scholarly journals A Three-Dimensional Parametric Biomechanical Rider Model for Multibody Applications

2020 ◽  
Vol 10 (13) ◽  
pp. 4509
Author(s):  
Matteo Bova ◽  
Matteo Massaro ◽  
Nicola Petrone
Keyword(s):  
Center Of Mass ◽  
Three Dimensional ◽  
The Body ◽  
Experimental Comparison ◽  
Minor Effect ◽  
Data Sets ◽  
Data Set ◽  
Multibody Model ◽  
Inertial Parameters ◽  
A Minor

Bicycles and motorcycles are characterized by large rider-to-vehicle mass ratios, thus making estimation of the rider’s inertia especially relevant. The total inertia can be derived from the body segment inertial properties (BSIP) which, in turn, can be obtained from the prediction/regression formulas available in the literature. Therefore, a parametric multibody three-dimensional rider model is devised, where the four most-used BSIP formulas (herein named Dempster, Reynolds-NASA, Zatsiorsky–DeLeva, and McConville–Young–Dumas, after their authors) are implemented. After an experimental comparison, the effects of the main posture parameters (i.e., torso inclination, knee distance, elbow distance, and rider height) are analyzed in three riding conditions (sport, touring, and scooter). It is found that the elbow distance has a minor effect on the location of the center of mass and moments of inertia, while the effect of the knee distance is on the same order magnitude as changing the BSIP data set. Torso inclination and rider height are the most relevant parameters. Tables with the coefficients necessary to populate the three-dimensional rider model with the four data sets considered are given. Typical inertial parameters of the whole rider are also given, as a reference for those not willing to implement the full multibody model.

Conclusion

2006 ◽  
Author(s):  
Soumya Raychaudhuri
Keyword(s):  
Text Mining ◽  
High Throughput ◽  
Relevant Literature ◽  
Critical Role ◽  
The Body ◽  
Data Sets ◽  
Data Set ◽  
New Techniques ◽  
Scientific Text ◽  
Mining Methods

The genomics era has presented many new high throughput experimental modalities that are capable of producing large amounts of data on comprehensive sets of genes. In time there will certainly be many more new techniques that explore new avenues in biology. In any case, textual analysis will be an important aspect of the analysis. The body of the peer-reviewed scientific text represents all of our accomplishments in biology, and it plays a critical role in hypothesizing and interpreting any data set. To altogether ignore it is tantamount to reinventing the wheel with each analysis. The volume of relevant literature approaches proportions where it is all but impossible to manually search through all of it. Instead we must often rely on automated text mining methods to access the literature efficiently and effectively. The methods we present in this book provide an introduction to the avenues that one can employ to include text in a meaningful way in the analysis of these functional genomics data sets. They serve as a complement to the statistical methods such as classification and clustering that are commonly employed to analyze data sets. We are hopeful that this book will serve to encourage the reader to utilize and further develop text mining in their own analyses.

Augmenting Aerodynamic Lift with Jet Lift

1961 ◽  
Vol 65 (612) ◽  
pp. 830-832 ◽  
Author(s):  
Paul D. Arthur ◽  
Edward T. Pitkin
Keyword(s):  
System Size ◽  
The Body ◽  
Minor Effect ◽  
Preliminary Design ◽  
Propulsive Efficiency ◽  
Design Studies ◽  
Lifting Surfaces ◽  
A Minor ◽  
Propulsive Jet ◽  
Aerodynamic Lift

Downward deflection of a propulsive jet may be employed to augment aerodynamic lift in an advantageous manner. In each situation there occurs a simple optimisation when the losses due to reduced propulsive efficiency are contrasted with the gains which accrue from jet lifting. Typical cases will be considered here for wing dominant configurations, i.e. cases where the lifting surfaces contribute most of the drag, with the body contributing but a minor effect. Variable geometry of both airframe and engine is implicitly assumed so that results may be applied to preliminary design studies which will determine the relative propulsion system size and wing area.

scholarly journals Effect of Leg Dominance on The Center-of-Mass Kinematics During an Inside-of-the-Foot Kick in Amateur Soccer Players

2014 ◽  
Vol 42 (1) ◽  
pp. 51-61 ◽  
Author(s):  
Matteo Zago ◽  
Andrea Francesco Motta ◽  
Andrea Mapelli ◽  
Isabella Annoni ◽  
Christel Galvani ◽  
...  
Keyword(s):  
Body Movement ◽  
Center Of Mass ◽  
Three Dimensional ◽  
The Body ◽  
Soccer Players ◽  
Upper Body ◽  
Whole Body ◽  
Movement Velocity ◽  
Ground Support ◽  
Analysis System

Abstract Soccer kicking kinematics has received wide interest in literature. However, while the instep-kick has been broadly studied, only few researchers investigated the inside-of-the-foot kick, which is one of the most frequently performed techniques during games. In particular, little knowledge is available about differences in kinematics when kicking with the preferred and non-preferred leg. A motion analysis system recorded the three-dimensional coordinates of reflective markers placed upon the body of nine amateur soccer players (23.0 ± 2.1 years, BMI 22.2 ± 2.6 kg/m2), who performed 30 pass-kicks each, 15 with the preferred and 15 with the non-preferred leg. We investigated skill kinematics while maintaining a perspective on the complete picture of movement, looking for laterality related differences. The main focus was laid on: anatomical angles, contribution of upper limbs in kick biomechanics, kinematics of the body Center of Mass (CoM), which describes the whole body movement and is related to balance and stability. When kicking with the preferred leg, CoM displacement during the ground-support phase was 13% higher (p<0.001), normalized CoM height was 1.3% lower (p<0.001) and CoM velocity 10% higher (p<0.01); foot and shank velocities were about 5% higher (p<0.01); arms were more abducted (p<0.01); shoulders were rotated more towards the target (p<0.01, 6° mean orientation difference). We concluded that differences in motor control between preferred and non-preferred leg kicks exist, particularly in the movement velocity and upper body kinematics. Coaches can use these results to provide effective instructions to players in the learning process, moving their focus on kicking speed and upper body behavior

Additive and heterotic breed effects in the genetic evaluation of pig sire breeds

2006 ◽  
Vol 82 (4) ◽  
pp. 455-462 ◽  
Author(s):  
J. Wolf ◽  
D. Peškovičová ◽  
E. Žáková ◽  
E. Groeneveld
Keyword(s):  
Average Daily Gain ◽  
Field Performance ◽  
Breeding Value ◽  
Data Sets ◽  
Large White ◽  
Data Set ◽  
Meat Content ◽  
Value Estimation ◽  
A Minor ◽  
Daily Gain

AbstractThe data sets consisted of field performance data from 54 848 purebred and 16 175 crossbred animals (Czech data set, CZ) and 16 610 purebred and 9 228 crossbred animals (Slovak data set, SK). Animals from the following breeds were included: Duroc, Hampshire, Piétrain, sire line of Large White (CZ) or Yorkshire (SK), Czech Meat pig (CZ) or Slovak Meat pig (SK), Belgian Landrace (SK). Two-trait animal models were calculated for average daily gain from birth to the end of the field test (ADG) and lean meat content (LM, only in CZ) or backfat thickness (BF, only in SK). The models included additive breed and breed heterotic effects. Piétrain was the breed with the highest LM and the lowest BF. The additive genetic breed effect was about 1·5% LM (CZ) in comparison with Large White or −0·4 mm BF (SK) in comparison to Yorkshire. The sire line of Large White (CZ) or the Yorkshire breed (SK) clearly exceeded all the remaining sire breeds in ADG (on average by 30 to 50 g/day). There was a clear tendency to negative heterosis in LM in all crossbred combinations (CZ). In BF, heterotic effects between −0·2 mm and +0·3 mm were estimated, mostly not being significant (SK). The estimates of the heterotic effects for ADG were positive throughout. Higher values up to 40 g/day (7%) were observed in the Czech data set. Though heterotic breed effects are of some importance especially for ADG, their inclusion in the equations for breeding value estimation will have only a minor impact on the predicted breeding values.

scholarly journals A quantitative analysis of environmental associations in sauropod dinosaurs

Paleobiology ◽  
2010 ◽  
Vol 36 (2) ◽  
pp. 253-282 ◽  
Author(s):  
Philip D. Mannion ◽  
Paul Upchurch
Keyword(s):  
Positive Association ◽  
Large Data ◽  
The Body ◽  
Time Range ◽  
Data Sets ◽  
Coastal Environments ◽  
Carbonate Platforms ◽  
Significant Positive Association ◽  
Data Set ◽  
Body Fossil

Both the body fossils and trackways of sauropod dinosaurs indicate that they inhabited a range of inland and coastal environments during their 160-Myr evolutionary history. Quantitative paleoecological analyses of a large data set of sauropod occurrences reveal a statistically significant positive association between non-titanosaurs and coastal environments, and between titanosaurs and inland environments. Similarly, “narrow-gauge” trackways are positively associated with coastal environments and “wide-gauge” trackways are associated with inland environments. The statistical support for these associations suggests that this is a genuine ecological signal: non-titanosaur sauropods preferred coastal environments such as carbonate platforms, whereas titanosaurs preferred inland environments such as fluvio-lacustrine systems. These results remain robust when the data set is time sliced and jackknifed in various ways. When the analyses are repeated using the more inclusive groupings of titanosauriforms and Macronaria, the signal is weakened or lost. These results reinforce the hypothesis that “wide-gauge” trackways were produced by titanosaurs. It is commonly assumed that the trackway and body fossil records will give different results, with the former providing a more reliable guide to the habitats occupied by extinct organisms because footprints are produced during life, whereas carcasses can be transported to different environments prior to burial. However, this view is challenged by our observation that separate body fossil and trackway data sets independently support the same conclusions regarding environmental preferences in sauropod dinosaurs. Similarly, analyzing localities and individuals independently results in the same environmental associations. We demonstrate that conclusions about environmental patterns among fossil taxa can be highly sensitive to an investigator's choices regarding analytical protocols. In particular, decisions regarding the taxonomic groupings used for comparison, the time range represented by the data set, and the criteria used to identify the number of localities can all have a marked effect on conclusions regarding the existence and nature of putative environmental associations. We recommend that large data sets be explored for such associations at a variety of different taxonomic and temporal scales.

scholarly journals Accuracy of Low-Cost Alternative Facial Scanners: A Prospective Cohort Study.

2021 ◽  
Author(s):  
Alexander K. Bartella ◽  
Josefine Laser ◽  
Mohammad Kamal ◽  
Dirk Halama ◽  
Michael Neuhaus ◽  
...  
Keyword(s):  
Low Cost ◽  
Three Dimensional ◽  
Neck Surgery ◽  
Clinical Analysis ◽  
Smart Device ◽  
Data Sets ◽  
Average Deviation ◽  
Technical Improvement ◽  
Data Set ◽  
Significant Difference

Abstract Introduction: Three-dimensional facial scan images have been showing an increasingly important role in peri-therapeutic management of oral and maxillofacial and head and neck surgery cases. Face scan images can be open using optical facial scanners utilizing line-laser, stereophotography, structured light modality, or from volumetric data obtained from cone beam computed tomography (CBCT). The aim of this study is to evaluate, if two low-cost procedures for creating a three-dimensional face scan images are able to produce a sufficient data set for clinical analysis. Materials and methods: 50 healthy volunteers were included in the study. Two test objects with defined dimensions were attached to the forehead and the left cheek. Anthropometric values were first measured manually, and consecutively, face scans were performed with a smart device and manual photogrammetry and compared to the manually measured data sets.Results: Anthropometric distances on average deviated 2.17 mm from the manual measurement (smart device scanning 3.01 mm vs. photogrammetry 1.34 mm), with 7 out of 8 deviations were statistically significant. Of a total of 32 angles, 19 values showed a significant difference to the original 90° angles. The average deviation was 6.5° (smart device scanning 10.1° vs. photogrammetry 2.8°).Conclusion: Manual photogrammetry with a regular photo-camera shows higher accuracy than scanning with smart device. However, the smart device was more intuitive in handling and further technical improvement of the cameras used should be watched carefully.

Quantifying Segmental Contributions to Center-of-Mass Motion During Dynamic Continuous Support Surface Perturbations Using Simplified Estimation Models

2020 ◽  
Vol 36 (4) ◽  
pp. 198-208
Author(s):  
Alison Schinkel-Ivy ◽  
Vicki Komisar ◽  
Carolyn A. Duncan
Keyword(s):  
Balance Control ◽  
Center Of Mass ◽  
Three Dimensional ◽  
The Body ◽  
Whole Body ◽  
Mass Motion ◽  
Support Surface ◽  
Body Segments ◽  
Body Model ◽  
Full Body

Investigating balance reactions following continuous, multidirectional, support surface perturbations is essential for improving our understanding of balance control in moving environments. Segmental motions are often incorporated into rapid balance reactions following external perturbations to balance, although the effects of these motions during complex, continuous perturbations have not been assessed. This study aimed to quantify the contributions of body segments (ie, trunk, head, upper extremity, and lower extremity) to the control of center-of-mass (COM) movement during continuous, multidirectional, support surface perturbations. Three-dimensional, whole-body kinematics were captured while 10 participants experienced 5 minutes of perturbations. Anteroposterior, mediolateral, and vertical COM position and velocity were calculated using a full-body model and 7 models with reduced numbers of segments, which were compared with the full-body model. With removal of body segments, errors relative to the full-body model increased, while relationship strength decreased. The inclusion of body segments appeared to affect COM measures, particularly COM velocity. Findings suggest that the body segments may provide a means of improving the control of COM motion, primarily its velocity, during continuous, multidirectional perturbations, and constitute a step toward improving our understanding of how the limbs contribute to balance control in moving environments.

Semi-Automated Roller Parameters Extraction from Terrestrial Lidar

2021 ◽  
Vol 87 (12) ◽  
pp. 879-890
Author(s):  
Sagar S. Deshpande ◽  
Mike Falk ◽  
Nathan Plooster
Keyword(s):  
Rotation Axis ◽  
Moving Average ◽  
Three Dimensional ◽  
Data Sets ◽  
Steel Mill ◽  
Data Set ◽  
Terrestrial Lidar ◽  
Two Dimensional Image ◽  
Average Rotation

Rollers are an integral part of a hot-rolling steel mill. They transport hot metal from one end of the mill to another. The quality of the steel highly depends on the surface quality of the rollers. This paper presents semi-automated methodologies to extract roller parameters from terrestrial lidar points. The procedure was divided into two steps. First, the three-dimensional points were converted to a two-dimensional image to detect the extents of the rollers using fast Fourier transform image matching. Lidar points for every roller were iteratively fitted to a circle. The radius and center of the fitted circle were considered as the average radius and average rotation axis of the roller, respectively. These parameters were also extracted manually and were compared to the measured parameters for accuracy analysis. The proposed methodology was able to extract roller parameters at millimeter level. Erroneously identified rollers were identified by moving average filters. In the second step, roller parameters were determined using the filtered roller points. Two data sets were used to validate the proposed methodologies. In the first data set, 366 out of 372 rollers (97.3%) were identified and modeled. The second, smaller data set consisted of 18 rollers which were identified and modelled accurately.

Geostatistical Joint Interpretation of Gravity and Magnetotelluric Data of the US Cordillera

2021 ◽  
Author(s):  
Mohammad Shehata ◽  
Hideki Mizunaga
Keyword(s):  
Gravity Data ◽  
Three Dimensional ◽  
Data Sets ◽  
Spatial Expansion ◽  
Magnetotelluric Data ◽  
Data Set ◽  
Entire Area ◽  
Mean Values ◽  
Local Means ◽  
The Us

&lt;p&gt;Long-period magnetotelluric and gravity data were acquired to investigate the US cordillera's crustal structure. The magnetotelluric data are being acquired across the continental USA on a quasi-regular grid of &amp;#8764;70 km spacing as an electromagnetic component of the National Science Foundation EarthScope/USArray Program. International Gravimetreique Bureau compiled gravity Data at high spatial resolution. Due to the difference in data coverage density, the geostatistical joint integration was utilized to map the subsurface structures with adequate resolution. First, a three-dimensional inversion of each data set was applied separately.&lt;/p&gt;&lt;p&gt;The inversion results of both data sets show a similarity of structure for data structuralizing. The individual result of both data sets is resampled at the same locations using the kriging method by considering each inversion model to estimate the coefficient. Then, the Layer Density Correction (LDC) process's enhanced density distribution was applied to MT data's spatial expansion process. Simple Kriging with varying Local Means (SKLM) was applied to the residual analysis and integration. For this purpose, the varying local means of the resistivity were estimated using the corrected gravity data by the Non-Linear Indicator Transform (NLIT), taking into account the spatial correlation. After that, the spatial expansion analysis of MT data obtained sparsely was attempted using the estimated local mean values and SKLM method at the sections where the MT survey was carried out and for the entire area where density distributions exist. This research presents the integration results and the stand-alone inversion results of three-dimensional gravity and magnetotelluric data.&lt;/p&gt;

Uncertainty Reduction on the Identification of the Inertial Parameters Based on a Complex 3D Motion

2010 ◽  
Author(s):  
Juan P. Barreto M. ◽  
Luis E. Munoz C.
Keyword(s):  
Center Of Mass ◽  
Algebraic Method ◽  
Rigid Bodies ◽  
The Body ◽  
Inertia Tensor ◽  
Identification System ◽  
3D Motion ◽  
Inertial Parameters ◽  
Static Experiment ◽  
Measuring Unit

The uncertainty on the identification of the inertial parameters of rigid bodies can be reduced by studying the motion for the identification experiments. This paper presents a method for measuring the center of mass and the inertia tensor of a rigid body by generating a complex 3D motion. The proposed method is intended to reduce the time consumed by the experiment and the post-processing of the data. This reduction on the time is achieved by using the same assembly for the center of mass and inertia tensor identification experiments as well as an algebraic method for the identification. The experimental setup consists on a Stewart Platform for the generation of the motion, a load cell and an inertial measuring unit. A study on the reduction of the uncertainty was developed. It was found that the uncertainty on the identification of the center of mass can be reduced with a static experiment that takes the object to different orientations, improving the numerical condition of the identification system. The uncertainty on the inertia tensor identification is reduced when the motion of the body is generated relative to different axes in space. The method was first tested on simulations to estimate the uncertainty and then validated experimentally.

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