kinematic velocity
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2019 ◽  
Vol 29 (02) ◽  
pp. 1850037 ◽  
Author(s):  
Pedro Gómez-Vilda ◽  
Zoltan Galaz ◽  
Jiri Mekyska ◽  
José M. Ferrández Vicente ◽  
Andrés Gómez-Rodellar ◽  
...  

Neurodegenerative pathologies as Parkinson’s Disease (PD) show important distortions in speech, affecting fluency, prosody, articulation and phonation. Classically, measurements based on articulation gestures altering formant positions, as the Vocal Space Area (VSA) or the Formant Centralization Ratio (FCR) have been proposed to measure speech distortion, but these markers are based mainly on static positions of sustained vowels. The present study introduces a measurement based on the mutual information distance among probability density functions of kinematic correlates derived from formant dynamics. An absolute kinematic velocity associated to the position of the jaw and tongue articulation gestures is estimated and modeled statistically. The distribution of this feature may differentiate PD patients from normative speakers during sustained vowel emission. The study is based on a limited database of 53 male PD patients, contrasted to a very selected and stable set of eight normative speakers. In this sense, distances based on Kullback–Leibler divergence seem to be sensitive to PD articulation instability. Correlation studies show statistically relevant relationship between information contents based on articulation instability to certain motor and nonmotor clinical scores, such as freezing of gait, or sleep disorders. Remarkably, one of the statistically relevant correlations point out to the time interval passed since the first diagnostic. These results stress the need of defining scoring scales specifically designed for speech disability estimation and monitoring methodologies in degenerative diseases of neuromotor origin.


Filomat ◽  
2018 ◽  
Vol 32 (5) ◽  
pp. 1547-1558 ◽  
Author(s):  
Yanyan Dai ◽  
Dianwei Qian ◽  
Sukgyu Lee

This paper presents transporting algorithm for multiple robots to transport a concave or convex object. The object transporting includes three processes: calculating proper points process; approaching proper points process; and transporting an object process. Using fuzzy sliding mode control algorithm, we design a kinematic velocity controller. We also propose a dynamic torque controller by adaptive sliding mode control algorithm. Finally, simulations and experiment show good performance of proposed methods.


Loquens ◽  
2017 ◽  
Vol 4 (1) ◽  
pp. 036
Author(s):  
Pedro Gómez ◽  
Jiri Mekyska ◽  
Andrés Gómez ◽  
Daniel Palacios ◽  
Victoria Rodellar ◽  
...  

Parkinson Disease (PD) is a neuromotor illness affecting general movements of different muscles, those implied in speech production being among them. The relevance of speech in monitoring illness progression has been documented in these last two decades. Most of the studies have concentrated in dysarthria and dysphonia induced by the syndrome. The present work is devoted to explore how PD affects the dynamic behavior of the speech neuromotor biomechanics (neuromechanics) involved in deficient articulation (dysarthria), in contrast to classical measurements based on static features as extreme and central vowel triangle positions. A statistical distribution of the kinematic velocity of the lower jaw and tongue is introduced, which presents interesting properties regarding pattern recognition and classification. This function may be used to establish distances between different articulation profiles in terms of information theory. Results show that these distances are correlated with a set of tests currently used by neurologists in PD progress evaluation, and could be used in elaborating new speech testing protocols.


2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Mingyang Wang ◽  
Songlin Yue ◽  
Ning Zhang ◽  
Kanghua Gao ◽  
Derong Wang

For underground explosions, a thin to medium thickness layer near the cavity of an explosion can be considered a theoretical shell structure. Detonation products transmit the effective energy of explosives to this shell which can expand thus leading to irreversible deformation of the surrounding medium. Based on mass conservation, incompressible conditions, and boundary conditions, the possible kinematic velocity fields in the plastic zone are established. Based on limit equilibrium theory, this work built equations of material resistance corresponding to different possible kinematic velocity fields. Combined with initial conditions and boundary conditions, equations of motion and material resistance are solved, respectively. It is found that critical depth of burial is positively related to a dimensionless impact factor, which reflects the characteristics of the explosives and the surrounding medium. Finally, an example is given, which suggests that this method is capable of calculating the critical depth of burial and the calculated results are consistent with empirical results.


2015 ◽  
Vol 63 (3) ◽  
pp. 370-381 ◽  
Author(s):  
Ádám Nagy ◽  
Tassos Polichronopoulos ◽  
András Gáspárdy ◽  
László Solti ◽  
Sándor Cseh

Motility is one of the most important characteristics associated with the fertilising ability of spermatozoa indicating their viability and structural integrity. Therefore, the examination of motility constitutes an integral part of semen analysis. Computer-assisted semen analysis (CASA) allows an accurate and objective assessment of different sperm motion characteristics with high repeatability. The aim of this study was to evaluate the different kinematic (velocity) parameters of frozen/thawed bull semen and determine if any of them could be correlated with their fertilising capability after insemination based on the achieved pregnancy rate. Ejaculates from 10 bulls were collected and frozen. The kinematic/velocity parameters of spermatozoa were measured by CASA and compared to the pregnancy results of almost 9,000 females artificially inseminated (AI) with frozen semen of any of the 10 tested bulls. The data of the experiments are summarised mainly with a focus on the effects of individual velocities (curvilinear velocity: VCL, straight-line velocity: VSL, average path velocity: VAP) on fertility rather than on the influence of progressive motility as a whole. We conclude that VAP is the most useful semen motility characteristic which has clinical relevance in the prediction of fertility.


2013 ◽  
Vol 850-851 ◽  
pp. 1220-1224
Author(s):  
Jun Qi Fan ◽  
Jun Xia Yang ◽  
Fu Li Kong ◽  
Kui Huang

About the prediction of the biological damage effects on the lung of human under explosion wave, there are three different criterions, including excessive pressure-impulse criterion, kinematic velocity criterion and specific energy criterion. In the paper, based on the established three criterions and the practical anatomical structure of lung , a new theoretical model on blast lung injury from an explosion is developed. In the present model, the problem of blast lung injury is simplified as the one-dimensional propagation of stress wave in metal foam. Results show that the failure stress of the lung is 0.036~0.072 MPa, and the three criterions can convert to each other.


2011 ◽  
Vol 403-408 ◽  
pp. 5061-5067 ◽  
Author(s):  
Mostafa Ghayour ◽  
Amir Zareei

In this article a proper mechanism for a hexapod spider-like mobile robot is presented. By using of geometrical method, inverse kinematic of the robot is analyzed. In further via differential kinematic, velocity of the joint variables is specified. Then inverse kinematic of the robot is solved for a specific motion and the related results are shown and analyzed.


2008 ◽  
Vol 44-46 ◽  
pp. 361-366 ◽  
Author(s):  
Rui Shi Zhang ◽  
J.Z. Pan ◽  
L.W. Wang

The effect of formulation (filler’s kind and amount, liquid’s kind and concentration required for granulation) and spheronization time on characterization of alumina based pellets parameters (pellets size distribution, roundness and aspect ratio) were investigated. Two schemes were successfully proofed by extrusion/spheronization. The mean volume particle diameter was found to have a profound effect on the formulation and processing parameters. Alumina powder with large mean volume particle diameter showed different mechanism of action with coupling agent. With the surface modification, the water required for granulation had decreased. The existing formal and kinematic velocity of the water had a direct effect on the processing parameter of the extrusion and spheronization. Spheronization time from 2 to 10 min had a pronounced effect on roundness and aspect ratio. No changes in roundness and aspect ratio were observed from 10 to 20 min of spheronization time.


1999 ◽  
Vol 28 ◽  
pp. 221-230 ◽  
Author(s):  
Richard C. A. Hindmarsh

AbstractThe geomorphological effects of ice sliding over till, internal deformation of till and till sliding over bedrock are considered. Two questions are examined: (1) is the till-sheet flow unstable, i.e. is a layer of uniform thickness maintained or not, and (2) does the slip of till over bedrock cause amplification of relief of the bedrock? Such instabilities seem to be necessary to explain such features as drumlins and whaleback forms.It is found that the answer to (1) and (2) depends on the position of the system in a parameter space, defined by the till rheology, and applied shear stress, the effective pressure at the ice—till interface, the thickness of ice and till and the wavelength of the instability. Two configurations are considered: one where the wavelength of the perturbation is much less than the the ice-thickness, which is related to the classical Nye—Kamb solution for flow over bumps; and one where the wavelength is much greater than the ice thickness, where the mechanics are described by the shallow-ice approximation. In both cases, substantial areas of parameter space, where till-sheet and bedrock modes are unstable, are found. The conceptually related Smalley—Unwin bifurcation is re-examined.The physical mechanisms by which ice and till flows couple are examined. At very short wavelengths (~10 m), the ice is so rigid that it forces till waves to move at the ice velocity; while at long wavelengths (~1000 m), the flows become essentially uncoupled and till waves move at the kinematic velocity. At intermediate wavelengths (~100 m), high growth rates occur ; this is postulated to be the scale of drumlin seeding.


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