Optimizing the Team for Required Power During Track-Cycling Team Pursuit

Purpose: Since the aim of the men’s team pursuit in time-trial track cycling is to accomplish a distance of 4000 m as fast as possible, optimizing aerodynamic drag can contribute to achieving this goal. The aim of this study was to determine the drafting effect in second, third, and fourth position during the team pursuit in track cycling as a function of the team members’ individual frontal areas in order to minimize the required power. Method: Eight experienced track cyclists of the Dutch national selection performed 39 trials of 3 km in different teams of 4 cyclists at a constant velocity of 15.75 m/s. Frontal projected areas were determined, and together with field-derived drag coefficients for all 4 positions, the relationships between frontal areas of team members and drag fractions were estimated using generalized estimating equations. Results: The frontal area of both the cyclist directly in front of the drafter and the drafter himself turned out to be significant determinants of the drag fraction at the drafter’s position (P < .05) for all 3 drafting positions. Predicted required power for individuals in drafting positions differed up to 35 W depending on team composition. For a team, a maximal difference in team efficiency (1.2%) exists by selecting cyclists in a specific sequence. Conclusion: Estimating required power for a specific team composition gives insight into differences in team efficiency for the team pursuit. Furthermore, required power for individual team members ranges substantially depending on team composition.

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The Contingent Effect of Team Composition on the Performance of Entrepreneurial Teams

The Oxford Handbook of Entrepreneurship and Collaboration ◽

10.1093/oxfordhb/9780190633899.013.3 ◽

2019 ◽

pp. 654-680

Author(s):

Serghei Musaji ◽

Julio De Castro

Keyword(s):

Future Research ◽

Team Composition ◽

Team Members ◽

Team Diversity ◽

Entrepreneurial Teams ◽

Knowledge Based ◽

Fertile Ground ◽

Active Debate ◽

And Performance ◽

The Relationship

Despite the continuous interest in studying entrepreneurial teams, the relationship between team composition and, particularly, team diversity and performance remains fertile ground for active debate. Taking roots in the knowledge-based view and organizational learning literatures, this chapter argues that performance in entrepreneurial teams is contingent on (a) the overlap between team members’ knowledge/competences and the content of the performed tasks, (b) the duplication of the team members’ knowledge in the areas with that content, (c) the nature of tasks (exploration or exploitation), (d) the team’s flexibility to adapt to changes in the content and nature of those tasks, and (e) the rate of environmental change. Because an important source of ambiguity in the understanding of how team diversity and performance are linked ties to issues of how team diversity is conceptualized and operationalized, the chapter also proposes a new way of looking at diversity in future research.

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Optimal Team Composition: Diversity to Foster Implicit Team Incentives

Management Science ◽

10.1287/mnsc.2020.3762 ◽

2021 ◽

Author(s):

Jonathan Glover ◽

Eunhee Kim

Keyword(s):

Pay For Performance ◽

Discount Factor ◽

Team Composition ◽

Team Members ◽

Team Culture ◽

Team Design ◽

Functional Teams ◽

Specialized Team ◽

Empirical Implications ◽

Inherent Advantage

We study optimal team design. In our model, a principal assigns either heterogeneous agents to a team (a diverse team) or homogenous agents to a team (a specialized team) to perform repeated team production. We assume that specialized teams exhibit a productive substitutability (e.g., interchangeable efforts with decreasing returns to total effort), whereas diverse teams exhibit a productive complementarity (e.g., cross-functional teams). Diverse teams have an inherent advantage in fostering desirable implicit/relational incentives that team members can provide to each other (tacit cooperation). In contrast, specialization both complicates the provision of cooperative incentives by altering the punishment agents can impose on each other for short expected career horizons and fosters undesirable implicit incentives (tacit collusion) for long expected horizons. As a result, expected compensation is first decreasing and then increasing in the discount factor for specialized teams, while expected compensation is always decreasing in the discount factor for diverse teams. We use our results to develop empirical implications about the association between team tenure and team composition, pay-for-performance sensitivity, and team culture. This paper was accepted by Brian Bushee, accounting.

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Investigation of Influence of Adjustments in Cyclist Arm Position on Aerodynamic Drag Using Computational Fluid Dynamics

Proceedings ◽

10.3390/proceedings2020049159 ◽

2020 ◽

Vol 49 (1) ◽

pp. 159

Author(s):

Knut Erik Teigen Giljarhus ◽

Daniel Årrestad Stave ◽

Luca Oggiano

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Aerodynamic Drag ◽

Time Trial ◽

Elbow Extension ◽

Cfd Simulations ◽

Arm Position ◽

Sport Activities ◽

The Face ◽

Computational Fluid Dynamics Cfd

In professional cycling, even small adjustments in position could mean that valuable seconds are gained over the course of a time-trial race. This study investigates the influence of arm position on the aerodynamic drag of a cyclist. Based on a 3D scanned model of a professional cyclist, 64 alternate positions are generated. The parameters that are investigated are the distance between elbows, elbow extension, and distance between hands. Computational fluid dynamics (CFD) simulations of all positions are performed, and a regression model is built from the results. The results indicate that the optimal posture is achieved for a minimum in all investigated parameters, which means that the hands and elbows should be kept together with hands up towards the face. Furthermore, elbow extension seems to be the most crucial parameter, followed by the distance between elbows, and then by the distance between the hands. The presented methodology can be applied to study other parameters relevant to cycling aerodynamics or be applied to other sport activities as well.

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A wind-tunnel case study: Increasing road cycling velocity by adopting an aerodynamically improved sprint position

Proceedings of the Institution of Mechanical Engineers Part P Journal of Sports Engineering and Technology ◽

10.1177/1754337119866962 ◽

2019 ◽

pp. 175433711986696

Author(s):

Timothy Crouch ◽

Paolo Menaspà ◽

Nathan Barry ◽

Nicholas Brown ◽

Mark C Thompson ◽

...

Keyword(s):

Wind Tunnel ◽

Drag Coefficient ◽

Aerodynamic Drag ◽

Time Trial ◽

Force Measurements ◽

Sampling Errors ◽

Repeated Testing ◽

Road Cycling ◽

Wind Tunnel Study

The main aim of this study was to evaluate the potential to reduce the aerodynamic drag by studying road sprint cyclists’ positions. A male and a female professional road cyclist participated in this wind-tunnel study. Aerodynamic drag measurements are presented for a total of five out-of-seat sprinting positions for each of the athletes under representative competition conditions. The largest reduction in aerodynamic drag measured for each athlete relative to their standard sprinting positions varied between 17% and 27%. The majority of this reduction in aerodynamic drag could be accounted for by changes in the athlete’s projected frontal area. The largest variation in repeat drag coefficient area measurements of out-of-seat sprint positions was 5%, significantly higher than the typical <0.5% observed for repeated testing of time-trial cycling positions. The majority of variation in repeated drag coefficient area measurements was attributed to reproducibility of position and sampling errors associated with time-averaged force measurements of large fluctuating forces.

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Using a Simple Cellular Assay to Map NES Motifs in Cancer-Related Proteins, Gain Insight into CRM1-Mediated NES Export, and Search for NES-Harboring Micropeptides

International Journal of Molecular Sciences ◽

10.3390/ijms21176341 ◽

2020 ◽

Vol 21 (17) ◽

pp. 6341

Author(s):

Maria Sendino ◽

Miren Josu Omaetxebarria ◽

Gorka Prieto ◽

Jose Antonio Rodriguez

Keyword(s):

Nuclear Export ◽

Relevant Information ◽

Sequence Motifs ◽

Specific Sequence ◽

Cellular Assay ◽

Small Proteins ◽

Binding Groove ◽

Related Proteins ◽

Insight Into

The nuclear export receptor CRM1 (XPO1) recognizes and binds specific sequence motifs termed nuclear export signals (NESs) in cargo proteins. About 200 NES motifs have been identified, but over a thousand human proteins are potential CRM1 cargos, and most of their NESs remain to be identified. On the other hand, the interaction of NES peptides with the “NES-binding groove” of CRM1 was studied in detail using structural and biochemical analyses, but a better understanding of CRM1 function requires further investigation of how the results from these in vitro studies translate into actual NES export in a cellular context. Here we show that a simple cellular assay, based on a recently described reporter (SRVB/A), can be applied to identify novel potential NESs motifs, and to obtain relevant information on different aspects of CRM1-mediated NES export. Using cellular assays, we first map 19 new sequence motifs with nuclear export activity in 14 cancer-related proteins that are potential CRM1 cargos. Next, we investigate the effect of mutations in individual NES-binding groove residues, providing further insight into CRM1-mediated NES export. Finally, we extend the search for CRM1-dependent NESs to a recently uncovered, but potentially vast, set of small proteins called micropeptides. By doing so, we report the first NES-harboring human micropeptides.

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Modeling the Effect of a Prosthetic Limb on 4-km Pursuit Performance

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2013-0519 ◽

2015 ◽

Vol 10 (1) ◽

pp. 3-10 ◽

Cited By ~ 7

Author(s):

W. Lee Childers ◽

Tim P. Gallagher ◽

J. Chad Duncan ◽

Douglas K. Taylor

Keyword(s):

Aerodynamic Drag ◽

Time Trial ◽

Monte Carlo Analysis ◽

Aerodynamic Design ◽

Practical Application ◽

Integration Model ◽

Cycling Time Trial ◽

Prosthetic Limb ◽

The Individual ◽

Forward Integration

The individual pursuit is a 4-km cycling time trial performed on a velodrome. Parathletes with transtibial amputation (TTA) have lost physiological systems, but this may be offset by the reduced aerodynamic drag of the prosthesis. This research was performed to understand the effect of a unilateral TTA on Olympic 4-km pursuit performance. A forward-integration model of pursuit performance explored the interplay between power loss and aerodynamic gains in parathletes with TTA. The model is calibrated to a 4-km pursuit time of 4:10.5 (baseline), then adjusted to account for a TTA. Conditions simulated were based on typical pedal asymmetry in TTA (AMP), if foot stiffness were decreased (FLEX), if pedaling asymmetries were minimized (ASYM), if the prosthesis were aerodynamically optimized (AERO), if the prosthesis had a cosmetic cover (CC), and if all variables were optimized (OPT). A random Monte Carlo analysis was performed to understand model precision. Four-kilometer pursuit performances predicted by the model were 4:10.5, 4:20.4, 4:27.7, 4:09.2, 4:19.4, 4:27.9, and 4:08.2 for the baseline, AMP, FLEX, ASYM, AERO, CC, and OPT models, respectively. Model precision was ±3.7 s. While the modeled time decreased for ASYM and OPT modeled conditions, the time reduction fell within model precision and therefore was not significant. Practical application of these results suggests that parathletes with a TTA could improve performance by minimizing pedaling asymmetry and/or optimizing aerodynamic design, but, at best, they will have performance similar to that of intact cyclists. In conclusion, parathletes with TTA do not have a net advantage in the individual pursuit.

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Predicting Time Trial Performance Using Field Measures Of The Bicycle-rider Aerodynamic Drag

Medicine & Science in Sports & Exercise ◽

10.1249/00005768-200505001-02105 ◽

2005 ◽

Vol 37 (Supplement) ◽

pp. S408

Author(s):

Allen C. Lim ◽

Andy G. Edwards ◽

Ryan N. Ignatz ◽

Ben E. Birken ◽

William C. Byrnes

Keyword(s):

Aerodynamic Drag ◽

Time Trial ◽

Time Trial Performance ◽

Bicycle Rider ◽

Trial Performance

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621 PB 331 A FRUIT TREE COOLING CONTROL SYSTEM SIMULATOR

HortScience ◽

10.21273/hortsci.29.5.521c ◽

1994 ◽

Vol 29 (5) ◽

pp. 521c-521

Author(s):

Matthew Rogoyski ◽

Alvan Gaus ◽

Byron McNew ◽

Israel Broner ◽

Thomas Mourney

Keyword(s):

Control System ◽

Cooling System ◽

System Development ◽

Object Oriented ◽

Team Members ◽

C Programming Language ◽

The Past ◽

C Programming ◽

Object Oriented Approach ◽

Insight Into

A simulator of a control system for evaporative cooling of crop canopies was developed. This development, prior to implementation of an irrigation/cooling system, allowed for experimentation before committing resources to the field system. The project provided insight into problems of modeling interaction between biological, mechanical, and digital systems and demonstrated how specialists from diverse areas can solve these problems. The object orientation methodology and the C++ programming language were tools for development of this simulator. A communication mechanism was devised to facilitate interactions between software entities representing both concrete and abstract objects corresponding to the problem domain. The object-oriented approach to the system development allowed for better communication between team members, irrespective of their background in software engineering. The modular and polymorphic nature of the object-oriented code made it possible to plan for code reuse in future projects. Simulator development using the object-oriented paradigm was found to be preferable over the procedural model used by team members in other projects in the past.

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627 Trauma & Orthopaedic National Selection – What Is Really Going Through the Mind of Applicants?

British Journal of Surgery ◽

10.1093/bjs/znab259.1000 ◽

2021 ◽

Vol 108 (Supplement_6) ◽

Author(s):

A Curtis

Keyword(s):

Junior Doctors ◽

Core Knowledge ◽

Selection Interview ◽

National Selection ◽

National Training ◽

The Uk ◽

Almost All ◽

The Mind ◽

First Time ◽

Insight Into

Abstract Aim Obtaining a training number in Trauma & Orthopaedics (T&O) remains highly competitive. This study aims to provide an insight into applicant’s perceptions and preparation for the T&O national selection interview. Method 162 junior doctors applying to T&O national selection in 2021 were sent questionnaires using SurveyMonkey in December 2020. Applicants were identified from those attending the annual OrthoRevision ‘ST3 Core Knowledge Interview Course’. In total, 74 junior doctors (45.7%) covering all 16 surgical training regions in the UK completed feedback. Results There were wide variations in how much applicants would spend on preparation for the interview (e.g., books, revision websites, courses): 45.9% spend £100 - £500; 21.6% spend £500-£1,000; and 6.8% spend >£1,000. Most start preparation 3 months prior to the interview (42.5%) with the preferred method being practice with colleagues (49.3%). Almost all candidates (80.2%) use the ‘OrthoInterview’ question bank. Free mock interview courses were only available to 27% with candidates strongly in favour (78%) of the study budget covering preparatory courses in addition to study leave being granted to attend these courses (86%). At the first attempt at obtaining a training number, 69.9% were selective about where they would accept a job; in subsequent years candidates would be more willing to accept a job in any deanery (40.3%). Conclusions For the first time, we present the perceptions of applicants to T&O national training in the UK. Many candidates dedicate a large amount of time and money to the process and are initially more selective about where they apply.

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