WorldWideScience

Sample records for inadvance quad angles

  1. QUAD TAG MODULE

    International Nuclear Information System (INIS)

    Shiino, K.; Maruyama, K.

    1981-08-01

    Electronic circuits called QUAD TAG MODULE were developed and constructed, which were of exclusive use for signals from scintillation counter hodoscope of the photon tagging system. The circuit has functions of amplifiers, discriminators, and strobed coincidences in one NIM module. A description on functions and specifications of the module is given. (author)

  2. Quad Rotorcraft Control Vision-Based Hovering and Navigation

    CERN Document Server

    García Carrillo, Luis Rodolfo; Lozano, Rogelio; Pégard, Claude

    2013-01-01

    Quad-Rotor Control develops original control methods for the navigation and hovering flight of an autonomous mini-quad-rotor robotic helicopter. These methods use an imaging system and a combination of inertial and altitude sensors to localize and guide the movement of the unmanned aerial vehicle relative to its immediate environment. The history, classification and applications of UAVs are introduced, followed by a description of modelling techniques for quad-rotors and the experimental platform itself. A control strategy for the improvement of attitude stabilization in quad-rotors is then proposed and tested in real-time experiments. The strategy, based on the use of low-cost components and with experimentally-established robustness, avoids drift in the UAV’s angular position by the addition of an internal control loop to each electronic speed controller ensuring that, during hovering flight, all four motors turn at almost the same speed. The quad-rotor’s Euler angles being very close to the origin, oth...

  3. USGS Digital Orthophoto Quad (DOQ) Metadata

    Data.gov (United States)

    Minnesota Department of Natural Resources — Metadata for the USGS DOQ Orthophoto Layer. Each orthophoto is represented by a Quarter 24k Quad tile polygon. The polygon attributes contain the quarter-quad tile...

  4. USGS Digital Orthophoto Quad (DOQ) - 3 meter

    Data.gov (United States)

    Minnesota Department of Natural Resources — These data files are a collection of the USGS standard DOQs that have been resampled to a 3-meter cell resolution and mosaiced into quad format vs quarter quad...

  5. Converting skeletal structures to quad dominant meshes

    DEFF Research Database (Denmark)

    Bærentzen, Jakob Andreas; Misztal, Marek Krzysztof; Welnicka, Katarzyna

    2012-01-01

    We propose the Skeleton to Quad-dominant polygonal Mesh algorithm (SQM), which converts skeletal structures to meshes composed entirely of polar and annular regions. Both types of regions have a regular structure where all faces are quads except for a single ring of triangles at the center of eac...

  6. The impact of ΛCDM substructure and baryon-dark matter transition on the image positions of quad galaxy lenses

    Science.gov (United States)

    Gomer, Matthew R.; Williams, Liliya L. R.

    2018-04-01

    The positions of multiple images in galaxy lenses are related to the galaxy mass distribution. Smooth elliptical mass profiles were previously shown to be inadequate in reproducing the quad population. In this paper, we explore the deviations from such smooth elliptical mass distributions. Unlike most other work, we use a model-free approach based on the relative polar image angles of quads, and their position in 3D space with respect to the fundamental surface of quads (FSQ). The FSQ is defined by quads produced by elliptical lenses. We have generated thousands of quads from synthetic populations of lenses with substructure consistent with Lambda cold dark matter (ΛCDM) simulations, and found that such perturbations are not sufficient to match the observed distribution of quads relative to the FSQ. The result is unchanged even when subhalo masses are increased by a factor of 10, and the most optimistic lensing selection bias is applied. We then produce quads from galaxies created using two components, representing baryons and dark matter. The transition from the mass being dominated by baryons in inner radii to being dominated by dark matter in outer radii can carry with it asymmetries, which would affect relative image angles. We run preliminary experiments using lenses with two elliptical mass components with non-identical axial ratios and position angles, perturbations from ellipticity in the form of non-zero Fourier coefficients a4 and a6, and artificially offset ellipse centres as a proxy for asymmetry at image radii. We show that combination of these effects is a promising way of accounting for quad population properties. We conclude that the quad population provides a unique and sensitive tool for constraining detailed mass distribution in the centres of galaxies.

  7. Quad-copter UAV BLDC Motor Control: Linear v/s non-linear control maps

    Directory of Open Access Journals (Sweden)

    Deep Parikh

    2015-08-01

    Full Text Available This paper presents some investigations and comparison of using linear versus non-linear static motor-control maps for the speed control of a BLDC (Brush Less Direct Current motors used in quad-copter UAV (Unmanned Aerial Vehicles. The motor-control map considered here is the inverse of the static map relating motor-speed output to motor-voltage input for a typical out-runner type Brushless DC Motors (BLDCM.  Traditionally, quad-copter BLDC motor speed control uses simple linear motor-control map defined by the motor-constant specification. However, practical BLDC motors show non-linear characteristic, particularly when operated across wide operating speed-range as is commonly required in quad-copter UAV flight operations. In this paper, our investigations to compare performance of linear versus non-linear motor-control maps are presented. The investigations cover simulation-based and experimental study of BLDC motor speed control systems for  quad-copter vehicle available. First the non-linear map relating rotor RPM to motor voltage for quad-copter BLDC motor is obtained experimentally using an optical speed encoder. The performance of the linear versus non-linear motor-control-maps for the speed control are studied. The investigations also cover study of time-responses for various standard test input-signals e.g. step, ramp and pulse inputs, applied as the reference speed-commands. Also, simple 2-degree of freedom test-bed is developed in our laboratory to help test the open-loop and closed-loop experimental investigations. The non-linear motor-control map is found to perform better in BLDC motor speed tracking control performance and thereby helping achieve better quad-copter roll-angle attitude control.

  8. Connectivity editing for quad-dominant meshes

    KAUST Repository

    Peng, Chihan

    2013-08-01

    We propose a connectivity editing framework for quad-dominant meshes. In our framework, the user can edit the mesh connectivity to control the location, type, and number of irregular vertices (with more or fewer than four neighbors) and irregular faces (non-quads). We provide a theoretical analysis of the problem, discuss what edits are possible and impossible, and describe how to implement an editing framework that realizes all possible editing operations. In the results, we show example edits and illustrate the advantages and disadvantages of different strategies for quad-dominant mesh design. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and John Wiley & Sons Ltd.

  9. A novel bit-quad-based Euler number computing algorithm.

    Science.gov (United States)

    Yao, Bin; He, Lifeng; Kang, Shiying; Chao, Yuyan; Zhao, Xiao

    2015-01-01

    The Euler number of a binary image is an important topological property in computer vision and pattern recognition. This paper proposes a novel bit-quad-based Euler number computing algorithm. Based on graph theory and analysis on bit-quad patterns, our algorithm only needs to count two bit-quad patterns. Moreover, by use of the information obtained during processing the previous bit-quad, the average number of pixels to be checked for processing a bit-quad is only 1.75. Experimental results demonstrated that our method outperforms significantly conventional Euler number computing algorithms.

  10. Usefulness of a Rugby-shaped hohlraum in a Laser M'egaJoule (LMJ) 40-quad configuration

    Science.gov (United States)

    Malinie, G.; Vandenboomgaerde, M.; Bastian, J.; Galmiche, D.; Laffite, S.; Liberatore, S.

    2007-11-01

    The LMJ setup will consist of 60 quads in a 3-cone configuration, at angles 33.2^o, 49^o and 59.5^o. First ignition attempts in indirect drive are planned to be made on the way to the completion of the full facility, with only 40 quads in a 2-cone configuration, at angles 33.2^o and 49^o. By analytic considerations, we show that in a 40-quad configuration, the angular location of the hohlraum outer irradiating ring, as seen from the capsule, must be closer to the laser entrance hole than with the full LMJ. The use of a Rugby-shaped hohlraum instead of a cylinder therefore allows to keep a correct symmetry while reducing the wall surface, which improves the global energetic efficiency of the target. Simplified 2D numerical simulations of Rugby hohlraums are presented, achieving a yield of about 30 MJ with our 1.215 mm-radius, CH-uniform-ablator capsule. These results suggests this kind of hohlraum might be an interesting candidate for 40-quad ignition experiments. Work on optimizing the present design and refining the numerical simulations is currently pursued.

  11. Rilievi in sella a un quad

    Directory of Open Access Journals (Sweden)

    Fulvio Bernardini

    2013-12-01

    Full Text Available Renewable energy—including biomass, geo- thermal, hydroelectric,wind and solar—is big business in Italy. Solar farms able toproduce 1 MW or more of nominal power are considered “large.”Before installing such a PV plant, an acc urate topographical surveyof the ground is required. Giuseppe Greco is known in Italyas an expert in surv eying areas that are extensive and difficult toacc ess. This is because he works with the help of a quad all-terr ainvehicle (AT V, a Segway personal transporter and a personal electricrobotic cart for moving his equipment.

  12. Flocking of quad-rotor UAVs with fuzzy control.

    Science.gov (United States)

    Mao, Xiang; Zhang, Hongbin; Wang, Yanhui

    2018-03-01

    This paper investigates the flocking problem of quad-rotor UAVs. Considering the actual situations, we derived a new simplified quad-rotor UAV model which is more reasonable. Based on the model, the T-S fuzzy model of attitude dynamic equation and the corresponding T-S fuzzy feedback controller are discussed. By introducing a double-loop control construction, we adjust its attitude to realize the position control. Then a flocking algorithm is proposed to achieve the flocking of the quad-rotor UAVs. Compared with the flocking algorithm of the mass point model, we dealt with the collision problem of the quad-rotor UAVs. In order to improve the airspace utilization, a more compact configuration called quasi e-lattice is constructed to guarantee the compact flight of the quad-rotor UAVs. Finally, numerical simulations are provided to illustrate the effectiveness of the obtained theoretical results. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  13. Quad-rotor flight path energy optimization

    Science.gov (United States)

    Kemper, Edward

    Quad-Rotor unmanned areal vehicles (UAVs) have been a popular area of research and development in the last decade, especially with the advent of affordable microcontrollers like the MSP 430 and the Raspberry Pi. Path-Energy Optimization is an area that is well developed for linear systems. In this thesis, this idea of path-energy optimization is extended to the nonlinear model of the Quad-rotor UAV. The classical optimization technique is adapted to the nonlinear model that is derived for the problem at hand, coming up with a set of partial differential equations and boundary value conditions to solve these equations. Then, different techniques to implement energy optimization algorithms are tested using simulations in Python. First, a purely nonlinear approach is used. This method is shown to be computationally intensive, with no practical solution available in a reasonable amount of time. Second, heuristic techniques to minimize the energy of the flight path are tested, using Ziegler-Nichols' proportional integral derivative (PID) controller tuning technique. Finally, a brute force look-up table based PID controller is used. Simulation results of the heuristic method show that both reliable control of the system and path-energy optimization are achieved in a reasonable amount of time.

  14. Australian quad bike fatalities: what is the economic cost?

    Science.gov (United States)

    Lower, Tony; Pollock, Kirrily; Herde, Emily

    2013-04-01

    To determine the economic costs associated with all quad bike-related fatalities in Australia, 2001 to 2010. A human capital approach to establish the economic costs of quad bike related fatalities to the Australian economy. The model included estimates on loss of earnings due to premature death and direct costs based on coronial records for ambulance, police, hospital, premature funeral, coronial and work safety authority investigation, and death compensation costs. All costs were calculated to 2010 dollars. The estimated total economic cost associated with quad bike fatalities over this period was $288.1 million, with an average cost for each fatality of $2.3 million. When assessing the average cost of incidents between age cohorts, those aged 25-34 years had the lowest number of fatalities but had the highest average cost ($4.2 million). Quad bike fatalities have a significant economic impact on Australian society that is increasing. Implications : Given the high cost to society, interventions to address quad bike fatalities have the potential to be highly cost-effective. Such interventions should focus on design approaches to improve the safety of quad bikes in terms of stability and protection in the event of a rollover. Additionally, relevant policy (e.g. no children under 16 years riding quads, no passengers) and intervention approaches (e.g. training and use of helmets) must also support the design modifications. © 2013 The Authors. ANZJPH © 2013 Public Health Association of Australia.

  15. Quad Ropes: Immutable, Declarative Arrays with Parallelizable Operations

    DEFF Research Database (Denmark)

    Biermann, Florian; Sestoft, Peter

    2017-01-01

    , they allow for fast concatenation and dynamic task-based parallelism and are well suited to represent sparse arrays. We describe their operational semantics and evaluate the performance of individual functions on quad ropes as well as declarative algorithms that use our quad rope implementation....... to let users choose between different array-like data structures. Instead, one should use the same, somewhat performance-robust, representation for every programming task. Quad ropes roughly retain array efficiency, as long as programmers express their programs using high-level constructs. Moreover...

  16. Preliminary Analysis of Chinese GF-3 SAR Quad-Polarization Measurements to Extract Winds in Each Polarization

    Directory of Open Access Journals (Sweden)

    Lin Ren

    2017-11-01

    Full Text Available This study analyzed the noise equivalent sigma zero (NESZ and ocean wind sensitivity for Chinese C-band Gaofen-3 (GF-3 quad-polarization synthetic aperture radar (SAR measurements to facilitate further operational wind extraction from GF-3 data. Data from the GF-3 quad-polarization SAR and collocated winds from both NOAA/NCEP Global Forecast System (GFS atmospheric model and National Data Buoy Center (NDBC buoys were used in the analysis. For NESZ, the co-polarization was slightly higher compared to the cross-polarization. Regarding co-polarization and cross-polarization, NESZ was close to RadarSAT-2 and Sentinel-1 A. Wind sensitivity was analyzed by evaluating the dependence on winds in terms of normalized radar cross-sections (NRCS and polarization combinations. The closest geophysical model function (GMF and the polarization ratio (PR model to GF-3 data were determined by comparing data and the model results. The dependence of co-polarized NRCS on wind speed and azimuth angle was consistent with the proposed GMF models. The combination of CMOD5 and CMOD5.N was considered to be the closest GMF in co-polarization. The cross-polarized NRCS exhibited a strong linear relationship with moderate wind speeds higher than 4 m·s−1, but a weak correlation with the azimuth angle. The proposed model was considered as the closest GMF in cross-polarization. For polarization combinations, PR and polarization difference (PD were considered. PR increased only with the incidence angle, whereas PD increased with wind speed and varied with azimuth angle. There were three very close PR models and each can be considered as the closest. Preliminary results indicate that GF-3 quad-polarization data are valid and have the ability to extract winds in each polarization.

  17. 40 CFR 81.102 - Metropolitan Quad Cities Interstate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Metropolitan Quad Cities Interstate... Designation of Air Quality Control Regions § 81.102 Metropolitan Quad Cities Interstate Air Quality Control Region. The Metropolitan Quad Cities Interstate Air Quality Control Region (Illinois-Iowa) consists of...

  18. Attitude and Altitude Controller Design for Quad-Rotor Type MAVs

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2013-01-01

    Full Text Available Micro air vehicles (MAVs have a wide application such as the military reconnaissance, meteorological survey, environmental monitoring, and other aspects. In this paper, attitude and altitude control for Quad-Rotor type MAVs is discussed and analyzed. For the attitude control, a new method by using three gyroscopes and one triaxial accelerometer is proposed to estimate the attitude angle information. Then with the approximate linear model obtained by system identification, Model Reference Sliding Mode Control (MRSMC technique is applied to enhance the robustness. In consideration of the relatively constant altitude model, a Linear Quadratic Gaussian (LQG controller is adopted. The outdoor experimental results demonstrate the superior stability and robustness of the controllers.

  19. Accuracy of a real-time surgical navigation system for the placement of quad zygomatic implants in the severe atrophic maxilla: A pilot clinical study.

    Science.gov (United States)

    Hung, Kuo-Feng; Wang, Feng; Wang, Hao-Wei; Zhou, Wen-Jie; Huang, Wei; Wu, Yi-Qun

    2017-06-01

    A real-time surgical navigation system potentially increases the accuracy when used for quad-zygomatic implant placement. To evaluate the accuracy of a real-time surgical navigation system when used for quad zygomatic implant placement. Patients with severely atrophic maxillae were prospectively recruited. Four trajectories for implants were planned, and zygomatic implants were placed using a real-time surgical navigation system. The planned-placed distance deviations at entry (entry deviation)points, exit (exit deviation) points, and angle deviation of axes (angle deviation) were measured on fused operation images. The differences of all the deviations between different groups, classified based on the lengths and locations of implants, were analysed. A P value of implants were placed as planned in 10 patients. The entry deviation, exit deviation and angle deviation were 1.35 ± 0.75 mm, 2.15 mm ± 0.95 mm, and 2.05 ± 1.02 degrees, respectively. The differences of all deviations were not significant, irrespective of the lengths (P = .259, .158, and .914, respectively) or locations of the placed implants (P = .698, .072, and .602, respectively). A real-time surgical navigation system used for the placement of quad zygomatic implants demonstrated a high level of accuracy with only minimal planned-placed deviations, irrespective of the lengths or locations of the implants. © 2017 Wiley Periodicals, Inc.

  20. Shape Memory Alloy Isolation Valves: Public Quad Chart

    Science.gov (United States)

    2017-05-12

    NUMBER (Include area code) 12 May 2017 Briefing Charts 12 April 2017 - 12 May 2017 Shape Memory Alloy Isolation Valves: Public Quad Chart William...spacecraft (15+ yrs) • Shaped memory alloy isolation valves provide an intrinsically safe isolation system that increases lifetime >5x over SOTA and...Shape Memory Alloy Isolation Valves POC: W. Hargus, Ph.D., AFRL/RQRC B-52 Teardrop Antenna Depolymerization WC-130J Leading Edge Erosion Distribution

  1. Explaining National Border Effects in the Quad Food Trade

    OpenAIRE

    Olper, Alessandro; Raimondi, Valentina

    2006-01-01

    Starting from a theoretically consistent gravity model, this paper first provides estimates of bilateral 'border effects' in food trade among Quad countries (Canada, USA, Japan and EU) at the ISIC 4-digit level. Then, it investigates the underlying reasons of border effect, assessing the role played by policy barriers (tariffs and non-tariff barriers) with respect to barriers unrelated to trade policy, such as information related costs and cultural proximity. In contrast with several previous...

  2. MODELING, CONTROL AND NAVIGATION OF AN AUTONOMOUS QUAD-ROTOR HELICOPTER

    Directory of Open Access Journals (Sweden)

    Damir Šoštarić

    2016-06-01

    Full Text Available Autonomous outdoor quad-rotor helicopters increasingly attract the attention of potential researchers. Several structures and configurations have been developed to allow 3D movements. The quadrotor helicopter is made of a rigid cross frame equipped with four rotors. The autonomous quad-rotor architecture has been chosen for this research for its low dimension, good manoeuvrability, simple mechanics and payload capability. This article presents the modelling, control and navigation of an autonomous outdoor quad-rotor helicopter.

  3. FY17 NIF Performance Quad Campaign: laser performance results and conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Di Nicola, J. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mennerat, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Widmayer, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-10-09

    The FY17 NIF Performance Quad Campaign exercised a single quad of NIF (Q45T) at elevated energy to assess the impact of recent improvements to the infrared (1ω) and ultraviolet (3ω) section of the laser on integrated performance.

  4. Design of a Symmetrical Quad-rotor Biplane Tail-Sitter Aircraft without Control Surfaces and Experimental Verification

    Directory of Open Access Journals (Sweden)

    Wang Hongyu

    2018-01-01

    Full Text Available This paper presents the design of a symmetrical quad-rotor biplane tail-sitter VTOL UAV (Vertical Take-off and Landing Unmanned Aerial Vehicle which is composed of four rotors and two symmetrically mounted fixed wings. This aircraft achieves high accuracy in the attitude control and smooth flight mode transition with four rotors rather than the conventional VTOL UAVs using control surfaces. The proposal of angled rotor mounting is adopted to address the issue of insufficient yaw control authority. The layout of symmetrically mounted fixed wings makes the aircraft have capability of rapid bidirectional flight mode transition to improve maneuverability. To validate the performance of the aircraft, simulation and flight experiments are both implemented. These results show that the aircraft has a rapid yaw response under condition of the stable attitude control. In comparative experiment, it is shown that the aircraft is more flexible than other similar configuration of aircrafts. This symmetrical quad-rotor biplane tail-sitter VTOL UAV will have a wide range of potential applications in the military and civilian areas due to its superior performance..

  5. Quad-Rotor Helicopter Autonomous Navigation Based on Vanishing Point Algorithm

    Directory of Open Access Journals (Sweden)

    Jialiang Wang

    2014-01-01

    Full Text Available Quad-rotor helicopter is becoming popular increasingly as they can well implement many flight missions in more challenging environments, with lower risk of damaging itself and its surroundings. They are employed in many applications, from military operations to civilian tasks. Quad-rotor helicopter autonomous navigation based on the vanishing point fast estimation (VPFE algorithm using clustering principle is implemented in this paper. For images collected by the camera of quad-rotor helicopter, the system executes the process of preprocessing of image, deleting noise interference, edge extracting using Canny operator, and extracting straight lines by randomized hough transformation (RHT method. Then system obtains the position of vanishing point and regards it as destination point and finally controls the autonomous navigation of the quad-rotor helicopter by continuous modification according to the calculated navigation error. The experimental results show that the quad-rotor helicopter can implement the destination navigation well in the indoor environment.

  6. Quad-Rotor Unmanned Aerial Vehicle Helicopter Modelling & Control

    Directory of Open Access Journals (Sweden)

    Yogianandh Naidoo

    2011-09-01

    Full Text Available This paper presents the investigation of the modelling and control of a quad-rotor helicopter and forms part of research involving the development of an unmanned aerial vehicle (UAV to be used in search and rescue applications. Quad-rotor helicopters consist of two pairs of counter rotating rotors situated at the ends of a cross, symmetric about the centre of gravity, which coincides with the origin of the reference system used. These rotors provide the predominant aerodynamic forces which act on the rotorcraft, and are modelled using momentum theory as well as blade element theory. From this, one can determine the expected payload capacity and lift performance of the rotorcraft. The Euler-Lagrange method has been used to derive the defining equations of motion of the six degree-of-freedom system. The Lagrangian was obtained by modelling the kinetic and potential energy of the system and the external forces obtained from the aerodynamic analysis. Based on this model, a control strategy was developed using linear PD controllers. A numerical simulation was then conducted using MATLAB® Simulink®. First, the derived model was simulated to investigate the behaviour of the rotorcraft, and then a second investigation was conducted to determine the effectiveness of the implemented control system. The results and findings of these investigations are then presented and discussed.

  7. Impact of a vaccination programme in children vaccinated with ProQuad, and ProQuad-specific effectiveness against varicella in the Veneto region of Italy.

    Science.gov (United States)

    Giaquinto, Carlo; Gabutti, Giovanni; Baldo, Vincenzo; Villa, Marco; Tramontan, Lara; Raccanello, Nadia; Russo, Francesca; Poma, Chiara; Scamarcia, Antonio; Cantarutti, Luigi; Lundin, Rebecca; Perinetti, Emilia; Cornen, Xavier; Thomas, Stéphane; Ballandras, Céline; Souverain, Audrey; Hartwig, Susanne

    2018-03-05

    Monovalent varicella vaccines have been available in the Veneto Region of Italy since 2004. In 2006, a single vaccine dose was added to the immunisation calendar for children aged 14 months. ProQuad®, a quadrivalent measles-mumps-rubella-varicella vaccine, was introduced in May 2007 and used, among other varicella vaccines, until October 2008. This study aimed to evaluate the effectiveness of a single dose of ProQuad, and the population impact of a vaccination program (VP) against varicella of any severity in children who received a first dose of ProQuad at 14 months of age in the Veneto Region, METHODS: All children born in 2006/2007, i.e., eligible for varicella vaccination after ProQuad was introduced, were retrospectively followed through individual-level data linkage between the Pedianet database (varicella cases) and the Regional Immunization Database (vaccination status). The direct effectiveness of ProQuad was estimated as the incidence rate of varicella in ProQuad-vaccinated children aged impact of the VP on varicella was measured by comparing children eligible for the VP to an unvaccinated historical cohort from 1997/1998. The vaccine impact measures were: total effect (the combined effect of ProQuad vaccination and being covered by the Veneto VP); indirect effect (the effect of the VP on unvaccinated individuals); and overall effect (the effect of the VP on varicella in the entire population of the Veneto Region, regardless of their vaccination status). The adjusted direct effectiveness of ProQuad was 94%. The vaccine impact measures total, indirect, and overall effect were 97%, 43%, and 90%, respectively. These are the first results on the effectiveness and impact of ProQuad against varicella; data confirmed its high effectiveness, based on immunological correlates for protection. Direct effectiveness is our only ProQuad-specific measure; all impact measures refer at least partially to the VP and should be interpreted in the context of high vaccine

  8. Trajectory optimization of multiple quad-rotor UAVs in collaborative assembling task

    Directory of Open Access Journals (Sweden)

    Chen Yongbo

    2016-02-01

    Full Text Available A hierarchic optimization strategy based on the offline path planning process and online trajectory planning process is presented to solve the trajectory optimization problem of multiple quad-rotor unmanned aerial vehicles in the collaborative assembling task. Firstly, the path planning process is solved by a novel parallel intelligent optimization algorithm, the central force optimization-genetic algorithm (CFO-GA, which combines the central force optimization (CFO algorithm with the genetic algorithm (GA. Because of the immaturity of the CFO, the convergence analysis of the CFO is completed by the stability theory of the linear time-variant discrete-time systems. The results show that the parallel CFO-GA algorithm converges faster than the parallel CFO and the central force optimization-sequential quadratic programming (CFO-SQP algorithm. Then, the trajectory planning problem is established based on the path planning results. In order to limit the range of the attitude angle and guarantee the flight stability, the optimized object is changed from the ordinary six-degree-of-freedom rigid-body dynamic model to the dynamic model with an inner-loop attitude controller. The results show that the trajectory planning process can be solved by the mature SQP algorithm easily. Finally, the discussion and analysis of the real-time performance of the hierarchic optimization strategy are presented around the group number of the waypoints and the equal interval time.

  9. Expanding Uncertainty Principle to Certainty-Uncertainty Principles with Neutrosophy and Quad-stage Method

    Directory of Open Access Journals (Sweden)

    Fu Yuhua

    2015-03-01

    Full Text Available The most famous contribution of Heisenberg is uncertainty principle. But the original uncertainty principle is improper. Considering all the possible situations (including the case that people can create laws and applying Neutrosophy and Quad-stage Method, this paper presents "certainty-uncertainty principles" with general form and variable dimension fractal form. According to the classification of Neutrosophy, "certainty-uncertainty principles" can be divided into three principles in different conditions: "certainty principle", namely a particle’s position and momentum can be known simultaneously; "uncertainty principle", namely a particle’s position and momentum cannot be known simultaneously; and neutral (fuzzy "indeterminacy principle", namely whether or not a particle’s position and momentum can be known simultaneously is undetermined. The special cases of "certain ty-uncertainty principles" include the original uncertainty principle and Ozawa inequality. In addition, in accordance with the original uncertainty principle, discussing high-speed particle’s speed and track with Newton mechanics is unreasonable; but according to "certaintyuncertainty principles", Newton mechanics can be used to discuss the problem of gravitational defection of a photon orbit around the Sun (it gives the same result of deflection angle as given by general relativity. Finally, for the reason that in physics the principles, laws and the like that are regardless of the principle (law of conservation of energy may be invalid; therefore "certaintyuncertainty principles" should be restricted (or constrained by principle (law of conservation of energy, and thus it can satisfy the principle (law of conservation of energy.

  10. Optimizing Hexapod Robot Reconfiguration using Hexa-Quad Transformation

    Directory of Open Access Journals (Sweden)

    Addie Irawan

    2013-09-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE This paper presents a leg reconfigurable technique to optimize the hexapod robot reconfiguration flexiblity. A hexapod-to-quadruped (Hexa-Quad transformation technique is proposed to optimize hexapod legs on certain situation that need some legs to be disabled as a leg to do other tasks and operations. This proposed method used the factor of center of body (CoB stability in the support polygon and its body shape. The reinitialized leg’s shoulder method is proposed to ensure the support polygon is balanced and confirmed the CoM nearly or at the center. This method is modeled and simulated in a real-time based model of hexapod robot with 4-DOF/leg control architecture. The model is verified in numerical model and presented using separated 3D simulators.

  11. Dynamics Modeling and Control of a Quad-rotor Helicopter

    Science.gov (United States)

    Hossain, Mohammed Raju

    Unmanned Aerial Vehicles (UAVs) have become a promising field of research due to the enormous potential for both military and civilian applications. This thesis focuses on increasing the autonomy of one type of rotary wing UAV; namely a Quad-rotor Helicopter. In this work a detailed mathematical model was introduced for simulation of the dynamics and control of this system. The dynamic model evolved from a simple set of equations, valid only for hovering, to a complex mathematical model with more realistic aerodynamic factors like thrust factor and drag factor. A simple yet precise tool was developed to measure these aerodynamic factors. An intelligent vision based control technique has been proposed for the critical, near-hovering flight of the vehicle. Finally, a platform was developed and a PD controller was implemented with inertial sensors in order to prepare the platform for implementing the vision-based control in the future.

  12. Quad-Band U-Slot Antenna for Mobile Applications

    Directory of Open Access Journals (Sweden)

    R. L. Ruiz

    2006-06-01

    Full Text Available In this paper, two different planar quad-band antennas are designed, modeled, fabricated and measured. Subsequently, the antennas are redesigned using an electromagnetic band gap substrate (EBG. Those new planar antennas operate in four frequency bands: 900 MHz, 1 800 MHz (both GSM, 1 900 MHz (USA and 2 400 to 2 500 MHz (Bluetooth The antenna has four narrow U-shaped slots etched to the patch. Using software, CST Microwave Studio [1], Zeland IE3D [2], and FEMLAB [3], simulations have been carried out to investigate the antenna's performance and characteristics. The antennas designed have been also built and measured to compare the real results with those obtained from the simulations.

  13. Ultra-Low Noise Quad Photoreceiver for Space Based Laser Interferometric Gravity Wave Detection, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to design and develop 2x2 quad p-i-n InGaAs Photoreceivers having the following characteristics: (a) Active area diameter 0.75 mm; (b) Wavelength coverage...

  14. HYBRID COMMUNICATION NETWORK OF MOBILE ROBOT AND QUAD-COPTER

    Directory of Open Access Journals (Sweden)

    Moustafa M. Kurdi

    2017-01-01

    Full Text Available This paper introduces the design and development of QMRS (Quadcopter Mobile Robotic System. QMRS is a real-time obstacle avoidance capability in Belarus-132N mobile robot with the cooperation of quadcopter Phantom-4. The function of QMRS consists of GPS used by Mobile Robot and image vision and image processing system from both robot and quad-copter and by using effective searching algorithm embedded inside the robot. Having the capacity to navigate accurately is one of the major abilities of a mobile robot to effectively execute a variety of jobs including manipulation, docking, and transportation. To achieve the desired navigation accuracy, mobile robots are typically equipped with on-board sensors to observe persistent features in the environment, to estimate their pose from these observations, and to adjust their motion accordingly. Quadcopter takes off from Mobile Robot, surveys the terrain and transmits the processed Image terrestrial robot. The main objective of research paper is to focus on the full coordination between robot and quadcopter by designing an efficient wireless communication using WIFI. In addition, it identify the method involving the use of vision and image processing system from both robot and quadcopter; analyzing path in real-time and avoiding obstacles based-on the computational algorithm embedded inside the robot. QMRS increases the efficiency and reliability of the whole system especially in robot navigation, image processing and obstacle avoidance due to the help and connection among the different parts of the system.

  15. Scoliosis angle

    International Nuclear Information System (INIS)

    Marklund, T.

    1978-01-01

    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.)

  16. Escaping Depressions in LRTS Based on Incremental Refinement of Encoded Quad-Trees

    Directory of Open Access Journals (Sweden)

    Yue Hu

    2017-01-01

    Full Text Available In the context of robot navigation, game AI, and so on, real-time search is extensively used to undertake motion planning. Though it satisfies the requirement of quick response to users’ commands and environmental changes, learning real-time search (LRTS suffers from the heuristic depressions where agents behave irrationally. There have introduced several effective solutions, such as state abstractions. This paper combines LRTS and encoded quad-tree abstraction which represent the search space in multiresolutions. When exploring the environments, agents are enabled to locally repair the quad-tree models and incrementally refine the spatial cognition. By virtue of the idea of state aggregation and heuristic generalization, our EQ LRTS (encoded quad-tree based LRTS possesses the ability of quickly escaping from heuristic depressions with less state revisitations. Experiments and analysis show that (a our encoding principle for quad-trees is a much more memory-efficient method than other data structures expressing quad-trees, (b EQ LRTS differs a lot in several characteristics from classical PR LRTS which represent the space and refine the paths hierarchically, and (c EQ LRTS substantially reduces the planning amount and curtails heuristic updates compared with LRTS on uniform cells.

  17. 75 FR 75706 - Dresden Nuclear Power Station, Units 2 and 3 and Quad Cities Nuclear Power Station, Unit Nos. 1...

    Science.gov (United States)

    2010-12-06

    ...- 2010-0373] Dresden Nuclear Power Station, Units 2 and 3 and Quad Cities Nuclear Power Station, Unit Nos... and DPR-25 for Dresden Nuclear Power Station, Units 2 and 3, respectively, located in Grundy County, Illinois, and to Renewed Facility Operating License Nos. DPR-29 and DPR-30 for Quad Cities Nuclear Power...

  18. QuadBase2: web server for multiplexed guanine quadruplex mining and visualization.

    Science.gov (United States)

    Dhapola, Parashar; Chowdhury, Shantanu

    2016-07-08

    DNA guanine quadruplexes or G4s are non-canonical DNA secondary structures which affect genomic processes like replication, transcription and recombination. G4s are computationally identified by specific nucleotide motifs which are also called putative G4 (PG4) motifs. Despite the general relevance of these structures, there is currently no tool available that can allow batch queries and genome-wide analysis of these motifs in a user-friendly interface. QuadBase2 (quadbase.igib.res.in) presents a completely reinvented web server version of previously published QuadBase database. QuadBase2 enables users to mine PG4 motifs in up to 178 eukaryotes through the EuQuad module. This module interfaces with Ensembl Compara database, to allow users mine PG4 motifs in the orthologues of genes of interest across eukaryotes. PG4 motifs can be mined across genes and their promoter sequences in 1719 prokaryotes through ProQuad module. This module includes a feature that allows genome-wide mining of PG4 motifs and their visualization as circular histograms. TetraplexFinder, the module for mining PG4 motifs in user-provided sequences is now capable of handling up to 20 MB of data. QuadBase2 is a comprehensive PG4 motif mining tool that further expands the configurations and algorithms for mining PG4 motifs in a user-friendly way. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. 100 Gbps IM/DD links using quad-polarization: Performance, complexity, and power dissipation

    DEFF Research Database (Denmark)

    Saldaña Cercos, Silvia; Piels, Molly; Estaran Tolosa, Jose Manuel

    2015-01-01

    A computational complexity, power consumption, and receiver sensitivity analysis for three different scenarios for short-range direct detection links is presented: 1) quad-polarization, 2) wavelength division multiplexing (WDM), and 3) parallel optics. Results show that the power consumption...... penalty associated to the quad-polarization digital signal processing (DSP) is negligibly small. However, the required analog to digital converters account for 47.6% of the total system power consumption. Transmission of 4x32 Gbps over 2 km standard single mode fiber is achieved with a receiver...

  20. Outdoor altitude stabilization of QuadRotor based on type-2 fuzzy and fuzzy PID

    Science.gov (United States)

    Wicaksono, H.; Yusuf, Y. G.; Kristanto, C.; Haryanto, L.

    2017-11-01

    This paper presents a design of altitude stabilization of QuadRotor based on type-2 fuzzy and fuzzy PID. This practical design is implemented outdoor. Barometric and sonar sensor were used in this experiment as an input for the controller YoHe. The throttle signal as a control input was provided by the controller to leveling QuadRotor in particular altitude and known well as altitude stabilization. The parameter of type-2 fuzzy and fuzzy PID was tuned in several heights to get the best control parameter for any height. Type-2 fuzzy produced better result than fuzzy PID but had a slow response in the beginning.

  1. Measurement of the CKM angle $\\gamma$ from a combination of $B^{\\pm} \\to Dh^{\\pm}$ analyses

    CERN Document Server

    INSPIRE-00258707; Abellan Beteta, C; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amerio, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bauer, Th; Bay, A; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M -O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Burducea, I; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Couturier, B; Cowan, G A; Craik, D C; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; Davis, A; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dijkstra, H; Dogaru, M; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicheur, A; Hicks, E; Hill, D; Hoballah, M; Hombach, C; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lohn, S; Longstaff, I; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Lucchesi, D; Luisier, J; Luo, H; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Maurice, E; Mazurov, A; Mc Skelly, B; McCarthy, J; McNab, A; McNulty, R; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Morello, M J; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Oyanguren, A; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petridis, K; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polycarpo, E; Popov, A; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pritchard, A; Prouve, C; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rama, M; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Rives Molina, V; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodriguez Perez, P; Roiser, S; Romanovsky, V; Romero Vidal, A; Rouvinet, J; Ruf, T; Ruffini, F; Ruiz, H; Ruiz Valls, P; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salustino Guimaraes, V; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; Smith, N A; Smith, E; Smith, M; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Sun, L; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urner, D; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiechczynski, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L; Zvyagin, A

    2013-01-01

    A combination of three LHCb measurements of the CKM angle $\\gamma$ is presented. The decays $B^\\pm\\to DK^\\pm$ and $B^\\pm\\to D\\pi^\\pm$ are used, where $D$ denotes an admixture of $D^0$ and $\\overline{D^0}$ mesons, decaying into $K^+K^-$, $\\pi^+\\pi^-$, $K^\\pm \\pi^\\mp$, $K^\\pm \\pi^\\mp \\pi^\\pm \\pi^\\mp$, $K_S\\pi^+\\pi^-$, or $K_S K^+K^-$ final states. All measurements use a dataset corresponding to 1.0 fb$^{-1}$ of data. Combining results from $B^\\pm\\to DK^\\pm$ decays alone a best-fit value of $\\gamma = 72.0^\\circ$ is found, and confidence intervals are set \\begin{align*} \\gamma \\in [56.4,86.7]^\\circ \\quad &{\\rm at\\ 68\\%\\,CL}\\,,\\\\ \\gamma \\in [42.6,99.6]^\\circ \\quad &{\\rm at\\ 95\\%\\,CL}\\,. \\end{align*} The best-fit value of $\\gamma$ found from a combination of results from $B^\\pm\\to D\\pi^\\pm$ decays alone, is $\\gamma = 18.9^\\circ$, and the confidence intervals \\begin{align*} \\gamma \\in [7.4,99.2]^\\circ \\quad \\cup \\quad [167.9,176.4]^\\circ \\quad &{\\rm at\\ 68\\%\\,CL}\\, \\end{align*} are set, without constrai...

  2. Toward a High-Efficient Utilization of Solar Radiation by Quad-Band Solar Spectral Splitting

    OpenAIRE

    Cao, Feng; Tang, Lu; Sun, Tianyi; Ren, Zhifeng; Huang, Yi; Boriskina, Svetlana V; Chen, Gang

    2016-01-01

    The promising quad-band solar spectral splitter incorporates the properties of the optical filter and the spectrally selective solar thermal absorber can direct PV band to PV modules and absorb thermal band energy for thermal process with low thermal losses. It provides a new strategy for spectral splitting and offers potential ways for hybrid PVT system design.

  3. 7-year retrospective review of quad bike injuries admitted to Starship Children's Hospital.

    Science.gov (United States)

    Pearce, Rebecca; Miles, Fiona

    2015-05-15

    To ascertain morbidity and mortality of children who presented to Starship Children's Hospital with injuries from a quad bike incident from 2007 to 2014, and to review whether current guidelines are sufficient to prevent injury. A retrospective case note review of all children under the age of 16 years who presented to Starship Hospital with an injury sustained whilst riding a quad bike between January 2007 and July 2014. Twenty-seven patients were identified through both the Starship Children's Hospital Trauma and Paediatric Intensive Care databases with injuries resulting from a quad bike incident. Fifteen patients (56%) had multisystem injuries. The average injury severity score (ISS) was 14 (range 1-75). ISS was higher in those of younger age (injuries with no helmet. Seven (25.9%) patients required PICU admission, two patients died (7.4%) and three patients (12%) survived to discharge with disability. This study supports current published guidelines which recommend limiting the use of quad bikes by children. Current guidelines do not, however, prevent injury in the paediatric population.

  4. 76 FR 19746 - Expansion of Foreign-Trade Zone 133; Quad-Cities, IL/IA

    Science.gov (United States)

    2011-04-08

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1749] Expansion of Foreign-Trade Zone 133; Quad-Cities, IL/IA Pursuant to its authority under the Foreign-Trade Zones Act of June 18, 1934, as amended (19 U.S.C. 81a-81u), the Foreign-Trade Zones Board (the Board) adopts the following Order...

  5. The quad pill, a once-daily combination therapy for HIV infection.

    Science.gov (United States)

    Johnson, Leonard B; Saravolatz, Louis D

    2014-01-01

    The quad pill is the newest single-pill, once-daily option for the treatment of human immunodeficiency virus (HIV) type 1 infection. In addition to tenofovir difumarate (TDF) and emtricitabine (FTC), the quad pill includes cobicistat (COBI; an inactivator of cytochrome P450 isoenzyme CYP3A without anti-HIV activity) and a new integrase inhibitor, elvitegravir (EVG). The quad does not have drug interactions with H2-receptor antagonists or proton pump inhibitors, does not cause central nervous system (CNS) side effects, and is pregnancy category B. It does have substantial drug interactions with medications that are metabolized using CYP3A and causes reversible declines in estimated glomerular filtration rate (eGFR) owing to inhibition of renal tubule transport of creatinine. In clinical trials, the virologic and immunologic efficacy of the quad pill is equivalent to that of other comparator regimens with low rates of discontinuation. The major side effect is nauseam which is self-limited, and the primary mutations associated with treatment failure frequently lead to cross-resistance with raltegravir (RAL).

  6. "Sleep out on the Quad": An Opportunity for Experiential Education and Servant Based Leadership

    Science.gov (United States)

    Johnson, Kristen A.; Grazulis, Jessica; White, Joshua K.

    2014-01-01

    One of the purposes of higher education is to promote citizenship and social justice. This article explores the way Aurora University is helping students to discover what matters through the impact of "Sleep Out on the Quad," which is an event that uses multiple pedagogies to impact student learning of homelessness. It serves as a call…

  7. Precise orbit determination for quad-constellation satellites at Wuhan University: strategy, result validation, and comparison

    Science.gov (United States)

    Guo, Jing; Xu, Xiaolong; Zhao, Qile; Liu, Jingnan

    2016-02-01

    This contribution summarizes the strategy used by Wuhan University (WHU) to determine precise orbit and clock products for Multi-GNSS Experiment (MGEX) of the International GNSS Service (IGS). In particular, the satellite attitude, phase center corrections, solar radiation pressure model developed and used for BDS satellites are addressed. In addition, this contribution analyzes the orbit and clock quality of the quad-constellation products from MGEX Analysis Centers (ACs) for a common time period of 1 year (2014). With IGS final GPS and GLONASS products as the reference, Multi-GNSS products of WHU (indicated by WUM) show the best agreement among these products from all MGEX ACs in both accuracy and stability. 3D Day Boundary Discontinuities (DBDs) range from 8 to 27 cm for Galileo-IOV satellites among all ACs' products, whereas WUM ones are the largest (about 26.2 cm). Among three types of BDS satellites, MEOs show the smallest DBDs from 10 to 27 cm, whereas the DBDs for all ACs products are at decimeter to meter level for GEOs and one to three decimeter for IGSOs, respectively. As to the satellite laser ranging (SLR) validation for Galileo-IOV satellites, the accuracy evaluated by SLR residuals is at the one decimeter level with the well-known systematic bias of about -5 cm for all ACs. For BDS satellites, the accuracy could reach decimeter level, one decimeter level, and centimeter level for GEOs, IGSOs, and MEOs, respectively. However, there is a noticeable bias in GEO SLR residuals. In addition, systematic errors dependent on orbit angle related to mismodeled solar radiation pressure (SRP) are present for BDS GEOs and IGSOs. The results of Multi-GNSS combined kinematic PPP demonstrate that the best accuracy of position and fastest convergence speed have been achieved using WUM products, particularly in the Up direction. Furthermore, the accuracy of static BDS only PPP degrades when the BDS IGSO and MEO satellites switches to orbit-normal orientation

  8. 75 FR 70691 - World Color Mt. Morris, IL LLC, Premedia Chicago Division, Currently Known as Quad/Graphics, Inc...

    Science.gov (United States)

    2010-11-18

    ... had their wages reported under a separate unemployment insurance (UI) tax account under the name Quad... to India and China. The amended notice applicable to TA-W-74,142 is hereby issued as follows: All...

  9. 1:12,000 Grid of Louisiana, Geographic NAD83, LGS (2007) [quad12k_losco_2007

    Data.gov (United States)

    Louisiana Geographic Information Center — This "QUAD12K_LOSCO_2007" ploygon shapefile is a reference index to the polygon footprints of Digital Orthographic Quarter Quadrangles (DOQQs) for Louisiana and a...

  10. 1:24,000 Grid of Louisiana, Geographic NAD83, LGS (2007) [quad6k_losco_2007

    Data.gov (United States)

    Louisiana Geographic Information Center — This "QUAD24K_LOSCO_2007" ploygon shapefile is a reference index to the polygon footprints of 1:24,000 scale quadrangles for Louisiana and a selected surrounding...

  11. 1:6,000 Grid of Louisiana, Geographic NAD83, LGS (2007) [quad6k_losco_2007

    Data.gov (United States)

    Louisiana Geographic Information Center — This "QUAD6K_LOSCO_2007" ploygon shapefile is a reference index to the polygon footprints of quarters of the Digital Orthographic Quarter Quadrangles (DOQQs), or...

  12. Feasibility study on proposed Amtrak service from Chicago, to Iowa City, Iowa via Quad Cities : executive summary.

    Science.gov (United States)

    2008-04-18

    Soon after the Illinois Department of Transportation (Ill. DOT) requested Amtrak to : conduct a feasibility study on proposed Amtrak service between Chicago and the : Illinois Quad Cities, the Iowa Department of Transportation (Iowa DOT) ...

  13. Actuator Fault Estimation and Reconfiguration Control for the Quad-Rotor Helicopter

    Directory of Open Access Journals (Sweden)

    Fuyang Chen

    2016-02-01

    Full Text Available In this paper, an improved reconfiguration control scheme via an H∞ fault observer and adaptive control is studied for the quad-rotor helicopter with actuator faults. The bilinear problem is eliminated by constructing fault compensation and control law reconfiguration in the adaptive controller. Fault estimation is achieved by designing the fault observer with an H∞ performance index, which is applied to evaluate the ‘locking in place’ fault of the actuator in a quad-rotor helicopter. By drawing the H∞ performance index into the adaptive fault observer, an asymptotically convergent estimated error can be attained and the burden of the adaptive controller is alleviated. Some simulation and experimental results confirm the availability of the reconfiguration control scheme.

  14. A Compact Quad-Band Bandpass Filter Based on Defected Microstrip Structure

    Science.gov (United States)

    Chen, Lei; Li, Xiao Yan; Wei, Feng

    2017-07-01

    A compact quad-band band-pass filter (BPF) based on stub loaded resonators (SLRs) with defected microstrip structure (DMS) is analyzed and designed in this paper. The proposed resonator is created by embedding DMS into the SLR and can achieve four narrow passbands. By employing the pseudointerdigital coupling structure between the two resonators, transmission zeros among each passband are generated to improve the passband selectivity and a high isolation is achieved. In order to validate its practicability, a prototype of a quad-band BPF centred at 1.57, 2.5, 4.3 and 5.2 GHz is designed and fabricated. The proposed filter is more compact due to the slow-wave characteristic of DMS. The simulated and measured results are in good agreement with each other. In addition, the DMS idea can be extended to the design of other microstrip passive devices.

  15. Mechanical evaluation of quad-helix appliance made of low-nickel stainless steel wire.

    Science.gov (United States)

    dos Santos, Rogério Lacerda; Pithon, Matheus Melo

    2013-01-01

    The objective of this study was to test the hypothesis that there is no difference between stainless steel and low-nickel stainless steel wires as regards mechanical behavior. Force, resilience, and elastic modulus produced by Quad-helix appliances made of 0.032-inch and 0.036-inch wires were evaluated. Sixty Quad-helix appliances were made, thirty for each type of alloy, being fifteen for each wire thickness, 0.032-in and 0.036-in. All the archwires were submitted to mechanical compression test using an EMIC DL-10000 machine simulating activations of 4, 6, 9, and 12 mm. Analysis of variance (ANOVA) with multiple comparisons and Tukey's test were used (p steel alloy had force, resilience, and elastic modulus similar to those made of stainless steel alloy.

  16. QUAD fever: beware of non-infectious fever in high spinal cord injuries.

    Science.gov (United States)

    Goyal, Jyoti; Jha, Rakesh; Bhatia, Paramjeet; Mani, Raj Kumar

    2017-06-18

    A case of cervical spinal cord injury and quadriparesis with prolonged fever is being described. Initially, the patient received treatment for well-documented catheter-related bloodstream infection. High spiking fever returned and persisted with no obvious evidence of infection. The usual non-infectious causes too were carefully excluded. QUAD fever or fever due to spinal cord injury itself was considered. The pathogenetic basis of QUAD fever is unclear but could be attributed to autonomic dysfunction and temperature dysregulation. Awareness of this little known condition could help in avoiding unnecessary antimicrobial therapy and in more accurate prognostication. Unlike several previous reported cases that ended fatally, the present case ran a relatively benign course. The spectrum of presentations may therefore be broader than hitherto appreciated. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  17. Stabilization and control of quad-rotor helicopter using a smartphone device

    Science.gov (United States)

    Desai, Alok; Lee, Dah-Jye; Moore, Jason; Chang, Yung-Ping

    2013-01-01

    In recent years, autonomous, micro-unmanned aerial vehicles (micro-UAVs), or more specifically hovering micro- UAVs, have proven suitable for many promising applications such as unknown environment exploration and search and rescue operations. The early versions of UAVs had no on-board control capabilities, and were difficult for manual control from a ground station. Many UAVs now are equipped with on-board control systems that reduce the amount of control required from the ground-station operator. However, the limitations on payload, power consumption and control without human interference remain the biggest challenges. This paper proposes to use a smartphone as the sole computational device to stabilize and control a quad-rotor. The goal is to use the readily available sensors in a smartphone such as the GPS, the accelerometer, the rate-gyros, and the camera to support vision-related tasks such as flight stabilization, estimation of the height above ground, target tracking, obstacle detection, and surveillance. We use a quad-rotor platform that has been built in the Robotic Vision Lab at Brigham Young University for our development and experiments. An Android smartphone is connected through the USB port to an external hardware that has a microprocessor and circuitries to generate pulse-width modulation signals to control the brushless servomotors on the quad-rotor. The high-resolution camera on the smartphone is used to detect and track features to maintain a desired altitude level. The vision algorithms implemented include template matching, Harris feature detector, RANSAC similarity-constrained homography, and color segmentation. Other sensors are used to control yaw, pitch, and roll of the quad-rotor. This smartphone-based system is able to stabilize and control micro-UAVs and is ideal for micro-UAVs that have size, weight, and power limitations.

  18. Adaptive Neural Network Sliding Mode Control for Quad Tilt Rotor Aircraft

    OpenAIRE

    Yanchao Yin; Hongwei Niu; Xiaobao Liu

    2017-01-01

    A novel neural network sliding mode control based on multicommunity bidirectional drive collaborative search algorithm (M-CBDCS) is proposed to design a flight controller for performing the attitude tracking control of a quad tilt rotors aircraft (QTRA). Firstly, the attitude dynamic model of the QTRA concerning propeller tension, channel arm, and moment of inertia is formulated, and the equivalent sliding mode control law is stated. Secondly, an adaptive control algorithm is presented to eli...

  19. An Approach to Quad Meshing Based On Cross Valued Maps and the Ginzburg-Landau Theory

    Energy Technology Data Exchange (ETDEWEB)

    Viertel, Ryan [Univ. of Utah, Salt Lake City, UT (United States). Dept. of Mathematics; Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Osting, Braxton [Univ. of Utah, Salt Lake City, UT (United States). Dept. of Mathematics

    2017-08-01

    A generalization of vector fields, referred to as N-direction fields or cross fields when N=4, has been recently introduced and studied for geometry processing, with applications in quadrilateral (quad) meshing, texture mapping, and parameterization. We make the observation that cross field design for two-dimensional quad meshing is related to the well-known Ginzburg-Landau problem from mathematical physics. This identification yields a variety of theoretical tools for efficiently computing boundary-aligned quad meshes, with provable guarantees on the resulting mesh, for example, the number of mesh defects and bounds on the defect locations. The procedure for generating the quad mesh is to (i) find a complex-valued "representation" field that minimizes the Dirichlet energy subject to a boundary constraint, (ii) convert the representation field into a boundary-aligned, smooth cross field, (iii) use separatrices of the cross field to partition the domain into four sided regions, and (iv) mesh each of these four-sided regions using standard techniques. Under certain assumptions on the geometry of the domain, we prove that this procedure can be used to produce a cross field whose separatrices partition the domain into four sided regions. To solve the energy minimization problem for the representation field, we use an extension of the Merriman-Bence-Osher (MBO) threshold dynamics method, originally conceived as an algorithm to simulate motion by mean curvature, to minimize the Ginzburg-Landau energy for the optimal representation field. Lastly, we demonstrate the method on a variety of test domains.

  20. MCP detector read out with a bare quad Timepix at kilohertz frame rates

    International Nuclear Information System (INIS)

    Vallerga, J; Tremsin, A; McPhate, J; Siegmund, O; Raffanti, R

    2011-01-01

    The existing Berkeley neutron sensitive MCP/Timepix hybrid detector has been very successful at demonstrating energy resolved spatial imaging with a single Timepix ASIC read out at a ∼ 30 Hz frame rate where each neutron's position and time (energy) is determined (X,Y,E). By increasing the detector format using a quad arrangement of Timepix readouts and increasing the frame rate to 1 kHz, we can increase our total event throughput by a factor of 120, thereby taking full advantage of the high fluxes of modern pulsed neutron sources (10 6 n cm -2 s -1 ). The key to this conversion is a new design for the ASIC readout, called the Berkeley Quad Timepix detector, consisting of 3 major subsystems. The first is a quad (2 x 2) bare Timepix ASIC board mounted directly behind the neutron sensitive MCPs in a hermetic vacuum enclosure with a sapphire window. The data from the Timepix ASICs flow to the second subsystem called the Interface board whose field programmable gate array (FPGA) rearranges and converts the digital bit stream to LVDS logic levels before sending downstream to the third subsystem, the Roach board. The Roach board is also FPGA based, and takes the data from all the ASICs and analyses the frames to extract information on the input events to pass on to the host PC. This paper describes in detail the hardware and firmware designs to accomplish this task.

  1. The Vacuum-Compacted Regolith Gripping Mechanism and Unmanned Flights via Quad-Rotors

    Science.gov (United States)

    Scott, Rollin L.

    2014-01-01

    During the course of the Kennedy Space Center Summer Internship, two main experiments were performed: The Vacuum-Compacted Regolith Gripping Mechanism and Unmanned Flights via Quad-copters. The objectives of the Vacuum-Compacted Regolith Gripping Mechanism, often abbreviated as the Granular Gripper, are to exhibit Space Technology, such as a soft robotic hand, lift different apparatuses used to excavate regolith, and conserve energy while executing its intended task. The project is being conducted to test how much weight the Granular Gripper can hold. With the use of an Animatronic Robotic Hand, Arduino Uno, and other components, the system was calibrated before actually conducting the intended weight test. The maximum weight each finger could hold with the servos running, in the order of pinky, ring, middle, and index fingers, are as follows: 1.340N, 1.456 N, 0.9579 N, and 1.358 N. Using the small vacuum pump system, the maximum weight each finger could hold, in the same order, was: 4.076 N, 6.159 N, 5.454 N, and 4.052 N. The maximum torques on each of the fingers when the servos were running, in the same respective order, was: 0.0777 Nm, 0.0533 Nm, 0.0648 Nm, and 0.0532 Nm. The maximum torques on the individual fingers, when the small vacuum pump was in effect, in the same order as above, was: 0.2318 Nm, 0.3032 Nm, 0.2741 Nm, and 0.1618 Nm. In testing all the fingers with the servos running, the total weight was 5.112 N and the maximum torque on the all the fingers was 0.2515 Nm. However, when the small vacuum pump system was used, the total weight was 19.741 N and the maximum torque on the all the fingers was 0.9713 Nm. The conclusion that was drawn stated that using the small vacuum pump system proved nearly 4 times more effective when testing how much weigh the hand could hold. The resistance provided by the compacted sand in the glove allowed more weight to be held by the hand and glove. Also, when the servos turned off and the hand still retaining its

  2. Development of an Effective System Identification and Control Capability for Quad-copter UAVs

    Science.gov (United States)

    Wei, Wei

    In recent years, with the promise of extensive commercial applications, the popularity of Unmanned Aerial Vehicles (UAVs) has dramatically increased as witnessed by publications and mushrooming research and educational programs. Over the years, multi-copter aircraft have been chosen as a viable configuration for small-scale VTOL UAVs in the form of quad-copters, hexa-copters and octo-copters. Compared to the single main rotor configuration such as the conventional helicopter, multi-copter airframes require a simpler feedback control system and fewer mechanical parts. These characteristics make these UAV platforms, such as quad-copter which is the main emphasis in this dissertation, a rugged and competitive candidate for many applications in both military and civil areas. Because of its configuration and relative size, the small-scale quad-copter UAV system is inherently very unstable. In order to develop an effective control system through simulation techniques, obtaining an accurate dynamic model of a given quad-copter is imperative. Moreover, given the anticipated stringent safety requirements, fault tolerance will be a crucial component of UAV certification. Accurate dynamic modeling and control of this class of UAV is an enabling technology and is imperative for future commercial applications. In this work, the dynamic model of a quad-copter system in hover flight was identified using frequency-domain system identification techniques. A new and unique experimental system, data acquisition and processing procedure was developed catering specifically to the class of electric powered multi-copter UAV systems. The Comprehensive Identification from FrEquency Responses (CIFER RTM) software package, developed by US Army Aviation Development Directorate -- AFDD, was utilized along with flight tests to develop dynamic models of the quad-copter system. A new set of flight tests were conducted and the predictive capability of the dynamic models were successfully validated

  3. Exposure Effects on the Productivity of Commercial Bombus impatiens (Hymenoptera: Apidae) Quads During Bloom in Watermelon Fields.

    Science.gov (United States)

    Marchese, J I; Johnson, G J; Delaney, D A

    2015-08-01

    In light of population declines of honey bees (Apis mellifera L.), research has refocused attention on alternative pollinators and their potential to fulfill pollination services within economically important agricultural crops. Bumble bees are one such alternative, and within the past 20 yr, these pollinators have been reared and sold as commercial pollinators. Investigation into their use has been limited and more research is needed to improve pollinator effectiveness in field settings. Quad pollination units of the commercially reared native bumble bee species, the common eastern bumble bee (Bombus impatiens Cresson), were monitored and evaluated for productivity during peak watermelon [Citrullus lanatus (Thunberg) Matsumura & Nakai] bloom in southern Delaware. Differing colony exposures including various shade structure designs and natural shade were compared to assess the quality of the shade in regards to bumble bee activity during watermelon bloom. Quads receiving different nest treatments were evaluated on the basis of foraging activity and colony weight gain. Results indicated that colonies within quads provided with artificial or natural shade had significantly more foraging activity, weighed more, and produced more cells than colonies in quads placed in the field with no shade. Colonies within quads provided with artificial and natural shade peaked later in terms of foraging and weight gain, suggesting that growers could extend harvest to take advantage of later markets and possible movement into fields that were planted later. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. QuadCam - A Quadruple Polarimetric Camera for Space Situational Awareness

    Science.gov (United States)

    Skuljan, J.

    A specialised quadruple polarimetric camera for space situational awareness, QuadCam, has been built at the Defence Technology Agency (DTA), New Zealand, as part of collaboration with the Defence Science and Technology Laboratory (Dstl), United Kingdom. The design was based on a similar system originally developed at Dstl, with some significant modifications for improved performance. The system is made up of four identical CCD cameras looking in the same direction, but in a different plane of polarisation at 0, 45, 90 and 135 degrees with respect to the reference plane. A standard set of Stokes parameters can be derived from the four images in order to describe the state of polarisation of an object captured in the field of view. The modified design of the DTA QuadCam makes use of four small Raspberry Pi computers, so that each camera is controlled by its own computer in order to speed up the readout process and ensure that the four individual frames are taken simultaneously (to within 100-200 microseconds). In addition, a new firmware was requested from the camera manufacturer so that an output signal is generated to indicate the state of the camera shutter. A specialised GPS unit (also developed at DTA) is then used to monitor the shutter signals from the four cameras and record the actual time of exposure to an accuracy of about 100 microseconds. This makes the system well suited for the observation of fast-moving objects in the low Earth orbit (LEO). The QuadCam is currently mounted on a Paramount MEII robotic telescope mount at the newly built DTA space situational awareness observatory located on Whangaparaoa Peninsula near Auckland, New Zealand. The system will be used for tracking satellites in low Earth orbit and geostationary belt as well. The performance of the camera has been evaluated and a series of test images have been collected in order to derive the polarimetric signatures for selected satellites.

  5. Reversibility of the Quad-Edge operations in the Voronoi data structure

    DEFF Research Database (Denmark)

    Mioc, Darka; Anton, François; Gold, Christopher

    2007-01-01

    In Geographic Information Systems the reversibility of map update operations have not been explored yet. In this paper we are using the Voronoi based Quad-edge data structure to define reversible map update operations. The reversibility of the map operations have been formalised at the lowest level......, as the basic algorithms for addition, dele- tion and moving of spatial objects. Having developed re- versible map operations on the lowest level, we were able to maintain reversibility of the map updates at higher level as well. The reversibility in GIS can be used for efficient implementation of rollback...

  6. Modified quad helix appliance for thumb sucking and cross bite correction

    Directory of Open Access Journals (Sweden)

    C Vinay

    2013-01-01

    Full Text Available Digit sucking habit is a learned pattern of behavior commonly seen in children of preschool age. Prolonged digit sucking beyond the preschool age, lead to the development of malocclusion such as anterior open bite, maxillary constriction and posterior crossbite. Treatment strategies include interception of habit and correction of the malocclusion. The present case report describes a modified quad helix appliance used successfully in a 9-year-old child to intercept thumb sucking habit and simultaneous correction of posterior crossbite. The appliance has the advantage of easy fabrication, being versatile and more patients compliant.

  7. Process characteristics and design methods for a 300 deg quad OP amp

    Science.gov (United States)

    Beasom, J. D.; Patterson, R. B., III

    1981-01-01

    The results of process characterization, circuit design, and reliability studies for the development of a quad OP amplifier intended for use up to 300 C are presented. A dielectrically isolated complementary vertical bipolar process was chosen to fabricate the amplifier in order to eliminate isolation leakage and the possibility of latch up. Characterization of NPN and PNP junctions showed them to be suitable for use up to 300 C. Interconnect reliability was predicted to be greater than four years mean time between failure. Parasitic MOS formation was eliminated by isolation of each device.

  8. Modified Quad Helix for Correction of Severely Rotated Incisors in Cleft Cases

    Directory of Open Access Journals (Sweden)

    Aneesha Ashok Shetty

    2014-01-01

    Full Text Available Clefts of the lip, alveolus and/or palate are often associated with several dental anomalies, the most common of which are severely rotated maxillary incisors. Patients with such congenital deformities seek orthodontic treatment as early as possible, for an esthetic as well as psychosocial benefit. Here, a new clinical technique is demonstrated for correction of a severely rotated maxillary central incisor which can be carried out in the mixed dentition phase itself, by modifying a commonly used palatal expansion appliance: the quad helix.

  9. Experimental investigation of a quad-rotor biplane micro air vehicle

    Science.gov (United States)

    Bogdanowicz, Christopher Michael

    Micro air vehicles are expected to perform demanding missions requiring efficient operation in both hover and forward flight. This thesis discusses the development of a hybrid air vehicle which seamlessly combines both flight capabilities: hover and high-speed forward flight. It is the quad-rotor biplane, which weighs 240 grams and consists of four propellers with wings arranged in a biplane configuration. The performance of the vehicle system was investigated in conditions representative of flight through a series of wind tunnel experiments. These studies provided an understanding of propeller-wing interaction effects and system trim analysis. This showed that the maximum speed of 11 m/s and a cruise speed of 4 m/s were achievable and that the cruise power is approximately one-third of the hover power. Free flight testing of the vehicle successfully highlighted its ability to achieve equilibrium transition flight. Key design parameters were experimentally investigated to understand their effect on overall performance. It was found that a trade-off between efficiency and compactness affects the final choice of the design. Design improvements have allowed for decreases in vehicle weight and ground footprint, while increasing structural soundness. Numerous vehicle designs, models, and flight tests have proven system scalability as well as versatility, including an upscaled model to be utilized in an extensive commercial package delivery system. Overall, the quad-rotor biplane is proven to be an efficient and effective multi-role vehicle.

  10. Gated listmode acquisition with the QuadHIDAC animal PET to image mouse hearts

    International Nuclear Information System (INIS)

    Schaefers, K.P.; Lang, N.; Stegger, L.; Schober, O.; Schaefers, M.

    2006-01-01

    Purpose: the aim of this study was to develop ECG and respiratory gating in combination with listmode acquisition for the quadHIDAC small-animal PET scanner. Methods: ECG and respiratory gating was realized with the help of an external trigger device (BioVET) synchronized with the listmode acquisition. Listmode data of a mouse acquisition (injected with 6.5 MBq of 18 F-FDG) were sorted according to three different gating definitions: 12 cardiac gates, 8 respiratory gates and a combination of 8 cardiac and 8 respiratory gates. Images were reconstructed with filtered back-projection (ramp filter), and parameters like left ventricular wall thickness (WT), wall-to-wall separation (WS) and blood to myocardium activity ratios (BMR) were calculated. Results: cardiac gated images show improvement of all parameters (WT 2.6 mm, WS 4.1 mm, BRM 2.3) in diastole compared to ungated images (WT 3.0 mm, WS 3.4 mm, BMR 1.3). Respiratory gating had little effect on calculated parameters. Conclusion: ECG gating with the quadHIDAC can improve myocardial image quality in mice. This could have a major impact on the calculation of an image-derived input function for kinetic modelling. (orig.)

  11. Quad shot - hypofractionated radiotherapy for palliation in advanced squamous cell carcinoma of head and neck

    International Nuclear Information System (INIS)

    Maqsood, T.; Ali, U.; Arif, S.

    2017-01-01

    The objective of this study was to determine the efficacy of quad-shot radiation therapy for palliation in locally advanced and metastatic inoperable squamous cell carcinomas of head and neck. Study Design: A quasi-experimental study. Place and Duration of Study: Oncology department, Combined Military Hospital Rawalpindi, from Sep 2012 to Sep 2013. Material and Methods: Thirty five patients were included with histologically confirmed advanced inoperable squamous cell carcinoma in head and neck region, performance status 2 or 3 and survival =3 months. Patients were treated with radiation therapy 14 Gy in four fractions, megavoltage beam, twice daily fractions (at least 6 hours apart), for 2 consecutive days. Symptoms due to cancer (pain and dysphagia) were assessed as per common toxicity criteria adverse event version 4.0 on day 0 before treatment and day 21 after start of treatment. Results: Grades of pain and dysphagia showed significant improvement after treatment with a p-value <0.001. A total of 91.4% patients showed an improvement in grade of pain (32 out of 35 patients) and 45.7% of patients showed improvement in grade of dysphagia (16 out of 35 patients). There was a statistically significant decrease in grades of pain and dysphagia after treatment. Conclusion: The short duration of hypofractionated radiotherapy with Quad Shot was effective with respect to symptom palliation in locally advanced and metastatic inoperable head and neck cancers.

  12. Mechanical evaluation of quad-helix appliance made of low-nickel stainless steel wire

    Directory of Open Access Journals (Sweden)

    Rogério Lacerda dos Santos

    2013-06-01

    Full Text Available OBJECTIVE: The objective of this study was to test the hypothesis that there is no difference between stainless steel and low-nickel stainless steel wires as regards mechanical behavior. Force, resilience, and elastic modulus produced by Quad-helix appliances made of 0.032-inch and 0.036-inch wires were evaluated. METHODS: Sixty Quad-helix appliances were made, thirty for each type of alloy, being fifteen for each wire thickness, 0.032-in and 0.036-in. All the archwires were submitted to mechanical compression test using an EMIC DL-10000 machine simulating activations of 4, 6, 9, and 12 mm. Analysis of variance (ANOVA with multiple comparisons and Tukey's test were used (p < 0.05 to assess force, resilience, and elastic modulus. RESULTS: Statistically significant difference in the forces generated, resilience and elastic modulus were found between the 0.032-in 0.036-in thicknesses (p < 0.05. CONCLUSIONS: Appliances made of low-nickel stainless steel alloy had force, resilience, and elastic modulus similar to those made of stainless steel alloy.

  13. Quad Index

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  14. A Micro-Force Sensor with Slotted-Quad-Beam Structure for Measuring the Friction in MEMS Bearings

    Science.gov (United States)

    Liu, Huan; Yang, Shuming; Zhao, Yulong; Jiang, Zhuangde; Liu, Yan; Tian, Bian

    2013-01-01

    Presented here is a slotted-quad-beam structure sensor for the measurement of friction in micro bearings. Stress concentration slots are incorporated into a conventional quad-beam structure to improve the sensitivity of force measurements. The performance comparison between the quad-beam structure sensor and the slotted-quad-beam structure sensor are performed by theoretical modeling and finite element (FE) analysis. A hollow stainless steel probe is attached to the mesa of the sensor chip by a tailor-made organic glass fixture. Concerning the overload protection of the fragile beams, a glass wafer is bonded onto the bottom of sensor chip to limit the displacement of the mesa. The calibration of the packaged device is experimentally performed by a tri-dimensional positioning stage, a precision piezoelectric ceramic and an electronic analytical balance, which indicates its favorable sensitivity and overload protection. To verify the potential of the proposed sensor being applied in micro friction measurement, a measurement platform is established. The output of the sensor reflects the friction of bearing resulting from dry friction and solid lubrication. The results accord with the theoretical modeling and demonstrate that the sensor has the potential application in measuring the micro friction force under stable stage in MEMS machines. PMID:24084112

  15. The effect on cross sections for Quad Cities by introducing control rod history in the assembly program LEWARD

    International Nuclear Information System (INIS)

    Nonboel, E.

    1989-08-01

    This paper shows the effect on the 2-group neutron cross sections for the BWR reactor Quad Cities by introducing control rod ''history'' in the assembly program LEWARD. Control rod ''history'' is a concept which accounts for the movement of control rods during operation. (author)

  16. A micro-force sensor with slotted-quad-beam structure for measuring the friction in MEMS bearings.

    Science.gov (United States)

    Liu, Huan; Yang, Shuming; Zhao, Yulong; Jiang, Zhuangde; Liu, Yan; Tian, Bian

    2013-09-30

    Presented here is a slotted-quad-beam structure sensor for the measurement of friction in micro bearings. Stress concentration slots are incorporated into a conventional quad-beam structure to improve the sensitivity of force measurements. The performance comparison between the quad-beam structure sensor and the slotted-quad-beam structure sensor are performed by theoretical modeling and finite element (FE) analysis. A hollow stainless steel probe is attached to the mesa of the sensor chip by a tailor-made organic glass fixture. Concerning the overload protection of the fragile beams, a glass wafer is bonded onto the bottom of sensor chip to limit the displacement of the mesa. The calibration of the packaged device is experimentally performed by a tri-dimensional positioning stage, a precision piezoelectric ceramic and an electronic analytical balance, which indicates its favorable sensitivity and overload protection. To verify the potential of the proposed sensor being applied in micro friction measurement, a measurement platform is established. The output of the sensor reflects the friction of bearing resulting from dry friction and solid lubrication. The results accord with the theoretical modeling and demonstrate that the sensor has the potential application in measuring the micro friction force under stable stage in MEMS machines.

  17. A Micro-Force Sensor with Slotted-Quad-Beam Structure for Measuring the Friction in MEMS Bearings

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2013-09-01

    Full Text Available Presented here is a slotted-quad-beam structure sensor for the measurement of friction in micro bearings. Stress concentration slots are incorporated into a conventional quad-beam structure to improve the sensitivity of force measurements. The performance comparison between the quad-beam structure sensor and the slotted-quad-beam structure sensor are performed by theoretical modeling and finite element (FE analysis. A hollow stainless steel probe is attached to the mesa of the sensor chip by a tailor-made organic glass fixture. Concerning the overload protection of the fragile beams, a glass wafer is bonded onto the bottom of sensor chip to limit the displacement of the mesa. The calibration of the packaged device is experimentally performed by a tri-dimensional positioning stage, a precision piezoelectric ceramic and an electronic analytical balance, which indicates its favorable sensitivity and overload protection. To verify the potential of the proposed sensor being applied in micro friction measurement, a measurement platform is established. The output of the sensor reflects the friction of bearing resulting from dry friction and solid lubrication. The results accord with the theoretical modeling and demonstrate that the sensor has the potential application in measuring the micro friction force under stable stage in MEMS machines.

  18. Calculation of Quad-Cities Central Bundle Documented by the U.S. in FY98 Using Russian Computer Codes

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovichev, A.M.

    2001-06-19

    The report presents calculation results of isotopic composition of irradiated fuel performed for the Quad Cities-1 reactor bundle with UO{sub 2} and MOX fuel. The MCU-REA code was used for calculations. The code is developed in Kurchatov Institute, Russia. The MCU-REA results are compared with the experimental data and HELIOS code results.

  19. Using implicit association tests in age-heterogeneous samples: The importance of cognitive abilities and quad model processes.

    Science.gov (United States)

    Wrzus, Cornelia; Egloff, Boris; Riediger, Michaela

    2017-08-01

    Implicit association tests (IATs) are increasingly used to indirectly assess people's traits, attitudes, or other characteristics. In addition to measuring traits or attitudes, IAT scores also reflect differences in cognitive abilities because scores are based on reaction times (RTs) and errors. As cognitive abilities change with age, questions arise concerning the usage and interpretation of IATs for people of different age. To address these questions, the current study examined how cognitive abilities and cognitive processes (i.e., quad model parameters) contribute to IAT results in a large age-heterogeneous sample. Participants (N = 549; 51% female) in an age-stratified sample (range = 12-88 years) completed different IATs and 2 tasks to assess cognitive processing speed and verbal ability. From the IAT data, D2-scores were computed based on RTs, and quad process parameters (activation of associations, overcoming bias, detection, guessing) were estimated from individual error rates. Substantial IAT scores and quad processes except guessing varied with age. Quad processes AC and D predicted D2-scores of the content-specific IAT. Importantly, the effects of cognitive abilities and quad processes on IAT scores were not significantly moderated by participants' age. These findings suggest that IATs seem suitable for age-heterogeneous studies from adolescence to old age when IATs are constructed and analyzed appropriately, for example with D-scores and process parameters. We offer further insight into how D-scoring controls for method effects in IATs and what IAT scores capture in addition to implicit representations of characteristics. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Adaptive compensation control for attitude adjustment of quad-rotor unmanned aerial vehicle.

    Science.gov (United States)

    Song, Zhankui; Sun, Kaibiao

    2017-07-01

    A compensation control strategy based on adaptive back-stepping technique is presented to address the problem of attitude adjustment for a quad-rotor unmanned aerial vehicle (QR- UAV) with inertia parameter uncertainties, the limited airflow disturbance and the partial loss of rotation speed effectiveness. In the design process of control system, adaptive estimation technique is introduced into the closed loop system in order to compensate the lumped disturbance term. More specifically, the designed controller utilizes "prescribed performance bounds" method, and therefore guarantees the transient performance of tracking errors, even in the presence of the lumped disturbance. Adaptive compensation algorithms under the proposed closed loop system structure are derived in the sense of Lyapunov stability analysis such that the attitude tracking error converge to a small neighborhood of equilibrium point. Finally, the simulation results demonstrate the effectiveness of the proposed controller. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Quad delay gate generator (LBL No. 21X6691 P-2)

    International Nuclear Information System (INIS)

    McDonald, R.J.; Maier, M.R.; Landis, D.A.; Wozniak, G.J.

    1986-08-01

    A quad delay gate generator has been designed and packaged in a single-width NIM module. Both delay times and gate widths may be set continuously from 25 ns to 120 μsec. In normal operation, the gate follows the delay time unless a ''stop'' pulse cuts it short. Alternatively, the module may be operated in a bipolar mode, where the delay time is set by the input ''start'' pulse and reset by the input ''stop'' pulse. Modes and coarse time ranges are set via an octal DIP switch on the front panel. Fine adjustments of the delay and gate width are made via two twenty-turn potentiometers. Stability over a several day period was measured at ∼ 250 ps on the 120 ns full scale range. LEDs gives a visual indication of both the input rate and the dead time

  2. IR radiation characteristics and operating range research for a quad-rotor unmanned aircraft vehicle.

    Science.gov (United States)

    Gong, Mali; Guo, Rui; He, Sifeng; Wang, Wei

    2016-11-01

    The security threats caused by multi-rotor unmanned aircraft vehicles (UAVs) are serious, especially in public places. To detect and control multi-rotor UAVs, knowledge of IR characteristics is necessary. The IR characteristics of a typical commercial quad-rotor UAV are investigated in this paper through thermal imaging with an IR camera. Combining the 3D geometry and IR images of the UAV, a 3D IR characteristics model is established so that the radiant power from different views can be obtained. An estimation of operating range to detect the UAV is calculated theoretically using signal-to-noise ratio as the criterion. Field experiments are implemented with an uncooled IR camera in an environment temperature of 12°C and a uniform background. For the front view, the operating range is about 150 m, which is close to the simulation result of 170 m.

  3. Contact Angle Goniometer

    Data.gov (United States)

    Federal Laboratory Consortium — Description:The FTA32 goniometer provides video-based contact angle and surface tension measurement. Contact angles are measured by fitting a mathematical expression...

  4. Adaptive sliding mode control for finite-time stability of quad-rotor UAVs with parametric uncertainties.

    Science.gov (United States)

    Mofid, Omid; Mobayen, Saleh

    2018-01-01

    Adaptive control methods are developed for stability and tracking control of flight systems in the presence of parametric uncertainties. This paper offers a design technique of adaptive sliding mode control (ASMC) for finite-time stabilization of unmanned aerial vehicle (UAV) systems with parametric uncertainties. Applying the Lyapunov stability concept and finite-time convergence idea, the recommended control method guarantees that the states of the quad-rotor UAV are converged to the origin with a finite-time convergence rate. Furthermore, an adaptive-tuning scheme is advised to guesstimate the unknown parameters of the quad-rotor UAV at any moment. Finally, simulation results are presented to exhibit the helpfulness of the offered technique compared to the previous methods. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  5. High spectral resolution lidar based on quad mach zehnder interferometer for aerosols and wind measurements on board space missions

    Directory of Open Access Journals (Sweden)

    Mariscal Jean-François

    2018-01-01

    Full Text Available We present the measurement principle and the optical design of a Quad Mach Zehnder (QMZ interferometer as HSRL technique, allowing simultaneous measurements of particle backscattering and wind velocity. Key features of this concept is to operate with a multimodal laser and do not require any frequency stabilization. These features are relevant especially for space applications for which high technical readiness level is required.

  6. A Waterline Extraction Method from Remote Sensing Image Based on Quad-tree and Multiple Active Contour Model

    Directory of Open Access Journals (Sweden)

    YU Jintao

    2016-09-01

    Full Text Available After the characteristics of geodesic active contour model (GAC, Chan-Vese model(CV and local binary fitting model(LBF are analyzed, and the active contour model based on regions and edges is combined with image segmentation method based on quad-tree, a waterline extraction method based on quad-tree and multiple active contour model is proposed in this paper. Firstly, the method provides an initial contour according to quad-tree segmentation. Secondly, a new signed pressure force(SPF function based on global image statistics information of CV model and local image statistics information of LBF model has been defined, and then ,the edge stopping function(ESF is replaced by the proposed SPF function, which solves the problem such as evolution stopped in advance and excessive evolution. Finally, the selective binary and Gaussian filtering level set method is used to avoid reinitializing and regularization to improve the evolution efficiency. The experimental results show that this method can effectively extract the weak edges and serious concave edges, and owns some properties such as sub-pixel accuracy, high efficiency and reliability for waterline extraction.

  7. Least square based sliding mode control for a quad-rotor helicopter and energy saving by chattering reduction

    Science.gov (United States)

    Sumantri, Bambang; Uchiyama, Naoki; Sano, Shigenori

    2016-01-01

    In this paper, a new control structure for a quad-rotor helicopter that employs the least squares method is introduced. This proposed algorithm solves the overdetermined problem of the control input for the translational motion of a quad-rotor helicopter. The algorithm allows all six degrees of freedom to be considered to calculate the control input. The sliding mode controller is applied to achieve robust tracking and stabilization. A saturation function is designed around a boundary layer to reduce the chattering phenomenon that is a common problem in sliding mode control. In order to improve the tracking performance, an integral sliding surface is designed. An energy saving effect because of chattering reduction is also evaluated. First, the dynamics of the quad-rotor helicopter is derived by the Newton-Euler formulation for a rigid body. Second, a constant plus proportional reaching law is introduced to increase the reaching rate of the sliding mode controller. Global stability of the proposed control strategy is guaranteed based on the Lyapunov's stability theory. Finally, the robustness and effectiveness of the proposed control system are demonstrated experimentally under wind gusts, and are compared with a regular sliding mode controller, a proportional-differential controller, and a proportional-integral-differential controller.

  8. DESDynI Quad First Stage Processor - A Four Channel Digitizer and Digital Beam Forming Processor

    Science.gov (United States)

    Chuang, Chung-Lun; Shaffer, Scott; Smythe, Robert; Niamsuwan, Noppasin; Li, Samuel; Liao, Eric; Lim, Chester; Morfopolous, Arin; Veilleux, Louise

    2013-01-01

    The proposed Deformation, Eco-Systems, and Dynamics of Ice Radar (DESDynI-R) L-band SAR instrument employs multiple digital channels to optimize resolution while keeping a large swath on a single pass. High-speed digitization with very fine synchronization and digital beam forming are necessary in order to facilitate this new technique. The Quad First Stage Processor (qFSP) was developed to achieve both the processing performance as well as the digitizing fidelity in order to accomplish this sweeping SAR technique. The qFSP utilizes high precision and high-speed analog to digital converters (ADCs), each with a finely adjustable clock distribution network to digitize the channels at the fidelity necessary to allow for digital beam forming. The Xilinx produced FX130T Virtex 5 part handles the processing to digitally calibrate each channel as well as filter and beam form the receive signals. Demonstrating the digital processing required for digital beam forming and digital calibration is instrumental to the viability of the proposed DESDynI instrument. The qFSP development brings this implementation to Technology Readiness Level (TRL) 6. This paper will detail the design and development of the prototype qFSP as well as the preliminary results from hardware tests.

  9. Design of a Reconfigurable Pulsed Quad-Cell for Cellular-Automata-Based Conformal Computing

    Directory of Open Access Journals (Sweden)

    Mariam Hoseini

    2010-01-01

    Full Text Available This paper presents the design of a reconfigurable asynchronous computing element, called the pulsed quad-cell (PQ-cell, for constructing conformal computers. Conformal computers are systems with an exceptional ability to conform to the physical and computational needs of an application. PQ-cells, like cellular automata, are assembled into arrays, communicate with neighboring cells, and are collectively capable of general computation. They operate asynchronously to scale without the limitations of a global clock and to minimize power consumption. Cell operations are stimulated by pulses which travel on different wires to represent 0's and 1's. Cells are individually configured to perform logic, move and store information, and coordinate parallel activity. The PQ-cell design targets a 0.25 μm CMOS technology. Simulations show that a single cell consumes 15.6 pJ per operation when pulsed at 1.3 GHz. Examples of multicell structures include a 98 MHz ring oscillator and a 190 MHz pipeline.

  10. Performance analysis of different PSF shapes for the quad-HIDAC PET submillimetre resolution recovery

    Energy Technology Data Exchange (ETDEWEB)

    Ortega Maynez, Leticia, E-mail: lortega@uacj.mx [Departamento de Ingenieria Eectrica y Computacion , Universidad Autonoma de Ciudad Juarez, Avenida del Charro 450 Norte, C.P. 32310 Ciudad Juarez, Chihuahua (Mexico); Dominguez de Jesus Ochoa, Humberto; Villegas Osiris Vergara, Osslan; Gordillo, Nelly; Guadalupe Cruz Sanchez, Vianey; Gutierrez Casas, Efren David [Departamento de Ingenieria Eectrica y Computacion, Universidad Autonoma de Ciudad Juarez, Avenida del Charro 450 Norte, C.P. 32310 Ciudad Juarez, Chihuahua (Mexico)

    2011-10-01

    In pre-clinical applications, it is quite important to preserve the image resolution because it is necessary to show the details of structures of small animals. Therefore, small animal PET scanners require high spatial resolution and good sensitivity. For the quad-HIDAC PET scanner, which has virtually continuous spatial sampling; improvements in resolution, noise and contrast are obtained as a result of avoiding artifacts introduced by binning the data into sampled projections used during the reconstruction process. In order to reconstruct high-resolution images in 3D-PET, background correction and resolution recovery are included within the Maximum Likelihood list-mode Expectation Maximization reconstruction model. This paper, introduces the performance analysis of the Gaussian, Laplacian and Triangular kernels. The Full-Width Half-Maximum used for each kernel was varied from 0.8 to 1.6 mm. For each quality compartment within the phantom, transaxial middle slices from the 3D reconstructed images are shown. Results show that, according to the quantitative measures, the triangular kernel has the best performance.

  11. Adaptive Neural Network Sliding Mode Control for Quad Tilt Rotor Aircraft

    Directory of Open Access Journals (Sweden)

    Yanchao Yin

    2017-01-01

    Full Text Available A novel neural network sliding mode control based on multicommunity bidirectional drive collaborative search algorithm (M-CBDCS is proposed to design a flight controller for performing the attitude tracking control of a quad tilt rotors aircraft (QTRA. Firstly, the attitude dynamic model of the QTRA concerning propeller tension, channel arm, and moment of inertia is formulated, and the equivalent sliding mode control law is stated. Secondly, an adaptive control algorithm is presented to eliminate the approximation error, where a radial basis function (RBF neural network is used to online regulate the equivalent sliding mode control law, and the novel M-CBDCS algorithm is developed to uniformly update the unknown neural network weights and essential model parameters adaptively. The nonlinear approximation error is obtained and serves as a novel leakage term in the adaptations to guarantee the sliding surface convergence and eliminate the chattering phenomenon, which benefit the overall attitude control performance for QTRA. Finally, the appropriate comparisons among the novel adaptive neural network sliding mode control, the classical neural network sliding mode control, and the dynamic inverse PID control are examined, and comparative simulations are included to verify the efficacy of the proposed control method.

  12. Development of a highly maneuverable unmanned underwater vehicle on the basis of quad-copter dynamics

    Science.gov (United States)

    Amin, Osman Md; Karim, Md. Arshadul; Saad, Abdullah His

    2017-12-01

    At present, research on unmanned underwater vehicle (UUV) has become a significant & familiar topic for researchers from various engineering fields. UUV is of mainly two types - AUV (Autonomous Underwater vehicle) & ROV (Remotely Operated Vehicle). There exist a significant number of published research papers on UUV, where very few researchers emphasize on the ease of maneuvering and control of UUV. Maneuvering is important for underwater vehicle in avoiding obstacles, installing underwater piping system, searching undersea resources, underwater mine disposal operations, oceanographic surveys etc. A team from Dept. of Naval Architecture & Marine Engineering of MIST has taken a project to design a highly maneuverable unmanned underwater vehicle on the basis of quad-copter dynamics. The main objective of the research is to develop a control system for UUV which would be able to maneuver the vehicle in six DOF (Degrees of Freedom) with great ease. For this purpose we are not only focusing on controllability but also designing an efficient hull with minimal drag force & optimized propeller using CFD technique. Motors were selected on the basis of the simulated thrust generated by propellers in ANSYS Fluent software module. Settings for control parameters to carry out different types of maneuvering such as hovering, spiral, one point rotation about its centroid, gliding, rolling, drifting and zigzag motions were explained in short at the end.

  13. Determination of Toxic Metals in Little Cigar Tobacco with 'Triple Quad' ICP-MS.

    Science.gov (United States)

    Pappas, R Steven; Martone, Naudia; Gonzalez-Jimenez, Nathalie; Fresquez, Mark R; Watson, Clifford H

    2015-06-01

    Smoking remains the leading cause of preventable death in the USA. Much of the focus on harmful and potentially harmful constituents (HPHCs) in tobacco products has been on cigarettes. Little cigars gained popularity over the last decade until tobacco taxes made cigarettes more expensive in the USA. Many little cigar brands are similar in size with cigarettes and may be smoked in a similar manner. Scant data are available on HPHC concentrations in little cigars, therefore we developed and applied a new analytical method to determine concentrations of 10 toxic metals in little cigar tobacco. The method utilizes 'triple quadrupole' ICP-MS. By optimizing octapole bias, energy discrimination and cell gas flow settings, we were able to accurately quantify a range of elements including those for which the cell gas reactions were endothermic. All standard modes (Single Quad No Gas, MS-MS NH3/He and MS-MS O2) were utilized for the quantitation of 10 toxic metals in little cigar tobacco, including uranium, which was added as an analyte in the new method. Because of the elimination of interfering ions at 'shifted analyte masses', detection limits were lower compared with a previous method. Tobacco selenium concentrations were below the limit of detection in the previous method, but the new technology made it possible to report all selenium concentrations. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  14. The HBN Angle

    Directory of Open Access Journals (Sweden)

    Harsh Bhagvatiprasad Dave

    2015-01-01

    Full Text Available Aim: The purpose of this study was to establish a new cephalometric measurement, named the Harsh Bhagvatiprasad Nita angle (HBN, to assess the sagittal jaw relationship with accuracy and reproducibility. Materials and Methods: Three hundred pretreatment lateral cephalograms (100 each of Class I, II, and III were taken from the Department of Orthodontics and Dentofacial Orthopedics of Rajasthan Dental College and Hospital, Jaipur (Rajasthan and were subdivided into skeletal Class I, II, and III based on ANB, Wits appraisal, and Beta angle. This angle uses 3 skeletal landmarks the "C" (apparent axis of the condyle, "M" (midpoint of the premaxilla, and "G" (center of the largest circle that is tangent to the internal inferior, anterior, and posterior surfaces of the mandibular symphysis. Results: The result of the mean and standard deviation for the HBN angle were calculated in all three skeletal groups. After using one-way analysis of variance and post-hoc multiple comparisons by using Tukey′s honestly significant difference, homogeneous subsets, receiver operating characteristics (ROC curve - to differentiate Class II with Class I, ROC curve - to differentiate Class III with Class I, Reliability analysis with interclass correlation of HBN angle with other angles, we obtained results that showed that a patient with a HBN angle 40° and 46° can be considered to have a Class I skeletal pattern. Conclusions: A new angle, the HBN angle, was developed as a diagnostic aid to evaluate the sagittal jaw relationship more consistently. HBN angle 40° and 46° can be considered to have a Class I skeletal pattern, a more acute HBN angle indicates a Class II skeletal pattern, and a more obtuse HBN angle indicates a Class III skeletal pattern.

  15. Comparison of experimental results of a Quad-CZT array detector, a NaI(Tl), a LaBr3(Ce), and a HPGe for safeguards applications

    Science.gov (United States)

    Kwak, S.-W.; Choi, J.; Park, S. S.; Ahn, S. H.; Park, J. S.; Chung, H.

    2017-11-01

    A compound semiconductor detector, CdTe (or CdZnTe), has been used in various areas including nuclear safeguards applications. To address its critical drawback, low detection efficiency, which leads to a long measurement time, a Quad-CZT array-based gamma-ray spectrometer in our previous study has been developed by combining four individual CZT detectors. We have re-designed the developed Quad-CZT array system to make it more simple and compact for a hand-held gamma-ray detector. The objective of this paper aims to compare the improved Quad-CZT array system with the traditional gamma-ray spectrometers (NaI(Tl), LaBr3(Ce), HPGe); these detectors currently have been the most commonly used for verification of nuclear materials. Nuclear materials in different physical forms in a nuclear facility of Korea were measured by the Quad-CZT array system and the existing gamma-ray detectors. For measurements of UO2 pellets and powders, and fresh fuel rods, the Quad-CZT array system turned out to be superior to the NaI(Tl) and LaBr3(Ce). For measurements of UF6 cylinders with a thick wall, the Quad-CZT array system and HPGe gave similar accuracy under the same measurement time. From the results of the field tests conducted, we can conclude that the improved Quad-CZT array system would be used as an alternative to HPGes and scintillation detectors for the purpose of increasing effectivenss and efficiency of safeguards applications. This is the first paper employing a multi-element CZT array detector for measurement of nuclear materials—particularly uranium in a UF6 cylinder—in a real nuclear facility. The present work also suggests that the multi-CZT array system described in this study would be one promising method to address a serious weakness of CZT-based radiation detection.

  16. Reading Angles in Maps

    Science.gov (United States)

    Izard, Véronique; O'Donnell, Evan; Spelke, Elizabeth S.

    2014-01-01

    Preschool children can navigate by simple geometric maps of the environment, but the nature of the geometric relations they use in map reading remains unclear. Here, children were tested specifically on their sensitivity to angle. Forty-eight children (age 47:15-53:30 months) were presented with fragments of geometric maps, in which angle sections…

  17. Optimal reconstruction angles

    International Nuclear Information System (INIS)

    Cook, G.O. Jr.; Knight, L.

    1979-07-01

    The question of optimal projection angles has recently become of interest in the field of reconstruction from projections. Here, studies are concentrated on the n x n pixel space, where literative algorithms such as ART and direct matrix techniques due to Katz are considered. The best angles are determined in a Gauss--Markov statistical sense as well as with respect to a function-theoretical error bound. The possibility of making photon intensity a function of angle is also examined. Finally, the best angles to use in an ART-like algorithm are studied. A certain set of unequally spaced angles was found to be preferred in several contexts. 15 figures, 6 tables

  18. Photoelectric angle converter

    Science.gov (United States)

    Podzharenko, Volodymyr A.; Kulakov, Pavlo I.

    2001-06-01

    The photo-electric angle transmitter of rotation is offered, at which the output voltage is linear function of entering magnitude. In a transmitter the linear phototransducer is used on the basis of pair photo diode -- operating amplifier, which output voltage is linear function of the area of an illuminated photosensitive stratum, and modulator of a light stream of the special shape, which ensures a linear dependence of this area from an angle of rotation. The transmitter has good frequent properties and can be used for dynamic measurements of an angular velocity and angle of rotation, in systems of exact drives and systems of autocontrol.

  19. Design and System Analysis of Quad-Generation Plant Based on Biomass Gasification Integrated with District Heating

    DEFF Research Database (Denmark)

    Rudra, Souman

    This thesis presents the development of energy system for simulation, techno-economic optimization and design of a quad-generation energy system based on biomass gasification. An efficient way of reducing CO2 emission from the environment is by increasing the use of biomass in the energy sector...... alternative by upgrading existing district heating plant. It provides a generic modeling framework to design flexible energy system in near future. These frameworks address the three main issues arising in the planning and designing of energy system: a) socio impact at both planning and proses design level; b...

  20. Design and System Analysis of Quad-Generation Plant Based on Biomass Gasification Integrated with District Heating

    DEFF Research Database (Denmark)

    Rudra, Souman

    ) technical impact to select different technologies and types of equipment from available options; and c) economic concern to validate new technology with existing one. To achieve the above issues a life cycle assessment (LCA) analysis and techno-economic analysis of quad-generation system have also included...... in this study. The overall aim of this work is to provide a complete assessment of the technical potential of biomass gasification for local heat and power supply in Denmark and replace of natural gas for the production. This study also finds and defines the future areas of research in the gasification...

  1. Identification of stability and control derivatives for AS 355 L2 helicopter with Quad-M/CTA methodology

    Science.gov (United States)

    de Oliveira, Sérgio Servilha; Menegaldo, Luciano Luporini

    2012-11-01

    This work presents results obtained from a study of case for H-55 Helicopter System Identification which was carried out by an implementation of Quad-M Methodology purposed for Jategaonkar. The implementation performed was based on Cruz et al whose works were developed in Centro Técnico Aeroespacial (CTA). A comparison between Stability and Control Derivatives tables from these results and those from literature is performed for some important flight conditions. This comparison allows us to conclude about the reliability of the method, to present preliminary SCD tables for the studied aircraft and point to possible future works.

  2. Angles in hyperbolic lattices

    DEFF Research Database (Denmark)

    Risager, Morten S.; Södergren, Carl Anders

    2017-01-01

    It is well known that the angles in a lattice acting on hyperbolic n -space become equidistributed. In this paper we determine a formula for the pair correlation density for angles in such hyperbolic lattices. Using this formula we determine, among other things, the asymptotic behavior of the den......It is well known that the angles in a lattice acting on hyperbolic n -space become equidistributed. In this paper we determine a formula for the pair correlation density for angles in such hyperbolic lattices. Using this formula we determine, among other things, the asymptotic behavior...... of the density function in both the small and large variable limits. This extends earlier results by Boca, Pasol, Popa and Zaharescu and Kelmer and Kontorovich in dimension 2 to general dimension n . Our proofs use the decay of matrix coefficients together with a number of careful estimates, and lead...

  3. Output Feedback Tracking Control of an Underactuated Quad-Rotor UAV

    National Research Council Canada - National Science Library

    Lee, DongBin; Burg, Timothy; Xian, Bin; Dawson, Darren

    2006-01-01

    ...) using output feedback (OFB). Specifically, an observer is designed to estimate the velocities and an output feedback controller is designed for a nonlinear UAV system in which only position and angles are measurable...

  4. Water distribuition characteristics and soil loss of LEPA Quad-Spray emitter nozzles Características de distribuição de água e perdas de solo de bocais do emissor Quad-Spray tipo LEPA

    Directory of Open Access Journals (Sweden)

    Moises S. Ribeiro

    2013-04-01

    Full Text Available The objective of this study was to characterize water application rate, water application pattern width, flow rate, water distribution uniformity and soil loss caused by nozzles of the Low Energy Precision Aplication (LEPA type Quad-Spray emitter. The study was carried out at the Hydraulic and Irrigation Laboratory of the Department of Engineering at the Federal University of Lavras, in Lavras, state of Minas Gerais - MG, Brazil. Twenty-two (22 LEPA Quad-Spray emitter nozzles were evaluated, with nozzle diameter ranging from 1.59 to 9.92 mm. The experimental design used was entirely randomized, with three replications.Increasing values of nozzle flow rate ranging from 77.44 up to 3,044 L h-1, were obtained with increasing nozzle diameter sizes. Application pattern width ranged from 0.56 up to 3.24m, according to nozzles diameter size. Low values of CDU (maximum of 35.73% were observed when using the Quad-Spray nozzles. Observed average water application rates covered the range between 68.05 mm h-1 (the lowest value that was obtained with the 2.38mm nozzle and 258.15 mm h-1 (the highest value that was observed with the 9.92 mm. Average water application rates increased in a simple non-linear function with the increase of nozzle size diameter. However, the weighted average increase in the amount of soil loss by erosion was not related to the increase of weighted average water application values.Foi objetivo deste trabalho caracterizar a taxa de aplicação de água, largura do padrão molhado, vazão, uniformidade de distribuição de água e perdas de solo de bocais do emissor Quad-Spray tipo Low Energy Precision Aplication (LEPA. O trabalho foi realizado no Laboratório de Hidráulica e Irrigação (LHI, do Departamento de Engenharia (DEG, na Universidade Federal de Lavras (UFLA, Lavras - MG. Foram avaliados 22 bocais com diâmetro de bocal variando de 1,59 a 9,92 mm. O delineamento experimental estatístico foi o inteiramente casualizado, com

  5. Wheelchair users' experience of non-adapted and adapted clothes during sailing, quad rugby or wheel-walking.

    Science.gov (United States)

    Kratz, G; Söderback, I; Guidetti, S; Hultling, C; Rykatkin, T; Söderström, M

    1997-01-01

    The purpose of the present quasi-experimental post-test-design study was to compare 32 wheelchair users' (mostly para/tetraplegics) experience of wearing specially adapted clothes and non-adapted clothes for sailing, quad rugby or wheel-walking. Four existing assessment instruments were used: the Klein-Bell Activities of Daily Living Scale; a two-part Basic Information Questionnaire eliciting experience of effort, comfort and feeling of physical condition; the Experience Sampling Form for investigating the individuals' attitudes in terms of involvement and affective and activity mood states, and the Occupational Therapy Assessment of Leisure Time interview framework for collecting data about experience of leisure time. The wheelchair users all associated significantly greater comfort with use of the adapted clothes and, particularly the 'sailors', better physical condition. Overall, significantly greater involvement and more positive affect states were associated with the adapted clothes than with conventional garments, and mood state changed for the better. The wheelchair users set a higher priority upon work or leisure activities than upon independence in activities of daily living, and for this reason the Klein-Bell ratings showed great variation between the 'sailors' and the 'quad rugby players' (range 57%-93%), though these groups demonstrated more independence than the 'wheel-walkers'. The results of the study confirm the value of adapting sportswear for handicapped people. Such adaptations should also be of benefit for other activities than those studied.

  6. Planar n-in-n quad module prototypes for the ATLAS ITk upgrade at HL-LHC

    Science.gov (United States)

    Gisen, A.; Altenheiner, S.; Burmeister, I.; Gößling, C.; Klingenberg, R.; Kröninger, K.; Lönker, J.; Weers, M.; Wizemann, F.

    2017-12-01

    In order to meet the requirements of the High Luminosity LHC (HL-LHC), it will be necessary to replace the current tracker of the ATLAS experiment. Therefore, a new all-silicon tracking detector is being developed, the so-called Inner Tracker (ITk). The use of quad chip modules is intended in its pixel region. These modules consist of a silicon sensor that forms a unit along with four read-out chips. The current ATLAS pixel detector consists of planar n-in-n silicon pixel sensors. Similar sensors and four FE-I4 read-out chips were assembled to first prototypes of planar n-in-n quad modules. The main focus of the investigation of these modules was the region between the read-out chips, especially the central area between all four read-out chips. There are special pixel cells placed on the sensor which cover the gap between the read-out chips. This contribution focuses on the characterization of a non-irradiated device, including important sensor characteristics, charge collection determined with radioactive sources as well as hit efficiency measurements, performed in the laboratory and at testbeams. In addition, first laboratory results of an irradiated device are presented.

  7. An Approach to Speed up Single-Frequency PPP Convergence with Quad-Constellation GNSS and GIM.

    Science.gov (United States)

    Cai, Changsheng; Gong, Yangzhao; Gao, Yang; Kuang, Cuilin

    2017-06-06

    The single-frequency precise point positioning (PPP) technique has attracted increasing attention due to its high accuracy and low cost. However, a very long convergence time, normally a few hours, is required in order to achieve a positioning accuracy level of a few centimeters. In this study, an approach is proposed to accelerate the single-frequency PPP convergence by combining quad-constellation global navigation satellite system (GNSS) and global ionospheric map (GIM) data. In this proposed approach, the GPS, GLONASS, BeiDou, and Galileo observations are directly used in an uncombined observation model and as a result the ionospheric and hardware delay (IHD) can be estimated together as a single unknown parameter. The IHD values acquired from the GIM product and the multi-GNSS differential code bias (DCB) product are then utilized as pseudo-observables of the IHD parameter in the observation model. A time varying weight scheme has also been proposed for the pseudo-observables to gradually decrease its contribution to the position solutions during the convergence period. To evaluate the proposed approach, datasets from twelve Multi-GNSS Experiment (MGEX) stations on seven consecutive days are processed and analyzed. The numerical results indicate that the single-frequency PPP with quad-constellation GNSS and GIM data are able to reduce the convergence time by 56%, 47%, 41% in the east, north, and up directions compared to the GPS-only single-frequency PPP.

  8. arXiv Planar n-in-n quad module prototypes for the ATLAS ITk upgrade at HL-LHC

    CERN Document Server

    Gisen, A.; Burmeister, I.; Gößling, C.; Klingenberg, R.; Kröninger, K.; Lönker, J.; Weers, M.; Wizemann, F.

    2017-12-15

    In order to meet the requirements of the High Luminosity LHC (HL-LHC), it will be necessary to replace the current tracker of the ATLAS experiment. Therefore, a new all-silicon tracking detector is being developed, the so-called Inner Tracker (ITk). The use of quad chip modules is intended in its pixel region. These modules consist of a silicon sensor that forms a unit along with four read-out chips. The current ATLAS pixel detector consists of planar n-in-n silicon pixel sensors. Similar sensors and four FE-I4 read-out chips were assembled to first prototypes of planar n-in-n quad modules. The main focus of the investigation of these modules was the region between the read-out chips, especially the central area between all four read-out chips. There are special pixel cells placed on the sensor which cover the gap between the read-out chips. This contribution focuses on the characterization of a non-irradiated device, including important sensor characteristics, charge collection determined with radioactive so...

  9. open angle glaucoma (poag)?

    African Journals Online (AJOL)

    there is a build up of pressure due to poor outflow of aqueous humor. The outflow obstruction could occur at the trabecular meshwork of the anterior chamber angle or subsequently in the episcleral vein due to raised venous pressure. Such build up of pressure results in glaucoma . Elevated intraocular pressure remains the ...

  10. The quadriceps angle

    DEFF Research Database (Denmark)

    Miles, James Edward; Frederiksen, Jane V.; Jensen, Bente Rona

    2012-01-01

    : Pelvic limbs from red foxes (Vulpes vulpes). METHODS: Q angles were measured on hip dysplasia (HD) and whole limb (WL) view radiographs of each limb between the acetabular rim, mid-point (Q1: patellar center, Q2: femoral trochlea), and tibial tuberosity. Errors of 0.5-2.0 mm at measurement landmarks...

  11. At Right Angles

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 9. At Right Angles. Shailesh A Shirali. Information and Announcements Volume 17 Issue 9 September 2012 pp 920-920. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/017/09/0920-0920 ...

  12. The lateral angle revisited

    DEFF Research Database (Denmark)

    Morgan, Jeannie; Lynnerup, Niels; Hoppa, R.D.

    2013-01-01

    This article presents the results of a validation study of a previously published method of sex determination from the temporal bone. The purpose of this study was to evaluate the lateral angle method for the internal acoustic canal for accurately determining the sex of human skeletal remains usi...... method appears to be of minimal practical use in forensic anthropology and archeology....

  13. Small angle neutron scattering

    International Nuclear Information System (INIS)

    Gupta, Sanjay

    1982-01-01

    The technique of small angle neutron scattering was first used in Germany less than two decades ago. Since then it has developed very rapidly, and today it is regarded as one of the most powerful techniques in materials, chemical and biological research. During the last decade the combination of high flux reactors and sophisticated instrumentation has revolutionized the technique. This paper endeavours to present a brief but comprehensive review of small angle scattering of neutrons and its applications in solid state research. The domain in which small angle neutron scattering is particularly useful is delineated and some of the methods used in the analysis of data are discussed with special emphasis on recent developments. Typical small angle neutron scattering cameras are described. Finally some experimental results on heterogeneities in metallic systems (both static and dynamic studies), radiation damage in materials, superconductivity, magnetic materials and the technologically very important area of non-destructive testing are reviewed in order to illustrate the wide range of applicability of this technique to problems in solid state research. (author)

  14. Neutron small angle scattering

    International Nuclear Information System (INIS)

    Ibel, K.

    1975-01-01

    The neutron small-angle scattering system at the High-Flux Reactor in Grenoble consists of three major parts: the supply of cold neutrons via bent neutron guides; the small angle camera D11; and the data handling facilities. The camera D11 has an overall length of 80 m. The effective length of the camera is variable. The length of the collimator before the fixed sample position can be reduced by movable neutron guides; the secondary flight path of 40 m full length contains detector sites in various positions. Thus, a large domain of momentum transfers can be exploited. Scattering angles between 5.10 -4 and 0.5 rad and neutron wavelengths from 0.2 to 2.0 nm are available with the same instrument and the same relative resolution. A large-area position-sensitive detector is used which allows simultaneous recording of intensities scattered into different angles; it is a multiwire proportional chamber. 3808 elements of 1 cm 2 are arranged in a two-dimensional matrix. Future development comprises an increase of the limit in the count rate due to the electronic interface between the detector and on-line computer, actually at 5.10 4 per sec. by one order of magnitude

  15. At Right Angles

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 9. At Right Angles. Shailesh A Shirali. Information and Announcements Volume 17 Issue 9 September 2012 pp 920-920. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/017/09/0920-0920 ...

  16. A New Optimal Control Algorithm for Quad-rotor Helicopter with State Constraints via Sliding-mode Control

    Directory of Open Access Journals (Sweden)

    Zhao Jing

    2015-01-01

    Full Text Available This paper proposes a strategy of a new optimal sliding-mode control for flight control system with state constraints so that the system guarantees the optimal performance index. Besides, the strategy ensures strong robustness to the internal parametric uncertainty and the external disturbances. In order to have fast transient response speed as well as good tracking accuracy, the integral of the time multiplied by the absolute displacement tracking error is introduced as the performance index. By analyzing the state constraints which are specifically the velocity tracking error constraint and the acceleration tracking error constraint, and the performance index, the parameters of sliding-mode surface and control law are obtained. Finally, the authors conduct the semi physical simulation on Qball-X4 quad-rotor helicopter, showing the effectiveness of the proposed strategy.

  17. Relationship between the angle of repose and angle of internal ...

    African Journals Online (AJOL)

    Abstract. Click on the link to view the abstract. Keywords: Angle of repose, angle of internal friction, granular materials, triaxial compression machine, moisture content. Tanzania J. Agric. Sc. (1998) Vol.1 No.2, 187-194 ...

  18. Critical angle laser refractometer

    International Nuclear Information System (INIS)

    Castrejon-Pita, J.R.; Morales, A.; Castrejon-Garcia, R.

    2006-01-01

    A simple laser refractometer based on the detection of the critical angle for liquids is presented. The calibrated refractometer presents up to 0.000 11 of uncertainty when the refractive index is in the range between 1.300 00 and 1.340 00. The experimental setup is easy to construct and the material needed is available at most optics laboratories. The calibration method is simple and can be used in other devices. The refractive index measurements in aqueous solutions of sodium chloride were carried out to test the device and a linear dependence between the refractive index and the salt concentration was found

  19. Scaling of misorientation angle distributions

    DEFF Research Database (Denmark)

    Hughes, D.A.; Chrzan, D.C.; Liu, Q.

    1998-01-01

    The measurement of misorientation angle distributions following different amounts of deformation in cold-rolled aluminum and nickel and compressed stainless steel is reported. The sealing of the dislocation cell boundary misorientation angle distributions is studied. Surprisingly, the distributio...

  20. Angle performance on optima MDxt

    Energy Technology Data Exchange (ETDEWEB)

    David, Jonathan; Kamenitsa, Dennis [Axcelis Technologies, Inc., 108 Cherry Hill Dr, Beverly, MA 01915 (United States)

    2012-11-06

    Angle control on medium current implanters is important due to the high angle-sensitivity of typical medium current implants, such as halo implants. On the Optima MDxt, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through six narrow slits, and any angle adjustment is made by electrostatically steering the beam, while cross-wafer beam parallelism is adjusted by changing the focus of the electrostatic parallelizing lens (P-lens). In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightly tilting the wafer platen prior to implant. A variety of tests were run to measure the accuracy and repeatability of Optima MDxt's angle control. SIMS profiles of a high energy, channeling sensitive condition show both the cross-wafer angle uniformity, along with the small-angle resolution of the system. Angle repeatability was quantified by running a channeling sensitive implant as a regular monitor over a seven month period and measuring the sheet resistance-to-angle sensitivity. Even though crystal cut error was not controlled for in this case, when attributing all Rs variation to angle changes, the overall angle repeatability was measured as 0.16 Degree-Sign (1{sigma}). A separate angle repeatability test involved running a series of V-curves tests over a four month period using low crystal cut wafers selected from the same boule. The results of this test showed the angle repeatability to be <0.1 Degree-Sign (1{sigma}).

  1. Variable angle correlation spectroscopy

    International Nuclear Information System (INIS)

    Lee, Y.K.; Lawrence Berkeley Lab., CA

    1994-05-01

    In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with 13 C nuclei in rapidly rotating samples. These experiments focus on one of the basic problems in solid state NMR: how to extract the wealth of information contained in the anisotropic component of the NMR signal while still maintaining spectral resolution. Analysis of the anisotropic spectral patterns from poly-crystalline systems reveal information concerning molecular structure and dynamics, yet in all but the simplest of systems, the overlap of spectral patterns from chemically distinct sites renders the spectral analysis difficult if not impossible. One solution to this problem is to perform multi-dimensional experiments where the high-resolution, isotropic spectrum in one dimension is correlated with the anisotropic spectral patterns in the other dimensions. The VACSY technique incorporates the angle between the spinner axis and the static magnetic field as an experimental parameter that may be incremented during the course of the experiment to help correlate the isotropic and anisotropic components of the spectrum. The two-dimensional version of the VACSY experiments is used to extract the chemical shift anisotropy tensor values from multi-site organic molecules, study molecular dynamics in the intermediate time regime, and to examine the ordering properties of partially oriented samples. The VACSY technique is then extended to three-dimensional experiments to study slow molecular reorientations in a multi-site polymer system

  2. Variable angle correlation spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Kyo [Univ. of California, Berkeley, CA (United States)

    1994-05-01

    In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with 13C nuclei in rapidly rotating samples. These experiments focus on one of the basic problems in solid state NMR: how to extract the wealth of information contained in the anisotropic component of the NMR signal while still maintaining spectral resolution. Analysis of the anisotropic spectral patterns from poly-crystalline systems reveal information concerning molecular structure and dynamics, yet in all but the simplest of systems, the overlap of spectral patterns from chemically distinct sites renders the spectral analysis difficult if not impossible. One solution to this problem is to perform multi-dimensional experiments where the high-resolution, isotropic spectrum in one dimension is correlated with the anisotropic spectral patterns in the other dimensions. The VACSY technique incorporates the angle between the spinner axis and the static magnetic field as an experimental parameter that may be incremented during the course of the experiment to help correlate the isotropic and anisotropic components of the spectrum. The two-dimensional version of the VACSY experiments is used to extract the chemical shift anisotropy tensor values from multi-site organic molecules, study molecular dynamics in the intermediate time regime, and to examine the ordering properties of partially oriented samples. The VACSY technique is then extended to three-dimensional experiments to study slow molecular reorientations in a multi-site polymer system.

  3. Isolated/Non-Isolated Quad-Inverter Configuration for Multilevel Symmetrical/Asymmetrical Dual Six-Phase Star-Winding Converter

    DEFF Research Database (Denmark)

    Padmanaban, Sanjeevi Kumar; Hontz, Michael R.; Khanna, Raghav

    2016-01-01

    This article presents the developments of a novel isolated/non-isolated quad inverter configuration for multilevel dual six-phase (twelve-phase) star-winding converter. The modular circuit consists of four standard voltage source inverters (VSIs). Each VSI is incorporated with one bi-directional ......This article presents the developments of a novel isolated/non-isolated quad inverter configuration for multilevel dual six-phase (twelve-phase) star-winding converter. The modular circuit consists of four standard voltage source inverters (VSIs). Each VSI is incorporated with one bi...... converter is numerically modeled using Matlab/PLECS simulation software and the predicted behavior of the system is analyzed and presented. Good agreement is obtained between these results and the theoretical analysis. Suitable applications for the converter include (low-voltage/high-current) medium power...... systems, electrical vehicles, AC tractions, and `More-Electric Aircraft' propulsion systems....

  4. Small angle neutron scattering

    International Nuclear Information System (INIS)

    Dasannacharya, B.A.; Goyal, P.S.

    1997-01-01

    Small angle neutron scattering (SANS) is one of the most popular neutron scattering technique both for the basic research and as a tool in the hands of applied scientist. SANS is used for studying the structure of a material on a length scale of 10 - 1000 A. SANS is a diffraction experiment that involves scattering of a monocromatic beam of neutrons in order to obtain structural information about macromolecules and heterogeneities. This paper will discuss the design of SANS spectrometers with a special emphasis on the instruments which are better suited for medium flux reactors. The design of several different types of SANS spectrometers will be given. The optimization procedures and appropriate modifications to suit the budget and the space will be discussed. As an example, the design of a SANS spectrometer at CIRUS reactor Trombay will be given. (author)

  5. Positive Peer-Pressured Productivity (P-QUAD): Novel Use of Increased Transparency and a Weighted Lottery to Increase a Division's Academic Output.

    Science.gov (United States)

    Pitt, Michael B; Furnival, Ronald A; Zhang, Lei; Weber-Main, Anne M; Raymond, Nancy C; Jacob, Abraham K

    2017-03-01

    Evaluate a dual incentive model combining positive peer pressure through increased transparency of peers' academic work with a weighted lottery where entries are earned based on degree of productivity. We developed a dual-incentive peer mentoring model, Positive Peer-Pressured Productivity (P-QUAD), for faculty in the Pediatric Hospital Medicine Division at the University of Minnesota Masonic Children's Hospital. This model provided relative value-based incentives, with points assigned to different scholarly activities (eg. 1 point for abstract submission, 2 points for poster presentation, 3 points for oral presentation, etc.). These points translated into to lottery tickets for a semi-annual drawing for monetary prizes. Productivity was compared among faculty for P-QUAD year to the preintervention year. Fifteen (83%) of 18 eligible faculty members participated. Overall annual productivity per faculty member as measured by total P-QUAD score increased from a median of 3 (interquartile range [IQR] 0-14) in the preintervention year to 4 (IQR 0-27) in the P-QUAD year (P = .051). Submissions and acceptances increased in all categories except posters which were unchanged. Annual abstract submissions per faculty member significantly increased from a median of 1 (IQR 0-2) to 2 (IQR 0-2; P = .047). Seventy-three percent (8 of 11) of post-survey respondents indicated that the financial incentive motivated them to submit academic work; 100% indicated that increased awareness of their peers' work was a motivator. The combination of increased awareness of peers' academic productivity and a weighted lottery financial incentive appears to be a useful model for stimulating academic productivity in early-career faculty. Copyright © 2016 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

  6. Attitude Control of Quad-rotor by Improving the Reliability of Multi-Sensor System

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Dong Hyeon; Chong, Kil To [Chon-bok National University, Jeonju (Korea, Republic of); Park, Jong Ho [Seonam University, Namwon (Korea, Republic of); Ryu, Ji Hyoung [ETRI, Daejeon (Korea, Republic of)

    2015-05-15

    This paper presents the results of study for improving the reliability of quadrotor attitude control by applying a multi-sensor along with a data fusion algorithm. First, a mathematical model of the quadrotor dynamics was developed. Then, using the quadrotor mathematical model, simulations were performed using the improved reliability multi-sensor data as the inputs. From the simulation results, we designed a Gimbal-equipped quadrotor system. With the quadrotor in a hover state, we performed experiments according to the angle change of the user's specifications . We then calculated the attitude control data from the actual experimental data. Furthermore, with additional simulations, we verified the performance of the designed quadrotor attitude control system with multiple sensors.

  7. Unrealistic optimism, fatalism, and risk-taking in New Zealand farmers' descriptions of quad-bike incidents: a directed qualitative content analysis.

    Science.gov (United States)

    Clay, Lynne; Hay-Smith, E Jean C; Treharne, Gareth J; Milosavljevic, Stephan

    2015-01-01

    Quad-bike incidents are a major cause of occupational injury and fatality on farms warranting health and safety attention. As part of a larger study, we carried out a face-to-face survey with 216 farmers in New Zealand. We quantitatively identified farmers' propensity for risk-taking, unrealistic optimism, and fatalism as risk factors in quad-bike loss-of-control events (LCEs). The purpose of the analysis presented in this article was to use these same farmers' recollections of LCEs to explore the a priori constructs in more detail using qualitative methods. Participants reporting one or more LCEs described their first LCE and any experienced in the previous 12 months. Participants provided open-text responses about what occurred at each LCE, their reflections, and general thoughts on LCE risk factors. Directed qualitative content analysis (QCA) was used to "unpack" risk-taking, unrealistic optimism, and fatalism whilst also delineating any additional concepts that farmers associate with LCEs. Risk-taking elements were more evident than unrealistic optimism or fatalism and more suggestive of farmers finding themselves in risky situations rather than engaging in risk-seeking behavior per se. Additional inductively derived categories of fatigue/stress, multitasking, inexperience, and quad-bike faults highlight the complex nature of LCEs and the importance of risk assessment covering these concepts as well as risky situations.

  8. On the Added Value of Quad-Pol Data in a Multi-Temporal Crop Classification Framework Based on RADARSAT-2 Imagery

    Directory of Open Access Journals (Sweden)

    Arantzazu Larrañaga

    2016-04-01

    Full Text Available Polarimetric SAR images are a rich data source for crop mapping. However, quad-pol sensors have some limitations due to their complexity, increased data rate, and reduced coverage and revisit time. The main objective of this study was to evaluate the added value of quad-pol data in a multi-temporal crop classification framework based on SAR imagery. With this aim, three RADARSAT-2 scenes were acquired between May and June 2010. Once we analyzed the separability and the descriptive analysis of the features, an object-based supervised classification was performed using the Random Forests classification algorithm. Classification results obtained with dual-pol (VV-VH data as input were compared to those using quad-pol data in different polarization bases (linear H-V, circular, and linear 45°, and also to configurations where several polarimetric features (Pauli and Cloude–Pottier decomposition features and co-pol coherence and phase difference were added. Dual-pol data obtained satisfactory results, equal to those obtained with quad-pol data (in H-V basis in terms of overall accuracy (0.79 and Kappa values (0.69. Quad-pol data in circular and linear 45° bases resulted in lower accuracies. The inclusion of polarimetric features, particularly co-pol coherence and phase difference, resulted in enhanced classification accuracies with an overall accuracy of 0.86 and Kappa of 0.79 in the best case, when all the polarimetric features were added. Improvements were also observed in the identification of some particular crops, but major crops like cereals, rapeseed, and sunflower already achieved a satisfactory accuracy with the VV-VH dual-pol configuration and obtained only minor improvements. Therefore, it can be concluded that C-band VV-VH dual-pol data is almost ready to be used operationally for crop mapping as long as at least three acquisitions in dates reflecting key growth stages representing typical phenology differences of the present crops are

  9. Generalization of the Euler Angles

    Science.gov (United States)

    Bauer, Frank H. (Technical Monitor); Shuster, Malcolm D.; Markley, F. Landis

    2002-01-01

    It is shown that the Euler angles can be generalized to axes other than members of an orthonormal triad. As first shown by Davenport, the three generalized Euler axes, hereafter: Davenport axes, must still satisfy the constraint that the first two and the last two axes be mutually perpendicular if these axes are to define a universal set of attitude parameters. Expressions are given which relate the generalized Euler angles, hereafter: Davenport angles, to the 3-1-3 Euler angles of an associated direction-cosine matrix. The computation of the Davenport angles from the attitude matrix and their kinematic equation are presented. The present work offers a more direct development of the Davenport angles than Davenport's original publication and offers additional results.

  10. Target tracking control and semi-physical simulation of Qball-X4 quad-rotor unmanned aerial vehicle

    Directory of Open Access Journals (Sweden)

    Lu Liu

    2017-01-01

    Full Text Available In this article, a set of integrated ground target tracking flight system has been proposed based on the Qball-X4 quad-rotor unmanned aerial vehicle hardware platform and the QuaRC software platform. Both of the hardware and software platforms are developed by Quanser Company, Canada. The proposed tracking and positioning algorithm could be divided into several stages. First, a tracker is developed based on an optical flow method to track the target; and then, in order to improve the reliability of tracking algorithm and also help in retrieving the lost target, a cascade target detector is developed; meanwhile, a model updated scheme aiming at some possible errors in tracking and detecting process is presented based on Positive-Negative (P-N learning system; at last, a monocular visual positioning system is designed based on the corresponding navigation message. In addition, the effectiveness of the proposed flight control system is verified by both simulation and hardware-in-loop system results in several tracking flight tests.

  11. Angle Performance on Optima XE

    International Nuclear Information System (INIS)

    David, Jonathan; Satoh, Shu

    2011-01-01

    Angle control on high energy implanters is important due to shrinking device dimensions, and sensitivity to channeling at high beam energies. On Optima XE, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through a series of narrow slits, and any angle adjustment is made by steering the beam with the corrector magnet. In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightly tilting the wafer platen during implant.Using a sensitive channeling condition, we were able to quantify the angle repeatability of Optima XE. By quantifying the sheet resistance sensitivity to both horizontal and vertical angle variation, the total angle variation was calculated as 0.04 deg. (1σ). Implants were run over a five week period, with all of the wafers selected from a single boule, in order to control for any crystal cut variation.

  12. Relationship between the Angle of Repose and Angle of Internal ...

    African Journals Online (AJOL)

    ghum and rice. The angles have a big influence on the design offlow and storage structures of ... the angles of internal friction for the same grains and same moisture contents. The data ob- tained were fed into SAS statistical software for step-wise regression analysis. A model of the ..... tion, Application and Validation of En-.

  13. Small angle neutron scattering

    Directory of Open Access Journals (Sweden)

    Cousin Fabrice

    2015-01-01

    Full Text Available Small Angle Neutron Scattering (SANS is a technique that enables to probe the 3-D structure of materials on a typical size range lying from ∼ 1 nm up to ∼ a few 100 nm, the obtained information being statistically averaged on a sample whose volume is ∼ 1 cm3. This very rich technique enables to make a full structural characterization of a given object of nanometric dimensions (radius of gyration, shape, volume or mass, fractal dimension, specific area… through the determination of the form factor as well as the determination of the way objects are organized within in a continuous media, and therefore to describe interactions between them, through the determination of the structure factor. The specific properties of neutrons (possibility of tuning the scattering intensity by using the isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons make it particularly interesting in the fields of soft matter, biophysics, magnetic materials and metallurgy. In particular, the contrast variation methods allow to extract some informations that cannot be obtained by any other experimental techniques. This course is divided in two parts. The first one is devoted to the description of the principle of SANS: basics (formalism, coherent scattering/incoherent scattering, notion of elementary scatterer, form factor analysis (I(q→0, Guinier regime, intermediate regime, Porod regime, polydisperse system, structure factor analysis (2nd Virial coefficient, integral equations, characterization of aggregates, and contrast variation methods (how to create contrast in an homogeneous system, matching in ternary systems, extrapolation to zero concentration, Zero Averaged Contrast. It is illustrated by some representative examples. The second one describes the experimental aspects of SANS to guide user in its future experiments: description of SANS spectrometer, resolution of the spectrometer, optimization of

  14. Measurement of the angle gamma

    International Nuclear Information System (INIS)

    Aleksan, R.; Sphicas, P.; Massachusetts Inst. of Tech., Cambridge, MA

    1993-12-01

    The angle γ as defined in the Wolfenstein approximation is not completely out of reach of current or proposed dedicated B experiments. This work represents but a first step in the direction of extracting the third angle of the unitarity triangle by study the feasibility of using new decay modes in a hadronic machine. (A.B.). 11 refs., 1 fig., 7 tabs

  15. Nucleation of small angle boundaries

    CSIR Research Space (South Africa)

    Nabarro, FRN

    1996-12-01

    Full Text Available The internal stresses induced by the strain gradients in an array of lattice cells delineated by low-angle dislocation boundaries are partially relieved by the creation of new low-angle boundaries. This is shown to be a first-order transition...

  16. Probabilistic Assessment of Soil Moisture using C-band Quad-polarized Remote Sensing Data from RISAT1

    Science.gov (United States)

    Pal, Manali; Suman, Mayank; Das, Sarit Kumar; Maity, Rajib

    2017-04-01

    Information on spatio-temporal distribution of surface Soil Moisture Content (SMC) is essential in several hydrological, meteorological and agricultural applications. There has been increasing importance of microwave active remote sensing data for large-scale estimation of surface SMC because of its ability to monitor spatial and temporal variation of surface SMC at regional, continental and global scale at a reasonably fine spatial and temporal resolution. The use of Synthetic Aperture Radar (SAR) is highly potential for catchment-scale applications due to high spatial resolution (˜10-20 m) both for vegetated and bare soil surface as well as because of its all-weather and day and night characteristics. However, one prime disadvantage of SAR is that their signal is subjective to SMC along with Land Use Land Cover (LULC) and surface roughness conditions, making the retrieval of SMC from SAR data an "ill-posed" problem. Moreover, the quantification of uncertainty due to inappropriate surface roughness characterization, soil texture, inversion techniques etc. even in the latest established retrieval methods, is little explored. This paper reports a recently developed method to estimate the surface SMC with probabilistic assessment of uncertainty associated with the estimation (Pal et al., 2016). Quad-polarized SAR data from Radar Imaging Satellite1 (RISAT1), launched in 2012 by Indian Space Research Organization (ISRO) and information on LULC regarding bareland and vegetated land (IEEE Transactions on Geoscience and Remote Sensing, In Press, doi:10.1109/TGRS.2016.2623378. Zribi, M., Baghdadi, N., Holah, N., and Fafin, O., (2005)."New methodology for soil surface moisture estimation and its application to ENVISAT-ASAR multi-incidence data inversion." Remote Sensing of Environment, vol. 96, nos. 3-4, pp. 485-496.

  17. Artificial eye amplitudes and characteristics in enucleated socket with porous polyethylene spherical and quad-motility implant Amplitude de movimento e características das próteses oculares em cavidades enucleadas com implante de polietileno poroso esférico e "quad-motility"

    Directory of Open Access Journals (Sweden)

    Lucia Miriam Dumont Lucci

    2007-10-01

    Full Text Available PURPOSE: To compare artificial eye amplitudes in enucleated socket with porous polyethylene either spherical or quad-motility implant and study the characteristics of artificial eyes fit with the two orbital implants. METHODS: A total of 21 patients were prospectively studied who underwent enucleation because of an intraocular melanoma and the randomization defined a porous polyethylene either spherical or quad-motility orbital implant. Measurements of the amplitude of the artificial eye were obtained with prism and digital photos. The software Scion Image analyzed the digital photos (www.scioncorp.com and the quantitative data were allocated to groups. The measurements (height, length, thickness and weight of the 21 artificial eyes were analyzed. Student's t-test was performed to determine the significance of difference between groups (p0.05 for all directions. On analyzing the digital photos, the artificial eye with spherical implant showed higher artificial eye amplitude downward (p=0.009 among patients older than 55 years old, rightward (p=0.036 and downward (p=0.008 among the 9 patients with enucleated right eye. Height and length were similar in the 21 artificial eyes but those artificial eyes fit with quad-motility orbital implants were statistically significant thicker (pOBJETIVOS: Comparar a amplitude de movimento da prótese ocular em cavidade enucleada e com implante orbitário esférico e "quad-motility" e estudar as características das próteses oculares adaptadas com os dois modelos de implantes orbitários. MÉTODOS: Vinte e um pacientes foram prospectivamente estudados após a enucleação devido a melanoma intra-ocular e cuja randomização definiu o implante orbitário de polietileno poroso nos modelos esférico e "quad-motility". Medidas da amplitude da prótese ocular foram obtidas com prisma e fotografia digital. O programa Scion Image analisou as fotos digitais (www.scioncorp.com e os resultados foram distribuídos por

  18. Observations at large zenith angles

    CERN Document Server

    Schroeder, F

    2000-01-01

    Cherenkov telescope observations at zenith angles >70 deg. are capable of providing large collection areas for high energy gamma-induced air showers. In order to provide a full Monte Carlo simulation of the large zenith angle observations the air shower simulation code CORSIKA was modified to treat particles in a curved geometry. First results of studies with the stand alone telescope HEGRA CT1 are presented.

  19. A comparison of three-dimensional stress distribution and displacement of naso-maxillary complex on application of forces using quad-helix and nickel titanium palatal expander 2 (NPE2: a FEM study

    Directory of Open Access Journals (Sweden)

    Avinash Kumar

    2016-06-01

    Full Text Available Abstract Background Our objectives are to analyse and to compare the stress distribution and displacement of the craniofacial structures, following the application of forces from quad-helix and Nickel Titanium Palatal Expander-2 (NPE2 using finite element analysis. Methods Three-dimensional finite element models of young dried human skull, quad-helix appliance and NPE2 were constructed, and the initial activation of the expanders was stimulated to carry out the analysis and to evaluate the Von Misses stresses and displacement. Results Both the models demonstrated the highest stresses at the mid-palatal suture, with maximum posterior dislocation. The second highest stress was recorded at the fronto-zygomatic suture. The pattern of stress distribution was almost similar in both the groups, but NPE2 revealed lower magnitude stresses than quad-helix. The only exception being quad-helix model showed high stress levels around pterygo-maxillary suture whereas minimal stress around pterygo-maxillary suture was noticed after NPE2 activation. The cusp of the erupting canine and the erupting mesiobuccal cusp of the second molar showed outward, backward and downward displacement signifying increase in their eruption pattern following maxillary expansion. Conclusions Maxillary expansion using quad-helix and NPE2 can be used in posterior crossbite correction in cases where maximum skeletal changes are desirable at a younger age; it is furthermore effective in treating young patients with impacted or displaced teeth. Quad-helix and NPE2 produced acceptable forces for orthopaedic treatment even after being orthodontic appliances; their clinical application should be correctly planned as the effects of these appliances are largely age dependent.

  20. Effects of slant angle and illumination angle on MTF estimations

    CSIR Research Space (South Africa)

    Vhengani, LM

    2012-07-01

    Full Text Available angle d(?) was not constant. It was also noted that the iris of the imaging system was in most cases adjusted during initial setups of each measurements. After each measurement, the knife-edge target was replaced with the ISO 12233 MTF target (shown....085 0.09 0.095 K:\\Working Folder\\Project_On_orbit MTF\\edgetargets\\MTF_Lab_Measurements _20120302_Edge Slant Angle (degrees) Ny qu ist MT F (c yc le/p ixe l) Data Regression -18 -16 -14 -12 -10 -8 -6 -4 -2 0.05 0.055 0.06 0...

  1. On the classification of mixed floating pollutants on the Yellow Sea of China by using a quad-polarized SAR image

    Science.gov (United States)

    Wang, Xiaochen; Shao, Yun; Tian, Wei; Li, Kun

    2017-09-01

    This study explored different methodologies using a C-band RADARSAT-2 quad-polarized Synthetic Aperture Radar (SAR) image located over China's Yellow Sea to investigate polarization decomposition parameters for identifying mixed floating pollutants from a complex ocean background. It was found that solitary polarization decomposition did not meet the demand for detecting and classifying multiple floating pollutants, even after applying a polarized SAR image. Furthermore, considering that Yamaguchi decomposition is sensitive to vegetation and the algal variety Enteromorpha prolifera, while H/A/alpha decomposition is sensitive to oil spills, a combination of parameters which was deduced from these two decompositions was proposed for marine environmental monitoring of mixed floating sea surface pollutants. A combination of volume scattering, surface scattering, and scattering entropy was the best indicator for classifying mixed floating pollutants from a complex ocean background. The Kappa coefficients for Enteromorpha prolifera and oil spills were 0.7514 and 0.8470, respectively, evidence that the composite polarized parameters based on quad-polarized SAR imagery proposed in this research is an effective monitoring method for complex marine pollution.

  2. Frequency scaling for angle gathers

    KAUST Repository

    Zuberi, M. A H

    2014-01-01

    Angle gathers provide an extra dimension to analyze the velocity after migration. Space-shift and time shift-imaging conditions are two methods used to obtain angle gathers, but both are reasonably expensive. By scaling the time-lag axis of the time-shifted images, the computational cost of the time shift imaging condition can be considerably reduced. In imaging and more so Full waveform inversion, frequencydomain Helmholtz solvers are used more often to solve for the wavefields than conventional time domain extrapolators. In such cases, we do not need to extend the image, instead we scale the frequency axis of the frequency domain image to obtain the angle gathers more efficiently. Application on synthetic data demonstrate such features.

  3. Temperature dependence of Brewster's angle.

    Science.gov (United States)

    Guo, Wei

    2018-01-01

    In this work, a dielectric at a finite temperature is modeled as an ensemble of identical atoms moving randomly around where they are trapped. Light reflection from the dielectric is then discussed in terms of atomic radiation. Specific calculation demonstrates that because of the atoms' thermal motion, Brewster's angle is, in principle, temperature-dependent, and the dependence is weak in the low-temperature limit. What is also found is that the Brewster's angle is nothing but a result of destructive superposition of electromagnetic radiation from the atoms.

  4. Angle independent velocity spectrum determination

    DEFF Research Database (Denmark)

    2014-01-01

    An ultrasound imaging system (100) includes a transducer array (102) that emits an ultrasound beam and produces at least one transverse pulse-echo field that oscillates in a direction transverse to the emitted ultrasound beam and that receive echoes produced in response thereto and a spectral vel...... velocity estimator (110) that determines a velocity spectrum for flowing structure, which flows at an angle of 90 degrees and flows at angles less than 90 degrees with respect to the emitted ultrasound beam, based on the received echoes....

  5. Tiny incident light angle sensor

    Science.gov (United States)

    Mitrenga, D.; Schädel, M.; Winzer, A. T.; Völlmeke, S.; Preuß, K. D.; Freitag, J.; Brodersen, O.

    2017-05-01

    A novel device for detecting the intensity and the angles of incoming light is presented. The silicon chip with 1 mm edge length comprises a segmented photo diode with four active areas within the inclined surfaces of a deep etched cavity. Simple signal difference analysis of these signals allow for accurate azimuth and inclination measurement in the range of 0 to 360° and 0 to 55°, respectively. Using an artificial neural network (ANN) calibration strategy the operation range of inclination can be increased up to 85° with typical angle errors below 2°. In this report we present details on design, fabrication, signal analysis and calibration strategies.

  6. QUAD4 Seminar. Revision

    Science.gov (United States)

    1993-04-01

    OR jANIZATION (If applicable) Flight Dynamics Laboratory JWRDC/ FIBRA N/A Bc. ADDRESS (City, State, and ZIP Code) 10 SOURCE OF FUNDING NUMBERS 0...wish to be removed from our mailing list, or if the addressee is no longer employed by your organization please notify W RDC/ FIBRA . WPAFB, OH 45433...8217-’- -4 4- r- F-. C>. to.F.. CO CO j CO COCO 1- 0 ’.0 ’.0 re0.. C>0’ 0’. (7’ fn 0M. o.7’ (’d’. (𔃾’. (’ (’ 4 4") en en t. o " x0r COCCOOCCO’z𔃺L0𔃺 r- m C

  7. A Hitch Angle Measurement Device

    National Research Council Canada - National Science Library

    Von

    1998-01-01

    As part of a project to demonstrate that an unmanned ground vehicle (UGV) could remotely back up with a trailer, a simple proof-of-concept device was designed to measure the angle between a high-mobility multipurpose wheeled vehicle (HMMWV...

  8. ASSESMENT AND EVLUATION OF THE IMPACT OF USING POLSAR IMAGERIES WITH DIFERENT INCIDENT ANGLES IN FOREST CLASSIFICATION

    Directory of Open Access Journals (Sweden)

    K. Ranjbar

    2013-09-01

    Full Text Available Forests are a dominant biome of the earth and have an important impact on its economic and environmental well-being. Forestry applications of radar remote sensing are addressed in the context of both forest management and ecosystem understanding, modelling and monitoring. Nowadays, radar remote sensing is being used for a lot of applications in various fields. Due to the applications of polarimetric radar in recent decades, many researchers have tended to this field. One of the main advantages of SAR images is that these images are independent over the time (day and night and weather condition. The polarimetric SAR (POLSAR images compared with other remote sensing images are more informative. Classification of radar images is a way by which we can separate different types of forest species. In addition to the main characteristics of the target, the backscatter from a SAR image is widely dependant on various radar system parameters. One of these system parameters is the incident angle of the radar system. In this paper, the impact of using PolSAR images with different incidence angles for the classification of forest areas is investigated. Two polSAR images with different incident angles taken by RADARSAT-2 in fine quad polarized mode (FQ4 and FQ18 have been used in this study. The study area is located in the Petawawa Research Forest (PRF near Chalk River, Ontario, Canada The methodology of this paper contains three steps: (1 preprocessing, (2 wishart classification and (3 evaluating & analyzing the results. The preprocessing steps consist of the speckle noise filtering, covariance matrix extraction and georeferencing. In the second step, each incidence angle image was classified by using the supervised Wishart classification. The Wishart classification method has the capability of having multiple images at the same time. Thus, in the next experiment the classification was performed using both incidence angle images. Finally, the obtained

  9. Assesment and Evluation of the Impact of Using Polsar Imageries with Diferent Incident Angles in Forest Classification

    Science.gov (United States)

    Ranjbar, K.; Maghsoudi, Y.; Sahebi, M. R.

    2013-09-01

    Forests are a dominant biome of the earth and have an important impact on its economic and environmental well-being. Forestry applications of radar remote sensing are addressed in the context of both forest management and ecosystem understanding, modelling and monitoring. Nowadays, radar remote sensing is being used for a lot of applications in various fields. Due to the applications of polarimetric radar in recent decades, many researchers have tended to this field. One of the main advantages of SAR images is that these images are independent over the time (day and night) and weather condition. The polarimetric SAR (POLSAR) images compared with other remote sensing images are more informative. Classification of radar images is a way by which we can separate different types of forest species. In addition to the main characteristics of the target, the backscatter from a SAR image is widely dependant on various radar system parameters. One of these system parameters is the incident angle of the radar system. In this paper, the impact of using PolSAR images with different incidence angles for the classification of forest areas is investigated. Two polSAR images with different incident angles taken by RADARSAT-2 in fine quad polarized mode (FQ4 and FQ18) have been used in this study. The study area is located in the Petawawa Research Forest (PRF) near Chalk River, Ontario, Canada The methodology of this paper contains three steps: (1) preprocessing, (2) wishart classification and (3) evaluating & analyzing the results. The preprocessing steps consist of the speckle noise filtering, covariance matrix extraction and georeferencing. In the second step, each incidence angle image was classified by using the supervised Wishart classification. The Wishart classification method has the capability of having multiple images at the same time. Thus, in the next experiment the classification was performed using both incidence angle images. Finally, the obtained results from each

  10. Measurement of the angle gamma

    International Nuclear Information System (INIS)

    Aleksan, R.; Kayser, B.; Sphicas, P.

    1993-01-01

    The angle γ at least as defined in the Wolfenstein approximation is not completely out of reach of current or proposed dedicated B experiments. This conclusion certainly depends crucially on the assumed trigger and tagging efficiencies and also on the expected backgrounds. The work summarized here represents but a first step in the direction of extracting the third angle of the unitarity triangle. The theoretical developments during the workshop have resulted in a clearer understanding of the quantities studied. On the experimental side, new decay modes (i.e. in addition to the traditional ρK s decay) have resulted in expections for observing CP violation in B s decays which are not unreasonable. It is conceivable that a dedicated B experiment can probe a fundamental aspect of the Standard Model, the CKM matrix, in multiple ways. In the process, new physics can appear anywhere along the line

  11. Contact angles on stretched solids

    Science.gov (United States)

    Mensink, Liz; Snoeijer, Jacco

    2017-11-01

    The surface energy of solid interfaces plays a central role in wetting, as they dictate the liquid contact angle. Yet, it has been challenging to measure the solid surface energies independently, without making use of Young's law. Here we present Molecular Dynamics (MD) simulations by which we measure the surface properties for all interfaces, including the solids. We observe change in contact angles upon stretching the solid substrates, showing that the surface energy is actually strain dependent. This is clear evidence of the so-called Shuttleworth effect, making it necessary to distinguish surface energy from surface tension. We discuss how this effect gives rise to a new class of elasto-capillary phenomena. ERC Consolidator Grant No. 616918.

  12. LHC Report: playing with angles

    CERN Multimedia

    Mike Lamont for the LHC team

    2016-01-01

    Ready (after a machine development period), steady (running), go (for a special run)!   The crossing angles are an essential feature of the machine set-up. They have to be big enough to reduce the long-range beam-beam effect. The LHC has recently enjoyed a period of steady running and managed to set a new record for “Maximum Stable Luminosity Delivered in 7 days” of 3.29 fb-1 between 29 August and 4 September. The number of bunches per beam remains pegged at 2220 because of the limitations imposed by the SPS beam dump. The bunch population is also somewhat reduced due to outgassing near one of the injection kickers at point 8. Both limitations will be addressed during the year-end technical stop, opening the way for increased performance in 2017. On 10 and 11 September, a two day machine development (MD) period took place. The MD programme included a look at the possibility of reducing the crossing angle at the high-luminosity interaction points. The crossing angles are an ess...

  13. Ocular biometry in angle closure.

    Science.gov (United States)

    Razeghinejad, Mohammad Reza; Banifatemi, Mohammad

    2013-01-01

    To compare ocular biometric parameters in primary angle closure suspects (PACS), primary angle closure glaucoma (PACG) and acute primary angle closure (APAC). This cross-sectional study was performed on 113 patients including 33 cases of PACS, 45 patients with PACG and 35 subjects with APAC. Central corneal thickness (CCT), axial length (AL), anterior chamber depth (ACD) and lens thickness (LT) were measured with an ultrasonic biometer. Lens-axial length factor (LAF), relative lens position, corrected ACD (CACD) and corrected lens position were calculated. The parameters were measured bilaterally but only data from the right eyes were compared. In the APAC group, biometric parameters were also compared between affected and unaffected fellow eyes. Logistic regression analysis was performed to identify risk factors. No statistically significant difference was observed in biometric parameters between PACS and PACG eyes, or between affected and fellow eyes in the APAC group (P>0.05 for all comparisons). However, eyes with APAC had thicker cornea (P=0.001), thicker lens (PAPAC. In the APAC group, LAF (PAPAC.

  14. Light Scattering at Various Angles

    Science.gov (United States)

    Latimer, Paul; Pyle, B. E.

    1972-01-01

    The Mie theory of scattering is used to provide new information on how changes in particle volume, with no change in dry weight, should influence light scattering for various scattering angles and particle sizes. Many biological cells (e.g., algal cells, erythrocytes) and large subcellular structures (e.g., chloroplasts, mitochondria) in suspension undergo this type of reversible volume change, a change which is related to changes in the rates of cellular processes. A previous study examined the effects of such volume changes on total scattering. In this paper scattering at 10° is found to follow total scattering closely, but scattering at 45°, 90°, 135°, and 170° behaves differently. Small volume changes can cause very large observable changes in large angle scattering if the sample particles are uniform in size; however, the natural particle size heterogeneity of most samples would mask this effect. For heterogeneous samples of most particle size ranges, particle shrink-age is found to increase large angle scattering. PMID:4556610

  15. Angle comparison using an autocollimator

    Science.gov (United States)

    Geckeler, Ralf D.; Just, Andreas; Vasilev, Valentin; Prieto, Emilio; Dvorácek, František; Zelenika, Slobodan; Przybylska, Joanna; Duta, Alexandru; Victorov, Ilya; Pisani, Marco; Saraiva, Fernanda; Salgado, Jose-Antonio; Gao, Sitian; Anusorn, Tonmueanwai; Leng Tan, Siew; Cox, Peter; Watanabe, Tsukasa; Lewis, Andrew; Chaudhary, K. P.; Thalmann, Ruedi; Banreti, Edit; Nurul, Alfiyati; Fira, Roman; Yandayan, Tanfer; Chekirda, Konstantin; Bergmans, Rob; Lassila, Antti

    2018-01-01

    Autocollimators are versatile optical devices for the contactless measurement of the tilt angles of reflecting surfaces. An international key comparison (KC) on autocollimator calibration, EURAMET.L-K3.2009, was initiated by the European Association of National Metrology Institutes (EURAMET) to provide information on the capabilities in this field. The Physikalisch-Technische Bundesanstalt (PTB) acted as the pilot laboratory, with a total of 25 international participants from EURAMET and from the Asia Pacific Metrology Programme (APMP) providing measurements. This KC was the first one to utilise a high-resolution electronic autocollimator as a standard. In contrast to KCs in angle metrology which usually involve the full plane angle, it focused on relatively small angular ranges (+/-10 arcsec and +/-1000 arcsec) and step sizes (10 arcsec and 0.1 arcsec, respectively). This document represents the approved final report on the results of the KC. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  16. Ocular Biometry in Angle Closure

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Razeghinejad

    2013-01-01

    Full Text Available Purpose: To compare ocular biometric parameters in primary angle closure suspects (PACS, primary angle closure glaucoma (PACG and acute primary angle closure (APAC. Methods: This cross-sectional study was performed on 113 patients including 33 cases of PACS, 45 patients with PACG and 35 subjects with APAC. Central corneal thickness (CCT, axial length (AL, anterior chamber depth (ACD and lens thickness (LT were measured with an ultrasonic biometer. Lens-axial length factor (LAF, relative lens position, corrected ACD (CACD and corrected lens position were calculated. The parameters were measured bilaterally but only data from the right eyes were compared. In the APAC group, biometric parameters were also compared between affected and unaffected fellow eyes. Logistic regression analysis was performed to identify risk factors. Results: No statistically significant difference was observed in biometric parameters between PACS and PACG eyes, or between affected and fellow eyes in the APAC group (P>0.05 for all comparisons. However, eyes with APAC had thicker cornea (P=0.001, thicker lens (P<0.0001, shallower ACD (P=0.009, shallower CACD (P=0.003 and larger LAF (P<0.0001. Based on ROC curve analysis, lower ACD, and larger LT, LAF and CCT values were associated with APAC. In the APAC group, LAF (P<0.0001 and CCT (P=0.001 were significant risk factors. Conclusion: This study revealed no significant difference in biometric characteristics in eyes with PACS and PACG. However, larger LAF and CCT were predictive of APAC.

  17. Small angle scattering and polymers

    Energy Technology Data Exchange (ETDEWEB)

    Cotton, J.P. [Laboratoire Leon Brillouin (LLB) - Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France)

    1996-12-31

    The determination of polymer structure is a problem of interest for both statistical physics and industrial applications. The average polymer structure is defined. Then, it is shown why small angle scattering, associated with isotopic substitution, is very well suited to the measurement of the chain conformation. The corresponding example is the old, but pedagogic, measurement of the chain form factor in the polymer melt. The powerful contrast variation method is illustrated by a recent determination of the concentration profile of a polymer interface. (author) 12 figs., 48 refs.

  18. Contact Angle Measurement in Lattice Boltzmann Method

    OpenAIRE

    Wen, Binghai; Huang, Bingfang; Qin, Zhangrong; Wang, Chunlei; Zhang, Chaoying

    2017-01-01

    Contact angle is an essential characteristic in wetting, capillarity and moving contact line; however, although contact angle phenomena are effectively simulated, an accurate and real-time measurement for contact angle has not been well studied in computational fluid dynamics, especially in dynamic environments. Here, we design a geometry-based mesoscopic scheme to onthesport measure the contact angle in the lattice Boltzmann method. The computational results without gravity effect are in exc...

  19. 30 CFR 56.19037 - Fleet angles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fleet angles. 56.19037 Section 56.19037 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Sheaves § 56.19037 Fleet angles. Fleet angles on hoists installed after November 15, 1979, shall not be...

  20. 30 CFR 57.19037 - Fleet angles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fleet angles. 57.19037 Section 57.19037 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Sheaves § 57.19037 Fleet angles. Fleet angles on hoists installed after November 15, 1979, shall not be...

  1. Lateral angle and cranial base sexual dimorphism

    DEFF Research Database (Denmark)

    Duquesnel Mana, Mathilde; Adalian, Pascal; Lynnerup, Niels

    2016-01-01

    , to examine sexual dimorphism in the relationship between the lateral angle and cranial base shape. The lateral angle method was tested using a forensic sample of 102 CT scans of the head with known sex. We measured the angle using two methods: measurements directly on the CT slide, the method usually applied...

  2. Small-angle scattering, topography and radiography

    International Nuclear Information System (INIS)

    Schelten, J.

    1978-01-01

    A table is given showing scattering and imaging methods for X-rays and neutrons, followed, by a discussion of such topics as 1. Radiography 2. Topography 3. Small-angle scattering 3.1. The differential cross section 3.2. Comparison of X-ray and neutron small-angle scattering 3.3. Examples of small-angle scattering. (orig.) [de

  3. The Q-angle and sport

    DEFF Research Database (Denmark)

    Hahn, Thomas; Foldspang, Anders

    1997-01-01

    Quadriceps muscle contraction tends to straighten the Q angle. We expected that sports comprising a high amount of quadriceps training could be associated with low Q angles. The aim of the present study was to estimate the Q angle in athletes and to investigate its potential associations with par......Quadriceps muscle contraction tends to straighten the Q angle. We expected that sports comprising a high amount of quadriceps training could be associated with low Q angles. The aim of the present study was to estimate the Q angle in athletes and to investigate its potential associations...... with participation in sport. Three hundred and thirty-nine athletes had their Q angle measured. The mean of right-side Q angles was higher than left side, and the mean Q angle was higher in women than in men. The Q angle was positively associated with years of jogging, and negatively with years of soccer, swimming...... and sports participation at all. It is concluded that the use of Q angle measurements is questionable....

  4. Individualized optimal release angles in discus throwing.

    Science.gov (United States)

    Leigh, Steve; Liu, Hui; Hubbard, Mont; Yu, Bing

    2010-02-10

    The purpose of this study was to determine individualized optimal release angles for elite discus throwers. Three-dimensional coordinate data were obtained for at least 10 competitive trials for each subject. Regression relationships between release speed and release angle, and between aerodynamic distance and release angle were determined for each subject. These relationships were linear with subject-specific characteristics. The subject-specific relationships between release speed and release angle may be due to subjects' technical and physical characteristics. The subject-specific relationships between aerodynamic distance and release angle may be due to interactions between the release angle, the angle of attack, and the aerodynamic distance. Optimal release angles were estimated for each subject using the regression relationships and equations of projectile motion. The estimated optimal release angle was different for different subjects, and ranged from 35 degrees to 44 degrees . The results of this study demonstrate that the optimal release angle for discus throwing is thrower-specific. The release angles used by elite discus throwers in competition are not necessarily optimal for all discus throwers, or even themselves. The results of this study provide significant information for understanding the biomechanics of discus throwing techniques. Copyright 2009 Elsevier Ltd. All rights reserved.

  5. Wafer scale oblique angle plasma etching

    Science.gov (United States)

    Burckel, David Bruce; Jarecki, Jr., Robert L.; Finnegan, Patrick Sean

    2017-05-23

    Wafer scale oblique angle etching of a semiconductor substrate is performed in a conventional plasma etch chamber by using a fixture that supports a multiple number of separate Faraday cages. Each cage is formed to include an angled grid surface and is positioned such that it will be positioned over a separate one of the die locations on the wafer surface when the fixture is placed over the wafer. The presence of the Faraday cages influences the local electric field surrounding each wafer die, re-shaping the local field to be disposed in alignment with the angled grid surface. The re-shaped plasma causes the reactive ions to follow a linear trajectory through the plasma sheath and angled grid surface, ultimately impinging the wafer surface at an angle. The selected geometry of the Faraday cage angled grid surface thus determines the angle at with the reactive ions will impinge the wafer.

  6. Angle closure glaucoma secondary to psychotropic medications

    Directory of Open Access Journals (Sweden)

    John Ross Rocke

    2017-07-01

    Full Text Available Background Psychotropic medications are commonly associated anticholinergic side-effects. In susceptible patients, this can result in angle closure induced permanent loss of vision Aims To review the mechanism of angle closure and which psychotropics are most likely to precipitate this complication. Methods Literature review surrounding the mechanism of angle closure and pharmacology of various psychotropics Results Mydriasis, forward-displacement of the lens-iris diaphragm and ciliary body swelling are the mechanisms by which angle closure occurs. Anticholinergic side effects of psychotropic medications are most implicated in causing this. Conclusion Screening patients for risk factors of angle closure and either having them formally assessed or choosing psychotropics with minimal anticholinergic effects may avoid inducing angle closure.

  7. Investigation of quad-energy high-rate photon counting for X-ray computed tomography using a cadmium telluride detector.

    Science.gov (United States)

    Matsukiyo, Hiroshi; Sato, Eiichi; Oda, Yasuyuki; Yamaguchi, Satoshi; Sato, Yuichi; Hagiwara, Osahiko; Enomoto, Toshiyuki; Watanabe, Manabu; Kusachi, Shinya

    2017-12-01

    To obtain four kinds of tomograms at four different X-ray energy ranges simultaneously, we have constructed a quad-energy (QE) X-ray photon counter with a cadmium telluride (CdTe) detector and four sets of comparators and microcomputers (MCs). X-ray photons are detected using the CdTe detector, and the event pulses produced using amplifiers are sent to four comparators simultaneously to regulate four threshold energies of 20, 33, 50 and 65keV. Using this counter, the energy ranges are 20-33, 33-50, 50-65 and 65-100keV; the maximum energy corresponds to the tube voltage. We performed QE computed tomography (QE-CT) at a tube voltage of 100kV. Using a 0.5-mm-diam lead pinhole, four tomograms were obtained simultaneously at four energy ranges. K-edge CT using iodine and gadolinium media was carried out utilizing two energy ranges of 33-50 and 50-65keV, respectively. At a tube voltage of 100kV and a current of 60 μA, the count rate was 15.2 kilocounts per second (kcps), and the minimum count rates after penetrating objects in QE-CT were regulated to approximately 2 kcps by the tube current. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Body of Knowledge (BOK) for Leadless Quad Flat No-Lead/bottom Termination Components (QFN/BTC) Package Trends and Reliability

    Science.gov (United States)

    Ghaffarian, Reza

    2014-01-01

    Bottom terminated components and quad flat no-lead (BTC/QFN) packages have been extensively used by commercial industry for more than a decade. Cost and performance advantages and the closeness of the packages to the boards make them especially unique for radio frequency (RF) applications. A number of high-reliability parts are now available in this style of package configuration. This report presents a summary of literature surveyed and provides a body of knowledge (BOK) gathered on the status of BTC/QFN and their advanced versions of multi-row QFN (MRQFN) packaging technologies. The report provides a comprehensive review of packaging trends and specifications on design, assembly, and reliability. Emphasis is placed on assembly reliability and associated key design and process parameters because they show lower life than standard leaded package assembly under thermal cycling exposures. Inspection of hidden solder joints for assuring quality is challenging and is similar to ball grid arrays (BGAs). Understanding the key BTC/QFN technology trends, applications, processing parameters, workmanship defects, and reliability behavior is important when judicially selecting and narrowing the follow-on packages for evaluation and testing, as well as for the low risk insertion in high-reliability applications.

  9. Investigation of 2D photonic crystal structure based channel drop filter using quad shaped photonic crystal ring resonator for CWDM system

    Energy Technology Data Exchange (ETDEWEB)

    Chhipa, Mayur Kumar, E-mail: mayurchhipa1@gmail.com; Dusad, Lalit Kumar [Government Engineering College Ajmer, Rajasthan (India); Rajasthan Technical University, Kota, Rajasthan (India)

    2016-05-06

    In this paper, the design & performance of two dimensional (2-D) photonic crystal structure based channel drop filter is investigated using quad shaped photonic crystal ring resonator. In this paper, Photonic Crystal (PhC) based on square lattice periodic arrays of Gallium Indium Phosphide (GaInP) rods in air structure have been investigated using Finite Difference Time Domain (FDTD) method and photonic band gap is being calculated using Plane Wave Expansion (PWE) method. The PhC designs have been optimized for telecommunication wavelength λ= 1571 nm by varying the rods lattice constant. The number of rods in Z and X directions is 21 and 20, with lattice constant 0.540 nm it illustrates that the arrangement of Gallium Indium Phosphide (GaInP) rods in the structure which gives the overall size of the device around 11.4 µm × 10.8 µm. The designed filter gives good dropping efficiency using 3.298, refractive index. The designed structure is useful for CWDM systems. This device may serve as a key component in photonic integrated circuits. The device is ultra compact with the overall size around 123 µm{sup 2}.

  10. Direct angle resolved photoemission spectroscopy and ...

    Indian Academy of Sciences (India)

    Keywords. Condensed matter physics; high-c superconductivity; electronic properties; photoemission spectroscopy; angle resolved photoemission spectroscopy; cuprates; films; strain; pulsed laser deposition.

  11. 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 concluded...

  12. Gaugings at angles from orientifold reductions

    International Nuclear Information System (INIS)

    Roest, Diederik

    2009-01-01

    We consider orientifold reductions to N= 4 gauged supergravity in four dimensions. A special feature of this theory is that different factors of the gauge group can have relative angles with respect to the electro-magnetic SL(2) symmetry. These are crucial for moduli stabilization and de Sitter vacua. We show how such gaugings at angles generically arise in orientifold reductions.

  13. Custom total occlusal convergence angle sticker fabrication.

    Science.gov (United States)

    Cho, Seok-Hwan; Nagy, William W

    2015-09-01

    This article describes a method of fabricating a custom total occlusal convergence angle sticker with photo editing software and label stickers. The custom total occlusal convergence angle sticker can help clinicians achieve an accurate degree of taper during axial wall reduction of tooth preparation. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  14. Practical evaluation of action-angle variables

    International Nuclear Information System (INIS)

    Boozer, A.H.

    1984-02-01

    A practical method is described for establishing action-angle variables for a Hamiltonian system. That is, a given nearly integrable Hamiltonian is divided into an exactly integrable system plus a perturbation in action-angle form. The transformation of variables, which is carried out using a few short trajectory integrations, permits a rapid determination of trajectory properties throughout a phase space volume

  15. Acute angle closure glaucoma following ileostomy surgery

    Directory of Open Access Journals (Sweden)

    Mariana Meirelles Lopes

    2015-02-01

    Full Text Available Angle-closure glaucoma can be induced by drugs that may cause pupillary dilatation. We report a case of a patient that developed bilateral angle closure glaucoma after an ileostomy surgery because of systemic atropine injection. This case report highlights the importance of a fast ophthalmologic evaluation in diseases with ocular involvement in order to make accurate diagnoses and appropriate treatments.

  16. Solid angles III. The role of conformers in solid angle calculations

    CSIR Research Space (South Africa)

    White, D

    1995-06-14

    Full Text Available The values of the solid angles Omega for a range of commonly encountered ligands in organometallic chemistry (phosphines, phosphites, amines, arsines and cyclopentadienyl rings) have been determined. The solid angles were derived from a single...

  17. Laser peripheral iridoplasty for angle-closure.

    Science.gov (United States)

    Ng, Wai Siene; Ang, Ghee Soon; Azuara-Blanco, Augusto

    2012-02-15

    Angle-closure glaucoma is a leading cause of irreversible blindness in the world. Treatment is aimed at opening the anterior chamber angle and lowering the IOP with medical and/or surgical treatment (e.g. trabeculectomy, lens extraction). Laser iridotomy works by eliminating pupillary block and widens the anterior chamber angle in the majority of patients. When laser iridotomy fails to open the anterior chamber angle, laser iridoplasty may be recommended as one of the options in current standard treatment for angle-closure. Laser peripheral iridoplasty works by shrinking and pulling the peripheral iris tissue away from the trabecular meshwork. Laser peripheral iridoplasty can be used for crisis of acute angle-closure and also in non-acute situations.   To assess the effectiveness of laser peripheral iridoplasty in the treatment of narrow angles (i.e. primary angle-closure suspect), primary angle-closure (PAC) or primary angle-closure glaucoma (PACG) in non-acute situations when compared with any other intervention. In this review, angle-closure will refer to patients with narrow angles (PACs), PAC and PACG. We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2011, Issue 12), MEDLINE (January 1950 to January 2012), EMBASE (January 1980 to January 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 5 January 2012. We included only randomised controlled trials (RCTs) in this review. Patients with narrow angles, PAC or PACG were eligible. We excluded studies that included only patients with acute presentations

  18. Limited flip angle MR imaging: Hemorrhagic applications

    International Nuclear Information System (INIS)

    Drayer, B.P.; Rigamonti, D.; Johnson, P.C.; Spetzler, R.F.; Keller, P.J.; Flom, R.A.; Bird, C.R.; Hodak, J.A.

    1987-01-01

    The authors studied 64 patients with hemorrhagic brain lesions, including vascular malformations (n = 29), hemorrhagic infarctions (n = 9), chronic slit hemorrhagic residua of hypertensive hematoma (n = 10), trauma (n = 8), and gliobastoma multiforme (n = 8). With a 1.5-T MR imaging system, 5-mm sections were obtained at a repetition time of 300 msec (or 500), an echo time of 12.3 msec (or 10 and 40), and a flip angle of 60 0 (or 20 0 ). The limited flip angle study was always extremely sensitive for the detection of hemosiderin. With multiple cavernous angiomas, additional small lesions (in five of 18 patients) were detected only with the limited flip angle technique. The hemosiderin-laden macrophage residua of hemorrhagic infarction and hypertensive hematoma were better seen on limited flip angle images than on T2-weighted spin-echo images. The detection of blood on limited flip angle images permitted the grading of glioma as glioblastoma multiforme

  19. Experimental study of crossing angle collision

    International Nuclear Information System (INIS)

    Chen, T.; Rice, D.; Rubin, D.; Sagan, D.; Tigner, M.

    1993-05-01

    The non-linear coupling due to the beam-beam interaction with crossing angle has been studied. The major effect of a small (∼12mrad) crossing angle is to excite 5Q x ±Q s =integer coupling resonance family on large amplitude particles, which results in bad lifetime. On the CESR, a small crossing angle (∼2.4mr) was created at the IP and a reasonable beam-beam tune-shift was achieved. The decay rate of the beam is measured as a function of horizontal tune with and without crossing angle. The theoretical analysis, simulation and experimental measurements have a good agreement. The resonance strength as a function of crossing angle is also measured

  20. Experimental study of crossing angle collision

    International Nuclear Information System (INIS)

    Chen, T.; Rice, D.; Rubin, D.; Sagan, D.; Tigner, M.

    1993-01-01

    The non-linear coupling due to the beam-beam interaction with crossing angle has been studied. The major effect of a small (∼12mrad) crossing angle is to excite 5Q x ±Q s =integer coupling resonance family on large amplitude particles, which results in bad lifetime. On the CESR, a small crossing angle (∼2.4mr) was created at the IP and a reasonable beam-beam tune-shift was achieved. The decay rate of the beam is measured as a function of horizontal tune with and without crossing angle. The theoretical analysis, simulation and experimental measurements have a good agreement. The resonance strength as a function of crossing angle is also measured

  1. Towards a standard design model for quad-rotors: A review of current models, their accuracy and a novel simplified model

    Science.gov (United States)

    Amezquita-Brooks, Luis; Liceaga-Castro, Eduardo; Gonzalez-Sanchez, Mario; Garcia-Salazar, Octavio; Martinez-Vazquez, Daniel

    2017-11-01

    Applications based on quad-rotor-vehicles (QRV) are becoming increasingly wide-spread. Many of these applications require accurate mathematical representations for control design, simulation and estimation. However, there is no consensus on a standardized model for these purposes. In this article a review of the most common elements included in QRV models reported in the literature is presented. This survey shows that some elements are recurrent for typical non-aerobatic QRV applications; in particular, for control design and high-performance simulation. By synthesising the common features of the reviewed models a standard generic model SGM is proposed. The SGM is cast as a typical state-space model without memory-less transformations, a structure which is useful for simulation and controller design. The survey also shows that many QRV applications use simplified representations, which may be considered simplifications of the SGM here proposed. In order to assess the effectiveness of the simplified models, a comprehensive comparison based on digital simulations is presented. With this comparison, it is possible to determine the accuracy of each model under particular operating ranges. Such information is useful for the selection of a model according to a particular application. In addition to the models found in the literature, in this article a novel simplified model is derived. The main characteristics of this model are that its inner dynamics are linear, it has low complexity and it has a high level of accuracy in all the studied operating ranges, a characteristic found only in more complex representations. To complement the article the main elements of the SGM are evaluated with the aid of experimental data and the computational complexity of all surveyed models is briefly analysed. Finally, the article presents a discussion on how the structural characteristics of the models are useful to suggest particular QRV control structures.

  2. Modified angle's classification for primary dentition

    Directory of Open Access Journals (Sweden)

    Kaushik Narendra Chandranee

    2017-01-01

    Full Text Available Aim: This study aims to propose a modification of Angle's classification for primary dentition and to assess its applicability in children from Central India, Nagpur. Methods: Modification in Angle's classification has been proposed for application in primary dentition. Small roman numbers i/ii/iii are used for primary dentition notation to represent Angle's Class I/II/III molar relationships as in permanent dentition, respectively. To assess applicability of modified Angle's classification a cross-sectional preschool 2000 children population from central India; 3–6 years of age residing in Nagpur metropolitan city of Maharashtra state were selected randomly as per the inclusion and exclusion criteria. Results: Majority 93.35% children were found to have bilateral Class i followed by 2.5% bilateral Class ii and 0.2% bilateral half cusp Class iii molar relationships as per the modified Angle's classification for primary dentition. About 3.75% children had various combinations of Class ii relationships and 0.2% children were having Class iii subdivision relationship. Conclusions: Modification of Angle's classification for application in primary dentition has been proposed. A cross-sectional investigation using new classification revealed various 6.25% Class ii and 0.4% Class iii molar relationships cases in preschool children population in a metropolitan city of Nagpur. Application of the modified Angle's classification to other population groups is warranted to validate its routine application in clinical pediatric dentistry.

  3. Patellar angle in Osgood-Schlatter disease.

    Science.gov (United States)

    Sen, R K; Sharma, L R; Thakur, S R; Lakhanpal, V P

    1989-02-01

    A new patellar angle is described in lateral radiographs of the knee joint. One line is drawn along the articular surface of the patella and another from the end of the inferior articular cartilage to the patellar apex. The angle formed by these two lines averaged 33 degrees in 68 knees joints afflicted with Osgood-Schlatter disease and 47 degrees in 71 age-matched controls and 198 adult controls. The small angle in Osgood-Schlatter disease is proposed to be an important factor in the pathogenesis of the traction apophysitis.

  4. Small-angle scattering on soft materials

    International Nuclear Information System (INIS)

    Mortensen, K.

    1994-01-01

    Small angle x-ray and neutron scattering provides tools for investigation of structures on the length scale 10 to 1000 A. This is the length scale which is relevant for many topics within soft materials, like biological macromolecules, polymers, colloids, etc. The very large difference between the scattering amplitude of neutrons by regular hydrogen and deuterium makes neutron scattering a very important technique within soft condensed matter. The basic theory for small angle scattering is reviewed. Experimental results obtained by small angle scattering are shown, with emphasis on soft materials. (author). 33 refs, 6 figs, 1 tab

  5. Computing angle of arrival of radio signals

    Science.gov (United States)

    Borchardt, John J.; Steele, David K.

    2017-11-07

    Various technologies pertaining to computing angle of arrival of radio signals are described. A system that is configured for computing the angle of arrival of a radio signal includes a cylindrical sheath wrapped around a cylindrical object, where the cylindrical sheath acts as a ground plane. The system further includes a plurality of antennas that are positioned about an exterior surface of the cylindrical sheath, and receivers respectively coupled to the antennas. The receivers output measurements pertaining to the radio signal. A processing circuit receives the measurements and computes the angle of arrival of the radio signal based upon the measurements.

  6. Angles-Only Navigation System for Nanosatellites

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposed work is to develop and implement an angles-only relative navigation system on hardware suitable for deployment on nanosatellites or...

  7. Directional Wide-Angle Range Finder (DWARF)

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation, the Directional Wide-Angle Range Finder (DWARF) is the creation of a laser range-finder with a wide field-of-view (FOV) and a directional...

  8. Low angle X-ray scattering

    International Nuclear Information System (INIS)

    Torrianni, I.L.

    1983-01-01

    The theoretical and experimental problems appearing in diffraction experiments at very low angles by several kinds of materials are discussed. The importance of synchrotron radiation in such problems is shown. (L.C.) [pt

  9. Prompt angle measurements with large aperture scintillators

    International Nuclear Information System (INIS)

    Schneid, E.J.

    1976-01-01

    A technique is described for the measurement of particle trajectory angle through a pair of scintillator tiles. Signal processing provides an analog signal proportional to the tangent of the angle between the particle trajectory and the axis normal to the pair of tiles. This signal is readily available for use in fast decision logic if required: i.e., sorting energy loss signals from the tiles according to geometrical factors or restricting the events to be analyzed on the basis of incident direction

  10. Small-angle neutron-scattering experiments

    International Nuclear Information System (INIS)

    Hardy, A.D.; Thomas, M.W.; Rouse, K.D.

    1981-04-01

    A brief introduction to the technique of small-angle neutron scattering is given. The layout and operation of the small-angle scattering spectrometer, mounted on the AERE PLUTO reactor, is also described. Results obtained using the spectrometer are presented for three materials (doped uranium dioxide, Magnox cladding and nitrided steel) of interest to Springfields Nuclear Power Development Laboratories. The results obtained are discussed in relation to other known data for these materials. (author)

  11. Axial vector mass spectrum and mixing angles

    International Nuclear Information System (INIS)

    Caffarelli, R.V.; Kang, K.

    1976-01-01

    Spectral sum rules of the axial-vector current and axial-vector current-pseudoscalar field are used to study the axial-vector mass spectrum and mixing angles, as well as the decay constants and mixing angles of the pseudoscalar mesons. In general, the result is quite persuasive for the existence of the Jsup(PC) = 1 ++ multiplet in which one has a canonical D-E mixing. (Auth.)

  12. Sharper angle, higher risk? The effect of cutting angle on knee mechanics in invasion sport athletes.

    Science.gov (United States)

    Schreurs, Mervin J; Benjaminse, Anne; Lemmink, Koen A P M

    2017-10-03

    Cutting is an important skill in team-sports, but unfortunately is also related to non-contact ACL injuries. The purpose was to examine knee kinetics and kinematics at different cutting angles. 13 males and 16 females performed cuts at different angles (45°, 90°, 135° and 180°) at maximum speed. 3D kinematics and kinetics were collected. To determine differences across cutting angles (45°, 90°, 135° and 180°) and sex (female, male), a 4×2 repeated measures ANOVA was conducted followed by post hoc comparisons (Bonferroni) with alpha level set at α≤0.05a priori. At all cutting angles, males showed greater knee flexion angles than females (pknee flexion -42.53°±8.95°, females decreased their knee flexion angle from -40.6°±7.2° when cutting at 45° to -36.81°±9.10° when cutting at 90°, 135° and 180° (pKnee flexion moment decreased for both sexes when cutting towards sharper angles (pknee valgus moments than females. For both sexes, knee valgus moment increased towards the sharper cutting angles and then stabilized compared to the 45° cutting angle (pknee kinematics and kinetics. Sharper cutting angles place the knee more at risk. However, females and males handle this differently, which has implications for injury prevention. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Solar cell angle of incidence corrections

    Science.gov (United States)

    Burger, Dale R.; Mueller, Robert L.

    1995-01-01

    Literature on solar array angle of incidence corrections was found to be sparse and contained no tabular data for support. This lack along with recent data on 27 GaAs/Ge 4 cm by 4 cm cells initiated the analysis presented in this paper. The literature cites seven possible contributors to angle of incidence effects: cosine, optical front surface, edge, shadowing, UV degradation, particulate soiling, and background color. Only the first three are covered in this paper due to lack of sufficient data. The cosine correction is commonly used but is not sufficient when the incident angle is large. Fresnel reflection calculations require knowledge of the index of refraction of the coverglass front surface. The absolute index of refraction for the coverglass front surface was not known nor was it measured due to lack of funds. However, a value for the index of refraction was obtained by examining how the prediction errors varied with different assumed indices and selecting the best fit to the set of measured values. Corrections using front surface Fresnel reflection along with the cosine correction give very good predictive results when compared to measured data, except there is a definite trend away from predicted values at the larger incident angles. This trend could be related to edge effects and is illustrated by a use of a box plot of the errors and by plotting the deviation of the mean against incidence angle. The trend is for larger deviations at larger incidence angles and there may be a fourth order effect involved in the trend. A chi-squared test was used to determine if the measurement errors were normally distributed. At 10 degrees the chi-squared test failed, probably due to the very small numbers involved or a bias from the measurement procedure. All other angles showed a good fit to the normal distribution with increasing goodness-of-fit as the angles increased which reinforces the very small numbers hypothesis. The contributed data only went to 65 degrees

  14. Comparative biometric study between plateau iris configuration and primary open angle glaucoma with narrow angle.

    Science.gov (United States)

    Diniz Filho, Alberto; Cronemberger, Sebastião; Mérula, Rafael Vidal; Calixto, Nassim

    2009-01-01

    To investigate biometrically the differences between plateau iris configuration (PIC) eyes and primary open angle glaucoma with narrow angle eyes. A comparative study involving a case series with 20 eyes of 11 plateau iris configuration patients and 45 eyes of 27 primary open angle glaucoma with narrow angle eyes patients was done. The following measurements were taken: corneal curvature, central corneal thickness, anterior chamber depth, lens thickness (LT), axial length (AL), lens thickness and axial length ratio, lens position (LP) and relative lens position (RLP). The plateau iris configuration eyes presented a higher corneal cuvature value than primary open angle glaucoma with narrow angle eyes eyes but not with clinical and statistical difference (P=0.090). The plateau iris configuration eyes demonstrated a higher central corneal thickness, with statistical significance, when compared to primary open angle glaucoma with narrow angle eyes (P=0.010). Statistical significant difference between plateau iris configuration and primary open angle glaucoma with narrow angle eyes was found in axial length (21.69 +/- 0.98 vs. 22.42 +/- 0.89; P=0.003). No significant difference was found when anterior chamber depth (2.62 +/- 0.23 vs. 2.71 +/- 0.31; P=0.078), LT (4.67 +/- 0.36 vs. 4.69 +/- 0.45; P=0.975), LT/AL (2.16 +/- 0.17 vs. 2.10 +/- 0.21; P=0.569), LP (4.95 +/- 0.25 vs. 5.06 +/- 0.34; P=0.164) and RLP (0.23 +/- 0.01 vs. 0.22 +/- 0.14; P=0.348) were evaluated. The eyes with plateau iris configuration presented statistical significantly shorter axial length and higher central corneal thickness than primary open angle glaucoma with narrow angle eyes.

  15. Fractal approach in petrology: Combining ultra small angle (USANS), and small angle neutron scattering (SANS)

    International Nuclear Information System (INIS)

    Lo Celso, F.; Triolo, R.; Triolo, F.; Triolo, A.; Lin, J.S.; Lucido, G.

    2000-01-01

    Ultra small angle neutron scattering instruments have recently covered the gap between the size resolution available with conventional intermediate angle neutron scattering and small angle neutron scattering instruments on one side and optical microscopy on the other side. Rocks showing fractal behavior in over two decades of momentum transfer and seven orders of magnitude of intensity are examined and fractal parameters are extracted from the combined USANS and SANS curves

  16. Fractal Approach in Petrology: Combining Ultra-Small Angle (USANS) and Small Angle Neutron Scattering (SANS)

    International Nuclear Information System (INIS)

    LoCelso, F.; Triolo, F.; Triolo, A.; Lin, J.S.; Lucido, G.; Triolo, R.

    1999-01-01

    Ultra small angle neutron scattering instruments have recently covered the gap between the size resolution available with conventional intermediate angle neutron scattering and small angle neutron scattering instruments on one side and optical microscopy on the other side. Rocks showing fractal behavior in over two decades of momentum transfer and seven orders of magnitude of intensity are examined and fractal parameters are extracted from the combined USANS and SANS curves

  17. Graphene spin valve: An angle sensor

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Muhammad Zahir, E-mail: zahir.upc@gmail.com [Faculty of Engineering Sciences, GIK Institute of Engineering Sciences and Technology, Topi 23640, Khyber Pakhtunkhwa (Pakistan); Hussain, Ghulam [Faculty of Engineering Sciences, GIK Institute of Engineering Sciences and Technology, Topi 23640, Khyber Pakhtunkhwa (Pakistan); Siddique, Salma [Department of Bioscience & Biotechnology, Sejong University, Seoul 143-747 (Korea, Republic of); Iqbal, Muhammad Waqas [Department of Physics, Riphah Institute of Computing and Applied Sciences (RICAS), Riphah International University, Lahore (Pakistan)

    2017-06-15

    Graphene spin valves can be optimized for various spintronic applications by tuning the associated experimental parameters. In this work, we report the angle dependent magnetoresistance (MR) in graphene spin valve for different orientations of applied magnetic field (B). The switching points of spin valve signals show a clear shift towards higher B for each increasing angle of the applied field, thus sensing the response for respective orientation of the magnetic field. The angular variation of B shifts the switching points from ±95 G to ±925 G as the angle is varied from 0° to 90° at 300 K. The observed shifts in switching points become more pronounced (±165 G to ±1450 G) at 4.2 K for similar orientation. A monotonic increase in MR ratio is observed as the angle of magnetic field is varied in the vertical direction at 300 K and 4.2 K temperatures. This variation of B (from 0° to 90°) increases the magnitude of MR ratio from ∼0.08% to ∼0.14% at 300 K, while at 4.2 K it progresses to ∼0.39% from ∼0.14%. The sensitivity related to angular variation of such spin valve structure can be employed for angle sensing applications.

  18. A Viewpoint on the Quantity "Plane Angle"

    Science.gov (United States)

    Eder, W. E.

    1982-01-01

    Properties of the quantity "plane angle" are explored under the hypothesis that it is a dimensional quantity. The exploration proceeds especially with respect to the physical concept, its mathematical treatment, vector concepts, measurement theory, units of related quantities, engineering pragmatism, and SI. An attempt is made to bring these different relations into a rational, logical and consistent framework, and thus to justify the hypothesis. Various types of vectorial quantities are recognized, and their properties described with an outline of the necessary algebraic manipulations. The concept of plane angle is amplified, and its interdependence with the circular arc is explored. The resulting units of plane angle form a class of similar scales of measurement. Consequences of the confirmed hypothesis are developed for mathematical expressions involving trigonometric functions, rotational volumes and areas, mathematical limits, differentiation and series expansion. Consequences for mechanical rotational quantities are developed, with proposals for revisions to a number of expressions for derived units within SI. A revised definition for the quantity "plane angle" is stated to take account of the developed insights. There is a clear need to reconsider the status of plane angle and some other quantities within the international framework of SI.

  19. PRIMARY OPEN ANGLE GLAUCOMA IN THYROID DISORDER

    Directory of Open Access Journals (Sweden)

    Pragati Garg

    2016-07-01

    Full Text Available PURPOSE To assess the association of thyroid profile with open angle glaucoma. DESIGN Cross-sectional observational study. MATERIAL AND METHOD 128 cases of diagnosed thyroid disorder were enrolled. 5 cases dropped out. Ocular examination included applanation tonometry, stereoscopic optic disc photography, and automated perimetry. Correlative association of thyroid disorder and open angle glaucoma was assessed. RESULTS Of 123 patients of thyroid disorder, 87.8% had hypothyroidism and remaining 12.2% had hyperthyroidism. 15.74% of hypothyroidism and 20% of hyperthyroidism patients had open angle glaucoma, which was statistically significant (Pearson chi-square: Value=6.548, df=2, p=0.040. On multivariate analysis with other risk factors like female sex, family history of glaucoma, myopia, hypertension, and diabetes; it was found that hypothyroidism is an independent risk factor for open angle glaucoma. CONCLUSION All patients having thyroid disorder should be investigated for early diagnosis of open angle glaucoma so that if need be antiglaucoma treatment is started at the earliest and the eye maybe saved from any further deterioration.

  20. Angle-averaged Compton cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Nickel, G.H.

    1983-01-01

    The scattering of a photon by an individual free electron is characterized by six quantities: ..cap alpha.. = initial photon energy in units of m/sub 0/c/sup 2/; ..cap alpha../sub s/ = scattered photon energy in units of m/sub 0/c/sup 2/; ..beta.. = initial electron velocity in units of c; phi = angle between photon direction and electron direction in the laboratory frame (LF); theta = polar angle change due to Compton scattering, measured in the electron rest frame (ERF); and tau = azimuthal angle change in the ERF. We present an analytic expression for the average of the Compton cross section over phi, theta, and tau. The lowest order approximation to this equation is reasonably accurate for photons and electrons with energies of many keV.

  1. On the dip angle of subducting plates

    Science.gov (United States)

    Hsui, Albert T.; Tang, Xiao-Ming; Toksoz, M. Nafi

    1990-01-01

    A new approximate analytic model is developed for the thermal structure of a subducting plate with a finite length. This model provides the capability of easily examining the thermal and mechanical structure of a subducting plate with different lengths and at different angles. Also, the torque balance of a descending plate can be examined, and effects such as the leading edge effect, the adiabatic compression effect, and the phase change effect can be incorporated. A comparison with observed data indicates that short slabs are likely under torque equilibrium at present, while long slabs are probably dominated by their gravitational torques such that their dip angles are transient, moving toward a steeper dip angle similar to that of the Mariana slab.

  2. Angle-averaged Compton cross sections

    International Nuclear Information System (INIS)

    Nickel, G.H.

    1983-01-01

    The scattering of a photon by an individual free electron is characterized by six quantities: α = initial photon energy in units of m 0 c 2 ; α/sub s/ = scattered photon energy in units of m 0 c 2 ; β = initial electron velocity in units of c; phi = angle between photon direction and electron direction in the laboratory frame (LF); theta = polar angle change due to Compton scattering, measured in the electron rest frame (ERF); and tau = azimuthal angle change in the ERF. We present an analytic expression for the average of the Compton cross section over phi, theta, and tau. The lowest order approximation to this equation is reasonably accurate for photons and electrons with energies of many keV

  3. Precision measurements of the CKM angle gamma

    CERN Multimedia

    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.

  4. Flocking and invariance of velocity angles.

    Science.gov (United States)

    Liu, Le; Huang, Lihong; Wu, Jianhong

    2016-04-01

    Motsch and Tadmor considered an extended Cucker-Smale model to investigate the flocking behavior of self-organized systems of interacting species. In this extended model, a cone of the vision was introduced so that outside the cone the influence of one agent on the other is lost and hence the corresponding influence function takes the value zero. This creates a problem to apply the Motsch-Tadmor and Cucker-Smale method to prove the flocking property of the system. Here, we examine the variation of the velocity angles between two arbitrary agents, and obtain a monotonicity property for the maximum cone of velocity angles. This monotonicity permits us to utilize existing arguments to show the flocking property of the system under consideration, when the initial velocity angles satisfy some minor technical constraints.

  5. A heterodyne interferometer for angle metrology

    International Nuclear Information System (INIS)

    Hahn, Inseob; Weilert, M.; Wang, X.; Goullioud, R.

    2010-01-01

    We have developed a compact, high-resolution, angle measurement instrument based on a heterodyne interferometer. Common-path heterodyne interferometer metrology is used to measure displacements of a reflective target surface. In the interferometer set up, an optical mask is used to sample the laser beam reflecting back from four areas on a target surface. From the relative displacement measurements of the target surface areas, we can simultaneously determine angular rotations around two orthogonal axes in a plane perpendicular to the measurement beam propagation direction. The device is used in a testbed for a tracking telescope system where pitch and yaw angle measurements of a flat mirror are performed. Angle noise measurement of the device shows 0.1 nrad/√(Hz) at 1 Hz, at a working distance of 1 m. The operation range and nonlinearity of the device when used with a flat mirror is approximately ±0.15 mrad, and 3 μrad rms, respectively.

  6. Positron Emission Mammography with Multiple Angle Acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Mark F. Smith; Stan Majewski; Raymond R. Raylman

    2002-11-01

    Positron emission mammography (PEM) of F-18 fluorodeoxyglucose (FDG) uptake in breast tumors with dedicated detectors typically has been accomplished with two planar detectors in a fixed position with the breast under compression. The potential use of PEM imaging at two detector positions to guide stereotactic breast biopsy has motivated us to use PEM coincidence data acquired at two or more detector positions together in a single image reconstruction. Multiple angle PEM acquisition and iterative image reconstruction were investigated using point source and compressed breast phantom acquisitions with 5, 9, 12 and 15 mm diameter spheres and a simulated tumor:background activity concentration ratio of 6:1. Image reconstruction was performed with an iterative MLEM algorithm that used coincidence events between any two detector pixels on opposed detector heads at each detector position. This present study compared two acquisition protocols: 2 angle acquisition with detector angular positions of -15 and +15 degrees and 11 angle acquisition with detector positions spaced at 3 degree increments over the range -15 to +15 degrees. Three- dimensional image resolution was assessed for the point source acquisitions, and contrast and signal-to-noise metrics were evaluated for the compressed breast phantom with different simulated tumor sizes. Radial and tangential resolutions were similar for the two protocols, while normal resolution was better for the 2 angle acquisition. Analysis is complicated by the asymmetric point spread functions. Signal- to-noise vs. contrast tradeoffs were better for 11 angle acquisition for the smallest visible 9 mm sphere, while tradeoff results were mixed for the larger and more easily visible 12 mm and 15 mm diameter spheres. Additional study is needed to better understand the performance of limited angle tomography for PEM. PEM tomography experiments with complete angular sampling are planned.

  7. Positron Emission Mammography with Multiple Angle Acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Mark F. Smith; Stan Majewski; Raymond R. Raylman

    2002-11-01

    Positron emission mammography (PEM) of F-18 fluorodeoxyglucose (FbG) uptake in breast tumors with dedicated detectors typically has been accomplished with two planar detectors in a fixed position with the breast under compression. The potential use of PEM imaging at two detector positions to guide stereotactic breast biopsy has motivated us to use PEM coincidence data acquired at two or more detector positions together in a single image reconstruction. Multiple angle PEM acquisition and iterative image reconstruction were investigated using point source and compressed breast phantom acquisitions with 5, 9, 12 and 15 mm diameter spheres and a simulated tumor:background activity concentration ratio of 6:1. Image reconstruction was performed with an iterative MLEM algorithm that used coincidence events between any two detector pixels on opposed detector heads at each detector position. This present study compared two acquisition protocols: 2 angle acquisition with detector angular positions of -15 and +15 degrees and 11 angle acquisition with detector positions spaced at 3 degree increments over the range -15 to +15 degrees. Three-dimensional image resolution was assessed for the point source acquisitions, and contrast and signal-to-noise metrics were evaluated for the compressed breast phantom with different simulated tumor sizes. Radial and tangential resolutions were similar for the two protocols, while normal resolution was better for the 2 angle acquisition. Analysis is complicated by the asymmetric point spread functions. Signal- to-noise vs. contrast tradeoffs were better for 11 angle acquisition for the smallest visible 9 mm sphere, while tradeoff results were mixed for the larger and more easily visible 12 mm and 15 mm diameter spheres. Additional study is needed to better understand the performance of limited angle tomography for PEM. PEM tomography experiments with complete angular sampling are planned.

  8. Angles between Curves in Metric Measure Spaces

    Directory of Open Access Journals (Sweden)

    Han Bang-Xian

    2017-09-01

    Full Text Available The goal of the paper is to study the angle between two curves in the framework of metric (and metric measure spaces. More precisely, we give a new notion of angle between two curves in a metric space. Such a notion has a natural interplay with optimal transportation and is particularly well suited for metric measure spaces satisfying the curvature-dimension condition. Indeed one of the main results is the validity of the cosine formula on RCD*(K, N metric measure spaces. As a consequence, the new introduced notions are compatible with the corresponding classical ones for Riemannian manifolds, Ricci limit spaces and Alexandrov spaces.

  9. Small angle neutron scattering and small angle X-ray scattering ...

    Indian Academy of Sciences (India)

    Abstract. The morphology of carbon nanofoam samples comprising platinum nanopar- ticles 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 ...

  10. Using Digital Technology to See Angles from Different Angles. Part 2: Openings and Turns

    Science.gov (United States)

    Host, Erin; Baynham, Emily; McMaster, Heather

    2015-01-01

    Ever wondered how to use technology to teach angles? This article follows on from an earlier article published last year, providing a range of ideas for integrating technology and concrete materials with the teaching of angle concepts. The authors also provide a comprehensive list of free online games and learning objects that can be used to teach…

  11. Long-term outcomes after acute primary angle closure of Caucasian chronic angle closure glaucoma patients.

    Science.gov (United States)

    Fea, Antonio Maria; Dallorto, Laura; Lavia, Carlo; Pignata, Giulia; Rolle, Teresa; Aung, Tin

    2017-07-19

    There is a lack of information about long-term results of chronic angle closure glaucoma following an acute primary angle closure attack in Caucasian patients. The aim of the study was to report morphological and functional long-term data of chronic angle closure eyes following a monolateral primary angle closure attack and to provide a comparison with their fellow eyes. Observational retrospective case series. Fifty-seven consecutive patients (114 eyes) underwent long-term follow-up analysis. Patients underwent ophthalmic assessment more than 5 years since the angle closure attack. Intraocular pressure, best-corrected visual acuity, angle assessment, vertical C/D ratio and standard automated perimetry were the main outcome measures. Comparisons were made between angle closure attack eyes and fellow eyes and between phakic and pseudophakic eyes. Mean follow-up time was 5.86 ± 1.19 years. A significant greater damage in the angle closure eyes compared with fellow eyes in both structural (mean C/D 0.61 ± 0.16; P APAC attack to prevent potential glaucoma damage in both APAC and fellow eye. © 2017 The Authors Clinical & Experimental Ophthalmology published by John Wiley & Sons Australia, Ltd on behalf of Royal Australian and New Zealand College of Ophthalmologists.

  12. Small angle neutron scattering and small angle X-ray scattering ...

    Indian Academy of Sciences (India)

    Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India. *Corresponding author ... ticles dispersed in the matrix was characterized by small angle neutron scattering (SANS) and small angle X-ray ... for scattering from rough pore–mass interfaces, α > 3 and the (surface) fractal dimension Ds = 6 ...

  13. Sharper angle, higher risk? The effect of cutting angle on knee mechanics in invasion sport athletes

    NARCIS (Netherlands)

    Schreurs, Mervin J.; Benjaminse, Anne; Lemmink, Koen A. P. M.

    2017-01-01

    Introduction: Cutting is an important skill in team-sports, but unfortunately is also related to non-contact ACL injuries. The purpose was to examine knee kinetics and kinematics at different cutting angles. Material and methods: 13 males and 16 females performed cuts at different angles (45°, 90°,

  14. Small angle neutron scattering and small angle X-ray scattering ...

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... Small angle neutron scattering and small angle X-ray scattering studies of platinum-loaded carbon foams. P U Sastry V K Aswal A G Wagh ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November ...

  15. Angle at the Medial Border: The Spinovertebra Angle and Its Significance

    Directory of Open Access Journals (Sweden)

    G. S. Oladipo

    2015-01-01

    Full Text Available Background. The evolution from quadrupedalism to bipedalism has adjusted the balance of the upper limb to extensive movement at the shoulder. The scapular angles provide the point of attachment and control to various muscles and have been associated with the different movements of the shoulder girdle and joint. This has made the morphometric and anthropometric study of scapula a subject of extensive investigation. Aim. In the present study, the angle at the medial border was measured in the South-Southern Nigerian population and an anatomical name was ascribed to the angle. Method. The study was conducted on 173 scapulae (75 right and 98 left obtained from various Anatomy Department of South-Sothern Nigerian Universities. The angle at medial border was obtained by pinning the edge of the superior and inferior angles, the lined traced out, and the angle measured using a protractor. SPSS version 20 was used to analyse the data. t-test was used to determine mean angular difference in the sides. Result. The mean ± SD of the medial angle was observed to be 136.88 ± 7.70° (R = 138.13 ± 7.06° : L = 135.92 ± 8.05°. Statistical analysis using the Z-test for mean difference showed the medial angle was found to be higher in the right side of the scapula (mean difference of 2.214 ± 1.152°, but the observed difference was not statistically significant (P > 0.05. The above findings have adjusted the scapula from three to four angles (lateral, superior, inferior, and medial formed from four borders (lateral, superior, inferior, and superomedial and inferomedial. The medial angle because of its anatomical location was named “spinovertebral” angle, owing to its position at the scapulae spine, and located in medial proximity to the vertebra column. Conclusion. The medial angle (now referred to as the spinovertebral angle of the right side of the scapula is wider than the left. The representation of the spinovertebral angle is very important, as

  16. CKM matrix exponential parametrization and Euler angles

    International Nuclear Information System (INIS)

    Dattoli, G.; Sabia, E.; Torre, A.

    1997-01-01

    They show that the exponential parametrization of the CKM matrix allows to establish exact relations between the Euler weak rotation angles and the entries of the CKM generating matrix, which has already been shown to include the hierarchy features of the Wolfenstein parametrization. The analysis includes CP-violating effects and its usefulness to treat the experimental data is also proved

  17. Gaugings at angles from orientifold reductions

    NARCIS (Netherlands)

    Roest, D.

    2009-01-01

    We consider orientifold reductions to N = 4 gauged supergravity in four dimensions. A special feature of this theory is that different factors of the gauge group can have relative angles with respect to the electro-magnetic SL(2) symmetry. These are crucial for moduli stabilization and de Sitter

  18. Experimental technique of small angle neutron scattering

    International Nuclear Information System (INIS)

    Xia Qingzhong; Chen Bo

    2006-03-01

    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)

  19. The resection angle in apical surgery

    DEFF Research Database (Denmark)

    von Arx, Thomas; Janner, Simone F M; Jensen, Simon S

    2016-01-01

    OBJECTIVES: The primary objective of the present radiographic study was to analyse the resection angle in apical surgery and its correlation with treatment outcome, type of treated tooth, surgical depth and level of root-end filling. MATERIALS AND METHODS: In the context of a prospective clinical...

  20. A thin film magnetoresistive angle detector

    NARCIS (Netherlands)

    Eijkel, C.J.M.; Wieberdink, Johan W.; Fluitman, J.H.J.; Popma, T.J.A.; Groot, Peter; Leeuwis, Henk

    1990-01-01

    An overview is given of the results of our research on a contactless angle detector based on the anisotropic magnetoresistance effect (AMR effect) in a permalloy thin film. The results of high-temperature annealing treatment of the pemalloy film are discussed. Such a treatment suppresses the effects

  1. A small-angle neutron scattering study

    Indian Academy of Sciences (India)

    400Da [9]. Low-angle X-ray scattering [10] and neutron scattering [11] also in- dicated serum albumin to be a prolate ellipsoid. However, studies using 1H NMR indicated that a prolate structure was unlikely; rather a heart-shaped structure was proposed [12]. The shape of albumin reveals a heart-shaped molecule that can.

  2. Solid angle subtended by two circular discs

    International Nuclear Information System (INIS)

    Gilly, Louis.

    1978-09-01

    Methods of calculation of solid angles, subtended by two circular discs are analysed. Calculus are methodically classified as follow: series development Legendre polynomes, defined integral, elliptic integrals, Bessel integrals, multiple integrals, Monte Carlo method, electrostatic analogy. Applications in Nuclear Physics are added as examples. List of numeric tables completes bibliography [fr

  3. Small Angle Light Scattering by Biological Objects

    International Nuclear Information System (INIS)

    Berdzenishvili, L.; Melikishvili, Z.

    2005-01-01

    In this paper the small angle laser radiation scattering by the particles of different shape and size is analyzed. Experimental results and theoretical calculations show that after ejection from bacteriophage DNA forms the scattering medium consisted of quasi-spherical elements with radius of R⁓10λ 0 . (author)

  4. Direct angle resolved photoemission spectroscopy and ...

    Indian Academy of Sciences (India)

    Since 1997 we systematically perform direct angle resolved photoemission spectroscopy (ARPES) on in-situ grown thin (< 30 nm) cuprate films. Specifically, we probe low-energy electronic structure and properties of high-c superconductors (HTSC) under different degrees of epitaxial (compressive vs. tensile) strain.

  5. Right-Angle Mechanized Electrical Connector

    Science.gov (United States)

    Collins, Clint A.; Blackler, David T.

    1996-01-01

    Right-angle electrical connector embedded in mechanism accommodates some initial misalignment and aligns itself. Connection and disconnection effected with relatively small forces and torques and simple movements. Actuated by one gloved hand or by robotic manipulator. Useful in underwater, nuclear, hot, cold, or toxic environments in which connections made or broken by heavily clothed technicians or by robots.

  6. A small angle neutron scattering study

    Indian Academy of Sciences (India)

    Nanocrystalline nickel oxide powders were calcined at 300, 600 and 900°C and pore structure evolution was followed by small angle neutron scattering (SANS). Pore size distributions at two widely separated size ranges have been revealed. Shrinkage of larger-sized pore with reduction in polydispersity has been observed ...

  7. SANS-1: Small angle neutron scattering

    Directory of Open Access Journals (Sweden)

    André Heinemann

    2015-08-01

    Full Text Available The new small angle scattering instrument SANS-1, jointly operated by the Technische Universität München and GEMS, Helmholtz-Zentrum Geesthacht, has completed commissioning and is in regular user service (Gilles et al., 2006. SANS-1 is located at the end of neutron guide NL4a in the Neutron Guide Hall West.

  8. SANS-1: Small angle neutron scattering

    OpenAIRE

    Heinemann, André; Mühlbauer, Sebastian

    2015-01-01

    The new small angle scattering instrument SANS-1, jointly operated by the Technische Universität München and GEMS, Helmholtz-Zentrum Geesthacht, has completed commissioning and is in regular user service (Gilles et al., 2006). SANS-1 is located at the end of neutron guide NL4a in the Neutron Guide Hall West.

  9. Camber Angle Inspection for Vehicle Wheel Alignments.

    Science.gov (United States)

    Young, Jieh-Shian; Hsu, Hong-Yi; Chuang, Chih-Yuan

    2017-02-03

    This paper introduces an alternative approach to the camber angle measurement for vehicle wheel alignment. Instead of current commercial approaches that apply computation vision techniques, this study aims at realizing a micro-control-unit (MCU)-based camber inspection system with a 3-axis accelerometer. We analyze the precision of the inspection system for the axis misalignments of the accelerometer. The results show that the axes of the accelerometer can be aligned to the axes of the camber inspection system imperfectly. The calibrations that can amend these axis misalignments between the camber inspection system and the accelerometer are also originally proposed since misalignments will usually happen in fabrications of the inspection systems. During camber angle measurements, the x -axis or z -axis of the camber inspection system and the wheel need not be perfectly aligned in the proposed approach. We accomplished two typical authentic camber angle measurements. The results show that the proposed approach is applicable with a precision of ± 0.015 ∘ and therefore facilitates the camber measurement process without downgrading the precision by employing an appropriate 3-axis accelerometer. In addition, the measured results of camber angles can be transmitted via the medium such as RS232, Bluetooth, and Wi-Fi.

  10. Camber Angle Inspection for Vehicle Wheel Alignments

    Directory of Open Access Journals (Sweden)

    Jieh-Shian Young

    2017-02-01

    Full Text Available This paper introduces an alternative approach to the camber angle measurement for vehicle wheel alignment. Instead of current commercial approaches that apply computation vision techniques, this study aims at realizing a micro-control-unit (MCU-based camber inspection system with a 3-axis accelerometer. We analyze the precision of the inspection system for the axis misalignments of the accelerometer. The results show that the axes of the accelerometer can be aligned to the axes of the camber inspection system imperfectly. The calibrations that can amend these axis misalignments between the camber inspection system and the accelerometer are also originally proposed since misalignments will usually happen in fabrications of the inspection systems. During camber angle measurements, the x-axis or z-axis of the camber inspection system and the wheel need not be perfectly aligned in the proposed approach. We accomplished two typical authentic camber angle measurements. The results show that the proposed approach is applicable with a precision of ± 0.015 ∘ and therefore facilitates the camber measurement process without downgrading the precision by employing an appropriate 3-axis accelerometer. In addition, the measured results of camber angles can be transmitted via the medium such as RS232, Bluetooth, and Wi-Fi.

  11. A small-angle neutron scattering investigation

    Indian Academy of Sciences (India)

    Hence, the steel is used in aircraft, nuclear reactor, petrochemical plants and many other industries. However, presence of carbide formers such as Mo and Cr war- rants the possibility of carbide precipitates in the structure and in turn affects the mechanical properties. Small-angle neutron scattering (SANS) is an important ...

  12. Contact angle measurement with a smartphone

    Science.gov (United States)

    Chen, H.; Muros-Cobos, Jesus L.; Amirfazli, A.

    2018-03-01

    In this study, a smartphone-based contact angle measurement instrument was developed. Compared with the traditional measurement instruments, this instrument has the advantage of simplicity, compact size, and portability. An automatic contact point detection algorithm was developed to allow the instrument to correctly detect the drop contact points. Two different contact angle calculation methods, Young-Laplace and polynomial fitting methods, were implemented in this instrument. The performance of this instrument was tested first with ideal synthetic drop profiles. It was shown that the accuracy of the new system with ideal synthetic drop profiles can reach 0.01% with both Young-Laplace and polynomial fitting methods. Conducting experiments to measure both static and dynamic (advancing and receding) contact angles with the developed instrument, we found that the smartphone-based instrument can provide accurate and practical measurement results as the traditional commercial instruments. The successful demonstration of use of a smartphone (mobile phone) to conduct contact angle measurement is a significant advancement in the field as it breaks the dominate mold of use of a computer and a bench bound setup for such systems since their appearance in 1980s.

  13. Measurement of the angle alpha at BABAR

    International Nuclear Information System (INIS)

    Perez, A.

    2009-01-01

    The authors present recent measurements of the CKM angle α using data collected by the BABAR detector at the PEP-II asymmetric-energy e + e - collider at the SLAC National Accelerator Laboratory, operating at the Υ(4S) resonance. They present constraints on α from B → ππ, B → ρρ and B → ρπ decays.

  14. Evaluation of protein dihedral angle prediction methods.

    Directory of Open Access Journals (Sweden)

    Harinder Singh

    Full Text Available Tertiary structure prediction of a protein from its amino acid sequence is one of the major challenges in the field of bioinformatics. Hierarchical approach is one of the persuasive techniques used for predicting protein tertiary structure, especially in the absence of homologous protein structures. In hierarchical approach, intermediate states are predicted like secondary structure, dihedral angles, Cα-Cα distance bounds, etc. These intermediate states are used to restraint the protein backbone and assist its correct folding. In the recent years, several methods have been developed for predicting dihedral angles of a protein, but it is difficult to conclude which method is better than others. In this study, we benchmarked the performance of dihedral prediction methods ANGLOR and SPINE X on various datasets, including independent datasets. TANGLE dihedral prediction method was not benchmarked (due to unavailability of its standalone and was compared with SPINE X and ANGLOR on only ANGLOR dataset on which TANGLE has reported its results. It was observed that SPINE X performed better than ANGLOR and TANGLE, especially in case of prediction of dihedral angles of glycine and proline residues. The analysis suggested that angle shifting was the foremost reason of better performance of SPINE X. We further evaluated the performance of the methods on independent ccPDB30 dataset and observed that SPINE X performed better than ANGLOR.

  15. Measurement of critical angle in SSTDs

    International Nuclear Information System (INIS)

    Marques, A.; Serra, D.A.B.

    1984-01-01

    A method of measurement of critical angles of etching is described, relying upon the distortion caused in the shape of the distribution in the number of etched tracks of ions emitted from a 'point-like' source. The method is applied to quartz and mica samples. (author)

  16. Contact angle measurement with a smartphone.

    Science.gov (United States)

    Chen, H; Muros-Cobos, Jesus L; Amirfazli, A

    2018-03-01

    In this study, a smartphone-based contact angle measurement instrument was developed. Compared with the traditional measurement instruments, this instrument has the advantage of simplicity, compact size, and portability. An automatic contact point detection algorithm was developed to allow the instrument to correctly detect the drop contact points. Two different contact angle calculation methods, Young-Laplace and polynomial fitting methods, were implemented in this instrument. The performance of this instrument was tested first with ideal synthetic drop profiles. It was shown that the accuracy of the new system with ideal synthetic drop profiles can reach 0.01% with both Young-Laplace and polynomial fitting methods. Conducting experiments to measure both static and dynamic (advancing and receding) contact angles with the developed instrument, we found that the smartphone-based instrument can provide accurate and practical measurement results as the traditional commercial instruments. The successful demonstration of use of a smartphone (mobile phone) to conduct contact angle measurement is a significant advancement in the field as it breaks the dominate mold of use of a computer and a bench bound setup for such systems since their appearance in 1980s.

  17. Intra- and Interobserver Reliability of the Cobb Angle-Vertebral Rotation Angle-Spinous Process Angle for Adolescent Idiopathic Scoliosis.

    Science.gov (United States)

    Chan, Amanda C Y; Morrison, Devlin G; Nguyen, Duc V; Hill, Douglas L; Parent, Eric; Lou, Edmond H M

    2014-05-01

    A reliability analysis of Cobb angle, vertebral rotation (VR), and spinous process angle (SPA) measurements in adolescent idiopathic scoliosis. To determine the intra- and interobserver reliability of semi-automated digital radiograph measurements. Cobb angle measurements on posteroanterior radiographs are commonly used to determine the severity of scoliosis. Vertebral rotation helps assess scoliosis 3-dimensionally and has a role in predicting curve progression. Recent studies have shown that the spinous process angle is a useful parameter in assessing scoliosis when using ultrasound imaging. Because the reliability of SPA measurements on radiographs has yet to be determined, it is important to compare the reliability of these 3 parameters (Cobb angle, VR, and SPA) using a computer assisted semi-automated method. Sixty posteroanterior radiographs of patients with adolescent idiopathic scoliosis were obtained and measured twice by 3 observers who were blinded to their previous measurements, using an in-house developed program. Measurements were obtained using a semi-automated method to minimize variability resulting from observer reliability. The intra- and interobserver reliabilities were analyzed using intra-class correlation coefficients (ICCs) as well as Bland-Altman's bias and limits of agreement. Over 350 (intra) and 90 (inter) sets of curves with an average Cobb angle of 26° ± 9° (range, 10° to 44°) were compared for each parameter. Intra-observer reliabilities for each parameter were excellent (ICC [2,1] , .82; 1.00), with mean absolute differences under 3° between most measurements. Interobserver reliability (ICC [2,1] , .72; .95) was mostly good to excellent, with mean absolute differences ranging from 2.0° to 5.6°. Both the intra- and interobserver assessment of the Cobb, VR, and SPA from the semi-automated measurements had clinically acceptable reliability ranges and may be considered for clinical implementation. Additional studies will be

  18. Anatomic predictors for anterior chamber angle opening after laser peripheral iridotomy in narrow angle eyes.

    Science.gov (United States)

    Huang, Guofu; Gonzalez, Eduardo; Lee, Roland; Osmonavic, Senad; Leeungurasatien, Thidarat; He, Mingguang; Lin, Shan C

    2012-07-01

    To investigate anterior chamber parameters and biometric factors associated with degree of angle opening after laser peripheral iridotomy (LPI) for narrow angles. In this prospective cohort study, patients with narrow angles who were scheduled for LPI were recruited. Anterior chamber parameters by anterior segment coherence tomography (ASOCT) under dark conditions were compared before and after LPI. Only the right eye was used for analysis if both eyes were eligible. Measurements performed by customized software included anterior chamber depth, iris area, angle opening distance at 500 µm (AOD500) anterior to the scleral spur, iris thickness at 750 µm from sclera spur (IT750), trabecular-iris space area 500 (TISA500), and iris curvature (I-Curv). Univariate and multiple regression analyses were performed to determine the predictive factors of angle opening after LPI. Eighty-one patients with narrow angles were prospectively recruited in this study. The AOD500 increased significantly from 0.128 ± 0.081 mm (before) to 0.209 ± 0.087 mm (after) in the nasal quadrant, and from 0.103 ± 0.067 mm (before) to 0.197 ± 0.071 mm (after) in the temporal quadrant (p chamber angle widening after LPI were older age, smaller iris area, and steeper iris.

  19. Contact angle and contact angle hysteresis measurements using the capillary bridge technique.

    Science.gov (United States)

    Restagno, Frédéric; Poulard, Christophe; Cohen, Céline; Vagharchakian, Laurianne; Léger, Liliane

    2009-09-15

    A new experimental technique is proposed to easily measure both advancing and receding contact angles of a liquid on a solid surface, with unprecedented accuracy. The technique is based on the analysis of the evolution of a capillary bridge formed between a liquid bath and a solid surface (which needs to be spherical) when the distance between the surface and the liquid bath is slowly varied. The feasibility of the technique is demonstrated using a low-energy perfluorinated surface with two different test liquids (water and hexadecane). A detailed description of both experimental procedures and computational modeling are given, allowing one to determine contact angle values. It is shown that the origin of the high accuracy of this technique relies on the fact that the contact angles are automatically averaged over the whole periphery of the contact. This method appears to be particularly adapted to the characterization of surfaces with very low contact angle hysteresis.

  20. Introduction to small-angle scattering

    International Nuclear Information System (INIS)

    Gilbert, E.

    2003-01-01

    Full text: Small angle neutron and X-ray scattering (SANS and SAXS) are ideal tools for studying the structure of materials in the size range between 10 and 1000 Angstrom. While imaging methods such as transmission electron microscopy (TEM) also have this capability, they provide images in real space, for instance individual grains in a nanocrystalline material. SANS and SAXS, on the other hand, provide (generally) a non-destructive method yielding structural information averaged over all grains with high statistical accuracy due to averaging over the whole sample volume. The use of neutrons and X-rays is also implicitly complementary due to their sensitivity to either nuclear or electron density respectively. This provides several further advantages over real-space techniques such as isotopic sensitivity and contrast variation. In this talk, I will provide an introduction to the technique with a minimum number of equations, emphasising what structural information may be obtained from small-angle scattering

  1. Fan Stagger Angle for Dirt Rejection

    Science.gov (United States)

    Gallagher, Edward J. (Inventor); Rose, Becky E. (Inventor); Brilliant, Lisa I. (Inventor)

    2015-01-01

    A gas turbine engine includes a spool, a turbine coupled to drive the spool, a propulsor coupled to be rotated about an axis by the turbine through the spool, and a gear assembly coupled between the propulsor and the spool such that rotation of the turbine drives the propulsor at a different speed than the spool. The propulsor includes a hub and a row of propulsor blades that extend from the hub. Each of the propulsor blades has a span between a root at the hub and a tip, and a chord between a leading edge and a trailing edge. The chord forms a stagger angle alpha with the axis, and the stagger angle alpha is less than 15 deg. at a position along the propulsor blade that is within an inboard 20% of the span.

  2. The small angle diffractometer SANS at PSI

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-11-01

    With the start-up of SINQ an instrument for small angle neutron scattering will be operational which compares well with the world`s largest and most powerful facilities of this kind. Following the classical principle of the D11-instrument of ILL, it is equipped with state-of-the-art components as are nowadays available, including options for further upgrading. Great emphasis was laid upon providing a flexible, universal multi-user facility which guarantees a comfortable and reliable operation. In the present paper, the principle layout of the instrument is presented, and the individual components are described in detail. The paper concludes with model application of small angle scattering to a system of dilute CuCo alloys which undergo a phase separation under thermal treatment, forming spherical Co-precipitates dispersed in a Cu-rich matrix. (author) 3 figs., 1 tab., 14 refs.

  3. Didactical Design Enrichment of Angle in Geometry

    Science.gov (United States)

    Setiadi, D. R.; Suryadi, D.; Mulyana, E.

    2017-09-01

    The underlying problem of this research is the lack of student’s competencies in understanding the concept of angle in geometry as the results of the teaching and learning pattern that only to receive the topic rather than to construct the topic and has not paid attention to the learning trajectory. The purpose of this research is to develop the didactical design of angle in space learning activity. The used research method is a method of qualitative research in the form of a didactical design research through three phases of analysis i.e. didactical situation analysis, metapedadidactical analysis, and retrospective analysis, which conducted in students from 10th grade at one of private schools in Bandung. Based on the results of research and discussion, the didactical design that has been made, is capable to change student’s learning habit and quite capable to develop student’s competencies although not optimal.

  4. Exclusive Backward-Angle Omega Meson Electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Wenliang, Li [Univ. of Regina, Regina, SK (Canada)

    2017-10-01

    Exclusive meson electroproduction at different squared four-momenta of the exchanged virtual photon, Q2 , and at different four-momentum transfers, t and u, can be used to probe QCD's transition from hadronic degrees of freedom at the long distance scale to quark-gluon degrees of freedom at the short distance scale. Backward-angle meson electroproduction was previously ignored, but is anticipated to offer complimentary information to conventional forward-angle meson electroproduction studies on nucleon structure. This work is a pioneering study of backward-angle ω cross sections through the exclusive 1H(e, e'p)ω reaction using the missing mass reconstruction technique. The extracted cross sections are separated into the transverse (T), longitudinal (L), and LT, TT interference terms. The analyzed data were part of experiment E01-004 (Fπ-2), which used 2.6-5.2 GeV electron beams and HMS+SOS spectrometers in Jefferson Lab Hall C. The primary objective was to detect coincidence π in the forward-angle, where the backward-angle omega events were fortuitously detected. The experiment has central Q2 values of 1.60 and 2.45 GeV2 , at W = 2.21 GeV. There was significant coverage in phi and epsilon, which allowed separation of σT,L,LT,TT . The data set has a unique u coverage of -u ~ 0, which corresponds to -t > 4 GeV2 . The separated σT result suggest a flat ~ 1/Q1.33±1.21 dependence, whereas sigma_L seems to hold a stronger 1/Q9.43±6.28 dependence. The σL/σT ratio indicate σT dominance at Q2 = 2.45 GeV2 at the ~90% confidence level. After translating the results into the -t space of the published CLAS data, our data show evidence of a backward-angle omega electroproduction peak at both Q2 settings. Previously, this phenomenon showing both forward and backward-angle peaks was only observed in the meson

  5. What's the angle: a study of the angle bisected in intraoral radiography.

    Science.gov (United States)

    Manson-Hing, L R

    1980-01-01

    Intraoral radiographs were made via the bisecting-the-angle technique on patients of different ages, sexes, and races. The tooth-film angles for various areas of the mouth were measured and found to be close to 30 degrees for all areas of the mouth except the mandibular posterior regions. The study was conducted to assist in quick positioning of the x-ray beam in difficult cases.

  6. Measurement of the angle alpha at BABAR

    Energy Technology Data Exchange (ETDEWEB)

    Perez, A.; /Orsay, LAL

    2009-06-25

    The authors present recent measurements of the CKM angle {alpha} using data collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory, operating at the {Upsilon}(4S) resonance. They present constraints on {alpha} from B {yields} {pi}{pi}, B {yields} {rho}{rho} and B {yields} {rho}{pi} decays.

  7. Small-Angle Scattering on Magnetoferritin Nanoparticles

    Science.gov (United States)

    Balejčíková Petrenko, L., VI; Avdeev, MV; Garamus, VM; Almásy, L.; Kopčanský, P.

    2017-05-01

    Magnetoferritin is a synthetically prepared magnetic bio-complex, consisting of apoferritin shell and iron-based nanoparticles. Superparamagnetic behaviour, nanoscale size (about 12 nm) and biological origin allow to use magnetoferritin in various applications. In this report, we present a general overview about basic physicochemical properties of magnetoferritin, as determined by small-angle X-ray and neutron scattering experiments and some interesting references on their potential bio-applications.

  8. Neutron Reflectivity and Grazing Angle Diffraction

    OpenAIRE

    Ankner, J. F.; Majkrzak, C. F.; Satija, S. K.

    1993-01-01

    Over the last 10 years, neutron reflectivity has emerged as a powerful technique for the investigation of surface and interfacial phenomena in many different fields. In this paper, a short review of some of the work on neutron reflectivity and grazing-angle diffraction as well as a description of the current and planned neutron rcflectometers at NIST is presented. Specific examples of the characterization of magnetic, superconducting, and polymeric surfaces and interfaces are included.

  9. Neutron Reflectivity and Grazing Angle Diffraction.

    Science.gov (United States)

    Ankner, J F; Majkrzak, C F; Satija, S K

    1993-01-01

    Over the last 10 years, neutron reflectivity has emerged as a powerful technique for the investigation of surface and interfacial phenomena in many different fields. In this paper, a short review of some of the work on neutron reflectivity and grazing-angle diffraction as well as a description of the current and planned neutron rcflectometers at NIST is presented. Specific examples of the characterization of magnetic, superconducting, and polymeric surfaces and interfaces are included.

  10. Ultra small angle scattering versus diffraction

    Science.gov (United States)

    Ebrahimi, O.; Treimer, W.; Strobl, M.; Feye-Treimer, U.; Beul, N.; Jericha, E.; Seidel, S. O.

    2010-11-01

    In the case of ultra small angle (neutron or x-ray) scattering (USANS, USAXS) it may happen that structures under investigations are not fully coherently illuminated by the incident wave. Despite this fact interference effects are observed similar to SAS data. In this case the measured scattering patterns must be different interpreted. We propose a procedure to calculate and adapt such scattering patterns to experimental data.

  11. Ultra small angle scattering versus diffraction

    International Nuclear Information System (INIS)

    Ebrahimi, O; Treimer, W; Strobl, M; Feye-Treimer, U; Beul, N; Jericha, E; Seidel, S O

    2010-01-01

    In the case of ultra small angle (neutron or x-ray) scattering (USANS, USAXS) it may happen that structures under investigations are not fully coherently illuminated by the incident wave. Despite this fact interference effects are observed similar to SAS data. In this case the measured scattering patterns must be different interpreted. We propose a procedure to calculate and adapt such scattering patterns to experimental data.

  12. Resonances and backward-angle scattering

    International Nuclear Information System (INIS)

    Stokstad, R.G.

    1978-01-01

    The strong enhancement of elastic scattering at large angles observed for systems such as α + 40 Ca and recently for 12 C + 28 Si and 16 O 28 Si was interpreted in terms of entrance channel resonances having a quasi-molecular character. Alternative explanations in terms of potential scattering were also presented. An overview is given of the experimental data and their interpretations. A consistent procedure for the evaluation of the experimental data is discussed. 50 references

  13. Pair creation at large inherent angles

    International Nuclear Information System (INIS)

    Chen, P.; Tauchi, T.; Schroeder, D.V.

    1992-01-01

    In the next-generation linear colliders, the low-energy e + e - pairs created during the collision of high-energy e + e - beams would cause potential deleterious background problems to the detectors. At low collider energies, the pairs are made essentially by the incoherent process, where the pair is created by the interaction of beamstrahlung photons on the individual particles in the oncoming beam. This problem was first identified by Zolotarev, et al. At energies where the beamstrahlung parameter Υ lies approximately in the range 0.6 approx-lt Υ approx-lt 100, pair creation from the beamstrahlung photons is dominated by a coherent process, first noted by Chen. The seriousness of this pair creation problem lies in the transverse momenta that the pair particles carry when leaving the interaction point (IP) with large angles. Since the central issue is the transverse momentum for particles with large angles, the authors notice that there is another source for it. Namely, when the pair particles are created at low energies, the intrinsic angles of these pairs when produced may already be large. In this paper they reinvestigate the problem, following essentially the same equivalent photon approach, but with changes in specific details including the virtual photon spectrum. In addition, various assumptions are made more explicit. The formulas derived are then applied to the collider parameters designed by Palmer

  14. Multi-Angle Snowflake Camera Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Stuefer, Martin [Univ. of Alaska, Fairbanks, AK (United States); Bailey, J. [Univ. of Alaska, Fairbanks, AK (United States)

    2016-07-01

    The Multi-Angle Snowflake Camera (MASC) takes 9- to 37-micron resolution stereographic photographs of free-falling hydrometers from three angles, while simultaneously measuring their fall speed. Information about hydrometeor size, shape orientation, and aspect ratio is derived from MASC photographs. The instrument consists of three commercial cameras separated by angles of 36º. Each camera field of view is aligned to have a common single focus point about 10 cm distant from the cameras. Two near-infrared emitter pairs are aligned with the camera’s field of view within a 10-angular ring and detect hydrometeor passage, with the lower emitters configured to trigger the MASC cameras. The sensitive IR motion sensors are designed to filter out slow variations in ambient light. Fall speed is derived from successive triggers along the fall path. The camera exposure times are extremely short, in the range of 1/25,000th of a second, enabling the MASC to capture snowflake sizes ranging from 30 micrometers to 3 cm.

  15. Off-Angle Iris Correction Methods

    Energy Technology Data Exchange (ETDEWEB)

    Santos-Villalobos, Hector J [ORNL; Thompson, Joseph T [ORNL; Karakaya, Mahmut [ORNL; Boehnen, Chris Bensing [ORNL

    2016-01-01

    In many real world iris recognition systems obtaining consistent frontal images is problematic do to inexperienced or uncooperative users, untrained operators, or distracting environments. As a result many collected images are unusable by modern iris matchers. In this chapter we present four methods for correcting off-angle iris images to appear frontal which makes them compatible with existing iris matchers. The methods include an affine correction, a retraced model of the human eye, measured displacements, and a genetic algorithm optimized correction. The affine correction represents a simple way to create an iris image that appears frontal but it does not account for refractive distortions of the cornea. The other method account for refraction. The retraced model simulates the optical properties of the cornea. The other two methods are data driven. The first uses optical flow to measure the displacements of the iris texture when compared to frontal images of the same subject. The second uses a genetic algorithm to learn a mapping that optimizes the Hamming Distance scores between off-angle and frontal images. In this paper we hypothesize that the biological model presented in our earlier work does not adequately account for all variations in eye anatomy and therefore the two data-driven approaches should yield better performance. Results are presented using the commercial VeriEye matcher that show that the genetic algorithm method clearly improves over prior work and makes iris recognition possible up to 50 degrees off-angle.

  16. Studies in small angle scattering techniques

    International Nuclear Information System (INIS)

    Moellenbach, K.

    1980-03-01

    Small angle scattering of neutrons, X-rays and γ-rays are found among the spectroscopic methods developed in the recent years. Although these techniques differ from each other in many respects, e.g. radiation sources and technical equipment needed, their power to resolve physical phenomena and areas of application can be discussed in a general scheme. Selected examples are given illustrating the use of specific technical methods. Jahn-Teller driven structural phase transitions in Rare Earth zircons were studied with neutron scattering as well as small angle γ-ray diffraction. The study of neutron scattering from formations of magnetic domains in the Ising ferromagnet LiTbF 4 is a second example. Both these examples represent more than experimental test cases since the theoretical interpretations of the data obtained are discussed as well. As a last example the use of small angle scattering methods for the study of molecular biological samples is discussed. In particular the experimental procedures used in connection with scattering from aqueous solutions of proteins and protein complexes are given. (Auth.)

  17. Head flexion angle while using a smartphone.

    Science.gov (United States)

    Lee, Sojeong; Kang, Hwayeong; Shin, Gwanseob

    2015-01-01

    Repetitive or prolonged head flexion posture while using a smartphone is known as one of risk factors for pain symptoms in the neck. To quantitatively assess the amount and range of head flexion of smartphone users, head forward flexion angle was measured from 18 participants when they were conducing three common smartphone tasks (text messaging, web browsing, video watching) while sitting and standing in a laboratory setting. It was found that participants maintained head flexion of 33-45° (50th percentile angle) from vertical when using the smartphone. The head flexion angle was significantly larger (p smartphone, could be a main contributing factor to the occurrence of neck pain of heavy smartphone users. Practitioner Summary: In this laboratory study, the severity of head flexion of smartphone users was quantitatively evaluated when conducting text messaging, web browsing and video watching while sitting and standing. Study results indicate that text messaging while sitting caused the largest head flexion than that of other task conditions.

  18. Research on recognition of ramp angle based on transducer

    Directory of Open Access Journals (Sweden)

    Wenhao GU

    2015-12-01

    Full Text Available Focusing on the recognition of ramp angle, the relationship between the signal of vehicle transducer and real ramp angle is studied. The force change of vehicle on the ramp, and the relationship between the body tilt angle and front and rear suspension scale is discussed. According to the suspension and tire deformation, error angle of the ramp angle is deduced. A mathematical model is established with Matlab/Simulink and used for simulation to generate error curve of ramp angle. The results show that the error angle increases with the increasing of the ramp angle, and the limit value can reach 6.5%, while the identification method can effectively eliminate this error, and enhance the accuracy of ramp angle recognition.

  19. The effect of beam angle in abrasive-waterjet machining

    International Nuclear Information System (INIS)

    Hashish, M.

    1989-01-01

    In the machining of materials, abrasive-waterjets are typically applied at a 90-degree angle to the surface of the workpiece. This paper presents results and observations on machining with abrasive-waterjets at angles other than 90 degrees. Previous visualization studies of the cutting process in transparent materials has shown that there are optimal angles for maximum depth of cut and kerf depth uniformity. Here, observations on the effect of angle in machining applications, such as turning, milling. linear cutting, and drilling, are addressed. The effects of variations in both the impact angle and the rake angle are investigated. Results indicate that the volume removal rate is significantly affected by these angles and that surface finish can be improved by angling the jet. However, shallow angle drilling of small holes in laminated or ceramic-coated materials requires further investigation

  20. [Measurement of the lumbosacral angle and its clinical significance].

    Science.gov (United States)

    Bene, E

    1981-01-01

    The author reports about the result of a series of investigations and tests concerning the angle of the L-S vertebral column. Different factors influencing the values of L-S angle are analyzed. The clinical importance of the respective angles is small, the statics of the L-S transition is determined by all angles together. The reduced L-S angle cannot be considered as an aetiological factor of the spondylolysthesis. The pathological angle values as well as the positions play a role in the induction of the discopathy

  1. A simple method to obtain consistent and clinically meaningful pelvic angles from euler angles during gait analysis.

    Science.gov (United States)

    Wren, Tishya A L; Mitiguy, Paul C

    2007-08-01

    Clinical gait analysis usually describes joint kinematics using Euler angles, which depend on the sequence of rotation. Studies have shown that pelvic obliquity angles from the traditional tilt-obliquity-rotation (TOR) Euler angle sequence can deviate considerably from clinical expectations and have suggested that a rotation-obliquity-tilt (ROT) Euler angle sequence be used instead. We propose a simple alternate approach in which clinical joint angles are defined and exactly calculated in terms of Euler angles from any rotation sequence. Equations were derived to calculate clinical pelvic elevation, progression, and lean angles from TOR and ROT Euler angles. For the ROT Euler angles, obliquity was exactly the same as the clinical elevation angle, rotation was similar to the clinical progression angle, and tilt was similar to the clinical lean angle. Greater differences were observed for TOR. These results support previous findings that ROT is preferable to TOR for calculating pelvic Euler angles for clinical interpretation. However, we suggest that exact clinical angles can and should be obtained through a few extra calculations as demonstrated in this technical note.

  2. Light-dark changes in iris thickness and anterior chamber angle width in eyes with occludable angles.

    Science.gov (United States)

    Hirose, Fumitaka; Hata, Masayuki; Ito, Shin-ichiro; Matsuki, Takaaki; Kurimoto, Yasuo

    2013-10-01

    The purpose of this study was to investigate and measure light-dark changes in iris thickness (IT) and anterior chamber angle width in eyes with occludable angles and open angles by using anterior segment optical coherence tomography (AS-OCT). We examined 153 eyes of 153 Japanese patients with primary angle closure suspect, primary angle closure, primary angle closure glaucoma, or primary open angle glaucoma. AS-OCT was used to determine pupil diameter, IT, angle opening distance at 500 μm (AOD₅₀₀), and trabecular-iris space area at 500 μm (TISA₅₀₀) in each quadrant of the anterior chamber angle (superior, inferior, temporal, and nasal) under light and dark conditions. In the angle closure cases, IT, AOD₅₀₀ and TISA₅₀₀ in the dark varied significantly among the four quadrants (P dark did not differ significantly among the four quadrants. In the angle closure cases and the open angle cases, significant negative associations were found between IT difference [IT(light)-IT(dark)] and AOD₅₀₀ difference [AOD₅₀₀(light)-AOD₅₀₀(dark)] (R = -0.411, P dark)] (R = -0.475, P dark conditions is related to the mechanism of primary angle closure. It is important to analyze both the angle structure and peripheral IT in each quadrant.

  3. Angle parameter changes of phacoemulsification and combined phacotrabeculectomy for acute primary angle closure

    Directory of Open Access Journals (Sweden)

    Shi-Wei Li

    2015-08-01

    Full Text Available AIM: To evaluate the difference in angle parameters and clinical outcome following phacoemulsification and combined phacotrabeculectomy in patients with acute primary angle closure (APAC using ultrasound biomicroscopy (UBM.METHODS: Patients (n=23, 31 eyes were randomized to receive phacoemulsification or combined phacotrabeculectomy (n=24, 31 eyes. Best-corrected visual acuity (BCVA, intraocular pressure (IOP, the main complications following surgery, and indentation gonioscopy and angle parameters measured using UBM were documented preoperatively and postoperatively.RESULTS:The improvement in BCVA in the phacoemulsification group was significantly greater than in the combined group (P<0.05. IOP in the phacoemulsification group was slightly higher than in the combined group following 1wk of follow-up (P<0.05, whereas there was no significant difference between the two groups at the latter follow-up (P>0.05. Phacoemulsification alone resulted in a slight increase in the trabecular ciliary processes distance compared with the combined surgery (P<0.05, whereas the other angle parameters showed no significant difference between the groups. Complications in combined group were greater than phacoemulsification only group.CONCLUSION:Both surgeries effectively opened the drainage angle and deepened the anterior chamber, and IOP was well controlled postoperatively. However, phacoemulsification showed better efficacy in improving visual function and showed reduced complications following surgery.

  4. Optimum transfer between hyperbolic asymptotes with turn angle less than the maximum natural turn angle.

    Science.gov (United States)

    Walton, J. M.; Marchal, C.; Culp, R. D.

    1971-01-01

    The impulsive transfer of minimum characteristic velocity between two given hyperbolic asymptotes associated with a real planet is considered. The constraint of remaining above the surface of the planet introduces a maximum natural turn angle. This divides the problem naively into two categories. The first is the case when the turn angle required by the given asymptotes is less than or equal to the maximum natural turn angle. This is the more reasonable situation for a swingby maneuver, and is the case considered in this paper. The resulting optimal transfers are of five basic types. In boundary conditions space, by far the largest area of transfers are either single impulse transfers or transfers through the parabolic level requiring two finite impulses. In no case has an optimal transfer been found which uses more than two finite impulses and three infinitesimal impulses. Complete results are presented for the case in which the given turn angle is less than or equal to the maximum natural turn angle.

  5. A variable angle slant-hole collimator

    International Nuclear Information System (INIS)

    Moore, R.H.; Alpert, N.M.; Strauss, H.W.

    1983-01-01

    A variable-angle slant-hole (VASH) collimator was constructed to show the feasibility of using multiple sliding plates to achieve a range of collimator channel inclinations. One hundred and sixty tungsten plates, 0.125 mm thick and 14 cm square, were photoetched to produce 3025 1.5-mm2 holes in each plate, separated by 0.8-mm septa. Along with the collimator holes, registration holes and positioning grooves were also etched. The plates were placed in a holder and stacked to form a collimator 2.0 cm high. The holder permitted the plates to be sheared to achieve viewing angles from 0 to 40 degrees from the vertical. Resolution and sensitivity were determined both across and along the shear directions. Resolution of a thin /sup 99m/Tc source, 1.24 mm diam and 7 cm long, located 5 cm from the collimator face in air, was 1.1 cm FWHM at 0 degree shear and remained unchanged with increasing slant. The resolution was similar both across and along the shear plane. Sensitivity was determined with a point source placed 7 cm from the collimator face. At 0 degree slant the sensitivity was 169 cps/MBq (6.24 csp/mu Ci). A general all purpose (GAP) collimator had a FWHM of 1 cm for the line source in air at 5 cm, and a sensitivity of 205 cps/MBq (7.58 cps/mu Ci) for the point source at 7 cm. The data suggest that a variable-angle slant-hole collimator can be constructed of laminated plates

  6. The Sphaleron at finite mixing angle

    International Nuclear Information System (INIS)

    Klinkhamer, F.R.; Laterveer, R.

    1990-01-01

    The exact Sphaleron solution in the bosonic sector of the electro-weak standard model is only known for weak mixing angle θ W =0. To investigate the behaviour closer to the experimental value θ W exp approx 30 deg a non-contractible loop in configuration space which is sensitive to θ W is constructed. The numerical results for the energy and the magnetic dipole moment indicate that the dependence on θ W is rather weak. (author). 8 refs.; 4 figs.; 1 tab

  7. Spin Valve Systems for Angle Sensor Applications

    OpenAIRE

    Johnson, Andrew

    2004-01-01

    A contact-less sensor with the ability to measure over a 360° range has been long sought after in the automotive industry. Such a sensor could be realized by utilizing the angle dependence of the Giant Magneto Resistance (GMR) Effect in a special type of magnetic multilayer called a spin valve arranged in a wheatstone bridge circuit [Spo96]. A spin valve consists of two ferromagnetic layers separated by nonmagnetic spacer layer where the magnetization of one of the ferromagnetic layers is pin...

  8. Pair production in small angle Bhabha scattering

    International Nuclear Information System (INIS)

    Arbuzov, A.B.; Kuraev, Eh.A.; Merenkov, N.P.; Trentadue, L.

    1995-01-01

    The radiative corrections due to a pair production in the small angle high energy e + e - Bhabha scattering are considered. The corrections due to the production of virtual pairs as well as real soft and hard ones are calculated analytically. The collinear and semi-collinear kinematical regions of the hard pair production are taken into account. The results in the leading and next-to-leading logarithmic approximations provide the accuracy of Ο (0.1%). The results of numerical calculations show that the effects of pairs production are to be taken into account in the precise luminosity determination at LEP. 9 refs., 3 figs., 2 tabs

  9. Joining by plating: optimization of occluded angle

    International Nuclear Information System (INIS)

    Dini, J.W.; Johnson, H.R.; Kan, Y.R.

    1978-11-01

    An empirical method has been developed for predicting the minimum angle required for maximum joint strength for materials joined by plating. This is done through a proposed power law failure function, whose coefficients are taken from ring shear and conical head tensile data for plating/substrate combinations and whose exponent is determined from one set of plated-joint data. Experimental results are presented for Al-Ni-Al (7075-T6) and AM363-Ni-AM363 joints, and the failure function is used to predict joint strengths for Al-Ni-Al (2024-T6), UTi-Ni-UTi, and Be-Ti-Be

  10. Rapidly-Indexing Incremental-Angle Encoder

    Science.gov (United States)

    Christon, Philip R.; Meyer, Wallace W.

    1989-01-01

    Optoelectronic system measures relative angular position of shaft or other device to be turned, also measures absolute angular position after device turned through small angle. Relative angular position measured with fine resolution by optoelectronically counting finely- and uniformly-spaced light and dark areas on encoder disk as disk turns past position-sensing device. Also includes track containing coarsely- and nonuniformly-spaced light and dark areas, angular widths varying in proportion to absolute angular position. This second track provides gating and indexing signal.

  11. Weak mixing angles and heavy flavours

    International Nuclear Information System (INIS)

    Jarlskog, C.

    1984-05-01

    The present status of the weak mixing angles, in the standard six quark model, is reviewed. The implications of the recent measurements of the beauty lifetime and branching ratios are discussed, in the framework of the Kobayashi-Maskawa and the Wolfenstein parametrizations. Expectations for B(sup)o - B(sup)-o mixing and consequences for the collider data are given. Other topics briefly reviewed are CP-violation, top quark mass and possible implications of the existence of a fourth family. (author)

  12. Lateral angle: a method for sexing using the petrous bone

    DEFF Research Database (Denmark)

    Norén, Anna; Lynnerup, Niels; Czarnetzki, Alfred

    2005-01-01

    We report on the results of applying the so-called lateral angle method for sex determination on skeletal remains. The lateral angle denotes the angle of the internal auditory canal in relation to the medial surface of the petrous part of the temporal bone. The method involves making a small cast...... and females (mean angle size of males, 39.3 degrees ; mean angle size of females, 48.2 degrees ; P lateral angle method against an archaeological skeletal...... sample. True sex was not known for this sample; instead, sexing had been carried out by assessing pelvic and cranial morphology in independent trials. We found a higher concordance between the lateral angle and "pelvic" sex than for lateral angle and "cranial" sex. Finally, we note that subadult sexing...

  13. Measurement of Angle Kappa Using Ultrasound Biomicroscopy and Corneal Topography.

    Science.gov (United States)

    Yeo, Joon Hyung; Moon, Nam Ju; Lee, Jeong Kyu

    2017-06-01

    To introduce a new convenient and accurate method to measure the angle kappa using ultrasound biomicroscopy (UBM) and corneal topography. Data from 42 eyes (13 males and 29 females) were analyzed in this study. The angle kappa was measured using Orbscan II and calculated with UBM and corneal topography. The angle kappa of the dominant eye was compared with measurements by Orbscan II. The mean patient age was 36.4 ± 13.8 years. The average angle kappa measured by Orbscan II was 3.98° ± 1.12°, while the average angle kappa calculated with UBM and corneal topography was 3.19° ± 1.15°. The difference in angle kappa measured by the two methods was statistically significant (p topography to calculate the angle kappa. This method is convenient to use and allows for measurement of the angle kappa without an expensive device. © 2017 The Korean Ophthalmological Society

  14. Apparatus and method for variable angle slant hole collimator

    Science.gov (United States)

    Lee, Seung Joon; Kross, Brian J.; McKisson, John E.

    2017-07-18

    A variable angle slant hole (VASH) collimator for providing collimation of high energy photons such as gamma rays during radiological imaging of humans. The VASH collimator includes a stack of multiple collimator leaves and a means of quickly aligning each leaf to provide various projection angles. Rather than rotate the detector around the subject, the VASH collimator enables the detector to remain stationary while the projection angle of the collimator is varied for tomographic acquisition. High collimator efficiency is achieved by maintaining the leaves in accurate alignment through the various projection angles. Individual leaves include unique angled cuts to maintain a precise target collimation angle. Matching wedge blocks driven by two actuators with twin-lead screws accurately position each leaf in the stack resulting in the precise target collimation angle. A computer interface with the actuators enables precise control of the projection angle of the collimator.

  15. Kernel density estimation applied to bond length, bond angle, and torsion angle distributions.

    Science.gov (United States)

    McCabe, Patrick; Korb, Oliver; Cole, Jason

    2014-05-27

    We describe the method of kernel density estimation (KDE) and apply it to molecular structure data. KDE is a quite general nonparametric statistical method suitable even for multimodal data. The method generates smooth probability density function (PDF) representations and finds application in diverse fields such as signal processing and econometrics. KDE appears to have been under-utilized as a method in molecular geometry analysis, chemo-informatics, and molecular structure optimization. The resulting probability densities have advantages over histograms and, importantly, are also suitable for gradient-based optimization. To illustrate KDE, we describe its application to chemical bond length, bond valence angle, and torsion angle distributions and show the ability of the method to model arbitrary torsion angle distributions.

  16. The impact of inlet angle and outlet angle of guide vane on pump in reversal based hydraulic turbine performance

    International Nuclear Information System (INIS)

    Shi, F X; Yang, J H; Wang, X H; Zhang, R H; Li, C E

    2012-01-01

    In this paper, in order to research the impact of inlet angle and outlet angle of guide vane on hydraulic turbine performance, a centrifugal pump in reversal is adopted as turbine. A numerical simulation method is adopted for researching outer performance and flow field of turbine. The results show: inlet angle has a crucial role to turbine, to the same flow, there is a noticeable decline for the efficiency and head of turbine with the inlet angle increases. At the best efficiency point(EFP),to a same inlet angle, when the inlet angle greater than inlet angle, velocity circulation in guide vane outlet decreases, which lead the efficiency of turbine to reduce, Contrarily, the efficiency rises. With the increase of inlet angle and outlet angle, the EFP moves to the big flow area and the uniformity of pressure distribution becomes worse. The paper indicates that the inlet angle and outlet angle have great impact on the turbine performance, and the best combination exists for the inlet angle and outlet angle of the guide vane.

  17. Paddle Angle and Ball Spin in Table Tennis

    Directory of Open Access Journals (Sweden)

    Binvant Broca

    2017-01-01

    Full Text Available The relationship between the impact angle of a table tennis ball with respect to the paddle and angular velocity of the ball leaving the paddle was investigated. A table tennis ball was dropped onto a paddle oriented at impact angles ranging from 10° to 80°. It was found that the sine of the impact angle is proportional to the angular velocity of the ball as it leaves the paddle for all impact angles tested.

  18. Cluster headache or narrow angle glaucoma?

    Directory of Open Access Journals (Sweden)

    Prasad Palimar

    1991-01-01

    Full Text Available A 47 year old man with episodes of attacks of pain, redness and mild blurring of vision was investigated for narrow angle glaucoma in view of shallow anterior chambers and a cupped optic disc. The history was reviewed following a spontaneous attack in hospital, which had features other than acute glaucoma. A diagnosis of cluster headache was made on the basis of tests. Cluster headache has been defined as unilateral intense pain, involving the eye and head on one side, usually associated with flushing, nasal congestion and lacrimation; the attacks recurring one or more times daily and lasting 20 - 120 minutes. Such attacks commonly continue for weeks or months and are separated by an asymptomatic period of months to years. This episodic nature, together with unilaterality and tendency to occur at night, closely mimics narrow angle glaucoma. Further, if patients have shallow anterior chambers and disc cupping, the differentiation becomes more difficult yet critical. Resource to provocative tests is often the only answer as the following case report demonstrates.

  19. Metasurface Enabled Wide-Angle Fourier Lens.

    Science.gov (United States)

    Liu, Wenwei; Li, Zhancheng; Cheng, Hua; Tang, Chengchun; Li, Junjie; Zhang, Shuang; Chen, Shuqi; Tian, Jianguo

    2018-04-19

    Fourier optics, the principle of using Fourier transformation to understand the functionalities of optical elements, lies at the heart of modern optics, and it has been widely applied to optical information processing, imaging, holography, etc. While a simple thin lens is capable of resolving Fourier components of an arbitrary optical wavefront, its operation is limited to near normal light incidence, i.e., the paraxial approximation, which puts a severe constraint on the resolvable Fourier domain. As a result, high-order Fourier components are lost, resulting in extinction of high-resolution information of an image. Other high numerical aperture Fourier lenses usually suffer from the bulky size and costly designs. Here, a dielectric metasurface consisting of high-aspect-ratio silicon waveguide array is demonstrated experimentally, which is capable of performing 1D Fourier transform for a large incident angle range and a broad operating bandwidth. Thus, the device significantly expands the operational Fourier space, benefitting from the large numerical aperture and negligible angular dispersion at large incident angles. The Fourier metasurface will not only facilitate efficient manipulation of spatial spectrum of free-space optical wavefront, but also be readily integrated into micro-optical platforms due to its compact size. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Anomalous and resonance small-angle scattering

    International Nuclear Information System (INIS)

    Epperson, J.E.; Thiyagarajan, P.

    1988-01-01

    Significant changes in the small-angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous-dispersion terms for the scattering factor (X-rays) or scattering length (neutrons). The physics inherent in these anomalous-dispersion terms is first discussed before consideration of how they enter the relevant scattering theory. Two major areas of anomalous-scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with X-rays. However, it is pointed out that the formalism is the same for the analog experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small-angle neutron scattering are discussed. (orig.)

  1. Anomalous and resonance small angle scattering

    International Nuclear Information System (INIS)

    Epperson, J.E.; Thiyagarajan, P.

    1987-11-01

    Significant changes in the small angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous dispersion terms for the scattering factor (x-rays) or scattering length (neutrons). The physics inherent in these anomalous dispersion terms is first discussed before considering how they enter the relevant scattering theory. Two major areas of anomalous scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with x-rays. However, it is pointed out that the formalism is the same or the analogue experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small-angle neutron scatterings are discussed. 8 figs

  2. A LEGO Mindstorms Brewster angle microscope

    Science.gov (United States)

    Fernsler, Jonathan; Nguyen, Vincent; Wallum, Alison; Benz, Nicholas; Hamlin, Matthew; Pilgram, Jessica; Vanderpoel, Hunter; Lau, Ryan

    2017-09-01

    A Brewster Angle Microscope (BAM) built from a LEGO Mindstorms kit, additional LEGO bricks, and several standard optics components, is described. The BAM was built as part of an undergraduate senior project and was designed, calibrated, and used to image phospholipid, cholesterol, soap, and oil films on the surface of water. A BAM uses p-polarized laser light reflected off a surface at the Brewster angle, which ideally yields zero reflectivity. When a film of different refractive index is added to the surface a small amount of light is reflected, which can be imaged in a microscope camera. Films of only one molecule (approximately 1 nm) thick, a monolayer, can be observed easily in the BAM. The BAM was used in a junior-level Physical Chemistry class to observe phase transitions of a monolayer and the collapse of a monolayer deposited on the water surface in a Langmuir trough. Using a photometric calculation, students observed a change in thickness of a monolayer during a phase transition of 7 Å, which was accurate to within 1 Å of the value determined by more advanced methods. As supplementary material, we provide a detailed manual on how to build the BAM, software to control the BAM and camera, and image processing software.

  3. SU-E-T-446: Group-Sparsity Based Angle Generation Method for Beam Angle Optimization

    International Nuclear Information System (INIS)

    Gao, H

    2015-01-01

    Purpose: This work is to develop the effective algorithm for beam angle optimization (BAO), with the emphasis on enabling further improvement from existing treatment-dependent templates based on clinical knowledge and experience. Methods: The proposed BAO algorithm utilizes a priori beam angle templates as the initial guess, and iteratively generates angular updates for this initial set, namely angle generation method, with improved dose conformality that is quantitatively measured by the objective function. That is, during each iteration, we select “the test angle” in the initial set, and use group-sparsity based fluence map optimization to identify “the candidate angle” for updating “the test angle”, for which all the angles in the initial set except “the test angle”, namely “the fixed set”, are set free, i.e., with no group-sparsity penalty, and the rest of angles including “the test angle” during this iteration are in “the working set”. And then “the candidate angle” is selected with the smallest objective function value from the angles in “the working set” with locally maximal group sparsity, and replaces “the test angle” if “the fixed set” with “the candidate angle” has a smaller objective function value by solving the standard fluence map optimization (with no group-sparsity regularization). Similarly other angles in the initial set are in turn selected as “the test angle” for angular updates and this chain of updates is iterated until no further new angular update is identified for a full loop. Results: The tests using the MGH public prostate dataset demonstrated the effectiveness of the proposed BAO algorithm. For example, the optimized angular set from the proposed BAO algorithm was better the MGH template. Conclusion: A new BAO algorithm is proposed based on the angle generation method via group sparsity, with improved dose conformality from the given template. Hao Gao was partially supported by the

  4. Evaluation of the normal calcaneal angles in Egyptian population

    African Journals Online (AJOL)

    Fahmy Anwar Shoukry

    2012-02-01

    Feb 1, 2012 ... ison of the angles according to the side), independent t-test was used to compare the angles according to the sex), distribution of the angles within different age groups was compared with one way analysis of variance (ANOVA) test. The level of sig- nificance was set at p < 0.05, and compared the results of.

  5. Objectifying the Adjacent and Opposite Angles: A Cultural Historical Analysis

    Science.gov (United States)

    Daher, Wajeeh; Musallam, Nadera

    2018-01-01

    The angle topic is central to the development of geometric knowledge. Two of the basic concepts associated with this topic are the adjacent and opposite angles. It is the goal of the present study to analyze, based on the cultural historical semiotics framework, how high-achieving seventh grade students objectify the adjacent and opposite angles'…

  6. Small angle neutron scattering from glassy SiO2

    International Nuclear Information System (INIS)

    Spooner, S.; Hastings, J.B.

    1976-01-01

    The present investigation of neutron scattering from glassy silica was undertaken to resolve whether the small angle scattering observed by Renninger and Uhlmann could also be seen in the bulk samples typically used in neutron-scattering experiments. Within the rather large error bars of this experiment no small angle scattering increase at small angles could be seen. (Auth.)

  7. Goniodysgenesis in familial primary open-angle glaucoma

    NARCIS (Netherlands)

    Verbraak, F. D.; vd Berg, W.; Delleman, J. W.; Greve, E. L.

    1994-01-01

    Results of a pilot study to evaluate goniodysgenesis as a cause of familial open-angle glaucoma are reported. Patients with a familial high tension open-angle glaucoma and a goniodysgenetic chamber angle (n = 11), a number of their relatives with glaucoma (n = 12), and their relatives without

  8. Cubic Equations and the Ideal Trisection of the Arbitrary Angle

    Science.gov (United States)

    Farnsworth, Marion B.

    2006-01-01

    In the year 1837 mathematical proof was set forth authoritatively stating that it is impossible to trisect an arbitrary angle with a compass and an unmarked straightedge in the classical sense. The famous proof depends on an incompatible cubic equation having the cosine of an angle of 60 and the cube of the cosine of one-third of an angle of 60 as…

  9. Fostering Students' Development of the Concept of Angles Using Technology

    Science.gov (United States)

    Richardson, Sue Ellen; Koyunkaya, Melike Yigit

    2017-01-01

    We have used "GeoGebra," a dynamic geometry software environment, to explore how Year 4 students understand definitions of angles. Seven students defined angle and then completed several activities adapted for the dynamic environment. Afterward, students again shared their definitions of angles. We found that even a short investigation…

  10. 47 CFR 25.205 - Minimum angle of antenna elevation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Minimum angle of antenna elevation. 25.205... SATELLITE COMMUNICATIONS Technical Standards § 25.205 Minimum angle of antenna elevation. (a) Earth station antennas shall not normally be authorized for transmission at angles less than 5° measured from the...

  11. Using Digital Technology to See Angles from Different Angles. Part 1: Corners

    Science.gov (United States)

    Host, Erin; Baynham, Emily; McMaster, Heather

    2014-01-01

    In Part 1 of their article, Erin Host, Emily Baynham and Heather McMaster use a combination of digital technology and concrete materials to explore the concept of "corners". They provide a practical, easy to follow sequence of activities that builds on students' understandings. [For "Using Digital Technology to See Angles from…

  12. Scattering angle-based filtering via extension in velocity

    KAUST Repository

    Kazei, Vladimir

    2016-09-06

    The scattering angle between the source and receiver wavefields can be utilized in full-waveform inversion (FWI) and in reverse-time migration (RTM) for regularization and quality control or to remove low frequency artifacts. The access to the scattering angle information is costly as the relation between local image features and scattering angles has non-stationary nature. For the purpose of a more efficient scattering angle information extraction, we develop techniques that utilize the simplicity of the scattering angle based filters for constantvelocity background models. We split the background velocity model into several domains with different velocity ranges, generating an

  13. Spondylolysis and the sacro-horizontal angle in athletes

    International Nuclear Information System (INIS)

    Swaerd, L.; Hellstroem, M.; Jacobsson, B.; Peterson, L.; Sahlgrenska Sjukhuset, Goeteborg; King Faisal Specialist Hospital and Research Centre, Riyadh

    1989-01-01

    The frequency of spondylolysis and the relationship between spondylolysis and the sacro-horizontal angle in 143 athletes and 30 non-athletes is reported. Athletes had a larger sacro-horizontal angle than non-athletes. The sacro-horizontal angle was larger in athletes with spondylolysis as compared with those without. An increased incidence of spondylolysis with an increased angle was demonstrated. It is suggested that an increased sacro-horizontal angle may predispose to spondylolysis, especially in combination with the high mechanical loads sustained in certain sports. (orig.)

  14. Spondylolysis and the sacro-horizontal angle in athletes

    Energy Technology Data Exchange (ETDEWEB)

    Swaerd, L.; Hellstroem, M.; Jacobsson, B.; Peterson, L. (Oestra Sjukhuset, Goeteborg (Sweden). Dept. of Orthopaedics; Sahlgrenska Sjukhuset, Goeteborg (Sweden). Dept. of Diagnostic Radiology; King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia). Dept. of Radiology)

    The frequency of spondylolysis and the relationship between spondylolysis and the sacro-horizontal angle in 143 athletes and 30 non-athletes is reported. Athletes had a larger sacro-horizontal angle than non-athletes. The sacro-horizontal angle was larger in athletes with spondylolysis as compared with those without. An increased incidence of spondylolysis with an increased angle was demonstrated. It is suggested that an increased sacro-horizontal angle may predispose to spondylolysis, especially in combination with the high mechanical loads sustained in certain sports. (orig.).

  15. Sinusoidal Order Estimation Using Angles between Subspaces

    Directory of Open Access Journals (Sweden)

    Søren Holdt Jensen

    2009-01-01

    Full Text Available We consider the problem of determining the order of a parametric model from a noisy signal based on the geometry of the space. More specifically, we do this using the nontrivial angles between the candidate signal subspace model and the noise subspace. The proposed principle is closely related to the subspace orthogonality property known from the MUSIC algorithm, and we study its properties and compare it to other related measures. For the problem of estimating the number of complex sinusoids in white noise, a computationally efficient implementation exists, and this problem is therefore considered in detail. In computer simulations, we compare the proposed method to various well-known methods for order estimation. These show that the proposed method outperforms the other previously published subspace methods and that it is more robust to the noise being colored than the previously published methods.

  16. Angle-resolved photoemission extended fine structure

    International Nuclear Information System (INIS)

    Barton, J.J.

    1985-03-01

    Measurements of the Angle-Resolved Photoemission Extended Fine Structure (ARPEFS) from the S(1s) core level of a c(2 x 2)S/Ni(001) are analyzed to determine the spacing between the S overlayer and the first and second Ni layers. ARPEFS is a type of photoelectron diffraction measurement in which the photoelectron kinetic energy is swept typically from 100 to 600 eV. By using this wide range of intermediate energies we add high precision and theoretical simplification to the advantages of the photoelectron diffraction technique for determining surface structures. We report developments in the theory of photoelectron scattering in the intermediate energy range, measurement of the experimental photoemission spectra, their reduction to ARPEFS, and the surface structure determination from the ARPEFS by combined Fourier and multiple-scattering analyses. 202 refs., 67 figs., 2 tabs

  17. Experimental bounds on sterile neutrino mixing angles

    CERN Document Server

    Ruchayskiy, Oleg

    2012-01-01

    We derive bounds on the mixing between the left-chiral ("active") and the right-chiral ("sterile") neutrinos, provided from the combination of neutrino oscillation data and direct experimental searches for sterile neutrinos. We demonstrate that the mixing of sterile neutrinos with any flavour can be significantly suppressed, provided that the angle theta_13 is non-zero. This means that the lower bounds on sterile neutrino lifetime, coming from the negative results of direct experimental searches can be relaxed (by as much as the order of magnitude at some masses). We also demonstrate that the results of the negative searches of sterile neutrinos with PS191 and CHARM experiments are not applicable directly to the see-saw models. The reinterpretation of these results provides up to the order of magnitude stronger bounds on sterile neutrino lifetime than previously discussed in the literature. We discuss the implications of our results for the Neutrino Minimal Standard Model (the NuMSM).

  18. Vascular anomalies of the cerebellopontine angle

    International Nuclear Information System (INIS)

    Papanagiotou, P.; Grunwald, I.Q.; Politi, M.; Struffert, T.; Ahlhelm, F.; Reith, W.

    2006-01-01

    Vascular anomalies of the cerebellopontine angle are rare compared to tumors in this area. Irritation of the trigeminal, facial, or vestibulocochlear nerve may cause trigeminal neuralgia, hemifacial spasm and vertigo, or tinnitus accordingly. Vessel loops in the cerebellopontine cisterns may cause compression at the root entry or exit zone of the cranial nerves V, VII, and VIII, a phenomenon which is called ''vascular loop syndrome.'' Megadolichobasilar artery and aneurysms of the vertebrobasilar system can also lead to dislocation and compression of the cranial nerves and brain stem. Three-dimensional CISS MR imaging and MR angiography are useful in the detection of neurovascular compression. Microvascular decompression is an effective surgical procedure in the management of compression syndromes of the cranial nerves V, VII, and VIII. (orig.) [de

  19. Foreign Body Embedded in Anterior Chamber Angle

    Directory of Open Access Journals (Sweden)

    Shmuel Graffi

    2012-01-01

    Full Text Available Introduction. We present a case of a metallic foreign body embedded in the anterior chamber angle. After standing in close proximity to a construction worker breaking a tile, a 26-year-old woman using soft contact lens for the correction of mild myopia presented to emergency department for evaluation of a foreign body sensation of her right eye. Methods and Results. Diagnosis was confirmed by gonioscopic examination and a noncontrast CT scan of head and orbits. The foreign body was removed by an external approach without utilizing a magnet. The patient's final outcome was favorable. Discussion. The above is a rare clinical situation, which is impossible to detect on slit-lamp examination without a gonioscopic view. Proper imaging and a specific management are mandatory in order to achieve favorable outcome.

  20. Transmission-type angle deviation microscopy

    International Nuclear Information System (INIS)

    Chiu, M.-H.; Lai, C.-W.; Tan, C.-T.; Lai, C.-F.

    2008-01-01

    We present a new microscopy technique that we call transmission angle deviation microscopy (TADM). It is based on common-path heterodyne interferometry and geometrical optics. An ultrahigh sensitivity surface plasmon resonance (SPR) angular sensor is used to expand dynamic measurement ranges and to improve the axial resolution in three-dimensional optical microscopy. When transmitted light is incident upon a specimen, the beam converges or diverges because of refractive and/or surface height variations. Advantages include high axial resolution (∼32 nm), nondestructive and noncontact measurement, and larger measurement ranges (± 80 μm) for a numerical aperture of 0.21in a transparent measurement medium. The technique can be used without conductivity and pretreatment

  1. Mirtazapine-induced acute angle closure

    Directory of Open Access Journals (Sweden)

    Nilay Kahraman

    2015-01-01

    Full Text Available Acute angle closure (AAC is an ocular emergency with symptoms including blurred vision, eye pain, headache, nausea, vomiting and reddening of the eye those results from increased intraocular pressure. This clinical condition can lead to permanent damage in vision, thus causing blindness by generating progressive and irreversible optic neuropathy if left untreated. There are several reasons of AAC, including several types of local and systemic medications; mainly sympathomimetics, cholinergics, anti-cholinergics, mydriatics, anti-histamines, antiepileptics like topiramate, tricyclic and tetracyclic antidepressants, serotonin reuptake inhibitors, antipsychotics, sulfa-based drugs and anticoagulants. Mirtazapine, a noradrenergic and specific serotonergic antidepressant, is an atypical antidepressant with a complex pharmacological profile. This case report describes a patient with major depressive disorder, who experienced AAC after the first dosage of mirtazapine treatment, and highlights the importance of close monitoring of individuals under antidepressant treatment particularly immediately after initiation of the drug.

  2. Multifunctional patchy particles by glancing angle deposition.

    Science.gov (United States)

    Pawar, Amar B; Kretzschmar, Ilona

    2009-08-18

    The application of glancing angle deposition (GLAD) as a means to produce a variety of multifunctional patchy particles is reported. The GLAD technique has been previously used to produce anisotropic particles with an anisotropy dimension of "patchiness". Here, we extend the technique to produce multifunctional patchy particles with anisotropy dimensions of "patchiness", "branching", and "chemical ordering". To access the entire particle surface, a particle stamping technique is employed using a polydimethylsiloxane (PDMS) stamp. The particle stamping technique along with GLAD yields multifunctional patchy particles having patches on opposite poles. The potential of the developed techniques in producing a wide variety of surface-anisotropic particles with variable patch size, shape, and orientation is demonstrated.

  3. Wide Angle Michelson Doppler Imaging Interferometer (WAMDII)

    Science.gov (United States)

    Roberts, B.

    1986-01-01

    The wide angle Michelson Doppler imaging interferometer (WAMDII) is a specialized type of optical Michelson interferometer working at sufficiently long path difference to measure Doppler shifts and to infer Doppler line widths of naturally occurring upper atmospheric Gaussian line emissions. The instrument is intended to measure vertical profiles of atmospheric winds and temperatures within the altitude range of 85 km to 300 km. The WAMDII consists of a Michelson interferometer followed by a camera lens and an 85 x 106 charge coupled device photodiode array. Narrow band filters in a filter wheel are used to isolate individual line emissions and the lens forms an image of the emitting region on the charge coupled device array.

  4. Contact angle measurement of natural materials.

    Science.gov (United States)

    Zhao, Tianyi; Jiang, Lei

    2018-01-01

    Contact angle (CA) is the most important parameter used to quantify the wettability of solid surfaces. In order to evaluate wettability performance, numerous methods have been developed to measure the CA of solid surfaces. Recent years have seen increased focus on the special wettability performance of various biological materials. Biomimetic wettability has become one of the most popular research fields, and novel CA measurements have been invented accordingly. In this protocol, we introduce several CA measurement techniques mainly based on the image capture method, which is commonly to investigate the wettability of natural materials. According to the solid/liquid/gas context, we classify CA measurements into three types: in air, under liquid, and air bubble measurements, and describe methods for each. The precise measurement of CA together with study of surface structure can reveal the mechanisms of special wettability, thus accelerating the investigation of biomaterials. Copyright © 2017. Published by Elsevier B.V.

  5. Dilemma of gonial angle measurement: Panoramic radiograph or lateral cephalogram

    Energy Technology Data Exchange (ETDEWEB)

    Radhakrishnan, Pillai Devu; Varma, Nilambur Kovilakam Sapna; Ajith, Vallikat Velath [Dept. of Orthodontics, Amrita School of Dentistry, Kochi (India)

    2017-06-15

    The purpose of this study was to evaluate the accuracy of panoramic imaging in measuring the right and left gonial angles by comparing the measured angles with the angles determined using a lateral cephalogram of adult patients with class I malocclusion. The gonial angles of 50 class I malocclusion patients (25 males and 25 females; mean age: 23 years) were measured using both a lateral cephalogram and a panoramic radiograph. In the lateral cephalograms, the gonial angle was measured at the point of intersection of the ramus plane and the mandibular plane. In the panoramic radiographs, the gonial angle was measured by drawing a line tangent to the lower border of the mandible and another line tangent to the distal border of the ascending ramus and the condyle on both sides. The data obtained from both radiographs were statistically compared. No statistically significant difference was observed between the gonial angle measured using the lateral cephalograms and that determined using the panoramic radiographs. Further, there was no statistically significant difference in the measured gonial angle with respect to gender. The results also showed a statistically insignificant difference in the mean of the right and the left gonial angles measured using the panoramic radiographs. As the gonial angle measurements using panoramic radiographs and lateral cephalograms showed no statistically significant difference, panoramic radiography can be considered in orthodontics for measuring the gonial angle without any interference due to superimposed images.

  6. Marine target detection in quad-pol synthetic aperture radar imagery based on the relative phase of cross-polarized channels

    Science.gov (United States)

    Wang, Yunhua; Li, Huimin; Zhang, Yanmin; Guo, Lixin

    2015-01-01

    A focus on marine target detection in noise corrupted fully polarimetric synthetic aperture radar (SAR) is presented. The property of the relative phase between two cross-polarized channels reveals that the relative phases evaluated within sea surface area or noise corrupted area are widely spread phase angle region [-π,π] due to decorrelation effect; however, the relative phases are concentrated to zero and ±π for real target and its first-order azimuth ambiguities (FOAAs), respectively. Exploiting this physical behavior, the reciprocal of the mean square value of the relative phase (RMSRP) is defined as a new parameter for target detection, and the experiments based on fully polarimetric Radarsat-2 SAR images show that the strong noise and the FOAAs can be effectively suppressed in RMSRP image. Meanwhile, validity of the new parameter for target detection is also verified by two typical Radarsat-2 SAR images, in which targets' ambiguities and strong noise are present.

  7. Influence of anterior segment biometric parameters on the anterior chamber angle width in eyes with angle closure.

    Science.gov (United States)

    Matsuki, Takaaki; Hirose, Fumitaka; Ito, Shin-Ichiro; Hata, Masayuki; Hirami, Yasuhiko; Kurimoto, Yasuo

    2015-02-01

    To predict angle narrowing in eyes with angle closure in a Japanese population using anterior segment optical coherence tomography (AS-OCT) quantitative parameters. AS-OCT was used to examine 118 eyes of 118 patients with angle closure and 40 eyes of 40 patients with open angle under dark conditions. After measuring the angle opening distance 500 (AOD500), anterior chamber depth, iris thickness (IT), iris convexity (IC), pupil diameter, anterior chamber width, and crystalline lens rise, multivariate regression analyses were performed for the AOD500 in each group. With the exception of IT, significant differences were observed between the AS-OCT parameters for the angle closure and open-angle groups. Anterior chamber depth, IT, and IC were the explanatory variables associated with AOD500 for each group (P≤0.001). A significant negative association was found between IT and IC only in the angle-closure group (Pchamber depth was a major mechanism of angle narrowing, and that both IT and IC had a strong impact on angle narrowing. Moreover, the negative association found between IT and IC in only the angle closure group indicated the existence of the stretch force placed on the iris by relative pupillary block.

  8. Multi-angle Imaging SpectroRadiometer

    Science.gov (United States)

    Diner, David J. (Principal Investigator)

    MISR views the sunlit Earth simultaneously at nine widely spaced angles and provides ongoing global coverage with high spatial detail. Its imagery is carefully calibrated to provide accurate measures of the brightness, contrast, and color of reflected sunlight. MISR provides new types of information for scientists studying Earth's climate, such as the regional and global distribution of different types of atmospheric particles and aerosols. The change in reflection at different view angles provides the means to distinguish aerosol types, cloud forms, and land surface cover. Combined with stereoscopic techniques, this enables construction of 3-D cloud models and estimation of the total amount of sunlight reflected by Earth's diverse environments. MISR was built for NASA by the Jet Propulsion Laboratory (JPL) in Pasadena, California. It is part of NASA's first Earth Observing System (EOS) spacecraft, the Terra spacecraft, which was launched into polar orbit from Vandenberg Air Force Base on December 18, 1999. MISR has been continuously providing data since February 24, 2000. [Mission Objectives] The MISR instrument acquires systematic multi-angle measurements for global monitoring of top-of-atmosphere and surface albedos and for measuring the shortwave radiative properties of aerosols, clouds, and surface scenes in order to characterize their impact on the Earth's climate. The Earth's climate is constantly changing -- as a consequence of both natural processes and human activities. Scientists care a great deal about even small changes in Earth's climate, since they can affect our comfort and well-being, and possibly our survival. A few years of below-average rainfall, an unusually cold winter, or a change in emissions from a coal-burning power plant, can influence the quality of life of people, plants, and animals in the region involved. The goal of NASA's Earth Observing System (EOS) is to increase our understanding of the climate changes that are occurring on our

  9. The EUVE Right Angle Program (RAP)

    Science.gov (United States)

    Sommers, J.; Christian, D.; Craig, N.; Jessop, H.; Stroozas, B.

    1996-05-01

    The Extreme Ultraviolet Explorer (EUVE ) has three scanning telescopes that observe in a direction perpendicular to that of the primary guest observer (GO) telescope---the Deep Survey/Spectrometer (DS/S). During the first 6 months of the EUVE mission, the scanning telescopes were used to conduct an all-sky survey consisting of short exposures ( ~ 500 s) of the entire sky between 58--740 Angstroms . These telescopes are now being used during GO observations to conduct simultaneous long exposure (typically 40+ ks) observations as part of the very successful---and publicly accessible---EUVE Right Angle Program (RAP). To date, the EUVE RAP has provided photometric and timing data on late-type stars and CVs and has been responsible for detecting dozens of previously unknown extreme ultraviolet sources, including many stars without optical counterparts. This poster presents some of the exciting results found with EUVE RAP data, along with general information about the program and instructions for submitting RAP proposals. This work is supported by NASA contract NAS5-29298.

  10. Rubber hand illusion affects joint angle perception.

    Directory of Open Access Journals (Sweden)

    Martin V Butz

    Full Text Available The Rubber Hand Illusion (RHI is a well-established experimental paradigm. It has been shown that the RHI can affect hand location estimates, arm and hand motion towards goals, the subjective visual appearance of the own hand, and the feeling of body ownership. Several studies also indicate that the peri-hand space is partially remapped around the rubber hand. Nonetheless, the question remains if and to what extent the RHI can affect the perception of other body parts. In this study we ask if the RHI can alter the perception of the elbow joint. Participants had to adjust an angular representation on a screen according to their proprioceptive perception of their own elbow joint angle. The results show that the RHI does indeed alter the elbow joint estimation, increasing the agreement with the position and orientation of the artificial hand. Thus, the results show that the brain does not only adjust the perception of the hand in body-relative space, but it also modifies the perception of other body parts. In conclusion, we propose that the brain continuously strives to maintain a consistent internal body image and that this image can be influenced by the available sensory information sources, which are mediated and mapped onto each other by means of a postural, kinematic body model.

  11. Neutron elastic scattering at very small angles

    CERN Multimedia

    2002-01-01

    This experiment will measure neutron-proton elastic scattering at very small angles and hence very small four-momentum transfer, |t|. The range of |t| depends on the incident neutron momentum of the events but the geometrical acceptance will cover the angular range 0.025 < $\\Theta_{lab}$ < 1.9 mrad. The higher figure could be extended to 8.4 mrad by changing the geometry of the experiment in a later phase. \\\\ \\\\ The neutron beam will be highly collimated and will be derived from a 400 GeV external proton beam of up to $4 \\times 10^{10}$ protons per pulse in the SPS North Area Hall 1. The hydrogen target will be gaseous, operating at 40 atm. pressure and acts as a multiwire proportional chamber to detect the recoil protons. The forward neutron will be detected and located by interaction in a neutron vertex detector and its energy measured by a conventional steel plate calorimeter. \\\\ \\\\ The experiment will cover the angular region of nucleon-nucleon scattering which is dominated by Coulomb scattering ...

  12. Phase sensitive small angle neutron scattering

    Science.gov (United States)

    Brok, Erik; Majkrzak, Charles F.; Krycka, Kathryn

    It is a well-known problem that information about the scattered wave is lost in scattering experiments because the measured quantity is the modulus squared of the complex wave function. This ''phase problem'' leads to ambiguity in determining the physical properties of the scattering sample. Small angle neutron scattering (SANS) is a useful technique for determining the structure of biomolecules, in particular proteins that cannot be crystallized and studied with x-ray crystallography. However, because the biomolecules are usually suspended in a liquid the observed scattering is an average of all possible orientations, making it difficult to obtain three dimensional structural information. In a proposed method polarized SANS and magnetic nanoparticle references attached to the sample molecules is used to obtain phase sensitive structural information and simultaneously circumvent the problem of orientational averaging (Majkrzak et al. J. Appl. Cryst. 47, 2014) If realized and perfected the technique is very promising for unambiguous determination of the three dimensional structure of biomolecules. We demonstrate the principles of our method and show the first experimental data obtained on a simple test system consisting of core shell magnetic nanoparticles.

  13. Iris melanoma invading the camerular angle

    International Nuclear Information System (INIS)

    Verona Ugando, Leticia; Landrian Iglesias, Beatriz; Padierne Gonzalez, Naysa

    2011-01-01

    Uveal melanomas are the most frequent primary uveal tumors, having an incidence of 8/1 000 000 a year in Caucasian people. Specifically, iris Melanoma represents 5 to 7 % of the uveal malignant melanomas and they may be amelanic or pigmented, generally very vascularized. An eighteen years old male patient with a history of health problems was presented, who had been seen at the Ophthalmological Emergency Service because of eye pain and sudden visual reduction in his right eye. In the physical exam, a marked ocular hypertension was confirmed as well as a 2 mm hyphema and corneal edema. These conditions were overcome with treatment and afterwards, there was observed iris tumoration invading the iridocorneal angle. Some complementary studies were carried out to search further tumors at other levels and finally a fine needle aspiration biopsy was performed. The diagnosis was amelanic Iris Melanoma invading the ciliary body. The patient was referred for surgical treatment at the National Institute of Oncology and Radiology

  14. Hadron elastic scattering at small angles

    CERN Multimedia

    2002-01-01

    This experiment is an extension of the measurements of the WA9 experiment up to the highest energies available in the North Area. It will measure the differential cross-section for hadron elastic scattering in the t-range 0.002-0.05 (GeV/c)$^{2}$ using an ionization chamber for the measurement of the energy and the angle of the recoil and a magnet-WC spectrometer to measure the momentum and direction of the forward particle. From these measurements will be obtained the ratio $\\rho$ of the real to imaginary parts of the forward elastic amplitude and the exponential slope parameter b of the hadronic amplitude at small t. The precision expected in these measurements is $\\Delta \\rho \\approx \\pm 0.01$ and $\\Delta$b $\\approx \\pm 0.2$ (GeV/c)$^{-2}$. \\\\ \\\\ The experimental programme includes: \\\\\\\\ i) measurements of $\\rho$ and b for $\\pi$p elastic scattering at incident momenta between 150 GeV/c and 300 GeV/c; \\\\ ii) measurements of $\\rho$ and b for $\\pi^{+}$p and pp elastic scattering at incident momenta between 5...

  15. Steering Angle Function Algorithm of Morphing of Residential Area

    Directory of Open Access Journals (Sweden)

    XIE Tian

    2015-07-01

    Full Text Available A residential area feature morphing method based on steering angle function is presented. To residential area with the same representation under two different scales,transforming the representation of the residential area polygon from vector coordinates to steering angle function,then using the steering angle function to match,and finding out the similarity and the differences between the residential areas under different scale to get the steering angle function of the the residential areas under any middle scale,the final,transforming the middle scale steering angle function to vector coordinates form,and get the middle shape interpolation of the the residential area polygon.Experimental results show:the residential area morphing method by using steering angle function presented can realize the continuous multi-scale representation under the premise of keeping in shape for the residential area with the rectangular boundary features.

  16. Non-contact measurement of rotation angle with solo camera

    Science.gov (United States)

    Gan, Xiaochuan; Sun, Anbin; Ye, Xin; Ma, Liqun

    2015-02-01

    For the purpose to measure a rotation angle around the axis of an object, a non-contact rotation angle measurement method based on solo camera was promoted. The intrinsic parameters of camera were calibrated using chessboard on principle of plane calibration theory. The translation matrix and rotation matrix between the object coordinate and the camera coordinate were calculated according to the relationship between the corners' position on object and their coordinates on image. Then the rotation angle between the measured object and the camera could be resolved from the rotation matrix. A precise angle dividing table (PADT) was chosen as the reference to verify the angle measurement error of this method. Test results indicated that the rotation angle measurement error of this method did not exceed +/- 0.01 degree.

  17. Vehicle Sideslip Angle Estimation Based on General Regression Neural Network

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2016-01-01

    Full Text Available Aiming at the accuracy of estimation of vehicle’s mass center sideslip angle, an estimation method of slip angle based on general regression neural network (GRNN and driver-vehicle closed-loop system has been proposed: regarding vehicle’s sideslip angle as time series mapping of yaw speed and lateral acceleration; using homogeneous design project to optimize the training samples; building the mapping relationship among sideslip angle, yaw speed, and lateral acceleration; at the same time, using experimental method to measure vehicle’s sideslip angle to verify validity of this method. Estimation results of neural network and real vehicle experiment show the same changing tendency. The mean of error is within 10% of test result’s amplitude. Results show GRNN can estimate vehicle’s sideslip angle correctly. It can offer a reference to the application of vehicle’s stability control system on vehicle’s state estimation.

  18. Osteosarcoma enters a post genomic era with in silico opportunities: Generation of the High Dimensional Database for facilitating sarcoma biology research: A report from the Children's Oncology Group and the QuadW Foundation.

    Directory of Open Access Journals (Sweden)

    Jason Glover

    Full Text Available The prospective banking of osteosarcoma tissue samples to promote research endeavors has been realized through the establishment of a nationally centralized biospecimen repository, the Children's Oncology Group (COG biospecimen bank located at the Biopathology Center (BPC/Nationwide Children's Hospital in Columbus, Ohio. Although the physical inventory of osteosarcoma biospecimens is substantive (>15,000 sample specimens, the nature of these resources remains exhaustible. Despite judicious allocation of these high-value biospecimens for conducting sarcoma-related research, a deeper understanding of osteosarcoma biology, in particular metastases, remains unrealized. In addition the identification and development of novel diagnostics and effective therapeutics remain elusive. The QuadW-COG Childhood Sarcoma Biostatistics and Annotation Office (CSBAO has developed the High Dimensional Data (HDD platform to complement the existing physical inventory and to promote in silico hypothesis testing in sarcoma biology. The HDD is a relational biologic database derived from matched osteosarcoma biospecimens in which diverse experimental readouts have been generated and digitally deposited. As proof-of-concept, we demonstrate that the HDD platform can be utilized to address previously unrealized biologic questions though the systematic juxtaposition of diverse datasets derived from shared biospecimens. The continued population of the HDD platform with high-value, high-throughput and mineable datasets allows a shared and reusable resource for researchers, both experimentalists and bioinformatics investigators, to propose and answer questions in silico that advance our understanding of osteosarcoma biology.

  19. Virtual quad zygoma implant placement using cone beam computed tomography: sufficiency of malar bone volume, intraosseous implant length, and relationship to the sinus according to the degree of alveolar bone atrophy.

    Science.gov (United States)

    Bertos Quílez, J; Guijarro-Martínez, R; Aboul-Hosn Centenero, S; Hernández-Alfaro, F

    2018-02-01

    The objective of this study was to investigate the malar bone volume and length that a zygomatic implant can engage, and the relationship to the sinus according to the degree of alveolar bone atrophy. A three-dimensional evaluation was performed using cone beam computed tomography scans from 23 patients with a totally edentulous maxilla; quad zygoma implants were virtually placed. The predictor variable was the amount of malar bone volume and length that a zygomatic implant can engage. The primary outcome variable was the relationship to the sinus according to the degree of alveolar bone atrophy. Other variables were the residual alveolar bone height to the floor of the sinus and the nasal cavity. The mean volume of malar bone engaged in this sample of 92 zygomatic implants was 0.19±0.06cm 3 . The implant had an extrasinus path in 60.9% of cases, a parasinus path in 25%, and an intrasinus path in 14.1%. The results suggest that the average volume of malar bone engaged by a zygomatic implant is constant regardless of implant position and the degree of alveolar bone atrophy. As alveolar atrophy increases, the trajectory of the implant becomes more parasinus and intrasinus. The examiners were able to find enough bone to adequately distribute the implants in all cases. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  20. Comparison of Anterior Segment-Optical Coherence Tomography Parameters in Phacomorphic Angle Closure and Acute Angle Closure Eyes.

    Science.gov (United States)

    Moghimi, Sasan; Ramezani, Farshid; He, Mingguang; Coleman, Anne L; Lin, Shan C

    2015-12-01

    The purpose of this study is to compare anterior segment-optical coherence tomography (AS-OCT) parameters in phacomorphic angle closure and acute primary angle closure (APAC) eyes. In this cross-sectional case series, a total of 134 patients with phacomorphic angle closure (28 eyes) or APAC (54 eyes), as well as normal control subjects (52 eyes), were enrolled. Patients underwent AS-OCT imaging and A-scan biometry of both eyes. Anterior chamber depth (ACD), anterior chamber area (ACA), iris thickness (IT), iris curvature, lens vault (LV), anterior vault (AV), and angle parameters including angle opening distance (AOD 500 and AOD750) and trabecular iris space area (TISA500 and TISA750) were measured in qualified images using the Zhongshan Angle Assessment Program and compared among eyes with phacomorphic angle closure, APAC, and normal control subjects. Phacomorphic angle closure and APAC eyes had smaller AOD, ACD, ACA, ACW, AV, and posterior corneal arc length and greater LV than normal controls (P APAC eyes: ACD 1042 μm (OR,12.12; P APAC eyes. In multivariate analysis, ACD, LV, AOD500, and axial length could significantly distinguish the two entities. Ocular biometric parameters can differentiate phacomorphic angle closure from APAC eyes. Shallower ACD and greater LV, axial length, and ACA are the main parameters that distinguish phacomorphic angle closure from APAC.

  1. Ultrasound biomicroscopic features associated with angle closure in fellow eyes of acute primary angle closure after laser iridotomy.

    Science.gov (United States)

    Yao, Bao-qun; Wu, Ling-ling; Zhang, Chun; Wang, Xin

    2009-03-01

    To investigate the frequency of appositional angle closure and related anatomic characteristics in fellow eyes of Chinese subjects with acute primary angle closure (APAC) after laser peripheral iridotomy (LPI). Cross-sectional study. Consecutive subjects with APAC presenting from April 2006 to September 2006 at the Glaucoma Service of Peking University Eye Center, Peking University Third Hospital. Under dark conditions, fellow eyes were divided into 2 groups based on the detection of appositional angle closure by ultrasound biomicroscopy (UBM). For all subjects, UBM parameters were measured to evaluate the different anatomic features between the 2 groups. Darkroom provocative tests (DRPTs) and gonioscopy were performed to investigate the relationship between angle closure and intraocular pressure. Central anterior chamber depth (ACD); angle opening distance(500) (AOD(500)); angle recess area(750) (ARA(750)); trabecular-iris angle (T-I angle); trabecular-ciliary process distance (TCPD); peripheral iris thickness (IT(1)); iris-zonule distance (IZD); and the position of the iris insertion. Thirty-four post-LPI fellow eyes of 34 patients with APAC (8 men, 26 women; mean +/- standard deviation age 66.3+/-7.2 years, range 54-83) were included. Peripheral anterior synechiae (PAS) were not observed in any subject. Appositional angle closure was observed in at least 1 quadrant in 13 (38.2%) of the 34 patients. Compared with eyes without appositional closure, eyes with appositional closure showed significantly lower AOD(500), ARA(750), and T-I angle in 4 quadrants; shorter TCPD in the inferior and temporal quadrants; and thicker IT(1) in the superior and nasal quadrants (PAPAC showed appositional angle closure after LPI. The anatomic findings indicate a narrower angle, a more anterior position of the ciliary body, and a thicker peripheral iris in fellow eyes of APAC after LPI may be associated with an increased risk for progressive angle closure.

  2. Rotating Shaft Tilt Angle Measurement Using an Inclinometer

    OpenAIRE

    Luo Jun; Wang Zhiqian; Shen Chengwu; Wen Zhuoman; Liu Shaojin; Cai Sheng; Li Jianrong

    2015-01-01

    This paper describes a novel measurement method to accurately measure the rotating shaft tilt angle of rotating machine for alignment or compensation using a dual-axis inclinometer. A model of the rotating shaft tilt angle measurement is established using a dual-axis inclinometer based on the designed mechanical structure, and the calculation equation between the rotating shaft tilt angle and the inclinometer axes outputs is derived under the condition that the inclinometer axes are perpendic...

  3. Angle Dependent Optics of Plasmonic Core-Shell Nanoparticles

    Science.gov (United States)

    2018-02-21

    function of spherical co-ordinates: azimuthal and polar angles. Absorption, scattering and emission of light from nanoparticles, especially when they are...placed on a substrate, can drastically depend on angle of excitation and angle of scattering/ emission . Such particle-substrate coupling can...V’ antenna with the Raman marker molecule nile blue chloride. Typical SERS spectra of nile blue from a ‘V’ antenna under different polarizations (0

  4. Glancing angle x-ray studies of oxide films

    International Nuclear Information System (INIS)

    Davenport, A.J.; Isaacs, H.S.

    1989-01-01

    High brightness synchrotron radiation incident at glancing angles has been used to study inhibiting species present in low concentrations in oxide films on aluminum. Glancing incident angle fluorescence measurements give surface-sensitive information on the valence state of elements from the shape of the x-ray absorption edge. Angle-resolved measurements show the depth distribution of the species present. 15 refs., 4 figs

  5. Small-angle neutron scattering technique in liquid crystal studies

    International Nuclear Information System (INIS)

    Shahidan Radiman

    2005-01-01

    The following topics discussed: general principles of SAS (Small-angle Neutron Scattering), liquid crystals, nanoparticle templating on liquid crystals, examples of SAS results, prospects of this studies

  6. Changes in the foot angle after calcaneal fractures

    International Nuclear Information System (INIS)

    Frahm, R.; Fritz, H.; Drescher, E.

    1989-01-01

    Forty fractured calcanei (13 without and 27 with involvement of the joint) were examined by CT and the angle of the hind foot measured. Following a typical compression fracture there is a negative calcaneusvalgus angle, i.e. varus deformity of the tuberosity fragment. The sustentaculum angle is increased. There are changes in the talo-calcaneal and calcaneo-cuboidal angles. The length ratio of calcaneus to talus is reduced. Reproducible measurements make it possible to compare the results of operative correction and of changes in shape following conservative treatment, e.g. during weight-bearing. (orig.) [de

  7. Flow tilt angles near forest edges - Part 1: Sonic anemometry

    DEFF Research Database (Denmark)

    Dellwik, Ebba; Mann, Jakob; Larsen, Klaus Steenberg

    2010-01-01

    An analysis of flow tilt angles from a fetch-limited beech forest site with clearings is presented in the context of vertical advection of carbon dioxide. Flow angles and vertical velocities from two sonic anemometers by different manufacturers were analyzed. Instead of using rotations, where zero...... distortion and vertical alignment, it was only possible to a limited extent to relate sonic anemometer flow tilt angles to upwind forest edges, but the results by the lidar indicated that an internal boundary layer affect flow tilt angles at 21m above the forest. This is in accordance with earlier studies...

  8. Beam-beam collisions and crossing angles in RHIC

    International Nuclear Information System (INIS)

    Peggs, S.

    1999-01-01

    This paper evaluates the strength of head on and parasitic beam-beam collisions in RHIC when the crossing angle is zero. A non-zero crossing angle is not required in normal operation with 120 bunches, thanks to the early separation of the two beams. The RHIC lattice is shown to easily accommodate even conservatively large crossing angles, for example in beam dynamics studies, or in future operational upgrades to as many as 360 bunches per ring. A modest loss in luminosity is incurred when gold ions collide at an angle after 10 hours of storage

  9. The wave vane - A device to measure the breaker angle

    Digital Repository Service at National Institute of Oceanography (India)

    Chandramohan, P.; Nayak, B.U.; Anand, N.M.

    with the shoreline at the wave vane is equal to the breaker angle as the wave vane is installed very close to breaker zone. Repeating the procedure, the breaker angles for a required duration can be estimated. FIELD TEST A 4 km long beach near Karwar on the west... in Table 1. Ob- servations on breaker angles were made for 20 minutes duration every day. The average breaker angle computed based on the 20 minute observation is presented in Table 1. A directional wave rider buoy was deployed at 16 m water depth...

  10. Contact angle distribution of particles at fluid interfaces.

    Science.gov (United States)

    Snoeyink, Craig; Barman, Sourav; Christopher, Gordon F

    2015-01-27

    Recent measurements have implied a distribution of interfacially adsorbed particles' contact angles; however, it has been impossible to measure statistically significant numbers for these contact angles noninvasively in situ. Using a new microscopy method that allows nanometer-scale resolution of particle's 3D positions on an interface, we have measured the contact angles for thousands of latex particles at an oil/water interface. Furthermore, these measurements are dynamic, allowing the observation of the particle contact angle with high temporal resolution, resulting in hundreds of thousands of individual contact angle measurements. The contact angle has been found to fit a normal distribution with a standard deviation of 19.3°, which is much larger than previously recorded. Furthermore, the technique used allows the effect of measurement error, constrained interfacial diffusion, and particle property variation on the contact angle distribution to be individually evaluated. Because of the ability to measure the contact angle noninvasively, the results provide previously unobtainable, unique data on the dynamics and distribution of the adsorbed particles' contact angle.

  11. Tibial and fibular angles in homozygous sickle cell disease

    International Nuclear Information System (INIS)

    Akamaguna, A.I.; Odita, J.C.; Ugbodaga, C.I.; Okafor, L.A.

    1986-01-01

    Measurements of the tibial and fibular angles made on ankle radiographs of 34 patients with sickle cell disease were compared with those of 36 normal Nigerians. Widening of the fibular angle, which is an indication of tibiotalar slant, was demonstrated in about 79% of sickle cell disease patients. By using fibular angle measurements as an objective method of assessing subtle tibiotalar slant, it is concluded that the incidence of this deformity is much higher among sickle cell disease patients than previously reported. The mean values of tibial and fibular angles in normal Nigerians are higher than has been reported amongst Caucasians. (orig.)

  12. Characterizing the combinatorial beam angle selection problem

    International Nuclear Information System (INIS)

    Bangert, Mark; Ziegenhein, Peter; Oelfke, Uwe

    2012-01-01

    The beam angle selection (BAS) problem in intensity-modulated radiation therapy is often interpreted as a combinatorial optimization problem, i.e. finding the best combination of η beams in a discrete set of candidate beams. It is well established that the combinatorial BAS problem may be solved efficiently with metaheuristics such as simulated annealing or genetic algorithms. However, the underlying parameters of the optimization process, such as the inclusion of non-coplanar candidate beams, the angular resolution in the space of candidate beams, and the number of evaluated beam ensembles as well as the relative performance of different metaheuristics have not yet been systematically investigated. We study these open questions in a meta-analysis of four strategies for combinatorial optimization in order to provide a reference for future research related to the BAS problem in intensity-modulated radiation therapy treatment planning. We introduce a high-performance inverse planning engine for BAS. It performs a full fluence optimization for ≈3600 treatment plans per hour while handling up to 50 GB of dose influence data (≈1400 candidate beams). For three head and neck patients, we compare the relative performance of a genetic, a cross-entropy, a simulated annealing and a naive iterative algorithm. The selection of ensembles with 5, 7, 9 and 11 beams considering either only coplanar or all feasible candidate beams is studied for an angular resolution of 5°, 10°, 15° and 20° in the space of candidate beams. The impact of different convergence criteria is investigated in comparison to a fixed termination after the evaluation of 10 000 beam ensembles. In total, our simulations comprise a full fluence optimization for about 3000 000 treatment plans. All four combinatorial BAS strategies yield significant improvements of the objective function value and of the corresponding dose distributions compared to standard beam configurations with equi

  13. Angle Class II correction with MARA appliance

    Directory of Open Access Journals (Sweden)

    Kelly Chiqueto

    2013-02-01

    Full Text Available OBJECTIVE: To assess the effects produced by the MARA appliance in the treatment of Angle's Class II, division 1 malocclusion. METHODS: The sample consisted of 44 young patients divided into two groups: The MARA Group, with initial mean age of 11.99 years, treated with the MARA appliance for an average period of 1.11 years, and the Control Group, with initial mean age of 11.63 years, monitored for a mean period of 1.18 years with no treatment. Lateral cephalograms were used to compare the groups using cephalometric variables in the initial and final phases. For these comparisons, Student's t test was employed. RESULTS: MARA appliance produced the following effects: Maxillary growth restriction, no change in mandibular development, improvement in maxillomandibular relationship, increased lower anterior facial height and counterclockwise rotation of the functional occlusal plane. In the upper arch, the incisors moved lingually and retruded, while the molars moved distally and tipped distally. In the lower arch, the incisors proclined and protruded, whereas the molars mesialized and tipped mesially. Finally, there was a significant reduction in overbite and overjet, with an obvious improvement in molar relationship. CONCLUSIONS: It was concluded that the MARA appliance proved effective in correcting Angle's Class II, division 1 malocclusion while inducing skeletal changes and particularly dental changes.OBJETIVO: avaliar os efeitos proporcionados pelo aparelho MARA no tratamento da má oclusão de Classe II, 1ª divisão. MÉTODOS: utilizou-se uma amostra de 44 jovens, divididos em dois grupos - Grupo MARA, com idade inicial média de 11,99 anos e tratado com o aparelho MARA por um período médio de 1,11 ano; e Grupo Controle, com idade inicial média de 11,63 ano e observado por um período médio de 1,18 ano, sem nenhum tratamento. Utilizou-se as telerradiografias em norma lateral para comparar os grupos quanto às variáveis cefalométricas das

  14. Characterizing the combinatorial beam angle selection problem

    Science.gov (United States)

    Bangert, Mark; Ziegenhein, Peter; Oelfke, Uwe

    2012-10-01

    The beam angle selection (BAS) problem in intensity-modulated radiation therapy is often interpreted as a combinatorial optimization problem, i.e. finding the best combination of η beams in a discrete set of candidate beams. It is well established that the combinatorial BAS problem may be solved efficiently with metaheuristics such as simulated annealing or genetic algorithms. However, the underlying parameters of the optimization process, such as the inclusion of non-coplanar candidate beams, the angular resolution in the space of candidate beams, and the number of evaluated beam ensembles as well as the relative performance of different metaheuristics have not yet been systematically investigated. We study these open questions in a meta-analysis of four strategies for combinatorial optimization in order to provide a reference for future research related to the BAS problem in intensity-modulated radiation therapy treatment planning. We introduce a high-performance inverse planning engine for BAS. It performs a full fluence optimization for ≈3600 treatment plans per hour while handling up to 50 GB of dose influence data (≈1400 candidate beams). For three head and neck patients, we compare the relative performance of a genetic, a cross-entropy, a simulated annealing and a naive iterative algorithm. The selection of ensembles with 5, 7, 9 and 11 beams considering either only coplanar or all feasible candidate beams is studied for an angular resolution of 5°, 10°, 15° and 20° in the space of candidate beams. The impact of different convergence criteria is investigated in comparison to a fixed termination after the evaluation of 10 000 beam ensembles. In total, our simulations comprise a full fluence optimization for about 3000 000 treatment plans. All four combinatorial BAS strategies yield significant improvements of the objective function value and of the corresponding dose distributions compared to standard beam configurations with equi

  15. Simulation of Canopy Leaf Inclination Angle in Rice

    Directory of Open Access Journals (Sweden)

    Xiao-cui ZHANG

    2013-11-01

    Full Text Available A leaf inclination angle distribution model, which is applicable to simulate leaf inclination angle distribution in six heights of layered canopy at different growth stages, was established by component factors affecting plant type in rice. The accuracy of the simulation results was validated by measured values from a field experiment. The coefficient of determination (R2 and the root mean square error (RMSE between the simulated and measured values were 0.9472 and 3.93%, respectively. The simulation results showed that the distribution of leaf inclination angles differed among the three plant types. The leaf inclination angles were larger in the compact variety Liangyoupeijiu with erect leaves than in the loose variety Shanyou 63 with droopy leaves and the intermediate variety Liangyou Y06. The leaf inclination angles were distributed in the lower range in Shanyou 63, which matched up with field measurements. The distribution of leaf inclination angles in the same variety changed throughout the seven growth stages. The leaf inclination angles enlarged gradually from transplanting to booting. During the post-booting period, the leaf inclination angle increased in Shanyou 63 and Liangyou Y06, but changed little in Liangyoupeijiu. At every growth stage of each variety, canopy leaf inclination angle distribution on the six heights of canopy layers was variable. As canopy height increased, the layered leaf area index (LAI decreased in all the three plant types. However, while the leaf inclination angles showed little change in Liangyoupeijiu, they became larger in Shanyou 63 but smaller in Liangyou Y06. The simulation results used in the constructed model were very similar to the actual measurement values. The model provides a method for estimating canopy leaf inclination angle distribution in rice production.

  16. Plateau iris in Japanese patients with primary angle closure and primary angle closure glaucoma.

    Science.gov (United States)

    Mizoguchi, Takanori; Ozaki, Mineo; Wakiyama, Harumi; Ogino, Nobuchika

    2015-01-01

    To determine the prevalence of plateau iris in Japanese patients with primary angle closure (PAC) and primary angle closure glaucoma (PACG) and analyze the biometric parameters in patients with plateau iris using ultrasound biomicroscopy (UBM). In this cross-sectional observational study, subjects aged >50 years with PAC and PACG who had previously undergone a patent laser peripheral iridotomy underwent UBM in one eye. UBM images were qualitatively analyzed using standardized criteria. Plateau iris in a quadrant was defined by anteriorly directed ciliary body, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact. At least two quadrants had to fulfill these UBM criteria for an eye to be classified as having plateau iris. A-scan biometry was used to measure anterior segment parameters. Ninety-one subjects with PAC (58 subjects) or PACG (33 subjects) and 68 normal controls were recruited. The mean (standard deviation) ages of PAC and PACG patients and normal controls were 73.5 (6.2) and 72.6 (7.3), respectively. Based on UBM criteria, plateau iris was found in 16 eyes (17.6%) of 91 eyes. In these 16 eyes, quadrant-wise analysis showed ten eyes (62.5%) had plateau iris in two quadrants; four eyes (25%) had plateau iris in three quadrants; and two eyes (12.5%) had plateau iris in four quadrants. Anterior chamber depth, lens thickness, axial length, lens position, and relative lens position were not statistically significant between the group having plateau iris and that not having plateau iris, respectively. Approximately 20% of Japanese subjects with PAC and PACG with a patent laser peripheral iridotomy were found to have plateau iris on UBM. No morphological difference was noted in the anterior segment of the eye between those with or without plateau iris.

  17. Plateau iris in Japanese patients with primary angle closure and primary angle closure glaucoma

    Directory of Open Access Journals (Sweden)

    Mizoguchi T

    2015-06-01

    Full Text Available Takanori Mizoguchi,1 Mineo Ozaki,2,3 Harumi Wakiyama,1,4 Nobuchika Ogino1,51Mizoguchi Eye Clinic, Nagasaki, Japan; 2Ozaki Eye Clinic Miyazaki, Japan; 3Department of Ophthalmology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan; 4The Japanese Red Cross Nagasaki Genbaku Hospital, Nagasaki, Japan; 5Nishigaki Eye Clinic, Nagoya, JapanPurpose: To determine the prevalence of plateau iris in Japanese patients with primary angle closure (PAC and primary angle closure glaucoma (PACG and analyze the biometric parameters in patients with plateau iris using ultrasound biomicroscopy (UBM.Methods: In this cross-sectional observational study, subjects aged >50 years with PAC and PACG who had previously undergone a patent laser peripheral iridotomy underwent UBM in one eye. UBM images were qualitatively analyzed using standardized criteria. Plateau iris in a quadrant was defined by anteriorly directed ciliary body, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact. At least two quadrants had to fulfill these UBM criteria for an eye to be classified as having plateau iris. A-scan biometry was used to measure anterior segment parameters.Results: Ninety-one subjects with PAC (58 subjects or PACG (33 subjects and 68 normal controls were recruited. The mean (standard deviation ages of PAC and PACG patients and normal controls were 73.5 (6.2 and 72.6 (7.3, respectively. Based on UBM criteria, plateau iris was found in 16 eyes (17.6% of 91 eyes. In these 16 eyes, quadrant-wise analysis showed ten eyes (62.5% had plateau iris in two quadrants; four eyes (25% had plateau iris in three quadrants; and two eyes (12.5% had plateau iris in four quadrants. Anterior chamber depth, lens thickness, axial length, lens position, and relative lens position were not statistically significant between the group having plateau iris and that not having plateau iris

  18. Investigation of Polarimetric SAR Data Acquired at Multiple Incidence Angles

    DEFF Research Database (Denmark)

    Svendsen, Morten Thougaard; Skriver, Henning; Thomsen, A.

    1998-01-01

    The dependence of different polarimetric parameters on the incidence angles in the range of 30° to 60° is investigated for a number of different crops using airborne SAR data. The purpose of the investigation is to determine the effect of the variation of incidence angle within a SAR image when...

  19. Physiological response to angling of Africa's premier freshwater ...

    African Journals Online (AJOL)

    Blood plasma was analysed for glucose, cortisol and lactate concentrations to assess the effects of angling duration, fish size and fish condition. Larger fish were angled for a longer duration. Plasma glucose concentrations decreased with greater lactate concentrations, an indication of the aerobic and anaerobic work done ...

  20. Contact angle hysteresis: a review of fundamentals and applications

    NARCIS (Netherlands)

    Eral, Burak; 't Mannetje, Dieter; Oh, J.M.

    2013-01-01

    Contact angle hysteresis is an important physical phenomenon. It is omnipresent in nature and also plays a crucial role in various industrial processes. Despite its relevance, there is a lack of consensus on how to incorporate a description of contact angle hysteresis into physical models. To

  1. Normal values of knee angle, intercondylar and intermalleolar ...

    African Journals Online (AJOL)

    There is little data on the range of variation of knee angle, intermalleolar and intercondylar distances in African children. Such measurements are needed to assist determining whether a child legs are normal or not. Knee angle intermalleolar and intercondylar distances were measured in 2166 Nigerian children aged one ...

  2. Escape angles in bulk chi((2)) soliton interactions

    DEFF Research Database (Denmark)

    Johansen, Steffen Kjær; Bang, Ole; Sørensen, Mads Peter

    2002-01-01

    We develop a theory for nonplanar interaction between two identical type I spatial solitons propagating at opposite, but arbitrary transverse angles in quadratic nonlinear (or so-called chi((2))) bulk, media. We predict quantitatively the outwards escape angle, below which the solitons turn around...

  3. Small angle neutron scattering from nanometer grain sized materials

    Science.gov (United States)

    Epperson, J. E.; Siegel, R. W.

    1991-11-01

    Small angle neutron scattering has been utilized, along with a number of complementary characterization methods suitable to the nanometer size scale, to investigate the structures of cluster-assembled nanophase materials. Results of these investigations are described and problems and opportunities in using small angle scattering for elucidating nanostructures are discussed.

  4. Small angle polarised neutron scattering investigation of magnetic nanoparticles

    International Nuclear Information System (INIS)

    Bergenti, I.; Deriu, A.; Savini, L.; Bonetti, E.; Spizzo, F.; Hoell, H.

    2003-01-01

    Small angle scattering of polarised neutron (SANSPOL) is a powerful technique for the determination of magnetisation, density and compositional profiles of nanostructured particles. We present here some examples of the magnetic profile determination using the SANSPOL technique and we discuss in detail its advantage with respect to the conventional small angle neutron scattering approach

  5. An assessment of recreational bank angling in the Free State ...

    African Journals Online (AJOL)

    Recreational angling is an important form of utilisation of inland fisheries in South Africa but there is little information on this sector. The objective of this study was to provide an assessment of recreational bank angling in the Free State Province using licence sale and tournament data. During 2013 and 2014, 8 256 and 7 ...

  6. Determination of the Optimum Collector Angle for Composite Solar ...

    African Journals Online (AJOL)

    A model for predicting solar radiation available at any given time in the inhabited area in Ilorin was developed. From the equation developed, the optimum tilt angle of the collector due south was carried out. The optimum angle of tilt of the collector and the orientation are dependent on the month of the year and the location ...

  7. Radiological assessment of the femoral bicondylar angle in a ...

    African Journals Online (AJOL)

    Background: Femoral bicondylar angle is the angle between the diaphysis of the femur and a line perpendicular to the infracondylar plane. It is indispensable in bipedal locomotion as it serves to place the knee and foot under the body's center of gravity during the single support phase of gait. Although the mechanism for the ...

  8. Solar electricity potentials and optimal angles for mounting solar ...

    African Journals Online (AJOL)

    The need for harnessing solar energy using solar panels mounted at optimal inclination angles in the six geopolitical zones of Nigeria is presented. The optimal angle for mounting solar panels as presented by Photovoltaic Geographic Information System (PVGIS) ranges from 11º to 14º in the Southern zone and 13º to 16º ...

  9. 46 CFR 58.01-40 - Machinery, angles of inclination.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Machinery, angles of inclination. 58.01-40 Section 58.01-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-40 Machinery, angles of inclination. (a) Propulsion machinery and all auxiliary...

  10. Gradient angle estimation by uniform directional simulation on a cone

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager

    1997-01-01

    approximation to a locally most central limit state point. Moreover, the estimated angle can be used to correct the geometric reliability index.\\bfseries Keywords: Directional simulation, effectivity factor, gradient angle estimation, maximum likelihood, model-correction-factor method, Monte Carlo simulation...

  11. A new uncertainty relation for angular momentum and angle

    International Nuclear Information System (INIS)

    Kranold, H.U.

    1984-01-01

    An uncertainty relation of the form ΔL 2 ΔSo >=sup(h/2π)/sub(2) is derived for angular momentum and angle. The non-linear operator So measures angles and has a simple interpretation. Subject to very general conditions of rotational invariance the above relation is unique. Radial momentum is not quantized

  12. A cephalometric assessment of the nasolabial angle of an adult ...

    African Journals Online (AJOL)

    Objective: One of the most important components of orthodontic diagnosis and treatment planning is an evaluation of the patient's soft tissue profile. An assessment of the nasolabial angle is a vital component of this evaluation. The purpose of this study was to establish norms for the nasolabial angle of an adult Nigerian ...

  13. A gallery approach for off-angle iris recognition

    Science.gov (United States)

    Karakaya, Mahmut; Yoldash, Rashiduddin; Boehnen, Christopher

    2015-05-01

    It has been proven that hamming distance score between frontal and off-angle iris images of same eye differs in iris recognition system. The distinction of hamming distance score is caused by many factors such as image acquisition angle, occlusion, pupil dilation, and limbus effect. In this paper, we first study the effect of the angle variations between iris plane and the image acquisition systems. We present how hamming distance changes for different off-angle iris images even if they are coming from the same iris. We observe that increment in acquisition angle of compared iris images causes the increment in hamming distance. Second, we propose a new technique in off-angle iris recognition system that includes creating a gallery of different off-angle iris images (such as, 0, 10, 20, 30, 40, and 50 degrees) and comparing each probe image with these gallery images. We will show the accuracy of the gallery approach for off-angle iris recognition.

  14. Presentation of Primary Open Angle Glaucoma (POAG) at Lions ...

    African Journals Online (AJOL)

    Objective Primary open angle glaucoma (POAG) is the most common type of glaucoma in Africa. We carried out a study to determine the clinical presentation pattern of patients with primary open angle glaucoma (POAG) at a tertiary hospital in Malawi. Design A cross-sectional study. Setting Lions Sight First Eye Hospital—a ...

  15. Engineering sidewall angles of silica-on-silicon waveguides

    DEFF Research Database (Denmark)

    Haiyan, Ou

    2004-01-01

    Burned photoresist is used as etch mask when producing silica-onsilicon waveguides. The sidewall angle of the optical glass waveguides is engineered by varying photoresist thickness and etch selectivity. The principle for the formation of the angles is introduced and very promising experimental...

  16. Angle-domain common-image gathers from anisotropic Gaussian ...

    Indian Academy of Sciences (India)

    An approach for extracting angle-domain common-image gathers (ADCIGs) from anisotropic Gaussian beam prestack depth migration (GB-PSDM) is presented in this paper. The propagation angle is calcu- lated in the process of migration using the real-value traveltime information of Gaussian beam. Based on the above ...

  17. A Novel Monopulse Angle Estimation Method for Wideband LFM Radars

    Directory of Open Access Journals (Sweden)

    Yi-Xiong Zhang

    2016-06-01

    Full Text Available Traditional monopulse angle estimations are mainly based on phase comparison and amplitude comparison methods, which are commonly adopted in narrowband radars. In modern radar systems, wideband radars are becoming more and more important, while the angle estimation for wideband signals is little studied in previous works. As noise in wideband radars has larger bandwidth than narrowband radars, the challenge lies in the accumulation of energy from the high resolution range profile (HRRP of monopulse. In wideband radars, linear frequency modulated (LFM signals are frequently utilized. In this paper, we investigate the monopulse angle estimation problem for wideband LFM signals. To accumulate the energy of the received echo signals from different scatterers of a target, we propose utilizing a cross-correlation operation, which can achieve a good performance in low signal-to-noise ratio (SNR conditions. In the proposed algorithm, the problem of angle estimation is converted to estimating the frequency of the cross-correlation function (CCF. Experimental results demonstrate the similar performance of the proposed algorithm compared with the traditional amplitude comparison method. It means that the proposed method for angle estimation can be adopted. When adopting the proposed method, future radars may only need wideband signals for both tracking and imaging, which can greatly increase the data rate and strengthen the capability of anti-jamming. More importantly, the estimated angle will not become ambiguous under an arbitrary angle, which can significantly extend the estimated angle range in wideband radars.

  18. A 'conveyor belt' model for the dynamic contact angle

    International Nuclear Information System (INIS)

    Volpe C, Della; Siboni, S

    2011-01-01

    The familiar Young contact angle measurement of a liquid at equilibrium on a solid is a fundamental aspect of capillary phenomena. But in the real world it is not so easy to observe it. This is due to the roughness and/or heterogeneity of real surfaces, which typically are not perfectly planar and chemically homogeneous. What can be easily detected, and in a repeatable way, are advancing and receding contact angles. In this paper, we discuss a simple model which accounts for the onset of advancing and receding contact angles measured by the Wilhelmy microbalance, one of the most powerful techniques for contact angle measurements. The model also explains the experimental observation that advancing and receding contact angles become closer to each other when the system is gently 'shaken', by supplying mechanical energy in an appropriate way. The model may be pedagogically useful in introducing students and teachers to aspects of capillary phenomena which are not usually discussed in basic physics courses.

  19. Nonlinearity in the effect of an inhomogeneous Hall angle

    Science.gov (United States)

    Koon, Daniel W.

    2007-03-01

    The differential equation for the electric potential in a conducting material with an inhomogeneous Hall angle is extended to the large-field limit. This equation is solved for a square specimen, using a successive over-relaxation [SOR] technique for matrices of up to 101x101 size, and the Hall weighting function -- the effect of local pointlike perturbations on the measured Hall angle -- is calculated as both the unperturbed Hall angle, θH, and the perturbation, δθH, exceed the linear, small angle limit. Preliminary results show that the Hall angle varies by no more than 5% if both | θH |<1 and | δθH |<1. Thus, previously calculated results for the Hall weighting function can be used for most materials in all but the most extreme magnetic fields.

  20. Does Sacrococcygeal Angle Play a Role on Pilonidal Sinus Etiology?

    Directory of Open Access Journals (Sweden)

    Ramazan Eryilmaz

    2015-01-01

    Full Text Available The predisposing factors for the development of sacrococcygeal pilonidal disease (SPD still remain undetermined. Here, we investigate the sacrococcygeal angle as a possible predisposing factor for the development of disease. Consecutive male patients admitted to our clinic with the diagnosis of SPD were included. Sex, age and BMI matched healthy controls without SPD were enrolled to the study. The predefined sacrococcygeal angles of patients and controls were measured on lateral pelvic radiographs by a single experienced radiologist. Thirty patients were included in each group. Sacrococcygeal angles of patients and control group were measured as 37.3 ± 14.5 and 36.81 ± 10.23 in patients and controls, respectively. The difference with respect to sacrococcygeal angle was not statistically significant between two groups. Sacrococcygeal angle which is the main skeletal determinant of intergluteal sulcus is not a predisposing factor for the development of sacrococcygeal pilonidal disease.

  1. Neutron small angle scattering of irradiated aluminium-silicon alloys

    International Nuclear Information System (INIS)

    Kostorz, G.

    1976-01-01

    Technically pure aluminium and aluminium-silicon alloys (0.43, 0.83 and 1.2% Si, also containing 0.11 to 0.14 at. % Fe) were investigated by slow neutron small angle scattering after irradiation with fast neutrons at low temperatures. Different irradiation levels, ageing at room temperature and at 60/70 0 C had no measurable effect upon small angle scattering cross-sections. From the experimental precision upper limit for the amount of Si involved in clustering after irradiation can be given. The observed small angle scattering shows a strong dependence on scattering angles and is attributed to large precipitates of Al 12 Fe 3 Si. A surface layer on the as-received samples is identified as another source of low-intensity small angle scattering. (orig.) [de

  2. Phacoemulsification treatment of subjects with acute primary angle closure and chronic primary angle-closure glaucoma.

    Science.gov (United States)

    Zhuo, Ye-Hong; Wang, Mei; Li, Ying; Hao, Yuan-Tao; Lin, Min-Kai; Fang, Min; Ge, Jian

    2009-12-01

    To investigate and compare the effects of phacoemulsification as an initial procedure to control intraocular pressure (IOP) in eyes with acute primary angle closure (APAC) and chronic primary angle-closure glaucoma (CPACG) with coexisting cataracts and peripheral anterior synechiae (PAS) of greater than 180 degrees. Prospective, cross-sectional study. Thirteen patients (13 eyes) with APAC and 10 patients (10 eyes) with CPACG were enrolled in the study. IOP control in the 2 groups was compared at final follow-up. Other outcome measures included visual acuity, anterior chamber depth, gonioscopic appearance, and complications. The postoperative IOP was reduced in both the APAC and CPACG groups. As assessed at last follow-up (median 6 mo), IOP in the APAC group was significantly lower than that in the CPACG group. The absolute success rate was 100% in the APAC group and 80% in the CPACG group. The number of hypotensive medications decreased in both APAC and CPACG group. The postoperative degree of PAS was relieved in 11 of 12 eyes with APAC and 5 of 9 eyes with CPACG. Initial phacoemulsification performed to provide short-term control of IOP is more efficacious in patients with APAC than in those with CPACG, especially when PAS is greater than 180 degrees.

  3. Deep learning methods for protein torsion angle prediction.

    Science.gov (United States)

    Li, Haiou; Hou, Jie; Adhikari, Badri; Lyu, Qiang; Cheng, Jianlin

    2017-09-18

    Deep learning is one of the most powerful machine learning methods that has achieved the state-of-the-art performance in many domains. Since deep learning was introduced to the field of bioinformatics in 2012, it has achieved success in a number of areas such as protein residue-residue contact prediction, secondary structure prediction, and fold recognition. In this work, we developed deep learning methods to improve the prediction of torsion (dihedral) angles of proteins. We design four different deep learning architectures to predict protein torsion angles. The architectures including deep neural network (DNN) and deep restricted Boltzmann machine (DRBN), deep recurrent neural network (DRNN) and deep recurrent restricted Boltzmann machine (DReRBM) since the protein torsion angle prediction is a sequence related problem. In addition to existing protein features, two new features (predicted residue contact number and the error distribution of torsion angles extracted from sequence fragments) are used as input to each of the four deep learning architectures to predict phi and psi angles of protein backbone. The mean absolute error (MAE) of phi and psi angles predicted by DRNN, DReRBM, DRBM and DNN is about 20-21° and 29-30° on an independent dataset. The MAE of phi angle is comparable to the existing methods, but the MAE of psi angle is 29°, 2° lower than the existing methods. On the latest CASP12 targets, our methods also achieved the performance better than or comparable to a state-of-the art method. Our experiment demonstrates that deep learning is a valuable method for predicting protein torsion angles. The deep recurrent network architecture performs slightly better than deep feed-forward architecture, and the predicted residue contact number and the error distribution of torsion angles extracted from sequence fragments are useful features for improving prediction accuracy.

  4. [Diagnostic value of Blumensaat angle for anterior cruciate ligament injury].

    Science.gov (United States)

    Cheng, Xiang-Yun; Feng, Jiang-Feng; Lu, Yan-Hui; Zhao, Yong-Liang; Yang, Zi-Quan

    2017-08-25

    The receiver operator characteristic(ROC) curve was used to determine the best Blumensaat angle for the diagnosis of anterior cruciate ligament injury, so as to objectively evaluate the diagnostic value of Blumensaat angle for anterior cruciate ligament injury. Total 167 patients who had knee arthroscopic treatment in a hospital from January 2015 to January 2016 were retrospectively studied, and the patients' age, gender, left and right limb condition were recorded. The patients were divided into two groups according to Blumensaat angle measured on the MRI: group A(Blumensaat angle0°). The ROC curve was drawn from the statistical data of the group B to get the best critical value of the anterior cruciate ligament injury when the Blumensaat angle was more than 0°. According to the best critical value obtained by ROC curve, the coincidence rate of the total sample was obtained. There were no significant differences in patients' age, gender, and affected limbs. There were 51 patients in group A, in which 49 patients were diagnosed as anterior cruciate injury under arthroscopy(gold standard for diagnosis of anterior cruciate ligament injury), and 2 patients were diagnosed as no anterior cruciate injury under arthroscopy. When the Blumensaat angle was=15°, the probability of anterior cruciate ligament injury was greater. When the Blumensaat angle was 0° to 15°, the anterior cruciate ligament was more likely to be not injured. The Blumensaat angle=15° were used to diagnose the injury of anterior cruciate ligament. Compared with the results of arthroscopy, the coincidence rate of the total sample was 92.8%. Blumensaat angle is helpful to diagnose the ACL injuries. When the Blumensaat angle was =15°, the probability of ACL injury is greater.

  5. Preferred viewing distance and screen angle of electronic paper displays.

    Science.gov (United States)

    Shieh, Kong-King; Lee, Der-Song

    2007-09-01

    This study explored the viewing distance and screen angle for electronic paper (E-Paper) displays under various light sources, ambient illuminations, and character sizes. Data analysis showed that the mean viewing distance and screen angle were 495 mm and 123.7 degrees. The mean viewing distances for Kolin Chlorestic Liquid Crystal display was 500 mm, significantly longer than Sony electronic ink display, 491 mm. Screen angle for Kolin was 127.4 degrees, significantly greater than that of Sony, 120.0 degrees. Various light sources revealed no significant effect on viewing distances; nevertheless, they showed significant effect on screen angles. The screen angle for sunlight lamp (D65) was similar to that of fluorescent lamp (TL84), but greater than that of tungsten lamp (F). Ambient illumination and E-paper type had significant effects on viewing distance and screen angle. The higher the ambient illumination was, the longer the viewing distance and the lesser the screen angle. Character size had significant effect on viewing distances: the larger the character size, the longer the viewing distance. The results of this study indicated that the viewing distance for E-Paper was similar to that of visual display terminal (VDT) at around 500 mm, but greater than normal paper at about 360 mm. The mean screen angle was around 123.7 degrees, which in terms of viewing angle is 29.5 degrees below horizontal eye level. This result is similar to the general suggested viewing angle between 20 degrees and 50 degrees below the horizontal line of sight.

  6. Within tree variation of lignin, extractives, and microfibril angle coupled with the theoretical and near infrared modeling of microfibril angle

    Science.gov (United States)

    Brian K. Via; chi L. So; Leslie H. Groom; Todd F. Shupe; michael Stine; Jan. Wikaira

    2007-01-01

    A theoretical model was built predicting the relationship between microfibril angle and lignin content at the Angstrom (A) level. Both theoretical and statistical examination of experimental data supports a square root transformation of lignin to predict microfibril angle. The experimental material used came from 10 longleaf pine (Pinus palustris)...

  7. Can orbital angle morphology distinguish dogs from wolves?

    Science.gov (United States)

    Janssens, Luc; Spanoghe, Inge; Miller, Rebecca; Van Dongen, Stefan

    For more than a century, the orbital angle has been studied by many authors to distinguish dog skulls from their progenitor, the wolf. In early studies, the angle was reported to be different between dogs (49°-55°) and wolves (39°-46°). This clear difference was, however, questioned in a more recent Scandinavian study that shows some overlap. It is clear that in all studies several methodological issues were unexplored or unclear and that group sizes and the variety of breeds and wolf subspecies were small. Archaeological dog skulls had also not been studied. Our goal was to test larger and more varied groups and add archaeological samples as they are an evolutionary stage between wolves and modern dogs. We also tested the influence of measuring methods, intra- and inter-reliability, angle symmetry, the influence of variations in skull position and the possibility of measuring and comparing this angle on 3D CT scan images. Our results indicate that there is about 50 % overlap between the angle range in wolves and modern dogs. However, skulls with a very narrow orbital angle were only found in wolves and those with a very wide angle only in dogs. Archaeological dogs have a mean angle very close to the one of the wolves. Symmetry is highest in wolves and lowest in archaeological dogs. The measuring method is very reliable, for both inter- and intra-reliability (0.99-0.97), and most skull position changes have no statistical influence on the angle measured. Three-dimensional CT scan images can be used to measure OA, but the angles differ from direct measuring and cannot be used for comparison. Evolutionary changes in dog skulls responsible for the wider OA compared to wolf skulls are mainly the lateralisation of the zygomatic process of the frontal bone. Our conclusion is that the orbital angle can be used as an additional morphological measuring method to discern wolves from recent and archaeological dogs. Angles above 60° are certainly from recent dogs. Angles

  8. Apparent and microscopic dynamic contact angles in confined flows

    Science.gov (United States)

    Omori, Takeshi; Kajishima, Takeo

    2017-11-01

    An abundance of empirical correlations between a dynamic contact angle and a capillary number representing a translational velocity of a contact line have been provided for the last decades. The experimentally obtained dynamic contact angles are inevitably apparent contact angles but often undistinguished from microscopic contact angles formed right on the wall. As Bonn et al. ["Wetting and spreading," Rev. Mod. Phys. 81, 739-805 (2009)] pointed out, however, most of the experimental studies simply report values of angles recorded at some length scale which is quantitatively unknown. It is therefore hard to evaluate or judge the physical validity and the generality of the empirical correlations. The present study is an attempt to clear this clutter regarding the dynamic contact angle by measuring both the apparent and the microscopic dynamic contact angles from the identical data sets in a well-controlled manner, by means of numerical simulation. The numerical method was constructed so that it reproduced the fine details of the flow with a moving contact line predicted by molecular dynamics simulations [T. Qian, X. Wang, and P. Sheng, "Molecular hydrodynamics of the moving contact line in two-phase immiscible flows," Commun. Comput. Phys. 1, 1-52 (2006)]. We show that the microscopic contact angle as a function of the capillary number has the same form as Blake's molecular-kinetic model [T. Blake and J. Haynes, "Kinetics of liquid/liquid displacement," J. Colloid Interface Sci. 30, 421-423 (1969)], regardless of the way the flow is driven, the channel width, the mechanical properties of the receding fluid, and the value of the equilibrium contact angle under the conditions where the Reynolds and capillary numbers are small. We have also found that the apparent contact angle obtained by the arc-fitting of the interface behaves surprisingly universally as claimed in experimental studies in the literature [e.g., X. Li et al., "An experimental study on dynamic pore

  9. 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.

  10. The Influence of Face Angle and Club Path on the Resultant Launch Angle of a Golf Ball

    Directory of Open Access Journals (Sweden)

    Paul Wood

    2018-02-01

    Full Text Available A two-part experimental study was conducted in order to better understand how the delivered face angle and club path of a golf club influences the initial launch direction of a golf ball for various club types. A robust understanding of how these parameters influence the ball direction has implications for both coaches and club designers. The first study used a large sample of golfers hitting shots with different clubs. Initial ball direction was measured with a Foresight Sports camera system, while club delivery parameters were recorded with a Vicon motion capture system. The second study used a golf robot and Vision Research camera to measure club and ball parameters. Results from these experiments show that the launch direction fell closer to face angle than club path. The percent toward the face angle ranged from 61% to 83%, where 100% designates a launch angle entirely toward the face angle.

  11. The ideal male jaw angle--An Internet survey.

    Science.gov (United States)

    Mommaerts, Maurice Y

    2016-04-01

    The ideal male jaw angle has not been established. With the advent of additive manufacturing, precise customized shaping is a reality. This study aimed to define the ideal masculine mandibular angle as an aid for 3-dimensional (3D) design. An Internet survey was conducted using black/white photographs of celebrities and non-celebrities. Preferences regarding gonial angle (profile and frontal views), intergonial width and vertical jaw angle position (face frontal view), and angle curvature and definition in oblique views were obtained using simplified, unbalanced Likert scales. Constructs were defined for planning 3D implant designs. The preferred jaw angle had these characteristics: 130° in face profile view, intergonial width similar to facial width, vertical position in frontal view at the oral commissure or at least not below the lower lip, jawline slope in the face frontal view nearly parallel to (with a maximum 15° downward deviation from) a line extending from the lateral canthus to the alare, ascending ramus slope 65°-75° to the Frankfort horizontal, and curvature in the oblique view visible from earlobe to chin and not pointy. Photogrammetric analysis of panel preferences lead to constructs with values useful for the design of 3D printed jaw angles. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  12. Effect of Angle of Attack on Slope Climbing Performance

    Science.gov (United States)

    Creager, Colin M.; Jones, Lucas; Smith, Lauren M.

    2017-01-01

    Ascending steep slopes is often a very difficult challenge for off-road vehicles, whether on Earth or on extraterrestrial bodies. This challenge is even greater if the surface consists of loose granular soil that does not provide much shear strength. This study investigated how the path at which a vehicle traverses a slope, specifically the angle that it is commanded to drive relative to the base of the hill (the angle of attack), can affect its performance. A vehicle was driven in loose sand at slope angles up to 15 degrees and angles of attack ranging from 10 to 90 degrees. A novel photogrammetry technique was implemented to both track vehicle motion and create a three-dimensional profile of the terrain. This allowed for true wheel sinkage measurements. The study showed that though low angles of attack result in lower wheel slip and sinkage, the efficiency of the vehicles uphill motion increased at higher angles of attack. For slopes up to 15 degrees, a 90 degree angle of attack provided the greatest likelihood of successful ascent.

  13. Dynamic angle selection in X-ray computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Dabravolski, Andrei, E-mail: andrei.dabravolski@uantwerpen.be [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Batenburg, Kees Joost, E-mail: joost.batenburg@uantwerpen.be [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Centrum Wiskunde and Informatica (CWI), Science Park 123, 1098 XG Amsterdam (Netherlands); Sijbers, Jan, E-mail: jan.sijbers@uantwerpen.be [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium)

    2014-04-01

    Highlights: • We propose the dynamic angle selection algorithm for CT scanning. • The approach is based on the concept of information gain over a set of solutions. • Projection angles are selected based on the already available projection data. • The approach can lead to more accurate results from fewer projections. - Abstract: In X-ray tomography, a number of radiographs (projections) are recorded from which a tomogram is then reconstructed. Conventionally, these projections are acquired equiangularly, resulting in an unbiased sampling of the Radon space. However, especially in case when only a limited number of projections can be acquired, the selection of the angles has a large impact on the quality of the reconstructed image. In this paper, a dynamic algorithm is proposed, in which new projection angles are selected by maximizing the information gain about the object, given the set of possible new angles. Experiments show that this approach can select projection angles for which the accuracy of the reconstructed image is significantly higher compared to the standard angle selections schemes.

  14. 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.

  15. Patient-specific rhytidectomy: finding the angle of maximal rejuvenation.

    Science.gov (United States)

    Jacono, Andrew A; Ransom, Evan R

    2012-09-01

    Rhytidectomy is fundamentally an operation of tissue release and resuspension, although the manner and direction of suspension are subject to perpetual debate. The authors describe a method for identifying the angle of maximal rejuvenation during rhytidectomy and quantify the resulting angle and its relationship to patient age. Patients were prospectively enrolled; demographic data, history, and operative details were recorded. Rhytidectomies were performed by the senior author (AAJ). After complete elevation, the face-lift flap was rotated in a medially-based arc (0-90°) while attention was given to the submental area, jawline, and midface. The angle of maximal rejuvenation for each hemiface was identified as described, and the flap was resuspended. During redraping, measurements of vertical and horizontal skin excess were recorded in situ. The resulting angle of lift was then calculated for each hemiface using trigonometry. Symmetry between sides was determined, and the effect of patient age on this angle was assessed. Three hundred hemifaces were operated (147 women; 3 men). Mean age was 60 years (range, 37-80 years). Mean resulting angle for the cohort was 60° from horizontal (range, 46-77°). This was inversely correlated with patient age (r = -.3). Younger patients (<50 years, 64°) had a significantly more vertical angle than older patients (≥70 years, 56°; P < .0002). No significant intersubject difference was found between hemifaces (P = .53). The authors present a method for identifying the angle of maximal rejuvenation during rhytidectomy. This angle was more superior than posterior in all cases and is intimately related to patient age. Lasting results demand a detailed anatomical understanding and strict attention to the direction and degree of laxity.

  16. Hybrid Projectile Body Angle Estimation for Selectable Range Increase

    Science.gov (United States)

    Gioia, Christopher J.

    A Hybrid Projectile (HP) is a tube launched munition that transforms into a gliding UAV, and is currently being researched at West Virginia University. A simple launch timer was first envisioned to control the transformation point in order to achieve maximum distance. However, this timer would need to be reprogrammed for any distance less than maximum range due to the nominal time to deployment varying with launch angle. A method was sought for automatic wing deployment that would not require reprogramming the round. A body angle estimation system was used to estimate the pitch of the HP relative to the Earth to determine when the HP is properly oriented for the designed glide slope angle. It was also necessary to filter out noise from a simulated inertial measurement unit (IMU), GPS receiver, and magnetometer. An Extended Kalman Filter (EKF) was chosen to estimate the Euler angles, position and velocity of the HP while an algorithm determined when to deploy the wings. A parametric study was done to verify the optimum deployment condition using a Simulink aerodynamic model. Because range is directly related to launch angle, various launch angles were simulated in the model. By fixing the glide slope angle to -10° as a deployment condition for all launch angles, the range differed only by a maximum of 6.1% from the maximum possible range. Based on these findings, the body angle deployment condition provides the most flexible option to maintain maximum distance without the need of reprogramming. Position and velocity estimates were also determined from the EKF using the GPS measurements. Simulations showed that the EKF estimates exhibited low root mean squared error values, corresponding to less than 3% of the total position values. Because the HP was in flight for less than a minute in this experiment, the drift encountered was acceptable.

  17. Modified dark room provocative test for primary angle closure.

    Science.gov (United States)

    Li, Dejiao; Wang, Ningli; Wang, Bingsong; Wang, Tao; Jonas, Jost B

    2012-03-01

    To examine the diagnostic value of a modified dark room provocative test (DRPT) in detecting primary closure of the anterior chamber angle. The cross-sectional observational prospective clinical study included suspects of primary angle closure. Using anterior segment optical coherence tomography (AS-OCT), we measured the anterior chamber angle configuration at room light and after 3 minutes of dark adaptation. Gonioscopy and Perkin's applanation tonometry were performed in room light conditions at baseline and after 1.5 hours of dark adaptation. The number of closed angle quadrants assessed on AS-OCT images and upon gonioscopy were recorded. The DRPT was positive, if intraocular pressure increased by ≥8 mm Hg after 1.5 hours of dark adaptation. The study included 76 subjects (76 eyes). Among 32 (42%) eyes with a positive DRPT, the number of eyes with an increased number of closed angle quadrants was significantly higher for the OCT examination at 3 minutes of dark adaptation than for gonioscopy at 1.5 hours of dark adaptation [29 (91%) eyes vs 21 (66%) eyes; P=0.01]. Kappa statistics showed a moderate agreement between increased closed angle quadrants obtained both after 3 minutes of dark adaptation (κ=0.44; Pdark room test (κ=0.45; Pdark room test. A modified DRPT with an anterior chamber angle assessment by OCT at 3 minutes of dark adaptation as compared with a gonioscopic angle assessment after 1.5 hours of dark adaptation had a higher diagnostic precision in predicting primary angle closure.

  18. [Laser Iridotomy - In Cases of Acute Angle Closure Only?

    Science.gov (United States)

    Handzel, Daniel M; Meyer, Carsten H; Wegener, Alfred

    2017-11-01

    The narrowing of the chamber angle-as a result of anatomic predispositions like high hyperopia or increasing lens thickness-poses the greatest risk for acute angle closure. A laser iridotomy counts as a standard procedure in cases of acute angle closure, whereas there are no coherent recommendations or guidelines for a prophylactic therapy. Modern imaging techniques, such as anterior segment optical coherence tomography or Scheimpflug photography, can give valuable information for the planning of treatment. This review presents traditional and modern imaging techniques and summarises recommendations for action in relation to recent publications. Georg Thieme Verlag KG Stuttgart · New York.

  19. Influence of Stockpile Angle in Natural Drying of Laterite Ore

    Directory of Open Access Journals (Sweden)

    Yoalbys Retirado-Mediaceja

    2016-10-01

    Full Text Available Natural drying is performed at Cuban nickel plants by depositing bulk ore in the open. The ore is currently being stockpiled without much consideration for the impact of the drying surface angle on the process power behavior. Simulations were carried out in this investigation, which prove that an increased triangular stockpile angle considerably reduces natural drying efficiency. A 45 sexagesimal degree angle to the horizontal plane results in exposure of a large volume of ore to natural drying and guarantees adequate energy performance.

  20. Low-cost large-angle steering mirror development

    Science.gov (United States)

    Wassom, Steven R.

    2009-08-01

    The Space Dynamics Laboratory has combined internal funds with its background in space-rated mechanisms to develop a prototype low-cost large-angle 2-axis fine steering mirror (FSM). The FSM has a 75-mm clear aperture, 30-degree mechanical elevation angle, 120-degree mechanical azimuth angle, and a 70-Hertz small-amplitude bandwidth. Key components include a rotary voice coil, unique patent-pending feedback sensor, brushless DC motor and optical encoder. Average error is portable demonstration electronics development, and thermal-vacuum testing to pressures down to 1e-7 torr and temperatures down to 164 K.

  1. Control of Angular Intervals for Angle-Multiplexed Holographic Memory

    Science.gov (United States)

    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.

  2. Large angle tracking and high discriminating tracking in nuclear emulsion

    International Nuclear Information System (INIS)

    Matsuo, Tomokazu; Shibuya, Hiroshi; Ogawa, Satoru; Fukuda, Tsutomu; Mikado, Shoji

    2015-01-01

    Nuclear emulsion is a high resolution and re-analyzable detector. Conventional “Track Selector” which have angle acceptance |tan θ|<0.6 are widely used to find tracks in emulsion. We made a new track selector “Fine Track Selector” (FTS) which has large angle acceptance and high discriminating ability. The FTS reduces fake tracks using new algorithms, navigation etc. FTS also keeps finding efficiency of tracks around 90% in an angle range of |tan θ| < 3.5. FTS was applied to the τ candidate in OPERA and no additional tracks found. FTS will be useful to our new J-PARC emulsion experiment.

  3. Indoor Measurement of Angle Resolved Light Absorption by Black Silicon

    DEFF Research Database (Denmark)

    Amdemeskel, Mekbib Wubishet; Iandolo, Beniamino; Davidsen, Rasmus Schmidt

    2017-01-01

    Angle resolved optical spectroscopy of photovoltaic (PV) samples gives crucial information on PV panels under realistic working conditions. Here, we introduce measurements of angle resolved light absorption by PV cells, performed indoors using a collimated high radiance broadband light source. Our...... indoor method offers a significant simplification as compared to measurements by solar trackers. As a proof-of-concept demonstration, we show characterization of black silicon solar cells. The experimental results showed stable and reliable optical responses that makes our setup suitable for indoor......, angle resolved characterization of solar cells....

  4. The modified Cassie’s equation and contact angle hysteresis

    KAUST Repository

    Xu, Xianmin

    2012-08-29

    In this paper, we derive a modified Cassie\\'s equation for wetting on chemically patterned surfaces from a homogenization approach. The derivation reveals that effective contact angle is a local average of the static contact angle along the contact line which describes all possible equilibrium states including the local minimum of the free energy of the system. The usual Cassie\\'s state which corresponds to the global minimum is only a special case. We then discuss the contact angle hysteresis on chemically patterned surfaces. © 2012 Springer-Verlag.

  5. Optimal fringe angle selection for digital fringe projection technique.

    Science.gov (United States)

    Wang, Yajun; Zhang, Song

    2013-10-10

    Existing digital fringe projection (DFP) systems mainly use either horizontal or vertical fringe patterns for three-dimensional shape measurement. This paper reveals that these two fringe directions are usually not optimal where the phase change is the largest to a given depth variation. We propose a novel and efficient method to determine the optimal fringe angle by projecting a set of horizontal and vertical fringe patterns onto a step-height object and by further analyzing two resultant phase maps. Experiments demonstrate the existence of the optimal angle and the success of the proposed optimal angle determination method.

  6. Projection angles of mandibular condyles in panoramic and transcranial radiographs

    International Nuclear Information System (INIS)

    Nah, Kyung Soo

    2006-01-01

    To evaluate the true projection angles of film-side mandibular condyles in panoramic and transcranial radiographs. 52 panoramic and transcranial radiographs of 4 condyles from two human dry mandibles with gradual horizontal and vertical angle changes were taken. The results were compared with the standard panoramic and transcranial radiographs and the identical pairs were selected. Panoramic radiography projected 10 degree to the film-sided condyles both horizontally and vertically. Transcranial radiography projected 15 degree to the film-sided condyles vertically. The medical and lateral poles were not forming the outline of condylar images in both projections when the horizontal angles of condyles were not sufficiently big enough

  7. Investigation of ferromagnetic domain structures by neutron small angle scattering

    International Nuclear Information System (INIS)

    Schild, L.

    1984-01-01

    The magnetic small angle scattering of thermal neutrons caused by magnetic refraction at domain walls of ferromagnetic materials without texture has been investigated. Experiments on Fe-Si alloys with a twin crystal diffractometer were carried out. It is shown that the mean extension of magnetic basic units (domains as well as parallel wall systems) can be determined. A comparison of grain sizes determined metallographically with domain sizes obtained by neutron small-angle scattering has shown that neither mean grain size nor domain size can be assessed by small-angle scattering experiments

  8. Relationship between retinal lattice degeneration and open angle glaucoma.

    Science.gov (United States)

    Rahimi, Mansour

    2005-01-01

    Patients with retinal disorders may develop glaucoma of both a primary and secondary type. Pigment may contribute to trabecular obstruction in some patients with open-angle glaucoma. Lattice degeneration of the retina in its typical form is a sharply demarcated, circumferentially oriented, degenerative process with significant alterations of retinal pigmentation. The association between myopia, open angle glaucoma and pigment dispersion is striking. Therefore, it could be postulated that there is significant prevalence of open angle glaucoma in patients with retinal lattice degeneration, especially in combination with myopia.

  9. Research advances on multifocal electroretinogram in primary open angle glaucoma

    Directory of Open Access Journals (Sweden)

    Feng-Fei Mo

    2013-10-01

    Full Text Available Primary open angle glaucoma is a chronic and progressive optic neuropathy. It can lead to serious damage of visual impairment, and it is an important eye disease of blindness. Multifocal electroretinogram is a new way to measure visual electrophysiology. It can measure electroretinogram of the whole visual field of many small parts in a relatively short period of time, and it can reflect the function of regional retina. It has an extremely important value for early diagnosis of primary open angle glaucoma. The research advances on multifocal electroretinogram in diagnosing primary open angle glaucoma were summarized in this paper.

  10. ILC Extraction Line for 14 mrad Crossing Angle

    International Nuclear Information System (INIS)

    Nosochkov, Y.; Markiewicz, T.; Maruyama, T.; Seryi, A.; Parker, B.

    2005-01-01

    The earlier studies of the ILC extraction line for 20 mrad and 2 mrad crossing angle options [1]-[5] showed that the 20 mrad design has an advantage of a simpler beamline and lower extraction beam loss because of the independent incoming and extraction optics. However, the large 20 mrad crossing angle requires the use of a crab cavity correction, increases synchrotron radiation emittance growth in the solenoid, and increases photon backscattering from the forward calorimeter of the detector. To reduce these effects, an attempt has been made to minimize the crossing angle while keeping the extraction and incoming lines separate. A new quadrupole scheme near the interaction point has been proposed which allows a reduction of the crossing angle to 14 mrad [6]. The optics design and results of tracking and background simulations for the 14 mrad extraction line are presented

  11. Multi Angle Imaging With Spectral Remote Sensing for Scene Classification

    National Research Council Canada - National Science Library

    Prasert, Sunyaruk

    2005-01-01

    .... QuickBird panchromatic (0.61 meter) and multispectral (2.44 meter) imagery collected in July 2003 are examined to determine the impact of adding multi-angles and filtered texture information to the standard MSI classification approaches...

  12. Shear wave splitting in the Isparta Angle, southwestern Turkey ...

    Indian Academy of Sciences (India)

    broadband station in the Isparta Angle,southwestern Turkey.We selected 21 good quality seismic events out of nearly 357 earthquakes and calculated splitting parameters (polarization direction of fast wave, and delay time between fast and ...

  13. Small-angle neutron scattering studies of sodium butyl benzene

    Indian Academy of Sciences (India)

    Na-NBBS), in aqueous solutions is investigated by small-angle neutron scattering (SANS). Nearly ellipsoidal aggregates of Na-NBBS at concentrations well above its minimum hydrotrope concentration were detected by SANS. The hydrotrope ...

  14. Setting of angles on machine tools speeded by magnetic protractor

    Science.gov (United States)

    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.

  15. Angle Stability Analysis for Voltage-Controlled Converters

    DEFF Research Database (Denmark)

    Lin, Hengwei; Jia, Chenxi; Guerrero, Josep M.

    2017-01-01

    a criterion to analyze the quasi-steady angle stability and the direct current (DC) side stability for VSCs. The operating limit and the angle instability mechanism are revealed, which is generally applicable to the voltage-controlled converters. During the analysis, the influence of the parameters on angle...... stability is studied. Further, the difference on instability mechanism between power electronic converters and synchronous generators are explained in detail. Finally, experiment results with corrective actions verify the analysis.......Power electronics based voltage source converters (VSCs) keep increasing in modern electrical systems. As a branch of stability problems, angle stability is significant for an electrical system. Based on small disturbance analysis and time scale decomposition perspective, this paper proposes...

  16. Small-angle neutron scattering studies of sodium butyl benzene ...

    Indian Academy of Sciences (India)

    Na-NBBS), in aqueous solutions is investigated by small-angle neutron scattering (SANS). Nearly ellipsoidal aggregates of Na-NBBS at concentrations well above its minimum hydrotrope concentration were detected by SANS. The hydrotrope ...

  17. Multi-angle Imaging SpectroRadiometer (MISR)

    Data.gov (United States)

    National Aeronautics and Space Administration — The Multi-angle Imaging SpectroRadiometer (MISR) was successfully launched into sun-synchronous polar orbit aboard Terra, NASA's first Earth Observing System (EOS)...

  18. Ultra small angle neutron scattering from superconducting filament structures

    International Nuclear Information System (INIS)

    Amenitsch, H.

    1999-01-01

    With a perfect crystal camera, ultra small-angle scattering measurements were performed to investigate the internal diffusion process of tin inside a superconducting multi-filament wire caused by a temperature treatment. Commercially available Nb 3 Sn superconducting multi-filament wires were treated at 700 C with varying ageing times up to 144 h. A theoretical model taking into account the geometrical form, the size distribution, the interference term and the multiple scattering has been developed to understand and to describe the small angle diffraction pattern. Additionally, the diffusion of H and D into the filament wires was used to vary the scattering length density inside the wires. The results show a direct relationship between the different technological treatments and the characteristic small-angle scattering parameters, like Guinier radius and small-angle scattering probability. (orig.) [de

  19. Quantized contact angles in the dewetting of a structured liquid.

    Science.gov (United States)

    Ilton, Mark; Stasiak, Pawel; Matsen, Mark W; Dalnoki-Veress, Kari

    2014-02-14

    We investigate the dewetting of a disordered melt of diblock copolymer from an ordered residual wetting layer. In contrast to simple liquids where the wetting layer has a fixed thickness and the droplets exhibit a single unique contact angle with the substrate, we find that structured liquids of diblock copolymer exhibit a discrete series of wetting layer thicknesses each producing a different contact angle. These quantized contact angles arise because the substrate and air surfaces each induce a gradient of lamellar order in the wetting layer. The interaction between the two surface profiles creates an effective interface potential that oscillates with film thickness, thus, producing a sequence of local minimums. The wetting layer thicknesses and corresponding contact angles are a direct measure of the positions and depths of these minimums. Self-consistent field theory is shown to provide qualitative agreement with the experiment.

  20. ILC extraction line for 14 mrad crossing angle

    International Nuclear Information System (INIS)

    Nosochkov, Y.; Markiewicz, T.; Maruyama, T.; Seryi, A.; Parker, B.

    2006-01-01

    The earlier studies of the ILC extraction line for 20 mrad and 2 mrad crossing angle options showed that the 20 mrad design has an advantage of a simpler beamline and lower extraction beam loss because of the independent incoming and extraction optics. However, the large 20 mrad crossing angle requires the use of a crab cavity correction, increases synchrotron radiation emittance growth in the solenoid, and increases photon backscattering from the forward calorimeter of the detector. To reduce these effects, an attempt has been made to minimize the crossing angle while keeping the extraction and incoming lines separate. A new quadrupole scheme near the interaction point has been proposed which allows a reduction of the crossing angle to 14 mrad. The optics design and results of tracking and background simulations for the 14 mrad extraction line are presented. (author)

  1. Parameterization of ion channeling half-angles and minimum yields

    Science.gov (United States)

    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

  2. Report of the evaluation by the Ad Hoc Review Committee on Materials Science Research. In-advance evaluation in fiscal year 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-11-01

    The Research Evaluation Committee, which consisted of 13 members from outside of the Japan Atomic Energy Research Institute (JAERI), set up an Ad Hoc Review Committee on Materials Science Research in accordance with the Fundamental Guideline for the Evaluation of Research and Development (R and D) at JAERI' and its subsidiary regulations in order to evaluate the adequacy of the R and D programs to be implemented for five years starting in Fiscal Year 2003 at Department of Materials Science in Tokai Research Establishment of JAERI. The Ad Hoc Review Committee consisted of eight specialists from outside of JAERI. The Ad Hoc Review Committee conducted its activities from April 2002 to August 2002. The evaluation was performed on the basis of the materials submitted in advance and of the oral presentations made at the Ad Hoc Review Committee meeting which was held on June 5th, 2002, in line with the items, viewpoints, and criteria for the evaluation specified by the Research Evaluation Committee. The result of the evaluation by the Ad Hoc Review Committee was submitted to the Research Evaluation Committee, and was judged to be appropriate at its meeting held on August 5th, 2002. This report describes the result of the evaluation by the Ad Hoc Review Committee on Materials Science Research. (author)

  3. Report of the evaluation by the Ad Hoc Review Committee on advance science research. Result evaluation, interim evaluation, in-advance evaluation in fiscal year 2003

    International Nuclear Information System (INIS)

    2003-11-01

    The Research Evaluation Committee, which consisted of 13 members from outside of the Japan Atomic Energy Research Institute (JAERI), set up an Ad Hoc Review Committee on Advanced Science Research in accordance with the Fundamental Guideline for the Evaluation of Research and Development (R and D) at JAERI' and its subsidiary regulations in order to evaluate the accomplishments of the research completed in Fiscal Year 2002, the accomplishments of the research started in Fiscal Year 2001, and the adequacy of the programs of the research to be started in Fiscal Year 2004 at Advanced Science Research Center of JAERI. The Ad Hoc Review Committee consisted of nine specialists from outside of JAERI. The Ad Hoc Review Committee conducted its activities from May to July 2003. The evaluation was performed on the basis of the materials submitted in advance and of the oral presentations made at the Ad Hoc Review Committee meeting which was held on June 24, 2003, in line with the items, viewpoints, and criteria for the evaluation specified by the Research Evaluation Committee. The result of the evaluation by the Ad Hoc Review Committee was submitted to the Research Evaluation Committee, and was judged to be appropriate at its meeting held on August 4, 2003. This report describes the result of the evaluation by the Ad Hoc Review Committee on Advanced Science Research. (author)

  4. Report of the evaluation by the Ad Hoc Review Committee on Advance Science Research. Result evaluation, interim evaluation, in-advance evaluation in fiscal year 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-11-01

    The Research Evaluation Committee, which consisted of 13 members from outside of the Japan Atomic Energy Research Institute (JAERI), set up an Ad Hoc Review Committee on Advanced Science Research in accordance with the Fundamental Guideline for the Evaluation of Research and Development (R and D) at JAERI' and its subsidiary regulations in order to evaluate the accomplishments of the research completed in Fiscal Year 2001, the accomplishments of the research started in Fiscal Year 2000, and the adequacy of the programs of the research to be started in Fiscal Year 2003 at Advanced Science Research Center of JAERI. The Ad Hoc Review Committee consisted of eight specialists from outside of JAERI. The Ad Hoc Review Committee conducted its activities from May to July 2002. The evaluation was performed on the basis of the materials submitted in advance and of the oral presentations made at the Ad Hoc Review Committee meeting which was held on June 4, 2002, in line with the items, viewpoints, and criteria for the evaluation specified by the Research Evaluation Committee. The result of the evaluation by the Ad Hoc Review Committee was submitted to the Research Evaluation Committee, and was judged to be appropriate at its meeting held on August 5, 2002. This report describes the result of the evaluation by the Ad Hoc Review Committee on Advanced Science Research. (author)

  5. Comparison of different passive knee extension torque-angle assessments

    International Nuclear Information System (INIS)

    Freitas, Sandro R; Vaz, João R; Bruno, Paula M; Valamatos, Maria J; Mil-Homens, Pedro

    2013-01-01

    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)

  6. A study of arrival angles of natural VLF waves

    Science.gov (United States)

    Apsen, A. G.; Fedorenko, Iu. V.; Chernysheva, S. P.; Kleimenova, N. G.; Putilin, A. N.

    Methods are proposed for determining the arrival angles of natural VLF waves at a ground-based observatory. A device in which the proposed method is implemented is described, and questions regarding its calibration and suppression of lightning-induced and industrial noise are addressed. Measurements of natural VLF-wave arrival angles, carried out in the auroral zone in the Murmansk region are presented.

  7. Anthropometric study of angle of femoral torsion in Maharashtrian population

    Directory of Open Access Journals (Sweden)

    Anil Kumar Dwivedi

    2016-01-01

    Full Text Available Introduction: Angle of femoral torsion is a normal torsion or twist present in femur that plays an important role in stability and function of the hip joint. The angle of femoral torsion can be defined as the angle formed by femoral condyle′s plane (bicondylar plane and a plane passing through center of neck and femoral head. Abnormal angle of femoral torsion has been implicated in the etiology of hip osteoarthrosis and developmental dysplasia of hip joint. Materials and Methods: This study was carried out on unpaired 280, adult human femora devoid of any gross pathology, 139 male (65 right and 74 left, and 141 female (71 right and 70 left from bone banks of three medical colleges of Maharashtra. The gender of each specimen was determined by the established practice. Femora were evaluated by Kingsley Olmsted method, and data were tabulated and statistically analyzed. Results: The average angle of femoral torsion 13.39° and 11.23° on the right and left side respectively in male, 16.21° and 13.23° on the right and left side, respectively, in female. Statistical analysis using Student′s "t"-test revealed significant difference (P < 0.05, greater angle of femoral torsion in female and on the right side. Conclusion: Knowledge of angle of femoral torsion is becoming significant nowadays with an increase in demand for total hip replacement, as the angle of femoral torsion is crucial to attain a normal activity of the replaced joint.

  8. Virtual characterization of delamination failures in pultruded GFRP angles

    OpenAIRE

    Girão Coelho, Ana M.; Mottram, J. Toby; Matharu, Navroop S.

    2016-01-01

    This paper deals with the application of cohesive zone models to study delamination failures in leg-angles of pultruded glass fibre reinforced polymer material using the general-purpose finite element software Abaqus. The objective of the study is present a finite element modelling methodology that can, for example, help to fill-in knowledge gaps in the available experimental data pertaining to the tying force resistance of angle-cleated jointing in frame construction. It may be used to optim...

  9. Light Airplane Crash Test at Three Pitch Angles

    Science.gov (United States)

    Vaughan, Victor L., Jr.; Alfaro-Bou, Emilio

    1979-01-01

    Three similar twin-engine general-aviation airplane specimens were crash tested at the Langley Impact Dynamics Research Facility at 27 m/sec, a flight-path angle of -15deg, and pithch angles of -15deg, 0deg, and 15deg. Other crash parameters were held constant. The test facility, instrumentation, test specimens, and test method are briefly described. Structural damage and accelerometer data for each of the three impact conditions are presented and discussed.

  10. Light airplane crash tests at three pitch angles

    Science.gov (United States)

    Vaughan, V. L., Jr.; Alfaro-Bou, E.

    1979-01-01

    Three similar twin-engine general aviation airplane specimens were crash tested at an impact dynamics research facility at 27 m/sec, a flight path angle of -15 deg, and pitch angles of -15 deg, 0 deg, and 15 deg. Other crash parameters were held constant. The test facility, instrumentation, test specimens, and test method are briefly described. Structural damage and accelerometer data for each of the three impact conditions are presented and discussed.

  11. Exchange interpretation of anomalous back angle heavy ion elastic scattering

    International Nuclear Information System (INIS)

    Zisman, M.S.

    1977-10-01

    Anomalous back angle oscillations in the angular distributions obtained in the elastic scattering of 16 O + 28 Si and 12 C + 28 Si have been interpreted in terms of an elastic cluster transfer comparable to that observed in other heavy ion reactions. The calculations appear to at least qualitatively explain the data with respect to the existence and phase of the back angle oscillations. The results indicate that an exchange mechanism may play an important role in the oscillations

  12. BIPHASIC TREATMENT OF 2ND CLASS ANGLE ANOMALIES

    OpenAIRE

    C. Romanec; R. Stanciu; Anca Telmecea; Valentina Dorobat

    2011-01-01

    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 cli...

  13. Acquisition of Infrared Variable Angle Spectroscopic Ellipsometer (IR-VASE)

    Science.gov (United States)

    2016-04-22

    SECURITY CLASSIFICATION OF: This award was used to acquire a J.A. Woollam Infrared Variable Angle Spectroscopic Ellipsometer ( IR -VASE). The IR -VASE...unit is capable of obtaining crucial IR information of ultrathin films whilst being complemented with ellipsometry data. This powerful and versatile...Unlimited UU UU UU UU 22-04-2016 1-Feb-2015 31-Jan-2016 Final Report: Acquisition of Infrared Variable Angle Spectroscopic Ellipsometer ( IR -VASE) The

  14. Photovoltaic Modules: Effect of Tilt Angle on Soiling

    Science.gov (United States)

    Cano, Jose

    2011-12-01

    Photovoltaic (PV) systems are one of the next generation's renewable energy sources for our world energy demand. PV modules are highly reliable. However, in polluted environments, over time, they will collect grime and dust. There are also limited field data studies about soiling losses on PV modules. The study showed how important it is to investigate the effect of tilt angle on soiling. The study includes two sets of mini-modules. Each set has 9 PV modules tilted at 0, 5, 10, 15, 20, 23, 30, 33 and 40°. The first set called "Cleaned" was cleaned every other day. The second set called "Soiled" was never cleaned after the first day. The short circuit current, a measure of irradiance, and module temperature was monitored and recorded every two minutes over three months (January-March 2011). The data were analyzed to investigate the effect of tilt angle on daily and monthly soiling, and hence transmitted solar insolation and energy production by PV modules. The study shows that during the period of January through March 2011 there was an average loss due to soiling of approximately 2.02% for 0° tilt angle. Modules at tilt angles 23° and 33° also have some insolation losses but do not come close to the module at 0° tilt angle. Tilt angle 23° has approximately 1.05% monthly insolation loss, and 33° tilt angle has an insolation loss of approximately 0.96%. The soiling effect is present at any tilt angle, but the magnitude is evident: the flatter the solar module is placed the more energy it will lose.

  15. Measurement of the angle of superficial tension by images

    Science.gov (United States)

    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.

  16. Determination of angle of inclination for optimum power production ...

    African Journals Online (AJOL)

    This study evaluates the performance of the photovoltaic modules at different tilt angle (angle of inclination) from 5º to 90º. The solar panel of 45 Watts capacity was placed on the manual tracker between the hours of 7:00am and 6:15pm on the geographical location of latitude of 40 55' 58” North and longitude of 60 59' 55” ...

  17. NORMAL AXIAL ANGLES OF THE KNEE JOINT IN ADULT ...

    African Journals Online (AJOL)

    hi-tech

    2003-08-01

    Aug 1, 2003 ... centres of the hip, knee and ankle all lie on a straight line, forming the mechanical axis of the lower limb (Figure 1). This axis coincides with the anatomical axis of the tibia in the leg, while in the thigh it forms an angle of 6° with the anatomical axis of the femoral shaft in Caucasians (1). The mechanical angle ...

  18. Detection of Contact Binaries Using Sparse High Phase Angle Lightcurves

    OpenAIRE

    Lacerda, Pedro

    2007-01-01

    We show that candidate contact binary asteroids can be efficiently identified from sparsely sampled photometry taken at phase angles >60deg. At high phase angle, close/contact binary systems produce distinctive lightcurves that spend most of the time at maximum or minimum (typically >1mag apart) brightness with relatively fast transitions between the two. This means that a few (~5) sparse observations will suffice to measure the large range of variation and identify candidate contact binary s...

  19. Contact angle control of sessile drops on a tensioned web

    Science.gov (United States)

    Park, Janghoon; Kim, Dongguk; Lee, Changwoo

    2018-04-01

    In this study, the influence of the change of tension applied to flexible and thin web substrate on the contact angle of sessile drop in roll-to-roll system was investigated. Graphene oxide and deionized water solutions were used in the experiments. Tension was changed to 29, 49, and 69 N, and the casting distance of the micropipette and the material was set to 10, 20, and 40 mm, and the droplet volume was set to 10, 20, and 30 μL, respectively. Statistical analysis of three variables and analysis of the variance methodology showed that the casting distance was most significant for the contact angle change, and the most interesting tension variable was also affected. The change in tension caused the maximum contact angle to change by 5.5°. The tension was not uniform in the width direction. When the droplet was applied in the same direction in the width direction, it was confirmed that the tension unevenness had great influence on the contact angle up to 11°. Finally, the casting distance, which has a large effect on the contact angle, was calibrated in the width direction to reduce the width direction contact angle deviation to 1%. This study can be applied to fine patterning research using continuous inkjet printing and aerosol jet printing, which are roll-to-roll processes based on droplet handling.

  20. A Universal Formula for Extracting the Euler Angles

    Science.gov (United States)

    Shuster, Malcolm D.; Markley, F. Landis

    2004-01-01

    Recently, the authors completed a study of the Davenport angles, which are a generalization of the Euler angles for which the initial and final Euler axes need not be either mutually parallel or mutually perpendicular or even along the coordinate axes. During the conduct of that study, those authors discovered a relationship which can be used to compute straightforwardly the Euler angles characterizing a proper-orthogonal direction-cosine matrix for an arbitrary Euler-axis set satisfying n(sub 1) x n(sub 2) = 0 and n(sub 3) x n(sub 1) = 0, which is also satisfied by the more usual Euler angles we encounter commonly in the practice of Astronautics. Rather than leave that relationship hidden in an article with very different focus from the present Engineering note, we present it and the universal algorithm derived from it for extracting the Euler angles from the direction-cosine matrix here. We also offer literal "code" for performing the operations, numerical examples, and general considerations about the extraction of Euler angles which are not universally known, particularly, the treatment of statistical error.

  1. Hydrologic controls on junction angle of river networks

    Science.gov (United States)

    Hooshyar, Milad; Singh, Arvind; Wang, Dingbao

    2017-05-01

    The formation and growth of river channels and their network evolution are governed by the erosional and depositional processes operating on the landscape due to the movement of water. The branching angles, i.e., the angle between two adjoining channels, in drainage networks are important features related to the network topology and contain valuable information about the forming mechanisms of the landscape. Based on the channel networks extracted from 1 m Digital Elevation Models of 120 catchments with minimal human impacts across the United States, we show that the junction angles have two distinct modes with α1¯≈49.5° and α2¯≈75.0°. The observed angles are physically explained as the optimal angles that result in minimum energy dissipation and are linked to the exponent characterizing the slope-area curve. Our findings suggest that the flow regimes, debris-flow dominated or fluvial, have distinct characteristic angles which are functions of the scaling exponent of the slope-area curve. These findings enable us to understand the geomorphic signature of hydrologic processes on drainage networks and develop more refined landscape evolution models.

  2. Limbus Impact on Off-angle Iris Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Santos-Villalobos, Hector J [ORNL; Thompson, Joseph W [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL

    2013-01-01

    The accuracy of iris recognition depends on the quality of data capture and is negatively affected by several factors such as angle, occlusion, and dilation. Off-angle iris recognition is a new research focus in biometrics that tries to address several issues including corneal refraction, complex 3D iris texture, and blur. In this paper, we present an additional significant challenge that degrades the performance of the off-angle iris recognition systems, called the limbus effect . The limbus is the region at the border of the cornea where the cornea joins the sclera. The limbus is a semitransparent tissue that occludes a side portion of the iris plane. The amount of occluded iris texture on the side nearest the camera increases as the image acquisition angle increases. Without considering the role of the limbus effect, it is difficult to design an accurate off-angle iris recognition system. To the best of our knowledge, this is the first work that investigates the limbus effect in detail from a biometrics perspective. Based on results from real images and simulated experiments with real iris texture, the limbus effect increases the hamming distance score between frontal and off-angle iris images ranging from 0.05 to 0.2 depending upon the limbus height.

  3. Hybrid algorithm for rotor angle security assessment in power systems

    Directory of Open Access Journals (Sweden)

    D. Prasad Wadduwage

    2015-08-01

    Full Text Available Transient rotor angle stability assessment and oscillatory rotor angle stability assessment subsequent to a contingency are integral components of dynamic security assessment (DSA in power systems. This study proposes a hybrid algorithm to determine whether the post-fault power system is secure due to both transient rotor angle stability and oscillatory rotor angle stability subsequent to a set of known contingencies. The hybrid algorithm first uses a new security measure developed based on the concept of Lyapunov exponents (LEs to determine the transient security of the post-fault power system. Later, the transient secure power swing curves are analysed using an improved Prony algorithm which extracts the dominant oscillatory modes and estimates their damping ratios. The damping ratio is a security measure about the oscillatory security of the post-fault power system subsequent to the contingency. The suitability of the proposed hybrid algorithm for DSA in power systems is illustrated using different contingencies of a 16-generator 68-bus test system and a 50-generator 470-bus test system. The accuracy of the stability conclusions and the acceptable computational burden indicate that the proposed hybrid algorithm is suitable for real-time security assessment with respect to both transient rotor angle stability and oscillatory rotor angle stability under multiple contingencies of the power system.

  4. Evaluation of the anterior chamber angle in pseudoexfoliation syndrome.

    Science.gov (United States)

    Iwanejko, Małgorzata; Turno-Kręcicka, Anna; Tomczyk-Socha, Martyna; Kaczorowski, Kamil; Grzybowski, Andrzej; Misiuk-Hojło, Marta

    2017-08-01

    Pseudoexfoliation syndrome (PEX) is the most frequently identifiable cause of secondary open-angle glaucoma, known as pseudoexfoliation glaucoma. The exact pathophysiology and etiology of PEX and associated glaucoma remains obscure. The purpose of this study was to determine the differences in the morphology of the anterior chamber angle in people with pseudoexfoliation syndrome and pseudoexfoliation glaucoma compared to a control group. We also evaluated the correlation between intraocular pressure (IOP) and pigmentation of the angle with the amount of exfoliated material in the anterior segment. The study group was composed of 155 eyes from 103 patients aged between 43 and 86 years. Each patient underwent a complete ophthalmological examination. Some difference was found in intraocular pressure between the PEX group and the control group and between the pseudoexfoliation glaucoma group and the control group, but no significant difference was found between the 2 study groups. There was a significant difference in the incidence of some degree of pigmentation in the anterior chamber angle and no difference in the widths of the angle between each group. A significant positive relationship was observed between intraocular pressure and the degree of pigmentation of the anterior chamber angle in both the PEX group and the pseudoexfoliation glaucoma group. The results of this study indicate that the amount of pigmentation and exfoliation material in the anterior segment significantly correlates with the level of IOP and possibly with the degree of trabecular dysfunction. It seems that for clear identification of PEX and pseudoexfoliation glaucoma factors, clinical assessment appears to be insufficient.

  5. Gonial angle growth patterns according to age and gender.

    Science.gov (United States)

    Larrazabal-Moron, Carolina; Sanchis-Gimeno, Juan A

    2018-01-01

    Currently there are controversial results about gender and age differences in human gonial angle values. In this context we aimed to ascertain the gender and age differences in the gonial angle values of young Caucasian Mediterranean subjects. We tested the hypothesis of a relation between the gonial angle values and the gender and age of the subjects by means of a prospective study involving 266 subjects. Panoramic radiographs (Cranex Novus ® , XMIND Novus ® Soredex, France) were carried out in order to measure the gonial angle values. We found significant differences between females and males in the subgroups aged ≤10years old (128.6±3.4 vs 126.8±4.5, p=0.017), 16-20 years old (119.1±5.6 vs 122.3±7.7, p=0.011), 21-25 years old (117.6±5.2 vs 120.8±7.0, p=0.016) and 26-30 years old (117.5±5.4 vs 120.6±5.4, p=0.019) but not in the subgroup aged 11-15 years old (123.4±5.2 vs 123.5±5.4, p=0.927). A significant negative correlation was found between age and gonial angle values (r=-0.365, page have significantly higher values than males. The angle values decreased until the age of 11-15 years of age when there were no significant gender differences. Thus, the males aged over 16 years old presented significantly higher values than the females. The decrease in gonial angle values seems to slow or stop from 21 years onwards. Knowledge of the pattern differences will serve for age and gender determination when analyzing human remains. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Reliability of the ATD Angle in Dermatoglyphic Analysis.

    Science.gov (United States)

    Brunson, Emily K; Hohnan, Darryl J; Giovas, Christina M

    2015-09-01

    The "ATD" angle is a dermatoglyphic trait formed by drawing lines between the triradii below the first and last digits and the most proximal triradius on the hypothenar region of the palm. This trait has been widely used in dermatoglyphic studies, but several researchers have questioned its utility, specifically whether or not it can be measured reliably. The purpose of this research was to examine the measurement reliability of this trait. Finger and palm prints were taken using the carbon paper and tape method from the right and left hands of 100 individuals. Each "ATD" angle was read twice, at different times, by Reader A, using a goniometer and a magnifying glass, and three times by a Reader B, using Adobe Photoshop. Inter-class correlation coefficients were estimated for the intra- and inter-reader measurements of the "ATD" angles. Reader A was able to quantify ATD angles on 149 out of 200 prints (74.5%), and Reader B on 179 out of 200 prints (89.5%). Both readers agreed on whether an angle existed on a print 89.8% of the time for the right hand and 78.0% for the left. Intra-reader correlations were 0.97 or greater for both readers. Inter-reader correlations for "ATD" angles measured by both readers ranged from 0.92 to 0.96. These results suggest that the "ATD" angle can be measured reliably, and further imply that measurement using a software program may provide an advantage over other methods.

  7. Association of iris crypts with acute primary angle closure.

    Science.gov (United States)

    Koh, Victor; Chua, Jacqueline; Shi, Yuan; Thakku, Sri Gowtham; Lee, Ryan; Nongpiur, Monisha E; Baskaran, Mani; Kumar, Rajesh S; Perera, Shamira; Aung, Tin; Cheng, Ching-Yu

    2017-10-01

    To determine the relationship between iris surface features and acute primary angle closure (APAC) in eyes with angle closure. Case-control study involving Asian patients diagnosed with previous APAC, primary angle closure suspect (PACS), primary angle closure (PAC) and primary angle closure glaucoma (PACG) at an eye centre in Singapore between August 2012 and January 2015. Participants underwent ophthalmic examination and digital slit-lamp iris photography. Iris surface features were graded based on crypts, furrows and colour. Fellow eyes of APAC were compared with PACS and PAC/PACG eyes with regard to their iris surface features. Occurrence of APAC. A total of 309 patients (71 APAC, 139 PACS, 47 PAC and 52 PACG) were included (mean age: 67.7±7.2 years and 36.6% male). Compared with PACS, higher crypt grade was significantly associated with lower odds of APAC (OR=0.58 for one grade higher in crypt grade; p=0.027, adjusted for age, gender, ethnicity and pupil diameter). The results remained similar when compared with PAC/PACG group (OR=0.58 for one grade higher in crypt grade; p=0.043). We did not observe any significant associations between iris furrows or colour with presence of APAC. Our study comprising Asian eyes with angle closure suggests that the presence of a higher crypt grading may be protective for APAC. As such, assessing iris surface architecture for crypts could be a new measure for risk stratification of developing APAC in eyes with angle closure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. Uncertainty incorporated beam angle optimization for IMPT treatment planning.

    Science.gov (United States)

    Cao, Wenhua; Lim, Gino J; Lee, Andrew; Li, Yupeng; Liu, Wei; Ronald Zhu, X; Zhang, Xiaodong

    2012-08-01

    Beam angle optimization (BAO) by far remains an important and challenging problem in external beam radiation therapy treatment planning. Conventional BAO algorithms discussed in previous studies all focused on photon-based therapies. Impact of BAO on proton therapy is important while proton therapy increasingly receives great interests. This study focuses on potential benefits of BAO on intensity-modulated proton therapy (IMPT) that recently began available to clinical cancer treatment. The authors have developed a novel uncertainty incorporated BAO algorithm for IMPT treatment planning in that IMPT plan quality is highly sensitive to uncertainties such as proton range and setup errors. A linear programming was used to optimize robust intensity maps to scenario-based uncertainties for an incident beam angle configuration. Unlike conventional intensity-modulated radiation therapy with photons (IMXT), the search space for IMPT treatment beam angles may be relatively small but optimizing an IMPT plan may require higher computational costs due to larger data size. Therefore, a deterministic local neighborhood search algorithm that only needs a very limited number of plan objective evaluations was used to optimize beam angles in IMPT treatment planning. Three prostate cancer cases and two skull base chordoma cases were studied to demonstrate the dosimetric advantages and robustness of optimized beam angles from the proposed BAO algorithm. Two- to four-beam plans were optimized for prostate cases, and two- and three-beam plans were optimized for skull base cases. By comparing plans with conventional two parallel-opposed angles, all plans with optimized angles consistently improved sparing at organs at risks, i.e., rectum and femoral heads for prostate, brainstem for skull base, in either nominal dose distribution or uncertainty-based dose distributions. The efficiency of the BAO algorithm was demonstrated by comparing it with alternative methods including simulated

  9. Small angle x-ray scattering and its applications

    International Nuclear Information System (INIS)

    Buckely, C.E.

    2002-01-01

    Full text: Small angle X-ray scattering is an excellent technique to characterise inhomogeneities in materials in the size range from 1 nm - several hundred nm. Ultra small angle X-ray scattering has extended this size range out to 20 μm. SAXS is due to the electron density difference between the matrix and the inhomogeneity. SAXS and small angle neutron scattering have been successfully used to characterise colloidal particles in solution, colloidal powders, macromolecules, glasses and a wide range of solids such as metals, alloys, and natural and synthetic high polymers. Small angle scattering and complementary techniques, such as transmission and scanning electron microscopy are a powerful combination for the investigation of submicron particles. This talk will introduce the small angle scattering technique and its applications, and will also describe the new Nanostar SAXS instrument in the Department of Applied Physics at Curtin University that has been purchased through a 2001 Australian Research Council research infrastructure and equipment fund (2001 ARC RIEF) grant. Copyright (2002) Australian X-ray Analytical Association Inc

  10. Frequency of unerupted mandibular third molar in mandibular angle fractures

    International Nuclear Information System (INIS)

    Abbasi, M.M.; Abbas, I.; Abbas, I.; Khan, N.; Hameed, H.; Zulfiqar, K.

    2012-01-01

    Background: Fractures of the mandibular angle are common and comprise 31% of all mandibular fractures. Multiple recent studies report a 2-3 fold increased risk for mandibular angle fractures when un-erupted mandibular third molars are present. The objective of this study was to assess the frequency of un-erupted mandibular third molar in mandibular angle fractures. Methods: This cross sectional study was conducted at the Department of Oral and Maxillofacial Surgery, Ayub Medical College, Abbottabad from April to October 2009. One hundred and two patients were included both from the outdoor and ward on consecutive non-probability sampling base. Data were recorded on a structured Performa and analysed using SPSS-16. Results: A hemi-mandible containing un-erupted mandibular third molar was seen to have a 1.41 times the risk of mandibular angle fracture then a hemi-mandible containing an erupted mandibular third molar. Conclusion: The presence of unerupted mandibular third molar is associated with an increased risk for mandibular angle fracture. (author)

  11. Discriminating electromagnetic radiation based on angle of incidence

    Science.gov (United States)

    Hamam, Rafif E.; Bermel, Peter; Celanovic, Ivan; Soljacic, Marin; Yeng, Adrian Y. X.; Ghebrebrhan, Michael; Joannopoulos, John D.

    2015-06-16

    The present invention provides systems, articles, and methods for discriminating electromagnetic radiation based upon the angle of incidence of the electromagnetic radiation. In some cases, the materials and systems described herein can be capable of inhibiting reflection of electromagnetic radiation (e.g., the materials and systems can be capable of transmitting and/or absorbing electromagnetic radiation) within a given range of angles of incidence at a first incident surface, while substantially reflecting electromagnetic radiation outside the range of angles of incidence at a second incident surface (which can be the same as or different from the first incident surface). A photonic material comprising a plurality of periodically occurring separate domains can be used, in some cases, to selectively transmit and/or selectively absorb one portion of incoming electromagnetic radiation while reflecting another portion of incoming electromagnetic radiation, based upon the angle of incidence. In some embodiments, one domain of the photonic material can include an isotropic dielectric function, while another domain of the photonic material can include an anisotropic dielectric function. In some instances, one domain of the photonic material can include an isotropic magnetic permeability, while another domain of the photonic material can include an anisotropic magnetic permeability. In some embodiments, non-photonic materials (e.g., materials with relatively large scale features) can be used to selectively absorb incoming electromagnetic radiation based on angle of incidence.

  12. Normal Foot and Ankle Radiographic Angles, Measurements, and Reference Points.

    Science.gov (United States)

    Lamm, Bradley M; Stasko, Paul A; Gesheff, Martin G; Bhave, Anil

    2016-01-01

    The limb deformity-based principles originate from a standard set of lower extremity radiographic angles and reference points. Objective radiographic measures are the building blocks for surgical planning. Critical preoperative planning and intraoperative and postoperative evaluation of radiographs are essential for proper deformity planning and correction of all foot and ankle cases. A total of 33 angles and reference points were measured on 24 healthy feet. The radiographic measurements were performed on standard weightbearing anteroposterior, lateral, and axial views of the right foot. A total of 4 measurements were made from the axial view, 12 from the lateral view, and 17 from the anteroposterior view. All angles were measured by both senior authors twice, independent of each other. The radiographic angles and measurements presented in the present study demonstrate a comprehensive and useful set of standard angles, measures, and reference points that can be used in clinical and perioperative evaluation of the foot and ankle. The standard radiographic measures presented in the present study provide the foundation for understanding the osseous foot and ankle position in a normal population. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  13. Rotating Shaft Tilt Angle Measurement Using an Inclinometer

    Science.gov (United States)

    Luo, Jun; Wang, Zhiqian; Shen, Chengwu; Wen, Zhuoman; Liu, Shaojin; Cai, Sheng; Li, Jianrong

    2015-10-01

    This paper describes a novel measurement method to accurately measure the rotating shaft tilt angle of rotating machine for alignment or compensation using a dual-axis inclinometer. A model of the rotating shaft tilt angle measurement is established using a dual-axis inclinometer based on the designed mechanical structure, and the calculation equation between the rotating shaft tilt angle and the inclinometer axes outputs is derived under the condition that the inclinometer axes are perpendicular to the rotating shaft. The reversal measurement method is applied to decrease the effect of inclinometer drifts caused by temperature, to eliminate inclinometer and rotating shaft mechanical error and inclinometer systematic error to attain high measurement accuracy. The uncertainty estimation shows that the accuracy of rotating shaft tilt angle measurement depends mainly on the inclinometer uncertainty and its uncertainty is almost the same as the inclinometer uncertainty in the simulation. The experimental results indicate that measurement time is 4 seconds; the range of rotating shaft tilt angle is 0.002° and its standard deviation is 0.0006° using NS-5/P2 inclinometer, whose precision and resolution are ±0.01° and 0.0005°, respectively.

  14. Rotating Shaft Tilt Angle Measurement Using an Inclinometer

    Directory of Open Access Journals (Sweden)

    Luo Jun

    2015-10-01

    Full Text Available This paper describes a novel measurement method to accurately measure the rotating shaft tilt angle of rotating machine for alignment or compensation using a dual-axis inclinometer. A model of the rotating shaft tilt angle measurement is established using a dual-axis inclinometer based on the designed mechanical structure, and the calculation equation between the rotating shaft tilt angle and the inclinometer axes outputs is derived under the condition that the inclinometer axes are perpendicular to the rotating shaft. The reversal measurement method is applied to decrease the effect of inclinometer drifts caused by temperature, to eliminate inclinometer and rotating shaft mechanical error and inclinometer systematic error to attain high measurement accuracy. The uncertainty estimation shows that the accuracy of rotating shaft tilt angle measurement depends mainly on the inclinometer uncertainty and its uncertainty is almost the same as the inclinometer uncertainty in the simulation. The experimental results indicate that measurement time is 4 seconds; the range of rotating shaft tilt angle is 0.002° and its standard deviation is 0.0006° using NS-5/P2 inclinometer, whose precision and resolution are ±0.01° and 0.0005°, respectively.

  15. Citalopram associated with acute angle-closure glaucoma: case report

    Directory of Open Access Journals (Sweden)

    Hassan Sabit

    2005-10-01

    Full Text Available Abstract Background Acute angle-closure glaucoma is a rare complication in patients receiving anti-depressant treatment. In the following case, we report the development of acute angle closure glaucoma in a patient who overdosed on Citalopram, an antidepressant, and discuss the possible etiological mechanisms for the condition. Case presentation We report a 54 year old, Caucasian lady, with depression and alcohol dependence syndrome, who developed acute angle-closure glaucoma after an overdose of Citalopram, along with alcohol. She was treated with medications and had bilateral Yag laser iridotomies to correct the glaucoma and has made complete recovery. In this case, the underlying cause for glaucoma appears to be related to the ingestion of Citalopram. Conclusion The patho-physiological basis for acute angle closure glaucoma in relation to antidepressant medications remains unclear. The authors suggest Citalopram may have a direct action on the Iris or Ciliary body muscle through serotonergic or anti-cholinergic mechanisms or both. This case highlights the importance of the awareness of the underlying risks, which may predispose an individual to develop acute angle-closure glaucoma, and reminds the clinicians the significance of history taking and examination of the eye before and after starting anti-depressants. This area needs to be further researched.

  16. Estimation of Upper Limb Joint Angle Using Surface EMG Signal

    Directory of Open Access Journals (Sweden)

    Yee Mon Aung

    2013-10-01

    Full Text Available In the development of robot-assisted rehabilitation systems for upper limb rehabilitation therapy, human electromyogram (EMG is widely used due to its ability to detect the user intended motion. EMG is one kind of biological signal that can be recorded to evaluate the performance of skeletal muscles by means of a sensor electrode. Based on recorded EMG signals, user intended motion could be extracted via estimation of joint torque, force or angle. Therefore, this estimation becomes one of the most important factors to achieve accurate user intended motion. In this paper, an upper limb joint angle estimation methodology is proposed. A back propagation neural network (BPNN is developed to estimate the shoulder and elbow joint angles from the recorded EMG signals. A Virtual Human Model (VHM is also developed and integrated with BPNN to perform the simulation of the estimated angle. The relationships between sEMG signals and upper limb movements are observed in this paper. The effectiveness of our developments is evaluated with four healthy subjects and a VHM simulation. The results show that the methodology can be used in the estimation of joint angles based on EMG.

  17. Determination of the Contact Angle Based on the Casimir Effect

    Science.gov (United States)

    Mazuruk, Konstantin; Volz, Martin P.

    2015-01-01

    On a macroscopic scale, a nonreactive liquid partially covering a homogeneous solid surface will intersect the solid at an angle called the contact angle. For molten metals and semiconductors, the contact angle is materially dependent upon both the solid and liquid and typical values fall in the range 80-170 deg, depending on the crucible material. On a microscopic scale, there does not exist a precise and sharp contact angle but rather the liquid and solid surfaces merge smoothly and continuously. Consider the example of the so called detached Bridgman crystal growth process. In this technique, a small gap is formed between the growing crystal and the crucible. At the crystal/melt interface, a meniscus ring is formed. Its width can be in the range of a few micrometers, approaching a microscopic scale. It then becomes questionable to describe the shape of this meniscus by the contact angle. A more advanced treatment of the interface is needed and here we propose such a refined model. The interaction of the liquid surface with the solid can be calculated by considering two forces: a short-range repulsive force and a longer range (up to a few micrometers) Casimir or van der Waals force.

  18. Small-angle neutron-scattering experiment, (2)

    International Nuclear Information System (INIS)

    Niimura, Nobuo; Kaji, Harumi.

    1983-01-01

    Elementary explanation is given to the experiment on the small angle scattering using neutrons having long wave-length (3-12A), continued from the previous report. Two types of the apparatus for small angle neutron scattering experiment are described. The first is angle dispersion type, which uses the neutron beam from research reactors, and the second is wavelength dispersion type, which uses pulsed cold neutron sources. The principles of these experiments are explained. Especially the wavelength dispersion is described in detail. The apparatus in the booster facility at the Institute for High Energy Physics is shown as an example for the latter type. The two-dimensional position sensitive detector, which is essential for angle dispersion type, is also used for the wavelength dispersion type, and its data processing is also described. In the small angle neutron scattering experiment for the studies on the structure of living body substances, the techniques that should be taken into account in common are discussed; the proportion of D 2 O-H 2 O in solvent, the measurable range of Q, the size of specimens, the correction of incident neutron spectra, and the analysis of measured data. (Asami, T.)

  19. Development of spin echo small angle neutron scattering

    International Nuclear Information System (INIS)

    Bouwman, W.G.; Uca, O.; Van Oossanen, M.; Kraan, W.H.; Rekveldt, M.T.

    1999-01-01

    A novel kind of small angle neutron scattering (SANS) instrument is being built, based on the Larmor precession of polarised neutrons in a magnetic field. A spin echo of the polarised neutrons is used to detect the scattering. The basis of this instrument is a symmetric set-up with a spin flipper in the centre, which creates a spin echo, even with a divergent beam. The precession regions on either side of the spin flipper are shaped such to produce a very sensitive relation between the vertical angle of the neutron path and the total precession angle on one side. Any SANS of a sample placed in the instrument changes the symmetry of the neutron path and therefore decreases the echo. This amounts to measuring only the difference of the incoming and outgoing angle. This gives a huge increase in intensity of the signal with respect to conventional SANS in which both incoming and outgoing angle are defined. Magnetised foils, which rotate the neutron spin between being parallel to the magnetic field and perpendicular to the field are used to start or terminate the precession. With a preliminary set-up the first spin echo SANS signal have been measured. A full correlation function in samples over distances from 5 to 1000 nm is expected to be measured in some minutes. (author)

  20. Contact angles of nanodrops on chemically rough surfaces.

    Science.gov (United States)

    Berim, Gersh O; Ruckenstein, Eli

    2009-08-18

    The experimental observations of Gao and McCarthy [Gao, L.; McCarthy, T. Langmuir, 2007, 23, 3762] that only the interfacial area near the leading edges of the drop on physically smooth but chemically rough solid surfaces affects the contact angle and that most of the contact area has no effect is checked for nanodrops on the basis of a density functional theory. The contact angle was calculated for three cases: (i) the leading edges of the drops are located on much higher or (ii) much lower hydrophobic surfaces than the remaining surface beneath the drop; (iii) the surface is composed of a periodic array of two kinds of stripelike solid plates. In the first two cases, if the distance between the leading edges and the region which has higher or lower hydrophobicity is sufficiently large, there is agreement with the experiments mentioned. However, when those distances are sufficiently small, the internal part affects the value of the angle. In the third case, we found that the internal part always affects the wetting angle. All these peculiarities, as well as the contact angle hysteresis, can be explained by accounting for the local conditions in the vicinity of the leading edges of the drop.

  1. Contact angles of wetting and water stability of soil structure

    Science.gov (United States)

    Kholodov, V. A.; Yaroslavtseva, N. V.; Yashin, M. A.; Frid, A. S.; Lazarev, V. I.; Tyugai, Z. N.; Milanovskiy, E. Yu.

    2015-06-01

    From the soddy-podzolic soils and typical chernozems of different texture and land use, dry 3-1 mm aggregates were isolated and sieved in water. As a result, water-stable aggregates and water-unstable particles composing dry 3-1 mm aggregates were obtained. These preparations were ground, and contact angles of wetting were determined by the static sessile drop method. The angles varied from 11° to 85°. In most cases, the values of the angles for the water-stable aggregates significantly exceeded those for the water-unstable components. In terms of carbon content in structural units, there was no correlation between these parameters. When analyzing the soil varieties separately, the significant positive correlation between the carbon content and contact angle of aggregates was revealed only for the loamy-clayey typical chernozem. Based on the multivariate analysis of variance, the value of contact wetting angle was shown to be determined by the structural units belonging to water-stable or water-unstable components of macroaggregates and by the land use type. In addition, along with these parameters, the texture has an indirect effect.

  2. Numerical study of hub taper angle on podded propeller performance

    International Nuclear Information System (INIS)

    Islam, M.F.; Veitch, B.; Bose, N.; Liu, P.

    2005-01-01

    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)

  3. Analysis of the changing Solar Radiation Angle on Hainan Island

    Directory of Open Access Journals (Sweden)

    Ge Zhiwu

    2017-01-01

    Full Text Available As the only tropical provinces in China, Hainan province has advantageous geographical location, and abundant solar energy resources. But because of Local ideas and habits, especially the lack of theoretical research on local solar resources, development and application of solar energy in Hainan is almost blank. In this paper, we studied the variation regularity of sunlight angle on Hainan tropical island, analyzed the revolution and rotation of the earth, and the change rule of sunlight angle caused by the sun’s movement between the tropic of cancer and the tropic of capricorn, deduced the change rule of sunlight angle in the spring equinox, the autumnal equinox, summer solstice and winter solstice day, and got the movement rules of solar elevation angle throughout the year. Theoretic analysis is consistent with field measurement results. These rules are of importance and can effectively guide the local People’s daily life and production, such as the reasonable layout of the buildings, floor distance between different heights of buildings, the direction of the lighting windows of tall buildings, installation angle of photovoltaic panels, and other similar solar energy absorbing and conversion equipment.

  4. Scattering-angle based filtering of the waveform inversion gradients

    KAUST Repository

    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.

  5. Angle-selective all-dielectric Huygens’ metasurfaces

    Science.gov (United States)

    Arslan, D.; Chong, K. E.; Miroshnichenko, A. E.; Choi, D.-Y.; Neshev, D. N.; Pertsch, T.; Kivshar, Y. S.; Staude, I.

    2017-11-01

    We experimentally and numerically study the angularly resolved transmission properties of dielectric metasurfaces consisting of silicon nanodisks which support electric and magnetic dipolar Mie-type resonances in the near-infrared spectral range. First, we concentrate on Huygens’ metasurfaces which are characterised by a spectral overlap of the fundamental electric and magnetic dipole resonances of the silicon nanodisks at normal incidence. Huygens’ metasurfaces exhibit a high transmitted intensity over the spectral width of the resonances due to impedance matching, while the transmitted phase shows a variation of 2π as the wavelength is swept across the width of the resonances. We observe that the transmittance of the Huygens’ metasurfaces depends on the incidence angle and is sensitive to polarisation for non-normal incidence. As the incidence angle is increased starting from normal incidence, the two dipole resonances are shifted out of the spectral overlap and the resonant features appear as pronounced transmittance minima. Next, we consider a metasurface with an increased nanodisk radius as compared to the Huygens’ metasurface, which supports spectrally separate electric and magnetic dipole resonances at normal incidence. We show that for TM polarisation, we can shift the resonances of this metasurface into spectral overlap and regain the high resonant transmittance characteristic of Huygens’ metasurfaces at a particular incidence angle. Furthermore, both metasurfaces are demonstrated to reject all TM polarised light incident under angles other than the design overlap angle at their respective operation frequency. Our experimental observations are in good qualitative agreement with numerical calculations.

  6. Scanning Angle Raman spectroscopy in polymer thin film characterization

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Vy H.T. [Iowa State Univ., Ames, IA (United States)

    2015-12-19

    The focus of this thesis is the application of Raman spectroscopy for the characterization of thin polymer films. Chapter 1 provides background information and motivation, including the fundamentals of Raman spectroscopy for chemical analysis, scanning angle Raman scattering and scanning angle Raman scattering for applications in thin polymer film characterization. Chapter 2 represents a published manuscript that focuses on the application of scanning angle Raman spectroscopy for the analysis of submicron thin films with a description of methodology for measuring the film thickness and location of an interface between two polymer layers. Chapter 3 provides an outlook and future directions for the work outlined in this thesis. Appendix A, contains a published manuscript that outlines the use of Raman spectroscopy to aid in the synthesis of heterogeneous catalytic systems. Appendix B and C contain published manuscripts that set a foundation for the work presented in Chapter 2.

  7. Angle-of-attack estimation for analysis of CAT encounters

    Science.gov (United States)

    Bach, R. E., Jr.; Parks, E. K.

    1985-01-01

    Recent studies of clear-air turbulence (CAT) encounters involving wide-body airliners have been based upon flight-path wind estimates made by analyzing digital flight-data-recorder (DFDR) records and radar records. Such estimates require a time history of the aircraft angle of attack, a record that is not usually included in the DFDR measurement set. This paper describes a method for reconstructing angle of attack that utilizes available flight record and aircraft-specific information associated with an aerodynamic model of the lift coefficient. Results from two wide-body incidents in which vane measurements of angle of attack were recorded show good agreement between measured and calculated time histories. This research has been performed in cooperation with the National Transportation Safety Board to provide a better understanding of the CAT phenomenon.

  8. Perception of angle in visual categorization by pigeons (Columba livia.

    Directory of Open Access Journals (Sweden)

    Walter T. Herbranson

    2017-08-01

    Full Text Available Pigeons are capable of learning to categorize stimuli based on visual features, and often reach levels of accuracy comparable with humans. Nevertheless, recent research has suggested that the cognitive processes behind categorization in pigeons and humans may not always be the same. Pigeons learned a categorization task in which they categorized either Shepard circles varying in size and orientation of a radial line (stimuli that are frequently used in research on human categorization, or moving dots varying in speed and direction of travel (stimuli that have been successfully used to study pigeon categorization. Even though categories were balanced so that the angles of orientation of Shepard circles matched the directions of travel for moving dots, birds failed to learn categories based on the former but not the latter. Results suggest that information about angle as a direction of travel may be more important for pigeons than information about angle of orientation.

  9. Flow tilt angles near forest edges - Part 2: Lidar anemometry

    DEFF Research Database (Denmark)

    Dellwik, Ebba; Mann, Jakob; Bingöl, Ferhat

    2010-01-01

    A novel way of estimating near-surface mean flow tilt angles from ground based Doppler lidar measurements is presented. The results are compared with traditional mast based in-situ sonic anemometry. The tilt angle assessed with the lidar is based on 10 or 30 min mean values of the velocity field......) a fetch-limited beech forest site taken at 48–175 m a.g.l. (above ground level), (2) a reference site in flat agricultural terrain and (3) a second reference site in complex terrain are presented. The method to derive flow tilt angles and mean vertical velocities from lidar has several advantages compared...... alignment error at a multitude of heights. Disadvantages with estimating vertical velocities from a lidar compared to mast-based measurements are potentially slightly increased levels of statistical errors due to limited sampling time, because the sampling is disjunct, and a requirement for homogeneous flow...

  10. Towards the Extraction of the CKM Angle $\\gamma$

    CERN Document Server

    Fleischer, Robert

    1999-01-01

    The determination of the angle $\\gamma$ of the unitarity triangle of the CKM matrix is regarded as a challenge for future $B$-physics experiments. In this context, the decays $B^\\pm\\to \\pi^\\pm K$ and $B_d\\to\\pi^\\mp K^\\pm$, which were observed by the CLEO collaboration last year, received a lot of interest in the literature. After a general parametrization of their decay amplitudes, strategies to constrain and determine the CKM angle $\\gamma$ with the help of the corresponding observables are reviewed. The theoretical accuracy of these methods is limited by certain rescattering and electroweak penguin effects. It is emphasized that the rescattering processes can be included in the bounds on decays, and steps towards the control of electroweak penguins are pointed out. Moreover, strategies to probe the CKM angle $\\gamma$ with the help of $B_s\\to

  11. The National Facility for Small-Angle Neutron Scattering

    International Nuclear Information System (INIS)

    Koehler, W.C.

    1986-01-01

    On this occasion honoring Professor C.G.Shull, the 30-m small-angle neutron scattering (SANS) instrument of the National Center for Small-Angle Scattering Research (NCSASR) will have been in routine user-mode operation for five years. Professor Shull served the Center as chairman of its first Advisory Committee and in that capacity contributed his expertise to the construction phase of the 30-m machine and to the formulation of operating policy. He has had a long and varied interest in the scientific application of small-angle scattering of X-rays and of neutrons. It is a pleasure for me to dedicate this review to him on his 70th birthday. (orig.)

  12. Small Angle Scattering in Neutron Imaging—A Review

    Directory of Open Access Journals (Sweden)

    Markus Strobl

    2017-12-01

    Full Text Available Conventional neutron imaging utilizes the beam attenuation caused by scattering and absorption through the materials constituting an object in order to investigate its macroscopic inner structure. Small angle scattering has basically no impact on such images under the geometrical conditions applied. Nevertheless, in recent years different experimental methods have been developed in neutron imaging, which enable to not only generate contrast based on neutrons scattered to very small angles, but to map and quantify small angle scattering with the spatial resolution of neutron imaging. This enables neutron imaging to access length scales which are not directly resolved in real space and to investigate bulk structures and processes spanning multiple length scales from centimeters to tens of nanometers.

  13. Optimization of sharp and viewing-angle-independent structural color.

    Science.gov (United States)

    Hsu, Chia Wei; Miller, Owen D; Johnson, Steven G; Soljačić, Marin

    2015-04-06

    Structural coloration produces some of the most brilliant colors in nature and has many applications. Motivated by the recently proposed transparent displays that are based on wavelength-selective scattering, here we consider the new problem of transparent structural color, where objects are transparent under omnidirectional broad-band illumination but scatter strongly with a directional narrow-band light source. Transparent structural color requires two competing properties, narrow bandwidth and broad viewing angle, that have not been demonstrated simultaneously previously. Here, we use numerical optimization to discover geometries where a sharp 7% bandwidth in scattering is achieved, yet the peak wavelength varies less than 1%, and the peak height and peak width vary less than 6% over broad viewing angles (0-90°) under a 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.

  14. An introduction to small-angle neutron scattering

    International Nuclear Information System (INIS)

    Windsor, C.G.

    1988-01-01

    Neutron and X-ray small-angle scattering provide, along with electron microscopy and diffraction, the principal techniques for the microscopic characterization of materials. Neutron, X-ray and electron beams each have quite different properties. In fact, each has unique advantages. The penetration of neutrons through most materials is responsible for many applications. The ever-increasing intensity of available X-ray beams is opening new fields. The advantage of electron beams is their ability to work in both real and reciprocal space. The problems of transforming the results of an experiment in reciprocal space to give an interpretation in real space are central to small-angle scattering, and are discussed. Several examples will be given of the successful use of small-angle neutron scattering applied to problems where other techniques have failed to make a decisive contribution. (orig.)

  15. Effect of inlet cone pipe angle in catalytic converter

    Science.gov (United States)

    Amira Zainal, Nurul; Farhain Azmi, Ezzatul; Arifin Samad, Mohd

    2018-03-01

    The catalytic converter shows significant consequence to improve the performance of the vehicle start from it launched into production. Nowadays, the geometric design of the catalytic converter has become critical to avoid the behavior of backpressure in the exhaust system. The backpressure essentially reduced the performance of vehicles and increased the fuel consumption gradually. Consequently, this study aims to design various models of catalytic converter and optimize the volume of fluid flow inside the catalytic converter by changing the inlet cone pipe angles. Three different geometry angles of the inlet cone pipe of the catalytic converter were assessed. The model is simulated in Solidworks software to determine the optimum geometric design of the catalytic converter. The result showed that by decreasing the divergence angle of inlet cone pipe will upsurge the performance of the catalytic converter.

  16. Standing phase angle reduction for power system restoration

    Energy Technology Data Exchange (ETDEWEB)

    Hazarika, D. [Assam Engineering College (India). Electrical Engineering Dept.; Sinha, A.K. [IIT Khargpur (India). Electrical Engineering Dept.

    1998-01-01

    The paper describes a methodology for the reduction of standing phase angle (SPA) difference between two buses of a power system, which is essential before interconnecting a line between two buses. This problem is encountered normally during restoration operations of a power system. For this purpose, the standing phase angle difference between two specific buses is represented in terms of sensitivity factors associated with the change in real power injections at the buses. To arrive at the desired standing phase angle difference between two buses, the modified contribution at generation/load buses have been evaluated based on 'higher the sensitivity higher the participation' logic. This methodology acts as a direct help to reduce excessive SPA difference between two buses to an acceptable limit, which otherwise requires regulation of various generation levels on a trial and error basis. (author)

  17. Bilateral Acute Angle-closure after Intraocular Surgery.

    Science.gov (United States)

    Hoskens, Kirsten; Pinto, Luis Abegão; Vandewalle, Evelien; Verdonk, Nancy; Stalmans, Ingeborg

    2014-01-01

    We report the case of a 75-year-old woman who developed an acute bilateral angle-closure associated with choroidal effusion a day after an uneventful cataract surgery. The same patient had undergone a similarly uneventful cataract surgery two weeks before, under the same protocol, with no postoperative complication in the other eye. Medical treatment, including the use of oral sulfamide-related drugs (acetazolamide), topical beta-blockers and steroids led to a gradual decrease in intraocular pressure (IOP) and choroidal effusion. Despite initial reports suggesting a link between sulfamide-exposure and these rare forms of angle-closure, our report would suggest a more complex pathophysiology behind this intriguing phenomenon. How to cite this article: Hoskens K, Pinto LA, Vandewalle E, Verdonk N, Stalmans I. Bilateral Acute Angle-closure after Intraocular Surgery. J Curr Glaucoma Pract 2014;8(3):113-114.

  18. An optimal algorithm for computing angle-constrained spanners

    OpenAIRE

    Paz Carmi; Michiel Smid

    2012-01-01

    Let S be a set of n points in Rd and let t>1 be a real number. A graph G=(S,E) is called a t-spanner for S, if for any two points p and q in S, the shortest-path distance in G between p andq is at most t|pq|, where |pq| denotes the Euclidean distance between p and q. The graph G is called θ-angle-constrained, if any two distinct edges sharing an endpoint make an angle of at least θ. It is shown that, for any θ with 0<θ<π/3, a θ-angle-constrained t-spanner can be computed in O(nlog n)...

  19. Surface tension and contact angles of molten cadmium telluride

    Science.gov (United States)

    Balasubramanian, R.; Wilcox, W. R.

    1990-01-01

    The surface tension and contact angle of molten cadmium telluride (CdTe) were measured as a function of temperature by the sessile drop technique. A FORTRAN code was developed to calculate the surface tension of sessile drops, with the contact angle ranging from O to 180°. The wetting of cadmium telluride melt was studied on different surfaces. The surface tension of cadmium telluride was about 160 ±5 dynes · cm-1[1.6 m-1] at the melting point of 1093°C. The contact angle of CdTe melt was about 65° on a quartz optical flat, 75° on commercial fused quartz, and 125° on boron nitride coated quartz.

  20. Cancer of the colon spleen angle. Presentation of a case

    International Nuclear Information System (INIS)

    Martinez Sanchez, Yariana; De la Rosa Perez, Nereida; Barcelo Casanova, Renato E

    2010-01-01

    The colon cancer is currently an important public health problem in developed countries. It is the fourth most common cancer in the world. We report the case of a 65-years-old, black, female patient, assisting our consultation with dyspeptic disturbances as the unique symptom, without known risk factors. We indicated a colon by enema and a distal narrowing was observed at the colon spleen angle, at the same zone of the physiologic narrowing at that level. A colonoscopy was carried out diagnosing a left colon tumor near the spleen angle. It was operated with segmental resection of the spleen angle and a biopsy was made. Pathologic anatomy informed a well-differentiated colon adenocarcinoma

  1. Wide steering angle microscanner based on curved surface

    Science.gov (United States)

    Sabry, Yasser; Khalil, Diaa; Saadany, Bassam; Bourouina, Tarik

    2013-03-01

    Intensive industrial and academic research is oriented towards the design and fabrication of optical beam steering systems based on MEMS technology. In most of these systems, the scanning is achieved by rotating a flat micromirror around a central axis in which the main challenge is achieving a wide mirror rotation angle. In this work, a novel method of optical beam scanning based on reflection from a curved surface is presented. The scanning occurs when the optical axis of the curved surface is displaced with respect to the optical axis of the incident beam. To overcome the possible deformation of the spot with the scanning angle, the curved surface is designed with a specific aspherical profile. Moreover, the scanning exhibits a more linearized scanning angle-displacement relation than the conventional spherical profile. The presented scanner is fabricated using DRIE technology on an SOI wafer. The curved surface (reflector) is metalized and attached to a comb-drive actuator fabricated in the same lithography step. A single-mode fiber, behaving as a Gaussian beam source, is positioned on the substrate facing the mirror. The reflected optical beam angle and spotsize in the far field is recorded versus the relative shift between the fiber and the curved mirror. The spot size is plotted versus the scanning angle and a scanning spot size uniformity of about +/-10% is obtained for optical deflection angles up to 100 degrees. As the optical beam is propagating parallel to the wafer substrate, a completely integrated laser scanner can be achieved with filters and actuators self-aligned on the same chip that allows low cost and mass production of this important product.

  2. Contact Angles and Surface Tension of Germanium-Silicon Melts

    Science.gov (United States)

    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.

  3. Angles of total shifts and angles of maxumum crop during development of faces diagonal to seam strike directions

    Directory of Open Access Journals (Sweden)

    Н. А. Колесник

    2017-06-01

    Full Text Available When predicting deformations and determining measures to protect underworked objects, angular parameters are used: the boundary angles, the angles of total shift, the angle of maximum crop. The values of these angular parameters are given in the normative documents, but only for sections across and along the strike of the formation. However, at present, longwall face mining is mainly being carried out along a diagonal direction to the strike of the formation. In connection with this, the determination of the values of the angular parameters for such conditions is a topical task.The method of determination and the analytical dependences of the angles of total shifts and angles of maximum crop in sections of the longitudinal and transverse axes of coal-mining faces developed along diagonal directions to the strike of the formation are proposed. These angular parameters are used for prognosis of deformations of the earth's surface and for determining the characteristic zones of influence of mine workings on the local places.

  4. Alpha emitters activity measurement using the defined solid angle method

    International Nuclear Information System (INIS)

    Blanchis, P.

    1983-01-01

    The defined solid angle counting method can reach a very high accuracy, specially for heavy ions as alpha particles emitted by a radioactive source. The activity measurement of such sources with a relative uncertainty of the order of 0.01% is investigated. Such an accuracy is available only under suitable conditions: the radiation emitted by the source must be isotropic and all the particles emitted in the effective solid angle must be detected. The efficiency detection value must be equal to unity and phenomena such as absorption or scattering must be null. It is shown that corrections often become necessary. All parameters which can influence the measurements are studied [fr

  5. DESIGN OF ILC EXTRACTION LINE FOR 20 MRAD CROSSING ANGLE

    International Nuclear Information System (INIS)

    Nosochkov, Y.; Moffeit, K.; Seryi, A.; Woods, M.; SLAC; Arnold, R.; Massachusetts U., Amherst; Oliver, W.; Tufts U.; Parker, B.; Brookhaven; Torrence, E.; Oregon U.

    2005-01-01

    One of the two ILC Interaction Regions will have a large horizontal crossing angle which would allow to extract the spent beams in a separate beam line. In this paper, the extraction line design for 20 mrad crossing angle is presented. This beam line transports the primary e + /e - and beamstrahlung photon beams from the IP to a common dump, and includes diagnostic section for energy and polarization measurements. The optics is designed for a large energy acceptance to minimize losses in the low energy tail of the disrupted beam. The extraction optics, diagnostic instrumentation and particle tracking simulations are described

  6. On the Euler angles for SU(N)

    Energy Technology Data Exchange (ETDEWEB)

    Cerchiai, Bianca L; Bertini, S.; Cacciatori, Sergio L.

    2005-10-20

    In this paper we reconsider the problem of the Euler parametrization for the unitary groups. After constructing the generic group element in terms of generalized angles, we compute the invariant measure on SU(N) and then we determine the full range of the parameters, using both topological and geometrical methods. In particular, we show that the given parametrization realizes the group SU(N+1) as a fibration of U(N) over the complex projective space CP{sup n}. This justifies the interpretation of the parameters as generalized Euler angles.

  7. Small angle elastic scattering of electrons by noble gas atoms

    International Nuclear Information System (INIS)

    Wagenaar, R.W.

    1984-01-01

    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.)

  8. Vowel Formants and Angle Measurements in Diachronic Sociophonetic Studies

    DEFF Research Database (Denmark)

    Fabricius, Anne

    2007-01-01

    This paper examines vowel formant data from a corpus of recordings of male speakers of RP born during the course of the twentieth century. It compares average formant positions in the F1/F2 plane for the short vowel FOOT in juxtaposition with LOT (for this Keyword notation see Wells [12......]). The relative positions of the two vowels are represented by a single numerical value, which is the calculated angle from LOT to FOOT relative to the vertical. Changing angle values between the early and the later part of the twentieth century reflect a diachronic process of FOOT-fronting and unrounding which...

  9. Quantum ring models and action-angle variables

    OpenAIRE

    Bellucci, Stefano; Nersessian, Armen; Saghatelian, Armen; Yeghikyan, Vahagn

    2010-01-01

    We suggest to use the action-angle variables for the study of properties of (quasi)particles in quantum rings. For this purpose we present the action-angle variables for three two-dimensional singular oscillator systems. The first one is the usual (Euclidean) singular oscillator, which plays the role of the confinement potential for the quantum ring. We also propose two singular spherical oscillator models for the role of the confinement system for the spherical ring. The first one is based o...

  10. Oral Rehabilitation of a Patient with Cerebellopontine Angle Epidermoid Cyst

    Directory of Open Access Journals (Sweden)

    Amin Nourizadeh

    2015-01-01

    Full Text Available Epidermoid cysts are rare congenital tumors of the central nervous system (CNS, histologically benign and slow- growing lesions. Their frequency among primitive intracranial tumors is about 1% and they account for 40% of all intracranial epidermoid cysts of the cerebellopontine angle (CPA; the most common symptom which brings about difficulties in oral rehabilitation of these patients is facial weakness which diversely affects impression processes and use of prosthesis. We report the oral rehabilitation of a patient with a cerebellopontine angle epidermoid cyst using neutral zone approach.   Keywords: Soft tissue thickness; Facial reconstruction; Cone Beam Computed Tomography

  11. Measurement of the CKM angle $\\gamma$ at LHCb

    CERN Multimedia

    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.

  12. 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.

  13. High contact angle hysteresis of superhydrophobic surfaces: Hydrophobic defects

    Science.gov (United States)

    Chang, Feng-Ming; Hong, Siang-Jie; Sheng, Yu-Jane; Tsao, Heng-Kwong

    2009-08-01

    A typical superhydrophobic surface is essentially nonadhesive and exhibits very low water contact angle (CA) hysteresis, so-called Lotus effect. However, leaves of some plants such as scallion and garlic with an advancing angle exceeding 150° show very serious CA hysteresis. Although surface roughness and epicuticular wax can explain the very high advancing CA, our analysis indicates that the unusual hydrophobic defect, diallyl disulfide, is the key element responsible for contact line pinning on allium leaves. After smearing diallyl disulfide on an extended polytetrafluoroethylene (PTFE) film, which is originally absent of CA hysteresis, the surface remains superhydrophobic but becomes highly adhesive.

  14. Research progress on related genes for primary open angle glaucoma

    Directory of Open Access Journals (Sweden)

    Ailijiang·Aierken

    2014-04-01

    Full Text Available Primary open angle glaucoma(POAGis the main cause of blindness with visual field damage and optic nerve degeneration. In recent years, a lot of researches have been done, showing that genetic factors and gene mutation play an important role in POAG. There are more than 20 related POAG genes. Now we will review the related genes of POAG, especially the well known causative genes of MYOC, OPTN, WDR36, and CAV1/CAV2, in terms of their locations, structures, research progress, et al, and provide a reference for genetic research in primary open-angle glaucoma.

  15. X-ray diffraction at Bragg angles around π/2

    International Nuclear Information System (INIS)

    Mayolo, C.M.G. de.

    1991-01-01

    X-ray diffraction at Bragg angles around π/2 is studied from the theoretical and experimental points of view. The proposed corrections to the dynamical theory in the θ β ≅ π/2 cases, has been reviewed showing the equivalence between two formalisms leading to a corrected expression for the dependence of the angular parameter y with the angle of incidence. An expression for y valid in the conventional and θ β ≅ π/2 cases has been obtained. A general expression for Bragg law and for energy resolution after a Bragg diffraction was also deduced. (author)

  16. Edge effects in angle-ply composite laminates

    Science.gov (United States)

    Hsu, P. W.; Herakovich, C. T.

    1977-01-01

    This paper presents the results of a zeroth-order solution for edge effects in angle-ply composite laminates obtained using perturbation techniques and a limiting free body approach. The general solution for edge effects in laminates of arbitrary angle ply is applied to the special case of a (+ or - 45)s graphite/epoxy laminate. Interlaminar stress distributions are obtained as a function of the laminate thickness-to-width ratio and compared to finite difference results. The solution predicts stable, continuous stress distributions, determines finite maximum tensile interlaminar normal stress and provides mathematical evidence for singular interlaminar shear stresses in (+ or - 45) graphite/epoxy laminates.

  17. The misalignment angle in vessel-mounted ADCP

    Directory of Open Access Journals (Sweden)

    Robert Osinski

    2000-09-01

    Full Text Available A description of the misalignment angle and the consequences if it occurs is given. It is shown that because of gyrocompass errors, the misalignment angle error a has to be computed for each cruise. A simple method of calibrating the acoustic Doppler current profiler (ADCP mounted on a vessel has been devised by fitting the cosinusoidal function. This is a post-processing method, suitable for calibrating previously collected data. Nevertheless, because of ADCP's constructional peculiarities, the procedure must be repeated for each cruise.

  18. Right-angled polyhedra and hyperbolic 3-manifolds

    Science.gov (United States)

    Vesnin, A. Yu.

    2017-04-01

    Hyperbolic 3-manifolds whose fundamental groups are subgroups of finite index in right-angled Coxeter groups are under consideration. The construction of such manifolds is associated with regular colourings of the faces of polyhedra and, in particular, with 4-colourings. The following questions are discussed: the structure of the set of right-angled polytopes in Lobachevskii space; examples of orientable and non-orientable manifolds, including the classical Löbell manifold constructed in 1931; connections between the Hamiltonian property of a polyhedron and the existence of hyperelliptic involutions of manifolds; the volumes and complexity of manifolds; isometry between hyperbolic manifolds constructed from 4-colourings. Bibliography: 89 titles.

  19. Small-angle neutron scattering in materials science

    International Nuclear Information System (INIS)

    Fratzl, P.

    1999-01-01

    Small-angle scattering (SAS) in an ideal tool for studying the structure of materials in the mesoscopic size range between 1 and about 100 nanometers. The basic principles of the method are reviewed, with particular emphasis on data evaluation and interpretation for isotropic as well as oriented or single-crystalline materials. Examples include metal alloys, composites and porous materials. The last section gives a comparison between the use of neutrons and (synchrotron) x-rays for small-angle scattering in materials physics. (author)

  20. Automatic learning-based beam angle selection for thoracic IMRT.

    Science.gov (United States)

    Amit, Guy; Purdie, Thomas G; Levinshtein, Alex; Hope, Andrew J; Lindsay, Patricia; Marshall, Andrea; Jaffray, David A; Pekar, Vladimir

    2015-04-01

    The treatment of thoracic cancer using external beam radiation requires an optimal selection of the radiation beam directions to ensure effective coverage of the target volume and to avoid unnecessary treatment of normal healthy tissues. Intensity modulated radiation therapy (IMRT) planning is a lengthy process, which requires the planner to iterate between choosing beam angles, specifying dose-volume objectives and executing IMRT optimization. In thorax treatment planning, where there are no class solutions for beam placement, beam angle selection is performed manually, based on the planner's clinical experience. The purpose of this work is to propose and study a computationally efficient framework that utilizes machine learning to automatically select treatment beam angles. Such a framework may be helpful for reducing the overall planning workload. The authors introduce an automated beam selection method, based on learning the relationships between beam angles and anatomical features. Using a large set of clinically approved IMRT plans, a random forest regression algorithm is trained to map a multitude of anatomical features into an individual beam score. An optimization scheme is then built to select and adjust the beam angles, considering the learned interbeam dependencies. The validity and quality of the automatically selected beams evaluated using the manually selected beams from the corresponding clinical plans as the ground truth. The analysis included 149 clinically approved thoracic IMRT plans. For a randomly selected test subset of 27 plans, IMRT plans were generated using automatically selected beams and compared to the clinical plans. The comparison of the predicted and the clinical beam angles demonstrated a good average correspondence between the two (angular distance 16.8° ± 10°, correlation 0.75 ± 0.2). The dose distributions of the semiautomatic and clinical plans were equivalent in terms of primary target volume coverage and organ at risk

  1. Effect of phacoemulsification on drainage angle status in angle closure eyes with or without extensive peripheral anterior synechiae.

    Science.gov (United States)

    Latifi, Golshan; Moghimi, Sasan; Eslami, Yadollah; Fakhraie, Ghasem; Zarei, Reza; Lin, Shan

    2013-01-21

    Purpose. To evaluate the anatomic effects of phacoemulsification on drainage angle status in primary angle closure glaucoma (PACG) using anterior segment optical coherence tomography (AS-OCT). Methods. A total of 62 eyes of 58 patients underwent cataract surgery in Farabi Rye Hospital, Tehran, Iran. Patients were examined postoperatively on day 1, week 1, and week 6. Indentation gonioscopy and AS-OCT were performed preoperatively and at 6 weeks after surgery. Main outcome measures were angle and anterior segment parameters by AS-OCT and amount of peripheral anterior synechiae (PAS) by gonioscopy. Thirty-five eyes had PAS =180 degrees (group 1) and 27 eyes had >180-degree synechial closure (group 2). Results. Mean age of the patients was 64.3±9.0 years. The mean extent of PAS was significantly reduced from 45.9 to 32.2 degrees (p180 degrees.

  2. Numerical simulation of the effects of variation of angle of attack and sweep angle on vortex breakdown over delta wings

    Science.gov (United States)

    Ekaterinaris, J. A.; Schiff, Lewis B.

    1990-01-01

    In the present investigation of the vortical flowfield structure over delta wings at high angles of attack, three-dimensional Navier-Stokes numerical simulations were conducted to predict the complex leeward flowfield characteristics; these encompass leading-edge separation, secondary separation, and vortex breakdown. Attention is given to the effect on solution accuracy of circumferential grid-resolution variations in the vicinity of the wing leading edge, and well as to the effect of turbulence modeling on the solutions. When a critical angle-of-attack was reached, bubble-type vortex breakdown was found. With further angle-of-attack increase, a change from bubble-type to spiral-type vortex breakdown was predicted by the numerical solution.

  3. Glacial Features (Point) - Quad 168 (EPPING, NH)

    Data.gov (United States)

    University of New Hampshire — The Glacial Features (Point) layer describes point features associated with surficial geology. These glacial features include, but are not limited to, delta forsets,...

  4. Clayton 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  5. Clayton 1:100000 Quad Hydrography DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  6. Jal 1:100000 Quad Hydrography DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  7. Jal 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  8. Springerville 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  9. Corona 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  10. Springer 1:100000 Quad Hydrography DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  11. Springer 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  12. Raton 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  13. Wilcox 1:100000 Quad Hydrography DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  14. Zuni 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  15. Albuquerque 1:100000 Quad Hydrography DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  16. Lordsburg 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  17. Socorro 1:100000 Quad Transportation DLGs

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related...

  18. Evaluation of anterior chamber angle under dark and light conditions in angle closure glaucoma: An anterior segment OCT study.

    Science.gov (United States)

    Masoodi, Habibeh; Jafarzadehpur, Ebrahim; Esmaeili, Alireza; Abolbashari, Fereshteh; Ahmadi Hosseini, Seyed Mahdi

    2014-08-01

    To evaluate changes of nasal and temporal anterior chamber angle (ACA) in subjects with angle closure glaucoma using Spectralis AS-OCT (SAS-OCT) under dark and light conditions. Based on dark-room gonioscopy, 24 subjects with open angles and 86 with narrow angles participated in this study. The nasal and temporal angle opening distance at 500 μm anterior to the scleral spur (AOD500), nasal and temporal ACA were measured using SAS-OCT in light and dark conditions. In 2 groups, ACA and AOD500 in nasal and temporal quadrants were significantly greater in light compared to dark (all with p=0.000). The AOD500 and ACA were significantly higher in nasal than temporal in measured conditions for 2 groups except the ACA and AOD500 of normal group measured in light. The difference between nasal and temporal in dark (29.07 ± 65.71 μm for AOD500 and 5.7 ± 4.07° for ACA) was greater than light (24.86 ± 79.85 μm for AOD500 and 2.09 ± 7.21° for ACA) condition. But the difference was only significant for ACA (p=0.000). The correlation analysis showed a negative correlation between AOD500 and pupil diameter in temporal and nasal quadrants (both with p=0.000). While temporal AOD500 difference correlated with spherical equivalent, temporal and asal gonioscopy, nasal AOD correlated with IOP, temporal and nasal gonioscopy. Clinically important changes in ACA structure could be detected with SAS-OCT in nasal and temporal quadrants under different illumination intensity. The results could help in improvement of examination condition for better and more accurate assessment of individuals with angle closure glaucoma. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  19. The Effects of Approach Angle and Rake Angle Due to Chatter Vibrations on Surface Roughness in Turning

    OpenAIRE

    NEŞELİ, Süleyman; YALDIZ, Süleyman

    2007-01-01

    In this study, the effect of the chatter vibrations depend on tool geometry on surface roughness in turning has been investigated. Machining process in universal lathe is carried out on AISI 1040 steel in dry cutting condition using various approaching/entering angles (60°, 75°, 90°) and rake angles (-3°,-6°,-9°) at depth of cut of 0.5 mm. During cutting processes, tool nose radius and tool overhang (tool noise of kept point distance) and cutting speed, feed rate and spindle speed as cutting ...

  20. small signal analysis of load angle governing and excitation control

    African Journals Online (AJOL)

    Dr Obe

    optimal value of regulator gain for damping as far as this study is concerned will be some value above 0.25. This is similar to the findings of Aldred and Shackshaft [2] using frequency response methods. Following as above for the same machine with excitation control only, but this time around, utilizing the load angle.