The Effects of Explicit Listening Strategy Instruction on the Listening Comprehension of English as Second Language (ESL) Community College Students

This mixed methods study explored the effects of explicit listening strategy instruction on the beginning-level ESL learner\u27s listening comprehension at a community college in Northern California. Most previous studies measured the effectiveness of listening strategy instruction by comparing students\u27 test scores, but little research explored the students\u27 listening strategy development and their perceptions of the strategy instruction. Furthermore, no prior research exists on the effects of listening strategy instruction among community college students. The researcher employed the concurrent triangulation approach, collecting and analyzing both quantitative and qualitative data simultaneously. Data sources included interviews, a listening test, background surveys, and classroom observations. A total of 52 students participated in the research, including 30 in the treatment group and 22 in the control group. Based on the initial findings, the researcher provided explicit instruction of listening strategies to the treatment group. The qualitative findings of the present study showed positive changes in students\u27 listening strategy use after the strategy instruction. In addition, the findings revealed that students noticed improvement in their listening abilities and other areas as a result of efficiently utilizing the listening strategies. The quantitative findings resulting from the independent sample t-test revealed a statistically significant difference in gain score means between the control and treatment groups. Thus, the qualitative and quantitative findings converged and suggested that the explicit teaching of listening strategies did have positive effects on community college ESL students\u27 listening comprehension. This study has implications for the fields of research methods, language teaching pedagogy, listening strategies, strategy instruction, and strategy assessment among ESL and EFL learners. More research on explicit listening strategy instruction in adult education would further expand the current understanding of the effects of strategy instruction and to identify curricular implications

Towards the Implementation and Evaluation of Semi-Partitioned Multi-Core Scheduling

Recent theoretical studies have shown that partitioning-based scheduling has better real-time performance than other scheduling paradigms like global scheduling on multi-cores. Especially, a class of partitioning-based scheduling algorithms (called semi-partitioned scheduling), which allow to split a small number of tasks among different cores, offer very high resource utilization, and appear to be a promising solution for scheduling real-time systems on multi-cores. The major concern about the semi-partitioned scheduling is that due to the task splitting, some tasks will migrate from one core to another at run time, and might incur higher context switch overhead than partitioned scheduling. So one would suspect whether the extra overhead caused by task splitting would counteract the theoretical performance gain of semi-partitioned scheduling. In this work, we implement a semi-partitioned scheduler in the Linux operating system, and run experiments on a Intel Core-i7 4-cores machine to measure the real overhead in both partitioned scheduling and semi-partitioned scheduling. Then we integrate the obtained overhead into the state-of-the-art partitioned scheduling and semi-partitioned scheduling algorithms, and conduct empirical comparison of their real-time performance. Our results show that the extra overhead caused by task splitting in semi-partitioned scheduling is very low, and its effect on the system schedulability is very small. Semi-partitioned scheduling indeed outperforms partitioned scheduling in realistic systems