A method of providing accurate velocity feedback of performance on an instrumented kayak ergometer

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.     

‘The life of crime does not pay; stop and think!’: the process of co-constructing a prototype pedagogical model of sport for working with youth from socially vulnerable backgrounds

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.     

共轨式喷油系统数学模型

针对高压共轨喷油系统所特有的工作过程和部件结构 ,建立了系统各部件综合的数学模型 ,并采用有限容积法对方程进行了离散 ,对系统的压力特性、电磁特性和控制参数等进行了仿真 ,为系统的参数设计、标定提供了依据。     

试析美国研究型大学基层学术组织模式

美国研究型大学基层学术组织是以学科为基础的独立的、自主的学术组织。其组织规模主要根据教学科研任务的需要来决定。其内部管理以教授统治为主,采取的是少数服从多数的决策机制。总结和归纳美国研究型大学基层学术组织的现状与改革动向,对于探讨我国研究型大学未来的改革重点与方向具有重要的借鉴意义。     

对我国中小学体育教学模式的理论思考

着重对我国中小学体育教学模式进行理论探讨。提出了多视角、多样化、全方位的体育教学模式新格局,认为提高我国中小学体育教学整体水平的关键在于更新教育观念,建立一定的学说,确定“发展”的体育教学模式。     

From Retrieval Status Values to Probabilities of Relevance for Advanced IR Applications

Information Retrieval systems typically sort the result with respect to document retrieval status values (RSV). According to the Probability Ranking Principle, this ranking ensures optimum retrieval quality if the RSVs are monotonously increasing with the probabilities of relevance (as e.g. for probabilistic IR models). However, advanced applications like filtering or distributed retrieval require estimates of the actual probability of relevance. The relationship between the RSV of a document and its probability of relevance can be described by a normalisation function which maps the retrieval status value onto the probability of relevance (mapping functions). In this paper, we explore the use of linear and logistic mapping functions for different retrieval methods. In a series of upper-bound experiments, we compare the approximation quality of the different mapping functions. We also investigate the effect on the resulting retrieval quality in distributed retrieval (only merging, without resource selection). These experiments show that good estimates of the actual probability of relevance can be achieved, and that the logistic model outperforms the linear one. Retrieval quality for distributed retrieval is only slightly improved by using the logistic function.     

Examining the Causal Relationships Among Selected Antecedents of Responsible Environmental Behavior

Abstract

Attitude models have been widely applied to natural resource management to ensure responsible environmental behavior. For a variety of applications, the causality among selected antecedents, such as knowledge of environmental issues, locus of control, attitude, personal responsibility, and intention to act on responsible environmental behavior has not yet been tested empirically. A hypothesized causal model based on Hine's (1986) model on responsible environmental behavior was developed. The data from 523 visitors to the urban forest trail in the Kwang-Reung Arboretum, Korea, during September 1995 were used for testing the suggested causal model. Path analysis using the LISREL program tested the model fit and statistical effects of variables. In terms of the effects on intention to act, locus of control and attitude are more important than knowledge and personal responsibility. Our findings suggest that in order to enhance responsible environmental behavior, environmental education and interpretation systems need to focus on changing the internal locus of control. Several recommendations, limitations, and directions for future research are discussed.     

MRNS-9000型航海雷达模拟器船型编辑功能的开发

船舶操纵模拟器用于航道、港口开发已是当前先进而有效的手段。本文对“海河通航标准研究”课题在MRNS-9000型航海雷达模拟器上所进行的船型拟合工作作了概述,并提出了在航海雷达模拟器上拟合船舶数学模型时所采用的主要依据,即利用船舶操纵性标准、与在航船舶操纵行为密切相关的标准同船舶数学模型进行拟合。目前,此法已成功地用于“海河通航标准研究”这一课题中。同时,作者对船舶航行时受风力影响的问题也提出了看法。     

AI for Science：智能化科学设施变革基础研究

近年来，人工智能（AI）在前沿科技领域取得了诸如AlphaFold2、核聚变智能控制、新冠药物设计等诸多令人瞩目成果，表明AI for Science正在成为一种新的研究范式。实现智能时代的基础科学源头创新及其下游重大技术创新，需破解2个方面的核心问题：（1）如何利用新一代AI（特别是生成式AI及大模型）的通用性和创造性推动新范式的形成；（2）如何利用AI实现对传统科学设施的赋能与改造。文章提出一种智能化科学设施的建设构想，兼顾“高度智能化的科学新设施”和“AI赋能已有科学大设施”2个层面的需求，构筑AI for Science的科学设施体系，形成科学领域大模型、生成式模拟与反演、自主智能无人实验及大规模可信科研协作等创新功能，加速重大科学发现、变革性物质合成，以及重大工程技术应用。