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CreatorTitleDescriptionSubjectDate
76 Stringfellow, Gerald B.Mechanism for liquid phase epitaxial growth of nonequilibrium compositions producing a coherent interfaceA model is presented for growth by so-called composition pulling, wherein an epitaxial deposit grows coherently but with a composition different from that which would be in bulk equilibrium with the liquid phase from which growth occurs. The breakdown of coherent growth occurs when a dislocation nuc...Lattice-matching overgrowths; Composition pulling; Dislocation interface1977
77 Faugeras, Olivier DominiqueDigital color image processing and psychophysics within the framework of a human visual modelA three-dimensional homomorphic model of human color vision based on neurophysiological and psychophysical evidence is presented. This model permits the quantitative definition of perceptually important parameters such as brightness. saturation, huo and strength. By modelling neural interaction in t...Human visual model; Neurophysiological evidence; Psychophysical evidence1977
78 Pershing, David W.; Wendt, Jost O. L.Pulverized coal combustion: the influence of flame temperature and coal composition on thermal and fuel NOxA laboratory combustor was used to investigate the factors that influence the conversion of fuel nitrogen in coal during coal combustion. Fuel NO was isolated by experimentation utilizing Argon / Oxygen / Carbon Dioxide mixtures as the oxidant, and care was taken to compare cases with air at matche...Fuel nitrogen; Flame temperature; Coal composition1977
79 Allen, Edgar S.Sensory information processing (1 July 1975 - 31 December 1975)In the previous semi-annual report a new method was described for removing blur from photographic images. Several experiments are described here illustrating the effect of adjusting the cutoff frequency of filters used in the restoration scheme.Blur; Photographic images; Restoration scheme1977
80 Boll, Steven F.; Done, William JohnNoise suppression methods for robust speech processing (1 Oct. 1978- 31 Mar. 1981)Robust speech processing in practical operating environments requires effective environmental and processor noise suppression. This report describes the technical findings and accomplishments during this reporting period for period for research program funded to develop real time, compressed speech ...Noise suppression; Compressed speech analysis-synthesis algorithms; Signal contamination1978
81 Davis, Alan L.Data driven nets: a maximally concurrent, procedural, parallel process representation for distributed control systemsA procedural parallel process representation, known as data-driven nets is described. The sequencing mechanism of the data-driven representation is based on the principle of data dependency. Operations are driven into action by the arrival of the required working set of input operands. Execution of ...Data driven nets1978
82 Keller, Robert M.Sentinels: A concept for multiprocess coordinationThe sentinel construct is introduced, which provides a certain syntactic and semantic framework for multiprocess coordination. The advantage of this construct over others is argued to be semantic transparency, efficiency, ease in implementation, and usefulness in verfication.Sentinels; Multiprocess coordination; Sentinel construct1978
83 Keller, Robert M.; Lindstrom, Gary E.An architecture for a loosely-coupled parallel processorAn architecture for a large (e. g. 1000 processor) parallel computer is presented. The processors are loosely-coupled, in the sense that communication among them is fully asynchronous, and each processor is generally not unduly delayed by any immediate need for specific data values. The network supp...Loosely-coupled; Parallel processors1978
84 Evans, DavidDisplay of complex three dimensional finite element modelsComplex three dimensional models can be displayed after an automatic generation of a finite element (panel) mapping. although this automatic generation algorithm fails at certain levels of model complexity, the elimination of these failures can be accomplished through user interaction. This report p...Three dimensional models; Finite element models1978
85 Keller, Robert M.An approach to determinacy proofsIt is known that any parallel program graph composed of continuous operators itself represents a continuous function. In other words, the network is determinate in the sense that for a given input, the output is unique, independent of the timing of the constituent operators. This result is applied t...Parallel program graph; Determinacy proofs1978
86 Boll, Steven F.Suppression of acoustic noise in speech using two microphone adaptive noise cancellationAcoustic noise with energy greater or equal to the speech is suppressed by filtering a separately recorded correlated noise signal and subtracting it from the speech waveform. This approach was investigated to determine the degree of noise suppression possible using an external correlated input. The...Suppression; acoustic noise; adaptive noise cancellation1979
87 Boll, Steven F.; Timothy, LaMar K.Noise suppression methods for robust speech processing (1 Oct. 1978- 31 Mar. 1979)Robust speech processing in practical operating environments requires effective environmental and processor noise suppression. This report describes the technical findings and accomplishments during this reporting period for the research program funded to develop real time, compressed speech analysi...Noise suppression; Signal contamination; Compressed speech analysis-synthesis algorithms1979
88 Lindstrom, Gary E.Alpha-beta pruning on evolving game treesThe alpha-beta strategy is a widely used method for economizing on the size of game trees. Heretofore, its application has been limited to depth-first tree growth in recursive search functions. However, many modern game players use retentive (i.e. coroutine-based) control to achieve greater attentio...Alpha-beta pruning; Game trees1979
89 Organick, Elliott I.CASL - A language for automating the implementation of computer architecturesThe computer Architecture Specification Language (CASL), described in this paper, is intended for use by computer architects CASL is a state machine description language especially useful for describing digital systems at the "register transfer" level and designed to meet the needs of the computer a...Computer Architecture Specification Language1979
90 Pershing, David W.; Wendt, Jost O. L.Pulverized coal combustion: NOx formation mechanisms under fuel rich and staged combustion conditionsA 2 Kg/h pulverized fuel one dimensional flame combustor was used to determine time resolved NO profiles under fuel rich and staged combustion conditions. Seven solid fuels, including two coal chars, were investigated. Results show that at all fuel rich conditions NO is formed rapidly and then is ...Flame; Composition; Reaction1979
91 Riesenfeld, Richard F.Discrete B-splines and subdivision techniques in compter-aided geometric design and computer graphicsThe relevant theory of discrete 5-sphnes with associated new algorithms is extended to provide a framework for understanding and implementing general subdivision schemes for nonuniform B-splines. The new derived polygon corresponding to an arbitrary refinement of the knot vector for an existing .B-...1979
92 Pulsipher, Dennis CarlApplication of adaptive noise cancellation to noise reduction in audio signalsThe LMS adaptive noise cancellation algorithm has been applied to the removal of high-level white noise from audio signals. Simulations and actual acoustically recorded signals have been processed successfully, with excellent agreement between the results obtained from simulations and the results ob...Noise cancellation; Noise reduction; White noise; LMS algorithm1979
93 Riesenfeld, Richard F.The application of total positivity to computer aided curve and surface designOf particular importance in an interactive curve and surface design system is the interface to the user. The mathematical model employed in the system must be sufficiently flexible for interaction between designer and machine to converge to a satisfactory result. The mathematical theory of Total Pos...interactive curves; total positivity1979
94 Done, William JohnEstimation of the parameters of an autoregressive process in the presence of additive white noiseApplications of linear prediction (LP) algorithms have been successful in modeling various physical processes. In the area of speech analysis this has resulted in the development of LP vocoders, devices used in digital speech communication systems. The LP algorithms used in speech and other areas ar...Autoregressive process; Linear prediction algorithms; All-pole model1979
95 Pershing, David W.Influence of fuel composition and flame temperature on the formation of thermal and fuel NOx in residual oil flamesA 900 kw model package boiler and a 20 kw laboratory tunnel furnace were used to study fuel and thermal NO, formation during heavy oil combustion. Package boiler results indicated that atomizer design, spray/ flow field interactions, and fuel composition were significant, dependent parameters. These...Residual oil flames1979
96 Boll, Steven F.Noise suppression methods for robust speech processing (1 April 1979- 30 Sept. 1979)Robust speech processing in practical operating environments requires effective environmental and processor noise suppression. This report describes the technical findings and accomplishments during this reporting period for the research program funded to develop real-time, compressed speech analysi...Noise suppression; Signal contamination; Compressed speech analysis-synthesis algorithms1979
97 Lindstrom, Gary E.Referencing and retention in block-structured coroutinesThe combination of coroutines with recursive procedures is characteristic of many modern higher-level languages offering advanced control structures (e.g. SIMULA-67, SL5, Interlisp, etc.). We say a language has block-structured coroutines (BSCRs) when static nesting considerations govern the usage o...Block-structured; BSCR1979
98 Pershing, David W.; Wendt, Jost O. L.Investigation of first- and second-stage variables on control of NOx emissions using staged combustion in a pulverized coal wall-fired furnaceRecent tests on an EPA 1- to 1.5 x 106 Btu/hr pilot-scale pulverized coal furnace show that N0X emissions of 100 ppm to 150 ppm (zero percent 02) are achievable with the use of two-stage combustion. Comparable N0X emission levels were obtained with three different coal types fired in either the sing...NOx; Carbon monoxide; Emissions1979
99 Frost, Richard L.High resolution astronomical imaging through the turbulent atmosphereThis research is principally concerned with the digital reconstruction of star images observed with large ground-based telescopes, although the techniques developed here will have application to a broad class of reconstruction problems. Since the work of Labeyrie, the difficulty in producing accurat...Astronomical imaging; Turbulent atmosphere; Digital reconstruction; Star images1979
100 Stringfellow, Gerald B.Electron mobility in AlxGa1-xAshe electron mobility in AlxGa1-xAs grown by several techniques has been studied to determine whether VPE layers are more highly compensated than comparable LPE layers. The techniques used to grow layers included (1) organometallic VPE using Al(CH3)3, AsH3, and Ga(C2H5)3 or Ga(CH3)3, (2) ''hybrid'' o...Alloys; Organometallics1979-06
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