Articles de revues : « Moment prior »

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William S. Jewell et Rene Schnieper. « Credibility Approximations for Bayesian Prediction of Second Moments ». ASTIN Bulletin 15, n^o 2 (novembre 1985) : 103–21. http://dx.doi.org/10.2143/ast.15.2.2015022.

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AbstractCredibility theory refers to the use of linear least-squares theory to approximate the Bayesian forecast of the mean of a future observation; families are known where the credibility formula is exact Bayesian. Second-moment forecasts are also of interest, for example, in assessing the precision of the mean estimate. For some of these same families, the second-moment forecast is exact in linear and quadratic functions of the sample mean. On the other hand, for the normal distribution with normal-gamma prior on the mean and variance, the exact forecast of the variance is a linear function of the sample variance and the squared deviation of the sample mean from the prior mean. Bühlmann has given a credibility approximation to the variance in terms of the sample mean and sample variance.In this paper, we present a unified approach to estimating both first and second moments of future observations using linear functions of the sample mean and two sample second moments; the resulting least-squares analysis requires the solution of a 3 × 3 linear system, using 11 prior moments from the collective and giving joint predictions of all moments of interest. Previously developed special cases follow immediately. For many analytic models of interest, 3-dimensional joint prediction is significantly better than independent forecasts using the “natural” statistics for each moment when the number of samples is small. However, the expected squared-errors of the forecasts become comparable as the sample size increases.

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Ioan, Augustin. « Archives : Building-in Time ». Diakrisis Yearbook of Theology and Philosophy 5 (31 juillet 2022) : 117–33. http://dx.doi.org/10.24193/diakrisis.2022.7.

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The zero-moment of an architectural undertaking precedes and the final one postpones the conventional moments of building and demolition. This pre-usage of the material and of the site turn the ‘birth’ of the house into a rather vague moment. In the numerous makings there exist prior makings, and sites often appear to be palimpsests, layer upon layer, erasure upon erasure. This manner of approaching the question of the temporal ‘sponginess’ of architecture recalls the question concerning the beginnings of architecture. In this chain of fertile ‘blackouts’, the ‘origin’ of architecture ceases to be the inaugural moment still sought to this day: in a making there exist prior makings, and in an unmaking there endures the chance of future lives, at least in principle. Moreover, the question ‘when?’ deserves another, probably more fertile for the economy of this text: ‘For how long?’

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Crisco, Joseph J., Nikolas J. Osvalds et Michael J. Rainbow. « The Kinetics of Swinging a Baseball Bat ». Journal of Applied Biomechanics 34, n^o 5 (1 octobre 2018) : 386–91. http://dx.doi.org/10.1123/jab.2017-0337.

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The purpose of this study was to compute the 3-dimensional kinetics required to swing 3 youth baseball bats of varying moments of inertia. The 306 swings by 22 male players (age 13–18 y) were analyzed. Inverse dynamics with respect to the batter’s hands were computed given the known kinematics and physical properties of the bats. Peak force increased with larger bat moments of inertia and was strongly correlated with bat tip speed. By contrast, peak moments were weakly correlated with bat moments of inertia and bat tip speed. Throughout the swing, the force applied to the bat was dominated by a component aligned with the long axis of the bat and directed away from the bat knob, whereas the moment applied to the bat was minimal until just prior to ball impact. These results indicate that players act to mostly “pull” the bat during their swing until just prior to ball impact, at which point they rapidly increase the moment on the bat. This kinetic analysis provides novel insight into the forces and moments used to swing baseball bats.

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Phillips, David L. « Watershed moment in US-Turkey relations ». Commentaries 1, n^o 1 (27 novembre 2021) : 23–30. http://dx.doi.org/10.33182/tc.v1i1.1993.

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President Joe Biden recognized atrocities committed against Armenians as the Armenian Genocide in his statement on Armenian Genocide Remembrance Day (24 April 2021). The statement represents a watershed moment in US-Turkey relations. President Tayyip Erdogan can address US and international concerns prior to the Biden-Erdogan summit on the margin of June’s NATO meeting, or he can double down and intensify repression against Turkey’s ethnic and religious minorities. Erdogan’s course will define international relations prior to the centennial of the founding of the Turkish republic in 2023.

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Kruk, Łukasz. « Limiting distributions for minimum relative entropy calibration ». Journal of Applied Probability 41, n^o 1 (mars 2004) : 35–50. http://dx.doi.org/10.1239/jap/1077134666.

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We consider minimum relative entropy calibration of a given prior distribution to a finite set of moment constraints. We show that the calibration algorithm is stable (in the Prokhorov metric) under a perturbation of the prior and the calibrated distributions converge in variation to the measure from which the moments have been taken as more constraints are added. These facts are used to explain the limiting properties of the minimum relative entropy Monte Carlo calibration algorithm.

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Kruk, Łukasz. « Limiting distributions for minimum relative entropy calibration ». Journal of Applied Probability 41, n^o 01 (mars 2004) : 35–50. http://dx.doi.org/10.1017/s0021900200014029.

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We consider minimum relative entropy calibration of a given prior distribution to a finite set of moment constraints. We show that the calibration algorithm is stable (in the Prokhorov metric) under a perturbation of the prior and the calibrated distributions converge in variation to the measure from which the moments have been taken as more constraints are added. These facts are used to explain the limiting properties of the minimum relative entropy Monte Carlo calibration algorithm.

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Ye, Heng-Qing, et David D. Yao. « Diffusion Approximation for Fair Resource Control—Interchange of Limits Under a Moment Condition ». Mathematics of Operations Research 46, n^o 3 (août 2021) : 869–94. http://dx.doi.org/10.1287/moor.2020.1065.

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In a prior study [Ye HQ, Yao DD (2016) Diffusion limit of fair resource control–Stationary and interchange of limits. Math. Oper. Res. 41(4):1161–1207.] focusing on a class of stochastic processing network with fair resource control, we justified the diffusion approximation (in the context of the interchange of limits) provided that the pth moment of the workloads are bounded. To this end, we introduced the so-called bounded workload condition, which requires the workload process be bounded by a free process plus the initial workload. This condition is for a derived process, the workload, as opposed to primitives such as arrival processes and service requirements; as such, it could be difficult to verify. In this paper, we establish the interchange of limits under a moment condition of suitable order on the primitives directly: the required order is [Formula: see text] on the moments of the primitive processes so as to bound the pth moment of the workload. This moment condition is trivial to verify, and indeed automatically holds in networks where the primitives have moments of all orders, for instance, renewal arrivals with phase-type interarrival times and independent and identically distributed phase-type service times.

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Zanardo, Alberto. « Branching-time logic with quantification over branches : The point of view of modal logic ». Journal of Symbolic Logic 61, n^o 1 (mars 1996) : 1–39. http://dx.doi.org/10.2307/2275595.

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AbstractIn Ockhamist branching-time logic [Prior 67], formulas are meant to be evaluated on a specified branch, or history, passing through the moment at hand. The linguistic counterpart of the manifoldness of future is a possibility operator which is read as ‘at some branch, or history (passing through the moment at hand)’. Both the bundled-trees semantics [Burgess 79] and the 〈moment, history〉 semantics [Thomason 84] for the possibility operator involve a quantification over sets of moments. The Ockhamist frames are (3-modal) Kripke structures in which this second-order quantification is represented by a first-order quantification. The aim of the present paper is to investigate the notions of modal definability, validity, and axiomatizability concerning 3-modal frames which can be viewed as generalizations of Ockhamist frames.

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Tran, Thi-Thao, Van-Truong Pham et Kuo-Kai Shyu. « Moment-based alignment for shape prior with variational B-spline level set ». Machine Vision and Applications 24, n^o 5 (14 avril 2013) : 1075–91. http://dx.doi.org/10.1007/s00138-013-0504-2.

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Smith, Richard S., et Terry J. Lee. « The moments of the impulse response : A new paradigm for the interpretation of transient electromagnetic data ». GEOPHYSICS 67, n^o 4 (juillet 2002) : 1095–103. http://dx.doi.org/10.1190/1.1500370.

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We define the nth moment of the transient electromagnetic impulse response as the definite integral with respect to time of the “quadrature” magnetic‐field impulse response weighted by time to the nth power. In this context, the quadrature response is defined as the full impulse response with the in‐phase component (i.e., the delta function component at zero time) removed. The low‐order moments are equivalent to familiar quantities: the zeroth moment (n = 0) is numerically equal to the frequency‐domain inductive limit, and the first moment is the resistive‐limit response. The higher order moments can be of particular benefit: successively they put greater emphasis on the late‐time data, and hence can bring out features in the data that are more conductive or deeper. An advantage of calculating moments (and hence the inductive and resistive limit) is that these data are not strongly dependent on any distortion of the waveform from an ideal impulse. Hence, it is not critical to deconvolve the data prior to estimating the moments. If a conductor has a single exponential decay, the nth moment of the decay is proportional to the nth power of the time constant of the exponential. Thus, it is relatively easy to estimate the time constant from the moments. For a conductive sphere model, the expressions for the moments are more complicated, but are still simpler than the full transient solution or the frequency‐domain solution. In a field example, the high‐order moments emphasize local highly conductive features, but also show the noise present in the late‐time data. A discrete feature on the profile evident in moments 3 through 10 has been modeled as a spherical conductor with its center at 90 m depth, a radius of 45 m, and a conductivity of 9.4 S/m.

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Darvish, Shahrzad E., Jean-Sebastien Rachoin, Dennis Meredith, Denise Polat, Jessica McKnight, Jes Smith, Tracey Hamilton et Raquel Nahra. « 983. Hand Hygiene not only the Motion but the Moments ». Open Forum Infectious Diseases 7, Supplement_1 (1 octobre 2020) : S519—S520. http://dx.doi.org/10.1093/ofid/ofaa439.1169.

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Abstract Background Hand hygiene (HH) is a paradigm of infection prevention.Often emphasis has been placed on appropriate motion of hand hygiene.The implementation of the 5 moments of HH in clinical practice hindered by the perceived enormous lift of educating healthcare providers. Hand Hygiene Moments Opportunities Methods Retrospective evaluation of education on WHO 5 moments of HH implementation. Other data collected CLABSI, CAUTI, MDR Acinetobacter, MRSA, Clostridium difficile LabID. Education occurred between October and December 2018. Data was collected from January 2018 to December 2019. Baseline 5 Moments of HH was obtained for 3 weeks prior to education as this was newly introduced. Statistical analyses using control charts with testing for special cause variations included all data point before and after education of 5 moments of HH. We used Pearson correlation to assess relation between HAI and HH. 5 moments of HH education was done through direct observation with feedback, traditional lecturing, and computer-based education mandatory to all employees and posters placed in strategic locations through the institution. Determination of patient and hospital zone allowed to streamline the education process. Education on different moments was individualized for each discipline in accordance to its involvement with patients. Zones by Lay Out Patient Zone and Hospital Zone Results Education increased HH compliance over the 12 months period post intervention. The number of observations per moment per month ranged between 96 and 351 observations most observation opportunities during moment 1 (M1) and 5 (M5). M1 correlated positively significantly with moment 2 (M2) (P=0.001) moment 3 (M3) (p < 0.001) moment 4 (M4) (p =0,001) but not moment 5 (M5) M2 correlated positively with M3 (p < 0.001), M4 (p< 0.001) Not M5. M3 correlated positively with M4(p< 0.001) Not M5 No Correlations between CLABSI, CAUTI, CDI, MRSA and M1-M5 or Hand Hygiene. There is a correlation between the decrease in MDR Acinetobacter incidence and point prevalence and compliance with M1 (p 0.04), M2 (p < 0.001), M3 (p 0.002) and M4 (p 0.028). Conclusion Education of 5 moments of HH in a combined effort between infection prevention and front-line staff to identify patient and hospital zone showed an increased adherence to Hand hygiene overtime. Compliance with M 1 was associated with increased compliance with M2, M3 and M4. Disclosures Raquel Nahra, MD, Medline sponsored the study (Other Financial or Material Support, Supported financially and provided material)

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Hyde, Milo W. « Independently Controlling Stochastic Field Realization Magnitude and Phase Statistics for the Construction of Novel Partially Coherent Sources ». Photonics 8, n^o 2 (22 février 2021) : 60. http://dx.doi.org/10.3390/photonics8020060.

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In this paper, we present a method to independently control the field and irradiance statistics of a partially coherent beam. Prior techniques focus on generating optical field realizations whose ensemble-averaged autocorrelation matches a specified second-order field moment known as the cross-spectral density (CSD) function. Since optical field realizations are assumed to obey Gaussian statistics, these methods do not consider the irradiance moments, as they, by the Gaussian moment theorem, are completely determined by the field’s first and second moments. Our work, by including control over the irradiance statistics (in addition to the CSD function), expands existing synthesis approaches and allows for the design, modeling, and simulation of new partially coherent beams, whose underlying field realizations are not Gaussian distributed. We start with our model for a random optical field realization and then derive expressions relating the ensemble moments of our fields to those of the desired partially coherent beam. We describe in detail how to generate random optical field realizations with the proper statistics. We lastly generate two example partially coherent beams using our method and compare the simulated field and irradiance moments theory to validate our technique.

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Harcourt, Ramsey R. « An Improved Second-Moment Closure Model of Langmuir Turbulence ». Journal of Physical Oceanography 45, n^o 1 (janvier 2015) : 84–103. http://dx.doi.org/10.1175/jpo-d-14-0046.1.

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AbstractA prior second-moment closure (SMC) model of Langmuir turbulence in the upper ocean is modified by introduction of inhomogeneous pressure–strain rate and pressure–scalar gradient closures that are similar to the high Reynolds number, near-wall treatments for solid wall boundaries. This repairs several near-surface defects in the algebraic Reynolds stress model (ARSM) of the prior SMC by redirecting Craik–Leibovich (CL) vortex force production of turbulent kinetic energy out of the surface-normal vertical component and into a horizontal one, with an associated reduction in near-surface CL production of vertical momentum flux. A surface-proximity function introduces a new closure parameter that is tuned to previous results from large-eddy simulations (LES), and a numerical SMC model based on stability functions from the new ARSM produces improved comparisons with mean profiles of momentum and TKE components from steady-state LES results forced by aligned wind and waves. An examination of higher-order quasi-homogeneous closures and a numerical simulation of Langmuir turbulence away from the boundaries both show the near-surface inhomogeneous closure to be both necessary for consistency and preferable for simplicity.

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Field, Paul R., Andrew J. Heymsfield et Aaron Bansemer. « Snow Size Distribution Parameterization for Midlatitude and Tropical Ice Clouds ». Journal of the Atmospheric Sciences 64, n^o 12 (1 décembre 2007) : 4346–65. http://dx.doi.org/10.1175/2007jas2344.1.

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Abstract Many microphysical process rates involving snow are proportional to moments of the snow particle size distribution (PSD), and in this study a moment estimation parameterization applicable to both midlatitude and tropical ice clouds is proposed. To this end aircraft snow PSD data were analyzed from tropical anvils [Tropical Rainfall Measuring Mission/Kwajelein Experiment (TRMM/KWAJEX), Cirrus Regional Study of Tropical Anvils and Cirrus Layers-Florida Area Cirrus Experiment (CRYSTAL-FACE)] and midlatitude stratiform cloud [First International Satellite Cloud Climatology Project Research Experiment (FIRE), Atmospheric Radiation Measurement Program (ARM)]. For half of the dataset, moments of the PSDs are computed and a parameterization is generated for estimating other PSD moments when the second moment (proportional to the ice water content when particle mass is proportional to size squared) and temperature are known. Subsequently the parameterization was tested with the other half of the dataset to facilitate an independent comparison. The parameterization for estimating moments can be applied to midlatitude or tropical clouds without requiring prior knowledge of the regime of interest. Rescaling of the tropical and midlatitude size distributions is presented along with fits to allow the user to recreate realistic PSDs given estimates of ice water content and temperature. The effects of using different time averaging were investigated and were found not to be adverse. Finally, the merits of a single-moment snow microphysics versus multimoment representations are discussed, and speculation on the physical differences between the rescaled size distributions from the Tropics and midlatitudes is presented.

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Le Blanc, Richard. « Jaynes-Gibbs Entropic Convex Duals and Orthogonal Polynomials ». Entropy 24, n^o 5 (16 mai 2022) : 709. http://dx.doi.org/10.3390/e24050709.

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The univariate noncentral distributions can be derived by multiplying their central distributions with translation factors. When constructed in terms of translated uniform distributions on unit radius hyperspheres, these translation factors become generating functions for classical families of orthogonal polynomials. The ultraspherical noncentral t, normal N, F, and χ2 distributions are thus found to be associated with the Gegenbauer, Hermite, Jacobi, and Laguerre polynomial families, respectively, with the corresponding central distributions standing for the polynomial family-defining weights. Obtained through an unconstrained minimization of the Gibbs potential, Jaynes’ maximal entropy priors are formally expressed in terms of the empirical densities’ entropic convex duals. Expanding these duals on orthogonal polynomial bases allows for the expedient determination of the Jaynes–Gibbs priors. Invoking the moment problem and the duality principle, modelization can be reduced to the direct determination of the prior moments in parametric space in terms of the Bayes factor’s orthogonal polynomial expansion coefficients in random variable space. Genomics and geophysics examples are provided.

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Chung, Kyu-soo, Dong Soo Ryu et Seunghwan Lee. « The effects of prior affect and sensory stimuli on motorsport spectators’ in-the-moment experiences ». International Journal of Sports Marketing and Sponsorship 17, n^o 4 (7 novembre 2016) : 302–19. http://dx.doi.org/10.1108/ijsms-11-2016-020.

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Purpose The purpose of this paper is to provide meaningful information to sport organizations that have just recently started hosting sporting events in a new market and want to build long-term relationships with that market’s consumers. Design/methodology/approach Using self-administered questionnaires, the study surveys 463 spectators who attended the 2012 Formula One Korean Grand Prix. Findings Prior affect and existing sensory cues are crucial for spectators’ consumption behavior. Spectators’ prior event attendance plays a significant role on perceiving sensory stimuli as well as on consequent outcomes. This study also finds arousal significantly affected by seeing and hearing and prior affect. Arousal mediates the effects of these sensory stimuli and prior affect on satisfaction and revisit intention. Originality/value This study expands the knowledge on spectators’ experience at live sporting events. In addition, more dimensions of the mechanisms that are at work between cognitive elements and sensory stimuli are added to the existing knowledge of sport spectators’ behavior.

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Won Hyo Yoon et Soon Heung Chang. « Systematic Bayes prior-assignment by coupling the mini-max entropy and moment-matching methods ». IEEE Transactions on Reliability 43, n^o 2 (juin 1994) : 279–87. http://dx.doi.org/10.1109/24.295011.

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Chae, Seungheon, Ahnryul Choi, Hyunwoo Jung, Tae Hyong Kim, Kyungran Kim et Joung Hwan Mun. « Machine Learning Model to Estimate Net Joint Moments during Lifting Task Using Wearable Sensors : A Preliminary Study for Design of Exoskeleton Control System ». Applied Sciences 11, n^o 24 (10 décembre 2021) : 11735. http://dx.doi.org/10.3390/app112411735.

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Accurately measuring the lower extremities and L5/S1 moments is important since L5/S1 moments are the principal parameters that measure the risk of musculoskeletal diseases during lifting. In this study, protocol that predicts lower extremities and L5/S1 moments with an insole sensor was proposed to replace the prior methods that have spatial constraints. The protocol is hierarchically composed of a classification model and a regression model to predict joint moments. Additionally, a single LSTM model was developed to compare with proposed protocol. To optimize hyperparameters of the machine learning model and input feature, Bayesian optimization method was adopted. As a result, the proposed protocol showed a relative root mean square error (rRMSE) of 8.06~13.88% while the single LSTM showed 9.30~18.66% rRMSE. This protocol in this research is expected to be a starting point for developing a system for estimating the lower extremity and L5/S1 moment during lifting that can replace the complex prior method and adopted to workplace environments. This novel study has the potential to precisely design a feedback iterative control system of an exoskeleton for the appropriate generation of an actuator torque.

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Zhang, Yan Hua, Hua Xing Li, Deng Cheng Zhang et Liang Qu. « The Effect of Nose Bluntness and Forebody Strakes on Aerodynamic Characteristics of Air-Launched Rocket Model ». Applied Mechanics and Materials 391 (septembre 2013) : 143–49. http://dx.doi.org/10.4028/www.scientific.net/amm.391.143.

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In this paper, the aerodynamic characteristics of the rocket model that might be used in a cabin air-launched system have been studied through experiments in low speed wind tunnel. The angle of incidence range is 0-80°, and the speed is 17m/s or 25m/s, including typical flight conditions prior to engine ignition. Forces and moments were measured through six-component balance. It is found that vortex asymmetry appears under certain condition with zero side slip. Asymmetrical phenomenon leads to larger side force and yaw moment, which can affect the trajectory of the rocket and put the carrier aircraft at risk. In addition, changes in regulation of the pitching moment with angle of attack are important to longitudinal stability, so the model with convergent-expanded afterbody was designed to improve stability. The effects of nose bluntness and forebody strakes on side force and yaw moment were presented, and the differences of aerodynamic characteristics with pointed and blunt nose, with and without forebody strakes were described. Results show that nose bluntness delays the appearance of asymmetric vortex, and the maximum side force is reduced by at least 50%. The forebody strakes reduce side force and yaw moment by weakening the asymmetric vortical interactions. The results can provide some references for designing the cabin air-launched rocket.

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Lavender, Steven A., William S. Marras, Sue A. Ferguson, Riley E. Splittstoesser, Gang Yang et Pete Schabo. « Identifying Safe Load Moment Exposures for the Back ». Proceedings of the Human Factors and Ergonomics Society Annual Meeting 53, n^o 14 (octobre 2009) : 883. http://dx.doi.org/10.1177/154193120905301405.

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Low back disorders continue to be the most common and significant work-related musculoskeletal disorders in the US. Identifying what constitutes a “safe” physical workload has been the biggest challenge facing injury prevention efforts. Prior low back injury risk models have focused on manufacturing activities where there is limited variability in the parameters used to describe the exposures to low back disorder risk factors. Lifting tasks in distribution centers can have considerably more variability in load and physical layout. The goal of this project was to identify and quantify measures that characterize the biomechanical risk factors, including measures of the load moment exposure, and measures that characterize the duty cycle that are predictive of low back disorders in distribution centers. Thus, our hypothesis was that we could define a relationship between moment exposure parameters and the low back disorder incidence rates. A cross-sectional study was designed to examine the mechanical risk factors responsible for reported low back injury in distributions centers. The physical exposure was measured on 195 workers on 50 jobs in 21 distribution centers using a sonic-based Moment Exposure Tracking System (METS). The METS measures load, force, load moment, torso kinematics, and temporal parameters of the job simultaneously. For each job, low back injury rates were collected retrospectively from the company's records over the prior 3-year period. The data were used to develop a risk model designed to predict back injury risk based upon direct measures of load and load moment exposure. The model incorporates biomechanical variables which include the load moment and horizontal sliding forces, as well as a temporal variable indicating the opportunity for micro-breaks during the work process. Overall, the presented model has very good sensitivity (87%) and specificity (73%).

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Andrade Borges, Emilia, Eva O. L. Lantsoght, Sebastián Castellanos-Toro et Johannio Marulanda Casas. « Modeling and analysis of a prestressed girder bridge prior to diagnostic load testing ». ACI Avances en Ciencias e Ingenierías 13, n^o 2 (22 novembre 2021) : 23. http://dx.doi.org/10.18272/aci.v13i2.2295.

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Progressive deterioration is a problem that affects road infrastructure, especially bridges. This requires the development of methods for its adequate detection and revision, one of them being load testing. Within load testing, finite element analysis (FEA) models provide initial information to understand the behavior of a structure and plan accordingly, which represents a fundamental step towards a precise structural evaluation of a bridge. This study focused on the modeling and analysis of the static response of the bridge over the river Lili in Cali, Colombia, a prestressed girder bridge programmed to undergo a diagnostic load test. A linear FEA model was created with information from a manual survey and from other bridges’ plans designed and built under the regulations in force at the time. Due to the absence of plans and design specifications for the bridge, variations were applied to certain model parameters (stiffness of diaphragms and elastomeric bearings), to quantify their effect on the overall behavior of the bridge. The analysis included obtaining the critical position for the design vehicles, the transversal distribution of stresses and determining the influence of the variation parameters in the response of the structure. Results showed that the critical combinations for bending moment and shear were when the loads were the closest to the exterior girders, being these elements the most affected. The variation on the modulus of elasticity for the diaphragms and the stiffness of the elastomeric bearings did not significantly influence the results for bending moment and shear, nor the critical position. Girder distribution factors (GDF) from the model were compared to previous research, finding similarities in shape and value with other FEA models and experimental results. Finally, an instrumentation plan focused on the girders of the bridge was proposed based on the zones where the maximum effects are expected. The findings in this study show how linear FEA models provide initial but relevant information regarding the critical position of design vehicles, the distribution of stresses and the expected values for bending moment and shear under design loads.

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Boudreau, Carmen, Peter D. MacIntyre et Jean-Marc Dewaele. « Enjoyment and anxiety in second language communication : An idiodynamic approach ». Studies in Second Language Learning and Teaching 8, n^o 1 (27 mars 2018) : 149–70. http://dx.doi.org/10.14746/ssllt.2018.8.1.7.

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Emotions are a fleeting experience, sometimes lasting only moments before dissipating. Prior research in SLA has either ignored emotions, underestimated their relevance, or has studied them as a relatively stable individual difference variable. In contrast, the present study takes an idiodynamic approach to examine the rapidly changing relationship between enjoyment and anxiety in second language communication, on a moment-to-moment timescale. University students who speak French as a second language were recruited to complete oral tasks in their second language. Participants then rated their per-second fluctuations in each emotion while watching a video recording of their tasks. Immediately after this, they were interviewed about their attributions for fluctuations in their ratings. We found that the relationship between enjoyment and anxiety is highly dynamic, resulting in varying patterns of correlation ranging from negative to positive. Triangulation of ratings of anxiety and enjoyment with interview data produces a richer understanding of the role of emotions in second language communication.

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Montoli, A., M. Antonelli, F. Magistrelli et P. M. Pizzochero. « Bayesian estimate of the superfluid moments of inertia from the 2016 glitch in the Vela pulsar ». Astronomy & ; Astrophysics 642 (octobre 2020) : A223. http://dx.doi.org/10.1051/0004-6361/202038340.

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Context. The observation of the first pulse-to-pulse glitch in the Vela pulsar opens a new window among theoretical speculations on the internal dynamics of neutron stars as it allows us for testing models to factor in the circumstances of the first moments of a glitch. Several works in the literature have already considered the observational and physical parameters of the star by employing a minimal model with three rigidly rotating components. Aims. We improve the analytical study of the minimal three-component model for pulsar glitches by solving it with generic initial conditions for the two initial lags of their superfluid components. The purpose is to use this solution to fit the data of the 2016 Vela glitch by employing a Bayesian approach and to obtain a probability distribution for the physical parameters of the model and for observational parameters, such as the glitch rise time and the relaxation timescale. Methods. The fit is achieved through Bayesian inference. Due to the presence of an increase in the timing residuals near the glitch time, an extra magnetospheric component was added to the three-component model to deal with this phenomenon. A physically reasonable, non-informative prior was set on the different parameters of the model, so that the posterior distribution could be compared with state-of-the-art information obtained from microphysical calculations. By considering a model with a tightened prior on the moment of inertia fractions and by comparing it with the original model by means of Bayesian model selection, we studied the possibility of a crust-limited superfluid reservoir. Results. We obtained the posterior distribution for the moment of inertia fractions of the superfluid components, the coupling parameters, and the initial velocity lags between the components. An analysis of the inferred posterior also confirmed the presence of an overshoot in that glitch and set an upper limit of ∼6 s on the glitch rise timescale. The comparison between the two models with different priors on the moment of inertia fractions appears to indicate a need for a core participation in the glitch phenomenon, regardless of the uncertain strength of the entrainment coupling.

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Shao, Yuanjie, Nong Sang, Juncai Peng et Changxin Gao. « Joint Image Deblurring and Matching with Blurred Invariant-Based Sparse Representation Prior ». Complexity 2019 (31 octobre 2019) : 1–12. http://dx.doi.org/10.1155/2019/3829263.

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Image matching is important for vision-based navigation. However, most image matching approaches do not consider the degradation of the real world, such as image blur; thus, the performance of image matching often decreases greatly. Recent methods try to deal with this problem by utilizing a two-stage framework—first resorting to image deblurring and then performing image matching, which is effective but depends heavily on the quality of image deblurring. An emerging way to resolve this dilemma is to perform image deblurring and matching jointly, which utilize sparse representation prior to explore the correlation between deblurring and matching. However, these approaches obtain the sparse representation prior in the original pixel space, which do not adequately consider the influence of image blurring and thus may lead to an inaccurate estimation of sparse representation prior. Fortunately, we can extract the pseudo-Zernike moment with blurred invariant from images and obtain a reliable sparse representation prior in the blurred invariant space. Motivated by the observation, we propose a joint image deblurring and matching method with blurred invariant-based sparse representation prior (JDM-BISR), which obtains the sparse representation prior in the robust blurred invariant space rather than the original pixel space and thus can effectively improve the quality of image deblurring and the accuracy of image matching. Moreover, since the dimension of the pseudo-Zernike moment is much lower than the original image feature, our model can also increase the computational efficiency. Extensive experimental results demonstrate that the proposed method performs favorably against the state-of-the-art blurred image matching approach.

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Yahia, Eman, William Schupbach et Kannan N. Premnath. « Three-Dimensional Central Moment Lattice Boltzmann Method on a Cuboid Lattice for Anisotropic and Inhomogeneous Flows ». Fluids 6, n^o 9 (10 septembre 2021) : 326. http://dx.doi.org/10.3390/fluids6090326.

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Lattice Boltzmann (LB) methods are usually developed on cubic lattices that discretize the configuration space using uniform grids. For efficient computations of anisotropic and inhomogeneous flows, it would be beneficial to develop LB algorithms involving the collision-and-stream steps based on orthorhombic cuboid lattices. We present a new 3D central moment LB scheme based on a cuboid D3Q27 lattice. This scheme involves two free parameters representing the ratios of the characteristic particle speeds along the two directions with respect to those in the remaining direction, and these parameters are referred to as the grid aspect ratios. Unlike the existing LB schemes for cuboid lattices, which are based on orthogonalized raw moments, we construct the collision step based on the relaxation of central moments and avoid the orthogonalization of moment basis, which leads to a more robust formulation. Moreover, prior cuboid LB algorithms prescribe the mappings between the distribution functions and raw moments before and after collision by using a moment basis designed to separate the trace of the second order moments (related to bulk viscosity) from its other components (related to shear viscosity), which lead to cumbersome relations for the transformations. By contrast, in our approach, the bulk and shear viscosity effects associated with the viscous stress tensor are naturally segregated only within the collision step and not for such mappings, while the grid aspect ratios are introduced via simpler pre- and post-collision diagonal scaling matrices in the above mappings. These lead to a compact approach, which can be interpreted based on special matrices. It also results in a modular 3D LB scheme on the cuboid lattice, which allows the existing cubic lattice implementations to be readily extended to those based on the more general cuboid lattices. To maintain the isotropy of the viscous stress tensor of the 3D Navier–Stokes equations using the cuboid lattice, corrections for eliminating the truncation errors resulting from the grid anisotropy as well as those from the aliasing effects are derived using a Chapman–Enskog analysis. Such local corrections, which involve the diagonal components of the velocity gradient tensor and are parameterized by two grid aspect ratios, augment the second order moment equilibria in the collision step. We present a numerical study validating the accuracy of our approach for various benchmark problems at different grid aspect ratios. In addition, we show that our 3D cuboid central moment LB method is numerically more robust than its corresponding raw moment formulation. Finally, we demonstrate the effectiveness of the 3D cuboid central moment LB scheme for the simulations of anisotropic and inhomogeneous flows and show significant savings in memory storage and computational cost when used in lieu of that based on the cubic lattice.

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Cameron, Brenda L. « Ethical Moments in Practice : the nursing ‘how are you?’ revisited ». Nursing Ethics 11, n^o 1 (janvier 2004) : 53–62. http://dx.doi.org/10.1191/0969733004ne666oa.

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In seeking for an understanding of ethical practices in health care situations, our challenge is always both to recognize and respond to the call of individuals in need. In attuning ourselves to the call of the vulnerable other an ethical moment arises. Asking ‘how are you?’ in health care practice is our very first possibility to learn how a particular person finds herself or himself in this particular situation. Here, ‘how are you?’ shows itself as an ethical question that opens up a relational space that calls forth a response. It is a way to understand the situated moments in which we are already that enables us to act respectfully. Our ethical frameworks assist us in trying to decide what is the right thing to do given a set of circumstances. Yet there is a prior step that already calls us to ethical attention; this is when we ask ‘how are you?’, which transforms a seemingly small interaction into an ethical moment. ‘How are you?’ is a question that turns us back to who we are as health care professionals and calls us to be more deeply attentive to the moment. When we sincerely ask ‘how are you?’ we enact our ethical commitments to one another.

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Meng, Ting, Richard Carew, Wojciech J. Florkowski et Anna M. Klepacka. « Analyzing Temperature and Precipitation Influences on Yield Distributions of Canola and Spring Wheat in Saskatchewan ». Journal of Applied Meteorology and Climatology 56, n^o 4 (avril 2017) : 897–913. http://dx.doi.org/10.1175/jamc-d-16-0258.1.

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AbstractThe IPCC indicates that global mean temperature increases of 2°C or more above preindustrial levels negatively affect such crops as wheat. Canadian climate model projections show warmer temperatures and variable rainfall will likely affect Saskatchewan’s canola and spring wheat production. Drier weather will have the greatest impact. The major climate change challenges will be summer water availability, greater drought frequencies, and crop adaptation. This study investigates the impact of precipitation and temperature changes on canola and spring wheat yield distributions using Environment Canada weather data and Statistics Canada crop yield and planted area for 20 crop districts over the 1987–2010 period. The moment-based methods (full- and partial-moment-based approaches) are employed to characterize and estimate asymmetric relationships between climate variables and the higher-order moments of crop yields. A stochastic production function and the focus on crop yield’s elasticity imply choosing the natural logarithm function as the mean function transformation prior to higher-moment function estimation. Results show that average crop yields are positively associated with the growing season degree-days and pregrowing season precipitation, while they are negatively affected by extremely high temperatures in the growing season. The climate measures have asymmetric effects on the higher moments of crop yield distribution along with stronger effects of changing temperatures than precipitation on yield distribution. Higher temperatures tend to decrease wheat yields, confirming earlier Saskatchewan studies. This study finds pregrowing season precipitation and precipitation in the early plant growth stages particularly relevant in providing opportunities to develop new crop varieties and agronomic practices to mitigate climate changes.

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Ferreira, Johannes T., Tanita Botha et Andriette Bekker. « Tsallis and Other Generalised Entropy Forms Subject to Dirichlet Mixture Priors ». Symmetry 14, n^o 6 (28 mai 2022) : 1110. http://dx.doi.org/10.3390/sym14061110.

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Entropy indicates a measure of information contained in a complex system, and its estimation continues to receive ongoing focus in the case of multivariate data, particularly that on the unit simplex. Oftentimes the Dirichlet distribution is employed as choice of prior in a Bayesian framework conjugate to the popular multinomial likelihood with K distinct classes, where consideration of Shannon- and Tsallis entropy is of interest for insight detection within the data on the simplex. However, this prior choice only accounts for negatively correlated data, therefore this paper incorporates previously unconsidered mixtures of Dirichlet distributions as potential priors for the multinomial likelihood which addresses the drawback of negative correlation. The power sum functional, as the product moment of the mixture of Dirichlet distributions, is of direct interest in the multivariate case to conveniently access the Tsallis- and other generalized entropies that is incorporated within an estimation perspective of the posterior distribution using real economic data. A prior selection method is implemented to suggest a suitable prior for the consideration of the practitioner; empowering the user in future for consideration of suitable priors incorporating entropy within the estimation environment as well as having the option of certain mixture of Dirichlet distributions that may require positive correlation.

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Sun, Zhen Hui, Lan Li Chen et Zhi Hua Xiong. « Magnetism Driven by Intrinsic Defect in GaN Nanowires ». Advanced Materials Research 236-238 (mai 2011) : 2160–65. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.2160.

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We have investigated the magnetic properties, the electronic structure, and the formation energy of wurtzite GaN nanowires (NWs) with gallium vacancies by using the density-functional theory. The NW has been constructed along the [0001] direction. It was found that Ga vacancies prior to reside on the NW surface due to the lower formation energy. Interestingly, it was found that the GaN NWs with a Ga vacancy can show induced local magnetic moment in N atoms, with a magnetic moment about 0.60 uB. The study of vacancy-vacancy interactions indicates that the NWs prefer ferromagnetic ground state. We further confirmed that the total magnetic moments can be increased by increasing the Ga vacancy concentration without significant energy cost. The theoretical results are in good agreement with the recent experimental observations. Our findings are helpful to gain a more novel understanding of structural and spin properties of Ga vacancy in wurtzite GaN NWs, and also provide a possible way to generate the low dimensional magnetic GaN nanostructures by introducing Ga vacancies instead of doping with transition-metal atoms.

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Kyprianou, A. E., et Z. Palmowski. « Distributional Study of De Finetti's Dividend Problem for a General Lévy Insurance Risk Process ». Journal of Applied Probability 44, n^o 2 (juin 2007) : 428–43. http://dx.doi.org/10.1239/jap/1183667412.

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We provide a distributional study of the solution to the classical control problem due to De Finetti (1957), Gerber (1969), Azcue and Muler (2005), and Avram et al. (2007), which concerns the optimal payment of dividends from an insurance risk process prior to ruin. Specifically, we build on recent work in the actuarial literature concerning calculations of the nth moment of the net present value of dividends paid out in the optimal strategy as well as the moments of the deficit at ruin and the Laplace transform of the red period. The calculations we present go much further than the existing literature, in that our calculations are valid for a general spectrally negative Lévy process as opposed to the classical Cramér–Lundberg process with exponentially distributed jumps. Moreover, the technique we use appeals principally to excursion theory rather than integro-differential equations and, for the case of the nth moment of the net present value of dividends, makes a new link with the distribution of integrated exponential subordinators.

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Kyprianou, A. E., et Z. Palmowski. « Distributional Study of De Finetti's Dividend Problem for a General Lévy Insurance Risk Process ». Journal of Applied Probability 44, n^o 02 (juin 2007) : 428–43. http://dx.doi.org/10.1017/s0021900200117930.

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We provide a distributional study of the solution to the classical control problem due to De Finetti (1957), Gerber (1969), Azcue and Muler (2005), and Avram et al. (2007), which concerns the optimal payment of dividends from an insurance risk process prior to ruin. Specifically, we build on recent work in the actuarial literature concerning calculations of the nth moment of the net present value of dividends paid out in the optimal strategy as well as the moments of the deficit at ruin and the Laplace transform of the red period. The calculations we present go much further than the existing literature, in that our calculations are valid for a general spectrally negative Lévy process as opposed to the classical Cramér–Lundberg process with exponentially distributed jumps. Moreover, the technique we use appeals principally to excursion theory rather than integro-differential equations and, for the case of the nth moment of the net present value of dividends, makes a new link with the distribution of integrated exponential subordinators.

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Kyprianou, A. E., et Z. Palmowski. « Distributional Study of De Finetti's Dividend Problem for a General Lévy Insurance Risk Process ». Journal of Applied Probability 44, n^o 02 (juin 2007) : 428–43. http://dx.doi.org/10.1017/s0021900200003077.

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We provide a distributional study of the solution to the classical control problem due to De Finetti (1957), Gerber (1969), Azcue and Muler (2005), and Avram et al. (2007), which concerns the optimal payment of dividends from an insurance risk process prior to ruin. Specifically, we build on recent work in the actuarial literature concerning calculations of the nth moment of the net present value of dividends paid out in the optimal strategy as well as the moments of the deficit at ruin and the Laplace transform of the red period. The calculations we present go much further than the existing literature, in that our calculations are valid for a general spectrally negative Lévy process as opposed to the classical Cramér–Lundberg process with exponentially distributed jumps. Moreover, the technique we use appeals principally to excursion theory rather than integro-differential equations and, for the case of the nth moment of the net present value of dividends, makes a new link with the distribution of integrated exponential subordinators.

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Lewis, W. J. « Mathematical model of a moment-less arch ». Proceedings of the Royal Society A : Mathematical, Physical and Engineering Sciences 472, n^o 2190 (juin 2016) : 20160019. http://dx.doi.org/10.1098/rspa.2016.0019.

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This paper presents a mathematical model for predicting the geometrical shapes of rigid, two-pin, moment-less arches of constant cross section. The advancement of this work lies in the inclusion of arch self-weight and the ability to produce moment-less arch forms for any span/rise ratio, and any ratio of uniformly distributed load per unit span, w , to uniformly distributed arch weight per unit arch length, q . The model is used to derive the shapes of two classical ‘moment-less’ arch forms: parabolic and catenary, prior to demonstrating a general case, not restricted by the unrealistic load assumptions (absence of q , in the case of a parabolic form, or no w , in the case of a catenary arch). Using the same value of span/rise ratio, and w / q >1, the behaviour of the moment-less and parabolic arches under permanent loading, ( w + q ), is analysed. Results show the former to be developing much lower stresses than its parabolic rival, even when there are relatively small differences in the two geometries; for a medium span/rise ratio of 4 and w / q =2, differences in the parabolic and moment-less arch geometries would, in practical terms, be viewed as insignificant, but the stresses in them are different.

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GORDON, CYNTHIA. « “I'm Mommy and you're Natalie” : Role-reversal and embedded frames in mother-child discourse ». Language in Society 31, n^o 5 (novembre 2002) : 679–720. http://dx.doi.org/10.1017/s004740450231501x.

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This study investigates framing in discourse while considering spontaneous role-play between a young child (age 2 years 11 months) and her mother, wherein the participants reverse roles from real life and reenact shared prior experiences. Data consist of two tape-recorded naturally occurring pretend-play episodes and the real-life interactions on which they are based, all of which took place at home. Analysis of the role-play episodes illustrates how framing occurs from moment to moment in interaction in this context, showing that the participants use both play and non-play utterances collaboratively to evoke, maintain, and embed multiple play frames with increasingly specific, and at times blended, metamessages. By linking the role-play interactions back to their real-life counterparts, I explore the relationship between framing and “prior text.” This analysis adds to our understanding of framing by showing how frames are layered in discourse. Additionally, it links frames theory to the notion of intertextuality by illustrating how prior text can be used as a resource for framing.

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Tayara, O., L. Zapała, M. Lipa et A. Antoniewicz. « Pentafecta : The more fair self-assessment at the moment of patients' consultation prior to radical prostatectomy ». European Urology Supplements 14, n^o 6 (octobre 2015) : e1202. http://dx.doi.org/10.1016/s1569-9056(15)30238-4.

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Campi, Emidio. « Commemorating the Quincentenary of the Reformation ». Journal of the Council for Research on Religion 1, n^o 2 (28 août 2020) : 1–19. http://dx.doi.org/10.26443/jcreor.v1i2.23.

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To commemorate the 500th anniversary of the start of the Protestant Reformation this article will offer a brief historical overview of the key figures and events which demonstrate that the Reformation was not born out of a single moment, but is a movement that developed prior to Martin Luther’s Nintey-Five Theses in protest of the Roman Catholic Church. A movement which grew out of the early Church and Middles Ages and continued to impact the history of Christianity well into the twentieth century. Moving from the early Church to modern history this article will examine the interpretation of the reformatio ecclesiae as well as its usage and meaning at specific historical moments and by specific reformers.

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Aquino, Marcos Aurelio Gomes de, Carlos Eduardo Cavalcante, Patrícia Trindade Caldas et Josiete Da Silva Mendes. « In search of retention : volunteers in a Brazilian NGO ». Revista de Administração da UFSM 13, n^o 1 (29 mars 2020) : 144. http://dx.doi.org/10.5902/1983465924970.

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This study aims to analyse the motives that lead current and prospective volunteers to engage in volunteer activity at the Cidade Viva Foundation in the city of João Pessoa, state of Paraíba, Brazil. To that end, the model proposed by Cavalcante (2016) is employed to describe volunteers’ motivational profiles at different points in time: their prior expectations, at the moment when they join the organization, and when they quit. The methodology chosen includes descriptive research and analysis of data collected through questionnaire-based interviews with volunteers at the Cidade Viva Foundation using inferential statistics (Student’s t test and Bonferroni test -ANOVA). Among the most significant findings is the predominance of the altruistic profile, followed by the social justice profile, the learning profile, the affiliation profile, and the selfish profile, both in prior expectations and at the moment of joining. Similarly, the selfish profile was least common.

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Nakagawa, Tomoyuki, et Shintaro Hashimoto. « On Default Priors for Robust Bayesian Estimation with Divergences ». Entropy 23, n^o 1 (27 décembre 2020) : 29. http://dx.doi.org/10.3390/e23010029.

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This paper presents objective priors for robust Bayesian estimation against outliers based on divergences. The minimum γ-divergence estimator is well-known to work well in estimation against heavy contamination. The robust Bayesian methods by using quasi-posterior distributions based on divergences have been also proposed in recent years. In the objective Bayesian framework, the selection of default prior distributions under such quasi-posterior distributions is an important problem. In this study, we provide some properties of reference and moment matching priors under the quasi-posterior distribution based on the γ-divergence. In particular, we show that the proposed priors are approximately robust under the condition on the contamination distribution without assuming any conditions on the contamination ratio. Some simulation studies are also presented.

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Journal, Baghdad Science. « Bayes and Non-Bayes Estimation Methods for the Parameter of Maxwell-Boltzmann Distribution ». Baghdad Science Journal 14, n^o 4 (3 décembre 2017) : 808–12. http://dx.doi.org/10.21123/bsj.14.4.808-812.

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In this paper, point estimation for parameter ? of Maxwell-Boltzmann distribution has been investigated by using simulation technique, to estimate the parameter by two sections methods; the first section includes Non-Bayesian estimation methods, such as (Maximum Likelihood estimator method, and Moment estimator method), while the second section includes standard Bayesian estimation method, using two different priors (Inverse Chi-Square and Jeffrey) such as (standard Bayes estimator, and Bayes estimator based on Jeffrey's prior). Comparisons among these methods were made by employing mean square error measure. Simulation technique for different sample sizes has been used to compare between these methods.

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Solomito, Matthew J., Erin J. Garibay et Carl W. Nissen. « DECELERATION PHASE MOMENTS : A POTENTIAL CAUSE FOR ELBOW INJURY IN COLLEGIATE LEVEL BASEBALL PITCHERS ». Orthopaedic Journal of Sports Medicine 7, n^o 3_suppl (1 mars 2019) : 2325967119S0007. http://dx.doi.org/10.1177/2325967119s00072.

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Background: Over the past three decades there has been an increase in the incidence of elbow and shoulder pain experienced by baseball pitchers, which can limit or lead to an end of pitching activities. Although there are a number of theories that suggest poor pitching mechanics or throwing breaking pitches prior to skeletal maturity may be the cause, biomechanical investigations have yet to elucidate a single cause for this rise in injuries. It is also well established that the highest stresses and fastest angular velocities experienced by pitchers occurs during the acceleration phase of the pitch cycle, which has led to extensive biomechanical investigations of this portion of the pitching cycle. However, the deceleration phase of the pitch, although 150% longer than the acceleration phase, still requires an abrupt reversal of motion to allow pitchers to get into a fielding position after they have delivered the pitch. Therefore, the purpose of this study was to determine if the elbow joint was subjected to an additional varus stress during the deceleration phase of the pitch cycle. Methods: NCAA Division I and Division III baseball pitchers were recruited for this study and underwent a comprehensive biomechanical pitching evaluation. All pitchers were injury free at the time of data collection and reported no history of an upper extremity injury within the previous six months of the analysis date. Additionally, all pitchers had at least two years of pitching experience. All participants pitched from a 10” mound towards a target with a designated strike zone set 60’6” away. Kinematic data was collected using a 12-camera motion capture system, and kinetic data was calculated using standard inverse dynamic techniques. The typical pitching cycle, starting with lead foot contact and ending with maximum internal rotation of the glenohumeral joint (MIR), was expanded to end when the pedestal foot reached its maximum height; allowing for the analysis of deceleration phase moments at the elbow joint. The deceleration phase elbow varus (EV) moment was compared across multiple pitch types (i.e. fastball, curveball, slider, and change-up) using the type III effects from a random intercept mixed effects model. Additionally, the deceleration phase EV moment was compared to the peak EV moment occurring during the acceleration phase of the pitch cycle. Results: The results of this study are based on 87 baseball pitchers with a mean age of 19.9 ± 1.4 years. All participants pitched a fastball, 78 pitched a curveball, 31 pitched a slider, and 60 pitched a change-up. The results indicated that there was the presence of an elbow varus moment for all pitch types that occurred during the deceleration phase of the pitching cycle after MIR that was on average about half of the peak acceleration phase moment (Table 1). Overall 26% of pitchers pitching a fastball, 33% of pitchers throwing a curveball and change-up, and 55% of pitchers throwing a slider had deceleration EV moments greater than 50% of their peak acceleration phase EV moment. There was a statistically significant difference in the number of pitchers with a deceleration phase EV moment greater than half of the acceleration phase EV moment when pitching the slider when compared to the other pitch types (p=0.029). Conclusion/Significance: The majority of pitching biomechanics research focuses on the acceleration phase of the pitching cycle because the highest speeds and moments are achieved during this portion of the pitch. However, the pitcher’s need to rapidly decelerate during the pitch does expose them to an additional elbow varus moment. This additional moment could be a potential source of injury as it is a second stress exposure for the UCL. Additionally, given that the highest deceleration EV moments were noted in the slider this may potentially explain why pitchers and coaches believe that sliders are more harmful than other pitch types. [Table: see text]

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Mattos Costa, Rafaela, Carina Petsch et Kátia Kellem da Rosa. « LUGAR COMO POTENCIALIDADE NO ENSINO DE HIDROSFERA ». Revista Brasileira de Educação em Geografia 10, n^o 20 (31 décembre 2020) : 411–34. http://dx.doi.org/10.46789/edugeo.v10i20.810.

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O presente artigo objetiva refletir sobre como o ensino da hidrosfera pode ser significado a partir de conceitos geográficos – como lugar e paisagem –, de problemáticas ambientais da bacia hidrográfica local e do conhecimento prévio dos (as) discentes. Foi desenvolvida uma sequência didática, dividida em três momentos, com 25 estudantes de uma turma de 6o ano do Ensino Fundamental de uma escola estadual situada no bairro Bom Jesus (Porto Alegre/RS). O primeiro momento consistiu no levantamento da percepção dos (as) discentes sobre elementos da paisagem. No segundo momento, trabalhou-se com o conceito de bacia hidrográfica. No terceiro momento foram utilizadas fotografias de um trabalho de campo para reflexão sobre problemas ambientais. Conforme relatado pelos (as) estudantes, o contexto ambiental do bairro Bom Jesus apresenta relevantes relações com a hidrosfera, na medida em que a precipitação é sinônimo de problemas ambientais, configurando importantes mudanças na paisagem e no cotidiano dos (as) discentes. Além disso, ressaltamos que foi fundamental criar a sequência didática para construir com os (as) estudantes esquemas sobre hidrosfera no contexto do lugar, para que pudessem representar espaços até então ausentes – como a bacia hidrográfica em que a escola se localiza –, avançando nos níveis de conhecimento. PALAVRAS-CHAVE Ensino Fundamental, Ensino de Geografia Física, Hidrosfera, Paisagem, Lugar. PLACE AS POTENTIALITY IN HYDROSPHERE EDUCATION ABSTRACT This paper aims to reflect on how the teaching of the hydrosphere can be made meaning based on geographical concepts – such place and landscape –, environmental issues in the local watershed and the students prior knowledge. A didactic sequence was developed, divided into three moments, with 25 students from a class of 6th grade of elementary school at a state school located in the Bom Jesus neighborhood (Porto Alegre/RS). The first moment consisted of surveying the students perception of landscape elements. In the second moment, the concept of a hydrographic basin was worked on. In the third moment, photographs of fieldwork were used to reflect on environmental problems. As reported by the students, the environmental context of the Bom Jesus neighborhood has relevant relationships with the hydrosphere, as precipitation is synonymous with environmental problems, configuring important changes in the landscape and in the daily lives of students. In addition, we emphasize that it was essential to create the didactic sequence to build with students schemas about hydrosphere in the context of the place, so that they could represent spaces hitherto absent – such as the hydrographic basin in which the school is located –, advancing in knowledge levels. KEYWORDS Elementary Education, Physical Geography Teaching, Hydrosphere, Landscape, Place.

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Silva, Rui, Ricardo Rodrigues et Carmem Leal. « STUDENT LEARNING MOTIVATIONS IN THE FIELD OF MANAGEMENT WITH (AND WITHOUT) GAMIFICATION ». Journal of Management and Business Education 3, n^o 1 (1 avril 2020) : 47–71. http://dx.doi.org/10.35564/jmbe.2020.0005.

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This study applied the Academic Motivation Scale (AMS) by Vallerand et al. (1992), adapted for the Accounting and Marketing Academic Motivation Scale (AMAMS) in order to analyse who is the motivation level of Portuguese undergraduate students who were attending the Curricular Units (CUs) of Accounting and Marketing, in the beginning, and in the end of 2017/2018 academic year. This longitudinal empirical study reports motivation evolution level of students who studied Accounting and Marketing knowledge areas at two different temporal moments, with and without gamified teaching resource, during the classes. The final goal of this study is to analyse the motivation evolution with and without application of the gamified resources in the teaching process.The study included a total sample of 1923 students divided into two groups: the Gamified Group (GG) and the Control Group (CG) and with their motivations subject to evaluation prior to the beginning of classes (Moment 1 – M1) and at the end of the scheduled classes (Moment 2 – M2). The results enable the verification that the GG students experienced an increase in their Motivation to Learn (IMTK) between M1 and M2 greater than the CG students.

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Jacobson, Nicholas C., et Yeon Joo Chung. « Passive Sensing of Prediction of Moment-To-Moment Depressed Mood among Undergraduates with Clinical Levels of Depression Sample Using Smartphones ». Sensors 20, n^o 12 (24 juin 2020) : 3572. http://dx.doi.org/10.3390/s20123572.

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Prior research has recently shown that passively collected sensor data collected within the contexts of persons daily lives via smartphones and wearable sensors can distinguish those with major depressive disorder (MDD) from controls, predict MDD severity, and predict changes in MDD severity across days and weeks. Nevertheless, very little research has examined predicting depressed mood within a day, which is essential given the large amount of variation occurring within days. The current study utilized passively collected sensor data collected from a smartphone application to future depressed mood from hour-to-hour in an ecological momentary assessment study in a sample reporting clinical levels of depression (N = 31). Using a combination of nomothetic and idiographically-weighted machine learning models, the results suggest that depressed mood can be accurately predicted from hour to hour with an average correlation between out of sample predicted depressed mood levels and observed depressed mood of 0.587, CI [0.552, 0.621]. This suggests that passively collected smartphone data can accurately predict future depressed mood among a sample reporting clinical levels of depression. If replicated in other samples, this modeling framework may allow just-in-time adaptive interventions to treat depression as it changes in the context of daily life.

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Aleixo, Grazielle Anahy de Sousa, Maria Cristina de Oliveira Coelho, Miriam Nogueira Teixeira, Lilian Sabrina Silvestre Andrade, Maria Clara Cunha Paranhos de Oliveira, Flávia Corrêa Maia, Ana Luiza Neves Guimarães Bessa, Joaquim Evêncio-Neto et Emanuela Polimeni Mesquita. « Pre or perioperative period : when is the best time to produce platelet-rich plasma in dogs ? » Medicina Veterinária (UFRPE) 16, n^o 3 (13 décembre 2022) : 199–205. http://dx.doi.org/10.26605/medvet-v16n3-4984.

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When evaluating published studies on the production of platelet-rich plasma (PRP), it is possible to observe that there is no consensus on when blood should be collected and processed. Some perform blood collection before surgery, prior to the administration of drugs, fluids, or any surgical trauma, while others collect blood during the perioperative period. The present objective was to determine the best moment for PRP production based on the platelet count. Blood samples were collected from 20 healthy female dogs at two distinct moments: before surgery, prior to anesthesia and fluid therapy (M0), and later, in the operation room, after administration of the anesthetics and intravenous fluids (M1). To obtain PRP, blood was centrifuged at 1200 rpm for ten minutes, then at 1600 rpm for ten minutes. Results showed that the blood collected at M1 had a 29% decrease in platelet count compared to M0 (highly significant statistical difference). It is recommended that blood collection, which is an essential step for producing platelet-rich plasma, shall be done during the pre-operative period.

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Shen, Bo, et Ang Chen. « Examining the Interrelations among Knowledge, Interests, and Learning Strategies ». Journal of Teaching in Physical Education 25, n^o 2 (avril 2006) : 182–99. http://dx.doi.org/10.1123/jtpe.25.2.182.

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Guided by the Model of Domain Learning (MDL), the study was designed to explore the extent of interrelations among prior knowledge, learning strategies, interests, physical engagement, and learning outcomes in a sixth-grade (N = 91) volleyball unit. Pearson product-moment correlations and a path analysis were conducted for the research purpose. The results showed that students’ prior knowledge, learning strategies, and interests were interrelated. Physical engagement and learning outcomes were directly influenced by the interactions among prior knowledge, interests, and learning strategies. The findings in the study support that learning in physical education is domain-specific and a progressive process that encompasses both cognitive and affective components.

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Jang, G. H., et S. W. Jeong. « Analysis of a Ball Bearing With Waviness Considering the Centrifugal Force and Gyroscopic Moment of the Ball ». Journal of Tribology 125, n^o 3 (19 juin 2003) : 487–98. http://dx.doi.org/10.1115/1.1538618.

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This research presents an analytical method to calculate the characteristics of the ball bearing under the effect of the waviness in its rolling elements and the centrifugal force and gyroscopic moment of ball. The waviness of rolling elements is modeled by using sinusoidal function, and the centrifugal force and gyroscopic. moment of ball are included in the kinematic constraints and force equilibrium equations to produce the nonlinear governing equations. To improve the convergence of the numerical solution of the nonlinear governing equations, it includes the derivatives of the gyroscopic moment and load-deflection constant of each race in the Newton-Raphson formulation. The accuracy of this research is validated by comparing with the prior research, i.e., (i) the contact force, contact angle in case of considering only the centrifugal force and gyroscopic moment of ball, and (ii) the contact force and vibration frequencies in case of considering only the waviness, respectively. It investigates the stiffness, contact force, displacement and vibration frequencies of the ball bearing, considering not only the centrifugal force and gyroscopic moment of ball but also the waviness of the rolling elements.

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Юрий Анатольевич, Огарь,. « Criminal Prosecution Prior to Initiation of Criminal Proceedings : Procedural Statues, Time Limits and Evidence Issues ». ЖУРНАЛ ПРАВОВЫХ И ЭКОНОМИЧЕСКИХ ИССЛЕДОВАНИЙ, n^o 4 (12 décembre 2022) : 166–72. http://dx.doi.org/10.26163/gief.2022.67.16.028.

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Согласно действующему УПК РФ и позиции Конституционного Суда РФ, момент возбуждения уголовного дела одновременно является и моментом начала уголовного преследования. На основе проведенного анализа автор приходит к выводу о том, что такая ситуация не соответствует передовым научным взглядам и опыту некоторых зарубежных стран. В статье предлагается рассмотреть вопрос о возможности смещения начального момента уголовного преследования на более ранний этап уголовного судопроизводства, «внутрь» стадии возбуждения уголовного дела, что могло бы позволить решить целый ряд теоретических проблем. В частности, начало уголовного преследования до возбуждения уголовного дела позволило бы снять многие вопросы, связанные с ограничением средств доказывания и, как следствие, способствовало бы повышению эффективности уголовно-процессуальной деятельности и реализации назначения уголовного судопроизводства. Under the current Code of Criminal Procedure and according to the position of the Russian Constitutional Court the moment of initiation of criminal procedure is also considered to be the starting point of commencement of criminal prosecution. On the basis of the analysis conducted the author concludes that such situation does not correspond to the advanced scientific viewpoints and experience of some foreign countries. The article proposes to address the issue of shifting the initial moment of criminal prosecution to an earlier stage of criminal procedure, placing it «inside» the stage of initiation of criminal procedure that would enable to solve a number of theoretical issues. In particular, the commencement of criminal prosecution prior to initiation of criminal proceeding could settle the issues dealing with limitation of evidence and as a result would promote raising the efficiency of criminal procedure and enable realization of the purpose of criminal proceedings.

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Zimmer, Ulrich. « Microseismic design studies ». GEOPHYSICS 76, n^o 6 (novembre 2011) : WC17—WC25. http://dx.doi.org/10.1190/geo2011-0004.1.

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Microseismic monitoring has become an important part of borehole completions in tight-reservoir formations. Usually, clear objectives for a microseismic survey are set prior to the data acquisition. The possibility of meeting these objectives is determined by the acquisition geometry, the target formation, the completion schedule, and only to a lesser extent, by the data quality itself. Provided is a tutorial on the content and use of prejob modeling and design studies as a tool to anticipate viewing distances, data quantity, location accuracy, event magnitudes, achievable mapping distances, expected waveforms, and noise levels. In addition, potential challenges in meeting the survey objectives can be identified and solutions to these challenges can be devised prior to the survey. For downhole surveys, this involves the evaluation of different sensor array geometries and their impact on the location accuracy in different parts of the expected model. The sensitivity of the event location on the velocity model can be estimated using an initial log-based model. Recently, the detailed characterization of the event mechanism in form of a moment tensor inversion has received increased attention. The accuracy of the inverted moment tensor depends largely on the coverage of the focal sphere, i.e., the distribution of the sensors around the event location. Based on the sensor positions, areas with high- and low-quality moment tensor inversion results can be identified prior to data acquisition through the distribution of the condition number. Depending on the survey objectives and the given constraints, the microseismic design study might show that the survey objectives cannot be met. In this case, it is possible to evaluate alternate technologies, e.g., distributed temperature sensing (DTS), ahead of the project for their potential to meet these challenges.

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Fosha, Diana. « Moment-to-Moment Guidance of Clinical Interventions by AEDP’s Healing-Oriented Transformational Phenomenology : Commentary on Vigoda Gonzalez’s (2018) Case of "Rosa" ». Pragmatic Case Studies in Psychotherapy 14, n^o 2 (15 décembre 2018) : 87. http://dx.doi.org/10.14713/pcsp.v14i2.2038.

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This paper, using the methodology of moment-to-moment microanalysis of videotape-based clinical transcripts, explores how Nicole Vigoda Gonzalez’s (2018) case study manifests AEDP’s fundamental transformational phenomenology in clinical action. Vigoda Gonzalez’s highly effective AEDP therapy of Rosa is informed by AEDP’s first "avatar" or iteration (prior to 2008), at the time, a three-state phenomenology. Yet, a close reading of the case reveals the very transformational phenomena, systematically and abundantly reflected in the author’s clinical data, that necessitated the theoretical and clinical developments of AEDP’s second avatar (post-2008) and the current four-state model of transformational change. It is a validation both of the soundness of this student therapist's clinical work and of the accuracy and power of AEDP’s healing-oriented transformational theory that constructs not in the author’s repertoire are nevertheless reflected and illustrated in the unfolding of Rosa’s treatment. This most interesting and unusual experience further illustrates how a descriptive phenomenology, guided by AEDP’s North Star, i.e., its orientation toward the wired-in healing within, can constitute an empirically sound alternative to the manualization of psychotherapeutic treatments. Also uncannily, this parallels the emphasis in Owen's (2013) multicultural orientation (MCO) framework on the need for "values" or "virtues," such as cultural humility, to "inform therapeutic activities as an alternative to the focus on multicultural competencies."

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Samarakoon, S. M. Samindi M. K., Bartosz Piatek et G. H. M. J. Subashi De Silva. « Investigation of the Flexural Behavior of Preloaded and Pre-Cracked Reinforced Concrete Beams Strengthened with CFRP Plates ». Materials 16, n^o 1 (20 décembre 2022) : 22. http://dx.doi.org/10.3390/ma16010022.

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This paper investigates the flexural behavior of preloaded reinforced concrete (RC) beams, strengthened with Carbon Fiber Reinforced Polymer (CFRP) plates using an experimental program, analytical procedure, and Finite Element Method (FEM) simulation. The RC beams were subjected to preloads of 30%, 50% and 70% of the yielding load, prior to installation of the strengthening system. The eight RC-strengthened beams with a reinforcement configuration of 3Ø12 and two CarboDur S512 plates have been evaluated using bending tests. The failure modes of all the RC-strengthened beams were governed by the widening of flexural cracks within a constant bending zone, followed by debonding of the CFRP plates. The plates were debonding simultaneously or one plate prior to the other plate. The ultimate moment capacity is not significantly reduced while increasing preload levels from 0% to 70%. The moment capacity is increased by 70% to 80% in the CFRP strengthened beams, compared with un-strengthened beams indicating the potential of capacity enhancement that can be attained by externally bonded CFRP.

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