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1.
高危险性体育项目相对一般体育项目而言,是具有危险性大、专业技术性强、安全保障要求高等特点的体育活动。我国对高危险性体育项目有一定的法律规制,但存在顶层设计缺失、法律制度之间的冲突与不一致、可操作性不足等问题。这些制度缺陷产生的根源在于对立法必要性的认识不足、立法不作为,缺乏有效的立法监督机制等,现有制度的缺陷与不足会影响我国高危险性体育项目的发展,难以满足人们体育文化活动的需要。鉴于此,我国应逐步完善高危险性体育项目的法律规制,包括完善高危险性体育项目的审定主体,明确经营高危险性体育项目的主体范围、完善高危险性体育项目的行政许可条件、强化高危险体育项目行政监管以及风险防范等。  相似文献   
2.
本文通过对S大学的研究,探讨高校第二课堂运行的有效性,并指出目前存在的问题,提供相应的解决办法。  相似文献   
3.
This review presents a conceptual framework and supporting evidence that links impaired motor control after sport-related concussion (SRC) to increased risk for musculoskeletal injury. Multiple studies have found that athletes who are post-SRC have higher risk for musculoskeletal injury compared to their counterparts. A small body of research suggests that impairments in motor control are associated with musculoskeletal injury risk. Motor control involves the perception and processing of sensory information and subsequent coordination of motor output within the central nervous system to perform a motor task. Motor control is inclusive of motor planning and motor learning. If sensory information is not accurately perceived or there is interference with sensory information processing and cognition, motor function will be altered, and an athlete may become vulnerable to injury during sport participation. Athletes with SRC show neuroanatomic and neurophysiological changes relevant to motor control even after meeting return to sport criteria, including a normal neurological examination, resolution of symptoms, and return to baseline function on traditional concussion testing. In conjunction, altered motor function is demonstrated after SRC in muscle activation and force production, movement patterns, balance/postural stability, and motor task performance, especially performance of a motor task paired with a cognitive task (i.e., dual-task condition). The clinical implications of this conceptual framework include a need to intentionally address motor control impairments after SRC to mitigate musculoskeletal injury risk and to monitor motor control as the athlete progresses through the return to sport continuum.  相似文献   
4.
ABSTRACT

Interval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI ?32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI ?2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10–15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations.  相似文献   
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6.
《Sport Management Review》2020,23(2):315-329
In many countries, voluntary sports clubs are the main recipients of public subsidies regarding the provision of recreational sport, and the economically most important level of government is usually the local government (i.e. the municipalities). The purpose of this article is to examine whether and how municipal framework conditions matter for sports clubs. Inspired by previous studies, we examine the role of direct and indirect public subsidies as well as facility coverage. The authors conduct analyses on a general level (for all sports) and specifically for five sports (badminton, football, gymnastics, handball and swimming). The differentiation between sports allows us to examine how municipal framework conditions might be associated differently with density and participation across sports. In the statistical analyses, the authors apply data collected among all 98 Danish municipalities. The results show that the municipal levels of direct and indirect subsidies are weakly correlated with both the density of and participation in sports clubs, while stronger correlations can be identified with regard to facility coverage. The analyses for the five sports reveal that the supply of relevant facility types is – with few exceptions – positively correlated with sports club density and participation levels within each sport. Thus, facility coverage seems to play a more important role for sports clubs than the levels of indirect and particularly direct subsidies.  相似文献   
7.
Recently, models that based on Transformer (Vaswani et al., 2017) have yielded superior results in many sequence modeling tasks. The ability of Transformer to capture long-range dependencies and interactions makes it possible to apply it in the field of portfolio management (PM). However, the built-in quadratic complexity of the Transformer prevents its direct application to the PM task. To solve this problem, in this paper, we propose a deep reinforcement learning-based PM framework called LSRE-CAAN, with two important components: a long sequence representations extractor and a cross-asset attention network. Direct Policy Gradient is used to solve the sequential decision problem in the PM process. We conduct numerical experiments in three aspects using four different cryptocurrency datasets, and the empirical results show that our framework is more effective than both traditional and state-of-the-art (SOTA) online portfolio strategies, achieving a 6x return on the best dataset. In terms of risk metrics, our framework has an average volatility risk of 0.46 and an average maximum drawdown risk of 0.27 across the four datasets, both of which are lower than the vast majority of SOTA strategies. In addition, while the vast majority of SOTA strategies maintain a poor turnover rate of approximately greater than 50% on average, our framework enjoys a relatively low turnover rate on all datasets, efficiency analysis illustrates that our framework no longer has the quadratic dependency limitation.  相似文献   
8.
以一个销售商驱动的低碳再制造闭环供应链为研究对象,用均值-方差刻画风险特性,分析研究低碳产品市场和废旧低碳产品市场均为随机市场需求情境下、零和博弈和集中决策下闭环供应链中,低碳产品销售价、交易价格、低碳废旧产品回收价格等变量和节点企业期望效用及整个链条期望效用的变化规律。研究表明:零和博弈下低碳闭环供应链未能实现优化和协调。最后,设计正向渠道收益共享、逆向渠道风险共担契约,实现低碳再制造闭环供应链的协调,并通过数值仿真和灵敏度分析验证该模型的有效性及实用性。  相似文献   
9.
The rapid development of e-commerce is driving many traditional manufacturing enterprises to establish online channels. This typically leads to online and offline channel conflicts for these enterprises. Existing studies on channel conflict management primarily focus on describing the conflicts and discussing the types of strategies. Utilizing the case study method and taking the resource orchestration perspective as the theoretical lens, this study examines the implementation processes of online and offline channel integration and segmentation strategies in two Chinese manufacturing enterprises. The findings reveal the prerequisite to select online and offline integration and segmentation strategies, and specific resource orchestration actions and capabilities generated under the guidance of the integration and segmentation strategies. This study has theoretical implications to the online and offline channel conflict management strategies by extending the “what” question to the “how” question. In addition, this study also provides references to practitioners for selecting and implementing appropriate online and offline channel conflict management strategies.  相似文献   
10.
Cloud computing is a popular outsourcing solution for organizations to support the information management during the life cycle of digital information goods. However, outsourcing management with a public provider results in a lack of control over digital products, which could produce incidents such as data unavailability during service outages, violations of confidentiality and/or legal issues. This paper presents a novel distribution model of digital products inspired by lean supply chain principles called CloudChain, which has been designed to support the information management during digital product lifecycle. This model enables connected networks of customers, partners and organizations to conduct the stages of digital product lifecycle as value chains. Virtual distribution channels are created over cloud resources for applications of organizations to deliver digital products to applications of partners through a seamless information flow. A configurable packing and logistic service was developed to ensure confidentiality and privacy in the product delivery by using encrypted packs. A chain management architecture enables organizations to keep tighter control over their value chains, distribution channels and digital products. CloudChain software instances were integrated to an information management system of a space agency. In an experimental evaluation CloudChain prototype was evaluated in a private cloud where the feasibility of applying supply chain principles to the delivery of digital products in terms of efficiency, flexibility and security was revealed.  相似文献   
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