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1.
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   
2.
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   
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《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   
5.
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   
6.
Imbalanced sample distribution is usually the main reason for the performance degradation of machine learning algorithms. Based on this, this study proposes a hybrid framework (RGAN-EL) combining generative adversarial networks and ensemble learning method to improve the classification performance of imbalanced data. Firstly, we propose a training sample selection strategy based on roulette wheel selection method to make GAN pay more attention to the class overlapping area when fitting the sample distribution. Secondly, we design two kinds of generator training loss, and propose a noise sample filtering method to improve the quality of generated samples. Then, minority class samples are oversampled using the improved RGAN to obtain a balanced training sample set. Finally, combined with the ensemble learning strategy, the final training and prediction are carried out. We conducted experiments on 41 real imbalanced data sets using two evaluation indexes: F1-score and AUC. Specifically, we compare RGAN-EL with six typical ensemble learning; RGAN is compared with three typical GAN models. The experimental results show that RGAN-EL is significantly better than the other six ensemble learning methods, and RGAN is greatly improved compared with three classical GAN models.  相似文献   
7.
京津冀高技术产业技术供需协同研究   总被引:1,自引:1,他引:0  
构建高技术产业技术供需复合系统序参量指标体系,运用距离协同模型并融合熵理论对京津冀技术供需系统2005—2015年的协同水平进行研究发现:京津冀高技术产业技术供需协同水平呈波动上升趋势,并实现从弱协同到基本协同阶段的过渡;京津冀区域协同发展对技术供需水平的提高起重要推动作用;各地技术资源禀赋异质导致高技术产业技术供给要素与需求的协同水平及需求要素与供给的协同水平呈差异性,且专利技术供需协同面临较大挑战。基于此,在推动技术需求驱动的技术交易市场体系建立,提高有效技术评估、筛选与供给,完善区域技术供需对接机制,推进技术中介服务体系建设等方面提出促进区域高技术产业技术供需协同发展的对策建议。  相似文献   
8.
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   
9.
This paper aims to demonstrate how the huge amount of Social Big Data available from tourists can nurture the value creation process for a Smart Tourism Destination. Applying a multiple-case study analysis, the paper explores a set of regional tourist experiences related to a Southern European region and destination, to derive patterns and opportunities of value creation generated by Big Data in tourism. Findings present and discuss evidence in terms of improving decision-making, creating marketing strategies with more personalized offerings, transparency and trust in dialogue with customers and stakeholders, and emergence of new business models. Finally, implications are presented for researchers and practitioners interested in the managerial exploitation of Big Data in the context of information-intensive industries and mainly in Tourism.  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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