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1.
Minim Invasive Ther Allied Technol ; 33(2): 120-128, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38146672

RESUMO

The mechanical properties of the stent graft are important factors influencing the outcome of TEVAR treatment and the occurrence of postoperative complications. The aim of this study is to improve and design a mechanical performance testing equipment for thoracic aortic stent grafts. The mechanical performance testing equipment consists of a radial force testing equipment of the stent graft designed by the wire compression grip method and a dynamic straightening force testing device with stable and controllable test conditions and continuously variable test angles. By constructing the testing equipment to physically measure the stent specimen, the experimental results reflect the trend of change and the simulation results are basically consistent, i.e. the mechanical properties of the thoracic aortic stent designed in this study is feasible and the measured data are valid. The testing equipment can provide the basis and reference direction for the quality testing of stent graft products, optimisation of mechanical properties of stent grafts and R&D innovation.


Assuntos
Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Prótese Vascular , Desenho de Prótese , Aorta Torácica/cirurgia , Stents , Aneurisma da Aorta Torácica/cirurgia , Resultado do Tratamento
2.
Eur J Appl Physiol ; 123(6): 1215-1227, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36763121

RESUMO

PURPOSE: A cyclist's rate of force/torque development (RFD/RTD) and peak force/torque can be measured during single-joint or whole-body isometric tests, or during cycling. However, there is limited understanding of the relationship between these measures, and of the mechanisms that contribute to each measure. Therefore, we examined the: (i) relationship between quadriceps central and peripheral neuromuscular function with RFD/RTD in isometric knee extension, isometric mid-thigh pull (IMTP), and sprint cycling; and (ii) relationship among RFD/RTD and peak force/torque between protocols. METHODS: Eighteen trained cyclists completed two familiarisation and two experimental sessions. Each session involved an isometric knee extension, IMTP, and sprint cycling protocol, where peak force/torque, average and peak RFD/RTD, and early (0-100 ms) and late (0-200 ms) RFD/RTD were measured. Additionally, measures of quadriceps central and peripheral neuromuscular function were assessed during the knee extension. RESULTS: Strong relationships were observed between quadriceps early EMG activity (EMG50/M) and knee extension RTD (r or ρ = 0.51-0.65) and IMTP late RFD (r = 0.51), and between cycling early or late RTD and peak twitch torque (r or ρ = 0.70-0.75). Strong-to-very strong relationships were observed between knee extension, IMTP, and sprint cycling for peak force/torque, early and late RFD/RTD, and peak RFD/RTD (r or ρ = 0.59-0.80). CONCLUSION: In trained cyclists, knee extension RTD or IMTP late RFD are related to measures of quadriceps central neuromuscular function, while cycling RTD is related to measures of quadriceps peripheral neuromuscular function. Further, the strong associations among force/torque measures between tasks indicate a level of transferability across tasks.


Assuntos
Contração Isométrica , Força Muscular , Humanos , Torque , Músculo Quadríceps , Articulação do Joelho
3.
Sensors (Basel) ; 23(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37430569

RESUMO

Hallux strength is associated with sports performance and balance across the lifespan, and independently predicts falls in older adults. In rehabilitation, Medical Research Council (MRC) Manual Muscle Testing (MMT) is the clinical standard for hallux strength assessment, but subtle weakness and longitudinal changes in strength may go undetected. To address the need for research-grade yet clinically feasible options, we designed a new load cell device and testing protocol to Quantify Hallux Extension strength (QuHalEx). We aim to describe the device, protocol and initial validation. In benchtop testing, we used eight precision weights to apply known loads from 9.81 to 78.5 N. In healthy adults, we performed three maximal isometric tests for hallux extension and flexion on the right and left sides. We calculated the Intraclass Correlation Coefficient (ICC) with 95% confidence interval and descriptively compared our isometric force-time output to published parameters. QuHalEx benchtop absolute error ranged from 0.02 to 0.41 (mean 0.14) N. Benchtop and human intrasession output was repeatable (ICC 0.90-1.00, p < 0.001). Hallux strength in our sample (n = 38, age 33.5 ± 9.6 years, 53% female, 55% white) ranged from 23.1 to 82.0 N peak extension force and 32.0 to 142.4 N peak flexion, and differences of ~10 N (15%) between toes of the same MRC grade (5) suggest that QuHalEx is able to detect subtle weakness and interlimb asymmetries that are missed by MMT. Our results support ongoing QuHalEx validation and device refinement with a longer-term goal of widespread clinical and research application.


Assuntos
Desempenho Atlético , Hallux , Feminino , Humanos , Idoso , Adulto Jovem , Adulto , Masculino , Dedos do Pé , Extremidade Inferior , Longevidade
4.
Sensors (Basel) ; 23(14)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37514603

RESUMO

Steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) systems have been extensively researched over the past two decades, and multiple sets of standard datasets have been published and widely used. However, there are differences in sample distribution and collection equipment across different datasets, and there is a lack of a unified evaluation method. Most new SSVEP decoding algorithms are tested based on self-collected data or offline performance verification using one or two previous datasets, which can lead to performance differences when used in actual application scenarios. To address these issues, this paper proposed a SSVEP dataset evaluation method and analyzed six datasets with frequency and phase modulation paradigms to form an SSVEP algorithm evaluation dataset system. Finally, based on the above datasets, performance tests were carried out on the four existing SSVEP decoding algorithms. The findings reveal that the performance of the same algorithm varies significantly when tested on diverse datasets. Substantial performance variations were observed among subjects, ranging from the best-performing to the worst-performing. The above results demonstrate that the SSVEP dataset evaluation method can integrate six datasets to form a SSVEP algorithm performance testing dataset system. This system can test and verify the SSVEP decoding algorithm from different perspectives such as different subjects, different environments, and different equipment, which is helpful for the research of new SSVEP decoding algorithms and has significant reference value for other BCI application fields.


Assuntos
Interfaces Cérebro-Computador , Potenciais Evocados Visuais , Humanos , Eletroencefalografia/métodos , Estimulação Luminosa , Algoritmos
5.
Sensors (Basel) ; 22(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35746297

RESUMO

Pedestrian routing is important in a multitude of public spaces, especially those characterized by a large number of newcomers. Their needs may be diverse, with priority for the shortest path, the less crowded or the less polluted one, the accessibility for reduced mobility, or the sheltering from unfavorable weather conditions. Hence, typical graph-based routing must be enriched to support multiple policies, at the choice of each person. The paper proposes a systemic approach and a set of services for orientation and accessibility, which are both community-driven and data-driven, for correctly perceiving the routing necessities and the surrounding situation. The response time to a pathfinding query depends on the types of policies applied and not only on their number, because each of them contributes to the customization of the weighted graph, although it refers to the same physical space traversed by pedestrians. The paper also presents results of loading tests for up to 5000 Virtual Users, inspired from real-life requirements and executed on a graph that models a real building in our university; different policies are applied to assess performance metrics, with simulated community feedback and sensor data.


Assuntos
Pedestres , Humanos , Políticas , Tempo (Meteorologia)
6.
Sensors (Basel) ; 22(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35161745

RESUMO

The use of monitoring systems based on cloud computing has become common for smart buildings. However, the dilemma of centralization versus decentralization, in terms of gathering information and making the right decisions based on it, remains. Performance, dependent on the system design, does matter for emergency detection, where response time and loading behavior become very important. We studied several design options based on edge computing and containers for a smart building monitoring system that sends alerts to the responsible personnel when necessary. The study evaluated performance, including a qualitative analysis and load testing, for our experimental settings. From 700+ edge nodes, we obtained response times that were 30% lower for the public cloud versus the local solution. For up to 100 edge nodes, the values were better for the latter, and in between, they were rather similar. Based on an interpretation of the results, we developed recommendations for five real-world configurations, and we present the design choices adopted in our development for a complex of smart buildings.


Assuntos
Computação em Nuvem , Computadores , Monitorização Fisiológica
7.
Sensors (Basel) ; 22(11)2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35684899

RESUMO

The application of direct current (DC) produces a rapid and reversible nerve conduction block. However, prolonged injection of charge through a smooth platinum electrode has been found to cause damage to nervous tissue. This damage can be mitigated by incorporating high-capacitance materials (HCM) (e.g., activated carbon or platinum black) into electrode designs. HCMs increase the storage charge capacity (i.e., "Q value") of capacitive devices. However, consecutive use of these HCM electrodes degrades their surface. This paper evaluates activated carbon and platinum black (PtB) electrode designs in vitro to determine the design parameters which improve surface stability of the HCMs. Electrode designs with activated carbon and PtB concentrations were stressed using soak, bend and vibration testing to simulate destructive in vivo environments. A Q value decrease represented the decreased stability of the electrode-HCM interface. Soak test results supported the long-term Q value stabilization (mean = 44.3 days) of HCM electrodes, and both HCMs displayed unique Q value changes in response to soaking. HCM material choices, Carbon Ink volume, and application of Nafion™ affected an electrode's ability to resist Q value degradation. These results will contribute to future developments of HCM electrodes designed for extended DC application for in vivo nerve conduction block.


Assuntos
Carvão Vegetal , Platina , Capacitância Elétrica , Eletricidade , Eletrodos
8.
Sensors (Basel) ; 22(7)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35408242

RESUMO

Research on the stress state of rock mass is essential for revealing the distribution characteristics and evolution law of the surrounding rock stress field in the roadway, studying the coal-rock dynamic disaster and the design of roadway support. This thesis proposes a three-dimensional stress monitoring method for surrounding rocks based on fiber Bragg grating (FBG) sensing technology and a cube-shaped three-dimensional stress fiber grating sensor is developed based on the principle of this monitoring method. According to the fiber grating strain obtained by numerical simulation, the calculated three-dimensional stress value is basically consistent with the theoretical value. The margin of error was plus or minus one percentage point. The sensing performance of the sensor was tested using a uniaxial compression experiment instead of a triaxial compression experiment. The experimental results show that in the range of 0~50 Mpa, the sensor's sensitivity to X, Y and Z axis stress is 25.51, 25.97 and 24.86 pm/Mpa, respectively. The relative error of measured stress is less than 4%. Meanwhile, the sensor has good linearity and repeatability, and has broad application prospects in the field of underground engineering safety monitoring such as in coal mines and tunnels.

9.
Arch Orthop Trauma Surg ; 142(7): 1337-1349, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33484315

RESUMO

INTRODUCTION: Various impairments such as soleus atrophy and consecutive functional deficits in end-range plantarflexion have been described in surgical repair of acute Achilles tendon rupture. The aim of this study was to assess the functional performance at midterm following open surgical repair. MATERIALS AND METHODS: This cross-sectional study includes n = 52 patients which were tested on average 3.5 ± 1.4 years postoperatively using three different functional performance tests and patient-reported outcome measures. Two different surgical techniques (anatomical repair = AR vs. conventional repair = CR) were compared in a subanalysis. The testing included isokinetic strength testing, a novel setup of heel-rise testing using a marker-based 3D motion analysis system and a gait analysis. RESULTS: At an average 3.5 years post-surgery, there is a persisting deficit in plantarflexion strength of 10.2%. Moreover, analysis of maximum peak torque angle and strength deficits according to the plantarflexion angle revealed that these deficits are not equally distributed across the range of motion. AR results in a significantly smaller deficit at 10° of plantarflexion compared to CR (13.9 vs. 29.9%, p < 0.05). This reflects into the functional performance during different modalities (static vs. dynamic) in this novel method of heel-rise testing. CONCLUSION: In summary, there are persisting functional deficits at > 3 years following Achilles tendon repair which range from strength deficits to specific impairments of functional performance e.g. during heel rise. Anatomical reconstruction is associated with an improved functional performance potentially due to a more symmetric strength during end-range plantarflexion which transfers into a higher satisfaction during athletic activities. LEVEL OF EVIDENCE: III, retrospective cohort study.


Assuntos
Tendão do Calcâneo , Traumatismos do Tornozelo , Traumatismos dos Tendões , Tendão do Calcâneo/cirurgia , Estudos Transversais , Humanos , Desempenho Físico Funcional , Estudos Retrospectivos , Ruptura/cirurgia , Traumatismos dos Tendões/cirurgia , Resultado do Tratamento
10.
J Sports Sci Med ; 21(1): 131-136, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35250343

RESUMO

Accurate assessment of peak rowing power is crucial for rowing-specific performance testing. Therefore, within and between day reliability of a non-modified rowing ergometer was examined. 52 trained male rowers (21.0 ± 2.9 years; 1.89 ± 0.05 m; 83.2 ± 8.2 kg; 2,000-m ergometer Time Trial mean power: 369 ± 57 W) performed (two times 4) isolated concentric rowing strokes (DRIVE) and single flexion-extension cycle (FEC-type) rowing strokes (SLIDE-DRIVE) on two separate days (1 week apart). Good to excellent intraclass correlation coefficients (0.94 ≤ ICC ≤ 1.00), low standard error of measurement (≤ 2.7%), low coefficient of variation (≤ 4.9%), and suitable level of agreements (≤ 30W) for DRIVE and SLIDE-DRIVE indicated a high level of (within and between day) reliability. In addition, SLIDE-DRIVE (423 ± 157 W) revealed remarkably higher rowing power (p ≤ 0.001; ηp2 = 0.601; SMD = 0.34) compared to DRIVE (370 ± 154 W). The non-modified rowing ergometer is considered to be a reliable tool for the peak power assessment during isolated concentric contraction and FEC-type rowing strokes. Notably higher power outputs (compared to an isolated concentric contraction) during FEC rowing may refer to an underlying stretch shortening cycle.


Assuntos
Ergometria , Esportes Aquáticos , Humanos , Masculino , Reprodutibilidade dos Testes
11.
Knee Surg Sports Traumatol Arthrosc ; 29(8): 2517-2527, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33660053

RESUMO

PURPOSE: To assess whether the neuromuscular activation pattern following Achilles tendon rupture and repair may contributes to the observable functional deficits in this severe and increasingly frequent injury. METHODS: In this study, the neuromuscular activation using surface EMG of n = 52 patients was assessed during a battery of functional performance tasks to assess potential alterations of muscular activation and recruitment. We analyzed the injured leg vs. the contralateral healthy leg at a mean of 3.5 years following open surgical repair. The testing battery included isokinetic strength testing, bipedal and single-legged heel-rise testing as well as gait analysis. RESULTS: During isokinetic testing, we observed a higher activation integral for all triceps surae muscles of the injured side during active dorsiflexion, e.g., eccentric loading on the injured leg, while concentric plantarflexion showed no significant difference. Dynamic heel-rise testing showed a higher activation in concentric and eccentric loading for all posterior muscles on the injured side (not significant); while static heel-rise for 10 sec. revealed a significantly higher activation. Further analysis of frequency of fast Fourier-transformed EMG revealed a significantly higher median frequency in the injured leg. Gait analysis revealed a higher pre-activation of the tibialis anterior before ground contact, while medial and lateral gastrocnemius muscles of the injured leg showed a significantly higher activation during push-off phase. CONCLUSIONS: The results of this study provide evidence on the neuromuscular changes 3.5 years following open surgical Achilles tendon repair. These complex neuromuscular changes are manifested to produce the maximum force output whilst protecting the previously injured tendon. The observed alterations may be related to an increased recruitment of type II muscle fibers which could make the muscles prone to fatigue. LEVEL OF EVIDENCE: III.


Assuntos
Tendão do Calcâneo , Traumatismos dos Tendões , Tendão do Calcâneo/cirurgia , Humanos , Perna (Membro) , Músculo Esquelético , Ruptura/cirurgia , Traumatismos dos Tendões/cirurgia
12.
J Occup Environ Hyg ; 18(2): 51-64, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33412086

RESUMO

The Two-Zone model is used in occupational hygiene to predict both near-field and far-field airborne contaminant concentrations. A literature review was carried out on 21 scientific publications in which the Two-Zone model was used to assess occupational exposure to solvent vapors. Data on exposure scenarios, solvents, generation/emission rates, near- and far-field parameters, and model performance were collected and analyzed. Over the 24 exposure scenarios identified, 18 were evaluated under controlled conditions, 5 under normal workplace activities, and 1 was reported based on literature data. The scenarios involved a variety of tasks which consisted, mostly, of cleaning metal parts, spraying solvents onto surfaces, spilling liquids, and filling containers with volatile substances. Twenty-eight different solvents were modeled and the most commonly tested were benzene, toluene, and acetone. Emission rates were considered constant in 16 scenarios, exponentially decreasing in 6 scenarios, and intermittent in 2 scenarios. Four-hundred-and-forty-six (446) predicted-to-measured concentration ratios were calculated across the 21 studies; 441 were obtained in controlled conditions, 4 under normal workplace activities, and 1 was calculated based on the literature data. For controlled studies, the Two-Zone model predictive performance was within a factor of 0.3-3.7 times the measured concentrations with 93% of the values between 0.5 and 2. The model overestimated the measured concentrations in 63% of the evaluations. The median predicted concentration for the near-field was 1.38 vs. 1.02 for the far-field. Results suggest that the model might be a useful tool for predicting occupational exposure to vapors of solvents by providing a conservative approach. Harmonization in model testing strategies and data presentation is needed in future studies to improve the assessment of the predictability of the Two-Zone model. Moreover, this review has provided a database of exposure scenarios, input parameter values, and model predictive performances which can be useful to occupational hygienists in their future modeling activities.


Assuntos
Poluentes Ocupacionais do Ar , Exposição Ocupacional , Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental , Modelos Teóricos , Exposição Ocupacional/análise , Solventes/análise
13.
Empir Softw Eng ; 26(6): 133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34776757

RESUMO

Regression testing comprises techniques which are applied during software evolution to uncover faults effectively and efficiently. While regression testing is widely studied for functional tests, performance regression testing, e.g., with software microbenchmarks, is hardly investigated. Applying test case prioritization (TCP), a regression testing technique, to software microbenchmarks may help capturing large performance regressions sooner upon new versions. This may especially be beneficial for microbenchmark suites, because they take considerably longer to execute than unit test suites. However, it is unclear whether traditional unit testing TCP techniques work equally well for software microbenchmarks. In this paper, we empirically study coverage-based TCP techniques, employing total and additional greedy strategies, applied to software microbenchmarks along multiple parameterization dimensions, leading to 54 unique technique instantiations. We find that TCP techniques have a mean APFD-P (average percentage of fault-detection on performance) effectiveness between 0.54 and 0.71 and are able to capture the three largest performance changes after executing 29% to 66% of the whole microbenchmark suite. Our efficiency analysis reveals that the runtime overhead of TCP varies considerably depending on the exact parameterization. The most effective technique has an overhead of 11% of the total microbenchmark suite execution time, making TCP a viable option for performance regression testing. The results demonstrate that the total strategy is superior to the additional strategy. Finally, dynamic-coverage techniques should be favored over static-coverage techniques due to their acceptable analysis overhead; however, in settings where the time for prioritzation is limited, static-coverage techniques provide an attractive alternative.

14.
Arch Orthop Trauma Surg ; 140(6): 751-760, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31996981

RESUMO

INTRODUCTION: Ruptures of the anterior cruciate ligament (ACL) can be accompanied by meniscal lesions. Generally, the rehabilitation protocols are altered by meniscal repair. Therefore, the aim of this study was to investigate the effect of meniscal repair on the early recovery of thigh muscle strength in ACL reconstruction (ACLR). MATERIALS AND METHODS: We performed a matched cohort analysis of n = 122 isolated ACLR (CON) compared to n = 61 ACLR with meniscal repair (ACLR + MR). The subgroups of meniscal repair consisted of 30 patients who had undergone medial meniscus repairs (MM), 19 lateral meniscus repairs (LM) and 12 repairs of medial and lateral meniscus (BM). Isokinetic strength measurement was performed pre-operatively and 6 months post-surgery to perform a cross-sectional and a longitudinal analysis. All injuries were unilateral, and the outcome measures were compared to the non-affected contralateral leg. RESULTS: Six months postoperatively overall there is no significant difference between the groups (extension strength MR 82% vs. CON 85% and flexion strength 86% vs. 88%, resp.). Subgroup analysis showed that medial repairs exhibit a comparable leg symmetry while lateral repairs performed worse with leg symmetry being 76% in extension and 81% in flexion strength. Patients undergoing BM repair performed in between lateral and medial repairs (82% extension, 86% flexion). CONCLUSION: Generally, meniscal repair in conjunction with ACLR does not significantly alter the recovery of limb symmetry in strength at 6 months postoperatively. Interestingly, medial repairs seem to perform superior to lateral meniscal repair and repair of both menisci. Since the recovery of symmetric strength is a major factor in rehabilitation testing, these results will help to advise surgeons on appropriate rehabilitation protocols and setting realistic goals for the injured athlete. LEVEL OF EVIDENCE: III, retrospective cohort study.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior , Meniscos Tibiais/cirurgia , Força Muscular/fisiologia , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Reconstrução do Ligamento Cruzado Anterior/estatística & dados numéricos , Humanos , Extremidade Inferior , Estudos Retrospectivos , Resultado do Tratamento
15.
Vet Clin North Am Equine Pract ; 36(2): 211-234, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32534857

RESUMO

Genetic testing in horses began in the 1960s, when parentage testing using blood group markers became the standard. In the 1990s, parentage testing shifted from evaluating blood groups to DNA testing. The development of genetics and genomics in both human and veterinarian medicine, along with continued technological advances in the last 2 decades, has helped unravel the causal variants for many horse traits. Genetic testing is also now possible for a variety of phenotypic and disease traits and is used to assist in breeding and clinical management decisions. This article describes the genetic tests that are currently available for horses.


Assuntos
Testes Genéticos/veterinária , Cavalos/genética , Animais , Cruzamento/métodos , Doenças dos Cavalos/genética
16.
J Sports Sci ; 36(4): 445-450, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28406356

RESUMO

This study investigated the associations between fundamental athletic movement and physical fitness in junior Australian football (AF). Forty-four under 18 players performed a fundamental athletic movement assessment consisting of an overhead squat, double lunge, single leg Romanian deadlift and a push up. Movements were scored on three assessment criterions using a three-point scale. Additionally, participants performed five physical fitness tests commonly used for talent identification in AF. A Spearman's nonparametric correlation matrix was built, with correlation coefficients being visualised using a circularly rendered correlogram. Score on the overhead squat was moderately positively associated with dynamic vertical jump height on left (rs = 0.40; P ≤ 0.05) and right (rs = 0.30; P ≤ 0.05) leg take-off, stationary vertical jump (rs = 0.32; P ≤ 0.05) and negatively associated with 20-m sprint time (rs = -0.35; P ≤ 0.05). Score on the double lunge (left/right side) was moderately positively associated with the same physical fitness tests as well as score on the multistage fitness test. Results suggest that improvements in physical fitness qualities may occur through concurrent increases in fundamental athletic movement skill, namely the overhead squat and double lunge movements. These findings may assist with the identification and development of talent.


Assuntos
Aptidão/fisiologia , Destreza Motora/fisiologia , Aptidão Física/fisiologia , Futebol/fisiologia , Adolescente , Austrália , Estudos Transversais , Teste de Esforço , Humanos , Movimento
17.
IEEE Trans Robot ; 34(2)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38606005

RESUMO

Force-based manipulation control strategies are evolving as a primary mechanism in robotics for performing the fine manipulation tasks typical within manufacturing assembly. The ability to systematically compare robotic system performance and quantify true advancement in fine manipulation is of utmost importance. Accordingly, the objectives of this paper are threefold: 1) creation of a peg-in-hole test method with associated performance metrics and a systematic data analysis strategy for performance benchmarking, 2) first demonstration of a recently developed manipulation controller piloting a robotic hand and its paired task-level logic for completing the peg-in-hole test, and 3) exemplifying the performance benchmarking technique by comparing two approaches for robotic insertions-the previously mentioned compliant hand, stiff arm system, and a stiff gripper, compliant arm system. Analyses reveal that the unconventional hand system can perform at and sometimes above the level of the gripper system in the developed peg-in-hole scenario. Moreover, the hand's active control of the peg's full Cartesian pose reduces positional error sensitivity and minimizes exerted insertion forces, highlighting the strategy's potential for fine manipulation tasks. Results indicate that robotic arms equipped with highly articulated and sensorized robotic hands can provide a truly realizable solution path for performing peg-in-hole tasks.

18.
J Sports Sci ; 34(14): 1340-5, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26862858

RESUMO

This study investigated whether a multi-dimensional assessment could assist with talent identification in junior Australian football (AF). Participants were recruited from an elite under 18 (U18) AF competition and classified into two groups; talent identified (State U18 Academy representatives; n = 42; 17.6 ± 0.4 y) and non-talent identified (non-State U18 Academy representatives; n = 42; 17.4 ± 0.5 y). Both groups completed a multi-dimensional assessment, which consisted of physical (standing height, dynamic vertical jump height and 20 m multistage fitness test), technical (kicking and handballing tests) and perceptual-cognitive (video decision-making task) performance outcome tests. A multivariate analysis of variance tested the main effect of status on the test criterions, whilst a receiver operating characteristic curve assessed the discrimination provided from the full assessment. The talent identified players outperformed their non-talent identified peers in each test (P < 0.05). The receiver operating characteristic curve reflected near perfect discrimination (AUC = 95.4%), correctly classifying 95% and 86% of the talent identified and non-talent identified participants, respectively. When compared to single assessment approaches, this multi-dimensional assessment reflects a more comprehensive means of talent identification in AF. This study further highlights the importance of assessing multi-dimensional performance qualities when identifying talented team sports.


Assuntos
Aptidão , Estatura , Teste de Esforço/métodos , Destreza Motora , Futebol , Adolescente , Austrália , Humanos , Masculino , Análise e Desempenho de Tarefas
19.
J Equine Sci ; 27(4): 131-142, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27974872

RESUMO

The history of research on the exercise physiology of racehorses in Japan dates back to the 1930s. A research report entitled "Studies on exercise physiology and performance testing of the racehorse", published in 1933 by Shigeo Matsuba and Torao Shimamura of The University of Tokyo, was epoch-making and the most important study in the history of equine exercise physiology in Japan. Research results were reported from 92 Thoroughbred racehorses in a large-scale project during the period of 1928 to 1932 at the Shimofusa Imperial Farm and the Koiwai Farm, which were the two greatest racehorse farms at that time. A total of 20 physiological variables were measured to evaluate the fitness of Thoroughbred racehorses before exercise (Pre), just after exercise (Post), 1 hr after exercise (1 hr), 2 hr after exercise (2 hr), and 3 hr after exercise (3 hr) in order to calculate their recovery rates as an index of fitness and performance. The percentage of the Pre value at 1 hr, 2 hr, and 3 hr was calculated. When the percentage of a variable reached 95-105% of the Pre value, the variable was considered to be recovered. The percentage of the total number of variables that were recovered for each time period was calculated, and an overall average was calculated from them; Matsuba and Shimamura proposed calling this overall average the "recovery rate", which could then be applied to evaluate each horse. The effects of training on racehorses were subsequently evaluated by measuring the various physiological variables and the recovery rate.

20.
Public Health Nutr ; 18(12): 2126-34, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25529170

RESUMO

OBJECTIVE: The present research was an experimental test that aimed to quantify the impact of two dominant front-of-pack (FOP) nutritional label formats on consumer evaluations of food products that carried them. The two FOP label types tested were the traffic light label and the Percentage Daily Intake. DESIGN: A 4×5 partially replicated Latin square design was used that allowed the impact of the FOP labels to be isolated from the effects of the product and the consumers who were performing the evaluations. SETTING: The experiment was conducted on campus at the University of Otago, New Zealand. SUBJECTS: The participants were 250 university students selected at random who met qualifying criteria of independent living and regular purchase of the products used in the research. They were not aware of the purpose of the research. RESULTS: The presence of FOP labels led to significant and positive changes in consumer purchase intentions towards the products that carried them. These changes were not affected by the nature of FOP labels used, their size or the product nutritional status (good/bad) that they were reporting. CONCLUSIONS: The result is consistent with the participants paying attention to the FOP label and then using it as an adimensional cue indicating product desirability. As such, it represents a complete functional failure of both of these FOP label types in this specific instance. This result supports calls for further research on the performance of these FOP labels before any move to compulsory deployment is made.


Assuntos
Comportamento de Escolha , Comportamento do Consumidor , Rotulagem de Alimentos/métodos , Adolescente , Adulto , Feminino , Preferências Alimentares , Humanos , Masculino , Nova Zelândia , Projetos Piloto , Adulto Jovem
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