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1

Jargonial-Obfuscation(J-O) DISambiguation Elimination via Siegel-Baez Cognition Category-Semantics(C-S) in Siegel FUZZYICS=CATEGORYICS (Son of TRIZ)/(F=C) Tabular List-Format Dichotomy Truth-Table Matrix Analytics  

NASA Astrophysics Data System (ADS)

NOT "philosophy" per se but raising serious salient Arnol'd [Huygens and Barrow, Newton and Hooke(96)] questions begged is Rota empiricism Husserl VS. Frege maths-objects Dichotomy controversy: Hill-Haddock[Husserl or Frege?(00)]as manifestly-demonstrated by Hintikka[B.U.]-Critchey[Derrida Deconstruction Ethics(78)] deconstruction; Altshuler TRIZ; Siegel F=C/C-S; Siegel-Baez(UCR) Cognition C-S = "Category-theory "+" Cognitive-Semantics[Wierzbica-Langacker-Lakoff-Nunez[Where Maths Comes From(00)]-Fauconnier-Turner[Blending(98)]-Coulson[Semantic-Leaps (00)

Siegel, Carl Ludwig; Carl-Ludwig Siegel, Edward

2011-03-01

2

Efficient Tabular LR Parsing  

Microsoft Academic Search

We give a new treatment of tabular LR parsing, which is an alternative to Tomita's generalized LR algorithm. The advantage is twofold. Firstly, our treatment is conceptually more attractive because it uses simpler concepts, such as grammar transformations and standard tabulation techniques also know as . Secondly, the static and dynamic complexity of parsing, both in space and time, is

Mark-Jan Nederhof; Giorgio Satta

1996-01-01

3

JSparklines: Making tabular proteomics data come alive.  

PubMed

Perhaps the most common way of presenting proteomics data, and indeed life sciences data in general, is by using some form of tabular data. And while tables can be very informative and contain lots of information, the format can be challenging to interpret visually. An elegant and efficient solution is to extend the textual and numerical information with an additional visual layer, referred to as sparklines, making it intuitive to draw inferences about the properties of the underlying data. We here present a free and open source Java library called JSparklines (http://jsparklines.googlecode.com) that allows straightforward addition of a substantial list of customizable sparklines to tabular data representations, and we show examples of how these sparklines greatly simplify the interpretation of the tabular data. PMID:25422159

Barsnes, Harald; Vaudel, Marc; Martens, Lennart

2015-04-01

4

Comprehensibility Improvement of Tabular Knowledge Bases  

E-print Network

to be a serious burden for the knowledge engineers who must manage knowledge bases. Purpose of this research and only method to improve the comprehensibility of a knowledge base was to simplify the conceptComprehensibility Improvement of Tabular Knowledge Bases Atsushi Sugiuray Maximilian yC&C Systems

Riesenhuber, Maximilian

5

Fast Mining of Massive Tabular Data via Approximate Distance Computations  

Microsoft Academic Search

Tabular data abound in many data stores: traditional re- lational databases store tables, and new applications also generate massive tabular datasets. For example, consider the geographic distribution of cell phone traffic at different base stations across the country or the evolution of traffic at Internet routers over time . Detecting similarity patterns in such data sets (e.g., which geographic regions

Graham Cormode; Piotr Indyk; Nick Koudas; S. Muthukrishnan

2002-01-01

6

BayesDB : querying the probable implications of tabular data  

E-print Network

BayesDB, a Bayesian database table, lets users query the probable implications of their tabular data as easily as an SQL database lets them query the data itself. Using the built-in Bayesian Query Language (BQL), users ...

Baxter, Jay

2014-01-01

7

A new model for tabular-type uranium deposits  

USGS Publications Warehouse

Tabular-type uranium deposits occur as tabular, originally subhorizontal bodies entirely within reduced fluvial sandstones of Late Silurian age or younger. This paper proposes that belts of tabular-type uranium deposits formed in areas of mixed local and regional groundwater discharge shortly after deposition of the host sediments. The general characteristics of tabular-type uranium deposits indicate that their essential feature was the formation at a density-stratified ground-water interface in areas of local and regional ground-water discharge. Reconstruction of the paleohydrogeology is the key to understanding the formation of these deposits. Geologic ground-water controls that favor discharge, such as the pinch-out of major aquifers, are also favorable for uranium ore. The combination of topographic and geologic features that both cause discharge is most favorable for ore deposition. -from Author

Sanford, R.F.

1992-01-01

8

Min-cut segmentation of cursive handwriting in tabular documents  

NASA Astrophysics Data System (ADS)

Handwritten tabular documents, such as census, birth, death and marriage records, contain a wealth of information vital to genealogical and related research. Much work has been done in segmenting freeform handwriting, however, segmentation of cursive handwriting in tabular documents is still an unsolved problem. Tabular documents present unique segmentation challenges caused by handwriting overlapping cell-boundaries and other words, both horizontally and vertically, as "ascenders" and "descenders" overlap into adjacent cells. This paper presents a method for segmenting handwriting in tabular documents using a min-cut/max-flow algorithm on a graph formed from a distance map and connected components of handwriting. Specifically, we focus on line, word and first letter segmentation. Additionally, we include the angles of strokes of the handwriting as a third dimension to our graph to enable the resulting segments to share pixels of overlapping letters. Word segmentation accuracy is 89.5% evaluating lines of the data set used in the ICDAR2013 Handwriting Segmentation Contest. Accuracy is 92.6% for a specific application of segmenting first and last names from noisy census records. Accuracy for segmenting lines of names from noisy census records is 80.7%. The 3D graph cutting shows promise in segmenting overlapping letters, although highly convoluted or overlapping handwriting remains an ongoing challenge.

Davis, Brian L.; Barrett, William A.; Swingle, Scott D.

2015-01-01

9

The application of short rockbolts in ultradeep tabular stoping  

Microsoft Academic Search

Most rock related fatalities and injuries in South African gold mines occur in the stope face area. These mines generally do not use rockbolts to support this area. This paper describes short rockbolt applications in the stope face area in a narrow tabular ultradeep Carbon Leader stope. The project began with the geotechnical definition of the generic Carbon Leader Reef

M. K. C. Roberts?; R. A. Lamos; S. K. Murphy

2004-01-01

10

A Distribution-Free Tabular CUSUM Chart for Autocorrelated Data  

E-print Network

of an autocorrelated process. The chart's average run length (ARL) is approximated by gener- alizing Siegmund's ARL. The new chart is compared with other distribution-free procedures using stationary test processes with both normal and nonnormal marginals. Key Words: Statistical Process Control; Tabular CUSUM Chart

Kim, Seong-Hee

11

Network-Based Visual Analysis of Tabular Data  

ERIC Educational Resources Information Center

Tabular data is pervasive in the form of spreadsheets and relational databases. Although tables often describe multivariate data without explicit network semantics, it may be advantageous to explore the data modeled as a graph or network for analysis. Even when a given table design conveys some static network semantics, analysts may want to look…

Liu, Zhicheng

2012-01-01

12

MCNP/X TRANSPORT IN THE TABULAR REGIME  

SciTech Connect

The authors review the transport capabilities of the MCNP and MCNPX Monte Carlo codes in the energy regimes in which tabular transport data are available. Giving special attention to neutron tables, they emphasize the measures taken to improve the treatment of a variety of difficult aspects of the transport problem, including unresolved resonances, thermal issues, and the availability of suitable cross sections sets. They also briefly touch on the current situation in regard to photon, electron, and proton transport tables.

HUGHES, H. GRADY [Los Alamos National Laboratory

2007-01-08

13

ERDDAP - A Brokering Data Server for Gridded and Tabular Datasets  

NASA Astrophysics Data System (ADS)

ERDDAP is an open-source data server that gives users a simple, consistent way (OPeNDAP requests) to download subsets of scientific datasets in common file formats and make graphs and maps. ERDDAP is a middle man (a broker) between users and various remote data services (and also local databases and files). Using just two internal structures for datasets (multi-dimensional grids and database-like tables) makes the problem manageable and also works well with OPeNDAP's projection constraints (for gridded data) and selection constraints (for tabular/sequence data).;

Simons, R. A.; Mendelssohn, R.

2012-12-01

14

Supporting awareness through collaborative brushing and linking of tabular data.  

PubMed

Maintaining an awareness of collaborators' actions is critical during collaborative work, including during collaborative visualization activities. Particularly when collaborators are located at a distance, it is important to know what everyone is working on in order to avoid duplication of effort, share relevant results in a timely manner and build upon each other's results. Can a person's brushing actions provide an indication of their queries and interests in a data set? Can these actions be revealed to a collaborator without substantially disrupting their own independent work? We designed a study to answer these questions in the context of distributed collaborative visualization of tabular data. Participants in our study worked independently to answer questions about a tabular data set, while simultaneously viewing brushing actions of a fictitious collaborator, shown directly within a shared workspace. We compared three methods of presenting the collaborator's actions: brushing & linking (i.e. highlighting exactly what the collaborator would see), selection (i.e. showing only a selected item), and persistent selection (i.e. showing only selected items but having them persist for some time). Our results demonstrated that persistent selection enabled some awareness of the collaborator's activities while causing minimal interference with independent work. Other techniques were less effective at providing awareness, and brushing & linking caused substantial interference. These findings suggest promise for the idea of exploiting natural brushing actions to provide awareness in collaborative work. PMID:24051785

Hajizadeh, Amir Hossein; Tory, Melanie; Leung, Rock

2013-12-01

15

The origin and significance of large, tabular dunite bodies in the Trinity peridotite, northern California  

Microsoft Academic Search

Kilometer-sized, tabular dunite bodies are contained within harzburgite, lherzolite and plagioclase lherzolite host rocks in the Trinity peridotite, northern California. An igneous origin for the dunite by crystal fractionation of olivine from a melt is suggested by their tabular shapes, clots of poikilitic clinopyroxene grains, chromite pods, and by analogy to dunite bodies in the Samail and Vourinos ophiolites (Hopson

James E. Quick

1982-01-01

16

Consistent thermodynamic derivative estimates for tabular equations of state.  

NASA Astrophysics Data System (ADS)

A valid fluid equation of state must satisfy the thermodynamic differential conditions of consistency (derivation from a free energy) and stability (positive sound speed squared). Typical software interfaces to tabular equations of state based on polynomial or rational interpolants compute derivatives of pressure and energy and may enforce the stability conditions, but do not enforce the consistency condition and its derivatives, which is important for the computation of dimensionless quantities associated with more sensitive artificial viscosities and Riemann solvers that accurately model shock structure in regions near phase transitions. We describe a new type of table interface derived from a constrained local least squares regression technique. Application to several SESAME tables shows the consistency condition can be satisfied to round-off with third-order accuracy. An improvement of 14 orders of magnitude over conventional derivatives is demonstrated, although the new method is two orders of magnitude slower, due to solving an 11-dimensional nonlinear system. The new approach can be used to construct consistent and stable tables of derivatives, however.

Dilts, Gary

2005-07-01

17

Consistent thermodynamic derivative estimates for tabular equations of state  

NASA Astrophysics Data System (ADS)

A valid fluid equation of state (EOS) must satisfy the thermodynamic conditions of consistency (derivation from a free energy) and stability (positive sound speed squared). Numerical simulations of compressible fluid flow for realistic materials require a tabular EOS, but typical software interfaces to such tables based on polynomial or rational interpolants may enforce the stability conditions, but do not enforce the consistency condition and its derivatives. The consistency condition is important for the computation of various dimensionless parameters of an EOS that may involve derivatives of up to second order which are important for the development of more sensitive artificial viscosities and Riemann solvers that accurately model shock structure in regions near phase transitions. We describe a table interface based on the tuned regression method, which is derived from a constrained local least-squares regression technique. It is applied to several SESAME EOS showing how the consistency and stability conditions can be satisfied to round-off while computing first and second derivatives with demonstrated second-order convergence. An improvement of 14 orders of magnitude over conventional derivatives is demonstrated, although the method is apparently two orders of magnitude slower, due to the fact that every evaluation requires solving an 11-dimensional nonlinear system. Application is made to the computation of the fundamental derivative.

Dilts, Gary A.

2006-06-01

18

Geosites inventory of the northwestern Tabular Middle Atlas of Morocco  

NASA Astrophysics Data System (ADS)

Across the northwestern Tabular Middle Atlas of Morocco there are many examples of landscapes, rocks and fossils that provide key evidence of a particular moment or period in Earth history. Such Earth heritage sites are important for educating the general public in environmental matters. They also serve as tools for demonstrating sustainable development and for illustrating methods of site conservation as well as remembering that rocks, minerals, fossils, soils, landforms form an integral part of the natural world. The significance of certain sites for aesthetic or tourism reasons is obvious. There are numerous geosites, which could contribute to effective exploitation of geotourism, often in conjunction with ecotourism. The strategy employed to such sites involves close consultation with all communities in the vicinity of the respective geosite and is not only aimed at tourism and education, but also at sustainable improvement of the infrastructure of the people of this area. Geological heritage sites, properly managed, can generate employment and new economic activities, especially in regions in need of new or additional sources of income.

El Wartiti, Mohamed; Malaki, Amina; Zahraoui, Mohamed; El Ghannouchi, Abdelilah; di Gregorio, Felice

2008-07-01

19

Analyzing Tabular and State-Transition Requirements Specifications in PVS  

NASA Technical Reports Server (NTRS)

We describe PVS's capabilities for representing tabular specifications of the kind advocated by Parnas and others, and show how PVS's Type Correctness Conditions (TCCs) are used to ensure certain well-formedness properties. We then show how these and other capabilities of PVS can be used to represent the AND/OR tables of Leveson and the Decision Tables of Sherry, and we demonstrate how PVS's TCCs can expose and help isolate errors in the latter. We extend this approach to represent the mode transition tables of the Software Cost Reduction (SCR) method in an attractive manner. We show how PVS can check these tables for well-formedness, and how PVS's model checking capabilities can be used to verify invariants and reachability properties of SCR requirements specifications, and inclusion relations between the behaviors of different specifications. These examples demonstrate how several capabilities of the PVS language and verification system can be used in combination to provide customized support for specific methodologies for documenting and analyzing requirements. Because they use only the standard capabilities of PVS, users can adapt and extend these customizations to suit their own needs. Those developing dedicated tools for individual methodologies may find these constructions in PVS helpful for prototyping purposes, or as a useful adjunct to a dedicated tool when the capabilities of a full theorem prover are required. The examples also illustrate the power and utility of an integrated general-purpose system such as PVS. For example, there was no need to adapt or extend the PVS model checker to make it work with SCR specifications described using the PVS TABLE construct: the model checker is applicable to any transition relation, independently of the PVS language constructs used in its definition.

Owre, Sam; Rushby, John; Shankar, Natarajan

1997-01-01

20

Do tabular corals constitute keystone structures for fishes on coral reefs?  

NASA Astrophysics Data System (ADS)

This study examined the changes in community composition of reef fishes by experimentally manipulating the availability of shelter provided by tabular structures on a mid-shelf reef on the Great Barrier Reef. At locations where access to tabular corals ( Acropora hyacinthus and Acropora cytherea) was excluded, a rapid and sustained reduction in the abundance of large reef fishes occurred. At locations where tabular structure was added, the abundance and diversity of large reef fishes increased and the abundance of small reef fishes tended to decrease, although over a longer time frame. Based on their response to changes in the availability of tabular structures, nine families of large reef fishes were separated into three categories; designated as obligate, facultative or non-structure users. This relationship may relate to the particular ecological demands of each family, including avoidance of predation and ultraviolet radiation, access to feeding areas and reef navigation. This study highlights the importance of tabular corals for large reef fishes in shallow reef environments and provides a possible mechanism for local changes in the abundance of reef fishes following loss of structural complexity on coral reefs. Keystone structures have a distinct structure and disproportionate effect on their ecosystem relative to their abundance, as such the result of this study suggests tabular corals may constitute keystone structures on shallow coral reefs.

Kerry, J. T.; Bellwood, D. R.

2015-03-01

21

Multiple Foci Drill-Down through Tuple and Attribute Polyarchies in Tabular Data  

E-print Network

Multiple Foci Drill-Down through Tuple and Attribute Polyarchies in Tabular Data Nathan Conklin user guided drill-down of polyarchical metadata. This metadata describes multiple hierarchical of visualizations at each level of the hierarchy. Breakdown Visualization allows users to drill-down a single

22

Automated recognition and extraction of tabular fields for the indexing of census records  

NASA Astrophysics Data System (ADS)

We describe a system for indexing of census records in tabular documents with the goal of recognizing the content of each cell, including both headers and handwritten entries. Each document is automatically rectified, registered and scaled to a known template following which lines and fields are detected and delimited as cells in a tabular form. Whole-word or whole-phrase recognition of noisy machine-printed text is performed using a glyph library, providing greatly increased efficiency and accuracy (approaching 100%), while avoiding the problems inherent with traditional OCR approaches. Constrained handwriting recognition results for a single author reach as high as 98% and 94.5% for the Gender field and Birthplace respectively. Multi-author accuracy (currently 82%) can be improved through an increased training set. Active integration of user feedback in the system will accelerate the indexing of records while providing a tightly coupled learning mechanism for system improvement.

Clawson, Robert; Bauer, Kevin; Chidester, Glen; Pohontsch, Milan; Kennard, Douglas; Ryu, Jongha; Barrett, William

2013-01-01

23

The origin and significance of large, tabular dunite bodies in the Trinity peridotite, northern California  

NASA Astrophysics Data System (ADS)

Kilometer-sized, tabular dunite bodies are contained within harzburgite, lherzolite and plagioclase lherzolite host rocks in the Trinity peridotite, northern California. An igneous origin for the dunite by crystal fractionation of olivine from a melt is suggested by their tabular shapes, clots of poikilitic clinopyroxene grains, chromite pods, and by analogy to dunite bodies in the Samail and Vourinos ophiolites (Hopson et al. 1981; Harkins et al. 1980; Moores 1969). However, structures and systematic variations in mineralogy and mineral chemistry suggest that at least the marginal few meters of the bodies are residues produced by extraction of a basaltic component from a plagioclase lherzolite protolith. A model is suggested in which a picritic melt ascended through the upper mantle in vertically oriented channels. Part of the dunite in the tabular bodies was produced by fractional crystallization of olivine from the melt. Additional dunite at the margins of the bodies was formed by extraction of a basaltic component from plagioclase lherzolite wall-rocks during partial assimilation by the picritic melt. The latter process is similar to the “wall-rock reaction” discussed by Green and Ringwood (1967) and is essentially zone refining of the the mantle wall rocks by the migrating melt. It is significant because it suggests a mechanism in addition to fractional crystallization for enrichment of incompatible elements in basalts.

Quick, James E.

1982-03-01

24

9 CFR 205.102 - Name of person subjecting a farm product to a security interest, on EFS and master list-format.  

Code of Federal Regulations, 2010 CFR

9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Name of person subjecting a farm product to a security interest, on EFS...list-format. 205.102 Section 205.102 Animals and Animal Products GRAIN...

2010-01-01

25

Technical Report: CSVM format for scientific tabular data CSVM specification (CSVM-1): concept and design, guidelines, parsers.  

E-print Network

for database management systems (cf. NoSQL4 ). Later the work was extended in other scientific fields Separated Values 1 ) is a de facto industry standard to exchange tabular data from spreadsheets or databases

Paris-Sud XI, Université de

26

A quantitative model of ground-water flow during formation of tabular sandstone uranium deposits  

USGS Publications Warehouse

Presents a quantitative simulation of regional groundwater flow during uranium deposition in the Westwater Canyon Member and Jackpile Sandstone Member of the Upper Jurassic Morrison Formation in the San Juan basin. Topographic slope, shoreline position, and density contrasts in the lake and pore fluids controlled the directions of flow and recharge-discharge areas. The most important results for uranium ore deposit formation are that regional groundwater discharged throughout the basin, regional discharge was concentrated along the shore line or playa margin, flow was dominantly gravity driven, and compaction dewatering was negligible. A strong association is found between the tabular sandstone uranium deposits and major inferred zones of mixed local and regional groundwater discharge. -from Author

Sanford, R.F.

1994-01-01

27

CAP: A Computer Code for Generating Tabular Thermodynamic Functions from NASA Lewis Coefficients  

NASA Technical Reports Server (NTRS)

For several decades the NASA Glenn Research Center has been providing a file of thermodynamic data for use in several computer programs. These data are in the form of least-squares coefficients that have been calculated from tabular thermodynamic data by means of the NASA Properties and Coefficients (PAC) program. The source thermodynamic data are obtained from the literature or from standard compilations. Most gas-phase thermodynamic functions are calculated by the authors from molecular constant data using ideal gas partition functions. The Coefficients and Properties (CAP) program described in this report permits the generation of tabulated thermodynamic functions from the NASA least-squares coefficients. CAP provides considerable flexibility in the output format, the number of temperatures to be tabulated, and the energy units of the calculated properties. This report provides a detailed description of input preparation, examples of input and output for several species, and a listing of all species in the current NASA Glenn thermodynamic data file.

Zehe, Michael J.; Gordon, Sanford; McBride, Bonnie J.

2001-01-01

28

CAP: A Computer Code for Generating Tabular Thermodynamic Functions from NASA Lewis Coefficients. Revised  

NASA Technical Reports Server (NTRS)

For several decades the NASA Glenn Research Center has been providing a file of thermodynamic data for use in several computer programs. These data are in the form of least-squares coefficients that have been calculated from tabular thermodynamic data by means of the NASA Properties and Coefficients (PAC) program. The source thermodynamic data are obtained from the literature or from standard compilations. Most gas-phase thermodynamic functions are calculated by the authors from molecular constant data using ideal gas partition functions. The Coefficients and Properties (CAP) program described in this report permits the generation of tabulated thermodynamic functions from the NASA least-squares coefficients. CAP provides considerable flexibility in the output format, the number of temperatures to be tabulated, and the energy units of the calculated properties. This report provides a detailed description of input preparation, examples of input and output for several species, and a listing of all species in the current NASA Glenn thermodynamic data file.

Zehe, Michael J.; Gordon, Sanford; McBride, Bonnie J.

2002-01-01

29

Tabular water properties interface for Hydra-TH : CASL THM.CFD.P6.03 milestone report.  

SciTech Connect

Completion of the CASL L3 milestone THM.CFD.P6.03 provides a tabular material properties capability to the Hydra code. A tabular interpolation package used in Sandia codes was modified to support the needs of multi-phase solvers in Hydra. Use of the interface is described. The package was released to Hydra under a government use license. A dummy physics was created in Hydra to prototype use of the interpolation routines. Finally, a test using the dummy physics verifies the correct behavior of the interpolation for a test water table. 3

Carpenter, John H.; Belcourt, Noel

2013-04-01

30

The table lens: merging graphical and symbolic representations in an interactive focus+context visualization for tabular information  

Microsoft Academic Search

We present a new visualization, called the Table Lens, for visualizing and making sense of large tables. The visual- ization uses a focus+context (fisheye) technique that works effectively on tabular information because it allows display of crucial label information and multiple distal focal areas. In addition, a graphical mapping scheme for depicting table contents has been developed for the most

Ramana Rao; Stuart K. Card

1994-01-01

31

Tracking large tabular icebergs using the SeaWinds Ku-band microwave scatterometer  

NASA Astrophysics Data System (ADS)

Knowledge of iceberg locations is important for safety reasons as well as for understanding many geophysical and biological processes. Originally designed to measure wind speed and direction over the ocean, SeaWinds is a microwave scatterometer that operates at 13.4 GHz (Ku-band) on the QuikSCAT satellite. Radar measurements from SeaWinds are collected and processed on a daily basis using resolution-enhancement techniques to produce daily radar images. Because icebergs scatter microwave energy more than sea ice and sea water, icebergs are detected as high-backscatter targets surrounded by lower-backscatter regions in daily SeaWinds images. As a result, iceberg positions are determined in real-time and a time-series of iceberg positions is maintained in an Antarctic iceberg database by Brigham Young University's Microwave Earth Remote Sensing (MERS) laboratory. Since SeaWinds operates independent of both solar illumination and cloud cover and has a large daily spatial coverage, this paper demonstrates that SeaWinds is an excellent platform to detect and track large tabular icebergs. These icebergs are generally larger than 5 km and are typically characterized as a rough ice plateau above the surrounding sea water or sea ice. The number of icebergs tracked in the MERS Antarctic iceberg database is found to be generally greater than the number of icebergs tracked by the National Ice Center. The movement patterns of all icebergs detected by SeaWinds are also analyzed and 90% of icebergs are found to travel a counter-clockwise path around Antarctica and accumulate in the Weddell and Scotia Seas. Iceberg detection and tracking is demonstrated via multiple case studies that highlight icebergs C-19a and A-22a using the MERS database and through real-time operational support of the 2005, 2008, and 2009 NSF Antarctic cruises. Iceberg positions are validated by using collocated high-resolution satellite imagery and by navigating the NSF ships to physically intercept several large tabular icebergs in the Weddell and Scotia Seas.

Stuart, K. M.; Long, D. G.

2011-06-01

32

Geochemical properties of the water-snow-ice complexes in the area of Shokalsky glacier, Novaya Zemlya, in relation to tabular ground-ice formation  

Microsoft Academic Search

Tabular (massive) ground ice in periglacial areas of the Russian Arctic (Barents and Kara Sea coasts) is considered to be a remnant of past glacial epochs and is thus used as proof of the glacial extent. In this paper, we argue that the origin of these tabular ice bodies, which can be used as archives of specific climatic conditions and

M. O. Leibman; S. M. Arkhipov; D. D. Perednya; A. S. Savvichev; B. G. Vanshtein; H. W. Hubberten

2005-01-01

33

Genesis of the tabular-type vanadium-uranium deposits of the Henry Basin, Utah  

USGS Publications Warehouse

Tabular-type vanadium-uranium deposits occur in fluvial sandstones of the Salt Wash Member of the Morrison Formation of Late Jurassic age The mineralized intervals and the weakly mineralized lateral extensions are bounded both above and below by zones rich in dolomite cement. Carbon isotope values of dolomite cements indicate that at least two sources of carbon existed. One source appears to be the same as that which formed the bedded carbonates in the evaporites in the Tidwell Member of the Morrison Formation stratigraphically below the mineralized interval. The second carbon source is typical of terrestrially deposited carbonates generally associated with meteoric water-dominated environments. Oxygen isotope values of these dolomites show the same trend of isotopically light values above the mineralized interval and isotopically heavier values in and below that interval; they indicate that two isotopically distinct fluids were involved in the mineralizing process. Some aspects of the origin of gangue and ore phases are explainable on the basis of processes which occurred solely within the saline fluid, but key aspects of ore genesis involved the interaction of the saline and meteoric waters. It is postulated that the solution interface migrated vertically within the stratigraphic section. -from Authors

Northrop, H.R.; Goldhaber, M.B.

1990-01-01

34

Calcium-doped ceria/titanate tabular functional nanocomposite by layer-by-layer coating method  

SciTech Connect

Ca-doped ceria (CDC)/tabular titanate (K{sub 0.8}Li{sub 0.27}Ti{sub 1.73}O{sub 4}, TT) UV-shielding functional nanocomposite with fairly uniform CDC coating layers was prepared through a polyelectrolyte-associated layer-by-layer (LbL) coating method. TT with lepidocrocite-like layered structure was used as the substrate, poly (diallyldimethylammonium chloride) (PDDA) was used as a coupling agent, CDC nanoparticles were used as the main UV-shielding component. CDC/TT nanocomposites with various coating layers of CDC were obtained through a multistep coating process. The phases were studied by X-ray diffraction. The morphology and coating quality were studied by scanning electron microscopy and element mapping of energy dispersive X-ray analysis. The oxidation catalytic activity, UV-shielding ability and using comfort were characterized by Rancimat test, UV-vis spectra and dynamic friction test, respectively. CDC/TT nanocomposites with low oxidation catalytic activity, high UV-shielding ability and good using comfort were finally obtained. - Graphical abstract: Through the control of surface charge of particles calcium-doped ceria/titanate composites with low oxidation catalytic activity, higher UV-shielding ability and excellent comfort was obtained by a facile layer-by-layer coating method.

Liu, Xiang W., E-mail: lxwluck@gmail.co [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 980-8577 Suita (Japan); Devaraju, M.K.; Yin, Shu; Sato, Tsugio [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 980-8577 Suita (Japan)

2010-07-15

35

Combining tabular, rule-based, and procedural knowledge in computer-based guidelines for childhood immunization.  

PubMed

IMM/Serve is a computer program which implements the clinical guidelines for childhood immunization. IMM/Serve accepts as input a child's immunization history. It then indicates which vaccinations are due and which vaccinations should be scheduled next. The clinical guidelines for immunization are quite complex and are modified quite frequently. As a result, it is important that IMM/Serve's knowledge be represented in a format that facilitates the maintenance of that knowledge as the field evolves over time. To achieve this goal, IMM/Serve uses four representations for different parts of its knowledge base: (1) Immunization forecasting parameters that specify the minimum ages and wait-intervals for each dose are stored in tabular form. (2) The clinical logic that determines which set of forecasting parameters applies for a particular patient in each vaccine series is represented using if-then rules. (3) The temporal logic that combines dates, ages, and intervals to calculate recommended dates, is expressed procedurally. (4) The screening logic that checks each previous dose for validity is performed using a decision table that combines minimum ages and wait intervals with a small amount of clinical logic. A knowledge maintenance tool, IMM/Def, has been developed to help maintain the rule-based logic. The paper describes the design of IMM/Serve and the rationale and role of the different forms of knowledge used. PMID:9281329

Miller, P L; Frawley, S J; Sayward, F G; Yasnoff, W A; Duncan, L; Fleming, D W

1997-06-01

36

Ambient seismic, hydroacoustic, and flexural gravity wave noise on a tabular iceberg  

NASA Astrophysics Data System (ADS)

Cross correlation of ambient seismic noise between four seismographs on tabular iceberg C16, Ross Sea, Antarctica, reveals both the source and the propagation characteristics of signals associated with icebergs. We find that noise correlation functions computed from station data are asymmetric about zero time lag, and this indicates that noise observed on the iceberg originates primarily from a compact, localized source associated with iceberg collisions between C16 and a neighboring iceberg, B15A. We additionally find two, and possibly more, distinct phases of noise propagation. We believe that flexural gravity wave propagation dominates the low-frequency noise (>10 s period) and that hydroacoustic wave propagation in the water column between the ice and seabed appears to dominate high-frequency noise (>10 Hz). Faster seismic propagation dominates the intermediate band (2-6 Hz); however, we do not have sufficient data to characterize the wave mechanisms more precisely, e.g., by identifying distinct longitudinal and shear body waves and/or surface waves. Secular changes in the amplitude and timing of ambient noise correlations, e.g., a diurnal cycle and an apparent shift in the noise correlation of fast seismic modes between two periods of the deployment, allow us to speculate that ambient noise correlation analysis may be helpful in understanding the sources and environmental controls on iceberg-generated ocean noise as well as geometric properties (such as water column thickness) of subglacial lakes.

MacAyeal, Douglas R.; Wang, Yitan; Okal, Emile A.

2015-02-01

37

Dynamical Domain Tabular Collisional Radiative Equilibrium Radiation Transport Model for Argon Gas-Puff Z-Pinch Plasmas  

Microsoft Academic Search

Summary form only given. The proper treatment of the radiation transport in the multidimensional MHD simulations of large diameter argon gas-puff Z-pinch loads is essential in understanding and predicting accurately the dynamic evolution and the radiative emission characteristics of the plasmas. The tabular collisional radiative equilibrium (TCRE) radiation transport model represents a novel approach to the realistic self-consistent treatment of

Y. K. Chong; J. W. Thornhill; J. P. Apruzese; J. Davis; H. D. Minor

2005-01-01

38

Radon constrains the transit time of springs water at the border between tabular Middle Atlas and the Sais Basin (Morocco)  

Microsoft Academic Search

The tabular Middle Atlas (TMA) is an important fractured karstic reservoir in northern Morocco constituted by Liassic limestones and dolomites with a nearly sub-horizontal attitude, overlying basalts, shales and evaporates of Triassic age, as well as Paleozoic anchi-metamorphic schists. The zone is characterised by relative abundant rainfall (700 mm\\/y) and the absence of a surface watershed, which lead to an

Adriano Mayer; Mohammed Rouai; Ginette Saracco; Abdelilak Dekayir; Héléne Miche

2010-01-01

39

Compilation and R-matrix analysis of Big Bang nuclear reaction rates  

E-print Network

We use the R-matrix theory to fit low-energy data on nuclear reactions involved in Big Bang nucleosynthesis. A special attention is paid to the rate uncertainties which are evaluated on statistical grounds. We provide S factors and reaction rates in tabular and graphical formats.

Pierre Descouvemont; Abderrahim Adahchour; Carmen Angulo; Alain Coc; Elisabeth Vangioni-Flam

2004-07-06

40

Chapter 2: Tabular Data and Graphical Images in Support of the U.S. Geological Survey National Oil and Gas Assessment - The Wind River Basin Province  

USGS Publications Warehouse

This chapter describes data used in support of the process being applied by the U.S. Geological Survey (USGS) National Oil and Gas Assessment (NOGA) project. Digital tabular data used in this report and archival data that permit the user to perform further analyses are available elsewhere on this CD-ROM. Computers and software may import the data without transcription from the Portable Document Format files (.pdf files) of the text by the reader. Graphical images are provided as .pdf files and tabular data are provided in a raw form as tab-delimited text files (.tab files) because of the number and variety of platforms and software available.

Klett, T.R.; Le, P.A.

2007-01-01

41

Tabular Summary of the Third Follow-Up Questionnaire Data. Volume 1 [and] Volume 2 [and] Volume 3 [and] Volume 4. Sponsored Report Series NCES 79-228.  

ERIC Educational Resources Information Center

Tabular summaries of the 153 numerical responses to the Second Followup Questionnaire items of the National Longitudinal Study of the High School Class of 1972 are presented--20,872 individuals responded. These items summarize participants' educational experiences and occupational attainments from October 1973 to October 1974; continuing or…

Peng, Samuel S.; And Others

42

Google matrix 1 Google matrix  

E-print Network

Google matrix 1 Google matrix Fig.1. Google matrix of Wikipedia articles network, written [19]) A Google matrix is a particular stochastic matrix that is used by Google's PageRank algorithm be generated iteratively from the Google matrix using the power method. However, in order for the power method

Shepelyansky, Dima

43

Google matrix 1 Google matrix  

E-print Network

Google matrix 1 Google matrix A Google matrix is a particular stochastic matrix that is used by Google's PageRank algorithm. The matrix represents a graph with edges representing links between pages. The rank of each page can be generated iteratively from the Google matrix using the power method. However

Shepelyansky, Dima

44

supraHex: An R/Bioconductor package for tabular omics data analysis using a supra-hexagonal map?  

PubMed Central

Biologists are increasingly confronted with the challenge of quickly understanding genome-wide biological data, which usually involve a large number of genomic coordinates (e.g. genes) but a much smaller number of samples. To meet the need for data of this shape, we present an open-source package called ‘supraHex’ for training, analysing and visualising omics data. This package devises a supra-hexagonal map to self-organise the input data, offers scalable functionalities for post-analysing the map, and more importantly, allows for overlaying additional data for multilayer omics data comparisons. Via applying to DNA replication timing data of mouse embryogenesis, we demonstrate that supraHex is capable of simultaneously carrying out gene clustering and sample correlation, providing intuitive visualisation at each step of the analysis. By overlaying CpG and expression data onto the trained replication-timing map, we also show that supraHex is able to intuitively capture an inherent relationship between late replication, low CpG density promoters and low expression levels. As part of the Bioconductor project, supraHex makes accessible to a wide community in a simple way, what would otherwise be a complex framework for the ultrafast understanding of any tabular omics data, both scientifically and artistically. This package can run on Windows, Mac and Linux, and is freely available together with many tutorials on featuring real examples at http://supfam.org/supraHex. PMID:24309102

Fang, Hai; Gough, Julian

2014-01-01

45

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.

46

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

47

Graphical and tabular summaries of decay characteristics for once-through PWR, LMFBR, and FFTF fuel cycle materials. [Spent fuel, high-level waste fuel can scrap  

SciTech Connect

Based on the results of ORIGEN2 and a newly developed code called ORMANG, graphical and summary tabular characteristics of spent fuel, high-level waste, and fuel assembly structural material (cladding) waste are presented for a generic pressurized-water reactor (PWR), a liquid-metal fast breeder reactor (LMFBR), and the Fast Flux Test Facility (FFTF). The characteristics include radioactivity, thermal power, and toxicity (water dilution volume). Given are graphs and summary tables containing characteristic totals and the principal nuclide contributors as well as graphs comparing the three reactors for a single material and the three materials for a single reactor.

Croff, A.G.; Liberman, M.S.; Morrison, G.W.

1982-01-01

48

Modeling State-Space Aeroelastic Systems Using a Simple Matrix Polynomial Approach for the Unsteady Aerodynamics  

NASA Technical Reports Server (NTRS)

A simple matrix polynomial approach is introduced for approximating unsteady aerodynamics in the s-plane and ultimately, after combining matrix polynomial coefficients with matrices defining the structure, a matrix polynomial of the flutter equations of motion (EOM) is formed. A technique of recasting the matrix-polynomial form of the flutter EOM into a first order form is also presented that can be used to determine the eigenvalues near the origin and everywhere on the complex plane. An aeroservoelastic (ASE) EOM have been generalized to include the gust terms on the right-hand side. The reasons for developing the new matrix polynomial approach are also presented, which are the following: first, the "workhorse" methods such as the NASTRAN flutter analysis lack the capability to consistently find roots near the origin, along the real axis or accurately find roots farther away from the imaginary axis of the complex plane; and, second, the existing s-plane methods, such as the Roger s s-plane approximation method as implemented in ISAC, do not always give suitable fits of some tabular data of the unsteady aerodynamics. A method available in MATLAB is introduced that will accurately fit generalized aerodynamic force (GAF) coefficients in a tabular data form into the coefficients of a matrix polynomial form. The root-locus results from the NASTRAN pknl flutter analysis, the ISAC-Roger's s-plane method and the present matrix polynomial method are presented and compared for accuracy and for the number and locations of roots.

Pototzky, Anthony S.

2008-01-01

49

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

50

Radon constrains the transit time of springs water at the border between tabular Middle Atlas and the Sais Basin (Morocco)  

NASA Astrophysics Data System (ADS)

The tabular Middle Atlas (TMA) is an important fractured karstic reservoir in northern Morocco constituted by Liassic limestones and dolomites with a nearly sub-horizontal attitude, overlying basalts, shales and evaporates of Triassic age, as well as Paleozoic anchi-metamorphic schists. The zone is characterised by relative abundant rainfall (700 mm/y) and the absence of a surface watershed, which lead to an important groundwater reservoir hosted in the karstic (k-) aquifer. TMA is bordered to the North by extensive graben-like, normal, northward, fault-systems, which burden the Karstic formations under Plio-quaternary sediments at the Sais Basin border. At this limit, several important springs of high water-quality occur at the northernmost outcropping Lias limestone, which is overlaid in some areas by quaternary travertines. Two of these springs in particular, Bittit and Ribaa springs, provide almost drinking water for the town of Meknes (0.7 Million inhabitants), for local population and agriculture. These springs experienced a significant drop in water flow-rate in the last decades. Although the main origin of this water is certainly the k-aquifer, the drop in water-table raises several questions regarding the modality of water transport (influence of fractured and karstic systems in particular) and the possible participations of other groundwater reservoirs, which may deteriorate the high water-quality. A recent study has been carried out to shed some light on these questions, by using geochemical methods (K, Mg, Na, Ca, Fe, Mn, Ba, Sr, As, Sb, Hg, HCO3, SO4, NO3, Cl, Br, delta18-O, deltaD, Rn, EC, O2, pH, Eh, Temp). Constraints on the groundwater flow-path have been obtained by using a radon- hydrochemical- isotopic characterisation of spring waters. Here we report the results of the first geochemical sample collection (November 09). Several springs in the TMA yield Mg-Ca HCO3 rich water equilibrated with limestone and dolomite, having a very similar Rn activity of 3000 Bq/m3, unrelated to spring altitude. Similar radon activity is also found in a deep well in the Lias-confined aquifer of the Sais Basin and is hence considered to be the steady state activity in k-aquifer. Other springs situated at lower altitude yield more mineralised water (EC = 1200 uS/cm), richer in Na, K, Cl and Rn (15000 Bq/m3). These waters partially interacted with a non-karstic aquifer, most probably the deeper underlying Paleozoic schists (p-aquifer), as suggested by hydro chemical similarity with a water sample collected from a well in these shists. Since such water springs-out of Liassic carbonates, the measured Rn activity probably differs from the equilibrium activity achieved in the underlying p-aquifer, depending on the transit time from p-aquifer and the radon half-life (3.8 days). Furthermore, three other springs have hydrochemical characteristics intermediate between p- and k-aquifers, suggesting that a binary mixing of these waters occurred, either in the k- or in the p- aquifer. In principle, if the groundwater mixing occurred in k-aquifer, unsupported Rn activity would be lower than the activity expected from the binary mixing because of the time elapsed since the mixing occurred. The data show on the contrary that the mixed water has Rn activity higher than the expected activity calculated from the mixing. This suggests that groundwater mixing occurred in the p-aquifer. The excess of radon relatively to the expected activity calculated after the mixing, is interpreted to result from Rn radioactive ingrowth during the residence time in the p-aquifer, followed by radon decay occurred during uplift from p-aquifer to the spring in the Liassic carbonates. With this simple model, the measured Rn excess constraints the total time elapsed since the beginning of interaction with the p-aquifer on a time scale of 2 weeks. Remote sensed imaging of the area evidences that these "mixed" springs lies on important tectonic alignments, which suggest that fractures system could play a role in the fast upwelling of groundwater.

Mayer, Adriano; Rouai, Mohammed; Saracco, Ginette; Dekayir, Abdelilak; Miche, Héléne

2010-05-01

51

Matrix superpotentials  

NASA Astrophysics Data System (ADS)

We present a collection of matrix-valued shape invariant potentials which give rise to new exactly solvable problems of SUSY quantum mechanics. It includes all irreducible matrix superpotentials of the generic form W=kQ+\\frac{1}{k} R+P, where k is a variable parameter, Q is the unit matrix multiplied by a real-valued function of independent variable x, and P and R are the Hermitian matrices depending on x. In particular, we recover the Pron'ko-Stroganov 'matrix Coulomb potential' and all known scalar shape invariant potentials of SUSY quantum mechanics. In addition, five new shape invariant potentials are presented. Three of them admit a dual shape invariance, i.e. the related Hamiltonians can be factorized using two non-equivalent superpotentials. We find discrete spectrum and eigenvectors for the corresponding Schrödinger equations and prove that these eigenvectors are normalizable.

Nikitin, Anatoly G.; Karadzhov, Yuri

2011-07-01

52

Matrix Arithmetic  

NSDL National Science Digital Library

Using Mathcad, Maple, Mathmatica, or MatLab, learner should be able to experiment with matrix addition, subtraction, and (mostly) multiplication; to see that many familiar arithmetic properties of real numbers carry over to matrices.

David Smith

53

Matrix Algebra  

NSDL National Science Digital Library

An online course: learning units presented in worksheet format review the most important results, techniques and formulas in matrix algebra. Introduction to Matrices; Systems of Linear Equations; Determinant; Eigenvalues and Eigenvectors; and an Appendix of Mathematical Tables.

54

Chapter 3: Tabular Data and Graphical Images in Support of the U.S. Geological Survey National Oil and Gas Assessment - Western Gulf Province, Smackover-Austin-Eagle Ford Composite Total Petroleum System (504702)  

USGS Publications Warehouse

This chapter describes data used in support of the process being applied by the U.S. Geological Survey (USGS) National Oil and Gas Assessment (NOGA) project. Digital tabular data used in this report and archival data that permit the user to perform further analyses are available elsewhere on this CD-ROM. Computers and software may import the data without transcription from the Portable Document Format files (.pdf files) of the text by the reader. Because of the number and variety of platforms and software available, graphical images are provided as .pdf files and tabular data are provided in a raw form as tab-delimited text files (.tab files).

Klett, T.R.; Le, P.A.

2006-01-01

55

Tabular Summary of the Second Follow-Up Questionnaire Data 2 1/2 Years After High School. Volume 1 [and] Volume 2. Sponsored Reports Series. NCES 77-263 Reprint. Reprinted February 1979.  

ERIC Educational Resources Information Center

Tabular summaries of the 158 numerical responses to the Third Followup Questionnaire items of the National Longitudinal Study of the High School Class of 1972 are presented--20,092 individuals responded. These items summarize participants' educational experience and occupational attainments from October 1974 to October 1976; continuing or revised…

Peng, Samuel S.; Holt, Mary M.

56

The NOAA Tide Predictions application provides predictions in both graphical and tabular formats, with many user selected options, for over 3000 stations broken down by key areas in each state.  

E-print Network

The NOAA Tide Predictions application provides predictions in both graphical and tabular formats. Station Types: The NOAA Tide Predictions application provides predictions from 2 distinct categories by combining the harmonic constituents into a single tide curve. Subordinate - The high and low height values

57

Matrix Arithmetic  

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 addition, subtraction, and (mostly) multiplication; to see that many familiar arithmetic properties of real numbers carry over to matrices, but some do not. This is part of a larger collection of learning modules hosted by Duke University.

Blake, Lewis

58

Matrix trigonometry  

Microsoft Academic Search

This paper brings up to date with new results a matrix trigonometry which I originated about twenty-five years ago. In particular, a new view of the construction and nature of antieigenvectors implicit within a minmax theorem is presented, new results showing that both antieigenvectors and eigenvectors satisfy the nonlinear Euler equation are given, and new implications for a combinatorial higher

Karl Gustafson

1995-01-01

59

Monastic Matrix  

NSDL National Science Digital Library

One of the aims of the Monastic Matrix website is to disseminate research to both lay people and scholars about the "participation of Christian women in the religion and society of medieval Europe." This website allows visitors to view artwork, archaeology, stained glass, architecture, and textiles. By clicking on the link "Figurae" on the right hand side menu, visitors can browse these digital images by "title", "century", "community", and "image type". The "Beata Antonia", found by browsing "community", treats viewers to many beautiful 16th century Italian frescos. After visitors have had their fill of images, they might try the "Commentaria" section, which contains modern scholarly analyses. They should also take a look at the "Cartularium" which is a digital library of primary sources. Although many of the documents are in Latin, French, or other languages, some have been translated into English.

60

MatrixDB, the extracellular matrix interaction database: updated content, a new navigator and expanded functionalities  

PubMed Central

MatrixDB (http://matrixdb.ibcp.fr) is a freely available database focused on interactions established by extracellular proteins and polysaccharides. It is an active member of the International Molecular Exchange (IMEx) consortium and has adopted the PSI-MI standards for annotating and exchanging interaction data, either at the MIMIx or IMEx level. MatrixDB content has been updated by curation and by importing extracellular interaction data from other IMEx databases. Other major changes include the creation of a new website and the development of a novel graphical navigator, iNavigator, to build and expand interaction networks. Filters may be applied to build sub-networks based on a list of biomolecules, a specified interaction detection method and/or an expression level by tissue, developmental stage, and health state (UniGene data). Any molecule of the network may be selected and its partners added to the network at any time. Networks may be exported under Cytoscape and tabular formats and as images, and may be saved for subsequent re-use. PMID:25378329

Launay, G.; Salza, R.; Multedo, D.; Thierry-Mieg, N.; Ricard-Blum, S.

2015-01-01

61

Hybrid matrix fiber composites  

DOEpatents

Hybrid matrix fiber composites having enhanced compressive performance as well as enhanced stiffness, toughness and durability suitable for compression-critical applications. The methods for producing the fiber composites using matrix hybridization. The hybrid matrix fiber composites include two chemically or physically bonded matrix materials, whereas the first matrix materials are used to impregnate multi-filament fibers formed into ribbons and the second matrix material is placed around and between the fiber ribbons that are impregnated with the first matrix material and both matrix materials are cured and solidified.

Deteresa, Steven J.; Lyon, Richard E.; Groves, Scott E.

2003-07-15

62

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.

63

Carbonate fuel cell matrix  

DOEpatents

A carbonate fuel cell matrix comprising support particles and crack attenuator particles which are made platelet in shape to increase the resistance of the matrix to through cracking. Also disclosed is a matrix having porous crack attenuator particles and a matrix whose crack attenuator particles have a thermal coefficient of expansion which is significantly different from that of the support particles, and a method of making platelet-shaped crack attenuator particles.

Farooque, Mohammad (Huntington, CT); Yuh, Chao-Yi (New Milford, CT)

1996-01-01

64

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

65

Fire Model Matrix  

NSDL National Science Digital Library

The Fire Model Matrix is an on-line resource that presents four fire community models in a matrix that facilitates the exploration of the characteristics of each model. As part of the Advanced Fire Weather Forecasters Course, this matrix is meant to sensitize forecasters to the use of weather data in these fire models to forecast potential fire activity.

2014-09-14

66

Matrix with Prescribed Eigenvectors  

ERIC Educational Resources Information Center

It is a routine matter for undergraduates to find eigenvalues and eigenvectors of a given matrix. But the converse problem of finding a matrix with prescribed eigenvalues and eigenvectors is rarely discussed in elementary texts on linear algebra. This problem is related to the "spectral" decomposition of a matrix and has important technical…

Ahmad, Faiz

2011-01-01

67

Matrix cracking in ceramic-matrix composites  

Microsoft Academic Search

Matrix cracking in ceramic-matrix composites with unbonded frictional interface has been studied using fracture mechanics theory. The critical stress for extension of a fiber-bridged crack has been analyzed using the stress-intensity approach. The analysis uses a new shear-lag formulation of the crack-closure traction applied by the bridging fibers based on the assumption of a constant sliding friction stress over the

Sawai Danchaivijit; Dinesh K. Shetty

1993-01-01

68

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

69

Tabular data and graphical images in support of the U.S. Geological Survey National Oil and Gas Assessment--San Juan Basin Province (5022): Chapter 7 in Total petroleum systems and geologic assessment of undiscovered oil and gas resources in the San Juan Basin Province, exclusive of Paleozoic rocks, New Mexico and Colorado  

USGS Publications Warehouse

This chapter describes data used in support of the process being applied by the U.S. Geological Survey (USGS) National Oil and Gas Assessment (NOGA) project. Digital tabular data used in this report and archival data that permit the user to perform further analyses are available elsewhere on this CD–ROM. Computers and software may import the data without transcription from the Portable Document Format files (.pdf files) of the text by the reader. Because of the number and variety of platforms and software available, graphical images are provided as .pdf files and tabular data are provided in a raw form as tab-delimited text files (.tab files).

Klett, T.R.; Le, P.A.

2013-01-01

70

Chapter 6. Tabular data and graphical images in support of the U.S. Geological Survey National Oil and Gas Assessment-East Texas basin and Louisiana-Mississippi salt basins provinces, Jurassic Smackover interior salt basins total petroleum system (504902), Travis Peak and Hosston formations.  

USGS Publications Warehouse

This chapter describes data used in support of the process being applied by the U.S. Geological Survey (USGS) National Oil and Gas Assessment (NOGA) project. Digital tabular data used in this report and archival data that permit the user to perform further analyses are available elsewhere on the CD-ROM. Computers and software may import the data without transcription from the Portable Document Format files (.pdf files) of the text by the reader. Because of the number and variety of platforms and software available, graphical images are provided as .pdf files and tabular data are provided in a raw form as tab-delimited text files (.tab files).

U.S. Geological Survey

2006-01-01

71

Chapter 3. Tabular data and graphical images in support of the U.S. Geological Survey National Oil and Gas Assessment--East Texas basin and Louisiana-Mississippi salt basins provinces, Jurassic Smackover Interior salt basins total petroleum system (504902), Cotton Valley group.  

USGS Publications Warehouse

This chapter describes data used in support of the process being applied by the U.S. Geological Survey (USGS) National Oil and Gas Assessment (NOGA) project. Digital tabular data used in this report and archival data that permit the user to perform further analyses are available elsewhere on the CD-ROM. Computers and software may import the data without transcription from the Portable Document Format files (.pdf files) of the text by the reader. Because of the number and variety of platforms and software available, graphical images are provided as .pdf files and tabular data are provided in a raw form as tab-delimited text files (.tab files).

Klett, T.R.; Le, P.A.

2006-01-01

72

Automatic switching matrix  

DOEpatents

An automatic switching matrix that includes an apertured matrix board containing a matrix of wires that can be interconnected at each aperture. Each aperture has associated therewith a conductive pin which, when fully inserted into the associated aperture, effects electrical connection between the wires within that particular aperture. Means is provided for automatically inserting the pins in a determined pattern and for removing all the pins to permit other interconnecting patterns.

Schlecht, Martin F. (Cambridge, MA); Kassakian, John G. (Newton, MA); Caloggero, Anthony J. (Lynn, MA); Rhodes, Bruce (Dorchester, MA); Otten, David (Newton, MA); Rasmussen, Neil (Sudbury, MA)

1982-01-01

73

Transfer function matrix  

NASA Technical Reports Server (NTRS)

Given a multivariable system, it is proved that the numerator matrix N(s) of the transfer function evaluated at any system pole either has unity rank or is a null matrix. It is also shown that N(s) evaluated at any transmission zero of the system has rank deficiency. Examples are given for illustration.

Seraji, H.

1987-01-01

74

The Trigonometry of Matrix Statistics  

Microsoft Academic Search

A matrix trigonometry developed chiefly by this author during the past 40 years has interesting applications to certain situations in statistics. The key conceptual entity in this matrix trigonometry is the matrix (maximal) turning angle. Associated entities (originally so-named by this author) are the matrix antieigenvalues and corresponding antieigenvectors upon which the matrix obtains its critical turning angles. Because this

Karl Gustafson

2006-01-01

75

Novel graph distance matrix.  

PubMed

We have introduced novel distance matrix for graphs, which is based on interpretation of columns of the adjacency matrix of a graph as a set of points in n-dimensional space, n being the number of vertices in the graph. Numerical values for the distances are based on the Euclidean distance between n points in n-dimensional space. In this way, we have combined the traditional representation of graphs (drawn as 2D object of no fixed geometry) with their representation in n-dimensional space, defined by a set of n-points that lead to a representation of definite geometry. The novel distance matrix, referred to as natural distance matrix, shows some structural properties and offers novel graph invariants as molecular descriptors for structure-property-activity studies. One of the novel graph descriptors is the modified connectivity index in which the bond contribution for (m, n) bond-type is given by 1/ radical(m + n), where m and n are the valence of the end vertices of the bond. The novel distance matrix (ND) can be reduced to sparse distance-adjacency matrix (DA), which can be viewed as specially weighted adjacency matrix of a graph. The quotient of the leading eigenvalues of novel distance-adjacency matrix and novel distance matrix, as illustrated on a collection of graphs of chemical interest, show parallelism with a simple measure of graph density, based on the quotient of the number of edges in a graph and the maximal possible number of edges for graphs of the same size. PMID:20301095

Randi?, Milan; Pisanski, Tomaz; Novic, Marjana; Plavsi?, Dejan

2010-07-15

76

Hybrid matrix amplifier  

SciTech Connect

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

77

Hybrid matrix amplifier  

SciTech Connect

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

78

Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Basin Characteristics, 2002 Geospatial_Data_Presentation_Form: tabular digital data  

USGS Publications Warehouse

This tabular data set represents basin characteristics for the year 2002 compiled for every MRB_E2RF1 catchment of selected Major River Basins (MRBs, Crawford and others, 2006). These characteristics are reach catchment shape index, stream density, sinuosity, mean elevation, mean slope and number of road-stream crossings. The source data sets are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) RF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011) and the U.S. Census Bureau's TIGER/Line Files (U.S. Census Bureau,2006). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

Wieczorek, Michael E.; LaMotte, Andrew E.

2010-01-01

79

Pesticide-Exposure Matrix  

Cancer.gov

The "Pesticide-exposure Matrix" was developed to help epidemiologists and other researchers identify the active ingredients to which people were likely exposed when their homes and gardens were treated for pests in past years.

80

Matrix Multiplication with CUDA  

NSDL National Science Digital Library

This module teaches matrix multiplication in the context of enumerating paths in a graph and the basics of programming in CUDA. It emphasizes the power of using shared memory when programming on GPGPU architectures.

Rob Hochberg

81

Learning with matrix factorizations  

E-print Network

Matrices that can be factored into a product of two simpler matrices can serve as a useful and often natural model in the analysis of tabulated or high-dimensional data. Models based on matrix factorization (Factor Analysis, ...

Srebro, Nathan, 1974-

2004-01-01

82

Melanoma Histology Rules Matrix  

Cancer.gov

Cutaneous Melanoma Histology Coding Rules – Matrix C440-C449 (Excludes melanoma of all other sites) Rule Melanoma Specimen Histology Behavior Notes and Examples Code SINGLE MELANOMA OR MULTIPLE MELANOMAS ABSTRACTED AS A SINGLE PRIMARY H1 No

83

Kidney Histology Rules Matrix  

Cancer.gov

Kidney Histo Kidney Histology Coding Rules – Matrix C649 (Excludes lymphoma and leukemia M9590 – 9989 and Kaposi sarcoma M9140) Rule Pathology/Cytology Specimen Histology Behavior Notes and Examples Code SINGLE TUMOR H1 None or the pathology

84

Biomaterials Matrix Engineering  

E-print Network

Keywords Biomaterials Matrix Engineering Cell Adhesion Signaling Single Cell Tracking » Prof. Biomaterials 32 (2011), 7444. KurTh, i.; franKe, K.; PomPe, T.; Bornhäuser, m.; Werner, C. Hematopoietic stem

Schüler, Axel

85

ESS Matrix: Geology Majors  

NSDL National Science Digital Library

For the course development purposes, we can order and describe classes of system interactions possible using a design matrix that identifies case examples that illustrate the relationships and interactions between ...

86

The Inquiry Matrix  

NSDL National Science Digital Library

One way to advance inquiry in the classroom is to establish a systematic strategy for reflecting on our practice and our students' readiness to engage in increasingly complex scientific reasoning. The Matrix for Assessing and Planning Scientific Inquiry (

Julie Grady

2010-11-01

87

Low rank matrix completion  

E-print Network

We consider the problem of recovering a low rank matrix given a sampling of its entries. Such problems are of considerable interest in a diverse set of fields including control, system identification, statistics and signal ...

Nan, Feng, S.M. Massachusetts Institute of Technology

2009-01-01

88

New Solvable Matrix Integrals  

Microsoft Academic Search

We generalize Harish-Chandra-Itzykson-Zuber and certain other integrals\\u000a(Gross-Witten integral and integrals over complex matrices) using the notion of\\u000atau function of matrix argument. In this case one can reduce the matrix\\u000aintegral to the integral over eigenvalues, which in turn is certain tau\\u000afunction. We also consider a generalization of the Kontsevich integral.

A. Yu. Orlov

2002-01-01

89

An MCS Matrix  

NSDL National Science Digital Library

This module includes an interactive MCS Matrix of numerical simulations illustrating the physical processes controlling MCS evolution, as well as an archive of the entire Web module, Mesoscale Convective Systems: Squall Lines and Bow Echoes. Patterned after the CD Module A Convective Storm Matrix, the new MCS Matrix provides learners the opportunity for extensive exploration of the relationship between a MCSs environment and its structure. The matrix is composed of 21 four-dimensional numerical simulations based on the interactions of 10 different hodographs with a common thermodynamic profile. By comparing animated displays of these simulations learners are able to discern the influences of vertical wind shear and the Coriolis Force on MCS structure and evolution. A series of questions guides the exploration and helps to reveal key storm/environment relationships evident in the matrix. The subject matter expert for this module is Dr. Morris Weisman. Note: This module was originally published 5/28/99 as a CD-ROM (v1.0) as dual module along with a local copy of the Web module Mesoscale Convective Systems: Squall Lines and Bow Echoes (v3.0). The CD-ROM version of An MCS Matrix (1.0) works fairly well with Windows 98/ME/NT4/2000 but has reported to be problematic with Windows XP. Windows XP Users of version 1.0 should use the new, Web-based module.

2014-09-14

90

A Tabular Approach to Titration Calculations  

ERIC Educational Resources Information Center

Titrations are common laboratory exercises in high school and university chemistry courses, because they are easy, relatively inexpensive, and they illustrate a number of fundamental chemical principles. While students have little difficulty with calculations involving a single titration step, there is a significant leap in conceptual difficulty…

Lim, Kieran F.

2012-01-01

91

Matrix interdiction problem  

SciTech Connect

In the matrix interdiction problem, a real-valued matrix and an integer k is given. The objective is to remove k columns such that the sum over all rows of the maximum entry in each row is minimized. This combinatorial problem is closely related to bipartite network interdiction problem which can be applied to prioritize the border checkpoints in order to minimize the probability that an adversary can successfully cross the border. After introducing the matrix interdiction problem, we will prove the problem is NP-hard, and even NP-hard to approximate with an additive n{gamma} factor for a fixed constant {gamma}. We also present an algorithm for this problem that achieves a factor of (n-k) mUltiplicative approximation ratio.

Pan, Feng [Los Alamos National Laboratory; Kasiviswanathan, Shiva [Los Alamos National Laboratory

2010-01-01

92

Thermoelastic micromechanical stresses associated with a large alpha-silicon carbide grain in a polycrystalline beta-silicon carbide matrix  

NASA Technical Reports Server (NTRS)

The thermoelastic micromechanical stresses associated with a single large hexagonal alpha-SiC grain within a fine-grain-size cubic (3C) beta-SiC matrix were calculated. The naturally occurring residual stresses which are created during cooling from the processing temperatures and the effects of superimposed applied external stresses are both considered. A significant effect of the shape or geometry of the alpha-SiC grain is revealed, with the largest residual stresses associated with the naturally occurring tabular or platelet structure. The stresses are compared with the published strength results for these materials, which suggests that the residual stresses assume a significant role in the strength reduction that is observed.

Li, Zhuang; Bradt, Richard C.

1989-01-01

93

Matrix Big Brunch  

E-print Network

Following the holographic description of linear dilaton null Cosmologies with a Big Bang in terms of Matrix String Theory put forward by Craps, Sethi and Verlinde, we propose an extended background describing a Universe including both Big Bang and Big Crunch singularities. This belongs to a class of exact string backgrounds and is perturbative in the string coupling far away from the singularities, both of which can be resolved using Matrix String Theory. We provide a simple theory capable of describing the complete evolution of this closed Universe.

J. Bedford; C. Papageorgakis; D. Rodriguez-Gomez; J. Ward

2007-02-20

94

Complex matrix model duality  

SciTech Connect

The same complex matrix model calculates both tachyon scattering for the c=1 noncritical string at the self-dual radius and certain correlation functions of operators which preserve half the supersymmetry in N=4 super-Yang-Mills theory. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich-Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces.

Brown, T. W. [DESY, Hamburg, Theory Group, Notkestrasse, 85, D-22603 Hamburg (Germany)

2011-04-15

95

Review of Matrix Theory  

E-print Network

In this article we present a self contained review of the principles of Matrix Theory including the basics of light cone quantization, the formulation of 11 dimensional M-Theory in terms of supersymmetric quantum mechanics, the origin of membranes and the rules of compactification on 1,2 and 3 tori. We emphasize the unusual origins of space time and gravitation which are very different than in conventional approaches to quantum gravity. Finally we discuss application of Matrix Theory to the quantum mechanics of Schwarzschild black holes. This work is based on lectures given by the second author at the Cargese ASI 1997 and at the Institute for Advanced Study in Princeton.

Daniela Bigatti; Leonard Susskind

1997-12-06

96

Matrix lattice Boltzmann reloaded.  

PubMed

The lattice Boltzmann equation was introduced about 20 years ago as a new paradigm for computational fluid dynamics. In this paper, we revisit the main formulation of the lattice Boltzmann collision integral (matrix model) and introduce a new two-parametric family of collision operators, which permits us to combine enhanced stability and accuracy of matrix models with the outstanding simplicity of the most popular single-relaxation time schemes. The option of the revised lattice Boltzmann equation is demonstrated through numerical simulations of a three-dimensional lid-driven cavity. PMID:21536566

Karlin, Ilya; Asinari, Pietro; Succi, Sauro

2011-06-13

97

Lung Histology Rules Matrix  

Cancer.gov

Lung Histo Lung Histology Coding Rules – Matrix C340-C349 (Excludes lymphoma and leukemia M9590 – 9989 and Kaposi sarcoma M9140) Rule Pathology/Cytology Specimen Histology Behavior Notes and Examples Code SINGLE TUMOR H1 No pathology/cytology

98

THE MATRIX RECONSIDERED  

Microsoft Academic Search

This article employs the conceptual opposition of the red and blue pill that is presented in The Matrix trilogy as a mechanism for investigating the philosophical antagonisms and structural conflicts commonly associated with the ‘information society’. The text is divided into two main parts: The first reconsiders the logical structure of this pharmacological dialectic, arguing that the choice between these

David J. Gunkel

2008-01-01

99

Matrix Reference Manual  

NSDL National Science Digital Library

An alphabetical manual, from Abelian group to Zero matrix, that contains reference information about linear algebra and the properties of matrices, divided into the following sections: Properties; Eigenvalues; Special properties; Relations; Decompositions; Identities; Equations; Differentiation; Stochastic (statistical) properties; Signals; Examples; and Formal Algebra. The notation is based on the MATLAB software package.

Brookes, Mike

100

Matrix Analogies Test (MAT).  

ERIC Educational Resources Information Center

The Matrix Analogies Test measures nonverbal ability of handicapped and nonhandicapped children, ages 5-17, in a culture-fair fashion. It assesses pattern completion, reasoning by analogy, serial reasoning, and spatial visualization, with a short form available as a screening instrument. This paper describes the test's administration, format,…

Nicholson, Charles L.

1990-01-01

101

Review of Matrix Theory  

Microsoft Academic Search

In this article we present a self contained review of the principles of Matrix Theory including the basics of light cone quantization, the formulation of 11 dimensional M-Theory in terms of supersymmetric quantum mechanics, the origin of membranes and the rules of compactification on 1,2 and 3 tori. We emphasize the unusual origins of space time and gravitation which are

Daniela Bigatti; Leonard Susskind

1997-01-01

102

Oogenesis: matrix revolutions.  

PubMed

The mechanism of egg-chamber elongation during Drosophila oogenesis has always been mysterious. A new study shows that the egg chambers spin around their long axis laying down polarised extracellular matrix, which acts as a molecular corset to restrict radial expansion. PMID:21419992

Bastock, Rebecca; St Johnston, Daniel

2011-03-22

103

Biofilms: the matrix revisited  

Microsoft Academic Search

Microbes often construct and live within surface-associ- ated multicellular communities known as biofilms. The precise structure, chemistry and physiology of the biofilm all vary with the nature of its resident microbes and local environment. However, an important com- monality among biofilms is that their structural integrity critically depends upon an extracellular matrix produced by their constituent cells. Extracellular matrices might

Steven S. Branda; Åshild Vik; Lisa Friedman; Roberto Kolter

2005-01-01

104

Urinary Histology Rules Matrix  

Cancer.gov

Urinary Histo Renal Pelvis, Ureter, Bladder, and Other Urinary Histology Coding Rules Matrix C659, C669, C670-C679, C680-C689 (Excludes lymphoma and leukemia M9590-9989 and Kaposi sarcoma M9140) Rule Pathology/Cytology Specimen Histology Behavior Notes

105

Constructing the matrix  

NASA Astrophysics Data System (ADS)

As part of our 'toolkit' for analysing an extraterrestrial signal, the facility for calculating structural affinity to known phenomena must be part of our core capabilities. Without such a resource, we risk compromising our potential for detection and decipherment or at least causing significant delay in the process. To create such a repository for assessing structural affinity, all known systems (language parameters) need to be structurally analysed to 'place' their 'system' within a relational communication matrix. This will need to include all known variants of language structure, whether 'living' (in current use) or ancient; this must also include endeavours to incorporate yet undeciphered scripts and non-human communication, to provide as complete a picture as possible. In creating such a relational matrix, post-detection decipherment will be assisted by a structural 'map' that will have the potential for 'placing' an alien communication with its nearest known 'neighbour', to assist subsequent categorisation of basic parameters as a precursor to decipherment. 'Universal' attributes and behavioural characteristics of known communication structure will form a range of templates (Elliott, 2001 [1] and Elliott et al., 2002 [2]), to support and optimise our attempt at categorising and deciphering the content of an extraterrestrial signal. Detection of the hierarchical layers, which comprise intelligent, complex communication, will then form a matrix of calculations that will ultimately score affinity through a relational matrix of structural comparison. In this paper we develop the rationales and demonstrate functionality with initial test results.

Elliott, John

2012-09-01

106

Advanced Integration Matrix (AIM)  

NASA Technical Reports Server (NTRS)

This viewgraph presentation describes an Advanced Integration Matrix (AIM) to develop, test, and validate the integration of mission systems for long-duration manned space flight. The contents include: 1) Mission Needs Statement; 2) Scope; 3) General Objectives and Expectations; 4) Technical Approach; 5) AIM is an AHST Element; 6) Phase A and B Formulation Products; 7) Test Flow Plan; and 8) Benchmark Test.

Paul, Heather

2004-01-01

107

The Matrix of Linear Mappings  

E-print Network

On the set of mappings of the given set, we define the product of mappings. If A is associative algebra, then we consider the set of matrices, whose elements are linear mappings of algebra A. In algebra of matrices of linear mappings we define the operation of product. The operation is based on the product of mappings. If the matrix a of linear mappings has an inverse matrix, then the quasideterminant of the matrix a and the inverse matrix are matrices of linear mappings. In the paper, I consider conditions when a matrix of linear mappings has inverse matrix, as well methods of solving a system of linear equations in an associative algebra.

Aleks Kleyn

2010-01-27

108

The Reading Matrix  

NSDL National Science Digital Library

In the fall of 2000, a group of concerned educators came together to form The Reading Matrix, which was designed to create a place where both teachers and other interested persons could come together to find resources about reading and writing. Most of the resources are geared towards the language needs of ESL and international students, but given the cornucopia of materials here, there is really something for everyone. Scrolling down from the site’s homepage, visitors will come across areas that include a job database, the Reading Matrix Archives, interactive reading exercises, and a list of germane online journals. The Archives are a good place to start, as users will have the opportunity to look through subject-oriented resources for English-language learners that range from dictionaries, grammar quizzes, and speaking and listening practice.

109

National Employment Matrix  

NSDL National Science Digital Library

The US Bureau of Labor Statistics offers the National Industry-Occupation Employment Matrix. This fascinating searchable and browsable database allows users to track the employment distribution of an occupation among industries. Users can search or browse by industry or occupation. Results can be sorted by employment or projected (percent or numeric) change in employment. Data are available for over 500 occupations within 240 industries.

110

MATRIX MULTIPLY SCALAR FORMULATION  

E-print Network

MATRIX MULTIPLY ALGORITHMS SCALAR FORMULATION a(i, j) = b(i, k) * c(k, j) , i = 1 ­ ­ ­ n j = 1 AND j i k cobegin i : cobegin j : cobegin k : temp (i, j, k) := b(i, k) * c(k, j : cobegin j : temp (i, j) := 0 for k := 1 to n do temp (i, j) := temp (i, j) + b(i, k

Browne, James C.

111

Matrix string theory  

Microsoft Academic Search

Via compactification on a circle, the matrix mode] of M-theory proposed by Banks et a]. suggests a concrete identification between the large N limit of two-dimensional N = 8 supersymmetric Yang-Mills theory and type IIA string theory. In this paper we collect evidence that supports this identification. We explicitly identify the perturbative string states and their interactions, and describe the

Robbert Dijkgraaf; Erik Verlinde; Herman L Verlinde

1997-01-01

112

Metal Matrix Composites  

NASA Astrophysics Data System (ADS)

In metal matrix composites, a metal is combined with another, often nonmetallic, phase to produce a novel material having attractive engineering attributes of its own. A subject of much research in the 1980s and 1990s, this class of materials has, in the past decade, increased significantly in variety. Copper matrix composites, layered composites, high-conductivity composites, nanoscale composites, microcellular metals, and bio-derived composites have been added to a palette that, ten years ago, mostly comprised ceramic fiber- or particle-reinforced light metals together with some well-established engineering materials, such as WC-Co cermets. At the same time, research on composites such as particle-reinforced aluminum, aided by novel techniques such as large-cell 3-D finite element simulation or computed X-ray microtomography, has served as a potent vehicle for the elucidation of the mechanics of high-contrast two-phase elastoplastic materials, with implications that range well beyond metal matrix composites.

Mortensen, Andreas; Llorca, Javier

2010-08-01

113

Hypercube matrix computation task  

NASA Technical Reports Server (NTRS)

A major objective of the Hypercube Matrix Computation effort at the Jet Propulsion Laboratory (JPL) is to investigate the applicability of a parallel computing architecture to the solution of large-scale electromagnetic scattering problems. Three scattering analysis codes are being implemented and assessed on a JPL/California Institute of Technology (Caltech) Mark 3 Hypercube. The codes, which utilize different underlying algorithms, give a means of evaluating the general applicability of this parallel architecture. The three analysis codes being implemented are a frequency domain method of moments code, a time domain finite difference code, and a frequency domain finite elements code. These analysis capabilities are being integrated into an electromagnetics interactive analysis workstation which can serve as a design tool for the construction of antennas and other radiating or scattering structures. The first two years of work on the Hypercube Matrix Computation effort is summarized. It includes both new developments and results as well as work previously reported in the Hypercube Matrix Computation Task: Final Report for 1986 to 1987 (JPL Publication 87-18).

Calalo, Ruel H.; Imbriale, William A.; Jacobi, Nathan; Liewer, Paulett C.; Lockhart, Thomas G.; Lyzenga, Gregory A.; Lyons, James R.; Manshadi, Farzin; Patterson, Jean E.

1988-01-01

114

Distributive Property Matrix Multiplication (1)  

NSDL National Science Digital Library

This interactive Java learning tool allows a teacher to demonstrate and explore the distributive property with expressions in the factored form (a + b) (c + d) using a matrix multiplication method with students. Sliders determine the number values from 20 to -20 with increments of one-tenth. Check boxes show or hide the factored form, starting matrix values, matrix, products in the matrix, and solution.

Peter Tierney-Fife

2009-02-20

115

On the Matrix Exponential Function  

ERIC Educational Resources Information Center

A novel and simple formula for computing the matrix exponential function is presented. Specifically, it can be used to derive explicit formulas for the matrix exponential of a general matrix A satisfying p(A) = 0 for a polynomial p(s). It is ready for use in a classroom and suitable for both hand as well as symbolic computation.

Hou, Shui-Hung; Hou, Edwin; Pang, Wan-Kai

2006-01-01

116

The cellulose resource matrix.  

PubMed

The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where large scale competition can be expected and already is observed for the traditional industries such as the paper industry. Cellulose and lignocellulosic raw materials (like wood and non-wood fibre crops) are being utilised in many industrial sectors. Due to the initiated transition towards biobased economy, these raw materials are intensively investigated also for new applications such as 2nd generation biofuels and 'green' chemicals and materials production (Clark, 2007; Lange, 2007; Petrus & Noordermeer, 2006; Ragauskas et al., 2006; Regalbuto, 2009). As lignocellulosic raw materials are available in variable quantities and qualities, unnecessary competition can be avoided via the choice of suitable raw materials for a target application. For example, utilisation of cellulose as carbohydrate source for ethanol production (Kabir Kazi et al., 2010) avoids the discussed competition with easier digestible carbohydrates (sugars, starch) deprived from the food supply chain. Also for cellulose use as a biopolymer several different competing markets can be distinguished. It is clear that these applications and markets will be influenced by large volume shifts. The world will have to reckon with the increase of competition and feedstock shortage (land use/biodiversity) (van Dam, de Klerk-Engels, Struik, & Rabbinge, 2005). It is of interest - in the context of sustainable development of the bioeconomy - to categorize the already available and emerging lignocellulosic resources in a matrix structure. When composing such "cellulose resource matrix" attention should be given to the quality aspects as well as to the available quantities and practical possibilities of processing the feedstock and the performance in the end-application. The cellulose resource matrix should become a practical tool for stakeholders to make choices regarding raw materials, process or market. Although there is a vast amount of scientific and economic information available on cellulose and lignocellulosic resources, the accessibility for the interested layman or entrepreneur is very difficult and the relevance of the numerous details in the larger context is limited. Translation of science to practical accessible information with modern data management and data integration tools is a challenge. Therefore, a detailed matrix structure was composed in which the different elements or entries of the matrix were identified and a tentative rough set up was made. The inventory includes current commodities and new cellulose containing and raw materials as well as exotic sources and specialties. Important chemical and physical properties of the different raw materials were identified for the use in processes and products. When available, the market data such as price and availability were recorded. Established and innovative cellulose extraction and refining processes were reviewed. The demands on the raw material for suitable processing were collected. Processing parameters known to affect the cellulose properties were listed. Current and expected emerging markets were surveyed as well as their different demands on cellulose raw materials and processes. The setting up of the cellulose matrix as a practical tool requires two steps. Firstly, the reduction of the needed data by clustering of the characteristics of raw materials, processes and markets and secondly, the building of a database that can provide the answers to the questions from stakeholders with an indicative character. This paper describes the steps taken to achieve the defined clusters of most relevant and characteristic properties. These data can be expanded where required. More detailed specification can be obtained from the background literature and handbooks. Where gaps of information are ident

Keijsers, Edwin R P; Y?lmaz, Gülden; van Dam, Jan E G

2013-03-01

117

Commuting quantum matrix models  

NASA Astrophysics Data System (ADS)

We study a quantum system of p commuting matrices and find that such a quantum system requires an explicit curvature dependent potential in its Lagrangian for the system to have a finite energy ground state. In contrast it is possible to avoid such curvature dependence in the Hamiltonian. We study the eigenvalue distribution for such systems in the large matrix size limit. A critical rôle is played by p = 4. For p ? 4 the competition between eigenvalue repulsion and the attractive potential forces the eigenvalues to form a sharp spherical shell.

Filev, Veselin G.; O'Connor, Denjoe

2015-03-01

118

Marine Wave Model Matrix  

NSDL National Science Digital Library

The Marine Wave Model Matrix provides information on the formulation of wave models developed by the National Centers for Environmental Prediction (NCEP) and other modeling centers, including how these models forecast the generation, propagation, and dissipation of ocean waves using NWP model forecasts for winds and near-surface temperature and stability. Additionally, information is provided on data assimilation, post-processing of data, and verfication of wave models currently in operation. Within the post-processing pages are links to forecast output both in graphical and raw form, including links for data downloads. Links to COMET training on wave processes are also provided.

COMET

2006-05-16

119

Ceramic matrix and resin matrix composites: A comparison  

NASA Technical Reports Server (NTRS)

The underlying theory of continuous fiber reinforcement of ceramic matrix and resin matrix composites, their fabrication, microstructure, physical and mechanical properties are contrasted. The growing use of organometallic polymers as precursors to ceramic matrices is discussed as a means of providing low temperature processing capability without the fiber degradation encountered with more conventional ceramic processing techniques. Examples of ceramic matrix composites derived from particulate-filled, high char yield polymers and silsesquioxane precursors are provided.

Hurwitz, Frances I.

1987-01-01

120

Google matrix of Twitter  

NASA Astrophysics Data System (ADS)

We construct the Google matrix of the entire Twitter network, dated by July 2009, and analyze its spectrum and eigenstate properties including the PageRank and CheiRank vectors and 2DRanking of all nodes. Our studies show much stronger inter-connectivity between top PageRank nodes for the Twitter network compared to the networks of Wikipedia and British Universities studied previously. Our analysis allows to locate the top Twitter users which control the information flow on the network. We argue that this small fraction of the whole number of users, which can be viewed as the social network elite, plays the dominant role in the process of opinion formation on the network.

Frahm, K. M.; Shepelyansky, D. L.

2012-10-01

121

Light cone matrix product  

SciTech Connect

We show how to combine the light-cone and matrix product algorithms to simulate quantum systems far from equilibrium for long times. For the case of the XXZ spin chain at {Delta} = 0.5, we simulate to a time of {approx} 22.5. While part of the long simulation time is due to the use of the light-cone method, we also describe a modification of the infinite time-evolving bond decimation algorithm with improved numerical stability, and we describe how to incorporate symmetry into this algorithm. While statistical sampling error means that we are not yet able to make a definite statement, the behavior of the simulation at long times indicates the appearance of either 'revivals' in the order parameter as predicted by Hastings and Levitov (e-print arXiv:0806.4283) or of a distinct shoulder in the decay of the order parameter.

Hastings, Matthew B [Los Alamos National Laboratory

2009-01-01

122

Mixed Mode Matrix Multiplication  

SciTech Connect

In modern clustering environments where the memory hierarchy has many layers (distributed memory, shared memory layer, cache,...), an important question is how to fully utilize all available resources and identify the most dominant layer in certain computations. When combining algorithms on all layers together, what would be the best method to get the best performance out of all the resources we have? Mixed mode programming model that uses thread programming on the shared memory layer and message passing programming on the distributed memory layer is a method that many researchers are using to utilize the memory resources. In this paper, they take an algorithmic approach that uses matrix multiplication as a tool to show how cache algorithms affect the performance of both shared memory and distributed memory algorithms. They show that with good underlying cache algorithm, overall performance is stable. When underlying cache algorithm is bad, superlinear speedup may occur, and an increasing number of threads may also improve performance.

Meng-Shiou Wu; Srinivas Aluru; Ricky A. Kendall

2004-09-30

123

Hyaluronan: A Matrix Component  

NASA Astrophysics Data System (ADS)

The glucosaminoglycan hyaluronan is a key component of the extracellular matrix. It is a large, negatively charged molecule that can act as an ion exchange reservoir for positive ions. Hyaluronan is involved in renomedullary water handling through its water-binding capacity. In the renal medulla, the main source for hyaluronan production is the renomedullary interstitial cells. Hyaluronan synthases are found in the inner part of the plasma membrane and polymerize hyaluronan chains which are extruded into the extracellular space. Hyaluronidases are a family of enzymes involved in the degradation of hyaluronan. They have a wide range of properties, including differences in size, inhibitor sensitivities, catalytic mechanisms, substrate specificities and pH optima.

Rügheimer, Louise

2008-09-01

124

HeterogeneousMatrix-MatrixMultiplication or Partitioninga Square into Rectangles  

E-print Network

HeterogeneousMatrix-MatrixMultiplication or Partitioninga Square into Rectangles: NP square irito p rectangles ofgiven area SI,sa, .. . sp (such that E:='=,s, = l),so as to mini- mize (i:='=,2 6 M 4.36 (obtained when all rectangles are squares, which is not achievable in this example either

Beaumont, Olivier

125

Matrix cracking and debonding of ceramic-matrix composites  

Microsoft Academic Search

The effects of matrix cracking and debonding which occur in ceramic-matrix composites are described by a micromechanical model. The cracking and debonding processes induce loss of stiffness, inelastic strains, hysteresis loops and crack closure. These features are analysed within the framework of Continuum Mechanics by the introduction of internal variables identified in the micromechanical analysis. The evolution laws of the

Frederick A. Leckie

1996-01-01

126

How to Study a Matrix  

ERIC Educational Resources Information Center

This study investigated how best to study a matrix. Fifty-three participants studied a matrix topically (1 column at a time), categorically (1 row at a time), or in a unified way (all at once). Results revealed that categorical and unified study produced higher: (a) performance on relationship and fact tests, (b) study material satisfaction, and…

Jairam, Dharmananda; Kiewra, Kenneth A.; Kauffman, Douglas F.; Zhao, Ruomeng

2012-01-01

127

Synthetic Division and Matrix Factorization  

ERIC Educational Resources Information Center

Synthetic division is viewed as a change of basis for polynomials written under the Newton form. Then, the transition matrices obtained from a sequence of changes of basis are used to factorize the inverse of a bidiagonal matrix or a block bidiagonal matrix.

Barabe, Samuel; Dubeau, Franc

2007-01-01

128

Markowitz Portfolio Optimization with Matrix  

E-print Network

Markowitz Portfolio Optimization with Matrix Algebra MATH ­ 547 ­ 003 Linear Algebra with Applications Brent A. Kolb #12;Markowitz Portfolio Optimization with Matrix Algebra Abstract The objective of this paper is to apply linear algebra to case scenarios of Markowitz Portfolio Optimization. The goal

Marzuola, Jeremy

129

Fatigue of ceramic matrix composites  

Microsoft Academic Search

Fatigue in ceramic matrix composites typically occurs when matrix cracks are present. It proceeds by cyclic degradation of the sliding resistance of the interface. The basic mechanisms are discussed and a methodology is developed that enables fatigue life predictions to be made, based on a minimum number of experimental measurements. The methodology relies on analysis of hysteresis loops. Changes in

A. G. Evans; F. W. Zok; R. M. McMeeking

1995-01-01

130

Noncommutative geometry and Matrix theory  

Microsoft Academic Search

We study toroidal compactification of Matrix theory, using ideas and results of non-commutative geometry. We generalize this to compactification on the noncommutative torus, explain the classification of these backgrounds, and argue that they correspond in supergravity to tori with constant background three-form tensor field. The paper includes an introduction for mathematicians to the IKKT formulation of Matrix theory and its

Alain Connes; Michael R. Douglas; Albert Schwarz

1998-01-01

131

Hybridized polymer matrix composites  

NASA Technical Reports Server (NTRS)

The extent to which graphite fibers are released from resin matrix composites that are exposed to fire and impact conditions was determined. Laboratory simulations of those conditions that could exist in the event of an aircraft crash and burn situation were evaluated. The effectiveness of various hybridizing concepts in preventing this release of graphite fibers were also evaluated. The baseline (i.e., unhybridized) laminates examined were prepared from commercially available graphite/epoxy, graphite/polyimide, and graphite/phenolic materials. Hybridizing concepts investigated included resin fillers, laminate coatings, resin blending, and mechanical interlocking of the graphite reinforcement. The baseline and hybridized laminates' mechanical properties, before and after isothermal and humidity aging, were also compared. It was found that a small amount of graphite fiber was released from the graphite/epoxy laminates during the burn and impact conditions used in this program. However, the extent to which the fibers were released is not considered a severe enough problem to preclude the use of graphite reinforced composites in civil aircraft structure. It also was found that several hybrid concepts eliminated this fiber release. Isothermal and humidity aging did not appear to alter the fiber release tendencies.

House, E. E.; Hoggatt, J. T.; Symonds, W. A.

1980-01-01

132

Matrix Representation of Special Relativity  

E-print Network

I compare the matrix representation of the basic statements of Special Relativity with the conventional vector space representation. It is shown, that the matrix form reproduces all equations in a very concise and elegant form, namely: Maxwell equations, Lorentz-force, energy-momentum tensor, Dirac-equation and Lagrangians. The main thesis is, however, that both forms are nevertheless not equivalent, but matrix representation is superior and gives a deeper insight into physical reality, because it is based on much less assumptions. It allows a better understanding of Minkowski spacetime on the basis of matrix algebra. An escpecially remarkable result of the consequent usage of this alge- braic concept is the formulation of Diracs equation in a novel matrix form. This equation can be generalized to include a new variant of Yang-Mills gauge fields, which possibly express unified electro-weak interactions in a new way.

Wolfgang Koehler

2007-03-08

133

Micromechanics for ceramic matrix composites  

NASA Technical Reports Server (NTRS)

The fiber substructuring concepts and the micromechanics equations that are embedded in the Ceramic Matrix Composite Analyzer (CEMCAN) computer code are described as well as the code itself, its current features and capabilities, and some examples to demonstrate the code's versatility. The methodology is equally applicable to metal matrix and polymer matrix composites. The prediction of ply mechanical and thermal properties agree very well with the existing models in the Integrated Composite Analyzer and the Ceramic Matrix Composite Analyzer, lending credence to the fiber substructuring approach. Fiber substructuring can capture greater local detail than conventional unit-cell-based micromechanical theories. It offers promise in simulating complex aspects of micromechanics in ceramic matrix composites.

Murthy, P. L. N.; Chamis, C. C.

1991-01-01

134

Sparse Matrix Computational Techniques in Concept Decomposition Matrix Approximation  

NASA Astrophysics Data System (ADS)

Recently the concept decomposition based on document clustering strate gies has drawn researchers' attention. These decompositions are obtained by taking the least-squares approximation onto the linear subspace spanned by all the con cept vectors. In this chapter, a new class of numerical matrix computation methods has been developed in computing the approximate decomposition matrix in concept decomposition technique. These methods utilize the knowledge of matrix sparsity pattern techniques in preconditioning field. An important advantage of these ap proaches is that they are computationally more efficient, fast in computing the rank ing vector and require much less memory than the least—squares based approach while maintaining retrieval accuracy.

Shen, Chi; Williams, Duran

135

M-theoretic matrix models  

E-print Network

Some matrix models admit, on top of the usual 't Hooft expansion, an M-theory-like expansion, i.e. an expansion at large N but where the rest of the parameters are fixed, instead of scaling with N. These models, which we call M-theoretic matrix models, appear in the localization of Chern-Simons-matter theories, and also in two-dimensional statistical physics. Generically, their partition function receives non-perturbative corrections which are not captured by the 't Hooft expansion. In this paper, we discuss general aspects of these type of matrix integrals and we analyze in detail two different examples. The first one is the matrix model computing the partition function of N=4 supersymmetric Yang-Mills theory in three dimensions with one adjoint hypermultiplet and N_f fundamentals, which has a conjectured M-theory dual, and which we call the N_f matrix model. The second one, which we call the polymer matrix model, computes form factors of the 2d Ising model and is related to the physics of 2d polymers. In both cases we determine their exact planar limit. In the N_f matrix model, the planar free energy reproduces the expected behavior of the M-theory dual. We also study their M-theory expansion by using Fermi gas techniques, and we find non-perturbative corrections to the 't Hooft expansion.

Alba Grassi; Marcos Marino

2014-11-30

136

M-theoretic matrix models  

NASA Astrophysics Data System (ADS)

Some matrix models admit, on top of the usual 't Hooft expansion, an M-theory-like expansion, i.e. an expansion at large N but where the rest of the parameters are fixed, instead of scaling with N . These models, which we call M-theoretic matrix models, appear in the localization of Chern-Simons-matter theories, and also in two-dimensional statistical physics. Generically, their partition function receives non-perturbative corrections which are not captured by the 't Hooft expansion. In this paper, we discuss general aspects of these type of matrix integrals and we analyze in detail two different examples. The first one is the matrix model computing the partition function of supersymmetric Yang-Mills theory in three dimensions with one adjoint hypermultiplet and N f fundamentals, which has a conjectured M-theory dual, and which we call the N f matrix model. The second one, which we call the polymer matrix model, computes form factors of the 2d Ising model and is related to the physics of 2d polymers. In both cases we determine their exact planar limit. In the N f matrix model, the planar free energy reproduces the expected behavior of the M-theory dual. We also study their M-theory expansion by using Fermi gas techniques, and we find non-perturbative corrections to the 't Hooft expansion.

Grassi, Alba; Mariño, Marcos

2015-02-01

137

A data locality methodology for matrix–matrix multiplication algorithm  

Microsoft Academic Search

Matrix-Matrix Multiplication (MMM) is a highly important kernel in linear algebra algorithms and the performance of its implementations\\u000a depends on the memory utilization and data locality. There are MMM algorithms, such as standard, Strassen–Winograd variant,\\u000a and many recursive array layouts, such as Z-Morton or U-Morton. However, their data locality is lower than that of the proposed\\u000a methodology. Moreover, several SOA

Nicolaos Alachiotis; Vasileios I. Kelefouras; George S. Athanasiou; Harris E. Michail; Angeliki S. Kritikakou; Costas E. Goutis

138

Canonical density matrix perturbation theory  

E-print Network

Density matrix perturbation theory [Niklasson and Challacombe, Phys. Rev. Lett. 92, 193001 (2004)] is generalized to canonical (NVT) free energy ensembles in tight-binding, Hartree-Fock or Kohn-Sham density functional theory. The canonical density matrix perturbation theory can be used to calculate temperature dependent response properties from the coupled perturbed self-consistent field equations as in density functional perturbation theory. The method is well suited to take advantage of sparse matrix algebra to achieve linear scaling complexity in the computational cost as a function of system size for sufficiently large non-metallic materials and metals at high temperatures.

Niklasson, Anders M N; Rubensson, Emanuel H; Rudberg, Elias

2015-01-01

139

Matrix models for 2* theories  

SciTech Connect

We show how to represent a class of expressions involving discrete sums over partitions as matrix models. We apply this technique to the partition functions of 2* theories, i.e. Seiberg-Witten theories with the massive hypermultiplet in the adjoint representation. We consider theories in four, five, and six dimensions, and obtain new matrix models, respectively, of rational, trigonometric, and elliptic type. The matrix models for five- and six-dimensional U(1) theories are derived from the topological vertex construction related to curves of genus one and two.

Sulkowski, Piotr [Physikalisches Institut der Universitaet Bonn and Bethe Center for Theoretical Physics, Nussallee 12, 53115 Bonn (Germany) and Soltan Institute for Nuclear Studies, Hoza 69, 00-681 Warsaw (Poland)

2009-10-15

140

Genotype imputation via matrix completion  

PubMed Central

Most current genotype imputation methods are model-based and computationally intensive, taking days to impute one chromosome pair on 1000 people. We describe an efficient genotype imputation method based on matrix completion. Our matrix completion method is implemented in MATLAB and tested on real data from HapMap 3, simulated pedigree data, and simulated low-coverage sequencing data derived from the 1000 Genomes Project. Compared with leading imputation programs, the matrix completion algorithm embodied in our program MENDEL-IMPUTE achieves comparable imputation accuracy while reducing run times significantly. Implementation in a lower-level language such as Fortran or C is apt to further improve computational efficiency. PMID:23233546

Chi, Eric C.; Zhou, Hua; Chen, Gary K.; Del Vecchyo, Diego Ortega; Lange, Kenneth

2013-01-01

141

Stochastic determination of matrix determinants  

E-print Network

Matrix determinants play an important role in data analysis, in particular when Gaussian processes are involved. Due to currently exploding data volumes linear operations - matrices - acting on the data are often not accessible directly, but are only represented indirectly in form of a computer routine. Such a routine implements the transformation a data vector undergoes under matrix multiplication. Meanwhile efficient probing routines to estimate a matrix's diagonal or trace, based solely on such computationally affordable matrix-vector multiplications, are well known and frequently used in signal inference, a stochastic estimate for its determinant is still lacking. In this work a probing method for the logarithm of a determinant of a linear operator is introduced. This method rests upon a reformulation of the log-determinant by an integral representation and the transformation of the involved terms into stochastic expressions. This stochastic determinant determination enables large-size applications in Bay...

Dorn, Sebastian

2015-01-01

142

Welcome to PRI's "Matrix Project"!  

NSDL National Science Digital Library

The "Matrix Project" is an activity for students in which they receive bags of 11,000-year-old excavated materials including fossils, rocks, preserved organic material, etc.; students then identify the materials and learn more about them.

2001-04-03

143

Lung Multiple Primary Rules Matrix  

Cancer.gov

Lung Multiple Primary Rules – Matrix C340-C349 (Excludes lymphoma and leukemia M9590 – 9989 and Kaposi sarcoma M9140) * Prepare one abstract. Use the histology coding rules to assign the appropriate histology code. ** Prepare two or more abstracts.

144

Performance Appraisal for Matrix Management.  

ERIC Educational Resources Information Center

A matrix management system designed for use by a highly technical nuclear weapons research and development facility to improve productivity and flexibility by the use of multiple authority, responsibility, and accountability relationships is described. (MSE)

Edwards, M. R.; Sproull, J. Ruth

1985-01-01

145

Leslie Matrix I Formal Demography  

E-print Network

I 8 #12;The Leslie matrix is a special case of a projection matrix for an age-classified population-Classes The population is now described by the following model: n1(t + 1) = f1n1(t) + f2n2(t) (1) n2(t+1) = p1n1 (2) n1 to answer: Is there a unique exponential growth rate for such a population analogous to the unstructured

146

Molybdenum disilicide alloy matrix composite  

DOEpatents

Compositions of matter consisting of matrix materials having silicon carbide dispersed throughout them and methods of making the compositions are disclosed. A matrix material is an alloy of an intermetallic compound, molybdenum disilicide, and at least one secondary component which is a refractory silicide. The silicon carbide dispersant may be in the form of VLS whiskers, VS whiskers, or submicron powder or a mixture of these forms. 3 figures.

Petrovic, J.J.; Honnell, R.E.; Gibbs, W.S.

1991-12-03

147

Matrix Tree Theorems Nikhil Srivastava  

E-print Network

vertices. Then en-1(L) = n. Proof. Orient the edges of T arbitrarily. Let L = BT B where B is the edge-vertex incidence matrix and use Lemma 3 to obtain en-1(L) = en-1(BT B) = xV en-1(BT ·,¯xB·,¯x) We will show in matrix notation, we have y - x = BT zy which upon ignoring the row indexed by x becomes y = BT ·,¯xzy

Spielman, Daniel A.

148

Molybdenum disilicide alloy matrix composite  

DOEpatents

Compositions of matter consisting of matrix materials having silicon carbide dispersed throughout them and methods of making the compositions. A matrix material is an alloy of an intermetallic compound, molybdenum disilicide, and at least one secondary component which is a refractory silicide. The silicon carbide dispersant may be in the form of VLS whiskers, VS whiskers, or submicron powder or a mixture of these forms.

Petrovic, John J. (Los Alamos, NM); Honnell, Richard E. (Los Alamos, NM); Gibbs, W. Scott (Los Alamos, NM)

1991-01-01

149

Molybdenum disilicide alloy matrix composite  

DOEpatents

Compositions of matter consisting of matrix matrials having silicon carbide dispersed throughout them and methods of making the compositions. A matrix material is an alloy of an intermetallic compound, molybdenum disilicide, and at least one secondary component which is a refractory silicide. The silicon carbide dispersant may be in the form of VLS whiskers, VS whiskers, or submicron powder or a mixture of these forms.

Petrovic, John J. (Los Alamos, NM); Honnell, Richard E. (Los Alamos, NM); Gibbs, W. Scott (Los Alamos, NM)

1990-01-01

150

Oriented matrix promotes directional tubulogenesis.  

PubMed

Detailed control over the structural organization of scaffolds and engineered tissue constructs is a critical need in the quest to engineer functional tissues using biomaterials. This work presents a new approach to spatially direct endothelial tubulogenesis. Micropatterned fibronectin substrates were used to control lung fibroblast adhesion and growth and the subsequent deposition of fibroblast-derived matrix during culture. The fibroblast-derived matrix produced on the micropatterned substrates was tightly oriented by these patterns, with an average variation of only 8.5°. Further, regions of this oriented extracellular matrix provided directional control of developing endothelial tubes to within 10° of the original micropatterned substrate design. Endothelial cells seeded directly onto the micropatterned substrate did not form tubes. A metric for matrix anisotropy showed a relationship between the fibroblast-derived matrix and the endothelial tubes that were subsequently developed on the same micropatterns with a resulting aspect ratio over 1.5 for endothelial tubulogenesis. Micropatterns in "L" and "Y" shapes were used to direct endothelial tubes to turn and branch with the same level of precision. These data demonstrate that anisotropic fibroblast-derived matrices instruct the alignment and shape of endothelial tube networks, thereby introducing an approach that could be adapted for future design of microvascular implants featuring organ-specific natural matrix that patterns microvascular growth. PMID:25219769

Soucy, Patricia A; Hoh, Maria; Heinz, Will; Hoh, Jan; Romer, Lewis

2015-01-01

151

Octonionic matrix representation and electromagnetism  

NASA Astrophysics Data System (ADS)

Keeping in mind the important role of octonion algebra, we have obtained the electromagnetic field equations of dyons with an octonionic 8×8 matrix representation. In this paper, we consider the eight — dimensional octonionic space as a combination of two (external and internal) four-dimensional spaces for the existence of magnetic monopoles (dyons) in a higher-dimensional formalism. As such, we describe the octonion wave equations in terms of eight components from the 8 × 8 matrix representation. The octonion forms of the generalized potential, fields and current source of dyons in terms of 8 × 8 matrix are discussed in a consistent manner. Thus, we have obtained the generalized Dirac-Maxwell equations of dyons from an 8×8 matrix representation of the octonion wave equations in a compact and consistent manner. The generalized Dirac-Maxwell equations are fully symmetric Maxwell equations and allow for the possibility of magnetic charges and currents, analogous to electric charges and currents. Accordingly, we have obtained the octonionic Dirac wave equations in an external field from the matrix representation of the octonion-valued potentials of dyons.

Chanyal, B. C.

2014-12-01

152

Rank-Sparsity Incoherence for Matrix Decomposition  

E-print Network

Suppose we are given a matrix that is formed by adding an unknown sparse matrix to an unknown low-rank matrix. Our goal is to decompose the given matrix into its sparse and low-rank components. Such a problem arises in a ...

Chandrasekaran, Venkat

153

Shrinkage estimation of the realized relationship matrix  

Technology Transfer Automated Retrieval System (TEKTRAN)

The additive relationship matrix plays an important role in mixed model prediction of breeding values. For genotype matrix X (loci in columns), the product XX' is widely used as a realized relationship matrix, but the scaling of this matrix is ambiguous. Our first objective was to derive a proper ...

154

Propagation of Errors for Matrix Inversion  

E-print Network

A formula is given for the propagation of errors during matrix inversion. An explicit calculation for a 2 by 2 matrix using both the formula and a Monte Carlo calculation are compared. A prescription is given to determine when a matrix with uncertain elements is sufficiently nonsingular for the calculation of the covariances of the inverted matrix elements to be reliable.

M. Lefebvre; R. K. Keeler; R. Sobie; J. White

1999-09-17

155

Progress in matrix metalloproteinase research  

PubMed Central

Matrix metalloproteinases (MMPs) are now acknowledged as key players in the regulation of both cell–cell and cell–extracellular matrix interactions. They are involved in modifying matrix structure, growth factor availability and the function of cell surface signalling systems, with consequent effects on cellular differentiation, proliferation and apoptosis. They play central roles in morphogenesis, wound healing, tissue repair and remodelling in response to injury and in the progression of diseases such as arthritis, cancer and cardiovascular disease. Because of their wide spectrum of activities and expression sites, the elucidation of their potential as drug targets in disease or as important features of the repair process will be dependent upon careful analysis of their role in different cellular locations and at different disease stages. Novel approaches to the specific regulation of individual MMPs in different contexts are also being developed. PMID:18619669

Murphy, Gillian; Nagase, Hideaki

2010-01-01

156

Spectral decomposition of a matrix using the generalized sign matrix  

NASA Technical Reports Server (NTRS)

An algorithm for spectral decomposition is presented which does not require knowledge of eigenvalues and eigenvectors. A set of eigenprojectors are defined which covers the entire spectrum of a matrix, and special attention is given to the projection on the zero eigenvalue. Some useful applications are discussed in the paper.

Denman, E. D.; Leyva-Ramos, J.

1981-01-01

157

Matrix management for aerospace 2000  

NASA Technical Reports Server (NTRS)

The matrix management approach to program management is described, showing that it is an organized approach to attaining program objectives by defining and structuring all elements so as to form a single system whose parts are united by interaction. The objective of the systems approach is to attain an uncompromised complete coverage of the program management effort. It is demonstrated that beginning with an analysis of the functions necessary to carry out a given program, a model must be defined; a matrix of responsibility assignment must be prepared; and each operational process is examined to establish how it is to be implemented and how it relates to all other processes.

Mccarthy, J. F., Jr.

1980-01-01

158

Switching Matrix For Optical Signals  

NASA Technical Reports Server (NTRS)

Proposed matrix of electronically controlled shutters switches signals in optical fibers between multiple input and output channels. Size, weight, and power consumption reduced. Device serves as building block for small, low-power, broad-band television- and data-signal-switching systems providing high isolation between nominally disconnected channels.

Grove, Charles H.

1990-01-01

159

The Enrollment Analysis Matrix Concept.  

ERIC Educational Resources Information Center

The underlying assumptions and the structure of the enrollment analysis matrix (EAM) concept are discussed. EAM is a component of the Strategic Planning Project of the National Center for Higher Education Management Systems. EAM relates changes in the population of potential students external to the institution to the impacts that might result…

Chisholm, Mark

160

Responsbility Matrix Data, Communications, Security  

E-print Network

Responsbility Matrix Data, Communications, Security New Construction only SYSTEM SUPPLY INSTALL, Communications, Security New Construction only SYSTEM SUPPLY INSTALL TERMINATE TEST Cost Est. Backbone (Copper above See data system above Network Video Recorder Dal CS Dal AC n/a n/a Dal CS&AC Cameras Elect Elect

Brownstone, Rob

161

Benign Brain Histology Rules matrix  

Cancer.gov

Benign and Borderline Intracranial and CNS Tumors Histology Coding Rules – Matrix C700, C701, C709, C710-C719, C720-C725, C728, C729, C751-C753 Note: Malignant intracranial and CNS tumors have a separate set of rules. Rule Pathology/Cytology Specimen

162

Matrix converters: a technology review  

Microsoft Academic Search

The matrix converter is an array of controlled semiconductor switches that connects directly the three-phase source to the three-phase load. This converter has several attractive features that have been investigated in the last two decades. In the last few years, an increase in research work has been observed, bringing this topology closer to the industrial application. This paper presents the

Patrick W. Wheeler; José Rodríguez; Jon C. Clare; Lee Empringham; Alejandro Weinstein

2002-01-01

163

Curing of Epoxy Matrix Composites  

Microsoft Academic Search

Models were developed which describe the curing process of composites constructed from continuous fiber-reinforced, thermosetting resin matrix prepreg materials. On the basis of the models, a computer code was developed, which for flat-plate composites cured by a specified cure cycle, provides the temperature distribution, the degree of cure of the resin, the resin viscosity inside the composite, the void sizes,

Alfred C. Loos; George S. Springer

1983-01-01

164

Integrability and generalized monodromy matrix  

SciTech Connect

We construct the generalized monodromy matrix M-circumflex({omega}) of two-dimensional string effective action by introducing the T-duality group properties. The integrability conditions with general solutions depending on spectral parameter are given. This construction is investigated for the exactly solvable Wess, Zumino, Novikov, and Witten model in pp-wave limit when B=0.

Lhallabi, T.; Moujib, A. [Lab/UFR--Physique des Hautes Energies, Faculte des Sciences, Rabat (Morocco); Groupement National de Physique des Hautes Energies, Siege focal, Faculte des Sciences de Rabat, Rabat (Morocco); Virtual African Centre for Basic Science and Technology, Focal point, LabUFR-PHE, Rabat (Morocco)

2007-09-15

165

Matrix metalloproteinases in arthritic disease  

Microsoft Academic Search

CHAPTER SUMMARY: The role of matrix metalloproteinases in the degradative events invoked in the cartilage and bone of arthritic joints has long been appreciated and attempts at the development of proteinase inhibitors as potential therapeutic agents have been made. However, the spectrum of these enzymes orchestrating connective tissue turnover and general biology is much larger than anticipated. Biochemical studies of

Gillian Murphy; Vera Knäuper; Susan Atkinson; George Butler; William English; Mike Hutton; Jan Stracke; Ian Clark

2002-01-01

166

The spinorial R-matrix  

NASA Astrophysics Data System (ADS)

The R-matrix acting in the tensor product of two spinor representation spaces of Lie algebra so(d) is considered thoroughly. The corresponding Yang-Baxter relation is proved and the underlying local Yang-Baxter equation is established.

Chicherin, D.; Derkachov, S.; Isaev, A. P.

2013-12-01

167

Polymer derived ceramic matrix composites  

Microsoft Academic Search

Preceramic polymers offer a unique method to fabricate ceramic matrix composites (CMC). Relatively large and complex shapes were fabricated using a polysilazane polymer and silicon carbide based reinforcements of CG Nicalon™ and HI-nicalon™ fibers. This paper summarizes a raw material system and the fabrication process used to prepare two-dimensional cloth reinforced composites. Typical tensile, shear and compressive properties of CMCs

R. Jones; A. Szweda; D. Petrak

1999-01-01

168

Perturbation semigroup of matrix algebras  

E-print Network

In this article we analyze the structure of the semigroup of inner perturbations in noncommutative geometry. This perturbation semigroup is associated to a unital associative *-algebra and extends the group of unitary elements of this *-algebra. We compute the perturbation semigroup for all matrix algebras.

Niels Neumann; Walter D. van Suijlekom

2014-10-22

169

Matrix Management of Continuing Education  

ERIC Educational Resources Information Center

Responding to the problem of an appropriate institutional structure to meet the needs of a clientele group dominated by the part-time student, the author promotes matrix management, which calls for great dexterity, flexibility, and willingness to relinquish power while recognizing the need for coordination, collaboration, and continuation. (EA)

Loring, Rosalind K.

1976-01-01

170

STRATIFICATION OF MATRIX PENCILS IN  

E-print Network

. Erik Elmroth, Pedher Johansson, Stefan Johansson, and Bo K°agstr¨om. Orbit and bundle stratification and notation, Paper I gives an introduction to stratification for orbits and bundles of matrices, matrix these two permutation matrices are provided. Paper II gives a short introduction to stratification of orbits

Johansson, Stefan

171

Some considerations of matrix equations using the concept of reproductivity  

E-print Network

In this paper we analyse Cline's matrix equation, generalized Penrose's matrix system and a matrix system for k-commutative {1}-inverses. We determine reproductive and non-reproductive general solutions of analysed matrix equation and analysed matrix systems.

Malesevic, Branko

2011-01-01

172

Bayesian analysis of matrix normal graphical models  

PubMed Central

We present Bayesian analyses of matrix-variate normal data with conditional independencies induced by graphical model structuring of the characterizing covariance matrix parameters. This framework of matrix normal graphical models includes prior specifications, posterior computation using Markov chain Monte Carlo methods, evaluation of graphical model uncertainty and model structure search. Extensions to matrix-variate time series embed matrix normal graphs in dynamic models. Examples highlight questions of graphical model uncertainty, search and comparison in matrix data contexts. These models may be applied in a number of areas of multivariate analysis, time series and also spatial modelling. PMID:22822246

Wang, Hao; West, Mike

2009-01-01

173

On a quadratic matrix equation associated with an M-matrix  

Microsoft Academic Search

We study the quadratic matrix equation X, EX F = 0, where E is diagonal and F is an M-matrix. Quadratic matrix equations of this type arise in noisy Wiener{Hopf problems for Markov chains. The solution of practical interest is a particular M-matrix solution. The existence and uniqueness of M-matrix solutions and numerical methods for nding the desired M-matrix solution

Chun-hua Guo

2003-01-01

174

A combinatorial extracellular matrix platform identifies cell-extracellular matrix interactions that correlate with metastasis  

E-print Network

Extracellular matrix interactions have essential roles in normal physiology and many pathological processes. Although the importance of extracellular matrix interactions in metastasis is well documented, systematic approaches ...

Reticker-Flynn, Nathan E.

175

Corrosion of Titanium Matrix Composites  

SciTech Connect

The corrosion behavior of unalloyed Ti and titanium matrix composites containing up to 20 vol% of TiC or TiB{sub 2} was determined in deaerated 2 wt% HCl at 50, 70, and 90 degrees C. Corrosion rates were calculated from corrosion currents determined by extrapolation of the tafel slopes. All curves exhibited active-passive behavior but no transpassive region. Corrosion rates for Ti + TiC composites were similar to those for unalloyed Ti except at 90 degrees C where the composites were slightly higher. Corrosion rates for Ti + TiB{sub 2} composites were generally higher than those for unalloyed Ti and increased with higher concentrations of TiB{sub 2}. XRD and SEM-EDS analyses showed that the TiC reinforcement did not react with the Ti matrix during fabrication while the TiB{sub 2} reacted to form a TiB phase.

Covino, B.S., Jr.; Alman, D.E.

2002-09-22

176

Interstellar problems and matrix solutions  

NASA Technical Reports Server (NTRS)

The application of the matrix isolation technique to interstellar problems is described. Following a brief discussion of the interstellar medium (ISM), three areas are reviewed in which matrix experiments are particularly well suited to contribute the information which is sorely needed to further understanding of the ISM. The first involves the measurement of the spectroscopic properties of reactive species. The second is the determination of reaction rates and the elucidation of reaction pathways involving atoms, radicals, and ions which are likely to interact on grain surfaces and in grain mantles. The third entails the determiantion of the spectroscopic, photochemical, and photophysical properties of interstellar and cometary ice analogs. Significant, but limited, progress has been made in these three areas, and a tremendous amount of work is required to fully address the variety of unique chemical and spectroscopic questions posed by the astronomical observations.

Allamandola, Louis J.

1987-01-01

177

Interstellar problems and matrix solutions.  

PubMed

The application of the matrix isolation technique, which is but one of the experimental techniques pioneered in George Pimentel's laboratories, to interstellar problems is described. Following a brief discussion of the interstellar medium (ISM) three areas are reviewed in which matrix experiments are particularly well-suited to contribute the information which is sorely needed to further our understanding of the ISM. The first involves the measurement of the spectroscopic properties of reactive species. The second is the determination of reaction rates and the elucidation of reaction pathways involving atoms, radicals and ions which are likely to interact on grain surfaces and in grain mantles. The third entails the determination of the spectroscopic, photochemical and photophysical properties of interstellar and cometary ice analogs. Significant, but limited, progress has been made in these three areas and a tremendous amount of work is required to fully address the variety of unique chemical and spectroscopic questions posed by the astronomical observations. PMID:11543155

Allamandola, L J

1987-03-01

178

APPROVED DATE 1 Matrix ORNL  

E-print Network

05-26-2011 APPROVED DATE 1 Matrix ­ ORNL 2 Post Doc ­ OPS 3 Post Doc ­ Other 4 Visiting Scientist 5 MSc. S. Voisin3 Post doc. ES&H G. Rowland, Manager L. Fagan HFIR ES&H P. Abston HFIR/SNS ES&H Neutron. Mavila-Chathoth3 Post doc. CNCS G. Ehlers Lead Scientist A. Podlesnyak Scientist P. Cutler* Scientific

179

Matrix models and graph colouring  

NASA Astrophysics Data System (ADS)

We study an edge-colouring problem on random planar graphs which is one of the simplest vertex models that may be analyzed by standard methods of large N matrix models. The main features of the saddle point solution and its critical behaviour are described. At the critical value of the coupling gcr the eigen value density u(?)M is found to vanish at the border of the support as ?-a2/3.

Cicuta, Giovanni M.; Molinari, Luca; Montaldi, Emilio

1993-06-01

180

Colon Multiple Primary Rules Matrix  

Cancer.gov

Colon Multiple Primary Rules – Matrix C180-C189 (Excludes lymphoma and leukemia M9590 – 9989 and Kaposi sarcoma M9140) * P r e p ar e o n e abs tr a c t. U s e t h e hi s t o lo g y c o di ng r u le s t o as s i gn th e ap pr o p

181

Kidney Multiple Primary Rules Matrix  

Cancer.gov

Kidney Multiple Primary Rules – Matrix C649 (Excludes lymphoma and leukemia M9590 – 9989 and Kaposi sarcoma M9140) * P r e p ar e o n e abs tr a c t. U s e t h e hi s t o lo g y c o di ng r u le s t o as s i gn th e ap pr o p r iat

182

The asymmetric ABAB matrix model  

NASA Astrophysics Data System (ADS)

In this letter, it is pointed out that the two-matrix model defined by the action S = ½(trA2 + trB2) - [(?A)/(4)]trA4 - [(?B)/(4)]trB4 - [(?)/(2)]tr(AB)2 can be solved in the large-N limit using a generalization of the solution of Kazakov and Zinn-Justin (who considered the symmetric case ?A = ?B). This model could have useful applications to 3D Lorentzian gravity.

Zinn-Justin, P.

2003-12-01

183

Extracellular Matrix Production by Osteoblasts  

NASA Technical Reports Server (NTRS)

In this graduate course lecture, the basic biology of osteoblasts will be explored. Cells of the osteoblast lineage arise from the mesoderm and neural crest, showing remarkable plasticity with respect to differentiation. Basic mechanisms involved in the proliferation, differentiation, and survival of osteoblasts will be described. The extracellular matrix (ECM) is known to be both thc main product of the mature osteoblast, and an effective regulator of osteoblast function. The impact of these interactions on skeletal biology will be discussed.

Globus, Ruth

2003-01-01

184

Melanoma Multiple Primary Rules Matrix  

Cancer.gov

Cutaneous Melanoma Multiple Primary Rules – Matrix C440 – C449 (Excludes melanoma of any other site) * P r e p ar e o n e abs tr a c t. U s e t h e hi s t o lo g y c o di ng r u le s t o as s i gn th e ap pr o p r iat e h is to lo

185

Radiation resistant ceramic matrix composites  

Microsoft Academic Search

Ceramic matrix composites are of interest for nuclear applications because of their high-temperature properties, corrosion resistance, fracture toughness relative to monolithic ceramics, and low neutron activation and after heat. Evaluations of the radiation resistance of commercially available SiC\\/SiC composites have revealed their promise for this application, but also the need for further development to achieve the desired performance. This paper

R. H. Jones; D. Steiner; H. L. Heinisch; G. A. Newsome; H. M. Kerch

1997-01-01

186

Tough high performance composite matrix  

NASA Technical Reports Server (NTRS)

This invention is a semi-interpentrating polymer network which includes a high performance thermosetting polyimide having a nadic end group acting as a crosslinking site and a high performance linear thermoplastic polyimide. Provided is an improved high temperature matrix resin which is capable of performing in the 200 to 300 C range. This resin has significantly improved toughness and microcracking resistance, excellent processability, mechanical performance, and moisture and solvent resistances.

Pater, Ruth H. (inventor); Johnston, Norman J. (inventor)

1994-01-01

187

Link Prediction via Matrix Factorization  

Microsoft Academic Search

\\u000a We propose to solve the link prediction problem in graphs using a supervised matrix factorization approach. The model learns\\u000a latent features from the topological structure of a (possibly directed) graph, and is shown to make better predictions than\\u000a popular unsupervised scores. We show how these latent features may be combined with optional explicit features for nodes or\\u000a edges, which yields

Aditya Krishna Menon; Charles Elkan

188

Covariance matrix criterion for separability  

NASA Astrophysics Data System (ADS)

We review an approach to the separability problem using covariance matrices of locally measurable observables. This approach leads to a strong entanglement criterion which we call covariance matrix criterion (CMC). We consider some corollaries of the CMC that in general allow to detect many bound entangled states. In particular we give a new example which sheds some light on the connections between different entanglement criteria derived from the general CMC.

Gittsovich, O.; Gühne, O.; Hyllus, P.; Eisert, J.

2009-04-01

189

Fast polar decomposition of an arbitrary matrix  

NASA Technical Reports Server (NTRS)

The polar decomposition of an m x n matrix A of full rank, where m is greater than or equal to n, can be computed using a quadratically convergent algorithm. The algorithm is based on a Newton iteration involving a matrix inverse. With the use of a preliminary complete orthogonal decomposition the algorithm can be extended to arbitrary A. How to use the algorithm to compute the positive semi-definite square root of a Hermitian positive semi-definite matrix is described. A hybrid algorithm which adaptively switches from the matrix inversion based iteration to a matrix multiplication based iteration due to Kovarik, and to Bjorck and Bowie is formulated. The decision when to switch is made using a condition estimator. This matrix multiplication rich algorithm is shown to be more efficient on machines for which matrix multiplication can be executed 1.5 times faster than matrix inversion.

Higham, Nicholas J.; Schreiber, Robert S.

1988-01-01

190

Introduction Matrix multiplication based linear algebra  

E-print Network

Introduction Matrix multiplication based linear algebra Computing the characteristic polynomial #12;Introduction Matrix multiplication based linear algebra Computing the characteristic polynomial Conclusion and perspectives Introduction Dense Linear Algebra over a Field: one of the usual models

Pernet, Clément

191

Causal scattering matrix in quantum electrodynamics  

E-print Network

A causal scattering matrix of quantum electrodynamics is constructed by means of chronological product of Lagrangians where the fields have the different arguments. This scattering matrix is a convergent series and does not contain the diverging integrals.

Yury M. Zinoviev

2012-09-27

192

Teaching Tip: When a Matrix and Its Inverse Are Stochastic  

ERIC Educational Resources Information Center

A stochastic matrix is a square matrix with nonnegative entries and row sums 1. The simplest example is a permutation matrix, whose rows permute the rows of an identity matrix. A permutation matrix and its inverse are both stochastic. We prove the converse, that is, if a matrix and its inverse are both stochastic, then it is a permutation matrix.

Ding, J.; Rhee, N. H.

2013-01-01

193

Analytic approximation of matrix functions in Lp  

Microsoft Academic Search

We consider the problem of approximation of matrix functions of class Lp on the unit circle by matrix functions ana- lytic in the unit disk in the norm of Lp, 2 p < 1. For an m n matrix function in Lp, we consider the Hankel operator H : Hq(Cn) ! H2 (C m), 1=p + 1=q = 1=2. It

Laurent Baratchart; F. L. Nazarov; V. V. Peller

2009-01-01

194

Metal-matrix composites: Status and prospects  

NASA Technical Reports Server (NTRS)

Applications of metal matrix composites for air frames and jet engine components are discussed. The current state of the art in primary and secondary fabrication is presented. The present and projected costs were analyzed to determine the cost effectiveness of metal matrix composites. The various types of metal matrix composites and their characteristics are described.

1974-01-01

195

A note on quantization of matrix models  

Microsoft Academic Search

The issue of non-perturbative background independent quantization of matrix models is addressed. The analysis is carried out by considering a simple matrix model which is a matrix extension of ordinary mechanics reduced to 0 dimension. It is shown that this model has an ordinary mechanical system evolving in time as a classical solution. But in this treatment the action principle

Artem Starodubtsev

2003-01-01

196

The hat matrix for smoothing splines  

Microsoft Academic Search

The matrix which transforms the data vector to the vector of fitted values for smoothing splines is termed the hat matrix. This matrix is shown to have many of the same properties, and is seen to play the same role in the variances and covariances of the residuals, as its regression analysis counterpart. This fact is utilized to propose several

R. L. Eubank

1984-01-01

197

New vibrostable multipass matrix system for TDLAS  

Microsoft Academic Search

The perspective version of the multipass matrix system for use in diode laser spectrometers is worked out with the purpose of atmospheric monitoring at different altitudes. The new matrix system owing to its vibrostability allows making measurements in conditions of the high vibration on board of aircraft and helicopter. In this modification all best properties of the known matrix four-objective

Semen M. Chernin; Andrey G. Berezin; Oleg V. Ershov; Alexander I. Nadezhdinskii; Dimitry B. Stavrovsky

1999-01-01

198

Matrix metalloproteinases: old dogs with new tricks  

Microsoft Academic Search

The matrix metalloproteinase family in humans comprises 23 enzymes, which are involved in many biological processes and diseases. It was previously thought that these enzymes acted only to degrade components of the extracellular matrix, but this view has changed with the discovery that non-extracellular-matrix molecules are also substrates.

Robert PT Somerville; Samantha A Oblander; Suneel S Apte

2003-01-01

199

Effect of Matrix Cracks on Damping in Unidirectional and Cross-Ply Ceramic Matrix Composites  

Microsoft Academic Search

The paper elucidates the methodsof estimating damping in ceramic matrix composites (CMC) with matrix cracks. Unidirectional composites with bridging matrix cracks and cross-ply laminates with tunneling cracks in transverse layers and bridging cracks in longitudinal layers are considered. It is shown that bridging matrix cracksdra matically increase damping in unidirectional CMC due to a dissipation of energy along damaged sections

Victor Birman; Larry W. Byrd

2002-01-01

200

Conditions for matrix crack deflection at an interface in ceramic matrix composites  

Microsoft Academic Search

This paper describes a numerical approach developed to simulate the mechanism of matrix crack deflection at the fibre\\/matrix interface in brittle matrix composites. For this purpose, the fracture behaviour of a unit cell (microcomposite) consisting of a single fibre surrounded by a cylindrical tube of matrix was studied with the help of a finite element model. A fracture mechanics approach

E. Martin; P. W. M. Peters; D. Leguillon; J. M. Quenisset

1998-01-01

201

Cell-matrix adhesions in 3D.  

PubMed

Cells in a three-dimensional (3D) extracellular matrix environment often display different properties and behavior compared to cells cultured on a two-dimensional (2D) substrate. Recent studies characterizing the cell-matrix adhesions formed by cells within a 3D matrix have arrived at contradictory conclusions regarding the presence and composition of adhesions. Here we review this literature, and provide a comparative compilation of information found in published studies from the 3D cell-matrix adhesion field in order to identify shared and divergent conclusions and conceptually important areas that require further research. Although there is a general consensus that discrete cell-matrix adhesions exist in various 3D matrix environments, there are specific exceptions, particularly in cells undergoing amoeboid migration. There are also technical issues to consider when imaging adhesions in 3D matrix; for example, over-expression of a cytoskeletal cell adhesion component can potentially cloud the visualization of adhesions and even alter the mode of cell migration. Properties such as stiffness and local matrix topography may also affect the composition of cell-matrix adhesions. For example, even though cells contain integrin-based 3D adhesions, there can be substantial variability within these adhesions in the presence of force-dependent cytoskeletal components such as vinculin. These new findings and ideas provide promising new leads for understanding the regulation and function of cell-matrix adhesions in 3D matrix. PMID:21723391

Harunaga, Jill S; Yamada, Kenneth M

2011-09-01

202

Step Towards Real Life Matrix  

NSDL National Science Digital Library

This article from New Scientist News discusses the possibility that Sony might be able to develop a real life matrix. That is, people may be able to watch movies and play computer games in which they can also get to smell, taste and perhaps even feel things. The prospect was raised by Sony's approval for a patent on a device for transmitting sensory data directly into the human brain. The author discusses how this device might work but notes that Sony declined New Scientist's request for an interview with the inventor. If the method described by Sony works, the author speculates on its uses in research and medicine.

203

Brain Extracellular Matrix in Neurodegeneration  

PubMed Central

The role of extracellular matrix (ECM) in neurological development, function and degeneration has evolved from a simplistic physical adhesion to a system of intricate cellular signaling. While most cells require ECM adhesion to survive, it is now clear that differentiated function is intimately dependent upon cellular interaction with the ECM. Therefore, it is not surprising that the ECM is increasingly found to be involved in the enigmatic process of neurodegeneration. Descriptive studies of human neurodegenerative disorders and experimental studies of animal models of neurodegeneration have begun to define potential mechanisms of ECM disruption that can lead to synaptic and neuronal loss. PMID:18662234

Bonneh-Barkay, Dafna; Wiley, Clayton A.

2009-01-01

204

Matrix metalloproteinases and cardiovascular diseases  

PubMed Central

Matrix metalloproteinases (MMPs) are extracellular enzymes that are important in many physiologic and pathologic processes. Their activity is regulated mainly by tissue inhibitors of metalloproteinases (TIMPs). MMPs expression is related with the classical cardiovascular risk factors as well as with inflammation. They play a central role in atherosclerosis, plaque formation, platelet aggregation, acute coronary syndrome, restenosis, aortic aneurysms and peripheral vascular disease. Many studies have shown that commonly prescribed antihypertensive medications, glitazones and statins may influence MMPs activity. The aim of the review is to present literature data on the role of MMPs and their inhibitors in cardiovascular disease. PMID:19561775

Papazafiropoulou, A; Tentolouris, N

2009-01-01

205

Fiber-matrix interface failures  

NASA Technical Reports Server (NTRS)

Interface fractures of aluminum-graphite composites under transverse loading are expected to occur within the graphite fibers, but very near the interface. Residual stresses in aluminum, reinforced with the new high modulus pitch-based fibers, are much lower than would be expected based on simple elasticity calculations. The excess stress may be relaxed by shearing internal to the fibers or at the interface rather than by plastic flow of the matrix. The internal shearing also occurs during repeated thermal cycling of these composites; the fibers are repeatedly intruded, then extruded, during repeated temperature excursions.

Rabenberg, Lew; Marcus, Harris L.; Park, Hun Sub; Zong, Gui Sheng; Brown, Lloyd D.

1989-01-01

206

Matrix management for aerospace 2000  

NASA Technical Reports Server (NTRS)

The martix management approach to program management is an organized effort for attaining program objectives by defining and structuring all elements so as to form a single system whose parts are united by interaction. The objective of the systems approach is uncompromisingly complete coverage of the program management endeavor. Starting with an analysis of the functions necessary to carry out a given program, a model must be defined; a matrix of responsibility assignment must be prepared; and each operational process must be examined to establish how it is to be carried out and how it relates to all other processes.

Mccarthy, J. F., Jr.

1980-01-01

207

Regenerator matrix physical property data  

NASA Technical Reports Server (NTRS)

Among several cellular ceramic structures manufactured by various suppliers for regenerator application in a gas turbine engine, three have the best potential for achieving durability and performance objectives for use in gas turbines, Stirling engines, and waste heat recovery systems: (1) an aluminum-silicate sinusoidal flow passage made from a corrugated wate paper process; (2) an extruded isosceles triangle flow passage; and (3) a second generation matrix incorporating a square flow passage formed by an embossing process. Key physical and thermal property data for these configurations presented include: heat transfer and pressure drop characteristics, compressive strength, tensile strength and elasticity, thermal expansion characteristics, chanical attack, and thermal stability.

Fucinari, C. A.

1980-01-01

208

Random Matrix Theory and Econophysics  

NASA Astrophysics Data System (ADS)

Random Matrix Theory (RMT) [1] is used in many branches of physics as a ``zero information hypothesis''. It describes generic behavior of different classes of systems, while deviations from its universal predictions allow to identify system specific properties. We use methods of RMT to analyze the cross-correlation matrix C of stock price changes [2] of the largest 1000 US companies. In addition to its scientific interest, the study of correlations between the returns of different stocks is also of practical relevance in quantifying the risk of a given stock portfolio. We find [3,4] that the statistics of most of the eigenvalues of the spectrum of C agree with the predictions of RMT, while there are deviations for some of the largest eigenvalues. We interpret these deviations as a system specific property, e.g. containing genuine information about correlations in the stock market. We demonstrate that C shares universal properties with the Gaussian orthogonal ensemble of random matrices. Furthermore, we analyze the eigenvectors of C through their inverse participation ratio and find eigenvectors with large ratios at both edges of the eigenvalue spectrum - a situation reminiscent of localization theory results. This work was done in collaboration with V. Plerou, P. Gopikrishnan, T. Guhr, L.A.N. Amaral, and H.E Stanley and is related to recent work of Laloux et al.. 1. T. Guhr, A. Müller Groeling, and H.A. Weidenmüller, ``Random Matrix Theories in Quantum Physics: Common Concepts'', Phys. Rep. 299, 190 (1998). 2. See, e.g. R.N. Mantegna and H.E. Stanley, Econophysics: Correlations and Complexity in Finance (Cambridge University Press, Cambridge, England, 1999). 3. V. Plerou, P. Gopikrishnan, B. Rosenow, L.A.N. Amaral, and H.E. Stanley, ``Universal and Nonuniversal Properties of Cross Correlations in Financial Time Series'', Phys. Rev. Lett. 83, 1471 (1999). 4. V. Plerou, P. Gopikrishnan, T. Guhr, B. Rosenow, L.A.N. Amaral, and H.E. Stanley, ``Random Matrix Theory Analysis of Diffusion in Stock Price Dynamics, preprint

Rosenow, Bernd

2000-03-01

209

Spatially-explicit matrix models  

Microsoft Academic Search

This paper is concerned with mathematical analysis of the `critical\\u000a domain-size' problem for structured populations. Space is introduced\\u000a explicitly into matrix models for stage-structured populations. Movement\\u000a of individuals is described by means of a dispersal kernel. The\\u000a mathematical analysis investigates conditions for existence, stability\\u000a and uniqueness of equilibrium solutions as well as some bifurcation\\u000a behaviors. These mathematical results are linked

Frithjof Lutscher; Mark A. Lewis

2004-01-01

210

Characterization of Metal Matrix Composites  

NASA Technical Reports Server (NTRS)

Experimental methods were developed, adapted, and applied to the characterization of a metal matrix composite system, namely, silicon carbide/aluminim (SCS-2/6061 Al), and its constituents. The silicon carbide fiber was characterized by determining its modulus, strength, and coefficient of thermal expansion. The aluminum matrix was characterized thermomechanically up to 399 C (750 F) at two strain rates. The unidirectional SiC/Al composite was characterized mechanically under longitudinal, transverse, and in-plane shear loading up to 399 C (750 F). Isothermal and non-isothermal creep behavior was also measured. The applicability of a proposed set of multifactor thermoviscoplastic nonlinear constitutive relations and a computer code was investigated. Agreement between predictions and experimental results was shown in a few cases. The elastoplastic thermomechanical behavior of the composite was also described by a number of new analytical models developed or adapted for the material system studied. These models include the rule of mixtures, composite cylinder model with various thermoelastoplastic analyses and a model based on average field theory. In most cases satisfactory agreement was demonstrated between analytical predictions and experimental results for the cases of stress-strain behavior and thermal deformation behavior at different temperatures. In addition, some models yielded detailed three-dimensional stress distributions in the constituents within the composite.

Daniel, I. M.; Chun, H. J.; Karalekas, D.

1994-01-01

211

Uniform-burning matrix burner  

DOEpatents

Computer simulation was used in the development of an inward-burning, radial matrix gas burner and heat pipe heat exchanger. The burner and exchanger can be used to heat a Stirling engine on cloudy days when a solar dish, the normal source of heat, cannot be used. Geometrical requirements of the application forced the use of the inward burning approach, which presents difficulty in achieving a good flow distribution and air/fuel mixing. The present invention solved the problem by providing a plenum with just the right properties, which include good flow distribution and good air/fuel mixing with minimum residence time. CFD simulations were also used to help design the primary heat exchanger needed for this application which includes a plurality of pins emanating from the heat pipe. The system uses multiple inlet ports, an extended distance from the fuel inlet to the burner matrix, flow divider vanes, and a ring-shaped, porous grid to obtain a high-temperature uniform-heat radial burner. Ideal applications include dish/Stirling engines, steam reforming of hydrocarbons, glass working, and any process requiring high temperature heating of the outside surface of a cylindrical surface.

Bohn, Mark S. (Golden, CO); Anselmo, Mark (Arvada, CO)

2001-01-01

212

Thermoplastic matrix composite processing model  

NASA Technical Reports Server (NTRS)

The effects the processing parameters pressure, temperature, and time have on the quality of continuous graphite fiber reinforced thermoplastic matrix composites were quantitatively accessed by defining the extent to which intimate contact and bond formation has occurred at successive ply interfaces. Two models are presented predicting the extents to which the ply interfaces have achieved intimate contact and cohesive strength. The models are based on experimental observation of compression molded laminates and neat resin conditions, respectively. Identified as the mechanism explaining the phenomenon by which the plies bond to themselves is the theory of autohesion (or self diffusion). Theoretical predictions from the Reptation Theory between autohesive strength and contact time are used to explain the effects of the processing parameters on the observed experimental strengths. The application of a time-temperature relationship for autohesive strength predictions is evaluated. A viscoelastic compression molding model of a tow was developed to explain the phenomenon by which the prepreg ply interfaces develop intimate contact.

Dara, P. H.; Loos, A. C.

1985-01-01

213

Simplicial matrix-tree theorems  

E-print Network

?(G)= ? 1 ···? n?1 n . (2) For 1 ? i ? n,letL i be the reduced Laplacian obtained from L by deleting the i th row and i th column. Then ?(G)=detL i . Well-known corollaries of the Matrix-Tree Theorem include Cayley’s formula [9] (1) ?(K n )=n n?2... , introducing indeterminates x 1 ,...,x n and set- ting e ij = x i x j for all i, j yields the Cayley-Pr¨ufer Theorem, which enumerates spanning trees of K n by their degree sequences: (3) summationdisplay T?T (G) n productdisplay i=1 x deg T (i) i = x 1 ···x n...

Duval, Art M.; Klivans, Caroline J.; Martin, Jeremy L.

2009-01-01

214

Convex nonnegative matrix factorization with manifold regularization.  

PubMed

Nonnegative Matrix Factorization (NMF) has been extensively applied in many areas, including computer vision, pattern recognition, text mining, and signal processing. However, nonnegative entries are usually required for the data matrix in NMF, which limits its application. Besides, while the basis and encoding vectors obtained by NMF can represent the original data in low dimension, the representations do not always reflect the intrinsic geometric structure embedded in the data. Motivated by manifold learning and Convex NMF (CNMF), we propose a novel matrix factorization method called Graph Regularized and Convex Nonnegative Matrix Factorization (GCNMF) by introducing a graph regularized term into CNMF. The proposed matrix factorization technique not only inherits the intrinsic low-dimensional manifold structure, but also allows the processing of mixed-sign data matrix. Clustering experiments on nonnegative and mixed-sign real-world data sets are conducted to demonstrate the effectiveness of the proposed method. PMID:25523040

Hu, Wenjun; Choi, Kup-Sze; Wang, Peiliang; Jiang, Yunliang; Wang, Shitong

2015-03-01

215

A New Proposal for Matrix Theory  

E-print Network

We explain the motivation and main ideas underlying our proposal for a Lagrangian for Matrix Theory based on sixteen supercharges. Starting with the pedagogical example of a bosonic matrix theory we describe the appearance of a continuum spacetime geometry from a discrete, and noncommutative, spacetime with both Lorentz and Yang-Mills invariances. We explain the appearance of large N ground states with Dbranes and elucidate the principle of matrix Dbrane democracy at finite N. Based on the underlying symmetry algebras that hold at both finite and infinite N, we show why the supersymmetric matrix Lagrangian we propose does not belong to the class of supermatrix models which includes the BFSS and IKKT Matrix Models. We end with a preliminary discussion of a path integral prescription for the Hartle-Hawking wavefunction of the Universe derived from Matrix Theory.

Shyamoli Chaudhuri

2005-07-24

216

Design of tabular excavations in foliated rock: an integrated numerical  

E-print Network

the intact strength of the orebody and host rock, and by the pillars that separate the open stope from previously developed openings. In addition, cable bolting techniques and the use of backfill provides extra

217

Calving of large tabular icebergs from ice shelf rift systems  

Microsoft Academic Search

We used Interferometric Synthetic Aperture Radar to study the detachment process that allowed two large icebergs to calve from the Ross Ice Shelf, Antarctica. Time series of rift geometries indicate that rift widths increased steadily, whereas rift lengths increased episodically through several discrete rift-tip propagation events. We also conducted modeling experiments constrained by the observed rift geometry. Both the observations

Ian Joughin; Douglas R. MacAyeal

2005-01-01

218

A heuristic block coordinate descent approach for controlled tabular ...  

E-print Network

a census), which results in sets of tables, usually with a large number of cells. NSAs are obliged by ...... English translation of the original paper ... Language for Optimal CTA, Lecture Notes in Computer Science, 5262, 1–12. [8] Chinneck, J.W.

2010-11-05

219

Revisiting Bertin Matrices: New Interactions for Crafting Tabular Visualizations  

E-print Network

NORWAY POLAND PORTUGAL RUSSIA SPAIN SWEDEN UNITEDKINGDOM HOUSEHOLD INCOME WOMEN'S SUFFRAGE DATE AGAINST NOT AS A NEIGHBOUR: HOMOSEXUALS ATTEND CHURCH AT LEAST ONCE A WEEK WOMEN'S SUFFRAGE DATE CZECHREPUBLIC FINLANDPolPorRusSpaSweUni Household in Women's suf Against coha Belief in God Confidence Confidence Confidence Confidence Confidence

Paris-Sud XI, Université de

220

Matrix Bases for Star Products: a Review  

E-print Network

We review the matrix bases for a family of noncommutative $\\star$ products based on a Weyl map. These products include the Moyal product, as well as the Wick-Voros products and other translation invariant ones. We also review the derivation of Lie algebra type star products, with adapted matrix bases. We discuss the uses of these matrix bases for field theory, fuzzy spaces and emergent gravity.

Fedele Lizzi; Patrizia Vitale

2014-08-15

221

Text Retrieval Using Sparsified Concept Decomposition Matrix  

Microsoft Academic Search

\\u000a We examine text retrieval strategies using the sparsified concept decomposition matrix. The centroid vector of a tightly structured\\u000a text collection provides a general description of text documents in that collection. The union of the centroid vectors forms\\u000a a concept matrix. The original text data matrix can be projected into the concept space spanned by the concept vectors. We\\u000a propose a

Jing Gao; Jun Zhang

2004-01-01

222

Matrix Bases for Star Products: a Review  

NASA Astrophysics Data System (ADS)

We review the matrix bases for a family of noncommutative star products based on a Weyl map. These products include the Moyal product, as well as the Wick-Voros products and other translation invariant ones. We also review the derivation of Lie algebra type star products, with adapted matrix bases. We discuss the uses of these matrix bases for field theory, fuzzy spaces and emergent gravity.

Lizzi, Fedele; Vitale, Patrizia

2014-08-01

223

Imposing causality on a matrix model  

E-print Network

We introduce a new matrix model that describes Causal Dynamical Triangulations (CDT) in two dimensions. In order to do so, we introduce a new, simpler definition of 2D CDT and show it to be equivalent to the old one. The model makes use of ideas from dually weighted matrix models, combined with multi-matrix models, and can be studied by the method of character expansion.

Dario Benedetti; Joe Henson

2009-06-28

224

Solution of matrix equations using sparse techniques  

NASA Technical Reports Server (NTRS)

The solution of large systems of matrix equations is key to the solution of a large number of scientific and engineering problems. This talk describes the sparse matrix solver developed at Langley which can routinely solve in excess of 263,000 equations in 40 seconds on one Cray C-90 processor. It appears that for large scale structural analysis applications, sparse matrix methods have a significant performance advantage over other methods.

Baddourah, Majdi

1994-01-01

225

Symmetric functions and the Vandermonde matrix  

NASA Astrophysics Data System (ADS)

This work deduces the lower and the upper triangular factors of the inverse of the Vandermonde matrix using symmetric functions and combinatorial identities. The L and U matrices are in turn factored as bidiagonal matrices. The elements of the upper triangular matrices in both the Vandermonde matrix and its inverse are obtained recursively. The particular value xi=1+q+...+qi-1 in the indeterminates of the Vandermonde matrix is investigated and it leads to q-binomial and q-Stirling matrices. It is also shown that q-Stirling matrices may be obtained from the Pascal matrix.

Oruc, Halil; Akmaz, Hakan K.

2004-11-01

226

Multiscale Modeling of Ceramic Matrix Composites  

NASA Technical Reports Server (NTRS)

Results of multiscale modeling simulations of the nonlinear response of SiC/SiC ceramic matrix composites are reported, wherein the microstructure of the ceramic matrix is captured. This micro scale architecture, which contains free Si material as well as the SiC ceramic, is responsible for residual stresses that play an important role in the subsequent thermo-mechanical behavior of the SiC/SiC composite. Using the novel Multiscale Generalized Method of Cells recursive micromechanics theory, the microstructure of the matrix, as well as the microstructure of the composite (fiber and matrix) can be captured.

Bednarcyk, Brett A.; Mital, Subodh K.; Pineda, Evan J.; Arnold, Steven M.

2015-01-01

227

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

228

New Solvable Nonlinear Matrix Evolution Equations  

Microsoft Academic Search

We introduce an extension of the factorization-decomposition technique that allows us to manufacture new solvable nonlinear matrix evolution equations. Several examples of such equations are reported.

M BRUSCHI

2005-01-01

229

Regulation of extracellular matrix biosynthesis by matrix components  

SciTech Connect

The authors have previously shown that smooth muscle cells derived from healthy rabbit aortic media synthesize less collagen and fibronectin when grown on culture dishes coated with rabbit plasma fibronectin. In these cultures noncollagen protein synthesis was not affected, suggesting a specific regulatory mechanism. Their current studies expand this observation by examining the ability of proteolytically derived, specific domains of plasma fibronectin to effect decreases in collagen and fibronectin synthesis by cultured arterial smooth muscle. Rabbit plasma fibronectin was digested with bovine ..cap alpha..-chymotrypsin by the method of Hahn and Yamada. The resultant proteolytic fragments were separated by their ability to bind to gelatin-agarose. Culture dishes were coated with either (1) cell binding fragment of fibronectin, (2) gelatin binding fragment, (3) intact fibronectin, (4) type I collagen derived from lathyritic rat skin or (5) bovine serum albumin. Preconfluent cultures were labeled with /sup 3/H-Pro for 24 hr. Fibronectin synthesis was determined by immunoprecipitation of /sup 3/H-fibronectin. Collagen synthesis was measured by monitoring /sup 3/H-Hyp formation. Decreased collagen and fibronectin synthesis was evident in cells grown on intact fibronectin, cell binding fragment of fibronectin and type I collagen. Cells plated on gelatin binding fragment synthesized both collagen and fibronectin at levels comparable to cells on albumin coated dishes. They conclude that the regulatory activity of fibronectin on matrix biosynthesis resides on the cell binding domain of the molecule and that type I collagen can exert a similar effect.

Holderbaum, D.; Ehrhart, L.A.

1986-03-01

230

Effectiveness of metal matrix and ceramic matrix composites as orbital debris shield materials  

NASA Technical Reports Server (NTRS)

The effectiveness of two metal matrix composites and one ceramic matrix material in defeating hypervelocity impacts at about 3.8 km/s are evaluated to determine the potential of these composites as spacecraft shield materials. The metal matrix composites investigated consist of SiC particles (70 percent by volume) in an aluminum matrix and Al2O3 particles (50 percent by volume) in an Al matrix. The ceramic composite consists of ZrB2 platelets in a ZrC matrix. Both the metal matrix and ceramic matrix composites are found to perform as well or better than 6061-T6 aluminum, which is presently used in the Whipple type bumper shield of Space Station Freedom. Test results indicate that the composites tested may have applications as micrometeoroid/orbital debris shield materials.

Mcgill, Preston B.; Mount, Angela R.

1992-01-01

231

Fragmentation of extracellular matrix by hypochlorous acid.  

PubMed Central

The interaction of extracellular matrix with cells regulates their adhesion, migration and proliferation, and it is believed that damage to vascular matrix components is a factor in the development of atherosclerosis. Evidence has been provided for a role for the haem enzyme MPO (myeloperoxidase), released by activated monocytes (and possibly macrophages), in oxidative events within the artery wall. As MPO is released extracellularly, and is highly basic, it might be expected to associate with poly-anionic matrix components thereby localizing damage to these materials. In this study the reaction of the MPO-derived oxidant hypochlorous acid (HOCl) with extracellular matrix from vascular smooth muscle cells and healthy pig arteries has been examined. HOCl is rapidly consumed by such matrix samples, with the formation of matrix-derived chloramines or chloramides. The yield of these intermediates increases with HOCl dose. These materials undergo a time- and temperature-dependent decay, which parallels the release of sugar and protein components from the treated matrix, consistent with these species being important intermediates. Matrix damage is enhanced by species that increase chloramine/chloramide decomposition, with copper and iron ions being effective catalysts, and decreased by compounds which scavenge chloramines/chloramides, or species derived from them. The effect of such matrix modifications on cellular behaviour is poorly understood, though it is known that changes in matrix materials can have profound effects on cell adhesion, proliferation, growth and phenotype. The observed matrix modifications reported here may therefore modulate cellular behaviour in diseases such as atherosclerosis where MPO-derived oxidants are generated. PMID:12911330

Woods, Alan A; Davies, Michael J

2003-01-01

232

A compact method for matrix decomposition matrix inversion, and solution of simultaneous linear equations  

E-print Network

A COMPACT METHOD FOR MATRIX DECOMPOSITION MATRIX INVERSION, AND SOLUTION OF SIMULTANEOUS LINEAR EQUATIONS A Thesis By DONALD HENRY BANKER Submitted to the Graduate College of the Texas A6M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1966 Major Subject: MATHEMATICS A COMPACT METHOD FOR MATRIX DECOMPOSITION MATRIX INVERSION, AND SOLUTION OF SIMULTANEOUS LINEAR EQUATIONS A Thesis By DONALD HENRY BANKER Approved as to style...

Banker, Donald Henry

1966-01-01

233

Matrix metalloproteinases and matrix receptors in progression and reversal of kidney disease: therapeutic perspectives  

Microsoft Academic Search

Remodeling of extracellular matrix (ECM) is a key event in progression and reversal of kidney disease. This process results from synthesis of ECM components and their degradation, mostly by matrix metalloproteinases (MMPs). However, because of both the multiplicity of their targets that include non-matrix substrates, and the complexity of their regulation, MMPs may exert different, and even opposite, effects during

Pierre Ronco; Christos Chatziantoniou

2008-01-01

234

PRODUCT DISTANCE MATRIX OF A GRAPH AND SQUARED DISTANCE MATRIX OF A TREE  

E-print Network

. Sivasubramanian Let G be a strongly connected, weighted directed graph. We define a product distance (i, j for the determinant and the inverse of the product distance matrix. The edge orientation matrix of a directed tree for the inverse of the distance matrix of a tree was given by Graham and Lov´asz[6]. These two results have

Bapat, Ravindra B.

235

The design of the fibre-matrix interfacial zone in ceramic matrix composites  

Microsoft Academic Search

Ceramic matrix composites are tough when the fibre-matrix bonding is properly controlled during processing, via the use of an interphase. The interphase is either formed in situ as the result of fibre-matrix interactions or deposited on the fibre surface prior to composite fabrication. It has several key functions, including crack deflection, load transfer, diffusion barrier and residual stress relaxation. Four

Roger R. Naslain

1998-01-01

236

Strain and hysteresis by stochastic matrix cracking in ceramic matrix composites  

Microsoft Academic Search

A theory is presented to predict the stress\\/strain relations and unload\\/reload hysteresis behavior during the evolution of multiple matrix cracking in unidirectional fiber reinforced ceramic matrix composites (CMCs). The theory is based on the similarity between multiple matrix cracking and fiber fragmentation in a single fiber composite, and determines the crack and strain evolution as a function of the statistical

B. K. Ahn; W. A. Curtin

1997-01-01

237

New results on the separation of matrix eigenvalues and the clustering of matrix elements  

Microsoft Academic Search

The problem of separation of matrix eigenvalues is considered in this paper. Necessary and sufficient conditions are given for a matrix to have all eigenvalues contained in an open set defined on the complex plane by a separable polynomial ?(z1, z2). The problem of clustering of matrix elements is also considered. In this case, a set of matrices is identified,

Jerzy E. Kurek

1997-01-01

238

Singularity confinement for matrix discrete Painlevé equations  

NASA Astrophysics Data System (ADS)

We study the analytic properties of a matrix discrete system introduced by Cassatella and Mañas (2012 Stud. Appl. Math. 128 252-74). The singularity confinement for this system is shown to hold generically, i.e. in the whole space of parameters except possibly for algebraic subvarieties. This paves the way to a generalization of Painlevé analysis to discrete matrix models.

Cassatella-Contra, Giovanni A.; Mañas, Manuel; Tempesta, Piergiulio

2014-09-01

239

Boolean Matrix Multiplication and Transitive Closure  

Microsoft Academic Search

Arithmetic operations on matrices are applied to the problem of finding the transitive closure of a Boolean matrix. The best transitive closure algorithm known, due to Munro, is based on the matrix multiplication method of Strassen. We show that his method requires at most O(n? ¿ P(n)) bitwise operations, where ? = log27 and P(n) bounds the number of bitwise

Michael J. Fischer; Albert R. Meyer

1971-01-01

240

Risk Management using Dependency Stucture Matrix  

NASA Astrophysics Data System (ADS)

An efficient method based on dependency structure matrix (DSM) analysis is given for ranking risks in a complex system or process whose entities are mutually dependent. This rank is determined according to the element's values of the unique positive eigenvector which corresponds to the matrix spectral radius modeling the considered engineering system. For demonstration, the risk problem of NASA's robotic spacecraft is analyzed.

Petkovi?, Ivan

2011-09-01

241

Commercial processing of metal matrix composites  

Microsoft Academic Search

Discontinuously reinforced metal matrix composites are a class of materials that exhibit a blending of properties of the reinforcement and the matrix. The reinforcement can be ultra-high strength whiskers, short or chopped fibers or particles. Each of the reinforcements has property or cost attributes that dictate its use in a given situation. Commercial producers have concentrated on composites with particulate

William C Harrigan

1998-01-01

242

7 CFR 1770.17 - Expense matrix.  

Code of Federal Regulations, 2010 CFR

...Agriculture 12 2010-01-01 2010-01-01 false Expense matrix. 1770.17 Section 1770.17 Agriculture Regulations...BORROWERS Uniform System of Accounts § 1770.17 Expense matrix. The expense accounts shall be maintained by the...

2010-01-01

243

The Molecules of the Cell Matrix.  

ERIC Educational Resources Information Center

Cytoplasmic proteins form a highly structured yet changeable matrix that affects cell shape, division, motion, and transport of vesicles and organelles. Types of microfilaments, research techniques, actin and myosin, tumor cells, and other topics are addressed. Evidence indicates that the cell matrix might have a bearing on metabolism. (DH)

Weber, Klaus; Osborn, Mary

1985-01-01

244

On the digraph of a unitary matrix  

E-print Network

Abstract. Given a matrix M of size n, the digraph D on n vertices is said to be the digraph of M, when Mij ? = 0 if and only if (vi, vj) is an arc of D. We give a necessary condition, called strong quadrangularity, for a digraph to be the digraph of a unitary matrix. With the use of such a

Simone Severini

2003-01-01

245

Automatic Rees Matrix Semigroups over Categories  

Microsoft Academic Search

We consider the preservation of the properties of automaticity and prefix-automaticity in Rees matrix semigroups over semigroupoids\\u000a and small categories. Some of our results are new or improve upon existing results in the single-object case of Rees matrix\\u000a semigroups over semigroups.

Mark Kambites

2007-01-01

246

Implications of a rotating mass matrix  

Microsoft Academic Search

The fermion mass matrix, in addition to having eigenvalues (masses) which run, also changes its orientation (rotates) with changing energy scales. This means that its eigenstates at one scale will no longer be eigenstates at another scale, leading to effects where fermions of different flavors can ``transmute'' into one another. In this paper, the implications of a rotating mass matrix

José Bordes; Chan Hong-Mo; Tsou Sheung Tsun

2001-01-01

247

The Hat Matrix in Regression and ANOVA  

Microsoft Academic Search

In least-squares fitting it is important to understand the influence which a data y value will have on each fitted y value. A projection matrix known as the hat matrix contains this information and, together with the Studentized residuals, provides a means of identifying exceptional data points. This approach also simplifies the calculations involved in removing a data point, and

David C. Hoaglin; Roy E. Welsch

1978-01-01

248

RANK-SPARSITY INCOHERENCE FOR MATRIX DECOMPOSITION ...  

E-print Network

Jun 11, 2009 ... For a matrix M let ?(M) be the tangent space at M with respect to the variety of ... The quantity µ(M) being small for a matrix implies that the spectrum of any element ...... White represents a probability of success of 1, while black.

2009-06-11

249

A calcium fortified viral matrix protein  

PubMed Central

Summary In this issue of Structure, Leyrat and colleagues provide the first structural analysis of the HMPV matrix protein, a key regulator of viral assembly. Though structurally similar to other matrix proteins, two calcium binding sites suggest intriguing differences in regulation. PMID:24411575

Amarasinghe, Gaya K.; Dutch, Rebecca Ellis

2014-01-01

250

DETERMINANT MAXIMIZATION WITH LINEAR MATRIX INEQUALITY CONSTRAINTS  

Microsoft Academic Search

The problem of maximizing the determinant of a matrix subject to linear matrix inequalities (LMIs) arises in many fields, including computational geometry, statistics, system iden- tification, experiment design, and information and communication theory. It can also be considered as a generalization of the semidefinite programming problem. We give an overview of the applications of the determinant maximization problem, pointing out

LIEVEN VANDENBERGHE; STEPHEN BOYD; SHAO-PO WU

1996-01-01

251

HYGROTHERMAL AGING OF POLYIMIDE MATRIX COMPOSITE LAMINATES  

E-print Network

HYGROTHERMAL AGING OF POLYIMIDE MATRIX COMPOSITE LAMINATES John A. Nairn and Man-Hee Han Materials-0560, USA SUMMARY: Two polyimide-matrix systems were subjected to a series of hygrothermal aging experiments at various temperatures and relative humidities. For each aging condition, we measured the microcracking

Nairn, John A.

252

Matrix Management: An Organizational Alternative for Libraries.  

ERIC Educational Resources Information Center

Describes various organizational structures and models, presents matrix management as an alternative to traditional hierarchical structures, and suggests matrix management as an appropriate organizational alternative for academic libraries. Benefits that are discussed include increased flexibility, a higher level of professional independence, and…

Johnson, Peggy

1990-01-01

253

Matrix Metalloproteinase-9 and Autoimmune Diseases  

Microsoft Academic Search

Matrix metalloproteinases (also named matrixin or MMPs) are a major group of enzymes that regulate cell-matrix composition by using zinc for their proteolytic activities. They are essential for various normal biological processes such as embryonic development, morphogenesis, reproduction tissue resorption, and remodeling. Metalloproteinases also play a role in pathological processes including inflammation, arthritis, cardiovascular diseases, pulmonary diseases and cancer. Herein

Maya Ram; Yaniv Sherer; Yehuda Shoenfeld

2006-01-01

254

KS ring theoretic approach for matrix multiplication  

Microsoft Academic Search

Matrix multiplication is a very common operation performed in many real world applications. So much of research has been done in reducing the time complexity of multiplying two matrices by researchers like Strassen, Don Coppersmith, Shmuel Winograd etc. All mathematical software also rely upon the common matrix multiplication algorithm. But, if the matrices that has to be applied has some

S. S. Dharwez; B. Karpagam

2011-01-01

255

Weak matrix elements for CP violation.  

SciTech Connect

We present preliminary results of matrix elements of four fermion operators relevant to the determination of e and E ' / E using staggered fermions. To calculate the matrix elements relevant to CP violation in Kaon decays it is important to use a lattice formulation which preserves (some) chiral symmetry.

Lee, W. (Weonjong); Gupta, R. (Rajan); Christ, N.; Fleming, G. T.; Kilcup, G. (Gregory); Liu, G.; Mawhinney, R. (Robert); Sharpe, S. (Steven); Wu, L.; Bhattacharya, T. (Tanmoy)

2001-01-01

256

Advanced Integration Matrix Education Outreach  

NASA Technical Reports Server (NTRS)

The Advanced Integration Matrix (AIM) will design a ground-based test facility for developing revolutionary integrated systems for joint human-robotic missions in order to study and solve systems-level integration issues for exploration missions beyond Low Earth Orbit (LEO). This paper describes development plans for educational outreach activities related to technological and operational integration scenarios similar to the challenges that will be encountered through this project. The education outreach activities will provide hands-on, interactive exercises to allow students of all levels to experience design and operational challenges similar to what NASA deals with everyday in performing the integration of complex missions. These experiences will relate to and impact students everyday lives by demonstrating how their interests in science and engineering can develop into future careers, and reinforcing the concepts of teamwork and conflict resolution. Allowing students to experience and contribute to real-world development, research, and scientific studies of ground-based simulations for complex exploration missions will stimulate interest in the space program, and bring NASA's challenges to the student level. By enhancing existing educational programs and developing innovative activities and presentations, AIM will support NASA s endeavor to "inspire the next generation of explorers.. .as only NASA can."

Paul Heather L.

2004-01-01

257

TRASYS form factor matrix normalization  

NASA Technical Reports Server (NTRS)

A method has been developed for adjusting a TRASYS enclosure form factor matrix to unity. This approach is not limited to closed geometries, and in fact, it is primarily intended for use with open geometries. The purpose of this approach is to prevent optimistic form factors to space. In this method, nodal form factor sums are calculated within 0.05 of unity using TRASYS, although deviations as large as 0.10 may be acceptable, and then, a process is employed to distribute the difference amongst the nodes. A specific example has been analyzed with this method, and a comparison was performed with a standard approach for calculating radiation conductors. In this comparison, hot and cold case temperatures were determined. Exterior nodes exhibited temperature differences as large as 7 C and 3 C for the hot and cold cases, respectively when compared with the standard approach, while interior nodes demonstrated temperature differences from 0 C to 5 C. These results indicate that temperature predictions can be artificially biased if the form factor computation error is lumped into the individual form factors to space.

Tsuyuki, Glenn T.

1992-01-01

258

The Evolution of Extracellular Matrix  

PubMed Central

We present a perspective on the molecular evolution of the extracellular matrix (ECM) in metazoa that draws on research publications and data from sequenced genomes and expressed sequence tag libraries. ECM components do not function in isolation, and the biological ECM system or “adhesome” also depends on posttranslational processing enzymes, cell surface receptors, and extracellular proteases. We focus principally on the adhesome of internal tissues and discuss its origins at the dawn of the metazoa and the expansion of complexity that occurred in the chordate lineage. The analyses demonstrate very high conservation of a core adhesome that apparently evolved in a major wave of innovation in conjunction with the origin of metazoa. Integrin, CD36, and certain domains predate the metazoa, and some ECM-related proteins are identified in choanoflagellates as predicted sequences. Modern deuterostomes and vertebrates have many novelties and elaborations of ECM as a result of domain shuffling, domain innovations and gene family expansions. Knowledge of the evolution of metazoan ECM is important for understanding how it is built as a system, its roles in normal tissues and disease processes, and has relevance for tissue engineering, the development of artificial organs, and the goals of synthetic biology. PMID:21160071

Özbek, Suat; Balasubramanian, Prakash G.; Chiquet-Ehrismann, Ruth; Tucker, Richard P.

2010-01-01

259

Refined matrix models from BPS counting  

SciTech Connect

We construct a free fermion and matrix model representation of refined Bogomol'nyi-Prasad-Sommerfeld generating functions of D2 and D0 branes bound to a single D6 brane, in a class of toric manifolds without compact four-cycles. In appropriate limit we obtain a matrix model representation of refined topological string amplitudes. We consider a few explicit examples which include a matrix model for the refined resolved conifold, or equivalently five-dimensional U(1) gauge theory, as well as a matrix representation of the refined MacMahon function. Matrix models which we construct have ordinary unitary measure, while their potentials are modified to incorporate the effect of the refinement.

Sulkowski, Piotr [California Institute of Technology, Pasadena, California 91125 (United States)

2011-04-15

260

Thermoviscoplastic analysis of metal matrix composites  

SciTech Connect

Micromechanics-based thermoviscoplasticity theories based on over-stress are developed for metal matrix composites. Three micromechanics models, the vanishing fiber diameter model, the Mori-Tanaka method, and the bimodal model, are used in conjunction with the orthotropic thermoviscoplasticity theory based on overstress to study the thermomechanical behavior. Numerical experiments using the vanishing fiber diameter model and the orthotropic thermoviscoplasticity theory based on overstress were performed to study the effects of residual stresses, volume fraction, creep, thermal cycling, and ratchetting on the behavior of metal matrix composites. For the purpose of modeling the matrix-dominated low-cycle fatigue damage of metal matrix composites under multiaxial creep-fatigue interaction, an incremental multiaxial life prediction law for the metal matrix is proposed. This model consists of the three-dimensional, cyclic neutral thermoviscoplasticity theory based on overstress combined with a multiaxial damage accumulation law to compute the life time or cycles to crack initiation.

Yeh Nanming.

1991-01-01

261

Fiber-matrix interfaces in ceramic composites  

SciTech Connect

The mechanical properties of ceramic matrix composites (CMCs) are governed by the relationships between the matrix, the interface material, and the fibers. In non-oxide matrix systems compliant pyrolytic carbon and BN have been demonstrated to be effective interface materials, allowing for absorption of mismatch stresses between fiber and matrix and offering a poorly bonded interface for crack deflection. The resulting materials have demonstrated remarkable strain/damage tolerance together with high strength. Carbon or BN, however, suffer from oxidative loss in many service environments, and thus there is a major search for oxidation resistant alternatives. This paper reviews the issues related to developing a stable and effective interface material for non-oxide matrix CMCs.

Besmann, T.M.; Stinton, D.P.; Kupp, E.R. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.; Shanmugham, S.; Liaw, P.K. [Univ. of Tennessee, Knoxville, TN (United States). Materials Science and Engineering Dept.

1996-12-31

262

Simple parametrization of neutrino mixing matrix  

NASA Astrophysics Data System (ADS)

We propose simple forms of the neutrino mixing matrix in analogy with the Wolfenstein parametrization of the quark mixing matrix by adopting the smallest mixing angle ?13 as a measure of expansion parameters with the tribimaximal pattern as the base matrix. The triminimal parametrization technique is utilized to expand the mixing matrix under two schemes, i.e., the standard Chau-Keung scheme and the original Kobayashi-Maskawa scheme. The new parametrizations have their corresponding Wolfenstein-like parametrizations of the quark mixing matrix, and therefore they share the same intriguing features of the Wolfenstein parametrization. The newly introduced expansion parameters for neutrinos are connected to the Wolfenstein parameters for quarks via the quark-lepton complementarity.

Ma, Bo-Qiang

2013-01-01

263

SevenOperators, a Mathematica script for harmonic oscillator nuclear matrix elements arising in semileptonic electroweak interactions  

NASA Astrophysics Data System (ADS)

Semi-leptonic electroweak interactions in nuclei—such as ? decay, ? capture, charged- and neutral-current neutrino reactions, and electron scattering—are described by a set of multipole operators carrying definite parity and angular momentum, obtained by projection from the underlying nuclear charge and three-current operators. If these nuclear operators are approximated by their one-body forms and expanded in the nucleon velocity through order |p?|/M, where p? and M are the nucleon momentum and mass, a set of seven multipole operators is obtained. Nuclear structure calculations are often performed in a basis of Slater determinants formed from harmonic oscillator orbitals, a choice that allows translational invariance to be preserved. Harmonic-oscillator single-particle matrix elements of the multipole operators can be evaluated analytically and expressed in terms of finite polynomials in q, where q is the magnitude of the three-momentum transfer. While results for such matrix elements are available in tabular form, with certain restriction on quantum numbers, the task of determining the analytic form of a response function can still be quite tedious, requiring the folding of the tabulated matrix elements with the nuclear density matrix, and subsequent algebra to evaluate products of operators. Here we provide a Mathematica script for generating these matrix elements, which will allow users to carry out all such calculations by symbolic manipulation. This will eliminate the errors that may accompany hand calculations and speed the calculation of electroweak nuclear cross sections and rates. We illustrate the use of the new script by calculating the cross sections for charged- and neutral-current neutrino scattering in 12C. Program summaryProgram title: SevenOperators Catalogue identifier: AEAY_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEAY_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.: 2227 No. of bytes in distributed program, including test data, etc.: 19 382 Distribution format: tar.gz Programming language: Mathematica Computer: Any computer running Mathematica; tested on Mac OS X PowerPC (32-bit) running Mathematica 6.0.0 Operating system: Any running Mathematica RAM: Memory requirements determined by Mathematica; 512 MB or greater RAM and hard drive space of at least 3.0 GB recommended Classification: 17.16, 17.19 Nature of problem: Algebraic evaluation of harmonic oscillator nuclear matrix elements for the one-body multipole operators governing semi-leptonic weak interactions, such as charged- or neutral-current neutrino scattering off nuclei. Solution method: Mathematica evaluation of associated angular momentum algebra and spherical Bessel function radial integrals. Running time: Depends on the complexity of the one-body density matrix employed, but times of a few seconds are typical.

Haxton, Wick; Lunardini, Cecilia

2008-09-01

264

REACTIONS IN RARE GAS MATRICES MATRIX AND SITE EFFECTS  

E-print Network

, was to prevent them from reacting. The term matrix isolation, coined by Pimentel [Whittle 1954] impliesREACTIONS IN RARE GAS MATRICES ­ MATRIX AND SITE EFFECTS Y. Haas and U. Samuni Department in matrices ­ matrix and site effects 215 1·2 How ordered is a matrix? 216 1·4 Matrix structure ­ diffraction

Haas, Yehuda

265

Nonnegative Matrix Factorization Barbara Ball Atina Brooks Amy Langville  

E-print Network

-by-purchase matrix gene-by-DNA microarray matrix terrorist-by-action matrix SVD A = U VT = r i=1 iuivT i #12;7 of 30 gene-by-DNA microarray matrix terrorist-by-action matrix SVD A = U VT = r i=1 iuivT i Low Rank

Kunkle, Tom

266

The simple-discernibility matrix in rough sets  

NASA Astrophysics Data System (ADS)

There are some advantages to describe knowledge with discernibility matrix ,As for the discernibility matrix of decision tables, this paper finds that there exist that some redundant information of discernibility matrix. so this paper defines a new discernibility matrix ,which is named Simple Discernibility matrix .it has no redundant information and could reduce the number of comparisons of individuals ,and improve the efficiency.

Deng, Shaobo; Li, Min

2012-01-01

267

The simple-discernibility matrix in rough sets  

NASA Astrophysics Data System (ADS)

There are some advantages to describe knowledge with discernibility matrix ,As for the discernibility matrix of decision tables, this paper finds that there exist that some redundant information of discernibility matrix. so this paper defines a new discernibility matrix ,which is named Simple Discernibility matrix .it has no redundant information and could reduce the number of comparisons of individuals ,and improve the efficiency.

Deng, Shaobo; Li, Min

2011-12-01

268

Linear and nonlinear projective nonnegative matrix factorization.  

PubMed

A variant of nonnegative matrix factorization (NMF) which was proposed earlier is analyzed here. It is called projective nonnegative matrix factorization (PNMF). The new method approximately factorizes a projection matrix, minimizing the reconstruction error, into a positive low-rank matrix and its transpose. The dissimilarity between the original data matrix and its approximation can be measured by the Frobenius matrix norm or the modified Kullback-Leibler divergence. Both measures are minimized by multiplicative update rules, whose convergence is proven for the first time. Enforcing orthonormality to the basic objective is shown to lead to an even more efficient update rule, which is also readily extended to nonlinear cases. The formulation of the PNMF objective is shown to be connected to a variety of existing NMF methods and clustering approaches. In addition, the derivation using Lagrangian multipliers reveals the relation between reconstruction and sparseness. For kernel principal component analysis (PCA) with the binary constraint, useful in graph partitioning problems, the nonlinear kernel PNMF provides a good approximation which outperforms an existing discretization approach. Empirical study on three real-world databases shows that PNMF can achieve the best or close to the best in clustering. The proposed algorithm runs more efficiently than the compared NMF methods, especially for high-dimensional data. Moreover, contrary to the basic NMF, the trained projection matrix can be readily used for newly coming samples and demonstrates good generalization. PMID:20350841

Yang, Zhirong; Oja, Erkki

2010-05-01

269

[Modern polymers in matrix tablets technology].  

PubMed

Matrix tablets are the most popular method of oral drug administration, and polymeric materials have been used broadly in matrix formulations to modify and modulate drug release rate. The main goal of the system is to extend drug release profiles to maintain a constant in vivo plasma drug concentration and a consistent pharmacological effect. Polymeric matrix tablets offer a great potential as oral controlled drug delivery systems. Cellulose derivatives, like hydroxypropyl methylcellulose (HPMC) are often used as matrix formers. However, also other types of polymers can be used for this purpose including: Kollidon SR, acrylic acid polymers such as Eudragits and Carbopols. Nevertheless, polymers of natural origin like: carragens, chitosan and alginates widely used in the food and cosmetics industry are now coming to the fore of pharmaceutical research and are used in matrix tablets technology. Modern polymers allow to obtain matrix tablets by 3D printing, which enables to develop new formulation types. In this paper, the polymers used in matrix tablets technology and examples of their applications were described. PMID:25739125

Zimmer, ?ukasz; Kasperek, Regina; Poleszak, Ewa

2014-01-01

270

A new look at the nuclear matrix.  

PubMed

The concept of the nuclear matrix, a karyoskeletal structure that serves as a support for the genome and its activities, has stimulated many studies of the association of nuclear components and functions with this structure. However, certain experimental findings are not consistent with the existence of the nuclear matrix in vivo, including our inability to visualise a corresponding structure in intact cells, the demonstrated mobility in vivo of chromatin and messenger ribonucleoprotein particles, which are claimed to be bound to the nuclear matrix, the paradoxical extractability from nuclei in low ionic strength buffers of enzymes that are found in the 2 M NaCl-insoluble matrix, and the extractability, in conditions which reproduce the intranuclear milieu, of regions of DNA (matrix or scaffold attachment regions, MAR/SARs) postulated to be bound to the nuclear matrix in vivo. This review considers the nuclear matrix model in the light of sometimes overlooked evidence that each step in its isolation may cause nuclear components to bind to it by new liaisons that do not exist in vivo. This is illustrated by experiments where nuclear-targeted green fluorescent protein is found in the nuclear matrix, and raises the possibility that MAR/SARs actually bind to DNA-binding proteins or multiprotein complexes, including replicational, transcriptional and processing machinery, and topoisomerases that are incorporated into the nuclear matrix during its preparation. Considering that the nuclear lamina forms a rigid exoskeleton, the necessity for internal skeletal structures is raised; the major roles that macromolecular crowding, phase partitioning, and charge effects are likely to play in organisation of the intranuclear space may provide new models for the compartmentalisation of proteins and functions into different nuclear domains and of chromosomes into territories. PMID:10968250

Hancock, R

2000-07-01

271

Cardiac matrix: a clue for future therapy  

PubMed Central

Cardiac muscle is unique because it contracts ceaselessly throughout the life and is highly resistant to fatigue. The marvelous nature of the cardiac muscle is attributed to its matrix that maintains structural and functional integrity and provides ambient micro-environment required for mechanical, cellular and molecular activities in the heart. Cardiac matrix dictates the endothelium-myocyte (E-M) coupling and contractility of cardiomyocytes. The Matrix metalloproteinases (MMPs) and their tissue inhibitor of metalloproteinases (TIMPs) regulate matrix degradation that determines cardiac fibrosis and myocardial performance. We have shown that MMP-9 regulates differential expression of micro RNAs (miRNAs), calcium cycling and contractility of cardiomyocytes. The differential expression of miRNAs is associated with angiogenesis, hypertrophy and fibrosis in the heart. MMP-9, which is involved in the degradation of cardiac matrix and induction of fibrosis, is also implicated in inhibition of survival and differentiation of cardiac stem cells (CSC). Cardiac matrix is distinct because it renders mechanical properties and provides a framework essential for differentiation of cardiac progenitor cells (CPC) into specific lineage. Cardiac matrix regulates myocyte contractility by E-M coupling and calcium transients and also directs miRNAs required for precise regulation of continuous and synchronized beating of cardiomyocytes that is indispensible for survival. Alteration in the matrix homeostasis due to induction of MMPs, altered expression of specific miRNAs or impaired signaling for contractility of cardiomyocytes leads to catastrophic effects. This review describes the mechanisms by which cardiac matrix regulates myocardial performance and suggests future directions for the development of treatment strategies in cardiovascular diseases. PMID:24055000

Mishra, Paras Kumar; Givvimani, Srikanth; Chavali, Vishalakshi; Tyagi, Suresh C.

2014-01-01

272

An ESS maximum principle for matrix games.  

PubMed

Previous work has demonstrated that for games defined by differential or difference equations with a continuum of strategies, there exists a G-function, related to individual fitness, that must take on a maximum with respect to a virtual variable v whenever v is one of the vectors in the coalition of vectors which make up the evolutionarily stable strategy (ESS). This result, called the ESS maximum principle, is quite useful in determining candidates for an ESS. This principle is reformulated here, so that it may be conveniently applied to matrix games. In particular, we define a matrix game to be one in which fitness is expressed in terms of strategy frequencies and a matrix of expected payoffs. It is shown that the G-function in the matrix game setting must again take on a maximum value at all the strategies which make up the ESS coalition vector. The reformulated maximum principle is applicable to both bilinear and nonlinear matrix games. One advantage in employing this principle to solve the traditional bilinear matrix game is that the same G-function is used to find both pure and mixed strategy solutions by simply specifying an appropriate strategy space. Furthermore we show how the theory may be used to solve matrix games which are not in the usual bilinear form. We examine in detail two nonlinear matrix games: the game between relatives and the sex ratio game. In both of these games an ESS solution is determined. These examples not only illustrate the usefulness of this approach to finding solutions to an expanded class of matrix games, but aids in understanding the nature of the ESS as well. PMID:11120647

Vincent, T L; Cressman, R

2000-11-01

273

Transitions to the ground state in synchrotron radiation: Numerical calculations derived from exact matrix elements  

Microsoft Academic Search

The problem of an electron immersed in a uniform magnetic field is viewed from the framework of the relativistic Dirac theory. Because of the simple mathematical structure of the ground state it is possible to evaluate the first-order transition rates to the ground state lambdan0 exactly. Explicit results for lambdan0 are given in analytical, tabular, and graphical form for a

D. White

1974-01-01

274

Concept order parameter for random matrix ensemble  

NASA Astrophysics Data System (ADS)

For the sparse random matrix ensemble exhibiting transitions from chaotic properties to integrable ones while the control parameter is varying the order parameter is introduced. The proposed concept is based on a division of the random matrix ensemble into equivalence classes of equal matrix ranks. The order parameter is proportional to the number of equivalence classes and is expressed by the average rank of random matrices. For practical purposes it is approximated by the jump of the cumulative distribution function at energy E = 0.

Sokalski, Krzysztof

1997-02-01

275

Recent Developments on the CKM Matrix  

E-print Network

In Standard Model, CP violation arises from an irreducible complex phase in the quark mixing matrix, now under the name Cabibbo-Kobayashi-Maskawa matrix. This description has shown remarkably overall agreement with various experimental measurements. In this review, we discuss recent experimental data and theoretical developments on three quantities of CKM matrix that are most uncertain: the $V_{ub}$, including its magnitude and the phase $\\gamma$ in standard parametrization, and the $B_s-\\bar B_s$ mixing phase $\\beta_s$.

Wei Wang

2014-08-05

276

Matrix Differential Calculus {DRAFTVersion 1.1}  

E-print Network

is a symmetric matrix then: |X| X = Xii if i = j 2Xij if i = j , (2.1) where Xij is the (i, j)-th co-factor of X that |X| X is a matrix whose (i, j)-th entry is given by |X| xij . We know from elementary matrix theory that: |X| = n j=1 xijXij = n i=1 xijXij, (2.2) where Xij is the (i, j)-th co-factor of X. Hence

Sra, Suvrit

277

Anderson transition for Google matrix eigenstates  

E-print Network

We introduce a number of random matrix models describing the Google matrix G of directed networks. The properties of their spectra and eigenstates are analyzed by numerical matrix diagonalization. We show that for certain models it is possible to have an algebraic decay of PageRank vector with the exponent similar to real directed networks. At the same time the spectrum has no spectral gap and a broad distribution of eigenvalues in the complex plain. The eigenstates of G are characterized by the Anderson transition from localized to delocalized states and a mobility edge curve in the complex plane of eigenvalues.

Zhirov, O V

2015-01-01

278

Three-Algebra Bfss Matrix Theory  

NASA Astrophysics Data System (ADS)

We extend the BFSS matrix theory by means of Lie 3-algebra. The extended model possesses the same supersymmetry as the original BFSS matrix theory, and thus as the infinite momentum frame limit of M-theory. We study dynamics of the model by choosing the minimal Lie 3-algebra that includes u(N) algebra. We can solve a constraint in the minimal model and obtain two phases. In one phase, the model reduces to the original matrix model. In another phase, it reduces to a simple supersymmetric model.

Sato, Matsuo

2013-11-01

279

Visual Matrix Clustering of Social Networks  

SciTech Connect

The prevailing choices to graphically represent a social network in today’s literature are a node-link graph layout and an adjacency matrix. Both visualization techniques have unique strengths and weaknesses when applied to different domain applications. In this article, we focus our discussion on adjacency matrix and how to turn the matrix-based visualization technique from merely showing pairwise associations among network actors (or graph nodes) to depicting clusters of a social network. We also use node-link layouts to supplement the discussion.

Wong, Pak C.; Mackey, Patrick S.; Foote, Harlan P.; May, Richard A.

2013-07-01

280

A transilient matrix for moist convection  

SciTech Connect

A method is introduced for diagnosing a transilient matrix for moist convection. This transilient matrix quantifies the nonlocal transport of air by convective eddies: for every height z, it gives the distribution of starting heights z{prime} for the eddies that arrive at z. In a cloud-resolving simulation of deep convection, the transilient matrix shows that two-thirds of the subcloud air convecting into the free troposphere originates from within 100 m of the surface. This finding clarifies which initial height to use when calculating convective available potential energy from soundings of the tropical troposphere.

Romps, D.; Kuang, Z.

2011-08-15

281

Active Matrix OLED Test Report  

NASA Technical Reports Server (NTRS)

This report focuses on the limited environmental testing of the AMOLED display performed as an engineering evaluation by The NASA Johnson Space Center (JSC)-specifically. EMI. Thermal Vac, and radiation tests. The AMOLED display is an active-matrix Organic Light Emitting Diode (OLED) technology. The testing provided an initial understanding of the technology and its suitability for space applications. Relative to light emitting diode (LED) displays or liquid crystal displays (LCDs), AMOLED displays provide a superior viewing experience even though they are much lighter and smaller, produce higher contrast ratio and richer colors, and require less power to operate than LCDs. However, AMOLED technology has not been demonstrated in a space environment. Therefore, some risks with the technology must be addressed before they can be seriously considered for human spaceflight. The environmental tests provided preliminary performance data on the ability of the display technology to handle some of the simulated induced space/spacecraft environments that an AMOLED display will see during a spacecraft certification test program. This engineering evaluation is part of a Space Act Agreement (SM) between The NASA/JSC and Honeywell International (HI) as a collaborative effort to evaluate the potential use of AMOLED technology for future human spaceflight missions- both government-led and commercial. Under this SM, HI is responsible for doing optical performance evaluation, as well as temperature and touch screen studies. The NASA/JSC is responsible for performing environmental testing comprised of EMI, Thermal Vac, and radiation tests. Additionally, as part of the testing, limited optical data was acquired to assess performance as the display was subjected to the induced environments. The NASA will benefit from this engineering evaluation by understanding AMOLED suitability for future use in space as well as becoming a smarter buyer (or developer) of the technology. HI benefits from the environmental testing results by understanding its performance limitations/shortcomings to improve subsequent generations of AMOLED technology. Note that the AMOLED used in this test was not deSigned for the space environment but rather for commercial/industrial terrestrial applications.

Salazar, George

2013-01-01

282

The phase transition of matrix recovery from Gaussian measurements matches the minimax MSE of matrix denoising  

PubMed Central

Let be an unknown M by N matrix. In matrix recovery, one takes linear measurements of , where and each is an M by N matrix. A popular approach for matrix recovery is nuclear norm minimization (NNM): solving the convex optimization problem for all , where denotes the nuclear norm, namely, the sum of singular values. Empirical work reveals a phase transition curve, stated in terms of the undersampling fraction , rank fraction , and aspect ratio . Specifically when the measurement matrices Ai have independent standard Gaussian random entries, a curve exists such that, if , NNM typically succeeds for large M,N, whereas if , it typically fails. An apparently quite different problem is matrix denoising in Gaussian noise, in which an unknown M by N matrix is to be estimated based on direct noisy measurements , where the matrix Z has independent and identically distributed Gaussian entries. A popular matrix denoising scheme solves the unconstrained optimization problem . When optimally tuned, this scheme achieves the asymptotic minimax mean-squared error , where . We report extensive experiments showing that the phase transition in the first problem, matrix recovery from Gaussian measurements, coincides with the minimax risk curve in the second problem, matrix denoising in Gaussian noise: , for any rank fraction (at each common aspect ratio ?). Our experiments considered matrices belonging to two constraint classes: real M by N matrices, of various ranks and aspect ratios, and real symmetric positive-semidefinite N by N matrices, of various ranks. PMID:23650360

Donoho, David L.; Gavish, Matan; Montanari, Andrea

2013-01-01

283

Matrix metalloproteinase-7 and matrix metalloproteinase-9 in pediatric multiple sclerosis.  

PubMed

Matrix metalloproteinases and their tissue inhibitors play a key role in the pathogenesis of adult-onset multiple sclerosis, and were suggested as biomarkers of response to interferon-?, an established treatment in multiple sclerosis. However, data regarding pediatric population are scarce. We determined serum levels of matrix metalloproteinase-7, matrix metalloproteinase-9, and tissue inhibitor of matrix metalloproteinase-1 in children, and evaluated effects of interferon-? therapy on these measures. Serum samples from 14 children with relapsing, remitting multiple sclerosis at baseline and at month 12, and from 15 controls, were collected. Interferon-? treatment was initiated in eight patients. Mean serum matrix metalloproteinase-9 levels and matrix metalloproteinase-9/tissue inhibitor of matrix metalloproteinase-1 ratio were higher in patients compared with controls, and were reduced significantly in treated patients at month 12, but did not change in untreated patients. Mean matrix metalloproteinase-7 levels were lower in patients compared with controls, and increased significantly in the treated group, but did not change significantly in the untreated group. In pediatric multiple sclerosis, a shift in matrix metalloproteinase-9/tissue inhibitor of matrix metalloproteinase-1 balance toward proteolytic activity is evident, and interferon-? therapy demonstrates a beneficial effect on this disturbed balance. PMID:22883281

Y?lmaz, Ünsal; Unsal, Y?lmaz; Gücüyener, K?v?lc?m; K?v?lc?m, Gücüyener; Atak, Ay?egül; Ay?egül, Atak; Aral, Arzu; Arzu, Aral; Gürka?, Esra; Esra, Gürka?; Demir, Ercan; Ercan, Demir; Serdaro?lu, Ay?e; Ay?e, Serdaro?lu

2012-09-01

284

Matrix isolation spectroscopy of propylbenzene conformers and trapping sites  

E-print Network

Matrix isolation spectroscopy of propylbenzene conformers and trapping sites Shlomit Dvir data. In this paper we report the matrix isolation UV and laser induced fluorescence spectra 2001 Ultraviolet absorption and emission spectra of propylbenzene in an argon matrix are presented

Haas, Yehuda

285

Simulation of bilinear flow in single matrix block drainage  

E-print Network

with a hydraulic fracture analytical solution. Two different production scenarios, constant pwf and constant rate, are assigned to a tight gas well in matrix block drainage. Matrix block drainage has two distinct permeabilities; a low permeability matrix...

Branajaya, Romi Triaji

2005-02-17

286

Dynamic Matrix Control of nonlinear processes  

SciTech Connect

Dynamic Matrix Control (DMC) is a digital-control algorithm developed by Shell Oil Company in the late 1960's. It implements a least squares optimal controller on linear systems and has conventional feedback and feedforward control ability. It also provides a way to achieve predictive and optimal control. An extension, Universal Dynamic Matrix Control (UDMC), incorporates Successive Quadratic Programming (SQP) to handle nonlinear process with inequality constraint. In this work, the theoretical aspects of implementation of UDMC on a bioreactor process are described. The error response of UDMC is investigated and the feasibility of using UDMC for the bioreactor process on microcomputer is also discussed. The most time-consuming aspect of the nonlinear control algorithm is updating the dynamic matrix or Jacobian every sample interval. This work also describes an efficient computation method for the Jacobian matrix based on the sensitivity equations for UDMC.

Lin, H.Y.

1987-01-01

287

The evolution of metazoan extracellular matrix  

E-print Network

The modular domain structure of extracellular matrix (ECM) proteins and their genes has allowed extensive exon/domain shuffling during evolution to generate hundreds of ECM proteins. Many of these arose early during metazoan ...

Hynes, Richard O.

288

Breast Multiple Primary and Histology Rules Matrix  

Cancer.gov

Breast Multiple Primary Rules – Matrix C500 – C509 (Excludes lymphoma and leukemia M9590 – 9989 and Kaposi sarcoma M9140) * Prepare one abstract. Use the histology coding rules to assign the appropriate histology code. ** Prepare two or more abstracts.

289

Role of MEPE in chondrocyte matrix mineralisation   

E-print Network

Matrix Extracellular Phosphoglycoprotein (MEPE) is a member of a family of proteins called small integrin-binding ligand, N-linked glycoproteins (SIBLINGs) which play key roles in biomineralisation. Altered MEPE expression ...

Staines, Katherine Ann

2012-11-30

290

Optimal matrix approximants in structural identification  

NASA Technical Reports Server (NTRS)

Problems of model correlation and system identification are central in the design, analysis, and control of large space structures. Of the numerous methods that have been proposed, many are based on finding minimal adjustments to a model matrix sufficient to introduce some desirable quality into that matrix. In this work, several of these methods are reviewed, placed in a modern framework, and linked to other previously known ideas in computational linear algebra and optimization. This new framework provides a point of departure for a number of new methods which are introduced here. Significant among these is a method for stiffness matrix adjustment which preserves the sparsity pattern of an original matrix, requires comparatively modest computational resources, and allows robust handling of noisy modal data. Numerical examples are included to illustrate the methods presented herein.

Beattie, C. A.; Smith, S. W.

1992-01-01

291

Integrated optic vector-matrix multiplier  

DOEpatents

A vector-matrix multiplier is disclosed which uses N different wavelengths of light that are modulated with amplitudes representing elements of an N.times.1 vector and combined to form an input wavelength-division multiplexed (WDM) light stream. The input WDM light stream is split into N streamlets from which each wavelength of the light is individually coupled out and modulated for a second time using an input signal representing elements of an M.times.N matrix, and is then coupled into an output waveguide for each streamlet to form an output WDM light stream which is detected to generate a product of the vector and matrix. The vector-matrix multiplier can be formed as an integrated optical circuit using either waveguide amplitude modulators or ring resonator amplitude modulators.

Watts, Michael R. (Albuquerque, NM)

2011-09-27

292

Plato's Fire and the Neutrino Mass Matrix  

E-print Network

With the accumulation of many years of solar and atmospheric neutrino oscillation data, the approximate form of the 3 X 3 neutrino mixing matrix is now known. The theoretical challenge is to understand where this mixing matrix comes from. Recently, a remarkable fact was discovered that for a specific pattern of the neutrino mass matrix at a high scale, any flavor-changing radiative correction will automatically lead to the desired mixing matrix. It was also discovered that the required specific pattern at the high scale can be maintained by the non-Abelian discrete symmetry A_4 which is also the symmetry group of the regular tetrahedron, one of five perfect geometric solids known to Plato who associated it with the element ``fire''. I discuss this recent development and add to it a new and very simple mechanism for the implementation of the flavor-changing radiative correction.

Ernest Ma

2002-11-25

293

On the digraph of a unitary matrix  

E-print Network

Given a matrix M of size n, a digraph D on n vertices is said to be the digraph of M, when M_{ij} is different from 0 if and only if (v_{i},v_{j}) is an arc of D. We give a necessary condition, called strong quadrangularity, for a digraph to be the digraph of a unitary matrix. With the use of such a condition, we show that a line digraph, LD, is the digraph of a unitary matrix if and only if D is Eulerian. It follows that, if D is strongly connected and LD is the digraph of a unitary matrix then LD is Hamiltonian. We conclude with some elementary observations. Among the motivations of this paper are coined quantum random walks, and, more generally, discrete quantum evolution on digraphs.

Simone Severini

2003-07-17

294

Proton decay matrix elements from lattice QCD   

E-print Network

We present results for the matrix elements relevant for proton decay in Grand Unified Theories (GUTs), using two methods. In the indirect method, we rely on an effective field theory description of proton decay, where ...

Cooney, Paul

2010-01-01

295

The Jones Matrix of a birefringent plate  

E-print Network

. We work in the PS polarization system (polarization parallel and perpendicular to the plane of incidence), and the boundary conditions of refraction are satisfied when we apply Fresnel's equations. The theory for the Jones Matrix is in agreement...

Wan, Xiaoke

1999-01-01

296

Graded Differential Geometry of Graded Matrix Algebras  

E-print Network

We study the graded derivation-based noncommutative differential geometry of the $Z_2$-graded algebra ${\\bf M}(n| m)$ of complex $(n+m)\\times(n+m)$-matrices with the ``usual block matrix grading'' (for $n\

Harald Grosse; Gert Reiter

1999-05-21

297

Matrix Revolutions, The Origin of Quantum Variables  

E-print Network

An informal guide to the history of Heisenberg's matrix mechanics. It is designed for mathematicians with only a minimal background in either physics or geometry, and it is based upon Heisenberg's original arguments.

Edward G. Effros

2004-02-05

298

Simplex Ceramic Matrix Composite Turbine Blisk Testing  

NASA Technical Reports Server (NTRS)

The purpose of this presentation is to discuss the testing and demonstration of the Ceramic Matrix Composite Turbine Blisk. Also discussed are material damping, fatigue life, damage to trailing edges, performance, unsteady blade loading, and stress.

Mash, Matt; McConnaughey, Helen V. (Technical Monitor)

2001-01-01

299

The Extracellular Matrix: Not Just Pretty Fibrils  

E-print Network

The extracellular matrix (ECM) and ECM proteins are important in phenomena as diverse as developmental patterning, stem cell niches, cancer, and genetic diseases. The ECM has many effects beyond providing structural support. ...

Hynes, Richard O.

300

Chondrule-matrix relationships in chondritic meteorites  

NASA Technical Reports Server (NTRS)

The relationship between chondrules and matrix (fine grained material with a grain size less than 5 micrometers) in chondritic meteorites has been the subject of considerable controversy and no consensus currently exists. The coexistence of these two components in meteorites with bulk compositions that deviate only slightly from CI abundances suggests that cosmochemically their origins are closely linked. Any consideration of the relationship between chondrules and matrix hinges to a large degree on the origin of matrix. The entire spectrum of models exists from matrix as a nebular product to derivation entirely from chondrules. Early models of solar nebular evolution viewed chondrites as a two-component mixture of high- and low-temperature condensates. However, this model has been challenged by the recognition that the nebula was probably not uniformly vaporized.

Brearley, A. J.

1994-01-01

301

ESS Matrix: Biggest Ideas of Science  

NSDL National Science Digital Library

For the course development purposes, we can order and describe classes of system interactions possible using a design matrix that identifies case examples that illustrate the relationships and interactions between ...

302

EUCLIDEAN DISTANCE MATRIX COMPLETION PROBLEMS June ...  

E-print Network

Jun 6, 2010 ... unspecified entries to make A a Euclidean distance matrix. We survey three ..... For real problems such as protein structure ...... tein structure from distance geometry constraints obtained by nuclear magnetic resonance,. Prog.

2010-06-06

303

Comix, a new matrix element generator  

E-print Network

We present a new tree-level matrix element generator, based on the colour dressed Berends-Giele recursive relations. We discuss two new algorithms for phase space integration, dedicated to be used with large multiplicities and colour sampling.

Tanju Gleisberg; Stefan Hoeche

2008-11-24

304

Comix, a new matrix element generator  

NASA Astrophysics Data System (ADS)

We present a new tree-level matrix element generator, based on the colour dressed Berends-Giele recursive relations. We discuss two new algorithms for phase space integration, dedicated to be used with large multiplicities and colour sampling.

Gleisberg, Tanju; Höche, Stefan

2008-12-01

305

Comix, a New Matrix Element Generator  

SciTech Connect

We present a new tree-level matrix element generator, based on the color dressed Berends-Giele recursive relations. We discuss two new algorithms for phase space integration, dedicated to be used with large multiplicities and color sampling.

Gleisberg, Tanju; /SLAC; Hoche, Stefan; /Durham U., IPPP

2008-09-03

306

Matrix models of 2d gravity  

SciTech Connect

These are introductory lectures for a general audience that give an overview of the subject of matrix models and their application to random surfaces, 2d gravity, and string theory. They are intentionally 1.5 years out of date.

Ginsparg, P.

1991-12-31

307

Matrix models of 2d gravity  

SciTech Connect

These are introductory lectures for a general audience that give an overview of the subject of matrix models and their application to random surfaces, 2d gravity, and string theory. They are intentionally 1.5 years out of date.

Ginsparg, P.

1991-01-01

308

Micromechanical Modeling of Woven Metal Matrix Composites  

NASA Technical Reports Server (NTRS)

This report presents the results of an extensive micromechanical modeling effort for woven metal matrix composites. The model is employed to predict the mechanical response of 8-harness (8H) satin weave carbon/copper (C/Cu) composites. Experimental mechanical results for this novel high thermal conductivity material were recently reported by Bednarcyk et al. along with preliminary model results. The micromechanics model developed herein is based on an embedded approach. A micromechanics model for the local (micro-scale) behavior of the woven composite, the original method of cells (Aboudi), is embedded in a global (macro-scale) micromechanics model (the three-dimensional generalized method of cells (GMC-3D) (Aboudi). This approach allows representation of true repeating unit cells for woven metal matrix composites via GMC-3D, and representation of local effects, such as matrix plasticity, yarn porosity, and imperfect fiber-matrix bonding. In addition, the equations of GMC-3D were reformulated to significantly reduce the number of unknown quantities that characterize the deformation fields at the microlevel in order to make possible the analysis of actual microstructures of woven composites. The resulting micromechanical model (WCGMC) provides an intermediate level of geometric representation, versatility, and computational efficiency with respect to previous analytical and numerical models for woven composites, but surpasses all previous modeling work by allowing the mechanical response of a woven metal matrix composite, with an elastoplastic matrix, to be examined for the first time. WCGMC is employed to examine the effects of composite microstructure, porosity, residual stresses, and imperfect fiber-matrix bonding on the predicted mechanical response of 8H satin C/Cu. The previously reported experimental results are summarized, and the model predictions are compared to monotonic and cyclic tensile and shear test data. By considering appropriate levels of porosity, residual stresses, and imperfect fiber-matrix debonding, reasonably good qualitative and quantitative correlation is achieved between model and experiment.

Bednarcyk, Brett A.; Pindera, Marek-Jerzy

1997-01-01

309

Nanophosphor composite scintillator with a liquid matrix  

DOEpatents

An improved nanophosphor scintillator liquid comprises nanophosphor particles in a liquid matrix. The nanophosphor particles are optionally surface modified with an organic ligand. The surface modified nanophosphor particle is essentially surface charge neutral, thereby preventing agglomeration of the nanophosphor particles during dispersion in a liquid scintillator matrix. The improved nanophosphor scintillator liquid may be used in any conventional liquid scintillator application, including in a radiation detector.

McKigney, Edward Allen (Los Alamos, NM); Burrell, Anthony Keiran (Los Alamos, NM); Bennett, Bryan L. (Los Alamos, NM); Cooke, David Wayne (Santa Fe, NM); Ott, Kevin Curtis (Los Alamos, NM); Bacrania, Minesh Kantilal (Los Alamos, NM); Del Sesto, Rico Emilio (Los Alamos, NM); Gilbertson, Robert David (Los Alamos, NM); Muenchausen, Ross Edward (Los Alamos, NM); McCleskey, Thomas Mark (Los Alamos, NM)

2010-03-16

310

Automatic Performance Tuning of Sparse Matrix Kernels  

E-print Network

) ­ Diagonals, bands (up to 2.2x) ­ Splitting for variable block structure (1.3x--1.7x) ­ Reordering to create · Approximate x by power method: x = Akx0 ­ In practice, k 25 #12;Portion of the Google Matrix: A Snapshot #12 of the Google matrix ­ What optimizations are likely to pay-off? ­ Preliminary experiments: 2x speedups possible

California at Berkeley, University of

311

Another Conjecture about M(atrix) Theory  

Microsoft Academic Search

The current understanding of M(atrix) theory is that in the large N limit certain supersymmetric Yang Mills theories become equivalent to M-theory in the infinite momentum frame. In this paper the conjecture is put forward that the equivalence between M and M(atrix) theory is not limited to the large N limit but is valid for finite N. It is argued

Leonard Susskind

1997-01-01

312

Matrix String Theory on pp-waves  

E-print Network

After a brief review on Matrix String Theory on flat backgrounds, we formulate matrix string models on different pp-wave backgrounds. This will be done both in the case of constant and variable RR background flux for certain exact string geometries. We exhibit the non--perturbative representation of string interaction and show how the eigenvalue tunneling drives the WKB expansion to give the usual perturbative string interaction also in supersymmetric pp-wave background cases.

G. Bonelli

2002-10-22

313

Fuel cell with electrolyte matrix assembly  

DOEpatents

This invention is directed to a fuel cell employing a substantially immobilized electrolyte imbedded therein and having a laminated matrix assembly disposed between the electrodes of the cell for holding and distributing the electrolyte. The matrix assembly comprises a non-conducting fibrous material such as silicon carbide whiskers having a relatively large void-fraction and a layer of material having a relatively small void-fraction.

Kaufman, Arthur (West Orange, NJ); Pudick, Sheldon (Sayreville, NJ); Wang, Chiu L. (Edison, NJ)

1988-01-01

314

Email Surveillance Using Nonnegative Matrix Factorization  

Microsoft Academic Search

In this study, we apply a non-negative matrix factorization approach for the extraction and detection of concepts or topics\\u000a from electronic mail messages. For the publicly released Enron electronic mail collection, we encode sparse term-by-message\\u000a matrices and use a low rank non-negative matrix factorization algorithm to preserve natural data non-negativity and avoid\\u000a subtractive basis vector and encoding interactions present in

Michael W. Berry; Murray Browne

2005-01-01

315

Fibre-Matrix Interaction in Soft Tissue  

SciTech Connect

Although the mechanical behaviour of soft tissue has been extensively studied, the interaction between the collagen fibres and the ground matrix has not been well understood and is therefore ignored by most constitutive models of soft tissue. In this paper, the human annulus fibrosus is used as an example and the potential fibre-matrix interaction is identified by careful investigation of the experimental results of biaxial and uniaxial testing of the human annulus fibrosus. First, the uniaxial testing result of the HAF along the axial direction is analysed and it is shown that the mechanical behaviour of the ground matrix can be well simulated by the incompressible neo-Hookean model when the collagen fibres are all under contraction. If the collagen fibres are stretched, the response of the ground matrix can still be described by the incompressible neo-Hookean model, but the effective stiffness of the matrix depends on the fibre stretch ratio. This stiffness can be more than 10 times larger than the one obtained with collagen fibres under contraction. This phenomenon can only be explained by the fibre-matrix interaction. Furthermore, we find that the physical interpretation of this interaction includes the inhomogeneity of the soft tissue and the fibre orientation dispersion. The dependence of the tangent stiffness of the matrix on the first invariant of the deformation tensor can also be explained by the fibre orientation dispersion. The significant effect of the fibre-matrix interaction strain energy on mechanical behaviour of the soft tissue is also illustrated by comparing some simulation results.

Guo, Zaoyang [Departments of Civil and Mechanical Engineering, University of Glasgow Glasgow G12 8LT (United Kingdom)

2010-05-21

316

Numerical analysis of a quadratic matrix equation  

Microsoft Academic Search

The quadratic matrix equation AX2+BX +C = 0 in n \\\\Theta n matrices arises inapplications and is of intrinsic interest as one of the simplest nonlinear matrix equations.We give a complete characterization of solutions in terms of the generalizedSchur decomposition and describe and compare various numerical solution techniques.In particular, we give a thorough treatment of functional iteration methodsbased on Bernoulli's

NICHOLAS J. HIGHAM; HYUN-MIN KIM

1999-01-01

317

M-Theory of Matrix Models  

E-print Network

Small M-theories unify various models of a given family in the same way as the M-theory unifies a variety of superstring models. We consider this idea in application to the family of eigenvalue matrix models: their M-theory unifies various branches of Hermitean matrix model (including Dijkgraaf-Vafa partition functions) with Kontsevich tau-function. Moreover, the corresponding duality relations look like direct analogues of instanton and meron decompositions, familiar from Yang-Mills theory.

A. Alexandrov; A. Mironov; A. Morozov

2006-05-17

318

Sparsity: Optimization Framework for Sparse Matrix Kernels  

Microsoft Academic Search

Sparse matrix-vector multiplication is an important computational kernel that performs poorly on most modern processors due to a low compute-to-memory ratio and irregular memory access patterns. Opti- mization is dicult because of the complexity of cache-based memory systems and because performance is highly dependent on the nonzero structure of the matrix. The Sparsity system is designed to address these problems

Im Eun-jin; Katherine A. Yelick; Richard W. Vuduc

2004-01-01

319

Integrable couplings and matrix loop algebras  

NASA Astrophysics Data System (ADS)

We will discuss how to generate integrable couplings from zero curvature equations associated with matrix spectral problems. The key elements are matrix loop algebras consisting of block matrices with blocks of the same size or different sizes. Hamiltonian structures are furnished by applying the variational identity defined over semi-direct sums of Lie algebras. Illustrative examples include integrable couplings of the AKNS hierarchy by using the irreducible representations V2 and V3 of the special linear Lie algebra sl(2,R).

Ma, Wen-Xiu

2013-10-01

320

Granular Fe in a metallic matrix  

NASA Astrophysics Data System (ADS)

Ultrafine Fe particles with coercivities in excess of 500 Oe have been obtained by rapid annealing of sputtered metastable FexCu1-x alloys. The enhanced magnetic properties of these phase-separated materials are typical of single-domain Fe grains, and can be controlled by the annealing temperature. The Cu matrix, however, is highly conducting, unlike conventional granular materials where the matrix is generally insulating. The evolution of the magnetic properties and microstructure during annealing are described.

Childress, J. R.; Chien, C. L.; Nathan, M.

1990-01-01

321

Semiclassical form factor of matrix element fluctuations  

E-print Network

We analyze within a semiclassical approximation the form factor for the fluctuations of quantum matrix elements around their classical average. We find two contributions: one is proportional to the form factor for the density of states, with an amplitude determined by the squared average of the matrix elements. The other is constant and related to the fluctuations of finite time classical trajectory segments around the phase space average. The results are illustrated for an observable in the quadratic Zeeman effect.

Bruno Eckhardt; Joerg Main

1995-08-17

322

Novel butler matrix using CPW multilayer technology  

Microsoft Academic Search

In this paper, a novel 4 times 4 two-layer Butler matrix based on a broad-band two-layer slot-coupled directional coupler is presented and implemented at 5.8 GHz using coplanar waveguide technology. With the slot-coupled directional coupler, the proposed matrix was designed without using any crossovers as used in conventional Butler matrices, which leads to significant size reduction and loss minimization. To

Mourad Nedil; Tayeb A. Denidni; Larbi Talbi

2006-01-01

323

Topological String Correlators from Matrix Models  

E-print Network

We discuss how to compute connected matrix model correlators for operators related to the gravitational descendants of the puncture operator, for the topological A model on P^1. The relevant correlators are determined by recursion relations that follow from a systematic 1/N expansion of well chosen Schwinger-Dyson equations. Our results provide further compelling evidence for Gopakumar's proposed "simplest gauge string duality" between the Gaussian matrix model and the topological A model on P^1.

Robert de Mello Koch; Lwazi Nkumane

2015-02-07

324

Heterotic matrix string theory and Riemann surfaces  

Microsoft Academic Search

We extend the results found for Matrix String Theory to Heterotic Matrix String Theory, i.e. to a 2d O(N) SYM theory with chiral (anomaly free) matter and N=(8,0) supersymmetry. We write down the instanton equations for this theory and solve them explicitly. The solutions are characterized by branched coverings of the basis cylinder, i.e. by compact Riemann surfaces with punctures.

G. Bonelli; F. Nesti; A. Tomasiello

1999-01-01

325

CUR matrix decompositions for improved data analysis  

PubMed Central

Principal components analysis and, more generally, the Singular Value Decomposition are fundamental data analysis tools that express a data matrix in terms of a sequence of orthogonal or uncorrelated vectors of decreasing importance. Unfortunately, being linear combinations of up to all the data points, these vectors are notoriously difficult to interpret in terms of the data and processes generating the data. In this article, we develop CUR matrix decompositions for improved data analysis. CUR decompositions are low-rank matrix decompositions that are explicitly expressed in terms of a small number of actual columns and/or actual rows of the data matrix. Because they are constructed from actual data elements, CUR decompositions are interpretable by practitioners of the field from which the data are drawn (to the extent that the original data are). We present an algorithm that preferentially chooses columns and rows that exhibit high “statistical leverage” and, thus, in a very precise statistical sense, exert a disproportionately large “influence” on the best low-rank fit of the data matrix. By selecting columns and rows in this manner, we obtain improved relative-error and constant-factor approximation guarantees in worst-case analysis, as opposed to the much coarser additive-error guarantees of prior work. In addition, since the construction involves computing quantities with a natural and widely studied statistical interpretation, we can leverage ideas from diagnostic regression analysis to employ these matrix decompositions for exploratory data analysis. PMID:19139392

Mahoney, Michael W.; Drineas, Petros

2009-01-01

326

Matrix method for acoustic levitation simulation.  

PubMed

A matrix method is presented for simulating acoustic levitators. A typical acoustic levitator consists of an ultrasonic transducer and a reflector. The matrix method is used to determine the potential for acoustic radiation force that acts on a small sphere in the standing wave field produced by the levitator. The method is based on the Rayleigh integral and it takes into account the multiple reflections that occur between the transducer and the reflector. The potential for acoustic radiation force obtained by the matrix method is validated by comparing the matrix method results with those obtained by the finite element method when using an axisymmetric model of a single-axis acoustic levitator. After validation, the method is applied in the simulation of a noncontact manipulation system consisting of two 37.9-kHz Langevin-type transducers and a plane reflector. The manipulation system allows control of the horizontal position of a small levitated sphere from -6 mm to 6 mm, which is done by changing the phase difference between the two transducers. The horizontal position of the sphere predicted by the matrix method agrees with the horizontal positions measured experimentally with a charge-coupled device camera. The main advantage of the matrix method is that it allows simulation of non-symmetric acoustic levitators without requiring much computational effort. PMID:21859587

Andrade, Marco A B; Perez, Nicolas; Buiochi, Flavio; Adamowski, Julio C

2011-08-01

327

Genetic Relationships Between Chondrules, Rims and Matrix  

NASA Technical Reports Server (NTRS)

The most primitive chondrites are composed of chondrules and chondrule fragments, various types of inclusions, discrete mineral grains, metal, sulfides, and fine-grained materials that occur as interchondrule matrix and as chondrule/inclusion rims. Understanding how these components are related is essential for understanding how chondrites and their constituents formed and were processed in the solar nebula. For example, were the first generations of chondrules formed by melting of matrix or matrix precursors? Did chondrule formation result in appreciable transfer of chondrule material into the matrix? Here, we consider three types of data: 1) compositional data for bulk chondrites and matrix, 2) mineralogical and textural information, and 3) the abundances and characteristics of presolar materials that reside in the matrix and rims. We use these data to evaluate the roles of evaporation and condensation, chondrule formation, mixing of different nebular components, and secondary processing both in the nebula and on the parent bodies. Our goal is to identify the things that are reasonably well established and to point out the areas that need additional work.

Huss, G. R.; Alexander, C. M. OD.; Palme, H.; Bland, P. A.; Wasson, J. T.

2004-01-01

328

Temperature dependent nonlinear metal matrix laminae behavior  

NASA Technical Reports Server (NTRS)

An analytical method is described for computing the nonlinear thermal and mechanical response of laminated plates. The material model focuses upon the behavior of metal matrix materials by relating the nonlinear composite response to plasticity effects in the matrix. The foundation of the analysis is the unidirectional material model which is used to compute the instantaneous properties of the lamina based upon the properties of the fibers and matrix. The unidirectional model assumes that the fibers properties are constant with temperature and assumes that the matrix can be modelled as a temperature dependent, bilinear, kinematically hardening material. An incremental approach is used to compute average stresses in the fibers and matrix caused by arbitrary mechanical and thermal loads. The layer model is incorporated in an incremental laminated plate theory to compute the nonlinear response of laminated metal matrix composites of general orientation and stacking sequence. The report includes comparisons of the method with other analytical approaches and compares theoretical calculations with measured experimental material behavior. A section is included which describes the limitations of the material model.

Barrett, D. J.; Buesking, K. W.

1986-01-01

329

Method of producing a hybrid matrix fiber composite  

DOEpatents

Hybrid matrix fiber composites having enhanced compressive performance as well as enhanced stiffness, toughness and durability suitable for compression-critical applications. The methods for producing the fiber composites using matrix hybridization. The hybrid matrix fiber composites comprised of two chemically or physically bonded matrix materials, whereas the first matrix materials are used to impregnate multi-filament fibers formed into ribbons and the second matrix material is placed around and between the fiber ribbons that are impregnated with the first matrix material and both matrix materials are cured and solidified.

Deteresa, Steven J. (Livermore, CA); Lyon, Richard E. (Absecon, NJ); Groves, Scott E. (Brentwood, CA)

2006-03-28

330

INTEGRATED COI S200 - Hi-NiCalon FIBER WITH AN S200 MATRIX (POLYMER MATRIX COMPOSITE - PMC) / AETB 1  

NASA Technical Reports Server (NTRS)

INTEGRATED COI S200 - Hi-NiCalon FIBER WITH AN S200 MATRIX (POLYMER MATRIX COMPOSITE - PMC) / AETB 16 (FOAM CORE) / CARBON REINFORCED CYANOESTER (CERAMIC MATRIX COMPOSITE - CMC) HOT STRUCTURE, PANEL 884-1: SAMPLE 3

2003-01-01

331

INTEGRATED COI S200 - Hi-NiCalon FIBER WITH AN S200 MATRIX (POLYMER MATRIX COMPOSITE - PMC) / AETB 1  

NASA Technical Reports Server (NTRS)

INTEGRATED COI S200 - Hi-NiCalon FIBER WITH AN S200 MATRIX (POLYMER MATRIX COMPOSITE - PMC) / AETB 16 (FOAM CORE) / CARBON REINFORCED CYANOESTER (CERAMIC MATRIX COMPOSITE - CMC) HOT STRUCTURE, PANEL 884-1: SAMPLE 1

2003-01-01

332

Matrix cracking in unidirectional ceramic matrix composites under quasi-static and cyclic loading  

Microsoft Academic Search

Experimental data associated with the development of matrix cracks in unidirectional continuous silicon carbide fiber\\/calcium alumino-silicate matrix laminates under quasi-static loading are presented, including crack density, residual strain and hysteresis behavior as functions of applied stress. Simple models are developed, based on an assumption of purely frictional load transfer between the fiber and matrix, which describe reasonably well the quasi-static

A. W. Pryce; P. A. Smith

1993-01-01

333

Fiber-matrix interfacial characteristics in a fiber-reinforced ceramic matrix composite  

Microsoft Academic Search

Fiber-matrix interfacial shear stress and mechanical properties in oxide-matrix composites uniaxially reinforced with either uncoated or coated silicon carbide filaments were measured in the as-fabricated state, and following a thermal treatment at 1300 C for 100 h. All the tested composites showed higher fiber-matrix interfacial debond stress than the frictional stress, and toughened-composite behavior. Mechanical properties of composites reinforced with

Raj N. Singh

1989-01-01

334

Bäcklund transformation of matrix equations and a discrete matrix first Painlevé equation  

NASA Astrophysics Data System (ADS)

We show that the known auto-Bäcklund transformation for the matrix second Painlevé equation can be generalized to a much wider class of equations. This auto-Bäcklund transformation is an involution and so cannot be used on its own to generate an infinite sequence of different solutions, although for particular equations a second auto-Bäcklund transformation allows this to be done. We also give a Bäcklund transformation for this general class of matrix equations. For the matrix second Painlevé equation we also give a coalescence limit, and a construction of special integrals and of a discrete matrix first Painlevé equation.

Gordoa, P. R.; Pickering, A.; Zhu, Z. N.

2013-08-01

335

Thermal shock resistance of ceramic matrix composites  

NASA Technical Reports Server (NTRS)

The experimental and analytical investigation of the thermal shock phenomena in ceramic matrix composites is detailed. The composite systems examined were oxide-based, consisting of an aluminosilicate matrix with either polycrystalline aluminosilicate or single crystal alumina fiber reinforcement. The program was divided into three technical tasks; baseline mechanical properties, thermal shock modeling, and thermal shock testing. The analytical investigation focused on the development of simple expressions for transient thermal stresses induced during thermal shock. The effect of various material parameters, including thermal conductivity, elastic modulus, and thermal expansion, were examined analytically for their effect on thermal shock performance. Using a simple maximum stress criteria for each constituent, it was observed that fiber fracture would occur only at the most extreme thermal shock conditions and that matrix fracture, splitting parallel to the reinforcing fiber, was to be expected for most practical cases. Thermal shock resistance for the two material systems was determined experimentally by subjecting plates to sudden changes in temperature on one surface while maintaining the opposite surface at a constant temperature. This temperature change was varied in severity (magnitude) and in number of shocks applied to a given sample. The results showed that for the most severe conditions examined that only surface matrix fracture was present with no observable fiber fracture. The impact of this damage on material performance was limited to the matrix dominated properties only. Specifically, compression strength was observed to decrease by as much as 50 percent from the measured baseline.

Carper, D. M.; Nied, H. F.

1993-01-01

336

Matrix Metalloproteinase Control of Capillary Morphogenesis  

PubMed Central

Matrix metalloproteinases (MMPs) play crucial roles in a variety of normal (e.g. blood vessel formation, bone development) and pathophysiological (e.g. wound healing, cancer) processes. This is not only due to their ability to degrade the surrounding extracellular matrix (ECM), but also because MMPs function to reveal cryptic matrix binding sites, release matrix-bound growth factors inherent to these processes, and activate a variety of cell surface molecules. The process of blood vessel formation, in particular, is regulated by what is widely classified as the angiogenic switch: a mixture of both pro- and anti-angiogenic factors that function to counteract each other unless the stimuli from one side exceeds the other to disrupt the quiescent state. While it was initially thought that MMPs were strictly pro-angiogenic, new functions for this proteolytic family such as mediating vascular regression and generating matrix fragments with antiangiogenic capacities have been discovered in the last decade. These findings cast MMPs as multi-faceted pro- and anti-angiogenic effectors. The purpose of this review is to introduce the reader to the general structure and characterization of the MMP family and to discuss the temporal and spatial regulation of their gene expression and enzymatic activity in the following crucial steps associated with angiogenesis: degradation of the vascular basement membrane; proliferation and invasion of endothelial cells within the subjacent ECM, organization into immature tubules; maturation of these nascent vessels; and the pruning and regression of the vascular network. PMID:18540825

Ghajar, Cyrus M; George, Steven C; Putnam, Andrew J

2010-01-01

337

Estimating the Inertia Matrix of a Spacecraft  

NASA Technical Reports Server (NTRS)

A paper presents a method of utilizing some flight data, aboard a spacecraft that includes reaction wheels for attitude control, to estimate the inertia matrix of the spacecraft. The required data are digitized samples of (1) the spacecraft attitude in an inertial reference frame as measured, for example, by use of a star tracker and (2) speeds of rotation of the reaction wheels, the moments of inertia of which are deemed to be known. Starting from the classical equations for conservation of angular momentum of a rigid body, the inertia-matrix-estimation problem is formulated as a constrained least-squares minimization problem with explicit bounds on the inertia matrix incorporated as linear matrix inequalities. The explicit bounds reflect physical bounds on the inertia matrix and reduce the volume of data that must be processed to obtain a solution. The resulting minimization problem is a semidefinite optimization problem that can be solved efficiently, with guaranteed convergence to the global optimum, by use of readily available algorithms. In a test case involving a model attitude platform rotating on an air bearing, it is shown that, relative to a prior method, the present method produces better estimates from few data.

Acikmese, Behcet; Keim, Jason; Shields, Joel

2007-01-01

338

Google matrix analysis of DNA sequences  

E-print Network

For DNA sequences of various species we construct the Google matrix G of Markov transitions between nearby words composed of several letters. The statistical distribution of matrix elements of this matrix is shown to be described by a power law with the exponent being close to those of outgoing links in such scale-free networks as the World Wide Web (WWW). At the same time the sum of ingoing matrix elements is characterized by the exponent being significantly larger than those typical for WWW networks. This results in a slow algebraic decay of the PageRank probability determined by the distribution of ingoing elements. The spectrum of G is characterized by a large gap leading to a rapid relaxation process on the DNA sequence networks. We introduce the PageRank proximity correlator between different species which determines their statistical similarity from the view point of Markov chains. The properties of other eigenstates of the Google matrix are also discussed. Our results establish scale-free features of ...

Kandiah, Vivek

2013-01-01

339

Thermal stress effects in intermetallic matrix composites  

NASA Technical Reports Server (NTRS)

Intermetallic matrix composites develop residual stresses from the large thermal expansion mismatch (delta-alpha) between the fibers and matrix. This work was undertaken to: establish improved techniques to measure these thermal stresses in IMC's; determine residual stresses in a variety of IMC systems by experiments and modeling; and, determine the effect of residual stresses on selected mechanical properties of an IMC. X ray diffraction (XRD), neutron diffraction (ND), synchrotron XRD (SXRD), and ultrasonics (US) techniques for measuring thermal stresses in IMC were examined and ND was selected as the most promising technique. ND was demonstrated on a variety of IMC systems encompassing Ti- and Ni-base matrices, SiC, W, and Al2O3 fibers, and different fiber fractions (Vf). Experimental results on these systems agreed with predictions of a concentric cylinder model. In SiC/Ti-base systems, little yielding was found and stresses were controlled primarily by delta-alpha and Vf. In Ni-base matrix systems, yield strength of the matrix and Vf controlled stress levels. The longitudinal residual stresses in SCS-6/Ti-24Al-llNb composite were modified by thermomechanical processing. Increasing residual stress decreased ultimate tensile strength in agreement with model predictions. Fiber pushout strength showed an unexpected inverse correlation with residual stress. In-plane shear yield strength showed no dependence on residual stress. Higher levels of residual tension led to higher fatigue crack growth rates, as suggested by matrix mean stress effects.

Wright, P. K.; Sensmeier, M. D.; Kupperman, D. S.; Wadley, H. N. G.

1993-01-01

340

Recombinant Fibronectin Matrix Mimetics Specify Integrin Adhesion and Extracellular Matrix Assembly  

E-print Network

Recombinant Fibronectin Matrix Mimetics Specify Integrin Adhesion and Extracellular Matrix Assembly Daniel C. Roy, MS,1 and Denise C. Hocking, PhD1,2 Tissue engineering seeks to create functional tissues and organs by integrating natural or synthetic scaffolds with bioactive factors and cells. Creating

Goldman, Steven A.

341

Viewing Polynomial Roots With Matrix Eyes: Part 1: Irrational Roots via Matrix Dynamics  

E-print Network

1 Viewing Polynomial Roots With Matrix Eyes: Part 1: Irrational Roots via Matrix Dynamics Part 2 that converges to 0 #12;8 Dynamical View · Consider the orbits under repeated application of A starting from entries · Orbits from lattice points all converge to the line L · Let v be any integer vector. Let vn = A

Kalman, Dan

342

Numerical study on optimal Stirling engine regenerator matrix designs taking into account the effects of matrix  

E-print Network

Numerical study on optimal Stirling engine regenerator matrix designs taking into account matrix design that improves the efficiency of a Stirling engine has been developed in a numerical study of the existing SM5 Stirling engine. A new, detailed, one-dimensional Stirling engine model that delivers results

343

MatrixGuest Energy Transfer in Matrix-assisted Laser Desorption  

E-print Network

- tion of a succinic acid matrix at 2.94 µm leads to the excitation of the O­H stretching modes. Thus been studied on a model system comprising a pyridine-3-carboxylic acid matrix and leucine enkephalin by the application of the MALDI-MS method.1 Currently, the method is being applied towards sequencing of nucleo

Vertes, Akos

344

Cache oblivious storage and access heuristics for blocked matrix-matrix multiplication  

SciTech Connect

The authors investigate effects of ordering in blocked matrix-matrix multiplication. They find that submatrices do not have to be stored contiguously in memory in order to achieve near optimal performance. They also find a good choice of execution order of submatrix operations can lead to a speedup of up to four times for small block sizes.

Bock, Nicolas [Los Alamos National Laboratory; Rubensson, Emanuel H [Los Alamos National Laboratory; Niklasson, Anders M N [Los Alamos National Laboratory; Challacombe, Matt [Los Alamos National Laboratory; Salek, Pawel [SWEDEN

2008-01-01

345

48 CFR 1652.370 - Use of the matrix.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 true Use of the matrix. 1652.370 Section 1652.370 Federal...CLAUSES AND FORMS CONTRACT CLAUSES FEHBP Clause Matrix 1652.370 Use of the matrix. (a) The matrix in this section...

2010-10-01

346

48 CFR 2152.370 - Use of the matrix.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 true Use of the matrix. 2152.370 Section 2152.370 Federal...PROVISIONS AND CONTRACT CLAUSES Provision and Clause Matrix 2152.370 Use of the matrix. (a) The matrix in this section...

2010-10-01

347

The biofilm matrix – an immobilized but dynamic microbial environment  

Microsoft Academic Search

The biofilm matrix is a dynamic environment in which the component microbial cells appear to reach homeostasis and are optimally organized to make use of all available nutrients. The major matrix components are microbial cells, polysaccharides and water, together with excreted cellular products. The matrix therefore shows great microheterogeneity, within which numerous microenvironments can exist. Although exopolysaccharides provide the matrix

Ian W Sutherland

2001-01-01

348

Probabilistic micromechanics for metal matrix composites  

NASA Technical Reports Server (NTRS)

A probabilistic micromechanics-based nonlinear analysis procedure is developed to predict and quantify the variability in the properties of high temperature metal matrix composites. Monte Carlo simulation is used to model the probabilistic distributions of the constituent level properties including fiber, matrix, and interphase properties, volume and void ratios, strengths, fiber misalignment, and nonlinear empirical parameters. The procedure predicts the resultant ply properties and quantifies their statistical scatter. Graphite copper and Silicon Carbide Titanlum Aluminide (SCS-6 TI15) unidirectional plies are considered to demonstrate the predictive capabilities. The procedure is believed to have a high potential for use in material characterization and selection to precede and assist in experimental studies of new high temperature metal matrix composites.

Engelstad, S. P.; Reddy, J. N.; Hopkins, Dale A.

1991-01-01

349

Import of proteins into the peroxisomal matrix  

PubMed Central

Peroxisomes constitute a dynamic compartment in all nucleated cells. They fulfill diverse metabolic tasks in response to environmental changes and cellular demands. This adaptation is implemented by modulation of the enzyme content of the organelles, which is accomplished by dynamically operating peroxisomal protein transport machineries. Soluble import receptors recognize their newly synthesized cargo proteins in the cytosol and ferry them to the peroxisomal membrane. Subsequently, the cargo is translocated into the matrix, where the receptor is ubiquitinated and exported back to the cytosol for further rounds of matrix protein import. This review discusses the recent progress in our understanding of the peroxisomal matrix protein import and its regulation by ubiquitination events as well as the current view on the translocation mechanism of folded proteins into peroxisomes. This article is part of a Special Issue entitled: Origin and spatiotemporal dynamics of the peroxisomal endomembrane system. PMID:24069002

Hasan, Sohel; Platta, Harald W.; Erdmann, Ralf

2013-01-01

350

Introducing Matrix Operations through Biological Applications  

NSDL National Science Digital Library

For the Blue Waters Undergraduate Petascale Education Program (NSF), we developed a computational science module, "Living Links: Applications of Matrix Operations to Population Studies," which introduces matrix operations using applications to population studies and provides accompanying programs in a variety of systems (C/MPI, MATLAB, Mathematica). The module provides a foundation for the use of matrix operations that are essential to modeling numerous computational science applications from population studies to social networks. This paper describes the module; details experiences using the material in two undergraduate courses (High Performance Computing and Linear Algebra) in 2010 and 2011 at Wofford College and two workshops for Ph.D. students at Monash University in Melbourne, Australia, in 2011; and describes refinements to the module based on suggestions in student and instructor evaluations.

Angela B. Shiflet

351

Sparse nonnegative matrix factorization with ?0-constraints  

PubMed Central

Although nonnegative matrix factorization (NMF) favors a sparse and part-based representation of nonnegative data, there is no guarantee for this behavior. Several authors proposed NMF methods which enforce sparseness by constraining or penalizing the ?1-norm of the factor matrices. On the other hand, little work has been done using a more natural sparseness measure, the ?0-pseudo-norm. In this paper, we propose a framework for approximate NMF which constrains the ?0-norm of the basis matrix, or the coefficient matrix, respectively. For this purpose, techniques for unconstrained NMF can be easily incorporated, such as multiplicative update rules, or the alternating nonnegative least-squares scheme. In experiments we demonstrate the benefits of our methods, which compare to, or outperform existing approaches. PMID:22505792

Peharz, Robert; Pernkopf, Franz

2012-01-01

352

Matrix Downdating Techniques For Signal Processing  

NASA Astrophysics Data System (ADS)

We are concerned with a problem of finding the triangular (Banachiewicz-Cholesky) factor of the covariance matrix after deleting observations from the corresponding linear least squares equations. Such a problem, often referred to as downdating, arises in classical signal processing as well as in various other broad ares of computing. Examples include recursive least squares estimation and filtering with a sliding rectangular window in adaptive signal processing, outlier suppression and robust regression in statistics, and the modification of Hessian matrices in the numerical solution of non-linear equations. Formally the problem can be described as follows: Given an n xn upper triangular matrix L and an n-dimensional vector x such that LTL - xxT > 0 find an n xn lower triangular matrix L such that LLT = LLT - XXT We will look at the following issues relevant to the downdating problem: - stability - rank-1 downdating algorithms - generalization to modifications of a higher rank

Bojanczyk, Adam W.; Steinhardt, Allan O.

1988-02-01

353

t matrix of metallic wire structures  

SciTech Connect

To study the electromagnetic resonance and scattering properties of complex structures of which metallic wire structures are constituents within multiple scattering theory, the t matrix of individual structures is needed. We have recently developed a rigorous and numerically efficient equivalent circuit theory in which retardation effects are taken into account for metallic wire structures. Here, we show how the t matrix can be calculated analytically within this theory. We illustrate our method with the example of split ring resonators. The density of states and cross sections for scattering and absorption are calculated, which are shown to be remarkably enhanced at resonant frequencies. The t matrix serves as the basic building block to evaluate the interaction of wire structures within the framework of multiple scattering theory. This will open the door to efficient design and optimization of assembly of wire structures.

Zhan, T. R., E-mail: phystrzhan@gmail.com; Chui, S. T., E-mail: chui@bartol.udel.edu [Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (United States)

2014-04-14

354

Propulsive matrix of a helical flagellum  

NASA Astrophysics Data System (ADS)

We study the propulsion matrix of bacterial flagella numerically using slender body theory and the regularized Stokeslet method in a biologically relevant parameter regime. All three independent elements of the matrix are measured by computing propulsive force and torque generated by a rotating flagellum, and the drag force on a translating flagellum. Numerical results are compared with the predictions of resistive force theory, which is often used to interpret micro-organism propulsion. Neglecting hydrodynamic interactions between different parts of a flagellum in resistive force theory leads to both qualitative and quantitative discrepancies between the theoretical prediction of resistive force theory and the numerical results. We improve the original theory by empirically incorporating the effects of hydrodynamic interactions and propose new expressions for propulsive matrix elements that are accurate over the parameter regime explored.

Zhang, He-Peng; Liu, Bin; Bruce, Rodenborn; Harry, L. Swinney

2014-11-01

355

The transfer matrix: a geometrical perspective  

E-print Network

We present a comprehensive and self-contained discussion of the use of the transfer matrix to study propagation in one-dimensional lossless systems, including a variety of examples, such as superlattices, photonic crystals, and optical resonators. In all these cases, the transfer matrix has the same algebraic properties as the Lorentz group in a (2+1)-dimensional spacetime, as well as the group of unimodular real matrices underlying the structure of the abcd law, which explains many subtle details. We elaborate on the geometrical interpretation of the transfer-matrix action as a mapping on the unit disk and apply a simple trace criterion to classify the systems into three types with very different geometrical and physical properties. This approach is applied to some practical examples and, in particular, an alternative framework to deal with periodic (and quasiperiodic) systems is proposed.

L. L. Sanchez-Soto; J. J. Monzon; A. G. Barriuso; J. F. Carinena

2012-05-07

356

Another Conjecture about M(atrix) Theory  

E-print Network

The current understanding of M(atrix) theory is that in the large N limit certain supersymmetric Yang Mills theories become equivalent to M-theory in the infinite momentum frame. In this paper the conjecture is put forward that the equivalence between M and M(atrix) theory is not limited to the large N limit but is valid for finite N. It is argued that a light cone description of M-theory exists in which one of the light like coordinates is periodically identified. In the light cone literature this is called Discrete Light Cone Quantization (DLCQ). In this framework an exact light cone description exists for each quantized value N of longitudinal momentum. The new conjecture states that the sector of the DLCQ of M-theory is exactly described by a U(N) matrix theory. Evidence is presented for the conjecture.

Leonard Susskind

1997-04-10

357

Statistical properties of random matrix product states  

SciTech Connect

We study the set of random matrix product states (RMPS) introduced by Garnerone, de Oliveira, and Zanardi [S. Garnerone, T. R. de Oliveira, and P. Zanardi, Phys. Rev. A 81, 032336 (2010)] as a tool to explore foundational aspects of quantum statistical mechanics. In the present work, we provide an accurate numerical and analytical investigation of the properties of RMPS. We calculate the average state of the ensemble in the nonhomogeneous case, and numerically check the validity of this result. We also suggest using RMPS as a tool to approximate properties of general quantum random states. The numerical simulations presented here support the accuracy and efficiency of this approximation. These results suggest that any generalized canonical state can be approximated with high probability by the reduced density matrix of a RMPS, if the average matrix product states coincide with the associated microcanonical ensemble.

Garnerone, Silvano; Oliveira, Thiago R. de; Haas, Stephan; Zanardi, Paolo [Department of Physics and Astronomy and Center for Quantum Information Science and Technology, University of Southern California, Los Angeles, California 90089 (United States)

2010-11-15

358

Nanomechanics of the Cartilage Extracellular Matrix  

NASA Astrophysics Data System (ADS)

Cartilage is a hydrated biomacromolecular fiber composite located at the ends of long bones that enables proper joint lubrication, articulation, loading, and energy dissipation. Degradation of extracellular matrix molecular components and changes in their nanoscale structure greatly influence the macroscale behavior of the tissue and result in dysfunction with age, injury, and diseases such as osteoarthritis. Here, the application of the field of nanomechanics to cartilage is reviewed. Nanomechanics involves the measurement and prediction of nanoscale forces and displacements, intra- and intermolecular interactions, spatially varying mechanical properties, and other mechanical phenomena existing at small length scales. Experimental nanomechanics and theoretical nanomechanics have been applied to cartilage at varying levels of material complexity, e.g., nanoscale properties of intact tissue, the matrix associated with single cells, biomimetic molecular assemblies, and individual extracellular matrix biomolecules (such as aggrecan, collagen, and hyaluronan). These studies have contributed to establishing a fundamental mechanism-based understanding of native and engineered cartilage tissue function, quality, and pathology.

Han, Lin; Grodzinsky, Alan J.; Ortiz, Christine

2011-08-01

359

Matrix metalloproteinases in kidney homeostasis and diseases  

PubMed Central

Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have been increasingly linked to both normal physiology and abnormal pathology in the kidney. Collectively able to degrade all components of the extracellular matrix, MMPs were originally thought to antagonize the development of fibrotic diseases solely through digestion of excessive matrix. However, increasing evidence has shown that MMPs play a wide variety of roles in regulating inflammation, epithelial-mesenchymal transition, cell proliferation, angiogenesis, and apoptosis. We now have robust evidence for MMP dysregulation in a multitude of renal diseases including acute kidney injury, diabetic nephropathy, glomerulonephritis, inherited kidney disease, and chronic allograft nephropathy. The goal of this review is to summarize current findings regarding the role of MMPs in kidney diseases as well as the mechanisms of action of this family of proteases. PMID:22492945

Tan, Roderick J.

2012-01-01

360

Space Shuttle communications RF switch matrix  

NASA Technical Reports Server (NTRS)

The Shuttle Orbiter communications equipment includes phase modulation (PM) and frequency modulation (FM) channels. The PM section has the capability of routing high levels of energy (175 W) from any one of four transmitters to any one of four antennas, mutually exclusive. The FM channel uses a maximum of 15-W power routed from either of two transmitters to one of two antennas, mutually exclusive. The paper describes the design and the theory of a logic-controlled RF switch matrix devised for the purposes cited. Both PM and FM channels are computer-controlled with manual overrides. The logic interface is realized with CMOS logic for low power consumption and high noise immunity. The interior of the switch matrix is maintained at a pressure of 15 psi (90% nitrogen, 10% helium) by an electron beam-welded encapsulation. The computational results confirm the viability of the RF switch matrix concept.

Winch, R.

1979-01-01

361

Google matrix analysis of directed networks  

E-print Network

In past ten years, modern societies developed enormous communication and social networks. Their classification and information retrieval processing become a formidable task for the society. Due to the rapid growth of World Wide Web, social and communication networks, new mathematical methods have been invented to characterize the properties of these networks on a more detailed and precise level. Various search engines are essentially using such methods. It is highly important to develop new tools to classify and rank enormous amount of network information in a way adapted to internal network structures and characteristics. This review describes the Google matrix analysis of directed complex networks demonstrating its efficiency on various examples including World Wide Web, Wikipedia, software architecture, world trade, social and citation networks, brain neural networks, DNA sequences and Ulam networks. The analytical and numerical matrix methods used in this analysis originate from the fields of Markov chains, quantum chaos and Random Matrix theory.

Leonardo Ermann; Klaus M. Frahm; Dima L. Shepelyansky

2014-09-01

362

Electrolyte matrix for molten carbonate fuel cells  

DOEpatents

A matrix is described for a carbonate electrolyte including a support material and an additive constituent having a relatively low melting temperature and a relatively high coefficient of thermal expansion. The additive constituent is from 3 to 45 weight percent of the matrix and is formed from raw particles whose diameter is in a range of 0.1 {micro}m to 20 {micro}m and whose aspect ratio is in a range of 1 to 50. High energy intensive milling is used to mix the support material and additive constituent during matrix formation. Also disclosed is the use of a further additive constituent comprising an alkaline earth containing material. The further additive is mixed with the support material using high energy intensive milling. 5 figs.

Huang, C.M.; Yuh, C.Y.

1999-02-09

363

Decorin modulates matrix mineralization in vitro  

NASA Technical Reports Server (NTRS)

Decorin (DCN), a member of small leucine-rich proteoglycans, is known to modulate collagen fibrillogenesis. In order to investigate the potential roles of DCN in collagen matrix mineralization, several stable osteoblastic cell clones expressing higher (sense-DCN, S-DCN) and lower (antisense-DCN, As-DCN) levels of DCN were generated and the mineralized nodules formed by these clones were characterized. In comparison with control cells, the onset of mineralization by S-DCN clones was significantly delayed; whereas it was markedly accelerated and the number of mineralized nodules was significantly increased in As-DCN clones. The timing of mineralization was inversely correlated with the level of DCN synthesis. In these clones, the patterns of cell proliferation and differentiation appeared unaffected. These results suggest that DCN may act as an inhibitor of collagen matrix mineralization, thus modulating the timing of matrix mineralization.

Mochida, Yoshiyuki; Duarte, Wagner R.; Tanzawa, Hideki; Paschalis, Eleftherios P.; Yamauchi, Mitsuo

2003-01-01

364

On matrix models of M5 branes  

NASA Astrophysics Data System (ADS)

We compare the (0,2) theory of the single M5 brane decoupled from gravity in the lightcone with transverse R4, and a matrix nmodel description in terms of quatum mechanics on instanton moduli space. We give some tests of the Matrix model in the case of multi-5-branes on R4. We We extract constraints on the operator content of the field theory of the multi-5-brane system by analyzing the Matrix model. We also begin a study of compactifications of the (0,2) theory in this framework, arguing that, for large compactification scale, the (0,2) theory is described by super-quantum mechanics on appropriate instanton moduli spaces.

Brodie, John; Ramgoolam, Sanjaye

1998-06-01

365

Density matrix of black hole radiation  

E-print Network

Hawking's model of black hole evaporation is not unitary and leads to a mixed density matrix for the emitted radiation, while the Page model describes a unitary evaporation process in which the density matrix evolves from an almost thermal state to a pure state. We compare a recently proposed model of semiclassical black hole evaporation to the two established models. In particular, we study the density matrix of the outgoing radiation and determine how the magnitude of the off-diagonal corrections differs for the three frameworks. For Hawking's model, we find power-law corrections to the two-point functions that induce exponentially suppressed corrections to the off-diagonal elements of the full density matrix. This verifies that the Hawking result is correct to all orders in perturbation theory and also allows one to express the full density matrix in terms of the single-particle density matrix. We then consider the semiclassical theory for which the corrections, being non-perturbative from an effective field-theory perspective, are much less suppressed and grow monotonically in time. In this case, the R\\'enyi entropy for the outgoing radiation is shown to grow linearly at early times; but this growth slows down and the entropy eventually starts to decrease at the Page time. In addition to comparing models, we emphasize the distinction between the state of the radiation emitted from a black hole, which is highly quantum, and that of the radiation emitted from a typical classical black body at the same temperature.

Lasma Alberte; Ram Brustein; Andrei Khmelnitsky; A. J. M. Medved

2015-02-09

366

Effective matrix acidizing in carbonates using microemulsions  

SciTech Connect

The process of matrix acidizing of oil reservoirs is described. It is designed to improve well productivity by increasing rock permeability in the region surrounding the wellbore. As resistance to flow is reduced, oil can move more easily to the wellbore and production increases. A reacting mixture, usually containing HCI for limestone and an HCI/HF mixture for sandstone, is pumped into the well at pressures low enough to avoid fracturing the formation rock or to open existing fractures. The goal is to achieve a somewhat uniform radial penetration of acid into the formation porespace. Partial dissolution of the matrix can then take place, and rock permeability is increased.

Hoefner, M.L.; Fogler, H.S.

1985-05-01

367

Imaging Podosome Dynamics and Matrix Degradation  

PubMed Central

Summary Invasive cell migration is critical for leukocyte trafficking into tissues. Podosomes are matrix-degrading adhesive structures that are formed by macrophages and are necessary for macrophage migration and invasion. Here, we describe methods for imaging and quantifying podosomes in primary human macrophages and in THP-1 cells, a monocyte cell line that can be differentiated to a macrophage-like state. Moreover, we outline detailed methods for live imaging of podosomes, which are highly dynamic, and for the quantification of rates of podosome turnover. Finally, we discuss methods for the quantitative analysis of matrix degradation on fluorescent-gelatin coated cover slips. PMID:21748673

Starnes, Taylor W.; Cortesio, Christa L.; Huttenlocher, Anna

2014-01-01

368

NbTi superconductors with aluminium matrix  

SciTech Connect

This paper reports that the authors designed, produced and studied NbTi composite superconductors with Al, or Al-alloy, or combined Al and Cu matrix, which have reduced weight. Wires of different design with 0.5-2.0 mm diameter were manufactured using hydrostatic extrusion. The weight reduction in comparison with the same filling factor copper matrix superconductor achieves 20-40%. The overall critical current density at 5 T magnetic field is (1.6-2.8) {center dot} 10{sup 9} A/cm{sup 2}.

Buryak, V.P.; Dugadko, A.B.; Mironova, O.N.; Petrusenko, A.I. (Donetsk Physico-Technical Inst., Ukranian SSR Sciences Academy, Donetsk (SU)); Bliznyuk, V.A.; Dolbinov, J.D.; Lykhin, V.A. (Experimental-Design Bureau GORIZONT, Moscow (SU))

1992-01-01

369

Tissue-equivalent detector photon response matrix  

SciTech Connect

As an integral part of an investigation into the adequacy of existing dosimetry systems and survey instruments, photon spectra at two locations around a boiling water reactor (BWR) needed to be determined. One of these areas was adjacent to the turbine where {sup 16}N photons are expected; the other was near the residual heat removal system where {sup 60}Co photons were anticipated to dominate the spectrum. To perform the spectral measurements required, a response matrix for unfolding Compton recoil spectra was required. This paper details the generation of that matrix.

Lobdell, J.L. [Tennessee Valley Authority, Muscle Shoals, AL (United States); Hertel, N.E.

1995-12-31

370

L-Functions and Random Matrix Theory  

NSDL National Science Digital Library

This site highlights some of the conjectures and open problems concerning L-functions, with emphasis on the areas in which there has been recent progress using results from Random Matrix Theory. The main page's index links to short articles on such topics as the GUE Hypothesis, Zeros and Primes, and Extremal Problems. The site comes from the American Institute of Mathematics, which has posted these problems to go along with their workshop on L-Functions and Random Matrix Theory, held May 14-18, 2001.

371

Noncommutative static strings from matrix models  

NASA Astrophysics Data System (ADS)

We examine the noncommutative cylinder solution to a matrix model with a Minkowski background metric. It can be regarded as the noncommutative analogue of a static circular string. Perturbations about the solution yield a tachyonic scalar field (and an additional tachyonic fermion in the full supersymmetric version of the model) in the commutative limit. The tachyonic mode is attributed to the fact that the circular string is unstable under uniform adiabatic deformations. We obtain a stabilizing term which, when added to the matrix model, removes the tachyonic mass.

Stern, A.

2014-05-01

372

Unitary integrals and related matrix models  

NASA Astrophysics Data System (ADS)

We briefly review the basic properties of unitary matrix integrals, using three matrix models to analyze their properties: the ordinary unitary, the Brezin—Gross—Witten, and the Harish—Chandra—Itzykson—Zuber models. We especially emphasize the nontrivial aspects of the theory, from the De Witt’Hooft anomaly in unitary integrals to the problem of calculating correlators with the Itzykson-Zuber measure. We emphasize the method of character expansions as a technical tool. Unitary integrals are still insufficiently investigated, and many new results should be expected as this field attracts increased attention.

Morozov, A. Yu.

2010-01-01

373

Novel formulations of CKM matrix renormalization  

SciTech Connect

We review two recently proposed on-shell schemes for the renormalization of the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix in the Standard Model. One first constructs gauge-independent mass counterterm matrices for the up- and down-type quarks complying with the hermiticity of the complete mass matrices. Diagonalization of the latter then leads to explicit expressions for the CKM counterterm matrix, which are gauge independent, preserve unitarity, and lead to renormalized amplitudes that are non-singular in the limit in which any two quarks become mass degenerate. One of the schemes also automatically satisfies flavor democracy.

Kniehl, Bernd A. [II. Institut fuer Theoretische Physik, Universitaet Hamburg, Lumper Chaussee 149, 22761 Hamburg (Germany); Sirlin, Alberto [Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)

2009-12-17

374

Analytical solutions to matrix diffusion problems  

NASA Astrophysics Data System (ADS)

We report an analytical method to solve in a few cases of practical interest the equations which have traditionally been proposed for the matrix diffusion problem. In matrix diffusion, elements dissolved in ground water can penetrate the porous rock surronding the advective flow paths. In the context of radioactive waste repositories this phenomenon provides a mechenism by which the area of rock surface in contact with advecting elements is greatly enhaced, and can thus be an important delay mechanism. The cases solved are relevant for laborary as well for in situ experiments. Solutions are given as integral representations well suited for easy numerical solution.

Kekäläinen, Pekka

2014-10-01

375

HXeOBr in a xenon matrix  

SciTech Connect

We report on a new noble-gas molecule HXeOBr prepared in a low-temperature xenon matrix from the HBr and N{sub 2}O precursors by UV photolysis and thermal annealing. This molecule is assigned with the help of deuteration experiments and ab initio calculations including anharmonic methods. The H-Xe stretching frequency of HXeOBr is observed at 1634 cm{sup -1}, which is larger by 56 cm{sup -1} than the frequency of HXeOH identified previously. The experiments show a higher thermal stability of HXeOBr molecules in a xenon matrix compared to HXeOH.

Khriachtchev, Leonid; Tapio, Salla; Domanskaya, Alexandra V.; Raesaenen, Markku [Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 (Finland); Isokoski, Karoliina [Sackler Laboratory for Astrophysics, Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Lundell, Jan [Department of Chemistry, University of Jyvaeskylae, P.O. Box 35, FIN-40014 Jyvaeskylae (Finland)

2011-03-28

376

General Polarization Matrix of Electromagnetic Radiation  

E-print Network

A general form of the polarization matrix valid for any type of electromagnetic radiation (plane waves, multipole radiation etc.) is defined in terms of a certain bilinear form in the field-strength tensor. The quantum counterpart is determined as an operator matrix with normal-ordered elements with respect to the creation and annihilation operators. The zero-point oscillations (ZPO) of polarization are defined via difference between the anti-normal and normal ordered operator polarization matrices. It is shown that ZPO of the multipole field are stronger than those described by the model of plane waves and are concentrated in a certain neighborhood of a local source.

Muhammet Ali Can; Alexander S. Shumovsky

2001-05-15

377

Reaction kinetics between fiber and matrix  

NASA Technical Reports Server (NTRS)

Interdiffusion and interdiffusion controlled intermediate phase formation in metal matrix composites can be of interest for the prolonged application of these systems at high temperatures. Methods are discussed that address the kinetics of interdiffusion in systems that exhibit solid solution intermixing or the formation of a third intermediate phase at the fiber/matrix interface, or both. The tungsten fiber reinforced niobium and tungsten fiber reinforced superalloy systems are employed as model systems for experimentation and discussion. In an effort to impede interdiffusion, the concept of ion implanted diffusion barriers have been examined. Preliminary results on the feasibility and effectiveness of ion implanted diffusion barriers are presented.

Kopp, M. W.; Tien, J. K.; Petrasek, D. W.

1988-01-01

378

Ceramic Matrix Composite (CMC) Materials Characterization  

NASA Technical Reports Server (NTRS)

Under the former NASA EPM Program, much initial progress was made in identifying constituent materials and processes for SiC/SiC ceramic composite hot-section components. This presentation discusses the performance benefits of these approaches and elaborates on further constituent and property improvements made under NASA UEET. These include specific treatments at NASA that significantly improve the creep and environmental resistance of the Sylramic(TM) SiC fiber as well as the thermal conductivity and creep resistance of the CVI Sic matrix. Also discussed are recent findings concerning the beneficial effects of certain 2D-fabric architectures and carbon between the BN interphase coating and Sic matrix.

Calomino, Anthony

2001-01-01

379

Ceramic Matrix Composite (CMC) Materials Development  

NASA Technical Reports Server (NTRS)

Under the former NASA EPM Program, much initial progress was made in identifying constituent materials and processes for SiC/SiC ceramic composite hot-section components. This presentation discusses the performance benefits of these approaches and elaborates on further constituent and property improvements made under NASA UEET. These include specific treatments at NASA that significantly improve the creep and environmental resistance of the Sylramic(TM) Sic fiber as well as the thermal conductivity and creep resistance of the CVI Sic matrix. Also discussed are recent findings concerning the beneficial effects of certain 2D-fabric architectures and carbon between the BN interphase coating and Sic matrix.

DiCarlo, James

2001-01-01

380

Determinant Formulas for Matrix Model Free Energy  

E-print Network

The paper contains a new non-perturbative representation for subleading contribution to the free energy of multicut solution for hermitian matrix model. This representation is a generalisation of the formula, proposed by Klemm, Marino and Theisen for two cut solution, which was obtained by comparing the cubic matrix model with the topological B-model on the local Calabi-Yau geometry $\\hat {II}$ and was checked perturbatively. In this paper we give a direct proof of their formula and generalise it to the general multicut solution.

D. Vasiliev

2005-07-11

381

Analytical solutions to matrix diffusion problems  

SciTech Connect

We report an analytical method to solve in a few cases of practical interest the equations which have traditionally been proposed for the matrix diffusion problem. In matrix diffusion, elements dissolved in ground water can penetrate the porous rock surronuding the advective flow paths. In the context of radioactive waste repositories this phenomenon provides a mechanism by which the area of rock surface in contact with advecting elements is greatly enhanced, and can thus be an important delay mechanism. The cases solved are relevant for laboratory as well for in situ experiments. Solutions are given as integral representations well suited for easy numerical solution.

Kekäläinen, Pekka, E-mail: pekka.kekalainen@helsinki.fi [Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, FIN-00014 University of Helsinki (Finland)

2014-10-06

382

Triminimal parametrization of quark mixing matrix  

NASA Astrophysics Data System (ADS)

Starting from a new zeroth order basis for quark mixing (CKM) matrix based on the quark-lepton complementarity and the tribimaximal pattern of lepton mixing, we derive a triminimal parametrization of a CKM matrix with three small angles and a CP-violating phase as its parameters. This new triminimal parametrization has the merits of fast convergence and simplicity in application. With the quark-lepton complementary relations, we derive relations between the two unified triminimal parametrizations for quark mixing obtained in this work and for lepton mixing obtained by Pakvasa-Rodejohann-Weiler. Parametrization deviating from quark-lepton complementarity is also discussed.

He, Xiao-Gang; Li, Shi-Wen; Ma, Bo-Qiang

2008-12-01

383

Polymeric matrix materials for infrared metamaterials  

DOEpatents

A polymeric matrix material exhibits low loss at optical frequencies and facilitates the fabrication of all-dielectric metamaterials. The low-loss polymeric matrix material can be synthesized by providing an unsaturated polymer, comprising double or triple bonds; partially hydrogenating the unsaturated polymer; depositing a film of the partially hydrogenated polymer and a crosslinker on a substrate; and photopatterning the film by exposing the film to ultraviolet light through a patterning mask, thereby cross-linking at least some of the remaining unsaturated groups of the partially hydrogenated polymer in the exposed portions.

Dirk, Shawn M; Rasberry, Roger D; Rahimian, Kamyar

2014-04-22

384

Modular Matrix Cipher and Its Application in Authentication Protocol  

Microsoft Academic Search

Matrix cryptosystems, like Hill cipher, are resistant to frequency analysis. The key is a non-singular k times k matrix, for example 3 times 3 matrix K. In this paper, we propose simple criteria to generate a modular non-singular key-matrix for matrix ciphers fast. We apply these results to cryptography and computer security. In this paper, we present a mutualauthentication protocol

Bao Ngoc Tran; Thuc Dinh Nguyen

2008-01-01

385

The Twisted Matrix: Dream, Simulation or Hybrid? to appear in C. Grau (ed) Philosophical Essays on the Matrix (Oxford University  

E-print Network

³The Twisted Matrix: Dream, Simulation or Hybrid?² to appear in C. Grau (ed) Philosophical Essays://whatisthematrix.warnerbros.com/rl_cmp/phi.html The Twisted Matrix: Dream, Simulation or Hybrid1? 1. Ambivalence "The Matrix is a computer-generated dreamworld built to keep us under control" Morpheus, early in The Matrix. " In dreaming, you are not only out

Clark, Andy

386

Matrix diffusion coefficients in volcanic rocks at the Nevada test site: Influence of matrix porosity, matrix permeability, and fracture coating minerals  

NASA Astrophysics Data System (ADS)

Diffusion cell experiments were conducted to measure nonsorbing solute matrix diffusion coefficients in forty-seven different volcanic rock matrix samples from eight different locations (with multiple depth intervals represented at several locations) at the Nevada Test Site. The solutes used in the experiments included bromide, iodide, pentafluorobenzoate (PFBA), and tritiated water ( 3HHO). The porosity and saturated permeability of most of the diffusion cell samples were measured to evaluate the correlation of these two variables with tracer matrix diffusion coefficients divided by the free-water diffusion coefficient ( Dm/ D*). To investigate the influence of fracture coating minerals on matrix diffusion, ten of the diffusion cells represented paired samples from the same depth interval in which one sample contained a fracture surface with mineral coatings and the other sample consisted of only pure matrix. The log of ( Dm/ D*) was found to be positively correlated with both the matrix porosity and the log of matrix permeability. A multiple linear regression analysis indicated that both parameters contributed significantly to the regression at the 95% confidence level. However, the log of the matrix diffusion coefficient was more highly-correlated with the log of matrix permeability than with matrix porosity, which suggests that matrix diffusion coefficients, like matrix permeabilities, have a greater dependence on the interconnectedness of matrix porosity than on the matrix porosity itself. The regression equation for the volcanic rocks was found to provide satisfactory predictions of log( Dm/ D*) for other types of rocks with similar ranges of matrix porosity and permeability as the volcanic rocks, but it did a poorer job predicting log( Dm/ D*) for rocks with lower porosities and/or permeabilities. The presence of mineral coatings on fracture walls did not appear to have a significant effect on matrix diffusion in the ten paired diffusion cell experiments.

Reimus, Paul W.; Callahan, Timothy J.; Ware, S. Doug; Haga, Marc J.; Counce, Dale A.

2007-08-01

387

The origin of chondrules: Constraints from matrix composition and matrix-chondrule complementarity  

NASA Astrophysics Data System (ADS)

One of the major unresolved problems in cosmochemistry is the origin of chondrules, once molten, spherical silicate droplets with diameters of 0.2 to 2 mm. Chondrules are an essential component of primitive meteorites and perhaps of all early solar system materials including the terrestrial planets. Numerous hypotheses have been proposed for their origin. Many carbonaceous chondrites are composed of about equal amounts of chondrules and fine-grained matrix. Recent data confirm that matrix in carbonaceous chondrites has high Si/Mg and Fe/Mg ratios when compared to bulk carbonaceous chondrites with solar abundance ratios. Chondrules have the opposite signature, low Si/Mg and Fe/Mg ratios. In some carbonaceous chondrites chondrules have low Al/Ti ratios, matrix has the opposite signature and the bulk is chondritic. It is shown in detail that these complementary relationships cannot have evolved on the parent asteroid(s) of carbonaceous chondrites. They reflect preaccretionary processes. Both chondrules and matrix must have formed from a single, solar-like reservoir. Consequences of complementarity for chondrule formation models are discussed. An independent origin and/or random mixing of chondrules and matrix can be excluded. Hence, complementarity is a strong constraint for all astrophysical-cosmochemical models of chondrule formation. Although chondrules and matrix formed from a single reservoir, the chondrule-matrix system was open to the addition of oxygen and other gaseous components.

Palme, Herbert; Hezel, Dominik C.; Ebel, Denton S.

2015-02-01

388

Spectral Design for Matrix Hamiltonians: Different Methods of Constructing of a Matrix Intertwining Operator  

E-print Network

We study intertwining relations for $n\\times n$ matrix non-Hermitian, in general, one-dimensional Hamiltonians by $n\\times n$ matrix linear differential operators with nondegenerate coefficients at $d/dx$ in the highest degree. Some methods of constructing of $n\\times n$ matrix intertwining operator of the first order of general form are proposed and their interrelation is examined. As example we construct $2\\times2$ matrix Hamiltonian of general form intertwined by operator of the first order with the Hamiltonian with zero matrix potential. It is shown that one can add for the final $2\\times2$ matrix Hamiltonian with respect to the initial matrix Hamiltonian with the help of intertwining operator of the first order either up to two bound states for different energy values or up to two bound states described by vector-eigenfunctions for the same energy value or up to two bound states described by vector-eigenfunction and associated vector-function for the same energy value.

Andrey V. Sokolov

2014-07-19

389

Spectral design for matrix Hamiltonians: different methods of constructing of a matrix intertwining operator  

NASA Astrophysics Data System (ADS)

We study relations describing the intertwining of n × n matrix, in general non-Hermitian, one-dimensional Hamiltonians by n× n matrix linear differential operators with nondegenerate coefficients of d/dx in the highest degree. Some methods for constructing n× n matrix intertwining operators of the first order of general form are proposed and their interrelations are examined. We construct, as an example, a 2 × 2 matrix Hamiltonian of general form intertwined by an operator of the first order with the Hamiltonian with zero matrix potential. It is shown that one can add, for the final 2 × 2 matrix Hamiltonian with respect to the initial matrix Hamiltonian, with the help of an intertwining operator of first order, up to two bound states for different energy values, or up to two bound states described by vector-eigenfunctions for the same energy value, or up to two bound states described by a vector-eigenfunction and an associated vector-function for the same energy value. This article is registered at http://arxiv.org/ under preprint number 1406.0191 [math-ph].

Sokolov, Andrey V.

2015-02-01

390

Parallel Programming with Matrix Distributed Processing  

E-print Network

Matrix Distributed Processing (MDP) is a C++ library for fast development of efficient parallel algorithms. It constitues the core of FermiQCD. MDP enables programmers to focus on algorithms, while parallelization is dealt with automatically and transparently. Here we present a brief overview of MDP and examples of applications in Computer Science (Cellular Automata), Engineering (PDE Solver) and Physics (Ising Model).

Massimo Di Pierro

2005-05-09

391

A Random Matrix Model of Black Holes  

E-print Network

A random matrix model of black holes is given based on analysis of Gaussian complex ensembles, based on the generalization of chRMT of QCD. Spacetime freedoms are incorporated in terms of eigenvalues of the ensemble. Classical observables of black holes can be computed using this model and it satisfies asymptotic freedom and holographic principle.

Da Xu

2008-06-23

392

Unitary Matrix Models and PAINLEVÉ III  

Microsoft Academic Search

We discussed the full unitary matrix models from the viewpoints of integrable equations and string equations. Coupling the Toda equations and the string equations, we derive a special case of the Painlevé III equation. From the Virasoro constraints, we can use the radial coordinate. The relation between t1 and t-1 is like the complex conjugate.

Masato Hisakado

1996-01-01

393

Scattering matrix approach to STW resonators  

Microsoft Academic Search

The scattering matrix method was used for the analysis of surface transverse wave (STW) resonators on quartz. An expression for the transfer function of the resonators with different numbers of electrodes in the reflectors was derived. It was found that, for a proper ratio of these numbers, the spurious signal level below the resonance frequency can be lowered. The STW

Waldemar Soluch

2002-01-01

394

Applying matrix quantization to isolated word recognition  

Microsoft Academic Search

A new approach to isolated word recognition is examined. This approach is based on an extension of vector quantization speech coding, called matrix quantization speech coding, that was developed by Tsao and Gray. In this new approach, a codebook containing a set of time-ordered-sequences of speech spectra represents each vocabulary word. A word is recognized by encoding it with each

David K. Burton

1985-01-01

395

An optical matrix-vector multiplier project  

Microsoft Academic Search

The implementation of an optical matrix vector multiplier (OMVM) as a project to demonstrate to undergraduates the parallel capabilities of computing with light, the advantages and disadvantages of analog computers, and noise considerations for accurate results is discussed. The OMVM is designed using waveguides and is interfaced to an Apple IIGS. Software and hardware designs are explained in detail. The

A. P. Ittycheriah; J. F. Walkup; T. F. Krile

1991-01-01

396

Fracture toughness testing of polymer matrix composites  

NASA Technical Reports Server (NTRS)

The experimental techniques and associated data analysis methods used to measure the resistance to interlaminar fracture, or 'fracture toughness', of polymer matrix composite materials are described. A review in the use of energy techniques to characterize fracture behavior in elastic solids is given. An overview is presented of the types of approaches employed in the design of delamination-resistant composite materials.

Grady, Joseph E.

1992-01-01

397

Nonspherical Giant Gravitons and Matrix Theory  

Microsoft Academic Search

We consider the plane wave limit of the nonspherical giant gravitons. We compute the Poisson brackets of the coordinate functions and find a nonlinear algebra. We show that this algebra solves the supersymmetry conditions of the matrix model. This is the generalization of the algebraic realization of the spherical membrane as the ``fuzzy sphere''. We describe finite dimensional representations of

Andrei Mikhailov

2002-01-01

398

Correlations between eigenvalues of a random matrix  

Microsoft Academic Search

Exact analytical expressions are found for the joint probability distribution functions ofn eigenvalues belonging to a random Hermitian matrix of orderN, wheren is any integer andN?8. The distribution functions, like those obtained earlier forn=2, involve only trigonometrical functions of the eigenvalue differences.

Freeman J. Dyson

1970-01-01

399

State reconstruction via infinite matrix inversion  

NASA Astrophysics Data System (ADS)

We consider the method of infinite matrix inversion in deriving state reconstruction formulae for phase-space distributions. As an example, we demonstrate the method in the case of the Cahill-Glauber s-parametrized quasiprobability distributions. We obtain two formulae by different means, both of which have different conditions for validity.

Schultz, Jussi

2010-09-01

400

["Archaic matrix of the oedipus complex"].  

PubMed

The clinical implication of Janine Chasseguet-Smirgel's concept of the "archaic matrix of the Oedipus complex" is examined, the resulting deeper understanding of the Oedipus myth is considered. A discussion follows of Chasseguet-Smirgel's way of using this concept in her historical evaluation of German Romantism with regard to the Nazi times and nowadays politics of the Westgerman Green Party. PMID:2251392

Vogt, R

1990-10-01

401

Human Resources Security Access Matrix Function Training  

E-print Network

June 2013 Human Resources Security Access Matrix Function Training Course Required Class Mode Training Course Prerequisite Security Access Form Required Contact for Additional Information Complete Electronic I-9 Forms REC001: I-9 /E-Verify Web Training OR Online OR None Electronic I-9 Security Access Form

Wu, Shin-Tson

402

Automatic Lag Selection in Covariance Matrix Estimation  

Microsoft Academic Search

The authors propose a nonparametric method for automatically selecting the number of autocovariances to use in computing a heteroskedasticity and autocorrelation consistent covariance matrix. For a given kernel for weighting the autocovariances, they prove that their procedure is asymptotically equivalent to one that is optimal under a mean-squared error loss function. Monte Carlo simulations suggest that the authors' procedure performs

Whitney K Newey; Kenneth D West

1994-01-01

403

Automatic Lag Selection in Covariance Matrix Estimation  

Microsoft Academic Search

We propose a nonparametric method for automatically selecting the number of autocovariances to use in computing a heteroskedasticity and autocorrelation consistent covariance matrix. For a given kernel for weighting the autocovariances, we prove that our procedure is asymptotically equivalent to one that is optimal under a mean squared error loss function. Monte Carlo simulations suggest that our procedure performs tolerably

Kenneth D. West; Whitney K. Newey

1995-01-01

404

Brain and CNS Histology Rules Matrix  

Cancer.gov

Malignant Meninges, Brain, Spinal Cord, Cranial Nerves, Pi tuitary gland, Craniopharyngeal duct and Pineal gland Histology Coding Rules – Matrix C700, C701, C709, C710-C719, C720-C725, C728, C729, C751-C753 (Excludes lymphoma and leukemia – M9590-9989

405

Brain and CNS Multiple Primary Rules Matrix  

Cancer.gov

Malignant Meninges, Brain, Spinal Cord, Cranial Nerves, Pi tuitary gland, Craniopharyngeal duct and Pineal gland Multiple Primary Rules – Matrix C700, C701, C709, C710-C719, C720-C725, C728, C729, C751-C753 (Excludes lymphoma and leukemia – M9590-9989

406

Matrix models from operators and topological strings  

E-print Network

We propose a new family of matrix models whose $1/N$ expansion captures the all-genus topological string on toric Calabi-Yau threefolds. These matrix models are constructed from the trace class operators appearing in the quantization of the corresponding mirror curves. The fact that they provide a non-perturbative realization of the (standard) topological string follows from a recent conjecture connecting the spectral properties of these operators, to the enumerative invariants of the underlying Calabi-Yau threefolds. We study in detail the resulting matrix models for some simple geometries, like local $\\mathbb P^2$ and local $\\mathbb F_2$, and we verify that their weak 't Hooft coupling expansion reproduces the topological string free energies near the conifold singularity. These matrix models are formally similar to those appearing in the Fermi-gas formulation of Chern-Simons-matter theories, and their $1/N$ expansion receives non-perturbative corrections determined by the Nekrasov-Shatashvili limit of the refined topological string.

Marcos Marino; Szabolcs Zakany

2015-02-10

407

Emerging Educational Institutional Decision-Making Matrix  

ERIC Educational Resources Information Center

The "emerging educational institutional decision-making matrix" is developed to allow educational institutions to adopt a rigorous and consistent methodology of determining which of the myriad of emerging educational technologies will be the most compelling for the institution, particularly ensuring that it is the educational or pedagogical but…

Ashford-Rowe, Kevin H.; Holt, Marnie

2011-01-01

408

Matrix of Hard and Soft Skills  

NSDL National Science Digital Library

This document was developed by Access Tech Careers to support successful course completion for students with learning disabilities. This matrix displays intersections between hard skills, including reading, writing, oral communication, and math, with soft skills, including critical thinking, teamwork, professionalism, and adaptability. It can help instructors integrate hard and soft skills in course planning.

409

The Bushido Matrix for Couple Communication  

ERIC Educational Resources Information Center

The concept of Japanese Bushido and its seven virtues were introduced by the authors in this article for the practice and application of couple communication. The Bushido Matrix Worksheet (BMW) was created for enhancing couple's awareness and understanding of each other's values and experiences. An activity and a case study to demonstrate the use…

Li, Chi-Sing; Lin, Yu-Fen; Ginsburg, Phil; Eckstein, Daniel

2012-01-01

410

PARTICIPANTS ATTENDING MATRIX SYMPOSIUM Gatlinburg, Tennessee  

E-print Network

PARTICIPANTS ATTENDING MATRIX SYMPOSIUM Gatlinburg, Tennessee April 13-18, 1964 Dr. Julius Albrecht Laboratory Mathematics Division P.O. Box X Oak Ridge, Tennessee Dr. Robert L. Causey Lockheed Missiles Ridge Gaseous Diffusion Plant P.O. Box P Ok Ridge, Tennessee Mr. John M. Gary National Center

Higham, Nicholas J.

411

Correlation matrix memories for knowledge manipulation  

Microsoft Academic Search

Extended Abstract. This talk will describe current w ork in the use of neural networks for fast matching in knowledge manipulation systems. The work builds upon work in the use of binary correlation matrix memories (CMM). Austin 1987, Austin et. al. 1994. The work differs from most of the work in the use of neural networks in kno wledge manipulation,

James Austin

412

CHAPTER TEN Matrix Regulation of Tumor-  

E-print Network

CHAPTER TEN Matrix Regulation of Tumor- Initiating Cells Sophie Y. Wong, Sanjay Kumar Department.1 What are tumor-initiating cells? 244 1.2 Significance of TICs 245 2. Identification and Isolation of mechanotransduction 250 4. Conclusion 251 References 252 Abstract The recognition that the progression of many tumors

Kumar, Sanjay

413

Polymer matrix electroluminescent materials and devices  

DOEpatents

Photoluminescent and electroluminescent compositions are provided which comprise a matrix comprising aromatic repeat units covalently coordinated to a phosphorescent or luminescent metal ion or metal ion complexes. Methods for producing such compositions, and the electroluminescent devices formed therefrom, are also disclosed.

Marrocco, III, Matthew L. (Fontana, CA); Motamedi, Farshad J. (Claremont, CA); Abdelrazzaq, Feras Bashir (Covina, CA); Abdelrazzaq, legal representative, Bashir Twfiq (Aman, JO)

2012-06-26

414

ON THE VANDERMONDE MATRIX Joseph J. Rushanan  

E-print Network

1 ) \\Delta \\Delta \\Delta (x \\Gamma ff n\\Gamma1 ): Let R be the ring of polynomials over F modulo fON THE VANDERMONDE MATRIX Joseph J. Rushanan The MITRE Corporation, M/S E025, Bedford, MA 01730(x), represented by all polynomials over F of degree less than n. We define a linear transformation ' on R to F n

Rushanan, Joe J.

415

S-matrix theory of nuclear forces  

SciTech Connect

The use of the S-matrix theory for deriving the nucleon-nucleon interaction is reviewed. Fits to recent NN data are described. Applications to nuclear structure properties and nucleon-nucleus reactions are also discussed, and the results compared with data. 20 references.

Vinh Mau, R.

1984-09-01

416

Science Unlimited: Grades K-6 Competency Matrix.  

ERIC Educational Resources Information Center

This competency matrix matches the primary and intermediate Science Unlimited lessons with the established competencies which appear in the Science Unlimited competency continuum. Primary lessons deal with: investigating dripping faucets; classification/sorting; smell; eyes; color; air; weather; observation and description; mystery boxes; change;…

Pennsylvania State Dept. of Education, Harrisburg. Div. of Arts and Sciences.

417

Evaluation of the Matrix Project. Interchange 77.  

ERIC Educational Resources Information Center

The Matrix Project is a program that has been established in central Scotland with the aim of reducing the risk of offending and anti-social behavior among vulnerable children. The project provides a range of services to children between eight and 11 years of age who are at risk in the local authority areas of Clackmannanshire, Falkirk and…

McIvor, Gill; Moodie, Kristina

418

Hypercontractivity in finite-dimensional matrix algebras  

NASA Astrophysics Data System (ADS)

We obtain hypercontractivity estimates for a large class of semigroups defined on finite-dimensional matrix algebras 𝕄n. These semigroups arise from Poisson-like length functions ? on ?n × ?n and provide new hypercontractive families of quantum channels when ? is conditionally negative. We also study the optimality of our estimates.

Junge, Marius; Palazuelos, Carlos; Parcet, Javier; Perrin, Mathilde

2015-02-01

419

A contribution to matrix quadratic equations  

Microsoft Academic Search

The well-known matrix algebraic equation of the optimal control and filtering theory is considered. A necessary and sufficient condition for its solution to yield an optimal as well as asymptotically stable closed-loop system is given. The condition involves the concepts of stabilizability and detectability.

V. Kucera

1972-01-01

420

Development projects scheduling and design structure matrix  

Microsoft Academic Search

Many researchers have highlighted weaknesses of traditional approaches, such as PERT and CPM, in scheduling product development projects and in particular their failure to model iteration. The design structure matrix (DSM) method provides a practical and useful tool to deal with this issue. The advantages of DSM representation and analysis techniques have led to their increasing use in project planning,

Y. J. Qian; T. N. Goh

2007-01-01

421

Rainflow Matrix for Switching Random Loads  

Microsoft Academic Search

A switching random load, which is a sequential mixture of different random subloads, is modelled by using a hidden Markov model. The basic assumptions are that the turning points of each subload is modelled by a Markov chain, and that the switching between the subloads follow a Markov chain. An algorithm for computing the rainflow matrix for such a load

Pär Johannesson

1998-01-01

422

Matrix Elements of Spin-Spin Interaction  

Microsoft Academic Search

An expansion of the spin-spin interaction operator allows a derivation of matrix elements using the methods of Racah. Formulas are given for configurations involving two nonequivalent electrons and for n equivalent electrons. Extension of the results to other configurations may be made using known procedures.

Frederick R. Innes

1953-01-01

423

Extracellular Matrix Metabolism in Diabetic Nephropathy  

Microsoft Academic Search

Diabetic nephropathy is characterized by excessive deposition of extracellular matrix proteins in the mesangium and basement membrane of the glomerulus and in the renal tubulointerstitium. This review summarizes the main changes in protein composition of the glomerular mesangium and base- ment membrane and the evidence that, in the mesangium, these are initiated by changes in glucose metabolism and the forma-

ROGER M. MASON; NADIA ABDEL WAHAB

2003-01-01

424

subspace accelerated matrix splitting algorithms for bound ...  

E-print Network

... phase employs matrix splitting iterations that are tailored to the structure of the ...... accept “large” subspace steps that make substantial progress towards a solution .... small since as we decrease ?k the right-hand side of (3.20) also changes.

2011-09-28

425

Revised planning matrix of quality function deployment  

Microsoft Academic Search

Quality function deployment (QFD) has been adopted to improve product quality and development in many fields. Numerous studies have demonstrated that attribute importance and attribute performance have a causal relationship and the customer self-stated raw importance is not the actual importance of a customer attribute. These findings generate questions regarding the applicability of the conventional planning matrix (PM) of QFD.

Wei-Jaw Deng; Ying-Feng Kuo

2008-01-01

426

User interface design with matrix algebra  

Microsoft Academic Search

It is usually very hard, both for designers and users, to reason reliably about user interfaces. This article shows that 'push button' and 'point and click' user interfaces are algebraic structures. Users effectively do algebra when they interact, and therefore we can be precise about some important design issues and issues of usability. Matrix algebra, in particular, is useful for

Harold W. Thimbleby

2004-01-01

427

Using a Matrix Model for Enrollment Management.  

ERIC Educational Resources Information Center

Introduces a method of examining college enrollment patterns that is unlike the traditional cohort models currently used. The student flow matrix model can track student retention and attrition within the institution, and can also help the administrator identify key relationships between and among specific student-flow characteristics. (MSE)

Luna, Andrew L.

1999-01-01

428

Taking Charge of Change Through Matrix Management.  

ERIC Educational Resources Information Center

Matrix management provides a flexible method of responding to today's complex challenges in a way that supports a traditional organization and at the same time recognizes the necessity to draw upon the total resource needs of the institution through project teams. Operation at Kings College is described. (MLW)

Farmer, D. W.

1987-01-01

429

Density-matrix quantum Monte Carlo method  

NASA Astrophysics Data System (ADS)

We present a quantum Monte Carlo method capable of sampling the full density matrix of a many-particle system at finite temperature. This allows arbitrary reduced density matrix elements and expectation values of complicated nonlocal observables to be evaluated easily. The method resembles full configuration interaction quantum Monte Carlo but works in the space of many-particle operators instead of the space of many-particle wave functions. One simulation provides the density matrix at all temperatures simultaneously, from T =? to T =0, allowing the temperature dependence of expectation values to be studied. The direct sampling of the density matrix also allows the calculation of some previously inaccessible entanglement measures. We explain the theory underlying the method, describe the algorithm, and introduce an importance-sampling procedure to improve the stochastic efficiency. To demonstrate the potential of our approach, the energy and staggered magnetization of the isotropic antiferromagnetic Heisenberg model on small lattices, the concurrence of one-dimensional spin rings, and the Renyi S2 entanglement entropy of various sublattices of the 6×6 Heisenberg model are calculated. The nature of the sign problem in the method is also investigated.

Blunt, N. S.; Rogers, T. W.; Spencer, J. S.; Foulkes, W. M. C.

2014-06-01

430

Quantum Dynamics and Random Matrix Theory  

E-print Network

We compute the survival probability of an initial state, with an energy in a certain window, by means of random matrix theory. We determine its probability distribution and show that is is universal, i.e. caracterised only by the symmetry class of the hamiltonian and independent of the initial state.

Herve Kunz

2002-01-28

431

Exercises with the universal R-matrix  

NASA Astrophysics Data System (ADS)

Using the formula for the universal R-matrix proposed by Khoroshkin and Tolstoy, we give a detailed derivation of L-operators for the quantum groups associated with the generalized Cartan matrices A(1)1 and A(1)2.

Boos, Herman; Göhmann, Frank; Klümper, Andreas; Nirov, Khazret S.; Razumov, Alexander V.

2010-10-01

432

Comix, a new matrix element generator  

E-print Network

We present a new tree-level matrix element generator, based on the recently introduced colour dressed Berends-Giele recursive relations. We discuss two new algorithms for phase space integration, dedicated to be used with large multiplicities and colour sampling.

Gleisberg, Tanju

2008-01-01

433

Nonnegative matrix factorization for polyphonic music transcription  

Microsoft Academic Search

We present a methodology for analyzing polyphonic musical passages comprised of notes that exhibit a harmonically fixed spectral profile (such as piano notes). Taking advantage of this unique note structure, we can model the audio content of the musical passage by a linear basis transform and use non-negative matrix decomposition methods to estimate the spectral profile and the temporal information

Paris Smaragdis; Judith C. Brown

2003-01-01

434

Light weight polymer matrix composite material  

NASA Technical Reports Server (NTRS)

A graphite fiber reinforced polymer matrix is layed up, cured, and thermally aged at about 750.degree. F. in the presence of an inert gas. The heat treatment improves the structural integrity and alters the electrical conductivity of the materials. In the preferred embodiment PMR-15 polyimides and Celion-6000 graphite fibers are used.

Bowles, Kenneth J. (Inventor); Lowell, Carl E. (Inventor)

1991-01-01

435

Critical state of sand matrix soils.  

PubMed

The Critical State Soil Mechanic (CSSM) is a globally recognised framework while the critical states for sand and clay are both well established. Nevertheless, the development of the critical state of sand matrix soils is lacking. This paper discusses the development of critical state lines and corresponding critical state parameters for the investigated material, sand matrix soils using sand-kaolin mixtures. The output of this paper can be used as an interpretation framework for the research on liquefaction susceptibility of sand matrix soils in the future. The strain controlled triaxial test apparatus was used to provide the monotonic loading onto the reconstituted soil specimens. All tested soils were subjected to isotropic consolidation and sheared under undrained condition until critical state was ascertain. Based on the results of 32 test specimens, the critical state lines for eight different sand matrix soils were developed together with the corresponding values of critical state parameters, M, ?, and ?. The range of the value of M, ?, and ? is 0.803-0.998, 0.144-0.248, and 1.727-2.279, respectively. These values are comparable to the critical state parameters of river sand and kaolin clay. However, the relationship between fines percentages and these critical state parameters is too scattered to be correlated. PMID:24757417

Marto, Aminaton; Tan, Choy Soon; Makhtar, Ahmad Mahir; Kung Leong, Tiong

2014-01-01

436

IMPROVING SANDSTONE MATRIX STIMULATION OF OIL  

E-print Network

, Dhahran, Saudi Arabia ABSTRACT Experience has shown that for sandstone formations, oil wells respond to matrix acidizing in a different manner as compared to gas wells. For oil wells, the improvement be improved by displacing the oil in the zone to be treated with gas. Gas injection prior to acid- izing

Abu-Khamsin, Sidqi

437

Nonnegative Matrix Factorization for Spectral Data Analysis  

E-print Network

, and asteroids, in orbit around the earth. In this paper we develop an effective nonnegative matrix factorization mining, space object identification and classification. 1 Introduction We are concerned with methods for linear algebraists. It has been shown to be an especially effective tool in several areas of data mining

Plemmons, Robert J.

438

Asymmetric Twin Representation: the Transfer Matrix Symmetry  

E-print Network

The symmetry of the Hamiltonian describing the asymmetric twin model was partially studied in earlier works, and our aim here is to generalize these results for the open transfer matrix. In this spirit we first prove, that the so called boundary quantum algebra provides a symmetry for any generic -- independent of the choice of model -- open transfer matrix with a trivial left boundary. In addition it is shown that the boundary quantum algebra is the centralizer of the $B$ type Hecke algebra. We then focus on the asymmetric twin representation of the boundary Temperley-Lieb algebra. More precisely, by exploiting exchange relations dictated by the reflection equation we show that the transfer matrix with trivial boundary conditions enjoys the recognized ${\\cal U}_{q}(sl_2) \\otimes {\\cal U}_{{\\mathrm i}}(sl_2)$ symmetry. When a non-diagonal boundary is implemented the symmetry as expected is reduced, however again certain familiar boundary non-local charges turn out to commute with the corresponding transfer matrix.

Anastasia Doikou

2007-01-10

439

Matrix Computations: Factorizing in Parallel and  

E-print Network

improves our understand­ ing of the ``nearness'' problems. The closure hierarchy of the orbits (manifolds conditions on perturbations for transiting from the orbit of one KCF to another in the closure hierarchy and orthogonal bases for the normal space to the orbits of strictly equivalent matrix pencils. The deformations

Elmroth, Erik

440

Determination of Matrix Diffusion Properties of Granite  

SciTech Connect

Rock-core column experiments were introduced to estimate the diffusion and sorption properties of Kuru Grey granite used in block-scale experiments. The objective was to examine the processes causing retention in solute transport through rock fractures, especially matrix diffusion. The objective was also to estimate the importance of retention processes during transport in different scales and flow conditions. Rock-core columns were constructed from cores drilled into the fracture and were placed inside tubes to form flow channels in the 0.5 mm gap between the cores and the tube walls. Tracer experiments were performed using uranin, HTO, {sup 36}Cl, {sup 131}I, {sup 22}Na and {sup 85}Sr at flow rates of 1-50 {mu}L.min{sup -1}. Rock matrix was characterized using {sup 14}C-PMMA method, scanning electron microscopy (SEM), energy dispersive X-ray micro analysis (EDX) and the B.E.T. method. Solute mass flux through a column was modelled by applying the assumption of a linear velocity profile and molecular diffusion. Coupling of the advection and diffusion processes was based on the model of generalised Taylor dispersion in the linear velocity profile. Experiments could be modelled applying a consistent parameterization and transport processes. The results provide evidence that it is possible to investigate matrix diffusion at the laboratory scale. The effects of matrix diffusion were demonstrated on the slightly-sorbing tracer breakthrough curves. Based on scoping calculations matrix diffusion begins to be clearly observable for non-sorbing tracer when the flow rate is 0.1 {mu}L.min{sup -1}. The experimental results presented here cannot be transferred directly to the spatial and temporal scales that prevail in an underground repository. However, the knowledge and understanding of transport and retention processes gained from this study is transferable to different scales from laboratory to in-situ conditions. (authors)

Holtta, Pirkko; Siitari-Kauppi, Marja; Huittinen, Nina [Laboratory of Radiochemistry, P.O. Box 55, University of Helsinki, FI-00014 (Finland); Poteri, Antti [VTT Processes, P.O. Box 1608, VTT, FI-02044 (Finland)

2007-07-01

441

RANDOMNESS of Numbers DEFINITION(QUERY:WHAT? V HOW?) ONLY Via MAXWELL-BOLTZMANN CLASSICAL-Statistics(MBCS) Hot-Plasma VS. Digits-Clumping Log-Law NON-Randomness Inversion ONLY BOSE-EINSTEIN QUANTUM-Statistics(BEQS) .  

NASA Astrophysics Data System (ADS)

RANDOMNESS of Numbers cognitive-semantics DEFINITION VIA Cognition QUERY: WHAT???, NOT HOW?) VS. computer-"science" mindLESS number-crunching (Harrel-Sipser-...) algorithmics Goldreich "PSEUDO-randomness"[Not.AMS(02)] mea-culpa is ONLY via MAXWELL-BOLTZMANN CLASSICAL-STATISTICS(NOT FDQS!!!) "hot-plasma" REPULSION VERSUS Newcomb(1881)-Weyl(1914;1916)-Benford(1938) "NeWBe" logarithmic-law digit-CLUMPING/ CLUSTERING NON-Randomness simple Siegel[AMS Joint.Mtg.(02)-Abs. # 973-60-124] algebraic-inversion to THE QUANTUM and ONLY BEQS preferentially SEQUENTIALLY lower-DIGITS CLUMPING/CLUSTERING with d = 0 BEC, is ONLY VIA Siegel-Baez FUZZYICS=CATEGORYICS (SON OF TRIZ)/"Category-Semantics"(C-S), latter intersection/union of Lawvere(1964)-Siegel(1964)] category-theory (matrix: MORPHISMS V FUNCTORS) "+" cognitive-semantics" (matrix: ANTONYMS V SYNONYMS) yields Siegel-Baez FUZZYICS=CATEGORYICS/C-S tabular list-format matrix truth-table analytics: MBCS RANDOMNESS TRUTH/EMET!!!

Siegel, Z.; Carl-Ludwig Siegel, Edward

2011-03-01

442

2matrix: A utility for indel coding and phylogenetic matrix concatenation1  

PubMed Central

• Premise of the study: Phylogenetic analysis of DNA and amino acid sequences requires the creation of files formatted specifically for each analysis package. Programs currently available cannot simultaneously code inferred insertion/deletion (indel) events in sequence alignments and concatenate data sets. • Methods and Results: A novel Perl script, 2matrix, was created to concatenate matrices of non-molecular characters and/or aligned sequences and to code indels. 2matrix outputs a variety of formats compatible with popular phylogenetic programs. • Conclusions: 2matrix efficiently codes indels and concatenates matrices of sequences and non-molecular data. It is available for free download under a GPL (General Public License) open source license (https://github.com/nrsalinas/2matrix/archive/master.zip). PMID:25202595

Salinas, Nelson R.; Little, Damon P.

2014-01-01

443

Pendulum impact resistance of tungsten fiber/metal matrix composites.  

NASA Technical Reports Server (NTRS)

The impact properties of copper, copper-10 nickel, and a superalloy matrix reinforced with tungsten fibers were studied. In most cases the following increased composite impact strength: increased fiber or matrix toughness, decreased fiber-matrix reaction, increased test temperature, hot working and heat treatment. Notch sensitivity was reduced by increasing fiber or matrix toughness. The effect of fiber content depended on the relative toughness of the fibers and matrix. Above 530 K a 60 volume per cent superalloy matrix composite had a greater impact strength than a turbine blade superalloy, whereas below 530 K a hot worked 56 volume per cent composite had a greater impact strength than the superalloy.

Winsa, E. A.; Petrasek, D. W.

1972-01-01

444

Evaluation of bone matrix and demineralized bone matrix incorporated PLGA matrices for bone repair  

Microsoft Academic Search

The aim of this study was to evaluate the composite matrices prepared using Poly(lactic-co-glycolic acid)- PLGA (85:15) by\\u000a incorporating human bone matrix (BM) powder or demineralized bone matrix (DBM) powder with the weight ratio of polymer: BM\\u000a or DBM (75:25) to apply for bone repair. Murine Bone Marrow Stromal Cell (BMSC) attachment was studied with different time\\u000a points at 30 min,

A. Champa Jayasuriya; Nabil A. Ebraheim

2009-01-01

445

Optimizing Tpetra%3CU%2B2019%3Es sparse matrix-matrix multiplication routine.  

SciTech Connect

Over the course of the last year, a sparse matrix-matrix multiplication routine has been developed for the Tpetra package. This routine is based on the same algorithm that is used in EpetraExt with heavy modifications. Since it achieved a working state, several major optimizations have been made in an effort to speed up the routine. This report will discuss the optimizations made to the routine, its current state, and where future work needs to be done.

Nusbaum, Kurtis Lee

2011-08-01

446

Universality in similarity renormalization group evolved potential matrix elements and T-matrix equivalence  

NASA Astrophysics Data System (ADS)

We examine how the universality of two-nucleon interactions evolved using similarity renormalization group (SRG) transformations correlates with T-matrix equivalence, with the ultimate goal of gaining insight into universality for three-nucleon forces. With sufficient running of the SRG flow equations, the low-energy matrix elements of different realistic potentials evolve to a universal form. Because these potentials are fit to low-energy data, they are (approximately) phase equivalent only up to a certain energy, and we find universality in evolved potentials up to the corresponding momentum. More generally we find universality in local energy regions, reflecting a local decoupling by the SRG. The further requirements for universality in evolved potential matrix elements are explored using two simple alternative potentials. We see evidence that in addition to predicting the same observables, common long-range potentials (i.e., explicit pion physics) is required for universality in the potential matrix elements after SRG flow. In agreement with observations made previously for Vlowk evolution, regions of universal potential matrix elements are restricted to where half-on-shell T-matrix equivalence holds.

Dainton, B.; Furnstahl, R. J.; Perry, R. J.

2014-01-01

447

Endothelial matrix assembly during capillary morphogenesis: insights from chimeric TagRFP-fibronectin matrix.  

PubMed

Biologically relevant, three-dimensional extracellular matrix is an essential component of in vitro vasculogenesis models. WI-38 fibroblasts assemble a 3D matrix that induces endothelial tubulogenesis, but this model is challenged by fibroblast senescence and the inability to distinguish endothelial cell-derived matrix from matrix made by WI-38 fibroblasts. Matrices produced by hTERT-immortalized WI-38 recapitulated those produced by wild type fibroblasts. ECM fibrils were heavily populated by tenascin-C, fibronectin, and type VI collagen. Nearly half of the total type I collagen, but only a small fraction of the type IV collagen, were incorporated into ECM. Stable hTERT-WI-38 transfectants expressing TagRFP-fibronectin incorporated TagRFP into ~90% of the fibronectin in 3D matrices. TagRFP-fibronectin colocalized with tenascin-C and with type I collagen in a pattern that was similar to that seen in matrices from wild type WI-38. Human Umbilical Vein Endothelial Cells (HUVEC) formed 3D adhesions and tubes on WI38-hTERT-TagRFP-FN-derived matrices, and the TagRFP-fibronectin component of this new 3D human fibroblast matrix model facilitated the demonstration of concentrated membrane type 1 metalloprotease and new HUVEC FN and collagen type IV fibrils during EC tubulogenesis. These findings indicate that WI-38-hTERT- and WI-38-hTERT-TagRFP-FN-derived matrices provide platforms for the definition of new matrix assembly and remodeling events during vasculogenesis. PMID:25063001

Chang, Fumin; Lemmon, Christopher A; Nilaratanakul, Voraphoj; Rotter, Varda; Romer, Lewis

2014-11-01

448

Transverse fracture and fiber/matrix interface characteristics of hybrid ceramic matrix composites  

NASA Astrophysics Data System (ADS)

Ceramic Matrix Composites (CMCs) represent an attractive class of engineering materials for use in high temperature, high wear and corrosive environments. Much effort has been made to ascertain and improve the strength and fracture characteristics of these materials. Approaches that have received a significant amount of attention include enhancing a ceramic material's mechanical properties through the use of continuous fiber reinforcement; fine, randomly dispersed discontinuous fiber (or whisker) reinforcement; and a hybrid combination of both continuous and discontinuous fibers. This dissertation addresses two important aspects of determining and improving the strength and toughness of CMCs and is comprised of three research papers that have been prepared for journal publication. The first paper, "Transverse Fracture Toughness of Unidirectional Continuous Fiber and Hybrid Ceramic Matrix Composites" provides the results of three-point chevron-notched-beam fracture toughness testing and demonstrates a significant improvement in transverse fracture toughness can be obtained through the use of hybrid fiber reinforcements. The second paper, "A Tensile Testing Method for Ceramic Matrix Composites" presents a novel approach to testing small brittle material specimens using conventional testing equipment with minimal specialized fixture components. The third paper, "Fiber/Matrix Interface Properties of Hybrid Ceramic Matrix Composites", presents a method of determining the characteristics of the fiber/matrix interface of a continuous fiber reinforced CMC and a related hybrid CMC reinforced by both continuous fibers and finely dispersed whiskers using a multiple fiber pullout technique.

Haug, Stephen Berry

449

Matrix-driven formation of mesenchymal stem cell-extracellular matrix microtissues on soft alginate hydrogels.  

PubMed

Mesenchymal stem cells (MSCs) can be made to rearrange into microtissues in response to specific matrix cues, a process that depends on a balance between cell-matrix and cell-cell interactions. The effect of such cues, and especially their interplay, is still not fully understood, particularly in three-dimensional (3-D) systems. Here, the behaviour of human MSCs cultured within hydrogel matrices with tailored stiffness and composition was evaluated. MSC aggregation occurred only in more compliant matrices (G'? 120 Pa), when compared to stiffer ones, both in the presence and in the absence of matrix-bound arginine-glycine-aspartic acid cell-adhesion ligands (RGD; 0, 100 and 200 ?M). Fibronectin assembly stabilized cell-cell contacts within aggregates, even in non-adhesive matrices. However, MSCs were able to substantially contract the artificial matrix only when RGD was present. Moreover, compliant matrices facilitated cell proliferation and provided an environment conducive for MSC osteogenic differentiation, even without RGD. Cell interactions with the original matrix became less important as time progressed, while the de novo-produced extracellular matrix became a more critical determinant of cell fate. These data provide further insights into the mechanisms by which MSCs sense their microenvironment to organize into tissues, and provide new clues to the design of cell-instructive 3-D matrices. PMID:24607421

Maia, F Raquel; Fonseca, Keila B; Rodrigues, Gabriela; Granja, Pedro L; Barrias, Cristina C

2014-07-01

450

Matrix proteases in mitochondrial DNA function.  

PubMed

Lon, ClpXP and m-AAA are the three major ATP-dependent proteases in the mitochondrial matrix. All three are involved in general quality control by degrading damaged or abnormal proteins. In addition to this role, they are proposed to serve roles in mitochondrial DNA functions including packaging and stability, replication, transcription and translation. In particular, Lon has been implicated in mtDNA metabolism in yeast, fly and humans. Here, we review the role of Lon protease in mitochondrial DNA functions, and discuss a putative physiological role for mitochondrial transcription factor A (TFAM) degradation by Lon protease. We also discuss the possible roles of m-AAA and ClpXP in mitochondrial DNA functions, and the putative candidate substrates for the three matrix proteases. This article is part of a Special Issue entitled: Mitochondrial Gene Expression. PMID:22172992

Matsushima, Yuichi; Kaguni, Laurie S

2012-01-01

451

Primitive ultrafine matrix in ordinary chondrites  

NASA Technical Reports Server (NTRS)

Ultrafine matrix material has been concentrated by sieving and filtering disaggregated samples of six ordinary chondrites of different classes. This component(s), 'Holy Smoke' (HS), is enriched in both volatile, e.g. Na, K, Zn, Sb, and Pb, as well as refractory elements, e.g. W and REE; however, the element ratios vary greatly among the different chondrites. SEM studies show that HS contains fragile crystals, differing in composition, and apparently in gross disequilibrium not only among themselves but also with the major mineral phases and consequently thermodynamic equilibration did not occur. Thus HS must have originated from impacting bodies and/or was inherent in the 'primitive' regolith. Subsequent impact brecciation and reheating appears to have altered, to varying degrees, the original composition of this ultrafine matrix material. Recent 'cosmic dust' studies may indicate that HS still exists in the solar system. Survival of such delicate material must be considered in all theories for the origin of chondrites.

Rambaldi, E. R.; Fredriksson, B. J.; Fredriksson, K.

1981-01-01

452

Quantitative matrix assisted plasma desorption mass spectrometry  

NASA Astrophysics Data System (ADS)

The development of optimized sample preparation methods accompanied the history of successful applications of 252Cf-PDMS. Studying the pharmacokinetics of the antineoplastic agent etoposide serum samples from cancer patients were labelled with the homologeous compounds teniposide as internal standard for the quantitative PDMS analysis. Sample purification by chloroform extraction and by thin layer chromatography turned out to be insufficient to guarantee a satisfying final PDMS result. Embedding the purified sample into a matrix of suitable substances on the target reduced the negative influence of impurities, raised the signal-to-noise ratio of molecular ions and improved the reproducibility of calibration. This preparation method was again successfully employed for the quantitative analysis of the cytostatic drug doxorubicin. The application of a different matrix optimized for the preparation of this anthracycline and its homologeous compound daunorubicin, improved the sensitivity, linearity and detection limit.

Jungclas, Hartmut; Schmidt, Lothar; Köhl, Peter; Fritsch, Hans-Walter

1993-07-01

453

Random matrix theory for underwater sound propagation  

E-print Network

Ocean acoustic propagation can be formulated as a wave guide with a weakly random medium generating multiple scattering. Twenty years ago, this was recognized as a quantum chaos problem, and yet random matrix theory, one pillar of quantum or wave chaos studies, has never been introduced into the subject. The modes of the wave guide provide a representation for the propagation, which in the parabolic approximation is unitary. Scattering induced by the ocean's internal waves leads to a power-law random banded unitary matrix ensemble for long-range deep ocean acoustic propagation. The ensemble has similarities, but differs, from those introduced for studying the Anderson metal-insulator transition. The resulting long-range propagation ensemble statistics agree well with those of full wave propagation using the parabolic equation.

Katherine C. Hegewisch; Steven Tomsovic

2011-05-13

454

Google matrix analysis of directed networks  

E-print Network

In past ten years, modern societies developed enormous communication and social networks. Their classification and information retrieval processing become a formidable task for the society. Due to the rapid growth of World Wide Web, social and communication networks, new mathematical methods have been invented to characterize the properties of these networks on a more detailed and precise level. Various search engines are essentially using such methods. It is highly important to develop new tools to classify and rank enormous amount of network information in a way adapted to internal network structures and characteristics. This review describes the Google matrix analysis of directed complex networks demonstrating its efficiency on various examples including World Wide Web, Wikipedia, software architecture, world trade, social and citation networks, brain neural networks, DNA sequences and Ulam networks. The analytical and numerical matrix methods used in this analysis originate from the fields of Markov chain...

Ermann, Leonardo; Shepelyansky, Dima L

2014-01-01

455

Prediction of thermal cycling induced matrix cracking  

NASA Technical Reports Server (NTRS)

Thermal fatigue has been observed to cause matrix cracking in laminated composite materials. A method is presented to predict transverse matrix cracks in composite laminates subjected to cyclic thermal load. Shear lag stress approximations and a simple energy-based fracture criteria are used to predict crack densities as a function of temperature. Prediction of crack densities as a function of thermal cycling is accomplished by assuming that fatigue degrades the material's inherent resistance to cracking. The method is implemented as a computer program. A simple experiment provides data on progressive cracking of a laminate with decreasing temperature. Existing data on thermal fatigue is also used. Correlations of the analytical predictions to the data are very good. A parametric study using the analytical method is presented which provides insight into material behavior under cyclical thermal loads.

Mcmanus, Hugh L.

1992-01-01

456

The Extracellular Matrix: Not Just Pretty Fibrils  

NSDL National Science Digital Library

The extracellular matrix (ECM) and ECM proteins are important in phenomena as diverse as developmental patterning, stem cell niches, cancer, and genetic diseases. The ECM has many effects beyond providing structural support. ECM proteins typically include multiple, independently folded domains whose sequences and arrangement are highly conserved. Some of these domains bind adhesion receptors such as integrins that mediate cell-matrix adhesion and also transduce signals into cells. However, ECM proteins also bind soluble growth factors and regulate their distribution, activation, and presentation to cells. As organized, solid-phase ligands, ECM proteins can integrate complex, multivalent signals to cells in a spatially patterned and regulated fashion. These properties need to be incorporated into considerations of the functions of the ECM.

Richard Hynes (Massachusetts Institute of Technology; Howard Hughes Medical Institute, David H. Koch Institute for Integrative Cancer Research)

2009-11-27

457

Influence of Binder in Iron Matrix Composites  

NASA Astrophysics Data System (ADS)

The ability to use iron and its alloys as the matrix material in composite systems is of great importance because it is the most widely used metallic material with a variety of commercially available steel grades [1]. The aim of this study is to investigate the influence of binder in particulate iron based metal matrix composites. There are four types of binder that were used in this study; Stearic Acid, Gummi Arabisch, Polyvinyl alcohol 15000 MW and Polyvinyl alcohol 22000 MW. Six different weight percentage of each binder was prepared to produce the composite materials using powder metallurgy (P/M) route; consists of dry mixing, uniaxially compacting at 750 MPa and vacuum sintering at 1100° C for two hours. Their characterization included a study of density, porosity, hardness and microstructure. Results indicate that MMC was affected by the binder and stearic acid as a binder produced better properties of the composite.

Shamsuddin, S.; Jamaludin, S. B.; Hussain, Z.; Ahmad, Z. A.

2010-03-01

458

Graphite matrix materials for nuclear waste isolation  

NASA Astrophysics Data System (ADS)

Manufacturing processes are reviewed herein, with primary emphasis on those processes which might be used to produce a graphic matrix for the waste forms. The approach involves the low temperature compaction of a finely ground powder produced from graphitized petroleum coke. The resultant compacts should have fairly good strength, low permeability to both liquids and gases, and anisotropic physical properties. In particular, the anisotropy of the thermal expansion coefficients and the thermal conductivity should be advantageous for this application. With two possible exceptions, the graphite matrix appears to be superior t the metal alloy matrices which have been recommended in prior studies. The two possible exceptions are the requirements on strength and permeability; both requirements will be strongly influenced by the containment design, including the choice of materials and the waste form, of the multibarrier package.

Morgan, W. C.

1981-06-01

459

Visualization of a stock market correlation matrix  

NASA Astrophysics Data System (ADS)

This paper presents a novel application of Neighbor-Net, a clustering algorithm developed for constructing a phylogenetic network in the field of evolutionary biology, to visualizing a correlation matrix. We apply Neighbor-Net as implemented in the SplitsTree software package to 48 stocks listed on the New Zealand Stock Exchange. We show that by visualizing the correlation matrix using a Neighbor-Net splits graph and its associated circular ordering of the stocks that some of the problems associated with understanding the large number of correlations between the individual stocks can be overcome. We compare the visualization of Neighbor-Net with that provided by hierarchical clustering trees and minimum spanning trees. The use of Neighbor-Net networks, or splits graphs, yields greater insight into how closely individual stocks are related to each other in terms of their correlations and suggests new avenues of research into how to construct small diversified stock portfolios.

Rea, Alethea; Rea, William

2014-04-01

460

A Random Matrix Approach to Language Acquisition  

E-print Network

Since language is tied to cognition, we expect the linguistic structures to reflect patterns we encounter in nature and analyzed by physics. Within this realm we investigate the process of protolanguage acquisition, using analytical and tractable methods developed within physics. A protolanguage is a mapping between sounds and objects (or concepts) of the perceived world. This mapping is represented by a matrix and the linguistic interaction among individuals is described by a random matrix model. There are two essential parameters in our approach. The strength of the linguistic interaction $\\beta$, which following Chomsky's tradition, we consider as a genetically determined ability, and the number $N$ of employed sounds (the lexicon size). Our model of linguistic interaction is analytically studied using methods of statistical physics and simulated by Monte Carlo techniques. The analysis reveals an intricate relationship between the innate propensity for language acquisition $\\beta$ and the lexicon size $N$,...

Nicolaidis, A; Argyrakis, Panos

2009-01-01

461

Matrix transformations for spacecraft attitude determination  

NASA Technical Reports Server (NTRS)

A common problem for experimental space physicists is the determination of the attitude matrix T which transforms vectors between representations in X and X' coordinate systems according to (vector V sub X) = (T sub XX')(vector V sub X'). A straightforward, simple, and efficient solution for the transformation matrix is a double-cross transformation. It is calculated from any two directions A and B, which are vectors normalized to unit length and are known in both X and X' coordinates. The B direction need be known only well enough to define the plane in which vectors A and B lie. The problem of the intersection of two cones as applicable to attitude solutions is also discussed.

Cauffman, D. P.

1972-01-01

462

Infrared Mueller matrix acquisition and preprocessing system.  

PubMed

An analog Mueller matrix acquisition and preprocessing system (AMMS) was developed for a photopolarimetric-based sensor with 9.1-12.0 microm optical bandwidth, which is the middle infrared wavelength-tunable region of sensor transmitter and "fingerprint" spectral band for chemical-biological (analyte) standoff detection. AMMS facilitates delivery of two alternate polarization-modulated CO(2) laser beams onto subject analyte that excite/relax molecular vibrational resonance in its analytic mass, primes the photoelastic-modulation engine of the sensor, establishes optimum throughput radiance per backscattering cross section, acquires Mueller elements modulo two laser beams in hexadecimal format, preprocesses (normalize, subtract, filter) these data, and formats the results into digitized identification metrics. Feed forwarding of formatted Mueller matrix metrics through an optimally trained and validated neural network provides pattern recognition and type classification of interrogated analyte. PMID:18806864

Carrieri, Arthur H; Owens, David J; Schultz, Jonathan C

2008-09-20

463

Luneburg lens and optical matrix algebra research  

NASA Technical Reports Server (NTRS)

Planar, as opposed to channelized, integrated optical circuits (IOCs) were stressed as the basis for computational devices. Both fully-parallel and systolic architectures are considered and the tradeoffs between the two device types are discussed. The Kalman filter approach is a most important computational method for many NASA problems. This approach to deriving a best-fit estimate for the state vector describing a large system leads to matrix sizes which are beyond the predicted capacities of planar IOCs. This problem is overcome by matrix partitioning, and several architectures for accomplishing this are described. The Luneburg lens work has involved development of lens design techniques, design of mask arrangements for producing lenses of desired shape, investigation of optical and chemical properties of arsenic trisulfide films, deposition of lenses both by thermal evaporation and by RF sputtering, optical testing of these lenses, modification of lens properties through ultraviolet irradiation, and comparison of measured lens properties with those expected from ray trace analyses.

Wood, V. E.; Busch, J. R.; Verber, C. M.; Caulfield, H. J.

1984-01-01

464

Extracellular Matrix Roles During Cardiac Repair  

PubMed Central

The cardiac extracellular matrix (ECM) provides a platform for cells to maintain structure and function, which in turn maintains tissue function. In response to injury, the ECM undergoes remodeling that involves synthesis, incorporation, and degradation of matrix proteins, with the net outcome determined by the balance of these processes. The major goals of this review are a) to serve as an initial resource for students and investigators new to the cardiac ECM remodeling field, and b) to highlight a few of the key exciting avenues and methodologies that have recently been explored. While we focus on cardiac injury and responses of the left ventricle (LV), the mechanisms reviewed here have pathways in common with other wound healing models. PMID:20670633

Jourdan-LeSaux, Claude; Zhang, Jianhua; Lindsey, Merry L.

2010-01-01

465

Fetal hypoxia and programming of matrix metalloproteinases  

PubMed Central

Fetal hypoxia adversely affects the brain and heart development, yet the mechanisms responsible remain elusive. Recent studies indicate an important role of the extracellular matrix in fetal development and tissue remodeling. The matrix metalloproteinases (MMPs) and their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs) have been implicated in a variety of physiological and pathological processes in the cardiovascular and central nervous systems. This review summarizes current knowledge of the mechanisms by which fetal hypoxia induces the imbalance of MMPs, TIMPs and collagen expression patterns, resulting in growth restriction and aberrant tissue remodeling in the developing heart and brain. Collectively, this information could lead to the development of preventive diagnoses and therapeutic strategies in the fetal programming of cardiovascular and neurological disorders. PMID:21946060

Tong, Wenni; Zhang, Lubo

2011-01-01

466

Rolling Element Bearing Stiffness Matrix Determination (Presentation)  

SciTech Connect

Current theoretical bearing models differ in their stiffness estimates because of different model assumptions. In this study, a finite element/contact mechanics model is developed for rolling element bearings with the focus of obtaining accurate bearing stiffness for a wide range of bearing types and parameters. A combined surface integral and finite element method is used to solve for the contact mechanics between the rolling elements and races. This model captures the time-dependent characteristics of the bearing contact due to the orbital motion of the rolling elements. A numerical method is developed to determine the full bearing stiffness matrix corresponding to two radial, one axial, and two angular coordinates; the rotation about the shaft axis is free by design. This proposed stiffness determination method is validated against experiments in the literature and compared to existing analytical models and widely used advanced computational methods. The fully-populated stiffness matrix demonstrates the coupling between bearing radial, axial, and tilting bearing deflections.

Guo, Y.; Parker, R.

2014-01-01

467

Fermi matrix element with isospin breaking  

E-print Network

Prompted by the level of accuracy now being achieved in tests of the unitarity of the CKM matrix, we consider the possible modification of the Fermi matrix element for the $\\beta$-decay of a neutron, including possible in-medium and isospin violating corrections. While the nuclear modifications lead to very small corrections once the Behrends-Sirlin-Ademollo-Gatto theorem is respected, the effect of the $u-d$ mass difference on the conclusion concerning $V_{ud}$ is no longer insignificant. Indeed, we suggest that the correction to the value of $|V_{ud}|^2 \\, + \\, |V_{us}|^2 \\, + \\, |V_{ub}|^2$ is at the level of $10^{-4}$.

P. A. M. Guichon; A. W. Thomas; K. Saito

2011-01-12

468

Automation of the matrix element reweighting method  

E-print Network

Matrix element reweighting is a powerful experimental technique widely employed to maximize the amount of information that can be extracted from a collider data set. We present a procedure that allows to automatically evaluate the weights for any process of interest in the standard model and beyond. Given the initial, intermediate and final state particles, and the transfer functions for the final physics objects, such as leptons, jets, missing transverse energy, our algorithm creates a phase-space mapping designed to efficiently perform the integration of the squared matrix element and the transfer functions. The implementation builds up on MadGraph, it is completely automatized and publicly available. A few sample applications are presented that show the capabilities of the code and illustrate the possibilities for new studies that such an approach opens up.

P. Artoisenet; V. Lemaître; F. Maltoni; O. Mattelaer

2011-02-01

469

Social patterns revealed through random matrix theory  

NASA Astrophysics Data System (ADS)

Despite the tremendous advancements in the field of network theory, very few studies have taken weights in the interactions into consideration that emerge naturally in all real-world systems. Using random matrix analysis of a weighted social network, we demonstrate the profound impact of weights in interactions on emerging structural properties. The analysis reveals that randomness existing in particular time frame affects the decisions of individuals rendering them more freedom of choice in situations of financial security. While the structural organization of networks remains the same throughout all datasets, random matrix theory provides insight into the interaction pattern of individuals of the society in situations of crisis. It has also been contemplated that individual accountability in terms of weighted interactions remains as a key to success unless segregation of tasks comes into play.

Sarkar, Camellia; Jalan, Sarika

2014-11-01

470

Influence of Binder in Iron Matrix Composites  

SciTech Connect

The ability to use iron and its alloys as the matrix material in composite systems is of great importance because it is the most widely used metallic material with a variety of commercially available steel grades [1]. The aim of this study is to investigate the influence of binder in particulate iron based metal matrix composites. There are four types of binder that were used in this study; Stearic Acid, Gummi Arabisch, Polyvinyl alcohol 15000 MW and Polyvinyl alcohol 22000 MW. Six different weight percentage of each binder was prepared to produce the composite materials using powder metallurgy (P/M) route; consists of dry mixing, uniaxially compacting at 750 MPa and vacuum sintering at 1100 deg. C for two hours. Their characterization included a study of density, porosity, hardness and microstructure. Results indicate that MMC was affected by the binder and stearic acid as a binder produced better properties of the composite.

Shamsuddin, S. [Faculty of Applied Science, Universiti Teknologi MARA, 02600 Arau, Perlis (Malaysia); Jamaludin, S. B. [School of Materials Engineering, Universiti Malaysia Perlis, 02600 Jejawi, Arau, Perlis (Malaysia); Hussain, Z.; Ahmad, Z. A. [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Seri Ampangan, 14300 Nibong Tebal, Seberang Prai Selatan, Pulau Pinang, Malaysi (Malaysia)

2010-03-11

471

Matrix product states for gauge field theories.  

PubMed

The matrix product state formalism is used to simulate Hamiltonian lattice gauge theories. To this end, we define matrix product state manifolds which are manifestly gauge invariant. As an application, we study (1+1)-dimensional one flavor quantum electrodynamics, also known as the massive Schwinger model, and are able to determine very accurately the ground-state properties and elementary one-particle excitations in the continuum limit. In particular, a novel particle excitation in the form of a heavy vector boson is uncovered, compatible with the strong coupling expansion in the continuum. We also study full quantum nonequilibrium dynamics by simulating the real-time evolution of the system induced by a quench in the form of a uniform background electric field. PMID:25215973

Buyens, Boye; Haegeman, Jutho; Van Acoleyen, Karel; Verschelde, Henri; Verstraete, Frank

2014-08-29

472

Ceramic fiber ceramic matrix filter development  

SciTech Connect

The objectives of this project were to develop a novel type of candle filter based on a ceramic fiber-ceramic matrix composite material, and to extend the development to full-size, 60-mm OD by 1-meter-long candle filters. The goal is to develop a ceramic filter suitable for use in a variety of fossil energy system environments such as integrated coal gasification combined cycles (IGCC), pressurized fluidized-bed combustion (PFBC), and other advanced coal combustion environments. Further, the ceramic fiber ceramic matrix composite filter, hereinafter referred to as the ceramic composite filter, was to be inherently crack resistant, a property not found in conventional monolithic ceramic candle filters, such as those fabricated from clay-bonded silicon carbide. Finally, the adequacy of the filters in the fossil energy system environments is to be proven through simulated and in-plant tests.

Judkins, R.R.; Stinton, D.P. [Oak Ridge National Lab., TN (United States); Smith, R.G.; Fischer, E.M. [3M Company, St. Paul, MN (United States)

1994-09-01

473

Matrix control of transforming growth factor-? function  

PubMed Central

The cytokine transforming growth factor-beta (TGF-?) has multiple effects in both physiological and pathological conditions. TGF-? is secreted as part of a tripartite complex from which it must be released in order to bind to its receptor. Sequestration of latent TGF-? in the extracellular matrix (ECM) is crucial for proper mobilization of the latent cytokine and its activation. However, contrary to expectation, loss-of-function mutations in genes encoding certain matrix proteins that bind TGF-? yield elevated, rather than decreased, TGF-? levels, posing a ‘TGF-? paradox.’ In this review, we discuss recent findings concerning the relationship of TGF-?, ECM molecules, and latent TGF-? activation and propose a model to resolve the ‘TGF-? paradox.’ PMID:22923731

Horiguchi, Masahito; Ota, Mitsuhiko; Rifkin, Daniel B.

2012-01-01

474

Parallel matrix multiplication on the Connection Machine  

NASA Technical Reports Server (NTRS)

Matrix multiplication is a computation and communication intensive problem. Six parallel algorithms for matrix multiplication on the Connection Machine are presented and compared with respect to their performance and processor usage. For n by n matrices, the algorithms have theoretical running times of O(n to the 2nd power log n), O(n log n), O(n), and O(log n), and require n, n to the 2nd power, n to the 2nd power, and n to the 3rd power processors, respectively. With careful attention to communication patterns, the theoretically predicted runtimes can indeed be achieved in practice. The parallel algorithms illustrate the tradeoffs between performance, communication cost, and processor usage.

Tichy, Walter F.

1988-01-01

475

Google matrix of business process management  

E-print Network

Development of efficient business process models and determination of their characteristic properties are subject of intense interdisciplinary research. Here, we consider a business process model as a directed graph. Its nodes correspond to the units identified by the modeler and the link direction indicates the causal dependencies between units. It is of primary interest to obtain the stationary flow on such a directed graph, which corresponds to the steady-state of a firm during the business process. Following the ideas developed recently for the World Wide Web, we construct the Google matrix for our business process model and analyze its spectral properties. The importance of nodes is characterized by Page-Rank and recently proposed CheiRank and 2DRank, respectively. The results show that this two-dimensional ranking gives a significant information about the influence and communication properties of business model units. We argue that the Google matrix method, described here, provides a new efficient tool ...

Abel, M

2010-01-01

476

Migration of intradural epidermoid matrix: embryologic implications.  

PubMed

The migratory behavior of acquired cholesteatoma matrices (those arising from the tympanic membrane) has been described previously. This tissue is derived embryologically from the first branchial groove and represents the only migratory epithelium arising from the branchial groove system. If the matrix from a cerebellopontine angle (CPA) epidermoid tumor exhibits migratory behavior similar to that of acquired cholesteatomas, a first branchial groove site of origin for CPA epidermoids would be supported. Intradural CPA epidermoid cells were grown in alpha-minimum essential medium. The cultures were examined daily, and cell mass migration rates were measured. It was observed that intradural epidermoid tumor matrix harvested from the CPA exhibited migration in vitro. Its migratory properties were indistinguishable from those of acquired cholesteatomas, which are embryologically derived from the first branchial groove. These data support the theory that purely intradural epidermoids are derived from cells of the first branchial groove. PMID:10964285

Kountakis, S E; Chang, C Y; Gormley, W B; Cabral, F R

2000-09-01

477

The CKM Matrix and the Unitarity Triangle  

E-print Network

This report contains the results of the Workshop on the CKM Unitarity Triangle, held at CERN on 13-16 February 2002 to study the determination of the CKM matrix from the available data of K, D, and B physics. This is a coherent document with chapters covering the determination of CKM elements from tree level decays and K and B meson mixing and the global fits of the unitarity triangle parameters. The impact of future measurements is also discussed.

M. Battaglia; A. J. Buras; P. Gambino; A. Stocchi; D. Abbaneo; A. Ali; P. Amaral; V. Andreev; M. Artuso; E. Barberio; C. Bauer; D. Becirevic; M. Beneke; I. Bigi; C. Bozzi; T. Brandt; G. Buchalla; M. Calvi; D. Cassel; V. Cirigliano; M. Ciuchini; G. Colangelo; A. Dighe; G. Dubois-Felsmann; G. Eigen; K. Ecklund; P. Faccioli; R. Fleischer; J. Flynn; R. Forty; E. Franco; P. Gagnon; R. Gupta; S. Hashimoto; R. Hawkings; D. Hitlin; A. Hoang; A. Hocker; T. Hurth; G. Isidori

2003-10-15

478

Matrix Acidizing Parallel Core Flooding Apparatus  

E-print Network

, back pressure, overburden, fraction collector, bypass, and pressure transducer. Figure 1: Matrix Acidizing Single Core Holder Schematic Nitrogen Tank Key 316 SS Presure Line 316 SS Oil Line Hastelloy Pressure Line Electric Line H i g... Element Hastelloy Valve 316 SS Valve Data Aquisition Brine Accumulator Refill Tank Fluid Heater Back Pressure Regulator Thermo- probe Acid Accumulator Core Holder Pressure Transducer Injection Pump CPU Overburden Pump 11...

Ghosh, Vivek

2013-07-23

479

Processable polyimide adhesive and matrix composite resin  

NASA Technical Reports Server (NTRS)

A high temperature polyimide composition prepared by reacting 4,4'-isophthaloyldiphthalic anhydride with metaphenylenediamine is employed to prepare matrix resins, adhesives, films, coatings, moldings, and laminates, especially those showing enhanced flow with retention of mechanical and adhesive properties. It can be used in the aerospace industry, for example, in joining metals to metals or metals to composite structures. One area of application is in the manufacture of lighter and stronger aircraft and spacecraft structures.

Pratt, J. Richard (inventor); St.clair, Terry L. (inventor); Progar, Donald J. (inventor)

1990-01-01

480

An optoelectronic switching matrix with high isolation  

Microsoft Academic Search

A high-isolation (60 dB) 10×10 optoelectronic switch matrix with surface-depleted photoconductive crosspoints is reported. The device is designed for a bandwidth greater than 1 GHz and an isolation level greater than 60 dB. Ten 1.8-GHz channels are supported with 0-dB insertion loss and >125 dB\\/Hz dynamic range. The novel crosspoints require reliability improvement because they are unstable

M. Veilleux; R. Ian MacDonald

1992-01-01

481

Extracellular matrix production of lens epithelial cells  

Microsoft Academic Search

Purpose: To examine extracellular matrix (ECM) production of lens epithelial cells (LECs) and their regulation by cytokines.Setting: Research Laboratory, International Intraocular Implant Training Center, Tianjin Medical University, People’s Republic of China.Methods: Bovine LECs were cultured with or without tumor necrosis factor ? (TNF-?) and transforming growth factor ?2 (TGF-?2). Immunohistochemistry and in situ hybridization were used to detect the expression

Xiao-Hong Zhang; Hui-Min Sun; Jia-Qin Yuan

2001-01-01

482

Low-power SXGA active matrix OLED  

Microsoft Academic Search

This paper presents the design and first evaluation of a full-color 1280×3×1024 pixel, active matrix organic light emitting diode (AMOLED) microdisplay that operates at a low power of 200mW under typical operating conditions of 35fL, and offers a precision 30-bit RGB digital interface in a compact size (0.78-inch diagonal active area). The new system architecture developed by eMagin for the

Ihor Wacyk; Olivier Prache; Amal Ghosh

2009-01-01

483

Metal matrix composite structural panel construction  

NASA Technical Reports Server (NTRS)

Lightweight capped honeycomb stiffeners for use in fabricating metal or metal/matrix exterior structural panels on aerospace type vehicles and the process for fabricating same are disclosed. The stiffener stringers are formed in sheets, cut to the desired width and length and brazed in spaced relationship to a skin with the honeycomb material serving directly as the required lightweight stiffeners and not requiring separate metal encasement for the exposed honeycomb cells.

Mcwithey, R. R.; Royster, D. M. (inventors); Bales, T. T.

1983-01-01

484

Nanophosphor composite scintillators comprising a polymer matrix  

DOEpatents

An improved nanophosphor composite comprises surface modified nanophosphor particles in a solid matrix. The nanophosphor particle surface is modified with an organic ligand, or by covalently bonding a polymeric or polymeric precursor material. The surface modified nanophosphor particle is essentially charge neutral, thereby preventing agglomeration of the nanophosphor particles during formation of the composite material. The improved nanophosphor composite may be used in any conventional scintillator application, including in a radiation detector.

Muenchausen, Ross Edward (Los Alamos, NM); Mckigney, Edward Allen (Los Alamos, NM); Gilbertson, Robert David (Los Alamos, NM)

2010-11-16

485

Ceramic Matrix Composites for Rotorcraft Engines  

NASA Technical Reports Server (NTRS)

Ceramic matrix composite (CMC) components are being developed for turbine engine applications. Compared to metallic components, the CMC components offer benefits of higher temperature capability and less cooling requirements which correlates to improved efficiency and reduced emissions. This presentation discusses a technology develop effort for overcoming challenges in fabricating a CMC vane for the high pressure turbine. The areas of technology development include small component fabrication, ceramic joining and integration, material and component testing and characterization, and design and analysis of concept components.

Halbig, Michael C.

2011-01-01

486

Matrix-free interior point method  

Microsoft Academic Search

In this paper we present a redesign of a linear algebra kernel of an interior point method to avoid the explicit use of problem\\u000a matrices. The only access to the original problem data needed are the matrix-vector multiplications with the Hessian and Jacobian\\u000a matrices. Such a redesign requires the use of suitably preconditioned iterative methods and imposes restrictions on the

Jacek Gondzio

2012-01-01

487

Sparse Matrix-Vector multiplication on FPGAs  

Microsoft Academic Search

Floating-point Sparse Matrix-Vector Multiplication (SpMXV) is a key computational kernel in scientific and engineering applications. The poor data locality of sparse matrices significantly reduces the performance of SpMXV on general-purpose processors, which rely heavily on the cache hierarchy to achieve high performance. The abundant hardware resources on current FPGAs provide new opportunities to improve the performance of SpMXV. In this

Ling Zhuo; Viktor K. Prasanna

2005-01-01

488

A matrix model for the ?-Jacobi ensemble  

NASA Astrophysics Data System (ADS)

This note presents a random matrix model for general (?>0) ?-Jacobi ensembles. This generalizes the well-known MANOVA models for ?=1,2,4 and eliminates the quantization of ? (and other parameters) present in the previously known models. This model is a partial answer to an open problem presented by Dumitriu and Edelman, where they also presented models for the ?-Laguerre and ?-Hermite ensembles.

Lippert, Ross A.

2003-10-01

489

Schwarzschild Black Holes from Matrix Theory  

Microsoft Academic Search

We consider matrix theory compactified on T3 and show that it correctly describes the properties of Schwarzschild black holes in 7+1 dimensions, including the mass-entropy relation, the Hawking temperature, and the physical size, up to numerical factors of order unity. The most economical description involves setting the cutoff N in the discretized light-cone quantization to be of order the black

T. Banks; W. Fischler; I. R. Klebanov; L. Susskind

1998-01-01

490

Nucleon's strange electromagnetic and scalar matrix elements  

NASA Astrophysics Data System (ADS)

Quenched lattice QCD simulations and quenched chiral perturbation theory are used together for this study of strangeness in the nucleon. Dependences of the matrix elements on strange quark mass, valence quark mass and momentum transfer are discussed in both the lattice and chiral frameworks. The combined results of this study are in good agreement with existing experimental data and predictions are made for upcoming experiments. Possible future refinements of the theoretical method are suggested.

Lewis, Randy; Wilcox, W.; Woloshyn, R. M.

2003-01-01

491

Matrix metalloproteinases degrade myelin basic protein  

Microsoft Academic Search

Matrix metalloproteinases (MMPs) are a group of enzymes responsible for the degradation of interstitial connective tissue and basement membrane. The coding sequences for five of the human MMPs, viz. interstitial collagenase, 72 kDa gelatinase, stromelysin-1, matrilysin and 92 kDa gelatinase, were cloned and expressed in Chinese hamster ovary cells, and the proteins purified. The enzymes were compared for their ability

Stephen Chandler; Rachael Coates; Andrew Gearing; Jon Lury; Graham Wells; Elisabeth Bone

1995-01-01

492

Matrix metalloproteinases in tumorigenesis: an evolving paradigm  

Microsoft Academic Search

Proteases are crucial for development, tissue remodeling, and tumorigenesis. Matrix metalloproteinases (MMPs) family, in particular,\\u000a consists of more than 20 members with unique substrates and diverse function. The expression and activity of MMPs in a variety\\u000a of human cancers have been intensively studied. MMPs have well-recognized roles in the late stage of tumor progression, invasion,\\u000a and metastasis. However, increasing evidence

Hui Hua; Minjing Li; Ting Luo; Yancun Yin; Yangfu Jiang

493

Ceramic matrix composites containing carbon nanotubes  

Microsoft Academic Search

Due to the remarkable physical and mechanical properties of individual, perfect carbon nanotubes (CNTs), they are considered\\u000a to be one of the most promising new reinforcements for structural composites. Their impressive electrical and thermal properties\\u000a also suggest opportunities for multifunctional applications. In the context of inorganic matrix composites, researchers have\\u000a particularly focussed on CNTs as toughening elements to overcome the

Johann Cho; Aldo R. Boccaccini; Milo S. P. Shaffer

2009-01-01

494

Plastic matrix composites with continuous fiber reinforcement  

SciTech Connect

Most plastic resins are not suitable for structural applications. Although many resins are extremely tough, most lack strength, stiffness, and deform under load with time. By mixing strong, stiff, fibrous materials into the plastic matrix, a variety of structural composite materials can be formed. The properties of these composites can be tailored by fiber selection, orientation, and other factors to suit specific applications. The advantages and disadvantages of fiberglass, carbon-graphite, aramid (Kevlar 49), and boron fibers are summarized.

NONE

1991-09-19

495

Ceramic Matrix Composite Vane Subelement Burst Testing  

NASA Technical Reports Server (NTRS)

Burst tests were performed on Ceramic Matrix Composite (CMC) vane specimens, manufactured by two vendors, under the Ultra Efficient Engine Technology (UEET) project. Burst specimens were machined from the ends of 76mm long vane sub-elements blanks and from High Pressure Burner Rig (HPBR) tested specimens. The results of burst tests will be used to compare virgin specimens with specimens that have had an Environmental Barrier Coating (EBC) applied, both HPBR tested and untested, as well as a comparison between vendors.

Brewer, David N.; Verrilli, Michael; Calomino, Anthony

2006-01-01

496

MAMSolver: A Matrix Analytic Methods Tool  

Microsoft Academic Search

MAMsolver is a software tool for the solution of M\\/G\\/1type,GI\\/M\\/1-type, and QBD processes. The collection of solution algorithmsimplemented by MAMsolver are known as matrix-analytic methods and are used to compute stationary measures of interest such as theprobability vector, the queue length distribution, the waiting time, thesystem queue length, and any higher moments of the queue length. Thetool also provides probabilistic

Alma Riska; Evgenia Smirni

2002-01-01

497

Constructing gauge theory geometries from matrix models  

Microsoft Academic Search

We use the matrix model - gauge theory correspondence of Dijkgraaf and Vafa in order to construct the geometry encoding the exact gaugino condensate superpotential for the Script N = 1 U(N) gauge theory with adjoint and symmetric or anti-symmetric matter, broken by a tree level superpotential to a product subgroup involving U(Ni) and SO(Ni) or Sp({Ni}\\/2) factors. The relevant

Albrecht Klemm; Karl Landsteiner; Calin Iuliu Lazaroiu; Ingo Runkel

2003-01-01

498

A tough high performance composite matrix  

NASA Technical Reports Server (NTRS)

This invention is a semi-interpenetrating polymer network which includes a high performance thermosetting polyimide having a nadic end group acting as a crosslinking site and a high performance linear thermoplastic polyimide. An improved high temperature matrix resin is provided which is capable of performing in the 200 to 300 C range. This resin has significantly improved toughness and microcracking resistance, excellent processability, mechanical performance and moisture and solvent resistances.

Pater, Ruth H. (inventor); Johnston, Norman J. (inventor)

1992-01-01

499

Matrix elements of the Breit Hamiltonian  

Microsoft Academic Search

A formulation has been developed for the evaluation of the matrix representation, in sets of ||SMSLML), ||SLJMJ), or ||JIFMF) functions (as required), of the complete atomic Hamiltonian operator consisting of the electronic, the SL-nonsplitting (specific mass, mass variation, Darwin, spin-spin contact, and orbit-orbit) correction terms, and the fine- (spin-orbit and spin-spin dipole) and hyperfine-structure (magnetic dipole, electric quadrupole, and magnetic

S. Fraga; M. Klobukowski; J. Muszynska; K. M. S. Saxena; J. A. Sordo

1986-01-01

500

Effective dynamics of the matrix big bang  

Microsoft Academic Search

We study the leading quantum effects in the recently introduced matrix big bang model. This amounts to a study of supersymmetric Yang-Mills theory compactified on the Milne orbifold. We find a one-loop potential that is attractive near the big bang. Surprisingly, the potential decays very rapidly at late times where it appears to be generated by D-brane effects. Usually, general

B. E. L. Craps; Arvind Rajaraman; Savdeep Sethi

2006-01-01