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1

Matrix Operations  

NSDL National Science Digital Library

Created by Lewis Blake and David Smith of the Connected Curriculum Project, the purposes of this module are to experiment with matrix operations, especially multiplication, inversion, and determinants, and to explore applications to solving systems of linear equations. In the process of studying these matrix operations, we will learn how to use a helper application to carry out matrix computations.

Blake, Lewis; Smith, David

2010-06-24

2

Matrix Operations  

NSDL National Science Digital Library

Created by Lewis Blake and David Smith for the Connected Curriculum Project, the purposes of this module are to experiment with matrix operations, espcially multiplication, inversion, and determinants, and to explore applications to solving systems of linear equations. In the process of studying these matrix operations, we will learn how to use a helper application to carry out matrix computations. This is one of a much larger set of learning modules hosted by Duke University.

Blake, Lewis; Smith, David

2010-04-29

3

BASIC Matrix Operations.  

ERIC Educational Resources Information Center

The curriculum materials and computer programs in this booklet introduce the idea of a matrix. They go on to discuss matrix operations of addition, subtraction, multiplication by a scalar, and matrix multiplication. The last section covers several contemporary applications of matrix multiplication, including problems of communication…

Digital Equipment Corp., Maynard, MA.

4

Living Links: Applications of Matrix Operations to Population Studies  

NSDL National Science Digital Library

Many computational science models involve matrices. This module will provide a foundation for understanding matrices and some of their operations with examples from population dynamics and will provide background material for other computational science modules. The module will also have a discussion of the importance of matrices in many models that employ high performance computing. The model will have two accompanying tutorials. One will include some of the basics of MPI. The other will provide an introduction to matrices in Mathematica along with Grid Mathematica.

Angela B. Shiflet, George W. Shiflet, Jesse A. Hanley

5

Extension of radiative transfer code MOMO, matrix-operator model to the thermal infrared - Clear air validation by comparison to RTTOV and application to CALIPSO-IIR  

NASA Astrophysics Data System (ADS)

1-D radiative transfer code Matrix-Operator Model (MOMO), has been extended from [0.2-3.65 ?m] the band to the whole [0.2-100 ?m] spectrum. MOMO can now be used for the computation of a full range of radiation budgets (shortwave and longwave). This extension to the longwave part of the electromagnetic radiation required to consider radiative transfer processes that are features of the thermal infrared: the spectroscopy of the water vapor self- and foreign-continuum of absorption at 12 ?m and the emission of radiation by gases, aerosol, clouds and surface. MOMO?s spectroscopy module, Coefficient of Gas Absorption (CGASA), has been developed for computation of gas extinction coefficients, considering continua and spectral line absorptions. The spectral dependences of gas emission/absorption coefficients and of Planck?s function are treated using a k-distribution. The emission of radiation is implemented in the adding-doubling process of the matrix operator method using Schwarzschild?s approach in the radiative transfer equation (a pure absorbing/emitting medium, namely without scattering). Within the layer, the Planck-function is assumed to have an exponential dependence on the optical-depth. In this paper, validation tests are presented for clear air case studies: comparisons to the analytical solution of a monochromatic Schwarzschild?s case without scattering show an error of less than 0.07% for a realistic atmosphere with an optical depth and a blackbody temperature that decrease linearly with altitude. Comparisons to radiative transfer code RTTOV are presented for simulations of top of atmosphere brightness temperature for channels of the space-borne instrument MODIS. Results show an agreement varying from 0.1 K to less than 1 K depending on the channel. Finally MOMO results are compared to CALIPSO Infrared Imager Radiometer (IIR) measurements for clear air cases. A good agreement was found between computed and observed radiance: biases are smaller than 0.5 K and Root Mean Square Error (RMSE) varies between 0.4 K and 0.6 K depending on the channel. The extension of the code allows the utilization of MOMO as forward model for remote sensing algorithms in the full range spectrum. Another application is full range radiation budget computations (heating rates or forcings).

Doppler, Lionel; Carbajal-Henken, Cintia; Pelon, Jacques; Ravetta, François; Fischer, Jürgen

2014-09-01

6

A Method for Building Concept Lattice Based on Matrix Operation  

NASA Astrophysics Data System (ADS)

As a power tool for analyzing data, concept lattice has been extensively applied in several areas such as knowledge discovery, software engineering and case-based reasoning. However, building concept lattice is time-consuming and complicated; it becomes the bottleneck of application. Therefore, a simple and efficient method for building concept lattice is proposed in this paper. We transform binary formal context into matrix at first, and then discuss how to build concept lattice based on basic concepts and added concepts, which the two concepts can be got from matrix operation. We also present a fast algorithm BCLMO (Building Concept Lattice based on Matrix Operation) for building concept lattice, and analyze the time complexity of BCLMO. The method we proposed could remarkably reduce the time complexity and improve the efficiency of building concept lattice.

Li, Kai; Du, Yajun; Xiang, Dan; Chen, Honghua; Liao, Zhenwen

7

Remedial Action and Waste Disposal Conduct of OperationsMatrix  

SciTech Connect

This Conduct of Operations (CONOPS) matrix incorporates the Environmental Restoration Disposal Facility (ERDF) CONOPS matrix (BHI-00746, Rev. 0). The ERDF CONOPS matrix has been expanded to cover all aspects of the RAWD project. All remedial action and waste disposal (RAWD) operations, including waste remediation, transportation, and disposal at the ERDF consist of construction-type activities as opposed to nuclear power plant-like operations. In keeping with this distinction, the graded approach has been applied to the developmentof this matrix.

M. A. Casbon.

1999-05-24

8

Pathway fractional integral operator and matrix-variate functions  

Microsoft Academic Search

A general real matrix-variate pathway fractional integral operator is introduced here, which covers all the matrix-variate fractional integrals and almost all the extended densities for the pathway parameter ?<1 and ??1. Through this new fractional integral operator, one can go to matrix-variate gamma to matrix-variate Gaussian or normal density with appropriate parametric values. In the present paper, we bring out

Seema S. Nair

2011-01-01

9

Remedial Action and Waste Disposal Conduct of OperationsMatrix  

Microsoft Academic Search

This Conduct of Operations (CONOPS) matrix incorporates the Environmental Restoration Disposal Facility (ERDF) CONOPS matrix (BHI-00746, Rev. 0). The ERDF CONOPS matrix has been expanded to cover all aspects of the RAWD project. All remedial action and waste disposal (RAWD) operations, including waste remediation, transportation, and disposal at the ERDF consist of construction-type activities as opposed to nuclear power plant-like

M. A. Casbon

1999-01-01

10

Phase matrix induced symmetrics for multiple scattering using the matrix operator method  

NASA Technical Reports Server (NTRS)

Entirely rigorous proofs of the symmetries induced by the phase matrix into the reflection and transmission operators used in the matrix operator theory are given. Results are obtained for multiple scattering in both homogeneous and inhomogeneous atmospheres. These results will be useful to researchers using the method since large savings in computer time and storage are obtainable.

Hitzfelder, S. J.; Kattawar, G. W.

1973-01-01

11

Airspace Operations Demo Functional Requirements Matrix  

NASA Technical Reports Server (NTRS)

The Flight IPT assessed the reasonableness of demonstrating each of the Access 5 Step 1 functional requirements. The functional requirements listed in this matrix are from the September 2005 release of the Access 5 Functional Requirements Document. The demonstration mission considered was a notional Western US mission (WUS). The conclusion of the assessment is that 90% of the Access 5 Step 1 functional requirements can be demonstrated using the notional Western US mission.

2005-01-01

12

Application of Fuzzy Logic to Matrix FMECA  

NASA Astrophysics Data System (ADS)

A methodology combining the benefits of Fuzzy Logic and Matrix FMEA is presented in this paper. The presented methodology extends the risk prioritization beyond the conventional Risk Priority Number (RPN) method. Fuzzy logic is used to calculate the criticality rank. Also the matrix approach is improved further to develop a pictorial representation retaining all relevant qualitative and quantitative information of several FMEA elements relationships. The methodology presented is demonstrated by application to an illustrative example. .

Shankar, N. Ravi; Prabhu, B. S.

2001-04-01

13

On spectral properties of periodic polyharmonic matrix operators  

Microsoft Academic Search

We consider a matrix operatorH = (-?)l +V inR\\u000a n, wheren ? 2,l ? 1, 4l > n + 1, andV is the operator of multiplication by a periodic inx matrixV(x). We study spectral properties ofH in the high energy region. Asymptotic formulae for Bloch eigenvalues and the corresponding spectral projections are constructed.\\u000a The Bethe-Sommerfeld conjecture, stating that the spectrum

Yu E. Karpeshina

2002-01-01

14

Matrix elements of many-body operators and density correlations  

Microsoft Academic Search

The matrix element of a general many-body operator between two Slater determinants is calculated explicitly. For this, a split-and-pair method is introduced that provides a convenient expression of Wick's theorem and simplifies many-body calculations. The same method is used to determine the generating function of the matrix elements of many-body operators. The split-and-pair method allows also for the diagonalization of

Christian Brouder; Christian

2005-01-01

15

Metal Matrix Composite Materials for Aerospace Applications  

NASA Technical Reports Server (NTRS)

Metal matrix composites (MMC) are attractive materials for aerospace applications because of their high specific strength, high specific stiffness, and lower thermal expansion coefficient. They are affordable since complex parts can be produced by low cost casting process. As a result there are many commercial and Department of Defense applications of MMCs today. This seminar will give an overview of MMCs and their state-of-the-art technology assessment. Topics to be covered are types of MMCs, fabrication methods, product forms, applications, and material selection issues for design and manufacture. Some examples of current and future aerospace applications will also be presented and discussed.

Bhat, Biliyar N.; Jones, C. S. (Technical Monitor)

2001-01-01

16

Operational Models Matrix: Characteristics of Operational NWP Models  

NSDL National Science Digital Library

Characteristics of Operational NWP Models, part of the Numerical Weather Prediction Professional Development Series, contains information about the characteristics and architecture of commonly used operational models, their operationally significant strengths and weaknesses, and model assessment tools. The information is updated whenever significant model changes are made. The module is linked to the Impact of Model Numerics on Weather Depiction module (also in the NWP PDS), which provides background information about model components.

Spangler, Tim

2003-01-01

17

From nucleon-nucleon interaction matrix elements in momentum space to an operator representation  

NASA Astrophysics Data System (ADS)

Starting from the matrix elements of the nucleon-nucleon interaction in momentum space we present a method to derive an operator representation with a minimal set of operators that is required to provide an optimal description of the partial waves with low angular momentum. As a first application we use this method to obtain an operator representation for the Argonne potential transformed by means of the unitary correlation operator method and discuss the necessity of including momentum-dependent operators. The resulting operator representation leads to the same results as the original momentum space matrix elements when applied to the two-nucleon system and various light nuclei. For applications in fermionic and antisymmetrized molecular dynamics, where an operator representation of a soft but realistic effective interaction is indispensable, a simplified version using a reduced set of operators is given.

Weber, D.; Feldmeier, H.; Hergert, H.; Neff, T.

2014-03-01

18

Memory Efficient Parallel Matrix Multiplication Operation for Irregular Problems  

SciTech Connect

Regular distributions for storing dense matrices on parallel systems are not always used in practice. In many scientific applications, matrix distribution is based on the underlying physical problem and might involve variable block sizes on individual processors. This paper describes a generalization of the Shared and Remote-memory based Universal Matrix Multiplication Algorithm (SRUMMA) [1] to handle irregularly distributed matrices. Our approach relies on a distribution independent algorithm that provides dynamic load balancing by exploiting data locality and achieves performance as good as the traditional approach which relies on temporary arrays with regular distribution, data redistribution, and matrix multiplication for regular matrices to handle the irregular case. The proposed algorithm is memory-efficient because temporary matrices are not needed. This feature is critical for systems like the IBM Blue Gene/L that offer very limited amount of memory per node. The experimental results demonstrate very good performance across the range matrix distributions and problem sizes motivated by real applications.

Krishnan, Manoj Kumar; Nieplocha, Jarek

2006-05-03

19

Multiplier operator algebras and applications  

PubMed Central

The one-sided multipliers of an operator space X are a key to “latent operator algebraic structure” in X. We begin with a survey of these multipliers, together with several of the applications that they have had to operator algebras. We then describe several new results on one-sided multipliers, and new applications, mostly to one-sided M-ideals.

Blecher, David P.; Zarikian, Vrej

2004-01-01

20

Airbreathing Hypersonic Vision-Operational-Vehicles Design Matrix  

NASA Technical Reports Server (NTRS)

This paper presents the status of the airbreathing hypersonic airplane and space-access vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being, studied at Langley, it reflects the synergies and issues, and indicates the thrust of the effort to resolve the design matrix including Mach 5 to 10 airplanes with global-reach potential, pop-up and dual-role transatmospheric vehicles and airbreathing launch systems. The convergence of several critical systems/technologies across the vehicle matrix is indicated. This is particularly true for the low speed propulsion system for large unassisted horizontal takeoff vehicles which favor turbines and/or perhaps pulse detonation engines that do not require LOX which imposes loading concerns and mission Flexibility restraints.

Hunt, James L.; Pegg, Robert J.; Petley, Dennis H.

1999-01-01

21

Airbreathing Hypersonic Vision-Operational-Vehicles Design Matrix  

NASA Technical Reports Server (NTRS)

This paper presents the status of the airbreathing hypersonic airplane and space-access vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being studied at Langley; it reflects the synergies and issues, and indicates the thrust of the effort to resolve the design matrix including Mach 5 to 10 airplanes with global-reach potential, pop-up and dual-role transatmospheric vehicles and airbreathing launch systems. The convergence of several critical systems/technologies across the vehicle matrix is indicated. This is particularly true for the low speed propulsion system for large unassisted horizontal takeoff vehicles which favor turbines and/or perhaps pulse detonation engines that do not require LOX which imposes loading concerns and mission flexibility restraints.

Hunt, James L.; Pegg, Robert J.; Petley, Dennis H.

1999-01-01

22

Thermosetting Polymer-Matrix Composites for Structural Repair Applications.  

National Technical Information Service (NTIS)

Several classes of thermosetting polymer matrix composites were evaluated for use in structural repair applications. Initial work involved the characterization and evaluation of woven carbon fiber/epoxy matrix composites for structural pipeline repair. Cy...

D. Grewell M. Akinc M. R. Kessler W. K. Goertzen Z. Lin

2007-01-01

23

HPRR operating experience and applications  

SciTech Connect

The Health Physics Research Reactor (HPRR) is a small, unmoderated fast pulse reactor located at the Oak Ridge National Laboratory (ORNL). The HPRR is the principal research tool of ORNL's Dosimetry Applications Research (DOSAR) Group. The reactor is described, its operating experience is presented, and its major applications are discussed.

Bailiff, E.G.; Sims, C.S.; Swaja, R.E.

1986-01-01

24

Sharp Estimates in Ruelle Theorems for Matrix Transfer Operators  

NASA Astrophysics Data System (ADS)

A matrix coefficient transfer operator , on the space of -sections of an m-dimensional vector bundle over n-dimensional compact manifold is considered. The spectral radius of is estimated bya; and the essential spectral radius by Here is the set of ergodic f-invariant measures, and for is the measure-theoretic entropy of f, is the largest Lyapunov exponent of the cocycle over f generated by , and is the smallest Lyapunov exponent of the differential of f.

Campbell, J.; Latushkin, Y.

25

Fast Rectangular Matrix Multiplication and Applications  

Microsoft Academic Search

First we study asymptotically fast algorithms for rectangular matrix multiplication. We begin with new algorithms for multiplication of ann×nmatrix by ann×n2matrix in arithmetic timeO(n?),?=3.333953…, which is less by 0.041 than the previous record 3.375477…. Then we present fast multiplication algorithms for matrix pairs of arbitrary dimensions, estimate the asymptotic running time as a function of the dimensions, and optimize the

Xiaohan Huang; Victor Y. Pan

1998-01-01

26

Cloning operator and its applications  

NASA Astrophysics Data System (ADS)

A novel genetic operator called cloning is introduced and tested in different applications of genetic algorithms. Essentially, the cloning monotonically increases the lengths of the chromosomes during the evolution. It is argued that, under these circumstances, the cloning operator can accommodate a multiresolution search strategy, where the search starts at coarser scales and is subsequently mapped to finer scales upon achieving some in-scale performance criteria. Although the practical implementation of cloning is application dependent, a few general requirements are stated. In the remainder of the paper, different implementations of the cloning operator are introduced and employed in distinct applications, namely, function optimization, object support reconstruction from the support of its autocorrelation and the shortest path problem in planar graphs. The first two cases present typical multiresolution approaches to search problems and their results show consistent improvements in convergence speed with respect to classical genetic algorithms. In the last problem, a cloning operator is incorporated in an evolutionary algorithm that builds a set of valid paths in a planar graph. It is demonstrated that cloning can enhance the ability of a genetic algorithm to explore the search space efficiently in some applications.

Voicu, Liviu I.; Myler, Harley R.; Toma, Cristian E.

1998-03-01

27

General linear codes for fault-tolerant matrix operations on processor arrays  

NASA Technical Reports Server (NTRS)

Various checksum codes have been suggested for fault-tolerant matrix computations on processor arrays. Use of these codes is limited due to potential roundoff and overflow errors. Numerical errors may also be misconstrued as errors due to physical faults in the system. In this a set of linear codes is identified which can be used for fault-tolerant matrix operations such as matrix addition, multiplication, transposition, and LU-decomposition, with minimum numerical error. Encoding schemes are given for some of the example codes which fall under the general set of codes. With the help of experiments, a rule of thumb for the selection of a particular code for a given application is derived.

Nair, V. S. S.; Abraham, J. A.

1988-01-01

28

Dense and Sparse Matrix Operations on the Cell Processor  

SciTech Connect

The slowing pace of commodity microprocessor performance improvements combined with ever-increasing chip power demands has become of utmost concern to computational scientists. Therefore, the high performance computing community is examining alternative architectures that address the limitations of modern superscalar designs. In this work, we examine STI's forthcoming Cell processor: a novel, low-power architecture that combines a PowerPC core with eight independent SIMD processing units coupled with a software-controlled memory to offer high FLOP/s/Watt. Since neither Cell hardware nor cycle-accurate simulators are currently publicly available, we develop an analytic framework to predict Cell performance on dense and sparse matrix operations, using a variety of algorithmic approaches. Results demonstrate Cell's potential to deliver more than an order of magnitude better GFLOP/s per watt performance, when compared with the Intel Itanium2 and Cray X1 processors.

Williams, Samuel W.; Shalf, John; Oliker, Leonid; Husbands,Parry; Yelick, Katherine

2005-05-01

29

Matrix operator theory of radiative transfer. I - Rayleigh scattering.  

NASA Technical Reports Server (NTRS)

An entirely rigorous method for the solution of the equations for radiative transfer based on the matrix operator theory is reviewed. The advantages of the present method are: (1) all orders of the reflection and transmission matrices are calculated at once; (2) layers of any thickness may be combined, so that a realistic model of the atmosphere can be developed from any arbitrary number of layers, each with different properties and thicknesses; (3) calculations can readily be made for large optical depths and with highly anisotropic phase functions; (4) results are obtained for any desired value of the surface albedo including the value unity and for a large number of polar and azimuthal angles; (5) all fundamental equations can be interpreted immediately in terms of the physical interactions appropriate to the problem; and (6) both upward and downward radiance can be calculated at interior points from relatively simple expressions.

Plass, G. N.; Kattawar, G. W.; Catchings, F. E.

1973-01-01

30

DSP-Based Matrix Converter Operation Under Various Abnormal Conditions with Practicality  

Microsoft Academic Search

The matrix converter connects the three phase power supply with the three phase load directly through a switching matrix composed of four-quadrant switches. The operation of matrix converter with unbalanced power supply has been analyzed. For this, a 230 V, 250 VA three phase to three phase matrix converter prototype is implemented using DSP based controller and tests have been

V. Kumar; R. R. Joshi

2006-01-01

31

IMSL and Matrix Signatures of Quantum Mechanical Operators in the Rayleigh-Ritz-Galerkin Method  

NASA Astrophysics Data System (ADS)

A central issue in many applications of quantum mechanics is the solution of a wave equation to find the energy eigenvalues and eigenfunctions. An alternative to the standard procedure of numerical solutions is the Rayleigh-Ritz-Galerkin method, where the wave function is expanded in terms of a complete set of basis functions. Then the eigenvalue problem reduces to that of diagonalizing a Hamiltonian matrix. An efficient basis for many three-dimensional bound state problems is a radial function that combines an exponential confining factor, an angular momentum barrier factor and a Laguerre polynomial. Then analytic expressions can be found for the linear and Coulomb potential energy matrix elements and the matrix elements of the square of the momentum operator. The range of applications is expanded considerably by using certain algorithms to compute representatives of additional operators from characteristic signatures of these basic matrices. Several examples will be presented. Applications to nonlocal relativistic wave equations, for which the standard numerical techniques of second-order differential equations do not apply, will also be considered.

Fulcher, L. P.

1997-05-01

32

Structural and functional polymer-matrix composites for electromagnetic applications  

Microsoft Academic Search

This dissertation addresses the science and technology of functional and structural polymer-matrix composite materials for electromagnetic applications, which include electromagnetic interference (EMI) shielding and low observability (Stealth). The structural composites are continuous carbon fiber epoxy-matrix composites, which are widely used for airframes. The functional composites are composites with discontinuous fillers and in both bulk and coating forms. Through composite structure

Junhua Wu

2010-01-01

33

Matrix genetics, part 5: genetic projection operators and direct sums  

Microsoft Academic Search

The article is devoted to phenomena of symmetries and algebras in matrix presentations of the genetic code. The Kronecker family of the genetic matrices is investigated, which is based on the alphabetical matrix [C A; U G], where C, A, U, G are the letters of the genetic alphabet. The matrix P=[C A; U G] in the third Kronecker power

Sergey V. Petoukhov

2010-01-01

34

Application of Photorefractive Crystals to Solve Matrix Algebra Problems Optically.  

National Technical Information Service (NTIS)

The goals for the project are to solve matrix algebraic problems at high speed by applying photorefractive crystals in optical processing systems, and to study the photorefractives for such application. Although our interest was primarily on solving matri...

S. H. Lee

1992-01-01

35

Graphite fiber reinforced glass matrix composites for aerospace applications  

NASA Technical Reports Server (NTRS)

The graphite fiber reinforced glass matrix composite system is described. Although this composite is not yet a mature material, it possesses low density, attractive mechanical properties at elevated temperatures, and good environmental stability. Properties are reported for a borosilicate glass matrix unidirectionally reinforced with 60 volume percent HMS graphite fiber. The flexural strength and fatigue characteristics at room and elevated temperature, resistance to thermal cycling and continuous high temperature oxidation, and thermal expansion characteristics of the composite are reported. The properties of this new composite are compared to those of advanced resin and metal matrix composites showing that graphite fiber reinforced glass matrix composites are attractive for aerospace applications.

Prewo, K. M.; Bacon, J. F.; Dicus, D. L.

1979-01-01

36

Effect of Witch Configuration on the Operation of a Switch Matrix.  

National Technical Information Service (NTIS)

In a series of 3 experiments the speed and accuracy of switch-matrix operations were determined for 5 different matrix configurations. Factors influencing performance included switch orientation (whether row or column), reach distance, and the type of sym...

R. S. Lincoln S. A. Konz

1965-01-01

37

Maintainability Applications Using the Matrix FMEA Technique  

Microsoft Academic Search

The Matrix Method of Failure Modes and Effects Analysis (FMEA) provides an organized and traceable analysis from the piece-part failure-mode through all indenture levels to system-level failure effects. This paper describes a methodology for reversing the buildup process for maintainability analysis. The output of this reverse process identifies each system-failure effect individually and the related indentured, lower-level composition of contributing

Stephanie A. Herrin

1981-01-01

38

Exact effective Hamiltonian theory. II. Polynomial expansion of matrix functions and entangled unitary exponential operators.  

PubMed

Our recent exact effective Hamiltonian theory (EEHT) for exact analysis of nuclear magnetic resonance (NMR) experiments relied on a novel entanglement of unitary exponential operators via finite expansion of the logarithmic mapping function. In the present study, we introduce simple alternant quotient expressions for the coefficients of the polynomial matrix expansion of these entangled operators. These expressions facilitate an extension of our previous closed solution to the Baker-Campbell-Hausdorff problem for SU(N) systems from N< or =4 to any N, and thereby the potential application of EEHT to more complex NMR spin systems. Similarity matrix transformations of the EEHT expansion are used to develop alternant quotient expressions, which are fully general and prove useful for evaluation of any smooth matrix function. The general applicability of these expressions is demonstrated by several examples with relevance for NMR spectroscopy. The specific form of the alternant quotients is also used to demonstrate the fundamentally important equivalence of Sylvester's theorem (also known as the spectral theorem) and the EEHT expansion. PMID:15267261

Siminovitch, David; Untidt, Thomas; Nielsen, Niels Chr

2004-01-01

39

An advanced algorithm for construction of Integral Transport Matrix Method operators using accumulation of single cell coupling factors  

SciTech Connect

The Integral Transport Matrix Method (ITMM) has been shown to be an effective method for solving the neutron transport equation in large domains on massively parallel architectures. In the limit of very large number of processors, the speed of the algorithm, and its suitability for unstructured meshes, i.e. other than an ordered Cartesian grid, is limited by the construction of four matrix operators required for obtaining the solution in each sub-domain. The existing algorithm used for construction of these matrix operators, termed the differential mesh sweep, is computationally expensive and was developed for a structured grid. This work proposes the use of a new algorithm for construction of these operators based on the construction of a single, fundamental matrix representing the transport of a particle along every possible path throughout the sub-domain mesh. Each of the operators is constructed by multiplying an element of this fundamental matrix by two factors dependent only upon the operator being constructed and on properties of the emitting and incident cells. The ITMM matrix operator construction time for the new algorithm is demonstrated to be shorter than the existing algorithm in all tested cases with both isotropic and anisotropic scattering considered. While also being a more efficient algorithm on a structured Cartesian grid, the new algorithm is promising in its geometric robustness and potential for being applied to an unstructured mesh, with the ultimate goal of application to an unstructured tetrahedral mesh on a massively parallel architecture. (authors)

Powell, B. P.; Azmy, Y. Y. [North Carolina State University, Department of Nuclear Engineering, Burlington Engineering Labs, 2500 Stinston Drive, Raleigh, NC 27695 (United States)] [North Carolina State University, Department of Nuclear Engineering, Burlington Engineering Labs, 2500 Stinston Drive, Raleigh, NC 27695 (United States)

2013-07-01

40

Matrix multiplication operations with data pre-conditioning in a high performance computing architecture  

SciTech Connect

Mechanisms for performing matrix multiplication operations with data pre-conditioning in a high performance computing architecture are provided. A vector load operation is performed to load a first vector operand of the matrix multiplication operation to a first target vector register. A load and splat operation is performed to load an element of a second vector operand and replicating the element to each of a plurality of elements of a second target vector register. A multiply add operation is performed on elements of the first target vector register and elements of the second target vector register to generate a partial product of the matrix multiplication operation. The partial product of the matrix multiplication operation is accumulated with other partial products of the matrix multiplication operation.

Eichenberger, Alexandre E; Gschwind, Michael K; Gunnels, John A

2013-11-05

41

MAAP nuclear operations support applications  

SciTech Connect

This paper discusses some applications of the modular accident analysis program (both MAAP3 and MAAP4) at the Pacific Gas & Electric Company (PG&E). MAAP is used to analyze the twin-unit Diablo Canyon nuclear power plant (DCPP). DCPP has two four-loop Westinghouse pressurized water reactors (PWRs). Although MAAP was extensively used to support the individual plant examination for DCPP and it is being used to support the development of a plant-specific severe accident management program, MAAP has also been a very useful tool in the areas of postevent analysis, engineering support, and operations support. This paper presents some examples of the use of MAAP in all these areas: the so-called non-severe-accident areas.

Dion, D.R. [Pacific Gas & Electric Co., San Francisco, CA (United States)

1996-12-31

42

Fluctuation studies on the finite interval matrix representations of operator products and their decompositions  

NASA Astrophysics Data System (ADS)

In this work an experimental study on finite dimensional matrix approximations to products of various operators under a basis set orthonormalized on a finite interval is conducted. The elements of the matrices corresponding to the matrix representation of various operators, are calculated based on various term recursive relations. It is shown that higher the values of n, lower the relative marginal change will be obtained from the norm of the difference of the matrix representation of a product of two operators and the product of the matrix representations of the same operators.

Gürvit, Ercan; Baykara, N. A.; Demiralp, Metin

2012-12-01

43

Real-number codes for fault-tolerant matrix operations on processor arrays  

NASA Technical Reports Server (NTRS)

A generalization of existing real number codes is proposed. It is proven that linearity is a necessary and sufficient condition for codes used for fault-tolerant matrix operations such as matrix addition, multiplication, transposition, and LU decomposition. It is also proven that for every linear code defined over a finite field, there exists a corresponding linear real-number code with similar error detecting capabilities. Encoding schemes are given for some of the example codes which fall under the general set of real-number codes. With the help of experiments, a rule is derived for the selection of a particular code for a given application. The performance overhead of fault tolerance schemes using the generalized encoding schemes is shown to be very low, and this is substantiated through simulation experiments.

Nair, V. S. S.; Abraham, Jacob A.

1990-01-01

44

Matrix elements of two-body operators between many-body symmetrized hyperspherical states  

Microsoft Academic Search

Matrix elements of two-body operators between many-particle permutational symmetry-adapted functions in hyperspherical coordinates are constructed. The matrix elements are evaluated using the appropriate hyperspherical coefficients of fractional parentage, the Raynal-Revai coefficients, and the hyperspherical recoupling coefficients. We use the power expansion of the two-body operators and obtain an analytic expression for the matrix element of each term. These expressions are

Akiva Novoselsky; Nir Barnea

1995-01-01

45

Matrix transfer function design for flexible structures: An application  

NASA Technical Reports Server (NTRS)

The application of matrix transfer function design techniques to the problem of disturbance rejection on a flexible space structure is demonstrated. The design approach is based on parameterizing a class of stabilizing compensators for the plant and formulating the design specifications as a constrained minimization problem in terms of these parameters. The solution yields a matrix transfer function representation of the compensator. A state space realization of the compensator is constructed to investigate performance and stability on the nominal and perturbed models. The application is made to the ACOSSA (Active Control of Space Structures) optical structure.

Brennan, T. J.; Compito, A. V.; Doran, A. L.; Gustafson, C. L.; Wong, C. L.

1985-01-01

46

Design of RF MEMS based switch matrix for space applications  

NASA Astrophysics Data System (ADS)

RF MEMS based switch matrices have several advantages compared to the mechanical or solid-state switch based ones for space applications. They are compact, light and less lossy with a high linearity up to high frequency. In this work, a 12 × 12 switch matrix with RF MEMS and LTCC technologies is presented based on the planar Beneš network. The simulated performance of the 12 × 12 switch matrix is below -12 dB IL (Insertion Loss) up to C band and -15 dB RL (Return Loss) up to Ku band. Moreover, it has a good isolation better than -50 dB. A 4 × 4 switch matrix with the same design process and technologies is fabricated and measured to verify the 12 × 12 switch matrix design process. The measured performance agrees very well to the simulations.

Di Nardo, S.; Farinelli, P.; Kim, T.; Marcelli, R.; Margesin, B.; Paola, E.; Pochesci, D.; Vietzorreck, L.; Vitulli, F.

2013-07-01

47

On Krylov Subspace Approximations To The Matrix Exponential Operator  

Microsoft Academic Search

. Krylov subspace methods for approximating the action of matrix exponentials areanalyzed in this paper. We derive error bounds via a functional calculus of Arnoldi and Lanczosmethods that reduces the study of Krylov subspace approximations of functions of matrices to thatof linear systems of equations. As a side result, we obtain error bounds for Galerkin-type Krylovmethods for linear equations, namely

Marlis Hochbruck; Christian Lubich

1996-01-01

48

Polymer, metal and ceramic matrix composites for advanced aircraft engine applications  

NASA Technical Reports Server (NTRS)

Advanced aircraft engine research within NASA Lewis is being focused on propulsion systems for subsonic, supersonic, and hypersonic aircraft. Each of these flight regimes requires different types of engines, but all require advanced materials to meet their goals of performance, thrust-to-weight ratio, and fuel efficiency. The high strength/weight and stiffness/weight properties of resin, metal, and ceramic matrix composites will play an increasingly key role in meeting these performance requirements. At NASA Lewis, research is ongoing to apply graphite/polyimide composites to engine components and to develop polymer matrices with higher operating temperature capabilities. Metal matrix composites, using magnesium, aluminum, titanium, and superalloy matrices, are being developed for application to static and rotating engine components, as well as for space applications, over a broad temperature range. Ceramic matrix composites are also being examined to increase the toughness and reliability of ceramics for application to high-temperature engine structures and components.

Mcdanels, D. L.; Serafini, T. T.; Dicarlo, J. A.

1985-01-01

49

Matrix operator approach to the quantum evolution operator and the geometric phase  

NASA Astrophysics Data System (ADS)

The Moody-Shapere-Wilczek's adiabatic effective Hamiltonian and Lagrangian method is developed further into the matrix effective Hamiltonian (MEH) and Lagrangian (MEL) approach to a parameter-dependent quantum system. The matrix-operator approach formulated in the product integral (PI) provides not only a method to find the wave function efficiently in the MEH approach but also higher order corrections to the effective action systematically in the MEL approach, a la the Magnus expansion and the Kubo cumulant expansion. A coupled quantum system of a light particle of a harmonic oscillator is worked out, and as a by-product, a new kind of gauge potential (Berry's connection) is found even for nondegenerate cases (real eigenfunctions). Moreover, in the PI formulation the holonomy of the induced gauge potential is related to Schlesinger's exact formula for the gauge field tensor. A superadiabatic expansion is also constructed, and a generalized Dykhne formula, depending on the contour integrals of the homotopy class of complex degenerate points, is rephrased in the PI formulation.

Kim, Sang Pyo; Kim, Jewan; Soh, Kwang Sup

2013-11-01

50

Aluminum Metal-Matrix Composites for Automotive Applications: Tribological Considerations  

Microsoft Academic Search

Aluminum alloys possess a number of mechanical and physical properties that make them attractive for automotive applications, but they exhibit extremely poor resistance to seizure and galling. Reinforcement of aluminum alloys with solid lubricants, hard ceramic particles, short fibers and whiskers results in advanced metal-matrix composites (MMC) with precise balances of mechanical, physical and tribological characteristics. Advanced manufacturing technologies such

S. V. Prasad; R. Asthana

2004-01-01

51

Enamel matrix proteins; old molecules for new applications  

PubMed Central

Emdogain® (enamel matrix derivative, EMD) is well recognized in periodontology, where it is used as a local adjunct to periodontal surgery to stimulate regeneration of periodontal tissues lost to periodontal disease. The biological effect of EMD is through stimulation of local growth factor secretion and cytokine expression in the treated tissues, inducing a regenerative process that mimics odontogenesis. The major (>95%) component of EMD is Amelogenins (Amel). No other active components have so far been isolated from EMD, and several studies have shown that purified amelogenins can induce the same effect as the complete EMD. Amelogenins comprise a family of highly conserved extracellular matrix proteins derived from one gene. Amelogenin structure and function is evolutionary well conserved, suggesting a profound role in biomineralization and hard tissue formation. A special feature of amelogenins is that under physiological conditions the proteins self-assembles into nanospheres that constitute an extracellular matrix. In the body, this matrix is slowly digested by specific extracellular proteolytic enzymes (matrix metalloproteinase) in a controlled process, releasing bioactive peptides to the surrounding tissues for weeks after application. Based on clinical and experimental observations in periodontology indicating that amelogenins can have a significant positive influence on wound healing, bone formation and root resorption, several new applications for amelogenins have been suggested. New experiments now confirm that amelogenins have potential for being used also in the fields of endodontics, bone regeneration, implantology, traumatology, and wound care.

Lyngstadaas, S.P.; Wohlfahrt, J.C.; Brookes, S.J.; Paine, M.L.; Snead, M.L.; Reseland, J.E.

2010-01-01

52

A Linear Array for Large Sparse Matrix Operations - Ii Triangular System Solvers and Matrix Multiplication  

Microsoft Academic Search

Two triangular system solvers, one for the lower triangular system and the other for the upper triangular system, are developed and implemented on the linear array. Tests conducted with respect to these two solvers reveal that the performance of the backward solver is better than that of the forward solver. The matrix multiplication routine that is implemented on the linear

M. V. Padmini; B. B. Madan; Bijendra N. Jain

1999-01-01

53

A solvent-free matrix application method for matrix-assisted laser desorption/ionization imaging of small molecules.  

PubMed

Matrix application continues to be a critical step in sample preparation for matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI). Imaging of small molecules such as drugs and metabolites is particularly problematic because the commonly used washing steps to remove salts are usually omitted as they may also remove the analyte, and analyte spreading is more likely with conventional wet matrix application methods. We have developed a method which uses the application of matrix as a dry, finely divided powder, here referred to as dry matrix application, for the imaging of drug compounds. This appears to offer a complementary method to wet matrix application for the MALDI-MSI of small molecules, with the alternative matrix application techniques producing different ion profiles, and allows the visualization of compounds not observed using wet matrix application methods. We demonstrate its value in imaging clozapine from rat kidney and 4-bromophenyl-1,4-diazabicyclo(3.2.2)nonane-4-carboxylic acid from rat brain. In addition, exposure of the dry matrix coated sample to a saturated moist atmosphere appears to enhance the visualization of a different set of molecules. PMID:20486266

Goodwin, R J; Macintyre, L; Watson, D G; Scullion, S P; Pitt, A R

2010-06-15

54

A matrix safety frame approach to robot safety for space applications. Thesis  

NASA Technical Reports Server (NTRS)

The planned use of autonomous robots in space applications has generated many new safety problems. This thesis assesses safety of autonomous robot systems through the structure of a proposed three-dimensional matrix safety frame. By identifying the common points of accidents and fatalities involving terrestrial robots, reviewing terrestrial robot safety standards, and modifying and extending these results to space applications, hazards are identified and their associated risks assessed. Three components of the safeguarding dimension of the matrix safety frame, safeguarding through design and operation for intrinsic safety, and incorporation of add-on safety systems are explained through examples for both terrestrial and space robots. A space robot hazard identification checklist, a qualitative tool for robot systems designers, is developed using the structure imparted by the matrix safety frame. The development of an expert system from the contents of the checklist is discussed.

Montgomery, T. D.; Lauderbaugh, L. Ken

1988-01-01

55

Examining Operational Measures of Performance: Performance Measures Matrix.  

National Technical Information Service (NTIS)

An investigation was conducted, of current methods and procedures used by the operational Air Force. to gather data relevant to individual job performance. The usefulness of these methods and procedures was evaluated, in terms of their utility for collect...

B. L. Elder L. A. Hansen D. L. Harville

1992-01-01

56

The universal R-matrix and factorization of the L-operators related to the Baxter Q-operators  

NASA Astrophysics Data System (ADS)

We consider the ‘universal monodromy operators’ for the Baxter Q-operators. They are given as images of the universal R-matrix in oscillator representation. We find related universal factorization formulas in the U_{q}(\\hat{sl}(2)) case.

Khoroshkin, Sergey; Tsuboi, Zengo

2014-05-01

57

Applications of the optoelectronic matrix switch to communication systems  

NASA Astrophysics Data System (ADS)

Because of their potential applications to satellite and other broadband switching systems, wideband matrix switches employing optical signal distribution and optoelectronic devices at the crosspoints have recently received considerable attention. Crosspoint isolation of more than 80 dB at signal frequencies up to 1 GHz and over 50 dB up to 4 GHz has been demonstrated with a silicon photodiode performing the switching. High speed switching with transition times less than 5 ns has also been demonstrated with GaAs devices. An optoelectronic matrix switch based on heterojunction photodiodes has been constructed for switching 400 Mb/s NRZ signals and a matrix switch for 10 MHz to 100 MHz signals is being developed commercially. With their features of high isolation, high crosstalk loss and short transition times, optoelectronic matrix switches lend themselves well to applications in satellite switched time division multiple-access (SS/TDMA) communication systems and the distribution of centrally-switched TV signals to subscribers in a fiber optic integrated service system.

Hara, E. H.; MacDonald, R. I.; Hum, R. H.

58

MAAP nuclear operations support applications  

Microsoft Academic Search

This paper discusses some applications of the modular accident analysis program (both MAAP3 and MAAP4) at the Pacific Gas & Electric Company (PG&E). MAAP is used to analyze the twin-unit Diablo Canyon nuclear power plant (DCPP). DCPP has two four-loop Westinghouse pressurized water reactors (PWRs). Although MAAP was extensively used to support the individual plant examination for DCPP and it

Dion

1996-01-01

59

Matrix elements of one-body and two-body operators between arbitrary HFB multi-quasiparticle states  

NASA Astrophysics Data System (ADS)

We present new formulae for the matrix elements of one-body and two-body physical operators, which are applicable to arbitrary Hartree-Fock-Bogoliubov wave functions, including those for multi-quasiparticle excitations. The testing calculations show that our formulae may substantially reduce the computational time by several orders of magnitude when applied to many-body quantum system in a large Fock space.

Hu, Qing-Li; Gao, Zao-Chun; Chen, Y. S.

2014-06-01

60

The Resultant Matrix and its Generalizations. I. The Resultant Operator for Matrix Polynomials  

Microsoft Academic Search

\\u000a Let a(?)=a\\u000a 0+a\\u000a 1?+ ... +a\\u000a \\u000a n\\u000a ?\\u000a n\\u000a and b(?)=b\\u000a 0+b\\u000a 1?+ ... +b\\u000a \\u000a m\\u000a ?\\u000a m\\u000a be two polynomials with coefficients in ?1. The determinant of the following matrix \\u000a \\u000a \\u000a \\u000a \\u000a \\u000a \\u000a \\u000a is said to be the resultant of these polynomials.

Israel Gohberg; Georg Heinig

61

Unity Power Factor Operation Control Method For Single-phase to Three-phase Matrix Converter  

NASA Astrophysics Data System (ADS)

This paper proposes a new control method of matrix converter to obtain the unity power factor operation. Source side of the matrix converter is single-phase voltage, and the load side is three-phase ac motor. The number of switching device is six, and the converter does not require a reactor or an electrolytic capacitor. Generally, it is difficult for matrix converter to control both its input current waveform and the output voltage waveform, because the switching devices are connected to both source side and load side. In this paper, applying an algebraic transfer matrix, the control method of single-phase to three-phase matrix converter applies the indirect modulation model. The indirect modulation model treats a matrix converter as a two-stage transformation converter. The rectifier of proposed model consists only diode and small L-C filter. Hence, the switching frequency is lower than the conventional model one. The inverter of the proposed model regulates both the input current waveform and the motor speed. The inverter control scheme for IPM motor is based on direct torque control (DTC). The additional current controller improves its input current waveform. Hence, an optimum switching pattern of the matrix converter realizes quick torque response and unity power factor operation. This paper describes that the proposed method achieves the power factor 97.6% by experimental tests. The experimental results confirm the feasibility of the proposed method for matrix converter.

Haga, Hitoshi; Takahashi, Isao; Ohishi, Kiyoshi

62

Implementation Challenges for Ceramic Matrix Composites in High Temperature Applications  

NASA Technical Reports Server (NTRS)

Ceramic matrix composites are leading candidate materials for a number of applications in aeronautics, space, energy, electronics, nuclear, and transportation industries. In the aeronautics and space exploration systems, these materials are being considered for applications in hot sections of jet engines such as the combustor liner, nozzle components, nose cones, leading edges of reentry vehicles and space propulsion components. Applications in the energy and environmental industries include radiant heater tubes, heat exchangers, heat recuperators, gas and diesel particulate filters (DPFs), and components for land based turbines for power generation. These materials are also being considered for use in the first wall and blanket components of fusion reactors. There are a number of critical issues and challenges related to successful implementation of composite materials. Fabrication of net and complex shape components with high density and tailorable matrix properties is quite expensive, and even then various desirable properties are not achievable. In this presentation, microstructure and thermomechanical properties of composites fabricated by two techniques (chemical vapor infiltration and melt infiltration), will be presented. In addition, critical need for robust joining and assembly technologies in successful implementation of these systems will be discussed. Other implementation issues will be discussed along with advantages and benefits of using these materials for various components in high temperature applications.

Singh, Mrityunjay

2004-01-01

63

Advanced Ceramic Matrix Composites (CMCs) for High Temperature Applications  

NASA Technical Reports Server (NTRS)

Advanced ceramic matrix composites (CMCs) are enabling materials for a number of demanding applications in aerospace, energy, and nuclear industries. In the aerospace systems, these materials are being considered for applications in hot sections of jet engines such as the combustor liner, vanes, nozzle components, nose cones, leading edges of reentry vehicles, and space propulsion components. Applications in the energy and environmental industries include radiant heater tubes, heat exchangers, heat recuperators, gas and diesel particulate filters, and components for land based turbines for power generation. These materials are also being considered for use in the first wall and blanket components of fusion reactors. In the last few years, a number of CMC components have been developed and successfully tested for various aerospace and ground based applications. However, a number of challenges still remain slowing the wide scale implementation of these materials. They include robust fabrication and manufacturing, assembly and integration, coatings, property modeling and life prediction, design codes and databases, repair and refurbishment, and cost. Fabrication of net and complex shape components with high density and tailorable matrix properties is quite expensive, and even then various desirable properties are not achievable. In this presentation, a number of examples of successful CMC component development and testing will be provided. In addition, critical need for robust manufacturing, joining and assembly technologies in successful implementation of these systems will be discussed.

Singh, M.

2005-01-01

64

Matrix elements and few-body calculations within the unitary correlation operator method  

Microsoft Academic Search

We employ the unitary correlation operator method (UCOM) to construct correlated, low-momentum matrix elements of realistic nucleon-nucleon interactions. The dominant short-range central and tensor correlations induced by the interaction are included explicitly by an unitary transformation. Using correlated momentum-space matrix elements of the Argonne V18 potential, we show that the unitary transformation eliminates the strong off-diagonal contributions caused by the

R. Roth; H. Hergert; P. Papakonstantinou; T. Neff; H. Feldmeier

2005-01-01

65

Metal matrix composite processing technologies for aircraft engine applications  

Microsoft Academic Search

Titanium metal-matrix composites (MMC) are prime candidate materials for aerospace applications be-cause of their excellent\\u000a high-temperature longitudinal strength and stiffness and low density compared with nickel- and steel-base materials. This\\u000a article examines the steps GE Aircraft Engines (GEAE) has taken to develop an induction plasma deposition (IPD) processing\\u000a method for the fabrication of Ti6242\\/SiC MMC material. Information regarding process methodology,

D. R. Pank; J. J. Jackson

1993-01-01

66

Carbon matrix based magnetic nanocomposites for potential biomedical applications.  

PubMed

It was found that by varying the pyrolysis temperature of the polymeric precursor, carbon matrix magnetic nanocomposites with different constitution and fractions of magnetic component were made. X-ray diffraction, transmission electron microscopy and Raman spectroscopy revealed the presence of nanocrystallites (NCs) of Co, Fe3C and Ni embedded in porous, partially-graphitized carbon matrix. Vibrating sample magnetometer measurements enabled to determine the correlation between NCs size distribution and magnetic properties. The magnetic studies confirmed that the coercivity, saturation and remanent magnetizations, as well as fraction of the magnetic component depend on the pyrolysis temperature. The Co#C and Fe3C#C composites exhibited ferromagnetic behavior with a remanent to saturation magnetization (M(R)/M(S)) ratio ranging from 0.25 to 0.3, whereas in the Ni containing samples a relatively small M(R)/M(S) ratio point to significant contribution of superparamagnetic interactions. As the carbon matrix magnetic nanocomposites are proposed for biomedical application the basic cytotoxicity test were performed to evaluate a potential toxic effect of the materials on MG-63 cells line. PMID:24745221

Izydorzak-Wozniak, M; Leonowicz, M

2014-03-01

67

Erosion Resistant Coatings for Polymer Matrix Composites in Propulsion Applications  

NASA Technical Reports Server (NTRS)

Polymer Matrix Composites (PMCs) offer lightweight and frequently low cost alternatives to other materials in many applications. High temperature PMCs are currently used in limited propulsion applications replacing metals. Yet in most cases, PMC propulsion applications are not in the direct engine flow path since particulate erosion degrades PMC component performance and therefore restricts their use in gas turbine engines. This paper compares two erosion resistant coatings (SANRES and SANPRES) on PMCs that are useful for both low and high temperature propulsion applications. Collaborating over a multi-year period, researchers at NASA Glenn Research Center, Allison Advanced Developed Company, and Rolls-Royce Corporation have optimized these coatings in terms of adhesion, surface roughness, and erosion resistance. Results are described for vigorous hot gas/particulate erosion rig and engine testing of uncoated and coated PMC fan bypass vanes from the AE 3007 regional jet gas turbine engine. Moreover, the structural durability of these coatings is described in long-term high cycle fatigue tests. Overall, both coatings performed well in all tests and will be considered for applications in both commercial and defense propulsion applications.

Sutter, James K.; Naik, Subhash K.; Horan, Richard; Miyoshi, Kazuhisa; Bowman, Cheryl; Ma, Kong; Leissler, George; Sinatra, Raymond; Cupp, Randall

2003-01-01

68

Diagonal multi-matrix correlators and BPS operators in Script N = 4 SYM  

NASA Astrophysics Data System (ADS)

We present a complete basis of multi-trace multi-matrix operators that has a diagonal two point function for the free matrix field theory at finite N. This generalises to multiple matrices the single matrix diagonalisation by Schur polynomials. Crucially, it involves intertwining the gauge group U(N) and the global symmetry group U(M) with Clebsch-Gordan coefficients of symmetric groups Sn. When applied to Script N = 4 super Yang-Mills we consider the U(3) subgroup of the full symmetry group. The diagonalisation allows the description of a dual basis to multi-traces, which permits the characterisation of the metric on operators transforming in short representations at weak coupling. This gives a framework for the comparison of quarter and eighth-BPS giant gravitons of AdS5 × S5 spacetime to gauge invariant operators of the dual Script N = 4 SYM.

Brown, T. W.; Heslop, P. J.; Ramgoolam, S.

2008-02-01

69

INR proton Linac operation and applications  

NASA Astrophysics Data System (ADS)

The INR Proton Linear Accelerator is presently under operation for about 2400 h per year with energy about 250 MeV and average current up to 150 ?A. The Linac applications are mainly as follows: neutron and condensed matter research at spallation neutron source and neutron spectrometers, isotope production for medicine and industry, beam therapy. The experimental area description and the Linac operational experience are given in the paper.

Kravchuk, Leonid V.

2006-06-01

70

An Application of Matrix Sampling to the Method of Pair Comparisons  

ERIC Educational Resources Information Center

The use of matrix sampling to overcome the impracticality of the pair comparison method for obtaining scale values is empirically tested. Results indicate that matrix sampling is useful in such applications. (Author/JKS)

Olson, Margot A.

1978-01-01

71

Theory and application of radiation boundary operators  

NASA Technical Reports Server (NTRS)

A succinct unified review is provided of the theory of radiation boundary operators. With the recent introduction of the on-surface radiation condition (OSRC) method and the continued growth of finite-difference and finite-element techniques for modeling electromagnetic wave scattering problems, the understanding and use of radiation boundary operators has become increasingly important. Results are presented to illustrate the application of radiation boundary operators in both these areas. Recent OSRC results include analysis of the scattering behavior of both electrically small and large cylinders, a reactively loaded acoustic sphere, and a simple reentrant duct. Radiation boundary operator results include the demonstration of the effectiveness of higher-order operators in truncating finite-difference time-domain grids.

Moore, Thomas G.; Kriegsmann, Gregory A.; Taflove, Allen; Blaschak, Jeffrey G.

1988-01-01

72

The most general L operator for the R -matrix of the XXX model  

Microsoft Academic Search

The problem of describing all the monodromy matrices for R matrices of the XXX and XXZ models is discussed. It is shown that the L operator of the lattice nonlinear Schrödinger model generates all possible monodromy matrices for the XXX R matrix.

A. G. Izergin; V. E. Korepin

1984-01-01

73

Operational Experience with the Scattering Matrix Arc Detection System on the JET ITER-Like Antenna  

Microsoft Academic Search

The Scattering Matrix Arc Detection System (SMAD) has been fully deployed on all 4 sets of Resonant Double Loop (RDL), Vacuum Transmission Line (VTL) and Antenna Pressurised Transmission Lines (APTL) of the JET ICRF ITER-Like Antenna (ILA) and this has been indispensable for operating at low (real) T-point impedance values to investigate ELM tolerance. This paper describes the necessity of

M. Vrancken; E. Lerche; T. Blackman; P. Dumortier; F. Durodié; M. Evrard; R. H. Goulding; M. Graham; S. Huygen; P. Jacquet; A. Kaye; M.-L. Mayoral; M. P. S. Nightingale; J. Ongena; D. van Eester; M. van Schoor; M. Vervier; R. Weynants; JET-EFDA contributors

2009-01-01

74

On the calculation of matrix elements of one body operators in many nucleon systems  

Microsoft Academic Search

We demonstrate the connection between matrix elements of one body operators in odd nuclei and vertex functions. The procedure is free of assumptions on the pole distribution of the two point functions and it does not use perturbation theory. The renormalization of the external field, necessistated by configuration space limitations, is carried through for scalar, local fields, acting on the

Ernst Werner; Kurt Emrich

1970-01-01

75

Nondestructive Damage Evaluation in Ceramic Matrix Composites for Aerospace Applications  

PubMed Central

Infrared thermography (IRT) and acoustic emission (AE) are the two major nondestructive methodologies for evaluating damage in ceramic matrix composites (CMCs) for aerospace applications. The two techniques are applied herein to assess and monitor damage formation and evolution in a SiC-fiber reinforced CMC loaded under cyclic and fatigue loading. The paper explains how IRT and AE can be used for the assessment of the material's performance under fatigue. IRT and AE parameters are specifically used for the characterization of the complex damage mechanisms that occur during CMC fracture, and they enable the identification of the micromechanical processes that control material failure, mainly crack formation and propagation. Additionally, these nondestructive parameters help in early prediction of the residual life of the material and in establishing the fatigue limit of materials rapidly and accurately.

Dassios, Konstantinos G.; Kordatos, Evangelos Z.; Aggelis, Dimitrios G.; Matikas, Theodore E.

2013-01-01

76

Symmetric nonnegative matrix factorization: algorithms and applications to probabilistic clustering.  

PubMed

Nonnegative matrix factorization (NMF) is an unsupervised learning method useful in various applications including image processing and semantic analysis of documents. This paper focuses on symmetric NMF (SNMF), which is a special case of NMF decomposition. Three parallel multiplicative update algorithms using level 3 basic linear algebra subprograms directly are developed for this problem. First, by minimizing the Euclidean distance, a multiplicative update algorithm is proposed, and its convergence under mild conditions is proved. Based on it, we further propose another two fast parallel methods: ?-SNMF and ? -SNMF algorithms. All of them are easy to implement. These algorithms are applied to probabilistic clustering. We demonstrate their effectiveness for facial image clustering, document categorization, and pattern clustering in gene expression. PMID:22042156

He, Zhaoshui; Xie, Shengli; Zdunek, Rafal; Zhou, Guoxu; Cichocki, Andrzej

2011-12-01

77

Matrix Assisted Ionization in Vacuum, a Sensitive and Widely Applicable Ionization Method for Mass Spectrometry  

NASA Astrophysics Data System (ADS)

An astonishingly simple new method to produce gas-phase ions of small molecules as well as proteins from the solid state under cold vacuum conditions is described. This matrix assisted ionization vacuum (MAIV) mass spectrometry (MS) method produces multiply charged ions similar to those that typify electrospray ionization (ESI) and uses sample preparation methods that are nearly identical to matrix-assisted laser desorption/ionization (MALDI). Unlike these established methods, MAIV does not require a laser or voltage for ionization, and unlike the recently introduced matrix assisted ionization inlet method, does not require added heat. MAIV-MS requires only introduction of a crystalline mixture of the analyte incorporated with a suitable small molecule matrix compound such as 3-nitrobenzonitrile directly to the vacuum of the mass spectrometer. Vacuum intermediate pressure MALDI sources and modified ESI sources successfully produce ions for analysis by MS with this method. As in ESI-MS, ion formation is continuous and, without a laser, little chemical background is observed. MAIV, operating from a surface offers the possibility of significantly improved sensitivity relative to atmospheric pressure ionization because ions are produced in the vacuum region of the mass spectrometer eliminating losses associated with ion transfer from atmospheric pressure to vacuum. Mechanistic aspects and potential applications for this new ionization method are discussed.

Trimpin, Sarah; Inutan, Ellen D.

2013-05-01

78

In situ bioelectrokinetic remediation of phenol-contaminated soil by use of an electrode matrix and a rotational operation mode.  

PubMed

In situ bioremediation is a safe and cost-effective technology for the cleanup of contaminated sites, but its remediation rate is usually very slow. This study attempted to accelerate the process of bioremediation by employing non-uniform electrokinetic transport processes to mix organic pollutants and degrading bacteria in soils under in situ conditions (namely, in situ bioelectrokinetic remediation) by use of an electrode matrix and a rotational operation mode. A bench-scale non-uniform electrokinetic system with periodic polarity-reversal was developed for this purpose, and tested by using a sandy loam spiked with phenol as a model organic pollutant. The results demonstrated that non-uniform electrokinetic processes could enhance the in situ biodegradation of phenol in the soil, the efficiency of which depended upon the operational mode of the electric field. Compared with the unidirectional operation and the bidirectional operation, the rotational operation could effectively stimulate the biodegradation of phenol in the soil if adopting appropriate time intervals of polarity-reversal and electrode matrixes. A reversal interval of 3.0 h and a square-shaped electrode matrix with four electrode couples appeared appropriate for the in situ biodegradation of phenol, at which a maximum phenol removal of 58% was achieved in 10d and the bioremediation rate was increased about five times as compared to that with no electric field applied. The results also showed that adopting a small polarity-reversal interval and an appropriate electrode array could produce a high and uniform removal of phenol from the soil. It is believed that in situ bioelectrokinetic remediation holds the potential for field application. PMID:16406052

Luo, Qishi; Wang, Hui; Zhang, Xihui; Fan, Xiangyu; Qian, Yi

2006-06-01

79

Theory and application of covariance matrix tapers for robust adaptive beamforming  

Microsoft Academic Search

We unify several seemingly disparate approaches to robust adaptive beamforming through the introduction of the concept of a “covariance matrix taper (CMT)”. This is accomplished by recognizing that an important class of adapted pattern modification techniques are realized by the application of a conformal matrix “taper” to the original sample covariance matrix. From the Schur product theorem for positive (semi)

Joseph R. Guerci

1999-01-01

80

On the fine spectrum of the operator defined by a lambda matrix over the sequence space c0 and c  

NASA Astrophysics Data System (ADS)

The main purpose of this paper is to determine the fine spectrum with respect to Goldberg's classification of the operator defined by a lambda matrix over the sequence spaces c0 and c. As a new development, we give the approximate point spectrum, defect spectrum and compression spectrum of the matrix operator Lambda on the sequence spaces c0 and c.

Ye?ilkayagil, Medine; Ba?ar, Feyzi

2012-08-01

81

Solution of Lane-Emden type equations using Bernstein operational matrix of differentiation  

NASA Astrophysics Data System (ADS)

The purpose of this paper is to propose an efficient numerical method for solving Lane-Emden type equations arising in astrophysics using Bernstein polynomials. First Bernstein operational matrix of differentiation is derived using Bernstein polynomials and then applied to solve the linear and nonlinear differential equations of Lane-Emden type. Some illustrative examples are given to demonstrate the efficiency and validity of the proposed algorithm.

Pandey, Rajesh K.; Kumar, Narayan

2012-04-01

82

Operational Experience with the Scattering Matrix Arc Detection System on the JET ITER-Like Antenna  

SciTech Connect

The Scattering Matrix Arc Detection System (SMAD) has been fully deployed on all 4 sets of Resonant Double Loop (RDL), Vacuum Transmission Line (VTL) and Antenna Pressurised Transmission Lines (APTL) of the JET ICRF ITER-Like Antenna (ILA) and this has been indispensable for operating at low (real) T-point impedance values to investigate ELM tolerance. This paper describes the necessity of the SMAD vs VSWR (Voltage Standing Wave Ratio) protection system, SMAD commissioning, problems and a number of typical events detected by the SMAD system during operation on plasma.

Vrancken, M.; Lerche, E.; Dumortier, P.; Durodie, F.; Evrard, M.; Huygen, S.; Ongena, J.; Van Eester, D.; Van Schoor, M.; Vervier, M.; Weynants, R. [LPP/ERM-KMS, Association EURATOM-Belgian State, Brussels (Belgium); Blackman, T.; Graham, M.; Jacquet, P.; Kaye, A.; Mayoral, M.-L.; Nightingale, M. P. S. [EURATOM/UKAEA Fusion Association, Culham Science Center (United Kingdom); Goulding, R. H. [Oak Ridge National Laboratory, Oak Ridge (United States)

2009-11-26

83

Theoretical uncertainties in the nuclear matrix elements of neutrinoless double beta decay: The transition operator  

NASA Astrophysics Data System (ADS)

We explore the theoretical uncertainties related to the transition operator of neutrinoless double-beta (0???) decay. The transition operator used in standard calculations is a product of one-body currents, that can be obtained phenomenologically as in Tomoda [1] or Šimkovic et al. [2]. However, corrections to the operator are hard to obtain in the phenomenological approach. Instead, we calculate the 0??? decay operator in the framework of chiral effective theory (EFT), which gives a systematic order-by-order expansion of the transition currents. At leading orders in chiral EFT we reproduce the standard one-body currents of Refs. [1] and [2]. Corrections appear as two-body (2b) currents predicted by chiral EFT. We compute the effects of the leading 2b currents to the nuclear matrix elements of 0??? decay for several transition candidates. The 2b current contributions are related to the quenching of Gamow-Teller transitions found in nuclear structure calculations.

Menéndez, Javier

2013-12-01

84

Fuzzy geometry via the spinor bundle, with applications to holographic space-time and matrix theory  

SciTech Connect

We present a new framework for defining fuzzy approximations to geometry in terms of a cutoff on the spectrum of the Dirac operator, and a generalization of it that we call the Dirac-flux operator. This framework does not require a symplectic form on the manifold, and is completely rotation invariant on an arbitrary n-sphere. The framework is motivated by the formalism of holographic space-time, whose fundamental variables are sections of the spinor bundle over a compact Euclidean manifold. The strong holographic principle requires the space of these sections to be finite dimensional. We discuss applications of fuzzy spinor geometry to holographic space-time and to matrix theory.

Banks, Tom [NHETC and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019 (United States); SCIPP and Department of Physics, University of California, Santa Cruz, California 95064-1077 (United States); Kehayias, John [SCIPP and Department of Physics, University of California, Santa Cruz, California 95064-1077 (United States)

2011-10-15

85

Random matrix theory for the Hermitian Wilson Dirac operator and the chGUE-GUE transition  

NASA Astrophysics Data System (ADS)

We introduce a random two-matrix model interpolating between a chiral Hermitian (2 n + ?) × (2 n + ?) matrix and a second Hermitian matrix without symmetries. These are taken from the chiral Gaussian Unitary Ensemble (chGUE) and Gaussian Unitary Ensemble (GUE), respectively. In the microscopic large- n limit in the vicinity of the chGUE (which we denote by weakly non-chiral limit) this theory is in one to one correspondence to the partition function of Wilson chiral perturbation theory in the epsilon regime, such as the related two matrix-model previously introduced in [32, 33]. For a generic number of flavours and rectangular block matrices in the chGUE part we derive an eigenvalue representation for the partition function displaying a Pfaffian structure. In the quenched case with ? = 0 , 1 we derive all spectral correlations functions in our model for finite- n, given in terms of skew-orthogonal polynomials. The latter are expressed as Gaussian integrals over standard Laguerre polynomials. In the weakly non-chiral microscopic limit this yields all corresponding quenched eigenvalue correlation functions of the Hermitian Wilson operator.

Akemann, Gernot; Nagao, Taro

2011-10-01

86

Application of the J-matrix method to multichannel scattering  

NASA Astrophysics Data System (ADS)

In this contribution we describe the multichannel extension to the nonrelativistic J-matrix method, and present differential cross sections for scattering of slow electrons from Argon atoms. Nonrelativistic phase shifts, then the S-matrix and the cross sections have been calculated using newly developed Fortran code, JMATRIX-MULTI. We applied the model Hartree-Fock potential as the scattering potential, which was truncated in the oscillatory basis functions.

Syty, P.; Redynk, ?.; Sienkiewicz, J. E.

2013-10-01

87

Structural and functional polymer-matrix composites for electromagnetic applications  

NASA Astrophysics Data System (ADS)

This dissertation addresses the science and technology of functional and structural polymer-matrix composite materials for electromagnetic applications, which include electromagnetic interference (EMI) shielding and low observability (Stealth). The structural composites are continuous carbon fiber epoxy-matrix composites, which are widely used for airframes. The functional composites are composites with discontinuous fillers and in both bulk and coating forms. Through composite structure variation, attractive electromagnetic properties have been achieved. With no degradation of the tensile strength or modulus, the shielding effectiveness of the structural composites has been improved by enhancing multiple reflections through light activation of the carbon fiber. The multiple reflections loss of the electromagnetic wave increases from 1.1 to 10.2 dB at 1.0 GHz due to the activation. Such a large effect of multiple reflections has not been previously reported in any material. The observability of these composites has been lowered by decreasing the electrical conductivity (and hence decreasing the reflection loss) through carbon fiber coating. The incorporation of mumetal, a magnetic alloy particulate filler (28-40 mum size), in a latex paint has been found to be effective for enhancing the shielding only if the electrical resistivity of the resulting composite coating is below 10 O.cm, as rendered by a conductive particulate filler, such as nickel flake (14-20 mum size). This effectiveness (39 dB at 1.0 GHz) is attributed to the absorption of the electromagnetic wave by the mumetal and the nickel flake, with the high conductivity rendered by the presence of the nickel flake resulting in a relatively high reflection loss of 15.5 dB. Without the nickel flake, the mumetal gives only 3 dB of shielding and 1.5 dB of reflection loss at 1.0 GHz. Nickel powder (0.3-0.5 mum size) has been found to be an effective filler for improving the shielding of polyethersulfone (PES) bulk composites. At 13 vol.%, it gives 90 dB of shielding at 1.0 GHz, compared to 46 dB for nickel powder (20-40 mum) and the prior value of 87 dB reported by Shui and Chung for nickel filament (0.4 mum diameter). The minimum filler content for high shielding is 7-13 vol.% for both nickel powders, compared to 3-7 vol.% for nickel filament. Due to the skin effect, a small filler unit size helps the shielding, which is dominated by reflection. Carbon filament (0.1 mum, >100 mum long, >1000 in aspect ratio) is effective for enhancing the shielding effectiveness of a coating made from a water-based colloid that contains graphite particle (0.7-0.8 mum, 22 wt.%) and a starch-type binder. The filament addition increases the shielding from 11 to 20 dB at 1.0 GHz. This increase in shielding is associated with increase in reflectivity and decrease in electrical resistivity. Graphite flake (5 mum) at the same volume proportion is even more effective; its addition increases the shielding from 11 to 28 dB. The combined use of the graphite flake and a low proportion of stainless steel fiber (11 mum diameter, 2 mm long, 180 in aspect ratio) is yet more effective; it increases the shielding from 11 to 34 dB. Alumina particle (5 mum size, 15 vol.%) is effective for increasing the impedance of a coating made from the graphite colloid by 290%, though the shielding effectiveness is reduced from 18 to 11 dB at 1.0 GHz. The high impedance is attractive for MRIcompatible pacemaker leads. The interface between filler and matrix also affects the shielding. Silane treatment of the surface of graphite flake (5 mum) used in the graphite colloid decreases the viscosity (e.g., from 1750 to 1460 CP), but it also decreases the shielding effectiveness (e.g., from 20 to 16 dB at 1 GHz). Ozone treatment gives a similar effect. The decrease of the shielding effectiveness is attributed to the increase in resistivity due to the surface treatment. Measured and calculated values of the reflection loss are comparable, with the measured value lower than the corresponding calculated value, when th

Wu, Junhua

88

Real time evolution at finite temperatures with operator space matrix product states  

NASA Astrophysics Data System (ADS)

We propose a method to simulate the real time evolution of one-dimensional quantum many-body systems at finite temperature by expressing both the density matrices and the observables as matrix product states. This allows the calculation of expectation values and correlation functions as scalar products in operator space. The simulations of density matrices in inverse temperature and the local operators in the Heisenberg picture are independent and result in a grid of expectation values for all intermediate temperatures and times. Simulations can be performed using real arithmetics with only polynomial growth of computational resources in inverse temperature and time for integrable systems. The method is illustrated for the XXZ model and the single impurity Anderson model.

Pižorn, Iztok; Eisler, Viktor; Andergassen, Sabine; Troyer, Matthias

2014-07-01

89

Evaluating wilderness recreational opportunities: Application of an impact matrix  

Microsoft Academic Search

An inventory of the severity and spatial distribution of wilderness campsite impacts in Sequoia and Kings Canyon National Parks identified a total of 273 distinct nodes of campsites or ``management areas.'' A campsite impact matrix was developed to evaluate management areas based on total impacts (correlated to the total area of campsite development) and the density, or concentration, of impacts

Thomas J. Stohlgren; David J. Parsons

1992-01-01

90

hiTRAN® Wire Matrix Inserts in Fouling Applications  

Microsoft Academic Search

Fouling characteristics are dictated largely by the properties of the thermal and hydrodynamic boundary layers. As a result, fouling mitigation strategies must take into account the conditions in this region. hiTRAN wire matrix tube inserts are a useful tool in altering the conditions near the tube wall, especially in the laminar and transition flow regions. This review article considers particle

J. M. Ritchie; P. Droegemueller; M. J. H. Simmons

2009-01-01

91

Finite-Temperature Matrix Product State Algorithms and Applications  

NASA Astrophysics Data System (ADS)

We review the basic theory of matrix product states (MPS) as a numerical variational ansatz for time evolution, and present two methods to simulate finite temperature systems with MPS: the ancilla method and the minimally entangled typical thermal state method. A sample calculation with the Bose-Hubbard model is provided.

Wall, Michael L.; Carr, Lincoln D.

2013-02-01

92

Development of Ceramic Matrix Composites For High Temperature Applications  

NASA Technical Reports Server (NTRS)

The microstructure and mechanical properties of carbon fiber reinforced silicon carbide (C/SiC) composites that incorporated molecular-level oxidation inhibitors designed to increase the material s high temperature durability were characterized. The viability of a fiber-level inhibitor incorporated as part of a layered interface system as well as a molecularly-integrated matrix-level oxidation inhibitor that is co-deposited with the SiC matrix during Chemical Vapor Infiltration (CVI) was determined. It was expected that the inhibitor would act as a glass former that will getter the oxygen and form a crack sealant to reduce further ingress of oxygen into the composite. Three composites were examined. Composite A was a baseline C(sub f)/SiC(sub m) composite that incorporated a approx. 0.4 micron pyrolytic carbon (PyC) fiber coating to promote strength and toughness, and a CVI-derived SiC matrix. Composite B was a C(sub f)/SiC(sub m) composite incorporating a approx 0.4 micron pyrolytic carbon (PyC) fiber coating to promote strength and toughness, a approx. 0.6 micron B4C fiber-level oxidation barrier coating, and a CVI-derived SiC matrix. Composite C was a C(sub f) /SiC(sub m) composite that incorporated a approx. 0.4 micron pyrolytic carbon (PyC) fiber coating to promote strength and toughness, a approx. 0.6 micron B4C fiber-level oxidation barrier coating, and a BxC-SiC oxidation-inhibited matrix produced by CVI co-deposition. All composites were reinforced with 10 plies of T-300 balanced plain weave carbon fabric with 3K tows at 12.5 ends per inch.

Heimann, Paula

2004-01-01

93

Calculating massive 3-loop graphs for operator matrix elements by the method of hyperlogarithms  

NASA Astrophysics Data System (ADS)

We calculate convergent 3-loop Feynman diagrams containing a single massive loop equipped with twist ?=2 local operator insertions corresponding to spin N. They contribute to the massive operator matrix elements in QCD describing the massive Wilson coefficients for deep-inelastic scattering at large virtualities. Diagrams of this kind can be computed using an extended version of the method of hyperlogarithms, originally being designed for massless Feynman diagrams without operators. The method is applied to Benz- and V-type graphs, belonging to the genuine 3-loop topologies. In case of the V-type graphs with five massive propagators, new types of nested sums and iterated integrals emerge. The sums are given in terms of finite binomially and inverse binomially weighted generalized cyclotomic sums, while the 1-dimensionally iterated integrals are based on a set of ?30 square-root valued letters. We also derive the asymptotic representations of the nested sums and present the solution for N?C. Integrals with a power-like divergence in N-space ?aN,a?R,a>1, for large values of N emerge. They still possess a representation in x-space, which is given in terms of root-valued iterated integrals in the present case. The method of hyperlogarithms is also used to calculate higher moments for crossed box graphs with different operator insertions.

Ablinger, Jakob; Blümlein, Johannes; Raab, Clemens; Schneider, Carsten; Wißbrock, Fabian

2014-08-01

94

Evaluating wilderness recreational opportunities: Application of an impact matrix  

NASA Astrophysics Data System (ADS)

An inventory of the severity and spatial distribution of wilderness campsite impacts in Sequoia and Kings Canyon National Parks identified a total of 273 distinct nodes of campsites or “management areas.” A campsite impact matrix was developed to evaluate management areas based on total impacts (correlated to the total area of campsite development) and the density, or concentration, of impacts relative to each area's potentially campable area. The matrix is used to quantify potential recreational opportunities for wilderness visitors in a spectrum from areas offering low impact-dispersed camping to those areas offering high impact-concentrated camping. Wilderness managers can use this type of information to evaluate use distribution patterns, identify areas to increase or decrease use, and to identify areas needing site-specific regulations (e.g., one-night camping limits) to preserve wilderness resources and guarantee outstanding opportunities for solitude.

Stohlgren, Thomas J.; Parsons, David J.

1992-05-01

95

Evaluating wilderness recreational opportunities: Application of an impact matrix  

Microsoft Academic Search

An inventory of the severity and spatial distribution of wilderness campsite impacts in Sequoia and Kings Canyon National\\u000a Parks identified a total of 273 distinct nodes of campsites or “management areas.” A campsite impact matrix was developed\\u000a to evaluate management areas based on total impacts (correlated to the total area of campsite development) and the density,\\u000a or concentration, of impacts

Thomas J. Stohlgren; David J. Parsons

1992-01-01

96

Highly efficient and low-operating-voltage OLEDs for active and passive matrix displays  

NASA Astrophysics Data System (ADS)

The operating voltage of organic light emitting diodes (OLEDs) is important for the power consumption of active or passive matrix displays since it influences both the power consumption of the OLED itself and the power consumption of the driver circuitry. We have shown that very low operating voltages can be achieved in small-molecule OLED by intentional electrical n- and p-type doping. Even more important than the reduction of the voltage is the fact that doping of the charge carrier transport layers improves charge injection, making it basically independent on the actual contact work-functions. Organic light emitting diodes (OLEDs) with electrically doped transport layers show significantly improved properties: For instance, we have achieved a brightness of 100cd/m2 already at a voltage of 2.55V (based on a simple singlet emitter system), well below previous results for undoped small-molecule devices. With phosphorescent emitter dopants, high quantum and power efficiency of OLEDs with doped transport layers can be achieved: operating voltages and current efficiencies of 3.1V and 44cd/A (corresponding to approx. 44lm/Watt at 100cd/m2) are reported here. Inverted and fully transparent devices with parameters comparable to standard bottom-emitting OLED have been demonstrated as well.

Blochwitz-Nimoth, Jan; Pfeiffer, Martin; Zhou, Xiang; Huang, Jingsong; He, Gufeng; Leo, Karl

2004-02-01

97

Massive 3-loop ladder diagrams for quarkonic local operator matrix elements  

NASA Astrophysics Data System (ADS)

3-loop diagrams of the ladder-type, which emerge for local quarkonic twist-2 operator matrix elements, are computed directly for general values of the Mellin variable N using Appell-function representations and applying modern summation technologies provided by the package Sigma and the method of hyperlogarithms. In some of the diagrams generalized harmonic sums with ??{1,1/2,2} emerge beyond the usual nested harmonic sums. As the asymptotic representation of the corresponding integrals shows, the generalized sums conspire giving well behaved expressions for large values of N. These diagrams contribute to the 3-loop heavy flavor Wilson coefficients of the structure functions in deep-inelastic scattering in the region Q2?m2.

Ablinger, Jakob; Blümlein, Johannes; Hasselhuhn, Alexander; Klein, Sebastian; Schneider, Carsten; Wißbrock, Fabian

2012-11-01

98

Magnet operating experience review for fusion applications  

SciTech Connect

This report presents a review of magnet operating experiences for normal-conducting and superconducting magnets from fusion, particle accelerator, medical technology, and magnetohydrodynamics research areas. Safety relevant magnet operating experiences are presented to provide feedback on field performance of existing designs and to point out the operational safety concerns. Quantitative estimates of magnet component failure rates and accident event frequencies are also presented, based on field experience and on performance of similar components in other industries.

Cadwallader, L.C.

1991-11-01

99

Space Operations Learning Center Facebook Application  

NASA Technical Reports Server (NTRS)

The proposed Space Operations Learning Center (SOLC) Facebook module, initially code-named Spaceville, is intended to be an educational online game utilizing the latest social networking technology to reach a broad audience base and inspire young audiences to be interested in math, science, and engineering. Spaceville will be a Facebook application/ game with the goal of combining learning with a fun game and social environment. The mission of the game is to build a scientific outpost on the Moon or Mars and expand the colony. Game activities include collecting resources, trading resources, completing simple science experiments, and building architectures such as laboratories, habitats, greenhouses, machine shops, etc. The player is awarded with points and achievement levels. The player s ability increases as his/her points and levels increase. A player can interact with other players using multiplayer Facebook functionality. As a result, a player can discover unexpected treasures through scientific missions, engineering, and working with others. The player creates his/her own avatar with his/her selection of its unique appearance, and names the character. The player controls the avatar to perform activities such as collecting oxygen molecules or building a habitat. From observations of other successful social online games such as Farmville and Restaurant City, a common element of these games is having eye-catching and cartoonish characters, and interesting animations for all activities. This will create a fun, educational, and rewarding environment. The player needs to accumulate points in order to be awarded special items needed for advancing to higher levels. Trophies will be awarded to the player when certain goals are reached or tasks are completed. In order to acquire some special items needed for advancement in the game, the player will need to visit his/her neighboring towns to discover the items. This is the social aspect of the game that requires the player to go out of his/her own establishment to explore what is in the neighborhood. Spaceville will take advantage of Facebook s successful architecture to inspire a new audience of scientists and engineers for the future.

Lui, Ben; Milner, Barbara; Binebrink, Dan; Kuok, Heng

2012-01-01

100

Wave operator bounds for one-dimensional Schroedinger operators with singular potentials and applications  

SciTech Connect

Boundedness of wave operators for Schroedinger operators in one space dimension for a class of singular potentials, admitting finitely many Dirac delta distributions, is proved. Applications are presented to, for example, dispersive estimates and commutator bounds.

Duchene, Vincent [Equipe EDP, DMA - Ecole Normale Superieure, 45, rue d'Ulm, 75230 Paris Cedex 05 (France); Marzuola, Jeremy L. [Department of Mathematics, University of North Carolina-Chapel Hill, Phillips Hall, Chapel Hill, North Carolina 27599 (United States); Weinstein, Michael I. [Department of Applied Physics and Applied Mathematics, Columbia University, 200 S. W. Mudd, 500 W. 120th St., New York City, New York 10027 (United States)

2011-01-15

101

The synthesis, compressive properties, and applications of metal matrix syntactic foams  

NASA Astrophysics Data System (ADS)

Metal matrix syntactic foams are composites that incorporate hollow particles in a matrix, where enclosing porosity inside the thin shell of the particle leads to low density without large decreases in mechanical properties. Studies on Al, Mg, Pb, and Zn alloy matrix syntactic foams are available in the published literature. A large stress plateau region appears in the compressive stress-strain graphs of metal matrix syntactic foams. The height and length of stress plateau can be tailored by means of particle wall thickness, volume fraction, and size, and the total compressive energy absorption can be controlled. Metal matrix syntactic foams seem promising in various energy absorbing applications including automobile parts since their energy absorption capability per unit weight is better than other foams and lightweight materials.

Rohatgi, Pradeep K.; Gupta, Nikhil; Schultz, Benjamin F.; Luong, Dung D.

2011-02-01

102

A two scale model of porous rocks with Drucker–Prager matrix: Application to a sandstone  

Microsoft Academic Search

The present paper is devoted to a micromechanical model of porous rocks and its application to a sandstone. This original model takes advantage of a recent homogenization-based macroscopic yield function which couples Drucker–Prager type plasticity of the solid matrix and evolving porosity. Its formulation and implementation are described. Application to a Vosges sandstone shows that, except for very low confining

J. Lin; J.-F. Shao; D. Kondo

2011-01-01

103

Improved maldi-tof microbial mass spectrometry imaging by application of a dispersed solid matrix.  

PubMed

The key step in high quality microbial matrix-assisted laser desorption/ionization mass spectrometry imaging (microbial MALDI MSI) is the fabrication of a homogeneous matrix coating showing a fine-grained morphology. This application note addresses a novel method to apply solid MALDI matrices onto microbial cultures grown on thin agar media. A suspension of a mixture of 2,5-DHB and ?-CHCA is sprayed onto the agar sample surface to form highly homogeneous matrix coatings. As a result, the signal intensities of metabolites secreted by the fungus Aspergillus fumigatus were found to be clearly enhanced. PMID:24894842

Vergeiner, Stefan; Schafferer, Lukas; Haas, Hubertus; Müller, Thomas

2014-08-01

104

Improved MALDI-TOF Microbial Mass Spectrometry Imaging by Application of a Dispersed Solid Matrix  

NASA Astrophysics Data System (ADS)

The key step in high quality microbial matrix-assisted laser desorption/ionization mass spectrometry imaging (microbial MALDI MSI) is the fabrication of a homogeneous matrix coating showing a fine-grained morphology. This application note addresses a novel method to apply solid MALDI matrices onto microbial cultures grown on thin agar media. A suspension of a mixture of 2,5-DHB and ?-CHCA is sprayed onto the agar sample surface to form highly homogeneous matrix coatings. As a result, the signal intensities of metabolites secreted by the fungus Aspergillus fumigatus were found to be clearly enhanced.

Vergeiner, Stefan; Schafferer, Lukas; Haas, Hubertus; Müller, Thomas

2014-06-01

105

PCOS - An operating system for modular applications  

NASA Technical Reports Server (NTRS)

This paper is an introduction to the PCOS operating system for the MC68000 family processors. Topics covered are: development history; development support; rational for development of PCOS and salient characteristics; architecture; and a brief comparison of PCOS to UNIX.

Tharp, V. P.

1986-01-01

106

Application of Nonnegative Matrix Factorization to Musical Instrument Classification  

Microsoft Academic Search

In this paper, a class of algorithms for automatic classification of individual musical instrument sounds is pre- sented. Several perceptual features used in general sound clas- sification applications were measured for 300 sound recordings consisting of 6 different musical instrument classes (piano, vio- lin, cello, flute, bassoon, and soprano saxophone). In addition, MPEG-7 basic spectral and spectral basis descriptors were

Emmanouil Benetos; Margarita Kotti; Constantine Kotropoulos

107

Reduced density matrix hybrid approach: Application to electronic energy transfer  

NASA Astrophysics Data System (ADS)

Electronic energy transfer in the condensed phase, such as that occurring in photosynthetic complexes, frequently occurs in regimes where the energy scales of the system and environment are similar. This situation provides a challenge to theoretical investigation since most approaches are accurate only when a certain energetic parameter is small compared to others in the problem. Here we show that in these difficult regimes, the Ehrenfest approach provides a good starting point for a dynamical description of the energy transfer process due to its ability to accurately treat coupling to slow environmental modes. To further improve on the accuracy of the Ehrenfest approach, we use our reduced density matrix hybrid framework to treat the faster environmental modes quantum mechanically, at the level of a perturbative master equation. This combined approach is shown to provide an efficient and quantitative description of electronic energy transfer in a model dimer and the Fenna-Matthews-Olson complex and is used to investigate the effect of environmental preparation on the resulting dynamics.

Berkelbach, Timothy C.; Markland, Thomas E.; Reichman, David R.

2012-02-01

108

Operational Applications of Satellite Snowcover Observations  

NASA Technical Reports Server (NTRS)

The history of remote sensing of snow cover is reviewed and the following topics are covered: various techniques for interpreting LANDSAT and NOAA satellite data; the status of future systems for continuing snow hydrology applications; the use of snow cover observations in streamflow forecasts by Applications Systems Verification and Transfer participants and selected foreign investigators; and the benefits of using satellite snow cover data in runoff prediction.

Rango, A. (editor); Peterson, R. (editor)

1980-01-01

109

Matrix elements of the electromagnetic operator between kaon and pion states  

SciTech Connect

We compute the matrix elements of the electromagnetic operator sF{sub {mu}{nu}}{sigma}{sup {mu}{nu}}d between kaon and pion states, using lattice QCD with maximally twisted-mass fermions and two flavors of dynamical quarks (N{sub f}=2). The operator is renormalized nonperturbatively in the RI'/MOM scheme and our simulations cover pion masses as light as 270 MeV and three values of the lattice spacing from {approx_equal}0.07 up to {approx_equal}0.1 fm. At the physical point our result for the corresponding tensor form factor at zero-momentum transfer is f{sub T}{sup K{pi}}(0)=0.417(14{sub stat})(5{sub syst}), where the systematic error does not include the effect of quenching the strange and charm quarks. Our result differs significantly from the old quenched result f{sub T}{sup K{pi}}(0)=0.78(6) obtained by the SPQ{sub cd}R Collaboration with pion masses above 500 MeV. We investigate the source of this difference and conclude that it is mainly related to the chiral extrapolation. We also study the tensor charge of the pion and obtain the value f{sub T}{sup {pi}{pi}}(0)=0.195(8{sub stat})(6{sub syst}) in good agreement with, but more accurate than the result f{sub T}{sup {pi}{pi}}(0)=0.216(34) obtained by the QCDSF Collaboration using higher pion masses.

Baum, I. [Dip. di Fisica, Universita di Roma ''La Sapienza'', P.le A. Moro 5, I-00185 Roma (Italy); Lubicz, V. [Dip. di Fisica, Universita Roma Tre, Via della Vasca Navale 84, I-00146 Roma (Italy); INFN, Sezione di Roma Tre, Via della Vasca Navale 84, I-00146 Roma (Italy); Martinelli, G. [SISSA, Via Bonomea 265, I-34136 Trieste (Italy); Orifici, L. [Dip. di Fisica, Universita Roma Tre, Via della Vasca Navale 84, I-00146 Roma (Italy); Simula, S. [INFN, Sezione di Roma Tre, Via della Vasca Navale 84, I-00146 Roma (Italy)

2011-10-01

110

Operators of fractional integration and their applications  

Microsoft Academic Search

The main purpose of this paper is to present a systematic (and historical) account of the investigations carried out by various authors in the field of fractional calculus and its applications. Several interesting results, relevant to the present investigation, are also considered.

H. M. Srivastava; R. K. Saxena

2001-01-01

111

Biosignal operating system for telemedical applications  

NASA Astrophysics Data System (ADS)

This paper describes the principles and prototype architecture of a biosignal operating system for monitoring, diagnosing and treating diseases online. The distinguishing feature of the system is its ability to interface with the human body in a medically relevant manner. Three units in the system ensure machine-body interoperability. First is a biosignal acquisition and processing unit. The second unit draws conclusions from the acquired information while the third enables non-invasive therapies. The entire operation aims at locating the biological resources available for treatment and gaining access to them at run-time. This eliminates the need for medical records. In addition, a protocol for uniform disease definition eliminates the need for massive databasing and frequent updating. The drawback is that the system requires investigations into the biological resources of communication -- a gray area even in molecular biology. Preliminary tests, however, indicate that our technology supports online delivery of comprehensive medical services over the Internet.

Leca, Radu; Osvath, Laszlo; Kettle, Eva

1999-07-01

112

Operational solar irradiances for satellite drag applications  

Microsoft Academic Search

We report on major improvements to operational solar energy inputs for use in Jacchia-type empirical thermospheric density models to significantly improve Low Earth Orbit (LEO) satellite drag estimation. Three solar indices, compared to only one in the original Jacchia-type and MSIS-type models, best represent the complex interaction between a) the solar emission source (photosphere, chromosphere, corona), b) the irradiances' penetration

S. Bouwer; W. Tobiska

2006-01-01

113

LOCSET Phase Locking: Operation, Diagnostics, and Applications  

NASA Astrophysics Data System (ADS)

The aim of this dissertation is to discuss the theoretical and experimental work recently done with the Locking of Optical Coherence via Single-detector Electronic-frequency Tagging (LOCSET) phase locking technique developed and employed here are AFRL. The primary objectives of this effort are to detail the fundamental operation of the LOCSET phase locking technique, recognize the conditions in which the LOCSET control electronics optimally operate, demonstrate LOCSET phase locking with higher channel counts than ever before, and extend the LOCSET technique to correct for low order, atmospherically induced, phase aberrations introduced to the output of a tiled array of coherently combinable beams. The experimental work performed for this effort resulted in the coherent combination of 32 low power optical beams operating with unprecedented LOCSET phase error performance of lambda/71 RMS in a local loop beam combination configuration. The LOCSET phase locking technique was also successfully extended, for the first time, into an Object In the Loop (OIL) configuration by utilizing light scattered off of a remote object as the optical return signal for the LOCSET phase control electronics. Said LOCSET-OIL technique is capable of correcting for low order phase aberrations caused by atmospheric turbulence disturbances applied across a tiled array output.

Pulford, Benjamin N.

114

Graph theoretical approach to the evaluation of matrix elements of one-body operators in SU(n)  

Microsoft Academic Search

A graph theoretical formulation of SN adapted irreducible representations (irrep) of SU(n) is presented. Closed form expressions involving only SN and SU(n) irrep labels are derived for the matrix elements of one-body operators in the unitary group approach based on the group generators.

R. D. Kent; M. Schlesinger

1986-01-01

115

Application of adjoint operators to neural learning  

NASA Technical Reports Server (NTRS)

A technique for the efficient analytical computation of such parameters of the neural architecture as synaptic weights and neural gain is presented as a single solution of a set of adjoint equations. The learning model discussed concentrates on the adiabatic approximation only. A problem of interest is represented by a system of N coupled equations, and then adjoint operators are introduced. A neural network is formalized as an adaptive dynamical system whose temporal evolution is governed by a set of coupled nonlinear differential equations. An approach based on the minimization of a constrained neuromorphic energylike function is applied, and the complete learning dynamics are obtained as a result of the calculations.

Barhen, J.; Toomarian, N.; Gulati, S.

1990-01-01

116

Robust Joining and Assembly of Ceramic Matrix Composites for High Temperature Applications  

NASA Technical Reports Server (NTRS)

Advanced ceramic matrix composites (CMCs) are under active consideration for use in a wide variety of high temperature applications within the aerospace, energy, and nuclear industries. The engineering designs of CMC components require fabrication and manufacturing of large and complex shaped parts of various thicknesses. In many instances, it is more economical to build up complex shapes by joining simple geometrical shapes. Thus, joining and attachment have been recognized as enabling technologies for successful utilization of ceramic components in various demanding applications. In this presentation, various challenges and opportunities in design, fabrication, and testing of high temperature joints in ceramic matrix composites will be presented. A wide variety of ceramic composites, in different shapes and sizes, have been joined using an affordable, robust ceramic joining technology (ARCJoinT). Microstructure and mechanical properties of joints in melt infiltrated and CVI Sic matrix composites will be reported. Various joint design philosophies and design issues in joining of composites will be discussed.

Singh, Mrityunjay

2003-01-01

117

Application of fuzzy logic operation and control to BWRs  

SciTech Connect

Fuzzy logic control schemes employing linguistic decision rules for flexible operator control strategies have undergone application tests in dynamic systems. The advantages claimed for fuzzy logic control are its abilities: (a) to facilitate direct use of skillful operator know-how for automatic operation and control of the systems and (b) to provide robust multivariable control for complex plants. The authors have also studied applications of fuzzy logic control to automatic startup operations and load-following control in boiling water reactors, pursuing these same advantages.

Junichi Tanji; Mitsuo Kinoshita; Takaharu Fukuzaki; Yasuhiro Kobayashi (Hitachi Ltd., Energy Research Lab., Ibaraki (Japan))

1993-01-01

118

Assessment of Geophysical Techniques Application during CTBTO On-Site inspections using the Evaluation Matrix concept  

Microsoft Academic Search

Application of geophysical methods to collect evidence of possible conduct of an underground nuclear explosion is an essential element of the on-site inspection (OSI) verification component of the Comprehensive Nuclear Test Ban Treaty (CTBT). As with any geophysical survey, effective use of resources during an OSI is essential. The evaluation matrix approach can be applied to both assess in a

Luis R. Gaya-Piqué; Stefka Stefanova; Ward L. Hawkins; Jerry J. Sweeney; Mordechai Melamud; Matjaz Prah

2010-01-01

119

Application of Eshelby's Tensor and Rotation Matrix for the Evaluation of Thermal Transport Properties of Composites  

Microsoft Academic Search

Many applications in the electronic industry require an optimum combination of thermal transport properties (e.g., high thermal conductivity for a given coefficient of thermal expansion). This combination cannot possibly be obtained using a single material and hence requires judicious selection of matrix material with appropriate distribution of the second phase to form a composite. Such a composite provide the combination

Girish Khare; Namas Chandra; Jean-François Silvain

2008-01-01

120

Ceramic matrix composite applications in advanced liquid fuel rocket engine turbomachinery  

NASA Technical Reports Server (NTRS)

Fiber-reinforced ceramic matrix composites have been identified with properties suitable for near term applications. Conceptual design studies indicate the feasibility of applying C/SiC, and subelements were manufactured that verify selected fabrication features and key material properties. Tests and inspection of these subelements confirmed their capabilities.

Brockmeyer, Jerry W.

1992-01-01

121

The generalized transmission matrix for electron-wave-optics through biased heterostructures: Quantum device applications  

Microsoft Academic Search

The transmission matrix approach is generalized to calculate the transmission probability of obliquely incident electrons through arbitrary shape potential profiles. Transmission probability is obtained as a function of the electron energy, the angle of incidence, and the applied voltage across the structure. Applications to electron waveguide and quantum resonant tunneling are outlined. Numerical results are presented for angle dependent resonant

A. M. Kan'an; A. Puri

1994-01-01

122

Applications and comparisons of methods of computing the S Matrix of 2-ports  

SciTech Connect

We report on the application of three different methods of computing the S Matrix for 2-port microwave circuits. The four methods are modal expansions with field matching across boundaries, time domain integration of Maxwell`s equations as implemented in MAFIA, HFSS (high frequency structure simulator), and the KKY frequency domain method. Among the applications to be described are steps in rectangular waveguides and irises in waveguides.

Jones, R.M.; Ko, Kwok; Tantawi, S. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Kroll, N. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)]|[California Univ., San Diego, La Jolla, CA (United States); Yu, D. [Duly Research, Inc., Rancho Palos Verdes, CA (United States)

1993-05-01

123

Imaging MALDI mass spectrometry of sphingolipids using an oscillating capillary nebulizer matrix application system.  

PubMed

Matrix deposition is a critical step in tissue imaging by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). It greatly affects the quality of MALDI imaging, especially for the analytes (such as lipids) that may easily dissolve in the solvent used for the matrix application. This chapter describes the use of an oscillating capillary nebulizer (OCN) to spray small droplets of matrix aerosol onto the sample surface for improved matrix homogeneity, reduced crystal size, and controlled solvent effects. This protocol allows visualization of many different lipid species and, of particular interest, sphingolipids in tissue slices of Tay-Sachs/Sandhoff disease by imaging MALDI-MS. The structures of these lipids were identified by analysis of tissue extracts using electrospray ionization in conjunction with tandem mass spectrometry (MS/MS and MS(3)). These results illustrate the usefulness of tissue imaging MALDI-MS with matrix deposition by OCN for the molecular analysis in normal physiology and pathology. In addition, the observation of numerous lipid subclasses with distinct localizations in the brain slices demonstrates that imaging MALDI-MS could be effectively used for "lipidomic" studies. PMID:20680588

Chen, Yanfeng; Liu, Ying; Allegood, Jeremy; Wang, Elaine; Cachón-González, Begoña; Cox, Timothy M; Merrill, Alfred H; Sullards, M Cameron

2010-01-01

124

Operational solar irradiances for satellite drag applications  

NASA Astrophysics Data System (ADS)

We report on major improvements to operational solar energy inputs for use in Jacchia-type empirical thermospheric density models to significantly improve Low Earth Orbit (LEO) satellite drag estimation. Three solar indices, compared to only one in the original Jacchia-type and MSIS-type models, best represent the complex interaction between a) the solar emission source (photosphere, chromosphere, corona), b) the irradiances' penetration into the thermosphere (unit optical depth in the middle and lower thermosphere), and c) the length of time for energy transfer between thermospheric layers, i.e., the thermal process of molecular conduction or the kinetic process of molecular diffusion. We have found that the existing 10.7-cm radio flux (F10.7) solar proxy plus two new solar indices/proxies substantially improve density modeling. First, the new S10.7 index accounts for 75 percent of the daily density variability with a 1-day lag, is reported in units of F10.7, is the chromospheric EUV energy between 26-34 nm as measured by the SOHO SEM instrument, and is absorbed by atomic oxygen above 200 km. Second, the new M10.7 proxy accounts for 12 percent of the daily density variability with a 5-day lag. It is formed by the Mg II core-to-wing ratio reported in units of F10.7, is used as a substitute for the far ultraviolet (FUV) lower chromosphere/photosphere Schumann-Runge Continuum (SRC) energy that is dominated by the 145-165 nm range and has a unit optical depth in the lower thermosphere, and is the main source of thermospheric molecular oxygen dissociation not historically included in Jacchia- and MSIS-type models. Third, the F10.7 proxy accounts for 13 percent of the daily density variability with a 1-day lag, is the transition region/coronal XUV/EUV energy less than 121 nm and has a unit optical depth throughout the thermosphere, being absorbed by many neutral species. We describe the deployment of the new solar indices in an operational system for use by the space systems community that is concerned with LEO satellite drag.

Bouwer, S.; Tobiska, W.

2006-12-01

125

Applications of graphic correlation in operational activities  

SciTech Connect

When log and seismic correlations are ambiguous or too coarse, graphic correlation is effective in increasing the accuracy of correlations during operational activities. The initial cross-plot of horizons (biostratigraphic and log) from the drill well and a nearby well can be used to estimate depths of horizons not initially recognized or misidentified. The final plot can be used to locate and determine the amount of missing section caused by faults or unconformities. In one example, a plot of 27 biostratigraphic and log picks indicates that two unconformities and a fault in the drill well removed sands found in the control well. If a horizon's depth needs to be accurately predicted (abnormal pressure, casing or coring point), graphic correlation is useful. An example is an attempt to core an interval during its initial penetration, which a control well indicates is overlain by the Calcidiscus macintyrei extinction. At a drilling stoppage the plot is extrapolated, indicating that the C. macintyrei extinction should be found 800 feet below TD. Drilling can then continue at aq normal rate before decreasing near the target's top, saving drill time. The plot can also be used to illustrate whether an objective has been penetrated. In an example, initial log correlations indicate that a well has reached its target, just above the Discoaster quinqueramus extinction. However, no D. quinqueramus specimens are found. Graphic correlation indicates a linear relative sedimentation rate between the drill well and control well, and projects the D. quinqueramus extinction below the TD, persuading management to continue drilling.

Denne, R.A. (Exxon Exploration Co., Houston, TX (United States))

1996-01-01

126

Hypermedia and intelligent tutoring applications in a mission operations environment  

NASA Technical Reports Server (NTRS)

Hypermedia, hypertext and Intelligent Tutoring System (ITS) applications to support all phases of mission operations are investigated. The application of hypermedia and ITS technology to improve system performance and safety in supervisory control is described - with an emphasis on modeling operator's intentions in the form of goals, plans, tasks, and actions. Review of hypermedia and ITS technology is presented as may be applied to the tutoring of command and control languages. Hypertext based ITS is developed to train flight operation teams and System Test and Operation Language (STOL). Specific hypermedia and ITS application areas are highlighted, including: computer aided instruction of flight operation teams (STOL ITS) and control center software development tools (CHIMES and STOL Certification Tool).

Ames, Troy; Baker, Clifford

1990-01-01

127

Azo-derivatives thin films grown by matrix-assisted pulsed laser evaporation for non-linear optical applications  

NASA Astrophysics Data System (ADS)

Azo-dye compounds, in bulk or as thin films, are extensively studied due to their particular optical properties. These properties include non-linear interaction, e.g. two-photon absorption, optical limiting and all-optical poling, with potential applications in optoelectronics and sensors development. Herein, we report on the deposition of pyrazolone derivatives, namely 1-phenyl-3-methyl-4-(1?-azo-2?-sodium carboxylate)-pyrazole-5-one thin films, for applications in second harmonic generation. Matrix-assisted pulsed laser evaporation was employed for layers growth, using a Nd:YAG device operating at 266 nm (4?). The structure and surface morphology of the deposited films were examined by Fourier transform infrared spectroscopy, atomic force microscopy, and scanning electron microscopy. Spectroscopic-ellipsometry was employed to investigate thin film optical properties. Significant second harmonic generation capabilities of the compound were pointed out by using a femtosecond Ti:sapphire laser.

Constantinescu, C.; Matei, A.; Ionita, I.; Ion, V.; Marascu, V.; Dinescu, M.; Vasiliu, C.; Emandi, A.

2014-05-01

128

Boron-bearing species in ceramic matrix composites for long-term aerospace applications  

NASA Astrophysics Data System (ADS)

Boron-bearing refractory species are introduced in non-oxide ceramic matrix fibrous composites (such as SiC/SiC composites) to improve their oxidation resistance under load at high temperatures with a view to applications in the aerospace field. B-doped pyrocarbon and hex-BN have been successfully used as interphase (instead of pure pyrocarbon) either as homogeneous or multilayered fiber coatings, to arrest and deflect matrix cracks formed under load (mechanical fuse function) and to give toughness to the materials. A self-healing multilayered matrix is designed and used in a model composite, which combines B-doped pyrocarbon mechanical fuse layers and B- and Si-bearing compound (namely B 4C and SiC) layers forming B 2O 3-based fluid healing phases when exposed to an oxidizing atmosphere. All the materials are deposited by chemical vapor infiltration. Lifetimes under tensile loading of several hundreds hours at high temperatures are reported.

Naslain, R.; Guette, A.; Rebillat, F.; Pailler, R.; Langlais, F.; Bourrat, X.

2004-02-01

129

Artificial intelligence program in a computer application supporting reactor operations  

SciTech Connect

Improving nuclear reactor power plant operability is an ever-present concern for the nuclear industry. The definition of plant operability involves a complex interaction of the ideas of reliability, safety, and efficiency. This paper presents observations concerning the issues involved and the benefits derived from the implementation of a computer application which combines traditional computer applications with artificial intelligence (AI) methodologies. A system, the Component Configuration Control System (CCCS), is being installed to support nuclear reactor operations at the Experimental Breeder Reactor II.

Stratton, R.C.; Town, G.G.

1985-01-01

130

Operation and Applications of the Boron Cathodic Arc Ion Source  

NASA Astrophysics Data System (ADS)

The boron cathodic arc ion source has been developed with a view to several applications, particularly the problem of shallow junction doping in semiconductors. Research has included not only development and operation of the boron cathode, but other cathode materials as well. Applications have included a large deposition directed toward development of a neutron detector and another deposition for an orthopedic coating, as well as the shallow ion implantation function. Operational experience is described and information pertinent to commercial operation, extracted from these experiments, is presented.

Williams, J. M.; Klepper, C. C.; Chivers, D. J.; Hazelton, R. C.; Freeman, J. H.

2008-11-01

131

Growth conditions, compact perturbations and operator subdecomposability, with applications to generalized Cesàro operators  

NASA Astrophysics Data System (ADS)

We adapt recent results of Albrecht and Ricker to obtain conditions under which growth constraints on the left resolvent of a Banach space operator are preserved under suitable perturbations. As an application, we establish Bishop's property ([beta]) for certain generalized Cesàro operators on the classical Hardy spaces Hp, 1operators.

Miller, T. L.; Miller, V. G.; Neumann, M. M.

2005-01-01

132

Decellularized cartilage matrix as a novel biomatrix for cartilage tissue-engineering applications.  

PubMed

Damage of cartilage structures in the head and neck region as well as in orthopedic sites are frequently caused by trauma, tumor resection, or congenital defects. Despite a high demand in many clinical fields, until today, no adequate cartilage replacement matrix is available for these fields of application. Materials that are clinically applied for joint cartilage repair still need optimization due to difficult intraoperative handling and risk of early mechanical damage. We have developed and applied a novel chemical process to completely decellularize and sterilize human and porcine cartilage tissues (meniscus cartilage and nasal septum) to generate a new type of bioimplant matrix. To characterize this matrix and to determine the effect of the decellularization process, the content of denatured collagen (w(D)) and the content of glycosaminoglycans (GAGs) (w(G)) were determined. Possible cytotoxic effects and cellular compatibility of the matrix in vitro have been examined by seeding processed cartilage biomatrices with human primary chondrocytes as well as murine fibroblasts (L929). Vitality and state of metabolism of cells were measured using MTS assays. Both cell types adhered to scaffold surfaces and proliferated. No areas of growth inhibition or cytotoxic effects were detected. New synthesis of cartilage-specific extracellular matrix was observed. By histological staining, electron microscopy, and ?CT analysis, an increase of matrix porosity, complete cell elimination, and high GAG removal were demonstrated. Being from natural-origin, processed xenogenic and allogeneic cartilage biomatrices are highly versatile with regard to shape, size, and biomechanics, making them promising candidates for various biomedical applications. PMID:22690787

Schwarz, Silke; Koerber, Ludwig; Elsaesser, Alexander F; Goldberg-Bockhorn, Eva; Seitz, Andreas M; Dürselen, Lutz; Ignatius, Anita; Walther, Paul; Breiter, Roman; Rotter, Nicole

2012-11-01

133

Analytic system matrix resolution modeling in PET: An application to Rb82 cardiac imaging  

Microsoft Academic Search

An area of growing interest in PET imaging has been that of incorporating increasingly more accurate system matrix elements into the reconstruction task, thus arriving at images of higher quality. This work explores application of an analytic approach which individually models and combines the various resolution degrading phenomenon in PET (inter-crystal scattering, inter-crystal penetration, photon non-collinearity and positron range), and

Arman Rahmim; Martin A. Lodge; Jing Tang; Sahel Lashkari; Mohammad Reza Ay

2008-01-01

134

Accelerating matrix decomposition with replications  

Microsoft Academic Search

Matrix decomposition applications that involve large matrix operations can take advantage of the flexibility and adaptability of reconfigurable computing systems to improve performance. The benefits come from replication, which includes vertical replication and horizontal replication. If viewed on a space-time chart, vertical replication allows multiple computations executed in parallel, and horizontal replication renders multiple functions on the same piece of

Yi-gang Tai; Chia-tien Dan Lo; Kleanthis Psarris

2008-01-01

135

Recursive mass matrix factorization and inversion: An operator approach to open- and closed-chain multibody dynamics  

NASA Technical Reports Server (NTRS)

This report advances a linear operator approach for analyzing the dynamics of systems of joint-connected rigid bodies.It is established that the mass matrix M for such a system can be factored as M=(I+H phi L)D(I+H phi L) sup T. This yields an immediate inversion M sup -1=(I-H psi L) sup T D sup -1 (I-H psi L), where H and phi are given by known link geometric parameters, and L, psi and D are obtained recursively by a spatial discrete-step Kalman filter and by the corresponding Riccati equation associated with this filter. The factors (I+H phi L) and (I-H psi L) are lower triangular matrices which are inverses of each other, and D is a diagonal matrix. This factorization and inversion of the mass matrix leads to recursive algortihms for forward dynamics based on spatially recursive filtering and smoothing. The primary motivation for advancing the operator approach is to provide a better means to formulate, analyze and understand spatial recursions in multibody dynamics. This is achieved because the linear operator notation allows manipulation of the equations of motion using a very high-level analytical framework (a spatial operator algebra) that is easy to understand and use. Detailed lower-level recursive algorithms can readily be obtained for inspection from the expressions involving spatial operators. The report consists of two main sections. In Part 1, the problem of serial chain manipulators is analyzed and solved. Extensions to a closed-chain system formed by multiple manipulators moving a common task object are contained in Part 2. To retain ease of exposition in the report, only these two types of multibody systems are considered. However, the same methods can be easily applied to arbitrary multibody systems formed by a collection of joint-connected regid bodies.

Rodriguez, G.; Kreutz, K.

1988-01-01

136

The Application of Architecture Frameworks to Modelling Exploration Operations Costs  

NASA Technical Reports Server (NTRS)

Developments in architectural frameworks and system-of-systems thinking have provided useful constructs for systems engineering. DoDAF concepts, language, and formalisms, in particular, provide a natural way of conceptualizing an operations cost model applicable to NASA's space exploration vision. Not all DoDAF products have meaning or apply to a DoDAF inspired operations cost model, but this paper describes how such DoDAF concepts as nodes, systems, and operational activities relate to the development of a model to estimate exploration operations costs. The paper discusses the specific implementation to the Mission Operations Directorate (MOD) operational functions/activities currently being developed and presents an overview of how this powerful representation can apply to robotic space missions as well.

Shishko, Robert

2006-01-01

137

Evaluation of the Trajectory Operations Applications Software Task (TOAST)  

NASA Technical Reports Server (NTRS)

The Trajectory Operations Applications Software Task (TOAST) is a software development project under the auspices of the Mission Operations Directorate. Its purpose is to provide trajectory operation pre-mission and real-time support for the Space Shuttle program. As an Application Manager, TOAST provides an isolation layer between the underlying Unix operating system and the series of user programs. It provides two main services: a common interface to operating system functions with semantics appropriate for C or FORTRAN, and a structured input and output package that can be utilized by user application programs. In order to evaluate TOAST as an Application Manager, the task was to assess current and planned capabilities, compare capabilities to functions available in commercially-available off the shelf (COTS) and Flight Analysis Design System (FADS) users for TOAST implementation. As a result of the investigation, it was found that the current version of TOAST is well implemented and meets the needs of the real-time users. The plans for migrating TOAST to the X Window System are essentially sound; the Executive will port with minor changes, while Menu Handler will require a total rewrite. A series of recommendations for future TOAST directions are included.

Perkins, Sharon; Martin, Andrea; Bavinger, Bill

1990-01-01

138

Applications of Morphological Operations in Surface Metrology and Dimensional Metrology  

NASA Astrophysics Data System (ADS)

In contrast to the widely used mean-line based evaluation techniques, the capabilities of morphological methods are not fully recognized in practice. Morphological operations, e.g. dilation, erosion, closing and opening, are useful tools in surface metrology and dimensional metrology. This paper presents a variety of novel applications of morphological operations in association with several of existing critical cases to demonstrate their usability and capability. These applications include scanning process analysis, real mechanical surface reconstruction, freeform surface deviation evaluation, open surface and roundness filtration, form approximation, contact phenomenon simulation, establishment of uncertainty zone for continuous surface reconstruction and stratified functional surface evaluation.

Lou, Shan; Jiang, Xiangqian; Scott, Paul J.

2014-03-01

139

Multifunctional Nanotube Polymer Nanocomposites for Aerospace Applications: Adhesion between SWCNT and Polymer Matrix  

NASA Technical Reports Server (NTRS)

Multifunctional structural materials can enable a novel design space for advanced aerospace structures. A promising route to multifunctionality is the use of nanotubes possessing the desired combination of properties to enhance the characteristics of structural polymers. Recent nanotube-polymer nanocomposite studies have revealed that these materials have the potential to provide structural integrity as well as sensing and/or actuation capabilities. Judicious selection or modification of the polymer matrix to promote donor acceptor and/or dispersion interactions can improve adhesion at the interface between the nanotubes and the polymer matrix significantly. The effect of nanotube incorporation on the modulus and toughness of the polymer matrix will be presented. Very small loadings of single wall nanotubes in a polyimide matrix yield an effective sensor material that responds to strain, stress, pressure, and temperature. These materials also exhibit significant actuation in response to applied electric fields. The objective of this work is to demonstrate that physical properties of multifunctional material systems can be tailored for specific applications by controlling nanotube treatment (different types of nanotubes), concentration, and degree of alignment.

Park, Cheol; Wise, Kristopher E.; Kang, Jin Ho; Kim, Jae-Woo; Sauti, Godfrey; Lowther, Sharon E.; Lillehei, Peter T.; Smith, Michael W.; Siochi, Emilie J.; Harrison, Joycelyn S.; Jordan, Kevin

2008-01-01

140

Fire protection system operating experience review for fusion applications  

SciTech Connect

This report presents a review of fire protection system operating experiences from particle accelerator, fusion experiment, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of fire protection system component failure rates and fire accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with these systems are discussed, including spurious operation. This information should be useful to fusion system designers and safety analysts, such as the team working on the Engineering Design Activities for the International Thermonuclear Experimental Reactor.

Cadwallader, L.C.

1995-12-01

141

Web Application Software for Ground Operations Planning Database (GOPDb) Management  

NASA Technical Reports Server (NTRS)

A Web application facilitates collaborative development of the ground operations planning document. This will reduce costs and development time for new programs by incorporating the data governance, access control, and revision tracking of the ground operations planning data. Ground Operations Planning requires the creation and maintenance of detailed timelines and documentation. The GOPDb Web application was created using state-of-the-art Web 2.0 technologies, and was deployed as SaaS (Software as a Service), with an emphasis on data governance and security needs. Application access is managed using two-factor authentication, with data write permissions tied to user roles and responsibilities. Multiple instances of the application can be deployed on a Web server to meet the robust needs for multiple, future programs with minimal additional cost. This innovation features high availability and scalability, with no additional software that needs to be bought or installed. For data governance and security (data quality, management, business process management, and risk management for data handling), the software uses NAMS. No local copy/cloning of data is permitted. Data change log/tracking is addressed, as well as collaboration, work flow, and process standardization. The software provides on-line documentation and detailed Web-based help. There are multiple ways that this software can be deployed on a Web server to meet ground operations planning needs for future programs. The software could be used to support commercial crew ground operations planning, as well as commercial payload/satellite ground operations planning. The application source code and database schema are owned by NASA.

Lanham, Clifton; Kallner, Shawn; Gernand, Jeffrey

2013-01-01

142

Application of Single Phase Matrix Converter Topology in Uninterruptible Power Supply Circuit incorporating Unity Power Factor Control  

Microsoft Academic Search

This paper presents the SPMC topology that operates as an uninterruptible power supply circuit (UPS) incorporating unity power factor control. A single circuit is developed that performs both the rectifier and inverter operation may also incorporate active power filter operation. Commutation strategies are also implemented with reduction in spikes, a common phenomenon in matrix converter topologies. Results of simulations and

Mustafar Kamal Hamzah; Mohamad Fadzil Saidon; S. Z. M. Noor

2006-01-01

143

Metal Matrix Composites Produced by Electroplating. A Review on Technology and Applications  

NASA Astrophysics Data System (ADS)

In this paper selected results of research and development achieved in the Messerschmitt Bölkow Blohm (MBB) Central Laboratory (today part of EADS) within the last four decades will be presented. The focus will concentrate on investigations in the aerospace industry, mainly the production of structures consisting of fibre reinforced metals. By embedding high strength filaments (for example boron fibres) in a ductile metallic matrix (electrodeposited copper, nickel or aluminium) composite materials with excellent strength and stiffness can be produced. By this — on a pilot plant scale — cylindrical metal matrix composite structures have been fabricated and tested and lightweight pressure vessels for future space application (mainly for long time missions) have been produced. The materials, electrolytes, processes and equipment for fabrication and testing of these structures will be presented in detail and the advantages and limitations of the applied processes will be discussed. Beside of this application the technology of electroplating has been used at MBB for the fabrication of dispersion hardened coatings by embedding micro- as well as nano-sized particles in various matrix materials.

Suchentrunk, R.

144

Realization Theoretic Solution of Two Analytic Matrix Equations with Applications to Stabilization of Infinite-Dimensional Systems.  

National Technical Information Service (NTIS)

A realization theoretic approach is proposed for the solutions of two matrix analytic equations arising in the control of infinite-dimensional systems. The realization proposed here is based on the operator theoretic machinery described by Fuhrmann (1981)...

E. Emre J. H. Seo

1988-01-01

145

Applications of membrane unit operations in ethylene process  

Microsoft Academic Search

This work, analyzing a traditional ethylene process, identifies specific applications in this process where membrane technologies can be used to replace typical technologies resulting in some benefits. Design data are provided for several cases along with a discussion on pros and cons of various options referring to a typical cracking plant installed in Europe.Gas separation by means of membrane operations

P. Bernardo; A. Criscuoli; G. Clarizia; G. Barbieri; E. Drioli; G. Fleres; M. Picciotti

2004-01-01

146

Investigation of new communication technologies and its operational application  

Microsoft Academic Search

A description is presented of a Spacelab utilization program concerning studies in the field of communication and navigation. Attention is given to investigations of electromagnetic wave propagation, modulation and bandwidth utilization, integrated communication systems, navigation systems, monitoring experiments, and equipment technology in space. Basic utilization aspects are discussed along with project examples and operational applications.

H. J. Albrecht; D. Rother

1976-01-01

147

Neurocomputing applications in post-operative liver transplant monitoring  

Microsoft Academic Search

This paper explores the potential for the application of neurocomputing technology to the domain of post-operative liver transplant monitoring. The investigation compares a neural network model with two classical statistical techniques using biochemical information obtained from a set of liver transplant patients. Each approach combines the results of a number of liver function tests to predict the presence of allograft

D. G. Melvin; M. Niranjan; R. W. Prager; A. K. Trull; V. F. Hughes

1997-01-01

148

PROGRESS IN THE APPLICATION OF CLASSICAL S-MATRIX THEORY TO INELASTIC COLLISION PROCESSES  

SciTech Connect

Methods are described which effectively solve two of the technical difficulties associated with applying classical S?matrix theory to inelastic/reactive scattering. Specifically, it is shown that rather standard numerical methods can be used to solve the ’’root search’’ problem (i.e., the nonlinear boundary value problem necessary to impose semiclassical quantum conditions at the beginning and the end of the classical trajectories) and also how complex classical trajectories, which are necessary to describe classically forbidden (i.e., tunneling) processes, can be computed in a numerically stable way. Application is made to vibrational relaxation of H{sub 2} by collision with He (within the helicity conserving approximation). The only remaining problem with regard to applying classical S?matrix theory to complex collision processes has to do with the availability of multidimensional uniform asymptotic formulas for interpolating the ’’primitive’’ semiclassical expressions between their various regions of validity.

McCurdy, C.William; Miller, William H.

1980-05-01

149

Applications of matrix-assisted laser desorption fourier transform mass spectrometry for biomolecules  

NASA Astrophysics Data System (ADS)

Matrix-assisted laser desorption FTMS provides a powerful technique for the generation and structural characterization of normal and modified oligonucleotides. Examination of these compounds using 266 nm radiation and a nicotinic acid matrix revealed (M-H)- ions as well as fragment ions which provided structural information. The fragmentation observed resulted primarily from elimination of nucleosides from the 5' end of the oligomers and provided information which could be used to differentiate isomers. Experiments are in progress to extend the application of this ionization technique for larger biomolecules. Preliminary results indicate that ion trapping considerations need to be examined, due to the fact that large laser-generated ions may have significant kinetic energy distributions and may be poorly trapped in the FTMS cell. Current research is directed at determining efficient methods of cooling or decelerating the laser-generated ions.

Hettich, R. L.; Buchanan, M. V.

150

Operational Application of Envisat ASAR in Tropical Production Forest  

NASA Astrophysics Data System (ADS)

A joint research between European Space Agency (ESA) and Bogor Agricultural University (IPB), Indonesia, has been approved under Envisat AO (AO-ID 869). The research is intended to study the operational application of Advanced Synthetic-Aperture Radar (ASAR) for production forest management in Indonesia. Two test sites in forest plantation area of PT Riau Andalan Pulp and Paper (Riaupulp) in Riau Province, Central Sumatera, Indonesia, have been selected recently for the implementation of this joint research. This paper briefs the recent progress of this two-year research (2002-2004) activity. The main objective is to explore the potential of ASAR image analysis application, including POLINSAR, for better and more efficient operational management of tropical plantation forest and its environment. Several interesting operational applications have been identified for the test sites. First application is vegetative cover classification of Acacias, mixed hardwoods, shrubs, oil palms and bare lands. The second is biomass-related application, which study Envisat data on biomass monitoring related to forest plantation. The third is environmental study particularly for site degradation, including issues on monitoring of water bodies and burn site.

Raimadoya, M.; Trisasongko, B.

2003-04-01

151

Development of damped metal-matrix composites for advanced structural applications. Technical report  

SciTech Connect

The development of damped metal matrix composite structures for advanced applications has been investigated by the use of two different approaches: (1) the development of metal matrix composites with high intrinsic damping compared to that of the matrix material, and (2) the development of coated metal matrix composites with high structural damping compared to that of the composite substrates. The two different approaches are analyzed in terms of their potential for improved damping and feasibility for structural applications. Damping was measured by the transverse vibration of free-free beams using the bandwidth technique by a laser vibrometer under ambient conditions. The damping measurements were made over a wide range of frequencies (.7 kHz to 25.6 kHz) at low strain amplitudes (10 to the -10 power to 10 to the -7 power). Materials investigated for their tensile stiffness, strength, and damping performance include mechanically alloyed (MA) Aluminum-Magnesium, SiC(p)/Aluminum-Copper (MA), SiC(p)/AL, AL2O3(p)/AL, SiC(W)/AL, planar random Gr/AL, unidirectional Gr/AL and unidirectional SiC(Nicalon)/AL composites. The effects of coatings of high damping metals (nitinol and incramute) on 6061-T6 AL and AL2O3(p)/AL substrates have also been studied. The AL-Mg (MA), SiC(p)/AL (MA), SiC(W)/AL and th AL2O3(p)/AL composites show no significant improvement in damping compared with that of the 6061-T6 AL.

Updike, C.A.; Bhagat, R.B.

1990-04-01

152

Polynorbornene as a low loss matrix material for IR metamaterial applications.  

SciTech Connect

Novel low loss photopatternable matrix materials for IR metamaterial applications were synthesized using the ring opening metathesis polymerization reaction (ROMP) of norbornene followed by a partial hydrogenation to remove most of the IR absorbing olefin groups which absorb in the 8-12 {micro}m range. Photopatterning was achieved via crosslinking of the remaining olefin groups with alpha, omega-dithiols via the thiol-ene coupling reaction. Since ROMP is a living polymerization the molecular weight of the polymer can be controlled simply by varying the ratio of catalyst to monomer. In order to determine the optimum photopattenable IR matrix material we varied the amount of olefin remaining after the partial hydrogenation. Hydrogenation was accomplished using tosyl hydrazide. The degree of hydrogenation can be controlled by altering the reaction time or reaction stoichiometry and the by-products can be easily removed during workup by precipitation into ethanol. Several polymers have been prepared using this reduction scheme including two polymers which had 54% and 68% olefin remaining. Free standing films (approx. 12 {micro}m) were prepared from the 68% olefin material using draw-down technique and subsequently irradiated with a UV lamp (365 nm) for thirty minutes to induce crosslinking via thiol-ene reaction. After crosslinking, the olefin IR-absorption band disappeared and the Tg of the matrix material increased; both desirable properties for IR metamaterial applications. The polymer system has inherent photopatternable behavior primarily because of solubility differences between the pre-polymer and cross-linked matrix. Photopatterned structures using the 54% as well as the 68% olefin material were easily obtained. The synthesis, processing, and IR absorption data and the ramifications to dielectric metamaterials will be discussed.

Arrington, Christian Lew; Sinclair, Michael B.; Ginn, James Cleveland, III; Lee, Yun-Ju; Sanchez, Andrea E.; Clem, Paul Gilbert; Hines, Paul; Dirk, Shawn M.; Rasberry, Roger D.

2010-11-01

153

Engineering the extracellular matrix for clinical applications: endoderm, mesoderm, and ectoderm.  

PubMed

Tissue engineering is rapidly progressing from a research-based discipline to clinical applications. Emerging technologies could be utilized to develop therapeutics for a wide range of diseases, but many are contingent on a cell scaffold that can produce proper tissue ultrastructure. The extracellular matrix, which a cell scaffold simulates, is not merely a foundation for tissue growth but a dynamic participant in cellular crosstalk and organ homeostasis. Cells change their growth rates, recruitment, and differentiation in response to the composition, modulus, and patterning of the substrate on which they reside. Cell scaffolds can regulate these factors through precision design, functionalization, and application. The ideal therapy would utilize highly specialized cell scaffolds to best mimic the tissue of interest. This paper discusses advantages and challenges of optimized cell scaffold design in the endoderm, mesoderm, and ectoderm for clinical applications in tracheal transplant, cardiac regeneration, and skin grafts, respectively. PMID:24390851

Williams, Miguel L; Bhatia, Sujata K

2014-03-01

154

Completeness of the system of eigenvectors of off-diagonal operator matrices and its applications in elasticity theory  

NASA Astrophysics Data System (ADS)

This paper deals with off-diagonal operator matrices and their applications in elasticity theory. Two kinds of completeness of the system of eigenvectors are proven, in terms of those of the compositions of two block operators in the off-diagonal operator matrices. Using these results, the double eigenfunction expansion method for solving upper triangular matrix differential systems is proposed. Moreover, we apply the method to the two-dimensional elasticity problem and the problem of bending of rectangular thin plates on elastic foundation.

Huang, Jun-Jie; Alatancang; Wang, Hua

2010-12-01

155

Operating principles of an electrothermal vibrometer for optical switching applications  

NASA Astrophysics Data System (ADS)

A compact polysilicon surface-micromachined microactuator designed for optical switching applications is described. This actuator is fabricated using the foundry MUMPs process provided by Cronos Integrated Microsystems Inc. Actuated electrothermally, the microactuator allows fast switching speeds and can be operated with a low voltage square-wave signal. The design, operation mechanisms for this long-range and high frequency thermal actuation are described. A vertical micromirror integrated with this actuator can be operated with a 10.5 V, 20 kHz 15% duty-cycle pulse signal, achieving a lateral moving speed higher than 15.6 mm/sec. The optical switch has been operated to frequencies as high as 30 kHz.

Pai, Minfan; Tien, Norman C.

1999-09-01

156

Application of AI techniques to blast furnace operations  

SciTech Connect

It was during the first stages of application of artificial intelligence (AI) to industrial fields, that the ironmaking division of Mizushima works at Kawasaki Steel recognized its potential. Since that time, the division has sought applications for these techniques to solve various problems. AI techniques applied to control the No. 3 blast furnace operations at the Mizushima works include: Blast furnace control by a diagnostic type of expert system that gives guidance to the actions required for blast furnace operation as well as control of furnace heat by automatically setting blast temperature; Hot stove combustion control by a combination of fuzzy inference and a physical model to insure good thermal efficiency of the stove; and blast furnace burden control using neural networks makes it possible to connect the pattern of gas flow distribution with the condition of the furnace. Experience of AI to control the blast furnace and other ironmaking operations has proved its capability for achieving automation and increased operating efficiency. The benefits are very high. For these reasons, the applications of AI techniques will be extended in the future and new techniques studied to further improve the power of AI.

Iida, Osamu; Ushijima, Yuichi; Sawada, Toshiro [Kawasaki Steel Corp., Kurashiki (Japan)

1995-10-01

157

Underwater application of nasal decongestants: method for special operations.  

PubMed

A simple method of emergency underwater application of a nasal decongestant in divers to prevent diving-related accidents or even fatalities attributable to sequelae of middle-ear and sinus barotrauma of ascent was evaluated. Eleven military divers had to inject 1 mL of 0.02% methylene blue into a central venous catheter after having inserted the tip between their upper lip and the mask at 1 m depth in a pool. After injection, the head had to be reclined. Blue liquid flowing from a diver's nostril and a "bitter" taste sensation reported immediately after surfacing indicated successful application. All divers were observed to have had blue liquid flowing from the nostril of application, and one diver could not describe the taste. This method of underwater application of nasal decongestants may be useful for emergency prevention in divers, especially during covert operations. Underwater availability of the system in a special kit carried by divers would be required. PMID:11143432

Mutzbauer, T S; Mueller, P H; Sigg, O; Tetzlaff, K; Neubauer, B

2000-11-01

158

T matrix of the homogeneous anisotropic sphere: applications to orientation-averaged resonant scattering  

NASA Astrophysics Data System (ADS)

We illustrate some numerical applications of a recently derived semianalytic method for calculating the T matrix of a sphere composed of an arbitrary anisotropic medium with or without losses. This theory is essentially an extension of Mie theory of the diffraction by an isotropic sphere. We use this theory to verify a long-standing conjecture by Bohren and Huffman that the extinction cross section of an orientation-averaged anisotropic sphere is not simply the average of the extinction cross sections of three isotropic spheres, each having a refractive index equal to that of one of the principal axes.

Stout, Brian; Nevière, Michel; Popov, Evgeny

2007-04-01

159

Cryogenic system operating experience review for fusion applications  

SciTech Connect

This report presents a review of cryogenic system operating experiences, from particle accelerator, fusion experiment, space research, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of cryogenic component failure rates and accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with cryogenic systems are discussed, including ozone formation, effects of spills, and modeling spill behavior. This information should be useful to fusion system designers and safety analysts, such as the team working on the International Thermonuclear Experimental Reactor design.

Cadwallader, L.C.

1992-01-01

160

Coiled-tubing applications for blowout-control operations  

SciTech Connect

Coiled-tubing drilling is now being used in various operations. Its complete field of applications is not currently established. Coiled tubing used for well control while drilling is a new field where its limits are being explored. This paper provides guidelines on topics to be considered in determining the applicability of coiled tubing for well-control problems. The information provided is based on recent field experiences with several well-control problems when drilling vent and relief wells. In some cases, coiled-tubing drilling capabilities, by necessity, were significantly extended beyond levels the industry considered to be upper limits. Well control cannot always be handled by coiled tubing. It is a special-application tool that can handle many situations and is, in some cases, clearly the optimum choice for the application. This paper presents guidelines for selecting coiled tubing for each application and discusses economics. It also describes coiled-tubing operations for regaining control of blowout wells in certain situations and gives technical requirements for planning and executing these types of jobs. Case histories where coiled-tubing units (CTU`s) have been used to regain control of drilling and producing wells are provided for illustration.

Adams, N.J. [Neal Adams Firefighters Inc., Houston, TX (United States); Mack, S.K.; Fannin, V.R.; Rocchi, T.

1996-05-01

161

Gas turbine compressor unit application in sour gas field operation  

SciTech Connect

The use of sour gas as primary energy requires constant supply pressure and flow to the gas treatment plant as well as to the pipeline distribution network and consumers. During exploitation of gas fields, when the well head pressure and flow decreases, production continues at increased cost. Application of gas compression equipment is required for continuation of supply pressure and flow to the sour gas treatment plant and to customer connection flanges. The design and layout of sour gas compression equipment has to guarantee high operational availability and reliability for continuous duty. To properly select equipment for sour gas applications, including the compressor, its driver and auxiliary and ancillary systems, the specific requirements and standards have to be taken into consideration. This paper reports about a situation in the sour gas fields in the northern part of West Germany and will describe the design objectives, station layout and equipment selection for a sour gas compressor station including operating experiences.

Schmidt, K.D.; Scholz, W.; Schluter, H.

1986-01-01

162

Generalized complement operators and applications in some semirings  

NASA Astrophysics Data System (ADS)

Generalized complement operators on the semiring of all Boolean matrices as semilattice homomorphisms are considered. Some applications in solving equations on the set Bn of all binary relations are developed. In particular the structure of B3 is investigated by computer methods. Specific properties of the subsemigroup generated by all irregular relations in B3 are found. Stochastic experiments on the monoid Bn were made. The frequency of irregular elements as well as those of solvable equations depending on n is examined.

Bijev, G.

2013-12-01

163

The automated Matrix-Element reweighting and its applications at the LHC  

NASA Astrophysics Data System (ADS)

Given a sample of experimental events and a set of theoretical models, the matrix element method (MEM) is a procedure to select the most plausible model that governs the production of these events. From a theoretical point of view, it is probably the most powerful multi-variate analysis technique since it maximally uses the information contained in the Feynman amplitudes. This technique is now widely known since it has been used for the precision top mass measurement at Tevatron, for example. The MadWeight software is presented. MadWeight is a phase-space generator designed for the automated numerical estimation of matrix elements based on MadGraph amplitudes. With the modern computing resources, it allows the large-scale deployment of the MEM technique on high-statistics data and simulated samples. Several applications of the method at LHC are discussed, including the measurement of the spin and parity of the recently discovered boson, signal-to-background discrimination, full differential spectrum estimation and other promising applications.

Mertens, Alexandre

2014-06-01

164

High-performance ab initio density matrix renormalization group method: Applicability to large-scale multireference problems for metal compounds  

NASA Astrophysics Data System (ADS)

This article presents an efficient and parallelized implementation of the density matrix renormalization group (DMRG) algorithm for quantum chemistry calculations. The DMRG method as a large-scale multireference electronic structure model is by nature particularly efficient for one-dimensionally correlated systems, while the present development is oriented toward applications for polynuclear transition metal compounds, in which the macroscopic one-dimensional structure of electron correlation is absent. A straightforward extension of the DMRG algorithm is proposed with further improvements and aggressive optimizations to allow its application with large multireference active space, which is often demanded for metal compound calculations. Special efficiency is achieved by making better use of sparsity and symmetry in the operator and wave function representations. By accomplishing computationally intensive DMRG calculations, the authors have found that a large number of renormalized basis states are required to represent high entanglement of the electron correlation for metal compound applications, and it is crucial to adopt auxiliary perturbative correction to the projected density matrix during the DMRG sweep optimization in order to attain proper convergence to the solution. Potential energy curve calculations for the Cr2 molecule near the known equilibrium precisely predicted the full configuration interaction energies with a correlation space of 24 electrons in 30 orbitals [denoted by (24e,30o)]. The energies are demonstrated to be accurate to 0.6mEh (the error from the extrapolated best value) when as many as 10 000 renormalized basis states are employed for the left and right DMRG block representations. The relative energy curves for [Cu2O2]2+ along the isomerization coordinate were obtained from DMRG and other correlated calculations, for which a fairly large orbital space (32e,62o) is modeled as a full correlation space. The DMRG prediction nearly overlaps with the energy curve from the coupled cluster with singles, doubles, and perturbative triple [CCSD(T)] calculations, while the multireference complete active space self-consistent field (CASSCF) calculations with the small reference configuration (8e,8o) are found to overestimate the biradical character of the electronic state of [Cu2O2]2+ according to the one-electron density matrix analysis.

Kurashige, Yuki; Yanai, Takeshi

2009-06-01

165

Lorentz-covariant surface impedance and characteristic matrix methods with applications to measurements of material parameters of linear media  

Microsoft Academic Search

The impedance and characteristics matrix methods are generalized on the case of uniformly moving linear media. On this basis, the reflection and transmission operators of the boundary of two anisotropic and gyrotropic media uniformly moving with different velocities, and similar operators of a multilayer structure consisting of such media, are found. The suggested four-dimensional formalism is very useful also in

G. N. Borzdov

1992-01-01

166

SMES application for frequency control during islanded microgrid operation  

NASA Astrophysics Data System (ADS)

This paper analyzes the operating characteristics of a superconducting magnetic energy storage (SMES) for the frequency control of an islanded microgrid operation. In the grid-connected mode of a microgrid, an imbalance between power supply and demand is solved by a power trade with the upstream power grid. The difference in the islanded mode is a critical problem because the microgrid is isolated from any power grid. For this reason, the frequency control during islanded microgrid operation is a challenging issue. A test microgrid in this paper consisted of a wind power generator, a PV generation system, a diesel generator and a load to test the feasibility of the SMES for controlling frequency during islanded operation as well as the transient state varying from the grid-connected mode to the islanded mode. The results show that the SMES contributes well for frequency control in the islanded operation. In addition, a dual and a single magnet type of SMES have been compared to demonstrate the control performance. The dual magnet has the same energy capacity as the single magnet, but there are two superconducting coils and each coil has half inductance of the single magnet. The effectiveness of the SMES application with the simulation results is discussed in detail.

Kim, A.-Rong; Kim, Gyeong-Hun; Heo, Serim; Park, Minwon; Yu, In-Keun; Kim, Hak-Man

2013-01-01

167

Gloved hand as applicator of antiseptic to operation sites.  

PubMed

A 95% ethanol solution containing 0-5% chlorhexidine digluconate caused a significantly greater mean reduction in skin bacteria (99-9% plus or minus 0-024) when rubbed by a gloved hand on to the skin of one hand for two minutes than when applied to the same area for the same time with the traditional gauze applicator for operation sites (90-7% plus or minus 2-12). The latter reduction, however, was greater than that reported in five previous experiments in which application of the same solution for the same time to two hands gave mean reductions varying from 79% to 84%. An aqueous solution and a 70% alcoholic solution of chlorhexidine also gave significantly greater reduction (and alcoholic povidone iodine almost significantly greater reduction) when applied by a gloved hand than on gauze. It is inferred that the effectiveness of skin disinfection depends both on the antiseptic used and on the manner of application, and varies with the amount of friction used in applying the antiseptic. Further studies on disinfection of the surgeon's hands with 0-5% chlorhexidine in 95% alcohol rubbed on and allowed to dry have supported its value and acceptability; the mean bacterial counts of washings from gloves of surgeons after operations were lower after the use of this method than after other preoperative preparations of the hands. PMID:49746

Lowbury, E J; Lilly, H A

1975-07-26

168

Flexible matrix composites: Dynamic characterization, modeling, and potential for driveshaft applications  

NASA Astrophysics Data System (ADS)

Flexible matrix composites (FMCs) utilize the high elongation capability of elastomers such as polyurethane to withstand large strains in the direction transverse to the fiber reinforcement while retaining strength and stiffness in the longitudinal direction. FMCs are highly anisotropic and can therefore be tailored to achieve distinctive mechanical characteristics that are difficult to obtain using conventional rigid matrix composites. In the current study, the potential of using an FMC to construct a flexurally-soft, torsionally-stiff driveshaft is examined. The FMC selected for the current investigation is a carbon fiber/polyurethane matrix material system. Both quasi-static and dynamic tests have been performed to characterize the properties of the FMC material. By modeling viscoelastic FMC lamina properties with a fractional derivative approach, a novel damping model that accounts for the frequency and temperature dependence of the FMC material is developed. This is the first time fractional derivative model has been applied to a fiber composite. Good agreement between the damping model and experimental data for angle-ply tubes was obtained. Based on the validated damping model, a self-heating model to predict the temperature increase caused by internal damping of a FMC shaft under misaligned rotation is also proposed. A laboratory-scale, misaligned FMC shaft rotation test stand was built to validate the proposed model. Good agreement is shown between the self-heating model predictions and experiment results. This model can be valuable in the selection of constituent materials for FMCs and also in the design of FMC shafts. Preliminary fatigue test results show that FMC materials have potentially good fatigue performance in shaft applications.

Shan, Ying

169

Properties of graphite fiber reinforced copper matrix composites for space power applications  

NASA Technical Reports Server (NTRS)

The thermal and mechanical properties of pitch-based graphite fiber reinforced copper matrix (Gr/Cu) composites usable for space applications such as radiator fins were investigated. Thermal conductivity was measured as a function of fiber volume fraction and architecture. Results showed for unidirectional P-100 Gr/Cu composites, the longitudinal thermal conductivity was nearly independent of fiber volume fraction. Transverse thermal conductivities (perpendicular to the fibers) were strongly affected by the fiber volume fraction with higher volume fractions resulting in lower thermal conductivities. The effect of architecture on thermal conductivity followed the cosine squared law for simple architectures. Insufficient data are available currently to model more complex architectures, but adding fibers in the direction of the heat flow increases the thermal conductivity as low conductivity plies are supplemented by high conductivity plies. Thermal expansion tests were conducted on the Gr fibers and Gr/Cu composites. The results show a considerable thermal expansion mismatch between the fibers and the Cu matrix. The longitudinal thermal expansion showed a strong dependence on the architecture of the Gr/Cu composites. The composites also show a thermal expansion hysteresis. The hysteresis was eliminated by an engineered interface. Mechanical testing concentrated on the dynamic modulus and strength of the composites. The dynamic modulus of the Gr/Cu composites was 305 GPa up to 400 C, a value equivalent to Be. The strengths of the composites were less than expected, but this is attributed to the poor bond across the interface between the Gr fibers and Cu matrix. Testing of composites with an engineered interface is expected to yield strengths nearer the values predicted by the rule of mixtures.

Ellis, David L.

1992-01-01

170

Application of acellular dermal matrix for intestinal elongation in animal models  

PubMed Central

AIM: To investigate the efficacy of acellular dermal matrix (ADM) for intestinal elongation in animal models. METHODS: Japanese white big-ear rabbits (n = 9) and Wuzhishan miniature pigs (n = 5) were used in the study. Home-made and commercial ADM materials were used as grafts, respectively. A 3-cm long graft was interposed in continuity with the small bowel and a side-to-side anastomosis, distal to the graft about 3-4 cm, was performed. The animals were sacrificed at 2 wk, 4 wk, 8 wk and 3 mo after surgery and the histological changes were evaluated under light microscope and electron microscope. RESULTS: The animals survived after the operation with no evidence of peritonitis and sepsis. Severe adhesions were found between the graft and surrounding intestine. The grafts were completely absorbed within postoperative two or three months except one. Histological observation showed inflammation in the grafts with fibrinoid necroses, infiltration of a large amount of neutrophils and leukomonocytes, and the degree varied in different stages. The neointestine with well-formed structures was not observed in the study. CONCLUSION: It is not suitable to use acellular dermal matrix alone as a scaffold for the intestinal elongation in animal models.

Xu, Hui-Min; Wang, Zhen-Jun; Han, Jia-Gang; Ma, Hua-Chong; Zhao, Bo; Zhao, Bao-Cheng

2010-01-01

171

A matrix-form GSM-CFD solver for incompressible fluids and its application to hemodynamics  

NASA Astrophysics Data System (ADS)

A GSM-CFD solver for incompressible flows is developed based on the gradient smoothing method (GSM). A matrix-form algorithm and corresponding data structure for GSM are devised to efficiently approximate the spatial gradients of field variables using the gradient smoothing operation. The calculated gradient values on various test fields show that the proposed GSM is capable of exactly reproducing linear field and of second order accuracy on all kinds of meshes. It is found that the GSM is much more robust to mesh deformation and therefore more suitable for problems with complicated geometries. Integrated with the artificial compressibility approach, the GSM is extended to solve the incompressible flows. As an example, the flow simulation of carotid bifurcation is carried out to show the effectiveness of the proposed GSM-CFD solver. The blood is modeled as incompressible Newtonian fluid and the vessel is treated as rigid wall in this paper.

Yao, Jianyao; Liu, G. R.

2014-02-01

172

Test Waveform Applications for JPL STRS Operating Environment  

NASA Technical Reports Server (NTRS)

This software demonstrates use of the JPL Space Telecommunications Radio System (STRS) Operating Environment (OE), tests APIs (application programming interfaces) presented by JPL STRS OE, and allows for basic testing of the underlying hardware platform. This software uses the JPL STRS Operating Environment ["JPL Space Tele com - munications Rad io System Operating Environment,"(NPO-4776) NASA Tech Briefs, commercial edition, Vol. 37, No. 1 (January 2013), p. 47] to interact with the JPL-SDR Software Defined Radio developed for the CoNNeCT (COmmunications, Navigation, and Networking rEconfigurable Testbed) Project as part of the SCaN Testbed installed on the International Space Station (ISS). These are the first applications that are compliant with the new NASA STRS Architecture Standard. Several example waveform applications are provided to demonstrate use of the JPL STRS OE for the JPL-SDR platform used for the CoNNeCT Project. The waveforms provide a simple digitizer and playback capability for the SBand RF slice, and a simple digitizer for the GPS slice [CoNNeCT Global Positioning System RF Module, (NPO-47764) NASA Tech Briefs, commercial edition, Vol. 36, No. 3 (March 2012), p. 36]. These waveforms may be used for hardware test, as well as for on-orbit or laboratory checkout. Additional example waveforms implement SpaceWire and timer modules, which can be used for time transfer and demonstration of communication between the two Xilinx FPGAs in the JPLSDR. The waveforms are also compatible with ground-based use of the JPL STRS OE on radio breadboards and Linux.

Lux, James P.; Peters, Kenneth J.; Taylor, Gregory H.; Lang, Minh; Stern, Ryan A.; Duncan, Courtney B.

2013-01-01

173

Ground Operations Aerospace Language (GOAL). Volume 5: Application Studies  

NASA Technical Reports Server (NTRS)

The Ground Operations Aerospace Language (GOAL) was designed to be used by test oriented personnel to write procedures which would be executed in a test environment. A series of discussions between NASA LV-CAP personnel and IBM resulted in some peripheral tasks which would aid in evaluating the applicability of the language in this environment, and provide enhancement for future applications. The results of these tasks are contained within this volume. The GOAL vocabulary provides a high degree of readability and retainability. To achieve these benefits, however, the procedure writer utilizes words and phrases of considerable length. Brief form study was undertaken to determine a means of relieving this burden. The study resulted in a version of GOAL which enables the writer to develop a dialect suitable to his needs and satisfy the syntax equations. The output of the compiler would continue to provide readability by printing out the standard GOAL language. This task is described.

1973-01-01

174

Magnetic thrust bearing operation and industrial pump application  

SciTech Connect

Magnetic bearings represent a new bearing technology, which has some advantages over conventional fluid film and rolling element bearings for some applications. The paper describes the basic concepts of magnetic thrust bearing operation involving the magnetic actuator, electronic controls, power amplifier, and sensor. The magnetic actuator is a magnetic circuit, which generates attractive forces. These support the rotating shaft. While it is often thought that magnetic bearings are highly nonlinear devices, this paper demonstrates that they are linear in both the perturbation flux and current when used in a double acting configuration. Electronic feedback controls are used to stabilize the bearing. Example design parameters are presented for an application to an industrial canned motor pump.

Allaire, P.E.; Maslen, E.H.; Lewis, D.W.; Flack, R.D. [Univ. of Virginia, Charlottesville, VA (United States)

1997-01-01

175

Improvements in sparse matrix/vector technique applications for on-line load flow calculation  

SciTech Connect

Sparsity technique is applied to a wide range of problems in power systems analysis. In this paper the authors propose several analytical and computational improvements in sparsity applications. The new partial matrix refactorization method and ordering algorithm are presented. The proposed method is very efficient when applied to various kinds of programs, such as: on-line load flow, optimal power flow and steady-state security analysis. The proposed methodology is applied in a fast decoupled load flow program which include the treatment of tap violations on under-load tap changing (ULTC) transformers and reactive power generation on PV buses. Effects of proposed improvements are well tested and documented on the three networks: 118 bus IEEE test network and two utility networks with 209 and 519 buses, respectively. Keywords: sparsity technique, load flow analysis, security analysis.

Ristanovic, P.; Bjelogrlic, M.; Babic, B.S.

1989-02-01

176

SiC/SiC Ceramic Matrix Composites Developed for High-Temperature Space Transportation Applications  

NASA Technical Reports Server (NTRS)

Researchers at the NASA Glenn Research Center have been developing durable, high-temperature ceramic matrix composites (CMCs) with silicon carbide (SiC) matrices and SiC or carbon fibers for use in advanced reusable launch vehicle propulsion and airframe applications in the Next Generation Launch Technology (NGLT) Program. These CMCs weigh less and are more durable than competing metallic alloys, and they are tougher than silicon-based monolithic ceramics. Because of their high specific strength and durability at high temperatures, CMCs such as C/SiC (carbon- fiber-reinforced silicon carbide) and SiC/SiC (silicon-carbide-fiber-reinforced silicon carbide) may increase vehicle performance and safety significantly and reduce the cost of transporting payloads to orbit.

Kiser, J. Douglas; Bhatt, Ramakrishna, T.; Morscher, Gregory N.; Yun, Hee Mann; DiCarlo, James A.; Petko, Jeanne F.

2005-01-01

177

A SAR multilook optronic processor for operational Earth monitoring applications  

NASA Astrophysics Data System (ADS)

Synthetic Aperture Radar (SAR) is the only remote sensing technology that can provide high resolution images in adverse weather conditions and in day or night times. It is thus is a powerful tool for Earth monitoring. Certain applications, such as disaster relief, military reconnaissance and ice-flow and ship monitoring require a continuous flow of high-resolution images covering large areas; however, given the large amount of complex data generated and system limitations of data bandwidth and processing speed, not all the requirements can be met at the same time. In addition, multiple user requests are often submitted to the SAR system platform, and not all can be addressed, again due to limitations of area coverage. Increasing the speed of SAR processors and processing on-board are two ways to improve the SAR data throughput and therefore to meet the operational needs of all users. This paper discusses an optronic SAR processor capable of rapidly processing full-scene multi-looked images. Details of the processor design and image results are discussed. Estimations for speed and image throughput are provided, all presented in the context of the requirements for operational service of the various applications.

Marchese, Linda; Bourqui, Pascal; Turgeon, Sandra; Doucet, Michel; Vachon, Carl; Harnisch, Bernd; Suess, Martin; Châteauneuf, François; Bergeron, Alain

2010-10-01

178

Medical Applications of White LEDs for Surgical Operation  

NASA Astrophysics Data System (ADS)

Everywhere in the world, the highest quality and quantity of lighting is required during the surgical operations. However, the surgical approach has had many types and various angles, common ceiling surgical halogen lighting system cannot provide an adequate amount of beams because the surgeons' heads hinder the illuminations from reaching the operation field. The evolution of solid-state-lighting is currently going to be developed due to the progress of white light emitting diodes (LEDs). We proposed and developed the new lighting equipment that is a surgical lighting goggle composed of InGaN-YAG (yttrium aluminum garnet):Ce3+-based white LEDs. Here, we newly design surgical lighting system composed of white LEDs equipped on both sides of goggles. In fact, we have succeeded in the first internal shunt operation in the left forearm using the surgical LED lighting system on 11th Sept 2000. Since the white LEDs used were composed of InGaN-blue-emitters and YAG-yellow-phosphors, the color rendering property was not sufficient in the reddish colors. After our first challenge for medical application of white LEDs, we have been trying to improve the luminance power of white LED, the color rendering in red colors and the spectral distribution of white LED to render inherent color of raw flesh such as skin, blood, fat tissue and internal organs. We have produced new concepts for LED lighting sources and new several generations of LED lighting goggles.

Shimada, Junichi; Kawakami, Yoichi

179

Evaluation of Ceramic Matrix Composite Technology for Aircraft Turbine Engine Applications  

NASA Technical Reports Server (NTRS)

The goals of the NASA Environmentally Responsible Aviation (ERA) Project are to reduce the NO(x) emissions, fuel burn, and noise from turbine engines. In order to help meet these goals, commercially-produced ceramic matrix composite (CMC) components and environmental barrier coatings (EBCs) are being evaluated as parts and panels. The components include a CMC combustor liner, a CMC high pressure turbine vane, and a CMC exhaust nozzle as well as advanced EBCs that are tailored to the operating conditions of the CMC combustor and vane. The CMC combustor (w/EBC) could provide 2700 F temperature capability with less component cooling requirements to allow for more efficient combustion and reductions in NOx emissions. The CMC vane (w/EBC) will also have temperature capability up to 2700 F and allow for reduced fuel burn. The CMC mixer nozzle will offer reduced weight and improved mixing efficiency to provide reduced fuel burn. The main objectives are to evaluate the manufacturability of the complex-shaped components and to evaluate their performance under simulated engine operating conditions. Progress in CMC component fabrication, evaluation, and testing is presented in which the goal is to advance from the proof of concept validation (TRL 3) to a system/subsystem or prototype demonstration in a relevant environment (TRL 6).

Halbig, Michael C.; Jaskowiak, Martha H.; Kiser, James D.; Zhu, Dongming

2013-01-01

180

Application of 3 × 3 transformation matrix in the correction of three-dimensional AFM image tilts through coordinate transformation.  

PubMed

In atomic force microscopy (AFM), it is difficult to maintain samples in a perfect horizontal position on the piezoelectric stage of an AFM to obtain accurate measurement of surface features and to enhance the visual effect of topographic images. Correction of the tilted image therefore requires the use of an appropriate 3 × 3 transformation matrix which will transform the coordinates to simultaneously correct the tilt in both the x-and y-axes due to the three-dimensional nature of AFM images. In this study, application of transformation matrix in three-dimensions for the simultaneous correction of image tilts in both the x- and y-axes by the method of coordinate transformation in three-dimensions is presented. Application of the matrix in simultaneously correcting tilts in the x- and y-axes of an AFM image is implemented by simulating an image assuming there are tilts in both the x- and y-axes. Results of features measurement after transforming the coordinates with the matrix show the efficacy of the matrix. This will conveniently replace the line-by-line analysis done to remove tilts in AFM, which has been the practice long before now. It also has the advantage of correcting images by simultaneously removing tilts in both the x- and y-axes as a veritable replacement of having to separately correcting tilts in images. This matrix can be used to transform coordinates in three-dimensions to obtain accurate step height and linewidth in AFM images. PMID:21455951

Adebayo, Adedayo S; Zhao, Xue-zeng; Wang, Fei; Zhou, Faquan

2011-01-01

181

Network latency and operator performance in teleradiology applications.  

PubMed

Teleradiology applications often use an interactive conferencing mode with remote control mouse pointers. When a telephone is used for voice communication, latencies of the data network can create a temporal discrepancy between the position of the mouse pointer and the verbal communication. To assess the effects of this dissociation, we examined the performance of 5 test persons carrying out simple teleradiology tasks under varying simulated network conditions. When the network latency exceeded 400 milliseconds, the performance of the test persons dropped, and an increasing number of errors were made. This effect was the same for constant latencies, which can occur on the network path, and for variable delays caused by the Nagle algorithm, an internal buffering scheme used by the TCP/IP protocol. Because the Nagle algorithm used in typical TCP/IP implementations causes a latency of about 300 milliseconds even before a data packet is sent, any additional latency in the network of 100 milliseconds or more will result in a decreased operator performance in teleradiology applications. These conditions frequently occur on the public Internet or on overseas connections. For optimal performance, the authors recommend bypassing the Nagle algorithm in teleradiology applications. PMID:15359750

Stahl, J N; Tellis, W; Huang, H K

2000-08-01

182

New algorithm for solving block matrix equations with applications in 2-D AR spectral estimation  

Microsoft Academic Search

The author presents an iterative algorithm to solve Toeplitz and non-Toeplitz block matrix equations. The development is based upon some well-known matrix iterative techniques. The algorithm is developed for the ideal case where the individual blocks in the autocorrelation matrix are Toeplitz, and it is then extended to a more general least squares data formulation case. It is shown that

Murali Tummala

1991-01-01

183

Improved estimation of the covariance matrix of stock returns with an application to portfolio selection  

Microsoft Academic Search

This paper proposes to estimate the covariance matrix of stock returns by an optimally weighted average of two existing estimators: the sample covariance matrix and single-index covariance matrix. This method is generally known as shrinkage, and it is standard in decision theory and in empirical Bayesian statistics. Our shrinkage estimator can be seen as a way to account for extra-market

Olivier Ledoit; Michael Wolf

2003-01-01

184

GIS applications for military operations in coastal zones  

NASA Astrophysics Data System (ADS)

In order to successfully support current and future US military operations in coastal zones, geospatial information must be rapidly integrated and analyzed to meet ongoing force structure evolution and new mission directives. Coastal zones in a military-operational environment are complex regions that include sea, land and air features that demand high-volume databases of extreme detail within relatively narrow geographic corridors. Static products in the form of analog maps at varying scales traditionally have been used by military commanders and their operational planners. The rapidly changing battlefield of 21st Century warfare, however, demands dynamic mapping solutions. Commercial geographic information system (GIS) software for military-specific applications is now being developed and employed with digital databases to provide customized digital maps of variable scale, content and symbolization tailored to unique demands of military units. Research conducted by the Center for Remote Sensing and Mapping Science at the University of Georgia demonstrated the utility of GIS-based analysis and digital map creation when developing large-scale (1:10,000) products from littoral warfare databases. The methodology employed-selection of data sources (including high resolution commercial images and Lidar), establishment of analysis/modeling parameters, conduct of vehicle mobility analysis, development of models and generation of products (such as a continuous sea-land DEM and geo-visualization of changing shorelines with tidal levels)-is discussed. Based on observations and identified needs from the National Geospatial-Intelligence Agency, formerly the National Imagery and Mapping Agency, and the Department of Defense, prototype GIS models for military operations in sea, land and air environments were created from multiple data sets of a study area at US Marine Corps Base Camp Lejeune, North Carolina. Results of these models, along with methodologies for developing large-scale littoral warfare databases, aid the National Geospatial-Intelligence Agency in meeting littoral warfare analysis, modeling and map generation requirements for US military organizations.

Fleming, S.; Jordan, T.; Madden, M.; Usery, E. L.; Welch, R.

185

Application of non-negative matrix factorization to multispectral FLIM data analysis  

PubMed Central

Existing methods of interpreting fluorescence lifetime imaging microscopy (FLIM) images are based on comparing the intensity and lifetime values at each pixel with those of known fluorophores. This method becomes unwieldy and subjective in many practical applications where there are several fluorescing species contributing to the bulk fluorescence signal, and even more so in the case of multispectral FLIM. Non-negative matrix factorization (NMF) is a multivariate data analysis technique aimed at extracting non-negative signatures of pure components and their non-negative abundances from an additive mixture of those components. In this paper, we present the application of NMF to multispectral time-domain FLIM data to obtain a new set of FLIM features (relative abundance of constituent fluorophores). These features are more intuitive and easier to interpret than the standard fluorescence intensity and lifetime values. The proposed approach, unlike several FLIM data analysis methods, is not limited by the number of constituent fluorescing species or their possibly complex decay dynamics. Moreover, the new set of FLIM features can be obtained by processing raw multispectral FLIM intensity data, thereby rendering time deconvolution unnecessary and resulting in lesser computational time and relaxed SNR requirements. The performance of the NMF method was validated on simulated and experimental multispectral time-domain FLIM data. The NMF features were also compared against the standard intensity and lifetime features, in terms of their ability to discriminate between different types of atherosclerotic plaques.

Pande, Paritosh; Applegate, Brian E.; Jo, Javier A.

2012-01-01

186

Design of triangular FBG filter for sensor applications using covariance matrix adapted evolution algorithm  

NASA Astrophysics Data System (ADS)

The design of triangular fiber Bragg grating (TFBG) filters using covariance matrix adapted evolution strategy (CMAES) algorithm is presented. The TFBG filter can be used as a readout device in FBG-based sensor applications. Two different filter design problems are investigated. The first problem is the design of TFBG filter for a specified bandwidth. The other is maximizing the bandwidth of the TFBG filter for a given grating length and maximum index modulation of the FBG. A more practical asymmetrical triangular FBG filter design is also considered. The results show that for the same grating length and maximum index modulation, a larger bandwidth can be achieved with a chirped grating. The maximized bandwidth design can be used to achieve the maximum possible bandwidth for the specified grating length, maximum index modulation and chirp rate. The results obtained using CMAES algorithm (codes available at http://www.ntu.edu.sg/home/epnsugan) is compared with the results of PSO and other algorithms. Comparisons show that the CMAES algorithm is more consistent in obtaining the best solution with reduced computation time. Hence, the CMAES algorithm is effective for the design of TFBG filters for sensor applications.

Baskar, S.; Suganthan, P. N.; Ngo, N. Q.; Alphones, A.; Zheng, R. T.

2006-04-01

187

Multi-scale mechanism based life prediction of polymer matrix composites for high temperature airframe applications  

NASA Astrophysics Data System (ADS)

A multi-scale mechanism-based life prediction model is developed for high-temperature polymer matrix composites (HTPMC) for high temperature airframe applications. In the first part of this dissertation the effect of Cloisite 20A (C20A) nano-clay compounding on the thermo-oxidative weight loss and the residual stresses due to thermal oxidation for a thermoset polymer bismaleimide (BMI) are investigated. A three-dimensional (3-D) micro-mechanics based finite element analysis (FEA) was conducted to investigate the residual stresses due to thermal oxidation using an in-house FEA code (NOVA-3D). In the second part of this dissertation, a novel numerical-experimental methodology is outlined to determine cohesive stress and damage evolution parameters for pristine as well as isothermally aged (in air) polymer matrix composites. A rate-dependent viscoelastic cohesive layer model was implemented in an in-house FEA code to simulate the delamination initiation and propagation in unidirectional polymer composites before and after aging. Double cantilever beam (DCB) experiments were conducted (at UT-Dallas) on both pristine and isothermally aged IM-7/BMI composite specimens to determine the model parameters. The J-Integral based approach was adapted to extract cohesive stresses near the crack tip. Once the damage parameters had been characterized, the test-bed FEA code employed a micromechanics based viscoelastic cohesive layer model to numerically simulate the DCB experiment. FEA simulation accurately captures the macro-scale behavior (load-displacement history) simultaneously with the micro-scale behavior (crack-growth history).

Upadhyaya, Priyank

188

UN Institute for Training and Research Operational Satellite Applications Programme  

NSDL National Science Digital Library

Satellites are used for just about any purpose imaginable, and the United Nations Institute for Training and Research Operational Satellite Applications Programme (UNITAR) is one that is meant to help out in "the life of communities exposed to poverty, hazards and risk." On their site, visitors should first take a look at the "What we do" area to learn about their recent achievements and work. Moving on, they can view their latest satellite maps of places such as Vietnam and Cambodia. The maps are entirely free, and they cover such topics as flood hazards, environmental degradation, and active fire locations. After a quick look, visitors can move on to read up on their satellite image services, technical assistance, and ordering information (for those who desire physical copies). The site also contains a glossary of terms, and a sign-in area for those users who wish to compile and maintain a record of the maps they will need to use most frequently.

189

Operational transfer path analysis: Theory, guidelines and tire noise application  

NASA Astrophysics Data System (ADS)

The operational transfer path analysis (OTPA) method is the subject of research in this article, which starts with a discussion on it's theory. Here clear similarities with the MIMO technique in experimental modal analysis are found. Based on the knowledge of MIMO, one finds that input signals are allowed to be coherent to a certain extend. As coherence can be larger in OTPA in practice, the method is extended with the singular value decomposition method to reduce influences of noise. The article proceeds with a discussion on points of attention, or boundary conditions, in practical applications. An analysis on tire noise is included to illustrate the points of attention and the methods strength in, for example, vehicle TPA on tires.

de Klerk, D.; Ossipov, A.

2010-10-01

190

An operational global ocean forecast system and its applications  

NASA Astrophysics Data System (ADS)

A global Real-Time Ocean Forecast System (RTOFS) was implemented in operations at NCEP/NWS/NOAA on 10/25/2011. This system is based on an eddy resolving 1/12 degree global HYCOM (HYbrid Coordinates Ocean Model) and is part of a larger national backbone capability of ocean modeling at NWS in strong partnership with US Navy. The forecast system is run once a day and produces a 6 day long forecast using the daily initialization fields produced at NAVOCEANO using NCODA (Navy Coupled Ocean Data Assimilation), a 3D multi-variate data assimilation methodology. As configured within RTOFS, HYCOM has a horizontal equatorial resolution of 0.08 degrees or ~9 km. The HYCOM grid is on a Mercator projection from 78.64 S to 47 N and north of this it employs an Arctic dipole patch where the poles are shifted over land to avoid a singularity at the North Pole. This gives a mid-latitude (polar) horizontal resolution of approximately 7 km (3.5 km). The coastline is fixed at 10 m isobath with open Bering Straits. This version employs 32 hybrid vertical coordinate surfaces with potential density referenced to 2000 m. Vertical coordinates can be isopycnals, often best for resolving deep water masses, levels of equal pressure (fixed depths), best for the well mixed unstratified upper ocean and sigma-levels (terrain-following), often the best choice in shallow water. The dynamic ocean model is coupled to a thermodynamic energy loan ice model and uses a non-slab mixed layer formulation. The forecast system is forced with 3-hourly momentum, radiation and precipitation fluxes from the operational Global Forecast System (GFS) fields. Results include global sea surface height and three dimensional fields of temperature, salinity, density and velocity fields used for validation and evaluation against available observations. Several downstream applications of this forecast system will also be discussed which include search and rescue operations at US Coast Guard, navigation safety information provided by OPC using real time ocean model guidance from Global RTOFS surface ocean currents, operational guidance on radionuclide dispersion near Fukushima using 3D tracers, boundary conditions for various operational coastal ocean forecast systems (COFS) run by NOS etc.

Mehra, A.; Tolman, H. L.; Rivin, I.; Rajan, B.; Spindler, T.; Garraffo, Z. D.; Kim, H.

2012-12-01

191

NOAA Operational Model Archive Distribution System (NOMADS): High Availability Applications for Reliable Real Time Access to Operational Model Data  

NASA Astrophysics Data System (ADS)

To reduce the impact of natural hazards and environmental changes, the National Centers for Environmental Prediction (NCEP) provide first alert and a preferred partner for environmental prediction services, and represents a critical national resource to operational and research communities affected by climate, weather and water. NOMADS is now delivering high availability services as part of NOAA’s official real time data dissemination at its Web Operations Center (WOC) server. The WOC is a web service used by organizational units in and outside NOAA, and acts as a data repository where public information can be posted to a secure and scalable content server. A goal is to foster collaborations among the research and education communities, value added retailers, and public access for science and development efforts aimed at advancing modeling and GEO-related tasks. The user (client) executes what is efficient to execute on the client and the server efficiently provides format independent access services. Client applications can execute on the server, if it is desired, but the same program can be executed on the client side with no loss of efficiency. In this way this paradigm lends itself to aggregation servers that act as servers of servers listing, searching catalogs of holdings, data mining, and updating information from the metadata descriptions that enable collections of data in disparate places to be simultaneously accessed, with results processed on servers and clients to produce a needed answer. The services used to access the operational model data output are the Open-source Project for a Network Data Access Protocol (OPeNDAP), implemented with the Grid Analysis and Display System (GrADS) Data Server (GDS), and applications for slicing, dicing and area sub-setting the large matrix of real time model data holdings. This approach insures an efficient use of computer resources because users transmit/receive only the data necessary for their tasks including metadata. Data sets served in this way with a high availability server offer vast possibilities for the creation of new products for value added retailers and the scientific community. We demonstrate how users can use NOMADS services to select the values of Ensemble model runs over the ith Ensemble component, (forecast) time, vertical levels, global horizontal location, and by variable, virtually a 6-Dimensional data cube of access across the internet. The example application called the “Ensemble Probability Tool” make probability predictions of user defined weather events that can be used in remote areas for weather vulnerable circumstances. An application to access data for a verification pilot study is shown in detail in a companion paper (U06) collaboration with the World Bank and is an example of high value, usability and relevance of NCEP products and service capability over a wide spectrum of user and partner needs.

Alpert, J. C.; Wang, J.

2009-12-01

192

Exokernel: an operating system architecture for application-level resource management  

Microsoft Academic Search

We describe an operating system architecture that securely multiplexes machine resources while permitting an unprecedented degree of application-specific customization of traditional operating system abstractions. By abstracting physical hardware resources, traditional operating systems have significantly limited the performance, flexibility, and functionality of applications. The exokernel architecture removes these limitations by allowing untrusted software to implement traditional operating system abstractions entirely at

Dawson R. Engler; M. Frans Kaashoek; James O'Toole Jr

1995-01-01

193

SVGA and XGA active matrix microdisplays for head-mounted applications  

NASA Astrophysics Data System (ADS)

The MicroDisplay Corporation's liquid crystal on silicon (LCOS) display devices are based on the union of several technologies with the extreme integration capability of conventionally fabricated CMOS substrates. The fast liquid crystal operation modes and new scalable high-performance pixel addressing architectures presented in this paper enable substantially improved color, contrast, and brightness while still satisfying the optical, packaging, and power requirements of portable applications. The entire suite of MicroDisplay's technologies was devised to create a line of mixed-signal application-specific integrated circuits (ASICs) in single-chip display systems. Mixed-signal circuits can integrate computing, memory, and communication circuitry on the same substrate as the display drivers and pixel array for a multifunctional complete system-on-a-chip. System-on-a-chip benefits also include reduced head supported weight requirements through the elimination of off-chip drive electronics.

Alvelda, Phillip; Bolotski, Michael; Brown, Imani L.

2000-03-01

194

The application of a job exposure matrix in the natural gas industry.  

PubMed

A questionnaire was designed, implemented, and analyzed, using a job exposure matrix format, to profile jobs in the Pipeline Division of a natural gas company with respect to possible hazardous exposures. The categories of chemical, physical, ergonomic, biological, and psychological hazards were surveyed. The first stage was to formulate and confirm a list of hazardous agents extant within the Pipeline Operations. This was done by making on-site observations and interviewing safety supervisors and workers, as well as by exploring the literature on the natural gas industry. The second stage of the project entailed the collection of data about whether a particular hazardous agent was present at a location, and if so, which workers were exposure to it, and at what intensity and frequency they were exposed. This assessment was made by groups identified as expert assessors, senior workers who were familiar with the processes and range of job titles at their locations. These experienced workers rated all job titles for workers at that site. The final stage of the project was to critically examine and validate the data collected. Three analyses were performed. The first was a comparison of the assessments with known outcomes of the medical surveillance testing that was completed in 1995. Secondly, the agreement between the assessments done by the expert assessor group, and a rating done by the jobholder, was examined. Finally, consideration was given to the sureness expressed by each of the rating groups about the analysis they had provided. PMID:14674800

Maher, Nora

2003-01-01

195

Java application for the superposition T-matrix code to study the optical properties of cosmic dust aggregates  

NASA Astrophysics Data System (ADS)

In this paper, we report the development of a java application for the Superposition T-matrix code, JaSTA (Java Superposition T-matrix App), to study the light scattering properties of aggregate structures. It has been developed using Netbeans 7.1.2, which is a java integrated development environment (IDE). The JaSTA uses double precession superposition codes for multi-sphere clusters in random orientation developed by Mackowski and Mischenko (1996). It consists of a graphical user interface (GUI) in the front hand and a database of related data in the back hand. Both the interactive GUI and database package directly enable a user to model by self-monitoring respective input parameters (namely, wavelength, complex refractive indices, grain size, etc.) to study the related optical properties of cosmic dust (namely, extinction, polarization, etc.) instantly, i.e., with zero computational time. This increases the efficiency of the user. The database of JaSTA is now created for a few sets of input parameters with a plan to create a large database in future. This application also has an option where users can compile and run the scattering code directly for aggregates in GUI environment. The JaSTA aims to provide convenient and quicker data analysis of the optical properties which can be used in different fields like planetary science, atmospheric science, nano science, etc. The current version of this software is developed for the Linux and Windows platform to study the light scattering properties of small aggregates which will be extended for larger aggregates using parallel codes in future. Catalogue identifier: AETB_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AETB_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 571570 No. of bytes in distributed program, including test data, etc.: 120226886 Distribution format: tar.gz Programming language: Java, Fortran95. Computer: Any Windows or Linux systems capable of hosting a java runtime environment, java3D and fortran95 compiler; Developed on 2.40 GHz Intel Core i3. Operating system: Any Windows or Linux systems capable of hosting a java runtime environment, java3D and fortran95 compiler. RAM: Ranging from a few Mbytes to several Gbytes, depending on the input parameters. Classification: 1.3. External routines: jfreechart-1.0.14 [1] (free plotting library for java), j3d-jre-1.5.2 [2] (3D visualization). Nature of problem: Optical properties of cosmic dust aggregates. Solution method: Java application based on Mackowski and Mischenko's Superposition T-Matrix code. Restrictions: The program is designed for single processor systems. Additional comments: The distribution file for this program is over 120 Mbytes and therefore is not delivered directly when Download or Email is requested. Instead a html file giving details of how the program can be obtained is sent. Running time: Ranging from few minutes to several hours, depending on the input parameters. References: [1] http://www.jfree.org/index.html [2] https://java3d.java.net/

Halder, P.; Chakraborty, A.; Deb Roy, P.; Das, H. S.

2014-09-01

196

Matrix elements in the coupled-cluster approach - With application to low-lying states in Li  

NASA Technical Reports Server (NTRS)

A procedure is suggested for evaluating matrix elements of an operator between wavefunctions in the coupled-cluster form. The use of the exponential ansatz leads to compact exponential expressions also for matrix elements. Algorithms are developed for summing all effects of one-particle clusters and certain chains of two-particle clusters (containing the well-known random-phase approximation as a subset). The treatment of one-particle perturbations in single valence states is investigated in detail. As examples the oscillator strength for the 2s-2p transition in Li as well as the hyperfine structure for the two states are studied and compared to earlier work.

Martensson-Pendrill, Ann-Marie; Ynnerman, Anders

1990-01-01

197

Applications of matrix derivatives to optimization problems in statistical pattern recognition  

NASA Technical Reports Server (NTRS)

A necessary condition for a real valued Frechet differentiable function of a vector variable have an extremum at a vector x sub 0 is that the Frechet derivative vanishes at x sub 0. A relationship between Frechet differentials and matrix derivatives was established that obtains a necessary condition on the matrix derivative at an extrema. These results are applied to various scalar functions of matrix variables which occur in statistical pattern recognition.

Morrell, J. S.

1975-01-01

198

Matrix effects for reflectivity spectra of dispersed nanophase (superparamagnetic) hematite with application to Martian spectral data  

Microsoft Academic Search

The effect of the matrix on the reflectivity spectra of nanophase (superparamagnetic) hematite (np-Hm) dispersed within the matrix was investigated in four series of powder samples containing np-Hm dispersed within discrete powder particles (of two size ranges) of silica gel and activated alumina. The spectral data show that matrix effects are large. Samples with the same Fe2O3 content can have

Richard V. Morris; Howard V. Lauer

1990-01-01

199

Operational Applications from the Suomi Npp and Jpss Satellites  

NASA Astrophysics Data System (ADS)

The Joint Polar Satellite System is NOAA's new operational satellite program and includes the SUOMI National Polar Partnership (NPP) as a bridge between NOAA's operational Polar Orbiting Environmental Satellite (POES) series, which began in 1978, and the first JPSS operational satellite scheduled for launch in 2017. JPSS provides critical data for key NOAA product and services, which the Nation depends on. These products and services include: Weather forecasting - data from the JPSS Cross-track Infrared Sounder (CrIS) and the Advanced Technology Microwave Sounder (ATMS) are needed to forecast weather events out to 7 days. Nearly 85% of all data used in weather forecasting are from polar orbiting satellites. Environmental monitoring - data from the JPSS Visible Infrared Imager Radiometer Suite (VIIRS) are used to monitor the environment including the health of coastal ecosystems, drought conditions, fire, smoke, dust, snow and ice, and the state of oceans, including sea surface temperature and ocean color. Climate monitoring - data from JPSS instruments, including OMPS, CERES and TSIS will provide continuity to climate data records established using NOAA POES and NASA Earth Observing System (EOS) satellite observations. These data records provide a unified and coherent long-term observation of the environment; the records and products are critical to climate modelers, scientists, and decision makers concerned with advancing climate change understanding, prediction, mitigation and adaptation strategies, and policies. Data collection - JPSS satellites continue the POES data collection instruments that relay in situ data and observations from remote transmitters. These instruments relay data from remote, unmanned stations including wind, temperature and salinity readings from ocean buoys, which allow for the monitoring of the ocean. These instruments are also used to track wildlife. Search and rescue - JPSS will continue the search and rescue instruments on POES that relay distress signals from aviators, mariners or land-based users in distress. This system assists in the rescue of hundreds on an annual basis. At the AGU conference, we will discuss in detail the operational applications of JPSS data and early demonstrations provided by SUOMI NPP. Examples will include improvements in weather forecasting, monitoring of coastal water quality (e.g. harmful algal blooms), marine resources, forest fires, volcanic eruptions and smoke/dust plumes, and monitoring of droughts, snow and ice cover. The quality of JPSS data for climate monitoring will also be discussed.

Goldberg, M.; Furgerson, J.; Sjoberg, W.; Weng, F.; Csiszar, I. A.; Kilcoyne, H.; Gleason, J. F.

2012-12-01

200

Direct electrochemistry of alcohol oxidase using multiwalled carbon nanotube as electroactive matrix for biosensor application.  

PubMed

Rapid detection of alcohol is important in clinical diagnosis and fermentation industry. An octameric alcohol oxidase (AOx) (Mr 675 kDa) from Pichia pastoris, immobilized on multiwalled carbon nanotubes-Nafion® (MWCNT-Nf) matrix and encapsulated with polyethylenimine (PEI) on gold electrode (AuE), showed a redox peak at 0.21V (vs. Ag/AgCl electrode at pH 7.5) for oxidation of alcohol. The electron transfer rate constant and surface coverage of the immobilized AOx were 1.69±0.15 s?¹ and 2.43×10?¹² mol cm?², respectively. Studies on response and kinetics of Au-MWCNT-Nf-AOx-PEI bioelectrodes for alcohol showed a linear response in the range of 8 ?M-42 ?M, response time of 55 s for steady state current, and detection limit of 5 ?M. The bioelectrode retains ~90% of the original response even after four weeks when stored in potassium phosphate buffer pH 7.5 at 4 °C. The fabricated bioelectrode was found to exclude interference caused by the common electroactive species such as ascorbic acid, uric acid, lactic acid, glucose and urea. The bioelectrode also showed reliable response characteristics in blood serum samples. The findings of the investigation have established the direct electrochemistry of the AOx protein and its potential biosensor application for quantitative detection of alcohol in blood serum. PMID:23000393

Das, Madhuri; Goswami, Pranab

2013-02-01

201

Development and Evaluation of Novel Metal Reinforced Ceramic Matrix Composites for High Temperature Applications  

NASA Astrophysics Data System (ADS)

For high temperature applications two novel ceramic-matrix composite (CMC) materials are manufactured, by embedding molybdenum (Mo) and Hastelloy X (HX) wire meshes in 7YSZ ceramic. The mechanical properties and oxidizing behaviour at 1050°C were investigated. The designs, fabrication, assessment of the mechanical strength, cyclic and isothermal oxidation of the CMCs are described in this thesis. After manufacturing meshes, NiCrA1Y bond coats and 7YSZ were applied via plasma spraying. Bonding strength in some CMC samples are improved by vacuum heat treating, then as-sprayed and heat treated CMCs are subjected to three-point bend and impact tests. Mo and HX wire mesh incorporation in 7YSZ increase the strength and the elongation to failure. In particular, Mo wire increases yield load of 7YSZ by at least 3 times and HX wire increases yield by 9 times. Mo/7YSZ CMC degrades and oxidizes after 330 hours at 1050°C tests, but HX/7YSZ shows higher oxidation resistance. The metallographic analysis shows NiCrA1Y bond coat cracks and delaminates from the wires during isothermal tests. Cyclic test, creating larger thermal stresses, worsens the damage. To increase the oxidation and mechanical properties of these composites, a more effective ceramic coating method is recommended. Overall, the advantages of HX/7YSZ composite suggest further testing and investigation.

Mohammadi, Teymoor

202

Algorithms and Application of Sparse Matrix Assembly and Equation Solvers for Aeroacoustics  

NASA Technical Reports Server (NTRS)

An algorithm for symmetric sparse equation solutions on an unstructured grid is described. Efficient, sequential sparse algorithms for degree-of-freedom reordering, supernodes, symbolic/numerical factorization, and forward backward solution phases are reviewed. Three sparse algorithms for the generation and assembly of symmetric systems of matrix equations are presented. The accuracy and numerical performance of the sequential version of the sparse algorithms are evaluated over the frequency range of interest in a three-dimensional aeroacoustics application. Results show that the solver solutions are accurate using a discretization of 12 points per wavelength. Results also show that the first assembly algorithm is impractical for high-frequency noise calculations. The second and third assembly algorithms have nearly equal performance at low values of source frequencies, but at higher values of source frequencies the third algorithm saves CPU time and RAM. The CPU time and the RAM required by the second and third assembly algorithms are two orders of magnitude smaller than that required by the sparse equation solver. A sequential version of these sparse algorithms can, therefore, be conveniently incorporated into a substructuring for domain decomposition formulation to achieve parallel computation, where different substructures are handles by different parallel processors.

Watson, W. R.; Nguyen, D. T.; Reddy, C. J.; Vatsa, V. N.; Tang, W. H.

2001-01-01

203

Estimation of Normalized Coherency Matrix through the SIRV Model. Application to High Resolution POLSAR Data  

NASA Astrophysics Data System (ADS)

In the context of non-Gaussian polarimetric clutter models, this paper presents an application of the recent advances in the field of Spherically Invariant Random Vectors (SIRV) modelling for coherency matrix estimation in heterogeneous clutter. The complete description of the POLSAR data set is achieved by estimating the span and the normalized coherency independently. The normalized coherency describes the polarimetric diversity, while the span indicates the total received power. The main advantages of the proposed Fixed Point estimator are that it does not require any "a priori" information about the probability density function of the texture (or span) and it can be directly applied on adaptive neighbourhoods. Interesting results are obtained when coupling this Fixed Point estimator with an adaptive spatial support based on the scalar span information. Based on the SIRV model, a new maximum likelihood distance measure is introduced for unsupervised POLSAR classification. The proposed method is tested with airborne POLSAR images provided by the RAMSES system. Results of entropy/alpha/anisotropy decomposition, followed by unsupervised classification, allow discussing the use of the normalized coherency and the span as two separate descriptors of POLSAR data sets.

Vasile, G.; Ovarlez, J.-P.; Pascal, F.; Gay, M.

2009-04-01

204

Application of fiber bridging models to fatigue crack growth in unidirectional titanium matrix composites  

NASA Technical Reports Server (NTRS)

Several fiber bridging models were reviewed and applied to study the matrix fatigue crack growth behavior in center notched (0)(sub 8) SCS-6/Ti-15-3 and (0)(sub 4) SCS-6/Ti-6Al-4V laminates. Observations revealed that fatigue damage consisted primarily of matrix cracks and fiber matrix interfacial failure in the (0)(sub 8) SCS-6/Ti-15-3 laminates. Fiber-matrix interface failure included fracture of the brittle reaction zone and cracking between the two carbon rich fiber coatings. Intact fibers in the wake of the matrix cracks reduce the stress intensity factor range. Thus, an applied stress intensity factor range is inappropriate to characterize matrix crack growth behavior. Fiber bridging models were used to determine the matrix stress intensity factor range in titanium metal matrix composites. In these models, the fibers in the wake of the crack are idealized as a closure pressure. An unknown constant frictional shear stress is assumed to act along the debond or slip length of the bridging fibers. The frictional shear stress was used as a curve fitting parameter to available data (crack growth data, crack opening displacement data, and debond length data). Large variations in the frictional shear stress required to fit the experimental data indicate that the fiber bridging models in their present form lack predictive capabilities. However, these models provide an efficient and relatively simple engineering method for conducting parametric studies of the matrix growth behavior based on constituent properties.

Bakuckas, J. G., Jr.; Johnson, W. S.

1992-01-01

205

Novel Vibration Damping of Ceramic Matrix Composite Turbine Blades Developed for RLV Applications  

NASA Technical Reports Server (NTRS)

The Reusable Launch Vehicle (RLV) represents the next generation of space transportation for the U.S. space program. The goal for this vehicle is to lower launch costs by an order of magnitude from $10,000/lb to $1,000/lb. Such a large cost reduction will require a highly efficient operation, which naturally will require highly efficient engines. The RS-2200 Linear Aerospike Engine is being considered as the main powerplant for the RLV. Strong, lightweight, temperature-resistant ceramic matrix composite (CMC) materials such as C/SiC are critical to the development of the RS-2200. Preliminary engine designs subject turbopump components to extremely high frequency dynamic excitation, and ceramic matrix composite materials are typically lightly damped, making them vulnerable to high-cycle fatigue. The combination of low damping and high-frequency excitation creates the need for enhanced damping. Thus, the goal of this project has been to develop well-damped C/SiC turbine components for use in the RLV. Foster-Miller and Boeing Rocketdyne have been using an innovative, low-cost process to develop light, strong, highly damped turbopump components for the RS-2200 under NASA s Small Business Innovation Research (SBIR) program. The NASA Glenn Research Center at Lewis Field is managing this work. The process combines three-dimensionally braided fiber reinforcement with a pre-ceramic polymer. The three-dimensional reinforcement significantly improves the structure over conventional two-dimensional laminates, including high through-the-thickness strength and stiffness. Phase I of the project successfully applied the Foster-Miller pre-ceramic polymer infiltration and pyrolysis (PIP) process to the manufacture of dynamic specimens representative of engine components. An important aspect of the program has been the development of the manufacturing process. Results show that the three-dimensionally braided carbon-fiber reinforcement provides good processability and good mechanical stiffness and strength in comparison to materials produced with competing processes as shown in the graphs.

Min, James B.

2000-01-01

206

Particulate Titanium Matrix Composites Tested--Show Promise for Space Propulsion Applications  

NASA Technical Reports Server (NTRS)

Uniformly distributed particle-strengthened titanium matrix composites (TMCs) can be manufactured at lower cost than many types of continuous-fiber composites. The innovative manufacturing technology combines cold and hot isostatic pressing procedures to produce near-final-shape components. Material stiffness is increased up to 26-percent greater than that of components made with conventional titanium materials at no significant increase in the weight. The improved mechanical performance and low-cost manufacturing capability motivated an independent review to assess the improved properties of ceramic titanium carbide (TiC) particulate-reinforced titanium at elevated temperature. Researchers at the NASA Glenn Research Center creatively designed and executed deformation and durability tests to reveal operating regimes where these materials could lower the cost and weight of space propulsion systems. The program compares the elevated-temperature performance of titanium alloy Ti-6Al-4V matrix material to an alloy containing 10 wt% of TiC particles. Initial experiments showed that at these relatively low particle concentrations the material stiffness of the TMC was improved 20 percent over that of the plain Ti-6Al-4V alloy when tested at 427 C. The proportional limit and ultimate strength of the composite in tension are 21- and 14-percent greater than those of the plain alloy. Compression tests showed that the proportional limit is about 30 percent greater for TMC than for the plain alloy. The enhanced deformation resistance of the TMC was also evident in a series of tensile and compressive stress relaxation tests that were made. Specimens were subjected to tensile or compressive strain amplitudes of 0.75 percent for 24 hr followed by a return to zero strain imposed for 24 hr. The stress relaxation data were normalized with respect to the maximum stress for each case and plotted as a function of time in the following graph. Tensile stresses relaxed 19 percent for the TMC and 25 percent for the plain Ti-6Al-4V alloy. Compressive stresses relaxed 25 percent for the TMC and 39 percent for the plain Ti-6Al-4V alloy. The superior deformation resistance of the TMC extends to a creep rate that is 28-percent slower for the TMC when it is loaded to stress levels that are 26-percent higher than for the plain Ti-6Al-4V alloy.

Lerch, Bradley A.; Ellis, J. Rodney; Arnold. Steven M.

2004-01-01

207

Theory and computation of the matrix elements of the full interaction of the electromagnetic field with an atomic state: Application to the Rydberg and the continuous spectrum  

NASA Astrophysics Data System (ADS)

We develop practical formulas for the calculation of the matrix elements of the interaction of the electromagnetic field with an atomic state, beyond the long-wavelength approximation. The atom-plus-field Hamiltonian is chosen to have the multipolar form, containing the electric, paramagnetic, and diamagnetic operators. The final workable expressions include the interactions to all orders and are derived by first expanding the fields in partial waves. The electric-field operator reaches a constant value as the radial variable becomes large, contrary to the result of the electric-dipole approximation (EDA) where the value of the corresponding operator increases indefinitely. Applications are given for Rydberg states of hydrogen up to n=50 and for free-free transitions in a Coulomb potential. Such matrix elements are relevant to a number of real and virtual processes occurring during laser-atom interactions. The computation is done numerically, using a combination of analytic with numerical techniques. By comparing the results of the EDA with those of the exact treatment, it is shown that the former is inadequate in such cases. This finding has repercussions on the theory and understanding of the physics of quantum systems in high-lying Rydberg levels and wave packets or in scattering states.

Komninos, Yannis; Mercouris, Theodoros; Nicolaides, Cleanthes A.

2002-04-01

208

Rotary wing UAV potential applications: an analytical study through a matrix method  

Microsoft Academic Search

Industrial designers often need decision-making methods to develop innovative solutions combining specified customer's requirements with project technical constraints. This paper describes a matrix approach as a technique to support system designer since the early stages of development, when many and important decisions must be taken. In this work, the matrix method has been used to analyze the civil unmanned aerial

G. M. Saggiani; B. Teodorani

2004-01-01

209

Application of nanobiotechnology to construct a piezoelectric sensor matrix sensing the flexibility of immunoglobulin  

Microsoft Academic Search

We have constructed a piezoelectric sensor matrix with the capability of measuring the flexibility of immunoglobulin. The matrix consisted of 6 independent quartz crystal microbalance (QCM) coated with gold nanoparticles (GNP) of 3.5, 5, 12, 17, and 37 nm, and BSA. The detection was performed simultaneously. Antiserum against GNP bound to QCMs coated with 3.5 nm GNP and maximized for

G. Steven Huang; Yu-Shiun Chen; Xin-Yau Lin

2007-01-01

210

Application of the Finite-Element Z-Matrix Method to e-H2 Collisions  

NASA Technical Reports Server (NTRS)

The present study adapts the Z-matrix formulation using a mixed basis of finite elements and Gaussians. This is a energy-independent basis which allows flexible boundary conditions and is amenable to efficient algorithms for evaluating the necessary matrix elements with molecular targets.

Huo, Winifred M.; Brown, David; Langhoff, Stephen R. (Technical Monitor)

1997-01-01

211

Potential Applications of Matrix Organization Theory for the New Jersey Department of Education. Position Paper.  

ERIC Educational Resources Information Center

Matrix organization focuses on the shift from cost center or process input planning to product output or results planning. Matrix organization puts the personnel and the resources where they are needed to get the job done. This management efficiency is brought about by dividing all organizational activities into two areas: (1) input or maintenance…

Hanson, J. Robert

212

A Comparison of Item Sampling Plans in the Application of Multiple Matrix Sampling.  

ERIC Educational Resources Information Center

A Monte Carlo study, which simulated 10,000 examinees' responses to four tests, investigated the effect of item stratification on parameter estimation in multiple matrix sampling of achievement data. Practical multiple matrix sampling is based on item stratification by item discrimination and a sampling plan with moderate number of subtests. (SLD)

Gressard, Risa P.; Loyd, Brenda H.

1991-01-01

213

On friction layer formation in polymer matrix composite materials for brake applications  

Microsoft Academic Search

Due to the complexity of friction phenomena in polymer matrix composites, the friction mechanisms have not been fully understood. This paper concentrates on the characterization of friction layer formation and correlation of friction layer properties to the performance of a recently developed family of polymer matrix composites. It was demonstrated that character of the friction layer determines the friction performance

Peter Filip; Zdenek Weiss; David Rafaja

2002-01-01

214

A scalable, parallel matrix-free Stokes solver for geodynamic applications  

NASA Astrophysics Data System (ADS)

Here I describe a numerical method suitable for studying non-linear, large deformation processes in crustal and lithopspheric dynamics. The method utilizes a hybrid spatial discretisation which consists of mixed finite elements for the Stokes flow problem, coupled to a Lagrangian marker based discretisation to represent the material properties (viscosity and density). This approach is akin to the classical Marker-And-Cell (MAC) scheme of Harlow and the subsequently developed Material Point Method (MPM) of Sulsky and co-workers. The geometric flexibility and ease of modelling large deformation processes afforded by such mesh-particle methods has been exploited by the lithospheric dynamics community over the last 20 years. The strength of the Stokes preconditioner fundamentally controls the scientific throughput achievable and represents the largest bottleneck in the development of our understanding of geodynamic processes. The possibility to develop a 'cheap' and efficient preconditioning methodology which is suitable for the mixed Q2-P1 element is explored here. I describe a flexible strategy, which aims to address the Stokes preconditioning issue using an upper block triangular preconditioner, together with a geometric multi-grid preconditioner for the viscous block. The key to the approach is to utilize algorithms and data-structures that exploit current multi-core hardware and avoid the need for excessive global reductions. In order to develop a scalable method, special consideration is given to; the definition of the coarse grid operator, the smoother and the coarse grid solver. The performance characteristics of this hybrid matrix-free / partially assembled multi-level preconditioning strategy is examined. The robustness of the preconditioner with respect to the viscosity contrast and the topology of the viscosity field, together with the parallel scalability is demonstrated.

May, D.

2013-12-01

215

Advances in Ceramic Matrix Composite Blade Damping Characteristics for Aerospace Turbomachinery Applications  

NASA Technical Reports Server (NTRS)

For advanced aerospace propulsion systems, development of ceramic matrix composite integrally-bladed turbine disk technology is attractive for a number of reasons. The high strength-to-weight ratio of ceramic composites helps to reduce engine weight and the one-piece construction of a blisk will result in fewer parts count, which should translate into reduced operational costs. One shortcoming with blisk construction, however, is that blisks may be prone to high cycle fatigue due to their structural response to high vibration environments. Use of ceramic composites is expected to provide some internal damping to reduce the vibratory stresses encountered due to unsteady flow loads through the bladed turbine regions. A goal of our research was to characterize the vibration viscous damping behavior of C/SiC composites. The vibration damping properties were measured and calculated. Damping appeared to decrease with an increase in the natural frequency. While the critical damping amount of approximately 2% is required for typical aerospace turbomachinery engines, the C/SiC damping at high frequencies was less than 0.2% from our study. The advanced high-performance aerospace propulsion systems almost certainly will require even more damping than what current vehicles require. A purpose of this paper is to review some work on C/SiC vibration damping by the authors for the NASA CMC turbine blisk development program and address an importance of the further investigation of the blade vibration damping characteristics on candidate CMC materials for the NASA s advanced aerospace turbomachinery engine systems.

Min, James B.; Harris, Donald L.; Ting, J. M.

2011-01-01

216

Wavelet crosstalk matrix and its application to assessment of shift-variant imaging systems  

SciTech Connect

The objective assessment of image quality is essential for design of imaging systems. Barrett and Gifford [1] introduced the Fourier cross talk matrix. Because it is diagonal for continuous linear shift-invariant imaging systems, the Fourier cross talk matrix is a powerful technique for discrete imaging systems that are close to shift invariant. However, for a system that is intrinsically shift variant, Fourier techniques are not particularly effective. Because Fourier bases have no localization property, the shift-variance of the imaging system cannot be shown by the response of individual Fourier bases; rather, it is shown in the correlation between the Fourier coefficients. This makes the analysis and optimization quite difficult. In this paper, we introduce a wavelet cross talk matrix based on wavelet series expansions. The wavelet cross talk matrix allows simultaneous study of the imaging system in both the frequency and spatial domains. Hence it is well suited for shift variant systems. We compared the wavelet cross talk matrix with the Fourier cross talk matrix for several simulated imaging systems, namely the interior and exterior tomography problems, limited angle tomography, and a rectangular geometry positron emission tomograph. The results demonstrate the advantages of the wavelet cross talk matrix in analyzing shift-variant imaging systems.

Qi, Jinyi; Huesman, Ronald H.

2002-11-01

217

Universal elements for non-linear operators and their applications  

NASA Astrophysics Data System (ADS)

We prove that under certain topological conditions on the set of universal elements of a continuous map T acting on a topological space X, that the direct sum T[circle plus operator]Mg is universal, where Mg is multiplication by a generating element of a compact topological group. We use this result to characterize -supercyclic operators and to show that whenever T is a supercyclic operator and z1,...,zn are pairwise different non-zero complex numbers, then the operator z1T[circle plus operator]...[circle plus operator]znT is cyclic. The latter answers affirmatively a question of Bayart and Matheron.

Shkarin, Stanislav

2008-12-01

218

Application of the adjacency matrix eigenvectors method to geometry determination of toroidal carbon molecules  

NASA Astrophysics Data System (ADS)

Torusenes are defined as closed toroidal networks where every vertex or atom is 3-valent, and they can represent pure carbon tori. Here we study the geometries of two classes: hexagonal torusenes containing purely polyhex networks and the second class, 5,6,7-ring torusenes which besides hexagons contain also an equal number of 5- and 7-membered rings. As sophisticated quantum-mechanical methods for geometry determination are time consuming for large carbon cages, and having in mind the huge number of their isomers, one is interested in methods which are simple to apply but which are still able to produce plausible geometries. One of them is offered by the adjacency matrix elgenvectors (AME) method, which was proposed in this journal [D. E. Manolopoulos and P. W. Fowler, J. Chem. Phys. 96, 7603 (1992)]. The application of the AME method to fullerenes is based on an appropriately chosen triplet of eigenvectors. A rational choice may be made on the basis of their nodal properties. No rules have been formulated up to now on how to apply the AME method to torusenes. In order to find such a rule a systematic study of nodal properties of torusenes is crucial, and such a study is the subject of this paper. Theoretical and computer experimental considerations presented here suggest that a triplet a2,a3,aopt fulfills the task where the aopt should be checked for among those eigenvectors which possess no radial nodal plane but have one axial cut. In the present paper these findings have been elaborated for 5,6,7-ring torusenes with up to 270 atoms, and computer experiments have shown that similar findings hold for purely polyhex torusenes with up to 224 carbon atoms as well. In order to understand better these nodal properties, a quantum-mechanical study of free electrons on the surface of a torus was also undertaken.

Graovac, Ante; Plavši?, Dejan; Kaufman, Matjaž; Pisanski, Tomaž; Kirby, Edward C.

2000-08-01

219

SPIN: an extensible microkernel for application-specific operating system services  

Microsoft Academic Search

Application domains such as multimedia, databases, and parallel computing, require operating system services with high performance and high functionality. Existing operating systems provide fixed interfaces and implementations to system services and resources. This makes them inappropriate for applications whose resource demands and usage patterns are poorly matched by the services provided. The SPIN operating system enables system services to be

Brian N. Bershad; Craig Chambers; Susan J. Eggers; Chris Maeda; Dylan McNamee; Przemyslaw Pardyak; Stefan Savage; Emin Gün Sirer

1994-01-01

220

SPIN —an extensible microkernel for application-specific operating system services  

Microsoft Academic Search

Application domains such as multimedia, databases, and parallel computing, require operating system services with high performance and high functionality. Existing operating systems provide fixed interfaces and implementations to system services and resources. This makes them inappropriate for applications whose resource demands and usage patterns are poorly matched by the services provided. The SPIN operating system enables system services to be

Brian N. Bershad; Craig Chambers; Susan J. Eggers; Chris Maeda; Dylan McNamee; Przemys?aw Pardyak; Stefan Savage; Emin Gün Sirer

1995-01-01

221

Concept of Operations for Road Weather Connected Vehicle Applications.  

National Technical Information Service (NTIS)

Weather has a significant impact on the operations of the nations roadway system year round. These weather events translate into changes in traffic conditions, roadway safety, travel reliability, operational effectiveness, and productivity. It is, therefo...

C. J. Hill

2013-01-01

222

On an Algebraic Identity with Applications to Operator Theory.  

National Technical Information Service (NTIS)

In the report on an investigation of the Friedrichs equation in operator theory, certain algebraic relations, connecting the Friedrichs intertwining operators and perturbation determinants, are presented together with some generalizations. These relations...

J. H. Halton J. D. Pincus

1972-01-01

223

Developing scandium and zirconium containing aluminum boron carbide metal matrix composites for high temperature applications  

NASA Astrophysics Data System (ADS)

The study presented in this thesis focuses on developing castable, precipitation-strengthened Al--B4C metal matrix composites (MMCs) for high temperature applications. In the first part, B4C plates were immersed in liquid aluminum alloyed with Sc, Zr and Ti to investigate the interfacial reactions between B4C and liquid aluminum The influences of Sc, Zr and Ti on the interfacial microstructure in terms of individual and combined additions were examined. Results reveal that all three elements reacted with B4C and formed interfacial layers that acted as a diffusion barrier to limit the decomposition of B4C in liquid aluminum. The interfacial reactions and the reaction products in each system were identified. With the combined addition of Sc, Zr and Ti, most of the Ti was found to enrich at the interface, which not only offered appropriate protection of the B4C but also reduced the consumption of Sc and Zr at the interface. In the second part, Sc and Zr were introduced into Al-15vol.% B 4C composites presaturated by Ti, and eight experimental composites with different Sc and Zr levels were prepared via a conventional casting technique. It was found that Sc was involved in the interfacial reactions with B 4C that partially consume Sc. The Sc addition yielded considerable precipitation strengthening in the as-cast and peak aged conditions. To achieve an equivalent strengthening effect of Sc in binary Al-Sc alloys, approximately double the amount of Sc is required in Al-B4C composites. On the contrary, no major Zr reaction products were found at the interfaces and the major part of Zr remained in the matrix for the precipitation strengthening. The combination of Sc and Zr enhanced sthe precipitation strengthening. Two kinds of nanoscale precipitates, Al3Sc and Al3(Sc, Zr), were found in the as-cast microstructure and contributed to the increase in the matrix hardness. In the third part, all the experimental composites were isothermally aged at 300, 350, 400 and 450°C after a homogenization/solution treatment. Results demonstrate that the addition of Sc generated a considerable precipitation hardening of the matrix of the composites for all aging temperatures applied. The precipitation hardening effect increased when increasing the Sc content and decreased with increase in aging temperature. The combination of alloying Sc and Zr in Al-B4C composites produced a remarkable synergistic effect. The addition of Zr provided not only a strength increase at peak aging but also an improvement of thermal stability. The composites with a high Zr:Sc ratio (?1) showed excellent thermal stability of the strength up to 400°C. The overaging in these materials was delayed by ˜100°C compared with the Zr-free composites at the same Sc level. The precipitate volume fraction, the average radius and the size distribution of nanoscale Al3Sc and Al3(Sc,Zr) precipitates during the aging process were measured. The Al3(Sc,Zr) precipitates generally showed a much better coarsening resistance than the Al3Sc precipitates. In the fourth part, two experimental composites with 0.4wt.% Sc and 0.4wt.% Sc plus 0.24wt.% Zr 0were selected to examine the mechanical properties during long-term exposure (2000h) at elevated temperatures from 250 to 350°C. For long-term thermal stability, the mechanical properties of the Sc and Zr containing composite were stable up to 300°C, while the composite containing only Sc exhibited a good softening resistance up to 250°C. At higher temperatures the strengths of both composites decreased with prolonged annealing time. The reduction of the composites' mechanical properties during long-time annealing at higher temperatures was dominated by the precipitate coarsening. Finally, two experimental composites with 0.58wt.% Sc and 0.58wt.% Sc plus 0.24wt.% Zr, were respectively hot-rolled to a 2 mm thick sheet with a total reduction of 93%. Results indicate that the Sc- and Zr-containing composites possessed a good hot rolling processability. (Abstract shortened by UMI.)

Lai, Jing

224

Advanced Composites: Mechanical Properties and Hardware Programs for Selected Resin Matrix Materials. [considering space shuttle applications  

NASA Technical Reports Server (NTRS)

This design note presents typical mechanical properties tabulated from industrial and governmental agencies' test programs. All data are correlated to specific products and all of the best known products are presented. The data include six epoxies, eight polyimides and one polyquinoxaline matrix material. Bron and graphite are the fiber reinforcements. Included are forty-two summaries of advanced (resin matrix) composite programs in existence in the United States. It is concluded that the selection of appropriate matrices, the geometric manner in which the fibers are incorporated in the matrix and the durability of the bond between fiber and matrix establish the end properties of the composite material and the performance of the fabricated structure.

Welhart, E. K.

1976-01-01

225

Energy levels and transition probability matrix elements of ruby for maser applications  

NASA Technical Reports Server (NTRS)

Program computes fine structure energy levels of ruby as a function of magnetic field. Included in program is matrix formulation, each row of which contains a magnetic field and four corresponding energy levels.

Berwin, R. W.

1971-01-01

226

Carbon Fiber Reinforced Glass Matrix Composites for Structural Space Based Applications.  

National Technical Information Service (NTIS)

A variety of ultra-high elastic modulus pitch-based carbon fibers were combined with several different glass and glass-ceramic matrix compositions to produce unidirectionally reinforced composites. Composite performance was evaluated in several different ...

K. M. Prewo W. K. Tredway

1989-01-01

227

Application of Matrix Correction Methods on a Plate and a Truss Structure.  

National Technical Information Service (NTIS)

Matrix correction methods proposed by Chen, Baruch, Berman, and Ceasar are evaluated using a simple plate and a truss structure. The plate experimental data is obtained from an impact test. The truss structure data is simulated. The structures are modeled...

A. Deboer H. H. Ottens B. W. Kooi J. J. Wijker

1988-01-01

228

Matrix effects for reflectivity spectra of dispersed nanophase (superparamagnetic) hematite with application to Martian spectral data  

NASA Astrophysics Data System (ADS)

The effect of the matrix on the reflectivity spectra of nanophase (superparamagnetic) hematite (np-Hm) dispersed within the matrix was investigated in four series of powder samples containing np-Hm dispersed within discrete powder particles (of two size ranges) of silica gel and activated alumina. The spectral data show that matrix effects are large. Samples with the same Fe2O3 content can have np-Hm absorption edges characterized by very different positions and curvature and slope indices, while samples with equivalent absorption edges can have very different Fe2O3 concentrations. Thus, quantitative relationships between the positions of ferric absorption edges and Fe2O3 concentrations are unreliable without knowledge of matrix properties of the system. It is shown that it was possible to match the Fe2O3 concentration, magnetic properties, and spectral data for Martian surface material with a laboratory mixture whose only ferric-bearing phase was hematite.

Morris, R. V.; Lauer, H. V.

1990-04-01

229

Flight Dynamics Application of a New Symbolic Matrix Order-Reduction Algorithm  

Microsoft Academic Search

In the field of control, the basis of state-space theory is the representation of a system in a matrix-like form and its subsequent manipulation for synthesis and analysis. The state-space model represents any system, given by nonlinear first-order ordinary differential equations (ODE), as a 2 2 block matrix _ x y = A B C D x u using state

Andrés Marcos; Declan G. Bates; Ian Postlethwaite

230

Application of a fiber-matrix model to transport in renal tubules  

Microsoft Academic Search

The effects of tight junction structure on water and solute fluxes across proximal tubular epithelium were examined with fiber-matrix equations previously derived by Curry and Michel (1980. Microvascular Research. 20:96-99). Using plausible estimates of tight junction fiber length and width the model pre- dicts solute (Ps) and water permeability (Lp) coefficients that agree with the mea- sured values. When fiber-matrix

W. D. Fraser; A. D. BAINES

1989-01-01

231

Transglutaminase 2 cross-linking of matrix proteins: biological significance and medical applications  

Microsoft Academic Search

This review summarises the functions of the enzyme tissue transglutaminase (TG2) in the extracellular matrix (ECM) both as\\u000a a matrix stabiliser through its protein cross-linking activity and as an important cell adhesion protein involved in cell\\u000a survival. The contribution of extracellular TG2 to the pathology of important diseases such as cancer and fibrosis are discussed\\u000a with a view to the

R. J. Collighan; M. Griffin

2009-01-01

232

The Iron Project and the RmaX Project: R-Matrix Data for Astrophysical and Fusion Applications  

Microsoft Academic Search

The R-Matrix method has long been employed to compute fundamental atomic parameters with high precision for large scale applications to astrophysical sources and magnetic and intertial fusion devices. Ongoing work is part of two projects: The Iron Project that focuses on Fe-peak elements, and the RmaX Project aimed at spectral diagnostics of laboratory and astrophysical X-ray plasmas. The primary atomic

Anil K. Pradhan; Anil K

2005-01-01

233

78 FR 40519 - Cooper Nuclear Station; Application and Amendment to Facility Operating License Involving...  

Federal Register 2010, 2011, 2012, 2013

...REGULATORY COMMISSION [Docket No. 50-298; NRC-2013-0139] Cooper Nuclear Station; Application and Amendment to Facility Operating...Public Power District (the licensee), for operation of the Cooper Nuclear Station (CNS) located in Nemaha County,...

2013-07-05

234

Operational Testing and Applications of the AIRS FPA with Infrared Fisheye Optics.  

National Technical Information Service (NTIS)

Nova's development of the Modular Infrared Imaging Applications Development System (MIRIADS) produced a longwave infrared (LWIR) camera system that operated the Adaptive Infrared Sensor (AIRS) focal plane device produced by the Raytheon Infrared Operation...

C. R. Baxter M. A. Massie T. J. Bartolac

2002-01-01

235

14 CFR 93.219 - Allocation of slots for essential air service operations and applicable limitations.  

Code of Federal Regulations, 2011 CFR

...2014-01-01 false Allocation of slots for essential air service operations and applicable limitations...DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES Allocation of Commuter and...

2014-01-01

236

A computational method for solving stochastic Itô-Volterra integral equations based on stochastic operational matrix for generalized hat basis functions  

NASA Astrophysics Data System (ADS)

In this paper, a new computational method based on the generalized hat basis functions is proposed for solving stochastic Itô-Volterra integral equations. In this way, a new stochastic operational matrix for generalized hat functions on the finite interval [0,T] is obtained. By using these basis functions and their stochastic operational matrix, such problems can be transformed into linear lower triangular systems of algebraic equations which can be directly solved by forward substitution. Also, the rate of convergence of the proposed method is considered and it has been shown that it is O(1/n2). Further, in order to show the accuracy and reliability of the proposed method, the new approach is compared with the block pulse functions method by some examples. The obtained results reveal that the proposed method is more accurate and efficient in comparison with the block pule functions method.

Heydari, M. H.; Hooshmandasl, M. R.; Maalek Ghaini, F. M.; Cattani, C.

2014-08-01

237

10 CFR 50.34 - Contents of construction permit and operating license applications; technical information.  

Code of Federal Regulations, 2010 CFR

...design criteria for water-cooled nuclear power plants similar in design and...Applications for light water cooled nuclear power plant operating licenses...Applications for light-water-cooled nuclear power plant construction...

2009-01-01

238

Interdisciplinary matrix in economics: two applications to the transition from socialism to capitalism.  

PubMed

The 7-fold interdisciplinary matrix is introduced. This integrated methodological point of view is original, although it is based on ideas of others in various ways. The name for this new approach draws on the Kuhnian notion of a disciplinary matrix. There are four components of the Kuhnian matrix on which the existence of scientific communities hinges: symbolic generalizations, models, values, and exemplars. In this context the term "paradigm" should refer to exemplars. The interdisciplinary matrix is composed of seven elements: cybernetics, catastrophe theory, fractal geometry, deterministic chaos, artificial intelligence, theory of complexity, and humanistic values. Scientific developments have recently brought substantial changes in the structure of scientific communities. Transferability of ideas and thoughts contributed to the creation of scientific communities, which unite representatives of various professions. When researching into certain phenomena we no longer need to develop theories for them from scratch, as we can draw on the achievements in other disciplines. Two examples of the employment of the interdisciplinary matrix in macroeconomics are elaborated here: the investment cycle model in socialist economy, and the model of economic transformation based on chaotic hysteresis. PMID:19781137

Jakimowicz, Aleksander

2009-10-01

239

Modified Laguerre operational matrices for fractional calculus and applications  

Microsoft Academic Search

The modified Laguerre polynomial is defined with an additional parameter from the conventional one and is applied to approach the problems of fractional calculus. First, the operational matrices for the integration and the differentiation of the modified Laguerre polynomials are derived. The generalized operational matrices corresponding to s, 1\\/s, s\\/(s2 + 1) exp [ ? s\\/(s + 1)] are derived

RONG-YEU CHANG; KUN-CHOU CHEN; MAW-LING WANG

1985-01-01

240

GIS applications for military operations in coastal zones  

Microsoft Academic Search

In order to successfully support current and future US military operations in coastal zones, geospatial information must be rapidly integrated and analyzed to meet ongoing force structure evolution and new mission directives. Coastal zones in a military-operational environment are complex regions that include sea, land and air features that demand high-volume databases of extreme detail within relatively narrow geographic corridors.

S. Fleming; T. Jordan; M. Madden; E. L. Usery; R. Welch

2009-01-01

241

SAR Needs and Requirements for Operational Ocean Management Applications  

Microsoft Academic Search

Government agencies involved in operational ocean management activities such as fisheries enforcement, marine sanctuary management, and hazard response are beginning to use synthetic aperture radar (SAR) data and derived products in carrying out their operational mission. SAR-derived environmental measurements of interest include: coastal winds, wave parameters, ice parameters, oil spill location, vessel positions, and near- shore bathymetry. These measurements are

W. G. Pichel; F. Monaldo; C. Wackerman; P. Clemente-Colón; X. Li; K. Friedman

242

Preparing the CAA Title V operating permit application  

SciTech Connect

The CAA amendments contain 11 new and amended titles, including enhanced non-attainment area provisions, additional conditions for controlling hazardous air pollutants, expanded monitoring and record keeping requirements, and increased enforcement authority. The cornerstone of the regulation is the operating permits program (Title V). In the past, permits have been issued to construct or modify sources, and some sources have been permitted in states with operating permit programs. Such programs will remain in effect. However, under the new CAA, most emissions sources will be required to have an operating permit. Title V's permit provision initially affects about 34,000 major facilities and may affect another 350,000 smaller sources in the future. The amendments also increase the number of regulated pollutants from 21 to about 200. Operating permits limit emissions from manufacturing operations, and place further restrictions on raw materials and products.

Wyles, T.R. (Trinity Consultants Inc., Atlanta, GA (United States))

1994-01-01

243

RoboCon: Operator interface for robotic applications  

SciTech Connect

Carnegie Mellon U. and ORNL`s Robotics and Process Systems Division are developing a state-of-the-art robot operator control station (RoboCon) with standardized hardware and software control interfaces to be adaptable to a variety of remote and robotic equipment currently funded by DOE`s Office of Science & Technology Robotics Technology Development Program. The human operation and telerobotic and supervisory control of sophisticated and remote and robotic systems is a complex, tiring, and non-intuitive activity. Since decontamination & decommissioning, selective equipment removal, mixed waste operations, and in-tank cleanup are going to be a major future activity in DOE environmental restoration and waste management cleanup agenda, it seems necessary to utilize an operator control station and interface which maximizes operator comfort and productivity.

Schempf, H.; Warwick, J.; Fung, M.; Chemel, B.; Blackwell, M.

1996-12-31

244

The matrix coalescent and an application to human single-nucleotide polymorphisms.  

PubMed Central

The "matrix coalescent" is a reformulation of the familiar coalescent process of population genetics. It ignores the topology of the gene tree and treats the coalescent as a Markov process describing the decay in the number of ancestors of a sample of genes as one proceeds backward in time. The matrix formulation of this process is convenient when the population changes in size, because such changes affect only the eigenvalues of the transition matrix, not the eigenvectors. The model is used here to calculate the expectation of the site frequency spectrum under various assumptions about population history. To illustrate how this method can be used with data, we then use it in conjunction with a set of SNPs to test hypotheses about the history of human population size.

Wooding, Stephen; Rogers, Alan

2002-01-01

245

Design of a security screening system with a capacitance sensor matrix operating in single-electrode mode  

Microsoft Academic Search

A planar capacitance sensor matrix may be used to detect dangerous objects for security screening because different materials under test (MUT) have different permittivities. Usually, each capacitance sensing element consists of two electrodes, one for excitation and the other for detection. A weakness of such a two-electrode structure is that its sensing depth is limited. To increase the sensing depth,

Dixiang Chen; Xiaohui Hu; Wuqiang Yang

2011-01-01

246

Department of Defense operational applications of wind measurements  

NASA Technical Reports Server (NTRS)

A stated objective for this symposium is to identify requirements for global wind measurements. This paper will draw from recent reports which considered the impact of over 100 environmental factors known to affect military operations. A conclusion that can be drawn from those analyses is that one environmental factor, atmospheric wind, has an operational impact on each of the 48 mission areas examined. This paper will characterize the impact of wind on the various mission areas and will define and summarize both 'technical' and 'operational' requirements for wind intelligence.

Ramsay, Allan C.

1985-01-01

247

Applicability of Visual Analytics to Defence and Security Operations.  

National Technical Information Service (NTIS)

In the context of modern defence and security operations, analysts are faced with a continuously growing set of information of different nature which causes significant information overload problems and prevent developing good situation awareness. Fortuna...

D. Gouin V. Lavigne

2011-01-01

248

T-Matrix Method and its Applications to Electromagnetic Scattering by Particles: A Current Perspective  

NASA Technical Reports Server (NTRS)

This note serves as a short introduction to the reprint of our article "T-matrix computations of light scattering by nonspherical particles: a review" (JQSRT 1996; 55:535:75). We first discuss the motivation for writing that article and explain its historical context. This is followed by a short overview of more recent developments.

Mishchenko, Michael I.; Travis, Larry D.; Mackowski, Daniel W.

2010-01-01

249

Pseudospectra and stability radii for analytic matrix functions with application to time-delay systems  

Microsoft Academic Search

Definitions for pseudospectra and stability radii of an analytic matrix function are given, where the structure of the function is exploited. Various perturbation measures are considered and computationally tractable formulae are derived. The results are applied to a class of retarded delay differential equations. Special properties of the pseudospectra of such equations are determined and illustrated.

Wim Michiels; Kirk Green; Thomas Wagenknecht; Silviu-Iulian Niculescu

2006-01-01

250

Pseudospectra and stability radii for analytic matrix functions with application to time-delay systems  

Microsoft Academic Search

Denitions for pseudospectra and stability radii of an analytic matrix function are given, where the structure of the function is exploited. Various perturbation meas- ures are considered and computationally tractable formulae are derived. The results are applied to a class of retarded delay dieren tial equations. Special properties of the pseudospectra of such equations are determined and illustrated.

Wim Michiels; Kirk Green; Thomas Wagenknecht; Silviu-Iulian Niculescu

2005-01-01

251

Pseudospectra for analytic matrix functions and application to time-delay systems  

Microsoft Academic Search

Definitions for pseudospectra of an analytic matrix function are given, where the structure of the function is exploited. Various perturbation measures are considered and computationally tractable formulae are derived. The results are applied to a class of retarded delay differential equations. Special properties of the pseudospectra of such equations are determined and illustrated.

Wim Michiels; Kirk Green; Thomas Wagenknecht; Silviu-Iulian Niculescu

2005-01-01

252

A Squared Smoothing Newton Method for Nonsmooth Matrix Equations and Its Applications in Semidefinite Optimization Problems  

Microsoft Academic Search

We study a smoothing Newton method for solving a nonsmooth matrix equation that includes semidenite programming and the semidenite complementarity problem as special cases. This method, if specialized for solving semidenite programs, needs to solve only one linear system per iteration and achieves quadratic convergence under strict complementarity and nondegeneracy. We also establish quadratic convergence of this method applied to

Jie Sun; Defeng Sun; Liqun Qi

2004-01-01

253

Downlink channel covariance matrix (DCCM) estimation and its applications in wireless DS-CDMA systems  

Microsoft Academic Search

The downlink channel covariance matrix (DCCM) is of vital importance in determining downlink beamforming weights for base station (BS) antenna array systems. For the frequency-di- vision-duplex (FDD) mode, DCCM is difficult to obtain due to a lack of direct measurement of downlink channel responses. In this paper, a novel technique is proposed for estimating DCCM using uplink channel responses only,

Ying-chang Liang; Francois P. S. Chin

2001-01-01

254

A Delphi-matrix approach to SEA and its application within the tourism sector in Taiwan  

SciTech Connect

Strategic Environmental Assessment (SEA) is a procedural tool and within the framework of SEA, several different types of analytical methods can be used in the assessment. However, the impact matrix used currently in Taiwan has some disadvantages. Hence, a Delphi-matrix approach to SEA is proposed here to improve the performance of Taiwan's SEA. This new approach is based on the impact matrix combination with indicators of sustainability, and then the Delphi method is employed to collect experts' opinions. In addition, the assessment of National Floriculture Park Plan and Taiwan Flora 2008 Program is taken as an example to examine this new method. Although international exhibition is one of the important tourism (economic) activities, SEA is seldom about tourism sector. Finally, the Delphi-matrix approach to SEA for tourism development plan is established containing eight assessment topics and 26 corresponding categories. In summary, three major types of impacts: resources' usages, pollution emissions, and local cultures change are found. Resources' usages, such as water, electricity, and natural gas demand, are calculated on a per capita basis. Various forms of pollution resulting from this plan, such as air, water, soil, waste, and noise, are also identified.

Kuo, N.-W. [Graduate Institute of Tourism and Health Science, National Taipei College of Nursing, Taiwan (China)]. E-mail: ibis@ntcn.edu.tw; Hsiao, T.-Y. [Department of Tourism Industry, Jin-Wen Institute of Technology, Taiwan (China); Yu, Y.-H. [Graduate Institute of Environmental Engineering, National Taiwan University, Taiwan (China)

2005-04-15

255

Exploiting discriminant information in nonnegative matrix factorization with application to frontal face verification  

Microsoft Academic Search

Abstract In this paper, two supervised methods for enhancing the classification accuracy of the Non- negative Matrix Factorization (NMF) algorithm are presented. The idea is to extend the NMF algorithm in order to extract features that enforce not only the spatial locality, but also the separability between,classes in a discriminant manner. The first method,em ploys discriminant analysis in the features

Stefanos Zafeiriou; Anastasios Tefas; Ioan Buciu; Ioannis Pitas

2006-01-01

256

The Application of an Enamel Matrix Protein Derivative (Emdogain®) in Regenerative Periodontal Therapy: A Review  

Microsoft Academic Search

Regenerative periodontal therapy aims at reconstitution of the lost periodontal structures such as new formation of root cementum, periodontal ligament and alveolar bone. Findings from basic research indicate that enamel matrix protein derivative (EMD) has a key role in periodontal wound healing. Histological results from animal and human studies have shown that treatment with EMD promotes periodontal regeneration. Moreover, clinical

Anton Sculean; Frank Schwarz; Jürgen Becker; Michel Brecx

2007-01-01

257

Evaluation of matrix type mucoadhesive tablets containing indomethacin for buccal application.  

PubMed

Nonsteroidal anti-inflammatory drugs (NSAIDs) are administered for pain relief from oral mucositis. However, the systemic administration of NSAIDs is limited due to systemic side effects. To avoid these side effects and treat local lesions effectively, a matrix type mucoadhesive tablet was developed. A mixture of hard fat, ethylcellulose (EC) and polyethylene glycol (PEG) was used as a matrix base, and indomethacin (IMC) was used as the principal agent. In tablets consisting of hard fat, EC and IMC, the drug release was sustained. In tablets consisting of hard fat, EC, considerable amounts of PEG and IMC, the drug release was relatively increased and IMC existed as the molecular phase or in an amorphous state. The in vitro adhesive force of the tablets consisting of hard fat, EC, considerable amounts of PEG and IMC was significantly increased as compared with the tablets consisting of hard fat and IMC. A significantly high tissue concentration and significantly low plasma concentration were observed after buccal administration of this matrix type mucoadhesive tablet as compared with that after oral administration of IMC. Thus, the matrix type mucoadhesive tablet has good potential as a preparation for the treatment of pain due to oral aphtha. PMID:23791737

Ikeuchi-Takahashi, Yuri; Sasatsu, Masanaho; Onishi, Hiraku

2013-09-10

258

A penalized matrix decomposition, with applications to sparse principal components and canonical correlation analysis  

PubMed Central

We present a penalized matrix decomposition (PMD), a new framework for computing a rank-K approximation for a matrix. We approximate the matrix X as , where dk, uk, and vk minimize the squared Frobenius norm of X, subject to penalties on uk and vk. This results in a regularized version of the singular value decomposition. Of particular interest is the use of L1-penalties on uk and vk, which yields a decomposition of X using sparse vectors. We show that when the PMD is applied using an L1-penalty on vk but not on uk, a method for sparse principal components results. In fact, this yields an efficient algorithm for the “SCoTLASS” proposal (Jolliffe and others 2003) for obtaining sparse principal components. This method is demonstrated on a publicly available gene expression data set. We also establish connections between the SCoTLASS method for sparse principal component analysis and the method of Zou and others (2006). In addition, we show that when the PMD is applied to a cross-products matrix, it results in a method for penalized canonical correlation analysis (CCA). We apply this penalized CCA method to simulated data and to a genomic data set consisting of gene expression and DNA copy number measurements on the same set of samples.

Witten, Daniela M.; Tibshirani, Robert; Hastie, Trevor

2009-01-01

259

Matrix reorganization and dynamic programming: Applications to paired comparisons and unidimensional seriation  

Microsoft Academic Search

A recursive dynamic programming strategy is discussed for optimally reorganizing the rows and simultaneously the columns of ann ×n proximity matrix when the objective function measuring the adequacy of a reorganization has a fairly simple additive structure. A number of possible objective functions are mentioned along with several numerical examples using Thurstone's paired comparison data on the relative seriousness of

L. J. Hubert; R. G. Golledge

1981-01-01

260

Residual energy applications program test and operations report  

SciTech Connect

Objective of REAP in the recovery of waste heat at US gaseous diffusion plants by 1984. This report contains policy, objective, and guideline suggestions for utilizing the proposed Energy applied Systems Test (EAST) Facility and for managing EAST operations; preliminary design information on facility support equipment and physical plant; and estimates of initial construction costs and staffing requirements for a two-bay, three-shift operation. (DCL)

Zander, F.H.

1980-10-01

261

Bayesian Copulae Distributions, with Application to Operational Risk Management  

Microsoft Academic Search

The aim of this paper is to introduce a new methodology for operational risk management, based on Bayesian copulae. One of the main problems related to operational risk management is understanding the complex dependence structure of the\\u000a associated variables. In order to model this structure in a flexible way, we construct a method based on copulae. This allows\\u000a us to

Luciana Dalla Valle

2009-01-01

262

Continuous SiC fiber, CVI SiC matrix composites for nuclear applications: Properties and irradiation effects  

NASA Astrophysics Data System (ADS)

Silicon carbide (SiC) continuous fiber-reinforced, SiC-matrix composites (SiC/SiC composites) are industrially available materials that are promising for applications in nuclear environments. The SiC/SiC composites consisting of near-stoichiometric SiC fibers, stoichiometric and fully crystalline SiC matrices, and the pyrocarbon (PyC) or multilayered PyC/SiC interphase between the fiber and the matrix are considered particularly resistant to very high radiation environments. This paper provides a summary compilation of the properties of these composites, specifically those with the chemically vapor-infiltrated (CVI) SiC matrices, including newly obtained results. The properties discussed are both in unirradiated condition and after neutron irradiation to intermediate fluence levels (most data are for

Katoh, Yutai; Ozawa, Kazumi; Shih, Chunghao; Nozawa, Takashi; Shinavski, Robert J.; Hasegawa, Akira; Snead, Lance L.

2014-05-01

263

Integrating Matrix Method for Determining the Natural Vibrations of a Rotating, Unsymmetrical Beam with Application to Twisted Propeller Blades  

NASA Technical Reports Server (NTRS)

A numerical method is Presented for determining the natural vibration frequencies, and the corresponding mode shapes, of a rotating cantilever beam which has a nonuniform, unsymmetrical cross section. Two coupled fourth-order differential equations of motion with variable coefficients are derived which govern the motion of such a beam having deformations in two directions. Through the development and utilization of the integrating matrix, the solution of the differential equations is obtained in the form of an eigenvalue problem. The solutions to the eigenvalue problem are determined by an iteration method based upon a special orthogonality relationship which is derived. Numerical examples, including an application to a twisted propeller blade, are presented with the results of the integrating matrix solutions being compared to exact solutions and experimental data.

Hunter, William F.

1967-01-01

264

The OCLC Network: Its Architecture, Application, and Operation.  

ERIC Educational Resources Information Center

This overview of the OCLC telecommunications network discusses: its scope and applications, user demographics, the system architecture, access, costs, protocols, maintenance, vendor relationships, performance data, and network engineering. (13 references) (MES)

Learn, Larry L.; Carpenter, George L.

1988-01-01

265

Sub-operating systems: a new approach to application security  

Microsoft Academic Search

Users regularly exchange apparently innocuous data files using email and ftp. While the users view these data as passive, there are situations when they are interpreted as code by some system application. In that case the data become \\

Sotiris Ioannidis; Steven M. Bellovin; Jonathan M. Smith

2002-01-01

266

Polar Satellite Products for the Operational Meteorologist, Module 2: Microwave Products and Applications  

NSDL National Science Digital Library

Polar Satellite Products for the Operational Forecaster will be a series of short Web-based lessons that demonstrate the use of polar satellite imagery and derived products in a variety of settings. POES 2: Microwave Products and Applications focuses on microwave applications from the AMSU and SSM/I instruments and includes descriptions and examples of the operational and experimental microwave products available.

Spangler, Tim

1996-10-01

267

Software ergonomics: effects of computer application design parameters on operator task performance and health  

Microsoft Academic Search

Evidence is reviewed that the operating characteristics of computer application systems, in addition to physical characteristics of display units (CRTs), are the cause of many observed effects on operator health and task effectiveness. These effects are hypothesized to occur through changes in task structure, and the man-machine redivision of labour that results when computer application systems are introduced into work

JON A. TURNER; ROBERT A. KARASEK JR

1984-01-01

268

Operational applications of remote sensing in hydrology: success, prospects and problems  

Microsoft Academic Search

The use of remote sensing information in operational hydrology is relatively limited, but specific examples can be cited for determining precipitation, soil moisture, groundwater, snow, surface water and basin characteristics. The application of remote sensing in hydrology can be termed operational if at least one of two conditions are met: (a) the application produces an output on a regular basis,

ALBERT RANGO; AHLAM I. SHALABY

1999-01-01

269

26 CFR 1.1502-21A - Consolidated net operating loss deduction generally applicable for consolidated return years...  

... 2014-04-01 false Consolidated net operating loss deduction generally applicable...1997 § 1.1502-21A Consolidated net operating loss deduction generally applicable... (a) In general. The consolidated net operating loss deduction shall be an...

2014-04-01

270

26 CFR 1.1502-21A - Consolidated net operating loss deduction generally applicable for consolidated return years...  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 false Consolidated net operating loss deduction generally applicable...1997 § 1.1502-21A Consolidated net operating loss deduction generally applicable... (a) In general. The consolidated net operating loss deduction shall be an...

2012-04-01

271

26 CFR 1.1502-21A - Consolidated net operating loss deduction generally applicable for consolidated return years...  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 false Consolidated net operating loss deduction generally applicable...1997 § 1.1502-21A Consolidated net operating loss deduction generally applicable... (a) In general. The consolidated net operating loss deduction shall be an...

2011-04-01

272

Research and operational applications in multi-center ensemble forecasting  

NASA Astrophysics Data System (ADS)

The North American Ensemble Forecast System (NAEFS) was built up in 2004 by the Meteorological Service of Canada (MSC), the National Meteorological Service of Mexico (NMSM), and the US National Weather Service (NWS) as an operational multi-center ensemble forecast system. Currently it combines the 20-member MSC and NWS ensembles to form a joint ensemble of 40 members twice a day. The joint ensemble forecast, after bias correction and statistical downscaling, is used to generate a suite of products for CONUS, North America and for other regions of the globe. The THORPEX Interactive Grand Global Ensemble (TIGGE) project has been established a few years ago to collect operational global ensemble forecasts from world centers, and distribute to the scientific community, to encourage research leading to the acceleration of improvements in the skill and utility of high impact weather forecasts. TIGGE research is expected to advise the development of the operational NAEFS system and eventually the two projects are expected to converge into a single operational system, the Global Interactive Forecast System (GIFS). This presentation will review recent developments, the current status, and plans related to the TIGGE research and NAEFS operational multi-center ensemble projects.

Zhu, Y.; Toth, Z.

2009-05-01

273

47 CFR 25.137 - Application requirements for earth stations operating with non-U.S. licensed space stations.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Application requirements for earth stations operating with non-U.S. licensed...COMMUNICATIONS Applications and Licenses Earth Stations § 25.137 Application requirements for earth stations operating with non-U.S....

2013-10-01

274

47 CFR 25.137 - Application requirements for earth stations operating with non-U.S. licensed space stations.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 false Application requirements for earth stations operating with non-U.S. licensed...COMMUNICATIONS Applications and Licenses Earth Stations § 25.137 Application requirements for earth stations operating with non-U.S....

2009-10-01

275

47 CFR 25.137 - Application requirements for earth stations operating with non-U.S. licensed space stations.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Application requirements for earth stations operating with non-U.S. licensed...COMMUNICATIONS Applications and Licenses Earth Stations § 25.137 Application requirements for earth stations operating with non-U.S....

2010-10-01

276

40 CFR 63.5734 - What standards must I meet for resin and gel coat application equipment cleaning operations?  

Code of Federal Regulations, 2010 CFR

...What standards must I meet for resin and gel coat application equipment cleaning operations...Manufacturing Standards for Resin and Gel Coat Application Equipment Cleaning Operations...What standards must I meet for resin and gel coat application equipment cleaning...

2010-07-01

277

40 CFR 63.5734 - What standards must I meet for resin and gel coat application equipment cleaning operations?  

Code of Federal Regulations, 2010 CFR

...What standards must I meet for resin and gel coat application equipment cleaning operations...Manufacturing Standards for Resin and Gel Coat Application Equipment Cleaning Operations...What standards must I meet for resin and gel coat application equipment cleaning...

2009-07-01

278

Operator assistant systems - An experimental approach using a telerobotics application  

NASA Technical Reports Server (NTRS)

This article presents a knowledge-based system methodology for developing operator assistant (OA) systems in dynamic and interactive environments. This is a problem both of training and design, which is the subject of this article. Design includes both design of the system to be controlled and design of procedures for operating this system. A specific knowledge representation is proposed for representing the corresponding system and operational knowledge. This representation is based on the situation recognition and analytical reasoning paradigm. It tries to make explicit common factors involved in both human and machine intelligence, including perception and reasoning. An OA system based on this representation has been developed for space telerobotics. Simulations have been carried out with astronauts and the resulting protocols have been analyzed. Results show the relevance of the approach and have been used for improving the knowledge representation and the OA architecture.

Boy, Guy A.; Mathe, Nathalie

1993-01-01

279

MIL-H-8501B: Application to shipboard terminal operations  

NASA Technical Reports Server (NTRS)

The philosophy and structure of the proposed U.S. Military Specification for Handling Qualities Requirements for Military Rotorcraft, MIL-H-8501B, are presented with emphasis on shipboard terminal operations. The impact of current and future naval operational requirements on the selection of appropriate combinations of basic vehicle dynamics and usable cue environments are identified. An example 'walk through' of MIL-H-8501B is conducted from task identification to determination of stability and control requirements. For selected basic vehicle dynamics, criteria as a function of input/response magnitude are presented. Additionally, rotorcraft design development implications are discussed.

Cappetta, A. N.; Johns, J. B.

1993-01-01

280

Ferrocene carboxaldehyde thin films grown by matrix-assisted pulsed laser evaporation for non linear optical applications  

NASA Astrophysics Data System (ADS)

Thin films of ferrocene carboxaldehyde, also known as cyclopentadienyl(formylcyclopentadienyl)iron, were grown on silicon and glass substrates by matrix-assisted pulsed laser evaporation technique, using a Nd:YAG device operating at 266 nm (4?). Spectroscopic-ellipsometry, Fourier transform infrared spectroscopy, scanning electron microscopy and atomic force microscopy investigations revealed that the films are homogeneous in thickness, with dense morphology and without cracks, low surface roughness (?11 nm), and no significant chemical damage. Second harmonic generation capabilities of the thin films were evidenced by using a femtosecond Ti:sapphire laser.

Constantinescu, Catalin; Matei, Andreea; Ion, Valentin; Mitu, Bogdana; Ionita, Iulian; Dinescu, Maria; Luculescu, Catalin. R.; Vasiliu, Cristina; Emandi, Ana

2014-05-01

281

Application of T-matrix method in solving mixed boundary separable obstacle problem.  

PubMed

The practical problem of imaging scatterers enclosed by separable obstacles with mixed boundary is addressed. Both the unknown scatterers and the known obstacle media can be mixture of dielectric and perfect electric conducting (PEC) materials. The scattering phenomenon of such problem is well modeled by T-matrix method. By usage of separable prior information, the obstacle media are treated as known scatterers rather than part of the background. The number of unknowns is thus reduced greatly. After recovering the profiles of scatterers by T-matrix method, a criterion is further provided to classify the PEC and dielectric scatterers. Various numerical examples are presented to show the effectiveness and good performance of the method. PMID:24977878

Ye, Xiuzhu; Song, Rencheng; Chen, Xudong

2014-06-30

282

Finite element applications to explore the effects of partial bonding on metal matrix composite properties  

NASA Technical Reports Server (NTRS)

The mechanics of materials approach (definition of E, G, Nu, and Alpha) and the finite element method are used to explore the effects of partial bonding and fiber fracture on the behavior of high temperature metal matrix composites. Composite ply properties are calculated for various degrees of disbonding to evaluate the sensitivity of these properties to the presence of fiber/matrix disbonding and fiber fracture. The mechanics of materials approach allows for the determination of the basic ply material properties needed for design/analysis of composites. The finite element method provides the necessary structural response (forces and displacements) for the mechanics of materials equations. Results show that disbonding of fractured fibers affect only E sub (111) and alpha sub (111) significantly.

Caruso, J. J.; Trowbridge, D.; Chamis, C. C.

1989-01-01

283

An improved Newton iteration for the generalized inverse of a matrix, with applications  

NASA Technical Reports Server (NTRS)

The purpose here is to clarify and illustrate the potential for the use of variants of Newton's method of solving problems of practical interest on highly personal computers. The authors show how to accelerate the method substantially and how to modify it successfully to cope with ill-conditioned matrices. The authors conclude that Newton's method can be of value for some interesting computations, especially in parallel and other computing environments in which matrix products are especially easy to work with.

Pan, Victor; Schreiber, Robert

1990-01-01

284

A Statistical Framework for Optimal Design Matrix Generation With Application to fMRI  

Microsoft Academic Search

The general linear model (GLM) is a well established tool for analyzing\\u000afunctional magnetic resonance imaging (fMRI) data. Most fMRI analyses via GLM\\u000aproceed in a massively univariate fashion where the same design matrix is used\\u000afor analyzing data from each voxel. A major limitation of this approach is the\\u000alocally varying nature of signals of interest as well as

Gautam V. Pendse; Richard Baumgartner; Adam J. Schwarz; Alexandre Coimbra; David Borsook; Lino Becerra

2010-01-01

285

Preliminary Investigation by Raman Spectroscopy of Some Polymeric Matrix with Pharmaceutical Applications  

NASA Astrophysics Data System (ADS)

The possibility to use poly(ethylene oxide) as a polymeric matrix for some pharmaceutical products was analyzed. The behavior of the polymer in the aqueous solutions and the possible interactions between the polymer and the clotrimazole were investigated by Raman spectroscopy. Repeated action of the water on the polymeric conformation is a reversible process and the introduction of the clotrimazole in the polymeric gel do not modify the properties of the active substance of the pharmaceutical product.

Todica, M.; Pop, C. V.; Dinte, E.; Farcau, C.; Astilean, S.

286

Technical evaluation of MALDI-TOF mass spectrometry for quantitative proteomic profiling matrix formulation and application  

Microsoft Academic Search

Matrix-assisted laser desorption\\/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) has been recently used to identify\\u000a disease markers by directly profiling and quantifying the peptide\\/proteins in biological samples under different physiological\\u000a or experimental conditions. The information of reproducibility of such quantitative profiling method has not been available.\\u000a It is important to evaluate and reduce error from technical variation. In this study, an

Ronald T. K. Pang; Philip J. Johnson; Charles M. L. Chan; Ebenezer K. C. Kong; Anthony T. C. Chan; Joseph J. Y. Sung; Terence C. W. Poon

2004-01-01

287

Design of a Decision Support Architecture for Human Operators in UAV Fleet C2 Applications  

Microsoft Academic Search

UAVs are becoming indispensable assets for military command and control applications such as surveillance, reconnaissance, search and rescue operations because of their superiorities over manned vehicles. Nevertheless, humans are still needed for high-level guidance and commanding of UAVs in those oper- ations for their intelligence and higher level of flexibility in decision making. Within this new position, human operators are

Oktay Arslan; Gokhan Inalhan

2009-01-01

288

An Operator Calculus Having Applications in Quantum Electrodynamics  

Microsoft Academic Search

An alteration in the notation used to indicate the order of operation of noncommuting quantities is suggested. Instead of the order being defined by the position on the paper, an ordering subscript is introduced so that AsBs' means AB or BA depending on whether s exceeds s' or vice versa. Then As can be handled as though it were an

Richard P. Feynman

1951-01-01

289

Fast Explicit Operator Splitting Method. Application to the Polymer System  

Microsoft Academic Search

Computing solutions of convection-diffusion equations, especially in the convection dominated case, is an important and challenging problem that requires development of fast, reliable numerical methods. We propose a second-order fast explicit operator splitting (FEOS) method based on the Strang splitting. The main idea of the method is to solve the parabolic problem via a discretization of the formula for the

Alina Chertock; Alexander Kurganov; Guergana Petrova

290

Spaceborne GNSS Radio Occultation Instrumentation for Operational Applications  

Microsoft Academic Search

Radio occultation (RO) instruments using GNSS signals are specialised spaceborne receivers designed to provide highly accurate measurements from which one can derive vertical profiles of the temperature, pressure and humidity in the atmosphere, as well as profiles of electron content in the ionosphere. A family of operational RO instruments is being developed for a number of European space projects since

R. Bagge; M. Bonnedal; A. Carlström; J. Christensen; M. Hägg; T. Lindgren

291

Research and operational applications in multi-center ensemble forecasting  

Microsoft Academic Search

The North American Ensemble Forecast System (NAEFS) was built up in 2004 by the Meteorological Service of Canada (MSC), the National Meteorological Service of Mexico (NMSM), and the US National Weather Service (NWS) as an operational multi-center ensemble forecast system. Currently it combines the 20-member MSC and NWS ensembles to form a joint ensemble of 40 members twice a day.

Y. Zhu; Z. Toth

2009-01-01

292

Application of Bayesian Inference to Operational Risk Management  

Microsoft Academic Search

Abstract Bayesian inference that is able ,to combine ,statistical measurement approach,and scenario analysis is effective exceedingly,for measuring operational risk. In choosing the prior distribution, taking indicators that may be predictive of the risk of future losses, external circumstance,and ,so forth ,into consideration ,makes ,it possible ,to obtain more realistic risk amount, this process itself is an important

Yuji Yasuda

2003-01-01

293

Applications of Optimal Building Energy System Selection and Operation  

SciTech Connect

Berkeley Lab has been developing the Distributed Energy Resources Customer Adoption Model (DER-CAM) for several years. Given load curves for energy services requirements in a building microgrid (u grid), fuel costs and other economic inputs, and a menu of available technologies, DER-CAM finds the optimum equipment fleet and its optimum operating schedule using a mixed integer linear programming approach. This capability is being applied using a software as a service (SaaS) model. Optimisation problems are set up on a Berkeley Lab server and clients can execute their jobs as needed, typically daily. The evolution of this approach is demonstrated by description of three ongoing projects. The first is a public access web site focused on solar photovoltaic generation and battery viability at large commercial and industrial customer sites. The second is a building CO2 emissions reduction operations problem for a University of California, Davis student dining hall for which potential investments are also considered. And the third, is both a battery selection problem and a rolling operating schedule problem for a large County Jail. Together these examples show that optimization of building u grid design and operation can be effectively achieved using SaaS.

Marnay, Chris; Stadler, Michael; Siddiqui, Afzal; DeForest, Nicholas; Donadee, Jon; Bhattacharya, Prajesh; Lai, Judy

2011-04-01

294

Applications of Optimal Building Energy System Selection and Operation  

Microsoft Academic Search

Berkeley Lab has been developing the Distributed Energy Resources Customer Adoption Model (DER-CAM) for several years. Given load curves for energy services requirements in a building microgrid (u grid), fuel costs and other economic inputs, and a menu of available technologies, DER-CAM finds the optimum equipment fleet and its optimum operating schedule using a mixed integer linear programming approach. This

Chris Marnay; Michael Stadler; Afzal Siddiqui; Nicholas DeForest; Jon Donadee; Prajesh Bhattacharya; Judy Lai

2011-01-01

295

Application of multivariate statistical process control to batch operations  

Microsoft Academic Search

This paper summarises the results of a 2-year study focusing on the development of a condition monitoring system for a fed-batch fermentation system operated by Biochemie Ltd. in Austria. Consumer pressure has esulted in a greater emphasis in industry on product quality. As a direct consequence, the importance of accurate process monitoring has increased steadily in recent years. This paper

B. Lennox; H. G. Hiden; G. A. Montague; G. Kornfeld; P. R. Goulding

2000-01-01

296

Optical butterfly interconnections and applications in optical logic operations  

NASA Astrophysics Data System (ADS)

In this paper, the optical butterfly interconnections have first been implemented in theory and experiment by using the special reflected interconnect gratings and liquid crystal light valve (LCLV), and two most primitive optical logic operations (AND and OR) have been completed on the basis in parallel. Hence, this work makes the fundamental for more complex digital optical computings.

Sun, Degui; Wang, Na-Xin; Weng, Zhao-Heng

1993-02-01

297

Application of partition matrix methods to solve large eigenproblems in structural dynamics  

NASA Astrophysics Data System (ADS)

Eigenvalue and eigenvector problems are addressed for large, sparse matrices resulting from the vibration analysis of complex structures. Problems of this type are computationally intensive and have traditionally been solved using supercomputers. Partitioned matrices are employed, herein, to produce a set of out-of-core algorithms which can be used for eigenproblems with several thousand degrees-of-freedom. The efficiency of a Rayleigh-Ritz iterative procedure, based on partitioned matrices, is compared with competing out-of-core eigensolution strategies. These results demonstrate that partition matrix algorithms are computationally competitive and may be implemented successfully across a wide range of computers to solve large eigenproblems. The partition matrix routines are implemented as extensions of the widely used commercial software system MATLAB. These extensions employ compiled FORTRAN routines which are linked into MATLAB and provide a set of user friendly analysis tools that are easily employed to solve eigenproblems which were previously too large for this environment. Both workstations and supercomputers were used to evaluate the efficiency of the partition matrix algorithms. Additionally, a parallelized version of the software was implemented across a cluster of workstations. The parallelized code demonstrates the practicality of using a cluster of workstations to efficiently solve large eigenproblems typically requiring the use of a supercomputer.

Turcotte, Louis Harvie

298

Probabilistic non-negative matrix factorization: theory and application to microarray data analysis.  

PubMed

Non-negative matrix factorization (NMF) has proven to be a useful decomposition technique for multivariate data, where the non-negativity constraint is necessary to have a meaningful physical interpretation. NMF reduces the dimensionality of non-negative data by decomposing it into two smaller non-negative factors with physical interpretation for class discovery. The NMF algorithm, however, assumes a deterministic framework. In particular, the effect of the data noise on the stability of the factorization and the convergence of the algorithm are unknown. Collected data, on the other hand, is stochastic in nature due to measurement noise and sometimes inherent variability in the physical process. This paper presents new theoretical and applied developments to the problem of non-negative matrix factorization (NMF). First, we generalize the deterministic NMF algorithm to include a general class of update rules that converges towards an optimal non-negative factorization. Second, we extend the NMF framework to the probabilistic case (PNMF). We show that the Maximum a posteriori (MAP) estimate of the non-negative factors is the solution to a weighted regularized non-negative matrix factorization problem. We subsequently derive update rules that converge towards an optimal solution. Third, we apply the PNMF to cluster and classify DNA microarrays data. The proposed PNMF is shown to outperform the deterministic NMF and the sparse NMF algorithms in clustering stability and classification accuracy. PMID:24467759

Bayar, Belhassen; Bouaynaya, Nidhal; Shterenberg, Roman

2014-02-01

299

Application of the transfer matrix for tuning the CSNS-DTL  

NASA Astrophysics Data System (ADS)

In the construction of a drift tube LINAC (DTL), many factors caused during the fabrication and assembly of the structure cells cause the electric field distribution not as the same as the design curve. To solve this problem, the traditional way is to solve the equation of Slater's perturbation theorem to obtain the electrical field variation due to local frequency shift. However, that is very difficult under complicated conditions. Since the field perturbation equation is similar to the particle's transverse motion equation, which can be simply solved by using the transfer matrix method, we thus propose to apply a transfer matrix method in tuning the DTL. We demonstrate the availability and advantages of this method with 3D microwave code simulation and the LabVIEW calculation program. After two iterations, the initial error of the electric field of 19.5% has been improved greatly down to 1.3%-4.5%. This indicates that the transfer matrix method is very useful and convenient for the simplification of tuning procedures.

Li, A.-Hong; Yin, Xue-Jun; Fu, Shi-Nian; Sun, Zhi-Rui

2011-10-01

300

Microwave-Induced Sintering of Cu-Based Metallic Glass Matrix Composites in a Single-Mode 915-MHz Applicator  

NASA Astrophysics Data System (ADS)

Using a single-mode 915-MHz microwave applicator equipped with a ceramic pressing unit, we processed the gas-atomized Cu50Zr45Al5 metallic glassy alloy powder blended with Sn powder of various contents in a separated magnetic (H-) field maximum. The blended powders were well heated in H-field. Bulk Cu50Zr45Al5 metallic glass matrix composites were produced with an applied pressure of 5 MPa. As a secondary phase, the Sn particle promoted the densification of the sintered samples.

Li, Song; Xie, Guoqiang; Louzguine-Luzgin, Dmitri V.; Sato, Motoyasu; Inoue, Akihisa

2011-06-01

301

Autonomous Robots in SWAT Applications: Research, Design, and Operations Challenges  

Microsoft Academic Search

This paper describes the efforts of Stanford University's Aerospace Robotics Laboratory (ARL), the Palo Alto - Mountain View (California) Regional Special Weapons and Tactics (SWAT) team, and the MLB Company to bridge the gap between the perception of potential uses of autonomous robots in police SWAT environments and the reality of their application. The ARL researchers were given freedom of

Henry L Jones; Steve Morris

302

Risk and safety analysis for Florida commercial aerial application operations  

NASA Astrophysics Data System (ADS)

The purpose of this study was to determine self-reported perceptions in the areas of agroterrorism, bioterrorism, chemical exposure and Federal Aviation Administration (FAA) oversight. The aerial application industry has been in existence since the 1920's with a gamut of issues ranging from pesticide drift to counterterrorism. The attacks of September 11th, 2001, caused a paradigm shift in the way the United States views security and, more importantly, the prevention of malicious activity. Through the proper implementation and dissemination of educational materials dealing with industry specific concerns, it is imperative that everyone has the proper level of resources and training to effectively manage terrorist threats. This research study was designed to interpret how aerial applicators view these topics of concern and how they perceive the current threat level of terrorism in the industry. Research results were consistent, indicating that a high number of aerial applicators in the state of Florida are concerned with these topics. As a result, modifications need to be made with respect to certain variables. The aerial application industry works day in and day out to provide a professional service that helps maintain the integrity of the food and commodities that we need to survive. They are a small percentage of the aviation community that we all owe a great deal for the vital and necessary services they provide.

Robbins, John Michael

303

Electrical power distribution system operating experience review for fusion applications  

Microsoft Academic Search

This paper describes safety research on electrical distribution systems applicable to fusion facilities. Electrical power has many uses in both magnetic and inertial fusion experiments; it is the most important support system for any fusion experiment. Electricity powers a wide variety of plant equipment, including vacuum pumps, magnets, coolant pumps, air handlers, compressors, and either plasma heating or target implosion

L. C Cadwallader

2002-01-01

304

Applications of Genetic Methods to NASA Design and Operations Problems  

NASA Technical Reports Server (NTRS)

We review four recent NASA-funded applications in which evolutionary/genetic methods are important. In the process we survey: the kinds of problems being solved today with these methods; techniques and tools used; problems encountered; and areas where research is needed. The presentation slides are annotated briefly at the top of each page.

Laird, Philip D.

1996-01-01

305

Options for organization and operation of space applications transfer centers  

NASA Technical Reports Server (NTRS)

The benefits of developing regional facilities for transfer of NASA developed technology are discussed. These centers are designed to inform, persuade, and serve users. Included will be equipment for applications and demonstrations of the processes, a library, training facilities, and meeting rooms. The staff will include experts in the various techniques, as well as personnel involved in finding and persuading potential users.

Robinson, A. C.; Madigan, J. A.

1976-01-01

306

FIELD APPLICATIONS OF ROBOTIC SYSTEMS IN HAZARDOUS WASTE SITE OPERATIONS  

EPA Science Inventory

The cleanup of hazardous waste sites is a challenging and complex field that offers numerous opportunities for the application of robotic technology. he contamination problem, long in the making, will take decades to resolve. ur ingenuity in developing robotic tools to assist in ...

307

Peri-operative warming devices: performance and clinical application.  

PubMed

Since the adverse consequences of accidental peri-operative hypothermia have been recognised, there has been a rapid expansion in the development of new warming equipment designed to prevent it. This is a review of peri-operative warming devices and a critique of the evidence assessing their performance. Forced-air warming is a common and extensively tested warming modality that outperforms passive insulation and water mattresses, and is at least as effective as resistive heating. More recently developed devices include circulating water garments, which have shown promising results due to their ability to cover large surface areas, and negative pressure devices aimed at improving subcutaneous perfusion for warming. We also discuss the challenge of fluid warming, looking particularly at how devices' performance varies according to flow rate. Our ultimate aim is to provide a guide through the bewildering array of devices on the market so that clinicians can make informed and accurate choices for their particular hospital environment. PMID:24720346

John, M; Ford, J; Harper, M

2014-06-01

308

Electric Submersible Pump Application and Operation in Small Openhole Completions  

Microsoft Academic Search

Amoco Production Co. has operated electric submersible pumps (ESP's) in 4 3\\/4-in. (12.1-cm) open holes in the Grayburg formation of its Midland Farms Unit, Andrews Dist., since 1977. The Midland Farms (Grayburg) reservoir is a low-pressure (400- to 600-psi (2.8- to 4.1-MPa) static bottomhole pressure (BHP)), high-PI (ranging from one to seven) formation that requires artificial lift drawdown to 70-psi

W. J. McClung; J. A. Johnson

1983-01-01

309

Application of Reactive Barriers Operated in Frozen Ground  

Microsoft Academic Search

Permeable reactive barriers allow passive treatment of contaminated groundwater. Barriers, filled with reactive media, are\\u000a able to treat a wide range of contaminants including dissolved nutrients and metals, petroleum hydrocarbons and chlorinated\\u000a organic compounds. Advantages for areas of frozen ground include low energy requirements, the ability to function unattended,\\u000a and a low cost of operation. Although freeze-thaw cycling poses additional

Damian B. Gore

310

Applications of triggered lightning to space vehicle operations  

NASA Technical Reports Server (NTRS)

Kennedy Space Center (KSC) and the USAF Eastern Space Missile Center (ESMC) covering an area of 25 x 40 km are frequently called America's Spaceport. This title is earned through the integration, by labor and management, of many skills in a wide variety of engineering fields to solve many technical problems that occur during the launch processing of space vehicles. Weather is one of these problems, and although less frequent in time and duration when compared to engineering type problems, has caused costly and life threatening situations. This sensitivity to weather, especially lightning, was recognized in the very early pioneer days of space operations. The need to protect the many v\\facilities, space flight hardware, and personnel from electrified clouds capable of producing lightning was a critical element in improving launch operations. A KSC lightning committee was formed and directed to improve lightning protection, detection, and measuring systems and required that all theoretical studies be confirmed by KSC field data. Over the years, there have been several lightning incidents involving flight vehicles during ground processing as well as launch. Subsequent investigations revealed the need to improve these systems as well as the knowledge of the electrical atmosphere and its effects on operations in regard to cost and safety. Presented here is how, KSC Atmospheric Science Field Laboratory (AFSL), in particular Rocket Triggered Lightning, is being used to solve these problems.

Jafferis, William; Sanicandro, Rocco; Rompalla, John; Wohlman, Richard

1992-01-01

311

Lorentz-covariant surface impedance and characteristic matrix methods with applications to measurements of material parameters of linear media  

NASA Astrophysics Data System (ADS)

The impedance and characteristics matrix methods are generalized on the case of uniformly moving linear media. On this basis, the reflection and transmission operators of the boundary of two anisotropic and gyrotropic media uniformly moving with different velocities, and similar operators of a multilayer structure consisting of such media, are found. The suggested four-dimensional formalism is very useful also in solving of direct and inverse boundary value problems for linear media at rest. In the frame of this approach, a method for measuring tensors of dielectric permittivity ?, magnetic permeability ? and gyrotropy ? and ? is proposed. It enables one, by measuring reflection and transmission coefficients, to find all 36 complex components of these tensors.

Borzdov, G. N.

1992-11-01

312

Assessment of Erosion Resistance of Coated Polymer Matrix Composites for Propulsion Applications  

NASA Technical Reports Server (NTRS)

The erosion behavior of tungsten carbide-cobalt (WC-Co) coated and uncoated polymer matrix composites (PMCs) was examined with solid particle impingement using air jets. Erosion tests were conducted with Arizona road dust impinging at 20 degrees, 60 degrees, and 90 degrees angles at a velocity of 229 meters per second at both 294 and 366 K. Noncontact optical profilometry was used to measure the wear volume loss. Results indicate that the WC-Co coating enhanced erosion resistance and reduced erosion wear volume loss by a factor of nearly 2. This should contribute to longer wear lives, reduced related breakdowns, decreased maintenance costs, and increased product reliability.

Miyoshi, Kazuhisa; Sutter, James K.; Horan, Richard A.; Naik, Subhash K.; Cupp, Randall J.

2004-01-01

313

Performance of PGA (Programmable Graph Architecture) for Matrix Multiplications  

Microsoft Academic Search

Matrix multiplication is one of the primary operations in linear algebra and is useful in a wide spectrum of multimedia applications including signal and image processing. In this paper we review a novel computer architecture for matrix multiplications. This novel architecture is based on graph theory, hence the name programmable graph architecture. We discuss the performance of PGA via time

M. Peng; S. Ramani; K. W. Tang; A. Y. Oruc

2006-01-01

314

Validation of an efficient non-negative matrix factorization method and its preliminary application in Central California  

NASA Astrophysics Data System (ADS)

Positive matrix factorization (PMF) techniques have been applied in many environmental studies. The commercial version of the PMF method has a relatively moderate practical limit for the size of the input data matrix, since the computer memory and time needed for the commercial method increases quadratically with the number of elements of solution matrices. To extend the applications of the PMF techniques to large datasets, we exercised alternative methods that demand less computer memory and time. One such method, called non-negative matrix factorization (NMF) here, is extremely memory efficient, compared with the commercial PMF method. Both NMF and PMF methods are sensitive to the initialization of solution matrices, and the use of random numbers in the initialization usually starts with a large prediction error, and requires a number of model runs with different random seeds. A novel, chemical mass balance method (ROC) is introduced here to provide a reasonable initialization for the NMF method for large data sets. Both NMF and ROC methods were validated with an ideal Cross example and the benchmark example of the commercial PMF method. The NMF-ROC method was further evaluated, in terms of computer time and the prediction error, in the preliminary application to a data set that contains particle-phase polar organic compounds analyzed for a number of samples collected in Central California during the California Regional PM 10/PM 2.5 air quality study (CRPAQS, 1999-2001). The NMF-ROC method was demonstrated to perform better than the NMF, PMF and PMF-ROC methods in the CRPAQS data set. This performance enhancement is expected to be magnified for larger data sets.

Liang, Jinyou; Fairley, David

315

Matrix differentiation formulas  

NASA Technical Reports Server (NTRS)

A compact differentiation technique (without using indexes) is developed for scalar functions that depend on complex matrix arguments which are combined by operations of complex conjugation, transposition, addition, multiplication, matrix inversion and taking the direct product. The differentiation apparatus is developed in order to simplify the solution of extremum problems of scalar functions of matrix arguments.

Usikov, D. A.; Tkhabisimov, D. K.

1983-01-01

316

Two-electron Reduced-Density-Matrix Mechanics: With Application to Many-electron Atoms and Molecules  

NASA Astrophysics Data System (ADS)

In 1959 Charles Coulson popularized the challenge of computing the ground-state energy as a functional of the two-electron reduced density matrix (2-RDM) without the many-electron wavefunction. Recently, theoretical and computational advances have led to two classes of 2-RDM methods [1]: (i) the variational calculation of the 2-RDM subject to approximate N-representability conditions and (ii) the non-variational calculation of the 2-RDM from the anti-Hermitian contracted Schr"odinger equation. I will develop the background for the 2-RDM methods, discuss recent theoretical and computational advances, and present some applications, including the detection of poly-radical correlation in polyaromatic acene and aryne chains, the study of protonated acetylene and malonaldehyde beyond the Born-Oppenheimer approximation, and the computation of activation energies in pericyclic reactions of open- and closed-shell molecular species. [4pt] [1] ``Two-electron Reduced-Density-Matrix Mechanics with Application to Many-electron Atoms and Molecules,'' edited by D. A. Mazziotti, Advances in Chemical Physics Vol. 134 (Wiley, New York, 2007).

Mazziotti, David

2010-03-01

317

Graph-preserving sparse nonnegative matrix factorization with application to facial expression recognition.  

PubMed

In this paper, a novel graph-preserving sparse nonnegative matrix factorization (GSNMF) algorithm is proposed for facial expression recognition. The GSNMF algorithm is derived from the original NMF algorithm by exploiting both sparse and graph-preserving properties. The latter may contain the class information of the samples. Therefore, GSNMF can be conducted as an unsupervised or a supervised dimension reduction method. A sparse representation of the facial images is obtained by minimizing the l(1)-norm of the basis images. Furthermore, according to the graph embedding theory, the neighborhood of the samples is preserved by retaining the graph structure in the mapped space. The GSNMF decomposition transforms the high-dimensional facial expression images into a locality-preserving subspace with sparse representation. To guarantee convergence, we use the projected gradient method to calculate the nonnegative solution of GSNMF. Experiments are conducted on the JAFFE database and the Cohn-Kanade database with unoccluded and partially occluded facial images. The results show that the GSNMF algorithm provides better facial representations and achieves higher recognition rates than nonnegative matrix factorization. Moreover, GSNMF is also more robust to partial occlusions than other tested methods. PMID:20403788

Zhi, Ruicong; Flierl, Markus; Ruan, Qiuqi; Kleijn, W Bastiaan

2011-02-01

318

Three-Dimensional Supermacroporous Carrageenan-Gelatin Cryogel Matrix for Tissue Engineering Applications  

PubMed Central

A tissue-engineered polymeric scaffold should provide suitable macroporous structure similar to that of extracellular matrix which can induce cellular activities and guide tissue regeneration. Cryogelation is a technique in which appropriate monomers or polymeric precursors frozen at sub-zero temperature leads to the formation of supermacroporous cryogel matrices. In this study carrageenan-gelatin (natural polymers) cryogels were synthesized by using glutaraldehyde and 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride and N-hydroxysuccinimide (EDC-NHS) as crosslinking agent at optimum concentrations. Matrices showed large and interconnected pores which were in the range of 60–100??m diameter. Unconfined compression analysis showed elasticity and physical integrity of all cryogels, as these matrices regained their original length after 90% compressing from the original size. Moreover Young's modulus was found to be in the range of 4–11?kPa for the dry cryogel sections. These cryogels also exhibited good in vitro degradation capacity at 37 °C within 4 weeks of incubation. Supermacroporous carrageenan-gelatin cryogels showed efficient cell adherence and proliferation of Cos-7 cells which was examined by SEM. PI nuclear stain was used to observe cell-matrix interaction. Cytotoxicity of the scaffolds was checked by MTT assay which showed that cryogels are biocompatible and act as a potential material for tissue engineering and regenerative medicine.

Sharma, Archana; Bhat, Sumrita; Vishnoi, Tanushree; Nayak, Vijayashree; Kumar, Ashok

2013-01-01

319

On nonnegative matrix factorization algorithms for signal-dependent noise with application to electromyography data.  

PubMed

Nonnegative matrix factorization (NMF) by the multiplicative updates algorithm is a powerful machine learning method for decomposing a high-dimensional nonnegative matrix V into two nonnegative matrices, W and H, where V ~ WH. It has been successfully applied in the analysis and interpretation of large-scale data arising in neuroscience, computational biology, and natural language processing, among other areas. A distinctive feature of NMF is its nonnegativity constraints that allow only additive linear combinations of the data, thus enabling it to learn parts that have distinct physical representations in reality. In this letter, we describe an information-theoretic approach to NMF for signal-dependent noise based on the generalized inverse gaussian model. Specifically, we propose three novel algorithms in this setting, each based on multiplicative updates, and prove monotonicity of updates using the EM algorithm. In addition, we develop algorithm-specific measures to evaluate their goodness of fit on data. Our methods are demonstrated using experimental data from electromyography studies, as well as simulated data in the extraction of muscle synergies, and compared with existing algorithms for signal-dependent noise. PMID:24684448

Devarajan, Karthik; Cheung, Vincent C K

2014-06-01

320

Finding Nonoverlapping Substructures of a Sparse Matrix  

SciTech Connect

Many applications of scientific computing rely on computations on sparse matrices. The design of efficient implementations of sparse matrix kernels is crucial for the overall efficiency of these applications. Due to the high compute-to-memory ratio and irregular memory access patterns, the performance of sparse matrix kernels is often far away from the peak performance on a modern processor. Alternative data structures have been proposed, which split the original matrix A into A{sub d} and A{sub s}, so that A{sub d} contains all dense blocks of a specified size in the matrix, and A{sub s} contains the remaining entries. This enables the use of dense matrix kernels on the entries of A{sub d} producing better memory performance. In this work, we study the problem of finding a maximum number of nonoverlapping dense blocks in a sparse matrix, which is previously not studied in the sparse matrix community. We show that the maximum nonoverlapping dense blocks problem is NP-complete by using a reduction from the maximum independent set problem on cubic planar graphs. We also propose a 2/3-approximation algorithm that runs in linear time in the number of nonzeros in the matrix. This extended abstract focuses on our results for 2x2 dense blocks. However we show that our results can be generalized to arbitrary sized dense blocks, and many other oriented substructures, which can be exploited to improve the memory performance of sparse matrix operations.

Pinar, Ali; Vassilevska, Virginia

2005-08-11

321

Pulse mode operation of Love wave devices for biosensing applications.  

PubMed

In this work we present a novel pulse mode Love wave biosensor that monitors both changes in amplitude and phase. A series of concentrations of 3350 molecular weight poly(ethylene glycol) (PEG) solutions are used as a calibration sequence for the pulse mode system using a network analyzer and high frequency oscilloscope. The operation of the pulse mode system is then compared to the continuous wave network analyzer by showing a sequence of deposition and removal of a model mass layer of palmitoyl-oleoyl-sn-glycerophosphocholine (POPC) vesicles. This experimental apparatus has the potential for making many hundreds of measurements a minute and so allowing the dynamics of fast interactions to be observed. PMID:11814185

Newton, M I; McHale, G; Martin, F; Gizeli, E; Melzak, K A

2001-12-01

322

Military applications of hypoxic training for high-altitude operations.  

PubMed

Rapid deployment of unacclimatized soldiers to high mountainous environments causes debilitating effects on operational capabilities (physical work performance), and force health (altitude sickness). Most of these altitude-induced debilitations can be prevented or ameliorated by a wide range of physiological responses collectively referred to as altitude acclimatization. Acclimatization to a target altitude can be induced by slow progressive ascents or continuous sojourns at intermediate altitudes. However, this "altitude residency" requirement reduces their utilization in rapid response military missions that exploit the air mobility capability of modern military forces to quickly deploy to an area of operations on short notice. A more recent approach to induce altitude acclimatization is the use of daily intermittent hypoxic exposures (IHE) in lieu of continuous residence at high altitudes. IHE treatments consist of three elements: 1) IHE simulated altitude (inspired oxygen partial pressure: PIO2), 2) IHE session duration, and 3) total number of IHE sessions over the treatment period. This paper reviews and summarizes the results of 25 published IHE studies. This review finds that an IHE altitude>or=4000 m, and daily exposure duration of at least 1.5 h repeated over a week or more are required to have a high probability of developing altitude acclimatization. The efficacy of shorter duration (<1.5 h) hypoxic exposures at >or=4000 m simulated altitudes, and longer exposures (>4 h) at moderate altitudes (2500-3500 m) is not well documented. The predominate IHE-induced altitude acclimatization response appears to be increased arterial oxygen content through ventilatory acclimatization. Thus, IHE is a promising approach to provide the benefits of altitude acclimatization to low-altitude-based soldiers before their deployment to high mountainous regions. PMID:17805096

Muza, Stephen R

2007-09-01

323

Development of RGB Composite Imagery for Operational Weather Forecasting Applications  

NASA Technical Reports Server (NTRS)

The NASA Short-term Prediction Research and Transition (SPoRT) Center, in collaboration with the Cooperative Institute for Research in the Atmosphere (CIRA), is providing red-green-blue (RGB) color composite imagery to several of NOAA s National Centers and National Weather Service forecast offices as a demonstration of future capabilities of the Advanced Baseline Imager (ABI) to be implemented aboard GOES-R. Forecasters rely upon geostationary satellite imagery to monitor conditions over their regions of responsibility. Since the ABI will provide nearly three times as many channels as the current GOES imager, the volume of data available for analysis will increase. RGB composite imagery can aid in the compression of large data volumes by combining information from multiple channels or paired channel differences into single products that communicate more information than provided by a single channel image. A standard suite of RGB imagery has been developed by the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT), based upon the Spinning Enhanced Visible and Infrared Imager (SEVIRI). The SEVIRI instrument currently provides visible and infrared wavelengths comparable to the future GOES-R ABI. In addition, the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments aboard the NASA Terra and Aqua satellites can be used to demonstrate future capabilities of GOES-R. This presentation will demonstrate an overview of the products currently disseminated to SPoRT partners within the GOES-R Proving Ground, and other National Weather Service forecast offices, along with examples of their application. For example, CIRA has used the channels of the current GOES sounder to produce an "air mass" RGB originally designed for SEVIRI. This provides hourly imagery over CONUS for looping applications while demonstrating capabilities similar to the future ABI instrument. SPoRT has developed similar "air mass" RGB imagery from MODIS, and through a case study example, synoptic-scale features evident in single-channel water vapor imagery are shown in the context of the air mass product. Other products, such as the "nighttime microphysics" RGB, are useful in the detection of low clouds and fog. Nighttime microphysics products from MODIS offer some advantages over single-channel or spectral difference techniques and will be discussed in the context of a case study. Finally, other RGB products from SEVIRI are being demonstrated as precursors to GOES-R within the GOES-R Proving Ground. Examples of "natural color" and "dust" imagery will be shown with relevant applications.

Molthan, Andrew L.; Fuell, Kevin K.; Oswald, Hayden, K; Knaff, John A.

2012-01-01

324

Maintenance, operation, and research (radiation) zones (MORZ) application model - a design and operation tool for intelligent buildings with application to the advanced neutron source.  

National Technical Information Service (NTIS)

This paper describes a user-friendly application tool to assist in the design, operation and maintenance of large buildings/facilities charged with complex/extensive/elaborate activities. The model centers around a specially designed, easy-access data bas...

H. B. Shapira R. A. Brown

1995-01-01

325

Development and characterization of starch nanoparticles by gamma radiation: potential application as starch matrix filler.  

PubMed

Gamma radiation arises as an advantageous alternative to obtain starch nanoparticles given its low cost, simple methodology and scalability. Starch nanoparticles (SNP) with sizes around 20 and 30 nm were obtained applying a dose of 20 kGy from cassava (CNP-?) and waxy maize (WNP-?) starch, respectively. They showed the same thermal degradation behavior and their maximum mass loss zone was similar to those nanoparticles obtained from acid hydrolysis (WNP-h). Additionally, CNP-? and WNP-? were used as nanofillers in a cassava matrix. Increments of 102% in storage modulus were obtained with the addition of only 2.5 wt.% of WNP-?, showing that gamma radiation is a successful methodology to obtain SNP able to be used as starch reinforcement. PMID:23769521

Lamanna, Melisa; Morales, Noé J; García, Nancy Lis; Goyanes, Silvia

2013-08-14

326

The application of Positive Matrix Factorization (PMF) to eco-efficiency analysis.  

PubMed

A new method for weighting and aggregating eco-efficiency indicators is of the utmost importance, if researchers in the field are to provide simplified and physically meaningful information to policy makers. To date, there is still considerable debate over which weighting and aggregating methods to use in this context. We apply a new variant of factor analysis, Positive Matrix Factorization (PMF), to a simple eco-efficiency analysis case study. PMF constrains its solutions to be non-negative, providing two important advantages over traditional factor analysis (FA) or principal component analysis (PCA): the rotational ambiguity of the solution space is reduced, and all the results are guaranteed to be physically meaningful. We suggest that PMF is better choice than either FA or PCA for eco-efficiency indicators, especially when dealing with complex social-economic and environmental data. PMID:22325638

Wu, Jiaying; Wu, Zhijun; Holländer, Robert

2012-05-15

327

Concerning an application of the method of least squares with a variable weight matrix  

NASA Technical Reports Server (NTRS)

An estimate of a state vector for a physical system when the weight matrix in the method of least squares is a function of this vector is considered. An iterative procedure is proposed for calculating the desired estimate. Conditions for the existence and uniqueness of the limit of this procedure are obtained, and a domain is found which contains the limit estimate. A second method for calculating the desired estimate which reduces to the solution of a system of algebraic equations is proposed. The question of applying Newton's method of tangents to solving the given system of algebraic equations is considered and conditions for the convergence of the modified Newton's method are obtained. Certain properties of the estimate obtained are presented together with an example.

Sukhanov, A. A.

1979-01-01

328

Application of neural networks in the acousto-ultrasonic evaluation of metal-matrix composite specimens  

NASA Technical Reports Server (NTRS)

Acousto-ultrasonics (AU) is a nondestructive evaluation (NDE) technique that was devised for the testing of various types of composite materials. A study has been done to determine how effectively the AU technique may be applied to metal-matrix composites (MMCs). The authors use the results and data obtained from that study and apply neural networks to them, particularly in the assessment of mechanical property variations of a specimen from AU measurements. It is assumed that there is no information concerning the important features of the AU signal which relate to the mechanical properties of the specimen. Minimally processed AU measurements are used while relying on the network's ability to extract the significant features of the signal.

Cios, Krzysztof J.; Tjia, Robert E.; Vary, Alex; Kautz, Harold E.

1992-01-01

329

Thermoplastic matrix composites for aeronautical applications - The amorphous/semi-crystalline blends option  

NASA Astrophysics Data System (ADS)

Blends obtained by mixing high temperature applications thermoplastics have been investigated. Namely the blends considered in this work are made by semi-crystalline thermoplastics PEEK with amorphous PEI. The final goal is to analyse the mechanical, chemical-physical and environmental resistance characteristics of these blends to evaluate their suitability as matrices of carbon reinforced composites for aeronautical structural applications. The first collected results are very promising.

Iannone, Michele; Esposito, Floriana; Cammarano, Aniello

2014-05-01

330

47 CFR 0.483 - Applications for amateur or commercial radio operator licenses.  

Code of Federal Regulations, 2013 CFR

...part 97 of this chapter. (b) Application filing procedures for commercial radio operator licenses are set forth in part 13 of this chapter. [47 FR 53378, Nov. 26, 1982, as amended at 78 FR 23151, Apr. 18,...

2013-10-01

331

Application of Light-Amplification Systems to Small Boats and Beach-Discharge Operations.  

National Technical Information Service (NTIS)

This report outlines procedures for ship-discharge operations on beaches under wartime conditions by the use of light-amplification equipment. Certain companion projects are incidental to this work and may have widespread applications. These include: Ligh...

P. Morrill

1968-01-01

332

Non-Lethal Weapons: MEF Application in Joint High Intensity Conflict Battle Field Operations.  

National Technical Information Service (NTIS)

The scope of this paper covers current and future NLW technology most likely to have an application in MEF high intensity battlefield operations. These principally include but are not limited to Chemical (Sleep Agents), Electro-Magnetic (Non Nuclear Elect...

J. R. Rizzo

1998-01-01

333

75 FR 33365 - Entergy Nuclear Operations, Inc.; Notice of Withdrawal of Application for Amendment to Facility...  

Federal Register 2010, 2011, 2012, 2013

...to withdraw its August 28, 2008, application for proposed amendment to Facility Operating License No. DPR-20 for the Palisades Nuclear Plant, located in Van Buren County, Michigan. The proposed amendment would have revised the facility...

2010-06-11

334

77 FR 2327 - Entergy Nuclear Operations, Inc.; Notice of Withdrawal of Application for Amendment to Facility...  

Federal Register 2010, 2011, 2012, 2013

...application for the proposed amendment to Renewed Facility Operating License (FOL) No. DPR-59 for the James A. FitzPatrick Nuclear Power Plant, located in Oswego County, New York. The proposed amendment would have modified the Renewed FOL...

2012-01-17

335

76 FR 37309 - Parts and Accessories Necessary for Safe Operation; Application for Exemption From the Natural...  

Federal Register 2010, 2011, 2012, 2013

...Application for Exemption From the Natural Gas Vehicles for America AGENCY: Federal...adopted safety standards specific to natural gas vehicles that do not restrict the...buses equipped with roof-mounted natural gas tanks operating in interstate...

2011-06-27

336

Verification of operating software for cooperative monitoring applications  

SciTech Connect

Monitoring agencies often use computer based equipment to control instruments and to collect data at sites that are being monitored under international safeguards or other cooperative monitoring agreements. In order for this data to be used as an independent verification of data supplied by the host at the facility, the software used must be trusted by the monitoring agency. The monitoring party must be sure that the software has not be altered to give results that could lead to erroneous conclusions about nuclear materials inventories or other operating conditions at the site. The host might also want to verify that the software being used is the software that has been previously inspected in order to be assured that only data that is allowed under the agreement is being collected. A description of a method to provide this verification using keyed has functions and how the proposed method overcomes possible vulnerabilities in methods currently in use such as loading the software from trusted disks is presented. The use of public key data authentication for this purpose is also discussed.

Tolk, K.M.; Rembold, R.K.

1997-08-01

337

Application, integration and operational aspects of an inertial navigation\\/survey\\/pointing system  

Microsoft Academic Search

The Modular Azimuth Position System, a ring-laser-gyro-based, inertial navigation, survey, and pointing system, is designed for military land vehicles. The application, integration, and operational deployment of a MAPS-type inertial system are described. Detailed aspects of operational use for a variety of applications are explored, including positioning of artillery howitzers, missile launchers, and battlefield surveillance vehicles; the pointing of weapons on

Michael J. Hadfield; Kenneth E. Leiser

1989-01-01

338

Application-Specific Service Technologies for Commodity Operating Systems in Real-Time Environments  

Microsoft Academic Search

In order to eliminate the costs of proprietary systems and special purpose hardware, many real-time and em- bedded computing platforms are being built on commod- ity operating systems and generic hardware. Unfortunately, many such systems are ill-suited to the low-latency and predictable timing requirements of real-time applications. This paper, therefore, focuses on application-specific ser- vice technologies for low-cost commodity operating

Richard West; Gabriel Parmer

2006-01-01

339

A matrix lower bound  

SciTech Connect

A matrix lower bound is defined that generalizes ideas apparently due to S. Banach and J. von Neumann. The matrix lower bound has a natural interpretation in functional analysis, and it satisfies many of the properties that von Neumann stated for it in a restricted case. Applications for the matrix lower bound are demonstrated in several areas. In linear algebra, the matrix lower bound of a full rank matrix equals the distance to the set of rank-deficient matrices. In numerical analysis, the ratio of the matrix norm to the matrix lower bound is a condition number for all consistent systems of linear equations. In optimization theory, the matrix lower bound suggests an identity for a class of min-max problems. In real analysis, a recursive construction that depends on the matrix lower bound shows that the level sets of continuously differential functions lie asymptotically near those of their tangents.

Grcar, Joseph F.

2002-02-04

340

A Mission Management Application Suite for Airborne Science Operations  

NASA Astrophysics Data System (ADS)

Collection of data during airborne field campaigns is a critically important endeavor. It is imperative to observe the correct phenomena at the right time - at the right place to maximize the instrument observations. Researchers at NASA Marshall Space Flight Center have developed an application suite known as the Real Time Mission Monitor (RTMM). This suite is comprised of tools for mission design, flight planning, aircraft visualization and tracking. The mission design tool allows scientists to set mission parameters such as geographic boundaries and dates of the campaign. Based on these criteria, the tool intelligently selects potential data sets from a data resources catalog from which the scientist is able to choose the aircraft, instruments, and ancillary Earth science data sets to be provided for use in the remaining tool suite. The scientists can easily reconfigure and add data sets of their choosing for use during the campaign. The flight planning tool permits the scientist to assemble aircraft flight plans and to plan coincident observations with other aircraft, spacecraft or in situ observations. Satellite and ground-based remote sensing data and modeling data are used as background layers to aid the scientist in the flight planning process. Planning is crucial to successful collection of data and the ability to modify the plan and upload to aircraft navigators and pilots is essential for the agile collection of data. Most critical to successful and cost effective collection of data is the capability to visualize the Earth science data (airborne instruments, radiosondes, radar, dropsondes, etc.) and track the aircraft in real time. In some instances, aircraft instrument data is provided to ground support personnel in near-real time to visualize with the flight track. This visualization and tracking aspect of RTMM provides a decision support capability in conjunction with scientific collaboration portals to allow for scientists on the ground to communicate most effectively with scientists aboard the aircraft to achieve successful observations.

Goodman, H. M.; Meyer, P. J.; Blakeslee, R.; Regner, K.; Hall, J.; He, M.; Conover, H.; Garrett, M.; Harper, J.; Smith, T.; Grewe, A.; Real Time Mission Monitor Team

2011-12-01

341

The Iron Project and the RmaX Project: R-Matrix Data for Astrophysical and Fusion Applications  

SciTech Connect

The R-Matrix method has long been employed to compute fundamental atomic parameters with high precision for large scale applications to astrophysical sources and magnetic and inertial fusion devices. Ongoing work is part of two projects: The Iron Project that focuses on Fe-peak elements, and the RmaX Project aimed at spectral diagnostics of laboratory and astrophysical X-ray plasmas. The primary atomic processes include electron impact excitation, photoionization, (e + ion) recombination, and spectral transitions. These data are employed in numerical simulations of high-temperature plasmas under stationary and transient conditions. The calculated parameters have been benchmarked against sophisticated experiments on electron-beam-ion-traps for excitation, synchrotron based light sources for photoionization, and heavy ion storage rings for (e + ion) recombination. Extensions of the two projects include a self-consistent and unified theoretical treatment of (e + ion) recombination that subsumes both the radiative and the dielectronic recombination processes. Cross sections are computed using an identical (e + ion) wavefunction expansion for both the photoionization and the recombination processes, thereby considering the resonant and non-resonant phenomena in an ab initio manner. Comparison with experiments ascertain an accuracy of 10-20%, within the uncertainties in experiment and theory, indicating that there are no significant shortcomings in the R-matrix method. We compare the close coupling R-matrix data with the Distorted Wave approximation and the effect on X-ray spectral analysis. Finally, we describe the electronic database TIPTOPbase, which will also make available new stellar opacities and radiative accelerations from the Opacity Project.

Pradhan, Anil K. [Ohio State University (United States)

2005-05-27

342

Application of matrix analysis in delineating sinkhole risk areas along highway (I-70 near Frederick, Maryland)  

Microsoft Academic Search

Sinkhole collapse in the area of Maryland Interstate 70 (I-70) and nearby roadways south of Frederick, Maryland, has been posing a threat to the safety of the highway operation as well as other structures. The occurrence of sinkholes is associated with intensive land development. However, the geological conditions that have been developing over the past 200 million years in the

Wanfang Zhou; Barry F. Beck; Angela L. Adams

2003-01-01

343

SVGA and XGA active matrix microdisplays for head-mounted applications  

Microsoft Academic Search

The MicroDisplay Corporation's liquid crystal on silicon (LCOS) display devices are based on the union of several technologies with the extreme integration capability of conventionally fabricated CMOS substrates. The fast liquid crystal operation modes and new scalable high-performance pixel addressing architectures presented in this paper enable substantially improved color, contrast, and brightness while still satisfying the optical, packaging, and power

Phillip Alvelda; Michael Bolotski; Imani L. Brown

2000-01-01

344

A study of the economics, operations and applications of SONET self-healing ring architectures  

Microsoft Academic Search

The economics, operations, and applications of synchronous optical network (SONET) unidirectional and bidirectional self-healing ring architectures are studied in order to ascertain whether the use of the two different types of ring architecture for SONET networks is advisable, both from an economic and operations viewpoint. It is shown that there are economic advantages to using both types of rings in

Joseph Sosnosky; Tsong-Ho Wu; Dorothy L. Alt

1991-01-01

345

Applying SWOT Analysis in Formulation of Propositions for more Effective Operational Application of Timeshare in Greece  

Microsoft Academic Search

The present paper aims to suggest specific actions- proposals for policies likely to counteract the difficulties involved in the operational application of Timeshare in Greece. The choice of the S.W.O.T. Analysis methodology can be accounted for by the fact that it enables the detection of strengths and weaknesses as they manifest themselves in the internal operational environment of the Greek

Theodoros Stavrinoudis

2007-01-01

346

Modular Forms and Second Order Ordinary Differential Equations: Applications to Vertex Operator Algebras  

NASA Astrophysics Data System (ADS)

We study the relation between the Kaneko-Zagier equation and the Mathur-Mukhi-Sen classification, and extend it to the case of solutions with logarithmic terms, which correspond to pseudo-characters of non-rational vertex operator algebras. As an application, we prove a non-existence theorem of rational vertex operator algebras.

Kaneko, Masanobu; Nagatomo, Kiyokazu; Sakai, Yuichi

2013-04-01

347

Influence of hydro-climatic conditions, soil type, and application matrix on potential vadose zone export of PPCPs  

NASA Astrophysics Data System (ADS)

The land-application of biosolids and animal manure to agricultural fields has the potential to negatively impact the quality of nearby surface and subsurface water due to the presence of emerging contaminants in these residuals. We investigated the extent to which the vadose zone acts as a hydrologic and biogeochemical filter of two emerging contaminants, Triclosan (TCS) and estrone (E1) using a coupled source zone and vadose zone modeling approach. Monte Carlo simulations were run for a year following residual applications to explore the following research questions: (1) how does the application matrix (e.g., de-watered solids, liquid lagoon effluent, etc.) affect PPCP mass fluxes?; (2) how do hydro-climatic conditions and soil type affect PPCP mass fluxes?; (3) what role does the presence of macropore pathways play in PPCP export from the vadose zone; and (4) does the long-term, repeated application of residuals affect the ability of the vadose zone to act as an effective biogeochemical filter? The simulations were conducted for a sub-tropical climate with sand (e.g., Florida) and a humid climate with a silty clay loam (e.g., Midwestern United States). Simulation results suggest that the potential mobility of emerging contaminants increases linearly with increasing fraction applied to the mobile phase of the source zone (i.e., higher PPCP mass fraction in the dissolved phase during application). Following a single application, the total amount of PPCP mass exported from the source zone over the course of a year can be as high as 70% in a sub-tropical climate with sand soil. However, these types of soils do not have macropore flow pathways and the annual PPCP mass exported from the vadose zone is less than 1% of the mass applied. The higher organic carbon content in a silty clay loam reduces the amount of PPCP mass released from the source zone to less than 5% of the mass applied. In the presence of macropore pathways, the silty clay loam's vadose zone acts as a less effective biogeochemical filter than the sand's vadose zone. However, following a single application, Monte Carlo simulations suggest that the annual mass exported from the silty clay loam's vadose zone is less than 0.2% of the applied mass. Additionally, simulation results suggest that the mass exported from the vadose zone of the silty clay loam increases with time when fields receive long-term, repeated residual applications. Thus, field studies conducted with single applications likely underestimate mass fluxes exported from fields with a history of applications.

Gall, H. E.; Rao, P.; O'Connor, G.

2013-12-01

348

40 CFR Table 1 to Subpart Vvvvvv... - Hazardous Air Pollutants Used To Determine Applicability of Chemical Manufacturing Operations  

Code of Federal Regulations, 2013 CFR

...Determine Applicability of Chemical Manufacturing Operations 1 Table 1 to Subpart...Hazardous Air Pollutants for Chemical Manufacturing Area Sources Pt. 63, Subpt. VVVVVV...Determine Applicability of Chemical Manufacturing Operations As required in §...

2013-07-01

349

Performance assessments of Android-powered military applications operating on tactical handheld devices  

NASA Astrophysics Data System (ADS)

Transformative Apps (TransApps) is a Defense Advanced Research Projects Agency (DARPA) funded program whose goal is to develop a range of militarily-relevant software applications ("apps") to enhance the operational-effectiveness of military personnel on (and off) the battlefield. TransApps is also developing a military apps marketplace to facilitate rapid development and dissemination of applications to address user needs by connecting engaged communities of endusers with development groups. The National Institute of Standards and Technology's (NIST) role in the TransApps program is to design and implement evaluation procedures to assess the performance of: 1) the various software applications, 2) software-hardware interactions, and 3) the supporting online application marketplace. Specifically, NIST is responsible for evaluating 50+ tactically-relevant applications operating on numerous Android™-powered platforms. NIST efforts include functional regression testing and quantitative performance testing. This paper discusses the evaluation methodologies employed to assess the performance of three key program elements: 1) handheld-based applications and their integration with various hardware platforms, 2) client-based applications and 3) network technologies operating on both the handheld and client systems along with their integration into the application marketplace. Handheld-based applications are assessed using a combination of utility and usability-based checklists and quantitative performance tests. Client-based applications are assessed to replicate current overseas disconnected (i.e. no network connectivity between handhelds) operations and to assess connected operations envisioned for later use. Finally, networked applications are assessed on handhelds to establish baselines of performance for when connectivity will be common usage.

Weiss, Brian A.; Fronczek, Lisa; Morse, Emile; Kootbally, Zeid; Schlenoff, Craig

2013-05-01

350

Application of electromagnetic environment simulation to radar performance testing, operability assessment and training  

NASA Astrophysics Data System (ADS)

Automatic target detection and tracking features in radar sensors affect the testing and evaluation of radar performance, the assessment of equipment readiness for verification of sensor, command/control and engagement systems' operability, and operational training of radar operators and sensor management teams. Attention is presently given to Radar Environment Simulator Systems (RESSs), which facilitate the interjection of testing and training scenarios into the front end of radar receivers. RESSs are applicable to shipboard, air, and ground environments.

Michaels, J. F.

351

Tailoring nanorod alignment in a polymer matrix by elongational flow under confinement: simulation, experiments, and surface enhanced Raman scattering application.  

PubMed

Mesoscale simulation, electrospinning and Raman scattering experiments have been carried out to demonstrate that examination and control of nanorod configuration in a polymer matrix under elongational flow and confinement can lead to enhanced sensing. First, coarse-grained molecular dynamics (CGMD) was employed to probe the diffusivity, orientation, and dispersion of nanorods in a model polymer melt under planar elongational flow. Compared to shear flow, elongational flow gives rise to enhanced dispersion and orientation of nanorods, which are predicted to be improved with increasing the aspect ratio of nanorods and polymer chain length. As comparative experiments, we have electrospun gold (Au) nanorods with polyvinyl alcohol (PVA), and the resulting Au nanorod configuration in PVA nanofibers is in good agreement with the predicted simulation. Furthermore, coaxial electrospinning of Au nanorod/PVA-PVA (shell-core) was applied to selectively place Au nanorods in the cylindrical sheath layer, and the alignment of Au nanorods near the fiber surface was confirmed by TEM analysis and CGMD simulation under uniaxial elongation. Finally, the Au nanorod-PVA fibers were tested for surface-enhanced Raman spectroscopy for sensing applications. The coaxially electrospun fibers have demonstrated much greater signal peak strength when compared with monoaxially electrospun fibers with the same Au nanorod loading. This comprehensive study demonstrates how extensional flow and multi-layered fluids can direct the orientation and dispersion of nanorod in a polymer matrix, leading to enhanced sensing performance. PMID:24652583

Park, Jay Hoon; Joo, Yong Lak

2014-05-21

352

Application of matrix solid-phase dispersion and high-performance liquid chromatography for determination of sulfonamides in honey.  

PubMed

A novel method for simultaneous determination of 8 sulfonamide residues (sulfathiazole, sulfapyridine, sulfadiazine, sulfamerazine, sulfamonome-thoxine, sulfachloropyridazine, sulfamethoxazole, and sulfadimethoxine) in honey samples by high-performance liquid chromatography (HPLC) has been developed on the basis of precolumn derivatization with 9-fluorenylmethyl-chloroformate (FMOC-Cl). Sulfonamide residues in honey samples were extracted and purified by matrix solid-phase dispersion with C18 as the solid support. The residues were derivatized by FMOC-CI, and the FMOC-sulfonamide derivatives were further purified by solid-phase extraction with silica gel as the solid support prior to HPLC analysis. The average recoveries for most sulfonamide compounds at different spiking levels (from 10 to 250 microg/kg) were > 70% with relative standard deviations < 16%, and their limits of detection were 4.0 microg/kg. The established analytical method has high sensitivity and repeatability and can be applicable for determining the sulfonamide residues in various honey matrixes. PMID:18376605

Zou, Qiong-Hui; Wang, Jin; Wang, Xiang-Feng; Liu, Yuan; Han, Jie; Hou, Feier; Xie, Meng-Xia

2008-01-01

353

Towards a theory of management and evaluation of operational enterprise resource planning applications  

Microsoft Academic Search

Enterprise resource planning (ERP) applications are the most ubiquitous of business information systems. They impact almost all business functions, bringing control and providing information. Some of these applications have already been operational for 20 years and this longevity has changed the way in which management of information systems is envisaged. Traditionally, information systems had a lifespan of perhaps five to

Richard Fulford

2008-01-01

354

Potential applications of expert systems and operations research to space station logistics functions  

NASA Technical Reports Server (NTRS)

The applicability of operations research, artificial intelligence, and expert systems to logistics problems for the space station were assessed. Promising application areas were identified for space station logistics. A needs assessment is presented and a specific course of action in each area is suggested.

Lippiatt, Thomas F.; Waterman, Donald

1985-01-01

355

The impact of operating system scheduling policies and synchronization methods of performance of parallel applications  

Microsoft Academic Search

Shared-memory multiprocessors are frequently used as compute servers with multiple parallel applications executing at the same time. In such environments, the efficiency of a parallel application can be significantly affected by the operating system scheduling policy. In this paper, we use detailed simulation studies to evaluate the performance of several different scheduling strategies, These include regular priority scheduling, coscheduling or

Anoop Gupta; Andrew Tucker; Shigeru Urushibara

1991-01-01

356

Automatic generation and targeting of application specific operating systems and embedded systems software  

Microsoft Academic Search

We propose a method of automatic generation of appli- cation specific operating systems (OS's) and automatic tar- geting of application software. OS generation starts from a very small but yet flexible OS kernel. OS services, which are specific to the application and deduced from dependencies between services, are added to the kernel to construct the whole OS. Communication and synchronization

L. Guthier; Sungjoo Yoo; Ahmed Amine Jerraya

2001-01-01

357

The Case for a Secure Multi-Application Smart Card Operating System  

Microsoft Academic Search

The idea of a multi-application smart card operating system is not a new one, but only recently the smart card industry is catching up with proper software and hardware architectures that contribute in the anticipated evolution. In this paper we survey some of the proposed software architectures and comment on their applicability and performance, along with investigating the entirely new

Constantinos Markantonakis

1997-01-01

358

A Public Safety Application of GPS-Enabled Smartphones and the Android Operating System  

Microsoft Academic Search

While the Apple iPhone single handedly redefined the term ¿smartphone¿ during its first two years of release, Google's Android platform for mobile devices has quickly developed into a serious open source alternative. We explored the android operating system (OS) and software development environment and evaluated several of its capabilities by constructing a working application. This application collected speed and location

William L. Arensman; John G. Whipple; Marian Starr Boler

2009-01-01

359

Review article: Polymer-matrix Nanocomposites, Processing, Manufacturing, and Application: An Overview  

Microsoft Academic Search

This review is designed to be a comprehensive source for polymer nanocomposite research, including fundamental structure\\/property relationships, manufacturing techniques, and applications of polymer nanocomposite materials. In addition to presenting the scientific framework for the advances in polymer nanocomposite research, this review focuses on the scientific principles and mechanisms in relation to the methods of processing and manufacturing with a discussion

Farzana Hussain; Mehdi Hojjati; Masami Okamoto; Russell E. Gorga

2006-01-01

360

Identification of Bicluster Regions in a Binary Matrix and Its Applications  

PubMed Central

Biclustering has emerged as an important approach to the analysis of large-scale datasets. A biclustering technique identifies a subset of rows that exhibit similar patterns on a subset of columns in a data matrix. Many biclustering methods have been proposed, and most, if not all, algorithms are developed to detect regions of “coherence” patterns. These methods perform unsatisfactorily if the purpose is to identify biclusters of a constant level. This paper presents a two-step biclustering method to identify constant level biclusters for binary or quantitative data. This algorithm identifies the maximal dimensional submatrix such that the proportion of non-signals is less than a pre-specified tolerance ?. The proposed method has much higher sensitivity and slightly lower specificity than several prominent biclustering methods from the analysis of two synthetic datasets. It was further compared with the Bimax method for two real datasets. The proposed method was shown to perform the most robust in terms of sensitivity, number of biclusters and number of serotype-specific biclusters identified. However, dichotomization using different signal level thresholds usually leads to different sets of biclusters; this also occurs in the present analysis.

Chen, Hung-Chia; Zou, Wen; Tien, Yin-Jing; Chen, James J.

2013-01-01

361

Use of the Covariance Matrix in Directly Fitting Kinetic Parameters: Application to GABAA Receptors  

PubMed Central

A new method of analysis is described that begins to explore the relationship between the phases of ion channel desensitization and the underlying states of the channel. The method, referred to as covariance fitting (CVF), couples Q-matrix calculations with a maximum likelihood algorithm to fit macroscopic desensitization data directly to kinetic models. Unlike conventional sum-of-squares minimization, CVF fits both the magnitude of the recorded current and the strength of the correlations between different time points. When applied to simulated data generated using various kinetic models with up to 11 free parameters, CVF leads to reasonable parameter estimates. Coupled with the likelihood ratio test, it accurately discriminates between models with different numbers of states, discriminates between most models with the same number but a different arrangement of states, and extracts meaningful information on the relationship between the desensitized states and the phases of macroscopic desensitization. When applied to GABAA receptor traces (outside out patches, ?1?2?2S, 1 mM GABA, >2.5 s), a model with two open states and three desensitized states is favored. When applied to simulated data generated using a consensus model, CVF leads to reasonable parameter estimates and accurately discriminates between this and other models.

Celentano, James J.; Hawkes, Alan G.

2004-01-01

362

Ceramic fibers for matrix composites in high-temperature engine applications  

PubMed

High-temperature engine applications have been limited by the performance of metal alloys and carbide fiber composites at elevated temperatures. Random inorganic networks composed of silicon, boron, nitrogen, and carbon represent a novel class of ceramics with outstanding durability at elevated temperatures. SiBN(3)C was synthesized by pyrolysis of a preceramic N-methylpolyborosilazane made from the single-source precursor Cl(3)Si-NH-BCl(2). The polymer can be processed to a green fiber by melt-spinning, which then undergoes an intermediate curing step and successive pyrolysis. The ceramic fibers, which are presently produced on a semitechnical scale, combine several desired properties relevant for an application in fiber-reinforced ceramic composites: thermal stability, mechanical strength, high-temperature creep resistivity, low density, and stability against oxidation or molten silicon. PMID:10426985

Baldus; Jansen; Sporn

1999-07-30

363

Analytic system matrix resolution modeling in PET: an application to Rb82 cardiac imaging  

Microsoft Academic Search

This work explores application of a novel resolution modeling technique based on analytic physical models which individually models the various resolution degrading effects in PET (positron range, photon non-collinearity, inter-crystal scattering and inter-crystal penetration) followed by their combination and incorporation within the image reconstruction task. In addition to phantom studies, the proposed technique was particularly applied to and studied in

A. Rahmim; J. Tang; M. A. Lodge; S. Lashkari; M. R. Ay; R. Lautamäki; B. M. W. Tsui; F. M. Bengel

2008-01-01

364

The application of optical coherence tomography to problems in polymer matrix composites  

NASA Astrophysics Data System (ADS)

The Composites Group at the National Institute of Standards and Technology has found optical coherence tomography (OCT) to be a powerful tool for non-destructive characterization of polymer matrix composites. Composites often exhibit superior properties to traditional materials such as wood and metal. However, the barrier to their widespread infiltration into consumer markets is cost. Composites can be made more cost competitive by improved composite design, process optimization, and quality control. OCT provides a means of evaluating the three aforementioned areas. OCT is a very versatile technique that can be applied to a variety of problems in polymer composites such as: microstructure determination for permeability and mechanical property prediction, void, dry spot, and defect detection, and damage evaluation. Briefly, OCT uses a low coherence source such as a superluminescent diode laser with a fiber optic based Michelson interferometer. In this configuration, the composite is the fixed arm of the interferometer. Reflections from heterogeneities within the sample are mapped as a function of thickness for any one position. Volume information is generated by translating the sample on a motorized stage. Information about the location and size of a feature within the composite is obtained. In this work, the power of OCT for imaging composite microstructure and damage is presented. An example of permeability prediction using the composite microstructure imaged from OCT is demonstrated. The effect of image processing on the value of permeability is discussed. Using the same sample, OCT imaging of composite impact damage is compared to more traditional techniques, X-ray computed tomography and confocal microscopy.

Dunkers, Joy P.; Phelan, Frederick R.; Sanders, Daniel P.; Everett, Matthew J.; Green, William H.; Hunston, Donald L.; Parnas, Richard S.

365

Advanced ceramic matrix composite materials for current and future propulsion technology applications  

NASA Astrophysics Data System (ADS)

Current rocket engines, due to their method of construction, the materials used and the extreme loads to which they are subjected, feature a limited number of load cycles. Various technology programmes in Europe are concerned, besides developing reliable and rugged, low cost, throwaway equipment, with preparing for future reusable propulsion technologies. One of the key roles for realizing reusable engine components is the use of modern and innovative materials. One of the key technologies which concern various engine manufacturers worldwide is the development of fibre-reinforced ceramics—ceramic matrix composites. The advantages for the developers are obvious—the low specific weight, the high specific strength over a large temperature range, and their great damage tolerance compared to monolithic ceramics make this material class extremely interesting as a construction material. Over the past years, the Astrium company (formerly DASA) has, together with various partners, worked intensively on developing components for hypersonic engines and liquid rocket propulsion systems. In the year 2000, various hot-firing tests with subscale (scale 1:5) and full-scale nozzle extensions were conducted. In this year, a further decisive milestone was achieved in the sector of small thrusters, and long-term tests served to demonstrate the extraordinary stability of the C/SiC material. Besides developing and testing radiation-cooled nozzle components and small-thruster combustion chambers, Astrium worked on the preliminary development of actively cooled structures for future reusable propulsion systems. In order to get one step nearer to this objective, the development of a new fibre composite was commenced within the framework of a regionally sponsored programme. The objective here is to create multidirectional (3D) textile structures combined with a cost-effective infiltration process. Besides material and process development, the project also encompasses the development of special metal/ceramic and ceramic/ceramic joining techniques as well as studying and verifying non destructive investigation processes for the purpose of testing components.

Schmidt, S.; Beyer, S.; Knabe, H.; Immich, H.; Meistring, R.; Gessler, A.

2004-08-01

366

Application of Reduced Order Transonic Aerodynamic Influence Coefficient Matrix for Design Optimization  

NASA Technical Reports Server (NTRS)

Supporting the Aeronautics Research Mission Directorate guidelines, the National Aeronautics and Space Administration [NASA] Dryden Flight Research Center is developing a multidisciplinary design, analysis, and optimization [MDAO] tool. This tool will leverage existing tools and practices, and allow the easy integration and adoption of new state-of-the-art software. Today s modern aircraft designs in transonic speed are a challenging task due to the computation time required for the unsteady aeroelastic analysis using a Computational Fluid Dynamics [CFD] code. Design approaches in this speed regime are mainly based on the manual trial and error. Because of the time required for unsteady CFD computations in time-domain, this will considerably slow down the whole design process. These analyses are usually performed repeatedly to optimize the final design. As a result, there is considerable motivation to be able to perform aeroelastic calculations more quickly and inexpensively. This paper will describe the development of unsteady transonic aeroelastic design methodology for design optimization using reduced modeling method and unsteady aerodynamic approximation. The method requires the unsteady transonic aerodynamics be represented in the frequency or Laplace domain. Dynamically linear assumption is used for creating Aerodynamic Influence Coefficient [AIC] matrices in transonic speed regime. Unsteady CFD computations are needed for the important columns of an AIC matrix which corresponded to the primary modes for the flutter. Order reduction techniques, such as Guyan reduction and improved reduction system, are used to reduce the size of problem transonic flutter can be found by the classic methods, such as Rational function approximation, p-k, p, root-locus etc. Such a methodology could be incorporated into MDAO tool for design optimization at a reasonable computational cost. The proposed technique is verified using the Aerostructures Test Wing 2 actually designed, built, and tested at NASA Dryden Flight Research Center. The results from the full order model and the approximate reduced order model are analyzed and compared.

Pak, Chan-gi; Li, Wesley W.

2009-01-01

367

Nonnegative matrix factorization with the Itakura-Saito divergence: with application to music analysis.  

PubMed

This letter presents theoretical, algorithmic, and experimental results about nonnegative matrix factorization (NMF) with the Itakura-Saito (IS) divergence. We describe how IS-NMF is underlaid by a well-defined statistical model of superimposed gaussian components and is equivalent to maximum likelihood estimation of variance parameters. This setting can accommodate regularization constraints on the factors through Bayesian priors. In particular, inverse-gamma and gamma Markov chain priors are considered in this work. Estimation can be carried out using a space-alternating generalized expectation-maximization (SAGE) algorithm; this leads to a novel type of NMF algorithm, whose convergence to a stationary point of the IS cost function is guaranteed. We also discuss the links between the IS divergence and other cost functions used in NMF, in particular, the Euclidean distance and the generalized Kullback-Leibler (KL) divergence. As such, we describe how IS-NMF can also be performed using a gradient multiplicative algorithm (a standard algorithm structure in NMF) whose convergence is observed in practice, though not proven. Finally, we report a furnished experimental comparative study of Euclidean-NMF, KL-NMF, and IS-NMF algorithms applied to the power spectrogram of a short piano sequence recorded in real conditions, with various initializations and model orders. Then we show how IS-NMF can successfully be employed for denoising and upmix (mono to stereo conversion) of an original piece of early jazz music. These experiments indicate that IS-NMF correctly captures the semantics of audio and is better suited to the representation of music signals than NMF with the usual Euclidean and KL costs. PMID:18785855

Févotte, Cédric; Bertin, Nancy; Durrieu, Jean-Louis

2009-03-01

368

Wrapper-based selection of genetic features in genome-wide association studies through fast matrix operations  

PubMed Central

Background Through the wealth of information contained within them, genome-wide association studies (GWAS) have the potential to provide researchers with a systematic means of associating genetic variants with a wide variety of disease phenotypes. Due to the limitations of approaches that have analyzed single variants one at a time, it has been proposed that the genetic basis of these disorders could be determined through detailed analysis of the genetic variants themselves and in conjunction with one another. The construction of models that account for these subsets of variants requires methodologies that generate predictions based on the total risk of a particular group of polymorphisms. However, due to the excessive number of variants, constructing these types of models has so far been computationally infeasible. Results We have implemented an algorithm, known as greedy RLS, that we use to perform the first known wrapper-based feature selection on the genome-wide level. The running time of greedy RLS grows linearly in the number of training examples, the number of features in the original data set, and the number of selected features. This speed is achieved through computational short-cuts based on matrix calculus. Since the memory consumption in present-day computers can form an even tighter bottleneck than running time, we also developed a space efficient variation of greedy RLS which trades running time for memory. These approaches are then compared to traditional wrapper-based feature selection implementations based on support vector machines (SVM) to reveal the relative speed-up and to assess the feasibility of the new algorithm. As a proof of concept, we apply greedy RLS to the Hypertension – UK National Blood Service WTCCC dataset and select the most predictive variants using 3-fold external cross-validation in less than 26 minutes on a high-end desktop. On this dataset, we also show that greedy RLS has a better classification performance on independent test data than a classifier trained using features selected by a statistical p-value-based filter, which is currently the most popular approach for constructing predictive models in GWAS. Conclusions Greedy RLS is the first known implementation of a machine learning based method with the capability to conduct a wrapper-based feature selection on an entire GWAS containing several thousand examples and over 400,000 variants. In our experiments, greedy RLS selected a highly predictive subset of genetic variants in a fraction of the time spent by wrapper-based selection methods used together with SVM classifiers. The proposed algorithms are freely available as part of the RLScore software library at http://users.utu.fi/aatapa/RLScore/.

2012-01-01

369

Forward operation of adenine nucleotide translocase during F0F1-ATPase reversal: critical role of matrix substrate-level phosphorylation  

PubMed Central

In pathological conditions, F0F1-ATPase hydrolyzes ATP in an attempt to maintain mitochondrial membrane potential. Using thermodynamic assumptions and computer modeling, we established that mitochondrial membrane potential can be more negative than the reversal potential of the adenine nucleotide translocase (ANT) but more positive than that of the F0F1-ATPase. Experiments on isolated mitochondria demonstrated that, when the electron transport chain is compromised, the F0F1-ATPase reverses, and the membrane potential is maintained as long as matrix substrate-level phosphorylation is functional, without a concomitant reversal of the ANT. Consistently, no cytosolic ATP consumption was observed using plasmalemmal KATP channels as cytosolic ATP biosensors in cultured neurons, in which their in situ mitochondria were compromised by respiratory chain inhibitors. This finding was further corroborated by quantitative measurements of mitochondrial membrane potential, oxygen consumption, and extracellular acidification rates, indicating nonreversal of ANT of compromised in situ neuronal and astrocytic mitochondria; and by bioluminescence ATP measurements in COS-7 cells transfected with cytosolic- or nuclear-targeted luciferases and treated with mitochondrial respiratory chain inhibitors in the presence of glycolytic plus mitochondrial vs. only mitochondrial substrates. Our findings imply the possibility of a rescue mechanism that is protecting against cytosolic/nuclear ATP depletion under pathological conditions involving impaired respiration. This mechanism comes into play when mitochondria respire on substrates that support matrix substrate-level phosphorylation.—Chinopoulos, C., Gerencser, A. A., Mandi, M., Mathe, K., Töröcsik, B., Doczi, J., Turiak, L., Kiss, G., Konràd, C., Vajda, S., Vereczki, V., Oh, R. J., Adam-Vizi, V. Forward operation of adenine nucleotide translocase during F0F1-ATPase reversal: critical role of matrix substrate-level phosphorylation.

Chinopoulos, Christos; Gerencser, Akos A.; Mandi, Miklos; Mathe, Katalin; Torocsik, Beata; Doczi, Judit; Turiak, Lilla; Kiss, Gergely; Konrad, Csaba; Vajda, Szilvia; Vereczki, Viktoria; Oh, Richard J.; Adam-Vizi, Vera

2010-01-01

370

Processing, compatibility and oxidation of diboride-reinforced oxide matrix composites for ultrahigh-temperature applications  

SciTech Connect

Promising results for the development of a ceramic/ceramic composite to be used for structural applications in the ultra high temperature range (1650 to 1850 C) were obtained for alumina reinforced with titanium or zirconium diboride coated with molybdenum disilicide. Calculations of the compatibility and stability of oxide matrices with the diborides in vacuum showed positive energies of formation, indicating suitability of reinforcement of alumina under vacuum conditions. Stability and chemical compatibility of the particulate and ternary composites in their as hot pressed states and following their vacuum and air oxidation treatment were characterized.

Abada, A.

1990-01-01

371

Electrically conductive, black thermal control coatings for spacecraft application. I - Silicate matrix formulation  

NASA Technical Reports Server (NTRS)

The formulation of the graphite silicate paints MH-11 and MH-11Z, which will serve as electrically conductive, heat-resistant thermal control coatings for the Galileo spacecraft's 400 Newton engine plume shield, 10 Newton thruster plume shields, and external shunt radiators, is described, and performance results for these paints are reported. The MH-11 is produced by combining a certain grade of graphite powder with a silicate base to produce a black, inorganic, electrically conductive, room temperature cure thermal control paint having high temperature capability. Zinc oxide is added to the MH-11 formulation to produce the blister resistant painta MH-11Z. The mechanical, chemical, thermal, optical, and radiation characteristics of the coatings are reported. The formulation, mixing, application, and surface preparation of the substrates are described, and a method of determining the electrical resistance of the coatings is demonstrated.

Bauer, J. L.; Odonnell, T. P.; Hribar, V. F.

1986-01-01

372

Matrix diagonalization algorithm and its applicability to the nuclear shell model  

SciTech Connect

An importance-sampling iterative algorithm for diagonalizing shell model Hamiltonian matrices is reviewed and implemented in a spin uncoupled basis. Shell model spaces of dimensions up to N < or approx.10{sup 9} are considered. The analysis shows that about 10% of the basis states are enough to bring the eigenvalues to convergence. This fraction of states, however, is insufficient to lead to convergence of the transition strengths, thereby limiting the applicability of the method to not too large spaces. In its domain of validity, the method yields a large number of eigensolutions and can be usefully adopted for rather complete studies of low-energy spectroscopy. This is done here for {sup 132,134}Xe isotopes. The calculation yields spectra and electromagnetic responses in fairly good agreement with the available experimental data and unveils the properties of the low-energy states of these isotopes, including their proton-neutron symmetry.

Bianco, D.; Andreozzi, F.; Lo Iudice, N.; Porrino, A.; Knapp, F. [Dipartimento di Scienze Fisiche, Universita di Napoli Federico II and Istituto Nazionale di Fisica Nucleare, Monte S. Angelo, via Cintia, I-80126 Napoli (Italy)

2011-08-15

373

Dynamic uncertain causality graph for knowledge representation and probabilistic reasoning: statistics base, matrix, and application.  

PubMed

Graphical models for probabilistic reasoning are now in widespread use. Many approaches have been developed such as Bayesian network. A newly developed approach named as dynamic uncertain causality graph (DUCG) is initially presented in a previous paper, in which only the inference algorithm in terms of individual events and probabilities is addressed. In this paper, we first explain the statistic basis of DUCG. Then, we extend the algorithm to the form of matrices of events and probabilities. It is revealed that the representation of DUCG can be incomplete and the exact probabilistic inference may still be made. A real application of DUCG for fault diagnoses of a generator system of a nuclear power plant is demonstrated, which involves variables. Most inferences take with a laptop computer. The causal logic between inference result and observations is graphically displayed to users so that they know not only the result, but also why the result obtained. PMID:24807944

Qin Zhang; Chunling Dong; Yan Cui; Zhihui Yang

2014-04-01

374

Self-affine polytopes. Applications to functional equations and matrix theory  

SciTech Connect

A special kind of functional equation with compression of the argument--the affine self-similarity equation--is studied. The earlier known one-dimensional self-similarity equations are generalized to the multidimensional case of functions of several variables. A criterion for the existence and uniqueness of an L{sub p}-solution is established. Description of such equations involves classification of finite-dimensional convex self-affine compact sets. In this work properties of such objects are thoroughly analysed; in particular, a counterexample to the well-known conjecture about the structure of such bodies, which was put forward in 1991, is given. Applications of the results obtained include some facts about the convergence of products of stochastic matrices; also, criteria for the convergence of some subdivision algorithms are suggested. Bibliography: 39 titles.

Voynov, Andrey S [M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Moscow (Russian Federation)

2011-10-31

375

Influence of the operating conditions and of the optical transition on non-spectral matrix effects in inductively coupled plasma-atomic emission spectrometry  

NASA Astrophysics Data System (ADS)

In order to study in ICP-AES, the influence of the plasma operating conditions, power and carrier gas flow rate, and of the optical transition on non-spectral matrix interferences, line-rich elements such as Mn, Cr and Cu have been selected. Selection of a large pool of lines was possible because of the use of multichannel solid-state detection. An axially viewed plasma was used. Matrices were K, Na, Li, Ca and Mg. Matrix effect was evaluated by comparing the signals for test elements in water. Use of robust conditions led to an almost flat response, while non-robust conditions led to a significant scattering of the signal changes. In the case of Mn, the z 7P Mn multiplet was exemplified as it contains not only the most Mn sensitive line, the Mn II 257.610 nm resonance line, but also the 259.372 and 260.568 nm resonance lines, and the non-resonant Mn II 343.897 nm line. Even under robust conditions, the non-resonant line exhibited a different behavior. The difference with the other resonance lines was reduced by using an axially viewed ICP with a large injector id, or suppressed by using a radially viewed ICP. In the case of Cr, the z 6D Cr II multiplet was selected as it contains three resonant lines linked to the a 6S fundamental, and other non-resonant lines. The behavior was identical under robust conditions, while an abnormal behavior was observed for the Cr II 334.78 nm line under non-robust conditions, depending on the extent of these non-robust conditions. Cu was an interesting element as ionic lines lie in the energy sum range 15.96-16.26 eV, i.e. slightly above the Ar ionization energy. It was shown that, under robust conditions, the line behavior was not similar although the energy range was small. Moreover, this behavior was depending on the ICP system used for the experiment. It was concluded that not only the magnitude of matrix effects depends on the operating conditions but also may depend on the optical transition, illustrating the complexity of these effects.

Iglésias, M.; Vaculovic, T.; Studynkova, J.; Poussel, E.; Mermet, J. M.

2004-12-01

376

The Matrix Market  

NSDL National Science Digital Library

The Matrix Market website, provided by the National Institute of Standards and Technology, is "a visual repository of test data for use in comparative studies of algorithms for numerical linear algebra." The repository includes about 500 sparse matrices from a variety of applications, along with matrix generation tools and services. Visitors can scan the top ten or browse the repository by collection, matrix name, or generator name. Search categories include: by matrix properties, by application area, by contributor, and in bibliography. Tools for browsing through the collection are also included. The Welcome page provides additional information on the project, as well as a few reports and technical presentations.

377

Analytic system matrix resolution modeling in PET: an application to Rb-82 cardiac imaging  

PubMed Central

This work explores application of a novel resolution modeling technique based on analytic physical models which individually models the various resolution degrading effects in PET (positron range, photon non-collinearity, inter-crystal scattering and inter-crystal penetration) followed by their combination and incorporation within the image reconstruction task. In addition to phantom studies, the proposed technique was particularly applied to and studied in the task of clinical Rb-82 myocardial perfusion imaging, which presently suffers from poor statistics and resolution properties in the reconstructed images. Overall, the approach is able to produce considerable enhancements in image quality. The reconstructed FWHM for a Discovery RX PET/CT scanner was seen to improve from 5.1 mm to 7.7 mm across the field-of-view (FoV) to ~3.5 mm nearly uniformly across the FoV. Furthermore, extended-source phantom studies indicated clearly improved images in terms of contrast versus noise performance. Using Monte Carlo simulations of clinical Rb-82 imaging, the resolution modeling technique was seen to significantly outperform standard reconstructions qualitatively, and also quantitatively in terms of contrast versus noise (contrast between the myocardium and other organs, as well as between myocardial defects and the left ventricle).

Rahmim, A; Tang, J; Lodge, M A; Lashkari, S; Ay, M R; Lautamaki, R; Tsui, B M W; Bengel, F M

2011-01-01

378

Durability of polymer matrix composites for automotive structural applications: A state-of-the-art review  

SciTech Connect

A key unanswered question that must be addressed before polymeric composites will be widely used in automotive structural components is their known durability. Major durability issues are the effects that cyclic loadings, creep, automotive fluid environments, and low-energy impacts have on dimensional stability, strength, and stiffness throughout the required life of a composite component. This report reviews the current state of understanding in each of these areas. It also discusses the limited information that exists on one of the prime candidate materials for automotive structural applications--an isocyanurate reinforced with a continuous strand, swirl mat. Because of the key role that nondestructive evaluations must play in understanding damage development and progression, a chapter is included on ultrasonic techniques. A final chapter then gives conclusions and recommendations for research needed to resolve the various durability issues. These recommendations will help provide a sound basis for program planning for the Durability of Lightweight Composite Structures Project sponsored by the US Department of Energy in cooperation with the Automotive Composites Consortium of Chrysler, Ford, and General Motors.

Corum, J.M.; Simpson, W.A. Jr.; Sun, C.T.; Talreja, R.; Weitsman, Y.J.

1995-07-01

379

A Rapidly Deployable Operational Mesoscale Modeling System for Emergency-Response Applications  

Microsoft Academic Search

An operational mesoscale model based forecasting system has been developed for use by U.S. Army Test and Evaluation Command meteorologists in their support of test-range operations. This paper reports on the adaptation of this system to permit its rapid deployment in support of a variety of civilian and military emergency-response applications. The innovation that allows for this rapid deployment is

Thomas T. Warner; James F. Bowers; Scott P. Swerdlin; Brian A. Beitler

2004-01-01

380

s-ordering operator expansions of quantum-mechanical fundamental representations and their applications  

NASA Astrophysics Data System (ADS)

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

Fan, HongYi; Xu, YeJun; Yuan, HongChun

2011-12-01

381

JPEG standard uniform quantization error modeling with applications to sequential and progressive operation modes  

NASA Astrophysics Data System (ADS)

In this paper we propose a method for computing JPEG quantization matrices for a given mean-square error (MSE) or peak signal-to-noise ratio (PSNR). Then, we employ our method to compute JPEG standard progressive operation mode definition scripts using a quantization approach. Therefore, it is no longer necessary to use a trial and error procedure to obtain a desired PSNR and/or definition script, reducing cost. First, we establish a relationship between a Laplacian source and its uniform quantization error. We apply this model to the coefficients obtained in the discrete cosine transform stage of the JPEG standard. Then, an image may be compressed using the JPEG standard under a global MSE (or PSNR) constraint and a set of local constraints determined by the JPEG standard and visual criteria. Second, we study the JPEG standard progressive operation mode from a quantization-based approach. A relationship between the measured image quality at a given stage of the coding process and a quantization matrix is found. Thus, the definition script construction problem can be reduced to a quantization problem. Simulations show that our method generates better quantization matrices than the classical method based on scaling the JPEG default quantization matrix. The estimation of PSNR has usually an error smaller than 1 dB. This figure decreases for high PSNR values. Definition scripts may be generated avoiding an excessive number of stages and removing small stages that do not contribute during the decoding process with a noticeable image quality improvement.

Minguillon, Julia; Pujol, Jaume

2001-04-01

382

The Hellmann-Feynman theorem for approximate wave functions and its application to nonadiabatic coupling matrix elements with the aid of a coupled Hartree-Fock method  

Microsoft Academic Search

Nonadiabatic coupling matrix elements are calculated by means of the Hellmann-Feynman theorem. Thereby the basis set dependence is investigated thoroughly for GTO basis sets. For every occupied AO, at least two polarization functions have to be included, of which the K shell p function have to be taken into special consideration. In this report we will show applications for the

Peter Habitz; Christian Votava

1980-01-01

383

Processing, Compatibility and Oxidation of Diboride - Oxide Matrix Composites for Ultrahigh-Temperature Applications.  

NASA Astrophysics Data System (ADS)

Promising results for the development of a ceramic/ceramic composite to be used for structural applications in the ultra high temperature range (1650-1850^ circC) have been obtained for alumina reinforced with titanium or zirconium diboribe coated with molybdenum disilicide. Prior to this achievement, several theoretical and experimental studies of particulate composites with (TiB_2 or ZrB_2) imbedded in (ZrO_2, Y_2 O_3 or Al_2 O_3) were conducted. Calculations of the compatibility and stability of oxide matrices with the diborides in vacuum showed positive energies of formation, indicating suitability of reinforcement of alumina under vacuum conditions. Also, since the sublimation of vapor species at ultra high temperatures is very critical to the stability of substances still existing in their condensed states, a detailed thermodynamic analysis of the metal -oxygen systems, was carried out using elemental data of the TiB_2, ZrB_2 , ZrO_2, Y_2 O_3, Al_2 O_3, MoSi_2 and their combinations (TiB_2 or ZrB_2)/(ZrO_2 , Y_2O_3 or Al_2O_3) for comparison, at 1650, 1850 and 2050^ circC. A comparison of the combination TiB _2 and ZrB_2 in MoSi_2/(Al_2O _3 or ZrO_2) at 1650^circC was also made. A stability analysis using equilibrium oxygen partial pressures for the TiB_2 and ZrB_2 decomposition at 1650, 1850 and 2050^ circC was carried out. A detailed characterization of the powders used for the oxide matrices, the diborides and the molybdenum disilicide are presented. The effects of the powder characteristics and the vacuum hot pressing parameters on the densification of the composites are discussed. Stability and chemical compatibility of the particulate and ternary composites in their as hot pressed states and following their vacuum and air oxidation treatments were characterized. Interdiffusion of elemental species across diboride/disilicide and oxide/disilicide interfaces was studies by EDS dot mapping. It is proposed that the growth of the Mo _5Si_3 is interface reaction controlled. It is proposed that diffusion of atmospheric gaseous oxygen through the porous texture left by the initial reaction of the oxide and diboride to form volatile B_2O_3 accounts for the continued erosion of the structure. (Abstract shortened with permission of author.).

Abada, Ahmed

1990-01-01

384

[Operating rules of cotton-pave moxibustion and its samples for clinical application in dermatopathy].  

PubMed

In clinical researches, the authors find that cotton-pave moxibustion has obvious effect for treatment of common dermatopathy, such as herpes zoster. This therapy has some advantages such as easy operation, obvious clinical effect, slight and short burning pain and easy to be accepted by patients. The purpose of this paper is to make the operation of cotton-pave moxibustion standardized, spread and popularize the application of this therapy in dermatopathy through detailed description to the operation method and points for attention of cotton-pave moxibustion and its typical cases. PMID:20496738

Li, Xue-wei; Zuo, Jia; Huang, Wei-ling; Yang, Yun-kuan

2010-03-01

385

Space Environments and Effects Concept: Transitioning Research to Operations and Applications  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration (NASA) is embarking on a course to expand human presence beyond Low Earth Orbit (LEO) while expanding its mission to explore the solar system. Destinations such as Near Earth Asteroids (NEA), Mars and its moons, and the outer planets are but a few of the mission targets. NASA has established numerous offices specializing in specific space environments disciplines that will serve to enable these missions. To complement these existing discipline offices, a concept focusing on the development of space environment and effects application is presented. This includes space climate, space weather, and natural and induced space environments. This space environment and effects application is composed of 4 topic areas; characterization and modeling, engineering effects, prediction and operation, and mitigation and avoidance. These topic areas are briefly described below. Characterization and modeling of space environments will primarily focus on utilization during Program mission concept, planning, and design phases. Engineering effects includes materials testing and flight experiments producing data to be used in mission planning and design phases. Prediction and operation pulls data from existing sources into decision-making tools and empirical data sets to be used during the operational phase of a mission. Mitigation and avoidance will develop techniques and strategies used in the design and operations phases of the mission. The goal of this space environment and effects application is to develop decision-making tools and engineering products to support the mission phases of mission concept through operations by focusing on transitioning research to operations. Products generated by this space environments and effects application are suitable for use in anomaly investigations. This paper will outline the four topic areas, describe the need, and discuss an organizational structure for this space environments and effects application.

Edwards, David L.; Spann, James; Burns, Howard D.; Schumacher, Dan

2012-01-01

386

Nanocrystal doped matrixes  

DOEpatents

Matrixes doped with semiconductor nanocrystals are provided. In certain embodiments, the semiconductor nanocrystals have a size and composition such that they absorb or emit light at particular wavelengths. The nanocrystals can comprise ligands that allow for mixing with various matrix materials, including polymers, such that a minimal portion of light is scattered by the matrixes. The matrixes of the present invention can also be utilized in refractive index matching applications. In other embodiments, semiconductor nanocrystals are embedded within matrixes to form a nanocrystal density gradient, thereby creating an effective refractive index gradient. The matrixes of the present invention can also be used as filters and antireflective coatings on optical devices and as down-converting layers. Processes for producing matrixes comprising semiconductor nanocrystals are also provided. Nanostructures having high quantum efficiency, small size, and/or a narrow size distribution are also described, as are methods of producing indium phosphide nanostructures and core-shell nanostructures with Group II-VI shells.

Parce, J. Wallace (Palo Alto, CA); Bernatis, Paul (Sunnyvale, CA); Dubrow, Robert (San Carlos, CA); Freeman, William P. (San Mateo, CA); Gamoras, Joel (Vallejo, CA); Kan, Shihai (San Jose, CA); Meisel, Andreas (Redwood City, CA); Qian, Baixin (Sunnyvale, CA); Whiteford, Jeffery A. (Belmont, CA); Ziebarth, Jonathan (Palo Alto, CA)

2010-01-12

387

Computation of the cycle state-variable sensitivity matrix of PWM DC\\/DC converters and its applications  

Microsoft Academic Search

This paper presents a generalized technique for computation of cycle state-variable sensitivity matrix of pulse-width-modulated (PWM) dc\\/dc converters. It determines the sensitivity of the state variable variation, with the inclusion of the effects of changing the topology duration on the sensitivity matrix. A basic sensitivity graph for each circuit topology is derived. By cascading corresponding graphs, a sensitivity matrix of

Billy K. H. Wong; Henry S. H. Chung; Stephen T. S. Lee

2000-01-01

388

Comment on "Photoionization of endohedral atoms using R-matrix methods: Application to Xe@C60"  

NASA Astrophysics Data System (ADS)

We demonstrate that what is called a total photoionization cross section in the work by T. W. Gorczyca, M. F. Hasoglu, and S. T. Manson [Phys. Rev. A 86, 033204 (2012), 10.1103/PhysRevA.86.033204] is in fact a partial photoionization cross section. These quantities differ impressively even in isolated atoms. This demonstrates the prominent role of inelastic collisions of a photoelectron from an intermediate or inner shell not mentioned in their paper. We discuss briefly the correspondence between the experimental data, theoretical predictions, and R-matrix results from Phys. Rev. A 86, 033204 (2012), 10.1103/PhysRevA.86.033204. We call attention to the danger in using parameters of C60 potential selected by fitting the same experimental data that one wants to describe. We show that our criticism is applicable to the theoretical part of the most recent publication on photoionization of Xe @C60+ [10 R. A. Phaneuf et al., Phys. Rev. A 88, 053402 (2013), 10.1103/PhysRevA.88.053402].

Amusia, M. Ya.; Chernysheva, L. V.

2014-05-01

389

[Study on application of bioassay method in drug-release evaluation in vitro of Salvia miltiorrhiza hydrophilic gel matrix tablets].  

PubMed

To investigate the feasible application of the bioassay method in the evaluation of traditional Chinese medicine sustained-release preparations, develop a rapid drug-release evaluation method in vitro for multi-component preparations, and replace the biological activity determination method characterizing the overall behavior with the existing drug-release evaluation method for single component, in order to give better instruction for sustained-release preparations. HPLC was adopted to determine dissolution media, drug releasing rates, and accumulative releasing of active ingredients (salvianolic acid B, protocatechuic aldehyde and rosmarinic acid) of Salvia Miltiorrhiza hydrophilic gel matrix tablets. The ultraviolet spectroscopy was adopted to determine the antioxidant activity of release media, and evaluate the correlation between the drug-time curve of various drug components and the drug-time curve of the total antioxidant activity. The correlation coefficient between the drug-release curve of various components and the drug-time curve of the total antioxidant activity was higher than the critical value r 0.898 (P < 0.001). This indicated that the drug-release curve of the three phenolic acids and the drug-time curve of the total antioxidant activity had a good correlation in different conditions, such as dissolution media, release rates and component ratios. The bioassay method for determination was feasible, simple and convenient for preparation quality evaluation and prescription design in the place of in vitro dissolution. PMID:24558869

Li, Dong-Ying; Liu, Xiao-Qian; Feng, Wei-Hong; Wang, Zhi-Min; Yi, Hong; Meng, Qing-Ju

2013-11-01

390

Fractional calculus operators and their applications involving power functions and summation of series  

Microsoft Academic Search

Many earlier works on the subject of fractional calculus contain interesting accounts of the theory and applications of fractional calculus operators in a number of areas of mathematical analysis (such as ordinary and partial differential equations, integral equations, summation of series, etc.). The main object of this paper is to examine rather systematically (and extensively) some of the most recent

H. M. Srivastava

1997-01-01

391

An investigation of potential applications of OP-SAPS: Operational Sampled Analog Processors  

NASA Technical Reports Server (NTRS)

The application of OP-SAP's (operational sampled analog processors) in pattern recognition system is summarized. Areas investigated include: (1) human face recognition; (2) a high-speed programmable transversal filter system; (3) discrete word (speech) recognition; and (4) a resolution enhancement system.

Parrish, E. A.; Mcvey, E. S.

1977-01-01

392

Fifth Annual Workshop on Space Operations Applications and Research (SOAR 1991), volume 2  

NASA Technical Reports Server (NTRS)

Papers given at the Space Operations and Applications Symposium, host by the NASA Johnson Space Center on July 9-11, 1991 are given. The technical areas covered included intelligent systems, automation and robotics, human factors and life sciences, and environmental interactions.

Krishen, Kumar (editor)

1992-01-01

393

A study on applications of energy storage for the wind power operation in power systems  

Microsoft Academic Search

Energy storage system (ESS) has been studied as a high-tech solution for managing power flows from wind turbine generator (WTG), and making them be competitive energy sources without putting power systems at risk. This paper illustrates possible applications of the energy storage for the wind power operating in power systems focusing on its short-duration prospective. Employing a sample power system,

Kyung Soo Kook; Keith J. McKenzie; Yilu Liu; Stan Atcitty

2006-01-01

394

76 FR 12140 - Clinton Power Station Notice of Withdrawal of Application for Amendment to Facility Operating...  

Federal Register 2010, 2011, 2012, 2013

...Docket No. 50-461; NRC-2011-0050] Clinton Power Station Notice of Withdrawal of Application...Operating License No. NPF-62 for the Clinton Power Station, Unit 1, located in DeWitt County, Illinois. The proposed amendment would have...

2011-03-04

395

A Neo-Piagetian Theory of Constructive Operators: Applications to Perceptual-Motor Development and Learning.  

ERIC Educational Resources Information Center

The author presents an overview of Pascual-Leone's Theory of Constructive Operators, a process-structural theory based upon Piagetian constructs which has evolved to both explain and predict the temporal unfolding of behavior. An application is made of the theory to the demands of a discrete motor task and prediction of (a) the minimal age…

Todor, John I.

396

MODAL TESTING AND ANALYSIS OF STRUCTURES UNDER OPERATIONAL CONDITIONS: INDUSTRIAL APPLICATIONS  

Microsoft Academic Search

Experimental identification of structural dynamics models is usually based on the modal analysis approach. In the classical modal parameter estimation approach, the baseline data which are processed are frequency response functions measured under laboratory conditions. However, in many applications, the real operating conditions may differ significantly from those applied during the modal test. Hence, the need arises to identify a

L. Hermans; H. VAN DER AUWERAER

1999-01-01

397

Bayesian Copulae Distributions, with Application to Operational Risk Management—Some Comments  

Microsoft Academic Search

This paper points out mistakes in some results given in the paper “Bayesian Copulae Distributions, with Application to Operational Risk Management” by Luciana Dalla Valle, published in 2009 in volume 11, number 1 of “Methodology and Computing in Applied Probability”.\\u000a In particular, we explain why the inverse Wishart distribution is not a conjugate prior to the Gaussian copula.

Philipp Arbenz

398

Industrial application of multivariate SPC to continuous caster start-up operations for breakout prevention  

Microsoft Academic Search

Breakouts are of major concern in the continuous steel-casting process, because they can lead to severe damage to equipment, significant process downtime, and potential safety consequences. Dofasco's plant experiences show that approximately 25% of breakouts occur during the caster start-up operation. This paper describes an advanced industrial application of the Multiway Principal Component Analysis (MPCA) method to monitor continuous caster

Yale Zhang; Michael S. Dudzic

2006-01-01

399

Regulating manure application discharges from concentrated animal feeding operations in the United States  

Microsoft Academic Search

In the United States, reducing pollution from agriculture has received attention due to data suggesting that this is the leading source of impairment of many waterbodies. The federal government revised its regulations governing concentrated animal feeding operations (CAFOs) to enhance governmental oversight over sources of pollution. For the application of manure resulting in pollutant discharges, CAFOs need to implement nutrient

Terence J. Centner; Theodore A. Feitshans

2006-01-01

400

Production scheduling and operational control: New algorithms with applications to the mining industry  

Microsoft Academic Search

In this thesis, several aspects of production scheduling and operational control problems have been investigated. The scope of the study has included (a) analysis of current issues, (b) development of related theory, mathematical modeling, and solution algorithms, (c) implementation, validation, and application demonstration of the models developed in this research. A new algorithm integrating the dynamic programming and branch-and-bound techniques,

1992-01-01

401

Receiver operating characteristic (ROC) analysis: Basic principles and applications in radiology  

Microsoft Academic Search

Receiver operating characteristic (ROC) analysis is a widely accepted method for analyzing and comparing the diagnostic accuracy of radiological tests. In this paper we will explain the basic principles underlying ROC analysis and provide practical information on the use and interpretation of ROC curves. The major applications of ROC analysis will be discussed and their limitations will be addressed.

Arian R van Erkel; Peter M. Th Pattynama

1998-01-01

402

3D exploitation system for operational applications of Earth observation data  

NASA Astrophysics Data System (ADS)

The operational applicability of Earth Observation data to facilitate decision making is demonstrated with examples taken from the work of the Western European Union Satellite Center in Madrid. Analysis and reporting techniques based on 3D representations of the surface of the Earth and Virtual Reality are described.

Bonavenia, Roberto; Colaiacomo, Lucio; Dooley, Colin; Menu, Eric; Palumbo, Gianluca; Prisco, Giulio; Valero, Juan L.; Villemaud, Olivier

1999-07-01

403

An Operational Safety and Certification Assessment of a TASAR EFB Application  

NASA Technical Reports Server (NTRS)

This paper presents an overview of a Traffic Aware Strategic Aircrew Requests (TASAR) Electronic Flight Bag application intended to inform the pilot of trajectory improvement opportunities while en route that result in operational benefits. The results of safety analyses and a detailed review of Federal Aviation Administration (FAA) regulatory documents that establish certification and operational approval requirements are presented for TASAR. The safety analyses indicate that TASAR has a likely Failure Effects Classification of “No Effect,” and at most, is no worse than “Minor Effect.” Based on this safety assessment and the detailed review of FAA regulatory documents that determine certification and operational approval requirements, this study concludes that TASAR can be implemented in the flight deck as a Type B software application hosted on a Class 2 Portable Electronic Device (PED) Electronic Flight Bag (EFB). This implementation approach would provide a relatively low-cost path to certification and operational approval for both retrofit and forward fit implementation, while at the same time facilitating the business case for early ADS-B IN equipage. A preliminary review by FAA certification and operational approvers of the analyses presented here confirmed that the conclusions are appropriate and that TASAR will be considered a Type B application.

Koczo, Stefan; Wing, David

2013-01-01

404

Rationale, Scenarios, and Profiles for the Application of the Internet Protocol Suite (IPS) in Space Operations  

NASA Technical Reports Server (NTRS)

This greenbook captures some of the current, planned and possible future uses of the Internet Protocol (IP) as part of Space Operations. It attempts to describe how the Internet Protocol is used in specific scenarios. Of primary focus is low-earth-orbit space operations, which is referred to here as the design reference mission (DRM). This is because most of the program experience drawn upon derives from this type of mission. Application profiles are provided. This includes parameter settings programs have proposed for sending IP datagrams over CCSDS links, the minimal subsets and features of the IP protocol suite and applications expected for interoperability between projects, and the configuration, operations and maintenance of these IP functions. Of special interest is capturing the lessons learned from the Constellation Program in this area, since that program included a fairly ambitious use of the Internet Protocol.

Benbenek, Daniel B.; Walsh, William

2010-01-01

405

OPERATING TEMPERATURE WINDOW FOR SIC CERAMICS AND COMPOSITESFOR FUSION ENERGY APPLICATIONS  

SciTech Connect

Limitations in operating conditions, primarily the steady-state operating temperature, of silicon carbide-based ceramics and composites for applications to structural and functional components in fusion blanket systems were critically examined based on the latest experimental results. Irradiation-induced high temperature swelling and irradiation creep were identified to be the likely factors limiting the upper temperature bound for structural applications, whereas irradiation-induced thermal conductivity degradation was identified to be the primary factor to limit the lower temperature bound when substantial heat flux is anticipated. For the application to flow channel inserts in liquid metal blankets, insulating properties will likely limit the upper temperature bound, whereas the lower temperature bound may be limited by swelling-induced secondary stress. Additionally, key scientific issues which need to be addressed for the better definition of design limitations were identified.

Katoh, Yutai [ORNL; Snead, Lance Lewis [ORNL

2009-01-01

406

Improvement of the maxillary bone growth suppression in the cleft palate operation with cultured dermal substitute: animal experiment and patient reports in preliminary clinical application.  

PubMed

Cleft palate patients often show impaired maxillary bone growth after cleft-palate-correction surgery. We attempted to investigate and elucidate the effects of using allogeneic, cultured dermal substitute (CDS) to cover an exposed, palatal bone surface in animal experiments. Fibroblasts from the abdominal skin of Wistar rats were cultured. Subsequently, the fibroblasts were seeded onto a matrix that composed of hyaluronic acid and atelo-collagen. Forty Wistar rats (3-week-old males) were assigned to one of four groups: control, open-treatment, matrix and CDS groups. The control group (n=5) received no surgical operations. In the open-treatment group (n=11), the mucosa and periosteum of the left-half of the palate were removed surgically and the bone was exposed. In the matrix group (n=11), the area of exposed bone was covered with only the matrix, excluding any cells. In the CDS group (n=10), the area of exposed bone was covered with CDS. At 9 weeks postoperatively, biopsies of the wounds were obtained. Skull preparations were made and the palatal widths were determined. The palatal widths in the CDS group were significantly wider compared to the matrix and open-treatment groups (P<0.05). However, there were no significant differences when the CDS group was compared to the control group. Haematoxylin, eosin and CD31 immunostaining confirmed a larger number of capillaries in the CDS group. This animal experiment suggested that this procedure might provide an optimum wound-healing condition, thus, reducing the maxillary bone-growth suppression. Therefore, a preliminary clinical application in three patients was performed using the autologous CDS after the pushback method. PMID:19251505

Kurokawa, N; Ueda, K; Kuroyanagi, Y

2010-03-01

407

46 CFR 70.05-18 - Applicability to vessels operating under an exemption afforded in the Passenger Vessel Safety Act...  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Applicability to vessels operating under an exemption afforded in the Passenger Vessel Safety Act of 1993 (PVSA). 70.05-18...HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS GENERAL PROVISIONS Application...

2013-10-01

408

Optical Matrix.Matrix Multiplier  

NASA Technical Reports Server (NTRS)

Proposed apparatus for optical multiplication of two matrices based on Stanford optical vector.matrix multiplier. Does not require redundant representation of one of matrices. Because apparatus performs multiplication in fully parallel manner, incorporated as subsystem into large optical-processing system. Optical matrix.matrix multiplier processes inputs in fully parallel fashion, without redundant matrix images or ancillary intermediate electronic processing.

Gheen, Gregory

1989-01-01

409

Hybrid matrix amplifier  

DOEpatents

The present invention comprises a novel matrix amplifier. The matrix amplifier includes an active superconducting power divider (ASPD) having N output ports; N distributed amplifiers each operatively connected to one of the N output ports of the ASPD; and a power combiner having N input ports each operatively connected to one of the N distributed amplifiers. The distributed amplifier can included M stages of amplification by cascading superconducting active devices. The power combiner can include N active elements. The resulting (N.times.M) matrix amplifier can produce signals of high output power, large bandwidth, and low noise.

Martens, Jon S. (Sunnyvale, CA); Hietala, Vincent M. (Placitas, NM); Plut, Thomas A. (Albuquerque, NM)

1995-01-01

410

Hybrid matrix amplifier  

DOEpatents

The present invention comprises a novel matrix amplifier. The matrix amplifier includes an active superconducting power divider (ASPD) having N output ports; N distributed amplifiers each operatively connected to one of the N output ports of the ASPD; and a power combiner having N input ports each operatively connected to one of the N distributed amplifiers. The distributed amplifier can included M stages of amplification by cascading superconducting active devices. The power combiner can include N active elements. The resulting (N[times]M) matrix amplifier can produce signals of high output power, large bandwidth, and low noise. 6 figures.

Martens, J.S.; Hietala, V.M.; Plut, T.A.

1995-01-03

411

Applicability of the Decision Matrix of North Eastern Atlantic, Mediterranean and connected seas Tsunami Warning System to the Italian tsunamis  

NASA Astrophysics Data System (ADS)

After the 2004 Indian Ocean tsunami catastrophe, UNESCO through the IOC (Intergovernmental Oceanographic Commission) sponsored the establishment of Intergovernmental Coordination Groups (ICG) with the aim to devise and implement Tsunami Warning Systems (TWSs) in all the oceans exposed to tsunamis, in addition to the one already in operation in the Pacific (PTWS). In this context, since 2005, efforts have begun for the establishment of TWSs in the Indian Ocean (IOTWS), in the Caribbean area (CARIBE EWS) and in the North Eastern Atlantic, the Mediterranean and Connected Seas (NEAMTWS). In this paper, we focus on a specific tool that was first introduced in the PTWS routine operations, i.e., the Decision Matrix (DM). This is an easy-to-use table establishing a link between the main parameters of an earthquake and the possible ensuing tsunami in order to make quick decision on the type of alert bulletins that a Tsunami Warning Center launches to its recipients. In the process of implementation of a regional TWS for the NEAM area, two distinct DMs were recently proposed by the ICG/NEAMTWS, one for the Atlantic and the other for the entire Mediterranean area. This work applies the Mediterranean NEAMTWS DM to the earthquakes recorded in Italy and compares the action predicted by the DM vs. the action that should be appropriate in view of the observed tsunami characteristics with the aim to establish how good the performance of the Italian TWS will be when it uses the DM for future events. To this purpose, we make use of the parametric catalogue of the Italian earthquakes (CPTI04) compiled in 2004 and the most recent compilation of the Italian tsunami, based on the Italian Tsunami Catalogue of 2004 and the subsequent revisions. In order to better compare the TWS actions, we have identified four different kinds of action coding them from 0 to 3 according to the tsunami severity and have further considered three different distance ranges where these actions apply, that is local, regional and basin-wide, that refer to the distance of the message recipients from the tsunami source. The result of our analysis is that the actions prescribed by the DM are adequate only in 45%-55% of the cases, overestimations are about 37% and underestimations are the rest. As a whole, the predictive ability of the DM is not satisfactory, which implies that recipients have the difficult task in managing bulletins carrying a great deal of uncertainty and on the other hand also suggests that strategies to improve the DM or to go beyond the DM need to be found.

Tinti, S.; Graziani, L.; Brizuela, B.; Maramai, A.; Gallazzi, S.

2012-03-01

412

The renormalization of several composite operator insertions, Wilson expansions of composite operators, and the applications to short-distance behaviour  

Microsoft Academic Search

We examine the renormalization of composite operator insertions within a normal product framework, and prove various identities between composite operator insertions. In particular a proof of the Wilson expansion of composite operators in the presence of other composite operators is given. The analysis necessitates a re-examination of several physical processes, and it is shown in particular why the results for

P. S. Collecott

1978-01-01

413

Controlled release of insulin from self-assembling nanofiber hydrogel, PuraMatrix™: application for the subcutaneous injection in rats.  

PubMed

The concept of this research is, using the acetyl-(Arg-Ala-Asp-Ala)?-CONH? peptide hydrosol (PuraMatrix™, PM), to develop an new injectable formula of controlled insulin delivery for subcutaneous injection. PM has sol-gel phase transition behavior, and was developed as a scaffold in the field of tissue engineering. The aqueous media of the PM including insulin changed from a sol to a gel phase with increasing ion strength of phosphate ion and pH in working environments in vitro and in vivo. In this study, we examined the in vitro insulin dissolution behavior and the in vivo pharmacokinetics and pharmacodynamics after subcutaneous administration of PM-insulin sol (PM-Isol). In the in vitro release study, after PM-Isol was converted to a gel phase (PM-Igel), PM concentration-dependent and controlled release of insulin were observed at the final concentrations of PM between 0.1% and 2.0% (w/v). The PM-Isol is changed to gel form in vivo, and exhibited a sustained-release pharmacokinetics of insulin, where PM concentration-dependent prolongation of efficacy was found. The plasma glucose level markedly decreased, and the lowest plasma glucose level was maintained up to 24h when 2.0% (w/v) PM-Isol was administered subcutaneously to rats. The PM-Isol, we developed here, is applicable for the wild-type of insulin, and increased the bioavailability and hypoglycemic efficacy of insulin after subcutaneous injection. Hence, the PM is a useful inactive ingredient to produce various types of control-released system of insulin by making just a few changes in PM content of the formulation. PMID:22064453

Nishimura, Asako; Hayakawa, Taro; Yamamoto, Yu; Hamori, Mami; Tabata, Keiko; Seto, Keiko; Shibata, Nobuhito

2012-01-23

414

Using reactor operating experience to improve the design of a new Broad Application Test Reactor  

SciTech Connect

Increasing regulatory demands and effects of plant aging are limiting the operation of existing test reactors. Additionally, these reactors have limited capacities and capabilities for supporting future testing missions. A multidisciplinary team of experts developed sets of preliminary safety requirements, facility user needs, and reactor design concepts for a new Broad Application Test Reactor (BATR). Anticipated missions for the new reactor include fuels and materials irradiation testing, isotope production, space testing, medical research, fusion testing, intense positron research, and transmutation doping. The early BATR design decisions have benefited from operating experiences with existing reactors. This paper discusses these experiences and highlights their significance for the design of a new BATR.

Fletcher, C.D.; Ryskamp, J.M.; Drexler, R.L.; Leyse, C.F.

1993-07-01

415

Sixth Annual Workshop on Space Operations Applications and Research (SOAR 1992), volume 2  

NASA Technical Reports Server (NTRS)

This document contains papers presented at the Space Operations, Applications, and Research Symposium (SOAR) hosted by the U.S. Air Force (USAF) on 4-6 Aug. 1992. The symposium was cosponsored by the Air Force Material Command and by NASA/JSC. Key technical areas covered during the symposium were robotics and telepresence, automation and intelligent systems, human factors, life sciences, and space maintenance and servicing. The SOAR differed from most other conferences in that it was concerned with Government-sponsored research and development relevant to aerospace operations. Symposium proceedings include papers covering various disciplines presented by experts from NASA, the USAF, universities, and industry.

Krishen, Kumar (editor)

1993-01-01

416

The Application of Performance Assessment to Make Regulatory and Operational Changes in an Operating Nuclear Waste Repository  

SciTech Connect

This paper describes how performance assessment (PA) is used to support changes to the regulatory basis of the Waste Isolation Pilot Plant (WIPP). The WIPP, located near Carlsbad, New Mexico is operated by the U.S. Department of Energy (DOE) as the nation's only deep geologic repository for the disposal of transuranic nuclear waste. In 1998, the Environmental Protection Agency (EPA) certified that the WIPP met the performance requirements of 40 CFR Part 191, Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes. A PA analysis of long term (10,000 year) repository performance successfully demonstrated that the probability and consequences of potential long-term releases of radionuclides to the accessible environment would be well below the established limits. These results were key in obtaining WIPP's initial certification, allowing the first shipment and disposal of nuclear waste in March of 1999. As disposal operations have taken place over the last eight years, changes have been identified in the regulatory and operational realms of the facility that would enhance waste disposal efficiency. Such changes, however, cannot be made without prior consent of the EPA. Therefore, changes planned by the DOE must be thoroughly described and supported by varying degrees of the same type of analyses that were conducted to demonstrate the WIPP's containment capabilities as presented in the initial compliance application submitted to EPA in 1996. Such analyses are used to identify the impacts or benefits of implementing the planned change. The DOE has successfully used performance assessment analyses for the approval of changes such as: 1) the disposal of super-compacted waste forms, and; 2) the adoption of new parameters and modeling assumptions In some cases the planned changes are simpler in nature than those listed above, and therefore only require targeted or simplified PA analyses to demonstrate the effect on performance. Targeted analyses have been used to successfully gain approval of the following: 1) a reduction in the amount of magnesium oxide (MgO) chemical buffer backfill that must be emplaced in the repository 2) a change in the repository mining/disposal horizon In addition to these approved changes, the DOE has used PA analyses to support the following planned change requests that await EPA's approval: 1) panel closure redesign 2) further reduction in the MgO-to-waste ratio Finally, this paper will discuss some of the changes that the DOE is currently preparing and plans to submit to the EPA for approval in the near future. This paper will describe how a set of analytical tools initially used to open the WIPP continues to have a role in making the repository more efficient and adaptable as variations in waste streams, operational demands, and other dynamic forces change the operating environment over time. (authors)

Patterson, R. [Department of Energy, Carlsbad Field Office, Carlsbad, NM (United States); Kirkes, R. [John Hart and Associates, P.A., Albuquerque, NM (United States)

2008-07-01

417

Solar photovoltaic applications seminar: design, installation and operation of small, stand-alone photovoltaic power systems  

SciTech Connect

This seminar material was developed primarily to provide solar photovoltaic (PV) applied engineering technology to the Federal community. An introduction to photoconductivity, semiconductors, and solar photovoltaic cells is included along with a demonstration of specific applications and application identification. The seminar details general systems design and incorporates most known information from industry, academia, and Government concerning small solar cell power system design engineering, presented in a practical and applied manner. Solar PV power system applications involve classical direct electrical energy conversion and electric power system analysis and synthesis. Presentations and examples involve a variety of disciplines including structural analysis, electric power and load analysis, reliability, sizing and optimization; and, installation, operation and maintenance. Four specific system designs are demonstrated: water pumping, domestic uses, navigational and aircraft aids, and telecommunications. All of the applications discussed are for small power requirement (under 2 kilowatts), stand-alone systems to be used in remote locations. Also presented are practical lessons gained from currently installed and operating systems, problems at sites and their resolution, a logical progression through each major phase of system acquisition, as well as thorough design reviews for each application.

Not Available

1980-07-01

418

Backscattering Mueller matrix for quasi-horizontally oriented ice plates of cirrus clouds: application to CALIPSO signals.  

PubMed

A general view of the backscattering Mueller matrix for the quasi-horizontally oriented hexagonal ice crystals of cirrus clouds has been obtained in the case of tilted and scanning lidars. It is shown that the main properties of this matrix are caused by contributions from two qualitatively different components referred to the specular and corner-reflection terms. The numerical calculation of the matrix is worked out in the physical optics approximation. These matrices calculated for two wavelengths and two tilt angles (initial and present) of CALIPSO lidar are presented as a data bank. The depolarization and color ratios for these data have been obtained and discussed. PMID:23263056

Borovoi, Anatoli; Konoshonkin, Alexander; Kustova, Natalia; Okamoto, Hajime

2012-12-17

419

Wide temperature operation of 850-nm VCSEL and isolator-free operation of 1300-nm VCSEL for a variety of applications  

Microsoft Academic Search

Furukawa Electric is looking at a variety of applications using VCSEL. New applications such as sensors, automobile, and home electric appliances require new characteristics of stable CW operation, higher modulation, wider temperature range, and higher density array. Automobile Local Area Network called MOST (Media Orientated System Transport) is now popular using 650 nm LED plus Plastic Optical Fiber with a

Kevin Nishikata; Maiko Ariga; Norihiro Iwai; Yoshihiko Ikenaga; Casimirus Setiagung; Takeo Kageyama; Hitoshi Shimizu; Noriyuki Yokouchi; Akihiko Kasukawa; Fumio Koyama

2005-01-01

420

Solar thermal system for lunar ISRU applications: development and field operation at Mauna Kea, HI  

NASA Astrophysics Data System (ADS)

This paper discusses the development, deployment and operation of the optical waveguide (OW) solar thermal power system for In-Situ Resource Utilization (ISRU) applications at the NASA ISRU analog test site on Mauna Kea, HI. In this solar thermal system, solar radiation is collected by the concentrator array which transfers the concentrated solar radiation to the OW transmission line made of low loss optical fibers. The OW transmission line directs the solar radiation to the place of utilization of the solar energy. In this paper applications of solar energy to sintering of native soil for surface stabilization and thermo-chemical processing of native soil for oxygen production are discussed.

Nakamura, Takashi; Smith, Benjamin K.

2011-09-01

421

Application of X-ray K-edge densitometry in D and D operations  

SciTech Connect

K-edge densitometry is a nondestructive assay technique which provides accurate measurement of heavy metal contamination in pipes, containers, and other items encountered in D and D operations. A prototype mobile K-edge instrument has been built and demonstrated in several applications. Results from measurements of uranium in pipes and spent reactor fuel plates, and quantification of mercury and lead in waste drums are presented. In this report the authors briefly describe the theory behind K-edge densitometry. They follow that with a description of the prototype system they have developed, and a presentation of results from demonstrations of this system. They conclude with a discussion of the potential for application of K-edge analysis in D and D operations.

Jensen, T.; Aljundi, T.; Gray, J.N. [Ames Lab., IA (United States)]|[Iowa State Univ., Ames, IA (United States). Center for NDE

1998-12-31

422

Regulating manure application discharges from concentrated animal feeding operations in the United States.  

PubMed

In the United States, reducing pollution from agriculture has received attention due to data suggesting that this is the leading source of impairment of many waterbodies. The federal government revised its regulations governing concentrated animal feeding operations (CAFOs) to enhance governmental oversight over sources of pollution. For the application of manure resulting in pollutant discharges, CAFOs need to implement nutrient management plans. A federal court affirmed the ability of the US federal government to oversee the application of manure from CAFOs that have discharges. Simultaneously, owners and operators of CAFOs who have implemented an appropriate nutrient management plan may forgo securing a permit if their discharges qualify under the agricultural stormwater discharge exemption. PMID:16271814

Centner, Terence J; Feitshans, Theodore A

2006-06-01

423

Rapid pentachlorophenol evaluation in solid matrixes by second derivative UV spectroscopy for application to wood and leather samples  

SciTech Connect

A method for the quail-quantitative evaluation of pentachlorophenol (PCP) in solid matrixes has been developed. The procedure is based on solid-liquid extraction of solid samples (leather or wood), followed by purification on a cyanopropyl column and determination of the preservative by second derivative UV spectroscopy considering the PCP A peak-through value (304-297 nm). The method allows rapid PCP determination in the concentration range 1-40 micrograms/mL; any matrix interference is avoided by the purification step and recoveries of the preservative were 99.12% (RSD% 0.13) for the leather matrix and 98.03 (RSD% 0.17) for the wood matrix.

Secchieri, M.; Benassi, C.A.; Pastore, S.; Semenzato, A.; Bettero, A.; Levorato, M.; Guerrato, A. (Universita di Padova, Dipartimento di Scienze Farmaceutiche (Italy))

1991-07-01

424

Chemical Compatibility and Oxidation Resistance of Potential Matrix and Reinforcement Materials in Ceramic Composites for Ultra-High Temperature Applications.  

National Technical Information Service (NTIS)

The mutual chemical composition and compatibilities of some of the potential matrix and reinforcement phases of ceramic composite materials have been investigated in the temperature range 1600-2200 C. The oxidative stabilities of hot pressed, particulate ...

G. M. Mehrotra

1991-01-01

425

A gelatin matrix-thrombin tissue sealant (FloSeal) application in the management of groin breakdown after inguinal lymphadenectomy for vulvar cancer.  

PubMed

The rate of groin breakdown after radical wide vulvar excision and inguinal lymphadenectomy for vulvar cancer remains significant despite conservative surgical approaches. An 86-year-old Latin American woman underwent wide radical excision and bilateral inguinal lymphadenectomy for vulvar cancer. The postoperative course was complicated by bilateral groin wound separation and high output lymphorrhea. The patient responded to the application of a gelatin matrix-thrombin tissue sealant (FloSeal) to the bases of each groin with resolution in lymphorrhea and formation of granulation tissue. The application of a gelatin matrix-thrombin tissue sealant (FloSeal) may be a viable treatment in the management of groin breakdown in selected patients when conventional therapy produces suboptimal results. PMID:15304156

Han, L Y; Schimp, V; Oh, J C; Ramirez, P T

2004-01-01

426

Non-commutative metric topology on matrix state space  

Microsoft Academic Search

We present an operator space version of Rieffel's theorem on the agreement of\\u000athe metric topology, on a subset of the Banach space dual of a normed space,\\u000afrom a seminorm with the weak*-topology. As an application we obtain a\\u000anecessary and sufficient condition for the matrix metric from an unbounded\\u000aFredholm module to give the BW-topology on the matrix

Wei Wu

2005-01-01

427

Design and operation of a 70 GHz second harmonic four cavity gyroklystron for radar applications  

Microsoft Academic Search

Summary form only given. In this paper, we present the application of this frequency-doubling technology to an existing first harmonic gyroklystron which has been under investigation at the Naval Research Laboratory. This system has been successfully operated with from 2-5 cavities. In a two cavity system, a peak power of 210 kW was achieved near 35 GHz with 37% efficiency

M. Walter; W. Lawson; J. P. Calame; M. Garven; V. L. Granatstein

1999-01-01

428

Applications for Mission Operations Using Multi-agent Model-based Instructional Systems with Virtual Environments  

NASA Technical Reports Server (NTRS)

This viewgraph presentation provides an overview of past and possible future applications for artifical intelligence (AI) in astronaut instruction and training. AI systems have been used in training simulation for the Hubble Space Telescope repair, the International Space Station, and operations simulation for the Mars Exploration Rovers. In the future, robots such as may work as partners with astronauts on missions such as planetary exploration and extravehicular activities.

Clancey, William J.

2004-01-01

429

High-Performance Low Operation Power Transistor for 45nm Node Universal Applications  

Microsoft Academic Search

High-performance low operation power (LOP) transistors were developed for 45nm node universal applications. A high uniaxial strain and low resistance NiSi technique, enhanced by a slit under the slim and high Young's modulus (YM) offset spacer covered with dual stress liner (DSL), were used for electron and hole mobility enhancement and parasitic resistance (Rsd) reduction. The junction profile was also

M. Shima; K. Okabe; A. Yamaguchi; T. Sakoda; K. Kawamura; S. Pidin; M. Okuno; T. Owada; K. Sugimoto; J. Ogura; H. Kokura; H. Morioka; T. Watanabe; T. Isome; K. Okoshi; T. Mori; Y. Hayami; H. Minakata; A. Hatada; Y. Shimamune; A. Katakami; H. Ota; T. Sakuma; T. Miyashita; K. Hosaka; H. Fukutome; N. Tamura; T. Aoyama; K. Sukegawa; M. Nakaishi; S. Fukuyama; S. Nakai; M. Kojima; S. Sato; M. Miyajima; K. Hashimoto; T. Sugii

2006-01-01

430

Operation and application of a laser mass analyser (LASMA) for multielement analysis  

Microsoft Academic Search

The design and the operation of the LASMA instrument combining laser ablation with time-of-flight mass analysis is briefly\\u000a described. The application to the analysis of multielement metal samples and non-conducting powder mixtures of known composition\\u000a reveals the LASMA technique to be a semi-quantitative method for elemental bulk analysis with a detection limit around 50\\u000a ?g\\/g in a mass range up

D. M. Woll; M. Wahl; H. Oechsner

1999-01-01

431

Container Shipping: Operating System Support for I\\/O-Intensive Applications  

Microsoft Academic Search

We present an operating system facility for efficiently transferring very large volumes of data between multiple processes and I\\/O devices, benefitting I\\/O inten- sive applications such as multimedia (e.g. video and image) and scientific comput- ing. The execution of these programs often create an I\\/O pipeline , a set of processes that repeatedly carry out the following steps: a large

Joseph Pasquale; Eric W. Anderson; Keith Muller

1994-01-01

432

SAR-Derived coastal and marine applications: from research to operational products  

Microsoft Academic Search

The synthetic aperture radar (SAR) has now successfully demonstrated its capacity to uniquely provide valuable high-resolution information for coastal applications (oil-spill monitoring, ship detection, shallow-water bathymetry mapping, sea-ice monitoring, high-resolution wind fields, coastal wave fields). However, it appears that the operational use of SAR-derived products still remains limited, particularly in Europe. Although costs and sampling rate are often invoked to

Vincent Kerbaol; Fabrice Collard

2005-01-01

433

Matrix Algebra.  

National Technical Information Service (NTIS)

The purpose of this thesis is to develop a textbook which presents basic concepts of matrix algebra from a primarily computational perspective, for an introductory course in matrix algebra at the Naval Postgraduate School (NPS). The need for an introducto...

S. A. Rife

1996-01-01

434

A phase-synchronization and random-matrix based approach to multichannel time-series analysis with application to epilepsy  

NASA Astrophysics Data System (ADS)

We present a general method to analyze multichannel time series that are becoming increasingly common in many areas of science and engineering. Of particular interest is the degree of synchrony among various channels, motivated by the recognition that characterization of synchrony in a system consisting of many interacting components can provide insights into its fundamental dynamics. Often such a system is complex, high-dimensional, nonlinear, nonstationary, and noisy, rendering unlikely complete synchronization in which the dynamical variables from individual components approach each other asymptotically. Nonetheless, a weaker type of synchrony that lasts for a finite amount of time, namely, phase synchronization, can be expected. Our idea is to calculate the average phase-synchronization times from all available pairs of channels and then to construct a matrix. Due to nonlinearity and stochasticity, the matrix is effectively random. Moreover, since the diagonal elements of the matrix can be arbitrarily large, the matrix can be singular. To overcome this difficulty, we develop a random-matrix based criterion for proper choosing of the diagonal matrix elements. Monitoring of the eigenvalues and the determinant provides a powerful way to assess changes in synchrony. The method is tested using a prototype nonstationary noisy dynamical system, electroencephalogram (scalp) data from absence seizures for which enhanced cortico-thalamic synchrony is presumed, and electrocorticogram (intracranial) data from subjects having partial seizures with secondary generalization for which enhanced local synchrony is similarly presumed.

Osorio, Ivan; Lai, Ying-Cheng

2011-09-01

435

Development of dual-fiber-reinforced glass-matrix composites for structural space-based applications. Final report, 14 March 1988-14 March 1990  

Microsoft Academic Search

The goal of the program was to create high specific stiffness, zero thermal composites for structural applications in space by using dual fiber reinforcement approach. This approach consisted of adding large-diameter monofilaments as a secondary reinforcement to a pitch-based carbon fiber reinforces glass matrix composite. It was demonstrated that composite thermal expansion could be increased into the near-zero domain over

W. K. Treadway; K. M. Prewo

1990-01-01

436

Formation of low surface energy separators with undercut structures via a full-solution process and its application in inkjet printed matrix of polymer light-emitting diodes  

Microsoft Academic Search

In this paper, low surface energy separators with undercut structures were fabricated through a full-solution process. These low surface energy separators are more suitable for application in inkjet printed passive-matrix displays of polymer light-emitting diodes. A patterned PS film was formed on the P4VP\\/photoresist film by microtransfer printing firstly. Patterned Au-coated Ni film was formed on the uncovered P4VP\\/photoresist film

Rubo Xing; Tengling Ye; Yan Ding; Dongge Ma; Yanchun Han

2009-01-01

437

Effects of neutral particle beam on nano-crystalline silicon thin films, with application to thin film transistor backplane for flexible active matrix organic light emitting diodes  

Microsoft Academic Search

A novel deposition process for nano-crystalline silicon (nc-Si) thin films was developed using neutral beam assisted chemical vapor deposition (NBaCVD) technology for the application of the thin film transistor (TFT) backplane of flexible active matrix organic light emitting diode (AMOLED). During the formation of a nc-Si thin film, the energetic particles enhance nano-sized crystalline rather microcrystalline Si in thin films.

Jin Nyoung Jang; Byoung Chul Song; Dong Hyeok Lee; Suk Jae Yoo; Bonju Lee; MunPyo Hong

2011-01-01

438

Medical Matrix  

NSDL National Science Digital Library

Medical Matrix is a Web resource that offers a database of Internet clinical medicine resources. Medical Matrix categorizes resources by disease, specialty, and other interest areas. It is designed as a "home page" for a physician's or healthworker's computer. Medical Matrix is a project of the Internet Working Group of the American Medical Informatics Association.

439

Nonorthogonal orbital based N-body reduced density matrices and their applications to valence bond theory. I. Hamiltonian matrix elements between internally contracted excited valence bond wave functions  

NASA Astrophysics Data System (ADS)

In this series, the n-body reduced density matrix (n-RDM) approach for nonorthogonal orbitals and their applications to ab initio valence bond (VB) methods are presented. As the first paper of this series, Hamiltonian matrix elements between internally contracted VB wave functions are explicitly provided by means of nonorthogonal orbital based RDM approach. To this end, a more generalized Wick's theorem, called enhanced Wick's theorem, is presented both in arithmetical and in graphical forms, by which the deduction of expressions for the matrix elements between internally contracted VB wave functions is dramatically simplified, and the matrix elements are finally expressed in terms of tensor contractions of electronic integrals and n-RDMs of the reference VB self-consistent field wave function. A string-based algorithm is developed for the purpose of evaluating n-RDMs in an efficient way. Using the techniques presented in this paper, one is able to develop new methods and efficient algorithms for nonorthogonal orbital based many-electron theory much easier than by use of the first quantized formulism.

Chen, Zhenhua; Chen, Xun; Wu, Wei

2013-04-01

440

Nonorthogonal orbital based N-body reduced density matrices and their applications to valence bond theory. I. Hamiltonian matrix elements between internally contracted excited valence bond wave functions.  

PubMed

In this series, the n-body reduced density matrix (n-RDM) approach for nonorthogonal orbitals and their applications to ab initio valence bond (VB) methods are presented. As the first paper of this series, Hamiltonian matrix elements between internally contracted VB wave functions are explicitly provided by means of nonorthogonal orbital based RDM approach. To this end, a more generalized Wick's theorem, called enhanced Wick's theorem, is presented both in arithmetical and in graphical forms, by which the deduction of expressions for the matrix elements between internally contracted VB wave functions is dramatically simplified, and the matrix elements are finally expressed in terms of tensor contractions of electronic integrals and n-RDMs of the reference VB self-consistent field wave function. A string-based algorithm is developed for the purpose of evaluating n-RDMs in an efficient way. Using the techniques presented in this paper, one is able to develop new methods and efficient algorithms for nonorthogonal orbital based many-electron theory much easier than by use of the first quantized formulism. PMID:23635123

Chen, Zhenhua; Chen, Xun; Wu, Wei

2013-04-28

441

A Charge-Pump Active-Matrix Pixel Driving Method for Organic Light-Emitting Diode Display Applications  

NASA Astrophysics Data System (ADS)

A new pixel driving method is proposed for the implementation of a high information content organic light-emitting diode (OLED) flat-panel display (FPD). The new charge-pump active-matrix pixel driver consists only of a capacitance and a rectifying diode. Since no thin-film transistor (TFT) is needed in the new circuit, the manufacturing process for the fabrication of an OLED display panel can be greatly simplified compared to the one using the conventional TFT-based active-matrix pixel drivers. The new driver not only supplies a continuous current to the OLED throughout the whole period of panel scanning like the conventional TFT-based active-matrix driver, but also provides a highly linear gray-scale control through a pure digital manner similar to a pulse-width modulation (PWM) method.

Seo, Jong-Wook; Kim, Hanbyul; Kim, Bongok; Kim, Youngkwan

2002-12-01

442

In Situ Synthesis Aluminum Borate Whiskers Reinforced TiB2 Matrix Composites for Application in Aluminum Reduction Cells  

NASA Astrophysics Data System (ADS)

The TiB2 matrix ceramics reinforced by aluminum borate whiskers (Al18B4O33 w) had been prepared by the pressureless sintering method. The mechanical properties and densification behavior of the TiB2 matrix ceramics were investigated. The results showed that Al18B4O33 w was in situ synthesized by the reaction of boehmite (AlOOH) and TiB2 powders during the sintering process. Increasing the sintering temperature had benefited for densification of the TiB2 matrix ceramics. Al18B4O33 w could increase the flexural strength and Vicker's hardness. It is obtained that the maximum value Vicker's hardness with 1.81 GPa and flexural strength with 82 MPa for samples sintered at 1600°C.

Zhang, Gang; Yang, Jianhong

2013-11-01