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Edge, Ridge, and Blob Detection with Symmetric Molecules [article]

Rafael Reisenhofer, Emily J. King
2019 arXiv   pre-print
We present a novel approach to the detection and characterization of edges, ridges, and blobs in two-dimensional images which exploits the symmetry properties of directionally sensitive analyzing functions  ...  To further demonstrate the applicability, we show how the proposed ridge measure can be used to detect and characterize blood vessels in digital retinal images and how the proposed blob measure can be  ...  Starck for suggesting that we extend the framework to the case of blob detection and M. Schäfer for insightful discussions on the subject of α-molecules. We are grateful to Q.  ... 
arXiv:1901.09723v2 fatcat:tzp6gg2vgrbndhzzejwjtdxgxi

An automated fracture trace detection technique using the complex shearlet transform

Rahul Prabhakaran, Pierre-Olivier Bruna, Giovanni Bertotti, David Smeulders
2019 Solid Earth Discussions  
The method consists of ridge detection using the complex shearlet transform coupled with post-processing algorithms that threshold, skeletonize, and vectorize fracture traces.  ...  In this paper, an automated fracture trace detection technique is introduced.  ...  of the even symmetric and odd symmetric shearlets can be used to detect edges and ridges.  ... 
doi:10.5194/se-2019-104 fatcat:e2ofbxkm3jhstglrxkmc7rhaum

An automated fracture trace detection technique using the complex shearlet transform

Rahul Prabhakaran, Pierre-Olivier Bruna, Giovanni Bertotti, David Smeulders
2019 Solid Earth  
The method consists of ridge detection using the complex shearlet transform coupled with post-processing algorithms that threshold, skeletonize, and vectorize fracture traces.  ...  In this paper, an automated fracture trace detection technique is introduced.  ...  A5 Edge and ridge detection using the complex shearlet transform The behaviour of the coefficients of the even-symmetric and odd-symmetric shearlets can be used to detect edges and ridges.  ... 
doi:10.5194/se-10-2137-2019 fatcat:ppw4wmrn2na5rmdusa5pgwj554

3-D shape estimation of DNA molecules from stereo cryo-electron micro-graphs using a projection-steerable snake

M. Jacob, T. Blu, C. Vaillant, J.H. Maddocks, M. Unser
2006 IEEE Transactions on Image Processing  
We estimate the shape by matching the projections of a 3-D global shape model with the micrographs; we choose the global model as a 3-D filament with a B-spline skeleton and a specified radial profile.  ...  The active contour algorithm iteratively updates the B-spline coefficients, which requires us to evaluate the projections and match them with the micrographs at every iteration.  ...  El-Bez, and E. Larquet of the LAU, UNIL, for the active discussions and the data.  ... 
doi:10.1109/tip.2005.860310 pmid:16435551 fatcat:kzcplg3wzzctnea7cb7j37lnfe

Magnetic interaction of jets and molecular clouds in NGC 4258

M. Krause, C. Fendt, N. Neininger
2007 Astronomy and Astrophysics  
NGC 4258 is a well known spiral galaxy with a peculiar large scale jet flow detected in the radio and in H-alpha.  ...  We detected two parallel CO ridges along a position angle of -25 degr with a total length of about 80 arcsec (2.8 kpc), separated by a CO-depleted funnel with a width of about 5 arcsec (175 pc).  ...  We acknowledge discussions with Dennis Downes and Heino Falcke. We like to thank Phil Kronberg for fruitful discussions and helpful comments on the manuscript.  ... 
doi:10.1051/0004-6361:20066445 fatcat:k5otj6amwjazji3txubmat6r74

Recognition of immunogold markers in electron micrographs

Ruixuan Wang, Himanshu Pokhariya, Stephen J. McKenna, John Lucocq
2011 Journal of Structural Biology  
paper automatically detects and counts immunogold markers, estimating 26 the location, size and type of each marker.  ...  Colloidal gold particles (immunogold markers) are 22 commonly used to localise molecules of interest on ultrathin sections and can be visualised in transmis-23 sion electron micrographs as dark spots.  ...  Eliminating edges and ridges 157 The candidate gold markers detected so far are likely to include 158 false positive detections due to strong DoG responses to highly 159 contrasted edge-like and ridge-like  ... 
doi:10.1016/j.jsb.2011.07.005 pmid:21798353 fatcat:wdfjg5bc6ffezm4nrucxwle3fa

Macromolecules, Very Small Grains, and Large Dust Particles in the Whirlpool Galaxy M51 and Its Companion: A Unified View

David L. Block, Bruce G. Elmegreen, Alan Stockton, Marc Sauvage
1997 Astrophysical Journal  
The dust lanes in the arms show sharp inner edges from shock fronts, dense, regularly spaced clumps with star formation, and feathered outer edges from disruption by star formation.  ...  The diffuse gas in M51 is particularly striking: shell-like structures are common, the interarm clouds have spiral shapes, and the inner spiral dust lanes are remarkably symmetric.  ...  ISO is an ESA project with instruments funded by ESA member states (especially the PI countries: France, Germany, the Netherlands, and the United Kingdom) and with participation of ISAS and NASA.  ... 
doi:10.1086/310855 fatcat:jnzjmpf4yfa4ndjbuzx3bi4ov4

Image analysis in fluorescence microscopy: Bacterial dynamics as a case study

Sven van Teeffelen, Joshua W. Shaevitz, Zemer Gitai
2012 Bioessays  
These images contain a vast amount of information, but this information is often hidden behind various sources of noise, convoluted with other information, and stochastic in nature.  ...  Technical advances in both molecular biology and microscopy have made it possible to image cells from many genetic and environmental backgrounds.  ...  A: Image preparation and the sequence of morphological operations with inversion, thresholding, edge and detection algorithms are shown.  ... 
doi:10.1002/bies.201100148 pmid:22415868 pmcid:PMC4056673 fatcat:oin43oh7zzgclkjcngkvaicyam

Kinematics of the anemic cluster galaxy NGC 4548 - Is stripping still active ? [article]

B. Vollmer , W.J. Duschl Institut fuer Theoretische Astrophysik, Heidelberg, Germany - Observatoire de Paris, Meudon, France - Laboratoire d'Astronomie Spatiale, Marseille, France)
1999 arXiv   pre-print
The overall rotation curve is derived with a tilted ring model. We compare our rotation curve with previous ones and discuss the differences.  ...  We present new HI (20" resolution) and CO observations of NGC 4548, an anemic galaxy in the Virgo cluster. The atomic gas distribution shows a ring structure which is distorted at the northern edge.  ...  Roy and P. Martin for making their Hα data available. We thank V. Rubin for making available her data prior to publication, J. Braine for fruitful discussions, and the referee for useful advices.  ... 
arXiv:astro-ph/9907351v1 fatcat:ajkfwm3xefbphhvq5nbix44cgq

Kinematics of the Envelope and Two Bipolar Jets in the Class 0 Protostellar System L1157 [article]

Woojin Kwon, Ian W. Stephens KASI,
2015 arXiv   pre-print
All the CO isotopes and CS, CN, and N_2H^+ have been detected and imaged.  ...  We marginally detected the features that can be interpreted as a rotating inner envelope in C^17O and C^18O and as an infalling outer envelope in N_2H^+.  ...  McDonnell Foundation, the Gordon and Betty Moore Foundation, the Kenneth T. and Eileen L.  ... 
arXiv:1510.02155v1 fatcat:yqk2om4berfevmulnvfqol24ji

Spitzer Observations of Interstellar Object 1I/'Oumuamua

David E. Trilling, Michael Mommert, Joseph L. Hora, Davide Farnocchia, Paul Chodas, Jon Giorgini, Howard A. Smith, Sean Carey, Carey M. Lisse, Michael Werner, Andrew McNeill, Steven R. Chesley (+11 others)
2018 Astronomical Journal  
We did not detect the object and place an upper limit on the flux of 0.3 uJy (3sigma).  ...  This model is consistent with the expected eta value and implied high albedo value for this solution, but, given our strict limits on CO and CO2, requires another gas species --- probably H2O --- to explain  ...  We thank the SSC Director for approving these DDT observations and the SSC staff for rapidly implementing these observations with their usual technical excellence.  ... 
doi:10.3847/1538-3881/aae88f fatcat:6fgodx7g6vfhdihfbxoi2c7fnu

Linear Scale-Space I: Basic Theory [chapter]

Tony Lindeberg, Bart M. ter Haar Romeny
1994 Computational Imaging and Vision  
This representation has been used for feature detection and data compression. Among features that can be detected are blobs (maxima), peaks and ridges etc (Crowley et al. , 1987 . Properties.  ...  detection, 54 edge detection, 50 in feature detection, 49 non-creation of, 14, 17{19 of Laplacian, 15, 17 localization error, 54 ordering across scales, 12 ridge detection, 52 .  ... 
doi:10.1007/978-94-017-1699-4_1 dblp:series/civ/LindebergR94 fatcat:h4pzwzujtvh7jfpummeocn5fri

Scale-space theory: a basic tool for analyzing structures at different scales

Tony Lindeberg
1994 Journal of Applied Statistics  
The output from the scale-space representation can be used for a variety o f early visual tasks operations like feature detection, feature classi cation and shape computation can be expressed directly  ...  The conditions that specify the Gaussian kernel are, basically, linearity and shift-invariance combined with di erent w ays of formalizing the notion that structures at coarse scales should correspond  ...  Chapel Hill, Stephen Pizer, with all of whom I have had several highly interesting discussions.  ... 
doi:10.1080/757582976 fatcat:a5fsm3nfwnhbtbu6omm7gbhz64

Dynamical effects in fluid complex plasmas

Mierk Schwabe, Gregor Morfill, Hubertus Thomas
2009 Zenodo  
Fluxes of plasma particles onto the grain surface charge it, and the microparticles interact with each other.  ...  ., with a laser, recording the scattered light allows to perform fully resolved kinetic studies at all relevant frequencies, e.g., the Einstein frequency, Debye frequency, and plasma frequency.  ...  The plasma chamber was filled with Neon gas at a pressure of 16 Pa with a small symmetrical gas flux.  ... 
doi:10.5281/zenodo.3927599 fatcat:74mamb3ebncsppmshqnhaemhnq

The complex multi-scale structure in simulated and observed emission maps of the proto-cluster cloud G0.253+0.016 (`the Brick') [article]

Maya A. Petkova, J. M. Diederik Kruijssen, A. Louise Kluge, Simon C. O. Glover, Daniel L. Walker, Steven N. Longmore, Jonathan D. Henshaw, Stefan Reissl, James E. Dale
2021 arXiv   pre-print
To facilitate the comparison, we post-process the simulation and create synthetic ALMA maps of molecular line emission from eight molecules.  ...  High-resolution observations with the Atacama Large Millimeter/submillimeter Array (ALMA) have revealed its complex, hierarchical structure.  ...  ACKNOWLEDGEMENTS MAP would like to thank her colleagues from the MUSTANG group for many discussions and assistance throughout this project. MAP and JMDK gratefully acknowledge funding from the Eu-  ... 
arXiv:2104.09558v1 fatcat:evgxudw4v5cqfn3z3c4k6i25ym
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