http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
마찰 저감을 위한 비극성 첨가제에 따른 acrylonitrile butadiene styrene계 플라스틱의 stick-slip 이음 저감 연구
여상준,정예원,최성욱,김효준,박건욱,손민영 한국음향학회 2024 韓國音響學會誌 Vol.43 No.1
최근 환경규제가 강화되고 고유가 문제로 인하여 전기차 시장이 점차 커지고 있으며 또한 내연기관 자동차에서도 엔진의 Noise, Vibration, Harshness(NVH) 관련 소음이 저감되고 외부에서 유입되는 소음의 차폐 기술이 발전됨에 따라 Buzz, Squeak, Rattle(BSR) 이음의 민감도가 증가하는 추세이다. 본 연구에서는 자동차의 Panoramic Curved Display(PCD)에서 발생하는 Stick-slip 이음과 고분자 플라스틱의 표면에너지 및 극성 성분과의 상관관계에 대하여 분석하였다. 극성 고분자 소재인 Acrylonitrile Butadiene Styrene(ABS)와 PolyCarbonate-Acrylonitrile Butadiene Styrene(PC-ABS)를 대상으로 컴파운드 소재를 제작하여 평가하였다. 결과적으로 고분자 플라스틱의 극성성분이 3.86 mN/m 이상일 때 Stick-slip 거동이 발생하였으며, 시간에 따른 마찰 거동에서 absolute transition slope가 증가할수록 Stick-slip의 이음 가능성이 증가하고 마찰계수의 값 차이가 클수록 Stick-slip 이음의 세기가 증가하였다.
여상준,박승원,김영백,황성남,최덕영,석종식,정동규,민병국,Yeo, Sang-Jun,Park, Seung-Won,Kim, Young-Baeg,Hwang, Sung-Nam,Choi, Duck-Young,Suk, Jong-Sik,Chung, Dong-Kue,Min, Byung-Kook 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.11
Objectives : Transpedicular screw fixation has become an important method for internal fixation in variety of disorders. However, acceleration of degeneration at the adjacent segment in any follow. The goal of this study is to review the change of motion ranges of vertebral joints adjacent to fused level in lumbar spine. Methods : This study consists of 22 patients with degenerative spinal instability. Treatment of spinal instability includes posterior fusion with transpedicular screw fixation or transpedicular screw fixation with posterior lumbar interbody fusion. The flexion-extension angle(FEA) was measured from dynamic views of lumbar spine taken both at preoperative and post operative period. Results : The FEA of upper vertebral joint adjacent(FEA-u) to a fused L4-5 level was increased(p=0.010). The FEA-u was increased in case of L5-S1 fusion(p=0.025). The change of FEA-u in case of L5-S1 fusion was greater than that in L4-5 fusion(p=0.013). Conclusion : After L4-5 fusion, there seems to be more meaningful increase in FEA of L3-4 than that of L5-S1. The reason may be due to the damage of L3-4 facet joints during the operation, the other possible explanation may be the anatomical stability of L5-S1 vertebral joint. The change of FEA-u of L5-S1 fusion is increased more than that of L4-5 fusion. Because there are compensations in the adjacent vertebrae both above and below the fused L4-5, the compensatory motion in FEA-u of L5-S1 fusion was greater than that of the L4-5 fusion.
케틀벨 스윙과 덤벨 스쿼트 동작 시 20대 남자 대학생의 둔부 근육 활성도 비교
여상준 ( Sang-jun Yeo ),박기덕 ( Gi Duck Park ) 한국발육발달학회 2016 한국발육발달학회지 Vol.24 No.3
The purpose of this study tried to identify what muscles show the most effective muscle activity through activity differences in each muscle and Kettlebell swing known to be efficient for strengthening the lower limb leg by measuring and comparing muscle activities of lower limb muscles, including hip muscles, while performing Kettlebell swing. A total of 24 healthy boy students were selected as subjects of this study, who had no pain nor surgical history of the knee or hip. Then, they were asked to perform Kettlebell swing, 3 sets of 5 times at 50% of 1RM. The results of this study showed that the average muscle activity and the maximum muscle activity of Biceps femoris, gluteus maximus, and gluteus medius made a statistically significant difference during Kettlebell swing (p<.001). These results are thought to be provided as basic materials for the development of programs for effectively strengthening low limb muscles.
케틀벨 스윙과 런지 동작 시 20대 남성 하지 근 활성도 비교
여상준(Yeo, Sang-Jun),윤성덕(Yoon, Seong-Deok),박기덕(Park, Gi-Duck) 한국체육과학회 2016 한국체육과학회지 Vol.25 No.5
The purpose of this study tried to identify what muscles show the most effective muscle activity through activity differences in each muscle and Kettlebell swing and Lunge known to be efficient for strengthening the lower limb leg by measuring and comparing muscle activities of lower limb muscles, including hip muscles, while performing Kettlebell swing and Lunge. A total of 24 healthy boy students were selected as subjects of this study, who had no pain nor surgical history of the knee or hip. Then, they were asked to perform Kettlebell swing and Lunge, 3 sets of 5 times at 50% of 1RM. The results of this study showed that the average muscle activity and the maximum muscle activity of Biceps femoris, gluteus maximus(p<.001), and gluteus medius made a statistically significant difference during Kettlebell swing (p<.001). These results are thought to be provided as basic materials for the development of programs for effectively strengthening low limb muscles.