회사정리법상의 실권(失權)과 민소법 제201조 제2항의 원상회복의무와의 관계(1)

채원식 한국사법행정학회 1982 사법행정 Vol.23 No.6

전기근육자극 시 주파수 차이가 대퇴 근육 기능에 미치는 영향

채원식,정재후 한국운동역학회 2023 한국운동역학회지 Vol.33 No.1

Objective: The purpose of this study was to investigate the effects of different frequency on of knee extensors muscle function during electrical muscle stimulation (EMS). Method: In this research, 40 subjects who have no musculoskeletal disorder, and less than a year workout experience were recruited in order to analyze effects of EMS with different stimulus frequency. Forty subjects were randomly divided into four groups of ten subjects in each group. A EMS training program with different frequencies (without EMS [WE], EMS with frequency 30 Hz [E30], EMS with frequency 60 Hz [E60], EMS with frequency 90 Hz [E90]) was assigned to each group. Throughout eight weeks of training, test subjects were simultaneously carried out knee extension exercises such as squat, leg extension, and leg-press while using EMS with different frequency (20 min, pulse width 250 μs, on-off ratio 1:1). Isokinetic knee extension strength, muscle activity of the rectus femoris (RF), the vastus medialis (VM), and the vastus lateralis (VL), and the median frequency of the RF, the VM, and the VL were collected and compared between pre and post training in order to find effects of applying EMS with different frequencies. For each dependent variable, a one-way ANOVA was to determine whether there were significant differences among four different conditions (p<.05). When a significant difference was found, post hoc analyses were performed using the contrast procedure. Results: When compared to WE and E90, E30 causes significant increase in isokinetic knee extension strength. No significant differences were found in EMG values across different EMS conditions. However, the median frequency of the VM in E30 was significantly increased than the corresponding value for WE. Conclusion: The results of this study showed that EMS training with 30 Hz frequency had positive effect on knee extensor. Based of the findings of the present study, EMS training with lower frequency may help the performer to focus on developing strength in knee extensor muscles.

FES 치료 시 자극 주파수 차이가 퇴행성 슬관절염 환자의 대퇴근 기능에 미치는 영향

채원식,정재후 한국운동역학회 2022 한국운동역학회지 Vol.32 No.4

Objective: The purpose of this study was to investigate the effects of different frequency on muscle function of the thigh in patients with degenerative knee arthritis during the functional electrical stimulation (FES). Method: For this study, 16 male participants over 65 who patients with degenerative knee arthritis were recruited as research participants. In this research, isokinetic muscular function, EMG, and joint position sensation were performed after FES treatment was applied for three conditions (FES 20, FES 50, and Without FES). For each dependent variable, one-way ANOVA with repeated measures was to determine whether there were significant differences among three different conditions (p<.05). When a significant difference was found, post hoc analyses were performed by using the contrast procedure. Results: When compared to FES 50 and without FES, FES 20 causes significant increase in isometric knee extension strength. No significant differences were found in EMG values across different EMS conditions. Conclusion: The present study examined isokinetic muscular function, EMG, and joint position sensation in order to investigate the effects of different frequency muscle function of knee extensors during the functional electrical stimulation. The results of this study showed that FES with 20 Hz frequency had positive effect on knee extensor. Based on the findings of the present study, FES with lower frequency may help the performer to focus on developing strength in knee extensor muscles.

The Effect of Exercise Intensity on Muscle Activity and Kinematic Variables of the Lower Extremity during Squat

채원식,정재후 한국운동역학회 2017 한국운동역학회지 Vol.27 No.3

Objective: The purpose of this study was to determine how exercise intensity affects muscle activity and kinematic variables during squat. Method: Fifteen trainers with >5 years of experience were recruited. For the electromyography (EMG) measurements, four surface electrodes were attached to both sides of the lower extremity to monitor the rectus femoris (RF) and biceps femoris. Three digital camcorders were used to obtain three-dimensional kinematics of the body. Each subject performed a squat in different conditions (40% one-repetition maximum [40%1RM], 60%1RM, and 80%1RM). For each trial being analyzed, three critical instants and two phases were identified from the video recording. For each dependent variable, one-way analysis of variance with repeated measures was used to determine whether there were significant differences among the three different conditions (p<.05). When a significant difference was found, post hoc analyses were performed using the contrast procedure. Results: The results showed that the average integrated EMG values of the RF were significantly greater in 80%1RM than in 40%1RM during the extension phase. The temporal parameter was significantly longer in 80%1RM than in 40%1RM and 60%1RM during the extension phase. The joint angle of the knee was significantly greater in 80%1RM than in 40%1RM at flexion. The range of motion of the knee was significantly less in 80%1RM than in 40%1RM and 60%1RM during the flexion phase and the extension phase. The angular velocity was significantly less in 80%1RM than in 40%1RM and 60%1RM during the extension phase. Conclusion: Generally, the increase of muscle strength decreases the pace of motion based on the relation between the strength and speed of muscle. In this study, we also found that the increase of exercise intensity may contribute to the increase of the muscle activity of the RF and the running time in the extension phase during squat motion. We observed that increased exercise intensity may hinder the regulation of the range of motion and joint angle. It is suitable to perform consistent movements while controlling the proper range of motion to maximize the benefit of resistance training.

회사정리계획의 인가후(認可後)의 변경(하)

채원식 한국사법행정학회 1986 사법행정 Vol.27 No.6

도시의 사회병리 도시와 범죄

채원식 대한지방행정공제회 1967 도시문제 Vol.2 No.10

N/A

인(人) 물(物) 돈 시간

채원식 한국사법행정학회 1977 사법행정 Vol.18 No.12

Molecular Sensing Efficiency of Gold-Silver Alloy Nanowires

채원식,Hee-Ok Lee,Eun-Mee Kim,Hyunung Yu 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.4

no abstract

Fabrication of 50 to 1000 nm Monodisperse ZnS Colloids

채원식,Ryan J. Kershner,Paul V. Braun 대한화학회 2009 Bulletin of the Korean Chemical Society Vol.30 No.1

Monodisperse ZnS colloidal particles with precisely specified diameters over a broad size range were synthesized by controlled aggregation. Sub-10nm ZnS seed crystals were first nucleated at ambient temperature and then grown at an elevated temperature, which produced large polydisperse colloidal particles. Subsequent rapid thermal quenching and heating processes induced a number of secondary nucleations in addition to growing the large polydisperse microparticles which were finally removed by centrifugation and discarded at the completion of the reaction. The secondary nuclei were then aggregated further at elevated temperatures, resulting in colloidal particles which exhibited a nearly monodisperse size distribution. Particle diameters were controlled over a wide size range from 50 nm to 1 μm. Mie simulations of the experiment extinction spectra determined that the volume fraction of the ZnS is 0.66 in an aggregated colloidal particle and the colloidal particle effective refractive index is approximately 2.0 at 590 nm in water. The surface of the colloidal particles was subsequently coated with silica to produce ZnS@silica core-shell particles.

롤러 신발과 조깅 슈즈 신발 착용 후 보행 시 지면반력의 형태 비교 분석

채원식 한국운동역학회 2006 한국운동역학회지 Vol.16 No.1