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Tytuł:
Application of an artificial neural network and morphing techniques in the redesign of dysplastic trochlea
Autorzy:
Cho, K. J.
Müller, J. H.
Erasmus, P. J.
Dejour, D.
Scheffer, C.
Powiązania:
https://bibliotekanauki.pl/articles/307312.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
artificial neural network
trochlea redesign
trochlear dysplasia
trochleoplasty
trochlea morphing
sztuczna sieć neuronowa
bloczek
biomechanika
Opis:
Segmentation and computer assisted design tools have the potential to test the validity of simulated surgical procedures, e.g., trochleoplasty. A repeatable measurement method for three dimensional femur models that enables quantification of knee parameters of the distal femur is presented. Fifteen healthy knees are analysed using the method to provide a training set for an artificial neural network. The aim is to use this artificial neural network for the prediction of parameter values that describe the shape of a normal trochlear groove geometry. This is achieved by feeding the artificial neural network with the unaffected parameters of a dysplastic knee. Four dysplastic knees (Type A through D) are virtually redesigned by way of morphing the groove geometries based on the suggested shape from the artificial neural network. Each of the four resulting shapes is analysed and compared to its initial dysplastic shape in terms of three anteroposterior dimensions: lateral, central and medial. For the four knees the trochlear depth is increased, the ventral trochlear prominence reduced and the sulcus angle corrected to within published normal ranges. The results show a lateral facet elevation inadequate, with a sulcus deepening or a depression trochleoplasty more beneficial to correct trochlear dysplasia.
Źródło:
Acta of Bioengineering and Biomechanics; 2014, 16, 2; 75-84
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of the Teager Kaiser Energy Operator in an autonomous burst detector to create onset and offset profiles of forearm muscles during reach-to-grasp movements
Autorzy:
Krabben, T.
Prange, G. B.
Kobus, H. J.
Rietman, J. S.
Buurke, J. H.
Powiązania:
https://bibliotekanauki.pl/articles/306581.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
elektromiografia
AGLR
Teager-Kaiser
electromyography
timing
reach
grasp
Opis:
Purpose: The primary aim of this study is to investigate the potential benefit of the Teager–Kaiser Energy Operator (TKEO) as data pre-processor, in an autonomous burst detection method to classify electromyographic signals of the (fore)arm and hand. For this purpose, optimal settings of the burst detector, leading to minimal detection errors, need to be known. Additionally, the burst detector is applied to real muscle activity recorded in healthy adults performing reach-to-grasp movements. Methods: The burst detector was based on the Approximated Generalized Likelihood Ratio (AGLR). Simulations with synthesized electromyographic (EMG) traces with known onset and offset times, yielded optimal settings for AGLR parameters “window width” and “threshold value” that minimized detection errors. Next, comparative simulations were done with and without TKEO data pre-processing. Correct working of the burst detector was verified by applying it to real surface EMG signals obtained from arm and hand muscles involved in a submaximal reach-to-grasp task, performed by healthy adults. Results: Minimal detection errors were found with a window width of 100 ms and a detection threshold of 15. Inclusion of the TKEO contributed significantly to a reduction of detection errors. Application of the autonomous burst detector to real data was feasible. Conclusions: The burst detector was able to classify muscle activation and create Muscle Onset Offset Profiles (MOOPs) autonomously from real EMG data, which allows objective comparison of MOOPs obtained from movement tasks performed in different conditions or from different populations. The TKEO contributed to improved performance and robustness of the burst detector.
Źródło:
Acta of Bioengineering and Biomechanics; 2016, 18, 4; 135-144
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A finite element model of the L4-L5-S1 human spine segment including the heterogeneity and anisotropy of the discs
Autorzy:
Jaramillo, H.
Gomez, L.
Garcia, J. J.
Powiązania:
https://bibliotekanauki.pl/articles/951814.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
kręgosłup
metoda elementów skończonych
segment L4-L5-S1
krążek międzykręgowy
model hipersprężysty
intervertebral disc
L4-L5-S1 segment
finite element model
human spine
hyperelastic model
Opis:
With the aim to study disc degeneration and the risk of injury during occupational activities, a new finite element (FE) model of the L4-L5-S1 segment of the human spine was developed based on the anthropometry of a typical Colombian worker. Beginning with medical images, the programs CATIA and SOLIDWORKS were used to generate and assemble the vertebrae and create the soft structures of the segment. The software ABAQUS was used to run the analyses, which included a detailed model calibration using the experimental step-wise reduction data for the L4-L5 component, while the L5-S1 segment was calibrated in the intact condition. The range of motion curves, the intradiscal pressure and the lateral bulging under pure moments were considered for the calibration. As opposed to other FE models that include the L5-S1 disc, the model developed in this study considered the regional variations and anisotropy of the annulus as well as a realistic description of the nucleus geometry, which allowed an improved representation of experimental data during the validation process. Hence, the model can be used to analyze the stress and strain distributions in the L4-L5 and L5-S1 discs of workers performing activities such as lifting and carrying tasks.
Źródło:
Acta of Bioengineering and Biomechanics; 2015, 17, 2; 15-24
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elastic constants influence on the L4-L5-S1 annuli fibrosus behavior, a probabilistic finite element analysis
Autorzy:
Jaramillo, H. E.
Garcia, J. J.
Powiązania:
https://bibliotekanauki.pl/articles/307431.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
FEM
hiperelastyczność
krążek międzykręgowy
analiza probabilistyczna
finite element analysis
hyperelastic
range of motion
intervertebral discs
probabilistic analysis
sensitivity factor
Opis:
A probabilistic finite element (FE) analysis of the L4-L5 and L5-S1 human annulus fibrosus (AF) was conducted to obtain a better understanding of the biomechanics of the AF and to quantify its influence on the range of motion (ROM) of the L4-L5 and L5-S1 segments. Methods: The FE models were composed of the AF and the upper and lower endplates. The AF was represented as a continuous material composed of a hyperelastic isotropic Yeoh matrix reinforced with two families of fibers described with an exponential energy function. The caudal endplate was fully restricted and 8 Nm pure moment was applied to the cranial endplate in flexion, extension, lateral flexion and axial rotation. The mechanical constants were determined randomly based on a normal distribution and average values reported. Results: Results of the 576 models show that the ROM was more sensitive to the initial stiffness of the fibers rather than to the stiffening coefficient represented in the exponential function. The ROM was more sensitive to the input variables in extension, flexion, axial rotation and lateral bending. The analysis showed an increased probability for the L5-S1 ROM to be higher in flexion, extension and axial rotation, and smaller in lateral flexion, with respect to the L4-L5 ROM. Conclusions: An equation was proposed to obtain the ROM as a function of the elastic constants of the fibers and it may be used to facilitate the calibration process of the human spine segments and to understand the influence of each elastic constant on the ROM.
Źródło:
Acta of Bioengineering and Biomechanics; 2017, 19, 4; 3-12
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Strength and Deformation of Sand-Tire Rubber Mixtures (STRM): An Experimental Study
Autorzy:
Al-Rkaby, Alaa H. J.
Powiązania:
https://bibliotekanauki.pl/articles/178850.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
tire rubber
shear strength
deformation
major principal strains
minor principal strains
intermediate principal strains
Opis:
Waste material such as used tires is increasing every year, which poses environmental problems. However, such material has been used in several geotechnical applications as alternative lightweight backfill in highway embankments and/or behind retaining walls, providing environmental, economic and technical benefits. These applications require knowledge of engineering properties of soil-tire rubber mixtures. The present study aims to show the possibility of tire rubber usage in sand by evaluating the shear strength and deformability of sand mixed with granulated rubber, in weight percentages between 0 and 50%. The tire rubber content was found to influence the stress-strain and deformation behavior of the mixtures. The shear strength of sand mixed with 10% or 20% tire rubber was higher than that measured for sand only. However, the trend for TRC = 30–50% was different. Samples with a rubber content of 30-50% exhibited a rapid decrease in the stress ratio compared with that of sand. The major principal strain at maximum stress ratio was found to increase with increasing tire rubber content. However, it was observed that the lateral strains (minor and intermediate principal strains) of samples reduced significantly with the addition of tire rubber to the sand.
Źródło:
Studia Geotechnica et Mechanica; 2019, 41, 2; 74-80
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On types of responsiveness in the theory of voting
Autorzy:
Holler, M. J.
Nurmi, H.
Powiązania:
https://bibliotekanauki.pl/articles/406595.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
plausible opinion aggregation
monotonicity
no-show paradox
Opis:
In mathematics, monotonicity is used to denote the nature of the connection between variables. Hence for example, a variable is said to be a monotonically increasing function of another variable if an increase in the value of the latter is always associated with an increase in the other variable. In the theory of voting and the measurement of a priori voting power one encounters, not one, but several concepts that are closely related to the mathematical notion of monotonicity. We deal with such notions focusing particularly on their role in capturing key aspects of plausible opinion aggregation. Further, we outline approaches to analyzing the relationship of opinion aggregation and voting power and thereby contribute to our understanding of major components that determine the outcome of voting.
Źródło:
Operations Research and Decisions; 2016, 26, 2; 87-106
2081-8858
2391-6060
Pojawia się w:
Operations Research and Decisions
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mineral preconcentration using near infrared sensor-based sorting
Autorzy:
Iyakwari, S.
Glass, H. J.
Powiązania:
https://bibliotekanauki.pl/articles/109720.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
near infrared
copper
hematite
preconcentration
strategy
intimate mixtures
moisture
Opis:
This paper predicts qualitatively and quantitatively the near infrared activity of individual minerals in simple and complex mineral associations using mixtures of common alteration minerals found in a copper ore. It was found that spectra dominance in most cases is dependent on any or combination of mineral composition, relative proportion or concentration and/or mineral accessibility or sensitivity to near infrared radiation. The analysis of results also indicated that, in most cases, only freely occurring waste, such as clays (kaolinite and/or muscovite) and calcite, can be targeted for discrimination. In this paper, a strategy for the application of near infrared for preconcentration of copper bearing minerals like chrysocolla and malachite from coarse ore particles was proposed. Other applications also considered in this paper include preconcentration of hematite from associated clays and carbonate waste, and the determination of moisture content in kaolinitic clays.
Źródło:
Physicochemical Problems of Mineral Processing; 2015, 51, 2; 661-674
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Feature extraction of molten pool for laser welding quality real-time inspection
Autorzy:
Zhang, J
Yin, H
Huang, H
Yang, R
Yang, J
Li, Y
Powiązania:
https://bibliotekanauki.pl/articles/173597.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
laser materials processing
process monitoring and control
image analysis
Opis:
This paper proposed an image feature extraction method for laser welding molten pool inspection based on cellular neural network. TC4 titanium alloy thin plates were welded by Nd:YAG pulsed laser. A coaxial machine vision system was designed to acquire molten pool images. An auxiliary lighting source was employed to improve the molten pool image quality. By analyzing molten pool images, the welding defects such as fenestration or insufficient depth were identified. These results can be used as a feedback signal for laser power control. Experimental results showed that the proposed method can be used to improve laser welding quality.
Źródło:
Optica Applicata; 2015, 45, 4; 523-533
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Immobilization of rambutan (Nephelium lappaceum) peel as a sorbent for Basic Fuchsin removal
Autorzy:
Lee, H.-J.
Ong, S.-T.
Powiązania:
https://bibliotekanauki.pl/articles/207651.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
fuchsin
Fourier transform infrared spectrophotometry
FTIR
Nephelium lappaceum
fuksyna
spektroskopia w podczerwieni z transformatą Fouriera
Opis:
The potential of rambutan (Nephelium lappaceum) peel as a low-cost adsorbent in an immobilized condition to remove Basic Fuchsin from aqueous solution was studied. The effect of initial dye concentration, contact time, pH and adsorbent dosage for the dye removal was studied at room temperature (26±2 °C). Infrared spectrum of rambutan peel indicates the presence of C–O, –OH and C=C functional groups. The adsorption rate was found to be high at the first 30 min and the process reached equilibrium after 3 h with more than 80% of dye being removed. The uptake of Basic Fuchsin was more promising at pH slightly above 7. The study of sorption model and kinetic model showed that the adsorption of Basic Fuchsin on rambutan peel conformed to the Freundlich isotherm and pseudo-second order kinetics with a high correlation coefficient, R,sup>2 > 0.98. This indicates the Basic Fuchsin adsorbs chemically on the heterogeneous surface of rambutan peel. The maximum adsorption capacity determined from the Langmuir isotherm was 108.696 mg/g. It seems that rambutan peel has the potential to substitute activated carbon as an alternative low-cost adsorbent in the treatment of the dye effluent.
Źródło:
Environment Protection Engineering; 2017, 43, 1; 169-181
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Frothers and gas dispersion: A review of the structure-property-function relationship
Autorzy:
Tan, Y. H.
Finch, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/109942.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
frothers
alcohols
polyglycols
frother structure
mechanisms
Opis:
Over the past 20 years quantitative measures of frother functions have been developed to try to replace such qualitative descriptors as “weak” and “strong”. One of these metrics is the critical coalescence concentration (CCC) that quantifies a frother’s ability to reduce bubble size; another is the concentration at minimum velocity (CMV) that quantifies a frother’s ability to reduce bubble rise velocity. The experimental procedure for the two measures is briefly outlined and the measures are shown to be related. Using CMV, based on more than 50 surfactants from the two main frother families, alcohols and polyglycols, the frother structure-property-function link is investigated. The structure variables were: in alcohols, alkyl chain length, and position of the methyl branch and hydroxyl group(s); and in polyglycols, alkyl chain length, and number of propylene oxide (PO) or ethylene oxide (EO) groups. On the argument that low CMV represents the desired outcome, the main findings are: the dominant effect of alkyl chain length in both alcohols and polyglycols; that for alcohols branched-chain isomers are superior to straight chain, with the best combination being OH at the terminus and the methyl branch as far away as possible; and for polyglycols, PO-based are superior to EO-based. Interpretation of these observations included the effect of structure on the following properties: surface activity, mass transfer rate, H-bonding, and molecule packing.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 1; 40-53
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of temperature fluctuation on the stability of partial nitritation applied for reject water treatment
Autorzy:
Radechovska, H.
Svehla, P.
Radechovsky, J.
Pacek, L.
Balik, J.
Powiązania:
https://bibliotekanauki.pl/articles/207642.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
anammox
nitrifying reactor
ścieki
beztlenowe utlenianie amonu
sekwencyjny reaktor okresowy
reactor nitryfikacyjny
anaerobic ammonium oxidation
sequencing batch reactor
free nitrous acid
rich waste water
oxidizing bacteria
nitrification
Opis:
The influence of sudden and gradual temperature fluctuations on the stability of partial nitritation applied for the treatment of reject water containing ammonium nitrogen (NH4+-N) in the range of 1000 –1400 mg/dm3 was investigated. It was found that a sudden decrease in temperature from 24.3 °C to 14.3 °C and 15.8 °C significantly affected the stability of the process. No negative effect was recorded after a sudden temperature decrease from 24.3 to 17.4 °C. It was also found that during a gradual temperature decrease from 24.3 °C, process stability was negatively affected at 12.7 °C.
Źródło:
Environment Protection Engineering; 2017, 43, 1; 87-99
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of 3D kinematic and electromyographical parameters on cycling economy
Autorzy:
Sinclair, J.
Hebron, J.
Atkinson, S.
Hurst, H.
Taylor, P. J.
Powiązania:
https://bibliotekanauki.pl/articles/306495.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
rower
sport
ekonomia
VO2
cycling
economy
Opis:
Purpose: Economy is considered to be a key factor for the determination of performance in endurance events such as cycling. There have been no investigations which have related cycling economy to simultaneous measurements of 3D kinematics and muscular activation. This study examined selected biomechanical and neuromuscular parameters which have the strongest association with cycling economy. Methods: Twenty-five trained cyclists (31.27±3.19 years) completed steady state cycling time trials at a workload of 180 W. Simultaneous measurements of 3D kinematics and electromyographical parameters were obtained. Continuous measurements of expired gases were used to provide a measure of cycling economy. Results: A multiple regression analysis showed that key parameters of peak knee extension velocity and mean activity of the rectus femoris muscles were significant predictors of VO2 during steady state cycling (P<0.01). Conclusion: This study has documented the key biomechanical parameters pertinent to cycling economy. As economy has been shown to influence aerobic performance, future work should focus on optimising these parameters to improve cycling economy.
Źródło:
Acta of Bioengineering and Biomechanics; 2014, 16, 4; 91-97
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Truncated two-stage compound parabolic concentrator for collecting human diffuse transmission light
Autorzy:
Gao, J.
Han, G.
Lu, Q.
Ding, H.
Xu, J.
Sun, J.
Powiązania:
https://bibliotekanauki.pl/articles/174488.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
optical design
compound parabolic concentrator
CPC
non-imaging optics
near infrared spectroscopy
medicine optical instrument
Opis:
We propose an optical system employing a compound parabolic concentrator for near infrared spectroscope in noninvasive blood components testing. A truncated two-stage compound parabolic concentrator system is designed, which consists of a normal first-stage compound parabolic concentrator and a truncated second-stage compound parabolic concentrator. Using advanced ray tracing technique, the optical efficiencies of truncated two-stage compound parabolic concentrator system, ellipsoidal mirror system and non-optical-focusing mirror system are calculated to be 25.4%, 22.4% and 4.0%, respectively. Furthermore, the total length of truncated two-stage compound parabolic concentrator is only about 68 mm while the ellipsoidal mirror is 110 mm. It indicates that the truncated two-stage compound parabolic concentrator system enhances the ability of concentrating human diffuse transmission light, and it is a benefit to improve signal-to-noise ratio of noninvasive biochemical analysis system efficiently. Due to the advantage of small size, it tends to achieve a miniature instrument.
Źródło:
Optica Applicata; 2018, 48, 2; 325-335
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of cotton on several enzymatic activities of the petroleum contaminated soil. A laboratory experiment
Autorzy:
Jingyan, L.
Jianxiong, W.
Ying, H.
Xianyong, J.
Powiązania:
https://bibliotekanauki.pl/articles/208048.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
cotton
remediation
soil pollution
alkaline phosphatase
degradation of pollutants
enzymatic activities
petroleum-contaminated soil
petroleum-polluted soils
bawełna
rekultywacja
zanieczyszczenie gleby
fosfataza alkaliczna
degradacja zanieczyszczeń
aktywność enzymatyczna
gleba zanieczyszczona ropą naftową
Opis:
A laboratory experiment lasting for 90 days was conducted to examine the interaction between a remediation plant, Gossypium hirsutum, and the petroleum contaminated soil. Root indices and 9 various types of soil enzymatic activities in two separate groups were determined. Results showed that compared to the uncontaminated control, the growth of cotton roots was slightly strengthened at the pollution level of 1000 mg-kg-1, while seriously inhibited at the pollution level of 2000 mg-kg-1 and 4000 mg-kg-1. At the same pollution level, all studied soil enzymatic activities except alkaline phosphatase were markedly higher in the group with plants than in the group without plants which may indicate that the content of nutrients essential for plant growth as well as the activities of microorganisms capable of degrading contaminants were both enhanced in soils planted with cotton, therefore conducive to the increase of the overall fertility level and the degradation of pollutants in the petroleum contaminated soil.
Źródło:
Environment Protection Engineering; 2013, 39, 1; 163-182
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Is bearing resistance negligible during wheelchair locomotion? Design and validation of a testing device
Autorzy:
Bascou, J.
Sauret, Ch.
Lavaste, F.
Pillet, H.
Powiązania:
https://bibliotekanauki.pl/articles/307222.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
wózek inwalidzki
nośność
prędkość obrotowa
wheelchair
bearing resistance
rotation velocity
Opis:
Purpose: Among the different resistances occurring during wheelchair locomotion and that limit the user autonomy, bearing resistance is generally neglected, based on a few studies carried out in static conditions and by manufacturer’s assertion. Therefore, no special attention is generally paid to the mounting and the maintenance of manual wheelchair bearings. However, the effect of inadequate mounting or maintenance on wheelchair bearing resistance has still to be clarified. This study aimed at filling this gap by developing and validating a specific device allowing the measurement of wheelchair bearing friction, characterized by low speed velocities, with an accuracy lower than 0.003 Nm. Methods: The bearing resistance measured by the device was compared to free deceleration measurement, intra and inter operator reproducibility were assessed. A factorial experiment allowed the effects of various functioning parameters (axial and radial loads, velocity) to be classified. Results: The device allowed significant differences in the bearing resistance of static and rotating conditions to be measured, even if a relatively high proportionality was found between both conditions. The factorial experiment allowed the expected impact of the radial load on bearing resistance as well as the predominant effect of the axial load to be demonstrated. Conclusions: As a consequence, it appeared that the control of the axial load is compulsory for measurement purposes or during wheel mounting, to avoid significant increase of global resistance during wheelchair locomotion. The findings of this study could help enhancing the models which assess manual wheelchair mechanical power from its settings and use conditions.
Źródło:
Acta of Bioengineering and Biomechanics; 2017, 19, 3; 165-176
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł

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