Wyniki wyszukiwania - Biblioteka Nauki

1

A hybrid method for finite model search in equational

100%

Benhamou B. , Henocque L.

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1999

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tom Vol. 39, Nr 1,2

21-38

EN

Finite model and counter model generation is a potential alternative in automated theorem proving. In this paper, we introduce a system called FMSET which generates finite structures representing models of equational theories. FMSET performs a satisfiability test over a set of special first order clauses called ß clauses". The algorithm's originality stems from the combination of a standard enumeration technique and the use of first order resolution. Our objective is to obtain more propagations and still achieve good space and time complexity. Several experiments over a variety of problems have been pursued. FMSET uses symmetry to prune from the search tree unwanted isomorphic branches

2

New computer program to calculate the symmetry of molecules

100%

Ashrafi A. , Ahmadi M.

Open Chemistry

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2005

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tom 3

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nr 4

647-657

EN

In this paper we, present some MATLAB and GAP programs and use them to find the automorphism group of the Euclidean graph of the C80 fullerence with connectivity and geometry of Ih symmetry point group. It is proved that this group has order 120 and is isomorphic to Ih≊Z2×A5, where Z2 is, a cyclic group of order 2 and A5 is the alternating group on five symbols.

3

Minimality in asymmetry classes

100%

Wiernowolski M.

Studia Mathematica

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1997

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tom 124

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nr 2

149-154

EN

We examine minimality in asymmetry classes of convex compact sets with respect to inclusion. We prove that each class has a minimal element. Moreover, we show there is a connection between asymmetry classes and the Rådström-Hörmander lattice. This is used to present an alternative solution to the problem of minimality posed by G. Ewald and G. C. Shephard in [4].

4

The assessment of muscle strength symmetry in kayakers and canoeists

88%

Wietrzyński M. , Mazur-Różycka J. , Gajewski J. , Michalski R. , Różycki S. , Buśko K.

Biomedical Human Kinetics

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2013

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tom 5

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nr 1

65-71

EN

Study aim: To determine and compare the muscle strength profile and muscle strength symmetry of kayakers and canoeists. Material and methods: A total of 36 male participants participated in the study, including 25 kayakers and 9 canoeists. Measurements of maximum muscle torque were taken under static conditions for 10 muscle groups: flexors and extensors of the elbow, shoulder, knee, hip, and trunk. Muscle torque was allometrically scaled by body mass. To determine the muscle strength profiles of athletes in both disciplines, residual analysis was used. Two methods were utilized to assess and compare the muscle strength symmetry between left and right limbs. The first one is known as intraclass correlation coefficient (ICC). The second one is an asymmetry coefficient proposed by authors. Results: The study showed that kayakers obtained lower rates of asymmetry indicators than canoeists in most muscle groups. An overall asymmetry coefficient amounted to 0.77 ± 0.20 and 0.99 ± 0.31 (p < 0.05) for kayakers and canoeists, respectively. Moreover, it was observed that the kayakers and canoeists had similar strength profile. The symmetry assessment of maximum muscle torque corresponds to the characteristics of the studied disciplines. Conclusions: The intraclass correlation coefficient is recommended as a measure of strength symmetry for muscle groups comparisons. The asymmetry coefficient is recommended for comparison of individuals.

5

MR Brain Image Segmentation Using A Multi-seed Based Automatic Clustering Technique

88%

Saha S. , Bandyopadhyay S.

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2009

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tom Vol. 97, nr 1/2

199-214

EN

In this paper, the automatic segmentation of multispectral magnetic resonance image of the brain is posed as a clustering problem in the intensity space. Thereafter an automatic clustering technique is proposed to solve this problem. The proposed real-coded variable string length genetic clustering technique (MCVGAPS clustering) is able to evolve the number of clusters present in the data set automatically. Each cluster is divided into several small hyperspherical subclusters and the centers of all these small sub-clusters are encoded in a string to represent the whole clustering. For assigning points to different clusters, these local sub-clusters are considered individually. For the purpose of objective function evaluation, these sub-clusters are merged appropriately to form a variable number of global clusters. A recently developed point symmetry distance based cluster validity index, Sym-index, is optimized to automatically evolve the appropriate number of clusters present in an MR brain image. The proposed method is applied on several simulated T1-weighted, T2- weighted and proton density normal and MS lesion magnetic resonance brain images. Superiority of the proposed method over Fuzzy C-means, Expectation Maximization clustering algorithms are demonstrated quantitatively. The automatic segmentation obtained by multiseed based multiobjective clustering technique (MCVGAPS) is also compared with the available ground truth information.

6

Multiplication formulas for q-Appell polynomials and the multiple q-power sums

88%

Ernst T.

Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica

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2016

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tom 70

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nr 1

EN

In the first article on q-analogues of two Appell polynomials, the generalized Apostol-Bernoulli and Apostol-Euler polynomials, focus was on generalizations, symmetries, and complementary argument theorems. In this second article, we focus on a recent paper by Luo, and one paper on power sums by Wang and Wang. Most of the proofs are made by using generating functions, and the (multiple) q-addition plays a fundamental role. The introduction of the q-rational numbers in formulas with q-additions enables natural q-extension of vector forms of Raabes multiplication formulas. As special cases, new formulas for q-Bernoulli and q-Euler polynomials are obtained.

7

Selective symmetrization of the slip-system interaction matrix in crystal plasticity

88%

Petryk H. , Kursa M.

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2011

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tom Vol. 63, nr 3

287-287

EN

The symmetry issue of the interaction matrix between multiple slip-systems in the theory of crystal plasticity at finite deformation is revisited. By appealing to possibly non-uniform distribution of slip-system activity in a representative space-time element of a crystal, symmetry of the slip-system interaction matrix for the representative element is derived under assumptions that have a physical meaning. This conclusion refers to active slip-systems only. Accordingly, for any given hardening law, a new symmetrization rule is proposed that is restricted to active slip-systems and leaves the latent hardening of inactive slip-systems unchanged. Advantages of the proposal in comparison with full symmetrization are illustrated by a simple example of uniaxial tension.

8

Some Remarks on the Symmetry Kernel Test

88%

Baszczyńska A. , University of Lodz D. o. S. M.

|

2013

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tom 285

EN

The paper presents chosen statistical tests used to verify the hypothesis of the symmetry of random variable’s distribution. Detailed analysis of the symmetry kernel test is made. The properties of the regarded symmetry kernel test are compared with the other symmetry tests using Monte Carlo methods. The symmetry tests are used, as an example, in analysis of the distribution of the Human Development Index (HDI).

PL

W pracy przedstawiono wybrane statystyczne testy wykorzystywane w weryfikacji hipotezy o symetryczności rozkładu zmiennej losowej. Szczegółowej analizie poddano test symetryczności oparty o metodę jądrową. Porównano własności zaprezentowanych testów symetryczności oraz zastosowano je go analizy rozkładu wskaźnika rozwoju społecznego (HDI).

9

The bilateral strength and power asymmetries in untrained boys

75%

Maly T. , Zahalka F. , Mala L. , Cech P.

Open Medicine

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2014

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tom 10

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nr 1

EN

The aim of the study was to identify the level of isokinetic strength and power of lower limbs in 13-year- old untrained boys (n=22, height: 158.5±8.0 cm, mass: 49.1±12.6 kg), to determine bilateral deficit between the limbs in the tests and examine their mutual relationship. Maximum peak muscle torque of knee extensors (PTQ) and flexors (PTH) on dominant (DL) and non-dominant leg (NL) were measured by isokinetic dynamometer. Three types of a vertical jump: countermovement jump with (CMJFA) and without arms (CMJ) and squat jump (SJ) were performed on two force platforms. We found the significant effect (p<.01) of independent vari- ables (knee extensors, flexors, AV) and their interaction on PT. AV did not indicate any significant effect on bilat- eral ratio of knee extensors (F4,84=.74, p>.05, ηp2=0.03), however a significant effect of AV was found in knee flexors (F4,84=2.70,p<.05, ηp2=.114). The type of jump had no effect on the difference between force exerted by DL and NL (F1,21=.102, p>.05, ηp2=.01). Bilateral deficit (Q:Q, H:H) did not significantly correlate with bilateral deficit in jumps (p>.05). Despite the possibility of identifying muscle asymmetries in the sense of strength imbalances, their mutual relation- ship with results in isokinetic dynamometry and power jump tests is still unclear.

10

Invariance of integro-differential equations with moving region of integration

75%

Zawistowski Z. J.

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2006

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tom Vol. 47, no 2

103-112

EN

General criterion of invariance of integro-differential equations under the Lie symmetry group of point transformations is derived. It is a generalization of the previous form of the criterion to the case of a moving range of integration. This is the situation when a region of integration depends on external, with respect to integration, variables what leads to its explicit dependence on a group parameter, so the region of integration moves under symmetry transformations. General case of dependence on independent and dependent variables and their derivatives is considered.

11

Fuzzy Symmetry Based Real-Coded Genetic Clustering Technique for Automatic Pixel Classification in Remote Sensing Imagery

75%

Saha S. , Bandyopadhyay S.

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2008

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tom Vol. 84, nr 3-4

471-492

EN

The problem of classifying an image into different homogeneous regions is viewed as the task of clustering the pixels in the intensity space. In particular, satellite images contain landcover types some of which cover significantly large areas, while some (e.g., bridges and roads) occupy relatively much smaller regions. Automatically detecting regions or clusters of such widely varying sizes presents a challenging task. In this paper, a newly developed real-coded variable string length genetic fuzzy clustering technique with a new point symmetry distance is used for this purpose. The proposed algorithm is capable of automatically determining the number of segments present in an image. Here assignment of pixels to different clusters is done based on the point symmetry based distance rather than the Euclidean distance. The cluster centers are encoded in the chromosomes, and a newly developed fuzzy point symmetry distance based cluster validity index, FSym-index, is used as a measure of the validity of the corresponding partition. This validity index is able to correctly indicate presence of clusters of different sizes and shapes as long as they are internally symmetrical. The space and time complexities of the proposed algorithm are also derived. The effectiveness of the proposed technique is first demonstrated in identifying two small objects from a large background from an artificially generated image and then in identifying different landcover regions in remote sensing imagery. Results are compared with those obtained using the well known fuzzy C-means algorithm both qualitatively and quantitatively.

12

Witruwiańska harmonia form

75%

Kozaczko M.

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2009

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tom R. 106, z. 1-A

345-350

PL

Od niezliczonych pokoleń ludzkie reakcje na bodźce z otoczenia powtarzają się. Przekazywane genetycznie w więźbie aksonów są stale weryfikowane. Miara piękna, odbicie harmonii świata codziennie wdrukowuje się w strukturę mózgu. Przyjemność estetyczna jest zakorzeniona w najstarszych ewolucyjnie częściach mózgu i wyrasta z poczucia zadowolenia, z braku zagrożeń. W naszym umyśle tkwi wzorzec kompozycji idealnej - witruwiańskie venustas.

EN

Experiences, which have been concentrated and layered by thousands of generations in the inner being of man subsequently formed an ideal image of amicable environment, good composition and form. Human mind is a resonator of good form. The work of art built according to rules of such resonance contains visual truth about nature: venustas.

13

Geodesy and connectivity in lattices

75%

Ronse C. , Serra J.

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2001

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tom Vol. 46, nr 4

349-395

EN

This paper generalizes the notion of symmetrical neighbourhoods, which have been used to define connectivity in the case of sets, to the wider framework of complete lattices having a sup-generating family. Two versions (weak and strong) of the notion of a symmetrical dilation are introduced, and they are applied to the generation of ``connected components'' from the so-called ``geodesic dilations''. It turns out that any ``climbing'' ``weakly symmetrical'' extensive dilation induces a ``geodesic'' connectivity. When the lattice is the one of subsets of a metric space, the connectivities which are obtained in this way may coincide with the usual ones under some conditions, which are clarified. The abstract theory can be applied to grey-level and colour images, without any assumption of translation-invariance of operators.

14

THE APPLICABILITY OF USING PARAMETERS OF THE AUTOCORRELATION FUNCTION IN THE ASSESSMENT OF HUMAN BALANCE DURING QUIET BIPENDAL STANCE

75%

Stodółka J. , Korzewa L. , Stodółka W. , Gambal J.

Central European Journal of Sport Sciences and Medicine

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2017

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tom 17

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nr 1

79-87

EN

The purpose of the study was to analyze the parameters of the autocorrelation function when assessing time series ground reaction force (GRF) signals during quiet standing. GRF in the three directions were recorded on two Kistler force plates during three 15-s trials in a sample of 82 (31 females and 51 males) participants. Autocorrelation was performed on the GRF data and four parameters characterizing the function were computed. Comparisons of the right- and left-foot parameter means showed significant differences in mediolateral GRF for the time of the function's decay to 0, magnitude of the derivative output, and mean decay velocity to the extremum. Significant correlations were observed among all parameters – weak correlations between the time of the function's decay to 0 and the time to the first extremum and strong correlations between the derivative output and mean decay velocity to the extremum. The analyzed autocorrelation function parameters can serve as a precise measure of the motor control process during quiet standing. The strong correlations observed between the four parameters indicate that they evaluate similar properties of the central nervous system as a regulator of balance maintenance.

15

ВИВЧЕННЯ СТУДЕНТАМИ ДИНАМІЧНИХ СИМЕТРІЙ У ПРОЦЕСІ НАВЧАННЯ ЗАГАЛЬНОГО КУРСУ ФІЗИКИ У ВИЩИХ НАВЧАЛЬНИХ ЗАКЛАДАХ

63%

Кузьменко О. , Борота В.

Педагогічні науки: теорія, історія, інноваційні технології

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2015

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nr 7(51)

102-109

EN

One of directions of reformation of physics education in higher educational establishments is strengthening of its methodological orientation. The level of formation of students’ knowledge in physics is determined by mastering of fundamental physical concepts (for example, symmetry), laws, theories and principles. Actual question at the modern stage of development of physics education is the theory of symmetry, based on fundamental co-operations. The concept of symmetry that is fixed in basis of modern physical theories is analyzed in the article and examined. It is stressed that the theory of large association, based on principles of symmetry, is in the stage of development. The role of principles of invariance in physics is not yet out investigated, and we are distant from the universal natural law. Symmetry finds out connection of physical laws, simplifies understanding of difficult processes that flow in micro world and are examined in physics. The different types of dynamic symmetries are exposed in the article, such, as a gauge invariance, symmetry of identical particles, mirror and unitary symmetry, and also displace attention on a concept oddities of elementary particles, on that principle of isotopic is widespread. As a result of the conducted research it is established that expedience of submission of maintenance of educational material from physics is based on fundamental concepts, one of which is symmetry which is examined in many sections of physics. The idea of symmetry in a course of the study of physics needs to take into account didactics requirements, and also it is necessary for clarification and generalization of physical concepts, conformities to law. Accordingly an acquaintance and study of this concept by students will be instrumental in forming of modern scientific thought, and also will provide systematization of knowledge from the general course of physics in the university and forming of scientific world view, for providing of inter-subject connections. The prospects of subsequent searches in the direction of research consist in the detailed analysis of concept of symmetry in the process of study of general course of physics by students in higher educational establishments and development of method of studies of physics with the use of this concept.

16

Złożoność organiczna jako nowe ujęcie złożoności systemów ekonomicznych

63%

Wołoszyn P.

Zeszyty Naukowe Uniwersytetu Ekonomicznego w Krakowie

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2014

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nr 4(928)

143-157

PL

Systemy ekonomiczne i społeczne należą do szerokiej klasy systemów złożonych stanowiących przedmiot zainteresowania licznych dziedzin nauki. Istnieje wiele ujęć złożoności takich systemów różniących się sposobem definiowania i objaśniania źródeł skomplikowanych zachowań. Ponieważ złożoność jest jednak zjawiskiem powszechnym i w przyrodzie, wydaje się uzasadnione poszukiwanie pewnego uniwersalnego wzorca powtarzalnego we wszystkich rodzajach systemów złożonych. W artykule przedstawiono nową koncepcję złożoności organicznej rozumianej jako zespół trzech atrybutów: asymetrii, mnogości i interaktywności elementów systemu. System posiadający te cechy będzie dysponować zdolnością wytwarzania złożonych struktur lub zachowań. Prezentowane podejście może być przydatne w tworzeniu modeli ekonomicznych i społecznych systemów złożonych.

EN

Economic and social systems belong to a wide class of complex systems, the subject of research in many areas of science. There are many approaches to the complexity of such systems, which differ in how they define and explain the sources of complex behaviour. As complexity is widespread in nature, it seems legitimate to seek a universal pattern repeated in all kinds of complex systems. This article presents a new concept of organic complexity, understood as a set of three attributes: asymmetry, multiplicity and interactivity of a system’s components. Systems with these characteristics will have the ability to develop complex structures or behaviours. The organic complexity approach can be useful in building models of complex economic and social systems.

17

Symmetry of muscle activity during abdominal exercises

63%

Rutkowska-Kucharska A. , Szpala A. , Pieciuk E.

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2009

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tom Vol. 11, nr 1

25-30

EN

In this study, the symmetry of EMG activity of right and left parts of rectus abdominis, erector spinae, rectus femoris has been tested during isometric exercises. Subjects (N = 3) were selected from the university population. In each of nine isometric exercises, the position of lower and upper extremities is different in relation to the upper body. Electromyographic signals were recorded from left and right parts of selected muscles at 1000 Hz sampling frequency. Differences in EMG activity between specific exercises for left and right parts of each muscle were tested for significance with a one-way ANOVA. It was concluded that EMG activity of left and right sides of rectus abdominis and rectus femoris does not differ significantly; nevertheless statistically important differences were noticed between left and right sides of erector spine. These findings provide more detailed knowledge and understanding of different forms of abdominal exercises.

18

Gemini Residence - mieszkaniowy silos

63%

Galas M.

|

2009

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tom R. 106, z. 1-A

252-255

PL

Dziś reguły zastąpiono intuicyjnym poszukiwaniem form. Czy więc powrót do reguł jest możliwy? [1] Gemini Residence jawi się jako przykład budynku, w którym proporcje bryły, symetria, osiowość rozwiązania rzutów, rygorystyczna rytmika fasad, staranność podziałów sprawiają wrażenie, że budynek jest zaprojektowany według reguł - może tych opisanych przed wiekami?

EN

Nowadays, the rules have been replaced by the intuitive search of forms. Is it still possible to return to the rules? [1]. Gemini Residence seems to be an example of building which proportions of volums, symmetry, axial plans, rigorous rhythm of the faccades and modesty of divisions make an expression of following the rules - perhaps those descrived centuries ago?

19

W poszukiwaniu eurytmii

63%

Kozień-Wożniak M.

|

2009

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tom R. 106, z. 1-A

606-608

PL

Witruwiusz przyjmował obiektywne piękno, ale za konieczne uważał odstępstwa od niego, w imię subiektywnych warunków postrzegania piękna. Gdy symetria nie robi wrażenia eurytmii, trzeba ją przekształcić, aby dawała wrażenie eurytmiczne. Nie ma możliwości powrotu do dawnych reguł bez nowej ich interpretacji. Bez budowy reguł, które przeminą. Nie zmieni się tylko potrzeba eurytmii - wartości dodanej przez talent.

EN

Vitruvius recognized objective beauty, but he considered indispensable the defection from it - in the name of subjective perception of beauty. When symmetry does not make impression of eurytmia, it is necessary to transform it. Any forms are admitted today. There is no return to old rules without their new interpretations, new rules that inevitably will elapse. The need of eurytmia, a value added by talent remains.

20

On Macbeath-Singerman symmetries of Belyi surfaces with PSL(2,p) as a group of automorphisms

51%

Tyszkowska E.

Open Mathematics

|

2003

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tom 1

|

nr 2

208-220

EN

The famous theorem of Belyi states that the compact Riemann surface X can be defined over the number field if and only if X can be uniformized by a finite index subgroup Γ of a Fuchsian triangle group Λ. As a result such surfaces are now called Belyi surfaces. The groups PSL(2,q),q=p n are known to act as the groups of automorphisms on such surfaces. Certain aspects of such actions have been extensively studied in the literature. In this paper, we deal with symmetries. Singerman showed, using acertain result of Macbeath, that such surfaces admit a symmetry which we shall call in this paper the Macbeath-Singerman symmetry. A classical theorem by Harnack states that the set of fixed points of a symmetry of a Riemann surface X of genus g consists of k disjoint Jordan curves called ovals for some k ranging between 0 and g+1. In this paper we show that given an odd prime p, a Macbetah-Singerman symmetry of Belyi surface with PSL(2,p) as a group of automorphisms has at most