WorldWideScience

Sample records for streamwise lift distribution

  1. Analysis of the Effects of Streamwise Lift Distribution on Sonic Boom Signature

    Science.gov (United States)

    Yoo, Paul

    2013-01-01

    Investigation of sonic boom has been one of the major areas of study in aeronautics due to the benefits a low-boom aircraft has in both civilian and military applications. This work conducts a numerical analysis of the effects of streamwise lift distribution on the shock coalescence characteristics. A simple wing-canard-stabilator body model is used in the numerical simulation. The streamwise lift distribution is varied by fixing the canard at a deflection angle while trimming the aircraft with the wing and the stabilator at the desired lift coefficient. The lift and the pitching moment coefficients are computed using the Missile DATCOM v. 707. The flow field around the wing-canard- stabilator body model is resolved using the OVERFLOW-2 flow solver. Overset/ chimera grid topology is used to simplify the grid generation of various configurations representing different streamwise lift distributions. The numerical simulations are performed without viscosity unless it is required for numerical stability. All configurations are simulated at Mach 1.4, angle-of-attack of 1.50, lift coefficient of 0.05, and pitching moment coefficient of approximately 0. Four streamwise lift distribution configurations were tested.

  2. Eddy current distribution and lift force for finite MAGLEV strips

    Energy Technology Data Exchange (ETDEWEB)

    Atherton, D L; Eastham, A R; Fombrun, C; Chong, M

    1974-07-01

    The transverse distribution of induced eddy currents across a flat conducing strip of finite width, due to a rectangular dc magnet moving above it, was modelled experimentally, and was compared with that calculated for an infinite sheet. The electrodynamic suspension was simulated by means of a stationary ac-excited copper magnet suspended above an aluminum strip, and the induced surface current density was measured by a voltage pickup probe connected to a lock-in amplifier. The effect of reducing strip width is examined and shown to produce high current densities close to the edges. These results are related to the variation of lift force with strip width, determined by impedance modelling. A slight enhancement of lift is evident for intermediate strip widths.

  3. Computational Analysis of Powered Lift Augmentation for the LEAPTech Distributed Electric Propulsion Wing

    Science.gov (United States)

    Deere, Karen A.; Viken, Sally A.; Carter, Melissa B.; Viken, Jeffrey K.; Wiese, Michael R.; Farr, Norma L.

    2017-01-01

    A computational study of a distributed electric propulsion wing with a 40deg flap deflection has been completed using FUN3D. Two lift-augmentation power conditions were compared with the power-off configuration on the high-lift wing (40deg flap) at a 73 mph freestream flow and for a range of angles of attack from -5 degrees to 14 degrees. The computational study also included investigating the benefit of corotating versus counter-rotating propeller spin direction to powered-lift performance. The results indicate a large benefit in lift coefficient, over the entire range of angle of attack studied, by using corotating propellers that all spin counter to the wingtip vortex. For the landing condition, 73 mph, the unpowered 40deg flap configuration achieved a maximum lift coefficient of 2.3. With high-lift blowing the maximum lift coefficient increased to 5.61. Therefore, the lift augmentation is a factor of 2.4. Taking advantage of the fullspan lift augmentation at similar performance means that a wing powered with the distributed electric propulsion system requires only 42 percent of the wing area of the unpowered wing. This technology will allow wings to be 'cruise optimized', meaning that they will be able to fly closer to maximum lift over drag conditions at the design cruise speed of the aircraft.

  4. Comparative Study of Wing Lift Distribution Analysis for High Altitude Long Endurance (HALE) Unmaned Aerial Vehicle

    Science.gov (United States)

    Silitonga, Faber Y.; Agoes Moelyadi, M.

    2018-04-01

    The development of High Altitude Long Endurance (HALE) Unmanned Aerial Vehicle (UAV) has been emerged for both civil and military purposes. Its ability of operating in high altitude with long endurance is important in supporting maritime applications.Preliminary analysis of HALE UAV lift distribution of the wing presented to give decisive consideration for its early development. Ensuring that the generated lift is enough to compensate its own weight. Therotical approach using Pradtl’s non-linear lifting line theory will be compared with modern numerical approach using Computational Fluid Dynamics (CFD). Results of wing lift distribution calculated from both methods will be compared to study the reliability of it. HALE UAV ITB has high aspect ratio wing and will be analyze at cruise flight condition. The result indicates difference between Non-linear Lifting Line and CFD method.

  5. High-Lift Propeller System Configuration Selection for NASA's SCEPTOR Distributed Electric Propulsion Flight Demonstrator

    Science.gov (United States)

    Patterson, Michael D.; Derlaga, Joseph M.; Borer, Nicholas K.

    2016-01-01

    Although the primary function of propellers is typically to produce thrust, aircraft equipped with distributed electric propulsion (DEP) may utilize propellers whose main purpose is to act as a form of high-lift device. These \\high-lift propellers" can be placed upstream of wing such that, when the higher-velocity ow in the propellers' slipstreams interacts with the wing, the lift is increased. This technique is a main design feature of a new NASA advanced design project called Scalable Convergent Electric Propulsion Technology Operations Research (SCEPTOR). The goal of the SCEPTOR project is design, build, and y a DEP aircraft to demonstrate that such an aircraft can be much more ecient than conventional designs. This paper provides details into the high-lift propeller system con guration selection for the SCEPTOR ight demonstrator. The methods used in the high-lift propeller system conceptual design and the tradeo s considered in selecting the number of propellers are discussed.

  6. Normal loads program for aerodynamic lifting surface theory. [evaluation of spanwise and chordwise loading distributions

    Science.gov (United States)

    Medan, R. T.; Ray, K. S.

    1974-01-01

    A description of and users manual are presented for a U.S.A. FORTRAN 4 computer program which evaluates spanwise and chordwise loading distributions, lift coefficient, pitching moment coefficient, and other stability derivatives for thin wings in linearized, steady, subsonic flow. The program is based on a kernel function method lifting surface theory and is applicable to a large class of planforms including asymmetrical ones and ones with mixed straight and curved edges.

  7. High-Lift Propeller Noise Prediction for a Distributed Electric Propulsion Flight Demonstrator

    Science.gov (United States)

    Nark, Douglas M.; Buning, Pieter G.; Jones, William T.; Derlaga, Joseph M.

    2017-01-01

    Over the past several years, the use of electric propulsion technologies within aircraft design has received increased attention. The characteristics of electric propulsion systems open up new areas of the aircraft design space, such as the use of distributed electric propulsion (DEP). In this approach, electric motors are placed in many different locations to achieve increased efficiency through integration of the propulsion system with the airframe. Under a project called Scalable Convergent Electric Propulsion Technology Operations Research (SCEPTOR), NASA is designing a flight demonstrator aircraft that employs many "high-lift propellers" distributed upstream of the wing leading edge and two cruise propellers (one at each wingtip). As the high-lift propellers are operational at low flight speeds (take-off/approach flight conditions), the impact of the DEP configuration on the aircraft noise signature is also an important design consideration. This paper describes efforts toward the development of a mulit-fidelity aerodynamic and acoustic methodology for DEP high-lift propeller aeroacoustic modeling. Specifically, the PAS, OVERFLOW 2, and FUN3D codes are used to predict the aerodynamic performance of a baseline high-lift propeller blade set. Blade surface pressure results from the aerodynamic predictions are then used with PSU-WOPWOP and the F1A module of the NASA second generation Aircraft NOise Prediction Program to predict the isolated high-lift propeller noise source. Comparisons of predictions indicate that general trends related to angle of attack effects at the blade passage frequency are captured well with the various codes. Results for higher harmonics of the blade passage frequency appear consistent for the CFD based methods. Conversely, evidence of the need for a study of the effects of increased azimuthal grid resolution on the PAS based results is indicated and will be pursued in future work. Overall, the results indicate that the computational

  8. On generating counter-rotating streamwise vortices

    KAUST Repository

    Winoto, S H

    2015-09-23

    Counter-rotating streamwise vortices are known to enhance the heat transfer rate from a surface and also to improve the aerodynamic performance of an aerofoil. In this paper, some methods to generate such counter-rotating vortices using different methods or physical conditions will be briefly considered and discussed.

  9. On generating counter-rotating streamwise vortices

    KAUST Repository

    Winoto, S H; Mitsudharmadi, Hatsari; Budiman, A C; Hasheminejad, S M; Nadesan, T; Tandiono; Low, H T; Lee, T S

    2015-01-01

    Counter-rotating streamwise vortices are known to enhance the heat transfer rate from a surface and also to improve the aerodynamic performance of an aerofoil. In this paper, some methods to generate such counter-rotating vortices using different methods or physical conditions will be briefly considered and discussed.

  10. The Circulation Distribution on the Lifting Line for a Given Extracted Power

    Directory of Open Access Journals (Sweden)

    Ali Helali

    2012-01-01

    Full Text Available Presently, there exist few numerical methods which treat the inverse problem for the determination of the geometry of wind turbine blades. In this work, authors intend to solve the inverse optimum project for horizontal axis wind turbine in which the selection of the circulation distribution is obtained by resolving two variational problems: the first consists in sorting the circulation distribution on the lifting line, which, for a given power extracted by the wind turbine, minimizes the loses due to the induced velocity. In the second, the optimal circulation distribution is selected such that the kinetic energy of the wind downstream of the rotor disc is minimum, when the energy extracted by the wind turbine for one rotating period is imposed. A code has been developed which incorporates the real pitch of the helicoidal vortex wake. Very promising results have been obtained: the circulation distribution for a given extracted power and the chord lengths distribution law along the blade span.

  11. Streamwise-body-force-model for rapid simulation combining internal and external flow fields

    Directory of Open Access Journals (Sweden)

    Cui Rong

    2016-10-01

    Full Text Available A streamwise-body-force-model (SBFM is developed and applied in the overall flow simulation for the distributed propulsion system, combining internal and external flow fields. In view of axial stage effects, fan or compressor effects could be simplified as body forces along the streamline. These body forces which are functions of local parameters could be added as source terms in Navier-Stokes equations to replace solid boundary conditions of blades and hubs. The validation of SBFM with uniform inlet and distortion inlet of compressors shows that pressure performance characteristics agree well with experimental data. A three-dimensional simulation of the integration configuration, via a blended wing body aircraft with a distributed propulsion system using the SBFM, has been completed. Lift coefficient and drag coefficient agree well with wind tunnel test results. Results show that to reach the goal of rapid integrated simulation combining internal and external flow fields, the computational fluid dynamics method based on SBFM is reasonable.

  12. Dynamic lift measurements on a FX79W151A airfoil via pressure distribution on the wind tunnel walls

    Energy Technology Data Exchange (ETDEWEB)

    Wolken-Moehlmann, Gerrit [ForWind - Center for Wind Energy Research, University of Oldenburg (Germany); Knebel, Pascal [ForWind - Center for Wind Energy Research, University of Oldenburg (Germany); Barth, Stephan [ECN Wind Energy, Energy research Centre of the (Netherlands); Peinke, Joachim [ForWind - Center for Wind Energy Research, University of Oldenburg (Germany)

    2007-07-15

    We report on an experimental setup for measurements of dynamic stall for airfoils via the pressure distribution over wind tunnel walls. This measuring technique, hitherto used for lift measurements under static conditions, is also an adequate method for dynamic conditions until stall occurs. A step motor is used, allowing for sinusoidal as well as non-sinusoidal and stochastic pitching to simulate fast fluctuating flow conditions. Measurements with sinusoidal pitching and constant angular velocities were done and show dynamic stall characteristics. Under dynamic stall conditions, maximum lift coefficients were up to 80% higher than the maximum for static lift.

  13. Annoyance to Noise Produced by a Distributed Electric Propulsion High-Lift System

    Science.gov (United States)

    Rizzi, Stephen A.; Palumbo, Daniel L.; Rathsam, Jonathan; Christian, Andrew; Rafaelof, Menachem

    2017-01-01

    A psychoacoustic test was performed using simulated sounds from a distributed electric propulsion aircraft concept to help understand factors associated with human annoyance. A design space spanning the number of high-lift leading edge propellers and their relative operating speeds, inclusive of time varying effects associated with motor controller error and atmospheric turbulence, was considered. It was found that the mean annoyance response varies in a statistically significant manner with the number of propellers and with the inclusion of time varying effects, but does not differ significantly with the relative RPM between propellers. An annoyance model was developed, inclusive of confidence intervals, using the noise metrics of loudness, roughness, and tonality as predictors.

  14. Perceived Annoyance to Noise Produced by a Distributed Electric Propulsion High Lift System

    Science.gov (United States)

    Palumbo, Dan; Rathsam, Jonathan; Christian, Andrew; Rafaelof, Menachem

    2016-01-01

    Results of a psychoacoustic test performed to understand the relative annoyance to noise produced by several configurations of a distributed electric propulsion high lift system are given. It is found that the number of propellers in the system is a major factor in annoyance perception. This is an intuitive result as annoyance increases, in general, with frequency, and, the blade passage frequency of the propellers increases with the number of propellers. Additionally, the data indicate that having some variation in the blade passage frequency from propeller-to-propeller is beneficial as it reduces the high tonality generated when all the propellers are spinning in synchrony at the same speed. The propellers can be set to spin at different speeds, but it was found that allowing the motor controllers to drift within 1% of nominal settings produced the best results (lowest overall annoyance). The methodology employed has been demonstrated to be effective in providing timely feedback to designers in the early stages of design development.

  15. A proof of the theorem regarding the distribution of lift over the span for minimum induced drag

    Science.gov (United States)

    Durand, W F

    1931-01-01

    The proof of the theorem that the elliptical distribution of lift over the span is that which will give rise to the minimum induced drag has been given in a variety of ways, generally speaking too difficult to be readily followed by the graduate of the average good technical school of the present day. In the form of proof this report makes an effort to bring the matter more readily within the grasp of this class of readers.

  16. Tornado lift

    OpenAIRE

    Ivanchin, Alexander

    2010-01-01

    It is shown that one of the causes for tornado is Tornado Lift. At increasing vortex diameter its kinetic energy decreases to keep the moment of momentum constant. A kinetic energy gradient of such vortex is Tornado Lift. Evaluation shows that contribution of Tornado Lift in air lifting in a tornado is comparable to buoyancy according to the order of magnitude.

  17. Reynolds stress analysis of EMHD-controlled wall turbulence. Part I. Streamwise forcing

    International Nuclear Information System (INIS)

    Crawford, C.H.; Karniadakis, G.E.

    1997-01-01

    In this work we investigate numerically turbulent flow of low electrical conductivity fluid subject to electro-magnetic (EMHD) forcing. The configuration is similar to the one considered in the experimental work of Henoch and Stace [Phys. Fluids 7, 1371 (1995)] but in a channel geometry. The lower wall of the channel is covered with alternating streamwise electrodes and magnets to create a Lorentz force in the positive streamwise direction. Two cases are considered in detail corresponding to interaction parameter values of 0.4 (case 1) and 0.1 (case 2). The effect of switching off and on the electrodes is also studied for the two cases. At the Reynolds number considered (Re τ ∼200), a drag increase was obtained for all cases, in agreement with the experiments of Henoch and Stace. A Reynolds stress analysis was performed based on a new decomposition of the gradients normal to the wall of the Reynolds stress -u'v'. It was found that the vortex stretching term w'w 2 ' and the spanwise variation of the stress component u'w' are responsible for the drag increase. More specifically, the term ∂(u'w')/∂x 3 is associated with secondary vortical motions in the near-wall and becomes large and positive for large shear stress in regions where fluid is moving toward the wall. In contrast, negative values are associated with regions of lower shear where fluid is being lifted away from the wall. Unlike the unperturbed flow, in the controlled flow high speed near-wall streamwise jets are present (case 1) even in the time-averaged fields. Other changes in turbulence structure are quantified using streak spacing, vortex lines, vorticity quadrant analysis, and plots of the rms value of the vorticity angle. copyright 1997 American Institute of Physics

  18. Streamwise vortices destabilize swimming bluegill sunfish (Lepomis macrochirus).

    Science.gov (United States)

    Maia, Anabela; Sheltzer, Alex P; Tytell, Eric D

    2015-03-01

    In their natural environment, fish must swim stably through unsteady flows and vortices, including vertical vortices, typically shed by posts in a flow, horizontal cross-flow vortices, often produced by a step or a waterfall in a stream, and streamwise vortices, where the axis of rotation is aligned with the direction of the flow. Streamwise vortices are commonly shed by bluff bodies in streams and by ships' propellers and axial turbines, but we know little about their effects on fish. Here, we describe how bluegill sunfish use more energy and are destabilized more often in flow with strong streamwise vorticity. The vortices were created inside a sealed flow tank by an array of four turbines with similar diameter to the experimental fish. We measured oxygen consumption for seven sunfish swimming at 1.5 body lengths (BL) s(-1) with the turbines rotating at 2 Hz and with the turbines off (control). Simultaneously, we filmed the fish ventrally and recorded the fraction of time spent maneuvering side-to-side and accelerating forward. Separately, we also recorded lateral and ventral video for a combination of swimming speeds (0.5, 1.5 and 2.5 BL s(-1)) and turbine speeds (0, 1, 2 and 3 Hz), immediately after turning the turbines on and 10 min later to test for accommodation. Bluegill sunfish are negatively affected by streamwise vorticity. Spills (loss of heading), maneuvers and accelerations were more frequent when the turbines were on than in the control treatment. These unsteady behaviors, particularly acceleration, correlated with an increase in oxygen consumption in the vortex flow. Bluegill sunfish are generally fast to recover from roll perturbations and do so by moving their pectoral fins. The frequency of spills decreased after the turbines had run for 10 min, but was still markedly higher than in the control, showing that fish partially adapt to streamwise vorticity, but not completely. Coping with streamwise vorticity may be an important energetic

  19. Effects of streamwise vortex breakdown on supersonic combustion.

    Science.gov (United States)

    Hiejima, Toshihiko

    2016-04-01

    This paper presents a numerical simulation study of the combustion structure of streamwise vortex breakdown at Mach number 2.48. Hydrogen fuel is injected into a combustor at sonic speed from the rear of a hypermixer strut that can generate streamwise vortices. The results show that the burning behavior is enhanced at the points of the shock waves that are incident on the vortex and therefore the vortex breakdown in the subsonic region occurs due to combustion. The breakdown domain in the mainstream is found to form a flame-holding region suited to combustion and to lead to a stable combustion field with detached flames. In this way, streamwise vortex breakdown has an essential role in combustion enhancement and the formation of flames that hold under supersonic inflow conditions. Finally, the combustion property defined here is shown to coincide with the produced-water mass flow. This property shows that the amount of combustion is saturated at equivalence ratios over 0.4, although there is a slight increase beyond 1.

  20. Breast lift

    Science.gov (United States)

    ... and areola may be moved. Sometimes, women have breast augmentation (enlargement with implants) when they have a breast lift. Why the ... MD, FACS, general surgery practice specializing in breast cancer, Virginia Mason Medical Center, Seattle, WA. Also reviewed ...

  1. Lift enhancement by trapped vortex

    Science.gov (United States)

    Rossow, Vernon J.

    1992-01-01

    The viewgraphs and discussion of lift enhancement by trapped vortex are provided. Efforts are continuously being made to find simple ways to convert wings of aircraft from an efficient cruise configuration to one that develops the high lift needed during landing and takeoff. The high-lift configurations studied here consist of conventional airfoils with a trapped vortex over the upper surface. The vortex is trapped by one or two vertical fences that serve as barriers to the oncoming stream and as reflection planes for the vortex and the sink that form a separation bubble on top of the airfoil. Since the full three-dimensional unsteady flow problem over the wing of an aircraft is so complicated that it is hard to get an understanding of the principles that govern the vortex trapping process, the analysis is restricted here to the flow field illustrated in the first slide. It is assumed that the flow field between the two end plates approximates a streamwise strip of the flow over a wing. The flow between the endplates and about the airfoil consists of a spanwise vortex located between the suction orifices in the endplates. The spanwise fence or spoiler located near the nose of the airfoil serves to form a separated flow region and a shear layer. The vorticity in the shear layer is concentrated into the vortex by withdrawal of fluid at the suction orifices. As the strength of the vortex increases with time, it eventually dominates the flow in the separated region so that a shear or vertical layer is no longer shed from the tip of the fence. At that point, the vortex strength is fixed and its location is such that all of the velocity contributions at its center sum to zero thereby making it an equilibrium point for the vortex. The results of a theoretical analysis of such an idealized flow field are described.

  2. Streamwise counter-rotating vortices generated by triangular leading edge pattern in flat plate boundary layer

    KAUST Repository

    Hasheminejad, S. M.; Mitsudharmadi, Hatsari; Winoto, S. H.; Lua, K. B.; Low, H. T.

    2016-01-01

    A series of flow visualizations were conducted to qualitatively study the development of streamwise counter-rotating vortices over a flat plate induced by triangular patterns at the leading edge of a flat plate. The experiments were carried out

  3. Study on process design of partially-balanced, hydraulically lifting vertical ship lift

    Science.gov (United States)

    Xin, Shen; Xiaofeng, Xu; Lu, Zhang; Bing, Zhu; Fei, Li

    2017-11-01

    The hub ship lift in Panjin is the first navigation structure in China for the link between the inland and open seas, which adopts a novel partially-balanced, hydraulically lifting ship lift; it can meet such requirements as fast and sharp water level change in open sea, large draft of a yacht, and launching of a ship reception chamber; its balancing weight system can effectively reduce the load of the primary lifting cylinder, and optimize the force distribution of the ship reception chamber. The paper provides an introduction to main equipment, basic principles, main features and system composition of a ship lift. The unique power system and balancing system of the completed ship lift has offered some experience for the construction of the tourism-type ship lifts with a lower lifting height.

  4. Mass elevation and lee effects markedly lift the elevational distribution of ground beetles in the Himalaya-Tibet orogen.

    Science.gov (United States)

    Schmidt, Joachim; Böhner, Jürgen; Brandl, Roland; Opgenoorth, Lars

    2017-01-01

    Mass elevation and lee effects markedly influence snow lines and tree lines in high mountain systems. However, their impact on other phenomena or groups of organisms has not yet been quantified. Here we quantitatively studied their influence in the Himalaya-Tibet orogen on the distribution of ground beetles as model organisms, specifically whether the ground beetle distribution increases from the outer to the inner parts of the orogen, against latitudinal effects. We also tested whether July temperature and solar radiation are predictors of the beetle's elevational distribution ranges. Finally, we discussed the general importance of these effects for the distributional and evolutionary history of the biota of High Asia. We modelled spatially explicit estimates of variables characterizing temperature and solar radiation and correlated the variables with the respective lower elevational range of 118 species of ground beetles from 76 high-alpine locations. Both July temperature and solar radiation significantly positively correlated with the elevational ranges of high-alpine beetles. Against the latitudinal trend, the median elevation of the respective species distributions increased by 800 m from the Himalayan south face north to the Transhimalaya. Our results indicate that an increase in seasonal temperature due to mass elevation and lee effects substantially impact the regional distribution patterns of alpine ground beetles of the Himalaya-Tibet orogen and are likely to affect also other soil biota there and in mountain ranges worldwide. Since these effects must have changed during orogenesis, their potential impact must be considered when biogeographic scenarios based on geological models are derived. As this has not been the practice, we believe that large biases likely exist in many paleoecological and evolutionary studies dealing with the biota from the Himalaya-Tibet orogen and mountain ranges worldwide.

  5. Instantaneous fluctuation velocity and skewness distributions upstream of transition onset

    International Nuclear Information System (INIS)

    Hernon, D.; Walsh, E.J.; McEligot, D.M.

    2007-01-01

    The development of streamwise orientated disturbances through the boundary layer thickness prior to transition onset for zero-pressure gradient boundary layer flow under the influence %Tu = 4.2 is presented. The analysis concentrates on the development of the maximum positive and negative of the fluctuation velocity in order to gain further insight into the transition process. The average location of the peak negative fluctuation velocity over a range of Reynolds numbers was measured in the upper portion of the boundary layer at y/δ ∼ 0.6, whereas the location of the peak positive value was measured at y/δ ∼ 0.3. The disturbance magnitude of the negative fluctuation velocity increased beyond that of the positive as transition onset approached. The distribution and disturbance magnitude of the maximum positive and negative fluctuation velocities indicate that the initiation of transition may occur on the low-speed components of the flow that are lifted up to the upper region of the boundary layer. This is in qualitative agreement with recent direct numerical simulations on the breakdown of the flow on the lifted low-speed streaks near the boundary layer edge. The results presented in this investigation also demonstrate the increased physical insight gained by examining the distributions of the maximum positive and negative of the streamwise fluctuation velocity component associated with the low- and high-speed streaks, compared to time-averaged values, in determining what structures cause the breakdown to turbulence

  6. A new technique for dynamic load distribution when two manipulators mutually lift a rigid object. Part 1, The proposed technique

    Energy Technology Data Exchange (ETDEWEB)

    Unseren, M.A.

    1994-04-01

    A general framework for solving the dynamic load distribution when two manipulators hold a rigid object is proposed. The underspecified problem of solving for the contact forces and torques based on the object`s equations of motion is transformed into a well specified problem. This is accomplished by augmenting the object`s equations of motion with additional equations which relate a new vector variable quantifying the internal contact force and torque degrees of freedom (DOF) as a linear function of the contact forces and torques. The resulting augmented system yields a well specified solution for the contact forces and torques in which they are separated into their motion inducing and internal components. A particular solution is suggested which enables the designer to conveniently specify what portion of the payload`s mass each manipulator is to bear. It is also shown that the results of the previous work are just a special case of the general load distribution framework described here.

  7. Lift truck safety review

    International Nuclear Information System (INIS)

    Cadwallader, L.C.

    1997-03-01

    This report presents safety information about powered industrial trucks. The basic lift truck, the counterbalanced sit down rider truck, is the primary focus of the report. Lift truck engineering is briefly described, then a hazard analysis is performed on the lift truck. Case histories and accident statistics are also given. Rules and regulations about lift trucks, such as the US Occupational Safety an Health Administration laws and the Underwriter's Laboratories standards, are discussed. Safety issues with lift trucks are reviewed, and lift truck safety and reliability are discussed. Some quantitative reliability values are given

  8. Lift truck safety review

    Energy Technology Data Exchange (ETDEWEB)

    Cadwallader, L.C.

    1997-03-01

    This report presents safety information about powered industrial trucks. The basic lift truck, the counterbalanced sit down rider truck, is the primary focus of the report. Lift truck engineering is briefly described, then a hazard analysis is performed on the lift truck. Case histories and accident statistics are also given. Rules and regulations about lift trucks, such as the US Occupational Safety an Health Administration laws and the Underwriter`s Laboratories standards, are discussed. Safety issues with lift trucks are reviewed, and lift truck safety and reliability are discussed. Some quantitative reliability values are given.

  9. How Do Wings Generate Lift?

    Indian Academy of Sciences (India)

    So how do you go about teaching them something new? By mix- ing what they know with .... the viscous terms to the Euler equations increases the order of the ... such a strange result, one can use this pressure distribution and calculate the lift ...

  10. A review of a method for dynamic load distribution, dynamical modeling, and explicit internal force control when two manipulators mutually lift and transport a rigid body object

    International Nuclear Information System (INIS)

    Unseren, M.A.

    1997-01-01

    The paper reviews a method for modeling and controlling two serial link manipulators which mutually lift and transport a rigid body object in a three dimensional workspace. A new vector variable is introduced which parameterizes the internal contact force controlled degrees of freedom. A technique for dynamically distributing the payload between the manipulators is suggested which yields a family of solutions for the contact forces and torques the manipulators impart to the object. A set of rigid body kinematic constraints which restrict the values of the joint velocities of both manipulators is derived. A rigid body dynamical model for the closed chain system is first developed in the joint space. The model is obtained by generalizing the previous methods for deriving the model. The joint velocity and acceleration variables in the model are expressed in terms of independent pseudovariables. The pseudospace model is transformed to obtain reduced order equations of motion and a separate set of equations governing the internal components of the contact forces and torques. A theoretic control architecture is suggested which explicitly decouples the two sets of equations comprising the model. The controller enables the designer to develop independent, non-interacting control laws for the position control and internal force control of the system

  11. A review of a method for dynamic load distribution, dynamical modeling, and explicit internal force control when two manipulators mutually lift and transport a rigid body object

    Energy Technology Data Exchange (ETDEWEB)

    Unseren, M.A.

    1997-04-20

    The paper reviews a method for modeling and controlling two serial link manipulators which mutually lift and transport a rigid body object in a three dimensional workspace. A new vector variable is introduced which parameterizes the internal contact force controlled degrees of freedom. A technique for dynamically distributing the payload between the manipulators is suggested which yields a family of solutions for the contact forces and torques the manipulators impart to the object. A set of rigid body kinematic constraints which restrict the values of the joint velocities of both manipulators is derived. A rigid body dynamical model for the closed chain system is first developed in the joint space. The model is obtained by generalizing the previous methods for deriving the model. The joint velocity and acceleration variables in the model are expressed in terms of independent pseudovariables. The pseudospace model is transformed to obtain reduced order equations of motion and a separate set of equations governing the internal components of the contact forces and torques. A theoretic control architecture is suggested which explicitly decouples the two sets of equations comprising the model. The controller enables the designer to develop independent, non-interacting control laws for the position control and internal force control of the system.

  12. Lift scheduling organization : Lift Concept for Lemminkainen

    OpenAIRE

    Mingalimov, Iurii

    2015-01-01

    The purpose of the work was to make a simple schedule for the main contractors and clients to check and control workflow connected with lifts. It gathers works with electricity, construction, engineering networks, installing equipment and commissioning works. The schedule was carried out during working on the building site Aino in Saint Petersburg in Lemminkӓinen. The duration of work was 5 months. The lift concept in Lemminkӓinen is very well controlled in comparison with other buil...

  13. Criterion for vortex breakdown on shock wave and streamwise vortex interactions.

    Science.gov (United States)

    Hiejima, Toshihiko

    2014-05-01

    The interactions between supersonic streamwise vortices and oblique shock waves are theoretically and numerically investigated by three-dimensional (3D) Navier-Stokes equations. Based on the two inequalities, a criterion for shock-induced breakdown of the streamwise vortex is proposed. The simple breakdown condition depends on the Mach number, the swirl number, the velocity deficit, and the shock angle. According to the proposed criterion, the breakdown region expands as the Mach number increases. In numerical simulations, vortex breakdown appeared under conditions of multiple pressure increases and the helicity disappeared behind the oblique shock wave along the line of the vortex center. The numerical results are consistent with the predicted breakdown condition at Mach numbers 2.0 and 3.0. This study also found that the axial velocity deficit is important for classifying the breakdown configuration.

  14. The influence of streamwise vortices on turbulent heat transfer in rectangular ducts with various aspect ratios

    International Nuclear Information System (INIS)

    Choi, Hang Seok; Park, Tae Seon

    2013-01-01

    Highlights: ► With changing aspect ratio, the effect of secondary flows on the turbulent heat transfer is scrutinized by a LES. ► The conditional sampling technique of instantaneous near-wall streamwise vortices is developed. ► Clockwise and counter-clockwise rotating streamwise vortices are sampled and discussed with the wall heat transfer. ► The hot-sweep motions of CW and CCW vortices clearly appear with increasing aspect ratio. -- Abstract: The effect of aspect ratio of rectangular duct on the turbulent flow and heat transfer is very important for its engineering applications. But the turbulent thermal fields have not been fundamentally scrutinized in spite of its engineering significance especially for cooling device. Hence, in the present study, large eddy simulation is applied to the turbulent flow and heat transfer in rectangular ducts with varying aspect ratio. The turbulent statistics of the flow and thermal quantities are calculated and the characteristics of wall Nusselt number are investigated for each rectangular duct. Especially, to scrutinize near-wall streamwise vortices, a conditional sampling technique is developed and adopted. Clockwise and counter-clockwise rotating streamwise vortices are sampled and the probability density function of the vortex circulation Reynolds number and wall Nusselt number are calculated. From the results, the time-averaged secondary flow caused by instantaneous vortical motions has a great effect on the heat and momentum transport of the flow in the rectangular ducts. Hence, the wall Nusselt number is enhanced near the downwash flow region of the secondary flow. However, with increasing the aspect ratio, the effects of the hot-sweep flow of the clockwise and counter-clockwise rotating vortices become equally dominant near the wall normal bisector of the ducts. During time averaging process, these two counter-rotating vortices are canceled out each other diminishing a secondary flow but they still enhance the

  15. Development of Pre-set Counter-rotating Streamwise Vortices in Wavy Channel

    KAUST Repository

    Budiman, A.C.

    2015-10-23

    Development of counter-rotating streamwise vortices in a rectangular channel with one-sided wavy surface has been experimentally quantified using hot-wire anemometry. The wavy surface has fixed amplitude of 3.75 mm. The counter-rotating vortices are pre-set by means of a sawtooth pattern cut at the leading edge of the wavy surface. Variations of the central streamwise velocity Uc with a channel gap H = 35 mm and 50 mm (corresponding to a Reynolds number from 1600 to 4400) change the instability of the flow which can be distinguished from the velocity contours at a certain spanwise plane. The streamwise velocity contours and turbulence intensity for Reynolds number Re = 3100 and H = 35 mm show the disappearance of the mushroom-like vortices prior to turbulence near the second peak of the wavy surface, while for higher Re, this phenomenon occurs earlier. Under certain conditions, for example, for Re = 4400 and H = 50 mm, the splitting of the vortices can also be observed.

  16. Development of Pre-set Counter-rotating Streamwise Vortices in Wavy Channel

    KAUST Repository

    Budiman, A.C.; Mitsudharmadi, Hatsari; Bouremel, Y.; Winoto, S.H.; Low, H.T.

    2015-01-01

    Development of counter-rotating streamwise vortices in a rectangular channel with one-sided wavy surface has been experimentally quantified using hot-wire anemometry. The wavy surface has fixed amplitude of 3.75 mm. The counter-rotating vortices are pre-set by means of a sawtooth pattern cut at the leading edge of the wavy surface. Variations of the central streamwise velocity Uc with a channel gap H = 35 mm and 50 mm (corresponding to a Reynolds number from 1600 to 4400) change the instability of the flow which can be distinguished from the velocity contours at a certain spanwise plane. The streamwise velocity contours and turbulence intensity for Reynolds number Re = 3100 and H = 35 mm show the disappearance of the mushroom-like vortices prior to turbulence near the second peak of the wavy surface, while for higher Re, this phenomenon occurs earlier. Under certain conditions, for example, for Re = 4400 and H = 50 mm, the splitting of the vortices can also be observed.

  17. Face-Lift

    Science.gov (United States)

    ... or sun damage, you might also consider a skin-resurfacing procedure. A face-lift can be done in combination with some other cosmetic procedures, such as a brow lift or eyelid surgery. Why it's done As you get older, your facial skin changes — sagging and becoming loose. This can make ...

  18. Development of Streamwise Counter-Rotating Vortices in Flat Plate Boundary Layer Pre-set by Leading Edge Patterns

    KAUST Repository

    Hasheminejad, S.M.; Mitsudharmadi, Hatsari; Winoto, S.H.; Low, H.T.; Lua, K.B.

    2017-01-01

    Development of streamwise counter-rotating vortices induced by leading edge patterns with different pattern shape is investigated using hot-wire anemometry in the boundary layer of a flat plate. A triangular, sinusoidal and notched patterns

  19. FREIGHT CONTAINER LIFTING STANDARD

    Energy Technology Data Exchange (ETDEWEB)

    POWERS DJ; SCOTT MA; MACKEY TC

    2010-01-13

    This standard details the correct methods of lifting and handling Series 1 freight containers following ISO-3874 and ISO-1496. The changes within RPP-40736 will allow better reading comprehension, as well as correcting editorial errors.

  20. Wind tower service lift

    Science.gov (United States)

    Oliphant, David; Quilter, Jared; Andersen, Todd; Conroy, Thomas

    2011-09-13

    An apparatus used for maintaining a wind tower structure wherein the wind tower structure may have a plurality of legs and may be configured to support a wind turbine above the ground in a better position to interface with winds. The lift structure may be configured for carrying objects and have a guide system and drive system for mechanically communicating with a primary cable, rail or other first elongate member attached to the wind tower structure. The drive system and guide system may transmit forces that move the lift relative to the cable and thereby relative to the wind tower structure. A control interface may be included for controlling the amount and direction of the power into the guide system and drive system thereby causing the guide system and drive system to move the lift relative to said first elongate member such that said lift moves relative to said wind tower structure.

  1. Lattice Boltzmann simulation of the convective heat transfer from a stream-wise oscillating circular cylinder

    International Nuclear Information System (INIS)

    Bao Sheng; Chen Sheng; Liu Zhaohui; Zheng Chuguang

    2012-01-01

    Highlights: ► Heat transfer is enhanced by small and slow stream-wise oscillation. ► The average Nu decreases with increasing oscillation frequency. ► The RMS Nu increases with increasing frequency. ► The mean and RMS Nu reach a local maximum value in locked regime. ► Similar frequency effect is found for different Reynolds numbers. - Abstract: In this paper, we studied the convective heat transfer from a stream-wise oscillating circular cylinder. Two dimensional numerical simulations are conducted at Re = 100–200, A = 0.1–0.4 and F = f o /f s = 0.2–3.0 with the aid of the lattice Boltzmann method. In particular, detailed attentions are paid on the extensive numerical results elucidating the influence of oscillation frequency, oscillation amplitude and Reynolds number on the time-average and RMS value of the Nusselt number. Over the ranges of conditions considered herein, the heat transfer characteristics are observed to be influenced in an intricate manner by the value of the oscillation frequency (F), oscillation amplitude (A) and Reynolds number (Re). Firstly, the heat transfer is enhanced when the cylinder oscillates stream-wise with small amplitude and low frequency, while it will be reduced by large amplitude and high frequency. Secondly, the average Nusselt number (Nu (ave)) decreases against the increasing value of oscillation frequency, while the RMS value of the Nusselt number, Nu (RMS), displays an opposite trend. Third, we obtained a similar frequency effect on the heat transfer over the range of Reynolds numbers investigated in this paper. In addition, detailed analyses on phase portraits, energy spectrum are also made.

  2. Essential Development of Streamwise Vortical/Secondary Flows in All Ducts with Corners or Slope Discontinuities in Perimeter

    Science.gov (United States)

    Nagib, Hassan; Vidal, Alvaro; Vinuesa, Ricardo; Schlatter, Philipp

    2017-11-01

    Direct numerical simulations of fully-developed turbulent flow through various straight ducts with sharp or rounded corners of various radii were performed to study influence of corner geometry on secondary flows. Unexpectedly, increased rounding of corners in rectangular ducts does not lead to monotonic trend towards pipe case. Instead, secondary vortices relocate close to regions of wall-curvature change. This behavior is connected to inhomogeneous interaction between near-wall bursting events, which are further characterized in this work with definition of their local preferential direction, and vorticity fluxes. Although these motions are relatively weak compared to streamwise velocity their effect on turbulence statistics and shear-stress distribution is very important and has not been sufficiently documented or fully understood. Flow through spanwise-periodic channels, with sinusoidal function to define the geometry of wall, yw = +/- h + A cos(ωz) , was also studied as model flow that is parametrically changed using A and ω, while taking advantage of many resulting symmetries. Consequences on experimental facilities and comparisons between experiments and various numerical and theoretical models are discussed revealing the uniqueness of pipe flow.

  3. Regional changes in spine posture at lift onset with changes in lift distance and lift style

    NARCIS (Netherlands)

    Gill, K.P.; Bennet, S.J.; Savelsbergh, G.J.P.; van Dieen, J.H.

    2007-01-01

    STUDY DESIGN. Repeated measures experiment. OBJECTIVE. To determine the effect of changes in horizontal lift distance on the amount of flexion, at lift onset, in different spine regions when using different lift styles. SUMMARY OF BACKGROUND DATA. By approximating spine bending during lifting as a

  4. Drag reduction by streamwise traveling wave-like Lorenz Force in channel flow

    International Nuclear Information System (INIS)

    Mamori, Hiroya; Fukagata, Koji

    2011-01-01

    Skin-friction drag reduction effect of traveling wave-like wall-normal Lorenz force in a fully developed turbulent channel flow is investigated by means of direct numerical simulation. A sinusoidal profile of the wall-normal body force is assumed as the Lorenz force. While upstream traveling waves reduce the drag in the case of blowing/suction, standing waves reduce it in the case of present forcing. Visualization of vortical structure under the standing wave-like wall-normal Lorenz force reveals that the near-wall streamwise vortices, which increase the skin-friction drag, disappear and spanwise roller-like vortices are generated instead. Three component decomposition of the Reynolds shear stress indicates that the spanwise roller-like vortices contribute to the negative Reynolds shear stress in the region near the wall, similarly to the case of laminar flows. While the analogy between the wall-normal and streamwise forcings can be expected, the statistics are found to exhibit different behaviors due to the difference in the energy flow.

  5. Characterization of counter-rotating streamwise vortices in flat rectangular channel with one-sided wavy wall

    KAUST Repository

    Bouremel, Yann; Mitsudharmadi, Hatsari; Budiman, Alexander C.; Winoto, Sonny H.

    2016-01-01

    Particle Image Velocimetry (PIV) has been used to characterize the evolution of counter-rotating streamwise vortices in a rectangular channel with one sided wavy surface. The vortices were created by a uniform set of saw-tooth carved over the leading edge of a flat plate at the entrance of a flat rectangular channel with one-sided wavy wall. PIV measurements were taken over the spanwise and streamwise planes at different locations and at Reynolds number of 2500. Two other Reynolds numbers of 2885 and 3333 have also been considered for quantification purpose. Pairs of counter-rotating streamwise vortices have been shown experimentally to be centred along the spanwise direction at the saw-tooth valley where the vorticity ωz=0ωz=0. It has also been found that the vorticity ωzωz of the pairs of counter-rotating vortices decreases along the streamwise direction, and increases with the Reynolds number. Moreover, different quantifications of such counter-rotating vortices have been discussed such as their size, boundary layer, velocity profile and vorticity. The current study shows that the mixing due to the wall shear stress of counter-rotating streamwise vortices as well as their averaged viscous dissipation rate of kinetic energy decrease over flat and adverse pressure gradient surfaces while increasing over favourable pressure gradient surfaces. Finally, it was also demonstrated that the main direction of stretching is orientated at around 45° with the main flow direction.

  6. Characterization of counter-rotating streamwise vortices in flat rectangular channel with one-sided wavy wall

    KAUST Repository

    Bouremel, Yann

    2016-11-01

    Particle Image Velocimetry (PIV) has been used to characterize the evolution of counter-rotating streamwise vortices in a rectangular channel with one sided wavy surface. The vortices were created by a uniform set of saw-tooth carved over the leading edge of a flat plate at the entrance of a flat rectangular channel with one-sided wavy wall. PIV measurements were taken over the spanwise and streamwise planes at different locations and at Reynolds number of 2500. Two other Reynolds numbers of 2885 and 3333 have also been considered for quantification purpose. Pairs of counter-rotating streamwise vortices have been shown experimentally to be centred along the spanwise direction at the saw-tooth valley where the vorticity ωz=0ωz=0. It has also been found that the vorticity ωzωz of the pairs of counter-rotating vortices decreases along the streamwise direction, and increases with the Reynolds number. Moreover, different quantifications of such counter-rotating vortices have been discussed such as their size, boundary layer, velocity profile and vorticity. The current study shows that the mixing due to the wall shear stress of counter-rotating streamwise vortices as well as their averaged viscous dissipation rate of kinetic energy decrease over flat and adverse pressure gradient surfaces while increasing over favourable pressure gradient surfaces. Finally, it was also demonstrated that the main direction of stretching is orientated at around 45° with the main flow direction.

  7. A hypersonic lift mechanism with decoupled lift and drag surfaces

    Science.gov (United States)

    Xu, YiZhe; Xu, ZhiQi; Li, ShaoGuang; Li, Juan; Bai, ChenYuan; Wu, ZiNiu

    2013-05-01

    In the present study, we propose a novel lift mechanism for which the lifting surface produces only lift. This is achieved by mounting a two-dimensional shock-shock interaction generator below the lifting surface. The shock-shock interaction theory in conjunction with a three dimensional correction and checked with computational fluid dynamics (CFD) is used to analyze the lift and drag forces as function of the geometrical parameters and inflow Mach number. Through this study, though limited to only inviscid flow, we conclude that it is possible to obtain a high lift to drag ratio by suitably arranging the shock interaction generator.

  8. Waste Package Lifting Calculation

    International Nuclear Information System (INIS)

    H. Marr

    2000-01-01

    The objective of this calculation is to evaluate the structural response of the waste package during the horizontal and vertical lifting operations in order to support the waste package lifting feature design. The scope of this calculation includes the evaluation of the 21 PWR UCF (pressurized water reactor uncanistered fuel) waste package, naval waste package, 5 DHLW/DOE SNF (defense high-level waste/Department of Energy spent nuclear fuel)--short waste package, and 44 BWR (boiling water reactor) UCF waste package. Procedure AP-3.12Q, Revision 0, ICN 0, calculations, is used to develop and document this calculation

  9. Pressure distribution data from tests of 2.29 M (7.5 feet) span EET high-lift transport aircraft model in the Ames 12-foot pressure tunnel

    Science.gov (United States)

    Kjelgaard, S. O.; Morgan, H. L., Jr.

    1983-01-01

    A high-lift transport aircraft model equipped with full-span leading-edge slat and part-span double-slotted trailing-edge flap was tested in the Ames 12-ft pressure tunnel to determine the low-speed performance characteristics of a representative high-aspect-ratio supercritical wing. These tests were performed in support of the Energy Efficient Transport (EET) program which is one element of the Aircraft Energy Efficiency (ACEE) project. Static longitudinal forces and moments and chordwise pressure distributions at three spanwise stations were measured for cruise, climb, two take-off flap, and two landing flap wing configurations. The tabulated and plotted pressure distribution data is presented without analysis or discussion.

  10. Skin-friction drag reduction in turbulent channel flow based on streamwise shear control

    International Nuclear Information System (INIS)

    Kim, Jung Hoon; Lee, Jae Hwa

    2017-01-01

    Highlights: • We perform DNSs of fully developed turbulent channel flows to explore an active flow control concept using streamwise velocity shear control at the wall. • The structural spacing and wall amplitude parameters are systematically changed to achieve a high-efficient drag reduction rate for longitudinal control surface. • Significant drag reduction is observed with an increase in the two parameters with an accompanying reduction of the Reynolds stresses and vorticity fluctuations. • The generation and evolution of the turbulent vortices in the absence of velocity shear and how they contribute to DR have been examined. - Abstract: It is known that stretching and intensification of a hairpin vortex by mean shear play an important role to create a hairpin vortex packet, which generates the large Reynolds shear stress associated with skin-friction drag in wall-bounded turbulent flows. In order to suppress the mean shear at the wall for high efficient drag reduction (DR), in the present study, we explore an active flow control concept using streamwise shear control (SSC) at the wall. The longitudinal control surface is periodically spanwise-arranged with no-control surface while varying the structural spacing, and an amplitude parameter for imposing the strength of the actuating streamwise velocity at the wall is introduced to further enhance the skin-friction DR. Significant DR is observed with an increase in the two parameters with an accompanying reduction of the Reynolds stresses and vorticity fluctuations, although a further increase in the parameters amplifies the turbulence activity in the near-wall region. In order to study the direct relationship between turbulent vortical structures and DR under the SSC, temporal evolution with initial eddies extracted by conditional averages for Reynolds-stress-maximizing Q2 events are examined. It is shown that the generation of new vortices is dramatically inhibited with an increase in the parameters

  11. Knees Lifted High

    Centers for Disease Control (CDC) Podcasts

    The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Knees Lifted High gives children fun ideas for active outdoor play.

  12. JWST Lifting System

    Science.gov (United States)

    Tolleson, William

    2012-01-01

    A document describes designing, building, testing, and certifying a customized crane (Lifting Device LD) with a strong back (cradle) to facilitate the installation of long wall panels and short door panels for the GHe phase of the James Webb Space Telescope (JWST). The LD controls are variable-frequency drive controls designed to be adjustable for very slow and very-short-distance movements throughout the installation. The LD has a lift beam with an electric actuator attached at the end. The actuator attaches to a rectangular strong back (cradle) for lifting the long wall panels and short door panels from a lower angle into the vertical position inside the chamber, and then rotating around the chamber for installation onto the existing ceiling and floor. The LD rotates 360 (in very small increments) in both clockwise and counterclockwise directions. Eight lifting pads are on the top ring with 2-in. (.5-cm) eye holes spaced evenly around the ring to allow for the device to be suspended by three crane hoists from the top of the chamber. The LD is operated by remote controls that allow for a single, slow mode for booming the load in and out, with slow and very slow modes for rotating the load.

  13. LIFT11 linnas

    Index Scriptorium Estoniae

    2010-01-01

    Tallinn 2011 programmi kuuluva installatsioonide festivali "Lift11" avalikule ideekonkursile esitati 129 tööd, välja valiti 17. Tutvustatakse Maarja Kase ja Ralf Lõokese tööd "L", Tomomi Hayashi tööd "Merele!", Toomas Paaveri, Teele Pehki ja Triin Talki tööd "Kalarand"

  14. Lift11 / Ingrid Ruudi

    Index Scriptorium Estoniae

    Ruudi, Ingrid, 1978-

    2010-01-01

    23. augustist 11. oktoobrini 2010 toimuvast konkursist, mille eesmärk on leida kultuuripealinna üritusena toimuva linnainstallatsioonide festivali "Lift11" tarvis installatsioonide ideekavandeid. Festivali kuraatorid on kunstiteadlased Maarin Mürk ja Ingrid Ruudi ning arhitektid Margit Aule ja Margit Argus

  15. Heterotic weight lifting

    Energy Technology Data Exchange (ETDEWEB)

    Gato-Rivera, B. [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); Schellekens, A.N., E-mail: t58@nikhef.n [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); IMAPP, Radboud Universiteit, Nijmegen (Netherlands)

    2010-03-21

    We describe a method for constructing genuinely asymmetric (2,0) heterotic strings out of N=2 minimal models in the fermionic sector, whereas the bosonic sector is only partly build out of N=2 minimal models. This is achieved by replacing one minimal model plus the superfluous E{sub 8} factor by a non-supersymmetric CFT with identical modular properties. This CFT generically lifts the weights in the bosonic sector, giving rise to a spectrum with fewer massless states. We identify more than 30 such lifts, and we expect many more to exist. This yields more than 450 different combinations. Remarkably, despite the lifting of all Ramond states, it is still possible to get chiral spectra. Even more surprisingly, these chiral spectra include examples with a certain number of chiral families of SO(10), SU(5) or other subgroups, including just SU(3)xSU(2)xU(1). The number of families and mirror families is typically smaller than in standard Gepner models. Furthermore, in a large number of different cases, spectra with three chiral families can be obtained. Based on a first scan of about 10% of the lifted Gepner models we can construct, we have collected more than 10,000 distinct spectra with three families, including examples without mirror fermions. We present an example where the GUT group is completely broken to the standard model, but the resulting and inevitable fractionally charged particles are confined by an additional gauge group factor.

  16. Heterotic weight lifting

    International Nuclear Information System (INIS)

    Gato-Rivera, B.; Schellekens, A.N.

    2010-01-01

    We describe a method for constructing genuinely asymmetric (2,0) heterotic strings out of N=2 minimal models in the fermionic sector, whereas the bosonic sector is only partly build out of N=2 minimal models. This is achieved by replacing one minimal model plus the superfluous E 8 factor by a non-supersymmetric CFT with identical modular properties. This CFT generically lifts the weights in the bosonic sector, giving rise to a spectrum with fewer massless states. We identify more than 30 such lifts, and we expect many more to exist. This yields more than 450 different combinations. Remarkably, despite the lifting of all Ramond states, it is still possible to get chiral spectra. Even more surprisingly, these chiral spectra include examples with a certain number of chiral families of SO(10), SU(5) or other subgroups, including just SU(3)xSU(2)xU(1). The number of families and mirror families is typically smaller than in standard Gepner models. Furthermore, in a large number of different cases, spectra with three chiral families can be obtained. Based on a first scan of about 10% of the lifted Gepner models we can construct, we have collected more than 10,000 distinct spectra with three families, including examples without mirror fermions. We present an example where the GUT group is completely broken to the standard model, but the resulting and inevitable fractionally charged particles are confined by an additional gauge group factor.

  17. Vertical vector face lift.

    Science.gov (United States)

    Somoano, Brian; Chan, Joanna; Morganroth, Greg

    2011-01-01

    Facial rejuvenation using local anesthesia has evolved in the past decade as a safer option for patients seeking fewer complications and minimal downtime. Mini- and short-scar face lifts using more conservative incision lengths and extent of undermining can be effective in the younger patient with lower face laxity and minimal loose, elastotic neck skin. By incorporating both an anterior and posterior approach and using an incision length between the mini and more traditional face lift, the Vertical Vector Face Lift can achieve longer-lasting and natural results with lesser cost and risk. Submentoplasty and liposuction of the neck and jawline, fundamental components of the vertical vector face lift, act synergistically with superficial musculoaponeurotic system plication to reestablish a more youthful, sculpted cervicomental angle, even in patients with prominent jowls. Dramatic results can be achieved in the right patient by combining with other procedures such as injectable fillers, chin implants, laser resurfacing, or upper and lower blepharoplasties. © 2011 Wiley Periodicals, Inc.

  18. Lifting as You Climb

    Science.gov (United States)

    Sullivan, Debra R.

    2009-01-01

    This article addresses leadership themes and answers leadership questions presented to "Exchange" by the Panel members who attended the "Exchange" Panel of 300 Reception in Dallas, Texas, last November. There is an old proverb that encourages people to lift as they climb: "While you climb a mountain, you must not forget others along the way." With…

  19. Wall-attached structures of streamwise velocity fluctuations in turbulent boundary layer

    Science.gov (United States)

    Hwang, Jinyul; Sung, Hyung Jin

    2017-11-01

    The wall-attached structures of streamwise velocity fluctuations (u) are explored using direct numerical simulation data of turbulent boundary layer at Reτ = 1000 . We identify the structures of u, which are extended close to the wall. Their height (ly) ranges from the near-wall region to the edge of turbulent boundary layer. They are geometrically self-similar in a sense that the length and width of the structures are proportional to the distance from the wall. The population density of the attached structures shows that the tall attached structures (290 wall. The wall-attached structures of u identified in the present work are a proper candidate for Townsend's attached eddy hypothesis and these structures exist in the low Reynolds number turbulent boundary layer. This work was supported by the Creative Research Initiatives (No. 2017-013369) program of the National Research Foundation of Korea (MSIP) and supported by the Supercomputing Center (KISTI).

  20. Helicopter Toy and Lift Estimation

    Science.gov (United States)

    Shakerin, Said

    2013-01-01

    A $1 plastic helicopter toy (called a Wacky Whirler) can be used to demonstrate lift. Students can make basic measurements of the toy, use reasonable assumptions and, with the lift formula, estimate the lift, and verify that it is sufficient to overcome the toy's weight. (Contains 1 figure.)

  1. How Do Wings Generate Lift?

    Indian Academy of Sciences (India)

    ideas to get expressions for lift and moment that are remarkably accurate. The pressure ... ating a lift force, leads to a nose-up or nose-down moment also. .... venient to use for a fluid since we would like to deal with a flow .... energy to get lift?

  2. Fuel Cell Powered Lift Truck

    Energy Technology Data Exchange (ETDEWEB)

    Moulden, Steve [Sysco Food Service, Houston, TX (United States)

    2015-08-20

    This project, entitled “Recovery Act: Fuel Cell-Powered Lift Truck Sysco (Houston) Fleet Deployment”, was in response to DOE funding opportunity announcement DE-PS36-08GO98009, Topic 7B, which promotes the deployment of fuel cell powered material handling equipment in large, multi-shift distribution centers. This project promoted large-volume commercialdeployments and helped to create a market pull for material handling equipment (MHE) powered fuel cell systems. Specific outcomes and benefits involved the proliferation of fuel cell systems in 5-to 20-kW lift trucks at a high-profile, real-world site that demonstrated the benefits of fuel cell technology and served as a focal point for other nascent customers. The project allowed for the creation of expertise in providing service and support for MHE fuel cell powered systems, growth of existing product manufacturing expertise, and promoted existing fuel cell system and component companies. The project also stimulated other MHE fleet conversions helping to speed the adoption of fuel cell systems and hydrogen fueling technology. This document also contains the lessons learned during the project in order to communicate the successes and difficulties experienced, which could potentially assist others planning similar projects.

  3. Optimization of lift gas allocation in a gas lifted oil field as non-linear optimization problem

    Directory of Open Access Journals (Sweden)

    Roshan Sharma

    2012-01-01

    Full Text Available Proper allocation and distribution of lift gas is necessary for maximizing total oil production from a field with gas lifted oil wells. When the supply of the lift gas is limited, the total available gas should be optimally distributed among the oil wells of the field such that the total production of oil from the field is maximized. This paper describes a non-linear optimization problem with constraints associated with the optimal distribution of the lift gas. A non-linear objective function is developed using a simple dynamic model of the oil field where the decision variables represent the lift gas flow rate set points of each oil well of the field. The lift gas optimization problem is solved using the emph'fmincon' solver found in MATLAB. As an alternative and for verification, hill climbing method is utilized for solving the optimization problem. Using both of these methods, it has been shown that after optimization, the total oil production is increased by about 4. For multiple oil wells sharing lift gas from a common source, a cascade control strategy along with a nonlinear steady state optimizer behaves as a self-optimizing control structure when the total supply of lift gas is assumed to be the only input disturbance present in the process. Simulation results show that repeated optimization performed after the first time optimization under the presence of the input disturbance has no effect in the total oil production.

  4. SPIV investigations of correlation between streamwise vorticity and velocity in the wake of a vortex generator in a boundary layer

    DEFF Research Database (Denmark)

    Velte, Clara Marika; Okulov, Valery; Hansen, Martin Otto Laver

    2013-01-01

    The current work describes the experimental parametric study of streamwise vortices generated in a boundary layer by a rectangular vane (commonly named vortex generator) mounted perpendicularly to the wall and at an angle to the oncoming flow. Stereoscopic Particle Image Velocimetry measurements ...

  5. Two-dimensional unsteady lift problems in supersonic flight

    Science.gov (United States)

    Heaslet, Max A; Lomax, Harvard

    1949-01-01

    The variation of pressure distribution is calculated for a two-dimensional supersonic airfoil either experiencing a sudden angle-of-attack change or entering a sharp-edge gust. From these pressure distributions the indicial lift functions applicable to unsteady lift problems are determined for two cases. Results are presented which permit the determination of maximum increment in lift coefficient attained by an unrestrained airfoil during its flight through a gust. As an application of these results, the minimum altitude for safe flight through a specific gust is calculated for a particular supersonic wing of given strength and wing loading.

  6. Can a new behaviorally oriented training process to improve lifting technique prevent occupationally related back injuries due to lifting?

    Science.gov (United States)

    Lavender, Steven A; Lorenz, Eric P; Andersson, Gunnar B J

    2007-02-15

    A prospective randomized control trial. To determine the degree to which a new behavior-based lift training program (LiftTrainer; Ascension Technology, Burlington, VT) could reduce the incidence of low back disorder in distribution center jobs that require repetitive lifting. Most studies show programs aimed at training lifting techniques to be ineffective in preventing low back disorders, which may be due to their conceptual rather than behavioral learning approach. A total of 2144 employees in 19 distribution centers were randomized into either the LiftTrainer program or a video control group. In the LiftTrainer program, participants were individually trained in up to 5, 30-minute sessions while instrumented with motion capture sensors to quantify the L5/S1 moments. Twelve months following the initial training, injury data were obtained from company records. Survival analyses (Kaplan-Meier) indicated that there was no difference in injury rates between the 2 training groups. Likewise, there was no difference in the turnover rates. However, those with a low (<30 Nm) average twisting moment at the end of the first session experienced a significantly (P < 0.005) lower rate of low back disorder than controls. While overall the LiftTrainer program was not effective, those with twisting moments below 30 Nm reported fewer injuries, suggesting a shift in focus for "safe" lifting programs.

  7. Remote determination of the velocity index and mean streamwise velocity profiles

    Science.gov (United States)

    Johnson, E. D.; Cowen, E. A.

    2017-09-01

    When determining volumetric discharge from surface measurements of currents in a river or open channel, the velocity index is typically used to convert surface velocities to depth-averaged velocities. The velocity index is given by, k=Ub/Usurf, where Ub is the depth-averaged velocity and Usurf is the local surface velocity. The USGS (United States Geological Survey) standard value for this coefficient, k = 0.85, was determined from a series of laboratory experiments and has been widely used in the field and in laboratory measurements of volumetric discharge despite evidence that the velocity index is site-specific. Numerous studies have documented that the velocity index varies with Reynolds number, flow depth, and relative bed roughness and with the presence of secondary flows. A remote method of determining depth-averaged velocity and hence the velocity index is developed here. The technique leverages the findings of Johnson and Cowen (2017) and permits remote determination of the velocity power-law exponent thereby, enabling remote prediction of the vertical structure of the mean streamwise velocity, the depth-averaged velocity, and the velocity index.

  8. Streamwise counter-rotating vortices generated by triangular leading edge pattern in flat plate boundary layer

    KAUST Repository

    Hasheminejad, S. M.

    2016-01-05

    A series of flow visualizations were conducted to qualitatively study the development of streamwise counter-rotating vortices over a flat plate induced by triangular patterns at the leading edge of a flat plate. The experiments were carried out for a Reynolds number based on the pattern wavelength (λ) of 3080. The results depict the onset, development and breakdown of the vortical structures within the flat plate boundary layer. Moreover, the effect of one spanwise array of holes with diameter of 0.2λ (=3 mm) was examined. This investigation was done on two different flat plates with holes placed at the location x/λ = 2 downstream of the troughs and peaks. The presence of holes after troughs does not show any significant effect on the vortical structures. However, the plate with holes after peaks noticeably delays the vortex breakdown. In this case, the “mushroom-like” vortices move away from the wall and propagate downstream with stable vortical structures. The vortex growth is halted further downstream but start to tilt aside.

  9. Attached flow structure and streamwise energy spectra in a turbulent boundary layer

    Science.gov (United States)

    Srinath, S.; Vassilicos, J. C.; Cuvier, C.; Laval, J.-P.; Stanislas, M.; Foucaut, J.-M.

    2018-05-01

    On the basis of (i) particle image velocimetry data of a turbulent boundary layer with large field of view and good spatial resolution and (ii) a mathematical relation between the energy spectrum and specifically modeled flow structures, we show that the scalings of the streamwise energy spectrum E11(kx) in a wave-number range directly affected by the wall are determined by wall-attached eddies but are not given by the Townsend-Perry attached eddy model's prediction of these spectra, at least at the Reynolds numbers Reτ considered here which are between 103 and 104. Instead, we find E11(kx) ˜kx-1 -p where p varies smoothly with distance to the wall from negative values in the buffer layer to positive values in the inertial layer. The exponent p characterizes the turbulence levels inside wall-attached streaky structures conditional on the length of these structures. A particular consequence is that the skin friction velocity is not sufficient to scale E11(kx) for wave numbers directly affected by the wall.

  10. Lift application development cookbook

    CERN Document Server

    Garcia, Gilberto T

    2013-01-01

    Lift Application Development Cookbook contains practical recipes on everything you will need to create secure web applications using this amazing framework.The book first teaches you basic topics such as starting a new application and gradually moves on to teach you advanced topics to achieve a certain task. Then, it explains every step in detail so that you can build your knowledge about how things work.This book is for developers who have at least some basic knowledge about Scala and who are looking for a functional, secure, and modern web framework. Prior experience with HTML and JavaScript

  11. Knees Lifted High

    Centers for Disease Control (CDC) Podcasts

    2008-08-04

    The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Knees Lifted High gives children fun ideas for active outdoor play.  Created: 8/4/2008 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 8/5/2008.

  12. Three-dimensional instability analysis of boundary layers perturbed by streamwise vortices

    Science.gov (United States)

    Martín, Juan A.; Paredes, Pedro

    2017-12-01

    A parametric study is presented for the incompressible, zero-pressure-gradient flat-plate boundary layer perturbed by streamwise vortices. The vortices are placed near the leading edge and model the vortices induced by miniature vortex generators (MVGs), which consist in a spanwise-periodic array of small winglet pairs. The introduction of MVGs has been experimentally proved to be a successful passive flow control strategy for delaying laminar-turbulent transition caused by Tollmien-Schlichting (TS) waves. The counter-rotating vortex pairs induce non-modal, transient growth that leads to a streaky boundary layer flow. The initial intensity of the vortices and their wall-normal distances to the plate wall are varied with the aim of finding the most effective location for streak generation and the effect on the instability characteristics of the perturbed flow. The study includes the solution of the three-dimensional, stationary, streaky boundary layer flows by using the boundary region equations, and the three-dimensional instability analysis of the resulting basic flows by using the plane-marching parabolized stability equations. Depending on the initial circulation and positioning of the vortices, planar TS waves are stabilized by the presence of the streaks, resulting in a reduction in the region of instability and shrink of the neutral stability curve. For a fixed maximum streak amplitude below the threshold for secondary instability (SI), the most effective wall-normal distance for the formation of the streaks is found to also offer the most stabilization of TS waves. By setting a maximum streak amplitude above the threshold for SI, sinuous shear layer modes become unstable, as well as another instability mode that is amplified in a narrow region near the vortex inlet position.

  13. A new technique for dynamic load distribution when two manipulators mutually lift a rigid object. Part 2, Derivation of entire system model and control architecture

    Energy Technology Data Exchange (ETDEWEB)

    Unseren, M.A.

    1994-04-01

    A rigid body model for the entire system which accounts for the load distribution scheme proposed in Part 1 as well as for the dynamics of the manipulators and the kinematic constraints is derived in the joint space. A technique is presented for expressing the object dynamics in terms of the joint variables of both manipulators which leads to a positive definite and symmetric inertia matrix. The model is then transformed to obtain reduced order equations of motion and a separate set of equations which govern the behavior of the internal contact forces. The control architecture is applied to the model which results in the explicit decoupling of the position and internal contact force-controlled degrees of freedom (DOF).

  14. Lifting devices in nuclear facilities

    International Nuclear Information System (INIS)

    The rule is valid for lifts, cranes, winches, rail travel trolleys, load lifting devices and fuel element changing devices for light-water reactors, insofar as these are used in plants to produce or to fission nuclear fuels or to process irradiated nuclear fuels or in the storage or other use of nuclear fuels. (LH) [de

  15. Project LIFT: Year 1 Report

    Science.gov (United States)

    Norton, Michael; Piccinino, Kelly

    2014-01-01

    Research for Action (RFA) is currently in the second year of a five-year external evaluation of the Project Leadership and Investment for Transformation (LIFT) Initiative in the Charlotte-Mecklenburg School District (CMS). Project LIFT is a public-private partnership between CMS and the local philanthropic and business communities in Charlotte,…

  16. A review of a method for dynamic load distribution, dynamic modeling, and explicit internal force control when two serial link manipulators mutually lift and transport a rigid body object

    International Nuclear Information System (INIS)

    Unseren, M.A.

    1997-09-01

    The report reviews a method for modeling and controlling two serial link manipulators which mutually lift and transport a rigid body object in a three dimensional workspace. A new vector variable is introduced which parameterizes the internal contact force controlled degrees of freedom. A technique for dynamically distributing the payload between the manipulators is suggested which yields a family of solutions for the contact forces and torques the manipulators impart to the object. A set of rigid body kinematic constraints which restricts the values of the joint velocities of both manipulators is derived. A rigid body dynamical model for the closed chain system is first developed in the joint space. The model is obtained by generalizing the previous methods for deriving the model. The joint velocity and acceleration variables in the model are expressed in terms of independent pseudovariables. The pseudospace model is transformed to obtain reduced order equations of motion and a separate set of equations governing the internal components of the contact forces and torques. A theoretic control architecture is suggested which explicitly decouples the two sets of equations comprising the model. The controller enables the designer to develop independent, non-interacting control laws for the position control and internal force control of the system

  17. A review of a method for dynamic load distribution, dynamic modeling, and explicit internal force control when two serial link manipulators mutually lift and transport a rigid body object

    Energy Technology Data Exchange (ETDEWEB)

    Unseren, M.A.

    1997-09-01

    The report reviews a method for modeling and controlling two serial link manipulators which mutually lift and transport a rigid body object in a three dimensional workspace. A new vector variable is introduced which parameterizes the internal contact force controlled degrees of freedom. A technique for dynamically distributing the payload between the manipulators is suggested which yields a family of solutions for the contact forces and torques the manipulators impart to the object. A set of rigid body kinematic constraints which restricts the values of the joint velocities of both manipulators is derived. A rigid body dynamical model for the closed chain system is first developed in the joint space. The model is obtained by generalizing the previous methods for deriving the model. The joint velocity and acceleration variables in the model are expressed in terms of independent pseudovariables. The pseudospace model is transformed to obtain reduced order equations of motion and a separate set of equations governing the internal components of the contact forces and torques. A theoretic control architecture is suggested which explicitly decouples the two sets of equations comprising the model. The controller enables the designer to develop independent, non-interacting control laws for the position control and internal force control of the system.

  18. Wavelets and the Lifting Scheme

    DEFF Research Database (Denmark)

    la Cour-Harbo, Anders; Jensen, Arne

    The objective of this article is to give a concise introduction to the discrete wavelet transform (DWT) based on a technique called lifting. The lifting technique allows one to give an elementary, but rigorous, definition of the DWT, with modest requirements on the reader. A basic knowledge...... of linear algebra and signal processing will suffice. The lifting based definition is equivalent to the usual filer bank based definition of the DWT. The article does not discuss applications in any detail. The reader is referred to other articles in this collection....

  19. Wavelets and the lifting scheme

    DEFF Research Database (Denmark)

    la Cour-Harbo, Anders; Jensen, Arne

    2012-01-01

    The objective of this article is to give a concise introduction to the discrete wavelet transform (DWT) based on a technique called lifting. The lifting technique allows one to give an elementary, but rigorous, definition of the DWT, with modest requirements on the reader. A basic knowledge...... of linear algebra and signal processing will suffice. The lifting based definition is equivalent to the usual filer bank based definition of the DWT. The article does not discuss applications in any detail. The reader is referred to other articles in this collection....

  20. Wavelets and the lifting scheme

    DEFF Research Database (Denmark)

    la Cour-Harbo, Anders; Jensen, Arne

    2009-01-01

    The objective of this article is to give a concise introduction to the discrete wavelet transform (DWT) based on a technique called lifting. The lifting technique allows one to give an elementary, but rigorous, definition of the DWT, with modest requirements on the reader. A basic knowledge...... of linear algebra and signal processing will suffice. The lifting based definition is equivalent to the usual filer bank based definition of the DWT. The article does not discuss applications in any detail. The reader is referred to other articles in this collection....

  1. Lifting strength in two-person teamwork.

    Science.gov (United States)

    Lee, Tzu-Hsien

    2016-01-01

    This study examined the effects of lifting range, hand-to-toe distance, and lifting direction on single-person lifting strengths and two-person teamwork lifting strengths. Six healthy males and seven healthy females participated in this study. Two-person teamwork lifting strengths were examined in both strength-matched and strength-unmatched groups. Our results showed that lifting strength significantly decreased with increasing lifting range or hand-to-toe distance. However, lifting strengths were not affected by lifting direction. Teamwork lifting strength did not conform to the law of additivity for both strength-matched and strength-unmatched groups. In general, teamwork lifting strength was dictated by the weaker of the two members, implying that weaker members might be exposed to a higher potential danger in teamwork exertions. To avoid such overexertion in teamwork, members with significantly different strength ability should not be assigned to the same team.

  2. Nordic noir and lifted localities

    DEFF Research Database (Denmark)

    Hansen, Kim Toft

    What I do here is to draw attention to a particular visual quality of recent Nordic noir and to relate the visuality of TV-drama to what I – with a term borrowed from Roland Robertson – dub lifted localites.......What I do here is to draw attention to a particular visual quality of recent Nordic noir and to relate the visuality of TV-drama to what I – with a term borrowed from Roland Robertson – dub lifted localites....

  3. Null lifts and projective dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Cariglia, Marco, E-mail: marco@iceb.ufop.br

    2015-11-15

    We describe natural Hamiltonian systems using projective geometry. The null lift procedure endows the tangent bundle with a projective structure where the null Hamiltonian is identified with a projective conic and induces a Weyl geometry. Projective transformations generate a set of known and new dualities between Hamiltonian systems, as for example the phenomenon of coupling-constant metamorphosis. We conclude outlining how this construction can be extended to the quantum case for Eisenhart–Duval lifts.

  4. Spatial averaging of streamwise and spanwise velocity measurements in wall-bounded turbulence using ∨- and ×-probes

    International Nuclear Information System (INIS)

    Philip, Jimmy; Baidya, Rio; Hutchins, Nicholas; Monty, Jason P; Marusic, Ivan

    2013-01-01

    The effect of finite dimensions of ∨- and ×-probes is investigated for the measurement of mean and variances of streamwise and spanwise velocities in wall-turbulence. The probes are numerically simulated using a Direct Numerical Simulation database of channel flow at a friction Reynolds number (Re τ ) of 934 by varying the probe parameters, namely, the wire-lengths (l), the angle between the wires (θ) and the spacing between the wires (Δs). A single inclined wire is first studied to isolate the effect of l and θ. Analytical expressions for the variances of the streamwise and spanwise velocities are derived by applying a linear-box-type filter to the unfiltered velocity field for both ∨- and ×-probes (at θ = 45°, and arbitrary l and Δs). A similar expression for the streamwise variance in the case of a single inclined wire (for arbitrary l and θ) is also derived. These analytical expressions, supplemented with a model for the correlation over the wire-length, compare favourably with the numerical simulation results, and more importantly explain various trends that are observed in the variances with varying parameters. Close to the wall (where the errors are generally higher) the errors in spanwise variances of the ×-probes are much lower than the ∨-probes, owing to an ‘error-cancelling’ mechanism present in ×-probes due to the effect of l and Δs, as well as due to the procedure of recovering the velocities from two wires. The errors in the streamwise variances are comparable for both ∨- and ×-probes. On the other hand, mean velocities are measured with almost no error by the ∨-probe, whereas the ×-probe induces finite errors in mean velocities due to the fact that the two wires experience different mean velocities in ×-probes unlike ∨-probes. These results are explained using the corresponding analytical results, which also show that under the effect of a linear filter, measured variances depend only on the fluctuating velocities

  5. Lift-and-fill face lift: integrating the fat compartments.

    Science.gov (United States)

    Rohrich, Rod J; Ghavami, Ashkan; Constantine, Fadi C; Unger, Jacob; Mojallal, Ali

    2014-06-01

    Recent discovery of the numerous fat compartments of the face has improved our ability to more precisely restore facial volume while rejuvenating it through differential superficial musculoaponeurotic system treatment. Incorporation of selective fat compartment volume restoration along with superficial musculoaponeurotic system manipulation allows for improved control in recontouring while addressing one of the key problems in facial aging, namely, volume deflation. This theory was evaluated by assessing the contour changes from simultaneous face "lifting" and "filling" through fat compartment-guided facial fat transfer. A review of 100 face-lift patients was performed. All patients had an individualized component face lift with fat grafting to the nasolabial fold, deep malar, and high/lateral malar fat compartment locations. Photographic analysis using a computer program was conducted on oblique facial views preoperatively and postoperatively, to obtain the most projected malar contour point. Two independent observers visually evaluated the malar prominence and nasolabial fold improvements based on standardized photographs. Nasolabial fold improved by at least one grade in 81 percent and by over one grade in 11 percent. Malar prominence average projection increase was 13.47 percent and the average amount of lift was 12.24 percent. The malar prominence score improved by at least one grade in 62 percent of the patients postoperatively, and 9 percent had a greater than one grade improvement. Twenty-eight percent of the patients had a convex malar prominence postoperatively compared with 6 percent preoperatively. Malar prominence improved by at least one grade in 63 percent and by over one grade in 10 percent. The lift-and-fill face lift merges two key concepts in facial rejuvenation: (1) effective tissue manipulation by means of lifting and tightening in differential vectors according to original facial asymmetry and shape; and (2) selective fat compartment filling

  6. Estimation of unsteady lift on a pitching airfoil from wake velocity surveys

    Science.gov (United States)

    Zaman, K. B. M. Q.; Panda, J.; Rumsey, C. L.

    1993-01-01

    The results of a joint experimental and computational study on the flowfield over a periodically pitched NACA0012 airfoil, and the resultant lift variation, are reported in this paper. The lift variation over a cycle of oscillation, and hence the lift hysteresis loop, is estimated from the velocity distribution in the wake measured or computed for successive phases of the cycle. Experimentally, the estimated lift hysteresis loops are compared with available data from the literature as well as with limited force balance measurements. Computationally, the estimated lift variations are compared with the corresponding variation obtained from the surface pressure distribution. Four analytical formulations for the lift estimation from wake surveys are considered and relative successes of the four are discussed.

  7. Filtered Rayleigh scattering mixing measurements of merging and non-merging streamwise vortex interactions in supersonic flow

    Science.gov (United States)

    Ground, Cody R.; Gopal, Vijay; Maddalena, Luca

    2018-04-01

    By introducing large-scale streamwise vortices into a supersonic flow it is possible to enhance the rate of mixing between two fluid streams. However, increased vorticity content alone does not explicitly serve as a predictor of mixing enhancement. Additional factors, particularly the mutual interactions occurring between neighboring vortical structures, affect the underlying fundamental physics that influence the rate at which the fluids mix. As part of a larger systematic study on supersonic streamwise vortex interactions, this work experimentally quantifies the average rate of mixing of helium and air in the presence of two separate modes of vortex interaction, the merging and non-merging of a pair of co-rotating vortices. In these experiments vortex-generating expansion ramps are placed on a strut injector. The freestream Mach number is set at 2.5 and helium is injected as a passive scalar. Average injectant mole fractions at selected flow planes downstream of the injector are measured utilizing the filtered Rayleigh scattering technique. The filtered Rayleigh scattering measurements reveal that, in the domain surveyed, the merging vortex interaction strongly displaces the plume from its initial horizontal orientation while the non-merging vortex interaction more rapidly mixes the helium and air. The results of the current experiments are consistent with associated knowledge derived from previous analyses of the two studied configurations which have included the detailed experimental characterization of entrainment, turbulent kinetic energy, and vorticity of both modes of vortex interaction.

  8. Lift production through asymmetric flapping

    Science.gov (United States)

    Jalikop, Shreyas; Sreenivas, K. R.

    2009-11-01

    At present, there is a strong interest in developing Micro Air Vehicles (MAV) for applications like disaster management and aerial surveys. At these small length scales, the flight of insects and small birds suggests that unsteady aerodynamics of flapping wings can offer many advantages over fixed wing flight, such as hovering-flight, high maneuverability and high lift at large angles of attack. Various lift generating mechanims such as delayed stall, wake capture and wing rotation contribute towards our understanding of insect flight. We address the effect of asymmetric flapping of wings on lift production. By visualising the flow around a pair of rectangular wings flapping in a water tank and numerically computing the flow using a discrete vortex method, we demonstrate that net lift can be produced by introducing an asymmetry in the upstroke-to-downstroke velocity profile of the flapping wings. The competition between generation of upstroke and downstroke tip vortices appears to hold the key to understanding this lift generation mechanism.

  9. Normalized lift: an energy interpretation of the lift coefficient simplifies comparisons of the lifting ability of rotating and flapping surfaces.

    Directory of Open Access Journals (Sweden)

    Phillip Burgers

    Full Text Available For a century, researchers have used the standard lift coefficient C(L to evaluate the lift, L, generated by fixed wings over an area S against dynamic pressure, ½ρv(2, where v is the effective velocity of the wing. Because the lift coefficient was developed initially for fixed wings in steady flow, its application to other lifting systems requires either simplifying assumptions or complex adjustments as is the case for flapping wings and rotating cylinders.This paper interprets the standard lift coefficient of a fixed wing slightly differently, as the work exerted by the wing on the surrounding flow field (L/ρ·S, compared against the total kinetic energy required for generating said lift, ½v(2. This reinterpreted coefficient, the normalized lift, is derived from the work-energy theorem and compares the lifting capabilities of dissimilar lift systems on a similar energy footing. The normalized lift is the same as the standard lift coefficient for fixed wings, but differs for wings with more complex motions; it also accounts for such complex motions explicitly and without complex modifications or adjustments. We compare the normalized lift with the previously-reported values of lift coefficient for a rotating cylinder in Magnus effect, a bat during hovering and forward flight, and a hovering dipteran.The maximum standard lift coefficient for a fixed wing without flaps in steady flow is around 1.5, yet for a rotating cylinder it may exceed 9.0, a value that implies that a rotating cylinder generates nearly 6 times the maximum lift of a wing. The maximum normalized lift for a rotating cylinder is 1.5. We suggest that the normalized lift can be used to evaluate propellers, rotors, flapping wings of animals and micro air vehicles, and underwater thrust-generating fins in the same way the lift coefficient is currently used to evaluate fixed wings.

  10. Normalized Lift: An Energy Interpretation of the Lift Coefficient Simplifies Comparisons of the Lifting Ability of Rotating and Flapping Surfaces

    Science.gov (United States)

    Burgers, Phillip; Alexander, David E.

    2012-01-01

    For a century, researchers have used the standard lift coefficient CL to evaluate the lift, L, generated by fixed wings over an area S against dynamic pressure, ½ρv 2, where v is the effective velocity of the wing. Because the lift coefficient was developed initially for fixed wings in steady flow, its application to other lifting systems requires either simplifying assumptions or complex adjustments as is the case for flapping wings and rotating cylinders. This paper interprets the standard lift coefficient of a fixed wing slightly differently, as the work exerted by the wing on the surrounding flow field (L/ρ·S), compared against the total kinetic energy required for generating said lift, ½v2. This reinterpreted coefficient, the normalized lift, is derived from the work-energy theorem and compares the lifting capabilities of dissimilar lift systems on a similar energy footing. The normalized lift is the same as the standard lift coefficient for fixed wings, but differs for wings with more complex motions; it also accounts for such complex motions explicitly and without complex modifications or adjustments. We compare the normalized lift with the previously-reported values of lift coefficient for a rotating cylinder in Magnus effect, a bat during hovering and forward flight, and a hovering dipteran. The maximum standard lift coefficient for a fixed wing without flaps in steady flow is around 1.5, yet for a rotating cylinder it may exceed 9.0, a value that implies that a rotating cylinder generates nearly 6 times the maximum lift of a wing. The maximum normalized lift for a rotating cylinder is 1.5. We suggest that the normalized lift can be used to evaluate propellers, rotors, flapping wings of animals and micro air vehicles, and underwater thrust-generating fins in the same way the lift coefficient is currently used to evaluate fixed wings. PMID:22629326

  11. Normalized lift: an energy interpretation of the lift coefficient simplifies comparisons of the lifting ability of rotating and flapping surfaces.

    Science.gov (United States)

    Burgers, Phillip; Alexander, David E

    2012-01-01

    For a century, researchers have used the standard lift coefficient C(L) to evaluate the lift, L, generated by fixed wings over an area S against dynamic pressure, ½ρv(2), where v is the effective velocity of the wing. Because the lift coefficient was developed initially for fixed wings in steady flow, its application to other lifting systems requires either simplifying assumptions or complex adjustments as is the case for flapping wings and rotating cylinders.This paper interprets the standard lift coefficient of a fixed wing slightly differently, as the work exerted by the wing on the surrounding flow field (L/ρ·S), compared against the total kinetic energy required for generating said lift, ½v(2). This reinterpreted coefficient, the normalized lift, is derived from the work-energy theorem and compares the lifting capabilities of dissimilar lift systems on a similar energy footing. The normalized lift is the same as the standard lift coefficient for fixed wings, but differs for wings with more complex motions; it also accounts for such complex motions explicitly and without complex modifications or adjustments. We compare the normalized lift with the previously-reported values of lift coefficient for a rotating cylinder in Magnus effect, a bat during hovering and forward flight, and a hovering dipteran.The maximum standard lift coefficient for a fixed wing without flaps in steady flow is around 1.5, yet for a rotating cylinder it may exceed 9.0, a value that implies that a rotating cylinder generates nearly 6 times the maximum lift of a wing. The maximum normalized lift for a rotating cylinder is 1.5. We suggest that the normalized lift can be used to evaluate propellers, rotors, flapping wings of animals and micro air vehicles, and underwater thrust-generating fins in the same way the lift coefficient is currently used to evaluate fixed wings.

  12. TCA High Lift Preliminary Assessment

    Science.gov (United States)

    Wyatt, G. H.; Polito, R. C.; Yeh, D. T.; Elzey, M. E.; Tran, J. T.; Meredith, Paul T.

    1999-01-01

    This paper presents a TCA (Technology Concept Airplane) High lift Preliminary Assessment. The topics discussed are: 1) Model Description; 2) Data Repeatability; 3) Effect of Inboard L.E. (Leading Edge) Flap Span; 4) Comparison of 14'x22' TCA-1 With NTF (National Transonic Facility) Modified Ref. H; 5) Comparison of 14'x22' and NTF Ref. H Results; 6) Effect of Outboard Sealed Slat on TCA; 7) TCA Full Scale Build-ups; 8) Full Scale L/D Comparisons; 9) TCA Full Scale; and 10) Touchdown Lift Curves. This paper is in viewgraph form.

  13. Endoscopic brow lifts uber alles.

    Science.gov (United States)

    Patel, Bhupendra C K

    2006-12-01

    Innumerable approaches to the ptotic brow and forehead have been described in the past. Over the last twenty-five years, we have used all these techniques in cosmetic and reconstructive patients. We have used the endoscopic brow lift technique since 1995. While no one technique is applicable to all patients, the endoscopic brow lift, with appropriate modifications for individual patients, can be used effectively for most patients with brow ptosis. We present the nuances of this technique and show several different fixation methods we have found useful.

  14. New F-theory lifts

    International Nuclear Information System (INIS)

    Collinucci, Andres

    2009-01-01

    In this note, a procedure is developed to explicitly construct non-trivial F-theory lifts of perturbative IIB orientifold models on Calabi-Yau complete intersections in toric varieties. This procedure works on Calabi-Yau orientifolds where the involution coordinate can have arbitrary projective weight, as opposed to the well-known hypersurface cases where it has half the weight of the equation defining the CY threefold. This opens up the possibility of lifting more general setups, such as models that have O3-planes.

  15. Fuel Cell-Powered Lift Truck Fleet Deployment Projects Final Technical Report May 2014

    Energy Technology Data Exchange (ETDEWEB)

    Klingler, James J [GENCO Infrastructure Solutions, Inc.

    2014-05-06

    The overall objectives of this project were to evaluate the performance, operability and safety of fork lift trucks powered by fuel cells in large distribution centers. This was accomplished by replacing the batteries in over 350 lift trucks with fuel cells at five distribution centers operated by GENCO. The annual cost savings of lift trucks powered by fuel cell power units was between $2,400 and $5,300 per truck compared to battery powered lift trucks, excluding DOE contributions. The greatest savings were in fueling labor costs where a fuel cell powered lift truck could be fueled in a few minutes per day compared to over an hour for battery powered lift trucks which required removal and replacement of batteries. Lift truck operators where generally very satisfied with the performance of the fuel cell power units, primarily because there was no reduction in power over the duration of a shift as experienced with battery powered lift trucks. The operators also appreciated the fast and easy fueling compared to the effort and potential risk of injury associated with switching heavy batteries in and out of lift trucks. There were no safety issues with the fueling or operation of the fuel cells. Although maintenance costs for the fuel cells were higher than for batteries, these costs are expected to decrease significantly in the next generation of fuel cells, making them even more cost effective.

  16. Development of Streamwise Counter-Rotating Vortices in Flat Plate Boundary Layer Pre-set by Leading Edge Patterns

    KAUST Repository

    Hasheminejad, S.M.

    2017-04-03

    Development of streamwise counter-rotating vortices induced by leading edge patterns with different pattern shape is investigated using hot-wire anemometry in the boundary layer of a flat plate. A triangular, sinusoidal and notched patterns with the same pattern wavelength λ of 15mm and the same pattern amplitude A of 7.5mm were examined for free-stream velocity of 3m/s. The results show a good agreement with earlier studies. The inflection point on the velocity profile downstream of the trough of the patterns at the beginning of the vortex formation indicates that the vortices non-linearly propagate downstream. An additional vortex structure was also observed between the troughs of the notched pattern.

  17. The structure of a three-dimensional boundary layer subjected to streamwise-varying spanwise-homogeneous pressure gradient

    International Nuclear Information System (INIS)

    Bentaleb, Y.; Leschziner, M.A.

    2013-01-01

    Highlights: • We study a spatially-evolving three-dimensional boundary layer. • We impose a streamwise-varying spanwise-homogeneous pressure gradient. • A collateral flow is formed close to the wall, and this is investigated alongside the skewed upper part of the boundary layer. • A wide range of flow-physical properties have been studied. -- Abstract: A spatially-evolving three-dimensional boundary layer, subjected to a streamwise-varying spanwise-homogeneous pressure gradient, equivalent to a body force, is investigated by way of direct numerical simulation. The pressure gradient, prescribed to change its sign half-way along the boundary layer, provokes strong skewing of the velocity vector, with a layer of nearly collateral flow forming close to the wall up to the position of maximum spanwise velocity. A wide range of flow-physical properties have been studied, with particular emphasis on the near-wall layer, including second-moments, major budget contributions and wall-normal two-point correlations of velocity fluctuations and their angles, relative to wall-shear fluctuations. The results illustrate the complexity caused by skewing, including a damping in turbulent mixing and a significant lag between strains and stresses. The study has been undertaken in the context of efforts to develop and test novel hybrid LES–RANS schemes for non-equilibrium near-wall flows, with an emphasis on three-dimensional near-wall straining. Fundamental flow-physical issues aside, the data derived should be of particular relevance to a priori studies of second-moment RANS closure and the development and validation of RANS-type near-wall approximations implemented in LES schemes for high-Reynolds-number complex flows

  18. Safe lifting in patients with chronic low back pain : Comparing FCE lifting task and NIOSH lifting guideline

    NARCIS (Netherlands)

    Kuijer, Wietske; Dijkstra, Pieter U.; Brouwer, Sandra; Reneman, Michiel F.; Groothoff, Johan W.; Geertzen, Jan H. B.

    2006-01-01

    Introduction: Both the floor-to-waist lifting task of the Isernhagen Work Systems Functional Capacity Evaluation (IWS FCE) and recommended weight limit (RWL) of the NIOSH produce safe lifting weights and are used world-wide nowadays. It is unknown whether they produce similar safe lifting weights.

  19. Fuel Cell Hydroge Manifold for Lift Trucks

    DEFF Research Database (Denmark)

    Hosseinzadeh, Elham

    . Battery driven lift trucks are being used more and more in different companies to reduce their emissions. However, battery driven lift trucks need long time to recharge and may be out of work for a long time. Fuel cell driven lift trucks diminish this problem and are therefore getting more attention...

  20. Laser-induced forward transfer (LIFT) of congruent voxels

    Science.gov (United States)

    Piqué, Alberto; Kim, Heungsoo; Auyeung, Raymond C. Y.; Beniam, Iyoel; Breckenfeld, Eric

    2016-06-01

    Laser-induced forward transfer (LIFT) of functional materials offers unique advantages and capabilities for the rapid prototyping of electronic, optical and sensor elements. The use of LIFT for printing high viscosity metallic nano-inks and nano-pastes can be optimized for the transfer of voxels congruent with the shape of the laser pulse, forming thin film-like structures non-lithographically. These processes are capable of printing patterns with excellent lateral resolution and thickness uniformity typically found in 3-dimensional stacked assemblies, MEMS-like structures and free-standing interconnects. However, in order to achieve congruent voxel transfer with LIFT, the particle size and viscosity of the ink or paste suspensions must be adjusted to minimize variations due to wetting and drying effects. When LIFT is carried out with high-viscosity nano-suspensions, the printed voxel size and shape become controllable parameters, allowing the printing of thin-film like structures whose shape is determined by the spatial distribution of the laser pulse. The result is a new level of parallelization beyond current serial direct-write processes whereby the geometry of each printed voxel can be optimized according to the pattern design. This work shows how LIFT of congruent voxels can be applied to the fabrication of 2D and 3D microstructures by adjusting the viscosity of the nano-suspension and laser transfer parameters.

  1. Lifting device for drilling rods

    Energy Technology Data Exchange (ETDEWEB)

    Radzivilovich, L L; Laptev, A G; Lipkovich, V A

    1982-01-01

    A lifter is proposed for drilling rods including a spacer stand with rotating bracket, boom with by-pass rollers, spacing and lifting hydrocylinders with rods and flexible tie mechanism. In order to improve labor productivity by improving maneuverability and to increase the maintenance zone, the lifter is equipped with a hydrocylinder of advance and a cross piece which is installed with the possibility of forward and rotational movement on the stand, and in which by means of the hydrocylinder of advance a boom is attached. Within the indicated boom there is a branch of the flexible tie mechanism with end attached with the possibility of regulation over the length on a rotating bracket, while the rod of the lifting hydrocylinder is connected to the cross piece.

  2. First-Order Twistor Lifts

    Directory of Open Access Journals (Sweden)

    Simões BrunoAscenso

    2010-01-01

    Full Text Available The use of twistor methods in the study of Jacobi fields has proved quite fruitful, leading to a series of results. L. Lemaire and J. C. Wood proved several properties of Jacobi fields along harmonic maps from the two-sphere to the complex projective plane and to the three- and four-dimensional spheres, by carefully relating the infinitesimal deformations of the harmonic maps to those of the holomorphic data describing them. In order to advance this programme, we prove a series of relations between infinitesimal properties of the map and those of its twistor lift. Namely, we prove that isotropy and harmonicity to first order of the map correspond to holomorphicity to first order of its lift into the twistor space, relatively to the standard almost complex structures and . This is done by obtaining first-order analogues of classical twistorial constructions.

  3. First-Order Twistor Lifts

    Directory of Open Access Journals (Sweden)

    Bruno Ascenso Simões

    2010-01-01

    Full Text Available The use of twistor methods in the study of Jacobi fields has proved quite fruitful, leading to a series of results. L. Lemaire and J. C. Wood proved several properties of Jacobi fields along harmonic maps from the two-sphere to the complex projective plane and to the three- and four-dimensional spheres, by carefully relating the infinitesimal deformations of the harmonic maps to those of the holomorphic data describing them. In order to advance this programme, we prove a series of relations between infinitesimal properties of the map and those of its twistor lift. Namely, we prove that isotropy and harmonicity to first order of the map correspond to holomorphicity to first order of its lift into the twistor space, relatively to the standard almost complex structures J1 and J2. This is done by obtaining first-order analogues of classical twistorial constructions.

  4. The Effect of Lifting Speed on Cumulative and Peak Biomechanical Loading for Symmetric Lifting Tasks

    Directory of Open Access Journals (Sweden)

    Kasey O. Greenland

    2013-06-01

    Conclusion: Based on peak values, BCF is highest for fast speeds, but the BCF cumulative loading is highest for slow speeds, with the largest difference between fast and slow lifts. This may imply that a slow lifting speed is at least as hazardous as a fast lifting speed. It is important to consider the duration of lift when determining risks for back and shoulder injuries due to lifting and that peak values alone are likely not sufficient.

  5. New heavy-lift system under construction

    Energy Technology Data Exchange (ETDEWEB)

    2009-07-01

    Heavy-lift availability is at a premium, and the market is eager for alternatives to meet the demand. An alternative heavy-lift solution from SeaMetric - which has two multi-purpose heavy-lift vessels under construction in China - will be available in the first quarter of 2011. The TML system is based on buoyancy and ballast tanks, with four lifting arms mounted on two identical vessels, each vessel measuring 140 x 40 x 10.75 metres. To perform a lift, one TML with lifting arms is positioned on each side of the object. Using seawater pumps, lift force is created by de ballasting the buoyancy tanks and at the same time ballasting the ballast tanks. (AG). tab., ills

  6. Variable Lifting Index (VLI): A New Method for Evaluating Variable Lifting Tasks.

    Science.gov (United States)

    Waters, Thomas; Occhipinti, Enrico; Colombini, Daniela; Alvarez-Casado, Enrique; Fox, Robert

    2016-08-01

    We seek to develop a new approach for analyzing the physical demands of highly variable lifting tasks through an adaptation of the Revised NIOSH (National Institute for Occupational Safety and Health) Lifting Equation (RNLE) into a Variable Lifting Index (VLI). There are many jobs that contain individual lifts that vary from lift to lift due to the task requirements. The NIOSH Lifting Equation is not suitable in its present form to analyze variable lifting tasks. In extending the prior work on the VLI, two procedures are presented to allow users to analyze variable lifting tasks. One approach involves the sampling of lifting tasks performed by a worker over a shift and the calculation of the Frequency Independent Lift Index (FILI) for each sampled lift and the aggregation of the FILI values into six categories. The Composite Lift Index (CLI) equation is used with lifting index (LI) category frequency data to calculate the VLI. The second approach employs a detailed systematic collection of lifting task data from production and/or organizational sources. The data are organized into simplified task parameter categories and further aggregated into six FILI categories, which also use the CLI equation to calculate the VLI. The two procedures will allow practitioners to systematically employ the VLI method to a variety of work situations where highly variable lifting tasks are performed. The scientific basis for the VLI procedure is similar to that for the CLI originally presented by NIOSH; however, the VLI method remains to be validated. The VLI method allows an analyst to assess highly variable manual lifting jobs in which the task characteristics vary from lift to lift during a shift. © 2015, Human Factors and Ergonomics Society.

  7. Normalized Lift: An Energy Interpretation of the Lift Coefficient Simplifies Comparisons of the Lifting Ability of Rotating and Flapping Surfaces

    OpenAIRE

    Burgers, Phillip; Alexander, David E.

    2012-01-01

    For a century, researchers have used the standard lift coefficient C(L) to evaluate the lift, L, generated by fixed wings over an area S against dynamic pressure, ½ρv(2), where v is the effective velocity of the wing. Because the lift coefficient was developed initially for fixed wings in steady flow, its application to other lifting systems requires either simplifying assumptions or complex adjustments as is the case for flapping wings and rotating cylinders.This paper interprets the standar...

  8. Electro—magnetic control of shear flow over a cylinder for drag reduction and lift enhancement

    International Nuclear Information System (INIS)

    Zhang Hui; Fan Bao-Chun; Chen Zhi-Hua; Chen Shuai; Li Hong-Zhi

    2013-01-01

    In this paper, the electro—magnetic control of a cylinder wake in shear flow is investigated numerically. The effects of the shear rate and Lorentz force on the cylinder wake, the distribution of hydrodynamic force, and the drag/lift phase diagram are discussed in detail. It is revealed that Lorentz force can be classified into the field Lorentz force and the wall Lorentz force and they affect the drag and lift forces independently. The drag/lift phase diagram with a shape of ''8'' consists of two closed curves, which correspond to the halves of the shedding cycle dominated by the upper and lower vortices respectively. The free stream shear (K > 0) induces the diagram to move downward and leftward, so that the average lift force directs toward the downside. With the upper Lorentz force, the diagram moves downwards and to the right by the field Lorentz force, thus resulting in the drag increase and the lift reduction, whereas it moves upward and to the left by the wall Lorentz force, leading to the drag reduction and the lift increase. Finally the diagram is dominated by the wall Lorentz force, thus moving upward and leftward. Therefore the upper Lorentz force, which enhances the lift force, can be used to overcome the lift loss due to the free stream shear, which is also obtained in the experiment. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  9. Isolated neck-lifting procedure: isolated stork lift.

    Science.gov (United States)

    Barbarino, Sheila C; Wu, Allan Y; Morrow, David M

    2013-04-01

    Many patients desire cosmetic improvement of neck laxity when consulting with a plastic surgeon about their face. Neck laxity and loss of the cervicomental angle can be due to multiple components of aging such as skin quality/elasticity, loss of platysma muscle tone, and submental fat accumulation. Traditionally, the procedure of choice for patients with an aging lower face and neck is a cervicofacial rhytidectomy. However, occasionally, a patient wishes to have no other facial surgery than an improvement of their excessive skin of the anterior, lateral, and/or posterior neck. In other instances, a patient may present with having had a face/neck-lifting procedure that left objectionable vertical/diagonal lines at the lateral neck. In both these instances, a surgeon should consider an isolated stork lift (ISL) procedure. An ISL procedure avoids and/or corrects problematic vertical/diagonal lateral neck folds by "walking" the excess skin flaps around the posterior inferior occipital hairline bilaterally, bringing the flaps together at the lateral and posterior neck, which sometimes involves a midline posterior dart excision of the dog ear. A patient presenting with excessive skin of the neck (anterior, lateral, and/or posterior) and/or residual vertical/diagonal skin folds is an excellent candidate for the ISL. The ISL procedure was performed on 273 patients over a 2-year period at The Morrow Institute. Patients were included if they had excessive skin of the anterior, lateral, and/or posterior neck and/or diagonal/vertical lateral bands and did not desire a full face-lifting procedure. Patients were excluded from this study if they would not accept having longer hair in order to cover the scar along the posterior inferior occipital hairline or a midline T-flap skin closure scar at the base of the posterior midline neck. Under a combination of local anesthesia and IV sedation, a postauricular face-lift incision was made that was extended in a circumoccipital fashion

  10. The Influence of Chordwise Flexibility on the Flow Structure and Streamwise Force of a Sinusoidally Pitching Airfoil

    Science.gov (United States)

    Olson, David Arthur

    Many natural flyers and swimmers need to exploit unsteady mechanisms in order to generate sufficient aerodynamic forces for sustained flight and propulsion. This is, in part, due to the low speed and length scales at which they typically operate. In this low Reynolds number regime, there are many unanswered questions on how existing aerodynamic theory for both steady and unsteady flows can be applied. Additionally, most of these natural flyers and swimmers have deformable wing/fin structures, three dimensional wing planforms, and exhibit complex kinematics during motion. While some biologically-inspired studies seek to replicate these complex structures and kinematics in the laboratory or in numerical simulations, it becomes difficult to draw explicit connections to the existing knowledge base of classical unsteady aerodynamic theory due to the complexity of the problems. In this experimental study, wing kinematics, structure, and planform are greatly simplified to investigate the effect of chordwise flexibility on the streamwise force (thrust) and wake behavior of a sinusoidally pitching airfoil. The study of flexibility in the literature has typically utilized flat plates with varying thicknesses or lengths to change their chordwise flexibility. This choice introduces additional complexities when comparing to the wealth of knowledge originally developed on streamlined aerodynamic shapes. The current study capitalizes on the recent developments in 3D printer technology to create accurate shapes out of materials with varying degrees of flexibility by creating two standard NACA 0009 airfoils: one rigid and one flexible. Each of the two airfoils are sinusoidally pitched about the quarter chord over a range of oscillation amplitudes and frequencies while monitoring the deformation of the airfoil. The oscillation amplitude is selected to be small enough such that leading edge vortices do not form, and the vortical structures in the wake are formed from the trailing

  11. Experimental Studies of Low-Pressure Turbine Flows and Flow Control. Streamwise Pressure Profiles and Velocity Profiles

    Science.gov (United States)

    Volino, Ralph

    2012-01-01

    faculties. The geometry corresponded to "Pak B" LPT airfoil. The test section simulated LPT flow in a passage. Three experimental studies were performed: (a) Boundary layer measurements for ten baseline cases under high and low freestream turbulence conditions at five Reynolds numbers of 25,000, 50,000, 100,000, 200,000, and 300,000, based on passage exit velocity and suction surface wetted length; (b) Passive flow control studies with three thicknesses of two-dimensional bars, and two heights of three-dimensional circular cylinders with different spanwise separations, at same flow conditions as the 10 baseline cases; (c) Active flow control with oscillating synthetic (zero net mass flow) vortex generator jets, for one case with low freestream turbulence and a low Reynolds number of 25,000. The Passive flow control was successful at controlling the separation problem at low Reynolds numbers, with varying degrees of success from case to case and varying levels of impact at higher Reynolds numbers. The active flow control successfully eliminated the large separation problem for the low Reynolds number case. Very detailed data was acquired using hot-wire anemometry, including single and two velocity components, integral boundary layer quantities, turbulence statistics and spectra, turbulent shear stresses and their spectra, and intermittency, documenting transition, separation and reattachment. Models were constructed to correlate the results. The report includes a summary of the work performed and reprints of the publications describing the various studies. The folders in this supplement contain processed data in ASCII format. Streamwise pressure profiles and velocity profiles are included. The velocity profiles were acquired using single sensor and cross sensor hot-wire probes which were traversed from the wall to the freestream at various streamwise locations. In some of the flow control cases (3D Trips and Jets) profiles were acquired at multiple spanwise locations.

  12. Scaling of lifting forces in relation to object size in whole body lifting

    NARCIS (Netherlands)

    Kingma, I.; van Dieen, J.H.; Toussaint, H.M.

    2005-01-01

    Subjects prepare for a whole body lifting movement by adjusting their posture and scaling their lifting forces to the expected object weight. The expectancy is based on visual and haptic size cues. This study aimed to find out whether lifting force overshoots related to object size cues disappear or

  13. 33 CFR 118.85 - Lights on vertical lift bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on vertical lift bridges... BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.85 Lights on vertical lift bridges. (a) Lift span lights. The vertical lift span of every vertical lift bridge shall be lighted so that the center of the...

  14. Complex multiplication and lifting problems

    CERN Document Server

    Chai, Ching-Li; Oort, Frans

    2013-01-01

    Abelian varieties with complex multiplication lie at the origins of class field theory, and they play a central role in the contemporary theory of Shimura varieties. They are special in characteristic 0 and ubiquitous over finite fields. This book explores the relationship between such abelian varieties over finite fields and over arithmetically interesting fields of characteristic 0 via the study of several natural CM lifting problems which had previously been solved only in special cases. In addition to giving complete solutions to such questions, the authors provide numerous examples to illustrate the general theory and present a detailed treatment of many fundamental results and concepts in the arithmetic of abelian varieties, such as the Main Theorem of Complex Multiplication and its generalizations, the finer aspects of Tate's work on abelian varieties over finite fields, and deformation theory. This book provides an ideal illustration of how modern techniques in arithmetic geometry (such as descent the...

  15. Soccer Ball Lift Coefficients via Trajectory Analysis

    Science.gov (United States)

    Goff, John Eric; Carre, Matt J.

    2010-01-01

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin…

  16. Thermally stimulating mechanically-lifted well production

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, E.A.; Hinson, R.A.

    1984-06-19

    A well which is producing slowly by artificial lift can be economically heated by first inflowing a nitrogen-generating solution, to form a pool of reacting liquid near the uppermost opening into the reservoir, then inflowing more solution while artificially-lifting liquid from near the lowermost opening into the reservoir at a rate substantially equalling the inflow rate.

  17. Local vibrations and lift performance of low Reynolds number airfoil

    Directory of Open Access Journals (Sweden)

    TariqAmin Khan

    2017-06-01

    Full Text Available The 2D incompressible Navier-Stokes equations are solved based on the finite volume method and dynamic mesh technique is used to carry out partial fluid structure interaction. The local flexible structure (hereinafter termed as flexible structure vibrates in a single mode located on the upper surface of the airfoil. The Influence of vibration frequency and amplitude are examined and the corresponding fluid flow characteristics are investigated which add complexity to the inherent problem in unsteady flow. The study is conducted for flow over NACA0012 airfoil at 600≤Re≤3000 at a low angle of attack. Vibration of flexible structure induces a secondary vortex which modifies the pressure distribution and lift performance of the airfoil. At some moderate vibration amplitude, frequency synchronization or lock-in phenomenon occurs when the vibration frequency is close to the characteristic frequency of rigid airfoil. Evolution and shedding of vortices corresponding to the deformation of flexible structure depends on the Reynolds number. In the case of Re≤1000, the deformation of flexible structure is considered in-phase with the vortex shedding i.e., increasing maximum lift is linked with the positive deformation of flexible structure. At Re=1500 a phase shift of about 1/π exists while they are out-of-phase at Re>1500. Moreover, the oscillation amplitude of lift coefficient increases with increasing vibration amplitude for Re≤1500 while it decreases with increasing vibration amplitude for Re>1500. As a result of frequency lock-in, the average lift coefficient is increased with increasing vibration amplitude for all investigated Reynolds numbers (Re. The maximum increase in the average lift coefficient is 19.72% within the range of investigated parameters.

  18. Lift conference | 5-7 February

    CERN Multimedia

    2014-01-01

    Since 2006, Lift Events explore the business and social implications of new technologies through the organisation of international event series and open innovation programs in Europe, Asia and America. The next conference will be held on 5-7 February in Geneva.   (Image: © Lift Conference) The Lift Conference is one of the leading conferences on innovation in Europe and a key annual meeting for individuals and organizations wishing to understand and anticipate trends and innovation. Held every year in February in Geneva (5-7 February 2014), the Lift Conference is a three-day event consisting of talks, interactive workshops, exhibitions, and discussions bringing together over 1’000 participants from all society’s sectors and industries in a dynamic and informal environment with the aim to learn, connect, share and leverage innovation opportunities.   Extraordinary speakers will take to the stage at Lift14: Porter Erisman, former VP of Alibaba.com turned...

  19. Lambda-Lifting in Quadratic Time

    DEFF Research Database (Denmark)

    Danvy, Olivier; Schultz, Ulrik Pagh

    2002-01-01

    Lambda-lifting is a program transformation that is used in compilers, partial evaluators, and program transformers. In this article, we show how to reduce its complexity from cubic time to quadratic time, and we present a flow-sensitive lambda-lifter that also works in quadratic time. Lambda-lifting...... that yields the cubic factor in the traditional formulation of lambda-lifting, which is due to Johnsson. This search is carried out by computing a transitive closure. To reduce the complexity of lambda-lifting, we partition the call graph of the source program into strongly connected components, based...... of lambda-lifting from O(n^3) to O(n^2) . where n is the size of the program. Since a lambda-lifter can output programs of size O(n^2), our algorithm is asympotically optimal....

  20. Lambda-Lifting in Quadratic Time

    DEFF Research Database (Denmark)

    Danvy, Olivier; Schultz, Ulrik Pagh

    2003-01-01

    Lambda-lifting is a program transformation that is used in compilers, partial evaluators, and program transformers. In this article, we show how to reduce its complexity from cubic time to quadratic time, and we present a flow-sensitive lambda-lifter that also works in quadratic time. Lambda-lifting...... that yields the cubic factor in the traditional formulation of lambda-lifting, which is due to Johnsson. This search is carried out by computing a transitive closure. To reduce the complexity of lambda-lifting, we partition the call graph of the source program into strongly connected components, based...... of lambda-lifting from O(n^3) to O(n^2) . where n is the size of the program. Since a lambda-lifter can output programs of size O(n^2), our algorithm is asympotically optimal....

  1. Occupational lifting and pelvic pain during pregnancy:

    DEFF Research Database (Denmark)

    Larsen, Pernille Stemann; Strandberg-Larsen, Katrine; Juhl, Mette

    2013-01-01

    OBJECTIVES: Pelvic pain during pregnancy is a common ailment, and the disease is a major cause of sickness absence during pregnancy. It is plausible that occupational lifting may be a risk factor of pelvic pain during pregnancy, but no previous studies have examined this specific exposure. The aim...... of this study was to examine the association between occupational lifting and pelvic pain during pregnancy. METHODS: The study comprised 50 143 pregnant women, enrolled in the Danish National Birth Cohort in the period from 1996-2002. During pregnancy, the women provided information on occupational lifting...... (weight load and daily frequency), and six months post partum on pelvic pain. Adjusted odds ratios for pelvic pain during pregnancy according to occupational lifting were calculated by logistic regression. RESULTS: Any self-reported occupational lifting (>1 time/day and loads weighing >10 kg...

  2. Lambda-Lifting in Quadratic Time

    DEFF Research Database (Denmark)

    Danvy, Olivier; Schultz, Ulrik Pagh

    2004-01-01

    Lambda-lifting is a program transformation that is used in compilers, partial evaluators, and program transformers. In this article, we show how to reduce its complexity from cubic time to quadratic time, and we present a flow-sensitive lambda-lifter that also works in quadratic time. Lambda-lifting...... that yields the cubic factor in the traditional formulation of lambda-lifting, which is due to Johnsson. This search is carried out by computing a transitive closure. To reduce the complexity of lambda-lifting, we partition the call graph of the source program into strongly connected components, based...... of lambda-lifting from O(n^3) to O(n^2) . where n is the size of the program. Since a lambda-lifter can output programs of size O(n^2), our algorithm is asympotically optimal....

  3. Direct lifts of coupled cell networks

    Science.gov (United States)

    Dias, A. P. S.; Moreira, C. S.

    2018-04-01

    In networks of dynamical systems, there are spaces defined in terms of equalities of cell coordinates which are flow-invariant under any dynamical system that has a form consistent with the given underlying network structure—the network synchrony subspaces. Given a network and one of its synchrony subspaces, any system with a form consistent with the network, restricted to the synchrony subspace, defines a new system which is consistent with a smaller network, called the quotient network of the original network by the synchrony subspace. Moreover, any system associated with the quotient can be interpreted as the restriction to the synchrony subspace of a system associated with the original network. We call the larger network a lift of the smaller network, and a lift can be interpreted as a result of the cellular splitting of the smaller network. In this paper, we address the question of the uniqueness in this lifting process in terms of the networks’ topologies. A lift G of a given network Q is said to be direct when there are no intermediate lifts of Q between them. We provide necessary and sufficient conditions for a lift of a general network to be direct. Our results characterize direct lifts using the subnetworks of all splitting cells of Q and of all split cells of G. We show that G is a direct lift of Q if and only if either the split subnetwork is a direct lift or consists of two copies of the splitting subnetwork. These results are then applied to the class of regular uniform networks and to the special classes of ring networks and acyclic networks. We also illustrate that one of the applications of our results is to the lifting bifurcation problem.

  4. Lifting index of the niosh lifting equation and low back pain

    Directory of Open Access Journals (Sweden)

    Eliana Remor Teixeira

    2011-09-01

    Full Text Available The purpose of this study is to assess the relationship of the Lifting Index obtained through the application of the NIOSH Lifting Equation and the incidence of low back pain among forty-eight workers involved in manual lifting tasks. It was applied the equation in eleven tasks and the workers were interviewed. The most unfavorable conditions presented themselves in the lifting destination. The variables that most contributed to the inadequate values of the Lifting Index were: the horizontal location, the lifting frequency and the vertical distance, beyond the high weight of the load. The incidence of low back pain in the last twelve months was 19%, whereas the incidence of work-related low back pain in the same period was 10%. In 72.7% of the tasks evaluated the Composite Lifting Index was more than three, which are considered as high ergonomic risk.

  5. Occupational lifting of heavy loads and preterm birth:

    DEFF Research Database (Denmark)

    Runge, Stine Bjerrum; Pedersen, Jacob Krabbe; Svendsen, Susanne Wulff

    2013-01-01

    To examine the association between occupational lifting during pregnancy and preterm birth. The risk of preterm birth was estimated for total burden lifted per day and number of medium and heavy loads lifted per day.......To examine the association between occupational lifting during pregnancy and preterm birth. The risk of preterm birth was estimated for total burden lifted per day and number of medium and heavy loads lifted per day....

  6. Lift hysteresis at stall as an unsteady boundary-layer phenomenon

    Science.gov (United States)

    Moore, Franklin K

    1956-01-01

    Analysis of rotating stall of compressor blade rows requires specification of a dynamic lift curve for the airfoil section at or near stall, presumably including the effect of lift hysteresis. Consideration of the magnus lift of a rotating cylinder suggests performing an unsteady boundary-layer calculation to find the movement of the separation points of an airfoil fixed in a stream of variable incidence. The consideration of the shedding of vorticity into the wake should yield an estimate of lift increment proportional to time rate of change of angle of attack. This increment is the amplitude of the hysteresis loop. An approximate analysis is carried out according to the foregoing ideas for a 6:1 elliptic airfoil at the angle of attack for maximum lift. The assumptions of small perturbations from maximum lift are made, permitting neglect of distributed vorticity in the wake. The calculated hysteresis loop is counterclockwise. Finally, a discussion of the forms of hysteresis loops is presented; and, for small reduced frequency of oscillation, it is concluded that the concept of a viscous "time lag" is appropriate only for harmonic variations of angle of attack with time at mean conditions other than maximum lift.

  7. Modeling lift operations with SASmacr Simulation Studio

    Science.gov (United States)

    Kar, Leow Soo

    2016-10-01

    Lifts or elevators are an essential part of multistorey buildings which provide vertical transportation for its occupants. In large and high-rise apartment buildings, its occupants are permanent, while in buildings, like hospitals or office blocks, the occupants are temporary or users of the buildings. They come in to work or to visit, and thus, the population of such buildings are much higher than those in residential apartments. It is common these days that large office blocks or hospitals have at least 8 to 10 lifts serving its population. In order to optimize the level of service performance, different transportation schemes are devised to control the lift operations. For example, one lift may be assigned to solely service the even floors and another solely for the odd floors, etc. In this paper, a basic lift system is modelled using SAS Simulation Studio to study the effect of factors such as the number of floors, capacity of the lift car, arrival rate and exit rate of passengers at each floor, peak and off peak periods on the system performance. The simulation is applied to a real lift operation in Sunway College's North Building to validate the model.

  8. Wingless Flight: The Lifting Body Story

    Science.gov (United States)

    Reed, R. Dale; Lister, Darlene (Editor); Huntley, J. D. (Editor)

    1997-01-01

    Wingless Flight tells the story of the most unusual flying machines ever flown, the lifting bodies. It is my story about my friends and colleagues who committed a significant part of their lives in the 1960s and 1970s to prove that the concept was a viable one for use in spacecraft of the future. This story, filled with drama and adventure, is about the twelve-year period from 1963 to 1975 in which eight different lifting-body configurations flew. It is appropriate for me to write the story, since I was the engineer who first presented the idea of flight-testing the concept to others at the NASA Flight Research Center. Over those twelve years, I experienced the story as it unfolded day by day at that remote NASA facility northeast of los Angeles in the bleak Mojave Desert. Benefits from this effort immediately influenced the design and operational concepts of the winged NASA Shuttle Orbiter. However, the full benefits would not be realized until the 1990s when new spacecraft such as the X-33 and X-38 would fully employ the lifting-body concept. A lifting body is basically a wingless vehicle that flies due to the lift generated by the shape of its fuselage. Although both a lifting reentry vehicle and a ballistic capsule had been considered as options during the early stages of NASA's space program, NASA initially opted to go with the capsule. A number of individuals were not content to close the book on the lifting-body concept. Researchers including Alfred Eggers at the NASA Ames Research Center conducted early wind-tunnel experiments, finding that half of a rounded nose-cone shape that was flat on top and rounded on the bottom could generate a lift-to-drag ratio of about 1.5 to 1. Eggers' preliminary design sketch later resembled the basic M2 lifting-body design. At the NASA Langley Research Center, other researchers toyed with their own lifting-body shapes. Meanwhile, some of us aircraft-oriented researchers at the, NASA Flight Research Center at Edwards Air

  9. Electromagnetic nondestructive testing at high lift-off using a magnetic image conduit

    International Nuclear Information System (INIS)

    Lee, Jin Yi; Jun, Jong Woo; Kim, Jung Min; Le, Min Hhuy

    2013-01-01

    To protect sensors from the extreme environments, such as, heat, moisture, pollution and radiation, cracks must be inspected for; this can be done by measuring the distribution of magnetic fields at high lift-off through nondestructive electro-magnetic testing. However, as the intensity of an electro-magnetic field is inversely proportional to the square of the lift-off, it becomes increasingly difficult to effective inspect a crack as the lift-off increases. In this paper, a magnetic image conduit to minimize the intensity loss of an electro-magnetic field at high lift-off is proposed, and the effectiveness of a conduit for magnetic imaging is verified by means of both theoretical and experimental approaches.

  10. Laser-induced forward transfer (LIFT) of congruent voxels

    Energy Technology Data Exchange (ETDEWEB)

    Piqué, Alberto, E-mail: pique@nrl.navy.mil [Materials Science and Technology Division, Code 6364, Naval Research Laboratory, Washington, DC 20375 (United States); Kim, Heungsoo; Auyeung, Raymond C.Y.; Beniam, Iyoel [Materials Science and Technology Division, Code 6364, Naval Research Laboratory, Washington, DC 20375 (United States); Breckenfeld, Eric [National Research Council Fellow at the Naval Research Laboratory, Washington, DC 20375 (United States)

    2016-06-30

    Highlights: • Laser-induced forward transfer (LIFT) is demonstrated with high viscosity Ag nanopaste. • Under the right conditions (viscosity and fluence) the transfer of congruent voxels was achieved. • For viscosities under 100 Pa s, congruent voxel transfer of silver nano-suspensions is only possible under a very narrow range of conditions. • For viscosities over 100 Pa s, congruent voxel transfer of silver nano-pastes works over a wider range of fluences, donor substrate thickness, gap distances and voxel areas. • The laser transfer of congruent voxels can be used for printing electronic patterns in particular interconnects. - Abstract: Laser-induced forward transfer (LIFT) of functional materials offers unique advantages and capabilities for the rapid prototyping of electronic, optical and sensor elements. The use of LIFT for printing high viscosity metallic nano-inks and nano-pastes can be optimized for the transfer of voxels congruent with the shape of the laser pulse, forming thin film-like structures non-lithographically. These processes are capable of printing patterns with excellent lateral resolution and thickness uniformity typically found in 3-dimensional stacked assemblies, MEMS-like structures and free-standing interconnects. However, in order to achieve congruent voxel transfer with LIFT, the particle size and viscosity of the ink or paste suspensions must be adjusted to minimize variations due to wetting and drying effects. When LIFT is carried out with high-viscosity nano-suspensions, the printed voxel size and shape become controllable parameters, allowing the printing of thin-film like structures whose shape is determined by the spatial distribution of the laser pulse. The result is a new level of parallelization beyond current serial direct-write processes whereby the geometry of each printed voxel can be optimized according to the pattern design. This work shows how LIFT of congruent voxels can be applied to the fabrication of 2D

  11. Laser-induced forward transfer (LIFT) of congruent voxels

    International Nuclear Information System (INIS)

    Piqué, Alberto; Kim, Heungsoo; Auyeung, Raymond C.Y.; Beniam, Iyoel; Breckenfeld, Eric

    2016-01-01

    Highlights: • Laser-induced forward transfer (LIFT) is demonstrated with high viscosity Ag nanopaste. • Under the right conditions (viscosity and fluence) the transfer of congruent voxels was achieved. • For viscosities under 100 Pa s, congruent voxel transfer of silver nano-suspensions is only possible under a very narrow range of conditions. • For viscosities over 100 Pa s, congruent voxel transfer of silver nano-pastes works over a wider range of fluences, donor substrate thickness, gap distances and voxel areas. • The laser transfer of congruent voxels can be used for printing electronic patterns in particular interconnects. - Abstract: Laser-induced forward transfer (LIFT) of functional materials offers unique advantages and capabilities for the rapid prototyping of electronic, optical and sensor elements. The use of LIFT for printing high viscosity metallic nano-inks and nano-pastes can be optimized for the transfer of voxels congruent with the shape of the laser pulse, forming thin film-like structures non-lithographically. These processes are capable of printing patterns with excellent lateral resolution and thickness uniformity typically found in 3-dimensional stacked assemblies, MEMS-like structures and free-standing interconnects. However, in order to achieve congruent voxel transfer with LIFT, the particle size and viscosity of the ink or paste suspensions must be adjusted to minimize variations due to wetting and drying effects. When LIFT is carried out with high-viscosity nano-suspensions, the printed voxel size and shape become controllable parameters, allowing the printing of thin-film like structures whose shape is determined by the spatial distribution of the laser pulse. The result is a new level of parallelization beyond current serial direct-write processes whereby the geometry of each printed voxel can be optimized according to the pattern design. This work shows how LIFT of congruent voxels can be applied to the fabrication of 2D

  12. Reinforced orbitotemporal lift: contribution to midface rejuvenation.

    Science.gov (United States)

    Renó, Waldir Teixeira

    2003-02-01

    The changes in the aging face occur from progressive ptosis of the skin, fat, and muscle, in conjunction with bone absorption and cartilage atrophy. In the orbital region, hollowness and compartmentalization occur. Conventional face lift procedures correct only the skin flaccidity, and superficial musculoaponeurotic system techniques reposition the skin and platysma without repositioning the middle third of the face, creating an artificial jawline. Subperiosteal rhytidectomy disrupts the anatomy of the periorbita, which gives the patient a certain scarecrow aspect. Composite rhytidectomy associated with brow lift and blepharoplasty may offer better results, with improvement in the malar and orbital regions. The reinforced orbitotemporal lift (ROTEL) is a new procedure in a face lift that allows the orbicularis oculi muscle and all the structures connected to it to be elevated and stretched and the orbitotemporal skin to be raised, repositioning these structures and ending orbital compartmentalization. The result is an impressive improvement in the malar-orbitotemporal region, resulting in a natural and youthful appearance.

  13. Lambda-lifting in Quadratic Time

    DEFF Research Database (Denmark)

    Danvy, O.; Schultz, U.P.

    2004-01-01

    -lifting transforms a block-structured program into a set of recursive equations, one for each local function in the source program. Each equation carries extra parameters to account for the free variables of the corresponding local function and of all its callees. It is the search for these extra parameters......Lambda-lifting is a program transformation that is used in compilers, partial evaluators, and program transformers. In this article, we show how to reduce its complexity from cubic time to quadratic time, and we present a flow-sensitive lambda-lifter that also works in quadratic time. Lambda...... that yields the cubic factor in the traditional formulation of lambda-lifting, which is due to Johnsson. This search is carried out by computing a transitive closure. To reduce the complexity of lambda-lifting, we partition the call graph of the source program into strongly connected components, based...

  14. Design of heavy lift cargo aircraft

    Data.gov (United States)

    National Aeronautics and Space Administration — This is the bird of the skies of the future. The heavy lift cargo aircraft which is currently being developed by me has twice the payload capacity of an Antonov...

  15. Lift : Special Needs Transportation in Portland, Oregon

    Science.gov (United States)

    1978-01-01

    The report covers Portland, Oregon's Special Needs Transportation (SNT) project - the Lift - during its first year of operation. The purposes of this UMTA Service and Methods Demonstration (SMD) is to: (1) test a transit operator's ability to provide...

  16. Lower complexity bounds for lifted inference

    DEFF Research Database (Denmark)

    Jaeger, Manfred

    2015-01-01

    instances of the model. Numerous approaches for such “lifted inference” techniques have been proposed. While it has been demonstrated that these techniques will lead to significantly more efficient inference on some specific models, there are only very recent and still quite restricted results that show...... the feasibility of lifted inference on certain syntactically defined classes of models. Lower complexity bounds that imply some limitations for the feasibility of lifted inference on more expressive model classes were established earlier in Jaeger (2000; Jaeger, M. 2000. On the complexity of inference about...... that under the assumption that NETIME≠ETIME, there is no polynomial lifted inference algorithm for knowledge bases of weighted, quantifier-, and function-free formulas. Further strengthening earlier results, this is also shown to hold for approximate inference and for knowledge bases not containing...

  17. Spherical projections and liftings in geometric tomography

    DEFF Research Database (Denmark)

    Goodey, Paul; Kiderlen, Markus; Weil, Wolfgang

    2011-01-01

    We consider a variety of integral transforms arising in Geometric Tomography. It will be shown that these can be put into a common framework using spherical projection and lifting operators. These operators will be applied to support functions and surface area measures of convex bodies and to rad......We consider a variety of integral transforms arising in Geometric Tomography. It will be shown that these can be put into a common framework using spherical projection and lifting operators. These operators will be applied to support functions and surface area measures of convex bodies...... and to radial functions of star bodies. We then investigate averages of lifted projections and show that they correspond to self-adjoint intertwining operators. We obtain formulas for the eigenvalues of these operators and use them to ascertain circumstances under which tomographic measurements determine...... the original bodies. This approach via mean lifted projections leads us to some unexpected relationships between seemingly disparate geometric constructions....

  18. Lambda-Lifting in Quadratic Time

    DEFF Research Database (Denmark)

    Danvy, Olivier; Schultz, Ulrik Pagh

    2002-01-01

    Lambda-lifting is a program transformation used in compilers and in partial evaluators and that operates in cubic time. In this article, we show how to reduce this complexity to quadratic time. Lambda-lifting transforms a block-structured program into a set of recursive equations, one for each...... local function in the source program. Each equation carries extra parameters to account for the free variables of the corresponding local function and of all its callees. It is the search for these extra parameters that yields the cubic factor in the traditional formulation of lambda-lifting, which...... is not needed. We therefore simplify the search for extra parameters by treating each strongly connected component instead of each function as a unit, thereby reducing the time complexity of lambda-lifting from O(n 3 log n)toO(n2 log n), where n is the size of the program. Since a lambda-lifter can output...

  19. A Practical Approach To Lift-Off

    Science.gov (United States)

    Jones, Susan K.; Chapman, Richard C.; Pavelchek, Edward K.

    1987-08-01

    Lift-off technology provides an alternate metal patterning technology to that of subtractive etching. In this raper, we describe an image reversal process which provides a practical means for reliably producing resist stencils which are required for successful lift-off in a 2.0 μm metal pitch CMOS process, as well as for experimental submicron processing. Experimental data and PROSIM simulations are presented to show the effects of patterning exposure dose, flood exposure dose, develop time, and focus parameters on resist linewidths as well as for control of resist retrograde (undercut) sidewall angles. Deposition and subsequent lift-off of Al/Cu alloys and sandwich metallizations is demonstrated. Because the image reversal process enables pattern definition at the top of the resist film, it is demonstrated that thicker resist films can be used to produce finer resolution of lift-off stencils over topography than would have been expected without resorting to multilayer resist structures.

  20. Direct numerical simulation of particle-laden turbulent channel flows with two- and four-way coupling effects: budgets of Reynolds stress and streamwise enstrophy

    International Nuclear Information System (INIS)

    Dritselis, Chris D

    2016-01-01

    The budgets of the Reynolds stress and streamwise enstrophy are evaluated through direct numerical simulations for the turbulent particle-laden flow in a vertical channel with momentum exchange between the two phases. The influence of the dispersed particles on the budgets is examined through a comparison of the particle-free and the particle-laden cases at the same Reynolds number of Re b = 5600 based on the bulk fluid velocity and the distance between the channel walls. Results are obtained for particle ensembles with four response times in simulations with and without streamwise gravity and inter-particle collisions at average mass (volume) fractions of 0.2 (2.7 × 10 −5 ) and 0.5 (6.8 × 10 −5 ). The particle feedback force on the flow of the carrier phase is modeled by a point-force approximation (PSIC-method). It is shown that all the terms in the budgets of the Reynolds stress components are decreased in the presence of particles. The level of reduction depends on the particle response time and it is higher under the effects of gravity and inter-particle collisions. A considerable reduction in all the terms of the streamwise enstrophy budget is also observed. In particular, all production mechanisms, and mainly vortex stretching, are inhibited in the particulate flows and thus the production of streamwise vorticity is significantly damped. A further insight into the direct particle effects on the fluid turbulence is provided by analyzing in detail the fluid–fluid, fluid–particle and particle–particle correlations, and the spectra of the fluid–particle energy exchange rate. The present results indicate that the turbulence production, dissipation and pressure–strain term are generally large quantities, but their summation is relatively small and comparable to the fluid–particle direct energy exchange rate. Consequently, the particle contribution can potentially increase or decrease the fluctuating fluid velocities and eventually control the

  1. Cost Benefit Analysis of Boat Lifts

    Science.gov (United States)

    2014-09-01

    associated with commercial boat lifts were obtained through a market survey based on products advertised for sale to the general public. The information...from the market survey and knowledge of specific boat maintenance items susceptible to cost reduction using a boat lift were then compared to identify...transferred to the Boat Inventory Manager ( BIM ). Custodians are responsible for maintaining boats and small craft in good working order at all times

  2. Characterization of Oscillatory Lift in MFC Airfoils

    OpenAIRE

    Lang Jr, Joseph Reagle

    2014-01-01

    The purpose of this research is to characterize the response of an airfoil with an oscillatory morphing, Macro-fiber composite (MFC) trailing edge. Correlation of the airfoil lift with the oscillatory input is presented. Modal analysis of the test airfoil and apparatus is used to determine the frequency response function. The effects of static MFC inputs on the FRF are presented and compared to the unactuated airfoil. The transfer function is then used to determine the lift component du...

  3. Visual perception of fatigued lifting actions.

    Science.gov (United States)

    Fischer, Steven L; Albert, Wayne J; McGarry, Tim

    2012-12-01

    Fatigue-related changes in lifting kinematics may expose workers to undue injury risks. Early detection of accumulating fatigue offers the prospect of intervention strategies to mitigate such fatigue-related risks. In a first step towards this objective, this study investigated whether fatigue detection was accessible to visual perception and, if so, what was the key visual information required for successful fatigue discrimination. Eighteen participants were tasked with identifying fatigued lifts when viewing 24 trials presented using both video and point-light representations. Each trial comprised a pair of lifting actions containing a fresh and a fatigued lift from the same individual presented in counter-balanced sequence. Confidence intervals demonstrated that the frequency of correct responses for both sexes exceeded chance expectations (50%) for both video (68%±12%) and point-light representations (67%±10%), demonstrating that fatigued lifting kinematics are open to visual perception. There were no significant differences between sexes or viewing condition, the latter result indicating kinematic dynamics as providing sufficient information for successful fatigue discrimination. Moreover, results from single viewer investigation reported fatigue detection (75%) from point-light information describing only the kinematics of the box lifted. These preliminary findings may have important workplace applications if fatigue discrimination rates can be improved upon through future research. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Metabolic Responses to Weight Lifting

    Directory of Open Access Journals (Sweden)

    Arnold Nelson

    2017-04-01

    Full Text Available Editor's Note, The ability to lift heavy loads while performing multiple repetitions is not only highly correlated with muscle mass or the total number actomyosin interactions, but also metabolic functions that includes substrate concentrations and by-product removal.  Muscles use adenosine triphosphate (ATP in at least three locations during exercise; to run the actomyosin interaction, operate sarcoplasmic reticulum calcium pumps, and operate sarcolemma sodium and potassium pumps.  Weight lifting sessions are considered to be an intermittent activity that includes only a few second bursts of high force and/or velocity movements followed by rest periods of up to several minutes. Therefore, the anaerobic pathways such as the phosphagen and glycolytic systems are the initial pathways to respond due in part to the ability to match the increased rates of ATP depletion by increasing ATP production. After the initial resting ATP stores are used up, the phosphagen system starts contributing to ATP replenishment.  This system consists of reactions from the creatine kinase (CK pathway and the adenylate kinase (AK pathway.  However, the CK pathway can only work at max capacity for a short period for resting phosphocreatine (PCr concentrations are only about 4-6 times the amount of resting ATP stores.  Once the PCr concentrations are depleted, the AK reaction will begin by using two adenosine diphosphate (ADP to form one ATP and one adenosine monophosphate (AMP. Although ATP is produced in this pathway, this production of ATP does coincide with an increased concentration of AMP. This is problematic because increased AMP levels will in turn stimulate the adenylate deaminase reaction, which will produce ammonia (NH3. This conversion of AMP into NH3 will result in the muscle cell having a net loss of total adenine nucleotides available to resynthesize ATP.  Glycolysis is the next reaction in line, which increases its role in ATP replenishment as PCr

  5. Heavy Lift for Exploration: Options and Utilization

    Science.gov (United States)

    Creech, Steve; Sumrall, Phil

    2010-01-01

    Every study of exploration capabilities since the Apollo Program has recommended the renewal of a heavy lift launch capability for the United States. NASA is aggressively pursuing that capability. This paper will discuss several aspects of that effort and the potential uses for that heavy lift capability. The need for heavy lift was cited most recent in the findings of the Review of U.S. Human Space Flight Plans Committee. Combined with considerations of launch availability and on-orbit operations, the Committee finds that exploration will benefit from the availability of a heavy-lift vehicle, the report said. In addition, heavy lift would enable the launching of large scientific observatories and more capable deep-space missions. It may also provide benefit in national security applications. The most recent focus of NASA s heavy lift effort is the Ares V cargo launch vehicle, which is part of the Constellation Program architecture for human exploration beyond low Earth orbit (LEO). The most recent point-of-departure configuration of the Ares V was approved during the Lunar Capabilities concept Review (LCCR) in 2008. The Ares V first stage propulsion system consists of a core stage powered by six commercial liquid hydrogen/liquid oxygen (LH2/LOX) RS-68 engines, flanked by two 5.5-segment solid rocket boosters (SRBs) based on the 5-segment Ares I first stage. The boosters use the same Polybutadiene Acrylonitrile (PBAN) propellant as the Space Shuttle. Atop the core stage is the Earth departure stage (EDS), powered by a single J-2X upper stage engine based on the Ares I upper stage engine. The 33-foot-diameter payload shroud can enclose a lunar lander, scientific instruments, or other payloads. Since LCCR, NASA has continued to refine the design through several successive internal design cycles. In addition, NASA has worked to quantify the broad national consensus for heavy lift in ways that, to the extent possible, meet the needs of the user community.

  6. Numerical Study of Transition of an Annular Lift Fan Aircraft

    OpenAIRE

    Yun Jiang; Bo Zhang

    2016-01-01

    The present study aimed at studying the transition of annular lift fan aircraft through computational fluid dynamics (CFD) simulations. The oscillations of lift and drag, the optimization for the figure of merit, and the characteristics of drag, yawing, rolling and pitching moments in transition are studied. The results show that a two-stage upper and lower fan lift system can generate oscillations of lift and drag in transition, while a single-stage inner and outer fan lift system can elimin...

  7. A Comparison of Thermal Models for Temperature Profiles in Gas-Lift Wells

    Directory of Open Access Journals (Sweden)

    Langfeng Mu

    2018-02-01

    Full Text Available Gas lift is a simple, reliable artificial lift method which is frequently used in offshore oil field developments. In order to enhance the efficiency of production by gas lift, it is vital to exactly predict the distribution of temperature-field for fluid within the wellbore. A new mechanistic model is developed for computing flowing fluid temperature profiles in both conduits simultaneously for a continuous-flow gas-lift operation. This model assumes steady heat transfer in the formation, as well as steady heat transfer in the conduits. A micro-units discrete from the wellbore, whose heat transfer process is analyzed and whose heat transfer equation is set up according to the law of conservation of energy. A simplified algebraic solution to our model is conducted to analyze the temperature profile. Sensitivity analysis was conducted with the new model. The results indicate that mass flow rate of oil and the tubing overall heat transfer coefficient are the main factors that influence the temperature distribution inside the tubing and that the mass flow rate of oil is the main factor affecting temperature distribution in the annulus. Finally, the new model was tested in three various wells and compared with other models. The results showed that the new model is more accurate and provides significant references for temperature prediction in gas lift well.

  8. Thread-Lift Sutures : Still in the Lift? A Systematic Review of the Literature

    NARCIS (Netherlands)

    Gulbitti, Haydar Aslan; Colebunders, Britt; Pirayesh, Ali; Bertossi, Dario; van der Lei, Berend

    Background: In 2006, Villa et al. published a review article concerning the use of thread-lift sutures and concluded that the technique was still in its infancy but had great potential to become a useful and effective procedure for nonsurgical lifting of sagged facial tissues. As 11 years have

  9. Thread-Lift Sutures : Still in the Lift? A Systematic Review of the Literature

    NARCIS (Netherlands)

    Gülbitti, Haydar Aslan; Colebunders, Britt; Pirayesh, Ali; Bertossi, Dario; van der Lei, Berend

    2018-01-01

    BACKGROUND: In 2006, Villa et al. published a review article concerning the use of thread-lift sutures and concluded that the technique was still in its infancy but had great potential to become a useful and effective procedure for nonsurgical lifting of sagged facial tissues. As 11 years have

  10. Effect of training and lifting equipment for preventing back pain in lifting and handling: systematic review

    NARCIS (Netherlands)

    Martimo, Kari-Pekka; Verbeek, Jos; Karppinen, Jaro; Furlan, Andrea D.; Takala, Esa-Pekka; Kuijer, P. Paul F. M.; Jauhiainen, Merja; Viikari-Juntura, Eira

    2008-01-01

    To determine whether advice and training on working techniques and lifting equipment prevent back pain in jobs that involve heavy lifting. Medline, Embase, CENTRAL, Cochrane Back Group's specialised register, CINAHL, Nioshtic, CISdoc, Science Citation Index, and PsychLIT were searched up to

  11. 77 FR 20558 - Federal Motor Vehicle Safety Standards; Platform Lifts for Motor Vehicles; Platform Lift...

    Science.gov (United States)

    2012-04-05

    ... unrelated to the barrier's safety. Lift-U also questioned the agency's statement that it could be difficult... DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration 49 CFR Part 571 [Docket No. NHTSA-2012-0039] RIN 2127-AJ93 Federal Motor Vehicle Safety Standards; Platform Lifts for...

  12. Flow Field Characteristics and Lift Changing Mechanism for Half-Rotating Wing in Hovering Flight

    Science.gov (United States)

    Li, Q.; Wang, X. Y.; Qiu, H.; Li, C. M.; Qiu, Z. Z.

    2017-12-01

    Half-rotating wing (HRW) is a new similar-flapping wing system based on half-rotating mechanism which could perform rotating-type flapping instead of oscillating-type flapping. The characteristics of flow field and lift changing mechanism for HRW in hovering flight are important theoretical basis to improve the flight capability of HRW aircraft. The driving mechanism and work process of HRW were firstly introduced in this paper. Aerodynamic simulation model of HRW in hovering flight was established and solved using XFlow software, by which lift changing rule of HRW was drawn from the simulation solution. On the other hand, the development and shedding of the distal vortex throughout one stroke would lead to the changes of the lift force. Based on analyzing distribution characteristics of vorticity, velocity and pressure around wing blade, the main features of the flow field for HRW were further given. The distal attached vortex led to the increase of the lift force, which would gradually shed into the wake with a decline of lift in the later downstroke. The wake ring directed by the distal end of the blade would generate the downward accelerating airflow which produced the upward anti-impulse to HRW. The research results mentioned above illustrated that the behavior characteristics of vortex formed in flow field were main cause of lift changing for HRW.

  13. Research on the aerodynamic characteristics of a lift drag hybrid vertical axis wind turbine

    Directory of Open Access Journals (Sweden)

    Xiaojing Sun

    2016-01-01

    Full Text Available Compared with a drag-type vertical axis wind turbines, one of the greatest advantages for a lift-type vertical axis wind turbines is its higher power coefficient (Cp. However, the lift-type vertical axis wind turbines is not a self-starting turbine as its starting torque is very low. In order to combine the advantage of both the drag-type and the lift-type vertical axis wind turbines, a lift drag hybrid vertical axis wind turbines was designed in this article and its aerodynamics and starting performance was studied in detail with the aid of computational fluid dynamics simulations. Numerical results indicate that the power coefficient of this lift drag hybrid vertical axis wind turbines declines when the distance between its drag-type blades and the center of rotation of the turbine rotor increases, whereas its starting torque can be significantly improved. Studies also show that unlike the lift-type vertical axis wind turbines, this lift drag hybrid-type vertical axis wind turbines could be able to solve the problem of low start-up torque. However, the installation position of the drag blade is very important. If the drag blade is mounted very close to the spindle, the starting torque of the lift drag hybrid-type vertical axis wind turbines may not be improved at all. In addition, it has been found that the power coefficient of the studied vertical axis wind turbines is not as good as expected and possible reasons have been provided in this article after the pressure distribution along the surfaces of the airfoil-shaped blades of the hybrid turbine was analyzed.

  14. CERN takes off at Lift11

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    CERN was especially featured at the Lift11 conference, held in Geneva early this month. Tara Shears delivered a keynote speech at the event, while Paul Oortman Gerlings (DGS-SEE) and Erik van der Bij (BE-CO) – winners of the Bulletin’s Lift11 competition – organised the CERN workshop.   Paul Oortman Gerlings takes questions at CERN's Lift11 workshop. Lift11 was an opportunity for CERN to reach today’s innovators and developers. “The event was filled with people eager to learn new ideas, who were not afraid to ask questions,” says Tara Shears, physicist from the LHCb Collaboration who presented an update on the status of the LHC. “People were amazed by what goes on inside CERN, by our science, our facilities – even by the way we carry out our day-to-day work. It is a branch of fundamental research that really seems to inspire everyone.” A small Lift11 group had the chance to take a tour of CERN, ...

  15. Win a lift to the future!

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    The Communication Group is organising a competition offering people at CERN the chance to submit their ideas and win a ticket to the Lift10 Conference, which will be held in Geneva from 5 to7 May.   Lift is a community of technology "pioneers", created in 2006. It now involves more than 4,000 people from over 60 countries, who meet regularly in Europe and in Asia to explore the social implications of new technologies and the major shifts ahead. CERN is one of the academic partners of the next Lift conference, whose theme is "Connected people”. For this occasion, 10 free tickets to the conference will be awarded to the "CERNois" who come up with the best answers to the question: “How would you contribute to Lift10?” Those taking part in the competition can choose from among the following categories: - run workshop(s); - cover the conference on a blog; - coordinate a discussion during the breaks; - organize a lift@home ...

  16. TMI-2 reactor vessel plenum final lift

    International Nuclear Information System (INIS)

    Wilson, D.C.

    1986-01-01

    Removal of the plenum assembly from the TMI-2 reactor vessel was necessary to gain access to the core region for defueling. The plenum was lifted from the reactor vessel by the polar crane using three specially designed pendant assemblies. It was then transferred in air to the flooded deep end of the refueling canal and lowered onto a storage stand where it will remain throughout the defueling effort. The lift and transfer were successfully accomplished on May 15, 1985 in just under three hours by a lift team located in a shielded area within the reactor building. The success of the program is attributed to extensive mockup and training activities plus thorough preparations to address potential problems. 54 refs

  17. Quadratic Interpolation and Linear Lifting Design

    Directory of Open Access Journals (Sweden)

    Joel Solé

    2007-03-01

    Full Text Available A quadratic image interpolation method is stated. The formulation is connected to the optimization of lifting steps. This relation triggers the exploration of several interpolation possibilities within the same context, which uses the theory of convex optimization to minimize quadratic functions with linear constraints. The methods consider possible knowledge available from a given application. A set of linear equality constraints that relate wavelet bases and coefficients with the underlying signal is introduced in the formulation. As a consequence, the formulation turns out to be adequate for the design of lifting steps. The resulting steps are related to the prediction minimizing the detail signal energy and to the update minimizing the l2-norm of the approximation signal gradient. Results are reported for the interpolation methods in terms of PSNR and also, coding results are given for the new update lifting steps.

  18. Characterization of graphite dust produced by pneumatic lift

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Ke [Guangdong Provincial Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong (China); Peng, Wei; Liu, Bing [Institute of Nuclear and New Energy Technology of Tsinghua University, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 100084 (China); Kang, Feiyu [Guangdong Provincial Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong (China); Yang, Xiaoyong; Li, Weihua [Institute of Nuclear and New Energy Technology of Tsinghua University, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 100084 (China); Yu, Suyuan, E-mail: suyuan@tsinghua.edu.cn [Center for Combustion Energy, The Key Laboratory for Thermal Science and Power Engineering, Ministry of Educations, Tsinghua University, Beijing 100084 (China)

    2016-08-15

    Highlights: • Generation of graphite dust by pneumatic lift. • Determination of morphology and particle size distribution of graphite dust. • The size of graphite dust in this study is compared to AVR and THTR-300 results. • Graphite dust originates from both filler and binder of the matrix graphite. - Abstract: Graphite dust is an important safety concern of high-temperature gas-cooled reactor (HTR). The graphite dust could adsorb fission products, and the radioactive dust is transported by the coolant gas and deposited on the surface of the primary loop. The simulation of coagulation, aggregation, deposition, and resuspension behavior of graphite dust requires parameters such as particle size distribution and particle shape, but currently very limited data on graphite dust is available. The only data we have are from AVR and THTR-300, however, the AVR result is likely to be prejudiced by the oil ingress. In pebble-bed HTR, graphite dust is generally produced by mechanical abrasion, in particular, by the abrasion of graphite pebbles in the lifting pipe of the fuel handling system. Here we demonstrate the generation and characterization of graphite dust that were produced by pneumatic lift. This graphite dust could substitute the real dust in HTR for characterization. The dust, exhibiting a lamellar morphology, showed a number-weighted average particle size of 2.38 μm and a volume-weighted average size of 14.62 μm. These two sizes were larger than the AVR and THTR results. The discrepancy is possibly due to the irradiation effect and prejudice caused by the oil ingress accident. It is also confirmed by the Raman spectrum that both the filler particle and binder contribute to the dust generation.

  19. Lift mechanics of downhill skiing and snowboarding.

    Science.gov (United States)

    Wu, Qianhong; Igci, Yesim; Andreopoulos, Yiannis; Weinbaum, Sheldon

    2006-06-01

    This study is conducted to develop a simplified mathematical model to describe the lift mechanics of downhill skiing and snowboarding, where the lift contributions due to both the transiently trapped air and the compressed solid phase (snow crystals) are determined. To our knowledge, this is the first time that anyone has attempted to realistically estimate the relative contribution of the transiently trapped air to the total lift in skiing and snowboarding. The model uses Shimizu's empirical relation to predict the local variation in Darcy permeability due to the compression of the solid phase. The forces and moments on the skier or snowboarder are used to predict the angle of attack of the planing surface, the penetration depth at the leading edge, and the shift in the center of pressure for two typical snow types, fresh and wind-packed snow. We present numerical solutions for snowboarding and asymptotic analytic solutions for skiing for the case where there are no edging or turning maneuvers. The force and moment balance are then used to develop a theory for control and stability in response to changes in the center of mass as the individual shifts his/her weight. Our model predicts that for fine-grained, windpacked snow that when the velocity (U) of the snowboarder or skier is 20 m.s, approximately 50% of the total lift force is generated by the trapped air for snowboarding and 40% for skiing. For highly permeable fresh powder snow, the lift contribution from the pore air pressure drops substantially. This paper develops a new theoretical framework for analyzing the lift mechanics and stability of skis and snowboards that could have important applications in future ski and snowboard design.

  20. Testing lifting systems in nuclear facilities

    International Nuclear Information System (INIS)

    Kling, H.; Laug, R.

    1984-01-01

    Lifting systems in nuclear facilities must be inspected at regular intervals after having undergone their first acceptance test. These inspections are frequently carried out by service firms which not only employ the skilled personnel required for such jobs but also make available the necessary test equipment. The inspections in particular include a number of sophisticated load tests for which test load systems have been developed to allow lifting systems to be tested so that reactor specific boundary conditions are taken into account. In view of the large number of facilities to be inspected, the test load system is a modular system. (orig.) [de

  1. Asymmetric Gepner models II. Heterotic weight lifting

    Energy Technology Data Exchange (ETDEWEB)

    Gato-Rivera, B. [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); Schellekens, A.N., E-mail: t58@nikhef.n [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); IMAPP, Radboud Universiteit, Nijmegen (Netherlands)

    2011-05-21

    A systematic study of 'lifted' Gepner models is presented. Lifted Gepner models are obtained from standard Gepner models by replacing one of the N=2 building blocks and the E{sub 8} factor by a modular isomorphic N=0 model on the bosonic side of the heterotic string. The main result is that after this change three family models occur abundantly, in sharp contrast to ordinary Gepner models. In particular, more than 250 new and unrelated moduli spaces of three family models are identified. We discuss the occurrence of fractionally charged particles in these spectra.

  2. Soccer ball lift coefficients via trajectory analysis

    International Nuclear Information System (INIS)

    Goff, John Eric; Carre, Matt J

    2010-01-01

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.

  3. Soccer ball lift coefficients via trajectory analysis

    Energy Technology Data Exchange (ETDEWEB)

    Goff, John Eric [Department of Physics, Lynchburg College, Lynchburg, VA 24501 (United States); Carre, Matt J, E-mail: goff@lynchburg.ed [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2010-07-15

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.

  4. Asymmetric Gepner models II. Heterotic weight lifting

    International Nuclear Information System (INIS)

    Gato-Rivera, B.; Schellekens, A.N.

    2011-01-01

    A systematic study of 'lifted' Gepner models is presented. Lifted Gepner models are obtained from standard Gepner models by replacing one of the N=2 building blocks and the E 8 factor by a modular isomorphic N=0 model on the bosonic side of the heterotic string. The main result is that after this change three family models occur abundantly, in sharp contrast to ordinary Gepner models. In particular, more than 250 new and unrelated moduli spaces of three family models are identified. We discuss the occurrence of fractionally charged particles in these spectra.

  5. Active Control of Flow Separation on a High-Lift System with Slotted Flap at High Reynolds Number

    Science.gov (United States)

    Khodadoust, Abdollah; Washburn, Anthony

    2007-01-01

    The NASA Energy Efficient Transport (EET) airfoil was tested at NASA Langley's Low- Turbulence Pressure Tunnel (LTPT) to assess the effectiveness of distributed Active Flow Control (AFC) concepts on a high-lift system at flight scale Reynolds numbers for a medium-sized transport. The test results indicate presence of strong Reynolds number effects on the high-lift system with the AFC operational, implying the importance of flight-scale testing for implementation of such systems during design of future flight vehicles with AFC. This paper describes the wind tunnel test results obtained at the LTPT for the EET high-lift system for various AFC concepts examined on this airfoil.

  6. Characterizing the Severe Turbulence Environments Associated with Commercial Aviation Accidents. Part 2; Hydrostatic Mesobeta Scale Numerical Simulations of Supergradient Wind Flow and Streamwise Ageostrophic Frontogenesis

    Science.gov (United States)

    Kaplan, Michael L.; Huffman, Allan W.; Lux, Kevin M.; Cetola, Jeffrey D.; Charney, Joseph J.; Riordan, Allen J.; Lin, Yuh-Lang; Waight, Kenneth T., III; Proctor, Fred (Technical Monitor)

    2003-01-01

    Simulation experiments reveal key processes that organize a hydrostatic environment conducive to severe turbulence. The paradigm requires juxtaposition of the entrance region of a curved jet stream, which is highly subgeostrophic, with the entrance region of a straight jet stream, which is highly supergeostrophic. The wind and mass fields become misphased as the entrance regions converge resulting in the significant spatial variation of inertial forcing, centripetal forcing, and along- and cross-stream pressure gradient forcing over a mesobeta scale region. This results in frontogenesis and the along-stream divergence of cyclonic and convergence of cyclonic ageostrophic vertical vorticity. The centripetally forced mesoscale front becomes the locus of large gradients of ageostrophic vertical vorticity along an overturning isentrope. This region becomes favorable for streamwise vorticity gradient formation enhancing the environment for organization of horizontal vortex tubes in the presence of buoyant forcing.

  7. Lifting devices in nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    The regulation applies to lifts, cranes, winches, rail trolleys, load pick-up equipment and fuel charging machines for LWR reactors, as far as these are employed in plants for the production or fission of nuclear fuels or for the reprocessing of spent nuclear fuels or for the storage or other uses of nuclear fuels. (orig.) 891 HP [de

  8. Leading-Edge Vortex lifts swifts

    NARCIS (Netherlands)

    Videler, JJ; Stamhuis, EJ; Povel, GDE

    2004-01-01

    The current understanding of how birds fly must be revised, because birds use their hand-wings in an unconventional way to generate lift and drag. Physical models of a common swift wing in gliding posture with a 60degrees sweep of the sharp hand-wing leading edge were tested in a water tunnel.

  9. Lifts of matroid representations over partial fields

    NARCIS (Netherlands)

    Pendavingh, R.A.; Zwam, van S.H.M.

    2010-01-01

    There exist several theorems which state that when a matroid is representable over distinct fields F1,...,Fk , it is also representable over other fields. We prove a theorem, the Lift Theorem, that implies many of these results. First, parts of Whittle's characterization of representations of

  10. Lifts of projective congruence groups, II

    DEFF Research Database (Denmark)

    Kiming, Ian

    2014-01-01

    We continue and complete our previous paper ``Lifts of projective congruence groups'' concerning the question of whether there exist noncongruence subgroups of  that are projectively equivalent to one of the groups  or . A complete answer to this question is obtained: In case of  such noncongruence...

  11. Measuring Lift with the Wright Airfoils

    Science.gov (United States)

    Heavers, Richard M.; Soleymanloo, Arianne

    2011-01-01

    In this laboratory or demonstration exercise, we mount a small airfoil with its long axis vertical at one end of a nearly frictionless rotating platform. Air from a leaf blower produces a sidewise lift force L on the airfoil and a drag force D in the direction of the air flow (Fig. 1). The rotating platform is kept in equilibrium by adding weights…

  12. The Revolutionary Vertical Lift Technology (RVLT) Project

    Science.gov (United States)

    Yamauchi, Gloria K.

    2018-01-01

    The Revolutionary Vertical Lift Technology (RVLT) Project is one of six projects in the Advanced Air Vehicles Program (AAVP) of the NASA Aeronautics Research Mission Directorate. The overarching goal of the RVLT Project is to develop and validate tools, technologies, and concepts to overcome key barriers for vertical lift vehicles. The project vision is to enable the next generation of vertical lift vehicles with aggressive goals for efficiency, noise, and emissions, to expand current capabilities and develop new commercial markets. The RVLT Project invests in technologies that support conventional, non-conventional, and emerging vertical-lift aircraft in the very light to heavy vehicle classes. Research areas include acoustic, aeromechanics, drive systems, engines, icing, hybrid-electric systems, impact dynamics, experimental techniques, computational methods, and conceptual design. The project research is executed at NASA Ames, Glenn, and Langley Research Centers; the research extensively leverages partnerships with the US Army, the Federal Aviation Administration, industry, and academia. The primary facilities used by the project for testing of vertical-lift technologies include the 14- by 22-Ft Wind Tunnel, Icing Research Tunnel, National Full-Scale Aerodynamics Complex, 7- by 10-Ft Wind Tunnel, Rotor Test Cell, Landing and Impact Research facility, Compressor Test Facility, Drive System Test Facilities, Transonic Turbine Blade Cascade Facility, Vertical Motion Simulator, Mobile Acoustic Facility, Exterior Effects Synthesis and Simulation Lab, and the NASA Advanced Supercomputing Complex. To learn more about the RVLT Project, please stop by booth #1004 or visit their website at https://www.nasa.gov/aeroresearch/programs/aavp/rvlt.

  13. Thread-Lift Sutures: Still in the Lift? A Systematic Review of the Literature.

    Science.gov (United States)

    Gülbitti, Haydar Aslan; Colebunders, Britt; Pirayesh, Ali; Bertossi, Dario; van der Lei, Berend

    2018-03-01

    In 2006, Villa et al. published a review article concerning the use of thread-lift sutures and concluded that the technique was still in its infancy but had great potential to become a useful and effective procedure for nonsurgical lifting of sagged facial tissues. As 11 years have passed, the authors now performed again a systematic review to determine the real scientific current state of the art on the use of thread-lift sutures. A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed database and using the Medical Subject Headings search term "Rhytidoplasty." "Rhytidoplasty" and the following entry terms were included by this Medical Subject Headings term: "facelift," "facelifts," "face Lift," "Face Lifts," "Lift," "Face," "Lifts," "Platysmotomy," "Platysmotomies," "Rhytidectomy," "Rhytidectomies," "Platysmaplasty," "and "Platysmaplasties." The Medical Subject Headings term "Rhytidoplasty" was combined with the following search terms: "Barbed suture," "Thread lift," "APTOS," "Suture suspension," "Percutaneous," and "Silhouette suture." RefWorks was used to filter duplicates. Three of the authors (H.A.G., B.C., and B.L.) performed the search independently. The initial search with all search terms resulted in 188 articles. After filtering the duplicates and the articles about open procedures, a total of 41 articles remained. Of these, the review articles, case reports, and letters to the editor were subsequently excluded, as were reports dealing with nonbarbed sutures, such as Vicryl and Prolene with Gore-Tex. This resulted in a total of 12 articles, seven additional articles since the five articles reviewed by Villa et al. The authors' review demonstrated that, within the past decade, little or no substantial evidence has been added to the peer-reviewed literature to support or sustain the promising statement about thread-lift sutures as made by Villa et al. in 2006 in terms of

  14. Mannesmann Demag crawler cranes give plants a big lift

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Preassembly of large reactor components reduces construction costs, but creates the need for cranes with larger lifting capacities. A German company is extending its range with a new crawler crane which will lift up to 1600t. (author)

  15. Effect of hydrogen addition on autoignited methane lifted flames

    KAUST Repository

    Choin, Byung Chul; Chung, Suk-Ho

    2012-01-01

    Autoignited lifted flames in laminar jets with hydrogen-enriched methane fuels have been investigated experimentally in heated coflow air. The results showed that the autoignited lifted flame of the methane/hydrogen mixture, which had an initial

  16. Lifting Safety: Tips To Help Prevent Back Injuries

    Science.gov (United States)

    ... Prevent Back Injuries Lifting Safety: Tips to Help Prevent Back Injuries Share Print Back injuries are common problems at work, home, and play. They can be caused by accidents or improper lifting technique. Below are tips to ...

  17. Analysis of lifting beam and redesigned lifting lugs for 241-AZ-01A decant pump

    International Nuclear Information System (INIS)

    Coverdell, B.L.

    1994-01-01

    This supporting document details calculations for the proper design of a lifting beam and redesigned lifting lugs for the 241AZO1A decant pump. This design is in accordance with Standard Architectural-Civil Design Criteria, Design Loads for Facilities (DOE-RL 1989) and is safety class three. The design and fabrication is in accordance with American Institute of Steel Construction, Manual of Steel Construction, (AISC, 1989) and the Hanford Hoisting and Rigging Manual (DOE-RL 1993)

  18. CFD Study of a New Annular Lift Fan Configuration with High Lift Efficiency

    Directory of Open Access Journals (Sweden)

    Yun Jiang

    2017-03-01

    Full Text Available A new annular lift fan configuration that has very high lift efficiency is explored by using a numerical scheme. The inlet lip radius and diffuser angle are maximized by semicircle duct walls and the location of the lift fan is moved from the throat to the diffuser area to maximize the diffusion effect of the ducted fan. The improved lift fan achieves the figure of merit of 0.772 and the power loading of 9.03 lbs/hp without ground effect, very close to the theoretical limit. Under the ground effect, the figure of merit reaches 0.822 with the power loading of 9.62 lbs/hp. The improved lift efficiency deteriorates the transition characteristics with higher momentum drag and pitching moment. However, with the aid of jet thrusts directly providing part of the lift during transition, the peak of momentum drag and pitching moment can be lowered. A total thrust to weight ratio of 0.7 is enough for all of the requirements in transition and in hover and for the maximum speed of 0.75 Mach in cruise flight.

  19. The Design of Wheelchair Lifting Mechanism and Control System

    Institute of Scientific and Technical Information of China (English)

    ZHAO Cong; WANG Zheng-xing; JIANG Shi-hong; ZHANG Li; LIU Zheng-yu

    2014-01-01

    In order to achieve a wheelchair lift function, this paper designs a tri-scissors mechanism. Through the so-called H-type transmission and L-type swing rod, the three scissors mechanisms lift in the same rate with only one liner motor while ensuring the stability of the lift. Finite element analysis in ANSYS is performed to verify the material strength. The control system with Sunplus SCM achieves the voice control of wheelchair walking and lifting.

  20. 21 CFR 880.5500 - AC-powered patient lift.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5500 AC-powered patient lift. (a) Identification. An AC-powered lift is an electrically powered device either fixed or mobile, used to lift and transport patients in the horizontal or other...

  1. A Computation Fluid Dynamic Model for Gas Lift Process Simulation in a Vertical Oil Well

    Directory of Open Access Journals (Sweden)

    Kadivar Arash

    2017-03-01

    Full Text Available Continuous gas-lift in a typical oil well was simulated using computational fluid dynamic (CFD technique. A multi fluid model based on the momentum transfer between liquid and gas bubbles was employed to simulate two-phase flow in a vertical pipe. The accuracy of the model was investigated through comparison of numerical predictions with experimental data. The model then was used to study the dynamic behaviour of the two-phase flow around injection point in details. The predictions by the model were compared with other empirical correlations, as well. To obtain an optimum condition of gas-lift, the influence of the effective parameters including the quantity of injected gas, tubing diameter and bubble size distribution were investigated. The results revealed that increasing tubing diameter, the injected gas rate and decreasing bubble diameter improve gas-lift performance.

  2. Distribution

    Science.gov (United States)

    John R. Jones

    1985-01-01

    Quaking aspen is the most widely distributed native North American tree species (Little 1971, Sargent 1890). It grows in a great diversity of regions, environments, and communities (Harshberger 1911). Only one deciduous tree species in the world, the closely related Eurasian aspen (Populus tremula), has a wider range (Weigle and Frothingham 1911)....

  3. Lifting CERN entrepreneurs to new heights

    CERN Multimedia

    William Rode

    2014-01-01

    How can an international research institution help employees who wish to leave their comfort zone for the risky endeavour of starting a company? CERN encourages the creation of companies as a way of disseminating technology developed here. But what else can be done to foster these initiatives?   William Rode, a technical student in CERN’s Knowledge Transfer Group, studied spin-off creations in some leading research institutions as part of his Master's thesis in entrepreneurship at the Norwegian University of Science and Technology. William, who was offered a ticket to attend the Lift14 conference in Geneva, shares some insight into how we can support entrepreneurship at CERN: "A while ago I attended the Lift conference in Geneva. The conference explores the business and social implications of technology innovation through talks and workshops, as well as through art and discussion. Innovation is at the core of the conference and is reflected in the open-mindedness of th...

  4. Leading-edge vortex lifts swifts.

    Science.gov (United States)

    Videler, J J; Stamhuis, E J; Povel, G D E

    2004-12-10

    The current understanding of how birds fly must be revised, because birds use their hand-wings in an unconventional way to generate lift and drag. Physical models of a common swift wing in gliding posture with a 60 degrees sweep of the sharp hand-wing leading edge were tested in a water tunnel. Interactions with the flow were measured quantitatively with digital particle image velocimetry at Reynolds numbers realistic for the gliding flight of a swift between 3750 and 37,500. The results show that gliding swifts can generate stable leading-edge vortices at small (5 degrees to 10 degrees) angles of attack. We suggest that the flow around the arm-wings of most birds can remain conventionally attached, whereas the swept-back hand-wings generate lift with leading-edge vortices.

  5. Eisenhart lift for higher derivative systems

    Energy Technology Data Exchange (ETDEWEB)

    Galajinsky, Anton, E-mail: galajin@tpu.ru; Masterov, Ivan, E-mail: masterov@tpu.ru

    2017-02-10

    The Eisenhart lift provides an elegant geometric description of a dynamical system of second order in terms of null geodesics of the Brinkmann-type metric. In this work, we attempt to generalize the Eisenhart method so as to encompass higher derivative models. The analysis relies upon Ostrogradsky's Hamiltonian. A consistent geometric description seems feasible only for a particular class of potentials. The scheme is exemplified by the Pais–Uhlenbeck oscillator.

  6. Analysis of the Umbrella Roof for lifting

    International Nuclear Information System (INIS)

    Shaaban, A.

    1983-01-01

    In addition to supporting the dead loads and the operational loads, the Umbrella Roof (UR) has two major functions to which it was designed. First is to allow access for repair and removal of any of the TF coils, the upper PF coils and the Vacuum Vessel sections; and second, is to reproduce the exact positioning of the upper PF coils every time the UR is placed over the Tokamac. To provide these functions, the UR is designed to be lifted as one integrated structure to which the upper PF coils are attached. In order to ensure precise positioning of the UR, a redundant system of 13 guide pins were provided on the bottom of the radial beams, and four shear lugs were provided atop the central column. Mating reciprocals with very close tolerance for the guide pins were provided in the tops of the 13 peripheral columns. To meet close tolerances and to accommodate such high redundancy in match points, accurate analysis was necessary by which the center of gravity of the UR can be located and the deflection of all match points can be computed. Also stress analysis of the members of the UR was necessary because when the UR is lifted it is denied the midpoint support over the center column; and also the beams of the UR are not interconnected by moment-capable joints, thus if provisions are not made to support every radial beam, those which are not supported would yield and collapse. In this paper, the lifting schemes proposed for the UR are discussed and the results of the analysis performed for the elected scheme are presented. Also presented is a unique application of the NASTRAN code by which the center of gravity of the UR was located by allowing a refined model of the UR to swing until it came to rest under an arbitrary lift point

  7. Lift of dilogarithm to partition identities

    International Nuclear Information System (INIS)

    Terhoeven, M.

    1992-11-01

    For the whole set of dilogarithm identities found recently using the thermodynamic Bethe-Ansatz for the ADET series of purely elastic scattering theories we give partition identities which involve characters of those conformal field theories which correspond to the UV-limits of the scattering theories. These partition identities in turn allow to derive the dilogarithm identities using modular invariance and a saddle point approximation. We conjecture on possible generalizations of this correspondance, namely, a lift from dilogarithm to partition identities. (orig.)

  8. Neck lift my way: an update.

    Science.gov (United States)

    Feldman, Joel J

    2014-12-01

    The author updates prior descriptions of an approach to the surgical neck lift that aims for a maximum degree of control over the size, shape, and position of every anatomical feature of the neck that is negatively affecting its appearance. A 38-year clinical experience guided the development of the operative tactics that define the strategy. Data collected from a records review of 522 consecutive neck lifts performed during the 10-year period 2004 through 2013 further inform the report. The approach has eight features: (1) nearly routine use of open submental access to all tissue layers of the central neck, including a regimen that curbed the problems that may attend an extensive tissue dissection; (2) management of lax neck skin by lateral excision using a specific postauricular incision, or by using the nonexcisional method of redistribution; (3) open lipectomy for precise removal of excess subcutaneous neck and jawline fat; (4) individualized modifications to subplatysmal fat, perihyoid fascia, and anterior digastric muscles; (5) treatment of large, ptotic, or malpositioned submandibular salivary glands by partial excision using a transcutaneous traction suture; (6) the current version of the corset platysmaplasty, which is used to treat static paramedian platysma muscle bands, and to avoid contour imperfections following subplatysmal maneuvers; (7) an approach that facilitates an isolated neck lift; and (8) durable results. Case examples demonstrate outcomes. Although the updated approach remains relatively complex and invasive, the author believes that the ends justify the means.

  9. Occupational lifting, fetal death and preterm birth

    DEFF Research Database (Denmark)

    Mocevic, Emina; Svendsen, Susanne Wulff; Jørgensen, Kristian Tore

    2014-01-01

    OBJECTIVE: We examined the association between occupational lifting during pregnancy and risk of fetal death and preterm birth using a job exposure matrix (JEM). METHODS: For 68,086 occupationally active women in the Danish National Birth Cohort, interview information on occupational lifting...... the JEM. We used Cox regression models with gestational age as underlying time variable and adjustment for covariates. RESULTS: We observed 2,717 fetal deaths and 3,128 preterm births within the study cohort. No exposure-response relation was observed for fetal death, but for women with a prior fetal...... death, we found a hazard ratio (HR) of 2.87 (95% CI 1.37, 6.01) for stillbirth (fetal death ≥22 completed gestational weeks) among those who lifted >200 kg/day. For preterm birth, we found an exposure-response relation for primigravid women, reaching a HR of 1.43 (95% CI 1.13, 1.80) for total loads >200...

  10. Dynamic response of Hovercraft lift fans

    Science.gov (United States)

    Moran, D. D.

    1981-08-01

    Hovercraft lift fans are subjected to varying back pressure due to wave action and craft motions when these vehicles are operating in a seaway. The oscillatory back pressure causes the fans to perform dynamically, exhibiting a hysteresis type of response and a corresponding degradation in mean performance. Since Hovercraft motions are influenced by variations in lift fan pressure and discharge, it is important to understand completely the nature of the dynamic performance of lift fans in order to completely solve the Hovercraft seakeeping problem. The present study was performed to determine and classify the instabilities encountered in a centrifugal fan operating against time-varying back pressure. A model-scale experiment was developed in which the fan discharge was directed into a flow-measuring device, terminating in a rotating valve which produced an oscillatory back pressure superimposed upon a mean aerodynamic resistance. Pressure and local velocity were measured as functions of time at several locations in the fan volute. The measurements permitted the identification of rotating (or propagating) stall in the impeller. One cell and two cell configurations were classified and the transient condition connecting these two configurations was observed. The mechanisms which lead to rotating stall in a centrifugal compressor are presented and discussed with specific reference to Hovercraft applications.

  11. An auto lifting device to lift manhole cover with ergonomics consideration

    Science.gov (United States)

    Draman, Wan Nur A'tiqah Wan; Majid, D. L.; Ishak, Muhammad Ikman; Rosli, M. U.; Lailina N., M.; Ismail, Ras Izzati

    2017-09-01

    The sewerage and maintenance process of manhole is important to ensure that the underground pipelines and other systems are in good condition. The manhole is covered with manhole cover to prevent people, animals or any objects fall into it. The manhole cover has one pocket which is to lock it and ensure that nobody open it. A questionnaire survey is distributed to the workers at Indah Water Konsortium Sdn Bhd, Kuala Lumpur and interviews are conducted with Indah Water Konsortium (IWK) and Jabatan Perkhidmatan Pembentungan (JPP), Selangor to access the user requirements and needs for an effective manhole cover lifter. Currently, the workers used a T-hook to unlock the heavy manhole cover and lift it. However, this method affected some of the workers because they experienced back, legs, shoulders and arm injuries. The T-hook is also quite heavy and it is difficult to bring anywhere. Based on the result of questionnaire survey, four concepts are designed to create new manhole cover lifter with automated operation. The best concept is finalized by using concept screening and scoring method. The chosen concept is applied pulley chain mechanism and it is selected as the best concept because it is easy and safe to use, low cost maintenance, low time consuming and affordable price. The design of the device is suitable for Malaysian male and secured them from musculoskeletal disorder. The worker's posture is analyzed by using Rapid Upper Limb Analysis (RULA) ergonomics analysis. The stability and strength of the device is analyzed by calculation and Finite Element Analysis (FEA) is used to analyze the screw cylinder.

  12. Masculinity and Lifting Accidents among Danish Ambulance Personnel

    DEFF Research Database (Denmark)

    Hansen, Claus D.; Nielsen, Kent J

    Background Work injuries related to lifting are the most prevalent among ambulance personnel (AP) despite the introduction of ‘assistive technologies’ (AT) that help reduce situations of manual lifting. One third of the AP report using AT only ‘sometimes’ and 10% report having lifted a patient...... alone. Aim This presentation investigates whether failure to use AT is linked to male ambulance workers’ gender identity? Is lifting patients alone a way of performing masculinity for AP’s? Method Data is taken from MARS, a panel study of AP workers in Denmark (n = 1606). Information from questionnaires...... measuring traditional male role norms (MRNI), safety attitudes and safety behavior will be linked to company register information on work injuries categorized as lifting accidents. Logistic regression is used to analyse associations between masculinity, lifting behavior, and lifting accidents. Results...

  13. Study on dynamic lifting characteristics of control rod drive mechanism

    International Nuclear Information System (INIS)

    Shen Xiaoyao

    2012-01-01

    Based on the equations of the electric circuit and the magnetic circuit and analysis of the dynamic lifting process for the control rod drive mechanism (CRDM), coupled magnetic-electric-mechanical equations both for the static status and the dynamic status are derived. The analytical method is utilized to obtain the current and the time when the lift starts. The numerical simulation method of dynamic analysis recommended by ASME Code is utilized to simulate the dynamic lifting process of CRDM, and the dynamic features of the system with different design gaps are studied. Conclusions are drawn as: (1) the lifting-start time increases with the design gap, and the time for the lifting process is longer with larger gaps; (2) the lifting velocity increases with time; (3) the lifting acceleration increases with time, and with smaller gaps, the impact acceleration is larger. (author)

  14. How to lift a box that is too large to fit between the knees

    NARCIS (Netherlands)

    Kingma, I.; Faber, G.S.; van Dieen, J.H.

    2010-01-01

    Many studies compared lifting techniques such as stoop and squat lifting. Results thus far show that when lifting a wide load, high back loads result, irrespective of the lifting technique applied. This study compared four lifting techniques in 11 male subjects lifting wide loads. One of these

  15. Leading-Edge Velocities and Lifted Methane Jet Flame Stability

    Directory of Open Access Journals (Sweden)

    W. Wang

    2010-01-01

    Full Text Available Current interest exists in understanding reaction-zone dynamics and mechanisms with respect to how they counterpropagate against incoming reactants. Images of flame position and flow-field morphology are presented from flame chemiluminescence and particle image velocimetry (PIV measurements. In the present study, PIV experiments were carried out to measure the methane jet lifted-flame flow-field velocities in the vicinity of the flame leading edge. Specifically, velocity fields within the high-temperature zone were examined in detail, which complements previous studies, whose prime focus is the flow-field upstream of the high-temperature boundary. PIV data is used not only to determine the velocities, but, along with chemiluminescence images, to also indicate the approximate location of the reaction zone (further supported by/through the leading-edge flame velocity distributions. The velocity results indirectly support the concept that the flame is anchored primarily through the mechanism of partially premixed flame propagation.

  16. A walker used as a lifting device.

    Science.gov (United States)

    Glimskär, Bo; Hjalmarson, Jenny; Lundberg, Stefan; Larsson, Tore

    2014-05-01

    To develop assistive technology that would help an older person to arise from a kneeling position to a standing one. Developing a prototype, based on an inclusive design and then testing the prototype to verify the approach. The prototype was subsequently tested by a panel of 20 elderly users. These tests were observed and filmed. Participants' experiences of being lifted with the elevation seat were registered with the VIDAR ergonomic assessment system. None of the 20 participants used a walker at that time. In response to a question of whether, assuming they might have to use a walker in the future, they thought that a walker with an elevating seat would be helpful, 18 said that it would. Two of the participants did not believe that they would ever have to use a walker. A simple assistive technology such as a walker equipped with an elevating seat would in many of these cases simplify matters and reduce the distress of people who fall often. In addition, such a device can allow people who fall often to live in their homes longer. For caregivers dealing frequently with people who fall, this assistive device can contribute to decreasing occupational injuries. Development of a lifting device that can help people raise themselves up entirely on their own, or with minimal assistance, would be a revolutionary step for the individual. Lifting devices in use today requires much more extensive assistance from home helpers or others and due to the risk of injuries it is a great value for the helpers that easy to use devices develops. A walker equipped with an elevating seat could even provide a potential for people to stay in their homes longer.

  17. An elevator for lifting and turning pipes

    Energy Technology Data Exchange (ETDEWEB)

    Melnikov, S.P.; Borchenkov, G.I.; Komarov, V.N.; Lebedev, D.A.

    1983-01-01

    An elevator is proposed for lifting and turning pipes, which includes a body and a bushing hinged to it with projections and a shank with a threaded adapter and cams which interact with the projections of the bushing. In order to increase the operational safety of the device through ensuring the capability of eliminating drops in the torque from the shank to the body when raising and extracting drill pipes, the body is equipped with eccentric cams rigidly connected to it, while the shank is equipped with a ring movable connected with it. The eccentric cams are installed between the bushing and the body with the capability of interacting with the shank ring.

  18. Safety mechanism of a lifting machine

    International Nuclear Information System (INIS)

    Blaive, D.; Chopinet, E.

    1985-01-01

    The lifting machine has at least one winch supporting a chain which passes around a chain pulley in a roller block attached to the load. At least one locking mechanism prevents the rotation of the pulley within the block. The locking mechanism can moves between an out-of-operation position and a locking position. A control system includes load sensors associated with the winch sensing the weight of the load acting through the chain. If one part of the chain should break, the load sensors detect this, and the locking mechanism is activated. The invention applies, more particularly, to the handling winches in a fast neutron nuclear power plant [fr

  19. Containment vessel bottom head transport and lifting technique

    International Nuclear Information System (INIS)

    Zheng Donghong; Tian Shiyong; Hu Dequan; Xiao Hongtao

    2013-01-01

    The challengeable transport and lifting techniques and high safety assurance measures are needed for the onsite construction of the AP1000 containment vessel bottom head (CVBH), which is a large component with heavy weight, big size, high center of gravity, and easy to deformation. During transport, the infra structural road foundation is heavily loaded with big turning radius, and the requirement for synchronization of transport vehicles is strict. During lifting, the crane lifting capacities are high, requirement for the lifting and rigging tools is strict, nuclear island being put into place is difficult, and the crane operating foundation is heavily loaded. The transport and lifting techniques and safety assurance measures for CVBH are elaborated in detail, so as to provide a reference for the follow-up transport and lifting of large components of nuclear island. (authors)

  20. Back injury prevention: a lift team success story.

    Science.gov (United States)

    Hefti, Kelly S; Farnham, Richard J; Docken, Lisa; Bentaas, Ruth; Bossman, Sharon; Schaefer, Jill

    2003-06-01

    Work related back injuries among hospital personnel account for high volume, high cost workers' compensation claims. These injuries can be life altering experiences, affecting both the personal and professional lives of injured workers. Lifting must be viewed as a skill involving specialized training and mandated use of mechanical equipment, rather than as a random task performed by numerous health care providers. The use of a lift team specially trained in body mechanics, lifting techniques, and the use of mandated mechanical equipment can significantly affect injury data, financial outcomes, and employee satisfaction. The benefits of a lift team extend beyond the effect on injury and financial outcomes--they can be used for recruitment and retention strategies, and team members serve as mentors to others by demonstrating safe lifting techniques. Ultimately, a lift team helps protect a valuable resource--the health care worker.

  1. Linnainstallatsioonide festival "Lift 11" = Urban installations festival Lift 11 / Margit Aule, Margit Argus ; intervjueerinud Margit Mutso

    Index Scriptorium Estoniae

    Aule, Margit, 1981-

    2012-01-01

    Linnainstallatsioonide festivalist "Lift 11", installatsioonidest. Festivali kuraatorid Margit Argus ja Margit Aule ning kaaskuraatorid Maarin Ektermann ja Ingrid Ruudi pälvisid EK arhitektuuri sihtkapitali 2011. a. arhitektuurialase tegevuse preemia avaliku linnaruumi mitmekesisust märkama, kasutama ning mõtestama ärgitanud ürituse korraldamise eest

  2. Liebherr lifts off with east coast projects

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2004-11-01

    Liebherr is one of the world's leading manufacturers of construction machinery, and is the supplier of technically-innovative user-oriented products and services not only to the oil industry but also to other industries using heavy lifting equipment. The Newfoundland and Labrador offshore oil and gas sector has been a special springboard of success for the company; they have seven offshore cranes working on three installations, and as the White Rose floating production vessel sails to the Grand Banks in 2005, the number will increase to nine. The other cranes are on the Hibernia platform, the Terra Nova FPSO, and the Henry Goodrich drilling rig. Two of the cranes on the Terra Nova FPSO have a lift capacity of 40 tons, while a third crane mounted at the rear of the vessel has a 20 ton capacity. They are capable of performing loading operations in seas as high as three metres. These cranes are powerful, compact and maneuverable, and feature ultra-modern mobile crane technology that satisfies combined road and off-road operating requirements on construction sites of all kinds. 2 photos.

  3. Deep-water subsea lifting operations

    Energy Technology Data Exchange (ETDEWEB)

    Nestegaard, Arne; Boee, Tormod

    2010-07-01

    Significant costs are related to marine operations in the installation phase of deep water subsea field developments. In order to establish safe operational criteria and procedures for the installation, detailed planning is necessary, including numerical modelling and analysis of the environmental conditions and hydrodynamic loads on the installed object as well as the installation equipment. This paper presents recommendations for modelling and analysis of deep water subsea lifting operations developed for the new DNV RP-H103 [1]. During installation of subsea structures, the highest dynamic forces are most often encountered in the splash zone. Recommendations for estimation of maximum forces will be presented. For small structures and tools, installation through the moon pool of a small installation vessel is often preferred. Calculation methods for loading on structures installed through a moon pool will be presented. During intervention or installation in deep water a significant amplification of amplitude and forces can be experienced when the frequency range of vertical crane tip motion coincides with the natural vertical oscillation of the lift wire and load. Vertical resonance may reduce the operability of the operation. Simplified calculation methods for such operations are presented. (Author)

  4. AMS gets lift on space shuttle Discovery

    CERN Multimedia

    2009-01-01

    AMS-02, the CERN-recognized experiment that will seek dark matter, missing matter and antimatter in Space aboard the International Space Station (ISS), has recently got the green light to be part of the STS-134 NASA mission in 2010. Installation of AMS detectors in the Prévessin experiment hall.In a recent press release, NASA announced that the last or last-but-one mission of the Space Shuttle programme would be the one that will deliver AMS, the Alpha Magnetic Spectrometer, to the International Space Station. The Space Shuttle Discovery is due to lift off in July 2010 from Kennedy Space Center and its mission will include the installation of AMS to the exterior of the space station, using both the shuttle and station arms. "It wasn’t easy to get a lift on the Space Shuttle from the Bush administration," says professor Samuel Ting, spokesperson of the experiment, "since during his administration all the funds for space research w...

  5. Effects of a Belt on Intra-Abdominal Pressure during Weight Lifting.

    Science.gov (United States)

    1988-03-01

    potentially injurious b compressive forces on spinal discs during lifting. To investigate the effects of a standard lifting belt on lAP and lifting mechanics... injurious compressive forces on spinal discs during lifting. To investigate the effects of a standard lifting belt on IAP and lifting ! mechanics... weightlifting (7,9). Both olympic and power lifters have used lifting belts for many years, yet virtually no research has been reported which examines

  6. ALARA review for the deactivation of 105-N Lift Station

    International Nuclear Information System (INIS)

    Nellesen, A.L.

    1997-01-01

    This ALARA review provides a description of the engineering and administrative controls used to manage personnel exposure and to control contamination levels and airborne radioactivity concentrations, while removing water, sludge, stabilizing surfaces, and all other associated work involved in the deactivation of the 105-N Lift Station. The lift station was used as a sump and received contaminated water from the 105-N Fuel Storage Basin weirs and contaminated drains in the 105-N Building. During operation water from the lift station was pumped to the 1310-N and 1325-N cribs. Deactivation of the lift station is a critical step in completing the deactivation of N-Area

  7. Sikkerhedsbestemmelser for beskæringsarbejde fra lift

    DEFF Research Database (Denmark)

    Jakobsen, Ole Sejr; Theilby, Frans

    2010-01-01

    Brug af lift til beskæring og fældning af træer er blevet udbredt i den grønne sektor. Som bruger er det vigtigt at kende den lift, man har valgt, og at arbejdet med motorsav foregår efter Arbejdstilsynets regler og anbefalinger.......Brug af lift til beskæring og fældning af træer er blevet udbredt i den grønne sektor. Som bruger er det vigtigt at kende den lift, man har valgt, og at arbejdet med motorsav foregår efter Arbejdstilsynets regler og anbefalinger....

  8. The ergonomics body posture on repetitive and heavy lifting activities of workers in aerospace manufacturing warehouse

    Science.gov (United States)

    Kamat, S. R.; Zula, N. E. N. Md; Rayme, N. S.; Shamsuddin, S.; Husain, K.

    2017-06-01

    Warehouse is an important entity in manufacturing organizations. It usually involves working activities that relate ergonomics risk factors including repetitive and heavy lifting activities. Aerospace manufacturing workers are prone of having musculoskeletal disorder (MSD) problems because of the manual handling activities. From the questionnaires is states that the workers may have experience discomforts experience during manual handling work. Thus, the objectives of this study are; to investigate the body posture and analyze the level of discomfort for body posture of the workers while performing the repetitive and heavy lifting activities that cause MSD problems and to suggest proper body posture and alternatives to reduce the MSD related problems. Methodology of this study involves interviews, questionnaires distribution, anthropometry measurements, RULA (Right Upper Limb Assessment) assessment sheet and CATIA V5 RULA analysis, NIOSH lifting index (LI) and recommended weight limit (RWL). Ten workers are selected for pilot study and as for anthropometry measurement all workers in the warehouse department were involved. From the first pilot study, the RULA assessment score in CATIA V5 shows the highest score which is 7 for all postures and results after improvement of working posture is very low hence, detecting weight of the material handling is not in recommendation. To reduce the risk of MSD through the improvisation of working posture, the weight limit is also calculated in order to have a RWL for each worker. Therefore, proposing a guideline for the aerospace workers involved with repetitive movement and excessive lifting will help in reducing the risk of getting MSD.

  9. Using verbal instructions to influence lifting mechanics - Does the directive "lift with your legs, not your back" attenuate spinal flexion?

    Science.gov (United States)

    Beach, Tyson A C; Stankovic, Tatjana; Carnegie, Danielle R; Micay, Rachel; Frost, David M

    2018-02-01

    "Use your legs" is commonly perceived as sound advice to prevent lifting-related low-back pain and injuries, but there is limited evidence that this directive attenuates the concomitant biomechanical risk factors. Body segment kinematic data were collected from 12 men and 12 women who performed a laboratory lifting/lowering task after being provided with different verbal instructions. The main finding was that instructing participants to lift "without rounding your lower back" had a greater effect on the amount of spine flexion they exhibited when lifting/lowering than instructing them to lift "with your legs instead of your back" and "bend your knees and hips". It was concluded that if using verbal instructions to discourage spine flexion when lifting, the instructions should be spine- rather than leg-focused. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Pig lift applications in offshore dry completion wells; Aplicacao do pig lift em pocos offshore de completacao seca

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Paulo C.R.; Faria, Rogerio Costa; Almeida, Alcino Resende [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2000-07-01

    Production increases of 10% to 130% have been obtained with pig lift installations on offshore oil wells in the Cacao Field, southeast Brazil. At the present time 3 wells out of 5 are being produced with pig lift. These deep, highly deviated wells with little space on the platform to the required surface equipment presented a challenge to pig lift technology. However, these difficulties were overcame and the benefits obtained helped to maintain the economical attractiveness of the platform. (author)

  11. Numerically-based ducted propeller design using vortex lattice lifting line theory

    OpenAIRE

    Stubblefield, John M.

    2008-01-01

    CIVINS (Civilian Institutions) Thesis document This thesis used vortex lattice lifting line theory to model an axisymmetrical-ducted propeller with no gap between the duct and the propeller. The theory required to model the duct and its interaction with the propeller were discussed and implemented in Open-source Propeller Design and Analysis Program (OpenProp). Two routines for determining the optimum circulation distribution were considered, and a method based on calculus of variation...

  12. AFC-Enabled Simplified High-Lift System Integration Study

    Science.gov (United States)

    Hartwich, Peter M.; Dickey, Eric D.; Sclafani, Anthony J.; Camacho, Peter; Gonzales, Antonio B.; Lawson, Edward L.; Mairs, Ron Y.; Shmilovich, Arvin

    2014-01-01

    The primary objective of this trade study report is to explore the potential of using Active Flow Control (AFC) for achieving lighter and mechanically simpler high-lift systems for transonic commercial transport aircraft. This assessment was conducted in four steps. First, based on the Common Research Model (CRM) outer mold line (OML) definition, two high-lift concepts were developed. One concept, representative of current production-type commercial transonic transports, features leading edge slats and slotted trailing edge flaps with Fowler motion. The other CRM-based design relies on drooped leading edges and simply hinged trailing edge flaps for high-lift generation. The relative high-lift performance of these two high-lift CRM variants is established using Computational Fluid Dynamics (CFD) solutions to the Reynolds-Averaged Navier-Stokes (RANS) equations for steady flow. These CFD assessments identify the high-lift performance that needs to be recovered through AFC to have the CRM variant with the lighter and mechanically simpler high-lift system match the performance of the conventional high-lift system. Conceptual design integration studies for the AFC-enhanced high-lift systems were conducted with a NASA Environmentally Responsible Aircraft (ERA) reference configuration, the so-called ERA-0003 concept. These design trades identify AFC performance targets that need to be met to produce economically feasible ERA-0003-like concepts with lighter and mechanically simpler high-lift designs that match the performance of conventional high-lift systems. Finally, technical challenges are identified associated with the application of AFC-enabled highlift systems to modern transonic commercial transports for future technology maturation efforts.

  13. Sensorimotor memory biases weight perception during object lifting

    Directory of Open Access Journals (Sweden)

    Vonne evan Polanen

    2015-12-01

    Full Text Available When lifting an object, the brain uses visual cues and an internal object representation to predict its weight and scale fingertip forces accordingly. Once available, tactile information is rapidly integrated to update the weight prediction and refine the internal object representation. If visual cues cannot be used to predict weight, force planning relies on implicit knowledge acquired from recent lifting experience, termed sensorimotor memory. Here, we investigated whether perception of weight is similarly biased according to previous lifting experience and how this is related to force scaling. Participants grasped and lifted series of light or heavy objects in a semi-randomized order and estimated their weights. As expected, we found that forces were scaled based on previous lifts (sensorimotor memory and these effects increased depending on the length of recent lifting experience. Importantly, perceptual weight estimates were also influenced by the preceding lift, resulting in lower estimations after a heavy lift compared to a light one. In addition, the weight estimations were negatively correlated with the magnitude of planned force parameters. This perceptual bias was only found if the current lift was light, but not heavy since the magnitude of sensorimotor memory effects had, according to Weber’s law, relatively less impact on heavy compared to light objects. A control experiment tested the importance of active lifting in mediating these perceptual changes and showed that when weights are passively applied on the hand, no effect of previous sensory experience is found on perception. These results highlight how fast learning of novel object lifting dynamics can shape weight perception and demonstrate a tight link between action planning and perception control. If predictive force scaling and actual object weight do not match, the online motor corrections, rapidly implemented to downscale forces, will also downscale weight estimation in

  14. Fatigue-related changes in the coordination of lifting and their effect of low back load

    NARCIS (Netherlands)

    Van Dieën, Jaap H.; Toussaint, Huub M.; Maurice, Cora; Mientjes, Martine

    1996-01-01

    In this study, changes in movement coordination caused by fatigue that developed during repetitive lifting were examined. Five men performed 6 times a 5-min bout of lifting an 8-kg barbell at 15 lifts/min, using two lifting techniques; one minimized trunk rotation (squat lift), and the other

  15. Fitness Tracker for Weight Lifting Style Workouts

    Energy Technology Data Exchange (ETDEWEB)

    Wihl, B. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-02-01

    This document proposes an early, high level design for a fitness tracking system which can automatically log weight lifting style workouts. The system will provide an easy to use interface both physically through the use of several wireless wristband style motion trackers worn on the limbs, and graphically through a smartphone application. Exercise classification will be accomplished by calibration of the user’s specific motions. The system will accurately track a user’s workout, miscounting no more than one repetition in every 20, have sufficient battery life to last several hours, work with existing smartphones and have a cost similar to those of current fitness tracking devices. This document presents the mission background, current state-of-theart, stakeholders and their expectations, the proposed system’s context and concepts, implementation concepts, system requirements, first sublevel function decomposition, possible risks for the system, and a reflection on the design process.

  16. Comparison of Methods of Teaching Children Proper Lifting ...

    African Journals Online (AJOL)

    Objective: This study was designed to determine the effects of three teaching methods on children\\'s ability to demonstrate and recall their mastery of proper lifting techniques. Method: Ninety-three primary five and six public school children who had no knowledge of proper lifting technique were assigned into three equal ...

  17. UF{sub 6} cylinder lifting equipment enhancements

    Energy Technology Data Exchange (ETDEWEB)

    Hortel, J.M. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

    1991-12-31

    This paper presents numerous enhancements that have been made to the Portsmouth lifting equipment to ensure the safe handling of cylinders containing liquid uranium hexafluoride (UF{sub 6}). The basic approach has been to provide redundancy to all components of the lift path so that any one component failure would not cause the load to drop or cause any undesirable movement.

  18. Effect of ship motion on spinal loading during manual lifting

    NARCIS (Netherlands)

    Faber, G.S.; Kingma, I.; Delleman, N.; Dieën, J. van

    2008-01-01

    This study investigated the effects of ship motion on peak spinal loading during lifting. All measurements were done on a ship at sea. In 1-min trials, which were repeated over a wide range of sailing conditions, subjects lifted an 18 kg box five times. Ship motion, whole body kinematics, ground

  19. Does the sensorimotor system minimize prediction error or select the most likely prediction during object lifting?

    Science.gov (United States)

    McGregor, Heather R.; Pun, Henry C. H.; Buckingham, Gavin; Gribble, Paul L.

    2016-01-01

    The human sensorimotor system is routinely capable of making accurate predictions about an object's weight, which allows for energetically efficient lifts and prevents objects from being dropped. Often, however, poor predictions arise when the weight of an object can vary and sensory cues about object weight are sparse (e.g., picking up an opaque water bottle). The question arises, what strategies does the sensorimotor system use to make weight predictions when one is dealing with an object whose weight may vary? For example, does the sensorimotor system use a strategy that minimizes prediction error (minimal squared error) or one that selects the weight that is most likely to be correct (maximum a posteriori)? In this study we dissociated the predictions of these two strategies by having participants lift an object whose weight varied according to a skewed probability distribution. We found, using a small range of weight uncertainty, that four indexes of sensorimotor prediction (grip force rate, grip force, load force rate, and load force) were consistent with a feedforward strategy that minimizes the square of prediction errors. These findings match research in the visuomotor system, suggesting parallels in underlying processes. We interpret our findings within a Bayesian framework and discuss the potential benefits of using a minimal squared error strategy. NEW & NOTEWORTHY Using a novel experimental model of object lifting, we tested whether the sensorimotor system models the weight of objects by minimizing lifting errors or by selecting the statistically most likely weight. We found that the sensorimotor system minimizes the square of prediction errors for object lifting. This parallels the results of studies that investigated visually guided reaching, suggesting an overlap in the underlying mechanisms between tasks that involve different sensory systems. PMID:27760821

  20. Object properties and cognitive load in the formation of associative memory during precision lifting.

    Science.gov (United States)

    Li, Yong; Randerath, Jennifer; Bauer, Hans; Marquardt, Christian; Goldenberg, Georg; Hermsdörfer, Joachim

    2009-01-03

    When we manipulate familiar objects in our daily life, our grip force anticipates the physical demands right from the moment of contact with the object, indicating the existence of a memory for relevant object properties. This study explores the formation and consolidation of the memory processes that associate either familiar (size) or arbitrary object features (color) with object weight. In the general task, participants repetitively lifted two differently weighted objects (580 and 280 g) in a pseudo-random order. Forty young healthy adults participated in this study and were randomly distributed into four groups: Color Cue Single task (CCS, blue and red, 9.8(3)cm(3)), Color Cue Dual task (CCD), No Cue (NC) and Size Cue (SC, 9.8(3) and 6(3)cm(3)) group. All groups performed a repetitive precision grasp-lift task and were retested with the same protocol after a 5-min pause. The CCD group was also required to simultaneously perform a memory task during each lift of differently weighted objects coded by color. The results show that groups lifting objects with arbitrary or familiar features successfully formed the association between object weight and manipulated object features and incorporated this into grip force programming, as observed in the different scaling of grip force and grip force rate for different object weights. An arbitrary feature, i.e., color, can be sufficiently associated with object weight, however with less strength than the familiar feature of size. The simultaneous memory task impaired anticipatory force scaling during repetitive object lifting but did not jeopardize the learning process and the consolidation of the associative memory.

  1. Maximum Acceptable Weight of Lift reflects peak lumbosacral extension moments in a Functional Capacity Evaluation test using free style, stoop, and squat lifting

    NARCIS (Netherlands)

    Kuijer, P.P.F.M.; van Oostrom, S.H.; Duijzer, K.; van Dieen, J.H.

    2012-01-01

    It is unclear whether the maximum acceptable weight of lift (MAWL), a common psychophysical method, reflects joint kinetics when different lifting techniques are employed. In a within-participants study (n = 12), participants performed three lifting techniques - free style, stoop and squat lifting

  2. Maximum acceptable weight of lift reflects peak lumbosacral extension moments in a functional capacity evaluation test using free style, stoop and squat lifting

    NARCIS (Netherlands)

    Kuijer, P. P. F. M.; van Oostrom, S. H.; Duijzer, K.; van Dieën, J. H.

    2012-01-01

    It is unclear whether the maximum acceptable weight of lift (MAWL), a common psychophysical method, reflects joint kinetics when different lifting techniques are employed. In a within-participants study (n = 12), participants performed three lifting techniques - free style, stoop and squat lifting

  3. A comparative analysis of lumbar spine mechanics during barbell- and crate-lifting: implications for occupational lifting task assessments.

    Science.gov (United States)

    Zehr, Jackie D; Carnegie, Danielle R; Welsh, Timothy N; Beach, Tyson A C

    2018-03-19

    To compare the effects of object handled and handgrip used on lumbar spine motion and loading during occupational lifting task simulations. Eight male and eight female volunteers performed barbell and crate lifts with a pronated (barbell) and a neutral (crate) handgrip. The mass of barbells/crates lifted was identical across the objects and fixed at 11.6 and 9.3 kg for men and women, respectively. The initial heights of barbells/crates were individualized to mid-shank level. Body segment kinematics and foot-ground reaction kinetics were collected, and then input into an electromyography-assisted dynamic biomechanical model to quantify lumbar spine motion and loading. Lumbar compression and net lumbosacral moment magnitudes were 416 N and 17 Nm lower when lifting a barbell than when lifting a crate (p  0.392) or flexion/extension velocities (p > 0.085). Crate- and barbell-lifting tasks can be used interchangeably if assessing lifting mechanics based on peak spine motion variables. If assessments are based on the spine loading responses to task demands, however, then crate- and barbell-lifting tasks cannot be used interchangeably.

  4. Impact of the initial streamwise inclination of a double jet emitted within a cool crossflow on its temperature field and pollutants dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Radhouane, A.; Mahjoub Said, Nejla; Mhiri, H. [Ecole Nationale d' Ingenieurs de Monastir, Unite de Thermique et Thermodynamique des Procedes Industriels, Monastir (Tunisia); Palec, G. le; Bournot, P. [IUSTI, UMR 6595, Technopole de Chateau-Gombert, Marseille (France)

    2009-04-15

    An experimental study and a numerical modeling are carried out simultaneously on a twin inclined jets' configuration issuing into a cooler crossflow. The main purpose of this study is to track the overall evolution of the jets among the surrounding flow and then determine the thermal and mass transfer features that characterize the resulting flowfield. The experimental data are depicted by means of a particle image velocimetry technique; whereas the numerical three-dimensional model is simulated through the resolution of the different governing Navier-Stokes' equations by means of the finite volume method. Two different closure models were tested: the standard k-{epsilon} model and the Reynolds stress model (RSM) second order model. The introduction of the latter in such a configuration brings some valuable improvement since it allows the detection of the slightest variations within the domain and then describes the least occurring mechanisms. The confrontation of the differently processed numerical results with the experimentally tracked data comforted our opinion since it proved the better efficiency of the RSM model for the description of the handled flow; that's why we adopted it for the rest of the paper. Once the validation obtained, we proceeded to the evaluation of the influence of the initial streamwise inclination of the emitted jets on the engendered thermal field and on the pollutants' dispersion. For the matter, we tested the following angles: 30 , 45 , 60 and 90 . After that, we represented the temperature variation along different directions in order to detail its behavior in all of them and at different levels. This characterization is highly recommended since it may promote the efficiency of several applications (mainly the cooling applications). We also evaluated the influence of this same parameter; the initial inclination; on the pollutants' dispersion due to the high and alarming importance of the problem on the

  5. Maximum Acceptable Weight of Lift reflects peak lumbosacral extension moments in a Functional Capacity Evaluation test using free style, stoop, and squat lifting

    OpenAIRE

    Kuijer, P.P.F.M.; van Oostrom, S.H.; Duijzer, K.; van Dieen, J.H.

    2012-01-01

    It is unclear whether the maximum acceptable weight of lift (MAWL), a common psychophysical method, reflects joint kinetics when different lifting techniques are employed. In a within-participants study (n = 12), participants performed three lifting techniques - free style, stoop and squat lifting from knee to waist level - using the same dynamic functional capacity evaluation lifting test to assess MAWL and to calculate low back and knee kinetics. We assessed which knee and back kinetic para...

  6. The liquid lift: Looking natural without lumps

    Directory of Open Access Journals (Sweden)

    Iñigo de Felipe

    2015-01-01

    Full Text Available Context: Hyaluronic acid (HA is the most common filler used to rejuvenate. Today, a three-dimensional approach prevails over previous techniques in which this material was used in specific areas of the face such as the nasolabial fold, the marionette line, and the eye trough giving a strange appearance that does not look natural. Even with a volumizing purpose, the injection of HA can sometimes produce clinically detectable nodules or lumps where the filler is deposited. Aims: To develop a new technique of injecting HA that can provide more natural results and avoid the lumpiness and nodular appearance that sometimes occurs with the injection of HA. To detect whether mixing HA with diluted anesthetic agent modifies its behavior. Settings and Design: Prospective, case control, single-center study on a private clinic setting. Materials and Methods: Eighty six patients were enrolled in this study. All of them had a previous treatment with nondiluted HA using a needle at least a year before. Patients were injected with 8 mL of reticulated HA (RHA mixed with 6 mL of saline and 2 mL of anesthetic agent. The mixture was administered through a cannula inserted in the face, one at mid-cheek and another at frontal-temporal point of entry. Owing to the lifting effect of this mixture we called this procedure liquid lift (LL. Patients were evaluated 1 month, 6 months, and a year later and asked to compare the LL with previous experiences in terms of natural look, pain, and appearance of nodules. Statistical Analysis Used: Student′s t-test. Results: One month after the treatment, 83 out of 86 patients (96.5% thought LL produced a more natural look than the previous treatment with the needle. Sixty two (72% considered LL less painful than the previous treatment and only eight (9.3% could detect lumps or nodules 1 month after LL was performed compared with 46 (53.5% that described this problem with previous needle injections. The incidence of bruising was

  7. 'Natural Gas lift', a New Tool for Nigeria

    International Nuclear Information System (INIS)

    Lucas, C. D.

    2003-01-01

    Gas lift is the most common means of artificial lift in the Niger Delta and has been widely applied worldwide. The advent of remote monitoring and control devises (RMC) has added a new option in artificiallift, 'natural gas lift'. 'Natural gas lift' is an extension RMC in which a gas zone and one or more oil zones are produced through the same tubing string, using the gas enhance the production of the oil zones. The flow of gas is maintained in the optimal range using down hole chokes that are controlled from the surface. The gas flow rate is monitored using downhole pressure and .temperature gauges. The use of 'natural gas lift' has the advantages of gas lift but without the cost associated with gas lift; gas supply wells, compression etc. This is especially critical in areas that are remote from other facilities or in subsea completions where access to the wells is limited. Stacked reservoirs and frequent inclusion of both oil and gas reservoirs in the same field, as found in the Niger Delta, makes Nigeria a prime candidate for this technology. An example of this production from the North Sea will be presented along with a potential application using data from the Niger Delta. Design elements of the monitoring and control systems will be covered and the advantages and drawbacks of this application will be discussed

  8. EMG Processing Based Measures of Fatigue Assessment during Manual Lifting

    Directory of Open Access Journals (Sweden)

    E. F. Shair

    2017-01-01

    Full Text Available Manual lifting is one of the common practices used in the industries to transport or move objects to a desired place. Nowadays, even though mechanized equipment is widely available, manual lifting is still considered as an essential way to perform material handling task. Improper lifting strategies may contribute to musculoskeletal disorders (MSDs, where overexertion contributes as the highest factor. To overcome this problem, electromyography (EMG signal is used to monitor the workers’ muscle condition and to find maximum lifting load, lifting height and number of repetitions that the workers are able to handle before experiencing fatigue to avoid overexertion. Past researchers have introduced several EMG processing techniques and different EMG features that represent fatigue indices in time, frequency, and time-frequency domain. The impact of EMG processing based measures in fatigue assessment during manual lifting are reviewed in this paper. It is believed that this paper will greatly benefit researchers who need a bird’s eye view of the biosignal processing which are currently available, thus determining the best possible techniques for lifting applications.

  9. EMG Processing Based Measures of Fatigue Assessment during Manual Lifting

    Science.gov (United States)

    Marhaban, M. H.; Abdullah, A. R.

    2017-01-01

    Manual lifting is one of the common practices used in the industries to transport or move objects to a desired place. Nowadays, even though mechanized equipment is widely available, manual lifting is still considered as an essential way to perform material handling task. Improper lifting strategies may contribute to musculoskeletal disorders (MSDs), where overexertion contributes as the highest factor. To overcome this problem, electromyography (EMG) signal is used to monitor the workers' muscle condition and to find maximum lifting load, lifting height and number of repetitions that the workers are able to handle before experiencing fatigue to avoid overexertion. Past researchers have introduced several EMG processing techniques and different EMG features that represent fatigue indices in time, frequency, and time-frequency domain. The impact of EMG processing based measures in fatigue assessment during manual lifting are reviewed in this paper. It is believed that this paper will greatly benefit researchers who need a bird's eye view of the biosignal processing which are currently available, thus determining the best possible techniques for lifting applications. PMID:28303251

  10. Clinical Comparison of Sinus Lift via Summers Osteotomy and Piezosurgery

    Directory of Open Access Journals (Sweden)

    Mehrdad Radvar

    2017-12-01

    Full Text Available Introduction: Sinus lift is a process that could be performed by two methods. In the closed sinus lift, hybrid materials enter a suitable position through a created cavity. Afterwards, the materials are pressed without damaging the sinus membrane, and the implants are usually placed at the same time. Closed sinus lift is carried out via osteotomy and piezosurgery, and each of the techniques has certain advantages and limitations. The present study aimed to compare the clinical results of closed sinus lift using the summers osteotomy and piezosurgery. Materials and Methods: In this study, 20 patients requiring dental implants in the posterior segment of the maxilla via sinus lift surgery were randomly divided into two groups. The first group received piezosurgery, and the second group underwent summers osteotomy for sinus lift. Postoperative Schneiderian membrane perforation, inflammation, pain, bone gain, and bone loss were compared between the groups six months after the surgery using Mann-Whitney U test and two-sample t-test. Results: In the groups receiving piezosurgery and summers osteotomy, mean sinus lift was 3.6±0.9 and 4.0±2.2 mm, pain score was 1.1±1.2 and 0.9±0.8, bone gain was 2.2±0.8 and 3.1±1.3 mm, and crestal bone loss was 1.1±1.2 and 0.9±0.8 mm, respectively. Moreover, no Schneiderian membrane perforation was observed in the two methods, and the differences between the groups were not considered significant (P>0.05. Conclusion: According to the results, the clinical outcomes of piezosurgery in sinus lift are similar to those of summers osteotomy. Therefore, piezosurgery could be a proper alternative to summers osteotomy in sinus lift surgery.

  11. CH-53K Heavy Lift Replacement Helicopter (CH-53K)

    Science.gov (United States)

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-390 CH-53K Heavy Lift Replacement Helicopter (CH-53K) As of FY 2017 President’s Budget...December 2015 SAR March 4, 2016 10:04:18 UNCLASSIFIED 4 Col Henry Vanderborght PMA-261 Heavy Lift Helicopters Program Executive Office - Air, Anti...757-5780 Fax: 301-757-5109 DSN Phone: 757-5780 DSN Fax: 757-5109 Date Assigned: May 29, 2014 Program Information Program Name CH-53K Heavy Lift

  12. Heavy Lift Launch Capability with a New Hydrocarbon Engine

    Science.gov (United States)

    Threet, Grady E., Jr.; Holt, James B.; Philips, Alan D.; Garcia, Jessica A.

    2011-01-01

    The Advanced Concepts Office at NASA's George C. Marshall Space Flight Center was tasked to define the thrust requirement of a new liquid oxygen rich staged combustion cycle hydrocarbon engine that could be utilized in a launch vehicle to meet NASA s future heavy lift needs. Launch vehicle concepts were sized using this engine for different heavy lift payload classes. Engine out capabilities for one of the heavy lift configurations were also analyzed for increased reliability that may be desired for high value payloads or crewed missions. The applicability for this engine in vehicle concepts to meet military and commercial class payloads comparable to current ELV capability was also evaluated.

  13. Development of a Marine Propeller With Nonplanar Lifting Surfaces

    DEFF Research Database (Denmark)

    Andersen, Poul; Friesch, Jürgen; Kappel, Jens J.

    2005-01-01

    The principle of non-planar lifting surfaces is applied to the design of modern aircraft wings to obtain better lift to drag ratios. Whereas a pronounced fin or winglet at the wingtip has been developed for aircraft, the application of the nonplanar principle to marine propellers, dealt...... with in this paper, has led to the KAPPEL propeller with blades curved toward the suction side integrating the fin or winglet into the propeller blade. The combined theoretical, experimental, and practical approach to develop and design marine propellers with nonplanar lifting surfaces has resulted in propellers...

  14. Lifted Java: A Minimal Calculus for Translation Polymorphism

    DEFF Research Database (Denmark)

    Ingesman, Matthias Diehn; Ernst, Erik

    2011-01-01

    To support roles and similar notions involving multiple views on an object, languages like Object Teams and CaesarJ include mechanisms known as lifting and lowering. These mechanisms connect pairs of objects of otherwise unrelated types, and enables programmers to consider such a pair almost...... of translation polymorphism has not been proved. This paper presents a simple model that extends Featherweight Java with the core operations of translation polymorphism, provides a Coq proof that its type system is sound, and shows that the ambiguity problem associated with the so-called smart lifting mechanism...... can be eliminated by a very simple semantics for lifting....

  15. Neurologic disorders associated with weight lifting and bodybuilding.

    Science.gov (United States)

    Busche, Kevin

    2009-02-01

    Weight lifting and other forms of strength training are becoming more common because of an increased awareness of the need to maintain individual physical fitness. Emergency room data indicate that injuries caused by weight training have become more universal over time, likely because of increased participation rates. Neurologic injuries can result from weight lifting and related practices. Although predominantly peripheral nervous system injuries have been described, central nervous system disease may also occur. This article illustrates the types of neurologic disorders associated with weight lifting.

  16. Autoignited laminar lifted flames of methane, ethylene, ethane, and n-butane jets in coflow air with elevated temperature

    KAUST Repository

    Choi, Byungchul; Chung, Suk-Ho

    2010-01-01

    regimes depending on the initial temperature and fuel mole fraction: (1) non-autoignited lifted flame, (2) autoignited lifted flame with tribrachial (or triple) edge, and (3) autoignited lifted flame with mild combustion. For the non-autoignited lifted

  17. Business Profile of Boat Lift Net and Stationary Lift Net Fishing Gear in Morodemak Waters Central Java

    Science.gov (United States)

    Hapsari, Trisnani D.; Jayanto, Bogi B.; Fitri, Aristi D. P.; Triarso, I.

    2018-02-01

    Lift net is one of the fishing gears that is used widely in the Morodemak coastal fishing port (PPP) for catching pelagic fish. The yield of fish captured by these fishing gear has high economic value, such as fish belt (Trichiurus sp), squids (Loligo sp) and anchovies (Stelophorus sp). The aims of this research were to determine the technical aspects of boat lift net and stationary lift net fishing gear in Morodemak Waters Demak Regency; to find out the financial aspect of those fishing gears and to analyze the financial feasibility by counting PP, NPV, IRR, and B/C ratio criteria. This research used case study method with descriptive analysis. The sampling method was purposive sampling with 22 fishermen as respondents. The result of the research showed that the average of boat lift net acceptance was Rp 388,580,000. The financial analysis of fisheries boat lift net with the result of NPV Rp 836,149,272, PP 2.44 years, IRR value 54%, and B/C ratio 1.73. The average of stationary lift net acceptance was Rp 27,750,000. The financial analysis lift net with the result of NPV Rp 37,937,601; PP 1.96 years, IRR value 86%, and B/C ratio 1.32. This research had a positive NPV value, B/C ratio >1, and IRR > discount rate (12 %). This study concluded that the fishery business of boat lift net and stationary lift net in Morodemak coastal fishing port (PPP) was worth running.

  18. Linnainstallatsioonide festival Tallinnas 2011 ehk "Lift11" / Margit Aule

    Index Scriptorium Estoniae

    Aule, Margit

    2011-01-01

    Tallinna linnainstallatsioonide festivalist "LIFT11", konkursist. 10 installatsioonist (nimetatud autorid), millest avlikku ruumi on jõudnud 8 installatsiooni. Intervjuu installatsiooni "Face it", mille sünd on veel kahtluse all, autorite Argo Peeveri ja Margus Tammega

  19. "LIFT11" lõpetab installatsioon "Rada metsas" / Margit Aule

    Index Scriptorium Estoniae

    Aule, Margit

    2011-01-01

    Kadrioru pargis 24.09.-22.10.2011 avatud jaapani arhitekti Tetsuo Kondo installatsioonist "Rada metsas", linnainstallatsioonide festivali LIFT11 viimasest ja suurimast teosest. Installatsiooni on rahastanud Jaapani Fond. Arhitektist

  20. Vertical Lift by Series Hybrid Power, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — A major market for vertical lift aircraft is in urban operations, primarily for police and electronic news gathering (typically a Bell 206 or a Eurocopter AS350)....

  1. Lift-(gasless) laparoscopic surgery under regional anesthesia.

    Science.gov (United States)

    Kruschinski, Daniel; Homburg, Shirli

    2005-01-01

    The objective of this Chapter was to investigate the feasibility and outcome of gasless laparoscopy under regional anesthesia. A prospective evaluation of Lift-(gasless) laparoscopic procedures under regional anesthesia (Canadian Task Force classification II-1) was done at three endoscopic gynecology centers (franchise system of EndGyn(r)). Sixty-three patients with gynecological diseases comprised the cohort. All patients underwent Lift-laparoscopic surgery under regional anesthesia: 10 patients for diagnostic purposes, 17 for surgery of ovarian tumors, 14 to remove fibroids, and 22 for hysterectomies. All patients were operated without conversion to general anesthesia and without perioperative or anesthesiologic complications. Lift-laparoscopy under regional anesthesia can be recommended to all patients who desire laparoscopic intervention without general anesthesia. For elderly patients, those with cardiopulmonary risks, during pregnancy, or with contraindications for general anesthesia, Lift-laparoscopy under regional anesthesia should be the procedure of choice.

  2. Operation of flooded wells by the gas-lift method

    Energy Technology Data Exchange (ETDEWEB)

    Li, G S; Kabirov, M M; Nigay, Yu V

    1983-01-01

    A study is made of the factors which influence the effectiveness of operation of the gas-lift lifter during progressive flooding of a well. The law governing the change in its efficiency under the given conditions is also examined.

  3. Factors associated with high physical exertion during manual lifting

    DEFF Research Database (Denmark)

    Andersen, Lars L.; Sundstrup, Emil; Brandt, Mikkel

    2018-01-01

    BACKGROUND: High physical exertion during work is a risk factor for back pain and long-term sickness absence. OBJECTIVE: To investigate which factors are associated with physical exertion during manual lifting. METHODS: From 14 workplaces across Denmark, 200 blue-collar workers reported perceived...... physical exertion (Borg-CR10) during manual lifting from floor to table height of 5, 10, 20 and 30 kg at the beginning and end of the working day. The workers also responded to a questionnaire and went through testing of isometric back muscle strength. Associations were modelled using logistic regression...... during manual lifting in blue-collar workers. These factors should be considered when planning work with manual lifting for individual workers....

  4. Lifting of a sector block for YE-2 at Kawasaki.

    CERN Multimedia

    R. Loveless/U. of Wisconsin

    2000-01-01

    YE-2 is build from machined sector blocks. Trial assembly is carried out horizontally. This picture represents the lifting of a machined sector block destined to the trial assembly of a half disk YE-2 at Kawasaki (KHI) Kobe, Japan.

  5. Experimental Investigation of a Lift Augmented Ground Effect Platform

    National Research Council Canada - National Science Library

    Igue, Roberto T

    2005-01-01

    .... Lift, torque and efficiency were measured and calculated for each setting. Pressure and velocity information was also collected at specific points around the craft when operating at different heights above ground...

  6. Outgoing Cuntz scattering system for a coisometric lifting and ...

    Indian Academy of Sciences (India)

    Multivariate operator theory; row contraction; contractive lifting; outgoing. Cuntz scattering system ... multivariate operator setting. In § 3 we study the ..... Our goal is to find an outgoing Cuntz scattering system inside our model. Let as before.

  7. Simultaneous oroantral communication closure, sinus‑lifting, and ...

    African Journals Online (AJOL)

    2015-10-10

    Oct 10, 2015 ... Dr. S Yanik,. Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, ... dental implants, and they require sinus‑lifting procedures long after the .... by some researchers, including third molar transplantation,. Figure 1: ...

  8. Searching for ski-lift injury: an uphill struggle?

    Science.gov (United States)

    Smartt, Pam; Chalmers, David

    2010-03-01

    Injuries arising from ski-lift malfunction are rare. Most arise from skier error when embarking or disembarking, or from improper lift operation. A search of the literature failed to uncover any studies focusing specifically on ski-lift injuries. The purpose of this study was to identify and characterise ski-lift injury resulting in hospitalisation and comment on barriers to reporting and reporting omissions. New Zealand hospitalised injury discharges 2000-2005 formed the primary dataset. To aid case identification these data were linked to ACC compensated claims for the same period and the data searched for all hospitalised cases of injury arising from ski-lifts. 44 cases were identified representing 2% of snow-skiing/snowboarding cases. 28 cases (64%) were male and 16 (36%) female, the average age was 32 yrs (range 5-73 yrs). The majority of cases were snow-skiers (35 cases, 80%). Most of the injuries were serious, or potentially so, with 1 case of traumatic pneumothorax, one of pulmonary embolism (after jumping from a ski-lift) and 28 cases sustaining fractures (six to the neck-of-femur, one to the lumbar spine and one to the pubis). ICISS scores for all cases ranged from 1.00 to 0.8182 (probability of dying in hospital 0-18.18%). Only 14 (32%) cases could be easily identified from ICD-10-AM e-codes and activity codes in the discharge summary. The ICD-10-AM external cause code for ski-lift injury V98 ("other specified transport accidents") was only assigned to 39% of cases. The type of ski-lift could only be determined in 24 cases (55%). Copyright 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  9. A New Perceptual Mapping Model Using Lifting Wavelet Transform

    OpenAIRE

    Taha TahaBasheer; Ehkan Phaklen; Ngadiran Ruzelita

    2017-01-01

    Perceptual mappingapproaches have been widely used in visual information processing in multimedia and internet of things (IOT) applications. Accumulative Lifting Difference (ALD) is proposed in this paper as texture mapping model based on low-complexity lifting wavelet transform, and combined with luminance masking for creating an efficient perceptual mapping model to estimate Just Noticeable Distortion (JND) in digital images. In addition to low complexity operations, experiments results sho...

  10. NASA safety standard for lifting devices and equipment

    Science.gov (United States)

    1990-09-01

    NASA's minimum safety requirements are established for the design, testing, inspection, maintenance, certification, and use of overhead and gantry cranes (including top running monorail, underhung, and jib cranes), mobile cranes, derrick hoists, and special hoist supported personnel lifting devices (these do not include elevators, ground supported personnel lifts, or powered platforms). Minimum requirements are also addressed for the testing, inspection, and use of Hydra-sets, hooks, and slings. Safety standards are thoroughly detailed.

  11. Managing cultural diversity in healthcare partnerships: the case of LIFT.

    Science.gov (United States)

    Mannion, Russell; Brown, Sally; Beck, Matthias; Lunt, Neil

    2011-01-01

    The National Health Service (NHS) Local Improvement Finance Trust (LIFT) programme was launched in 2001 as an innovative public-private partnership to address the historical under-investment in local primary care facilities in England. The organisations from the public and private sector that comprise a local LIFT partnership each have their own distinctive norms of behaviour and acceptable working practices - ultimately different organisational cultures. The purpose of this article is to assess the role of organisational culture in facilitating (or impeding) LIFT partnerships and to contribute to an understanding of how cultural diversity in public-private partnerships is managed at the local level. The approach taken was qualitative case studies, with data gathering comprising interviews and a review of background documentation in three LIFT companies purposefully sampled to represent a range of background factors. Elite interviews were also conducted with senior policy makers responsible for implementing LIFT policy at the national level. Interpreting the data against a conceptual framework designed to assess approaches to managing strategic alliances, the authors identified a number of key differences in the values, working practices and cultures in public and private organisations that influenced the quality of joint working. On the whole, however, partners in the three LIFT companies appeared to be working well together, with neither side dominating the development of strategy. Differences in culture were being managed and accommodated as partnerships matured. As LIFT develops and becomes the primary source of investment for managing, developing and channelling funding into regenerating the primary care infrastructure, further longitudinal work might examine how ongoing partnerships are working, and how changes in the cultures of public and private partners impact upon wider relationships within local health economies and shape the delivery of patient care

  12. EFFECT OF HEEL LIFTS ON PATELLOFEMORAL JOINT STRESS DURING RUNNING.

    Science.gov (United States)

    Mestelle, Zachary; Kernozek, Thomas; Adkins, Kelly S; Miller, Jessica; Gheidi, Naghmeh

    2017-10-01

    Patellofemoral pain is a debilitating injury for many recreational runners. Excessive patellofemoral joint stress may be the underlying source of pain and interventions often focus on ways to reduce patellofemoral joint stress. Heel lifts have been used as an intervention within Achilles tendon rehabilitation programs and to address leg length discrepancies. The purpose of this study was to examine the effect of running with heel lifts on patellofemoral joint stress, patellofemoral stress impulse, quadriceps force, step length, cadence, and other related kinematic and spatiotemporal variables. A repeated-measures research design. Sixteen healthy female runners completed five running trials in a controlled laboratory setting with and without 11mm heel lifts inserted in a standard running shoe. Kinetic and kinematic data were used in combination with a static optimization technique to estimate individual muscle forces. These data were inserted into a patellofemoral joint model which was used to estimate patellofemoral joint stress and other variables during running. When running with heel lifts, peak patellofemoral joint stress and patellofemoral stress impulse were reduced by a 4.2% (p=0.049) and 9.3% (p=0.002). Initial center of pressure was shifted anteriorly 9.1% when running with heel lifts (p0.05) were shown between conditions. Heel lift use resulted in decreased patellofemoral joint stress and impulse without associated changes in step length or frequency, or other variables shown to influence patellofemoral joint stress. The center of pressure at initial contact was also more anterior using heel lifts. The use of heel lifts may have therapeutic benefits for runners with patellofemoral pain if the primary goal is to reduce patellofemoral joint stress. 3b.

  13. The Exergy of Lift and Aircraft Exergy Flow Diagrams

    OpenAIRE

    Paulus, Jr., David; Gaggioli, Richard

    2010-01-01

    Aside from incidental, auxiliary loads, in level flight the principal load on the aircraft propulsion engine is the power required to provide the continuous lift. To construct an exergy flow diagram for an aircraft – for example, for the purpose of pinpointing inefficiencies and for costing – an expression is needed for the exergy delivered to and by the wings. That is, an expression is needed for the exergy of lift. The purpose of this paper is to present an expression de...

  14. Motor of Lift RSG-GAS Performance Analysis after Repair

    International Nuclear Information System (INIS)

    Asep-Saepuloh; Yayan-Andriyanto; Yuyut-Suraniyanto

    2006-01-01

    The out of order an equipment is ordinary natural process happened, above all the equipment be used continually with very old time, as for as out of order can be resulted from kinds of cause. Lift motor out of order can be result by motor is broken or happened the body shorten then affected do not function it the lift, so until done rewinding process. The rewinding is furl to repeat at motor coils. Motor of Lift represent main activator machine turning around shares pulley. Lift Motor will work if there is called in normal operation condition or the moment manual switch if done maintenance. Motor used at lift is motor three phases with two speeds that is low speed and high speed. Rewinding process must be done removed the motor from Lift machine and have to be done by professional workshop. In during function test take place, temperature at coil reach 70 o C (exceeding boundary permitted). After done installation addition thermal at motor coil hence his temperature become normal that is only reach 50 o C. (author)

  15. The drag and lift of different non-spherical particles from low to high Re

    Science.gov (United States)

    Sanjeevi, Sathish K. P.; Padding, Johan

    2017-11-01

    The present work investigates a simplified drag and lift model that can be used for different non-spherical particles. The flow around different non-spherical particles is studied using a multi-relaxation-time lattice Boltzmann method. We compute the mean drag coefficient CD , ϕ at different incident angles ϕ for a wide range of Reynolds numbers (Re). We show that the sine-squared drag law CD , ϕ =CD , ϕ =0° +(CD , ϕ =90° -CD , ϕ =0°) sin2 ϕ holds up to large Reynolds numbers Re = 2000 . The sine-squared dependence of CD occurs at Stokes flow (very low Re) due to linearity of the flow fields. We explore the physical origin behind the sine-squared law at high Re , and reveal that surprisingly, this does not occur due to linearity of flow fields. Instead, it occurs due to an interesting pattern of pressure distribution contributing to the drag, at higher Re , for different incident angles. Similarly, we find that the equivalent theoretical equation of lift coefficient CL can provide a decent approximation, even at high Re , for elongated particles. Such a drag and lift law valid at high Re is very much useful for Euler-Lagrangian fluidization simulations of the non-spherical particles. European Research Council (ERC) consolidator Grant scheme, Contract No. 615096 (NonSphereFlow).

  16. An experimental investigation of the flow physics of high-lift systems

    Science.gov (United States)

    Thomas, Flint O.; Nelson, R. C.

    1995-01-01

    This progress report is a series of overviews outlining experiments on the flow physics of confluent boundary layers for high-lift systems. The research objectives include establishing the role of confluent boundary layer flow physics in high-lift production; contrasting confluent boundary layer structures for optimum and non-optimum C(sub L) cases; forming a high quality, detailed archival data base for CFD/modelling; and examining the role of relaminarization and streamline curvature. Goals of this research include completing LDV study of an optimum C(sub L) case; performing detailed LDV confluent boundary layer surveys for multiple non-optimum C(sub L) cases; obtaining skin friction distributions for both optimum and non-optimum C(sub L) cases for scaling purposes; data analysis and inner and outer variable scaling; setting-up and performing relaminarization experiments; and a final report establishing the role of leading edge confluent boundary layer flow physics on high-lift performance.

  17. 75 FR 27662 - Special Conditions: Boeing 747-468, Installation of a Medical Lift

    Science.gov (United States)

    2010-05-18

    ... electrical motors, mounted to the rear wall, between the struts. A lifting gear-drive with shafts and gear... OPERATE LIFT DURING TAXI, TAKEOFF, LANDING, OR TURBULENCE. c. AN APPROVED MEDICAL STRETCHER OR WHEELCHAIR... operation. b. Operate the lift. c. Stow the lift for non-operation such as during TTL and turbulence. d...

  18. Autoignited lifted flames of dimethyl ether in heated coflow air

    KAUST Repository

    Al-Noman, Saeed M.

    2018-05-16

    Autoignited lifted flames of dimethyl ether (DME) in laminar nonpremixed jets with high-temperature coflow air have been studied experimentally. When the initial temperature was elevated to over 860 K, an autoignition occurred without requiring an external ignition source. A planar laser-induced fluorescence (PLIF) technique for formaldehyde (CH2O) visualized qualitatively the zone of low temperature kinetics in a premixed flame. Two flame configurations were investigated; (1) autoignited lifted flames with tribrachial edge having three distinct branches of a lean and a rich premixed flame wings with a trailing diffusion flame and (2) autoignited lifted flames with mild combustion when the fuel was highly diluted. For the autoignited tribrachial edge flames at critical autoignition conditions, exhibiting repetitive extinction and re-ignition phenomena near a blowout condition, the characteristic flow time (liftoff height scaled with jet velocity) was correlated with the square of the ignition delay time of the stoichiometric mixture. The liftoff heights were also correlated as a function of jet velocity times the square of ignition delay time. Formaldehydes were observed between the fuel nozzle and the lifted flame edge, emphasizing a low-temperature kinetics for autoignited lifted flames, while for a non-autoignited lifted flame, formaldehydes were observed near a thin luminous flame zone.For the autoignited lifted flames with mild combustion, especially at a high temperature, a unique non-monotonic liftoff height behavior was observed; decreasing and then increasing liftoff height with jet velocity. This behavior was similar to the binary mixture fuels of CH4/H2 and CO/H2 observed previously. A transient homogeneous autoignition analysis suggested that such decreasing behavior with jet velocity can be attributed to partial oxidation characteristics of DME in producing appreciable amounts of CH4/CO/H2 ahead of the edge flame region.

  19. Heavy Lift Launch Capability with a New Hydrocarbon Engine (NHE)

    Science.gov (United States)

    Threet, Grady E., Jr.; Holt, James B.; Philips, Alan D.; Garcia, Jessica A.

    2011-01-01

    The Advanced Concepts Office (ACO) at NASA Marshall Space Flight Center has analyzed over 2000 Ares V and other heavy lift concepts in the last 3 years. These concepts were analyzed for Lunar Exploration Missions, heavy lift capability to Low Earth Orbit (LEO) as well as exploratory missions to other near earth objects in our solar system. With the pending retirement of the Shuttle fleet, our nation will be without a civil heavy lift launch capability, so the future development of a new heavy lift capability is imperative for the exploration and large science missions our Agency has been tasked to deliver. The majority of the heavy lift concepts analyzed by ACO during the last 3 years have been based on liquid oxygen / liquid hydrogen (LOX/LH2) core stage and solids booster stage propulsion technologies (Ares V / Shuttle Derived and their variants). These concepts were driven by the decisions made from the results of the Exploration Systems Architecture Study (ESAS), which in turn, led to the Ares V launch vehicle that has been baselined in the Constellation Program. Now that the decision has been made at the Agency level to cancel Constellation, other propulsion options such as liquid hydrocarbon fuels are back in the exploration trade space. NASA is still planning exploration missions with the eventual destination of Mars and a new heavy lift launch vehicle is still required and will serve as the centerpiece of our nation s next exploration architecture s infrastructure. With an extensive launch vehicle database already developed on LOX/LH2 based heavy lift launch vehicles, ACO initiated a study to look at using a new high thrust (> 1.0 Mlb vacuum thrust) hydrocarbon engine as the primary main stage propulsion in such a launch vehicle.

  20. Shape memory alloy resetable spring lift for pedestrian protection

    Science.gov (United States)

    Barnes, Brian M.; Brei, Diann E.; Luntz, Jonathan E.; Strom, Kenneth; Browne, Alan L.; Johnson, Nancy

    2008-03-01

    Pedestrian protection has become an increasingly important aspect of automotive safety with new regulations taking effect around the world. Because it is increasingly difficult to meet these new regulations with traditional passive approaches, active lifts are being explored that increase the "crush zone" between the hood and rigid under-hood components as a means of mitigating the consequences of an impact with a non-occupant. Active lifts, however, are technically challenging because of the simultaneously high forces, stroke and quick timing resulting in most of the current devices being single use. This paper introduces the SMArt (Shape Memory Alloy ReseTable) Spring Lift, an automatically resetable and fully reusable device, which couples conventional standard compression springs to store the energy required for a hood lift, with Shape Memory Alloys actuators to achieve both an ultra high speed release of the spring and automatic reset of the system for multiple uses. Each of the four SMArt Device subsystems, lift, release, lower and reset/dissipate, are individually described. Two identical complete prototypes were fabricated and mounted at the rear corners of the hood, incorporated within a full-scale vehicle testbed at the SMARTT (Smart Material Advanced Research and Technology Transfer) lab at University of Michigan. Full operational cycle testing of a stationary vehicle in a laboratory setting confirms the ultrafast latch release, controlled lift profile, gravity lower to reposition the hood, and spring recompression via the ratchet engine successfully rearming the device for repeat cycles. While this is only a laboratory demonstration and extensive testing and development would be required for transition to a fielded product, this study does indicate that the SMArt Lift has promise as an alternative approach to pedestrian protection.

  1. Autoignited lifted flames of dimethyl ether in heated coflow air

    KAUST Repository

    Al-Noman, Saeed M.; Choi, Byung Chul; Chung, Suk-Ho

    2018-01-01

    Autoignited lifted flames of dimethyl ether (DME) in laminar nonpremixed jets with high-temperature coflow air have been studied experimentally. When the initial temperature was elevated to over 860 K, an autoignition occurred without requiring an external ignition source. A planar laser-induced fluorescence (PLIF) technique for formaldehyde (CH2O) visualized qualitatively the zone of low temperature kinetics in a premixed flame. Two flame configurations were investigated; (1) autoignited lifted flames with tribrachial edge having three distinct branches of a lean and a rich premixed flame wings with a trailing diffusion flame and (2) autoignited lifted flames with mild combustion when the fuel was highly diluted. For the autoignited tribrachial edge flames at critical autoignition conditions, exhibiting repetitive extinction and re-ignition phenomena near a blowout condition, the characteristic flow time (liftoff height scaled with jet velocity) was correlated with the square of the ignition delay time of the stoichiometric mixture. The liftoff heights were also correlated as a function of jet velocity times the square of ignition delay time. Formaldehydes were observed between the fuel nozzle and the lifted flame edge, emphasizing a low-temperature kinetics for autoignited lifted flames, while for a non-autoignited lifted flame, formaldehydes were observed near a thin luminous flame zone.For the autoignited lifted flames with mild combustion, especially at a high temperature, a unique non-monotonic liftoff height behavior was observed; decreasing and then increasing liftoff height with jet velocity. This behavior was similar to the binary mixture fuels of CH4/H2 and CO/H2 observed previously. A transient homogeneous autoignition analysis suggested that such decreasing behavior with jet velocity can be attributed to partial oxidation characteristics of DME in producing appreciable amounts of CH4/CO/H2 ahead of the edge flame region.

  2. A second-order shock-expansion method applicable to bodies of revolution near zero lift

    Science.gov (United States)

    1957-01-01

    A second-order shock-expansion method applicable to bodies of revolution is developed by the use of the predictions of the generalized shock-expansion method in combination with characteristics theory. Equations defining the zero-lift pressure distributions and the normal-force and pitching-moment derivatives are derived. Comparisons with experimental results show that the method is applicable at values of the similarity parameter, the ratio of free-stream Mach number to nose fineness ratio, from about 0.4 to 2.

  3. The hybrid assistive limb (HAL) for Care Support successfully reduced lumbar load in repetitive lifting movements.

    Science.gov (United States)

    Miura, Kousei; Kadone, Hideki; Koda, Masao; Abe, Tetsuya; Kumagai, Hiroshi; Nagashima, Katsuya; Mataki, Kentaro; Fujii, Kengo; Noguchi, Hiroshi; Funayama, Toru; Kawamoto, Hiroaki; Sankai, Yoshiyuki; Yamazaki, Masashi

    2018-05-03

    Work-related low back pain is a serious socioeconomic problem. This study examined whether HAL for Care Support, which is a newly developed wearable robot, would decrease lumbar fatigue and improve lifting performance during repetitive lifting movements. Eighteen healthy volunteers (11 men, 7 women) performed repetitive stoop lifting movements of a cardboard box weighing 12 kg as many times as possible. The first lifting trial was executed without HAL for Care Support, and the second was with it. We evaluated the VAS of lumbar fatigue as the lumbar load and the number of lifts and the lifting time as lifting performance. Without HAL for Care Support, the mean VAS of lumbar fatigue, the number of lifts and lifting time were 68 mm, 60 and 230 s; with HAL for Care Support, they were 51 mm, 87 and 332 s, respectively. Both lifting performance measures were significantly improved by using HAL for Care Support (Fig. 2). A power analysis showed that there was sufficient statistical power for the VAS of lumbar fatigue (0.99), the number of lifts (0.92), and lifting time (0.93). All participants performed their repetitive lifting trials safely. There were no adverse events caused by using HAL for Care Support. In conclusion, the HAL for Care Support can decrease lumbar load and improve the lifting performance during repetitive stoop lifting movements in healthy adults. Copyright © 2018. Published by Elsevier Ltd.

  4. Low-back loading in lifting two loads beside the body compared to lifting one load in front of the body

    NARCIS (Netherlands)

    Faber, G.S.; Kingma, I.; Bakker, A.J.; van Dieen, J.H.

    2009-01-01

    Low-back load during manual lifting is considered an important risk factor for the occurrence of low-back pain. Splitting a load, so it can be lifted beside the body (one load in each hand), instead of in front of the body, can be expected to reduce low-back load. Twelve healthy young men lifted 10

  5. Lifting Wing in Constructing Tall Buildings —Aerodynamic Testing

    Directory of Open Access Journals (Sweden)

    Ian Skelton

    2014-05-01

    Full Text Available This paper builds on previous research by the authors which determined the global state-of-the-art of constructing tall buildings by surveying the most active specialist tall building professionals around the globe. That research identified the effect of wind on tower cranes as a highly ranked, common critical issue in tall building construction. The research reported here presents a design for a “Lifting Wing,” a uniquely designed shroud which potentially allows the lifting of building materials by a tower crane in higher and more unstable wind conditions, thereby reducing delay on the programmed critical path of a tall building. Wind tunnel tests were undertaken to compare the aerodynamic performance of a scale model of a typical “brick-shaped” construction load (replicating a load profile most commonly lifted via a tower crane against the aerodynamic performance of the scale model of the Lifting Wing in a range of wind conditions. The data indicate that the Lifting Wing improves the aerodynamic performance by a factor of up to 50%.

  6. Numerical Study of Transition of an Annular Lift Fan Aircraft

    Directory of Open Access Journals (Sweden)

    Yun Jiang

    2016-09-01

    Full Text Available The present study aimed at studying the transition of annular lift fan aircraft through computational fluid dynamics (CFD simulations. The oscillations of lift and drag, the optimization for the figure of merit, and the characteristics of drag, yawing, rolling and pitching moments in transition are studied. The results show that a two-stage upper and lower fan lift system can generate oscillations of lift and drag in transition, while a single-stage inner and outer fan lift system can eliminate the oscillations. The characteristics of momentum drag of the single-stage fans in transition are similar to that of the two-stage fans, but with the peak of drag lowered from 0.63 to 0.4 of the aircraft weight. The strategy to start transition from a negative angle of attack −21° further reduces the peak of drag to 0.29 of the weight. The strategy also reduces the peak of pitching torque, which needs upward extra thrusts of 0.39 of the weight to eliminate. The peak of rolling moment in transition needs differential upward thrusts of 0.04 of the weight to eliminate. The requirements for extra thrusts in transition lead to a total thrust–weight ratio of 0.7, which makes the aircraft more efficient for high speed cruise flight (higher than 0.7 Ma.

  7. Toward a new nanoLIFT transfer process

    International Nuclear Information System (INIS)

    Mezel, C.; Hallo, L.; Breil, J.; Souquet, A.; Guillemot, F.; Bourgeade, A.; Hebert, D.; Saut, O.

    2010-01-01

    The Laser Induced Forward Transfer (LIFT) is a direct-write technique used to print biological materials such as living cells or molecules. During the LIFT process, the biomaterial to be printed is deposited on a target submitted to a nanosecond laser shot, and the ejecta are collected onto a receiving substrate. Despite the several advantages of this technique (control of the propelled quantity, no spoiling of the substrate), it remains difficult to be employed due to the high sensitivity of its control parameters. Recently, Duocastella published some experimental results which exhibit the real-time jet formation process, under conditions similar to those present in the LIFT process. In the first Section, a typical experimental setup for LIFT process is presented. Then, simulations of Duocastella's and Guillemot's experiments are carried out to model the jet formation in water when irradiated by an ultraviolet nanosecond laser pulse. The 2D axisymmetric hydrodynamic code CHIC (Code d'Hydrodynamique et d'Implosion du CELIA) is used for these simulations with included equations of state (EOS) to take into account the behavior of water under standard conditions. Finally, an improvement of the LIFT technique which consists in using femtosecond lasers instead of nanosecond ones, is presented. It would allow to process smaller bioelements and to control the jet diameter, as it is directly related to the laser beam waist.

  8. A Simple Method for High-Lift Propeller Conceptual Design

    Science.gov (United States)

    Patterson, Michael; Borer, Nick; German, Brian

    2016-01-01

    In this paper, we present a simple method for designing propellers that are placed upstream of the leading edge of a wing in order to augment lift. Because the primary purpose of these "high-lift propellers" is to increase lift rather than produce thrust, these props are best viewed as a form of high-lift device; consequently, they should be designed differently than traditional propellers. We present a theory that describes how these props can be designed to provide a relatively uniform axial velocity increase, which is hypothesized to be advantageous for lift augmentation based on a literature survey. Computational modeling indicates that such propellers can generate the same average induced axial velocity while consuming less power and producing less thrust than conventional propeller designs. For an example problem based on specifications for NASA's Scalable Convergent Electric Propulsion Technology and Operations Research (SCEPTOR) flight demonstrator, a propeller designed with the new method requires approximately 15% less power and produces approximately 11% less thrust than one designed for minimum induced loss. Higher-order modeling and/or wind tunnel testing are needed to verify the predicted performance.

  9. Advances in Engineering Software for Lift Transportation Systems

    Science.gov (United States)

    Kazakoff, Alexander Borisoff

    2012-03-01

    In this paper an attempt is performed at computer modelling of ropeway ski lift systems. The logic in these systems is based on a travel form between the two terminals, which operates with high capacity cabins, chairs, gondolas or draw-bars. Computer codes AUTOCAD, MATLAB and Compaq-Visual Fortran - version 6.6 are used in the computer modelling. The rope systems computer modelling is organized in two stages in this paper. The first stage is organization of the ground relief profile and a design of the lift system as a whole, according to the terrain profile and the climatic and atmospheric conditions. The ground profile is prepared by the geodesists and is presented in an AUTOCAD view. The next step is the design of the lift itself which is performed by programmes using the computer code MATLAB. The second stage of the computer modelling is performed after the optimization of the co-ordinates and the lift profile using the computer code MATLAB. Then the co-ordinates and the parameters are inserted into a program written in Compaq Visual Fortran - version 6.6., which calculates 171 lift parameters, organized in 42 tables. The objective of the work presented in this paper is an attempt at computer modelling of the design and parameters derivation of the rope way systems and their computer variation and optimization.

  10. Bilayer lift-off process for aluminum metallization

    Science.gov (United States)

    Wilson, Thomas E.; Korolev, Konstantin A.; Crow, Nathaniel A.

    2015-01-01

    Recently published reports in the literature for bilayer lift-off processes have described recipes for the patterning of metals that have recommended metal-ion-free developers, which do etch aluminum. We report the first measurement of the dissolution rate of a commercial lift-off resist (LOR) in a sodium-based buffered commercial developer that does not etch aluminum. We describe a reliable lift-off recipe that is safe for multiple process steps in patterning thin (recipe consists of an acid cleaning of the substrate, the bilayer (positive photoresist/LOR) deposition and development, the sputtering of the aluminum film along with a palladium capping layer and finally, the lift-off of the metal film by immersion in the LOR solvent. The insertion into the recipe of postexposure and sequential develop-bake-develop process steps are necessary for an acceptable undercut. Our recipe also eliminates any need for accompanying sonication during lift-off that could lead to delamination of the metal pattern from the substrate. Fine patterns were achieved for both 100-nm-thick granular aluminum/palladium bilayer bolometers and 500-nm-thick aluminum gratings with 6-μm lines and 4-μm spaces.

  11. Performance and Vibration Analyses of Lift-Offset Helicopters

    Directory of Open Access Journals (Sweden)

    Jeong-In Go

    2017-01-01

    Full Text Available A validation study on the performance and vibration analyses of the XH-59A compound helicopter is conducted to establish techniques for the comprehensive analysis of lift-offset compound helicopters. This study considers the XH-59A lift-offset compound helicopter using a rigid coaxial rotor system as a verification model. CAMRAD II (Comprehensive Analytical Method of Rotorcraft Aerodynamics and Dynamics II, a comprehensive analysis code, is used as a tool for the performance, vibration, and loads analyses. A general free wake model, which is a more sophisticated wake model than other wake models, is used to obtain good results for the comprehensive analysis. Performance analyses of the XH-59A helicopter with and without auxiliary propulsion are conducted in various flight conditions. In addition, vibration analyses of the XH-59A compound helicopter configuration are conducted in the forward flight condition. The present comprehensive analysis results are in good agreement with the flight test and previous analyses. Therefore, techniques for the comprehensive analysis of lift-offset compound helicopters are appropriately established. Furthermore, the rotor lifts are calculated for the XH-59A lift-offset compound helicopter in the forward flight condition to investigate the airloads characteristics of the ABC™ (Advancing Blade Concept rotor.

  12. Reduction of Dynamic Loads in Mine Lifting Installations

    Science.gov (United States)

    Kuznetsov, N. K.; Eliseev, S. V.; Perelygina, A. Yu

    2018-01-01

    Article is devoted to a problem of decrease in the dynamic loadings arising in transitional operating modes of the mine lifting installations leading to heavy oscillating motions of lifting vessels and decrease in efficiency and reliability of work. The known methods and means of decrease in dynamic loadings and oscillating motions of the similar equipment are analysed. It is shown that an approach based on the concept of the inverse problems of dynamics can be effective method of the solution of this problem. The article describes the design model of a one-ended lifting installation in the form of a two-mass oscillation system, in which the inertial elements are the mass of the lifting vessel and the reduced mass of the engine, reducer, drum and pulley. The simplified mathematical model of this system and results of an efficiency research of an active way of reduction of dynamic loadings of lifting installation on the basis of the concept of the inverse problems of dynamics are given.

  13. The Cumulative Lifting Index (CULI) for the Revised NIOSH Lifting Equation: Quantifying Risk for Workers With Job Rotation.

    Science.gov (United States)

    Garg, Arun; Kapellusch, Jay M

    2016-08-01

    The objectives were to: (a) develop a continuous frequency multiplier (FM) for the Revised NIOSH Lifting Equation (RNLE) as a function of lifting frequency and duration of a lifting task, and (b) describe the Cumulative Lifting Index (CULI), a methodology for estimating physical exposure to workers with job rotation. The existing FM for the RNLE (FME) does not differentiate between task duration >2 hr and <8 hr, which makes quantifying physical exposure to workers with job rotation difficult and presents challenges to job designers. Using the existing FMs for 1, 2, and 8 hr of task durations, we developed a continuous FM (FMP) that extends to 12 hr per day. We simulated 157,500 jobs consisting of two tasks each and, using different combinations of Frequency Independent Lifting Index, lifting frequency and duration of lifting. Biomechanical stresses were estimated using the CULI, time-weighted average (TWA), and peak exposure. The median difference between FME and FMP was ±1% (range: 0%-15%). Compared to CULI, TWA underestimated risk of low-back pain (LBP) for 18% to 30% of jobs, and peak exposure for an assumed 8-hr work shift overestimated risk of LBP for 20% to 25% of jobs. Peak task exposure showed 90% agreement with CULI but ignored one of two tasks. The CULI partially addressed the underestimation of physical exposure using the TWA approach and overestimation of exposure using the peak-exposure approach. The proposed FM and CULI may provide more accurate physical exposure estimates, and therefore estimated risk of LBP, for workers with job rotation. © 2016, Human Factors and Ergonomics Society.

  14. Maximum acceptable weight of lift reflects peak lumbosacral extension moments in a functional capacity evaluation test using free style, stoop and squat lifting.

    Science.gov (United States)

    Kuijer, P P F M; van Oostrom, S H; Duijzer, K; van Dieën, J H

    2012-01-01

    It is unclear whether the maximum acceptable weight of lift (MAWL), a common psychophysical method, reflects joint kinetics when different lifting techniques are employed. In a within-participants study (n = 12), participants performed three lifting techniques--free style, stoop and squat lifting from knee to waist level--using the same dynamic functional capacity evaluation lifting test to assess MAWL and to calculate low back and knee kinetics. We assessed which knee and back kinetic parameters increased with the load mass lifted, and whether the magnitudes of the kinetic parameters were consistent across techniques when lifting MAWL. MAWL was significantly different between techniques (p = 0.03). The peak lumbosacral extension moment met both criteria: it had the highest association with the load masses lifted (r > 0.9) and was most consistent between the three techniques when lifting MAWL (ICC = 0.87). In conclusion, MAWL reflects the lumbosacral extension moment across free style, stoop and squat lifting in healthy young males, but the relation between the load mass lifted and lumbosacral extension moment is different between techniques. Tests of maximum acceptable weight of lift (MAWL) from knee to waist height are used to assess work capacity of individuals with low-back disorders. This article shows that the MAWL reflects the lumbosacral extension moment across free style, stoop and squat lifting in healthy young males, but the relation between the load mass lifted and lumbosacral extension moment is different between techniques. This suggests that standardisation of lifting technique used in tests of the MAWL would be indicated if the aim is to assess the capacity of the low back.

  15. Lifting and protecting residential structures from subsidence damage using airbags

    International Nuclear Information System (INIS)

    Triplett, T.L.; Bennett, R.M.

    1998-01-01

    Conventional practice in protecting residential structures from subsidence damage concentrates on saving the superstructure. The foundation is sacrificed, even though it represents the structural component with the greatest replacement cost. In this study, airbags were used to lift a 20 ft x 30 ft structure to test their ability to protect both the foundation and superstructure from ground settlement. Two contiguous sides of the test foundation were unreinforced, and the other two contiguous sides incorporated footing and wall reinforcement. The airbags successfully lifted the structure without causing damage, even on the unreinforced sides. This paper gives a procedure for determining airbag spacing, and describes installation and operation techniques of the airbags. The paper then focuses on the performance of the airbags in lifting the structure, and shows that airbags can preserve existing foundations during subsidence movements

  16. Lift 2013⎜February 6 to 8

    CERN Multimedia

    2013-01-01

    The Lift Conference returns to the Centre International de Conférence de Genève, with speakers ranging from a science fiction author to a cognitive neuroscience researcher. As one of the foremost talk events of Europe, Lift 2013 seeks to discover new trends and turn them into opportunities.   The three-day conference is designed to engage and arouse intellectual curiosity by exploring the business and social implications of technological innovation. This year’s schedule also includes discussion of the political implications of technology and the impact of the online market on the future of economy. Alongside talks, workshops will be held on a wide range of topics, including the relationship between entrepreneur and investor, designs that influence social behaviour, and how ordinary people are changing the urban space. Lift 2013 also seeks to promote new business ventures and will award prizes to the start-up company that succeeds in convincing the audience an...

  17. Experimental and simulated control of lift using trailing edge devices

    Science.gov (United States)

    Cooperman, A.; Blaylock, M.; van Dam, C. P.

    2014-12-01

    Two active aerodynamic load control (AALC) devices coupled with a control algorithm are shown to decrease the change in lift force experienced by an airfoil during a change in freestream velocity. Microtabs are small (1% chord) surfaces deployed perpendicular to an airfoil, while microjets are pneumatic jets with flow perpendicular to the surface of the airfoil near the trailing edge. Both devices are capable of producing a rapid change in an airfoil's lift coefficient. A control algorithm for microtabs has been tested in a wind tunnel using a modified S819 airfoil, and a microjet control algorithm has been simulated for a NACA 0012 airfoil using OVERFLOW. In both cases, the AALC devices have shown the ability to mitigate the changes in lift during a gust.

  18. Experimental and simulated control of lift using trailing edge devices

    International Nuclear Information System (INIS)

    Cooperman, A; Blaylock, M; Van Dam, C P

    2014-01-01

    Two active aerodynamic load control (AALC) devices coupled with a control algorithm are shown to decrease the change in lift force experienced by an airfoil during a change in freestream velocity. Microtabs are small (1% chord) surfaces deployed perpendicular to an airfoil, while microjets are pneumatic jets with flow perpendicular to the surface of the airfoil near the trailing edge. Both devices are capable of producing a rapid change in an airfoil's lift coefficient. A control algorithm for microtabs has been tested in a wind tunnel using a modified S819 airfoil, and a microjet control algorithm has been simulated for a NACA 0012 airfoil using OVERFLOW. In both cases, the AALC devices have shown the ability to mitigate the changes in lift during a gust

  19. Propeller performance analysis using lifting line theory

    OpenAIRE

    Flood, Kevin M.

    2009-01-01

    CIVINS (Civilian Institutions) Thesis document Approved for public release ; distribution is unlimited Propellers are typically optimized to provide the maximum thrust for the minimum torque at a specific number of revolutions per minute (RPM) at a particular ship speed. This process allows ships to efficiently travel at their design speed. However, it is useful to know how the propeller performs during off-design conditions. This is especially true for naval warships whose missions req...

  20. Large Scale Composite Manufacturing for Heavy Lift Launch Vehicles

    Science.gov (United States)

    Stavana, Jacob; Cohen, Leslie J.; Houseal, Keth; Pelham, Larry; Lort, Richard; Zimmerman, Thomas; Sutter, James; Western, Mike; Harper, Robert; Stuart, Michael

    2012-01-01

    Risk reduction for the large scale composite manufacturing is an important goal to produce light weight components for heavy lift launch vehicles. NASA and an industry team successfully employed a building block approach using low-cost Automated Tape Layup (ATL) of autoclave and Out-of-Autoclave (OoA) prepregs. Several large, curved sandwich panels were fabricated at HITCO Carbon Composites. The aluminum honeycomb core sandwich panels are segments of a 1/16th arc from a 10 meter cylindrical barrel. Lessons learned highlight the manufacturing challenges required to produce light weight composite structures such as fairings for heavy lift launch vehicles.

  1. Numerical study of aerodynamic effects on road vehicles lifting surfaces

    Science.gov (United States)

    Cernat, Mihail Victor; Cernat Bobonea, Andreea

    2017-01-01

    The aerodynamic performance analysis of road vehicles depends on the study of engine intake and cooling flow, internal ventilation, tire cooling, and overall external flow as the motion of air around a moving vehicle affects all of its components in one form or another. Due to the complex geometry of these, the aerodynamic interaction between the various body components is significant, resulting in vortex flow and lifting surface shapes. The present study, however focuses on the effects of external aerodynamics only, and in particular on the flow over the lifting surfaces of a common compact car, designed especially for this study.

  2. Lift of a rotating circular cylinder in unsteady flows

    DEFF Research Database (Denmark)

    Carstensen, Stefan; Mandviwalla, Xerxes; Vita, Luca

    2012-01-01

    A cylinder rotating in steady current experiences a lift known as the Magnus effect. In the present study the effect of waves on the Magnus effect has been investigated. This situation is experienced with the novel floating offshore vertical axis wind turbine (VAWT) concept called the DEEPWIND...... concept, which incorporates a rotating spar buoy and thereby utilizes seawater as a roller-bearing. The a priori assumption and the results suggest that the lift in waves, to a first approximation, may be represented by a formulation similar to the well-known Morison formulation. The force coefficients...

  3. New constructions of twistor lifts for harmonic maps

    DEFF Research Database (Denmark)

    Svensson, Martin; C. Wood, John

    2014-01-01

    We show that given a harmonic map \\varphi from a Riemann surface into a classical simply connected compact inner symmetric space, there is a J_2-holomorphic twistor lift of \\varphi (or its negative) if and only if it is nilconformal. In the case of harmonic maps of finite uniton number, we give...... algebraic formulae in terms of holomorphic data which describes their extended solutions. In particular, this gives explicit formulae for the twistor lifts of all harmonic maps of finite uniton number from a surface to the above symmetric spaces....

  4. A New Perceptual Mapping Model Using Lifting Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Taha TahaBasheer

    2017-01-01

    Full Text Available Perceptual mappingapproaches have been widely used in visual information processing in multimedia and internet of things (IOT applications. Accumulative Lifting Difference (ALD is proposed in this paper as texture mapping model based on low-complexity lifting wavelet transform, and combined with luminance masking for creating an efficient perceptual mapping model to estimate Just Noticeable Distortion (JND in digital images. In addition to low complexity operations, experiments results show that the proposed modelcan tolerate much more JND noise than models proposed before

  5. Project, Aerodynamic, Thermal and Ballistic Analysis of a Lifting-Body Reentry Vehicle

    Directory of Open Access Journals (Sweden)

    A. N. Eliseev

    2015-01-01

    Full Text Available The objective of this article is to assess the prospects for an increasingly maneuverable reentry vehicle (RV of class "lifting body". In this regard, a project aerodynamic thermal and ballistic analysis has been conducted and the results have been compared with some well-known projects of the RV of the same class, made both in our country and abroad.The project analysis begins with finding a position of the "lifting body" vehicle in the classification system. Said classification distribution allows correct formulation of requirements for the conceptual structure of an aerospace vehicle at the initial stage of design in terms of system positions, since just the initial phase of the design often determines the success of the whole program.Then the paper compares design characteristics of the RV of class "lifting body" with vehicles such as X-15 rocket plane, the orbiter "Space Shuttle», M2-F2, HL-10, SV-5, and NASP "Hermes". It also gives a comparative estimate of the "lifting body" RV mass in a wide range of dimensions. The paper shows the sustainability of various landing complexes with reference to the Russian experience in developing the RV " Soyuz", and the conditions for using the vehicles of class "lifting body" in space programs.The aerodynamic analysis uses method for the approximate Newtonian theory to calculate aerodynamic characteristics of the perspective RV of class "lifting body" in the hypersonic descent phase. To obtain the desired aerodynamic performance and reduce balancing weight is contemplated a possibility to provide balance by introducing additional boards. The ballistic analysis considers four modes of descent:1. zero roll descent;2. maximum cross-range descent without restriction;3. maximum cross-range descent with restriction of maximum overload and maximum temperature;4. ballistic descent.To calculate the RV ballistic characteristics a system of equations of the vehicle motion in the atmosphere is used. The vehicle

  6. Lift and Drag on Cylinder of Octagonal Cross-Section in a Turbulent Stream

    Directory of Open Access Journals (Sweden)

    Md. Jomir Hossain

    2013-12-01

    Full Text Available An experimental investigation of surface static pressure distributions on octagonal cylinder in uniform and turbulent flows was carried out. The study was performed on both the single cylinder and the group of two cylinders, two cylinders were used, one was at the upstream side, and the other was at the downstream side of the flow. They were placed centrally along the flow direction. The inter-spacing space between the two cylinders was varied at 1D, 2D, 3D, 4D, 5D, 6D, 7D and 8D, where D is the width of the cylinder across the flow direction. The pressure coefficients were calculated from the measured values of the surface static pressure distribution on the cylinder. Then the drag and lift coefficients were obtained from the pressure coefficients by the numerical integration method. It was observed that at various angles of attack, the values of the lift coefficients and drag coefficients were insignificant compared to those for a sharp-edged square cylinder. The strength of the vortex shedding was shown to be reduced as the intensity of the incident turbulence was increased. Measurements of drag at various angles of attack (0° to 40° showed that with increase in turbulence level the minimum drag occurred at smaller values of angle of attack.

  7. Optimization of a variable-stiffness skin for morphing high-lift devices

    International Nuclear Information System (INIS)

    Thuwis, G A A; Abdalla, M M; Gürdal, Z

    2010-01-01

    One of the possibilities for the next generation of smart high-lift devices is to use a seamless morphing structure. A passive composite variable-stiffness skin as a solution to the dilemma of designing the structure to have high enough stiffness to withstand aerodynamic loading and low stiffness to enable morphing is proposed. The variable-stiffness skin is achieved by allowing for a spatial fibre angle and skin thickness variation on a morphing high-lift system. The stiffness distribution is tailored to influence the deformation of the structure beneficially. To design a realistic stiffness distribution, it is important to take aerodynamic and actuation loads into account during the optimization. A two-dimensional aero-servo-elastic framework is created for this purpose. Skin optimization is performed using a gradient-based optimizer, where sensitivity information is found through application of the adjoint method. The implementation of the aero-servo-elastic environment is addressed and initial optimization results presented. The results indicate that a variable-stiffness skin increases the design space. Moreover, the importance of taking the change in aerodynamic loads due to morphing skin deformation into account during optimization is demonstrated

  8. Assembly and lifting of Pearl-Chain arches

    DEFF Research Database (Denmark)

    Halding, Philip Skov; Hertz, Kristian Dahl; Viebæk, N.E.

    2015-01-01

    Pearl-Chain arches were invented at the Technical University of Denmark in cooporation with the company Abeo A/S. The system uses specially designed, pre-fabricated concrete elements that are post-tensioned together into an arch shape, which is then lifted into place. The arches can be used both ...

  9. Object size effects on initial lifting forces under microgravity conditions

    NARCIS (Netherlands)

    Kingma, I.; Savelsbergh, G.J.P.; Toussaint, H.M.

    1999-01-01

    Individuals usually report for two objects of equal mass but different volume that the larger object feels lighter. This so-called size-weight illusion has been investigated for more than a century. The illusion is accompanied by increased forces, used to lift the larger object, resulting in a

  10. The new Toyota variable valve timing and lift system

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, K.; Fuwa, N.; Yoshihara, Y. [Toyota Motor Corporation (Japan); Hori, K. [Toyota Boshoku Corporation (Japan)

    2007-07-01

    A continuously variable valve timing (duration and phase) and lift system was developed. This system was applied to the valvetrain of a new 2.0L L4 engine (3ZRFAE) for the Japanese market. The system has rocker arms, which allow continuously variable timing and lift, situated between a conventional roller-rocker arm and the camshaft, an electromotor actuator to drive it and a phase mechanism for intake and exhaust camshafts (Dual VVT-i). The rocking center of the rocker arm is stationary, and the axial linear motion of a helical spline changes the initial phase of the rocker arm which varies the timing and lift. The linear motion mechanism uses an original planetary roller screw and is driven by a brushless motor with a built-in electric control unit. Since the rocking center and the linear motion helical spline center coincide, a compact cylinder head design was possible, and the cylinder head is a common design with a conventional engine. Since the ECU controls intake valve duration and timing, a fuel economy gain of maximum 10% (depending on driving condition) is obtained by reducing light to medium load pumping losses. Also intake efficiency was maximized throughout the speed range, resulting in a power gain of 10%. Further, HC emissions were reduced due to increased air speed at low valve lift. (orig.)

  11. Ecosystem Food Web Lift-The-Flap Pages

    Science.gov (United States)

    Atwood-Blaine, Dana; Rule, Audrey C.; Morgan, Hannah

    2016-01-01

    In the lesson on which this practical article is based, third grade students constructed a "lift-the-flap" page to explore food webs on the prairie. The moveable papercraft focused student attention on prairie animals' external structures and how the inferred functions of those structures could support further inferences about the…

  12. Lifting to cluster-tilting objects in higher cluster categories

    OpenAIRE

    Liu, Pin

    2008-01-01

    In this note, we consider the $d$-cluster-tilted algebras, the endomorphism algebras of $d$-cluster-tilting objects in $d$-cluster categories. We show that a tilting module over such an algebra lifts to a $d$-cluster-tilting object in this $d$-cluster category.

  13. Anticipatory postural adjustments in the back and leg lift

    NARCIS (Netherlands)

    Toussaint, H.M.; Commissaris, D.A.C.M.; Beek, P.J.

    1997-01-01

    This study examined anticipatory postural adjustments in a dynamic multi-joint action in which a relatively fast voluntary movement is being executed while balance is maintained in the field of gravity. In a bi-manual whole body lifting task, the pickup of the load induces a forward shift in the

  14. Customized lifting multiwavelet packet information entropy for equipment condition identification

    International Nuclear Information System (INIS)

    Chen, Jinglong; Zi, Yanyang; He, Zhengjia; Chen, Xuefeng; Zuo, Ming J; Yuan, Jing

    2013-01-01

    Condition identification of mechanical equipment from vibration measurement data is significant to avoid economic loss caused by unscheduled breakdowns and catastrophic accidents. However, this task still faces challenges due to the complexity of equipment and the harsh environment. This paper provides a possibility for equipment condition identification by proposing a method called customized lifting multiwavelet packet information entropy. Benefiting from the properties of multi-resolution analysis and multiple wavelet basis functions, the multiwavelet method has advantages in characterizing non-stationary vibration signals. In order to realize the accurate detection and identification of the condition features, a customized lifting multiwavelet packet is constructed via a multiwavelet lifting scheme. Then the vibration signal from the mechanical equipment is processed by the customized lifting multiwavelet packet transform. The relative energy in each frequency band of the multiwavelet packet transform coefficients that equals a percentage of the whole signal energy is taken as the probability. The normalized information entropy is obtained based on the relative energy to describe the condition of a mechanical system. The proposed method is applied to the condition identification of a rolling mill and a demountable disk–drum aero-engine. The results support the feasibility of the proposed method in equipment condition identification. (paper)

  15. Back muscle strength, lifting, and stooped working postures.

    Science.gov (United States)

    Poulsen, E; Jørgensen, K

    1971-09-01

    When lifting loads and working in a forward stooped position, the muscles of the back rather than the ligaments and bony structures of the spine should overcome the gravitational forces. Formulae, based on measurements of back muscle strength, for prediction of maximal loads to be lifted, and for the ability to sustain work in a stooped position, have been worked out and tested in practical situations. From tests with 50 male and female subjects the simplest prediction formulae for maximum loads were: max. load = 1.10 x isometric back muscle strength for men; and max. load = 0.95 x isometric back muscle strength - 8 kg for women. Some standard values for maximum lifts and permissible single and repeated lifts have been calculated for men and women separately and are given in Table 1. From tests with 65 rehabilitees it was found that the maximum isometric strength of the back muscles measured at shoulder height should exceed 2/3 of the body weight, if fatigue and/or pain in the back muscles is to be avoided during work in a standing stooped position.

  16. Drag power kite with very high lift coefficient

    NARCIS (Netherlands)

    Bauer, F.; Kennel, R.M.; Hackl, C.M.; Campagnolo, F.; Patt, M.; Schmehl, R.

    2018-01-01

    As an alternative to conventional wind turbines, this study considered kites with onboard wind turbines driven by a high airspeed due to crosswind flight (“drag power”). The hypothesis of this study was, that if the kite's lift coefficient is maximized, then the power, energy yield, allowed costs

  17. Creating drag and lift curves from soccer trajectories

    Science.gov (United States)

    Goff, John Eric; Kelley, John; Hobson, Chad M.; Seo, Kazuya; Asai, Takeshi; Choppin, S. B.

    2017-07-01

    Trajectory analysis is an alternative to using wind tunnels to measure a soccer ball’s aerodynamic properties. It has advantages over wind tunnel testing such as being more representative of game play. However, previous work has not presented a method that produces complete, speed-dependent drag and lift coefficients. Four high-speed cameras in stereo-calibrated pairs were used to measure the spatial co-ordinates for 29 separate soccer trajectories. Those trajectories span a range of launch speeds from 9.3 to 29.9 m s-1. That range encompasses low-speed laminar flow of air over a soccer ball, through the drag crises where air flow is both laminar and turbulent, and up to high-speed turbulent air flow. Results from trajectory analysis were combined to give speed-dependent drag and lift coefficient curves for the entire range of speeds found in the 29 trajectories. The average root mean square error between the measured and modelled trajectory was 0.028 m horizontally and 0.034 m vertically. The drag and lift crises can be observed in the plots of drag and lift coefficients respectively.

  18. Outcomes of polydioxanone knotless thread lifting for facial rejuvenation.

    Science.gov (United States)

    Suh, Dong Hye; Jang, Hee Won; Lee, Sang Jun; Lee, Won Seok; Ryu, Hwa Jung

    2015-06-01

    Thread lifting is a minimally invasive technique for facial rejuvenation. Various devices for thread lifting using polydioxanone (PDO) are popular in aesthetic clinics in Korea, but there have been a few studies regarding its use. To describe PDO thread and techniques adopted to counteract the descent and laxity of the face. A retrospective chart review was conducted over a 24-month period. A total of 31 thread lifting procedures were performed. On each side, 5 bidirectional cog threads were used in the procedure for the flabby skin of the nasolabial folds. And, the procedure was performed on the marionette line using 2 twin threads. In most patients (87%), the results obtained were considered satisfactory. Consensus ratings by 2 physicians found that objective outcomes were divided among "excellent," "good," "fair," and "poor." Texture wise, the outcome ratings were 13 as excellent and 9 as good. Lifting wise, ratings were 11 as excellent and 6 as good. The incidence of complications was low and not serious. Facial rejuvenation using PDO thread is a safe and effective procedure associated with only minor complications when performed on patients with modest face sagging, fine wrinkles, and marked facial pores.

  19. Functional Commutant Lifting and Interpolation on Generalized Analytic Polyhedra

    Czech Academy of Sciences Publication Activity Database

    Ambrozie, Calin-Grigore

    2008-01-01

    Roč. 34, č. 2 (2008), s. 519-543 ISSN 0362-1588 R&D Projects: GA ČR(CZ) GA201/06/0128 Institutional research plan: CEZ:AV0Z10190503 Keywords : intertwining lifting * interpolation * analytic functions Subject RIV: BA - General Mathematics Impact factor: 0.327, year: 2008

  20. 14 CFR 25.345 - High lift devices.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false High lift devices. 25.345 Section 25.345... devices. (a) If wing flaps are to be used during takeoff, approach, or landing, at the design flap speeds.... The analysis must take into account the unsteady aerodynamic characteristics and rigid body motions of...

  1. Prostatic urethral lift vs transurethral resection of the prostate

    DEFF Research Database (Denmark)

    Gratzke, Christian; Barber, Neil; Speakman, Mark J

    2017-01-01

    OBJECTIVES: To compare prostatic urethral lift (PUL) with transurethral resection of the prostate (TURP) with regard to symptoms, recovery experience, sexual function, continence, safety, quality of life, sleep and overall patient perception. PATIENTS AND METHODS: A total of 80 patients with lower...

  2. Lifted Java: A Minimal Calculus for Translation Polymorphism

    DEFF Research Database (Denmark)

    Ingesman, Matthias Diehn; Ernst, Erik

    2012-01-01

    To support roles and similar notions involving multiple views on an object, languages like Object Teams and CaesarJ include mechanisms known as lifting and lowering. These mechanisms connect pairs of objects of otherwise unrelated types, and enable programmers to consider such a pair almost...

  3. Accelerating wavelet lifting on graphics hardware using CUDA

    NARCIS (Netherlands)

    Laan, van der W.J.; Roerdink, J.B.T.M.; Jalba, A.C.

    2011-01-01

    The Discrete Wavelet Transform (DWT) has a wide range of applications from signal processing to video and image compression. We show that this transform, by means of the lifting scheme, can be performed in a memory and computation-efficient way on modern, programmable GPUs, which can be regarded as

  4. Accelerating Wavelet Lifting on Graphics Hardware Using CUDA

    NARCIS (Netherlands)

    Laan, Wladimir J. van der; Jalba, Andrei C.; Roerdink, Jos B.T.M.

    The Discrete Wavelet Transform (DWT) has a wide range of applications from signal processing to video and image compression. We show that this transform, by means of the lifting scheme, can be performed in a memory and computation-efficient way on modern, programmable GPUs, which can be regarded as

  5. Feasibility study of two-lift concrete paving : technical report.

    Science.gov (United States)

    2014-04-01

    Two-lift concrete paving (2LCP) involves placing two layers of concrete (wet-on-wet) instead of a single : homogeneous layer, as is typically done in the United States. 2LCP offers the opportunity to optimize the use of local : aggregates, recycled m...

  6. Assessment of the sinus lift operation by magnetic resonance imaging.

    Science.gov (United States)

    Senel, Figen Cizmeci; Duran, Serpil; Icten, Onur; Izbudak, Izlem; Cizmeci, Fulya

    2006-12-01

    Vertical bone loss in edentulous maxillary alveolar processes may necessitate a sinus lift before the placement of dental implants. We have measured and assessed maxillary sinuses meticulously before the operation and evaluated the postoperative results of the operation with magnetic resonance imaging (MRI). Thirteen edentulous maxillary regions in eight patients were included in the study. The patients were examined 1 week before and 3 months after the sinus lift operations using a 1.5 T superconductive MR imager that gave oblique sagittal T2-weighted images with slices 2 mm thick without a gap. The images that were obtained 3 months after the sinus lift operations confirmed that vertical height had increased. We obtained high quality images without any artefacts during a short examination period with a high-resolution scanner. The results showed that it is possible to assess the maxillary sinus before the sinus lift and to evaluate the postoperative results using MRI accurately in three dimensions without the risk of radiation. This makes MRI a suitable alternative to computed tomography (CT).

  7. Properties of lift-off structured high Tc microbridges

    NARCIS (Netherlands)

    Hauser, B.; Klopman, B.; Blank, David H.A.; Rogalla, Horst

    1989-01-01

    Microbridges and DC SQUIDs (superconducting quantum interference devices) were fabricated, using a lift-off technique, from RF sputtered YBaCuO films on MgO single-crystal substrates. Microwave measurements at 9 GHz on microbridges and the magnetic-field dependence of their critical current reveal

  8. SAGD gas lift completions and optimization : a field case study at Surmont

    Energy Technology Data Exchange (ETDEWEB)

    Handfield, T.C.; Nations, T.; Noonan, S.G. [ConocoPhillips Co., Houston, TX (United States)

    2008-10-15

    Gas lift completions for steam assisted gravity drainage (SAGD) producers are unique. Because of the extreme temperatures of the downhole environment, conventional gas lift valves and mandrels with a packer completion cannot be used. Most gas lifts enter the production stream downhole through open-ended tubing or nozzles, which if not properly sized could result in operational issues, such as fluid/gas slugging and pressure instabilities which negatively effect the overall lift efficiency. ConocoPhillips performed a study in 2006 to design a gas lift system for the Surmont SAGD development that would allow better control of lift gas into the production string. The wells completed with gas lift were placed on production in 2007. This paper discussed the data collection effort and analysis completed to determine the efficiency of the two types of gas lift nozzles used in the completions. It also presented the methodology for optimization of SAGD gas lift systems and recommendations for future improvement. Background information on the Surmont oil sands project, located southeast of Fort McMurray in the Athabasca oil sands was included along with a historical perspective of the SAGD Surmont gas lift experience followed by a discussion of the Surmont initial gas lift design. Last, the paper discussed the Surmont gas lift start-up and optimization. It was concluded that installation of backcheck valves in coil tubing used for gas lift may mitigate plugging issues on initial start-up and following periods of shut-down. 5 refs., 10 figs.

  9. Optimisation of amplitude distribution of magnetic Barkhausen noise

    Science.gov (United States)

    Pal'a, Jozef; Jančárik, Vladimír

    2017-09-01

    The magnetic Barkhausen noise (MBN) measurement method is a widely used non-destructive evaluation technique used for inspection of ferromagnetic materials. Besides other influences, the excitation yoke lift-off is a significant issue of this method deteriorating the measurement accuracy. In this paper, the lift-off effect is analysed mainly on grain oriented Fe-3%Si steel subjected to various heat treatment conditions. Based on investigation of relationship between the amplitude distribution of MBN and lift-off, an approach to suppress the lift-off effect is proposed. Proposed approach utilizes the digital feedback optimising the measurement based on the amplitude distribution of MBN. The results demonstrated that the approach can highly suppress the lift-off effect up to 2 mm.

  10. Face-Lift Satisfaction Using the FACE-Q.

    Science.gov (United States)

    Sinno, Sammy; Schwitzer, Jonathan; Anzai, Lavinia; Thorne, Charles H

    2015-08-01

    Face lifting is one of the most common operative procedures for facial aging and perhaps the procedure most synonymous with plastic surgery in the minds of the lay public, but no verifiable documentation of patient satisfaction exists in the literature. This study is the first to examine face-lift outcomes and patient satisfaction using a validated questionnaire. One hundred five patients undergoing a face lift performed by the senior author (C.H.T.) using a high, extended-superficial musculoaponeurotic system with submental platysma approximation technique were asked to complete anonymously the FACE-Q by e-mail. FACE-Q scores were assessed for each domain (range, 0 to 100), with higher scores indicating greater satisfaction with appearance or superior quality of life. Fifty-three patients completed the FACE-Q (50.5 percent response rate). Patients demonstrated high satisfaction with facial appearance (mean ± SD, 80.7 ± 22.3), and quality of life, including social confidence (90.4 ± 16.6), psychological well-being (92.8 ± 14.3), and early life impact (92.2 ± 16.4). Patients also reported extremely high satisfaction with their decision to undergo face lifting (90.5 ± 15.9). On average, patients felt they appeared 6.9 years younger than their actual age. Patients were most satisfied with the appearance of their nasolabial folds (86.2 ± 18.5), cheeks (86.1 ± 25.4), and lower face/jawline (86.0 ± 20.6), compared with their necks (78.1 ± 25.6) and area under the chin (67.9 ± 32.3). Patients who responded in this study were extremely satisfied with their decision to undergo face lifting and the outcomes and quality of life following the procedure.

  11. Thermal lift generation and drag reduction in rarefied aerodynamics

    Science.gov (United States)

    Pekardan, Cem; Alexeenko, Alina

    2016-11-01

    With the advent of the new technologies in low pressure environments such as Hyperloop and helicopters designed for Martian applications, understanding the aerodynamic behavior of airfoils in rarefied environments are becoming more crucial. In this paper, verification of rarefied ES-BGK solver and ideas such as prediction of the thermally induced lift and drag reduction in rarefied aerodynamics are investigated. Validation of the rarefied ES-BGK solver with Runge-Kutta discontinous Galerkin method with experiments in transonic regime with a Reynolds number of 73 showed that ES-BGK solver is the most suitable solver in near slip transonic regime. For the quantification of lift generation, A NACA 0012 airfoil is studied with a high temperature surface on the bottom for the lift creation for different Knudsen numbers. It was seen that for lower velocities, continuum solver under predicts the lift generation when the Knudsen number is 0.00129 due to local velocity gradients reaching slip regime although lift coefficient is higher with the Boltzmann ES-BGK solutions. In the second part, the feasibility of using thermal transpiration for drag reduction is studied. Initial study in drag reduction includes an application of a thermal gradient at the upper surface of a NACA 0012 airfoil near trailing edge at a 12-degree angle of attack and 5 Pa pressure. It was seen that drag is reduced by 4 percent and vortex shedding frequency is reduced due to asymmetry introduced in the flow due to temperature gradient causing reverse flow due to thermal transpiration phenomena.

  12. Relative importance of expertise, lifting height and weight lifted on posture and lumbar external loading during a transfer task in manual material handling.

    Science.gov (United States)

    Plamondon, André; Larivière, Christian; Delisle, Alain; Denis, Denys; Gagnon, Denis

    2012-01-01

    The objective of this study was to measure the effect size of three important factors in manual material handling, namely expertise, lifting height and weight lifted. The effect of expertise was evaluated by contrasting 15 expert and 15 novice handlers, the effect of the weight lifted with a 15-kg box and a 23-kg box and the effect of lifting height with two different box heights: ground level and a 32 cm height. The task consisted of transferring a series of boxes from a conveyor to a hand trolley. Lifting height and weight lifted had more effect size than expertise on external back loading variables (moments) while expertise had low impact. On the other hand, expertise showed a significant effect of posture variables on the lumbar spine and knees. All three factors are important, but for a reduction of external back loading, the focus should be on the lifting height and weight lifted. The objective was to measure the effect size of three important factors in a transfer of boxes from a conveyor to a hand trolley. Lifting height and weight lifted had more effect size than expertise on external back loading variables but expertise was a major determinant in back posture.

  13. A lifting line model to investigate the influence of tip feathers on wing performance

    International Nuclear Information System (INIS)

    Fluck, M; Crawford, C

    2014-01-01

    Bird wings have been studied as prototypes for wing design since the beginning of aviation. Although wing tip slots, i.e. wings with distinct gaps between the tip feathers (primaries), are very common in many birds, only a few studies have been conducted on the benefits of tip feathers on the wing's performance, and the aerodynamics behind tip feathers remains to be understood. Consequently most aircraft do not yet copy this feature. To close this knowledge gap an extended lifting line model was created to calculate the lift distribution and drag of wings with tip feathers. With this model, is was easily possible to combine several lifting surfaces into various different birdwing-like configurations. By including viscous drag effects, good agreement with an experimental tip slotted reference case was achieved. Implemented in C++ this model resulted in computation times of less than one minute per wing configuration on a standard notebook computer. Thus it was possible to analyse the performance of over 100 different wing configurations with and without tip feathers. While generally an increase in wing efficiency was obtained by splitting a wing tip into distinct, feather-like winglets, the best performance was generally found when spreading more feathers over a larger dihedral angle out of the wing plane. However, as the results were very sensitive to the precise geometry of the feather fan (especially feather twist) a careless set-up could just as easily degrade performance. Hence a detailed optimization is recommended to realize the full benefits by simultaneously optimizing feather sweep, twist and dihedral angles. (paper)

  14. Evaluation of ceiling lifts: transfer time, patient comfort and staff perceptions.

    Science.gov (United States)

    Alamgir, Hasanat; Li, Olivia Wei; Yu, Shicheng; Gorman, Erin; Fast, Catherine; Kidd, Catherine

    2009-09-01

    Mechanical lifting devices have been developed to reduce healthcare worker injuries related to patient handling. The purpose of this study was to evaluate ceiling lifts in comparison to floor lifts based on transfer time, patient comfort and staff perceptions in three long-term care facilities with varying ceiling lift coverage. The time required to transfer or reposition patients along with patient comfort levels were recorded for 119 transfers. Transfers performed with ceiling lifts required on average less time (bed to chair transfers: 156.9 seconds for ceiling lift, 273.6 seconds for floor lift) and were found to be more comfortable for patients. In the three facilities, 143 healthcare workers were surveyed on their perceptions of patient handling tasks and equipment. For both transferring and repositioning tasks, staff preferred to use ceiling lifts and also found them to be less physically demanding. Further investigation is needed on repositioning tasks to ensure safe practice.

  15. DNA Profiles from Fingerprint Lifts-Enhancing the Evidential Value of Fingermarks Through Successful DNA Typing.

    Science.gov (United States)

    Subhani, Zuhaib; Daniel, Barbara; Frascione, Nunzianda

    2018-05-25

    This study evaluated the compatibility of the most common enhancement methods and lifting techniques with DNA profiling. Emphasis is placed on modern lifting techniques (i.e., gelatin lifters and Isomark™) and historical fingerprint lifts for which limited research has been previously conducted. A total of 180 fingerprints were deposited on a glass surface, enhanced, lifted, and processed for DNA typing. DNA could be extracted and profiled for all the powders and lifts tested and from both groomed fingerprints and natural prints with no significant difference in the percentage of profile recovered. DNA profiles could also be obtained from historical fingerprint lifts (79.2% of 72 lifts) with one or more alleles detected. These results demonstrate the compatibility between different powder/lift combinations and DNA profiling therefore augmenting the evidential value of fingerprints in forensic casework. © 2018 American Academy of Forensic Sciences.

  16. Autoignited laminar lifted flames of methane/hydrogen mixtures in heated coflow air

    KAUST Repository

    Choi, Byungchul; Chung, Suk-Ho

    2012-01-01

    Autoignited lifted flame behavior in laminar jets of methane/hydrogen mixture fuels has been investigated experimentally in heated coflow air. Three regimes of autoignited lifted flames were identified depending on initial temperature and hydrogen

  17. Cleft-lift operation for pilonidal sinuses under tumescent local anesthesia

    DEFF Research Database (Denmark)

    Bertelsen, Claus Anders

    2011-01-01

    The use of tumescent local anesthesia in the Bascom cleft-lift procedure has not been described before.......The use of tumescent local anesthesia in the Bascom cleft-lift procedure has not been described before....

  18. An unconventional mechanism of lift production during the downstroke in a hovering bird ( Zosterops japonicus)

    Science.gov (United States)

    Chang, Yu-Hung; Ting, Shang-Chieh; Liu, Chieh-Cheng; Yang, Jing-Tang; Soong, Chyi-Yeou

    2011-11-01

    An unconventional mechanism of ventral clap is exploited by hovering passerines to produce lift. Quantitative visualization of the wake flow, analysis of kinematics and evaluation of the transient lift force was conducted to dissect the biomechanical role of the ventral clap in the asymmetrical hovering flight of passerines. The ventral clap can first abate and then augment lift production during the downstroke; the net effect of the ventral clap on lift production is, however, positive because the extent of lift augmentation is greater than the extent of lift abatement. Moreover, the ventral clap is inferred to compensate for the zero lift production of the upstroke because the clapping wings induce a substantial elevation of the lift force at the end of the downstroke. Overall, our observations shed light on the aerodynamic function of the ventral clap and offer biomechanical insight into how a bird hovers without kinematically mimicking hovering hummingbirds.

  19. Lifting devices with minimum effort for testing, maintenance and repair at the example of a lifting rig for core internals

    Energy Technology Data Exchange (ETDEWEB)

    Pache, Martin [Westinghouse Electric Germany GmbH (Germany); Wiesendanger, Robert [Kernkraftwerk Beznau, NOK (Switzerland)

    2008-07-01

    Beznau is a Westinghouse built nuclear power plant in the Aargau area Switzerland. It consists of two PWR units, each providing 365 MWe net capacity. The units were set into operation in 1969 and 1972, respectively, and hold an unlimited license for operation, provided they continue to fulfill current legal and security requirements. Beznau's previous lifting rigs for core internals required a high effort in testing and maintenance. Moreover, a damage to one of the rigs nearly resulted in the inoperability of the rig. However, no element of the load chain was affected, so there was no danger of a crash, but it could have caused an extended outage. Hence, it was decided to replace the lifting rigs with a state-of-the-art functional design that reflects modern requirements on maintenance and testing. Although the plant was built to ASME standards and codes, the new lifting rigs have been designed to German KTA code for lifting devices (KTA 3902 / 3903 for equipment with increased requirements, as per section 4.3 of KTA 3902). Given KTA's demands on periodic testing, one main requirement on the new design was to minimize the testing effort for the new rigs. (orig.)

  20. 75 FR 33320 - Notice of Issuance of Final Determination Concerning a Lift Unit for an Overhead Patient Lift...

    Science.gov (United States)

    2010-06-11

    ... country of origin of the lift unit which may be offered to the U.S. Government under an undesignated government procurement package.'' Dated: June 7, 2010. Harold M. Singer, Director, Regulations and Disclosure Law Division, Office of International Trade. [FR Doc. 2010-14019 Filed 6-10-10; 8:45 am] BILLING CODE...

  1. 75 FR 31803 - Notice of Issuance of Final Determination Concerning a Lift Unit for an Overhead Patient Lift System

    Science.gov (United States)

    2010-06-04

    ... while avoiding injuries to caregivers. The merchandise at issue, the Likorall lift unit, is the... unit. The charger is made in the same non-TAA country as the hand control. ISSUE: What is the country... adapter, but rather because of what the completed handset and base provide: communication over telephone...

  2. A Real-Time Lift Detection Strategy for a Hip Exoskeleton.

    Science.gov (United States)

    Chen, Baojun; Grazi, Lorenzo; Lanotte, Francesco; Vitiello, Nicola; Crea, Simona

    2018-01-01

    Repetitive lifting of heavy loads increases the risk of back pain and even lumbar vertebral injuries to workers. Active exoskeletons can help workers lift loads by providing power assistance, and therefore reduce the moment and force applied on L5/S1 joint of human body when performing lifting tasks. However, most existing active exoskeletons for lifting assistance are unable to automatically detect user's lift movement, which limits the wide application of active exoskeletons in factories. In this paper, we propose a simple but effective lift detection strategy for exoskeleton control. This strategy uses only exoskeleton integrated sensors, without any extra sensors to capture human motion intentions. This makes the lift detection system more practical for applications in manufacturing environments. Seven healthy subjects participated in this research. Three different sessions were carried out, two for training and one for testing the algorithm. In the two training sessions, subjects were asked to wear a hip exoskeleton, controlled in transparent mode, and perform repetitive lifting and a locomotion circuit; lifting was executed with different techniques. The collected data were used to train the lift detection model. In the testing session, the exoskeleton was controlled in order to deliver torque to assist the lifting action, based on the lift detection made by the trained algorithm. The across-subject average accuracy of lift detection during online test was 97.97 ± 1.39% with subject-dependent model. Offline, the algorithm was trained with data acquired from all subjects to verify its performance for subject-independent detection, and an accuracy of 97.48 ± 1.53% was achieved. In addition, timeliness of the algorithm was quantitatively evaluated and the time delay was exoskeleton in assisting subjects in performing load lifting tasks. These results validate the promise of applying the proposed lift detection strategy for exoskeleton control aiming at lift

  3. Modelling of Turbulent Lifted Jet Flames using flamelets: a priori assessment and a posteriori validation

    OpenAIRE

    Ruan, S; Swaminathan, Nedunchezhian; Darbyshire, O

    2014-01-01

    This study focuses on the modelling of turbulent lifted jet flames using flamelets and presumed PDF approach with interests on both flame lift-off height and flame brush structure. First, flamelet models used to capture contributions from premixed and non-premixed modes to the partially premixed combustion in the lifted jet flame are assessed using a Direct Numerical Simulation (DNS) data for turbulent lifted hydrogen jet flame. The joint PDFs of mixture fraction, Z, and progress ...

  4. Numerical analysis of hydrodynamic forces acting on vertical lift gates; Analise dos esforcos hidrodinamicas em comportas hidraulicas

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Jell Lima de [Mecanica Pesada S.A., Taubate, SP (Brazil); Amorim, Jose Carlos Cesar [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil)]. E-mail: jcamorim@ime.eb.br

    1997-07-01

    A numerical analysis has been developed for calculating viscous flows controlled by a vertical lift gate and hydrodynamic forces acting on it. The numerical solution is obtained from the incompressible Navier-Stoles equations. The numerical techniques is based on a finite element method. A Poisson equation is derived from the pressure-weighted substitution of the full momentum equations into the continuity equation. Turbulence effects are simulated by a K-{epsilon} turbulence model. The procedure developed here is applied for a vertical lift gate operating in a CESP installation, and the results are compared with available experimental data at various opening positions. Good agreement is obtained for the velocity and pressure distributions. (author)

  5. THE SHAPING OF SOME LIFTING AND TRANSPORTATION SYSTEMS, USING AUTODESK INVENTOR

    Directory of Open Access Journals (Sweden)

    URSE Cătălin

    2011-11-01

    Full Text Available The paper presents, through the use of Autodesk Inventor software package, several mechanisms from the structure of lifting and transportation machines, in this case lifting system with winch operated by screw,lifting system type with muffle with hook, respectively bridge crane type.

  6. Conditions of using floating cranes for lifting sunken objects on inland waterways

    OpenAIRE

    Slobodan M. Radojević

    2012-01-01

    This paper presents the conditions for using floating cranes for lifting sunken vessels and other objects on inland waterways. Basic technical data are given together with technical details for the usage of floa ting cranes for lifting sunken objects. The paper points to the importance of lifting sunken objects and their removal from inland waterways in the Republic of Serbia.

  7. Conditions of using floating cranes for lifting sunken objects on inland waterways

    Directory of Open Access Journals (Sweden)

    Slobodan M. Radojević

    2012-04-01

    Full Text Available This paper presents the conditions for using floating cranes for lifting sunken vessels and other objects on inland waterways. Basic technical data are given together with technical details for the usage of floa ting cranes for lifting sunken objects. The paper points to the importance of lifting sunken objects and their removal from inland waterways in the Republic of Serbia.

  8. Testing two novel stump-lifting heads in a final felling Norway spruce stand

    Energy Technology Data Exchange (ETDEWEB)

    Kaerhae, K. (Metsaeteho Oy, Helsinki (Finland)), Email: kalle.karha@metsateho.fi; Mutikainen, A. (TTS Research, Rajamaeki (Finland)), Email: arto.mutikainen@tts.fi

    2009-07-01

    The use of stump and root wood chips has increased very rapidly in the 21st century in Finland: in the year 2000, the total consumption of stump wood chips for energy generation was 10 GWh, while in 2008 it was around 1.2 TWh. Metsaeteho Oy and TTS Research tested two new stump-lifting devices for lifting stumps in a final felling Norway spruce (picea abies) stand. In the time study with the Vaekevae Stump Processor lifting head, the productivity of stump lifting was 7,5 m3 / E{sub 0}-hour when lifting spruce stumps with a diameter of 30 cm from clayey soil, and 8.3 m3 /E{sub 0}-hour when lifting spruce stumps from sandy soil. When lifting stumps with a diameter of 40 cm, the stump-lifting productivity was 9.0 m3 /E{sub 0}-h (clay) and 10,5 m3 / E{sub 0}-h (sand). The results of this relatively restricted test indicated that the Vaekevae Stump Processor is s reliable and effective stump-lifting head that enables the harvesting of high-quality stump raw material for energy generation. The stump lifting productivity of the other lifting head (Jaervinen) was lower than that of the Vaekevae Strump Processor. Some development suggestions for the Jaervinen lifting head were presented and discussed. (orig.)

  9. An evaluation of methods assessing the physical demands of manual lifting in scaffolding

    NARCIS (Netherlands)

    Beek, van der A.J.; Mathiassen, S.E.; Windhorst, J.; Burdorf, A.

    2005-01-01

    Four methods assessing the physical demands of manual lifting were compared. The scaffolding job was evaluated and three distinct scaffolding tasks were ranked using: (1) the revised NIOSH lifting equation (NIOSH method), (2) lifting guidelines for the Dutch construction industry (Arbouw method),

  10. A comparison of two lifting assessment approaches in patients with chronic low back pain

    NARCIS (Netherlands)

    Soer, Remko; Poels, Bas J. J.; Geertzen, Jan H. B.; Reneman, Michiel F.

    2006-01-01

    The Progressive Isoinertial Lifting Evaluation (PILE) and the lifting test of the WorkWell Systems Functional Capacity Evaluation (WWS) are well known as lifting performance tests. The objective of this study was to study whether the PILE and the WWS can be used interchangeably in patients with

  11. 21 CFR 880.5510 - Non-AC-powered patient lift.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5510 Non-AC-powered patient lift. (a) Identification. A non-AC-powered patient lift is a hydraulic, battery, or mechanically powered device, either fixed or mobile, used to lift and transport a...

  12. Transport of timber by rope-and-pulley lift in steep seams

    Energy Technology Data Exchange (ETDEWEB)

    Spaniol, J

    1980-11-01

    This paper describes the rope-and-pulley lift used to transport timber and small items of equipment, which has been installed in tubbing in the return air drop-hole. Gives details of how the lift works and the equipment involved (winch, rope, slings, pulleys, safety and signalling arrangements). Looks at the future prospects of installing these lifts. (In French)

  13. Does team lifting increase the variability in peak lumbar compression in ironworkers?

    NARCIS (Netherlands)

    Faber, Gert; Visser, Steven; van der Molen, Henk F.; Kuijer, P. Paul F. M.; Hoozemans, Marco J. M.; van Dieën, Jaap H.; Frings-Dresen, Monique H. W.

    2012-01-01

    Ironworkers frequently perform heavy lifting tasks in teams of two or four workers. Team lifting could potentially lead to a higher variation in peak lumbar compression forces than lifts performed by one worker, resulting in higher maximal peak lumbar compression forces. This study compared

  14. Automation of workplace lifting hazard assessment for musculoskeletal injury prevention.

    Science.gov (United States)

    Spector, June T; Lieblich, Max; Bao, Stephen; McQuade, Kevin; Hughes, Margaret

    2014-01-01

    Existing methods for practically evaluating musculoskeletal exposures such as posture and repetition in workplace settings have limitations. We aimed to automate the estimation of parameters in the revised United States National Institute for Occupational Safety and Health (NIOSH) lifting equation, a standard manual observational tool used to evaluate back injury risk related to lifting in workplace settings, using depth camera (Microsoft Kinect) and skeleton algorithm technology. A large dataset (approximately 22,000 frames, derived from six subjects) of simultaneous lifting and other motions recorded in a laboratory setting using the Kinect (Microsoft Corporation, Redmond, Washington, United States) and a standard optical motion capture system (Qualysis, Qualysis Motion Capture Systems, Qualysis AB, Sweden) was assembled. Error-correction regression models were developed to improve the accuracy of NIOSH lifting equation parameters estimated from the Kinect skeleton. Kinect-Qualysis errors were modelled using gradient boosted regression trees with a Huber loss function. Models were trained on data from all but one subject and tested on the excluded subject. Finally, models were tested on three lifting trials performed by subjects not involved in the generation of the model-building dataset. Error-correction appears to produce estimates for NIOSH lifting equation parameters that are more accurate than those derived from the Microsoft Kinect algorithm alone. Our error-correction models substantially decreased the variance of parameter errors. In general, the Kinect underestimated parameters, and modelling reduced this bias, particularly for more biased estimates. Use of the raw Kinect skeleton model tended to result in falsely high safe recommended weight limits of loads, whereas error-corrected models gave more conservative, protective estimates. Our results suggest that it may be possible to produce reasonable estimates of posture and temporal elements of tasks

  15. Occupational lifting is associated with hip osteoarthritis: a Japanese case-control study.

    Science.gov (United States)

    Yoshimura, N; Sasaki, S; Iwasaki, K; Danjoh, S; Kinoshita, H; Yasuda, T; Tamaki, T; Hashimoto, T; Kellingray, S; Croft, P; Coggon, D; Cooper, C

    2000-02-01

    Hip osteoarthritis (OA) is a frequent cause of pain and disability in Western countries, but the disorder is less common in Japan. A case-control study in Britain found obesity, hip injury, and occupational lifting to be associated with hip OA among men and women. However, there are few epidemiological studies concerning factors associated with hip OA in Japan. We performed a comparable case-control study of the disorder in Japan, and contrasted the findings with those from Britain. The study was carried out in 2 health districts in Wakayama Prefecture, Japan. Cases were men and women aged > or = 45 years listed for total hip arthroplasty due to OA over one year, and who did not have an established cause of secondary OA (e.g., rheumatoid arthritis, ankylosing spondylitis). For each case, a control was selected randomly from the general population and was individually matched to the case for age, sex, and district of residence. Cases and controls were interviewed with a structured questionnaire about medical history, physical activity, socioeconomic factors, and occupation. Measurements were made of height and weight. One hundred fourteen cases (103 women, 11 men) were compared with 114 controls. We found no relationship between obesity and hip OA (OR = 1.0, 95% CI 0.5-1.9; highest vs lowest thirds of distribution of body mass index). There was, however, a statistically significant association between occupational lifting and hip OA, such that regular lifting of 25 kg in the individual's first job (OR = 3.6, 95% CI 1.3-9.7) or of 50 kg in their main job (OR = 4.0, 95% CI 1.1-14.2) was associated with increased risk of hip OA. These associations remained after adjustment for potential confounding variables. In contrast, those subjects who spent > 2 h each day sitting during their first job were significantly less likely to have the disorder (crude OR = 0.5, 95% CI 0.3-0.9). This association also remained statistically significant after adjustment for potential risk

  16. Aerodynamic Optimization for Distributed Electro Mechanical Actuators, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Traditional hydraulic actuation and control surface layout both limit span wise control of lift distribution, and require large volume within wing cross-section,...

  17. Statistics on Near Wall Structures and Shear Stress Distribution from 3D Holographic Measurement.

    Science.gov (United States)

    Sheng, J.; Malkiel, E.; Katz, J.

    2007-11-01

    Digital Holographic Microscopy performs 3D velocity measurement in the near-wall region of a turbulent boundary layer in a square channel over a smooth wall at Reτ=1,400. Resolution of ˜1μm over a sample volume of 1.5x2x1.5mm (x^+=50, y^+=60, z^+=50) is sufficient for resolving buffer layer and lower log layer structures, and for measuring instantaneous wall shear stress distributions from velocity gradients in the viscous sublayer. Results, based on 700 instantaneous realizations, provide detailed statistics on the spatial distribution of both wall stress components along with characteristic flow structures. Conditional sampling based on maxima and minima of wall shear stresses, as well as examination of instantaneous flow structures, lead to development of a conceptual model for a characteristic flow phenomenon that seems to generating extreme stress events. This structure develops as an initially spanwise vortex element rises away from the surface, due to local disturbance, causing a local stress minimum. Due to increasing velocity with elevation, this element bends downstream, forming a pair of inclined streamwise vortices, aligned at 45^0 to freestream, with ejection-like flow between them. Entrainment of high streamwise momentum on the outer sides of this vortex pair generates streamwise shear stress maxima, 70 δν downstream, which are displaced laterally by 35 δν from the local minimum.

  18. Design, Construction, and Validation of an Internally Lit Air-Lift Photobioreactor for Growing Algae

    Energy Technology Data Exchange (ETDEWEB)

    Hincapie, Esteban [Department of Mechanical Engineering, Russ College of Engineering and Technology, Ohio University, Athens, OH (United States); Stuart, Ben J., E-mail: stuart@ohio.edu [Department of Civil Engineering, Russ College of Engineering and Technology, Ohio University, Athens, OH (United States)

    2015-01-23

    A novel 28 L photobioreactor for growing algae was developed using fiber optics for internal illumination. The proposed design uses the air-lift principle to enhance the culture circulation and induce light/dark cycles to the microorganisms. Optical fibers were used to distribute photons inside the culture media providing an opportunity to control both light cycle and intensity. The fibers were coupled to an artificial light source; however, the development of this approach aims for the future use of natural light collected through parabolic solar collectors. This idea could also allow the use of opaque materials for photobioreactor construction significantly reducing costs and increasing durability. Internal light levels were determined in dry conditions and were maintained above 80 μmol/(s·m{sup 2}). The hydrodynamic equations of the air-lift phenomena were explored and used to define the geometric characteristics of the unit. The reactor was inoculated with the algae strain Chlorella sp. and sparged with air. The reactor was operated under batch mode and daily monitored for biomass concentration. The specific growth rate constant of the novel device was determined to be 0.011 h{sup −1}. The proposed design can be effectively and economically used in carbon dioxide mitigation technologies and in the production of algal biomass for biofuel and other bioproducts.

  19. Design, Construction, and Validation of an Internally Lit Air-Lift Photobioreactor for Growing Algae

    International Nuclear Information System (INIS)

    Hincapie, Esteban; Stuart, Ben J.

    2015-01-01

    A novel 28 L photobioreactor for growing algae was developed using fiber optics for internal illumination. The proposed design uses the air-lift principle to enhance the culture circulation and induce light/dark cycles to the microorganisms. Optical fibers were used to distribute photons inside the culture media providing an opportunity to control both light cycle and intensity. The fibers were coupled to an artificial light source; however, the development of this approach aims for the future use of natural light collected through parabolic solar collectors. This idea could also allow the use of opaque materials for photobioreactor construction significantly reducing costs and increasing durability. Internal light levels were determined in dry conditions and were maintained above 80 μmol/(s·m 2 ). The hydrodynamic equations of the air-lift phenomena were explored and used to define the geometric characteristics of the unit. The reactor was inoculated with the algae strain Chlorella sp. and sparged with air. The reactor was operated under batch mode and daily monitored for biomass concentration. The specific growth rate constant of the novel device was determined to be 0.011 h −1 . The proposed design can be effectively and economically used in carbon dioxide mitigation technologies and in the production of algal biomass for biofuel and other bioproducts.

  20. On the Use of Surface Porosity to Reduce Unsteady Lift

    Science.gov (United States)

    Tinetti, Ana F.; Kelly, Jeffrey J.; Bauer, Steven X. S.; Thomas, Russell H.

    2001-01-01

    An innovative application of existing technology is proposed for attenuating the effects of transient phenomena, such as rotor-stator and rotor-strut interactions, linked to noise and fatigue failure in turbomachinery environments. A computational study was designed to assess the potential of passive porosity technology as a mechanism for alleviating interaction effects by reducing the unsteady lift developed on a stator airfoil subject to wake impingement. The study involved a typical high bypass fan Stator airfoil (solid baseline and several porous configurations), immersed in a free field and exposed to the effects of a transversely moving wake. It was found that, for the airfoil under consideration, the magnitude of the unsteady lift could be reduced more than 18% without incurring significant performance losses.

  1. Computation of viscous transonic flow about a lifting airfoil

    Science.gov (United States)

    Walitt, L.; Liu, C. Y.

    1976-01-01

    The viscous transonic flow about a stationary body in free air was numerically investigated. The geometry chosen was a symmetric NACA 64A010 airfoil at a freestream Mach number of 0.8, a Reynolds number of 4 million based on chord, and angles of attack of 0 and 2 degrees. These conditions were such that, at 2 degrees incidence unsteady periodic motion was calculated along the aft portion of the airfoil and in its wake. Although no unsteady measurements were made for the NACA 64A010 airfoil at these flow conditions, interpolated steady measurements of lift, drag, and surface static pressures compared favorably with corresponding computed time-averaged lift, drag, and surface static pressures.

  2. Asymmetric Gepner models III. B-L lifting

    Energy Technology Data Exchange (ETDEWEB)

    Gato-Rivera, B. [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); Schellekens, A.N., E-mail: t58@nikhef.n [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); IMAPP, Radboud Universiteit, Nijmegen (Netherlands)

    2011-06-21

    In the same spirit as heterotic weight lifting, B-L lifting is a way of replacing the superfluous and ubiquitous U(1){sub B-L} with something else with the same modular properties, but different conformal weights and ground state dimensions. This method works in principle for all variants of (2,2) constructions, such as orbifolds, Calabi-Yau manifolds, free bosons and fermions and Gepner models, since it only modifies the universal SO(10)xE{sub 8} part of the CFT. However, it can only yield chiral spectra if the 'internal' sector of the theory provides a simple current of order 5. Here we apply this new method to Gepner models. Including exceptional invariants, 86 of them have the required order 5 simple current, and 69 of these yield chiral spectra. Three family spectra occur abundantly.

  3. Evolution of Water Lifting Devices (Pumps over the Centuries Worldwide

    Directory of Open Access Journals (Sweden)

    Stavros I. Yannopoulos

    2015-09-01

    Full Text Available The evolution of the major achievements in water lifting devices with emphasis on the major technologies over the centuries is presented and discussed. Valuable insights into ancient water lifting technologies with their apparent characteristics of durability, adaptability, and sustainability are provided. A comparison of the relevant technological developments in several early civilizations is carried out. These technologies are the underpinning of modern achievements in water engineering. They represent the best paradigm of probing the past and facing the future. A timeline of the historical development of water pumps worldwide through the last 5500 years of the history of mankind is presented. A chronological order is followed with emphasis on the major civilizations.

  4. DESIGN OF CITY BUS LIFT FOR THE HANDICAPPEDS

    Directory of Open Access Journals (Sweden)

    K. Turgut GÜRSEL

    2003-03-01

    Full Text Available Although the technological developments, the handicappeds do not take part sufficiently in the social and economic life, because buildings, road construction features and means of the transport are not suitable for them. In this study, a lift for handicappeds was designed, that is supposed to be installed to the middle door of city buses. The lift, whose installation should require a few changes at the bus, is driven by a hydraulic system from the street to the level of the bus floor and vice-versa. In the work, at first a construction was developed in accordance with the dimensions of the middle door of a city bus. After determining of dimensions of all elements, a hydraulic mechanism was constructed, that raises the handicapped, its wheelchair and the platform. Furthermore the construction of the elements of the system were determined, and its proofs of strength analysis were indicated

  5. Evaluation of structure integrity of the lifting handle of CRB

    Energy Technology Data Exchange (ETDEWEB)

    Wu, S.-Y. [Radiation Protection Association, Taiwan (China); Lin, S.-R. [Radiation Protection Association, Taiwan (China)], E-mail: srlin@iner.gov.tw; Kang, L.-C. [Institute of Nuclear Energy Research, Taiwan (China); Chang, Han-Jou [Department of Nuclear Safety, TPC, Taiwan (China)

    2008-09-15

    Since visual inspection was applied to inspect the control rod blades (CRBs) of nuclear power plants in Taiwan, indications have been found in areas such as roller-pin hole, sheath and tie-rod of CRB. Many preliminary safety analyses with conservative assumptions have been conducted to endorse the continuing operation of the units. The objective of this study is to evaluate the structural integrity of those CRBs during lifting operation. Detailed finite element models of the lifting handle of the CRB are built with emphasis on the postulated crack near the roller-pin hole. Both the D-215 type CRB and the Marathon type CRB are evaluated. It is concluded that the structural integrity is guaranteed even under the worst postulated situation.

  6. Lifting Term Rewriting Derivations in Constructor Systems by Using Generators

    Directory of Open Access Journals (Sweden)

    Adrián Riesco

    2015-01-01

    Full Text Available Narrowing is a procedure that was first studied in the context of equational E-unification and that has been used in a wide range of applications. The classic completeness result due to Hullot states that any term rewriting derivation starting from an instance of an expression can be "lifted" to a narrowing derivation, whenever the substitution employed is normalized. In this paper we adapt the generator- based extra-variables-elimination transformation used in functional-logic programming to overcome that limitation, so we are able to lift term rewriting derivations starting from arbitrary instances of expressions. The proposed technique is limited to left-linear constructor systems and to derivations reaching a ground expression. We also present a Maude-based implementation of the technique, using natural rewriting for the on-demand evaluation strategy.

  7. Minimally invasive facial rejuvenation endolaser mid-face lift.

    Science.gov (United States)

    Badin, A Z; Casagrande, C; Roberts, T; Saltz, R; Moraes, L M; Santiago, M; Chiaratti, M G

    2001-01-01

    Endolaser mid-face lift was performed on patients in a multi-center study over a 36-month period (Feb. 1998 to Feb. 2001). It permits significant facial rejuvenation through small incisions. This technique achieves aesthetic results and wider rejuvenation while being less traumatic and creating minimal morbidity. Combined with other procedures, it rejuvenates the face by three strategic methods: soft tissue suspension, reversal of photo aging, and correction of the depletion of volume. To achieve this triple result, the mid-face lift is performed by endoscopic approach, and in every case is combined with the endoscopic lift of the frontal area. Laser resurfacing was used to reverse skin photo damage. The Ultrapulse CO2 laser and/or the Ultrafine Erbium YAG(Coherent, Inc, Palo Alto, CA) were used. The third combined procedure was the introduction of fat graft to compensate the atrophy/ptosis of fat and the depletion of bone mass (other filling materials besides fat may be used, depending on the preference of the surgeon). Our method of fixation using the Casagrande Needle (an evolution of Reverdin Needle) makes the mechanical purchase on the tissues to be suspended much easier, permitting the intra-oral and/or infra-orbital incisions to be eliminated. The present study of the technical evolution of the endolaser mid-face lift method allows us to conclude that a very satisfactory outcome has been reached, offering patients a minimally invasive procedure, which can be performed under local anesthesia, with low morbidity, imperceptible incisions, and an excellent long-term result.

  8. Measurement and characterization of lift forces on drops and bubbles in microchannels

    Science.gov (United States)

    Stan, Claudiu; Guglielmini, Laura; Ellerbee, Audrey; Caviezel, Daniel; Whitesides, George; Stone, Howard

    2013-11-01

    The transverse motion of drops and bubbles within liquids flowing in pipes and channels is determined by the combination of several types of hydrodynamic lift forces with external forces. In microfluidic channels, lift forces have been used to position and sort particles with high efficiency and high accuracy. We measured lift forces on drops and bubbles and discriminated between different lift mechanisms under conditions characterized by low particle capillary numbers (0.0003 bubbles. We will present new experimental data that supports a dynamic interfacial mechanism for the second type of lift force, and discuss possible avenues for creating an analytical model for it.

  9. Endoscopic forehead lift in patients with male pattern baldness.

    Science.gov (United States)

    Shipchandler, Taha Z; Sultan, Babar; Byrne, Patrick J

    2012-01-01

    The presence of male pattern baldness poses a significant challenge when attempting to optimize treatment of the upper third of the face. The purpose of this study is to demonstrate and discuss results of the endoscopic forehead lift in patients with male pattern baldness. This was a retrospective case series done in an academic medical center. Eleven patients with male pattern baldness (Norwood class IV-VII) underwent endoscopic forehead lift for forehead creases and brow ptosis. All patients achieved smoothing of the forehead and elevation of the brow with no scalp anesthesia at 1 month postoperatively. All patients were pleased with the healing of their incisions in midline, paramedian, and temporal regions. Alloplastic fixation devices used were visible postoperatively in 2 patients initially. The endoscopic forehead lift is a suitable approach for treating the upper third of the face in the presence of male pattern baldness. The use of alloplastic fixation devices may be used in this patient population, but other fixation methods should be considered. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. A nonlinear dynamics of trunk kinematics during manual lifting tasks.

    Science.gov (United States)

    Khalaf, Tamer; Karwowski, Waldemar; Sapkota, Nabin

    2015-01-01

    Human responses at work may exhibit nonlinear properties where small changes in the initial task conditions can lead to large changes in system behavior. Therefore, it is important to study such nonlinearity to gain a better understanding of human performance under a variety of physical, perceptual, and cognitive tasks conditions. The main objective of this study was to investigate whether the human trunk kinematics data during a manual lifting task exhibits nonlinear behavior in terms of determinist chaos. Data related to kinematics of the trunk with respect to the pelvis were collected using Industrial Lumbar Motion Monitor (ILMM), and analyzed applying the nonlinear dynamical systems methodology. Nonlinear dynamics quantifiers of Lyapunov exponents and Kaplan-Yorke dimensions were calculated and analyzed under different task conditions. The study showed that human trunk kinematics during manual lifting exhibits chaotic behavior in terms of trunk sagittal angular displacement, velocity and acceleration. The findings support the importance of accounting for nonlinear dynamical properties of biomechanical responses to lifting tasks.

  11. Gurney flap—Lift enhancement, mechanisms and applications

    Science.gov (United States)

    Wang, J. J.; Li, Y. C.; Choi, K.-S.

    2008-01-01

    Since its invention by a race car driver Dan Gurney in 1960s, the Gurney flap has been used to enhance the aerodynamics performance of subsonic and supercritical airfoils, high-lift devices and delta wings. In order to take stock of recent research and development of Gurney flap, we have carried out a review of the characteristics and mechanisms of lift enhancement by the Gurney flap and its applications. Optimum design of the Gurney flap is also summarized in this paper. For the Gurney flap to be effective, it should be mounted at the trailing edge perpendicular to the chord line of airfoil or wing. The flap height must be of the order of local boundary layer thickness. For subsonic airfoils, an additional Gurney flap increases the pressure on the upstream surface of the Gurney flap, which increases the total pressure of the lower surface. At the same time, a long wake downstream of the flap containing a pair of counter-rotating vortices can delay or eliminate the flow separation near the trailing edge on the upper surface. Correspondingly, the total suction on the airfoil is increased. For supercritical airfoils, the lift enhancement of the Gurney flap mainly comes from its ability to shift the shock on the upper surface in the downstream. Applications of the Gurney flap to modern aircraft design are also discussed in this review.

  12. Three-dimensional motion analysis of the lumbar spine during "free squat" weight lift training.

    Science.gov (United States)

    Walsh, James C; Quinlan, John F; Stapleton, Robert; FitzPatrick, David P; McCormack, Damian

    2007-06-01

    Heavy weight lifting using a squat bar is a commonly used athletic training exercise. Previous in vivo motion studies have concentrated on lifting of everyday objects and not on the vastly increased loads that athletes subject themselves to when performing this exercise. Athletes significantly alter their lumbar spinal motion when performing squat lifting at heavy weights. Controlled laboratory study. Forty-eight athletes (28 men, 20 women) performed 6 lifts at 40% maximum, 4 lifts at 60% maximum, and 2 lifts at 80% maximum. The Zebris 3D motion analysis system was used to measure lumbar spine motion. Exercise was performed as a "free" squat and repeated with a weight lifting support belt. Data obtained were analyzed using SAS. A significant decrease (P free squat or when lifting using a support belt in any of the groups studied. Weight lifting using a squat bar causes athletes to significantly hyperextend their lumbar spines at heavier weights. The use of a weight lifting support belt does not significantly alter spinal motion during lifting.

  13. Foot positioning instruction, initial vertical load position and lifting technique: effects on low back loading.

    Science.gov (United States)

    Kingma, Idsart; Bosch, Tim; Bruins, Louis; van Dieën, Jaap H

    2004-10-22

    This study investigated the effects of initial load height and foot placement instruction in four lifting techniques: free, stoop (bending the back), squat (bending the knees) and a modified squat technique (bending the knees and rotating them outward). A 2D dynamic linked segment model was combined with an EMG assisted trunk muscle model to quantify kinematics and low back loading in 10 subjects performing 19 different lifting movements, using 10.5 kg boxes without handles. When lifting from a 0.05 m height with the feet behind the box, squat lifting resulted in 19.9% (SD 8.7%) higher net moments (p squat and stoop lifts, as well as the interaction with lifting height, could to a large extent be explained by changes in the horizontal L5/S1 intervertebral joint position relative to the load, the upper body acceleration, and lumbar flexion. Rotating the knees outward during squat lifts resulted in moments and compression forces that were smaller than in squat lifting but larger than in stoop lifting. Shear forces were small ( < 300 N) at the L4/L5 joint and substantial (1100 - 1400 N) but unaffected by lifting technique at the L5/S1 joint. The present results show that the effects of lifting technique on low back loading depend on the task context.

  14. Evaluation of ceiling lifts in health care settings: patient outcome and perceptions.

    Science.gov (United States)

    Alamgir, Hasanat; Li, Olivia Wei; Gorman, Erin; Fast, Catherine; Yu, Shicheng; Kidd, Catherine

    2009-09-01

    Ceiling lifts have been introduced into health care settings to reduce manual patient lifting and thus occupational injuries. Although growing evidence supports the effectiveness of ceiling lifts, a paucity of research links indicators, such as quality of patient care or patient perceptions, to the use of these transfer devices. This study explored the relationship between ceiling lift coverage rates and measures of patient care quality (e.g., incidence of facility-acquired pressure ulcers, falls, urinary infections, urinary incontinence, and assaults [patient to staff] in acute and long-term care facilities), as well as patient perceptions of satisfaction with care received while using ceiling lifts in a complex care facility. Qualitative semi-structured interviews were used to generate data. A significant inverse relationship was found between pressure ulcer rates and ceiling lift coverage; however, this effect was attenuated by year. No significant relationships existed between ceiling lift coverage and patient outcome indicators after adding the "year" variable to the model. Patients generally approved of the use of ceiling lifts and recognized many of the benefits. Ceiling lifts are not detrimental to the quality of care received by patients, and patients prefer being transferred by ceiling lifts. The relationship between ceiling lift coverage and pressure ulcer rates warrants further investigation. Copyright (c) 2009, SLACK Incorporated.

  15. Mathematical and empirical proof of principle for an on-body personal lift augmentation device (PLAD).

    Science.gov (United States)

    Abdoli-Eramaki, Mohammad; Stevenson, Joan M; Reid, Susan A; Bryant, Timothy J

    2007-01-01

    In our laboratory, we have developed a prototype of a personal lift augmentation device (PLAD) that can be worn by workers during manual handling tasks involving lifting or lowering or static holding in symmetric and asymmetric postures. Our concept was to develop a human-speed on-body assistive device that would reduce the required lumbar moment by 20-30% without negative consequences on other joints or lifting kinematics. This paper provides mathematical proof using simplified free body diagrams and two-dimensional moment balance equations. Empirical proof is also provided based on lifting trials with nine male subjects who executed sagittal plane lifts using three lifting styles (stoop, squat, free) and three different loads (5, 15, and 25kg) under two conditions (PLAD, No-PLAD). Nine Fastrak sensors and six in-line strap force sensors were used to estimate the reduction of compressive and shear forces on L4/L5 as well as estimate the forces transferred to the shoulders and knees. Depending on lifting technique, the PLAD applied an added 23-36Nm of torque to assist the back muscles during lifting tasks. The peak pelvic girdle contact forces were estimated and their magnitudes ranged from 221.3+/-11.2N for stoop lifting, 324.3+/-17.2N for freestyle lifts to 468.47+/-23.2N for squat lifting. The PLAD was able to reduce the compression and shear forces about 23-29% and 7.9-8.5%, respectively.

  16. Does team lifting increase the variability in peak lumbar compression in ironworkers?

    Science.gov (United States)

    Faber, Gert; Visser, Steven; van der Molen, Henk F; Kuijer, P Paul F M; Hoozemans, Marco J M; Van Dieën, Jaap H; Frings-Dresen, Monique H W

    2012-01-01

    Ironworkers frequently perform heavy lifting tasks in teams of two or four workers. Team lifting could potentially lead to a higher variation in peak lumbar compression forces than lifts performed by one worker, resulting in higher maximal peak lumbar compression forces. This study compared single-worker lifts (25-kg, iron bar) to two-worker lifts (50-kg, two iron bars) and to four-worker lifts (100-kg, iron lattice). Inverse dynamics was used to calculate peak lumbar compression forces. To assess the variability in peak lumbar loading, all three lifting tasks were performed six times. Results showed that the variability in peak lumbar loading was somewhat higher in the team lifts compared to the single-worker lifts. However, despite this increased variability, team lifts did not result in larger maximum peak lumbar compression forces. Therefore, it was concluded that, from a biomechanical point of view, team lifting does not result in an additional risk for low back complaints in ironworkers.

  17. [Origin of lifting and lowering theory and its herb pair study].

    Science.gov (United States)

    Guo, Zhao-Juan; Yuan, Yi-Ping; Kong, Li-Ting; Jia, Xiao-Yu; Wang, Ning-Ning; Dai, Ying; Zhai, Hua-Qiang

    2017-08-01

    Lifting and lowering theory is one of the important basis for guiding clinical medication. Through the study of ancient books and literature, we learned that lifting and lowering theory was originated in Huangdi Neijing, practiced more in the Shanghan Zabing Lun, established in Yixue Qiyuan, and developed in Compendium of Materia Medica and now. However, lifting and lowering theory is now mostly stagnated in the theoretical stage, with few experimental research. In the clinical study, the guiding role of lifting and lowering theory to prescriptions?mainly includes opposite?role?of lift and lower medicine property, mutual promotion of lift and lower medicine property, main role of lift medicine property and main role of lower medicine property. Under the guidance of lifting and lowering theory, the herb pair compatibility include herb combination of lift medicine property, herb combination of lift and lower medicine property and herb combination of lower medicine property. Modern biological technology was used in this study to carry out experimental research on the lifting and lowering theory, revealing the scientific connotation of it, which will help to promote clinical rational drug use. Copyright© by the Chinese Pharmaceutical Association.

  18. Diesel ignition delay and lift-off length through different methodologies using a multi-hole injector

    International Nuclear Information System (INIS)

    Payri, Raúl; Salvador, F.J.; Manin, Julien; Viera, Alberto

    2016-01-01

    Highlights: • Lift-off length and ignition delay are measured through different methodologies. • Oxygen concentration, temperature and injection pressure sweeps are performed. • A multi hole injector is compared with an equivalent single hole injector. • Multi hole injector has shorter ignition delay and lift-off length than single hole. • Empirical correlations were calculated for an analytical description of the results. - Abstract: In this paper, lift-off length has been measured via both broadband luminosity and OH chemiluminescence. In addition, ignition delay has also been measured via broadband chemiluminescence and Schlieren imaging. A 3 orifice injector from the Engine Combustion Network (ECN) set, referred to as Spray B, and a single component fuel (n-dodecane) was used. Experiments were carried out in a constant flow and pressure facility, that allowed to reproduce engine-like thermodynamic conditions, and enabled the study to be performed over a wide range of test conditions with a very high repetition rate. Data obtained was also compared with results from a single orifice injector also from the Engine Combustion Network, with analog orifice characteristics (90 μm outlet diameter and convergent shape) and technology as the injector used. Results showed that there is good correlation between the ignition delay measured through both methodologies, that oxygen concentration and injection pressure plays a minor role in the ignition delay, being ambient temperature and density the parameters with the highest influence. Lift-off length measurements showed significant differences between methodologies. Minor deviation was observed between injectors with different nozzle geometry (seat inclination angle), due to temperature variations along the chamber, highlighting the importance of temperature distribution along combustion vessels. Empirical correlations for lift-off and ignition delay were calculated, underlining the effect of the conditions on

  19. Feasibility study of modern airships, phase 1. Volume 2: Parametric analysis (task 3). [lift, weight (mass)

    Science.gov (United States)

    Lancaster, J. W.

    1975-01-01

    Various types of lighter-than-air vehicles from fully buoyant to semibuoyant hybrids were examined. Geometries were optimized for gross lifting capabilities for ellipsoidal airships, modified delta planform lifting bodies, and a short-haul, heavy-lift vehicle concept. It is indicated that: (1) neutrally buoyant airships employing a conservative update of materials and propulsion technology provide significant improvements in productivity; (2) propulsive lift for VTOL and aerodynamic lift for cruise significantly improve the productivity of low to medium gross weight ellipsoidal airships; and (3) the short-haul, heavy-lift vehicle, consisting of a simple combination of an ellipsoidal airship hull and existing helicopter componentry, provides significant potential for low-cost, near-term applications for ultra-heavy lift missions.

  20. Airfoil design: Finding the balance between design lift and structural stiffness

    DEFF Research Database (Denmark)

    Bak, Christian; Gaudern, Nicholas; Zahle, Frederik

    2014-01-01

    When upscaling wind turbine blades there is an increasing need for high levels of structural efficiency. In this paper the relationships between the aerodynamic characteristics; design lift and lift-drag ratio; and the structural characteristics were investigated. Using a unified optimization setup......, the design lift coefficient increases if the box length reduces and at the same time the relative thickness increases. Even though the conclusions are specific to the airfoil design approach used, the study indicated that an increased design lift required slightly higher relative thickness compared...... to airfoils with lower design lift to maintain the flapwise stiffness. Also, the study indicated that the lift-drag ratio as a function of flapwise stiffness was relatively independent of the airfoil design with a tendency that the lift-drag ratio decreased for large box lengths. The above conclusions were...

  1. Lifting bloody footwear impressions using alginate casts followed by chemical enhancement.

    Science.gov (United States)

    Wiesner, Sarena; Izraeli, Elad; Shor, Yaron; Domb, Avi

    2013-05-01

    A method for lifting bloody footwear impressions using alginate casts and enhancing the lifted impressions with amido black is presented. On rough or dark substrates, background interferences may conceal significant details of footwear impressions. Illumination with alternative light sources and chemically enhancing the bloody footwear impressions may reveal additional details, but sometimes, lifting footwear impressions prior to enhancing is the only way to expose hidden details (by using blood reagents not adequate on the original). Several cast formulations were tested for lifting the footwear impressions. The best results were achieved using Aroma fine®. Enhancement of the footwear impressions was attempted with several reagents prior to lifting, during the casting process, and on the lifted footwear impressions. Applying amido black to footwear impressions lifted with alginate produced the sharpest and most detailed footwear impressions. Alginate castings followed by chemical enhancement with amido black may produce high-quality footwear impressions for comparison. © 2013 American Academy of Forensic Sciences.

  2. High-Temperature-High-Volume Lifting for Enhanced Geothermal Systems

    Energy Technology Data Exchange (ETDEWEB)

    Turnquist, Norman [GE Global Research, Munchen (Germany); Qi, Xuele [GE Global Research, Munchen (Germany); Raminosoa, Tsarafidy [GE Global Research, Munchen (Germany); Salas, Ken [GE Global Research, Munchen (Germany); Samudrala, Omprakash [GE Global Research, Munchen (Germany); Shah, Manoj [GE Global Research, Munchen (Germany); Van Dam, Jeremy [GE Global Research, Munchen (Germany); Yin, Weijun [GE Global Research, Munchen (Germany); Zia, Jalal [GE Global Research, Munchen (Germany)

    2013-12-20

    This report summarizes the progress made during the April 01, 2010 – December 30, 2013 period under Cooperative Agreement DE-EE0002752 for the U.S. Department of Energy entitled “High-Temperature-High-Volume Lifting for Enhanced Geothermal Systems.” The overall objective of this program is to advance the technology for well fluids lifting systems to meet the foreseeable pressure, temperature, and longevity needs of the Enhanced Geothermal Systems (EGS) industry for the coming ten years. In this program, lifting system requirements for EGS wells were established via consultation with industry experts and site visits. A number of artificial lift technologies were evaluated with regard to their applicability to EGS applications; it was determined that a system based on electric submersible pump (ESP) technology was best suited to EGS. Technical barriers were identified and a component-level technology development program was undertaken to address each barrier, with the most challenging being the development of a power-dense, small diameter motor that can operate reliably in a 300°C environment for up to three years. Some of the targeted individual component technologies include permanent magnet motor construction, high-temperature insulation, dielectrics, bearings, seals, thrust washers, and pump impellers/diffusers. Advances were also made in thermal management of electric motors. In addition to the overall system design for a full-scale EGS application, a subscale prototype was designed and fabricated. Like the full-scale design, the subscale prototype features a novel “flow-through-the-bore” permanent magnet electric motor that combines the use of high temperature materials with an internal cooling scheme that limits peak internal temperatures to <330°C. While the full-scale high-volume multi-stage pump is designed to lift up to 80 kg/s of process water, the subscale prototype is based on a production design that can pump 20 kg/s and has been modified

  3. Lift-up construction method of apron pavement in the airport. Kuko epuron hoso no lift up koho

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, H. (Ministry of Transport, Tokyo (Japan))

    1994-03-25

    Frequently used airports do not allow the period during which facilities are shutdown for cultivation in the repair work of sunk concrete pavement. The present report describes the outline of the lift-up construction method by means of prestressed concrete pavement which allows repair work only in the night. The method has been developed and demonstrated this time in the construction of off-shore development of Tokyo International Airport. The fundamental procedures are as follows: A [phi] 16cm hole is drilled with a core boring machine into the pavement slab in the sunk area; the roadbed is excavated around the hole in the volume of ca. 45cm in diameter and ca. 30cm in thickness; a reaction bed of concrete and a metal fixture of the hydraulic jack are installed; the reaction bed is exerted with a force by the jack to lift up the pavement slab; and finally the gap made between the pavement slab and the road bed is grouted with cement milk. In a demonstration test construction, lift-up of 3.5cm over ca. 3500m[sup 2] was performed during a total of four days of one day in the daytime and three days in the night. 7 figs.

  4. Design Considerations for the Electrical Power Supply of Future Civil Aircraft with Active High-Lift Systems

    Directory of Open Access Journals (Sweden)

    J.-K. Mueller

    2018-01-01

    Full Text Available Active high-lift systems of future civil aircraft allow noise reduction and the use of shorter runways. Powering high-lift systems electrically have a strong impact on the design requirements for the electrical power supply of the aircraft. The active high-lift system of the reference aircraft design considered in this paper consists of a flexible leading-edge device together with a combination of boundary-layer suction and Coanda-jet blowing. Electrically driven compressors distributed along the aircraft wings provide the required mass flow of pressurized air. Their additional loads significantly increase the electric power demand during take-off and landing, which is commonly provided by electric generators attached to the aircraft engines. The focus of the present study is a feasibility assessment of alternative electric power supply concepts to unburden or eliminate the generator coupled to the aircraft engine. For this purpose, two different concepts using either fuel cells or batteries are outlined and evaluated in terms of weight, efficiency, and technology availability. The most promising, but least developed alternative to the engine-powered electric generator is the usage of fuel cells. The advantages are high power density and short refueling time, compared to the battery storage concept.

  5. The Effect of Midline Corset Platysmaplasty on Degree of Face-lift Flap Elevation During Concomitant Deep-Plane Face-lift: A Cadaveric Study.

    Science.gov (United States)

    Jacono, Andrew A; Malone, Melanie H

    2016-05-01

    The evaluation of the effects of midline platysmaplasty concomitant with rhytidectomy. To determine whether midline platysmaplasty limits the degree of lift during deep-plane face-lift. Deep-plane rhytidectomy was performed on 10 cadaveric hemifaces. The redundant skin for excision after performing the face-lift was measured with and without midline platymaplasty. Deep-plane rhytidectomy. The redundant skin was measured preauricularly in the vertical and horizontal dimension, and postauricularly after deep-plane face-lift and after adding a midline platysmaplasty. Concomitant midline platysmaplasty significantly reduced the amount of lift during concomitant deep-plane rhytidectomy preauricularly in the vertical dimension by 40.5% (from 37.0 mm excess skin redraped to 22.0 mm) and postauricularly by 23.9% (from 40.6 mm excess skin redraped to 30.9 mm) (P jawline and midface during rhytidectomy. NA.

  6. The design of lifting attachments for the erection of large diameter and heavy wall pressure vessels

    International Nuclear Information System (INIS)

    Antalffy, Leslie P.; Miller, George A.; Kirkpatrick, Kenneth D.; Rajguru, Anil; Zhu, Yong

    2016-01-01

    Lifting attachments for the erection of large diameter and heavy wall pressure vessels require special consideration to ensure that their attachment to their vessel shells or heads do not overstress the vessel during the erection process when lifting these from grade onto their respective foundations. Today, in refinery and petrochemical services, large diameter vessels with diameters ranging up to 15 m and reactors with lifting weights in the range of 700–1400 tons are not uncommon. In today's fabrication market, these vessels may be purchased and fabricated in shops dispersed globally and will require unique equipment for their safe handling, transportation and subsequent erection. The challenge is to design the lifting attachments in such a manner that the attachments provide a safe, cost effective and effective solution based upon the limitations of the job site lift equipment available for erection. Such equipment for the transportation and subsequent lifting of large diameter and heavy wall pressure equipment is usually scarce and quite expensive. Planning ahead, well in advance of the lift date is almost a mandatory requirement. Usually, the specific parameters of the vessel to be lifted and the lifting equipment available at the site will dictate the type of lifting attachments to be designed for the vessel. Once the type of vessel attachment has been chosen, careful consideration must be given to the design of attachments to the pressure vessel in consideration to ensure that the vessel and lifting components are not overstressed during the lifting process. The paper also discusses different types of lifting attachments that may be attached to each end of the vessel either by bolting or welding and discusses the pros and cons of each. The paper also provides an example of a finite element analysis (FEA) of a top nozzle, a FEA of a pair of lifting trunnions and a FEA of welded on lifting lugs for buried pipe. The purpose of the paper is to outline the

  7. A status report on artificial lift systems and challenges in North Dakota horizontal completions

    Energy Technology Data Exchange (ETDEWEB)

    Fangmeier, K. [Amerada Hess Corp., ND (United States)

    2005-07-01

    Partially pressure depleted reservoirs and unfavorable horizontal flow geometries can impact artificial lift designs and diagnostics. In addition, terrain slugging, drilling fines, high gas volume fractions, H{sub 2}S gas and high bottom hole temperatures also pose challenges. This paper provides an overview of various systems utilized by Amerada Hess, a company which examines methods of reducing gas lift gas volumes to achieve maximum flow. A description of naturally fractured reservoirs and limited natural fractures was provided. A comparison was presented between the original conditions at Beaver Lodge Madison and existing conditions with horizontal development. Various artificial lift challenges were examined. It was suggested that high volume lift utilizing gas lift was the preferred artificial lift system for high volume wells. It was noted that downhole sensors can be used as an indicator of potential run life. However, reliability is limited by downhole operating temperatures and electrical ground faults. A comparison of friendly and unfriendly flow systems was presented, as well as a gas lift pressure chart. A summary of average gas volume systems was provided as well as an example of a response to increase drawdown. Examples of downhole Electric Submersible Pump (ESP) sensors were provided, as well as possible flowing pressure profiles in horizontal completion because of the constraints of lift capacity. It was concluded that a single point injection and proven gas lift system is the next step in high volume lift strategy. 2 tabs, 16 figs.

  8. Heavy-Lift for a New Paradigm in Space Operations

    Science.gov (United States)

    Morris, Bruce; Burkey, Martin

    2010-01-01

    NASA is developing an unprecedented heavy-lift capability to enable human exploration beyond low Earth orbit (LEO). This capability could also significantly enhance numerous other missions of scientific, national security, and commercial importance. That capability is currently configured as the Ares V cargo launch vehicle. This capability will eclipse the capability the United States lost with the retirement of the Saturn V. It is capable of launching roughly 53 percent more payload mass to trans lunar injection (TLI) and 30 percent more payload mass to LEO than its Apollo Program predecessor. Ares V is a major element of NASA's Constellation Program, which also includes the Ares I crew launch vehicle (CLV), Orion crew exploration vehicle (CEV), and a lunar lander for crew and cargo. As currently configured, Ares V will be capable of launching 413,800 pounds (187.7 mT) to LEO, 138,500 pounds (63 mT) direct to the Moon or 156,700 pounds (71.1 mT) in its dual-launch architecture role with Ares I. Its 33-foot (10 m) shroud provides unprecedented payload volume. Assessment of astronomy and planetary science payload requirements since spring 2008 has indicated that a Saturn V-class heavy-lift vehicle has the potential to support a range of payloads and missions. This vehicle configuration enables some missions previously considered difficult or impossible and enhances many others. Collaborative design/architecture inputs, exchanges, and analyses have already begun between scientists and payload developers. This early dialogue between NASA engineers and payload designers allows both communities to shape their designs and operational concepts to be mutually supportive to the extent possible with the least financial impact. This paper provides an overview of the capabilities of a heavy-lift vehicle to launch payloads with increased mass and/or volume and reduce technical and cost risk in both design and operations.

  9. Topological wave functions and the 4D-5D lift

    OpenAIRE

    Gao, Peng; Pioline, Boris

    2008-01-01

    We revisit the holomorphic anomaly equations satisfied by the topological string amplitude from the perspective of the 4D-5D lift, in the context of ''magic'' N=2 supergravity theories. In particular, we interpret the Gopakumar-Vafa relation between 5D black hole degeneracies and the topological string amplitude as the result of a canonical transformation from 4D to 5D charges. Moreover we use the known Bekenstein-Hawking entropy of 5D black holes to constrain the asymptotic behavior of the t...

  10. Fuel-conservative guidance system for powered-lift aircraft

    Science.gov (United States)

    Erzberger, H.; Mclean, J. D.

    1979-01-01

    A concept for automatic terminal area guidance, comprising two modes of operation, was developed and evaluated in flight tests. In the predictive mode, fuel efficient approach trajectories are synthesized in fast time. In the tracking mode, the synthesized trajectories are reconstructed and tracked automatically. An energy rate performance model derived from the lift, drag, and propulsion system characteristics of the aircraft is used in the synthesis algorithm. The method optimizes the trajectory for the initial aircraft position and wind and temperature profiles encountered during each landing approach. The design theory and the results of simulations and flight tests using the Augmentor Wing Jet STOL Research Aircraft are described.

  11. Simplified theory of an active lift turbine with controlled displacement

    OpenAIRE

    Lecanu , Pierre ,; Breard , Joel; Mouazé , Dominique

    2016-01-01

    It is presented in this article, a simplified theory of the active lift turbine which has been the subject of several patent[4, 5, 11]. A simplified theory is proposed to extend the Betz limit of the yield on vertical axis wind turbine. This work can be extended either on wind driven or marine current turbine. Based on kinetic energy calculation , that theory demonstrates that the radial force acting on the blade can be used to extend the maximum recoverable power, mainly by transforming a li...

  12. [Rhabdomyolysis after lifting IKEA bags in a man using sertraline].

    Science.gov (United States)

    Kummen, Ingvild; Jensen, Thomas Giver

    2016-12-12

    We present a case of a 28-year-old male, using sertraline, who experienced progressive oedema in both upper extremities after having lifted two IKEA bags weighing 20 kg each from his car up to the third floor. Blood creatine kinase (CK) level was measured 5,260 U/l, and the patient was admitted for oral rehydration with the diagnosis rhabdomyolysis. The MRI showed swelling in the triceps muscles and latissimus dorsi muscles resulting in compression of the brachial vein. We discuss the pathomechanism behind the increased CK level and the swelling, and the possible effect sertraline may have had on the development of rhabdomyolysis.

  13. Heavy Lift for National Security: The Ares V

    Science.gov (United States)

    Sumrall, Phil

    2009-01-01

    The NASA Ares Projects Office is developing the launch vehicles to move the United States and humanity beyond low earth orbit. Ares I is a crewed vehicle, and Ares V is a heavy lift vehicle being designed to launch cargo into LEO and transfer cargo and crews to the Moon. This is a snapshot of development and capabilities. Ares V is early in the requirements formulation stage of development pending the outcome of the Review of U.S. Human Space Flight Plans Committee and White House action. The Ares V vehicle will be considered a national asset, creating unmatched opportunities for human exploration, science, national security, and space business.

  14. Heavy Lift Vehicle (HLV) Avionics Flight Computing Architecture Study

    Science.gov (United States)

    Hodson, Robert F.; Chen, Yuan; Morgan, Dwayne R.; Butler, A. Marc; Sdhuh, Joseph M.; Petelle, Jennifer K.; Gwaltney, David A.; Coe, Lisa D.; Koelbl, Terry G.; Nguyen, Hai D.

    2011-01-01

    A NASA multi-Center study team was assembled from LaRC, MSFC, KSC, JSC and WFF to examine potential flight computing architectures for a Heavy Lift Vehicle (HLV) to better understand avionics drivers. The study examined Design Reference Missions (DRMs) and vehicle requirements that could impact the vehicles avionics. The study considered multiple self-checking and voting architectural variants and examined reliability, fault-tolerance, mass, power, and redundancy management impacts. Furthermore, a goal of the study was to develop the skills and tools needed to rapidly assess additional architectures should requirements or assumptions change.

  15. Inducing Lift on Spherical Particles by Traveling Magnetic Fields

    Science.gov (United States)

    Mazuruk, Konstantin; Grugel, Richard N.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    Gravity induced sedimentation of suspensions is a serious drawback to many materials and biotechnology processes, a factor that can, in principle, be overcome by utilizing an opposing Lorentz body force. In this work we demonstrate the utility of employing a traveling magnetic field (TMF) to induce a lifting force on particles dispersed in the fluid. Theoretically, a model has been developed to ascertain the net force, induced by TMF, acting on a spherical body as a function of the fluid medium's electrical conductivity and other parameters. Experimentally, the model is compared to optical observations of particle motion in the presence of TMF.

  16. Occupational lifting during pregnancy and child's birth size in a large cohort study

    DEFF Research Database (Denmark)

    Juhl, Mette; Larsen, Pernille Stemann; Andersen, Per Kragh

    2014-01-01

    OBJECTIVES: It has been suggested that the handling of heavy loads during pregnancy is associated with impaired fetal growth. We examined the association between quantity and frequency of maternal occupational lifting and the child's size at birth, measured by weight, length, ponderal index, small......-for-gestational-age (SGA), abdominal circumference, head circumference, and placental weight. METHODS: We analyzed birth size from the Danish Medical Birth Registry of 66 693 live-born children in the Danish National Birth Cohort according to the mother's self-reported information on occupational lifting from telephone...... women with occupational lifting versus women with no lifting, but the differences were very small, and there was a statistically significant trend only for placental weight showing lighter weight with increasing number of kilos lifted per day. In jobs likely to include person-lifting, we found increased...

  17. Modeling and Design of Hybrid PEM Fuel Cell Systems for Lift Trucks

    DEFF Research Database (Denmark)

    Hosseinzadeh, Elham

    driven lift trucks are being used more and more in different companies to reduce their emissions. However, battery driven lift trucks need a long time to recharge and thus may be out of work for a long time. Fuel cell driven lift trucks diminish this problem and are therefore getting more attention...... in a fork-lift truck. In order for the ejector to operate in the largest possible range of load, different approaches (with fixed nozzle and variable nozzle ejectors) have been investigated. Different geometries have been studied in order to optimize the ejector. The optimization is carried out not only...... a virtual fork-lift system. This investigation examines important performance metrics, such as hydrogen consumption and battery SOC as a function of the fuel cell and battery size, control strategy, drive cycle, and load variation for a fork-lift truck system. This study can be used as a benchmark...

  18. Occupational heavy lifting and risk of ischemic heart disease and all-cause mortality

    DEFF Research Database (Denmark)

    Petersen, Christina Bjørk; Eriksen, Louise; Tolstrup, Janne S

    2012-01-01

    ABSTRACT: BACKGROUND: Occupational heavy lifting is known to impose a high cardiovascular strain, but the risk of ischemic heart disease (IHD) from occupational heavy lifting is unknown. The objective was to investigate the association between occupational heavy lifting and risk of IHD and all...... cardiovascular disease at baseline. Conventional risk factors for the outcomes IHD and all-cause mortality were controlled for in Cox analyses. RESULTS: Among men, heavy lifting was associated with increased risk for IHD (hazard ratio (HR): 1.52, 95 % Confidence interval (95 % CI): 1.15, 2.02), while a decreased...... risk was associated with occupational (HR: 0.50, 95 % CI: 0.37, 0.68) and leisure time (HR: 0.73, 95 % CI: 0.56, 0.95) physical activity. Referencing men with high occupational physical activity and no heavy lifting, men with high occupational physical activity and heavy lifting did not have...

  19. Apparatus Producing an Even Distribution of Strain into Carries

    Science.gov (United States)

    Hrabovský, Leopold

    2017-10-01

    In many high-rise residential buildings or multi-storey warehouses, machinery, so called lifts, is used for the vertical transportation of people or weights between two or more altitudinally distant places. Carriers used for lifts are steel ropes or sprocket chains, on which a cage or a counterbalance is hinged. Apparatus of all carriers, attached to the hinge of the cage or counterbalance, should be even. This can be made only by hammer hinge. Fixed or springe hinge cannot be a perfect equalizing apparatus. This article describes an apparatus, which allows an even distribution of the strain into lift carriers, which use springe hinge of carrier ropes.

  20. Foot positioning instruction, initial vertical load position and lifting technique: effects on low back loading

    OpenAIRE

    Kingma, I.; Bosch, T.; Bruins, L.; van Dieen, J.H.

    2004-01-01

    This study investigated the effects of initial load height and foot placement instruction in four lifting techniques: free, stoop (bending the back), squat (bending the knees) and a modified squat technique (bending the knees and rotating them outward). A 2D dynamic linked segment model was combined with an EMG assisted trunk muscle model to quantify kinematics and low back loading in 10 subjects performing 19 different lifting movements, using 10.5 kg boxes without handles. When lifting from...

  1. Reasons for the appearance of pulsations in gas-lift wells and methods of eliminating them

    Energy Technology Data Exchange (ETDEWEB)

    Sibirev, A P; Grekhov, V V; Leonov, V A; Shigapov, R R

    1985-01-01

    It is shown that the main reason for pulsation in the gas-lift well output is lack of coordinated operation between the bed and the gas-lift lifter. A plan is suggested for making decisions to conduct work to detect and eliminate pulsations in the gas-lift well output which permit elimination of the pulsation in the shortest time and with the least outlays.

  2. Numerical Simulation and Experiment of a Lifting Body with Leading-Edge Rotating Cylinder

    OpenAIRE

    A. Badarudin; C. S. Oon; S. N. Kazi; N. Nik-Ghazali; Y. J. Lee; W. T. Chong

    2013-01-01

    An experimental and simulation flight test has been carried out to evaluate the longitudinal gliding characteristics of a lifting body with blunted half-cone geometry. The novelty here is the lifting body's pitch control mechanism, which consists of a pair of leading-edge rotating cylinders. Flight simulation uses aerodynamic data from computational fluid dynamics supported by wind-tunnel test. Flight test consists of releasing an aluminum lifting body model from a moving vehicle at the appro...

  3. Characterization of Liquid Fuel Evaporation of a Lifted Methanol Spray Flame in a Vitiated Coflow Burner

    Science.gov (United States)

    Cabra, Ricardo; Dibble, Robert W.; Chen, Jyh-Yuan

    2002-01-01

    An experimental investigation of lifted spray flames in a coflow of hot, vitiated gases is presented. The vitiated coflow burner is a spray flame that issues into a coaxial flow of hot combustion products from a lean, premixed H2/Air flame. The spray flame in a vitiated coflow emulates the combustion that occurs in many advanced combustors without the detailed fluid mechanics. Two commercially available laser diagnostic systems are used to characterize the spray flame and to demonstrate the vitiated coflow burner's amenability to optical investigation. The Ensemble Particle Concentration and Size (EPCS) system is used to measure the path-average droplet size distribution and liquid volume fraction at several axial locations while an extractive probe instrument named the Real-time Fuel-air Analyzer (RFA) is used to measure the air to fuel ratio downstream of the spray nozzle with high temporal and spatial resolution. The effect of coflow conditions (stoichiometry) and dilution of the fuel with water was studied with the EPCS optical system. As expected, results show that water retards the evaporation and combustion of fuels. Measurements obtained by the RFA extractive probe show that while the Delavan manufactured nozzle does distribute the fuel over the manufacturer specified spray angle, it unfortunately does not distribute the fuel uniformly, providing conditions that may result in the production of unwanted NOx. Despite some limitations due to the inherent nature of the experimental techniques, the two diagnostics can be readily applied to spray flames in the vitiated coflow environment.

  4. Effect of hydrogen addition on autoignited methane lifted flames

    KAUST Repository

    Choin, Byung Chul

    2012-01-01

    Autoignited lifted flames in laminar jets with hydrogen-enriched methane fuels have been investigated experimentally in heated coflow air. The results showed that the autoignited lifted flame of the methane/hydrogen mixture, which had an initial temperature over 920 K, the threshold temperature for autoignition in methane jets, exhibited features typical of either a tribrachial edge or mild combustion depending on fuel mole fraction and the liftoff height increased with jet velocity. The liftoff height in the hydrogen-assisted autoignition regime was dependent on the square of the adiabatic ignition delay time for the addition of small amounts of hydrogen, as was the case for pure methane jets. When the initial temperature was below 920 K, where the methane fuel did not show autoignition behavior, the flame was autoignited by the addition of hydrogen, which is an ignition improver. The liftoff height demonstrated a unique feature in that it decreased nonlinearly as the jet velocity increased. The differential diffusion of hydrogen is expected to play a crucial role in the decrease in the liftoff height with increasing jet velocity.

  5. How neotropical hummingbird versus bat species generate lift to hover

    Science.gov (United States)

    Ingersoll, Rivers; Lentink, David

    2017-11-01

    Both hummingbirds and nectar bats evolved the ability to hover in front of flowers providing them access to energy rich nectar. Hummingbirds have been found to generate more than a quarter of their weight support during the upstroke by inverting their wings-much more than generalist birds during slow hovering flight. In contrast to hummingbirds, bats have membrane wings which they partially fold during the upstroke. It has been hypothesized that bats generate some vertical lift force during the upstroke although the complex wake structures make it hard to quantify upstroke function through flow measurement. To compare the kinematics and aerodynamic forces generated by both groups, we caught and trained over 100 individuals spanning 18 hummingbird and 3 bat species in Coto Brus, Costa Rica. We used 3D calibrated high-speed cameras to measure wingbeat kinematics and a novel aerodynamic force platform to measure the instantaneous vertical lift force in vivo. This data gives us new insight into how ecology shapes the evolution of hovering flight across taxa in the same ecosystem. This research is supported by NSF CAREER Award 1552419 and the KACST Center of Excellence for Aeronautics and Astronautics at Stanford.

  6. FLEXOWELL vertical lift systems in underground mining and construction industries

    Energy Technology Data Exchange (ETDEWEB)

    Paelke, J.W.

    1988-06-01

    Mining and quarrying companies are seeking improved and more continuous transport methods to reduce their costs. Frequently in the past the use of conveyors has been ruled out in steep mining applications but now the Scholtz FLEXOWELL belting which can be used at angles up to the vertical will enable many mines to consider complete belt conveyor systems for the first time. Applications will include steep conveyors for surface mines and quarries in order to eliminate the need for expensive and noisy fleets of trucks and the associated requirements to maintain haul roads. A further field is in the use of steep or vertical conveyors in underground mines to ensure improved continuity of output in existing shaft systems or reduced development costs in new mines. The Scholtz company, a member of the Nokia Group which had sales of about 3.5 billion U.S. Dollars in 1987, has more than 20 years experience with their FLEXOWELL belts. Over 40,000 units are operating around the world. These are already fully proven for vertical lifts of over 100 m (328ft) and up to 500 m (1,640 ft) is possible. Tonnage ratings of up to 4,000 t/h are achievable. Widespread acceptance of this technology has resulted in unique and major installations over the past few years. This paper reviews various applications - from the viewpoint of successfully proven vertical lift systems as well as the maintenance and downtime aspects. 3 refs., 9 figs.

  7. An observational study of foot lifts asymmetry during obstacle avoidance

    Directory of Open Access Journals (Sweden)

    Ujjawal Singh Tomar

    2012-01-01

    Full Text Available Background: Specific information regarding obstacle-clearance strategies used by community-dwelling young and elderly is scant in the literature, and physical barriers encountered in real-life situations have not been used in most of the studies. Aim: The aim of this study is to determine foot lift asymmetry during obstacle avoidance in young and elderly subjects. Settings and Design: This was an observational study. Materials and Methods: Thirty elderly and 30 young individuals were taken for the study. All the subjects were evaluated using different scales and foot lift asymmetry was measured on a walkway using three obstacles of different heights. Results: The mean and standard deviation (SD value of the asymmetric index of the young was 3.25±0.28 and the mean and SD value of the asymmetric index of the elderly was 3.53±0.47. The asymmetric index of the elderly population was found to be higher than that of the younger population. Conclusion: The asymmetric index of the elderly population was found to be higher than that of the younger population, though it is not clinically significant.

  8. On-line fibration measurements in lifting magnets

    International Nuclear Information System (INIS)

    Joas, H.D.

    1993-01-01

    After a solenoid pilot valve had failed to open during a functional test, all of the 17 lifting magnets of the pilot valves were removed, inspected and overhauled during the refuelling of a BWR. Some lifting magnets were found to have deposits between rod (austenitic) and guide sleeve (brass). A relative movement (hammering) between both components was the suspected cause. Measurements confirmed the assumption of a laterally hammering movement of the rods, and also a correlation between acceleration intensity and deposit thickness. Local changes of design or modification of material pairing were suggested as remedial actions. The simulation of measured operation loads was effected on a test rig by means of vibration exciter and the acceleration-time factors known from operation. This resulted in a simple design modification which reduces the impact load between rod and bearing during operation, or else in a suitable material pairing which is optimized for impact load rather than sliding load. Building-up the wear area of the rod was found to interfere least with the existing design. (orig./DG) [de

  9. Effects of squat lift training and free weight muscle training on maximum lifting load and isolinetic peak torque of young adults without impairments.

    Science.gov (United States)

    Yeung, S S; Ng, G Y

    2000-06-01

    Manual lifting is a frequent cause of back injury, and there is no evidence as to which training mode can provide the best training effect for lifting performance and muscle force. The purpose of this study was to examine the effects of a squat lift training and a free weight muscle training program on the maximum lifting load and isokinetic peak torque in subjects without known neuromuscular or musculoskeletal impairments. Thirty-six adults (20 male, 16 female) without known neuromuscular or musculoskeletal impairments participated. The subjects' mean age was 21.25 years (SD=1.16, range=20-24). Subjects were divided into 3 groups. Subjects in group 1 (n=12) performed squat lift training. Subjects in group 2 (n=12) participated in free weight resistance training of their shoulder abductors, elbow flexors, knee extensors and trunk extensors. Subjects in group 3 (n=12) served as controls. The maximum lifting load and isokinetic peak torques of the trunk extensors, knee extensors, elbow flexors, and shoulder abductors of each subject were measured before and after the study. Training was conducted on alternate days for 4 weeks, with an initial load of 80% of each subject's maximum capacity and with the load increased by 5% weekly. All groups were comparable for all measured variables before the study. After 4 weeks, subjects in groups 1 and 2 demonstrated more improvement in maximum lifting load and isokinetic peak torque of the back extensors compared with the subjects in group 3, but the 2 training groups were not different. The findings demonstrate that both squat lift and free weight resistance training are equally effective in improving the lifting load and isokinetic back extension performance of individuals without impairments.

  10. Evaluation of team lifting on work demands, workload and workers' evaluation: an observational field study.

    Science.gov (United States)

    Visser, Steven; van der Molen, Henk F; Kuijer, P Paul F M; Hoozemans, Marco J M; Frings-Dresen, Monique H W

    2014-11-01

    The objective of this study was to assess differences in work demands, energetic workload and workers' discomfort and physical effort in two regularly observable workdays in ironwork; one where loads up to 50kg were handled with two persons manually (T50) and one where loads up to 100kg were handled manually with four persons (T100). Differences between these typical workdays were assessed with an observational within-subject field study of 10 ironworkers. No significant differences were found for work demands, energetic workload or discomfort between T50 and T100 workdays. During team lifts, load mass exceeded 25kg per person in 57% (T50 workday) and 68% (T100 workday) of the lifts. Seven ironworkers rated team lifting with two persons as less physically demanding compared with lifting with four persons. When loads heavier than 25kg are lifted manually with a team, regulations of the maximum mass weight are frequently violated. Loads heavier than 25kg are frequently lifted during concrete reinforcement work and should be lifted by a team of persons. However, the field study showed that loads above 25kg are most of the time not lifted with the appropriate number of workers. Therefore, loads heavier than 25kg should be lifted mechanically. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  11. An improved method for lifting and transporting anesthetized pigs within an animal facility

    DEFF Research Database (Denmark)

    Schumacher-Petersen, Camilla; Hammelev, Karsten Pharao; Flescher, Jens Erik

    2014-01-01

    Transporting anesthetized pigs in a laboratory setting often requires strenuous manual lifting, posing a hazard to the safety of animal care personnel and to the welfare of the pigs. The authors developed an improved approach to lifting and transporting anesthetized pigs weighing up to 350 kg using...... mechanical lifts. Different equipment was used to accommodate pigs of different sizes as well as the building designs of three animal facilities. Using the lifts, anesthetized pigs are carried on sheets to maintain their comfort while being transported. The approach refines previous methods for handling...

  12. CFD Study of an Annular-Ducted Fan Lift System for VTOL Aircraft

    Directory of Open Access Journals (Sweden)

    Yun Jiang

    2015-09-01

    Full Text Available The present study aimed at assessing a novel annular-ducted fan lift system for VTOL aircraft through computational fluid dynamics (CFD simulations. The power and lift efficiency of the lift fan system in hover mode, the lift and drag in transition mode, the drag and flight speed of the aircraft in cruise mode and the pneumatic coupling of the tip turbine and jet exhaust were studied. The results show that the annular-ducted fan lift system can have higher lift efficiency compared to the rotor of the Apache helicopter; the smooth transition from vertical takeoff to cruise flight needs some extra forward thrust to overcome a low peak of drag; the aircraft with the lift fan system enclosed during cruise flight theoretically may fly faster than helicopters and tiltrotors based on aerodynamic drag prediction, due to the elimination of rotor drag and compressibility effects on the rotor blade tips; and pneumatic coupling of the tip turbine and jet exhaust of a 300 m/s velocity can provide enough moment to spin the lift fan. The CFD results provide insight for future experimental study of the annular-ducted lift fan VTOL aircraft.

  13. Approximate soil-structure interaction with separation of base mat from soil (lifting-off)

    International Nuclear Information System (INIS)

    Wolf, J.P.

    1975-01-01

    In reactor buildings having a sheild-building (outer concrete shell) with a large mass, which is particularly the case if the plant is designed for airplane crash, large over-turning moments are developed by earthquake loading. In this paper, the standard linear elastic half-space theory is used in the soil-structure interaction model. For a circular base mat, if the overturning moment exceeds the product of the normal force (dead weight minus the effect of the vertical earthquake) and one-third of the radius, then tension will occur in the area of contact, assuming distribution of stress as in the static case. For a strip foundation the same occurs if the eccentricity of the normal force exceeds a quarter of the total width. As tension is incompatible with the constitutive law of soils, the base mat will become partially separated from the foundation. Assming that only normal stresses in compression and corresponding shear stresses (friction) can occur in the area of contact, a method of analyzing soil-structure interaction including lifting-off is derived, which otherwise is based on elastic behaviour of the soil. First a rigorous iterative procedure is outlined based on (complex) dynamic influence matrices of displacements on the surface of an elastic half-space at a certain distance from a rigid disc or strip. A similar, approximate method is then developed which is used throughout the paper. As an example the dynamic response of the reactor building of a 1000 Megawatt plant to earthquake motion is calculated. The results of the analysis, including lift-off, are compared to those of the linear case. (Auth.)

  14. Functional dorsoventral symmetry in relation to lift-based swimming in the ocean sunfish Mola mola.

    Directory of Open Access Journals (Sweden)

    Yuuki Watanabe

    Full Text Available The largest (up to 2 tons and a globally distributed teleost--the ocean sunfish Mola mola--is commonly regarded as a planktonic fish because of its unusual shape including absence of caudal fin. This common view was recently questioned because the horizontal movements of the ocean sunfish tracked by acoustic telemetry were independent of ocean currents. However, direct information regarding their locomotor performance under natural conditions is still lacking. By using multi-sensor tags, we show that sunfish indeed swam continuously with frequent vertical movements at speeds of 0.4-0.7 m s(-1, which is similar to the records of other large fishes such as salmons, marlins, and pelagic sharks. The acceleration data revealed that they stroked their dorsal and anal fins synchronously (dominant frequency, 0.3-0.6 Hz to generate a lift-based thrust, as penguins do using two symmetrical flippers. Morphological studies of sunfish (mass, 2-959 kg showed that the dorsal and anal fins had similar external (symmetrical shape and identical area and internal (identical locomotory muscle mass features; however, the muscle shape differed markedly. We conclude that ocean sunfish have functional dorsoventral symmetry with regards to the non-homologous dorsal and anal fins that act as a pair of vertical hydrofoils. Although sunfish lack a swimbladder, we found that they are neutrally buoyant independent of depth because of their subcutaneous gelatinous tissue that has low density and is incompressible. Efficient lift-based swimming in conjunction with neutral buoyancy enables sunfish to travel long distances both horizontally and vertically.

  15. Fuel properties to enable lifted-flame combustion

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Eric [Ford Motor Company, Dearborn, MI (United States)

    2015-03-15

    The Fuel Properties to Enable Lifted-Flame Combustion project responded directly to solicitation DE-FOA-0000239 AOI 1A, Fuels and Lubricants for Advanced Combustion Regimes. This subtopic was intended to encompass clean and highly-efficient, liquid-fueled combustion engines to achieve extremely low engine-out nitrogen oxides (NOx) and particulate matter (PM) as a target and similar efficiency as state-of-the-art direct injection diesel engines. The intent of this project was to identify how fuel properties can be used to achieve controllable Leaner Lifted Flame Combustion (LLFC) with low NOx and PM emissions. Specifically, this project was expected to identify and test key fuel properties to enable LLFC and their compatibility with current fuel systems and to enhance combustion models to capture the effect of fuel properties on advanced combustion. Successful demonstration of LLFC may reduce the need for after treatment devices, thereby reducing costs and improving thermal efficiency. The project team consisted of key technical personnel from Ford Motor Company (FMC), the University of Wisconsin-Madison (UW), Sandia National Laboratories (SNL) and Lawrence Livermore National Laboratories (LLNL). Each partner had key roles in achieving project objectives. FMC investigated fuel properties relating to LLFC and sooting tendency. Together, FMC and UW developed and integrated 3D combustion models to capture fuel property combustion effects. FMC used these modeling results to develop a combustion system and define fuel properties to support a single-cylinder demonstration of fuel-enabled LLFC. UW investigated modeling the flame characteristics and emissions behavior of different fuels, including those with different cetane number and oxygen content. SNL led spray combustion experiments to quantify the effect of key fuel properties on combustion characteristics critical for LLFC, as well as single cylinder optical engine experiments to improve fundamental

  16. Abrasion behavior of graphite pebble in lifting pipe of pebble-bed HTR

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Ke; Su, Jiageng [Institute of Nuclear and New Energy Technology, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 10084 (China); Zhou, Hongbo [Institute of Nuclear and New Energy Technology, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 10084 (China); Chinergy Co., LTD., Beijing 100193 (China); Peng, Wei; Liu, Bing [Institute of Nuclear and New Energy Technology, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 10084 (China); Yu, Suyun, E-mail: suyuan@tsinghua.edu.cn [Center for Combustion Energy, The Key Laboratory for Thermal Science and Power Engineering, Ministry of Educations, Tsinghua University, Beijing 10084 (China)

    2015-11-15

    Highlights: • Quantitative determination of abrasion rate of graphite pebbles in different lifting velocities. • Abrasion behavior of graphite pebble in helium, air and nitrogen. • In helium, intensive collisions caused by oscillatory motion result in more graphite dust production. - Abstract: A pebble-bed high-temperature gas-cooled reactor (pebble-bed HTR) uses a helium coolant, graphite core structure, and spherical fuel elements. The pebble-bed design enables on-line refueling, avoiding refueling shutdowns. During circulation process, the pebbles are lifted pneumatically via a stainless steel lifting pipe and reinserted into the reactor. Inevitably, the movement of the fuel elements as they recirculate in the reactor produces graphite dust. Mechanical wear is the primary source of graphite dust production. Specifically, the sources are mechanisms of pebble–pebble contact, pebble–wall (structural graphite) contact, and fuel handling (pebble–metal abrasion). The key contribution to graphite dust production is from the fuel handling system, particularly from the lifting pipe. During pneumatic lift, graphite pebbles undergo multiple collisions with the stainless steel lifting pipe, thereby causing abrasion of the graphite pebbles and producing graphite dust. The present work explored the abrasion behavior of graphite pebble in the lifting pipe by measuring the abrasion rate at different lifting velocities. The abrasion rate of the graphite pebble in helium was found much higher than those in air and nitrogen. This gas environment effect could be explained by either tribology behavior or dynamic behavior. Friction testing excluded the possibility of tribology reason. The dynamic behavior of the graphite pebble was captured by analysis of the audio waveforms during pneumatic lift. The analysis results revealed unique dynamic behavior of the graphite pebble in helium. Oscillation and consequently intensive collisions occur during pneumatic lift, causing

  17. Airfoil design: Finding the balance between design lift and structural stiffness

    International Nuclear Information System (INIS)

    Bak, Christian; Gaudern, Nicholas; Zahle, Frederik; Vronsky, Tomas

    2014-01-01

    When upscaling wind turbine blades there is an increasing need for high levels of structural efficiency. In this paper the relationships between the aerodynamic characteristics; design lift and lift-drag ratio; and the structural characteristics were investigated. Using a unified optimization setup, airfoils were designed with relative thicknesses between 18% and 36%, a structural box height of 85% of the relative thickness, and varying box widths in chordwise direction between 20% and 40% of the chord length. The results from these airfoil designs showed that for a given flapwise stiffness, the design lift coefficient increases if the box length reduces and at the same time the relative thickness increases. Even though the conclusions are specific to the airfoil design approach used, the study indicated that an increased design lift required slightly higher relative thickness compared to airfoils with lower design lift to maintain the flapwise stiffness. Also, the study indicated that the lift-drag ratio as a function of flapwise stiffness was relatively independent of the airfoil design with a tendency that the lift-drag ratio decreased for large box lengths. The above conclusions were supported by an analysis of the three airfoil families Riso-C2, DU and FFA, where the lift-drag ratio as a function of flapwise stiffness was decreasing, but relatively independent of the airfoil design, and the design lift coefficient was varying depending on the design philosophy. To make the analysis complete also design lift and lift- drag ratio as a function of edgewise and torsional stiffness were shown

  18. Canadian East Coast offshore petroleum industry safe lifting practices respecting offshore pedestal cranes, offshore containers, loose gear, other lifting devices, and operational best practices : standard practices

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-11-15

    This document was developed by a working group with representatives from the petroleum industry, the Offshore Petroleum Boards and Certifying Authorities. It outlines industry best practices for operators responsible for the management, planning and execution of offshore lifting operations. Its purpose is to assist in the interpretation of applicable legislation and standards. Considered within the practice are safe design requirements, manufacture, certification, testing, maintenance and inspection requirements for pedestal cranes, offshore containers, loose gear and lifting devices. Operational best practices for lifting operations are also included along with a section that identifies additional requirements for personnel lifting operations, including personnel transfers by crane and man-riding operations. 82 refs., 2 tabs., 4 figs., 3 appendices.

  19. Systematic characterization of structural, dynamical and electrical properties of dust devils and implications for dust lifting processes

    Science.gov (United States)

    Franzese, Gabriele; Esposito, Francesca; Lorenz, Ralph D.; Popa, Ciprian; Silvestro, Simone; Deniskina, Natalia; Cozzolino, Fabio

    2017-04-01

    Dust devils are convective vortices able to lift sand and dust grains from the soil surface, even in conditions of low wind speed environment. They have been observed not only on Earth but also on other planets of the solar system; in particular, they are largely studied on Mars. Indeed, the contribution of the dust devils to the Martian climate is a highly debated question. In order to investigate this topic, it is important to understand the nature of the dust lifting mechanism by the vortex and characterize the induced electric field. As part of the development process of DREAMS, the meteorological station on board the Schiapparelli lander of the ExoMars 2016 mission, and of the Dust complex package of the ExoMars 2020 mission, we performed various field campaigns in the Sahara desert (Tafilalt region, Morocco). We deployed a fully equipped meteorological station and, during the 2014 summer, we observed three months of dust devils activity, collecting almost six hundreds events. For each dust devil, we monitored the horizontal wind speed and direction, the vertical wind speed, the pressure drop due to the vortex core, the temperature, the induced electric field and the concentration of dust lifted. This data set is unique in literature and represents up to now the most comprehensive one available for the dusty convective vortices. Here we will present the analysis of the Moroccan data with particular emphasis on the study of the atmospheric electric field variations due to the passage of the vortices. The distribution of the vortex parameters (wind speed and direction, pressure, E-field and dust lifted) are showed and compared, when possible, to the ones observed by the Martian surveys. The connection between the E-field and the other parameters will be presented. In the terrestrial environment, the development of the convective vortices is restricted by the presence of the vegetation and of the urban areas, hence dust devils can impact the climate only on local

  20. Prediction of Peak Back Compressive Forces as a Function of Lifting Speed and Compressive Forces at Lift Origin and Destination - A Pilot Study

    Directory of Open Access Journals (Sweden)

    Kasey O. Greenland

    2011-09-01

    Conclusion: SODA under-predict both static and dynamic peak back-compressive force values. Peak values are highly predictable and could be readily determined using back-compressive force assessments at the origin and destination of a lifting task. This could be valuable for enhancing job design and analysis in the workplace and for large-scale studies where a full analysis of each lifting task is not feasible.

  1. A Survey of Methods for Gas-Lift Optimization

    Directory of Open Access Journals (Sweden)

    Kashif Rashid

    2012-01-01

    Full Text Available This paper presents a survey of methods and techniques developed for the solution of the continuous gas-lift optimization problem over the last two decades. These range from isolated single-well analysis all the way to real-time multivariate optimization schemes encompassing all wells in a field. While some methods are clearly limited due to their neglect of treating the effects of inter-dependent wells with common flow lines, other methods are limited due to the efficacy and quality of the solution obtained when dealing with large-scale networks comprising hundreds of difficult to produce wells. The aim of this paper is to provide an insight into the approaches developed and to highlight the challenges that remain.

  2. Leveraging Parallel Data Processing Frameworks with Verified Lifting

    Directory of Open Access Journals (Sweden)

    Maaz Bin Safeer Ahmad

    2016-11-01

    Full Text Available Many parallel data frameworks have been proposed in recent years that let sequential programs access parallel processing. To capitalize on the benefits of such frameworks, existing code must often be rewritten to the domain-specific languages that each framework supports. This rewriting–tedious and error-prone–also requires developers to choose the framework that best optimizes performance given a specific workload. This paper describes Casper, a novel compiler that automatically retargets sequential Java code for execution on Hadoop, a parallel data processing framework that implements the MapReduce paradigm. Given a sequential code fragment, Casper uses verified lifting to infer a high-level summary expressed in our program specification language that is then compiled for execution on Hadoop. We demonstrate that Casper automatically translates Java benchmarks into Hadoop. The translated results execute on average 3.3x faster than the sequential implementations and scale better, as well, to larger datasets.

  3. Development of parietal bone surrogates for parietal graft lift training

    Directory of Open Access Journals (Sweden)

    Hollensteiner Marianne

    2016-09-01

    Full Text Available Currently the surgical training of parietal bone graft techniques is performed on patients or specimens. Commercially available bone models do not deliver realistic haptic feedback. Thus customized parietal skull surrogates were developed for surgical training purposes. Two human parietal bones were used as reference. Based on the measurement of insertion forces of drilling, milling and saw procedures suitable material compositions for molding cortical and cancellous calvarial layers were found. Artificial skull caps were manufactured and tested. Additionally microtomograpy images of human and artificial parietal bones were performed to analyze outer table and diploe thicknesses. Significant differences between human and artificial skulls were not detected with the mechanical procedures tested. Highly significant differences were found for the diploe thickness values. In conclusion, an artificial bone has been created, mimicking the properties of human parietal bone thus being suitable for tabula externa graft lift training.

  4. A general theory for gauge-free lifting

    International Nuclear Information System (INIS)

    Morrison, P. J.

    2013-01-01

    A theory for lifting equations of motion for charged particle dynamics, subject to given electromagnetic like forces, up to a gauge-free system of coupled Hamiltonian Vlasov-Maxwell like equations is given. The theory provides very general expressions for the polarization and magnetization vector fields in terms of the particle dynamics description of matter. Thus, as is common in plasma physics, the particle dynamics replaces conventional constitutive relations for matter. Several examples are considered including the usual Vlasov-Maxwell theory, a guiding center kinetic theory, Vlasov-Maxwell theory with the inclusion of spin, and a Vlasov-Maxwell theory with the inclusion of Dirac's magnetic monopoles. All are shown to be Hamiltonian field theories and the Jacobi identity is proven directly.

  5. Adaptive nonseparable vector lifting scheme for digital holographic data compression.

    Science.gov (United States)

    Xing, Yafei; Kaaniche, Mounir; Pesquet-Popescu, Béatrice; Dufaux, Frédéric

    2015-01-01

    Holographic data play a crucial role in recent three-dimensional imaging as well as microscopic applications. As a result, huge amounts of storage capacity will be involved for this kind of data. Therefore, it becomes necessary to develop efficient hologram compression schemes for storage and transmission purposes. In this paper, we focus on the shifted distance information, obtained by the phase-shifting algorithm, where two sets of difference data need to be encoded. More precisely, a nonseparable vector lifting scheme is investigated in order to exploit the two-dimensional characteristics of the holographic contents. Simulations performed on different digital holograms have shown the effectiveness of the proposed method in terms of bitrate saving and quality of object reconstruction.

  6. Ontogeny of lift and drag production in ground birds.

    Science.gov (United States)

    Heers, Ashley M; Tobalske, Bret W; Dial, Kenneth P

    2011-03-01

    The juvenile period is often a crucial interval for selective pressure on locomotor ability. Although flight is central to avian biology, little is known about factors that limit flight performance during development. To improve understanding of flight ontogeny, we used a propeller (revolving wing) model to test how wing shape and feather structure influence aerodynamic performance during development in the precocial chukar partridge (Alectoris chukar, 4 to >100 days post hatching). We spun wings in mid-downstroke posture and measured lift (L) and drag (D) using a force plate upon which the propeller assembly was mounted. Our findings demonstrate a clear relationship between feather morphology and aerodynamic performance. Independent of size and velocity, older wings with stiffer and more asymmetrical feathers, high numbers of barbicels and a high degree of overlap between barbules generate greater L and L:D ratios than younger wings with flexible, relatively symmetrical and less cohesive feathers. The gradual transition from immature feathers and drag-based performance to more mature feathers and lift-based performance appears to coincide with ontogenetic transitions in locomotor capacity. Younger birds engage in behaviors that require little aerodynamic force and that allow D to contribute to weight support, whereas older birds may expand their behavioral repertoire by flapping with higher tip velocities and generating greater L. Incipient wings are, therefore, uniquely but immediately functional and provide flight-incapable juveniles with access to three-dimensional environments and refugia. Such access may have conferred selective advantages to theropods with protowings during the evolution of avian flight.

  7. Prediction of peak back compressive forces as a function of lifting speed and compressive forces at lift origin and destination - a pilot study.

    Science.gov (United States)

    Greenland, Kasey O; Merryweather, Andrew S; Bloswick, Donald S

    2011-09-01

    To determine the feasibility of predicting static and dynamic peak back-compressive forces based on (1) static back compressive force values at the lift origin and destination and (2) lifting speed. Ten male subjects performed symmetric mid-sagittal floor-to-shoulder, floor-to-waist, and waist-to-shoulder lifts at three different speeds (slow, medium, and fast), and with two different loads (light and heavy). Two-dimensional kinematics and kinetics were captured. Linear regression analyses were used to develop prediction equations, the amount of predictability, and significance for static and dynamic peak back-compressive forces based on a static origin and destination average (SODA) back-compressive force. Static and dynamic peak back-compressive forces were highly predicted by the SODA, with R(2) values ranging from 0.830 to 0.947. Slopes were significantly different between slow and fast lifting speeds (p assessments at the origin and destination of a lifting task. This could be valuable for enhancing job design and analysis in the workplace and for large-scale studies where a full analysis of each lifting task is not feasible.

  8. 2005 ACGIH Lifting TLV: Employee-Friendly Presentation and Guidance for Professional Judgment

    Energy Technology Data Exchange (ETDEWEB)

    Splittstoesser, Riley [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); O' Farrell, Daniel Edward [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hill, John [Savannah River Site (SRS), Aiken, SC (United States); McMahon, Terrence [SLAC National Accelerator Lab., Menlo Park, CA (United States); Sastry, Nikhil [SLAC National Accelerator Lab., Menlo Park, CA (United States); Tiemeier, Mark [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2017-05-22

    The American Council of Governmental Industrial Hygienists (ACGIH) Lifting Threshold Limit Values (TLVs) provide a tool to reduce incidence of low back and shoulder injuries. However, application of the TLV is too complicated for floor-level workers and relies on professional judgment to assess commonly encountered tasks. This paper presents an Employee-Friendly Simplified Format of the TLV that has been adapted from Table 1 of the Lifting TLV presented in the 2005 TLVs and BEIs Based on the Documentation of the Threshold Limit Values for Chemical Substances and Physical Agents & Biological Exposure Indices. This simplified format can be employed by floor-level workers to self-assess lifting tasks. The Ergonomics Project Team also provides research-based guidance for applying professional judgment consistent with standard industry practice: Extended Work Shifts – Reduce weight by 20% for shifts lasting 8 to 12 hours; Constrained Lower Body Posture – Reduce weight by 25% when lifting in such postures; Infrequently Performed LiftsLift up to 15 lbs. ≤3 lifts per hour within the zones marked “No safe limit for repetitive lifting” in the TLVs Table 1; Asymmetry beyond 30° – Reduce weight by 10 lbs. for lifts with up to 60° asymmetry from sagittal plane.

  9. 75 FR 17754 - Certificate of Alternative Compliance for the Lift Boat GARY CHIASSON ELEVATOR

    Science.gov (United States)

    2010-04-07

    ... Compliance for the Lift Boat GARY CHIASSON ELEVATOR AGENCY: Coast Guard, DHS. ACTION: Notice. SUMMARY: The... CHIASSON ELEVATOR as required by 33 U.S.C. 1605(c) and 33 CFR 81.18. DATES: The Certificate of Alternate... for the lift boat GARY CHIASSON ELEVATOR. The Certificate of Alternative Compliance permits the...

  10. 49 CFR 571.403 - Standard No. 403; Platform lift systems for motor vehicles.

    Science.gov (United States)

    2010-10-01

    ... the mobility aid or passenger rests while being raised or lowered. Platform lift means a level change... from ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. S5.6... lifts suitable for installation on buses, school buses, and MPVs other than motor homes with a GVWR...

  11. Effects of the European Community directive on lifting and handling practice.

    Science.gov (United States)

    Docker, S M

    1993-07-01

    The new legislation on lifting and handling requires the application of ergonomic principles to manual handling operations. A written assessment is required for all unavoidable manual handling operations which involve the risk of injury to employees. Employers are now expected to provide equipment to enable staff to avoid lifting heavy loads.

  12. The control of equilibrium in bimanual, whole-body lifting tasks : a biomechanical approach

    NARCIS (Netherlands)

    Commissaris, D.A.C.M.

    1997-01-01

    The issues addressed in this thesis concern the control of equilibrium in a bimanual, wholebody lifting task. This task comprises the forward bending of the trunk and the lowering of the whole body to grasp an object with two hands, followed by the lifting of the object to waist or chest level.

  13. Method of determining the depth of gas entry into the lifter of a gas lift well

    Energy Technology Data Exchange (ETDEWEB)

    Mishalov, N F; Popov, V A

    1981-01-01

    A method is proposed for determining the depth of gas entry into the lifter of a gas lift well, based on the data for measuring downhole and effective pressures. The method is used when analyzing and selecting operating conditions for gas lift wells at the Pravdinsk field.

  14. 76 FR 15798 - Special Conditions: Boeing 747-468, Installation of a Medical Lift

    Science.gov (United States)

    2011-03-22

    ... platform is driven by two redundant electrical motors, mounted to the rear wall, between the struts. A... DURING TAXI, TAKEOFF, LANDING, OR TURBULENCE. c. AN APPROVED MEDICAL STRETCHER OR WHEELCHAIR MUST BE... the lift. c. Stow the lift for non-operation such as during TTL and turbulence. d. Operate the...

  15. 78 FR 3356 - Airworthiness Directives; Various Aircraft Equipped With Wing Lift Struts

    Science.gov (United States)

    2013-01-16

    ...) of this AD, inspect the wing lift strut forks for cracks using magnetic particle procedures, such as... for Non-destructive Testing, or MIL-STD-410. (i) If no external corrosion is found on any wing lift..., the surface should be sanded or polished smooth before testing to assure a consistent and smooth...

  16. Hydraulic lift in a neotropical savanna: experimental manipulation and model simulations

    Science.gov (United States)

    Fabian G. Scholz; Sandra J. Bucci; William A. Hoffmann; Frederick C. Meinzer; Guillermo Goldstein

    2010-01-01

    The objective of this study was to assess the magnitude of hydraulic lift in Brazilian savannas (Cerrado) and to test the hypothesis that hydraulic lift by herbaceous plants contributes substantially to slowing the decline of water potential and water storage in the upper soil layers during the dry season. To this effect, field observations of soil water content and...

  17. Trunk muscle activation and low back loading in lifting in the absence of load knowledge

    NARCIS (Netherlands)

    Looze, M.P. de; Steenhuizen, S.; Boeken-Kruger, M.C.; Baten, C.T.M.; Kingma, I.; Dieën, J.H. van

    2000-01-01

    People who know the actual mass of an object to be lifted normally prepare themselves before attempting a lift to control the movement and to minimize low back loading. In this study, the trunk muscular reactions and low back torque were investigated in the situation in which the individual did not

  18. Lifting an unexpectedly heavy object : the effects on low-back loading and balance loss

    NARCIS (Netherlands)

    van der Burg, J C; van Dieën, J H; Toussaint, H M

    OBJECTIVE: This study evaluates the effects of lifting an unexpectedly heavy object on low-back loading and loss of balance. BACKGROUND: It is often suggested that lifting an unexpectedly heavy object may be a major risk factor for low-back pain. This may lead to an increase in muscle activation,

  19. Optimisation of a novel trailing edge concept for a high lift device

    CSIR Research Space (South Africa)

    Botha, JDM

    2015-01-01

    Full Text Available This study aimed to observe the effect of a novel concept (referred to as the flap extension) implemented on the leading edge of the flap of a three element high lift device. The high lift device, consisting of a flap, main element and slat...

  20. Computer simulation of viscous fingering in a lifting Hele-Shaw cell

    Indian Academy of Sciences (India)

    We simulate viscous fingering generated by separating two plates with a constant force, in a lifting Hele-Shaw cell. Variation in the patterns for different fluid viscosity and lifting force is studied. Viscous fingering is strongly affected by anisotropy. We report a computer simulation study of fingering patterns, where circular or ...

  1. Development of Advanced High Lift Leading Edge Technology for Laminar Flow Wings

    Science.gov (United States)

    Bright, Michelle M.; Korntheuer, Andrea; Komadina, Steve; Lin, John C.

    2013-01-01

    This paper describes the Advanced High Lift Leading Edge (AHLLE) task performed by Northrop Grumman Systems Corporation, Aerospace Systems (NGAS) for the NASA Subsonic Fixed Wing project in an effort to develop enabling high-lift technology for laminar flow wings. Based on a known laminar cruise airfoil that incorporated an NGAS-developed integrated slot design, this effort involved using Computational Fluid Dynamics (CFD) analysis and quality function deployment (QFD) analysis on several leading edge concepts, and subsequently down-selected to two blown leading-edge concepts for testing. A 7-foot-span AHLLE airfoil model was designed and fabricated at NGAS and then tested at the NGAS 7 x 10 Low Speed Wind Tunnel in Hawthorne, CA. The model configurations tested included: baseline, deflected trailing edge, blown deflected trailing edge, blown leading edge, morphed leading edge, and blown/morphed leading edge. A successful demonstration of high lift leading edge technology was achieved, and the target goals for improved lift were exceeded by 30% with a maximum section lift coefficient (Cl) of 5.2. Maximum incremental section lift coefficients ( Cl) of 3.5 and 3.1 were achieved for a blown drooped (morphed) leading edge concept and a non-drooped leading edge blowing concept, respectively. The most effective AHLLE design yielded an estimated 94% lift improvement over the conventional high lift Krueger flap configurations while providing laminar flow capability on the cruise configuration.

  2. Group Lifting Structures For Multirate Filter Banks, II: Linear Phase Filter Banks

    Energy Technology Data Exchange (ETDEWEB)

    Brislawn, Christopher M [Los Alamos National Laboratory

    2008-01-01

    The theory of group lifting structures is applied to linear phase lifting factorizations for the two nontrivial classes of two-channel linear phase perfect reconstruction filter banks, the whole-and half-sample symmetric classes. Group lifting structures defined for the reversible and irreversible classes of whole-and half-sample symmetric filter banks are shown to satisfy the hypotheses of the uniqueness theorem for group lifting structures. It follows that linear phase lifting factorizations of whole-and half-sample symmetric filter banks are therefore independent of the factorization methods used to compute them. These results cover the specification of user-defined whole-sample symmetric filter banks in Part 2 of the ISO JPEG 2000 standard.

  3. Effects of stern-foil submerged elevation on the lift and drag of a hydrofoil craft

    Science.gov (United States)

    Suastika, K.; Apriansyah

    2018-03-01

    Effects of the stern-foil submerged elevation on the lift and drag of a hydrofoil craft are studied by using computational fluid dynamics (CFD) and by considering three alternative stern-foil submerged elevations. The submerged elevation of the front foil is kept constant in all the alternatives. From among the alternatives, the deepest stern-foil placement results in the highest stern-foil lift with the highest foil’s lift-to-drag ratio. However, considering the lift-to-drag ratio of the whole foil-strut-hull system, the shallowest stern-foil placement results in the highest lift-to-drag ratio. The struts and the foil’s submerged elevation significantly affects the drag of the whole foil-strut-hull system.

  4. Modeling of load lifting process with unknown center of gravity position

    Science.gov (United States)

    Kamanin, Y. N.; Zhukov, M. I.; Panichkin, A. V.; Redelin, R. A.

    2018-03-01

    The article proposes a new type of lifting beams that allows one to lift loads where the position of the center of gravity is unknown beforehand. The benefit of implementing this type of traverse is confirmed by the high demand for this product from the industrial enterprises and lack of their availability on the market. In conducted studies, the main kinematic and dynamic dependencies of the load lifting process with an unknown position of the center of gravity were described allowing for design and verification calculations of the traverse with flexible slings and an adjustable bail to be carried out. The obtained results can be useful to engineers and employees of enterprises engaged in the design and manufacturing of the lifting equipment and scientists doing research in “Carrying and lifting machines”.

  5. Cracked lifting lug welds on ten-ton UF{sub 6} cylinders

    Energy Technology Data Exchange (ETDEWEB)

    Dorning, R.E. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

    1991-12-31

    Ten-ton, Type 48X, UF{sub 6} cylinders are used at the Portsmouth Gaseous Diffusion Plant to withdraw enriched uranium hexafluoride from the cascade, transfer enriched uranium hexafluoride to customer cylinders, and feed enriched product to the cascade. To accomplish these activities, the cylinders are lifted by cranes and straddle carriers which engage the cylinder lifting lugs. In August of 1988, weld cracks on two lifting lugs were discovered during preparation to lift a cylinder. The cylinder was rejected and tagged out, and an investigating committee formed to determine the cause of cracking and recommend remedial actions. Further investigation revealed the problem may be general to this class of cylinder in this use cycle. This paper discusses the actions taken at the Portsmouth site to deal with the cracked lifting lug weld problem. The actions include inspection activities, interim corrective actions, metallurgical evaluation of cracked welds, weld repairs, and current monitoring/inspection program.

  6. Application of the New Propulsion Theory to the Design of Propellers. Comparison with the Lifting Line Theory (Aplicacion de la Nueva Teoria de la Impulsion al Diseno de Propulsores. Comparacion con la Teoria de las Lineas Sustentadoras),

    Science.gov (United States)

    1983-11-07

    obtained with the lifting line theory is very sensitive to the type of radial distribution law of circulation. In the past, especially for theoretical...I. Bacquerizo Briones, "Utilidad de la educacion de Poincare para el proyecto y analisis de propulsores con valores finitos de la circulacion en el

  7. Cooperative control system of the floating cranes for the dual lifting

    Directory of Open Access Journals (Sweden)

    Mihee Nam

    2018-01-01

    Full Text Available This paper proposes a dual lifting and its cooperative control system with two different kinds of floating cranes. The Mega-erection and Giga-erection in the ship building are used to handle heavier and wider blocks and modules as ships and off-shore platforms are enlarged. However, there is no equipment to handle such Tera-blocks. In order to overcome the limit on performance of existing floating cranes, the dual lifting is proposed in this research. In the dual lifting, two floating cranes are well-coordinated to add up the lift capabilities of both cranes without any loss such that virtually a single crane is lifting, maneuvering and unloading. Two main constraints for the dual lifting are as follows: First, two barges of floating cranes should be constrained as a rigid body not to cause a relative motion between two barges and main hooks of the two cranes should be controlled as main hooks of a single crane. In order words, it is necessary to develop the cooperative control of two floating cranes in order to sustain a center of gravity of the module and minimize the tilting angle during the lifting and unloading by the two floating cranes. Two floating cranes are handled as a master-slave system. The master crane is able to gather information about all working conditions and make a decision to control the individual hook speed, which communicates the slave crane by TCP/IP. The developed control system has been embedded in the real floating crane systems and the dual lifting has been demonstrated five times at SHI shipyard in 2015. The moving angles of the lifting module are analyzed and verified to be suitable for hoisting control. It is verified that the dual lifting can be applied for many heavier and wider blocks and modules to shorten the construction time of ships and off-shore platforms.

  8. Wingtip Vortices and Free Shear Layer Interaction in the Vicinity of Maximum Lift to Drag Ratio Lift Condition

    Science.gov (United States)

    Memon, Muhammad Omar

    Cost-effective air-travel is something everyone wishes for when it comes to booking flights. The continued and projected increase in commercial air travel advocates for energy efficient airplanes, reduced carbon footprint, and a strong need to accommodate more airplanes into airports. All of these needs are directly affected by the magnitudes of drag these aircraft experience and the nature of their wingtip vortex. A large portion of the aerodynamic drag results from the airflow rolling from the higher pressure side of the wing to the lower pressure side, causing the wingtip vortices. The generation of this particular drag is inevitable however, a more fundamental understanding of the phenomenon could result in applications whose benefits extend much beyond the relatively minuscule benefits of commonly-used winglets. Maximizing airport efficiency calls for shorter intervals between takeoffs and landings. Wingtip vortices can be hazardous for following aircraft that may fly directly through the high-velocity swirls causing upsets at vulnerably low speeds and altitudes. The vortex system in the near wake is typically more complex since strong vortices tend to continue developing throughout the near wake region. Several chord lengths distance downstream of a wing, the so-called fully rolled up wing wake evolves into a combination of a discrete wingtip vortex pair and a free shear layer. Lift induced drag is generated as a byproduct of downwash induced by the wingtip vortices. The parasite drag results from a combination of form/pressure drag and the upper and lower surface boundary layers. These parasite effects amalgamate to create the free shear layer in the wake. While the wingtip vortices embody a large portion of the total drag at lifting angles, flow properties in the free shear layer also reveal their contribution to the aerodynamic efficiency of the aircraft. Since aircraft rarely cruise at maximum aerodynamic efficiency, a better understanding of the balance

  9. Drag and Lift Estimation from 3-D Velocity Field Data Measured by Multi-Plane Stereo PIV

    OpenAIRE

    加藤, 裕之; 松島, 紀佐; 上野, 真; 小池, 俊輔; 渡辺, 重哉; Kato, Hiroyuki; Matsushima, Kisa; Ueno, Makoto; Koike, Shunsuke; Watanabe, Shigeya

    2013-01-01

    For airplane design, it is crucial to have tools that can accurately predict airplane drag and lift. Usually drag and lift prediction methods are force measurement using wind tunnel balance. Unfortunately, balance data do not provide information contribution of airplane to components to drag and lift for more precise and competitive airplane design. To obtain such information, a wake integration method for use drag and lift estimation was developed for use in wake survey data analysis. Wake s...

  10. Analysis of offshore platforms lifting with fixed pile structure type (fixed platform) based on ASD89

    Science.gov (United States)

    Sugianto, Agus; Indriani, Andi Marini

    2017-11-01

    Platform construction GTS (Gathering Testing Sattelite) is offshore construction platform with fix pile structure type/fixed platform functioning to support the mining of petroleum exploitation. After construction fabrication process platform was moved to barges, then shipped to the installation site. Moving process is generally done by pull or push based on construction design determined when planning. But at the time of lifting equipment/cranes available in the work area then the moving process can be done by lifting so that moving activity can be implemented more quickly of work. This analysis moving process of GTS platform in a different way that is generally done to GTS platform types by lifting using problem is construction reinforcement required, so the construction can be moved by lifting with analyzing and checking structure working stress that occurs due to construction moving process by lifting AISC code standard and analysis using the SAP2000 structure analysis program. The analysis result showed that existing condition cannot be moved by lifting because stress ratio is above maximum allowable value that is 0.950 (AISC-ASD89). Overstress occurs on the member 295 and 324 with stress ratio value 0.97 and 0.95 so that it is required structural reinforcement. Box plate aplication at both members so that it produces stress ratio values 0.78 at the member 295 and stress ratio of 0.77 at the member 324. These results indicate that the construction have qualified structural reinforcement for being moved by lifting.

  11. Study of lifting operation of a tripod foundation for offshore wind turbine

    Science.gov (United States)

    Zhu, H.; Li, L.; Ong, M. C.

    2017-12-01

    This study addresses numerical analysis of the installation of a tripod foundation using a heavy lift vessel (HLV). Limiting sea states are firstly predicted in the frequency domain based on crane tip vertical motions using linear transfer functions. Then, numerical modelling and simulations are carried out in the time domain to analyse the coupled dynamic system taking into consideration of the nonlinearities of the system. In time-domain analysis, two lifting phases are brought into focus, i.e., the lift-off and the lowering phases. For the lift-off phase, two scenarios are considered, i.e., lift-off from the own deck of the HLV and lift-off from a transport barge. Moreover, comparative studies using two types of installation vessels, a floating vessel and a Jack-up, are investigated for the lowering process. Critical responses including the motions of the tripod and the lift wire tensions are presented and compared under various environmental and loading conditions.

  12. On the Estimation of Time Dependent Lift of a European Starling (Sturnus vulgaris during Flapping Flight.

    Directory of Open Access Journals (Sweden)

    Oksana Stalnov

    Full Text Available We study the role of unsteady lift in the context of flapping wing bird flight. Both aerodynamicists and biologists have attempted to address this subject, yet it seems that the contribution of unsteady lift still holds many open questions. The current study deals with the estimation of unsteady aerodynamic forces on a freely flying bird through analysis of wingbeat kinematics and near wake flow measurements using time resolved particle image velocimetry. The aerodynamic forces are obtained through two approaches, the unsteady thin airfoil theory and using the momentum equation for viscous flows. The unsteady lift is comprised of circulatory and non-circulatory components. Both approaches are presented over the duration of wingbeat cycles. Using long-time sampling data, several wingbeat cycles have been analyzed in order to cover both the downstroke and upstroke phases. It appears that the unsteady lift varies over the wingbeat cycle emphasizing its contribution to the total lift and its role in power estimations. It is suggested that the circulatory lift component cannot assumed to be negligible and should be considered when estimating lift or power of birds in flapping motion.

  13. On the Estimation of Time Dependent Lift of a European Starling (Sturnus vulgaris) during Flapping Flight.

    Science.gov (United States)

    Stalnov, Oksana; Ben-Gida, Hadar; Kirchhefer, Adam J; Guglielmo, Christopher G; Kopp, Gregory A; Liberzon, Alexander; Gurka, Roi

    2015-01-01

    We study the role of unsteady lift in the context of flapping wing bird flight. Both aerodynamicists and biologists have attempted to address this subject, yet it seems that the contribution of unsteady lift still holds many open questions. The current study deals with the estimation of unsteady aerodynamic forces on a freely flying bird through analysis of wingbeat kinematics and near wake flow measurements using time resolved particle image velocimetry. The aerodynamic forces are obtained through two approaches, the unsteady thin airfoil theory and using the momentum equation for viscous flows. The unsteady lift is comprised of circulatory and non-circulatory components. Both approaches are presented over the duration of wingbeat cycles. Using long-time sampling data, several wingbeat cycles have been analyzed in order to cover both the downstroke and upstroke phases. It appears that the unsteady lift varies over the wingbeat cycle emphasizing its contribution to the total lift and its role in power estimations. It is suggested that the circulatory lift component cannot assumed to be negligible and should be considered when estimating lift or power of birds in flapping motion.

  14. Simulation of temperature-pressure profiles and wax deposition in gas-lift wells

    Directory of Open Access Journals (Sweden)

    Sevic Snezana

    2017-01-01

    Full Text Available Gas-lift is an artificial lift method in which gas is injected down the tubing- -casing annulus and enters the production tubing through the gas-lift valves to reduce the hydrostatic pressure of the formation fluid column. The gas changes pressure, temperature and fluid composition profiles throughout the production tubing string. Temperature and pressure drop along with the fluid composition changes throughout the tubing string can lead to wax, asphaltenes and inorganic salts deposition, increased emulsion stability and hydrate formation. This paper presents a new model that can sucesfully simulate temperature and pressure profiles and fluid composition changes in oil well that operates by means of gas-lift. This new model includes a pipe-in-pipe segment (production tubing inside production casing, countercurrent flow of gas-lift gas and producing fluid, heat exchange between gas-lift gas and the surrounding ambient – ground; and gas-lift gas with the fluid in the tubing. The model enables a better understanding of the multiphase fluid flow up the production tubing. Model was used to get insight into severity and locations of wax deposition. The obtained information on wax deposition can be used to plan the frequency and depth of wax removing operations. Model was developed using Aspen HYSYS software.

  15. The influence of individual and organisational factors on nurses' behaviour to use lifting devices in healthcare.

    Science.gov (United States)

    Koppelaar, E; Knibbe, J J; Miedema, H S; Burdorf, A

    2013-07-01

    This study evaluates the influence of individual and organisational factors on nurses' behaviour to use lifting devices in healthcare. Interviews among nurses were conducted to collect individual characteristics and to establish their behaviour regarding lifting devices use. Organisational factors were collected by questionnaires and walk-through-surveys, comprising technical facilities, organisation of care, and management-efforts. Generalised-Estimating-Equations for repeated measurements were used to estimate determinants of nurses' behaviour. Important determinants of nurses' behaviour to use lifting devices were knowledge of workplace procedures (OR = 5.85), strict guidance on required lifting devices use (OR = 2.91), and sufficient lifting devices (OR = 1.92). Management-support and supportive-management-climate were associated with these determinants. Since nurses' behaviour to use lifting devices is influenced by factors at different levels, studies in ergonomics should consider how multi-level factors impact each other. An integral approach, addressing individual and organisational levels, is necessary to facilitate appropriate implementation of ergonomic interventions, like lifting devices. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. Functional residual capacity increase during laparoscopic surgery with abdominal wall lift

    Directory of Open Access Journals (Sweden)

    Hiroshi Ueda

    Full Text Available Abstract Background and objectives: The number of laparoscopic surgeries performed is increasing every year and in most cases the pneumoperitoneum method is used. One alternative is the abdominal wall lifting method and this study was undertaken to evaluate changes of functional residual capacity during the abdominal wall lift procedure. Methods: From January to April 2013, 20 patients underwent laparoscopic cholecystectomy at a single institution. All patients were anesthetized using propofol, remifentanil and rocuronium. FRC was measured automatically by Engstrom Carestation before the abdominal wall lift and again 15 minutes after the start of the procedure. Results: After abdominal wall lift, there was a significant increase in functional residual capacity values (before abdominal wall lift 1.48 × 103 mL, after abdominal wall lift 1.64 × 103 mL (p < 0.0001. No complications such as desaturation were observed in any patient during this study. Conclusions: Laparoscopic surgery with abdominal wall lift may be appropriate for patients who have risk factors such as obesity and respiratory disease.

  17. Lift, drag, and guidance forces on alternating polarity magnets, using loop guideways

    International Nuclear Information System (INIS)

    Lindenbaum, S.D.; Lee, M.S.

    1975-01-01

    Exact solutions of track current, lift force, and drag force, together with their velocity dependence, have been computed for a vehicle carrying a finite number of fixed current alternating polarity superconducting magnets, suspended at various heights over structured track guideways of the single- and double-loop (''null'') types. Results for the double-loop case are compared with those of a previously reported approximate analysis. The analytical method is then applied to a study of a low-drag guidance loop guideway which is integrable with lift loop guideways utilizing a common set of vehicle magnets. Solutions are obtained for guidance track restoring forces, lateral destabilization forces, and lift force degradation as functions of lateral displacement from symmetry. The dependence of lift, drag, and lift-to-drag on track loop parameters is studied and the linear dependence of lift-to-drag on loop time constant confirmed. The contribution to the forces made by successive addition of alternating polarity magnets is calculated and the marked reduction in lift force pulsation noted

  18. Quantification of the lift height for magnetic force microscopy using 3D surface parameters

    International Nuclear Information System (INIS)

    Nenadovic, M.; Strbac, S.; Rakocevic, Z.

    2010-01-01

    In this work, the quantitative conditions for the lift height for imaging of the magnetic field using magnetic force microscopy (MFM) were optimized. A thin cobalt film deposited on a monocrystalline silicon (1 0 0) substrate with a thickness of 55 nm and a thin nickel film deposited on a glass with a thickness of 600 nm were used as samples. The topography of the surface was acquired by tapping mode atomic force microscopy (AFM), while MFM imaging was performed in the lift mode for various lift heights. It was determined that the sensitivity of the measurements was about 10% higher for images obtained at a scan angle of 90 o compared to a scan angle of 0 deg. Therefore, the three-dimensional surface texture parameters, i.e., average roughness, skewness, kurtosis and the bearing ratio, were determined in dependence on the lift height for a scan angle of 90 deg. The results of the analyses of the surface parameters showed that the influence of the substrate and its texture on the magnetic force image could be neglected for lift heights above 40 nm and that the upper lift height limit is 100 nm. It was determined that the optimal values of the lift heights were in the range from 60 to 80 nm, depending on the nature of the sample and on the type of the tip used.

  19. Anomalous dissipation and kinetic-energy distribution in pipes at very high Reynolds numbers.

    Science.gov (United States)

    Chen, Xi; Wei, Bo-Bo; Hussain, Fazle; She, Zhen-Su

    2016-01-01

    A symmetry-based theory is developed for the description of (streamwise) kinetic energy K in turbulent pipes at extremely high Reynolds numbers (Re's). The theory assumes a mesolayer with continual deformation of wall-attached eddies which introduce an anomalous dissipation, breaking the exact balance between production and dissipation. An outer peak of K is predicted above a critical Re of 10^{4}, in good agreement with experimental data. The theory offers an alternative explanation for the recently discovered logarithmic distribution of K. The concept of anomalous dissipation is further supported by a significant modification of the k-ω equation, yielding an accurate prediction of the entire K profile.

  20. Lifted linear phase filter banks and the polyphase-with-advance representation

    Energy Technology Data Exchange (ETDEWEB)

    Brislawn, C. M. (Christopher M.); Wohlberg, B. E. (Brendt E.)

    2004-01-01

    A matrix theory is developed for the noncausal polyphase-with-advance representation that underlies the theory of lifted perfect reconstruction filter banks and wavelet transforms as developed by Sweldens and Daubechies. This theory provides the fundamental lifting methodology employed in the ISO/IEC JPEG-2000 still image coding standard, which the authors helped to develop. Lifting structures for polyphase-with-advance filter banks are depicted in Figure 1. In the analysis bank of Figure 1(a), the first lifting step updates x{sub 0} with a filtered version of x{sub 1} and the second step updates x{sub 1} with a filtered version of x{sub 0}; gain factors 1/K and K normalize the lowpass- and highpass-filtered output subbands. Each of these steps is inverted by the corresponding operations in the synthesis bank shown in Figure 1(b). Lifting steps correspond to upper- or lower-triangular matrices, S{sub i}(z), in a cascade-form decomposition of the polyphase analysis matrix, H{sub a}(z). Lifting structures can also be implemented reversibly (i.e., losslessly in fixed-precision arithmetic) by rounding the lifting updates to integer values. Our treatment of the polyphase-with-advance representation develops an extensive matrix algebra framework that goes far beyond the results of. Specifically, we focus on analyzing and implementing linear phase two-channel filter banks via linear phase lifting cascade schemes. Whole-sample symmetric (WS) and half-sample symmetric (HS) linear phase filter banks are characterized completely in terms of the polyphase-with-advance representation. The theory benefits significantly from a number of new group-theoretic structures arising in the polyphase-with-advance matrix algebra from the lifting factorization of linear phase filter banks.

  1. Software design to calculate and simulate the mechanical response of electromechanical lifts

    Science.gov (United States)

    Herrera, I.; Romero, E.

    2016-05-01

    Lift engineers and lift companies which are involved in the design process of new products or in the research and development of improved components demand a predictive tool of the lift slender system response before testing expensive prototypes. A method for solving the movement of any specified lift system by means of a computer program is presented. The mechanical response of the lift operating in a user defined installation and configuration, for a given excitation and other configuration parameters of real electric motors and its control system, is derived. A mechanical model with 6 degrees of freedom is used. The governing equations are integrated step by step through the Meden-Kutta algorithm in the MATLAB platform. Input data consists on the set point speed for a standard trip and the control parameters of a number of controllers and lift drive machines. The computer program computes and plots very accurately the vertical displacement, velocity, instantaneous acceleration and jerk time histories of the car, counterweight, frame, passengers/loads and lift drive in a standard trip between any two floors of the desired installation. The resulting torque, rope tension and deviation of the velocity plot with respect to the setpoint speed are shown. The software design is implemented in a demo release of the computer program called ElevaCAD. Further on, the program offers the possibility to select the configuration of the lift system and the performance parameters of each component. In addition to the overall system response, detailed information of transients, vibrations of the lift components, ride quality levels, modal analysis and frequency spectrum (FFT) are plotted.

  2. Neurological sequelae of the operation "baby lift" airplane disaster.

    Science.gov (United States)

    Cohen, M; Conners, C K; Brook, I; Feldman, S; Mason, J K; Dugas, M; Collis, L; Copeland, B; Lewis, O; Denhoff, E

    1994-01-01

    The aircraft disaster of the first flight of Operation "Baby Lift", which departed from Saigon, Vietnam, April 4, 1975, was survived by 149 orphaned children on their way to adoptive homes in the West. It had 157 passenger fatalities. The aircraft disaster exposed the surviving children to a complex disaster environment in which subatmospheric decompression, hypoxia, and deceleration were experienced, many children suffered a transient unconsciousness. We examined 135 surviving children between 1978 and 1985. The U.S. resident children were examined in the years 1979 to 1982 at an average age of 8 years and 6 months. They displayed the following symptomatology: attention deficit (> 75%), hyperactivity (> 65%), impulse disorder (> 55%), learning disabilities (> 35%), speech and language pathology (> 70%), and soft neurological signs (> 75%). The European children were examined in the years 1983 to 1985. On arrival at the adoptive home, 2 weeks after the accident they displayed the following symptomatology: muscle hypotonia (26%), seizures (2.5%), and regressed developmental milestones (33%). At the time of the diagnostic evaluations (1983 to 1985) the average age was 11 years and 8 months. They displayed the following symptomatology: attention deficit (59%), hyperactivity (52%), impulse disorder (48%), learning disabilities (43%), soft neurological signs (43%), epilepsy (16%), and speech and language pathology (34%). We conclude that a complex disaster environment can cause brain damage in children without prolonged unconsciousness, and that victims of disasters require a thorough evaluation from a multidisciplinary team.

  3. Computed tomography evaluation of autogenous graft in sinus lift surgery

    International Nuclear Information System (INIS)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro; Alves, Maria Teresa de Seixas

    2001-01-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  4. Fuel-Conservation Guidance System for Powered-Lift Aircraft

    Science.gov (United States)

    Erzberger, Heinz; McLean, John D.

    1981-01-01

    A technique is described for the design of fuel-conservative guidance systems and is applied to a system that was flight tested on board NASA's sugmentor wing jet STOL research aircraft. An important operational feature of the system is its ability to rapidly synthesize fuel-efficient trajectories for a large set of initial aircraft positions, altitudes, and headings. This feature allows the aircraft to be flown efficiently under conditions of changing winds and air traffic control vectors. Rapid synthesis of fuel-efficient trajectories is accomplished in the airborne computer by fast-time trajectory integration using a simplified dynamic performance model of the aircraft. This technique also ensures optimum flap deployment and, for powered-lift STOL aircraft, optimum transition to low-speed flight. Also included in the design is accurate prediction of touchdown time for use in four-dimensional guidance applications. Flight test results have demonstrated that the automatically synthesized trajectories produce significant fuel savings relative to manually flown conventional approaches.

  5. The quest for stall-free dynamic lift

    Science.gov (United States)

    Tung, C.; Mcalister, K. W.; Carr, Lawrence W.; Duque, E.; Zinner, R.

    1992-01-01

    During the past decade, numerous major effects have addressed the question of how to control or alleviate dynamic stall effects on helicopter rotors, but little concrete evidence of any significant reduction of the adverse characteristics of the dynamic stall phenomenon has been demonstrated. Nevertheless, it is important to remember that the control of dynamic stall is an achievable goal. Experiments performed at the US Army Aeroflight-dynamics Directorate more than a decade ago demonstrated that dynamic stall is not an unavoidable penalty of high amplitude motion, and that airfoils can indeed operate dynamically at angles far above the static-stall angle without necessarily forming a stall vortex. These experiments, one of them featuring a slat that was designed from static airfoil considerations, showed that unsteadiness can be a very beneficial factor in the development of high-lift devices for helicopter rotors. The experience drawn from these early experiments is now being focused on a program for the alleviation of dynamic-stall effects on helicopter rotors. The purpose of this effort is to demonstrate that rotor stall can be controlled through an improved understanding of the unsteady effects on airfoil stall and to document the role of specific means that lead to stall alleviation in the three dimensional unsteady environment of helicopter rotors in forward flight. The first concept to be addressed in this program will be a slatted airfoil. A two dimensional unsteady Navier-Stokes code has been modified to compute the flow around a two-element airfoil.

  6. Evaluation of failure of high lift diesel No. 2

    International Nuclear Information System (INIS)

    Loundagin, R.L.

    1976-01-01

    At 6:30 a.m., September 21, 1976, the No. 2 Emergency High Lift Pump Diesel Engine was remotely started from the N Reactor Control Room to provide water for flushing the N Reactor Emergency Cooling System piping. The engine is a General Motors Diesel Engine Model 16-278A, 2 cycle V type, 16 cylinder, developing 1600 horsepower at 750 revolutions per minute. During the flush, water was observed to be overflowing the engine's jacket cooling water expansion tank. The N Reactor Control Room was notified, and the engine was shut down after having run for approximately 15 minutes. Examination of the engine found the No. 5 cylinder liner had ruptured, causing air to be forced into the cooling system. When the engine was stopped, cooling water was admitted to the engine air box and crankcase. All 16 cylinder heads were removed and the cylinder liners were examined using liquid penetrant to detect cracks. A cracked cylinder liner was found in cylinder No. 6, and the cylinder head of cylinder No. 1 was also found to be cracked. An adherent scale and light pitting were observed on the heads of the pistons in cylinders No. 1, 5, and 6, but not in any other cylinders. All damaged parts were replaced, and the engine was reassembled, tested, and declared serviceable

  7. A structural model for composite rotor blades and lifting surfaces

    Science.gov (United States)

    Rehfield, Lawrence W.; Atilgan, Ali R.

    1987-01-01

    Composite material systems are currently candidates for aerospace structures, primarily for the design flexibiity they offer i.e., it is possible to tailor the material and manufacturing approach to the application. Two notable examples are the wing of the Grumman/USAF/DARPA X-29 and rotor blades under development by the U.S.A. Aerostructures Directorate (AVSCOM), Langley Research Center. A working definition of elastic or structural tailoring is the use of structural concept, fiber orientation, ply stacking sequence, and a blend of materials to achieve specific performance goals. In the design process, choices of materials and dimensions are made which produce specific response characteristics which permit the selected goals to be achieved. Common choices for tailoring goals are preventing instabilities or vibration resonances or enhancing damage tolerance. An essential, enabling factor in the design of tailored composite structures is structural modeling that accurately, but simply, characterizes response. The objective of this paper is to improve the single-cell beam model for composite rotor blades or lifting surfaces and to demonstrate its usefullness in applications.

  8. Selective effects of weight and inertia on maximum lifting.

    Science.gov (United States)

    Leontijevic, B; Pazin, N; Kukolj, M; Ugarkovic, D; Jaric, S

    2013-03-01

    A novel loading method (loading ranged from 20% to 80% of 1RM) was applied to explore the selective effects of externally added simulated weight (exerted by stretched rubber bands pulling downward), weight+inertia (external weights added), and inertia (covariation of the weights and the rubber bands pulling upward) on maximum bench press throws. 14 skilled participants revealed a load associated decrease in peak velocity that was the least associated with an increase in weight (42%) and the most associated with weight+inertia (66%). However, the peak lifting force increased markedly with an increase in both weight (151%) and weight+inertia (160%), but not with inertia (13%). As a consequence, the peak power output increased most with weight (59%), weight+inertia revealed a maximum at intermediate loads (23%), while inertia was associated with a gradual decrease in the peak power output (42%). The obtained findings could be of importance for our understanding of mechanical properties of human muscular system when acting against different types of external resistance. Regarding the possible application in standard athletic training and rehabilitation procedures, the results speak in favor of applying extended elastic bands which provide higher movement velocity and muscle power output than the usually applied weights. © Georg Thieme Verlag KG Stuttgart · New York.

  9. The coupled nonlinear dynamics of a lift system

    Energy Technology Data Exchange (ETDEWEB)

    Crespo, Rafael Sánchez, E-mail: rafael.sanchezcrespo@northampton.ac.uk, E-mail: stefan.kaczmarczyk@northampton.ac.uk, E-mail: phil.picton@northampton.ac.uk, E-mail: huijuan.su@northampton.ac.uk; Kaczmarczyk, Stefan, E-mail: rafael.sanchezcrespo@northampton.ac.uk, E-mail: stefan.kaczmarczyk@northampton.ac.uk, E-mail: phil.picton@northampton.ac.uk, E-mail: huijuan.su@northampton.ac.uk; Picton, Phil, E-mail: rafael.sanchezcrespo@northampton.ac.uk, E-mail: stefan.kaczmarczyk@northampton.ac.uk, E-mail: phil.picton@northampton.ac.uk, E-mail: huijuan.su@northampton.ac.uk; Su, Huijuan, E-mail: rafael.sanchezcrespo@northampton.ac.uk, E-mail: stefan.kaczmarczyk@northampton.ac.uk, E-mail: phil.picton@northampton.ac.uk, E-mail: huijuan.su@northampton.ac.uk [The University of Northampton, School of Science and Technology, Avenue Campus, St George' s Avenue, Northampton (United Kingdom)

    2014-12-10

    Coupled lateral and longitudinal vibrations of suspension and compensating ropes in a high-rise lift system are often induced by the building motions due to wind or seismic excitations. When the frequencies of the building become near the natural frequencies of the ropes, large resonance motions of the system may result. This leads to adverse coupled dynamic phenomena involving nonplanar motions of the ropes, impact loads between the ropes and the shaft walls, as well as vertical vibrations of the car, counterweight and compensating sheave. Such an adverse dynamic behaviour of the system endangers the safety of the installation. This paper presents two mathematical models describing the nonlinear responses of a suspension/ compensating rope system coupled with the elevator car / compensating sheave motions. The models accommodate the nonlinear couplings between the lateral and longitudinal modes, with and without longitudinal inertia of the ropes. The partial differential nonlinear equations of motion are derived using Hamilton Principle. Then, the Galerkin method is used to discretise the equations of motion and to develop a nonlinear ordinary differential equation model. Approximate numerical solutions are determined and the behaviour of the system is analysed.

  10. Noise Simulations of the High-Lift Common Research Model

    Science.gov (United States)

    Lockard, David P.; Choudhari, Meelan M.; Vatsa, Veer N.; O'Connell, Matthew D.; Duda, Benjamin; Fares, Ehab

    2017-01-01

    The PowerFLOW(TradeMark) code has been used to perform numerical simulations of the high-lift version of the Common Research Model (HL-CRM) that will be used for experimental testing of airframe noise. Time-averaged surface pressure results from PowerFLOW(TradeMark) are found to be in reasonable agreement with those from steady-state computations using FUN3D. Surface pressure fluctuations are highest around the slat break and nacelle/pylon region, and synthetic array beamforming results also indicate that this region is the dominant noise source on the model. The gap between the slat and pylon on the HL-CRM is not realistic for modern aircraft, and most nacelles include a chine that is absent in the baseline model. To account for those effects, additional simulations were completed with a chine and with the slat extended into the pylon. The case with the chine was nearly identical to the baseline, and the slat extension resulted in higher surface pressure fluctuations but slightly reduced radiated noise. The full-span slat geometry without the nacelle/pylon was also simulated and found to be around 10 dB quieter than the baseline over almost the entire frequency range. The current simulations are still considered preliminary as changes in the radiated acoustics are still being observed with grid refinement, and additional simulations with finer grids are planned.

  11. Comparing the effectiveness of laser vs. conventional endoforehead lifting.

    Science.gov (United States)

    Chang, Cheng-Jen; Yu, De-Yi; Chang, Shu-Ying; Hsiao, Yen-Chang

    2018-04-01

    The objective of this study was to compare the efficacy and safety of laser versus conventional endoforehead lifting. Over a period of 12 years (January 2000-January 2012), a total of 110 patients with hyperactive muscles over the frontal region have been collected for a retrospective study. The SurgiLase 150XJ CO 2 laser system, in conjunction with the flexible FIBERLASE, was used. The endoscope was 4 mm in diameter with an angle of 30°. The primary efficacy measurement was the assessment of the final outcome for using laser vs. conventional methods. Both groups were observed at three weeks, six weeks and six months after surgery. The most common complication in early convalescence (three weeks) was swelling. This was followed by local paraesthesia, ecchymosis, localized hematomas and scar with alopecia. All these problems disappeared completely after the 6-month study period. Based on a chi-square analysis, there were clinically and statistically significant differences favouring the laser endoforehead surgery in the operative time, early and late complications. All patients achieved significant improvement after both laser and conventional endoforehead surgery in the final outcome. However, the early and late complications indicated a greater difference in the laser group.

  12. Failure analysis of axle shaft of a fork lift

    Directory of Open Access Journals (Sweden)

    Souvik Das

    2015-04-01

    Full Text Available An axle shaft of fork lift failed at operation within 296 h of service. The shaft transmits torque from discrepancy to wheel through planetary gear arrangement. A section of fractured axle shaft made of induction-hardened steel was analyzed to determine the root cause of the failure. Optical microscopies as well as field emission gun scanning electron microscopy (FEG-SEM along with energy dispersive spectroscopy (EDS were carried out to characterize the microstructure. Hardness profile throughout the cross-section was evaluated by micro-hardness measurements. Chemical analysis indicated that the shaft was made of 42CrMo4 steel grade as per specification. Microstructural analysis and micro-hardness profile revealed that the shaft was improperly heat treated resulting in a brittle case, where crack was found to initiate from the case in a brittle mode in contrast to ductile mode within the core. This behaviour was related to differences in microstructure, which was observed to be martensitic within the case with a micro-hardness equivalent to 735 HV, and a mixture of non-homogeneous structure of pearlite and ferrite within the core with a hardness of 210 HV. The analysis suggests that the fracture initiated from the martensitic case as brittle mode due to improper heat treatment process (high hardness. Moreover the inclusions along the hot working direction i.e. in the longitudinal axis made the component more susceptible to failure.

  13. Investigation of particle lift off in a turbulent boundary layer

    Science.gov (United States)

    Barros, Diogo; Tee, Yi Hui; Morse, Nicholas; Hiltbrand, Ben; Longmire, Ellen

    2017-11-01

    Entrainment and suspension of particles within turbulent flows occur widely in environmental and industrial processes. Three-dimensional particle tracking experiments are thus conducted in a water channel to understand the interaction of finite-size particles with a turbulent boundary layer. A neutrally buoyant sphere made of wax and iron oxide is first held in place on the bounding surface by a magnet before being released and tracked. The sphere is marked with dots to monitor rotation as well as translation. By setting up two pairs of cameras in a stereoscopic configuration, the trajectories of the sphere are reconstructed and tracked over a distance of 4 to 6 δ. Sphere diameters ranging from 40 to 130 wall units, initial particle Reynolds numbers of 600 to 2000 and friction Reynolds numbers of 500 to 1800 are considered. For this parameter set, the particle typically lifts off from the wall after release before falling back toward the wall. Aspects of both particle rotation and translation will be discussed. Supported by NSF (CBET-1510154).

  14. Advanced wind turbine with lift-destroying aileron for shutdown

    Science.gov (United States)

    Coleman, Clint; Juengst, Theresa M.; Zuteck, Michael D.

    1996-06-18

    An advanced aileron configuration for wind turbine rotors featuring an aileron with a bottom surface that slopes upwardly at an angle toward the nose region of the aileron. The aileron rotates about a center of rotation which is located within the envelope of the aileron, but does not protrude substantially into the air flowing past the aileron while the aileron is deflected to angles within a control range of angles. This allows for strong positive control of the rotation of the rotor. When the aileron is rotated to angles within a shutdown range of deflection angles, lift-destroying, turbulence-producing cross-flow of air through a flow gap, and turbulence created by the aileron, create sufficient drag to stop rotation of the rotor assembly. The profile of the aileron further allows the center of rotation to be located within the envelope of the aileron, at or near the centers of pressure and mass of the aileron. The location of the center of rotation optimizes aerodynamically and gyroscopically induced hinge moments and provides a fail safe configuration.

  15. Cooperative control system of the floating cranes for the dual lifting

    OpenAIRE

    Mihee Nam; Jinbeom Kim; Jaechang Lee; Daekyung Kim; Donghyuk Lee; Jangmyung Lee

    2018-01-01

    This paper proposes a dual lifting and its cooperative control system with two different kinds of floating cranes. The Mega-erection and Giga-erection in the ship building are used to handle heavier and wider blocks and modules as ships and off-shore platforms are enlarged. However, there is no equipment to handle such Tera-blocks. In order to overcome the limit on performance of existing floating cranes, the dual lifting is proposed in this research. In the dual lifting, two floating cranes ...

  16. Flow Control Research at NASA Langley in Support of High-Lift Augmentation

    Science.gov (United States)

    Sellers, William L., III; Jones, Gregory S.; Moore, Mark D.

    2002-01-01

    The paper describes the efforts at NASA Langley to apply active and passive flow control techniques for improved high-lift systems, and advanced vehicle concepts utilizing powered high-lift techniques. The development of simplified high-lift systems utilizing active flow control is shown to provide significant weight and drag reduction benefits based on system studies. Active flow control that focuses on separation, and the development of advanced circulation control wings (CCW) utilizing unsteady excitation techniques will be discussed. The advanced CCW airfoils can provide multifunctional controls throughout the flight envelope. Computational and experimental data are shown to illustrate the benefits and issues with implementation of the technology.

  17. Lift Production on Flapping and Rotary Wings at Low Reynolds Numbers

    Science.gov (United States)

    2016-02-26

    AFRL-AFOSR-VA-TR-2016-0098 Flapping and Rotary Wing Lift at Low Reynolds Number Anya Jones MARYLAND UNIV COLLEGE PARK Final Report 02/26/2016...Lift Production on Flapping and Rotary Wings at Low Reynolds Numbers (YIP) 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-12-1-0251 5c. PROGRAM...necessary if the abstract is to be limited. Standard Form 298 Back (Rev. 8/98) Lift Production on Flapping and Rotary Wings at Low Reynolds Numbers

  18. STRUCTURAL AND GEOMETRICAL ANALYSIS OF THE LIFTING MANIPULATORS FOR A GREEN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Ioana POPESCU

    2015-12-01

    Full Text Available The lifting and getting off the bins, to and from the body of special waste trucks, by some planar linkage – manipulators are studied. These lifting manipulators are equipped with gripper systems in order to load and unload the bins. Several kinematical schemas of type mono– and bi-mobile manipulators are analyzed, these being driven by one or two linear actuators. The kinematical geometry of these planar manipulators by means of scale drawing of the kinematical schema is displayed. Two solutions for a better efficiency and a green environment have been proposed. Finally, a modeling and simulation case of the lifting manipulator is presented.

  19. Numerical Investigation of Effect of Parameters on Hovering Efficiency of an Annular Lift Fan Aircraft

    OpenAIRE

    Yun Jiang; Bo Zhang

    2016-01-01

    The effects of various parameters on the hovering performance of an annular lift fan aircraft are investigated by using numerical scheme. The pitch angle, thickness, aspect ratio (chord length), number of blades, and radius of duct inlet lip are explored to optimize the figure of merit. The annular lift fan is also compared with a conventional circular lift fan of the same features with the same disc loading and similar geometry. The simulation results show that the pitch angle of 27°, the th...

  20. An Extensional Characterization of Lambda-Lifting and Lambda-Dropping

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1999-01-01

    Lambda-lifting and lambda-dropping respectively transform a block-structured functional program into recursive equations and vice versa. Lambda-lifting was developed in the early 80’s, whereas lambda-dropping is more recent. Both are split into an analysis and a transformation. Published work......, however, has only concentrated on the analysis parts. We focus here on the transformation parts and more precisely on their correctness, which appears never to have been proven. To this end, we define extensional versions of lambda-lifting and lambda-dropping and establish their correctness with respect...

  1. KAPPEL Propeller. Development of a Marine Propeller with Non-planar Lifting Surfaces

    DEFF Research Database (Denmark)

    Kappel, J.; Andersen, Poul

    2002-01-01

    The principle of non-planar lifting surfaces is applied to the design of modern aircraft wings to obtain better lift to drag ratios. Whereas a pronounced fin or "winglet" at the wingtip has been developed for aircraft, the application of the non-planar principle to marine propellers, dealt...... with in this paper, has led to the KAPPEL propeller with blades curved towards the suction side integrating the fin or winglet into the propeller blade. The combined theoretical, experimental and practical approach to develop and design marine propellers with non-planar lifting surfaces has resulted in propellers...

  2. An Extensional Characterization of Lambda-Lifting and Lambda-Dropping

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Lambda-lifting and lambda-dropping respectively transform a block-structured functional program into recursive equations and vice versa. Lambda-lifting was developed in the early 80’s, whereas lambda-dropping is more recent. Both are split into an analysis and a transformation. Published work......, however, has only concentrated on the analysis parts. We focus here on the transformation parts and more precisely on their correctness, which appears never to have been proven. To this end, we define extensional versions of lambda-lifting and lambda-dropping and establish their correctness with respect...

  3. A Lift-Off-Tolerant Magnetic Flux Leakage Testing Method for Drill Pipes at Wellhead

    OpenAIRE

    Wu, Jianbo; Fang, Hui; Li, Long; Wang, Jie; Huang, Xiaoming; Kang, Yihua; Sun, Yanhua; Tang, Chaoqing

    2017-01-01

    To meet the great needs for MFL (magnetic flux leakage) inspection of drill pipes at wellheads, a lift-off-tolerant MFL testing method is proposed and investigated in this paper. Firstly, a Helmholtz coil magnetization method and the whole MFL testing scheme are proposed. Then, based on the magnetic field focusing effect of ferrite cores, a lift-off-tolerant MFL sensor is developed and tested. It shows high sensitivity at a lift-off distance of 5.0 mm. Further, the follow-up high repeatabilit...

  4. Enhancing multi-step quantum state tomography by PhaseLift

    Science.gov (United States)

    Lu, Yiping; Zhao, Qing

    2017-09-01

    Multi-photon system has been studied by many groups, however the biggest challenge faced is the number of copies of an unknown state are limited and far from detecting quantum entanglement. The difficulty to prepare copies of the state is even more serious for the quantum state tomography. One possible way to solve this problem is to use adaptive quantum state tomography, which means to get a preliminary density matrix in the first step and revise it in the second step. In order to improve the performance of adaptive quantum state tomography, we develop a new distribution scheme of samples and extend it to three steps, that is to correct it once again based on the density matrix obtained in the traditional adaptive quantum state tomography. Our numerical results show that the mean square error of the reconstructed density matrix by our new method is improved to the level from 10-4 to 10-9 for several tested states. In addition, PhaseLift is also applied to reduce the required storage space of measurement operator.

  5. Effects of Variable Valve Lift on In-Cylinder Air Motion

    Directory of Open Access Journals (Sweden)

    Tianyou Wang

    2015-12-01

    Full Text Available An investigation into in-cylinder swirl and tumble flow characteristics with reduced maximum valve lifts (MVL is presented. The experimental work was conducted in the modified four-valve optical spark-ignition (SI test engine with three different MVL. Particle image velocimetry (PIV was employed for measuring in-cylinder air motion and measurement results were analyzed for examining flow field, swirl and tumble ratio variation and fluctuating kinetic energy distribution. Results of ensemble-averaged flow fields show that reduced MVL could produce strong swirl flow velocity, then resulted in very regular swirl motion in the late stage of the intake process. The strong swirl flow can maintain very well until the late compression stage. The reduction of MVL can also increase both high-frequency and low-frequency swirl flow fluctuating kinetic energy remarkably. Regarding tumble flow, results demonstrate that lower MVLs result in more horizontal intake flow velocity vectors which can be easily detected under the valve seat area. Although the result of lower MVLs show a higher tumble ratio when the piston is close to the bottom dead centre (BDC, higher MVLs substantially produce higher tumble ratios which can be confirmed when most cylinder area lies in the measuring range.

  6. Inspection and repair of storage tank bottoms and foundations using airbag lifting

    International Nuclear Information System (INIS)

    Wildin, I.P.; Adams, N.J.

    1992-01-01

    This paper reports that within the past five years the environmental impact on the operation of petro-chemical product storage tanks, constructed to standards such as API 650, has taken on critical implications for refineries and distribution centers. Pollution of the supporting foundation and possible widespread effects on ground water has resulted in moves to require the installation of double integrity bottoms. That is not to say, necessarily, a tank with two steel bottoms, but alternative means of reducing the failure probability to an acceptable public or statutory level. Clearly increased inspection of the tank bottom has merit and visual examination of the bottom from inside the tank can be supplemented by ultrasonic methods, acoustic leak detection and magnetic flux scanning. Tank lifting now offers a very cost effective method for underfloor inspection, combined with the opportunity to undertake repairs to the bottom and underside painting, together with improvements and repairs to the Bitsand surface of the tank pad. if necessary, an impervious membrane can also be installed with a leak detection trough formed around the tank edge

  7. Lift the quilt in case of atrial fibrillation and disc prolapse.

    Science.gov (United States)

    Bastovansky, Adam; Ziegler, Kathrin; Stöllberger, Claudia; Finsterer, Josef

    2012-01-01

    Peripheral embolism to the lower extremities may mimic disc prolapse with severe consequences. A 71-year-old male with a history of chronic alcoholism developed low back pain radiating to both lower extremities in a nonradicular distribution and bilateral dysesthesias of the distal lower legs after lifting a heavy weight. Given that magnetic resonance imaging (MRI) of the lumbar spine showed disc herniation in L3/4 and L4/5, he was scheduled for laminectomy but was unable to undergo surgery due to thrombocytopenia. After transfer to another hospital, persistence of symptoms and signs, absent pulses on the distal lower legs, and rhabdomyolysis with temporary renal insufficiency, peripheral embolism with compartment syndrome was suspected. Magnetic resonance angiography revealed occlusion of the right superficial femoral artery and long high-grade stenosis of the left superficial and profound femoral arteries and distal arteries. He successfully underwent embolectomy and fasciotomy. If lumbar pain is not radicular, peripheral pulses are minimally palpable, and distal limbs are cold and show livid decolorization, peripheral embolism is much more likely than disc herniation, particularly if the patient's history is positive for atrial fibrillation. MRI of the lumbar spine must be interpreted in conjunction with clinical presentation.

  8. Lift the quilt in case of atrial fibrillation and disc prolapse

    Directory of Open Access Journals (Sweden)

    Bastovansky A

    2012-06-01

    Full Text Available Adam Bastovansky,1 Kathrin Ziegler,2 Claudia Stöllberger,2 Josef Finsterer31Department of Radiology, 2Medical Department, Krankenanstalt Rudolfstiftung, Vienna, Austria; 3Danube University Krems, Krems, AustriaBackground: Peripheral embolism to the lower extremities may mimic disc prolapse with severe consequences.Case report:  A 71-year-old male with a history of chronic alcoholism developed low back pain radiating to both lower extremities in a nonradicular distribution and bilateral dysesthesias of the distal lower legs after lifting a heavy weight. Given that magnetic resonance imaging (MRI of the lumbar spine showed disc herniation in L3/4 and L4/5, he was scheduled for laminectomy but was unable to undergo surgery due to thrombocytopenia. After transfer to another hospital, persistence of symptoms and signs, absent pulses on the distal lower legs, and rhabdomyolysis with temporary renal insufficiency, peripheral embolism with compartment syndrome was suspected. Magnetic resonance angiography revealed occlusion of the right superficial femoral artery and long high-grade stenosis of the left superficial and profound femoral arteries and distal arteries. He successfully underwent embolectomy and fasciotomy.Conclusions: If lumbar pain is not radicular, peripheral pulses are minimally palpable, and distal limbs are cold and show livid decolorization, peripheral embolism is much more likely than disc herniation, particularly if the patient's history is positive for atrial fibrillation. MRI of the lumbar spine must be interpreted in conjunction with clinical presentation.Keywords: embolism, compartment syndrome, neurosurgery, embolectomy, fasciotomy, rhabdomyolysis

  9. Autoignited laminar lifted flames of methane, ethylene, ethane, and n-butane jets in coflow air with elevated temperature

    KAUST Repository

    Choi, Byungchul

    2010-12-01

    The autoignition characteristics of laminar lifted flames of methane, ethylene, ethane, and n-butane fuels have been investigated experimentally in coflow air with elevated temperature over 800. K. The lifted flames were categorized into three regimes depending on the initial temperature and fuel mole fraction: (1) non-autoignited lifted flame, (2) autoignited lifted flame with tribrachial (or triple) edge, and (3) autoignited lifted flame with mild combustion. For the non-autoignited lifted flames at relatively low temperature, the existence of lifted flame depended on the Schmidt number of fuel, such that only the fuels with Sc > 1 exhibited stationary lifted flames. The balance mechanism between the propagation speed of tribrachial flame and local flow velocity stabilized the lifted flames. At relatively high initial temperatures, either autoignited lifted flames having tribrachial edge or autoignited lifted flames with mild combustion existed regardless of the Schmidt number of fuel. The adiabatic ignition delay time played a crucial role for the stabilization of autoignited flames. Especially, heat loss during the ignition process should be accounted for, such that the characteristic convection time, defined by the autoignition height divided by jet velocity was correlated well with the square of the adiabatic ignition delay time for the critical autoignition conditions. The liftoff height was also correlated well with the square of the adiabatic ignition delay time. © 2010 The Combustion Institute.

  10. Two years' outcome of thread lifting with absorbable barbed PDO threads: Innovative score for objective and subjective assessment.

    Science.gov (United States)

    Ali, Yasser Helmy

    2018-02-01

    Thread-lifting rejuvenation procedures have evolved again, with the development of absorbable threads. Although they have gained popularity among plastic surgeons and dermatologists, very few articles have been written in literature about absorbable threads. This study aims to evaluate two years' outcome of thread lifting using absorbable barbed threads for facial rejuvenation. Prospective comparative stud both objectively and subjectively and follow-up assessment for 24 months. Thread lifting for face rejuvenation has significant long-lasting effects that include skin lifting from 3-10 mm and high degree of patients' satisfaction with less incidence rate of complications, about 4.8%. Augmented results are obtained when thread lifting is combined with other lifting and rejuvenation modalities. Significant facial rejuvenation is achieved by thread lifting and highly augmented results are observed when they are combined with Botox, fillers, and/or platelet rich plasma (PRP) rejuvenations.

  11. Lift-based up-ender and methods using same to manipulate a shipping container containing unirradiated nuclear fuel

    Science.gov (United States)

    Nilles, Michael J.

    2017-08-01

    A shipping container containing an unirradiated nuclear fuel assembly is lifted off the ground by operating a crane to raise a lifting tool comprising a winch. The lifting tool is connected with the shipping container by a rigging line connecting with the shipping container at a lifting point located on the shipping container between the top and bottom of the shipping container, and by winch cabling connecting with the shipping container at the top of the shipping container. The shipping container is reoriented by operating the winch to adjust the length of the winch cabling so as to rotate the shipping container about the lifting point. Shortening the winch cabling rotates the shipping container about the lifting point from a horizontal orientation to a vertical orientation, while lengthening the winch cabling rotates the shipping container about the lifting point from the vertical orientation to the horizontal orientation.

  12. Lift 11 paneb arhitektid ja kunstnikud linna arendama / Oliver Õunmaa

    Index Scriptorium Estoniae

    Õunmaa, Oliver

    2011-01-01

    Kultuuripealinna programmi raames maist septembrini Tallinna avalikus ruumis toimuvast linnainstallatsioonide festivalist "Lift11". Kuraatorid Margit Aule, Margit Argus, Maarin Mürk, Ingrid Ruudi. Ideekonkursile esitatud 129 teosest valiti teostamiseks 17 installatsiooni. Tutvustab Margit Aule

  13. Revised design calculations of lift systems; Elevator no setsubi keikaku ni okeru kotsu keisan

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, T.; Komaya, K. [Mitsubishi Electric Corp., Tokyo (Japan)

    1998-07-01

    For sufficient transportation capacity and passengers comfort and convenience, it is very important to design the suitable lift systems (e.g., the appropriate number of cages, velocity, capacity etc.) using a model which describes real elevator movements. The procedure used in conventional design calculations for office buildings is to determine the transportation capacity for the up-peak traffic situation using a simple passengers arrival model. This paper presents a new design calculations using balanced traffic model, which can deal with the elevator movements considering passengers arrival rate. As some performance indexes to evaluate the quality of service can be calculated by using this model, lift system designers can determine the appropriate lift facilities as to satisfy their goals. The validity of the proposed model is also shown by comparing with the measured data in real lift systems. 6 refs., 9 figs., 2 tabs.

  14. A crude solution: should the moratorium on offshore oil and gas development in BC be lifted

    International Nuclear Information System (INIS)

    Parfitt, B.; Venton, M.; Bartoszewski, D.

    1999-04-01

    A discussion on the pros and cons of lifting the moratorium on offshore oil development is presented. The Federal Fisheries Minister is not convinced that technological advances have reached a point where the moratorium can be lifted and guarantee that major accidents would not occur. The Fisheries Act states that any degradation of fish habitat is illegal. Coastal communities are also opposed to lifting the moratorium, yet it is widely rumored that the provincial government is planning to set up an environmental review to investigate the possibility of developing the offshore resource. The Sierra Legal Defence Fund supports the federal government's position that lifting the moratorium on offshore oil development would seriously jeopardize many sectors of the coastal economy, and urges both levels of government to work together and instead of engaging in such potentially hazardous and costly endeavour, encourage growth and development in the domestic renewable energy sector. 37 refs., figs

  15. Autoignited laminar lifted flames of methane/hydrogen mixtures in heated coflow air

    KAUST Repository

    Choi, Byungchul

    2012-04-01

    Autoignited lifted flame behavior in laminar jets of methane/hydrogen mixture fuels has been investigated experimentally in heated coflow air. Three regimes of autoignited lifted flames were identified depending on initial temperature and hydrogen to methane ratio. At relatively high initial temperature, addition of a small amount of hydrogen to methane improved ignition appreciably such that the liftoff height decreased significantly. In this hydrogen-assisted autoignition regime, the liftoff height increased with jet velocity, and the characteristic flow time - defined as the ratio of liftoff height to jet velocity - correlated well with the square of the adiabatic ignition delay time. At lower temperature, the autoignited lifted flame demonstrated a unique feature in that the liftoff height decreased with increasing jet velocity. Such behavior has never been observed in lifted laminar and turbulent jet flames. A transition regime existed between these two regimes at intermediate temperature. © 2011 The Combustion Institute.

  16. Power consumption of lifts and potential for energy savings; Elektrizitaetsverbrauch und Einspar-Potenziale bei Aufzuegen

    Energy Technology Data Exchange (ETDEWEB)

    Nipkow, J.

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) reviews the results of a study made on the electricity consumption of lifts, which estimates that around 0.5% of Swiss power consumption is caused by lift installations. The results of measurements made on 33 various lift installations and their power consumption are presented. The SIA 380/4 model used to determine energy consumption on the basis of the number of movements is described. Stand-by and lighting consumption is examined, which, according to the authors' conclusions, offer considerable room for improvement, especially for lifts in residential buildings. A further significant potential for improvement is also noted which can be achieved when renewing older systems. The avoidance of inefficient concepts by the use of guidelines for architects, planners and customers is recommended.

  17. Analysis of multicriteria models application for selection of an optimal artificial lift method in oil production

    Directory of Open Access Journals (Sweden)

    Crnogorac Miroslav P.

    2016-01-01

    Full Text Available In the world today for the exploitation of oil reservoirs by artificial lift methods are applied different types of deep pumps (piston, centrifugal, screw, hydraulic, water jet pumps and gas lift (continuous, intermittent and plunger. Maximum values of oil production achieved by these exploitation methods are significantly different. In order to select the optimal exploitation method of oil well, the multicriteria analysis models are used. In this paper is presented an analysis of the multicriteria model's application known as VIKOR, TOPSIS, ELECTRE, AHP and PROMETHEE for selection of optimal exploitation method for typical oil well at Serbian exploration area. Ranking results of applicability of the deep piston pumps, hydraulic pumps, screw pumps, gas lift method and electric submersible centrifugal pumps, indicated that in the all above multicriteria models except in PROMETHEE, the optimal method of exploitation are deep piston pumps and gas lift.

  18. Numerical Investigation of Effect of Parameters on Hovering Efficiency of an Annular Lift Fan Aircraft

    Directory of Open Access Journals (Sweden)

    Yun Jiang

    2016-10-01

    Full Text Available The effects of various parameters on the hovering performance of an annular lift fan aircraft are investigated by using numerical scheme. The pitch angle, thickness, aspect ratio (chord length, number of blades, and radius of duct inlet lip are explored to optimize the figure of merit. The annular lift fan is also compared with a conventional circular lift fan of the same features with the same disc loading and similar geometry. The simulation results show that the pitch angle of 27°, the thickness of 4% chord length, the aspect ratio of 3.5~4.0, 32 blades, and the radius of inlet lip of 4.7% generate the maximum figure of merit of 0.733. The optimized configuration can be used for further studies of the annular lift fan aircraft.

  19. Comparison of Bottomless Lift Nets and Breder Traps for Sampling Salt-Marsh Nekton

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data set contains: the length of mummichogs (Fundulus heteroclitus) caught on lift nets and Breder traps from May to September 2002; the sizes of green crabs caught...

  20. Blade Section Lift Coefficients for Propellers at Extreme Off-Design Conditions

    National Research Council Canada - National Science Library

    Shen, Young

    1997-01-01

    The Propeller Force Module (PFM) code developed by Analytical Methods Inc. (AMI) for calculating propeller side forces during maneuvering simulation studies requires inputs of propeller blade sectional lift, drag, and moment data...

  1. Behavior in exploitation of gas-lift installations with differential valves. Pt. 2

    Energy Technology Data Exchange (ETDEWEB)

    Bodea, I; Truica, V

    1969-07-01

    In this second installment, charts of casing and tubing pressure are shown to illustrate how they can be used as diagnostic tools, both for continuous and intermittent gas-lift installations. The desirable conditions for continuous gas lift are constant casing and tubing pressures; for intermittent gas lift, cycles of equal length and intensity. After discussion of the possible flow regimes in the production tubing, it is shown that pressure gradient and temperature measurements can also be used as diagnostic tools. The basic rules for designing a continuous flow gas-lift installation by multipoint injection are given. Application of these principles in several wells has resulted in an increase in the oil production rate, a decrease in the gas requirement, and a reduction in the frequency of well pulling jobs. A well-designed installation can be expected to function trouble- free for 2 to 4 yr.

  2. Powering and Motion Predictions of High Speed Sea Lift (HSSL) Ships

    National Research Council Canada - National Science Library

    Gorski, Joseph; Miller, Ronald; Carrica, Pablo; Kandasamy, Mani; Stern, Fred

    2007-01-01

    High Speed Sea Lift (HSSL) is an important area of in terest for the US Navy. Computational tools are needed to predict the hydrodynamics of these configurations for their proper design and analysis in many areas including...

  3. Different levels of undermining in face lift - Experience of 141 consecutive cases

    Directory of Open Access Journals (Sweden)

    Panettiere Pietro

    2004-01-01

    Full Text Available CONTEXT: The most revolutionary concept in rhytidectomy is the role of Sub Muscular Aponeurotic System (SMAS, even if many alternative approaches have been proposed. The main aim of face lift is to bring back the time, preventing the "lifted-face" appearance. SETTINGS AND DESIGN: The authors present their personal experience with different levels of undermining, i.e. subperiosteal forehead lift, subcutaneous midface lift with SMAS plication and platysmal suspension, and discuss the anatomical and biomechanical elements of rhytidectomy. RESULTS: Optimal aesthetic results were achieved by repositioning the neck, face and forehead tissues in a global and harmonious fashion, without distorting face characteristics and disguising surgery trails as much as possible. CONCLUSIONS: Different levels of undermining can give good and stable aesthetic results minimizing the risks and preventing face distortion.

  4. Lifting forces acting on a cylindrical magnet above a superconducting plane

    International Nuclear Information System (INIS)

    Yang, Z.J.; Johansen, T.H.; Bratsberg, H.; Bhatnagar, A.; Skjeltorp, A.T.

    1992-01-01

    Based on the London theory, we have calculated and measured the lifting force acting on a cylindrical magnet placed above a superconductor. Comparison between the theoretical expectation and experimental data shows a good agreement. (orig.)

  5. Lumbar muscle activity during common lifts: a preliminary study using magnetic resonance imaging.

    Science.gov (United States)

    Mayer, John M; Graves, James E; Manini, Todd M; Nuzzo, James L; Ploutz-Snyder, Lori L

    2013-04-01

    The purpose of this preliminary study was to assess lumbar multifidus, erector spinae, and quadratus lumborum muscle activity during lifts as measured by changes in transverse relaxation time (T2) from magnetic resonance imaging (MRI). Thirteen healthy adults performed dynamic squat, stoop, and asymmetric stoop lifts at a standard load, with each lift followed by MRI. Increase in T2 for the multifidus and erector spinae was greater for the stoop than squat. No difference in T2 increase was noted between the multifidus and erector spinae for the squat or stoop. Increase in T2 for the contralateral multifidus was less for the asymmetric stoop than stoop. Future research using MRI and other biomechanical techniques is needed to fully characterize lumbar muscle activity during lifts for various populations, settings, postures, and loads.

  6. Temple and Postauricular Dissection in Face and Neck Lift Surgery

    Directory of Open Access Journals (Sweden)

    Joo Heon Lee

    2017-07-01

    Full Text Available Periauricular paresthesia may afflict patients for a significant amount of time after facelift surgery. When performing face and neck lift surgery, temple and posterior auricular flap dissection is undertaken directly over the auriculotemporal, great auricular, and lesser occipital nerve territory, leading to potential damage to the nerve. The auriculotemporal nerve remains under the thin outer superficial fascia just below the subfollicular level in the prehelical area. To prevent damage to the auriculotemporal nerve and to protect the temporal hair follicle, the dissection plane should be kept just above the thin fascia covering the auriculotemporal nerve. Around the McKinney point, the adipose tissue covering the deep fascia is apt to be elevated from the deep fascia due to its denser fascial relationship with the skin, which leaves the great auricular nerve open to exposure. In order to prevent damage to the posterior branches of the great auricular nerve, the skin flap at the posterior auricular sulcus should be elevated above the auricularis posterior muscle. Fixating the superficial muscular aponeurotic system flap deeper and higher to the tympano-parotid fascia is recommended in order to avoid compromising the lobular branch of the great auricular nerve. The lesser occipital nerve (C2, C3 travels superficially at a proximal and variable level that makes it vulnerable to compromise in the mastoid dissection. Leaving the adipose tissue at the level of the deep fascia puts the branches of the great auricular nerve and lesser occipital nerve at less risk, and has been confirmed not to compromise either tissue perfusion or hair follicles.

  7. Titan Lifting Entry & Atmospheric Flight (T-LEAF) Science Mission

    Science.gov (United States)

    Lee, G.; Sen, B.; Ross, F.; Sokol, D.

    2016-12-01

    Northrop Grumman has been developing the Titan Lifting Entry & Atmospheric Flight (T-LEAF) sky rover to roam the lower atmosphere and observe at close quarters the lakes and plains of Saturn's ocean moon, Titan. T-LEAF also supports surface exploration and science by providing precision delivery of in-situ instruments to the surface of Titan. T-LEAF is a highly maneuverable sky rover and its aerodynamic shape (i.e., a flying wing) does not restrict it to following prevailing wind patterns on Titan, but allows mission operators to chart its course. This freedom of mobility allows T-LEAF to follow the shorelines of Titan's methane lakes, for example, or to target very specific surface locations. We will present a straw man concept of T-LEAF, including size, mass, power, on-board science payloads and measurement, and surface science dropsonde deployment CONOPS. We will discuss the various science instruments and their vehicle level impacts, such as meteorological and electric field sensors, acoustic sensors for measuring shallow depths, multi-spectral imagers, high definition cameras and surface science dropsondes. The stability of T-LEAF and its long residence time on Titan will provide for time to perform a large aerial survey of select prime surface targets deployment of dropsondes at selected locations surface measurements that are coordinated with on-board remote measurements communication relay capabilities to orbiter (or Earth). In this context, we will specifically focus upon key factors impacting the design and performance of T-LEAF science: science payload accommodation, constraints and opportunities characteristics of flight, payload deployment and measurement CONOPS in the Titan atmosphere. This presentation will show how these factors provide constraints as well as enable opportunities for novel long duration scientific studies of Titan's surface.

  8. Cognitive-motor interference while grasping, lifting and holding objects.

    Directory of Open Access Journals (Sweden)

    Erwan Guillery

    Full Text Available In daily life, object manipulation is usually performed concurrently to the execution of cognitive tasks. The aim of the present study was to determine which aspects of precision grip require cognitive resources using a motor-cognitive dual-task paradigm. Eighteen healthy participants took part in the experiment, which comprised two conditions. In the first condition, participants performed a motor task without any concomitant cognitive task. They were instructed to grip, lift and hold an apparatus incorporating strain gauges allowing a continuous measurement of the force perpendicular to each contact surface (grip force, GF as well as the total tangential force applied on the object (load force, LF. In the second condition, participants performed the same motor task while concurrently performing a cognitive task consisting in a complex visual search combined with counting. In the dual-task condition, we found a significant increase in the duration of the preload phase (time between initial contact of the fingers with the apparatus and onset of the load force, as well as a significant increase of the grip force during the holding phase, indicating that the cognitive task interfered with the initial force scaling performed during the preload phase and the fine-tuning of grip force during the hold phase. These findings indicate that these aspects of precision grip require cognitive resources. In contrast, other aspects of the precision grip, such as the temporal coupling between grip and load forces, were not affected by the cognitive task, suggesting that they reflect more automatic processes. Taken together, our results suggest that assessing the dynamic and temporal parameters of precision grip in the context of a concurrent cognitive task may constitute a more ecological and better-suited tool to characterize motor dysfunction in patients.

  9. An introduction of gauge field by the Lie-isotopic lifting of the Hilbert space

    International Nuclear Information System (INIS)

    Nishioka, M.

    1984-01-01

    It is introduced the gauge field by the Lie-isotopic lifting of the Hilbert space. Our method is different from other's in that the commutator between the isotropic element and the generators of the Lie algebra does not vanish in our case, but vanishes in other cases. Our method uses the Lie-isotopic lifting of the Hilbert space, but others do not use it

  10. Turbulence induced lift experienced by large particles in a turbulent flow

    International Nuclear Information System (INIS)

    Zimmermann, Robert; Gasteuil, Yoann; Volk, Romain; Pumir, Alain; Pinton, Jean-François; Bourgoin, Mickaël

    2011-01-01

    The translation and rotation of a large, neutrally buoyant, particle, freely advected by a turbulent flow is determined experimentally. We observe that, both, the orientation the angular velocity with respect to the trajectory and the translational acceleration conditioned on the spinning velocity provides evidence of a lift force, F lift ∝ ω × ν rel , acting on the particle. New results of the dynamics of the coupling between the particle's rotation and its translation are presented.

  11. Scaling of Lift Degradation Due to Anti-Icing Fluids Based Upon the Aerodynamic Acceptance Test

    Science.gov (United States)

    Broeren, Andy P.; Riley, James T.

    2012-01-01

    In recent years, the FAA has worked with Transport Canada, National Research Council Canada (NRC) and APS Aviation, Inc. to develop allowance times for aircraft operations in ice-pellet precipitation. These allowance times are critical to ensure safety and efficient operation of commercial and cargo flights. Wind-tunnel testing with uncontaminated anti-icing fluids and fluids contaminated with simulated ice pellets had been carried out at the NRC Propulsion and Icing Wind Tunnel (PIWT) to better understand the flowoff characteristics and resulting aerodynamic effects. The percent lift loss on the thin, high-performance wing model tested in the PIWT was determined at 8 angle of attack and used as one of the evaluation criteria in determining the allowance times. Because it was unclear as to how performance degradations measured on this model were relevant to an actual airplane configuration, some means of interpreting the wing model lift loss was deemed necessary. This paper describes how the lift loss was related to the loss in maximum lift of a Boeing 737-200ADV airplane through the Aerodynamic Acceptance Test (AAT) performed for fluids qualification. A loss in maximum lift coefficient of 5.24 percent on the B737-200ADV airplane (which was adopted as the threshold in the AAT) corresponds to a lift loss of 7.3 percent on the PIWT model at 8 angle of attack. There is significant scatter in the data used to develop the correlation related to varying effects of the anti-icing fluids that were tested and other factors. A statistical analysis indicated the upper limit of lift loss on the PIWT model was 9.2 percent. Therefore, for cases resulting in PIWT model lift loss from 7.3 to 9.2 percent, extra scrutiny of the visual observations is required in evaluating fluid performance with contamination.

  12. Penggunaan Photo Dan Infra Red Pada Perancangan Lift Untuk 3 Lantai Berbasis Mikrokontroler

    OpenAIRE

    Aji Winata Utama

    2009-01-01

    Pada gedung gedung besar yang memiliki lebih dari satu lantai diperlukan tangga yang dapat menghubungkan satu lantai ke lantai lainnya. Namun dengan menggunakan tangga masih kurang efisien. Karena itu dibutuhkan sebuah lift yang dapat menghubungkan sseluruh lantai yang terdapat dalam gedung tersebut. Untuk mengendalikan sebuah lift diperlukan sebuah motor dan pengontrol system. Dalam penelitian ini motor yang digunakan adalah motor stepper dan sebagai pengontrol system digun...

  13. Analysis of the flexible receiver lifting yoke and blast shield assembly. Tank 241SY101

    International Nuclear Information System (INIS)

    Huang, F.H.

    1995-01-01

    The analysis of the lifting yoke and blast shield assembly considers the bending stress, weld strength, and resistance of the lug hole to tear out. The bending stress of the lifting lugs is evaluated to ensure that they meet the requirements of the American Institute for Steel Construction (AISC 1989). Also considered in the calculations is the capability of the thick lugs to withstand the weight of the pump together with that of the container and strongback during rotation to the horizontal position

  14. Optimal control of lift/drag ratios on a rotating cylinder

    Science.gov (United States)

    Ou, Yuh-Roung; Burns, John A.

    1992-01-01

    We present the numerical solution to a problem of maximizing the lift to drag ratio by rotating a circular cylinder in a two-dimensional viscous incompressible flow. This problem is viewed as a test case for the newly developing theoretical and computational methods for control of fluid dynamic systems. We show that the time averaged lift to drag ratio for a fixed finite-time interval achieves its maximum value at an optimal rotation rate that depends on the time interval.

  15. The design of steel string crane with lifting capacity 10 tons

    International Nuclear Information System (INIS)

    Syamsurrijal Ramdja

    2007-01-01

    The steel string (sling) used for lift Crane of type of Overhead Travelling Crane, with capacities lifting 10 ton are designed. If compared to other string type, string of steel have some excellence. At this design, election of type of string become primary and the factor of safety become prima facie matter with pursuant to up to date standard. From made of design, is hence got by specification and age of steel string. (author)

  16. Dynamic lift on an artificial static armor layer during highly unsteady open channel flow

    OpenAIRE

    Spiller, Stephan Mark; Ruther, Nils; Friedrich, Heide

    2015-01-01

    The dynamic lift acting on a 100 mm × 100 mm section of a static armor layer during unsteady flow is directly measured in a series of physical experiments. The static armor layer is represented by an artificial streambed mold, made from an actual gravel bed. Data from a total of 190 experiments are presented, undertaken in identical conditions. Results show that during rapid discharge increases, the dynamic lift on the streambed repeatedly exhibits three clear peaks. The magnitude of the obse...

  17. Including the Effect of Shielding in Prediction of Weather Window for Offshore Lifting Operations

    OpenAIRE

    Olsen, Camilla Waldum

    2015-01-01

    The offshore industry is constantly seeking to operate in more extreme conditions. DeepOcean is a subsea service company, where offshore lifts is a part of every day operations. To remain competitive, it is important to reduce operational downtime, where time spent waiting on weather is one of the main contributors. The main goal of this thesis is to investigate how shielding effects influence the operational limit for offshore lifting operations at different heading angles. Common practice i...

  18. The association between lifting an administrative restriction on antidepressant dispensing and treatment patterns in Iceland

    DEFF Research Database (Denmark)

    Thengilsdottir, G; Gardarsdottir, H; Almarsdóttir, Anna Birna

    2013-01-01

    On March 1st 2009, restrictions on the dispensing of selective serotonin reuptake inhibitors (SSRI) in Iceland were lifted. Incident rates and changes in early discontinuation and switching before and after the change were investigated.......On March 1st 2009, restrictions on the dispensing of selective serotonin reuptake inhibitors (SSRI) in Iceland were lifted. Incident rates and changes in early discontinuation and switching before and after the change were investigated....

  19. Candidate Earth Entry Trajectories to Mimic Venus Aerocapture Using a Lifting ADEPT

    Science.gov (United States)

    Williams, Jimmy

    2017-01-01

    A Lifting ADEPT is considered for aerocapture at Venus. Analysis concerning the heating environment leads to an initial sizing estimate. In tandem, a direct entry profile at Earth is considered to act as a facsimile for the Venus aerocapture heating environment. The bounds of this direct entry profile are determined and it is found that a trajectory from a Geostationary Transfer Orbit with a Lifting ADEPT capable of fitting on a rideshare opportunity is capable of matching certain aspects of this heating environment.

  20. Reducing the Lift-Off Effect on Permeability Measurement for Magnetic Plates From Multifrequency Induction Data

    OpenAIRE

    Lu, Mingyang; Zhu, Wenqian; Yin, Liyuan; Peyton, Anthony J.; Yin, Wuliang; Qu, Zhigang

    2017-01-01

    Lift-off variation causes errors in eddy current measurement of nonmagnetic plates as well as magnetic plates. For nonmagnetic plates, previous work has been carried out to address the issue. In this paper, we follow a similar strategy, but try to reduce the lift-off effect on another index--zero-crossing frequency for magnetic plates. This modified index, termed as the compensated zero-crossing frequency, can be obtained from the measured multifrequency inductance spectral data using the alg...