Basic definitions and standard methods which form the basis for various digital computer methods and various numerical methods are presented. The physical model and the mathematical methods on which a number of available programs are built are summarized. The strength and the weaknesses of the methods employed, the accuracy of the calculations and the time required for computations are evaluated. The situations where accuracies are important for energy calculations are identified and methods to save computational times are proposed. Guide to best use of the available programs at several centers and the future choices for efficient use of digital computers are included in the recommendations.
A generalized approach to computer synthesis of digital holograms
NASA Technical Reports Server (NTRS)
Hopper, W. A.
1973-01-01
Hologram is constructed by taking number of digitized sample points and blending them together to form ''continuous'' picture. New system selects better set of sample points resulting in improved hologram from same amount of information.
Developing an undergraduate geography course on digital image processing of remotely sensed data
NASA Technical Reports Server (NTRS)
Baumann, P. R.
1981-01-01
Problems relating to the development of a digital image processing course in an undergraduate geography environment is discussed. Computer resource requirements, course prerequisites, and the size of the study area are addressed.
Telehealth for "the digital illiterate"--elderly heart failure patients experiences.
Lind, Leili; Karlsson, Daniel
2014-01-01
Telehealth solutions should be available also for elderly patients with no interest in using, or capacity to use, computers and smartphones. Fourteen elderly, severely ill heart failure patients in home care participated in a telehealth study and used digital pens for daily reporting of their health state--a technology never used before by this patient group. After the study seven patients and two spouses were interviewed face-to-face. A qualitative content analysis of the interview material was performed. The informants had no experience of computers or the Internet and no interest in learning. Still, patients found the digital pen and the health diary form easy to use, thus effortlessly adopting to changes in care provision. They experienced an improved contact with the caregivers and had a sense of increased security despite a multimorbid state. Our study shows that, given that technologies are tailored to specific patient groups, even "the digital illiterate" may use the Internet.
Digitizing Sound: How Can Sound Waves be Turned into Ones and Zeros?
NASA Astrophysics Data System (ADS)
Vick, Matthew
2010-10-01
From MP3 players to cell phones to computer games, we're surrounded by a constant stream of ones and zeros. Do we really need to know how this technology works? While nobody can understand everything, digital technology is increasingly making our lives a collection of "black boxes" that we can use but have no idea how they work. Pursuing scientific literacy should propel us to open up a few of these metaphorical boxes. High school physics offers opportunities to connect the curriculum to sports, art, music, and electricity, but it also offers connections to computers and digital music. Learning activities about digitizing sounds offer wonderful opportunities for technology integration and student problem solving. I used this series of lessons in high school physics after teaching about waves and sound but before optics and total internal reflection so that the concepts could be further extended when learning about fiber optics.
1983-09-01
duplicate a continuous function on a digital computer, and thus the machine representatic- of the GMA is only a close approximation of the continuous...error process. Thus, the manner in which the GMA process is digitally replicated has an effect on the results of the simulation. The parameterization of...Information Center 2 Cameron Station Alexandria, Virginia 22314 2. Libary , Code 0142 2 Naval Postgraduate School Monterey, California 93943 3. Professor
ERIC Educational Resources Information Center
Congress of the U.S., Washington, DC. House Committee on Science, Space and Technology.
The integration of television into a digital framework makes possible the merger of television and computers. Development of a digital system will permit the consumer to receive television and computer images on the same screen at a quality approaching 35mm film. If fiber optic telecommunications lines are linked to the home and standards are…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fuller, L.C.
The ORCENT-II digital computer program will perform calculations at valves-wide-open design conditions, maximum guaranteed rating conditions, and an approximation of part-load conditions for steam turbine cycles supplied with throttle steam characteristic of contemporary light-water reactors. Turbine performance calculations are based on a method published by the General Electric Company. Output includes all information normally shown on a turbine-cycle heat balance diagram. The program is written in FORTRAN IV for the IBM System 360 digital computers at the Oak Ridge National Laboratory.
Digital Waveguide Architectures for Virtual Musical Instruments
NASA Astrophysics Data System (ADS)
Smith, Julius O.
Digital sound synthesis has become a standard staple of modern music studios, videogames, personal computers, and hand-held devices. As processing power has increased over the years, sound synthesis implementations have evolved from dedicated chip sets, to single-chip solutions, and ultimately to software implementations within processors used primarily for other tasks (such as for graphics or general purpose computing). With the cost of implementation dropping closer and closer to zero, there is increasing room for higher quality algorithms.
Durfee, Sara M; Jain, Sidney; Shaffer, Kitt
2003-02-01
The purpose of this study was to define the current use of information technology in radiology tutorials for medical students. The authors conducted a Web-based survey of directors of medical school courses in radiology. The survey dealt with the details of the courses and the use of computers and the Web during the courses. There were 48 responses. Most radiology courses were elective (73%) and were offered monthly. Most institutions (79%) had picture archiving and communication systems (PACS) available or were completely filmless. The teaching case presentations, however, often included film images displayed on a view box or by an overhead projector. Computers dedicated to student use were uncommon (28%). The Web was used infrequently as a teaching resource, and a Web site was not available in most courses. Computer technical support was variable and usually provided by the course director. Course directors at institutions with PACS were more likely to use digital technology for case presentations and more likely to use the Web for teaching purposes. Despite the widespread use of digital technology and PACS in the field of radiology, digital technology is underused in radiology courses. However, departments with PACS tend to use digital technology more frequently in education than do departments without PACS.
Yu, Quan; Gong, Xin; Wang, Guo-Min; Yu, Zhe-Yuan; Qian, Yu-Fen; Shen, Gang
2011-01-01
To establish a new method of presurgical nasoalveolar molding (NAM) using computer-aided reverse engineering and rapid prototyping technique in infants with unilateral cleft lip and palate (UCLP). Five infants (2 males and 3 females with mean age of 1.2 w) with complete UCLP were recruited. All patients were subjected to NAM before the cleft lip repair. The upper denture casts were recorded using a three-dimensional laser scanner within 2 weeks after birth in UCLP infants. A digital model was constructed and analyzed to simulate the NAM procedure with reverse engineering software. The digital geometrical data were exported to print the solid model with rapid prototyping system. The whole set of appliances was fabricated based on these solid models. Laser scanning and digital model construction simplified the NAM procedure and estimated the treatment objective. The appliances were fabricated based on the rapid prototyping technique, and for each patient, the complete set of appliances could be obtained at one time. By the end of presurgical NAM treatment, the cleft was narrowed, and the malformation of nasoalveolar segments was aligned normally. We have developed a novel technique of presurgical NAM based on a computer-aided design. The accurate digital denture model of UCLP infants could be obtained with laser scanning. The treatment design and appliance fabrication could be simplified with a computer-aided reverse engineering and rapid prototyping technique.
Training system for digital mammographic diagnoses of breast cancer
NASA Astrophysics Data System (ADS)
Thomaz, R. L.; Nirschl Crozara, M. G.; Patrocinio, A. C.
2013-03-01
As the technology evolves, the analog mammography systems are being replaced by digital systems. The digital system uses video monitors as the display of mammographic images instead of the previously used screen-film and negatoscope for analog images. The change in the way of visualizing mammographic images may require a different approach for training the health care professionals in diagnosing the breast cancer with digital mammography. Thus, this paper presents a computational approach to train the health care professionals providing a smooth transition between analog and digital technology also training to use the advantages of digital image processing tools to diagnose the breast cancer. This computational approach consists of a software where is possible to open, process and diagnose a full mammogram case from a database, which has the digital images of each of the mammographic views. The software communicates with a gold standard digital mammogram cases database. This database contains the digital images in Tagged Image File Format (TIFF) and the respective diagnoses according to BI-RADSTM, these files are read by software and shown to the user as needed. There are also some digital image processing tools that can be used to provide better visualization of each single image. The software was built based on a minimalist and a user-friendly interface concept that might help in the smooth transition. It also has an interface for inputting diagnoses from the professional being trained, providing a result feedback. This system has been already completed, but hasn't been applied to any professional training yet.
Airborne Advanced Reconfigurable Computer System (ARCS)
NASA Technical Reports Server (NTRS)
Bjurman, B. E.; Jenkins, G. M.; Masreliez, C. J.; Mcclellan, K. L.; Templeman, J. E.
1976-01-01
A digital computer subsystem fault-tolerant concept was defined, and the potential benefits and costs of such a subsystem were assessed when used as the central element of a new transport's flight control system. The derived advanced reconfigurable computer system (ARCS) is a triple-redundant computer subsystem that automatically reconfigures, under multiple fault conditions, from triplex to duplex to simplex operation, with redundancy recovery if the fault condition is transient. The study included criteria development covering factors at the aircraft's operation level that would influence the design of a fault-tolerant system for commercial airline use. A new reliability analysis tool was developed for evaluating redundant, fault-tolerant system availability and survivability; and a stringent digital system software design methodology was used to achieve design/implementation visibility.
NASA Technical Reports Server (NTRS)
Bennett, R. L.
1975-01-01
The analytical techniques and computer program developed in the fully-coupled rotor vibration study are described. The rotor blade natural frequency and mode shape analysis was implemented in a digital computer program designated DF1758. The program computes collective, cyclic, and scissor modes for a single blade within a specified range of frequency for specified values of rotor RPM and collective angle. The analysis includes effects of blade twist, cg offset from reference axis, and shear center offset from reference axis. Coupled inplane, out-of-plane, and torsional vibrations are considered. Normalized displacements, shear forces and moments may be printed out and Calcomp plots of natural frequencies as a function of rotor RPM may be produced.
The engineering design integration (EDIN) system. [digital computer program complex
NASA Technical Reports Server (NTRS)
Glatt, C. R.; Hirsch, G. N.; Alford, G. E.; Colquitt, W. N.; Reiners, S. J.
1974-01-01
A digital computer program complex for the evaluation of aerospace vehicle preliminary designs is described. The system consists of a Univac 1100 series computer and peripherals using the Exec 8 operating system, a set of demand access terminals of the alphanumeric and graphics types, and a library of independent computer programs. Modification of the partial run streams, data base maintenance and construction, and control of program sequencing are provided by a data manipulation program called the DLG processor. The executive control of library program execution is performed by the Univac Exec 8 operating system through a user established run stream. A combination of demand and batch operations is employed in the evaluation of preliminary designs. Applications accomplished with the EDIN system are described.
The Use of Digital Technologies across the Adult Life Span in Distance Education
ERIC Educational Resources Information Center
Jelfs, Anne; Richardson, John T. E.
2013-01-01
In June 2010, a survey was carried out to explore access to digital technology, attitudes to digital technology and approaches to studying across the adult life span in students taking courses with the UK Open University. In total, 7000 people were surveyed, of whom more than 4000 responded. Nearly all these students had access to a computer and…
Lost Identity: The Assimilation of Digital Libraries into the Web
ERIC Educational Resources Information Center
Lagoze, Carl Jay
2010-01-01
The idea of Digital Libraries emerged in the early 1990s from a vision of a "library of the future", without walls and open 24 hours a day. These digital libraries would leverage the substantial investments of federal funding in the Internet and advanced computing for the benefit of the entire population. The world's knowledge would be a key press…
ERIC Educational Resources Information Center
Çelik, Servet; Aytin, Kübra
2014-01-01
Despite the clear benefits provided by digital educational tools, Turkish teachers of English as a foreign language (EFL) are often seen as failing to take advantage of computing technologies in the classroom. Deficiencies in terms of teachers' digital literacies are often faulted for this omission. The majority of studies concerning Turkish EFL…
ERIC Educational Resources Information Center
McAdams, Laurie
2013-01-01
The digital age has impacted education and how teachers prepare students to master 21st century literacies. Numerous national, state, and local entities have made the integration of technology into the literacy curriculum a priority, and teachers are becoming more proficient with their use of digital tools. However, integrating technology to…
ERIC Educational Resources Information Center
Hoge, Robert Joaquin
2010-01-01
Within the sphere of education, navigating throughout a digital world has become a matter of necessity for the developing professional, as with the advent of Document Camera Technology (DCT). This study explores the pedagogical implications of implementing DCT; to see if there is a relationship between teachers' comfort with DCT and to the…
The Digital Natives Are Restless: Inspiring a New Generation of Learners
ERIC Educational Resources Information Center
Rudi, Alan
2012-01-01
The current crop of "digital natives"--kids born into a world of modern technology--has been immersed in a world of video games, computers, digital music players, and cell phones from an early age. Shaped by the Internet, Google searches, and instant messaging, they can't imagine life without technology. Theirs is a vastly different world from…
ERIC Educational Resources Information Center
Newhouse, C. Paul
2015-01-01
This paper reports on the outcomes of a three-year study investigating the use of digital technologies to increase the authenticity of high-stakes summative assessment in four Western Australian senior secondary courses. The study involved 82 teachers and 1015 students and a range of digital forms of assessment using computer-based exams, digital…
ERIC Educational Resources Information Center
Folkestad, James E.; Banning, James
2010-01-01
Digital media applications (DMAs) have emerged in abundance over the last ten years. Enabled by exponential growth in computing power and inexpensive data storage, these applications are easy to use and inexpensive (often free) to own. DMAs not only allow users to produce digital content efficiently they allow users to exploit the connective power…
Instant Grainification: Real-Time Grain-Size Analysis from Digital Images in the Field
NASA Astrophysics Data System (ADS)
Rubin, D. M.; Chezar, H.
2007-12-01
Over the past few years, digital cameras and underwater microscopes have been developed to collect in-situ images of sand-sized bed sediment, and software has been developed to measure grain size from those digital images (Chezar and Rubin, 2004; Rubin, 2004; Rubin et al., 2006). Until now, all image processing and grain- size analysis was done back in the office where images were uploaded from cameras and processed on desktop computers. Computer hardware has become small and rugged enough to process images in the field, which for the first time allows real-time grain-size analysis of sand-sized bed sediment. We present such a system consisting of weatherproof tablet computer, open source image-processing software (autocorrelation code of Rubin, 2004, running under Octave and Cygwin), and digital camera with macro lens. Chezar, H., and Rubin, D., 2004, Underwater microscope system: U.S. Patent and Trademark Office, patent number 6,680,795, January 20, 2004. Rubin, D.M., 2004, A simple autocorrelation algorithm for determining grain size from digital images of sediment: Journal of Sedimentary Research, v. 74, p. 160-165. Rubin, D.M., Chezar, H., Harney, J.N., Topping, D.J., Melis, T.S., and Sherwood, C.R., 2006, Underwater microscope for measuring spatial and temporal changes in bed-sediment grain size: USGS Open-File Report 2006-1360.
X-Ray Computed Tomography Monitors Damage in Composites
NASA Technical Reports Server (NTRS)
Baaklini, George Y.
1997-01-01
The NASA Lewis Research Center recently codeveloped a state-of-the-art x-ray CT facility (designated SMS SMARTSCAN model 100-112 CITA by Scientific Measurement Systems, Inc., Austin, Texas). This multipurpose, modularized, digital x-ray facility includes an imaging system for digital radiography, CT, and computed laminography. The system consists of a 160-kV microfocus x-ray source, a solid-state charge-coupled device (CCD) area detector, a five-axis object-positioning subassembly, and a Sun SPARCstation-based computer system that controls data acquisition and image processing. The x-ray source provides a beam spot size down to 3 microns. The area detector system consists of a 50- by 50- by 3-mm-thick terbium-doped glass fiber-optic scintillation screen, a right-angle mirror, and a scientific-grade, digital CCD camera with a resolution of 1000 by 1018 pixels and 10-bit digitization at ambient cooling. The digital output is recorded with a high-speed, 16-bit frame grabber that allows data to be binned. The detector can be configured to provide a small field-of-view, approximately 45 by 45 mm in cross section, or a larger field-of-view, approximately 60 by 60 mm in cross section. Whenever the highest spatial resolution is desired, the small field-of-view is used, and for larger samples with some reduction in spatial resolution, the larger field-of-view is used.
Integration of Digital Dental Casts in Cone-Beam Computed Tomography Scans
Rangel, Frits A.; Maal, Thomas J. J.; Bergé, Stefaan J.; Kuijpers-Jagtman, Anne Marie
2012-01-01
Cone-beam computed tomography (CBCT) is widely used in maxillofacial surgery. The CBCT image of the dental arches, however, is of insufficient quality to use in digital planning of orthognathic surgery. Several authors have described methods to integrate digital dental casts into CBCT scans, but all reported methods have drawbacks. The aim of this feasibility study is to present a new simplified method to integrate digital dental casts into CBCT scans. In a patient scheduled for orthognathic surgery, titanium markers were glued to the gingiva. Next, a CBCT scan and dental impressions were made. During the impression-taking procedure, the titanium markers were transferred to the impression. The impressions were scanned, and all CBCT datasets were exported in DICOM format. The two datasets were matched, and the dentition derived from the scanned impressions was transferred to the CBCT of the patient. After matching the two datasets, the average distance between the corresponding markers was 0.1 mm. This novel method allows for the integration of digital dental casts into CBCT scans, overcoming problems such as unwanted extra radiation exposure, distortion of soft tissues due to the use of bite jigs, and time-consuming digital data handling. PMID:23050159
Do pre-trained deep learning models improve computer-aided classification of digital mammograms?
NASA Astrophysics Data System (ADS)
Aboutalib, Sarah S.; Mohamed, Aly A.; Zuley, Margarita L.; Berg, Wendie A.; Luo, Yahong; Wu, Shandong
2018-02-01
Digital mammography screening is an important exam for the early detection of breast cancer and reduction in mortality. False positives leading to high recall rates, however, results in unnecessary negative consequences to patients and health care systems. In order to better aid radiologists, computer-aided tools can be utilized to improve distinction between image classifications and thus potentially reduce false recalls. The emergence of deep learning has shown promising results in the area of biomedical imaging data analysis. This study aimed to investigate deep learning and transfer learning methods that can improve digital mammography classification performance. In particular, we evaluated the effect of pre-training deep learning models with other imaging datasets in order to boost classification performance on a digital mammography dataset. Two types of datasets were used for pre-training: (1) a digitized film mammography dataset, and (2) a very large non-medical imaging dataset. By using either of these datasets to pre-train the network initially, and then fine-tuning with the digital mammography dataset, we found an increase in overall classification performance in comparison to a model without pre-training, with the very large non-medical dataset performing the best in improving the classification accuracy.
Computer Languages: A Practical Guide to the Chief Programming Languages.
ERIC Educational Resources Information Center
Sanderson, Peter C.
All the most commonly-used high-level computer languages are discussed in this book. An introductory discussion provides an overview of the basic components of a digital computer, the general planning of a computer programing problem, and the various types of computer languages. Each chapter is self-contained, emphasizes those features of a…
Computer-aided Instructional System for Transmission Line Simulation.
ERIC Educational Resources Information Center
Reinhard, Erwin A.; Roth, Charles H., Jr.
A computer-aided instructional system has been developed which utilizes dynamic computer-controlled graphic displays and which requires student interaction with a computer simulation in an instructional mode. A numerical scheme has been developed for digital simulation of a uniform, distortionless transmission line with resistive terminations and…
Formulation of a strategy for monitoring control integrity in critical digital control systems
NASA Technical Reports Server (NTRS)
Belcastro, Celeste M.; Fischl, Robert; Kam, Moshe
1991-01-01
Advanced aircraft will require flight critical computer systems for stability augmentation as well as guidance and control that must perform reliably in adverse, as well as nominal, operating environments. Digital system upset is a functional error mode that can occur in electromagnetically harsh environments, involves no component damage, can occur simultaneously in all channels of a redundant control computer, and is software dependent. A strategy is presented for dynamic upset detection to be used in the evaluation of critical digital controllers during the design and/or validation phases of development. Critical controllers must be able to be used in adverse environments that result from disturbances caused by an electromagnetic source such as lightning, high intensity radiated field (HIRF), and nuclear electromagnetic pulses (NEMP). The upset detection strategy presented provides dynamic monitoring of a given control computer for degraded functional integrity that can result from redundancy management errors and control command calculation error that could occur in an electromagnetically harsh operating environment. The use is discussed of Kalman filtering, data fusion, and decision theory in monitoring a given digital controller for control calculation errors, redundancy management errors, and control effectiveness.
Koivusilta, Leena K; Lintonen, Tomi P; Rimpelä, Arja H
2007-01-01
The role of information and communication technology (ICT) in adolescents' lives was studied, with emphasis on whether there exists a digital divide based on sociodemographic background, educational career, and health. The assumption was that some groups of adolescents use ICT more so that their information utilization skills improve (computer use), while others use it primarily for entertainment (digital gaming, contacting friends by mobile phone). Data were collected by mailed survey from a nationally representative sample of 12- to 18-year-olds (n=7,292; response 70%) in 2001 and analysed using ANOVA. Computer use was most frequent among adolescents whose fathers had higher education or socioeconomic status, who came from nuclear families, and who continued studies after compulsory education. Digital gaming was associated with poor school achievement and attending vocational rather than upper secondary school. Mobile phone use was frequent among adolescents whose fathers had lower education or socioeconomic status, who came from non-nuclear families, and whose educational prospects were poor. Intensive use of each ICT form, especially of mobile phones, was associated with health problems. High social position, nuclear family, and a successful educational career signified good health in general, independently of the diverse usage of ICT. There exists a digital divide among adolescents: orientation to computer use is more common in educated well-off families while digital gaming and mobile phone use accumulate at the opposite end of the spectrum. Poorest health was reported by mobile phone users. High social background and success at school signify better health, independently of the ways of using ICT.
Computer generated maps from digital satellite data - A case study in Florida
NASA Technical Reports Server (NTRS)
Arvanitis, L. G.; Reich, R. M.; Newburne, R.
1981-01-01
Ground cover maps are important tools to a wide array of users. Over the past three decades, much progress has been made in supplementing planimetric and topographic maps with ground cover details obtained from aerial photographs. The present investigation evaluates the feasibility of using computer maps of ground cover from satellite input tapes. Attention is given to the selection of test sites, a satellite data processing system, a multispectral image analyzer, general purpose computer-generated maps, the preliminary evaluation of computer maps, a test for areal correspondence, the preparation of overlays and acreage estimation of land cover types on the Landsat computer maps. There is every indication to suggest that digital multispectral image processing systems based on Landsat input data will play an increasingly important role in pattern recognition and mapping land cover in the years to come.
Pazhur, R J; Kutter, B; Georgieff, M; Schraag, S
2003-06-01
Portable digital assistants (PDAs) may be of value to the anaesthesiologist as development in medical care is moving towards "bedside computing". Many different portable computers are currently available and it is now possible for the physician to carry a mobile computer with him all the time. It is data base, reference book, patient tracking help, date planner, computer, book, magazine, calculator and much more in one mobile device. With the help of a PDA, information that is required for our work may be available at all times and everywhere at the point of care within seconds. In this overview the possibilities for the use of PDAs in anaesthesia and intensive care medicine are discussed. Developments in other countries, possibilities in use but also problems such as data security and network technology are evaluated.