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探討身體素養在COVID後疫情時代老年人參與體育運動中的角色
No full textThe outbreak of COVID-19 has had a significant impact on various aspects of daily life, including physical activities (PAs) and health, leading to the introduction of online teaching and learning at all levels and fields, including sport and physical education (PE). Therefore, this research identified the pathways between the physical literacy (PL), self-efficacy (SE), intrinsic motivation (IM), and course satisfaction (SAT) of older adults in online sports course learning contexts. This research utilized convenience sampling methods to collect data from 60 surveys distributed to older adults participating in senior online sports courses at a university in Taiwan in 2021. Descriptive statistics, Pearson's correlation test, and hierarchical regression were used to analyze the data. The results indicated that PL is positively associated with IM, SE, and SAT. Furthermore, IM in sporting contexts is a potential mediator between PL and SAT. However, SE is not have significantly associated with the mediation between PL and IM. The findings of this research suggested that PL is directly related to SE and IM, and it's also associated with higher SAT through the state of IM in older adults. Therefore, it is essential to strengthen the PL of older adults and promote their continuous participation in PA behaviors actively, as this is an important indicator of healthy aging.補正完畢TW
Forced waves of a delayed diffusive endemic model with shifting transmission rates
No full textIn this paper, we investigate the forced waves of a delayed diffusive endemic model with a shifting transmission rate. Here a forced wave is a traveling wave with wave speed the same as the environmental shifting speed. By constructing a new pair of upper-lower solutions, we prove the existence of forced waves for any negative shifting speed which corresponds the deceased of the disease, regardless of the magnitude of the delay. Moreover, we also derive the existence of forced waves with small shifting speeds without delay which signify the disease spread. A non-existence of forced wave when the limiting reproduction number is less than one is also proven.補正完畢NL
Empirical analysis of jump dynamics, heavy-tails and skewness on value-at-risk estimation
No full textThis study provides a comprehensive analysis of the possible influences of jump dynamics, heavy-tails, and skewness with regard to VaR estimates through the assessment of both accuracy and efficiency. To this end, the ARJI model, and its degenerative GARCH model with normal, GED, and skewed normal (SN) distributions were adopted to capture the properties of time-varying volatility, time-varying jump intensity, heavy-tails and skewness, for a range of stock indices across international stock markets during the period of the U.S. subprime mortgage crisis. Empirical results show that, with regard to the evaluation of accuracy, the role of jump dynamics is more substantial than heavy-tails or skewness as it pertains to VaR accuracy at the 90% and 95% levels, while heavy-tails become more important at the 99% level for a long position. However, the influence of the abovementioned properties on VaR estimation does not appear substantial for a short position. In addition, the properties of jump dynamics and skewness appear to be beneficial for the improvement of efficiency.補正完畢US
Jump risk of Presidential election: evidence from Taiwan stock and foreign exchange markets
No full textThis article employs jump-diffusion models, including the ARJI model and the GARCH-jump model, to examine jump intensity and volatility of Taiwan stock and foreign exchange markets during a Presidential election period. The empirical results indicate that, firstly, the ARJI model fits data better than the GARCH-jump model. Secondly, the Presidential election events enhance the jump intensity of both markets and the jump-induced variance is higher than diffusion-induced variance. It reveals the importance of the discrete jump process during a Presidential election period, and might provide some implications for option pricing or hedging strategy. Due to the intervention of the Central Bank in the foreign exchange market during a Presidential election period, the results indicate that jump intensity and volatility of jump size are more moderate.補正完畢US
Do price jumps matter in volatility forecasts of US treasury futures?
No full textThis study investigates volatility forecasts in the US Treasury futures market and emphasizes the importance of price jumps across various maturities under moderate and sharp interest rate rising scenarios. We assess out-of-sample forecasting performance not only with statistical method but economic method based on a volatility timing strategy. Our findings indicate that models including price jumps specifications exhibit substantial enhancements in both evaluation methods over the entire out-of-sample period, particular for the period of sharp interest rate rising. Our results are robust to nonparametric jump tests used in this study, transaction costs, and portfolio rebalancing method.補正完畢US
Energy-Balanced Optimization on Flying Ferry Placement for Data Gathering in Wireless Sensor Networks
No full textDeploying flying ferries in large-scaled wireless sensor networks can prevent data gathering and distribution from physical communication restrictions on the ground. Ferry-assisted data distribution is straightfoward and manageable, as compared with traditional ad hoc routing over weak and multi-hop wireless networks. Our study exploits the notion of a ferry fleet that conducts teamwork for data gathering in such environments. To maximize the lifetime of a ferry fleet, we propose a fair and energy-balanced ferry fleet placement scheme, named as FEB for brevity, as jointly considering the efficiency, balance, and fairness of energy consumption. This scheme operates two mutual phases. The first phase demarcates service regions in a network using the powered-Voronoi diagram. The second phase decides a shortest-path itinerary across sensors in every service region using a genetic-based alternative of the traveling salesman problem (TSP) algorithm. Thus, this scheme is able to ensure fair task assignment, balance energy consumption, and prolong the lifetime among multiple ferries in teamwork. Performance results show that the proposed scheme outperforms several typical schemes, including Native, K-Means and Spiral, in terms of cumulative energy computation, residual energy distribution, Jain's fairness index on energy utilization, the number of alive ferries, and the total of task execution times during ferry teamwork.補正完畢TW
From the Perspective of "Hedging" to "Soft Balance": The Remaking of EU-China Policy
No full text本文主要探討2013至2023年這十年間歐中關係的轉變：2013年雙方建立「全面夥伴關係」十週年，也是中國推動「帶路倡議」發展的年代。歐盟對中政策採用避險的兩手策略，一方面與之交往，一方面防範，期望透過密切的經貿聯繫帶動中國政治的改革；2019年之後歐盟將中國視為合作「夥伴」、經濟「競爭者」與體制「對手」。歐盟開始正視中國經濟擴張背後政治的企圖心。此時歐盟對中政策逐漸走向柔性平衡。雙邊關係呈現出一種排除軍事硬性抗衡，選擇在柔性議題合作或對抗的策略，建構起本文柔性平衡的基本概念。補正完畢TW
