• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.12
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• pp.2349-2356
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• 2008

In this paper, we present the method to effectively extract and classify the EEG caused by only brain activity when a normal subject is in a state of mental activity. We measure the synchronous EEG on the auditory event when a subject who is in a normal state thinks of a specific task, and then shift the baseline and reduce the effect of biological artifacts on the measured EEG. Finally we extract only the mental task signal by averaging method, and then perform the recognition of the extracted mental task signal by computing the AR coefficients. In the experiment, the auditory stimulus is used as an event and the EEG was recorded from the three channel $C_3-A_1$, $C_4-A_2$ and $P_Z-A_1$. After averaging 16 times for each channel output, we extracted the features of specific mental tasks by modeling the output as 12th order AR coefficients. We used total 36th order coefficient as an input parameter of the neural network and measured the training data 50 times per each task. With data not used for training, the rate of task recognition is 34-92 percent on the two tasks, and 38-54 percent on the four tasks.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.266-274
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• 2021

Ship officers are subject to excessive job stress, which has negative physical and psychological impacts and may adversely affect the smooth supply and demand of human resources. In this study, a mobile web application was developed as a tool for systematic job stress measurement and management of officers and verified through quality evaluation. Requirement analysis was performed by ship officers and staff in charge of human resources of shipping companies, and the results were reflected in the application configuration step. The application was designed according to the waterfall model, which is a traditional software development method, and functions were implemented using JSP and Spring Framework. Performance evaluation on the user interface, confirmed that proper input and output results were implemented, and the respondent results and the database were configured in the administrator interface. The results of evaluation questionnaires for quality evaluation of the interface based on ISO/IEC 9126-2 metric were significant 4.60 for the user interface and 4.65 for the administrator interface in a 5-point scale. In the future, it is necessary to conduct follow-up research on the development of data analysis system through utilization of the collected big-data sets.

• Korean Journal of Radiology
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• v.24 no.6
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• pp.541-552
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• 2023

Objective: Detection of pneumoperitoneum using abdominal radiography, particularly in the supine position, is often challenging. This study aimed to develop and externally validate a deep learning model for the detection of pneumoperitoneum using supine and erect abdominal radiography. Materials and Methods: A model that can utilize "pneumoperitoneum" and "non-pneumoperitoneum" classes was developed through knowledge distillation. To train the proposed model with limited training data and weak labels, it was trained using a recently proposed semi-supervised learning method called distillation for self-supervised and self-train learning (DISTL), which leverages the Vision Transformer. The proposed model was first pre-trained with chest radiographs to utilize common knowledge between modalities, fine-tuned, and self-trained on labeled and unlabeled abdominal radiographs. The proposed model was trained using data from supine and erect abdominal radiographs. In total, 191212 chest radiographs (CheXpert data) were used for pre-training, and 5518 labeled and 16671 unlabeled abdominal radiographs were used for fine-tuning and self-supervised learning, respectively. The proposed model was internally validated on 389 abdominal radiographs and externally validated on 475 and 798 abdominal radiographs from the two institutions. We evaluated the performance in diagnosing pneumoperitoneum using the area under the receiver operating characteristic curve (AUC) and compared it with that of radiologists. Results: In the internal validation, the proposed model had an AUC, sensitivity, and specificity of 0.881, 85.4%, and 73.3% and 0.968, 91.1, and 95.0 for supine and erect positions, respectively. In the external validation at the two institutions, the AUCs were 0.835 and 0.852 for the supine position and 0.909 and 0.944 for the erect position. In the reader study, the readers' performances improved with the assistance of the proposed model. Conclusion: The proposed model trained with the DISTL method can accurately detect pneumoperitoneum on abdominal radiography in both the supine and erect positions.

• Korean Journal of Radiology
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• v.24 no.5
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• pp.454-464
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• 2023

Objective: We aimed to investigate current expectations and clinical adoption of artificial intelligence (AI) software among neuroradiologists in Korea. Materials and Methods: In April 2022, a 30-item online survey was conducted by neuroradiologists from the Korean Society of Neuroradiology (KSNR) to assess current user experiences, perceptions, attitudes, and future expectations regarding AI for neuro-applications. Respondents with experience in AI software were further investigated in terms of the number and type of software used, period of use, clinical usefulness, and future scope. Results were compared between respondents with and without experience with AI software through multivariable logistic regression and mediation analyses. Results: The survey was completed by 73 respondents, accounting for 21.9% (73/334) of the KSNR members; 72.6% (53/73) were familiar with AI and 58.9% (43/73) had used AI software, with approximately 86% (37/43) using 1-3 AI software programs and 51.2% (22/43) having up to one year of experience with AI software. Among AI software types, brain volumetry software was the most common (62.8% [27/43]). Although 52.1% (38/73) assumed that AI is currently useful in practice, 86.3% (63/73) expected it to be useful for clinical practice within 10 years. The main expected benefits were reducing the time spent on repetitive tasks (91.8% [67/73]) and improving reading accuracy and reducing errors (72.6% [53/73]). Those who experienced AI software were more familiar with AI (adjusted odds ratio, 7.1 [95% confidence interval, 1.81-27.81]; P = 0.005). More than half of the respondents with AI software experience (55.8% [24/43]) agreed that AI should be included in training curriculums, while almost all (95.3% [41/43]) believed that radiologists should coordinate to improve its performance. Conclusion: A majority of respondents experienced AI software and showed a proactive attitude toward adopting AI in clinical practice, suggesting that AI should be incorporated into training and active participation in AI development should be encouraged.

• Science of Emotion and Sensibility
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• v.12 no.3
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• pp.341-350
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• 2009

Archer's capability of attention and relaxation control during shooting process was evaluated using EEG technology. Attention and meditation algorithms were used to represent the levels of mental concentration and relaxation levels. Elite, mid-level, and novice archers were tested for short and long distance shootings in the archery field. Single channel EEG was recorded on the forehead (Fp1) during the shooting process, and attention and meditation levels were computed by real time. Four types of variations were defined based on the increasing and decreasing patterns of attention and meditation levels during shooting process. Elite archers showed increases in both attention and relaxation while mid-level archers showed increased attention but decreased relaxation. Elite archers also showed higher levels of attention at the release than mid-level and novice archers. Levels of attention and relaxation and their variation patterns were useful to categorize archers and to provide feedback in training.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.10 no.1
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• pp.43-46
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• 2014

Cerebral Palsy is a genetic term referring to abnormalities of motor control caused by damage to a child's brain early in the course of development. Due to the impairment of balanced perioral muscle development, the prevalence of malocclusions in patients with cerebral palsy such as maxillary protrusion is high. But most clinicians may feel uncomfortable to treatment of these problems. Here a case report about mitigation of maxillary anterior teeth protruded in patient with cerebral palsy. 8y 4m old boy who have cerebral palsy visited our dental hospital. He showed severely protrusive maxillary anterior teeth with mouth breathing and could not close his mouth. He and his mother wanted to improve dental and facial esthetic problem. Specially designed or modified intraoral fixed appliance and rubber elastic chain was used in the therapy. Treatment carried out for 8 months and we could observe maxillary incisor angle was improved and mouth breathing habit was stopped. In conclusion, modified fixed appliance therapy for the patients with cerebral palsy might be useful. Continuous rehabilitation training of lips should be followed after treatment to correct imbalance of muscle tone.

• Physical Therapy Korea
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• v.25 no.2
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• pp.30-43
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• 2018

Background: Hemispatial neglect is defined as the failure to attend, report, respond, or orient toward meaningful stimuli provided in the contralateral side of a brain lesion. Objects: This study was conducted to find out the effect of dynamic trunk equilibirum exercise for stroke patients with hemi-spatial neglect. Methods: This study included 21 stroke subjects, randomly assigned to either the experimental group or the control group. The exercise program consisted of 5 sessions of 20 minutes per week during 4 weeks. The line-bisection test, the Albert test, the balance function score, the Berg balance scale, the postural assessment scale for stroke and the modified Barthel index were measured before and after training. All data were analyzed using SPSS 12.0 for Windows. Between-group and within-group comparison was analyzed by using Independent t-test and Paired t-test respectively. Results: The results of study were as follows: There were significant differences between before and after intervention in both group (p<.05). There were significant differences in the line-bisection test, Albert test, balance function score, Berg balance scale, postural assessment scale for stroke and modified Barthel index between the experimental group and the control group (p<.05). Conclusion: Dynamic trunk equilibrium exercise had a positive effect on patients' neglect, balance ability and activities of daily living. Further studies are required to generalize the results of this study.

• Korean Journal of Biological Psychiatry
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• v.13 no.3
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• pp.144-151
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• 2006

Objectives : Cognitive therapy is the most extensively researched psychological treatment for nonpsychotic unipolar outpatient depressive disorders. This review focused on the utility of this approach in severe or chronic depressive disorders, in relapse prevention and also on the potential benefits of combining cognitive therapy with medication. Methods : The author reviewed original studies and quantitative analyses on the effects of cognitive therapy, predictors of response, and neuroimaging studies of cognitive therapy in major depressive disorder. The sources used for the literature search were data bases : PubMed, EMBASE, CDSR on the internet, references in papers or books. Results : This review suggests that cognitive therapy is as effective as antidepressant medication in severe depressive disorders. And cognitive therapy can be an effective alternative to antidepressant medication. Patients benefited significantly more from combined cognitive therapy and antidepressant treatment than from either treatment alone. Most importantly, the addition of cognitive therapy to usual treatment appears to protect against future relapse in individuals known to be at high risk of repeated episodes of depression. In addition, subjects who received cognitive therapy showed significantly greater improvements in chronic depression than receiving antidepressant medication. Pooled data suggests that there is a significant relationship between the therapist's level of training or experience, the type of therapy used and patient outcome. Recent functional imaging studies examining brain changes following cognitive therapy report a variety of regional effects, but there is no consistent pattern across the few published studies. Conclusion : Cognitive therapy has proved beneficial in treating depressive patients. Despite empirical data supporting its efficacy, there are still problems in gaining access to cognitive therapy in clinical practice.

• Research in Community and Public Health Nursing
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• v.13 no.4
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• pp.795-807
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• 2002

Objectives: The purpose of this study was to develop a community-based nursing center model that can provide health promotion for infants and toddlers as well as a research and practice site for nursing faculty and students. Methods: Review of current health care system and health promotion programs, and workshops with brain-storming were carried out to identify needy areas of services to be provided by the nursing center. Finally, the community nursing center model was developed through expert consultation and filed visits. Results: The services and programs were developed for infants and toddlers residing in Seoul area. These services and programs include growth and developmental screening, environment and health problem assessment, infant stimulation and parent education, and self-help group. Full-time and part-time staff nurses and nurse practitioners will provide those services and offer home visiting if needed. Database system, health information system, and trainers' training programs were developed as well. Conclusion: The nursing center model developed in this study will ensure clients direct access to nursing care and increase of autonomy and accountability of nursing practices. The nursing center model focused on disease prevention and health promotion will enhance the quality of life of the infants, toddlers and their families as well as to decrease national health care expenditure.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.1
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• pp.46-50
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• 2015

The previous studies showed that the visual imagery activated the occipital and posterior inferior temporal area of the brain, and the damage to the occipital cortex impaired the visual mental imagery. We studied current-source distribution of electroencephalography (EEG) to observe neuronal activity during imagery tennis playing. Eleven healthy volunteers were enrolled. All volunteers were right-handed males and novices for tennis playing. The mean age of them was 24.9 years. The EEGs were recorded on the scalp electrodes located according to the International 10~20 System. The number of electrodes was 25 channels including subtemporal electrodes. The EEG recording session was 13 min including 5 segments: resting-I, scenery-slide show, resting-II, watching tennis-game video, and imagery-tennis playing. The recoding durations were 3, 2, 3, 2, and 3 min respectively. Five 'artifact free 3-sec segments' were selected in each segment of 'imagery-tennis playing' and 'resting-II'. We did the frequency domain analysis with the EEG segments using a distributed model of current-source analysis. The statistical-nonparametric maps (SnPMs) were obtained between the segments of 'imagery-tennis playing' and the segments of 'resting-II' (p<0.01). The significant change of current-source density was observed only in alpha-2 frequency band (10~12 Hz). The current-sourcedensity was increased in the hippocampus, parahippocampus, and occipital fusiform gyrus in the right cerebral hemisphere (p<0.01). Imaginary-tennis playing may activate the hippocampal-occipital alpha networks of nondominant hemisphere.