• Journal of Korean Society for Atmospheric Environment
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• v.33 no.5
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• pp.435-444
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• 2017

In this study, we investigated the effect of aerosol feedback on $PM_{10}$ simulation using a two-way coupled air quality model (WRF-CMAQ). $PM_{10}$ concentration over Korea in January 2014 was simulated, and the aerosol feedback effect on the simulated solar radiation was intensively examined. Two $PM_{10}$ simulations were conducted using the WRF-CMAQ model with (FB) and without(NFB) the aerosol feedback option. We find that the simulated solar radiation in the west part of Korea decreased by up to $-80MJ/m^2$ due to the aerosol feedback effect. The feedback effect was significant in the west part of Korea, showing high $PM_{10}$ estimates due to dense emissions and its long-range transport from China. The aerosol feedback effect contributed to the decreased rRMSE(relative Root Mean Square Error) for solar radiation (47.58% to 30.75%). Aerosol feedback effect on the simulated solar radiation was mainly affected by concentration of $PM_{10}$. Moreover, FB better matched the observed solar radiation and $PM_{10}$ concentration than NFB, implying that taking into account the aerosol direct effects resulted in the improved modeling performance. These results indicate that aerosol feedback effects can play an important role in the simulation of solar radiation over Korean Peninsula.

• Journal of the Korean School Mathematics Society
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• v.8 no.2
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• pp.249-271
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• 2005

The study was aimed to show effects of the newly step branch's feedback models on the mathematics underachievers' mathematics achievement and attitude toward the mathematics, extent of self-check. The subject are 26 mathematics underachievers in the End grade of H middle school located in Taejeon. They were divided into an experimental group and a control group, and the attribution disposition. Experiment group was provided step branch's feedback and control group was provided general formative' feedback. The duration of the treatment was over a period of six weeks. The result of study, the step branch's feedback was effects for increasing he mathematics achievement and attitude toward the mathematics than the general formative' feedback(p<.05). In addition, the step branch's feedback group had better extent of self-check than the general formative' feedback.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.3
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• pp.120-131
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• 2017

Recent studies have suggested that providing in-vehicle feedback on various driving behaviors promote eco-friendly driving behaviors. However, there was relatively little interest in cognitive overload that can be caused by the provision of information. Thus, the goal of this study was to investigate the relative effects of two types of feedback(visual feedback vs. visual-auditory feedback) to increase eco-driving performance while minimizing driving workload. Also, in this study, the complexity of the driving task was distinguished (secondary vs. tertiary task) in order to reflect the actual driving situation. The study adopted a counterbalancing design in which the two feedback types were delivered in a different order under the two different task conditions. Results showed that providing the visual-auditory feedback was more effective than the visual only feedback in both promoting eco-friendly driving behaviors and minimizing driving workload under both task conditions.

• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.15-20
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• 2018

This study aimed to find an effective intervention measure through establishing the correlation between self-regulation (control over life style) and height growth through neuro-feedback training. 40 elementary students in grades two to four with height growth programs (20 experimental group students, 20 control group students) were examined for the changes before and after undergoing neuro-feedback training. The experiment lasted for three months with one 30-minute training session two times a week. After analyzing the differences in self-regulation among the control group with no neuro-feedback training and the experimental group with neuro-feedback training, the differences in height growth were analyzed. First of all, there were positive changes in self-regulation of the experimental group compared with the control group. Secondly, the experimental group showed larger changes in height growth. In conclusion, neuro-feedback training had positive effects upon the self-regulation that adjusts the acquired factors of height growth, which led to positive effects.

• Physical Therapy Rehabilitation Science
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• v.1 no.1
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• pp.13-16
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• 2012

Objective: Electroencephalogram (EGG)-feedback is a training procedure aimed at altering brain activity, and is used as a treatment for disorders like attention. The purpose of this study was to determine the effects of external focus of attention by EGG-feedback on balance in young adults. Design: Cross-sectional study. Methods: Subject were students in Sahmyook University. Fifty young adults in their twenties and thirties. Subjects were performed both with and without external focus of attention by EEG-feedback on the posture of standing and tandem standing. Participants were educated effort to maintain static posture when they were under internal focus of attention. Good Balance System was used for measurement of postural consistency upon the following force platforms. Results: Body sway decreased significantly both normal standing and tandem standing with external focus of attention by EEG-feedback (p<0.05). Conclusions: The results demonstrate that the benefits of an external attentional focus are generalizable to young adults. The external focus of attention outperformed the internal focus of attention on the postural balance (p<0.05). It is showed that external focus of attention significant effects on balance by revoked automatic postural control of movement. Furthermore balance might be improved by training with an external focus. Further study is required to develop for training as a method of preventing fall in elderly peoples.

• Journal of International Academy of Physical Therapy Research
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• v.4 no.2
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• pp.552-556
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• 2013

The purpose of this study is to examine the effects of feedback breathing exercise on respiratory muscle activity. Thirty stroke patients were randomly and equally assigned to an experimental group and a control group. The experimental group received rehabilitation exercise treatment for 30 minutes and feedback respiratory exercise for 30 minutes and the control group received rehabilitation exercise treatment for 30 minutes and conducted motomed exercise for 30 minutes. All of them conducted exercises five times per week for four weeks. Respiratory muscles including the upper trapezius(UT), longissimus dorsi(LD), rectus abdominis(RA), external abdominal oblique(EAO) and, internal abdominal oblique(IAO) were measured using MP 150WSW prior to and after the experiment. Regarding pulmonary functions prior to and after the experiment, the experimental group showed significant differences in all sections but the control group did not show significant differences in any sections. As for in-between group differences after the experiment, there were significant differences in the UT, LD, RA, and IAO but no significant differences in the EAO. In conclusion, respiratory muscle activity was more effective for the experimental group than the control group. It is considered that feedback respiratory exercise may induce improvement in respiratory muscles in stroke patients through feedback breathing exercise.

• Journal of the Korean Society of Physical Medicine
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• v.6 no.1
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• pp.9-17
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• 2011

Purpose : The purpose of this study was to compare the effects of performing feedback vs repeative tasks on lower extremity motor function and falls efficacy in chronic hemiplegic patients. Methods : 40 hemiplegic patients took part in this study. The average age of the feedback-task group was 68.45 years and 68.20 in the repeative-task group. All subjects participated in the study for 8 weeks, doing exercises 3 per day per week. All participants were assessed by using the Berg balance scale (BBS), the lower-extremity subscale of the Fugel-Meyer assessment of sensorimotor impairment (FMLE), and the falls efficacy scale (FES). The data were analyzed using a paired t-test. Results : After 8 weeks of exercise training, the results of this study were: the BBS and FMLE of hemiplegic patients showed a feedback-task and repeative-task groups (p<0.05). The FES of hemiplegic patients also showed a significant difference between the quantitative-task and qualitative-task groups (p<0.05). Conclusion : We present findings suggesting that chronic hemiplegic patients could improve their standing balance ability better through a feedback-task exercise program, as opposed to a repeative-task exercise program.

• The Journal of Korean Physical Therapy
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• v.19 no.6
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• pp.37-41
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• 2007

Purpose: Hemiplegic patients usually present with difficulties in maintaining their balance. Balance retraining is a major component of a rehabilitation program for patients with neurological impairments. This study compared the effects of prorpioceptive exercise and visual feedback program on the limits of stability (LOS) in chronic hemiplegia patients. Methods: Thirty subjects (mean age $57.0{\pm}9.8$) were recruited. The subjects were divided into a proprioceptive group and a visual group. The subjects for the proprioceptive group participated in the proprioceptive exercise program for 4 weeks, and the visual group were treated with visual feedback training using a Balance Master. Results: At the 4 week follow-up test, the LOS in the proprioceptive group improved significantly in all directions (p<0.05). However, improvement was only observed in the forward direction in the visual feedback group. Therefore, the proprioceptive control approach improves the LOS in chronic hemiplegia patients. Conclusion: These results suggest that compared with physical therapy alone using a proprioceptive control approach to hemiplegia, there was no additional benefit of visual feedback training, such as Balance Master, when administrated in combination with other physical therapy interventions.

• The Journal of the Korean dental association
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• v.58 no.11
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• pp.670-682
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• 2020

This research examined the difference in cognitive load and the virtual presence depending on auditory feedback and task difficulty in haptic-based dental simulation. In the field of dental education, practice-centered training using handpiece has been crucial because a practitioner's psychomotor experience has a significant impact on the mastery of treatment skills. For the novice, it is necessary to reduce errors in dental treatment to enhancing skill acquisition in the haptic practice. In the training process, the force-feedback is crucial to elaborate subtle movement to guide what to do and how it should be hard or soft. However, It is not easy to add force-feedback to generate kinetic experience training. As an alternative method, we examined that auditory feedback can help learners' skill training. In this study, we analyzed how the presence/absence of auditory feedback at the different levels of task difficulty impacts learners' psychological demand and virtual presence in the virtual reality simulation. For this study, 29 dental college students participated in a dental simulation. The participants were grouped into two conditions that are with and without auditory feedback. Additionally, two consecutive tooth preparation tasks with different levels of difficulty were used in the simulation. The auditory feedback condition gives alarms to a learner when he treats a non-targeted tooth with a virtual handpiece. The user's cognitive load and virtual presence were measured to examine the effects of auditory feedback. The results revealed that the main effect was found in cognitive loads. Also, a significant interaction effect was shown in the virtual presence. We discussed the effective design methods for the virtual reality-based dental simulation through the result of this study.

• The Journal of Korean Association of Computer Education
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• v.5 no.3
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• pp.59-67
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• 2002

In this study, we have designed and established a formative evaluation system which provides the web-based corrective feedback in the current situation that the importance of feedback as well as the formative evaluation is getting highlighted in the course of learning and instruction. This system is composed of three types of corrective feedback. The first one is the informations providing feedback by stage. It provides the explanations or the correct answers-related informations for the wrong answered questions by stage and directly. The second one is the error corrective feedback, which provides the informations about the reasons of the errors on each wrong answered question so that the learner can correct his errors. Lastly, the corrective feedback by the accumulated marks shows the learner's total marks and their wrong answered questions to enable the learner to learn for themselves. We analyzed how these three corrective feedback effects on the learning achievement after applying them to learners, and testified the type of the most effective corrective feedback in enhancing the degree of learning achievement.