Mechanical power output is a key performance-determining variable in many cyclic sports. In rowing, instantaneous power output is commonly determined as the dot product of handle force moment and oar angular velocity. The aim of this study was to show that this commonly used proxy is theoretically flawed and to provide an indication of the magnitude of the error. To obtain a consistent dataset, simulations were performed using a previously proposed forward dynamical model. Inputs were previously recorded rower kinematics and horizontal oar angle, at 20 and 32 strokes∙min−1. From simulation outputs, true power output and power output according to the common proxy were calculated. The error when using the common proxy was quantified as the difference between the average power output according to the proxy and the true average power output (P̅residual), and as the ratio of this difference to the true average power output (ratiores./rower). At stroke rate 20, P̅residual was 27.4 W and ratiores./rower was 0.143; at stroke rate 32, P̅residual was 44.3 W and ratiores./rower was 0.142. Power output in rowing appears to be underestimated when calculated according to the common proxy. Simulations suggest this error to be at least 10% of the true power output.
DOCUMENT
The security of online assessments is a major concern due to widespread cheating. One common form of cheating is impersonation, where students invite unauthorized persons to take assessments on their behalf. Several techniques exist to handle impersonation. Some researchers recommend use of integrity policy, but communicating the policy effectively to the students is a challenge. Others propose authentication methods like, password and fingerprint; they offer initial authentication but are vulnerable thereafter. Face recognition offers post-login authentication but necessitates additional hardware. Keystroke Dynamics (KD) has been used to provide post-login authentication without any additional hardware, but its use is limited to subjective assessment. In this work, we address impersonation in assessments with Multiple Choice Questions (MCQ). Our approach combines two key strategies: reinforcement of integrity policy for prevention, and keystroke-based random authentication for detection of impersonation. To the best of our knowledge, it is the first attempt to use keystroke dynamics for post-login authentication in the context of MCQ. We improve an online quiz tool for the data collection suited to our needs and use feature engineering to address the challenge of high-dimensional keystroke datasets. Using machine learning classifiers, we identify the best-performing model for authenticating the students. The results indicate that the highest accuracy (83%) is achieved by the Isolation Forest classifier. Furthermore, to validate the results, the approach is applied to Carnegie Mellon University (CMU) benchmark dataset, thereby achieving an improved accuracy of 94%. Though we also used mouse dynamics for authentication, but its subpar performance leads us to not consider it for our approach.
DOCUMENT
Background: Shared decision-making is one key element of interprofessional collaboration. Communication is often considered to be the main reason for inefficient or ineffective collaboration. Little is known about group dynamics in the process of shared decision-making in a team with professionals, including the patient or their parent. This study aimed to evaluate just that. Methods: Simulation-based training was provided for groups of medical and allied health profession students from universities across the globe. In an overt ethnographic research design, passive observations were made to ensure careful observations and accurate reporting. The training offered the context to directly experience the behaviors and interactions of a group of people. Results: Overall, 39 different goals were defined in different orders of prioritizing and with different time frames or intervention ideas. Shared decision-making was lacking, and groups chose to convince the parents when a conflict arose. Group dynamics made parents verbally agree with professionals, although their non-verbal communication was not in congruence with that. Conclusions: The outcome and goalsetting of an interprofessional meeting are highly influenced by group dynamics. The vision, structure, process, and results of the meeting are affected by multiple inter- or intrapersonal factors.
DOCUMENT
An important performance determinant in wheelchair sports is the power exchanged between the athletewheelchair combination and the environment, in short, mechanical power. Inertial measurement units (IMUs) might be used to estimate the exchanged mechanical power during wheelchair sports practice. However, to validly apply IMUs for mechanical power assessment in wheelchair sports, a well-founded and unambiguous theoretical framework is required that follows the dynamics of manual wheelchair propulsion. Therefore, this research has two goals. First, to present a theoretical framework that supports the use of IMUs to estimate power output via power balance equations. Second, to demonstrate the use of the IMU-based power estimates during wheelchair propulsion based on experimental data. Mechanical power during straight-line wheelchair propulsion on a treadmill was estimated using a wheel mounted IMU and was subsequently compared to optical motion capture data serving as a reference. IMU-based power was calculated from rolling resistance (estimated from drag tests) and change in kinetic energy (estimated using wheelchair velocity and wheelchair acceleration). The results reveal no significant difference between reference power values and the proposed IMU-based power (1.8% mean difference, N.S.). As the estimated rolling resistance shows a 0.9–1.7% underestimation, over time, IMU-based power will be slightly underestimated as well. To conclude, the theoretical framework and the resulting IMU model seems to provide acceptable estimates of mechanical power during straight-line wheelchair propulsion in wheelchair (sports) practice, and it is an important first step towards feasible power estimations in all wheelchair sports situations.
DOCUMENT
Public transgressions by group members threaten the public image of a group when outside observers perceive them as representative of the group in general. In three studies, we tested the effectiveness of rejection of a deviant group member who made a racist comment in public, and compared this to several other strategies the group could employ to protect their image. In Study 1 (N¼75) and Study 2 (N¼51), the group was judged less racist after rejecting the deviant than after claiming a non-racist position or not responding to the transgression. Perceived typicality of the deviant partially mediated this effect in Study 2. In Study 3 (N¼81), the group was judged least racist after forcing the deviant to apologize and as most racist after denying the severity of the transgression. Results also showed a negative side-effect of rejection. Perceived exclusion of the deviant contributed to a perception of the group as disloyal to its members, which resulted in a less favorable overall group evaluation. Potential benefits and risks of rejection, denial, and apologies are further discussed in the General Discussion.
DOCUMENT
Blog post where the author speaks about his recently published article "Adherence to an injury prevention program in male amateur football players is affected by players’ age, experience and perceptions"
LINK
On 13 June 2018, Susana Menéndez said farewell as member of the Executive Board of The Hague University of Applied Sciences. To mark that occasion, a symposium was held on leadership in the internationalization of higher education, of which Susana has been a champion over the past ten years.
DOCUMENT
Despite the notable strides that have been made in terms of participation in sport, women continue to be underrepresented in sport leadership roles such as coaching and officiating. The 2014 United Nations (UN) International Working Group on Women’s Sport (IWG) noted that: ‘Women are significantly under-represented in management, administration, coaching and officiating, particularly at the higher levels’ (IWG, 2014 p. 6). This statement, part of the Helsinki Declaration, was made in the context of how sport can support the UN Millennium Development Goals. Across today’s sporting landscape, women’s sport experiences typically occur in male-dominated contexts, which favour men and masculinity (Norman, 2016). Recent data indicates the men to women ratio in high-performance coaching over the last four consecutive Olympic cycles has been approximately 10:1. Among US high school sporting officials, only 11% are women, and even a greater disparity exists with officiating sports traditionally played by men (Nordstrom, Warner, & Barnes, 2016). This data highlights a systemic absence of women in coaching and officiating leadership roles across sport. In this chapter we will discuss the impact this has on developing sport for women and girls. Specifically, this chapter aims to: - Provide an understanding of the roles and responsibilities of coaches and officials in women and girls sport delivery. - Explore career development pathways for improving opportunities for women in coaching and officiating. - Present a critical reflection of the differences and similarities between athlete development and coach/official development (systems and structures) for women and girls. We begin by discussing the gendered nature of coaching before turning our attention to women’s experiences in sport officiating. We draw on relevant literature throughout the chapter and identify issues and opportunities for further research. We conclude by providing practical actions and recommendations to help facilitate coaching and officiating development for women and girls LinkedIn: https://www.linkedin.com/in/donna-de-haan/
MULTIFILE
Online support communities are gaining attention among child-attracted persons (CAPs). Though research has largely focused on the negative consequences these environments create for potential offending, they may also provide a beneficial alternative to more formal treatment settings. To assess the utility for clinical and therapeutic purposes, this analysis focused on subcultural dynamics to examine self-reported wellbeing outcomes of participation in a Dutch forum for CAPs. A total of 15 semi-structured interviews were conducted with moderators, members and mental health professionals involved in the community. Thematic analyses demonstrated that by means of informal social control, bonds of trust and social relational education, the network aims to regulate the behavior and enhance the wellbeing of its marginalized participants. Key outcomes include a decreased sense of loneliness and better coping with stigma, to the point that participants experience less suicidal thoughts. Association with prosocial peers also helps to set moral boundaries regarding behavior towards children, although we cannot fully rule out potential adverse influences. Online support networks offer a stepping stone to professional care that fits individual needs of CAPs, while also providing an informal environment that overcomes limitations of physical therapy and that extents principles of existing prevention and desistance approaches. Gepubliceerd door uitgever Sage: Bekkers, L. M. J., Leukfeldt, E. R., & Holt, T. J. (2024). Online Communities for Child-Attracted Persons as Informal Mental Health Care: Exploring Self-Reported Wellbeing Outcomes. Sexual Abuse, 36(2), 158-184. https://doi.org/10.1177/10790632231154882
DOCUMENT
Sports are activities enjoyed by many across the globe, regardless of age. The existence and promotion of youth sports has often been based on various assumptions about its value and role in society. Sports participation is assumed to be fun and good and is assumed to contribute to the development of young people. As a result, sports are often seen as an essential part of life for youth. Participation in sports and physical activity is assumed to help young people to develop in a context in which they are able to learn important positive societal values (Fraser-Thomas et al., 2005; Holt, 2008). Although there is a widespread belief in the positive dimensions of sports participation for young people, there is a need for research and theory that identifies and critically looks at the processes through which sports participation by youth is experienced and shapes their lives (Coakley, 2011). I return to this critical perspective after I elaborate on the ways sports are viewed as important effective activities for positive youth development.
DOCUMENT
