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Midcourse Space Experiment Precision Ephemeris

Richard I. Abbot, E. Michael Gaposchkin, Curt von Braun
2000 Journal of Guidance Control and Dynamics  
A collection of frames, or frameset, typically consists of between 8 and 16 frames.  ...  To assess the metric performance of the sensor, routine on-orbit metric calibration is performed. In addition, a complete independent error assessment was made using actual flight data.  ... 
doi:10.2514/2.4510 fatcat:jgs4qywd6feb5b2fdmpro3htdu

Comparative Evaluation of Background Subtraction Algorithms in Remote Scene Videos Captured by MWIR Sensors

Guangle Yao, Tao Lei, Jiandan Zhong, Ping Jiang, Wenwu Jia
2017 Sensors  
Each video sequence in this dataset is identified with specific BS challenges and the pixel-wise ground truth of foreground (FG) for each frame is also provided.  ...  Proper evaluation metrics or criteria were employed to evaluate the capability of each BS algorithm to handle different kinds of BS challenges represented in this dataset.  ...  Jiandan Zhong annotated each frame of IR video sequence. Ping Jiang hosted the project of object tracking in IR video sequence and conceived the idea of this paper.  ... 
doi:10.3390/s17091945 pmid:28837112 pmcid:PMC5621003 fatcat:odygwwfz45awdflfy26qjasg3y

IRACproc: a software suite for processing and analyzing Spitzer /IRAC data

Michael T. Schuster, Massimo Marengo, Brian M. Patten, David R. Silva, Rodger E. Doxsey
2006 Observatory Operations: Strategies, Processes, and Systems  
By protecting sources with a metric that accounts for these large variations in the PSFs, our technique maintains the structure and photometric reliability of the PSF, while at the same time removing transients  ...  The under/critically sampled IRAC PSFs are subject to large variations in shape between successive frames as a result of sub-pixel shifts from dithering or telescope jitter.  ...  Our method for outlier rejection is a form of sigma-clipping, with the mean or median replaced with the best estimate and the "sigma" replaced with the metric.  ... 
doi:10.1117/12.673134 fatcat:fp57cwr72jcvxpf7xbz3xmr2s4

Lifts of connections to the bundle of (1,1) type tensor frames

Habil FATTAYEV
2021 Sigma Journal of Engineering and Natural Sciences  
Also we study the properties of the geodesic lines corresponding to the complete lift of the linear connection and investigate the relations between Sasaki metric and lifted connections on the bundle of  ...  In this paper we consider the bundle of (1,1) type tensor frames over a smooth manifold, define the horizontal and complete lifts of symmetric linear connection into this bundle.  ...  The relations between various metrics and connections on the C T M ( ) have been studied by Mok [8] .  ... 
doi:10.14744/sigma.2021.00007 fatcat:4njeaizxybd2pl4umwgalsgpyy

Gravity, torsion, Dirac field and computer algebra using MAPLE and REDUCE [article]

D.N. Vulcanov (Max-Planck-Institut fur Gravitationsphysik, Albert-Einstein-Institut, Golm, Germany)
2002 arXiv   pre-print
The main part of the procedures is devoted to the construction of Pauli and Dirac matrices algebra on an anholonomic orthonormal reference frame.  ...  The article presents computer algebra procedures and routines applied to the study of the Dirac field on curved spacetimes.  ...  Alcubierre and many others, for help, support and fruitful discussions. Special thanks go to A. Popova, for carefully and critically reading of the article.  ... 
arXiv:gr-qc/0209096v2 fatcat:okmsm3qx4vanrmd7kf6mbnnh3i

Page 5640 of Mathematical Reviews Vol. , Issue 2000h [page]

2000 Mathematical Reviews  
(CH-BERN; Bern); Romaguera, Salvador (E-VLNP-AM; Valencia) Quasi-metric spaces, quasi-metric hyperspaces and uniform local compactness.  ...  Summary: “We show that every locally compact quasi-metrizable Moore space admits a uniformly locally compact quasi-metric. We also observe that every equinormal quasi-metric is cofinally complete.  ... 

On UV-completion of Palatini-Higgs inflation [article]

Yusuke Mikura, Yuichiro Tada
2021 arXiv   pre-print
We investigate the UV-completion of the Higgs inflation in the metric and the Palatini formalisms.  ...  The new field introduced in this way successfully flattens the field-space and UV-completes the Higgs inflation in the metric formalism.  ...  Acknowledgments We are grateful to Kyohei Mukaida and Shuichiro Yokoyama for helpful discussions. Y.T. is supported by JSPS KAKENHI Grants No. JP19K14707 and No. JP21K13918.  ... 
arXiv:2110.03925v1 fatcat:srtaer2gknhrdk4mstzbm2z5je

Nonperturbative solutions of string theory in gravitational backgrounds

Octávio A. Mattos, Victor O. Rivelles
1993 Physical Review Letters  
We show that either left-movers or right-movers are the only background independent non-perturbative solutions of the field equations for an arbitrary static metric.  ...  They are stable and have a conserved topological charge being therefore topological solitons.  ...  In fact, the class of metrics (7) corresponds to a comoving frame for the string.  ... 
doi:10.1103/physrevlett.70.1583 pmid:10053332 fatcat:aaypg4nlzvfgjpgqibkiuun3sm

Twistor Spaces for QKT Manifolds

P. S. Howe, A. Opfermann, G. Papadopoulos
1998 Communications in Mathematical Physics  
We give four examples of geodesically complete QKT manifolds one of which is a generalisation of the LeBrun geometry.  ...  We then construct the twistor space associated with a QKT manifold and show that under certain conditions it is a K\"ahler manifold with a complex contact structure.  ...  This QKT metric is geodesically complete if we choose λ 2 > |λ 1 |.  ... 
doi:10.1007/s002200050469 fatcat:fuqli3zjlfhuvcftedfscin7gq

Non-commutativity from the double sigma model

Dimitri Polyakov, Peng Wang, Houwen Wu, Haitang Yang
2015 Journal of High Energy Physics  
The physical interpretations of the metric and other parameters in the double sigma model are completely dictated by the boundary conditions.  ...  As a bonus, the propagators of general frames in double sigma model for open string are also presented.  ...  and source are credited.  ... 
doi:10.1007/jhep03(2015)011 fatcat:na3n22ygq5f4rd4ohiobv4m5wu

Causality and the Skyrme model

G.W. Gibbons
2003 Physics Letters B  
The Born-Infeld-Skyrme model also satisfies both the dominant and strong energy conditions.  ...  I would like to thank him and Nick Manton for many helpful and enjoyable discussions.  ...  hence by the convexity property, so does the complete energy-momentum tensor T µν = T sigma µν + T Skyrme µν .  ... 
doi:10.1016/s0370-2693(03)00384-8 fatcat:zea5usjlxbaw3hshbqtwnkotym

Braneworld gravity in a symmetric space bulk

Nejat T Yilmaz
2010 Classical and quantum gravity  
By considering the p-brane motion in G/K symmetric space bulk we identify the G-invariant bulk metric in the solvable lie algebra gauge of the brane action.  ...  After calculating the Levi-Civita connection of this bulk metric we use it in the Gauss equation to compute the braneworld curvature in terms of the bulk coordinates.  ...  With this observation finally we can express the complete dynamics of the brane whose motion in a symmetric space bulk is governed by a symmetric space sigma model and which is coupled to the gravity and  ... 
doi:10.1088/0264-9381/27/14/145019 fatcat:4ag5cnufdvartiwq7gc7ut3eve

Supergravity Induced Interactions on Thick Branes [article]

Nejat Tevfik Yilmaz
2014 arXiv   pre-print
The gravity coupling of the symmetric space sigma model is studied in the solvable Lie algebra parametrization.  ...  The Einstein and scalar field equations are derived for flat brane geometry in the context of minimal and non-minimal gravity-bulk scalar couplings.  ...  sigma model action and which will also indirectly determine the metric g.  ... 
arXiv:1403.6017v1 fatcat:qrrdzmoa6fdaxdbkyk3a23ujam

Supergravity-induced interactions on thick branes

Nejat T. Yılmaz
2014 Chinese Physics B  
The gravity coupling of the symmetric space sigma model is studied in the solvable Lie algebra parametrization.  ...  The Einstein and scalar field equations are derived for flat brane geometry in the context of minimal and non-minimal gravity-bulk scalar couplings.  ...  sigma model action and which will also indirectly determine the metric g.  ... 
doi:10.1088/1674-1056/23/4/040401 fatcat:fedh7nueyrbg3nbyrkusdja6bi

On the use of algebraic programming in the general relativity [article]

D.N. Vulcanov (The West University of Timisoara, Theoretical and Computational Physics Dept., Timisoara, Romania)
2002 arXiv   pre-print
pd(sigma(3),sigma(2))=2*I*gen(0,2),pd(sigma(3), sigma(3))=2*I*gen(0,3),'x'); > grdisplay(dirac); where, of course, as in REDUCE version, the operators gen and gama does not represent a complete algebra  ...  dropped the complete list of the properties of the special products pr and &p, being very long.  ... 
arXiv:gr-qc/0010085v2 fatcat:xfycg74e4rb37azemawo6vr7d4
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