Three‐dimensional localization of blue whales using matched‐field processing techniques: Unusual behavior, unanswered questions

2000 ◽  
Vol 108 (5) ◽  
pp. 2613-2613
Author(s):  
A. M. Thode ◽  
G. L D’Spain ◽  
W. A. Kuperman
Author(s):  
B.V.V. Prasad ◽  
E. Marietta ◽  
J.W. Burns ◽  
M.K. Estes ◽  
W. Chiu

Rotaviruses are spherical, double-shelled particles. They have been identified as a major cause of infantile gastroenteritis worldwide. In our earlier studies we determined the three-dimensional structures of double-and single-shelled simian rotavirus embedded in vitreous ice using electron cryomicroscopy and image processing techniques to a resolution of 40Å. A distinctive feature of the rotavirus structure is the presence of 132 large channels spanning across both the shells at all 5- and 6-coordinated positions of a T=13ℓ icosahedral lattice. The outer shell has 60 spikes emanating from its relatively smooth surface. The inner shell, in contrast, exhibits a bristly surface made of 260 morphological units at all local and strict 3-fold axes (Fig.l).The outer shell of rotavirus is made up of two proteins, VP4 and VP7. VP7, a glycoprotein and a neutralization antigen, is the major component. VP4 has been implicated in several important functions such as cell penetration, hemagglutination, neutralization and virulence. From our earlier studies we had proposed that the spikes correspond to VP4 and the rest of the surface is composed of VP7. Our recent structural studies, using the same techniques, with monoclonal antibodies specific to VP4 have established that surface spikes are made up of VP4.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuta Saito ◽  
Shogo Hatayama ◽  
Yi Shuang ◽  
Paul Fons ◽  
Alexander V. Kolobov ◽  
...  

AbstractTwo-dimensional (2D) van der Waals (vdW) materials possess a crystal structure in which a covalently-bonded few atomic-layer motif forms a single unit with individual motifs being weakly bound to each other by vdW forces. Cr2Ge2Te6 is known as a 2D vdW ferromagnetic insulator as well as a potential phase change material for non-volatile memory applications. Here, we provide evidence for a dimensional transformation in the chemical bonding from a randomly bonded three-dimensional (3D) disordered amorphous phase to a 2D bonded vdW crystalline phase. A counterintuitive metastable “quasi-layered” state during crystallization that exhibits both “long-range order and short-range disorder” with respect to atomic alignment clearly distinguishes the system from conventional materials. This unusual behavior is thought to originate from the 2D nature of the crystalline phase. These observations provide insight into the crystallization mechanism of layered materials in general, and consequently, will be useful for the realization of 2D vdW material-based functional nanoelectronic device applications.


2018 ◽  
Vol 2018 ◽  
pp. 1-5
Author(s):  
Jamyson Oliveira Santos ◽  
Brunna da Silva Firmino ◽  
Matheus Santos Carvalho ◽  
Jean de Pinho Mendes ◽  
Lucas Novaes Teixeira ◽  
...  

Imaging examinations play an important role in the diagnosis of sialolithiasis, whose symptoms are initially confounded with other diseases. The objective of the present case report is to highlight imaging and processing techniques as well as image analysis for the preoperative assessment and planning of surgical interventions and adequate treatment of massive sialoliths. A 35-year-old male patient presented complaining of pain in the submandibular region and purulent secretions from a lingual caruncle with slightly increased volume in the region. Imaging examinations were ordered as follows: cone beam computed tomography, ultrasonography, and three-dimensional reconstruction, including clinical evaluation. A final diagnosis of sialolithiasis was established. Surgery was indicated and carried out by using a lateral transcervical approach for complete resection of the gland, which was based on the calculation of the total volume of the sialolith, thus increasing the surgery’s success.


2011 ◽  
pp. 130-174
Author(s):  
Burak Ozer ◽  
Tiehan Lv ◽  
Wayne Wolf

This chapter focuses on real-time processing techniques for the reconstruction of visual information from multiple views and its analysis for human detection and gesture and activity recognition. It presents a review of the main components of three-dimensional visual processing techniques and visual analysis of multiple cameras, i.e., projection of three-dimensional models onto two-dimensional images and three-dimensional visual reconstruction from multiple images. It discusses real-time aspects of these techniques and shows how these aspects affect the software and hardware architectures. Furthermore, the authors present their multiple-camera system to investigate the relationship between the activity recognition algorithms and the architectures required to perform these tasks in real time. The chapter describes the proposed activity recognition method that consists of a distributed algorithm and a data fusion scheme for two and three-dimensional visual analysis, respectively. The authors analyze the available data independencies for this algorithm and discuss the potential architectures to exploit the parallelism resulting from these independencies.


Author(s):  
Jason B. Carneal ◽  
Paisan Atsavapranee ◽  
Carl W. Baumann ◽  
John H. Hamilton ◽  
Jerry Shan

A Global Laser Range Profilometry (GLRP) System has been developed at the Naval Surface Warfare Center, Carderock Division (NSWCCD) for the measurement of three dimensional wave surfaces. A laser diode array consisting of 100 diodes operating at 650nm with an energy output of 3.5 mW was used to illuminate the wave surface seeded with fluorescent dye at various points in the Miniature Water Basin (MWB) facility at NSWCCD. A CCD camera located above the water surface recorded successive images of the laser array at 30 frames per second. Image processing techniques were used to locate the centroid of the laser array diode locations in the collected images. Calibration images were taken at various calm water heights in order to convert the image centroid locations to real coordinates. Two- and three-dimensional results are presented, along with error analysis of the GLRP system and comparison to flow visualization. A discussion of possible applications and planned future work is also presented in this work.


2016 ◽  
Vol 88 (6) ◽  
pp. 621-629 ◽  
Author(s):  
Lei Wang ◽  
Bugao Xu ◽  
Weidong Gao

Most photoelectric and imaging methods for yarn hairiness measurements often provide underestimated data of hairy fibers measured from light projection, which ignores the spatial orientations and shapes of protruding fibers. In this project, a three-dimensional (3D) system was developed to detect hairy fibers from multiple perspectives and to reconstruct a 3D model for the yarn that permits fibers to be traced spatially. The system utilized two angled planar mirrors to view a yarn from five different perspectives simultaneously, and a digital camera to capture the multiple images in one panoramic picture. The image-processing techniques were used to dissect the panoramic picture into five sub-images containing separate views of the yarn, and to segment the sub-images to obtain yarn silhouettes showing the edges of the yarn and hairy fibers. A 3D model of the yarn could be built by merging the five silhouettes with the angles defined by the scene geometry of the dual mirrors. From the 3D model, hairy fibers protruding from the yarn core could be traced in the space for accurate length measurements. The system represents a simple and practical solution for the 3D measurement of yarn hairiness.


2002 ◽  
Vol 739 ◽  
Author(s):  
Meg Abraham ◽  
Peter Fuqua ◽  
David P. Taylor ◽  
William W. Hansen ◽  
Henry Helvajian ◽  
...  

ABSTRACTThe use of lasers to create intricate three-dimensional and buried structures [1] in photostructural glass has been well demonstrated at The Aerospace Corporation over the past four years. In these instances the glass used (Foturan™, made by the Schott Group) forms a silver nucleation sites on exposure to intense UV laser light via a two-photon process. Subsequent annealing causes a localized crystal growth to form a meta-silicate phase which can be etched in dilute hydrofluoric acid at rates of 20 to 50 times that of the unprocessed glass. We are now in the process of experimenting with another formulation of photosensitive glass, also pioneered by Corning Glass Works, that behaves differently during the bake process. In the second case, a photoexposure and bake process creates a silver-halide crystal and forms an adjacent void in the glass. A second photoexposure and bake allows for the migration of more silver into the void creating patterned formations of silver nano-wires [2]. Recent experiments with this type of glass have shown that the manipulation of the size and density of the embedded nano-wires as well as the overall pattern of the clusters can be controlled using direct-write exposure to laser processing.


1994 ◽  
Vol 02 (03) ◽  
pp. 161-185 ◽  
Author(s):  
MICHAEL B. PORTER ◽  
A. TOLSTOY

In matched field processing sophisticated acoustic models are combined with signal processing techniques to localize an acoustic source in the ocean. A key challenge has been to develop schemes that work not just in idealized simulations but in realistic scenarios. Additionally it has been difficult to get a sense of the relative merits of different schemes: there has been no common set of problems to test the techniques. To assess the state of the art, a workshop was held in May 1993 at the Naval Research Laboratory where both simulated and experimental data were provided to the community of users to test the algorithms. However, researchers were not given the true source location and thus exercised their algorithms blindly. We describe here the test problems and provide an overview of the results and the lessons learned.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Naived George Eapen ◽  
Debabrata Samanta ◽  
Manjit Kaur ◽  
Jehad F. Al-Amri ◽  
Mehedi Masud

The increase in computational power in recent years has opened a new door for image processing techniques. Three-dimensional object recognition, identification, pose estimation, and mapping are becoming popular. The need for real-world objects to be mapped into three-dimensional spatial representation is greatly increasing, especially considering the heap jump we obtained in the past decade in virtual reality and augmented reality. This paper discusses an algorithm to convert an array of captured images into estimated 3D coordinates of their external mappings. Elementary methods for generating three-dimensional models are also discussed. This framework will help the community in estimating three-dimensional coordinates of a convex-shaped object from a series of two-dimension images. The built model could be further processed for increasing the resemblance of the input object in terms of its shapes, contour, and texture.


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