• Journal of Navigation and Port Research
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• v.31 no.8
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• pp.629-635
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• 2007

Reduced crew performance is frequently cited as a major causal factor in maritime accident causation. Although considerable research has been conducted on the hours of work undertaken by seafarers through interviews and the analysis of records, experimental studies to observe the effects of factors such as high workload, shift patterns, stress, sleep deprivation and disturbance on the cognitive performance of mariners have been limited. Other safety-critical transport industries, such as aviation and rail, have developed fatigue management tools to help manage the work patterns of their operators. Such a tool for mariners would assist shipboard crew, marine pilots and shore management in planning and improving work schedules. The overall aim of this paper is to determine a fatigue factor, which can be applied to human performance data, as part of a software program that calculates total cognitive performance. This program enables us to establish the levels of cognitive performance of a group of marine pilots to test a decision-making task based on radar information. This paper addresses one of the factors that may contribute to the determination of various fatigue factors: the effect of different work patterns on the cognitive performance of a marine pilot.

• Korean Journal of Cognitive Science
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• v.31 no.1
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• pp.1-23
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• 2020

This paper introduces SNUDM, an analysis program for Ratcliff's diffusion model, which has been one of the most important models in cognitive psychology over the past 35 years and which has come to occupy an important place in cognitive neuroscience in recent years. The analysis tool is designed with the basic principles of easy comprehension and simplicity in use. A diffusion process was programmed as the limit of a simple random walk in a manner resembling Ratcliff & Tuerlinckx(2002). The response time distribution of the model was constructed by simulating the time taken by a random walk until it reaches a threshold with small steps. The optimal parameter values in the model are found to be the smallest value of the chi-square values obtained by comparing the resulting distribution and the experimental data using Simplex method. For simplicity and ease of use, the input file used here is created as a file containing the quantile of the reaction time, the trials and other information. The number of participants and the number of conditions required for such work programs are given in a way that answers the question. Using this analysis tool, the experimental data of Ratcliff, Gomez, & McKoon(2004) were analyzed. We found the very similar pattern of parameter values to Ratcliff et al.(2004) found. When comparing DMAT, fast-dm and SNUDM with the generated data, we found that when the number of trials is small, SNUDM estimates the boundary parameter to a value similar to fast-dm and less than the DMAT. In addition, when the number of trials was large, it was confirmed that all three tools estimate parameters similarly.

• The Korean Journal of Rehabilitation Nursing
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• v.9 no.1
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• pp.15-24
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• 2006

Purpose: This study was to explore the cognitive function of Korean-Chinese stroke patient in China. Method: The study sample was 100 who were possible to communicate and agreed. The data were collected from one Brain's hospital at Yanji in China and by trained nurse from December 12, 2005 to April 28, 2006. The measurement tools were Digit span, Trail making, and MMSE-K. The data were analysed by SPSS Win 11.5 using frequency, t-test, ANOVA, and Pearson's correlation coefficients. Results: The mean score of DSF was 5.07, 3.42 of DSB, 161.37 of TMA, 229.28 of TMB, 22.64 of MMSE-K. There was a significant difference in DSF (F=6.35, p=.001), DSB (F=6.10, p=.001), TMA (F=3.53, p=.018), TMB (F=3.26, p=.025), MMSE-K score (F=12.97, p=.000) according to age, and DSF (F=6.67, p=.000), DSB (F=6.01, p=.000), TMA (F=5.82, p=.001), TMB (F=6.23, p=.001), and MMSE-K score (F=13.02, p=.000) according to educational level, and DSF (F=5.35, p=.006), DSB (F=3.16, p=.047), TMA (F=3.30, p=.041), TMB (F=3.42, p=.037), and MMSE-K score (F=4.95, p=.009) according to duration of disease, and DSB (F=3.54, p=.018), and MMSE-K (F=6.05, p=.001) according to frequencies of hospitalization. There was high correlation between DSF and DSB (r=.581, p=.000), TMA and TMB (r=.936, p=.000), MMSE-K and DSF (r=.579, p=.000), MMSE-K and DSB (r=.591, p=.000), DSF and TMA (r=.727, p=.000), and DSF and TMB (r=.721, p=.000). Conclusion: The cognitive evaluation score of Korean-Chinese stroke patients in China was in normal limit. The age, educational level, duration of disease and income were significant demographic characteristic affecting cognitive function. Further study need to compare the cognitive function of Korean-Chinese stoke patients in China and stoke patients in Korea.

• 재활복지
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• v.20 no.1
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• pp.189-210
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• 2016

The purpose of this study was to investigate the relationships between cognitive function and self efficacy, health behavior of the elderly participation to physical activity. Data were collected from November 2015 to January 2016. The study subjects were 61, aged 65 years or older, to visit health town. The questionnaire was composed general characteristics and K-MoCA, self-efficacy scale, self-efficacy for exercise tools, Korea's elderly health behavior. The results of the study were as follows: As for cognitive function and exercise self-efficacy by general characteristics, there were differences in that regard according to gender, education, marital status, dependents form, duration of the program(p <.05), the general self-efficacy showed differences in gender, age, education, economic status, duration of the program(p <.05), and the health behavior showed differences in gender, education, marital status, dependents form, activity program, duration of the program(p <.05). There was a significant correlation between cognitive function and exercise self-efficacy, health behavior(p <.01). General self-efficacy was correlated with exercise self-efficacy, health behavior. And exercise self-efficacy was correlated with health behavior(p <.01). Exercise self-efficacy were the factor affecting the cognitive function(p <.01). Therefore, the activity program development for the practice and sustainable participation in physical activity in the elderly is believed to be made.

• Journal of Society of Occupational Therapy for the Aged and Dementia
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• v.12 no.2
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• pp.97-106
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• 2018

Objective : The purpose of this study was to investigate the effects of reminiscence therapy using mind map to improve cognitive function, depression index, quality of life for old woman with dementia. Method : The study were 14 patients who were diagnosed with a woman suspected of dementia. They were randomly assigned to Study group(N=7) and control group(N=7). All patients received only to Study groups. reminiscence therapy using mind map was composed to 10 sessions, 40 minutes per sessions, 2 times a week, for 5 weeks. For result analysis, descriptive statistic, Wilcoxon signed rank test, and Mann-Whitney U test were used. The evaluation tools were Mini-Mental State Examination Korean Version (MMSE-K), Korean Version of Beck Depression Inventory (K-BDI), Korean Version of the World Health Organization Quality of Life Scale Abbreviated Version (WHOQOL-BREF). Result : There was a significant difference in cognitive function, depression index, and quality of life in the within group after intervention, and there was a significant difference in cognitive function in the between group comparison. Conclusion : According to the results of study, an easing effect was confirmed regarding reminiscence therapy using mind map for an old woman with dementia. using reminiscence therapy using mind map when applied to the improvement of cognitive function, depression index, quality of life.

• Therapeutic Science for Rehabilitation
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• v.8 no.1
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• pp.51-62
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• 2019

Objective: To develop and verify the usability of a cognitive rehabilitation system with diverse cognitive functional levels based on tangible objects for the elderly population. Methods: A study was conducted to investigate the system's strengths and weaknesses by upgrading it with responses from two groups of 15 patients and 4 occupational therapists. After undergoing three forms of training - regarding executive function, memory, and concentration for a total of 20-30 min, the participants were asked to answer a structured questionnaire about contents of the three forms of training, hardware including the tablet PC functioning as a CPU and display media and tangible objects, and satisfaction of experiential usage of the system. Results: Both groups responded that the most interesting training area was executive function while the least interesting was concentration. Six participants reported that the size of the screen of the tablet PC was inappropriate, and five responded that the size of the tool was inappropriate. All therapists and 40% of the patients responded that they were satisfied with this system. Conclusion: This system's features include easy manipulation of tangible tools for performing training tasks, easy selection of and training in cognitive areas based on users' needs, and automatic adjustment of difficulty level based on users' performance. The training environment was designed to be similar to the natural environment by using tangible objects in both hands as input devices for the system, and the system was considered as an alternative to the lack of community cognitive rehabilitation specialists.

• Korean Journal of Cognitive Science
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• v.33 no.3
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• pp.155-168
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• 2022

In this paper, we introduce the SNUDM-G, a diffusion model analysis tool with improved computational speed. Although the diffusion model has been applied to explain various cognitive tasks, its use was limited due to computational difficulties. In particular, SNUDM(Koh et al., 2020), one of the diffusion model analysis tools, has a disadvantage in terms of processing speed because it sequentially generates 20,000 data when approximating the diffusion process. To overcome this limitation, we propose to use graphic processing units(GPU) in the process of approximating the diffusion process with a random walk process. Since 20,000 data can be generated in parallel using the graphic processing units, the estimation speed can be increased compared to generating data through sequential processing. As a result of analyzing the data of Experiment 1 by Ratcliff et al. (2004) and recovering the parameters with SNUDM-G using GPU and SNUDM using CPU, SNUDM-G estimated slightly higher values for certain parameters than SNUDM. However, in term of computational speed, SNUDM-G estimated the parameters much faster than SNUDM. This result shows that a more efficient diffusion model analysis for various cognitive tasks is possible using this tool and further suggests that the processing speed of various cognitive models can be improved by using graphic processing units in the future.

• Journal of Oriental Neuropsychiatry
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• v.34 no.3
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• pp.141-150
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• 2023

Objectives: This study aimed to comprehend the characteristics of Korean medicine patterns in relation to varying degrees of cognitive impairment in an elderly population. Methods: The dataset included 127 elderly individuals with cognitive impairment obtained from three Korean medicine hospitals between 2018 and 2021. The participants were categorized into two groups based on Clinical Dementia Rating-Sum of Boxes (CDR-SB) scores: those with questionable impairment (QI) and those with very mild dementia (VMD). A diagnostic framework for Korean medicine patterns encompassing Qi deficiency, Yin deficiency, Phlegm dampness, and Heat-fire was employed. Liver blood markers, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and the AST/ALT ratio, were also analyzed. Results: The scores of the cognitive assessment tools (MoCA-K, MMSE-DS, and K-IADL) of the QI group significantly differed from those of the VMD group. CDR-SB exhibited a positive correlation with the scores of each pattern of Qi deficiency, Yin deficiency, Phlegm dampness, and Heat-fire, whereas ALT and AST values displayed negative correlations. Binomial logistic analysis, controlling for potential confounders, such as age, education years, body mass index, the presence of chronic disease, and the presence of medication, verified that the VMD group showed higher pattern scores and lower ALT and AST values than the QI group. Conclusions: Increases in pattern scores along with decreased AST and ALT levels might be indicative of more severe cognitive impairment.

• Communications of Mathematical Education
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• v.33 no.4
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• pp.471-488
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• 2019

This paper aims to examine how mathematical history is used in $ textbooks according to the 2015-Revised Curriculum. We analyze the distribution and characteristics of making use of the mathematical history in the nine textbooks, using the framework suggested by Jankvist (2009) on the whys and hows of using historical tasks. First, the tasks related to mathematical history in the textbooks are mostly used as an affective tool, while few tasks are used as a cognitive tool. Second, most of the historical tasks of the type of an affective tool are introducing the anecdotes of mathematicians or in the history of mathematics, and only one case is trying to show human nature of mathematics by illuminating the difficulties mathematicians were faced with. Third, all the mathematical history tasks used as affective tools and goals are illumination materials, while only two out of the ten tasks in the category of a cognitive tool are illumination materials, yet eight others are modular ones. Considering the importance and value of using mathematical history in the math education, this paper recommends that more modular materials on mathematical history tasks in the category of cognitive tools and goals should be developed and their deployment in the textbooks or courses should be promoted. $

• Journal of The Korean Association For Science Education
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• v.37 no.5
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• pp.891-909
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• 2017

This study analyzed some of the discrepancies in quantitative and qualitative data focusing on cognitive and affective achievement in science education. Academic and affective achievement score of 308 high school students were collected as quantitative data, and 33 students were interviewed for qualitative data. We examined the causes and types of discrepancies in terms of testing tools. As a result from quantitative data, there were a large number of students with a big difference between subjects in cognitive achievement, and constructs in affective achievement. More than 20% of the students did not match tendency between achievements in two areas. Through interviews, some examples such as intentional control of science learning for future study and careers, different responses by differences in perception between school science and science, appeared. A comparison of quantitative data by testing tool between qualitative ones and interviews showed conflicting result, where most students evaluated themselves differently from their own quantitative data. That is due to the students' interaction with the testing tools. Two types of discrepancy related to testing tool are found. One is 'the concept difference between the item developer and students,' the other is 'the difference between students' exposed response and their real mindset.' These are related to the ambiguity of the terms used in the tool and response bias due to various causes. Based on this study, an effort is required to elaborate the testing item that matches students' actual perception and to apply students' science learning experience to testing items.