XWAS: A Software Toolset for Genetic Data Analysis and Association Studies of the X Chromosome.
Gao, Feng; Chang, Diana; Biddanda, Arjun; Ma, Li; Guo, Yingjie; Zhou, Zilu; Keinan, Alon
2015-01-01
XWAS is a new software suite for the analysis of the X chromosome in association studies and similar genetic studies. The X chromosome plays an important role in human disease and traits of many species, especially those with sexually dimorphic characteristics. Special attention needs to be given to its analysis due to the unique inheritance pattern, which leads to analytical complications that have resulted in the majority of genome-wide association studies (GWAS) either not considering X or mishandling it with toolsets that had been designed for non-sex chromosomes. We hence developed XWAS to fill the need for tools that are specially designed for analysis of X. Following extensive, stringent, and X-specific quality control, XWAS offers an array of statistical tests of association, including: 1) the standard test between a SNP (single nucleotide polymorphism) and disease risk, including after first stratifying individuals by sex, 2) a test for a differential effect of a SNP on disease between males and females, 3) motivated by X-inactivation, a test for higher variance of a trait in heterozygous females as compared with homozygous females, and 4) for all tests, a version that allows for combining evidence from all SNPs across a gene. We applied the toolset analysis pipeline to 16 GWAS datasets of immune-related disorders and 7 risk factors of coronary artery disease, and discovered several new X-linked genetic associations. XWAS will provide the tools and incentive for others to incorporate the X chromosome into GWAS and similar studies in any species with an XX/XY system, hence enabling discoveries of novel loci implicated in many diseases and in their sexual dimorphism. PMID:26268243
Redshift Space Distortions of the Correlation Function in Wide Angle Galaxy Surveys
Szalay, Alexander S.; Matsubara, Takahiko; Landy, Stephen D.
1997-01-01
Using a novel two-dimensional coordinate system, we have derived a particularly simple way to express the redshift distortions in galaxy redshift surveys with arbitrary geometry in closed form. This method provides an almost ideal way to measure the value of $\\beta=\\Omega_0^{0.6}/b$ in wide area surveys, since all pairs in the survey can be used for the analysis. In the limit of small angles, this result straightforwardly reduces to the plane-parallel approximation. This expansion can also be...
Future Constraints on Angle-Dependent Non-Gaussianity from Large Radio Surveys
Raccanelli, Alvise; Bartolo, Nicola; Bertacca, Daniele; Liguori, Michele; Matarrese, Sabino; Norris, Ray P; Parkinson, David
2015-01-01
We investigate how well future large-scale radio surveys could measure different shapes of primordial non-Gaussianity; in particular we focus on angle-dependent non-Gaussianity arising from primordial anisotropic sources, whose bispectrum has an angle dependence between the three wavevectors that is characterized by Legendre polynomials $\\mathcal{P}_L$ and expansion coefficients $c_L$. We provide forecasts for measurements of galaxy power spectrum, finding that Large-Scale Structure (LSS) data could allow measurements of primordial non-Gaussianity competitive or improving upon current constraints set by CMB experiments, for all the shapes considered. We argue that the best constraints will come from the possibility to assign redshift information to radio galaxy surveys, and investigate a few possible scenarios for the EMU and SKA surveys. A realistic (futuristic) modeling could provide constraints of $f_{\\rm NL}^{\\rm loc} \\approx 1 (0.5)$ for the local shape, $f_{\\rm NL}$ of $\\mathcal{O}(10) (\\mathcal{O}(1))$...
Topology Of Real And Angle Valued Maps And Graph Representations (A Brief Survey)
Burghelea, Dan
2012-01-01
(lecture delivered at the Congress of the Romanian mathematicians, Brasov, June 2011) Using graph representations a new class of computable topological invariants associated with a tame real or angle valued map were recently introduced, providing a theory which can be viewed as an alternative to Morse-Novicov theory for real or angle valued Morse maps. The invariants are "barcodes" and "Jordan cells". From them one can derive all familiar topological invariants which can be derived via Morse-...
Kyari, F; Abdull, MM; Wormald, R; Evans, Jr., Daw-Nay N. R.; Nolan, W; Murthy, GV; Gilbert, CE; Nigeria National Blindness and Visual Impairment Study Group; , COLLABORATORS; Imam, A.; Abiose, A; Ezelum, C; Entekume, G; Faal, H; Rabiu, M.
2016-01-01
The glaucoma-specific blindness prevalence in Nigeria (0.7 %, 95 % CI 0.6-0.9 %) among those aged ≥40 years is one of the highest ever reported. This study determined the risk factors for open-angle glaucoma (OAG) in adults examined in the Nigeria National Blindness and Visual Impairment Survey. A nationally representative sample of 13,591 people aged ≥40 years in 305 clusters in Nigeria were examined (response rate 90.4 %) between January 2005 to June 2007. Everyone had logMAR visual a...
Kyari, Fatima; Mohammed M Abdull; Wormald, Richard; Evans, Jennifer R.; Nolan, Winifred; Murthy, Gudlavelleti V. S.; Clare E Gilbert; ,; Imam, Abdullahi; Abiose, Adenike; Ezelum, Christian; Entekume, Gabriel; Faal, Hannah; Rabiu, Mansur M.; Bankole, Olufunmilayo O.
2016-01-01
Background The glaucoma-specific blindness prevalence in Nigeria (0.7 %, 95 % CI 0.6–0.9 %) among those aged ≥40 years is one of the highest ever reported. This study determined the risk factors for open-angle glaucoma (OAG) in adults examined in the Nigeria National Blindness and Visual Impairment Survey. Methods A nationally representative sample of 13,591 people aged ≥40 years in 305 clusters in Nigeria were examined (response rate 90.4 %) between January 2005 to June 2007. Everyone had lo...
Orlik-Ruckemann, K. J.
1973-01-01
A survey was conducted relative to future requirements for dynamic stability information for such aerospace vehicles as the space shuttle and advanced high performance military aircraft. High-angle-of-attack and high-Reynolds number conditions were emphasized. A review was made of the wind-tunnel capabilities in North America for measuring dynamic stability derivatives, revealing an almost total lack of capabilities that could satisfy these requirements. Recommendations are made regarding equipment that should be constructed to remedy this situation. A description is given of some of the more advanced existing capabilities, which can be used to at least partly satisfy immediate demands.
Nanostructure surveys of macroscopic specimens by small-angle scattering tensor tomography.
Liebi, Marianne; Georgiadis, Marios; Menzel, Andreas; Schneider, Philipp; Kohlbrecher, Joachim; Bunk, Oliver; Guizar-Sicairos, Manuel
2015-11-19
The mechanical properties of many materials are based on the macroscopic arrangement and orientation of their nanostructure. This nanostructure can be ordered over a range of length scales. In biology, the principle of hierarchical ordering is often used to maximize functionality, such as strength and robustness of the material, while minimizing weight and energy cost. Methods for nanoscale imaging provide direct visual access to the ultrastructure (nanoscale structure that is too small to be imaged using light microscopy), but the field of view is limited and does not easily allow a full correlative study of changes in the ultrastructure over a macroscopic sample. Other methods of probing ultrastructure ordering, such as small-angle scattering of X-rays or neutrons, can be applied to macroscopic samples; however, these scattering methods remain constrained to two-dimensional specimens or to isotropically oriented ultrastructures. These constraints limit the use of these methods for studying nanostructures with more complex orientation patterns, which are abundant in nature and materials science. Here, we introduce an imaging method that combines small-angle scattering with tensor tomography to probe nanoscale structures in three-dimensional macroscopic samples in a non-destructive way. We demonstrate the method by measuring the main orientation and the degree of orientation of nanoscale mineralized collagen fibrils in a human trabecula bone sample with a spatial resolution of 25 micrometres. Symmetries within the sample, such as the cylindrical symmetry commonly observed for mineralized collagen fibrils in bone, allow for tractable sampling requirements and numerical efficiency. Small-angle scattering tensor tomography is applicable to both biological and materials science specimens, and may be useful for understanding and characterizing smart or bio-inspired materials. Moreover, because the method is non-destructive, it is appropriate for in situ measurements and
Nanostructure surveys of macroscopic specimens by small-angle scattering tensor tomography
Liebi, Marianne; Georgiadis, Marios; Menzel, Andreas; Schneider, Philipp; Kohlbrecher, Joachim; Bunk, Oliver; Guizar-Sicairos, Manuel
2015-11-01
The mechanical properties of many materials are based on the macroscopic arrangement and orientation of their nanostructure. This nanostructure can be ordered over a range of length scales. In biology, the principle of hierarchical ordering is often used to maximize functionality, such as strength and robustness of the material, while minimizing weight and energy cost. Methods for nanoscale imaging provide direct visual access to the ultrastructure (nanoscale structure that is too small to be imaged using light microscopy), but the field of view is limited and does not easily allow a full correlative study of changes in the ultrastructure over a macroscopic sample. Other methods of probing ultrastructure ordering, such as small-angle scattering of X-rays or neutrons, can be applied to macroscopic samples; however, these scattering methods remain constrained to two-dimensional specimens or to isotropically oriented ultrastructures. These constraints limit the use of these methods for studying nanostructures with more complex orientation patterns, which are abundant in nature and materials science. Here, we introduce an imaging method that combines small-angle scattering with tensor tomography to probe nanoscale structures in three-dimensional macroscopic samples in a non-destructive way. We demonstrate the method by measuring the main orientation and the degree of orientation of nanoscale mineralized collagen fibrils in a human trabecula bone sample with a spatial resolution of 25 micrometres. Symmetries within the sample, such as the cylindrical symmetry commonly observed for mineralized collagen fibrils in bone, allow for tractable sampling requirements and numerical efficiency. Small-angle scattering tensor tomography is applicable to both biological and materials science specimens, and may be useful for understanding and characterizing smart or bio-inspired materials. Moreover, because the method is non-destructive, it is appropriate for in situ measurements and
Sánchez, Paul; Scheeres, Daniel J.
2016-06-01
This paper presents a study, through the use of a SSDEM simulation code, of the possible disruption patterns and mechanisms of self-gravitating aggregates that are spun-up to the point of disruption. We do this survey by systematically changing the angle of friction and tensile stress of the aggregates. It is observed that the amount of deformation that takes place before disruption, as well as its onset, is directly related to the angle of friction. On the other hand, the change in tensile strength allows us to clearly observe a continuous transition from losing surface material to larger scale fission at higher spin rates before disruption, but in no case do we observe surface flow. These results are also compared to other simulation results and the observations of asteroids P/2013 R3, P/2013 P5, 1950 DA, 1999 KW4 and Geographos. Additionally, we propose modifications to previously discussed mechanisms for the formation of binary asteroids and asteroid pairs.
Wide-angle seismic survey in the trench-outer rise region of the central Japan Trench
Fujie, G.; Kodaira, S.; Iwamaru, H.; Shirai, T.; Dannowski, A.; Thorwart, M.; Grevemeyer, I.; Morgan, J. P.
2015-12-01
Dehydration process within the subducting oceanic plate and expelled water from there affect various subduction-zone processes, including arc volcanism and generation of earthquakes. This implies that the degree of hydration within the incoming oceanic plate just prior to subduction might be a key control factor on the regional variations in subduction zone processes like interplate earthquakes and arc volcanism. Recent advances in seismic structure studies in the trench-outer rise region of the Japan Trench have revealed that seismic velocities within the incoming oceanic plate become lower owing to the plate bending-related faulting, suggesting the hydration of the oceanic plate. If the degree of the oceanic plate hydration is one of key factors controlling the regional variations of the interplate earthquakes, the degree of the oceanic plate hydration just prior to subduction is expected to show the along-trench variation because the interplate seismicity in the forearc region of the Japan Trench show along-trench variations. However, we cannot discuss the along-trench variation of the incoming plate structure because seismic structure studies have been confined only to the northern Japan Trench so far.In 2014 and 2015, JAMSTEC and GEOMAR conducted wide-angle seismic surveys in the trench-outer rise region of the central Japan Trench to reveal the detailed seismic structure of the incoming oceanic plate. The western extension of our survey line corresponds to the epicenter of the 2011 M9 Tohoku earthquakes. We deployed 88 Ocean Bottom Seismometers (OBSs) at intervals of 6 km and shot a tuned air-gun array of R/V Kairei at 200 m spacing. In this presentation, we will show the overview of our seismic survey and present seismic structure models obtained by the data of mainly 2014 seismic survey together with the several OBS data from 2015 survey. The preliminary results show P-wave velocity (Vp) within the oceanic crust and mantle decreases toward the trench axis
Kodaira, S.; Miura, S.; Smith, A. J.; Sato, T.; Tsuru, T.; Fujie, G.; Ito, A.; Takahashi, N.; Suyehiro, K.; Kaneda, Y.; Hino, R.; Mochizuki, K.; Kasahara, J.; Kanazawa, T.
2003-12-01
Recent progress of seismic wave form inversion revealed overlapping asperities of large earthquakes in the Japan Trench, e.g., the 1994 Sanriku-Haruka-Oki earthquake (M=7.5) and 1968 Tokachi-Oki earthquake (M=7.9). It is also recognized that the epicenters (initial break) of both earthquakes are situated at the trench-ward edge of the asperities, and the aftershocks were observed only around the asperities. Investigating structural factor controlling these asperity and seismicity pattern is believed to provide important and fundamental information to the physics of earthquakes. In August, 2003, we acquired wide-angle and multichannel seismic data covering the entire asperity region. The purpose of this study is to image structures of the asperity, and investigate the structures affecting the distribution of the seismicity pattern. Part of MCS data was processed onboard. We made CDP stacks by applying multiple suppression and poststack time migration. From the migration section of the dip profile, we recognized several key structures related to a subduction process; e.g., 1) the top of subducted oceanic crust can be traced up to 80 km from the trench axis. This reflector is recognized at 10 s twt to 70 km from the axis, rising up to 9s at 75 km then again down to 10 s farther than 75 km, 2) from 30 to 50km and 70 to 75 km, a weak reflector which is parallel to the top of the oceanic crust is identified. This might be the base of subducted crust, 3) located 35 to 45 km from the trench axis are several sub-parallel reflectors at 1 s above the top of the oceanic crust. These sub-parallel reflectors are also recognized at a central part of a strike profile, however there reflectors are not clear at the northern and southern end of the profile.
International Nuclear Information System (INIS)
The most commonly used methods of assessing the scoliotic deviation measure angles that are not clearly defined in relation to the anatomy of the patient. In order to give an anatomic basis for such measurements it is proposed to define the scoliotic deviation as the deviation the vertebral column makes with the sagittal plane. Both the Cobb and the Ferguson angles may be based on this definition. The present methods of measurement are then attempts to measure these angles. If the plane of these angles is parallel to the film, the measurement will be correct. Errors in the measurements may be incurred by the projection. A hypothetical projection, called a 'rectified orthogonal projection', is presented, which correctly represents all scoliotic angles in accordance with these principles. It can be constructed in practice with the aid of a computer and by performing measurements on two projections of the vertebral column; a scoliotic curve can be represented independent of the kyphosis and lordosis. (Auth.)
Discovery of a Very X-Ray Luminous Galaxy Cluster at Z=0.89 in the Wide Angle ROSAT Pointed Survey
Ebeling, H.; Jones, L. R.; Fairley, B. W.; Perlman, E.; Scharf, C.; Horner, D.
2001-02-01
We report the discovery of the galaxy cluster Cl J1226.9+3332 in the Wide Angle ROSAT Pointed Survey (WARPS). At z=0.888 and LX=1.1×1045 h-250 ergs s-1 (0.5-2.0 keV), Cl J1226.9+3332 is the most distant X-ray luminous cluster currently known. The mere existence of this system represents a huge problem for Ω0=1 world models. At the modest (off-axis) resolution of the ROSAT Position Sensitive Proportional Counter observation in which the system was detected, Cl J1226.9+3332 appears relaxed; an off-axis High Resolution Imager observation confirms this impression and rules out significant contamination from point sources. However, in moderately deep optical images (R and I band), the cluster exhibits signs of substructure in its apparent galaxy distribution. A first crude estimate of the velocity dispersion of the cluster galaxies based on six redshifts yields a high value of 1650 km s-1, indicative of a very massive cluster and/or the presence of substructure along the line of sight. While a more accurate assessment of the dynamical state of this system requires much better data at both optical and X-ray wavelengths, the high mass of the cluster has already been unambiguously confirmed by a very strong detection of the Sunyaev-Zeldovich effect in its direction. Using Cl J1226.9+3332 and Cl J0152.7-1357 (z=0.835), the second most distant X-ray luminous cluster currently known and also a WARPS discovery, we obtain a first estimate of the cluster X-ray luminosity function at 0.85×1044 h-250 ergs s-1 (0.5-2.0 keV). Using the best currently available data, we find the comoving space density of very distant, massive clusters to be in excellent agreement with the value measured locally (zconflict with earlier claims of highly significant (>3 σ) negative evolution already at 0.3team. Our findings are also consistent with the abundance of very X-ray luminous clusters at z~0.8 inferred from the EMSS cluster sample, provided Cl J0152.7-1357 (which was missed by the EMSS) is
DEFF Research Database (Denmark)
Sparrevohn, Claus Reedtz; Nielsen, Jan; Storr-Paulsen, Marie
all recreational fishermen have to purchase a personal non-transferable and time limited national license before fishing. However, this list will not include those fishing illegally without a license. Therefore, two types of recall surveys with their own questionnaires and group of respondents were...
Wallington, Sherrie Flynt; Blake, Kelly; Taylor-Clark, Kalahn; Viswanath, K
2010-01-01
The influence of news media on audience cognitions, attitudes, and behaviors in the realm of politics, race relations, science, and health has been extensively documented.Agenda setting and framing studies show that news media influence how people develop schema and place priorities on issues, with media stories serving as a major source of issue frames. Although news media are an important intermediary in the translation of scientific knowledge to different publics, little has been documented about the production of health news and factors that may predict media agenda setting and framing in health journalism. We used data from a 2005 national survey of U.S. health reporters and editors to examine predictors of source, resource, story angle, and frame usage among reporters and editors by variables such as organizational structure, individual characteristics of respondents (such as education and years working as a journalist),and perceptions of occupational autonomy. Multivariable logistic regression models revealed several differences among U.S. health reports and editors in the likelihood of using a variety of news sources, resources, priorities, and angles in reporting. Media agenda setting and framing theories suggest that practitioners familiar with media processes can work with journalists to frame messages, thereby increasing the probability of accurate and effective reporting. Results from this study may help to inform interactions between public health and medical practitioners and the press [corrected]. PMID:20390978
Perception of perspective angles
Erkelens, C.J.
2015-01-01
We perceive perspective angles, that is, angles that have an orientation in depth, differently from what they are in physical space. Extreme examples are angles between rails of a railway line or between lane dividers of a long and straight road. In this study, subjects judged perspective angles bet
Klingelhoefer, Frauke; Ladage, S; Dessa, J -X; Graindorge, David; Franke, D; André, C; Permana, Haryadi; Yudistira, T; Chauhan, Ajay; 10.1029/2009JB006569
2010-01-01
The 26 December 2004 Sumatra earthquake (Mw = 9.1) initiated around 30 km depth and ruptured 1300 km of the Indo-Australian Sunda plate boundary. During the Sumatra OBS (ocean bottom seismometer) survey, a wide angle seismic profile was acquired across the epicentral region. A seismic velocity model was obtained from combined travel time tomography and forward modeling. Together with reflection seismic data from the SeaCause II cruise, the deep structure of the source region of the great earthquake is revealed. Four to five kilometers of sediments overlie the oceanic crust at the trench, and the subducting slab can be imaged down to a depth of 35 km. We find a crystalline backstop 120 km from the trench axis, below the fore arc basin. A high velocity zone at the lower landward limit of the raycovered domain, at 22 km depth, marks a shallow continental Moho, 170 km from the trench. The deep structure obtained from the seismic data was used to construct a thermal model of the fore arc in order to predict the li...
Izard, Véronique; O'Donnell, Evan; Spelke, Elizabeth S.
2014-01-01
Preschool children can navigate by simple geometric maps of the environment, but the nature of the geometric relations they use in map reading remains unclear. Here, children were tested specifically on their sensitivity to angle. Forty-eight children (age 47:15-53:30 months) were presented with fragments of geometric maps, in which angle sections…
International Nuclear Information System (INIS)
The question of optimal projection angles has recently become of interest in the field of reconstruction from projections. Here, studies are concentrated on the n x n pixel space, where literative algorithms such as ART and direct matrix techniques due to Katz are considered. The best angles are determined in a Gauss--Markov statistical sense as well as with respect to a function-theoretical error bound. The possibility of making photon intensity a function of angle is also examined. Finally, the best angles to use in an ART-like algorithm are studied. A certain set of unequally spaced angles was found to be preferred in several contexts. 15 figures, 6 tables
Podzharenko, Volodymyr A.; Kulakov, Pavlo I.
2001-06-01
The photo-electric angle transmitter of rotation is offered, at which the output voltage is linear function of entering magnitude. In a transmitter the linear phototransducer is used on the basis of pair photo diode -- operating amplifier, which output voltage is linear function of the area of an illuminated photosensitive stratum, and modulator of a light stream of the special shape, which ensures a linear dependence of this area from an angle of rotation. The transmitter has good frequent properties and can be used for dynamic measurements of an angular velocity and angle of rotation, in systems of exact drives and systems of autocontrol.
Phase angle measurement techniques
Energy Technology Data Exchange (ETDEWEB)
Madge, R.; Fischer, D.
1996-01-01
Real-time measure of the power transfer across a transmission line was discussed. Phase angle measurement techniques, algorithms and applications relevant to power utilities were assessed. Phase-based applications compute the voltage angle difference between two stations, thereby allowing for power transfer calculations and power system control applications. A list of phase angle measurement applications was provided. It includes frequency measurement, state estimation, adaptive relaying, power system control, system restoration, real power flow monitoring and stability assessment, reactive power requirements monitoring, HVDC modulation, subsynchronous resonance, sequence of event recording, and loss reduction and fault location. The optimum timing requirement was determined for each application. Among the timing systems available today, the Global Positioning System (GPS), supported by powerful computers and other custom hardware, is the only tool that can provide the accuracy and coverage needed by today`s power system applications. Commercially available equipment for phase angle measurements was also reviewed. 30 refs., 32 tabs., 5 figs.
National Oceanic and Atmospheric Administration, Department of Commerce — The Billfish Angler Survey provides estimates of billfish angling activities in the Pacific and Indian Oceans. This collection of recreational billfish catch and...
DEFF Research Database (Denmark)
Miles, James Edward; Frederiksen, Jane V.; Jensen, Bente Rona;
2012-01-01
: Pelvic limbs from red foxes (Vulpes vulpes). METHODS: Q angles were measured on hip dysplasia (HD) and whole limb (WL) view radiographs of each limb between the acetabular rim, mid-point (Q1: patellar center, Q2: femoral trochlea), and tibial tuberosity. Errors of 0.5-2.0 mm at measurement landmarks...
1994-01-01
The Large Angle Magnetic Suspension Test Fixture (LAMSTF) is a 5 degree-of -freedom repulsive force magnetic suspension system designed to study the control of objects over large magnetic gaps. A digital control algorithm uses 6 sets of laser-sheet sensors and 5 control coils to position a cylinder 3' above the plane of electromagnetics
DEFF Research Database (Denmark)
Morgan, Jeannie; Lynnerup, Niels; Hoppa, R.D.
2013-01-01
measurements taken from computed tomography (CT) scans. Previous reports have observed that the lateral angle size in females is significantly larger than in males. The method was applied to an independent series of 77 postmortem CT scans (42 males, 35 females) to validate its accuracy and reliability. The...
Elementary engineering surveying
Ghosh, Jayanta Kumar
2010-01-01
Elementary Engineering Surveying is a text book for students attending the first course on Engineering Survey. The book is written very concisely and to the point for student to devout less time for study without compromising the quality of understanding and learning the elements of engineering survey. The book has eleven chapters prepared in modular form with an aim to carry out field surveying systematically. Starting from fundamentals of surveying, chapters include measurement of horizontal and vertical distances and angles, surveying instruments and their working with due importance to map
Schofield, W
2007-01-01
Engineering surveying involves determining the position of natural and man-made features on or beneath the Earth's surface and utilizing these features in the planning, design and construction of works. It is a critical part of any engineering project. Without an accurate understanding of the size, shape and nature of the site the project risks expensive and time-consuming errors or even catastrophic failure.Engineering Surveying 6th edition covers all the basic principles and practice of this complex subject and the authors bring expertise and clarity. Previous editions of this classic text have given readers a clear understanding of fundamentals such as vertical control, distance, angles and position right through to the most modern technologies, and this fully updated edition continues that tradition.This sixth edition includes:* An introduction to geodesy to facilitate greater understanding of satellite systems* A fully updated chapter on GPS, GLONASS and GALILEO for satellite positioning in surveying* Al...
Abelleira, J L; Bhat, C; Cornelis, K; De Maria, R; Fartoukh, S; Giachino, R; Holzer, E B; Lamont, M; Mastoridis, T; Macpherson, A; Papotti, G; Pieloni, T; Roncarolo, F; Roy, G; Salvachua, B; Valuch, D; Zimmermann, F; Ohmi, K
2012-01-01
Two high brightness bunches per beam were collided at injection energy with varying spectrometer strength in IP8 so that the corresponding Piwinski angle changed from about 1.2–1.3 to 0.2. One of the two bunches colliding in IP8 also collided in IPs 1 and 5, increasing its tune spread. A Piwinski angle of 1.2 is the biggest value ever achieved in a hadron collider. The goal of this experiemnt had been to investigate the influence of this parameter on the luminosity lifetime, beam lifetime and emittance growth rate. Due to technical problems and unavailability of luminosity signals from CMS this goal was only partially accomplished.
Nundy, Surajit; Lotto, Beau; Coppola, David; Shimpi, Amita; Purves, Dale
2000-01-01
Although it has long been apparent that observers tend to overestimate the magnitude of acute angles and underestimate obtuse ones, there is no consensus about why such distortions are seen. Geometrical modeling combined with psychophysical testing of human subjects indicates that these misperceptions are the result of an empirical strategy that resolves the inherent ambiguity of angular stimuli by generating percepts of the past significance of the stimulus rather than the geometry of its re...
Angle states in quantum mechanics
de la Torre, A. C.; Iguain, J. L.
1998-12-01
Angle states and angle operators are defined for a system with arbitrary angular momentum. They provide a reasonable formalization of the concept of angle provided that we accept that the angular orientation is quantized. The angle operator is the generator of boosts in angular momentum and is, almost everywhere, linearly related to the logarithm of the shift operator. Angle states for fermions and bosons behave differently under parity transformation.
Geometric structures on moment-angle manifolds
International Nuclear Information System (INIS)
A moment-angle complex ZK is a cell complex with a torus action constructed from a finite simplicial complex K. When this construction is applied to a triangulated sphere K or, in particular, to the boundary of a simplicial polytope, the result is a manifold. Moment-angle manifolds and complexes are central objects in toric topology, and currently are gaining much interest in homotopy theory and complex and symplectic geometry. The geometric aspects of the theory of moment-angle complexes are the main theme of this survey. Constructions of non-Kähler complex-analytic structures on moment-angle manifolds corresponding to polytopes and complete simplicial fans are reviewed, and invariants of these structures such as the Hodge numbers and Dolbeault cohomology rings are described. Symplectic and Lagrangian aspects of the theory are also of considerable interest. Moment-angle manifolds appear as level sets for quadratic Hamiltonians of torus actions, and can be used to construct new families of Hamiltonian-minimal Lagrangian submanifolds in a complex space, complex projective space, or toric varieties. Bibliography: 59 titles
Cerebellopontine angle Hodgkin's disease
International Nuclear Information System (INIS)
Intracranial Hodgkin's disease is a rare site of involvement, and even more rare is its presentation as a cerebellopontine angle mass. It can be difficult to diagnose especially when recurrent tumors occur because both CT and lumbar puncture have been shown to have a relatively low yield. Gadolinium-enhanced MRI is more sensitive. It is concluded that while the imaging findings can be non-specific, the rapid response to therapy (steroids) may provide a clue to diagnosis. Copyright (1999) Blackwell Science Pty Ltd
Critical angle laser refractometer
International Nuclear Information System (INIS)
A simple laser refractometer based on the detection of the critical angle for liquids is presented. The calibrated refractometer presents up to 0.000 11 of uncertainty when the refractive index is in the range between 1.300 00 and 1.340 00. The experimental setup is easy to construct and the material needed is available at most optics laboratories. The calibration method is simple and can be used in other devices. The refractive index measurements in aqueous solutions of sodium chloride were carried out to test the device and a linear dependence between the refractive index and the salt concentration was found
Variable angle correlation spectroscopy
International Nuclear Information System (INIS)
In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with 13C nuclei in rapidly rotating samples. These experiments focus on one of the basic problems in solid state NMR: how to extract the wealth of information contained in the anisotropic component of the NMR signal while still maintaining spectral resolution. Analysis of the anisotropic spectral patterns from poly-crystalline systems reveal information concerning molecular structure and dynamics, yet in all but the simplest of systems, the overlap of spectral patterns from chemically distinct sites renders the spectral analysis difficult if not impossible. One solution to this problem is to perform multi-dimensional experiments where the high-resolution, isotropic spectrum in one dimension is correlated with the anisotropic spectral patterns in the other dimensions. The VACSY technique incorporates the angle between the spinner axis and the static magnetic field as an experimental parameter that may be incremented during the course of the experiment to help correlate the isotropic and anisotropic components of the spectrum. The two-dimensional version of the VACSY experiments is used to extract the chemical shift anisotropy tensor values from multi-site organic molecules, study molecular dynamics in the intermediate time regime, and to examine the ordering properties of partially oriented samples. The VACSY technique is then extended to three-dimensional experiments to study slow molecular reorientations in a multi-site polymer system
Variable angle correlation spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Lee, Y K [Univ. of California, Berkeley, CA (United States)
1994-05-01
In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with {sup 13}C nuclei in rapidly rotating samples. These experiments focus on one of the basic problems in solid state NMR: how to extract the wealth of information contained in the anisotropic component of the NMR signal while still maintaining spectral resolution. Analysis of the anisotropic spectral patterns from poly-crystalline systems reveal information concerning molecular structure and dynamics, yet in all but the simplest of systems, the overlap of spectral patterns from chemically distinct sites renders the spectral analysis difficult if not impossible. One solution to this problem is to perform multi-dimensional experiments where the high-resolution, isotropic spectrum in one dimension is correlated with the anisotropic spectral patterns in the other dimensions. The VACSY technique incorporates the angle between the spinner axis and the static magnetic field as an experimental parameter that may be incremented during the course of the experiment to help correlate the isotropic and anisotropic components of the spectrum. The two-dimensional version of the VACSY experiments is used to extract the chemical shift anisotropy tensor values from multi-site organic molecules, study molecular dynamics in the intermediate time regime, and to examine the ordering properties of partially oriented samples. The VACSY technique is then extended to three-dimensional experiments to study slow molecular reorientations in a multi-site polymer system.
Angle performance on optima MDxt
International Nuclear Information System (INIS)
Angle control on medium current implanters is important due to the high angle-sensitivity of typical medium current implants, such as halo implants. On the Optima MDxt, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through six narrow slits, and any angle adjustment is made by electrostatically steering the beam, while cross-wafer beam parallelism is adjusted by changing the focus of the electrostatic parallelizing lens (P-lens). In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightly tilting the wafer platen prior to implant. A variety of tests were run to measure the accuracy and repeatability of Optima MDxt’s angle control. SIMS profiles of a high energy, channeling sensitive condition show both the cross-wafer angle uniformity, along with the small-angle resolution of the system. Angle repeatability was quantified by running a channeling sensitive implant as a regular monitor over a seven month period and measuring the sheet resistance-to-angle sensitivity. Even though crystal cut error was not controlled for in this case, when attributing all Rs variation to angle changes, the overall angle repeatability was measured as 0.16° (1σ). A separate angle repeatability test involved running a series of V-curves tests over a four month period using low crystal cut wafers selected from the same boule. The results of this test showed the angle repeatability to be <0.1° (1σ).
Williamson, Victoria J.; Müllensiefen, Daniel
2012-01-01
Involuntary, spontaneous cognitions are common, everyday experiences that occur against a backdrop of deliberate goal-directed mentation (Christoff, Ream & Gabrieli, 2004). One such phenomenon may hold special promise for empirical investigatio n of this often elusive experience. Involuntary musical imagery (IN MI) or ‘earworms’ are vivid, identifiable, and affect 91.7% of the population at least once a week (Liikkanen, 2012). tilizing an online survey instrument (http://earwormery.com/) we ...
Heterodyne Interferometer Angle Metrology
Hahn, Inseob; Weilert, Mark A.; Wang, Xu; Goullioud, Renaud
2010-01-01
A compact, high-resolution angle measurement instrument has been developed that is based on a heterodyne interferometer. The common-path heterodyne interferometer metrology is used to measure displacements of a reflective target surface. In the interferometer setup, an optical mask is used to sample the measurement laser beam reflecting back from a target surface. Angular rotations, around two orthogonal axes in a plane perpendicular to the measurement- beam propagation direction, are determined simultaneously from the relative displacement measurement of the target surface. The device is used in a tracking telescope system where pitch and yaw measurements of a flat mirror were simultaneously performed with a sensitivity of 0.1 nrad, per second, and a measuring range of 0.15 mrad at a working distance of an order of a meter. The nonlinearity of the device is also measured less than one percent over the measurement range.
Gaia: focus, straylight and basic angle
Mora, A; Bombrun, A; Boyadian, J; Chassat, F; Corberand, P; Davidson, M; Doyle, D; Escolar, D; Gielesen, W L M; Guilpain, T; Hernandez, J; Kirschner, V; Klioner, S A; Koeck, C; Laine, B; Lindegren, L; Serpell, E; Tatry, P; Thoral, P
2016-01-01
The Gaia all-sky astrometric survey is challenged by several issues affecting the spacecraft stability. Amongst them, we find the focus evolution, straylight and basic angle variations Contrary to pre-launch expectations, the image quality is continuously evolving, during commissioning and the nominal mission. Payload decontaminations and wavefront sensor assisted refocuses have been carried out to recover optimum performance. An ESA-Airbus DS working group analysed the straylight and basic angle issues and worked on a detailed root cause analysis. In parallel, the Gaia scientists have also analysed the data, most notably comparing the BAM signal to global astrometric solutions, with remarkable agreement. In this contribution, a status review of these issues will be provided, with emphasis on the mitigation schemes and the lessons learned for future space missions where extreme stability is a key requirement.
Small angle neutron scattering
Directory of Open Access Journals (Sweden)
Cousin Fabrice
2015-01-01
Full Text Available Small Angle Neutron Scattering (SANS is a technique that enables to probe the 3-D structure of materials on a typical size range lying from ∼ 1 nm up to ∼ a few 100 nm, the obtained information being statistically averaged on a sample whose volume is ∼ 1 cm3. This very rich technique enables to make a full structural characterization of a given object of nanometric dimensions (radius of gyration, shape, volume or mass, fractal dimension, specific area… through the determination of the form factor as well as the determination of the way objects are organized within in a continuous media, and therefore to describe interactions between them, through the determination of the structure factor. The specific properties of neutrons (possibility of tuning the scattering intensity by using the isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons make it particularly interesting in the fields of soft matter, biophysics, magnetic materials and metallurgy. In particular, the contrast variation methods allow to extract some informations that cannot be obtained by any other experimental techniques. This course is divided in two parts. The first one is devoted to the description of the principle of SANS: basics (formalism, coherent scattering/incoherent scattering, notion of elementary scatterer, form factor analysis (I(q→0, Guinier regime, intermediate regime, Porod regime, polydisperse system, structure factor analysis (2nd Virial coefficient, integral equations, characterization of aggregates, and contrast variation methods (how to create contrast in an homogeneous system, matching in ternary systems, extrapolation to zero concentration, Zero Averaged Contrast. It is illustrated by some representative examples. The second one describes the experimental aspects of SANS to guide user in its future experiments: description of SANS spectrometer, resolution of the spectrometer, optimization of
Small angle neutron scattering
International Nuclear Information System (INIS)
Small Angle Neutron Scattering (SANS) is a technique that enables to probe the 3-D structure of materials on a typical size range lying from about 1 nm up to a few 100 nm, the obtained information being statistically averaged on a sample whose volume is ∼ 1 cm3. This very rich technique enables to make a full structural characterization of a given object of nano-metric dimensions (radius of gyration, shape, volume or mass, fractal dimension, specific area... ) through the determination of the form factor as well as the determination of the way objects are organized within in a continuous media, and therefore to describe interactions between them, through the determination of the structure factor. The specific properties of neutrons (possibility of tuning the scattering intensity by using the isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons) make it particularly interesting in the fields of soft matter, biophysics, magnetic materials and metallurgy. In particular, the contrast variation methods allow to extract some information that cannot be obtained by any other experimental techniques. This course is divided in two parts. The first one is devoted to the description of the principle of SANS: basics (formalism, coherent scattering/incoherent scattering, notion of elementary scatterer), form factor analysis (I(q→0), Guinier regime, intermediate regime, Porod regime, polydisperse system), structure factor analysis (2. Virial coefficient, integral equations, characterization of aggregates), and contrast variation methods (how to create contrast in an homogeneous system, matching in ternary systems, extrapolation to zero concentration, Zero Averaged Contrast). It is illustrated by some representative examples. The second one describes the experimental aspects of SANS to guide user in its future experiments: description of SANS spectrometer, resolution of the spectrometer, optimization of spectrometer
Spinning angle optical calibration apparatus
Beer, Stephen K.; Pratt, II, Harold R.
1991-01-01
An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting an accurate reproducing of spinning "magic angles" in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the "magic angle" of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation or graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning "magic angle" of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position.
Calculations of the Wigner angle
International Nuclear Information System (INIS)
Two new methods to determine Wigner's angle in special relativity are presented. The first one consists in calculating the angle between the compositions u-bar x ν-bar and ν-bar x u-bar of the two non-collinear velocities u-bar and ν-bar. In another method we introduce a generalization in the complex plane of Einstein's addition law of parallel velocities. (author)
Rate Gyroscopic Wellbore Survey System
Institute of Scientific and Technical Information of China (English)
Sheng Limin
1997-01-01
@@ The rate gyroscopic wellbore survey system as a new type of survey instruments adopts the inertial-grade rate gyro and quartz flexible accelerometers to compose a gyrocompassing system, transiting data to surface instrument by single core cable. The azimuth, inclination and tool-face angle can be computed from these data by surface computer.
Johnson, Aylmer
2014-01-01
IntroductionAim And ScopeClassification Of SurveysThe Structure Of This BookGeneral Principles Of SurveyingErrorsRedundancyStiffnessAdjustmentPlanning And Record KeepingPrincipal Surveying ActivitiesEstablishing Control NetworksMappingSetting OutResectioningDeformation MonitoringAngle MeasurementThe Surveyor's CompassThe ClinometerThe Total StationMaking ObservationsChecks On Permanent AdjustmentsDistance MeasurementGeneralTape MeasurementsOptical Methods (Tachymetry)Electromagnetic Distance Measurement (EDM)Ultrasonic MethodsGNSSLevellingTheoryThe InstrumentTechniqueBookingPermanent Adjustmen
Wide angle redshift survey of the Hydra-Centaurus region
Energy Technology Data Exchange (ETDEWEB)
Fairall, A.P. (Cap Town Univ. (ZA). Dept. of Astronomy); Vettolani, G. (Consiglio Nazionale delle Ricerche, Bologna (IT). Gruppo Ricerche Spaziali); Chincarini, G. (Osservatorio di Brera, Milan (IT))
1989-05-01
Radial velocities for 266 galaxies in the region of Hydra Centaurus have been obtained. Examination of this preliminary sample allows a qualitative description of the large-scale distribution of galaxies in the region.
Frequency scaling for angle gathers
Zuberi, M. A H
2014-01-01
Angle gathers provide an extra dimension to analyze the velocity after migration. Space-shift and time shift-imaging conditions are two methods used to obtain angle gathers, but both are reasonably expensive. By scaling the time-lag axis of the time-shifted images, the computational cost of the time shift imaging condition can be considerably reduced. In imaging and more so Full waveform inversion, frequencydomain Helmholtz solvers are used more often to solve for the wavefields than conventional time domain extrapolators. In such cases, we do not need to extend the image, instead we scale the frequency axis of the frequency domain image to obtain the angle gathers more efficiently. Application on synthetic data demonstrate such features.
THE BEHAVIOR OF THE PITCH ANGLE OF SPIRAL ARMS DEPENDING ON OPTICAL WAVELENGTH
International Nuclear Information System (INIS)
Based on integral field spectroscopy data from the CALIFA survey, we investigate the possible dependence of spiral arm pitch angle with optical wavelength. For three of the five studied objects, the pitch angle gradually increases at longer wavelengths. This is not the case for two objects where the pitch angle remains constant. This result is confirmed by the analysis of SDSS data. We discuss the possible physical mechanisms to explain this phenomenon, as well as the implications of the results
Quantifying Stream Bed Gravel Mobility from Friction Angle Measurements
Meyers, M. A.; Dunne, T.
2012-12-01
A method to measure friction angles using force gauges was field tested to determine its utility at quantifying critical shear stress in a gravel bedded reach of the San Joaquin River in California. Predictions of mobility from friction angles were compared with observations of the movement of tagged particles from locations for which local shear stress was quantified with a validated 2-D flow model. The observations of movement, distance of travel, and location of the end of travel were made after extended flow releases from Friant dam. Determining the critical shear stress for gravel bed material transport currently depends upon bedload sampling or tracer studies. Often, such measurements can only be made during occasional and untimely flow events, and at limited, suboptimal locations. Yet, theoretical studies conclude that the friction angle is an important control on the critical shear stress for mobility of any grain size, and therefore of the excess shear stress which strongly influences bedload transport rate. The ability to predict bed mobility at ungauged and unmonitored locations is also an important requirement for planning of flow regimes and channel design. Therefore, a method to measure friction angles that can be performed quickly in low flow conditions would prove useful for river management and research. To investigate this promising method friction angle surveys were performed at two riffle sites where differences in bed material size and distribution, and channel slope were observed. The friction angle surveys are sensitive enough to detect differences between the sites as well as spatially and temporally within a single riffle. Low friction angles were observed along the inside of a long bend where sand content was greater (by ~20%) than other surveyed locations. Friction angles decreased slightly after a depositional event associated with transient large woody debris and bank erosion, and increased again after a 5 year return interval flow
Systematic variations in divergence angle
Okabe, Takuya
2012-01-01
Practical methods for quantitative analysis of radial and angular coordinates of leafy organs of vascular plants are presented and applied to published phyllotactic patterns of various real systems from young leaves on a shoot tip to florets on a flower head. The constancy of divergence angle is borne out with accuracy of less than a degree. It is shown that apparent fluctuations in divergence angle are in large part systematic variations caused by the invalid assumption of a fixed center and/or by secondary deformations, while random fluctuations are of minor importance.
Discovering the Inscribed Angle Theorem
Roscoe, Matt B.
2012-01-01
Learning to play tennis is difficult. It takes practice, but it also helps to have a coach--someone who gives tips and pointers but allows the freedom to play the game on one's own. Learning to act like a mathematician is a similar process. Students report that the process of proving the inscribed angle theorem is challenging and, at times,…
Contactless angle detection using permalloy
Eijkel, Kees J.; Rijk, Rolf
1988-01-01
An overview is given of measurements on angle detectors. The detectors consist of a pair of planar-Hall elements opposite to a rotatable magnet. The measurements are performed on a number of planar-Hall elements of different shape and size, and show good agreement with a previously described theoret
Oscillations of Relative Inclination Angles in Compact Extrasolar Planetary Systems
Becker, Juliette C
2015-01-01
The Kepler Mission has detected dozens of compact planetary systems with more than four transiting planets. This sample provides a collection of close-packed planetary systems with relatively little spread in the inclination angles of the inferred orbits. A large fraction of the observational sample contains limited multiplicity, begging the question whether there is a true diversity of multi transiting systems, or if some systems merely possess high mutual inclinations, allowing them to appear as single-transiting systems in a transit-based survey. This paper begins an exploration of the effectiveness of dynamical mechanisms in exciting orbital inclination within exoplanetary systems of this class. For these tightly packed systems, we determine that the orbital inclination angles are not spread out appreciably through self-excitation. In contrast, the two Kepler multi-planet systems with additional non-transiting planets are susceptible to oscillations of their inclination angles, which means their currently...
Disorders of the cerebellopontine angle
International Nuclear Information System (INIS)
Disorders of the cerebellopontine angle may present by symptoms like vertigo, hearing problems, affection of the trigeminal or facial nerve. Ipsilateral ataxia and contralateral hemiparesis develop in case of a rather large tumor in this region and display an involvement of the cerebellum and/or brainstem. However, some of these typical symptoms are not recognized by the patient. Thus, in case of a suspicion of a disorder of the cerebellopontine angle the relevant functions have to be tested clinically. In addition, electrophysiology can confirm dysfunction of these cranial nerves. Mainstay of the therapy should be the treatment of the underlying cause. Nevertheless, not seldom it is necessary to treat symptoms like vertigo or facial pain. (orig.)
DEFF Research Database (Denmark)
Jespersen, Søren Kragh; Wilhjelm, Jens Erik; Sillesen, Henrik
1998-01-01
This paper reports on a scanning technique, denoted multi-angle compound imaging (MACI), using spatial compounding. The MACI method also contains elements of frequency compounding, as the transmit frequency is lowered for the highest beam angles in order to reduce grating lobes. Compared to...... conventional B-mode imaging MACI offers better defined tissue boundaries and lower variance of the speckle pattern, resulting in an image with reduced random variations. Design and implementation of a compound imaging system is described, images of rubber tubes and porcine aorta are shown and effects on...... visualization are discussed. The speckle reduction is analyzed numerically and the results are found to be in excellent agreement with existing theory. An investigation of detectability of low-contrast lesions shows significant improvements compared to conventional imaging. Finally, possibilities for improving...
International Nuclear Information System (INIS)
The design, functioning, and main calibration, characteristics of a wide-angle detector, capable of recording electrons with energies >= 8 keV and insensitive to u.v. solar radiation are described. A description of the sensor (electron trap) and its electronics in the analog (DEGAFOC) and counting (DEGAFOI) modes is given. Examples of telemetry recordings, illustrating the operation of the detector are included. (Auth.)
Precision surveying the principles and geomatics practice
Ogundare, John Olusegun
2016-01-01
A comprehensive overview of high precision surveying, including recent developments in geomatics and their applications This book covers advanced precision surveying techniques, their proper use in engineering and geoscience projects, and their importance in the detailed analysis and evaluation of surveying projects. The early chapters review the fundamentals of precision surveying: the types of surveys; survey observations; standards and specifications; and accuracy assessments for angle, distance and position difference measurement systems. The book also covers network design and 3-D coordinating systems before discussing specialized topics such as structural and ground deformation monitoring techniques and analysis, mining surveys, tunneling surveys, and alignment surveys. Precision Surveying: The Principles and Geomatics Practice: * Covers structural and ground deformation monitoring analysis, advanced techniques in mining and tunneling surveys, and high precision alignment of engineering structures *...
Ocular Biometry in Angle Closure
Directory of Open Access Journals (Sweden)
Mohammad Reza Razeghinejad
2013-01-01
Full Text Available Purpose: To compare ocular biometric parameters in primary angle closure suspects (PACS, primary angle closure glaucoma (PACG and acute primary angle closure (APAC. Methods: This cross-sectional study was performed on 113 patients including 33 cases of PACS, 45 patients with PACG and 35 subjects with APAC. Central corneal thickness (CCT, axial length (AL, anterior chamber depth (ACD and lens thickness (LT were measured with an ultrasonic biometer. Lens-axial length factor (LAF, relative lens position, corrected ACD (CACD and corrected lens position were calculated. The parameters were measured bilaterally but only data from the right eyes were compared. In the APAC group, biometric parameters were also compared between affected and unaffected fellow eyes. Logistic regression analysis was performed to identify risk factors. Results: No statistically significant difference was observed in biometric parameters between PACS and PACG eyes, or between affected and fellow eyes in the APAC group (P>0.05 for all comparisons. However, eyes with APAC had thicker cornea (P=0.001, thicker lens (P<0.0001, shallower ACD (P=0.009, shallower CACD (P=0.003 and larger LAF (P<0.0001. Based on ROC curve analysis, lower ACD, and larger LT, LAF and CCT values were associated with APAC. In the APAC group, LAF (P<0.0001 and CCT (P=0.001 were significant risk factors. Conclusion: This study revealed no significant difference in biometric characteristics in eyes with PACS and PACG. However, larger LAF and CCT were predictive of APAC.
Small angle scattering and polymers
International Nuclear Information System (INIS)
The determination of polymer structure is a problem of interest for both statistical physics and industrial applications. The average polymer structure is defined. Then, it is shown why small angle scattering, associated with isotopic substitution, is very well suited to the measurement of the chain conformation. The corresponding example is the old, but pedagogic, measurement of the chain form factor in the polymer melt. The powerful contrast variation method is illustrated by a recent determination of the concentration profile of a polymer interface. (author) 12 figs., 48 refs
Opening Angles of Collapsar Jets
Mizuta, Akira; Ioka, Kunihito
2013-01-01
We investigate the jet propagation and breakout from the stellar progenitor for gamma-ray burst (GRB) collapsars by performing two-dimensional relativistic hydrodynamic simulations and analytical modeling. We find that the jet opening angle is given by $\\theta_j \\sim 1/5 \\Gamma_{0}$, and infer the initial Lorentz factor of the jet at the central engine, $\\Gamma_0$, is a few for existing observations of $\\theta_j$. The jet keeps the Lorentz factor low inside the star by converging cylindricall...
Small angle scattering and polymers
Energy Technology Data Exchange (ETDEWEB)
Cotton, J.P. [Laboratoire Leon Brillouin (LLB) - Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France)
1996-12-31
The determination of polymer structure is a problem of interest for both statistical physics and industrial applications. The average polymer structure is defined. Then, it is shown why small angle scattering, associated with isotopic substitution, is very well suited to the measurement of the chain conformation. The corresponding example is the old, but pedagogic, measurement of the chain form factor in the polymer melt. The powerful contrast variation method is illustrated by a recent determination of the concentration profile of a polymer interface. (author) 12 figs., 48 refs.
Small-angle neutron-scattering experiments
International Nuclear Information System (INIS)
A brief introduction to small-angle scattering (SAS) is given. Initial results obtained using the AERE small-angle diffractometer are presented for four materials of interest: doped uranium dioxide, nitrided steel, graphite and alumina. (U.K.)
The Complex Angle in Normed Spaces
International Nuclear Information System (INIS)
We consider a generalized angle in complex normed vector spaces. Its definition corresponds to the definition of the well known Euclidean angle in real inner product spaces. Not surprisingly it yields complex values as 'angles'. This 'angle' has some simple properties, which are known from the usual angle in real inner product spaces. But to do ordinary Euclidean geometry real angles are necessary. We show that even in a complex normed space there are many pure real valued 'angles'. The situation improves yet in inner product spaces. There we can use the known theory of orthogonal systems to find many pairs of vectors with real angles, and to do geometry which is based on the Greeks 2000 years ago
An Angle Criterion for Riesz Bases
DEFF Research Database (Denmark)
Lindner, Alexander M; Bittner, B.
We present a characterization of Riesz bases in terms ofthe angles between certain finite dimensional subspaces. Correlationsbetween the bounds of the Riesz basis and the size of the angles arederived....
Precision determination of electron scattering angle by differential nuclear recoil energy method
Energy Technology Data Exchange (ETDEWEB)
Liyanage, N.; Saenboonruang, K.
2015-12-01
The accurate determination of the scattered electron angle is crucial to electron scattering experiments, both with open-geometry large-acceptance spectrometers and ones with dipole-type magnetic spectrometers for electron detection. In particular, for small central-angle experiments using dipole-type magnetic spectrometers, in which surveys are used to measure the spectrometer angle with respect to the primary electron beam, the importance of the scattering angle determination is emphasized. However, given the complexities of large experiments and spectrometers, the accuracy of such surveys is limited and insufficient to meet demands of some experiments. In this article, we present a new technique for determination of the electron scattering angle based on an accurate measurement of the primary beam energy and the principle of differential nuclear recoil. This technique was used to determine the scattering angle for several experiments carried out at the Experimental Hall A, Jefferson Lab. Results have shown that the new technique greatly improved the accuracy of the angle determination compared to surveys.
The qualitative criterion of transient angle stability
Lyu, R; Xue, Y.; Xue, F; Wu, Qiuwei; Yang, Guangya; Zhou, H; Ju, P.
2015-01-01
In almost all the literatures, the qualitative assessment of transient angle stability extracts the angle information of generators based on the swing curve. As the angle (or angle difference) of concern and the threshold value rely strongly on the engineering experience, the validity and robust of these criterions are weak. Based on the stability mechanism from the extended equal area criterion (EEAC) theory and combining with abundant simulations of real system, this paper analyzes the crit...
Explicit angle structures for veering triangulations
Futer, David
2010-01-01
Agol recently introduced the notion of a veering triangulation, and showed that such triangulations naturally arise as layered triangulations of fibered hyperbolic 3-manifolds. We prove, by a constructive argument, that every veering triangulation admits positive angle structures, recovering a result of Hodgson, Rubinstein, Segerman, and Tillmann. Our construction leads to explicit lower bounds on the smallest angle in this positive angle structure, and to information about angled holonomy of the boundary tori.
Wide-angle tail galaxies in ATLAS
Mao, Minnie Y; Saikia, D J; Norris, Ray P; Johnston-Hollitt, Melanie; Middelberg, Enno; Lovell, Jim E J
2010-01-01
We present radio images of a sample of six Wide-Angle Tail (WAT) radio sources identified in the ATLAS 1.4 GHz radio survey, and new spectroscopic redshifts for four of these sources. These WATs are in the redshift range of 0.1469 - 0.3762, and we find evidence of galaxy overdensities in the vicinity of four of the WATs from either spectroscopic or photometric redshifts. We also present follow-up spectroscopic observations of the area surrounding the largest WAT, S1189, which is at a redshift of ~0.22. The spectroscopic observations, taken using the AAOmega spectrograph on the AAT, show an overdensity of galaxies at this redshift. The galaxies are spread over an unusually large area of ~12 Mpc with a velocity spread of ~4500 km/s. This large-scale structure includes a highly asymmetric FRI radio galaxy and also appears to host a radio relic. It may represent an unrelaxed system with different sub-structures interacting or merging with one another. We discuss the implications of these observations for future l...
30 CFR 56.19037 - Fleet angles.
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fleet angles. 56.19037 Section 56.19037 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Sheaves § 56.19037 Fleet angles. Fleet angles on hoists installed after November 15, 1979, shall not...
30 CFR 57.19037 - Fleet angles.
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fleet angles. 57.19037 Section 57.19037 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Sheaves § 57.19037 Fleet angles. Fleet angles on hoists installed after November 15, 1979, shall not...
Oscillations of relative inclination angles in compact extrasolar planetary systems
Becker, Juliette C.; Adams, Fred C.
2016-01-01
The Kepler mission has detected dozens of compact planetary systems with more than four transiting planets. This sample provides a collection of close-packed planetary systems with relatively little spread in the inclination angles of the inferred orbits. A large fraction of the observational sample contains limited multiplicity, begging the question whether there is a true diversity of multitransiting systems, or if some systems merely possess high mutual inclinations, allowing them to appear as single-transiting systems in a transit-based survey. This paper begins an exploration of the effectiveness of dynamical mechanisms in exciting orbital inclination within exoplanetary systems of this class. For these tightly packed systems, we determine that the orbital inclination angles are not spread out appreciably through self-excitation. In contrast, the two Kepler multiplanet systems with additional non-transiting planets are susceptible to oscillations of their inclination angles, which means their currently observed configurations could be due to planet-planet interactions alone. We also provide constraints and predictions for the expected transit duration variations for each planet. In these multiplanet compact Kepler systems, oscillations of their inclination angles are remarkably hard to excite; as a result, they tend to remain continually mutually transiting (CMT-stable). We study this issue further by augmenting the planet masses and determining the enhancement factor required for oscillations to move the systems out of transit. The oscillations of inclination found here inform the recently suggested dichotomy in the sample of Solar systems observed by Kepler.
DEFF Research Database (Denmark)
Hahn, Thomas; Foldspang, Anders
1997-01-01
Quadriceps muscle contraction tends to straighten the Q angle. We expected that sports comprising a high amount of quadriceps training could be associated with low Q angles. The aim of the present study was to estimate the Q angle in athletes and to investigate its potential associations with par......Quadriceps muscle contraction tends to straighten the Q angle. We expected that sports comprising a high amount of quadriceps training could be associated with low Q angles. The aim of the present study was to estimate the Q angle in athletes and to investigate its potential associations...... with participation in sport. Three hundred and thirty-nine athletes had their Q angle measured. The mean of right-side Q angles was higher than left side, and the mean Q angle was higher in women than in men. The Q angle was positively associated with years of jogging, and negatively with years of soccer, swimming...... and sports participation at all. It is concluded that the use of Q angle measurements is questionable....
Evaluation of blotchy pigments in the anterior chamber angle as a sign of angle closure
Directory of Open Access Journals (Sweden)
Harsha L Rao
2012-01-01
Full Text Available Background: Blotchy pigments in the anterior chamber (AC angle are considered diagnostic of primary angle closure (PAC. But there are no reports either on the prevalence of blotchy pigments in AC angles or the validity of this sign. Aims: To determine the prevalence of blotchy pigments in AC angles and to evaluate their relationship with glaucomatous optic neuropathy (GON in eyes with occludable angles. Setting and Design: Cross-sectional, comparative study. Materials and Methods: Gonioscopy was performed in 1001 eyes of 526 subjects (245 eyes of 148 consecutive, occludable angle subjects and 756 eyes of 378 non-consecutive, open angle subjects, above 35 years of age. Quadrant-wise location of blotchy pigments was documented. Statistical Analysis: Odds of blotchy pigments in occludable angles against that in open angles were evaluated. Relationship of GON with blotchy pigments in occludable angle eyes was evaluated using a multivariate model. Results: Prevalence of blotchy pigments in occludable angles was 28.6% (95% CI, 22.9-34.3 and in open angles was 4.7% (95% CI, 3.2-6.3. Blotchy pigments were more frequently seen in inferior (16% and superior quadrants (15% of occludable angles, and inferior quadrant of open angles (4%. Odds of superior quadrant blotchy pigments in occludable angles were 33 times that in open angles. GON was seen in 107 occludable angle eyes. Blotchy pigments were not significantly associated with GON (odds ratio = 0.5; P = 0.1. Conclusions: Blotchy pigments were seen in 28.6% of occludable angle eyes and 4.7% of open angles eyes. Presence of blotchy pigments in the superior quadrant is more common in occludable angles. Presence of GON in occludable angle eyes was not associated with blotchy pigments.
National facility for small-angle neutron scattering: five years' operating experience. Draft
International Nuclear Information System (INIS)
At the time of this Conference on Neutron Scattering, the ORNL-NSF-DOE National Facility for Small-Angle Neutron Scattering will have been operating routinely in a full-time user mode for nearly five years. The Facility, located at the High Flux Isotope Reactor at ORNL, is part of the National Center for Small-Angle Scattering Research. Operating experience and scientific highlights for the past five years are surveyed
The application of modern surveying technology in mining survey
Institute of Scientific and Technical Information of China (English)
SHI Jin-feng; SONG Wei-dong; ZHANG Ji-chao; ZHANG Dong-mei
2008-01-01
With the unceasing appearance and widespread application of new surveying technology, the present age mining survey has meet huge change. However, lots of problems occurred while using the new techniques since the number of mine is large in China and condition of the mine district is complex, it in some sense influenced the mine exploitation and management of China. Summarized the present situation of new technical application in mining survey, including the advanced instrumentation equipment, the "3S"technology, the information and the network technology and the information fusion technology and so on, and analyzed the problems which exists in the current mining survey, it also provided new ways to present age mining survey from the sustainable development angle.
Caustic graphene plasmons with Kelvin angle
Shi, Xihang; Gao, Fei; Xu, Hongyi; Yang, Zhaoju; Zhang, Baile
2015-01-01
A century-long argument made by Lord Kelvin that all swimming objects have an effective Mach number of 3, corresponding to the Kelvin angle of 19.5 degree for ship waves, has been recently challenged with the conclusion that the Kelvin angle should gradually transit to the Mach angle as the ship velocity increases. Here we show that a similar phenomenon can happen for graphene plasmons. By analyzing the caustic wave pattern of graphene plasmons stimulated by a swift charged particle moving uniformly above graphene, we show that at low velocities of the charged particle, the caustics of graphene plasmons form the Kelvin angle. At large velocities of the particle, the caustics disappear and the effective semi-angle of the wave pattern approaches the Mach angle. Our study introduces caustic wave theory to the field of graphene plasmonics, and reveals a novel physical picture of graphene plasmon excitation during electron energy-loss spectroscopy measurement.
OPTIMIZATION OF TILT ANGLE FOR PHOTOVOLTAIC ARRAY
Ashok Kumar; N.S.Thakur,; Rahul Makade,; Maneesh Kumar Shivhar
2011-01-01
The performance of a solar radiation conversion system is affected by its tilt angle with the horizontal plane, thus photovoltaic array need to be tilted at the correct angle to maximize the performance of the System, This paper deals with the determination of optimum tilt angle for solar PV array in order to maximize incident solar irradiance. The model starts by calculating the monthly averaged daily solar irradiation components (direct, diffuse, ground- eflected) absorbed by the solar PV a...
... the American Academy of Dermatology's "Suntelligence" sun-smart survey. Please answer the following questions to measure your ... how you incorporate it into your life. The survey will take 5 to 7 minutes to complete. ...
Behavior of Tilted Angle Shear Connectors.
Directory of Open Access Journals (Sweden)
Koosha Khorramian
Full Text Available According to recent researches, angle shear connectors are appropriate to transfer longitudinal shear forces across the steel-concrete interface. Angle steel profile has been used in different positions as L-shaped or C-shaped shear connectors. The application of angle shear connectors in tilted positions is of interest in this study. This study investigates the behaviour of tilted-shaped angle shear connectors under monotonic loading using experimental push out tests. Eight push-out specimens are tested to investigate the effects of different angle parameters on the ultimate load capacity of connectors. Two different tilted angles of 112.5 and 135 degrees between the angle leg and steel beam are considered. In addition, angle sizes and lengths are varied. Two different failure modes were observed consisting of concrete crushing-splitting and connector fracture. By increasing the size of connector, the maximum load increased for most cases. In general, the 135 degrees tilted angle shear connectors have a higher strength and stiffness than the 112.5 degrees type.
Pitch angle of galactic spiral arms
International Nuclear Information System (INIS)
One of the key parameters that characterizes spiral arms in disk galaxies is a pitch angle that measures the inclination of a spiral arm to the direction of galactic rotation. The pitch angle differs from galaxy to galaxy, which suggests that the rotation law of galactic disks determines it. In order to investigate the relation between the pitch angle of spiral arms and the shear rate of galactic differential rotation, we perform local N-body simulations of pure stellar disks. We find that the pitch angle increases with the epicycle frequency and decreases with the shear rate and obtain the fitting formula. This dependence is explained by the swing amplification mechanism.
Best Angle to Orient Two Intersecting Lines
Energy Technology Data Exchange (ETDEWEB)
Awwal, A S; Ferguson, S W; Shull, P B
2006-07-25
Fiducials in the form of intersecting straight lines are used to align the target in the final target chamber of the National Ignition Facility of Lawrence Livermore National Laboratory. One of the techniques used to locate these lines is the Hough transform. When two lines intersect at a 90 degree angle, it is tempting to orient the lines to horizontal and vertical directions. There are other possible angles at which the lines may be oriented. One question that arises while designing the fiducials is whether there is a preferred angle or range of angles that leads to higher accuracy. This work attempts to answer this question through detailed computer simulation.
Lateral angle and cranial base sexual dimorphism
DEFF Research Database (Denmark)
Duquesnel Mana, Mathilde; Adalian, Pascal; Lynnerup, Niels
2016-01-01
, to examine sexual dimorphism in the relationship between the lateral angle and cranial base shape. The lateral angle method was tested using a forensic sample of 102 CT scans of the head with known sex. We measured the angle using two methods: measurements directly on the CT slide, the method usually...... major overlap between the female and male shapes. In the light of the observed results, we confirm the lack of accuracy reported when using the lateral angle method to determine sex and we hypothesise that it may be explained by a lack of sexual dimorphism of the cranial base in terms of shape....
The qualitative criterion of transient angle stability
DEFF Research Database (Denmark)
Lyu, R.; Xue, Y.; Xue, F.;
2015-01-01
In almost all the literatures, the qualitative assessment of transient angle stability extracts the angle information of generators based on the swing curve. As the angle (or angle difference) of concern and the threshold value rely strongly on the engineering experience, the validity and robust of...... these criterions are weak. Based on the stability mechanism from the extended equal area criterion (EEAC) theory and combining with abundant simulations of real system, this paper analyzes the criterions in most literatures and finds that the results could be too conservative or too optimistic. It is...
ATLAS, and Wide-Angle Tail Galaxies in ATLAS
Indian Academy of Sciences (India)
Minnie Y. Mao; Rob Sharp; D. J. Saikia; Ray P. Norris; Melanie Johnston-Hollitt; Enno Middelberg; Jim E. J. Lovell
2011-12-01
Using the Australia Telescope Compact Array (ATCA), ATLAS (Australia Telescope Large Area Survey) is imaging two fields totalling 7 square degrees down to 10 Jy beam-1 at 1.4 GHz. We have found 6 wide-angle tail galaxies (WATs), 4 of which have sufficient data to identify associated galaxy overdensities. The largest WAT, at a red-shift of 0.22, appears to be associated with an overdensity of galaxies that is spread over an unusually large extent of 12Mpc, with a velocity range of 4500 km s-1. Here we present the WATs in ATLAS and discuss the implications of these observations for future large-scale radio surveys such as ASKAP-EMU.
Small solid angle device setup and application
International Nuclear Information System (INIS)
To quantize the weight of Uranium-plate accurately, the small solid angle device was redesigned. To fit the requirement of homogeneity check, the sliding base was introduced in the design. This paper presents the detailed application of small solid angle device setup and quantization of Uranium-plate and homogeneity check. (authors)
Constructing euclidean simplex with prescribed dihedral angles
International Nuclear Information System (INIS)
Given 1/2n (n + 1) dihedral angles, what is the condition under which there exists an n-dimensional simplex with the prescribed dihedral angles? A complete solution for this problem is given with application demonstrated. (author). 3 refs
Distribution of angles in hyperbolic lattices
DEFF Research Database (Denmark)
Risager, Morten Skarsholm; Truelsen, Jimi Lee
2010-01-01
We prove an effective equidistribution result about angles in a hyperbolic lattice. We use this to generalize a result from the study by Boca.......We prove an effective equidistribution result about angles in a hyperbolic lattice. We use this to generalize a result from the study by Boca....
Distribution of Angles in Hyperbolic Lattices
DEFF Research Database (Denmark)
S. Risager, Morten; L. Truelsen, Jimi
2008-01-01
We prove an effective equidistribution result about angles in a hyperbolic lattice. We use this to generalize a result due to F. P. Boca.......We prove an effective equidistribution result about angles in a hyperbolic lattice. We use this to generalize a result due to F. P. Boca....
A lattice determination of gA and left angle x right angle from overlap fermions
International Nuclear Information System (INIS)
We present results for the nucleon's axial charge gA and the first moment left angle x right angle of the unpolarized parton distribution function from a simulation of quenched overlap fermions. (orig.)
Impact angle control of interplanetary shock geoeffectiveness: A statistical study
Oliveira, Denny M.; Raeder, Joachim
2015-06-01
We present a survey of interplanetary (IP) shocks using Wind and ACE satellite data from January 1995 to December 2013 to study how IP shock geoeffectiveness is controlled by IP shock impact angles. A shock list covering one and a half solar cycle is compiled. The yearly number of IP shocks is found to correlate well with the monthly sunspot number. We use data from SuperMAG, a large chain with more than 300 geomagnetic stations, to study geoeffectiveness triggered by IP shocks. The SuperMAG SML index, an enhanced version of the familiar AL index, is used in our statistical analysis. The jumps of the SML index triggered by IP shock impacts on the Earth's magnetosphere are investigated in terms of IP shock orientation and speed. We find that, in general, strong (high speed) and almost frontal (small impact angle) shocks are more geoeffective than inclined shocks with low speed. The strongest correlation (correlation coefficient R = 0.78) occurs for fixed IP shock speed and for varied IP shock impact angle. We attribute this result, predicted previously with simulations, to the fact that frontal shocks compress the magnetosphere symmetrically from all sides, which is a favorable condition for the release of magnetic energy stored in the magnetotail, which in turn can produce moderate to strong auroral substorms, which are then observed by ground-based magnetometers.
Impact Angle Control of Interplanetary Shock Geoeffectiveness: A Statistical Study
Oliveira, D M
2015-01-01
We present a survey of interplanetary (IP) shocks using WIND and ACE satellite data from January 1995 to December 2013 to study how IP shock geoeffectiveness is controlled by IP shock impact angles. A shock list covering one and a half solar cycle is compiled. The yearly number of IP shocks is found to correlate well with the monthly sunspot number. We use data from SuperMAG, a large chain with more than 300 geomagnetic stations, to study geoeffectiveness triggered by IP shocks. The SuperMAG SML index, an enhanced version of the familiar AL index, is used in our statistical analysis. The jumps of the SML index triggered by IP shock impacts on the Earth's magnetosphere is investigated in terms of IP shock orientation and speed. We find that, in general, strong (high speed) and almost frontal (small impact angle) shocks are more geoeffective than inclined shocks with low speed. The strongest correlation (correlation coefficient R = 0.70) occurs for fixed IP shock speed and varying the IP shock impact angle. We ...
Apparent Contact Angle and Contact Angle Hysteresis on Liquid Infused Surfaces
Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim
2016-01-01
We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a strong dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small b...
Cherbal, Omar; Maamache, Mustapha; Drir, Mahrez
2003-01-01
We propose to determinate the nonadiabatic Hannay’s angle of spin one half in a varying external magnetic field, by using an averaged version of the variational principal. We also show how the evolution and this nonadiabatic Hannay’s angle is associated with the evolution of Grassmannian invariant-angle coherent states.
Analysis of factors affecting angle ANB.
Hussels, W; Nanda, R S
1984-05-01
Cephalometric analyses based on angular and linear measurements have obvious fallacies, which have been discussed in detail by Moyers and Bookstein. However, the clinical application of such an analysis by the orthodontic profession in treatment planning is widely accepted. Variations of angle ANB are commonly used to determine relative jaw relationships in most of the cephalometric evaluations. Several authors, including points A and B influences angle ANB, as does rotational growth of the upper and lower jaws. In addition, the authors point out that growth in a vertical direction (distance N to B) and an increase of the dental height (distance A to B) may contribute to changes in angle ANB. For a Class I relation (Wits = 0 mm), a mathematical formula has been developed which enables the authors to study the geometric influence of angle ANB caused by the following four effects: (1) rotation of the jaws and/or occlusal plane relative to the anterior cranial base; (2) anteroposterior position of N relative to point B, (3) vertical growth (distance N to B); (4) increase in dental height (distance A to B). It was observed that, contrary to the common belief that an ANB angle of 2 +/- 3.0 degrees is considered normal for a skeletal Class I relation, the calculated values of angle ANB will vary widely with changes in these four controlling factors under the same skeletal Class I conditions (Wits = 0 mm). Therefore, in a case under consideration, angle ANB must be corrected for these geometric effects in order to get a proper perspective of the skeletal discrepancy. This is facilitated by comparing the measured ANB angle with the corresponding ANB angle calculated by a formula for a Class I relationship. The corresponding calculated angle ANB can be taken from the tables which are based upon the formula using the same values for SNB, omega (angle between occlusal plane and anterior cranial base), b (which is distance N to B) and a (dental height measured as perpendicular
Tomlinson, Mark
2010-01-01
An earlier version of this paper was prepared for the joint OECD/Eurostat workshop on innovation surveys, OECD, Paris, June 30th 1999. The paper addresses some issues about the nature of innovation surveys (particularly the new Community Innovation Surveys) and how they might be improved to take on board several crucial developments in contemporary advanced economies. In particular the following topics are discussed: the increased distribution of innovative activity across firm...
Qualitative criterion for atom sputtering angle distributions
International Nuclear Information System (INIS)
A model is introduced to explain the shape of atom polar emission angle distributions for monocomponent targets sputtered by normally incident keV - energy ions. Analytical expressions are obtained from the model which make it possible to identify three known kinds of the angle distributions - subcosinus, isotropic and supracosinus, for given ion energies and target-ion pairs. Furthermore the fourth, hybrid false-isotropic distribution is found, which is superposition of supracosinus and subcosinus distributions. The theoretical predictions of the angle distributions shape agree with the numerical modeling for sputtering of carbon and platinum by 0.1-10 keV Ar+ ions
The Driven Pendulum at Any Drive Angle
VanDalen, G J
2002-01-01
The driven inverted pendulum undergoes stable oscillations if the drive amplitude and frequency are large enough. This classroom demonstration is best used in junior or graduate level Classical Mechanics courses. This paper reintroduces the equation of motion of the driven pendulum, generalizing to arbitrary driving angle. The pendulum will oscillate about a stable angle, other than straight down, if the drive amplitude and frequency are large enough for a given drive angle. We will explore what is meant by ``large enough.'' Emphasis is given to parameters associated with a simply made demonstration apparatus.
Compression failure of angle-ply laminates
Peel, Larry D
1991-01-01
The present work deals with modes and mechanisms of failure in compression of angleply laminates. Experimental results were obtained from 42 angle-ply IM7/8551-7a specimens with a lay-up of [ (±9) / (=F9)] 6s where 9, the off-axis angle, ranged from 0° to 90°. The results showed four failure modes, these modes being a function of off-axis angle. Failure modes include fiber compression, inplane transverse tension, inplane shear, and inplane transverse compression. Excessive inte...
Clark, S E; Peek, J E G; Putman, M E; Babler, B L
2015-01-01
Using high-resolution data from the Galactic Arecibo L-Band Feed Array HI (GALFA-HI) survey, we show that linear structure in Galactic neutral hydrogen (HI) correlates with the magnetic field orientation implied by Planck 353 GHz polarized dust emission. The structure of the neutral interstellar medium is more tightly coupled to the magnetic field than previously known. At high Galactic latitudes, where the Planck data are noise-dominated, the HI data provide an independent constraint on the Galactic magnetic field orientation, and hence the local dust polarization angle. We detect strong cross-correlations between template maps constructed from estimates of dust intensity combined with either HI-derived angles, starlight polarization angles, or Planck 353 GHz angles. The HI data thus provide a new tool in the search for inflationary gravitational wave B-mode polarization in the cosmic microwave background, which is currently limited by dust foreground contamination.
Ducted turbine theory with right angled ducts
International Nuclear Information System (INIS)
This paper describes the use of an inviscid approach to model a ducted turbine – also known as a diffuser augmented turbine – and a comparison of results with a particular one-dimensional theory. The aim of the investigation was to gain a better understanding of the relationship between a real duct and the ideal diffuser, which is a concept that is developed in the theory. A range of right angled ducts, which have a rim for a 90° exit angle, were modelled. As a result, the performance of right angled ducts has been characterised in inviscid flow. It was concluded that right angled ducts cannot match the performance of their associated ideal diffuser and that the optimum rotor loading for these turbines varies with the duct dimensions
The solid angle through the vertical rectangle
Schröer, H.
We want to determine the solid angle through the vertical rectangle. We use the cosine law for sides and the spherical law of sines. The relation to luminous flux (radiant flux or radiant power) is shown.
The solid angle through the isosceles triangle
Schröer, H.
We want to determine the solid angle through the isosceles triangle. We use the cosine law for sides and the spherical law of sines. The relation to luminous flux(radiant flux or radiant power) is shown.
The solid angle through the inclined rectangle
Schröer, H.
We want to determine the solid angle through the inclined rectangle. We use the cosine law for sides and the spherical law of sines. The relation to luminous flux(radiant flux or radiant power) is shown.
Optical fibre angle sensor used in MEMS
International Nuclear Information System (INIS)
There is a need for displacement and angle measurements in many movable MEMS structures. The use of fibre optical sensors helps to measure micrometre displacements and small rotation angles. Advantages of this type of transducers are their simple design, high precision of processing, low costs and ability of a non-contact measurement. The study shows an analysis of a fibre-optic intensity sensor used for MEMS movable structure rotation angle measurement. An intensity of the light in the photodetector is basically dependent on a distance between a reflecting surface and a head surface of the fibre transmitting arm, and the deflection angle. Experimental tests were made for PMMA 980/1000 plastic fibres, ΘNA=33°. The study shows both analytical and practical results. It proves that calculated and experimental characteristics for the analysed transducers are similar.
EMERGENCE ANGLE OF FLOW OVER AN AERATOR
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
Aerator is an important device for release works of hydraulic structures with high-speed flow in order to protect them from cavitation damage. This kind of protecting effect is related closely to cavity length below the aerator, while the cavity length is dominated by the emergence angle over the aerator. Therefore it is crucial to determine this angle accurately. In the present paper the affecting intensities of flow depth and the fluctuating velocity on this angle were analyzed through two introduced parameters. Furthermore, the improved expressions of emergence angle estimation, for both ramp-type and step-type aerators, were presented by means of 68 sets of experimental data from 6 projects based on error theory. The results showed that the present method has higher accuracy than the previously reported methods.
International Nuclear Information System (INIS)
The theoretical and experimental problems appearing in diffraction experiments at very low angles by several kinds of materials are discussed. The importance of synchrotron radiation in such problems is shown. (L.C.)
Schofield, W
2001-01-01
The aim of Engineering Surveying has always been to impart and develop a clear understanding of the basic topics of the subject. The author has fully revised the book to make it the most up-to-date and relevant textbook available on the subject.The book also contains the latest information on trigonometric levelling, total stations and one-person measuring systems. A new chapter on satellites ensures a firm grasp of this vitally important topic.The text covers engineering surveying modules for civil engineering students on degree courses and forms a reference for the engineering surveying module in land surveying courses. It will also prove to be a valuable reference for practitioners.* Simple clear introduction to surveying for engineers* Explains key techniques and methods* Details reading systems and satellite position fixing
Angles between subspaces and their tangents
Zhu, Peizhen; Knyazev, Andrew V.
2012-01-01
Principal angles between subspaces (PABS) (also called canonical angles) serve as a classical tool in mathematics, statistics, and applications, e.g., data mining. Traditionally, PABS are introduced via their cosines. The cosines and sines of PABS are commonly defined using the singular value decomposition. We utilize the same idea for the tangents, i.e., explicitly construct matrices, such that their singular values are equal to the tangents of PABS, using several approaches: orthonormal and...
Flipped Angles and Phases: A Systematic Study
Ellis, J.; Lopez, J; Nanopoulos, D.; Olive, K.
1993-01-01
We discuss systematically the fermion mass and mixing matrices in a generic \\linebreak field-theoretical flipped $SU(5)$ model, with particular applications to neutrino and baryon number-changing physics. We demonstrate that the different quark flavour branching ratios in proton decay are related to the Cabibbo-Kobayashi-Maskawa angles, whereas the lepton flavour branching ratios are undetermined. The light neutrino mixing angles observable via oscillation effects are related to the heavy con...
Primary angle-closure glaucoma: an update.
Wright, Carrie; Tawfik, Mohammed A; Waisbourd, Michael; Katz, Leslie J
2016-05-01
Primary angle-closure glaucoma is potentially a devastating disease, responsible for half of glaucoma-related blindness worldwide. Angle closure is characterized by appositional approximation or contact between the iris and trabecular meshwork. It tends to develop in eyes with shallow anterior chambers, anteriorly positioned or pushed lenses, and angle crowding. Risk of primary angle-closure glaucoma is high among women, the elderly and the hyperopic, and it is most prevalent in Asia. Investigation into genetic mechanisms of glaucoma inheritance is underway. Diagnosis relies on gonioscopy and may be aided by anterior segment optical coherence tomography and ultrasound biomicroscopy. Treatment is designed to control intraocular pressure while monitoring changes to the angle and optic nerve head. Treatment typically begins with medical management through pressure-reducing topical medications. Peripheral iridotomy is often performed to alleviate pupillary block, while laser iridoplasty has been found effective for mechanisms of closure other than pupillary block, such as plateau iris syndrome. Phacoemulsification, with or without goniosynechialysis, both in eyes with existing cataracts and in those with clear lenses, is thus far a viable treatment alternative. Long-term research currently underway will examine its efficacy in cases of angle closure in early stages of the disease. Endoscopic cyclophotocoagulation is another treatment option, which can be combined with cataract surgery. Trabeculectomy remains effective therapy for more advanced cases. PMID:26119516
Viewing angle analysis of integral imaging
Wang, Hong-Xia; Wu, Chun-Hong; Yang, Yang; Zhang, Lan
2007-12-01
Integral imaging (II) is a technique capable of displaying 3D images with continuous parallax in full natural color. It is becoming the most perspective technique in developing next generation three-dimensional TV (3DTV) and visualization field due to its outstanding advantages. However, most of conventional integral images are restricted by its narrow viewing angle. One reason is that the range in which a reconstructed integral image can be displayed with consistent parallax is limited. The other is that the aperture of system is finite. By far many methods , an integral imaging method to enhance the viewing angle of integral images has been proposed. Nevertheless, except Ren's MVW (Maximum Viewing Width) most of these methods involve complex hardware and modifications of optical system, which usually bring other disadvantages and make operation more difficult. At the same time the cost of these systems should be higher. In order to simplify optical systems, this paper systematically analyzes the viewing angle of traditional integral images instead of modified ones. Simultaneously for the sake of cost the research was based on computer generated integral images (CGII). With the analysis result we can know clearly how the viewing angle can be enhanced and how the image overlap or image flipping can be avoided. The result also promotes the development of optical instruments. Based on theoretical analysis, preliminary calculation was done to demonstrate how the other viewing properties which are closely related with the viewing angle, such as viewing distance, viewing zone, lens pitch, and etc. affect the viewing angle.
Ray-tracing studies for a whole-viewing-angle retroreflector
International Nuclear Information System (INIS)
The APS Survey and Alignment team uses LEICA laser trackers for the majority of their alignment tasks. These instruments utilize several different retroreflectors for tracking the path of the laser interferometer. Currently in use are open-air corner cubes with an acceptance angle of ±20 degree, corner cube prisms with an acceptance angle of ±50degree, and a Cat's eye with an acceptance angle of ±60degree. Best measurement results can be achieved by using an open-air corner cube that eliminates the need for the laser beam to travel through a different medium before it returns to the instrument detector. However, the trade off is a small acceptance angle. In order to overcome the limitations of the small acceptance angles, Takatsuji et al. has proposed the creation of a full-viewing-angle retroreflector. Based on the notion that the radius R1 of a common Cat's eye is proportional to R2, one can write: R1 = (n minus 1)R2. In the case that n, the refractive index of glass, equals 2, the radii R1 and R2 are identical, and one can create a solid sphere Cat's eye. This design has the advantages that no adhesives are used to bond the two hemispheres together, misalignments between the hemispheres are not an issue, and most importantly, larger acceptance angles are possible. This paper shows the results of their ray tracing calculations characterizing the geometrical optics
Longitudinal Changes of Angle Configuration in Primary Angle-Closure Suspects
Jiang, Yuzhen; Chang, Dolly S.; Zhu, Haogang; Khawaja, Anthony P.; Aung, Tin; Huang, Shengsong; Chen, Qianyun; Munoz, Beatriz; Grossi, Carlota M.
2015-01-01
Objective To determine longitudinal changes in angle configuration in the eyes of primary angle-closure suspects (PACS) treated by laser peripheral iridotomy (LPI) and in untreated fellow eyes. Design Longitudinal cohort study. Participants Primary angle-closure suspects aged 50 to 70 years were enrolled in a randomized, controlled clinical trial. Methods Each participant was treated by LPI in 1 randomly selected eye, with the fellow eye serving as a control. Angle width was assessed in a masked fashion using gonioscopy and anterior segment optical coherence tomography (AS-OCT) before and at 2 weeks, 6 months, and 18 months after LPI. Main Outcome Measures Angle width in degrees was calculated from Shaffer grades assessed under static gonioscopy. Angle configuration was also evaluated using angle opening distance (AOD250, AOD500, AOD750), trabecular-iris space area (TISA500, TISA750), and angle recess area (ARA) measured in AS-OCT images. Results No significant difference was found in baseline measures of angle configuration between treated and untreated eyes. At 2 weeks after LPI, the drainage angle on gonioscopy widened from a mean of 13.5° at baseline to a mean of 25.7° in treated eyes, which was also confirmed by significant increases in all AS-OCT angle width measures (P<0.001 for all variables). Between 2 weeks and 18 months after LPI, a significant decrease in angle width was observed over time in treated eyes (P<0.001 for all variables), although the change over the first 5.5 months was not statistically significant for angle width measured under gonioscopy (P = 0.18), AOD250 (P = 0.167) and ARA (P = 0.83). In untreated eyes, angle width consistently decreased across all follow-up visits after LPI, with a more rapid longitudinal decrease compared with treated eyes (P values for all variables ≤0.003). The annual rate of change in angle width was equivalent to 1.2°/year (95% confidence interval [CI], 0.8–1.6) in treated eyes and 1.6°/year (95% CI, 1
Bioelectric impedance phase angle in breast carcinoma
Directory of Open Access Journals (Sweden)
Ruchi Tyagi
2014-01-01
Full Text Available Context: Worldwide breast cancer is the most frequently diagnosed life threatening cancer and the leading cause of death in women. Bioelectric impedance analysis (BIA affords an emerging opportunity to assess prognosis because of its ability to non invasively assess cell and plasma membrane structure and function by means of phase angle. Aims: To compare the phase angle between patients of breast cancer and their matched control with the help of BIA. Settings and Design: After taking clearance from ethical committee, a total of 34 female cases of histologically proven infiltrating ductal breast carcinoma were included from the surgery IPD, department of surgery. Equal numbers of the matched controls were recruited from the friends and relatives of cases. Materials and Methods: Bio Electrical Impedance Analyzer (BIA BODY STAT QUAD SCAN 4000 was used to measure resistance (R and reactance (Xc by recording a voltage drop in applied current. Phase angle is the ratio of reactance to resistance and is a measure of cell vitality. Statistical analysis used: Unpaired "t" test was applied. Results: In control group, the phase angle showed a mean of 5.479 whereas in test group, it showed a mean value of 4.726. The P value showed a significant difference (P < 0.0001. The smaller the phase angle values were higher was the tumor, nodes, metastases (TNM staging. The phase angles differed significantly from the healthy age matched control values. Conclusions: This study demonstrated that phase angle is a strong predictor of severity of breast cancer and differed significantly between the two groups.
DEFF Research Database (Denmark)
Markussen, Randi; Gad, Christopher
procedures. Subjectivity is rather regulated and constituted in this practice. The relevant question becomes in what particular ways subjectivity and humanness are performed here? We want to look into this question exploring the agency of surveys, their effects and the politics involved in such a scientific......Christopher Gad. Ph.d. Dept. of Information and Media Studies Randi Markussen. Associate Professor, Dept. of Information and Media Studies. rmark@imv.au.dk Abstract: Surveying humanness -politics of care improvement For various reasons we both were subjected to a specific survey procedure...... carried out in a Danish county in order to improve treatment of people who have suffered from long-term illnesses. The surveys concern not only feed back on how people experience their present and past interaction with the social services and health care system; they also ask people to indicate the state...
High brightness angled cavity quantum cascade lasers
International Nuclear Information System (INIS)
A quantum cascade laser (QCL) with an output power of 203 W is demonstrated in pulsed mode at 283 K with an angled cavity. The device has a ridge width of 300 μm, a cavity length of 5.8 mm, and a tilt angle of 12°. The back facet is high reflection coated, and the front facet is anti-reflection coated. The emitting wavelength is around 4.8 μm. In distinct contrast to a straight cavity broad area QCL, the lateral far field is single lobed with a divergence angle of only 3°. An ultrahigh brightness value of 156 MW cm−2 sr−1 is obtained, which marks the brightest QCL to date
High brightness angled cavity quantum cascade lasers
Energy Technology Data Exchange (ETDEWEB)
Heydari, D.; Bai, Y.; Bandyopadhyay, N.; Slivken, S.; Razeghi, M., E-mail: razeghi@eecs.northwestern.edu [Center for Quantum Devices, Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208 (United States)
2015-03-02
A quantum cascade laser (QCL) with an output power of 203 W is demonstrated in pulsed mode at 283 K with an angled cavity. The device has a ridge width of 300 μm, a cavity length of 5.8 mm, and a tilt angle of 12°. The back facet is high reflection coated, and the front facet is anti-reflection coated. The emitting wavelength is around 4.8 μm. In distinct contrast to a straight cavity broad area QCL, the lateral far field is single lobed with a divergence angle of only 3°. An ultrahigh brightness value of 156 MW cm{sup −2 }sr{sup −1} is obtained, which marks the brightest QCL to date.
A heterodyne interferometer for angle metrology
International Nuclear Information System (INIS)
We have developed a compact, high-resolution, angle measurement instrument based on a heterodyne interferometer. Common-path heterodyne interferometer metrology is used to measure displacements of a reflective target surface. In the interferometer set up, an optical mask is used to sample the laser beam reflecting back from four areas on a target surface. From the relative displacement measurements of the target surface areas, we can simultaneously determine angular rotations around two orthogonal axes in a plane perpendicular to the measurement beam propagation direction. The device is used in a testbed for a tracking telescope system where pitch and yaw angle measurements of a flat mirror are performed. Angle noise measurement of the device shows 0.1 nrad/√(Hz) at 1 Hz, at a working distance of 1 m. The operation range and nonlinearity of the device when used with a flat mirror is approximately ±0.15 mrad, and 3 μrad rms, respectively.
Notes on large angle crossing graphs
Dujmovic, Vida; Morin, Pat; Wolle, Thomas
2009-01-01
A graph G is an a-angle crossing (aAC) graph if every pair of crossing edges in G intersect at an angle of at least a. The concept of right angle crossing (RAC) graphs (a=Pi/2) was recently introduced by Didimo et. al. It was shown that any RAC graph with n vertices has at most 4n-10 edges and that there are infinitely many values of n for which there exists a RAC graph with n vertices and 4n-10 edges. In this paper, we give upper and lower bounds for the number of edges in aAC graphs for all 0 < a < Pi/2.
Precision measurements of the CKM angle gamma
CERN. Geneva
2016-01-01
The level of CP-violation permitted within the Standard Model cannot account for the matter dominated universe in which we live. Within the Standard Model the CKM matrix, which describes the quark couplings, is expected to be unitary. By making precise measurements of the CKM matrix parameters new physics models can be constrained, or with sufficient precision the effects of physics beyond the standard model might become apparent. The CKM angle gamma is the least well known angle of the unitarity triangle. It is the only angle easily accessible at tree-level, and furthermore has almost no theoretical uncertainties. Therefore it provides an invaluable Standard Model benchmark against which other new physics sensitive tests of the CP-violation can be made. I will discuss recent measurements of gamma using the the Run 1 LHCb dataset, which improve our knowledge of this key parameter.
The wave vane - A device to measure the breaker angle
Digital Repository Service at National Institute of Oceanography (India)
Chandramohan, P.; Nayak, B.U.; Anand, N.M.
, ,~ ~ O BEACH c /~ ' ! , THEODOLITE Fig. 4. Definition sketch. 178 P. CHANDRAMOHAN ET AL. angle AOC can be calculated, which would be the wave breaker angle with respect to the coastline. It is assumed that the angle made by the crestline...
Positron Emission Mammography with Multiple Angle Acquisition
International Nuclear Information System (INIS)
Positron emission mammography (PEM) of F-18 fluorodeoxyglucose (FDG) uptake in breast tumors with dedicated detectors typically has been accomplished with two planar detectors in a fixed position with the breast under compression. The potential use of PEM imaging at two detector positions to guide stereotactic breast biopsy has motivated us to use PEM coincidence data acquired at two or more detector positions together in a single image reconstruction. Multiple angle PEM acquisition and iterative image reconstruction were investigated using point source and compressed breast phantom acquisitions with 5, 9, 12 and 15 mm diameter spheres and a simulated tumor:background activity concentration ratio of 6:1. Image reconstruction was performed with an iterative MLEM algorithm that used coincidence events between any two detector pixels on opposed detector heads at each detector position. This present study compared two acquisition protocols: 2 angle acquisition with detector angular positions of -15 and +15 degrees and 11 angle acquisition with detector positions spaced at 3 degree increments over the range -15 to +15 degrees. Three- dimensional image resolution was assessed for the point source acquisitions, and contrast and signal-to-noise metrics were evaluated for the compressed breast phantom with different simulated tumor sizes. Radial and tangential resolutions were similar for the two protocols, while normal resolution was better for the 2 angle acquisition. Analysis is complicated by the asymmetric point spread functions. Signal- to-noise vs. contrast tradeoffs were better for 11 angle acquisition for the smallest visible 9 mm sphere, while tradeoff results were mixed for the larger and more easily visible 12 mm and 15 mm diameter spheres. Additional study is needed to better understand the performance of limited angle tomography for PEM. PEM tomography experiments with complete angular sampling are planned
On Dihedral Angles of a Simplex
Maehara, H.
2013-01-01
For an $n$-simplex, let $\\alpha,\\,\\beta$ denote the maximum, and the minimum dihedral angles of the simplex, respectively. It is proved that the inequality $\\alpha\\le \\arccos(1/n)\\le \\beta$ always holds, and either side equality implies that the $n$-simplex is a regular simplex. Similar inequalities are also given for a star-simplex, which is defined as a simplex that has a vertex (apex) such that the angles between distinct edges incident to the apex are all equal. Further, an explicit formu...
Ship wakes: Kelvin or Mach angle?
Rabaud, Marc; Moisy, Frédéric
2013-05-24
From the analysis of a set of airborne images of ship wakes, we show that the wake angles decrease as U(-1) at large velocities, in a way similar to the Mach cone for supersonic airplanes. This previously unnoticed Mach-like regime is in contradiction with the celebrated Kelvin prediction of a constant angle of 19.47° independent of the ship's speed. We propose here a model, confirmed by numerical simulations, in which the finite size of the disturbance explains this transition between the Kelvin and Mach regimes at a Froude number Fr=U/√[gL]~/=0.5, where L is the hull ship length. PMID:23745883
Angle-Resolved Spectroscopy of Parametric Fluorescence
Hsu, Feng-kuo
2013-01-01
The parametric fluorescence from a nonlinear crystal forms a conical radiation pattern. We measure the angular and spectral distributions of parametric fluorescence in a beta-barium borate crystal pumped by a 405-nm diode laser employing angle-resolved imaging spectroscopy. The experimental angle-resolved spectra and the generation efficiency of parametric down conversion are compared with a plane-wave theoretical analysis. The parametric fluorescence is used as a broadband light source for the calibration of the instrument spectral response function in the wavelength range from 450 to 1000 nm.
Ship wakes: Kelvin or Mach angle?
Rabaud, Marc
2013-01-01
From the analysis of a set of airborne images of ship wakes, we show that the wake angles decrease as $U^{-1}$ at large velocities, in a way similar to the Mach cone for supersonic airplanes. This previously unnoticed Mach-like regime is in contradiction with the celebrated Kelvin prediction of a constant angle of $19.47\\degree$ independent of the ship's speed. We propose here a model, confirmed by numerical simulations, in which the finite size of the disturbance explains this transition between the Kelvin and Mach regimes at a Froude number $Fr = U/\\sqrt{gL} \\simeq 0.5$, where $L$ is the hull ship length.
Clinical tibiofemoral angle in south Indian children
Mathew, S. E.; V. Madhuri
2013-01-01
Objectives The development of tibiofemoral angle in children has shown ethnic variations. However this data is unavailable for our population. Methods We measured the tibiofemoral angle (TFA) and intercondylar and intermalleolar distances in 360 children aged between two and 18 years, dividing them into six interrupted age group intervals: two to three years; five to six years; eight to nine years; 11 to 12 years; 14 to 15 years; and 17 to 18 years. Each age group comprised 30 boys and 30 gir...
A fringe shadow method for measuring flapping angle and torsional angle of a dragonfly wing
Zeng, Lijiang; Matsumoto, Hirokazu; Kawachi, Keiji
1996-05-01
A fringe shadow (FS) method was developed for measuring the flapping angle and torsional angle of a dragonfly wing during beating motion. This new method involves two sets of fringe patterns projected onto the wing from orthogonal directions. The torsional angle is determined using the length of the shadow of the wing chord that is cast by the two sets of fringe patterns. The flapping angle is determined using the shadowgraph of the wing projected by a laser. The advantages of the FS method are its capability (i) to measure the flapping angle and torsional angle of a dragonfly wing simultaneously using only one high-speed camera and (ii) to recognize the spanwise position of a section from the number of fringes, without having to use diffuse marks that are common in current methods. The resolution of the FS method can be changed easily by adjusting the fringe spacing. The measurement results for the torsional angle and flapping angle of a dragonfly wing prove the effectiveness of the FS method in studying the flight performance of dragonflies.
Ischemia detection from morphological QRS angle changes.
Romero, Daniel; Martínez, Juan Pablo; Laguna, Pablo; Pueyo, Esther
2016-07-01
In this paper, an ischemia detector is presented based on the analysis of QRS-derived angles. The detector has been developed by modeling ischemic effects on the QRS angles as a gradual change with a certain transition time and assuming a Laplacian additive modeling error contaminating the angle series. Both standard and non-standard leads were used for analysis. Non-standard leads were obtained by applying the PCA technique over specific lead subsets to represent different potential locations of the ischemic zone. The performance of the proposed detector was tested over a population of 79 patients undergoing percutaneous coronary intervention in one of the major coronary arteries (LAD (n = 25), RCA (n = 16) and LCX (n = 38)). The best detection performance, obtained for standard ECG leads, was achieved in the LAD group with values of sensitivity and specificity of [Formula: see text], [Formula: see text], followed by the RCA group with [Formula: see text], Sp = 94.4 and the LCX group with [Formula: see text], [Formula: see text], notably outperforming detection based on the ST series in all cases, with the same detector structure. The timing of the detected ischemic events ranged from 30 s up to 150 s (mean = 66.8 s) following the start of occlusion. We conclude that changes in the QRS angles can be used to detect acute myocardial ischemia. PMID:27243441
Small Angle Light Scattering by Biological Objects
International Nuclear Information System (INIS)
In this paper the small angle laser radiation scattering by the particles of different shape and size is analyzed. Experimental results and theoretical calculations show that after ejection from bacteriophage DNA forms the scattering medium consisted of quasi-spherical elements with radius of R⁓10λ0. (author)
Association between Bolton discrepancy and Angle malocclusions
Directory of Open Access Journals (Sweden)
Rodrigo Hermont CANÇADO
2015-01-01
Full Text Available This study aimed to assess and compare the overall and anterior ratios of tooth size discrepancies in all Angle malocclusion groups. The following null hypothesis (H0 was tested: no difference between tooth size discrepancies (overall and anterior would be observed among Angle malocclusion groups. The sample comprised of 711 pre-orthodontic treatment study casts of Brazilian patients with a mean age of 17.42 years selected from private practices in Brazil. The casts were divided into 3 groups according to the type of malocclusion: Class I (n = 321, Class II (n = 324, and Class III patients (n = 66. The measurement of the greatest mesiodistal width of the teeth was performed using a centesimal precision digital caliper directly on the study casts, from the distal surface of the left first molar to the distal surface of the right first molar. The overall and anterior ratios between the maxillary and mandibular teeth were evaluated using Bolton’s method. The following statistical tests were applied: chi-square, independent t-test, and one-way ANOVA. Results showed that all Angle malocclusions groups exhibited a ratio compatible with those recommended by Bolton. With respect to the overall and anterior ratios among the malocclusion groups, no statistically significant differences were found. The null hypothesis was accepted because the results showed no differences in the overall and anterior ratios of tooth size discrepancies among different Angle malocclusion groups.
Testing CMB polarization data using position angles
Preece, Michael
2014-01-01
We consider a novel null test for contamination which can be applied to CMB polarization data that involves analysis of the statistics of the polarization position angles. Specifically, we will concentrate on using histograms of the measured position angles to illustrate the idea. Such a test has been used to identify systematics in the NVSS point source catalogue with an amplitude well below the noise level. We explore the statistical properties of polarization angles in CMB maps. If the polarization angle is not correlated between pixels, then the errors follow a simple $\\sqrt{N_{pix}}$ law. However this is typically not the case for CMB maps since these have correlations which result in an increase in the variance since the effective number of independent pixels is reduced. Then we illustrate how certain classes of systematic errors can result in very obvious patterns in these histograms, and thus that these errors could possibly be identified using this method. We discuss how this idea might be applied in...
Status of the CDF small angle spectrometer
International Nuclear Information System (INIS)
During the 1987 Tevatron collider period the CDF small angle spectrometer system was partially installed and elastic scattering events were recorded in a special high-β run. The design and physics goals of this system are described and results from an analysis of the elastic scattering data are discussed
Improved Beam Angle Control with SPV Metrology
International Nuclear Information System (INIS)
A method of real-time monitoring of implant angle for state-of-the-art ion implant doping in integrated circuit manufacturing has been developed using Surface Photo Voltage measurements on conventional monitor wafers. Measurement results are analyzed and compared to other techniques.
Veering triangulations admit strict angle structures
Hodgson, Craig D; Segerman, Henry; Tillmann, Stephan
2010-01-01
Agol recently introduced the concept of a veering taut triangulation, which is a taut triangulation with some extra combinatorial structure. We define the weaker notion of a "veering triangulation" and use it to show that all veering triangulations admit strict angle structures. We also answer a question of Agol, giving an example of a veering taut triangulation that is not layered.
Experimental technique of small angle neutron scattering
International Nuclear Information System (INIS)
The main parts of Small Angle Neutron Scattering (SANS) spectrometer, and their function and different parameters are introduced from experimental aspect. Detailed information is also introduced for SANS spectrometer 'Membrana-2'. Based on practical experiments, the fundamental requirements and working condition for SANS experiments, including sample preparation, detector calibration, standard sample selection and data preliminary process are described. (authors)
Mie scattering near the critical angle
International Nuclear Information System (INIS)
Complex angular momentum theory is applied to the problem of high-frequency critical light scattering by a spherical cavity near the critical angle. The main contributions to the scattering arise from a critical domain close to critical incidence. The results are in good agreement with the exact Mie solution. (author)
SANS-1: Small angle neutron scattering
Heinemann, André; Mühlbauer, Sebastian
2015-01-01
The new small angle scattering instrument SANS-1, jointly operated by the Technische Universität München and GEMS, Helmholtz-Zentrum Geesthacht, has completed commissioning and is in regular user service (Gilles et al., 2006). SANS-1 is located at the end of neutron guide NL4a in the Neutron Guide Hall West.
Small angle neutron scattering in invar alloys
International Nuclear Information System (INIS)
Some results of low angle neutron scattering on 70-30 and 65-35 FeNi alloys are presented showing the existence of chemical small clusters associated with a magnetization inhomogeneity. A noticeable result is the appearance of a pseudo-periodical magnetization static fluctuation in a 65-35 FeNi alloy after irradiation with 2 MeV electrons
DEFF Research Database (Denmark)
Enemark, Stig
2009-01-01
In relation to surveying education there is one big question to be asked: Is the role of the surveyors changing? In a global perspective the answer will be "Yes". There is a big swing that could be entitled "From Measurement to Management". This does not imply that measurement is no longer a...... surveying education there are a range of other challenges to be faced. These relate to the focus on learning to learn; the need for flexible curriculum to deal with constant change; the move towards introducing virtual academy; the demand for creating a quality culture; and the perspective of lifelong...... efficient interaction between education, research, and professional practice....
Raccanelli, Alvise; Bertacca, Daniele; Jeong, Donghui; Neyrinck, Mark C.; Szalay, Alexander S.
2016-01-01
We study the parity-odd part (that we shall call Doppler term) of the linear galaxy two-point correlation function that arises from wide-angle, velocity, Doppler lensing and cosmic acceleration effects. As it is important at low redshift and at large angular separations, the Doppler term is usually neglected in the current generation of galaxy surveys. For future wide-angle galaxy surveys such as Euclid, SPHEREx and SKA, however, we show that the Doppler term must be included. The effect of t...
Institute of Scientific and Technical Information of China (English)
张晓春; 卢平平
2012-01-01
目前不少企业校园招聘结果不尽人意：有的未能如愿以偿地招得到合适的人才;有的招到人才确留不住人才,这些都制约了企业的长远发展。笔者通过企业角度发放问卷,找出了影响校园招聘有效性的主要因素,从而提高校园招聘会的成效,促使校园招聘活动被广大应届生和企业充分利用,提高应届生的签约率和签约质量。%At present, a lot of powerful enterprises have to held on campus recruitment, companies with well- known enterprises launched a fierce competition for talent, recruit reserve outstanding university graduates. The campus into the large enterprise selection and cultivation of excellent graduates is important way. But the campus recruitment is a complex work, cost, time, quality and other aspects of the organization and has a very high de- mand, and many enterprises campus recruitment results unsatisfactory： some could not have got one＇s wish to move to get suitable talents; some to recruit talent is to keep a talented person, all these restrict enterprises long term development. The author through the angle of enterprises issuing questionnaire, find out the impact of cam- pus recruitment valid primary factor, so as to improve the effectiveness of Campus Recruitment Campus recruit- ment campaign, led by the vast number of graduates and enterprises to make full use of, improve graduates sign- ing rate and sign quality.
Van Cauter, Sofie; Bersou, Maxime
2016-01-01
Residents have many questions concerning their training, education, and future, especially in a professional atmosphere that is considered difficult due to increasing financial and political restrictions in the health care system. To objectify this matter, the young radiologist section (YRS) created an online survey.
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
Are Chinese people happy in today’s fast-paced, modern society? What are the sources of their happiness? In today’s rapidly developing economy, is happiness closely related to wealth or not? A recent happiness survey conducted in China gives some answers.
Choroidal physiology and primary angle closure disease.
Zhang, Xiulan; Wang, Wei; Aung, Tin; Jonas, Jost B; Wang, Ningli
2015-01-01
Primary angle closure disease (PACD), prevalent in Asian countries, is generally associated with a shallower anterior chamber, a shorter axial length, thicker lens, hyperopia, and female sex. Other physiologic factors, however, may be important, especially with regard to triggering acute primary angle closure. Thickening of the choroid has been demonstrated in untreated and treated, acute and chronic PACD eyes. Recently, there has been growing interest in studying the role of the choroid in the pathophysiology of PACD. The emergence of new imaging technology such as the enhanced depth imaging mode of spectral-domain optical coherence tomography and swept-source optical coherence tomography has contributed to understanding PACD pathologies. We summarize the functions of the choroid and choroidal changes in the pathogenesis of PACD, and discuss potential future developments. PMID:26164737
Weak mixing angle measurements at hadron colliders
Di Simone, Andrea; The ATLAS collaboration
2015-01-01
The Talk will cover weak mixing angle measurements at hadron colliders ATLAS and CMS in particular. ATLAS has measured the forward-backward asymmetry for the neutral current Drell Yan process in a wide mass range around the Z resonance region using dielectron and dimuon final states with $\\sqrt{s}$ =7 TeV data. For the dielectron channel, the measurement includes electrons detected in the forward calorimeter which extends the covered phase space. The result is then used to extract a measurement of the effective weak mixing angle. Uncertainties from the limited knowledge on the parton distribution functions in the proton constitute a significant part of the uncertainty and a dedicated study is performed to obtain a PDF set describing W and Z data measured previously by ATLAS. Similar studies from CMS will be reported.
The Contact Angle in Inviscid Fluid Mechanics
Indian Academy of Sciences (India)
P N Shankar; R Kidambi
2005-05-01
We show that in general, the specification of a contact angle condition at the contact line in inviscid fluid motions is incompatible with the classical field equations and boundary conditions generally applicable to them. The limited conditions under which such a specification is permissible are derived;however, these include cases where the static meniscus is not flat. In view of this situation, the status of the many `solutions’ in the literature which prescribe a contact angle in potential flows comes into question. We suggest that these solutions which attempt to incorporate a phenomenological, but incompatible, condition are in some, imprecise sense `weak-type solutions’;they satisfy or are likely to satisfy, at least in the limit, the governing equations and boundary conditions everywhere except in the neighbourhood of the contact line. We discuss the implications of the result for the analysis of inviscid flows with free surfaces.
Sparse regularization in limited angle tomography
Frikel, Jürgen
2011-01-01
We investigate the reconstruction problem of limited angle tomography. Such problems arise naturally in applications like digital breast tomosynthesis, dental tomography, electron microscopy etc. Since the acquired tomographic data is highly incomplete, the reconstruction problem is severely ill-posed and the traditional reconstruction methods, such as filtered backprojection (FBP), do not perform well in such situations. To stabilize the reconstruction procedure additional prior knowledge about the unknown object has to be integrated into the reconstruction process. In this work, we propose the use of the sparse regularization technique in combination with curvelets. We argue that this technique gives rise to an edge-preserving reconstruction. Moreover, we show that the dimension of the problem can be significantly reduced in the curvelet domain. To this end, we give a characterization of the kernel of limited angle Radon transform in terms of curvelets and derive a characterization of solutions obtained thr...
Modeling small angle scattering data using FISH
International Nuclear Information System (INIS)
Full text: Small angle neutron scattering (SANS) and small angle x-ray scattering (SAXS) are important techniques for the characterisation of samples on the nanometer scale. From the scattered intensity pattern information about the sample such as particle size distribution, concentration and particle interaction can be determined. Since the experimental data is in reciprocal space and information is needed about real space, modeling of the scattering data to obtain parameters is extremely important and several paradigms are available. The use of computer programs to analyze the data is imperative for a robust description of the sample to be obtained. This presentation gives an overview of the SAS process and describes the data-modeling program FISH, written by R. Heenan 1983-2000. The results of using FISH to obtain the particle size distribution of bubbles in the aluminum hydrogen system and other systems of interest are described. Copyright (2002) Australian X-ray Analytical Association Inc
Dancing droplets: Contact angle, drag, and confinement
Benusiglio, Adrien; Cira, Nate; Prakash, Manu
2015-11-01
When deposited on a clean glass slide, a mixture of water and propylene glycol forms a droplet of given contact angle, when both pure liquids spread. (Cira, Benusiglio, Prakash: Nature, 2015). The droplet is stabilized by a gradient of surface tension due to evaporation that induces a Marangoni flow from the border to the apex of the droplets. The apparent contact angle of the droplets depends on both their composition and the external humidity as captured by simple models. These droplets present remarkable properties such as lack of a large pinning force. We discuss the drag on these droplets as a function of various parameters. We show theoretical and experimental results of how various confinement geometries change the vapor gradient and the dynamics of droplet attraction.
The small angle diffractometer SANS at PSI
Energy Technology Data Exchange (ETDEWEB)
Wagner, W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)
1996-11-01
With the start-up of SINQ an instrument for small angle neutron scattering will be operational which compares well with the world`s largest and most powerful facilities of this kind. Following the classical principle of the D11-instrument of ILL, it is equipped with state-of-the-art components as are nowadays available, including options for further upgrading. Great emphasis was laid upon providing a flexible, universal multi-user facility which guarantees a comfortable and reliable operation. In the present paper, the principle layout of the instrument is presented, and the individual components are described in detail. The paper concludes with model application of small angle scattering to a system of dilute CuCo alloys which undergo a phase separation under thermal treatment, forming spherical Co-precipitates dispersed in a Cu-rich matrix. (author) 3 figs., 1 tab., 14 refs.
Foreign Body Embedded in Anterior Chamber Angle
Shmuel Graffi; Beatrice Tiosano; Ran Ben Cnaan; Jonathan Bahir; Modi Naftali
2012-01-01
Introduction. We present a case of a metallic foreign body embedded in the anterior chamber angle. After standing in close proximity to a construction worker breaking a tile, a 26-year-old woman using soft contact lens for the correction of mild myopia presented to emergency department for evaluation of a foreign body sensation of her right eye. Methods and Results. Diagnosis was confirmed by gonioscopic examination and a noncontrast CT scan of head and orbits. The foreign body was removed by...
Cognitive models for the concept of angle
Matos, José Manuel Leonardo de
1999-01-01
The instructional models taught in class were similar to the students' models. The teachers addressed angle as a basic-level category, discussed its submodels, clarified the boundaries, and established cognitive reference points. They gradually increased the use of complex metaphors and of several models. The study enriched the characterization of the first two levels of van Hiele theory and demonstrated the value of categorization theory in understanding how our comprehension ...
Lorentz angle measurements in silicon detectors
Energy Technology Data Exchange (ETDEWEB)
Bartsch, V.; Boer, W. de E-mail: wim.de.boer@cern.ch; Bol, J.; Dierlamm, A.; Grigoriev, E.; Hauler, F.; Heising, S.; Herz, O.; Jungermann, L.; Keraenen, R.; Koppenhoefer, M.; Roederer, F.; Schneider, T
2002-02-01
In this paper we study the Lorentz angles of both electrons and holes in magnetic fields up to 8 T and temperatures between 77 and 300 K. This is done before and after irradiating a detector with 21 MeV protons up to a fluence of 10{sup 13}/cm{sup 2}, which is equivalent to {approx}2.8x10{sup 13}/cm{sup 2} 1 MeV neutrons.
Low angle resistivity anomaly in layered superconductors
International Nuclear Information System (INIS)
The pinning effect of vortex lines by the layered structure (intrinsic pinning) on resistivity of high-Tc, superconductors in the mixed state is investigated by means of perturbation theory. A sharp drop in the resistivity at small angles for which vortex lines are almost aligned with the ab-planes is shown to occur even in a high-temperature region where the pinning potential is reduced by thermal fluctuations
Angles between subspaces computed in Clifford Algebra
Hitzer, Eckhard
2013-01-01
We first review the definition of the angle between subspaces and how it is computed using matrix algebra. Then we introduce the Grassmann and Clifford algebra description of subspaces. The geometric product of two subspaces yields the full relative angular information in an explicit manner. We explain and interpret the result of the geometric product of subspaces gaining thus full practical access to the relative orientation information.
Studies in small angle scattering techniques
International Nuclear Information System (INIS)
Small angle scattering of neutrons, X-rays and γ-rays are found among the spectroscopic methods developed in the recent years. Although these techniques differ from each other in many respects, e.g. radiation sources and technical equipment needed, their power to resolve physical phenomena and areas of application can be discussed in a general scheme. Selected examples are given illustrating the use of specific technical methods. Jahn-Teller driven structural phase transitions in Rare Earth zircons were studied with neutron scattering as well as small angle γ-ray diffraction. The study of neutron scattering from formations of magnetic domains in the Ising ferromagnet LiTbF4 is a second example. Both these examples represent more than experimental test cases since the theoretical interpretations of the data obtained are discussed as well. As a last example the use of small angle scattering methods for the study of molecular biological samples is discussed. In particular the experimental procedures used in connection with scattering from aqueous solutions of proteins and protein complexes are given. (Auth.)
Moment-angle complexes from simplicial posets
Lu, Zhi
2009-01-01
We extend the construction of moment-angle complexes to simplicial posets by associating a certain T^m-space Z_S to an arbitrary simplicial poset S on m vertices. Face rings Z[S] of simplicial posets generalise those of simplicial complexes, but have much more complicated algebraic structure. Our primary motivation is to study the face rings Z[S] by topological methods. The space Z_S has many important topological properties of the original moment-angle complex Z_K associated to a simplicial complex K. In particular, we prove that the integral cohomology algebra of Z_S is isomorphic to the Tor-algebra of the face ring Z[S]. This leads directly to a generalisation of Hochster's theorem, expressing the algebraic Betti numbers of the ring Z[S] in terms of the homology of full subposets in S. Finally, we estimate the total amount of homology of Z_S from below by proving the toral rank conjecture for the moment-angle complexes Z_S.
Off-Angle Iris Correction Methods
Energy Technology Data Exchange (ETDEWEB)
Santos-Villalobos, Hector J [ORNL; Thompson, Joseph T [ORNL; Karakaya, Mahmut [ORNL; Boehnen, Chris Bensing [ORNL
2016-01-01
In many real world iris recognition systems obtaining consistent frontal images is problematic do to inexperienced or uncooperative users, untrained operators, or distracting environments. As a result many collected images are unusable by modern iris matchers. In this chapter we present four methods for correcting off-angle iris images to appear frontal which makes them compatible with existing iris matchers. The methods include an affine correction, a retraced model of the human eye, measured displacements, and a genetic algorithm optimized correction. The affine correction represents a simple way to create an iris image that appears frontal but it does not account for refractive distortions of the cornea. The other method account for refraction. The retraced model simulates the optical properties of the cornea. The other two methods are data driven. The first uses optical flow to measure the displacements of the iris texture when compared to frontal images of the same subject. The second uses a genetic algorithm to learn a mapping that optimizes the Hamming Distance scores between off-angle and frontal images. In this paper we hypothesize that the biological model presented in our earlier work does not adequately account for all variations in eye anatomy and therefore the two data-driven approaches should yield better performance. Results are presented using the commercial VeriEye matcher that show that the genetic algorithm method clearly improves over prior work and makes iris recognition possible up to 50 degrees off-angle.
Brewster Angle Polarizing Beamsplitter Laser Damage Competition: P polarization
Stolz, Christopher J.; Runkel, Jeff
2012-11-01
Brewster angle plate polarizing beamsplitters play a critical role in splitting and combining beams within high power laser systems. A laser damage competition of polarizer beamsplitter coatings creates the opportunity to survey the current laser resistance these coatings within private industry, governmental institutions, and universities by a direct comparison of samples tested under identical conditions. The requirements of the coatings are a minimum transmission of 95% at "P" polarization and minimum reflection of 99% at "S" polarization at 1064 nm and 56.4 degrees angle of incidence. The choice of coating materials, design, and deposition method were left to the participant. Laser damage testing was performed according to the ISO 11254 standard utilizing a 1064 nm wavelength laser with a 10 ns pulse length operating at a repetition rate of 20 Hz. A double blind test assured sample and submitter anonymity so only a summary of the results are presented. In addition to the laser resistance results, details of cleaning methods, deposition processes, coating materials and layer count, and spectral results are also shared. Because of the large number of samples that were submitted, damage testing was conducted at "P" polarization only with "S" polarization damage testing reserved for next year on these submitted samples. Also the samples were only tested in the forward propagating direction; specifically samples were irradiated from air as the incident medium, through the thin film, and then through the substrate. In summary, a 6:1 difference existed for "P" polarization damage fluences amongst all of the competitors with the dominate variables that impacted the laser resistance being the deposition materials, deposition process, and cleaning method.
Aerodynamic Investigation of Incidence Angle Effects in a Large Scale Transonic Turbine Cascade
McVetta, Ashlie B.; Giel, Paul W.; Welch, Gerard E.
2013-01-01
Aerodynamic measurements showing the effects of large incidence angle variations on an HPT turbine blade set are presented. Measurements were made in NASA's Transonic Turbine Blade Cascade Facility which has been used in previous studies to acquire detailed aerodynamic and heat transfer measurements for CFD code validation. The current study supports the development of variable-speed power turbine (VSPT) speed-change technology for the NASA Large Civil Tilt Rotor (LCTR) vehicle. In order to maintain acceptable main rotor propulsive efficiency, the VSPT operates over a nearly 50 percent speed range from takeoff to altitude cruise. This results in 50deg or more variations in VSPT blade incidence angles. The cascade facility has the ability to operate over a wide range of Reynolds numbers and Mach numbers, but had to be modified in order to accommodate the negative incidence angle variation required by the LCTR VSPT operation. Using existing blade geometry with previously acquired aerodynamic data, the tunnel was re-baselined and the new incidence angle range was exercised. Midspan exit total pressure and flow angle measurements were obtained at seven inlet flow angles. For each inlet angle, data were obtained at five flow conditions with inlet Reynolds numbers varying from 6.83×10(exp 5) to 0.85×10(exp 5) and two isentropic exit Mach numbers of 0.74 and 0.34. The midspan flowfield measurements were acquired using a three-hole pneumatic probe located in a survey plane 8.6 percent axial chord downstream of the blade trailing edge plane and covering three blade passages. Blade and endwall static pressure distributions were also acquired for each flow condition.
Ray-tracing studies for a whole-viewing-angle retro-reflector
International Nuclear Information System (INIS)
The APS Survey and Alignment team uses LEICA laser trackers for the majority of their alignment tasks. These instruments utilize several different retro-reflectors for tracking the path of the laser interferometer. Currently in use are open-air comer cubes with an acceptance angle of ±20 deg C, comer cube prisms with an acceptance angle of ±50 deg C, and a Cat's eye with an acceptance angle of ±60 deg C. Best measurement results can be achieved by using an open-air comer cube that eliminates the need for the laser beam to travel through a different medium before it returns to the instrument detector. However, the trade off is a small acceptance angle. In order to overcome the limitations of the small acceptance angles, Takatsuji et al. have proposed the creation of a full-viewing-angle retro-reflector. Based on the notion that the radius R1 of a common Cat's eye is proportional to R2, one can write: R1= (n-1)R2 In the case that n, the refractive index of glass, equals 2, the radii R1 and R2 are identical, and one can create a solid sphere Cat's eye. This design has the advantages that no adhesives are used to bond the two hemispheres together, misalignments between the hemispheres are not an issue, and most importantly, larger acceptance angles are possible. This paper shows the results of our ray tracing calculations characterizing the geometrical optics. In Section 2 we derived the analytical expressions for choosing the index of refraction n of a glass sphere based on the specifications of the reflected beam. We also provided an approximation for calculating the minimum radius of a reflector sphere based on efficiency considerations. Finally, in section 3, the analytically derived results were confirmed in a design study for a Cat's eye. (authors)
Multiple Surveys of Students and Survey Fatigue
Porter, Stephen R.; Whitcomb, Michael E.; Weitzer, William H.
2004-01-01
This chapter reviews the literature on survey fatigue and summarizes a research project that indicates that administering multiple surveys in one academic year can significantly suppress response rates in later surveys. (Contains 4 tables.)
Perceptions of tilt angles of an agricultural tractor.
Görücü, Serap; Cavallo, Eugenio; Murphy, Dennis
2014-01-01
A tractor stability simulator has been developed to help study tractor operators' perceptions of angles when the simulator is tilted to the side. The simulator is a trailer-mounted tractor cab equipped with hydraulic lift that can tilt the tractor cabin up to 30 degrees. This paper summarizes data from 82 participants who sat in the simulator while it was tilted. Demographic variables, estimates of tilt angles, and measured tilt angles were collected. The effects of age, gender, tractor driving experience, and frequency of operation on the estimated and measured tilt angles were analyzed. The results showed that about 50% of the participants reported estimations of side tilt angles within ±5 degrees of the actual angles, and nearly the same percentage overestimated the actual side tilt angles. Only a small percentage underestimated the angles. Older, more experienced, and male participants set higher limits on the actual angle at which they felt uncomfortable and would not drive. PMID:24417527
Hoare, M G; Churchwell, E B; Diamond, P; Cotton, W D; Chandler, C J; Smethurst, S; Kurtz, S E; Mundy, L G; Dougherty, S M; Fender, R P; Fuller, G A; Jackson, J M; Garrington, S T; Gledhill, T R; Goldsmith, P F; Lumsden, S L; Martí, J; Moore, T J T; Muxlow, T W B; Oudmaijer, R D; Pandian, J D; Paredes, J M; Shepherd, D S; Spencer, R E; Thompson, M A; Umana, G; Urquhart, J S; Zijlstra, A A
2012-01-01
We describe the motivation, design and implementation of the CORNISH survey, an arcsecond resolution radio continuum survey of the inner Galactic plane at 5 GHz using the Karl G. Jansky Very Large Array (VLA). It is a blind survey co-ordinated with the northern Spitzer GLIMPSE I region covering 10 deg < l < 65 deg and |b| < 1 deg at similar resolution. We discuss in detail the strategy that we employed to control the shape of the synthesised beam across this survey that covers a wide range of fairly low declinations. Two snapshots separated by 4 hours in hour angle kept the beam elongation to less that 1.5 over 75% of the survey area and less than 2 over 98% of the survey. The prime scientific motivation is to provide an unbiased survey for ultra-compact HII regions to study this key phase in massive star formation. A sensitivity around 2 mJy will allow the automatic distinction between radio loud and quiet mid-IR sources found in the Spitzer surveys. This survey has many legacy applications beyond s...
Analyzing biomolecular interactions by variable angle ellipsometry
Wu, Jiun-Yan; Lee, Chih-Kung; Lee, J. H.; Shiue, Shuen-Chen; Lee, Shu-Sheng; Lin, Shiming
2001-10-01
In this paper, an innovative ellipsometer is developed and applied to metrology of the biomolecular interaction on a protein biochip. Both the theory, optical and opto-mechanical configurations of this newly developed ellipsometer and methodologies adopted in system design to improve the system performance are presented. It will be shown that by measuring the ellipsometric parameters, the corresponding concentration variation in biochemical reaction can be calculated according to stoichiometry analysis. By applying the variable angle ellipsometry to analysis of a multi-layered sample, the thickness and concentration are resolved. It is believed that the newly developed ellipsometer biosensor is able to undertake an accurate measurement on biomedical interaction.
CDF status report on small angle physics
International Nuclear Information System (INIS)
The 1988-1989 Tevatron Collider run at Fermilab was very fruitfull for CDF. More than 4.5 inverse pbarn were written to tape with a trigger emphasizing hard, short distance interactions. A minor part of the run was devoted to special high - beta runs for the measurement of σtot, σel, dσel/dt and of diffraction dissociation. These measurements are performed in CDF with a double-arm magnetic spectrometer at extremely small angles around the beam pipe and a tracking detector surrounding completely the interaction region. The design and the performance of these systems are described and the quality of data is discussed. (orig.)
Small angles Bhabha scattering: two loop approximation
International Nuclear Information System (INIS)
The elastic and inelastic cross sections for small angles e+e- scattering at high energies are considered. We prove that all the diagrams with two or more virtual photons in scattering channel may be omitted when calculating the radiative corrections with accuracy of the order 0.1%. It is the consequence of the generalized eikonal representation for elastic and inelastic amplitudes. We take into account the processes of single and double bremsstrahlung in the same and opposite directions and the pair production processes. Basing on this calculations we construct the combined formula for the inclusive scattering electron and positron cross section in terms of the structure functions. 15 refs.; 10 figs
Optimum Staging with Varying Thrust Attitude Angle
Directory of Open Access Journals (Sweden)
T. N. Srivastava
1966-07-01
Full Text Available Optimum staging programme for step rockets of arbitrary number of stages having different specific impulses and mass fractions with stages is derived, the optimization criterion being minimum take-off weight for a desired burntout velocity at an assigned altitude. Variation of thrust attitude angle from stage to stage and effects of gravity factor are taken into account. Analysis is performed for a degenerate problem obtained by relaxing the altitude constraint and it has been shown that problems of Weisbord, Subotowicz, Hall & Zambelli and Malina & Summerfield are the particular cases of the degenerate problem.
Euler angles as torsional flat spaces
Trejo-Mandujano, Hector A.
In this work we use general tensor calculus to compare the geodesic equation of motion and Newton's first law for force-free classical systems that are described by an arbitrary number of generalized coordinates in spaces with and without torsion. We choose as objects of study the flat torsional Euler angle metric spaces for rigid rotators. We tested the equivalence of the two motion equations using computational software that allowed algebraic manipulation. The main result is that the equivalence only holds for torsion-free spaces, and for isotropic force-free rotators. We present analytical calculations for the isotropic case and computational results for the general case.
Embedability between right-angled Artin groups
Kim, Sang-hyun
2011-01-01
In this article we study the right-angled Artin subgroups of a given right-angled Artin group. Starting with a graph $\\gam$, we produce a new graph through a purely combinatorial procedure, and call it the extension graph $\\gam^e$ of $\\gam$. We produce a second graph $\\gam^e_k$, the clique graph of $\\gam^e$, by adding extra vertices for each complete subgraph of $\\gam^e$. We prove that each finite induced subgraph $\\Lambda$ of $\\gam^e$ gives rise to an inclusion $A(\\Lambda)\\to A(\\gam)$. Conversely, we show that if there is an inclusion $A(\\Lambda)\\to A(\\gam)$ then $\\Lambda$ is an induced subgraph of $\\gam^e_k$. These results have a number of corollaries. Let $P_4$ denote the path on four vertices and let $C_n$ denote a cycle of length $n$. We prove that $A(P_4)$ embeds in $A(\\gam)$ if and only if $P_4$ is an induced subgraph of $\\gam$. We prove that if $F$ is any finite forest then $A(F)$ embeds in $A(P_4)$. We recover the first author's result on co--contraction of graphs and prove that if $\\gam$ has no tria...
Diphotons, New Vacuum Angles, and Strong CP
Draper, Patrick
2016-01-01
The Standard Model contains a well-understood, natural, spin-0 diphoton resonance: the $\\pi^0$. Numerous studies have pointed out that the hint of a new diphoton resonance at 750 GeV could be a pion analog, identified with the pseudo-Nambu-Goldstone boson of a chiral symmetry spontaneously broken by new strong dynamics at the TeV scale. These "hypercolor" models are generically expected to violate parity through a topological angle $\\tilde\\theta$. We discuss the physics of $\\tilde\\theta$ and its impact on the phenomenology of the new sector. We also describe some of the theoretical implications of a nonzero $\\tilde\\theta$. In particular, $\\tilde\\theta$ can generate an ${\\cal O}(1)$ threshold correction to the QCD vacuum angle $\\theta$ near the TeV scale, sharply constraining ultraviolet solutions to the strong CP problem. Alternatively, finding that $\\tilde\\theta$ is small may be interpreted as evidence in favor of UV solutions to strong CP, particularly those based on spontaneously broken P or CP symmetries.
Active limited-angle tomographic phase microscope
Kuś, Arkadiusz; Krauze, Wojciech; Kujawińska, Małgorzata
2015-11-01
We demonstrate an active, holographic tomography system, working with limited angle of projections, realized by optical-only, diffraction-based beam steering. The system created for this purpose is a Mach-Zehnder interferometer modified to serve as a digital holographic microscope with a high numerical aperture illumination module and a spatial light modulator (SLM). Such a solution is fast and robust. Apart from providing an elegant solution to viewing angle shifting, it also adds new capabilities of the holographic microscope system. SLM, being an active optical element, allows wavefront correction in order to improve measurement accuracy. Integrated phase data captured with different illumination scenarios within a highly limited angular range are processed by a new tomographic reconstruction algorithm based on the compressed sensing technique: total variation minimization, which is applied here to reconstruct nonpiecewise constant samples. Finally, the accuracy of full measurement and the proposed processing path is tested for a calibrated three-dimensional micro-object as well as a biological object-C2C12 myoblast cell.
Hidden topological angles and Lefschetz thimbles
Behtash, Alireza; Schaefer, Thomas; Unsal, Mithat
2015-01-01
We demonstrate the existence of hidden topological angles (HTAs) in a large class of quantum field theories and quantum mechanical systems. HTAs are distinct from theta-parameters in the lagrangian. They arise as invariant angle associated with saddle points of the complexified path integral and their descent manifolds (Lefschetz thimbles). Physical effects of HTAs become most transparent upon analytic continuation in $n_f$ to non-integer number of flavors, reducing in the integer $n_f$ limit to a $\\mathbb Z_2$ valued phase difference between dominant saddles. In ${\\cal N}=1$ super Yang-Mills theory we demonstrate the microscopic mechanism for the vanishing of the gluon condensate. The same effect leads to an anomalously small condensate in a QCD-like $SU(N)$ gauge theory with fermions in the two-index representation. The basic phenomenon is that, contrary to folklore, the gluon condensate can receive both positive and negative contributions in a semi-classical expansion. In quantum mechanics, a HTA leads to ...
Cluster headache or narrow angle glaucoma?
Directory of Open Access Journals (Sweden)
Prasad Palimar
1991-01-01
Full Text Available A 47 year old man with episodes of attacks of pain, redness and mild blurring of vision was investigated for narrow angle glaucoma in view of shallow anterior chambers and a cupped optic disc. The history was reviewed following a spontaneous attack in hospital, which had features other than acute glaucoma. A diagnosis of cluster headache was made on the basis of tests. Cluster headache has been defined as unilateral intense pain, involving the eye and head on one side, usually associated with flushing, nasal congestion and lacrimation; the attacks recurring one or more times daily and lasting 20 - 120 minutes. Such attacks commonly continue for weeks or months and are separated by an asymptomatic period of months to years. This episodic nature, together with unilaterality and tendency to occur at night, closely mimics narrow angle glaucoma. Further, if patients have shallow anterior chambers and disc cupping, the differentiation becomes more difficult yet critical. Resource to provocative tests is often the only answer as the following case report demonstrates.
Contact angles of liquid metals on quasicrystals
International Nuclear Information System (INIS)
Wetting with μm-sized Pb droplets on thin polycrystalline films of decagonal Al13Co4 is reported. The films were prepared under high vacuum conditions in order to have Pb droplets lying on a clean surface. The method used is sequential deposition and annealing of specific stackings of Al and Co layers of nanometric thicknesses. A 300 nm thick Pb slab was then deposited on top of the films and dewetting experiments were followed in situ in a scanning Auger microprobe. The contact angle between the Pb droplet and the surface of the film is measured to be 49 deg. ± 7 deg. Further investigation performed by cross section transmission electron microscopy allows us to better characterize the interface. Taking into account the rugosity of the film, it is concluded that there is partial wetting of the film, which corresponds to a smaller contact angle. The comparison with other results obtained either with pure metals or with a cubic AlCo compound leads to the conclusion that the wetting behaviour of Pb on the surface of a decagonal compound is close to that of a metal with a high melting point and not significantly different from that of a crystalline compound with a small unit cell
Diphotons, new vacuum angles, and strong CP
Draper, Patrick; McKeen, David
2016-04-01
The Standard Model contains a well-understood, natural, spin-0 diphoton resonance: the π 0. Numerous studies have pointed out that the hint of a new diphoton resonance at 750 GeV could be a pion analog, identified with the pseudo-Nambu-Goldstone boson of a chiral symmetry spontaneously broken by new strong dynamics at the TeV scale. These "hypercolor" models are generically expected to violate parity through a topological angle tilde{θ} . We discuss the physics of tilde{θ} and its impact on the phenomenology of the new sector. We also describe some of the theoretical implications of a nonzero tilde{θ} . In particular, tilde{θ} can generate an O(1) threshold correction to the QCD vacuum angle θ near the TeV scale, sharply constraining ultraviolet solutions to the strong CP problem. Alternatively, finding that tilde{θ} is small may be interpreted as evidence in favor of UV solutions to strong CP, particularly those based on spontaneously broken P or CP symmetries.
Alternative IR geometries for TESLA with a small crossing angle
Appleby, R.; Angal-Kalinin, D; Bambade, P.; Mouton, B.; Napoly, O.; Payet, J.; Collaboration, the TESLA
2004-01-01
The formulation of hybrid crossing angle schemes has been a recent development of the TESLA collision geometry debate. Here we report on two such schemes, characterised by either a small vertical or horizontal beam crossing angle.
Lateral angle: a method for sexing using the petrous bone
DEFF Research Database (Denmark)
Norén, Anna; Lynnerup, Niels; Czarnetzki, Alfred;
2005-01-01
very fragmented skeletal remains or cremated bones, where the petrous bone may still be readily recognizable. The method was tested using a forensic sample of 113 petrous bones with known sex. Intra- and interobserver testing was also performed. We found a statistically significant difference in angle......We report on the results of applying the so-called lateral angle method for sex determination on skeletal remains. The lateral angle denotes the angle of the internal auditory canal in relation to the medial surface of the petrous part of the temporal bone. The method involves making a small cast...... size between males and females (mean angle size of males, 39.3 degrees ; mean angle size of females, 48.2 degrees ; P < 0.001). There was no bilateral difference in angle size. In blind trials, 83.2% of petrous bones were assigned to the correct sex. We also tested the lateral angle method against an...
Note on Four Dp-Branes at Angles
Vancea, I V
2001-01-01
In this note we analyse the potential of a system of four Dp-branes at arbitrary angles. The equilibrium configurations for various values of the relative angles and distances among branes are discussed.
Group of Eight (NJ1), 2012
2012-01-01
In 2011, the Group of Eight (Go8) conducted a survey on the state of its buildings and infrastructure. The survey is the third Go8 Infrastructure survey, with previous surveys being conducted in 2007 and 2009. The current survey updated some of the information collected in the previous surveys. It also collated data related to aspects of the…
Modified Wide-angle Beam Propagation Method Using Douglas Operators①
Institute of Scientific and Technical Information of China (English)
无
1997-01-01
A modified wide-angle beam propagation based on the Douglas operators is presented .The truncation error in the modified wide-angle beam propagation is reduced to o(△x)4in the transverse direction nearly without any increase of the computation time,whereas the error in the ordinary wide-angle beam propagation method is typically o(△x)2.With trivial programming changes,the accuracy is higher,especially in wide-angle propagation.
Range-Angle-Dependent Beamforming by Frequency Diverse Array Antenna
Wen-Qin Wang; Huaizong Shao; Jingye Cai
2012-01-01
This paper proposes a range-angle-dependent beamforming for frequency diverse array (FDA) antenna systems. Unlike conventional phased-array antenna, the FDA antenna employs a small amount of frequency increment compared to the carrier frequency across the array elements. The use of frequency increment generates an antenna pattern that is a function of range, time and angle. The range-angle-dependent beamforming allows the FDA antenna to transmit energy over a desired range or angle. This prov...
Hybrid algorithm for rotor angle security assessment in power systems
D. Prasad Wadduwage; Udaya D. Annakkage; Christine Qiong Wu
2015-01-01
Transient rotor angle stability assessment and oscillatory rotor angle stability assessment subsequent to a contingency are integral components of dynamic security assessment (DSA) in power systems. This study proposes a hybrid algorithm to determine whether the post-fault power system is secure due to both transient rotor angle stability and oscillatory rotor angle stability subsequent to a set of known contingencies. The hybrid algorithm first uses a new security measure developed based on ...
International Nuclear Information System (INIS)
Many, thanks to the hundreds of people who took the time to reply to the CERN Courier readership survey questionnaire published in our May issue. Bringing out a monthly journal is a lonely business. Issue after issue goes out, and the only response is when there's an occasional factual error. Send out a readership survey and a faint echo comes back. Most striking was the sheer enthusiasm of the replies. Despite the current erosion of support in the US (see page 2), subatomic physics has significant world-wide box-office appeal. Most important was to find out who our readers are. 61% of the replies came from Europe, 21% from the USA, 14% from elsewhere, (including the former Soviet Union), and 4% from inside CERN. Not surprisingly, the main audience (37%) is in the high energy physics sector. Then comes teaching (31%), followed closely by accelerators operations and design (12%) and industry (11%). Apart from detailed breakdowns of readership and feedback on the journal's content and style, the replies revealed several major features. Firstly, the CERN Courier is widely read and appreciated. There are a lot of people outside the immediate research field who want to keep broadly up to date with the latest developments in high energy physics and related fields, without getting too involved in details. It was gratifying to receive replies from far-flung places (Nepal, Indonesia,....), and learn how much distant readers appreciate getting such regular information. 'It helps us feel part of the world scene,' was a typical such reply, from Australia. Despite jet airplanes, fax and electronic mail, our planet is still big
Progress in the development of critical-angle transmission gratings
Heilmann, Ralf K.; Bruccoleri, Alex R.; Mukherjee, Pran; Schattenburg, Mark L.
2012-09-01
Recently developed Critical-Angle Transmission (CAT) grating technology - in combination with x-ray CCD cameras and large collecting-area focusing optics - will enable a new generation of soft x-ray spectrometers with unprecedented resolving power and effective area and with at least an order of magnitude improvement in figures-of-merit for emission and absorption line detection. This technology will be essential to address a number of high-priority questions identified in the Astro2010 Decadal Survey “New Worlds New Horizons” and open the door to a new discovery space. CAT gratings combine the advantages of soft x-ray transmission gratings (low mass, relaxed figure and alignment tolerances, transparent at high energies) and blazed reflection gratings (high broad band diffraction efficiency, utilization of higher diffraction orders to increase resolving power). We report on progress in the fabrication of large-area (31× 31 mm2) free-standing gratings with two levels of low-blockage support structures using highly anisotropic deep reactive-ion etching.
Optimal Angle Reduction - A Behavioral Approach to Linear System Approximation
Roorda, B.; Weiland, S.
2000-01-01
We investigate the problem of optimal state reduction under minimization of the angle between system behaviors. The angle is defined in a worst-case sense, as the largest angle that can occur between a system trajectory and its optimal approximation in the reduced order model. This problem is analys
Surgery for an "Acute Erection Angle," When Counseling Fails
Nugteren, Helena M.; Pascal, Astrid L.; Schultz, Willibrord C. M. Weijmar; van Driel, Mels F.
2010-01-01
Introduction. During erection, the penis increases in volume, rigidity, and angle. Textbooks of urology and sexology provide only very limited information about erection angle dysfunction. In some men, this angle is too tight toward their belly, causing problems with intercourse. Aim. We reported tw
International Nuclear Information System (INIS)
In this paper, superwide-angle acoustic propagations above the critical angles of the Snell law in liquid—solid superlattice are investigated. Incident waves above the critical angles of the Snell law usually inevitably induce total reflection. However, incident waves with big oblique angles through the liquid—solid superlattice will produce a superwide angle transmission in a certain frequency range so that total reflection does not occur. Together with the simulation by finite element analysis, theoretical analysis by using transfer matrix method suggests the Bragg scattering of the Lamb waves as the physical mechanism of acoustic wave super-propagation far beyond the critical angle. Incident angle, filling fraction, and material thickness have significant influences on propagation. Superwide-angle propagation phenomenon may have potential applications in nondestructive evaluation of layered structures and controlling of energy flux. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
On large angle multiple gluon radiation
Dokshitzer, Y L; Dokshitzer, Yu.L.
2003-01-01
Jet shape observables which involve measurements restricted to a part of phase space are sensitive to multiplication of soft gluon with large relative angles and give rise to specific single logarithmically enhanced (SL) terms (non-global logs). We consider associated distributions in two variables which combine measurement of a jet shape V in the whole phase space (global) and that of the transverse energy flow away from the jet direction, Eout (non-global). We show that associated distributions factorize into the global distribution in V and a factor that takes into account SL contributions from multi-gluon ``hedgehog'' configurations in all orders. The latter is the same that describes the single-variable Eout distribution, but evaluated at a rescaled energy VQ.
Angle-resolved cathodoluminescence imaging polarimetry
Osorio, Clara I; Brenny, Benjamin; Polman, Albert; Koenderink, A Femius
2015-01-01
Cathodoluminescence spectroscopy (CL) allows characterizing light emission in bulk and nanostructured materials and is a key tool in fields ranging from materials science to nanophotonics. Previously, CL measurements focused on the spectral content and angular distribution of emission, while the polarization was not fully determined. Here we demonstrate a technique to access the full polarization state of the cathodoluminescence emission, that is the Stokes parameters as a function of the emission angle. Using this technique, we measure the emission of metallic bullseye nanostructures and show that the handedness of the structure as well as nanoscale changes in excitation position induce large changes in polarization ellipticity and helicity. Furthermore, by exploiting the ability of polarimetry to distinguish polarized from unpolarized light, we quantify the contributions of different types of coherent and incoherent radiation to the emission of a gold surface, silicon and gallium arsenide bulk semiconductor...
Small angle electron diffraction and deflection
Directory of Open Access Journals (Sweden)
T. Koyama
2012-03-01
Full Text Available Electron optical system is constructed in order to obtain small angle diffraction and Lorentz deflection of electrons at the order of down to 10-6 radian in the reciprocal space. Long-distance camera length up to 3000 m is achieved in a conventional transmission electron microscope with LaB6 thermal emission type. The diffraction pattern at 5 × 10-6 radian is presented in a carbon replica grating with 500 nm lattice spacing while the magnetic deflection pattern at 2 × 10-5 radian is exhibited in Permalloy elements. A simultaneous recording of electron diffraction and Lorentz deflection is also demonstrated in 180 degree striped magnetic domains of La0.825Sr0.175MnO3.
Wide-angle energy-momentum spectroscopy
Dodson, Christopher M; Li, Dongfang; Zia, Rashid
2014-01-01
Light emission is defined by its distribution in energy, momentum, and polarization. Here, we demonstrate a method that resolves these distributions by means of wide-angle energy-momentum spectroscopy. Specifically, we image the back focal plane of a microscope objective through a Wollaston prism to obtain polarized Fourier-space momentum distributions, and disperse these two-dimensional radiation patterns through an imaging spectrograph without an entrance slit. The resulting measurements represent a convolution of individual radiation patterns at adjacent wavelengths, which can be readily deconvolved using any well-defined basis for light emission. As an illustrative example, we use this technique with the multipole basis to quantify the intrinsic emission rates for electric and magnetic dipole transitions in europium-doped yttrium oxide (Eu$^{3+}$:Y$_{2}$O$_{3}$) and chromium-doped magnesium oxide (Cr$^{3+}$:MgO). Once extracted, these rates allow us to reconstruct the full, polarized, two-dimensional radi...
Foreign Body Embedded in Anterior Chamber Angle
Directory of Open Access Journals (Sweden)
Shmuel Graffi
2012-01-01
Full Text Available Introduction. We present a case of a metallic foreign body embedded in the anterior chamber angle. After standing in close proximity to a construction worker breaking a tile, a 26-year-old woman using soft contact lens for the correction of mild myopia presented to emergency department for evaluation of a foreign body sensation of her right eye. Methods and Results. Diagnosis was confirmed by gonioscopic examination and a noncontrast CT scan of head and orbits. The foreign body was removed by an external approach without utilizing a magnet. The patient's final outcome was favorable. Discussion. The above is a rare clinical situation, which is impossible to detect on slit-lamp examination without a gonioscopic view. Proper imaging and a specific management are mandatory in order to achieve favorable outcome.
Small-angle scattering in materials science
International Nuclear Information System (INIS)
Small-angle scattering (SAS) of X-rays (SAXS) or neutrons (SANS) are a powerful tools to investigate inhomogeneities in the size range from ∼ 1 nm to ∼ 100 nm. Typical examples in materials science are pores, precipitates in metal alloys or nano-particles in composites. Frequently, these inhomogeneities are not spherical and their alignment is not random, quite in contrast to many other applications of SAS. This requires the use of pinhole geometry and area detectors for the experimental set-up. The present paper focuses on evaluation techniques of two-dimensional (2D) SAS-patterns from some materials investigated by the authors, i.e. metal alloys, carbon composites, wood and bone. Although the examples shown are derived exclusively from SAXS measurements, most of them could stem from SANS measurements as well. (author)
Angle-independent structural colors of silicon
DEFF Research Database (Denmark)
Højlund-Nielsen, Emil; Weirich, Johannes; Nørregaard, Jesper;
2014-01-01
Structural colors are optical phenomena of physical origin, where microscale and nanoscale structures determine the reflected spectrum of light. Artificial structural colors have been realized within recent years. However, multilayer structures require substantial fabrication. Instead we considered...... one-layer surface textures of silicon.We explored four patterns of square structures in a square lattice with periods of 500, 400, 300, and 200 nm. The reflectivity and daylight-colors were measured and compared with simulations based on rigorously coupledwave analysis with excellent agreement. Based...... on the 200-nm periodic pattern, it was found that angle-independent specular colors up to 60 deg of incidence may be provided. The underlying mechanisms include (1) the suppression of diffraction and (2) a strong coupling of light to localized surface states. The strong coupling yields absorption...
Angle-resolved photoemission extended fine structure
International Nuclear Information System (INIS)
Measurements of the Angle-Resolved Photoemission Extended Fine Structure (ARPEFS) from the S(1s) core level of a c(2 x 2)S/Ni(001) are analyzed to determine the spacing between the S overlayer and the first and second Ni layers. ARPEFS is a type of photoelectron diffraction measurement in which the photoelectron kinetic energy is swept typically from 100 to 600 eV. By using this wide range of intermediate energies we add high precision and theoretical simplification to the advantages of the photoelectron diffraction technique for determining surface structures. We report developments in the theory of photoelectron scattering in the intermediate energy range, measurement of the experimental photoemission spectra, their reduction to ARPEFS, and the surface structure determination from the ARPEFS by combined Fourier and multiple-scattering analyses. 202 refs., 67 figs., 2 tabs
Narrow-angle astrometry with PRIMA
Sahlmann, J; Mérand, A; Zimmerman, N; Abuter, R; Chazelas, B; Delplancke, F; Henning, T; Kaminski, A; Köhler, R; Launhardt, R; Mohler, M; Pepe, F; Queloz, D; Quirrenbach, A; Reffert, S; Schmid, C; Schuhler, N; Schulze-Hartung, T
2012-01-01
The Extrasolar Planet Search with PRIMA project (ESPRI) aims at characterising and detecting extrasolar planets by measuring the host star's reflex motion using the narrow-angle astrometry capability of the PRIMA facility at the Very Large Telescope Interferometer. A first functional demonstration of the astrometric mode was achieved in early 2011. This marked the start of the astrometric commissioning phase with the purpose of characterising the instrument's performance, which ultimately has to be sufficient for exoplanet detection. We show results obtained from the observation of bright visual binary stars, which serve as test objects to determine the instrument's astrometric precision, its accuracy, and the plate scale. Finally, we report on the current status of the ESPRI project, in view of starting its scientific programme.
Alsubai, K A; Bramich, D M; Horne, K; Cameron, A Collier; West, R G; Sorensen, P M; Pollacco, D; Smith, J C; Fors, O
2014-01-01
The Qatar Exoplanet Survey (QES) is discovering hot Jupiters and aims to discover hot Saturns and hot Neptunes that transit in front of relatively bright host stars. QES currently operates a robotic wide-angle camera system to identify promising transiting exoplanet candidates among which are the confirmed exoplanets Qatar 1b and 2b. This paper describes the first generation QES instrument, observing strategy, data reduction techniques, and follow-up procedures. The QES cameras in New Mexico complement the SuperWASP cameras in the Canary Islands and South Africa, and we have developed tools to enable the QES images and light curves to be archived and analysed using the same methods developed for the SuperWASP datasets. With its larger aperture, finer pixel scale, and comparable field of view, and with plans to deploy similar systems at two further sites, the QES, in collaboration with SuperWASP, should help to speed the discovery of smaller radius planets transiting bright stars in northern skies.
Spondylolysis and the sacro-horizontal angle in athletes
International Nuclear Information System (INIS)
The frequency of spondylolysis and the relationship between spondylolysis and the sacro-horizontal angle in 143 athletes and 30 non-athletes is reported. Athletes had a larger sacro-horizontal angle than non-athletes. The sacro-horizontal angle was larger in athletes with spondylolysis as compared with those without. An increased incidence of spondylolysis with an increased angle was demonstrated. It is suggested that an increased sacro-horizontal angle may predispose to spondylolysis, especially in combination with the high mechanical loads sustained in certain sports. (orig.)
Temperature Influence on Divergence Angles of Quartz Crystal Wollaston Prism
International Nuclear Information System (INIS)
We propose a structural angle and main refractive indices as two key factors to understand the temperature influence on the divergence angles of the Wollaston prism. The temperature influence on the divergence angles of quartz crystal Wollaston prism is studied theoretically The results show that divergence angles decrease with increasing temperature, while the divergence angle of e-light decrease more quickly than that of o-light. The testing system is established to verify the above results, and the experimental results are in agreement well with the theoretical analysis. (fundamental areas of phenomenology (including applications))
Absolute small-angle measurement based on optical feedback interferometry
Institute of Scientific and Technical Information of China (English)
Jingang Zhong; Xianhua Zhang; Zhixiang Ju
2008-01-01
We present a simple but effective method for small-angle measurement based on optical feedback inter-ferometry (or laser self-mixing interferometry). The absolute zero angle can be defined at the biggest fringe amplitude point, so this method can also achieve absolute angle measurement. In order to verify the method, we construct an angle measurement system. The Fourier-transform method is used to analysis the interference signal. Rotation angles are experimentally measured with a resolution of 10-6 rad and a measurement range of approximately from -0.0007 to +0.0007 rad.
Surveying problem solution with theory and objective type questions
Chandra, AM
2005-01-01
The book provides a lucid and step-by-step treatment of the various principles and methods for solving problems in land surveying. Each chapter starts with basic concepts and definitions, then solution of typical field problems and ends with objective type questions. The book explains errors in survey measurements and their propagation. Survey measurements are detailed next. These include horizontal and vertical distance, slope, elevation, angle, and direction. Measurement using stadia tacheometry and EDM are then highlighted, followed by various types of levelling problems. Traversing is then explained, followed by a detailed discussion on adjustment of survey observations and then triangulation and trilateration.
Impacts of tropical cyclone inflow angle on ocean surface waves
Institute of Scientific and Technical Information of China (English)
ZHAO Wei; HONG Xin
2011-01-01
The inflow angle of tropical cyclones (TC) is generally neglected in numerical studies of ocean surface waves induced by TC. In this study, the impacts of TC inflow angle on ocean surface waves were investigated using a high-resolution wave model. Six numerical experiments were conducted to examine, in detail, the effects of inflow angle on mean wave parameters and the spectrum of wave directions. A comparison of the waves simulated in these experiments shows that inflow angle significantly modifies TC-induced ocean surface waves. As the inflow angle increases, the asymmetric axis of the significant wave height (SWH) field shifts 30° clockwise, and the maximum SWH moves from the front-right to the rear-right quadrant. Inflow angle also affects other mean wave parameters, especially in the rear-left quadrant, such as the mean wave direction, the mean wavelength, and the peak direction. Inflow angle is a key factor in wave models for the reproduction of double-peak or multi-peak patterns in the spectrum of wave directions. Sensitivity experiments also show that the simulation with a 40° inflow angle is the closest to that of the NOAA statistical SLOSH inflow angle. This suggests that 40° can be used as the inflow angle in future TC-induced ocean surface wave simulations when SLOSH or observed inflow angles are not available.
International Nuclear Information System (INIS)
Literature was searched for methods of removing uranium from drinking water. No relevant papers were found, but approximately 1000 publications were identified in a less specific search for methods of removing uranium from water. Most of the latter publications dealt with the recovery of uranium from ores, industrial and analytical chemistry solutions, or seawater. The conditions under which these studies were performed were usually quite different from those normally occurring in municipal water treatment practice, but some potentially interesting systems of recovery were identified. A few papers addressed the problem of removing uranium from natural fresh waters and established the effectiveness of using adsorbents or coprecipitants, such as aluminum hydroxide, ferric hydroxide, activated carbon, and ion exchangers, under certain conditions. Also, many US manufacturers and users of water treatment equipment and products were contacted regarding recommended methods of removing uranium from potable water. Based on the results of these surveys, it is recommended that untreated, partially treated, and finished water samples from municipal water treatment facilities be analyzed to determine their extent of removal of uranium by presently used procedures. In addition, laboratory studies are suggested to determine what changes, if any, are needed to maximize the effectiveness of treatments that are already in use in existing water treatment plants
Angle Kappa and its importance in refractive surgery
Directory of Open Access Journals (Sweden)
Majid Moshirfar
2013-01-01
Full Text Available Angle kappa is the difference between the pupillary and visual axis. This measurement is of paramount consideration in refractive surgery, as proper centration is required for optimal results. Angle kappa may contribute to MFIOL decentration and its resultant photic phenomena. Adjusting placement of MFIOLs for angle kappa is not supported by the literature but is likely to help reduce glare and haloes. Centering LASIK in angle kappa patients over the corneal light reflex is safe, efficacious, and recommended. Centering in-between the corneal reflex and the entrance pupil is also safe and efficacious. The literature regarding PRK in patients with an angle kappa is sparse but centering on the corneal reflex is assumed to be similar to centering LASIK on the corneal reflex. Thus, centration of MFIOLs, LASIK, and PRK should be focused on the corneal reflex for patients with a large angle kappa. More research is needed to guide surgeons′ approach to angle kappa.
Multi-angle Imaging SpectroRadiometer
Diner, David J. (Principal Investigator)
MISR views the sunlit Earth simultaneously at nine widely spaced angles and provides ongoing global coverage with high spatial detail. Its imagery is carefully calibrated to provide accurate measures of the brightness, contrast, and color of reflected sunlight. MISR provides new types of information for scientists studying Earth's climate, such as the regional and global distribution of different types of atmospheric particles and aerosols. The change in reflection at different view angles provides the means to distinguish aerosol types, cloud forms, and land surface cover. Combined with stereoscopic techniques, this enables construction of 3-D cloud models and estimation of the total amount of sunlight reflected by Earth's diverse environments. MISR was built for NASA by the Jet Propulsion Laboratory (JPL) in Pasadena, California. It is part of NASA's first Earth Observing System (EOS) spacecraft, the Terra spacecraft, which was launched into polar orbit from Vandenberg Air Force Base on December 18, 1999. MISR has been continuously providing data since February 24, 2000. [Mission Objectives] The MISR instrument acquires systematic multi-angle measurements for global monitoring of top-of-atmosphere and surface albedos and for measuring the shortwave radiative properties of aerosols, clouds, and surface scenes in order to characterize their impact on the Earth's climate. The Earth's climate is constantly changing -- as a consequence of both natural processes and human activities. Scientists care a great deal about even small changes in Earth's climate, since they can affect our comfort and well-being, and possibly our survival. A few years of below-average rainfall, an unusually cold winter, or a change in emissions from a coal-burning power plant, can influence the quality of life of people, plants, and animals in the region involved. The goal of NASA's Earth Observing System (EOS) is to increase our understanding of the climate changes that are occurring on our
Combinatorial fabrication of composite nanorods using oblique angle co-deposition
Larson, Steven; Huang, Weijie; Zhao, Yiping
2016-09-01
We demonstrate that oblique angle co-deposition can be used as a versatile combinatory nanofabrication technique to generate a library of nanomaterials. Using the Cu-Fe2O3 system as an example, by carefully characterizing the vapor plumes of the source materials, a composition map can be generated, which is used to design the locations of all the substrate holders. The resulting nanostructures at different locations show different thickness, morphology, crystallinity, composition, as well as inhomogeneity in microstructures, and material maps of all these structural parameters are established. By further oxidizing or reducing the composite nanostructures, their properties—such as band gap, photocatalytic performance, and magnetic properties—can be easily linked to their composition and other structural parameters. Optimal materials for photocatalytic and magnetic applications are efficiently identified. It is expected that oblique angle co-deposition and its variations could become the most powerful combinatory nanofabrication technique for nanomaterial survey.
International Nuclear Information System (INIS)
The effect of electrode vertex angle on penetration depth and weld bead width, in automatic tungsten-inert-gas (TIG) dcsp bead-on-plate welding with different currents, has been studied for stainless steel 304L plates 1.5 mm and 8 mm thick. It has been found that for thin plates, wider and deeper welds are obtained when using sharper electrodes while, for thick plates, narrower and deeper welds are produced when blunt electrodes (vertex angle 180 deg) are used. An explanation of the results, based on a literature survey, is included
A wide angle redshift survey of the Hydra-Centaurus region
International Nuclear Information System (INIS)
Radial velocities for 266 galaxies in the region of Hydra Centaurus have been obtained. Examination of this preliminary sample allows a qualitative description of the large-scale distribution of galaxies in the region
Moderate positive spin Hall angle in uranium
Singh, Simranjeet; Anguera, Marta; del Barco, Enrique; Springell, Ross; Miller, Casey W.
2015-12-01
We report measurements of spin pumping and the inverse spin Hall effect in Ni80Fe20/uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on extended films to inject a spin current from the Ni80Fe20 (permalloy) into the uranium layer, which is then converted into an electric field by the inverse spin Hall effect. Surprisingly, our results suggest a spin mixing conductance of order 2 × 1019 m-2 and a positive spin Hall angle of 0.004, which are both merely comparable with those of several transition metals. These results thus support the idea that the electronic configuration may be at least as important as the atomic number in governing spin pumping across interfaces and subsequent spin Hall effects. In fact, given that both the magnitude and the sign are unexpected based on trends in d-electron systems, materials with unfilled f-electron orbitals may hold additional exploration avenues for spin physics.
LDEF yaw and pitch angle estimates
Banks, Bruce A.; Gebauer, Linda
1992-01-01
Quantification of the LDEF yaw and pitch misorientations is crucial to the knowledge of atomic oxygen exposure of samples placed on LDEF. Video camera documentation of the LDEF spacecraft prior to grapple attachment, atomic oxygen shadows on experiment trays and longerons, and a pinhole atomic oxygen camera placed on LDEF provided sources of documentation of the yaw and pitch misorientation. Based on uncertainty-weighted averaging of data, the LDEF yaw offset was found to be 8.1 plus or minus 0.6 degrees, allowing higher atomic oxygen exposure of row 12 than initially anticipated. The LDEF pitch angle offset was found to be 0.8 plus or minus 0.4 degrees, such that the space end was tipped forward toward the direction of travel. The resulting consequences of the yaw and pitch misorientation of LDEF on the atomic oxygen fluence is a factor of 2.16 increase for samples located on row 12, and a factor of 1.18 increase for samples located on the space end compared to that which would be expected for perfect orientation.
Moderate positive spin Hall angle in uranium
Energy Technology Data Exchange (ETDEWEB)
Singh, Simranjeet; Anguera, Marta; Barco, Enrique del, E-mail: delbarco@ucf.edu, E-mail: cwmsch@rit.edu [Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States); Springell, Ross [H. H. Will Laboratory, University of Bristol, Bristol BS2 8BS (United Kingdom); Miller, Casey W., E-mail: delbarco@ucf.edu, E-mail: cwmsch@rit.edu [School of Chemistry and Materials Science, Rochester Institute of Technology, Rochester, New York 14623 (United States)
2015-12-07
We report measurements of spin pumping and the inverse spin Hall effect in Ni{sub 80}Fe{sub 20}/uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on extended films to inject a spin current from the Ni{sub 80}Fe{sub 20} (permalloy) into the uranium layer, which is then converted into an electric field by the inverse spin Hall effect. Surprisingly, our results suggest a spin mixing conductance of order 2 × 10{sup 19} m{sup −2} and a positive spin Hall angle of 0.004, which are both merely comparable with those of several transition metals. These results thus support the idea that the electronic configuration may be at least as important as the atomic number in governing spin pumping across interfaces and subsequent spin Hall effects. In fact, given that both the magnitude and the sign are unexpected based on trends in d-electron systems, materials with unfilled f-electron orbitals may hold additional exploration avenues for spin physics.
Malocclusion Pattern (Angle's) in Mauritian Orthodontic Patients
Durgesh, B. H.; Prakash, Prashanth; Ramakrishnaiah, Ravikumar; Subashchandra Phulari, Basavaraj; Al Kheraif, Abdul Aziz A.
2012-01-01
The aim of the study was to assess the pattern of malocclusion in different ethnic group of Mauritian population visiting the Orthodontic Department at Mauras College of Dentistry and Hospital, Republic of Mauritius. The study population comprised of 624 patients who visited the orthodontic department during 2010. The clinical examination was conducted by a well-calibrated orthodontist. The data were recorded in the case sheets and was analyzed for presence of angles class I, class II, and class III malocclusion in both male and female patients of Asian, African, Caucasian, and Chinese ethnicity aged 5–55 years. Malocclusion was found to be high in females compared to males. 414 patients (150 male + 264 female) presented with class I, 182 patients (52 male + 130 female) presented with class II, and 28 patients (12 male + 16 female) presented with class III. Asian ethnic group were more affected and patient seeking orthodontic treatment was high in 11–15 years age group. PMID:22655203
Impact Angle Control of Interplanetary Shock Geoeffectiveness
Oliveira, D M
2015-01-01
We use OpenGGCM global MHD simulations to study the nightside magnetospheric, magnetotail, and ionospheric responses to interplanetary (IP) fa st forward shocks. Three cases are presented in this study: two inclined oblique shocks, here after IOS-1 and IOS-2, where the latter has a Mach number twice stronger than the former. Both shocks have impact angles of 30$^o$ in relation to the Sun-Earth line. Lastly, we choose a frontal perpendicular shock, FPS, whose shock normal is along the Sun-Earth line, with the same Mach number as IOS-1. We find that, in the IOS-1 case, due to the north-south asymmetry, the magnetotail is deflected southward, leading to a mild compression. The geomagnetic activity observed in the nightside ionosphere is then weak. On the other hand, in the head-on case, the FPS compresses the magnetotail from both sides symmetrically. This compression triggers a substorm allowing a larger amount of stored energy in the magnetotail to be released to the nightside ionosphere, resulting in stronger...
Moderate positive spin Hall angle in uranium
International Nuclear Information System (INIS)
We report measurements of spin pumping and the inverse spin Hall effect in Ni80Fe20/uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on extended films to inject a spin current from the Ni80Fe20 (permalloy) into the uranium layer, which is then converted into an electric field by the inverse spin Hall effect. Surprisingly, our results suggest a spin mixing conductance of order 2 × 1019 m−2 and a positive spin Hall angle of 0.004, which are both merely comparable with those of several transition metals. These results thus support the idea that the electronic configuration may be at least as important as the atomic number in governing spin pumping across interfaces and subsequent spin Hall effects. In fact, given that both the magnitude and the sign are unexpected based on trends in d-electron systems, materials with unfilled f-electron orbitals may hold additional exploration avenues for spin physics
Rubber hand illusion affects joint angle perception.
Directory of Open Access Journals (Sweden)
Martin V Butz
Full Text Available The Rubber Hand Illusion (RHI is a well-established experimental paradigm. It has been shown that the RHI can affect hand location estimates, arm and hand motion towards goals, the subjective visual appearance of the own hand, and the feeling of body ownership. Several studies also indicate that the peri-hand space is partially remapped around the rubber hand. Nonetheless, the question remains if and to what extent the RHI can affect the perception of other body parts. In this study we ask if the RHI can alter the perception of the elbow joint. Participants had to adjust an angular representation on a screen according to their proprioceptive perception of their own elbow joint angle. The results show that the RHI does indeed alter the elbow joint estimation, increasing the agreement with the position and orientation of the artificial hand. Thus, the results show that the brain does not only adjust the perception of the hand in body-relative space, but it also modifies the perception of other body parts. In conclusion, we propose that the brain continuously strives to maintain a consistent internal body image and that this image can be influenced by the available sensory information sources, which are mediated and mapped onto each other by means of a postural, kinematic body model.
Mapping of low flip angles in magnetic resonance
Energy Technology Data Exchange (ETDEWEB)
Balezeau, Fabien; Saint-Jalmes, Herve [LTSI, INSERM U642, Universite Rennes 1 (France); Eliat, Pierre-Antoine [PRISM, IFR 140, Universite Rennes 1 (France); Cayamo, Alejandro Bordelois, E-mail: fabien.balezeau@gmail.com [Centro De BiofIsika Medica, Universidad de Oriente, Santiago de Cuba (Cuba)
2011-10-21
Errors in the flip angle have to be corrected in many magnetic resonance imaging applications, especially for T1 quantification. However, the existing methods of B1 mapping fail to measure lower values of the flip angle despite the fact that these are extensively used in dynamic acquisition and 3D imaging. In this study, the nonlinearity of the radiofrequency (RF) transmit chain, especially for very low flip angles, is investigated and a simple method is proposed to accurately determine both the gain of the RF transmitter and the B1 field map for low flip angles. The method makes use of the spoiled gradient echo sequence with long repetition time (TR), such as applied in the double-angle method. It uses an image acquired with a flip angle of 90{sup 0} as a reference image that is robust to B1 inhomogeneity. The ratio of the image at flip angle alpha to the image at a flip angle of 90{sup 0} enables us to calculate the actual value of alpha. This study was carried out at 1.5 and 4.7 T, showing that the linearity of the RF supply system is highly dependent on the hardware. The method proposed here allows us to measure the flip angle from 1{sup 0} to 60{sup 0} with a maximal uncertainty of 10% and to correct T1 maps based on the variable flip angle method.
Lam, C N C; Wu, R; Li, D; Hair, M L; Neumann, A W
2002-02-25
Two types of experiments were used to study the behavior of both advancing and receding contact angles, namely the dynamic one-cycle contact angle (DOCA) and the dynamic cycling contact angle (DCCA) experiments. For the preliminary study, DOCA measurements of different liquids on different solids were performed using an automated axisymmetric drop shape analysis-profile (ADSA-P). From these experimental results, four patterns of receding contact angle were observed: (1) time-dependent receding contact angle; (2) constant receding contact angle; (3) 'stick/slip'; (4) no receding contact angle. For the purpose of illustration, results from four different solid surfaces are shown. These solids are: FC-732-coated surface; poly(methyl methacrylate/n-butyl methacrylate) [P(MMA/nBMA)]; poly(lactic acid) (DL-PLA); and poly(lactic/glycolic acid) 50/50 (DL-PLGA 50/50). Since most of the surfaces in our studies exhibit time dependence in the receding contact angle, a more extended study was conducted using only FC-732-coated surfaces to better understand the possible causes of decreasing receding contact angle and contact angle hysteresis. Contact angle measurements of 21 liquids from two homologous series (i.e. n-alkanes and 1-alcohols) and octamethylcyclotetrasiloxane (OCMTS) on FC-732-coated surfaces were performed. It is apparent that the contact angle hysteresis decreases with the chain length of the liquid. It was found that the receding contact angle equals the advancing angle when the alkane molecules are infinitely large. These results strongly suggest that the chain length and size of the liquid molecule could contribute to contact angle hysteresis phenomena. Furthermore, DCCA measurements of six liquids from the two homologous series on FC-732-coated surfaces were performed. With these experimental results, one can construe that the time dependence of contact angle hysteresis on relatively smooth and homogeneous surfaces is mainly caused by liquid retention
Numerical aperture characteristics of angle-ended plastic optical fiber
Gao, Cheng; Farrell, Gerard
2003-03-01
With the increasing information rates demanded in consumer, automotive and aeronautical applications, a low cost and high performance physical transmission medium is required. Compared with Silica Optical Fiber, Plastic Optical Fiber (POF) offers an economic solution for a range of high-capacity, short-haul applications in industrial and military environments. Recently, a new type of POF, the perfluorinated graded-index plastic optical fiber (PF GI-POF), has been introduced that has low losses and high bandwidth at the communication wavelengths 850 nm and 1300nm. POF is normally terminated perpendicular to the fiber axis. We propose an angle-ended POF, which is terminated at non-perpendicular angles to the fiber axis. The aim of the research is to investigate the numerical aperture (NA) characteristics of angle-ended POF along the major axis of the elliptical endface. A theoretical model indicates that the NA of the angle-ended POF will increase nonlinearly with tilt-angle and the acceptance cone will be deflected with the angle of the deflection increasing nonlinearly with tilt-angle. We present results for the measured NA and the measured deflection angle using the far-field radiation method. Results are presented for 13 angle-ended SI-POF tilt-angles. We also present results for theoretical value of NA and deflection angle as a function of tilt-angle. The agreement between the measured and theoretical value is good up to tilt-angles of about 15 degrees, beyond which deviation occurs.
Energy Technology Data Exchange (ETDEWEB)
Suzy Cantor-McKinney; Michael Kruzic
2007-03-01
-actuated functions to be controlled by an onboard computer. The computer-controlled Speedrower was developed at Carnegie Mellon University to automate agricultural harvesting. Harvesting tasks require the vehicle to cover a field using minimally overlapping rows at slow speeds in a similar manner to geophysical data acquisition. The Speedrower had demonstrated its ability to perform as it had already logged hundreds of acres of autonomous harvesting. This project is the first use of autonomous robotic technology on a large-scale for geophysical surveying.
Millenium Challenge Corporation — The 2011 MCA-Lesotho baseline enterprise survey is a national survey of enterprises. The main objective of the survey was to assess the current status of businesses...
Contact pressure distribution and support angle optimization of kiln tyre
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
According to the shearing force character and the deformation coordination condition of shell at the station of supports, the mathematical models to calculate contact angle and contact pressure distribution between tyre and shell were set up, the formulae of bending moment and bending stress of tyre were obtained. Taking the maximum of tyre fatigue life as the optimal objective, the optimization model of tyre support angle was built. The computational results show that when tyre support angle is 30°, tyre life is far less than that when tyre support angle is optimal, which is 35.6°, and it is unsuitable to stipulate tyre support angle to be 30° in traditional design. The larger the load, the less the nominal stress amplitude increment of tyre, the more favorable the tyre fatigue life when tyre support angle is optimal.
Elevation angle dependence of the SMA antenna focus position
Matsushita, S; Sakamoto, K; Hunter, T R; Patel, N A; Sridharan, T K; Wilson, R W; Matsushita, Satoki; Saito, Masao; Sakamoto, Kazushi; Hunter, Todd R.; Patel, Nimesh A.; Sridharan, Tirupati K.; Wilson, Robert W.
2006-01-01
We report the measurement results and compensation of the antenna elevation angle dependences of the Sub-millimeter Array (SMA) antenna characteristics. Without optimizing the subreflector (focus) positions as a function of the antenna elevation angle, antenna beam patterns show lopsided sidelobes, and antenna efficiencies show degradations. The sidelobe level increases and the antenna efficiencies decrease about 1% and a few %, respectively, for every 10 degrees change in the elevation angle at the measured frequency of 237 GHz. We therefore obtained the optimized subreflector positions for X (azimuth), Y (elevation), and Z (radio optics) focus axes at various elevation angles for all the eight SMA antennas. The X axis position does not depend on the elevation angle. The Y and Z axes positions depend on the elevation angles, and are well fitted with a simple function for each axis with including a gravity term (cosine and sine of elevation, respectively). In the optimized subreflector positions, the antenna ...
Sunspot group tilt angle measurements from historical observations
Pavai, V Senthamizh; Diercke, A; Denker, C; Vaquero, J M
2016-01-01
Sunspot positions from various historical sets of solar drawings are analysed with respect to the tilt angles of bipolar sunspot groups. Data by Scheiner, Hevelius, Staudacher, Zucconi, Schwabe, and Spoerer deliver a series of average tilt angles spanning a period of 270 years, additional to previously found values for 20th-century data obtained by other authors. We find that the average tilt angles before the Maunder minimum were not significantly different from the modern values. However, the average tilt angles of a period 50 years after the Maunder minimum, namely for cycles 0 and 1, were much lower and near zero. The normal tilt angles before the Maunder minimum suggest that it was not abnormally low tilt angles which drove the solar cycle into a grand minimum.
Can a surgeon drill accurately at a specified angle?
Brioschi, Valentina; Cook, Jodie; Arthurs, Gareth I
2016-01-01
Objectives To investigate whether a surgeon can drill accurately a specified angle and whether surgeon experience, task repetition, drill bit size and perceived difficulty influence drilling angle accuracy. Methods The sample population consisted of final-year students (n=25), non-specialist veterinarians (n=22) and board-certified orthopaedic surgeons (n=8). Each participant drilled a hole twice in a horizontal oak plank at 30°, 45°, 60°, 80°, 85° and 90° angles with either a 2.5 or a 3.5 mm drill bit. Participants then rated the perceived difficulty to drill each angle. The true angle of each hole was measured using a digital goniometer. Results Greater drilling accuracy was achieved at angles closer to 90°. An error of ≤±4° was achieved by 84.5 per cent of participants drilling a 90° angle compared with approximately 20 per cent of participants drilling a 30–45° angle. There was no effect of surgeon experience, task repetition or drill bit size on the mean error for intended versus achieved angle. Increased perception of difficulty was associated with the more acute angles and decreased accuracy, but not experience level. Clinical significance This study shows that surgeon ability to drill accurately (within ±4° error) is limited, particularly at angles ≤60°. In situations where drill angle is critical, use of computer-assisted navigation or custom-made drill guides may be preferable. PMID:27547423
Rotational Angle Measurement of Bridge Support Using Image Processing Techniques
Young-Soo Park; John Arbie Agbayani; Jong-Han Lee; Jong-Jae Lee
2016-01-01
Measuring a very small rotational angle accurately and dynamically is indeed a challenging issue, especially in the case of bridge support. Also, existing inclinometers do not have sufficient resolution and accuracy to measure a bridge’s rotational angle. In this study, a new measurement system was developed to provide a practical means for measuring dynamic rotational angle of a bridge support. It features high resolution and accuracy compared with the available systems on the market. By the...
Orientation angle and the adhesion of single gecko setae
Hill, Ginel C.; Soto, Daniel R.; Peattie, Anne M.; Full, Robert J.; Kenny, T. W.
2011-01-01
We investigated the effects of orientation angle on the adhesion of single gecko setae using dual-axis microelectromechanical systems force sensors to simultaneously detect normal and shear force components. Adhesion was highly sensitive to the pitch angle between the substrate and the seta's stalk. Maximum lateral adhesive force was observed with the stalk parallel to the substrate, and adhesion decreased smoothly with increasing pitch. The roll orientation angle only needed to be roughly co...
Escape angles in bulk chi((2)) soliton interactions
Johansen, Steffen Kjær; Bang, Ole; Sørensen, Mads Peter
2002-01-01
We develop a theory for nonplanar interaction between two identical type I spatial solitons propagating at opposite, but arbitrary transverse angles in quadratic nonlinear (or so-called chi((2))) bulk, media. We predict quantitatively the outwards escape angle, below which the solitons turn around and collide, and above which they continue to move-away from each other. For in-plane interaction, the theory allows prediction of the Outcome of a collision through the inwards escape angle, i.e., ...
Citalopram associated with acute angle-closure glaucoma: case report
Hassan Sabit; Thirumalai Srinivasa; Croos Robert; Davis Jane
2005-01-01
Abstract Background Acute angle-closure glaucoma is a rare complication in patients receiving anti-depressant treatment. In the following case, we report the development of acute angle closure glaucoma in a patient who overdosed on Citalopram, an antidepressant, and discuss the possible etiological mechanisms for the condition. Case presentation We report a 54 year old, Caucasian lady, with depression and alcohol dependence syndrome, who developed acute angle-closure glaucoma after an overdos...
On extracting quark mixing angles in B meson decays
International Nuclear Information System (INIS)
After emphasizing the fundamental importance of determining the mixing angles of bottom quarks we list and discuss the considerable systematic uncertainties one faces when extracting these mixing angles from B decays. Evaluating various methods suggested we conclude that a study of the lepton energy spectrum in B decays provides a reasonable way of obtaining the ratio of mixing angles; yet in view of its inherent hazards its results should be backed up by other studies based, e.g., on kaon multiplicities
Tibial and fibular angles in homozygous sickle cell disease
Energy Technology Data Exchange (ETDEWEB)
Akamaguna, A.I.; Odita, J.C.; Ugbodaga, C.I.; Okafor, L.A.
1986-05-01
Measurements of the tibial and fibular angles made on ankle radiographs of 34 patients with sickle cell disease were compared with those of 36 normal Nigerians. Widening of the fibular angle, which is an indication of tibiotalar slant, was demonstrated in about 79% of sickle cell disease patients. By using fibular angle measurements as an objective method of assessing subtle tibiotalar slant, it is concluded that the incidence of this deformity is much higher among sickle cell disease patients than previously reported. The mean values of tibial and fibular angles in normal Nigerians are higher than has been reported amongst Caucasians.
Tibial and fibular angles in homozygous sickle cell disease
International Nuclear Information System (INIS)
Measurements of the tibial and fibular angles made on ankle radiographs of 34 patients with sickle cell disease were compared with those of 36 normal Nigerians. Widening of the fibular angle, which is an indication of tibiotalar slant, was demonstrated in about 79% of sickle cell disease patients. By using fibular angle measurements as an objective method of assessing subtle tibiotalar slant, it is concluded that the incidence of this deformity is much higher among sickle cell disease patients than previously reported. The mean values of tibial and fibular angles in normal Nigerians are higher than has been reported amongst Caucasians. (orig.)
Lateral intermetatarsal angle: a useful measurement of metatarsus primus elevatus?
Bryant, A; Mahoney, B; Tinley, P
2001-05-01
The lateral intermetatarsal angle, a measurement of the sagittal plane angular divergence between the dorsal cortices of the first and second metatarsals of lateral weightbearing foot radiographs, was compared in 30 normal and 30 hallux limitus feet. The results suggest that the angle may be measured reliably and that although the measured angles are relatively small, a significant difference exists between the normal and hallux limitus subjects studied. Accordingly, the lateral intermetatarsal angle may prove to be a useful radiographic measurement to assist the podiatric physician in the clinical assessment of hallux limitus. PMID:11359890
Tachometer Derived From Brushless Shaft-Angle Resolver
Howard, David E.; Smith, Dennis A.
1995-01-01
Tachometer circuit operates in conjunction with brushless shaft-angle resolver. By performing sequence of straightforward mathematical operations on resolver signals and utilizing simple trigonometric identity, generates voltage proportional to rate of rotation of shaft. One advantage is use of brushless shaft-angle resolver as main source of rate signal: no brushes to wear out, no brush noise, and brushless resolvers have proven robustness. No switching of signals to generate noise. Another advantage, shaft-angle resolver used as shaft-angle sensor, tachometer input obtained without adding another sensor. Present circuit reduces overall size, weight, and cost of tachometer.
Energy Technology Data Exchange (ETDEWEB)
Hu Tao [Department of Automation, Shanghai University, 149 Yanchang Rd., Shanghai 200072 (China); Shao Zhengyi [Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Rd., Shanghai 200030 (China); Peng Qiuhe, E-mail: thu@shu.edu.cn, E-mail: taohu.nju@gmail.com [Department of Astronomy, Nanjing University, 22 Hankou Rd., Nanjing 210093 (China)
2013-01-10
The inclination (i) and position angle (PA) of the Whirlpool galaxy (M51) are critical to modeling and interpreting observations. Here we make improved estimates of these parameters by fitting logarithmic spirals to the main arms. From separate fits to each major arm, we obtain i = 20. Degree-Sign 3 {+-} 2. Degree-Sign 8 and PA = 12. Degree-Sign 0 {+-} 2. Degree-Sign 5. We then use Poisson's equation for the logarithmic perturbation of the density to estimate the mean vertical scale height (H) of M51 to be 95-178 pc.
Virtuts castrenses de l'angle recte
Directory of Open Access Journals (Sweden)
Antonio Bustamante
2003-01-01
Full Text Available Está muy arraigada la idea de que, en una postura sedente sana, los segmentos corporales han de orientarse en ángulo recto. La desinformación que encierra esta idea es demasiado evidente y puede parecer fácil, a primera vista, retirar de la circulación esta paradójica receta; pero no es así. La pertinaz veneración de lo ortogonal que, en lo postural, se encuentra por doquier, ha hecho sospechar al autor que la fuerza de los 90° no se debe a errores de apreciación biomecánica, sino a simbologías cuyo origen, si no se pierde en la noche de los tiempos, sí que aparece en la aurora del Neolítico. Este artículo trata de mostrar que si lo ortogonal está justificado por la cultura para la construcción de objetos, no lo está para la adopción de posturas sedentes. _____________________________________________________________________________________________________________________________________________________________________ L’idée est profondément ancrée dans les esprits que dans une position assise correcte les segments corporaux doivent former entre eux une série d’angles droits. L’ignorance qui se cache derrière cette conception semble à priori trop évidente et devrait être facile à combattre, or tel n’est pas le cas. La vénération persistante de la position orthogonale est si étendue qu’elle a amené l’auteur à soupçonner que le culte des 90 degrés n’est pas dû à des erreurs d’appréciation biomécaniques mais à une forte symbologie dont les origines si elles ne remontent pas à la nuit des temps, renvoient au moins à l’aube du Néolithique. L’article essaie de démontrer que si la position orthogonale est culturellement justifiée pour la fabrication d’objets elle ne l’est pas de façon systématique pour ce qui de s’asseoir.The idea is well-rooted that in a healthy sitting position the segments of the body have to adopt a right angle. The disinformation surrounding this idea is
46 CFR 58.01-40 - Machinery, angles of inclination.
2010-10-01
... 46 Shipping 2 2010-10-01 2010-10-01 false Machinery, angles of inclination. 58.01-40 Section 58.01... AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-40 Machinery, angles of inclination. (a) Propulsion machinery and all auxiliary machinery essential to the propulsion and safety of the vessel must...
Bite angle effects of diphosphines in carbonylation reactions
P.W.N.M. van Leeuwen; Z. Freixa
2008-01-01
This chapter contains sections titled: * Introduction * Rhodium-Catalyzed Hydroformylation o Introduction o Steric Bite Angle Effect and Regioselectivity o Electronic Bite Angle Effect and Activity o Isotope Effects [24] * Platinum-Catalyzed Alkene Hydroformylation * Palladium-Catalyzed CO/Ethene Co
Escape angles in bulk chi((2)) soliton interactions
DEFF Research Database (Denmark)
Johansen, Steffen Kjær; Bang, Ole; Sørensen, Mads Peter
2002-01-01
We develop a theory for nonplanar interaction between two identical type I spatial solitons propagating at opposite, but arbitrary transverse angles in quadratic nonlinear (or so-called chi((2))) bulk, media. We predict quantitatively the outwards escape angle, below which the solitons turn aroun...
EVALUATION OF NECK SHAFT ANGLE OF FEMUR ON DRY BONES
Directory of Open Access Journals (Sweden)
Radha
2015-04-01
Full Text Available BACKGROUND: Evaluation of the neck shaft angle of femur helps to understand clinical relevance in bio mechanics of the hip joint. It helps for the better treatment of different pathological conditions of hip and femur and also to design prosthesis. Femoral neck shaft angle is important to convey the information regarding the race to which they belong. Hence the present study was under taken to determine the neck shaft angle of femur in humans. OBJECTIVE: 1. To correct the different types of deformity and to have a normal good walking Mechanism. 2. To know the recent methodology and attempt to evaluate the range of normal Angles of femora and their sex differences. METHODS: ANTHROPOMETRIC: 100 Adult dry bones were studied and analyzed . The neck shaft angle of femur was measured by tracing outlines of contours of all femora. RESULTS: The neck shaft angle of the femur have revealed that there is no much difference in between males and females. There was slightly higher 0.2° in females. INTERPRETATION & CONCLUSION: There was no significant gender difference in neck shaft angle. The Knowledge of knowing the neck shaft angle helps to understand the Biomechanics of the hip joint and also for better treatment of pathological condition of hip and femur.
Note on four Dp-branes at angles
International Nuclear Information System (INIS)
In this note we analyse the dynamical potential of a system of four Dp-branes at arbitrary angles. The equilibrium configurations for various values of the relative angles and distances among branes are discussed. The known configurations of parallel branes and brane-antibranes are obtained at extrema of the dynamical potential. (author)
Note on Four Dp-Branes at Angles
Vancea, Ion-Vasile
2001-04-01
In this note we analyse the dynamical potential of a system of four Dp-branes at arbitrary angles. The equilibrium configurations for various values of the relative angles and distances among branes are discussed. The known configurations of parallel branes and brane-antibranes are obtained at extrema of the dynamical potential.
Note on Four Dp-Branes at Angles
Vancea, Ion V.
2000-01-01
In this note we analyse the dynamical potential of a system of four $Dp$-branes at arbitrary angles. The equilibrium configurations for various values of the relative angles and distances among branes are discussed. The known configurations of parallel branes and brane-antibranes are obtained at extrema of the dynamical potential.
The effective take-off angle in PHI Quantera systems
Van der Marel, C.
2010-01-01
It is well known that for quantitative analysis of XPS results theeffective take-off angle of the electrons is an important parameter.In the report is shown that the effective take-off angle i n PHI Quantera systems deviates significanlty from the set value. This is NOT a consequence of inadequa
A Novel Monopulse Angle Estimation Method for Wideband LFM Radars
Directory of Open Access Journals (Sweden)
Yi-Xiong Zhang
2016-06-01
Full Text Available Traditional monopulse angle estimations are mainly based on phase comparison and amplitude comparison methods, which are commonly adopted in narrowband radars. In modern radar systems, wideband radars are becoming more and more important, while the angle estimation for wideband signals is little studied in previous works. As noise in wideband radars has larger bandwidth than narrowband radars, the challenge lies in the accumulation of energy from the high resolution range profile (HRRP of monopulse. In wideband radars, linear frequency modulated (LFM signals are frequently utilized. In this paper, we investigate the monopulse angle estimation problem for wideband LFM signals. To accumulate the energy of the received echo signals from different scatterers of a target, we propose utilizing a cross-correlation operation, which can achieve a good performance in low signal-to-noise ratio (SNR conditions. In the proposed algorithm, the problem of angle estimation is converted to estimating the frequency of the cross-correlation function (CCF. Experimental results demonstrate the similar performance of the proposed algorithm compared with the traditional amplitude comparison method. It means that the proposed method for angle estimation can be adopted. When adopting the proposed method, future radars may only need wideband signals for both tracking and imaging, which can greatly increase the data rate and strengthen the capability of anti-jamming. More importantly, the estimated angle will not become ambiguous under an arbitrary angle, which can significantly extend the estimated angle range in wideband radars.
A Novel Monopulse Angle Estimation Method for Wideband LFM Radars.
Zhang, Yi-Xiong; Liu, Qi-Fan; Hong, Ru-Jia; Pan, Ping-Ping; Deng, Zhen-Miao
2016-01-01
Traditional monopulse angle estimations are mainly based on phase comparison and amplitude comparison methods, which are commonly adopted in narrowband radars. In modern radar systems, wideband radars are becoming more and more important, while the angle estimation for wideband signals is little studied in previous works. As noise in wideband radars has larger bandwidth than narrowband radars, the challenge lies in the accumulation of energy from the high resolution range profile (HRRP) of monopulse. In wideband radars, linear frequency modulated (LFM) signals are frequently utilized. In this paper, we investigate the monopulse angle estimation problem for wideband LFM signals. To accumulate the energy of the received echo signals from different scatterers of a target, we propose utilizing a cross-correlation operation, which can achieve a good performance in low signal-to-noise ratio (SNR) conditions. In the proposed algorithm, the problem of angle estimation is converted to estimating the frequency of the cross-correlation function (CCF). Experimental results demonstrate the similar performance of the proposed algorithm compared with the traditional amplitude comparison method. It means that the proposed method for angle estimation can be adopted. When adopting the proposed method, future radars may only need wideband signals for both tracking and imaging, which can greatly increase the data rate and strengthen the capability of anti-jamming. More importantly, the estimated angle will not become ambiguous under an arbitrary angle, which can significantly extend the estimated angle range in wideband radars. PMID:27271629
Brocard angle of the standard triangle in an isotropic plane
Kolar-Begović, Zdenka; Kolar - Šuper, Ružica; Volenec, Vladimir
2009-01-01
The concept of Brocard angle of the standard triangle in an isotropic plane I2 is introduced. The relationships between Brocard angles of the allowable triangle and circum-Ceva’s triangle of its centroid and circum-Ceva’s triangle of its Feuerbach point are investigated.
A gallery approach for off-angle iris recognition
Karakaya, Mahmut; Yoldash, Rashiduddin; Boehnen, Christopher
2015-05-01
It has been proven that hamming distance score between frontal and off-angle iris images of same eye differs in iris recognition system. The distinction of hamming distance score is caused by many factors such as image acquisition angle, occlusion, pupil dilation, and limbus effect. In this paper, we first study the effect of the angle variations between iris plane and the image acquisition systems. We present how hamming distance changes for different off-angle iris images even if they are coming from the same iris. We observe that increment in acquisition angle of compared iris images causes the increment in hamming distance. Second, we propose a new technique in off-angle iris recognition system that includes creating a gallery of different off-angle iris images (such as, 0, 10, 20, 30, 40, and 50 degrees) and comparing each probe image with these gallery images. We will show the accuracy of the gallery approach for off-angle iris recognition.
A new uncertainty relation for angular momentum and angle
International Nuclear Information System (INIS)
An uncertainty relation of the form ΔL2ΔSo >=sup(h/2π)/sub(2) is derived for angular momentum and angle. The non-linear operator So measures angles and has a simple interpretation. Subject to very general conditions of rotational invariance the above relation is unique. Radial momentum is not quantized
EVALUATION OF NECK SHAFT ANGLE OF FEMUR ON DRY BONES
Radha; Ravi Shankar; Naveen; Roopa
2015-01-01
BACKGROUND: Evaluation of the neck shaft angle of femur helps to understand clinical relevance in bio mechanics of the hip joint. It helps for the better treatment of different pathological conditions of hip and femur and also to design prosthesis. Femoral neck shaft angle is important to convey the information regarding the race to ...
Low angle neutron data acquisition system for molecular biology
International Nuclear Information System (INIS)
The low angle spectrometer system utilizing a 2-dimensional position sensitive counter was designed to accommodate a variety of experiments in molecular biology requiring good low angle resolution. Biological structures requiring low angle analysis techniques fall into two groups: non-ordered systems (proteins or protein complexes in solution) and ordered systems with large spacings like muscle, collagen, and membranes. For structural investigations into such systems, data are ideally needed to a low scattering angle of 0.20 at 4.5 A or a minimum Q of 0.005 A-1 (Q = theta . 2π/lambda). Depending on the type of structure, data often extend to the high angle region, say 300. Apart from the low angle requirements, the spectrometer has to have good resolution to resolve diffraction peaks from samples with crystal spacings up to 1000 A or even larger. While it is desirable to build a spectrometer to such scattering conditions, given reactor conditions might not permit this and compromises have to be made between flux, resolution and lowest angle. The low angle spectrometer described here was designed to be used at the HFBR neutron beam pipe working at approximately 4.2 A or at the H4 satellite station working at 2.4 A
Kevin O. Shropshire; Hawdon, James E.; James C. Witte
2009-01-01
Using data from Survey2001, we analyze how visual images embedded in a web-based survey can (1) reduce nonresponse in the specific case that a respondent prematurely terminates the survey and (2) preserve measurement validity. Page-by-page progression through the survey is modeled as a survival process with early termination seen as failure. While images had no apparent effect on the termination process, respondent interest in the survey topic was linked to early termination. These results hi...
The effect of knee joint angle on torque control.
Sosnoff, Jacob J; Voudrie, Stefani J; Ebersole, Kyle T
2010-01-01
The purpose of the author's investigation was to examine the effect of knee joint angle on torque control of the quadriceps muscle group. In all, 12 healthy adults produced maximal voluntary contractions and submaximal torque (15, 30, and 45% MVC [maximal voluntary contraction]) at leg flexion angles of 15 degrees , 30 degrees , 60 degrees , and 90 degrees below the horizontal plane. As expected, MVC values changed with respect to joint angle with maximum torque output being greatest at 60 degrees and least at 15 degrees . During the submaximal tasks, participants appropriately scaled their torque output to the required targets. Absolute variability (i.e., standard deviation) of torque output was greatest at 60 degrees and 90 degrees knee flexion. However, relative variability as indexed by coefficient of variation (CV) decreased as joint angle increased, with the greatest CV occurring at 15 degrees . These results are congruent with the hypothesis that joint angle influences the control of torque. PMID:19906637
Contact angles in the pseudopotential lattice Boltzmann modeling of wetting
Li, Q; Kang, Q J; Chen, Q
2014-01-01
In this paper, we aim to investigate the implementation of contact angles in the pseudopotential lattice Boltzmann modeling of wetting at a large density ratio. The pseudopotential lattice Boltzmann model [X. Shan and H. Chen, Phys. Rev. E 49, 2941 (1994)] is a popular mesoscopic model for simulating multiphase flows and interfacial dynamics. In this model, the contact angle is usually realized by a fluid-solid interaction. Two widely used fluid-solid interactions: the density-based interaction and the pseudopotential-based interaction, as well as a modified pseudopotential-based interaction formulated in the present paper, are numerically investigated and compared in terms of the achievable contact angles, the maximum and the minimum densities, and the spurious currents. It is found that the pseudopotential-based interaction works well for simulating small static (liquid) contact angles, however, is unable to reproduce static contact angles close to 180 degrees. Meanwhile, it is found that the proposed modif...
Stable divergence angles of a magnetic dipole spiral array
Energy Technology Data Exchange (ETDEWEB)
Fan, X.D.; Bursill, L.A.
1996-03-01
An analytical model is introduced for Douady and Couder`s [1992] experiment, where phyllotactic patterns appear as a dynamical result of the interaction between magnetic dipoles. The difference equation for the divergence angle (i.e. the angle between successive radial vectors) is obtained by solving the equations of motion with a second nearest neighbour (SNN) approximation. A one dimensional map analysis as well as a comprehensive analytical proof shows that the divergence angle always converges to a single attractor regardless of the initial conditions. This attractor is approximately the Fibonacci angle ({approx} 138 deg) within variations due to a growth factor {mu} of the pattern. The system is proved to be stable with the SNN approximation. Further analysis with a third nearest neighbour approximation (TNN) shows extra linearly stable attractors may appear around the Lucas angle at {approx} 99.5 deg. 7 refs., 5 figs.
[The sulcus angle of the femoral trochlea: ultrasonographic evaluation].
Martino, F; De Serio, A; Macarini, L; Colaianni, P; Solarino, M; Fracella, M R
1995-03-01
The sulcus angle of femoral trochlea is particularly important to evaluate the femoro-patellar joint. Our study was aimed at studying the normal trochlea, and especially the sulcus angle, with US. The right knees of 11 normal subjects were examined with US and Computed Tomography (CT) on the same section planes. The US measurements of the sulcus angle were correlated with CT results, which were considered the gold standard. The US and CT data were compared and a direct correlation was found (r = 0.832). The intraobserver difference in US measurements was r = 0.943. The mean sulcus angle value was 132 degrees, in agreement with literature data. We conclude that the US measurements of the sulcus angle are reproducible and as sensitive as CT. PMID:7754110
New mixing angles in the left-right symmetric model
Kokado, Akira; Saito, Takesi
2015-12-01
In the left-right symmetric model neutral gauge fields are characterized by three mixing angles θ12,θ23,θ13 between three gauge fields Bμ,WLμ 3,WRμ 3, which produce mass eigenstates Aμ,Zμ,Zμ', when G =S U (2 )L×S U (2 )R×U (1 )B-L×D is spontaneously broken down until U (1 )em . We find a new mixing angle θ', which corresponds to the Weinberg angle θW in the standard model with the S U (2 )L×U (1 )Y gauge symmetry, from these mixing angles. It is then shown that any mixing angle θi j can be expressed by ɛ and θ', where ɛ =gL/gR is a ratio of running left-right gauge coupling strengths. We observe that light gauge bosons are described by θ' only, whereas heavy gauge bosons are described by two parameters ɛ and θ'.
Sampling survey methodology issues of SBS- survey
Liljana Boci; Elona Berberi
2015-01-01
This paper aims at providing an insight on what is required to build an efficient and high quality business statistics from sample survey procedures, and on the effective and appropriate use of survey data in analysis. It aims at describing a general overview of what is required to have a good survey estimate. It shows in practice how to estimate characteristics of the population in SBS considering: weighting, non-response adjustments, post stratification, estimating a population totals, the ...
On regular seven-membered loops in R^3 with arbitrary join angle
Cox, Barry J.
2016-06-01
The problem of ring molecules and macromolecules arises in a number of contexts in physical chemistry. Perhaps the simplest example of a seven-membered loop is cycloheptane C_{7H_{14}}, which is a molecule where the carbon-carbon bonds form a regular seven-membered loop. However, it is possible to envisage much more complicated arrangements of proteins in chains comprising straight rigid sections linked in ways that enforce the same angle at all of the joins. In this paper, we present a coordinate system that reduces the problem to four free variables and three constraints. We then survey the solutions numerically and find that there are families of solutions for all join angles {θ} between {π/7} and {5π/7} with fixed planar solutions existing for {θ = π/7}, {3π/7} and {5π/7}. The available families of solutions undergo a major reorganisation at the join angle {θ = π/3}, where 28 intersecting solutions form a single connected network of configurations.
Chaminade, B; Zographos, S; Uthéza, G
2001-11-01
In 1931, Böhler proposed that measuring the radiological angle of the tuberosity could be useful in posterior facet fractures of the calcaneus to evaluate initial damage as well as reduction quality. In opposition to the 1998 SOFCOT symposium, certain authors considered that the Böhler angle has no prognostic value. Progress in pathological anatomy has helped to better understand posterior facet fractures, justifying the use of a "double measurement". The fundamental fracture line separates the posterior facet into a lowered medial fragment and a pivoted lateral fragment. The double contour of the posterior facet visualized radiographically allows measurement of a medial Böhler angle and a lateral Böhler angle. It is demonstrated that is the smaller the medial Böhler angle, the greater the subtalar degeneration. Surgical restoration of a satisfactory Böhler angle is a necessary prerequisite for a good outcome. "Double measurement" of the Böhler angle on the lateral view contributes to the prognostic value of this historical angle. PMID:11845075
Directory of Open Access Journals (Sweden)
Hideaki Tanoue
2013-07-01
Full Text Available The body tilt angle of a fish has a large effect on the acoustic target strength. For an accurate estimation of fish abundance using acoustic methods, it is necessary to measure body tilt angles in free-ranging fish. We measured diurnal body tilt angle distributions of threeline grunt (Parapristipoma trilineatum while swimming in schools in a fish cage. Micro-acceleration data loggers were used to record (for 3 days swaying and surging accelerations (at 16 Hz intervals of 10 individuals among 20 forming a school in a fish cage. Time series analysis of 1-h mean body tilt angles revealed significant differences in body tilt angles between day (−7.9 ± 3.28° and night (0.8 ± 5.89°, which must be taken into account when conducting acoustic surveys. These results will be useful for calculating the average dorsal aspect target strength (TS of threeline grunt for accurate estimations of fish abundance.
EFFECT OF SWEEP ANGLE ON THE VORTICAL FLOW OVER DELTA WINGS AT AN ANGLE OF ATTACK OF 10°
Directory of Open Access Journals (Sweden)
JAMES BRETT
2014-12-01
Full Text Available CFD simulations have been used to analyse the vortical flows over sharp edged delta wings with differing sweep angles under subsonic conditions at an angle of attack of 10°. RANS simulations were validated against experimental data for a 65° sweep wing, with a flat cross-section, and the steadiness of the flow field was assessed by comparing the results against unsteady URANS and DES simulations. To assess the effect of sweep angle on the flow field, a range of sweep angles from 65° to 43° were simulated. For moderate sweep wings the primary vortex was observed to detach from the leading edge, undergoing vortex breakdown, and a weaker, replacement, "shadow" vortex was formed. The shadow vortex was observed for sweep angles of 50° and less, and resulted in reduced lift production near the wing tips loss of the stronger primary vortex.
The range of options for handling plane angle and solid angle within a system of units
Quincey, Paul
2016-04-01
The radian and steradian are unusual units within the SI, originally belonging to their own category of ‘supplementary units’, with this status being changed to dimensionless ‘derived units’ in 1995. Recent papers have suggested that angles could be handled in two different ways within the SI, both differing from the present system. The purpose of this paper is to provide a framework for putting such suggestions into context, outlining the range of options that is available, together with the advantages and disadvantages of these options. Although less rigorously logical than some alternatives, the present SI approach is generally supported, but with some changes to the SI brochure to make the position clearer, in particular with regard to the designation of the radian and steradian as derived units.
The environmental survey manual
International Nuclear Information System (INIS)
The purpose of this manual is to provide guidance to the Survey and Sampling and Analysis teams that conduct the one-time Environmental Survey of the major US Department of Energy (DOE) operating facilities. This manual includes a discussion of DOE's policy on environmental issues, a review of statutory guidance as it applies to the Survey, the procedures and protocols to be used by the Survey teams, criteria for the use of the Survey teams in evaluating existing environmental data for the Survey effort, generic technical checklists used in every Survey, health and safety guidelines for the personnel conducting the Survey, including the identification of potential hazards, prescribed protective equipment, and emergency procedures, the required formats for the Survey reports, guidance on identifying environmental problems that need immediate attention by the Operations Office responsible for the particular facility, and procedures and protocols for the conduct of sampling and analysis
Going round the bend: Persistent personal biases in walked angles.
Jetzschke, Simon; Ernst, Marc O; Moscatelli, Alessandro; Boeddeker, Norbert
2016-03-23
For navigation through our environment, we can rely on information from various modalities, such as vision and audition. This information enables us for example to estimate our position relative to the starting position, or to integrate velocity and acceleration signals from the vestibular organ and proprioception to estimate the displacement due to self-motion. To better understand the mechanisms that underlie human navigation we analysed the performance of participants in an angle-walking task in the absence of visual and auditory signals. To this end, we guided them along paths of different lengths and asked them to turn by an angle of ±90°. We found significant biases in turn angles, i.e. systematic deviations from the correct angle and that these were characteristic for individual participants. Varying path length, however, had little effect on turn accuracy and precision. To check whether this idiosyncrasy was persistent over time and present in another type of walking task, we performed a second experiment several weeks later. Here, the same participants were guided to walk angles with varying amplitude. We then asked them to judge whether they had walked an angle larger or smaller than 90° in a two-alternative forced-choice paradigm. The personal bias was highly correlated between the two experiments even though they were conducted weeks apart. The presence of a persistent bias in walked angles in the absence of external directional cues indicates a possible error component for navigation, which is surprisingly time stable and idiosyncratic. PMID:26854843
Geometric relation for neutrino mixing angles and theta(13)
Lipmanov, E M
2011-01-01
Inspired by the recent T2K discovery of a relatively large theta(13) angle in the neutrino mixing matrix we propose here a simple geometric relation between the three usually thought "independent" neutrino mixing angles - solar {\\theta}12, atmospheric {\\theta}23 and reactor {\\theta}13 ones: cos2(2{\\theta}sol) + cos2(2{\\theta}atm) + cos2(2{\\theta}13) = 1. Using the estimations for the two largest neutrino mixing angles from experimental data analyses in the literature, {\\theta}sol{\\cong} ~ 34.4o, {\\theta}atm{\\cong} ~ 42.8o, the reactor neutrino mixing angle is uniquely predicted {\\theta}13 = 10.8o. In case a little changed data, {\\theta}sol{\\cong} = 34o and {\\theta}atm{\\cong} = 43o the result will be {\\theta}13 =11.2o. And so, the {\\theta}13-value is not very sensitive to the accurate magnitudes of the two largest mixing angles. That prediction for the 'small' neutrino mixing angle is compatible with the latest T2K experimental data with best fit values for the reactor angle ({\\theta}13)bf{\\cong}= 9.7o(11o) fo...
RESEARCH OF BASIFACIAL CONTOURING SCULPTURE BY MANDIBULAR ANGLE OSTECTOMY
Institute of Scientific and Technical Information of China (English)
FANG Jian-lin; DAI Chuan-chang; ZHU Guo-xian; ZHANG Ying; JIN Yu-qing; WANG Wei; QI Chuan-liang
2006-01-01
Objective Mandibular angle ostectomy is usually applied to the facial contouring sculpture.We evaluated the various techniques in order to enhance the precision and avoid unnecessary damage. Methods Before operation the area and quantity resected bone were designed according to facial measurement, mandible pantomography and orthophoria and lateral localized radiograph of skull. The Incises of mandibular angle ostectomy included intraoral, retroauricular or intraoral associated with retroauricular. Howerer, the sagittal resection of mandible outer table was necessary in all intraoral incise. Results Single mandibular angle ostectomy was not satisfactory for the patients having mandible hypertrophy with over-width basifacial contouring. Mandibular angle ostectomy combined with the sagittal resection of outer table of mandibular angle were required. Good symmetry and ap pearance were gained in 206 cases. One case had facial paralysis. Two patients occured mandibular fracture during the operation. Three cases complicated angled deformity at mandible body. Conclusion Reduction mandibuloplasty should be selected depends on varied types of mandibular angle hypertrophy before operation.
Viewing angle switching of patterned vertical alignment liquid crystal display
International Nuclear Information System (INIS)
Viewing angle control of a patterned vertical alignment (PVA) liquid crystal display using only one panel is investigated. In conventional PVA modes, a vertically aligned liquid crystal (LC) director tilts down in four directions making 45 deg. with respect to crossed polarizers to exhibit a wide viewing angle. In the viewing angle control device, one pixel was divided into two sub-pixels such that the LC director in the main pixel is controlled to be tilted down in multiple directions making an angle with the polarizer, playing the role of main display with the wide viewing angle, while the LC director in the sub-pixel is controlled to be tilted down to the polarizer axis, playing the role of sub-pixel to the viewing angle control for the narrow viewing angle. Using sub-pixel control, light leakage or any type of information such as characters and image can be generated in oblique viewing directions without distorting the image quality in the normal direction, which will prevent others from peeping at the displayed image by overlapping the displayed image with the made image
Operational multi-angle hyperspectral remote sensing for feature detection
Bostater, Charles R.; Brooks, Donald K.
2013-10-01
Remote sensing results of land and water surfaces from airborne and satellite platforms are dependent upon the illumination geometry and the sensor viewing geometry. Correction of pushbroom hyperspectral imagery can be achieved using bidirectional reflectance factors (BRF's) image features based upon their multi-angle hyperspectral signatures. Ground validation of features and targets utilize non-imaging sensors such as hemispherical goniometers. In this paper, a new linear translation based hyperspectral imaging goniometer system is described. Imagery and hyperspectral signatures obtained from a rotation stage platform and the new linear non-hemispherical goniometer system shows applications and a multi-angle correction approach for multi-angle hyperspectral pushbroom imagery corrections. Results are presented in a manner in order to describe how ground, vessel and airborne based multi-angle hyperspectral signatures can be applied to operational hyperspectral image acquisition by the calculation of hyperspectral anisotropic signature imagery. The results demonstrate the analysis framework from the systems to water and coastal vegetation for exploitation of surface and subsurface feature or target detection based using the multi-angle radiative transfer based BRF's. The hyperspectral pushbroom multi-angle analysis methodology forms a basis for future multi-sensor based multi-angle change detection algorithms.
Dynamic angle selection in X-ray computed tomography
Energy Technology Data Exchange (ETDEWEB)
Dabravolski, Andrei, E-mail: andrei.dabravolski@uantwerpen.be [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Batenburg, Kees Joost, E-mail: joost.batenburg@uantwerpen.be [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Centrum Wiskunde and Informatica (CWI), Science Park 123, 1098 XG Amsterdam (Netherlands); Sijbers, Jan, E-mail: jan.sijbers@uantwerpen.be [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium)
2014-04-01
Highlights: • We propose the dynamic angle selection algorithm for CT scanning. • The approach is based on the concept of information gain over a set of solutions. • Projection angles are selected based on the already available projection data. • The approach can lead to more accurate results from fewer projections. - Abstract: In X-ray tomography, a number of radiographs (projections) are recorded from which a tomogram is then reconstructed. Conventionally, these projections are acquired equiangularly, resulting in an unbiased sampling of the Radon space. However, especially in case when only a limited number of projections can be acquired, the selection of the angles has a large impact on the quality of the reconstructed image. In this paper, a dynamic algorithm is proposed, in which new projection angles are selected by maximizing the information gain about the object, given the set of possible new angles. Experiments show that this approach can select projection angles for which the accuracy of the reconstructed image is significantly higher compared to the standard angle selections schemes.
A study of images of Projective Angles of pulmonary veins
Energy Technology Data Exchange (ETDEWEB)
Wang Jue [Beijing Anzhen Hospital, Beijing (China); Zhaoqi, Zhang [Beijing Anzhen Hospital, Beijing (China)], E-mail: zhaoqi5000@vip.sohu.com; Yu Wei; Miao Cuilian; Yan Zixu; Zhao Yike [Beijing Anzhen Hospital, Beijing (China)
2009-09-15
Aims: In images of magnetic resonance and computed tomography (CT) there are visible angles between pulmonary veins and the coronary, transversal or sagittal section of body. In this study these angles are measured and defined as Projective Angles of pulmonary veins. Several possible influential factors and characters of distribution are studied and analyzed for a better understanding of this imaging anatomic character of pulmonary veins. And it could be the anatomic base of adjusting correctly the angle of the central X-ray of the angiography of pulmonary veins undergoing the catheter ablation of atrial fibrillation (AF). Method: Images of contrast enhanced magnetic resonance angiography (CEMRA) and contrast enhanced computer tomography (CECT) of the left atrium and pulmonary veins of 137 health objects and patients with atrial fibrillation (AF) are processed with the technique of post-processing, and Projective Angles to the coronary and transversal sections are measured and analyzed statistically. Result: Project Angles of pulmonary veins are one of real and steady imaging anatomic characteristics of pulmonary veins. The statistical distribution of variables is relatively concentrated, with a fairly good representation of average value. It is possible to improve the angle of the central X-ray according to the average value in the selective angiography of pulmonary veins undergoing the catheter ablation of AF.
Biophysical optimality of the golden angle in phyllotaxis
Okabe, Takuya
2015-10-01
Plant leaves are arranged around a stem axis in a regular pattern characterized by common fractions, a phenomenon known as phyllotaxis or phyllotaxy. As plants grow, these fractions often transition according to simple rules related to Fibonacci sequences. This mathematical regularity originates from leaf primordia at the shoot tip (shoot apical meristem), which successively arise at fixed intervals of a divergence angle, typically the golden angle of 137.5°. Algebraic and numerical interpretations have been proposed to explain the golden angle observed in phyllotaxis. However, it remains unknown whether phyllotaxis has adaptive value, even though two centuries have passed since the phenomenon was discovered. Here, I propose a new adaptive mechanism explaining the presence of the golden angle. This angle is the optimal solution to minimize the energy cost of phyllotaxis transition. This model accounts for not only the high precision of the golden angle but also the occurrences of other angles observed in nature. The model also effectively explains the observed diversity of rational and irrational numbers in phyllotaxis.
High resolution survey for topographic surveying
International Nuclear Information System (INIS)
In this decade, terrestrial laser scanner (TLS) is getting popular in many fields such as reconstruction, monitoring, surveying, as-built of facilities, archaeology, and topographic surveying. This is due the high speed in data collection which is about 50,000 to 1,000,000 three-dimensional (3D) points per second at high accuracy. The main advantage of 3D representation for the data is that it is more approximate to the real world. Therefore, the aim of this paper is to show the use of High-Definition Surveying (HDS), also known as 3D laser scanning for topographic survey. This research investigates the effectiveness of using terrestrial laser scanning system for topographic survey by carrying out field test in Universiti Teknologi Malaysia (UTM), Skudai, Johor. The 3D laser scanner used in this study is a Leica ScanStation C10. Data acquisition was carried out by applying the traversing method. In this study, the result for the topographic survey is under 1st class survey. At the completion of this study, a standard of procedure was proposed for topographic data acquisition using laser scanning systems. This proposed procedure serves as a guideline for users who wish to utilize laser scanning system in topographic survey fully
Application of GPS in a high precision engineering survey network
International Nuclear Information System (INIS)
A GPS satellite survey was carried out with the Macrometer to support construction at the Stanford Linear Accelerator Center (SLAC). The network consists of 16 stations of which 9 stations were part of the Macrometer network. The horizontal and vertical accuracy of the GPS survey is estimated to be 1 to 2 mm and 2 to 3 mm respectively. The horizontal accuracy of the terrestrial survey, consisting of angles and distances, equals that of the GPS survey only in the ''loop'' portion of the network. All stations are part of a precise level network. The ellipsoidal heights obtained from the GPS survey and the orthometric heights of the level network are used to compute geoid undulations. A geoid profile along the linac was computed by the National Geodetic Survey in 1963. This profile agreed with the observed geoid within the standard deviation of the GPS survey. Angles and distances were adjusted together (TERRA), and all terrestrial observations were combined with the GPS vector observations in a combination adjustment (COMB). A comparison of COMB and TERRA revealed systematic errors in the terrestrial solution. A scale factor of 1.5 ppM +- .8 ppM was estimated. This value is of the same magnitude as the over-all horizontal accuracy of both networks. 10 refs., 3 figs., 5 tabs
The FLAMINGOS Extragalactic Survey
Elston, R J; McKenzie, E; Brodwin, M; Brown, M J I; Cardona, G; Dey, A; Dickinson, M; Eisenhardt, P R M; Jannuzi, B T; Lin, Y T; Mohr, J J; Raines, S N; Stanford, S A; Stern, D; Elston, Richard J.; Gonzalez, Anthony H.; Kenzie, Eric Mc; Brodwin, Mark; Brown, Michael J. I.; Cardona, Gustavo; Dey, Arjun; Dickinson, Mark; Eisenhardt, Peter R.; Jannuzi, Buell T.; Lin, Yen-Ting; Mohr, Joseph J.; Stern, Daniel
2006-01-01
Using the Florida Multi-object Imaging Near-IR grism Observational Spectrometer (FLAMINGOS), we have conducted the FLAMINGOS Extragalactic Survey (FLAMEX), a deep imaging survey covering 7.1 square degrees within the 18.6 sq. deg NOAO Deep Wide-Field Survey (NDWFS) regions. FLAMEX is the first deep, wide-area near-infrared survey to image in both the J and Ks filters, and is larger than any previous NIR surveys of comparable depth. The intent of FLAMEX is to facilitate the study of galaxy and galaxy cluster evolution at 11 galaxy clusters detected using the joint FLAMEX, NDWFS, and Spitzer IRAC Shallow Survey data sets.
Bethlehem, Jelke
2011-01-01
BEST PRACTICES TO CREATE AND IMPLEMENTHIGHLY EFFECTIVE WEB SURVEYS Exclusively combining design and sampling issues, Handbook of Web Surveys presents a theoretical yet practical approach to creating and conducting web surveys. From the history of web surveys to various modes of data collection to tips for detecting error, this book thoroughly introduces readers to the this cutting-edge technique and offers tips for creating successful web surveys. The authors provide a history of web surveys and go on to explore the advantages and disadvantages of this mode of dat
Measurement of critical contact angle in a microgravity space experiment
Energy Technology Data Exchange (ETDEWEB)
Concus, P.; Finn, R.; Weislogel, M.
1999-06-01
Mathematical theory predicts that small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. This phenomenon was investigated in the Interface Configuration Experiment on board the NASA USML-2 Space Shuttle flight. The experiment's double proboscis containers were designed to strike a balance between conflicting requirements of sizable volume of liquid shift (for ease of observation) and abruptness of the shift (for accurate determination of critical contact angle). The experimental results support the classical concept of macroscopic contact angle and demonstrate the role of hysteresis in impeding orientation toward equilibrium.
Measurement of critical contact angle in a microgravity space experiment
Energy Technology Data Exchange (ETDEWEB)
Concus, P. [California Univ., Berkeley, CA (United States). Lawrence Berkeley Lab.; Finn, R. [Department of Mathematics, Stanford University, CA (United States); Weislogel, M. [NASA Lewis Research Center, Cleveland, OH (United States)
2000-03-01
Mathematical theory predicts that small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. This phenomenon was investigated in the interface configuration experiment on board the NASA USML-2 Space Shuttle flight. The experiment's ''double proboscis'' containers were designed to strike a balance between conflicting requirements of sizable volume of liquid shift (for ease of observation) and abruptness of the shift (for accurate determination of critical contact angle). The experimental results support the classical concept of macroscopic contact angle and demonstrate the role of hysteresis in impeding orientation toward equilibrium. (orig.)
On unconstrained SU(2)-gluodynamics with θ-angle
International Nuclear Information System (INIS)
The Hamiltonian reduction of classical SU(2) Yang-Mills field theory to the equivalent unconstrained theory of gauge invariant local dynamical variables is generalized to the case of nonvanishing θ-angle. It is shown that for any θ-angle the elimination of the pure gauge degrees of freedom leads to a corresponding unconstrained nonlocal theory of self-interacting second rank symmetric tensor fields, and that the obtained classical unconstrained gluodynamics with different θ-angles are canonically equivalent as on the original constrained level
Angle-action estimation in a general axisymmetric potential
Sanders, Jason
2012-01-01
The usefulness of angle-action variables in galaxy dynamics is well known, but their use is limited due to the difficulty of their calculation in realistic galaxy potentials. Here we present a method for estimating angle-action variables in a realistic Milky Way axisymmetric potential by locally fitting a St\\"ackel potential over the region an orbit probes. The quality of the method is assessed by comparison with other known methods for estimating angle-action variables of a range of disc and...
Research of the Pressure Angle for Whole Cycloidal Gears
Institute of Scientific and Technical Information of China (English)
LIU Ling-tao; WANG Jian-hua
2011-01-01
The working profile of whole cycloidal gear is made up of epicycloid and hypocycloid entirely, according to the theory of meshing of gears and the properties of the cycloid, deals with the derivation of the pressure angle formula for the whole cycloidal gear in theory, and reveals changes of the pressure angle of whole cycloidal gear through examples, finds the application relationships between the pressure angle and other design parameters of the whole cycloidal gear, proves the possibility that the whole cycloidal gear can be used in internal parallel move gear mechanism, also provides theoretic fundament for designing internal parallel move whole cycloidal gear correctly.
Mixing angle of doubly heavy baryons in QCD
International Nuclear Information System (INIS)
We calculate the mixing angles between the spin-1/2, Ξbc-Ξbc′ and Ωbc-Ωbc′ states of doubly heavy baryons within the QCD sum rules method. It is found that the mixing angles are large and have the values φΞbc=16°±5° and φΩbc=18°±6°, respectively. The mixing angles are slightly smaller compared to the predictions of the non-relativistic quark model, φΞbc=25.5° and φΩbc=25.9°.
Drop Size Dependence of the Contact Angle of Nanodroplets
Institute of Scientific and Technical Information of China (English)
GUO Hong-Kai; FANG Hai-Ping
2005-01-01
@@ The contact angle of nanosized non-polarized argon sessile droplets on a solid substrate is studied by using molecular dynamics simulations.It is found that the drop size dependence of the contact angle is sensitive to the interaction between the liquid molecules and solid molecules.The contact angle decreases with the decreasing drop size for larger interaction between the liquid molecules and the solid substrate, and vice versa.This observation is consistent with most of the previous theoretical and experimental results.
Control of Angular Intervals for Angle-Multiplexed Holographic Memory
Kinoshita, Nobuhiro; Muroi, Tetsuhiko; Ishii, Norihiko; Kamijo, Koji; Shimidzu, Naoki
2009-03-01
In angle-multiplexed holographic memory, the full width at half maximum of the Bragg selectivity curves is dependent on the angle formed between the medium and incident laser beams. This indicates the possibility of high density and high multiplexing number by varying the angular intervals between adjacent holograms. We propose an angular interval scheduling for closely stacking holograms into medium even when the angle range is limited. We obtained bit error rates of the order of 10-4 under the following conditions: medium thickness of 1 mm, laser beam wavelength of 532 nm, and angular multiplexing number of 300.
Increasing efficacy of graminicides with a forward angled spray
DEFF Research Database (Denmark)
Jensen, Peter Kryger
2012-01-01
Control of annual grass species with vertically oriented leaves in agricultural crops by application of foliar acting herbicides with conventional hydraulic sprayers can be increased using forward angled nozzles. Changing the spray angle from the normally predominantly vertical spray towards...... efficacy on L. perenne at early growth stages using nozzles with different spray quality, at different driving speeds and in different wind conditions. Similarly graminicide efficacy was increased when nozzles were angled 60° forward controlling A. myosuroides. Experiments investigating control of the two...
The modified Cassie’s equation and contact angle hysteresis
Xu, Xianmin
2012-08-29
In this paper, we derive a modified Cassie\\'s equation for wetting on chemically patterned surfaces from a homogenization approach. The derivation reveals that effective contact angle is a local average of the static contact angle along the contact line which describes all possible equilibrium states including the local minimum of the free energy of the system. The usual Cassie\\'s state which corresponds to the global minimum is only a special case. We then discuss the contact angle hysteresis on chemically patterned surfaces. © 2012 Springer-Verlag.
Wide angle near-field diffraction and Wigner distribution
Almeida, J B
2003-01-01
Free-space propagation can be described as a shearing of the Wigner distribution function in the spatial coordinate; this shearing is linear in paraxial approximation but assumes a more complex shape for wide-angle propagation. Integration in the frequency domain allows the determination of near-field diffraction, leading to the well known Fresnel diffraction when small angles are considered and allowing exact prediction of wide-angle diffraction. The authors use this technique to demonstrate evanescent wave formation and diffraction elimination for very small apertures.
Wellbore Surveying While Drilling Based on Kalman Filtering
Directory of Open Access Journals (Sweden)
Mahmoud ElGizawy
2010-01-01
Full Text Available Problem statement: Oil and gas are global fuels obtained primarily from drilling wells in underground terrestrial reservoirs. Vertical drilling is preferred because of its simplicity and therefore low cost, but subsurface targets can often be procured only by directing the wellbore along predefined non-vertical trajectories. For instance, directional drilling must be employed to reach locations inaccessible to the drilling rig, to side track an existing well (multilateral drilling, or to drill multiple wells from the same offshore platform (horizontal drilling. Approach: A complete knowledge of the wellbore direction and orientation during the drilling process is essential to guarantee proper directional drilling procedure. Results: Thus, besides the conventional drilling assembly, directional drilling operations require sensors to provide azimuth, inclination and toolface angles of the drill. These sensors are part of the Measurement-While-Drilling (MWD tool, which in current technology is installed several feet behind the drill bit. In such systems, values for inclination and toolface angles are determined from accelerometer measurements at predetermined stationary surveying stations; these values are then incorporated with magnetometer measurements to deliver the azimuth angle. Values for inclination and azimuth angles at the current surveying station are combined with those from the previous station to compute the position of the probe. However, there is no accurate information about the wellbore trajectory between survey stations. Additionally, the magnetic field of the magnetometers has deleterious effect on the overall accuracy of surveying measurements. Conclusion: A method to provide continuous information about the wellbore trajectory has been developed in this study. The module developed integrates a Rotary Steerable System (RSS and MWD tool into one drilling probe utilizing Inertial Navigation System (INS technology. This is achieved
SU-E-I-56: Scan Angle Reduction for a Limited-Angle Intrafraction Verification (LIVE) System
International Nuclear Information System (INIS)
Purpose: To develop a novel adaptive reconstruction strategy to further reduce the scanning angle required by the limited-angle intrafraction verification (LIVE) system for intrafraction verification. Methods: LIVE acquires limited angle MV projections from the exit fluence of the arc treatment beam or during gantry rotation between static beams. Orthogonal limited-angle kV projections are also acquired simultaneously to provide additional information. LIVE considers the on-board 4D-CBCT images as a deformation of the prior 4D-CT images, and solves the deformation field based on deformation models and data fidelity constraint. LIVE reaches a checkpoint after a limited-angle scan, and reconstructs 4D-CBCT for intrafraction verification at the checkpoint. In adaptive reconstruction strategy, a larger scanning angle of 30° is used for the first checkpoint, and smaller scanning angles of 15° are used for subsequent checkpoints. The onboard images reconstructed at the previous adjacent checkpoint are used as the prior images for reconstruction at the current checkpoint. As the algorithm only needs to reconstruct the small deformation occurred between adjacent checkpoints, projections from a smaller scan angle provide enough information for the reconstruction. XCAT was used to simulate tumor motion baseline drift of 2mm along sup-inf direction at every subsequent checkpoint, which are 15° apart. Adaptive reconstruction strategy was used to reconstruct the images at each checkpoint using orthogonal 15° kV and MV projections. Results: Results showed that LIVE reconstructed the tumor volumes accurately using orthogonal 15° kV-MV projections. Volume percentage differences (VPDs) were within 5% and center of mass shifts (COMS) were within 1mm for reconstruction at all checkpoints. Conclusion: It's feasible to use an adaptive reconstruction strategy to further reduce the scan angle needed by LIVE to allow faster and more frequent intrafraction verification to minimize the
SURVEY, VICTORIA COUNTY, TEXAS
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Solano County California, hydrographic survey data collected by Harned Surveying and Engineering (HSE). Data collection period January 1, 2011 through March 1, 2011.
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
SURVEY, TUSCALOSAA COUNTY, ALABAMA
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
SURVEY, GLADES COUNTY, FLORIDA
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. Source-FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
SURVEY, NATCHITOCHES PARISH, USA
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
National Oceanic and Atmospheric Administration, Department of Commerce — The standardized NEFSC Sea Scallop Survey began in 1980 and has covered an area from Cape Hatteras to Georges Bank. The survey aims to determine the distribution...
Large Pelagics Intercept Survey
National Oceanic and Atmospheric Administration, Department of Commerce — The Large Pelagics Intercept Survey (LPIS) is a dockside survey of private and charterboat captains who have just completed fishing trips directed at large pelagic...
This survey encompasses a family of health care provider surveys, including information about the facilities that supply health care, the services rendered, and the characteristics of the patients served.
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Patient survey (HCAHPS) - National
U.S. Department of Health & Human Services — The national average for the HCAHPS survey categories. HCAHPS is a national, standardized survey of hospital patients about their experiences during a recent...
Federal Emergency Management Agency, Department of Homeland Security — The field survey data for this coastal study includes a field report that exhibits photos and transect information collected in the field survey phase of the study....
SURVEY, BENTON COUNTY, TENNESSEE
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — The field survey data for this coastal study includes a field report that exhibits photos and transect information collected in the field survey phase of the study....
Federal Emergency Management Agency, Department of Homeland Security — The field survey data for this coastal study includes a field report that exhibits photos and transect information collected in the field survey phase of the study....
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — The field survey data for this coastal study includes a field report that exhibits photos and transect information collected in the field survey phase of the study....
Patient survey (HCAHPS) - State
U.S. Department of Health & Human Services — A list of the state averages for the HCAHPS survey responses. HCAHPS is a national, standardized survey of hospital patients about their experiences during a recent...
Federal Emergency Management Agency, Department of Homeland Security — The field survey data for this coastal study includes a field report that exhibits photos and transect information collected in the field survey phase of the study....
SURVEY, FREMONT COUNTY, COLORADO
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...
U.S. Department of Health & Human Services — Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) Hospital Survey The intent of the HCAHPS initiative is to provide a standardized survey...
Federal Emergency Management Agency, Department of Homeland Security — The field survey data for this coastal study includes a field report that exhibits photos and transect information collected in the field survey phase of the study....
Iowa Intensive Archaeological Survey
Iowa State University GIS Support and Research Facility — This shape file contains intensive level archaeological survey areas for the state of Iowa. All intensive Phase I surveys that are submitted to the State Historic...
U.S. Department of Health & Human Services — CMS is interested in linking MAX files with survey data, including four surveys conducted by the National Center for Health Statistics (NCHS) - the National Health...
National Oceanic and Atmospheric Administration, Department of Commerce — The NGS Survey Control Map provides a map of the US which allows you to find and display geodetic survey control points stored in the database of the National...
Tounsi, R.; Markiewicz, E.; Haugou, G.; Chaari, F.; Zouari, B.
2016-05-01
The combined effect of the loading angle (ψ) and the in-plane orientation angle (β) on the dynamic enhancement of aluminium alloy honeycombs is investigated. Experimental results are analysed on the crushing surfaces (initial peak and average crushing forces). A significant effect of the loading angle is reported. The dynamic enhancement rate depends on the loading angle until a critical loading angle (ψcritical). Beyond, a negative dynamic enhancement rate is observed. Concerning the in-plane orientation angle β effect, it depends on the loading angle ψ under quasi-static conditions. Under dynamic conditions, a significant effect is reported independently of the loading angle ψ. Therefore, the dynamic enhancement rate depends on the combined effects of ψ and β angles. A global analysis of the buckling mechanisms allowed us to explain the combined effect of ψ and β angles on the initial peak force. The collapse mechanisms analysis explain the negative dynamic enhancement rate for large loading angles.
Polarization Position Angle Swings caused by Relativistic Effects
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
Polarization position angle swings of ～ 180° observed in extragalacticradio sources are a regular behavior of variability in polarization. They shouldbe due to some kind of physically regular process. We consider relativistic shocksproducing polarization angle swing events. Two magnetic field configurations (force-free field and homogeneous helical field) are considered to demonstrate the results.It is shown that the properties of polarization angle swings and the relationshipbetween the swings and variations in total and polarized flux density are criticallydependent on the configuration of magnetic field and the dynamical behavior of theshock. In particular, we find that in some cases polarization angle swings can occurwhen the total and polarized flux densities only vary by a very small amount. Theseresults may be useful for understanding the polarization variability with both longand short timescales observed in extragalactic radio sources.
On Ruby's solid angle formula and some of its generalizations
Friot, Samuel
2014-01-01
Using the Mellin-Barnes representation, we show that Ruby's solid angle formula and some of its generalizations may be expressed in a compact way in terms of the Appell F4 and Lauricella Fc functions.
On Ruby's solid angle formula and some of its generalizations
Friot, Samuel
2015-02-01
Using the Mellin-Barnes representation, we show that Ruby's solid angle formula and some of its generalizations may be expressed in a compact way in terms of the Appell F4 and Lauricella FC functions.
Calculation of Triggering Angle of Thyristor Rectifiers with Evolutionary Algorithms
Directory of Open Access Journals (Sweden)
Fahri VATANSEVER
2015-05-01
Full Text Available Rectifier circuits have important role in electrical energy systems. Especially in thyristor rectifiers which have capability of generating multiple voltage level, determining/calculating the optimal trigger angle and applying trigger signal at this angles are among the main process. In this study, desired level of average output voltage according to trigger angles is obtained both classically (mathematically solving of equations and using evolutionary algorithms which are genetic algorithms and differential evolutions. In this way, a software can be used in educational purposes which can calculate optimal trigger angles using both mathematically and heuristically, show results and many properties/parameters of circuit graphically and numerically is developed. Analysis/simulations performed with the designed software indicates that evolutionary algorithms can be used in this field effectively and efficiently.
A solution to the Kelvin wake angle controversy
Darmon, Alexandre; Raphaël, Elie
2014-01-01
Gravity waves generated by an object moving at constant speed at the water surface form a specific pattern commonly known as the Kelvin wake. It was proved by Lord Kelvin that such a wake is delimited by a constant angle = 19.47{\\deg}. However a recent study by Rabaud and Moisy based on the observation of airborne images showed that the wake angle seems to decrease as the Froude number Fr increases, scaling as 1/Fr for large Froude numbers. To explain such observations the authors make the strong hypothesis that an object of size b cannot generate wavelengths larger than b thus leading to unrealistic pressure fields to model the object. With no need of such an assumption, we here analytically show that the angle corresponding to the maximum amplitude of the waves scales as 1/Fr for large Froude numbers whereas the Kelvin angle remains constant for all Fr.
Multi-angle Imaging SpectroRadiometer (MISR)
National Aeronautics and Space Administration — The Multi-angle Imaging SpectroRadiometer (MISR) was successfully launched into sun-synchronous polar orbit aboard Terra, NASA's first Earth Observing System (EOS)...
SMALL ANGLE CRAB COMPENSATION FOR LHC IR UPGRADE
Energy Technology Data Exchange (ETDEWEB)
CALAGA,R.; DORDA, U.; OHMI, D.; OIDE, K.; TOMAS, R.; ZIMMERMANN, F.
2007-06-25
A small angle (< 1 mrad) crab scheme is an attractive option for the LHC luminosity upgrade to recover the geometric luminosity loss from the finite crossing angle [I]. The luminosity loss increases steeply to unacceptable levels as the IP beta function is reduced below its nominal value (see Fig. 1 in Ref. [2]). The crab compensation in the LHC can be accomplished using only two sets of deflecting RF cavities, placed in collision-free straight sections of the LHC to nullify the effective crossing angles at IPI & IP5. We also explore a 400 MHz superconducting cavity design and discuss the pertinent RF challenges. We present IR optics configurations with low-angle crab crossing, study the beam-beam performance and proton-beam emittance growth in the presence of crab compensation, lattice errors, and crab RF noise sources.
Arteriovenous malformation in the cerebellopontine angle presenting as trigeminal neuralgia
Directory of Open Access Journals (Sweden)
Paulo C. Figueiredo
1989-03-01
Full Text Available A case of arteriovenous malformation of the left cerebellopontine angle causing symptoms of ipsilateral trigeminal neuralgia is reported. Pain relief followed microsurgical removal of the malformation. The authors review the literature on the subject.
Plane waveguides with corners in the small angle limit
Dauge, Monique
2012-01-01
The plane waveguides with corners considered here are infinite V-shaped strips with constant thickness. They are parametrized by their sole opening angle. We study the eigenpairs of the Dirichlet Laplacian in such domains when their angle tends to 0. We provide multi-scale asymptotics for eigenpairs associated with the lowest eigenvalues. For this, we investigate the eigenpairs of a one-dimensional model which can be viewed as their Born-Oppenheimer approximation. We also investigate the Dirichlet Laplacian on triangles with sharp angles. The eigenvalue asymptotics involve powers of the cube root of the angle, while the eigenvector asymptotics include simultaneously two scales in the triangular part, and one scale in the straight part of the guides.
Relations between Distorted and Original Angles in STR
Directory of Open Access Journals (Sweden)
Smarandache F
2013-07-01
Full Text Available Using the Oblique-Length Contraction Factor, which is a generalization of Lorentz Contraction Factor, one shows several trigonometric relations between distorted and original angles of a moving object lengths in the Special Theory of Relativity
Asronomical refraction: Computational methods for all zenith angles
Auer, L. H.; Standish, E. M.
2000-01-01
It is shown that the problem of computing astronomical refraction for any value of the zenith angle may be reduced to a simple, nonsingular, numerical quadrature when the proper choice is made for the independent variable of integration.
SMALL ANGLE CRAB COMPENSATION FOR LHC IR UPGRADE
International Nuclear Information System (INIS)
A small angle (< 1 mrad) crab scheme is an attractive option for the LHC luminosity upgrade to recover the geometric luminosity loss from the finite crossing angle [I]. The luminosity loss increases steeply to unacceptable levels as the IP beta function is reduced below its nominal value (see Fig. 1 in Ref. [2]). The crab compensation in the LHC can be accomplished using only two sets of deflecting RF cavities, placed in collision-free straight sections of the LHC to nullify the effective crossing angles at IPI and IP5. We also explore a 400 MHz superconducting cavity design and discuss the pertinent RF challenges. We present IR optics configurations with low-angle crab crossing, study the beam-beam performance and proton-beam emittance growth in the presence of crab compensation, lattice errors, and crab RF noise sources
Gauge groups from brane-anti-brane systems at angles
International Nuclear Information System (INIS)
We discuss a system formed by two pairs of brane-anti-brane that form an arbitrary angle in a plane. We identify the gauge groups from this system which presumably could be used to construct gauge theories. (author)
Gauge groups from brane-anti-brane systems at angles
Energy Technology Data Exchange (ETDEWEB)
Vancea, I.V. [Instituto de Fisica Teorica (IFT), Sao Paulo, SP (Brazil)
2001-07-01
We discuss a system formed by two pairs of brane-anti-brane that form an arbitrary angle in a plane. We identify the gauge groups from this system which presumably could be used to construct gauge theories. (author)
Gauge groups from brane-anti-brane systems at angles
Vancea, I. V.
2001-04-01
We discuss a system formed by two pairs of brane-anti-brane that form an arbitrary angle in a plane. We identify the gauge groups from this system which presumably could be used to construct gauge theories...
First statistics of the isopistonic angle for long baseline interferometry
Ziad, A.; Elhalkouj, T.; Petrov, R. G.; Borgnino, J.; Lazrek, M.; Benkhaldoun, Z.; Martin, F.; Elazhari, Y.
2016-06-01
To reach a suitable limiting magnitude with a multi-aperture interferometer, we need to cophase the different telescopes using a reference source. The latter should be located in the same isopistonic domain as the science source. We developed a direct analytical expression of deducing the isopistonic angle from atmospheric optical parameters as seeing, isoplanatic angle and outer scale. All of these atmospheric turbulence parameters are measured by the Generalized Seeing Monitor (GSM). The first statistics of the isopistonic angle obtained from the GSM data are presented and comparison between the major sites over the world are discussed (La Silla, Cerro Pachon, Paranal, San Pedro, Mt Palomar, Mauna Kea, La Palma, Oukaïmeden, Maydanak, Dome C). Implications of these isopistonic angle statistics on large interferometers cophasing in terms of sky coverage and limiting magnitude are discussed.
Parameterization of ion channeling half-angles and minimum yields
Doyle, Barney L.
2016-03-01
A MS Excel program has been written that calculates ion channeling half-angles and minimum yields in cubic bcc, fcc and diamond lattice crystals. All of the tables and graphs in the three Ion Beam Analysis Handbooks that previously had to be manually looked up and read from were programed into Excel in handy lookup tables, or parameterized, for the case of the graphs, using rather simple exponential functions with different power functions of the arguments. The program then offers an extremely convenient way to calculate axial and planar half-angles, minimum yields, effects on half-angles and minimum yields of amorphous overlayers. The program can calculate these half-angles and minimum yields for axes and [h k l] planes up to (5 5 5). The program is open source and available at
Setting of angles on machine tools speeded by magnetic protractor
Vale, L. B.
1964-01-01
An adjustable protractor facilitates transference of angles to remote machine tools. It has a magnetic base incorporating a beam which can be adjusted until its shadow coincides with an image on the screen of a projector.
Angle Insensitive Color Filters in Transmission Covering the Visible Region
Mao, Kening; Shen, Weidong; Yang, Chenying; Fang, Xu; Yuan, Wenjia; Zhang, Yueguang; Liu, Xu
2016-01-01
Angle insensitive color filter based on Metal-SiOx-Metal structure is proposed in this paper, which can keep the same perceived transmitted color when the incidence angle changes from 0° to 60°, especially for p-polarization light. Various silicon oxide films deposited by reaction magnetron sputtering with a tunable refractive index from 1.97 to 3.84 is introduced to meet the strict angle insensitive resonance conditions. The angle resolved spectral filtering for both p-polarization light and s-polarization light are quite well, which can be attributed to the different physical origins for the high angular tolerance for two polarizations. Finally, the effect of SiOx absorption and Ag thickness on the peak transmittance are analyzed.
Shrinkage and trajectory of the flat jet with inclination angle
Institute of Scientific and Technical Information of China (English)
Shufeng Ye; Yusheng Xie; Hongzhi Guo; Ye Huang; Shantong Jin
2003-01-01
The performance of the flat jet with an inclination angle was investigated by a water model. A mathematical model for theshrinkage and the trajectory of the flat jet with an inclination angle was derived theoretically and verified by experimental data of thewater model. The experimental results indicate that the inclination angle (α) has no influence on the shrinkage of the flat jet, theshrinkage of the flat jet along the width direction decreases with the increasing of the initial velocity at the exit (u0) and the initialthickness of the flat jet (t0). Enough bigger initial exit velocity (u0) and initial thickness can suppress the shrinkage of the flat jetalong the width direction and keep the flat jet stabilized. In addition, the trajectory of the flat jet with an inclination angle is parabolicand must be taking into consideration when to determine the striking distance.
Giovanelli, Riccardo; Haynes, Martha P.
2015-01-01
We review the results of HI line surveys of extragalactic sources in the local Universe. In the last two decades major efforts have been made in establishing on firm statistical grounds the properties of the HI source population, the two most prominent being the HI Parkes All Sky Survey (HIPASS) and the Arecibo Legacy Fast ALFA survey (ALFALFA). We review the choices of technical parameters in the design and optimization of spectro-photometric "blind" HI surveys, which for the first time prod...
Origin of Hinge-Like Mechanism in Single-Layer Black Phosphorus: the Angle-Angle Cross Interaction
Jiang, Jin-Wu
2016-01-01
The single-layer black phosphorus is characteristic for its puckered configuration that possesses the hinge-like mechanism, which leads to the highly anisotropic in-plane Poisson's ratios and the negative out-of-plane Poisson's ratio. We reveal that the hinge-like mechanism can be attributed to the angle-angle cross interaction, which, combined with the bond stretching and angle bending interactions, is able to provide a good description of the mechanical properties in the single-layer black ...
The Use of Horizontal and Vertical Angles in Terrestrial Navigation
Lušić, Zvonimir
2013-01-01
The methods of determining a ship’s position in terrestrial navigation by using vertical and horizontal angles are nowadays rarely used. The reason is the relative complexity of the procedure and the lack of accuracy of some methods. Different methods of using horizontal and vertical angles to obtain the line of position (LOP) will be presented in this paper, as well as the occurring errors and recommendations for use. In this paper, the sextant will be considered a basic...
A spin- and angle-resolving photoelectron spectrometer
International Nuclear Information System (INIS)
A new type of hemispherical electron energy analyzer that permits angle and spin resolved photoelectron spectroscopy has been developed. The analyzer permits standard angle resolved spectra to be recorded with a two-dimensional detector in parallel with spin detection using a mini-Mott polarimeter. General design considerations as well as technical solutions are discussed and test results from the Au(111) surface state are presented.
Wigner Functions for the Pair Angle and Orbital Angular Momentum
Kastrup, H. A.
2016-01-01
The problem of constructing physically and mathematically well-defined Wigner functions for the canonical pair angle and angular momentum is solved. While a key element for the construction of Wigner functions for the planar phase space is the Heisenberg-Weyl group, the corresponding group for the cylindrical phase space is the Euclidean group of the plane and its unitary representations. Here the angle is replaced by the pair (cos,sin) which determines the points on the unit circle uniquely....
Silicone Brushes: Omniphobic Surfaces with Low Sliding Angles.
Wooh, Sanghyuk; Vollmer, Doris
2016-06-01
Losing contact: Omniphobic surfaces can be readily produced by acid-catalyzed graft polycondensation of dimethyldimethoxysilane (PDMS). Droplets show a very small contact angle hysteresis as well as a low sliding angle of only a few degrees. The nm-thick PDMS layer is neither easily washed away nor depleted. This method offers a novel approach towards the preparation of super-liquid-repelling surfaces. PMID:27159802
The correlation between quarter point angle and strong absorption radius
Ma, W H; Mukherjee, S; Wang, Q; Patel, D; Yang, Y Y; Ma, J B; Ma, P; Jin, S L; Bai, Z; Liu, X Q
2016-01-01
The main objective of the present work is to correlate quarter-point angle and nuclear radius or nuclear matter distribution. Various phenomenological formulae with parameters for strong absorption radius Rs are obtained and compared by fitting the experimental data of quarter point angle extracted from nuclear elastic scattering reaction systems. The parameterized formula of Rs related to the isospin and binding energy is recommended, that gives a good reproduction of nuclear matter radii of halo nuclei.
Measurement of the angle of superficial tension by images
Yanez M., Javier; Alonso R., Sergio
2006-02-01
When a liquid is deposited on a surface, this one form a certain angle with respect to the surface, where depending on its value, it will conclude that so hard it is his adhesion with the surface. By means of the analysis of images we looked for to measure this angle of superficial tension. In order to make this measurement, we propose a technique by means of projective transformations and one method of regression to estimation parameters to conic fitting.
Reduction of blade passage tone by angle modulation
Fiagbedzi, Y. A.
1982-05-01
Blade staggering has been used in both centrifugal and axial flow fans to reduce discrete tones. Impeller hub resilience, causing fan torsional oscillations, appears to be equivalent to blade staggering in that both lead to angle modulation of the blade passage sound. By using Jacobi-Anger expansions, the sound reductions resulting from the angle modulation effects of these two equivalent techniques are predicted. Excellent agreement is found with published data.
Nonadiabatic Geometric Angle in Nuclear Magnetic Resonance Connection
Cherbal, Omar; Maamache, Mustapha; Drir, Mahrez
2005-01-01
By using the Grassmannian invariant-angle coherents states approach, the classical analogue of the Aharonov-Anandan nonadiabatic geometrical phase is found for a spin one-half in Nuclear Magnetic Resonance (NMR). In the adiabatic limit, the semi-classical relation between the adiabatic Berry’s phase and Hannay’s angle gives exactly the experimental result observed by Suter et al[12].
Measurement of Strabismic Angle Using the Distance Krimsky Test
Joo, Kwang Sic; Koo, Hyun; Moon, Nam Ju
2013-01-01
Purpose To evaluate the correlation of the distance Krimsky test and the alternate prism cover test (APCT) for the distance deviation in patients with horizontal strabismus. Methods Forty patients with horizontal strabismus (20 esotropia and 20 exotropia) were included in this study. Patients with a variable angle of deviation, vertical angle over 5 prism diopters, impaired binocular vision, or poor cooperation were excluded. We instructed the patient to look a target 6 meters away, and appli...
Vehicle Sideslip Angle Estimation Based on Hybrid Kalman Filter
Li, Jing; Zhang, Jiaxu
2016-01-01
Vehicle sideslip angle is essential for active safety control systems. This paper presents a new hybrid Kalman filter to estimate vehicle sideslip angle based on the 3-DoF nonlinear vehicle dynamic model combined with Magic Formula tire model. The hybrid Kalman filter is realized by combining square-root cubature Kalman filter (SCKF), which has quick convergence and numerical stability, with square-root cubature based receding horizon Kalman FIR filter (SCRHKF), which has robustness against m...
Neoclassical Pitch-Angle Scattering of Runaway Electrons
Liu, Jian; Qin, Hong
2015-01-01
It is discovered that the tokamak field geometry generates a pitch-angle scattering effect for runaway electrons. This neoclassical pitch-angle scattering is much stronger than the collisional scattering and invalidates the gyro-center model for runaway electrons. As a result, the energy limit of runaway electrons is found to be larger than the prediction of the gyro-center model and to depend heavily on the background magnetic field.
Comparison of different passive knee extension torque-angle assessments
International Nuclear Information System (INIS)
Previous studies have used isokinetic dynamometry to assess joint torques and angles during passive extension of the knee, often without reporting upon methodological errors and reliability outcomes. In addition, the reliability of the techniques used to measure passive knee extension torque-angle and the extent to which reliability may be affected by the position of the subjects is also unclear. Therefore, we conducted an analysis of the intra- and inter-session reliability of two methods of assessing passive knee extension: (A) a 2D kinematic analysis coupled to a custom-made device that enabled the direct measurement of resistance to stretch and (B) an isokinetic dynamometer used in two testing positions (with the non-tested thigh either flexed at 45° or in the neutral position). The intra-class correlation coefficients (ICCs) of torque, the slope of the torque-angle curve, and the parameters of the mathematical model that were fit to the torque-angle data for the above conditions were measured in sixteen healthy male subjects (age: 21.4 ± 2.1 yr; BMI: 22.6 ± 3.3 kg m−2; tibial length: 37.4 ± 3.4 cm). The results found were: (1) methods A and B led to distinctly different torque-angle responses; (2) passive torque-angle relationship and stretch tolerance were influenced by the position of the non-tested thigh; and (3) ICCs obtained for torque were higher than for the slope and for the mathematical parameters that were fit to the torque-angle curve. In conclusion, the measurement method that is used and the positioning of subjects can influence the passive knee extension torque-angle outcome. (paper)
Advanced conduction angle control of permanent magnet brushless motor drives
Gan, J.; Chan, CC; Jiang, JZ; Chau, KT
1998-01-01
A novel advanced conduction angle control scheme for permanent magnet brushless motor drives is presented in this paper. The originality of this scheme is to employ the transformer EMF in stator windings to counteract the rotational EMF by controlling the advanced conduction angle when the motor drive operates above the base speed. Hence the constant-power operation region can be extended considerably, even though the current regulator is in saturation. The attractive feature of the proposed ...
Hail ice impact on composite structures at glancing angles
Funai, Sho
2012-01-01
Aircraft structures are susceptible to damage due to high velocity hail ice impact. These impacts can create nonvisible damage in the structure, jeopardizing its structural integrity. Experiments were completed with simulated hail ice (SHI) impacting T800/3900-2 carbon/ epoxy tape laminates and aluminum panels at various angles. The angled impacts were similar to the normal impacts in the failure propagation of ice as well as the size and shape of the delaminations. Experimental failure thres...
DEFF Research Database (Denmark)
Schrøder, Lise; Hvingel, Line Træholt; Hansen, Henning Sten;
2014-01-01
The GIS Readiness Survey 2014 is a follow-up to the corresponding survey that was carried out among public institutions in Denmark in 2009. The present survey thus provides an updated image of status and challenges in relation to the use of spatial information, the construction of the com- mon...
Static and Dynamic Contact Angles of Immersed Ferrofluid Droplets
Chatterjee, Souvick; Bhowmik, Dipanwita; Mukhopadhyay, Achintya; Ganguly, Ranjan
2013-11-01
Ferrofluid plug driven micro-pumps are useful for manipulating micro-volume of liquids by providing remote actuation using a localized magnetic field gradient. Inside a microchannel, the ferrofluid experiences combined actions of different relevant body forces. While the pressure, viscous and magnetic forces can be estimated using established techniques, the surface tension force requires information about the contact angle between the ferrofluid and glass capillary wall. We address this phenomenon through experimental characterization of static and dynamic contact angles of oil based ferrofluid (EFH3) droplets on glass surface immersed in pure or surfacted distilled water. The equilibrium static contact angle is found to significantly reduce in presence of a magnetic field. Dynamic contact angles are measured through high-speed imaging as the ferrofluid droplets slide along an inclined glass surface. Variation of contact angle hysteresis, which falls outside the Hoffmann Tanner equation for this case, is also investigated as a function of contact line velocity. A strong dependence is found between the contact angle hysteresis and the wetting time. Findings of the work is useful for designing ferrofluid plug-driven microfluidic plugs for different lab-on-a-chip applications.
Angle-Resolved Plasmonic Properties of Single Gold Nanorod Dimers
Institute of Scientific and Technical Information of China (English)
Jian Wu; Xuxing Lu; Qiannan Zhu; Junwei Zhao; Qishun Shen; Li Zhan; Weihai Ni
2014-01-01
Through wet-chemical assembly methods, gold nanorods were placed close to each other and formed a dimer with a gap distance*1 nm, and hence degenerated plasmonic dipole modes of individual nanorods coupled together to produce hybridized bonding and antibonding resonance modes. Previous studies using a condenser for illumination result in averaged signals over all excitation angles. By exciting an individual dimer obliquely at different angles, we demonstrate that these two new resonance modes are highly tunable and sensitive to the angle between the excitation polarization and the dimer orientation, which follows cos2u dependence. Moreover, for dimer structures with various structure angles, the resonance wavelengths as well as the refractive index sensitivities were found independent of the structure angle. Cal-culated angle-resolved plasmonic properties are in good agreement with the measurements. The assembled nanostructures investigated here are important for fundamental researches as well as potential applications when they are used as building blocks in plasmon-based optical and optoelectronic devices.
Method for producing angled optical fiber tips in the laboratory
Davenport, John J.; Hickey, Michelle; Phillips, Justin P.; Kyriacou, Panicos A.
2016-02-01
A simple laboratory method is presented for producing optical fibers with tips polished at various angles. Angled optical fiber tips are used in applications such as optical sensing and remote laser surgery, where they can be used to control the angle of light leaving the fiber or direct it to the side. This allows for greater control and allows areas to be reached that otherwise could not. Optical fibers were produced with tip angles of 45 deg using a Perspex mounting block with an aluminum base plate. The dispersion of light leaving the tip was tested using a blue (470 nm) LED. The angle imposed an angular shift on the light diffracting out of the tip of approximately 30 deg. Additionally, some light reflected from the tip surface to diffract at 90 deg through the side of the fiber. These observations are consistent with theory and those seen by other studies, validating the method. The method was simple to perform and does not require advanced manufacturing tools. The method is suitable for producing small quantities of angle-tipped optical fibers for research applications.
Operating experience with main blowers with variable blade angles
Energy Technology Data Exchange (ETDEWEB)
Bogatov, I.V.; Spivak, V.A.
1986-05-01
Efficiency of blowers used for ventilation in underground coal mines in the USSR in many cases is below the statistical efficiency level. Efficiency of 30% of blowers does not exceed 60%. New design of blower blades developed and tested in the USSR is an easy and economic way for increasing blower efficiency. Each blade consists of 2 sections: a stationary section and a section with a variable-incidence angle. The incidence angle depends on local conditions and requirements for ventilation. During performance tests of VTsZ-32 blowers in the PKAA mine an angle of blade incidence of 20 or 30 degrees was used. This guaranteed air pressure of 6,000 Pa and air output of 120 m/sup 3//s. Increased blade incidence angle was used in summer and during periods of increased methane emission. In winter angle of blade incidence was reduced to 10 degrees, blower output ranged from 80 to 90 m/sup 3//s, air pressure declined to 3,800 Pa. Using blower blades with variable-incidence angle reduced energy consumption, ventilation cost and investment.
Hybrid algorithm for rotor angle security assessment in power systems
Directory of Open Access Journals (Sweden)
D. Prasad Wadduwage
2015-08-01
Full Text Available Transient rotor angle stability assessment and oscillatory rotor angle stability assessment subsequent to a contingency are integral components of dynamic security assessment (DSA in power systems. This study proposes a hybrid algorithm to determine whether the post-fault power system is secure due to both transient rotor angle stability and oscillatory rotor angle stability subsequent to a set of known contingencies. The hybrid algorithm first uses a new security measure developed based on the concept of Lyapunov exponents (LEs to determine the transient security of the post-fault power system. Later, the transient secure power swing curves are analysed using an improved Prony algorithm which extracts the dominant oscillatory modes and estimates their damping ratios. The damping ratio is a security measure about the oscillatory security of the post-fault power system subsequent to the contingency. The suitability of the proposed hybrid algorithm for DSA in power systems is illustrated using different contingencies of a 16-generator 68-bus test system and a 50-generator 470-bus test system. The accuracy of the stability conclusions and the acceptable computational burden indicate that the proposed hybrid algorithm is suitable for real-time security assessment with respect to both transient rotor angle stability and oscillatory rotor angle stability under multiple contingencies of the power system.
Jet opening angles and gamma-ray brightness of AGN
Pushkarev, A B; Lister, M L; Savolainen, T
2009-01-01
We have investigated the differences in apparent opening angles between the parsec-scale jets of the active galactic nuclei (AGN) detected by the Fermi Large Area Telescope (LAT) during its first three months of operations and those of non-LAT-detected AGN. We used 15.4 GHz VLBA observations of sources from the 2 cm VLBA MOJAVE program, a subset of which comprise the statistically complete flux density limited MOJAVE sample. We determined the apparent opening angles by analyzing transverse jet profiles from the data in the image plane and by applying a model fitting technique to the data in the (u,v) plane. Both methods provided comparable opening angle estimates. The apparent opening angles of gamma-ray bright blazars are preferentially larger than those of gamma-ray weak sources. At the same time, we have found the two groups to have similar intrinsic opening angle distributions. This suggests that the jets in gamma-ray bright AGN are oriented at preferentially smaller angles to the line of sight resulting ...
Limbus Impact on Off-angle Iris Degradation
Energy Technology Data Exchange (ETDEWEB)
Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Santos-Villalobos, Hector J [ORNL; Thompson, Joseph W [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL
2013-01-01
The accuracy of iris recognition depends on the quality of data capture and is negatively affected by several factors such as angle, occlusion, and dilation. Off-angle iris recognition is a new research focus in biometrics that tries to address several issues including corneal refraction, complex 3D iris texture, and blur. In this paper, we present an additional significant challenge that degrades the performance of the off-angle iris recognition systems, called the limbus effect . The limbus is the region at the border of the cornea where the cornea joins the sclera. The limbus is a semitransparent tissue that occludes a side portion of the iris plane. The amount of occluded iris texture on the side nearest the camera increases as the image acquisition angle increases. Without considering the role of the limbus effect, it is difficult to design an accurate off-angle iris recognition system. To the best of our knowledge, this is the first work that investigates the limbus effect in detail from a biometrics perspective. Based on results from real images and simulated experiments with real iris texture, the limbus effect increases the hamming distance score between frontal and off-angle iris images ranging from 0.05 to 0.2 depending upon the limbus height.
Evolution of the jet opening angle distribution in holographic plasma
Rajagopal, Krishna; van der Schee, Wilke
2016-01-01
We use holography to analyze the evolution of an ensemble of jets, with an initial probability distribution for their energy and opening angle as %for jets in proton-proton (pp) collisions, as they propagate through an expanding cooling droplet of strongly coupled plasma as in heavy ion collisions. We identify two competing effects: (i) each individual jet widens as it propagates; (ii) the opening angle distribution for jets emerging from the plasma within any specified range of energies has been pushed toward smaller angles, comparing to pp jets with the same energies. The second effect arises because small-angle jets suffer less energy loss and because jets with a higher initial energy are less probable in the ensemble. We illustrate both effects in a simple two-parameter model, and find that their consequence in sum is that the opening angle distribution for jets in any range of energies contains fewer narrow and wide jets. Either effect can dominate in the mean opening angle, for not unreasonable values o...
Environmental Survey preliminary report
Energy Technology Data Exchange (ETDEWEB)
1988-04-01
This report presents the preliminary findings from the first phase of the Environmental Survey of the United States Department of Energy (DOE) Sandia National Laboratories conducted August 17 through September 4, 1987. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with Sandia National Laboratories-Albuquerque (SNLA). The Survey covers all environmental media and all areas of environmental regulation. It is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations carried on at SNLA, and interviews with site personnel. 85 refs., 49 figs., 48 tabs.
Johnson, Aylmer
2004-01-01
Plane and Geodetic Surveying blends theory and practice, conventional techniques and GPS, to provide the ideal book for students of surveying.Detailed guidance is given on how and when the principle surveying instruments (theodolites, Total Stations, levels and GPS) should be used. Concepts and formulae needed to convert instrument readings into useful results are explained. Rigorous explanations of the theoretical aspects of surveying are given, while at the same time a wealth of useful advice about conducting a survey in practice is provided. An accompanying least squares adjustment program
Doppler angle correction in the measurement of intrarenal parameters
Directory of Open Access Journals (Sweden)
Mennitt K
2011-03-01
Full Text Available Jing Gao¹, Keith Hentel¹, Qiang Zhu², Teng Ma², George Shih¹, Kevin Mennitt¹, Robert Min¹¹Department of Radiology, New York Presbyterian Hospital, Weill Cornell Medical College, NY, USA; ²Division of Diagnostic Ultrasound, Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, ChinaBackground: The aim of this study was to assess differences in intrarenal artery Doppler parameters measured without and with Doppler angle correction.Methods: We retrospectively reviewed color duplex sonography in 30 normally functioning kidneys (20 native kidneys in 10 subjects and 10 transplanted kidneys in 10 subjects performed between January 26, 2010 and July 26, 2010. There were 10 age-matched men and10 age-matched women (mean 39.8 ± 12.2, range 21–60 years in this study. Depending on whether the Doppler angle was corrected in the spectral Doppler measurement, Doppler parameters including peak systolic velocity (PSV, end-diastolic velocity (EDV, and resistive index (RI measured at the interlobar artery of the kidney were divided into two groups, ie, initial Doppler parameters measured without Doppler angle correction (Group 1 and remeasured Doppler parameters with Doppler angle correction (Group 2. Values for PSV, EDV, and RI measured without Doppler angle correction were compared with those measured with Doppler angle correction, and were analyzed statistically with a paired-samples t-test.Results: There were statistical differences in PSV and EDV at the interlobar artery in the upper, mid, and lower poles of the kidney between Group 1 and Group 2 (all P < 0.001. PSV and EDV in Group 1 were significantly lower than in Group 2. RI in Group 1 was the same as that in Group 2 in the upper, mid, and lower poles of the kidneys.Conclusion: Doppler angle correction plays an important role in the accurate measurement of intrarenal blood flow velocity. The true flow velocity converted from the maximum Doppler velocity shift
Gordon, Jeffry S; McNew, Ryan
2008-12-01
Institutions of higher education are now using Internet-based technology tools to conduct surveys for data collection. Research shows that the type and quality of responses one receives with online surveys are comparable with what one receives in paper-based surveys. Data collection can take place on Web-based surveys, e-mail-based surveys, and personal digital assistants/Smartphone devices. Web surveys can be subscription templates, software packages installed on one's own server, or created from scratch using Web programming development tools. All of these approaches have their advantages and disadvantages. The survey owner must make informed decisions as to the right technology to implement. The correct choice can save hours of work in sorting, organizing, and analyzing data. PMID:18940417
ESO imaging survey: infrared deep public survey
Olsen, L. F.; Miralles, J.-M.; da Costa, L.; Madejsky, R.; Jørgensen, H. E.; Mignano, A.; Arnouts, S.; Benoist, C.; Dietrich, J. P.; Slijkhuis, R.; Zaggia, S.
2006-09-01
This paper is part of the series presenting the final results obtained by the ESO Imaging Survey (EIS) project. It presents new J and Ks data obtained from observations conducted at the ESO 3.5 m New Technology Telescope (NTT) using the SOFI camera. These data were taken as part of the Deep Public Survey (DPS) carried out by the ESO Imaging Survey program, significantly extending the earlier optical/infrared EIS-DEEP survey presented in a previous paper of this series. The DPS-IR survey comprises two observing strategies: shallow Ks observations providing nearly full coverage of pointings with complementary multi-band (in general {UBVRI}) optical data obtained using ESO's wide-field imager (WFI) and deeper J and Ks observations of the central parts of these fields. Currently, the DPS-IR survey provides a coverage of roughly 2.1 square degrees ( 300 SOFI pointings) in Ks with 0.63 square degrees to fainter magnitudes and also covered in J, over three independent regions of the sky. The goal of the present paper is to briefly describe the observations, the data reduction procedures, and to present the final survey products which include fully calibrated pixel-maps and catalogs extracted from them. The astrometric solution with an estimated accuracy of ⪉0.15 arcsec is based on the USNO catalog and limited only by the accuracy of the reference catalog. The final stacked images presented here number 89 and 272, in J and K_s, respectively, the latter reflecting the larger surveyed area. The J and Ks images were taken with a median seeing of 0.77 arcsec and 0.8 arcsec. The images reach a median 5σ limiting magnitude of JAB˜23.06 as measured within an aperture of 2´´, while the corresponding limiting magnitude in KsAB is 21.41 and 22.16 mag for the shallow and deep strategies. Although some spatial variation due to varying observing conditions is observed, overall the observed limiting magnitudes are consistent with those originally proposed. The quality of the data
High Pressure Angle Gears: Comparison to Typical Gear Designs
Handschuh, Robert F.; Zabrajsek, Andrew J.
2010-01-01
A preliminary study has been completed to determine the feasibility of using high-pressure angle gears in aeronautic and space applications. Tests were conducted in the NASA Glenn Research Center (GRC) Spur Gear Test Facility at speeds up to 10,000 rpm and 73 N*m (648 in.*lb) for 3.18, 2.12, and 1.59 module gears (8, 12, and 16 diametral pitch gears), all designed to operate in the same test facility. The 3.18 module (8-diametral pitch), 28 tooth, 20deg pressure angle gears are the GRC baseline test specimen. Also, 2.12 module (12-diametral pitch), 42 tooth, 25deg pressure angle gears were tested. Finally 1.59 module (16-diametral pitch), 56 tooth, 35deg pressure angle gears were tested. The high-pressure angle gears were the most efficient when operated in the high-speed aerospace mode (10,000 rpm, lubricated with a synthetic turbine engine oil), and produced the lowest wear rates when tested with a perfluoroether-based grease. The grease tests were conducted at 150 rpm and 71 N*m (630 in.*lb).
Rotating Shaft Tilt Angle Measurement Using an Inclinometer
Luo, Jun; Wang, Zhiqian; Shen, Chengwu; Wen, Zhuoman; Liu, Shaojin; Cai, Sheng; Li, Jianrong
2015-10-01
This paper describes a novel measurement method to accurately measure the rotating shaft tilt angle of rotating machine for alignment or compensation using a dual-axis inclinometer. A model of the rotating shaft tilt angle measurement is established using a dual-axis inclinometer based on the designed mechanical structure, and the calculation equation between the rotating shaft tilt angle and the inclinometer axes outputs is derived under the condition that the inclinometer axes are perpendicular to the rotating shaft. The reversal measurement method is applied to decrease the effect of inclinometer drifts caused by temperature, to eliminate inclinometer and rotating shaft mechanical error and inclinometer systematic error to attain high measurement accuracy. The uncertainty estimation shows that the accuracy of rotating shaft tilt angle measurement depends mainly on the inclinometer uncertainty and its uncertainty is almost the same as the inclinometer uncertainty in the simulation. The experimental results indicate that measurement time is 4 seconds; the range of rotating shaft tilt angle is 0.002° and its standard deviation is 0.0006° using NS-5/P2 inclinometer, whose precision and resolution are ±0.01° and 0.0005°, respectively.
Automated measurement of diagnostic angles for hip dysplasia
de Raedt, Sepp; Mechlenburg, Inger; Stilling, Maiken; Rømer, Lone; Søballe, Kjeld; de Bruijne, Marleen
2013-03-01
A fully automatic method for measuring diagnostic angles of hip dysplasia is presented. The method consists of the automatic segmentation of CT images and detection of anatomical landmarks on the femur and acetabulum. The standard angles used in the diagnosis of hip dysplasia are subsequently automatically calculated. Previous work in automating the measuring of angles required the manual segmentation or delineation of the articular joint surface. In the current work automatic segmentation is established using graph-cuts with a cost function based on a sheetness score to detect the sheet-like structure of the bone. Anatomical landmarks are subsequently detected using heuristics based on ray-tracing and the distance to the approximated acetabulur joint surface. Standard diagnositic angles are finally calculated and presented for interpretation. Experiments using 26 patients, showed a good agreement with gold standard manual measurements by an expert radiologist as performed in daily practice. The mean difference for the five angles was between -1:1 and 2:0 degrees with a concordance correlation coefficient between 0:87 and 0:93. The standard deviation varied between 2:3 and 4:1 degrees. These values correspond to values found in evaluating interobserver and intraobserver variation for manual measurements. The method can be used in clinical practice to replace the current manual measurements performed by radiologists. In the future, the method will be integrated into an intraoperative surgical guidance system.
Epidemiological characterization of primary open-angle glaucoma
Directory of Open Access Journals (Sweden)
Leonor Rosario Díaz Alfonso
2010-11-01
Full Text Available Background: The primary open-angle glaucoma is a problem for public health all over the world. It is a silent and slowly progressive disease leading to blindness. In most patients this can be prevented if the risk factors leading to the disease are detected in time. Objective: To describe some epidemiological factors of patients with primary open-angle glaucoma. Methods: Clinical, epidemiological, prospective and longitudinal study in patients with primary open-angle glaucoma who attended the glaucoma consultation of the Provincial General University Hospital "Dr. Gustavo Aldereguía Lima" of Cienfuegos, from January to February 2009. The following variables were analyzed: age, sex, family and personal medical history, toxic habits and time of diagnosis of the disease. Results: There was prevalence of primary open-angle glaucoma (87, 5% mostly in females (53, 6% and patients over 61 years old as well as in white skinned patients (52 and 62% respectively. Hypertension was the leading entity referred to as pathological personal and family antecedent (62 and 42% respectively. Glaucoma and myopia predominated as previous eye history. The most frequent toxic habits were the consumption of more than 2 cups of coffee a day (53% and smoking (32%. The largest amount of patients had more than 5 years evolution of the disease. Conclusions: Primary open-angle glaucoma occurred mainly in female patients and those with a history
Analyzing angle crashes at unsignalized intersections using machine learning techniques.
Abdel-Aty, Mohamed; Haleem, Kirolos
2011-01-01
A recently developed machine learning technique, multivariate adaptive regression splines (MARS), is introduced in this study to predict vehicles' angle crashes. MARS has a promising prediction power, and does not suffer from interpretation complexity. Negative Binomial (NB) and MARS models were fitted and compared using extensive data collected on unsignalized intersections in Florida. Two models were estimated for angle crash frequency at 3- and 4-legged unsignalized intersections. Treating crash frequency as a continuous response variable for fitting a MARS model was also examined by considering the natural logarithm of the crash frequency. Finally, combining MARS with another machine learning technique (random forest) was explored and discussed. The fitted NB angle crash models showed several significant factors that contribute to angle crash occurrence at unsignalized intersections such as, traffic volume on the major road, the upstream distance to the nearest signalized intersection, the distance between successive unsignalized intersections, median type on the major approach, percentage of trucks on the major approach, size of the intersection and the geographic location within the state. Based on the mean square prediction error (MSPE) assessment criterion, MARS outperformed the corresponding NB models. Also, using MARS for predicting continuous response variables yielded more favorable results than predicting discrete response variables. The generated MARS models showed the most promising results after screening the covariates using random forest. Based on the results of this study, MARS is recommended as an efficient technique for predicting crashes at unsignalized intersections (angle crashes in this study). PMID:21094345
Numerical study of hub taper angle on podded propeller performance
International Nuclear Information System (INIS)
Presently, the majority of podded propulsion systems are of the pulling type, because this type provides better hydrodynamic efficiency than the pushing type. There are several possible explanations for the better overall performance of a puller type podded propulsor. One is related to the difference in hub shape. Puller and pusher propellers have opposite hub taper angles, hence different hub and blade root shape. These differences cause changes in the flow condition and possibly influence the overall performance. The current study focuses on the variation in performance of pusher and puller propellers with the same blade sections, but different hub taper angles. A hyperboloidal low order source doublet steady/unsteady time domain panel method code was modified and used to evaluate effects of hub taper angle on the open water propulsive performance of some fixed pitch screw propellers used in podded propulsion systems. The modified code was first validated against measurements of two model propellers in terms of average propulsive performance and good agreement was found. Major findings include significant effects of hub taper angle on propulsive performance of tapered hub propellers and noticeable effects of hub taper angle on sectional pressure distributions of tapered hub propeller blades. (author)
Rotational Angle Measurement of Bridge Support Using Image Processing Techniques
Directory of Open Access Journals (Sweden)
Young-Soo Park
2016-01-01
Full Text Available Measuring a very small rotational angle accurately and dynamically is indeed a challenging issue, especially in the case of bridge support. Also, existing inclinometers do not have sufficient resolution and accuracy to measure a bridge’s rotational angle. In this study, a new measurement system was developed to provide a practical means for measuring dynamic rotational angle of a bridge support. It features high resolution and accuracy compared with the available systems on the market. By the combinational use of a laser pointer and a vision-based displacement measurement system, the measurement accuracy was significantly increased. The accuracy and applicability were investigated through laboratory tests. From the laboratory tests, it has been found that the developed system can be applicable to bridge support with very small rotational angle. The effectiveness of the developed system was verified through field tests on real bridges. From the full-scale implementation on two PSC girder bridges, it is observed that the proposed system can measure the rotational angle with a high accuracy and reliability.
Dynamical deformed Airy beams with arbitrary angles between two wings.
Liang, Yi; Hu, Yi; Ye, Zhuoyi; Song, Daohong; Lou, Cibo; Zhang, Xinzheng; Xu, Jingjun; Morandotti, Roberto; Chen, Zhigang
2014-07-01
We study both numerically and experimentally the acceleration and propagation dynamics of 2D Airy beams with arbitrary initial angles between their "two wings." Our results show that the acceleration of these generalized 2D Airy beams strongly depends on the initial angles and cannot be simply described by the vector superposition principle (except for the normal case of a 90° angle). However, as a result of the "Hyperbolic umbilic" catastrophe (a two-layer caustic), the main lobes of these 2D Airy beams still propagate along parabolic trajectories even though they become highly deformed. Under such conditions, the peak intensity (leading energy flow) of the 2D Airy beams cannot be confined along the main lobe, in contrast to the normal 90° case. Instead, it is found that there are two parabolic trajectories describing the beam propagation: one for the main lobe, and the other for the peak intensity. Both trajectories can be readily controlled by varying the initial wing angle. Due to their self-healing property, these beams tend to evolve into the well-known 1D or 2D Airy patterns after a certain propagation distance. The theoretical analysis corroborates our experimental observations, and explains clearly why the acceleration of deformed Airy beams increases with the opening of the initial wing angle. PMID:25121433
Determination of refractive index of various materials on Brewster angle
Tikhonov, Eugene A
2015-01-01
Studied experimentally the origin of the non-zero reflection of p-polarized radiation (TM) of Brewster's angle. The results have shown the residual reflected light in the vicinity of Brewster angle occurs due to inaccessibility 100% polarization degree the incident linearly-polarized radiation and installation of the zero azimuthal angle. These factors create the s-component of the radiation reflected from the examined surface indeed. A smooth change of reflected light polarization in the vicinity of Brewster angle in the sequence p-s-p appears due to the changing power proportion of reflected p-, and s-components but not is the result of the atomically thin transitional layer at the border of the material/environment according to Drude model. Metrological aspects of refractive index measurement by Brewster angle are investigated: due to the above-mentioned factors, as well as due to the contribution of the reflected scattered light caused by on residual roughness of the optical surface. Advantages of Brewste...
Scattering-angle based filtering of the waveform inversion gradients
Alkhalifah, Tariq Ali
2014-11-22
Full waveform inversion (FWI) requires a hierarchical approach to maneuver the complex non-linearity associated with the problem of velocity update. In anisotropic media, the non-linearity becomes far more complex with the potential trade-off between the multiparameter description of the model. A gradient filter helps us in accessing the parts of the gradient that are suitable to combat the potential non-linearity and parameter trade-off. The filter is based on representing the gradient in the time-lag normalized domain, in which the low scattering angle of the gradient update is initially muted out in the FWI implementation, in what we may refer to as a scattering angle continuation process. The result is a low wavelength update dominated by the transmission part of the update gradient. In this case, even 10 Hz data can produce vertically near-zero wavenumber updates suitable for a background correction of the model. Relaxing the filtering at a later stage in the FWI implementation allows for smaller scattering angles to contribute higher-resolution information to the model. The benefits of the extended domain based filtering of the gradient is not only it\\'s ability in providing low wavenumber gradients guided by the scattering angle, but also in its potential to provide gradients free of unphysical energy that may correspond to unrealistic scattering angles.
Citalopram associated with acute angle-closure glaucoma: case report
Directory of Open Access Journals (Sweden)
Hassan Sabit
2005-10-01
Full Text Available Abstract Background Acute angle-closure glaucoma is a rare complication in patients receiving anti-depressant treatment. In the following case, we report the development of acute angle closure glaucoma in a patient who overdosed on Citalopram, an antidepressant, and discuss the possible etiological mechanisms for the condition. Case presentation We report a 54 year old, Caucasian lady, with depression and alcohol dependence syndrome, who developed acute angle-closure glaucoma after an overdose of Citalopram, along with alcohol. She was treated with medications and had bilateral Yag laser iridotomies to correct the glaucoma and has made complete recovery. In this case, the underlying cause for glaucoma appears to be related to the ingestion of Citalopram. Conclusion The patho-physiological basis for acute angle closure glaucoma in relation to antidepressant medications remains unclear. The authors suggest Citalopram may have a direct action on the Iris or Ciliary body muscle through serotonergic or anti-cholinergic mechanisms or both. This case highlights the importance of the awareness of the underlying risks, which may predispose an individual to develop acute angle-closure glaucoma, and reminds the clinicians the significance of history taking and examination of the eye before and after starting anti-depressants. This area needs to be further researched.
Constant-variable flip angles for hyperpolarized media MRI
Deng, He; Zhong, Jianping; Ruan, Weiwei; Chen, Xian; Sun, Xianping; Ye, Chaohui; Liu, Maili; Zhou, Xin
2016-02-01
The longitudinal magnetization of hyperpolarized media, such as hyperpolarized 129Xe, 3He, etc., is nonrenewable. When the MRI data acquisition begins at the k-domain center, a constant flip angle (CFA) results in an image of high signal-to-noise ratio (SNR) but sacrifices the accuracy of spatial information. On the other hand, a variable flip angle (VFA) strategy results in high accuracy but suffers from a low SNR. In this paper, we propose a novel scheme to optimize both the SNR and accuracy, called constant-variable flip angles (CVFA). The proposed scheme suggests that hyperpolarized magnetic resonance signals are firstly acquired through a train of n∗ CFA excitation pulses, followed by a train of N-n∗ VFA excitation pulses. We simulate and optimize the flip angle used in the CFA section, the number of CFA excitation pulses, the number of VFA excitation pulses, and the initial and final variable flip angles adopted in the VFA section. Phantom and in vivo experiments demonstrate the good performance of the CVFA designs and their ability to maintain both high SNR and spatial resolution.
Multi angle view of lung using optical coherence tomography (OCT)
Golabchi, Ali; DiMarzio, Charles A.; Gouldstone, Andrew
2012-03-01
Lung imaging, visualization and measurement of alveolar volume has great importance in determining lung health. However, the heterogeneity of lung tissue complicates this task. In this paper multi angle Optical Coherence Tomography (OCT) is used to overcome this problem. One of the limitations of utilizing OCT in lung is the speckle noise and artifacts that originate from the refraction at the tissue-air interface inside the lung. Multi angle view of lung using OCT is incoherent summation of multiple angle-diverse images. Utilizing image registration of multi angle OCT scans of the lung helps reduce the speckle noise and refraction artifacts. This technique helps extract more information from the images which improves visualization and the ability to measure the geometry of alveoli. The other diculty of utilizing OCT is interpreting the images due to the low numerical aperture (NA) on the OCT. The multi angle view of the lung increases NA, which increase the imaging resolution through synthetic aperture imaging. In this paper in ated excised lung tissue and lung phantom are presented.
Low frequency seabed scattering at low grazing angles.
Zhou, Ji-Xun; Zhang, Xue-Zhen
2012-04-01
Low-frequency (LF) seabed scattering at low grazing angles (LGA) is almost impossible to directly measure in shallow water (SW), except through inversion from reverberation. The energy flux method for SW reverberation is briefly introduced in this paper. The closed-form expressions of reverberation in an isovelocity waveguide, derived from this method, indicate that in the three-halves law range interval multimode/ray sea bottom scattering with different incident and scattering angles in forming the reverberation may equivalently be represented by the bottom backscattering at a single range-dependent angle. This equivalent relationship is used to derive the bottom backscattering strength (BBS) as a function of angle and frequency. The LF&LGA BBS is derived in a frequency band of 200-2500 Hz and in a grazing angle range of 1.1°-14.0° from reverberation measurements at three sites with sandy bottoms. This is based on three previous works: (1) The closed-form expressions of SW reverberation [Zhou, (Chinese) Acta Acustica 5, 86-99 (1980)]; (2) the effective geo-acoustic model of sandy bottoms that follows the Biot model [Zhou et al., J. Acoust. Soc. Am. 125, 2847-2866 (2009)] and (3) A quality database of wideband reverberation level normalized to source level [Zhou and Zhang, IEEE J. Oceanic Eng. 30, 832-842 (2005)]. PMID:22501042
Controlling Compressor Vane Flow Vectoring Angles at Transonic Speeds
Munson, Matthew; Rempfer, Dietmar; Williams, David; Acharya, Mukund
2003-11-01
The ability to control flow separation angles from compressor inlet guide vanes with a Coanda-type actuator is demonstrated using both wind tunnel experiments and finite element simulations. Vectoring angles up to 40 degrees from the uncontrolled baseline state were measured with helium schlieren visualization at transonic Mach numbers ranging from 0.1 to 0.6, and with airfoil chord Reynolds numbers ranging from 89,000 to 710,000. The magnitude of the vectoring angle is shown to depend upon the geometry of the trailing edge, and actuator slot size, and the momentum flux coefficient. Under certain conditions the blowing has no effect on the vectoring angle indicating that the Coanda effect is not present. DNS simulations with the finite element method investigated the effects of geometry changes and external flow. Continuous control of the vectoring angle is demonstrated, which has important implications for application to rotating machinery. The technique is shown to reduce the stall flow coefficient by 15 percent in an axial flow compressor.
Disassembling the Galaxy with angle-action coordinates
McMillan, Paul J
2008-01-01
Angle-action coordinates are used to study the relic of a self-gravitating satellite galaxy that was released on a short-period orbit within the disc of the Galaxy. Satellite stars that lie within 1.5 kpc of the Sun are confined to a grid of patches in action space. As the relic phase-mixes for longer, the patches become smaller and more numerous. These patches can be seen even when the angle-action coordinates of an erroneous Galactic potential are used, but using the wrong potential displaces them. Diagnostic quantities constructed from the angle coordinates both allow the true potential to be identified, and the relic to be dated. Hence when large numbers of solar-neighbourhood stars have full phase-space coordinates, it should be possible to identify members of particular relics from the distribution of stars in an approximate action space, and then the relic's age and the Galactic potential precisely measured using angle coordinates. The availability of angle-action coordinates for arbitrary potentials i...
Numerical study of hub taper angle on podded propeller performance
Energy Technology Data Exchange (ETDEWEB)
Islam, M.F.; Veitch, B.; Bose, N. [Memorial Univ. of Newfoundland, Faculty of Engineering and Applied Science, St. John' s, Newfoundland (Canada)]. E-mail: Mohammed.Islam@nrc-cnrc.gc.ca; Liu, P. [National Research Council of Canada, Inst. for Ocean Technology (IOT), St. John' s, Newfoundland (Canada)
2005-07-01
Presently, the majority of podded propulsion systems are of the pulling type, because this type provides better hydrodynamic efficiency than the pushing type. There are several possible explanations for the better overall performance of a puller type podded propulsor. One is related to the difference in hub shape. Puller and pusher propellers have opposite hub taper angles, hence different hub and blade root shape. These differences cause changes in the flow condition and possibly influence the overall performance. The current study focuses on the variation in performance of pusher and puller propellers with the same blade sections, but different hub taper angles. A hyperboloidal low order source doublet steady/unsteady time domain panel method code was modified and used to evaluate effects of hub taper angle on the open water propulsive performance of some fixed pitch screw propellers used in podded propulsion systems. The modified code was first validated against measurements of two model propellers in terms of average propulsive performance and good agreement was found. Major findings include significant effects of hub taper angle on propulsive performance of tapered hub propellers and noticeable effects of hub taper angle on sectional pressure distributions of tapered hub propeller blades. (author)
Response characteristics of neutron survey instruments
International Nuclear Information System (INIS)
Neutron Laboratory (LN) is an integrant of the National Laboratory of Ionising Radiation Metrology LNMRI/IRD has as one of its attributions the calibration of neutron survey meters used in radioprotection. These instruments are important tools for monitoring doses to individuals in the workplace. They are used routinely to determine the dose rates in areas where persons may be occupationally exposed. Aiming the procedures of the laboratory with the international practicals and contribute so that the country pass to adopt the ambient dose equivalent uniquely for most survey meters, the LN intends to initiate the calibration of all those meters in this new quantity. For this it becomes necessary a study of the response of the survey meters projected for MADE when calibrated in the new quantity, allowing, this way, to define which instrument models the calibration in ambient dose equivalent will be possible. As part of this study were made experimental measurements with radionuclides sources (241AmBe and 252Cf) to test the response instruments characteristics. These neutron sources were used to produce standard fields as recommended by ISO. The most used neutron survey meter model in Brazil was tested and your response energy and angle dependence were analised. (author)
Interstellar Refractive Scintillation and Intraday Polarization Angle Swings
Institute of Scientific and Technical Information of China (English)
Shan-Jie Qian; Xi-Zhen Zhang; A. Kraus
2005-01-01
Intraday polarization angle swings of ～180° observed in two sources (QSO 0917+624 and QSO 1150+812) are discussed in the framework of refractive interstellar scintillation by a continuous interstellar medium. Model-fits to the I-,Q- and U- light curves were made for both sources. It is shown that for the case of 0917+624 both the intraday intensity variations and the polarization angle swing of ～180° could be explained consistently in terms of a four-component model, which comprises one steady and two scintillating polarized components and one further non-polarized scintillating component. The polarization angle swing of ～180° observed in 1150+812, which occurred when the polarized flux density was almost constant, could not be explained in terms of refractive scintillation by a continuous medium and might be due to other mechanisms (e.g., scintillation by interstellar clouds).
Corner detection using arc length-based angle estimator
Zhang, Shizheng; Yang, Dan; Huang, Sheng; Zhang, Xiaohong; Qu, Ying; Tu, Liyun; Ren, Zemin
2015-11-01
We present a corner-detection method named arc length-based angle estimator (AAE). Different from most of the existing approaches, AAE focuses on employing angle detection for finding corners, because angle is an important measure for discrete curvature. AAE provides a new robust solution to the estimation of the K-cosine. In AAE, the K-cosine estimation issue in the x, y space is considered as the problem of the slope estimations in the s, x and s, y spaces, where s is the arc length. Then, weighted least square fitting is employed to address such a slope estimation issue. Experimental results demonstrate that AAE can achieve promising performance in comparison with some recent state-of-the-art approaches under two commonly used evaluation metrics, namely average repeatability and localization error criteria.
Neutrino Mixing Angles in Sequential Dominance to NLO and NNLO
Antusch, S; King, S F
2010-01-01
Neutrinos with hierarchical masses and two large mixing angles may naturally originate from sequential dominance (SD). Within this framework we present analytic expressions for the neutrino mixing angles including the next-to-leading order (NLO) and next-to-next-to-leading order (NNLO) corrections arising from the second lightest and lightest neutrino masses. The analytic results for neutrino mixing angles in SD presented here, including the NLO and NNLO corrections, are applicable to a wide class of models and may provide useful insights when confronting the models with data from high precision neutrino experiments. We also point out that for special cases of SD corresponding to form dominance (FD) the NLO and NNLO corrections both vanish. For example we study tri-bimaximal (TB) mixing via constrained sequential dominance (CSD) which involves only a NNLO correction and tri-bimaximal-reactor (TBR) mixing via partially constrained sequential dominance (PCSD) which involves a NLO correction suppressed by the sm...
Analysis of a Low-Angle Annular Expander Nozzle
Directory of Open Access Journals (Sweden)
Kyll Schomberg
2015-01-01
Full Text Available An experimental and numerical analysis of a low-angle annular expander nozzle is presented to observe the variance in shock structure within the flow field. A RANS-based axisymmetric numerical model was used to evaluate flow characteristics and the model validated using experimental pressure readings and schlieren images. Results were compared with an equivalent converging-diverging nozzle to determine the capability of the wake region in varying the effective area of a low-angle design. Comparison of schlieren images confirmed that shock closure occurred in the expander nozzle, prohibiting the wake region from affecting the area ratio. The findings show that a low angle of deflection is inherently unable to influence the effective area of an annular supersonic nozzle design.
Communicability Angle and the Spatial Efficiency of Networks
Estrada, Ernesto
2014-01-01
We introduce the concept of communicability angle between a pair of nodes in a graph. We provide strong analytical and empirical evidence that the average communicability angle for a given network accounts for its spatial efficiency on the basis of the communications among the nodes in a network. We determine characteristics of the spatial efficiency of more than a hundred real-world complex networks that represent complex systems arising in a diverse set of scenarios. In particular, we find that the communicability angle correlates very well with the experimentally measured the relative packing efficiency of proteins that are represented as residue networks. We finally show how we can modulate the spatial efficiency of a network by tuning the weights of the edges of the networks. This allows us to predict effects of external stresses on the spatial efficiency of a network as well as to design strategies to improve important parameters in real-world complex systems.
Evolution of the Jet Opening Angle Distribution in Holographic Plasma.
Rajagopal, Krishna; Sadofyev, Andrey V; van der Schee, Wilke
2016-05-27
We use holography to analyze the evolution of an ensemble of jets, with an initial probability distribution for their energy and opening angle as in proton-proton (pp) collisions, as they propagate through an expanding cooling droplet of strongly coupled plasma as in heavy ion collisions. We identify two competing effects: (i) each individual jet widens as it propagates and (ii) because wide-angle jets lose more energy, energy loss combined with the steeply falling perturbative spectrum serves to filter wide jets out of the ensemble at any given energy. Even though every jet widens, jets with a given energy can have a smaller mean opening angle after passage through the plasma than jets with that energy would have had in vacuum, as experimental data may indicate. PMID:27284647
Orientation angle and the adhesion of single gecko setae.
Hill, Ginel C; Soto, Daniel R; Peattie, Anne M; Full, Robert J; Kenny, T W
2011-07-01
We investigated the effects of orientation angle on the adhesion of single gecko setae using dual-axis microelectromechanical systems force sensors to simultaneously detect normal and shear force components. Adhesion was highly sensitive to the pitch angle between the substrate and the seta's stalk. Maximum lateral adhesive force was observed with the stalk parallel to the substrate, and adhesion decreased smoothly with increasing pitch. The roll orientation angle only needed to be roughly correct with the spatular tuft of the seta oriented grossly towards the substrate for high adhesion. Also, detailed measurements were made to control for the effect of normal preload forces. Higher normal preload forces caused modest enhancement of the observed lateral adhesive force, provided that adequate contact was made between the seta and the substrate. These results should be useful in the design and manufacture of gecko-inspired synthetic adhesives with anisotropic properties, an area of substantial recent research efforts. PMID:21288955
Flow tilt angles near forest edges - Part 1: Sonic anemometry
DEFF Research Database (Denmark)
Dellwik, Ebba; Mann, Jakob; Larsen, Klaus Steenberg
2010-01-01
-sets. These features of the investigated sonic anemometers make them unsuitable for measuring vertical velocities over highly turbulent forested terrain. By comparing the sonic anemometer results to that of a conically scanning Doppler lidar (Dellwik et al., 2010b), sonic anemometer accuracy for measuring...... mean flow tilt angles was estimated to between 2° and 3°. Use of planar fit algorithms, where the mean vertical velocity is calculated as the difference between the neutral and non-neutral flow, does not solve this problem of low accuracy and is not recommended. Because of the large uncertainties...... caused by flow distortion and vertical alignment, it was only possible to a limited extent to relate sonic anemometer flow tilt angles to upwind forest edges, but the results by the lidar indicated that an internal boundary layer affect flow tilt angles at 21m above the forest. This is in accordance with...
Optimization of sharp and viewing-angle-independent structural color
Hsu, Chia Wei; Johnson, Steven G; Soljačić, Marin
2014-01-01
Structural coloration produces some of the most brilliant colors in nature and has many applications. However, sharp color (narrow frequency response) and wide viewing angle (broad angular response) are competing properties and have not been achieved simultaneously in previous studies. Here, we use numerical optimization to discover geometries where the structural color is sharp, yet the hue, saturation, and brightness all remain the same over broad viewing angles (0-90$^\\circ$) under directional illumination. Our model system consists of dipole scatterers arranged into several rings; interference among the scattered waves is optimized to yield the wavelength-selective and angle-insensitive response. Such designs can be useful for display, painting, and biosensing applications.
Laser transillumination imaging for determining wood defects and grain angle
International Nuclear Information System (INIS)
Wood defects and grain angle correlate strongly with timber strength and grading. In this study a laser transillumination imaging method was developed to determine wood defects and grain angle. The method uses a near infrared laser light source which illuminates a wood sample with a round beam and the image generated by the light transmitted through the sample is captured for further analysis. In basic and flawless wood, the transmitted light pattern is an ellipse and wood defects and grain angle deviation will change the shape, size and location of the ellipse. The method could be used for determining the strength of wood, grading sawn timber, studying finger and glue joints, estimating moisture and differentiating between heartwood and sapwood. (paper)
Pitch Angle Control for Variable Speed Wind Turbines
DEFF Research Database (Denmark)
Chen, Zhe; Zhang, Jianzhong; Cheng, M;
2008-01-01
Pitch angle control is the most common means for adjusting the aerodynamic torque of the wind turbine when wind speed is above rated speed and various controlling variables may be chosen, such as wind speed, generator speed and generator power. As conventional pitch control usually use PI...... controller, the mathematical model of the system should be known well. A fuzzy logic pitch angle controller is developed in this paper, in which it does not need well known about the system and the mean wind speed is used to compensate the non-linear sensitivity. The fuzzy logic control strategy may have...... the potential when the system contains strong non-linearity, such as wind turbulence is strong, or the control objectives include fatigue loads. The design of the fuzzy logic controller and the comparisons with conversional pitch angle control strategies with various controlling variables are carried out...
Determination of the mixing angle between new charmonium states
International Nuclear Information System (INIS)
Using the pictures for X(3872) as a mixture of charmonium and molecular D∗0D0 states; Y(3940) as a mixture of χc0 and D∗D′∗ states, and Y(4260) as a mixture of the tetra-quark state with charmonium states, the corresponding mixing angles are estimated within the QCD sum rules. We find that our predictions for the mixing angles of the X(3872), Y(4260), and Y(3940) states are considerably smaller compared to work in which the mixing angles are estimated from the condition in reproducing the mass of these states. Our conclusion is that the considered pictures for the X(3872), Y(4260), and Y(3940) states are not successful in describing these states
Determination of the mixing angle between new charmonium states
International Nuclear Information System (INIS)
Using the pictures for X(3872) as a mixture of charmonium and molecular D*0D0 states; Y(3940) as a mixture of χc0 and D*D'* states, and Y(4260) as a mixture of the tetra-quark state with charmonium states, the corresponding mixing angles are estimated within the QCD sum rules. We find that our predictions for the mixing angles of the X(3872), Y(4260), and Y(3940) states are considerably smaller compared to work in which the mixing angles are estimated from the condition in reproducing the mass of these states. Our conclusion is that the considered pictures for the X(3872), Y(4260), and Y(3940) states are not successful in describing these states. (orig.)
LONG-TERM MEASUREMENTS OF SUNSPOT MAGNETIC TILT ANGLES
Energy Technology Data Exchange (ETDEWEB)
Li Jing [Department of Earth and Space Sciences, University of California at Los Angeles, Los Angeles, CA 90095-1567 (United States); Ulrich, Roger K., E-mail: jli@igpp.ucla.edu [Department of Physics and Astronomy, University of California at Los Angeles, Los Angeles, CA 90095-1567 (United States)
2012-10-20
Tilt angles of close to 30,600 sunspots are determined using Mount Wilson daily averaged magnetograms taken from 1974 to 2012, and SOHO/MDI magnetograms taken from 1996 to 2010. Within a cycle, more than 90% of sunspots have a normal polarity alignment along the east-west direction following Hale's law. The median tilts increase with increasing latitude (Joy's law) at a rate of {approx}0.{sup 0}5 per degree of latitude. Tilt angles of spots appear largely invariant with respect to time at a given latitude, but they decrease by {approx}0.{sup 0}9 per year on average, a trend that largely reflects Joy's law following the butterfly diagram. We find an asymmetry between the hemispheres in the mean tilt angles. On average, the tilts are greater in the Southern than in the Northern Hemisphere for all latitude zones, and the differences increase with increasing latitude.
LONG-TERM MEASUREMENTS OF SUNSPOT MAGNETIC TILT ANGLES
International Nuclear Information System (INIS)
Tilt angles of close to 30,600 sunspots are determined using Mount Wilson daily averaged magnetograms taken from 1974 to 2012, and SOHO/MDI magnetograms taken from 1996 to 2010. Within a cycle, more than 90% of sunspots have a normal polarity alignment along the east-west direction following Hale's law. The median tilts increase with increasing latitude (Joy's law) at a rate of ∼0.05 per degree of latitude. Tilt angles of spots appear largely invariant with respect to time at a given latitude, but they decrease by ∼0.09 per year on average, a trend that largely reflects Joy's law following the butterfly diagram. We find an asymmetry between the hemispheres in the mean tilt angles. On average, the tilts are greater in the Southern than in the Northern Hemisphere for all latitude zones, and the differences increase with increasing latitude.
Long-Term Measurements of Sunspot Magnetic Tilt Angles
Li, Jing
2012-01-01
Tilt angles of close to 30,600 sunspots are determined using Mount Wilson daily averaged magnetograms taken from 1974 to 2012, and MDI/SoHO magnetograms taken from 1996 to 2010. Within a cycle, more than 90% of sunspots have a normal polarity alignment along the east-west direction following Hale's law. The median tilts increase with increasing latitude (Joy's law) at a rate of ~0.5 degree per degree of latitude. Tilt angles of spots appear largely invariant with respect to time at a given latitude, but they decrease by ~0.9degree per year on average, a trend which largely reflects Joy's law following the butterfly diagram. We find an asymmetry between the hemispheres in the mean tilt angles. On average, the tilts are greater in the southern than in the northern hemisphere for all latitude zones, and the differences increase with increasing latitude.
Large-area wide-angle spectrally selective plasmonic absorber
Wu, Chihhui; Neuner, Burton, III; Shvets, Gennady; John, Jeremy; Milder, Andrew; Zollars, Byron; Savoy, Steve
2011-08-01
A simple metamaterial-based wide-angle plasmonic absorber is introduced, fabricated, and experimentally characterized using angle-resolved infrared spectroscopy. The metamaterials are prepared by nano-imprint lithography, an attractive low-cost technology for making large-area samples. The matching of the metamaterial’s impedance to that of vacuum is responsible for the observed spectrally selective “perfect” absorption of infrared light. The impedance is theoretically calculated in the single-resonance approximation, and the responsible resonance is identified as a short-range surface plasmon. The spectral position of the absorption peak (which is as high as 95%) is experimentally shown to be controlled by the metamaterial’s dimensions. The persistence of “perfect” absorption with variable metamaterial parameters is theoretically explained. The wide-angle nature of the absorber can be utilized for subdiffraction-scale infrared pixels exhibiting spectrally selective absorption/emissivity.
Large-area, wide-angle, spectrally selective plasmonic absorber
Wu, Chihhui; John, Jeremy; Milder, Andrew; Zollars, Byron; Savoy, Steve; Shvets, Gennady
2011-01-01
A simple metamaterial-based wide-angle plasmonic absorber is introduced, fabricated, and experimentally characterized using angle-resolved infrared spectroscopy. The metamaterials are prepared by nano-imprint lithography, an attractive low-cost technology for making large-area samples. The matching of the metamaterial's impedance to that of vacuum is responsible for the observed spectrally selective "perfect" absorption of infrared light. The impedance is theoretically calculated in the single-resonance approximation, and the responsible resonance is identified as a short-range surface plasmon. The spectral position of the absorption peak (which is as high as 95%) is experimentally shown to be controlled by the metamaterial's dimensions. The persistence of "perfect" absorption with variable metamaterial parameters is theoretically explained. The wide-angle nature of the absorber can be utilized for sub-diffraction-scale infrared pixels exhibiting spectrally selective absorption/emissivity.
Contact angles of drops on curved superhydrophobic surfaces.
Viswanadam, Goutham; Chase, George G
2012-02-01
Superhydrophobic surfaces have contact angles that exceed 150 degrees and are known to reduce surface fouling, protect surfaces, and improve liquid-liquid separations. Electrospun sub-micron fiber mats can perform as superhydrophobic surfaces. Superhydrophobic behavior is typically measured on planar surfaces, whereas applications may require curved surfaces. This paper discuses the measurement of water contact angles of fiber mats formed on cylindrical surfaces to create superhydrophobic behavior on curved surfaces. Equations are derived that relate the radius of curvature of spherical and cylindrical surfaces and drop size to the observed contact angle on the curved surfaces. Calculations from the equations agree well with experimental observations on spherical surfaces reported in literature and on cylindrical surfaces created in our lab. PMID:22129634
Determination of the mixing angle between new charmonium states
Energy Technology Data Exchange (ETDEWEB)
Aliev, T.M. [Middle East Technical University, Physics Department, Ankara (Turkey); Institute of Physics, Baku (Azerbaijan); Savci, M. [Middle East Technical University, Physics Department, Ankara (Turkey)
2015-04-01
Using the pictures for X(3872) as a mixture of charmonium and molecular D{sup *0}D{sup 0} states; Y(3940) as a mixture of χ{sub c0} and D{sup *}D{sup '*} states, and Y(4260) as a mixture of the tetra-quark state with charmonium states, the corresponding mixing angles are estimated within the QCD sum rules. We find that our predictions for the mixing angles of the X(3872), Y(4260), and Y(3940) states are considerably smaller compared to work in which the mixing angles are estimated from the condition in reproducing the mass of these states. Our conclusion is that the considered pictures for the X(3872), Y(4260), and Y(3940) states are not successful in describing these states. (orig.)
Determination of the mixing angle between new charmonium states
Energy Technology Data Exchange (ETDEWEB)
Aliev, T. M., E-mail: taliev@metu.edu.tr [Physics Department, Middle East Technical University, 06800, Ankara (Turkey); Institute of Physics, Baku (Azerbaijan); Savcı, M., E-mail: savci@metu.edu.tr [Physics Department, Middle East Technical University, 06800, Ankara (Turkey)
2015-04-28
Using the pictures for X(3872) as a mixture of charmonium and molecular D{sup ∗0}D{sup 0} states; Y(3940) as a mixture of χ{sub c0} and D{sup ∗}D{sup ′∗} states, and Y(4260) as a mixture of the tetra-quark state with charmonium states, the corresponding mixing angles are estimated within the QCD sum rules. We find that our predictions for the mixing angles of the X(3872), Y(4260), and Y(3940) states are considerably smaller compared to work in which the mixing angles are estimated from the condition in reproducing the mass of these states. Our conclusion is that the considered pictures for the X(3872), Y(4260), and Y(3940) states are not successful in describing these states.
High Resolution Quantitative Angle-Scanning Widefield Surface Plasmon Microscopy
Tan, Han-Min; Pechprasarn, Suejit; Zhang, Jing; Pitter, Mark C.; Somekh, Michael G.
2016-02-01
We describe the construction of a prismless widefield surface plasmon microscope; this has been applied to imaging of the interactions of protein and antibodies in aqueous media. The illumination angle of spatially incoherent diffuse laser illumination was controlled with an amplitude spatial light modulator placed in a conjugate back focal plane to allow dynamic control of the illumination angle. Quantitative surface plasmon microscopy images with high spatial resolution were acquired by post-processing a series of images obtained as a function of illumination angle. Experimental results are presented showing spatially and temporally resolved binding of a protein to a ligand. We also show theoretical results calculated by vector diffraction theory that accurately predict the response of the microscope on a spatially varying sample thus allowing proper quantification and interpretation of the experimental results.
Experimental investigation of synthetic aperture flow angle estimation
DEFF Research Database (Denmark)
Oddershede, Niels; Jensen, Jørgen Arendt
2005-01-01
Currently synthetic aperture flow methods can find the correct velocity magnitude, when the flow direction is known. To make a fully automatic system, the direction should also be estimated. Such an approach has been suggested by Jensen (2004) based on a search of the highest cross-correlation as a...... function of velocity and angle. This paper presents an experimental investigation of this velocity angle estimation method based on a set of synthetic aperture flow data measured using our RASMUS experimental ultrasound system. The measurements are performed for flow angles of 60, 75, and 90 deg. with...... respect to the axial direction, and for constant velocities with a peak of 0.1 m/s and 0.2 m/s. The implemented synthetic aperture imaging method uses virtual point sources in front of the transducer, and recursive imaging is used to increase the data rate. A 128 element linear array transducer is used...
Large optical field enhancement for nanotips with large opening angles
Thomas, Sebastian; Lemell, Christoph; Burgdörfer, Joachim; Hommelhoff, Peter
2014-01-01
We theoretically investigate optical near-fields at nanometric tips. We systematically study the dependence of field enhancement on the shape, size, and material of the tip. We confirm a strong dependence of the field enhancement factor on the radius of curvature. In addition, we find a remarkably strong increase of field enhancement with increasing opening angle of the nanotips. For gold and tungsten nanotips in the experimentally relevant parameter range (radius of curvature $\\geq 5\\,$nm at 800 nm laser wavelength), we obtain field enhancement factors of up to ${\\sim}35$ (Au) and ${\\sim}12$ (W) for wide opening angles. We confirm this strong dependence on the opening angle for many other materials studying the dependence of the field enhancement at nanotips on the dielectric response function. For dielectrics, the increase in field enhancement is traced back to the electrostatic force of the induced surface charge at the tip shank. For metals, the plasmonic response strongly increases the field enhancement ...
Raccanelli, Alvise; Jeong, Donghui; Neyrinck, Mark C; Szalay, Alexander S
2016-01-01
We study the parity-odd part (that we shall call Doppler term) of the linear galaxy two-point correlation function that arises from wide-angle, velocity, Doppler lensing and cosmic acceleration effects. As it is important at low redshift and at large angular separations, the Doppler term is usually neglected in the current generation of galaxy surveys. For future wide-angle galaxy surveys such as Euclid, SPHEREx and SKA, however, we show that the Doppler term must be included. The effect of these terms is dominated by the magnification due to relativistic aberration effects and the slope of the galaxy redshift distribution and it generally mimics the effect of the local type primordial non-Gaussianity with the effective nonlinearity parameter $f_{\\rm NL}^{\\rm eff}$ of a few, we show that this would affect forecasts on measurements of $f_{\\rm NL}$ at low-redshift. Our results show that a survey at low redshift with large number density over a wide area of the sky could detect the Doppler term with a signal-to-...
Probing the Dark Side of Gravitational Clustering Weak Lensing Statistics at Large Smoothing Angle
Munshi, D
2002-01-01
The weak lensing surveys have the potential to probe directly the clustering statistics of dark matter in the universe. Recent studies have shown that it is possible to predict analytically the whole probability distribution function (pdf) and the bias associated with the collapsed objects in the highly non-linear regime using the hierarchical ansatz. We extend such studies to the quasi-linear regime where the hierarchical ansatz is replaced by the tree-level perturbative calculations to an arbitrary order. It is shown how the generating function techniques can be coupled with the perturbative calculations to compute the complete pdf and the bias in the quasi-linear regime for the weak-lensing convergence field. We study how these quantities depend on the smoothing angle and the source red-shift in different realistic cosmological scenarios. We show that it is possible to define a reduced convergence whose statistics is similar to underlying 3D mass distribution for small smoothing angle but it resembles proj...
Ergonomic Evaluation of the Angle of Abduction in Laptops Environment
Directory of Open Access Journals (Sweden)
Imtiaz Ali Khan
2016-01-01
Full Text Available Laptops in 21st century are an integral part of every professional in vivid fields. Off late there has been emergence of several ergonomic injuries such as repetitive strain injuries (RSIs due to extensive usage of laptops, which can be closely linked with applied force and postures. This study investigated the effect of various angles of keyboard on the applied force and motor action plus response time while performing five distinct tasks. On the basis of literature two different laptops were selected for performing different tasks. For each case the three levels of platform angle were considered as 0°, 5°, and 10°. Male subjects were selected to perform five distinct tasks for each platform angle for both laptops. The force applied (in milli-volts and the motor action plus response time (milli-seconds were recorded using an oscilloscope. The data collected were analyzed through ANOVA using MINITAB software. The abduction angle with the least mean response time and applied force were considered as the best from ergonomics viewpoint. The ANOVA results showed that the angle of abduction for both laptops (small and large do have significant effect on applied force but not on motor action plus response time. The analysis of results indicate that 10° angle of abduction in case of small laptops should be applied to minimize musculoskeletal disorder and repetitive strain injuries. Research relevance: This work suggests that those responsible for the function and operation of laptops would have to redesign the system to reduce injuries, as far as musculoskeletal disorder, repetitive strain injuries and other related problems are concerned. The present work can be quite useful for the system designers of tomorrow.
Contact Angles and Surface Tension of Germanium-Silicon Melts
Croell, A.; Kaiser, N.; Cobb, S.; Szofran, F. R.; Volz, M.; Rose, M. Franklin (Technical Monitor)
2001-01-01
Precise knowledge of material parameters is more and more important for improving crystal growth processes. Two important parameters are the contact (wetting) angle and the surface tension, determining meniscus shapes and surface-tension driven flows in a variety of methods (Czochralski, EFG, floating-zone, detached Bridgman growth). The sessile drop technique allows the measurement of both parameters simultaneously and has been used to measure the contact angles and the surface tension of Ge(1-x)Si(x) (0 less than or equal to x less than or equal to 1.3) alloys on various substrate materials. Fused quartz, Sapphire, glassy carbon, graphite, SiC, carbon-based aerogel, pyrolytic boron nitride (pBN), AIN, Si3N4, and polycrystalline CVD diamond were used as substrate materials. In addition, the effect of different cleaning procedures and surface treatments on the wetting behavior were investigated. Measurements were performed both under dynamic vacuum and gas atmospheres (argon or forming gas), with temperatures up to 1100 C. In some experiments, the sample was processed for longer times, up to a week, to investigate any changes of the contact angle and/or surface tension due to slow reactions with the substrate. For pure Ge, stable contact angles were found for carbon-based substrates and for pBN, for Ge(1-x)Si(x) only for pBN. The highest wetting angles were found for pBN substrates with angles around 170deg. For the surface tension of Ge, the most reliable values resulted in gamma(T) = (591- 0.077 (T-T(sub m)) 10(exp -3)N/m. The temperature dependence of the surface tension showed similar values for Ge(1-x)Si(x), around -0.08 x 10(exp -3)N/m K, and a compositional dependence of 2.2 x 10(exp -3)N/m at%Si.
Community Affairs Office
2010-01-01
In July 2010, the Federal Reserve Bank of Dallas launched the Community Outlook Survey, a quarterly online survey to assess community and economic development in the Eleventh District of the Federal Reserve System--Texas, northern Louisiana and southern New Mexico. ; This seven-question survey focuses on changes in financial well-being for low- and moderate-income (LMI) populations as well as service providers' capacity to serve the needs of these clients. The Bank uses providers' responses t...
Hidrografske meritve : Hydrographic Surveys
Regina Kolenc
2005-01-01
Hydrographic surveys are required for a wide range of civil works engineering and construction activities. They support construction of hydrotechnical objects (dams, hydro-powerplants etc.), safe navigation, flood control missions and topographic survey of wetlands. All this caused development of various surveying methods through years but despite continuous improvements of technology and software, the hydrographic field of work is still one of great pretension.
Small angle elastic scattering of electrons by noble gas atoms
International Nuclear Information System (INIS)
In this thesis, measurements are carried out to obtain small angle elastic differential cross sections in order to check the validity of Kramers-Kronig dispersion relations for electrons scattered by noble gas atoms. First, total cross sections are obtained for argon, krypton and xenon. Next, a parallel plate electrostatic energy analyser for the simultaneous measurement of doubly differential cross section for small angle electron scattering is described. Also absolute differential cross sections are reported. Finally the forward dispersion relation for electron-helium collisions is dealt with. (Auth.)
The optimal angle of Release in Shot Put
Lenz, Alexander
2010-01-01
We determine the optimal angle of release in shot put. The simplest model - mostly used in textbooks - gives a value of $45^\\circ$, while measurements of top athletes cluster around $37 - 38^\\circ$. Including simply the height of the athlete the theory prediction goes down to about $42^\\circ$ for typical parameters of top athletes. Taking further the correlations of the initial velocity of the shot, the angle of release and the height of release into account we predict values around $37 - 38^\\circ$, which coincide perfectly with the measurements.
Automatic learning-based beam angle selection for thoracic IMRT
Energy Technology Data Exchange (ETDEWEB)
Amit, Guy; Marshall, Andrea [Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9 (Canada); Purdie, Thomas G., E-mail: tom.purdie@rmp.uhn.ca; Jaffray, David A. [Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9 (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3E2 (Canada); Techna Institute, University Health Network, Toronto, Ontario M5G 1P5 (Canada); Levinshtein, Alex [Department of Computer Science, University of Toronto, Toronto, Ontario M5S 3G4 (Canada); Hope, Andrew J.; Lindsay, Patricia [Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3E2 (Canada); Pekar, Vladimir [Philips Healthcare, Markham, Ontario L6C 2S3 (Canada)
2015-04-15
Purpose: The treatment of thoracic cancer using external beam radiation requires an optimal selection of the radiation beam directions to ensure effective coverage of the target volume and to avoid unnecessary treatment of normal healthy tissues. Intensity modulated radiation therapy (IMRT) planning is a lengthy process, which requires the planner to iterate between choosing beam angles, specifying dose–volume objectives and executing IMRT optimization. In thorax treatment planning, where there are no class solutions for beam placement, beam angle selection is performed manually, based on the planner’s clinical experience. The purpose of this work is to propose and study a computationally efficient framework that utilizes machine learning to automatically select treatment beam angles. Such a framework may be helpful for reducing the overall planning workload. Methods: The authors introduce an automated beam selection method, based on learning the relationships between beam angles and anatomical features. Using a large set of clinically approved IMRT plans, a random forest regression algorithm is trained to map a multitude of anatomical features into an individual beam score. An optimization scheme is then built to select and adjust the beam angles, considering the learned interbeam dependencies. The validity and quality of the automatically selected beams evaluated using the manually selected beams from the corresponding clinical plans as the ground truth. Results: The analysis included 149 clinically approved thoracic IMRT plans. For a randomly selected test subset of 27 plans, IMRT plans were generated using automatically selected beams and compared to the clinical plans. The comparison of the predicted and the clinical beam angles demonstrated a good average correspondence between the two (angular distance 16.8° ± 10°, correlation 0.75 ± 0.2). The dose distributions of the semiautomatic and clinical plans were equivalent in terms of primary target volume
Alpha emitters activity measurement using the defined solid angle method
International Nuclear Information System (INIS)
The defined solid angle counting method can reach a very high accuracy, specially for heavy ions as alpha particles emitted by a radioactive source. The activity measurement of such sources with a relative uncertainty of the order of 0.01% is investigated. Such an accuracy is available only under suitable conditions: the radiation emitted by the source must be isotropic and all the particles emitted in the effective solid angle must be detected. The efficiency detection value must be equal to unity and phenomena such as absorption or scattering must be null. It is shown that corrections often become necessary. All parameters which can influence the measurements are studied
Measurement of the CKM angle $\\gamma$ at LHCb
Gersabeck, M
2009-01-01
The precise measurement of the CKM unitarity triangle angle $\\gamma$ is a key goal of the LHCb physics programme. The uncertainty on $\\gamma$, the currently least-well known of the three angles, will be reduced dramatically. Complementary measurements will be made in tree-level processes, and modes where loop diagrams play an important role. The tree-level measurements will cover time-integrated as well as time- dependent measurements in both the $B^0_d$ and the $B^0_s$ sectors. The ensemble of these measurements will provide a powerful test of whether new physics phases contribute to heavy-flavour transitions.
Metamaterials with angle selective emissivity in the near-infrared.
Bossard, Jeremy A; Werner, Douglas H
2013-03-11
Metamaterials have been previously studied for their ability to tailor the dispersive IR emissivity of a surface. Here, we investigate two metamaterial structures based on an electromagnetic band-gap surface and a dielectric resonator array for use as near-IR emitters with custom angle selectivity. A genetic algorithm is successfully employed to optimize the metamaterial structures to have minimum emissivity in the normal direction and high emissivity at custom off-normal angles specified by the designer. Two symmetry conditions are utilized to achieve emissivity patterns that are azimuthally stable or distinct in the two orthogonal plane cuts. PMID:23482092
BIPHASIC TREATMENT OF 2ND CLASS ANGLE ANOMALIES
Directory of Open Access Journals (Sweden)
C. Romanec
2011-09-01
Full Text Available Our approach aims at presenting, based on clinical observations and complementary examinations, the effects of a treatment’s setting up during the mixed dentition period. The objectives include the identification of the optimal time of treatment of II/1, II/2 Angle malocclusions, as well as the therapeutic possibilities for the treatment of 2nd class Angle malocclusion during the period of mixed and permanent dentition. The study is based on data collected from 114 clinical cases (69 girls and 45 boys with an age span between 7 and 18 years.
Broadband wide-angle polarization converter for LCD backlight.
Tsai, Chang-Ching; Wu, Shin-Tson
2008-05-20
A novel polarization converter using reflective metallic gratings and a polarization beam splitter is introduced for LCD backlight illumination. These two optical elements form a polarization rotation resonator. Broadband and high optical efficiency of polarization conversion in the visible region is achieved through the resonance of the refracted light and the surface plasmon wave in metallic surface-relief gratings. For wide-angle illumination, the conversion efficiency with arbitrary incident angle is studied. This device can convert unpolarized light to linear polarization with over 85% efficiency. PMID:18493296
Automatic learning-based beam angle selection for thoracic IMRT
International Nuclear Information System (INIS)
Purpose: The treatment of thoracic cancer using external beam radiation requires an optimal selection of the radiation beam directions to ensure effective coverage of the target volume and to avoid unnecessary treatment of normal healthy tissues. Intensity modulated radiation therapy (IMRT) planning is a lengthy process, which requires the planner to iterate between choosing beam angles, specifying dose–volume objectives and executing IMRT optimization. In thorax treatment planning, where there are no class solutions for beam placement, beam angle selection is performed manually, based on the planner’s clinical experience. The purpose of this work is to propose and study a computationally efficient framework that utilizes machine learning to automatically select treatment beam angles. Such a framework may be helpful for reducing the overall planning workload. Methods: The authors introduce an automated beam selection method, based on learning the relationships between beam angles and anatomical features. Using a large set of clinically approved IMRT plans, a random forest regression algorithm is trained to map a multitude of anatomical features into an individual beam score. An optimization scheme is then built to select and adjust the beam angles, considering the learned interbeam dependencies. The validity and quality of the automatically selected beams evaluated using the manually selected beams from the corresponding clinical plans as the ground truth. Results: The analysis included 149 clinically approved thoracic IMRT plans. For a randomly selected test subset of 27 plans, IMRT plans were generated using automatically selected beams and compared to the clinical plans. The comparison of the predicted and the clinical beam angles demonstrated a good average correspondence between the two (angular distance 16.8° ± 10°, correlation 0.75 ± 0.2). The dose distributions of the semiautomatic and clinical plans were equivalent in terms of primary target volume
Winding angle distributions for two-dimensional collapsing polymers
Narros, Arturo; Owczarek, Aleksander L.; Prellberg, Thomas
2016-01-01
We provide numerical support for a long-standing prediction of universal scaling of winding angle distributions. Simulations of interacting self-avoiding walks show that the winding angle distribution for N-step walks is compatible with the theoretical prediction of a Gaussian with a variance growing asymptotically as C log N, with C = 2 in the swollen phase (previously verified), and C = 24/7 at the θ-point. At low temperatures weaker evidence demonstrates compatibility with the same scaling and a value of C = 4 in the collapsed phase, also as theoretically predicted.
X-ray diffraction at Bragg angles around π/2
International Nuclear Information System (INIS)
X-ray diffraction at Bragg angles around π/2 is studied from the theoretical and experimental points of view. The proposed corrections to the dynamical theory in the θβ ≅ π/2 cases, has been reviewed showing the equivalence between two formalisms leading to a corrected expression for the dependence of the angular parameter y with the angle of incidence. An expression for y valid in the conventional and θ β ≅ π/2 cases has been obtained. A general expression for Bragg law and for energy resolution after a Bragg diffraction was also deduced. (author)
Precise predictions of neutrino mixing angles and $CP$ phase
Abbas, Gauhar
2016-01-01
The neutrino mixing parameters are studied using renormalization-group evolution of Dirac neutrinos with recently proposed parameterization of the neutrino mixing angles referred as `high-scale mixing relations'. The correlations among all neutrino mixing and $CP$ violating parameters are investigated. The predictions for the neutrino mixing angles and the $CP$ phase are precise and could be easily tested by ongoing and future experiments. We observe that the high scale mixing unification hypothesis is incompatible with Dirac neutrinos due to updated experimental data.
Confocal supercritical angle fluorescence microscopy for cell membrane imaging
Sivankutty, Siddharth; Mayet, Céline; Dupuis, Guillaume; Fort, Emmanuel; Lévêque-Fort, Sandrine
2013-01-01
We demonstrate sub-wavelength sectioning on biological samples with a conventional confocal microscope. This optical sectioning is achieved by the phenomenon of supercritical angle fuorescence, wherein only a fluorophore next to the interface of a refractive index discontinuity can emit propagating components of radiation into the so-called forbidden angles. The simplicity of this technique allows it to be integrated with a high numerical aperture confocal scanning microscope by only a simple modi?cation on the detection channel. Confocal-SAF microscopy would be a powerful tool to achieve high resolution surface imaging, especially for membrane imaging in biological samples
Long-Term Measurements of Sunspot Magnetic Tilt Angles
Li, Jing; Ulrich, Roger K.
2012-01-01
Tilt angles of close to 30,600 sunspots are determined using Mount Wilson daily averaged magnetograms taken from 1974 to 2012, and MDI/SoHO magnetograms taken from 1996 to 2010. Within a cycle, more than 90% of sunspots have a normal polarity alignment along the east-west direction following Hale's law. The median tilts increase with increasing latitude (Joy's law) at a rate of ~0.5 degree per degree of latitude. Tilt angles of spots appear largely invariant with respect to time at a given la...
Angle dependence of Andreev scattering at semiconductor-superconductor interfaces
DEFF Research Database (Denmark)
Mortensen, Asger; Flensberg, Karsten; Jauho, Antti-Pekka
1999-01-01
We study the angle dependence of the Andreev scattering at a semiconductor-superconductor interface, generalizing the one-dimensional theory of Blonder, Tinkham, and Klapwijk (BTK),An increase of the momentum parallel to the interface leads to suppression of the probability of Andreev reflection ...... angle of incidence above which only normal reflection exists. For two- and three-dimensional interfaces a lower excess current compared to ballistic transport with perpendicular incidence is found. Thus, the one-dimensional BTK model overestimates the barrier strength for two- and three...
Off-Angle Iris Correction using a Biological Model
Energy Technology Data Exchange (ETDEWEB)
Thompson, Joseph T [ORNL; Santos-Villalobos, Hector J [ORNL; Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL
2013-01-01
This work implements an eye model to simulate corneal refraction effects. Using this model, ray tracing is performed to calculate transforms to remove refractive effects in off-angle iris images when reprojected to a frontal view. The correction process is used as a preprocessing step for off-angle iris images for input to a commercial matcher. With this method, a match score distribution mean improvement of 11.65% for 30 degree images, 44.94% for 40 degree images, and 146.1% improvement for 50 degree images is observed versus match score distributions with unmodi ed images.
Demonstration of angle-dependent Casimir force between corrugations.
Banishev, A A; Wagner, J; Emig, T; Zandi, R; Mohideen, U
2013-06-21
The normal Casimir force between a sinusoidally corrugated gold coated plate and a sphere was measured at various angles between the corrugations using an atomic force microscope. A strong dependence on the orientation angle of the corrugation is found. The measured forces were found to deviate from the proximity force approximation and are in agreement with the theory based on the gradient expansion including correlation effects of geometry and material properties. We analyze the role of temperature. The obtained results open new opportunities for control of the Casimir effect in micromechanical systems. PMID:23829717
Small-angle anisotropies in the CMBR from active sources
Battye, R A
1997-01-01
We consider the effects of photon diffusion on the small-angle microwave background anisotropies due to active source models. We find that fluctuations created just before the time of last scattering allow anisotropy to be created on scales much smaller than allowed by standard Silk damping. Using simple models for string and texture structure functions as examples, we illustrate the differences in the angular power spectrum at scales of order a few arcminutes. In particular, we find that the Doppler peak heights are modified by 10-50% and the small-angle fall-off is power law rather than exponential.
Angle of Arrival Detection with Fifth Order Phase Operators
Khmou, Youssef
2015-01-01
In this paper, a fifth order propagator operators are proposed for estimating the Angles Of Arrival (AOA) of narrowband electromagnetic waves impinging on antenna array when its number of sensors is larger than the number of radiating sources. The array response matrix is partitioned into five linearly dependent phases to construct the noise projector using five different propagators from non diagonal blocks of the spectral matrice of the received data; hence, five different estimators are proposed to estimate the angles of the sources. The simulation results proved the performance of the proposed estimators in the presence of white noise comparatively to high resolution eigen based spectra.
Investigation of Brazed Plate Heat Exchangers With Variable Chevron Angles
Directory of Open Access Journals (Sweden)
S. Muthuraman
2013-08-01
Full Text Available - Experiments to measure the condensation heat transfer coefficient and the pressure drop in brazed plate heat exchangers (BPHEs were performed with the refrigerants R410A and R22. Brazed plate heat exchangers with different chevron angles of 45°, 35°, and 20° were used. Varying the mass flux, the condensation temperature, and the vapor quality of the refrigerant, we measured the condensation heat transfer coefficient and the pressure drops. Both the heat transfer coefficient and the pressure drop increased proportionally with the mass flux and the vapor quality and inversely with the condensation temperature and the chevron angle.
RELATIONSHIP BETWEEN THE SIZE OF PONTOCEREBELLAR ANGLE TUMOR AND AUDIOLOGY
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Objective: To study the relationship between the size ofpontocerebellar angle tumor and audiology.Methods: Retrospective analysis of accoustically evoked brainstem response (ABR) waveforms and pure tone threshold in 27 subjects with tumor of pontocerebellar angle.Results: ABR wave forms and pure tone threshold were significantly affected statistically by the size of tumors,especially those tumor larger than 3 cm in diameter.Conclusion: The primary symptom of the patient was unilateral hearing loss.Early discovery of the lesion is important and ABR is a sensitive tool for early diagnose of the tumor.
Structure and Inclination Angle of the Spiral Galaxy M31
Institute of Scientific and Technical Information of China (English)
MA Jun
2001-01-01
The mathematical form, the symmetry of the spiral structure, and the projection of the galactic disc on the image of the spiral galaxy M31 have been directly studied. It is found that M31 has two symmetric arms, i.e. the pitch angles of the two arms are nearly equal; these are 7.7° and 8.0°, respectively. Using the method proposed in this letter, the inclination angle of the galactic disc ofM31 is also obtained, which is 77.5° and is in good agreement with previously published results.
Triangulations of hyperbolic 3-manifolds admitting strict angle structures
Hodgson, Craig D; Segerman, Henry
2011-01-01
It is conjectured that every cusped hyperbolic 3-manifold has a decomposition into positive volume ideal hyperbolic tetrahedra (a "geometric" triangulation of the manifold). Under a mild homology assumption on the manifold we construct topological ideal triangulations which admit a strict angle structure, which is a necessary condition for the triangulation to be geometric. In particular, every knot or link complement in the 3-sphere has such a triangulation. We also give an example of a triangulation without a strict angle structure, where the obstruction is related to the homology hypothesis, and an example illustrating that the triangulations produced using our methods are not generally geometric.
Analysis and design of wide-angle foveated optical systems
Curatu, George
2009-12-01
The development of compact imaging systems capable of transmitting high-resolution images in real-time while covering a wide field-of-view (FOV) is critical in a variety of military and civilian applications: surveillance, threat detection, target acquisition, tracking, remote operation of unmanned vehicles, etc. Recently, optical foveated imaging using liquid crystal (LC) spatial light modulators (SLM) has received considerable attention as a potential approach to reducing size and complexity in fast wide-angle lenses. The fundamental concept behind optical foveated imaging is reducing the number of elements in a fast wide-angle lens by placing a phase SLM at the pupil stop to dynamically compensate aberrations left uncorrected by the optical design. In the recent years, considerable research and development has been conducted in the field of optical foveated imaging based on the LC SLM technology, and several foveated optical systems (FOS) prototypes have been built. However, most research has been focused so far on the experimental demonstration of the basic concept using off-the-shelf components, without much concern for the practicality or the optical performance of the systems. Published results quantify only the aberration correction capabilities of the FOS, often claiming diffraction-limited performance at the region of interest (ROI). However, these results have continually overlooked diffraction effects on the zero-order efficiency and the image quality. The research work presented in this dissertation covers the methods and results of a detailed theoretical research study on the diffraction analysis, image quality, design, and optimization of fast wide-angle FOSs based on the current transmissive LC SLM technology. The amplitude and phase diffraction effects caused by the pixelated aperture of the SLM are explained and quantified, revealing fundamental limitations imposed by the current transmissive LC SLM technology. As a part of this study, five
Quartz-Enhanced Photoacoustic Spectroscopy with Right-Angle Prism
Yongning Liu; Jun Chang; Jie Lian; Zhaojun Liu; Qiang Wang; Zengguang Qin
2016-01-01
A right-angle prism was used to enhance the acoustic signal of a quartz-enhanced photoacoustic spectroscopy (QEPAS) system. The incident laser beam was parallelly inverted by the right-angle prism and passed through the gap between two tuning fork prongs again to produce another acoustic excitation. Correspondingly, two pairs of rigid metal tubes were used as acoustic resonators with resonance enhancement factors of 16 and 12, respectively. The QEPAS signal was enhanced by a factor of 22.4 co...
Fractal dimension and unscreened angles measured for radial viscous fingering.
Praud, Olivier; Swinney, Harry L
2005-07-01
We have examined fractal patterns formed by the injection of air into oil in a thin (0.127 mm) layer contained between two cylindrical glass plates of 288 mm diameter (a Hele-Shaw cell), for pressure differences in the range 0.25 DLA) clusters. We have also measured the probability distribution of unscreened angles. At late times, the distribution approaches a universal (i.e., forcing and size-independent) asymptotic form that has mean 145 degrees Celsius and standard deviation 36 degrees Celsius. These results indicate that the distribution function for the unscreened angle is an invariant property of the growth process. PMID:16089960
Mathematical simulation of gamma-radiation angle distribution measurements
International Nuclear Information System (INIS)
We developed mathematical model of the facility for gamma-radiation angle distribution measurement and calculated response functions for gamma-radiation intensities. We developed special software for experimental data processing, the 'Shelter' object radiation spectra unfolding and Sphere detector (ShD) angle resolution estimation. Neuronet method using for detection of the radiation directions is given. We developed software based on the neuronet algorithm, that allows obtaining reliable distribution of gamma-sources that make impact on the facility detectors at the measurement point. 10 refs.; 15 figs.; 4 tab
Edge effects in angle-ply composite laminates
Hsu, P. W.; Herakovich, C. T.
1977-01-01
This paper presents the results of a zeroth-order solution for edge effects in angle-ply composite laminates obtained using perturbation techniques and a limiting free body approach. The general solution for edge effects in laminates of arbitrary angle ply is applied to the special case of a (+ or - 45)s graphite/epoxy laminate. Interlaminar stress distributions are obtained as a function of the laminate thickness-to-width ratio and compared to finite difference results. The solution predicts stable, continuous stress distributions, determines finite maximum tensile interlaminar normal stress and provides mathematical evidence for singular interlaminar shear stresses in (+ or - 45) graphite/epoxy laminates.
International Nuclear Information System (INIS)
Aerial gamma spectrometry surveys are the most effective, comprehensive and preferred tool to delimit the large area surface contamination in a radiological emergency either due to a nuclear accident or following a nuclear strike. The airborne survey apart from providing rapid and economical evaluation of ground contamination over large areas due to larger ground clearance and higher speed, is the only technique to overcome difficulties posed by ground surveys of inaccessible region. The aerial survey technique can also be used for searching of lost radioactive sources, tracking of radioactive plume and generation of background data on the Emergency Planning Zone (EPZ) of nuclear installations
Survey of photovoltaic systems
Energy Technology Data Exchange (ETDEWEB)
1979-08-01
In developing this survey of photovoltaic systems, the University of Alabama in Huntsville assembled a task team to perform an extensive telephone survey of all known photovoltaic manufacturers. Three US companies accounted for 77% of the total domestic sales in 1978. They are Solarex Corporation, Solar Power Croporation, and ARCO Solar, Inc. This survey of solar photovoltaic (P/V) manufacturers and suppliers consists of three parts: a catalog of suppliers arranged alphabetically, data sheets on specific products, and typical operating, installation, or maintenance instructions and procedures. This report does not recommend or endorse any company product or information presented within as the results of this survey.
Management Satisfaction Survey
Office of Personnel Management — The Chief Human Capital Officers' Managers' Satisfaction Survey asks managers to rate their perception of workforce planning, interaction with and levels of support...
Hongyan Zhang; Zeyu Yang; Liangpei Zhang; Huanfeng Shen
2014-01-01
Multi-angle remote sensing images are acquired over the same imaging scene from different angles, and share similar but not identical information. It is therefore possible to enhance the spatial resolution of the multi-angle remote sensing images by the super-resolution reconstruction technique. However, different sensor shooting angles lead to different resolutions for each angle image, which affects the effectiveness of the super-resolution reconstruction of the multi-angle images. In vie...
Canavese, Federico; Turcot, Katia; Holveck, Jerôme; Farhoumand, Agnés Dahl; Kaelin, André
2011-01-01
The aim of this study is to describe the radiological changes in rib-vertebral angles (RVAs), rib-vertebral angle differences (RVADs), and rib-vertebral angle ratios (RVARas) in patients with untreated right thoracic adolescent idiopathic scoliosis and to compare with the normal subjects. The concave and convex RVA from T1 to T12, the RVADs and the RVARas were measured on AP digital radiographs of 44 female patients with right convex idiopathic scoliosis and 14 normal females. Patients were divided into three groups: normal subjects (group 1), scoliotic patients with Cobb's angle equal or <30° (group 2) and scoliotic patients with Cobb's angle over 30° (group 3). Overall values (mean ± SD) of the RVAs on the concave side were 90.5° ± 17° in group 1, 90.3° ± 15.8° in group 2 and 88.8° ± 15.4° in group 3. On the convex side, values were 90.0° ± 17.3° in group 1, 86.3° ± 13.7° in group 2 and 80.7° ± 14.4° in group 3. Overall values (mean ± SD) of the RVADs at all levels were 0.5° ± 0.7° in group 1, 4.0° ± 4.8° in group 2 and 8.0° ± 4.0° in group 3. The RVARa values (mean ± SD) at all levels was 1.008° ± 0.012° in group 1, 1.041° ± 0.061° in group 2 and 1.102° ± 0.151° in group 3. RVAD and RVARa values in the scoliotic segment were greater in patients with untreated scoliosis over 30° than in patients with an untreated deformity of <30° or normal subjects. A significant effect between groups was observed for the RVA, RVAD and RVARa variables. Measurement of RVA, RVAD and RVARa should not only be performed at and around the apex of a thoracic spinal deformity, but also extended to the whole thoracic spine. PMID:20811755
The Dark Energy Survey: Prospects for resolved stellar populations
Energy Technology Data Exchange (ETDEWEB)
Rossetto, Bruno M. [Observatorio Nacional, Rio de Janeiro (Brazil); Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Santiago, Basílio X. [Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Instituto de Fisica, Porto Alegre (Brazil); Girardi, Léo [Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Osservatorio Astronomica di Padova-INAF, Padova (Italy); Camargo, Julio I. B. [Observatorio Nacional, Rio de Janeiro (Brazil); Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Balbinot, Eduardo [Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Instituto de Fisica, Porto Alegre (Brazil); da Costa, Luiz N. [Observatorio Nacional, Rio de Janeiro (Brazil); Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Yanny, Brian [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Maia, Marcio A. G. [Observatorio Nacional, Rio de Janeiro (Brazil); Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Makler, Martin [Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro (Brazil); Ogando, Ricardo L. C. [Observatorio Nacional, Rio de Janeiro (Brazil); Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Pellegrini, Paulo S. [Observatorio Nacional, Rio de Janeiro (Brazil); Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Ramos, Beatriz [Observatorio Nacional, Rio de Janeiro (Brazil); Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); de Simoni, Fernando [Observatorio Nacional, Rio de Janeiro (Brazil); Lab. Interinstitucional de e-Astronomia-LIneA, Rio de Janeiro (Brazil); Armstrong, R. [Univ. of Illinois, Urbana, IL (United States); Bertin, E. [Univ. Pierre et Marie Curie, Paris (France); Desai, S. [Univ. of Illinois, Urbana, IL (United States); Kuropatkin, N. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lin, H. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Mohr, J. J. [Max-Planck-Institut fur extraterrestrische Physik, Garching (Germany); Tucker, D. L. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
2011-05-06
Wide angle and deep surveys, regardless of their primary purpose, always sample a large number of stars in the Galaxy and in its satellite system. We here make a forecast of the expected stellar sample resulting from the Dark Energy Survey and the perspectives that it will open for studies of Galactic structure and resolved stellar populations in general. An estimated 1.2 x 10^{8} stars will be sampled in DES grizY filters in the southern equatorial hemisphere. This roughly corresponds to 20% of all DES sources. Most of these stars belong to the stellar thick disk and halo of the Galaxy.
Indian Academy of Sciences (India)
P U Sastry; V K Aswal; A G Wagh
2008-11-01
The morphology of carbon nanofoam samples comprising platinum nanoparticles dispersed in the matrix was characterized by small angle neutron scattering (SANS) and small angle X-ray scattering (SAXS) techniques. Results show that the structure of pores of carbon matrix exhibits a mass (pore) fractal nature and the average radius of the platinum particles is about 2.5 nm. The fractal dimension as well as the size distribution parameters of platinum particles varies markedly with the platinum content and annealing temperature. Transmission electron micrographs of the samples corroborate the SANS and SAXS results.
Contrast-enhanced CISS imaging of cerebellopontine angle tumors
Energy Technology Data Exchange (ETDEWEB)
Tozaki, Mitsuhiro; Toyoda, Keiko; Hata, Yuichi; Fukuda, Yasushi; Fukuda, Kunihiko [Jikei Univ., Tokyo (Japan). School of Medicine; Katano, Shuichi
1999-10-01
Our purpose of this study was to evaluate the clinical usefulness of contrast-enhanced CISS-3DFT MR imaging for the diagnosis of CP angle tumors. CISS-3DFT MR imaging is expected for screening procedure of acoustic schwannoma because of excellent spatial resolution. Recently, we discovered contrast enhancement effect on CISS sequence in spite of heavily T{sub 2}-weighted images. Fourteen patients with CP angle tumors were performed on a 1.0 T MR unit. Transaxial CISS-3DFT MRI was obtained both before and after intravenous injections of Gd-DTPA. Multiplanar reconstructions (MPRs) were performed in all cases. Contrast enhancement effect of CP angle tumors, and the relationship between tumors and the adjacent cranial nerves were evaluated. Contrast enhancement effect of the tumors was present in all cases in spite of heavily T{sub 2}-weighted images of CISS sequences. In the internal auditory canal, relationship between the tumors and the cranial nerves was demonstrated in 6 cases (6/9). In the cerebellopontine cistern, all cases were demonstrated (11/11). Contrast-enhanced CISS-3DFT MR imaging with a good contrast resolution and an excellent spatial resolution is useful for the diagnosis of CP angle tumors. (author)
Ultra Small-Angle Neutron Scattering Study of Porous Glass
International Nuclear Information System (INIS)
Compacts of silica micro-spheres prepared for different times at sintering temperatures of 640 deg. C and 740 deg. C have been studied by Ultra Small-Angle Neutron Scattering (USANS) and Scanning Electron Microscopy (SEM). Stress versus strain measurements display several breakage points related to a range of nearest neighbour coordination around each microsphere.
BOND-ANGLE DISTRIBUTION FUNCTIONS IN METALLIC GLASSES
Hafner, J.
1985-01-01
Bond-angle distribution functions have been calculated for realistic models of metallic glasses. They suggest a defected icosahedral short-range bond-orientational order and a close analogy of the short-range topological order in the amorphous and in the crystalline states.
Improved multistep method for wide-angle beam propagation
Yamauchi, Junji; Shibayama, Jun; Sekiguchi, Minoru; Nakano, Hisamatsu
1996-01-01
To improve a wide-angle beam propagation method using a finite-difference technique, the generalized Douglas scheme for variable coefficients is applied to a multistep method. A truncation error of O(Δx)4 is achieved in the transverse direction. The effectiveness of the present method is demonstrated in the analysis of a tilted step-index slab waveguide.
An Analysis of the Morris Loe Angle Trisection Approximation.
Aslan, Farhad,; And Others
1992-01-01
Presents the Morris Loe Angle Trisection Approximation Method to introduce students to areas of mathematics where approximations are used when exact answers are difficult or impossible to obtain. Examines the accuracy of the method using the laws of sines and cosines and a BASIC computer program that is provided. (MDH)
Tight bounds on angle sums of nonobtuse simplices
Czech Academy of Sciences Publication Activity Database
Brandts, J.; Cihangir, A.; Křížek, Michal
2015-01-01
Roč. 267, 15 September (2015), s. 397-408. ISSN 0096-3003 R&D Projects: GA ČR GA14-02067S Institutional support: RVO:67985840 Keywords : nonobtuse simplex * angle sums * spherical geometry * polar simplex Subject RIV: BA - General Mathematics Impact factor: 1.551, year: 2014 http://www.sciencedirect.com/science/article/pii/S0096300315002155
The Power of Pictures : Vertical Picture Angles in Power Pictures
Giessner, Steffen R.; Ryan, Michelle K.; Schubert, Thomas W.; van Quaquebeke, Niels
2011-01-01
Conventional wisdom suggests that variations in vertical picture angle cause the subject to appear more powerful when depicted from below and less powerful when depicted from above. However, do the media actually use such associations to represent individual differences in power? We argue that the d
Progress in small angle neutron scattering activities in Malaysia
International Nuclear Information System (INIS)
Research activities by use of small angle neutron scattering in Malaysia are briefly reported. Scattered neutron data are displayed in two or three-dimensional isometric view by the data acquisition system. Visual Basic is utilized for data acquisition and MathCad for data processing and analyses. (Y. Kazumata)
Penetrator strength effect in long-rod critical ricochet angle
International Nuclear Information System (INIS)
3D numerical simulations were performed in order to further investigate the role of penetrator strength in the interaction of long-rods and oblique targets. Three distinctive regimes resulting from oblique impact depending on the obliquity, namely simple ricochet, critical ricochet and target perforation, were investigated in detail. Critical ricochet angles were calculated with a full 3D explicit finite element method for various impact velocities and strength of target plates and projectiles. Numerical predictions were compared with existing two-dimensional analytical models and test results. It was predicted that critical ricochet angle increases with decreasing impact velocity and that higher ricochet angles were expected if higher strength target materials are employed. But there are differences between analytical models and 3D numerical simulation results or test results. The causes for these discrepancies are established by numerical simulations which explore the validity of the penetrator strength parameter in the analytical model as a physical entity. As a matter of fact, in this paper we first investigate the role of penetrator dynamic strength using two-dimensional simulation which resulted in different penetrator strengths out of different impact velocities. Next, by applying these amounts for penetrator strength in Rosenberg analytical model the critical ricochet angle is calculated. Finally, a comparison between the present analytical method with the 3D simulation and test results shows that the new analytical approach leads to modified results with respect to Rosenberg ones
Overview of Neutrino Mixing Models and Their Mixing Angle Predictions
Energy Technology Data Exchange (ETDEWEB)
Albright, Carl H.
2009-11-01
An overview of neutrino-mixing models is presented with emphasis on the types of horizontal flavor and vertical family symmetries that have been invoked. Distributions for the mixing angles of many models are displayed. Ways to differentiate among the models and to narrow the list of viable models are discussed.
IMU-Based Joint Angle Measurement for Gait Analysis
Directory of Open Access Journals (Sweden)
Thomas Seel
2014-04-01
Full Text Available This contribution is concerned with joint angle calculation based on inertial measurement data in the context of human motion analysis. Unlike most robotic devices, the human body lacks even surfaces and right angles. Therefore, we focus on methods that avoid assuming certain orientations in which the sensors are mounted with respect to the body segments. After a review of available methods that may cope with this challenge, we present a set of new methods for: (1 joint axis and position identification; and (2 flexion/extension joint angle measurement. In particular, we propose methods that use only gyroscopes and accelerometers and, therefore, do not rely on a homogeneous magnetic field. We provide results from gait trials of a transfemoral amputee in which we compare the inertial measurement unit (IMU-based methods to an optical 3D motion capture system. Unlike most authors, we place the optical markers on anatomical landmarks instead of attaching them to the IMUs. Root mean square errors of the knee flexion/extension angles are found to be less than 1° on the prosthesis and about 3° on the human leg. For the plantar/dorsiflexion of the ankle, both deviations are about 1°.
Systemic antihypertensive medication and incident open-angle glaucoma
Muskens, Rogier P. H. M.; de Voogd, Simone; Wolfs, Roger C. W.; Witteman, Jacqueline C. M.; Hofman, Albert; de Jong, Paulus T. V. M.; Stricker, Bruno H. C.; Jansonius, Nomdo M.
2007-01-01
Purpose: To determine the association between systemic anti hypertensive medication and incident open-angle glaucoma. Design: Prospective population-based cohort study. Participants: The study population consisted of a subset of 3842 participants of the Rotterdam Study for whom data from identical o
Non-linear Flight Dynamics at High Angles of Attack
DEFF Research Database (Denmark)
Granasy, P.; Sørensen, C.B.; Mosekilde, Erik; Thomasson, P.G.
1998-01-01
The methods of nonlinear dynamics are applied to the longitudinal motion of a vectored thrust aircraft, in particular the behavior at high angles of attack. Our model contains analytic nonlinear aerodynamical coefficients based on NASA windtunnel experiments on the F-18 high-alpha research vehicle...
Multiple small-angle neutron scattering studies of anisotropic materials
Allen, A J; Long, G G; Ilavsky, J
2002-01-01
Building on previous work that considered spherical scatterers and randomly oriented spheroidal scatterers, we describe a multiple small-angle neutron scattering (MSANS) analysis for nonrandomly oriented spheroids. We illustrate this with studies of the multi-component void morphologies found in plasma-spray thermal barrier coatings. (orig.)
Method on camouflaged target recognition using the angle of ellipsometry
Zhuansun, Xiao-bo; Wu, Wen-Yuan; Huang, Yan-hua; Li, Zhao-zhao
2015-10-01
Using polarimetric information of the camouflaged target surface to identify camouflage has been a hot research area in camouflage detecting. The main method is to use the difference in the degree of polarization(DOP) between background and target to add the contrast ratio of them. The measurement of the DOP has some requirements on the intensity of reflected radiation. In case of low reflected radiation intensity, the difference in the DOP for different materials is not so distinguishable. In addition, the linear degree of polarization is largely under the effects of detection angle and surface roughness, so it is hard to differentiate the degree of polarization when the targets with similar surface roughness are detected at the same detection angle. By analyzing the elements affecting the reflected electromagnetic radiation amplitudes and phase on the camouflaged target surface, this article makes a research on the polarization character of reflected radiation A method on camouflaged target recognition directly or indirectly by taking the angle of ellipsometry (AOE) imaging under the linear polarized light. The function model of the angle of incidence, complex refractive index and AOE was modeled, then the model was simulated by MATLAB and the results showed it can describe the distribution properties of AOE. A new thought for the approach of identifying camouflaged target recognition by detecting polarimetric information was proposed, and it has a deep theoretical and practical significance in camouflaged target recognition.
Small Angle Neutron Scattering instrument at Malaysian TRIGA reactor
Energy Technology Data Exchange (ETDEWEB)
Shukri Mohd; Razali Kassim; Zal Uyun Mahmood [Malaysian Inst. for Nuclear Technology Research (MINT), Bangi, Kajang (Malaysia); Shahidan Radiman
1998-10-01
The TRIGA MARK II Research reactor at the Malaysian Institute for Nuclear Research (MINT) was commissioned in July 1982. Since then various works have been performed to utilise the neutrons produced from this steady state reactor. One of the project involved the Small Angle Neutron Scattering (SANS). (author)
Progress in small angle neutron scattering activities in Malaysia
International Nuclear Information System (INIS)
The current status of SANS (Small Angle Neutron Scattering facility) activities in Malaysia has been presented. Many works need to be done for system improvement before the system can be confidently used as one of effective quality control tools in materials production and engineering sectors. (author)
Effect of attack angle on flow characteristic of centrifugal fan
Wu, Y.; Dou, H. S.; Wei, Y. K.; Chen, X. P.; Chen, Y. N.; Cao, W. B.
2016-05-01
In this paper, numerical simulation is performed for the performance and internal flow of a centrifugal fan with different operating conditions using steady three-dimensional incompressible Navier-Stokes equations coupled with the RNG k-e turbulent model. The performance curves, the contours of static pressure, total pressure, radial velocity, relative streamlines and turbulence intensity at different attack angles are obtained. The distributions of static pressure and velocity on suction surface and pressure surface in the same impeller channel are compared for various attack angles. The research shows that the efficiency of the centrifugal fan is the highest when the attack angle is 8 degree. The main reason is that the vortex flow in the impeller is reduced, and the jet-wake pattern is weakened at the impeller outlet. The pressure difference between pressure side and suction side is smooth and the amplitude of the total pressure fluctuation is low along the circumferential direction. These phenomena may cause the loss reduced for the attack angle of about 8 degree.
Some imaging strategies in multi-angle spatial compounding
DEFF Research Database (Denmark)
Wilhjelm, Jens E.; Jensen, M. S.; Brandt, T.;
2000-01-01
Multi-angle compound images were generated with four schemes: mean, median, root-mean-square and geometric mean. The in vitro images, based on formalin fixed porcine tissue, were analyzed by visual inspection and by calculation of speckle contrast and contrast between different tissues. The mean...
Symmetry constraints for the emission angle dependence of HBT radii
Heinz, Ulrich W; Lisa, M A; Wiedemann, Urs Achim
2002-01-01
We discuss symmetry constraints on the azimuthal oscillations of two-particle correlation (Hanbury Brown--Twiss interferometry) radii for non-central collisions between equal spherical nuclei. We also propose a new method for correcting in a model-independent way the emission angle dependent correlation function for finite event plane resolution and angular binning effects.
Cloak based on the angle dependent constitutive parameters tensors.
Gurvitz, Egor; Andronaki, Semen; Vozianova, Anna; Khodzitsky, Mikhail
2015-10-01
The transformation optics cloak was proposed for the medium with the angle dependent tensors of permittivity and permeability consisted of the right-handed and left-handed metamaterial media. The cloaking effect was numerically simulated using finite element method in the terahertz frequency range for different wave sources. The impact of cloaking medium thickness on the invisibility effect was demonstrated. PMID:26480088
Cerebellar glioblastoma multiforme presenting as a cerebellopontine angle mass
Directory of Open Access Journals (Sweden)
Anupam Jindal
2006-01-01
Full Text Available Cerebellar glioblastoma multiforme (GBM is a highly malignant brain tumour, which is exceedingly rare and such tumour presenting as cerebellopontine angle (CPA mass is even rarer. We here discuss the case of a 15-year-old girl who had cerebellar GBM presenting as CPA mass that resembled meningioma on CT scan and was managed successfully with minimal problems.
Effect of Air Outlet Angle on Air Distribution Performance Index
Directory of Open Access Journals (Sweden)
Isbeyeh W. Maid
2013-05-01
Full Text Available In this paper a numerical study of velocity and temperature distribution in air conditioned space have been made. The computational model consists of the non-isothermal 3-D turbulent with (k-ε model. The numerical study is made to conduct air distribution in a room air-conditioned space with real interior dimensions (6×4×3m and to analyze the effect of changing angle of grille vanes on the flow pattern, velocity, and temperature distribution in the room under a set of different condition, and under a supply air temperature of 16˚C to examine the final result on air distribution performance index (ADPI.The results show a significant effect within the change of supply air angle, the maximum air distribution performance index (ADPI is 52% when air change per hour (ACH is equal to 10 at 16˚C inlet temperature with angle ( 15˚ down, and the minimum value of (ADPI is 20% when ACH is equal to 15 at 16˚C inlet temperature and angle ( degree.
Angle-dependent bandgap engineering in gated graphene superlattices
García-Cervantes, H.; Gaggero-Sager, L. M.; Sotolongo-Costa, O.; Naumis, G. G.; Rodríguez-Vargas, I.
2016-03-01
Graphene Superlattices (GSs) have attracted a lot of attention due to its peculiar properties as well as its possible technological implications. Among these characteristics we can mention: the extra Dirac points in the dispersion relation and the highly anisotropic propagation of the charge carriers. However, despite the intense research that is carried out in GSs, so far there is no report about the angular dependence of the Transmission Gap (TG) in GSs. Here, we report the dependence of TG as a function of the angle of the incident Dirac electrons in a rather simple Electrostatic GS (EGS). Our results show that the angular dependence of the TG is intricate, since for moderated angles the dependence is parabolic, while for large angles an exponential dependence is registered. We also find that the TG can be modulated from meV to eV, by changing the structural parameters of the GS. These characteristics open the possibility for an angle-dependent bandgap engineering in graphene.
Small-angle neutron scattering in materials science - an introduction
Energy Technology Data Exchange (ETDEWEB)
Fratzl, P. [Vienna Univ., Inst. fuer Materialphysik, Vienna (Austria)
1996-12-31
The basic principles of the application of small-angle neutron scattering to materials research are summarized. The text focusses on the classical methods of data evaluation for isotropic and for anisotropic materials. Some examples of applications to the study of alloys, porous materials, composites and other complex materials are given. (author) 9 figs., 38 refs.
Improving gated cardiac scanning using limited-angle reconstruction technique
International Nuclear Information System (INIS)
Selected phases of the cardiac cycle can be imaged by the method of gated cardiac scanning using whole body scanners. However, since there is no synchronization between the random heart beats and the CT machine, the output will have gaps in the angular coverage of each scan. The missing projections in these gaps result in artifacts in the reconstructed images. In this paper, the technique of limited-angle reconstruction is employed to fill in the missing projections to remove the artifacts. The object is transformed back and forth between the object space and the projection space, being corrected in each step by the constraints of the finite spatial extent and of the upper and lower bounds of the object in the object space, and the known projections in the projection space. It is found that by using the proposed algorithm the rms errors of the limited-angle images are reduced to a level comparable to those of the complete-angle images. The same iteration algorithm can also be used to reduce the fan beam scanning angle from 360 degree to 180 degree without sacrificing much image quality
Deformation effects in the heavy ion quarter-point angle
International Nuclear Information System (INIS)
The effects of static and dynamic deformation on the heavy-ion elastic scattering quarter-point angle are discussed and analyzed in the sudden approximation. Simple expressions are derived within the Fresnel model and applications to several heavy-ion systems are presented. (Author)
Progress Report of Small Angle Neutron Scattering on CARR
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
The project of small angle neutron scattering spectrometer (SANS) belongs to "building up the center for neutron scattering". It's one of the project "national science & technology infrastructure center". The building parts are already done in 2010. By the proposal one of
Angle-resolved diffraction grating biosensor based on porous silicon
Lv, Changwu; Jia, Zhenhong; Liu, Yajun; Mo, Jiaqing; Li, Peng; Lv, Xiaoyi
2016-03-01
In this study, an optical biosensor based on a porous silicon composite structure was fabricated using a simple method. This structure consists of a thin, porous silicon surface diffraction grating and a one-dimensional porous silicon photonic crystal. An angle-resolved diffraction efficiency spectrum was obtained by measuring the diffraction efficiency at a range of incident angles. The angle-resolved diffraction efficiency of the 2nd and 3rd orders was studied experimentally and theoretically. The device was sensitive to the change of refractive index in the presence of a biomolecule indicated by the shift of the diffraction efficiency spectrum. The sensitivity of this sensor was investigated through use of an 8 base pair antifreeze protein DNA hybridization. The shifts of the angle-resolved diffraction efficiency spectrum showed a relationship with the change of the refractive index, and the detection limit of the biosensor reached 41.7 nM. This optical device is highly sensitive, inexpensive, and simple to fabricate. Using shifts in diffraction efficiency spectrum to detect biological molecules has not yet been explored, so this study establishes a foundation for future work.
Non-linear Flight Dynamics at High Angles of Attack
DEFF Research Database (Denmark)
Granasy, P.; Sørensen, C.B.; Mosekilde, Erik;
1998-01-01
The methods of nonlinear dynamics are applied to the longitudinal motion of a vectored thrust aircraft, in particular the behavior at high angles of attack. Our model contains analytic nonlinear aerodynamical coefficients based on NASA windtunnel experiments on the F-18 high-alpha research vehicl...
Reflectivity Model of Low Grazing Angle Radar Sea Clutter
Institute of Scientific and Technical Information of China (English)
FENG Sheng; CHEN Jie; CAI Tao; TU Xu-yan
2005-01-01
The commonly used reflectivity models of radar sea clutter are summarized. Among these models, the adjusted Barton model and the adjusted Morchin model are compared. From the analysis result, the γ-p reflectivity model is presented for low grazing angle radar sea clutter by the adjustment of the original Barton reflectivity model. The model takes into account radar frequency, grazing angle, sea condition, and polarization property. The influences of these factors on the proposed model are analyzed. The model absorbs the merits from commonly used reflectivity models for sea clutter. It introduces several researchers' opinions, and extends them. And it accounts for the reflectivity at arbitrary radar frequency from VHF to X-band, arbitrary low grazing angle, arbitrary sea condition and different polarization property. One of the main results is the proposed γ-p reflectivity model can reflect the influence of polarization on sea clutter reflectivity to some extent. The proposed γ-p reflectivity model of low-angle radar-sea clutter is validated by comparing the simulated and statistically experimental data.
A national facility for small angle neutron scattering
International Nuclear Information System (INIS)
A world-class small angle neutron scattering (SANS) facility is proposed for Canada. It will provide users from the fields of biology, chemistry, physics, materials science and engineering with a uniquely powerful tool for investigating microstructural properties whose length scales lie in the optical to atomic range. (author). 7 refs
Small angle X-ray scattering from hydrating tricalcium silicate
International Nuclear Information System (INIS)
The small-angle X-ray scattering technique was used to study the structural evolution of hydrated tricalcium silicate at room temperature. The changes in specific area of the associated porosity and the evolution of density fluctuations in the solid hydrated phase were deduced from the scattering data. A correlation of these variations with the hydration mechanism is tried. (Author)
Installation of NA62 Large Angle Veto detectors
2012-01-01
In May 2012, the NA62 collaboration has installed the first eight (out of 12) Large Angle Veto detectors for the accurate identification of photons. These subdetectors will re-use 3000 lead glass crystals with attached photomultipliers from the OPAL experiment at LEP – CERN’s former accelerator.
Evolution in opening angle combining DGLAP and BFKL logarithms
de Oliveira, E. G.; Martin, A. D.(Institute for Particle Physics Phenomenology, University of Durham, DH1 3LE, Durham, UK); Ryskin, M. G.
2014-01-01
We present an evolution equation which simultaneously sums the leading BFKL and DGLAP logarithms for the integrated gluon distribution in terms of a single variable, namely the emission angle of the gluon. This form of evolution is appropriate for Monte Carlo simulations of events of high energy pp (and p\\bar{p}) interactions, particularly where small x events are sampled.
Evolution in opening angle combining DGLAP and BFKL logarithms
Energy Technology Data Exchange (ETDEWEB)
Oliveira, E.G. de [Universidade Federal de Santa Catarina, Departamento de Fisica, CFM, C.P. 476, Florianopolis, SC (Brazil); Martin, A.D. [University of Durham, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Ryskin, M.G. [University of Durham, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, St. Petersburg (Russian Federation)
2014-10-15
We present an evolution equation which simultaneously sums the leading BFKL and DGLAP logarithms for the integrated gluon distribution in terms of a single variable, namely the emission angle of the gluon. This form of evolution is appropriate for Monte Carlo simulations of events of high energy pp (and p anti p) interactions, particularly where small x events are sampled. (orig.)
Disassembling the Galaxy with angle-action coordinates
McMillan, Paul J.; Binney, James J.
2008-10-01
Angle-action coordinates are used to study the relic of an N-body simulation of a self-gravitating satellite galaxy that was released on a short-period orbit within the disc of the Galaxy. Satellite stars that lie within 1.5kpc of the Sun are confined to a grid of patches in action space. As the relic phase mixes for longer, the patches become smaller and more numerous. These patches can be seen even when the angle-action coordinates of an erroneous Galactic potential are used, but using the wrong potential displaces them. Diagnostic quantities constructed from the angle coordinates both allow the true potential to be identified, and the relic to be dated. Hence, when the full phase space coordinates of large numbers of solar-neighbourhood stars are known, it should be possible to identify members of particular relics from the distribution of stars in an approximate action space. This would then open up the possibility of determining the time since the relic was disrupted and gaining better knowledge of the Galactic potential. The availability of angle-action coordinates for arbitrary potentials is the key to these developments. The paper includes a brief introduction to the torus technique used to generate them.
Drop shape visualization and contact angle measurement on curved surfaces.
Guilizzoni, Manfredo
2011-12-01
The shape and contact angles of drops on curved surfaces is experimentally investigated. Image processing, spline fitting and numerical integration are used to extract the drop contour in a number of cross-sections. The three-dimensional surfaces which describe the surface-air and drop-air interfaces can be visualized and a simple procedure to determine the equilibrium contact angle starting from measurements on curved surfaces is proposed. Contact angles on flat surfaces serve as a reference term and a procedure to measure them is proposed. Such procedure is not as accurate as the axisymmetric drop shape analysis algorithms, but it has the advantage of requiring only a side view of the drop-surface couple and no further information. It can therefore be used also for fluids with unknown surface tension and there is no need to measure the drop volume. Examples of application of the proposed techniques for distilled water drops on gemstones confirm that they can be useful for drop shape analysis and contact angle measurement on three-dimensional sculptured surfaces. PMID:21889152
Combined surgical management of mandibular angle prominence and microgenia
International Nuclear Information System (INIS)
Chin play a very important role in facial aesthetics. Different deformities of volume and of position may occur at this level and it is the microgenia one of the more frequent. Treatment options include the use of silicone, alloplasty materials and autologous bone graft. Authors report the use of the bone removed from mandibular angle to increase the chin. This is the case of a white female patient aged 18 seen by the Orthognathics Multidisciplinary Staff of 'V. I. Lenin' Hospital due to its uncommon face width. The corresponding physical examination as well as the complementary ones diagnosed a bilateral prominence of mandibular angle associated with a microgenia. Surgery carried out was of remodeling type of both mandibular angles and genioplasty of height increase and a discrete advancement using the bone removed from the gonion. There were satisfactory aesthetic results without evidence of bone reabsorption. We conclude that use of autologous graft of mandibular angle is an effective treatment alternative for correction of microgenia. (author)
An Indian perspective on primary angle closure and glaucoma
Directory of Open Access Journals (Sweden)
Sihota Ramanjit
2011-12-01
Full Text Available Aim: To provide a synopsis of primary angle closure disease in India, and Indian studies on the same. Results: Primary angle closure glaucoma forms almost half of all adult primary glaucomas seen in a hospital setting in India. Anatomically, corneal diameters and anterior chamber depths were least in acute and chronic PACG eyes as compared to subacute eyes and controls. Besides relative pupillary block, a Valsalva maneuver during activities of daily living may be responsible for intermittent angle closure and raised IOP in predisposed eyes. Iridotomy alone, controlled the intraocular pressure in 66.7% of subacute eyes and 12.9% of the acute. Medical therapy was additionally required for 35.5% of the acute eyes, 12.1% of the subacute and 30.0% of the chronic cases. There was a greater mean and peak IOP reduction, achieved with 0.005% latanoprost once daily, 8.2 ± 2.0 mm Hg, compared with 0.5% timolol twice daily, 6.1 ± 1.7 mm Hg2. A progression of PACS to PAC was seen in 22%, PAC to PAC OHT in 38.7% and PAC OHT to PACG in 30.7% over 5 years. Conclusions: Primary angle closure disease is common in India, and can be managed well with iridotomy, followed by an appropriate control of IOP.
Neutron imaging and small angle neutron scattering instruments at KUR
International Nuclear Information System (INIS)
We review the neutron imaging (NI) and small-angle neutron scattering (SANS) instruments at KUR, Kumatori, Osaka, Japan. There are two NI and one SANS instruments. The both instruments are compact and used flexibly. Some challenging experiments taking advantage of low neutron fluence are described. The feature of KUR is also described briefly. (author)