• International Journal of Aeronautical and Space Sciences
• /
• v.12 no.2
• /
• pp.163-174
• /
• 2011

Task assignments of multiple unmanned aerial vehicles (UAVs) are examined. The phrase "task assignment" comprises the decision making procedures of a UAV group. In this study, an on-line decentralized task assignment algorithm is proposed for an autonomous UAV group. The proposed method is divided into two stages: an order optimization stage and a communications and negotiation stage. A genetic algorithm and negotiation strategy based on one-to-one communication is adopted for each stage. Through the proposed algorithm, decentralized task assignments can be applied to dynamic environments in which sensing range and communication are limited. The performance of the proposed algorithm is verified by performing numerical simulations.

• International Journal of Computer Science & Network Security
• /
• v.23 no.3
• /
• pp.31-48
• /
• 2023

The popularization of smart devices and subsequent optimization of their sensing capacity has resulted in a novel mobile crowdsensing (MCS) pattern, which employs smart devices as sensing nodes by recruiting users to develop a sensing network for multiple-task performance. This technique has garnered much scholarly interest in terms of sensing range, cost, and integration. The MCS is prevalent in various fields, including environmental monitoring, noise monitoring, and road monitoring. A complete MCS life cycle entails task allocation, data collection, and data aggregation. Regardless, specific drawbacks remain unresolved in this study despite extensive research on this life cycle. This article mainly summarizes single-task, multi-task allocation, and space-time multi-task allocation at the task allocation stage. Meanwhile, the quality, safety, and efficiency of data collection are discussed at the data collection stage. Edge computing, which provides a novel development idea to derive data from the MCS system, is also highlighted. Furthermore, data aggregation security and quality are summarized at the data aggregation stage. The novel development of multi-modal data aggregation is also outlined following the diversity of data obtained from MCS. Overall, this article summarizes the three aspects of the MCS life cycle, analyzes the issues underlying this study, and offers developmental directions for future scholars' reference.

• Therapeutic Science for Rehabilitation
• /
• v.1 no.2
• /
• pp.14-22
• /
• 2012

Introduction : The purpose of scholarly paper is to review of motor learning concepts and to examine in integration of motor learning research finding in occupational therapy services for adults with hemiplegia. Body : The principles of motor learning is stage of learning, type of task, practice and feedback. Depending on stage of learning, therapist need to apply of the principles. In early stage of learning, therapists should be promote patient's awareness about therapeutic goals, task performance environment and how to perform. Whole practice, blocked practice and constant practice improve performance skill. In the latter stage of learning, therapists have to design a intervention protocol for patient to use the implicit feedback. Random practice and open task facilitates performance skills. Conclusion : When establishing the a intervention plan for adults with hemiplegia, therapists should systematically developed the principles of motor learning. Intervention program must be established by applying the principles of motor learning in accordance with the learner's level of task performance, and modified depending on the therapeutic progress.

• School Mathematics
• /
• v.3 no.2
• /
• pp.325-354
• /
• 2001

The study aims to develop balanced performance assessment tasks for primary school mathematics which can be implemented in the primary school easily. In order to these purposes, I suggest the types of performance assessment tasks and the framework of assessment standards for the balanced performance assessment with describing the procedures of developing tasks and rubrics. The types of task are journal writing, problem posing, constructed task, and descriptive task. In the framework of assessment standards, I suggest holistic scoring which are classified as four levels according to the degree of excellence which students perform totally concerning about the criterion of implication, reasoning, accuracy, and communication. Also I analyse the responses of children to the task “make a beautiful pattern” and suggest its assessment rubric and anchor papers for each level for illustrating the process of developing a rubric in holistic scoring. In order to reflect the viewpoints of children and their Parents concerning about the tasks, the responses in self assessment and parent assessment are analysed. Finally, methods of implementing the assessment tasks and considerations are discussed.

• Korean Journal of Child Studies
• /
• v.2
• /
• pp.1-16
• /
• 1981

This study had two purposes. First, to examine the stages and developmental order of object permanence based on Piaget's theory. Second, to assess the effects of delay, attentiveness, and direction of gaze. Two experiments were conducted to examine the object permanence development in infants. The subjects for the 2 experiments were randomly drawn from a well-baby clinic. The subjects for Experiment 1 were 72 infants, 12 each in 6 age levels : 6, 9, 12, 15, 18, and 21 months old. Experiment 1 was designed to examine the stages and developmental order of object concept development, ana infants received 5 tasks as follows : (1) finding an object partially hidden under one box (2) finding an object completely hidden under one box (3) finding an object after successive visible displacements (4) finding an object after one invisible displacement (5) finding an object after successive invisible displacements. The subjects for Experiment 2 were 24 9-month-olds. Experiment 2 was designed to assess the effects of delay, attentiveness, and direction of gaze for Stage IV of object concept development. Subjects were equally assigned into one of two delay groups: 0-sec delay and 3-sec delay. Attentiveness was rated in terms of a three-point scale, and then divided into high and low attentive groups. Direction of gaze was judged into two directions. In two experiments, infants received three trials of task, and received a score of 0, 1, 2 for each trials. Data were analyzed by ANOVA, Tukey test, and t-test for task performance, and direction of gaze was analyzed by chi-square. The results obtained from two experiments were as follows : 1. In object permanence test, subjects obtained significantly higher scores with age, and 6, 9, 12, 18 months were classified into different developmental stages. 2. In object permanence development, subjects received significantly different scores with task and a developmental order of tasks was found. First of all, infants mastered finding an object partially hidden under one box, and then mastered finding an object completely hidden under one box. Contrary to Piagetian theory, in this study, the development of finding an object after successive visible displacements and finding an object after one invisible displacement were sometimes reversed. Finally, finding an object after successive invisible displacements was mastered, and the concept of object permanence was completed. 3. In Stage IV of object concept development, a 3-sec delay did not significantly affect the performance of tasks. The O-sec delay group didn't perform significantly better than the 3-sec delay group. 4. In Stage IV of object concept development, attentiveness of infants significantly affected the performance of task. So the highly attentive infants obtained better performance scores than the low attentive infants. 5. In Stage IV of object concept development, direction of gaze significantly affected the performance of task. That is, infants who gazed at the box which contained the object showed a higher rate of success than infants who gazed at the box which had already displaced the object.

• Journal of the Korean Society for Precision Engineering
• /
• v.22 no.1
• /
• pp.193-198
• /
• 2005

Changes in visuospatial cognitive performance, blood oxygen saturation and heart rate due to the highly concentrated oxygen administration were observed in this study. Six male ($25.8 \pm$1.0) and six female (($23.8 \pm$ 1.9) adults were asked to perform 20 visuospatial tasks with the same level of difficulties by supplying two different oxygen levels (21%, 30%). Experiment consisted of Rest1 (1 min.), Control (1 min.), Task (4 min.), and Rest2 (4 min.) and physiological signals such as blood oxygen saturation and heart rate were measured through each stage. The result showed the accuracy of task performance increased significantly at 30% oxygen concentration compared with 21%, which means oxygen supply has positive effects on visuospatial cognitive performance. When 30% oxygen was supplied, blood oxygen saturation during control and task phases was increased and heart rate was decreased compared with 21%. It means that 30% oxygen can stimulate brain activities by directly increasing the actual level of blood oxygen concentration during cognitive performance, and enough oxygen supply during cognitive performance make heart rate decrease.

• Korean Management Science Review
• /
• v.5 no.1
• /
• pp.29-44
• /
• 1988

In spite of user's participation affecting the success of the MIS project, many empirical studies, however have led to inconsistent results. This research was conducted to find the factors affecting user's participation, and the relationships between user's participation and MIS performance. To identify these problems, 43 systems operated with MIS among industries were surveyed based upon questionnaires and the personal interviews. The major findings of this study are as follows: First, the main factors affecting the user's participation out to be the MIS manager's attitude, the user manager's expectation, the MIS education and the character of user's task among 28 factors and these factors are different from stage to stage in MIS development. Second, each MIS development stage shows the different relationship between user's participation and MIS performance.

• Journal of Multimedia Information System
• /
• v.5 no.4
• /
• pp.291-297
• /
• 2018

Performance measurement is not an easy task. However, it is necessary to measure the expected value of the informatization project to be invested, to help the successful progress of the informatization project, and to confirm the result of the informatization project. This study describes the evaluation systems of the defense informatization project in Korea used after the end of the informatization project (post-implementation evaluation stage). In the post-implementation evaluation stage of proposed system, the informatization project is evaluated in terms of performance achievement, project plan compliance, project management, and economic validity. For each element, this study suggests metrics and practical measurement method. With metrics and their method, it can be evaluated which project is better than others. Moreover, the lessons learned can be developed. Under scarce budget condition, defense organizations can make better performance from IT project with the evaluation system suggested in this study.

• Korean Journal of Child Studies
• /
• v.20 no.3
• /
• pp.259-273
• /
• 1999

This studied investigated children's music identification, classification, and seriation cognitive task performance abilities by age and sex. The subjects were l20 six-, eight-, and ten-year-old school children. There were significant positive correlations among music cognition tasks and significant age and sex differences within each of the music tasks. Ten-year-old children were more likely to complete their music identification tasks than the younger children and girls were more likely than boys to complete their music identification tasks. Eight- and 10-year-old children were more likely to complete their music classification tasks than the younger group. Piagetian stage theory was demonstrated in children's music classification task performance. There was an age-related increase in the performance of the music seriation tasks. Developmental sequential theory was demonstrated in music seriation performance.

• Educational Technology International
• /
• v.13 no.1
• /
• pp.79-100
• /
• 2012

The focus of this research is on identifying the problems that learners experience during online problem-based learning (e-PBL) from a cognitive perspective. The study is concentrated on learners' cognitive load level at each stage of e-PBL. The research questions are specifically as follows: What is the level of cognitive load at each stage of e-PBL and what is the relationship between cognitive load and group performance? What cognitive difficulties are experienced by learners in e-PBL and what causes cognitive difficulties? In this study, we found that cognitive load was the highest in stage 1 and there was negative relationship between cognitive load at stage 1 and group performance. In addition, learners experienced difficulties during e-PBL such as the complexity of task, the difficulty in collaboration, and the lack of appropriate references. For further study, we will investigate some strategies regarding adjusting learners' cognitive load in the early stages of e-PBL.