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Live video streaming has become one of the key applications in mobile wireless networks. To offload the bandwidth requirement in both backhaul and radio access networks, the integration of Mobile Edge Computing (MEC) and multicasting have become a natural candidate. However, less attention has been paid to the user Quality of Experience-driven (QoE-driven) approach to optimize the radio resource management of multicasting in mobile wireless networks. In this work, we study the optimal radio resource management, including modulation and coding scheme (MCS) selection, radio resource blocks allocation, and Forward Error Correction (FEC), for multicasting in LTE networks with the assistance of MEC. We formulate it as a convex optimization problem and propose a weighted sub-gradient (WSG) method to find the near-optimal solution. In addition, we also propose a heuristic algorithm based on the concept of Maximizing marginal Gain and Minimizing marginal Loss (MGML). Our simulation results show that both approaches are able to achieve near-optimal solutions and outperform previous work, including MSML [11] and OLM [14] . Our simulation results also show that WSG yields the best QoE fairness index while MGML yields the best system utility in most scenarios.

The present study defined four types of stances/positions in students' argumentation regarding socio-scientific issues (SSIs): affirmative (A), oppositional (O), multiple (M), and non-committal (N) positions. The central goal of this study was to examine the effect of students' positions toward an issue on the science conceptual understanding and quality of their arguments. Three types of debates were concerned due to their abundant production of arguments: the debates between the (1) O vs. A, (2) O vs. M, and (3) O vs. N position students. The quasi-experimental design was adopted in which three 11th grade classes totaling 108 students were invited. They were assigned to the three required types of debate according to their positions regarding two given SSIs. The results showed that there were significant differences among the three debates on both the conceptual understanding and arguments produced by the students. The OA debate exhibited the best performance no matter in the conceptual understanding and the use of claims, warrants, and rebuttals. Moreover, the OM debate exhibited the best performance in terms of the use of qualifiers, whereas the ON debate students exhibited the lowest abilities and improvements.

Background: Healthcare-associated infections (HAIs) cause increases in length of stay, mortality, and healthcare costs. A previous study conducted in Taiwan obtained similar results to those reported in Korea and Japan in 2015. Changes in microorganisms have been noted in recent years. Understanding the recent condition of HAIs in intensive care units (ICUs) can enable healthcare providers to develop effective infection control protocols to reduce HAIs. Methods: We used the Taiwan Nosocomial Infection Surveillance System to evaluate the incidence densities of HAIs, the proportions of causative pathogens, and the proportions of antimicrobial resistance (AMR). The Poisson regression model was constructed to incidence density, and the chi-square test was used to assess proportion. Results: The incidence density of HAIs decreased 5.7 to 5.4 per 1000 person-days. However, the proportions of Klebsiella pneumoniae and Enterococcus faecium significantly increased. In addition, the proportions of carbapenem-resistant K. pneumoniae and vancomycin-resistant Enterococcus faecium significantly increased over time. Conclusion: Analysis of the microorganisms involved in HAIs in ICUs showed elevated proportions of K. pneumoniae and E. faecium with AMR. Infection control protocols have been implemented for several years and require improvements regarding environmental cleanliness and medical staff prevention.

The purpose of this study was to compare the influence of a single-player game with that of a collaborative game on students' motivation, attention levels, and relaxation levels in a motion-sensing learning environment. Participants were 20 college students in a higher education institution in southern Taiwan. A Kinect-based game with motion-sensing technology was incorporated to help the students enhance their attention levels and reduce their anxiety. Results showed that when the students worked collaboratively, they achieved higher learning motivation. In addition, brainwave data revealed that during the gaming activities, the students' attention levels in both conditions increased. It is suggested that instructors can incorporate collaborative learning environments with a Kinect motion-sensing platform to enhance students' learning motivation.

Argumentation is an important aspect of the scientific education. The purpose of the present studies was to explore the influences of two variables termed "the argumentation strategy" and "the kind of science concept" on student's argumentation in the web-based learning environment. There were two types of argumentation strategies (individual or collaborative) and two kinds of science concepts (descriptive or theoretical) identified for our experimental investigations. The quasi-experimental method was applied in which 138 7th grade students were invited and then assigned into either individual group (N=68) or collaborative group (N=70) randomly. They then participated into a web-based learning pro-gram we developed for six science topics, including three descriptive and three theoretical topics. Several scaffoldings were embedded into the program explicitly and systematically, such as multi-media, a discussion block, and scripts in order to promote students' learning engagement. The students' arguments pro-posed during the web-based learning, including claims, warrants, backings and rebuttals were clarified, coded, and then analyzed. The results showed the argumentation strategy has a significant effect on students' argumentation only in the theoretical topics. The post-hoc analysis showed the students in the collaborative group outperformed their peers significantly in the individual group. In theoretical science topic, the students needed more scaffoldings to acquire an in-depth understanding which supports them to construct multiple types of arguments. Moreover, the students in both groups made significant improvements no matter for the descriptive or the theoretical topics, implying the web-based learning pro-gram was effective for argumentation learning.

The present study investigated the effects of online argumentation scaffolding on students’ argumentation involving hypothetical and theoretical biological concepts. Two types of scaffolding were developed in order to improve student argumentation: continuous scaffolding and withdraw scaffolding. A quasi-experimental design was used with four 8th-grade classes comprising a total of 124 students. Two classes (63 students) were assigned into the continuous scaffolding group, while the other two (61 students) were assigned into the withdraw scaffolding group. All the students participated in online argumentation regarding four units, including two hypothetical concepts and two theoretical concepts. Both online learning process and scientific argumentation assessment results indicated that the continuous scaffolding group performed significantly better in terms of the quality and quantity of argumentation than the withdraw scaffolding group with regard to the hypothetical biology concepts, particularly in generating rebuttal arguments. In addition, the results also showed that both the continuous group and withdraw group students had better argumentation performance with regard to the hypothetical biology concepts than the theoretical biology concepts. Taken together, the study results suggest that learning argumentation through theoretical biology concepts is more difficult than doing so through hypothetical biology concepts.

This paper presents a converter design for fuel cell operations enhanced with a cooperation of supercapacitors and lithium batteries. The study is motivated because the properties of connected sources of fuel cell, lithium battery and super-capacitor are mutually different. An integrated converter with the energy control to regulate the power flow hence becomes crucially important. In the study, through the utilization of an improved step-down circuit along with the isolated circuit design, the completed converter is proved effective to supply power from fuel cells along with a backup support of supercapacitors and lithium batteries. By validating this proposed circuit under different load scenarios, test results help confirm the practical values of this design for green energy applications.

In recent years, web development is the most important application in internet. Caching related technique improves the web server performance significantly. However, existing caching schemes cannot deal with the dynamic web pages efficiently. Thus, in this paper, we propose a caching scheme and then use web session objects and database-related dynamic web cache to implement the dynamic web cache system in Tomcat web server. We show how to build the dependency between dynamic web pages and the underlying database fields and session objects. Our experimental results show that Tomcat with proposed dynamic web cache can increase the stability of web server and improve web server throughput by up to 290%.