189 research outputs found
Turbulent bands in a planar shear flow without walls
No full textThe banded structure of turbulence is observed immediately beyond transition in shear flows with two unconstrained directions (e.g. TCF, PCF, PPF). Yet despite its ubiquitous nature, the mechanisms underpinning bands are not understood to the level of localized turbulence in pipe flow. To this aim we investigate turbulent bands in Waleffe flow, a sinusoidal shear flow, U(y)=sin(pi/2 * y), with stress-free boundary conditions at y=+-1. The existence of turbulent bands in this system demonstrates that walls are not necessary to induce the phenomenon. The sinusoidal nature of the base forcing means the dominant features of bands can be viewed through a small number of Fourier modes in y. Utilizing this simple dependence we examine the emergence of turbulent bands from uniform turbulence
Vibrational assignment for the band system of the SiN radical: The 0-0 band of and
No full text1 Chikashi Yamada and Eizi Hirota, J. Chem. Phys. 82, 2547 (1985).Author Institution: Institute for Molecular Science; Nagoya UniversityThe vibrational assignment for the A-X system of the SiN was reexamined by observing the spectra in the region of and in natural abundance. The original assignment of Mulliken for the A state was found to be correct, rather than the one currently accepted; the spectrum was assigned to the 0-0 band of the A-X system. The vibrational and isotopic variations observed for the - type doubling and spin orbit interaction constants of the A state and for the spin-rotation interaction constants of the X state were explained by treating the electronic matrix elements of the spin-orbit interaction and of the orbital angular momentum between A/X, B/A and D/X states as parameters
Liquid Crystal Based Active Phase Modulator for Silicon Nitride Photonics Circuits at Near-Infrared
No full textWe demonstrate for the first-time voltage driven phase modulation with liquid crystal on SiN photonics at 874nm wavelength. We report a V pi L pi 0.72 V. cm with a loss of 1.8 dB/cm. (C) 2020 The Author(s)We demonstrate for the first-time voltage driven phase modulation with liquid crystal on SiN photonics at 874nm wavelength. We report a V pi L pi 0.72 V. cm with a loss of 1.8 dB/cm. (C) 2020 The Author(s)
Single spin asymmetry in pi p Drell-Yan process
No full textWe study the single spin asymmetries for the pi p(up arrow) -> mu(+)mu(-)x process. We consider the asymmetries contributed by the coupling of the Boer-Mulders function with the transversity distribution and the pretzelosity distribution, characterized by the sin(phi + phi s) and sin(3 phi - phi s) azimuthal angular dependence, respectively. We estimate the magnitude of these asymmetries at COMPASS by using proper weighting functions. We find that the sin(phi + phi s) asymmetry is of the size of a few percent and can be measured through the experiment. The sin(3 phi - phi s) asymmetry is smaller than the sin(phi + phi s) asymmetry. After a cut on q(T). we succeed in enhancing the asymmetry. (C) 2011 Elsevier B.V. All rights reserved.Physics, MultidisciplinarySCI(E)0ARTICLE5513-51769
Biometric authentication with low cost microcontroller
No full textThe purpose of this report is to elaborate and build a low cost facial identification system based on microcontroller as a part of the security feature. The facial identification method in this project is for facial recognition and drowsiness detection. Facial identification serves as a security tool to check the status of a person while using the hardware or software application. This method is popular for attendance-taking system, driving system, iPhone X etc. There are quite a few popular software tools to carry out the facial identification such as OpenCV, Kairos, Amazon, Microsoft etc. Each of the software has their own advantages and disadvantages. For this project we are using the OpenCV to build the facial identification system due to its available resources and it has the potential to expand in future as it support multi-platform. The facial identification in this project is built on the low-cost controller Raspberry Pi 3. The capability and reliability of Raspberry Pi 3 to handle the facial identification through OpenCV enable the author to successfully deploy it in this the project. A series of experiments is carried out to identify the factors affecting the performance of facial identification with Raspberry Pi and OpenCV. Based on the results, the overall performance looks promising in security control area.Bachelor of Engineerin
Measurement of the gamma gamma -> pi(+)pi(-) and gamma gamma -> K(+)K(-) processes at energies of 2.4-4.1 GeV
No full textWe have measured pi(+)pi(-) and K(+)K(-) production in two-photon collisions using 87.7 fb(-1) of data collected with the Belle detector at the asymmetric energy e(+)e(-) collider KEKB. The cross sections are measured to high precision in the two-photon center-of-mass energy (W) range between 2.4 GeV < W < 4.1 GeV and angular region broken vertical bar cos theta*broken vertical bar < 0.6. The cross section ratio sigma(gamma gamma -> K(+)K(-))/sigma(gamma gamma -> pi(+)pi(-)) is measured to be 0.89 +/- 0.04(stat.)+/- 0.15(syst.) in the range of 3.0 GeV < W < 4.1 GeV, where the ratio is energy-independent. We observe a sin(-4)theta* behavior of the cross section in the same W range. Production of chi(c0) and chi(c2) mesons is observed in both gamma gamma -> pi(+)pi(-) and gamma gamma -> K(+)K(-) modes. (c) 2005 Elsevier B.V. All rights reserved.Physics, MultidisciplinarySCI(E)0ARTICLE1-239-4961
Algebraic intersection in regular polygons
No full textNew version with the first author added and completely different methods. We focus on the case, the case is dealt with in a forthcoming paper by the first author. 30pages, 15 figuresWe study the function \mbox{KVol} : (X,\omega)\mapsto \mbox{Vol} (X,\omega) \sup_{\alpha,\beta} \frac{\mbox{Int} (\alpha,\beta)}{l_g (\alpha) l_g (\beta)} defined on the moduli spaces of translation surfaces. More precisely, let be the Teichm\"uller discs of the original Veech surface arising from right-angled triangle with angles by the unfolding construction for . For and any , we establish the (sharp) bounds \frac{n}{2} \cot \frac{\pi}{n} \leq \mbox{KVol}(X,\omega) \leq \frac{n}{2} \cot \frac{\pi}{n} \cdot \frac1{\sin \frac{2\pi}{n}}. The lower bound is uniquely realized at
Observation of the Singly Cabibbo-Suppressed Decay
No full textThe singly Cabibbo-suppressed decay is observed for the first time with a statistical
significance of by using 4.5 fb of collision data
collected at center-of-mass energies between 4.600 and 4.699 GeV with the
BESIII detector at BEPCII. The absolute branching fraction of
is measured to be in a model-independent approach. This is
the first observation of a Cabibbo-suppressed decay involving
in the final state. The ratio of branching fractions between
and the Cabibbo-favored decay
is calculated to be , where with the
Cabibbo mixing angle. This ratio significantly deviates from and
provides important information for the understanding of nonfactorization
contributions in decays.Comment: 8 pages, 2 figure
Nucleon transversity distribution from azimuthal spin asymmetry in pion electroproduction
No full textThe azimuthal asymmetry observed by the HERMES Collaboration in semi-inclusive pion production in deep inelastic scattering of an unpolarized positron on a longitudinally polarized proton target can provide information on the quark transversity distributions of the nucleon. We show that the quark transversity distributions predicted by both the light-cone quark spectator-diquark model and a PQCD inspired model can give consistent descriptions of the available HERMES data for the analyzing powers A(UL)(sin phi) and A(UL)(sin) (2 phi) for pi (+) and pi (-) productions. We also show that the two models give similar predictions of A(UL)(sin) (phi) for pi (+) production, whereas they give very different predictions of A(UL)(sin) (phi) for pi (-) production at large x. Further precision measurement of A(UL)(sin) (phi) for pi (-) production can provide a decisive test of different models.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000166750100058&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Astronomy & AstrophysicsPhysics, Particles & FieldsSCI(E)42ARTICLE3null6
Evaluation of oral stereognosis in completely edentulous patients with palatal tori
No full textBackground: The corollary is not investigated in the completely edentulous patients with palatal tori. Objective: The aim of this study was to assess the oral stereognostic ability in completely edentulous patients with palatal tori. Material and Methods: Thirty-four completely edentulous patients aged 50 to 89 years were allocated to Group 1 (without palatal tori, n=18) and Group 2 (with palatal tori, n=16). The oral stereognostic test was conducted using 6 intraoral test pieces (circle/square/rectangle/triangle/plus/toroid) that were fabricated to standard dimensions using the light cure acrylic resin. Each test piece was placed in the patient’s mouth and was asked to manipulate the test piece between the tongue and the palate. The patients identified the shapes by matching them on a shape chart. Each correct identification was assigned a score of 1. The response time taken to identify each shape was recorded. Statistical computation was done using a chi - square test and Mann-Whitney U test. Results: Significant difference was observed in the overall scoring percentages between the 2 groups (p<0.05). Group 2 had lower oral stereognostic scores compared to group 1 (p<0.05). There was no statistically significant difference in the mean response time for identifying the shapes among the groups, however group 2 patients had longer response time. Conclusion: Oral stereognostic ability of the completely edentulous patients with torus palatinus was lower when compared to completely edentulous patients without tori.Antecedentes: el corolario no se investiga en los pacientes completamente desdentados con toros palatinos. Objetivo: El objetivo de este estudio fue evaluar la capacidad estereognóstica oral en pacientes completamente edéntulos con toros palatinos. Material y Métodos: Treinta y cuatro pacientes completamente edéntulos de 50 a 89 años fueron asignados al Grupo 1 (sin toros palatinos, n = 18) y al Grupo 2 (con toros palatinos, n = 16). La prueba estereognóstica oral se realizó utilizando 6 piezas de prueba intraorales (círculo / cuadrado / rectángulo / triángulo / cruz / aro) que se fabricaron a dimensiones estándar utilizando la resina acrílica fotopolimerizable. Cada pieza de prueba se colocó en la boca del paciente y se le pidió que manipulara la pieza de prueba entre la lengua y el paladar. Los pacientes identificaron las formas haciéndolas coincidir en un gráfico de formas. A cada identificación correcta se le asignó una puntuación de 1. Se registró el tiempo de respuesta necesario para identificar cada forma. El cálculo estadístico se realizó mediante la prueba de chi-cuadrado y la prueba U de Mann-Whitney.Resultados: Se observó una diferencia significativa en los porcentajes de puntuación generales entre los 2 grupos (p<0,05). El grupo 2 tuvo puntuaciones estereognósticas orales más bajas en comparación con el grupo 1 (p<0,05). No hubo diferencia estadísticamente significativa en el tiempo medio de respuesta para identificar las formas entre los grupos, sin embargo, los pacientes del grupo 2 tuvieron un tiempo de respuesta más largo.Conclusión: La capacidad estereognóstica oral de los pacientes completamente edéntulos con torus palatino fue menor en comparación con los pacientes completamente edéntulos sin torus
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