Finite-core hetons: stability and interactions

2000 ◽  
Vol 423 ◽  
pp. 127-154 ◽  
Author(s):  
M. A. SOKOLOVSKIY ◽  
J. VERRON

The dynamics of vertically compensated two-layer vortices (hetons) with finite cores are examined within the context of the quasi-geostrophic approximation on the f-plane. The two-layer version of the contour dynamics method is used, and complemented by the so-called contour surgery technique. Special attention is paid to two-heton interactions when the initial locations of the vortex patches are symmetrical. A classification of the different regimes observed is made according to external parameters, namely geometrical parameters and stratification. In this parameter space, novel quasi-stationary states resulting from collisions between two hetons may be observed: (i) formation of a configuration consisting of two-layer vortices moving in opposite directions and, as a special case, a configuration analogous to the ‘klapstoss’ billiard shot, (ii) absorption of one heton by the other and subsequent movement of a new dipole, (iii) formation of two-layer dipoles, larger than the original hetons, associated with rotating peripheral satellite eddies in their wakes. Some of these results may have implications for the analysis of mesoscale vortices in the ocean.

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 1-1
Author(s):  
B L Anderson

The classification of boundaries as figure and ground is one of the fundamental computations performed by the visual system. This computation requires classifying one side of a boundary, as an occluding or ‘intrinsic’ contour, and the other side of the contour as occluded or ‘extrinsic’ (also described as the problem of border ownership). A recent analysis of stereoscopic contour junctions revealed that the classification of edges as intrinsic or extrinsic to a neighbouring surface depends critically on the relative depth of the contours at the image junction. Specifically, it was argued that near edges are intrinsically one-sided (ie border ownership is uniquely specified by the junction geometry), whereas far contours are inherently two-sided (ie the border ownership of the far contour cannot be determined on the basis of the local junction geometry). Here I present new stimuli that reveal that the asymmetry of near and far contours in specifying border ownership reflects a more general asymmetry in the classification of near and far contrasts. A variety of stimuli were created. In one set of patterns, an array of five circular discs was embedded on a homogeneous background (either white or black) and was filled with a texture. A uniform disparity was added to the textured region such that it appeared nearer than the outer edges of the disc. When the power spectrum of the texture was systematically varied as functions of 1/ fn, the texture did not appear as a solid surface. Rather, the discs containing the texture gradients were decomposed into two sources: a constant background colour of the discs, and transparent clouds that appeared to float in front of the discs. Remarkably, the apparent colour of the clouds and the discs could be transformed simply by changing the colour of the background of the regions that neighboured the discs; the texture itself was unchanged. Specifically, when the textured discs were placed on white backgrounds, the pattern appeared as white clouds hovering in front of dark discs; but when the textured discs were placed on black backgrounds, the percept was of black ‘smoke’ hovering in front of white discs. It is argued that these results reveal that the problem of border ownership is a special case of contrast ownership. The two-sided qualities of far contrasts determine the colour of the background, which in turn determines which side of a near gradient is considered to be more or less opaque (ie which side is more occlusive).


2001 ◽  
Vol 8 (4/5) ◽  
pp. 301-311 ◽  
Author(s):  
V. Goncharov ◽  
V. Pavlov

Abstract. Multi-petal, rotating vortices can form in two-dimensional flows consisting of an inviscid incompressible fluid under certain conditions. Such vortices are principally nonlinear thermo-hydrodynamical structures. The proper rotation of these structures which leads to time-dependent variations of the associated temperature field can be enregistred by a stationary observer. The problem is analyzed in the framework of the contour dynamics method (CDM). An analytical solution of the reduced equation for a contour curvature is found. We give a classification of the solutions and compare the obtained results with observational data.


1997 ◽  
Vol 6 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Wayne O. Olsen ◽  
Terri L. Pratt ◽  
Christopher D. Bauch
Keyword(s):  

Multichannel ABR recordings for 30 otoneurologic patients were reviewed independently by three audiologists to assess interjudge consistency in determining absolute latencies and overall interpretation of ABR results. Four months later, the tracings were reviewed a second time to evaluate intrajudge consistency in interpretation of ABR waveforms. Interjudge agreement in marking latencies for waves I, III, and V within 0.2 ms was on the order of 90% or better. Intrajudge consistency was slightly higher. Only rarely did inter- or intrajudge differences in latency measurements exceed 0.3 ms. Agreement in overall interpretation of ABR results as "normal" or "abnormal" was unanimous for 90% of the patients. Across pairs of judges, the agreement for "normal" and "abnormal" classification of the ABR tracings was 97%. Intrajudge consistency for "normal" and "abnormal" categorization of the ABR results was 100% for one judge, 97% for the other two judges.


Author(s):  
I. R. Khuzina ◽  
V. N. Komarov

The paper considers a point of view, based on the conception of the broad understanding of taxons. According to this point of view, rhyncholites of the subgenus Dentatobeccus and Microbeccus are accepted to be synonymous with the genus Rhynchoteuthis, and subgenus Romanovichella is considered to be synonymous with the genus Palaeoteuthis. The criteria, exercising influence on the different approaches to the classification of rhyncholites, have been analyzed (such as age and individual variability, sexual dimorphism, pathological and teratological features, degree of disintegration of material), underestimation of which can lead to inaccuracy. Divestment of the subgenuses Dentatobeccus, Microbeccus and Romanovichella, possessing very bright morphological characteristics, to have an independent status and denomination to their synonyms, has been noted to be unjustified. An artificial system (any suggested variant) with all its minuses is a single probable system for rhyncholites. The main criteria, minimizing its negative sides and proving the separation of the new taxon, is an available mass-scale material. The narrow understanding of the genus, used in sensible limits, has been underlined to simplify the problem of the passing the view about the genus to the other investigators and recognition of rhyncholites for the practical tasks.


Author(s):  
I. Kukhtevich

Functional autonomic disorders occupy a significant part in the practice of neurologists and professionals of other specialties as well. However, there is no generally accepted classification of such disorders. In this paper the authors tried to show that functional autonomic pathology corresponds to the concept of somatoform disorders combining syndromes manifested by visceral, borderline psychopathological, neurological symptoms that do not have an organic basis. The relevance of the problem of somatoform disorders is that on the one hand many health professionals are not familiar enough with manifestations of borderline neuropsychiatric disorders, often forming functional autonomic disorders, and on the other hand they overestimate somatoform symptoms that are similar to somatic diseases.


ARTic ◽  
2019 ◽  
Vol 4 ◽  
pp. 167-176
Author(s):  
Risti Puspita Sari Hunowu

This research is aimed at studying the Hunto Sultan Amay Mosque located in Gorontalo City. Hunto Sultan Amay Mosque is the oldest mosque in the city of Gorontalo The Hunto Sultan Amay Mosque was built as proof of Sultan Amay's love for a daughter and is a representation of Islam in Gorontalo. Researchers will investigate the visual form of the Hunto Sultan Amay Mosque which was originally like an ancient mosque in the archipelago. can be seen from the shape of the roof which initially used an overlapping roof and then converted into a dome as well as mosques in the world, we can be sure the Hunto Sultan Amay Mosque uses a dome roof after the arrival of Dutch Colonial. The researcher used a qualitative method by observing the existing form in detail from the building of the mosque with an aesthetic approach, reviewing objects and selecting the selected ornament giving a classification of the shapes, so that the section became a reference for the author as research material. Based on the analysis of this thesis, the form  of the Hunto Sultan Amay mosque as well as the mosques located in the archipelago and the existence of ornaments in the Hunto Sultan Amay Mosque as a decorative structure support the grandeur of a mosque. On the other hand, Hunto Mosque ornaments reveal a teaching. The form of a teaching is manifested in the form of motives and does not depict living beings in a realist or naturalist manner. the decorative forms of the Hunto Sultan Sultan Mosque in general tend to lead to a form of flora, geometric ornaments, and ornament of calligraphy dominated by the distinctive colors of Islam, namely gold, white, red, yellow and green.


2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
Nishant Gupta ◽  
Nemani V. Suryanarayana

Abstract We construct classical theories for scalar fields in arbitrary Carroll spacetimes that are invariant under Carrollian diffeomorphisms and Weyl transformations. When the local symmetries are gauge fixed these theories become Carrollian conformal field theories. We show that generically there are at least two types of such theories: one in which only time derivatives of the fields appear and the other in which both space and time derivatives appear. A classification of such scalar field theories in three (and higher) dimensions up to two derivative order is provided. We show that only a special case of our theories arises in the ultra-relativistic limit of a covariant parent theory.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Giosuè Emanuele Muratore

Abstract The 2-Fano varieties, defined by De Jong and Starr, satisfy some higher-dimensional analogous properties of Fano varieties. We consider (weak) k-Fano varieties and conjecture the polyhedrality of the cone of pseudoeffective k-cycles for those varieties, in analogy with the case k = 1. Then we calculate some Betti numbers of a large class of k-Fano varieties to prove some special case of the conjecture. In particular, the conjecture is true for all 2-Fano varieties of index at least n − 2, and we complete the classification of weak 2-Fano varieties answering Questions 39 and 41 in [2].


Symmetry ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1077
Author(s):  
Yarema A. Prykarpatskyy

Dubrovin’s work on the classification of perturbed KdV-type equations is reanalyzed in detail via the gradient-holonomic integrability scheme, which was devised and developed jointly with Maxim Pavlov and collaborators some time ago. As a consequence of the reanalysis, one can show that Dubrovin’s criterion inherits important parts of the gradient-holonomic scheme properties, especially the necessary condition of suitably ordered reduction expansions with certain types of polynomial coefficients. In addition, we also analyze a special case of a new infinite hierarchy of Riemann-type hydrodynamical systems using a gradient-holonomic approach that was suggested jointly with M. Pavlov and collaborators. An infinite hierarchy of conservation laws, bi-Hamiltonian structure and the corresponding Lax-type representation are constructed for these systems.


2021 ◽  
Vol 7 (1) ◽  
pp. 200-222
Author(s):  
Hamada Hassanein ◽  
Mohammad Mahzari

Abstract This study has set out to identify, quantify, typify, and exemplify the discourse functions of canonical antonymy in Arabic paremiography by comparing two manually collected datasets from Egyptian and Saudi (Najdi) dialects. Building upon Jones’s (2002) most extensive and often-cited classification of the discourse functions of antonyms as they co-occur within syntactic frames in news discourse, the study has substantially revised this classification and developed a provisional and dynamic typology thereof. Two major textual functions are found to be quantitatively significant and qualitatively preponderant: ancillarity (wherein an A-pair of canonical antonyms project their antonymicity onto a more important B-pair) and coordination (wherein one antonym holds an inclusive or exhaustive relation to another antonym). Three new functions have been developed and added to the retrieved classification: subordination (wherein one antonym occurs in a subordinate clause while the other occurs in a main clause), case-marking (wherein two opposite cases are served by two antonyms), and replacement (wherein one antonym is substituted with another). Semicanonical and noncanonical guises of antonymy are left and recommended for future research.


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