577 research outputs found
Oscillatory Behavior of Critical Amplitudes of the Gaussian Model on a Hierarchical Structure
We studied oscillatory behavior of critical amplitudes for the Gaussian model
on a hierarchical structure presented by a modified Sierpinski gasket lattice.
This model is known to display non-standard critical behavior on the lattice
under study. The leading singular behavior of the correlation length near
the critical coupling is modulated by a function which is periodic in
. We have also shown that the common finite-size scaling
hypothesis, according to which for a finite system at criticality should
be of the order of the size of system, is not applicable in this case. As a
consequence of this, the exact form of the leading singular behavior of
differs from the one described earlier (which was based on the finite-size
scaling assumption).Comment: 9 pages (REVTEX), 2 figures (EPS), Phys. Rev. E (accepted
Recommended from our members
Optomechanical conversion by mechanical turbines
Liquid crystal elastomers are rubbers with liquid crystal order. They contract along their nematic
director when heated or illuminated. The shape changes are large and occur in a relatively narrow
temperature interval, or at low illumination, around the nematicāisotropic transition. We present a
conceptual design of a mechanical, turbine-based engine using photo-active liquid crystal elastomers
to extract mechanical work from light. Its efficiency is estimated to be 40%.M. K. thanks the Winton Programme for the Physics of
Sustainability and the Cambridge International Trust for
financial support.This is the accepted manuscript. The final version is available from APS at http://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.2.044017
Dipole representation of half-filled Landau level
We introduce a variant of dipole representation for composite fermions in a
half-filled Landau level, taking into account the symmetry under exchange of
particles and holes. This is implemented by a special constraint on composite
fermion and composite hole degree of freedom (of an enlarged space), that makes
the resulting composite particle, dipole, a symmetric object. We study an
effective Hamiltonian, that commutes with the constraint on the physical space,
and fulfills the requirement for boost invariance on the Fermi level. The
calculated Fermi liquid parameter F2 is in a good agreement with numerical
investigations in [Phys. Rev. Lett. 121, 147601 (2018)].Comment: 9 pages, 4 figure
Orthodontic Treatment of Dentofacial Deformities
MeÄuÄeljusni nesklad stvara velike probleme pacijentima i estetski i funkcionalno. Razlog dolaska pacijenata u Kliniku uglavnom je estetske naravi, jer se radi o mlaÄim osobama, a funkicionalne su smjetnje u drugome planu. Uzimanje hrane, govor i disanje u takvih su osoba znatno otežani. Prikazat Äemo jedan od sluÄajeva lijeÄenje kombiniranoga dentofacijalnog deformiteta:
PROGNATHISMUS ET LATEROGNATHISMUS MANDIBULARIS.
Pacijentica, 34 godine. Iz anamnestiÄkih podataka nismo saznali da sliÄnih problema ima u obitelji. Motiv dolaska na Kliniku bio je estetske naravi, premda se je pacijentica žalila na bolove u oba Äeljusna zgloba, otežano uzimanje hrane i na neÅ”to teži izgovor pojedinih glasova.
Plan lijeÄenja donesen je na osnovi sljedeÄih potanko provedenih postupaka:
ā¢ raÅ”Älamba lica raÄena je na osnovi fotogarafija napravljenih iz profila i en face
ā¢ raÅ”Älamba okluzije uÄinjena je na studijskim modelima
ā¢ rentgenkefalometrijska raÅ”Älamba profilnog i AP kraniograma uÄinjena raÄunalom i ruÄno samo je potvrdila veÄ spomenutu dijagnozu
LijeÄenje je provedeno iskljuÄivo intraoralnom i ekstraoralnim ortodontskim napravama te smo smatrali korisnim iznijeti naÅ”a iskustva ovakvim naÄinom lijeÄenja.
Izgled pacijentice nakon lijeÄenja vidi se na slikama.
Ponovne kefalometrijske raÅ”Älambe raÄene su nakon zavrÅ”etka lijeÄenja. Svi parametri su u granicama normale, kako se vidi iz tabele s prikazanim vrijednostima prije i poslije lijeÄenja. RaÅ”Älambe mekih Äesti pacijentice takoÄer pokazuju znatne promjene, a odnosi nos, gornja usnica, donja usnica i brada veoma su dobri.
Dentofacijalni deformiteti danas se vrlo uspjeÅ”no rjeÅ”avaju. Dobre studijske raÅ”Älambe, na osnovi kojih se odreÄuje plan lijeÄenja, jamstvo su uspjeÅ”noga lijeÄenja. Vrlo malo je ostalo tajni u lijeÄenju dentofacijalnih deformiteta, ali ona od terapeuta traži visoku profesionalnost i uÄinkovitost.Disharmony of the jaws presents a great aesthetic and functional problem for patients. The reason for reporting to a clinic is mainly of an aesthetic nature, since most commonly young people are involved, while functional disturbances remain secondary. Such persons have difficulty eating, speaking and breathing. We will present one case of combined dentofacial deformity:
PROGNATHISMUS ET LATEROGNATHISMUS MANDIBULARIS.
Female patient, 34 years old. From anamnestic data we did not find out whether there were similar problems in the family. The motive for reporting to the clinic was aesthetics, although the patient complained of pain in both temporomandibular joints, difficulty eating and somewhat more difficult pronunciation of certain vocals.
A treatment plan was based on:
ā¢ Analysis of the face, based on profile and en face photographs.
ā¢ Analysis of occlusion, based on study models.
ā¢ Roentgen-cephalometry of the profile and AP craniogram, performed on a computer as well as manually, confirmed the above mentioned diagnosis.
The treatment was performed exclusively with intraoral and extraoral orthodontic appliances, and we therefore believe that it would be useful to present our experience with such a treatment method.
The appearance of the patient after treatment can be seen on the photographs. Repeated cephalometric analyses were performed after completion of the treatment. All parameters were within normal limits, as can be seen from the table presenting pre- and post treatment values. Analysis of the soft tissues also shows significant changes, and relations between the nose, upper lip, lower lip and chin are very good.
Today dentofacial deformities are successfully solved. Good study analyses, which serve as the base for planning treatment, guarantee successful treatment. There are very few secrets in ortognatic treatment, but it still requires high professionalism and effectivness
Numerical research of compressible turbulent swirl flow with energy separation in a cylindrical tube
Cilj ovog rada je numeriÄka analiza fenomena raslojavanja polja totalne temperature u turbulentnom stiÅ”ljivom vihornom strujanju u cilindriÄnoj cevi. U tom smislu, raslojavanje polja totalne temperature u vrtložnoj cevi sa potpuno zatvorenim otvorom za izlaz ohlaÄenog gasa se analizira numeriÄkim putem primenom softverom otvorenog tipa - OpenFOAM. Validacija dobijenih numeriÄkih rezultata je vrÅ”ena poreÄenjem sa vrednostima dobijenim eksperimentalnim putem. Za numeriÄke proraÄune koriste se dvojednaÄinski model (standardni k-Īµ) i puni naponski model turbulencije (LRR). ProraÄunski domen se smatra dvodimenzionalnim, a radni fluid - vazduh tretira se kao kaloriÄki idealni gas. Uticaj broja Äelija u mreži je izvrÅ”en pomoÄu Äetiri razliÄite veliÄine mreže. Raspodele jaÄine vihora, srednjeg vihora i ugaone brzine jasno ukazuju na uticaj prisustva vihora u strujnom polju. Sa druge strane, združeno sa njihovom vrednoÅ”Äu upuÄuju i na fiziku ovog izuzetno kompleksnog strujno-termodinamiÄkog fenomena kakav je fenomen raslojavanja polja totalne temperature. Na osnovu vrednosti i raspodela ovih strujnih veliÄina, izvrÅ”eno je i poreÄenje izmeÄu stiÅ”ljivog i nestiÅ”ljivog turbulentnog vihornog strujanja.The aim of this paper is to numerically analyze the energy separation phenomenon in turbulent compressible swirling flow in a cylindrical tube. In that sense, the energy separation in a vortex tube with orifice at cold end closed completely is examined numerically using OpenFOAM software. Obtained results are validated with the experimental ones. For numerical calculations, both two-equation (standard k-Īµ) and full Reynolds stress turbulence models (LRR) are used. The computational domain is considered to be two-dimensional, and the working fluid - air is treated as calorically perfect gas. Mesh independence test is carried out for four different mesh sizes. Distributions of swirling flow intensity, average swirl and angular velocity clearly show the influence of the swirl presence in the flow. The values of these quantities point to the physics of this extremely complex flow-thermodynamic phenomenon, such is the energy separation. Based on values and distributions of these flow quantities a comparison between incompressible and compressible turbulent swirling flow is performed
Numerical research of compressible turbulent swirl flow with energy separation in a cylindrical tube
Cilj ovog rada je numeriÄka analiza fenomena raslojavanja polja totalne temperature u turbulentnom stiÅ”ljivom vihornom strujanju u cilindriÄnoj cevi. U tom smislu, raslojavanje polja totalne temperature u vrtložnoj cevi sa potpuno zatvorenim otvorom za izlaz ohlaÄenog gasa se analizira numeriÄkim putem primenom softverom otvorenog tipa - OpenFOAM. Validacija dobijenih numeriÄkih rezultata je vrÅ”ena poreÄenjem sa vrednostima dobijenim eksperimentalnim putem. Za numeriÄke proraÄune koriste se dvojednaÄinski model (standardni k-Īµ) i puni naponski model turbulencije (LRR). ProraÄunski domen se smatra dvodimenzionalnim, a radni fluid - vazduh tretira se kao kaloriÄki idealni gas. Uticaj broja Äelija u mreži je izvrÅ”en pomoÄu Äetiri razliÄite veliÄine mreže. Raspodele jaÄine vihora, srednjeg vihora i ugaone brzine jasno ukazuju na uticaj prisustva vihora u strujnom polju. Sa druge strane, združeno sa njihovom vrednoÅ”Äu upuÄuju i na fiziku ovog izuzetno kompleksnog strujno-termodinamiÄkog fenomena kakav je fenomen raslojavanja polja totalne temperature. Na osnovu vrednosti i raspodela ovih strujnih veliÄina, izvrÅ”eno je i poreÄenje izmeÄu stiÅ”ljivog i nestiÅ”ljivog turbulentnog vihornog strujanja.The aim of this paper is to numerically analyze the energy separation phenomenon in turbulent compressible swirling flow in a cylindrical tube. In that sense, the energy separation in a vortex tube with orifice at cold end closed completely is examined numerically using OpenFOAM software. Obtained results are validated with the experimental ones. For numerical calculations, both two-equation (standard k-Īµ) and full Reynolds stress turbulence models (LRR) are used. The computational domain is considered to be two-dimensional, and the working fluid - air is treated as calorically perfect gas. Mesh independence test is carried out for four different mesh sizes. Distributions of swirling flow intensity, average swirl and angular velocity clearly show the influence of the swirl presence in the flow. The values of these quantities point to the physics of this extremely complex flow-thermodynamic phenomenon, such is the energy separation. Based on values and distributions of these flow quantities a comparison between incompressible and compressible turbulent swirling flow is performed
- ā¦