• Journal of Korean Institute of Industrial Engineers
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• v.37 no.3
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• pp.209-215
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• 2011

The objective of this study was to determine whether there are differences in hand muscle activities (APB : abductor pollicis brevis, ED : extensor digitorum, ECU : extensor carpi ulnaris, and EI : extensor indicis) and subjective discomfort according to the three mouse sizes (small, medium, large) and two task types (pointing and scrolling). The mouse size and task type showed significant interaction effects on the total NEMG (p = 0.004) and on the NEMG of the abductor pollicis brevis muscle (p = 0.001). The total NEMG and the NEMG of APB showed the highest value in the 'scrolling' task using the 'small' mouse. However, the NEMG of the EI was different according to the mouse size, and the 'small' mouse showed the lowest value. The subjective discomfort was the lowest in the 'medium' mouse, and all nine subjects preferred the 'medium' size. The hand-size related anthropometric variables showed different correlations according to the task type and mouse size with the NEMGs and subjective discomfort. The results of this study could be used as a basic information for the determination of the proper mouse size according to the hand size.

• Journal of Biomedical Engineering Research
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• v.28 no.1
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• pp.55-65
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• 2007

This paper sought to investigate pupil size variability, pupil size parameters in terms of time domain and frequency domain, the autonomic activity change induced by posture change, degree of sleepiness and cognitive task (math task). With a specially designed pupil image acquisition system in the dark room, these three kinds of experiments were performed to induce a dominant state of sympathetic or parasympathetic activation. Electrocardiogram and pupil size were measured in all the experiments. Based on three experiments, we calculated heart rate variability. In the pupil size analysis, we calculated the mean and standard deviation of pupil size (in time domain), and proposed several frequency bands that exhibit different autonomic activation between different sessions. The results indicate that in terms of heart rate variability, posture change exhibited significant differences but not between sleepiness level, or between cognitive task. Pupil sizes differed only during the postures. And we found some frequency bands that correlated with autonomic activation in each experiment. While heart rate variability reflects posture change that need cardiac control, pupil size variability reflects not only posture induced autonomic activation but sleepiness and cognitive load, which is processed in the brain, in time and frequency domain parameter.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2008.10b
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• pp.479-491
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• 2008

A "task network" is a type of social network that consists of experts who exchange professional help and advice regarding executing tasks. In this study, we investigate the task network used within the IS department of a national bank in Korea. We identify how this network moderates the influence of computer-mediated communication (CMC) technology on an individual s task performance. Size, density, and centrality were measured as the characteristics of a personal task networks. Size equates to the total number of colleagues who work with a specific member for a certain project. Density is the ratio of the number of actual relationships to the total number of available relationships. Centrality defines whether an individual s position is in the exact center of whole network, and is measured by betweenness centrality, meaning the position one member holds between others in a network. Our findings conclude that the conditions - the larger the size of the task network, the smaller its density and the higher its level of centrality - lead to more benefits of using CMC media. Further, this positive effect of CMC is more noticeable when it provides synchronicity.

• Journal of the Ergonomics Society of Korea
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• v.29 no.4
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• pp.605-610
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• 2010

In order to design a touch interface for the elderly, human performance of input tasks on the touch screen was investigated by the laboratory experiment. Input times and input errors were measured in the experimental conditions that were changed according to age, key size, interkey space and input tool(finger or stylus pen). In the most of all experimental conditions, the task performance of the elderly was lower than that of the young. However, there were significantly different performance patterns between both groups. As the difficulty of task was getting higher, the task performance of the elderly was sharply decreased; pressing small key button by finger sharply increased input time and error rate, compared to that of the young. Therefore, the square key size suitable to the elderly may be over $8.0{\times}8.0mm$. While the interkey space did not influence to the input task performance of the young, the task performance of the elderly was influenced. The elderly showed big difference of task performance according to input tool. However, the young were less influenced by input tool.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.3
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• pp.83-88
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• 2020

With developing vehicle and communication technologies, cars can communicate with road-side infrastructures and among other cars. As autonomous driving cars have been developed, the cars are equipped with many sensors and powerful processing units. There are many studies related to provide cloud services to users by using available resources of connected cars. In this paper, we proposed a dynamic task size decision scheme that considers communication environment between a vehicle and a base station as well as available resources while allocating a proper task to each vehicle. Simulation results based on the proposed model show that a vehicle can complete its allocated task when we considers available resources and communication environments.

• Strategy21
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• s.39
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• pp.163-197
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• 2016

The completion of Jeju Naval Base on February 2016 made the Republic of Korea Navy(ROKN) review the size and role of the Maritime Task Flotilla(MTF). The new strategic environment for the 12st century and the new challenges require the Navy to counter North Korea's provocations and prevent potential enemy's threat. The Navy is also required to take part in the variety of international roles and missions commensurated with Korea's global status to maximize the national interest. Despite these changes, Korea's military construction concept is still unable to break away from the old paradigm of the North Korean threat largely centered. In order to develop the current MTF into the Task Group with the construction of Jeju Naval Base, the Navy must newly not only establish new force development plan and fleet management concepts but also go to persuade and convince policy decision makers. To this end, the following efforts should be promoted. First, the ROK Navy steps up efforts in order to share with the Task Group's vision and strategy. The Navy should also provide the size and structure as well as the missions and roles of the Task Group to react to new maritime security environment. Second, the Navy analyse the MTF's ability and what is required and necessary to perform its duty. After that, it must set out the direction of the Task Group's force development. Third, the current missions and roles of the MTF should be re-established to respond various threats. Finally, accommodating of new technology to the MTF should intensify its strengths. The ROK Navy has a mixed force structure consisting of three fixed- base fleets and a MTF. The fixed base fleet has a passive force to defend and protect its own sea areas, but the MTF should actively not only counter North Korea's threats, including ballistic missiles, but also fight potential threats and takes international missions as a primary task force. However, the MTF has a limited capability to accomplish given missions and long-range operations, and thus, the ROK Navy is strongly required to construct the Task Group.

• Journal of Korean Academy of Nursing Administration
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• v.21 no.3
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• pp.263-276
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• 2015

Purpose: The study was done to verify the effect size of the variables related to the emotional labor of nurses. Methods: A total of 47 article on variables related to the emotional labor of nurses and published from 2006 to 2014 were used for the meta-analysis. Results: Variables with the largest effect size related to emotional labor were identified as the variables of work task, organization and individual characteristics in descending order of effect size. The sub-factors with the greatest effect size in the work task variable were exhaustion and work commitment, while for organization variables, intention to change jobs had the largest effect size. For individual characteristics, physical symptoms had the largest effect size. Conclusion: The results of this study are meaningful as the first study to integrate research results on variables related to the emotional labor of Korean nurses, providing practical data for the management of emotional labor.

• Korean Journal of Child Studies
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• v.34 no.1
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• pp.21-34
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• 2013

The purposes of this study were (1) to investigate the differences in the level of children's knowledge and reasoning skills due to the sloping phenomenon according to their ages and the types of tasks they were asked to perform, and (2) to investigate whether children's prior knowledge is changed to post knowledge through their reasoning. A total of 120 subjects, forty from each of the age groups 4, 6 and 8 were selected for the study. The major findings are presented below : 8-year old children showed higher levels of prior knowledge than 6-year old children. The prior knowledge level of the "size" task was higher than that of the "weight" task. 6-and 8-year old children showed higher levels of reasoning than 4-year old children. The reasoning level of the "size" task was higher than that of the "weight" task. 6-and 8-year old children showed higher levels of post knowledge than 4-year old children. However, there was no difference in children's post knowledge according to task difference. Through the different types of reasoning involved in the children's performances of the two tasks, changes in the prior knowledge of the sloping phenomenon were observed among all age groups.

• Journal of Industrial Convergence
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• v.21 no.12
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• pp.101-111
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• 2023

This study conducted systematic review and meta-analysis to analyze the effectiveness of a dual-task for cognitive function in patients with MCI in Korea. A search was conducted using eight databases, and the search terms were MCI, cognition, and dual task. This study includes RCT and nonRCT published from January 2013 to July 2023. A total of 682 studies were searched, and 8 studies that fulfilled the inclusion and exclusion criteria were finally analyzed. Methodological quality was assessed with the RoB, RoBANS. The meta-analysis used CMA 4.0 ver. As a result of the analysis, the overall effect size of the dual task was medium effect size. The effect size according to the outcome variables was large for orientation and executive function, and medium effect size for global cognitive function, visuospatial function, memory, and attention. As a result of analysis according to the intervention period, the effect was greater when applied for 4 to 8 weeks, and the effect size was larger when applied for 24 to 30 sessions. This study presented clinical evidence on the effectiveness and application method of a dual-task applied to improve cognitive function in patients with MCI.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.38-52
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• 2018

This study examined the effect sizes of psychological burnout-related factors on the psychological burnout of early childhood teachers by applying meta - analysis focusing on master 's theses, doctoral dissertations and journals that have been published in Korea for the past 20 years. The results of the analysis are as follows. First, the total effect size, the factor group, the sub-factor, and the positive and negative effect factors of the inducing and inhibiting factors showed a significant effect size. Second, in terms of inducing factors, the task problem group showed a larger effect size than the negative relationship group. Third, among the lower factor of the negative relationship group, all the sub factors excluding the negative relationship with the director, effect size showed a medium effect size. Fourth, task stress showed the greatest effect size among the sub factors of the task factor group, followed by role conflict, task overload, and role ambiguity. Fifth, resilience showed the greatest effect size among the inhibition factors, followed by organizational support factor, teacher efficacy factor, social support factor, and emotional factor. Sixth, all sub factors of the emotional labor factor group, organizational support factor of the organizational support factor group, general teacher efficacy factor of the teacher efficacy factor group, and all sub factors of social support factor Medium effect size. In addition, the lower factor of all the other factors showed a large effect size. Seventh, of the effect factors, job satisfaction factor, depression factor, and turnover intention factor all showed a large effect size.