• Korean Journal of Child Studies
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• v.38 no.3
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• pp.75-90
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• 2017

Objective: This study aimed to identify children's cognitive processing and performance characteristics while multiple task performance. It confirmed whether their multiple task performance and psychological refractory period (PRP) varied by task condition (stimulus onset asynchrony [SOA] and task difficulty) and stimulus modality. Methods: Seventy 5-year-olds were recruited. Multi-task tools were developed using the E-prime software. The children were required to respond to two stimuli (visual or auditory) presented with microscopic time difference and their response times (RTs) were recorded. Results: As the SOA increased, the RTs in the first task increased, while the RTs in the second task and PRP decreased. The RTs of the first and second tasks, and the PRP for difficult tasks, were significantly longer than those for easy tasks were. Additionally, there was an interaction effect between the SOA and task difficulty. Although there was no main effect of stimulus modality, task difficulty moderated the modality effect. In the high difficulty condition, the RTs of the first and second tasks and PRP for the visual-visual task were significantly longer than those for auditory-auditory task were. Conclusion: These results inform theoretical discussions on children's multi-task mechanism, and the loss of multiple task performance. Additionally, they provide practical implications and information on the composition of multi-tasks suitable for children in educational environments.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.2
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• pp.83-91
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• 2016

PURPOSE: The purpose of this study was to determine the efficacy of dual-task action observation training (AOT) and single-task AOT related with daily living task on walking ability and ADL performance in chronic stroke patients. METHODS: Twenty-seven chronic stroke subjects were included in the study. They were randomly assigned to three task categorieds as follows: whole dual-task AOT or partial dual-task AOT or single-task AOT rehabilitation. Whole dual-task AOT observed the movement at once and partial dual-task AOT observed the movement divided into 4 parts related functional gait and activities of daily living task for 2 minutes 30 seconds. Single-task AOT observed the movement related functional gait for 2 minutes 30 seconds. Both groups had physical training session for 12 minutes 30 seconds. The study was conducted for four weeks, with three training sessions a week, for twelve weeks. All subjects were evaluated for their walking ability and activities of daily living through devices, 10m walking test (10MWT), dynamic gait index (DGI), and Korea-Modified Barthel Index (K-MBI). RESULTS: A significant improvement of walking ability and ADL performance happened among dual-task AOT subjects, compared with a single-task AOT subjects, during the 4-weeks course treatment. The results of the study showed statistically significant differences in 10MWT (p<0.05) and DGI (p<0.05), and K-MBI (p<0.05). CONCLUSION: Our results indicated that dual-task AOT has a positive additional impact on recovery of walking ability and ADL performance in chronic stroke patients.

• Journal of the Korean Society of Safety
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• v.16 no.4
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• pp.168-174
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• 2001

For human error analysis, the structure and situation of a task should be analyzed in advance. The paper introduces Structured Information Analysis (SIA) as a task analysis method for error analysis, and delineates the result of application on the emergency procedure of Korean Standard Nuclear Plants (KSNPs). From the task analysis about emergency procedure of KSNP, total 72 specific task goals were identified in the level of system function, and 86 generic tasks were classified from the viewpoint of physical sameness of the task description. Human errors are dependent on task types so that the result of task analysis would be used as a basis for the error analysis on the emergency tasks in nuclear power plants.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.7
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• pp.3566-3582
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• 2019

In intelligent warehouse picking system, the allocation of tasks has an important influence on the efficiency of the whole system because of the large number of robots and orders. The paper proposes a method to solve the task allocation problem that multi-robot task allocation problem is transformed into transportation problem to find a collision-free task allocation scheme and then improve the capability of task processing. The task time window and the power consumption of multi-robot (driving distance) are regarded as the utility function and the maximized utility function is the objective function. Then an integer programming formulation is constructed considering the number of task assignment on an agent according to their battery consumption restriction. The problem of task allocation is solved by table working method. Finally, simulation modeling of the methods based on table working method is carried out. Results show that the method has good performance and can improve the efficiency of the task execution.

• The Journal of Korean Physical Therapy
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• v.27 no.5
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• pp.364-368
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• 2015

Purpose: Walking in the dual-task condition is a critical skill for hemiplegic patients to live in real-life situations. The purpose of this study was to compare the effect of dual-task gait training and general gait training on gait parameters and cognitive function in patients with chronic stroke during dual-task walking. Methods: The study included 23 patients with chronic hemiparetic stroke who were randomly divided into experimental (dual-task gait training) and control (general walking training) groups. The 11 subjects in the experimental group and nine subjects in the control group received dual-task gait training (walking while handling a ball, crossing obstacles, picking up various objects, and problem solving simple cognitive tasks and general over-ground gait training, respectively, for 30 minutes per day 5 days per week for 4 weeks. Spatiotemporal parameters and cognitive tasks in the dual-task gait condition were measured. Statistical analysis of the changes between the pre- and post-intervention measurement variables was performed using ANCOVA. Results: In the gait condition under cognitive tasks, the changes pre- and post-intervention in gait velocity, stride length, double support limb, and step symmetry were significantly greater in the dual-task gait training group; however, the dual-task gait training group showed no significant improvement compared to the general gait training group in terms of the assessment of cognitive tasks. Conclusion: The findings suggest that dual-task gait training may be beneficial for walking ability in dual-task walking condition.

• Journal of Computing Science and Engineering
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• v.4 no.3
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• pp.189-206
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• 2010

It is generally accepted that dynamic voltage scaling (DVS) is one of the most effective techniques of energy minimization for real-time applications in embedded system design. The effectiveness comes from the fact that the amount of energy consumption is quadractically proportional to the voltage applied to the processor. The penalty is the execution delay, which is linearly and inversely proportional to the voltage. According to the granularity of tasks to which voltage scaling is applied, the DVS problem is divided into two subproblems: inter-task DVS problem, in which the determination of the voltage is carried out on a task-by-task basis and the voltage assigned to the task is unchanged during the whole execution of the task, and intra-task DVS problem, in which the operating voltage of a task is dynamically adjusted according to the execution behavior to reflect the changes of the required number of cycles to finish the task before the deadline. Frequent voltage transitions may cause an adverse effect on energy minimization due to the increase of the overhead of transition time and energy. In addition, DVS needs to be carefully applied so that the dynamically varying chip temperature should not exceed a certain threshold because a drastic increase of chip temperature is highly likely to cause system function failure. This paper reviews representative works on the theoretical solutions to DVS problems regarding inter-task DVS, intra-task DVS, voltage transition, and thermal-aware DVS.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.730-730
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• 2004

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.729-729
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• 2004

• 월간산업보건
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• s.349
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• pp.51-70
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• 2017

• Journal of Digital Contents Society
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• v.14 no.1
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• pp.59-64
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• 2013

In this paper, we proposed low power algorithm for a task. The task means the inside of a necessary processor and external resources to work accomplishment of a system. Each task analyzes a life time and a number of called for implement a low power circuit. First of all, reduce power consumption of a task have maximum power consumption for low power circuit implementation. Therefore, first selecting a task had maximum power consumption. The task had a maximum power consumption ranking consider a life time and a number of called for each task. While a life time of task is long, top priority ranking to decrease power consumption to the task that the number of call generates the power consumption how a disguise is large in case of a lot of task becomes. Frequency decision to have minimum power consumption, and decrease power consumption all the circuit by a change of frequency of the task which the minimum task that a wasting past record is the maximum becomes. Also, keep continuously minimum power consumption, with every effort task until last life time in opening life time, and decrease gets total power consumption. Experiments results show reduction in the power consumption by 5.43% comparing with that [7] algorithm.