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Constraining the geometry and displacement of crustal‐scale normal faults has historically been challenging, owing to difficulties with geophysical imaging and inability to identify precise cut‐offs at depth. Using a modified workflow previously applied to contractional systems, flexural‐kinematic (Move) and thermal‐kinematic (Pecube) models are integrated with apatite (U‐Th)/He (AHe) and apatite fission track (AFT) data from Teton footwall transects to constrain total Teton fault displacement (Dmax). Models with slip onset at ∼10 Ma and flexure parameters that best match the observed Teton flexural profile require Dmax > 8 km to produce young (<10 Ma) AHe ages observed at low elevation footwall positions in the Tetons. For the same slip onset, models with Dmax of 11–13 km provide the best match to observed AHe data, but displacements ≥16 km are required to produce observed AFT ages (13.6–12.0 Ma) at low elevations. A more complex model with slow slip onset at ∼25 Ma followed by faster slip at ∼10 Ma yields a good match between modeled and observed AHe ages at a Dmax of 13–15 km. However, this model predicts low elevation AFT ages 6–8 Ma older than observed ages, even at Dmax values of 16–17 km. Based on this analysis and integration with previous studies, we propose a unified evolution wherein the Teton fault likely experienced 11–13 km of Miocene‐recent displacement, with AFT data likely indicating a pre‐to early Miocene cooling history. Importantly, this study highlights the utility of using integrated flexural‐ and thermal‐kinematic models to resolve displacement histories in extensional systems. Key Points: Integrating flexural‐ and thermal‐kinematic models with thermochronology data provides constraints on crustal‐scale normal fault evolutionResults show how effective elastic thickness, fault geometry, and detachment depth impact fault evolution and predicted age dataFor the contested displacement history of the Teton fault example, analyses indicate >11 km and potentially >16 km of normal displacement [ABSTRACT FROM AUTHOR]

This paper develops electro-elastic relations of functionally graded cylindrical nanoshell integrated with intelligent layers subjected to multi-physics loads resting on elastic foundation. The piezoelectric layers are actuated with external applied voltage. The nanocore is assumed in-homogeneous in which the material properties are changed continuously and gradually along radial direction. Third-order shear deformation theory is used for the description of kinematic relations and electric potential distribution is assumed as combination of a linear function along thickness direction to show applied voltage and a longitudinal distribution. Electro-elastic size-dependent constitutive relations are developed based on nonlocal elasticity theory and generalized Hooke's law. The principle of virtual work is used to derive governing equations in terms of four functions along the axial and the radial directions and longitudinal electric potential function. The numerical results including radial and longitudinal displacements are presented in terms of basic input parameters of the integrated cylindrical nanoshell such as initial electric potential, small scale parameter, length to radius ratio and two parameters of foundation. It is concluded that both displacements are increased with an increase in small-scale parameter and a decrease in applied electric potential. [ABSTRACT FROM AUTHOR]

Purpose: This study introduces a new approximated analytical solution of the free vibration analysis to evaluate the natural frequencies of functionally graded rectangular sandwich plates with porosities. Design/methodology/approach: The kinematic relations are developed based on the classical plate theory (CPT), and the governing differential equation is derived by employing the Rayleigh-Ritz approximate method. The FGM plate is assumed made of an isotropic material that has an even distribution of porosities. The materials properties varying smoothly in the thickness direction only according to the power-law scheme. Findings: The influences of changing the gradient index, porosity distribution, boundary conditions, and geometrical properties on the free vibration characteristics of functionally graded sandwich plates are analysed. Research limitations/implications: A detailed numerical investigation is carried out using the finite element method with the help of ANSYS 2020 R2 software to validate the results of the proposed analytical solution. Originality/value: The results with different boundary conditions show the influence of porosity distribution on the free vibration characteristics of FG sandwich plates. The results indicated a good agreement between the approximated method such as the Rayleigh-Ritz and the finite element method with an error percentage of no more than 5%. [ABSTRACT FROM AUTHOR]

The purpose of this study was to describe the acceleration variables in a plyometric jump test using the inertial sensor built into an iPhone 4S® smartphone, and the jumping variables from a contact mat. A cross-sectional study was conducted involving 16 healthy young adults. Linear acceleration, flight time, contact time and jump height were measured in a drop jump test from 60 cm and from 30 cm. Greater acceleration values were found in the drop jump test from 60 cm; the same was observed for the values from the contact mat. Multiple regression analysis was performed for each drop jump test: jump height was used as the dependent variable, and the most relevant variables were used as predictor variables (weight and maximum angular velocity in the Y axis for analysis of the drop jump from 60 cm, and weight and maximum acceleration in the Z axis for the drop jump from 30 cm). We found a significant regression model for the drop jump test from 60 cm (R2 = 0.515, p " 0.001) and for the test from 30 cm (R2 = 0.460, p " 0.01). According to the results obtained in this study, the built-in iPhone 4S® inertial sensor is able to measure acceleration for healthy young adults performing a vertical drop jump test. The acceleration kinematic variables are higher in the drop jump test from 60 cm than from 30 cm. [ABSTRACT FROM AUTHOR]

Abstract Accurate and reliable experimental data of a sloshing-induced, rapidly-evolving spilling breaker, are used to understand the specific physics of this phenomenon and to partially evaluate a simplified analytical model by Brocchini and co-workers (Brocchini , 1996; Misra et al., 2004, 2006). Such model is based on a three-layer structure: an underlying potential flow, a thin, turbulent single-phase layer in the middle and a turbulent two-phase layer (air–water) on the upper part. The experiments were carried out by using a 3 m long, 0.6 m deep and 0.10 m wide tank, built in Plexiglas and forced through an hexapode system, this allowing for an high accuracy of the motion. Mean and turbulent kinematic quantities were measured using the Particle Image Velocimetry (PIV) technique. To ensure repeatability of the phenomenon, a suitable breaker event was generated to occur during the first two oscillation cycles of the tank. The tank motion was suitably designed using a potential (HPC) and a Navier–Stokes solver. The latter, was useful to understand the dimension of the area of interest for the measurements. The evolution of the breaker is described in terms of both global and local properties. Wave height and steepness show that after an initial growth, the height immediately decays after peaking, while the wave steepness remains constant around 0.25. The evolution of the local properties, like vorticity and turbulence, vortical and turbulent flows displays the most interesting dynamics. Two main stages characterize such evolution. In stage (1), regarded as a "build-up" stage, vorticity and TKE rapidly reach their maximum intensity and longitudinal extension. During such stage the thickness of the single-phase turbulent region remains almost constant. Stage (2), is regarded as a "relaxation" stage, characterized by some significant flow pulsation till the wave attains a quasi-steady shape. In support to the analytical, three-layer model of Brocchini and co-workers it is demonstrated that the cross-flow profile of the mean streamwise velocity U inside the single-phase turbulent layer is well represented by a cubic polynomial. However, differently from available steady-state models the coefficient of the leading-order term is function of time: A = A (s , t). During stage (1) a fairly streamwise-uniform distribution of U is characterized by A (s , t) ≈ 1 , while during stage (2) U is less uniform and A varies over a much larger range. [ABSTRACT FROM AUTHOR]

A general methodology for ensuring the geometric accuracy of a 6-DOF polishing hybrid robot having a 3UPS and UP parallel mechanism and a 3-DOF wrist is presented. The process is implemented in three steps: formulation of the error model containing complete source errors such as offset errors of the actuated joints and structural errors of the joints and links utilizing product of exponentials formula and screw theory. Measurement of the full pose error twist with a specially designed measurement tool having three reference points was undertaken. Identification of the source errors by a stepwise identification strategy to overcome the ill-conditioned problem arising from the multicollinearity and development of a linearized error compensator was completed. An experiment has been carried out on the prototype, and the results show that, after calibration, a position volumetric error of 0.07 mm and an orientation error of 0.07 degrees can be achieved over the cubic task workspace with repeatability of 0.016 mm and 0.010 degrees. [ABSTRACT FROM AUTHOR]

This paper presents a comparison between different methods for assessing the probability of rocking and overturning of free standing elements, under the action of ground motions of given intensities. The classical Ishiyama criterion is considered and compared with both kinematic linear and non linear analyses recommended by the Italian Standard (i.e. KL and KNL respectively) and with the displacement based approach proposed by Lam-Gad. The main differences among these methods are highlighted and validated on the basis of experimental tests available in literature, by using real seismic records. Then, the different stability criteria are used to obtain overturning stability charts, based on conventional spectra assumed by Eurocode 8 and some considerations concerning the applicability conditions of each method are given. [ABSTRACT FROM AUTHOR]

We present a deformation theory approach to the classification of kinematical Lie algebras in 3 + 1 dimensions and present calculations leading to the classifications of all deformations of the static kinematical Lie algebra and of its universal central extension, up to isomorphism. In addition, we determine which of these Lie algebras admit an invariant symmetric inner product. Among the new results, we find some deformations of the centrally extended static kinematical Lie algebra which are extensions (but not central) of deformations of the static kinematical Lie algebra. This paper lays the groundwork for two companion papers which present similar classifications in dimension D + 1 for all D ⩾ 4 and in dimension 2 + 1. [ABSTRACT FROM AUTHOR]

The rank-summultiple change-point method is a robust statistical procedure designed to search for the optimal number and the location of change points in an arbitrary continue or discrete sequence of values. As such, this procedure can be used to analyse time-series data. Twelve years of robust data sets for the Séchilienne (French Alps) rockslide showa continuous increase in average displacement rate from 50 to 280 mm per month, in the 2004-2014 period, followed by a strong decrease back to 50 mm per month in the 2014-2015 period. When possible kinematic phases are tentatively suggested in previous studies, its solely rely on the basis of empirical threshold values. In this paper, we analyse how the use of a statistical algorithm for change-point detection helps to better understand time phases in landslide kinematics. First,we test the efficiency of the statistical algorithm on geophysical benchmark data, these data sets (stream flows and Northern Hemisphere temperatures) being already analysed by independent statistical tools. Second, we apply the method to 12-yr daily time-series of the Séchilienne landslide, for rainfall and displacement data, from 2003 December to 2015 December, in order to quantitatively extract changes in landslide kinematics. We find two strong significant discontinuities in the weekly cumulated rainfall values: an average rainfall rate increase is resolved in 2012 April and a decrease in 2014 August. Four robust changes are highlighted in the displacement time-series (2008 May, 2009 November-December-2010 January, 2012 September and 2014 March), the 2010 one being preceded by a significant but weak rainfall rate increase (in 2009 November). Accordingly, we are able to quantitatively define five kinematic stages for the Séchilienne rock avalanche during this period. The synchronization between the rainfall and displacement rate, only resolved at the end of 2009 and beginning of 2010, corresponds to a remarkable change (fourfold increase in mean displacement rate) in the landslide kinematic. This suggests that an increase of the rainfall is able to drive an increase of the landslide displacement rate, but that most of the kinematics of the landslide is not directly attributable to rainfall amount. The detailed exploration of the characteristics of the five kinematic stages suggests that the weekly averaged displacement rates are more tied to the frequency or rainy days than to the rainfall rate values. These results suggest the pattern of Séchilienne rock avalanche is consistent with the previous findings that landslide kinematics is dependent upon not only rainfall but also soil moisture conditions (as known as being more strongly related to precipitation frequency than to precipitation amount). Finally, our analysis of the displacement rate time-series pinpoints a susceptibility change of slope response to rainfall, as being slower before the end of 2009 than after, respectively. The kinematic history as depicted by statistical tools opens new routes to understand the apparent complexity of Séchilienne landslide kinematic. [ABSTRACT FROM AUTHOR]

This short paper develops an adaptive compensation control scheme for two physically linked two-wheel-drive mobile robots with multiple actuator faults. Kinematic and dynamic models are first proposed. Then, an adaptive control scheme is designed, which ensures system stability and asymptotic tracking properties. Simulation results verify its effectiveness. [ABSTRACT FROM AUTHOR]

The high specific energy expended in grinding leads to large heat generation in contact zone of grinding wheel and workpiece, which is the great challenge in the grinding. Aiming to reduce the grinding forces and temperature, employing structured wheels has lately become a subject of special interest. Creation of spiral form structures on the surface of grinding wheels is one of the structuring methods showing great advantages in grinding in terms of grinding force and temperature reduction. However, transfer of the spiral form of the wheel surface to the workpiece surface is a problem with this method. This paper focuses on grinding of twist free surfaces by structured grinding wheels. The kinematics of grinding by the structured wheels was analyzed and simulated with the help of MATLAB. It was found that the ratio of the grinding wheel rotational speed to the workpiece rotational speed plays the key role in grinding of twist free surfaces. The experimental results proved that using the kinematic simulation, the appropriate grinding parameters could be derived to grind a twist free surface. [ABSTRACT FROM AUTHOR]

To investigate the contribution of higher-order nonlinearity and dissipation to nonlinear ultra-lowfrequency dust-acoustic shock waves (DASWs), a reductive perturbation technique is employed in a strongly coupled cryogenic dusty plasma. The model consists of Boltzmann distributed electrons and ions, as well as equations for strongly coupled charged dust grains. A nonlinear Burger equation and a linear inhomogeneous Burger-type equation are derived. The present model admits both compressive and rarefactive dust-acoustic (DA) shocks. Including these higher-order corrections results in creating new shock wave structures called "humped DASWs." It is shown that the effects of kinematic viscosity, the number of electrons residing on the dust grain surface, Zd and the dust number density via β have important roles in the basic features of the produced DA shocks and the associated electric fields. It has been shown that it is more important to be included. These findings are devoted to explaining the observed waves propagating in the laboratory plasma experiments at cryogenic temperature. This kind of plasma is used for etching nano-patterns without defects, used in nonideal systems and physics of nucleation to deposit nanosize Si compounds. [ABSTRACT FROM AUTHOR]

Background: Robot-assisted gait therapy is increasingly being used in pediatric neurorehabilitation to complement conventional physical therapy. The robotic device applied in this study, the Lokomat (Hocoma AG, Switzerland), uses a position control mode (Guidance Force), where exact positions of the knee and hip joints throughout the gait cycle are stipulated. Such a mode has two disadvantages: Movement variability is restricted, and patients tend to walk passively. Kinematic variability and active participation, however, are crucial for motor learning. Recently, two new control modes were introduced. The Path Control mode allows the patient to walk within a virtual tunnel surrounding the ideal movement trajectory. The FreeD was developed to support weight shifting through mediolaterally moveable pelvis and leg cuffs. The aims of this study were twofold: 1) To present an overview of the currently available control modes of the Lokomat. 2) To evaluate if an increase in kinematic variability as provided by the new control modes influenced leg muscle activation patterns and intensity, as well as heart rate while walking in the Lokomat.Methods: In 15 adolescents with neurological gait disorders who walked in the Lokomat, 3 conditions were compared: Guidance Force, Path Control, and FreeD. We analyzed surface electromyographic (sEMG) activity from 5 leg muscles of the more affected leg and heart rate. Muscle activation patterns were compared with norm curves.Results: Several muscles, as well as heart rate, demonstrated tendencies towards a higher activation during conditions with more kinematic freedom. sEMG activation patterns of the M.rectus femoris and M.vastus medialis showed the highest similarity to over-ground walking under Path Control, whereas walking under FreeD led to unphysiological muscle activation in the tested sample.Conclusions: Results indicate that especially Path Control seems promising for adolescent patients undergoing neurorehabilitation, as it increases proximal leg muscle activity while facilitating a physiological muscle activation. Therefore, this may be a solution to increase kinematic variability and patients' active participation in robot-assisted gait training. [ABSTRACT FROM AUTHOR]

In this paper, we address the identifiability of constitutive parameters of passive or active microswimmers. We first present a general framework for describing fibres or micro-swimmers using a bead-model description. Using a kinematic constraint formulation to describe fibres, flagellum or cilia, we find explicit linear relationship between elastic constitutive parameters and generalized velocities from computing contact forces. This linear formulation then permits one to address explicitly identifiability conditions and solve for parameter identification. We show that both active forcing and passive parameters are both identifiable independently but not simultaneously. We also provide unbiased estimators for generalized elastic parameters in the presence of Langevin-like forcing with Gaussian noise using a Bayesian approach. These theoretical results are illustrated in various configurations showing the efficiency of the proposed approach for direct parameter identification. The convergence of the proposed estimators is successfully tested numerically. [ABSTRACT FROM AUTHOR]

In this paper, we present our results for the photometric and kinematical studies of old open cluster NGC 188. We determined various astrophysical parameters like limited radius, core and tidal radii, distance, luminosity and mass functions, total mass, relaxation time etc. for the cluster using 2MASS catalog. We obtained the cluster’s distance from the Sun as 1721 ± 41 pc and log (age)= 9.85 ± 0.05 at Solar metallicity. The relaxation time of the cluster is smaller than the estimated cluster age which suggests that the cluster is dynamically relaxed. Our results agree with the values mentioned in the literature. We also determined the clusters apex coordinates as (281°.88, − 44 ∘ .76) using AD-diagram method. Other kinematical parameters like space velocity components, cluster center and elements of Solar motion etc. have also been computed. [ABSTRACT FROM AUTHOR]

The concept of single-frequency, dual-system (SF-DS) real-time kinematic (RTK) positioning has become feasible since, for instance, the Chinese BeiDou Navigation Satellite System (BDS) has become operational in the Asia-Pacific region. The goal of the present contribution is to investigate the single-epoch RTK performance of such a dual-system and compare it to a dual-frequency, single-system (DF-SS). As the SF-DS we investigate the L1 GPS + B1 BDS model, and for DF-SS we take L1, L2 GPS and B1, B2 BDS, respectively. Two different locations in the Asia-Pacific region are analysed with varying visibility of the BDS constellation, namely Perth in Australia and Dunedin in New Zealand. To emphasize the benefits of such a model we also look into using low-cost ublox single-frequency receivers and compare such SF-DS RTK performance to that of a DF-SS, based on much more expensive survey-grade receivers. In this contribution a formal and empirical analysis is given. It will be shown that with the SF-DS higher elevation cut-off angles than the conventional $$10^{\circ }$$ or $$15^{\circ }$$ can be used. The experiment with low-cost receivers for the SF-DS reveals (for the first time) that it has the potential to achieve comparable ambiguity resolution performance to that of a DF-SS (L1, L2 GPS), based on the survey-grade receivers. [ABSTRACT FROM AUTHOR]

This paper proposes a computationally efficient, novel and superior nonlinear controller to the existing trajectory and orientation (T&O) control problem of an omnidirectional robot (ODR). Here first, the position and orientation (pose) estimation of the robot were obtained utilizing kinematic relationships of the ODR and multi-sensor fusion techniques. Then, dynamic relationships of the robot were used to form its state-space representation. The nonlinear state-space representation (NLSSR) was linearized by identifying and controlling the nonlinearity causing states. Then that linearized NLSSR was utilized to derive a state feedback controller and a proportional derivative integral (PID) controller to carry out a T&O tracking task. Performances of both derived controllers were evaluated in the simulation level comparing with a standard nonlinear controller. From the two proposed controllers, the best-performing, state feedback-based controller was able to be successfully implemented on a low-cost hardware platform due to its computational efficiency. [ABSTRACT FROM AUTHOR]

Although parallel manipulators provide several benefits compared to similar-sized serial manipulators, they typically exhibit a limited rotational workspace. One approach to designing a parallel manipulator with infinite range of tool rotation around one axis is to introduce kinematic redundancy. This is typically achieved by extending a non-redundant mechanism with an additional actuator and a supplemental degree of freedom, while the degrees of freedom of the tool platform remain the same. The main drawback of this approach is the cost of the additional actuator. In this paper, we discuss the possibility of harvesting the motion in the additional degree of freedom to operate a gripper. The benefits of the proposed idea include saving the cost of a gripper actuator and reducing the mass of the manipulated platform. Additionally, the requirement to provide the manipulated platform with compressed air or electric power is removed. Several variants of a kinematically redundant manipulated platform with five degrees of freedom are introduced along with conceptual mechanical designs for transforming the redundant platform motion into the opening and closing of a gripper. [ABSTRACT FROM AUTHOR]

It has been observed in the literature that as the cardinality of the prescribed discrete input–output data set increases, the corresponding four-bar linkages that minimise the Euclidean norm of the design and structural errors tend to converge to the same linkage. The important implication is that minimising the Euclidean norm, or any p -norm, of the structural error, which leads to a nonlinear least-squares problem requiring iterative solutions, can be accomplished implicitly by minimising that of the design error, which leads to a linear least-squares problem that can be solved directly. Apropos, the goal of this paper is to take the first step towards proving that as the cardinality of the data set tends towards infinity the observation is indeed true. In this paper we will integrate the synthesis equations in the range between minimum and maximum input values, thereby reposing the discrete approximate synthesis problem as a continuous one. Moreover, we will prove that a lower bound of the Euclidean norm, and indeed of any p -norm, of the design error for planar RRRR function-generating linkages exists and is attained with continuous approximate synthesis. [ABSTRACT FROM AUTHOR]

Currently, researches on planar gears (including cylindrical gear, noncircular gear) are primarily concerned with those of fixed center distance, that is, the center distance between two meshing gears remains unchanged during the driving process, while those of variable center distance are rarely touched upon. Although not widely applied as fixed center distance gear is, variable center distance gear can be found in noncircular gear shaping and high-torque hydraulic motor, exhibiting unique mechanical properties. This paper focuses on a systematic revelation of the driving principle and mechanical properties of this special variable center distance gear type. On the basis of screw theory, this paper first establishes its mathematical model, including kinematic relations, instantaneous screw axis, “non-conjugated” pitch curves, generator, envelope surfaces and generated surfaces. And then, the mechanical properties, forms as well as advantages of applicable variable center distance gear train are all discussed. [ABSTRACT FROM AUTHOR]

Thought experiments are widely used in informal explanations of Relativity Theories; however, they are not present explicitly in formalized versions of Relativity Theory. In this paper, we present an axiom system of Special Relativity which is able to express thought experiments formally and explicitly. Moreover, using these thought experiments, we can provide an explicit definition of relativistic mass based merely on kinematical concepts and thought experiments on collisions. Using this definition, we can geometrically prove the Mass Increase Formula $$m_0 = m \mathrel {\cdot }\sqrt{1-v^2}$$ in a natural way, without postulates of conservation of mass and momentum. [ABSTRACT FROM AUTHOR]

Rotations of the line of sight are mainly implemented by coordinated motion of the eyes and head. Here, we propose a model for the kinematics of three-dimensional (3-D) head-unrestrained gaze-shifts. The model was designed to account for major principles in the known behavior, such as gaze accuracy, spatiotemporal coordination of saccades with vestibulo-ocular reflex (VOR), relative eye and head contributions, the non-commutativity of rotations, and Listing's and Fick constraints for the eyes and head, respectively. The internal design of the model was inspired by known and hypothesized elements of gaze control physiology. Inputs included retinocentric location of the visual target and internal representations of initial 3-D eye and head orientation, whereas outputs were 3-D displacements of eye relative to the head and head relative to shoulder. Internal transformations decomposed the 2-D gaze command into 3-D eye and head commands with the use of three coordinated circuits: (1) a saccade generator, (2) a head rotation generator, (3) a VOR predictor. Simulations illustrate that the model can implement: (1) the correct 3-D reference frame transformations to generate accurate gaze shifts (despite variability in other parameters), (2) the experimentally verified constraints on static eye and head orientations during fixation, and (3) the experimentally observed 3-D trajectories of eye and head motion during gaze-shifts. We then use this model to simulate how 2-D eye-head coordination strategies interact with 3-D constraints to influence 3-D orientations of the eye-in-space, and the implications of this for spatial vision. [ABSTRACT FROM AUTHOR]

Reheating is the epoch which connects inflation to the subsequent hot big-bang phase. Conceptually very important, this era is, however, observationally poorly known. We show that the current Planck satellite measurements of the cosmic microwave background (CMB) anisotropies constrain the kinematic properties of the reheating era for most of the inflationary models. This result is obtained by deriving the marginalized posterior distributions of the reheating parameter for about 200 models of slow-roll inflation. Weighted by the statistical evidence of each model to explain the data, we show that the Planck 2013 measurements induce an average reduction of the posterior-to-prior volume by 40%. Making some additional assumptions on reheating, such as specifying a mean equation of state parameter, or focusing the analysis on peculiar scenarios, can enhance or reduce this constraint. Our study also indicates that the Bayesian evidence of a model can substantially be affected by the reheating properties. The precision of the current CMB data is therefore such that estimating the observational performance of a model now requires incorporating information about its reheating history. [ABSTRACT FROM AUTHOR]

In this paper, we outline a method to compute supersymmetric one-loop integrands in ten-dimensional SYM theory. It relies on the constructive interplay between their cubic-graph organization and BRST invariance of the underlying pure spinor superstring description. The five- and six-point amplitudes are presented in a manifestly local form where the kinematic dependence is furnished by BRST-covariant expressions in pure spinor superspace. At five points, the local kinematic numerators are shown to satisfy the BCJ duality between color and kinematics leading to type IIA/B supergravity amplitudes as a byproduct. At six points, the sources of the hexagon anomaly are identified in superspace as systematic obstructions to BRST invariance. Our results are expected to reproduce any integrated SYM amplitude in dimensions [ABSTRACT FROM AUTHOR]

High temporal and vertical resolutions of kinematic and thermodynamic characteristics of a late-mature gust front are presented using the Mobile Integrated Profiling System and Weather Surveillance Radar 88 Doppler data. As the gust front passed over the Mobile Integrated Profiling System vertical velocities and the horizontal wind field with 1 and 1.5 min temporal resolutions, respectively, were sampled within the gust front updrafts, gust frontal head and body structures. A 12-channel microwave profiling radiometer was used to delineate the thermodynamic properties with 5-6 min temporal and 100 m vertical resolution. Lidar backscatter from the 0.906 $\upmu$m ceilometer was also used to demonstrate the cloud field and the gust front depth. The gust front structurally and dynamically resembled laboratory simulated density current, and was composed of an elevated forward protrusion of a nose, and a turbulent mixing region at the top behind the head. The updrafts associated with the gust front that was moving into a stable layer were not surface rooted. Rather, the updrafts less than 3.5 ms were observed 500 m above ground level during the gust front passage. These updrafts were present from above the nose level to top of the head. The observations indicated that kinematic and thermodynamic characteristics of the atmospheric boundary layer significantly influenced the propagation speed, updraft characteristics, and overall structural organization of the gust front. The observations validated that observed propagation speed of the gust front was in close agreement with the calculated propagation speed by integrating the buoyancy term within the gust front depth. [ABSTRACT FROM AUTHOR]

The approach regarding the plastic process as a constrained optimization problem (Simo, J. C., and Hughes, T. J. R., 1998, Computational Inelasticity, Springer, New York) is discussed and found to be limited in considering nonlinear kinematic hardening and mechanical dissipation. These limitations are virtually common in elastoplastic modeling in both theoretical studies and industrial applications. A modified maximum mechanical dissipation principle is proposed to overcome the limitations and form an energy-based framework of nonlinear hardening laws. With the control functions introduced into the framework, not only are the relationships between existing hardening models clarified against their ad hoc origins, but modeling nonsaturating kinematic hardening behavior is also achieved. Numerical examples are presented to illustrate the capability of the nonsa-turating kinematic hardening model to describe the phenomena of the permanent softening as well as the cyclic loading. These applications indicate the concept of the control function can be nontrivial in material modeling. Finally, the methodology is also extended to incorporate the multiterm approach. [ABSTRACT FROM AUTHOR]

Motor extinction refers to a deficit of motor production on the side opposite a brain lesion that either only becomes apparent or disproportionately worsens during bilateral motor activity. It may arise due either to a contralesional deficit in setting the motor activation level (an intentional deficit) or a deficit in contralesional awareness of the sensory consequences of movement (an attentional deficit). In this study, we investigate the nature of motor extinction in a patient (LR) with a right fronto-temporal lesion through the kinematic analysis of unimanual and bimanual circle drawing movements. While the ipsi- and contralesional limbs performed comparably for unimanual movements, the contralesional limb demonstrated marked bradykinesia and hypometria during bimanual movements. Furthermore, these deficits were not overcome when visual feedback of the contralesional limb was provided (Experiment 1). However, when performing bimanual movements in the presence of a visual template (Experiment 2), LR was able to overcome the contralesional hypometria but not the bradykinesia which proved intractable across both experiments. Both the bradykinesia and hypometria could result from an intentional deficit of motor production. However, in Experiment 2, LR also demonstrated an abnormal level of positional drift in the contralesional limb for bimanual movements indicative of an additional attentional deficit. We conclude that LR's presentation of motor extinction is the result of a primary intentional deficit and a secondary attentional deficit. [ABSTRACT FROM AUTHOR]

This paper presents the development of flexible wings, flapping mechanism, and integrated electronic control system (ECS) to emulate the bat wing flapping for the ongoing micro air vehicle (MAV) research. Three bat species having dimensions close to the design requirement of MAV, namely, Mormopterus Planiceps, Nytophilus Geoffroyi, and Scotorepens Balstoni were selected, and the average of their physical dimensions was chosen. The commercially available titanium alloy, Ti ± 6Al ± 4V, was used for the wing frame, and the membrane was made of latex. A four-bar slider-crank mechanism was designed and fabricated to facilitate the wing flapping; ECS controlled the flapping frequency in the real-time mode. The system was tested in open air wind tunnel at frequency 6 Hz, angle of attack (AOA) 0-50°, and velocity range 2-7 m s−1. The experimental flapping angle which is compared with the theoretical flapping angle was obtained from the analytical kinematic model. The mean lift and drag coefficients were also measured and the results were found to be excellent. Compared to the manual control and measurement of flapping frequency, the proposed ECS demonstrates efficient control and accurate measurement. Moreover, the tedious procedure involved in the repeated calibrations for the manual system is totally eliminated by ECS. [ABSTRACT FROM AUTHOR]

The South Atlantic rift basin evolved as a branch of a large Jurassic-Cretaceous intraplate rift zone between the African and South American plates during the final break-up of western Gondwana. While the relative motions between South America and Africa for post-break-up times are well resolved, many issues pertaining to the fit reconstruction and particularly the relation between kinematics and lithosphere dynamics during pre-break-up remain unclear in currently published plate models. We have compiled and assimilated data from these intraplated rifts and constructed a revised plate kinematic model for the pre-break-up evolution of the South Atlantic. Based on structural restoration of the conjugate South Atlantic margins and intracontinental rift basins in Africa and South America, we achieve a tight-fit reconstruction which eliminates the need for previously inferred large intracontinental shear zones, in particular in Patagonian South America. By quantitatively accounting for crustal deformation in the Central and West African Rift Zones, we have been able to indirectly construct the kinematic history of the pre-break-up evolution of the conjugate west African-Brazilian margins. Our model suggests a causal link between changes in extension direction and velocity during continental extension and the generation of marginal structures such as the enigmatic presalt sag basin and the São Paulo High. We model an initial E-W-directed extension between South America and Africa (fixed in present-day position) at very low extensional velocities from 140Ma until late Hauterivian times (≈ 126 Ma) when rift activity along in the equatorial Atlantic domain started to increase significantly. During this initial ≈ 14 Myrlong stretching episode the pre-salt basin width on the conjugate Brazilian and west African margins is generated. An intermediate stage between ≈ 126 Ma and base Aptian is characterised by strain localisation, rapid lithospheric weakening in the equatorial Atlantic domain, resulting in both progressively increasing extensional velocities as well as a significant rotation of the extension direction to NE-SW. From base Aptian onwards diachronous lithospheric breakup occurred along the central South Atlantic rift, first in the Sergipe-Alagoas/Rio Muni margin segment in the northernmost South Atlantic. Final break-up between South America and Africa occurred in the conjugate Santos-Benguela margin segment at around 113 Ma and in the equatorial Atlantic domain between the Ghanaian Ridge and the Piauí-Ceará margin at 103 Ma. We conclude that such a multi-velocity, multi-directional rift history exerts primary control on the evolution of these conjugate passive-margin systems and can explain the first-order tectonic structures along the South Atlantic and possibly other passive margins. [ABSTRACT FROM AUTHOR]

We present a homogeneous kinematic analysis of red giant branch stars within 18 of the 28 Andromeda dwarf spheroidal (dSph) galaxies, obtained using the Keck I/LRIS and Keck II/DEIMOS spectrographs. Based on their g - i colors (taken with the CFHT/MegaCam imager), physical positions on the sky, and radial velocities, we assign probabilities of dSph membership to each observed star. Using this information, the velocity dispersions, central masses, and central densities of the dark matter halos are calculated for these objects, and compared with the properties of the MilkyWay dSph population.We also measure the average metallicity ([Fe/H]) from the co-added spectra of member stars for each M31 dSph and find that they are consistent with the trend of decreasing [Fe/H] with luminosity observed in the Milky Way population. We find that three of our studied M31 dSphs appear as significant outliers in terms of their central velocity dispersion, And XIX, XXI, and XXV, all of which have large half-light radii (≳700 pc) and low velocity dispersions (σv < 5kms-1). In addition, And XXV has a mass-to-light ratio within its half-light radius of just [M/Llhalf = 10.3+7.0 -6.7, making it consistent with a simple stellar system with no appreciable dark matter component within its 1σ uncertainties. We suggest that the structure of the dark matter halos of these outliers have been significantly altered by tides. [ABSTRACT FROM AUTHOR]

The polarizations of the Y(1S), Y(2S), and Y(3S) mesons are measured in protonproton collisions at √s = 7 TeV, using a data sample of Y(nS) → μ+μ- decays collected by the CMS experiment, corresponding to an integrated luminosity of 4.9 fb-1. The dimuon decay angular distributions are analyzed in three different polarization frames. The polarization parameters λϑ, λφ and λϑφ, as well as the frame-invariant quantity ̃λ, are presented as a function of the Y(nS) transverse momentum between 10 and 50 GeV, in the rapidity ranges ∣y∣ < 0.6 and 0.6 < ∣y∣ < 1.2. No evidence of large transverse or longitudinal polarizations has been seen in the explored kinematic region. [ABSTRACT FROM AUTHOR]

Evidence is presented for the associated production of a single top quark and W boson in pp collisions at √s = 7 TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 4.9 fb-1. The measurement is performed using events with two leptons and a jet originated from a b quark. A multivariate analysis based on kinematic properties is utilized to separate the tt background from the signal. The observed signal has a significance of 4.0s and corresponds to a cross section of 16+5-4 pb, in agreement with the standard model expectation of 15.6 ± 0.4+1.0-1.2 pb. [ABSTRACT FROM AUTHOR]

ABSTRACT The isolation, simple apparent structure and low luminosity of the nearby spiral galaxy NGC 6503 make it an ideal candidate for an in-depth kinematic and photometric study. We introduce a new publicly available code, D iskF it, that implements procedures for fitting non-axisymmetries in either kinematic or photometric data. We use D iskF it to analyse new Hα and CO velocity field data as well as H i kinematics from Greisen et al. to search for non-circular motions in the disc of NGC 6503. We find NGC 6503 to have remarkably regular gas kinematics that are well described by rotation only. We also use D iskF it and a new Ks-band image of NGC 6503 to constrain photometric models of the disc, bar and bulge. We find the galaxy to be photometrically dominated by the disc. We find NGC 6503 to contain a faint bar and an exponential bulge which together contribute only ∼5 per cent of the total galaxy light. The combination of our kinematic and photometric D iskF it models suggests that NGC 6503 contains a weak, end-on bar that may have produced its Type II surface brightness profile but is unlikely to be responsible for its strong σ-drop. [ABSTRACT FROM AUTHOR]

Abstract: As a special approach to orbit determination for satellites with spaceborne GPS receivers, the kinematic Precise Orbit Determination (POD) is independent of any mechanical model (e.g., the Earth gravity field, atmospheric drag, solar radiation pressure, etc.), and thus especially suitable for the orbit determination of Low Earth Orbiting (LEO)satellites perturbed strongly bythe atmosphere. In this paper, based on the space-borne dual-frequency GPS data, we study the kinematic POD, discuss the pre-processing of the data, and construct an algorithm of zero-difference kinematic POD. Using the observational data from GRACE (Gravity Recovery And Climate Experiment) satellites covering the whole month of February 2008, we verify the effectiveness and reliability of this algorithm. The results show that the kinematic POD may attain an accuracy of about 5cm (with respect to satellite laser ranging data), which is at the same level as the dynamic and reduced-dynamic PODs [Copyright &y& Elsevier]

Abstract: The radiative decay has been studied at ISTRA+ setup in a new kinematic region. About 22K events of have been observed. The sign and value of have been measured for the first time. The result is . [Copyright &y& Elsevier]

Abstract: Establishment of a geodetic network in Tenerife is the starting point for the use of GPS and other precise geodetic techniques in the support of the study of kinematics and their relation with island volcanic activity. This paper is focused on the characterization of volcanotectonic activity of Tenerife, to determine the geodynamic framework for volcanic surveillance. TEGETEIDE network, set up in 2005 and re-observed each year, is composed of seven GNSS–GPS stations scattered throughout the island. A horizontal deformation model is presented in order to explain the observed island displacement pattern in the geodynamic context of the Nubian plate. According to the models obtained, the most important geologic structures, such as the volcanic rifts and the caldera, determine the current deformation pattern of Tenerife. The geodynamics of the most stable areas of the island behave similarly to that observed from the permanent GNSS–GPS reference stations located in La Palma and Gran Canaria Islands. Anomalous geodynamic behaviour has been detected in two zones of Tenerife, which configure an NW–SE axis crossing the central sector of the island, related with the volcanotectonic activity of the island and its surroundings. [ABSTRACT FROM AUTHOR]

A consistent procedure for mapping the global positioning system (GPS) from Earth's frame to the solar barycentric frame is developed. The process is first analyzed in reverse, i.e., by a general mapping from the solar frame to Earth centered inertial frame. In the process of developing the correct mapping, several peripheral issues are addressed. These include (1) an analysis of the Sagnac effect, which is generally incorrectly ascribed to a rotational effect, and (2) an analysis of Thomas precession, which is generally incorrectly ascribed to infinitesimal Lorentz transformations. The true transformation between the solar frame and the ECI frame is shown to be a combination of a Selleri transformation and clock bias effects due to velocity and gravitational potentials which combine to form an apparent Lorentz transformation (ALT). The longitudinal length contraction effects embedded within the Selleri transformation are shown to be the result of the conservation of momentum. There are several significant differences between the ALT and the Lorentz transformation (LT). First, sequential noncollinear ALTs do not induce rotational effects such as sequential noncollinear LTs. Second, there is a natural change of scale in the ALT but not in the LT. In addition, momentum and energy are conserved in the ALT but not in the LT. The reverse ALT is derived and it differs from the reverse LT in that the original scaling is recovered by the reverse ALT but compounded by the reverse LT. Finally, it is shown that the use of space based very long baseline interferometry (VLBI) may provide a means to verify the derived ALT mapping procedure by revealing the longitudinal orbital contraction, which is obscured in visual and electromagnetic experiments but revealed in precise VLBI angular measurements. [ABSTRACT FROM AUTHOR]

The Bianchi type-V cosmological models have been investigated in the context of Brans–Dicke theory in the presence as well as absence of the magnetic field. The physical and kinematical behaviors of the models have been discussed. The energy conditions of the models have also been examined. [ABSTRACT FROM AUTHOR]

Multi Degree of Freedom (DOF) planar kinematic chains can be considered for application as parallel robots in view of their greater rigidity. A large number of distinct chains are available with the same number of links and DOF for consideration as parallel structures. Hence, it becomes necessary to know which of these chains more parallel so that the selection of these chains for the specified tasks like workspace and rigidity becomes easy. A simple and logical method is presented in this paper to accomplish the same. The measure of compactness developed in this paper enables comparison of distinct chains for these characteristics. [ABSTRACT FROM AUTHOR]

This paper proposes a method that combines compact real-time kinematic (RTK) and reference station (RS) networking techniques, and shows that this approach can reduce both the temporal and spatial decorrelation error. The compact RTK method compatibility with all the conventional network RTK systems, i.e., Master-Auxiliary Concept (MAC), Virtual Reference Stations (VRS), and Flächen-Korrektur Parameter (FKP), is examined theoretically in this paper. To prove that the compact RTK approach is not only valid, but also helpful to the network RTK system, a field test was held using one hour of Receiver Independent Exchange Format (RINEX) data logged every second from Continuously Operating Reference Stations (CORS). No matter which network RTK method is applied, the Compact Network RTK approach resolves the ambiguity of the carrier phase in 10-40 s and determines position with 6-7 cm horizontal and 7-8 cm vertical error (95%) in a 100 by 100 km region. Moreover, the Compact Network RTK approach enables network RTK service providers to reduce the data-link bandwidth for correction messages to 5-700 bps (bit/s) down from several thousand bps, currently 9600 bps of GPRS/GSM, without a severe degradation of accuracy. [ABSTRACT FROM AUTHOR]

An updated inverse approach with discrete Kirchhoff quadrilateral (DKQ) element is proposed to consider actual process conditions such as friction, blank-holder force, pad force, and draw-bead restraining force, which improves the calculation accuracy and extends the application scopes of the inverse approach. Based on the updated approach, a trimming line design and flanging analysis method are proposed. These methods can be used in autopanel virtual manufacturing, rapid design, and manufacturing as quick simulation and optimization tools. Some practical examples are presented to verify the accuracy and the efficiency of the methods. [ABSTRACT FROM AUTHOR]

Background: The advances in technology make possible the incorporation of sensors and actuators in rollators, building safer robots and extending the use of walkers to a more diverse population. This paper presents a new method for the extraction of navigation related components from upper-body force interaction data in walker assisted gait. A filtering architecture is designed to cancel: (i) the highfrequency noise caused by vibrations on the walker's structure due to irregularities on the terrain or walker's wheels and (ii) the cadence related force components caused by user's trunk oscillations during gait. As a result, a third component related to user's navigation commands is distinguished. Results: For the cancelation of high-frequency noise, a Benedict-Bordner g-h filter was designed presenting very low values for Kinematic Tracking Error ((2.035 ± 0.358)·10-2 kgf) and delay ((1.897 ± 0.3697)·101ms). A Fourier Linear Combiner filtering architecture was implemented for the adaptive attenuation of about 80% of the cadence related components' energy from force data. This was done without compromising the information contained in the frequencies close to such notch filters. Conclusions: The presented methodology offers an effective cancelation of the undesired components from force data, allowing the system to extract in real-time voluntary user's navigation commands. Based on this real-time identification of voluntary user's commands, a classical approach to the control architecture of the robotic walker is being developed, in order to obtain stable and safe user assisted locomotion. [ABSTRACT FROM AUTHOR]

In the past several years kinematic data sets from Milky Way satellite galaxies have greatly improved, furthering the evidence that these systems are the most dark matter dominated objects known. This paper discusses a maximum likelihood formalism that extracts important quantities from these kinematic data sets, including the amplitude of a rotational signal, proper motions, and the mass distributions. Using a simple model for galaxy rotation it is shown that the expected error on the amplitude of a rotational signal is ∼0.5 km s-1 with ∼10³ stars from either classical or ultra-faint satellites. As an example Sculptor is analyzed for the presence of a rotational signal; no significant detection of rotation is found, with a 90% c.l. upper limit of ∼2 km s-1. A criterion for model selection is presented that determines the parameters required to describe the dark matter halo density profiles and the stellar velocity anisotropy. Applied to four data sets with a wide range of velocities, models with variable velocity anisotropy are preferred relative to those with constant velocity anisotropy, and that central dark matter profiles both less cuspy and more cuspy than Lambda-Cold Dark Matter-based fits are equally acceptable. [ABSTRACT FROM AUTHOR]

Cosmology has always been different from other areas of the natural sciences. Although an observationally supported standard model of the universe emerged in the 1960s, more speculative models and conceptions continued to attract attention. During the last decade, ideas of multiple universes (the 'multiverse') based on anthropic reasoning have become very popular among cosmologists and theoretical physicists. This had led to a major debate within the scientific community of the epistemic standards of modern cosmology. Is the multiverse a scientific hypothesis, or is it rather a philosophical speculation disguised as science? This paper offers a review of the recent and still ongoing controversy concerning the multiverse, emphasizing its foundational nature and relation to philosophical issues. It also compares the multiverse controversy to some earlier episodes in the history of twentieth-century cosmology when particular theories and approaches came under attack for betraying the ideals of proper science. [ABSTRACT FROM AUTHOR]