No amount of crystal ball gazing may help us fathom the full impact of the Covid-19 (C-19) crisis on business organizations in a distinct manner. Given the lack of precedence, any such analyses seem to demand routine revisions as we progress further up the “number of infected” curve. Most countries of the world have imposed restrictions on social congregations or even people working in close proximity to each other. Industries that produce and deliver information products and services therefore, have continued to function while those that manufacture physical products especially labor-intensive firms were forced to minimize operations or temporarily shut down. However, in most countries, physical products which were essential in nature were reluctantly permitted to be manufactured given the need for them in people’s everyday life. In this viewpoint, I draw upon three dimensions – information intensity of product/service, information intensity of process/value chain; along with a third dimension – essential nature of the product/service to help understand the immediate implications of C-19. I also present some anecdotal evidences of attempts to alter business models in these circumstances in order to address the challenges that certain product characteristics impose but at the same capitalize on the business opportunities presented by the essentiality of the products. 相似文献
In longitudinal design, investigating interindividual differences of intraindividual changes enables researchers to better understand the potential variety of development and growth. Although latent growth curve mixture models have been widely used, unstructured finite mixture models (uFMMs) are also useful as a preliminary tool and are expected to be more robust in identifying classes under the influence of possible model misspecifications, which are very common in actual practice. In this study, large-scale simulations were performed in which various normal uFMMs and nonnormal uFMMs were fit to evaluate their utility and the performance of each model selection procedure for estimating the number of classes in longitudinal designs. Results show that normal uFMMs assuming invariance of variance–covariance structures among classes perform better on average. Among model selection procedures, the Calinski–Harabasz statistic, which has a nonparametric nature, performed better on average than information criteria, including the Bayesian information criterion. 相似文献
The purpose of this study was to estimate the optimal body size, limb-segment length, girth or breadth ratios for 100-m backstroke mean speed performance in young swimmers. Sixty-three young swimmers (boys [n = 30; age: 13.98 ± 0.58 years]; girls [n = 33; age: 13.02 ± 1.20 years]) participated in this study. To identify the optimal body size and body composition components associated with 100-m backstroke speed performance, we adopted a multiplicative allometric log-linear regression model, which was refined using backward elimination. The multiplicative allometric model exploring the association between 100-m backstroke mean speed performance and the different somatic measurements estimated that biological age, sitting height, leg length for the lower-limbs, and two girths (forearm and arm relaxed girth) are the key predictors. Stature and body mass did not contribute to the model, suggesting that the advantage of longer levers was limb-specific rather than a general whole-body advantage. In fact, it is only by adopting multiplicative allometric models that the abovementioned ratios could have been derived. These findings highlighted the importance of considering somatic characteristics of young backstroke swimmers and can help swimming coaches to classify their swimmers and enable them to suggest what might be the swimmers’ most appropriate stroke (talent identification). 相似文献
Purpose: This study discusses the process of co-constructing a prototype pedagogical model for working with youth from socially vulnerable backgrounds.
Participants and settings: This six-month activist research project was conducted in a soccer program in a socially vulnerable area of Brazil in 2013. The study included 17 youths, 4 coaches, a pedagogic coordinator and a social worker. An expert in student-centered pedagogy and inquiry-based activism assisted as a debriefer helping in the progressive data analysis and the planning of the work sessions.
Data collection/analysis: Multiple sources of data were collected, including 38 field journal/observation and audio records of: 18 youth work sessions, 16 coaches’ work sessions, 3 combined coaches and youth work sessions, and 37 meetings between the researcher and the expert.
Findings: The process of co-construction of this prototype pedagogical model was divided into three phases. The first phase involved the youth and coaches identifying barriers to sport opportunities in their community. In the second phase, the youth, coaches and researchers imagined alternative possibilities to the barriers identified. In the final phase, we worked collaboratively to create realistic opportunities for the youth to begin to negotiate some of the barriers they identified. In this phase, the coaches and youth designed an action plan to implement (involving a Leadership Program) aimed at addressing the youths’ needs in the sport program. Five critical elements of a prototype pedagogical model were co-created through the first two processes and four learning aspirations emerged in the last phase of the project.
Implications: We suggest an activist approach of co-creating a pedagogical model of sport for working with youth from socially vulnerable backgrounds is beneficial. That is, creating opportunities for youth to learn to name, critique and negotiate barriers to their engagement in sport in order to create empowering possibilities. 相似文献
On a kayak ergometer, an accurate simulation of the athlete-paddle-kayak system kinematics is essential for analysing the relationship between technique and performance. The purpose of this study
was to establish a strong relationship between performances on flatwater and performances on an ergometer by means of propulsive
force measurement and drag models. Two trials were performed by 12 kayakers in which they were first timed over 250 m of flatwater
kayaking (the reference test) and were then asked to perform a trial of the same duration on the ergometer with the same perceived
physical exertion. Three techniques for measuring propulsive force and three drag models generated nine combinations, which
were all evaluated for their ability to estimate kayak velocity. For each combination, the distance covered by the athlete
on the ergometer was simulated. A kayakers’ ergometer ranking was based on the average velocity in the ergometer trial. Both
distance and ranking were compared to the on-water results. The simulation with the best combination of force measurement
and drag model gave an accurate estimate of distance (253 ± 10.5 vs. 250 m) and ranking compared to the reference test. 相似文献