• Journal of rehabilitation welfare engineering & assistive technology
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• v.9 no.2
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• pp.137-144
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• 2015

In this paper, we present an inertial sensor-based gait analysis system to measure and analyze lower-limb movements. We developed an integral AHRS(Attitude Heading Reference System) using a combination of rate gyroscope, accelerometer and magnetometer sensor signals. Several AHRS modules mounted on segments of the patient's body provide the quaternions representing the patient segments's orientation in space. And a method is also proposed for calculating three-dimensional inter-segment joint angle which is an important bio-mechanical measure for a variety of applications related to rehabilitation. To evaluate the performance of our AHRS module, the Vicon motion capture system, which offers millimeter resolution of 3D spatial displacements and orientations, is used as a reference. The evaluation resulted in a RMSE(Root Mean Square Error) of 1.08 and 1.72 degree in yaw and pitch angle. In order to evaluate the performance of our the gait analysis system, we compared the joint angle for the hip, knee and ankle with those provided by Vicon system. The result shows that our system will provide an in-depth insight into the effectiveness, appropriate level of care, and feedback of the rehabilitation process by performing real-time limb or gait analysis during the post-stroke recovery.

• Journal of Korea Entertainment Industry Association
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• v.13 no.7
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• pp.205-218
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• 2019

Music sampling, which has been popular since hip-hop DJs used it in the 1970s, is now one of methods of producing music that is used regardless of genre or country. In this study, an overall production methodology for music sampling was presented through in terms of content and techniques. First of all, in terms of the contents, we classified them into the reuse and length of materials, and the function of samples in the mixed songs. In terms of the techniques, editing and effecting techniques were classified. By combining these elements, the methodology of music sampling applicable to the productions as well as the analysis was presented. Based on this methodology, the sampled songs of Korean Popular musicians - Jang Ki-ha and Faces, Epik High, The Quiet, and DJ DOC - were successfully analysed. Through the analysis process, the organic relationship of elements within the methodology was investigated, and the results of the analysis showed the effectiveness of the proposed methodology. This study can be meaningful in laying the groundwork for applying music sampling directly when actually producing songs or analyzing sampled songs.

• Sleep Medicine and Psychophysiology
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• v.12 no.1
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• pp.39-44
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• 2005

Objectives: Much attention has been paid to sleep apnea syndrome (SAS) in the elderly because of its high prevalence. It is expected that SAS in the elderly has both similarities and differences compared to SAS in the young or middle-aged populations. The aim of this study was to elucidate the characteristics and consequences of SAS in the elderly. Methods: In this study we included 210 young or middle-aged adults between 23 and 59 years (20 women and 190 men) and 65 older adults between 60 and 83 years of age (16 women and 49 men). Respiratory disturbance indices (RDIs) of the study subjects were more than 5 in an overnight polysomnography. They completed the Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI). Informations about body mass index (BMI), neck, waist, and hip measurements, and blood pressure were obtained. Results: No difference was observed between older adults with SAS (older SAS) and adults aged under 60 with SAS (SAS aged under 60) in RDI, apnea index, % time of oxygen saturation less than 90%, and PSQI. Obstructive apnea index and oxygen desaturation index (ODI) were lower in older SAS. Compared to SAS aged under 60, lowest oxygen saturation and central apnea index were higher in older SAS, but they were statistically not significant. BMI and neck circumference were significantly lower in older SAS compared to SAS aged under 60. Diastolic blood pressure was lower in older SAS compared to SAS aged under 60 with no difference in systolic blood pressure. Older SAS showed lower scores in ESS than SAS aged under 60. Significant correlation was observed between RDI and BMI in SAS aged under 60, but not in the case of older SAS. The relationships between RDI and neck circumference, systolic and diastolic pressure, and ESS were similar. Conclusions: The elderly with SAS were not over-weight and there was no relationship between body weight and the severity of SAS. Also, the behavioral and cardiovascular effects of SAS were not marked in the elderly, which might be partly explained by decreased ODI and relatively higher lowest oxygen saturation in older SAS. The normal aging process, aside from increased body weight, might contribute to the development of SAS in the elderly with modest complications.

• Journal of dental hygiene science
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• v.9 no.4
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• pp.413-418
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• 2009

This study was to investigate the muscoulosckeletla pain from 214 dental hygienist during treatment process in Ulsan and Kyungnam. The data collection was done from March to May in 2009 with questionnaire. The study results were as follows. In the participant's age characteristic, under 23 years old(34.1%) was majority, other participant age group were 24~26 years old(33.6%), 25~29 years old(20.6%), and over 30 years old(11.7%). Other participant characteristic were unmarried participant(86.4%), none religion(43.5%), and graduation from college(88.3%). In the participant's business characteristic, working place were dental clinic(57.5%), and dental hospital(42.5%), career was 1~2 years(42.5%) and a number of change job was once(45.1%). Salary were 1,300,000~1,490,000 won (33.6%), 1,500,000~1,990,000 won(29.9%), under 1,300,000 won(26.2%), 2,000,000~2,490,000 won(7.5%). A number of dental hygienist was over 20 person(85.9%) and the average dental hygienist was 15.6 person. A number of dentist were one person(28.5%), 2 person(22.4%), 4 person(19.2%) and the average dentist was 3.2 person. Dental hygienist's working hour was 8~9(49.5%), a large part of dental hygienist was assistance of general treatment(70.1%). Other results were 5 days/week working(60.3%), and night shift(49.1%). In an effect of musculoskeletal pain during working, neck pain was significantly influenced by body posture such as "head forward 15 degree or head round", "non balanced shoulders", "bend waist", "bend wrist", and "sit astraddle on a chair". Shoulders pain was significantly influenced by body posture such as "head forward over 15 degree", "bend waist", and "stand up straightly". Knee pain was significantly influenced by body posture such as "stand up straightly", and hip pain was influenced by "sit astraddle on chair".