scholarly journals Classification of real rational knots of low degree in the 3-sphere

2017 ◽  
Vol 26 (04) ◽  
pp. 1750020
Author(s):  
Shane D’Mello
Keyword(s):  
Double Point ◽  
Rational Curves ◽  
Low Degree ◽  
Ordinary Double Point ◽  
Rational Knots

In this paper, we classify, up to rigid isotopy, real rational knots of degrees less than or equal to [Formula: see text] in a real quadric homeomorphic to the 3-sphere. We also study their connections with rigid isotopy classes of real rational knots of low degree in [Formula: see text] and classify real rational curves of degree 6 in the 3-sphere with exactly one ordinary double point.

Geometric Characteristics of the Center-Point Curve Based on the Kinematics of the Compatibility Linkage

1992 ◽  
Author(s):  
J. A. Schaaf ◽  
J. A. Lammers
Keyword(s):  
Complex Number ◽  
Change Point ◽  
Double Point ◽  
Classification Scheme ◽  
Center Point ◽  
Degenerate Form ◽  
Point Curve ◽  
Position Synthesis ◽  
Point Form

Abstract In this paper we develop a method of characterizing the center-point curves for planar four-position synthesis. We predict the five characteristic shapes of the center-point curve using the kinematic classification of the compatibility linkage obtained from a complex number formulation for planar four-position synthesis. This classification scheme is more extensive than the conventional Grashof and non-Grashof classifications in that the separate classes of change point compatibility linkages are also included. A non-Grashof compatibility linkage generates a unicursal form of the center-point curve; a Grashof compatibility linkage generates a bicursal form; a single change point compatibility linkage generates a double point form; and a double or triple change point compatibility linkage generates a circular-degenerate or a hyperbolic-degenerate form.

scholarly journals RESEARCH OF RHEOLOGICAL PROPERTIES OF MEDICINAL SYRUP FOR ORAL USE

2020 ◽  
Vol 73 (4) ◽  
pp. 696-699
Author(s):  
Lena L. Davtian ◽  
Galyna P. Kukhtenko ◽  
Alona S. Voronkina ◽  
Viktoria V. Kudria
Keyword(s):  
Rheological Properties ◽  
Mechanical Stability ◽  
Rheological Parameters ◽  
Dynamic Flow ◽  
Shear Rates ◽  
Coaxial Cylinders ◽  
Low Degree ◽  
Newtonian Type ◽  
Rotary Viscometer

The aim of the present research was to investigate the rheological properties of the medicinal syrup for oral administration with glucosamine hydrochloride and levocarnitine. Matherials and methods: Coefficient of the dynamic flow (at shear rates of 3,49 and 10,3 s -1, as well as at shear rates of 27.2 and 149.0 s-1), mechanical stability, the index of destruction and restoration were studied. The rheological (structural-mechanical) properties of the samples were determined using a Rheolab QC rotary viscometer (AntonPaar, Austria) with coaxial cylinders CC27 / S-SN29766. The rheological parameters were studied at the temperature 20±0,5 °С. Results: It is established that the syrup has weakly expressed plastic viscous and thixotropic properties (the hysteresis area for the syrupis 1710.19 Pas/s). Such results characterize the system as a reopex. Conclusions: The results of the study enables classification of the research object as system with a low degree of fluidity. Such dependence is typical for systems of the Newtonian type of flow and characterizes the syrup under investigation as a weakly structured disperse system.

Study of recrystallization kinetics of aluminium alloy 1565ch with low degree of cast structure conditioning

2021 ◽  
pp. 58-64
Author(s):  
V. V. Yashin ◽  
◽  
I. A. Latushkin ◽  
E. S. Chitnaeva ◽  
E. V. Aryshensky ◽  
...  
Keyword(s):  
Temperature Drop ◽  
High Rate ◽  
Recrystallization Temperature ◽  
Growth Speed ◽  
Recrystallization Process ◽  
Russian Science ◽  
Cast Structure ◽  
Recrystallization Kinetics ◽  
Low Degree

The present study addresses recrystallization process in Al – Mg 1565ch system alloy samples (Russian classification). The samples are taken from cast ingot, produced by continuous casting in DC mold and homogenized based on standard commercial mode. Then the samples were heated to 350–500 oC and rolled in lab mill with different process schedules to cover the entire range of temperature and strain rates, applied in rolling. After rolling the samples were annealed at 350, 400 and 450 oC, their resultant microstructure was examined by optic microscope. The rate of new grains nucleation, their growth speed, analytical notations, describing recrystallization kinetics, were obtained within the frames of the study to be applied during this alloy recrystallization modelling; the main alloy-specific recrystallization features were identified and compared with alloy АА5182 (classification of American Aluminum Association). It is demonstrated, that 1565ch recrystallization has a number of specific features in case of as-cast structure deformation with low strain levels (ε = 0.14÷0.56): first, high rate of new grains nucleation; second, low grain growth speed to the extent of complete process blocking. Optimal recrystallization temperature is identified as 400 oC, at this temperature the process is over 75% complete, the temperature drop (350 oC) causes incubation period extension, while recrystallization subsides at recrystallized structure volume of about 30%, in case of temperature rise (450 oC) the structure is saturated with fine new grains nuclei, probably, emerging during heating, but due to high intensity of recovery and polygonization, recrystallization driving force drops to zero, the process stops with mixed structure and max recrystallized grains volume of 20%. This research was funded through a grant by the Russian Science Foundation, Project 18-79-10099.

Differences in the lexical variation of reporting verbs in French, English and Czech fiction and their impact on translation

2020 ◽  
Vol 20 (2) ◽  
pp. 209-234
Author(s):  
Olga Nádvorníková
Keyword(s):  
Target Language ◽  
Lexical Variation ◽  
Amount Of Information ◽  
Low Degree ◽  
Multilingual Corpus ◽  
High Degree

Abstract The aims of this paper are to analyse differences in the degree of lexical variation (type/token ratio and hapax/token ratio) of reporting verbs in reporting clauses placed medially or in postposition in English, French and Czech fiction and to evaluate their consequences in translation, especially in regard to explicitation/implicitation. We expect that, in translations from a language with a low degree of lexical variation of reporting verbs into a language with a high degree of lexical variation, the frequency and the degree of explicitation will be higher than in translations involving languages less different with respect to lexical variation. The analysis, relying on data extracted from the InterCorp multilingual corpus, proposes a classification of reporting verbs based on the type and amount of information conveyed, which allows evaluating the degree of explicitation operated in translations. The results show that most shifts involve only the neutral reporting verb say/dire, replaced by a stylistically more specific synonym or by a verb explicitating information obvious from the context. This suggests that modifications of reporting verbs in translation are motivated primarily by respect for the stylistic norm of the target language and the degree of acceptability of the repetition of the neutral reporting verb.

On certain types of isolated s-ple points on algebraic primals in Sd

1962 ◽  
Vol 58 (3) ◽  
pp. 465-475
Author(s):  
J. Herszberg
Keyword(s):  
Finite Number ◽  
Tangent Cone ◽  
Double Point ◽  
Complete Classification ◽  
Singular Points ◽  
Multiple Points ◽  
Rank Zero ◽  
Double Points

Singular points on irreducible primals were investigated briefly by C. Segre(8), where the author classified multiple points by the nature of the nodal tangent cone. For surfaces the problem of classification was investigated by, amongst others, Du Val(1) and a complete classification of isolated double points of surfaces lying on non-singular threefolds was given by Kirby(5). In (3) we classified certain types of double points on algebraic primals in Sn. An isolated double point which after a finite number of resolutions gave rise to at most a finite number of isolated double points was called a double point of rank zero. We found that the only isolated double points of rank zero are those which are analogous to the binodes, unodes and exceptional unodes (2) of surfaces.

Species complexes and the generic classification of leaf-litter thrips of the tribe Urothripini (Phlaeothripidae)

1972 ◽  
Vol 20 (1) ◽  
pp. 83 ◽  
Author(s):  
LA Mound
Keyword(s):  
Leaf Litter ◽  
Morphological Difference ◽  
Distinct Species ◽  
High Rate ◽  
Incipient Speciation ◽  
Species Complexes ◽  
Low Degree ◽  
Complicated Pattern ◽  
Pattern Of Variation

Collections of the predominantly wingless urothripine Thysanoptera from leaf litter in Australia show little variation in external morphology within any one population, although the variation between populations is frequently very considerable. Morphological segregates in which winged individuals are known show little variation between populations, and these segregates can be regarded as distinct species. However, morphological segregates in which winged individuals are not known exist in the field as a complex of similar but distinctive local forms. Taxonomy is concerned with the interpretation in biological terms of morphological difference, but the significance of these distinctive populations cannot be determined at present, whether they are species, subspecies, or local variants. However, this high rate of incipient speciation of the Urothripini is evidently related, at least in part, to the low degree of dispersive activity of the wingless forms. The resulting complicated pattern of variation at the species level is reflected in the unsatisfactory generic classification, and several of the characters which have been used for distinguishing genera are here shown to be of little value. As a result four genera, Bournieria, Ramachandraiella, Transithrips, and Verrucothrips, are here placed in synonymy with Baenothrips, and a key is provided to the remaining 13 genera of Urothripini from the world. An account is given of the eight species in five genera known from Australia, including two new species: Baenothrips caenosus (Stannard), comb. nov. ; Baenothrips moundi (Stannard), comb. nov. ; Biconothrips reedi Stannard; Habrothrips curiosus Ananthakrishnan; Octurothrips pulcher Priesner; Stephanothrips occidentalis Hood & Williams; S. barretti, sp, nov.; S. ferrari, sp. nov. In addition, knechteli Priesner is transferred to Amphibolothrips, comb. nov., and erythrinus Pelikan is transferred to Baenothrips, comb. nov.

scholarly journals Spaces of rational curves on complete intersections

2013 ◽  
Vol 149 (6) ◽  
pp. 1041-1060 ◽  
Author(s):  
Roya Beheshti ◽  
N. Mohan Kumar
Keyword(s):  
Complete Intersection ◽  
Rational Curves ◽  
Complete Intersections ◽  
Constant Dimension ◽  
Low Degree

AbstractWe prove that the space of smooth rational curves of degree $e$ on a general complete intersection of multidegree $(d_1, \ldots , d_m)$ in $\mathbb {P}^n$ is irreducible of the expected dimension if $\sum _{i=1}^m d_i \lt (2n+m+1)/3$ and $n$ is sufficiently large. This generalizes a result of Harris, Roth and Starr [Rational curves on hypersurfaces of low degree, J. Reine Angew. Math. 571 (2004), 73–106], and is achieved by proving that the space of conics passing through any point of a general complete intersection has constant dimension if $\sum _{i=1}^m d_i$ is small compared to $n$.

scholarly journals Hereditary Spherocytosis

Blood ◽  
1951 ◽  
Vol 6 (11) ◽  
pp. 1073-1098 ◽  
Author(s):  
LAWRENCE E. YOUNG ◽  
MARY JANE IZZO ◽  
RICHARD F. PLATZER
Keyword(s):  
Body Temperature ◽  
Gene Mutation ◽  
Hereditary Spherocytosis ◽  
Osmotic Fragility ◽  
Red Cells ◽  
Laboratory Findings ◽  
Low Degree ◽  
Qualitative Test ◽  
Chronic Hemolytic Anemia

Abstract Clinical, hematologic and genetic data on 28 cases of hereditary spherocytosis are presented for the purpose of characterizing this disorder as completely as possible. On the basis of this experience it is recommended that the following typical laboratory findings be sought in establishing a diagnosis in suspected cases: (1) Presence of spherocytes or abnormally thick red cells in peripheral blood; (2) greater than normal osmotic fragility of the red cells; in cases in which the fragility of fresh cells is not significantly increased, determinations should be made after sterile incubation of the blood at body temperature for 24 hours; (3) greater than normal mechanical fragility of freshly drawn red cells; (4) negative antiglobulin (Coombs) test; (5) greater than normal lysis of the red cells during sterile incubation at body temperature for 48 hours; and (6) presence of similar abnormalities in relatives. Abnormality of the erythrocyte persisted in all of the 11 patients in this series followed one or more years after splenectomy. An unusual case of chronic hemolytic anemia is described but not included in the numbered series because (1) both parents were hematologically normal and (2) spherocytosis and abnormally great osmotic and mechanical fragility and autohemolysis could not be demonstrated after the fifth postoperative month. Classification of this case is deferred pending further experience. Demonstration in a parent, sibling or offspring of red cells showing the afore-mentioned abnormalities is necessary for an unequivocal diagnosis, but this requirement cannot always be met because relatives may not be available for examination. Moreover, when parents and/or several siblings are examined without positive findings, low gene expressivity, gene mutation and illegitimacy may be considered as explanations. Evidence is cited to suggest the possibility of a low degree of penetrance or expression in some cases and to illustrate the need for still more sensitive laboratory tests that might aid in diagnosis of the mildest forms of this disease. The lower incidence of spherocytosis in siblings of propositi than in offspring of propositi is cited as evidence bearing on the theory of gene mutation in some propositi. A simplified "qualitative" test of osmotic fragility of incubated red cells is described.

scholarly journals Singular Curves of Low Degree and Multifiltrations from Osculating Spaces

2020 ◽  
Vol 2020 (21) ◽  
pp. 8139-8182 ◽  
Author(s):  
Jarosław Buczyński ◽  
Nathan Ilten ◽  
Emanuele Ventura
Keyword(s):  
Linear System ◽  
Smooth Curve ◽  
Rational Curves ◽  
Arithmetic Genus ◽  
Smooth Curves ◽  
Low Degree ◽  
Complete Linear System ◽  
Osculating Spaces ◽  
Special Case ◽  
Schubert Cycles

Abstract In order to study projections of smooth curves, we introduce multifiltrations obtained by combining flags of osculating spaces. We classify all configurations of singularities occurring for a projection of a smooth curve embedded by a complete linear system away from a projective linear space of dimension at most two. In particular, we determine all configurations of singularities of non-degenerate degree $d$ rational curves in $\mathbb{P}^n$ when $d-n\leq 3$ and $d<2n$. Along the way, we describe the Schubert cycles giving rise to these projections. We also reprove a special case of the Castelnuovo bound using these multifiltrations: under the assumption $d<2n$, the arithmetic genus of any non-degenerate degree $d$ curve in $\mathbb{P}^n$ is at most $d-n$.

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