Wyniki wyszukiwania - Biblioteka Nauki

1

Ellipse Invariant Algorithm for Texture Classification

100%

Yao C. C. , Lee K.

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2012

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tom Vol. 114, nr 2

203-220

EN

The classification of texture images, especially those with spatial rotation and region shift, is a challenge and important problem in image analysis and classification. This paper proposes a novel algorithm design, an ellipse invariant algorithm, to improve the capability of texture classification for spatial rotation and region shift. The principle of an ellipse invariant algorithm is to use a minimum ellipse to enclose specific representative pixels extracted by the subtracting clustering method. After translating the coordinates, the ellipse in the rotated texture would be formulated as the ellipse in original texture. Also in this paper a hybrid texture filter is proposed. In the hybrid texture filter the scheme of texture feature extraction include Gabor wavelet, neighboring grey level dependence matrix and the ellipse invariant algorithm. Support vector machines (SVMs) are introduced as the classifier. The proposed hybrid texture filter can classify both the stochastic textures and structural textures. Experimental results reveal that this proposed algorithm outperforms existing design algorithms.

2

Zakresy rotacji tułowia i miednicy u dziewcząt ze skoliozą idiopatyczną / A range of rotation of the trunk and pelvis in girls with idiopathic scoliosis

100%

Stępień A.

Advances in Rehabilitation

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2011

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tom 25

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nr 3

5-12

EN

Introduction: Mobility of spine in persons with different types of idiopathic scoliosis hasn’t been estimate. The aim of this study was to state the influence of scoliosis on a range of rotation of trunk and pelvis in adolescent girls with idiopathic scoliosis (AIS). Methods: 59 AIS girls at the age of 10-18 participated in the study. Right thoracic curve or left lumbar curve at spine radiography were the criteria for further measurements. Four groups including girls with different types of scoliosis were formed. Measurements were made in upright standing position The special designed prototype axial rotation tester with flip computer system was used to assess the range of rotation. The shoulder girdle with upper p of the trunk or the pelvis were fixed during tested rotation motions. The number and order motions were precisely determined in the study. 30 healthy girls without scoliosis were test as the control group. ANOVA test and T-test were used for statistical analyzes. Results: There are significant differences between the girls with double curve scoliosis with dominant right thoracic curve, the girls with single or double curve scoliosis with dominant left lumbar curve and the control group. Limited rotation of trunk and pelvis in horizontal plane were observed in the girls with double curve scoliosis with the dominant right thoracic curve. Increased rotation of pelvis in girls with single or double curve scoliosis with dominant left lumbar curve was found. Conclusions: A range of rotation of trunk and pelvis in girls with idiopathic scoliosis depends on a type of scoliosis, especially on location of dominant curve of scoliosis. A dominant right thoracic curve causes limitation of a range of rotation of trunk or pelvis and provokes asymmetries between a range of left and right rotation. A dominant left lumbar curve is conductive to increase a range of rotation of pelvis and provokes asymmetries between a range of left and right rotation.

3

NMR study on conformation of 2-Benzoyl-1-methyl-3-phenylpiperidine

100%

Szczeciński P. , Gryff-Keller A.

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2000

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tom Vol. 48, No. 1

13-18

EN

Temperature H NMR spectra of the title compound were measured and inter-preted in terms of slow rotation about the bond between piperidine ring and benzoyl sub-stituent. Barrier to this rotation was calculated to be Ea = 59 kJ/mol and log(A) = - 14.2.

4

Thermosolutal instability of Walters' (model B') visco-elastic rotating fluid permeated with suspended particles and variable gravity field in porous medium

88%

Sharma V. , Rana G. C.

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2001

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tom Vol. 6, no 4

843-860

EN

The thermosolutal instability of Walters' (model B') elastico-viscous rotating fluid in a porous medium is considered in the presence of a uniform rotation, suspended particles and variable gravity field. the stable solute gradient, rotation, gravity field, suspended particles and viscoelasticity introduce oscillatory modes. For the stationary convection, the stable gradient and rotation have stabilizing effects and suspended particles are found to have destabilizing effect on the system, whereas the medium permeability has destabilizing or stabilizing efect on the system under certain conditions. The effects of stable solute gradient, rotation, suspended particles, medium permeability have also been shown graphically.

5

Symmetropy of earthquake patterns: asymmetry and rotation in a disordered seismic source

88%

Nanjo K. , Nagahama H. , Yodogawa E.

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2006

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tom Vol. 54, no. 1

3-14

EN

We demonstrate that the idea of symmetropy can be used for quantification of earthquake patterns. The symmetropy can be considered as a measure of asymmetry. A pattern is richer in asymmetry when the symmetropy is smaller. The specific results of its applications are obtained as follows. In a discrete model of a seismic source with self-organized criticality, the spatial patterns of earthquakes during critical states and subcritical states are distinguished by the behaviour of the symmetropy: subcritical patterns show that the symmetropy is approximately a constant but this has various values during critical states. The critical patterns show asymmetric property without any asymmetric force from the outside and without asymmetric intracellular rule. We show that the emergence of asymmetric patterns is a generic feature of dynamic ruptures in our model. Such a generic asymmetry results from the model which is an inherently discrete system consisting of finite -sized cells. These cells may represent geometrical disordered fault zones. We further discuss rotational motions that generate seismic rotational waves. In micro-morphic continuum theory, such rotations are attributed to dynamic ruptures in dis-ordered systems. We note that the concept of disorder in this theory is expressed by a set of finite-sized microstructures and is consistent with the concept of disorder modelled in the present study. Thus, we suggest that the spatially asymmetric patterns of earthquakes might be related to the rotational motions, because both come from dynamic limit.

6

Effect of suspended particles and rotation on thermal instability of ferrofluids

75%

Aggarwal A. K. , Prakash K.

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2009

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tom Vol. 14, no 1

55-66

EN

This paper deals with the theoretical investigation of the effect of suspended particles on a rotating layer of a ferromagnetic fluid heated from below. For a fluid layer between two free boundaries, an exact solution is obtained using a linearized stability theory and normal mode analysis. For the case of stationary convection, it is found that suspended particles have a destabilizing effect, whereas rotation has a stabilizing effect on the onset of instability. The principle of exchange of stabilities is not valid for the problem under consideration, whereas in the absence of rotation it is valid under certain condition.

7

Hall effects on unsteady free convection slip flow in a rotating fluid along a porous vertical surface bounded by porous medium

75%

Jain N. C. , Gupta P.

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2007

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tom Vol. 12, no 3

609-627

EN

The present analysis is made to investigate the effects of Hall current on the free convection flow of an incompressible, viscous fluid through a porous medium in a rotating system past an infinite vertical porous plate in the presence of a heat sink and a transversely applied uniform magnetic field. Solutions of velocity and temperature fields are obtained using the perturbation technique. Expressions for the skin motion and heat transfer are also derived. It is found that the increase in the magnetic parameter (M) decreases both the primary skin friction [...] and secondary skin friction [...] while an increase in the Hall parameter (m) decreases [...] but increases [...].

8

Steady periodic regime of rotary motion of rollers in vibrating classifiers

75%

Ostapenko V. A. , Naduty V. P. , Yagnyukov V. F.

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2008

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tom Vol. 46 nr 1

157-169

EN

The problem of dynamics of vibrating classifiers with rollers intended for sorting of loose materials is considered in the paper. The main goal of research consists in substantiation of a choice of such parameters of rollers and classifiers which provide a steady periodic mode of rollers rotation. Differential equations of rollers rotation under action of inertial forces are essentially nonlinear. These equations are transformed to equations concerning the value of delay of moving rollers concerning rotation of axles on which these rollers are freely suspended. As values of such delays is small, the equations of motion can be linearized with a sufficient degree of accuracy. The linearized equations represent the inhomogeneous Hill equations, which can be under certain conditions transformed into the Mathieu equations. Periodic solutions to these equations are obtained, and also stability of these solutions is investigated.

PL

W pracy zaprezentowano problem dynamiki drgającego sortownika przeznaczonego do materiałów sypkich. Głównym celem analizy jest znalezienie i uzasadnienie takiego wyboru parametrów konstrukcyjnych sortownika, które zapewnią ustalony i okresowy stan pracy rolek. Równania ruchu są nieliniowe. W pracy dokonano przekształcenia równań tak, aby opisywały opóźnienie ruchu rolek w stosunku do rotacji względem osi, na których te rolki zamocowano. Przy niewielkich wartościach tego opóźnienia, równania ruchu mogą być zlinearyzowane z utrzymaniem wystarczającej dokładności. Linearyzacja prowadzi do równań Hilla, które przy spełnieniu pewnych warunków mogą zostać przekształcone do postaci Mathieu. W artykule przedstawiono rozwiązania tych równań oraz zbadano ich stabilność.

9

Effect of rotation on Rayleigh waves in an isotropic generalized thermoelastic diffusive half-space

75%

Kumar R. , Kansal T.

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2008

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tom Vol. 60, nr 5

421-443

EN

he present investigation is a study of the effect of rotation on the characteristics of Rayleigh waves propagation in a homogeneous, isotropic, thermoelastic diffusive half-space in the framework of different theories of thermoelastic diffusion, including the Coriolis and Centrifugal forces. The medium is subjected to stress-free, thermally insulated/isothermal and chemical potential boundary conditions and is rotating about an axis perpendicular to its plane. Secular equations of surface wave propagation in the considered media are derived. The phase velocities and attenuation coefficients of surface wave propagation have been computed by using the irreducible case of Cardano's method, with the help of DeMoivre's theorem known from the secular equations. The amplitudes of surface displacements, temperature change, concentration and the specific loss of energy are computed numerically. Rotation effect on the phase velocity, attenuation coefficient, amplitudes of surface wave propagation and specific loss of energy are presented graphically in order to illustrate and compare the analytically obtained results. Some special cases of frequency equation are also deduced from the present investigation.

10

Disturbance due to thermomechanical sources in a thermoviscoelastic medium with rotation

75%

Kumar R. , Garg S. K. , Ahuja S.

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tom Vol. 17, no. 1

127-141

EN

A dynamic problem in a thermoviscoelastic material with rotation is investigated for the disturbance due to thermomechanical sources. To solve the problem the Laplace and Fourier transform techniques are applied. Concentrated and uniformly distributed sources are taken as an application of the approach. A numerical inversion technique is used to invert the integral transform and to obtain the components of displacement, stress and temperature distribution in the physical domain. The effect of rotation and viscosity is examined on the resulting quantities and depicted graphically for a specific model .Some special case are also deduced from the present investigation.

11

Wpływ rotacji herbicydów na liczebność chwastów odpornych w monokulturze kukurydzy

63%

Kucharski M. , Sekutowski T.

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2007

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tom R. 11, nr 3 (91)

129-133

PL

Celem prowadzonych badań było określenie wpływu rotacji herbicydów na liczebność chwastów odpornych w monokulturze kukurydzy. W latach 2000-2004 prowadzono doświadczenie na plantacji kukurydzy, uprawianej od 1992 roku w monokulturze, którą corocznie odchwaszczano herbicydami triazynowymi. Na polu tym zidentyfikowano odporne na atrazynę Amaranthus retroflexus, Chenopodium album i Echinochloa crus-galli. W roku 2000 plantację podzielono na dwie części. Na jednej części nadal, corocznie stosowano herbicydy triazynowe, na drugiej zaś zmieniono dotychczas stosowane herbicydy na środki z grupy sulfonylomocznika. W roku 2004 obie części plantacji poddano ocenie stanu zachwaszczenia, z oznaczonych powierzchni pobrano próbki chwastów i metodą pomiaru fluorescencji określono liczebność osobników odpornych w poszczególnych zbiorowiskach. Uprawa kukurydzy w monokulturze oraz brak zmianowania herbicydów przyczyniły się do wystąpienia i rozwoju odporności biotypów Amaranthus retroflexus, Chenopodium album i Echinochloa crus-galli. Wprowadzenie rotacji herbicydów o różnym mechanizmie działania umożliwiło wzrost skuteczności zwalczania chwastów i ograniczyło liczebność osobników odpornych w populacji o około 8-15% w porównaniu do stanu z roku 2000.

EN

The aim of investigations was evaluation of herbicides rotation effect on variation of the number of resistant weed biotypes found in maize monoculture. Investigations were conducted on a maize field cultivated since 1992 as monoculture, where triazine herbicides were applied annually. In 2000 this field was divided into two blocks. On the first block application of triazine herbicides continued. On second block triazine herbicides were replaced by sulfonylurea herbicides. Using the fluorescence method on these fields the number of resistant weed biotypes was determined (Amaranthus retroflexus, Chenopodium album and Echinochloa crus-galli). After the four years the number of resistant biotypes was checked again. On the field, where triazine herbicides were applied, the increase of the number of resistant weeds was observed. Rotation of herbicides caused the decrease of the number of resistant weeds by 8-15% in comparison with the situation in 2000.

12

Effect of rotation on double-diffusive convection in a magnetized ferrofluid with internal angular momentum saturating a porous medium

63%

Sunil , Mahajan A.

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2008

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tom Vol. 13, no 4

1059-1078

EN

This paper deals with the theoretical investigation of the effect of rotation in a magnetized ferrofluid with internal angular momentum, heated and soluted from below saturating a porous medium and subjected to a transverse uniform magnetic field. For a flat fluid layer contained between two free boundaries, an exact solution is obtained. A linear stability analysis theory and normal mode analysis method have been employed to study the onset of convection. The influence of various parameters on the onset of stationary convection such as rotation, medium permeability, solute gradient, magnetization and internal angular momentum parameters (i.e., coupling parameter, spin diffusion parameter and heat conduction parameter) has been analyzed. The critical magnetic thermal Rayleigh number for the onset of instability is also determined numerically for sufficiently large values of buoyancy magnetization parameter and results are depicted graphically. The principle of exchange of stabilities is found to hold true for the ferrofluid with internal angular momentum saturating a porous medium heated from below in the absence of rotation, coupling between vorticity and spin, microinertia and solute gradient. The oscillatory modes are introduced due to the presence of the rotation, coupling between vorticity and spin, microinertia and solute gradient, which were non-existent in their absence. In this paper, an attempt is also made to obtain the sufficient conditions for the non-existence of overstability.

13

Deformation in a Generalized Thermoelastic Medium with Hydrostatic Initial Stress Subjected to Different Sources

63%

Ailawalia P. , Kumar S. , Khurana G.

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2009

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tom Vol. 13, nr 1

5-24

EN

In the present problem we study the deformation of a rotating generalized thermoelastic medium with hydrostatic initial stress subjected to three different type of sources. The components of displacement, force stress and temperature distribution are obtained in Laplace and Fourier domain by applying integral transforms. The general solution obtained is applied to a specific problem of a half-space subjected to concentrated force, distributed force and a moving source. These components are then obtained in the physical domain by applying a numerical inversion method. Some particular cases are also discussed in context of the problem. The results are also presented graphically to show the effect of rotation and hydrostatic initial stress.

14

Unsteady MHD Couette flow of class-II of a viscous incompressible electrically conducting fluid in a rotating system

63%

Seth G. S. , Singh J. K.

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tom Vol. 17, no. 2

495-512

EN

An unsteady hydromagnetic Couette flow of class-II of a viscous incompressible electrically conducting fluid in a rotating system is studied. The fluid flow within the channel is induced due to non-torsional oscillations of the upper plate of the channel. An exact solution of the governing equations is obtained by the Laplace transform technique. The numerical solution of the fluid velocity is depicted graphically whereas numerical values of shear stress at the plates are presented in a tabular form for various values of the magnetic parameter, rotation parameter and frequency parameter.

15

Effect of dust particles on a Soret- driven ferrothermohaline convection in a rotating medium

63%

Hemalatha R. , Sekar R. , Vaidyanathan G.

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tom Vol. 17, no. 2

367-381

EN

In ferrofluids three components namely, the core, surfactant and carrier fluids coexist. Thermal convection in a multicomponent fluid has wide applications in industrial, ionospheric and geothermal systems. In this paper the effect of dust particles on a Soret-driven ferrothermohaline convection in a rotating system heated and soluted from below subjected to a transverse uniform magnetic field is examined using linear stability analysis. An exact solution is obtained for the case of two free boundaries. Both stationary and oscillatory instabilities are investigated. The oscillatory modes are introduced due to the presence of dust particles, the stable solute gradient and rotation and the oscillatory modes are not allowed in their absence. In the case of stationary convection, the non-buoyancy magnetization parameter, the dust particle parameter destabilize the system. The Soret-coefficient, rotation and the stable solute gradient stabilize the system. The results are presented graphically.

16

Torque of the shank rotating muscles in patients with knee joint injuries

63%

Hrycyna M. , Zieliński J.

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tom Vol. 13, no. 4

77-83

EN

The aim of the study was to evaluate the torque of the shank rotating muscles in patients with reconstructed anterior cruciate ligament (ACL) and rehabilitation accomplished in comparison with a control group. The study was carried out on the group of 187 males. For the purpose of the study a prototype testing device for the shank rotating muscles' torque under static conditions was used. The study was based on the measurement of maximal torque at selected angles (-30 degree, 0 degree, 45 degree) of the shank rotation as well as on the angle (30 degree, 60 degree, 90 degree) of flexion of the knee joint. The results obtained in the group with reconstructed anterior cruciate ligament (ACL) and rehabilitation accomplished were comparable to those the control group and mostly of no statistical significance. Lack of significant differences between the values of shank rotating muscles' torque achieved in an injured limb compared to an uninjured one may testify to an effective rehabilitation process. The results of the research can serve as a diagnostic tool for the rehabilitation process development.

17

Effect of magnetic field dependent viscosity and rotation on ferrothermohaIine convection in the presence of dust particIes

63%

Sunil , Sharma A. , Shandil R. G.

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2007

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tom Vol. 12, no 1

197-213

EN

This paper deals with the theoretical investigation of the combined effect of magnetic field dependent (MFD) viscosity and rotation on ferrothermohaline convection in the presence of dust particles subjected to a transverse uniform magnetic field. For a flat fluid layer contained between two free boundaries, an exact solution is obtained using a linearized stability theory and normal mode analysis method. The cases of stationary convection and oscillatory modes have been discussed. In this paper, an attempt is also made to obtain the sufficient conditions for the non-existence of overstability.

18

Zdolności wyobrażeniowe niewidomych dzieci w zakresie skaningu i rotacji kształtu dotykanych obiektów

63%

Szubielska M.

Roczniki Psychologiczne

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2010

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tom 13

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nr 2

145-160

PL

W badaniach zaprezentowanych w artykule podjęto zagadnienie zdolności wyobrażeniowych niewidomych dzieci w zakresie skaningu i rotacji kształtu obiektów percypowanych dotykowo. Stwierdzono, że im starsze jest dziecko, tym lepiej różnicuje ono kształty dotykanych obiektów, ale jedynie w sytuacji, gdy kształty te względem siebie obrócono. Uzyskane wyniki wskazują na to, iż u niewidomych dzieci w okresie szkolnym doskonali się zdolność rotacji, zaś umiejętność skaningu jest osiągnięciem wcześniejszym rozwojowo. Zaobserwowano również, że trafność identyfikacji kształtu obiektów jest większa w sytuacji, gdy są one ustawione względem siebie w tej samej pozycji, niż gdy znajdują się w różnych pozycjach. Rotacja umysłowa stanowi więc dla niewidomych dzieci trudniejszą do wykonania operację wyobrażeniową niż skaning przestrzeni.

EN

The aim of the research was to explore the ability of spatial imagery in blind students, particularly their abilities to scan and mentally rotate tactile objects' shapes. The results demonstrate that the older the blind children are, the easier it is for them to differentiate shapes, but only in case when one of two objects is rotated. It may mean that the ability of mental rotation is developing during the school years, and the spatial scanning ability is achieved at an earlier age. It was also stated that identification of objects' shapes is more accurate in an aligned condition than in a rotated condition. It suggests that the mental rotation process is more complicated than the scanning process for blind children to perform.

19

Heat and mass transfer effects on rotating fluid past a moving vertical plate in the presence of radiation

63%

Vijayalakshmi A. R.

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tom Vol. 17, no. 1

299-307

EN

Thermal radiation effects on an unsteady free convection and mass transfer over a moving vertical plate in a rotating fluid are considered theoretically. An exact solution is obtained for the axial and transverse components of the velocity by defining complex velocity. The effects of velocity, temperature and concentration for different parameters such as radiation parameter, rotation parameter, Schmidt number, thermal Grashof number, mass Grashof number, Prandtl number and time on the plate are discussed.

20

Wykorzystanie sterownika PLC do kontroli ruchu silnika krokowego

51%

Mocny W.

|

2010

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tom Vol. 51, nr 7

97-99

PL

Artykuł dotyczy możliwości sterowania silnikiem krokowym przy wykorzystaniu najtańszej konfiguracji sprzętowej. Sterownik PLC połączony z prostym sterownikiem silnika krokowego.

EN

Communication refers to the stepper motor control using the least expensive hardvare configuration. Cheapest PLC combined with a simple stepper motor driver.