• 한국구조물진단유지관리공학회 논문집
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• 제10권3호
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• pp.185-196
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• 2006

파괴인성은 균열의 개시와 전파에 대한 재료 고유의 상수로서 파괴역학에서 가장 중요한 재료상수 중의 하나이다. 콘크리트의 모드 I 파괴인성 측정에 대하여 RILEM 기술 위원회 89-FMT는 2-파라메타 모델에 근거한 3점 휨 시험법을 제시하였다. 그러나 혼합모드에 대한 시험법은 아직까지 표준으로 제안된 방법이 없는 실정이며, 또한 RILEM에서 제안한 3점 휨 시험법은 실험법이 복잡하다. 따라서 본 연구에서는 굵은골재의 최대치수가 각각 20mm, 40mm이고, 동일한 설계기준강도를 가지는 콘크리트로써 다양한 크기의 브라질리언 디스크를 제작하였다. 그리고 브라질리언 디스크의 모드 I 파괴인성을 RILEM 3점 휨 시험결과와 비교하였다. 비교 결과, 굵은골재의 최대치수에 따른 브라질리언 디스크의 적정 크기(두께, 직경) 및 노치 길이 비를 제시하였다. 또한 모드 I 시험으로부터 결정된 치수의 브라질리언 디스크로 혼합모드 시험을 수행한 결과 디스크 시편은 혼합모드 파괴의 연구 및 시험에 유용함을 알 수 있었다. 모드 I 및 혼합모드 시험에서 브라질리언 디스크의 응력확대계수는 유한요소해석(FEA)으로 구하였으며 FEA의 결과를 검증하기 위하여 5개항 근사법(Five terms approximation)에 의한 결과와 비교하였다.

• Physical Therapy Rehabilitation Science
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• 제11권3호
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• pp.370-375
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• 2022

Objective: The purpose of this study was to compare the hip joint muscle strength of patients with chronic back pain with lumbar instability and normal subjects. Design: A case control study. Methods: Five types of lumbar instability test were conducted on forty young women with chronic low back pain for more than six months, and those who had 3 or more positive tests were selected as subjects. To select chronic back pain patients with lumbar instability group, aberrant movement patterns during lumbar flexion test (FMT), prone instability test (PIT), posterior-anterior mobility test (PAT), passive lumbar extension test (PLE), and pressure bio-feedback (PBF) were applied. In addition, a digital muscle strength meter was used to measure the hip flexor, extensor, adductor, and abductor muscles of chronic low back pain patients with lumbar instability group (n=20) and normal subject group (n=20). Results: As a result of comparing the hip joint muscle strength between the chronic back pain patient group with lumbar instability and the normal group, there were significant differences in the hip extensor, abductor, and adductor muscles (p<0.05). Conclusions: Patients of chronic back pain with lumbar instability were found to have weak hip joint muscle strength. Therefore, this study suggest that include hip joint strength exercise for functional recovery of chronic back pain patients.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2004년도 제9차 학술대회 초록집
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• pp.23-32
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• 2004

The chemotherapy sensitive Lewis lung carcinoma (LLC) and chemotherapy resistant Lewis lung carcinoma (CR-LLC) tumors concurrently implanted in mice, and compare these findings with histological macroscopic observations against 3D reconstruction of Fluorescence Molecular Tomography (FMT) preformed in vivo on the same animals. For the 3D image reconstruction we used 32 laser source images, a flat image and 3D surface rendering that confused for 3D Fluorescence Molecular Imaging (FMI). A minimum of ten tissue sections were analyzed per tumor for quantification of the TUNEL-positive cells, cell-associated Cy5.5-Annexin and vessel-associated Alexa Fluor-Lectin. These are useful apoptosis and angiogenesis markers, and they serve as validation experiments to data obtained in vivousing a Cy5.5-Annexin V conjugate injected intravenously in chemotherapy-treated animals carrying the tumors studied histologically. We detected higher levels of apoptosis and corresponding higher levels of Cy5.5 fluorescence in the LLC vs. the CR-LLC tumors according to tissue depth and these findings confirm that in vivo staining with the Cy5.5-Annexing conjugate correlates well with in vitro TUNEL staining and is consistent with the higher apoptotic index expected from the LLC line. There appeared to be 1.38% more apoptosis for LLC than CR-LLC. Consequently there is good correlation between the histology results and in vivo fluorescence-mediated optical imaging. In conclusion the apoptotic images of 3D FMI were validated by microscopic histological image analysis. This is a significant result for the continuous progress of fluorescence 3D imaging research.

• 수산해양기술연구
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• 제48권3호
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• pp.256-268
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• 2012

The Nemopilema nomurai is a large jellyfish attaining a weight of 200 kg and bell diameter of 2 m when fully grown. To prevent damage to this species, this study determined the acoustic characteristics of N. nomurai using frequencies 38 and 120 kHz. The CPUE of N. nomurai and the averaged SV of 38 and 120 kHz had a lower (+) correlation coefficient and relationship at 120 kHz (R=0.51) than at 38 kHz (R=0.15) was significant. In addition, the averaged SV at 120 kHz was higher than at 38 kHz. The ${\Delta}MVBS_{120-38}$ in section catches ${\geq}97.8%$ wet mass of N. nomurai was -2.2 to 5.6 dB. The ${\Delta}TS_{120-38}$ in situ TS was extracted in sections catches of only N. nomurai by FMT. It was found that the averaged in situ ${\Delta}TS_{120-38}$ were at 0.6 and 0.1 dB. Furthermore, it results showed a close relationship between the bell diameter and TS of N. nomurai. The dominance of smaller N. nomurai (11.0~20.0 cm bell diameter in the air) corresponded to a similar proportion of low TS values (-69.0~-65.0 dB). A small number of larger N. nomurai (25.0~38.0 cm bell diameter in the air) were collected, in which TS values were the highest (-62.0~-58.0 dB).

• 수산해양기술연구
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• 제48권3호
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• pp.242-255
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• 2012

The Nemopilema nomurai a very large jellyfish that has been found in the East China Sea and is now are migrating to Korea and Japan. To investigate the occurrence of N. nomurai based on the changing marine environment of the East China Sea, we conducted field survey in the early summer from 2006-2008. We observed the marine environment using CTD and the occurrence of N. nomurai using FMT and bottom trawling. We caught the most N. nomurai in 2007 and the fewest in 2008 and environment factors influencing its are more sensitive temperature than salinity. Large quantities of N. nomurai with a small bell diameter were caught in 2007 and large individuals with a significant bell diameter were caught in 2008. This appeared which between the catch and bell diameter of N. nomurai had (-) correlation (R=-0.988, p=0.098). Meanwhile, the spatial distribution of N. nomurai concentrations in lower salinity mixed seawater inflow in Changjiang Diluted Water.