CHARACTERIZATION OF POWDER FLOWABILITY USING MEASUREMENT OF ANGLE OF REPOSE
Institute of Scientific and Technical Information of China (English)
D.; Geldart; E.; C.; Abdullah; A.; Hassanpour; L.; C.; Nwoke; I.; Wouters
2006-01-01
In response to the need in industry for a quick and reproducible method of measuring the flowability of powders in processes involving transport and storage, the apparently simple idea of measuring angle of repose has been revived. The simple tester first used has evolved over a number of years into the present version which is shown to be capable of handling quite small samples of powders that are even slightly cohesive. Experimental data are presented and results shown to compare consistently with the better known Hausner ratio.
Experimental study on the angle of repose of pulverized coal
Institute of Scientific and Technical Information of China (English)
Wei Wang; Jiansheng Zhang; Shi Yang; Hai Zhang; Hairui Yang; Guangxi Yue
2010-01-01
An experimental study on the angle of repose(AoR)of pulverized coal with different particle sizes and different moisture contents(MC)was conducted.Three different measurement methods,free-base piling,fixed-base piling and sliding,were used.The data were analyzed by one-way and two-way analysis of variance.The results showed that the AoRs of pulverized coal with particle sizes smaller than 150 μm were in the range of 30-50°.The characterization of the flowability of pulverized coal was some cohesiveness or true cohesiveness.The increase of MC will increase AoR and thus decrease the flowability of the powder.However,the particle size effect is bifurcated.Below a critical size,the decrease of particle size decreases the flowability; while above the critical size,the decrease of particle size increases the flowability.It was found that the value of the critical size strongly depends on the powder density.Moreover,the AoR dependence on particle size could be linked with the Geldart's particle classification.The critical size at the turning point is on the boundary between Group A and Group B in Geldart's classification diagram.Based on the experimental results,there is no significant cross interaction between particle size and MC.The AoRs measured by free-base method and fixed-base method are close,but both remarkably smaller than that measured by the sliding method.
Nonuniformities in the Angle of Repose and Packing Fraction of Large Heaps of Particles
Topić, Nikola; Gallas, Jason A. C.; Pöschel, Thorsten
2012-09-01
We report a numerical investigation of the structural properties of very large three-dimensional heaps of particles produced by ballistic deposition from extended circular dropping areas. Very large heaps are found to contain three new geometrical characteristics not observed before: they may have two external angles of repose, an internal angle of repose, and four distinct packing fraction (density) regions. Such characteristics are shown to be directly correlated with the size of the dropping zone. In addition, we also describe how noise during the deposition affects the final heap structure.
Institute of Scientific and Technical Information of China (English)
刘凡一; 张舰; 李博; 陈军
2016-01-01
In this study, we determined the parameters of wheat required in discrete element method (DEM) simulation by the response surface method. The repose angle is a macroscopic parameter, which is used to describe the friction and flow properties of particle material and widely applied in DEM parameter calibration for it can be measured easily. In this research, the heap of wheat was formed through the bottomless cylinder method and the repose angle was measured using a computer graphic technology. The calibration tests were conducted in laboratory and by simulation using EDEM 2.7.0 software. According to previous research, an acrylic cylinder with an inner diameter of 39 mm and a height of 120 mm was used. The wheat particles were filled into the cylinder using the "rainy method" through a square-opening sieve with 12 mm aperture and lifted with a speed of 0.05 m/s. For DEM simulation, different parameter combination tests were designed. Specifically, the Plackett-Burman test was performed to screen the significant parameters from the 8 selected parameters. It was found that the static friction for wheat-wheat and wheat-acrylic contact and the rolling friction for wheat-wheat contact had a significant effect on the repose angle, while the other 5 parameters' influence was negligible. Then the steepest ascent test was used to determine the optimal value range of the significant parameters. In the steepest ascent test, the 5 non-significant parameters were the mid-value of the corresponding initial region, while the 3 significant parameters increased progressively until the relative errors between the simulated and the test value reached the minimum. Based on the result of the Box-Behnken test, a quadratic polynomial model for the repose angle and the 3 significant parameters was created. The analysis of variance (ANOVA) of the quadratic polynomial model showed that the model was significant and the lack-of-fit was non-significant. This means the model can be used to
Roering, Joshua J.; Mackey, Benjamin H.; Handwerger, Alexander L.; Booth, Adam M.; Schmidt, David A.; Bennett, Georgina L.; Cerovski-Darriau, Corina
2015-05-01
In mountainous settings, increases in rock uplift are often followed by a commensurate uptick in denudation as rivers incise and steepen hillslopes, making them increasingly prone to landsliding as slope angles approach a limiting value. For decades, the threshold slope model has been invoked to account for landslide-driven increases in sediment flux that limit topographic relief, but the manner by which slope failures organize themselves spatially and temporally in order for erosion to keep pace with rock uplift has not been well documented. Here, we review past work and present new findings from remote sensing, cosmogenic radionuclides, suspended sediment records, and airborne lidar data, to decipher patterns of landslide activity and geomorphic processes related to rapid uplift along the northward-migrating Mendocino Triple Junction in Northern California. From historical air photos and airborne lidar, we estimated the velocity and sediment flux associated with active, slow-moving landslides (or earthflows) in the mélange- and argillite-dominated Eel River watershed using the downslope displacement of surface markers such as trees and shrubs. Although active landslides that directly convey sediment into the channel network account for only 7% of the landscape surface, their sediment flux amounts to more than 50% of the suspended load recorded at downstream sediment gaging stations. These active slides tend to exhibit seasonal variations in velocity as satellite-based interferometry has demonstrated that rapid acceleration commences within 1 to 2 months of the onset of autumn rainfall events before slower deceleration ensues in the spring and summer months. Curiously, this seasonal velocity pattern does not appear to vary with landslide size, suggesting that complex hydrologic-mechanical feedbacks (rather than 1-D pore pressure diffusion) may govern slide dynamics. A new analysis of 14 yrs of discharge and sediment concentration data for the Eel River indicates
Bending of a nonlinear beam reposing on an unilateral foundation
Directory of Open Access Journals (Sweden)
Machalová J.
2011-06-01
Full Text Available This article is going to deal with bending of a nonlinear beam whose mathematical model was proposed by D. Y. Gao in (Gao, D. Y., Nonlinear elastic beam theory with application in contact problems and variational approaches,Mech. Research Communication, 23 (1 1996. The model is based on the Euler-Bernoulli hypothesis and under assumption of nonzero lateral stress component enables moderately large deflections but with small strains. This is here extended by the unilateralWinkler foundation. The attribution unilateral means that the foundation is not connected with the beam. For this problem we demonstrate a mathematical formulation resulting from its natural decomposition which leads to a saddle-point problem with a proper Lagrangian. Next we are concerned with methods of solution for our problem by means of the finite element method as the paper (Gao, D. Y., Nonlinear elastic beam theory with application in contact problems and variational approaches, Mech. Research Communication, 23 (1 1996 has no mention of it. The main alternatives are here the solution of a system of nonlinear nondifferentiable equations or finding of a saddle point through the use of the augmented Lagrangian method. This is illustrated by an example in the final part of the article.
THE INFLUENCE OF THE PUERPERAL AFFECTIONS ON INSEMINATION INDEX AND UTERINE REPOSE IN COWS
Directory of Open Access Journals (Sweden)
PĂCALĂ N.
2007-01-01
Full Text Available The observations were made, through a year, at SD Timisoara on cows fromHolstein-Friesian and Fleckvieh breed. The puerperal period was observed, theincidence of the endometrites was recorded and there were calculated tworeproduction parameters: the Insemination Index (Ig and the Uterine Reposeduration (UR (Open days. The Insemination Index (service/conception (Igrepresents the mean number of artificial inseminations performed in order to obtaina pregnancy. Uterine Repose represents the time interval, in days, from calving untilthe fecund insemination. The Uterine Repose has two components: VoluntaryWaiting Period (VWP (time interval from calving until the introduction of thefemale to reproduction and Service Period (SP (time interval from the end of theVWP until the fecund insemination. There were noticed that the incidence of theuterine infections were significant higher (p<0.05 at cows from Holstein-Friesianbreed (63.3%, compared to the cows from Fleckvieh breed (41.3%. TheInsemination Index was significant lower (p<0.05 at cows without uterine infections(1.9, compared to the cows with uterine infections (2.5. The mean duration of theUterine Repose was significant lower (p<0.05 at healthy cows (114.7 days,compared with cows with uterine infections after calving (182.2 days. It seams thatthe cows from Fleckvieh breed are more resistant to the exploitation conditions formilk production than compared with cows from Holstein-Friesian breed.
Differential thermal bleaching susceptibilities amongst coral taxa: re-posing the role of the host
Wooldridge, Scott A.
2014-03-01
It is well established that different coral species have different susceptibilities to thermal stress, yet it is less clear which biological or physical mechanisms allow some corals to resist thermal stress, whereas other corals bleach and die. Although the type of symbiont is clearly of fundamental importance, many aspects of coral bleaching cannot be explained solely by differences in symbionts amongst coral species. Here, I use the CO2 (sink) limitation model of coral bleaching to repose various host traits believed to influence thermal tolerance (e.g. metabolic rates, colony tissue thickness, skeletal growth form, mucus production rates, tissue concentration of fluorescent pigments and heterotrophic feedings capacity) in terms of an integrated strategy to reduce the likelihood of CO2 limitation around its intracellular photosymbionts. Contrasting observational data for the skeletal vital effect on oxygen isotope composition (δ18O) partitions two alternate evolutionary strategies. The first strategy is heavily reliant on a sea water supply chain of CO2 to supplement respiratory CO2(met). In contrast, the alternate strategy is less reliant on the sea water supply source, potentially facilitated by increased basal respiration rates and/or a lower photosynthetic demand for CO2. The comparative vulnerability of these alternative strategies to modern ocean conditions is used to explain the global-wide observation that corals with branching morphologies (and thin tissue layers) are generally more thermally sensitive than corals with massive morphologies (and thick tissue layers). The life history implications of this new framework are discussed in terms of contrasting fitness drivers and past environmental constraints, which delivers ominous predictions for the viability of thin-tissued branching and plating species during the present human-dominated ("Anthropocene") era of the Earth System.
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
Energy Technology Data Exchange (ETDEWEB)
Massiera, M.; Vautour, J.; Szostak-Chrzanowski, A. [Moncton Univ., NB (Canada). Dept. of Civil Engineering
2007-07-01
This study examined whether it is possible to construct a concrete face rockfill dam (CFRD) on dense moraine deposits varying from 10 to 140 metres in thickness. CFRDs are known to deform during construction and under the influence of water load as the reservoir is filled. The study was performed for dams of 75, 100, 125 and 150 metres in height with 2 different type sections, namely upstream and downstream slopes. The movement of the upstream face and internal displacements in each of the dams was simulated during construction as well as during reservoir filling. It was revealed that as the rockfill deforms under water pressure, the concrete face follows the rockfill deformation. Slope stability was analyzed at the end of the reservoir filling, and stress strain was analyzed in order to calculate the upstream face displacements and the internal movements in the rockfill embankment and the till foundation. It was concluded that it is possible to erect CFRDs on dense to very dense till deposits while maintaining safety coefficients of slopes that are satisfactory and compatible with the structural integrity of the concrete face. 19 refs., 3 tabs., 9 figs.
Institute of Scientific and Technical Information of China (English)
陈金辉; 罗志宏; 杨蕊; 康晶; 王永平; 杨希林; 朱明万; 陶泽璋
2012-01-01
Objective To investigate the complications of hyoid suspension with Repose system on obstructive sleep apnea hypopnea syndrome(OSAHS) and to find out the effective prevention strategies.Methods Forty four patients diagnosed by polysomnography as OSAHS were received hyoid suspension with Repose system from June 2005 to July 2009. The intraoperative and postoperative complications were analyzed retrospectively.The patients who reported abnormal swallowing were evaluated with water drinking test and video fluoragraphy swallow study to assess biomechanical changes in swallowing.Results Incidence rate of perioperative titanium nial amotio was 15.9％ (7/44).It was avoided by implanting titanium nial again.No perioperative complications occurred such as injury of superior laryngeal nerve,blood vessel and thyrohyoid membrane,fracture of hyoid bone,suture break. All patients developed dysfunctions of pronunciation and swallowing,edema of mouth floor,dysfunctions of movement of tongue that could relieved gradually after three days on most patients.No postoperative complications occurred such as titanium nial amotio,fat liquoring,edema of mouth floor,hematoma,infection,foreign body reaction,injury of root apex of anterior tooth,dysfunctions of movement and sensation of tongue,suture break and death.All patients had over 2 year postoperative follow up.Incidence rate of dysfunctions of pronunciation and swallowing was 4.5％ ( 2/44 ) and 15.9％ ( 7/44 ) respectively. Main situation for dysfunctions of pronunciation was speaking ambiguity.Major manifestations of swallowing abnormalities were occasional aspiration,food going down the wrong tube,food becoming stuck in the throat,deglutions with bowing head.Seven patients who had abnormal swallowing possesed normal water drinking test and occurred asynersis of hyoid movement and laryngeal elevation,but aspiration were not observed.Three patients presented obvious stagnation in epiglottic vallecula and sinus piriformis
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)
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.)
Evaluation of the Glidant Property of Fonio Starch
Muazu, J
2010-01-01
Fonio starch was evaluated as a glidant in comparison with corn starch and talc in Folic acid tabletformulation. The glidant property was analysed using the Flow rate, flow factor and angle of Repose of thegranules while the quality of the tablet was assessed by crushing strength, Friability, disintegration anddissolution times of the tablet. The result of angle of repose, flow rate and flow factor indicated that Foniostarch compares well with both corn starch and talc at concentration of 2%w...
Antesh Kumar Jha; Dipak Chetia
2011-01-01
The objective of the present study was to develop fast-dissolving tablets (FDTs) of glipizide, a sulfonylurea antidiabetic drug. The husk of Plantago ovata and pregelatinized husk of P. ovata were used as disintegrating agents. Microcrystalline cellulose was used as binder and starch (soluble) was used as bulk-forming agent. The powder blends were evaluated for angle of repose, compressibility index and Hausner ratio. The results of angle of repose, compressibility index (%) and Hausner ratio...
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...
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...
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.
Energy Technology Data Exchange (ETDEWEB)
Massiera, M.; Vautour, J.; Szostak-Chrzanowski, A. [Moncton Univ., NB (Canada). Dept. of Civil Engineering
2008-07-01
Dam safety depends on proper design, construction, and monitoring of actual behaviour during construction and during the operation of the structure. This study examined whether it is possible to construct a concrete face rockfill dam (CFRD) on dense moraine deposits of up to 140 metres in thickness. CFRDs are known to deform during construction and under the influence of water load as the reservoir is filled. The study was performed for dams of 75, 100, 125 and 150 metres in height with 2 different type sections, namely upstream and downstream slopes. The movement of the upstream face and internal displacements in each of the dams was simulated during construction as well as during reservoir filling. Two sets of deformation analyses for CFRDs were presented. First, slope stability was analyzed at the end of the reservoir filling. Next, the stress-strain was analysed in order to calculate the upstream face displacements and the internal movements that occur in the rockfill embankment and the till foundation during the construction phase as well as the reservoir filling phase. It was concluded that it is possible to erect CFRDs on dense to very dense till deposits while maintaining safety coefficients of slopes that are compatible with the structural integrity of the concrete face. The CFRDs built on compact to dense granular alluvium deposits should have a thickness of less than 60 metres and the granular alluvium foundation should be compacted to a depth of 30 metres. 17 refs., 5 tabs., 9 figs.
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.
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...
Institute of Scientific and Technical Information of China (English)
黄长伟; 詹义正; 卢金友
2008-01-01
该文基于均匀沙的楔入堆积模式,考虑粘结力及动水作用等影响,建立了相应的力学平衡方程.由此获得了粘性～散体均匀沙的动水休止角计算公式;该式较为全面地包含了影响动水休止角的主要因素;计算分析表明,公式所反映的规律与实际情况较为接近,可为沙波运动、河相关系等相关后续研究提供参考,具有实用价值.
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...
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.
The dead and gone: Preparations and final repose
US Fish and Wildlife Service, Department of the Interior — The relations between the living and the dead are sanctioned by specific departure ceremonies and a series of maintenance operations that vary in their elaboration...
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
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.)
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...
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.
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.
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.
International Nuclear Information System (INIS)
Apart from its radiation effects on living organism, radon induces the formation of atmospheric ions which are beneficial to man: some asthmatics can breathe more easily in an environment with elevated ion levels, the blood pH increases, the fraction of albumins is higher while the serotonin level is lower, sedimentation decreases and the leukocyte counts in peripherals diminish. The blood pressure, particularly in people suffering from hypertension, drops appreciably. The production of pituitary hormones as well as the overall sexual activity is stimulated by ions in air. Exposure to negative ions affects circulation through the skin, reduces skin temperature and improves overall resistance of the organism to infection. Negative ions also have a stimulating effect on mental activity and help against insomnia. Sites where radon is present in not too high concentrations are often famous as climatic spas. So, antiradon provisions, if exercised too thoroughly, may have adverse rather than positive consequences. All pros and cons should always be taken into account when deciding on antiradon steps. (P.A.)
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.
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.
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
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...
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
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)
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.
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 ...
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
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
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....
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...
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))
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)
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)
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...
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.
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 ...
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.
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.
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 ...
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...
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
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.
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.
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...
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
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
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.
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.
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
Physical properties of watermelon seed as a function of moisture content and variety
Directory of Open Access Journals (Sweden)
S. Izadkhah
2007-12-01
Full Text Available The physical properties of three common Iranian varieties of melon seeds have been evaluated as a function of seed moisture content varying from 4.75 to 47.6, from 5.02 to 46.81, and from 4.55 to 45.22% (w.b. for Ghermez, Kolaleh and Sarakhsi, respectively. Increasing moisture content was found to increase axial dimensions, surface area, emptying angle of repose, bulk and true density, sphericity, geometric and arithmetic mean diameters, and static friction coefficient on five structural surfaces, while decreasing porosity and filling angle of repose. Among the varieties, Ghermez had the highest values of geometrical properties, in all moisture contents studied. An increase of surface area with moisture content was observed. The maximum values of bulk density and true density among the varieties were obtained for Kolaleh seeds. Ghermez melon seed had the highest porosity which decreased with increase in moisture content. The filling angle of repose decreased as the moisture contents increased for all three varieties. The maximum and minimum values for emptying angle of repose were obtained for Sarakhsi and Kolaleh. At all moisture contents, plywood showed the highest friction coefficient, followed by galvanized iron sheet, then fibreglass, and finally glass. The increase in friction coefficient with moisture content was the largest for Ghermez melon seed on fibreglass surface, followed by Sarakhsi and Kolaleh on fibreglass and galvanized iron sheet surface, respectively. Ghermez variety had the highest friction on all frictional surfaces at all moisture levels.
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...
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.
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.
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.
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.
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.)
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.
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.
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
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...
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°.
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.
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...
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.
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.
Stability of submerged slopes on the flanks of the Hawaiian Islands, a simplified approach
Energy Technology Data Exchange (ETDEWEB)
Lee, H.J.; Torresan, M.E.; McArthur, W.
1994-12-31
Undersea transmission lines and shoreline AC-DC conversion stations and near-shore transmission lines are being considered as part of a system for transporting energy between the Hawaiian Islands. These facilities will need to be designed so that they will not be damaged or destroyed by coastal or undersea landslides. Advanced site surveys and engineering design of these facilities will require detailed site specific analyses, including sediment sampling and laboratory testing of samples, in situ testing of sediment and rock, detailed charting of bathymetry, and two- or three-dimensional numerical analyses of the factors of safety of the slopes against failure from the various possible loading mechanisms. An intermediate approximate approach can be followed that involves gravity and piston cores, laboratory testing and the application of simplified models to determine a seismic angle of repose for actual sediment in the vicinity of the planned facility. An even simpler and more approximate approach involves predictions of angles of repose using classification of the sediment along a proposed route as either a coarse volcaniclastic sand, a calcareous ooze, or a muddy terrigenous sediment. The steepest slope that such a sediment can maintain is the static angle of repose. Sediment may be found on slopes as steep as these, but it must be considered metastable and liable to fail in the event of any disturbance, storm or earthquake. The seismic angle of repose likely governs most slopes on the Hawaiian Ridge. This declivity corresponds to the response of the slope to a continuing seismic environment. As a long history of earthquakes affects the slopes, they gradually flatten to this level. Slopes that exceed or roughly equal this value can be considered at risk to fail during future earthquakes. Seismic and static angles of repose for three sediment types are tabulated in this report.
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.
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...
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
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)
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.
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...
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.
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 ...
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.
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 ...
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.
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...
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.
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.
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
Physical characterization of coffee after roasting and grinding
Directory of Open Access Journals (Sweden)
Gabriel Henrique Horta de Oliveira
2014-09-01
Full Text Available Flowability is an important characteristic of handling process for efficiency and reliability purpose of post-harvest operations, which are governed by the physical properties of the product. Physical properties determination is an important factor for formulation of machinery projects and sizing of post-harvest operations, which may impact considerably on the products quality, influencing directly the operation cost and company profit. Thus, the objective of this work was to evaluate and determinate some physical properties (repose angle, unit and bulk density, porosity and color coordinates, particle size, moisture content, water activity, angle of internal friction and effective angle of internal friction of coffee, such as to evaluate the influence of different roast and grinding degrees over these properties. Crude grain coffee (Coffea canephora and Coffea arabica, dehulled and dried were used. These were roasted at two levels: medium light and medium-dark brown, which Agtron numbers are, respectively, SCAA#65 and SCAA#45. After roasting process, grains were grinded at three particle sizes (thin, medium and thick. Both particle size and roast degree significantly affected physical properties of coffee. Coffee samples roasted at medium dark level obtained lower values of moisture content, water activity, repose angle, bulk and real density. Coffee samples grinded at level thin presented an increase of angle of internal friction and effective angle of internal friction, repose angle, bulk and real density, porosity and decrease of water activity values.
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.)
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 ...
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)
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)
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.
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
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.
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.
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.
Yaw Control At High Angles Of Attack
Murri, Daniel G.; Rao, Dhanvada M.
1988-01-01
Hinged, conformal forebody strakes provide control when rudders become ineffective. Device consists of symmetric pair of longitudinally hinged strakes designed to fold completely into forebody contour. Strakes rotate individually out into external flow. Asymmetric flow produced by deployed strake generates sideward force causing aircraft to yaw.
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...
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.
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.
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.
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.
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
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...
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.
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.
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.
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.
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...
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.
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
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
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
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.
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...
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.
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
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.
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
Angling for ecological effects of marine protection (SW Portugal
Directory of Open Access Journals (Sweden)
Maria João Tavares
2015-10-01
Multivariate analyses of the abundance of fish caught by size class found significant effects of protection in shore angling total weight (higher values in MPA. Lack of significant effects of protection may be due to the fact that MPAs are still recent. Replication in time, within a monitoring programme, is recommended to assess the ecological effects of these conservation measures.
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.)
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.
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.
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.
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.
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.
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)
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.
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.
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)
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...
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
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...
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.
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.
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.
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.)
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.
Custom optimisation of wedge angles in prostate radiotherapy
International Nuclear Information System (INIS)
A method for computing optimised wedge angles will be presented along with a performance evaluation over 12 patients with early prostate cancer. The method (an optimisation algorithm) was applied to standard 3 field treatment plans for each patient. The optimisation algorithm was based on simulated anealing using an efficient dose based cost function. The algorithm has been run in three PLAN MODES: (1) where the wedge angles were fixed by the human planner and only the beam-weights were optimised; (2) where both the wedge angles and beam-weights were optimised; and (3) where both the wedge angles and beam-weights were optimised and a non-uniform dose was prescribed to the PTV. In the latter PLAN MODE, a uniform 100% dose was prescribed to all of the PTV except for that region that overlaps with the rectum where a lower (e.g. 90%) dose was prescribed. The resulting optimised plans have been compared with those of the human planner who found beam-weights by conventional forward planning. Plans were compared on the basis of dose statistics, normal-tissue-complication-probability (NTCP) and tumour-control-probability (TCP). The results show that all 3 PLAN MODES produced plans with slightly higher TCP for the same rectal NTCP, than the human planner. The best results were observed for PLAN MODE 3, where a non-uniform PTV dose was prescribed. An average increase in TCP of 0.73% (± 0.20 95% confidence interval) is predicted. Probably the most significant benefit of the algorithm in the prostate setting is the time saved (about a factor of 10) in computing optimised beam-weights and wedge angles for this simple plan
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.
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
Mandibular Angle Fractures: Comparison of One Miniplate vs. Two Miniplates
Directory of Open Access Journals (Sweden)
Saeed Hajmohammadi
2013-01-01
Full Text Available Background: Monocortical miniplate fixation is an accepted and reliable method for internal fixation of mandibular angle fractures. Although placement of a second miniplate may theoretically provide more stability; however, the clinical importance of this issue remains controversial.Objectives: The present study assessed the postoperative complications and outcomes associated with the fixation of mandibular angle fractures using 1 and 2 miniplates in patients with favorable mandibular angle fractures.Patients and Methods: A prospective study of 87 patients (73 males, 14 females with favorable mandibular angle fractures was done. In the first group, a 4-hole miniplate was placed at the superior border through an intraoral approach. In group 2, patients were treated with 2 miniplates, one placed at the superior border (similar to group 1 and the other on the lateral aspect of the angle at the inferior border through an intraoral and transcutaneous approach using a trocar. Postoperative complications including malocclusion, malunion and sensory disturbances associated with surgery, additional maxillomandibular fixation (MMF by means of an arch bar and wires for a longer period (for delayed union and infection were assessed in patients of both groups up to 12 months postoperatively. The data were analyzed using the chi-square test.Results: In the single miniplate group, 25 patients showed lip numbness associated with surgery (55.6%, 22 patients required additional use of MMF (48.9% and 3 patients developed infections (6.7%. In the double miniplate group 20 patients showed lip numbness associated with surgery (47.6%, 18 patients required additional use of MMF (42.9% and 1 patient developed infection (2.4%. None of the patients in either group showed malocclusion or malunion. No significant difference was observed between the groups regarding overall complication rate.Conclusions: In this study, use of one miniplate or two miniplates for treatment of
Quantification of projection angle in fragment generator warhead
Directory of Open Access Journals (Sweden)
K.D. Dhote
2014-06-01
Full Text Available Tactical Ballistic Missile (TBM class target neutralization by the fragment spray of a Fragment Generator Warhead (FGW calls for quantification of fragment projection angle scatter to finalize the end game engagement logic. For conventional axi-symmetric warhead, dispersion is assumed to be normal with a standard deviation of 30. However, such information is not available in case of FGW. Hence, a set of experiments are conducted to determine the dispersion of fragments. The experiments are conducted with a specific configuration of FGW in an identical arena to quantify the scatter and then verified its applicability to other configurations having a range of L/D and C/M ratios, and contoured fragmenting discs. From the experimental study, it is concluded that the scatter in projection angle follows normal distribution with a standard deviation of 0.75° at Chi-square significance level of 0.01(χ20.99.
Incoherent photoproduction of pseudoscalar mesons off nuclei at forward angles
Gevorkyan, S; Gan, L; Larin, I; Khandaker, M
2009-01-01
Recent advances in the photon tagging facilities together with the novel, high resolution fast calorimetry made possible to perform photoproduction cross section measurements of pseudoscalar mesons on nuclei with a percent level accuracy. The extraction of the radiative decay widths, needed for testing the symmetry breaking effects in QCD, from these measurements at small angles is done by the Primakoff method. This method requires theoretical treatment of all processes participating in these reactions at the same percent level. The most updated description of general processes, including the nuclear coherent amplitude, is done in our previous paper. In this work, based on the framework of Glauber multiple scattering theory, we obtain analytical expressions for the incoherent cross section of the photoproduction of pseudoscalar mesons off nuclei accounting for the mesons absorption in nuclei and Pauli suppression at forward production angles. As illustrations of the obtained formulas, we calculate the incoher...
Refractivity estimations from an angle-of-arrival spectrum
Institute of Scientific and Technical Information of China (English)
Zhao Xiao-Feng; Huang Si-Xun
2011-01-01
This paper addresses the probability of atmospheric refractivity estimation by using field measurements at an array of radio receivers in terms of angle-of-arrival spectrum. Angle-of-arrival spectrum information is simulated by the ray optics model and refractivity is expressed in the presence of an ideal tri-linear profile. The estimation of the refractivity is organized as an optimization problem and a genetic algorithm is used to search for the optimal solution from various trial refractivity profiles. Theoretical analysis demonstrates the feasibility of this method to retrieve the refractivity parameters. Simulation results indicate that this approach has a fair anti-noise ability and its accuracy performance is mainly dependent on the antenna aperture size and its positions.
The Spectral Sharpness Angle of Gamma-ray Bursts
Yu, Hoi-Fung; Greiner, Jochen; Sari, Re'em; Bhat, P Narayana; von Kienlin, Andreas; Paciesas, William S; Preece, Robert D
2016-01-01
We explain the results of Yu et al. (2015b) of the novel sharpness angle measurement to a large number of spectra obtained from the Fermi gamma-ray burst monitor. The sharpness angle is compared to the values obtained from various representative emission models: blackbody, single-electron synchrotron, synchrotron emission from a Maxwellian or power-law electron distribution. It is found that more than 91% of the high temporally and spectrally resolved spectra are inconsistent with any kind of optically thin synchrotron emission model alone. It is also found that the limiting case, a single temperature Maxwellian synchrotron function, can only contribute up to 58+23 -18% of the peak flux. These results show that even the sharpest but non-realistic case, the single-electron synchrotron function, cannot explain a large fraction of the observed spectra. Since any combination of physically possible synchrotron spectra added together will always further broaden the spectrum, emission mechanisms other than optically...
Dynamic contact angle of water-based titanium oxide nanofluid
Radiom, Milad; Yang, Chun; Chan, Weng Kong
2013-01-01
Abstract This paper presents an investigation into spreading dynamics and dynamic contact angle of TiO2-deionized water nanofluids. Two mechanisms of energy dissipation, (1) contact line friction and (2) wedge film viscosity, govern the dynamics of contact line motion. The primary stage of spreading has the contact line friction as the dominant dissipative mechanism. At the secondary stage of spreading, the wedge film viscosity is the dominant dissipative mechanism. A theoretical model based ...
Oscillations of Relative Inclination Angles in Compact Extrasolar Planetary Systems
Becker, Juliette C.; Adams, Fred 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 appe...
Pitch Angle Control of Variable Speed Wind Turbine
Yousif El-Tous
2008-01-01
The aim of this study is to design a simple controller to maximize the extracted energy of wind turbines. In this study the pitch angle control of variable speed wind turbine is investigated. In particular, it concentrates on the extraction of maximum available energy, reduction of torque and output power variations, which gives stresses in the gearbox and mechanical structure. The control concentrates on separate wind speed internals as well as on whole wind speed region. It is found that th...
Brownian Motion on a Sphere: Distribution of Solid Angles
Krishna, M. M. G.; Samuel, Joseph; Sinha, Supurna
2000-01-01
We study the diffusion of Brownian particles on the surface of a sphere and compute the distribution of solid angles enclosed by the diffusing particles. This function describes the distribution of geometric phases in two state quantum systems (or polarised light) undergoing random evolution. Our results are also relevant to recent experiments which observe the Brownian motion of molecules on curved surfaces like micelles and biological membranes. Our theoretical analysis agrees well with the...
Simultaneous Multi-angle Measurements of Plasma Turbulence at HAARP
Watanabe, Naomi; Golkowski, Mark; Sheerin, James; University of Colorado Denver Team
2013-10-01
We report the results from a recent series of experiments employing the HAARP HF transmitter to generate and study strong Langmuir turbulence (SLT) in the interaction region of overdense ionospheric plasma. Diagnostics included the Modular UHF Ionospheric Radar (MUIR) located at HAARP, the Super DARN-Kodiak HF radar, and HF receivers to record stimulated electromagnetic emissions (SEE). Short pulse, low duty cycle experiments demonstrate control and suppression of artificial field-aligned irregularities (AFAI). This allows the isolation of ponderomotive plasma turbulence effects. For the first time, plasma line spectra measured simultaneously in different spots of the interaction region displayed marked but contemporaneous differences dependent on the aspect angle of the HF pump beam and the pointing angle of the MUIR diagnostic radar. Outshifted Plasma Line (OPL) spectra, rarely observed in past experiments, occurred with sufficient regularity for experimentation. Experimental results are compared to previous high latitude experiments and predictions from recent modeling efforts.
On the impact angle of Hurricane Sandy's New Jersey landfall
Hall, Timothy M.; Sobel, Adam H.
2013-05-01
Hurricane Sandy's track crossed the New Jersey coastline at an angle closer to perpendicular than any previous hurricane in the historic record, one of the factors contributing to record-setting peak-water levels in parts of New Jersey and New York. To estimate the occurrence rate of Sandy-like tracks, we use a stochastic model built on historical hurricane data from the entire North Atlantic to generate a large sample of synthetic hurricanes. From this synthetic set we calculate that under long-term average climate conditions, a hurricane of Sandy's intensity or greater (category 1+) makes NJ landfall at an angle at least as close to perpendicular as Sandy's at an average annual rate of 0.0014 yr-1 (95% confidence range 0.0007 to 0.0023); i.e., a return period of 714 years (95% confidence range 435 to 1429).
Magic-angle-spinning NMR studies of zeolite SAPO-5
Freude, D.; Ernst, H.; Hunger, M.; Pfeifer, H.; Jahn, E.
1988-01-01
SAPO-5 was synthesized using triethylamine as template. Magic-angle-spinning (MAS) NMR of 1H, 27Al, 29Si and 31P was used to study the silicon incorporation into the framework and the nature of the Brønsted sites. 1H MAS NMR shows two types of bridging hydroxyl groups. 29Si MAS NMR indicates that silicon substitutes mostly for phosphorus and that there is a small amount of crystalline SiO 2 in the zeolite powder.
The angle property of positive real functions simply derived
DEFF Research Database (Denmark)
Jørsboe, Helge
1973-01-01
The angle property of positive real (rational) functionsZ(s), namely, that|arg s | geqq |arg Z(s)|in the right half of thes-plane, can be demonstrated very simply by an examination of the imaginary parts of the functionsln(s/Z(s))andln (sZ(s)), i.e.,arg s mp arg Z(s). In particular, on a contour...
Modern Technologies of Open-Angle Glaucoma Surgery
2014-01-01
Currently, glaucoma surgery has become a major technique. Surgery is a method of choice in open-angle glaucoma, especially in those cases when conservative and laser treatments have no effect, as well as if glaucoma is inaccessible or a patient has low treatment compliance. In this review the authors give the information about the development of main glaucoma surgery directions, such as removal of pupillary block, the anterior chamber fistulization, the reduction of intraocular fluid producti...
Photoproduction of Pseudoscalar Mesons off Nuclei at Forward Angles
Gevorkyan, S; Gasparian, A.; Gan, L.; Larin, I.; Khandaker, M.
2009-01-01
With the advent of new photon tagging facilities and novel experimental technologies it has become possible to perform photoproduction cross section measurements of pseudoscalar mesons on nuclei with a percent level accuracy. The extraction of the radiative decay widths from these measurements at forward angles is done by the Primakoff method, which requires theoretical treatment of all processes participating in these reactions at the same percent level. In this work we review the theoretica...
The mixing angle as a function of neutrino mass ratio
Roy, Subhankar
2016-01-01
In the quark sector, we experience a correlation between the mixing angles and the mass ratios. A partial realization of the similar tie-up in the neutrino sector helps to constrain the parametrization of masses and mixing, and hints for a predictive framework. We derive five hierarchy dependent textures of neutrino mass matrix with minimum number of parameters ($\\leq\\,4$), following a model-independent strategy.
Scattering angle base filtering of the inversion gradients
Alkhalifah, Tariq Ali
2014-01-01
Full waveform inversion (FWI) requires a hierarchical approach based on the availability of low frequencies to maneuver the complex nonlinearity associated with the problem of velocity inversion. I develop a model gradient filter to help us access the parts of the gradient more suitable to combat this potential nonlinearity. The filter is based on representing the gradient in the time-lag normalized domain, in which low scattering angles of the gradient update are initially muted. The result are long-wavelength updates controlled by the ray component of the wavefield. In this case, even 10 Hz data can produce near zero wavelength updates suitable for a background correction of the model. Allowing smaller scattering angle to contribute provides higher resolution information to the model.
Incoherent photoproduction of pseudoscalar mesons off nuclei at forward angles
Gevorkyan, S; Gasparian, A.; Gan, L.; Larin, I.; Khandaker, M.
2009-01-01
Recent advances in the photon tagging facilities together with the novel, high resolution fast calorimetry made possible to perform photoproduction cross section measurements of pseudoscalar mesons on nuclei with a percent level accuracy. The extraction of the radiative decay widths, needed for testing the symmetry breaking effects in QCD, from these measurements at small angles is done by the Primakoff method. This method requires theoretical treatment of all processes participating in these...
Small-angle X-ray scattering of solutions
International Nuclear Information System (INIS)
The use of synchrotron radiation in small-angle X-ray scattering (SAXS) techniques in biological structural studies is described. The main features of the monochromatic radiation systems and the white radiation systems are considered. The detectors, data acquisition and experimental procedures are briefly described. Experimental results are presented for 1) measurements on dilute solutions and weak scatterers, 2) measurement of conformational transitions, 3) contrast variation experiments, 4) time-resolved measurements and 5) complex contrast variation. (U.K.)
Contact angle and film pressure: study of a talc surface.
Douillard, J M; Zajac, J; Malandrini, H; Clauss, F
2002-11-15
Talc samples in both sheet and powder form are studied by adsorption calorimetry and adsorption isotherm techniques. A model is used to determine the solid surface energy, the solid surface tension and the dispersive, acidic, and basic components of these terms. These results are introduced in an approximate equation relating adsorption to contact angle data. Experimental contact angles are in correct agreement with this approach. The Neumann equation of state is used to fit the data and discussed. It appears as a numerical form of the general equation taking into account gas adsorption and film pressure. Behaviors of talc in contact with liquids do not appear very different whether the solid is in sheet or powder form. PMID:12505082
Precision Measurement of the Weak Mixing Angle in Moller Scattering
Anthony, P L; Arroyo, C; Bega, K; Biesiada, J; Bosted, P E; Bower, G; Cahoon, J; Carr, R; Cates, G D; Chen, J P; Chudakov, E; Cooke, M; Decowski, P; Deur, A; Emam, W; Erickson, R; Fieguth, T; Field, C; Gao, J; Gary, M; Gustafsson, K; Hicks, R S; Holmes, R; Hughes, E W; Humensky, T B; Jones, G M; Kaufman, L J; Keller, L; Kolomensky, Yu G; Kumar, K S; La Violette, P; Lhuillier, D; Lombard-Nelsen, R M; Marshall, Z; Mastromarino, P; McKeown, R D; Michaels, R; Niedziela, J; Olson, M; Paschke, K D; Peterson, G A; Pitthan, R; Relyea, D; Rock, S E; Saxton, O; Singh, J; Souder, P A; Szalata, Z M; Turner, J; Tweedie, B; Vacheret, A; Walz, D; Weber, T; Weisend, J; Woods, M; Younus, I
2005-01-01
We report on a precision measurement of the parity-violating asymmetry in fixed target electron-electron (Moller) scattering: A_PV = -131 +/- 14 (stat.) +/- 10 (syst.) parts per billion, leading to the determination of the weak mixing angle \\sin^2\\theta_W^eff = 0.2397 +/- 0.0010 (stat.) +/- 0.0008 (syst.), evaluated at Q^2 = 0.026 GeV^2. Combining this result with the measurements of \\sin^2\\theta_W^eff at the Z^0 pole, the running of the weak mixing angle is observed with over 6 sigma significance. The measurement sets constraints on new physics effects at the TeV scale.
Dynamic-angle spinning and double rotation of quadrupolar nuclei
International Nuclear Information System (INIS)
Nuclear magnetic resonance (NMR) spectroscopy of quadrupolar nuclei is complicated by the coupling of the electric quadrupole moment of the nucleus to local variations in the electric field. The quadrupolar interaction is a useful source of information about local molecular structure in solids, but it tends to broaden resonance lines causing crowding and overlap in NMR spectra. Magic- angle spinning, which is routinely used to produce high resolution spectra of spin-1/2 nuclei like carbon-13 and silicon-29, is incapable of fully narrowing resonances from quadrupolar nuclei when anisotropic second-order quadrupolar interactions are present. Two new sample-spinning techniques are introduced here that completely average the second-order quadrupolar coupling. Narrow resonance lines are obtained and individual resonances from distinct nuclear sites are identified. In dynamic-angle spinning (DAS) a rotor containing a powdered sample is reoriented between discrete angles with respect to high magnetic field. Evolution under anisotropic interactions at the different angles cancels, leaving only the isotropic evolution of the spin system. In the second technique, double rotation (DOR), a small rotor spins within a larger rotor so that the sample traces out a complicated trajectory in space. The relative orientation of the rotors and the orientation of the larger rotor within the magnetic field are selected to average both first- and second-order anisotropic broadening. The theory of quadrupolar interactions, coherent averaging theory, and motional narrowing by sample reorientation are reviewed with emphasis on the chemical shift anisotropy and second-order quadrupolar interactions experienced by half-odd integer spin quadrupolar nuclei. The DAS and DOR techniques are introduced and illustrated with application to common quadrupolar systems such as sodium-23 and oxygen-17 nuclei in solids
Dynamic-angle spinning and double rotation of quadrupolar nuclei
Energy Technology Data Exchange (ETDEWEB)
Mueller, K.T. (Lawrence Berkeley Lab., CA (United States) California Univ., Berkeley, CA (United States). Dept. of Chemistry)
1991-07-01
Nuclear magnetic resonance (NMR) spectroscopy of quadrupolar nuclei is complicated by the coupling of the electric quadrupole moment of the nucleus to local variations in the electric field. The quadrupolar interaction is a useful source of information about local molecular structure in solids, but it tends to broaden resonance lines causing crowding and overlap in NMR spectra. Magic- angle spinning, which is routinely used to produce high resolution spectra of spin-{1/2} nuclei like carbon-13 and silicon-29, is incapable of fully narrowing resonances from quadrupolar nuclei when anisotropic second-order quadrupolar interactions are present. Two new sample-spinning techniques are introduced here that completely average the second-order quadrupolar coupling. Narrow resonance lines are obtained and individual resonances from distinct nuclear sites are identified. In dynamic-angle spinning (DAS) a rotor containing a powdered sample is reoriented between discrete angles with respect to high magnetic field. Evolution under anisotropic interactions at the different angles cancels, leaving only the isotropic evolution of the spin system. In the second technique, double rotation (DOR), a small rotor spins within a larger rotor so that the sample traces out a complicated trajectory in space. The relative orientation of the rotors and the orientation of the larger rotor within the magnetic field are selected to average both first- and second-order anisotropic broadening. The theory of quadrupolar interactions, coherent averaging theory, and motional narrowing by sample reorientation are reviewed with emphasis on the chemical shift anisotropy and second-order quadrupolar interactions experienced by half-odd integer spin quadrupolar nuclei. The DAS and DOR techniques are introduced and illustrated with application to common quadrupolar systems such as sodium-23 and oxygen-17 nuclei in solids.
Bank Angle of a V-Type 12-Cylinder Engine
Ito, Norio; Nakagawa, Akihito; Kitamura, Ryuji
As the automobile engine advances towards higher performance and higher power, the increase in displacement and the number of cylinders in the engine has led to larger engines. As a result, the need for rigidity countermeasures and reductions in size and weight have brought about the switch from in-line type engines to V-type engines. Currently, most of the V-type automobile engines produced have six or eight cylinders, and some large passenger cars produced in Europe and America have V-type engines with 10 or 12 cylinders. The bank angles of engines in these passenger are almost fixed based on the cylinder number. Therefore, the form of the V-type engine is limited according to the number of cylinders. The present study examines the bank angle of a V-12 engine by performing a detailed analysis of the relationship between the cylinder arrangement and the exciting moment. The goal of the present study is to find a bank angle that has as of yet not been applied to the V-type engine so that the layouts of the absorption and exhaust systems, as well as the attached apparatuses, can be reconfigured.
Precise determination of lattice phase shifts and mixing angles
Lu, Bing-Nan; Lähde, Timo A.; Lee, Dean; Meißner, Ulf-G.
2016-09-01
We introduce a general and accurate method for determining lattice phase shifts and mixing angles, which is applicable to arbitrary, non-cubic lattices. Our method combines angular momentum projection, spherical wall boundaries and an adjustable auxiliary potential. This allows us to construct radial lattice wave functions and to determine phase shifts at arbitrary energies. For coupled partial waves, we use a complex-valued auxiliary potential that breaks time-reversal invariance. We benchmark our method using a system of two spin-1/2 particles interacting through a finite-range potential with a strong tensor component. We are able to extract phase shifts and mixing angles for all angular momenta and energies, with precision greater than that of extant methods. We discuss a wide range of applications from nuclear lattice simulations to optical lattice experiments.
Variability and Similarity of Gait as Evaluated by Joint Angles
DEFF Research Database (Denmark)
Yang, Sylvia X M; Larsen, Peter Kastmand; Alkjær, Tine;
2014-01-01
Closed-circuit television (CCTV) footage is used in criminal investigations to compare perpetrators with suspects. Usually, incomplete gait cycles are collected, making evidential gait analysis challenging. This study aimed to analyze the discriminatory power of joint angles throughout a gait cycle....... Six sets from 12 men were collected. For each man, a variability range VR (mean ± 1SD) of a specific joint angle at a specific time point (a gait cycle was 100 time points) was calculated. In turn, each individual was compared with the 11 others, and whenever 1 of these 11 had a value within this...... individual’s VR, it counted as positive. By adding the positives throughout the gait cycle, we created simple bar graphs; tall bars indicated a small discriminatory power, short bars indicated a larger one. The highest discriminatory power was at time points 60–80 in the gait cycle. We show how our data can...
Measurement of Angle of Ultrasound Propagation from Phase
Energy Technology Data Exchange (ETDEWEB)
Civale, John; Rivens, Ian; Haar, Gail ter, E-mail: john.civale@icr.ac.uk [Joint Department of Physics, The Royal Marsden Hospital, Institute of Cancer Research, Downs Road, Sutton, Surrey, SM2 5PT (United Kingdom)
2011-02-01
Acoustic field calibrations often use Fast Fourier Transforms (FFT) to quantify the spectral amplitude components of detected acoustic waveforms. The ability of FFTs to provide phase information is often overlooked. This phase data may be useful in determining the angle of propagation of the ultrasound beam. The angle of propagation at the focal peak (and any other point in the field) can be calculated easily and quickly without additional measurement, and may be the quickest and most accurate method of aligning the sound axis with respect to the beamplotting system's co-ordinates. Acoustic fields have been measured experimentally using a system capable of waveform acquisition. Measurements were made using a fibre-optic hydrophone (Precision Acoustics, UK) which provided spatial resolution of <100 {mu}m. Two operating configurations of a 10 strip array HIFU (high intensity focused ultrasound) transducer were tested, as was a single element HIFU device. Theoretical pressure and phase distributions for these transducers were predicted using a linear acoustic field model. Results show that for the single element, radially symmetric device, beam alignment measurements using phase data at the focal peak are in agreement with the more conventional method based on finding the on-axis peak positions. In the case of a transducer with a number of elements de-activated to produce an asymmetric ultrasound source, the angle of propagation at the focal peak was altered, indicating a change in performance of the transducer which otherwise might not have been detected using the 'on-axis peaks' method. Simulations agreed with the experimental data.
Approach for measuring the angle of hallux valgus
Jin Zhou; Petr Hlavacek; Bo Xu; Wuyong Chen
2013-01-01
Background: There is medium correlation between the current anthropometric method and the radiography in the angle of hallux valgus (AoH) measurement, so this study aimed at designing a reliable and more accurate approach to measure the AoH (AoH). Materials and Methods: Fifteen age, body weight, and height matched male students were included and those with foot disorders, deformities, or injuries were excluded from the study. The dorsal protrusions of the first metatarsal and the hallux we...
Investigation of Brazed Plate Heat Exchangers With Variable Chevron Angles
S. Muthuraman
2013-01-01
- 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 pressur...
High angle of attack aerodynamics subsonic, transonic, and supersonic flows
Rom, Josef
1992-01-01
The aerodynamics of aircraft at high angles of attack is a subject which is being pursued diligently, because the modern agile fighter aircraft and many of the current generation of missiles must perform well at very high incidence, near and beyond stall. However, a comprehensive presentation of the methods and results applicable to the studies of the complex aerodynamics at high angle of attack has not been covered in monographs or textbooks. This book is not the usual textbook in that it goes beyond just presenting the basic theoretical and experimental know-how, since it contains reference material to practical calculation methods and technical and experimental results which can be useful to the practicing aerospace engineers and scientists. It can certainly be used as a text and reference book for graduate courses on subjects related to high angles of attack aerodynamics and for topics related to three-dimensional separation in viscous flow courses. In addition, the book is addressed to the aerodynamicist...
Determination of the angle of attack on rotor blades
DEFF Research Database (Denmark)
Shen, Wen Zhong; Hansen, Martin Otto Laver; Sørensen, Jens Nørkær
2009-01-01
Two simple methods for determining the angle of attack (AOA) on a section of a rotor blade are proposed. Both techniques consist of employing the Biot-Savart integral to determine the influence of the bound vorticity on the velocity field. In the first technique, the force distribution along the...... techniques. The advantage of the proposed techniques, as compared with existing techniques, is that they can be used to determine the AOA on rotor blades under general flow conditions (e.g. operations in yaw or with dynamic inflow)....
Precise determination of lattice phase shifts and mixing angles
Lu, Bing-Nan; Lee, Dean; Meißner, Ulf-G
2015-01-01
We introduce a general method for determining phase shifts and mixing angles on the lattice with greater precision than existing methods. The approach starts with angular momentum projection on the lattice wave functions in order to construct lattice radial wave functions. We then impose spherical wall boundaries together with an adjustable auxiliary potential to determine phase shifts at arbitrary energy. For coupled partial waves, we use a complex-valued auxiliary potential that breaks time-reversal invariance in order to extract phase shifts and mixing angles from the complex-valued wave functions. We benchmark the method using a system of two spin-1/2 particles interacting through a finite-range potential with a strong tensor component, and find that scattering parameters can be extracted precisely for all angular momenta and energies. We discuss the application of the method to ab initio lattice Monte Carlo studies.
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 ...
The power of pictures: Vertical picture angles in power pictures
Giessner, Steffen; Ryan, Michelle; Schubert, Thomas; van Quaquebeke, Niels
2011-01-01
textabstractAbstract: 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 diverse perspectives of evolutionary, social learning, and embodiment theories all suggest that the association between verticality and power is relatively automatic and should...
LHCb Measurement of the CKM angle $\\gamma$ at LHCb
Ali, S
2014-01-01
In this poster we present the latest result by the LHCb collaboration in determining the CKM angle $\\gamma$ ($(67.1 \\pm 12)^{\\circ}$). The result is determined by combining several $B \\to Dh$ analyses. Latest results from the decay time dependent $B_{s} \\to D_{s}K$ analysis is also reported, along with a few other decay channels interesting for determination of $\\gamma$ in the future.
Faraday cage angled-etching of nanostructures in bulk dielectrics
Latawiec, Pawel; Burek, Michael J.; Sohn, Young-Ik; Lončar, Marko
2016-01-01
For many emerging optoelectronic materials, heteroepitaxial growth techniques do not offer the same high material quality afforded by bulk, single-crystal growth. However, the need for optical, electrical, or mechanical isolation at the nanoscale level often necessitates the use of a dissimilar substrate, upon which the active device layer stands. Faraday cage angled-etching (FCAE) obviates the need for these planar, thin-film technologies by enabling in-situ device release and isolation thro...
Compensation of the Crossing Angle with Crab Cavities at KEKB
Abe, T; Akemoto, M; Akiyama, A; Arinaga, M; Ebihara, K; Egawa, K; Enomoto, A; Flanagan, J; Fukuda, S; Fukuma, H; Funakoshi, Y; Furukawa, K; Furuya, T; Hara, K; Higo, T; Hiramatsu, S; Hisamatsu, H; Honma, H; Honma, T; Hosoyama, K; Ieiri, T; Iida, N; Ikeda, H; Ikeda, M; Inagaki, S; Isagawa, S; Ishii, H; Kabe, A; Kadokura, E; Kageyama, T; Kakihara, K; Kako, E; Kamada, S; Kamitani, T; Kanazawa, K; Katagiri, H; Kato, S; Kawamoto, T; Kazakov, S; Kikuchi, M; Kikutani, E; Kitagawa, K; Koiso, H; Kojima, Y; Komada, I; Kubo, T; Kudo, K; Kudo, N; Marutsuka, K; Masuzawa, M; Matsumoto, S; Matsumoto, T; Michizono, S; Mikawa, K; Mimashi, T; Mitsunobu, S; Mori, K; Morita, A; Morita, Y; Nakai, H; Nakajima, H; Nakamura, T T; Nakanishi, H; Nakanishi, K; Nakao, K; Ninomiya, S; Ogawa, Y; Ohmi, K; Ohsawa, S; Ohsawa, Y; Ohnishi, Y; Ohuchi, N; Oide, K; Ono, M; Ozaki, T; Saitô, K; Sakai, H; Sakamoto, Y; Sato, M; Satoh, M; Shibata, K; Shidara, T; Shirai, M; Shirakawa, A; Sueno, T; Suetake, M; Suetsugu, Y; Sugahara, R; Sugimura, T; Suwada, T; Tajima, O; Takano, S; Takasaki, S; Takenaka, T; Takeuchi, Y; Tawada, M; Tejima, M; Tobiyama, M; Tokuda, N; Uehara, S; Uno, S; Yamamoto, Y; Yano, Y; Yokoyama, K; Yoshida, Ma; Yoshida, Mi; Yoshimoto, S; Yoshino, K; Perevedentsev, E; Shatilov, D N
2007-01-01
Crab cavities have been installed in the KEKB B--Factory rings to compensate the crossing angle at the collision point and thus increase luminosity. The beam operation with crab crossing has been done since February 2007. This is the first experience with such cavities in colliders or storage rings. The crab cavities have been working without serious issues. While higher specific luminosity than the geometrical gain has been achieved, further study is necessary and under way to reach the prediction of simulation.
To a question of determining the mining boundary angle in subsidence
Sedlák Vladimír; Novák Josef
2004-01-01
The mining boundary angle, as one of the basic parameters of subsidence, is used a lot of methods at prediction calculation of movements and deformations. The mining boundary angle is used at determining so called the pillar angles at the protected pillar of warehouses on the earth surface. This mining boundary angle together with the mining depth characterises the subsidence measure on the earth surface. The mining boundary angle depends upon geological, hydrogeological relations and deforma...
Research and application of multi-angle polarization characteristics of water body mirror reflection
Institute of Scientific and Technical Information of China (English)
2007-01-01
On the basis of the multi-angle polarized reflection spectrum of the water samples,the water body mirror reflection polarization characteristics and mechanism are described systematically. By altering such influential factors as the angle of incidence,detecting angle,detecting azimuth angle and polari-zation angle,ubiquitous laws for the multi-angle polarized reflection spectrum of the water samples are obtained. Combining multi-angle remote sensing with polarized light,the multi-angle polarized reflec-tion method about eliminating the water body mirror reflection and the suitable time of the polarized remote sensing of the water body are proposed. This study provides technical references for the ap-plication of multi-angle polarization technology on water body remote sensing.
Research and application of multi-angle polarization characteristics of water body mirror reflection
Institute of Scientific and Technical Information of China (English)
LUO YangJie; ZHAO YunSheng; LI XiaoWen; WU TaiXia; ZHAO LiLi
2007-01-01
On the basis of the multi-angle polarized reflection spectrum of the water samples, the water body mirror reflection polarization characteristics and mechanism are described systematically. By altering such influential factors as the angle of incidence, detecting angle, detecting azimuth angle and polarization angle, ubiquitous laws for the multi-angle polarized reflection spectrum of the water samples are obtained. Combining multi-angle remote sensing with polarized light, the multi-angle polarized reflection method about eliminating the water body mirror reflection and the suitable time of the polarized remote sensing of the water body are proposed. This study provides technical references for the application of multi-angle polarization technology on water body remote sensing.
Starlight emergence angle error analysis of star simulator
Zhang, Jian; Zhang, Guo-yu
2015-10-01
With continuous development of the key technologies of star sensor, the precision of star simulator have been to be further improved, for it directly affects the accuracy of star sensor laboratory calibration. For improving the accuracy level of the star simulator, a theoretical accuracy analysis model need to be proposed. According the ideal imaging model of star simulator, the theoretical accuracy analysis model can be established. Based on theoretically analyzing the theoretical accuracy analysis model we can get that the starlight emergent angle deviation is primarily affected by star position deviation, main point position deviation, focal length deviation, distortion deviation and object plane tilt deviation. Based on the above affecting factors, a comprehensive deviation model can be established. According to the model, the formula of each factors deviation model separately and the comprehensive deviation model can be summarized and concluded out. By analyzing the properties of each factors deviation model and the comprehensive deviation model formula, concluding the characteristics of each factors respectively and the weight relationship among them. According the result of analysis of the comprehensive deviation model, a reasonable designing indexes can be given by considering the star simulator optical system requirements and the precision of machining and adjustment. So, starlight emergence angle error analysis of star simulator is very significant to guide the direction of determining and demonstrating the index of star simulator, analyzing and compensating the error of star simulator for improving the accuracy of star simulator and establishing a theoretical basis for further improving the starlight angle precision of the star simulator can effectively solve the problem.
Potential flow past axisymmetric bodies at angle of attack
Kuhlman, J. M.; Shu, J.-Y.
1984-01-01
The Karamcheti (1966) suggestion concerning the use of higher order singularity techniques has been developed for the calculation of incompressible flow past an axisymmetric body at angle of attack. Attention is given to the results of a convergence study using this axial singularity method, where solution accuracy has been investigated for ellipsoids of slenderness ratio in the 1-10 range for both axial and inclined flow. Effects of singularity type, element number and size distribution, and singularity line inset distance, are noted, and a paneling scheme is developed which yields accurate results for the class of axisymmetric bodies having continuous body slopes with discontinuous curvature jumps.
Computation of magnetic coordinates and action-angle variables
International Nuclear Information System (INIS)
We have developed a new algorithm for calculating magnetic surfaces and coordinates for a given three-dimensional magnetic field. The algorithm serves also to solve the equivalent problem of computing invariant tori and action-angle variables for a one-dimensional time-dependent numerically specified Hamiltonian (or a two-dimensional time-independent Hamiltonian). Our approach combines features of both iterative and trajectory following methods. This allows us to overcome the inefficiency of trajectory following methods near low order rational surfaces, while retaining some of the robustness of these methods. 26 refs., 8 figs., 1 tab
Characterization of some wide viewing angle liquid crystal devices
Liu, Weimin
2001-08-01
It is well known that a standard twisted nematic (TN) display, which is most commonly used in flat panel displays, has inherently narrow and non-uniform viewing angle characteristics. Normally black TN (NBTN) displays suffer from problems with chromaticity and contrast for normal and poor grayscale at wide viewing angles. Ideal compensation of the dark state for a NBTN requires a negative birefringence film with a uniformly twisted optical axis distribution. However, such films have not been fabricated to date. In our work we approximate the twisted structure of compensation film for NBTN displays by stacking several layers of polymer film having in- plane negative retardation. Using only 4 layers of film we obtain much wider viewing cone and higher contrast compare to uncompensated NBTN. The chromaticity is also greatly improved over the uncompensated cell. Modeling of liquid crystal displays is an efficient and economical way to LCD characterization and optimization without assembling a large number of test cells. It has become a useful tool for the development of new display modes. In the past, optical simulation of LCDs has mainly relied on one-dimensional models. As the liquid crystal technology advances, multidimensional modeling is required for better understanding of optical behavior at smaller feature sizes. In our work, a generalized geometrical optics approach (GOA) has been applied to liquid crystal devices with multiple dimensions. It is faster than other approaches (e.g. FDTD) and proved to be a useful design tool for optimization of liquid crystal devices in more than one-dimension. We performed detailed characterization of the electrically-induced optical compensation (EOC) mode for information display applications. This mode shows very wide viewing angle and excellent grayscale performance when a negative birefringent compensation film is added. Using GOA, we investigated the detailed transmission profile and the viewing angle properties of EOC
Optical trapping of nanoparticles by full solid-angle focusing
Salakhutdinov, Vsevolod; Carbone, Luigi; Giacobino, Elisabeth; Bramati, Alberto; Leuchs, Gerd
2015-01-01
We propose and implement a dipole-trap for nanoparticles that is based on focusing from the full solid angle with a deep parabolic mirror. The key aspect is the generation of a linear-dipole mode. For such a mode, our calculations predict a trapping potential that is deeper and tighter than the potential obtainable with microscope objectives. We demonstrate the trapping of dot-in-rod nanoparticles. From the detected fluorescence photons we obtain intensity correlation functions of second order with $g^{(2)}(0)< 0.5$, suggesting the trapping of a single quantum emitter.
Malignant melanoma of the cerebello-pontine angle region
Directory of Open Access Journals (Sweden)
F. Menezes Braga
1989-12-01
Full Text Available A case of malignant melanoma in the cerebello-pontine angle region is presented in a 72 years old female patient, who had neurological examination and CT scan suggestive of acoustic neuroma. The surgical finding and the histological examination provided the diagnosis. As a primary focus was not found on clinical examination and although autopsy was not carried out, there is a possibility of the diagnosis being a primary malignant melanoma in CNS. This specific location for this kind of tumor was found to be rare when literature is looked up.
[Location of disease: acupoint view from the angle of clinic].
Zhang, Jian-Bin; Zou, Yang-Yang; Hu, Guang-Yong; Wu, Jiu-Long; Bai, Jie-Jing; Zhang, Shu-Jian
2014-12-01
Doctor WANG Zhi-zhong in the Southern Song Dynasty proposed the acupoint view of "location of disease", which explained the connotation of acupoints from the angle of clinic. Its meaning included two levels, one level meant pathological change on the body surface, that was the location of acupuncture diagnosis-treatment, and the other one indicated that the body surface which was the reflecting point of pathological change on the distal area or inside the body was the location of acupuncture diagnosis-treatment. The specific connotations of clinical acupoints were: location of pathogenic factors or reflection of pathogenic factors, regularity between acupoints un- der disease and specific organ, morphological differences and positioning variability after acupoints under disease, and acupoints examination, diagnosis and treatment. PMID:25876353
Review of Research On Angle-of-Attack Indicator Effectiveness
Le Vie, Lisa R.
2014-01-01
The National Aeronautics and Space Administration (NASA) conducted a literature review to determine the potential benefits of a display of angle-of-attack (AoA) on the flight deck of commercial transport that may aid a pilot in energy state awareness, upset recovery, and/or diagnosis of air data system failure. This literature review encompassed an exhaustive list of references available and includes studies on the benefits of displaying AoA information during all phases of flight. It also contains information and descriptions about various AoA indicators such as dial, vertical and horizontal types as well as AoA displays on the primary flight display and the head up display. Any training given on the use of an AoA indicator during the research studies or experiments is also included for review
Conservative treatment of Angle Class III malocclusion with anterior crossbite
Directory of Open Access Journals (Sweden)
João Hélder Ferreira de Aguiar
2015-08-01
Full Text Available Angle Class III malocclusion is characterized by anteroposterior dental discrepancy which might be associated or not with skeletal changes. Class III molar relationship is associated with vertical or lingually tipped mandibular incisors and a usually concave profile. These characteristics seriously affect facial esthetics and most frequently are the reason why patients seek orthodontic treatment. This case was presented to the committee of the Brazilian Board of Orthodontics and Facial Orthopedics (BBO as part of the requisites to become a BBO Diplomate.
Extended incident-angle dependence formula of sputter yield
International Nuclear Information System (INIS)
We extend a new semi-empirical formula for incident-angle dependence of normalized sputter yield that includes the contribution to sputter yield from the direct knock-out process that was not considered in the previously proposed one. Three parameters included in the new one are estimated for data calculated with ACAT code for D+ ions incident obliquely on C, Fe and W materials in incident-energy regions from several tens of eV to 10 keV. Then, the parameters are expressed with functions of incident energy. The formula with the functions derived well reproduces that using the ACAT data in the whole energy range. (author)
Asymmetric Domain Walls of Small Angle in Soft Ferromagnetic Films
Döring, Lukas; Ignat, Radu
2016-05-01
We focus on a special type of domain wall appearing in the Landau-Lifshitz theory for soft ferromagnetic films. These domain walls are divergence-free S^2-valued transition layers that connect two directions {m_θ^± in S^2} (differing by an angle {2θ}) and minimize the Dirichlet energy. Our main result is the rigorous derivation of the asymptotic structure and energy of such "asymmetric" domain walls in the limit {θ downarrow 0}. As an application, we deduce that a supercritical bifurcation causes the transition from symmetric to asymmetric walls in the full micromagnetic model.
Characterization of zeolites by magic-angle-spinning NMR
International Nuclear Information System (INIS)
Magic-angle-spinning nuclear magnetic resonance (MAS NMR) has been used to study structure defects in TPA/ZSM-5, the dealumination process caused by hydrothermal treatment and acid leaching of zeolites, the influence of Lewis sites upon water as a probe molecule, the boron incorporation into the ZSM-5 framework, and the acid sites and structure defects in SAPO-5. The nuclei under study are 1H, 11B, 27Al, 29Si, and 31P. 24 refs.; 7 figs.; 1 table
Small-angle X-ray scattering of filled rubber
International Nuclear Information System (INIS)
The addition of fillers such as carbon black and silica in rubber shows reinforcement effects, which increase modulus of elasticity, tensile strength, and cracking resistance. The mechanism of the reinforcement has not yet been understood. A filter composes a hierarchical structure in rubber, where primary particles form aggregates and the aggregates from agglomerates. The structures of the aggregates and agglomerates, on a size of 100 μm∼10 μm, are considered to be the origins of the reinforcement. A two-dimensional ultra-small-angle x-ray scattering (2D-USAXS) system is a promising tool for the observation of the structural change on a size of 100 nm∼10 μm and has been installed in the SPring-8 storage ring. The combination of 2D-USAXS and viscoelastic measurements for styrene-butadiene rubber reveals the relationship between the aggregate structure and reinforcement. The energy dissipation mechanism of fillers will be resolved on the basis of the fluctuation-dissipation theorem from the observation of the fluctuation of fillers by the time-resolved spectra of the coherent microbeam x-ray small angle scattering. (Y.K.)
Correlation function of gravitational deflection angles of light paths
International Nuclear Information System (INIS)
The analytic formula for the correlation function of deflection angles of light paths due to the gravitational lens effect is derived for a simplified model universe. It is shown that the correlation function, which quantitatively expresses the strength of the gravitational lens effect due to inhomogeneities, is characterized by a single parameter. The correlation function is applied to the anisotropy of the cosmic background radiation, and the feature obtained by Sasaki (1988) and by Tomita and Watanabe (1989) is reproduced. The gravitational lens effect on the 'angular diameter distance' is discussed using the correlation function. The strength of the effect is again found to be given by the single parameter. The effect depends strongly on angular scale. 28 refs
Modern Technologies of Open-Angle Glaucoma Surgery
Directory of Open Access Journals (Sweden)
Svetozarskiy S.N.
2014-03-01
Full Text Available Currently, glaucoma surgery has become a major technique. Surgery is a method of choice in open-angle glaucoma, especially in those cases when conservative and laser treatments have no effect, as well as if glaucoma is inaccessible or a patient has low treatment compliance. In this review the authors give the information about the development of main glaucoma surgery directions, such as removal of pupillary block, the anterior chamber fistulization, the reduction of intraocular fluid production. Drainage surgery, its history and modern technical devices have been characterized in detail. The design of drainage devices has been improved towards their size reduction, extension of filtration area and the development of valve mechanisms. Indications for their implementation in open-angle glaucoma treatment, and the factors contributing to a successful treatment have been discussed. There have described early and late complications of microdrainage and paid particular attention to obliteration of developed outflow pathways, being the main problem as they reduce the effect of filtering and draining operations. The authors have presented a number of advanced micro-invasive technologies, both used in clinical practice (Ex-PRESS™ mini-shunt, Trabectome™, iStent, canaloplasty and viscocanalostomy, and those being under clinical study — SOLX Gold Micro-Shunt, CyPass, Hydrus™ Microstent a canalicular scaffold, AqueSys Microfistula Implant. There has been presented the information on design and technology of these devices with their detailed classification based on the differences in their mechanism of action, operative approach type and material used.
Small angle elastic scattering of protons off of spinless nuclei
International Nuclear Information System (INIS)
Elastic differential cross sections and analyzing powers for 800 MeV protons incident on 12C, 40Ca, and 208Pb in the momentum transfer range 20 MeV/c < q < 130 MeV/c have been measured. The data was taken with the High Resolution Spectrometer (HRS) at the Los Alamos Meson Physics Facility. Special delay-line drift chambers with dead regions for the beam to pass through them were used to obtain the data. Through the interference of the Coulomb and nuclear contributions to the differential cross section in the small angle region, the ratio of the real to imaginary part of the forward nuclear amplitude α/sub n/(0) = Ref/sub n/(0)/Imf/sub n/(0) is extracted. The importance of knowing this quantity at lower energies in order to study the differences between relativistic and non-relativistic scattering theories is discussed. 130 refs., 60 figs., 12 tabs
Disorders of the cerebellopontine angle; Klinik der Kleinhirnbrueckenwinkelerkrankungen
Energy Technology Data Exchange (ETDEWEB)
Block, F. [Helios-Kliniken Schwerin (Germany). Neurologische Klinik
2006-03-15
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.) [German] Schwindel, Hoerstoerungen, Affektionen des N. trigeminus oder des N. facialis stellen die wesentlichen und haeufigen Symptome bei Kleinhirnbrueckenwinkelerkrankungen dar. Ipsilaterale Gliedmassenataxie und kontralaterale Hemiparese sprechen fuer eine Mitbeteiligung von Kleinhirn und/oder Hirnstamm, die meist nur bei grossen Prozessen in dieser Region auftreten. Da einige Veraenderungen sich fuer den Patienten unbemerkt entwickeln, ist bei Verdacht eine gezielte klinische Untersuchung dieser Funktionen angezeigt, die durch elektrophysiologische Diagnostik wie z. B. akustisch evozierte Potenziale oder Blinkreflexe untermauert werden kann. Auch wenn natuerlich die kausale Therapie im Vordergrund steht, ist es gar nicht selten notwendig, eine symptomatische Behandlung durchzufuehren. Dies trifft besonders fuer Symptome wie Schwindel oder Gesichtsschmerzen zu. (orig.)
Characterization of porous materials by small-angle scattering
Indian Academy of Sciences (India)
S Mazumder; D Sen; A K Patra
2004-07-01
Characterization of porous materials by small-angle scattering has been extensively pursued for several years now as the pores are often of mesoscopic size and compatible with the length scale accessible by the technique using both neutrons and X-rays as probing radiation. With the availability of ultra small-angle scattering instruments, one can investigate porous materials in the sub-micron length scale. Because of the increased accessible length scale vis-a-vis the multiple scattering effect, conventional data analysis procedures based on single scattering approximation quite often fail. The limitation of conventional data analysis procedures is also pronounced in the case of thick samples and long wavelength of the probing radiation. Effect of multiple scattering is manifested by broadening the scattering profile. Sample thickness for some technologically important materials is often significantly high, as the experimental samples have to replicate all its essential properties in the bulk material. Larger wavelength of the probing radiation is used in some cases to access large length scale and also to minimize the effect of double Bragg reflections.
Analysis of volume holographic storage allowing large-angle illumination
Shamir, Joseph
2005-05-01
Advanced technological developments have stimulated renewed interest in volume holography for applications such as information storage and wavelength multiplexing for communications and laser beam shaping. In these and many other applications, the information-carrying wave fronts usually possess narrow spatial-frequency bands, although they may propagate at large angles with respect to each other or a preferred optical axis. Conventional analytic methods are not capable of properly analyzing the optical architectures involved. For mitigation of the analytic difficulties, a novel approximation is introduced to treat narrow spatial-frequency band wave fronts propagating at large angles. This approximation is incorporated into the analysis of volume holography based on a plane-wave decomposition and Fourier analysis. As a result of the analysis, the recently introduced generalized Bragg selectivity is rederived for this more general case and is shown to provide enhanced performance for the above indicated applications. The power of the new theoretical description is demonstrated with the help of specific examples and computer simulations. The simulations reveal some interesting effects, such as coherent motion blur, that were predicted in an earlier publication.
Influence of Reflectivity and Cloud Cover on the Optimal TiltAngle of Solar Panels
Torres, David J.; Jorge Crichigno
2015-01-01
Determining the optimum angle for a solar panel is important if tracking systems are not used and a tilt angle remains constant. This article determines the sensitivity of the optimum angle to surface reflectivity at different latitudes using a mathematical model that accounts for direct, diffuse and reflected radiation. A quadratic correlation is also developed to compute the optimal angle and maximum energy as a function of latitude and reflectivity. We also seek to determine how sensitive ...
Flight Calibration of the LROC Narrow Angle Camera
Humm, D. C.; Tschimmel, M.; Brylow, S. M.; Mahanti, P.; Tran, T. N.; Braden, S. E.; Wiseman, S.; Danton, J.; Eliason, E. M.; Robinson, M. S.
2016-04-01
Characterization and calibration are vital for instrument commanding and image interpretation in remote sensing. The Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC) takes 500 Mpixel greyscale images of lunar scenes at 0.5 meters/pixel. It uses two nominally identical line scan cameras for a larger crosstrack field of view. Stray light, spatial crosstalk, and nonlinearity were characterized using flight images of the Earth and the lunar limb. These are important for imaging shadowed craters, studying ˜1 meter size objects, and photometry respectively. Background, nonlinearity, and flatfield corrections have been implemented in the calibration pipeline. An eight-column pattern in the background is corrected. The detector is linear for DN = 600--2000 but a signal-dependent additive correction is required and applied for DNdetector temperature and dark level was developed to command dark level offset. This avoids images with a cutoff at DN=0 and minimizes quantization error in companding. Absolute radiometric calibration is derived from comparison of NAC images with ground-based images taken with the Robotic Lunar Observatory (ROLO) at much lower spatial resolution but with the same photometric angles.
Remote control of restricted sets of operations Teleportation of Angles
Huelga, S F; Vaccaro, J A
2002-01-01
We study the remote implementation of a unitary transformation on a qubit. We show the existence of non-trivial protocols (i.e., using less resources than bidirectional state teleportation) which allow the perfect remote implementation of certain continuous sets of quantum operations. We prove that, up to a local change of basis, only two subsets exist that can be implemented remotely with a non-trivial protocol: Arbitrary rotations around a fixed direction $\\vec{n}$ and rotations by a fixed angle around an arbitrary direction lying in a plane orthogonal to $\\vec{n}$. The overall classical information and distributed entanglement cost required for the remote implementation depends on whether it is a priori known to which of the two teleportable subsets the transformation belongs to. If it is so, the optimal protocol consumes one e-bit of entanglement and one c-bit in each direction. If the subset is not known, two e-bits of entanglement need to be consumed while the classical channel becomes asymmetric, two c...
Yoo, Won-gyu
2014-01-01
[Purpose] This study compared the forward head angle and the lumbar flexion and rotation angles of computer workers using routine and fixed computer workstations. [Subjects] Ten male workers voluntarily consented to participate in the study. [Methods] A 3-D motion analysis system was used to measure the angles of the forward head and lumbar flexion. All subjects performed computer work for 30 minutes using both types of workstation. [Results] When working at the fixed workstation, the forward...
Numerical simulation of asymmetric particle precipitation by pitch angle diffusion
Thorne, Richard M.; Abel, Robert W.; Summers, Danny
1996-11-01
A numerical simulation code is developed to evaluate the loss rate of particles trapped in a mirror magnetic field geometry with asymmetric loss cones. The one-dimensional model can accommodate particle diffusion at any prescribed rate and loss cones of any prescribed sizes, and it incorporates the important effect of atmospheric backscattering. Numerical solutions for the loss cone particle distribution function calculated for the case of equal loss cones provide an acceptable simulation of the well-known modified Bessel function solution. The code provides the first quantitative solutions for any specified rate of pitch angle scattering for the general case of arbitrary asymmetry in loss cone size. In the case of weak or moderate diffusion the ratio of particle precipitation fluxes into the two loss cones can provide a sensitive measurement of the rate of particle scattering, but to utilize this important diagnostic property, one must also have information on the fraction of particles that are backscattered from the atmosphere.
Xia, Run-Qiu; Wang, Xia; Jin, Wei-Qi; Liang, Jian-An
2015-10-01
Linear polarizer-based polarimeters that measure the degree of linear polarization (DoLP) and the angle of polarization (AoP) were considered in this study. Variances of DoLP and AoP of the region of interest (ROI) to be measured were analyzed using a statistical method. To simplify the calculation, only additive noise and shot noise were considered. Optimized combinations of the polarizers that can minimize the variances of DoLP and AoP were determined by investigating the variances of different polarizer combinations. Several regularities were found when analyzing the data obtained from the optimized combinations. Some variables in the combinations are inversely proportional to the cube or square root of the signal-to-noise ratio of the output signals from sensors without polarizer filtering, and these variables are functions of the DoLP of the ROI to be measured.
Angles of inclination and anteversion in hip dysplasia in the dog
International Nuclear Information System (INIS)
The angles of inclination and anteversion of the femoral head and neck were measured on 150 limbs of 75 dogs. These hip angles were compared with pathoanatomic and radiographic scores of hip dysplasia. There was a minimal difference between dysplastic and healthy dogs in the angles of inclination and anteversion. It was concluded that in this series of dogs, hip angles did not have a part in the development of hip dysplasia
Apples, oranges, and angles: Comparative kinematic analysis of disparate limbs.
Gatesy, Stephen M; Pollard, Nancy S
2011-08-01
Tetrapod limbs exhibit diverse postures and movements during terrestrial locomotion. As with morphological traits, the history of kinematic evolution should be accessible to reconstruction through analysis of limb motion patterns in a phylogenetic framework. However, the angular data comprising most kinematic descriptions appear to suffer from limitations that preclude meaningful comparison among disparate species. Using simple planar models, we discuss how geometric constraints render joint and elevation angles independent of neither morphology, degree of crouch, nor one another during the stance phase of locomotion. The implicit null hypothesis of potential similarity is invalidated because angular data are not viably transferable among limbs of dissimilar proportion and/or degree of crouch. Overlooking or dismissing the effect of constraints on angular parameterization hampers efforts to quantitatively elucidate the evolution of locomotion. We advocate a search for alternative methods of measuring limb movement that can decouple intersegmental coordination from morphology and posture. PMID:21600220
Small-angle scattering study of Aspergillus awamori glycoprotein glucoamylase
International Nuclear Information System (INIS)
Glucoamylase from fungus Aspergillus awamori is glycoside hydrolase that catalyzes the hydrolysis of α-1,4- and α-1,6-glucosidic bonds in glucose polymers and oligomers. This glycoprotein consists of a catalytic domain and a starch-binding domain connected by an O-glycosylated polypeptide chain. The conformation of the linker, the relative arrangement of the domains, and the structure of the full-length enzyme are unknown. The structure of the recombinant glucoamylase GA1 was studied by molecular modelling and small-angle neutron scattering (SANS) methods. The experimental SANS data provide evidence that glucoamylase exists as a monomer in solution and contains a glycoside component, which makes a substantial contribution to the scattering. The model of full-length glucoamylase, which was calculated without taking into account the effect of glycosylation, is consistent with the experimental data and has a radius of gyration of 33.4 ± 0.6 Å
Small-angle scattering study of Aspergillus awamori glycoprotein glucoamylase
Schmidt, A. E.; Shvetsov, A. V.; Kuklin, A. I.; Lebedev, D. V.; Surzhik, M. A.; Sergeev, V. R.; Isaev-Ivanov, V. V.
2016-01-01
Glucoamylase from fungus Aspergillus awamori is glycoside hydrolase that catalyzes the hydrolysis of α-1,4- and α-1,6-glucosidic bonds in glucose polymers and oligomers. This glycoprotein consists of a catalytic domain and a starch-binding domain connected by an O-glycosylated polypeptide chain. The conformation of the linker, the relative arrangement of the domains, and the structure of the full-length enzyme are unknown. The structure of the recombinant glucoamylase GA1 was studied by molecular modelling and small-angle neutron scattering (SANS) methods. The experimental SANS data provide evidence that glucoamylase exists as a monomer in solution and contains a glycoside component, which makes a substantial contribution to the scattering. The model of full-length glucoamylase, which was calculated without taking into account the effect of glycosylation, is consistent with the experimental data and has a radius of gyration of 33.4 ± 0.6 Å.
Leptogenesis from Oscillations of Heavy Neutrinos with Large Mixing Angles
Drewes, Marco; Gueter, Dario; Klaric, Juraj
2016-01-01
The extension of the Standard Model by heavy right-handed neutrinos can simultaneously explain the observed neutrino masses via the seesaw mechanism and the baryon asymmetry of the Universe via leptogenesis. If the mass of the heavy neutrinos is below the electroweak scale, they may be found at LHCb, BELLE II, the proposed SHiP experiment or a future high-energy collider. In this mass range, the baryon asymmetry is generated via $CP$-violating oscillations of the heavy neutrinos during their production. We study the generation of the baryon asymmetry of the Universe in this scenario from first principles of non-equilibrium quantum field theory, including spectator processes and feedback effects. We eliminate several uncertainties from previous calculations and find that the baryon asymmetry of the Universe can be explained with larger heavy neutrino mixing angles, increasing the chance for an experimental discovery. For the limiting cases of fast and strongly overdamped oscillations of right-handed neutrinos,...
Small-angle scattering study of Aspergillus awamori glycoprotein glucoamylase
Energy Technology Data Exchange (ETDEWEB)
Schmidt, A. E., E-mail: schmidt@omrb.pnpi.spb.ru; Shvetsov, A. V. [National Research Center “Kurchatov Institute”, Konstantinov Petersburg Nuclear Physics Institute (Russian Federation); Kuklin, A. I. [Joint Institute for Nuclear Research (Russian Federation); Lebedev, D. V.; Surzhik, M. A.; Sergeev, V. R.; Isaev-Ivanov, V. V. [National Research Center “Kurchatov Institute”, Konstantinov Petersburg Nuclear Physics Institute (Russian Federation)
2016-01-15
Glucoamylase from fungus Aspergillus awamori is glycoside hydrolase that catalyzes the hydrolysis of α-1,4- and α-1,6-glucosidic bonds in glucose polymers and oligomers. This glycoprotein consists of a catalytic domain and a starch-binding domain connected by an O-glycosylated polypeptide chain. The conformation of the linker, the relative arrangement of the domains, and the structure of the full-length enzyme are unknown. The structure of the recombinant glucoamylase GA1 was studied by molecular modelling and small-angle neutron scattering (SANS) methods. The experimental SANS data provide evidence that glucoamylase exists as a monomer in solution and contains a glycoside component, which makes a substantial contribution to the scattering. The model of full-length glucoamylase, which was calculated without taking into account the effect of glycosylation, is consistent with the experimental data and has a radius of gyration of 33.4 ± 0.6 Å.
Aerodynamic performance of wind turbine under different yaw angles
DEFF Research Database (Denmark)
Shi, Yali; Zuo, Hongmei; Yang, Hua;
2015-01-01
is set as 5×10-6 m to ensure the first dimensionless size near the wall Y+<0.5 on the wall, the 2 numbers of grids are determined by the error of axial load on the airfoil in the 60% section of blades, which respectively are 6 572 451 and 2 961 385. The aerodynamic performance of models under rated...... are drawn. The distributions of pressure coefficients along the airfoil chord in different blade sections calculated by CFD method are in good agreement with the experimental measurements, and the error on the suction surface of airfoil is mainly caused by stall separation occurring on the pressure...... surface of airfoil. With the increasing of yaw angle, the pressure coefficients of the suction side are increasing and the location of minimum pressure coefficient moves to airfoil trailing edge slightly. For the pressure side, the pressure coefficients increase at first and then decrease, and the...
Optimal VLF Parameters for Pitch Angle Scattering of Trapped Electrons
Albert, J. M.; Inan, U. S.
2001-12-01
VLF waves are known to determine the lifetimes of energetic radiation belt electrons in the inner radiation belt and slot regions. Artificial injection of such waves from ground- or space-based transmitters may thus be used to affect the trapped electron population. In this paper, we seek to determine the optimal parameters (frequency and wave normal angle) of a quasi-monochromatic VLF wave using bounce-averaged quasi-linear theory. We consider the cumulative effects of all harmonic resonances and determine the diffusion rates of particles with selected energies on particular L-shells. We also compare the effects of the VLF wave to diffusion driven by other whistler-mode waves (plasmaspheric hiss, lightning, and VLF transmitters). With appropriate choice of the wave parameters, it may be possible to substantially reduce the lifetime of selected classes of particles.
Remote Sensing of Sea State by the Brewsters Angle Technique
Directory of Open Access Journals (Sweden)
P.V. Sathe
1990-04-01
Full Text Available The extent of plane polarised light resulting from Brewsters reflection from the wide-roughened sea surface is studied for various sea states on the assumption that the incident light on the air-sea interface is unpolarised. The sea states associated with different wind speeds are simulated using the Cox and Munk 'wind speed-wave slope' law and the Gaussian distribution of wave-slopes. The spatial distribution of plane polarised component of diffuse reflected light is also studied with a view to exploring possibilities of using this parameter for remote sensing of sea state from a sensor viewing the sea surface through an appropriate polaroid. The results show that the plane polarised fraction of reflected light as received in a given look angle can be directly related to the prevailing sea state and can be used as a convenient parameter for remote sensing of sea state. The scope and limitations of the method proposed are discussed.
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
Glancing-angle scattering of fast ions at crystal surfaces
International Nuclear Information System (INIS)
Glancing angle scattering of fast ions from a single crystal surface is a novel technique to study ion-surface interaction. Results of recent studies of ion-surface interaction are reviewed for ions with velocities faster than the Fermi velocity of solid. For the ions with velocities less than the Fermi velocity of target valence electrons the ion-surface interaction shows a new aspect where only the valence electrons of target solid participate in the stopping processes. It will show that the position-dependent stopping power of a surface for these ions governed by the elastic collisions of valence electrons and the ions. A method is proposed from this position-dependent stopping power to derived the electron density distribution averaged over the plane parallel to the surface. (author)
Shape measurement of aspheric plastic lens with large angle
Institute of Scientific and Technical Information of China (English)
Dagang Huang; Heng Zhang; Shah-Rong Lee; Baoguang Wang
2005-01-01
@@ In this paper, according to the features of easy distortion and scratch for aspheric plastic lens, a noncontact measuring method is raised to test error in shape of the lens. Namely, the distance between a template and its image reflected with tested lens can be measured in nearly the vertical direction of the lens axis when the two-dimensional (2D) template is put near the measured surface. Then, the outline of the central cross-section could be obtained by calculating and curve fitting. Furthermore, three-dimensional (3D) surface can be imitated through rotating the component. A new fitting method of drift measurement is presented to prevent reducing precision when the lens and the template are fixed. The template is adjusted according to the position of the lens. The measurement precision is in the order of magnitued of sub-microns. Rotationally symmetric convex aspheric surface with any angle can be measured by this method.
Glancing-angle scattering of fast ions at crystal surfaces
Energy Technology Data Exchange (ETDEWEB)
Mannami, Michihiko; Narumi, Kazumasa; Katoh, Humiya; Kimura, Kenji [Kyoto Univ. (Japan). Faculty of Engineering
1997-03-01
Glancing angle scattering of fast ions from a single crystal surface is a novel technique to study ion-surface interaction. Results of recent studies of ion-surface interaction are reviewed for ions with velocities faster than the Fermi velocity of solid. For the ions with velocities less than the Fermi velocity of target valence electrons the ion-surface interaction shows a new aspect where only the valence electrons of target solid participate in the stopping processes. It will show that the position-dependent stopping power of a surface for these ions governed by the elastic collisions of valence electrons and the ions. A method is proposed from this position-dependent stopping power to derived the electron density distribution averaged over the plane parallel to the surface. (author)
Photoproduction of Pseudoscalar Mesons off Nuclei at Forward Angles
Gevorkyan, S; Gan, L; Larin, I; Khandaker, M
2009-01-01
With the advent of new photon tagging facilities and novel experimental technologies it has become possible to perform photoproduction cross section measurements of pseudoscalar mesons on nuclei with a percent level accuracy. The extraction of the radiative decay widths from these measurements at forward angles is done by the Primakoff method, which requires theoretical treatment of all processes participating in these reactions at the same percent level. In this work we review the theoretical approach to meson photoproduction amplitudes in the electromagnetic and strong fields of nuclei at forward direction. The most updated description of these processes are presented based on the Glauber theory of multiple scattering. In particular, the effects of final state interactions, corrections for light nuclei, and photon shadowing in nuclei are discussed.
Efficacy of goniosynechialysis for advanced chronic angle-closure glaucoma
Directory of Open Access Journals (Sweden)
Qing G
2012-10-01
Full Text Available Guoping Qing,1,2 Ningli Wang,1 Dapeng Mu11Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Lab, Beijing, China; 2State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, ChinaPurpose: To evaluate the intraocular pressure (IOP-lowering efficacy of goniosynechialysis (GSL for advanced chronic angle-closure glaucoma (CACG using a simplified slit-lamp technique.Patients and methods: Patients with CACG with one severely affected eye with best-corrected visual acuity below 20/200 and a mildly or functionally unaffected fellow eye were enrolled in this study. All patients underwent ophthalmologic examinations including measurement of visual acuity, best-corrected visual acuity, and IOP; biomicroscopy; specular microscopy; fundus examination; and gonioscopy followed by anterior chamber paracentesis and GSL for nasal peripheral anterior synechiae in the eye with severe CACG.Results: Thirty patients (18 men, 12 women were identified as having CACG with an initial mean IOP of 47.1 ± 6.7 mmHg (range 39–61 mmHg in the severely affected eye. One week after GSL, the mean IOP of the treated eyes decreased to 19.3 ± 2.8 mmHg (range 14–26 mmHg without antiglaucoma medication (average decrease 27.7 ± 6.5 mmHg; range 16–41 mmHg, which was significant (P < 0.00001 compared with baseline. After an average follow-up period of 36.6 ± 1.0 months (range 35–38 months, the mean IOP stabilized at 17.4 ± 2.2 mmHg (range 12–21 mmHg. The nasal angle recess did not close again in any one of the patients during the follow-up period. The average significant (P < 0.00001 decrease in corneal endothelial cell density in the treated eyes was 260 ± 183 cells/mm2 (range 191–328 cells/mm2.Conclusions: Anterior chamber paracentesis and GSL lowers IOP in advanced CACG, though it may lead to mild corneal endothelial cell loss
Structural studies of ferrofluids by small-angle neutron scattering
International Nuclear Information System (INIS)
Ferrofluids or magnetic fluids - colloidal suspensions of single domain magnetic particles of about 100 A in diameter, stabilized with a surfactant shell in a suitable liquid carrier - are of current interest. One of the most powerful techniques involved is the small-angle neutron scattering (SANS). This is particularly suited to the study of magnetic colloids, because of the peculiar features of their magnetic interaction which enable the determination of the colloidal dispersion structure under a wide variety of experimental conditions. We present our investigations on ferrofluids performed on the YuMO small-angle neutron scattering diffractometer in function at the IBR-2 pulsed reactor at the Frank Laboratory of Neutron Physics of the Joint Institute for Nuclear Research, Dubna, Russia and on the SANS diffractometer installed at WWR-SM steady reactor at the Research Institute for Solid State Physics and Optics, Budapest, Hungary. There can be investigated the structure of the particle, the aggregation phenomena, the magnetic liquid dynamics, particle-surfactant interaction, surfactant liquid-base interaction and structure, magnetic behavior of the samples. Ferrofluids exhibit a remarkably rich variety of behaviors and their study has been and still remains very active, since it is considered to open new technological frontiers. These materials are important for technological application as for their intrinsic physical properties, to understand and to improve the interesting macroscopic level, and to find how this structure is influenced by the action of certain parameters. Due to specific properties in a magnetic field they have been actively used in a lot of industrial, technical, as well as in biological and medical applications. (authors)
High-resolution NMR of anisotropic samples with spinning away from the magic angle
Energy Technology Data Exchange (ETDEWEB)
Sakellariou, Dimitris; Meriles, Carlos A.; Martin, Rachel W.; Pines, Alexander
2003-03-31
High-resolution NMR of samples in the solid state is typically performed under mechanical sample spinning around an axis that makes an angle, called the magic angle, of 54.7 degrees with the static magnetic field. There are many cases in which geometrical and engineering constraints prevent spinning at this specific angle. Implementations of in-situ and ex-situ magic angle field spinning might be extremely demanding because of the power requirements or an inconvenient sample size or geometry. Here we present a methodology based on switched angle spinning between two angles, none of which is the magic angle, which provide both isotropic and anisotropic information. Using this method, named Projected Magic Angle Spinning, we were able to obtain resolved isotropic chemical shifts in spinning samples where the broadening is mostly inhomogeneous.
Extreme value statistics of CMB lensing deflection angles
Merkel, Philipp M
2015-01-01
The smaller the angular scales on which the anisotropies of the cosmic microwave background (CMB) are probed the more important their distortion due to gravitational lensing becomes. Here we investigate the maxima and minima of the CMB lensing deflection field using general extreme value statistics. Since general extreme value statistics applies to uncorrelated data in first place we consider appropriately low-pass filtered deflection maps. Besides the suppression of correlations filtering is required for another reason: The lensing field itself is not directly observable but needs to be (statistically) reconstructed from the lensed CMB by means of a quadratic estimator. This reconstruction, though, is noise dominated and therefore requires smoothing, too. In idealized Gaussian realizations as well as in realistically reconstructed data we find that both maxima and minima of the deflection angle components follow consistently a general extreme value distribution of Weibull-type. However, its shape, location a...