뒤넙다리근 강화 운동 시 넙다리네갈래근과 뒤넙다리근의 동시 수축에 대한 근전도 분석

황영인,문상재,박두진 대한고유수용성신경근촉진법학회 2019 PNF and Movement Vol.17 No.3

Purpose: This study identified the co-activation of quadriceps and hamstring muscles during hamstring strengthening exercises in healthy adults. Methods: Twenty-one participants were required for the present study design to achieve 80% power, 0.8 effect size (η2), and an alpha level of 0.05. Thus, this study recruited 21 healthy adults. All participants performed Nordic exercises, bridge exercises, and one-leg deadlifts randomly. The activity of the rectus femoris, vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), and semitendinosus (SM) were measured. In addition, the ratios of VM/VL and hamstring/quadriceps (HQ) were measured during the three hamstring strengthening exercises using electromyography. One-way ANOVA was used to compare the co-activation of quadriceps and hamstring muscles in the three exercises. Results: The activity of VM and VL during the performance of one-leg deadlifts was significantly higher than the other two exercises. The BF had significantly higher activity during the Nordic exercises compared to the other two exercises. In addition, the SM activation was significantly greater during Nordic exercises than one-leg deadlifts. Additionally, there was significant difference in HQ ratio among hamstring strengthening exercises. In specific, the one-leg deadlifts yielded a significantly lower HQ ratio. Conclusion: This study revealed that one-leg deadlifts are effective in rehabilitation for anterior cruciate ligament injury. In addition, Nordic exercises can be recommended to facilitate hamstring muscle activation.

Performance Comparison of Ultrasonic Focusing Techniques for Phased Array Ultrasonic Inspection of Dissimilar Metal Welds

황영인,박진현,김학준,송성진,조용상,강성식 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.4

Dissimilar metal welding that is the joining of two different metals which would not be welded together has been used in nuclear power plants so that the probability of occurrence of cracks that can cause serious accidents is high. Therefore, it is necessary to diagnose and investigate structures with dissimilar metal welds through nondestructive testing techniques. Among them, nondestructive evaluation techniques using phased array ultrasonic waves have been widely used and studied. However, transmitted ultrasound into dissimilar metal welds is split, skewed and distorted due to course grained anisotropy and inhomogeneity. Therefore, there are many limitations in tests using the conventional phased array ultrasonic technique. In this study, the phased array ultrasonic focusing methods such as phase matching method, adaptive focusing method and time reversal method were applied to the nondestructive ultrasonic testing of dissimilar metal welds for detecting internal cracks, and the performance and efficiency of each technique were compared through numerical simulations and experiments.

위성영상을 이용한 산불피해 이후 자연복원과 인공복원 방법에 따른 식생회복 모니터링

황영인,강원석,박기형,이경철,한상균,권형근,Hwang, Yeong In,Kang, Won Seok,Park, Ki Hyung,Lee, Kyeong Cheol,Han, Sang Gyun,Kweon, Hyeong Keun 국립한국농수산대학교 교육개발센터 2022 현장농업연구지 = Journal of practical agricultural resear Vol.24 No.3

This study was conducted to monitor the vegetation recovery in the areas damaged by the forest fires on the east coast that occurred in April 2000. The study site was a forest fire-damaged area in Samcheok-si, Gangwon-do, and 21 monitoring areas (12 natural restoration sites, 9 artificial restoration sites) were selected to analyze the vegetation recovery trend since 1998. The vegetation recovery trend was compared by calculating the values according to the year using the difference Normalized Burn Ratio (dNBR) and Normalized Difference Vegetation Index (NDVI) based on satellite images (Landsat TM/ETM+ and Sentinel-2A). As the result of this study, all 21 sites, vegetation was recovered, and both groups showed the greatest recovery in summer. In the case of the dNBR, the artificial restored sites showed higher values than the natural restored sites, and in the case of the NDVI, the natural restored sites were higher than the artificially restored sites in summer and autumn. However, the difference between the two groups of natural and artificial restoration sites was not significant. Therefore, the direction of forest restoration after forest fire damage can be effectively restored if properly implemented for the purpose of restoration of the target site.

AFO형 탄력밴등가 슬관절 통증 환자의 보행 패턴에 미치는 영향

황영인 호서대학교 기초과학연구소 2020 기초과학연구 논문집 Vol.28 No.1

2-Year Follow up of Balance in Stroke Patients after Myofascial Release using a Tennis Ball -Four Case Reports-

황영인,윤장원,박두진 대한고유수용성신경근촉진법학회 2018 PNF and Movement Vol.16 No.1

Purpose: Myofascial release (MFR) is an effective treatment for improving muscle stiffness and balance in neurological patients. This study examined long-term effects of MFR on the balance ability of stroke patients. Methods: MFR using a tennis ball was applied to the lower extremity and sacroiliac joint of the affected side of four stroke patients. The four subjects performed the Berg balance scale (BBS) and Timed up and go (TUG) test at the beginning of an 8-week intervention, directly after the intervention, and 2 years later. Results: The BBS scores indicated a trend toward maintenance of balance (p=0.05), but there was no difference in the TUG time (p=0.47). Conclusion: MFR may be a clinically meaningful intervention to maintain balance in stroke patients over a long period. However, the sample size in this study was too small to draw general conclusions. A larger study with more participants is needed.

물리치료 전공연계 봉사활동이 지역사회 노인 건강 증진에 미치는 효과

황영인 호서대학교 기초과학연구소 2019 기초과학연구 논문집 Vol.27 No.1

현재 우리나라는 고령화로 인해 노인의 건강과 관련된 문제에 직면에 있다. 이러한 문제를 해결하기 위해 다양한 방면의 접근이 필요하며 특히 노인의 신체적, 정신적 건강의 측면과 관련된 문제가 많이 대두되고 있다. 또한 이러한 문제를 해결하기 위한 비용적인 측면도 간과할 수 없는 부분이다. 본 연구는 이러한 여러 가지 문제점을 해결할 수 있는 방안의 하나로 물리치료 전공연계 봉사활동 추진을 제안하고자 한다. 본 연구에서는 호서대학교 물리치료학과 물리치료 전공연계 봉사활동을 실시한 후 노인의 건강 증진에 있어 긍정적인 영향을 미친 것으로 조사되었다. 개선되는 분야는 주로 통증의 감소, 능동관절가동범위의 증가, 근력증가, 균형 및 호흡의 증가로 나타났다. 향후 지역사회 노인 건강 증진 효과와 전공연계 봉사활동 시스템을 확장시켜 여러 가지 문제를 해결할 수 있을 것이라 사려 된다.

Comparison of the effects of different-sized airways in inspiratory trainers on maximal inspiratory pressure and rating of perceived exertion scale in healthy young people

황영인,Ki-Song Kim 물리치료재활과학회 2018 Physical therapy rehabilitation science Vol.7 No.1

Objective: This study aimed to investigate the effect of different-sized airways of the inspiratory muscle trainer (IMT) on maximal inspiratory pressure (MIP) and the rating of perceived exertion, as measured by the modified Borg scale (m-Borg). Design: Cross-sectional study. Methods: Twenty healthy subjects (10 men, 10 women) volunteered for the study. The spirometry was used to measure MIP. The trial order of the three spirometry conditions was chosen randomly. After measuring the MIP and before taking the final break, each of the conditions were immediately measured using the m-Borg. All subjects used the IMT with an airway diameter of 5-, 6-, and 7-mm. Results: The MIP significantly decreased with the decreasing airway diameter of the IMT (p<0.001), and the differences in all three conditions (7- and 6-mm, 6- and 5-mm, and 7- and 5-mm airways) were significant (p<0.05). The RPE significantly increased with the decreasing airway diameter of the IMT (p<0.001), and the differences in all three conditions (7- and 6-mm, 6- and 5-mm, and 7- and 5-mm airways) were significant (p<0.05). Conclusions: Decreasing the airway diameter of the IMT decreased the MIP and increased the m-Borg. In regards to physical exercise within the clinical setting, the m-Borg could be a useful as a prior monitoring method to prevent dyspnea for patients with narrowed airways (blocked with secretion or sputum in pulmonary disease) and the different-sized airways of the IMT could be applied as a useful tool to improve MIP for prevention of pulmonary disease.

인체 조직에 적용을 위한 고강도 집속 초음파 기술의 연구

황영인,김학준,송성진,배재현,김기복,강성식,유성원 한국물리학회 2017 새물리 Vol.67 No.4

High-intensity focused ultrasound (HIFU) has been used in clinics as a non-invasive treatment for diseased tissue through ablation by focusing the ultrasonic energy to a target tissue in the human body. Thus, HIFU can be non-invasively applied to treat patients with some cancers. If the HIFU energy is to be focused to a target in the complex human body, a precise ray-tracing method/technique is necessary. Therefore, ultrasonic simulations for HIFU by calculating the HIFU beam fields in a biological multi-layered model through irregular surfaces can support the design and the operation of a HIFU system. In this study, the simulations were performed according to the parameters of the HIFU sensor and were applied to a humanized tissue structure for describing the result at focal point and measuring the pressure and the temperature rises around target. The possibility of predicting the path of the ultrasonic wave penetrating into unspecified human tissue was ascertained and the ultrasonic focusing efficiences were compared according to the design variables. In addition, the in-vivo temperature could be determined by calculating the heat energy as a function of the sound intensity. 고강도 집속 초음파 (HIFU)는 집속 초음파 에너지를 이용하여 표적조직의 병변을 절제하는 비침습적인 치료법이며, 이 기법의 주된 장점은 절개없이 조직 절제가 가능하다는 점이다. 이에 따라, HIFU는 전립선, 유방, 간, 신장 및 자궁 내의 종양을 치료하기 위해 비침습적으로 적용이 가능하다. HIFU 에너지를 복잡한 인체 구조 내 종양과 같은 조직에 집속시키기 위해서 정확한 파선추적 기법 및 기술이 필수적이다. 그러므로, 불규칙적인 표면을 통한 다층구조 인체 모델에 투과한 HIFU 시뮬레이션은 HIFU 치료 시스템을 설계하고 구축하는데 도움이 된다. 본 논문에서는, HIFU 센서의 설계인자에 따른 시뮬레이션이 수행되었으며 집속 지점에서의 시뮬레이션 결과를 묘사하고 압력 및 온도 상승을 측정하기 위하여 인체 유사 구조에 적용해보았다. 이를 통하여 불특정한 인체 조직에서의 초음파 파선에 대한 경로를 예상할 수 있었으며, 각각의 설계변수에 따른 초음파 집속 효율을 비교할 수 있었다. 또한 음향강도에 따른 열에너지 계산에 따라 생체 내 온도를 계산할 수 있었다.

Improving the ultrasonic imaging of hydrogen-induced cracking using focused ultrasound

황영인,김학준,송성진,임종수,유성원 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.8

Hydrogen-induced cracking (HIC) is one of the main factors in collapses and breakages of structural steel in gas and oil industries. As one of the nondestructive evaluation techniques, Ultrasonic testing (UT) can play an extremely important role in identifying and ascertaining the size of HICs. Conventional UT techniques show relatively good detection performance but poor accuracy in terms of evaluating HICs due to the major problems caused by ultrasonic beam divergence and the existence of linked cracks. Therefore, developing Cscan imaging techniques and identifying stepwise cracks with UT scanning experiments are necessary for added information accuracy on HICs. In this study, double-faced and single-frequency C-scan imaging with Synthetic aperture focusing technique (SAFT) were applied to describe the images of HICs in specimens with the location and size information close to those of the actual defects and identify clustered parallel cracks. Moreover, the Technique for the identification of flaw signal using deconvolution (TIFD) was applied to determine the presence of stepwise cracks in the ultrasonic testing experiment using a 45-degree shear wave.

The preferential contraction ratios of transversus abdominis on the variations of knee angles during abdominal drawing-in maneuver in wall support standing

황영인,김좌준,박두진 한국운동재활학회 2014 JER Vol.10 No.2

The objective of this study was to determine appropriate knee angles for the abdominal drawing-in maneuver (ADIM) through evaluation of changes in contraction ratios of the abdominal muscles and activity of quadriceps muscle in relation to changes in knee angles occurring while the ADIM is performed in the wall support standing (WSS). 20 subjects performed the ADIM at different knee angles (0°, 20°, 40°, 60°) in random order, standing at a point 6 inches away from the wall with the spine maintained in the neutral position. The WSS with knee flexion at 20° showed significantly higher preferential contraction ratio (PCR) of transversus abdominis (TrA) compared to other positions (0°, 40°, 60°). Therefore, performing the ADIM in the WSS with knee flexion at 20° ap-pears to be the most appropriate position for TrA PCR.