Tribological Behavior of TiAl Matrix Composites with MoO3 Tabular Crystal
NASA Astrophysics Data System (ADS)
Zhang, Ao; Shi, Xiaoliang; Zhai, Wenzheng; Yang, Kang; Wang, Zhihai
2015-11-01
The friction and wear behaviors of TiAl matrix self-lubricating composites (TMSC) with MoO3 tabular crystal (MTC) against GCr15 steel ball are tested using a constant load of 10 N and a constant speed of 0.2 m/s from room temperature to 600 °C. The result shows that, during the sliding friction and wear process, the MTC which has the microstructure of multiple layers could reduce the shear stress, leading to the reduction of friction coefficient. Meanwhile, TMSC with MTC exhibits the excellent tribological performance over a wide temperature range, if compared to TiAl based alloy. Moreover, MTC can improve the tribological properties of TMSC obviously below 400 °C.
NASA Astrophysics Data System (ADS)
Siegel, Carl Ludwig; Siegel, Edward Carl-Ludwig
2011-03-01
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)
A Tabular Expression Toolbox for Matlab/Simulink
Lawford, Mark
with Matlab's simulation and code generation. 1 Introduction Model based design (MBD) has gained increasedA Tabular Expression Toolbox for Matlab/Simulink Colin Eles and Mark Lawford McMaster Centre the Tabular Expression Toolbox for Matlab/Simulink1 . An intuitive user interface allows users to easily
Users' guide for the tabular display report generator program (TABDIS)
NASA Technical Reports Server (NTRS)
Braley, D. M.
1980-01-01
The tabular display report generator (TABDIS) program is described. The program functions as a document generation tool that provides tabular displays of data stored on a data file which has been generated by a user program. The main features of the program are outlined and all necessary inputs are detailed.
A new model for tabular-type uranium deposits
Sanford, R.F.
1992-01-01
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
BayesDB : querying the probable implications of tabular data
Baxter, Jay
2014-01-01
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 ...
Network-Based Visual Analysis of Tabular Data
ERIC Educational Resources Information Center
Liu, Zhicheng
2012-01-01
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…
Min-cut segmentation of cursive handwriting in tabular documents
NASA Astrophysics Data System (ADS)
Davis, Brian L.; Barrett, William A.; Swingle, Scott D.
2015-01-01
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.
Horizontal Aggregations for Building Tabular Data Sets Carlos Ordonez
Ordonez, Carlos
Horizontal Aggregations for Building Tabular Data Sets Carlos Ordonez Teradata, NCR San Diego, CA, USA ABSTRACT In a data mining project, a significant portion of time is devoted to building a data set suitable for analysis. In a re- lational database environment, building such data set usu- ally requires
MCNP/X TRANSPORT IN THE TABULAR REGIME
HUGHES, H. GRADY
2007-01-08
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.
Brooks, Robert A.; Campbell, John A.
1976-01-01
Ore in the La Sal mine, San Juan County, Utah, occurs as a typical tabular-type uranium deposit of the-Colorado Plateau. Uranium-vanadium occurs in the Salt Wash Member of the Jurassic Morrison Formation. Chemical and petrographic analyses were used to determine elemental variation and diagenetic aspects across the orebody. Vanadium is concentrated in the dark clay matrix, which constitutes visible ore. Uranium content is greater above the vanadium zone. Calcium, carbonate carbon, and lead show greater than fifty-fold increase across the ore zone, whereas copper and organic carbon show only a several-fold increase. Large molybdenum concentrations are present in and above the tabular layer, and large selenium concentrations occur below the uranium zone within the richest vanadium zone. Iron is enriched in the vanadium horizon. Chromium is depleted from above the ore and strongly enriched below. Elements that vary directly with the vanadium content include magnesium, iron, selenium, zirconium, strontium, titanium, lead, boron, yttrium, and scandium. The diagenetic sequence is as follows: (1) formation of secondary quartz overgrowths as cement; (2) infilling and lining of remaining pores with amber opaline material; (3) formation of vanadium-rich clay matrix, which has replaced overgrowths as well as quartz grains; (4) replacement of overgrowths and detrital grains by calcite; (5) infilling of pores with barite and the introduction of pyrite and marcasite.
Consistent thermodynamic derivative estimates for tabular equations of state.
NASA Astrophysics Data System (ADS)
Dilts, Gary
2005-07-01
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.
Consistent thermodynamic derivative estimates for tabular equations of state
NASA Astrophysics Data System (ADS)
Dilts, Gary A.
2006-06-01
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.
Wind-driven upwelling around grounded tabular icebergs
NASA Astrophysics Data System (ADS)
Stern, Alon A.; Johnson, Eric; Holland, David M.; Wagner, Till J. W.; Wadhams, Peter; Bates, Richard; Abrahamsen, E. Povl; Nicholls, Keith W.; Crawford, Anna; Gagnon, Jonathan; Tremblay, Jean-Eric
2015-08-01
Temperature and salinity data collected around grounded tabular icebergs in Baffin Bay in 2011, 2012, and 2013 indicate wind-induced upwelling at certain locations around the icebergs. These data suggest that along one side of the iceberg, wind forcing leads to Ekman transport away from the iceberg, which causes upwelling of the cool saline water from below. The upwelling water mixes with the water above the thermocline, causing the mixed layer to become cooler and more saline. Along the opposite side of the iceberg, the surface Ekman transport moves towards the iceberg, which causes a sharpening of the thermocline as warm fresh water is trapped near the surface. This results in higher mixed layer temperatures and lower mixed layer salinities on this side of the iceberg. Based on these in situ measurements, we hypothesize that the asymmetries in water properties around the iceberg, caused by the opposing effects of upwelling and sharpening of the thermocline, lead to differential deterioration around the iceberg. Analysis of satellite imagery around iceberg PII-B-1 reveals differential decay around the iceberg, in agreement with this mechanism.
Geosites inventory of the northwestern Tabular Middle Atlas of Morocco
NASA Astrophysics Data System (ADS)
El Wartiti, Mohamed; Malaki, Amina; Zahraoui, Mohamed; El Ghannouchi, Abdelilah; di Gregorio, Felice
2008-07-01
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.
Automated Generation of Tabular Equations of State with Uncertainty Information
NASA Astrophysics Data System (ADS)
Carpenter, John H.; Robinson, Allen C.; Debusschere, Bert J.; Mattsson, Ann E.
2015-06-01
As computational science pushes toward higher fidelity prediction, understanding the uncertainty associated with closure models, such as the equation of state (EOS), has become a key focus. Traditional EOS development often involves a fair amount of art, where expert modelers may appear as magicians, providing what is felt to be the closest possible representation of the truth. Automation of the development process gives a means by which one may demystify the art of EOS, while simultaneously obtaining uncertainty information in a manner that is both quantifiable and reproducible. We describe our progress on the implementation of such a system to provide tabular EOS tables with uncertainty information to hydrocodes. Key challenges include encoding the artistic expert opinion into an algorithmic form and preserving the analytic models and uncertainty information in a manner that is both accurate and computationally efficient. Results are demonstrated on a multi-phase aluminum model. *Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
Consistent thermodynamic derivative estimates for tabular equations of state.
Dilts, Gary A
2006-06-01
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. PMID:16907020
Analyzing Tabular and State-Transition Requirements Specifications in PVS
NASA Technical Reports Server (NTRS)
Owre, Sam; Rushby, John; Shankar, Natarajan
1997-01-01
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.
Code of Federal Regulations, 2012 CFR
2012-01-01
... product to a security interest, on EFS and master list-format. 205.102 Section 205.102 Animals and Animal... of person subjecting a farm product to a security interest, on EFS and master list—format. On an EFS, and on a master list, the name of the person subjecting a farm product to a security interest...
Code of Federal Regulations, 2011 CFR
2011-01-01
... product to a security interest, on EFS and master list-format. 205.102 Section 205.102 Animals and Animal... of person subjecting a farm product to a security interest, on EFS and master list—format. On an EFS, and on a master list, the name of the person subjecting a farm product to a security interest...
Code of Federal Regulations, 2014 CFR
2014-01-01
... product to a security interest, on EFS and master list-format. 205.102 Section 205.102 Animals and Animal... of person subjecting a farm product to a security interest, on EFS and master list—format. On an EFS, and on a master list, the name of the person subjecting a farm product to a security interest...
Code of Federal Regulations, 2010 CFR
2010-01-01
... product to a security interest, on EFS and master list-format. 205.102 Section 205.102 Animals and Animal... of person subjecting a farm product to a security interest, on EFS and master list—format. On an EFS, and on a master list, the name of the person subjecting a farm product to a security interest...
Code of Federal Regulations, 2013 CFR
2013-01-01
... product to a security interest, on EFS and master list-format. 205.102 Section 205.102 Animals and Animal... of person subjecting a farm product to a security interest, on EFS and master list—format. On an EFS, and on a master list, the name of the person subjecting a farm product to a security interest...
NASA Astrophysics Data System (ADS)
Kerry, J. T.; Bellwood, D. R.
2015-06-01
Large reef fishes may often be seen sheltering under tabular structures on coral reefs. There are two principle explanations for this behaviour: avoidance of predation or avoidance of solar irradiance. This study sought supporting evidence to distinguish between these two explanations by examining the usage of tabular structures on a shallow mid-shelf reef of the Great Barrier Reef at midday and sunset. If predation avoidance is most important, usage should increase towards sunset; conversely, if avoidance of solar radiation is most important, more fishes should use cover at midday. Underwater video observations revealed that tabular structures were extensively used by large reef fishes at midday, being characterised by numerous species, especially Lutjanidae and Haemulidae. In contrast, at sunset, tabular structures were used by significantly fewer large reef fishes, being characterised mostly by species of unicornfish ( Naso spp.). Resident times of fishes using tabular structures were also significantly longer at midday (28:06 ± 5:55 min) than at sunset (07:47 ± 2:19 min). The results suggest that the primary function of tabular structures for large reef fishes is the avoidance of solar irradiance. This suggestion is supported by the position of fishes when sheltering. The majority of large reef fishes were found to shelter under the lip of tabular structure, facing outwards. This behaviour is thought to allow protection from harmful downwelling UV-B irradiance while allowing the fish to retain photopic vision and survey more of the surrounding area. These findings help to explain the importance of tabular structures for large reef fishes on coral reefs, potentially providing a valuable energetic refuge from solar irradiance.
Do tabular corals constitute keystone structures for fishes on coral reefs?
NASA Astrophysics Data System (ADS)
Kerry, J. T.; Bellwood, D. R.
2015-03-01
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.
Formation of tabular single-domain magnetite induced by Geobacter metallireducens GS-15
Kirschvink, Joseph L.
Formation of tabular single-domain magnetite induced by Geobacter metallireducens GS-15 Hojatollah.g., an anisotropic medium) has been reported (1, 2). Although magnetite forms predominantly diamond-shape octahedrons is produced intracellularly by a variety of magnetic bacteria in diverse environments (46). The formation
Tracking large tabular icebergs using the SeaWinds Ku-band microwave scatterometer
Long, David G.
Tracking large tabular icebergs using the SeaWinds Ku-band microwave scatterometer K.M. Stuart Ã, D Resolution enhancement Icebergs Sea ice NSF Antarctic cruise a b s t r a c t Knowledge of iceberg locations icebergs scatter microwave energy more than sea ice and sea water, icebergs are detected as high
STING Report: convenient web-based application for graphic and tabular presentations of protein
Neshich, Goran
STING Report: convenient web-based application for graphic and tabular presentations of protein sequence, structure and function descriptors from the STING database Goran Neshich*, Adauto L. Mancini and Accepted October 18, 2004 ABSTRACT The Sting Report is a versatile web-based application for extraction
NASA Astrophysics Data System (ADS)
Schmalz, M.; Ritter, G.; Key, R.
Accurate and computationally efficient spectral signature classification is a crucial step in the nonimaging detection and recognition of spaceborne objects. In classical hyperspectral recognition applications using linear mixing models, signature classification accuracy depends on accurate spectral endmember discrimination [1]. If the endmembers cannot be classified correctly, then the signatures cannot be classified correctly, and object recognition from hyperspectral data will be inaccurate. In practice, the number of endmembers accurately classified often depends linearly on the number of inputs. This can lead to potentially severe classification errors in the presence of noise or densely interleaved signatures. In this paper, we present an comparison of emerging technologies for nonimaging spectral signature classfication based on a highly accurate, efficient search engine called Tabular Nearest Neighbor Encoding (TNE) [3,4] and a neural network technology called Morphological Neural Networks (MNNs) [5]. Based on prior results, TNE can optimize its classifier performance to track input nonergodicities, as well as yield measures of confidence or caution for evaluation of classification results. Unlike neural networks, TNE does not have a hidden intermediate data structure (e.g., the neural net weight matrix). Instead, TNE generates and exploits a user-accessible data structure called the agreement map (AM), which can be manipulated by Boolean logic operations to effect accurate classifier refinement algorithms. The open architecture and programmability of TNE's agreement map processing allows a TNE programmer or user to determine classification accuracy, as well as characterize in detail the signatures for which TNE did not obtain classification matches, and why such mis-matches occurred. In this study, we will compare TNE and MNN based endmember classification, using performance metrics such as probability of correct classification (Pd) and rate of false detections (Rfa). As proof of principle, we analyze classification of multiple closely spaced signatures from a NASA database of space material signatures. Additional analysis pertains to computational complexity and noise sensitivity, which are superior to Bayesian techniques based on classical neural networks. [1] Winter, M.E. "Fast autonomous spectral end-member determination in hyperspectral data," in Proceedings of the 13th International Conference On Applied Geologic Remote Sensing, Vancouver, B.C., Canada, pp. 337-44 (1999). [2] N. Keshava, "A survey of spectral unmixing algorithms," Lincoln Laboratory Journal 14:55-78 (2003). [3] Key, G., M.S. SCHMALZ, F.M. Caimi, and G.X. Ritter. "Performance analysis of tabular nearest neighbor encoding algorithm for joint compression and ATR", in Proceedings SPIE 3814:115-126 (1999). [4] Schmalz, M.S. and G. Key. "Algorithms for hyperspectral signature classification in unresolved object detection using tabular nearest neighbor encoding" in Proceedings of the 2007 AMOS Conference, Maui HI (2007). [5] Ritter, G.X., G. Urcid, and M.S. Schmalz. "Autonomous single-pass endmember approximation using lattice auto-associative memories", Neurocomputing (Elsevier), accepted (June 2008).
Sanford, R.F. )
1990-11-01
Hydrogeologic modeling shows that tabular-type uranium deposits in the grants uranium region of the San Juan basin, New Mexico, formed in zones of ascending and discharging regional ground-water flow. The association of either lacustrine mudstone or actively subsiding structures and uranium deposits can best be explained by the occurrence of lakes at topographic depressions where ground water having different sources and compositions is likely to converge, mix, and discharge. Ascending and discharging flow also explains the association of uranium deposits with underlying evaporites and suggests a brine interface. The simulations contradict previous suggestions that ground water moved downward in the mudflat.
Liu Suwen; Wehmschulte, Rudolf J. . E-mail: rwehmsch@fit.edu; Lian Guoda; Burba, Christopher M.
2006-03-15
Long silver nanowires were synthesized at room temperature by a simple and fast process derived from the development of photographic films. A film consisting of an emulsion of tabular silver bromide grains in gelatin was treated with a photographic developer (4-(methylamino)phenol sulfate (metol), citric acid) in the presence of additional aqueous silver nitrate. The silver nanowires have lengths of more than 50 {mu}m, some even more than 100 {mu}m, and average diameters of about 80 nm. Approximately, 70% of the metallic silver formed in the reduction consists of silver nanowires. Selected area electron diffraction (SAED) results indicate that the silver nanowires grow along the [111] direction. It was found that the presence of gelatin, tabular silver bromide crystals and silver ions in solution are essential for the formation of the silver nanowires. The nanowires appear to originate from the edges of the silver bromide crystals. They were characterized by transmission electron microscopy (TEM), SAED, scanning electron microscopy (SEM), and powder X-ray diffraction (XRD)
A quantitative model of ground-water flow during formation of tabular sandstone uranium deposits
Sanford, R.F.
1994-01-01
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
NASA Technical Reports Server (NTRS)
Zehe, Michael J.; Gordon, Sanford; McBride, Bonnie J.
2002-01-01
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.
A Simple Tool for Integration and Differentiation of Tabular Values in Microsoft Excel
NASA Astrophysics Data System (ADS)
Haugland, Ole Anton
2011-12-01
There are many software alternatives for analyzing experimental data in our physics teaching. I prefer to use Excel® because of its flexibility and widespread use elsewhere in our society. Whatever our students will work with in their future career, they almost certainly will have access to a spreadsheet. For a long time I have missed a tool for integrating and differentiating tabular values in Excel. For every new version I thought it would appear, but it did not. Such a tool could also be useful if you analyze data from other sources than your own experiment, for example, data from the Internet. Therefore, I have written a simple tool that can be integrated seamlessly into Excel as an add-in. It is written in Excels powerful macro language Microsoft Visual Basic for Applications. The tool can be downloaded online and there are two versions of it: one for Excel 2003 and one for Excel 2007/2010.
CAP: A Computer Code for Generating Tabular Thermodynamic Functions from NASA Lewis Coefficients
NASA Technical Reports Server (NTRS)
Zehe, Michael J.; Gordon, Sanford; McBride, Bonnie J.
2001-01-01
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.
Tabular water properties interface for Hydra-TH : CASL THM.CFD.P6.03 milestone report.
Carpenter, John H.; Belcourt, Noel
2013-04-01
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
Effects of Rigid Body Collisions and Tide-Forced Drift on Large Tabular Icebergs of the Antarctic
Macayeal, Douglas R.
1 Effects of Rigid Body Collisions and Tide-Forced Drift on Large Tabular Icebergs of the Antarctic ICEBERGS #12;2 Abstract. Following the calving of an iceberg from an ice shelf, many collisions between the new iceberg and the remaining shelf can occur as the iceberg responds to time-varying oceanic
Tracking large tabular icebergs using the SeaWinds Ku-band microwave scatterometer
NASA Astrophysics Data System (ADS)
Stuart, K. M.; Long, D. G.
2011-06-01
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.
Calcium-doped ceria/titanate tabular functional nanocomposite by layer-by-layer coating method
Liu, Xiang W.; Devaraju, M.K.; Yin, Shu; Sato, Tsugio
2010-07-15
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.
Ambient seismic, hydroacoustic, and flexural gravity wave noise on a tabular iceberg
NASA Astrophysics Data System (ADS)
MacAyeal, Douglas R.; Wang, Yitan; Okal, Emile A.
2015-02-01
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.
The communicability of graphical alternatives to tabular displays of statistical simulation studies.
Cook, Alex R; Teo, Shanice W L
2011-01-01
Simulation studies are often used to assess the frequency properties and optimality of statistical methods. They are typically reported in tables, which may contain hundreds of figures to be contrasted over multiple dimensions. To assess the degree to which these tables are fit for purpose, we performed a randomised cross-over experiment in which statisticians were asked to extract information from (i) such a table sourced from the literature and (ii) a graphical adaptation designed by the authors, and were timed and assessed for accuracy. We developed hierarchical models accounting for differences between individuals of different experience levels (under- and post-graduate), within experience levels, and between different table-graph pairs. In our experiment, information could be extracted quicker and, for less experienced participants, more accurately from graphical presentations than tabular displays. We also performed a literature review to assess the prevalence of hard-to-interpret design features in tables of simulation studies in three popular statistics journals, finding that many are presented innumerately. We recommend simulation studies be presented in graphical form. PMID:22132184
Genesis of the tabular-type vanadium-uranium deposits of the Henry Basin, Utah
Northrop, H.R.; Goldhaber, M.B.
1990-01-01
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
Hazen, T.C.
1993-09-01
This document consists solely of data acquired during phase 2 of the integrated demonstration project concerning in situ bioremediation performed at the Savannah River Site, Aiken, South Carolina. The data is presented in tabular form.
Big-Bang reaction rates within the R-matrix model
NASA Astrophysics Data System (ADS)
Descouvemont, P.; Adahchour, A.; Angulo, C.; Coc, A.; Vangioni-Flam, E.
2005-07-01
We use the R-matrix theory to fit S-factor data on nuclear reactions involved in Big Bang nucleosynthesis. We derive the reaction rates with associated uncertainties, which are evaluated on statistical grounds. We provide S factors and reaction rates in tabular and graphical formats (available at http://pntpm3.ulb.ac.be/bigbang).
Shepelyansky, Dima
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
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
Klett, T.R.; Le, P.A.
2007-01-01
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.
NASA Technical Reports Server (NTRS)
Roddy, D. J.
1977-01-01
A tabular outline of comparative data is presented for 340 basic dimensional, morphological, and structural parameters and related aspects for three craters of the flat-floored, central uplift type, two of which are natural terrestrial impact craters and one is a large-scale experimental explosion crater. The three craters are part of a general class, in terms of their morphology and structural deformation that is represented on each of the terrestrial planets including the moon. One of the considered craters, the Flynn Creek Crater, was formed by a hypervelocity impact event approximately 360 m.y. ago in what is now north central Tennessee. The impacting body appears to have been a carbonaceous chondrite or a cometary mass. The second crater, the Steinheim Crater, was formed by an impact event approximately 14.7 m.y. ago in what is now southwestern Germany. The Snowball Crater was formed by the detonation of a 500-ton TNT hemisphere on flat-lying, unconsolidated alluvium in Alberta, Canada.
NASA Astrophysics Data System (ADS)
Hall, Duncan; Kisters, Alexander
2016-01-01
Granitoid plutons in the deeply eroded south Central Zone of the Damara Belt in Namibia commonly show tabular geometries and pronounced stratigraphic controls on their emplacement. Subhorizontal, sheet-like pluton geometries record emplacement during regional subhorizontal shortening, but the intrusion of spatially and temporally closely-related granitoid plutons at different structural levels and in distinct structural settings suggests independent controls on their levels of emplacement. We describe and evaluate the controls on the loci of the dyke-to-sill transition that initiated the emplacement of three syntectonic (560-530 Ma) plutons in the basement-cover stratigraphy of the Erongo region. Intrusive relationships highlight the significance of (1) rigidity anisotropies associated with competent sedimentary packages or pre-existing subhorizontal granite sheets and (2) rheological anisotropies associated with the presence of thick ductile marble horizons. These mechanical anisotropies may lead to the initial deflection of steep feeder conduits as well as subsequent pluton assembly by the repeated underaccretion of later magma batches. The upward displacement of regional isotherms due to the heat advection associated with granite emplacement is likely to have a profound effect on the mechanical stratification of the upper crust and, consequently, on the level at which granitoid pluton emplacement is initiated. In this way, pluton emplacement at progressively shallower crustal depths may have resulted in the unusually high apparent geothermal gradients recorded in the upper crustal levels of the Damara Belt during its later evolution.
Nikitin, A G
2011-01-01
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 $W=kQ+\\frac1k R+P$ where $k$ is a variable parameter, $Q$ is the unit matrix multiplied by a function of independent variable $x$, and $P$, $R$ are 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.
NASA Astrophysics Data System (ADS)
Nikitin, Anatoly G.; Karadzhov, Yuri
2011-07-01
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.
Last Time: Matrix of Linear Transformation Matrix Algebra Matrix Algebra
Bigelow, Stephen
Last Time: Matrix of Linear Transformation Matrix Algebra Matrix Algebra Math 4A Xianzhe Dai UCSB April 16, 2014 Based on the 2013 Millett and Scharlemann Lectures 1/14 #12;Last Time: Matrix of Linear Transformation Matrix Algebra Last Time:Matrix of Linear Transformation Definition A linear transformation
NASA Technical Reports Server (NTRS)
Stumpff, P.; Lieske, J. H.
1984-01-01
Properties of astronomical time scales (ET and UT) are considered, with particular emphasis on correctly determining of-date longitude as the sum of inertial mean longitude of the sun relative to the mean equinox of a fixed epoch (1950.0), and the general precession in longitude accumulated since the epoch. The inertial mean longitude and motion (relative to the mean equinox) are derived from tabular ephemerides such as the Jet Propulsion Laboratories' DE 102 and DE 96, by comparisons with subroutines based on Newcomb's perturbation theory. An unresolved inconsistency of approximately 1 second per century among the mean inertial motion of DE 102, IAU precession speed (1976), and the classical Newcomb of-date mean motion is found. Interpretation difficulties arising from the use of different systems of Ephemeris Time are also discussed.
Klett, T.R.; Le, P.A.
2006-01-01
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).
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
Matrices 1. Matrix Algebra Matrix algebra.
Culpepper, Martin L.
Matrices 1. Matrix Algebra Matrix algebra. Previously we calculated the determinants of square rows and n columns is called an m Ã? n matrix. The number in the i-th row and j-th column (where 1 i m, 1 j n) is called the ij-entry, and denoted aij; the matrix itself is denoted by A, or sometimes
Launay, G.; Salza, R.; Multedo, D.; Thierry-Mieg, N.; Ricard-Blum, S.
2015-01-01
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
Tabular Privacyy Preserving Publishingg g
Zhang, Jun
Computer Back pain A04 56 F Government 610020 Sports Heart disease A05 47 M Police 610020 Music Neck pain Neck pain Bill 47 M Police 610020 Music Heart disease Explicit Identifier (e.g. name, ID #, Driver 610020 Sports Neck pain Bill 47 M Police 610020 Music Heart disease In the table 1. The value of every
Hybrid matrix fiber composites
Deteresa, Steven J.; Lyon, Richard E.; Groves, Scott E.
2003-07-15
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.
Vickers, James
Matrix norms 30.4 Introduction A matrix norm is a number defined in terms of the entries of the matrix. The norm is a useful quantity which can give important information about a matrix. 9 8 6 7 completing this Section you should be able to . . . calculate norms and condition numbers of small matrices
ERIC Educational Resources Information Center
Digital Equipment Corp., Maynard, MA.
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…
St Andrews, University of
Matrix Groups Max Neunhöffer Introduction GAP examples Matrix groups in GAP Schreier-Sims Problems Group algebras SLPs Constructive recognition The problem Troubles Matrix Groups Max Neunhöffer University of St Andrews GAC 2010, Allahabad #12;Matrix Groups Max Neunhöffer Introduction GAP examples
Algorithms for matrix completion
Xin, Yu, Ph. D. Massachusetts Institute of Technology
2012-01-01
We consider collaborative filtering methods for matrix completion. A typical approach is to find a low rank matrix that matches the observed ratings. However, the corresponding problem has local optima. In this thesis, we ...
NASA Astrophysics Data System (ADS)
Siegel, Edward Plato Aristotle Archimedes Carl-Ludwig; Young, Frederic; Lewis, Thomas
2013-06-01
Siegel[MRS Fall-Mtgs,:Symp.Fractals(89)-5-papers!!!;Symp.Scaling(90)] FCP/CSC {aka SPD}(Tic-Tac-Toe-Matrix/Tabular List-Format) ``COMMON-FUNCTIONING-PRINCIPLE'' DI/TRI-CHOTOMY GENERIC ``INEVITABILITY_-WEB'' PURPOSEFUL PARSIMONY-of-DI/TRI-CHOTOMY STRATEGY REdiscovery of SoO automatically/optimality is in NON-list-format/matrix: DIMENSIONALITY-DOMINATION -INEVIT-ABILITY ROOT-CAUSE(RC) ULTIMATE-ORIGIN(UO): (level-0.-logic) DIMENSIONALITY (level-0. logic): [dst = ODD-Z] <->{Dst=FRACTAL-UNcertainty FLUCTUATIONS} <->(dst = EVEN-Z): CAUSES: (level- I.-logic): EXTENT/SCALE/RADIUS: (relative)-[LOCALITY] <-> (relative)-(...GLOBALITY...) & (level-II.-logic): POWER-SPECTRUM{noise ?generalized-susceptibility}: [``l''/?0-White] <->(...-``l''/? 1 . 000 . . . - HYPERBOLICITY...) & (level-III.-logic) CRITICAL-EXPONENT:n =0 <->n = 1.000... ; BUT ALL 3 ALSO CAUSED BY ANOTHER INdependent RCUO (level-IV.-logic):
Farooque, M.; Yuh, C.Y.
1996-12-03
A carbonate fuel cell matrix is described 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. 8 figs.
Farooque, Mohammad (Huntington, CT); Yuh, Chao-Yi (New Milford, CT)
1996-01-01
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.
Matrix with Prescribed Eigenvectors
ERIC Educational Resources Information Center
Ahmad, Faiz
2011-01-01
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…
Supersymmetric quantum matrix cosmology
NASA Astrophysics Data System (ADS)
López, J. L.; Obregón, O.
2015-12-01
We exhibit a relation between the SU(2) invariant matrix model arising from the quantization of the 11-dimensional supermembrane in the light cone gauge and supersymmetric quantum cosmology. We use a Dirac-like gamma matrix representation for the fermionic degrees of freedom and find explicit solutions to reduced lower dimensional SU(2) matrix models for the zero energy states. One of the solutions we encounter in the matrix model resembles exactly a wave function found independently in the context of SUSY quantum cosmology; this allows us to give these regularized models a physical meaning and shows a direct relation between the SU(2) matrix model and SUSY quantum cosmology.
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
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.
Fong, Jiunn N. C.; Yildiz, Fitnat H.
2015-01-01
Proteinaceous components of the biofilm matrix include secreted extracellular proteins, cell surface adhesins and protein subunits of cell appendages such as flagella and pili. Biofilm matrix proteins play diverse roles in biofilm formation and dissolution. They are involved in attaching cells to surfaces, stabilizing the biofilm matrix via interactions with exopolysaccharide and nucleic acid components, developing three-dimensional biofilm architectures, and dissolving biofilm matrix via enzymatic degradation of polysaccharides, proteins, and nucleic acids. In this chapter, we will review functions of matrix proteins in a selected set of microorganisms, studies of the matrix proteomes of Vibrio cholerae and Pseudomonas aeruginosa, and roles of outer membrane vesicles and of nucleoid-binding proteins in biofilm formation. PMID:26104709
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
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.
Matrix product operator representations
V. Murg; J. I. Cirac; B. Pirvu; F. Verstraete
2008-04-24
We show how to construct relevant families of matrix product operators in one and higher dimensions. Those form the building blocks for the numerical simulation methods based on matrix product states and projected entangled pair states. In particular, we construct translational invariant matrix product operators suitable for time evolution, and show how such descriptions are possible for Hamiltonians with long-range interactions. We illustrate how those tools can be exploited for constructing new algorithms for simulating quantum spin systems.
V. Rivasseau
2007-06-08
We extend the technique of constructive expansions to compute the connected functions of matrix models in a uniform way as the size of the matrix increases. This provides the main missing ingredient for a non-perturbative construction of the $\\phi^{\\star 4}_4$ field theory on the Moyal four dimensional space.
Fast methods for resumming matrix polynomials and Chebyshev matrix polynomials
Baer, Roi
expansions can be preferable when the matrix is sparse and these fast resummation algorithms are employed. Ó. Then sparse matrix multiplication methods can be used to evaluate the products entering the matrix polynomialFast methods for resumming matrix polynomials and Chebyshev matrix polynomials WanZhen Liang a,b,1
U.S. Geological Survey
2006-01-01
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
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).
Markowski, Adam S; Mannan, M Sam
2008-11-15
A risk matrix is a mechanism to characterize and rank process risks that are typically identified through one or more multifunctional reviews (e.g., process hazard analysis, audits, or incident investigation). This paper describes a procedure for developing a fuzzy risk matrix that may be used for emerging fuzzy logic applications in different safety analyses (e.g., LOPA). The fuzzification of frequency and severity of the consequences of the incident scenario are described which are basic inputs for fuzzy risk matrix. Subsequently using different design of risk matrix, fuzzy rules are established enabling the development of fuzzy risk matrices. Three types of fuzzy risk matrix have been developed (low-cost, standard, and high-cost), and using a distillation column case study, the effect of the design on final defuzzified risk index is demonstrated. PMID:18440700
Grassmann Matrix Quantum Mechanics
Anninos, Dionysios; Monten, Ruben
2015-01-01
We explore quantum mechanical theories whose fundamental degrees of freedom are rectangular matrices with Grassmann valued matrix elements. We study particular models where the low energy sector can be described in terms of a bosonic Hermitian matrix quantum mechanics. We describe the classical curved phase space that emerges in the low energy sector. The phase space lives on a compact Kahler manifold parameterized by a complex matrix, of the type discovered some time ago by Berezin. The emergence of a semiclassical bosonic matrix quantum mechanics at low energies requires that the original Grassmann matrices be in the long rectangular limit. We discuss possible holographic interpretations of such matrix models which, by construction, are endowed with a finite dimensional Hilbert space.
Grassmann Matrix Quantum Mechanics
Dionysios Anninos; Frederik Denef; Ruben Monten
2015-12-11
We explore quantum mechanical theories whose fundamental degrees of freedom are rectangular matrices with Grassmann valued matrix elements. We study particular models where the low energy sector can be described in terms of a bosonic Hermitian matrix quantum mechanics. We describe the classical curved phase space that emerges in the low energy sector. The phase space lives on a compact Kahler manifold parameterized by a complex matrix, of the type discovered some time ago by Berezin. The emergence of a semiclassical bosonic matrix quantum mechanics at low energies requires that the original Grassmann matrices be in the long rectangular limit. We discuss possible holographic interpretations of such matrix models which, by construction, are endowed with a finite dimensional Hilbert space.
A. Morozov
2012-04-18
Partition functions of eigenvalue matrix models possess a number of very different descriptions: as matrix integrals, as solutions to linear and non-linear equations, as tau-functions of integrable hierarchies and as special-geometry prepotentials, as result of the action of W-operators and of various recursions on elementary input data, as gluing of certain elementary building blocks. All this explains the central role of such matrix models in modern mathematical physics: they provide the basic "special functions" to express the answers and relations between them, and they serve as a dream model of what one should try to achieve in any other field.
Martens, Jon S. (Sunnyvale, CA); Hietala, Vincent M. (Placitas, NM); Plut, Thomas A. (Albuquerque, NM)
1995-01-01
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, J.S.; Hietala, V.M.; Plut, T.A.
1995-01-03
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.
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.
NASA Astrophysics Data System (ADS)
Köhler, Wolfgang
2011-06-01
A new classical theory of gravitation within the framework of general relativity is presented. It is based on a matrix formulation of four-dimensional Riemann-spaces and uses no artificial fields or adjustable parameters. The geometrical stress-energy tensor is derived from a matrix-trace Lagrangian, which is not equivalent to the curvature scalar R. To enable a direct comparison with the Einstein-theory a tetrad formalism is utilized, which shows similarities to teleparallel gravitation theories, but uses complex tetrads. Matrix theory might solve a 27-year-old, fundamental problem of those theories (Sect. 4.1). For the standard test cases (PPN scheme, Schwarz schild-solution) no differences to the Einstein-theory are found. However, the matrix theory exhibits novel, interesting vacuum solutions.
Tendon functional extracellular matrix.
Screen, Hazel R C; Berk, David E; Kadler, Karl E; Ramirez, Francesco; Young, Marian F
2015-06-01
This article is one of a series, summarizing views expressed at the Orthopaedic Research Society New Frontiers in Tendon Research Conference. This particular article reviews the three workshops held under the "Functional Extracellular Matrix" stream. The workshops focused on the roles of the tendon extracellular matrix, such as performing the mechanical functions of tendon, creating the local cell environment, and providing cellular cues. Tendon is a complex network of matrix and cells, and its biological functions are influenced by widely varying extrinsic and intrinsic factors such as age, nutrition, exercise levels, and biomechanics. Consequently, tendon adapts dynamically during development, aging, and injury. The workshop discussions identified research directions associated with understanding cell-matrix interactions to be of prime importance for developing novel strategies to target tendon healing or repair. PMID:25640030
Learning with matrix factorizations
Srebro, Nathan, 1974-
2004-01-01
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, ...
Wolfgang Koehler
2011-03-23
A new classical theory of gravitation within the framework of general relativity is presented. It is based on a matrix formulation of four-dimensional Riemann-spaces and uses no artificial fields or adjustable parameters. The geometrical stress-energy tensor is derived from a matrix-trace Lagrangian, which is not equivalent to the curvature scalar R. To enable a direct comparison with the Einstein-theory a tetrad formalism is utilized, which shows similarities to teleparallel gravitation theories, but uses complex tetrads. Matrix theory might solve a 27-year-old, fundamental problem of those theories (sec. 4.1). For the standard test cases (PPN scheme, Schwarzschild-solution) no differences to the Einstein-theory are found. However, the matrix theory exhibits novel, interesting vacuum solutions.
Nan, Feng, S.M. Massachusetts Institute of Technology
2009-01-01
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 ...
NASA Astrophysics Data System (ADS)
Tenreiro Machado, J. A.
2015-08-01
This paper addresses the matrix representation of dynamical systems in the perspective of fractional calculus. Fractional elements and fractional systems are interpreted under the light of the classical Cole-Cole, Davidson-Cole, and Havriliak-Negami heuristic models. Numerical simulations for an electrical circuit enlighten the results for matrix based models and high fractional orders. The conclusions clarify the distinction between fractional elements and fractional systems.
Characterisation of matrix entropies
Frank Hansen; Zhihua Zhang
2015-03-16
The notion of matrix entropy was introduced by Tropp and Chen with the aim of measuring the fluctuations of random matrices. It is a certain entropy functional constructed from a representing function with prescribed properties, and Tropp and Chen gave some examples. We give several abstract characterisations of matrix entropies together with a sufficient condition in terms of the second derivative of their representing function.
Optical coherency matrix tomography
NASA Astrophysics Data System (ADS)
Kagalwala, Kumel H.; Kondakci, H. Esat; Abouraddy, Ayman F.; Saleh, Bahaa E. A.
2015-10-01
The coherence of an optical beam having multiple degrees of freedom (DoFs) is described by a coherency matrix G spanning these DoFs. This optical coherency matrix has not been measured in its entirety to date—even in the simplest case of two binary DoFs where G is a 4?×?4 matrix. We establish a methodical yet versatile approach—optical coherency matrix tomography—for reconstructing G that exploits the analogy between this problem in classical optics and that of tomographically reconstructing the density matrix associated with multipartite quantum states in quantum information science. Here G is reconstructed from a minimal set of linearly independent measurements, each a cascade of projective measurements for each DoF. We report the first experimental measurements of the 4?×?4 coherency matrix G associated with an electromagnetic beam in which polarization and a spatial DoF are relevant, ranging from the traditional two-point Young’s double slit to spatial parity and orbital angular momentum modes.
Optical coherency matrix tomography
Kagalwala, Kumel H.; Kondakci, H. Esat; Abouraddy, Ayman F.; Saleh, Bahaa E. A.
2015-01-01
The coherence of an optical beam having multiple degrees of freedom (DoFs) is described by a coherency matrix G spanning these DoFs. This optical coherency matrix has not been measured in its entirety to date—even in the simplest case of two binary DoFs where G is a 4?×?4 matrix. We establish a methodical yet versatile approach—optical coherency matrix tomography—for reconstructing G that exploits the analogy between this problem in classical optics and that of tomographically reconstructing the density matrix associated with multipartite quantum states in quantum information science. Here G is reconstructed from a minimal set of linearly independent measurements, each a cascade of projective measurements for each DoF. We report the first experimental measurements of the 4?×?4 coherency matrix G associated with an electromagnetic beam in which polarization and a spatial DoF are relevant, ranging from the traditional two-point Young’s double slit to spatial parity and orbital angular momentum modes. PMID:26478452
Koo, H.; Falsetta, M.L.; Klein, M.I.
2013-01-01
Many infectious diseases in humans are caused or exacerbated by biofilms. Dental caries is a prime example of a biofilm-dependent disease, resulting from interactions of microorganisms, host factors, and diet (sugars), which modulate the dynamic formation of biofilms on tooth surfaces. All biofilms have a microbial-derived extracellular matrix as an essential constituent. The exopolysaccharides formed through interactions between sucrose- (and starch-) and Streptococcus mutans-derived exoenzymes present in the pellicle and on microbial surfaces (including non-mutans) provide binding sites for cariogenic and other organisms. The polymers formed in situ enmesh the microorganisms while forming a matrix facilitating the assembly of three-dimensional (3D) multicellular structures that encompass a series of microenvironments and are firmly attached to teeth. The metabolic activity of microbes embedded in this exopolysaccharide-rich and diffusion-limiting matrix leads to acidification of the milieu and, eventually, acid-dissolution of enamel. Here, we discuss recent advances concerning spatio-temporal development of the exopolysaccharide matrix and its essential role in the pathogenesis of dental caries. We focus on how the matrix serves as a 3D scaffold for biofilm assembly while creating spatial heterogeneities and low-pH microenvironments/niches. Further understanding on how the matrix modulates microbial activity and virulence expression could lead to new approaches to control cariogenic biofilms. PMID:24045647
BALANCED BILINEAR FORMS ON MATRIX AND MATRIX-LIKE COALGEBRAS
Beattie, Margaret
BALANCED BILINEAR FORMS ON MATRIX AND MATRIX-LIKE COALGEBRAS M. BEATTIE AND R. ROSE Abstract. In this short note, we determine all balanced bilinear forms for a matrix coalgebra and for one type of matrix-like coalgebra. 1. Introduction and preliminaries In this note we determine all balanced bilinear forms
Unit I-5 Matrix representations 1 Matrix representation
Birkett, Stephen
Unit I-5 Matrix representations 1 Unit I-5 Matrix representation of linear maps Unit I-5 Matrix in U Â· if v = a1v1 + ... + anvn then T(v) = a1T(v1) + ... + anT(vn) Unit I-5 Matrix representations 3 Example. Find the unique linear map T: R2 R2 so that T(1,2) = (2,3) and T(0,1) = (1,4). Unit I-5 Matrix
NASA Astrophysics Data System (ADS)
Deo, N.
2002-05-01
This paper discusses random matrix models that exhibit the unusual phenomena of having multiple solutions at the same point in phase space. These matrix models have gaps in their spectrum or density of eigenvalues. The free energy and certain correlation functions of these models show differences for the different solutions. This study presents evidence for the presence of multiple solutions both analytically and numerically. As an example this paper discusses the double-well matrix model with potential V(M)=-(?/2)M2+(g/4)M4, where M is a random N×N matrix (the M4 matrix model) as well as the Gaussian Penner model with V(M)=(?/2)M2-t ln M. First this paper studies what these multiple solutions are in the large N limit using the recurrence coefficient of the orthogonal polynomials. Second it discusses these solutions at the nonperturbative level to bring out some differences between the multiple solutions. Also presented are the two-point density-density correlation functions, which further characterize these models in a different universality class. A motivation for this work is that variants of these models have been conjectured to be models of certain structural glasses in the high temperature phase.
Matrixed business support comparison study.
Parsons, Josh D.
2004-11-01
The Matrixed Business Support Comparison Study reviewed the current matrixed Chief Financial Officer (CFO) division staff models at Sandia National Laboratories. There were two primary drivers of this analysis: (1) the increasing number of financial staff matrixed to mission customers and (2) the desire to further understand the matrix process and the opportunities and challenges it creates.
Nonnegative matrix factorization with -divergence
Cichocki, Andrzej
Nonnegative matrix factorization with -divergence Andrzej Cichocki a , Hyekyoung Lee b , Yong of Science and Technology San 31 Hyoja-dong, Nam-gu, Pohang 790-784, Korea Abstract Nonnegative matrix reduction, the goal of which is to decompose nonnegative data matrix X into a product of basis matrix
Pan, Feng; Kasiviswanathan, Shiva
2010-01-01
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.
J. Bedford; C. Papageorgakis; D. Rodriguez-Gomez; J. Ward
2007-02-20
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.
Wieczorek, Michael E.; LaMotte, Andrew E.
2010-01-01
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).
NASA Astrophysics Data System (ADS)
Elliott, John
2012-09-01
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.
Aleks Kleyn
2010-01-27
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.
Structured Multi-Matrix Variate, Matrix Polynomial Equations: Solution Techniques
Garimella Rama Murthy
2012-07-21
In this research paper, structured bi-matrix variate, matrix quadratic equations are considered. Some lemmas related to determining the eigenvalues of unknown matrices are proved. Also, a method of determining the diagonalizabe unknown matrices is provided. The results are generalized to multi-matrix variate, matrix polynomial equations. Briefly generalization to tensor variate polynomial equations is discussed. It is hoped that the results lead to important contributions in "non-commutative algebra".
Criteria for matrix selection in continuous fiber aluminum matrix composites
McCullough, C.; Galuska, P.; Pittman, S.R.
1996-10-01
Traditionally Continuous Fiber Aluminum Matrix Composites have been fabricated using high strength fibers and high strength matrices, often commercial alloys, with the goal of producing high strength composites. However the specific role of the choice of matrix alloy on composite properties has not been well established. One way to control composite tensile strength is to use coatings to introduce a low strength interface between fiber and matrix which tends to reduce the importance of the matrix selection, but unfortunately renders the transverse strength unacceptably low. Thus using a system with strong bonding between fiber and matrix is desirable, such as an alumina fiber/aluminum alloy matrix system. In this case the transverse strength is a strong function of the matrix strength. However, the longitudinal strength then depends largely on the characteristics of the matrix. The important role of the matrix is discussed using examples of alumina fibers in various aluminum alloy matrices. The key attributes are matrix constituent phases, alloy chemistry, alloy reactivity with the fiber, and matrix strength. From the understanding developed in these systems a set of design rules may be established for selecting an optimum matrix.
MATRIX MULTIPLY SCALAR FORMULATION
Browne, James C.
MATRIX MULTIPLY ALGORITHMS SCALAR FORMULATION a(i, j) = b(i, k) * c(k, j) , i = 1 Â Â Â n j = 1 AND j i k cobegin i : cobegin j : cobegin k : temp (i, j, k) := b(i, k) * c(k, j) x c(k, j) enddo a(i, j) := temp(i, j) coend coend i k j AND j k i cobegin i : cobegin j :
R. Dijkgraaf; E. Verlinde; H. Verlinde
1997-03-13
Via compactification on a circle, the matrix model of M-theory proposed by Banks et al 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 appearance of D-particle and D-membrane states.
MOP /Matrix Operation Programs system/
NASA Technical Reports Server (NTRS)
Muller, P. M.
1968-01-01
MOP /Matrix Operation Programs/ system consists of a set of FORTRAN 4 subroutines which are related through a small common allocation. The system accomplishes all matrix algebra operations plus related input-output and housekeeping details.
Hypercube matrix computation task
NASA Technical Reports Server (NTRS)
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
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).
Tabular Equation of State for Gold
NASA Astrophysics Data System (ADS)
Boettger, Jonathan; Honnell, Kevin; Peterson, Jeffrey; Greeff, Carl; Crockett, Scott
2011-06-01
A new, SESAME-type equation of state (EOS) is described for gold, suitable for use in hydrodynamic calculations. The EOS is tabulated on a rectangular temperature-and-density grid, spanning densities from 0 - 29 g/cc, temperatures from 0 - 85,000 K, and extending up to pressures of 1000 GPa. It is constructed using the standard decomposition of the pressure into a static-lattice cold curve, a thermal nuclear contribution, and a thermal electronic contribution. The cold curve is derived from a combination of empirical data and density functional theory, the thermal nuclear contribution from the Johnson model, and the thermal electronic contribution using Thomas-Fermi-Dirac theory. Pressures, internal energies, and Helmholtz free energies are tabulated as functions of temperature and density. Predictions for the room-temperature isotherm, principal Hugoniot, thermal expansion, heat capacity, and vapor pressure are compared with experimental data and with the EOS currently available in the SESAME library (SESAME 2700).
A Tabular Approach to Titration Calculations
ERIC Educational Resources Information Center
Lim, Kieran F.
2012-01-01
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…
Tabular equation of state for gold
NASA Astrophysics Data System (ADS)
Boettger, Jonathan; Honnell, Kevin G.; Peterson, Jeffrey H.; Greeff, Carl; Crockett, Scott
2012-03-01
A new, SESAME-type equation of state (EOS) , suitable for use in hydrodynamic calculations, is described for gold. Pressures, internal energies, and Helmholtz free energies are tabulated on a rectangular temperature-and-density grid, spanning densities from 0 - 36 g/cc, temperatures from 0 - 800 eV, and extending up to pressures of 800 GPa. The EOS is constructed using the standard decomposition of the pressure into a static-lattice cold curve, a thermal nuclear contribution, and a thermal electronic contribution. The cold curve is derived from existing diamond-anvil-cell measurements, the thermal nuclear contribution from the Johnson model, and the thermal electronic contribution using Thomas-Fermi-Dirac theory. Predictions of the new EOS (SESAME 2705) for the cold curve, roomtemperature isotherm, principal Hugoniot, thermal expansion, heat capacity, melt line, and vapor pressure compare favorably with experimental data and are superior to the EOS currently available in the SESAME library (SESAME 2700).
NASA Astrophysics Data System (ADS)
Miljutina, Maria A.; Miljutin, Dmitry M.
2015-01-01
The species-rich genus of marine free-living nematodes, Paracanthonchus Mikoletzky 1924 (Nematoda: Cyatholaimidae), is revised. The genus numbers 72 valid species; twenty are indicated as species inquirenda because of poor descriptions and/or doubtful placement in the genus. Species of the genus were described from all oceans and latitudes. Of valid species, 64 ones (90%) were described from the tidal or upper subtidal zones, four species were recorded from the medium or lower shelf, and three species are abyssal. Thirty one species (43%) are known from Europe and the Northern Africa; 19 and 9 ones were described from South and North America (respectively); 8 ones were recorded from Asia; and 6 ones from the Australian region. The type species, Paracanthonchus caecus Mikoletzky 1924 has been recorded by a number of authors from various oceans around the World, yet many of these specimens have only roughly resembled the type description. Evidently, this species represents a complex of closely related species. Possibly, the same situation is in some other Paracanthonchus species, the repeated findings of which have no strong resemblance to type specimens. A tabular key to species is provided. A new abyssal species Paracanthonchus mamubiae from the Zenkevich Rise (North-Western Pacific, off North Japan, 5350 m depth) is described. The new species is characterized by: the tail, which is long with a thin, cylindrical terminal section; the absence of lateral differentiation of the cuticle; the presence of two groups of lateral pores (level of posterior part of pharynx and in cloacal region); one large dorsal tooth and two pairs of small subventral teeth combined with pharyngostomal cuticular ridges forming two denticles which may appear as a third pair of subventral teeth; 3-5 indistinct tubular preanal supplements; and a massive, proximally paired gubernaculum possessing broad flattened plates on each distal end. Each flattened gubernacular plate bears numerous (50-60) small cusps and one large process.
On the Matrix Exponential Function
ERIC Educational Resources Information Center
Hou, Shui-Hung; Hou, Edwin; Pang, Wan-Kai
2006-01-01
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.
Matrix polynomials and structured linearizations.
Bigelow, Stephen
Matrix polynomials and structured linearizations. Advisor: Maria Isabel Bueno Cachadina Let P() = Akk + Ak-1k-1 + · · · + A0 (1) be a matrix polynomial of degree k 2, where the coefficients Ai are n × n matrices with entries in a field F. A matrix pencil L() = L1 - L0, with L1, L0 Mkn
The cellulose resource matrix.
Keijsers, Edwin R P; Y?lmaz, Gülden; van Dam, Jan E G
2013-03-01
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
Optical shutter switching matrix
NASA Astrophysics Data System (ADS)
Grove, Charles H.
1990-03-01
A switching matrix enables switching of optical signals from any of a plurality of optical input paths to selected optical output paths, without requiring physical reconnecting of the inputs or outputs. Plural broadband optical waveguides are defined preferably in otherwise non-transmissive quartz crystalline wafers, to provide relatively high signal isolation. The wafers are fused to electronic shutter windows situated in an array and discretely operable under processor x-y address control. Optical signals passed through actuated electronic shutter windows are summed in output wafers, having waveguide structure generally reverse to that of the input quartz wafers. Through selected segment actuation, optical signals from selected optical input paths may be transmitted or blocked at the electronically controlled shutter array, for being output on selected optical output paths. Alternatively, fiber optic bundles may replace input or output quartz wafers. The switching matrix is useful as a switching module which may be variously associated in series and/or parallel connections for obtaining a desired number of switching channels, and required levels of signal separation therewith. Input/output signal characteristics and parameters are maintained by power summation at the outputs with automatic gain control, regardless of the number of paths or the like selectively summed in a given output. Connectors may be used in conjunction with the optical input and output paths, whereby both electrical and optical signals may be switched. Various modules may include converters as built-in features, so as to meet particular applications.
The Matrix Exponential Gordon K. Smyth
Smyth, Gordon K.
The Matrix Exponential Gordon K. Smyth March 17, 1997 One of the most frequently occurring matrix functions is the matrix exponential, defined for a square matrix A by e At = 1 X j=0 (At) j j! : The matrix chain is in state j at time t, and A is the matrix of instantaneous transition rates. Another
Matrix Algebra September 1, 2015 1 / 4
Laison, Josh
Matrix Algebra September 1, 2015 1 / 4 #12;Matrix Algebra Four different ways of computing the matrix product AB: September 1, 2015 1 / 4 #12;Matrix Algebra Four different ways of computing the matrix row of A with the jth column of B. September 1, 2015 1 / 4 #12;Matrix Algebra Four different ways
Polynomial Supersymmetry for Matrix Hamiltonians
Andrey V. Sokolov
2013-07-16
We study intertwining relations for matrix one-dimensional, in general, non-Hermitian Hamiltonians by matrix differential operators of arbitrary order. It is established that for any matrix intertwining operator Q_N^- of minimal order N there is a matrix operator Q_{N'}^+ of different, in general, order N' that intertwines the same Hamiltonians as Q_N^- in the opposite direction and such that the products Q_{N'}^+Q_N^- and Q_N^-Q_{N'}^+ are identical polynomials of the corresponding Hamiltonians. The related polynomial algebra of supersymmetry is constructed. The problems of minimization and of reducibility of a matrix intertwining operator are considered and the criteria of minimizability and of reducibility are presented. It is shown that there are absolutely irreducible matrix intertwining operators, in contrast to the scalar case.
Hyaluronan: A Matrix Component
NASA Astrophysics Data System (ADS)
Rügheimer, Louise
2008-09-01
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.
NASA Astrophysics Data System (ADS)
Craps, Ben; Sethi, Savdeep; Verlinde, Erik
2005-10-01
The light-like linear dilaton background represents a particularly simple time-dependent 1/2 BPS solution of critical type-IIA superstring theory in ten dimensions. Its lift to M-theory, as well as its Einstein frame metric, are singular in the sense that the geometry is geodesically incomplete and the Riemann tensor diverges along a light-like subspace of codimension one. We study this background as a model for a big bang type singularity in string theory/M-theory. We construct the dual Matrix theory description in terms of a (1+1)-d supersymmetric Yang-Mills theory on a time-dependent world-sheet given by the Milne orbifold of (1+1)-d Minkowski space. Our model provides a framework in which the physics of the singularity appears to be under control.
Hastings, Matthew B
2009-01-01
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.
Mixed Mode Matrix Multiplication
Meng-Shiou Wu; Srinivas Aluru; Ricky A. Kendall
2004-09-30
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.
ERIC Educational Resources Information Center
Jairam, Dharmananda; Kiewra, Kenneth A.; Kauffman, Douglas F.; Zhao, Ruomeng
2012-01-01
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…
Synthetic Division and Matrix Factorization
ERIC Educational Resources Information Center
Barabe, Samuel; Dubeau, Franc
2007-01-01
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.
Layered metal matrix composites
Lu, L.; Li, G.; Lai, M.O.
1996-10-01
Metal matrix composite (MMC) with composition of Al-4.5 wt.%Cu reinforced by 10wt.%TiB{sub 2} or 15wt.%SiC particulate has been successfully fabricated using powder metallurgy technique. Disk, compression and beam specimens were prepared with (a) layered structure containing ductile Al-4.5wt.%Cu with brittle Al-4.5wt.%Cu/TiB{sub 2} or Al-4.5wt.%Cu/SiC layers, and (b) homogeneous constituent with composition of Al-4.5wt.%Cu/10wt.%TiB{sub 2}. The specimens for the fracture toughness measurement were built through three ductile-brittle-ductile alternating layers. For the beam specimens, the layers were built through brittle-ductile-brittle sequence. The brittle layer consisted of Al-4.5%Cu with fixed amount of reinforcement. Fracture toughness testing revealed an increase for layered composites although the total amount of the reinforcement was the same for all disk specimens. The increase in fracture toughness is due to the existence of ductile layers which manifests a strong influence on delaying the occurrence of fracture. It acts as a barrier to resist the propagation of crack and hence increases the fracture toughness of the layered MMC specimens. Delamination in the beam specimens was observed to be due to shear stresses. Fracture surfaces of both disk, compress and beam specimens were characterized using the SEM.
Hybridized polymer matrix composites
NASA Technical Reports Server (NTRS)
House, E. E.; Hoggatt, J. T.; Symonds, W. A.
1980-01-01
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.
Hypercube matrix computation task
NASA Technical Reports Server (NTRS)
Calalo, R.; Imbriale, W.; Liewer, P.; Lyons, J.; Manshadi, F.; Patterson, J.
1987-01-01
The Hypercube Matrix Computation (Year 1986-1987) task investigated the applicability of a parallel computing architecture to the solution of large scale electromagnetic scattering problems. Two existing electromagnetic scattering codes were selected for conversion to the Mark III Hypercube concurrent computing environment. They were selected so that the underlying numerical algorithms utilized would be different thereby providing a more thorough evaluation of the appropriateness of the parallel environment for these types of problems. The first code was a frequency domain method of moments solution, NEC-2, developed at Lawrence Livermore National Laboratory. The second code was a time domain finite difference solution of Maxwell's equations to solve for the scattered fields. Once the codes were implemented on the hypercube and verified to obtain correct solutions by comparing the results with those from sequential runs, several measures were used to evaluate the performance of the two codes. First, a comparison was provided of the problem size possible on the hypercube with 128 megabytes of memory for a 32-node configuration with that available in a typical sequential user environment of 4 to 8 megabytes. Then, the performance of the codes was anlyzed for the computational speedup attained by the parallel architecture.
Calkins, Noel C. (Los Alamos, NM)
1991-01-01
An armor system which utilizes glass. A plurality of constraint cells are mounted on a surface of a substrate, which is metal armor plate or a similar tough material, such that the cells almost completely cover the surface of the substrate. Each constraint cell has a projectile-receiving wall parallel to the substrate surface and has sides which are perpendicular to and surround the perimeter of the receiving wall. The cells are mounted such that, in one embodiment, the substrate surface serves as a sixth side or closure for each cell. Each cell has inside of it a plate, termed the front plate, which is parallel to and in contact with substantially all of the inside surface of the receiving wall. The balance of each cell is completely filled with a projectile-abrading material consisting of glass and a ceramic material and, in certain embodiments, a polymeric material. The glass may be in monolithic form or particles of ceramic may be dispersed in a glass matrix. The ceramic material may be in monolithic form or may be in the form of particles dispersed in glass or dispersed in said polymer.
Matrix Model Approach to Cosmology
Chaney, A; Stern, A
2015-01-01
We perform a systematic search for rotationally invariant cosmological solutions to matrix models, or more specifically the bosonic sector of Lorentzian IKKT-type matrix models, in dimensions $d$ less than ten, specifically $d=3$ and $d=5$. After taking a continuum (or commutative) limit they yield $d-1$ dimensional space-time surfaces, with an attached Poisson structure, which can be associated with closed, open or static cosmologies. For $d=3$, we obtain recursion relations from which it is possible to generate rotationally invariant matrix solutions which yield open universes in the continuum limit. Specific examples of matrix solutions have also been found which are associated with closed and static two-dimensional space-times in the continuum limit. The solutions provide for a matrix resolution of cosmological singularities. The commutative limit reveals other desirable features, such as a solution describing a smooth transition from an initial inflation to a noninflationary era. Many of the $d=3$ soluti...
Matrix Representation of Special Relativity
Wolfgang Koehler
2007-03-08
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.
L20: Sparse Matrix Algorithms, SIMD review!
Hall, Mary W.
11/20/12 1 L20: Sparse Matrix Algorithms, SIMD review! November 15, 2012! Administrative Â·CUDA The code in sparse_matvec.c is a sequential version of a sparse matrix-vector multiply. The matrix: Sparse input matrices which were generated from the MatrixMarket (see http://math.nist.gov/Matrix
RANK-SPARSITY INCOHERENCE FOR MATRIX DECOMPOSITION
Qiu, Robert Caiming
sparse matrix to an unknown low-rank matrix. Our goal is to decompose the given matrix into its sparse-rank components given no prior knowledge about the sparsity pattern of the sparse matrix, or the rank of the low interpretations depending on the application. In a statistical model selection setting, the sparse matrix can
Robust Matrix Decomposition with Sparse Corruptions
de Sa, Virginia
1 Robust Matrix Decomposition with Sparse Corruptions Daniel Hsu, Sham M. Kakade, and Tong Zhang Abstract--Suppose a given observation matrix can be decomposed as the sum of a low-rank matrix and a sparse of a sparse matrix XS and a low-rank matrix XL. For instance, in the application to PCA, XL represents
The Matrix Exponential Gordon K. Smyth
Smyth, Gordon K.
The Matrix Exponential Gordon K. Smyth Department of Mathematics University of Queensland 17 March 1997 One of the most frequently occurring matrix functions is the matrix exponential, defined for a square matrix A by eAt = j=0 (At)j j! . The matrix exponential arises from the differential equation x
PARALLEL MATRIX MULTIPLICATION: A SYSTEMATIC JOURNEY
Batory, Don
PARALLEL MATRIX MULTIPLICATION: A SYSTEMATIC JOURNEY MARTIN D. SCHATZ, ROBERT A. VAN DE GEIJN- trix matrix multiplication algorithms. The journey starts with a description of how matrices implementation of matrix-vector multiplication and rank-1 update, continues on to reveal a fam- ily of matrix-matrix
MatrixDB, the extracellular matrix interaction Emilie Chautard1
Thierry-Mieg, Nicolas
polysaccharides that are organized in a tissue-specific manner. Major components of the extracel- lular matrix), and is a reservoir of bioactive fragments, called matricryptins, that are released upon limited proteolysis
String theory and matrix models
Yoneya, T
1996-01-01
It is generally accepted that the double-scaled 1D matrix model is equivalent to the c=1 string theory with tachyon condensation. There remain however puzzles that are to be clarified in order to utilize this connection for our quest towards possible non-perturbative formulation of string theory. We discuss some of the issues that are related to the space-time interpretation of matrix models, in particular, the questions of leg poles, causality, and black hole background. Finally, a speculation about a possible connection of a deformed matrix model with the idea of Dirichret brane is presented.
Canonical density matrix perturbation theory
Niklasson, Anders M N; Rubensson, Emanuel H; Rudberg, Elias
2015-01-01
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.
Genotype imputation via matrix completion
Chi, Eric C.; Zhou, Hua; Chen, Gary K.; Del Vecchyo, Diego Ortega; Lange, Kenneth
2013-01-01
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
High Temperature Polymer Matrix Composites
NASA Technical Reports Server (NTRS)
1985-01-01
These are the proceedings of the High Temperature Polymer Matrix Composites Conference held at the NASA Lewis Research Center on March 16 to 18, 1983. The purpose of the conference is to provide scientists and engineers working in the field of high temperature polymer matrix composites an opportunity to review, exchange, and assess the latest developments in this rapidly expanding area of materials technology. Technical papers are presented in the following areas: (1) matrix development; (2) adhesive development; (3) characterization; (4) environmental effects; and (5) applications.
Mechanotransduction and extracellular matrix homeostasis
Humphrey, Jay D.; Dufresne, Eric R.; Schwartz, Martin A.
2015-01-01
Preface Soft connective tissues at steady state are yet dynamic; resident cells continually read environmental cues and respond to promote homeostasis, including maintenance of the mechanical properties of the extracellular matrix that are fundamental to cellular and tissue health. The mechanosensing process involves assessment of the mechanics of the matrix by the cells through integrins and the actomyosin cytoskeleton, and is followed by a mechano-regulation process that includes the deposition, rearrangement, or removal of matrix to maintain overall form and function. Progress toward understanding the molecular, cellular, and tissue scale effects that promote mechanical homeostasis has helped identify key questions for future research. PMID:25355505
NASA Astrophysics Data System (ADS)
Oehlmann, Dietmar; Ohlmann, Odile M.; Danzebrink, Hans U.
2005-04-01
The research of Odile Meulien and Dietmar Ohlmann is about perceiving a multidimensional world. Not about the cyberspace created for new cinema creation, nor the reality which seems to be created by communication. It's the search for the reality we perceive, when the mind "touches" an object with its senses. In fact, it is a study of the surface of an object, which we can record in its visual appearing, its structure, shape and colors. When using photographic media, the tactile sense of the structure is missing, when using some other reproductive media; we experience somewhere a sensation of fault, something different. When using holography, we are able to record some three dimensional shape which has in fact a lot of parameter of a realistic copy. What is missing is the touch, the smell, the way we can go close and far, surround the object, relate the reflected light to its surrounding. The only interesting attribute of a hologram is for Dietmar Ohlmann its capacity to illustrate a continuum. He likes its changing diffractive character during daytime and surrounds lighting. For Odile Meulien the continuum of a hologram represents a new possible model for understanding wholeness in a social context. In fact, both are working on an educational process together, helping children and adults to find a new position of their own in harmony with living surrounding. Dietmar Ohlmann is working on his artistic side, while Odile Meulien works on educational programs experiencing the perspective of a curator and social analyst. New is the implication of using the latest of the techniques like the atomic force microscopy, which make possible to touch the holographic grating while the holographic image remains untouched. In other words it is the reverse of the usual approach of objects which at first we touch to investigate further. Their difference in experiencing and perceiving scientific and technical approach brings a lot of paradigm in their discussion. Together they will perform this exchange, as a matrix, understood as source, of new ideas.
Sparse and low-rank matrix decompositions
Chandrasekaran, Venkat
We consider the following fundamental problem: given a matrix that is the sum of an unknown sparse matrix and an unknown low-rank matrix, is it possible to exactly recover the two components? Such a capability enables a ...
Introduction Matrix multiplication based linear algebra
Pernet, Clément
Introduction Matrix multiplication based linear algebra Computing the characteristic polynomial Conclusion and perspectives Matrix Multiplication Based Computations of the Characteristic Polynomial Clément Meeting ORCCA-SCG, February 9, 2007 Clément Pernet Matrix multiplication based Characteristic Polynomial
Lecture 12: Chain Matrix Multiplication CLRS Section 15.2
Wu, Dekai
Lecture 12: Chain Matrix Multiplication CLRS Section 15.2 Outline of this Lecture Recalling matrix multiplication. The chain matrix multiplication problem. A dynamic programming algorithm for chain ma- trix multiplication. 1 #12;Recalling Matrix Multiplication Matrix: An ¡ ¢ matrix
Lung Multiple Primary Rules Matrix
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.
Stochastic determination of matrix determinants
Dorn, Sebastian
2015-01-01
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...
Performance Appraisal for Matrix Management.
ERIC Educational Resources Information Center
Edwards, M. R.; Sproull, J. Ruth
1985-01-01
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)
Stochastic determination of matrix determinants.
Dorn, Sebastian; Ensslin, Torsten A
2015-07-01
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. While 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, there is no stochastic estimate for its determinant. We introduce a probing method for the logarithm of a determinant of a linear operator. Our 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 Bayesian inference, in particular evidence calculations, model comparison, and posterior determination. PMID:26274302
Simplicial matrix-tree theorems
Duval, Art M.; Klivans, Caroline J.; Martin, Jeremy L.
2009-01-01
We generalize the definition and enumeration of spanning trees from the setting of graphs to that of arbitrary-dimensional simplicial complexes ?, extending an idea due to G. Kalai. We prove a simplicial version of the Matrix-Tree Theorem...
Stochastic determination of matrix determinants
NASA Astrophysics Data System (ADS)
Dorn, Sebastian; Enßlin, Torsten A.
2015-07-01
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. While 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, there is no stochastic estimate for its determinant. We introduce a probing method for the logarithm of a determinant of a linear operator. Our 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 Bayesian inference, in particular evidence calculations, model comparison, and posterior determination.
P. Descouvemont; D. Baye
2010-01-05
The different facets of the $R$-matrix method are presented pedagogically in a general framework. Two variants have been developed over the years: $(i)$ The "calculable" $R$-matrix method is a calculational tool to derive scattering properties from the Schr\\"odinger equation in a large variety of physical problems. It was developed rather independently in atomic and nuclear physics with too little mutual influence. $(ii)$ The "phenomenological" $R$-matrix method is a technique to parametrize various types of cross sections. It was mainly (or uniquely) used in nuclear physics. Both directions are explained by starting from the simple problem of scattering by a potential. They are illustrated by simple examples in nuclear and atomic physics. In addition to elastic scattering, the $R$-matrix formalism is applied to transfer and radiative-capture reactions. We also present more recent and more ambitious applications of the theory in nuclear physics.
Molybdenum disilicide alloy matrix composite
Petrovic, John J. (Los Alamos, NM); Honnell, Richard E. (Los Alamos, NM); Gibbs, W. Scott (Los Alamos, NM)
1991-01-01
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.
Molybdenum disilicide alloy matrix composite
Petrovic, John J. (Los Alamos, NM); Honnell, Richard E. (Los Alamos, NM); Gibbs, W. Scott (Los Alamos, NM)
1990-01-01
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.
Molybdenum disilicide alloy matrix composite
Petrovic, J.J.; Honnell, R.E.; Gibbs, W.S.
1991-12-03
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.
Minimal Realizations of Supersymmetry for Matrix Hamiltonians
Alexander A. Andrianov; Andrey V. Sokolov
2014-09-27
The notions of weak and strong minimizability of a matrix intertwining operator are introduced. Criterion of strong minimizability of a matrix intertwining operator is revealed. Criterion and sufficient condition of existence of a constant symmetry matrix for a matrix Hamiltonian are presented. A method of constructing of a matrix Hamiltonian with a given constant symmetry matrix in terms of a set of arbitrary scalar functions and eigen- and associated vectors of this matrix is offered. Examples of constructing of $2\\times2$ matrix Hamiltonians with given symmetry matrices for the cases of different structure of Jordan form of these matrices are elucidated.
Quark Mass Matrix with a Structure of a Rank One Matrix Plus a Unit Matrix
H. Fusaoka; Y. Koide
1995-01-14
A quark mass matrix model $M_q=M_e^{1/2} O_q M_e^{1/2} $ is proposed where $M_e^{1/2}={\\rm diag}(\\sqrt{m_e},\\sqrt{m_\\mu},\\sqrt{m_\\tau})$ and $O_q$ is a unit matrix plus a rank one matrix. Up- and down-quark mass matrices $M_u$ and $M_d$ are described in terms of charged lepton masses and additional three parameters (one in $M_u$ and two in $M_d$). The model can predict reasonable quark mass ratios (not only $m_u/m_c$, $m_c/m_t$, $m_d/m_s$ and $m_s/m_b$, but also $m_u/m_d$) and Kobayashi-Maskawa matrix elements.
Octonionic matrix representation and electromagnetism
NASA Astrophysics Data System (ADS)
Chanyal, B. C.
2014-12-01
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.
Propagation of Errors for Matrix Inversion
M. Lefebvre; R. K. Keeler; R. Sobie; J. White
1999-09-17
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.
Compiling Imperfectlynested Sparse Matrix Codes with Dependences
Stodghill, Paul
Compiling ImperfectlyÂnested Sparse Matrix Codes with Dependences Nawaaz Ahmed, Nikolay Mateev Abstract. We present compiler technology for generating sparse matrix code from (i) dense matrix code to compute with zeros. Figure 1 shows a sparse matrix and a number of commonly used compressed formats
Rank-Sparsity Incoherence for Matrix Decomposition
Chandrasekaran, Venkat
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 ...
Sparse and Low-Rank Matrix Decompositions
Heaton, Thomas H.
Sparse and Low-Rank Matrix Decompositions Venkat Chandrasekaran Sujay Sanghavi Pablo A. Parrilo 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 number of applications
Structured sparse methods for matrix factorization
Bach, Francis
Structured sparse methods for matrix factorization Francis Bach Willow project, INRIA - Ecole. Ponce, G. Sapiro #12;Structured sparse methods for matrix factorization Outline Â· Learning problems = T U V M Â· Sparse decomposition: U sparse U= VM T #12;Structured sparse matrix factorizations Â· Matrix
Matrix Analysis, CAAM 335, Spring 2012
Matrix Analysis, CAAM 335, Spring 2012 Steven J Cox #12;Preface Bellman has called matrix theory and scientists have found in matrix theory a language for repre- senting and analyzing multivariable systems. Our and the power of matrix theory in the analysis and synthesis of such systems. Beginning with modeling
Matrix formalism of synchrobetatron coupling
NASA Astrophysics Data System (ADS)
Huang, Xiaobiao
2007-01-01
In this paper we present a complete linear synchrobetatron coupling formalism by studying the transfer matrix which describes linear horizontal and longitudinal motions. With the technique established in the linear horizontal-vertical coupling study [D. Sagan and D. Rubin, Phys. Rev. ST Accel. Beams 2, 074001 (1999)PRABFM1098-440210.1103/PhysRevSTAB.2.074001], we found a transformation to block diagonalize the transfer matrix and decouple the betatron motion and the synchrotron motion. By separating the usual dispersion term from the horizontal coordinate first, we were able to obtain analytic expressions of the transformation under reasonable approximations. We also obtained the perturbations to the betatron tune and the Courant-Snyder functions. The closed-orbit changes due to finite energy gains at rf cavities and radiation energy losses were studied by the 5×5 extended transfer matrix with the fifth column describing kicks in the 4-dimension phase space.
Matrix Model Approach to Cosmology
A. Chaney; Lei Lu; A. Stern
2015-11-29
We perform a systematic search for rotationally invariant cosmological solutions to matrix models, or more specifically the bosonic sector of Lorentzian IKKT-type matrix models, in dimensions $d$ less than ten, specifically $d=3$ and $d=5$. After taking a continuum (or commutative) limit they yield $d-1$ dimensional space-time surfaces, with an attached Poisson structure, which can be associated with closed, open or static cosmologies. For $d=3$, we obtain recursion relations from which it is possible to generate rotationally invariant matrix solutions which yield open universes in the continuum limit. Specific examples of matrix solutions have also been found which are associated with closed and static two-dimensional space-times in the continuum limit. The solutions provide for a matrix resolution of cosmological singularities. The commutative limit reveals other desirable features, such as a solution describing a smooth transition from an initial inflation to a noninflationary era. Many of the $d=3$ solutions have analogues in higher dimensions. The case of $d=5$, in particular, has the potential for yielding realistic four-dimensional cosmologies in the continuum limit. We find four-dimensional de Sitter $dS^4$ or anti-de Sitter $AdS^4$ solutions when a totally antisymmetric term is included in the matrix action. A nontrivial Poisson structure is attached to these manifolds which represents the lowest order effect of noncommutativity. For the case of $AdS^4$, we find one particlular limit where the lowest order noncommutativity vanishes at the boundary, but not in the interior.
Functions Preserving Matrix Groups and Iterations for the Matrix Square Root
Higham, Nicholas J.
Functions Preserving Matrix Groups and Iterations for the Matrix Square Root Nicholas J. Higham, D ISSN 1749-9097 #12;FUNCTIONS PRESERVING MATRIX GROUPS AND ITERATIONS FOR THE MATRIX SQUARE ROOT NICHOLAS J. HIGHAM, D. STEVEN MACKEY, NILOUFER MACKEY, AND FRANCÂ¸OISE TISSEUR SIAM J. MATRIX ANAL. APPL. c
Leiserson, Charles E.
Parallel Sparse Matrix-Vector and Matrix-Transpose-Vector Multiplication Using Compressed Sparse to be computed efficiently in parallel, where A is an n Ã? n sparse matrix with nnz n nonzeros and x is a dense n Compressed sparse blocks, compressed sparse columns, com- pressed sparse rows, matrix transpose, matrix
The Matrix Unwinding Function, with an Application to Computing the Matrix Exponential
Higham, Nicholas J.
The Matrix Unwinding Function, with an Application to Computing the Matrix Exponential Mary. MATRIX ANAL. APPL. c 2014 Society for Industrial and Applied Mathematics Vol. 35, No. 1, pp. 88109 THE MATRIX UNWINDING FUNCTION, WITH AN APPLICATION TO COMPUTING THE MATRIX EXPONENTIAL MARY APRAHAMIAN
Integrability and generalized monodromy matrix
Lhallabi, T.; Moujib, A.
2007-09-15
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.
[Matrix Support: a bibliographical study].
Iglesias, Alexandra; Avellar, Luziane Zacché
2014-09-01
This article presents a bibliographical review of matrix support in mental health. A search was conducted in the Virtual Health Library and the LILACS, SciELO and Google Scholar databases using the key words: "matrix support in mental health." Fourteen articles were located with the desired characteristics, which indicates that only a restricted number of publications are in circulation. The articles were analyzed with respect to their structural and methodological aspects, which revealed the absolute predominance of the use of qualitative methods and health professionals as the target research population. The same articles were then analyzed for their theoretical discussions. Among other issues, the importance of matrix support to enhance the primary health care teams provided to people suffering from psychic distress is highlighted. However, there is still considerable confusion regarding the proposal of the matrix support and shared responsibilities between teams of reference and mental health professionals, which emphasizes the need for training of these professionals, as well as better coordination and organization of the mental health care network. PMID:25184584
Some considerations of matrix equations using the concept of reproductivity
Malesevic, Branko
2011-01-01
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.
Matrix metalloproteinases in fish biology and matrix turnover.
Pedersen, Mona E; Vuong, Tram T; Rønning, Sissel B; Kolset, Svein O
2015-01-01
Matrix metalloproteinases have important functions for tissue turnover in fish, with relevance both for the fish industry and molecular and cellular research on embryology, inflammation and tissue repair. These metalloproteinases have been studied in different fish types, subjected to both aquaculture and experimental conditions. This review highlights studies on these metalloproteinases in relation to both fish quality and health and further, the future importance of fish for basic research studies. PMID:25617492
q-Virasoro constraints in matrix models
Nedelin, Anton
2015-01-01
The Virasoro constraints play the important role in the study of matrix models and in understanding of the relation between matrix models and CFTs. Recently the localization calculations in supersymmetric gauge theories produced new families of matrix models and we have very limited knowledge about these matrix models. We concentrate on elliptic generalization of hermitian matrix model which corresponds to calculation of partition function on $S^3 \\times S^1$ for vector multiplet. We derive the $q$-Virasoro constraints for this matrix model. We also observe some interesting algebraic properties of the $q$-Virasoro algebra.
Reticker-Flynn, Nathan E.
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 ...
The Simplest Neutrino Mass Matrix
P. F. Harrison; W. G. Scott
2004-04-20
We motivate the simplest ansatz for the neutrino mass matrix consistent with the data from neutrino oscillation experiments, and admitting CP violation. It has only two free parameters: an arbitrary mass-scale and a small dimensionless ratio. This mass matrix exhibits two symmetries, Democracy and Mutativity, which respectively ensure trimaximal mixing of the |nu_2> mass eigenstate, and mixing parameter values |theta_{23}|=45 degrees and |delta|=90 degrees, consistent with bimaximal mixing of the |nu_3> mass eigenstate. A third constraint relates the smallness of |U_{e3}|^2 to that of the mass-squared difference ratio, Delta m^2_sol/Delta m^2_atm, yielding the prediction sin(theta_{13})=sqrt{2 Delta m^2_sol/3 Delta m^2_atm} ~ 0.13 +- 0.03.
Sapphire reinforced alumina matrix composites
NASA Technical Reports Server (NTRS)
Jaskowiak, Martha H.; Setlock, John A.
1994-01-01
Unidirectionally reinforced A1203 matrix composites have been fabricated by hot pressing. Approximately 30 volume % of either coated or uncoated sapphire fiber was used as reinforcement. Unstabilized ZrO2 was applied as the fiber coating. Composite mechanical behavior was analyzed both after fabrication and after additional heat treatment. The results of composite tensile tests were correlated with fiber-matrix interfacial shear strengths determined from fiber push-out tests. Substantially higher strength and greater fiber pull-out were observed for the coated fiber composites for all processing conditions studied. The coated fiber composites retained up to 95% and 87% of their as-fabricated strength when heat treated at 14000C for 8 or 24 hours, respectively. Electron microscopy analysis of the fracture surfaces revealed extensive fiber pull-out both before and after heat treatment.
Corrosion of Titanium Matrix Composites
Covino, B.S., Jr.; Alman, D.E.
2002-09-22
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.
Matrix metalloproteinases in cardiovascular disease
Liu, Peter; Sun, Mei; Sader, Sawsan
2006-01-01
Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes that are regulated by inflammatory signals to mediate changes in extracellular matrix. Members of the MMP family share sequence homology, act on interstitial protein substrates, acutely participate in inflammatory processes and chronically mediate tissue remodelling. MMPs are important in vascular remodelling, not only in the overall vasculature architecture but also, more importantly, in the advancing atherosclerotic plaque. MMP activation modifies the architecture of the plaque and may directly participate in the process of plaque rupture. MMPs also participate in cardiac remodelling following myocardial infarction and development of dilated cardiomyopathy. Soluble MMPs are now potential biomarkers in delineating cardiovascular risk for plaque rupture and coronary risk. They also constitute innovative direct or indirect targets to modify cardiovascular tissue remodelling in atherosclerosis and heart failure. PMID:16498509
Matrix models and graph colouring
NASA Astrophysics Data System (ADS)
Cicuta, Giovanni M.; Molinari, Luca; Montaldi, Emilio
1993-06-01
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.
Melanoma Multiple Primary Rules Matrix
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
Kidney Multiple Primary Rules Matrix
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
Colon Multiple Primary Rules Matrix
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
Chemical Additive Selection in Matrix Acidizing
Weidner, Jason 1981-
2011-05-09
Matrix Acidizing Basics: Carbonates ............................................. 3 Matrix Acidizing Basics: Sandstones ............................................. 6 II IRON-RELATED FORMATION DAMAGE, THE IMPORTANCE OF TUBING PICKLING... AND CONSIDERATIONS FOR HIGH TEMPERATURE WELLS .............................................................................. 11 The Importance of Tubing Pickling ............................................... 16 For Wells in High...
Experimental Space Weathering of Carbonaceous Chondrite Matrix
NASA Astrophysics Data System (ADS)
Keller, L. P.; Christoffersen, R.; Dukes, C. A.; Baragiola, R. A.; Rahman, Z.
2015-11-01
Helium ion irradiation of Murchison matrix resulted in amorphization of the matrix phyllosilicates, loss of OH, surface vesiculation, and a significant reduction of the Fe3+/Fe2+ ratio in fine-grained phyllosilicates.
Nuclear matrix elements for double beta decay
Vadim Rodin
2009-10-30
The present status of calculations of the nuclear matrix elements for neutrinoless double beta decay is reviewed. A proposal which allows in principle to measure the neutrinoless double beta decay Fermi matrix element is briefly described.
Random Matrix theory approach to Quantum mechanics
K. V. S. Shiv Chaitanya
2015-01-27
In this paper, we give random matrix theory approach to the quantum mechanics using the quantum Hamilton-Jacobi formalism. We show that the bound state problems in quantum mechanics are analogous to solving Gaussian unitary ensemble of random matrix theory. This study helps in identify the potential appear in the joint probability distribution function in the random matrix theory as a super potential. This approach allows to extend the random matrix theory to the newly discovered exceptional polynomials.
Teaching Tip: When a Matrix and Its Inverse Are Stochastic
ERIC Educational Resources Information Center
Ding, J.; Rhee, N. H.
2013-01-01
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.
Metal-matrix composites: Status and prospects
NASA Technical Reports Server (NTRS)
1974-01-01
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.
COMPUTATION OF MATRIX NORMS WITH APPLICATIONS
Nemirovski, Arkadi
COMPUTATION OF MATRIX NORMS WITH APPLICATIONS TO ROBUST OPTIMIZATION Research Thesis Submitted of the Technion is gratefully acknowledged. i #12;ii #12;Contents 1 Introduction 1 1.1 Matrix Norm problem: setting and motivation . . . . . . . . . . . . . . . . . . . 1 1.1.1 Matrix Norm problem
In vivo imaging of extracellular matrix
Cai, Long
stromal cell-matrix interactions for several days in live mice. We show that the matrix-modifying hormoneIn vivo imaging of extracellular matrix remodeling by tumor- associated fibroblasts Jean Y Perentes L Munn1, Rakesh K Jain1 & Yves Boucher1 Here we integrated multiphoton laser scanning microscopy
SPARSE MATRIX MULTIPLICATION ON AN ASSOCIATIVE PROCESSOR
Ginosar, Ran
SPARSE MATRIX MULTIPLICATION ON AN ASSOCIATIVE PROCESSOR L. Yavits, A. Morad, R. Ginosar Abstract--Sparse matrix multiplication is an important component of linear algebra computations. Implementing sparse of vector dot product does not depend on the vector size. Four sparse matrix multiplication algorithms
Rescheduling for Locality in Sparse Matrix Computations
Strout, Michelle Mills
Rescheduling for Locality in Sparse Matrix Computations Michelle Mills Strout, Larry Carter transformations can be used to im- prove data locality. However, sparse matrix computations have non-aÃ?ne loop is still in the cache upon reuse. This paper presents a technique for tiling sparse matrix computations
SPARSE MATRIX IMPLEMENTATION IN OCTAVE David Bateman
Adler, Andy
SPARSE MATRIX IMPLEMENTATION IN OCTAVE David Bateman , Andy Adler Centre de Recherche, Motorola extension of DIFFCrash uses octave's sparse matrix functions (and large computers with lots of memory of storing sparse matrix data. What all of the methods have in common is that they attempt to reduce
Fast sparse matrix multiplication Raphael Yuster
Yuster, Raphael
Fast sparse matrix multiplication Raphael Yuster Uri Zwick Abstract Let A and B two n Ã? n.38 ) algebraic operations. Obtaining a fast sparse matrix multiplication algorithm that beats the naive method are extremely sparse. The naive matrix multiplication algorithm, on the other hand, can be used to multiply two
SPARSITY: Optimization Framework for Sparse Matrix Kernels
Yelick, Katherine
SPARSITY: Optimization Framework for Sparse Matrix Kernels # EunÂJin School Computer Science California, Berkeley Abstract Sparse matrixÂvector multiplication important computational kernel performs build sparse matrix kerÂ nels tuned matrices machines. Sparsity combines traditional techniques
Symmetry in Matrix Models Pierre Flener
Walsh, Toby
-d 0/1 matrix representing which cards go into which racks [6]. By identifying the central roleSymmetry in Matrix Models Pierre Flener , Alan Frisch Â¡ , Brahim Hnich Â¢ , Zeynep Kiziltan, and configuration) can be modelled as constraint programs based on matrices of decision variables. In such matrix
Random Matrix Theory and its Innovative Applications
Edelman, Alan
Random Matrix Theory and its Innovative Applications Alan Edelman and Yuyang Wang Abstract Recently more and more disciplines of science and engineering have found Random Matrix Theory valuable. Some these applications and MATLAB experiments allowing a reader immediate access to the ideas. 1 Random Matrix Theory
Martin, Ralph R.
___________________________________________________________________________________________________ Estimating the Fundamental Matrix via Constrained Least-Squares: A Convex Approach Graziano Chesi, AndreaÐIn this paper, a new method for the estimation of the fundamental matrix from point correspondences is presented on the fundamental matrix. It is shown how this nonconvex optimization problem can be solved avoiding local minima
Matrix Analysis Unit code: MATH36001
Sidorov, Nikita
MATH36001 Matrix Analysis Unit code: MATH36001 Credit Rating: 10 Unit level: Level 3 Teaching). Familiarity with Matlab is helpful but not essential. Aims To introduce students to matrix analysis through decomposition, and matrix functions. This is archived information. Please visit http
Matrix Completion with Queries Natali Ruchansky
Crovella, Mark
Matrix Completion with Queries Natali Ruchansky Boston University natalir@cs.bu.edu Mark Crovella applications, e.g., recommender systems and traffic monitoring, the data comes in the form of a matrix that is only partially observed and low rank. A fundamental data- analysis task for these datasets is matrix
Matrix Operations Recall that an matrix A is a rectangular array of scalars arranged in rows and
Lee, Carl
Matrix Operations Recall that an matrix A is a rectangular array of scalars arranged in rows and columns: We will also denote the matrix A by . In the case we call a square matrix. If all the entries of the matrix A are zero, we call A the zero matrix and denote it by . The term matrix was first used in 1850
Accelerating Sparse Matrix-Matrix Multiplication with 3D-Stacked Logic-in-Memory Hardware
Franchetti, Franz
Accelerating Sparse Matrix-Matrix Multiplication with 3D-Stacked Logic-in-Memory Hardware Qiuling of sparse matrix data that is held in a 3D DRAM system. We build a customized content addressable memory accelerator layers that are stacked in between DRAM dies for the efficient sparse matrix operations. Through
The effect of the matrix on film properties in matrix-assisted pulsed laser evaporation
Vertes, Akos
The effect of the matrix on film properties in matrix-assisted pulsed laser evaporation D. M. Bubba amu have been deposited by matrix-assisted pulsed laser evaporation MAPLE . The deposition was carried as a matrix. Time-of-flight analysis was performed using a quadrupole mass spectrometer to monitor evaporation
Brain Extracellular Matrix in Neurodegeneration
Bonneh-Barkay, Dafna; Wiley, Clayton A.
2009-01-01
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
Bohn, Mark S. (Golden, CO); Anselmo, Mark (Arvada, CO)
2001-01-01
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.
Characterization of Metal Matrix Composites
NASA Technical Reports Server (NTRS)
Daniel, I. M.; Chun, H. J.; Karalekas, D.
1994-01-01
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.
Automatic Generation of Partitioned Matrix Expressions for Matrix Operations
NASA Astrophysics Data System (ADS)
Fabregat-Traver, Diego; Bientinesi, Paolo
2010-09-01
We target the automatic generation of formally correct algorithms and routines for linear algebra operations. Given the broad variety of architectures and configurations with which scientists deal, there does not exist one algorithmic variant that is suitable for all scenarios. Therefore, we aim to generate a family of algorithmic variants to attain high-performance for a broad set of scenarios. One of the authors has previously demonstrated that automatic derivation of a family of algorithms is possible when the Partitioned Matrix Expression (PME) of the target operation is available. The PME is a recursive definition that states the relations between submatrices in the input and the output operands. In this paper we describe all the steps involved in the automatic derivation of PMEs, thus making progress towards a fully automated system.
Possibilities for a density matrix theory
NASA Astrophysics Data System (ADS)
Nooijen, Marcel
1999-11-01
Two possible routes are considered to arrive at a one-particle reduced density matrix formulation of electronic structure theory. In the first scheme, an extended Fock matrix H is defined that has twice the dimension of the one-particle basis set. The corresponding Green's function, defined as the upper left block of (?1-H)-1, yields the exact one-particle density matrix and energy. The poles of the Green's function are precisely the ionization potentials and electron affinities of the extended Koopmans theorem. In the second scheme, a generalized Fock equation [F(?),?]=X is derived that is satisfied by the exact non-idempotent one-particle density matrix. The antisymmetric matrix X on the right-hand side is obtained from the irreducible part of the two-particle reduced density matrix, while F is the usual Fock matrix defined using the correlated one-matrix. The generalized Fock equation is a necessary condition but does not determine ? uniquely. Alternatively, the one-matrix can be obtained from the irreducible part of the two-matrix directly, using a sum rule. The analysis leads to some additional desiderata and separability properties that may be imposed on traditional wave function based approaches. Possibilities for practical computational schemes are addressed briefly.
The nuclear matrix prepared by amine modification
Wan, Katherine M.; Nickerson, Jeffrey A.; Krockmalnic, Gabriela; Penman, Sheldon
1999-01-01
The nucleus is spatially ordered by attachments to a nonchromatin nuclear structure, the nuclear matrix. The nuclear matrix and chromatin are intimately connected and integrated structures, and so a major technical challenge in nuclear matrix research has been to remove chromatin while retaining a native nuclear matrix. Most methods for removing chromatin require first a nuclease digestion and then a salt extraction to remove cut chromatin. We have hypothesized that cut chromatin is held in place by charge interactions involving nucleosomal amino groups. We have tested this hypothesis by chemically modifying amino groups after nuclease digestion. By using this protocol, chromatin could be effectively removed at physiological ionic strength. We compared the ultrastructure and composition of this nuclear matrix preparation with the traditional high-salt nuclear matrix and with the third nuclear matrix preparation that we have developed from which chromatin is removed after extensive crosslinking. All three matrix preparations reveal internal nuclear matrix structures that are built on a network of branched filaments of about 10 nm diameter. That such different chromatin-removal protocols reveal similar principles of nuclear matrix construction increases our confidence that we are observing important architectural elements of the native structure in the living cell. PMID:9927671
The Neighbor Matrix: Generalizing the Degree Distribution
Jonathan W. Roginski; Ralucca M. Gera; Erik C. Rye
2015-10-19
The newly introduced neighborhood matrix extends the power of adjacency and distance matrices to describe the topology of graphs. The adjacency matrix enumerates which pairs of vertices share an edge and it may be summarized by the degree sequence, a list of the adjacency matrix row sums. The distance matrix shows more information, namely the length of shortest paths between vertex pairs. We introduce and explore the neighborhood matrix, which we have found to be an analog to the distance matrix what the degree sequence is to the adjacency matrix. The neighbor matrix includes the degree sequence as its first column and the sequence of all other distances in the graph up to the graph's diameter, enumerating the number of neighbors each vertex has at every distance present in the graph. We prove this matrix to contain eleven oft-used graph statistics and topological descriptors. We also provide proofs of concept for two applications that show potential utility of the neighbor matrix in comparing graphs and identifying topologically significant vertices in a graph.
Universality of Quark-Lepton Mass Matrix
Takeshi Fukuyama; Hiroyuki Nishiura
2013-01-22
The recently observed lepton mixing angle $\\theta_{13}$ of the MNS mixing matrix is well incorporated in a universal mixing hypothesis between quark and lepton sectors. This hypothesis asserts that, in the charged lepton diagonal base, all other mass matrices for up- and down-type quarks and light neutrinos are diagonalized by the same unitary matrix except for the phase elements. It is expressed as $V_{CKM}= U_{MNS}(\\delta^\\prime)^\\dagger P U_{MNS}(\\delta)$ for quark mixing matrix $V_{CKM}$ and lepton mixing matrix $U_{MNS}(\\delta)$ in the phenomenological level. Here $P$ is a diagonal phase mass matrix. $\\delta^\\prime$ is a slightly different phase parameter from the Dirac CP violating phase $\\delta=1.1\\pi$ (best fit) in the MNS lepton mixing matrix.
Thermoplastic matrix composite processing model
NASA Technical Reports Server (NTRS)
Dara, P. H.; Loos, A. C.
1985-01-01
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.
Intermetallic bonded ceramic matrix composites
Plucknett, K.P.; Tiegs, T.N.; Alexander, K.B.; Becher, P.F.; Schneibel, J.H.; Waters, S.B.; Menchhofer, P.A.
1995-07-01
A range of carbide and oxide-based cermets have been developed utilizing ductile nickel aluminide (Ni{sub 3}Al) alloy binder phases. Some of these, notably materials based upon tungsten and titanium carbides (WC and TiC respectively), offer potential as alternatives to the cermets which use cobalt binders (i.e. WC/Co). Samples have been prepared by blending commercially available Ni{sub 3}Al alloy powders with the desired ceramic phases, followed by hot-pressing. Alumina (Al{sub 2}O{sub 3}) matrix materials have also been prepared by pressurized molten alloy infiltration. The microstructure, flexure strength and fracture toughness of selected materials are discussed.
Matrix-valued Quantum Lattice Boltzmann Method
Christian B. Mendl
2015-02-23
We devise a lattice Boltzmann method (LBM) for a matrix-valued quantum Boltzmann equation, with the classical Maxwell distribution replaced by Fermi-Dirac functions. To accommodate the spin density matrix, the distribution functions become 2 x 2 matrix-valued. From an analytic perspective, the efficient, commonly used BGK approximation of the collision operator is valid in the present setting. The numerical scheme could leverage the principles of LBM for simulating complex spin systems, with applications to spintronics.
Solution of matrix equations using sparse techniques
NASA Technical Reports Server (NTRS)
Baddourah, Majdi
1994-01-01
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.
String Interactions in c=1 Matrix Model
NASA Astrophysics Data System (ADS)
de Boer, Jan; Sinkovics, Annamaria; Verlinde, Erik; Yee, Jung-Tay
2004-03-01
We study string interactions in the fermionic formulation of the c = 1 matrix model. We give a precise nonperturbative description of the rolling tachyon state in the matrix model, and discuss S-matrix elements of the c = 1 string. As a first step to study string interactions, we compute the interaction of two decaying D0-branes in terms of free fermions. This computation is compared with the string theory cylinder diagram using the rolling tachyon ZZ boundary states.
Commuting Matrix Solutions of PQCD Evolution Equations
Mehrdad Goshtasbpour; Seyed Ali Shafiei
2013-03-16
A method of obtaining parton distributions directly from data is revealed in this series. In the process, the first step would be developing appropriate matrix solutions of the evolution equations in $x$ space. A division into commuting and non-commuting matrix solutions has been made. Here, well-developed commuting matrix solutions are presented. Results for finite LO evolution match those of standard LO sets. There is a real potential of doing non-parametric data analysis.
Multiscale Modeling of Ceramic Matrix Composites
NASA Technical Reports Server (NTRS)
Bednarcyk, Brett A.; Mital, Subodh K.; Pineda, Evan J.; Arnold, Steven M.
2015-01-01
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.
Finding Nonoverlapping Substructures of a Sparse Matrix
Pinar, Ali; Vassilevska, Virginia
2005-08-11
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.
Integrated-optical approaches to matrix multiplication
NASA Technical Reports Server (NTRS)
Verber, C. M.; Kenan, R. P.
1984-01-01
The solution of matrix equations is essential to carrying out a large variety of control algorithms and to reducing certain types of data such as the output of a multispectral sensor array. Optical techniques and, in particular, integrated-optical circuits (IOC's) can provide compact, low-power devices for performing the mitrix multiplications necessary for the solution of these problems. A specific IOC for performing vector-matrix multiplication and several approaches to the design of IOC's for matrix-matrix multiplication will be discussed.
A random matrix theory of decoherence
T. Gorin; C. Pineda; H. Kohler; T. H. Seligman
2008-07-30
Random matrix theory is used to represent generic loss of coherence of a fixed central system coupled to a quantum-chaotic environment, represented by a random matrix ensemble, via random interactions. We study the average density matrix arising from the ensemble induced, in contrast to previous studies where the average values of purity, concurrence, and entropy were considered; we further discuss when one or the other approach is relevant. The two approaches agree in the limit of large environments. Analytic results for the average density matrix and its purity are presented in linear response approximation. The two-qubit system is analysed, mainly numerically, in more detail.
FUNCTIONS PRESERVING MATRIX GROUPS AND ITERATIONS FOR THE MATRIX SQUARE ROOT
Higham, Nicholas J.
FUNCTIONS PRESERVING MATRIX GROUPS AND ITERATIONS FOR THE MATRIX SQUARE ROOT NICHOLAS J. HIGHAM, D. STEVEN MACKEY, NILOUFER MACKEY, AND FRANCÂ¸OISE TISSEUR SIAM J. MATRIX ANAL. APPL. c 2005 Society? For example, if A is symplectic when is f(A) symplectic? We show that group structure is preserved precisely
The Twisted Matrix: Dream, Simulation or Hybrid?
Clark, Andy
2004-01-01
“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 of control, you don’t even know it…I was completely duped again and again ...
Singularity confinement for matrix discrete Painlevé equations
NASA Astrophysics Data System (ADS)
Cassatella-Contra, Giovanni A.; Mañas, Manuel; Tempesta, Piergiulio
2014-09-01
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.
HYGROTHERMAL AGING OF POLYIMIDE MATRIX COMPOSITE LAMINATES
Nairn, John A.
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
Risk Management using Dependency Stucture Matrix
NASA Astrophysics Data System (ADS)
Petkovi?, Ivan
2011-09-01
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.
Fabrication of hybrid ceramic matrix composites
NASA Astrophysics Data System (ADS)
Haug, S. B.; Dharani, L. R.; Carroll, D. R.
1994-03-01
The desire to improve the transverse properties and microcracking stress of unidirectional continuous fiber reinforced ceramic matrix composites has led to development of the hybrid ceramic matrix composite (HCMC). This paper discusses the techniques we used in the fabrication of HCMC specimens used for mechanical characterization.
IMPROVING SANDSTONE MATRIX STIMULATION OF OIL
Abu-Khamsin, Sidqi
IMPROVING SANDSTONE MATRIX STIMULATION OF OIL WELLS BY GAS PRECONDITIONING M. A. Aggour, M. Al, 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
The Molecules of the Cell Matrix.
ERIC Educational Resources Information Center
Weber, Klaus; Osborn, Mary
1985-01-01
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)
On Sunflowers and Matrix Multiplication Amir Shpilka
Shpilka, Amir
On Sunflowers and Matrix Multiplication Noga Alon Amir Shpilka Christopher Umans Abstract We present several variants of the sunflower conjecture of Erdos and Rado [ER60] and discuss the relations matrix multiplication algorithms. Specifically, we show that the Erdos-Rado sunflower conjecture (if true
Finding nonoverlapping substructures of a sparse matrix
Pinar, Ali; Vassilevska, Virginia
2004-08-09
Many applications of scientific computing rely on computations on sparse matrices, thus 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 non overlapping rectangular dense blocks in a sparse matrix, which has not been studied in the sparse matrix community. We show that the maximum non overlapping 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 for 2 times 2 blocks that runs in linear time in the number of nonzeros in the matrix. We discuss alternatives to rectangular blocks such as diagonal blocks and cross blocks and present complexity analysis and approximation algorithms.
7 CFR 1770.17 - Expense matrix.
Code of Federal Regulations, 2012 CFR
2012-01-01
...Agriculture 12 2012-01-01 2012-01-01 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...
7 CFR 1770.17 - Expense matrix.
Code of Federal Regulations, 2011 CFR
2011-01-01
...Agriculture 12 2011-01-01 2011-01-01 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...
7 CFR 1770.17 - Expense matrix.
Code of Federal Regulations, 2013 CFR
2013-01-01
...Agriculture 12 2013-01-01 2013-01-01 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...
7 CFR 1770.17 - Expense matrix.
Code of Federal Regulations, 2014 CFR
2014-01-01
...Agriculture 12 2014-01-01 2013-01-01 true 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...
Transfer Matrix for Partially Quenched QCD
Claude Bernard; Maarten Golterman
2010-10-31
We construct the transfer matrix for the ghost sector of partially quenched QCD. This transfer matrix is not hermitian, but we show that it is still bounded. We thus expect that all euclidean correlation functions will decay exponentially with distance (up to possible powers), and demonstrate that this is indeed the case for free ghost quarks.
7 CFR 1770.17 - Expense matrix.
Code of Federal Regulations, 2010 CFR
2010-01-01
...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...
Micromechanics of the pericellular matrix
NASA Astrophysics Data System (ADS)
Curtis, J. E.; Boehm, H.; Schmitz, C. H. J.; Spatz, J. P.
2006-03-01
In recent years, much attention has been directed towards the properties and activities of the cell surface. In particular, the coupling of the membrane to the underlying protein polymer network called the actin cortex plays an important role in many events. The other side of the cell surface is less studied, although it too has a bound polymer network comprised of gigantic cross-linked polysaccharides (sugars). Called the pericellular matrix (PCM), it is associated with many cells including fibroblasts, chondrocytes, endothelial and smooth muscle cells. Its thickness can vary from 10's of nanometers to 10 microns and it is associated with adhesion dependent events like migration and mitosis. Biologists often hypothesize that its viscoelastic properties are responsible for the modulation of cell adhesion activities. To investigate this proposal, we measure the PCM's viscoelasticity using microrheology and probe the sharpness of its edge and its mesh size. The elastic modulus of the PCM under different condition is determined, and we characterize the long, elastic cables that can be pulled from the PCM. These results are compared with an externally reconstituted model PCM on the cell surface.
Advanced Integration Matrix Education Outreach
NASA Technical Reports Server (NTRS)
Paul Heather L.
2004-01-01
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."
TRASYS form factor matrix normalization
NASA Astrophysics Data System (ADS)
Tsuyuki, Glenn T.
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.
Historical perspective of matrix metalloproteases.
Pulkoski-Gross, Ashleigh E
2015-01-01
Matrix metalloproteinases (MMPs) were identified as early as 1962. Since this seminal finding, this family of zinc-dependent endopeptidases has been studied extensively. This collective work has resulted in delineation of MMP gene and protein structures, the mechanisms of control of MMPs, the action of MMPs on both extracellular matrices and other proteins such as growth factors and cytokines, naturally-occurring mechanisms of control, and of course their role in normal physiology and their crucial roles in pathophysiology. Stemming from the discovery that MMPs contribute to arthritis, heart disease, and cancer, amongst other diseases, attempts to develop treatment strategies incorporating MMP inhibition have been undertaken. The results of these endeavours have been mediocre, resulting in few FDA-approved MMP inhibitors mostly due to the broad-spectrum nature of these early inhibitors and unwanted side effects of MMP inhibition. The future of exploitation of MMPs in disease lies in the design of more targeted inhibitors; in order to accomplish this, we must all understand the subtle differences between each MMP and their contextual roles. In this chapter, we aim to overview major topics regarding MMPs and what direction we may go in the future. PMID:25961691
Adaptive wavelet methods - Matrix-vector multiplication
NASA Astrophysics Data System (ADS)
?erná, Dana; Fin?k, Václav
2012-12-01
The design of most adaptive wavelet methods for elliptic partial differential equations follows a general concept proposed by A. Cohen, W. Dahmen and R. DeVore in [3, 4]. The essential steps are: transformation of the variational formulation into the well-conditioned infinite-dimensional l2 problem, finding of the convergent iteration process for the l2 problem and finally derivation of its finite dimensional version which works with an inexact right hand side and approximate matrix-vector multiplications. In our contribution, we shortly review all these parts and wemainly pay attention to approximate matrix-vector multiplications. Effective approximation of matrix-vector multiplications is enabled by an off-diagonal decay of entries of the wavelet stiffness matrix. We propose here a new approach which better utilize actual decay of matrix entries.
Graphical evaluation of relativistic matrix elements
NASA Technical Reports Server (NTRS)
Huang, K. N.
1978-01-01
A graphical representation of angular momentum was used to evaluate relativistic matrix elements between antisymmetrized states of many particle configurations having any number of open shells. The antisymmetrized matrix element was expanded as a sum of semisymmetrized matrix elements. The diagram representing a semisymmetrized matrix element was composed of four diagram blocks; the bra block, the ket block, the spectator block, and the interaction block. The first three blocks indicate the couplings of the two interacting configurations while the last depends on the interaction and is the replaceable component. Interaction blocks for relativistic operators and commonly used potentials were summarized in ready to use forms. A simple step by step procedure was prescribed generally for calculating antisymmetrized matrix elements of one and two particle operators.
A matrix analysis of conjugate gradient algorithms
Ashby, S.F.; Gutknecht, M.H.
1993-04-01
This paper explores the relationships between the conjugate gradient algorithms Orthodir, Orthomin, and Orthores. To facilitate this exploration, a matrix formulation for each algorithm is given. It is shown that Orthodir directly computes a Hessenberg matrix H{sub k} at step k. Orthores also computes a Hessenberg matrix, G{sub k}, which is similar to a Hessenberg matrix obtained from H{sub k} by perturbing its last column. (This perturbation vanishes at convergence.) Orthomin, on the other hand, computes a UL and LU factorization of the perturbed H{sub k} and G{sub k}, respectively. The breakdown of Orthomin and Orthores are interpreted in terms of these underlying matrix factorizations. A connection with Lanczos algorithms is also examined, as is the special case of B-normal(1) matrices (for which efficient three-term CG algorithms exist).
Gui Lu Long; Yi-Fan Zhou; Jia-Qi Jin; Yang Sun; Hai-Woong Lee
2006-04-20
We clarify different definitions of the density matrix by proposing the use of different names, the full density matrix for a single-closed quantum system, the compressed density matrix for the averaged single molecule state from an ensemble of molecules, and the reduced density matrix for a part of an entangled quantum system, respectively. We show that ensembles with the same compressed density matrix can be physically distinguished by observing fluctuations of various observables. This is in contrast to a general belief that ensembles with the same compressed density matrix are identical. Explicit expression for the fluctuation of an observable in a specified ensemble is given. We have discussed the nature of nuclear magnetic resonance quantum computing. We show that the conclusion that there is no quantum entanglement in the current nuclear magnetic resonance quantum computing experiment is based on the unjustified belief that ensembles having the same compressed density matrix are identical physically. Related issues in quantum communication are also discussed.
Lecture 13: Chain Matrix Multiplication CLRS Section 15.2
Golin, Mordecai J.
Lecture 13: Chain Matrix Multiplication CLRS Section 15.2 Revised April 17, 2003 Outline of this Lecture . Recalling matrix multiplication. . The chain matrix multiplication problem. . A dynamic programming algorithm for chain ma trix multiplication. 1 Recalling Matrix Multiplication Matrix: An n × m
Parallel basis matrix triangularisation for hyper-sparse LP problems
Hall, Julian
Parallel basis matrix triangularisation for hyper-sparse LP problems Julian Hall School of Mathematics University of Edinburgh July 4th 2007 Parallel basis matrix triangularisation for hyper-sparse LP into the basis matrix B the matrix N Parallel basis matrix triangularisation for hyper-sparse LP problems 2 #12
Decomposition methods for sparse matrix nearness problems Lieven Vandenberghe
Vandenberghe, Lieven
Decomposition methods for sparse matrix nearness problems Yifan Sun Lieven Vandenberghe Abstract We discuss three types of sparse matrix nearness problems: given a sparse symmetric matrix, find the matrix positive semidefinite matrix with sparsity pattern E. II. S is the set of sparse matrices with sparsity
The SPARAMAT Approach to Automatic Comprehension of Sparse Matrix Computations
Kessler, Christoph
The SPARAMAT Approach to Automatic Comprehension of Sparse Matrix ComputationsÂ£ Christoph W. KeÃ?ler applied to sparse matrix codes, since it allows to ab- stract e.g. from specific sparse matrix storage comprehension suitable for sparse matrix codes, and its implementation. 1 Introduction Matrix computations
Computing matrix inversion with optical Cesare Soci,1,*
Zheludev, Nikolay
Computing matrix inversion with optical networks Kan Wu,1 Cesare Soci,1,* Perry Ping Shum,1 as an analog processor to calculate matrix inversion. A 3x3 matrix is inverted as a proof- ofN matrix, the overall solving time (including setting time of the matrix elements and calculation time
[Modern polymers in matrix tablets technology].
Zimmer, ?ukasz; Kasperek, Regina; Poleszak, Ewa
2014-01-01
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
Design of tabular excavations in foliated rock: an integrated numerical
Eberhardt, Erik
. EBERHARDT*, D. STEAD , M. J. REEVES* and C. CONNORS * Department of Geological Sciences, University. The first stage in the design process is the characterization of the rock mass using both in situ of the mining process, requiring that the rock mass stability, both within the orebody and in the rock adjacent
Analyzing Tabular Requirements Specifications Using Infinite State Model Checking
-world, safety-critical sys- tems such as air traffic control systems and nuclear power plants. These formal in the requirements specifi- cations can be detected and corrected early in the develop- ment process when correcting, Santa Barbara. His research is supported in part by NSF grant CCR-0341365. 2C. Heitmeyer's research
Domino: Extracting, Comparing, and Manipulating Subsets Across Multiple Tabular Datasets.
Gratzl, Samuel; Gehlenborg, Nils; Lex, Alexander; Pfister, Hanspeter; Streit, Marc
2014-12-01
Answering questions about complex issues often requires analysts to take into account information contained in multiple interconnected datasets. A common strategy in analyzing and visualizing large and heterogeneous data is dividing it into meaningful subsets. Interesting subsets can then be selected and the associated data and the relationships between the subsets visualized. However, neither the extraction and manipulation nor the comparison of subsets is well supported by state-of-the-art techniques. In this paper we present Domino, a novel multiform visualization technique for effectively representing subsets and the relationships between them. By providing comprehensive tools to arrange, combine, and extract subsets, Domino allows users to create both common visualization techniques and advanced visualizations tailored to specific use cases. In addition to the novel technique, we present an implementation that enables analysts to manage the wide range of options that our approach offers. Innovative interactive features such as placeholders and live previews support rapid creation of complex analysis setups. We introduce the technique and the implementation using a simple example and demonstrate scalability and effectiveness in a use case from the field of cancer genomics. PMID:26356916
A new look at the nuclear matrix.
Hancock, R
2000-07-01
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
NASA Astrophysics Data System (ADS)
Haxton, Wick; Lunardini, Cecilia
2008-09-01
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.
Earthquake prediction decision and risk matrix
NASA Astrophysics Data System (ADS)
Zou, Qi-Jia
1993-08-01
The issuance of an earthquake prediction must cause widespread social responses. It is suggested and discussed in this paper that the comprehensive decision issue for earthquake prediction considering the factors of the social and economic cost. The method of matrix decision for earthquake prediction (MDEP) is proposed in this paper and it is based on the risk matrix. The goal of decision is that search the best manner issuing earthquake prediction so that minimize the total losses of economy. The establishment and calculation of the risk matrix is discussed, and the decision results taking account of economic factors and not considering the economic factors are compared by examples in this paper.
A transilient matrix for moist convection
Romps, D.; Kuang, Z.
2011-08-15
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.
Looking for a Matrix model of ABJM
Asadig Mohammed; Jeff Murugan; Horatiu Nastase
2010-05-18
Encouraged by the recent construction of fuzzy sphere solutions in the ABJM theory, we re-analyze the latter from the perspective of a Matrix-like model. In particular, we argue that a vortex solution exhibits properties of a supergraviton, while a kink represents a 2-brane. Other solutions are also consistent with the Matrix-type interpretation. We study vortex scattering and compare with graviton scattering in the massive ABJM background, however our results are inconclusive. We speculate on how to extend our results to construct a Matrix theory of ABJM.
Hybrid Textures of Neutrino Mass Matrix
S. Kaneko; H. Sawanaka; M. Tanimoto
2005-11-23
We present analyses of the sixty hybrid textures of neutrino mass matrix, which have an equality of matrix elements and one zero. These textures are possibly derived in the models with discrete flavor symmetry. Only six textures among sixty ones are excluded by the present experimental data. Since there are many textures which give similar predictions, the textures are classified based on the numerical results. The neutrinoless double beta decay is also examined in these textures. Our results suggest that there remain still rich structures of the neutrino mass matrix in the phenomenological point of view.
Anderson transition for Google matrix eigenstates
NASA Astrophysics Data System (ADS)
Zhirov, O. V.; Shepelyansky, D. L.
2015-10-01
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.
Anderson transition for Google matrix eigenstates
Zhirov, O V
2015-01-01
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.
Visual Matrix Clustering of Social Networks
Wong, Pak C.; Mackey, Patrick S.; Foote, Harlan P.; May, Richard A.
2013-07-01
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.
ENGI 9420 2.02 -Matrix Algebra Page 2.08 2.02 Summary of Matrix Algebra
George, Glyn
ENGI 9420 2.02 - Matrix Algebra Page 2.08 2.02 Summary of Matrix Algebra Some rules of matrix algebra are summarized here. The dimensions of a matrix are (# rows Ã? #columns) [in that order]. Addition - + = Scalar multiplication: The product cA of matrix A with scalar c is obtained by multiplying every element
Kim, Myung Soo
Matrix Suppression as a Guideline for Reliable Quantification of Peptides by Matrix-Assisted Laser, Daejeon 305-806, Korea ABSTRACT: We propose to divide matrix suppression in matrix- assisted laser can be accounted for by constructing the calibration curve in the form of peptide-to-matrix ion
Active Matrix OLED Test Report
NASA Technical Reports Server (NTRS)
Salazar, George
2013-01-01
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.
LEARNING TO SENSE SPARSE SIGNALS: SIMULTANEOUS SENSING MATRIX
LEARNING TO SENSE SPARSE SIGNALS: SIMULTANEOUS SENSING MATRIX AND SPARSIFYING DICTIONARY TRANSACTIONS ON IMAGE PROCESSING 1 Learning to Sense Sparse Signals: Simultaneous Sensing Matrix Terms-- Compressed Sensing, Image Patches, Overcomplete Dictionary, Sensing Projection Matrix, Sparse
Comix, a New Matrix Element Generator
Gleisberg, Tanju; Hoche, Stefan; /Durham U., IPPP
2008-09-03
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.
Plato's Fire and the Neutrino Mass Matrix
Ernest Ma
2002-11-25
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.
Breast Multiple Primary and Histology Rules Matrix
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.
The evolution of metazoan extracellular matrix
Hynes, Richard O.
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 ...
Axial grading of inert matrix fuels
Recktenwald, G. D.; Deinert, M. R.
2012-07-01
Burning actinides in an inert matrix fuel to 750 MWd/kg IHM results in a significant reduction in transuranic isotopes. However, achieving this level of burnup in a standard light water reactor would require residence times that are twice that of uranium dioxide fuels. The reactivity of an inert matrix assembly at the end of life is less than 1/3 of its beginning of life reactivity leading to undesirable radial and axial power peaking in the reactor core. Here we show that axial grading of the inert matrix fuel rods can reduce peaking significantly. Monte Carlo simulations are used to model the assembly level power distributions in both ungraded and graded fuel rods. The results show that an axial grading of uranium dioxide and inert matrix fuels with erbium can reduces power peaking by more than 50% in the axial direction. The reduction in power peaking enables the core to operate at significantly higher power. (authors)
Molecular Adhesion between Cartilage Extracellular Matrix Macromolecules
Rojas, Fredrick P.
In this study, we investigated the molecular adhesion between the major constituents of cartilage extracellular matrix, namely, the highly negatively charged proteoglycan aggrecan and the type II/IX/XI fibrillar collagen ...
Ultrastructural organization of the sperm nuclear matrix.
Santi, S; Rubbini, S; Cinti, C; Squarzoni, S; Matteucci, A; Caramelli, E; Guidotti, L; Maraldi, N M
1995-01-01
The organization of DNA-protamine complexes and their association with the nuclear matrix have been analyzed in sperm nuclei by in situ Nick Translation at the electron microscope. The data obtained indicate that the chromatin organization in sperm nuclei is maintained during the sperm condensation by means of interaction with the nuclear matrix at fixed sites. The fine structure of the sperm nucleus and sperm nuclear matrix, investigated by sectioning and replica of freeze-fractured specimens, suggests that the lamellar array observed by freeze-fracturing in the sperm nuclei, could depend on the inner matrix which presents a regular organization of globular structures involved in the maintenance of chromatin domains. PMID:11322315
Ginsparg, P.
1991-01-01
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
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.
Integrated optic vector-matrix multiplier
Watts, Michael R. (Albuquerque, NM)
2011-09-27
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.
Role of MEPE in chondrocyte matrix mineralisation
Staines, Katherine Ann
2012-11-30
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 ...
Transition Matrix Elements for Pion Photoproduction
Mohamed E. Kelabi
2007-03-20
We have obtained the transition matrix elements for pion photoproduction by considering the number of gamma matrices involved. The approach based on the most general conditions of gauge invariance, current conservation and transversality. The approach is fairly consistent with literatures.
Robustness of neutrino mass matrix predictions
NASA Astrophysics Data System (ADS)
Rodejohann, Werner; Xu, Xun-Jie
2015-10-01
We investigate the stability of neutrino mass matrix predictions on important and currently unknown observables. Those are the octant of ?23, the sign of sin ? ? and the neutrino mass ordering. Determining those unknowns is expected to be useful in order to distinguish neutrino mass models. Therefore it may be interesting to know how robust the predictions of a mass matrix for the octant of ?23 or the neutrino mass ordering are. By applying general multiplicative perturbations we explicitly quantify how probable it is that a perturbed mass matrix predicts an octant of ?23 different from the original mass matrix, or even a neutrino mass ordering different from the original one. Both the general case and an explicit flavor symmetry model are studied. We give the probabilities as a function of the smallest neutrino mass, showing that for values exceeding 0.1 eV the chance to switch the prediction quickly approaches 50%.
Matrix Models, Emergent Spacetime and Symmetry Breaking
Grosse, Harald; Steinacker, Harold; Lizzi, Fedele
2009-12-15
We discuss how a matrix model recently shown to describe emergent gravity may contain extra degrees of freedom which reproduce some characteristics of the standard model, in particular the breaking of symmetries and the correct quantum numbers of fermions.
Projective Rectification from the Fundamental Matrix
Whelan, Paul F.
exactly matches the estimation error of the Fundamental matrix. In tests the remaining perspective distortions. Pollefeys et al. [7] describe rectification as a reprojection onto a cylindrical surface in
Supermembranes and M(atrix) Theory
Hermann Nicolai; Robert Helling
1998-09-15
In these lectures, we review the D=11 supermembrane and supersymmetric matrix models at an introductory level. We also discuss some more recent developments in connection with non-perturbative string theory.
Proton decay matrix elements from lattice QCD
Cooney, Paul
2010-01-01
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 ...
Improving the precision matrix for precision cosmology
Paz, Dante J
2015-01-01
The estimation of cosmological constraints from observations of the large scale structure of the Universe, such as the power spectrum or the correlation function, requires the knowledge of the inverse of the associated covariance matrix, namely the precision matrix, $\\mathbf{\\Psi}$. In most analyses, $\\mathbf{\\Psi}$ is estimated from a limited set of mock catalogues. Depending on how many mocks are used, this estimation has an associated error which must be propagated into the final cosmological constraints. For future surveys such as Euclid and DESI, the control of this additional uncertainty requires a prohibitively large number of mock catalogues. In this work we test a novel technique for the estimation of the precision matrix, the covariance tapering method, in the context of baryon acoustic oscillation measurements. Even though this technique was originally devised as a way to speed up maximum likelihood estimations, our results show that it also reduces the impact of noisy precision matrix estimates on...
Polymer Matrix Composite Material Oxygen Compatibility
NASA Technical Reports Server (NTRS)
Owens, Tom
2001-01-01
Carbon fiber/polymer matrix composite materials look promising as a material to construct liquid oxygen (LOX) tanks. Based on mechanical impact tests the risk will be greater than aluminum, however, the risk can probably be managed to an acceptable level. Proper tank design and operation can minimize risk. A risk assessment (hazard analysis) will be used to determine the overall acceptability for using polymer matrix composite materials.
Fuel cell with electrolyte matrix assembly
Kaufman, Arthur (West Orange, NJ); Pudick, Sheldon (Sayreville, NJ); Wang, Chiu L. (Edison, NJ)
1988-01-01
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.
Fibre-Matrix Interaction in Soft Tissue
Guo, Zaoyang
2010-05-21
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.
Topological String Correlators from Matrix Models
Robert de Mello Koch; Lwazi Nkumane
2015-02-07
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.
Matrix-valued Quantum Lattice Boltzmann Method
Mendl, Christian B
2013-01-01
We develop a numerical framework for the quantum analogue of the "classical" lattice Boltzmann method (LBM), with the Maxwell-Boltzmann distribution replaced by the Fermi-Dirac function. To accommodate the spin density matrix, the distribution functions become 2x2-matrix valued. We show that the efficient, commonly used BGK approximation of the collision operator is valid in the present setting. The framework could leverage the principles of LBM for simulating complex spin systems, with applications to spintronics.
Cryogenic regenerator including sarancarbon heat conduction matrix
NASA Technical Reports Server (NTRS)
Jones, Jack A. (Inventor); Petrick, S. Walter (Inventor); Britcliffe, Michael J. (Inventor)
1989-01-01
A saran carbon matrix is employed to conduct heat through the heat storing volume of a cryogenic regenerator. When helium is adsorbed into the saran carbon matrix, the combination exhibits a volumetric specific heat much higher than previously used lead balls. A helium adsorbed saran regenerator should allow much lower refrigerator temperatures than those practically obtainable with lead based regenerators for regenerator type refrigeration systems.
Turnover of matrix proteins in mammalian mitochondria.
Huth, Walter; Rolle, Stefan; Wunderlich, Ilona
2002-01-01
In cultured hepatocytes the turnover of several mitochondrial matrix proteins (e.g. acetyl-CoA acetyltransferase) appears to be initiated by CoA-mediated, sequential transformation into CoA-modified forms. This modification favours the notion that intramitochondrial degradation by a matrix-resident ATP-dependent protease may be preceded by a specific modification by CoA. In a mitochondrial matrix fraction the MgATP-dependent decrease in anti-CoA immunoreactivity coincided with both a decrease in the anti-protein immunoreactivity of acetyl-CoA acetyltransferase and/or of 3-ketoacyl-CoA thiolase, and with the appearance of proteolytic fragments. A closer analysis of the degradation pattern revealed, however, a breakdown of the unmodified acetyl-CoA acetyltransferase and of its CoA-modified form, A1, whereas the form that is more highly modified by CoA, A2, proved to be inaccessible towards an ATP-dependent protease. In mammalian mitochondrial matrix, proteins can be degraded selectively by a matrix-resident ATP-dependent protease. The process of CoA modification results finally in the protection of matrix proteins from degradation. In cultured hepatocytes, leupeptin, an inhibitor of lysosomal proteases, did not affect the steady-state level of the mitochondrial matrix protein acetyl-CoA acetyltransferase. However, leupeptin mediated a specific accumulation of mitochondrial matrix proteins in the cytosolic fractions of hepatocytes cultured over a 24 h period. The levels of acetyl-CoA acetyltransferase, 3-ketoacyl-CoA thiolase and glutamate dehydrogenase proteins increased 1.9-, 2.0- and 2.2-fold respectively. Their status as mature, oligomeric, but enzymically inactive enzymes strongly suggests that they originate from a leakage of autophagosomes, a constituent of the non-selective autophagic/lysosomal pathway for degradation of whole mitochondria. PMID:11988101
Fibre-Matrix Interaction in Soft Tissue
NASA Astrophysics Data System (ADS)
Guo, Zaoyang
2010-05-01
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.
Semiclassical matrix elements from periodic orbits
NASA Technical Reports Server (NTRS)
Eckhardt, B.; Fishman, S.; Mueller, K.; Wintgen, D.
1992-01-01
An extension of Gutzwiller's (1967, 1969, 1970, 1971, 1990) semiclassical theory for chaotic systems that allows a determination of matrix elements in terms of classical periodic orbits. Associated zeta functions are derived. The semiclassical predictions are found to be in good agreement with Fourier transforms of quantum spectra of hydrogen in a magnetic field. Expressions for off-diagonal matrix elements are derived that are extensions of the Bohr correspondence relations for integrable systems.
Nanophosphor composite scintillator with a liquid matrix
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
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.
Micromechanical Modeling of Woven Metal Matrix Composites
NASA Technical Reports Server (NTRS)
Bednarcyk, Brett A.; Pindera, Marek-Jerzy
1997-01-01
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.
On Quark Mixings and CKM Matrix
NASA Astrophysics Data System (ADS)
Senju, H.
1991-05-01
Inspired by unique features of the preon-subpreon model, we study quark mixings and the CKM matrix. The resultant CKM matrix has very nice properties. V_{cb} =~ - V_{ts} is predicted. Our scheme has a strong possibility to explain that V_{us} and V_{cd} are remarkably large compared with other off-diagonal elements and that V_{ub} and V_{td} are much smaller than V_{cb}.
Measuring the Density Matrix by Local Addressing
Z. Kis; S. Stenholm
2003-09-08
We introduce a procedure to measure the density matrix of a material system. The density matrix is addressed locally in this scheme by applying a sequence of delayed light pulses. The procedure is based on the stimulated Raman adiabatic passage (STIRAP) technique. It is shown that a series of population measurements on the target state of the population transfer process yields unambiguous information about the populations and coherences of the addressed states, which therefore can be determined.
Temperature dependent nonlinear metal matrix laminae behavior
NASA Technical Reports Server (NTRS)
Barrett, D. J.; Buesking, K. W.
1986-01-01
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.
Nuclear matrix support of DNA replication.
Anachkova, Boyka; Djeliova, V; Russev, G
2005-12-01
In higher eukaryotic cells, DNA is tandemly arranged into 10(4) replicons that are replicated once per cell cycle during the S phase. To achieve this, DNA is organized into loops attached to the nuclear matrix. Each loop represents one individual replicon with the origin of replication localized within the loop and the ends of the replicon attached to the nuclear matrix at the bases of the loop. During late G1 phase, the replication origins are associated with the nuclear matrix and dissociated after initiation of replication in S phase. Clusters of several replicons are operated together by replication factories, assembled at the nuclear matrix. During replication, DNA of each replicon is spooled through these factories, and after completion of DNA synthesis of any cluster of replicons, the respective replication factories are dismantled and assembled at the next cluster to be replicated. Upon completion of replication of any replicon cluster, the resulting entangled loops of the newly synthesized DNA are resolved by topoisomerases present in the nuclear matrix at the sites of attachment of the loops. Thus, the nuclear matrix plays a dual role in the process of DNA replication: on one hand, it represents structural support for the replication machinery and on the other, provides key protein factors for initiation, elongation, and termination of the replication of eukaryotic DNA. PMID:16167334
Genetic Relationships Between Chondrules, Rims and Matrix
NASA Technical Reports Server (NTRS)
Huss, G. R.; Alexander, C. M. OD.; Palme, H.; Bland, P. A.; Wasson, J. T.
2004-01-01
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.
Instructive roles of extracellular matrix on autophagy.
Neill, Thomas; Schaefer, Liliana; Iozzo, Renato V
2014-08-01
Autophagy plays an essential role in maintaining an intricate balance between nutrient demands and energetic requirements during normal homeostasis. Autophagy recycles metabolic substrates from nonspecific bulk degradation of proteins and excess or damaged organelles. Recent work posits an active and dynamic signaling role for extracellular matrix-evoked autophagic regulation, that is, allosteric and independent of prevailing nutrient conditions. Several candidates, representing a diverse repertoire of matrix constituents (decorin, collagen VI, laminin ?2, endostatin, endorepellin, and kringle V), can modulate autophagic signaling pathways. Importantly, a novel principle indicates that matrix constituents can differentially modulate autophagic induction and repression via interaction with specific receptors. Most of the matrix-derived factors described here appear to control autophagy in a canonical manner but independent of nutrient deprivation. Because the molecular composition and structure of the extracellular matrix are dynamically remodeled during various physiological and pathological conditions, we propose that matrix-regulated autophagy is key for maintaining proper tissue homeostasis and disease prevention, such as cancer progression and muscular dystrophies. PMID:24976620
Method of producing a hybrid matrix fiber composite
Deteresa, Steven J. (Livermore, CA); Lyon, Richard E. (Absecon, NJ); Groves, Scott E. (Brentwood, CA)
2006-03-28
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.
INTEGRATED COI S200 - Hi-NiCalon FIBER WITH AN S200 MATRIX (POLYMER MATRIX COMPOSITE - PMC) / AETB 1
NASA Technical Reports Server (NTRS)
2003-01-01
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
INTEGRATED COI S200 - Hi-NiCalon FIBER WITH AN S200 MATRIX (POLYMER MATRIX COMPOSITE - PMC) / AETB 1
NASA Technical Reports Server (NTRS)
2003-01-01
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
Optical matrix-matrix multiplication method demonstrated by the use of a multifocus hololens
NASA Technical Reports Server (NTRS)
Liu, H. K.; Liang, Y.-Z.
1984-01-01
A method of optical matrix-matrix multiplication is presented. The feasibility of the method is also experimentally demonstrated by the use of a dichromated-gelatin multifocus holographic lens (hololens). With the specific values of matrices chosen, the average percentage error between the theoretical and experimental data of the elements of the output matrix of the multiplication of some specific pairs of 3 x 3 matrices is 0.4 percent, which corresponds to an 8-bit accuracy.
NASA Technical Reports Server (NTRS)
Johnson, W. S.
1988-01-01
Continuous fiber reinforced metal matrix composites (MMC) are projected for use in high temperature, stiffness critical parts that will be subjected to cyclic loadings. Depending on the relative fatigue behavior of the fiber and matrix, and the interface properties, the failure modes of MMC can be grouped into four catagories: (1) matrix dominated, (2) fiber dominated, (3) self-similar damage growth, and (4) fiber/matrix interfacial failures. These four types of damage are discussed and illustrated by examples. The emphasis is on the fatigue of unnotched laminates.
Auger analysis of a fiber/matrix interface in a ceramic matrix composite
NASA Technical Reports Server (NTRS)
Honecy, Frank S.; Pepper, Stephen V.
1988-01-01
Auger electron spectroscopy (AES) depth profiling was used to characterize the fiber/matrix interface of an SiC fiber, reaction bonded Si3N4 matrix composite. Depth profiles of the as received double coated fiber revealed concentration oscillations which disappeared after annealing the fiber in the environment used to fabricate the composite. After the composite was fractured, the Auger depth profiles showed that failure occurred in neither the Beta-SiC fiber body nor in the Si3N4 matrix but, concurrently, at the fiber coating/matrix interface and within the fiber coating itself.
Experimental study on mechanical behavior of fiber/matrix interface in metal matrix composite
Wang, Q.; Chiang, F.P.
1994-12-31
The technique SIEM(Speckle Interferometry with Electron Microscopy) was employed to quantitatively measure the deformation on the fiber/matrix interface in SCS-6/Ti-6-4 composite at a microscale level. The displacement field within the fiber/matrix interphase zone was determined by in-situ observation with sensitivity of 0.003({micro}m). The macro-mechanical properties were compared with micro-mechanical behavior. It is shown that the strength in the interphase zone is weaker than the matrix tensile strength. The deformation process can be characterized by the uniform deformation, interface strain concentration and debond, and matrix plastic deformation.
METCAN-PC - METAL MATRIX COMPOSITE ANALYZER
NASA Technical Reports Server (NTRS)
Murthy, P. L.
1994-01-01
High temperature metal matrix composites offer great potential for use in advanced aerospace structural applications. The realization of this potential however, requires concurrent developments in (1) a technology base for fabricating high temperature metal matrix composite structural components, (2) experimental techniques for measuring their thermal and mechanical characteristics, and (3) computational methods to predict their behavior. METCAN (METal matrix Composite ANalyzer) is a computer program developed to predict this behavior. METCAN can be used to computationally simulate the non-linear behavior of high temperature metal matrix composites (HT-MMC), thus allowing the potential payoff for the specific application to be assessed. It provides a comprehensive analysis of composite thermal and mechanical performance. METCAN treats material nonlinearity at the constituent (fiber, matrix, and interphase) level, where the behavior of each constituent is modeled accounting for time-temperature-stress dependence. The composite properties are synthesized from the constituent instantaneous properties by making use of composite micromechanics and macromechanics. Factors which affect the behavior of the composite properties include the fabrication process variables, the fiber and matrix properties, the bonding between the fiber and matrix and/or the properties of the interphase between the fiber and matrix. The METCAN simulation is performed as point-wise analysis and produces composite properties which are readily incorporated into a finite element code to perform a global structural analysis. After the global structural analysis is performed, METCAN decomposes the composite properties back into the localized response at the various levels of the simulation. At this point the constituent properties are updated and the next iteration in the analysis is initiated. This cyclic procedure is referred to as the integrated approach to metal matrix composite analysis. METCAN-PC is written in FORTRAN 77 for IBM PC series and compatible computers running MS-DOS. An 80286 machine with an 80287 math co-processor is required for execution. The executable requires at least 640K of RAM and DOS 3.1 or higher. The package includes sample executables which were compiled under Microsoft FORTRAN v. 5.1. The standard distribution medium for this program is one 5.25 inch 360K MS-DOS format diskette. The contents of the diskette are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. METCAN-PC was developed in 1992.
Estimating the Inertia Matrix of a Spacecraft
NASA Technical Reports Server (NTRS)
Acikmese, Behcet; Keim, Jason; Shields, Joel
2007-01-01
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.
Image encryption using the Sudoku matrix
NASA Astrophysics Data System (ADS)
Wu, Yue; Zhou, Yicong; Noonan, Joseph P.; Panetta, Karen; Agaian, Sos
2010-04-01
This paper introduces a new effective and lossless image encryption algorithm using a Sudoku Matrix to scramble and encrypt the image. The new algorithm encrypts an image through a three stage process. In the first stage, a reference Sudoku matrix is generated as the foundation for the encryption and scrambling processes. The image pixels' intensities are then changed by using the reference Sudoku matrix values, and then the pixels' positions are shuffled using the Sudoku matrix as a mapping process. The advantages of this method is useful for efficiently encrypting a variety of digital images, such as binary images, gray images, and RGB images without any quality loss. The security keys of the presented algorithm are the combination of the parameters in a 1D chaotic logistic map, a parameter to control the size of Sudoku Matrix and the number of iteration times desired for scrambling. The possible security key space is extremely large. The principles of the presented scheme could be applied to provide security for a variety of systems including image, audio and video systems.
Thermal stress effects in intermetallic matrix composites
NASA Technical Reports Server (NTRS)
Wright, P. K.; Sensmeier, M. D.; Kupperman, D. S.; Wadley, H. N. G.
1993-01-01
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.
Phylogenetic stochastic mapping without matrix exponentiation.
Irvahn, Jan; Minin, Vladimir N
2014-09-01
Phylogenetic stochastic mapping is a method for reconstructing the history of trait changes on a phylogenetic tree relating species/organism carrying the trait. State-of-the-art methods assume that the trait evolves according to a continuous-time Markov chain (CTMC) and works well for small state spaces. The computations slow down considerably for larger state spaces (e.g., space of codons), because current methodology relies on exponentiating CTMC infinitesimal rate matrices-an operation whose computational complexity grows as the size of the CTMC state space cubed. In this work, we introduce a new approach, based on a CTMC technique called uniformization, which does not use matrix exponentiation for phylogenetic stochastic mapping. Our method is based on a new Markov chain Monte Carlo (MCMC) algorithm that targets the distribution of trait histories conditional on the trait data observed at the tips of the tree. The computational complexity of our MCMC method grows as the size of the CTMC state space squared. Moreover, in contrast to competing matrix exponentiation methods, if the rate matrix is sparse, we can leverage this sparsity and increase the computational efficiency of our algorithm further. Using simulated data, we illustrate advantages of our MCMC algorithm and investigate how large the state space needs to be for our method to outperform matrix exponentiation approaches. We show that even on the moderately large state space of codons our MCMC method can be significantly faster than currently used matrix exponentiation methods. PMID:24918812
Phylogenetic Stochastic Mapping Without Matrix Exponentiation
Irvahn, Jan; Minin, Vladimir N.
2014-01-01
Abstract Phylogenetic stochastic mapping is a method for reconstructing the history of trait changes on a phylogenetic tree relating species/organism carrying the trait. State-of-the-art methods assume that the trait evolves according to a continuous-time Markov chain (CTMC) and works well for small state spaces. The computations slow down considerably for larger state spaces (e.g., space of codons), because current methodology relies on exponentiating CTMC infinitesimal rate matrices—an operation whose computational complexity grows as the size of the CTMC state space cubed. In this work, we introduce a new approach, based on a CTMC technique called uniformization, which does not use matrix exponentiation for phylogenetic stochastic mapping. Our method is based on a new Markov chain Monte Carlo (MCMC) algorithm that targets the distribution of trait histories conditional on the trait data observed at the tips of the tree. The computational complexity of our MCMC method grows as the size of the CTMC state space squared. Moreover, in contrast to competing matrix exponentiation methods, if the rate matrix is sparse, we can leverage this sparsity and increase the computational efficiency of our algorithm further. Using simulated data, we illustrate advantages of our MCMC algorithm and investigate how large the state space needs to be for our method to outperform matrix exponentiation approaches. We show that even on the moderately large state space of codons our MCMC method can be significantly faster than currently used matrix exponentiation methods. PMID:24918812
Inelastic deformation of metal matrix composites
NASA Technical Reports Server (NTRS)
Lissenden, C. J.; Herakovich, C. T.; Pindera, M-J.
1993-01-01
A theoretical model capable of predicting the thermomechanical response of continuously reinforced metal matrix composite laminates subjected to multiaxial loading was developed. A micromechanical model is used in conjunction with nonlinear lamination theory to determine inelastic laminae response. Matrix viscoplasticity, residual stresses, and damage to the fiber/matrix interfacial zone are explicitly included in the model. The representative cell of the micromechanical model is considered to be in a state of generalized plane strain, enabling a quasi two-dimensional analysis to be performed. Constant strain finite elements are formulated with elastic-viscoplastic constitutive equations. Interfacial debonding is incorporated into the model through interface elements based on the interfacial debonding theory originally presented by Needleman, and modified by Tvergaard. Nonlinear interfacial constitutive equations relate interfacial tractions to displacement discontinuities at the interface. Theoretical predictions are compared with the results of an experimental program conducted on silicon carbide/titanium (SiC/Ti) unidirectional, (O4), and angle-ply, (+34)(sub s), tubular specimens. Multiaxial loading included increments of axial tension, compression, torque, and internal pressure. Loadings were chosen in an effort to distinguish inelastic deformation due to damage from matrix plasticity and separate time-dependent effects from time-independent effects. Results show that fiber/matrix debonding is nonuniform throughout the composite and is a major factor in the effective response. Also, significant creep behavior occurs at relatively low applied stress levels at room temperature.
Cache oblivious storage and access heuristics for blocked matrix-matrix multiplication
Bock, Nicolas; Rubensson, Emanuel H; Niklasson, Anders M N; Challacombe, Matt; Salek, Pawel
2008-01-01
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.
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
Computing the Polar Decomposition and the Matrix Sign Decomposition in Matrix Groups
Tisseur, Francoise
MACKEY, AND FRANCÂ¸OISE TISSEUR SIAM J. MATRIX ANAL. APPL. c 2004 Society for Industrial and Applied conditions for a matrix iteration to preserve the group structure and show that a family of globally Newton iteration for computing the unitary polar factor does not preserve group structure, but we show
COMPUTING THE POLAR DECOMPOSITION AND THE MATRIX SIGN DECOMPOSITION IN MATRIX GROUPS
Higham, Nicholas J.
. HIGHAM, D. STEVEN MACKEY, NILOUFER MACKEY, AND FRANCÂ¸OISE TISSEUR SIAM J. MATRIX ANAL. APPL. c 2004 of matrices in G. We give sufficient conditions for a matrix iteration to preserve the group structure these conditions. The well-known scaled Newton iteration for computing the unitary polar factor does not preserve
Ejection of matrix-polymer clusters in matrix-assisted laser evaporation: Experimental observations
Zhigilei, Leonid V.
emission are just a few examples of the enhanced properties adopted by CNT-doped polymers presentedEjection of matrix-polymer clusters in matrix-assisted laser evaporation: Experimental observations, Charlottesville, Virginia 22904-4745 * E-mail: jfitz@virginia.edu Abstract. The morphology of polymer films
Optimization of Sparse Matrix Kernels for Data Mining
Yelick, Katherine
Optimization of Sparse Matrix Kernels for Data Mining EunÂJin Im and Katherine Yelick Computer)642Â1266 Fax: (510)642Â5775 Abstract Number: 193 #12; Optimization of Sparse Matrix Kernels for Data Mining Eun the running time is dominated by sparse matrixÂvector products. Sparse matrixÂvector multiplication on mod
Non-Iterative MAP Reconstruction Using Sparse Matrix Representations
Non-Iterative MAP Reconstruction Using Sparse Matrix Representations Guangzhi Cao*, Student Member of sparse matrix representations. Our approach is to pre-compute and store the inverse matrix required for efficiently storing and computing the required orthonormal transfor- mations, which we call a sparse-matrix
Comparative Analysis of Sparse Matrix Algorithms For Information Retrieval
Comparative Analysis of Sparse Matrix Algorithms For Information Retrieval Nazli Goharian, Ankit matrix storage formats as index structure for text collection and their corresponding sparse matrix show the results of our implementations for several sparse matrix algorithms such as Coordinate Storage
Parallel Triangle Counting and Enumeration using Matrix Algebra
matrices. By parallelizing the individual sparse matrix operations, we achieve a parallel algorithm be seen as a special case of the row-by-row implementation of sparse matrix-matrix multiplication itself triangular parts of the sparse adjacency matrix. We parallelize our algorithm using a 1D decomposition
Online Sparse Matrix Gaussian Process Regression and Vision Applications
Yang, Ming-Hsuan
Online Sparse Matrix Gaussian Process Regression and Vision Applications Ananth Ranganathan1 inference algorithm, called Online Sparse Matrix Gaussian Processes (OSMGP), and demonstrate its merits, the Gram matrix is typically sparse. Maintaining and updating the sparse Cholesky factor of the Gram matrix
48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2010 CFR
2010-10-01
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Breaking Row and Column Symmetry in Matrix Models
Flener, Pierre
problem can be modelled with a 2-d 0/1 matrix representing which cards go into which racks [8]. SymmetryBreaking Row and Column Symmetry in Matrix Models Pierre FlenerÂ´Â½Âµ , Alan M. FrischÂ´Â¾Âµ , Brahim on balanced incomplete block design (BIBD) generation. 2 Matrix models A matrix model is a constraint program
Breaking Row and Column Symmetries in Matrix Models
St Andrews, University of
with a 2-d 0/1 matrix representing which cards go into which racks (a model with a 3-d matrix is givenBreaking Row and Column Symmetries in Matrix Models Pierre Flener 1 , Alan M. Frisch 2 , Brahim occur when we have a matrix of decision variables in which rows and/or columns can be swapped. We show
Breaking Row and Column Symmetries in Matrix Models
Walsh, Toby
problem (prob031) can be modelled with a 2-d 0/1 matrix representing which cards go into which racks (aBreaking Row and Column Symmetries in Matrix Models Pierre Flener 1 , Alan M. Frisch 2 , Brahim and experimentally. #12; 2 Matrix Models and Symmetry A matrix model is a constraint program that contains one
48 CFR 2152.370 - Use of the matrix.
Code of Federal Regulations, 2014 CFR
2014-10-01
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48 CFR 2152.370 - Use of the matrix.
Code of Federal Regulations, 2013 CFR
2013-10-01
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48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2012 CFR
2012-10-01
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48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2013 CFR
2013-10-01
...2013-10-01 2013-10-01 false 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...
48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2014 CFR
2014-10-01
...2014-10-01 2014-10-01 false 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...
48 CFR 2152.370 - Use of the matrix.
Code of Federal Regulations, 2012 CFR
2012-10-01
...2012-10-01 2012-10-01 false 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...
48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2011 CFR
2011-10-01
...2011-10-01 2011-10-01 false 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...
48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Use of the matrix. 1652... EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CLAUSES AND FORMS CONTRACT CLAUSES FEHBP Clause Matrix 1652.370 Use of the matrix. (a) The matrix in this section lists the FAR and FEHBAR clauses to be used...
48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Use of the matrix. 1652... EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CLAUSES AND FORMS CONTRACT CLAUSES FEHBP Clause Matrix 1652.370 Use of the matrix. (a) The matrix in this section lists the FAR and FEHBAR clauses to be used...
48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Use of the matrix. 1652... EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CLAUSES AND FORMS CONTRACT CLAUSES FEHBP Clause Matrix 1652.370 Use of the matrix. (a) The matrix in this section lists the FAR and FEHBAR clauses to be used...
Matrix Functions and Weighted Centers for Semidefinite Programming
Zhang, Shuzhong
Matrix Functions and Weighted Centers for Semidefinite Programming Jan Brinkhuis Zhi-Quan Luo smooth matrix-valued functions, and for the class of matrix convex (or concave) functions first introduced by LÂ¨owner and Kraus in the 1930s. For a matrix monotone function, we present formulas for its
48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Use of the matrix. 1652... EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CLAUSES AND FORMS CONTRACT CLAUSES FEHBP Clause Matrix 1652.370 Use of the matrix. (a) The matrix in this section lists the FAR and FEHBAR clauses to be used...
REVIEWS OF TOPICAL PROBLEMS: An introduction to matrix superstring models
NASA Astrophysics Data System (ADS)
Zarembo, K. L.; Makeenko, Yu M.
1998-01-01
The recently developed matrix approach to the superstring concept and M-theory is introduced. The Banks-Fishler-Shenker-Susskind matrix theory, built as a supersymmetric matrix quantum mechanics, is considered. Two supersymmetric matrix models providing a non-perturbative formulation of the IIB superstring problem are discussed. Applications to non-perturbative string theory are reviewed.
48 CFR 1652.370 - Use of the matrix.
Code of Federal Regulations, 2010 CFR
2010-10-01
...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...
Thermal and mechanical behavior of metal matrix and ceramic matrix composites
NASA Technical Reports Server (NTRS)
Kennedy, John M. (editor); Moeller, Helen H. (editor); Johnson, W. S. (editor)
1990-01-01
The present conference discusses local stresses in metal-matrix composites (MMCs) subjected to thermal and mechanical loads, the computational simulation of high-temperature MMCs' cyclic behavior, an analysis of a ceramic-matrix composite (CMC) flexure specimen, and a plasticity analysis of fibrous composite laminates under thermomechanical loads. Also discussed are a comparison of methods for determining the fiber-matrix interface frictional stresses of CMCs, the monotonic and cyclic behavior of an SiC/calcium aluminosilicate CMC, the mechanical and thermal properties of an SiC particle-reinforced Al alloy MMC, the temperature-dependent tensile and shear response of a graphite-reinforced 6061 Al-alloy MMC, the fiber/matrix interface bonding strength of MMCs, and fatigue crack growth in an Al2O3 short fiber-reinforced Al-2Mg matrix MMC.
NASA Astrophysics Data System (ADS)
Liu, B.; Yoshimine, M.
1981-01-01
The symbolic matrix method which gives compact representation and efficient determination of expressions for the Hamiltonian and other matrix operators arising in configuration interaction (CI) calculations is presented. With this method, the computing and storage requirements for matrix expressions become insignificant compared to the total requirements of a CI calculation. The efficiency is achieved by taking advantage of analogies between expressions of different matrix elements to reduce drastically the number of expressions determined explicitly. The symbolic matrix method is completely general, unrestricted by the type of operators considered, or by the choice of n-particle basis. It can take full advantage of any point group symmetry, and the ordered interacting spaces to reduce the dimension of the n-particle basis. In addition, the method provides a basis for a general direct CI method which will be presented in a forthcoming paper. A comparison with the graphical unitary group approach is provided.
Electrolyte matrix for molten carbonate fuel cells
Huang, C.M.; Yuh, C.Y.
1999-02-09
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.
Membrane sorting via the extracellular matrix.
Sadeghi, Sina; Vink, Richard L C
2015-02-01
We consider the coupling between a membrane and the extracellular matrix. Computer simulations demonstrate that the latter coupling is able to sort lipids. It is assumed that membranes are elastic manifolds, and that this manifold is disrupted by the extracellular matrix. For a solid-supported membrane with an actin network on top, regions of positive curvature are induced below the actin fibers. A similar mechanism is conceivable by assuming that the proteins which connect the cytoskeleton to the membrane induce local membrane curvature. The regions of non-zero curvature exist irrespective of any phase transition the lipids themselves may undergo. For lipids that prefer certain curvature, the extracellular matrix thus provides a spatial template for the resulting lateral domain structure of the membrane. PMID:25450353
Supersymmetric matrix models and the meander problem
Makeenko, Y M; Makeenko, Yuri; Pe, Hla Win
1996-01-01
We consider matrix-model representations of the meander problem which describes, in particular, combinatorics for foldings of closed polymer chains. We introduce a supersymmetric matrix model for describing the principal meander numbers. This model is of the type proposed by Marinari and Parisi for discretizing a superstring in D=1 while the supersymmetry is realized in D=0 as a rotational symmetry between bosonic and fermionic matrices. Using non-commutative sources, we reformulate the meander problem in a Boltzmannian Fock space whose annihilation and creation operators obey the Cuntz algebra. We discuss also the relation between the matrix models describing the meander problem and the Kazakov-Migdal model on a D-dimensional lattice.
Robust elementwise estimation of a dispersion matrix.
Mehrotra, D V
1995-12-01
Most of the existing robust methods for estimating a covariance or correlation matrix involve a multivariate approach in which matrix elements are estimated via simultaneous manipulation of all variables. These methods are generally based on complex iterative algorithms and hence are rather difficult to implement. The purpose of this article is to recommend an easy to implement noniterative robust method for estimating a dispersion matrix, based on an elementwise estimation approach. Simple expressions are provided for robust estimators of variances and covariances based, in part, on a modified A-estimator of scale discussed previously by Lax (1985, Journal of the American Statistical Association 80, 736-741). A Monte Carlo study is used to compare the performance of the proposed noniterative method with that of some iterative procedures studied in the literature. A numerical example involving robust estimation of variance components is presented as an application of the proposed methodology. PMID:8589226
Electrolyte matrix for molten carbonate fuel cells
Huang, Chao M. (Danbury, CT); Yuh, Chao-Yi (New Milford, CT)
1999-01-01
A matrix 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 .mu.m to 20 .mu.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.
Decorin modulates matrix mineralization in vitro
NASA Technical Reports Server (NTRS)
Mochida, Yoshiyuki; Duarte, Wagner R.; Tanzawa, Hideki; Paschalis, Eleftherios P.; Yamauchi, Mitsuo
2003-01-01
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.
Improved high temperature resistant matrix resins
NASA Technical Reports Server (NTRS)
Chang, G. E.; Powell, S. H.; Jones, R. J.
1983-01-01
The objective was to develop organic matrix resins suitable for service at temperatures up to 644 K (700 F) and at air pressures up to 0.4 MPa (60 psia) for time durations of a minimum of 100 hours. Matrix resins capable of withstanding these extreme oxidative environmental conditions would lead to increased use of polymer matrix composites in aircraft engines and provide significant weight and cost savings. Six linear condensation, aromatic/heterocyclic polymers containing fluorinated and/or diphenyl linkages were synthesized. The thermo-oxidative stability of the resins was determined at 644 K and compressed air pressures up to 0.4 MPa. Two formulations, both containing perfluoroisopropylidene linkages in the polymer backbone structure, exhibited potential for 644 K service to meet the program objectives. Two other formulations could not be fabricated into compression molded zero defect specimens.
Google matrix analysis of directed networks
NASA Astrophysics Data System (ADS)
Ermann, Leonardo; Frahm, Klaus M.; Shepelyansky, Dima L.
2015-10-01
In the past decade modern societies have developed enormous communication and social networks. Their classification and information retrieval processing has become a formidable task for the society. Because of the rapid growth of the World Wide Web, and social and communication networks, new mathematical methods have been invented to characterize the properties of these networks in a more detailed and precise way. Various search engines extensively use such methods. It is highly important to develop new tools to classify and rank a massive amount of network information in a way that is adapted to internal network structures and characteristics. This review describes the Google matrix analysis of directed complex networks demonstrating its efficiency using various examples including the World Wide Web, Wikipedia, software architectures, 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.
The transfer matrix: a geometrical perspective
L. L. Sanchez-Soto; J. J. Monzon; A. G. Barriuso; J. F. Carinena
2012-05-07
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.
Propulsive matrix of a helical flagellum
NASA Astrophysics Data System (ADS)
Zhang, He-Peng; Liu, Bin; Bruce, Rodenborn; Harry, L. Swinney
2014-11-01
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.
Ethynylated aromatics as high temperature matrix resins
NASA Technical Reports Server (NTRS)
Hurwitz, F. I.
1987-01-01
Difunctional and trifunctional arylacetylenes were used as monomers to form thermoset matrix resin composites. Composites can be hot-pressed at 180 C to react 80 percent of the acetylene groups. Crosslinking is completed by postcuring at 350 C. The postcured resins are thermally stable to nominally 460 C in air. As a result of their high crosslink density, the matrix exhibits brittle failure when uniaxial composites are tested in tension. Failure of both uniaixial tensile and flexural specimens occurs in shear at the fiber-matrix interface. Tensile fracture stresses for 0-deg composites fabricated with 60 v/o Celion 6K graphite fiber were 827 MPa. The strain to failure was 0.5 percent. Composites fabricated with 8 harness satin Celion cloth (Fiberite 1133) and tested in tension also failed in shear at tensile stresses of 413 MPa.
Ethynylated aromatics as high temperature matrix resins
NASA Technical Reports Server (NTRS)
Hurwitz, Frances I.
1986-01-01
Difunctional and trifunctional arylacetylenes were used as monomers to form thermoset matrix resin composites. Composites can be hot pressed at 180 C to react 80 percent of the acetylene groups. Crosslinking is completed by postcuring at 350 C. The postcured resins are thermally stable to nominally 460 C in air. As a result of their high crosslink density, the matrix exhibits brittle failure when unaxial composites are tested in tension. Failure of both uniaxial tensile and flexural specimens occurs in shear at the fiber matrix interface. Tensile fracture stresses for 0 deg composites fabricated with 60 v/o Celion 6K graphite fiber were 827 MPa. The strain to failure was 0.5 percent. Composites fabricated with 8 harness satin Celion cloth (Fiberite 1133) and tested in tension also failed in shear at tensile stresses of 413 MPa.
Accelerated matrix element method with parallel computing
NASA Astrophysics Data System (ADS)
Schouten, D.; DeAbreu, A.; Stelzer, B.
2015-07-01
The matrix element method utilizes ab initio calculations of probability densities as powerful discriminants for processes of interest in experimental particle physics. The method has already been used successfully at previous and current collider experiments. However, the computational complexity of this method for final states with many particles and degrees of freedom sets it at a disadvantage compared to supervised classification methods such as decision trees, k nearest-neighbor, or neural networks. This note presents a concrete implementation of the matrix element technique using graphics processing units. Due to the intrinsic parallelizability of multidimensional integration, dramatic speedups can be readily achieved, which makes the matrix element technique viable for general usage at collider experiments.
t matrix of metallic wire structures
Zhan, T. R. Chui, S. T.
2014-04-14
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.
Google matrix analysis of directed networks
Leonardo Ermann; Klaus M. Frahm; Dima L. Shepelyansky
2015-06-19
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.
Sparse nonnegative matrix factorization with ?0-constraints
Peharz, Robert; Pernkopf, Franz
2012-01-01
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
Core filaments of the nuclear matrix
1990-01-01
The nuclear matrix is concealed by a much larger mass of chromatin, which can be removed selectively by digesting nuclei with DNase I followed by elution of chromatin with 0.25 M ammonium sulfate. This mild procedure removes chromatin almost completely and preserves nuclear matrix morphology. The complete nuclear matrix consists of a nuclear lamina with an interior matrix composed of thick, polymorphic fibers and large masses that resemble remnant nucleoli. Further extraction of the nuclear matrices of HeLa or MCF-7 cells with 2 M sodium chloride uncovered a network of core filaments. A few dark masses remained enmeshed in the filament network and may be remnants of the nuclear matrix thick fibers and nucleoli. The highly branched core filaments had diameters of 9 and 13 nm measured relative to the intermediate filaments. They may serve as the core structure around which the matrix is constructed. The core filaments retained 70% of nuclear RNA. This RNA consisted both of ribosomal RNA precursors and of very high molecular weight hnRNA with a modal size of 20 kb. Treatment with RNase A removed the core filaments. When 2 M sodium chloride was used directly to remove chromatin after DNase I digestion without a preceding 0.25 M ammonium sulfate extraction, the core filaments were not revealed. Instead, the nuclear interior was filled with amorphous masses that may cover the filaments. This reflected a requirement for a stepwise increase in ionic strength because gradual addition of sodium chloride to a final concentration of 2 M without an 0.25 M ammonium sulfate extraction uncovered core filaments. PMID:2307700
Density matrix of black hole radiation
Lasma Alberte; Ram Brustein; Andrei Khmelnitsky; A. J. M. Medved
2015-06-30
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.
Rapid measurement of the fiber's transmission matrix
NASA Astrophysics Data System (ADS)
Brüning, Robert; Flamm, Daniel; Ngcobo, Sandile S.; Forbes, Andrew; Duparré, Michael
2015-01-01
A novel fiber characterization technique is introduced that combines two holographic procedures for selective fiber-mode excitation and complete fiber-mode analysis. The fiber's transmission matrix is constructed by directly measuring the response of the excited modes in terms of the entire guided mode spectrum. By applying a spatial multiplexing scheme for the modal decomposition, the transmission matrix is rapidly determinable, whereas the amount of needed measurements is proportional to the number of guided modes. Our technique characterizes the impact of the fiber on the mode signals and enables the investigation of underlying physical effects as well as signal correction schemes.
Multifaceted role of matrix metalloproteinases (MMPs)
Singh, Divya; Srivastava, Sanjeev K.; Chaudhuri, Tapas K.; Upadhyay, Ghanshyam
2015-01-01
Matrix metalloproteinases (MMPs), a large family of calcium-dependent zinc-containing endopeptidases, are involved in the tissue remodeling and degradation of the extracellular matrix. MMPs are widely distributed in the brain and regulate various processes including microglial activation, inflammation, dopaminergic apoptosis, blood-brain barrier disruption, and modulation of ?-synuclein pathology. High expression of MMPs is well documented in various neurological disorders including Parkinson's disease (PD), Alzheimer's disease (AD), Japanese encephalitis (JE), and Glaucoma. Although potentially critical, the role of MMPs in neuronal disorders is under-investigated. The present review summarizes the role of MMPs in neurodegeneration with a particular emphasis on PD, AD, JE, and Glaucoma. PMID:25988186
Polymeric matrix materials for infrared metamaterials
Dirk, Shawn M; Rasberry, Roger D; Rahimian, Kamyar
2014-04-22
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.
Novel formulations of CKM matrix renormalization
Kniehl, Bernd A.; Sirlin, Alberto
2009-12-17
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.
Diffusion method in random matrix theory
NASA Astrophysics Data System (ADS)
Grela, Jacek
2016-01-01
We introduce a calculational tool useful in computing ratios and products of characteristic polynomials averaged over Gaussian measures with an external source. The method is based on Dyson’s Brownian motion and Grassmann/complex integration formulas for determinants. The resulting formulas are exact for finite matrix size N and form integral representations convenient for large N asymptotics. Quantities obtained by the method are interpreted as averages over standard matrix models. We provide several explicit and novel calculations with special emphasis on the ? =2 Girko-Ginibre ensembles.
More on rotations as spin matrix polynomials
NASA Astrophysics Data System (ADS)
Curtright, Thomas L.
2015-09-01
Any nonsingular function of spin j matrices always reduces to a matrix polynomial of order 2j. The challenge is to find a convenient form for the coefficients of the matrix polynomial. The theory of biorthogonal systems is a useful framework to meet this challenge. Central factorial numbers play a key role in the theoretical development. Explicit polynomial coefficients for rotations expressed either as exponentials or as rational Cayley transforms are considered here. Structural features of the results are discussed and compared, and large j limits of the coefficients are examined.
NASA Astrophysics Data System (ADS)
Asano, Yuhma; Kawai, Daisuke; Yoshida, Kentaroh
2015-06-01
We study classical chaotic motions in the Berenstein-Maldacena-Nastase (BMN) matrix model. For this purpose, it is convenient to focus upon a reduced system composed of two-coupled anharmonic oscillators by supposing an ansatz. We examine three ansätze: 1) two pulsating fuzzy spheres, 2) a single Coulomb-type potential, and 3) integrable fuzzy spheres. For the first two cases, we show the existence of chaos by computing Poincaré sections and a Lyapunov spectrum. The third case leads to an integrable system. As a result, the BMN matrix model is not integrable in the sense of Liouville, though there may be some integrable subsectors.
Lattice calculation of weak matrix elements
NASA Astrophysics Data System (ADS)
Bernard, C.; Draper, T.; Hockney, G.; Rushton, A. M.; Soni, A.
1985-12-01
We present the first results from a small (63×10) lattice of a calculation of nonleptonic weak matrix elements. The ?I=(1/2) rule is studied as a test case. For a lattice meson of mass ~=kaon mass we find a significantly enhanced ?I=(1/2) amplitude and a ?I=(3/2) amplitude compatible with zero within our statistics. The dominance of the ?I=(1/2) amplitude appears to be due to a class of graphs called the eye graphs. Qualitatively similar results are found whether or not the charm quark is integrated out ab initio. We also report preliminary results on other weak matrix elements.
Novel formulations of CKM matrix renormalization
NASA Astrophysics Data System (ADS)
Kniehl, Bernd A.; Sirlin, Alberto
2009-12-01
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.
Analytical solutions to matrix diffusion problems
Kekäläinen, Pekka
2014-10-06
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.
Simple matrix models for random Bergman metrics
Frank Ferrari; Semyon Klevtsov; Steve Zelditch
2012-04-23
Recently, the authors have proposed a new approach to the theory of random metrics, making an explicit link between probability measures on the space of metrics on a Kahler manifold and random matrix models. We consider simple examples of such models and compute the one and two-point functions of the metric. These geometric correlation functions correspond to new interesting types of matrix model correlators. We study a large class of examples and provide in particular a detailed study of the Wishart model.
Simple matrix models for random Bergman metrics
NASA Astrophysics Data System (ADS)
Ferrari, Frank; Klevtsov, Semyon; Zelditch, Steve
2012-04-01
Recently, the authors have proposed a new approach to the theory of random metrics, making an explicit link between probability measures on the space of metrics on a Kähler manifold and random matrix models. We consider simple examples of such models and study the one- and two-point functions of the metric. These geometric correlation functions correspond to new interesting types of matrix model correlators. We provide in particular a detailed study of the Wishart model, where we determine the correlation functions explicitly. We find that the random measure in this model turns out to be concentrated on the background metric in the large N limit.
General Polarization Matrix of Electromagnetic Radiation
Muhammet Ali Can; Alexander S. Shumovsky
2001-05-15
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.
Matrix laser IR-visible image converter
Lipatov, N I; Biryukov, A S
2006-04-30
A new type of a focal matrix IR-visible image converter is proposed. The pixel IR detectors of the matrix are tunable microcavities of VCSEL (vertical-cavity surface emitting laser) semiconductor microstructures. The image conversion is performed due to the displacements of highly reflecting cavity mirrors caused by thermoelastic stresses in their microsuspensions appearing upon absorption of IR radiation. Analysis of the possibilities of the converter shows that its sensitivity is 10{sup -3}-10{sup -2} K and the time response is 10{sup -4}-10{sup -3} s. These characteristics determine the practical application of the converter. (laser applications and other topics in quantum electronics)
Algebraic Geometry of Matrix Product States
Andrew Critch; Jason Morton
2014-09-10
We quantify the representational power of matrix product states (MPS) for entangled qubit systems by giving polynomial expressions in a pure quantum state's amplitudes which hold if and only if the state is a translation invariant matrix product state or a limit of such states. For systems with few qubits, we give these equations explicitly, considering both periodic and open boundary conditions. Using the classical theory of trace varieties and trace algebras, we explain the relationship between MPS and hidden Markov models and exploit this relationship to derive useful parameterizations of MPS. We make four conjectures on the identifiability of MPS parameters.
Postglacial matrix diffusion in a boulder sample
Rasilainen, K.; Suksi, J.; Kulmala, S.; Hellmuth, K.H.; Lindberg, A.
1996-08-01
A boulder sample was studied for its unusual U content. Analyses of U-series nuclides within the rock matrix perpendicular to an assumed fracture face show abrupt pulse-like concentration distributions with very low concentrations of U daughters. Both Th-230/U-234 and Pa-231/U-235 activity ratios are low, indicating recent U accumulation into the rock. Matrix diffusion is tested as a possible cause for the experimental observations. The authors assume that the diffusion process was triggered and controlled by rock expansion, strong mixing of different water types and rapid land uplift at the end phase of the last glaciation.
Polymer Matrix Composites for Propulsion Systems
NASA Technical Reports Server (NTRS)
Nettles, Alan T.
2003-01-01
The Access-to-Space study identified the requirement for lightweight structures to achieve orbit with a single-stage vehicle. Thus a task was undertaken to examine the use of polymer matrix composites for propulsion components. It was determined that the effort of this task would be to extend previous efforts with polymer matrix composite feedlines and demonstrate the feasibility of manufacturing large diameter feedlines with a complex shape and integral flanges, (i.e. all one piece with a 90 deg bend), and assess their performance under a cryogenic atmosphere.
Gravity amplitudes from a Gaussian matrix model
NASA Astrophysics Data System (ADS)
Heckman, Jonathan J.; Verlinde, Herman
2013-09-01
We reformulate MHV scattering amplitudes in 4D gauge theory and super- gravity as correlation functions of bilinear operators in a supersymmetric gaussian matrix model. The model retains the symmetries of an S 4 of radius ? and the matrix variables are represented as linear operators acting on a finite-dimensional Hilbert space. Bilinear fields of the model generate a current algebra. In the large N double scaling limit where is held fixed, there is an emergent flat 4D space-time with a built in short distance cutoff.
The pairing matrix in discrete electromagnetism
NASA Astrophysics Data System (ADS)
Auchmann, B.; Kurz, S.
2007-08-01
We introduce pairing matrices on simplicial cell complexes in discrete electromagnetism as a means to avoid the explicit construction of a topologically dual complex. Interestingly, the Finite Element Method with first-order Whitney elements — when it is looked upon from a cell-method perspective — features pairing matrices and thus an implicitly defined dual mesh. We show that the pairing matrix can be used to construct discrete energy products. In this exercise we find that different formalisms lead to equivalent matrix representations. Discrete de Rham currents are an elegant way to subsume these geometrically equivalent but formally distinct ways of defining energy-products.
Khriachtchev, Leonid; Tapio, Salla; Domanskaya, Alexandra V.; Raesaenen, Markku; Isokoski, Karoliina; Lundell, Jan
2011-03-28
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.
Matrix kernels for measures on partitions
Eugene Strahov
2008-09-10
We consider the problem of computation of the correlation functions for the z-measures with the deformation (Jack) parameters 2 or 1/2. Such measures on partitions are originated from the representation theory of the infinite symmetric group, and in many ways are similar to the ensembles of Random Matrix Theory of $\\beta=4$ or $\\beta=1$ symmetry types. For a certain class of such measures we show that correlation functions can be represented as Pfaffians including $2\\times 2$ matrix valued kernels, and compute these kernels explicitly. We also give contour integral representations for correlation kernels of closely connected measures on partitions.
Research on graphite reinforced glass matrix composites
NASA Technical Reports Server (NTRS)
Bacon, J. F.; Prewo, K. M.
1977-01-01
The results of research for the origination of graphite-fiber reinforced glass matrix composites are presented. The method selected to form the composites consisted of pulling the graphite fiber through a slurry containing powdered glass, winding up the graphite fiber and the glass it picks up on a drum, drying, cutting into segments, loading the tape segment into a graphite die, and hot pressing. During the course of the work, composites were made with a variety of graphite fibers in a glass matrix.
Zhigilei, Leonid V.
Ejection of matrix-polymer clusters in matrix-assisted laser evaporation: Coarse-grained molecular, as related to the matrix-assisted laser evaporation (MAPLE) technique for polymer film deposition. Coarse- grained description of molecular matrix and polymer molecules is used in the model, allowing for large
Reimus, Paul W; Callahan, Timothy J; Ware, S Doug; Haga, Marc J; Counce, Dale A
2007-08-15
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 ((3)HHO). 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 (D(m)/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 (D(m)/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(D(m)/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(D(m)/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. PMID:17350718
NASA Astrophysics Data System (ADS)
Reimus, Paul W.; Callahan, Timothy J.; Ware, S. Doug; Haga, Marc J.; Counce, Dale A.
2007-08-01
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.
Andrey V. Sokolov
2014-07-19
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.
Sokolov, Andrey V
2014-01-01
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.
Matrices on the Graphing Calculator Entering a Matrix with the TI-83 or TI-84 Plus matrix editor
Torres, Rodolfo
To enter a matrix on the TI-83, press Â£ Â¢ Â¡MATRX . On the TI-84, go to Â§ Â¦ Â¤ Â¥2nd MATRX, EDIT, and select Screen, go to MATRX NAMES and select the matrix you have just entered. Entering a Matrix from the homeMatrices on the Graphing Calculator Entering a Matrix with the TI-83 or TI-84 Plus matrix editor
Density-matrix quantum Monte Carlo method
NASA Astrophysics Data System (ADS)
Blunt, N. S.; Rogers, T. W.; Spencer, J. S.; Foulkes, W. M. C.
2014-06-01
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.
Matrix Elasticity Directs Stem Cell Lineage Specification
Discher, Dennis
and also for therapeu- tic uses of stem cells. INTRODUCTION Adult stem cells, as part of normalMatrix Elasticity Directs Stem Cell Lineage Specification Adam J. Engler,1,2 Shamik Sen,1,2 H. Lee.06.044 SUMMARY Microenvironments appear important in stem cell lineage specification but can be difficult
Light weight polymer matrix composite material
NASA Technical Reports Server (NTRS)
Bowles, Kenneth J. (inventor); Lowell, Carl E. (inventor)
1988-01-01
A graphite fiber reinforced polymer matrix is layed up, cured, and thermally aged at about 750 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.
CHAPTER TEN Matrix Regulation of Tumor-
Kumar, Sanjay
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
Derive Workshop Matrix Algebra and Linear Algebra.
ERIC Educational Resources Information Center
Townsley Kulich, Lisa; Victor, Barbara
This document presents the course content for a workshop that integrates the use of the computer algebra system Derive with topics in matrix and linear algebra. The first section is a guide to using Derive that provides information on how to write algebraic expressions, make graphs, save files, edit, define functions, differentiate expressions,…
Automatic Performance Tuning of Sparse Matrix Kernels
California at Berkeley, University of
BOP) Project http://www.cs.berkeley.edu/~richie/bebop James Demmel, Katherine Yelick Richard Vuduc, Shoaib with probability 1- G is n x n connectivity matrix [n 3 billion] · gij is non-zero if page i links to page j
Alternating Projection Algorithm for Toeplitz Matrix Approximation
Al-Homidan, Suliman
of Mathematical Sciences, King Fahd University of Petroleum and Minerals, Dhahran 31261, PO Box 119, Saudi Arabia the computation of proximity projection onto certain convex sets. This paper exploits this fact in constructing to a specified matrix. Some applications to signal processing and control problems are discussed. Comparative
Matrix Computations in Basic on a Microcomputer
Higham, Nicholas J.
Matrix Computations in Basic on a Microcomputer Nicholas J. Higham October 2013 MIMS EPrint: 2013. Commodore 64 Assembly Language BLAS Listing 39 Appendix D. BBC Microcomputer Assembly Language BLAS Listing 46 Appendix E. BBC Microcomputer SGEFA/SGESL Test Program 53 Appendix F. CBM Comal-80 SGEFA
Improving the precision matrix for precision cosmology
NASA Astrophysics Data System (ADS)
Paz, Dante J.; Sánchez, Ariel G.
2015-12-01
The estimation of cosmological constraints from observations of the large-scale structure of the Universe, such as the power spectrum or the correlation function, requires the knowledge of the inverse of the associated covariance matrix, namely the precision matrix, ? . In most analyses, ? is estimated from a limited set of mock catalogues. Depending on how many mocks are used, this estimation has an associated error which must be propagated into the final cosmological constraints. For future surveys such as Euclid and Dark Energy Spectroscopic Instrument, the control of this additional uncertainty requires a prohibitively large number of mock catalogues. In this work, we test a novel technique for the estimation of the precision matrix, the covariance tapering method, in the context of baryon acoustic oscillation measurements. Even though this technique was originally devised as a way to speed up maximum likelihood estimations, our results show that it also reduces the impact of noisy precision matrix estimates on the derived confidence intervals, without introducing biases on the target parameters. The application of this technique can help future surveys to reach their true constraining power using a significantly smaller number of mock catalogues.
Science Unlimited: Grades K-6 Competency Matrix.
ERIC Educational Resources Information Center
Pennsylvania State Dept. of Education, Harrisburg. Div. of Arts and Sciences.
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;…
Holographic Geometry and Noise in Matrix Theory
Craig J. Hogan; Mark G. Jackson
2009-06-02
Using Matrix Theory as a concrete example of a fundamental holographic theory, we show that the emergent macroscopic spacetime displays a new macroscopic quantum structure, holographic geometry, and a new observable phenomenon, holographic noise, with phenomenology similar to that previously derived on the basis of a quasi-monochromatic wave theory. Traces of matrix operators on a light sheet with a compact dimension of size $R$ are interpreted as transverse position operators for macroscopic bodies. An effective quantum wave equation for spacetime is derived from the Matrix Hamiltonian. Its solutions display eigenmodes that connect longitudinal separation and transverse position operators on macroscopic scales. Measurements of transverse relative positions of macroscopically separated bodies, such as signals in Michelson interferometers, are shown to display holographic nonlocality, indeterminacy and noise, whose properties can be predicted with no parameters except $R$. Similar results are derived using a detailed scattering calculation of the matrix wavefunction. Current experimental technology will allow a definitive and precise test or validation of this interpretation of holographic fundamental theories. In the latter case, they will yield a direct measurement of $R$ independent of the gravitational definition of the Planck length, and a direct measurement of the total number of degrees of freedom.
Evaluation of the Matrix Project. Interchange 77.
ERIC Educational Resources Information Center
McIvor, Gill; Moodie, Kristina
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…
Matrix product states for quantum metrology
Marcin Jarzyna; Rafal Demkowicz-Dobrzanski
2013-06-15
We demonstrate that the optimal states in lossy quantum interferometry may be efficiently simulated using low rank matrix product states. We argue that this should be expected in all realistic quantum metrological protocols with uncorrelated noise and is related to the elusive nature of the Heisenberg precision scaling in presence of decoherence.
Mueller matrix imaging ellipsometry for nanostructure metrology.
Liu, Shiyuan; Du, Weichao; Chen, Xiuguo; Jiang, Hao; Zhang, Chuanwei
2015-06-29
In order to achieve effective process control, fast, inexpensive, nondestructive and reliable nanometer scale feature measurements are extremely useful in high-volume nanomanufacturing. Among the possible techniques, optical scatterometry is relatively ideal due to its high throughput, low cost, and minimal sample damage. However, this technique is inherently limited by the illumination spot size of the instrument and the low efficiency in construction of a map of the sample over a wide area. Aiming at these issues, we introduce conventional imaging techniques to optical scatterometry and combine them with Mueller matrix ellipsometry based scatterometry, which is expected to be a powerful tool for the measurement of nanostructures in future high-volume nanomanufacturing, and propose to apply Mueller matrix imaging ellipsometry (MMIE) for nanostructure metrology. Two kinds of nanostructures were measured using an in-house developed Mueller matrix imaging ellipsometer in this work. The experimental results demonstrate that we can achieve Mueller matrix measurement and analysis for nanostructures with pixel-sized illumination spots by using MMIE. We can also efficiently construct parameter maps of the nanostructures over a wide area with pixel-sized lateral resolution by performing parallel ellipsometric analysis for all the pixels of interest. PMID:26191741
The algebras of large N matrix mechanics
Halpern, M.B.; Schwartz, C.
1999-09-16
Extending early work, we formulate the large N matrix mechanics of general bosonic, fermionic and supersymmetric matrix models, including Matrix theory: The Hamiltonian framework of large N matrix mechanics provides a natural setting in which to study the algebras of the large N limit, including (reduced) Lie algebras, (reduced) supersymmetry algebras and free algebras. We find in particular a broad array of new free algebras which we call symmetric Cuntz algebras, interacting symmetric Cuntz algebras, symmetric Bose/Fermi/Cuntz algebras and symmetric Cuntz superalgebras, and we discuss the role of these algebras in solving the large N theory. Most important, the interacting Cuntz algebras are associated to a set of new (hidden!) local quantities which are generically conserved only at large N. A number of other new large N phenomena are also observed, including the intrinsic nonlocality of the (reduced) trace class operators of the theory and a closely related large N field identification phenomenon which is associated to another set (this time nonlocal) of new conserved quantities at large N.
Nonnegative Matrix Factorization for Spectral Data Analysis
Plemmons, Robert J.
but difficult problem for tracking thousands of objects, including satellites, rocket bodies, debris, and asteroids, in orbit around the earth. In this paper we develop an effective nonnegative matrix factorization. This approximate factorization process is an active area of research in several disciplines (a Google search
A Random Matrix Model of Black Holes
Da Xu
2008-06-23
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.
Brain and CNS Histology Rules Matrix
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
Brain and CNS Multiple Primary Rules Matrix
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
Matrix vesicles: Are they anchored exosomes?
Shapiro, Irving M; Landis, William J; Risbud, Makarand V
2015-10-01
Numerous studies have documented that matrix vesicles are unique extracellular membrane-bound microparticles that serve as initial sites for mineral formation in the growth plate and most other vertebrate mineralizing tissues. Microparticle generation is not confined to hard tissues, as cells in soft tissues generate similar structures; numerous studies have shown that a common type of extracellular particle, termed an exosome, a product of the endosomal pathway, shares many characteristics of matrix vesicles. Indeed, analyses of size, morphology and lipid and protein content indicate that matrix vesicles and exosomes are homologous structures. Such a possibility impacts our understanding of the biogenesis, processing and function of matrix vesicles (exosomes) in vertebrate hard tissues and explains in part how cells control the earliest stages of mineral deposition. Moreover, since exosomes influence a spectrum of functions, including cell-cell communication, it is suggested that this type of microparticle may provide a mechanism for the transfer of signaling molecules between cells within the growth plate and thereby regulate endochondral bone development and formation. PMID:25980744
Renewal Credit Matrix CERTIFICATE RENEWAL PLAN
Kunkle, Tom
or university. 2. State Department of Education Certificate Renewal Course All certificate renewal courses mustRenewal Credit Matrix CERTIFICATE RENEWAL PLAN PROFESSIONAL DEVELOPMENT OPTIONS FOR SOUTH CAROLINA EDUCATORS Educators who are not employed in a position that requires South Carolina educator certification
ABCD Matrix Methods for Physical Optics
NASA Astrophysics Data System (ADS)
Garton, Adicus
2003-10-01
Matrix methods are a poweful and systematic approach to describing wave propogation through optical elements, and can be used to derive solutions to aspects of Gaussian beam propogation, including the paraxial wave approximation. Numerical examples coded in MathCad will be provided to demonstrate the power and utility of the approach.
The Bushido Matrix for Couple Communication
ERIC Educational Resources Information Center
Li, Chi-Sing; Lin, Yu-Fen; Ginsburg, Phil; Eckstein, Daniel
2012-01-01
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…
Emerging Educational Institutional Decision-Making Matrix
ERIC Educational Resources Information Center
Ashford-Rowe, Kevin H.; Holt, Marnie
2011-01-01
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…
Contractions, Matrix Paramatrizations, and Quantum Information
M. C. Tseng
2006-10-31
In this note, we discuss dilation-theoretic matrix parametrizations of contractions and positive matrices. These parametrizations are then applied to some problems in quantum information theory. First we establish some properties of positive maps, or entanglement witnesses. Two further applications, concerning concrete dilations of completely positive maps, in particular quantum operations, are given.
Polymer matrix electroluminescent materials and devices
Marrocco, III, Matthew L.; Motamedi, Farshad J.; Abdelrazzaq, Feras Bashir; Abdelrazzaq, legal representative, Bashir Twfiq
2012-06-26
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.
Critical state of sand matrix soils.
Marto, Aminaton; Tan, Choy Soon; Makhtar, Ahmad Mahir; Kung Leong, Tiong
2014-01-01
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
Unitarising Matrix Element + Parton Shower merging
Leif Lonnblad; Stefan Prestel
2012-12-03
We revisit the CKKW-L method for merging tree-level matrix elements with parton showers, and amend it with an add/subtract scheme to minimise dependencies on the merging scale. The scheme is constructed to, as far as possible, recover the unitary nature of the underlying parton shower, so that the inclusive cross section is retained for each jet multiplicity separately.
Random Matrix Theory at Nonzero $?$ and $T$
K. Splittorff; J. J. M. Verbaarschot
2007-04-03
We review applications of random matrix theory to QCD at nonzero temperature and chemical potential. The chiral phase transition of QCD and QCD-like theories is discussed in terms of eigenvalues of the Dirac operator. We show that for QCD at $\\mu \
Effects of Matrix Orientifolding to Two-Loop Effective Action of Bosonic IIB Matrix Model
Reiji Yoshioka
2010-09-09
We study the spacetime structures which are described by the IIB matrix model with orientifolding. Matrix orientifolding that preserves supersymmetries yields the mirror image point with respect to a four-dimensional plane for each spacetime point that corresponds to the eigenvalue of the bosonic matrix. In order to consider the upper bound on the distance between two eigenvalues in this model, we calculate the effective action for the eigenvalues up to two-loop. The eigenvalues distribute in a tubular region around the four-dimensional plane.
Determination of Matrix Diffusion Properties of Granite
Holtta, Pirkko; Siitari-Kauppi, Marja; Huittinen, Nina; Poteri, Antti
2007-07-01
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)
Probabilistic Modeling of Ceramic Matrix Composite Strength
NASA Technical Reports Server (NTRS)
Shan, Ashwin R.; Murthy, Pappu L. N.; Mital, Subodh K.; Bhatt, Ramakrishna T.
1998-01-01
Uncertainties associated with the primitive random variables such as manufacturing process (processing temperature, fiber volume ratio, void volume ratio), constituent properties (fiber, matrix and interface), and geometric parameters (ply thickness, interphase thickness) have been simulated to quantify the scatter in the first matrix cracking strength (FMCS) and the ultimate tensile strength of SCS-6/RBSN (SiC fiber (SCS-6) reinforced reaction-bonded silicon nitride composite) ceramic matrix composite laminate at room temperature. Cumulative probability distribution function for the FMCS and ultimate tensile strength at room temperature (RT) of (0)(sub 8), (0(sub 2)/90(sub 2), and (+/-45(sub 2))(sub S) laminates have been simulated and the sensitivity of primitive variables to the respective strengths have been quantified. Computationally predicted scatter of the strengths for a uniaxial laminate have been compared with those from limited experimental data. Also the experimental procedure used in the tests has been described briefly. Results show a very good agreement between the computational simulation and the experimental data. Dominating failure modes in (0)(sub 8), (0/90)(sub s) and (+/-45)(sub S) laminates have been identified. Results indicate that the first matrix cracking strength for the (0)(sub S), and (0/90)(sub S) laminates is sensitive to the thermal properties, modulus and strengths of both the fiber and matrix whereas the ultimate tensile strength is sensitive to the fiber strength and the fiber volume ratio. In the case of a (+/-45)(sub S), laminate, both the FMCS and the ultimate tensile strengths have a small scatter range and are sensitive to the fiber tensile strength as well as the fiber volume ratio.
On the Unification of Random Matrix Theories
Rupert A Small
2015-03-31
A new method involving particle diagrams is introduced and developed into a rigorous framework for carrying out embedded random matrix calculations. Using particle diagrams and the attendant methodology including loop counting it becomes possible to calculate the fourth, sixth and eighth moments of embedded ensembles in a straightforward way. The method, which will be called the method of particle diagrams, proves useful firstly by providing a means of classifying the components of moments into particle paths, or loops, and secondly by giving a simple algorithm for calculating the magnitude of combinatorial expressions prior to calculating them explicitly. By confining calculations to the limit case $m \\ll l\\to\\infty$ this in many cases provides a sufficient excuse not to calculate certain terms at all, since it can be foretold using the method of particle diagrams that they will not survive in this asymptotic regime. Applying the method of particle diagrams washes out a great deal of the complexity intrinsic to the problem, with sufficient mathematical structure remaining to yield limiting statistics for the unified phase space of random matrix theories. Finally, since the unified form of random matrix theory is essentially the set of all randomised k-body potentials, it should be no surprise that the early statistics calculated for the unified random matrix theories in some instances resemble the statistics currently being discovered for quantum spin hypergraphs and other randomised potentials on graphs [HMH05,ES14,KLW14]. This is just the beginning for studies into the field of unified random matrix theories, or embedded ensembles, and the applicability of the method of particle diagrams to a wide range of questions as well as to the more exotic symmetry classes, such as the symplectic ensembles, is still an area of open-ended research.
High-frequency matrix converter with square wave input
Carr, Joseph Alexander; Balda, Juan Carlos
2015-03-31
A device for producing an alternating current output voltage from a high-frequency, square-wave input voltage comprising, high-frequency, square-wave input a matrix converter and a control system. The matrix converter comprises a plurality of electrical switches. The high-frequency input and the matrix converter are electrically connected to each other. The control system is connected to each switch of the matrix converter. The control system is electrically connected to the input of the matrix converter. The control system is configured to operate each electrical switch of the matrix converter converting a high-frequency, square-wave input voltage across the first input port of the matrix converter and the second input port of the matrix converter to an alternating current output voltage at the output of the matrix converter.
Pendulum impact resistance of tungsten fiber/metal matrix composites.
NASA Technical Reports Server (NTRS)
Winsa, E. A.; Petrasek, D. W.
1972-01-01
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.
Optimizing Tpetra%3CU%2B2019%3Es sparse matrix-matrix multiplication routine.
Nusbaum, Kurtis Lee
2011-08-01
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.
Hepatocyte Culture in Autologous Decellularized Spleen Matrix
Gao, Rui; Wu, Wanquan; Xiang, Junxi; Lv, Yi; Zheng, Xinglong; Chen, Qian; Wang, Haohua; Wang, Bo; Liu, Zhengwen; Ma, Feng
2015-01-01
abstract Background and Aims: Using decellularized scaffold to reengineer liver tissue is a promising alternative therapy for end-stage liver diseases. Though the decellularized human liver matrix is the ideal scaffold for reconstruction of the liver theoretically, the shortage of liver donors is still an obstacle for potential clinical application. Therefore, an appropriate alternative scaffold is needed. In the present study, we used a tissue engineering approach to prepare a rat decellularized spleen matrix (DSM) and evaluate the effectiveness of this DSM for primary rat hepatocytes culture. Methods: Rat decellularized spleen matrix (DSM) was prepared by perfusion of a series of detergents through spleen vasculature. DSM was characterized by residual DNA and specific extracellular matrix distribution. Thereafter, primary rat hepatocytes were cultured in the DSM in a 3-dimensional dynamic culture system, and liver cell survival and biological functions were evaluated by comparison with 3-dimensional sandwich culture and also with cultured in decellularized liver matrix (DLM). Results: Our research found that DSM did not exhibit any cellular components, but preserved the main extracellular matrix and the intact vasculature evaluated by DNA detection, histology, immunohistochemical staining, vessel corrosion cast and upright metallurgical microscope. Moreover, the method of DSM preparation procedure was relatively simple with high success rate (100%). After seeding primary hepatocytes in DSM, the cultured hepatocytes survived inside DSM with albumin synthesis and urea secretion within 10 d. Additionally, hepatocytes in dynamic culture medium had better biological functions at day 10 than that in sandwich culture. Albumin synthesis was 85.67 ± 6.34 ?g/107cell/24h in dynamic culture in DSM compared to 62.43 ± 4.59 ?g/107cell/24h in sandwich culture (P < 0.01) and to 87.54 ± 5.25 ?g/107cell/24h in DLM culture (P > 0.05); urea release was 32.14 ± 8.62 ?g/107cell/24h in dynamic culture in DSM compared to 20.47 ± 4.98 ?g/107 cell/24h in sandwich culture (P < 0.05) and to 37.38 ± 7.29 ?g/107cell/24h cultured in DLM (P > 0.05). Conclusion: The present study demonstrates that DSM can be prepared successfully using a tissue engineering approach. The DSM is an appropriate scaffold for primary hepatocytes culture. PMID:25664568
NASA Astrophysics Data System (ADS)
Siegel, Z.; Siegel, Edward Carl-Ludwig
2011-03-01
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!!!
System Matrix Analysis for Computed Tomography Imaging
Flores, Liubov; Vidal, Vicent; Verdú, Gumersindo
2015-01-01
In practical applications of computed tomography imaging (CT), it is often the case that the set of projection data is incomplete owing to the physical conditions of the data acquisition process. On the other hand, the high radiation dose imposed on patients is also undesired. These issues demand that high quality CT images can be reconstructed from limited projection data. For this reason, iterative methods of image reconstruction have become a topic of increased research interest. Several algorithms have been proposed for few-view CT. We consider that the accurate solution of the reconstruction problem also depends on the system matrix that simulates the scanning process. In this work, we analyze the application of the Siddon method to generate elements of the matrix and we present results based on real projection data. PMID:26575482
Rolling Element Bearing Stiffness Matrix Determination (Presentation)
Guo, Y.; Parker, R.
2014-01-01
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.
Stochastic matrix description of the glass transition
NASA Astrophysics Data System (ADS)
Kerner, Richard; Naumis, Gerardo G.
2000-02-01
We present a model of the glass transition viewed as the agglomeration and growth of clusters forming a covalent network. The creation of new layers of atoms on the rims of the clusters is treated in a probabilistic way as a linear transformation (encoded in what is called a stochastic matrix ) of a vector whose components represent the probability distribution of various sites found on the rim. The asymptotic limit of the statistics of sites in the network is given by the matrix eigenvector with eigenvalue equal to one. The model reproduces the modified Gibbs-DiMarzio equation with a system parameter that is comparable to the one observed experimentally for many chalcogenide glasses. Some other features of the glass transition process, like the form of the specific heat, are also obtained.
Eigenvalues and eigenvectors of the transfer matrix
NASA Astrophysics Data System (ADS)
Cretu, Nicolae; Pop, Ioan-Mihail; Rosca, Ioan-Calin
2012-05-01
The work presents theoretical and experimental studies on the binary and ternary solid elastic systems, with the aim to give a method for the determination of the elastic constants of the materials, especially for small ceramic samples. The built-in systems contain a gauge material and the sample of interest. The idea of the work starts from the properties of the intrinsic transfer matrix of the system, which share the same kind of eigenvalues in the resonance case. By explicit computation of the intrinsic transfer matrix of the system it is possible to find the eigenvalues and eigenvectors, and finally by measuring the frequency of the system's eigenmodes it is possible to elaborate a numerical method to compute the phase velocity and consequently the elastic constant of the material. To find experimentally the frequency of the eigenmodes, we used an experimental setup based on the Laser Doppler Interferometry and a measuring chain containing preamplifiers, filters and FFT signal analyzers.
Google matrix of business process management
Abel, M
2010-01-01
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 ...
Random matrix approach to categorical data analysis.
Patil, Aashay; Santhanam, M S
2015-09-01
Correlation and similarity measures are widely used in all the areas of sciences and social sciences. Often the variables are not numbers but are instead qualitative descriptors called categorical data. We define and study similarity matrix, as a measure of similarity, for the case of categorical data. This is of interest due to a deluge of categorical data, such as movie ratings, top-10 rankings, and data from social media, in the public domain that require analysis. We show that the statistical properties of the spectra of similarity matrices, constructed from categorical data, follow random matrix predictions with the dominant eigenvalue being an exception. We demonstrate this approach by applying it to the data for Indian general elections and sea level pressures in the North Atlantic ocean. PMID:26465449
Automation of the matrix element reweighting method
P. Artoisenet; V. Lemaître; F. Maltoni; O. Mattelaer
2011-02-01
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.
Random matrix approach to categorical data analysis
NASA Astrophysics Data System (ADS)
Patil, Aashay; Santhanam, M. S.
2015-09-01
Correlation and similarity measures are widely used in all the areas of sciences and social sciences. Often the variables are not numbers but are instead qualitative descriptors called categorical data. We define and study similarity matrix, as a measure of similarity, for the case of categorical data. This is of interest due to a deluge of categorical data, such as movie ratings, top-10 rankings, and data from social media, in the public domain that require analysis. We show that the statistical properties of the spectra of similarity matrices, constructed from categorical data, follow random matrix predictions with the dominant eigenvalue being an exception. We demonstrate this approach by applying it to the data for Indian general elections and sea level pressures in the North Atlantic ocean.
Tensile properties of ceramic matrix fiber composites
Shin, D.W.; Auh, K.H.; Tanaka, Hidehiko
1995-11-01
The mechanical properties of various 2D ceramic matrix fiber composites were characterized by tension testing, using the gripping and alignment techniques developed in this work. The woven fabric composites used for the test had the basic combinations of Al{sub 2}O{sub 3} fabric/Al{sub 2}O{sub 3}, SiC fabric/SiC, and SiC monofilament uniweave fabric/SiC. Tension testing was performed with strain gauge and acoustic emission instrumentation to identify the first-matrix cracking stress and assure a valid alignment. The peak tensile stresses of these laminate composites were about one-third of the flexural strengths. The SiC monofilament uniweave fabric (14 vol%)/SiC composites showed a relatively high peak stress of 370 MPa in tension testing.
Pfaffian Expressions for Random Matrix Correlation Functions
NASA Astrophysics Data System (ADS)
Nagao, Taro
2007-12-01
It is well known that Pfaffian formulas for eigenvalue correlations are useful in the analysis of real and quaternion random matrices. Moreover the parametric correlations in the crossover to complex random matrices are evaluated in the forms of Pfaffians. In this article, we review the formulations and applications of Pfaffian formulas. For that purpose, we first present the general Pfaffian expressions in terms of the corresponding skew orthogonal polynomials. Then we clarify the relation to Eynard and Mehta's determinant formula for hermitian matrix models and explain how the evaluation is simplified in the cases related to the classical orthogonal polynomials. Applications of Pfaffian formulas to random matrix theory and other fields are also mentioned.
Matrix metalloproteinase interactions with collagen and elastin
Van Doren, Steven R.
2015-01-01
Most abundant in the extracellular matrix are collagens, joined by elastin that confers elastic recoil to the lung, aorta, and skin. These fibrils are highly resistant to proteolysis but can succumb to a minority of the matrix metalloproteinases (MMPs). Considerable inroads to understanding how such MMPs move to the susceptible sites in collagen and then unwind the triple helix of collagen monomers have been gained. The essential role in unwinding of the hemopexin-like domain of interstitial collagenases or the collagen binding domain of gelatinases is highlighted. Elastolysis is also facilitated by the collagen binding domain in the cases of MMP-2 and MMP-9, and remote exosites of the catalytic domain in the case of MMP-12. PMID:25599938
Luneburg lens and optical matrix algebra research
NASA Technical Reports Server (NTRS)
Wood, V. E.; Busch, J. R.; Verber, C. M.; Caulfield, H. J.
1984-01-01
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.
Parallel matrix multiplication on the Connection Machine
NASA Technical Reports Server (NTRS)
Tichy, Walter F.
1988-01-01
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.
Fermi matrix element with isospin breaking
P. A. M. Guichon; A. W. Thomas; K. Saito
2011-01-12
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 $10^{-4}$.
Social patterns revealed through random matrix theory
NASA Astrophysics Data System (ADS)
Sarkar, Camellia; Jalan, Sarika
2014-11-01
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.
Google matrix analysis of directed networks
Ermann, Leonardo; Shepelyansky, Dima L
2014-01-01
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...
Phase dilemma in density matrix functional theory
NASA Astrophysics Data System (ADS)
Pernal, Katarzyna; Cioslowski, Jerzy
2004-04-01
For closed-shell systems, a particular parametrization of coefficients in a configuration interaction (CI) expansion provides a convenient formulation for the search over electronic wave functions constrained by a set of natural orbitals (NOs) and the corresponding occupation numbers that are invoked in every variational construction of the density matrix functional (DMF) Vee(?) for the electron-electron repulsion energy. It produces an explicit expression for Vee in terms of the Coulomb and exchange integrals over NOs, and an idempotent matrix ?, diagonal elements of which equal the occupation numbers. At the same time, it reveals a very serious bottleneck affecting any rigorous approach to the DMF theory, namely the phase dilemma that stems from the necessity to carry out minimization over a large number of possible combinations of CI coefficient signs. While underscoring its lack of variational nature, a simple approximation for the phase factor products provides a strict derivation for the recently proposed Kollmar-Hess functional.
Decorin: a guardian from the matrix.
Neill, Thomas; Schaefer, Liliana; Iozzo, Renato V
2012-08-01
Decorin, an archetypal member of the small leucine-rich proteoglycan gene family, has a broad binding repertoire that encompasses matrix structural components, such as collagens, and growth factors, particularly those that belong to the transforming growth factor-? ligand superfamily. Within the tumor microenvironment, stromal decorin has an inherent proclivity to directly bind and down-regulate several receptor tyrosine kinases, which are often overexpressed in cancer cells. The decorin interactome commands a powerful antitumorigenic signal by potently repressing and attenuating tumor cell proliferation, survival, migration, and angiogenesis. This collection of interacting molecules also regulates key downstream signaling processes indirectly via the sequestration of growth factors or directly via the antagonism of receptor tyrosine kinases. We propose that decorin can be considered a "guardian from the matrix" because of its innate ability to oppose pro-tumorigenic cues. PMID:22735579
Extracellular matrix as target for antitumor therapy
Harisi, Revekka; Jeney, Andras
2015-01-01
The aim of the present review is to survey the accumulated knowledge on the extracellular matrix (ECM) of tumors referring to its putative utility as therapeutic target. Following the traditional observation on the extensive morphological alteration in the tumor-affected tissue, the well-documented aberrant cellular regulation indicated that ECM components have an active role in tumor progression. However, due to the diverse functions and variable expression of proteoglycans, matrix proteins, and integrins, it is rather difficult to identify a comprehensive therapeutic target among ECM components. At present, the elevated level of heparanase and the prominent expression of ?v?5 integrin are considered as promising therapeutic targets. The inhibition of glycosaminoglycan offers another promising approach in the treatment of those tumors which are stimulated by proteoglycans. It can be ascertained that a selective ECM inhibitor would be a great asset to control metastasis driven by ECM-mediated signaling. PMID:26089687
Electrophilic properties of common MALDI matrix molecules
NASA Astrophysics Data System (ADS)
Lippa, T. P.; Eustis, S. N.; Wang, D.; Bowen, K. H.
2007-11-01
The negative ion photoelectron spectra of the following MALDI matrix molecules have been measured: 3-carboxypyridine (nicotinic acid), 2,5-dihydroxybenzoic acid (DHB), 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid), 2,6-dihydroxyacetophenone (DHAP), 3-(4-hydroxy-3-methoxyphenyl)-2-propenoic acid (ferulic acid), 3-hydroxy-2-pyridinecarboxylic acid (3HPA), and 2,6-pyridinedicarboxylic acid (dipicolinic acid). Adiabatic electron affinities and vertical detachment energies were extracted from these spectra and reported. In addition, electron affinities were calculated for DHAP, ferulic acid, dipicolinic acid and sinapinic acid. Photoelectron spectra were also measured for the dimer anions of DHB and nicotinic acid and for the fragment anion in which alpha-cyano-cinnamic acid had lost a CO2 unit. Together, these results augment the database of presently available electrophilic data on common matrix molecules along with some of their dimers and fragments.
Spin Forming of Aluminum Metal Matrix Composites
NASA Technical Reports Server (NTRS)
Lee, Jonathan A.; Munafo, Paul M. (Technical Monitor)
2001-01-01
An exploratory effort between NASA-Marshall Space Flight Center (MSFC) and SpinCraft, Inc., to experimentally spin form cylinders and concentric parts from small and thin sheets of aluminum Metal Matrix Composites (MMC), successfully yielded good microstructure data and forming parameters. MSFC and SpinCraft will collaborate on the recent technical findings and develop strategy to implement this technology for NASA's advanced propulsion and airframe applications such as pressure bulkheads, combustion liner assemblies, propellant tank domes, and nose cone assemblies.
Is the quark- mixing matrix moduli symmetric?
S. Chaturvedi; Virendra Gupta
2003-11-15
If the unitary quark- mixing matrix, $V$, is moduli symmetric then it depends on three real parameters. This means that there is a relation between the four parameters needed to parametrize a general $V$. It is shown that there exists a very simple relation involving $|V_{11}|^2, |V_{33}|^2,\\orh $ and $\\oet$. This relation is compared with the present experimental data. It is concluded that a moduli symmetric $V$ is not ruled out.
Processable polyimide adhesive and matrix composite resin
NASA Technical Reports Server (NTRS)
Pratt, J. Richard (inventor); St.clair, Terry L. (inventor); Progar, Donald J. (inventor)
1990-01-01
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.
Self-Organizing Neutrino Mixing Matrix
Ernest Ma
2012-09-25
A new and novel idea for a predictive neutrino mass matrix is presented, using the non-Abelian discrete symmetry A(4) and the seesaw mechanism with only two heavy neutral fermion singlets. Given the components of the one necessarily massless neutrino eigenstate, the other two massive states are automatically generated. A realistic example is discussed with predictions of a normal hierarchy of neutrino masses and maximal CP violation.
Ceramic Matrix Composites for Rotorcraft Engines
NASA Technical Reports Server (NTRS)
Halbig, Michael C.
2011-01-01
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.
Spin-Spin Interaction In Matrix Theory
M. Barrio; R. Helling; G. Polhemus
1998-02-03
We calculate the spin dependent static force between two D0-branes in Matrix theory. Supersymmetry relates velocity dependent potentials to spin dependent potentials. The well known v^4/r^7 term is related to a theta^8/r^11 term, where theta is the relative spin of the D0-branes. We calculate this term, confirming that it is the lowest order contribution to the static potential, and find its structure consistent with supergravity.
Nanophosphor composite scintillators comprising a polymer matrix
Muenchausen, Ross Edward (Los Alamos, NM); Mckigney, Edward Allen (Los Alamos, NM); Gilbertson, Robert David (Los Alamos, NM)
2010-11-16
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.
Metal matrix composite structural panel construction
NASA Technical Reports Server (NTRS)
Mcwithey, R. R.; Royster, D. M. (inventors); Bales, T. T.
1983-01-01
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.
Matrix Product States and Quantum Phase Transitions
Heshami, K
2009-01-01
We have developed a new approach based on matrix product representations of ground states to study Quantum Phase Transitions (QPT). As confirmation of the power of our approach we have analytically analyzed the XXZ spin-one chain with uniaxial single-ion-type anisotropy and our results compare favourably with previous numerical studies. In addition, our description lets to know which part of parameters space of the Hamiltonian is most likely to be exactly solvable.
Nonequilibrium chemistry boundary layer integral matrix procedure
NASA Technical Reports Server (NTRS)
Tong, H.; Buckingham, A. C.; Morse, H. L.
1973-01-01
The development of an analytic procedure for the calculation of nonequilibrium boundary layer flows over surfaces of arbitrary catalycities is described. An existing equilibrium boundary layer integral matrix code was extended to include nonequilibrium chemistry while retaining all of the general boundary condition features built into the original code. For particular application to the pitch-plane of shuttle type vehicles, an approximate procedure was developed to estimate the nonequilibrium and nonisentropic state at the edge of the boundary layer.
Matrix Product States and Quantum Phase Transitions
K. Heshami; S. Raeisi
2009-09-16
We have developed a new approach based on matrix product representations of ground states to study Quantum Phase Transitions (QPT). As confirmation of the power of our approach we have analytically analyzed the XXZ spin-one chain with uniaxial single-ion-type anisotropy and our results compare favourably with previous numerical studies. In addition, our description lets to know which part of parameters space of the Hamiltonian is most likely to be exactly solvable.
Random matrix ensembles associated with Lax matrices
E. Bogomolny; O. Giraud; C. Schmit
2009-04-30
A method to generate new classes of random matrix ensembles is proposed. Random matrices from these ensembles are Lax matrices of classically integrable systems with a certain distribution of momenta and coordinates. The existence of an integrable structure permits to calculate the joint distribution of eigenvalues for these matrices analytically. Spectral statistics of these ensembles are quite unusual and in many cases give rigorously new examples of intermediate statistics.
Proton decay matrix elements from lattice QCD
Aoki, Yasumichi; Shintani, Eigo; Collaboration: RBC Collaboration; UKQCD Collaboration
2012-07-27
We report on the calculation of the matrix elements of nucleon to pseudoscalar decay through a three quark operator, a part of the low-energy, four-fermion, baryon-number-violating operator originating from grand unified theories. The direct calculation of the form factors using domain-wall fermions on the lattice, incorporating the u, d and s sea-quarks effects yields the results with all the relevant systematic uncertainties controlled for the first time.
Plastic matrix composites with continuous fiber reinforcement
1991-09-19
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.
A New Scaling and Squaring Algorithm for the Matrix Exponential
Higham, Nicholas J.
A New Scaling and Squaring Algorithm for the Matrix Exponential Awad H. Al-Mohy and Nicholas J989 A NEW SCALING AND SQUARING ALGORITHM FOR THE MATRIX EXPONENTIAL AWAD H. AL-MOHY AND NICHOLAS J. HIGHAM
Matrix probing, skeleton decompositions, and sparse Fourier transform
Chiu, Jiawei
2013-01-01
In this thesis, we present three different randomized algorithms that help to solve matrices, compute low rank approximations and perform the Fast Fourier Transform. Matrix probing and its conditioning When a matrix A with ...
Design, set up, and testing of a matrix acidizing apparatus
Nevito Gomez, Javier
2006-10-30
to dissolution pattern of the matrix. The standard acid treatments are HCl mixtures to dissolve carbonate minerals and HCl- HF formulations to attack those plugging minerals, mainly silicates (clays and feldspars). A matrix acidizing apparatus for conducting...
Revealing Slip Bands In A Metal-Matrix/Fiber Composite
NASA Technical Reports Server (NTRS)
Lerch, Bradley A.
1995-01-01
Experimental procedure includes heat treatments and metallographic techniques developed to facilitate studies of deformation of metal-matrix/fiber composite under stress. Reveals slip bands, indicative of plastic flow occurring in matrix during mechanical tests of specimens of composite.
Involvement of extracellular matrix constituents in breast cancer
Lochter, Andre; Bissell, Mina J
1995-06-01
It has recently been established that the extracellular matrix is required for normal functional differentiation of mammary epithelia not only in culture, but also in vivo. The mechanisms by which extracellular matrix affects differentiation, as well as the nature of extracellular matrix constituents which have major impacts on mammary gland function, have only now begun to be dissected. The intricate variety of extracellular matrix-mediated events and the remarkable degree of plasticity of extracellular matrix structure and composition at virtually all times during ontogeny, make such studies difficult. Similarly, during carcinogenesis, the extracellular matrix undergoes gross alterations, the consequences of which are not yet precisely understood. Nevertheless, an increasing amount of data suggests that the extracellular matrix and extracellular matrix-receptors might participate in the control of most, if not all, of the successive stages of breast tumors, from appearance to progression and metastasis.
Gas chromatography/matrix-isolation apparatus
Reedy, Gerald T. (411 Francis St., Bourbonnais, IL 60914)
1986-01-01
A gas-sample collection device provides matrix isolation of individual gas bands from a gas chromatographic separation and for the spectroscopic analysis of the individual sample bands. The device includes a vacuum chamber containing a rotatably supported, specular carousel having at least one reflecting surface for holding a sample deposited thereon. A gas inlet is provided for depositing a mixture of sample and matrix material on the reflecting surface which is maintained at a sufficiently low temperature to cause solidification. A first parabolic mirror directs an incident beam of electromagnetic radiation, such as in the infrared (IR) spectrum, from a source onto the sample/matrix mixture while a second parabolic mirror directs a second beam of electromagnetic radiation reflected by the specular surface to an IR spectrometer for determining the absorption spectra of the sample material deposited on the reflecting surface. The pair of off-axis parabolic mirrors having a common focal point are positioned outside of the vacuum chamber and may be displaced in combination for improved beam positioning and alignment. The carousel is provided with an aperture for each reflecting surface to facilitate accurate positioning of the incident beam relative to the gas-samples under analysis. Improved gas-sample deposition is insured by the use of a long focal length stereomicroscope positioned outside of the vacuum chamber for monitoring sample formation through a window, while the sample collector is positioned outside of the zone bounded by the incident and reflected electromagnetic beams for improved sample access and monitoring.
Advanced polymeric matrix for valvular complications.
Acharya, Gayathri; Hopkins, Richard A; Lee, Chi H
2012-05-01
Poly(L-lactic acid) (PLLA) matrix systems incorporated with poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) containing nitric oxide (NO) donors (DETA NONOate) were developed for prevention of heart valve complications through sustained and controlled release of NO. PLLA matrices were prepared using the salt leaching method and the properties and drug release profiles were characterized. For assessment of the effects of PLLA systems on the pharmacological responses and cytotoxicity, various factors, such as calcium content, alkaline phosphatase (ALP) activity, cyclic guanosine monophosphate (cGMP) expression, intercellular adhesion molecule (ICAM-1) expression and cell viability of porcine aortic valve interstitial cells (PAVICs), were evaluated. PLLA matrices embedded with PLGA- NPs demonstrated its usefulness in alleviating the calcification rate of the VICs. The cGMP levels under osteoblastic conditions significantly increased, supporting that anticalcification activity of NO is mediated through NO-cGMP signaling pathway. The level of ICAM-1 expression in cells exposed to NO was lowered, suggesting that NO has an inhibitory activity against tissue inflammation. NO releases from PLLA matrix embedded with PLGA NPs prevented valvular calcification and inflammation without causing any cytotoxic activities. PLLA matrix system loaded with NPs containing NO donors could provide a new platform for sustained and controlled delivery of NO, significantly reducing valvular complications. PMID:22337643
Full CKM matrix with lattice QCD
Okamoto, Masataka; /Fermilab
2004-12-01
The authors show that it is now possible to fully determine the CKM matrix, for the first time, using lattice QCD. |V{sub cd}|, |V{sub cs}|, |V{sub ub}|, |V{sub cb}| and |V{sub us}| are, respectively, directly determined with the lattice results for form factors of semileptonic D {yields} {pi}lv, D {yields} Klv, B {yields} {pi}lv, B {yields} Dlv and K {yields} {pi}lv decays. The error from the quenched approximation is removed by using the MILC unquenced lattice gauge configurations, where the effect of u, d and s quarks is included. The error from the ''chiral'' extrapolation (m{sub l} {yields} m{sub ud}) is greatly reduced by using improved staggered quarks. The accuracy is comparable to that of the Particle Data Group averages. In addition, |V{sub ud}|, |V{sub ts}|, |V{sub ts}| and |V{sub td}| are determined by using unitarity of the CKM matrix and the experimental result for sin (2{beta}). In this way, they obtain all 9 CKM matrix elements, where the only theoretical input is lattice QCD. They also obtain all the Wolfenstein parameters, for the first time, using lattice QCD.
Random matrix models for phase diagrams
Benoit Vanderheyden; A D Jackson
2011-10-04
We describe a random matrix approach that can provide generic and readily soluble mean-field descriptions of the phase diagram for a variety of systems ranging from QCD to high-T_c materials. Instead of working from specific models, phase diagrams are constructed by averaging over the ensemble of theories that possesses the relevant symmetries of the problem. Although approximate in nature, this approach has a number of advantages. First, it can be useful in distinguishing generic features from model-dependent details. Second, it can help in understanding the `minimal' number of symmetry constraints required to reproduce specific phase structures. Third, the robustness of predictions can be checked with respect to variations in the detailed description of the interactions. Finally, near critical points, random matrix models bear strong similarities to Ginsburg-Landau theories with the advantage of additional constraints inherited from the symmetries of the underlying interaction. These constraints can be helpful in ruling out certain topologies in the phase diagram. In this Key Issue, we illustrate the basic structure of random matrix models, discuss their strengths and weaknesses, and consider the kinds of system to which they can be applied.
Tuberculosis, Pulmonary Cavitation, and Matrix Metalloproteinases
Ong, Catherine W. M.; Elkington, Paul T.
2014-01-01
Tuberculosis (TB), a chronic infectious disease of global importance, is facing the emergence of drug-resistant strains with few new drugs to treat the infection. Pulmonary cavitation, the hallmark of established disease, is associated with very high bacillary burden. Cavitation may lead to delayed sputum culture conversion, emergence of drug resistance, and transmission of the infection. The host immunological reaction to Mycobacterium tuberculosis is implicated in driving the development of TB cavities. TB is characterized by a matrix-degrading phenotype in which the activity of proteolytic matrix metalloproteinases (MMPs) is relatively unopposed by the specific tissue inhibitors of metalloproteinases. Proteases, in particular MMPs, secreted from monocyte-derived cells, neutrophils, and stromal cells, are involved in both cell recruitment and tissue damage and may cause cavitation. MMP activity is augmented by proinflammatory chemokines and cytokines, is tightly regulated by complex signaling paths, and causes matrix destruction. MMP concentrations are elevated in human TB and are closely associated with clinical and radiological markers of lung tissue destruction. Immunomodulatory therapies targeting MMPs in preclinical and clinical trials are potential adjuncts to TB treatment. Strategies targeting patients with cavitary TB have the potential to improve cure rates and reduce disease transmission. PMID:24713029
Properties of five toughened matrix composite materials
NASA Technical Reports Server (NTRS)
Cano, Roberto J.; Dow, Marvin B.
1992-01-01
The use of toughened matrix composite materials offers an attractive solution to the problem of poor damage tolerance associated with advanced composite materials. In this study, the unidirectional laminate strengths and moduli, notched (open-hole) and unnotched tension and compression properties of quasi-isotropic laminates, and compression-after-impact strengths of five carbon fiber/toughened matrix composites, IM7/E7T1-2, IM7/X1845, G40-800X/5255-3, IM7/5255-3, and IM7/5260 have been evaluated. The compression-after-impact (CAI) strengths were determined primarily by impacting quasi-isotropic laminates with the NASA Langley air gun. A few CAI tests were also made with a drop-weight impactor. For a given impact energy, compression after impact strengths were determined to be dependent on impactor velocity. Properties and strengths for the five materials tested are compared with NASA data on other toughened matrix materials (IM7/8551-7, IM6/1808I, IM7/F655, and T800/F3900). This investigation found that all five materials were stronger and more impact damage tolerant than more brittle carbon/epoxy composite materials currently used in aircraft structures.
Polymer matrix effects on acid generation
NASA Astrophysics Data System (ADS)
Fedynyshyn, Theodore H.; Goodman, Russell B.; Roberts, Jeanette
2008-03-01
We have measured the acid generation efficiency with EUV exposure of a PAG in different polymer matrixes representing the main classes of resist polymers as well as some previously described fluoropolymers for lithographic applications. The polymer matrix was found to have a significant effect on the acid generation efficiency of the PAG studied. A linear relationship exists between the absorbance of the resist and the acid generation efficiency. A second inverse relationship exists between Dill C and aromatic content of the resist polymer. It was shown that polymer sensitization is important for acid generation with EUV exposure and the Dill C parameter can be increased by up to five times with highly absorbing non-aromatic polymers, such as non-aromatic fluoropolymers, over an ESCAP polymer. The increase in the Dill C value will lead to an up to five fold increase in resist sensitivity. It is our expectation that these insights into the nature of polymer matrix effects on acid generation could lead to increased sensitivity for EUV resists.
Research on graphite reinforced glass matrix composites
NASA Technical Reports Server (NTRS)
Prewo, K. M.; Thompson, E. R.
1980-01-01
High levels of mechanical performance in tension, flexure, fatigue, and creep loading situations of graphite fiber reinforced glass matrix composites are discussed. At test temperatures of up to 813 K it was found that the major limiting factor was the oxidative instability of the reinforcing graphite fibers. Particular points to note include the following: (1) a wide variety of graphite fibers were found to be comparable with the glass matrix composite fabrication process; (2) choice of fiber, to a large extent, controlled resultant composite performance; (3) composite fatigue performance was found to be excellent at both 300 K and 703 K; (4) composite creep and stress rupture at temperatures of up to 813 K was limited by the oxidative stability of the fiber; (5) exceptionally low values of composite thermal expansion coefficient were attributable to the dimensional stability of both matrix and fiber; and (6) component fabricability was demonstrated through the hot pressing of hot sections and brazing using glass and metal joining phases.
Polymer Matrix Composite Lines and Ducts
NASA Technical Reports Server (NTRS)
Nettles, A. T.
2001-01-01
Since composite laminates are beginning to be identified for use in reusable launch vehicle propulsion systems, a task was undertaken to assess the feasibility of making cryogenic feedlines with integral flanges from polymer matrix composite materials. An additional level of complexity was added by having the feedlines be elbow shaped. Four materials, each with a unique manufacturing method, were chosen for this program. Feedlines were to be made by hand layup (HLU) with standard autoclave cure, HLU with electron beam cure, solvent-assisted resin transfer molding (SARTM), and thermoplastic tape laying (TTL). A test matrix of fill and drain cycles with both liquid nitrogen and liquid helium, along with a heat up to 250 F, was planned for each of the feedlines. A pressurization to failure was performed on any feedlines that passed the cryogenic cycling testing. A damage tolerance subtask was also undertaken in this study. The effects of foreign object impact to the materials used was assessed by cross-sectional examination and by permeability after impact testing. At the end of the program, the manufacture of the electron beam-cured feedlines never came to fruition. All of the TTL feedlines leaked heavily before any cryogenic testing, all of the SARTM feedlines leaked heavily after one cryogenic cycle. Thus, only the HLU with autoclave cure feedlines underwent the complete test matrix. They passed the cyclic testing and were pressurized to failure.
Google matrix, dynamical attractors, and Ulam networks
NASA Astrophysics Data System (ADS)
Shepelyansky, D. L.; Zhirov, O. V.
2010-03-01
We study the properties of the Google matrix generated by a coarse-grained Perron-Frobenius operator of the Chirikov typical map with dissipation. The finite-size matrix approximant of this operator is constructed by the Ulam method. This method applied to the simple dynamical model generates directed Ulam networks with approximate scale-free scaling and characteristics being in certain features similar to those of the world wide web with approximate scale-free degree distributions as well as two characteristics similar to the web: a power-law decay in PageRank that mirrors the decay of PageRank on the world wide web and a sensitivity to the value ? in PageRank. The simple dynamical attractors play here the role of popular websites with a strong concentration of PageRank. A variation in the Google parameter ? or other parameters of the dynamical map can drive the PageRank of the Google matrix to a delocalized phase with a strange attractor where the Google search becomes inefficient.
Discovery of Conservation Laws via Matrix Search
NASA Astrophysics Data System (ADS)
Schulte, Oliver; Drew, Mark S.
One of the main goals of Discovery Science is the development and analysis of methods for automatic knowledge discovery in the natural sciences. A central area of natural science research concerns reactions: how entities in a scientific domain interact to generate new entities. Classic AI research due to Valdés-Pérez, ?ytkow, Langley and Simon has shown that many scientific discovery tasks that concern reaction models can be formalized as a matrix search. In this paper we present a method for finding conservation laws, based on two criteria for selecting a conservation law matrix: (1) maximal strictness: rule out as many unobserved reactions as possible, and (2) parsimony: minimize the L1-norm of the matrix. We provide an efficient and scalable minimization method for the joint optimization of criteria (1) and (2). For empirical evaluation, we applied the algorithm to known particle accelerator data of the type that are produced by the Large Hadron Collider in Geneva. It matches the important Standard Model of particles that physicists have constructed through decades of research: the program rediscovers Standard Model conservation laws and the corresponding particle families of baryon, muon, electron and tau number. The algorithm also discovers the correct molecular structure of a set of chemical substances.
Airway and Extracellular Matrix Mechanics in COPD
Bidan, Cécile M.; Veldsink, Annemiek C.; Meurs, Herman; Gosens, Reinoud
2015-01-01
Chronic obstructive pulmonary disease (COPD) is one of the most common lung diseases worldwide, and is characterized by airflow obstruction that is not fully reversible with treatment. Even though airflow obstruction is caused by airway smooth muscle contraction, the extent of airway narrowing depends on a range of other structural and functional determinants that impact on active and passive tissue mechanics. Cells and extracellular matrix in the airway and parenchymal compartments respond both passively and actively to the mechanical stimulation induced by smooth muscle contraction. In this review, we summarize the factors that regulate airway narrowing and provide insight into the relative contributions of different constituents of the extracellular matrix and their biomechanical impact on airway obstruction. We then review the changes in extracellular matrix composition in the airway and parenchymal compartments at different stages of COPD, and finally discuss how these changes impact airway narrowing and the development of airway hyperresponsiveness. Finally, we position these data in the context of therapeutic research focused on defective tissue repair. As a conclusion, we propose that future works should primarily target mild or early COPD, prior to the widespread structural changes in the alveolar compartment that are more characteristic of severe COPD. PMID:26696894
Analyticity and the Holographic S-Matrix
Fitzpatrick, A.Liam; Kaplan, Jared; /SLAC
2012-04-03
We derive a simple relation between the Mellin amplitude for AdS/CFT correlation functions and the bulk S-Matrix in the flat spacetime limit, proving a conjecture of Penedones. As a consequence of the Operator Product Expansion, the Mellin amplitude for any unitary CFT must be a meromorphic function with simple poles on the real axis. This provides a powerful and suggestive handle on the locality vis-a-vis analyticity properties of the S-Matrix. We begin to explore analyticity by showing how the familiar poles and branch cuts of scattering amplitudes arise from the holographic description. For this purpose we compute examples of Mellin amplitudes corresponding to 1-loop and 2-loop Witten diagrams in AdS. We also examine the flat spacetime limit of conformal blocks, implicitly relating the S-Matrix program to the Bootstrap program for CFTs. We use this connection to show how the existence of small black holes in AdS leads to a universal prediction for the conformal block decomposition of the dual CFT.
Matrix-bound phosphine in Antarctic biosphere.
Zhu, Renbin; Sun, Liguang; Kong, Deming; Geng, Jinju; Wang, Ning; Wang, Qiang; Wang, Xiaorong
2006-08-01
Phosphine (PH(3)) is a natural gaseous carrier of phosphorus in its geochemical cycles, and it might be of importance to the phosphorus balance of natural ecosystem. For the first time phosphine levels were investigated in the Earth's coldest, driest, and most southerly Antarctic biosphere. Matrix-bound phosphine (MBP) was found in sea animal guanos, ornithogenic sediments and soils. Phosphine concentrations varied with different sea animal guanos. Average phosphine concentrations in empire penguin, gentoo penguin, sea lion, skua and gull guanos were 2.54+/-1.28 ng kg(-1), 6.21+/-2.15 ng kg(-1), 9.12+/-4.66 ng kg(-1), 11.90+/-1.29 ng kg(-1) and 14.55+/-6.74 ng kg(-1), respectively. The contents of phosphorus in these various matrixes have an important effect on MBP concentrations. The levels of phosphine appeared an increasing tendency with the content of TP, IP and OP in sea animal guanos, ornithogenic sediments or soils. The correlation between PH(3) and Fe, Mn, Al in these matrixes was also analyzed and discussed. Phosphine showed an obviously positive correlation with Fe in sea animal guanos. However, excessively high Fe, Al and Mn may inhibit the formation of PH(3) in the ornithogenic soils or sediments in the Antarctic biosphere. PMID:16504242
Extracellular matrix remodelling in human diabetic neuropathy
Hill, Rebecca
2009-01-01
The extracellular matrix of peripheral nerve plays a vital role in terms of normal nerve fibre function and also in the regenerative response following nerve injury. Nerve fibre loss is a major feature of diabetic neuropathy; however, the regenerative response is limited and this may be associated with changes in the composition of the extracellular matrix. Glycoproteins and collagens are major components of the extracellular matrix and are known to be important in terms of axonal growth. This work has therefore examined whether changes in the expression of two major glycoproteins, laminin and tenascin, and three collagen types (IV, V and VI) occur in the endoneurial and perineurial connective tissue compartments of human diabetic nerve. Despite being known to have a positive effect in terms of axonal growth, laminin levels were not elevated in the diabetic nerves. However, the pattern of tenascin expression did differ between the two groups being found in association with axon myelin units in the diabetic samples only. The pattern of collagen IV expression was the same in both tissue groups and was not found to be up-regulated. However, levels of collagen V and VI were both significantly increased in the endoneurium and for collagen VI also in the perineurium. PMID:19207983
Matrix elasticity directs stem cell lineage specification
NASA Astrophysics Data System (ADS)
Discher, Dennis
2010-03-01
Adhesion of stem cells - like most cells - is not just a membrane phenomenon. Most tissue cells need to adhere to a ``solid'' for viability, and over the last decade it has become increasingly clear that the physical ``elasticity'' of that solid is literally ``felt'' by cells. Here we show that Mesenchymal Stem Cells (MSCs) specify lineage and commit to phenotypes with extreme sensitivity to the elasticity typical of tissues [1]. In serum only media, soft matrices that mimic brain appear neurogenic, stiffer matrices that mimic muscle are myogenic, and comparatively rigid matrices that mimic collagenous bone prove osteogenic. Inhibition of nonmuscle myosin II activity blocks all elasticity directed lineage specification, which indicates that the cytoskeleton pulls on matrix through adhesive attachments. Results have significant implications for `therapeutic' stem cells and have motivated development of a proteomic-scale method to identify mechano-responsive protein structures [2] as well as deeper physical studies of matrix physics [3] and growth factor pathways [4]. [4pt] [1] A. Engler, et al. Matrix elasticity directs stem cell lineage specification. Cell (2006).[0pt] [2] C.P. Johnson, et al. Forced unfolding of proteins within cells. Science (2007).[0pt] [3] A.E.X. Brown, et al. Multiscale mechanics of fibrin polymer: Gel stretching with protein unfolding and loss of water. Science (2009).[0pt] [4] D.E. Discher, et al. Growth factors, matrices, and forces combine and control stem cells. Science (2009).
NASA Astrophysics Data System (ADS)
Martin, Tyler; Jayaraman, Arthi
2014-03-01
The morphology of materials consisting of homopolymer grafted particles in a homopolymer matrix is driven by the features of the composite, namely graft and matrix chain lengths and grafting density, which drive wetting/dewetting of the grafted layer. In our previous work, we showed that polydisperse grafted polymers stabilize the dispersed morphology of homopolymer grafted nanoparticles in a chemically identical homopolymer matrix, due to improved wetting of the polydisperse grafted layer by the monodisperse matrix. Here, we present our computational work showing the effect of polydispersity in matrix polymers. Specifically, in a bidisperse matrix, the short matrix chains preferentially wet the monodisperse grafted layer (at high grafting density) more than the long matrix chains. Additionally, this preferential wetting of the grafted layer by the short matrix chains is driven by the ratio of the long chain to short chain lengths, or the bidispersity index. Despite improved wetting of the grafted layer by the short matrix chains, the bidisperse matrix only slightly improves grafted particle dispersion in the matrix due to competing depletion-like attractive interactions induced by the long matrix chains.
Conversion of a Rhotrix to a "Coupled Matrix"
ERIC Educational Resources Information Center
Sani, B.
2008-01-01
In this note, a method of converting a rhotrix to a special form of matrix termed a "coupled matrix" is proposed. The special matrix can be used to solve various problems involving n x n and (n - 1) x (n - 1) matrices simultaneously.
Matrix String Theory As A Generalized Quantum Theory
Djordje Minic
1997-05-16
Matrix String Theory of Banks, Fischler, Shenker and Susskind can be understood as a generalized quantum theory (provisionally named "quansical" theory) which differs from Adler's generalized trace quantum dynamics. The effective Matrix String Theory Hamiltonian is constructed in a particular fermionic realization of Matrix String Theory treated as an example of "quansical" theory.
Some Noncommutative Matrix Algebras Arising in the Bispectral Problem
NASA Astrophysics Data System (ADS)
Grünbaum, F. Alberto
2014-07-01
I revisit the so called ''bispectral problem'' introduced in a joint paper with Hans Duistermaat a long time ago, allowing now for the differential operators to have matrix coefficients and for the eigenfunctions, and one of the eigenvalues, to be matrix valued too. In the last example we go beyond this and allow both eigenvalues to be matrix valued.
Parallel basis matrix triangularisation for hyper-sparse LP problems
Hall, Julian
Parallel basis matrix triangularisation for hyper-sparse LP problems Julian Hall School of Mathematics University of Edinburgh September 14th 2007 Parallel basis matrix triangularisation for hyper-sparse triangularisation scheme Â· Results Parallel basis matrix triangularisation for hyper-sparse LP problems 1 #12
Applicability of Automatic Program Comprehension to Sparse Matrix Computations
Kessler, Christoph
Applicability of Automatic Program Comprehension to Sparse Matrix Computations Christoph W. KeÃ?ler and performance preÂ diction. We show how this approach can be generalized to sparse matrix codes. Program a speculative program comprehension and parallelization method suitable for sparse matrix codes. Only where
FAST RECONSTRUCTION ALGORITHMS FOR OPTICAL TOMOGRAPHY USING SPARSE MATRIX REPRESENTATIONS
FAST RECONSTRUCTION ALGORITHMS FOR OPTICAL TOMOGRAPHY USING SPARSE MATRIX REPRESENTATIONS Guangzhi source coding techniques can be used to store the large and non-sparse matrix by apply- ing a wavelet techniques can be used to store the large and non-sparse matrix by applying appropriate orthonormal
Parallel basis matrix triangularisation for hyper-sparse LP problems
Hall, Julian
Parallel basis matrix triangularisation for hyper-sparse LP problems Julian Hall School of Mathematics University of Edinburgh July 4th 2007 Parallel basis matrix triangularisation for hyper-sparse LP Â· Results serial simulation parallel implementation Parallel basis matrix triangularisation for hyper-sparse
Sparse Matrix Libraries in C++ for High Performance Architectures
Dongarra, Jack
Sparse Matrix Libraries in C++ for High Performance Architectures Jack Dongarraxz, Andrew Lumsdaine ori- ented design allowsthe samedrivingcode to be used for various sparse matrix formats, thus addressing many of the di culties encountered with the typi- cal approach to sparse matrix libraries. We also
Highly Scalable Parallel Algorithms for Sparse Matrix Factorization
Karypis, George
Highly Scalable Parallel Algorithms for Sparse Matrix Factorization Anshul Gupta George Karypis/kumar}@cs.umn.edu Abstract In this paper, we describe scalable parallel algorithms for sparse matrix factorization, analyze than any previously known parallel formulation of sparse matrix factorization. Although, in this paper
Enterprise Text Processing: A Sparse Matrix Approach Nazli Goharian
Enterprise Text Processing: A Sparse Matrix Approach Nazli Goharian Illinois Institute the application of sparse matrix-vector multiplication algorithms for text storage and retrieval as a means of supporting efficient and accurate text processing. As many parallel sparse matrix-vector multiplication
Online Robust PCA Online Sparse + Low-Rank Matrix Recovery
Vaswani, Namrata
Online Robust PCA or Online Sparse + Low-Rank Matrix Recovery Namrata Vaswani Dept. of Electrical Sparse Matrix Recovery Online Robust PCA Recovery from incomplete data: the question In many applications Robust PCA 2/53 #12;Online Sparse Matrix Recovery Online Robust PCA Recovery from incomplete data