Filters








247,197 Hits in 5.1 sec

Dynamic Similarity for Fields with NULL Values [chapter]

Li Zhao, Sung Sam Yuan, Qi Xiao Yang, Sun Peng
2002 Lecture Notes in Computer Science  
In this paper, we solve this problem by proposing a simple yet efficient method, Dynamic Similarity, which dynamically adjusts the similarity for field with NULL value.  ...  Furthermore, the percentage of correct duplicate records obtained by Dynamic Similarity but not obtained by Record Similarity will increase if the number of fields with NULL values increases.  ...  In Record Similarity, similarity for NULL values is 0, while in Dynamic Similarity, similarity for NULL values is dynamically adjusted with its dependent fields and dependent weightages.  ... 
doi:10.1007/3-540-46145-0_16 fatcat:rl7jv2icrjaxlel2wphhpbvdhq

Current sheets at three-dimensional magnetic nulls: Effect of compressibility

D. I. Pontin, A. Bhattacharjee, K. Galsgaard
2007 Physics of Plasmas  
Thus our results for the 2D null, when compared with the solution of Ref. [16] , can be explained by similar reasoning. V.  ...  The evolution of the null point for an ideal monatomic gas (γ = 5/3) is very similar to the case where the spine is driven.  ... 
doi:10.1063/1.2734949 fatcat:rmvvarz7tjdfljp7xe63jg2r5e

Current accumulation at an asymmetric 3D null point caused by generic shearing motions

K. Galsgaard, D. I. Pontin
2011 Astronomy and Astrophysics  
The magnetic field is frozen to the boundaries and the boundary velocity is only non-zero where the imposed driving is for stressing the system is applied. Results.  ...  We investigate the dynamical evolution of the reconnection process at an initially linear 3D null point that is stressed by a localised shear motion across the spine axis.  ...  Here this integral in general reaches its maximum value for a field line in the fan plane.  ... 
doi:10.1051/0004-6361/201117532 fatcat:eej5p7xb2bec7nneypys3yyflu

Simulated evolution of three-dimensional magnetic nulls leading to generation of cylindrically-shaped current sheets

Sanjay Kumar, R. Bhattacharyya
2017 Physics of Plasmas  
The initial field supports 3D magnetic nulls having classical spine axis and dome-shaped fan surface; and exerts non-zero Lorentz force on the magnetofluid.  ...  The morphology of the current sheets is similar to a cylindrical surface where the surface encloses the spine axis.  ...  The initial magnetic field B needs to be prescribed such as to have inherent 3D nulls along with non-zero Lorentz force, required for dynamical evolution.  ... 
doi:10.1063/1.4985682 fatcat:j65hz6o5a5a2jm7kteyuh572cq

Feedback Gains modulate with Motor Memory Uncertainty [article]

Sae Franklin, David W. Franklin
2021 arXiv   pre-print
After adaptation had plateaued,there was a change in the co-contraction and visuomotor feedback gains relative to null field movements, but no differences (apart from the final muscle activation pattern  ...  ) between the abrupt and gradual introduction of dynamics.  ...  A value of 100% indicates perfect compensation for the force field. Force compensation in the null field was quantified with respect to the full force field value, so a value of 0 is expected.  ... 
arXiv:2008.07574v2 fatcat:5imyec32arfqpctoqndjaihvrm

Feedback Gains modulate with Motor Memory Uncertainty

Sae Franklin, David W. Franklin
2021 Neurons, Behavior, Data analysis, and Theory  
After adaptation had plateaued,there was a change in the co-contraction and visuomotor feedback gains relative to null field movements, but no differences (apart from the final muscle ac-  ...  Participants grasped a robotic manipulandum and reached while a curl force field was introduced gradually or abruptly.  ...  ACKNOWLEDGEMENTS We thank Daniel Wolpert and James Ingram for support with the experimental facilities.  ... 
doi:10.51628/001c.22336 fatcat:nitz2e4whzbiznpqty2pwfuptu

Older adults learn less, but still reduce metabolic cost, during motor adaptation

Helen J. Huang, Alaa A. Ahmed
2014 Journal of Neurophysiology  
A force field was used to add novel dynamics. Older adults had greater movement deviations and compensated for just 65% of the novel dynamics compared with 84% in young adults.  ...  The ability to learn new movements and dynamics is important for maintaining independence with advancing age.  ...  Renee Dudley for help with data collections and to members of the Neuromechanics Lab and Locomotion Lab for discussion about the project. GRANTS  ... 
doi:10.1152/jn.00401.2013 pmid:24133222 pmcid:PMC3921372 fatcat:gnhreuqsjnevpnouxsnhkkp4ru

Implementing a Language with Flow-Sensitive and Structural Typing on the JVM

David J. Pearce, James Noble
2011 Electronical Notes in Theoretical Computer Science  
Dynamically typed languages are flexible and impose few burdens on the programmer. In contrast, static typing leads to software that is more efficient and has fewer errors.  ...  The Whiley language aims to hit a sweet spot between dynamic and static typing. This is achieved through structural subtyping and by typing variables in a flow-sensitive fashion.  ...  A simple approach (used in many dynamic languages), is to translate them as HashMaps which map field names to values.  ... 
doi:10.1016/j.entcs.2011.11.005 fatcat:ld27j6corranxmcqg4k35na4xq

Prolegomena to any future Quantum Gravity [article]

John Stachel
2006 arXiv   pre-print
to the field equations of general relativity.  ...  I shall discuss some "conditions of possibility" of a quantum theory of gravity, stressing the need for solutions to some of fundamental problems confronting any attempt to apply some method of quantization  ...  Mihaela Iftime for reading an earlier draft of this paper and making several suggestions for improvement of this version.  ... 
arXiv:gr-qc/0609108v1 fatcat:ppmiwlyunfatzmcfehszlycfgy

Dynamics and waves near multiple magnetic null points in reconnection diffusion region

X. H. Deng, M. Zhou, S. Y. Li, W. Baumjohann, M. Andre, N. Cornilleau, O. Santolík, D. I. Pontin, H. Reme, E. Lucek, A. N. Fazakerley, P. Decreau (+15 others)
2009 Journal of Geophysical Research  
It is found that the angle between the fans of the nulls is quite close to the theoretically estimated maximum value of the group-velocity cone angle for the whistler wave regime of reconnection.  ...  H., et al. (2009), Dynamics and waves near multiple magnetic null points in reconnection diffusion region,  ...  We thank all members of the Cluster team for the high-quality data and successful operation. X.H. Deng thanks J.F. Drake, A. Bhattacharjee, and Maha Ashour-Abdalla for their helpful discussion.  ... 
doi:10.1029/2008ja013197 fatcat:qbvp3xmsvvb57loud4axsz6xj4

Free evolution of nonlinear scalar field collapse in double-null coordinates [article]

Lior M. Burko
1997 arXiv   pre-print
The corresponding power indices agree with the integer values predicted by linearized theory.  ...  Our numerical code is based on double-null coordinates and on free evolution of the metric functions and the scalar field. The numerical code is stable and second-order accurate.  ...  Acknowledgments I am indebted to Amos Ori for many stimulating and helpful discussions.  ... 
arXiv:gr-qc/9710043v1 fatcat:gakyw44vozhmfezphklpeksazy

Kinematics of discretely self-similar spherically symmetric spacetimes

Carsten Gundlach, José M. Martín-García
2003 Physical Review D, Particles and fields  
Each building block contains one radial null geodesic that is invariant under the self-similarity (self-similarity horizon).  ...  We summarize the consequences of the twin assumptions of (discrete) self-similarity and spherical symmetry for the global structure of a spacetime.  ...  Acknowledgments We would like to thank James Vickers and Bernard Carr for helpful discussions. This research was supported by EPSRC grant GR/N10172/01.  ... 
doi:10.1103/physrevd.68.064019 fatcat:4idhkyrjyrf23ehlhsz3lkvcae

Tensionless string in the notoph background

K Ilienko, A A Zheltukhin
1999 Classical and quantum gravity  
Identification of this degree of freedom with the notoph field ϕ of Ogievetskii-Polubarinov-Kalb-Ramond is suggested.  ...  Application of a two-component spinor formalism allows us a reduction of the complete system of non-linear partial differential equations and constraints governing the interacting null string dynamics  ...  This implies that for the purposes of interaction with a null string the behaviour of antisymmetric gauge field B ab is classically equivalent to that of the real-valued scalar field.  ... 
doi:10.1088/0264-9381/16/2/005 fatcat:dg6dd34m6vhlvaktbxan5rrdqu

Interior dynamics of neutral and charged black holes

Jun-Qi Guo, Pankaj S. Joshi
2015 Physical Review D  
In simulating scalar collapses in Schwarzschild and Reissner-Nordstrom geometries, Kruskal and Kruskal-like coordinates are used, respectively, with the presence of a scalar field being taken into account  ...  This is in accord with the Belinskii, Khalatnikov, and Lifshitz conjecture.  ...  Gálvez Ghersi, and Ken-ichi Nakao for useful discussions. JQG would like to thank Simon Fraser University where part of this work was done.  ... 
doi:10.1103/physrevd.92.064013 fatcat:trnbbtv7ujcx5itaoixfxcpyhe

Post-Stroke Adaptation of Lateral Foot Placement Coordination in Variable Environments

Andrew C Dragunas, Tara Cornwell, Roberto Lopez-Rosado, Keith E. Gordon
2021 IEEE transactions on neural systems and rehabilitation engineering  
Individuals with stroke often have difficulty modulating their lateral foot placement during gait, a primary strategy for maintaining lateral stability.  ...  We also found that compared to individuals without stroke in the Null Field, individuals with stroke had weaker COM-FP correlations (Paretic < Control: p = 0.001, Non-Paretic < Control: p = 0.007) and  ...  ACKNOWLEDGMENT The authors would like to thank the members of the Human Agility Laboratory for their helpful comments and suggestions in preparation of this manuscript.  ... 
doi:10.1109/tnsre.2021.3072252 pmid:33835919 pmcid:PMC8115208 fatcat:ctu4gkoysjhd7kjj5i24mdv3ie
« Previous Showing results 1 — 15 out of 247,197 results