• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.1
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• pp.36-41
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• 2013

In this paper time series wave data are simulated using wave spectrum with random phases of the wave signal. The simulated wave signals are used to study the effect of the sampling rate on the ocean wave characteristics. Effect of sampling rate on wave data which include extreme wave such as freak waves are examined and various wave characteristics including abnormality index (AI), kurtosis of wave profile and maximum wave height are examined. Various wave heights are decreased as the sampling rate decreases. The zero-th moment of the wave spectrum does not affect much on the sampling rate but the second moment are greately affected on the sampling rate. The error due to the sampling rate is decreases as the wave period increases. The error in significant wave height based on the wave spectrum $H_s$ is smaller than that on the time domain method $H_{1/3}$. AI index and kurtosis of wave profile do not deviate much from the exact date as long as the sampling rate is greater than 1 Hz. Ocean wave measurement with the sampling frequency higher than 1 Hz will result the error less than 5% in estimating the height of extreme waves.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.3
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• pp.285-294
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• 2020

This study investigated the use of Ground Penetrating Radar (GPR) over a two-decade period on public roads, focusing on the electromagnetic characteristics of the pavement dielectrics and attenuation. From the results, a typical range of characteristic value, influencing factors, and a correction method were suggested. The typical dielectrics of asphalt pavements were 4-7, as measured by an air-coupled 1 GHz GPR antenna. The dielectrics of concrete pavements were very large in the early age, but were drastically reduced with ageing. Ten years on, collection was in the range of 6-12. The dielectrics were proportional to the relative humidity (R.H.) of the atmosphere. The effects were reduced to one eighth with an overlay. Attenuation generally increased with thickness of the road layer, and also increased where there was damage. The GPR results could also vary depending on the weather conditions as well as on the characteristics of the GPR equipment, even at the same frequency. Therefore, GPR surveys should be performed on road surfaces without debris on a single, fine day. The reliability of the GPR analysis could be improved by cores and equipment calibration with other non-destructive test surveys.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.654-659
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• 2018

In this study, continuous long-term observation is implemented with an ocean radar. Ocean radar conducts remote observation (combined) with ground-based radars, which enable a series of simultaneous observations of an extensive range of the coast with high frequency. An ocean radar for continuous long-term observation is operated at Samcheok on the east coast of Korea. Samcheok experienced tsunami damage in recent years and is the location of a nuclear power plant. In order to examine the reliability of the ocean radar, a pressure-type wave gauge, ultrasonic wave gauge, and ocean buoy are installed for the purpose of data comparison and verification. The ocean radar used in this study is an array-type HF-RADAR named WERA (WavE RAdar). The analysis of the data obtained from continuous long-term observations showed that the radar observations were in agreement with more than 90% of the wave data collected within a 25 km range from the center of two sites. Less than 1% of the entire observation data was unmeasured by the time series analysis. As a result of comparing the radar data with the direct observations made by the wave gauge, it was inferred that the RMS deviation is less than 20cm and the correlation coefficient was in the range of 0.84 ~ 0.87. Moreover, supported by such observations, a comprehensive monitoring system is being developed to provide the public with real-time reports on waves and currents via the internet.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.261-268
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• 2015

This study is aimed at clarifying the influence of an elementary school student's leadership on the Entrepreneurial spirit, and whether the career awareness really gives a regulatory effect on the Entrepreneurial spirit. This study organized the students above 4th grade in an elementary school located in Seoul as research subject; then this study analyzed the collected 420 questionnaires in August, 2015, using SPSS 21.0 Statistical Program. This study used frequency analysis, descriptive statistic analysis and cross analysis as a statistic analysis method. The research issues include 1)Does the leadership of an elementary school student have a significant influence on the Entrepreneurial spirit? 2) Is it possible for career awareness to play a regulatory role in the relationship between an elementary school student's leadership and the Entrepreneurial spirit? The research results of this study are as follows: First, it was found that an elementary school student's leadership has a significant influence on the Entrepreneurial spirit. Second, about whether independent variable factors cause a difference in career awareness as regulating variable in the relationship, in which independent variable factors have an influence on the Entrepreneurial spirit, only a part shows a significant effect as a regulating variable. This study hopes that this research results could provide data to meet the educational alternative to the necessity of leadership education required by the present period, and provide the basis of the use for educational policy for elementary school students with this research results as the center.

• Progress in Medical Physics
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• v.18 no.2
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• pp.73-80
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• 2007

Fruitful findings have been produced from five out of sixty cells which were obtained from each 63 individual Aplisia caught at the Jeju coast. Spiking patterns of three out of five cells, such as relaxation oscillator, bursting within a short time of the inter-burst interval, chaotic bursting, period doubling sequences, bursting with long trains of action potentials separated by short silent periods, regular repeated beating or elliptic bursting, and silent states had been changed in order as the temperature was lowered to $10^{\circ}C\;from\;32^{\circ}C$. In the intervals of every about 40 minutes repeated ups and downs of temperature produced similar firing patterns at the allowable temperature ranges. The other two cells showed difference from these. The amplitudes of the action potentials of the two cells will not be highly decreased in 24 hours. Average spike frequencies, the inter-burst interval, peak to peak spike amplitude of action potentials, minimum potential values are compared and analyzed by using the computer programme. The spike frequencies according to temperature show the distribution of bell type, with maximal spike frequencies at intermediate temperatures and minimal ones at either end. The most common pattern consist of high spike frequency during failing and low one during rising temperatures.

• Journal of IKEEE
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• v.24 no.3
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• pp.754-765
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• 2020

Currently, Intelligent femoral prostheses that support the corresponding mode in walking and specific movements are being studied. Certain controls such as upstairs, sitting, and standing require a technique to classify control commands based on the user's intention because the mode must be changed before the operation. Therefore, in this paper, we propose a technique that can classify various control commands based on the user's intention in the intelligent thigh prosthesis system. If it is determined that the EMG signal needs to be compensated, the proposed technique compensates the EMG signal using the correlation between the strength and frequency components of the normal EMG signal and the muscle volume estimated by the pressure sensor. Through the experiment, it was confirmed that the user's intention was accurately detected even in the situation where muscle fatigue was accumulated. Improved intention detection techniques allow five control modes to be distinguished based on the number of muscle contractions within a given period of time. The results of the experiment confirmed that 97.5% accuracy was achieved through muscle tone compensation even if the strength of the muscle signal was different from normal due to muscle fatigue after exercise.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.375-385
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• 2008

This research was conducted with the aim of providing basic data to a non profit organization's strategies by determining the influence of the service quality cognition of the aged people's excercise program on service satisfaction. The subject of this study was sixteen districts in city B, and aged people who participates in the district's exercise programs. 320 subjects were selected based on a purposeful sampling, and the survey sheets of 308 subjects, excluding 12 of those who lacked sincerity were used for th analysis. To prove the hypothesis of the study based on the sampled data, t-test, One-way ANOVA and regression analysis were conducted using the SPSS Ver. 12.0 statistics program, and the results are as follows: First, perceived service quality differed, but service satisfaction did not differed on the gender. Second, perceived service quality partially differed, but service satisfaction did not differed on the age. Third, perceived service quality partially differed, but service satisfaction did not differed on the frequency. Fourth, perceived service quality and service satisfaction partially differed depending on the period. Fifth, performance, out of the perceived service quality factor, was found to had positive influence on service satisfaction.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.316-322
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• 2019

The purpose of this study is to investigate the opinions of non-health science college students of Korean dental hygienists in the category of medical personnel. A self-reported questionnaire was conducted on 265 non-health science major students without information about a health and medical service personnel. The collected data were analyzed using frequency, percentage, descriptive statistics, chi squared and multinomial logistic regression analysis. About 40% of the respondents answered that dental hygienists should be medical personnel, while 17.7% think that they should not distinguish health and medical service personnel between medical personnel and medical service technologist. As the respondents' oral health management ability improved, they approves the Korean dental hygienists in the category of medical personnel(p=.022). As the longer the period of dental regular visits, they answered that dental hygienists should be medical service technologist. Presence or absence of dental regular visits, scaling experience, oral health education did not no significant difference on the opinions of Korean dental hygienists in the category of medical personnel of the pros and cons. This study can be used as a basic data for establishing the policy of medical personnel for dental hygienists.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.313-322
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• 2019

This study poses a question on whether the Jangmadang Generation, which has been the focus of the sociological interest, can form an actual generation by transcending the social classes, status of students, ethnicity, and gender, etc. Therefore, in this study, the author compared the consciousness of the Jangmadang Generation in terms of politics, education, society, compliance with law, and education with their preceding generations. The data used in this study were gathered from the North Korean defectors who defected within the past five years over the period from November to December 2016. A total of 200 questionnaires were used for data analysis, which was conducted using SPSS 20.0, in order to show differences between groups and perform frequency analysis. The analysis results showed that the consciousness of the Jangmadang Generation in politics, society, compliance, and education was lower, while the economic consciousness was significantly higher compared to earlier generations. As their objective generational status, the Jangmadang Generation had experienced the 'March of Ordeal' and 'Collapse of Public Education' while they were still teenagers. Such a difference in their generational status influenced the formation of different consciousness as a generation compared to the earlier generations. Compared to the earlier generations who received 'proper public education,' the Jangmadang Generation, who did not receive 'decent public education' shows a generally lower level of consciousness compared to the earlier generations. As such, the Jangmadang Generation has the potential to form a separate generation with a different generation consciousness from that of earlier generations.

• The Journal of Korean Academy of Sensory Integration
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• v.16 no.3
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• pp.23-33
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• 2018

Objective : The purpose of this study is to investigate trend in use of occupational therapy assessment tools used by pediatric occupational therapist. Methods : Survey questionnaire developed for this study were used to for data collection. The questionnaires are divided into 10 area: occupational performance, activities of daily living, education, play, sensory-perceptual, motor and praxis, cognition, social interaction skills, development, and physical examination. Total 105 responses were analyzed using descriptive statistics analysis and frequency analysis. Results : For the general process of evaluation in pediatric occupational therapy, major response on the initial evaluation time was 30~60minutes (41.9%), and major response on the re-evaluation period was 3~6months (41.0%). The major assessment tool for each area Canadian Occupation Performance Measure (55.2%) for occupational performance assessments, Wee Functional Independence Measure (57.1%) for activities of daily living assessments, School Function Assessment (2.5%) for education assessments, Knox Preschool Play Scale (28.6%) for play assessments, Developmental Test of Visual Perception (94.3%) for sensory-perceptual assessments, Bruininks-Oseretsky Test of Motor Proficiency (42.9%) for motor and praxis assessments, Evaluation of Social Interaction (6.1%) for social interaction skills assessments, Denver Developmental Screening Test (92.4%) for development assessments, Clinical Observation (89.5%) for physical examination assessments. Conclusion : The study identified the most assessment tools used for specific area by pediatric occupational therapists. The results can be used as a basic data to educate about pediatric occupational therapy evaluation, as well as to develop new assessment tools in pediatric setting in future.