scholarly journals A Tensor Decomposition Algorithm for Large ODEs with Conservation Laws

2019 ◽  
Vol 19 (1) ◽  
pp. 23-38 ◽  
Author(s):  
Sergey V. Dolgov

AbstractWe propose an algorithm for solution of high-dimensional evolutionary equations (ODEs and discretized time-dependent PDEs) in the Tensor Train (TT) decomposition, assuming that the solution and the right-hand side of the ODE admit such a decomposition with a low storage. A linear ODE, discretized via one-step or Chebyshev differentiation schemes, turns into a large linear system. The tensor decomposition allows to solve this system for several time points simultaneously using an extension of the Alternating Least Squares algorithm. This method computes a reduced TT model of the solution, but in contrast to traditional offline-online reduction schemes, solving the original large problem is never required. Instead, the method solves a sequence of reduced Galerkin problems, which can be set up efficiently due to the TT decomposition of the right-hand side. The reduced system allows a fast estimation of the time discretization error, and hence adaptation of the time steps. Besides, conservation laws can be preserved exactly in the reduced model by expanding the approximation subspace with the generating vectors of the linear invariants and correction of the Euclidean norm. In numerical experiments with the transport and the chemical master equations, we demonstrate that the new method is faster than traditional time stepping and stochastic simulation algorithms, whereas the invariants are preserved up to the machine precision irrespectively of the TT approximation accuracy.

1947 ◽  
Vol 67 ◽  
pp. 31-33 ◽  
Author(s):  
R. J. H. Jenkins

1. A Bronze statue of Athena, armed, stood in the Forum of Constantine at Constantinople. This fact is witnessed by three well-known passages:(a) Arethas, bishop of Caesareia (ninth to tenth centuries), commenting on a passage of Aristeides, wrote: ‘I believe this (i.e., the Pheidian χαλκῆ Ἀθηνᾶ of Aristeides, Κατὰ τῶν Ἐξορχουμένων, p. 408) is the one set up in the Forum of Constantine, at the porch of the council-chamber, or senate, as they call it now; facing it, on the right-hand side of the porch as you go in, is Thetis, the ⟨mother⟩ of Achilles, with a crown of crabs. The common folk of to-day call the Athena “Earth” and Thetis “Sea”, being misled by the marine monsters on her head.’ (Cf. Kougeas in Laographia IV, 1913, 240, 241.)(b) Cedrenus (eleventh to twelfth centuries), after a note on the senate on the north side of the Forum, continues: ‘On the open square of the Forum stand two statues; to the west, that of Athena of Lindus, wearing a helmet and the monstrous Gorgon's head and snakes entwined about her neck (for so the ancients used to represent her image); and to the east, Amphitrite, with crabs' claws on her temples, which was also brought from Rhodes.’ (Cedrenus, ed. Bonn., I, p. 565; cf. Kougeas, loc. cit. sup.)


1977 ◽  
Vol 34 (3) ◽  
pp. 294-298
Author(s):  
Erik Routley

“Stephen, full of grace and power, did great wonders and signs among the people. Then some of those who belonged to the synagogue of the Freedmen… arose and disputed with Stephen… and set up false witnesses… They were enraged, and they ground their teeth against him. But he, full of the Holy Spirit, gazed into heaven and saw the glory of God, and Jesus standing at the right hand of God; and he said, ‘Behold, I see the heavens opened’… Then they cast him out of the city and stoned him… And he knelt down and cried with a loud voice, ‘Lord, do not hold this sin against them.’ ”—Acts 6:8-7:60.


1946 ◽  
Vol 11 (1) ◽  
pp. 2-2

In the article “Infant Speech Sounds and Intelligence” by Orvis C. Irwin and Han Piao Chen, in the December 1945 issue of the Journal, the paragraph which begins at the bottom of the left hand column on page 295 should have been placed immediately below the first paragraph at the top of the right hand column on page 296. To the authors we express our sincere apologies.


VASA ◽  
2010 ◽  
Vol 39 (4) ◽  
pp. 344-348 ◽  
Author(s):  
Jandus ◽  
Bianda ◽  
Alerci ◽  
Gallino ◽  
Marone

A 55-year-old woman was referred because of diffuse pruritic erythematous lesions and an ischemic process of the third finger of her right hand. She was known to have anaemia secondary to hypermenorrhea. She presented six months before admission with a cutaneous infiltration on the left cubital cavity after a paravenous leakage of intravenous iron substitution. She then reported a progressive pruritic erythematous swelling of her left arm and lower extremities and trunk. Skin biopsy of a lesion on the right leg revealed a fibrillar, small-vessel vasculitis containing many eosinophils.Two months later she reported Raynaud symptoms in both hands, with a persistent violaceous coloration of the skin and cold sensation of her third digit of the right hand. A round 1.5 cm well-delimited swelling on the medial site of the left elbow was noted. The third digit of her right hand was cold and of violet colour. Eosinophilia (19 % of total leucocytes) was present. Doppler-duplex arterial examination of the upper extremities showed an occlusion of the cubital artery down to the palmar arcade on the right arm. Selective angiography of the right subclavian and brachial arteries showed diffuse alteration of the blood flow in the cubital artery and hand, with fine collateral circulation in the carpal region. Neither secondary causes of hypereosinophilia nor a myeloproliferative process was found. Considering the skin biopsy results and having excluded other causes of eosinophilia, we assumed the diagnosis of an eosinophilic vasculitis. Treatment with tacrolimus and high dose steroids was started, the latter tapered within 12 months and then stopped, but a dramatic flare-up of the vasculitis with Raynaud phenomenon occurred. A new immunosupressive approach with steroids and methotrexate was then introduced. This case of aggressive eosinophilic vasculitis is difficult to classify into the usual forms of vasculitis and constitutes a therapeutic challenge given the resistance to current immunosuppressive regimens.


2014 ◽  
Vol 76 (1) ◽  
pp. 14-17
Author(s):  
Yoshiyuki KUWAE ◽  
Kunitaka HARUNA ◽  
Yasushi SUGA

2020 ◽  
pp. 40-50
Author(s):  
Boris Morgenroth ◽  
Thomas Stark ◽  
Julian Pelster ◽  
Harjeet Singh Bola

Optimization of process steam requirement in order to maximize sugar recovery and export power along with manpower optimization is a must for sugar factories to survive under difficult conditions and to earn additional revenues. The process steam demand of greenfield and revamped plants has been reduced to levels of 32–38% from originally more than 50% steam on cane in the case of the brownfield plants. In addition, significant improvement in the power requirement of the plants has been achieved. Bagasse drying offers a good potential to improve the power export. Different available concepts are compared with a focus on bagasse steam drying and low temperature bagasse drying. In order to set up an optimized highly efficient plant or to optimize an existing plant to achieve competitive benchmarks, good process design and the right equipment selection are very important. Experience has been gained with multiple stage or double effect crystallization in the beet sugar industry offering further steam optimization potential. Vapour recompression is also an option to substitute live steam by electrical power. This even provides options to reduce the steam demand from the power plant for the sugar process down to zero. Key aspects concerning the process design and equipment selection are described.


1970 ◽  
Vol 22 ◽  
Author(s):  
R. Goossens ◽  
J. De Schuyter

In  this article, we tried to perform the drawing of forest maps, together with  the calculations involved, automatically by means of relatively simple aids.      The computer unit used is an office computer Olivetti P203. As an example  the growing stock (in m3/ha) was mapped out. The proper inventory in the field is done  according to the classical method by means of a previously fixed network of  squares (70,7 m x 70,7 m), which corresponds to two plots a ha.     The quantity which is measured and mapped out (in this case the growing  stock) is in a similar form not very useful in mapping. Therefore a division  in classes (Ku) numbered from 0 to 9, is set up. An appropriate program  calculates for a certain number of points within this elementary square, to which  class they have to be assigned, whereas the typewriter prints the  corresponding code number on the right place.     Fig. 1 and the formulas (1), (2) and (3) represent the principle o[ the  calculations while fig. 2A and B reproduce the results printed by the  typewriter for a elementary square of respective 1” X 1” and 2” X 2”. The  whole of similar network of squares eventually results in a basical document,  on which the existing forest map with an adapted scale is laid (see appendix  3) and the class limits are drawn.     If desirable, the scale may be adapted when the forest map under discussion  is definitely reproduced.


Author(s):  
Richard McCleary ◽  
David McDowall ◽  
Bradley J. Bartos

Chapter 8 focuses on threats to construct validity arising from the left-hand side time series and the right-hand side intervention model. Construct validity is limited to questions of whether an observed effect can be generalized to alternative cause and effect measures. The “talking out” self-injurious behavior time series, shown in Chapter 5, are examples of primary data. Researchers often have no choice but to use secondary data that were collected by third parties for purposes unrelated to any hypothesis test. Even in those less-than-ideal instances, however, an optimal time series can be constructed by limiting the time frame and otherwise paying attention to regime changes. Threats to construct validity that arise from the right-hand side intervention model, such as fuzzy or unclear onset and responses, are controlled by paying close attention to the underlying theory. Even a minimal theory should specify the onset and duration of an impact.


Author(s):  
David K. Jones

The fight over an exchange had a very different dynamic in New Mexico because there were no loud voices on the right calling for the state to reject control. Republican Governor Susanna Martinez supported retaining control, but strongly preferred a governance model that allowed insurers to serve on the board of directors and limited the degree of oversight by the board on the types of plans that could be sold on the exchange. Governor Martinez vetoed legislation in 2011 that would have set up a different model of an exchange. Institutional quirks meant the legislature did not have the opportunity to weigh in again for two years, until 2013. By this point it was too late and the state had to rely on the federal website despite passing legislation to run its own exchange.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Velarie Ansu ◽  
Stephanie Dickinson ◽  
Alyce Fly

Abstract Objectives To determine which digit and hand have the highest and lowest skin carotenoid scores, to compare inter-and-intra-hand variability of digits, and to determine if results are consistent with another subject. Methods Two subjects’ first(F1), second(F2), third(F3) and fifth(F5) digits on both hands were measured for skin carotenoids with a Veggie Meter, for 3 times on each of 18 days over a 37-day period. Data were subjected to ANOVA in a factorial treatment design to determine main effects for hand (2 levels), digits (4), and days (18) along with interactions. Differences between digits were determined by Tukey's post hoc test. Results There were significant hand x digit, hand x day, digit x day, and hand x digit x day interactions and significant simple main effects for hand, digit, and day (all P < 0.001). Mean square errors were 143.67 and 195.62 for subject A and B, respectively, which were smaller than mean squares for all main effects and interactions. The mean scores ± SD for F1, F2, F3, and F5 digits for the right vs left hands for subject A were F1:357.13 ± 45.97 vs 363.74 ± 46.94, F2:403.17 ± 44.77 vs. 353.20 ± 44.13, F3:406.76 ± 43.10 vs. 357.11 ± 45.13, and F5:374.95 ± 53.00 vs. 377.90 ± 47.38. For subject B, the mean scores ± SD for digits for the right vs left hands were F1:294.72 ± 61.63 vs 280.71 ± 52.48, F2:285.85 ± 66.92 vs 252.67 ± 67.56, F3:268.56 ± 57.03 vs 283.22 ± 45.87, and F5:288.18 ± 34.46 vs 307.54 ± 40.04. The digits on the right hand of both subjects had higher carotenoid scores than those on the left hands, even though subjects had different dominant hands. Subject A had higher skin carotenoid scores on the F3 and F2 digits for the right hand and F5 on the left hand. Subject B had higher skin carotenoid scores on F5 (right) and F1 (left) digits. Conclusions The variability due to hand, digit, and day were all greater than that of the 3 replicates within the digit-day for both volunteers. This indicates that data were not completely random across the readings when remeasuring the same finger. Different fingers displayed higher carotenoid scores for each volunteer. There is a need to conduct a larger study with more subjects and a range of skin tones to determine whether the reliability of measurements among digits of both hands is similar across the population. Funding Sources Indiana University.


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