• ETRI Journal
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• v.34 no.3
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• pp.330-340
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• 2012

In many applications of wireless sensor actor networks (WSANs) that often run in harsh environments, the reduction of completion times of tasks is highly desired. We present a new time-aware, energy-aware, and starvation-free algorithm called Scate for assigning tasks to actors while satisfying the scalability and distribution requirements of WSANs with semi-automated architecture. The proposed algorithm allows concurrent executions of any mix of small and large tasks and yet prevents probable starvation of tasks. To achieve this, it estimates the completion times of tasks on each available actor and then takes the remaining energies and the current workloads of these actors into account during task assignment to actors. The results of our experiments with a prototyped implementation of Scate show longer network lifetime, shorter makespan of resulting schedules, and more balanced loads on actors compared to when one of the three well-known task-scheduling algorithms, namely, the max-min, min-min, and opportunistic load balancing algorithms, is used.

• Human Ecology Research
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• v.59 no.4
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• pp.433-448
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• 2021

The purpose of this study was to analyze two subject competencies (practical problem-solving capability and independent life capability) reflected in the activity tasks included in the 'home life and safety' area of 12 middle school technology-home economics textbooks in accordance with the 2015 revised curriculum. The analysis criteria were sub-elements of two subject competencies. Seven sub-elements were derived from each competency. Frequency analysis was performed to determine how often the sub-elements were reflected in the activity tasks. The results were as follows. First, with regard to the sub-elements of 'practical problem-solving capability', 'value judgment' was reflected most frequently in the activity tasks followed by 'exemplification of solution', 'logical thinking', 'critical thinking', 'decision-making', 'practical reasoning', and 'evaluation of solutions'. Secondly, the sub-elements of 'independent life capability' were unevenly distributed in the activity tasks. The 'capability to perform conscious living' was reflected most frequently followed by 'development and self-identity', 'time, money, and leisure management', and 'reasonable consumption and resource utilization'. For teachers wanting to teach activity-oriented classes and student participatory classes, the results pinpoint the materials necessary to develop learners' subject competencies by using textbooks from different publishing companies.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.212-213
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• 2022

Recently, the construction industry is increasingly in need of securing safety rights due to repeated serious accident. Accordingly, the government enacted the "Serious accident Punishment Act" to strengthen punishment for serious accident and expand the scope of punishment. However, safety managers in the construction industry are still vulnerable to safety accidents due to the heavy workload. The purpose of this study is to increase the efficiency of performance tasks and reduce serious accidents in the construction industry through analysis of performance tasks by stages of construction projects. The tasks derived through domestic research and domestic and foreign system analysis were classified step by step to analyze the correlation between difficulty and preventive effect, and inefficient tasks were discovered and improved. This can be used as basic data for identifying safety management tasks and preparing effective safety prevention measures, and it is expected to be a preventive measure against industrial accidents in the construction industry by using it for efficient work reorganization by safety managers.

• Research in Mathematical Education
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• v.26 no.4
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• pp.291-310
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• 2023

In this paper, we propose a theoretical framework for Chinese high school mathematics teachers use new textbooks based on the work of Remillard (1999) and Chau (2014). Based on this framework, a multiple case approach was used to investigate how two high school mathematics teachers from Shanghai use new textbooks. The results suggest that in the curriculum mapping arena, both the novice teacher and the expert teacher often planned to appropriate the unit content, and sometimes planned to add supplemental content. When organizing the unit content, novice teacher always planned to follow the new textbook in sequence, while expert teacher often would follow the new textbook in sequence, but sometimes planned to rearrange the unit content. In the design arena, both the novice teacher and the expert teacher tended to appropriate the introduced tasks and definitions. The novice teacher often planned to appropriate the example problems and exercise problems, while the expert teacher often intended to flexibly use the example problems and exercise problems. In the construction arena, the novice teacher seldom adjusted the planned tasks; in contrast, the expert teacher adjusted the planned tasks more frequently. In the reflection arena, the novice teacher often thought she should improve the mathematics tasks, while the expert teacher almost always thought he needed to improve the mathematics tasks. The framework shown in this paper provides a tool to investigate how mathematics teachers use textbooks.

• Journal of Elementary Mathematics Education in Korea
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• v.21 no.2
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• pp.309-341
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• 2017

This study aims to investigate an approach to teach percentages in elementary mathematics class by analyzing calculating strategies with percentage the students use to solve the percentage tasks and their percentages of correct answers, as well as types of errors with percentages the students make. For this research 182 sixth graders were examined. The instrument test consists of various task types in reference to the previous study; the percentages tasks are divided into algebraic-geometric, part whole-comparison-change and find part-find whole-find percentage tasks. According to the analysis of this study, percentages of correct answers of students with percentage tasks were lower than we expected, approximately 50%. Comparing the percentages of correct answers according to the task types, the part-whole tasks are higher than the comparison and change tasks, the geometric tasks are approximately equal to the algebraic tasks, and the find percentage tasks are higher than the find whole and find part tasks. As to the strategies that students employed, the percentage of using the formal strategy is not much higher than that of using the informal strategy, even after learning the formal strategy. As an insightful approach for teaching percentages, based on the study results, it is suggested to reinforce the meaning of percentage, include various types of the comparison and change tasks, emphasize the informal strategy explicitly using models prior to the formal strategy, and understand the relations among part, whole and percentage throughly in various percentage situations before calculating.

• ETRI Journal
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• v.36 no.5
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• pp.704-713
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• 2014

Most natural language processing tasks depend on the outputs of some other tasks. Thus, they involve other tasks as subtasks. The main problem of this type of pipelined model is that the optimality of the subtasks that are trained with their own data is not guaranteed in the final target task, since the subtasks are not optimized with respect to the target task. As a solution to this problem, this paper proposes a consolidation of subtasks for a target task ($CST^2$). In $CST^2$, all parameters of a target task and its subtasks are optimized to fulfill the objective of the target task. $CST^2$ finds such optimized parameters through a backpropagation algorithm. In experiments in which text chunking is a target task and part-of-speech tagging is its subtask, $CST^2$ outperforms a traditional pipelined text chunker. The experimental results prove the effectiveness of optimizing subtasks with respect to the target task.

• Journal of Elementary Mathematics Education in Korea
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• v.19 no.3
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• pp.387-408
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• 2015

The purpose of this research is to analyze the mathematical tasks of length measurement in two different perspectives, the level of cognitive demands and learning trajectories, and restructure the mathematical tasks so that the students' conceptual learning is promoted and students are able to have opportunities to think more broadly. Ten lessons with the restructured mathematical tasks were implemented for a class of 2nd grade elementary students. Also a qualitative and in-depth study was conducted with 4 students of the target group. The study shows that firstly, the restructured tasks requiring high level of cognitive skills, had positive effects in increasing the students' level of thinking and reasoning. Secondly, the tasks modified according to the learning trajectories of Szilag, Clements & Sarama(2013) in length measurement, have proven to promote students' concept learning and elaborate the students' level of thinking.

• Journal of Elementary Mathematics Education in Korea
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• v.18 no.1
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• pp.83-103
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• 2014

The purpose of this paper is to find a method of measuring mathematical creativity reasonably. In the pursuit of this purpose, we designed four multiple solution tasks that consist of two kinds of open tasks; 'tasks with open solutions' and 'tasks with open answers'. We collected data by conducting an interview with a gifted fifth grade student using the four multiple solution tasks we designed and analyzed mathematical creativity of the student using Leikin's model(2009). Research results show that the mathematical creativity scores of two students who suggest the same solutions in a different order may vary. The more solutions a student suggests, the better score he/she gets. And fluency has a stronger influence on mathematical creativity than flexibility or originality of an idea. Leikin's model does not consider the usefulness nor the elaboration of an idea. Leikin's model is very dependent on the tasks and the mathematical creativity score also varies with each marker.

• The Journal of the Korea Contents Association
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• v.19 no.4
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• pp.197-206
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• 2019

This study aims to analyze through the integrated textbooks whether writing tasks are designed to be successful in cultivating students' writing abilities in the general-purpose Korean language education. First, we established the concept and the components of the writing task based on the definitions mentioned in previous research. The analysis of the types of writing tasks revealed "free writing" and "imitation and writing" to be the most frequent types of writing tasks in both textbooks. The textbooks have only twenty-one subjects in common. And most instructions provide only themes and genres, excluding the purpose, form, quantity, and time necessary for the article or for comprehending the instructions. In these tasks, the reading passages are most often explanatory text. The scoring criteria and time were not provided for the evaluation criteria and other factors. Therefore it became necessary to express the components of the writing task as explicitly and concretely as possible to improve learners' performances.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.2
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• pp.9-15
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• 2012

The purpose of this study was to investigate the effects of the secondary tasks such as sending text message (STM) and searching navigation (SN) on skin conductance level (SCL) and driving performance of relatively aged and high-experienced drivers. The subjects included 26 taxi drivers; 12 males aged $56.3{\pm}4.4$ with $28.4{\pm}6.4$ years of driving experiences and 14 females aged $55.5{\pm}3.5$ with $19.4{\pm}5.0$ years of driving experiences. All subjects were instructed to keep a constant following distance (30m) from the car ahead and a given vehicle speed (80km/h or 100km/h) in a driving simulator. The relative change of SCL, vehicle velocity deviations, and average following distances were measured during driving only and driving with secondary tasks. The relative change of SCL, average following distance, and vehicle velocity deviation were more increased during the driving with secondary tasks than driving only. The relative change of SCL, vehicle velocity deviation, and average following distance were more affected by driving with 100km/hr than 80km/hr of a given vehicle speed. Secondary tasks increased a work load of drivers in term of SCL change, and decreased driving performance in terms of the vehicle velocity deviation and average following distance.